• KIEE International Transactions on Power Engineering
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• 제5A권4호
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• pp.366-370
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• 2005

To meet increasing power demand, 500 kV power systems are under consideration in the regions of some Middle Asian countries. As the power system voltage becomes higher, the cost for the power system insulation increases significantly. 500 kV transmission systems will become the basis of a region's power system and they require much higher system reliability. Consequently, by the methods of limiting overvoltages effectively, a reasonable insulation design and coordination must be accomplished. In particular, the Substations must be constructed to be of outdoor type. In order to determine the various factors for the insulation design, the EMTP (Electro-magnetic transient program) is used for the magnification of transient phenomena of the 500 kV systems in the planned network. In this paper, we will explain the calculation results of lightning overvoltages by the EMTP for lightning protection design for the 500 kV substations. To obtain reliable results, the multi-story tower model and EMTP/TACS model are introduced for the simulation of dynamic arc characteristics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.38-39
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• 2008

KEPCO conducted the project called the "Feasibility Study for the Han (Ghana) - Bobo Dioulasso (Burkina Faso) - Bamako (Mali) Interconnection Project" as its first African project. This paper deals with power system analysis and Transmission line and substation design of approximately 750 kilometers of the 225 kV single circuit transmission lines and six substations. The main contents of the power system analysis results and preliminary engineering design include power flow, transient stability, eigenvalue analysis, transmission line design, substation design and economic analysis.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.872-876
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• 1996

Most studies of rotary machinery design have been performed to establsih a new mechanism or a dramatic combination of machine elements for the power transmission. Although the rotary machine is worked very efficiently, that still has a major work to better performance which is the optimization of the selected mechanism for the mechanical efficiency, low vibration and noise, or customer interest. This work presents a practical approach used for washer's efficiency and machinery vibration and noise reduction along with a systematic procedure. Also for the confirming the study, a computer simulation program and a real working mock-up are developed and used to show very good agreement with the analytical result.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1628-1632
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• 1994

KEPCO is now promoting the new project of upgrading its highest system voltage from 345kV to 765kV. The main reason of this project is an insurance of bulk power transmission from power complexes at coast to power demand center at Kyoung-In area. The new system needs a careful approach to basic design to secure its reliability and to reduce the increase of investment cost. So, We introduced the basic philosophy of insulation design in spring meeting of this transaction. This paper, after preceding paper, deals with the insulation design example for 765kV transmission lines.

• 대한기계학회논문집
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• 제14권3호
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• pp.594-602
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• 1990

본 연구에서는 동력전달용 인벌류우트 원통치차(스퍼어 및 헬리컬 기어)의 강 도 및 각종 영향인자를 충분히 고려하면서 크기를 최소로 하는 치차장치의 설계법을 개발하고, 이 설계법을 기본으로 하여 퍼스널 컴퓨터 상에서 누구나 손쉽게 설계에 이 용할 수 있는 설계 시스템을 개발하여 그 평가를 수행한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.234-236
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• 2004

Transmission control protocol(TCP) is protocol used in internet. TCP is seldom transmission error and is protocol based on wire environment. TCP uses 3 way handshake ways, data transmission control through windows size, data transmission control through reception confirmation, sliding window for packet delivery. In this study, designed TCP packet ion module for analyze the TCP segments & correct information about TCP. TCP capture in internet using designed TCP module and analysed TCP segments composition. Through this, could analyze the correct information of protocol in network.

• 기술사
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• 제34권4호
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• pp.30-35
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• 2001

The 8-VSB modulation technology developed by ATSC was adapted for national terrestrial DTV broadcasting. It uses same bandwidth of 6㎒ as the one of NTSC TV broadcasting. The simulcast on the both of analog and digital is mandated for some period, some shortage within the limited frequency resource . ATSC transmission technology is excellent in long distance broadcasting, but it is even poorer than other transmission technology In mobile receiving. The design of transmission system in the ATSC broadcasting is food enough with the provision of wide area service without Interference from adjacent channel. To provide adequate DTV service within the broadcasting area, transmission technology is an important factor

• 한국정밀공학회지
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• 제15권10호
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• pp.120-127
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• 1998

In this study the dynamic characteristics of automatic transmission system due to the change of the planetary gear ratio is studied. To study the power flow and shift quality for power transmission the simulation program is developed using the modeling and analysis technique. The results from this study will be used in designing the basic structure of automatic transmission using planetary gear system.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.257-264
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• 1998

Sound transmission characteristics are investigated on the corrugated panels which used for railway vehicles. A special purpose program is developed to calculate the sound transmission loss of orthotropic multi-layered panels. Several kinds of corrugated panels are analysed to estimate the transmission performance and the results are compared with the measured data. Calculated transmission losses show good agreement with the measured values in corrugated panels and aluminum/foam multi-layered panels. The analysis results can be utilized to design the corrugated panels and multi-layered panels which are required to reduce the interior noise in railway vehicles.

• Tribology and Lubricants
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• 제21권2호
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• pp.93-99
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• 2005

The fault of an automobile transmission gear occurs whenever moving tooth surfaces interact. Such a failure condition has an effect on the frictional factors such as applied load, sliding speed, frictional time and gear oil. However, it is difficult to know the mutual relation of these factors. In this study, the friction and wear tests were carried out to get the friction characteristics with carburized SCM420 and nitrocarburized NT100 have being used as automobile transmission gear materials. And it was undertaken to analyze the frictional factors that have effect on frictional characteristics by using design of experiment. From this study, the result showed that the applied load in frictional factors was the most important, next to frictional time, sliding speed. And the friction characteristics of nitrocarburized NT100 was more excellent than carburized SCM420.