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Chapter 12

Chapter 12. Systems Development. Overview of Systems Development. Participants Initiating systems development Information systems planning Establishing objectives for systems development Systems development and the Internet Trends in systems development and enterprise resource planning.

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Chapter 12

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  1. Chapter 12 Systems Development

  2. Overview of Systems Development • Participants • Initiating systems development • Information systems planning • Establishing objectives for systems development • Systems development and the Internet • Trends in systems development and enterprise resource planning

  3. 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

  4. Managers System stakeholders Programmers Systems analyst Users Technicalspecialists Vendors and suppliers

  5. 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.

  6. Typical Reasons to Initiate a Systems Development Project Problems with existing systems Desire to exploit new opportunities Increasing competition Perception of potential benefit by individualcapable of initiatingchange Systems developmentprocess initiated Desire to make moreeffective use of information Organizational growth Merger or acquisition Change in market orexternal environment

  7. Planning • Information systems planning • The translation of strategic and organizational goals into systems development initiatives • Creative analysis • The investigation of new approaches to existing problems • Critical Analysis • The unbiased and careful questioning of whether system elements are related in the most effective or efficient ways Strategic plan IS planning Systems developmentinitiatives

  8. Steps in IS Planning Strategic plan Previously unplannedsystem projects Developing overall objectives Identify IS projects Set priorities & select projects Analyse resource requirements Set schedules and deadlines Develop IS planning document

  9. 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 application • Fixed investments in hardware and related equipment • On-going operating costs of the system

  10. Systems Developmentand 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

  11. It’s a“cycle” Systems Development Life Cycle • Systems investigation • Problems and opportunities are identified • Systems analysis • Existing systems and work processes are studied • Systems design • Defines how the information system will do what it must do to solve the problem • Systems implementation • System components are assembled and the new or modified system is placed into operation • Systems maintenance and review • Ensures the system operates and is modified to keep up with business changes

  12. Systems investigation(understand problem) Systems Analysis(understand solution) Systems design(select and plan best solution) Systems implementation(place solution into effect) Systems maintenanceand review(evaluate results of solution)

  13. Cost tomake a particularchange Investigation Analysis Design Implementation Maintenance and review Time

  14. Prototyping • Operational prototype • Accesses real data files, edits input data, makes necessary computations and comparisons, and produces real output • Non-operational prototype • A mockup or model that includes output and input specifications and formats • Rapid application development (RAD) • Employs tools, techniques, and methodologies designed to speed application development, automates source code generation, and facilitates user involvement in design and development activities • Joint application development (JAD) • Involves group meetings in which users, stakeholders, and IS professionals work together to analyze existing systems, proposed solutions, and define requirements for a new or modified system.

  15. 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, many traditional 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.

  16. Prototyping: The Iterative Life Cycle Iteration 1 Iteration 2 Iteration 3 (final) Determinerequirements Determinerequirements Determinerequirements Analysealternatives Analysealternatives Analysealternatives Specify design Specify design Specify design Implementdesign Implementdesign Implementdesign User review User review Changeover

  17. General Model of Prototyping Systems development initiated Investigate and analyse problemsufficiently to developworkable solution Develop prototype Put prototype into operation Refine and modify prototype Complete component or system

  18. 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

  19. Factors Affecting Systems Development Success • Managing change • Requires the ability to recognize existing or potential problems and deal with them before they become a serious threat to the success of a new or modified system • Use of project management tools • Schedule • Milestone • Deadline • Critical path • Program Evaluation Review Technique (PERT) • Gantt chart

  20. Selected Project Management Software Packages

  21. Use of Computer-Aided Software Engineering (CASE) Tools • CASE tools automate tasks required in a system development 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 later implementation 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 program code from upper-CASE package generated designs

  22. CASE • Short for Computer Aided 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.

  23. ISO 9000 • An international standard used by IS departments to ensure quality standards exist and are maintained in their products and services

  24. 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

  25. 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

  26. The Systems Investigation Report • A report that summarizes the results of the systems 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 IS department and other functional areas

  27. Systems Analysis • Typical table of contents from a systems investigations report: • Table of Contents • Executive summary • Review of goals and objectives • System problems and opportunities • Project feasibility • Project costs • Projects benefits • Recommendations

  28. 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

  29. Data Collection • Structured Interview • Unstructured Interview • Direct Observation • Questionnaires • Statistical Sampling Identify data sources Data collection Follow-up & clarification

  30. 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 organizational objects 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 diagram that models objects, associations, and activities by describing how data can flow between and around them

  31. ER Example MID 1 Play  Game of Golf Member Name Address Datepaid Date Time Score MID

  32. 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)

  33. Processsymbol Entity symbol Data-flow line Data-flow line Data store Assign Tee time Tee time Available times Member Schedule Reservation request Group information Membertee time Course access Checkmemberin Member Member card Member ID Date Sortscores Score card Score card Member Scores Calculatehandicap Handicap Tee time

  34. Application Flowchart • Charts that show relationships among applications or systems Order processingapplication Inventory controlapplication Invoicingapplication Marketing analysisapplication

  35. Grid Charts • A table that shows relationships among the various aspects of a systems development effort X X X X X X X X

  36. Requirements Analysis • An assessment used to determine user, stakeholder, and organizational needs Strategytranslation Goals and missionof the organization Systemsrequirements

  37. Screen Layout Charts • May be tailored for… • Frequent users who require little descriptive information, or • Infrequent users who require more descriptive information

  38. For frequent users…

  39. For infrequent users… 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

  40. The Systems Analysis Report • Strength and weaknesses of existing system from a stakeholder’s perspective • User/stakeholder requirements for the new system • Organizational requirements • Description of what new information systems should do to solve the problem

  41. Typical Table of Contents for a Report on an Existing System Johnson & Flores, Inc. Systems Analysis Report TABLE OF CONTENTS Background Information Problem or Need Statement Data Collection Data and Requirements Analysis Recommendations Appendixes of Documents, Tables, and Charts Glossary of Terms

  42. End of Chapter 12 Chapter 13

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