1、 计算机类毕业 外文翻译 The Phase to Develop the system With the societys development, the personal relationship is day by day intense. How enhances the personal relationship, reduces the management cost, the enhancement service level and pensonal competitive ability, is every one superintendent most matter of
2、 concern. More and more superintendents thought the implementation computer scientific style management solves this question. Management information systems (MIS), are information systems, typically computer based, that are used within an organization. World net described an information system as a
3、system consisting of the network of all communication channels used with an organization. Generally speaking, MIS involved the following parts: 1 Conduct a Preliminary Investigation （ 1） What is the objective of the first phase of the SDLC? Attention: SDLC means Systems Development Life Cycle. The o
4、bjectives of phase 1, preliminary investigation, are to conduct a preliminary analysis, propose alternative solutions, describe the costs and benefits of each solution, and submit a preliminary plan with recommendations. The problems are briefly identified and a few solutions are suggested. This pha
5、se is often called a feasibility study. （ 2） Conduct the preliminary analysis In this step, you need to find out what the organizations objectives are and to explore the nature and scope of the problems under study. Determine the organizations objectives: Even if a problem pertains to only a small s
6、egment of the organization, you cannot study it in isolation. You need to find out what the overall objectives of the organization are and how groups and departments with in the organization interact. Then you need to examine the problem in that context. Determine the nature and scope of the problem
7、s: you may already have a sense of the nature and scope of a problem. However, with a fuller understanding of the goals of the organization, you can now take a closer look at the specifics. Is too much time being wasted on paperwork? On waiting for materials? On nonessential tasks? How pervasive is
8、the problem within the organization? Outside of it? What people are most affected? And so on. Your reading and your interviews should give you a sense of the character of the problem. （ 3） Propose alternative solutions In delving into the organizations objectives and the specific problems, you may h
9、ave already discovered some solutions. Other possible solutions may be generated by interviewing people inside the organization, clients or customers, suppliers, and consultants and by studying what competitors are doing. With this data, you then have three choices. You can leave the system as is, i
10、mprove it, or develop a new system. Leave the system as is: often, especially with paper-based or no technological systems, the problem really isnt bad enough to justify the measures and expenditures required to get rid of it. Improve the system: sometimes changing a few key elements in the system u
11、pgrading to a new computer or new software, or doing a bit of employee retraining, for example will do the trick. Modifications might be introduced over several months, if the problem is no serious. Develop a new system: if the existing system is truly harmful to the organization, radical changes ma
12、y be warranted. A new system would not mean just tinkering around the edges or introducing some new piece of hardware or software. It could mean changes in every part and at every level. （ 4） Describe costs and benefits Whichever of the three alternatives is chose, it will have costs and benefits. I
13、n this step, you need to indicate what these are. The changes or absence of changes will have a price tag, of course, and you need to indicate what it is. Greater costs may result in greater benefits, which, in turn, may offer savings. The benefits may be both tangiblesuch as costly savings and inta
14、ngiblesuch as worker satisfaction. A process may be speeded up, streamlined through the elimination of unnecessary steps, or combined with other processes. Input errors or redundant output may be reduced. Systems and subsystems may be better integrated. Users may be happier with the system. Customer
15、s or suppliers may interact more efficiently with the system. Security may be improved. Costs may be cut. （ 5） Submit a preliminary plan Now you need to wrap up all your findings in a written report, submitted to the executives(probably top managers) who are in a position to decide in which directio
16、n to proceedmake no changes, change a little, or change a lotand how much money to allow the project. You should describe the potential solutions, costs, and benefits and indicate your recommendations. If management approves the feasibility study, then the systems analysis phase can begin. 2 Do a De
17、tailed Analysis of the System （ 1） What tools are used in the second phase of the SDLC to analyze data? The objectives of phase 2, systems analysis, are to gather data, analyze the data, and write a report. The present system is studied in depth, and new requirements are specified. Systems analysis
18、describes what a system is already doing and what it should do to meet the needs of users. Systems designthe next phasespecifies how the system will accommodate the objective. In this second phase of the SDLC, you will follow the course prescribed by management on the basis of your phase/feasibility
19、 report. We are assuming what you have been directed to perform phase 2to do a careful analysis of the existing system, in order to understand how the new system you propose would differ. This analysis will also consider how peoples positions and tasks will have to change if the new system is put in
20、to effect. In general, it involves a detailed study of: The information needs of the organization and all users； The actives, resources, and products or any present information systems； The information systems capabilities required to need the established information needs and user needs. （ 2） Gathe
21、r data In gathering data, systems analysts use a handful of tools. Most of them not tem ply technical. They include written documents, interviews, questionnaires, observation, and sampling. Written documents: a great deal of what you need is probably available in the form of written documents, and s
22、o on. Documents are a good place to start because they tell you how things are or are supposed to be. These tools will also provide leads on people and areas to pursuer further. Interviews: interviews with managers, workers, clients, suppliers, and competitors will also give you insights. Interviews
23、 may be structured or unstructured. Questionnaires: questionnaires are useful for getting information for large groups of people when you cant get around to interviewing everyone. Questionnaires may also yield more information if respondents can be anonymous. In addition, this tool is convenient, is
24、 inexpensive, and yields a lot of data. However, people may not return their forms, results can be ambiguous, and with anonymous questionnaires youll have no opportunity to follow up. Observation: no doubt youve sat in a coffee shop or on a park bench and just alone a person is watching. This can be
25、 a tool for analysis, too. Through observation you can see how people interact with one another and how paper moves through an organization. Observation can be non-participant or participant. If you are a non-participant observer, and people knew they are a participant observer, you may gain more in
26、sights by experiencing the conflicts and responsibilities of the people you are working with. （ 3） Analyze the data Once the data is gathered, you need to come to grips with it and analyze it. Many analytical tools, or modeling tools, are available. Modeling tools enables a systems analyst to presen
27、t graphic representations of a system. Examples are CASE tools, data flow diagrams, systems flow charts, connectivity diagrams, grid charts, decision tables, and object-oriented analysis. For example, in analyzing the current system and preparing data flow diagrams, the systems analyst must also pre
28、pare a data dictionary, which is then used and expanded during all remaining phases of the SDLC. A data dictionary defines all the elements that make up the data flow. Among other things, it records what each data element is by name, how long it is, are where it is used, as well as any numerical val
29、ues assigned to it. This information is usually entered into a data dictionary software program. The Phase: Design the System （ 4） At the conclusions of the third phase of the SDLC, what should have been created? The objectives of phase 3, systems design, are to do a preliminary design and then a de
30、tail and to write a report. In this third phase of the SDLC, you will essentially create a rough draft and then a detail draft of the proposed information system. （ 5） Do a preliminary design A preliminary design describes the general foundational capabilities of proposed information system. It revi
31、ews the system requirements and then considers major components of the system. Usually several alternative systems are considered, and the costs and the benefits of each are evaluated. Some tools that may be used in the preliminary design an the detail design are following: CASE tools: they are soft
32、ware programs that automate various activities of the SDLC in several phases. This screen is from one of their banking system tools. It shows a model for an ATM transaction. The purchaser of the CASE tool would enter details relative to the particular situation. This technology is intended to speed
33、up to the process of developing systems and to improve the quality of the resulting systems. Project management software: it consists of programs used to plan, schedule, a control the people, costs, and resources required to complete a project on time. 3 A detail design A detail design describes how
34、 a proposed information system will deliver the general capabilities in the preliminary design. The detail design usually considers the following parts of the system, in this order: output requirements, and system controls and backup. (1) Output requirements: the first thing to determine is what you
35、 want the system to produce. In this first step, the systems analyst determines what media the appearance or format of the output, such as headings, columns, and menus. (2) Input requirements: once you know the output, you can determine the inputs, here, too, you must define the type of input, such
36、as keyboard or source data entry. You must determine in what form data will be input and how it will be checked for accuracy. You also need to figure out what volume of data the system can be allowed to take in. (3) Storage requirements: using the data dictionary as a quite, you need to define the f
37、iles and databases in the information system. How will the files be organized? What kind of storage devices will be used? How will they interface with other storage devices inside and outside of the organization? What will be the volume of database activity? (4) Processing and networking requirement
38、s, what kind of computer or computers will be used to handle the processing? What kind of operating system and applications software will be used? Will the computer or computers be tied to others in a network? Exactly what operations will be performed on the input data to achieve the desired output
39、information? What kinds of user interface are desired? (5) System controls backup: finally, you need to think about matters of security, privacy, and data accuracy. You need to prevent unauthorized users from breaking into the system, for example, and snooping in private files. You need to devise au
40、diting procedures and to set up specifications for testing the new system. Finally, you need to institute automatic ways of backing up information and storing it else where in case the system fails or is destroyed. 4 Develop/Acquire the System （ 1） What general tasks do systems analysts perform in the fourth phase of the SDLC? Systems development/acquisition, the systems analysts or others in the organization acquire the software, acquire the
