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System Analysis (Part 1). What is a System? What is Analysis? System Analysis Why would we change a System? The System Development Life Cycle Problem Selection and Feasibility Study. What is a System?. A system is a group of components working together to reach a specific goal
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System Analysis (Part 1) What is a System? What is Analysis? System Analysis Why would we change a System? The System Development Life Cycle Problem Selection and Feasibility Study
What is a System? • A system is a group of components working together to reach a specific goal • If one of the components are missing the system would not work the way it should • For example a car is a system made up of the body, wheels, steering wheel and an engine, if the car had no wheels it would be useless
What is Analysis? • Analysis is the process of studying something very closely • To analysis something we would look at ALL the different components of the system and how they work together • Analysis is like being a detective and studying EVERYTHING about the system
System Analysis • As the name suggests this is the processes of analysing a system very closely • System analysis is normally used when a company wishes to change their current system • A team of people would all work together to analysis the current system and come up with a better one
Why Change a System? • We change a system for many different reasons, some being; • Our old system is outdated • Something could go wrong with the current system • The company could grow and need a better system
Why do we need System Analysis? • The software we have on our home computers is very different to that used on company computers • The software is more complex hence problems that may arise are much bigger, hence it would be too difficult for one person to manage alone, we would need team of people • In order to create and maintain a software for a company there would need to be a formal plan
… • For this formal plan to take place the team hired by the company would have to go through a number of System Analysis steps • System analysis is essential, to plan the software and to enable members of the team to communicate during development and also afterwards.
System Development Life Cycle • Project Selection and Feasibility Study • Present System study and Analysis • System Design of the New System • Programming and Documentation • Implementation and Change Over • System Control and Review • System Maintenance Analysis Design Implementation Maintenance
Analysis This is the over all study of the current system, looking at why we should change the system and if it is worth the change. Project Selection and Feasibility Study Present System Study and Analysis
1 Project Selection and Feasibility Study • This is the very first step of System Analysis • This is the fist study of the system where the team decide if a solution is possible and how it may be done • At this stage the company would find out how long the change over would take and how much it would cost and so on
The Feasibility Study • This study is where the team lets the company know if it is worth them to change their system • The company would need to think of things such as; • Money • Time • Training of staff ect…
The Results of this Stage • Describes the context of the problem. • Contains an evaluation, or simple analysis, of the problem. • Identifies, and justifies, ways in which the problem may be solvable. • Involves a cost-benefit analysis to decide if a solution is affordable.
2 Present System Study and Analysis • This stage of analysis is the study of the system that is currently in place • At this stage the WHOLE system is studied leaving out nothing • Even the people involved in the system such as the employees are studied
What goes on … • The following main points are analysed • How the employees work • Who is in charge of the different departments • How the employees feel about the current system • What the employees thing about change
How its done… • This stage of analysing the current system involves a lot of work • In order to carry out the investigations the team would use • Interviews • Questionnaires • Surveys • Observations • Group meetings ect …
Resistance to Change • In the stage of analysis the team would find out what the employees thing about the change • Some employees might not be keen on things being changed this could be due to • More work • Training • Technology • Job takeover • Less work ect …
Design General planning and building of the new system 3. System design of the new system 4. Programming and Documentation
3 System Design • This stage is a very long time consuming stage. • At this time the actual designing of the program is done • This is when the planning of the program is done using pseudo code, flow charts, mock ups and so on
The Four Design Tasks • Setting what the new system should output • Deciding what the system would need as an input to create the results • What files and fields the system needs to hold the data • Setting the processing of the system (insertions, deletion, editing ect…)
3 Programming and Documentation • This third step is divided into two parts • The programming part = actually creating the program itself • Documentation = creating a booklet containing all the information needed about the system
Programming • The team would have trained programmers who would spend a lot of time actually creating the system • The programmers would use the design material created in the previous stage
Documentation • Documentation is a very important part of creating a new program • Documentation is written information and diagrams which helps users use the system better and it enables maintenance • Documentation consists • technical documentation • user documentation • program documentation (explained later on)