• 한국군사과학기술학회지
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• 제25권4호
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• pp.355-363
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• 2022

Development of supersonic flying vehicle is one of the most latest issue in modern military technology. Specifically, structural integrity of supersonic flying vehicle can be verified by high temperature structural test. High temperature structural test is required to consider thermal load caused by aerodynamic heating while applying structural load simultaneously. Tubular quartz lamps are generally used to generate thermal load by emitting infrared radiation. In this study, modified heat flux model of tubular quartz lamp is proposed based on existing model. Parameters of the proposed model are optimized upon measured heat flux in three dimensions. Finally, thermal load of plate specimen is designed by the heat flux model. In conclusion, it is possible to predict heat flux applied on plate specimen and desired thermal load of high temperature structural test can be obtained.

• Journal of Oral Medicine and Pain
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• 제31권1호
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• pp.47-57
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• 2006

본 연구는, 표면열요법 중에서 널리 쓰이는 습열 요법(온습포)과 건열 요법(적외선 램프)이 전이부 표층부 혈류량과 피부온도에 미치는 영향을 평가하기 위해, 건강한 성인 20명(남 10명, 여 10명)을 대상으로 laser doppler flowmetry를 사용하여 표면열요법 적용전후의 피부 온도와 표층부 혈류량을 측정함으로써 다음과 같은 결과를 얻었다. 1. 온습포와 적외선 램프 모두에서 표층부 혈류량과 피부 온도는 적용전보다 적용후에 유의하게 증가하였다. 2. 표면열 요법 적용 후 표면 온도는 표면열 요법 적용 직후에, 표층부 혈류량은 표면열 요법 적용 4분 후에 가장 높게 나타났으며, 그 이후 꾸준히 감소하였다. 3. 표면열 요법 적용 후 증가된 표층부 혈류량은 적외선 램프에 비해 온습포에서 더 오랫동안 유지되었다. 4. 표면열 요법 적용 후 증가된 피부 온도는 두 요법 모두 60분간 유의성있게 증가된 상태로 유지되었으나, 적외선 램프 적용 후 증가된 피부 온도는 온습포에 비해 급격히 감소하였다. 5. 적외선 램프 적용 직후 여성이 남성보다 표층부 혈류량의 증가가 컸으나, 그 이후 차이가 점차 감소하여 20분 이후에는 성별에 따른 차이가 없었다.

• 전기학회논문지
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• 제56권7호
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• pp.1261-1267
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• 2007

Although LEDs have been used in various applications with improving the brightness and luminous efficacy, the electrical and optical characteristics of high power LED varies at different temperature and starting time. In this paper, optimal heat sink and apparatus design were conducted using IR camera and ICEPAK on the LED bulb consisting with fourteen LED array. The temperatures of heat sink and LED device of the designed LED bulb without cooling pan were $74^{\circ}C\;and\;96.8^{\circ}C$, respectively, showing in good themal characteristics. For high efficiency driving circuit of LED array adopted optimal heat sink design, driving circuits of constant voltage and current circuits were suggested and fabricated. As a result the efficacy of all driving circuits showed more than 20 lm/W. Also, the constant current circuits are suitable for signal lamp, hallway lamp, and flash lamp having short operating time(about 30 min). On the other hand, a reading light and indoor lamp having long operating time can be controlled by constant voltage circuit.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2012년도 전기공동학술대회 논문집
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• pp.130-132
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• 2012

In this paper, a temperature control for LED(Light Emitting Diode) lamp using a cooling fan is studied. An efficient temperature control scheme for the LED lamp using the fan wind at the lowest sound noise is studied. For the study, after measurement of the minimum sound noise of the fan and related temperature of the LED lamp through tests, experiments on temperature control of the LED lamp using the fan with various size of heat sinks was performed. To minimize the fan sound noise, optimal size of the heat sink was studied. Also, a teleoperting control of LED lamps using RF communication was studied.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.263-266
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• 1987

Generally an incandescent lamp is made in the bulb with a horizontal position filament. In this paper the position of filament was changed Into a vortical position. When the position of filament is changed into a vertical position, efficacy is increased and color rendering is somewhat improved. In this subject the heat loss by a filling gas is important. The heat loss by a filling gas was calculated theoretically. The results in an Incandescent lamp experiment can be analyzed through the heat loss by a filling gas. As a filling gas the mixture of argon and nitrogen is used. The variation of lamp characteristics by the shape of filament rill be considered. The change by filament position to a vortical position is required in the field of power consumption saving of lighting system.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.18.2-18.2
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• 2005

• 한국기계가공학회지
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• 제17권6호
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• pp.117-123
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• 2018

Automotive headlamps have been continuously developed as one of the most important devices for securing the driver's view, and the LED lamps are getting popular in recent years. However, in case of the LED lamps, because the heat generated by the LED lamps are too high, it shorten the product life and lower the LED efficiency. Therefore, this study was investigated the cooling characteristics of the LED lamp heat sink for automobile by forced convection for LED heat generation control. In order to analyze the cooling characteristics of the heat sink, the temperature distribution results were investigated through the experiment and computational analysis under the increase of the air flow velocity, and the convective heat transfer coefficient was obtained. Also, convective heat transfer coefficient was calculated by the theoretical formula under the same condition and compared with experimental and computational results. From the result of this study, as the air flow velocity around the heat sink fins increased, the convective heat transfer coefficient significantly increased, confirming the improvement in the cooling effect.

• 한국군사과학기술학회지
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• 제11권2호
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• pp.136-143
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• 2008

A three-wavelength solar bank is a very important part for a solar simulator with commercial superlux lamps. It is projected metal halide lamps to satisfy following points simultaneously: $\pm$10% of uniformity for irradiance of target area and irradiance in each wave region, and $1,232W/m^2$ of maximum solar irradiance in summer. The developed solar lamp bank has been analyzed numerically by commercial programs in this study to carry out experiments. In conclusion, designed B-type heat lamp is not concentrated in one place than designed A-type heat lamp, it is spreaded widely, and it was proved numerical computation. We suggest that solar simulator is applied to actual experiment test through heat flow numerical analysis in solar lamp bank and the lamp is applied private industry or the military using complex environmental assessment test.

• KIEAE Journal
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• 제10권6호
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• pp.27-32
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• 2010

Approximately 20 percentage of energy consumptions in buildings is consumed as lighting energy. Thus, most of the corporations of lighting fixture have launched low energy products. However, many researchers focused on the only luminous efficacy for energy conservation and used the evaluating tool of study. This can not gauge the precise cooling load related on generated heat of artificial lighting. In order to assess an effect of the temperature variation of lighting resources, the main purpose of this study is to predict the generated heating energy from lighting by measuring the thermal variation in scale model to reduce external noise. Also this paper used MX100 data logger to record at an interval of 1 minute for 60 minutes for the temperature of interior lightings such as incandescent lamp, fluorescent light, halogen lamp and LED lamp. As a result, LED lamp generated the lowest heat. On the other hand, incandescent lamp did the highest.

• 한국태양에너지학회 논문집
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• 제32권5호
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• pp.102-107
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• 2012

Halogen lamp was applied to fabricate the selective emitter crystalline silicon solar cell. In selective emitter structure, the recombination of minority carriers is reduced with heavily doped emitter under metal grid, consequently improving the conversion efficiency. Laser selective emitter process which is recently used the most generally induces the damage on the silicon surface. However the lamp has enough heat to form heavily doped emitter layer by diffusing phosphorus from PSG without surface damage. In this work, we have studied to find the design and the suitable condition for halogen lamp such as power, time, temperature and figured out the possibility to fabricate the selective emitter silicon solar cell by lamp heating. The sheet resistance with $100{\Omega}/{\Box}$ was lower to $50{\Omega}/{\Box}$ after halogen lamp treatment. Heat transfer to lightly doped emitter region was blocked by using the shadow mask.