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Systems Development and Project Management

Introduction to the Systems Approach

 It’s methodology for problem solving

 The more time spent planning, the better the outcome

 Note the process is typically iterative

 Systems approach masters  Ed Yourdon  Grady Booch  The GOF  Gamma, Helm, Johnson, Vlissides

The Systems Approach

(Problem Identification)

 An existing system does not meet a

need or expectation

 Conduct feasibility studies

 If a project seems feasible, assemble a project management plan and team

The Systems Approach

(Feasibility Domains)

 Organizational  Do we have the human resources  Do we have the organizational resources

 Technical  Does the hardware / software exist

 Economic  Cost / benefit analysis  Accounting ROI  Present value analysis

 Operational

The Systems Approach

(Systems Analysis)

 Develop a list of functional

requirements

 User interface requirements  Processing requirements  Storage  Controls  Input validation  Event notification  Human controls

The Systems Approach

(Systems Design)

 We need to completely understand

the existing system

 If it’s not broke, don’t fix it  Understand how users use the existing system  Interviews  Know what users want out of the new system  At times, users don’t know what they want

The Systems Approach

(Systems Design)

 Process design

 Tools

 Flowcharts  IP charts  UML use-case diagrams  UML activity diagrams  UML Statechart diagrams

The Systems Approach

(Systems Design)

 Physical design

 Select physical hardware and software  Note that there may be site preparation requirements

End User Development

 Positives  Users get what they want

 Negatives  Users don’t know what they want  Users may have a narrow minded vision of the system  They may not see how a system contributes to the organizational mission  Loss of centralized control  Users are not experienced in system design methodologies

Testing

 My rule is, you cannot ever test too

much or be too thorough

 http://video.google.com/videoplay?

docid=2889527841583480458&q=p

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The Systems Approach (Maintenance)

 Perform a postimplementation audit

to determine whether goals were

met

 Revise system as necessary

Development Methodologies (1)

 Waterfall

 The systems lifecycle operates as a sequence of states  Sequential development

Development Methodologies (3)

 Extreme programming

 It’s an agile methodology at its best  Relies on close communication between users and developers  Relies on experienced developers  Uses small incremental deliverables

Development Methodologies (4)

 Scrum delivers small software

pieces every 30 days

 The term derives from the game of rugby  The development effort is monitored and controlled daily

 Some organizations use a

combination of these methodologies