• 한국분무공학회지
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• 제9권4호
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• pp.77-82
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• 2004

This paper describes the improvement of engine cooling system. To improve engine cooling performance, the authors approached in two ways. One is to increase water pump performance, changing of impeller shape and lightening of material were carried out. The second one is cooling efficiency rise, which were investigated with head gasket coolant flow passage optimization with flow visualization technique. The test results show that water pump performance was increased effectively, reduction of pump drive torque, and increase of pump flow-rate and pressure rise. Gasket hole pattern optimization test results represent an optimized head coolant flow which stands cross flow from exhaust to intake port side and small vortex were removed.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.764-765
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• 2017

발사체 경량화에 따른 한국형발사체 발사성능 해석을 위해 3 자유도 모델을 이용한 궤적계산 프로그램을 작성하였다. 이를 이용하여 단 별 구조비 감소에 따른 태양동기궤도 투입성능을 추정하였으며, 성능 지표는 투입 가능한 탑재체 무게를 기준으로 하였다. 구조비를 Angara 로켓과 유사한 수준까지 경량화 할 경우 목표 궤도에 2.58 ton을 투입할 수 있을 것으로 보인다.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 춘계학술발표대회 논문집
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• pp.263-266
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• 2005

This work aims at the design of the artwork for the atrium of a furniture department store. In complying with the request of the building owner I have established the basic concept, 'silence in movement - movement in silence', to design a artwork, which not only can make the various atmospheres in the store to the unique one, but also arrange an emotional stability for the visitors. Most exhibited furnitures are those that demand particular interests from the visitors, and the exhibition scale is enormous. So it is difficult to sustain the continuous inspiration and the emotional stability, and also it is hard to make the store have the consequent image. This problem can be resolved through the installation of the artwork that can evoke the visitor to the abundant sensitive receivability. The materials, which are used tp express the basic concept, are water, concrete, light and aluminium that represent a unified harmony in a contrast each other.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.546-549
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• 2004

This paper describes the electrical characteristics of the polymer lightning arresters(L.As) used to protect distribution lines and power facilities from surge. For the relative comparison, the characteristics assessment was done for 2 states of L.As before and after water immersion treatment. The L.As for the comparative test were immersed with water of $95[^{\circ}C]$ considered a severe condition. After the immersion treatment, the assessment was carried out for material analyses in chemical structure(FTIR : fourier transform infrared spectrophotometer). Electrical performance measured insulation resistance measurement, leakage current measurement, critical operation voltage measurement etc.. In addition to, the results were compared with those for the L.As deteriorated in the field. Thus, the accelerative deterioration degree of polymer materials by immersion treatment was evaluated, by which the structural defects of the polymer L.As could be inferred.

• 조명전기설비학회논문지
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• 제28권7호
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• pp.69-74
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• 2014

Recently, IEC published new standards about the requirements and tests for lightning protection system(LPS) components. If components are used for LPS, they should comply with the IEC standards. This paper, we collected six specimens for the metallic connection components using in domestic, and it tested for withstand lightning current which according to the IEC 62561-1. As a result, only one specimen meet this performance requirement. The specimen is the metallic connection component with four bolts fixed. Therefor, when designing of LPS in domestic, the metallic connection components shall be taken into account for the selection of the withstand lightning current. In addition, we need to develop for LPS components product and the national standards.

• 조명전기설비학회논문지
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• 제29권2호
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• pp.91-96
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• 2015

There are provision for risk analysis in IEC standards. It is to determine the need for installation of a surge protection device (SPD) in order to protect the low-voltage electrical installations from overvoltages caused by atmospheric phenomena and the like. However, scattered many related standards, the lack of details are not easy to apply it in the field. We investigated the relevant domestic and international standards for applies to the international standards in domestic. And we proposed the flow chart for determining the need for protection of the low-voltage electrical installations from overvoltage due to atmospheric phenomena and it set the appling target facility.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.621-623
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• 1993

This paper describes the research in condenser cone of sealing-end for 154kV oil-filled underground cable. We conducted the design based on the results of electric field analysis by electrostatics theory and FEM. In case that condenser cone type EB-A was compared with bell mouth type EB-A, the results of the AC and lightening impulse voltage test showed improvment of 10 percents.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.566-568
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• 1993

A measuring technique for the fast transient high voltage is under development by use of laser source in order to substitute for the conventional measuring system which could bring about several technical inconveniences. At this moment, this work is aimed to construct a compact measuring system with the use of Pockels cell and specially designed voltage divider. This system is likely to enable us to measure the lightening impulse voltages at the level of 30kV, 50kV and 70kV. Throughout this work, qualified measuring devices are required to be developed for discriminating different kinds of noise from which the system should be protected.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2007년도 Proceedings of The Convention
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• pp.117-126
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• 2007

Cosmetics have mild activity on the human body, and intended to be used for cleaning, beautifying the human body, and also keeping healthy skin or hair, promoting attractiveness or altering the appearance. Functional cosmetics, in other words cosmeceuticals, are restricted for following functions: 1) Whiten the skin tone by preventing deposition of melanin pigmentation or lightening of the color of melanin of skin, 2) alleviate or improve wrinkles of the skin, and 3) protect the skin from the ultra violet rays from the sun. According to the functions of the functional cosmetics, skin whitening products, anti-wrinkle products, and suntan & sunscreen products are manufactured. In order to manufacture and import the functional cosmetics in Korea, the approval process in KFDA is necessary. The review process in KFDA is performed based on The Korea Food and Drug Administration Notification 2007-44, "The Regulation of Reviewing the Functional Cosmetics" (June 29, 2007). Only after the approval of KFDA, functional cosmetics are allowed to advertise to the consumers for their functionality.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.345-352
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• 1998

The dynamic analysis of a train system has tended to analyze one vehicle or subsystem of that rather than to analyze entire vehicles. But, the speeding and lightening of a train requires more accurate analysis. Thus, the analysis of entire vehicles is required but it spends much time. Therefore, it is needed to find out the new analytic method which is more accurate and efficient. This paper suggests a new method for analyzing a multi-vehicle system more efficiently, using‘mechanical impedance’At first, get the impedance of vehicles which influence the dynamics of the object car, through analyzing the dynamics of a vehicle. ‘Equivalent system’, a simple mechanical system, of which the impedance is similar to that ,is proposed. Then, the equivalent system was applied to a vehicle and it showed that the equivalent system works like a real vehicle system. Finally, we tried non-linear analysis of a vehicle to which the equivalent system is applied.