Detailed Design

Introduction

• The design translates the system requirements into ways of operate them.

• The design is a solution, a “ how to “ approach, compared to analysis, a “what is” orientation.

• The design phase focuses on the detailed implementation of the system recommended in the feasibility study.

Modularization

• One way to plan a new system is to focus on each functional subsystem as a separate entity or application area.

• Using such an approach, each application area is treated as if it were totally independent.

• The modular systems approach divides each application area into a number of smaller units called modules.

Advantages Of Modularization• speed up the systems process.

• eliminates unnecessary duplication.

• result in higher quality.

• provides better control over the total system project.

• allows flexibility as additional features may be added later.

• parts of the system can be tested separately.

limitations Of Modularization

• Modular systems design is best viewed as one aspect of a broader planning issue, but it is not a required step in the design process.

• changes and errors affect common modules, the negative consequences can be widespread

Input Design

• Inaccurate input data are the most common cause of error in data processing.

• Errors entered by operator can be controlled by input design.

• Input design is the process of converting user-originated inputs to a computer based format.

Goal of input design

• The goal of designing input data is to make data entry:-

• Easy

• Logical

• Error free.

Input media and devices

• Keyboard

• Mouse

• Touch Screen

• Sound and speech

• Automatic data capture• Optical mark recognition (OMR)

• Bar codes

• Optical character recognition (OCR)

• Magnetic Ink

Data input methods

• ON-LINE - User directly Enters data using screen prompts.

• OFF-LINE -Forms filled by users- for example-candidates for admission to a college fill forms

DATA OUTPUT DESIGN

• Outputs present information to system users.

• Outputs, the most visible component of aworking information system, are thejustification for the system.

• During systems analysis, you defined outputneeds and requirements, but you didn'tdesign those outputs.

Output-design Objectives

• Serve the intended purpose

• Deliver the right quantity of output

• Deliver it to the right place

• Provide output on time

Outputs Reports

• Detailed Reports: • Present information with little or no filtering or

restrictions. • Some detailed reports are historical in nature.

• Exception Reports: • Filter data before it is presented to the manager

as information.• Exception reports only report exceptions to some

condition or standard.

Types of Outputs

• Internal outputs

It stay inside the system to support the system's users and managers

• External outputs

It leave the system to trigger actions on the part of their recipients or confirm actions to their recipients

Output Media

• Paper

• Screen

• Microfilm

• Video/Audio

• CDROM, DVD

• Other electronic media

Output Formats

• Tabular output

• Zoned output

• Graphic output

• Narrative output