Electronic Examinations e-exams Using Open Source Software

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1 Electronic Examinations e-exams Using Open Source Software L. FRAGIDIS, V. MARDIRIS, Ch. MIZAS, S. SIMEONIDIS and V. CHATZIS Information Management Department Technological Institute of Kavala GR Kavala GREECE Abstract. This paper presents the electronic application e-exams accessing a relational database through internet. The application is relied on open source software. MySQL is used as a relational database system for the database design. Scripting language TCL was preferred as the computer language used for the development of the application. The aim of the application is to provide an easier and efficient way carrying out electronic examinations for the Information Management Department of Technological Institute of Kavala. The users are separated to two different groups (academic staff and students). Each group is provided by a number of functionalities. A careful approach concerning the security of the application was considered taking into account that the software used is based on UNIX operating system. Key-Words: Internet Application, Open Source Software, Electronic Examinations, TCL, MySQL, Database 1. Introduction There is a vast amount of internet applications and electronic applications (e-applications) production today. Most of them are based on commercial software which, depending the version (academic, professional) of the tools used, obey certain limitations from the implementations point of view. Quite a few of those e-applications, derived from open source software or software free tools which anyone can download from the internet and use them with no significant cost. Open Source Software (OSS) can also be modified to fit the developer needs by changing the source code since the source code is provided with no cost too. The Electronic Examinations (e-exams) is a project set by Information Management Department in Technological Institute of Kavala, Greece. The e-exams has been developed as an internet based application which helps the examination process to be accomplished by an easier and faster way. Students are required to choose the right answers in a number of questions set by the lecturer of the examined module in a predetermined period of time. Four multiple choice answers are provided in each question. During the presentation of each question the student has the facility to skip the question without submitting an answer. Since all questions were presented and as long as time has not expired, the student can return to a question and submit a new answer. At the end of each examination session the student is informed for the percentage accomplished and along with it, the outcome of the examination that could be either pass or fail the examination. The e-exams application has been completely developed from open source software (OSS) tools. The OSS tools used are MySQL for the database part of the application, TCL/TK as the programming scripting language and HTML for the internet user interface programming. The Operating System in which the OSS tools operate is Unix Solaris 8 installed in a SUN Enterprise Server. MySQL database server for Unix is installed along with Active State Active TCL functioning with an Apache Web Server. The paper is organized as follows. A concise background on MySql along with a description of the database structure developed is provided in section 2. Section 3 includes the reason of scripting programming language Tcl was used. In section 4 a thorough description of the entire application and its features is given. Finally, conclusions are drawn in section MySQL and Database Architecture MySQL uses the Structured Query Language standard giving a great deal of control over a relational database system [3]. However, unlike most relational database systems, MySQL is

2 freely available, and because it operates on Unix systems, it integrates very well with scripting languages such as Tcl. 2.1 The structure of the Database The architecture of the E_Exams database evolved as the functionality of the database was growing. The resulting database structure is illustrated in figure1. In total there are ten separate tables, the eight of them are linked to the main table by using a different record number. Although it appears complicate, this architecture greatly simplifies the data insertion process into and also reporting sorted result out of, the database. Table Exams is the main table of the database and it holds all the appropriate information in relation to each examination carries out using the e-exams application. In almost each field of the table is stored the proper entry associated to another table of the database. Table Students holds all the personal details of each student in relation with the department. Table Modules provides more of the requisites information for all the modules comprising the educational program of the department. All the details concerning the academic staff are placed in table Academic_Staff. Table Quest_Categories consists all the categories of questions exists for each module. All questions for all modules that might be shown in an examination are stored in Questions table. The right answers for each question of the previous table are comprised in table Rightanswers. All possible wrong answers that may well displayed for each question are stored in Wronganswers table. The necessary information regarding the results of each student which takes part in the electronic examination is kept in table Results. Table Number is used to keep track the question number displayed for each student in every examination session. Table Exams_Session keeps all the examination sessions took place for each module. Each entry of table Exams is constituted of the field exams_id which is a unique integer number and primary key of the table as well. Following stud_id is an integer linked with table Student and field named aem which indicated the unique registration number of each student in the department. The surname, forename and fathers Fig.1: E_Exams Database Structure name along with the year of entry, the entry semester and the username of each student are located in table Students. Next integer field of table Exams is number_id associated with table Number where during the examination processes this table is used to indicate the current question each student is examined in. Question_id which is the subsequent field is referred to an integer number that is an entry number in table Questions

3 and provides the filename of the question, the category of the question belongs in, the module that is referenced to and the necessary time that has to be appointed to answer that particular question. The four following fields a, b, c, d are used to hold the four possible answers of each question and are linked with both Rightanswers and Wronganswers tables as shown in figure 1 because the positions where the right answer and the wrong answers are set, randomly. Table Rightanswers is constituted by four fields where the first one is a unique integer number, the second is the name of the file contains the right answer, the third is the mark assigned and the last one is the id of the question that the answers is referenced. Field named answer_id keeps an integer number which is the id of the submitted answer and is linked with both the above tables Rightanswers, Wronganswers for the reason that the given answer may well be right or wrong. The next field named mod_id is an integer indicating the module of the examination refers to and it is related with the table Modules where all the information about the specified module such as the name of the module exists. The field that follows is cat_id which is related with table Quest_Categories comprised by two integer fields apart from the primary key where the first one specifies the category and the second one the module each category belongs. Each examination session is indicated with the exam_id field associated with table Exams_Session where each session is reported initially here in relation with the examinable module. Field rightwrong takes Boolean values designating whether on not the given answer is right. Another Boolean field is answer which points out if the question was answered. The last field of table Exams is named locked which accepts Boolean values and when the value is set NO, no alterations can be made in the values of the fields in the specified record. Besides the relations almost all tables of the database have with the main table Exams, there exist more relations detached with the rest of them. Table Student is linked with filed aem apart from table Exams with the table Number with stud_aem. Both tables Rightanswers and Wronganswers are linked with the table Questions through the field quest_id in order each answer to correctly referenced to the proper question. Field mod_id again from table Questions is related with the same named field in table Quest_Categories since each question belongs to a category which is defined in the linked table. Moreover mod_id of table Quest_Categories is primarily associated with module_id of table Modules where all needed information concerning the module are present in that table. Table Result is also associated with the table Modules through the same field. In addition sess_id of table Results is linked with the field session_id of table Exams_Session in order the result of the examination to be assigned for the correct session. More information is provided by the designed database for students, modules and academic staff than the application needs. This information exists for further integration of the application. 3. Tcl and CGI Scripts Over the last few years, there has been a growing interest in various scripting languages [3]. One of the most open and successful ones is TCL. TCL stands for Tool Command Language and is a simple scripting language for controlling and extending applications. It provides generic programming facilities that are useful for a variety of applications, such as variables, loops and procedures. Furthermore, Tcl is embeddable: its interpreter is implemented as a library of C procedures that can be easily incorporated into applications, where each application can extend the core Tcl features with additional commands specific to that application [2]. As a scripting language, Tcl is similar to other UNIX shell languages such as the Bourne Shell, the C Shell, the Korn Shell, and Perl. Shell programs permits the execution of other programs and provides enough programmability (variables, control flow, procedures) building up complex scripts that assemble existing programs into a new tool tailored to developers needs. Shells are wonderful for automating routine chores [1]. An additional benefit of using a scripting language such as Tcl, in conjunction with a relational database such as MySQL, is the notable compatibility of these tools. MySQL offers the advantage of being manipulated and queried by using Tcl. The CGI scripts that makes the e- Exams editable from the WWW (World Wide Web) have been developed. Essentially the scripts

4 translates the user s input submitted by an HTML form, into an SQL query of the MySQL database, which then reports the results back to the user s WWW browser. A schematic approach is illustrated in figure 2. Fig.2: Accessing the database 3.1 Scripts Analysis The first script of the application is the login script which is responsible to verify that the user tries to login the application is a valid user. The Tcl script through the tcl shell executes an internal UNIX command in order to confirm that the given username and password exists on the UNIX Operating System. Taking into account that the access has granted from the previous script depending on the users preferences the appropriate scripts takes over. In case the user logged in is a member of the academic staff have two options. The first one is to look into past examination sessions occurred and the second one to open a new examination session. Since the second option have been chosen the part of the next script that displays a list of the available modules that can be electronically examined are provided. In the following script the time of the examinations session needs to be set. At the time the user clicks the submit button a process which s owner is the logged in user, starts indicating that a new examination session for the selected module has just opened. If the first option was selected the part of the next script is executed. This provides a new web page which is constitutes by two selections with respect to the examinable modules and the attained sessions. Since the appropriate selection is made the proper queries to the database are established in order a web page with the results to be generated. When a student logged in, a web page displays in which the student can select the desired module is going to be examined. Since a module is selected the script that brings the first question and the four possible answers from the Exams database is executed. Before the query for the first question is made an earlier query is made concerning the categories of questions exist for the selected module. Since the number of the categories is known, one of them is selected randomly from the script. The displayed question is randomly selected from the amount of the available questions according to the chosen category. There are three wrong answers displayed concerning the question that randomly queried from the database. The positions of those three wrong answers along with the right one is not pre determined and all answers are randomly positioned. Every time an answer is submitted or skipped the same procedure as described previously is repeated in the next script for each question making sure that the same questions will not be displayed again. While the last question is answered a script generating a report of the answered and skipped questions is executed. The student has the ability to choose a question that desires to resubmit an answer. The script that follows makes the necessary queries in order the selected question along with the answers displayed to be redisplayed exactly the same. Since an answer is submitted the proper updates are made in the database. In case the available time expires or the termination button was clicked a script that locks all the appropriate records in the database is executed. Additionally the obtained percentage is being calculated performing the appropriate queries and will be displayed accompanied by the

5 outcome of the examination. A more detailed description is given in the next section. 4. Description of Application This section describes the user interface, with emphasis on the features provided by the e-exams application. Two groups of users have access to it. The first group is the academic staff of the department. The second group is composed by the students of the department. Each group has different functionalities with respect to the application. In order an examination of a module to take place, the proper lecturer should open an examination session and the students should answer to the given questions. 4.1 Academic Staff Functionality The first web page of the application is the login page. Since a member of the academic staff group passes the login page, a web page is presented with the proper electronic examinable modules for the logged in user. The next step after a module is selected, the maximum time has to be declared that each student will be granted to answer the questions that will follow. The number of questions are going to be presented depends on the maximum time set since each question has its own maximum answer time. While all the students finished with the examination process the user should close the examination session in order no other student has the permission to restart the examination. Another feature provided by e-exams application to the academic staff group of users is the generation of a report for the desired examination session. Initially the user has the ability to select one of the appointed modules and the application will provide a list of the available examination session occurred in the time being. Since an examination session is selected a report is generated presenting the results of the examination as illustrated in figure 3. Apart from the personal details of each student which has participated in the examination like surname, forename and registration number, the report points out the percentage gained and the outcome of the examination for each one of them. Moreover an analytical presentation of all the given answers along with the available answers in each question, indicating the right one, can be Fig.3: Examination Session Report offered by choosing one of the displayed students surname. Presumably the lecturer is capable of exploring all the examination sessions occurred for each student. 4.2 Students Functionality All students of the department have their personal username and password for the e-exams application. Since a student has logged in successfully, a choice concerning the examinable module has to be made. Selecting one of the available modules and given that an examination session has been opened from the appropriate lecturer, the first question of the examination is presented as given in figure 4. Besides, the first question the web page displays is constituted by an inverse timer counting down the remaining time of the examination. Four possible answers are provided for each question and the student can either select one of them and submit an answer or skip the displayed question or terminate the examination. Each time the student submits an Fig. 4: First Question answer or skips a question the application proceeds bringing up the next question. By the time the student goes through all questions a

6 report is displayed providing information regarding the number of questions answered and which questions were skipped as shown in figure 5. Fig.5: Student Examination Report The student can either terminate the examination process by pushing the Terminate button or select which question desires to be redisplayed in order to submit a new answer. This procedure can carry on as long as there is enough time given by the countdown timer. In case the time expires or the Terminate button is clicked in any stage of the examination procedure a web page is displayed informing the student for the percentage gained and the examinations results. 5. Conclusions e-exams is an internet application that is experientially operative in the Information Management Department in Technological Institute of Kavala, Greece. The application speeds up the correction process of the examinations. It also provides an easier and restrained manner for the academic staff to access the results of each examination session along with a detailed presentation of the answers supplied in every question for each student. Each lecturer is responsible and has full control of every examination carrying out for the modules that is in charge of. The e-exams application is built-up using only open source software and that gives the ability of an easier application growth. The scripts that have been created can quite simply enriched to meet the augmentative user needs. There are certain observation been made from the users of the application and it is considered to be enclosed to the next version of e-exams. A further extension of the application would be the mark of each student attained in each examination accomplished by e-exams application to be passed to the application working in the secretary office of the department. Therefore the secretarial staff will not be obliged to insert each mark by hand. This will lead to a much more useful internet application and makes a significant part of the educational procedure more effective. Acknowledgement This work was partially supported by the Dilatation of Higher Education in Technological Institute of Kavala project and Informatics Studies Support project of Operational Program Education and Initial Vocational Training (EPEAEK II). References: [1] Brent Welch, Practical Programming in Tcl and Tk, Prentice Hall, 1995 [2] John K. Ousterhout, Tcl and the Tk Toolkit, Addison-Wesley, 1993 [3] MySQL Reference Manual, TcX AB, Detron HB and MySQL Finland AB, 2000 [4] John K. Ousterhout, Tcl: An Embeddable Command Language, Proceedings of the Winter 1990 USENIX Conference, Washington, D.C., USA, pp [5] Robin Burk, UNIX Unleashed, Sama, Third Edition, 1998 [6] Main Tcl Developer Exchange Site [7] MySQL Open Source Database Site [8] Thomas Powell, HTML & XHTML: The Complete Reference, Fourth Edition, 2003