1. Accounting Information System

2. System A system is a set of parts coordinated to accomplish a set of goals. It is also an organized set of interrelated ideas or principles forming a complex whole in an organization.

3. CLOSED SYSTEMS It is a system that is totally isolated from its environment, meaning it has no effects outside its boundaries, and the environment has no effect on the processes of the system.

4. . A closed system has an impermeable boundary that is strictly controlled or even restricts the acceptance or dispensing of data. It is a system which maintains itself on a limited amount of resources that are firmly established in that particular system hence being difficult to change it.

5. This system conceives of the organization as a system of management, technology, personnel, equipment and materials but tend to exclude competitors, suppliers, distributors and governmental regulators. This approach allows managers and organizational theorists to analyses problems by examining the internal structure of business with little consideration of external environment

6. Characteristics of closed systems It has no interfaces It has got strict impermeable boundaries which are also rigid There is no interaction with the environment Views organizations as relatively independent of environmental influences

7. Benefits of system There are no disturbances in the system Its highly effective and efficient

8. Limitations It is not practical in its nature

9. Examples A watch in that the battery is the only input used to produce output, time without any other form of input coming from other sources. Robot..

10. RELATIVELY CLOSED SYSTEMS These are systems which interact with the environment in a known and controlled way. Inputs from the environment that are used in the system are closely monitored so as to avoid disturbances in the processes of the system.

11. Predefined inputs outputs Unknown inputs System

12. Characteristics It does not eliminate susceptibility to the environment It contains interfaces There are adequate control measures in the system It allows for a reasonable level of sharing and exchange of information

13. Permeable boundary permeable boundary environment System 1 Interface System 2

14. Benefits of system It is well designed as it is able to both interact with its environment and the same time be able to control inputs to ensure safety It is able to meet user needs as they are able to take inputs for development purposes It minimizes the impact of disturbances as there are control measures E.g. pastel

15. OPEN SYSTEMS These are systems that continuously interact with their environment but the Interaction is not controlled. It takes place in the form of information, energy, material transfer into and out of the system boundary, depending on the discipline which defines the concept. Product subsystems convert inputs into marketable outputs with the goal of aiding the company adaptation to external conditions in its environment.

16. An open system is also a region of space characterized by a collection of components or elements related in some way, specializing in supporting small and medium sized business with all of their information system, communication and business needs.

17. Hence its resources are exchanged on a regular basis. In contrast to closed system, open systems perspective views an organization as an entity that takes input from environment, transform it and releases output to the environment with reciprocal effects on the organization itself along with the environment in which it operates. Companies use inputs as labor, funds, equipment and materials to produce goods and provide services, designing subsystems to attain their goals.

18. Characteristics of open systems There is importation of energy from the environment, eg, resources and people Through put,that is, transforming the resources available into something useful Output, exporting some of the resources to the environment Differentiation, specialization, integration and coordination of outputs made They have flexible boundaries since it interact with the environment. It contains subsystems which help in converting input into output

19. Benefits of system They promote effective problem solving There is continuous feedback and response results which help in better planning, intelligent designs, useful products and necessary relevant services Subsystems help in resolving conflicts as well as allocating resources

20. Limitations The system has disturbances of uncontrolled inputs that affect the processed resources within the system Example An example is the internet whereby one is able to contribute his or her ideas and download stuff from the internet.

21. FEEDBACK CONTROL SYSTEMS This is system which allows for feedback, meaning that a portion of the systems output is retained and used as input again to the system. This part of the output which is used as input again is what we call the feedback.

22. A feedback control system often uses the function of a prescribed relationship between the output and reference input to control the process of resources in that system. The difference between the output of the process under control and the reference input is amplified and used to control the process so that the difference is continuously reduced.

23. Characteristics of system Output can be retained and used as input again Provides feedback Uses interfaces to permeate information bottom up and top down

24. Advantages of system Many systems are subject to extraneous disturbances which causes the system to provide an inaccurate output hence feedback control systems have the beneficial aspect that the effect of distortion, noise and unwanted disturbances can be effectively reduced. It provides management with meaningful information on how effective its planning effort was. If feedback system indicates little variance between standard and actual performance, this is evidence that planning was generally target. Feedback control systems can help enhance employee’s motivation.

25. Disadvantages of system It is expensive to set up, and the cost of feedback is first manifested in the increased number of components and the complexity of the system. The major drawback is the time the manager may get the information, the damage might already have been done thus making the feedback irrelevant.