INFORMATION SYSTEM Basic System Concepts System: a collection of elements that interact to achieve a goal particular. According to Jerry FithGerald; system is a network of procedures interconnected, gathered together to perform an activity or completing a certain goal. System Characteristics: • Have a component; A system consists of a number of interacting components, working together form a unity. The components of the system can be a subsystem or parts of the system. Each system no matter how small, always contains the components or subsystems. Each subsystem has the properties of the system to perform a particular function and affect the overall system. A system can have a larger system called the supra-system, for example, a company can referred to as a system and industry that is larger systems can called the supra-system. If the industry is seen as a system, then companies can be called a subsystem. Likewise, if the employer is deemed as a system, then the accounting system is subsistence. • Limit system (boundary); Boundary is an area that limits the system between a system with a system that other or with the outside environment. Limit of this system allows a system viewed as a whole. Limit of a system showing the scope (scope) of the system. • The environment outside the system (environment); Is anything outside the boundaries of the system that affect the operation of the system. • Liaison system (interface); Is a media liaison between one subsystem to another subsystem. • Enter the system (input); Energy is put into the system. Input can be input maintenance (maintenance input) and input signal (input signal). Maintenance input is the energy that is inserted so that the system can operate. Signal input is the energy that is processed to obtain the output. For example in the system computer, the program is the maintanance inputs used to operate computer and data is input signal to be processed into information. • Output system (Output); Is the result of the energy processed by the system. • Processing systems (Process); Is the part that processes the input to be output as desired. • Target system; If the system does not have a target, then the operating system will not be any good. 2 Classification System: • abstract system; system in the form of thoughts or ideas that are not apparent physical (system of theology) Physical systems; an existing physical system (computer systems, accounting systems, production systems, etc..) • natural systems; system that occur through natural processes. (Solar system, outside the system space, etc. reproductive system. Man-made systems; system designed by humans. Man-made systems that involve human interaction with machines called humanmachine system (example; information systems) • System Specific (deterministic system); operate with behavior that is predictable. Interaction of its parts can be detected with certainty that output of the system can be predicted (example: computer systems) Indeterminate systems (probabilistic system); system that conditions the future can not be predictable because it contains elements of probability. • Closed system (closed system); systems that are not related and are not affected with external systems. This system works automatically without interfering hands of outside parties. Theoretically such a system exists, but the reality is not there is a system that is completely closed, there was just Relatively closed system (in relatively closed, not completely closed). Open system (open system); system-related and affected by outside environment. More specifically known also called the automated system; that is part of man-made systems and berineraksi with control by one or more computers as part of the system used in modern society. Automated systems have several components, namely; �� Hardware (CPU, disks, printers, tape). �� software (operating systems, database systems, communication control program, application program). �� Personnel (who operate the system, providing input, output consumed and perform activities that support manual systems). The �� data (which must be stored in the system for a certain period). �� Procedures (instructions and policies for operating systems). Automated system is divided into a number of categories: ♦ On-line systems. On-line system is a system that receives direct input on the area where the input was recorded and produced output that could be a result computing in the areas where they are needed. Area itself can be broken down in scale, for example, hundreds of kilometers. Normally used for air freight reservations, railway reservations, banking, etc.. ♦ Real-time systems. Real-time system is a mechanism of control, data recording, processing is very fast so that the resulting output can be received in time relatively equal. The difference with on-line system is the unit of time used real-time typically a hundredth or a thousandth of a second on-line while still dalah scale of seconds or sometimes even a few minutes. Other differences, on-line usually 3 only interact with the wearer, while real-time interacting directly with wearer and the environment are mapped. ♦ Decision support system + system strategic planning. Systems that process transactions organizations on a daily basis and help managers make decisions, evaluate and analyze the organization's goals. Used for payroll system, the system reservations, accounting systems and production systems. Usually shaped statistical package, marketing package, etc.. This system not only records and displays the data but also mathematical functions, statistical data analysis and display of information in the form graphics (tables, charts) as a conventional report. ♦ Knowledge-based system. Computer programs are made close to the capabilities and knowledge of an expert. Commonly used hardware and specialized software such as LISP and PROLOG. Systems based on the basic principles are generally divided into: • The system is specialized; is a difficult system in an environment diterakpan different (eg systems biology; fish are transferred to landline) • large system; is a system that serves most of its resources to Daily care (eg dinosaurs as a biological system spends most of his life as eating and eating). • System as part of another system; system is always a part of the system larger, and can be divided into smaller systems. • developing systems; although not applicable to all systems but almost all system is always evolving. Perpetrators system consists of 7 groups: 1. User; In general there are three types of users, namely the operational, supervisory and executive. 2. Management; Generally consists of three types of management, namely management of users in charge address use where a new system implemented, the management system involved in the development of the system itself and the general management involved in strategic planning systems and decision support systems. Group management is usually involved with decisions relating to people, time and money, for example; "The system must be capable of performing the function of x, y, z, otherwise it should be developed within six months with the involvement of programmers from the department of w, with cost of x ". 3. Examiner; The size and complexity of systems that work and the natural form of organization where the system The conclusions need to be implemented to determine whether or not the examiner. Examiner usually determines everything under standard measures developed in many of its peers. 4. Analyzer systems; Among other functions as: - Archaeologists; namely that track how long the system is actually running, how the system is run and all matters relating to the old system. 4 - Innovators: namely that helps users develop and open up horizons for other possibilities. - Mediator; that is running the communications functions of all levels, among other users, managers, programmers, inspectors and other system actors may not have the attitude and the same light. - The head of the project; analyzer system should be more experienced personnel from the programmer or designer. Besides considering the analyzer system generally determined in advance in a job before the other work, is it's okay if the person in charge of work into the system analyzer portion. 5. Designing the system; Designing the system receives the results of analyzer systems in the form that the user needs not oriented to a particular technology, which is then transformed to design high level architecture and can be formulated by the programmer. 6. Programmer; Working in the form of program design results that have been received from the designer. 7. Operating personnel; Duty and responsibility at the center of the computer such as network, security hardware, software security, printing and backups. Actors may not required when the system is running is not large and does not require classification specifically to run the system. The basic point in system development Analyzer system is part of a team that works to develop a system that has high efficiency and meet the needs of end users. This development influenced by a number of things, namely: • Productivity, the current system needs more, better and faster. It needs more programmers and systems analysts are qualified, extra working conditions, the ability of users to float its own, language better programming, better system maintenance (generally 50% to 70% of resources are used for system maintenance), use of technical disciplines software and automated systems development. • reliability, time spent on testing the system in general spend 50% of the total system development time. Within 30 years a number of systems used in various companies encountered an error and ironically is not very easy to change it. If there errors, there are two ways you can do, which is tracking the source errors and must find a way to correct such errors by replace the program, eliminating a number of old statement or add number of new statements. • Maintabilitas, treatment includes; - Modification of the system according to the development of hardware to improve processing speed (which plays an important role in the operation system), - Modification of the system according to developmental needs of the user. Between 50% to 80% work performed on most systems development undertaken to revision, modification, conversion, enhancement and tracking errors. 5 Basic Concepts of Information: Information: data that has been processed into a form that has meaning for the recipient and may be a fact, a value that is useful. So there is a process of transformation of data become an information == input - process - output. Data is the raw material for some information. The difference of information and data is very depending on the relative value of management that requires a use for. An information for certain management level could be for management-level data on it, or otherwise. Representation of information: information figuratively, for example: binary representation. Quantity of information: the unit of measure information. Depending on the representation. For representation binary unit: bit, byte, word, etc.. Quality of information: the bias against error, because: measurement errors and collection, failure to follow procedures prmrosesan, loss or data is not processed, or recording error correction data, error history file / master, error berfungsian systems lack the processing procedure. Age of information: when, or until when an information has value / meaning to users. There informasion condition (refer to the particular point in time) and operating information (stating a change in a range of time). Information quality; depends on 3 things, that information must be: • Accurate, meaningful information should be free from mistakes and not biased or misleading. Accurate also means that information must clearly reflect masudnya. • Stay on time, means that information that came at the recipient should not be too late. • Relevant, means that information menpunyai benefits to the wearer. Relevance information for each person differ from one another. Information Value; determined from two things, namely the benefits and costs to get it. One information said to be worth when its benefits are more effective than the cost get it. Measurement of the value of information is usually associated with cost analysis effectiveness or cost benefit. Information Systems Definition: An integrated system capable of providing useful information for users. Or; An integrated system or human-machine systems, to provide information to support operations, management in an organization. These systems utilize hardware and computer software, manual procedures, model and database management. 6 From the above definition there are some keywords: 1. Computer-based Systems, Man / Machine - Based computer: computer designers must understand the knowledge and processing information - Human machine systems: there is an interaction between man and machine as the manager as a tool to process information. There is a manual process that must be done human and automated processes that are by machine. Therefore we need a procedures / manual system. 2. Integrated data base system - The use of databases together (sharing) in a data base management system. 3. Supporting Operations - The information processed and generated used to support the organization's operations. The term Information System = Management Information System = Information Processing System = Information Decision System = Information System. Everything refers to a computer-based information system designed to support the operation, management and decision-making functions of an organization. According to Robert A. Leitch; information system is a system within an organization which bring together the needs of daily transaction processing, support operations, are managerial and strategic activities of an organization and provide a specific outside party with the necessary reports. Physical Component Information System: 1. Computer hardware: CPU, Storage, device Input / Output, Terminal for interaction, data communication media 2. Computer software: system software (operating system and utilitinya), common software applications (programming language), software applications (application accounting etc.). 3. Databases: storing data on computer storage media. 4. Procedure: step-by-step use of system 5. Personnel for operations management (SDM), includes: - Clerical personnel (to handle the transaction and processing the data and perform inquiry = operator); - First level manager: to manage the data processing is supported with planning, scheduling, identification of situations out-of-control and decision making levels lower middle. - Staff specialist: used for the analysis for planning and reporting. - Management: for making periodic reports, requests periodicals, special analysis, Khsusus reports, supporting the identification of problems and opportunities. Applications = + program operating procedures. 7 RELATIONSHIP WITH INFORMATION SYSTEMS MANAGERS On the one already mentioned that one of the components of the system information is personnel as the manager of information. Therefore the relationship between information systems very closely with the managers. System information required depends on the needs of managers. Management information systems are organized in a management structure. Therefore shape / type the necessary information systems in accordance with the level of management. Top Level Management: strategic planning, policy and decision making. Manejemen Intermediate Level: for tactical planning. Manejemen Level Below: for planning and supervision of operations Operator: for transaction processing and responding to requests. For the development of an information system necessary organizational management structure personnel. Strutktur essentially: Director of Information Systems Systems Development Manager Systems Analyst Programmer Computers and Operations manager. Variations in management structure is very dependent on the Managerial Efficiency vs. User Service. INFORMATION SYSTEM DESIGN The design of information systems is the development of new systems from old systems There, where the problems occur on the old system is expected to be resolved in the new system. INFORMATION SYSTEM DEVELOPMENT LIFE CYCLE (SYSTEM DEVELOPMENT LIFE cycles - SDLC) Conceptually the development cycle of an information system is as follows: 1. Systems Analysis: analyze and define problems and possible solutions for information systems and organizational processes. 2. System Design: designing output, input, file structures, programs, procedures, hardware and software required to support information systems 3. Development and Testing System: building the software needed to support system and perform testing accurately. Perform installation and testing of the hardware and operating software 4. System Implementation: switching from the old system to new system, conduct training and guidance as necessary. 5. Operation and Maintenance: operating system support information and make changes or additional facilities. 6. Evaluation System: sejauih evaluate where the system has been built and how well system has been operated. 8 The cycle takes place repeatedly. The cycle above is a classic model of information systems development. New models, such as prototyping, spiral, 4GT and combination of the classical model developed above. ANALYSIS SYSTEM The reason the importance of starting the analysis of the system: 1. Problem-solving: the old system did not function in accordance with needs. For that analysis necessary to fix the system so it can function as needed. 2. New needs: the need for new in the organization or the environment so that it is necessary modifications or additional information systems to support organization. 3. Implement new ideas or technologies. 4. Improve overall system performance. Limitation of System Analysis: Activities conducted in the analysis system must be able to answer general questions, as follows: 1. The new system is to be built? or 2. System is to be added or modified on the old system that has been there? To that must be answered in detail questions: 1. What information is needed? 2. By whom? 3. When? 4. Where? 5. In what form? 6. How do I get it? 7. Where's he from? 8. How do I collect it? Proposal conduct systems analysis; Contains: 1. The definition of clear and consistent about the reasons for the analysis 2. The definition limits the analysis to be performed 3. Identify the facts that will be collected and studied for analysis 4. Identify sources where the facts can be obtained 5. Description of goals and constraints that may be in the analysis 6. Projections of possible problems that will occur during the analysis 7. Tentative schedule analysis The sources of facts that can be studied for system analysis: 1. Existing system 2. Other internal sources: people, documents, and the relationship between those organizations or function there 3. External sources: interfaces with other systems, seminars, vendors, journals, textbooks and information or other disciplines that are outside the system 9 Analysis Framework: 1. Analysis of the level of decision makers (management organization): analyze organization, functions and information needs and information generated. 2. Analysis of the flow of information: identifying what information is needed, who requiring, where it came from. 3. The analysis of input and output. In this analysis techniques and tools used, al: interview, questionaire, observation, sampling and document gathering, charting (organization, flow, dfd, ER, OO, etc.), decision tables and matric Report the results of the analysis: Report the results of the analysis must contain: 1. Description of the reason and scope (limitations) analysis 2. Description of existing systems and operations. 3. Description of the purpose (objective) and system constraints 4. The description of the problems and potential problems not resolved 5. A description of the assumptions taken by the system analyst during the analysis process 6. The recommendations of the new system and the need for preliminary design 7. Projected resource requirements and costs are expected to include in the design new systems or modify it. These projections include eligibility for the next. Category aspects of feasibility: 1. Technical Feasibility: the feasibility of hardware and software. 2. Economic Feasibility: are there any advantages or disadvantages, common operational efficiency organization. 3. Feasibility operations: associated with operating procedures and the people who run organization 4. Feasibility schedule: can use models such as PERT and scheduling Gantt Chart. Whether or not feasible development schedule. The final result analysis system (decision): 1. Stop the job, because the proposal is not feasible. 2. Wait a moment, because there are other considerations. 3. Modification, management decided to modify prososal with other subsystems. 4. Process on the condition, there are eligibility requirements. 5. Process unconditionally, all terms are met. Submissions will be accepted and the process proceeds to initial design. System development cycle according to J. Kelly F.; 1. Research systems a. Definition of the scope. b. Research studies 2. Analysis and design of the system a. Research studies b. Data collection and analysis c. System design d. Implementation plan 10 3. System development a. Development b. Testing c. Operation d. Treatment System development cycle according to Martin and Thomas Harrel L; 1. Conception system 2. Preliminary analysis a. Pendefinisan preliminary issues b. Investigation c. Preparation of the proposed system 3. System design a. Detailed analysis b. Designing a decision c. Designing target d. System design 4. Programming a. Re solve design b. Develop a flow chart outlines c. Writing instruction program d. Assemble a program e. Preparing data for test f. Testing g. Checking results h. Diagnose faults i. Correct program j. Start the system testing 5. Documentation 6. Installing the system 7. Operating system SYSTEM DESIGN Analysis system used to answer the question what? While the design used to answer the question how? The design concentrates on how the system is built to meet the needs analysis phase. The elements of knowledge related to the design process: 1. Resource organization: the organization rests on five elements, namely: man, machines, materials, money and methods. 2. Information needs of users: information obtained from users during the phase analysis system. 3. System requirements: results of the analysis system. 4. Data processing methods, whether: manual, elektromechanical, puched card, or computer base. 5. Data operations. There are several basic operations of data, ie: capture, classify, arrange, summarize, calculate, store, retrieve, reproduce and disseminate. 6. Design aids, such as: dfd, DCD, dd, decision tables, etc.. 11 The basic steps in the design process: 1. Defining the purpose of the system (defining the system goal), not only based on information users, but also a study of abstraction and the overall characteristics system information needs. 2. Building a conceptual model (develop a conceptual model), a picture which describes the overall system as a functional unit of the system unit. 3. Applying kendala2 organization (applying organizational contraints). Apply the constraints of the system to obtain the most optimal system. Organizational elements is a constraint, while the functions to be optimized is: performance, reliability, cost, schedule instalation, maintenability, flexibility, grouwth potential, life expectancy. Models for optimal system can be described as a model which contains: the needs of system and organizational resources as input; weighting factor comprises functions optimally at the top, and the total value of the should be optimized from the weighting factor. 4. Defining the data processing activities (defining data processing activities). This can be done by defining the approach of input-process-output. To determine this iterative process is required as follows: a. Mengidentifikasn output is paramount to support / achieve the objectives of the system (System's goal) b. Field lists the specific information needed to provide the output c. Identify the input data needed to build spesifikik field necessary information. d. Describe the data processing operations are applied to process input be output as needed. e. Identify elements of input into the input section and stored during the processing of inputs into outputs. f. Repeat steps ae continuously served until all the required output is obtained. g. Build a data base that will support the effectiveness of the system to meet needs of the system, data processing and data characteristics. h. Based on system development constraints, priority support, the estimated cost of development; reduce the input, output and extreme processing i. Define the various control points to regulate the activities of data processing determines the general quality of data processing. j. Complete the input and output format is best for system design. 5. Setting up a system design proposal. This proposal is necessary for the management whether the next process feasible to proceed or not. Things that need to be prepared in preparation of this proposal are: a. Restate the reasons for starting work on the system including goal / objective specific and related to user needs and design system. b. Setting up a simple model however, a comprehensive system that will filed. c. Showing all available resources to implement and care system. 12 d. Identify critical assumptions and issues that have not been addressed that may affect the final system design. While the format of the design proposal is very berfariasi but contain halhal above. Basic Principles of Design There are two basic principles of design, a.l: 1. Monolithic system design. Emphasis on systems integration. Resource which could integrated to obtain an effective system, especially in cost. 2. Modular system design. Emphasis on solving the functions that have low idependensi into modules (functional subsystem) are separated so that allows us to concentrate on design per module. An information system can be broken down into seven functional subsystems, ie: data collection, data processing, file updates, data storage, data retrival, report information and data processing controls. A general guideline in the design of the functional subsystems of a system of information: 1. Sources of data should be collected only once as an input to the system information. 2. Accuracy of data sources is highly dependent on the number of steps to his records, collect and prepare data for processing. The fewer steps the more accurate. 3. Data generated from computer-based systems should not be inserted again into system. 4. Timing necessary to collect data must be smaller than the timing information is required. 5. Keep the selection means the most optimal data collection 6. Data collection should not be on-line, but depending on the needs of the information. 7. All data sources must be in the validation and edited immediately after the collect. 8. Data is already validated, should not be validated in further processing. 9. Total control must be checked again immediately before and after a processing activity great done. 10. Data must be stored only in one place in the database unless there is a constraint system. 11. All data fields should have an entry and maintenance procedures. 12. All data must be printed in a format that is meaningful for audit purposes. 13. Transaction file must be at least maintained in a cycle of updates to the database. 14. Backup and security procedures must be provided for all fields of data. 15. Any non-sequential files need to have periodic reorganization procedures. 16. All data fields must have the date of update / access the last save. To analyze the system effectively, we need more than just a device modeling; the method. This method changed from time to time in accordance with technological developments. This cycle tends to repetition significant change with discovery of the fourth and last generation language in which fifth-generation approach with object-oriented paradigm and the compatibility between models. There are basically two methods of approach in building the system, the first of topdown. In this method the system is derived from the global mapping is then will decline to a more descriptive. This method is analogous to making homes starting from the most fundamental aspects of the foundation down to the smallest 13 such as a faucet in the bathroom. The second method is bottom-up, where the system mapped from the smallest unit so that the largest units, such as automobile assembly. On 1980_an early start designing a technique known as structured by using the concept parallel and cycle, for example between test programs and programming work can be done parallel, and if there is something wrong when implementation is carried out surveys, analysis and redesign that replaces the classical method of designing an inclined serial. In principle, designing the system as a structured activity covers: �� Survey; serves to determine user requirements, errors in the old system, set goals for design, automation systems proposed feasible and acceptable, and prepare a report containing a survey of all something, at the points above. �� analysis system; combine user survey report and policy be specification using structured modeling. �� Design; implement the desired model user. �� Implementation; represents the results of the design into programming. The �� trial design; test the whole structured specifications. �� Testing end; test the overall system. �� Description of the procedure; creation of written technical reports and user operation. �� Conversion database; convert the data, because the word data is plural in meaning previous system.
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