e-tutor - An Approach for Integrated e-learning Solution

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1 e-tutor - An Approach for Integrated e-learning Solution Pradipta Biswas 1 and S. K. Ghosh 2 1 Computer Laboratory, University of Cambridge, Cambridge CB3 0FD, England pb400@cam.ac.uk 2 School of Information Technology, Indian Institute of Technology, Kharagpur ,India skg@sit.iitkgp.ernet.in Abstract With substantial growth in multimedia technology and increasing availability of computer systems, there is thrust towards computer-based training, which uses interactive text, audio, visuals and animation, in a self-paced mode. End-users (i.e., students ) satisfaction levels have seen a marked improvement with the use of these modern methods of education technology. The present paper proposes a framework for integrated e-learning environment. Our system has advanced e- learning features like provision for integrating multiple simulators for different subjects, integrated student performance evaluation system etc. The novelty of our system lies in the creation of an integrated framework that will cover all the aspects of teaching activities starting from classroom lecture, laboratory work and final evaluation. An operational prototype of the system is used in a limited way in a premier engineering institute and the result is quite encouraging to use the system for a longer duration. Keywords: e-learning, Education Technology, Simulator 1 Introduction There is an increasing use of computer as a teaching tool, especially due to availability of a plethora of interactive computer based teaching packages that can supplement classroom lectures. However, for some subjects, laboratory work is an integral part of classroom lectures the subject cannot be assimilated without the laboratory work. Realizing the importance of the hand on experiments as part of a course, recent researches have focused on integrating simulator or software tool with traditional onedimensional computer based teaching tools. We present a few examples of such systems in the next section. Statutor software [1] is designed to simplify the learning and teaching of statistical concepts, especially those related to sampling distributions based on sampling from a population. Another such initiative is Pegasus [2], which helps students to visualize laboratory work with a 3-phase induction motor. Besides the education technology departments of Universities, some commercial products are also available to facilitate learning of basic principles. DENFORD Machines & Systems Company has developed

2 CNC Desk-Top Tutor for understanding the basic principles and developing practical skills in Computer Numerical Control (CNC) [3]. Network for Inclusive Distance Education [4] has developed interactive learning products like Digital Frog International, Snowbird software etc. They have taken a novel approach to spread the learning in an interactive way to disabled students also. One such software is A Digital Field Trip to the Rainforest which offers self-voicing for users who have visual disabilities. Millard [5] presents Interactive Learning Modules for Electrical Engineering students which provide interactive and animated simulations, problem sessions and online guidance. Halvorsrud and colleagues[6] introduce the concepts of Virtual Reality to design a collaborative environment for easy understanding of molecular biology, DNA structure etc. for secondary standard students. Woolf [7] describes technical details of providing interactivity (about use of Flash Animation or JAVA Applets) and conceptual detail of building a learning tool has been given. Shin and colleagues [8] discusse a web based virtual laboratory system that pioneers an approach of using VRML and XML in the building of simulation and animation. An intelligent multimedia tutoring system has been proposed in [9] for Cardiac Diseases. Most of these existing e-learning systems are targeted towards very specific and specialized areas (e.g. 3-Phase induction motor or Computer Numerical Control etc). The term Virtual Laboratory has been used at [8]. The high level aim of our project is same as Shin [8] but our approach is more scalable. The present work aims at developing a framework that consists of simulators for more than one subject (the subjects may vary from Communication Engineering to basic subjects, like Physics, Chemistry etc) and on-line teaching and evaluation modules. The simulators are so designed that they will help students to understand the basic principles of a subject through multimedia aids. Most of the multimedia tools used in e-learning or web learning packages are high end animations (JAVA Applet or Flash files) rather than a simulator in true sense. Our simulators provide more freedom to the user in terms of designing an experiment. The novelty of our approach lies in its integration and interaction features - a single package enables users to upload and read lecture slides, to simulate practical demonstrations for different subjects and to take evaluation using an interactive evaluation system. The paper is organized as follows. In section 2 an operational overview of our system is presented. Following the operational overview the present status of the system is described in section 3. We have pointed out the novelty of the system in section 4 followed by conclusion. 2 Operational Overview Our system operates in three phases to construct and properly use a student model. These phases are 1. Initialization Phase 2. Running Phase 3. Assessment Phase

3 These system phases conform to the regular course calendar. The initialization phase takes place before start of a course. The running phase runs with the course. After the end of the course, the students and teachers performances are evaluated in the assessment phase. The initialization phase mainly concerns with database fill up with curriculum details and demographic information. A course is broken up into a number of subjects. Each subject is further classified into chapters or topics and a topic is broken up into some concepts. As for example a secondary level science course can be divided into subjects like physics, chemistry, biological sciences and mathematics. Physics can be disintegrated into topics like optics, magnetism, mechanics etc. The topic mechanics includes concepts like free body diagram, inclined plane, momentum etc. When this ontology will be defined for several subjects, it is possible to define surmise relationships among the concepts and develop a knowledge space for a student [10]. In our system, each topic, concept and question is given a difficulty index. Questions are associated with an expected answer time also. These difficulty indices are used for assessment of the student. Initially when the system is installed for the first time, the difficulty indices are assigned a value based on an assessment made by experienced teachers. In the running phase, the teacher can periodically evaluate the class performance by designing online examinations or quiz sessions. These examinations or quiz can be designed using the existing question-answers within the database or by inserting new questions and answers. Even the course instructor can add new topics or concepts also during this running phase. Short-term assessment can also be carried out by manually analyzing the points scored by the students during an examination. After the end of the course, the final assessment can be carried out. The final assessment will not only consider the immediate performance of a student in a single course, but also takes care of historical data available about the students, teachers and subjects. 3 Present Status of the System Currently an operational prototype of the system is implemented on a multimediaenabled based Pentium-IV system (with standard configuration and Windows operating system). The successful implementation of the system largely depends on the proper planning of the course in terms of lecture modules, experiment sets and evaluation plan for the particular domain. Present implementation includes development of a virtual classroom module, online examination module and two simulators for communication engineering and system programming. In the following sections a brief outline of the system will be presented. 3.1 Virtual Classroom Module The virtual classroom module aims to simulate basic classroom activities within a computer screen. In the virtual classroom of our system, there will be provision to

4 present a video lecture and (or) a slideshow synchronously. The upload module can be used to upload lecture slide or video lecture. There will be a writing pad in the screen where students can take notes and can store for future reference. 3.2 Simulator Modules The system is designed in a way that third party simulators can also be easily integrated with the system. Currently the system is integrated with two simulators-one for communication engineering and the other for systems programming. Both of these simulators help to visualize complex operations to students. The next two sections will present an overview of the simulators with examples of their usage Simulator for Communication Engineering The simulator for Communication Engineering can be used to simulate basic signal processing operations like addition, subtraction, integration etc. It can also simulate modulation techniques like Amplitude Modulation, Frequency Modulation, Delta Modulation, QPSK, GMSK etc. Each of these signal operations can be demonstrated with all intermediate steps. As an example of its usage, a modulation operation viz. Pulse Width Modulation (PWM) is demonstrated in the next section Demonstration of Pulse-Width Modulation The process starts by drawing a Baseband signal. Fig. 1 shows a Sine wave and its frequency response. In Fig. 2 the PWM Waveform (in blue color) is shown. Fig. 3 gives the frequency response of the PWM waveform (in gray color). Then the PWM waveform is demodulated. The Baseband signal, the demodulated signal (in yellow color) and their correlation are shown in Fig. 4. Fig. 5 shows the modulating, modulated and demodulated waveforms simultaneously. Finally the frequency responses are drawn again in Fig. 6. It has been shown the frequency response of the modulating and demodulated waves overlap, as expected Simulator for Systems Programming The simulator for system programming is developed to illustrate students the sequence of actions occurred inside a computer for executing a program. Most practical courses on system programming start with 8085-microprocessor programming. The simulator presents a step-by-step analysis of an 8085 assembly language program execution. It consists of four modules viz. Editor, Assembler, Loader and Debugger. The editor instructs the user to write an assembly language program or importing a previously written program. The assembler takes a starting memory address and run a two-pass assembler program. The user can see Symbol Table or the Error Table from the assembler. The loader simply loads the object code. Optionally, the user can also relocate the object code using the Loader. Finally the debugger executes the object code. The user can also step over through the object code. After execution, the

5 debugger allows the user to see any memory location, register or system flags. In the next section, the system is explained with an 8085 Multiplication program. Fig 1. Baseband signal and its frequency Response used in the demonstration of PWM Fig 4. Baseband Signal, Demodulated Signal and their Correlation Fig 2. Baseband signal and PWM Waveform Fig 5. Baseband Signal, PWM Waveform and Demodulated Wave Fig 3. PWM Waveform and its Frequency Response Fig 6. Baseband Signal, PWM Waveform, Demodulated Wave and their Frequency Responses The 8085multiplication program is shown in Fig. 7. The assembler produces the object code shown in Fig. 8. Fig. 9 shows the relocation operation by the Loader after

6 relocating the program from address E000 to The red circles in Fig. 9 show the code modifications due to relocation. Finally the Debugger executes the program. The register values and Flag Values at each step of execution are shown in Fig Online Examination Module The online examination module takes a set of questions and answers as input. Optionally the question set can be divided into 2 two 8 sections. The questions in each question set are presented sequentially. There is a mechanism to store response time and given answer of each question. At any stage of examination, a student is free to see his status. In the status window, all of the questions of the present section with the given answers and number of unanswered questions will be shown. The detail of the evaluation process is discussed in a separate paper [11]. Fig. 7. Source Code of a Multiplication Program Fig. 8. Object Code of the Multiplication Program 4 Novelty of the System Integrated Approach: Our system is not merely an e-learning package for a particular subject, rather it can be served as a virtual college where course instructors can upload lectures, monitor the progress of students and evaluate them. Besides going through the lecture slides, students can also run simulations of laboratory works. The system will

7 be particularly useful for students of under-developed areas where it is not always possible to construct a high-end laboratory with skilled instructors. Fig. 9. Object Code after Relocation from E000 to 9000 address Fig. 10. Register Content and Flag contents at each step of execution and Memory Content after execution Modular Design: We developed the system in a modular fashion such as any module of the system can be used independently from the others. So during deployment, any module of the system can be replaced by a more customized one or new modules (e.g. simulators for different subjects). Intelligent Evaluation: The evaluation module of the system [11] is particularly important. It consists of a database as well as a data warehouse for storing information about teaching and learning at a very detailed level. The data warehouse can be used to calculate performance metrics for any possible groups of students, teachers and subjects. As for example, we can calculate metrics very efficiently indicating

8 performance of mid-worker student in Optics, performance improvement of students during first half of a course etc. In a decision-making scenario, these metrics may help in providing enough insight into the assimilation capability of students and teaching capability of teachers. Once measured properly for adequate length of time, these metrics can also be customized to provide other useful utilities like developing a student model, measuring utility of a course modification, quantifying institutional performance etc. 5 Conclusions The present paper merges e-teaching with e-laboratory thus making e-learning more effective. The teaching tool will be an interactive audiovisual system, which will break up the course in a series of lectures, computerized practice sessions and assignments. The integrated simulator can be used to visualize the operational environment without a practical laboratory set up. The framework is accompanied by a personalized student evaluation module that can provide many other useful information like utility of a course modification, institutional performance etc. An operational prototype of the system is used in a limited way in a premier engineering institute and we hope the system will be particularly useful for students of under-developed areas where it is not always possible to construct a high-end laboratory with skilled instructors. References 1. Wolfe Robert A. (1991), Statutor Version1.23 A computer-based teaching tool for statistical concepts.available: statutor/statu123.readme, Accessed on: 29th March Avouris N.M. et. al.(2000), Development and evaluation of a computer-based laboratory teaching tool Available at: j21_avouris-tselios-tatakis-00.pdf, Accessed on: 29th March Morozov E(1996), Implementation of computer based teaching Systems for professional training in Computer aided engineering in Proceedings of the ICDED Interactive Learning Tools; Network for Inclusive Distance Education(2006); Available at: Accessed on: 31st March Millard, D.L.(2000), Interactive Learning Module for Electrical Engineering Education, In Proceedings of the Electronic Components and Technology Conference, Pages: Halvorsrud R. et. al. (2004), Designing a Collaborative Virtual Environment for Introducing Pupils to Complex Subject Matter In Proceedings of the third Nordic conference on Human-computer interaction October Woolf B. P.(1996), Intelligent Multimedia Tutoring System; Communication of the ACM, April 1996 Vol. 39, No Shin D., Yoon E., Lee K., Lee E.(2002), A Web based interactive virtual laboratory system for unit opeartions and process systems engineering education: issues, design and implementation, Computers & Chemical Engineering, Volume 26, Issue 2, 15 February 2002, Pages Chen C., Lee,H. Chen Y.(2005), Personalized e-learning system using Item Response Theory, Computers & Education, Volume 44, Issue 3, April 2005, Pages Dietrich A. et. al., (2006) Current Trends in elearning based on Knowledge Space Theory and Cognitive Psychology Available at: ~ac18008a af0348c d887feb,, Accessed on: 15 th July Biswas P., Ghosh S.K. (2005), An Universal Assessment Methodology for Evaluating Students' and Teachers' Performance in an Academic Institute, Proceedings of International Conference on Cognitive Systems (ICCS 05), Available at : Accessed on 24 th July 2007