INTRODUCTION
1. Concepts
System Analysis and Design in this unit (SAD) is the application of the system approach to the study and solution of problem using computer-based systems
Systems approach is a way of thinking about the analysis and design of a computer –based application. It provides a framework of visualizing the organizational and environmental factors that operate on a system.
Organizations are complex systems that consist of interrelated and interlocking sub-systems.
Systems analysis and design focuses on; - Systems - Processes - Technology
What is a system?
The term system is derived from a Greek word Systema meaning an organized relationship among functioning units or components.
OR;
A system is an orderly grouping of interdependent components linked together according to a plan to achieve a specific objective.
A Component may refer to: Physical parts e.g.; engines, wings of air craft, wheels of a car etc; Managerial steps (planning, organizing, directing and controlling);A sub-system in a multi-level structure.
A system exists because it is designed to achieve one or more objectives.
Examples of systems: Transpiration system, Telephone system, Computer system e.t.c
2. Characteristics of a system 1. Organization (order) 2. Interaction 3. Interdependence 4. Integration 5. A central objective
Organization: This implies structure and order. It is the organization of components that help to achieve the objectives. For example: A computer system is designed around as input device, a Central Processing Unit, an Output Device and a Storage Device. When linked together they work as a whole system for producing information. Fig. 1.1
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Fig. 1.1: Organization Structure
Interactions: Refers to the manner in which each component functions with other components of the system. Example: In computer system, the CPU must interact with Input Device to solve a problem. In turn, the Main Memory holds programs and data that the
Bibliography: Adapting the procedure presented by Awad (1997), the determination of costs and benefits entails the following steps: i