• 한국기계가공학회지
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• 제16권6호
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• pp.87-94
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• 2017

Hot stamping processes are possible for tensile strength 1.4 GPa but the strength reduction is appeared from the cooling performance unbalance. And the strength of roll forming process is below than that of hot stamping process owing to using the steel which is lower strength of boron steel. In this study, We provide roll forming process asssisted high-frequency induction heating to solve the problem of conventional one. The experiments were carried out at under various sill side part conditions: high-frequency induction heating conditions of 15, 18, 21, 24, 27 and 30 kW. The high-frequency induction heating temperature was checked with Infrared camera and the sill side parts of mechanical properties and microstructure were measured. The heating temperature of high frequency induction was measured to max $850^{\circ}C$ under the coil power of 30 kW. The tensile strength was 1.5 GPa and hardness was 490 Hv. The martensite structure was discovered under coil power of 30 kW. The weight of steel material sill side having thickness 1.5 mm and the boron steel sill side having thickness 1.2 mm were compared to weight effect. The boron steel sill side reduced 11.5% compared to steel. Consequently, manufacturing process of 1.5 giga-grade's sill side part was successfully realized by the roll forming assisted high-frequency induction heating methods.

• 대한공간정보학회지
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• 제21권1호
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• pp.27-37
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• 2013

원격 열화상으로 관측된 지붕표면 온도 분포 자료를 활용하여 쿨루프(Cool Roof)에 기인한 겨울철 난방부하에 대한 근거 자료를 확보하는 것이 본 연구의 목적이다. 원격 열화상은 지붕색상(흰색, 검은색, 청색, 녹색)에 따른 지붕표면 온도의 광역 분포패턴을 가시적으로 제시하였는데, 이는 사람의 눈으로 볼 수 있는 범위에 국한된 데이터만을 제시하는 현지조사와는 확연히 다른 특성을 보여주었다. 겨울철에 높은 태양 반사율을 갖는 쿨루프의 표면 온도는 일반 지붕에 비해 $3^{\circ}C{\sim}9^{\circ}C$ 정도 낮은 것으로 확인되었다. 쿨루프가 여름철에 일반지붕과 비교해서 $18.4^{\circ}C$ 정도 낮은 표면온도를 보여주었기 때문에 겨울철에 쿨루프로 인해 감소된 온도가 여름철에 비해 현격하게 낮아 쿨루프가 한국의 기후조건에서 상당한 잠재력이 있다는 것이 확인되었다. 본 연구는 원격 열화상을 이용하여 광역 열분포를 정량적으로 제시하였기 때문에 쿨루프로 인한 겨울철 난방 부하를 객관적으로 검증하는 과정에서 중요한 참고 자료로 사용될 수 있을 것이다.

• 대한약침학회지
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• 제6권2호
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• pp.127-135
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• 2003

The purpose of this study is to evaluate the clinical effect of Hwangryunhaedok-tang Herbal-Acupuncture. Hwangryunhaedok-tang is used in all heating diseases. Chest Heating Sensation is a unique concept in Oriental Medicine. So we applied Hwangryunhaedok-tang Herbal-Acupuncture to treat the Chest Heating Sensation. We used DITI(Digital Infrared Thermographic Imaging) to estimate the temperatures of chest surface for the outcome assessment. We came to know that the chest surface temperatures were all reduced in both cases after Herbal-Acupuncture treatment. The reduced average temperature was $1.5^{\circ}C$ in case 1 and $0.9^{\circ}C$ in case 2. The above result indicates that Hwungryunhaedok-tang Herbal-Acupuncture treatment has an effect on Chest Heating Sensation, thus continuous Hwangryunhaedok-tang Herbal-Acupuncture study will be needed for more clinical applications.

• 세라미스트
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• 제10권3호
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• pp.48-54
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• 2007

Glass-ceramics transparent above $10\;{\mu}m$ in the infrared, have been synthesized. They are based on germanium and antimony sulphides or selenides associated to alkali halides. They are prepared by heating glass samples at temperatures above the glass transition, as a function of time. Ceramisation can be controlled, so that sub-100 nm crystals are generated in the glass matrix. Then, low light scattering is achieved and the transparency window of the original glass is maintained. When gallium sulphide is added, glass ceramics can be doped with rare-earth ions. Emissions from the $^4F_{3/2}$ and $^4I_{13/2}$ of $Nd^{3+}$ and $Er^{3+}$ ions, respectively, are more intense in glass-ceramics, as compared to their vitreous counterpart. Examination of band profiles and decaytimes show that rare-earth ions are embedded in both crystalline and glassy environments.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.230-236
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• 1998

Thermal environment of greenhouse was investigated by thermo-tracer in this study. The Thermo-tracer is a high-sensitivity infrared thermometer of non-contact type. The infrared energy emitted from the measured object is converted into an electrical signal by the detector(HgCdTe) and display as a color or black & white thermal image by way of optical scanning, The experiment was conducted for Venlo-type greenhouse with pad & fan system. The temperature difference between measured by Thermo-trace and measured by HOBO sensor is maximum 0.8$^{\circ}C$. Thermo-trace is possible to use for the thermal environment analysis and diagnosis of a cooling and heating system of greenhouse.

• 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.

• 대한기계학회논문집B
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• 제41권3호
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• pp.199-204
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• 2017

열전소자를 이용하여 고온의 표면을 능동적으로 냉각하여 적외선 방사량을 줄이는 기술을 소개한다. 공력가열이나 자체 발열 등에 의한 고온 표면 환경을 구현하였고, 여기에 열전소자를 설치하여 냉각하였을 때의 표면 온도와 적외선 방사량을 상용 수치해석 소프트웨어를 사용하여 계산하였다. 이를 통해 특정 환경에서 열전냉각소자를 이용하여 고온 표면에 있어 외부 환경과 비교했을 때의 적외선 방사량 대비를 이론적으로 완전히 제거할 수 있음을 확인하였다.

• 동력기계공학회지
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• 제21권3호
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• pp.30-36
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• 2017

Carbon fiber shows excellent heat generation value and thermal efficiency comparing with the metallic materials because of its far infrared-rays and radiant heat. So, high performance and economic steam boiler system for the industry can be manufactured by using the carbon fiber heater. The far infrared ray radiation rate was more than 90 % of carbon fiber. Steam boiler system with carbon fiber heater in this study is made up of heating section. In the proof test of steam boiler, the aimed temperature and dwelling time were at $500^{\circ}C$ for 8,000 hours, $600^{\circ}C$-3,000 hours, and $700^{\circ}C$-1,000 hours. The temperature rise rate of steam boiler with carbon fiber heater was about 40% faster than that of the conventional boiler.

• 한국군사과학기술학회지
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• 제17권1호
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• pp.82-89
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• 2014

The damage in germanium (Ge) optical window irradiated by a near-infrared continuous wave (CW) laser was studied. Laser-induced heating and melting process were surveyed, and the specific laser power and the irradiance time to melt were estimated by numerical simulation. The experiments were also carried out to investigate the macro and micro structure change on Ge window. Results showed that the surface deformation was formed by melting and resolidification process, the damaged surface had a polycrystalline phase, and the transmittance as an optical performance factor in mid-infrared region was decreased. We confirmed that an abnormal polycrystalline phase and surface deformation effect such as hillock formation and roughness increase reduced the transmittance of Ge window and were the damage mechanism of CW laser induced damage on Ge window.

• 비파괴검사학회지
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• 제37권2호
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• pp.91-98
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• 2017

Recently, composite materials have been mainly used in the main wings, ailerons, and fuselages of aircraft and rotor blades of helicopters. Composite materials used in rapid moving structures are subject to impact by hail, lightning, and bird strike. Such an impact can destroy fiber tissues in the composite materials as well as deform the composite materials, resulting in various problems such as weakened rigidity of the composite structure and penetration of water into tiny cracks. In this study, experiments were conducted using a 2 kW halogen lamp which is most frequently used as a light source, a 2 kW near-infrared lamp, which is used for heating to a high temperature, and a 6 kW xenon flash lamp which emits a large amount of energy for a moment. CFRP composite sandwich panels using Nomex honeycomb core were used as the specimens. Experiments were carried out under impact damages of 1, 4 and 8 J. It was found that the detection of defects was fast when the xenon flash lamp was used. The detection of damaged regions was excellent when the halogen lamp was used. Furthermore, the near-infrared lamp is an effective technology for showing the surface of a test object.