Upload
dr-singh
View
232
Download
0
Embed Size (px)
Citation preview
8/3/2019 Systems Development - MIS
1/42
Prof. Rushen Chahal
Systems Development
8/3/2019 Systems Development - MIS
2/42
Overview of Systems
Development Participants Initiating systems development
Information systems plann
ing
Establishing objectives for systemsdevelopment
Systems development and the Internet
Trends in systems development andenterprise resource planning
8/3/2019 Systems Development - MIS
3/42
Participants
Stakeholders Individuals/organizations who are beneficiaries of the
systems development effort
Systems analyst Professional who specializes in analyzing and
designing business systems
Users Individuals who interact with the system regularly
Programmer Individual responsible for modifying or developing
programs to satisfy user requirements
8/3/2019 Systems Development - MIS
4/42
Systems analyst
Managers
Vendors and suppliers
System stakeholders
Users Technical
specialists
Programmers
8/3/2019 Systems Development - MIS
5/42
Systems Analyst
A programmer or consultant who designs and manages the
development of business applications. Typically, systems
analysts are more involved in design issues than in day-to-day
coding. However, systems analyst is a somewhat arbitrary title,so different companies define the role differently.
8/3/2019 Systems Development - MIS
6/42
Typical Reasons to Initiate a
Systems Development Project
Desire to make more
effective use of information
Problems with existing systems
Desire to exploit new opportunities
Increasing competition
Organizational growth
Merger or acquisition
Change in market or
external environment
Perception of potential
benefit by individual
capable of initiating
change
Systems development
process initiated
8/3/2019 Systems Development - MIS
7/42
Planning
Information systems planning
The translation of strategicand organizational goals intosystems developmentinitiatives
Creative analysis
The investigation of newapproaches to existingproblems
Critic
al Analysis The unb iased and careful
questioning of whethersystem elements are relatedin the most effective orefficient ways
Strategic plan
IS planning
Systems development
initiatives
8/3/2019 Systems Development - MIS
8/42
Steps in IS Planning
Strategic plan
Developing overall objectives
Identify IS projects
Set priorities & select projects
Analyse resource requirements
Set schedules and deadlines
Develop IS planning document
Previously unplanned
system projects
8/3/2019 Systems Development - MIS
9/42
Establishing Objectives for
Systems Development Performance objectives Quality or usefulness of the output
The quality or usefulness of the format of the output
The speed at which the output is generated Cost objectives
Development costs
Costs related to the uniqueness of the system
applic
ation
Fixed investments in hardware and related equipment
On-going operating costs of the system
8/3/2019 Systems Development - MIS
10/42
Systems Development
and the Internet Applications being moved to the Internet Sales
Order placement
Product information access
Building a static Web site
Intranet tools NetDynamics
SilverStream
Web-Logic Novera
Netscape Communications
8/3/2019 Systems Development - MIS
11/42
Systems Development Life
Cycle Systems investigation
Problems and opportunities are identified
Systems analysis
Existing systems and work processes are studied Systems design
Def ines how the information system will do what it must doto solve the problem
Systems implementation
System components are assembled and the new ormodified system is placed into operation
Systems maintenance and review Ensures the system operates and is modified to keep up
with business changes
Its a
cycle
8/3/2019 Systems Development - MIS
12/42
Systems maintenanceand review
(evaluate results of solution)
Systems implementation
(place solution into effect)
Systems design
(select and plan best solution)
SystemsAnalysis
(understand solution)
Systems investigation
(understand problem)
8/3/2019 Systems Development - MIS
13/42
Cost to
make aparticular
change
Investigation Analysis Design Implementation Maintenance
and reviewTime
8/3/2019 Systems Development - MIS
14/42
Prototyping
Operational prototype
Accesses real data files, edits input data, makes necessarycomputations and comparisons, and produces real output
Non-operational prototype
A mo ckup or model that includes output and input specifications andformats
Rapid application development (RAD)
Employs tools, techniques, and methodologies designed to speedapplication development, automates source code generation, andfacilitates userinvolvement in design and development activities
Joint appl
ication de
velopment (JAD) Involves group meetings in which users, stakeholders, and IS
professionals work together to analyze existing systems, proposedsolutions, and define requirements for a new or modified system.
8/3/2019 Systems Development - MIS
15/42
Rapid Application Development
A programming system that enables programmers to quickly
build working programs. In general, RAD systems provide a
number of tools to help build graphical user interfaces that
would normally take a large development effort. Two of the most
popular RAD systems for Windows are Visual Basic and Delphi.
Historically, RAD systems have tended to emphasize reducing
development time, sometimes at the expense of generating
efficient executable code. Nowadays, though, many RAD
systems produce extremely fast code. Conversely, manytraditional programming environments now come with a number
of visual tools to aid development. Therefore, the line between
RAD systems and other development environments has become
blurred.
8/3/2019 Systems Development - MIS
16/42
Prototyping:
The Iterative Life CycleDetermine
requirements
Analysealternatives
Specify
design
Implementdesign
User review
Iteration 1
Determine
requirements
Analysealternatives
Specify
design
Implementdesign
User review
Iteration 2
Determine
requirements
Analysealternatives
Specify
design
Implementdesign
Changeover
Iteration 3 (final)
8/3/2019 Systems Development - MIS
17/42
General Model of Prototyping
Systems development initiated
Investigate and analyse problem
sufficiently to develop
workable solution
Develop prototype
Put prototype into operation
Refine and modify prototype
Complete component or system
8/3/2019 Systems Development - MIS
18/42
End-User Systems
Development Life Cycle End-user systems development life cycle Any systems development project in which
the primary effort is undertaken by a
combination of business managers and users
8/3/2019 Systems Development - MIS
19/42
Factors Affecting Systems
Development Success Managing change
Requires the ability to recognize existing or potentialproblems and deal with them before they become a
serious threat to the su
ccess of a new or mod
ifiedsystem
Use of project management tools Schedule
Milestone
Deadline Cr itical path
Program Evaluation Review Technique (PERT)
Gantt chart
8/3/2019 Systems Development - MIS
20/42
8/3/2019 Systems Development - MIS
21/42
Selected Project Management
Software PackagesSoftware Vendor
BeachBox 98 NetSQL Partners
Job Order Management Software Inc.
OpenPlan Welcom
Project Microsoft
Project Scheduler Scitor Corp.
Super Project Computer Associates
8/3/2019 Systems Development - MIS
22/42
Use of Computer-Aided
Software Engineering (CASE)Tools
CASE tools automate tasks required in a systemdevelopment effort and enforces adherence to the SDLC
Upper CASE tools Tools that focus on activities associated with the early stages of
systems development
Lower CASE tools Tools that focus on the laterimplementation stage of systems
development
Integrated-CASE (I-CASE) tools Tools that provide links between upper- and lower-CASE
packages, allowing lower-CASE packages to generate programcode from upper-CASE package generated designs
8/3/2019 Systems Development - MIS
23/42
CASE
Short for ComputerAided Software Engineering, a category of software that provides a
development environment for programming teams. CASE systems offer tools to
automate, manage and simplify the development process. These can include tools for:
Summarizing initial requirements
Developing flow diagrams
Scheduling development tasks
Preparing documentation
Controlling software versions Developing program code
Various companies offer CASE software capable of supporting some or all of these
activities. While many CASE systems provide special support for object-oriented
programming, the term CASE can apply to any type of software evelopment
environment.
8/3/2019 Systems Development - MIS
24/42
ISO 9000
An international standard used by IS
departments to ensure quality standards
exist and are maintained in their products
and services
8/3/2019 Systems Development - MIS
25/42
Systems Investigation
Identify potential problems and opportunities and
consider them in light of the goals of the company
The investigation team
Managers and stakeholders IS personnel
Task
Undertake feasibility analysis
Establish system development goals
Select system development methodology
Prepare system development report
8/3/2019 Systems Development - MIS
26/42
Feasibility Analysis
Technical feasibility Can the hardware, software, and other system components be
acquired or developed to solve the problem?
Operational feasibility
Can the project be put into action or operation?
Schedule feasibility Can the project be completed in a reasonable amount of time?
Economic feasibility Does the project make financial sense?
Net present value The preferred approach for ranking competing projects and
determining economic feasibility
8/3/2019 Systems Development - MIS
27/42
The Systems Investigation
Report A report that summarizes the results of thesystems investigation and the process of
feasibility analysis and recommends a
course of action
Steering committee
An advisory group consisting of senior
management and users from the ISdepartment and other functional areas
8/3/2019 Systems Development - MIS
28/42
Systems Analysis
Typical table ofcontents from a systems
investigations report:
Table of Contents
1. Executive summary
2. Review of goals and objectives
3. System problems and opportunities
4. Project feasibility
5. Project costs
6. Projects benefits
7. Recommendations
8/3/2019 Systems Development - MIS
29/42
Sources of Data
Internal Sources
Users, stakeholders, managers
Organization charts
Forms and documents
Procedure manuals and policies
Financial reports
IS manuals
Other measures of business
processes
External Sources
Customers
Suppliers
Stockholders
Government agencies
Competitors
Outside groups Journals, etc.
Consultants
8/3/2019 Systems Development - MIS
30/42
Data Collection
Structured Interview
Unstructured Interview
Direct Observation
Questionnaires
Statistical Sampling
Identify data sources
Data collection
Follow-up & clarification
8/3/2019 Systems Development - MIS
31/42
Data Analysis
Data analysis Manipulating collected data so that it is usable for the
development team members participating in systems analysis
Data modeling
A commonly accepted approach to modeling organizationalobjects and associations that employ both text and graphics
E.g, ER (entity relationship) diagrams
Activity modeling A method to describe related objects, associations, and activities
Data flow diagram A d iagram that models objects, associations, and activities by
describing how data can flow between and around them
8/3/2019 Systems Development - MIS
32/42
ER Example
PlayMember Game of Golf
MID
Name Address
Date
paid Date Time Score
1 g
MID
8/3/2019 Systems Development - MIS
33/42
Data Flow Diagram
Schematic description of business
processes
Premise: for every activity there is some
communication, transference, for flow that can
be described as a data element
DFDs show logical sequences (not physical
processes)
8/3/2019 Systems Development - MIS
34/42
Entity symbol Data-flow lineProcess
symbolData-flow line Data store
Member
Member
Member
Assign
Tee time
Checkmember
in
Sortscores
Calculatehandicap
Schedule
Member card
Scores
Tee time
Reservation request
Course access
Member ID
Score card
Handicap
Available times
Group information
Member
tee time
Date
Score card
Tee time
8/3/2019 Systems Development - MIS
35/42
Application Flowchart
Charts that show relationships among
applications or systems
Order processing
application
Inventory control
application
Invoicing
application
Marketing analysis
application
8/3/2019 Systems Development - MIS
36/42
Grid Charts
A table that shows relationships among the
various aspects of a systems development
effortDatabaseapplications
Customer
database
Inventory
database
Supplier
database
Accounts receivable
database
Order processing
applications
Inventory control
application
Marketing analysis
application
Invoicing
application
X X
X X
X X
X
X
8/3/2019 Systems Development - MIS
37/42
8/3/2019 Systems Development - MIS
38/42
Screen Layout Charts
May be tailored for
Frequent users who require little descriptive
information, or
Infrequent users who require more descriptive
information
8/3/2019 Systems Development - MIS
39/42
ITEM NO. QTY UNIT PRICE DOLLARS DISCOUNTSXXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
ORDER ENTRY
ORDER
NO.
CUSTOMER
NO.
SALES
PERSON REGION COMMISSION
NET
DOLLARS
XXXXX XXXXX XXXXX XXX XXX XXXXX
For frequent users
8/3/2019 Systems Development - MIS
40/42
Which online option would you like to perform?(Please enter an X to make a selection)
_DATA ENTRY Enter transaction and report
requests for later processing
_RETRIEVALS Review online information from the
database: bill of materials,
where-used, routing, item data
For infrequent users
8/3/2019 Systems Development - MIS
41/42
The Systems Analysis Report
Strength and weaknesses of existing
system from a stakeholders perspective
User/stakeholder requirements for the newsystem
Organizational requirements
Desc
ri
pti
on of what newi
nformati
onsystems should do to solve the problem
8/3/2019 Systems Development - MIS
42/42
Typical Table of Contents for
a Report on an ExistingSystem
Johnson & Flores, Inc.
Systems Analysis Report
TABLE OF CONTENTS
Background Information
Problem or Need Statement
Data Collection
Data and Requirements AnalysisRecommendations
Appendixes of Documents, Tables, and Charts
Glossary of Terms