• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.704-708
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• 2004

Recently, many nation have released standard such as IEC 61000-3-2 and IEEE 59, which impose a limit on the harmonic current drawn by equipment connected to AC line in order to prevent the distortion of an AC Line. Therefore, Plasma Display Panel (PDP) which is highlightened in digital display device also has the Power Factor Correction (PFC) circuit to meet the harmonic requirements. In PDP power module, the conventional boost converter is usually used for the PFC circuit. However, it comes serious thermal problem on it's bridge diode due to heat of PDP, and therefore the system stability is not guaranteed. In this paper, the bridgeless boost converter, which is used for PFC circuit of the PDP power module, is designed and verified the possibility of the application in a practical product in a view of efficiency, component count, temperature and etc.

• Journal of Information Display
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• 제10권1호
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• pp.24-27
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• 2009

A simple nonalkoxide sol-gel route for depositing an Al-doped ZnO thin film on a glass substrate was derived in this study. The initial Al dopant concentration in the sol-gel preparation varied and ranged from 0 to 5%. The sol-gel-derived thin films showed c-plane preferred crystallization of their hexagonal phase, with nanosized grain structures. First and second post-heat-treatments were carried out to improve the film’s electrical resistivity. The carrier density and the Hall mobility were measured and discussed to explain the electrical resistivity. The optical transmittance within the visible range showed compatible properties, which indicates the possible use of A1-doped ZnO as a transparent electrode in flat panel displays.

• Journal of Advanced Marine Engineering and Technology
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• 제17권4호
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• pp.1-10
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• 1993

This paper introduces the outline of hull structure to the sorts of LNG carrier briefly. Especially, explains in detail for the insulation system of Moss Rosenberg Verft spherical tank type LNG carrier. It is not easy task to calculate exactly the temperature distribution of hull because of very complicated structure of hull. Therefore, in this paper by the adequate modeling of the Moss Rosengerg spherical tank type LNG carrier, a program is developed which calculate the temperature distribution of every hull and estimate the heat influx from every hull and output the BOR according to the variation of atmospheric conditions on boyage.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1407-1411
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• 2003

Due to the heat confinement in the shallow region of the target for a short time scale, pulsed laser annealing has received increasing interest for the fabrication of poly-Si thin film transistors(TFTs) on glass as a low cost substrate in the flat panel displays. The formation and growth mechanisms of poly silicon(poly-Si) grains in thin films are investigated using an excimer laser crystallization system. To understand the crystallization mechanism, the grain formations are observed by FESEM analysis. The optical reflectance and transmittance during the crystallization process are measured using HeNe laser optics. A two-step ELC(Excimer Laser Crystallization) process is applied to enhance the grain formation uniformity.

• 한국레이저가공학회지
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• 제6권2호
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• pp.9-17
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• 2003

Due to the heat confinement in the shallow region of the target for a short time scale, pulsed laser annealing has received an increasing interest for the fabrication of poly-Si thin film transistors(TFTs) on glass as a low cost substrate in the flat panel displays. The formation and growth mechanisms of poly silicon(poly-Si) grains in thin films are investigated using an excimer laser crystallization system. To understand the crystallization mechanism, the grain formations are observed by FESEM photography. The optical reflectance and transmittance during the crystallization process are measured using HeNe laser optics. A two-step ELC(Excimer Laser Crystallization) process is applied to enhance the grain formation uniformity.

• Journal of Advanced Marine Engineering and Technology
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• 제11권1호
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• pp.63-71
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• 1987

The measuring of acoustic intensity has been investigated by many researchers and practicians during the last several decades. But due to the lack of measurement accuracy, they have had no practical use. In recent years, the two microphone acoustic intensity method has been developed by the advancement of FFT analysis technique and the digital data processing equipment. This new method of using two microphones gives informations on the noise source survey and the acoustic power of sound radiation source without the anechoic room. In this paper, theoretical formulae for the two microphone acoustic intensity method and the sound transmission loss are checked. The obtained results for the acoustical enclosure of gas heat pump were compared with the classical field incidence mass law. The surface vibration modes for a panel of enclosure were also estimated.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.149-150
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• 2018

Recently, a large fire has occurred through a dry bit, which is a flammable exterior material, in Daebong Green Apartment Fire in Uijeongbu in 2015 and Jecheon Sports Center Fire in 2017. In this study, KS F ISO 5660-1 Cone calorimeter experiment was used to examine the fire risk of dry bit. Also, the performance of the repair and reinforcement materials to prevent fire expansion was examined. As a result, the dry bit is likely to be ignited by internal and external flower gardens, and its combustion rate and calorific value are very high. In addition, the performance of heat resistance such as ALC panel and ceramic board as a repair and reinforcement material has been proved. However, the insulation is expected to require further consideration.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.21-22
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• 2018

Foamed concrete is a porous concrete that is cured by mixing bubbles into cement slurry. It is lighter than ordinary concrete and is characterized by higher insulation. Lightweight foamed concerte is mainly used as a sandwich panel in Korea, and is also used as a refractory filler in fireproof safes. Studies on lightwight foamed concrete have been carried out on strength,density and thermal conductivity. However, it is confirmed that the research on the fire resistance performance is very limited. Based on this study, fire resistance of lightweight foamed concrete using expanded polystyrene beads is investigated.

• 한국태양에너지학회 논문집
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• 제22권2호
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• pp.11-17
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• 2002

This paper is concerned with the development of a new method for making, separating ice and storage floated ice by installing an evaporation plate at under-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating an ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. Developed new harvest-type method shows good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, however these components are not necessary in a new method. In this study ice storage systems are experimentally investigated to study the charge and discharge of thermal energy. The results show the applicable possibility and performance enhancement of a new type.

• 대한조선학회 특별논문집
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• 대한조선학회 2008년도 특별논문집
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• pp.112-117
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• 2008

The Insulation, which is consist of the glass wool, mineral wool or perforated SUS plate, installed on the wall or under ceiling for the protecting heat and the blocking the noise of engine room area. In our shipyard, designing the structure model of insulation is hard and difficult, Because designed the insulation model is considered of any factors which are hull model properties of panel shape, direction and thickness and service of area. In this paper, We issue the way to utilize shape and direction of the hull model information and specific character of working space in engine room.