• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.3
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• pp.65-71
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• 2002

Friction welding has may merits such as energy efficiency, simple processing, etc. but it is difficult to obtain good welding at the welded interfaces and heat affected zone. It is discovered that stress singularity exists at the interferes and heat affected zone. The computer program based on boundary element method is utilized in this study. A mathematical model is implemented based on results from several experiments performed at and around the welded interfaces and heat affected zone of disimilar metals under static and dynamic loadings. This stay is to investigate the characteristics of the deformation and fracture behavior around interfaces for friction welded materials under static tensile load. Also, the stress distribution at the tip of crack is analyzed by using BU based on Kelvin's solution of 2-dimensional binding zone. The results of BEM are identical with those in case of considering interfaces of both heat affected zone. Also, stress singularity at the tip of interfaces appears when the elastic modulus ratio is 1.07.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.391-396
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• 2000

Today most companies are designing their automobile shapes by using 3 dimensional CAD software, CATIA. And they used to design 2 dimensional press dies to do some elastic work on their products, but they are currently trying to make use of dimensional software, Pro-Engineer. In this case, they have to change the 3 dimensional product design data to the proper format data for the following process. This paper will show the data loss and the deformation during data transfer between CATIA and Pro-Engineer, and then suggest a solution for these problems. Product's surface will be automatically placed by automatic press tipping angle setting in CATIA to prevent the product from being stuck in the press die. The 2 dimensional section view which is based on the tipping angle setting is created by Z-map. And, to remove the data loss and the data deformation in pro-Engineer, the product surface are delivered to the next process after it is changed to the 2 dimensional Z-map curves in CATIA. finally, this paper suggests an algorithm to develop the automatic design program for the press layout which regenerates product shape surface from the previous process.

• The Journal of the Korea Contents Association
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• v.12 no.1
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• pp.38-47
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• 2012

In order to extend the activity range of visually impaired persons, we design and implement a navigation system that supports road information services and points of interest. The proposed navigation system consists of route creation modules and storage modules for visually impaired persons. In particular, the main interface of the navigation system are implemented using TTS(Text-to-Speech) program for sound and braille module that outputs braille with sense of touch. We also use google map APIs that can provide latest map information for the navigation system.

• Proceedings of the Korea Contents Association Conference
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• 2005.11a
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• pp.43-47
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• 2005

With the high interest and the results of active research in life science and Bioinformatics recent years, various information and resources have been produced and new algorithms have been developed to analyze those. Web Services is a computer technology using XML, SOAP, WSDL and UDDI. This paper introduces the One Stop Web Services program developed in CCBB which has a graphic user interface for users.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.343-347
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• 2003

Recently, the ratio of marine casualty has been marked about 72% in fishing boat and small ships which not less than 100 tons in Korea. It is mainly against navigation regulations such as look-out, selecting the ship's course and checking the ship's position according to the analysis of marine accident. In this paper, we proposes the Intelligent Navigation Guiding System(INGS) that provides an optimum route for an operator of small ships. INGS consists of program for route planning, interface module and GPS Plotter. we obtained optimum route from specific position to established route by INGS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.414-417
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• 2001

In this paper the fuel filling system for a city bus was investigated in order to improve the system. The suggested fuel filling system was designed to have functions of identifying a bus arrival tine, and measuring volume of fuel filled. The system consisted of four parts of bus identification, IBM PC, interface card, fuel filling control system and program for integrating all parts. It is believed that the information obtained by this system can be used for analysing driver's driving habits and performance of engine of a bus, and accordingly the prime cost can be reduced.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.216-221
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• 2003

A thermal vacuum chamber is mainly used to simulate thermal environments of a test satellite in satellite orbits in which daily temperature variations range from 80K to above 400K depending on solar radiation under the vacuum below $10^{-4}$ torr. The test facility is quite complex and consists of expensive parts. So any modification of control software is discouraged in fear of unexpected system failure. The purpose of this study is to develop a realtime dynamics model of the thermal vacuum chamber in view of controller design and simulate its electrical inputs and outputs for interface with a PLC (programmable logic controller). A PLC program that was used in the thermal vacuum chamber is applied to the realtime simulator. The realized simulator dynamics is found to be quite similar to that of the thermal vacuum chamber and serve to an appropriate plant to verify the control performance of a programmed PLC.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4569-4573
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• 2011

Resolver doesn't have a advantage to price in comparision with encorder. However, resolver is used to the case of detecting a absoluteness position and is used to a fine control in the place of having a stability by mechanic. The position by resolver and the method by speed detecting is applied by observer and have a part of processing analog signal. In this paper, we used the method which output signal of resolver is demodulated by cos and sin waveform and the demodulated analog signal is transmitted to controller. We designed the estimated on the program of a controller and observed the movement on the low speed.

• The Transactions of the Korea Information Processing Society
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• v.7 no.5
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• pp.1330-1340
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• 2000

Multimedia isn ow applied to various real world areas. In particular, the focus on multimedia system and CSCW(Computer Supported Cooperative Work) has increased. In spite of this current trend, however, the study of fault tolerance for CSCW has not yet fully progressed. We propose EDR_MSCW. It is a system that is suitable for detecting ad recovering software error based on multimedia computer supported cooperative work as DOORAE by using software techniques. DOORAE is a framwork for supporting development on multimedia applications for computer-based collaborative works. When an error occurs, EDR_MCSCW detects an error by using hooking methods in MS-Windows API(Application Program Interface) function. If an error is found, we present a checkpointing and recovery algorithm which has the removal function of the domino-effect for recovering multimedia and CSCW by using stack.

• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.201-203
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• 2002

In recent years there has been a growing interest in renewable energy systems due to the environmental problem and the economic benefits of fuel savings. Such systems are usually connected to the existing power grid for "fuel displacement" purpose as well as of earning some "capacity credit". Wind power generation system(WPGS) is one of the most useful energy resource using natural environment. So far, it was very difficult to simulate the dispersed generation system including WPGS using EMTP or EMTDC because the source of the dispersed generation system has a particular wind power characteristic equation. In this paper, a novel simulation method of WPGS has proposed and a new wind turbine component for EMTDC is also developed. The wind power characteristic equation of wind turbine is used in order to realize the WPGS in EMTDC simulation. And the real field data of weather conditions is interfaced to EMTDC using Fortran program interface method. Consequently the simulation of WPGS using field data is realized in this paper and shows acceptable results.