Global J. of Engng. Educ., Vol.I,
No.2 Printed in Australia |
Copyright 1997 UICEE
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Electrical Engineering Education - a Complex Approach* | |||
Zenon J. Pudlowski
Faculty of Engineering, Monash University, Clayton, Melbourne, VIC 3168, Australia |
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TABLE OF CONTENTS
The technological advances of recent years have encouraged engineering education institutions to search for more advanced and efficient teaching methods through the use of computer and multimedia technologies. More undergraduate curricula now include the use of computers in teaching programmes. The availability of relatively inexpensive computer hardware has further encouraged educators to consider alternative methods of information dissemination and more advanced approaches and techniques to teaching undergraduate students.
Recent research into the application of computers to engineering education indicates that many academics consider the use of computers in teaching practice as a worthwhile alternative to traditional teaching methods, particularly in such a demanding discipline as electrical and electronic engineering. For instance, over 200 separate software packages are used for teaching purposes within the Faculty of Engineering at Monash University alone, with more than 50 of these developed by staff at Monash University [1].
The UNESCO Supported International Centre for Engineering Education (USICEE) was established in 1993 at Monash University on the recommendation of the then UNESCO Steering Committee on Human Resources Development for Technical Industry Stimulation. It commenced its operation in January 1994 under the directorship of the author. The Electrical Engineering Education Research Group (EEERG) became an integral part of the USICEE [2]. In recognition by UNESCO of the Centre’s achievements, it was awarded full UNESCO status in June 1997, dropping the symbolic Supported from its name and becoming the UICEE.
The UICEE is the world’s first and only centre for engineering education established under the auspices of UNESCO. It is a unique development which has been endorsed by a number of academic institutions and professional organisations worldwide. The establishment of the Centre is widely regarded as the most important undertaking in the globalisation of engineering education. The role and importance of the UICEE have already received international recognition.
A principle objective of the Centre is to fulfil the vital role of clearinghouse for engineering education equipment, courseware and software from developed to developing countries. The Centre is seen as part of the north-south dialogue, with Australia, in this instance, standing as a country of the north located in the south, eager to assist in developing engineering and technology education in less developed countries.
The UICEE has established a number of research interest groups, with members of these groups interacting via the Internet, in order to facilitate research and promote collaboration and best practice in engineering education [3].
The EEERG’s zenith was in 1992 when the Group consisted of six staff members (three academics), seven postgraduate students and a number of local and international visitors and associates. At that stage it was a fully developed entity well known locally and internationally with many interesting research activities and publications to its credit.
Although the EEERG has lost its permanent members due to the impossibility of relocating them from Sydney to Melbourne, it has continued its research and publication activities. Most of the EEERG postgraduate students have already completed their projects. In an era of electronic communication, several former members of the EEERG have decided to continue their close association with the EEERG despite their physical separation from the UICEE.
It should be mentioned that, as well as research and development efforts, the UICEE has organised a number of research seminars for academic staff for their continuing educational development. Topics closely related to Computer-Aided Engineering Education (CAEE) have included:
Hypermedia - student-centred educational software.
The UICEE has established several electronic mailing lists to facilitate the transfer of information throughout the national and international engineering education communities. These mailing lists are:
Other mailing lists for interest groups are envisaged to be set up in the near future. Access to the mailing list is free to local and international academics.
The role of the UICEE in developing CAEE
Although the Centre is still in its development stage, it has already vigorously pursued many activities for the benefit of the Faculty of Engineering in Monash University and the national and international engineering education communities. Many local and international engineering academics and industry staff are actively involved with the Centre.
The UICEE endeavours to provide the necessary resources for a wide range of activities, including research into the effective use of equipment, courseware and software, as well as effective methodology utilised in engineering education. In this regard, the Centre’s priority is to pursue research and development activities in the application of computers and computer technology to engineering education. Several projects have continued and new projects are currently being devised and implemented. Most recently it has established a programme to investigate the effectiveness of a hypermedia knowledge base for comprehensive self-study procedures using developments in electronic technology [4].
As noted earlier, results of the Survey into Computer-Aided Instruction carried out by the UICEE indicate that the use of software for teaching engineering is strongly supported by Faculty members, with 70% using these techniques regularly. The use of software packages in teaching has flourished, with staff actively involved in the development of software.
The objective of this paper is however to report on a number of activities carried out by the EEERG and other members of the UICEE.
Teaching the Concepts of Electromagnetism
Students find it particularly difficult to comprehend the physical phenomena which occur in electromechanical devices and systems; educators also find them fairly awkard to deal with. The situation is further complicated when it comes to dealing with basic concepts and principles of energy conversion, which involve a thorough understanding of electric and magnetic fields. To be able to consider and skilfully investigate the behaviour of such devices and systems one must not only be able to demonstrate the knowledge of physical phenomena, but must also be able to perform extremely complex mathematical operations and calculations.
To facilitate understanding, a new experimental setup (incoroporating a single-phase electromechanical device consisting of a single-phase excitation coil in series with a capacitor, and an iron bar moving in the coil) was recently designed and developed [5]. This construction, it has been found, is useful for demonstrating the behaviour of electromechanical devices, with students being exposed to a variety of basic concepts, ideas and physical phenomena and their application in such devices and systems. A number of topics concerning electrical engineering can be identified by using this procedure:
The entire experimental procedure is based upon a single-phase electromechanical device which may be equipped with a spring, or which can operate with feedback. The basic arrangement in both cases is the same, but the circuit setup is altered slightly when the latter is used. The main objective of this procedure is to study the behaviour of an electromechanical system under different supply and load conditions. The educational principle of this design is that the material taught integrates important concepts across the whole spectrum of electrical engineering with recent and advanced experimental techniques.
The system can be used to examine steady-state and transient conditions. Steady-state conditions appear in the system when the bar is not movable, that is, the behaviour of the system at steady-state conditions is investigated for certain fixed positions of the bar. Three specific cases then may be distinguished and subsequently examined:
This procedure, which integrates several areas of electrical and mechanical engineering, appears to make the study of electromechanical devices more interesting for students, at the same time that it imparts knowledge of a number of basic concepts, principles and phenomena which occur in electromechanical devices and systems. Work is being carried out on the conversion of this procedure to computer software.
A substantial part of this research and development work was recently undertaken by a student from Technische Hochschule Darmstadt in the Federal Republic of Germany. This is an excellent example of the involvement of undergraduate final-year students in research into the application of computers to engineering education. The student’s semester-long visit to the EEERG was for the purpose of undertaking a final-year project involving the development of simulation software for a linear self-oscillating reluctance motor. The objective of the project was the design and production of a tool which could be used to demonstrate the steady-state behaviour of this oscillator.
The resulting software demonstrates the behaviour of the oscillator by showing the bar’s displacement, the variation of the coil’s inductance and current, the rms values of the current, magnetic force and speed of the bar in accordance with the chosen supply voltage and its frequency. Figure 1 presents a sample computer screen of the simulation programme.
Figure 1: A sample screen of the simulation software program for a linear self-reluctance induction motor.
A logic gate and basic digital systems simulator has been designed and developed by K. Shuwayhat, under the supervision of the author, as part of a postgraduate project [6]. This digital simulation system makes extensive use of computer graphics to simulate digital logic gates and fundamental digital systems, and is written in an object oriented form. The product of the programme is a colour graphical display which shows the circuit components, connection and text information.
The simulator consists of sixteen programmes designed to introduce the digital circuit and the logic gate operational concept to the student through use of the analogy of a simple dc switching operation.
There are two standard screen layouts used in the simulator. The first uses the basic dc electrical circuit, including electric switches, as an analogy through which to introduce the concept of a simple logic gate. Figure 2 shows a two input OR gate as an example of the first screen layout.
Figure 2: A sample screen of the first circuit layout.
The graphical symbol (icon) of the gate is displayed on the screen together with its input and output terminals. The status of the switches in the electrical circuit can be changed by clicking on a mouse. The logic status of the individual inputs and outputs of the gate is automatically displayed in a square associated with an individual terminal of the gate. A simulated electric lamp then indicates the status of the output of the gate.
The function of the circuit is also explained in a short written statement together with relevant questions or commands. A truth table indicates the logic status of the gate.
The second standard screen layout includes a multitude of individual logic gates creating a logic circuit with multiple inputs and outputs. An example of this arrangement is shown in Figure 3. The logic statuses of individual inputs and outputs of the gates are displayed in the same way. Electric lamps then also indicate the input and output statuses of the logic circuit. Truth tables give the logic status of an individual section of the circuit or the entire circuit. Written statements give basic information concerning the circuit and lead the student through the exercise.
Figure 3: A NOT-NAND-OR system as an example of the second circuit layout.
The screen layout - a number of simultaneous open windows - eases the student training exercise by retaining information and exercises on screen so that the student does not need to be reintroduced to each exercise after he or she has completed the previous one. The layout and format of requirements is repeated in all practical exercises.
The system is designed in four parts. Start up, with two introductory stages, explains the circuit components and introduces the method of applying fundamental circuit principles to digital circuits. It then shows an equivalent digital circuit which explains the principle of operation of the logic gate.
The second part is the practical educational course which, in the same manner, shows how a dc switching circuit can be arranged to perform certain logic switching sequences to explain the fundamental operation of AND, OR, NOT, NOR and NAND gates.
The third part is a practice session in which pre-designed exercises consist of logic gates connected in a circuit to perform a certain task. The design of the third part of the exercise leads the student from using a few combined simple gates to working with a large complex circuit.
Part four consists of four complex gates, the Decoder, Multiplexer, Exclusive-OR and Exclusive-NOR.
The system is designed to provide the student with an interactive simulation of real digital circuits and systems, thereby providing contact with the real world without the necessity of using laboratory equipment. Practice with the simulation process on a colour graphic screen largely enhances the visualisation process, thus increasing the degree of transfer of information.
The individual parts of the programme exhibit similarity in presentation and start with a simple introductory session for logic gates and their analogy. The whole programme is designed to establish a high level of interaction between the user and the training system.
The programme arranges the gates together and then requests the user to interact with the simulator to reach the output requested. The user can then see how a simple gate behaves and how a number of simple gates can be arranged together to produce a digital system. The system demonstrates how complex gates can be constructed from simple gates and provides the user with an understanding of how such systems behave.
This software emphasises the very early stage of logic circuit learning. The concepts and ideas behind such logic circuits and the way in which they can be taught are included in most of the available text books. The software however offers a new and interactive way of teaching logic gates and systems with the aid of a personal computer.
SEMDEM — Computer-Assisted Education Programme
The physics, and indeed the behaviour of semiconductor devices, have been taught for many years. As with electromechanical devices and systems, both lecturer and student experience many difficulties during the teaching/learning process of such devices; the theory of semiconductors is hard for students to comprehend due to the complexity of the physical phenomena taking place in such devices and the sophisticated mathematical expressions used to describe their behaviour. Often the lecturer, on the other hand, is inappropriately prepared to teach such a difficult subject. Moreover, he or she is ill-equipped with the necessary tools to illustrate the principles of operation of such electronic devices. This is where computer-based education programmes can assist.
An educational software programme for the analysis of the behaviour of various power semiconductor devices (SEMDEM) has been developed as a result of co-operation between the EEERG and the Institute of Electronics at the Technical University of Lodz, Poland [7]. A substantial part of this development was accomplished by Dr Marek Turowski, in collaboration with the author, when Dr Turowski was a visiting scholar within the EEERG at The University of Sydney between September 1992 and September 1993.
The SEMDEM computer software programme assists the user to examine and analyse the behaviour of bipolar semiconductor devices. Semiconductor structures are simulated in an interactive way; both static and dynamic conditions may be analysed during the operation of the devices. The behaviour of several physical quantities, such as an electric potential, the electron and hole density and the electrical current density inside the semiconductor devices, can be examined. Relevant graphs are plotted in individual windows on the computer screen. A sample screen of the SEMDEM programme is shown in Figure 4.
Figure 4: A sample screen of the SEMDEM program.
The following simulations of bipolar semiconductor devices can be performed when using the SEMDEM software programme:
The simulations are based on a numerical solution of the set of differential equations (including Poisson’s equation, transport equations for electrons and holes, and continuity equations) which describe the semiconductor structures with full models of physical parameters.
The programme can be used to examine and analyse the standard diode and thyristors. The following values of parameters can be changed in an interactive way when analysing the static and dynamic behaviour of the devices:
The programme can be implemented on an IBM compatible PC 386 (or higher) computer with a maths coprocessor and with a VGA colour graphics monitor.
The SEMDEM programme is an extremely powerful tool for electrical and electronic engineering education where the behaviour of semiconductor devices is to be considered. The ease with which the programme can be operated, the educational approach to the subject matter, as well as a multitude of features, make this programme an excellent aid in teaching electrical and electronic engineering.
A book titled Computers in Electrical Engineering Education - Research, Development and Application has been produced as a result of the successful research and development activities carried out by members of the EEERG between 1988 and 1994 [8]. The release of this book, a first publication under the Monash Engineering Education Series, began a new era in the activities of the UICEE, adding a new dimension to Australian engineering education by creating a source of information on research and development activities in engineering and technology education. Moreover, this series opens up tremendous opportunities for engineering educators to share their achievements with local and international colleagues.
The idea of establishing this series arises from the Centre’s mission to stimulate research and development activities in engineering education, and to facilitate the transfer of information, expertise and research results on engineering education. This series is open to all academics involved in engineering education research, and aims to facilitate a dialogue between engineering educators worldwide.
Computers in Electrical Engineering Education - Research, Development and Application consists of ten chapters and presents recent achievements in the application of computers and computer technology to electrical engineering education. Most of the chapters describe activities which were carried out for the award of a university degree.
Chapter 1 presents a comprehensive overview of the activities of members and associates of the EEERG. Issues of importance when developing computer-based authoring programmes are discussed in Chapter 2. Following chapters describe specific research and development activities in the design and implementation of computer-based teaching programmes for electrical engineering education. The nature and development of a computer-based Aptitude Test for Electrical Engineering is presented in Chapter 3. The software has been used successfully in over forty academic institutions worldwide.
Chapters 4 and 5 present two research and development projects in computer-based authoring systems. The two developments demonstrate different approaches to the design process of such computer programmes. Both chapters present research projects carried out for the degree of Master of Engineering (Research) completed successfully in 1993.
The application of computers to electrical machines and apparatus is discussed in Chapter 6. In particular, the investigation and control of an induction motor with the aid of a personal computer is demonstrated. This was a final year project which led to the award of the degree of Bachelor of Engineering. Chapter 7 presents research work which was a continuation and expansion of the work initiated in the undergraduate project described in Chapter 6. Particular emphasis was placed on the development of a system for the undergraduate teaching laboratory. A set of laboratory procedures used when experimenting with electrical machines was designed and implemented under this project. The work led to the award of Master of Engineering (Research).
Chapter 8 shows the development of a simulation programme used in the teaching of digital gates and systems. The project was part of work leading to the award of Master of Engineering Studies. Chapter 9 presents a simulation programme for the analysis of the behaviour of a single-phase linear self-oscillating electromechanical device, developed to illustrate the complexity of electrical power engineering systems. The idea for this simulator came from engineering research carried out with the device. Substantial parts of this work formed a final year project carried out by a student from Technische Hochschule Darmstadt, subsequently awarded an electrical engineering degree in Germany in 1993.
Finally a simulator used for the investigation of the behaviour of power semiconductor devices is discussed in Chapter 10. The design process of this programme, including its pedagogical aspects and features, was carried out in close collaboration with the EEERG Director. A short description of the work included in the last three chapters is mentioned in this paper.
The entire book is a compendium of information on the application of computers to electrical engineering education and should demonstrate to the reader a variety of challenges and opportunities coming from the use of computers in teaching practice. Another objective of this book is to demonstrate how undergraduate and postgraduate students can be engaged in engineering education research. Indeed the authors hope that the book will stimulate further research and development activities in this field.
The role of computers in engineering education
A training course for academic teachers on The Application of Computer-Assisted Training Programmes in Engineering Education, sponsored by UNESCO, has been developed and implemented by the UICEE and was published in book form in 1996 [9]. Several academics from various Monash University units prepared session notes and conducted the course.
The objective of this course is to enhance the understanding of young engineering academics of the role of computers in engineering education. The more specific objectives of the course are:
Twelve academics from countries in South-East Asia and the Pacific region were invited to the course, which was carried out for the first time between 7 and 11 November 1994. Another UNESCO sponsored course was run at Monash University between 10 and 18 July 1997. Participants of the courses received education in the fundamental principles of the teaching/learning process, the development of computer-assisted teaching programmes and hands-on training in the management of a range of engineering education computer software.
The course consists of ten units which are largely stand-alone. The units and the duration of the training are shown in Table 1.
A survey of the outcomes of the course was carried out on completion of the course. The participants were invited to complete an evaluation questionnaire developed by the UICEE to gauge their reactions to the course material, lecture presentations and facilities, and to identify any need for future collaboration with the UICEE to help establish their own courses in their home countries. Their responses were strongly in favour of all the aspects outlined in the UICEE questionnaire. In addition, the participants also made comments on UNESCO’s form Evaluation of UNESCO’s Training Activities in the Basic and Engineering Sciences (comments by Trainees).
According to the comprehensive course evaluations, the courses were extremely beneficial for the trainees. The responses were so positive that the Centre intends to repeat this course, subject to availability of funds. It is anticipated that the course will be offered to young academic teachers in Australia and abroad on a commercial basis.
The duration of the second course was eight working days, which allowed for a slight expansion of the course as well as an increase of time for hands-on activities in the computer laboratory. The methodological units of the second course, based on the contents of the teaching manual, covered the following broad topics:
The UICEE has encouraged the trainees to organise and run similar courses in their home countries with assistance from the UICEE. Financial assistance from UNESCO also will be sought for this activity.
Research and development projects mentioned in this paper demonstrate a number of successful activities in the area of computer-based education carried out by members of the EEERG. The transfer of the EEERG to Monash’s UNESCO International Centre for Engineering Education has given a new impetus to the work in this important research area.
Research into educational processes in general, and computer-assisted instruction and the application of computers in teaching practice in particular, is essential for the further advancement of engineering education and industrial training. Much can be achieved if a special scheme is established to facilitate this area of academic endeavour.
This paper presents the comprehensive approach undertaken by the EEERG and UICEE in research and development activities in the application of computers in electrical and electronic engineering education. Computers have now become indispensable in the teaching/learning process carried out in engineering. This relatively new medium has already had an enormous impact on the status and quality of engineering instruction, but it still requires more and extensive studies to develop a suitable methodology to help make educational and training programmes more effective and reliable. More effort and resources must be made available to further advance this area of academic endeavour to this end.
1. Pudlowski, Z.J., Research projects on computer-based education in electrical engineering. Proc. of the 4th Symposium on Microcomputers in Education - CE-4, Zakopane, Poland, 49-64 (1993).
2. Pudlowski, Z.J. and Darvall, P.LeP., The UNESCO International Centre for Engineering Education. Inter. J. of Engng. Educ., 10, 2, 157-163 (1994).
3. Pudlowski, Z.J. and Kerr, I.R., Report on the Application of Computer-Aided Instruction for Engineering Students in the Faculty of Engineering, Monash University. UICEE, Faculty of Engineering, Monash University (1994).
4. Tao, S., The design of a hypermedia knowledge base for promoting the transfer of knowledge and skills. Proc. of the 1st Asia-Pacific Forum on Engineering and Technology Education, Monash Engineering Education Series, UICEE, Monash University, Melbourne, Australia, 291-295 (1997).
5. Mendrela, E., Pudlowski, Z.J. and Choi, H.Y., A new experimental procedure in electrical power engineering training. Proc. of the 2nd AAEE Annual Conference. Melbourne, Australia, 483-488 (1990).
6. Shuwayhat, K. and Pudlowski, Z.J., Computer simulation in the teaching of digital gates and systems. Proc. of the 6th AAEE Annual Conference. Sydney, Australia, 740-745 (1994).
7. Turowski, M., Lisik, Z. and Pudlowski, Z.J., SEMDEM — Educational software for bipolar power devices. Proc. of the 2nd International Seminar on Power Semiconductors (ISPS’94), Prague, Czech Republic, 179-186 (1994).
8. Pudlowski, Z.J. et al, Computers in Electrical Engineering Education - Research, Development and Application. Monash Engineering Education Series, UICEE, Monash University, Melbourne, Australia (1995).
9. Pudlowski, Z.J. and Hadgraft, R.G., The application of computer-assisted traning programmes in engineering education - A course overview. In: The Application of Computer-Assisted Training Programmes in Engineering Education, Monash Engineering Education Series, UICEE, Monash University, Melbourne, Australia (1996).
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