Interactive www Course „Electronic Devices and Circuits”

Stuchlíková Ľubica, Gron Michal, Csabay Otto, Helbich Marek, Radobický Jozef, Beňo Ján, Mondočko Peter, Vacek František, Hulényi Ladislav, Kinder Rudolf, Rovanová Ľubica,

Redhammer Róbert, Nemčok Peter, Bednár Martin, Števove Milan, Lazišťan Filip, Benkovič Michal, Švrček Peter, Benko Martin, Nagy Arnold

Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkovičova 3, 812 19 Bratislava, Slovakia

E-mail: lubica.stuchlikova@stuba.sk

Abstract

This article shows the authors' motivation, experience in design and realization in design and realization of interactive www course “Electronic devices and circuits”. This eLearning project is free accessible on the self-educational portal „eLearn central“ for the students. This portal uses learning environment Moodle, which supports international standard SCORM.

1. Introduction

Nowadays students get more information in a single year than their grandparents did in all their lives. The amount of knowledge in most scientific disciplines doubles every seven to 10 years. In the past 25 years, whole new fields of science - such as biotechnology and computer science - have emerged from obscure specialties to essential fields of study that can be, and should be, found at most institutions [1]. Universities are the repository and the transmitters of the nation’s scientific knowledge, so they must keep pace with the rapid expansion of knowledge. Otherwise, their students would receive an outdated education. This trend of course concerns to Faculty of Electrical Engineering and Information Technology students, as well.

2. Motivation

Our students engage in Electronic devices and circuits subject in their second year of a bachelor study at the Faculty of Electrical Engineering and Information Technology, Slovak University of Technology in Bratislava [2]. The subject Electronic devices and circuits deals with basic knowledge of physical principles, electrical properties, technology and constructional principles of passive and active electronic devices, the basic knowledge about electronic systems, circuit properties of passive and active devices, application of diodes, transistors,

operational amplifiers, digital circuits and another semiconductor devices in different applications. It is well known that it is very difficult to understand basic principles of electronic devices and systems without understanding inner processes in semiconductors. In the case of technical education a student must have traditional laboratory lessons to obtain practical knowledge on the subject. Practical experimental work in laboratory is an important component of education process in general. Practical laboratory exercises of this subject enable verification of knowledge received from lectures by measuring of physical dependences and properties of individual semiconductor devices and systems. Students come from secondary schools to the university with different levels of knowledge. These differences are mostly evident in technical subjects. All students meet with physics of semiconductors for the first time, additionally, students coming from secondary grammar schools have usually no experiences with practical electronic measurements and with electronic devices. In this case we have not very pleasant situation for teachers: there are three different main groups of students • part of students in general with very good study

results have no experiences, no skills with practical measurements, and this subject is for them the source of frustration (about 25 %)

• part of students who without problems make practical experimental work in laboratory (about 50% )

• part of student who have skills and own practical experiences – mostly they were students from High school with technology education – electronics technology or radio amateurs. Practical laboratories are very easy for these students and they usually undervalue the careful preparation on exam (about 25 %).

One of way how we can help student to reduce knowledge differences, to motivate students and to raise education efficiency of subject Electronic devices and circuits was to create an eLearning source of information - interactive

www course “Electronic devices and circuits” to enhance the quality of traditional teaching methods.

2. “Electronic devices and circuits”

The course “Electronic devices and circuits” is accessible on the self-educational portal „eLearn central“ for students.

Fig. 1. Visitor´s view of the Student menu “Electronic devices and circuits”

2.1. A Learning Environment

The „eLearn central“ portal is located on the server of the Department of Microelectronics FEI STU on the following link http://ec.elf.stuba.sk. The current version of this portal uses a course management system Moodle 1.7 (Fig. 1). Moodle (Modular Object-Oriented Dynamic Learning Environment) is an open source software package designed using sound pedagogical principles, to help

educators create effective internet-based courses and web learning sites [3].

2.2. The course Content

The course “Electronic devices and circuits” (Fig. 1) includes 10 lessons, 30 interactive animations, glossary with more than 300 terms and number of hypertext references. A single lesson gives the basic principle definitions and terms connected with electronic devices and circuits to FEI students in the second year of their Bachelor study. Lesson titles are following: • Electronic systems, devices and passive circuits • Semiconductors and pn junction of semiconductors • Semiconductor diodes and diode circuits • Bipolar junction transistor • Bipolar junction transistor dynamical parameters • Unipolar transistor • The bipolar junction transistor as an amplifier - the

common-emitter • Further basic scheme with bipolar junction transistors • Operational amplifier • Digital circuits and systems

2.3. Lessons - SCORM package

The lessons were converted into a SCORM 1.2 package (Fig. 2). SCORM is a widely approved eLearning standard (Shareable Content Object Reference Model).

Fig. 2 SCORM package in Moodle

SCORM describes a specific way to deliver some eLearning contents. SCORM is a part of a strategy called the Advanced Distributed Learning (ADL) initiative [4]. SCORM is a collection of standards and specifications adapted from multiple sources to provide a comprehensive suite of eLearning capabilities that enable interoperability, accessibility and reusability of web-based learning content. SCORM defines a reference model for sharable learning content objects that meet these high-level requirements. SCORM 1.2 packages were created by software THESIS Professional [5]. The THESIS product family comprises a set of SCORM compliant eLearning tools that make it possible for educators to use popular Microsoft Office programs, such as Word, PowerPoint, Excel, Visio, and MSProducer to create learning objects for e-learning.

2.4. Course - Interactive animations

Our ambition was to assist the students in understanding of inner processes in semiconductors and electronics circuits through interactive animations. Static pictures and characteristics do not much support students’ imagination of such inner processes. More than 30 interactive animations have been developed in Adobe Flash [6] for this course. There are interactive animations of passive devices, passive filters, diodes and their usage in electronic circuits, as well as BT, HBT, JFET and IGBT transistors, real and ideal MOS structures, examples of planar technology produced diodes and bipolar junction transistor, digital circuits and gates are included.

Fig. 3. Logic TTL NAND gate 7400

Fig. 4. A bipolar junction transistor making by planar epitaxy technology Adobe Flash enables to create everything from a simple animation to a complex interactive web application as online market is. It is possible to enrich Flash applications by addition of pictures, sounds and a video.

Fig. 5. Silicon crystal (i, n, p type) We decided to use this authors´ tools for interactive animation creation because it is able to program this important interaction and it works with scaleable vector graphics. It fulfilled the requirement for the smallest size of animations, vector graphic with the view of non-decreasing quality at higher resolution. An output format of animations can be added to web pages. These

programme packets were purchased by the Department of Microelectronics FEI STU for non commercial purposes. Design of interactive animations can be divided into two groups. The animations created solely by using Adobe flash tool are in the first group (24 animations) (for example Fig. 3 - Fig. 5). The second type of interactive animations (6 animations) was created by using software Adobe Flash and SPICE. Complicated physical problems were solved by involving other teachers of our Department of microelectronic who specialise in a given problem [7 - 10]. Feedback questions for users were put below each animation as a link: “Please answer these questions if you want to support our work. Thank you.” Students/users were to answer the following questions: • Do you have any experience with eLearning? • Does this method of study suit you? • Is this method of study technically accessible for

you? • Can you understand the animation shown above? • Is the shown animation interactive enough? • Has this animation helped you to understand the

substance of the described phenomenon?

2.5. Lesson Quizzes

The lessons have been supplemented by two types of interactive self testing modules. Quizzes were created in Moodle XML format with our "questions and answers editor" (Fig. 6).

Fig. 6 Our Moodle Question and Answer Editor

Fig. 7 Quizzes for Fast revision of knowledge

Fig. 8 Quizzes quiz with a feedback possibility This editor allows that various question types can be mixed in a single text file and the format also supports Multiple-Choice, line comments, question names,

Question Incorrect answer

Feedback

feedback and percentage-weighted grades etc. There are available at least 5 various quizzes with 10 multiple-choice questions supporting single or multiple answers in both types of quizzes. Results are listed in %. The best results are stored in users’ accounts. The user is informed about these results in the case he repeats the test. The first type of quiz is assigned for fast revision of knowledge (Fig. 7). Students can see not only their results in %, but they can see expected correct results after finished of test. The second type of quiz is a learning quiz with a feedback possibility (Fig. 8). When a student does not answer correctly, the quiz automatically returns him back to the text related to the question. The student has an opportunity to repeat the answer after that. He/she may proceed in carrying out the quiz only if his/her answer is correct. This is a very simple way to learn this topic.

2.6. Course Glossary

Moodle has a possibility to create a glossary which can be maintained by the instructor or collaboratively by the students.

Fig. 9 Visitor´s view of the „eLearn Central“ Glossary Terms in the glossary that appear in the course can be auto-linked back to the glossary. We decided to use this ability of Moodle – modul Glossary. We are creating our own glossary. Now the glossary has more than 300 explanations. Our goal is to prepare glossary with all terms used in our education text. This glossary is

accessible not only for this course but for the the whole portal „eLearn Central” (Fig. 9).

3. Courses creators

The course “Electronic devices and circuits” is a result of collaboration of teachers and students from „eLearn central team”. We have been communicating together on regular basis, either in face-to-face meeting, or by e-mail. Each consultation has been based on teacher-student interaction with equal rights. The teacher-student cooperation has following reasons. Teachers are experienced in teaching, they have expert skills, they can find the most appropriate ways how to obtain new knowledge and they have enthusiasm. Students have the necessary software practical dexterity, they are able to learn quickly how to work with a new programme tools, such as Adobe Flash, they have creativity, new views on a topic, and enthusiasm, as well.

4. Summary

We created an eLearning source of information - interactive www course “Electronic devices and circuits” to enhance the quality of traditional teaching methods – we created conditions for blended form of study. This course mainly serves for FEI students in the second year of their Bachelor study as an alternate source of information. Everyone who is interested in this topic can access this course, because the access to this course is free. We gained a lot of experience in support eLearning materials design. All our outcomes are the result of reciprocal interactions between teachers and students in „eLearn central team”. Operation of portal “eLearn central” started on December 16, 2004. Here we can analyze our users` response. Between December 16, 2004 and October 28, 2006, the development version of course “Electronic devices and circuits” was visited more than 40 000 times by 540 users. The profile of our web page visitors corresponds mostly to the second year FEI STU students, who have no problems in access to Internet and have some experience with web learning and this kind of education suits them. The number of our site visitors dramatically raised before an Electronic devices and circuits tests. The users have also the right to give an anonymous feedback to an individual interactive animations and courses. The feedback was very positive and it helped us to improve our work. Our experience in using of our self-educational portal for students „eLearn central” in a standard and a blended

form of education we enriched in a distance study last year. Distance students feedback was unambiguous and positive. The students used all accessible eLearning materials, and there was only one remark – to complete the course as soon as possible, which is now being developed.

Fig. 8 Flash memory Cell Structure in English

Fig. 9 A SiGe heterobipolar transistor (a common-emitter circuit) in English

And future? At present, we are working on the English version of the coarse and animations (Fig. 8 and Fig. 9), so that we can extend our cooperation with other teams working on similar problems. In future, we would like to add sounds to the interactive animations to make them more attractive and easier to use. According to our experience, we think that cooperation with students is one of the most prospective ways in support of eLearning materials design. Essential conditions for support eLearning materials design by teachers and students are: • Enthusiasm • Constructivism • Innovation • Coequal Collaboration.

5. Acknowledgment

This work was partially supported by project KEGA 3/4009/06.

6. References

[1] College Costs Putting into Context, American Council on Education, http://www.ofr.harvard.edu/college_costs.pdf, 2006 [2] Elektronické prvky a obvody (2314), http://www.kme.elf.stuba.sk/kme/predmet.php?prd_id=4, 2006 [3] Moodle, http://moodle.org/, 2006 [4] SCORM 2004. Advanced distributed learning http://www.adlnet.gov/index.cfm, 2006 [5] THESIS Professional: E-learning Tools, http://www.hunterstone.com/thesis.asp, 2005 [6] Flash Professional 8, http://www.adobe.com/products/flash/flashpro/, 2006 [7] M. Ťapajna, L.Harmatha: Determining the Generation Lifetime in a MOS Capacitor Using Linear Sweep Techniques. In: Solid-State Electronics, 48, 2004, pp.. 2339-2442. [8] J. Racko, A. Grmanova, J. Breza: Extended Thermionic Emission-Diffusion Theory of Charge Transport Through a Schottky Diode. In: Solid State Electronics, 39, 1996, pp. 391-397. [9] M. Kadlečíková, J. Breza, M. Veselý, I. Červeň: A study of synthetic sapphire by photoluminescence and X-ray diffraction, Microelectronics Journal 34 (2003) 95-97 [10] M. Huba, K. Žáková, P. Bistak:: WWW a vzdelavanie, Bratislava : FEI STU, 2003. 137 s. ISBN 80-227-1999-4