• 한국광학회지
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• 제13권6호
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• pp.559-563
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• 2002

본 논문에서는 직접 고안한 scanned point-detecting system(SPDS)을 이용하여 PDP 방전 셀 내에서 방출되는 광을 3차원 적으로 시간 분해하여 측정하였다. PM tube를 통해 검출된 광 신호를 오실로스코프 상에서 파형을 확인하고 PC제어를 통해 결과를 얻었다. Ne-Xe(4%) 혼합가스가 400 ton압력으로 채워진 패널에서 측정한 시간 분해 결과를 살펴보면 패널의 전면판(top view)에서는 방전이 cathode전극의 안쪽 edge에서 시작되면서 cathode전극 바깥쪽으로 호의 형태를 이루면서 진행되는 것을 알 수 있었으며 패널의 측면(side view)에서 측정한 시간 분해 결과를 살펴보면 약 150$\mu\textrm{m}$의 높이까지 방전에 의한 광이 검출되었다. 그리고 구동전압 펄스가 인가된 후 730 ns에서 가장 큰 intensity가 나타났다.

• Journal of Welding and Joining
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• 제19권4호
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• pp.371-374
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• 2001

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.483-488
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• 2006

In this study, newly-developed slim electronic panel cooler with aluminum PF condenser and evaporator was tested and the results are compared with imported panel cooler with fin-tube heat exchangers. The PF heat exchangers significantly (approximately 45%) reduced the refrigerant charge. The air-side pressure drop was also reduced, which resulted in the reduction of the sound level of the panel cooler. The effect of the condenser size was also investigated.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권10호
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• pp.476-480
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• 2003

In this paper, we have performed 3-dimensional time-resolving measurement of the Ne light emitted from the cell of plasma display panel(PDP) as a function of the pressure using the scanned point detecting system. From the temporal behavior results, we could analyze the discharge behavior of panel with Ne-Xe(4%) mixing gas and 300 torr, 400 torr and 500 torr pressure. At the top view of panel, the discharge of 300 torr panel starts at the 634 ns and ends at the 722 ns. The emission duration time is about 90 ns. The discharge of 400 torr panel starts at the 682 ns and ends at the 786 ns. the emission duration time is about 100 ns. Also, the discharge of 500 torr panel starts at the 770 ns and ends at the 826 ns. the emission duration time is about 56 ns. The discharge moves from inner edge of cathode electrode to outer cathode electrode forming arc type. In the side view of 300 torr, 400 torr and 500 torr an emission shows that the light is detected up to 180${\mu}{\textrm}{m}$, 150${\mu}{\textrm}{m}$ and 70${\mu}{\textrm}{m}$ height of barrier rib and the emission distribution of the 300 torr is wider than 400 torr, 500 torr.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.457-462
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• 2009

In a high speed train, aluminium extruded panel is widely used in floor, side wall and roof structures for high bending stiffness and weight reduction. However, with some inevitable reasons, aluminium extruded panel shows inferior sound insulation performance compared with the flat panel having same weight. Especially, occurrence of local resonance modes in the particular frequency band, is one of the main reason in the deterioration of the sound insulation performance. Local resonance modes are generated in the structure which consists of periodic unit structure, such as the aluminium extruded panel. The local resonance frequency is determined by the specification of the unit structure. In this study, we predict the local resonance frequency band on the aluminium extruded panel used for the high speed train, and investigate how the design modification in the unit structure influences the local resonance frequency band and panel bending stiffness. The purpose of the study is to provide the design information for the effective unit structure in order to improve the sound insulation performance of the aluminium extruded panel.

• 설비공학논문집
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• 제25권8호
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• pp.471-476
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• 2013

The present study has been carried out to elucidate the optimal method for the performance test of a refrigerator vacuum insulation panel (VIP), by using numerical heat transfer analysis. Three locations of heat flux meter have been tested, for deriving the best test method to clarify the normal or the abnormal condition of the vacuum insulation panel in a refrigerator. The first location of the heat flux sensor is at the same place as the heater, the second one is at the nearby side location of the heater and the third one is at the opposite side location of heater in the refrigerator. The heat flux and $1/q^{{\prime}{\prime}^2}$ or $q^{{\prime}{\prime}^4}$ were calculated for the cases with the normal VIP, and with the abnormal VIP, and their differences analyzed. From the present study, the first and the second method had a mere difference characteristics of heat flux and $1/q^{{\prime}{\prime}^2}$ or $q^{{\prime}{\prime}^4}$, between the cases with the normal or the abnormal VIP. The magnitude of the heat flux after 300sec had a great difference between the cases with the normal or abnormal VIP for the third method, and it could be considered the most optimal method to test the performance of a refrigerator vacuum insulation panel.

• Journal of Power Electronics
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• 제5권1호
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• pp.67-75
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• 2005

A high efficiency ZVS PWM asymmetrical half bridge converter for a plasma display panel (PDP) sustaining power modules is proposed in this paper. To achieve the ZVS of power switches for the wide load range, a small additional inductor L/sub 1kg/, which also acts as an output filter inductor, is serially inserted into the transformer's primary side. At that point, to solve the problem of ringing in the secondary rectifier caused by L/sub 1kg/, the proposed circuit employs a structure without the output filter inductor, which helps the voltages across rectifier diodes to be clamped at the output voltage. Therefore, no dissipative RC (resistor capacitor) snubber for rectifier diodes is needed and a high efficiency as well as low noise output voltage can be realized. In addition, since it has no large output inductor filter, the asymmetrical half bridge converter features a simpler structure, lower cost, less mass, and lighter weight. In addition, since all energy stored in L/sub 1kg/ is transferred to the output side, the circulating energy problem can be effectively solved. The operational principle, theoretical analysis, and design considerations are presented. To confirm the operation, validity, and features of the proposed circuit, experimental results from a 425W, 385Vdc/170Vdc prototype are presented.

• 한국생산제조학회지
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• 제21권2호
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• pp.259-266
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• 2012

In this study, the temperature distributions are analyzed on the air flow according to the position of fan inside computer main frame by CFD simulation. In case that ventilation hole is existed at the side of computer frame, the air with lower temperature can be circulated near CPU radiant thermal panel. In case of installation with fan at the side panel, the temperature of air flow becomes lowest. The efficiency of thermal emission at personal computer and its durability can be improved by releasing a lot of heat at air flow effectively inside computer frame according to this simulation result.

• 한국자동차공학회논문집
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• 제10권4호
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• pp.141-148
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• 2002

Repair were made for front pillar, center pillar and side-step panel for lightweight vehicles with head-on and 40% off-set collision of 15 km/h in a RCAR standard. The salt dilution was sprayed and the compression tests were performed for vehicles with and without anti-corrosional treatment after repair. After 764 hours of salt-dilt sprayed test without using anti-corrosion, the mean penetration depth fur corrosion was shown to be 58% of the thickness. The resulyed decrease in bending stiffness by 10∼20% can cause reduction of the residual life and crash-absorption capability for damaged vehicles. The corrosoin safety tests showed that the anti-corrosional treatment should be made to improve the safety characteristics for a or damaged car.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.161-164
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• 1999

In order to investigate the effect of punching condition on the stretch flange formability of sheet for deep drawing hole expansion tests at various edge condition were done. Edge conditions were changed by altering tool clearances artifical defects grinding and deburring. For a determination of optimum edge condition of side panel of automobile punched section analysis and forming results were studied and the laboratory test results were used. In case of considered side panel tool clearance should be less than 15% and punched edge should be uniform without defects for safe forming