• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.112-112
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• 2000

직접 천이형 물질인 GaN는 그 연구가 활발히 진행되어 청색 발광 및 레이저 다이오드 구현을 이룩하였고, 열적인 안정성이 뛰어나 고온, 고출력 소자용으로도 주목받을 뿐 아니라, piezoelectric, acoustioptic modulators와 negative electron affinity devices와 같은 소자개발도 유망하다. 그러나 이렇게 다양한 응용과 물리적 특성에도 불구하고 깊은 준위의 불순물에 대한 문제는 해결되지 않은 상태이다. 많은 연구에도 불구하고 GaN에 존재하는 불순물의 성격과 그것들이 전도대에 미치는 영향에 관해서는 잘 이해되지 않고 있다. 본 연구에서는 MBE로 성장된 undoped GaN 박막의 깊은 준위에 대한 연구를 위하여 TSC 장치를 이용하여 GaN 깊은 준위를 분석하였다. TSC 실험은 77K에서 400K 사이 온도의 전류 변화를 관찰하였으며 깊은 준위의 활성화 에너지 및 포획 단면적 그리고 방출 진동수를 구하기 위하여 Initial rise method, Peak shape method, Heating rate method, Peak temperature method 등을 이용하였다. 또한 trap의 origin을 밝히기 위해서 수소화를 한후에 TSC 측정을 해보았다.

• 대한기계학회논문집B
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• 제28권7호
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• pp.857-862
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• 2004

HCCI engines take advantage of high compression ratio and heat release rate, they exhibit high efficiency in compression ignition engines. HCCI engines also utilize a lean air/fuel ratio resulting in low emissions of NOx and particulate matter(PM). The objective of this research is to determine the effects of EGR rate on the combustion processes of HCCI. For this purpose, a 4-cylinder, compression ignition engine was converted into a HCCI engine, and a heating device was installed to raise the temperature of the intake air and also to make it more consistent. In addition, a pressure sensor was inserted into each of the cylinders to investigate the differences in characteristics among the cylinders.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.37-38
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• 2016

본 논문에서는 유도가열방식 세정장치의 티타늄 용기 특성을 분석하고 전력변환장치를 설계한다. 코일에 흐를 전류를 계산하기 위한 용량 산정은 기체의 온도 변화량 및 용기 가열 시간을 고려하여 증기 가열에 필요한 열량을 수학적으로 분석하고 설계한 전력변환장치를 시뮬레이션을 통해 검증한다.

• 한국태양에너지학회 논문집
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• 제34권3호
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• pp.30-41
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• 2014

PV/Thennal combined system is a solar energy device that uses photovoltaic module as thermal absorption plate, producing thermal energy as well as electricity which can be utilized in buildings. The system removes heat from PV module through air or liquid and its efficiency will vary dependant on the thermal medium. The heat as the forms of hot air or hot water can be utilized for building use, like space heating and hot water. A significant amount of research and development on hybrid PV/thermal(PVT) collectors has been carried out. This study reviews literature on the research of air-based hybrid PVT collectors in terms of their design and energy performance.

• 한국자기공명학회논문지
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• 제23권2호
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• pp.46-50
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• 2019

Spin orbit torque would be applied as the next generation of MRAM, so many researchers are interested in related field. To make a more efficient device, electric current should convert into spin current with high efficiency. Moreover, it becomes important to measure efficiency of spin orbit torque accurately. We measured spin torque FMR of W/CoFeB hetero structure system with direct current. The efficiencies of the damping like torque and field like torque were measured by using the linewidth and on-resonance field proportional to direct current. In addition, we analyzed that a quadratic shift of the on-response field was caused by the Joule heating.

• 마이크로전자및패키징학회지
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• 제26권1호
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• pp.1-7
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• 2019

Recently, memristor (anion-based memristor) is referred to as the fourth circuit element which resistance state can be gradually changed by the electric pulse signals that have been applied to it. And the stored information in a memristor is non-volatile and also the resistance of a memristor can vary, through intermediate states, between high and low resistance states, by tuning the voltage and current. Therefore the memristor can be applied for analogue memory and/or learning device. Usually, memristive behavior is easily observed in the most transition metal oxide system, and it is explained by electrochemical migration motion of anion with electric field, electron scattering and joule heating. This paper reports the latest trends and issues of anion-based memristor.

• 대한후두음성언어의학회지
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• 제31권2호
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• pp.87-91
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• 2020

The tracheostomy directs external air into the airway tract. This process causes mucosal dryness, irritation and inflammation in the tracheo-bronchial tree. In order to prevent such problems, several methods are applied; ointment application, humidification and careful suction etc. The heat-moisture exchanger (HME) is commercially sold device that assists heating and humidification of the inhaled air. The authors experienced successful treatment outcome of intractable tracheitis caused by repetitive and vigorous intra-tracheal suction by applying HME in a total laryngectomized patient. We report an interesting and didactic case with a brief literature review.

• 셀메드
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• 제12권4호
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• pp.16.1-16.2
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• 2022

Treatment of patients with pain is directed at relieving pain and restoring function. Heat therapy has been used as a pain treatment. The mean temperatures were 40 and 41℃. Our device, Dr.Pakk heats special silicone to 41℃ with far-infrared rays and attaches it to the painful knee using a vacuum to show the effect. The core technology of the Dr.Pakk is that deep heat is generated when the heat is transmitted deeply by attaching it to the skin. In our experience, Dr.Pakk can be especially effective for knee pain.

• 토지주택연구
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• 제12권1호
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• pp.129-137
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• 2021

외부 차양장치는 대표적인 여름철 일사조절 장치이다. 특히 냉방부하가 높은 업무용 건물에 적합한 기술로 인식되어왔다. 그러나 본 연구에서는 차양장치의 냉방부하 저감뿐만 아니라 난방부하 저감 효과를 검증하기 위한 실험을 수행하였다. 이를 위해 겨울철 야간 천공복사냉각에 따른 영향을 중심으로 일반 창호, 롤 블라인드, 외부 차양장치를 대상으로 실험을 수행하였으며, 그 결과는 다음과 같다. 외부 차양장치가 적용된 경우 유리 내·외표면 온도차는 평균 11.8℃로 차양장치가 없는 경우의 14.6℃ 보다 평균 2.8℃ 낮은 온도차를 나타냈으며, 이는 천공복사에 의한 열교환으로 차양 표면온도가 외기온도보다 낮은 시간때에 발생한다. 한편, 롤 블라인드는 내부 중공층의 평균온도보다 0.8℃ 낮은 온도를 나타냈으며 이 또한 투과체를 통과한 천공복사가 롤 블라인드 표면과 열교환이 이뤄졌기 때문이다. 유리 외부 표면온도만을 고려하면 약 3℃ 이상의 온도 상승이 예상된다. 그리고 차양장치가 없는 경우 일반적인 온도구배를 나타내고 있었다. 한편 남동향과 남서향에 외부 차양장치가 설치되었을 때 남서향의 외측 유리 표면온도가 더 낮게 나타나는 특징이 있다. 이 결과는 천공복사에 의한 냉방 저감 효과를 정량화할 수는 없지만 적어도 타당성은 확인할 수 있었다. 향후 연구에서는 천공복사 냉각과 에너지 소비 사이의 상관관계를 조사하고 외부 차양장치의 난방에너지 절감 효과에 대한 독립 챔버 실험을 진행할 계획이다.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.492-498
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• 2012

A hyper branched 10-butylphenothiazine with in-situ thermally curable methacrylate (1,3,5-tris-[$\{$10-Butyl-3-(4-(2-methyl-acryloyloxy)-phenyl)-7-yl-10H-phenothiazine$\}$]-benzene, (tris-PTMA)) was synthesized successfully. From the TGA thermogram of tris-PTMA was thermally stable up to $336^{\circ}C$. In the first heating scan of DSC thermogram, tris-PTMA showed glass transition temperature (Tg) at $140^{\circ}C$ and broad endothermic process in the region of $144-179^{\circ}C$, which is thermally curing temperature. In the second heating process, $T_g$ exhibited at $158.7^{\circ}C$ and endothermic process was not observed. Thermally cured tris-PTMA showed no big change in the UV-visible spectrum after washing with organic solvent such as methylene chloride, chloroform, toluene, indicating that thermally cured film was very good solvent resistance. Thermally cured tris-PTMA was electrochemically stable and the HOMO energy level of tris-PTMA was -5.54 eV. The maximum luminance efficiency of double layer structured polymer light-emitting diode based on in-situ thermally cured tris-PTMA was 0.685 cd/A at 16.0 V, which was higher than that of the device without thermally cured tris-PTMA (0.348 cd/A at 15.0 V).