design strategiesfor example – sunrise systemsdesign specificationsproject deliverable: the preliminary presentationform design fundamentalsthe cornucopia caseportfolio project

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Chapter Objectives

When you complete this chapter you will be able to:• Transform the project objectives into a

preliminary design model that the user can follow and understand

• Explain why the focus of design work begins with the user’s perspective and ends with the hardware perspective

• Adapt a joint application design (JAD) methodology to fit a small-enterprise systems project

• Design a set of user-friendly screen forms

2

Design Strategies

• The user is an important part of any design strategy

• Design is a circular process, with repeated evaluation and revision

• User satisfaction, as well as cost and due-date constraints often dictate when the analyst can conclude the design phase

3

Figure 7-1: Modeling Chronology

4

Figure 7-2: User-Driven Design

5Chapter 7

Figure 7-3: Information System Stages

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Business Transformation System Stages

7Source: Cap Gemini Ernst & Young

Traditional Information System Types

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•Transaction processing system•Online transaction processing (OLTP) system•Batch processing system•Management information system (MIS)•Decision support system (DSS)•Local area networked (LAN) information system•Wide area networked (WAN) information system•Expert systems information networks•Strategic information systems

TECHNOTE 7-1

9

Figure 7-4: Small-Enterprise Design Choices

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Figure 7-5: Problem-Solving Strategies

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Modular Design: Coupling and Cohesion

Formal Joint Application Design

12

•An alternative to traditional analyst-centric systems analysis and design

•With JAD, both the analyst and the user engage in the problem-solving process through intense workshops in which all participants are expected to contribute to the solution

TECHNOTE 7-2

13

Design Evaluation Criteria

1. End-user orientation2. Understandability3. Expandability4. Security5. Execution Speed6. Expense to Develop7. Time to Develop8. Accessibility

Design Specifications

• Design specifications provide– the user with the first detailed look at the system– the analyst with the blueprint from which the

system will be built• A design prototype includes sample screen

forms, source documents, and reports

14

Form Design Fundamentals

• Forms can be used as input or output documents

• Forms can be electronic (screen forms or softcopy) or paper (hardcopy)

• The electronic form has become the principal input document (source document) for many information systems

• User-friendly screen forms employ many of the familiar Windows features to enhance readability and reduce user data entry errors

15

Web Page Design

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The Internet presents several design challenges

Transmission speedClient-side computingConstruction tool setsCompetitionContent currencyNavigational strategy

TECHNOTE 7-4

Graphical User Interface Dialogs (GUIDs)

• Windows based applications use GUI dialog sequences to help users select and tailor commands or service requests

• GUID is the term used to define a sequence of screen forms designed to provide a highly effective user-system feedback cycle within an enterprise information system

17

As the analysts embark on the design activities of this project, their first task is to develop a preliminary view of the new system design. The project contract and analysis phase activities present a fairly clear picture of what the new system must provide.

18

THE CORNUCOPIA CASE

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Cornucopia New System Requirements

Areas for improvement:• Customer record keeping• Product reordering• Customer communications• Sales trend analysis

Ideas for the new design:• Incorporate a sales subsystem• Associate suppliers with products• Associate customers with sales transactions• Provide Internet access

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Cornucopia New Subsystems

1. Sales (sales transaction capture)2. Sales trends (sales summarization)3. Reordering (CD orders based on sales)4. Customer (Customer master file)5. CD (CD master file)6. Supplier (Supplier master file)7. Correspondence8. Internet

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Cornucopia Form Design

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Cornucopia Preliminary Presentation Slide Show

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Cornucopia Billable Hours Form

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Cornucopia with Dreamweaver

Enlarge

Library Information System

The University library system will record the books owned by the library as well as any new books purchased and put into circulation. Before someone can borrow a book, he or she must show a valid ID card that is checked – to ensure that it is still valid – against the student files maintained by the registrar’s office (for student borrowers), the faculty/staff files maintained by the personnel office (for faculty/staff borrowers), or the library’s own guest file (for individuals issued a guest card by the library). The system must also check to ensure the borrower does not have any overdue books or unpaid fines before he or she can borrow another book. If no fines or overdue books are found, the book is checked out. The system should record who has borrowed what book and when it is due back. The borrower is also told the due date. Books can only be checked out for two weeks. When a book is overdue, the information about the book and the person who checked it out is added to an overdue file. Every Monday, the library prints and mails postcards to those people with overdue books. If a book is overdue by more than one month, a fine will be imposed and a librarian will telephone the borrower to remind him or her to return the book.

Library Information System

Create a Context diagram depicting the Library system and the other systems in interacts with.

Create a level 1 decomposition of the library system and show the files and processes required to make the system function.

Both diagrams should be created with VISIO or MsWord adhering to the standard DFD diagramming notation

Due Nov 1st

Chapter Summary

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• Information system design unfolds as a series of model building activities

• The design process includes the user• As a starting point, it is useful to consider

some of the common design options available for small-enterprise systems

• Electronic screen forms are a key component to system design

• The preliminary presentation provides a preview of the design