2015 Proceedings of the 7th Information Technologies in Environmental

Engineering International Conference

14th to 16th July 2015

Summerstrand Hotel, Port Elizabeth, Nelson Mandela Bay, South Africa

http://itee2015.org/

Editors: Dr Brenda Scholtz Prof Dr.-Ing. habil. Jorge Marx Gómez Mr Clayton Burger ISBN: 978-1-920508-60-9

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Proceedings of the 2015 Information Technologies in Environmental Engineering International Conference Published by the Nelson Mandela Metropolitan University, Port Elizabeth, South Africa All rights reserved Copyright © 2015 Nelson Mandela Metropolitan University, South Africa No part of this document may be commercially reproduced or transmitted in any form or by any electronic, photographic or mechanical means, including photocopying and recording on sound, tape or laser disk, on microfilm, via the Internet, by E-mail, or by any other information storage and retrieval system, without written permission from the authors of the articles. Educational, research and personal use is permitted on condition that the articles are not edited in any way. First edition 2015 ISBN 978-1-920508-60-9 Conference Logo Design by Caylee Greyvenstein Editing by Brenda Scholtz, Jorge Marx Gómez and Clayton Burger Editing assistants: Maxine Esterhuyse and Samantha Ludick

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Editorial Information Technologies in Environmental Engineering (ITEE) is a biennial conference hosted by a new university every second year. The conference aims to bring leading researchers in IT-enabled environmental engineering related disciplines together to share novel research, current studies and potential for future collaboration. The theme of ITEE 2015 is ‘Technologies for a sustainable future’. The review committee for the conference was comprised of well-regarded local and international members of the academic computing community, having expertise and interest in subjects relevant to the theme of the conference. A total of 33 academics reviewed papers for the conference; of these 27 were international academics and 6 were South African academics. All contributed papers were screened, and identifying author information was redacted prior to the initiation of the review process. The review process followed the double-blind peer review model. Every paper received multiple reviews, and the programme chairs solicited additional expert reviews in cases where further clarity was warranted. Reviewers were requested to especially consider the originality of contributions, relevance to the conference, technical/scientific merit as well as presentation and clarity. A total number of 31 academic papers were received for consideration for the conference. The double-blind review process was highly selective, resulting in 13 full papers and 5 work-in-progress papers being accepted for presentation at the conference after the required changes were made. This constitutes a 58% acceptance rate of contributed papers. Of the 13 accepted full papers, 7 are from European institutions and 6 papers are from South African universities. The papers accepted cover a wide range of relevant topics within the conference theme, and are reproduced within these proceedings. Dr Brenda Scholtz, Prof Dr.-Ing. habil. Jorge Marx Gómez and Mr Clayton Burger Editors July 2015

Organising Committee

Conference Co-Chairs Prof Dr.-Ing. habil. Jorge Marx Gómez (Universität Oldenburg) Dr Brenda Scholtz (NMMU)

Proceedings Editor & Webmaster Mr Clayton Burger (Universität Oldenburg)

Assistant Editors Ms Samantha Ludick and Ms Maxine Esterhuyse

Technical Committee Chair Dr Kevin Naude (NMMU)

Programme Coordinator Dr Lester Cowley (NMMU)

Committee Members Prof Andre Calitz (NMMU) Prof Jean Greyling (NMMU)

Assistant Committee Members

Ms Kerryn Botha (NMMU) Ms Bianca Deyzel (NMMU) Ms Mareike Hinrichs (Universität Oldenburg) Ms Hayley Irvine (NMMU) Ms Maxine Esterhuyse (NMMU) Ms Samantha Ludick (NMMU)

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Programme Committee We acknowledge the role of the following people who were part of the review process: Sedef Akinli Kocak (Ryerson University) Javier Britch (Universidad Tecnológica Nacional de Córdoba) Christian Bunse (Fachhochschule Stralsund) Clayton Burger (Universität Oldenburg) André Calitz (Nelson Mandela Metropolitan University) Lester Cowley (Nelson Mandela Metropolitan University) Clemens Düpmeier (Karlsruhe Institute of Technology) Holger Eichelberger (Universität Hildesheim) Nils Giesen (Universität Oldenburg) Albrecht Gnauck (Hochschule für Technik und Wirtschaft Berlin) Marion Gottschalk (Oldenburger Institut für Informatik) Sebastian Götz (Technische Universität Dresden) Klaus Greve (Universität Bonn) Jean Greyling (Nelson Mandela Metropolitan University) Theo Härder (Technische Universität Kaiserslautern) Timo Hönig (Friedrich-Alexander-Universität Erlangen-Nürnberg) Naoum Jamous (Universität Magdeburg) Horst Junker (Institut für Informationsmanagement) Gamal Kassem (Universität Magdeburg) Veit Köppen (Universität Magdeburg) Oliver Kramer (Universität Oldenburg) Wolfgang Lohmann (Universität Zürich) Siba Mohammad (Universität Magdeburg) Kevin Alexander Naudé (Nelson Mandela Metropolitan University) Stefan Naumann (Hochschule Trier, Umwelt-Campus Birkenfeld) Birgit Penzenstadler (University of California, Irvine) Rafael Bello Perez (Universidad Central "Marta Abreu" de Las Villas) Brenda Scholtz (Nelson Mandela Metropolitan University) Thomas Schulze (Universität Mannheim) Michael Sonnenschein (Universität Oldenburg) Jean-Paul Van Belle (University of Cape Town) Ute Vogel (Universität Oldenburg) Volker Wohlgemuth (Hochschule für Technik und Wirtschaft Berlin)

ITEE 2015 Corporate Sponsors

The Organising Committee would like to express its grateful thanks to the generous sponsors of ITEE 2015:

SYSPRO (Platinum Sponsor) REDISA (Platinum Sponsor) PwC (Silver Sponsor) Allan Gray (Bronze Sponsor)

Telkom

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Contents

FULL ACADEMIC PAPERS Pg

SESSION 1:

Contribution of Mobile Phones to Township Livelihood Outcomes in the Western Cape Province of South Africa Unathi September, Upendo Fatukubonye, Kevin Johnston and Brian O’Donovan

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An Application to Support Sustainability Management in the Cuban Energy Sector Frank Medel-González, Lourdes García-Ávila and Jorge Marx Gómez

16

A Framework for Environmental Management Information Systems in Higher Education Brenda Scholtz, André Calitz and Blessing Jonamu

29

Support for Improved Scrap Tire Re-use and Recycling Decisions Matthias Kalverkamp and Alexandra Pehlken

42

SESSION 2:

Risk Profiling for Corporate Environmental Compliance Management Heiko Thimm

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Designing for Engagement – A Case Study of an ICT Solution for Citizen Complaints Management in Rural South Africa Carl Jacobs, Ulrike Rivett and Musa Chemisto

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SESSION 3: Industry Presentations (not included here)

SESSION 4:

An Analysis of the Perceived Benefits and Drawbacks of Cloud ERP Systems: A South African Study Brenda Scholtz and Denis Atukwase

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Collaborative Network Platform Solution for Monitoring, Optimization, and Reporting of Environmental and Energy Performance of Data Center Gamal Kassem, Niko Zenker, Klaus Turowski and Naoum Jamous

91

Using Social Media to Improve Environmental Awareness in Higher Education Institutions Brenda Scholtz, André Calitz and Thabo Tlebere

102

Sustainability Reporting by South African Higher Education Institutions André Calitz, Margaret Cullen and Samuel Bosire

115

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SESSION 5:

A Living Lab for Optimising the Health, Socio-Economic and Environmental Situation in El Salvador Melanie Platz, Marlien Herselman and Jörg Rapp

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Modeling the Intention to Use Carbon Footprint Apps Arno Sagawe, Burk¬hardt Funk and Peter Niemeyer

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Mass Customization – Sustainability of a Computer-Based Manufacturing System Hans-Knud Arndt

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M&D SYMPOSIUM PAPERS

SESSION 6:

A Data Replication Protocol for Real-World Network Topologies Robert Schadek and Oliver Theel

168

Intelligent Management of Energy Usage in a Home Environment Cainos Mukandatsama, Janet Wesson and Brenda Scholtz

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The Prospects and Approaches of Greening Sub-Saharan African Universities Lloyd Larbi, Jorge Marx Gómez, José Luís Sambo, Eugénio Alberto Macumbe and Jantje Halberstadt

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Region-Adherent Distributed Algorithms in Faulty Environments Dilshod Rahmatov and Oliver Theel

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A Business Intelligence Framework for Supporting Sustainability Information Management in Higher Education Institutions Ross Haupt, André Calitz and Brenda Scholtz

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Conference Programme

Tuesday 14 July 2015 (Pre-Conference Activities)

TIME EVENTS 18:00 – 20:00 Registration and Welcoming Function (Pool Lounge)

Wednesday 15 July 2015 – DAY 1 (Conference Opening and Academic, Competition and Industry

Presentations)

TIME EVENTS 08:30 – 09:00 Registration (Pool Lounge)

Conference Opening (Conference Room) 09:00 – 09:15 Conference Welcome: Prof Andrew Leitch (DVC Research, NMMU)

09:15 – 09:50 Keynote Address: Professor Emilio Luque - Modelling, Simulation, Prediction and Computation The Role of Computation (HPC) to Improve the Quality of the Results of Simulation When Computation is Used to Provide the Best Possible Value for the Models' Parameters.

Parallel Session 1a: Computing for Sustainability With Respect to Societal Impact (Conference Room) Session Chair: Prof Ulrike Rivett (UCT)

Parallel Session 1b: Computing for Sustainability With Respect to Organisational Impact (Meeting Room 2 & 3) Session Chair: Prof Dr Hans-Knud Arndt (Universität Magdeburg)

10:00 – 10:30

Contribution of Mobile Phones to Township Livelihood Outcomes in the Western Cape Province of South Africa. Unathi September, Upendo Fatukubonye, Kevin Johnston and Brian O’Donovan. UCT

Application to Support Sustainability Management in Cuban Energy Sector Frank Medel-González, Lourdes García-Ávila and Jorge Marx Gómez. Universidad Central "Marta Abreu" de Las Villas and Universität Oldenburg

10:30 – 11:00

A Framework for Environmental Management Information Systems in Higher Education. Brenda Scholtz, Andre Calitz and Blessing Jonamu. NMMU

Support for Improved Scrap Tire Reuse and Recycling Decisions. Matthias Kalverkamp and Alexandra Pehlken. Universität Oldenburg

11:00 – 11:15 COFFEE BREAK (Pool Lounge)

Parallel Session 2a (Conference Room) Session Chair: Prof Dr.-Ing. Jorge Marx Gómez (Universität Oldenburg)

Parallel Session 2b (Meeting Room 2 & 3) Session Chair: Prof Jean Greyling (NMMU)

11:15 – 11:45 Risk Profiling for Corporate Environmental Compliance Management. Heiko Thimm. Pforzheim University (by proxy)

Student Project Competition Presentations: Improving Society or the Environment Using the Internet of Things (IoT)

11:45 – 12:15

Designing for Engagement – A Case Study of an ICT Solution for Citizen Complaints Management in Rural South Africa. Carl Jacobs, Ulrike Rivett and Musa Chemisto. UCT

Session 3a: Computing for Sustainability with Respect to Organisational Impact (Industry Symposium Part 1, Conference Room). Session Chair: Dr Brenda Scholtz (NMMU)

12:15 – 12:45 A Practical Application of Information Technology in the Waste Management Sector. Ian Beaton. CIO REDISA

12:45 – 13:15 Functional Programming in the Corporate Environment. Benny Ou. Allan Gray

13:15 – 14:00 LUNCH (Satis Restaurant)

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Wednesday 15 July 2015 – DAY 1 (continued) (Conference Opening and Academic, Competition and Industry

Presentations)

Session 3b: Computing for Sustainability with Respect to Organisational Impact (Industry Symposium Part 2, Conference Room). Session Chair: Dr Brenda Scholtz (NMMU)

14:00 – 14:30 GRI Framework for Sustainability: Empowering Decision Making. Douglas Kativu. GRI Africa

14:30 – 15:00 Making Integrated and Sustainability Reporting Practical for Organisations. Jayne Mammatt. Partner. PwC

15:00 – 15:30 Market Trends and Technological Innovations in Integrated Reporting. Johan Naudé and Daniel Da Silva. KPMG

15:30 – 16:00 Organisational Impact and Value Add – Recycling Case Studies. Jaisheila Rajput. CEO. Tomorrow Matters Now | TOMA-Now

19:00 – 23:00 Gala Dinner and Best Paper and Student Competition Awards (Lillie’s Bar)

Thursday 16 July 2015 – DAY 2 (Academic and Post-Graduate Presentations)

TIME EVENTS 08:30 – 09:00 Keynote Address: SYSPRO Presentation.

Session 4 (Conference Room) Session Chair: Dr Melanie Platz (Universität Koblenz-Landau)

09:00 – 09:30 An Analysis of the Perceived Benefits and Drawbacks of Cloud ERP Systems: A South African Study. Brenda Scholtz and Denis Atukwase. NMMU

09:30 – 10:00 Collaborative Network Platform Solution for Monitoring, Optimization, and Reporting of Environmental and Energy Performance of Data Center. Gamal Kassem, Niko Zenker, Klaus Turowski and Naoum Jamous. Universität Magdeburg

10:00 – 10:30 Using Social Media to Improve Environmental Awareness in Higher Education Institutions. Brenda Scholtz, Andre Calitz, NMMU and Thabo Tlebere. SYSPRO

10:30 – 11:00 Sustainability Reporting by South African Higher Education Institutions. Andre Calitz, Margaret Cullen and Samuel Bosire. NMMU

11:00 – 11:30 COFFEE BREAK (Pool Lounge)

Session 5 (Conference Room) Session Chair: Prof Kevin Johnston (UCT)

11:30 – 12:00

A Living Lab for Optimising the Health, Socio-Economic and Environmental Situation in El Salvador. Melanie Platz, Marlien Herselman and Jörg Rapp. University of Koblenz-Landau and University of South Africa

12:00 – 12:30 Modeling the Intention to Use Carbon Footprint Apps. Arno Sagawe, Burkhardt Funk and Peter Niemeyer. Leuphana University

12:30 – 13:00 Mass Customization – Sustainability of a Computer-Based Manufacturing System. Hans-Knud Arndt. University of Magdeburg

13:00 – 14:00 LUNCH (Satis Restaurant)

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Thursday 16 July 2015 – DAY 2 (continued) (Academic and Post-Graduate Presentations)

Session 6: Postgraduate Symposium (Conference Room) Session Chair: Prof Jean Greyling (NMMU)

14:00 – 14:20 A Data Replication Protocol for Real-World Network Topologies. Robert Schadek and Oliver Theel. Universität Oldenburg

14:20 – 14:40 Intelligent Management of Energy Usage in a Home Environment. Cainos Mukandatsama, Janet Wesson and Brenda Scholtz. NMMU

14:40 – 15:00 The Prospects and Approaches of Greening Sub-Saharan African Universities. Lloyd Larbi, Jorge Marx Gómez, José Luís Sambo, Eugénio Alberto Macumbe and Jantje Halberstadt. Universität Oldenburg

15:00– 15:20 Region-Adherent Distributed Algorithms in Faulty Environments. Dilshod Rahmatov and Oliver Theel. Universität Oldenburg

15:20 – 15:40 A Business Intelligence Framework for Supporting Strategic Sustainability Information Management in South African Higher Education Institutions. Ross Haupt, André Calitz and Brenda Scholtz. NMMU

16:00 – 16:30 Closing Address (Conference Room)

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Region-Adherent Distributed Algorithms in

Faulty Environments

Dilshod Rahmatov, Oliver Theel17

Abstract This research work is exploring a new class of fault-tolerant distributed

algorithms based on a concept which is called region-adherence. A region-

adherent algorithm upper-bounds the violation of safety due to faults in space.

With bounding in space, it is meant that the decrease of the quality of service that

the system provides to its environment is upper-bounded per fault. This paper

presents a brief introduction, focusing on a particular property of the self-

stabilisation concept and a new concept called region adherence that is somewhat

“orthogonal” to the property of self-stabilisation. The paper then presents a formal

definition of region adherence, the status of the research work done so far as well

as ideas for further work.

1 Introduction

Self-stabilising systems are famous realisations of non-masking fault-tolerant

systems. Such systems are always live, but due to faults or improper initialisation,

may not be safe. However, because of its “inner design,” a self-stabilising system

– as long as it is not in a state from whereon it exhibits safe behavior –

autonomously works towards establishing or re-establishing this safe behaviour.

Importantly, it does so in an upper-bounded number of execution steps (in the

absence of newly occurring faults), a property called convergence (Fig. 1). Thus,

one can regard self-stabilising systems as systems that limit the invalidation of

their safety property in time. An alternative, though, of restricting the invalidation

of the safety property in time is restricting it in space. We refer to such systems as

region-adherent systems (Becker et al. 2013). In contrast to self-stabilising

systems which are clearly non-masking fault-tolerant systems, region-adherent

systems can be realised as either being masking or non-masking.

D. Rahmatov, O. Theel

Carl von Ossietzky Universität,

Oldenburg, Germany

e-mail: dilshod.rahmatov@informatik.uni-oldenburg.de; theel@informatik.uni-oldenburg.de

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Fig. 1. Behavior of a Self-Stabilising System over Time

2 Notion of Region-Adherence

A region-adherent system can be perceived as a system exhibiting a particular

variant of gracefully degrading behavior (Herlihy and Wing 1987): it gracefully

degrades the service quality provided by the system per fault up to some maximal

number of faults that the system is able to withstand. Additionally, degradation is

upper-bounded per fault. With service quality, we refer to an application-specific

quality-of-service notion that is without faults, where the system delivers a service

with 100% quality. When faults occur the service quality gets increasingly

reduced. A region-adherent system exhibits desirable fault tolerance properties.

When region-adherence is realised in a system, it manifests gracefully degrading,

quantified quality-of-service guarantees in case up to f faults happen. Thus, at any

time knowing the number of faults that have happened, the system user can take

an a priori known minimal service quality for granted that is crucial information

in various critical contexts.

Clearly, a system that is live and safe should provide the system service the

user is interested in. In this case, we assume that the system is delivering 100% of

service quality. For example, when watching the video image which is transmitted

through the telecommunication equipment (satellites, receivers, and others), the

video quality may be reduced due to the faults encountered in the encoding,

decoding processes, or even due to bad weather conditions (Anand et al. 2000).

However, in such a case the video image can be still available with a reduced

quality. A particular behaviour of such systems over time is given in Fig. 2. The

dashed blue line shows the service quality of a region-adherent system. The solid

blue line states the minimal service quality guaranteed by the system. Initially, the

system is in a safe state. In a safe state, the system delivers 100% of service

quality. After the first fault has occurred, the system must deliver a service quality

of at least 100% − δ. The dashed blue line exhibits a slightly higher service

quality. This is always allowed. After the second fault, the guaranteed and

delivered service quality is again reduced and so on. Assuming a maximal service

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quality reduction per fault of δ = 30%, then the system is able to “survive” three

faults (of the underlying fault model) and is still able to provide a system service

above 0%, here, a “residual” quality of at least r = 10%. The dashed blue line

indicates a possible run of the system, represented by the actual service quality

provided at a particular time. Note, that in the example run given, the system could

survive more faults and still deliver a service quality of greater than 0% (although

only with maximal service quality reduction of less than 10%), but without any a

priori known minimal service quality above 0%. Fig. 3 shows a topological

interpretation of the behavior of a region-adherent system. The blue dashed line

represents a particular execution of the region-adherent system over time.

Execution starts in the innermost region where the system exhibits 100% of

service quality. When the first fault occurs, then the system is thrown in a state of

the neighboring region with 100% − δ service quality only. After a second fault,

the system is allowed to adopt system states belonging to any of the three

innermost regions, thereby exhibiting a system quality of 100% − 2 · δ minimum.

When being in a particular region, without any further fault, the system is allowed

to stay within the region it is currently in, as well as any included region. In this

sense, the system behavior is restricted in space: is must adhere to regions of

known system quality. We formally defined the notion of region-adherence as

follows:

Definition 1 (General Region-Adherence (Becker et al. 2014a)). Assume a

system with configurations C, initial configurations C0 and algorithm A under

fault model F. Let g: C → [0, 1] be a function stating the service quality of the

system and let f be a natural number. r: {0, . . . , f } → [0, 1) is a non-decreasing

function with r(0)=0 and r( f ) < 1. Algorithm A is called f - region-adherent wrt.

g, r, and F, if and only if for all reachable configurations c ∈ C, all initial

configurations c0 ∈ C0 and all executions γ = c0 … c ending in c with #F\A (γ ) ≤ f ,

the following holds:

g(c) ≥ 1 – r(#F\A(γ)) (1)

where #F\A(γ) represents the number of fault steps of execution γ. A system

executing an f -region-adherent algorithm is also called f -region-adherent.

A fault (step, i.e. a state change due to a fault) having the same effect as

computation step (i.e. as step taken by the algorithm) does not count as fault

(step). This is indicated by the “F\A” subscript of the # function. The value of g

may also be interpreted as a percentage. The function r can be perceived as the

service’s loss or reduction of quality with r(i), 0 ≤ i ≤ f, upper-bounding the loss

due to the i-th fault. Note that an f - region-adherent system is able to tolerate at

least f faults and is still exhibiting a service quality higher than 0%. For example, a

reduction function r with r(i)=i - δ for i = 0, . . . , f with f = 3 and δ < 1/f describes

the non-masking fault-tolerance behavior of the example system of Fig. 2 and Fig.

3 as 3-region-adherent.

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Fig. 2. Worst Case and Particular Behavior of a Region-Adherent System over Time.

Fig. 3. Topological Interpretation of a Region-Adherent System.

3 Work Done so Far and Future Perspective

Examples of region-adherent systems have been presented in Becker et al. (2013,

2014a, 2014b) along with a formal definition of region-adherence and formal

techniques for proving the region-adherence property: We introduced the concept

of region-adherence and presented a wireless sensor network (WSN) for

monitoring the air humidity in some geographical region in Becker et al. (2013).

In this WSN, a region-adherent algorithm was used that helped to quantify the

effects of failed sensors in the sensing process of the WSN. A simple refinement

of the lower bounds of service quality known of a region-adherent system we

presented by Rahmatov and Theel (2015). In Becker et al. (2014a), we gave a

formal definition of region-adherence. A distributed Bubblesort algorithm we

presented in Becker et al. (2014b) that combines region-adherence and self-

stabilisation. Furthermore, we presented techniques that ease the formal

verification of region-adherence and gave a formal proof of the region-adherence

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property of the Bubblesort algorithm. Furthermore, we analysed the service quality

of the algorithm via simulation in the average case and compared it to the worst-

case behavior stated by the region-adherence property.

Similar to self-stabilising systems, the construction of region-adherent systems

is not an easy task and requires careful algorithm design. Thus, we are particularly

interested in the following topics: 1) the design of region-adherent systems: for

designing region-adherent systems, the challenge is to find out how to

systematically get/design a region-adherent algorithm; 2) methodologies of

formally verifying region-adherence of a system and analysing related

properties: in this case we have to find out what properties can be exploited such

that the verification becomes simple; 3) a systematic refinement of the lower

bounds of service quality known of a region-adherent system: here, we would

like to find out what observations of properties allow for a strengthening of the

lower bounds known for a system so far; 4) a systematic improvement of a

given region-adherent system with respect to region-adherence-related

properties, such as number of faults it tolerates prior to delivering a service

quality of 0%: in this case questions are what changes e.g. to the algorithm can be

done such that the region-adherent property is improved? if a sys- tem is proven to

be region-adherent for f faults, then how can underlying algorithm be altered such

that it becomes region-adherent for (n + 1)f faults? 5) the systematic composition

of one or more (region-adherent) systems such that the resulting system

is region-adherent by design, namely, without the need of subsequently

proving the region-adherence property explicitly: there, we hope to identify

composition techniques that the resulting system is region-adherent. This way, we

can construct a region-adherent system; 6) a systematic combination of region-

adherence and self-stabilisation, since such a combined system, on one side,

exhibits a region-adherent behaviour while being hit by faults. On the other side,

it recovers to full service quality in the course of time. In this combination, a

system can potentially exhibit a high level of “expected service quality” since it is

highly available due to self-stabilisation and still offers some (potentially high)

service quality even after some number of faults.

Acknowledgments The work is partially supported by the German Research Foundation in the

scope of DFG GRK 1765/1 SCARE, DFG SFB/TR AVACS 14/3 and the European

Commission’s Erasmus Mundus TARGET II program.

References

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Becker JS, Rahmatov D, Theel O (2014a) Brief Announcement: Region-Adherent Algorithms –

Bounding the Impact of Faults in Space. In: Proceedings of the 16th International Symposium

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Becker JS, Rahmatov D, Theel O (2014b) Region-Adherent Algorithms: Restricting the Impact

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Herlihy MP, Wing JM (1987) Specifying Graceful Degradation in Distributed Systems. In:

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