• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.16.1-16.1
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• 2005

• 정보학연구
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• 제9권3호
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• pp.67-75
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• 2006

This study deals with the computing the temperature change of surface to the increment of time and diffusivity, the heat flux during irradiation of laser. In addition, the computer algorithm for computing the penetration change of the corresponding surface irradiated is developed. The result of this study shows the possibility to treatment of cancer, abnormal cell and biological tissue during irradiation of laser.

• 한국보건간호학회지
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• 제18권1호
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• pp.39-49
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• 2004

The purpose of this study was to investigate the effect of moxibustion heat therapy(Koryo hand acupuncture) on menstrual cramps. dysmenorrhea and ADL. The experiment was carried out during the period from March 24 to April 30, 2003. The subjects in the study were drawn from female students attending two colleges in Chungcheongbuk-do and Kyunggi-do. Of all those subjects. 19 and 14 subjects were assigned to the experimental and the control groups respectively. The moxibustion heat therapy were performed three times a week, subjects were treated twice a time. Data was analyzed using SPSS/WIN10.0 by $x^2$test. Wilcoxon sign rank. and Wilcoxon rank sum test. The result of this study were as follows : 1) After moxibustion heat therapy. the graphic rating score of menstrual cramps was decreased significantly from 7.79(SD=1.22) to 4.47(SD=2.25) in experimental group(z=-3.731. p=.000). And there was significant difference in the change of graphic rating score of menstrual cramps between both groups(z=-3.637. p=.000). 2) After moxibustion heat therapy. the score of face rating scale of menstrual cramps was decreased significantly from 3.95(SD=0.71) to 2.32(SD=1.00) in experimental group(z=-3.457. p=.000). And there was significant difference in the change of face rating score between both groups(z=-2.713. p=.007). 3) After moxibustion heat therapy. the score of adjective labor pain rating scale rank (ALPRS) of menstrual cramps was decreased significantly from 23.63(SD=4.19) to 17.27(SD=6.34) in experimental group(z=-2.941. p=.001). But there was no significant difference in the change of adjective labor pain rating score(ALPRS) of menstrual cramps between both groups(z=-1.918. p=.059). 4) After moxibustion heat therapy. the score of dysmenorrhea was decreased significantly from 7.0(SD=2.89) to 5.26(SD=3.54) in experimental group(z=-2.183. p=.029). But there was no significant difference in the change of the score of dysmenorrhea between both groups(z =-1.555. p=.125). 5) After moxibustion heat therapy, the score of ADL difficulty was decreased significantly from 33.26(SD=4.58) to 28.83(SD=9.44) in experimental group(z=-3.552. p=.000). And there was significant difference in the change of score of difficulty of ADL between both groups(z=-4.110. p=.000). The above finding indicated that the moxibustion heat therapy showed a practical effect on reducing menstrual cramps, dysmenorrhea and ADL difficulty in female. Accordingly. we can adopt the moxibustion heat therapy as a useful intervention in the community nursing.

• 해양환경안전학회지
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• 제27권5호
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• pp.647-655
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• 2021

IMO에서는 선박으로부터 온실가스 감축을 위해 선박의 에너지효율 증진에 관한 논의를 진행하고 있다. 현재, 선박으로부터 발생되는 폐열을 이용한 ORC 발전 시스템을 적용함으로써 선박으로부터 높은 에너지 변환 효율을 기대할 수 있다. 이 기술은 물보다 더 낮은 온도 범위에서 증발하는 프레온 또는 탄화수소 계통의 유기 매체를 작동 유체로 사용한다. 이를 통해 상대적으로 낮은 저온에서 증기(기체)를 생성 및 동력을 발생시킬 수 있다. 본 연구에서는 유기 랭킨 사이클인 ORC 발전 시스템에서 냉매와 폐열 사이 열·유동해석(Analysis of Heat flow)을 3D 시뮬레이션 기법을 이용하여 구조물의 내·외부에 흐르는 유체가 온도 변화, 속도 변화, 압력 변화 및 질량 변화를 통해서 구조물에 어떤 영향을 미치는지를 분석하고자 하며, 동 연구는 이 기법을 이용하여 ORC 발전 시스템에서 냉매와 선박 주기관의 배기가스로부터 일어나는 열교환기의 열전달을 해석하였다.

• 폴리머
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• 제34권3호
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• pp.261-268
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• 2010

본 연구에서는 상전이 온도가 36 $^{\circ}C$인 n-eicosnae을 열가소성 폴리올레핀 고분자인 폴리프로필렌과 블렌드하였으며, 또한 최근의 형태안정성 PCM(SSPCM)의 연구검토를 통하여 폴리프로필렌과 n-eicosnae의 특성과 잠열저장체로서의 적용 가능성을 확인하였다. 상전이 온도가 36 $^{\circ}C$인 n-eicosane과 폴리프로필렌을 멜팅방법과 흡수방법을 이용하여 시료를 제조하였다. 제조된 형태안정성 PCM(SSPCM)을 DSC, WAXD, FTIR spectroscopy, ARES로 분석결과 형태안정성, 열용량의 향상을 확인하였다.

• 한국추진공학회지
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• 제16권1호
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• pp.64-71
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• 2012

환경조절장치는 일반적으로 냉각기계와 열교환기를 주요 구성품으로 한다. 그런데, 본 연구에서는 환경조절장치의 천이성능 향상을 위하여 상변화 열교환기를 추가하는 새로운 개념을 제시하였다. 그 효과는 상변화 열교환기를 포함하는 환경조절장치의 모델링 프로그램을 개발하여 이륙, 기동, 순항, 착육 등과 같은 다양한 비행조건에 대하여 평가되었다. 다양한 조건에서의 시뮬레이션 결과, 회수되는 공기의 온도가 $80^{\circ}C$ 이내를 유지하는 것이 확인되어, 상변화 열교환기를 포함하는 새로운 환경조절장치의 개념이 성공적으로 검증되었다.

• 열처리공학회지
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• 제4권3호
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• pp.54-62
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• 1991

The effect of tempering temperature on the ultrasonic propagation velocity at SCM 440 steel quenched from $870^{\circ}C$ and $1000^{\circ}C$ has been studied by metallurgical and crystallographical observation. The measurements of ultrasonic velocity were made on the specimen by appling an immersion ultrasonic pulse-echo technique with a constant frequency of 10 MHz. The quenched microstructure of this steel was a lath martensite. As the tempering temperature was increased, the martensite was transformed into the tempered martensite composed of cementite and carbide. The ultrasonic velocity increased with increasing the tempering temperature. It was thought that these were resulted from the microstructural transformation. The change of ultrasonic propagation velocity with quenching and tempering heat treatment was resulted from microstrain due to the change of internal stress. Considering these results concerning to the change of ultrasonic propagation velocity. the phenomena of microstructural transformation were estimated. Consequently, it was thought that the degree of quenching and tempered heat treatment of steel could be nondestructively evaluated with the change of ultrasonic propagation velocity.

• 한국가구학회지
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• 제25권4호
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• pp.319-324
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• 2014

Red pine is a popular species for making a cutting board in Korea, but easily sap stained. Heat treatment could improve its quality by darkening and equalizing the color of sap stained wood. The color change of sap stained red pine boards was investigated by heat treatment at $190^{\circ}C$. It was observed that the color of heat treated boards got darker and it made the color of sap stain vanished. A colorimeter was used to measure color indexes. It was revealed that the values of the lightness ($L^*$) and the yellowness ($b^*$) decreased as heat treatment repeated while the values of the redness ($a^*$) increased. The average of the color difference (${\Delta}E^*$) between the control and 1st heat treated boards was 16.1, which could be expressed as 'Extremely different' while that between the 1st and 2nd heat treated boards was 8.3, which could be expressed as 'Considerably different'. The fact that heat treatment equalized the color of boards was confirmed by a statistical analysis.

• KIEAE Journal
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• 제14권6호
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• pp.81-86
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• 2014

In recent years, many researchers have considered the building energy consumption reduction accordingly to deal with abnormal climate changes and greenhouse gas reduction. However, the lighting energy use ratio has increased in spite of the development of the high efficiency lighting device. Therefore, the study aims to produce the LED lighting applications for the effective lighting heat removal by using the heat characteristics of LED lighting and analyzing the heat removal effect. In order to increase radiant heat efficiency, the heat pipe and heat sink was attached on PCB as LED lighting applications. Experiment was conducted to verify the temperature and air velocity of inside duct: thermocouples, anemometer. The heat removal effect of LED lighting applications was measured by observing the temperature of the lighting applications and the change of air velocity in duct. The experiment shows that the temperature change in the duct according to air velocity was $0.9{\sim}5.8^{\circ}C$. It is also concluded that heat removal was calculated from 33 to 81W.

• 한국태양에너지학회 논문집
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• 제24권1호
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• pp.7-12
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• 2004

Mixtures type PCM, $H_2O$-NaOH that has relatively large capacity of the latent heat and long duration of phase change temperature was developed and experimentally analyzed for the low temperature storage of the food and medical products. The results could be summarized as follows; 1. Borax as nucleating agent and acrylic polymer as thickening agent were added to $H_2O$ to prevent the supercooling and phase separation. 2. Phase change (solid$\leftrightarrows$liquid) duration of $H_2O$ added with NaOH was prolonged longer 50% than that of pure $H_2O$. 3. Phase change temperature of the latent heat material, $H_2O$-NaOH was $1.5\sim2^{\circ}C$ the maximum latent Heat was 279 kJ/kg at the NaOH addition of 1.3 wt.%. 4. The specific heat of $H_2O$-NaOH at the solid and liquid state was increased in proportion to the wt.% of NaOH, when NaOH of $1.15\sim1.60$ wt.% was added to $H_2O$, the specific heat of the solid state was increased from 3.19 kJ/kg to 5.84 kJ/kg and that of liquid state from 7.8 kJ/kg to 10.28 kJ/kg. 5. When NaOH of $1.15\sim1.60$ wt.% was added to $H_2O$, the total heat storage capacity composed of sensible and latent heat was $313\sim331.3$ kJ/kg and the maximum heat storage capacity was occurred at NaOH addition of 1.30 wt. %.