• Journal of Astronomy and Space Sciences
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• 제15권2호
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• pp.391-400
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• 1998

KSR-II, a two-stage sounding rocket of KARI was launched successfully at the west coast of the Korean Peninsula at 1000LST, June 11, 1998. For the ozone measurement mission, 8-channel UV and visible radiometers were onboard the rocket. The rocket measured the first in situ stratospheric and mesospheric ozone density profile over Korea during its ascending phase using the radiometer. Comparisons with Dobson spectrophotometer, ozonesonde, and HALOE onboard the UARS are shown together. Our results are in reasonable agreements with others.

• 한국응용과학기술학회지
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• 제26권2호
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• pp.213-223
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• 2009

Conventional additives were added to a newly synthesized base oil to create synthetic lubricants. Commercial polyol ester prepared in this laboratory were obtained as esterification of 1,1,1-trimethylol propane and respectively. This newly synthesized base oil had a variable chemical structure that could achieved the following properties; oxidation or thermal stability, low temperature fluidity, and higher flash points. When compared with commercial mineral lubricants, the synthetic lubricants show superior thermal and oxidation stability, and anti-wear properties.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.274-275
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• 2006

The IEEE std 738 and Cigre Electra documents are well known as the standard of calculating the ampacity of overhead conductors. Although these two standards use the same basic heat balance concept, they use different applicable methods to calculate ampacity ratings. This paper examines the concept of basic heat balance equation and the differences of each term of basic heat balance equation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.709-711
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• 2005

Developing fault location system for underground power cable which can detect its fault location exactly require very high speed data acquisition and signal processing capability. We are developing fault location system which is different from conventional fault locator. This fault location system monitor underground power cable by using on-line speed current sensor and if there are an accident, it record its transient signal and calculate fault location by analyzing it. Signals which acquired when power cable fault arise, showed transient characteristics and its frequency band is very hish. So, to develop fault location system, we designed special high speed data acquisition and signal processing board. In this thesis, we describe on data acquisition and signal processing H/W design for fault location system on underground power cable.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.347-349
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• 2005

This paper presents the results of an investigation and assessment of the direct short term impacts of electric service interruption incurred by livestock customers. The study used a direct visit survey to determine the customer assessment of electric service interruption and characteristic. The variation in interruption cost with the characteristics of interruptions such as duration, time of day, frequency, and day of interruption was also investigated.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.89-90
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• 2006

As the power industry moves towards open competition, there has been a call for methodology to evaluate power system reliability by using customer interruption costs. This paper presents an evaluation of interruption costs by industrial customer type in Korea using customer survey methodology When various research results are examined, the customer damage survey methodology becomes much more generalized. Especially, in the case of industrial customers, it is known that the evaluation by customer damage survey is more useful. Accordingly, this paper selected the customer damage survey method to evaluate interruption costs by industrial customer type in Korea considering interruption and customer characteristics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.350-352
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• 2005

This paper presents the results of an investigation and assessment of the direct short term impacts of electric service interruption incurred by public customers. The study used a direct visit survey to determine the customer assessment of electric service interruption and characteristic. The variation in interruption cost with the characteristics of interruptions such as duration, time of day, frequency, and day of interruption was also investigated.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.396-398
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• 2005

IEC 60287-3-2 standards suggests the selection method of economic conductor size for power cables. This method deals solely with the economic choice of conductor size based on joule losses. This paper introduces the method and example study which is proposed by IEC standards.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.399-401
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• 2005

When power cables cross regions with unfavorable thermal conditions, conductor temperatures higher than the design value can occur. This paper proposes the calculation algorithms of the permissible current-carrying capability of dissimilar power cables installed in thermally dissimilar soil materials.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.647-649
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• 2005

가공배전계통의 주상변압기에는 직격뢰나 유도뢰에 의해 고압측이나 저압측으로부터 뇌과전압이 침입할 수 있고. 이러한 경우 침입단은 물론, 상대단에도 과전압이 나타날 수 있어, 주상변압기 자체와 고압 및 저압계통에 영향을 미치게 되므로, 주상변압기의 뇌과전압 전달특성을 파악하는 것은 절연설계와 절연협조에 있어 매우 중요한 자료가 된다. 본 논문에서는 실제 선로와 같은 구성과 규모의 실증 배전선로에서, 주상변압기에 임펄스전압이 침입한 경우의 변압기 양단에 나타나는 과전압에 패한 실증결과의 예를 소개하였다.