Extended Summary pp.570-576 Design and Implementation of Study Support System for Electric Circuit Using Virtual Oscilloscope Masashi Ohchi Member (Saga University, masashi@ace.ec.saga-u.ac.jp) Noriyuki Aoki Student Member (Saga University, aoki@ace.ec.saga-u.ac.jp) Tatsuya Furukawa Member (Saga University, tach@ace.ec.saga-u.ac.jp) Kenji Furukawa Non-member (Fujitsu Ten Co. Ltd) Keywords: virtual laboratory, Java, electric circuit, transient phenomena, virtual oscilloscope The authors have designed and implemented Virtual Laboratory on the computer systems. Some of the systems are implemented under Web based learning environments where server/client model andjavetechnologies are adopted. In the conventional system, students study the basic alternating circuit theory and they can only observe the steady state behaviors of waveforms on the electric circuits using the Virtual Oscilloscope. In this paper, we will describe the study support system for electric circuits including transient phenomena using Java. Fig. 1 shows the system configuration of the present study support system. When a student opens the implemented Web page, a Java Applet is downloaded and executed on the client (user side) computer. The system has some functions for studying electric circuits. For examples, explanation of a basic electric circuit theory, observing voltage waveforms using the Virtual Oscilloscope, problems in electric circuits. The scores that students get will be saved on the WWW server by using Java Servlet container. Since they are saved in HTML files, any students can easily see the own scores using Web browser. Fig. 2 shows the snapshot of the explanation window of the electric circuit. If a student clicks the right button of the mouse on the window, the contents change the next page. Moreover, if the left button of the mouse is clicked, the page goes back to the previous page. The menu window has ten buttons, explanations, hints, problems, the Oscilloscope and so on. When a student clicks the question button in the menu window, the question window will be displayed. Fig. 3 shows the snapshot of Virtual Oscilloscope for observing the voltage waveform. It is implemented by Java Applet. There are some control knobs with the Virtual Oscilloscope. For example, Voltage range, GND position, Focus control, Intensity control, Scale controls, Trigger controls, Fig. 2. Explanation of electric circuit Fig. 3. Virtual Oscilloscope Fig. 1. System configuration Time scales and Horizontal position. It is able to observe the transient voltage waveform of the RL, LC, RC, RLC circuits. The voltage and the values of LCR(inductance, capacitance, resistance) are available to change using slider in the system. The implemented system is very significant for studying the basic electric circuit including transient phenomena as aphysicalphenomena. It is considered that students can study electric circuits including transient phenomena easily using the present system. 5
Design and Implementation of Study Support System for Electric Circuit Using Virtual Oscilloscope Masashi Ohchi,Member,Noriyuki Aoki,Student Member, Tatsuya Furukawa,Member, Kenji Furukawa,Non-member We have designed and implemented the Virtual Laboratory on the computer systems. Some of the systems are implemented Web based learning environments where server/client model and Java technologies are adopted. In our conventional systems, students study the basic alternating circuit theory and they can only observe the steady state behaviors of waveforms on electric circuits using Virtual Oscilloscope. In this paper, we will discribe the study support system for the electric circuits including transient phenomena using Java. Java Keywords: virtual laboratory, Java, electric circuit, transient phenomena, virtual oscilloscope 1. Web PC (1) (2) PC Java 840-8502 1 Department of Electrical and Electronic Faculty of Science and Engineering, Saga University 1, Honjo-machi, Saga 840-8502 652-8510 1 2-28 Fujitsu Ten Co. Ltd 1-2-28, Gosyotori, Hyogoku, Kobe 652-8510 (3) (6) Java (7) Web (8) Web Java PC( ) (3) (4) 570 IEEJ Trans. FM, Vol.126, No.7, 2006
GND 2. 2 1 HTML Web 1 Java ( )PC 2 WWW (World Wide Web) Java (10) WWW CGI CGI Java CGI Java OS 2 2 2 2 1 1 Fig. 1. Fig. 2. 2 Whole flowchart. System configuration. Java 3 2 2 2 1 2 3 4 A 126 7 2006 571
3 Fig. 3. Class Configuration of Learning Applet 5 6 7 8 9 4 HTML Web Web WWW Graphics 4 RL (t=0 ) 2 2 3 5 5 6 1 6 Web Web 4 Fig. 4. Instruction window 5 Fig. 5. Problem window. Web 6 CGI Web HTML Web 2 2 4 6 7 ID 572 IEEJ Trans. FM, Vol.126, No.7, 2006
8 Fig. 8. Class Configuration of Applet Oscilloscope 6 Fig. 6. Check of answer. 7 ID 9 Fig. 7. ID and password. Fig. 9. Virtual Oscilloscope. open_ssl mod_ssl (11) HTML 3. 8 3 1 9 Oscilloscope Web RC V 1 V 2 10 GND (9) RL LC 3 2 11 12 11 RLC R L C A 126 7 2006 573
12 ( ) Fig. 12. Virtual Oscilloscope(transient phenomena). 10 Fig. 10. Adjustment parameters using dial 11 Fig. 11. Transient of circuit. 13 RC RL LC RLC 13 Fig. 13. Displayed wave using Virtual Oscilloscope. 3 3 GND 14 574 IEEJ Trans. FM, Vol.126, No.7, 2006
14 Fig. 14. Help Window. 2005 3 17 8 19 18 1 24 4. Web 5. Java () PC Web 1 T. Furukawa, M. Matsuo, S. Miyazaki, H. Dozono, and M. Ohchi: Development of Distributed Educational Support System for Learning Image Processing, IPSJ, Vol.41, No.12, pp.3208 3113 (2000 12) (in Japanese) 42, 12, pp.3208 3113 (2000 12) 2 T. Furukawa, M. Ohchi, and K. Kurakaki: Design and Implementation of Streaming VideoandMeasurement Data Distribution System over the Internet, IEEJ Trans. EIS, Vol.125, No.7, pp.1077 1083 (2005 7) (in Japanese) C 125, 7, pp.1077 1083 (2005 7) 3 S. Doi, T. Furukawa, and M. Ohchi: Construction of Support System for experiment using Java Development of Virtual Oscilloscope Applet for Studying, SICE Kyushu branch, Vol.18, No.403, pp.315 318 (1999 10) (in Japanese) Java 18 Vol.18, No.403, pp.315 318 (1999 11) 4 T. Furukawa, M. Ohchi, and S. Doi: Development of study Support System for Fundamental Electric Circuit, The Papers of Joint Technical Meeting on Frontier in Education, IEE Japan, FIE 02 7, pp.35 38 (2002 9) (in Japanese) FIE 02 7, pp35 38 (2002 9) 5 M. Ohchi, T. Furukawa, and K. Furukawa: Development of Self Study Support System for Transient Phenomena in Electric Circuits Using Java, The Papers of Joint Technical Meeting on Frontier in Education, IEE Japan, FIE 03 31, pp.51 53 (2003 9) (in Japanese) Java FIE 03 31, pp.51 54 (2003 9) 6 K. Furukawa, T. Furukawa, and M. Ohchi: Development of Self Study Support System for Transient Phenomena A 126 7 2006 575
in Electric Circuits using Laplace Transformation, SICE Kyushu branch, Vol.22, No.203A4, pp.253 254 (2003 11) (in Japanese) 22 Vol.22, No.203A4, pp.253 254 (2003 11) 7 http://java.sun.com/applets 8 E Learning 15 4 No.304 (2003) 9 http://java.sun.com 10 http://java.sun.com/j2ee/ja/servlet/index.html 11 http://www.apache.org 1956 6 21 1984 3 4 1986 1987 1993 4 2001 4 AEM 1964 12 8 1989 3 4 NTT 1991 4 1993 4 2000 4 2002 1 ( ) AEM 1980 6 23 2003 3 4 2005 3 4 1981 5 20 2004 3 2006 3 4 576 IEEJ Trans. FM, Vol.126, No.7, 2006