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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 - PowerPoint PPT Presentation
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System Analysis (Part 1)
What is a System?What is Analysis?System AnalysisWhy would we change a System?The System Development Life CycleProblem 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;
1. Our old system is outdated 2. Something could go wrong with
the current system3. 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.
Maintenance
Implementation
Design
Analysis
System Development Life Cycle 1) Project Selection and Feasibility Study2) Present System study and Analysis3) System Design of the New System 4) Programming and Documentation5) Implementation and Change Over6) System Control and Review7) System Maintenance
AnalysisThis is the over all study of the current system, looking at why we should change the system and if it is worth the change.
1. Project Selection and Feasibility Study
2. Present System Study and Analysis
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
1
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;
1. Money2. Time3. 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.
Present System Study and AnalysisThis 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
2
What goes on …The following main points are
analysed
1. How the employees work 2. Who is in charge of the different
departments3. How the employees feel about
the current system4. 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
1. Interviews2. Questionnaires3. Surveys 4. Observations5. 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
1. More work2. Training3. Technology 4. Job takeover 5. Less work ect …
Design General planning and building of
the new system3. System design of the new
system 4. Programming and
Documentation
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
3
The Four Design Tasks1. Setting what the new system should
output
2. Deciding what the system would need as an input to create the results
3. What files and fields the system needs to hold the data
4. Setting the processing of the system (insertions, deletion, editing ect…)
Programming and DocumentationThis third step is divided into two
parts
1. The programming part = actually creating the program itself
2. Documentation = creating a booklet containing all the information needed about the system
3
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 1. technical documentation2. user documentation 3. program documentation (explained later on)