• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1649-1652
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• 2005

Line constants are composed by impedances and susceptances. We don't need all line constants on electric railway system. Depending on where they are applied, The algorithm to get line constants Is different. We suggest two algorithm to measure them.

• 대한전기학회논문지:전력기술부문A
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• 제53권8호
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• pp.421-431
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• 2004

Line constants are composed by impedances and susceptances. A paper which was published estimated only impedances of line constants. Therefore, this paper estimates susceptances as well as impedances of equivalent five-conductors model using the reduced equivalent method. In order to verify estimated line constants, we measured line constants of real railway system. And we compared calculated results with measured data on 60Hz∼3000Hz. For the other verification, the calculation results from the proposed model and the measurement data from the test are compared focused on the amplification of harmonic current in the paper.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.613-619
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• 2000

This paper presents a mettled to reduce the number of conductors of catenary system for estimating line constants. Conductors of a catenary system are grouped and reduced. For example, the model representing the contact and the messenger conductors with a single equivalent conductor is. probably more realistic than assuming the two conductors completely separated, since they are generally connected by droppers every few meters. Therefore, this paper shows the method to reduce the number of conductors using electric circuit theory. To verify the results, we compared the equivalent line constants obtained by proposed method with those obtained by measurement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.275-277
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• 2004

when a fault occurs, we need the fault locator to find out the location of the fault quickly. The fault locator can find out the exact location of the fault through the line constants of the catenary system. If the configuration of the catenary system is modified, the line constants is also changed. Therefore, this paper analyzes the error of the operation of the fault locator by the simulation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.443-445
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• 2001

This paper describes an estimate of line constants using the five-conductors equivalent model. Actually, a catenary system is composed of the five-conductors equivalent model. Therefore, we made up the five conductors equivalent model of a catenary system by applying a method of inverse matrix. Finally, we estimated line constants using the five-conductors equivalent model. To verify the results, we compared estimated line constants with measured those.

• 대한전기학회논문지:전력기술부문A
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• 제52권12호
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• pp.684-690
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• 2003

This paper estimates line constants of equivalent five-conductors model using the reduced equivalent method. Actually, the catenary system is considered by the equivalent five-conductors model in the electrical aspect. Therefore, we should compose the catenary system of the equivalent five-conductors model, then the line constants of this equivalent five-conductors model are calculated. This paper shows the reducing process about the real system of the field by using the proposed theory. Also the line constants of reduced system are provided in this paper.

• 한국음향학회지
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• 제19권5호
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• pp.41-45
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• 2000

단결정 초격자 다층박막의 유효탄성계수를 표면탄성파 전파속도에 근거하는 두 가지 방법에 의하여 결정하였다. 첫째 방법은 구성층의 탄성계수로부터 초격자의 유효탄성계수를 계산하는 공식을 사용한다. 계산된 유효탄성계수로 계산한 기판 위 박막의 표면탄성파 전파속도와 선집속 초음파현미경으로 측정한 표면탄성파 전파속도를 비교하여 그 유효탄성계수를 검증한다. 둘째 방법은 선집속 초음파현미경으로 측정한 표면탄성파 전파속도 분산 데이터로부터 역산하여 초격자 다층박막의 유효탄성계수를 결정한다. 두 가지 방법을 TiN/NbN 초격자 다층박막에 적용하여 서로 잘 일치하는 결과를 얻었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.415-420
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• 2003

This paper estimates line constants of equivalent five-conductors model by using the reduced equivalent method. Actually, the catenary system is considered by the equivalent five-conductors model in the electrical aspect. Therefore, we should compose the catenary system of the equivalent five-conductors model. And then we calculate line constants of this equivalent five-conductors model. This paper shows the reducing process about the real system of the field by using the proposed theory and also line constants of reduced system

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1524-1526
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• 2005

This paper describes the measurement and analysis of the basic line constants in PLC(Power Line Communication) in the residential building. An apartment is considered as one of the conventional residences to get the line constants in this paper and Agilent 4263B LCR Meter is used to measure the detailed values each area and the specific results and the averaged analysis data are shown in the tables. The measured results no different from the calculated values with using conventional formula due to the line arrangement neglected factors, complex permittivity, and etc. Also, this paper describes many kinds of lines and wiring figures of domestic construction. Finally, it is utilized with the analyzed line characteristics in frequency domain as a planning reference of PLC.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.267-270
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• 2002

It is very important to analyze the superconducting power cables by the modeling for correct and reasonable cable design suitable for the domestic situation of power systems. This paper describes the basic modeling for superconducting power cables using ATPDraw. And also it is shown the line constants of cold dielectric coaxial type which is one of the HTS cables. It is compared with the line constants of general two kinds of power cables(OF, XLPE).