REVISTA CONSTRUCŢ Ş form TI... · 2017-11-20 · TEHNOLOGIA INOVATIVĂ – Revista „Construc ţia de maşini” nr. 4 / 2010 leading European company innovation can be very handy

REVISTA CONSTRUCŢIA DE MAŞINI - SERIE NOUĂ

Anul 62, Nr. 4 / 2010

Din sumar

TEHNOLOGIE INOVATIVĂ / INNOVATIVE TECHNOLOGY ECONOMIE INDUSTRIALĂ. ECONOMIA CUNOAŞTERII /

INDUSTRIAL ECONOMY. KNOWLEDGE ECONOMY

EDUCAŢIE,

DEZVOLTARE ŞI INOVARE / EDUCATION, DEVELOPMENT AND INNOVATION

ISSN 0573 – 7419 EDITOR: ICTCM – CITAf 041303 Bucuresti Şos. Olteniţei nr. 103, sector 4, O.P. 8 Tel: 021 332.37.70/234 Fax: 021 332.07.75 / 021 332.31.95 E-mail: [email protected]

Responsabil editor: Irina Rădulescu Responsabil difuzare: Ionuţ Dimache INFORMAŢII, ABONAMENTE: Revista este evaluată CNCSIS la categoria B+, apare trimestrial. Abonamentele se fac direct, prin dispoziţie de plată sau mandat poştal, trimis pe adresa revistei. CONT – ICTCM: nr. RO58 RNCB 0075 0352 1240 0001; BCR sector 4 TIPAR: ICTCM – CITAf COPYRIGHT 2003 Toate drepturile asupra acestei ediţii sunt rezervate ICTCM – CITAf. Nu este permisă reproducerea integrală sau parţială a articolelor din revista „Tehnologia Inovativă” fără consimţământul scris al editorului. Opiniile exprimate în revistă aparţin semnatarilor articolelor, fără să reflecte obligatoriu şi punctul de vedere al editorului.

TEHNOLOGIA INOVATIVĂ – Revista „Construcţia de maşini” nr. 4 / 2010

ANUL 62 / 2010 – NR. 4

TEHNOLOGIA INOVATIVĂ

REVISTA CONSTRUCŢIA DE MAŞINI

COLEGIUL DE REDACŢIE Octavian BOLOGA - Universitatea „Lucian Blaga” din Sibiu

Olivier BONNEAU – Universitatea din Poitiers, Franţa

Ion BOSTAN – Universitatea Tehnică a Moldovei

K.D. BOUZAKIS – Aristoteles University of Thessaloniki, Grecia

Doug BRANHAM - Lubrication Systems Company, Houston, Texas, USA

Dan BRÎNDAŞU - Universitatea „Lucian Blaga” din Sibiu

Mircea CIOBANU - Universitatea „Ştefan cel Mare” din Suceava

Valeriu DULGHERU – Universitatea Tehnică a Moldovei

Dan FILIPOIU - Universitatea POLITEHNICA din Bucureşti

Michel FILLON – Universitatea din Poitiers, Franţa

Mohamed HAJJAM – Universitatea din Poitiers, Franţa

Tudor ICLĂNZAN - Universitatea „Politehnica” din Timişoara

Nicolae Valentin IVAN - Universitatea „TRANSILVANIA” din Braşov

Gheorghe MOGAN – Universitatea „TRANSILVANIA” din Braşov

Ilie MUSCĂ - Universitatea „Ştefan cel Mare” din Suceava

Nicolae OANCEA - Universitatea „Dunărea de Jos” din Galaţi

Dumitru OLARU - Universitatea Tehnică „Gheorghe Asachi” din Iaşi

Juozas PADGURSKAS – Lithuanian University of Agriculture, Lithuania

Radu POPESCU – Academia Română - INCE – CEIS, Bucureşti

Tudor PRISĂCARU - Universitatea POLITEHNICA din Bucureşti

Vasile PUIU - Universitatea din Bacău

Stanisław PYTKO - University of Science and Technology, Kraków, Poland

Alexandru RĂDULESCU - Universitatea POLITEHNICA din Bucureşti

Minodora RÎPĂ - Universitatea „Dunărea de Jos” din Galaţi

Lucian TUDOSE - Universitatea din Cluj

Thami ZEGHLOUL – Universitatea din Poitiers, Franţa


COMITET ONORIFIC

Gheorghe AMZA - Universitatea POLITEHNICA din Bucureşti

Niculae Napoleon ANTONESCU – Universitatea „Petrol şi Gaze” din Ploieşti

Traian AURITE - Universitatea POLITEHNICA din Bucureşti

Gavrilă CALEFARIU - Universitatea „TRANSILVANIA” din Braşov

Mircea COZMÎNCĂ - Universitatea Tehnică „Gheorghe Asachi” din Iaşi

Emanuel DIACONESCU – Universitatea „Ştefan cel Mare” din Suceava

Marian GHEORGHE - Universitatea POLITEHNICA din Bucureşti

Constantin ISPAS - Universitatea POLITEHNICA din Bucureşti

Valeriu JINESCU - Universitatea POLITEHNICA din Bucureşti

Aurel JULA - Universitatea „TRANSILVANIA” din Braşov

Constantin MINCIU - Universitatea POLITEHNICA din Bucureşti

Eugen PAY - Universitatea de Nord din Baia Mare

Iulian POPESCU - Universitatea din Craiova

Aurelian VLASE - Universitatea POLITEHNICA din Bucureşti

Ioan VOICA - Universitatea POLITEHNICA din Bucureşti

EDITOR

Oficiul de Informare Documentară pentru Industrie, Cercetare, Management din cadrul

Centrului Incubator Tehnologic de Afaceri S.C. ICTCM S.A. BUCUREŞTI

RESPONSABIL EDITOR

Irina Rădulescu

REDACTOR Irina Rădulescu

WEBMASTER Ramona Ioanid


ABSTRACTS “INNOVATIVE TECHNOLOGY” 4 / 2010

SYNTHESIS THE INFORMATIONAL SUPPORTED SYSTEM AT TECHNICAL

OPERATION "ON CONDITION" OF CONTROLLED OBJECTS

A. Aslanyan , A. Belskaya

National Aviation University, UKRAINE

Structure of the integral informational computing system for processing of parameters, which are characterized the technical condition of control object, is offered, that allows to close control loop of technical condition controlled object by negative feedback, what enable to pass from technical operation of object "on resource " to its technical operation "on condition ".

LA SEPARATION TRIBO-ELECTROSTATIQUE

DES DECHETS ELECTRIQUES (TRIBO-ELECTROSTATIC SEPARATION

OF ELECTRICAL WASTE )

Mirela G. Radu1, Lucian Dascalescu2, Sorin Cănănău1, Alexandru Rădulescu1

1 Dep. Eléments de Machines et Tribologie,

Université “Politehnica“ de Bucarest, ROMANIA 2IEEE fellow, Institut Universitaire de

Technologie,FRANCE

Electrostatic applications are often used today in many areas. Tribo-electrostatic separation is used for sorting of granular mixtures through the application of electrical forces acting on charge or polarization. Thus, these techniques are mainly used for separating dry particles. In this research was also utlise the Taguchi method. Using an experimental stand, a series of experiments on a mixture of polyamide and polycarbonate PC and PA has been realized.

ETUDE EXPERIMENTALE SUR LE COMPORTEMENT RHEOLOGIQUE

DES HUILES PROCESS F913 ET CASTROL MAGNATEC DIESEL

(EXPERIMENTAL STUDY ON THE RHEOLOGICAL BEHAVIOR

OF PROCESS F913 AND CASTROL MAGNATEC DIESEL OILS)

Guillaume Grandviennot*, Alexandru Rădulescu**

* Ecole Nationale D’Ingenieurs de Tarbes, FRANCE ** Université “POLITEHNICA” Bucarest,

ROUMANIE

The paper proposes to analyze the rheological behavior of lubricants used in automotive engine lubrication. The properties considered are the rheological model of the lubricant in fresh and used state (with a degree of wear) and the variation of viscosity with temperature for various velocity gradients imposed. For these properties, it was determined by the method of regression analysis the laws of variation of the parameters, and also the confidence intervals.

ESSAIS EXPERIMENTALES SUR LE COMPORTEMENT MECANIQUE

DE POLYTETRAFLUORETHYLENE (PTFE) (EXPERIMENTAL TESTS

ON THE MECHANICAL BEHAVIOR OF POLYTETRAFLUOROETHYLENE (PTFE))

Eugenia Costache1, Mohamed Hajjam2, Aurelian Fatu2, Alexandru Rădulescu1, Sorin Cănănău1,

1 Dep. Eléments de Machines et Tribologie,

Université “Politehnica“ de Bucarest, ROMANIA 2Genie Mécanique et Systèmes Complexes,

Université de Poitiers, ENSMA, France

The paper proposes the study of mechanical behavior of plastics, especially for polytetrafluoroethylene (PTFE). We presented the general properties of plastics, with emphasis on mechanical behavior of polymeric materials. The experimental tests were conducted on a tensile machine INSTRON 4302, for cases of imposed displacement and applied load. The curves obtained were used for numerical modeling. Finally, we made comparisons between results and conclusions were presented from the behavior of PTFE.


ELECTROCOMPOSITE WITH ZINC ALLOYS MATRIX AND AL2O3 NANOPARTICLES

R.Stancu1, Gh. Badea2, G. Diacov2, M. Hriscu2,

D. Ciupitu3, E. Alexandrescu3 1Scoala cu clasele I-VIII 162, Bucharest, Romania,

[email protected] 2S.C.ICTCM S.A , Bucharest, Romania,



[email protected] 3S.C.METAV Cercetare Dezvoltare, Bucharest,

Romania, [email protected] This paper presents experimental date regarding nanocomposite coatings with Zn-Fe(1-3%) and Zn-Ni(7-15%) metallic matrix and ceramic nanoparticles of aluminium oxide. Deposits were obtained using alkaline electrolytes. The effect of different concentration of particles on corrosion resistance was studied. Structural characterization using scanning microscopy showed that the deposits are nanocrystalline.

MODELE DE ANALIZA

A NANOCOMPOZITELOR ELECTRODEPUSE (MODEL ANALYSIS

OF NANOCOMPOSITES ELECTRO-LAID-DOWN)

Leonard Teodoru1 , Valentin Mihailescu2 , Alexandru Ionescu3, Gratiela Epureanu4,

1,2,3,4 Foundation Professor Constantin Popovici

"Bucharest, Romania [email protected], [email protected],

alex.fpcp @ gmail.com, [email protected]

It presents the preliminary analysis of electro deposited nanocomposites parameters model equations for determining mathematical models for the electronic filing process. It describes a simplified model and boundary conditions for models under consideration, the simplifying assumptions and conditions upon which the deposit.

THE STUDY OF ROUGHNESS

AND RESISTANCE TO CORROSION OF DENTAL ALLOYS

IN THE ORAL ENVIRONMENT

A.D. Cherciu Ciobotaru, Adina Oana Armencia, Maria Ursache

Faculty of Dental Medicine, „Gr.T.Popa”University of

Medicine and Pharmacy, Iaşi, ROMANIA

email: [email protected], email:[email protected]

Through its enzymatic process, the oral environment is setting out catabolism chemical products, having unfavourable effects on the used in restoration. Increase Cu and Sn percent increase a corrosion velocity and surface aspect. This decrease with increase Mo and Co percent through passive effect. Increase Fe concentration increase corrosion velocity. Al is very affected in Cu presented. Increase percent Si increase corrosion velocity to galvanic effect. Corrosion implies the presence of an electrolyte around the metal or alloys subjected to corrosion, damaging of the crystaline network of the material being governed by the electrochemical laws of kinetics.

COLABORĂRI ŞI REŢELE PENTRU DEZVOLTARE

(COOPERATION AND DEVELOPMENT NETWORKS)

Radu Popescu

Academia Română –INCE-CEIS, Bucureşti,

ROMÂNIA, e-mail: [email protected]

In the Global Knowledge Economy the traditional difference between production and the use of knowledge it is not any more important and relevant. The challange consists in the assurance that inovative process is a cooperative one, involving producers (the public sector till a higher level) and consumers (the private sector largly expanded). Such kind of cooperation requests the buildind ofclose relationship between the research comunity and business comunity, as social as professional point of view.

STRATEGIA MICILOR ÎNTREPRINDERI

ROMÂNEŞTI ŞI INOVAŢIA, CA FACTOR DE SUCCES PE PIAŢA

EUROPEANĂ (ROMANIAN SMALL BUSINESS ENTREPRISES

STRATEGY AND INNOVATION, AS SUCCESS FACTOR ON

EUROPEAN MARKET)

Adina Gabriela Dascălu

University of Craiova, Craiova, ROMANIA, e-mail: [email protected]

Innovation is a process whose objective is the achievement of a valuable, original and creative outcome. It gives the invention its economic dimension. Innovation-oriented firms are more likely to win over competitors, either by price reduction by following the reduction of costs, or by making better products that bring greater value to customers. For a


leading European company innovation can be very handy having regard to available funds, unlike small businesses, which can be very innovative, but often encounter financing difficulties. However, there are several less expensive types of strategies the former can use, which merged with a correct prioritization can create a strong position on the European market, even for a small firm.

CERCETAREA IN ROMANIA – TRENDURI ACTUALE

(RESEARCH IN ROMANIA - PRESENT TRENDS)

Nicoleta Gudanescu

Universitatea Nicolae Titulescu, Bucuresti,

ROMANIA, e-mail: [email protected] The paper work presents the status of Romanian National Innovation System and National and Regional Innovation Strategies. The innovation based entrepreneurship and innovation indicators in Romanian SMEs are high-lighted, also. The paper work provides in the mean time information about National Research and Development System, Innovation and Business Infrastructure, specific indicators of Regional Innovation Strategies, and possible orientation for future policy actions.

ICT STRATEGY SUPPORT FOR BUSINESS DEVELOPMENT AND INNOVATION

Nicoleta Gudănescu*, Adrian Nicolau**,

Nicolae Titulescu University, Bucharest, ROMANIA,

** SC AVANGARDE TECHNOLOGIES CONSULTING, Bucharest, ROMANIA,

E-mail:[email protected], [email protected]

This paper work emphasizes the importance of the strategic management for the present companies, no matter the dimension or the field. More important becomes thou, the implementation and utilization of systems that represents support for business processes and information flows because of focus on co-operation and networking activities of today’s companies. The models created for running businesses are creative but in some cases these are not paying attention to the ICT point of view. There is evidently a large gap between business and technology development and knowledge about those activities. The paper presents the challenges of business and ICT development thorough the strategies, as global strategies of the companies or as units strategies but always have to be handled as integrated and related activities.

THE CORRELATION BETWEEN THE STUDIES IN THE FIELD OF INFORMATION

TECHNOLOGY AT THE LEVEL OF THE ERP PROGRAMS AND THE PROGRESS

OF THE INDUSTRIAL TEHNOLOGICAL MANAGEMENT

Andronie Maria, Băluţă Aurelian Virgil

Spiru Haret University, Bucharest, ROMANIA,

e-mail: [email protected] One of the improvement trends of the industrial process management consists in using on an increasingly large scale the tools provided by computer science. Basically there is a continuous improvement of the information tehnologies and they permanently adapt to specific processes. Certain evolutions have the tendency to become precious conceptual generalizations or to engender an infrastructure specific to a new era, that of knowledge. In this article we stress the utility of the information technology studies in general and concerning the ERP programs in particular for the technological management processes of the industrial processes.


CUPRINS

TEHNOLOGIE INOVATIVĂ / INNOVATIVE TECHNOLOGY

1. SYNTHESIS THE INFORMATIONAL SUPPORTED SYSTEM AT TECHNICAL OPERATION "ON CONDITION" OF CONTROLLED OBJECTS pag. 9 Aslanyan, A. Belskaya National aviation university, UKRAINE

2. LA SEPARATION TRIBO-ELECTROSTATIQUE DES DECHETS ELECTRIQUES pag. 15

Mirela G. Radu1, Lucian Dascalescu2, Sorin Cănănău1, Alexandru Rădulescu1 Dep. Eléments de Machines et Tribologie, Université “Politehnica“ de Bucarest, ROMANIA 2IEEE fellow, Institut Universitaire de Technologie,FRANCE

3. ETUDE EXPERIMENTALE SUR LE COMPORTEMENT RHEOLOGIQUE

DES HUILES PROCESS F913 ET CASTROL MAGNATEC DIESEL pag. 21 Guillaume Grandviennot *, Alexandru Rădulescu ** Ecole Nationale D’Ingenieurs de Tarbes, FRANCE ** Université “POLITEHNICA” Bucarest, ROUMANIE

4. ESSAIS EXPERIMENTALES SUR LE COMPORTEMENT MECANIQUE DE POLYTETRAFLUORETHYLENE (PTFE) pag. 27 Eugenia Costache1, Mohamed Hajjam2, Aurelian Fatu2, Alexandru Rădulescu1, Sorin Cănănău1, 1 Dep. Eléments de Machines et Tribologie, Université “Politehnica“ de Bucarest, ROMANIA 2Genie Mécanique et Systèmes Complexes, Université de Poitiers, ENSMA, FRANCE

5. ELECTROCOMPOSITE WITH ZINC ALLOYS MATRIX AND Al2O3 NANOPARTICLES pag. 33

R. Stancu1, Gh. Badea2, G. Diacov2, M. Hriscu2, D. Ciupitu3, E. Alexandrescu3

1Scoala cu clasele I-VIII 162, 2S.C.ICTCM S.A , 3S.C.METAV Cercetare Dezvoltare, Bucharest, ROMANIA

6. MODELE DE ANALIZA A NANOCOMPOZITELOR ELECTRODEPUSE pag. 37

Leonard Teodoru, Valentin Mihailescu, Alexandru Ionescu, Gratiela Epureanu, Foundation Professor Constantin Popovici,Bucharest, ROMANIA

7. THE STUDY OF ROUGHNESS AND RESISTANCE TO CORROSION OF DENTAL ALLOYS IN THE ORAL ENVIRONMENT pag. 43

A.D. Cherciu Ciobotaru, Adina Oana Armencia, Maria Ursache Faculty of Dental Medicine, „Gr.T.Popa”University of Medicine and Pharmacy, Iaşi, ROMANIA ECONOMIE INDUSTRIALĂ. ECONOMIA CUNOAŞTERII / INDUSTRIAL ECONOMY. KNOWLEDGE ECONOMY

8. COLABORĂRI ŞI REŢELE PENTRU DEZVOLTARE pag. 49 Radu Popescu Academia Română –INCE-CEIS, Bucureşti, ROMÂNIA EDUCAŢIE, DEZVOLTARE ŞI INOVARE / EDUCATION, DEVELOPMENT AND INNOVATION

9. STRATEGIA MICILOR ÎNTREPRINDERI ROMÂNEŞTI ŞI INOVAŢIA, CA FACTOR DE SUCCES PE PIAŢA EUROPEANĂ pag. 53

Adina Gabriela Dascălu Universitatea din Craiova, România


10. CERCETAREA IN ROMANIA – TRENDURI ACTUALE pag. 57 Nicoleta Gudanescu Universitatea Nicolae Titulescu, Bucureşti, ROMÂNIA

11. ICT STRATEGY SUPPORT FOR BUSINESS DEVELOPMENT AND INNOVATION pag. 65 Nicoleta Gudănescu1, Adrian Nicolau2 1 Nicolae Titulescu University, 2 Sc Avangarde Technologies Consulting, Bucureşti, ROMÂNIA

12. THE CORRELATION BETWEEN THE STUDIES IN THE FIELD OF INFORMATION TECHNOLOGY AT THE LEVEL OF THE ERP PROGRAMS AND THE PROGRESS pag. 71

OF THE INDUSTRIAL TEHNOLOGICAL MANAGEMENT Andronie Maria, Băluţă Aurelian Virgil Spiru Haret University, Bucureşti, ROMÂNIA


9

SYNTHESIS THE INFORMATIONAL SUPPORTED SYSTEM AT TECHNICAL OPERATION "ON CONDITION"

OF CONTROLLED OBJECTS

A. Aslanyan , A. Belskaya

National Aviation University, UKRAINE

ABSTRACT Structure of the integral informational computing system for processing of parameters, which are characterized the technical condition of control object, is offered, that allows to close control loop of technical condition controlled object by negative feedback, what enable to pass from technical operation of object "on resource " to its technical operation "on condition ".

KEYWORDS: Computer science, Information technology, Control object.

1. INTRODUCTION

Method of technical operation "on resource" with strategy of technical maintenance "on time" is the traditional and during operation of control objects different technical purposes, including aviation turbo engines, power-plants of compressor stations main gas-pipelines, gas-turbine plants for ships, is used until now. As known, such method the operation aviation equipment results in 0,3-0,9 its nonoperated actuals resources.

From other side, economic situation, that presently exist, forces to extend term of operate for whole row of objects (for example, majority of gas-pumping aggregates (GPA)), parts of Ukrainian gas transport system, were entered into operation more than 30 years ago and, presently, primary task is an extension of operation term these aggregates). It should be noted, that, already, after GPA working off over 15-20 years technical and economical indexes are getting worse substantially (the. volumes of harmful extras in an atmosphere are increasing, reliability of its nodes diminishes considerably, expenses for maintenance and repairs are growing).

Basic normative act, which is used for regulating maintenance organization of GPA with a turbine drive, is «Temporal position of preventive repairs system for gas-turbine plants with centrifugal superchargers», in accordance with which, the terms repairs realization are accidental.

Without taking into account of actual condition

of aggregate, its structural features, time from start of operation, identical terms for repairs realization of all types gas-turbines, have been recommended. If substantially outspent resource, such strategy of maintenance necessarily includes unscheduled work for restoration, because of refusals in separate GPA nodes, volumes and terms of which, are casual and have sufficiently large dispersion.

Characteristic feature the strategy of operation "on time" is in unclosed control loop of technical condition (statistical feedback, that characterized by large delay and dispersion, cannot be examined as a feedback). For object under operation, the closing of technical condition control loop by negative feedback on period between major repairs, possibly exceptionally in result of continuous and deep control parameters, which characterize its technical condition. Such control allows to identify disrepairs on the stage of their origin and to predict their further development.

At the declining parameters that characterize a technical condition of control object from a norm, the feedback immediately will provide correcting of this condition. Because presently, during operation many control objects, the use strategy of maintenance "on condition" is not assumed, and, consequently, built-in systems for control the defined parameters are absent in them, and parameters themselves are not assigned by the developer, the task of organization maintenance "on time" with prognostications about ofpre-refusal condition, and also technical


10

maintenance "on condition" must to be decided on the base of regular control-measuring systems (CMS). Taking into account this circumstance, is offered integral information computing system (IICS) of control the teclmical condition of object, is represented on Fig.l. 2. CHARACTERISTICS OF AN INTEGRAL

INFORMATION COMPUTING SYSTEM

The CMS of control object is the primary information generator about current values of functional parameters. At diagnostic value measurable parameters, as a rule, are divided on groups.

For example, among parameters that measurable the CMS SAT-05 for GPA type GPP 10-01, the most diagnostic value is possessed by next parameters: temperature after a turbine, pressures before and after a compressor (at such combination the control of the temperature before turbine is provided more reliable, if to compare with its direct

measuring), frequencies of rotation (high accuracy and stability of measuring), temperature of butter in a greasing system, billow vibration, temperature of on exit of combustion chamber, a pressure on turbine exit, temperature in cavity of wheels turbines, temperature on exit of compressor, expense of fuel.

Because in this example parameters, which characterize the technical condition of object, are not assigned by the developer, a primary task is a task of forming the vector of determining parameters. In articles [I], [2] is offered the method choosing of determining parameters that characterize the technical condition of turbo engine, which is based on the circumstance that functioning of control object in regular modes is characterized by small deviations of functional parameters from their basic values.

Therefore, as parameters that characterize technical condition of object under operation is offered to exam parameters of its linear dynamic model, in the complement of which are entered functional parameters with most diagnostic value.

Fig.l. Structurally functional scheme of IICS processing the parameters characterizing technical condition of object

Fig.2. Structure scheme of continuous monitoring system for parameters that characterize technical conduction of object in transient behavior


11

In this case, continuous monitoring system of parameters that characterize the technical condition of object is intended for realization the continuous control of parameters linear dynamic model, the determination of moments their correction and the calculation of new values parameters of linear dynamic models, which are correspond to changing technical condition of object.

Thus, the model of object and object "get older" together.

Structure scheme of continuous monitoring system for parameters that characterize a technical condition of object, is represented on Figure 2.

In structure scheme on Figure 2:

( )pW - transfer functions matrix of linear dynamic model for control object,

( ) ( ) ( )( ) ( )pWpWpWpW TT 1−+ = - pseudo inverse matrix for ( )pW .

Structure scheme for determination parameters of transfer functions, that format i-th line of object matrix under control, is represented on fig.3. With use of the method main components, between parameters of the dynamic model of control object exude statistically independent (or poorly dependent). Procedure of forming the vector of determining parameters is carried out in the proper block.

In addition, this unit carried out the appointment of pre-emptive tolerances to determined parameters. A database is a single generaly informative resource of system, which is intended for arrangement storage of all information types at all stages of processing. A database can be divided into two basic blocks: block of preliminary information, where primitive accumulation is conducted on for every measurable parameter and block of statistical information, where results of statistical processing at different stages are kept.

The block of parameters statistical processing is intended for statistical processing thread of information about current values of parameters that characterize a technical condition of object and information from a database. The block of current condition estimation decides the verification task of distributing laws of measuring results for coordinates of determining parameters vector.

Estimation of current condition is conducted by the method of hypotheses verification about expected value and dispersion. Through parametric and nonparametric methods, the estimation of probability about hitting the numerical statistical descriptions for coordinates of determining parameters vector is conducted.

The block of prognostication is intended for estimation of probability that forecast value of determining parameters vector will be in the field of admittance.

Fig.3. Structure scheme that allows parameters determination of transfer functions,

formatting the line of matrix object under control

3. DYNAMIC MODEL OF THE SYSTEM

The description of object technical condition by parameters of its linear dynamic model is grounded for the wide class of objects, if their system of control is functioning on the mode of stabilizing, i.e. on the mode of the small rejections functional parameters from their basic values.

In general, the linearized system of equations

in deviations to the original nonlinear model of control object, is unstationary, and has the form:

( ) ( ) ( ) ( ) ( )tutBtxtA

dttxd ~~~

+= (l)


12

where: ( )tx~ , ( )tu~ - vectors of dimension n and m, respectively, m ≤ n, ( )tA , ( )tB A(r), B(/) -time-varying matrix, size n × n and n × m, respectively.

Then examines one possible solution of the faults localization in the original nonlinear controlled dynamical system in the case, when system, that obtained by linearization, is not stationary, i.e. has the form (1). The task is solved both in static and dynamic modes based on the quorum-method.

Denote ( )tx~ - the reaction of the linearized system at the input disturbance ( )tu~ , 0tt ≥ .

Then, for 0tt >

( ) ( ) ( ) ( ) ( ) ( ) ( )∫ −ΦΦ+Φ=t

t

duBttxttx

0

~~~ 10 ττττ ,

where ( )tΦ - fundamental matrix solution of the

homogeneous system ( ) ( ) ( )txtAdt

tdx= , that satisfy

( ) Et =Φ 0 , E - identity matrix of size n × n. As ( ) 0~ =tu at 0tt ≤ , then ( ) 0~

0 =tx . Given this, denote

( ) ( ) ( ) ( )∫ −ΦΦ=t

t

dBtttH

0

10, τττ (2)

It is obvious that for each 0tt ≥ , ( )0, ttH - it is the matrix, size n × m , and ( ) 0, 00 =ttH .

Let the static mode of the original nonlinear dynamical system correspond output signal ( )txst and input signal ( )tust . At time 0t act on ( )tust using small perturbation ( )tu~ .

Denote ( )tx - reaction of diagnosed object on the perturbed control ( ) ( )tutust

~+ at 0tt > . Then the difference ( ) ( ) ( )txtxtx st−=∆ , will coincide with ( )tx~ at 0tt > , and will be zero at 0tt = , up to terms

of higher order. Under the refusal of i-channel in system means inequality ( ) ( )txtx ii

~≠∆ at a certain time interval 0tt > . Inequality, as well as equality is understood to within infinitesimals of higher order.

At heuristic assumption about the impossibility of the simultaneous failure of two or more channels of the system, necessary to establish a failure in the system, if any, and also specify a channel containing the failure.

At time 0tt = will indignant j-coordinate of the vector control ( )tust onto a small jump jλ ,

mj ,1= , without disrupting the normal functioning of the object diagnostics, i.e. let

( ) ( )( )Tjj ttu 0,,1,,0~ KKλ= .

Considering (2), will obtained the response of the linearized system (1) to a perturbation ( )tu j~ in the form of:

( ) ( ) ( ) ( )( )Tnjjjj

j tthtthtthtx 00201 ,,,,,,~ Kλ= ,

mj ,1= , 0tt > , and, consequently, with accuracy up to infinitesimals of higher order

( ) ( ) ( ) ( )( )Tnjjjjj tthtthtthtx 00201 ,,,,,, Kλ=∆ (3),

at 0tt >

Equation (3), is a condition of collinear between vector ( )tx j∆ and vector, which coincides with the j -th column of matrix ( )0, ttH , so we can write the following system of equations:

( ) ( )

( )( ) ( )

( )( ) ( )

( )0

0

02

202

01

101

,,

,,

,,

tthtxtth

tthtxtth

tthtxtth

nj

jnnj

j

jj

j

jj ∆−

==∆−

=∆−

K

at 0tt > . Denote

( ) ( ) ( )( )0

00 ,

,,

tthtxtth

ttij

jiijj

i∆−

=∆ , ni ,1= . (4)

Following the idea of the quorum-method [3],

j∆ represents the average value ji∆ . For averaging

the values j∆ can be used schemes of quorum-element, which are presented in Figure 4.

Input values of each adders 1, 2, .... n are values j

i∆ , ni ,1= , that obtained by (4), and the

result of averaging j∆ , that obtained at the output of the adder S. Output values of each adders 1, 2, .... n

are values of the difference jji

ji ∆−∆=ε .

This difference is amplified by amplifier (Gain). The considered scheme provides on output averaged value

j∆ . As follows from the scheme (fig.4) at equal values of gain K

∑=

=∆n

i

ji

j K1ε .

Since, jji

ji ∆−∆=ε , then

jn

i

ji

n

i

jji

j KnKK ∆−∆=

∆−∆=∆ ∑∑

== 11,


13

or ∑=

∆=∆+∆n

i

ji

jj KKn1

.

From hear

∑=

∆+

=∆n

i

ji

jKn

K

11

With large gain ( )1>>K

∑=

∆=∆n

i

ji

jn 1

1 .

Each ji∆ compared with j∆ in special

scheme of comparison. If object in operative

condition all values jji

ji ∆−∆=ε are within the

limits of admittances. Failure at some coordinates of object state

vector ( )tx causes the excess of allowable values of

the difference jji ∆−∆ and the result of comparison is

used to indicate the presence of failure on the coordinate (channel).

The block-scheme that implements the algorithm for finding faulty channel, is shown on Figure 5.

Fig.4. Scheme of quorum-element

Fig. 5. Block-scheme of diagnosis, using quorum-element


14

In accordance with the scheme, perturbing test signal ( )tu j~ at a time 0tt = is fed to the adder,

after which the total action of control ( ) ( )tutu jst

~+ is applied to the object.

The appointment of extrapolator it is extrapolation of values ( )txst , ( )tust to the interval ( )jTtt +00 , , jT - duration of the test perturbation

( )tu j~ , using values ( )txst , ( )tust , at 0tt < , that obtained from the database.

At values ( )txst and ( )tust calculator determines the elements of the matrix ( )tH on the

interval ( )jTtt +00, , values of vector ( )tx j∆ coordinates on the same interval and coordinates of vector ( )j

njjj ∆∆∆=∆ ,,, 21 K , that must be compare.

4. CONCLUSIONS

1. The structure of the integral information-computer system processing the parameters that characterize the technical condition of maintenance object, is offered, which allows carrying out monitoring and prognostication of these parameters, and is basis of informative support for decision-making at technical maintenance of object. 2. The description of object technical condition by parameters of its linear stationary dynamic model is grounded for the wide class of objects, if their systems of control are function on the mode of stabilizing. 3. The quorum-method can solve the problem of fault isolation in dynamic systems in a more general case, compared with the method based on the pseudoinverse operators. 4. In cases, where linearized system of equations in deviations is stationary, to determine channel containing the refusal, can be used as a method based on pseudoinverse operators, and the quorum-method. The use of the quorum-method allows localizing not only line in the matrix of transfer functions ( )pW , which must be subjected to correction, but the element (elements) in this line. 5. After detection of the element in the matrix of transfer functions ( )pW , that does not correspond to the current technical condition of diagnosis object, new values the parameters of this transfer function can be determine by one of the known methods of identification.

6. The .distinctive feature of approach that offered is: for technical maintenance of object it is possible to use both of maintenance strategy (combined strategy of maintenance "on time" with prognostication of the pre-refusal condition and strategy of maintenance "on condition"), without bringing of the difficult built-in and external checking systems, in conditions of regular functioning and statistical null data about a large number of same objects types, that takes place, for example, for GPA with a turbine drive.

REFERENCES 1. Aсланян A. E., Бєльська O. A., Локалізація

несправностей в лінійних динамічних системах, ОВТ / Збірник наукових праць ЦНДІ ОВТ. – К.: ЦНДІ ОВТ, 2007. – Вип. 18. – С. 3-8.

2. Aсланян A. Э., Бєльська A. A., Забезпечення практичної безвідмовності функціонування газотурбінного двигчна при його експлуатації за технічним станом / Збірник наукових праць ЦНДІ авіації. – К.: ЦНДІ авіації, 2008. – Вип. 19. – С. 3-11.

3. Казак В. М., Бєльська O. A., Метод кворумування при діагностуванні лінійних динамічних систем / Вісник ЦНЦ транспортної академії України., 2007. – No. 10. – С. 84-86.


15

LA SEPARATION TRIBO-ELECTROSTATIQUE DES DECHETS ELECTRIQUES

Mirela G. Radu1, Lucian Dascalescu2, Sorin Cănănău1, Alexandru Rădulescu1

1 Dep. Eléments de Machines et Tribologie, Université “Politehnica“ de Bucarest, ROMANIA 2IEEE fellow, Institut Universitaire de Technologie,FRANCE

ABSTRACT Les applications d’Electrostatique sont souvent utilisés aujourd’hui dans de larges domaines. La. séparation tribo-électrostatique est utilisé pour le tri des mélanges granulaires par l’application des forces électriques qui agissent en charge ou de polarisation. Ainsi, ces techniques sont principalement utilisées pour séparer les particules sèches. Dans la recherche a ete aussi utlise la méthode Taguchi. En utilisant une installation experimentale, une série d’expériences sur un mélange de polyamide et polycarbonate PC et PA a ete realise. MOTS-CLÉS: plan d’expérience, débris, séparation électrostatiques

1. INTRODUCTION

Le plans d’expériences c’est un partie de la formation scientifique de tous les chercheurs ; ils servent à optimiser la manière dont ils organisent leur forme organisationnelle de l’expriment [1]. Le but c’est d’obtenir les meilleurs résultats avec un nombre minimum d’expériences. Aussi la méthode de « plan d’expérience » permet d’obtenir la meilleure précision possible pour les résultats de la modélisation. Avant de commencer à parler de plans, nous devons définir trois termes que nous allons rencontrer très souvent dans cet article. Les variables que nous voulons étudier sont généralement connus comme des facteurs de variation. Les trois limites sont la partie inférieure, la partie supérieure et la limite „zéro”.Le domaine de variation des plans est „une bande de largeur” de minimum (-1) et maximum (1). Un facteur peut prendre plusieurs valeurs dans le domaine de variation [1], [2] (Figure 1).

Fig. 1. Domaine de variation de plan

S’il y a deux facteurs, le deuxième facteur est représenté, à son tour, à un axe. Réunion de la plage de variation de chaque facteur définit la portée d’étude. (Figure 2).

Domained’étude

Facteur 1 -1 +1

+1

-1

Facteur 2

Fig. 2. Variation 2D des facteurs du Plan

En l’absence d’informations sur la fonction de facteurs qui relie les réponses, le plan offre, au contraire, une loi pour l’evolution du processus. Soit on utilise un modèle mathématique ou un modèle postulé, la relation générale est la suivante:

)x,...,x,x,x(fy *i

*3

*2

*1=

où y représente la valeur recherche et xi

* est la valeur des différents facteurs. représentation géométrique d’un régime d’un à deux facteurs nécessitent une représentation en trois dimensions, une dimension de la réponse, pour un model 3D [3] (Figure 3).

Domaine de variation

-1 0 1

L’axe du facteur


16

Fig. 3. Variation 3D des facteurs du Plan

2. PLAN POUR L’ETUDE DES MATERIAUX GRANULAIRES

Le tri sélectif des différents types de matériaux plastique est essentiel pour le recyclage des déchets d’équipements électriques et électroniques (DEEE, déchets d’équipements électriques et électroniques). La technologie de séparation en „corona champ” est ainsi fixée pour l’élimination des débris de fil pour obtenir le débris tribo-electrostatique. La séparation est utilisée lorsque les déchets DEEE représentent un composé de deux types de matières plastiques ou des impuretés qui sont, par nature, non-conducteur.

Tribo-chargement DEEE des déchets avant d’être exposés à des forces de champ électrique dans un séparateur électrostatique, a été validé par la Direction générale en charge de l’industrie du recyclage. Ces dernières années, plusieurs tentatives ont été faites pour améliorer l’efficacité des technologies existantes, qui utilisent des dispositifs de vibration tribo-electriques ou un cyclone.

L’installation expérimentale est présentée dans Figure 4.

Fig. 4. Installation expérimentale

L’installation expérimentale utilise le principe de tribo-electrification, impliquant des particules étant réalisé non pas par la chute libre comme séparateurs sur la marché, mais par voie aérienne.

Le matériau granulaire est introduit dans la chambre et déposé sur un type de distributeur Tribo-chargement. Le jet d’air est produit par un turbocompresseur à commande électronique pour le lit fluidisé qui peut varier la vitesse d’air. Pendant la hausse d’air les granules sont dispersés de manière à prendre place des collisions multiples entre les particules et aussi entre les particules et les murs.

Les particules fluidisées sont conservées pendant 30 secondes, après que l’alimentation en air est arrêtée et les deux électrodes sont alimentées à partir de deux sources d’énergie de polarités différentes.

Les grains chargés positivement et négativement sont attirés par les deux électrodes et lié la par la force électrique. Après l’arrêt des sources de tension, les particules sont aspirées à partir des électrodes et placées dans la cage de Faraday, qui est relié à un électromètre. La masse finale obtenue est mesurée.

3. CONTROL DU PROCESSUS

SPC (Statistical Process Control) est une

méthode de gestion de la qualité par lequel un processus peut être surveillé et si l’intervention peut être nécessaire un ajustement pour corriger ce processus, avant que les résultats peuvent être non-conform.

Après fabrication, les caractéristiques de la qualité sont mesurées ; les résultats sont affichés dans une carte de contrôle de la qualité. L’interprétation correcte des cartes sur le contrôle de qualité tel qu’il est destiné à identifier les erreurs systématiques au début et de créer la possibilité d’intervenir dans le processus de manière appropriée.

Dans un processus technologique complexe, les procédures statistiques nous aident à identifier les écarts précoces systématiques des caractéristiques de qualité des processus qui reste encore dans la tolérance prédéfini. En raison de ce contrôle statistique des procédés et des produits sont parmi les méthodes de prévention de gestion de la qualité.

3.1 CALCUL DE LA CAPABILITE

Pour obtenir une évaluation quantitative de la performance des capacités d’un processus, il faut calculer les indices de performance qui sont la capacité la plus importante de la capacité de machines et de procédés. Capacité de calcul est effectuée dans des conditions réelles de production. Connaissant les capacités de performance d’un processus et nous aide

Mur

PMMA

Electrodes

Chambre d’admission

d’air

Chambre utilisée pour

l’air if

Distribution

air


17

à comprendre ce processus à long terme est contrôlée et, si nécessaire, pour assurer la qualité.

La capabilité du processus, introduit Cp, Cpk et la capacité d'une position de l’installation Cm CMK et aussi la largeur dépendent de la distribution en dehors des limites de la tolérance (LST-limite supérieure de tolérance, LIT-limite inférieure de tolérance) qui peut être la valeur nominale symétrique ou asymétrique, sans valeur nominale.

Les indices sont présentés dans le Tableau 1.

Tab.1 Cm , Cmk capacités de performance de la machine Cp , Cpk capacités de performance du processus capacités de performance de la machine capacités de performance du processus

Ou: S = L’écart-type

=valeur moyenne

Cm , Cp > 1.33 Le procédé est performant en termes de qualité 1.00 ≤ Cm, Cp ≤1.33 Le processus peut devenir efficace dans certaines circonstances Cm , Cp< 1.00 Le processus n’est pas efficace

Pour évaluer la performance d'un processus il faut à tenir compte de divers facteurs qui influencent le processus.

Pour voir ce que nous disons nous avons pris deux séries de 10 essais avec un mélange de matériaux de 50% et 50% ABS, ABS PC.

Le matériel a été introduit dans le dispositif chaque fois que le lit fluidisé et maintenus dans un état de flux pendant 30 secondes. la fréquence de circulation d'air a été de 37,5 Hz et la tension appliquée aux deux électrodes de 16 kV.

Après avoir rejoint les deux électrodes le produit récupéré a été introduit dans la cage de Faraday où nous avons mesuré la tâche [4].

Les résultas des experiments sont presente dans le Tableau 2.

Pour étudier la robustesse de la méthode Taguchi a été utilisé une installation a une plus petite échelle, qui utilise le même principe d’electro-separation Tribo-electrique[3],[4].

Les principes de fonctionnement de l’installation sont similaire à ceux décrite ci-dessus avec la différence que cette installation utilise l’air comprime une fois que les particules sont chargées directement entrer dans la cage de Faraday.

Pour cette série d’expériences nous avons utilisé un plan de Taguchi sur un mélange de polyamide et polycarbonate PC et PA.

Taguchi plan implique l’utilisation de deux facteurs contrôlés et non contrôlés. Les facteurs contrôlés sont appelés facteurs de conception („design”) et les facteurs non contrôlés sont des facteurs „de bruit”, comme nous avons montre dans Chapitre 1 (Introduction).


18

Tab.2

-

358, -

351,

-439

-572

-469

-492

-501

-516

-475

-435

460.

Q2 - 243 - 257 - 396 - 524 - 356 - 401 - 408 - 398 - 373 - 440

Sarc

ina

Q

[nC

]

Q1 - 474 - 446 - 482 - 620 - 582 - 583 - 594 - 634 - 577 - 431

Tota

l

19,7

20,2

5

21

21,6

5

19,5

5

19,8

22,1

5

23,1

21,4

23,6

21.2

2

m2

20,6

20,5

20,7

18,1

16,7

18,6

18,7

17,4

16,8

20,9

AB

S

Mas

a m

[g]

m1

18,8

20

21,3

25,2

22,4

21

25,6

28,8

26

26,3

Tota

l

383

434 ,5

406

400 ,5

377 ,5

376 ,5

416 ,5

401

399

406 ,5

400

Q2

359

388

372

318

308

353

335

313

340

362

Sarc

ina

Q

[nC

]

Q1

407

481

440

483

447

400

498

489

458

450 Tota

l

25,4

29,1

24,8

5

29,1

25

22,6

30,1

5

28,2

27,4

5

32,1

27.3

9

m2

26,7

31,4

22,6

21,1

17,1

22,3

21,8

20,1

20

25,4

AB

S-PC

Mas

a m

[g]

m1

24, 1 26, 8 27, 1 37, 1 32, 9 22, 9 38, 5 36, 3 34, 9 38, 8

Connaissant la capacité de performance de la

machine (et les capacités de performance actuelle du processus) nous allons à comprendre que le processus peut répondre aux exigences de qualité, contribue également à l'évaluation des processus ou des appareils de collecte de données nouvelles ou modifiées et le dessin des cartes de qualité.

(1)

ou: S = écart moyen

(2)

(3) Pour les masses collectés par ABS les limites de

tolérance ont été déterminées:

(4) ou: LST = limite supérieure de tolérance;

LIT = limite inférieure de tolérance. Pour les particules électriques les limites ABS de

charge réglée de tolérance ont été::

(5)

(6)

(7)

Pour la masse collectée par les limites de la tolérance ABS-PC ont été déterminées:

(8)

Pour les particules mises en charge les limites ABS-PC de tolérance ont été:


19

(9)

CONCLUSIONS

Les applications d’Electrostatique sont souvent utilisées aujourd’hui dans de larges domaines tels que la filtration de l’air et des surfaces de peinture électro-photographique. Séparation électrostatique est le terme général donné à une classe importante de matériaux techniques de transformation, normalement utilisé pour le tri des mélanges granulaires par l’application des forces électriques qui agissent en charge ou de polarisation. Ainsi, ces techniques sont principalement utilisées pour séparer les particules sèches.

La technologie utilise dans la recherche est la technologie de séparation en „corona champ” est ainsi fixé pour l’élimination des débris de fil pour obtenir le débris tribo-electrostatique. La séparation est utilisée lorsque les déchets DEEE représentent un composé de deux types de matières plastiques ou des impuretés qui sont, par nature, non-conducteur.

Pour étudier la robustesse de la méthode Taguchi a été utilisé une installation a une plus petite échelle, qui utilise le même principe d’electro-separation Tribo-electrique. Les résultats montre la validité de la méthode.

REFERENCES [1] Dascalescu, L., “Mouvements des particules conductrices

dans un séparateur à haute tension pour matériaux granulaires“, Journal of Electrostatics, Volume 32, Issue 3, May 1994, Pages 305-316

[2] Tilmatine, A., Medles K., Bendimerad SE., Boukholda F., Dascalescu L., Electrostatic separators of particles: Application to plastic/metal, metal/metal and plastic/plastic mixtures, Waste Management, Volume 29, Issue 1, January 2009, Pages 228-232

[3] Dascalescu L, Iuga A., Morar, A. Neamtu V., Suarasan I., Samuila A, Rafiroiu D., Corona and electrostatic electrodes for high-tension separators, Journal of Electrostatics, Volume 29, Issue 3, June 1993, Pages 211-225

[4] Tilmatine, A, Flazi, S., Medles, K., Ramdani, Y., Dascalescu, L. Séparation électrostatique: complément des procédés mécaniques de recyclage des déchets industriels Journal of Electrostatics, Volume 61, Issue 1, May 2004, Pages 21-30.

Quick Info Cut cycle times for sintered parts by more than a half Superabrasive machining technology is drastically reducing the cycle times for producing parts manufactured from sintered metals.

Sintered metals are used increasingly in the automotive industry, due to the requirement for vehicles to go longer intervals between services. As a result, there is a move away from engine drive technology based on rubber belts and pulleys, to

chain drives and sprockets. It is precisely these latter components - and gears - where sintering comes into its own. The technology offers the advantage that it can be tailored to suit all requirements, enabling it to become established as a highly efficient and economical manufacturing process.

Although valued for their homogeneous and stress-free composition, materials that have undergone the sintering process are notoriously difficult to machine and are totally unsuitable for conventional turning.

However, the High Efficiency Deep Grinding (HEDG) techniques provided by Holroyd's Edgetek machines (Fig. 1) are an effective answer to this problem.

This superabrasive machining technology (is

drastically reducing the cycle times for producing automotive parts manufactured from sintered metals, in one case from 1 minute 10secs per component to just 22 seconds.

Holroyd's Paul Hannah explains: "The use of an Edgetek SAT (Superabrasive Turning System) has enabled one automotive manufacturer to machine


20

powdered metal timing sprockets and reduce tooling costs by 75 per cent as a result of the ability of Edgetek's ability to perform interrupted cuts successfully."

"In another automotive application a sintered triple drive sprocket was extremely difficult to turn conventionally due to the requirement for interrupted cuts. Previously, our customer was using tooling with CBN inserts costing from 50 to 75 dollars each. These were turning each sprocket groove in 1 minute 10 seconds, but were lasting only a maximum of 50 components, resulting in a consumable parts cost of around $1US. Machining the same component on one of our Edgetek SAT machines has reduced the cycle time from one minute 10 seconds to just 22 seconds. Moreover, throughput has been increased greatly to 15000 components per CBN wheel (costing US$500), and set-up and consumable parts costs have been reduced commensurately, the latter to just 3.3 cents per component".

In addition to sintered sprockets and gears, the Holroyd Edgetek machines provide unparalleled levels of productivity in the manufacture of rotors and impellers, medical instruments, hand tools, air foils, nozzle guides, airframe actuation components, ducting supports, mechanical seals and many more. These components are often manufactured from among the most difficult to machine materials available, including Ceramics, Nickel, Tool Steel, Waspalloy, Inconel, Hastelloy and Stellite.

The flexibility of the design and the wide range of configurations available enable the Holroyd Edgetek machines to serve the broadest spectrum of industry types, including power generation, automotive, aerospace, medicals, tools and general engineering. The machines can be tailored by Holroyd to suit specific applications and be supplied as complete turnkey solutions as part of a manufacturing cell.

Holroyd has expanded its technical support team and introduced a new product-wide support structure to help customers get the best from their machines in terms of performance, reliability and whole life costs.

All areas of production and machining using Holroyd machine tools are also subject to a pro-active approach to improved tooling and software, from updates to retrofits, upgrades, service, maintenance, preventative maintenance and breakdown support.

The introduction of the technical support team is an answer to the production pressures of a highly competitive global manufacturing base. It provides a mechanism whereby customers can ensure that their production can be maintained at its most efficient and profitable level.

Advice and support for any production or service issues can be dealt with quickly and efficiently by Holroyd's experienced mechanical, electrical, software and commissioning Engineers who, between them, are able to provide the ideal

solution, regardless of when the need arises, or how complicated the issue.

The experience of the team means that often a phone call is enough to solve an issue with any machine. This is because the engineers have been involved in the design, operation and set up of all Holroyd machines, providing a pool of knowledge and experience that customers can draw upon at any time of the day or night.

In cases where problems cannot be resolved over the phone, Holroyd engineers are able to travel at short notice to ensure that machines are returned to full production as soon as possible. This is also the primary objective in cases where the onsite work involves complex retrofitting and upgrade work, which is undertaken by Holroyd's experienced team and fully guaranteed.

The technical support team also helps companies to maintain competitiveness, by providing advice on new tooling and software developments. Holroyd is in the unique position of employing the same machines in its own production as it sells to the world market. This means that the company is always at the leading edge of tooling and software developments, providing an ongoing database of manufacturing experience, which benefits users of Holroyd products worldwide. The dynamic nature of the database enables Holroyd to offer the latest advice and solutions on any tooling issue, and also on the latest developments in machine code and profiling software which are available to customers.

Complementing the technical, support and maintenance facilities provided by Holroyd's new team is direct access to all stocked parts for Holroyd and Edgetek machines. This facility is crucial in breakdown or pressurised maintenance situations, allowing replacement parts to be despatched the same-day to restore production or to meet tight maintenance deadlines.

Commenting upon the introduction of the new service, Paul Hannah, said: "Holroyd is constantly developing the capability of its machines to ensure that they offer performance that is comparable to, or better than, any in the world. However, the fast moving nature of the global manufacturing economy means that new barriers are being broken all the time, bringing improvements in manufacturing that our technical support team can provide to our customers.

At the same time, the need to ensure maximum uptimes for production means that we are always looking at ways to improve our service. The combination of our best technical engineers into a elite support group seems to us a good way of achieving this."

Holroyd is based in Milnrow, Rochdale, England. www.holroyd.com. (source: http://www.engineerlive.com/Asia-Pacific-Engineer/Materials_Solids_Handling/Cut_cycle_times_for_sintered_parts_by_more_than_a_half/21760/)

TEHNOLOGIA INOVATIVA – Revista „Construcţia de maşini” nr. 4 / 2010

21

ETUDE EXPERIMENTALE SUR LE COMPORTEMENT RHEOLOGIQUE DES HUILES PROCESS F913

ET CASTROL MAGNATEC DIESEL

Guillaume Grandviennot *, Alexandru Rădulescu **

* Ecole Nationale D’Ingenieurs de Tarbes, FRANCE ** Université “POLITEHNICA” Bucarest, ROUMANIE

RESUME L’article propose d’analyser le comportement rhéologique des lubrifiants utilisés dans la lubrification des moteurs automobile. Les propriétés considérées sont le modèle rhéologique du lubrifiant en état frais et utilisé (avec une degré d’usure) et la variation de la viscosité avec la température pour divers gradients de vitesse imposée. Pour ces propriétés, on a déterminé par la méthode de l’analyse de régression, les lois de variation des paramètres considérés, et aussi les intervalles de confiance.

MOTS CLES: Rhéologie, Lubrifiants, Usure.

1. INTRODUCTION

La rhéologie est née de l’existence de matériaux de natures très différentes (caoutchoucs, plastiques, peintures, lubrifiants, asphalte etc.), à la déformation et à l’écoulement très éloignés de ceux d’un solide hookéen élastique ou d’un liquide newtoniens visqueux, [1], [2]. Par définition, le sujet d’étude de la rhéologie porte sur la matière en général, des solides élastiques hookéens aux liquides newtoniens visqueux.

En pratique, la rhéologie s’intéresse plus particulièrement aux matériaux dits « complexes » dont le comportement se situe entre ces deux extrêmes. La graisse, par exemple, s’écoule avec des noyaux stagnants: ce matériau est un fluide à seuil, qui est liquide lorsque la contrainte appliquée dépasse un certain seuil de contrainte, mais solide si la contrainte ne dépasse pas ce seuil, [3]. Autre exemple, les huiles additivées voient leur viscosité diminuer avec le temps (thixotropie) et avec le taux de cisaillement (rhéofluidification), au contraire de l’eau dont la viscosité reste constante, [4].

Ce papier d’analyser le comportement rhéologique des lubrifiants utilisés dans la lubrification des moteurs automobile. Les propriétés considérées sont le modèle rhéologique du lubrifiant en état frais et utilisé (avec une degré d’usure) et la variation de la viscosité avec la température pour divers gradients de vitesse imposée. Pour ces propriétés, on a déterminé par la méthode de l’analyse de régression, les lois de variation des paramètres considérés, et aussi les intervalles de confiance.

2. METHODOLOGIE EXPERIMENTALE

Le banc d’essai expérimental a été un viscosimètre rotatif Brookfield cône-plateau. Le liquide est ici placé entre un cône et un disque, l’un tournant, l’autre immobile. L’avantage de cet appareil est que pour de grands angles d’ouverture du cône (Figure 1), la vitesse de déformation est constante dans tout l’entrefer. Le viscosimètre est adapté pour l’acquisition numérique des données et offre la possibilité de déterminer la variation de la viscosité avec la température.

Fig.1. Géométrie du cône

Pour la détermination du modèle rhéologique du lubrifiant en état frais et utilisé (avec une degré d’usure) on a utilise un test de type « gradient de vitesse impose », avec les limites de variation de (100 … 2000) s-1 et une température de référence de 22 0C.


22

Le tests ont été effectués avec une chargement jusqu'à 2000 s-1 et un déchargement jusqu'à 0 s-1, afin de mettre en évidence les effets de thixotropie du lubrifiant.

Les fluides testés sont : IGOL PROCES F913 5W-30 et Castrol Magnatec Professional B4 5W-40.

Le premier huile est un lubrifiant nouvelle

génération pour les moteurs, essence et Diesel avec ou sans filtre à particules, qui convient aussi pour les biocarburants. Les propriétés physique et chimique de cette huile sont: - Viscosité à 40°C (ASTM D445): 67.3 mm²/s ; - Viscosité à 100°C (ASTM D445): 11.9 mm²/s; - Indice de viscosité (NF T 60-136): 175; - Point d’écoulement (ASTM D97): 33°C; - Point d’éclair (ASTM D92): 232°C.

Le deuxième huile a été formulée pour

répondre aux exigences les plus sévères de la plupart des constructeurs internationaux, pouvant être utilisé aussi pour les moteurs essence où Diesel. C’est un lubrifiant amélioré pour davantage d'économies de carburant, avec une longévité moteur exceptionnelle. Les propriétés physique et chimique de cette huile sont: - Masse volumique à 15°C (ASTM D4052): 0.848

g/ml; - Apparence (Visuel): Clair et limpide; - Viscosité à 40°C (ASTM D445): 82 mm²/s ; - Viscosité à 100°C (ASTM D445): 13.9 mm²/s; - Indice de viscosité (NF T 60-136): 174.

On a teste les deux fluides et on a calculé à

l’aide du logiciel du rhéomètre les paramètres rhéologique des lubrifiants selon le modèle caractéristique pour les fluides non-Newtoniens, la loi de puissance:

n

dydum

=τ (1),

avec: m – indice de consistance (équivalent avec la viscosité pour un fluide newtonien); n – indice d’écoulement (égale avec 1 si le fluide est newtonien).

Pour la détermination de la loi de variation de la viscosité avec la température pour le lubrifiant considère, on a fait les essais seulement pour le lubrifiant en état frais, avec un gradient de vitesse imposée: 500s-1 et pour une plage de températures de 5 … 75 0C.

Les plus utilisées lois de variation de la viscosité avec la température sont : • La formule de Reynolds :

( )e 0T-T-0

βηη = (2), où η0 est la viscosité à une température de référence T0 et et β est un paramètre.

• La relation de Slotte :

( )mcTT

a−

=η (3),

où Tc est la température de gèle et a est un paramètre.

• Le modèle de Yarchow et Theissen :

T+-Tb

50 9550

eηη = (4),

où η50 est la viscosité à la température de 50 0C et b est un paramètre.

3. RESULTATS

3.1 Paramètres rhéologiques

Les rhéogrames du lubrifiant en état frais et

utilisé (avec une degré d’usure) sont présentés dans les Figures 2 et 3 pour l’huile Procès F913 et les Figures 4 et 5 pour l’huile Magnatec diesel.

Les résultats pour les paramètres rhéologiques (régression à partir du modèle de Newton et du modèle loi de puissance) des lubrifiants en état frais et utilisé (avec une degré d’usure) sont obtenus directement à l’aide du logiciel intégré dans le rhéomètre (Capcalc32) et ils sont présentés dans le Tableau 1.

100 1000Shear Rate (1/sec)

10.0

100

She

ar S

tress

(N/m

²)

Brookfield Engineering LabsAnalysis Plot: Power Law File: 5W30_fraiche

Consistency Index = 0.108 Pa·s Flow Index = 0.968 Confidence of Fit = 90.1 %

Raw DataFitted Curve

Fig.2. Rhéograme du l’huile IGOL PROCES F913 5W-30 en état frais


23


10.0

100

She

ar S

tress

(N/m

²)

Brookfield Engineering LabsAnalysis Plot: Power Law File: 5W30_usage_stress



Fig.3. Rhéograme du l’huile IGOL PROCES F913 5W-30 avec une degré d’usure


100

She

ar S

tress

(N/m

²)

Brookfield Engineering LabsAnalysis Plot: Power Law File: 5W40_fraiche_stress



Fig.4. Rhéograme du l’huile Castrol Magnatec Professional B4 5W-40 en état frais

En analysant les résultats présentés, quelques

conclusions s’imposent : - Lors des tests, on a observé que le lubrifiant

IGOL PROCES F913 5W-30 usagé a une tendance à avoir des phénomènes d’hystérésis plus marqués que pour un lubrifiant frais. Cela peut s’expliquer par les contraintes que subies un lubrifiant lors de son usage, passage dans les engrenages, arbre à cames, et l’usure de l’huile;

- Par contre, l’autre lubrifiant Castrol Magnatec Professional B4 5W-40 ne manifeste pas cette tendance, donc il est plus stable du point de vue chimique et physique;


100

She

ar S

tress

(N/m

²)

Brookfield Engineering LabsAnalysis Plot: Power Law File: 5W40_usage_stress



Fig.5. Rhéograme du l’huile Castrol Magnatec Professional B4 5W-40 avec une degré d’usure

- Le modèle qui a le plus fort coefficient de

corrélation avec les données expérimentales est le modèle de Newton, sauf pour le lubrifiant IGOL PROCES F913 5W-30 usagé;

- Le comportement de ces fluides est presque Newtonien du fait de la similitude entre le modèle de Newton et les résultats expérimentaux, de plus la viscosité ne varie pas de façon significative pendant les changements de vitesse de rotation du banc d’essai;

- L’huile Castrol Magnatec Professional B4 5W-40 à une plus forte tendance à se rapprocher d’un fluide Newtonien par rapport à l’huile IGOL PROCES F913 5W-30.

3.2 Paramètres thermiques

Les résultats concernant la variation de la

viscosité avec la température pour le lubrifiant en état frais, pour les gradients de vitesse imposée: 500 s-1 et pour une plage de températures de 5 … 75 0C sont présentés dans les Figures 6, 7, 8 et 9. Afin de déterminer les paramètres caractéristiques pour les lois de variation de la viscosité en fonction de la température, on va utiliser le software Excel pour traiter toutes les données, les résultats étant présentés dans le Tableau 2.

On remarque que le lubrifiant IGOL PROCES F913 5W-30 n’as pas la même courbe de viscosité entre son état usé et frais, ce qui n’est pas le cas du lubrifiant Castrol Magnatec Professional B4 5W-40 qui garde ses même propriétés. Cette différence peut être expliquée par le fait que l’huile Magnatec n’a pas été utilisée avec la même intensité que l’huile F913. La différence de viscosité entre un lubrifiant frais et usagé, est peut être du aux divers choques thermique qu’il a subit et l’usure mécanique de celui-ci.


24

Tableau 1. Paramètres des modèles rhéologiques

Modèle de Newton Loi de puissance

Type du lubrifiant Viscosité (η), Pa·s

Coefficient corrélation

Indice de consistance (m), Pa·sn

Indice d’écoulement

(n)

Coefficient corrélation

IGOL PROCES F913 5W-30

(frais) 0,0836 94% 0,108 0,968 90%

IGOL PROCES F913 5W-30

(usagé) 0,0637 77% 0,109 0,926 79%

Castrol Magnatec Professional B4 5W-40

(frais) 0,1286 98% 0,230 0,921 97%

Castrol Magnatec Professional B4 5W-40

(usagé) 0,127 98% 0,274 0,895 97%

Les différents modèles de régression correspondent parfaitement au modèle expérimental. On ne peut pas dégager de réels avantages à choisir un modèle plutôt qu’un autre puisqu’ils sont tous précis. La comparaison entre les résultats de la régression numérique et les résultats expérimentaux est toujours présentée dans les Figures 6, 7, 8 et 9.

Fig. 6. Comparaison des modèles F913 frais

Fig. 7. Comparaison des modèles F913 usagé

Fig. 8. Comparaison des modèles Magnatec frais

Fig. 9. Comparaison des modèles Magnatec usagé


25

Tableau 2. Valeurs principales pour les paramètres thermiques des huiles étudiés

Modèle de Jarchov et Theissen Paramètre Huile η50, Pa⋅s B Coeff. de

corrélationF913 frais 0,032 4,947 99,62%

F913 utilisé 0,022 5,163 99,42% Magnatec frais 0,047 5,040 99,57% Magnatec utilisé 0,048 4,896 99,77%

Modèle de Slotte Paramètre Huile a, Pa⋅s m, 0C-1 Coeff. de

corrélationF913 frais 17530 3,0189 99,37%

F913 utilisé 24048 3,1818 99,10% Magnatec frais 17303 2,918 99,42% Magnatec utilisé 10321 2,787 99,69%

Modèle de Reynolds Paramètre Huile η50, Pa⋅s m, 0C-1 Coeff. de

corrélationF913 frais 0,030 0,0424 99,60%

F913 utilisé 0,020 0,0452 99,80% Magnatec frais 0,040 0,0449 99,77% Magnatec utilisé 0,045 0,0418 99,48%

4. CONCLUSIONS • On a déterminé les paramètres rhéologiques du

lubrifiant et on a constate une différence entre les caractéristiques des lubrifiants frais et utilisé surtout pour le F913.

• Lors des tests, on s’est rendu compte qu’un lubrifiant moteur usagé avait tendance à avoir des phénomènes d’hystérésis plus marqués que pour un lubrifiant frais. Cela peut s’expliquer par les contraintes que subies un lubrifiant lors de son usage, passage dans les engrenages, arbre à cames, et l’usure de l’huile. Cependant ce phénomène existe aussi pour un lubrifiant frais.

• Le comportement du lubrifiant, en état frais ou utilisé est presque newtonien. En effet la loi de comportement théorique de Newton se rapproche le plus des valeurs expérimentales. On peut aussi ajouter que la viscosité ne varie pas de façon significative au pendant les changements vitesse de rotation du banc d’essai.

• Tous les trois modèles analysés pour la variation de la viscosité en fonction de la température sont valables.

BIBLIOGRAPHIE 1. Barnes, H. A., Hutton, J. F. and Walters, K. An

introduction to rheology. Elsevier, 1989. 2. Bergenholtz, J., Brady, J. F. and Vicic, M. The non-

Newtonian rheology of dilute colloidal suspensions. J. Fluid Mech., 456 :239, 2002.

3. Coussot, P., Nguyen, Q. D., Huynh, H. T. and Bonn, D. Viscosity bifurcation in thixotropic, yielding fluids. J. Rheol., 46 :573, 2002.

4. Doraiswamy, D. The origins of rheology: a short historical excursion. Rheology Bulletin, 71(1), 2002.

5. Larson, R. G. The structure and rheology of complex fluids. Oxford University Press, New York, 1999.

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27

ESSAIS EXPERIMENTALES SUR LE COMPORTEMENT MECANIQUE DE POLYTETRAFLUORETHYLENE (PTFE)

Eugenia Costache1, Mohamed Hajjam2, Aurelian Fatu2, Alexandru Rădulescu1, Sorin Cănănău1,

1 Dep. Eléments de Machines et Tribologie, Université “Politehnica“ de Bucarest, ROMANIA 2Genie Mécanique et Systèmes Complexes, Université de Poitiers, ENSMA, FRANCE

RESUME L’article propose l’étude sur les lois de comportement des matières plastiques, et surtout pour le polytetrafluorethylene (PTFE). On a présenté les propriétés générales des plastiques, avec l’accent sur le comportement mécanique des matériaux polymères. Les essais expérimentales ont été réalisées sur une machine de traction INSTRON 4302, pour les cas de déplacement imposé et charge imposée. Les courbes obtenues ont été utilisées pour la modélisation numérique. Finalement, on a fait les comparaisons entre les résultats et on a présenté les conclusions deduites du comportement du PTFE. MOTS-CLÉ: PTFE, Traction, Module d’élasticité

1. INTRODUCTION L’histoire récente des plastiques montre que,

depuis une vingtaine d’années, les producteurs ont développé de polymères nouveaux, optimisés dans un but précise. Un polymère est un enchaînement de groupes organiques identiques appelés monomères. Un monomère est une suite d'atomes de carbone liés entre eux et avec d'autres éléments (H, Si, Cl...). On peut distinguer les homopolymères, qui représentent une répétition d'une unique structure moléculaire et les copolymères, qui désignent une répétition de plusieurs structures différentes. Ils sont classés en trois catégories, [1]: - les thermoplastiques (plastiques appelés aussi

"engineering plastics"); - les thermodurcissables; - les élastomères.

Les matières thermoplastiques pourront être séparées en polymères amorphes et partiellement cristallins (polymères industriels). La frontière entre ces deux groupes n’est pas très nette. Les matières plastiques à structure amorphe sont, généralement, transparents et ont une tendance à être sensibles aux fissures de tension. En raison de leur grande stabilité dimensionnelle, elles conviennent aux pièces de précision. On constate, au cours de leur chauffage à température croissante, qu’ils perdent leur rigidité et deviennent aussi déformables que des élastomères; le passage à l’état fluide se faisant ensuite de façon très progressive.

Les matières plastiques partiellement cristallines sont opaques, la plupart du temps rigides et présentent une bonne à très bonne résistance aux produits chimiques.

On peut faire une différence entre les matières plastiques en raison de leur résistance à la température. Les matières plastiques à haute température présentent une température d’utilisation permanente de plus de 150°C et possèdent un haut niveau de propriétés thermomécaniques. Les matières plastiques convenant à de plus hautes températures d’application (PI, PBI, PTFE) ne peuvent techniquement pas être traitées par fusion. La fabrication de pièces se fait par frittage.

Les matières plastiques de construction peuvent être utilisées en permanence à des températures entre 100°C et 150°C. Elles présentent de bonnes propriétés mécaniques et une bonne résistance aux produits chimiques. Les matières plastiques standard peuvent être utilisées en permanence à des températures inférieures à 100°C. La pyramide de matières plastiques représentées ci-dessous montre, sur la base de ces critères, une vue générale détaillée des matières thermoplastiques (Fig. 1). Elle donne une idée de la zone d'utilisation des thermoplastiques. Au-delà de 300°C, on passe à d'autres produits à base de résines spéciales, de silicates etc, [2], [3].


28

Fig. 1. Répartition des matières plastiques, [1]

2. PROPRIETES PHYSIQUE ET CHIMIQUE DU PTFE

PTFE est une matière plastique au fluor

résistant aux hautes températures. Cette matière est typique par son excellent comportement antiadhésif. Le frottement des matières plastiques contenant du PTFE forme sous la pression un film polymère de glissement au niveau des surface en contact l’une avec l’autre.

La chaîne de PTFE a une conformation hélicoïdale, les atomes de fluor ont un diamètre de Van der Waals de 0,270 nm. Cette structure (Fig. 2), entraîne une rigidification considérable de la chaîne, aussi bien à l'état cristallin qu'à l'état liquide. La chaîne de PTFE ressemble à une barre cylindrique et rigide avec une surface lisse, [2].

Fig. 2. Structure hélicoïdale de la chaîne de PTFE, [2]

Le PTFE est un des matériaux thermoplastiques les plus stables. A 280° C, on ne peut remarquer que très peu de traces de décomposition de telle sorte qu’à cette température, le PTFE garde la plupart de ses propriétés. Le PTFE commence réellement à se décomposer au-dessus de 400° C. Le coefficient de dilatation linéaire varie avec la température. De plus, suite à un changement de forme dû à un usinage par exemple, les pièces finies deviennent souvent anisotropes. Cela veut dire que le coefficient de dilatation pourra aussi varier suivant la direction géométrique. Le coefficient de conductibilité thermique ne varie pas avec la température. Il est relativement bas, de telle sorte que le PTFE peut

être considéré comme un isolant. L’ajout de charges modifie de manière parfois importante cette propriété. La chaleur spécifique, ainsi que l’enthalpie augmente avec la température.

Le PTFE est pratiquement inerte vis-à-vis de tous les produits connus. Il ne peut être attaqué que par des métaux alcalins fondus. De plus, ce risque n’existe pas que sous haute pression et haute température. Le PTFE est insoluble dans la plupart des solvants et jusqu’à des températures de 300°C.

Les hydrocarbures fluorés provoquent un léger gonflement toutefois réversible. Certaines huiles hautement fluorées et à des températures supérieures à 300°C, peuvent provoquer une dissolution partielle du PTFE. Du point de vue des propriétés mécaniques, ceux ci sont fortement influencés par les conditions de travail (température) et également par la qualité de la résine de base employée pour fabriquer le produit semi-fini. Le PTFE peut, dans tous les cas, être utilisé de manière continue jusqu’à 260°C, tandis que des températures proches du zéro absolu provoque une perte de résistance à la compression. Si une pièce en PTFE est soumise à des tensions ou à la compression, même au dessous de la limite de rupture, il peut en résulter des déformations rémanentes importantes, avec comme conséquence, des tensions internes induites. Si on réchauffe la pièce, ces tensions auront tendance à disparaître et la pièce reprendra une forme proche de sa forme originale. Cette propriété du PTFE est souvent appelée la «mémoire plastique» et est utilisée dans des applications bien spécifiques, [2]. Les propriétés semi-finies en PTFE possèdent un certain niveau de tensions internes. Ceci est du au mode de transformation de la résine, depuis son état de poudre jusqu’à la plaque ou la barre utilisable. Si on désire disposer de matériaux semi-finis stables dimensionnellement à haute température, il est possible d’y arriver. Il suffit de porter le bloc ou l’ébauche en PTFE à une température de 280°C et de l’y maintenir durant 1h (par 6mm d’épaisseur) et d’ensuite, le laisser refroidir lentement. En procédant de la sorte, le matériau sera complètement libéré de ses tensions internes et sera dit « thermostabilisé » ou « conditionné », [3].

En ce qui concerne les propriétés tribologiques, le PTFE possède le coefficient de frottement le plus bas de tous les matériaux solides. La valeur se situe entre 0.05 et 0.09. Le coefficient de frottement en statique et en dynamique est quasi identique. Cela veut dire qu’on n’observe pas de phénomène de « stick-slip ». Lors d’un accroissement de charge, le coefficient de frottement va diminuer jusqu’à atteindre une valeur stable. Le coefficient de frottement augmente avec la vitesse et il reste constant lors de variations de température, [4].


29

2. PRESENTATION DU BANC D’ESSAI

Les systèmes d'essais de table de INSTRON 4302 conviennent idéalement aux essais de force inférieure à 50 kN nécessitant un alignement précis ou pour tester les grandes éprouvettes (Fig. 3).

Ces systèmes utilisent l'électronique d'acquisition et de commande la plus performante et le logiciel Musicx normalisé dans l'industrie. Ces systèmes peuvent être équipés d'une vaste gamme de mâchoires et d'accessoires pour les essais de traction, de compression, de flexion et sur composants. Les accessoires disponibles comprennent des extensomètres pour la mesure des déformations et des enceintes climatiques pour les essais à températures variées.

Une des caractéristiques de ce banc d’essai c’est la grande précision de la charge affichée, il présente aussi une très large plage de meure de force, une acquisition des données ultra-rapide 5000Hz, synchrone sur tous les canaux, un panneau de commande manuelle étudié pour le confort de l’opérateur. On a une bibliothèque de méthodes d'essai ASTM et ISO et l’architecture est ouverte pour programmation d’essais.

Fig. 3. Banc d’essai expérimental

On utilise généralement une éprouvette plane, de faible épaisseur, de forme axisymétrique avec un profil en sablier, les parties gauche et droite de cette éprouvette sont soumises à une traction (Fig. 4).

Les contraintes et les déformations sont supposées homogènes dans la partie centrale du

corps de l’éprouvette. Afin d’interpréter les expérimentes, il est nécessaire de connaître la loi de comportement du matériau, c’est-à-dire l’évolution de la contrainte de traction σ avec la déformation ε, et la vitesse de déformation, à la température T.

Fig. 4. Eprouvettes expérimentales

3. RESULTATS EXPERIMENTALES

Pour les expérimentes mécaniques, on a utilisé quatre éprouvettes de PTFE avec les mêmes caractéristiques (Tab.1). Dans le cas des PTFE, la contrainte à la limite élastique, module d'élasticité, résistance et leur allongement sont élevés.

Sous l'effet d'un étirage, la plupart des polymères de ce groupe subissent un écoulement à froid qui produit une striction dans l'éprouvette. L'étirage à froid améliore la résistance et constitue donc un procédé très important de la technologie des fibres synthétiques. Tab. 1. Caractéristiques des éprouvettes

Epaisseur [mm] 0.59 Largeur [mm] 5 Longueur [mm] 14 Température [°C] 20°C

On a fait deux types d’essais : - à vitesse de déplacement imposé ; - à charge imposée.

Pour chaque essai, on a tracé la courbe contrainte-déformation. Pour l’essai à vitesse de déplacement imposé, on peut observer que la courbe est formée de trois parties. Par le pante initial, (Fig. 5), on peut déterminer la valeur du module d’Young (module d'élasticité) en introduisant une courbe de tendance (Fig. 6).


30

Fig. 5. Test à vitesse de déplacement imposé

Sur la première partie du graphique, on peut observer que le PTFE a un comportement élastique pour une déformation de 0,04 %, et la deuxième partie montre une viscoplasticité très prononcée. Après cet essai, le PTFE, a changé de forme et aussi de couleur dans la zone qui a souffert des déformations.

Fig. 6. Courbe de tendance pour le test à vitesse de déplacement imposé

Dans le Tableau 2, on a présenté la valeur de

module de Young qu’on a obtenu pour tous les quatres éprouvette testées.

Tab. 2 Valeurs de module de Young

Des essais suplémentaires on été faites pour étudier l’influence de la vitesse de traction sur le module de Young du PTFE (Fig. 7).

Fig. 7. Comparaison entre les essais au déplacement imposé

Les courbes en rouge et bleu représentent les

essais faites à la vitesse de 8.45mm/s et celles en rose et vert à 1.25mm/s. Quand le PTFE atteint la limite d’élasticité, on entre dans la zone de viscoélasticité, où on peut remarquer que la contrainte augmente avec la déformation, jusqu’au moment où il entre dans la zone de relaxation.

En ce qui concerne les essais à charge imposée, on a réalisé l’essai de fluage. Il consiste à imposer de façon instantanée en traction, compression uniaxiale où flexion, une contrainte constante σ0 à une éprouvette et à suivre ses déformations en fonction du temps.

Les résultats sont généralement exprimés sous forme d’une courbe de fluage: déformation-temps [ε(t)-t], où comme il s’agit d’essais de longue durée sous forme d’une courbe [ε(t)-lg t] (Fig. 8).

Fig. 8. Courbe de fluage (déformation-temps)


31

On distingue la déformation instantanée ε0=0.062% et si, au temps t1=2122s on supprime la charge appliquée, on observe une courbe de décharge faisant apparaître une recouvrance élastique et une recouvrance viscoélastique ou retardée.

4. CONCLUSIONS

Si une pièce en PTFE est soumise à des tensions ou à la compression, même au dessous de la limite de rupture, il peut en résulter des déformations rémanentes importantes, avec comme conséquence, des tensions internes induites. Si on réchauffe la pièce, ces tensions auront tendance à disparaître et la pièce reprendra une forme proche de sa forme originale. Cette propriété du PTFE est souvent appelée la «mémoire plastique» et est utilisée dans des applications bien spécifiques.

L’essai de traction c’est l’essai fondamental de tous les essais mécaniques. Cet genre d’essai sert à déterminer les principales caractéristiques mécaniques comme: le module d’élasticité, la limite d’élasticité, résistance à la rupture. Son exécution est facile et les résultats qu’on obtient aident à dimensionner tout sorte de pièces.

Dans le cas des PTFE, la contrainte à la limite élastique, module d'élasticité, résistance et leur allongement sont élevés. Après les essais, le PTFE, a changé de forme et aussi de couleur dans la zone qui a souffert des déformations.

BIBLIOGRAPHIE

1. Petitet, G. and Barquins, M. Matériaux caoutchouteux Morphologies, formulation, adhérence, glissance et usure, Presses polytechniques et universitaires romande, 2008

2. Moore, D. F. Viscoelastic machine elements. Elastomers and lubricants in machine systems, Butterworth-Heinemann Ltd., 1993

3. Chatain, M. Comportements physique et thermomécanique des plastiques, http://delagrave. flammarion. com/docs/Albums/36276/Annexe_143.pdf

4. Sui, H., Pohl, H., Schomburg, U., Upper, G. and Heine, S. Wear and friction of PTFE seals, Wear, Volume 224, Issue 2, 1999, pp. 175-182

Quick Info

CAD package benefits from additional features Bricsys is releasing Bricscad V11 for Windows, the latest edition of this popular CAD package for working with .dwg files. With Bricscad V11, Bricsys says it is adding numerous key features. According to Bricsys, Bricscad's level of .dwg compatibility, together with the availability of a growing number of third-party applications (currently more than 160) makes Bricscad the best alternative to other .dwg packages.

Bricscad V11 includes support for editing dynamic blocks; dynamic blocks can be inserted from existing Dynamic Blocks Libraries, and properties and constraints can be adjusted in the Properties Bar. PDF files can be used as an underlay and Bricscad V11 enables snapping to the geometry of the PDF entities. Bricscad V11 also has a useful Layer Preview; in the layer section of the Drawing Explorer, the content of each layer displays in the preview pane. The Graphical User Interface is now enhanced with support for new style Grips, Dynamic Input and Dynamic Dimensions. This is a significant improvement in the interface and makes drawing in Bricscad more direct and more dynamic. Bricscad V11 Pro benefits from the powerful Redway3D rendering engine, allowing rendering in permanent mode. This rendering technology is said to be one of the fastest in the industry. Lights and materials can be defined in the Drawing Explorer, and settings to define materials allow detailed fine-tuning. Erik De Keyser, CEO of Bricsys, states: "With Bricscad V11 we continue to add value for our hundreds of thousands of users worldwide. Thanks to the wide acceptance of our APIs in the application community we can offer now an unmatched range of functionality in all the main disciplines of engineering. Our focus is the balance between compatibility, performance and price." Bricscad V11 Classic for Linux is on its way and will be released very shortly. It will contain all the same new features as the Bricscad V11 Classic for Windows version. eBridge will also be available for Bricscad V11 for Linux users. For more information, visit www.bricsys.com (source: http://www.engineerlive.com/Design-Engineer/Computer_Systems_Software/CAD_package_benefits_from_additional_features/23118/)


32

CAD software available on a software-as-a-service basis

Ascon Group and Cloud IT are now offering the mechanical computer-aided design (MCAD) software package Kompas-3D on a SaaS (software as a service) basis, currently on the territory of Russia and CIS countries, but shortly in other regions too. The key benefits of CAD software acquired and used on this basis are: * No need to install the software at customer workplaces * High productivity at any equipment * Complete independence from any software platform * Absolute mobility * Opportunity to use just required applications in any quantity * Considerable savings in IT costs at the enterprise * Ability to use software in virtual offices * Participation in temporary projects without permanent investments * Opportunity to migrate to alternative operating systems Today a wide range of standard office applications are available on a SaaS basis, including mail services and security. However, the availability of high-end software has been extremely limited. Now Cloud IT, acting as the service provider, is working with CAD developer and integrator Ascon Group with the aim of offering access to CAD on a SaaS basis.

Oleg Zykov, Ascon's innovations projects manager, comments: "From an IT specialist's point of view we do not offer anything unique - all the technologies are well known. We just put them together and gave a new value for the customers. It was impossible yesterday to buy CAD for a two-month term for a temporary project, or to install Kompas on a PC with Linux and work with CAD data on an iPad during a business trip. But now all of these abilities come true." Ascon products are deployed on a Cloud IT server, which will interact with users of the service. CEO of Cloud IT, Igor Gonebniy, comments on the conditions and perspectives for the co-operation: "Our aim at the project is to provide the platform for the software developer, support them with all the necessary services, security and billing. At our capacity will be deployed more than ten different configurations of Kompas-3D and it will be possible to pay for them monthly." From 1 October 2010 the service is available in Russia and CIS countries, but the ability to purchase Kompas software on a SaaS basis for international users is coming soon. For more information, visit http://ascon.net (source: http://www.engineerlive.com/Design-Engineer/Computer_Systems_Software/CAD_software_available_on_a_software-as-a-service_basis/23119/)


33

ELECTROCOMPOSITE WITH ZINC ALLOYS MATRIX AND AL2O3 NANOPARTICLES

R.Stancu1, Gh. Badea2, G. Diacov2, M. Hriscu2, D. Ciupitu3, E. Alexandrescu3 1Scoala cu clasele I-VIII 162, Bucharest, Romania, [email protected] 2S.C.ICTCM S.A , Bucharest, Romania, [email protected] 2S.C.ICTCM S.A , Bucharest, Romania, [email protected] 2S.C.ICTCM S.A , Bucharest, Romania, [email protected] 3S.C.METAV Cercetare Dezvoltare, Bucharest, Romania, [email protected]

REZUMAT Lucrarea prezinta date experimentale privind acoperirile nanocompozite cu matrice metalica Zn-Fe(1-3%) si Zn-Ni(7-15%) si nanoparticule ceramice de oxid de aluminiu. Depunerile au fost obtinute din electroliti alcalini. A fost studiat efectul concentratie de particule asupra rezistentei la coroziune. Caracterizarea structurii s-a realizat utilizand microscopul electronic, care a pus in evident structura nanocristalina a depunerii.

ABSTRACT This paper presents experimental date regarding nanocomposite coatings with Zn-Fe(1-3%) and Zn-Ni(7-15%) metallic matrix and ceramic nanoparticles of aluminium oxide. Deposits were obtained using alkaline electrolytes. The effect of different concentration of particles on corrosion resistance was studied. Structural characterization using scanning microscopy showed that the deposits are nanocrystalline.

CUVINTE CHEIE: electrodepunere, nanocompozite, aliaje de zinc cu Al2O3, aliaje de zinc, depuneri rezistente la coroziune

KEYWORDS: electrodeposition, nanocomposites, zinc alloys with Al2O3, zinc alloys, corrosion resistant deposits

1. INTRODUCERE

Progresul continuu in industria acoperirii

metalelor in intreaga lume cauta sa raspunda cat mai bine problemelor de coroziune. Depunerile de aliaje de zinc cu cobalt, fier sau nichel sunt utilizate ca depuneri protectoare si decorative. [1, 2] Aceste depuneri au o rezistenta la coroziune marita comparative cu depunerile de zinc pur. [3, 4] Concentratia in fier in aliaj este de numai1-3%, comparativ cu depunerile de Zn-Ni unde concentratia in nichel este de ~ 15% Ni.[5]

Aplicatiile nanocompozitelor electrochimice sunt date atat de matricea metalica cat si de faza dispersa. Astfel pe langa proprietatile anticorozive ale matricei de metalice Zn-Fe si Zn-Ni s-a incercat imbunatatirea rezistentei la coroziune prin includerea de nanoparticule de Al2O3.

2. ELECTRODEPUNERE Zn-Ni-Al2O3 ŞI Zn-Fe-Al2O3

S-a urmarit obtinerea aliajelor de Zn-Fe(1-

3%) si respective Zn-Ni(7-15%). In electrolitii alcalini dezvoltati s-a adaugat suspensie de oxid de aluminiu. Influenta concentratiei nanoparticulelor de Al2O3 asupra compozitie si structurii depunerii composite, precum si rezultatele testelor de ceata salina la care a fost supusa acoperirea nanocompozita vor fi prezentate in continuare.

3. EXPERIMENTARI

Compozitia si comditiile de depunere pentru

electrolitii alcalini sunt prezentate in tabelul 1. Solutiile au fost preparate cu substante p.a. utilizand apa distilata. Mentinerea particulelor in suspensie s-a


34

realizat folosind un agitator magnetic, viteza de rotatie fiind de 7 rot./minut.

Depunerile s-au realizat pe substart de otel, iar ca anod a fost utilizat otel. Depunerile au fost supuse urmatoarelor teste: microscopie electronica, difractie de raze X, rezistenta la coroziune. Tabel 1 – Compozitia chimica, conditiile si parametrii de lucru pentru obtinerea depunerilor de nanocompozite electrodepuse

Nr. Crt.

Tip depunere

Compozitia chimica a electrolitului

Concentratia

1 Zinc - Fier

Oxid de zinc Hidroxid de

sodiu Adaos AN 31 Complex de

fier Suspensie

Al2O3

10-12 (g/l) 125-130 (g/L) 3 – 12 (ml/L) 1 – 3 (ml/L) 10-20 (ml/L)

2 Zinc - Nichel

Oxid de zinc Hidroxid de

sodiu Adaos AN 31 Complex de

nichel Suspensie

Al2O3

10-12 (g/L) 125-130 (g/L) 3 – 12 (ml/L) 5 – 10 (ml/L) 10-20(ml/L)

Figura 1. Ordine superioare de marire care fac observabile morfologia si dimensiunile particulelor

de oxid de aluminiu (a) si de zinc (b), pe stratul Zn-Fe-Al2O3 20 ml/L (x50.000; x100.000)

REZULTATE SI DISCUTII

Aspectele observate prin investigarea la microscopul electronic cu baleiaj pentru probele de Zn-Fe-Al2O3 au fost urmatoarele: • analiza structurala a monostratului prezinta particule de Zn, de dimensiuni nanometrice (30-90 nm), microparticule(100-300 nm) si nanoparticule (< 100 nm) poligonale de oxid de aluminiu, observate cu precadere pe ariile de contrast luminos si in cantitate mai mare pe proba Zn-Fe-Al2O3 10 ml/L aplicabila la nanostructuri); pe proba Zn-Fe-Al2O3 10 ml/L - microanaliza calitativa de raze X, efectuata pe sectiune, la mariri mici, a evidentiat dispunerea aluminiului in cantitati mai mari la suprafata stratului, formand aglomerari; tot in sectiune s-a observat prezenta fierului in strat,

• morfologia particulelor de zinc, observate la mariri mari (x100.000; x200.000), este sferica in cazul depunerilor Zn-Fe-Al2O3 10 ml/L si alungita in cazul Zn-Fe-Al2O3 20 ml/L; aspectul microstructurii sugereaza o crestere, pe alocuri, de tip “tesatura”, iar in alte zone crestere de tip “broccoli” caracteristica unor electrodepuneri similare; • rezultatele difractiei de raze X, adica difractogramele prezentate in Fig.4., confirma structurarea unor nanocompozite cu matrice metalica Zn, care prezinta micro si nanodomenii (i.e. Zn se regaseste sub forma de micro si nanoparticule) si faza dispersa formata din nanoparticule de Al2O3 aflate in cantitate mai mare in proba Zn-Fe-Al2O3 10 ml/L , desi proba Zn-Fe-Al2O3 20 ml/L. s-a obtinut prin electrodepunere dintr-o solutie mai concentrata in alumina (distributia in suprafata probei este inproportie de pina la 10% ).


35

Figura 2. Zn-Fe-Al2O3 20 ml/L Microstructura stratului(x5000; x20.000)

Analiza structurala (la nivel micro si nano) si analiza compozitionala microzonala (calitativa si cantitativa de RX) pentru depunerile nanocompozite Zn-Ni-10ml/L Al2O3 respectiv Zn-Ni-20ml/L Al2O3 au condus la urmatoarele rezultate:

• prezinta aspecte structurale asemanatoare intre ele si asemanatoare cu cele observate pe probele de Zn-Ni;

• pe toate probele s-a observat prezenta straturilor de acoperire, formate mai ales din particule de zinc, de dimensiuni nanometrice (aprox. 10 nm); sunt mult mai rare, insa, formatiunile de particule de oxid de zinc, semnalate la probele de Zn-Ni, iar dimensiunile acestora se situeaza intre cateva zeci si cateva sute de nanometri (Fig. 5);

• analiza EDS a detectat prezenta nichelului, prin maxime slabe, prezenta vizibila pe sectiune decat pe suprafata (Fig. 6);

• aluminiul a fost detectat tot in cantitati foarte reduse, fara sa se poata stabili o diferenta intre probele cu concentratii diferite de oxid de aluminiu; de asemenea, datorita finetii structurii, nu s-a putut observa modul de distribuire in particule a nichelului si aluminiului (la analiza EDS)-Fig. 7;

• aderenta straturilor este buna, neobservandu-se exfolieri sau discontinuitati ale acestora.

Figura.3. Particule de zinc si cristale de oxid de aluminiu, observate pe proba Zn-

Fe-Al2O3 20 ml/L (x50.000)

Figura.4. Spectru energetic -EDS emis de stratul electrodepus al proba

Zn-Fe-Al2O3 20 ml/L Se observa prezenta elementelor

O, Al, Si, S, Fe si Zn

Figura.5. Aspectul microstructurii stratului depus de Zn-Ni-10ml/L Al2O3. Particule de zinc si particule de

oxid de zinc (x10.000; x100.000)

Figura 6. Spectrul EDS obtinut pe stratului depus de Zn-Ni-10ml/L Al2O3 – sectiune. Se observa maximele

slabe ale aluminiului si nichelului


36

Testele de rezistenta la coroziune realizate in ceata salina conform ASTM B117, pentru depunerile nanocompozite nepasivate au aratat ca nanoparticulele de Al2O3 maresc rezistenta la coroziune pentru depunerile de Zn-Fe (47 ore pana la aparitia coroziunii de baza). O concentratie de 10ml/L Al2O3 in electrolit confera o rezistenta la coroziune mai mare (93 ore pana la aparitia coroziunii de baza) comparativ cu cea de 20ml/L Al2O3 in electrolit (70 ore pana la aparitia coroziunii de baza).

Depunerile de Zn-Ni nepasivate cu o concentratie de complex in baie au prezentat puncte de coroziune de baza dupa 143 ore de ceata salina, in timp ce cele cu o concentratie mai mica de complex, pana la 215 ore de ceata salina nu au prezenta coroziune de baza. Depunerile nanocompozite Zn-Ni(10ml/Lcomplex)-10ml/L Al2O3 au prezentat puncte de coroziune de baza dupa 215 ore ceata salina, comparativ cu depunerile nepasivate de Zn-Ni(20ml/Lcomplex)-10ml/L Al2O3 care au puncte de coroziune de baza dupa 98 ore de testare.

Figura 7. Imagine de electroni secundari si imagini de distributie in suprafata a intensitatii relative a radiatiei X caracteristice elementelor

detectate pe Zn-Ni-10ml/L Al2O3 – sectiune. Se observa concentrarea in strat a zincului,

nichelului, aluminiului si oxigenului

CONCLUZII

• rezultatele difractiei de raze X, au confirmat structurarea unor nanocompozite cu matrice metalica Zn-Fe-Al2O3, care prezinta micro si nanodomenii (i.e. Zn se regaseste sub forma de micro si nanoparticule) si faza dispersa formata din nanoparticule de Al2O3 aflate in cantitate mai mare in proba cu 10ml/L Al2O3, comparativ cu cea obtinuta din electrolitul cu 20ml/L Al2O3 care s-a obtinut prin electrodepunere dintr-o solutie mai concentrata in alumina (distributia in suprafata probei este inproportie de pina la 10% ); • nanoparticulele de Al2O3 maresc rezistenta la coroziune a aliajului Zn-Fe; o concentratie mai mica de suspensie in electrolit conduce la depuneri nanocompozite Zn-Fe-Al2O3 cu rezistenta la coroziune mai buna; • rezistenta la coroziune a depunerii de Zn-Ni-10ml/L Al2O3 este mai mare decat a depunerii Zn-Fe-10ml/L Al2O3; • in cazul ambelor tipuri de depuneri nanocompozite (cu matrice de Zn-Fe si Zn-Ni) o concentratie mai mica de particule de oxid de aluminiu in electrolit conduce la depuneri cu o rezistent la coroziune ma mare decat cele cu concentratie de suspensie mai mare.

BIBLIOGRAFIE

[1] E.O.S. Carpenter and J.P.G. Farr: Trans. IMF, 1998, 76, 135-143 [2] T.Tsuru, S.Kobayshi, T.Akiyama, H.Fukushima, S.K.Gogia and R.Kammel; J.Appl.Electrochem., 1997, 27, 209-214 [3] A.Brenner: „Electrodeposition of alloys: principles and practice”, vol. 1; 1963, New York, Academic Press [4] N.R. Short, J.K. Dennis and S. Zhou: Surf. Coat. Technol., 1996, 79, 218 [5] M.A. Pech-Canul, R. Ramanauskas and L. Maldonado: Electrochem Acta, 1997, 42, 255-260.


37

MODELE DE ANALIZA A NANOCOMPOZITELOR ELECTRODEPUSE

Leonard Teodoru1 , Valentin Mihailescu2 , Alexandru Ionescu3, Gratiela Epureanu4,

1,2,3,4 Foundation Professor Constantin Popovici "Bucharest, Romania [email protected], [email protected], alex.fpcp @ gmail.com, [email protected]

REZUMAT: Se prezinta modelul preliminar de analiza a nanocompozitelor electrodepuse, parametrii modelului pentru determinarea ecuatiilor matematice, tipuri de modele pentru procesul de electrodepunere. Se descrie modelul simplificat si conditiile la limita pentru submodele analizate, ipoteze simplificatoare si conditiile de care depinde depunere. ABSTRACT: It presents the preliminary analysis of electro deposited nanocomposites parameters model equations for determining mathematical models for the electronic filing process. It describes a simplified model and boundary conditions for models under consideration, the simplifying assumptions and conditions upon which the deposit.

CUVINTE CHEIE: Nanocompozite, modelare, electrodepunere

KEYWORDS: Nanocomposites, modeling, electrodeposition

1. MODELAREA MATEMATICA A NANOMATERIALELOR

Modelarea matematica a nanomaterialelor au un rol important în sprijinirea executiei şi proiectarii de noi tehnologii ale căror aplicaţii sunt in principal pentru domenii cum ar fi:

- industria transporturilor, - medicina, - telecomunicatii, - aeronautica, - electronica, - electrotehnica - ingineria mediului.

Modelul matematic permite descrierea fenomenelor electrochimice si a celor de transport masic care apar in difuzarea straturilor precum si pentru electroliti, prognoza performantelor in diferite conditii de functionare si optimizarea depunerii.

Modelul propus consta din doi electrozi, un anod si un catod plus un electrolit corespunzator (figura 1).

Figura 1. Model electrodepunere

Interfata electrod-solutie se descompune in doua parti (figura 2).

Prima parte este un strat compact numit stratul lui Stern, cu o grosime minima in apropierea ionilor din solutie.

A doua parte este cuprinsa intre planul intern a lui Helmholtz (PIH) si planul extern al lui Helmholtz (PEH), confundat cu planul lui Stern.

Din punct de vedere electric, acest strat se comporta ca un al doilea strat condensator de capacitate.


38

Figura 2. Interfata electrod –solutie

Tensiunea de functionare pentru instalatie

este mult mai mica decat cea teoretica reversibila a unui circuit de tensiune deschis.

Acest lucru se datorează diferitelor pierderi de tensiune care apar în cursul aplicării sale.

Principalele tipuri de pierderi sunt: - de activare potential, care este puternic legat

de bariera de activare a reactanţilor ce trebuie trecuta, pentru ca reactia electrochimica să aibă loc; - diferenta de potential, care este cauzată de

rezistentele ionice a electrolitului plus electrozi; - cresterea potentialului si scaderea

concentratiei electrolitului, care apare atunci când electrodul este consumat la interfata electrod-electrolit. De obicei, acesta are drept rezultat un transport mai mic prin intermediul electrodului la interfata electrod-electrolit.

In studiile de analiza pentru modelele 1-D,

2-D si 3-D se tine cont de masa , de impuls si fenomenele de transport de energie sau de o combinatie a acestora. Alte modele iau in considerare fenomenele electrochimice care au loc in timpul functionarii.

Pentru simularea fenomenelor de transport de masa care au loc in timpul functionarii se pot utiliza o serie de modele de referinta dupa cum urmeaza:

- modelul Fick (FM), - modelul Stefan – Maxwell (SMM), - modelul Dusty –Gaz (DGM),

Pentru modelarea se tine cont de trei domenii: - zona anodului (Ωa), - zona specifica electrolitului (Ωm), - zona catodului (Ωc).

Fiecare dintre electrozi are o intrare (∂ Ωa), un colector de curent (∂ Ωa, cc), precum şi un canal de iesire (∂ Ωa, priză).

Zn reacţionează şi se consuma la anod in

stratul activ, pentru transportul ionilor la catod. La catod, Zn reactioneaza împreună cu electronii pentru a forma stratul activ. Zn este transportat prin difuzie şi convecţie.

Legea Darcy se aplica pentru mediul continuu

dintre cei doi electrozi. Pentru distributia potentialului in cele trei

subdomenii se considera urmatoarele trei ecuatii:

,( ) 0ss effk φ∇⋅ − ∇ = pentru anod aΩ

,( ) 0mm effk φ∇⋅ − ∇ = pentru electrolit mΩ ,( ) 0ss effk φ∇⋅ − ∇ =

pentru catod cΩ

Unde:

- Ks, este conductivitatea (S/m) fazei solide; - Km, este conductivitatea (S/m) electrolitului; - φ , potentialul (V) pentru electrod.

Potenţialul (V) pentru electrod este numerotat cu Φs şi pentru electrolit cu Φm . Numărul de atomi depus este proporţional cu numărul de electroni trecut prin circuit.

Putem stabili acest lucru prin măsurarea curentului:

dqIdt

=

0

t

Q I dt It= =∫

Ecuatiile tin cont de presupunerea ca toti electronii sunt folositi pentru convertirea in ioni metalici.

In derularea procesului se tine cont de urmatoarele legi:

- legea de conservare a masei

( ) ,tρ ρ∂ = −∇⋅∂

v

- legea Darcy:

,Pκµ

= − ∇v

- ecuatia chimica de conservare:

( ) ( )eii i i

w D w wt

ρ ρ ρ∂ = ∇⋅ ∇ −∇⋅∂

v,

Modelul matematic evaluaza efectul parametrilor de depunere cu privire la componenta nanocompozitelor electrodepuse.

In faza preliminara s-a considerat nanocompozitul cu matrice metalica aliaj Zn –Fe faza dispersa particule ceramice si polimerice.


39

La acest model s-a considerat ca fluxurile de ioni de Zn(OH)+ si Fe(OH)+ sunt proportionale cu suprafata de depunere.

Sunt luate in considerare si fazele disperse de particule ceramice si polimerice. Depunerea de Zn-Fe se considera neregulata.

2. PARAMETRII MODELULUI

PENTRU DETERMINAREA ECUATIILOR MATEMATICE

In stratul de difuzie particulele sunt transferate

prin difuzie, migratie si convectie. In afara stratului de difuzie, solutia se

presupune ca este bine amestecata iar concetratia este uniforma.

Fluxul se defineste dupa cum urmeaza: i

i i i i i y idcdN z u Fc D v c

dy dyΦ= − − +

Pentru bilantul de material rezulta:

0i iN R∇⋅ + = Apoi devine:

2 2

2 2( )i i ii i i i i

dc d c d cdz u F c D Rdy dy dy dy

Φ+ + +

Indicele „i” este rata reactiei chimice omogene. Domeniul Ω pentru electrolit este delimitat de expresia

A C RΓ = Γ Γ ΓU U .

Figura 3. Frontiere model

Limita este constituita prin izolarea

domeniului, in frontiera anodica AΓ si in cea

catodica CΓ (fig.3).

In domeniul electrolitic Ω potentialul electric este data de ecuatia ce descrie migratia ionica.

Se aleg conditiile la limita astfel: - în ecuaţia electrolitului Ω indicele

<u> este pentru potenţial şi <j> este pentru intensitatea curentului,

- pentru domeniul de granita ΓR se considera valoarea zero ,

- pe graniţa catodica ΓC şi pe graniţa anodica ΓA sunt atribuite puterile de polarizare.

Aceste legi descriu cinetica de reacţie pentru electrozi.

R

C

A

in zona electrolitului

zona superioara

la catod

la anod

( ( )) 0

0

( ( ))

( ( ) )

div gradu xunu f u xn

u g u xn

σ

σ

σ

σ ϕ

− ⋅ = Ω∂ = Γ∂∂ = Γ∂∂− = − Γ∂

Vectorul densitatii este determinat de

gradientul local al potenţialului u (x) în domeniul Ω cea a electrolitului fiind stabilit cu legea lui Ohm.

La fiecare punct X din limita Γ j densitatea de curent (X) este descrisă de ecuaţia.

u

( ) /j gradj x j n u n

σσ

= − ⋅

= ⋅ = − ⋅∂ ∂

r

r r

Comportarea electrochimica a anodului si cea a

catodului prin functiile specifice f si g sunt considerate neliniare, sistemul fiind neliniar.

Problema este rezolvata prin metoda de analiza cu element finit la care se considera tehnica Newton-Raphson.

Pentru suprafata Γ se considera:

* *( ) ( ) ( , ) ( ) ( ) ( , ) x

C x u x j x y u y d j y u x y dΓ Γ

∀ ∈Γ

= − Γ + Γ∫ ∫

C(x)=1/2 pentru x = 1 pentru x

∈Γ∈ Ω

Rezultatele obtinute prin simulare pentru

electrodepunerea analizata sunt strans legate de masuratorile efectuate, rezultatele contribuind la optimizarea configuratiei depunerii.


40

3. CONVECTIA, MIGRAŢIA ŞI DIFUZIA NANOPARTICULELOR

Pentru bilantul de materiale pentru

nanoparticule depuse se considera urmatoarea ecuaţie:

( )c D c zbFc V cu Rt∂ +∇⋅ − ∇ − ∇ + =∂

r

- D este coeficientul de difuzie a nanoparticulelor ; - R este rata de reacţie; - c este concentraţia de nanoparticule; - F este constanta lui Faraday (96485.34 C mol-1); - Z numarul de nanoparticule; - V potential electric aplicat; - B gradul de mobilitate a nanoparticulelor; - ur viteza fluidului.

In cadrul sistemului analizat raza nanoparticulelor este estimata a fi in intervalul de 40nm la 200nm.

In cadrul ecuatiei Nernst-Planck prin adaugarea elementelor de flux rezulta urmatoarea expresie:

( )p pfN D c zbFc V cu gbcν ρ ρ= − ∇ − ∇ + − −r r r

Unde pν este volumul molecular al nanoparticulelor.

Sunt luate in considerare efectul de cuplare ce include interactiunea dintre strat si particule la nivelul interfatei specifice.

Fluxurile convective de migratie si de difuzie a nanoparticulelor poate fi explicata prin ecuatia Nernst-Planck in care aceste fluxurile sunt proportionale cu gradientul concetratiei nanoparticulelor.

Pentru modelarea preliminara s-a considerat: - un model 2D multifizic cuplat cu reactia fizico-

chimica a procesului de depunere; - un model simplicat al stratului depus (figura 4); - in final modelul ajunge intr-o stare de echilibru; - validarea modelului se va face folosind datele

experimentale.

Figura 4. Modele de structura nanocompozite

4. MODELUL MAXWELL-STEFAN PENTRU DIFUZIE ŞI CONVECŢIE

Legea lui Fick se bazează pe presupunerea că fractiunile dizolvate într-o soluţie sau în amonte de lichid interacţionează numai cu solventul sau cu fluidul purtător.

Coeficienţii de difuzie care descriu astfel de interacţiuni sunt independenti de concentratie.

Cu toate acestea, în soluţii concentrate sau amestecuri de fluid, în cazul în care concentraţiile relative sunt de acelaşi ordin de mărime, toate fractiunile interacţionează unele cu altele şi cu ele înseşi.

Coeficenţii de difuzie sunt, prin urmare, fracţiuni de concentraţie, temperatură şi presiune.

In cazul modelului Maxwell-Stefan pentru difuzie şi convecţie modul de aplicare permite modelarea amestecului, prin crearea ecuaţiile multicomponent in cazul transportului de masa.

5. MODELUL AMESTEC

Modelul considerat este un amestec

macroscopic intre doua componente, o faza continua si una dispersa.

Modelul amestec este valabil in cazul cand faza continua este un lichid iar cea dispersa consta din particule solide, picaturi de lichid sau bule.

Modelul amestec se bazeaza pe urmatoarele ipoteze:

• densitatea fiecarei faze este aproximativ constantă; • ambele faze împărtăşesc acelaşi domeniu de presiune; • viteza relativă dintre cele două faze in echilibru este determinata în esenţă, de presiune, gravitatie, şi viscozitate.

6. CONCLUZII

Pentru modelul de analiza matematica preliminar a procedeului de electrodepunere si de realizare a straturilor nanostructurate s-au considerat mai multe submodele combinate în cadrul modelului de baza initial si anume: o submodelul pentru două faze fluide pentru

electrolit respectiv ioni din solutie pentru depunerea nanocompozitelor;

o submodel amestec pentru electrolit si particule in suspensie;

o submodel mediu conductiv corespunzator electrozilor ;

o submodel difuzie si convectie de tip Maxwell-Stefan;


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o sudmodel difuzie in desfasurarea reactiilor electrochimice,

o submodel Nernst-Planck; Proiectarea elementului finit s-a efectuat cu anumite

ipoteze simplificatoare, iar limitările performanţelor lui sunt generate atât de anumite aspecte matematice cât şi experimentale.

Modelarea matematica a permis descrierea fenomenelor electrochimice si a celor de transport masic care apar in difuzarea straturilor si pentru electroliti, prognoza performantelor in diferite conditii de functionare si optimizarea procesului de depunere.

Modelul matematic evalueaza efectul parametrilor de depunere cu privire la componenta nanocompozitelor electrodepuse.

Tipul de depunere si modul de realizare depind de urmatorii parametrii:

compozitia si teperatura electrolitului, concentratie electrolit, tensiune si intensitate curent, pH-ul solutiei, densitate curent, turatie agitator electrolit, caracteristici particule in suspensie, viteza de reactie, concentratia surfactantului.

7. BIBLIOGRAFIE

1. Sohoran, St., Constantinescu I.N. - In the

practice of modeling and finite element analysis, Editura Politehnica Press, Bucharest, 2003;

2. Nanostructures & Nanomaterials – Synthesis, Properties & Applications – Imperial College Press – 2004;

3. Electrolytic processes – University of Toronto – 2007;

4. Femlab – Chemical Engineering 2000.

Quick Info

Improving process stability poses a challenge for instrumentation

In today’s ultra competitive environment, chemical industry manufacturers seeking an edge are examining every aspect of their operations in order to find better ways to meet regulatory requirements, enhance productivity and lower costs. These top-to-bottom efforts involve analysing everything from sensor to boardroom: from plant floor data collection devices and components to manufacturing process sub-systems, plant equipment, measurement and instrumentation, automation and controls, and on up through manufacturing execution and enterprise IT systems.

Within plant floor operations, one device that can often represent significant cost is the sensor, particularly in harsh applications such as chemical and petrochemical processing. Often exposed to or immersed in highly corrosive solutions and subjected to extremely high operating temperatures and other severe conditions, sensors are the critical front line probes that gather and deliver key data.

Sensors support reliable and safe operation, provide regulatory monitoring and validation and ensure quality control, process efficiency and optimisation. And these devices must do so with accuracy, stability and fast response time.

Eastman Chemical Company turned to Foxboro’s Dolphin Series pH sensor line to address these issues at a gas scrubber at the company’s Longview, Texas, manufacturing complex. These new sensors contributed to significant cost savings in maintenance and equipment by reducing cleaning, calibrating, and replacement requirements, as well as manufacturing supply costs (Fig.1).


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Eastman Chemical Company’s Texas operations manufacture more than 60 major chemical and plastic products for sale to customers worldwide. The operation employs over 1800 people to annually produce and ship 3.2billion pounds of product – or 8.8million pounds per day.

Eastman’s gas scrubber uses water and caustic in a 20percent sodium hydroxide solution to remove hydrochloric acid from a flue gas stream before it is vented.

To meet Eastman’s own stringent environmental quality standards and to comply with Federal Resource and Conservation Recovery Act (RECRA) requirements, the company must ensure that the acid gas content in the vented emissions is within acceptable levels. Reliable measurement of the pH level in the caustic solution is critical for effective scrubbing, and meeting the regulatory limits. Beyond environmental quality monitoring and control, minimising caustic chemical consumption costs associated with the waste treatment process also depends on reliable pH measurement.

To monitor the pH levels, the scrubber uses a two-probe redundant system to ensure continuous operation in the event of a single sensor failure. The probes are tied to an automatic shut down system that aborts the scrubbing operation if the pH is outside acceptable limits.

Operational conditions within the scrubber present significant challenges for process pH sensors. These conditions include exposure to the liquid caustic at a nominal operating temperature of 185ºF and pH of up to 10.5.

Due to severe conditions in the scrubber, the old pH sensors had to be replaced frequently – often within two weeks of installation and even as frequently as three times per week. Because the sensors could not withstand the environment, readings were not accurate, which caused operators to have to add caustic, resulting in higher pH values and driving up the use and cost of this manufacturing supply. The higher pH values, in turn, would etch the glass on the sensors, resulting in inaccurate performance and faster rates of failure. The end result of this snowball effect was unacceptably high manufacturing and maintenance costs.

“Frequent sensor failure caused unreliable pH measurements which required additional samples to be analysed by the control room operators,” noted Wyatt Partney, senior control systems technician, Eastman’s Longview facility. “That resulted in increased loads on downstream processes,” he added.

Eastman process improvement engineers working in the scrubber operation and the company’s plant-wide Process Control Group looked at a range of options to upgrade the existing sensors. After determining that the next generation product from the existing sensor supplier was not available, and other options were not adequate for the job, Eastman Chemical tested the new Foxboro Dolphin high temperature pH sensors.

Designed specifically for process industry applications that span the entire pH scale, have strong chemical concentrations and high solids, run at high temperature, and cycle from high-to-low temperature, these sensors were an ideal solution.

The sensor’s novel pH glass formulation provides superior measurement stability and accuracy, and longer service life in high temperature applications of up to 250ºF (121ºC). The pH glass also increases response speed up to five times and provides longer duty cycles, compared to conventional sensors.

The sensor’s new reference electrode construction includes an ion barrier to protect and stabilise the reference potential in harsh conditions. Both electrodes are packaged in a rugged mechanical housing that facilitates installation, removal, cleaning, and calibration, reducing maintenance time and costs.

The results of Eastman’s Dolphin sensors testing were very impressive. The sensors’ patent-pending pH glass formulation increased pH sensor life to six months – a dramatic improvement from the previous products that were operating properly for three to four weeks at best. The significantly longer life also reduced sensor equipment and related maintenance replacement costs eightfold.

“With the Foxboro Dolphin pH sensors, Eastman’s equipment and maintenance costs were eight times lower than with the previous sensors, and the efficiency of our scrubber operation was optimised,“ Partney noted.

The sensors also provide more accurate pH readings, ensuring control operators can use the on-line pH measurements to optimise the efficiency of the scrubber operations. And the sensors have resulted in a 50percent decrease in the amount of caustic used as a result of inaccurate pH level measurement that caused operators to continuously add the sodium hydroxide scrubbing solution.

(source: http://www.engineerlive.com/Chemical-Engineer/Instrumentation/Improving_process_stability_poses_a_challenge_for_instrumentation/19410/)


43

THE STUDY OF ROUGHNESS AND RESISTANCE TO CORROSION OF DENTAL ALLOYS

IN THE ORAL ENVIRONMENT

A.D. Cherciu Ciobotaru, Adina Oana Armencia, Maria Ursache

Faculty of Dental Medicine, „Gr.T.Popa”University of Medicine and Pharmacy, Iaşi, ROMANIA

email: [email protected], email:[email protected]

ABSTRACT: Through its enzymatic process, the oral environment is setting out catabolism chemical products, having unfavourable effects on the used in restoration. Increase Cu and Sn percent increase a corrosion velocity and surface aspect. This decrease with increase Mo and Co percent through passive effect. Increase Fe concentration increase corrosion velocity. Al is very affected in Cu presented. Increase percent Si increase corrosion velocity to galvanic effect. Corrosion implies the presence of an electrolyte around the metal or alloys subjected to corrosion, damaging of the crystaline network of the material being governed by the electrochemical laws of kinetics. KEY WORDS: corrosion, stability ions release, alloys, oral environment.

1. INTRODUCTION Medical alloys used in restorative therapy are

involved in the occurrence of some extensive neighborhood pathology, the material itself being able to intervene, through direct mechanic effects or through its components, sometimes with cytotoxic or allergic effect on the periodontal tissue, but also through the surface appearance which influences the colonization and adhesion of the plaque.

The presence of roughness on the surface of the restorations, near the periodontal tissues, is often decisive for their behavior and frequently rises problems in the etiopathogenic interpretation of some inflammatory reactions that occur in their presence.

Besides the qualities of mechanic resistance, a dental material must also meet a series of properties concerning the stability and resistance to corrosion in the oral environment, because, when the surface of an alloy is introduced into a conductive electrolyte, the first becomes the headquarters of two types of chemical reactions: an oxidation reaction or anodic (in which electrons are produced) and a reduction reaction or cathodic (in which the electrons produced in the anodic reaction consume).

2. THE AIM OF THE STUDY The assessment of some metallic alloys behavior

in oral environment was followed, by evaluating “in vitro” the influence of pH and components with oxidation-reduction and complexing character over the stability of some dental materials with different compositions, as well as their surface profile.

3. MATERIAL AND METHOD

There are 2 groups of dental alloys were studied: • The no. 1 group contains alloys based on

Ag-Pd: Palliag • The no. 2 group contains alloys based on Cr-

Co: Vera PD (V) The fragments of alloys have been realized in the

form of tags, with a medium surface of 2-3 cm2, weighed and sterilized with UV rays, out of which 3 samples have been realized, each with a length and width corresponding to the step that the roughness measurement device has to take (1,5cm/0,5cm).

The processing of the samples has been done sequentially according to the indications of the manufacturing company.


44

PH corrections have been realized with NaHCO3, CH3COONa and HCl, while the correction of the ionic strength has been realized with TISAB buffer (Total Ionic Strength Adjudment Buffer) made of NaCl, CH3COONa and CH3COOH.

As an electrolyte the artificial saliva has been used – synthetic matrix, in pH 2-8 domain, and in the presence of the oxalate and tartrate ions with oxidation-reduction and complexing character, at a ionic strength of 35-45 mmol/L. The fragments of thermostatic alloys at 37ºC have been introduced in sterilized containers along with the synthetic saliva (sterilized by autoclaving, for 30 min, at 1 atm) in a report of weight saliva-alloy: 15/1.

Samples of electrolyte have been collected at intervals of 15 days and the concentration of the allied elements has been determined, through spectrometry of atomic absorption with flame (FAAS type PERKIN ELMER 3300) and potentiometer with EMIS (ion-selective membrane electrode type pH-Ion-Meter-OP-202-RADELKIS).

The measurement of surface parameters supposed the calculation of the average roughness (Ra), before and after adding oxalate and tartrate in saliva, using the device Surtronic 3+ (Taylor-Hobson Ltd. Anglia) for this purpose. 5 intervals have been considered for each Ra calculation, registering 3 tracks for each task, in 3 different locations from the polishing direction (perpendicular, oblique, parallel).

Their average has been taken as a final result for each task in the interpretation of roughness, size, form and also of its slope (profile, height, lift curve).

It was followed: - the evaluation of surface appearance and calculation of roughness - the influence of pH on the stability of the bio-metallic materials, working in an interval of pH = 2; 4; 6.5; 8, in electrolyte artificial saliva. - the influence of pH and components with oxidation-reduction and complexing properties, in a pH interval of 2; 4; 6.5; 8, electrolyte synthetic saliva, at which are added 12,6 mg of oxalic acid / 100 ml and 15,0 mg tartaric acid / 100 ml.

4. RESULTS AND DISCUSSIONS In the artificial saliva, with an identical

composition to the natural saliva, the roughness touches values Ra=0,114 µm, having the lift curve with rounded bearing, which reduces the retention of the testing material surface. (figure 1).

Figure 1. The results of measurements for Palliag: a. the profile of the surface;

b. the parameters of roughness; c. lift curve

a

b

c


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Different from the alloy based on Ag-Pd, the roughness of alloy based on Cr-Co reaches values Ra=0,122 µm, the shape of the profiles improves, but not enough for canceling the retention of the surface, and the lift curve remains with an extremely favorable form concerning the retention. (figure 2).

Figure 2. The results of the measurements for VERA PD:

a. the profile of the surface; b. the parameters of the roughness; c. lift curve in the synthetic saliva

The variation of concentration in time of allying elements at the considered pH values is presented in equilibrium diagram concentration-time. (fig. 3) The development of the dissolution process is conditioned by the heterogeneous character of the alloy. Thus, in case of corrosion of the Palliag, the zinc from its content is dissolving after the chemical reaction between anode (respectively the zinc) and cathode, respectively the more electropositive metal (Cu, Fe), to which it is added the hydrogen clearance. The presence of Pt, Pd, Fe, Ni (metals on which the hydrogen is discharged with low voltage) considerably intensifies the corrosion of Zn and Al at acid pH (as one can well see in the adjacent charts).

Figure 3. The variation of concentration of alloy elements in time in electrolyte artificial saliva

solution at pH =2 -8 (a:PG1; b:Vera PD)

a

b

c

a

b


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The equilibrium diagrams concentration-time at the considered pH values and in the presence of oxalic and tartaric acids are presented in figure no 4.

Figure 4. Variation of concentration of the allied materials (Palliag, VERA PA) in electrolyte synthetic

saliva solution at pH=2-8 The change of the salivary composition determines modifications of the profilometry at the alloy based on Pd-Ag (fig. 5), with roughness values Ra=0,27 µm, slightly higher than the acceptable values of a non-retentive quality of the surfaces.

Figure 5. The results of the measurements for Palliag:

a. the profile of the surface; b. the roughness parameters,

c. the lift curve in synthetic saliva.

a

a

a

b

c


47

The higher values of roughness (Ra=0,239 µm) for the alloy based on Cr-Co (VERA PD) are consistent with the appearance of the lift curve which reduces the qualitative value of the material surface, offering possibilities marked by retention (fig. 6), to which the unfavorable shape. Figure 6. The results of the measurements for VERA PD:

a. the profile of the surface; b. the roughness parameters,

c. the lift curve in synthetic saliva.

The higher values of roughness (Ra=0,239 µm) for the alloy based on Cr-Co (VERA PD) are consistent with the appearance of the lift curve which reduces the qualitative value of the material surface, offering possibilities marked by retention (fig. 6), to which the unfavorable shape of the profile and lift curve also contributes. The development of the dissolution process is conditioned by the heterogeneous character of the alloy. The ionization reaction of the metal is developing with appreciable polarization in case of Fe, Co, Ni. The aluminum is strongly corroded in the presence of Cu because of the latter’s higher values of electro-negativity (Cu=1, 8; Al=1, 5) and its more positive standard potential (Cu = 0,33V; Al = -1,66V). The tin is passive at pH=2-4, and at a pH>8. The nickel is passive at a pH>7 and dissolved at a pH=2-6. The molybdenum is active at pH=2-4. The iron and cobalt are active at a pH=2-4 and passive at a pH >9. All these chemical reactions alter the quality of the alloy surface, with increased surface roughness and ultimately compromising the strength of the restorative material.

DISCUSSIONS

Profilometry enabled the evaluation of the surface of some alloys used in prosthetic restorations, with the obtaining of an overall picture via data collection from several points at its level, and the elaboration of the profile in a specific topography (1, 3). We thus performed the registration of the coordinates and the representation of the measured profile (calculation of the various parameters, calculation and representation of the Abbott-Firestone bearing area curve, measurement of the various portions of the profile).

The difference of the images obtained with regard to the profile, the parameter and the bearing area curve is due to the different structural components and to the modification of the saliva used in the study.

The study showed that a surface with a smaller rugosity is rather difficult to obtain given the elements that form part of the alloys considered in the study (filling particles, with size variations depending on the material) and which, due to the hardness differences, do not become abrasive to the same extent, leading to asperities and surface irregularities. (4,7).

The moment the phenomenon of corrosion comes into play, Ra is influenced by the stages that take place during the process of abrasion; thus, initially, a selective wear occurs in the organic

a

b

c


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matrix, which determines the exposure of the inorganic particles; subsequently, mechanic stress dislocates these particles from the matrix. Electrochemical corrosion involves the presence of an electrolyte around the material or alloy subject to corrosion (6). The metal reacts with the electrolyte with which it comes into contact, forming solvated ions or soluble compounds. The reaction products can be easily soluble, as is the case of the ferric chloride resulted followed the dissolution of Fe in hydrochloric acid. If the electrolyte contains complexing agents (for example: C2O2-4), the ions Fe 2+ form soluble compounds of the type Fe(C2O4)2-2, favoring the passing into solution of the ions Fe 2+. These processes explain the experimental data presented in the above diagrams: advanced corrosion in acid environment (pH 2-4) and average corrosion in alkali environment (pH 8), with corresponding modifications of the values of rugosity. The nobler component exercises a protective action over the other metals, the alloy being stable at corrosion (2). This protective action manifests itself only if the atomic fraction of the nobler component constitutes n/8 of the total number of atoms, where n is a whole number comprised between 1 and 17. The nature of the aggressive solution can influence the salts content via the pH and via the presence of some corrosion enhancers or inhibitors. (3). The reducing agents present in the solution (oxalate, tartrate), reduce the electrode potential, favoring corrosion, while the oxidizing agents led to the increase of the electrode potential, stabilizing the metal. (5,6, 8). The presence of the complexing agents or of the alkali pH favors corrosion, displacing the equilibrium towards the formation of the complex ions, for example: Zn2+ in an alkali environment can be found under the form of Zn(OH)+, Zn(OH)2 – intrinsic solubility, ZN (OH)-3, Zn(OH)2-4 . The most strongly corroded alloys are the ones based on Cr and Co. The increase of the iron percentage determines an augmentation of the corrosion speed. The increase of the silica concentration determines an augmentation of the corrosion speed due to the galvanic effect of Si. The corrosion speed drops with the increase of the percentage of Mo- Co, due to the passivation effect of these metals in the alkali environment. (6, 7, 8). The rise of the concentration of Cu and of that of Sn increases the corrosion speed. In the acid environment, the solder is strongly corroded (Ag, Sn,Cu) (4, 5).

5. CONCLUSIONS The investigation of the rugosity of various restoration materials at the level of the oral cavity is justified by the fact that, in the oral environment, the materials are constantly being subject to a process of degradation, due to the physical – chemical processes, as well as to the masticatory pressures. Both determine the so-called “aging phenomenon” – the alloys modify their color due to corrosion. The alloys based on Cr and Ni are resistant to corrosion, whereas the addition of Sn and Cu in the alloys increases the corrosion speed. The resistance to corrosion augments with the addition of the content of noble metals. In the acid environment, Ag, Cu and Fe speed up this process. The addition of Co and Mo increases the resistance to corrosion in all the investigated solutions. It is rather difficult to simulate the conditions in the oral environment and its influence on the stability of dental alloys. The synergism between the bacterial flora, the pH and the composition makes it difficult to reproduce, in laboratory conditions, some situations similar to those in the oral environment. REFERENCES [1]. Bollen CM, Lambrechts P, Quirynen M. Comparison of surface roughness of oral hard materials to the treshold surface roughness for bacterial plaque retention: a review of the literature. Dent Mater 1997; 13:258-68. [2].Baha F, Douvitsas G, Paximada H.. Finishing and polishing instruments for composite resins. Stomatologia 2003; 60(3):114-123. [4]. Neto H, Cândido M. Analysis of depth of the microporosity in a Ni –Cr system alloy- effects of electrolytic, chemical and sandblasting etching. Journal of oral Rehabilitation, 30: 556-558, 2003 [5]. Kurtz S., Hodgson A. Corrosion characterisation of Co-Cr- Mo with electrochemical techniques in saline and simulated biological solutions. European cells and materials, vol. 3, sppl. 1: 26-27, 2002 [6]. Bundy K., Williams C. Stress- enhanced ion release- the effects of static loading. Biomaterials, vol. 12, 1991 12. [7] Kim, K. and Oh, K. Corrosion properties on dental restorative alloys. In Proceedings of International Conference on Electrochemistry, SAEST, Chennai, 2002. [8]. Dexter S. C. and Maruthamuthu S. Response of passive alloys with n- and p-type passive films to manganese to biofilms. Corrosion, 2001, paper no. 01256, 1–15.


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COLABORĂRI ŞI REŢELE PENTRU DEZVOLTARE

Radu Popescu

Academia Română –INCE-CEIS, Bucureşti, ROMÂNIA, e-mail: [email protected]

REZUMAT În Economia Globală a Cunoaşterii (E.G.C.) divizarea tradiţională între producţia şi utilizarea cunoaşterii nu mai este relevantă, iar provocarea constă în a ne asigura că procesul inovator este unul cooperativ, implicând producătorii (sectorul public până la un nivel înalt ) şi utilizatorii (sectorul privat, extins mult). O astfel de cooperare cere construirea unor relaţii apropiate între comunitatea de cercetare şi cea de afaceri, prin reţele formale şi informale, atât din punct de vedere social cât şi profesional. ABSTRACT In the Global Knowledge Economy the traditional difference between production and the use of knowledge it is not any more important and relevant. The challange consists in the assurance that inovative process is a cooperative one, involving producers (the public sector till a higher level) and consumers (the private sector largly expanded). Such kind of cooperation requests the buildind ofclose relationship between the research comunity and business comunity, as social as professional point of view. CUVINTE CHEIE: reţea, proces inovativ, training, lidership, infrastructură KEYWORDS: network, innovative process, training, leadership, infrastructure

1. INTRODUCERE Dinamismul relaţiilor în E.C. se bazează pe

echilibru, deschidere şi perspectivă focalizată. Firmele de la frontiera Economiei Globale a Cunoaşterii descoperă că, universul cunoaşterii nu este doar o exploarare fără limite, definită prin cunoaştere de dragul cunoaşterii, că această cunoaştere poate să genereze tehnologii noi, deosebit de valoroase sau idei de afaceri prospere. Rezultatul acestor mutaţii este că, acum începe să apară o interacţiune complexă între guvern, industrie şi universităţi (de stat sau private) mânate de nevoia de a crea prosperitate, de a-şi spori competitivitatea până la nivel global şi de a menţine legături optime între cercetare şi comercializare. Politica naţională trebuie să recunoască acestă interacţie şi să o stimuleze. Constatăm că, în România, în ultimii ani, universităţile şi industria au tendinţa să se apropie prin fonduri speciale puse la dispoziţie de Uniunea Europeană.

Remarcăm că, o altă legătură importantă poate să apară prin clusterizarea firmelor care au expertiză complementară, pentru a creşte avantajul lor competitiv în raport cu marile firme, mai ales în context global.

În mod paradoxal, într-o lume în care globalizarea influenţează tot mai mult strategia firmei şi în care graniţele naţionale nu mai sunt privite ca factori limitativi în dezvoltarea companiilor, devine clar că: avantajul competitiv depinde de concentrarea localizată a persoanelor calificate şi de tehnologiile complementare într-un mediu strâns conectat. Politicile naţionale au menirea să încurajeje această clusterizare.


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2. IMPLICAŢIILE ECONOMIEI GLOBALE A CUNOAŞTERII ASUPRA POLITICII ROMÂNEŞTI

Implicaţiile EGC asupra politicii româneşti se manifestă în diferite feluri:

- creşterea rapidă a economiei online; - intensul proces de schimbări structurale; - impactul complex al competiţiei globale

asupra industriei prelucrătoare (dar şi asupra industriei miniere şi agriculturii).

Din punct de vedere social, aceste dezvoltări implică schimbări masive, nu doar în natura muncii, dar şi în modul de dezvoltare al afacerilor şi industriilor comunităţii. Este de aşteptat că politicienii să dea răspunsuri privind: - promovarea unei economii de piaţă funcţionale, prin

programe ce permit economiei să răspundă la presiunile competiţiei globale şi să permită pieţei să se concentreze pe răspunsuri flexibile şi nu pe aderare rigidă la sisteme economice şi culturale perimate;

- să construiască o structură competitivă prin programe care asigură instituţii puternice (din punct de vedere financiar, politic şi social) pentru viitor, cu accent pe dezvoltarea competenţelor umane şi armonia socială;

- să gestioneze procesul de ajustare pentru a maximiza creşterea generală prin programe ce asigură că economia îşi va atinge potenţialul ei maxim;

- să uşureze sarcina ajustării pentru indivizi, familii şi regiuni, prin programe ce compensează aceste dezavantaje prin schimbare şi sprijin pentru a găsi un loc în Noua Economie.

Pentru a sprijini obţinerea acestor răspunsuri este nevoie de generarea, difuzarea şi utilizarea cunoaşterii pentru crearea de bogăţie şi dezvoltarea societăţii. Odată ce se instalează politicile adecvate, sunt necesare anumite acţiuni speciale pentru a le implementa. Considerăm că aceste acţiuni vizează: - întărirea bazei de C-D atât în domeniile de bază

cât şi în cele strategice; - încurajarea domeniilor de cercetare

interdisciplinare (pentru crearea de noi industrii şi transformarea celor tradiţionale);

- încurajarea creşterii activităţii de C-D în industrie printr-un ansamblu de stimulente suplimentare pentru C-D, mai ales pentru I.M.M.-uri;

- promovarea unei calităţi înalte a educaţiei la toate nivelurile, nu doar în domeniul tehnologiei dar şi în cel social, cultural, relevante pentru E.C.;

- menţinerea şi dezvoltarea educaţiei superioare universitare precum şi a unor sisteme de training complex, pentru cercetători;

- încurajarea recalificării şi învăţării de-a lungul întregii vieţi, pentru a face faţă schimbărilor şi nevoilor cerute de noile locuri de muncă;

- întărirea interacţiilor dintre producătorii şi utilizatorii rezultatelor cercetării ;

- întărirea legăturilor internaţionale şi a colaborării în ştiinţă şi tehnologie: a recunoaşte că, mult peste 99% din cunoaştere este generată în afara ţării;

- a oferi elemente de siguranţă pentru indivizii şi grupurile dezavantajate, pentru rapida schimbare şi trecere la economia informaţională;

- încurajarea unor inovaţii substanţiale de către firmele cu orientare globală şi venituri consistente.

Apare clar că sunt necesare eforturi investiţionale masive în domeniul Cunoaşterii pentru a sprijini şi asigura baza unor industrii puternice, competitive la nivel global. Acestea se cer dublate de politici economice şi sociale corect adaptate şi flexibile. Un leadership eficient bazat pe competenţă şi etică, la nivel politic şi economic, este esenţial pentru succesul României în Economia Globală a Cunoaşterii în secolul XXI.

Pretutindeni există o tendinţă spre globalizare, susţinută în mare măsură de reducerea costurilor de transport şi comunicare. Aceste fenomene sunt de fapt un reflex al revoluţiei cunoaşterii.

3. PRINCIPII GENERALE DE ACŢIUNE

În această lume tot mai dinamică şi mai

competitivă, caracterizată de schimbări tehnologice rapide, cu o creştere continuă în Tehnologia Informaţiei şi Comunicaţiior (TIC) se impun unele principii generale de acţiune. 1. A fi deschis ideilor din afară devine un element

de importanţă strategică. Cea mai mare parte a cunoaşterii este dezvoltată în afara graniţelor, chiar şi în ţări mari şi deosebit de avansate.

Creşterea competitivităţii în cadrul unei economii globalizate, cere mai multă deschidere şi colaborare internaţională în domeniul C-D. Tehnologia înglobată în echipamente, bunuri intermediare, bunuri finale şi servicii va fi o componentă tot mai importantă a fluxurilor economice. Din analiza preliminară efectuată, apare clar că România are un drum lung de parcurs în această direcţie.

2. A avea o populaţie educată şi inovativă devine tot mai important şi mai profitabil deoarece abilităţile oamenilor de a pricepe evoluţia în cunoaştere vor fi decisive pentru a utiliza eficient potenţialul oferit de progresul tehnic, economic şi social. Aceasta implică nu doar nevoia în creştere pentru educaţia superioară, dar şi mai important,


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nevoia de a dezvolta sisteme eficace de învăţare pe întreg parcursul vieţii, deoarece va fi o nevoie în creştere de a continua învăţarea la locul de muncă, dar şi acasă.

3. Dezvoltarea unei puternice infrastructuri pentru I.T. va fi decisivă pentru a putea profita de numeroasele posibilităţi oferite de revoluţia cunoaşterii şi de cea informatică. Această dezvoltare presupune investitii nu doar în infrastructura de bază, dar şi în aplicarea T.I.C. la activitatea economică şi socială. Nu e doar o problemă de hardware, este probabil ca provocarea să fie mai ales una de a concepe şi implementa stimulentele economice adecvate şi un sistem pertinent de reglementări, pentru a culege beneficiile schimbării tehnologice rapide din acest sector. Se cere dezvoltarea abilităţilor populaţiei pentru folosirea acestor noi tehnologii, a învăţa să lucreze eficient ca parte a reţelelor locale, naţionale sau globale.

4. Adaptarea la fenomenul globalizării şi creşterea importanţei cunoaşterii, ca factor cheie pentru bunăstare economică şi socială, va implica abilităţi multiple pentru a aduna, evalua şi aplica cunoaşterea disponibilă la nivel global, la oportunităţile în schimbare. Aceasta va impune modernizarea cunoaşterii de la nivel naţional, aflată în instituţii ca : universităţi şi institute de cercetare şi mai ales întărirea legăturilor lor internaţionale pentru a obţine accesul la creaţia de nouă cunoaştere, acolo unde e dezvoltată pentru prima oară. Această creaţie de cunoaştere se cere însă rapid valorificată.

5. Pentru a profita de potenţialul oferit de revoluţia în cunoaştere, va fi necesară o societate mult mai flexibilă şi o economie capabilă să coopereze cu succes cu nevoia constantei schimbări. Aceasta va continua să solicite metode de stimulare economică eficace şi instituţii care promovează şi facilitează constanta realocare a resurselor, de la eficienţa redusă la utilizări mai eficiente.

4. CONCLUZII

Devin tot mai importante politicile

macroeconomice adecvate, competiţia şi politicile de reglementare. Aceasta înseamnă un sistem financiar care poate aloca resursele spre noile oportunităţi mai promiţătoare ( inclusiv capitalul de risc) şi care poate realoca bunurile de la firmele falimentare spre utilizări mai productive.

Apreciem că România mai are mult de lucru în acest sens: - politicile economice nu sunt încă eficace în

realocarea capitalului spre zonele mai productive de utilizare;

- se resimte nevoia unor pieţe mai flexibile pentru forţa de muncă, spre a facilita realocarea forţei de muncă noi;

- se recomandă imperios stimularea firmelor pentru introducerea de noi tehnologii şi a unor structuri organizatorice;

- dezvoltarea unor forme adecvate pentru a facilita realocarea constantă şi trainingul permanent al personalului pentru noi activităţi;

- sprijinirea persoanelor care nu se pot adapta uşor la un mediu tot mai exigent.

Aceste domenii constituie e o mare provocare pentru România şi vor continua să fie astfel, mai ales în privinţa realocărilor pentru creşterea eficienţei firmei şi depăşirea inegalităţilor regionale. Cerinţele prezentate au implicaţii pentru guvernare ca sistem, care resimte nevoia de restructurare constantă şi realocare a resurselor, nevoie în creştere la nivel naţional şi internaţional. Gobalizarea şi tendinţele spre sistemul de inovare globală, intensifică presiunea spre armonizarea demersurilor guvernamentale pentru protecţia proprietăţii intelectuale, politica concurenţei, reglementări privind taxele şi alte politici economice generale, care duc în final la o creştere a nivelului democraţiei, trasparenţei, şi responsabilităţii. Descentralizarea guvernării este facilitată de revoluţia T.I.C.Aceasta va genera noi provocări pentru cooperare la rezolvarea nevoilor locale şi dezvoltarea mediului global. BIBLIOGRAFIE

[1]. Bragg, A., Bragg, M., ”Developing new business ideas”, Prentice Hall London, 2005. [2]. Ciumara, M., “Investiţie şi corupţie în economia de tranziţie a României”, Al cincelea simpozion internaţional “Investiţiile şi relansarea economică.”Bucureşti, 2003. [3]. Charter, M., Tischner U. (contributing editors), “Sustainable Solutions. Developing products and services for the future.”, Greenleaf Publishing Ltd, Sheffield, U.K., 2001. [4]. Collison, Ch., Parcel, G., ”Learning to Fly”, Capstone Ltd., 2004. [5]. Cooper, L., ”Leadership and Management in the 21st Century”, Oxford University Press, 2005. [6]. Coulson-Thomas, C., “The Knowlwdge Entrepreneur”, Kogan Page, London, 2003. [7]. Crăciunoiu, Ş-T. şi colectivul, Enciclopedia Calităţii, Editura O.I.D-I.C.M., Bucureşti, 2005. [8]. Curtin, T., Hyman, D., Husein, N., ”Managing a Crisis”, Polgrave Macmilton, London, 2005. [9]. Druker, P. F. “Managing of the Future”, Butterworth Heinemann, Oxford, 1994. [10]. Edvinson, L., “Corporate longitude. What you need to know to navigate the knowledge economy”. , Pearson Education Ltd , G.B. 2002. [11]. Holbeche, L., ”High Performance Organization”, Elsevier Butterworth-Heinemann, 2005. [12]. Howkins, J., “The Creative Economy. How people make money from ideas”., Allen Lane, The Penguin Press, Middlesex, England, 2001.


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[13]. Iancu, A., (coord.), “Dezvoltarea economică a României”, Editura Academiei Române, Bucureşti, 2003. [14]. Inamori, K., “Oameni şi profit” , O filosofie pentru secolul XXI, Editura Economică, Bucureşti, 1998. [15]. Ioniţă I., Bănacu, C.S., Stoica, M., “Evaluarea organizaţiilor”, Editura Economică, Bucureşti 2004. [16]. Jensen, B., “Simplicity. Transforming your Work and your Company in the New Economy”, Harper-Collins Publishers, G.B., 2002. [17].Nicolescu, O. Plumb, I.,Pricop, M., Vasilescu, I., Verboncu, I.,(coord.), Abordări moderne în managementul şi economia organizaţiei, Vol.1-4, Editura Economică, Bucureşti, 2003. [18]. Nicolescu, O., Nicolescu, L., ”Economia, firma şi managementul bazate pe cunoştiinţe”, Editura Economică, Bucureşti, 2005. [19]. Ohmae, K., “The Invisible Continent. Four Strategic Imperatives of the New Economy”, Nicolas Brealey Publishing, London, 2001.

[20]. Piţurescu, I., ”Centre incubatoare de afaceri”, Editura Giuleştino, Bucureşti, 2002. [21]. Popescu, R., “Controlul poluării mediului în întreprinderile industriale”, Canada, British Columbia, University of Victoria, Proceedings, 1996. [22]. Popescu, R., Stoica, M.,“Provocări ale Managementului în secolul XXI”, Germania, Bochum, Proceedings, 2004. [23]. Stoica, M., Doval, E., Popescu, R. , Ivănel, D., Jors, C. ”Evaluarea riscului financiar- bancar”, Editura TIPART, Bucureşti, 2004. [24]. Stoica, M., Ioniţă, I., Botezatu, M., “Modelarea şi simularea proceselor economice”, Editura Economică, Bucureşti, 1997. [25]. Teece, D.J. , ”Managing Intellectual Capital”, Oxford University Press, 2002. [26]. Vasilescu, I. Românu, I., “Dicţionar de investiţii”, Editura Lumina Lex, Bucureşti, 2003. [27]. Vasilescu, I., ”Pregătirea, Evaluarea şi Auditul Proiectelor”, EfiCon Press, Bucureşti, 2006.

Quick Info Process Engineer - Plant Management. Opensafety protocol cleared for international standardisation

Opensafety, the fieldbus-independent protocol, has been tested according to IEC 61784-3 FSCP 13 and approved by national IEC committees representing 27 countries including China, the USA and Germany. Opensafety has therefore been released for international standardisation. Because Opensafety is bus-independent, it is said to be suitable for use with all fieldbus or industrial Ethernet systems. At the HMI 2010 trade fair, Opensafety was presented in applications using some of the most popular industrial Ethernet protocols: Sercos III, Modbus TCP, Ethernet/IP and Powerlink. For the first time, users of an industrial Ethernet system other than Powerlink now also have a complete, certified and open safety system available to them. Opensafety has been certified by TÜV Rheinland and TÜV Süd for SIL 3 applications. Stefan Schoenegger, the open automation business unit manager at B&R, comments: "End customers have been requesting a uniform and manufacturer-independent standard for years, and Opensafety is the response to those requests. It allows increases in productivity that are currently not possible with other safety protocols." For more information, visit www.open-safety.org (source: http://www.engineerlive.com/Process-Engineer/Plant_Management/Opensafety_protocol_cleared_for_international_standardisation/22975/)


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STRATEGIA MICILOR ÎNTREPRINDERI ROMÂNEŞTI ŞI INOVAŢIA, CA FACTOR DE SUCCES

PE PIAŢA EUROPEANĂ

Adina Gabriela Dascălu

University of Craiova, Craiova, ROMANIA, e-mail: [email protected]

REZUMAT Inovaţia este un proces a cărui finalizare este o realizare originală şi creatoare de valori. Ea dă invenţiei dimensiunea sa economică. Firmele orientate spre inovaţie au şanse mai mari de câştig faţă de concurenţi, fie prin reducerea preţurilor ca urmare a reducerii costurilor, fie prin realizarea unor produse mai performante care aduc o mai mare valoare clienţilor. Pentru o mare companie europeană inovaţia poate fi foarte la îndemână având în vedere fondurile de care dispune, spre deosebire de micile întreprinderi, care pot fi foarte inovative, dar întâmpină mai des dificultăţi de finanţare. Totuşi, există mai multe tipuri de strategii mai puţin costisitoare la care acestea pot recurge, care îmbinate cu o corectă stabilire a priorităţilor pot crea o poziţie solidă pentru o întreprindere de talie mică, pe piaţa europeană. ABSTRACT Innovation is a process whose objective is the achievement of a valuable, original and creative outcome. It gives the invention its economic dimension. Innovation-oriented firms are more likely to win over competitors, either by price reduction by following the reduction of costs, or by making better products that bring greater value to customers. For a leading European company innovation can be very handy having regard to available funds, unlike small businesses, which can be very innovative, but often encounter financing difficulties. However, there are several less expensive types of strategies the former can use, which merged with a correct prioritization can create a strong position on the European market, even for a small firm. CUVINTE CHEIE: strategii ale inovaţiei, prioritizarea, diferenţierea produsului, ameliorarea performanţei producţiei, funcţia de cercetare-dezvoltare KEYWORDS: inovation strategies, prioritization, product diferentiation, production performance improvement, the research and development function

1. INTRODUCERE

În funcţie de formă şi intensitate, se poate stabili o tipologie a strategiilor inovaţiei. Primele elemente avute în vedere sunt produsele şi pieţele, de la pieţe şi produse existente, la pieţe şi produse noi, care implică riscuri de fabricaţie şi tehnologice.

O firmă nouă are avantajul de a se îndrepta spre inovaţie, mai ales dacă se combină cu crearea noilor pieţe sau produse [1], în acest caz nefiind obligată să înfrunte concurenţa şi competitivitatea firmelor existente.

Dacă se consideră drept criterii pentru stabilirea zonelor de risc a firmelor, zonele de pieţe abordate, neabordate şi noi, pieţele cu risc redus şi mediu se situează în zona microinovaţiilor, cu o

rată a eşecului de 30%, faţă de 80% în zona macroinovaţiilor. 2. TIPOLOGIA STRATEGIILOR

INOVAŢIEI

Pentru alegerea celor mai bune mijloace de a concura pe piaţa europeană, micile întreprinderi româneşti trebuie să aibă în vedere mai multe aspecte ale strategiilor care pot deveni factori de succes sau de eşec dacă nu sunt cunoscute şi luate în considerare.

O primă concluzie este următoarea: cel mai bun mod de a reuşi este inovarea în domeniul de activitate în care firma este deja prezentă.


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A doua concluzie este că e mult mai puţin riscant ca firma să lanseze produsul pe o piaţă care există decât pe una care trebuie creată. Această strategie este inaccesibilă firmelor mici deoarece necesită mijloace de finanţare însemnate şi foarte repede alocate.

O a treia concluzie este că un produs nou de succes este superior celor existente din punctul de vedere al performanţei sau are un preţ inferior la performanţă egală. Strategia întreprinderilor noi inovatoare presupune evitarea inovării în marketing, adică diferenţierea produsului nou pe baza unui element funcţional. Poziţionarea este o practică dificilă şi este accesibilă numai marilor firme, care au un marketing riguros. Diferenţierea prin imagine este o practică care trebuie rezervată numai produselor sau mărcilor deja lansate pe piaţă.

Cea de-a patra concluzie este că reuşita unui produs nou sau ameliorat trece mai întâi prin inovaţia tehnică. Transferul de tehnologie este o a doua metodă de succes. Reuşita este totală dacă se asociază un marketing corespunzător, ceea ce conduce la următoarele observaţii:

• erorile de marketing sau absenţa acestuia pot conduce la eşuarea unei inovaţii tehnice;

• rareori un produs nou care nu a fost realizat pe baza inovaţiei reuşeşte numai datorită eforturilor de marketing.

În sectorul produselor finite, logica dezvoltării economice elimină puţin câte puţin firmele de mici dimensiuni, ce deţin activităţi de producţie şi desfacere ale produselor de larg consum. Ele pătrund tot mai mult pe pieţe mai restrânse, specializându-se pe realizarea bunurilor ce interesează o categorie redusă de utilizatori. Prin urmare, strategia tip a micilor firme inovatoare româneşti poate consta în câştigarea unei poziţii solide pe o piaţă restrânsă, datorită diferenţierii produselor lor, ce rezultă dintr-un avans tehnic asupra procedeelor de fabricaţie; dacă ele înfruntă concurenţa firmelor mari, precum numeroasele firme europene, vor avea de câştigat din atuurile lor specifice: flexibilitatea şi viteza de reacţie. Aşadar, caracteristicile mediului firmei condiţionează structurile acesteia: cu cât mediul este mai nesigur, cu atât mai diferenţiate trebuie să fie structurile.

Diferenţierea constă în valorificarea mai ales a statutului cercetării-dezvoltării, dacă:

• domeniul de activitate este, din punct de vedere ştiinţific şi tehnic, în dezvoltare puternică;

• factorii discriminanţi ai alegerii clienţilor sunt de esenţă tehnică.

Ierarhizarea preferinţei între marketing şi cercetare – dezvoltare trebuie făcut în beneficiul funcţiei care deţine cea mai mare putere de reducere a incertitudinii. Dar nu este suficient: cu cât este mai ofensiv comportamentul firmei pe plan tehnic, cu atât este mai mare succesul politicii sale de

integrare precoce a acestui binom. În firmele româneşti, funcţia de cercetare-dezvoltare există numai de o manieră informală şi difuză – de aceea se şi situează pe locul doi, după producţie. Astfel, numeroase avantaje economice induse de inovaţii tehnologice sunt rapid pierdute.

3. PRIORITĂŢI ÎN OBŢINEREA

PERFORMANŢEI

Situaţia de impas concurenţial al firmelor româneşti se concretizează prin rare surse de diferenţiere şi un slab potenţial al avantajelor, ceea ce face ca firmele să se înfrunte numai prin preţuri. Până acum, firmele româneşti şi-au elaborat strategia bazându-se pe o sumară analiză financiară.

O strategie de producţie nu trebuie să asigure eficienţa maximă sau perfecţiunea tehnică, ci coerenţa deciziilor structurale, adică fundamentarea capacităţii de producţie, tipul şi localizarea instalaţiilor, alegerea tehnologiei de proces sau limitele integrării verticale. La acestea se adaugă deciziile tactice, adică natura efectelor, gestiunea calităţii, fluxul materialelor şi organizarea producţiei şi a muncii.

În opinia mea, priorităţile pentru firmele româneşti pentru următorii ani ar putea şi rezumate astfel:

• capacitatea de a asigura oferta la preţuri competitive;

• capacitatea de a face schimbări rapide de concepţie;

• capacitatea de a face schimbări rapide de volum;

• capacitatea de a oferi produse foarte performante;

• capacitatea de a efectua livrări rapide şi sigure;

• capacitatea de a asigura servicii post-vânzare.

Orientările strategice ale firmelor româneşti pe viitor trebuie să fie:

• creşterea părţii de piaţă pe pieţele existente;

• intrarea pe noi pieţe cu produsele existente;

• cesiunea unor activităţi; • dezvoltarea noilor produse pe pieţele

existente; • dezvoltarea noilor produse pe noi pieţe; • integrarea orizontală, în amonte sau în

aval, în limitele prevăzute de politicile concurenţiale.

Dacă se efectuează o analiză strategică a firmelor româneşti prin prisma priorităţilor şi orientărilor strategice prezentate mai sus, se poate constata că stereotipurile încă persistă în gândirea economică şi strategică. Stereotipul pune accentul pe pieţele existente.


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Firmele româneşti nu sunt orientate spre integrare, calitatea trebuie să devină o prioritate pentru acestea, serviciile pot-vânzare şi flexibilitatea fiind neglijate încă de multe dintre ele, majoritatea preferând lupta cu produse ieftine, dar de o calitate acceptabilă sau bună.

Pe baza celor prezentate, se pot identifica următoarele direcţii strategice de urmat:

• Concentrarea pe procesul de producţie, urmărind ameliorarea performanţei producţiei pe termen lung. Managerii trebuie să înţeleagă că ameliorarea performanţei productive are o importanţă capitală pentru succesul firmei pe piaţa europeană. În acest scop ei trebuie să îşi impună autoritatea, să fixeze obiective ambiţioase, ceea ce impune o acţiune pe termen lung, favorizând flexibilitatea pe termen scurt, minimizând astfel timpul necesar schimbării.

• Adoptarea distribuţiei pe piaţă a produselor de primă calitate, în timpul dorit şi la preţuri competitive, acesta fiind un obiectiv explicit al procesului de producţie.

• Tehnicile noi trebuie să încurajeze inginerii şi managerii să încorporeze în concepţia iniţială a produselor calitatea procedeului de fabricaţie. Un efort de ameliorare continuă, atât în faza de prototip, cât şi în faza de producţie, contribuie la introducerea rapidă pe piaţă a produselor, ceea ce reduce la minimum revizuirea proiectelor şi a termenelor.

• Supravegherea acţiunilor pentru care salariatul se angajează mai mult, se specializează mai puţin şi este dispus să înveţe permanent.

4. CONCLUZII

Aşadar, aplicarea strategiilor tradiţionale şi

orientarea firmei româneşti spre direcţiile prezentate anterior, îi pot oferi acesteia armele pentru a face faţă ameninţărilor venite din partea rivalilor străini.

Totuşi, există şi alte metode şi strategii de obţinere a unor bune performanţe, chiar evitând o luptă costisitoare cu firme mai experimentate, mai puternice sau care dispun de resurse abundente. Referinţe [1].Ion Ciobanu, Ruxandra Ciulu - „Strategiile competitive ale firmei”, Editura Polirom, 2005, Iaşi.

Quick Info

Safety culture key to preventing tank farm disasters in the future

Didier Turcinovic argues that awareness and responsibility are needed to establish the sort of safety culture which will prevent future tank farm accidents.

The major fire that erupted at the Buncefield tank farm in Hertfordshire, England, was caused by the ignition of a vapour cloud. The fire started at 6 am on 11th December 2005 and lasted for three days. On that day, the site was holding around 35 million litres of petrol, diesel and aviation fuels.

In the surrounding areas, a total of 80 businesses employing about 4000 people were destroyed or badly damaged. The only good news is that the timing of this accident was in the favour of the employees and surrounding areas, so there were no fatalities. Had this incident occurred during normal business hours, Buncefield could have been the most deadly European industrial accident ever.

On 23rd March of the same year, across the Atlantic, a BP refinery in Texas City also experienced the ignition of a vapour cloud. This accident resulted in 15 fatalities and over 170 injuries.

Again, it could have been a lot worse if you consider that the company employed about 1800 full-time and part-time employees, as well as additional contract workers, with traffic ranging from 1000-5000 people on site per day during peak activity. The Texas City plant is BP's largest refinery worldwide and the third-largest in the US, producing about 2.5 per cent of the gasoline sold in that country.

These accidents are just the tip of the iceberg. Located in populated Western world regions, they produced dramatic images, feeding extensive media coverage. Awareness

Such events stimulated awareness around the world from the politicians to the general public, through to professional experts and industrialists. In order to get a broader understanding of the consequences, it helps to consider workplace accident information. This information is not readily available outside the accidentology and labour specialists circle because databases are set up to meet specific needs and scopes, and it is almost impossible to compare like to like. However, one can access varied and meaningful indicators.

The major accident reporting system (MARS) database(1) records show that approximately 30 major accidents happen each year within the industry sectors covered by the Seveso II directive in the EU. By definition these accidents


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have or potentially have major consequences for individuals and the environment.

Workplace accidents and disease costs are increasing and estimated to be about 3 per cent of gross national product (GNP) for most countries in Europe and around 4 per cent worldwide(2). Annual estimates of global work-related deaths amount to 1.1 million(2).

Major accidents in the process industries worldwide have not shown significant improvement over time when the sole damage cost of these accidents is considered. In fact, from the mid 1960s to the late 1990s they more than doubled (using a linear trend model). From 2000 to 2005, there are still no measurable signs of improvement(3). Human factors

These figures leave no doubt that we face a serious matter. An Analyse, Recherche et Information sur les Accidents (ARIA) study(4) reports that the root causes of over 50 per cent of the accidents in France are human and organisational factors. When analysis extends beyond the immediate causes, people and management are involved in almost all cases. Another source(5) indicates that the root cause of 40 per cent of accidents is due to inadequate specifications.

In practical terms, what does this mean for us in engineering offices and on plant sites? It means, at a minimum, a thorough implementation of process safety management, risk management programmes and functional safety standards and rules. It means not just producing paperwork, but performing detailed and valid assessments, verifications, inspections and investigations.

The BMIIB report(6), The Baker Report(7) and the Testimony of CW Merritt before the US Senate Committee(8), state a number of observations or recommendations. All refer to specific industry standards and rules, and their timely and thorough implementation. They also point out the need for the development of what we could call a 'positive safety culture'.

In practical terms, what does this mean for us, the citizens? This question might sound odd, but you may feel the burden of the social cost(2) and the psychological impact(9) of incidents; you could be a victim, or know someone who was; you may fear plant relocation forced by the perceived unsafe activities of plants; your children may contribute to the 'brain drain' by not studying engineering or chemistry because they don't see employment in a plant as a desirable or secure job; or perhaps you paid too much to fill up your car with petrol this year?

If any of these points ring true, then you can confidently say that you are not living in a society with a positive safety culture. We all need to take responsibility. The first step is awareness. The second step is to invest in building

a proper safety culture. The question is: how much profit needs to be made before industrialists take the leadership of a positive safety culture?

Didier Turcinovic is a TÜV Functional Safety Expert and president of Safety Users Group, San Jose, CA, USA. www.safetyusersgroup.com. Safety Users Group is an independent professional community supporting the advancement of positive safety culture worldwide through the exchange of knowledge and experience in functional safety and standards such as IEC 61511, IEC 61508, ISA 84.

REFERENCES: 1 Major Accident Reporting System. European Commission, Joint Research centre, Ispra. http//:mahbsrv.jrc.it; 2 Accident and diseases information, International Labor Organization. http://www.ilo.org; 3 Source DNV Consulting, ARIA data base; 4 ARIA report on technology accidents 1992 - 2005; 5 Out of Control. Why control systems go wrong and how to prevent failure. Published by HSE. ISBN 0717621928; 6 BMIIB, Buncefield Major Incident Investigation Board - Recommendation on the design and operation of fuel storage sites. www.buncefieldinvestigation.gov.uk; 7 Report of the BP U.S. refineries independent safety review panel; 8 Testimony of Carolyn W. Merritt, Chairman and CEO US Chemical Safety Board before the US Senate Committee on Environment and Public Works Subcommittee on Transportation Safety, Infrastructure Security, and Water Quality July 10, 2007. http://www.csb.gov/news_releases/docs/MerrittSenateEPW7-10-07Written.pdf ; 9 Chemical plants are perceived as a higher risk than nuclear plants by the public in France with a growing perception, +10% between 2001 and 2004. See IRSN survey, Préventique magazine N°82, July-August 2005. (source: http://www.engineerlive.com/Process-Engineer/Safety_in_the_Plant/Safety_culture_key_to_preventing_tank_farm_disasters_in_the_future/22146/)


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CERCETAREA IN ROMANIA – TRENDURI ACTUALE

Nicoleta Gudanescu

Universitatea Nicolae Titulescu, Bucuresti, ROMANIA, e-mail: [email protected]

REZUMAT Lucrarea de fata prezinta Sistemul National de Inovare, precum şi strategiile naţionale şi regionale ale inovării. De asemenea, este prezentata corelatia dintre antreprenoriat şi inovare si contributia cercetarii si inovarii la dezvoltarea IMM-urilor din tara noastra. Lucrarea ofera informaţii cu privire la Sistemul Naţional de Cercetare şi Dezvoltare, Infrastructura de Inovare si de Afaceri, indicatori specifici ai Strategiilor Regionale de Inovare si posibile orientari pentru viitoarele acţiuni politice care sa contribuie la dezvoltarea acestui sector in Romania. ABSTRACT The paper work presents the status of Romanian National Innovation System and National and Regional Innovation Strategies. The innovation based entrepreneurship and innovation indicators in Romanian SMEs are high-lighted, also. The paper work provides in the mean time information about National Research and Development System, Innovation and Business Infrastructure, specific indicators of Regional Innovation Strategies, and possible orientation for future policy actions. CUVINTE CHEIE: cercetare, inovare, antreprenoriat, clustere de firme, poli de dezvoltare regionala KEYWORDS: research, innovation, entrepreneurship, custers, regional development poles

1. INTRODUCERE

Inovarea este driverul schimbărilor sociale şi economice, şi are rolul de motor pentru consolidarea pozitiei tarii noastre si contributia la competitivitatea europeană.

In prezent, inovarea este luată în considerare în strategia de afaceri şi programele politice de catre toate ţările europene. Evoluţia procesului de inovare este lenta, în multe dintre tarile europene, după cum arata raportul European privind inovarea tehnologică (European Innovation Scoreboard, 2008).

În acest context, necesitatea de a difuza, sensibiliza opinia publica şi de formare în materie de inovare, intervin la toate nivelurile economice si sociale si sunt inerente procesului de dezvoltare şi de creştere a competitivităţii întreprinderilor.

2. SISTEMUL NATIONAL DE INOVARE DIN ROMANIA În economia bazată pe cunoaştere, inovarea, joaca un rol central, dar până de curând procesele complexe de inovare au fost insuficient înţelese. Noutatea este factor dominant de creştere economică la nivel naţional şi internaţional dar si in cadrul schimburilor comerciale.

La nivel microeconomic pentru firme, cercetarea - dezvoltarea (CD & I) poate fi vazuta drept capacitatea de absorbţie de cunoştinţe noi de toate tipurile, nu doar a cunoştinţelor tehnologice (Manualul OSLO) Un sistem naţional de inovare a fost definit după cum urmează: - ".. o reţea de instituţii din sectorul public şi

privat, ale căror activităţi şi interacţiuni constau in difuzarea noilor tehnologii. "(Freeman, 1987)

- " .. acel sistem de instituţii distincte, care, împreună şi individual contribuie la dezvoltarea şi difuzarea de noi tehnologii şi care oferă cadrul în care guvernele pun în aplicare


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politicile ce sustin procesele de inovare. Ca atare, este un sistem de instituţii interconectate pentru a crea, stoca şi transfera cunoştinţe, aptitudini şi rezultate care definesc noile tehnologii. "(Metcalfe, 1995)

Modalitatile de a promova inovarea şi antreprenoriatul în perioada 2007-2013, sunt: înfiinţarea unui fond de capital de risc, dezvoltarea de servicii de incubare, de inovare şi de reducere a barierelor pentru înfiinţarea de spin-off-uri. Centrele incubatoare vor trebui să-şi diversifice serviciile de asistenţă şi sa faca schimb de bune practici cu centrele de transfer tehnologic. Pentru a crea spin-off-uri, principalul obiectiv va fi elaborarea unui cadru juridic favorabil, care să menţină statutul de universitar şi cercetător al celor implicaţi în astfel de proiecte, si sa contribuie la reducerea riscurilor in cazul unor astfel de iniţiative. Inovarea este o componentă importantă a cooperării între companii şi între companii şi entităţi de cercetare-dezvoltare. Prin urmare, reţelele inovative, participarea la platformele tehnologice europene şi dezvoltarea de platforme tehnologice naţionale în domenii strategice vor fi încurajate. Investiţiile în infrastructura de inovare vor fi directionate in domeniile competitive. Cu toate acestea, pentru înfiinţarea de parcuri ştiinţifice şi tehnologice, în special a celor care beneficiază de sprijinul unor mari companii sau universităţi este inca un proces la inceput de drum mai ales in tara noastra.

In aceste conditii principalele instrumente de sprijinire a inovării şi a spiritului antreprenorial sunt: - Infiintarea de parcuri stiintifice si tehnologice - Crearea de spin-offs - Imbunatatirea cadrului juridic - Crearea de retele de inovare - Participarea la platformele tehnologice europene Universitatile, institutele de cercetare-dezvoltare publice si alte entităţi implicate în cercetare, joacă un rol important pentru obţinerea excelenţei in domeniul inovarii. Aceştia sunt invitaţi să se transforme în actori importanţi pe piaţa cunoaşterii, atrăgând şi resursele umane şi concentrand grupari substanţiale de echipamente de cercetare. Implicarea în cercetare şi conexiunile mai strânse cu mediul economic au generat nu doar venituri suplimentare, dar sunt in acelasi timp elemente ale procesului de educaţie şi de formare. Sistemul românesc de CDI a venit dupa o perioadă foarte dificilă de inainte de 1989: investitiile foarte mici si procesul intzârziat de restructurare au fost doar unele dintre dificultatile ce au impiedicat conexiunea la evoluţiile globale în domeniul ştiinţei şi tehnologiei din România iar sectorul industrial nu a putut exercita o cerere reală de inovare.

Practic izolat, sistemul de CD&I a fost fragmentat, diversele componente încercand să supravieţuiască cu minimul de resurse disponibile, în principal prin finanţare publică. ANCS reprezintă autoritatea publică, care supraveghează şi controlează domeniul cercertarii si inovarii in Romania, obiectul său de activitate fiind aplicarea corecta a normelor in domeniu. De asemenea, Autoritatea are rolul de a elabora şi actualiza politicile şi strategiilor din domeniile cercetarii, dezvoltarii şi inovarii. ANCS pune în aplicare strategia de CD &I, prin coordonarea programelor realizate prin intermediul proiectelor. Proiectele sunt realizate de organizaţii naţionale, direct sau prin participarea activă la programe internaţionale. În conformitate cu legislaţia actuală, entităţile care desfăşoară activităţi de cercetare-dezvoltare sunt incluse în Sistemul Naţional de Cercetare-Dezvoltare, care este format din institutii publice şi entităţi private care au activitatile de cercetare şi dezvoltare în statut. In cadrul acestui sistem, o entitate distinctă este sistemul de cercetare-dezvoltare de interes naţional, care include următoarele categorii de entităţi publice, acreditate în conformitate cu Ordonanţa de Guvern 57/2002: - institute naţionale de cercetare-dezvoltare; - institute de cercetare ale Academiei Romane; - universităţile acreditate sau departamentele lor de

profil; - institutele sau centrele de cercetare-dezvoltare

organizate în cadrul societăţilor naţionale, companiilor naţionale sau Regiilor autonome de interes naţional.

1. PROFILUL ORGANIZATORIC AL SISTEMULUI NATIONAL DE CDI

- Total:> 600 (2002 / majoritar de stat: 2 / 3;

majoritar privat: 1 / 3) - Institute Tehnologice de cercetare (institute de

cercetare şi dezvoltare tehnologică):> 200(sectoriale / ramuri industriale profile si 38 Institute Nationale de cercetare şi dezvoltare tehnologică)

- Universitati - 56 universităţile publice si 18 universităţi private acreditate

- Academia Romana - 65 de institute pentru cercetare de bază şi avansata in domenii socio-umaniste şi domenii tehnice

- Academia de Ştiinţe Agricole şi Forestiere - 25 institute şi centre de cercetare, 91 de staţii de cercetare şi de producţie

- Academia de Ştiinţe Medicale - 23 centre de cercetare şi institute, 12 centre medicale afiliate universităţilor


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- Companiile care dezvolta activităţi de cercetare-dezvoltare - 250, în sectoarele public şi privat, inclusiv cele particulare, organizaţii non-profit

4. INSTRUMENTE DE FINANŢARE Principalele instrumente de finanţare sunt subvenţii prevăzute prin ANCS pentru CDI desfasurate prin următoarele programe: - 2007-2013 Planul Naţional de CDI - Programul Cercetare de Excelenta – CEEX - Programul sectorial de cercetare-dezvoltare - Programul INFRATECH; - Programul IMPACT - granturi pentru cercetare ştiinţifică finantate de

acelasi ANCS Cheltuielile publice destinate cercetarii si inovarii au evoluat intre 2000 si 2010, conform graficului de mai jos:

Grafic nr. 1: Cheltuielile publice pentru CDI in perioada 2000-2010

5. RETEAUA NAŢIONALA DE INOVARE ŞI TRANSFER TEHNOLOGIC (RENITT)

Cuprinde 42 entităţi (12 de centre de transfer tehnologic, 15 puncte de informare şi 15 incubatoare de afaceri), precum şi parcuri de Ştiinţă şi Tehnologie (S & T), cunoscute sub denumirea de Parcuri tehnologice în diferite regiuni ale ţării (ANCS, decembrie 2007). RENITT cuprinde toate regiunile de dezvoltare la nivel naţional, cu importante noduri în capitală şi alte mari orase ale tarii. De exemplu Centrul Incubator Tehnologic si de Afaceri -CITAf este primul incubator din România, fondat în 1992 in cadrul Institutului de Cercetare pentru Inginerie Mecanica (ICTCM), cu sprijinul Ministerului Educatiei si Cercetarii. A fost acreditat ca centru de inovare şi transfer tehnologic de catre ANCS in anul 2006.

În comparaţie cu incubatoarele de afaceri, care găzduiesc activităţi economice diverse in general de natură comercială, Parcurile tehnologice si de cercetare, se concentreaza mai mult pe transferul de tehnologie şi consolidarea parteneriatelor între institutele de cercetare, agenţi economici şi universităţi. România are în prezent patru Parcuri S & T situate in Bucuresti, Timisoara, Iasi si Galati. Acestea au fost infiintate in 2007 prin ANCS in cadrul Programului Naţional pentru Transfer Tehnologic şi Inovare INFRATECH, care a oferit sprijin pentru dotarea (500 000 EUR pentru Parcuri din Timisoara, Iasi si Bucuresti). Deşi relativ mici, aceste sume au fost considerabil mai mari decât fondurile alocate pentru astfel de structuri în trecut. Posiblitatile de finanţare pentru activităţi de cercetare au crescut si prin intermediul Planului Naţional de Cercetare, dezvoltare şi inovare (CDI) 2007-2013.Planul este de aşteptat să stimuleze a numărului de proiecte şi parteneriate de cercetare întreprinse în cadrul parcurilor S & T, şi primele semne de ameliorare sunt de aşteptat în următorii doi, trei ani (Market Watch, 2008).

Figura 1. Structura RENITT 6. STRATEGII REGIONALE

DE INOVARE

România are 8 regiuni de dezvoltare create în conformitate cu dispoziţiile din Regulamentul CE nr. 1059/2003 privind stabilirea unei clasificari statistice comune a unităţilor administrativ - teritoriale: - Regiunea 1: Nord – Est - Regiunea 2: Sud – Est - Regiunea 3: Sud - Regiunea 4: Sud – Vest - Regiunea 5: Vest - Regiunea 6: Nord – Vest - Regiunea 7: Centru - Regiunea 8: Bucuresti – Ilfov

RENITT

PARCURI STIINTIFI

CE

INCUBA TOARE

CENTRE DE TRANSFER

TEHNOLOGIC

CENTRE DE INFORMARE


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Strategiile Regionale de inovare sunt elaborate in cadrul agenţiilor de dezvoltare regională: Sud-Muntenia, Nord-Vest, Nord-Est, Sud-Est şi Bucureşti-Ilfov. Proiectele sunt finanţate de Comisia Europeană prin FP 6, FP 7 împreună cu alte proiecte ale tarilor Europene.

Figura 2. Regiunile de dezvoltare - Romania

Cel mai important centru pentru Cercetare si Inovare ca si regiune de dezvoltare este Bucureşti-Ilfov. Din totalul de firme (5171) cu activitate de cercetare inovare din tara noastra in 2007, 1176 (22,74%) se află în regiunea Bucureşti-Ilfov, care au realizat 44.75% din cheltuielile naţionale de inovare la nivel de întreprinderi inovatoare şi de 61.13% din cheltuielile naţionale de cercetare-dezvoltare. Tabel 1. Cheltuielile de CDI pe regiuni de dezvoltare

in Romania (2001-2006) - % Total

cheltuieli CDI

2001 2002 2003 2004 2005 2006

Total 100.00 100.00 100.00 100.00 100.00 100.00

1. NE 5.83 5.06 4.92 5.29 5.52 6.86

2. SE 6.15 4.59 3.47 3.19 3.59 3.46 3. Sud -

Muntenia 14.09 15.82 13.92 14.11 11.34 9.30

4. Sud – Vest Oltenia 4.84 3.76 2.80 5.66 3.80 3.44

5. Vest 3.79 4.63 6.11 4.78 4.46 4.43 6. NV 4.16 6.74 4.80 3.41 7.52 7.45

7. Centru 6.05 6.70 6.66 4.86 4.49 3.89 8.

Bucuresti - Ilfov

55.09 52.70 57.33 58.70 59.29 61.13

Sursa: Date Statistice din Strategia Regionala de Inovare 2001-2007

Mai mult decât atât, Regiunea Bucuresti-Ilfov concentrează aproximativ jumătate din personalul angajat in unităţi de cercetare şi dezvoltare, din totalul de 21,937 angajaţi in acest domeniu la nivel national (51,96% din totalul naţional) şi 14,888 cercetători (49,42% din total la nivel naţional). De asemenea, regiunea Bucureşti-Ilfov înregistreaza un număr de unităţi de cercetare şi dezvoltare din România, numai 229, reprezentând 38% din totalul la nivel national.

In ceea ce priveste finantarea cercetarii in Romania in perioada care a trecut de la elaborarea ,,Strategiei Regionale de Inovare’’ alocarea din PIB a fost: in 2007 - 0,56%, in 2008 - 0,75%, in 2009 -0,93%, situatie care nu este deloc imbucuratoare in conditiile in care PIB-ul a fost in scadere mai ales in 2008 si 2009.

Ca un termen de comparatie cu anii anteriori, in 2009 fondurile destinate cercetarii, pentru proiectele in derulare ale principalelor entitati de CDI din tara si anume CNCSIS, CNMP si ANCS au fost diminuate la 35% din totalul celor alocate in anul anterior. 7. POLI DE DEZVOLTARE

TEHNOLOGICA SI CLUSTERE DE FIRME

Polul de industrie TIC. Bucurestiul deţine

rolul de pol absolut al industriei TIC, cu 5810 firme înregistrate (36% din numărul total), 58,460 de persoane ocupate (58% din total) şi o cifră de afaceri de 5.26 miliarde de euro (78%). Accentul in Bucuresti se pune pe sectorul serviciilor, în timp ce producţia de hardware este situata în cea mai mare în zona de vest a tarii (Cluj-Napoca şi Timişoara). Este de remarcat faptul că, în Bucureşti, Cluj-Napoca, Timişoara şi Iaşi există centre universitare specializate de renume in tara nosatra.

Clustere În ceea ce priveşte sectorul de software şi servicii, Bucuresti inregistreaza 64% din cifra totală de afaceri şi 48% din totalul persoanelor ocupate in domeniu. În ceea ce priveste sectorul hardware, Bucuresti generează 50% din cifra de afaceri şi produce 33% din totalul produselor.

Polul din industria mecanica fina. Cu 527 de întreprinderi, în Regiunea Bucureşti-Ilfov concentrează 32% din companiile din cadrul sectorului de mecanica fina (Cod CAEN Rev 2. 33) înregistrată în România. Mai mult, 53% din totalul companiilor din sectorul de mecanica fina, în regiunea Bucureşti-Ilfov genereaza o cifra de afaceri de aproximativ 99,999 RON. Aceasta concentrare de companii din acest sector cu valoare adăugată este sustinuta si prin activitatile inovative ale Institutului National de Cercetare-Dezvoltare în Domeniul Mecanicii fine (INCDMF).


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Prin urmare, se poate spune că, Regiunea Bucuresti-Ilfov este pol al industriei de mecanica fina.

Polul de dezvoltare din sectorul construcţiilor. In sectorul construcţiilor capitala este si ramane una dintre cele mai dinamice zone din România: intreprinderile din Regiunea Bucuresti-Ilfov generau peste 32% (2,821 milioane de euro, în 2005) din cifra de afaceri la nivel naţional nivel în sectorul construcţiilor, mai mult de 41% din valoarea totală brută a investiţiilor in constructii şi peste 34% din valoarea totală a investiţiilor nete, angajand aproape 23% din numărul total de salariaţi din acest sector de mare importanţă şi mărime la nivel national. In prezent insa acest domeniu nu mai are aceeasi amploare fiind ca si economia nationala in recesiune incepand cu sfarsitul anului 2008, accentuandu-se in 2009 si 2010.

Polul din industria maselor plastice. Cu o concentrare de 21% din companiile care activează în sectorul de prelucrare de plastic (din mai mult de 1000 de companii active la nivel naţional), regiunea Bucureşti-Ilfov include, de asemenea, un grup mare de firme din industria maselor plastice. Aceste companii au capital românesc, străin sau mixt.

Centrele de cercetare şi transfer tehnologic în domeniul TIC. Printre institutele de cercetare în domeniul TIC, cea mai importanta este ICI Bucuresti - Institutul National de Cercetare-Dezvoltare pentru Informatica. Alte institute de cercetare şi dezvoltare relevante pentru ITC, electronice si electrice de inginerie domenii sunt amplasate de asemenea, în Bucureşti, de exemplu: Institutul National de Cercetare si Dezvoltare de Micro-tehnologii (www.imt.ro); Institutul Naţional de Studii şi Cercetare pentru Comunicatii (www.cnscc.ro); Institutul National de Proiectare pentru Telecomunicaţii (www.telerom.ro) (înfiinţat în 1952); Institutul National de Cercetari Electronice (ICE), Institutul de Cercetare pentru Inginerie Electrica, ICPE ( www.icpe.ro); Institutul de Cercetare pentru Inginerie Electrica ICPE ACTEL (www.icpe-actel.ro); Institutul de Cercetare şi Proiectare in Automatica, IPA (www.ipa.ro), Institutul de cercetare - echipamente electrice , ICME (www.icpe-me.ro); Institutul ICPE-CA (www.icpe-ca.ro). Centrul de transfer tehnologic în inginerie electronică şi electrotehnică din Regiunea Bucureşti-Ilfov este asigurat de către MINATECH-RO şi CTT-Baneasa. Acesta este parcul ştiinţific şi tehnologic pentru micro şi nanotehnologii, MINATECH-RO Bucuresti, cre a fost înfiinţat prin iniţiativa unui consorţiu naţional coordonat de către Institutul IMT Bucureşti, Universitatea "Politehnica" din Bucureşti şi SC ROMES SA.

Parcul a fost înfiinţat în 2004-2005 şi finanţat de către Programul naţional INFRATECH, gestionat de către Ministerul Educaţiei Cercetării şi Tineretului. Domeniul de activitate specific pentru parc este acela de susţinere a activităţilor din domeniile micro-tehnologii, nano şi micro-inginerie, precum şi dezvoltarea de noi materiale (www.minatech.ro).

Activitatile si serviciile knowledge intensive, specifice economiei globale, se caracterizează prin schimbări rapide de tehnologie, precum şi o creştere continuă a productivităţii, limita între activităţi tradiţionale industriale şi de servicii devine tot mai subtila. Apar asa numitele produse si servicii conexe de asistenta de specialitate pentru afaceri în vederea îmbunătăţirii proceselor de producţie. În acest context, serviciile knowledge intensive devin din ce în ce mai relevante, un factor de creştere a competitivităţii economice. Pe baza definiţiei OCDE, economia bazată pe cunoaştere este acea economie care sustine printre altele, activitatile de cercetare – dezvoltare, consultanta in management, servicii de tehnologia informaţiilor şi comunicaţii, managementul resurselor umane si servicii de ocupare, servicii juridice legate de proprietatea intelectuala, servicii financiare si contabilitate si activitati de marketing. În acest context, Comisia Europeană doreşte să încurajeze dezvoltarea de servicii de inovare, ca motor al inovării pentru întreaga economie europeană, de orientare, în special, cunoştinţe intensive de servicii, fiind identificata ca ramura cu cel mai mare potenţial de inovare in sectorul serviciilor.

8. INOVAREA IN CADRUL

COMPANIILOR Inovarea si activitatile de profil din firmele din România este încă foarte scăzut: peste 80% din numarul de de firme non-inovatoare, alaturi de aproximativ 10% din firmele cu activitati intermitente legate de inovare şi un mic procent al celor strategice inovatoare formeaza totalul pentru tara noastra. Firmele inovative sunt în principal IMM-urile (83,4%) şi operează în principal în industrie (73 %), în timp ce restul sunt active în domeniul serviciilor (comerţ, imobiliare, de transport, tehnologia informatiei şi comunicaţii). Această situaţie este, în mare măsură, rezultatul unui nivel foarte scăzut al finanţării publice pentru inovare, numai 10% din firmele innovative sunt printre cele care beneficiază de finanţare , precum şi niveluri foarte scăzute ale cheltuielilor de inovare, care să nu depăşească 3% din cifra de afaceri a firmele inovative.


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Deşi s-au înregistrat progrese semnificative, în scopul de a încuraja inovarea in ţară, exista inca o slaba cultura legata de acest domeniu.

De aceea, sunt necesare măsuri suplimentare pentru a creşte aplicarea rezultatelor cercetării - dezvoltării şi inovarii in afaceri, pentru a activa acest motor al competitivităţii naţionale, mai cu seama in perioada de criza, cand trebuiesc sustinute investitiile mai ales cele in industrie pentru cresterea productiei si crearea de noi locuri de munca in domenii sustenabile.

Performantele romanesti in CDI, plaseaza tara noastra in grupul tarilor ,,catching-up’’ din UE alaturi de Malta, Lituania, Ungaria, Grecia, Slovacia, Polonia, Portugalia, Bulgaria şi Letonia. În materie de performanţă pentru inovare, Romania a inregistrat progrese semnificative mai mari decât tendinţa mediei UE în ultimii cinci ani. Este relativ slabă însa, crearea de cunoştinţe şi proprietate intelectuală.

Analiza arată că România este relativ eficienta din punct de vedere al sectorului inovare dar ineficienta in cazul aplicarii rezultatelor CDI si a transformarii acestora in proprietate intelectuală. In ultima perioada, tinand cont de mutatiile economice de la nivel mondial Romania, insa, nu valorifica in nici un mod capacitatea de inovare pe care o detine si ca urmare nu poate obtine nici un fel de avantaj competitiv in acest sens.

De altfel in, Raportul Global al Competitivităţii 2009-2010, prezentat de catre Grupul de Economie Aplicata la Forumul Economic Mondial din 2010 evidentiaza faptul ca tara noastra nu sta deloc bine la capitolele infrastructura si inovare. Scorul obtinut de Romania in analiza realizata la nivelul UE27 este cel mai mic.

Figura 3. Romania – Performanta in domeniul CDI, Sursa:European Innovation Scoreboard

Gradul de penetrare a inovarii in randul IMM-urilor din Romania in functie de dimensiunea acestora este prezentat in tabelul urmator: Tabel 2. Activitati inovative in functie de dimensiunea

firmelor Dimensiune

Activitati Inovative

Micro intreprinderi

Intreprinderi mici

Intreprinderi mijlocii

Produse noi 37,59% 47,77% 43,90% Tehnologii noi 23,45% 35,20% 42,28% Noi orientari in managementul si marketing-ul firmelor

19,60% 24,30% 38,21%

Noi sisteme informationale

0,99% 0,84% 0,00%

Activitati neinovative

26,05% 10,06% 8,13%

Sursa: Carta alba a IMM_urilor , 2008 Clasificarea activităţilor de inovare din IMM-uri pe domenii de activitate, se prezinta astfel: - IMM-urile care funcţionează în turism acoperă

cea mai mare parte din totalul întreprinderilor axate pe noi abordări manageriale si de marketing (42,86%).

- IMM-urile care funcţionează în transporturi sunt cele mai interesate de reînnoirea sistemelor lor informatice (4,82%).

- IMM-urile care operează în industrie sunt cele mai interesate in crearea de produse noi (61, 01%).

- IMM-urile care funcţionează în construcţii acoperă cea mai mare parte din totalul de întreprinderi cu accent pe introducerea de noi tehnologii (45,78%).

In general situatia poate fi prezentata precum cea din tabelul de mai jos:


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Tabel 3 .Activitatile Inovative in functie de domeniu Domeniul de activitate Activitati Inovative Industrie Constructii Comert Turism Transport Servicii

Produse noi 61,01% 22,89% 46,77% 34,29% 36,14% 21,56% Tehnologii noi 43,58% 45,78% 21,86% 20,00% 28,92% 26,77% Noi orientari in managementul si marketing-ul firmelor

21,56%

16,87%

19,35%

42,86%

27,71%

29,74%

Noi sisteme informationale

0,46% 0,00% 0,18% 0,00% 4,82% 1,86%

Activitati neinovative 12,84% 20,48% 24,01% 20,00% 12,05% 17,10%

Sursa: Carta alba a IMM_urilor , 2008 9. CONCLUZII

Orientarea actiunilor la nivelul institutiilor de profil politice si nepolitice din tara noastra ar trebui sa fie intreptata spre: - Crearea si implementarea de politici şi programe

pentru îmbunătăţirea transferului de tehnologie catre sectorul de afaceri. Acest lucru ar putea să includa, printre altele, promovarea politicilor de sprijinire a evolutiei existente crearea de " clustere" de sine stătătoare, cu efecte semnificative asupra dezvoltării economice, în special la nivel regional. Astfel de politici trebuie să fie corelate cu măsurile existente de susţinere a polilor de excelenţă şi a reţelelor de afaceri si inovare, precum şi cu cele care au ca scop consolidarea colaborarii universitate-industrie-cercetare-dezvoltare;

- Politici şi programe de sprijin pentru cercetare şi dezvoltare si introducerea conceptului de "universitate antreprenorială" ,în corelare cu priorităţile de dezvoltare regională, pentru care prezenţa unei universitati in cadrul unui cluster sau incubator de afaceri este esentiala;

- Consolidarea colaborării între ANCS şi agenţii de dezvoltare regională pentru elaborarea unui set coerent de politici CDI, structuri şi strategii comune cu mediul de afaceri in scopul mai bunei integrari a cercetarii si inovarii in economia nationala;

- Accesarea de fonduri europene pe Programul de Competitivitate Economica, pentru finantarea proiectelor de cercetare si transfer tehnologic si al inovarii.

BIBLIOGRAFIE [1]. Nicolescu O., (2007) - Carta Albă a IMM-urilor din Romania [2]. Sandu S., ( 2005) - Monitorizare şi analiza CREST-MDC, Proiectul preliminar al politici de cercetare, Grupul mixt de experti interguvernamentali [3]. Directia Generala a Comitetului pentru antreprenoriat (2008) - INNO-Policy TrendChart – [4]. Raportul privind trendurile in cercetare in ROMANIA 2008 [5].Raportul - ANCS ( 2006): Evaluarea sistemului national de CDI si Planul National de inovare [6].Strategia Regionala de Inovare, RO03, Sud-Muntenia [7].Strategia Regionala de Inovare , Ro08, Bucuresti-Ilfov . Quick Info

Market report shows growth for industrial automation electronics IMS Research has published data indicating a strong first-quarter performance for the industrial automation electronics equipment market in 2010, following an estimated revenue decline of more than 14 per cent in 2009. The second half of 2009 showed substantial quarter-on-quarter growth for automation specialists, representing the start of a gradual recovery for the market. In spite of general negative sentiment among many vendors in this sector, IMS Research predicts strong growth for most automation equipment in 2010 and 2011. First quarter 2010 growth will likely have been 25 per cent over that of first quarter of 2009, during which all regional markets experienced the steepest declines. Robust order books developed through both restocking efforts, and new orders are expected to lead to a similarly strong second quarter in 2010. Based on a healthy anticipated first half of 2010, even a flat second half will result in close to double-digit revenue growth for most product areas.


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Adrian Lloyd, IMS Research executive vice president, a co-author of this report, comments: "This is the first time we have consolidated top-level findings from our entire automation portfolio into a single report. It is quite astounding to see that the size of collective revenues accounted for by this market. Not only have we consolidated key data from our own primary research, but also we have compared the results against indices generated from aggregates of quarterly filings of major, publicly-owned industrial electronic vendors. The two sets of data correlate very well, and have generated very interesting findings." After several years of rapid expansion accompanied by double-digit growth rates, the motors and motor controls markets were battered by the economic downturn. However, these markets are poised for a substantial recovery in 2010, with a return to double-digit growth in areas such as AC induction motors, DC brushless motors, motion control equipment, and AC and DC drives projected to help lift overall market growth to more than 8 per cent in 2010. Automation equipment markets, such as PLCs, IPCs and I/O modules, rely heavily on machinery production growth, unlike the motors and motor controls market that also benefits from a large retrofit business. Following an unprecedented contraction of nearly 20 per cent during 2009, IMS Research projects machinery production will enjoy moderate growth in 2010, providing the platform for automation equipment revenues to grow by 7.6 per cent during the same period. The global automation equipment market was estimated to be worth $40.9 billion in 2009, which represents nearly 55 per cent of the total industrial automation electronics equipment market. Although most product markets will experience positive growth in 2010, project-based equipment markets are anticipated to recover more slowly than the other equipment markets. Equipment dependent on greenfield and brownfield projects tend to have longer lead-times, and therefore lag the general economy. Most project-based business equipment, such as medium-voltage motors and drives, and DCS, enjoyed growth in 2009, while all other equipment markets contracted. In effect, therefore, the impact of the recent recession is projected to be felt more profoundly during 2010 in these areas.

Additional findings of the report include: * During the economic downturn the market for industrial automation electronics equipment was estimated to have declined 14.3 per cent in terms of revenues, from $87.4billion in 2008 to $74.9billion in 2009, a decrease of $12.5billion. * The low-voltage AC and DC drives market, estimated to be worth $8.6billion in 2009, managed to outperform the low-voltage induction motors market, thanks in part to the energy-efficiency benefits that drives provide through retrofitting. * The market for PLCs and I/O modules are tied closely to new machinery and, as a result, experienced significant declines during 2009; however, both are predicted to see double-digit growth in 2010. * Sales in Asia Pacific were buffered by China's GDP, which remained positive during 2009. Following the region's strong early recovery from the downturn, it is predicted to grow by 9.6 per cent in 2010, and is forecast to become the largest regional market for industrial automation electronics equipment by 2011. An emphasis in this study has been given to the structure of the industrial automation electronics equipment market. Market share estimates based on 2008 revenues include revenue for industrial automation electrical hardware only, excluding any additional revenues generated through software and services or by any mechanical solution. Additional estimates for both motors and controls and automation equipment by region were also produced as part of the study. For more information, visit www.imsresearch.com (source: http://www.engineerlive.com/Electronics-Engineer/Automation_Control/Market_report_shows_growth_for_industrial_automation_electronics/22665/)


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ICT STRATEGY SUPPORT FOR BUSINESS DEVELOPMENT AND INNOVATION

Nicoleta Gudănescu*, Adrian Nicolau**,

Nicolae Titulescu University, Bucharest, ROMANIA, ** SC AVANGARDE TECHNOLOGIES CONSULTING, Bucharest, ROMANIA,

E-mail:[email protected], [email protected]

ABSTRACT This paper work emphasizes the importance of the strategic management for the present companies, no matter the dimension or the field. More important becomes thou, the implementation and utilization of systems that represents support for business processes and information flows because of focus on co-operation and networking activities of today’s companies. The models created for running businesses are creative but in some cases these are not paying attention to the ICT point of view. There is evidently a large gap between business and technology development and knowledge about those activities. The paper presents the challenges of business and ICT development thorough the strategies, as global strategies of the companies or as units strategies but always have to be handled as integrated and related activities. KEYWORDS: business strategy, development, ICT strategy development, networking, information system,innovation

1. INTRODUCTION The accentuated requirements for effectiveness and competitiveness in today’s business and economy are the main generators of the cooperation and networking activities. Today networking has moved towards strategic enterprise networks (e.g. Jarillo 1993; McHugh et al. 1995; Hines et al. 2000). Cooperation between companies has one main similarity: the need for communication and for information technologies and software support that communication. Information and communication technologies (ICT) have made possible new business models and even new business structures. There are many opportunities for developing business through new processes, models and methods and, of course, with new ICT solutions. On the other hand, some problems could arise, when the business development lives its own life without taking care of real business needs and co-operation aspects.

These kinds of problems are sometimes real in enterprises where business developers follow all the new waves and "trendy" business methods like, in many cases, Customer Relationship Management (CRM) Enterprise Resource Planning (ERP) and Business Intelligence (BI). Other problems arise when developing new methods but neglecting ICT. Of course problems could rise if a company implements a new solution, for example a CRM system, without creating support processes and methods. That’s why the development and implementation of business and ICT should take place concurrently. 2. BUSINESS STRATEGY DEVELOPMENT CHALLENGES Companies are focusing their businesses on some specific area and today many functions are outsourced to co-operation partners. The core business is not always stable. Sometimes customer requirements change and suppliers, too, must change their business.


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There are many examples of organizations which have noticed shortcomings in some areas of competence and which have acquired these competencies through acquisitions or recruitment. A dynamic business environment requires changes in core competencies. Core competence is one aspect of companies' business vision. This vision usually moves as customer requirements and the business environment moves. It depends on the business as to how far ahead the vision states are targeted. Companies should have a vision of the future which serves as the starting point of the business strategy process. After the business target, i.e. the vision state, companies should clarify what they are today. A company needs an analysis of its current state in order to form a clear understanding of the development activities needed. When a company has clarified the vision state and the present state, then it knows the gap in its business. The gap could lie, for example, in production technology, competencies or in know-how. Where the gap lies is always case specific. The development activities needed to fill the gap in business form the roadmap to achieve the vision state and the strategy defines these development activities. The strategy concept itself has been described in many ways. Strategy has its roots in the military and thereafter strategy it has come to mean a definition of goals and objectives (Anthony, 1965). Mintzberg (1987) has defined strategy with 5 "ps": as a plan (rules towards goal), a pattern (mode of behavior), a position (safe place), a perspective (visions and targeting), and a ploy (beating the competitors). Generally, it could be said that strategy relates to corporate strategy, which guides a company as a whole. Porter (1998) has defined five driving forces in industrial competition: Suppliers, Substitutes, Potential Entrants, Buyers and Industry Competitors. Porter, furthermore, has defined three generic strategic approaches to outperforming other companies in industry (Porter, 1998): 1. Overall cost leadership; 2. Differentiation; 3. Focus The many different views of strategy and its development could prove difficult for companies. The challenges in business strategy development could arise in every phase of the development process. The starting point – the targeting and setting of the vision state – could prove very difficult for some companies. If the company has no clear idea what its role in value chain is, it will find it hard to clarify its business vision. The essence of formulating business strategy lies in relating a company to its environment (Porter, 1998). The competitive climate is other relevant aspect when the aim is to develop business strategy.

The key point in business strategy development is to find one's own strengths and to focus on these (Porter, 1998). The identification of one's own strengths is the first step in analyzing one's present state. After a present state analysis, a company can clarify its business strategy by answering the question "What is the path and what actions are needed to reach the vision state from the position of starting development actions today?" The technologies, competition and legislation are changing rapidly, so the strategies should be changed also. Then there are new emerging business models which make business more and more competitive. It is not wise, however, to take all new waves seriously and implement them all in strategy and business. Consultants always bring new ideas and provide their help in implementing new business models. Those models and methods are not good for every kind of business. It is challenging to find the right solutions for one's own business. Today ICT has a significant role in business, and businesses should be due attention to ICT at an early stage of every development activity. 3. TECHNOLOGIC AND ICT STRATEGIES Technology innovations happen almost daily. Technology breakthroughs are speeding up new businesses and enable more effective ways of doing business. Information and communication technology (ICT) is seen to be an enabler but sometimes ICT is also an encumbrance. The implementation of technologies is becoming multidisciplinary and the use of a knowledge base has rapidly increased. Systems interaction has become complex. There are many definitions for ICT and the specialists have defined ICT as the hardware, software, application programs, telecommunication networks and technical expertise that support information processing and communications activities at all levels of a company (Marchand et al. 2001). ICT has had a big impact on product development. Products today are more and more intelligent and it is not a new idea to provide extended products, including tangible and intangible features. The potential sustainable growth of a business lies with services created on the back products. New emerging technologies like smart materials, micro-mechanical sensors and wireless and faster data transfer solutions etc. have presented new opportunities to develop product features, especially those intangible features of extended products and value-added services.


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The advance of technology has created new requirements also for business; the companies should change their operational environments and change is needed for business models and operation models. Technological development is not easy, especially for small- and medium-sized enterprises (SMEs). Technological development needs a lot of effort on the part of a company. It is not easy for the SMEs to utilize new emerging technologies, but it is not easy for bigger companies either. The main point as far as new technologies are concerned is to purposefully create a strategy for ICT in a company. ICT is basically employed at two levels in companies: in operations and products. Both levels are needed for competitive business and both levels need clear understanding of requirements and possibilities. But that is not enough: a company needs vision and a roadmap to advance in ICT development, just as vision and a roadmap are needed in business model development. Organizations, moreover, also need strategies to implement roadmap activities in order to achieve the vision state successfully. The steps a company should execute in strategic ICT planning (Turban et al. 2002) are: 1. Set the IT mission 2. Assess the environment 3. Assess existing systems' availabilities and capabilities 4. Assess organizational objectives and strategies. 5. Set ICT objectives, strategies and policies 6. Assess the potential impacts of ICT At an operations level there are many possible ICT solutions to utilize. Enterprise Resource Planning (ERP) is mostly known as a solution for managing information flows in production. ERP's are used for material management and resource management, but financial aspects can also be managed with ERP. ERP vendors have many different modules and by tailoring these a company can obtain the it wants. CRM systems can manage customer relationships, and PDM (Product Data Management) can be used to manage product-related information. The main point is that ICT should fully support the business processes and the solutions in use should be strategic choices in companies.

Figure 1. Framework of ICT practices in companies

At the highest level of Figure1 are managers and executives, who make the strategic choices, analyze options and formulate business scenarios. All the decisions are made at the highest level and the focus is on management control. At the second level are professionals and technical workers, who act as R&D personnel, product designers, engineers and knowledge workers of the same kind. The common aspect for the second level is that these are normally middle management employees. The third level of the Marchand et al. model includes the process managers, the employees whose responsibilities include the co-ordination of cross-functional or horizontal processes and communication with partners like suppliers and customers. The bottom level represents the operational knowledge workers and supervisors. These people are responsible for the direct operations of company and the processes through which products and services are provided and distributed. All these levels need different kinds of ICT and these levels have four types of ICT practices. According to Marchand, there are three roles or functions that ICT for operational support can play in companies (Marchand et al. 2001): 1. to increase scale efficiencies in the operational activities of manufacturing and service firms; 2. to process basic business transactions; 3. to monitor and record the actions and performance of operational employees in carrying out their tasks. But there is still something wrong in the way companies utilize ICT in business.


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4. THE GAP BETWEEN THE DEVELOPMENT OF BUSINESS AND TECHNOLOGY STRATEGIES

As explained above, companies have mostly two separate ways of developing their businesses: business development and ICT development. Both development activities are strategic choices and they also need strategic decisions. But before clarifying the gap between business and ICT strategies, the relationship between them should first be clarified. Ward and Griffiths (1996) have presented the relationships between business, information system and information technology strategies (Figure 2). Still as we have seen, there is evidently a gap between business and technology development. The companies have their business architecture, the basis for all business. Companies have their chosen business models and structures. This means that companies also need strategy management, which leads the company in the right direction. Companies chosen business models are dependent on their core business. Companies, furthermore, have individual structures, locations, types of organization and so on. The business architecture also includes networking and partnership aspects, i.e. how companies are networked and partnerships created with other companies. All these aspects should be a part of the business vision. The business vision clarifies future aspects, i.e. what the company will be like after few years. The business roadmap therefore clarifies the development path towards the vision state. We need business development activities to make our business more competitive and to fulfil the business vision aspects using the path indicated by the business roadmap. The business architecture is one perspective, but we also have the ICT point of view, which provides the same kind of architecture. The base of the technology architecture has different kinds of enabling technologies and platforms. Companies can have different solutions in use, like ERP or CRM solutions, which are basic or legacy systems. Then there can be some Supply Chain Management (SCM) solutions or Digital Control Systems (DCS) at the floor level, but also different kinds of mobile or remote technologies to support and extend the usage of legacy systems. Companies can have also different kinds of new business tools, for example Business Intelligence solutions to manage business data and information from marketing and customers. Markets are providing a huge number of different solutions to different needs, but there also is much overlapping in systems.

The main idea in ICT utilization in business is that a company needs a technology vision as well as its business vision. Companies should clarify their data administration vision: which kind of solutions best fits the company and what the best solutions for support business are. The present state is usually known, so a company needs to clarify the technology roadmap, i.e. the kind of investments needed to achieve the vision state of technology. After the creating a vision and a roadmap, the company should have a clear idea about the technology development actions required. These were the building blocks of technology architecture. These are the basic elements for competitive business and they should be strategically managed and developed. But there is still a gap between these two strategic development activities. The gap is firstly evident in implementation. Companies do not have a clear idea of how to implement new business models or new enabling technologies. The gap could lie in research and development (R&D), so that companies manage business and ICT separately and the overall business benefits are lost. Companies do not have a common research framework to achieve success both in business and ICT research. One possible gap could be in knowledge and understanding. Companies do not have a clear understanding of business and technology possibilities and requirements. This occurs mostly in big companies with business developers and ICT developers working in own business units. There are few employees and specialists who clearly understand business and technology. Figure 3 below presents ideas on the gap between strategic business and technology development.


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Figure 2. The relationship between business IS and IT Strategies (source: Ward and Griffiths, 1996)

Figure 3. The framework of business and ICT development challenges

These were examples of the gap between technology and business strategy development. Since the gap has been observed, there should be some answer to filling the gap and bringing the business strategy closer to the ICT strategy. 5. SOME IDEAS TO ACHIEVE SUCCESS WITH ICT STRATEGIES There have been many frameworks that have attempted to find the link between ICT strategy and business strategy (for example Parker et al. 1989; Henderson and Venkatraman 1989; 1993; Reich and

Benbasat 1996; Chan et al. 1997). These specialists have presented the same kind of simple strategic alignment model, as presented in Figure 4. This clearly shows the links between ICT and Business strategies and the processes connected with them. On the other hand, several research studies have defined the link between ICT practices and improved organizational decision-making (e.g. Rockart and Bullen 1986).


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Figure 4. Strategic alignment model (Parker et al.

1989; Henderson and Venkatraman 1993). The gap between strategic business development and the ICT strategy could be filled with focused development activities. The main elements in achieving success are common understanding and knowledge sharing. Both business developers and ICT developers should understand each other's areas of expertise. The common understanding should be at many levels within organizations, not only at management and executive levels but also in at development and realization levels. The strategy process requires knowledge and participation from many levels of organizations and also from different business units. Co-operation between business and ICT departments of organizations is the one key to success. But co-operation may be hard to realize, if there are no common processes. Organizations should make connections between business and ICT planning processes, and from there to operation levels. Another element in achieving success is implementation. ICT should be successfully implemented, but organizations should also implement the right solutions, the ones that best fit their own businesses. ICT and business operations have great potential for each other, if successfully implemented. Follow-up and evaluation of implementation is the answer to estimating the success of implementations. Any evaluation must also take further development needs into account. 6. CONCLUSIONS Business development at the strategic level is not an easy task for companies, especially for SMEs. Business strategies change and companies should change their competencies in value chains. A strategy should clarify the methods and activities required of a changing business.

The utilization of different ICT solutions requires understanding of the business environment and business requirements, and also of market opportunities. The other aspect is the understanding of ICT solution providers. There are many solutions on the market that sound great, but after implementing these solutions difficulties could arise. In many cases the solutions are not capable of doing the things the marketing people had claimed. Or there may be a need for expensive modifications to fit solutions to their intended use. Success could be achieved through focused development activities, starting with an analysis and continuing through development to implementation and evaluation. This paper has presented the main ideas of a future doctoral thesis. The next phase is going to focus on research. The evolution of industrial service business is interesting topic, as Finnish companies are focusing on providing value-added services for their products. The concept of the extended product is not enough; companies are responding more to customers' processes REFERENCES [1]. Anthony, R. - Planning and control systems, a Framework for Analysis. Boston: Harvard University Press, 1965, p 96. [2]. Chan, Y., Huff, S., Barclay, D., Copeland, D. - Business Strategic Orientation, Information Systems Strategic Orientation and Strategic Alignment. Information Systems Research, 1997, 8 (2): 125-150. [3]. Child, J. & Faulkner, D. - Strategies for Cooperation. Managing Alliances, Networks, and Joint Ventures. Oxford: Oxford University Press, 1998. [4]. Henderson, J., Venkatraman, N. - Strategic Alignment: A Framework for Strategic Information Technology Management. Center for Information Systems Research, Working Paper No. 190, Massachusetts Institute of Technology, Cambridge, 2000. [5]. Henderson, J., Venkatraman, N. - Strategic Alignment: Leveraging information technology for transforming organizations. IBM Systems Journal, 193, 32 (1), 4-16. [6]. Kaplan, R., Norton, D. - The Strategy-Focused Organization: How balanced Scorecard Companies Thrive in the New Business Environment. Harvard Business School Press, 2000. [7]. Marchand, D., Kettinger, W., Rollins, J. - Information orientation - The link to Business Performance. Oxford University Press, USA, 2001. [8]. Mintzberg, H. - The Strategy Concept 1: Five Ps for Strategy. California Management Review (30, 1, June 1987:11-24), 1987. [9]. Nonaka, I. J., Takeuchi, H. - The Knowledge-Creating Company. How Japanese Companies Create the Dynamics of Innovation. New York: Oxford University Press, 1995. [10]. Porter, M. - Competitive Strategy - Techniques for analyzing industries and competitors. New York: The Free Press, 1998. [11]. Reich, B., Benbasat, I. - Measuring the link between Business and Information Technology Objectives. MIS Quarterly, Mar.: 55-82., 1996. [12]. Ward, J., Griffiths, P. - Strategic Planning for Information Systems, 2 nd. Ed. Chicester: Wiley, 1996.


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THE CORRELATION BETWEEN THE STUDIES IN THE FIELD OF INFORMATION TECHNOLOGY

AT THE LEVEL OF THE ERP PROGRAMS AND THE PROGRESS OF THE INDUSTRIAL TEHNOLOGICAL

MANAGEMENT

Andronie Maria, Băluţă Aurelian Virgil

Spiru Haret University, Bucharest, ROMANIA, e-mail: [email protected]

ABSTRACT One of the improvement trends of the industrial process management consists in using on an increasingly large scale the tools provided by computer science. Basically there is a continuous improvement of the information tehnologies and they permanently adapt to specific processes. Certain evolutions have the tendency to become precious conceptual generalizations or to engender an infrastructure specific to a new era, that of knowledge. In this article we stress the utility of the information technology studies in general and concerning the ERP programs in particular for the technological management processes of the industrial processes. REZUMAT Una din direcţiile de perfecţionare a managementului proceselor industriale o constituie utilizarea pe scară tot mai mare a instrumentelor oferite de informatică. Practic are loc perfecţionarea permanentă a tehnologiilor informaţiei şi adaptarea acestora la procese particulare. Unele evoluţii tind spre generalizări conceptuale valoroase sau spre generarea unei infrastructuri specifice unei noi ere, a cunoaşterii. În acest articol punem în evidenţă utilitatea în procesele de management ale unor teme sau direcţii de cercetare din tehnologia informaţiei.

KEY WORDS : Information technology, Echnological management, ERP programs, Industrial processes. CUVINTE CHEIE : tehnologia informaţiei, management tehnologic, programe din clasa ERP, procese industriale.

1. RESEARCH SUBJECTS

AND TRENDS IN THE INFORMATION TECHNOLOGY AT THE CONCEPTUAL LEVEL WITH AN APPLICATION IN THE INDUSTRIAL PROCESS MANAGEMENT

A range of research subjects and trends in

the information technology aims at improving the system of concepts necessary to the development in

point of application. It is a part of the fundamental research and connects on the one hand with industrial branches such as automatics or automatizations, computer science, but also with knowledge theory, general economy (the knowledge economy and informational economy issues), cybernetics and the theory of systems.

We can see in table 1 the research subjects or trends as well as their implications on the industrial process management. Wherever necessary there are also related remarks.


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Table 1.Research subjects and trends in the information technology at the conceptual level

with an application in the industrial process management No. crt.

Research subjects/fields in the information

tehnology

Implications on the industrial process management

Remarks

0 1 2 3

1 The ERP software platform concept (Enterprise Resource Planning):.

We provide the development of the fundamental researches at the concept level that may allow the progress at the application level according to the technological process nature; we analyze specific objectives and functionalities, module category, hardware- software infrastructure, integration and use methods, the correlation between the computer science solutions and the functionalities-performances combination;

It is a multidisciplinary and multi-application subject, both in the industrial process management and in the information or processing administration;

2 The integrated computer system concept

We analyze the ERP management system parameters (Enterprise Resource Planning) for the bussiness administration with financial-accounting and management decision assisting components: arhitecture, objectives, performance characteristic features, implemention methods and development possibilities, solutions and applications incorporated in the system , advantages and disadvantages provided to the bussiness environment;

We emphasize the advantages and disadvantages provided to the technological management by the ERP programs (conceptual level)

3 Information technology procedure

We simulate a set of internal procedures for performant sysems of information technology integrable to the procedure system of the companies based on governance and high work degree based on procedures

The technological management can not be carried out outside the company’s procedure system;

4 Dedicated computer system concept

We analyze design techniques, analysis methods, implementation methods and development opportunities, with the specific characteristic features, advantages and disadvantages.

We can do pertinent comparisons between the computer system option and other technologically possible variants;

5 The concept of computer system distributed in the Web environment

We analyze: specific architectures, performance characteristic features, specific achievement features (analysis, design, implementation) and development, solutions and applications incorporated in the system;

The result consists in comparisons between the advantages and disadvantages for the technological management;

6 Integrated computer system functioning for the management;

We analyze the operation of the IT systems hat cover all the processes carriedout in an economic organization (including the tehnological ones), no matter what the activity field may be (production, services, trade); the computer solution is an ERP-type ;

The pieces of information concerning the integrated systems for management are operational and directly applicable for the technological management;


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No. crt.


tehnology

Implications on the industrial process management

Remarks

0 1 2 3

7 The web application concept

We analyze representative characteristic features, accomplishment and development peculiarities (analysis, design, implementation), applicability fields, advantages and disdvantages specific to the web applications incorporated in the computer systems also designed for the technological management,

The technological management can set specific objectives and functionalities, to the web applications incorporated in the ERP platforms

8 Data Bases Administration Systems ( SGBD);

We analyze the SGBD performances; we take into acount those with a high level of scalability and possibilities to adapt to the requirements of the various categories of users, supported by the digital, multimedia and communication technology;

We perform the comparative analysis of the various technological variants or within the same technological level;

2. RESEARCH SUBJECTS AND

TRENDS IN THE INFORMATION TECHNOLOGY TO AN OPERTIONAL LEVEL

WITH AN APPLICATION IN THE INDUSTRIAL PROCESSES MANAGEMENT

Another range of research subjects and

trends in the information technology aims at developments to an operational level with an application in the industrial processes management.

These subjects can be included in the

applicative research. While elaborating them we need contributions from outside the information technology both in the study development stage and in the testing and experimental stage.

We can see in table 2 the research subjects or trends in the information technology with an application in the industrial process management as well as their implications on the industrial process management.

Table 2. Research subjects and trends in the information technology at an operational level with an application in the industrial process management

No.

crt.


technology

Subject content of the researhes Implications on the industrial process management

1 Advanced data analysis

Data Warehousing and OLAP, data mining and discovering the knowledge out of the data, data mining techniques integrated in the ERP platforms,

The technological management of the industrial processes can perform the comparative analysis of the data mining tools placed at the disposal by various computer applications

2 Integrated management computer systems.

.

We carry out the seting of objectives and specific functionalities, technical and functional characteristic features, including the necessary technological support (the hardware- software infrastructure), achievement methods (analysis, design, implementation) and development possibilities, main component modules;

Based on these researches the technologial management can accomplish a comparative analysis of the possible solutions, including the identification of the operational technical and functional advantages and disadvantages;


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No.

crt.


technology

Subject content of the researhes Implications on the industrial process management

3 Systems with advanced data bases.

Advance data patterns. Advanced application with knowledge bases.

The comparative analysis in the case of the various computer applications.

4 Advanced computer technologies:

We set characteristic features, use possibilities in accomplishing integrated organizational computer systems;

The technological management shall set an evaluation pattern of the advantages and disadvantages of the various options on the IT market;

1. RESEARCH SUBJECTS

AND TRENDS IN THE INFORMATION TECHNOLOGY WITH MULTIDISCIPLINARY DEVELOPMENTS AND APPLICATION IN THE INDUSTRIAL PROCESS MANAGEMENT

An important set of research subjects and trends in the information technology aims at developments having a strong multidisciplinary

character, usually closely connected both to the technological management and to the administration activities. In all these subjects the component part efficiency of the industrial processes or of the technological innovation is an intrinsec part. A broaden enumeration of these subjects can be found in table 3.

Table 3. Research subjects and trends in the information technology with multidisciplinary developments and application in the industrial process management

No.

crt.

Research subject Interference fields

1 ERP platforms used in the integrated processing and advanced analysis of large and very large volumes of data stocked in the data bases of the economic organizations having a complex activity field. Case studies for the applications available on the IT market at a certain moment.

It becomes possible to integrate the data from complex technologies to which severe restrictions are annexed as well as pieces of information from the data bases for management, commercial function or activity administration, including the programming and program follow-up elements;

2 The cost-benefit analysis when implementing informatic technologies and ERP platform in the integrated processing and in the advanced analysis of the data stocked in the data bases of the economic organizations in the case of the option for the various applications available on the market.

Without including the cost-benefit analysis any decision, as correct as it may be from a technological perspective, risks to cause waste;

3 The performances of modern management of the costs caused by the evolution of the digital, multimedia and communication technology;

We analyze the connexion between the administration and the management of the company resources from the perspective of the costs with the technological performance promoted by the process informatization;

4 The comparative analysis of the characteristics and specific features for processing the data engendered by the various categories of activities

We perform a shaping of the informatization capacity of the various categories of economic activities with the purpose of setting optimum


75

No.

crt.

Research subject Interference fields

carried out by the economic bodies. economic and technological level of the informatization degree;

5 The use of the various program packages when taking over from the companies’ accounting information system the necessary data for elaborating the decisions concerning the contribution of the innovative elements within the processes.

We provide the connection of the informational flows of the company with the purpose of setting the innovation degree of the processes, the parameters of the innovative activities, the correlation between innovated and economic performance; the study is made with the help of certain tools specific to each available program package;

6 The use of the various program packages when taking over from the companies’ accounting information system the necessary data for knowing the costs with the labor force, the total costs and the competitiveness;

We analyze the connection between technologies and the essential consumptions of the company; it is a correlation for which there are several empiric data than mathematical pattern calculation; the study is made with the help of some tools specific to each available program package;

7 The use of the various program packages when taking over from the companies’ accounting information system the necessary data for the substantiation of the sustainable development politics and those of environment management.

The study is made with the help of some tools specific to each available program package;

8 The use of the various program packages when taking over from the companies’ accounting information system the necessary data for knowng and monitoring the investment politics

The technological management of the companies has a vital need to know the investing and disinvesting processes as well as the connections with the prgresses in the company life; the study is made with the help of some tools specific to each available program package;

9 The use of the various program packages when taking over from the companies’ accounting information system the necessary data for knowing the stage related to the compliance with legislation and policies concerning occupational health and security.

The technological modifications must be applied when inappropriate evolutions concerning the occupational health and security occur; the study is made with the help of some tools specific to each available program package;

4. CONCLUSION The correlation between the studies in the

field of information technology at the level of the ERP programs and the progress of the industrial tehnological management is represented by: research subjects and trends in the information technology at the conceptual level with an application in the industrial process management, research subjects and trends in the information technology to an opertional level with an application in the industrial processes management, research subjects and trends in the information technology with multidisciplinary developments and application in the industrial process management.

REFERENCES

[1].Zenovie Gherasim, Andronie Maria: Managementul proiectelor, Bucureşti , Editura Fundaţiei "România de Mâine", 2010, ISBN 978-973-163-556-9. [2]. Băluţă Aurelian Virgil: The importance of perfecting methods concerning parameters of cost budgets in metallurgy, Metalurgia International, 2/2008; [3].Site www.wizrom.ro [4].Site www.totalsoft.ro [5].Site www.bitsoftware.ro [6].Site www.ciel.ro.


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