一种新型的基于Web的在线考试系统的计算机科学教育

1、A Novel Web-Based Online Examination System For Computer Science Education一种新型的基于Web的在线考试系统的计算机科学教育A Novel Web-Based Online Examination System For Computer Science EducationYuan Zhenming,Zhang Liang,Zhan GuohuaAbstract Web-based Examination System is an effective solution for mass education evaluati

2、on. We have developed a novel online examination system based on a Browser/Server framework which carries out the examination and auto-grading for objective questions and operating questions,such as programming,operating Microsoft Windows,editing Microsoft Word,Excel and PowerPoint,etc. It has been

3、successfully applied to the distance evaluation of basic operating skills of computer science,such as the course of computer skills in Universities and the nationwide examination for the high school graduates in Zhejiang Province,China.Index Terms Examination system,Auto-grading system,Web-based,DCO

4、M1. IntroductionIn China, the education for basic computer operating skills has been broadly launched. The skills include the operating of Windows, MS Office, Networking skills, etc., which are the foundation of a combination of different courses, as well as of electronic-government. Now, every unde

5、rgraduate must pass the course of the Computer skills, while every civil servant must pass the corresponding Computer Operating Exams. Furthermore, the basic computer education in high schools is in process. Since the late 1990s, hundreds of thousands of people have taken part in different levels of

6、 computer education and testing in Zhejiang Province. It is necessary to build a Web-based learning and examination system for such a large number of people,as an effective solution to mass learning and evaluation of basic computer education.Several Web-based learning and testing systems have been d

7、esigned, such as WebCT1, QUIZIT2, ASSYST3, and PILOT4. The most widely used question types of the Web-based examination system are objective tests and quizzes which assume simple answers that can be formally checked and easily evaluated online. The typical questions are limited to yes/no questions,

8、multiple -choice/singleanswer questions, multiple-choice/multiple-answer questions, and fill-in questions with a string and numeric answer.5 Richer types of answers in these systems need to be graded manually by the course graders or the instructors. In addition, these systems do not support testing

9、 operating skills, such asWindows printer setup operation and Word editing, etc. in the client computer.Our examination system for basic computer operating skills has the following characteristics: (1) The question types include not only objective questions, but also operating questions as Windows,

10、MS Word, MS Excel, Internet skills, etc. (2) The goal of the learning and testing system is to train the practical skills. As a result, operating and testing in the actual environment of the client machine is the best learning method. (3) It is urgent to develop an automatic grading system which can

11、 grade the operating questions as well as the objective ones. However, the previous Web-based learning and testing system cannot support such functions.We have developed a novel online examination system based on a Browser/Server framework using state-of-art computer technologies, which carries out

12、the examinations for basic computer operating skills including objective tests, Visual Basic programming, Microsoft Windows operating , Word, Excel and PowerPoint editing, Internet and Email skills, etc. It has also implemented automatic grading online.2. System ArchitectureOur web-based examination

13、 system is a distributed collaborative system which is based on DCOM technology. It has four major components : the examination preparation system, the examination system, the examination monitor system and the auto-grading system.The preparation system is used to manage question storage, assign tes

14、t ID and schedule the test. The question database is composed of the questions, a set of possible answers, the question types and other metadata, which are indexed by several factors, such as topics, keywords, complexity and difficulty, etc. The database is open to teachers, allowing them to add que

15、stions and answers by template.The examination System is a web-based testing interface for students , called WOES , which include the following key features: client side control, time control, security control and auto-installation. Benefiting from DCOM technology, the system can install and update

16、itself conveniently, better than the C/S framework. Because the system is established on the Web, the systematic security faces a severe challenge. We guarantee the security by cryptography, real-time monitoring system and data transmission encryption. The cryptography is used to validate student id

17、entification before testing.The real-time monitoring system requires students not to leave the computer during the test by face tracking technology. The data transmission encryption system transmits the examination question and result in secret form through the network to the server. The examination

18、 monitor system is also the manager of the examination system, by which we can monitor the test processing, carry out test ID statistic and collect the answers, etc.The auto-grading system is designed by the fuzzy matching algorithm and the macro programming technology, which is seasoned with variab

19、le question types.3. Web-Based Online Examination System3.1 The aim of the examination systemAs a universal examination system for the education of basic computer operation, it must meet the following requirements:61. A reasonable question storage, which must conform to the general outline of the ex

20、am.2. A practical interface. There are two types of exam interfaces. One is the simulation, the other is the actual environment. The second scheme will give the student more flexibility because of the practical nature of computer skills.3. A range of question types , such as objective questions, ope

21、rating questions, design questions, information retrieval, group testing, etc.4. A safety and reliable examination system.3.2 The components of WOESThe Web based Online Examination System (WOES) is a multi-layer system which is composed of the Web Server, Database Server, WOES middleware Server, WOE

22、S client module and Browser, such as Internet Explorer. In this system, we use the Internet Information Server 4.0(IIS) as the Web Server, the Database Server is Microsoft SQL Server 7.0.The kernel of WOES is the WOES middleware Server and the WOES client module, which is designed according to Micro

23、soft DCOM standards. DCOM is the binary COM objects extension jointing LAN, WAN and Internet, which can instance and bind objects over different network. It is an advanced network protocol used to cooperate with COM based components of two processes in different locations. The WOES middleware Server

24、 is a server-side component providing communication interfaces between WOES clients and the Web Server or Database Server. The WOES client is a client-side component which is called by the Browser to control the client computer and submit or receive information from the WOES Server. This technology

25、guarantees the flexibility and the potential for extension of the test system. In addition, it allows access to local files, whereas in conventional systems, the IE security prevents such accessBenefiting from DCOM, the WOES clients can be downloaded or updated automatically from WOES middleware Ser

26、ver on the Internet. They can also move from one client to the other and communicate with the WOES Server. The system acts like an Agent society, which is a centralized Agent system controlled by only the WOES Server.3.3 The key technologies of WOES1. A user-friendly interfaceWe use browser as our u

27、sers interface. The Browser interface has a uniform and consistent user interface. Almost everyone is able to use it skillfully. Therefore it can eliminate the differences of various exam systems and guarantee a fair test.2. Simplified system maintenanceSince the system is based on Browser/Server ar

28、chitecture, the teacher can update the system or the question database or examine the students database only in Server. It is not necessary to update the client system as the Client/Server must do.3. Central examination managementProfiting from the central controlled system, the teacher can easily c

29、ontrol the examination process, such as the beginning and end of the exam, collecting the answers and monitoring the students conditions on the teachers screen.4. SecurityThe most severe difficulty which the B/S based system faces is security, because in principle the web-based examination system ca

30、n be accessed on the Internet or WAN in a city. All the questions, materials and answers are transmitted in bits stream format after encoding, not in file format. It can ensure not only security in the transmission process, but also protect from invasion.When one student starts his test, the system

31、will distribute him a password produced according to his clients hardware and operation system environment. It can prevent cribbers to login from other clients imitating this student. The newest method to prevent the distant student from leaving the client or is making use of face detection and reco

32、gnition technology. Before the start of the exam, the student is asked to sit in front of the computer camera which can monitor the whole scene. Then the system will automatically recognize the students face and his identification. As soon as the validation is performed, the student must stay in fro

33、nt of the camera until the exam is finished.4. Auto-Grading SystemThe auto-grading system can automatically grade theanswers, which are collected from the examination system . It helps teachers to achieve the score with ease.There are two types of the grading: objective questions and operating quest

34、ions. Objective questions, such as choice questions, yes/no questions, and fill-in questions, can be graded effectively by accurate matching or fuzzy matching. But it is difficult to grade operating questions by simple matching technologies. A possible solution could be: (1) Reading the answer file

35、directly and comparing it to the key file. But this is not practical because the format of Microsoft Office files is complicated. Another solution is: (2) grading by using the Office OLE object. This method is convenient and efficient, but it has a big disadvantage: the source code of the grading sy

36、stem is closely related to the concrete question, which results in a large amount of work when the questions are changed.We propose a universalized grading system which is carried out on the basis of a database of key knowledge.First, we extract all possible knowledge points and store them in a trip

37、le form: (key, value, location). Then we produce the question file by labeling the question point directly on it; the system will add the corresponding question key to the standard key library. So, the last process of autograding system is to compare the answer file with the standard key library. Th

38、e auto-grading system also allows the teacher to add his /her own questions to our examination system.5. ConclusionWe have developed an overall solution to the examination system for practical computer skills . It provides a userfriendly platform of various questions for the basic computer education

39、 in Universities, civil servant training and nationwide examination for high school graduates in Zhejiang Province, Hundreds of thousands of students and teachers have used this system and agree that it has effectively raised the learning and testing efficiency.6. References1 WebCT,”Web Courses Toll

40、s”,http:/www.webCT.com.2 Tinoco, L., Fox, E. and Barnette, D. “Online evaluation in WWW-basedcourseware”, In Proceedings of the 28th SIGCSE Technical Symposium(1997), pp. 194-198.3 Jackson, D., Usher, M. “Grading student programs using ASSYS T”, In Proceedings of the 28th SIGCSE Technical Symposium

41、(1997), pp.335-339.4 Stina, B., Michael T., Stephen G., Roberto T., “PILOT: An Interactive Tool for Learning and Grading”, SIGCSEB: SIGCSE Bulletin,2000.5 Peter Brusilovsky and Philip Miller, “Web-based Testing for Distance Education”, Proceedings of WebNet'99, World Conference of the WWW and In

42、ternet, Honolulu, HI, Oct. 24-30, 1999, AACE, pp. 149-1546RuiMin Shen, Yiyang Tang, Tongzhen Zhang, “The intelligent assessment system in Web-Based Distance Learning Education”, FIE 2001.一种新型的基于Web的在线考试系统的计算机科学教育Yuan Zhenming1, Zhang Liang2, Zhan Guohua3摘要:基于Web的网上考试系统是一种为大众教育的评价有效的解决方案。我们已经开发一种在线考试

43、系统,它是基于浏览器/服务器架构.该系统已经发布了考试和自动评级;是关于客观的问题和操作问题，以供客观的问题和经营问题他作为一个程序，经营的Microsoft Windows ，编辑的Microsoft Word ， Excel和PowerPoint等等。她已经成功地应用于距离评价的基本操作技能的计算机科学，如过程的计算机技能，在大学和在全国范围内考试，为高中毕业生在中国浙江省进行实行。指数条款:考试系统和自动分级系统，它们都是基于Web的和DCOM的系统。1. 导言: 在中国，基本电脑操作技能的教育已广泛展开.这项技术包括经营的Windows的MS Office ，网络技巧等等，这是结合不同

44、的课程，以及作为电子政府的基础。现在，每一个本科生必须通过的计算机技能的考试.然而,每一位公务员必须通过相应的计算机操作考试过程。此外，在高中的过程中进行了计算机基础教育。自20世纪90年代末，在浙江省成千上万的人们开始参加不同的层次计算机教育和测试.这是非常有必要的,对于建立一个基于网络的学习和考试系统.它是为众多的人民，作为一个有效的解决办法去集体的学习和评价计算机基础教育的。几个基于Web的学习和测试系统已经被设计完，比如说WebCT 1 ， QUIZIT 2 ， ASSYST3和PILOT4。在线可以很容易使用最广泛的问题类型的基于Web的考试制度是客观的测试和测验，其中承担简单的答案

45、可以正式检查和评估。典型的问题是以有/无问题，多-choice/singleanswer问题有限的， multiple-choice/multiple-answer问题，并填写在的问题与一个字符串和数值答案。 5丰富类型的答案在这个系统中需要中年级学生或教员在这些系统需要手动的分级过程。此外，这些系统不支持的测试操作技能，例如在用户端电脑的windows打印机设置的运作和Word编辑等等。我们的考试制度，为基本的计算机操作技能有以下特点： （1）问题的类型，它不仅包括客观的问题，而且还经营如: Windows ，MS Word文字，使用MS Excel ，上网技巧等等的问题。（2）学习和测试系

46、统的目标是培养一个人的实用技能。因此,最好的学习方法是经营和测试在实际环境的客户机之上。（3）这是迫切需要建立一个自动分级系统，以可分级经营的问题和客观问题为目的。然而，往往是基于Web的学习和测试系统不能支持这样的功能。我们已经开发了一种新型的在线考试系统的.它是基于利用国家的最先进的电脑技术Browser/Server framework.它是实行电脑基本操作技能考试，主要包括客观的测试、Visual Basic编程，Microsoft Windows操作系统，Word ，Excel和PowerPoint的编辑，互联网和电子邮件的技术等等.他们也实施了在线自动划分等级。2. 系统架构 我们

47、基于Web的考试系统是一个基于DCOM技术的分布式协同系统。它有四个主要组成部分：考试准备制度系统，考试制度系统，考试监控系统和自动分级制度系统。u 考试准备系统是用来管理的储存，转让试验编号及附表的考验等问题。该系统的数据库的组成问题是一套可能的答案,比如问题的类型和其他中继问题。这们是收录的几个因素，如主题，关键字，复杂性和困难性等等。而其数据库对教师是开放的，并且允许他们新增的问题和答案以模板的形式。u 考试制度是为学生提供一个基于网络的测试界面接口的，它之所以被叫做所谓的WOES，是以为其中包括以下主要特点：客户端控制，时间控制，安全控制和自动安装控制。受益于DCOM技术，该系统可以安

48、装和更新本身的方便，它优越于C / S的框架。由于该系统是建立在网络上的，该系统的安全性问题面临着严峻的挑战。我们保证安全的加密技术，实时监测系统和数据传输加密。密码是用来验证学生鉴定前的测试。u 真正的实时监控系统是要求学生在电脑测试期间利用人的脸跟踪技术保证学生不离开电脑。系统对传递的试题数据进行传输加密，通过网络并以加密的形式传送到服务器。考试监控系统也是经理人考试制度，其中我们可以监控测试加工，进行试验编号统计，并收集答案等等。u 自动分级制度是设计的模糊匹配算法和宏观调控的编程技术，这是经验丰富的具有可变的问题类型。3. 基于Web在线考试系统3.1 考试制度目的作为一个普遍性的考试

49、制度，基本的电脑操作教育，它必须满足下列要求：1）存储一个合理的问题，必须要符合一般的考试大纲；2）有两种类型的考试界面。一个是模拟一种实用的接口，另一种是实际环境。第二个计划，因为实际的性质的计算机技能将给予学生更大的灵活性；3）一系列的问题类型，例如客观的问题，经营问题，设计问题，信息检索，测试组等等；4）一种安全和可靠的考试制度。3.2 WOES的组成基于Web的在线考试系统（WOES）是一个多层次的系统组成的Web服务器，数据库服务器， WOES的中间件服务器，WOES客户端模块和浏览器，如Internet Explorer 。在这个系统中，我们使用Internet Informati

50、on Server 4.0（IIS）的作为Web服务器，数据库服务器是Microsoft SQL Server 7.0的。核心的WOES是WOES中间件服务器和WOES的客户端模块，这是设计是据微软的DCOM标准。 DCOM是二进制COM对象的延伸拔节局域网，广域网和互联网，例如物体在不同的网络它可以约束。它是一种先进的网络协议用来配合基于COM的组成部分，这两个进程在不同的地点。该WOES中间件服务器是一个服务器端组件提供通信接口之间的WOES客户端和Web服务器或数据库服务器。该WOES客户端是一个客户端组件，就是所谓的由浏览器来控制用户端电脑，并提交或接收的信息从服务器的WOES。这种技术保证的灵活性和潜力，延长测试系统。此外，它允许访问本地文件，而在传统的系统，防止此类访问，即安全。 从DCOM中受益 ，从WOES中间件服务器在互联网上，WOES的客户可以下载或自动更新。他们也可以从一个客户端与其他WOES服务器沟通。该系统的行为像一个Agent社会，这是一个集中的代理人控制系统，不仅仅是WOES服务器。3.3 WOES的关键技术1）友好的用户界面我们使用浏览器作为我们的用户界面。该浏览器界面有一个统一和一致的用户界面。几乎每个人都能够熟练地使用它。因此，它可以消除分