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Public Management Information Systems System Analysis & Design Saturday, November 8, 2014. Hun Myoung Park, Ph.D. Public Management & Policy Analysis Program Graduate School of International Relations. System Development Life Cycle. I nvestigation (planning) Systems analysis Systems design
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Public Management Information SystemsSystem Analysis & DesignSaturday, November 8, 2014 Hun Myoung Park, Ph.D. Public Management & Policy Analysis ProgramGraduate School of International Relations
System Development Life Cycle • Investigation (planning) • Systems analysis • Systems design • System development • Systems implementation • System maintenance
Why SDLC? • Systematic approach to give guidelines for improving efficiency and effectiveness • To avoid system failures: lack of communication (acceptance); politics (sunk costs) and leaderships; technical incompetence; education & training • Considered as conceptual model and depending on institutional settings.
Caution in SDLC • Programming is a part of system development • Phases (steps) may not always be distinct and thus may overlap; Phases are interrelated and interdependence • Detecting errors in an early phase will save the cost
Prototyping • Iterative approach to revise prototypes. • “During each iteration, requirements and alternative solutions to the problem are identified and analyze, new solutions are designed, …” (p. 507) • “[A]n iterative process involving analysts and users whereby a rudimentary version of an information system is built and rebuilt according to user feedback.” (p.195)
Other Approaches • Rapid application development (RAD) • Agile (usage-centered) development • Extreme programming (XP) • Adaptive software development, lean software development, rational unified process, feature-driven development • Customization, fast cycles, error-correction
Step 1. Investigation • Determine organization’s objectives • Business process reengineering (BPR) • Feasibility analysis (economic, legal, operational, schedule feasibility) • Describing (tangible and intangible) costs and benefits of each solutions • Propose alternative solutions (keep or revise old system, or get a new system)
Step 2. System Analysis 1 • Data collection to gather data for information needs, resources, and capabilities • Data analysis for data modeling and activity modeling • Requirement analysis is to “determine user, stakeholder, and organizational needs” (p526).
Step 2. System Analysis 2 • Determine the nature and scope of the project. • Sources of data • Observations of users (conversations) • Written documents • Computer-based information
Step 2. System Analysis 3 • Traditional Data Collection • Interviews (individuals and groups) • Observing users • Questionnaires • Reviewing documents
Step 2. System Analysis 4 • Joint application development (JAD) • A highly organized intensive workshop to bring together system owners (managers), users, and technicians (e.g., analysts, programmers, engineers) to jointly define and design systems • “[A]nalysts control the sequence of questions answered by users” (p.192)
Step 2. System Analysis 5 • Computer-aided software engineering (CASE) tools • Data flow diagram (DFD), • System flowcharts (flow diagram) • Connectivity diagrams, grid charts, decision tables, • Object-oriented analysis
Step 2. System Analysis 6 • Business process reengineering (BPR) • “[L]ooking for new ways to perform current tasks” rather than “automating existing processes” (p.197). • “[N]ot just to improve each business process, but, … to reorganize the complete flow of data … to eliminate unnecessary steps, achieve synergies among … separate steps…” (p.197).
Step 2. System Analysis 7 • Key business processes are “structured set of measurable activities designed to produce a specific output for a particular customer or market” (p.198). • Is an activity dysfunctional? Important? Feasible? • Employ disruptive technologies that “enable the breaking of long-held business rules that inhibit …” (p.199).
Data Flow Diagram 1 • A picture of the movement of data between external entities and the processes and data stores within a system • Data flow (arrow) • Process (work or actions) • Data store in rectangular • Source/sink
Data Flow Diagram 2 • Context diagram or level-0 diagram • Overview of an organizational system that shows the system boundaries, external entities that interact with the system, and the major information flows between the entities and the system • Level-n diagram is a data flow diagram that is n nested decompositions from a process on a level-0
Data Flow Diagram 3 • Data flow allows only one direction • Data flow from and to data store means retrieving and updating information • Process (verb) has to have input and output • Data store must be moved by a process • Source/sink
Step 3. System Design 1 • Logical and functional designs • Defines input/output requirements (forms and reports) • Design user interfaces and dialogues • Design database/storage (data dictionary) • SpecifiesH/W, S/W, and networking (telecommunication)
Step 3. System Design 2 • System controls (I/O, process, database, telecommunication personnel control) • Rules and procedure (security, privacy, data integrity, and backups--recovery). • Described in request for proposal (RFP) specifying required resources (H/W, S/W)
Highlights • Iteration, but not a one-shot game • Not a technicians’ job but all stakeholders’ jobs to improve their performances • User centered approach; keep analyzing users needs all the time • Emphasis on reliability, security, privacy especially for contracting out projects • Importance of documentation in all stages.