网络工程专业外文翻译.doc

毕业设计外文资料翻译题 目 基于WEB的网上选课系统的设计与实现 Key Techniques for Web CourseChoosing System Design and ConstructionAbstract：The Web CourseChoosing is the core that the credit system management reforms ，at present，the Web CourseChoosing system that every enterprises and colleges and universities already develop out，13o sttong or because of the diversity managing a pattern or because of system general availability，can be used being put in use directly having pretty big difficultyDeveloped out the Web CourseChoosing adapting to our college credit system requiresIn this paper，three key techniques of W eb Co urseChoosing design were given：O0，system security。Data optimizedUsing JSP technology，the Web CourseChoosing system with the functions of data input，query，statistics was also givenGave technical and methodology supports for understanding the Web CourseChoosing system structural design，making full use of current practical projects，and solving the practical problems as well as paved the way of implementation of the Web CourseChoosing system based credit support systemKey words：Web coursechoosing ；system design；key techniques；constructionIntroductionOnline course selection is an important part of teaching management of credit system, its characteristics can be summarized as a training model of diversity, autonomy of selective learning content, learning processes, learning flexibility of time and space. Flexible teaching management mode of a significant increase in impact of traditional, manual approach does not suit the new management mode, all colleges and universities in research to adapt to the new mode of teaching administration of network course selection system. At present, the College developed a system for close connection with the College teaching management mode, so the software versatility is not high, often only apply to colleges and universities. Software versatility of enterprise development was strong, but later maintenance and redevelopment more difficult. Based on the above reasons, Nanyang Institute of technology has developed online course selection system based on teaching management of credit system.1. Analysis of course-choosing system requirements 1.1 Students on course selection system functional requirements analysis Students in the courses of the requirements within the time period, log on to the system as an optional course, by-election, in the course selection process to be able to query the professional teaching program, instructors, such as scientific research, after the end of the course to be able to browse individual curricula, while allowing students access to personal files and all subjects.1.2 Teachers ' course-selecting system functional requirements analysisTeachers can use the system, maintain their own research and archival information, other teachers have access to part of the research, to be able to query your course schedule, can query the courses students, to entry the students, to on course score for statistical analysis, inspection under the teaching plan and teaching schedule, and so on.1.3 Manager course-selecting system functional requirements analysisManagers use the system to develop the teaching plan, have access to teaching schedule tasks, have access to all courses, students and teachers have access to basic information, to carry out all kinds of statistics, and so on.2. Key technologies for design of network course selection system and method 2.1 System design process2.1.1 Database designDatabase design is reasonable, is the key to the smooth running of the Office software system. Online course selection through to serious research, teaching and foreign colleges and universities in the province runs the entire process means of tracking the implementation of requirements analysis, design of the e-r model, associate system functions and data structures, and are reflected in the database design process. The system database reference education management information standard under, combination I school actual of Senate teaching management mode for design, while meet relationship database of entity integrity, and reference integrity, and user defined integrity requirements, using main key and outside key implementation data of integrity, using since defined of constraints conditions to reduced entry of complex of and errors rate, using trigger mechanism enhanced reference integrity and control database of changes, using storage process reduced database development personnel workload, improve database implementation speed. Foreground and background common to access a database server systems, taking into account the large amounts of data the system itself (such as students ' basic information basic information basic information, courses, teachers and more than more than 40) and the relationships between data, in accordance with the relational database paradigm of 3NF, as much as possible but without redundant data interdependence.2.1.2 Server configuration Server configuration requirements (with PC Server as an example): Operating system: Windows 2003, Linux, and UnixJava runtime environment-Jdk1. 3. 1Application server: Tomcat 4. 0 percent Database server: SQL Server 2000, Oracle 8i& Oracle 9i、Mysql3 23 PCServer hardware requirements: CPU: Intel PIII 800 or more (recommended P4 1. 6G) Memory: 512M (recommend 1G) Hard disk: 40G (reference 80G) Problem to focus on addressing the Security Server with the server configuration: (1) using the security features of the operating system, the operating system, such as users, user groups and access rights for strict rules, turn off services that may lead to security vulnerabilities, such as Telnet, FTP, SendMail, etc; (2) in respect of hardware disk array technology, guarantee the security of server-side data.2.1.3 Client development Development tools use the most popular Web programming language of JSP and JavaBean and Servlet technologies used in conjunction. Its advantage program page once compiled, dramatically improves program speed, followed by its good cross-platform.2.1.4 Commissioning and publishing Online course selection in three stages, namely normal course, lessons confirmed election results, and a by-election. Trial operation of the System 2003-level undergraduate students, students in the school to fill out course selection form within the required time, selected courses, which lasted a week. Normal course after the end of Dean's Office in the normal course results to remove are not eligible for classes teaching 8 classes in, while another 4 course class class. Students can be viewed on the course-choosing system Web site was removed, fill out the course teaching class list information, confirm the election results. After withdrawal, combined classes allow re-election of the same category of students in other courses. Normal course results when processing is complete, 143 people have a by-election. Dean's Office Manager for by-election results are processed, are still not eligible classes of the class withdrawn (that is no longer offering the course next semester). Students on the course to confirm the results, you can log in course selection system to print their own curricula. Through the trial operation of the system and achieve the goal of college book, since 2004 in the hospital.2.2 Design of key technologies and methods2.2.1 Object-oriented programming technology Method of object-oriented programming is a kind of support software reuse and modular design method of practical programming, its basic idea is to encapsulate and scalability. Packaging to bring software modularity, security, and so on, because there is no data coupling, objects with no action taken as a result of boundary effects, therefore, easier to maintain and modify . Scalability to leave system interfaces for easy integration with other systems, this system to work with the library, personnel management system management system, scientific management system, the Institute of financial management systems, Office OA system integration, people of the smooth realization of data export.2.2.2 System security technologyInformation security system construction of the first issue, of course-choosing system key information (such as student achievement, student information, and so on) safety is essential, must be developed at the design stage of the system construction of reliable security policy. This system from network traffic, server security, database management systems, systems, procedures, computer virus prevention and cure of the five regard provide security: (1) network communications: virtual local area network (VI, AN) services and firewall technologies. Your WEB server and database server system on College campus virtual subnet, only allow internal users to access, shielded external user access. For network protocol for qualifying, cute as h, p Protocol allows you to access, such as FrP, TeNet Protocol implementation. (2) Server security. (3) the database account permissions and database, database view, account operations record operating information, concurrency control, trigger actions, such as time tracking, in addition, enables automatic data backup data, and so on. (4) system. a Designed to dynamically set the user information in your application, access information, illegal may be effective in preventing the program from the system the client logs on to the system, and b. Application security control for database operations, will not cause half of the data submitted, or submitted error; c. Data encryption technology, the system user (such as students, teachers, and so on) registered passwords are encrypted to eliminate user Session such as technology gets the password. (5) computer virus prevention: install legitimate antivirus on the server side With anti-virus and firewall software, ensure that the functioning of the system.2.2.3 Database optimization techniques.(1) SQL statement optimization: SQL statement into the same purpose to be poor performance the performance of SQL statements. Using artificial intelligence, automatically overriding SQL statements, so as to find the best performance of an equivalent SQL statement. (2) indexed: improving query speed of the system.(3) create views and stored procedures3. Online course system construction 3.1 Construction of management systemSystems using Microsoft SQLServer2000 database in the background, foreground mining technology of JSP+JavaBean+Servlet and B/S mode Tomcat5. 0 as a WEB server, Internet course-selecting system features such as data entry, modification, querying, and statistics. Figure 1 is a system function module 3.2 System function(1) data maintenance functions: you can add, delete or modify data in a database operation, such as, and to deal with emergencies in the course selection process. (2) search function: can be based on user needs, such as students, teachers, and retrieve compliance data in a library. (3) data and statistics: statistical data in the database, and displayed as an icon, which found laws, provide reference for managers. (4) help: to provide users with timely, easy online help service. Figure 2 gives the student the normal course Interface, Figure 3 shows the student's schedule.4. Concluding remarks(1) after the course-choosing system, inputs to leap up in the students first, after four students ' course selection action, constantly modifying system functions, the current system has been improved, and user more human. (2) policy, system security. Throughout the development phase of the system, had a number of discussions around the policy of credit system in College, due to prior implementation and to develop policies, resulting in wide range adjustment system modules, the progress made in the development of the system. (3) course-choosing system data processing algorithms that require further study and discussion. Current system is used in the optimization level and first-come, first-served approach, courses are not guaranteed a fair and just.References:1 Hu Shijun, Wei-Chun yan, Rui Zhiyuan. Study on the current situation of credit system and its j. Gansu technology, 2004,20 (2): 151-153. 2-SA divisions warmth, Wang Shan. An introduction to database systems m. Beijing: higher education press, 2002. 3 Tang Yang, Wei Xiong, Chen Hongcheng. , And so on. Mechanism design and implementation of database triggers j. Application of electronic technology. 2005 (2): 16-18. 4 Liu De Chung Hom Kok. Principle and application of database system m. Wuhan: Hubei people s press. 2003.5 Guo Haifeng. Yang Guogui. Oracle database performance tuning techniques and implementation j. Computer engineering. 2006. 32 (19): 82-94.网上选课系统设计的关键技术及系统的构建摘要：学生选课是学分制管理制度改革的核心。目前，各企业及高校已经研制出的网上选课系统，或因管理模式不同或因系统通用性不强，使得直接投入使用有相当大的困难，为适应南阳理工学院学分制管理制度的改革需要，自主研发了网上选课系统。给出了网上选课系统设计的三个关键技术：面向对象、系统安全、数据优化，并利用JSP技术构建了网上选课系统，实现了数据录入、查询检索、报表统计等功能。为整体认识和解决基于学分制网上选课系统的结构方案设计，解决设计中的各种实际问题提供了技术、方法和手段的支持，也为全面系统地实现学分制教学管理模式的构建奠定了基础。关键词：网上选课；系统设计；关键技术；构建引 言网上选课是学分制教学管理的重要组成部分，其特点可以概括为培养模式的多样性、学习内容的选择性、学习进程的自主性、学习时间与空间的灵活性等。灵活性的大量增加严重冲击传统的教学管理模式，手工处理方式已不能适应新的管理模式，各高校都在探索研究适应新的教学管理模式的网上选课系统。目前各高校自主研发的系统因紧密结合所在院校的教学管理模式，所以软件通用性不高，往往仅适用于所在高校。企业开发的软件通用性虽强，但后期维护及二次开发比较困难。基于上述原因，南阳理工学院自主研发了基于学分制教务管理的网上选课系统。1 网上选课系统需求分析11 学生用户对选课系统功能需求分析学生要求在规定的选课时间段内，登录系统进行选课、补选，在选课过程中能够查询本专业教学计划、任课教师的科研情况等，选课结束后能够浏览个人课程表等，同时允许学生查阅个人档案及各科成绩。12 教师对选课系统功能需求分析教师能够通过使用该系统，维护自已的科研及档案信息，能够查阅其他教师部分科研情况，能够查询自己的课程安排情况，能够查询所带课程的学生情况，能够对学生成绩进行录入，能够对课程成绩情况进行统计分析，能够查阅专业教学计划及下期教学安排等等。13 管理者对选课系统功能需求分析管理者使用该系统，能够制定各专业教学计划，能够查阅教学任务安排情况，能够查阅全院课表，能够查阅学生及教师的基本情况，能够进行各类统计等等。2 网上选课系统设计的关键技术与方法21 系统设计的过程211 数据库设计数据库设计是否合理，是软件系统能否顺利运行的关键之处。网上选课系统通过到省内、外高校认真调研、教学运行全过程追踪等手段实施需求分析，进行ER模型设计，将系统功能与数据的结构关联起来，并反映在数据库设计过程中。该系统数据库参照教育管理信息化标准，结合我校实际的教务教学管理模式进行设计，同时满足关系数据库的实体完整性、参照完整性、用户定义完整性要求，利用主键和外键实现数据的完整性，利用自定义的约束条件来减少录入的复杂度和出错率，利用触发器机制增强引用完整性和控制数据库的变动，利用存储过程减少数据库开发人员工作量，提高数据库执行速度。系统的前台与后台共同访问一个数据库服务器，考虑到系统本身大量数据信息(如：学生基本信息、教师基本信息、课程基本信息等40多个)及数据之间的关系，依照关系数据库的3NF范式，尽量做到数据相互依赖但不造成冗余。212 服务器配置服务器配置需求(以PC Server为例)：操作系统：Windows 2003、Linux、UnixJava运行环境-Jdk131应用服务器：Tomcat 40以上数据库服务器：SQL Server 2000、Oracle 8i&Oracle 9i、Mysql323PCServer硬件需求：CPU：Intel PIII 800以上(推荐P4 16G)内存：512M 以上(推荐1G)硬盘：40G以上(推荐80G)服务器配置后要着重解决服务器的安全问题：(1)利用操作系统安全功能，对操作系统用户、用户组及访问权限等作严格规定，关掉可能导致安全漏洞的服务，如Telnet、FTP、SendMail等；(2)在硬件方面采用磁盘阵列技术，保证服务器端数据的安全性。213 客户端开发开发工具选用目前最为流行的网络编程语言JSP，并结合使用JavaBean 和Servlet技术。其优点在于程序页面一次性编译，大大提高了程序的访问速度，其次是其具备良好的跨平台性。214 试运行及发布网上选课分三个阶段，即正常选课、确认选课结果、退补选课。该系统在2003级本科生中试运行，学生在学院规定的时间内进行填写选课单、选定课程，历时一周。正常选课结束后，教务处根据正常选课结果，撤销不符合开班条件的课程教学班8个，同时对另外4个课程教学班进行合班。学生可以在网上选课系统网站上查看被撤课程、补撤教学班的学生名单等信息，确认选课结果。撤、合班后允许学