Sunheum Lee

Development of Home Network Gateway Supporting both Wire and Wireless Communication

A home network gateway has been developed, which supports both wire and wireless communication functions. ZigBee and PLC modules are taken as communication hardware and a conversion protocol is implemented to be able to smoothly exchange the information between the two hardware modules. The developed gateway shows good performance and can supports various home network service configurations.

Implementation of a web-based hybrid educational system for enhancing learning efficiency of engineering experiments

To enhance the excellence, effectiveness, and economical efficiency in the learning process, we implement a creative hybrid educational system for engineering experiments where web-based virtual laboratory systems and distance education systems are properly integrated. In the first stage, we designed client/server distributed environment and developed web-based virtual laboratory system for electrical/electronic circuit experiments. The proposed virtual laboratory system is composed of three important sessions and their management system: concept-learning session, virtual experiment session, assessment session. With the aid of the management system every session is organically tied up together to achieve maximum learning efficiency. In addition, every activity done during the virtual laboratory session are recorded on database and will be provided to the learners as the printout report included their own experimental information and results. With this new system structure, the learners can compare theoretical and experimental data; develop their capability in designing and analyzing the circuits; and make use of auxiliary educational tools for understanding complicated concepts. In the second stage, we have implemented efficient and cost-effective distance laboratory systems for practicing electrical/ electronic circuits, which can be used to eliminate the lack of reality occurred during virtual laboratory session. The use of simple and user-friendly design allows a large number of people to access our distance laboratory systems easily. Thus, self-guided advanced training is available even if many expensive types of equipment will not be provided in the on-campus laboratories. During distance laboratory session, the learners change the settings of the input signal and the values of circuit elements, observe the output waveform from the web camera, and obtain image information regarding their experimental results. The proposed virtual/distance laboratory systems can be used in stand-alone fashion, but to enhance learning efficiency we integrated them and developed a creative hybrid education system for engineering experiments. Our hybrid education system provides interactive learning environment and a new approach for the delivery of engineering experiments.

The Mobile Quiz System Using SMS

In this paper, a mobile quiz system using SMS has been developed, which can be conveniently used on the spot of education. The system immediately not only provides each individual student with the results of his/her quizzes but also a instructor with the statistics of the results by SMS. Field tests of the quiz system have shown that it can be effectively used as a good teaching tool for teachers getting immediate feedback from participants in the lecture and adjusting teaching level as well as for inducing more interest in learning from participants and raising their concentration on the class.

New Performance Evaluation Method of Focused Ultrasonic Transducers By Using Virtual 3D Graphic

The performance of ultrasonic testing systems for industrial or medical purpose largely depends on the performance of ultrasonic transducers. Generally, the information about an ultrasonic transducer performance characteristics are expressed by the ultrasonic R/F signal back from a reflector and its frequency characteristics in the data sheet provided by manufacturers. In case of focused ultrasonic transducers, the two pieces of information can, however, hardly assure that the focused ultrasonic transducer would produce well-focused C-scan images. Therefore, we propose the measured size of focal spot and the reconstructed shape of effective focal zone in the focused sound field as novel measures for the performance evaluation of the focused ultrasonic transducers. The process of getting the both measures of the transducers is conducted by the implemented software including sound field scanning and virtual 3D reconstruction functions which requires the echo of a point reflector. The proposed method could, otherwise impossible in the existing method, effectively and simply distinguish superior ones among many transducers made in the same specification and be also used to detect the performance degradation due to the aging of the transducers. Eventually, the quality of performance of the ultrasonic testing systems for industrial or medical purpose is secured.

The Construction of Remote Microcontroller Laboratory Using Open Software

A microcontroller can be considered a self-contained system with a processor, memory and peripherals. It is used in automatically controlled products and devices by programming. Therefore it is adopting with the essential subject in our department. We implemented a remote laboratory for 80196KC microcontroller. The remote laboratory provides functions with which learners can perform experiments by remote-controlling circuits and equipment related to experiments and practices on the Web and gets data and image information, so through it learners can make realistic experiments at any time and in any place. Although student can not physically touch any equipment, they can confirm the operation process of the 80196KC microcontroller by observing the result of experiment transferred through the web camera. The remote laboratory module based on Internet open sources such as JAVA Web start technology, FTP technology and Telnet technology in server-client environment can be implemented at low cost. It has the object of introducing remote experimentation, offering to students the opportunity to run a C code for 80196 KC microcontroller. Our remote Lab, therefore, is a useful tool that allows students to make real experiments with 80196 KC microcontroller. It will be used an auxiliary lab for teaching and learning microcontroller.

Education Embedded System for Remote Control

This study implemented a remote control system using PDA based on WINDOWS CE.NET. In existing remote control systems, the user generally controls remote objects and obtain data using a computer, which is a local system connected to the Internet, and the remote objects are connected to server computers. In order to control remote objects, the user has to have a computer, a space to use the Internet, and wired Internet. The system proposed in this study uses an embedded board as a server and PDA as a client. Thus, the user can control remote objects at any place as long as wireless Internet is available. In addition, because an embedded board is used as a server, the system has the characteristics of high performance and low power consumption. The proposed system provides not only remote control environment using PDA but also conventional control environment using a computer as a client. In case PDA is not available, remote objects still can be controlled from any place as long as there are wired Internet and a computer.

Graduation Project: Development of an Automation System for Filter Quality Test Using LabVIEW

This paper presents a system of automatic filter quality test for the filter activeness during the process of the filter production was embodied with LabVIEW server and conveyer system. The LabVIEW server is LabVIEWs function as web server which can be remote controlled during filter quality test through on web. The conveyer system is constructed with Conveyer, Network Analyzer and PC Camera. The LabVIEW server controls conveyer motor and sensor using DAQ card and controls Network Analyzer using GPIB card for measuring S parameter of filters. Moreover, PC camera is for monitoring the process of remote controlling during the filter test. And the data base construction from results of Network Analyzers measurement made possible to manage special information of filters.

Moodle`s Cloze type quiz editor development by using Javascript

Moodle is a web-based open-source LMS. This system provides the effective functions for making a various types of quizzes easily. Any interface for making a Cloze-type quiz conveniently, however, are not provided in the Moodle. In this paper, a web-based program has been developed which helps users make the Cloze-type quizzes easily. The program provides a convenient interface and achieved the considerable reduction in time-cost of making the Cloze-type quiz. The program is very helpful for users to try to make a variety of quizzes by using the Cloze-type.

A Design and Implementation of Embedded RFID Middleware System based SOA Environment Using .Net Compact Framework

This study designed and realized a new type of RFID middle-ware based on .NET Compact Framework platform using PXA255 embedded board and Windows CE as operating system. The proposed embedded RFID middle-ware system controls via LAN a number of RFID sensors using RS-232 as interface and was designed on the basis of components of each function necessary RFID middle-ware. Application module operating in the SOA environment analyzes the data received from the RFID sensors with the embedded RFID middle-ware and in turn performs appropriate business logic. Client module to be used by end users can use RFID information in database, by web method call of application.

A Novel Method for Performance Evaluation of Focused Ultrasonic Transducers

The characteristic information about an ultrasonic transducer is generally described by the ultrasonic R/F signal back from a reflector and its frequency characteristics in the data sheet. The information can, however, hardly assure that the focused ultrasonic transducer would produce well-focused sound fields which the performance of the transducer absolutely depend on. Therefore, we propose the measured size of focal spot and the reconstructed shape of effective focal zone in the focused sound field as novel measures for the performance evaluation of the focused ultrasonic transducers. The process of getting the both of the transducers is conducted by the implemented software including sound field scanning and virtual 3D reconstruction functions which requires the echo of a point reflector. The proposed method could effectively distinguish superior ones among many transducers made in the same specification and be also used to detect the performance degradation due to the aging of the transducers.