What is a System

1.2. What is a System?

A system is a collection of components witch work together to achieve a specific goal. These components are connected to maintain communication when the work together. However, they have independent functionalities. Therefore,    each component is another system, named as subsystem, which carries out task to achieve some objectives of the original system.

1.2.1. What is the System components and Concepts

• System boundary : separate the system from its environment and define what is inside and what is outside the system
• System Environment : External world that the system usually interacts with System
• System Configuration : The way system elements organized or arranged in the system

1.2.2. What are the System type and there characteristics

System	Description	Example
Simple Vs. Complex	Few components with simple relationship or inter connection between elements	A pen
	Many element that are highly related and interconnected	Human Body
Stable vs. Dynamic	Undergoes very little change over time	Vehicle
	Undergoes rapid and constant change over time	Human body
Permanent Vs. temporary	Will exist for a long period of time	School
	Will exists for short period of time	Decoration
Open Vs. closed	Interacts with environments	Human body
	No interaction with environment	Prison
Adaptive Vs. Non Adaptive	Able to change in response to change in the environment	Human body
	Do not able to change response to changes in the environment	House

Note – a single system can belong to many different system types based on their characteristics

1.2.3. What is the System Performance and standards

Any system should work properly. This can be identified by evaluating its performance. Ones standard established, system performance is measured and compared with the standard. Variances from the standard can determine the system actual performance. System performances can be measured using efficiency and effectiveness.

Efficiency	Effectiveness
A measure of what is produced divided by what is consumed	A measure of the extent to which a system achieves its goals
A relative term used to compare system	A relative term used to compare system
Can range from 0 to 100 percent	Can be computed as what goals are achieved from the total stated goals

1.2.4. What are the System variables and parameters

System variables	System Parameters
A quantity or item that can be controlled by the decision maker	A value of quantity that cannot be controlled by the decision makers
Eg : Student Course fee	Eg : Student VAT charge percentage

1.2.5. What are the System Modeling 

Things in real world are complex and dynamic and difficult to understand. Therefore we can use models to simplify and understand real world system much easily. A model is an abstraction on or an approximation that is used to represent reality.

Narrative Model	A logical model based on words. Both variable and written descriptions of reality are considered as narrative models.  Eg : reports, documents
Physical Models	A physical or tangible represent of reality. Many physical models are computer designed or constructed Eg : A model of car
Schematic model	A Logical model witches graphically represent reality. Eg : Graphic, chart, Figure, diagrams, illustrations, and pictures.
Mathematical model	An arithmetic representation of reality. Computers excel at solving mathematical models. Eg : Budget

   
In developing any model. accuracy is critical and models should be realistic as much as possible. user must be aware of the assumptions under witch the model was developed.