• Journal of the Optical Society of Korea
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• 제12권3호
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• pp.200-204
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• 2008

Coherent tunable terahertz generation was demonstrated in periodically poled stoichiometric lithium tantalate crystal via difference frequency generation of femtosecond laser pulses. Simultaneous forward and backward terahertz radiations were obtained around 1.35 and 0.63 THz, respectively at low temperature. By cooling the crystal to reduce losses caused by phonon absorptions, the generated THz bandwidth was as narrow as 23GHz at the center frequency of 0.63 THz. The measurement result of temperature-dependent showed gradual intensity increase of the generated terahertz pulse and red shift of the center frequency as the temperature decrease from 291 to 143 K, but insignificant reduction of the spectral bandwidth. Furthermore, the stoichiometric crystal was very suitable for the suppression of THz loss at low temperature compared to the congruent $LiNbO_3$ crystal.

• 수산해양기술연구
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• 제51권1호
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• pp.94-101
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• 2015

The heat treatment machine based on immersion was developed to reduce temperature difference during netting process and appraised it performance compared current heat treatment machine using high pressure. It was also reviewed the optimum heat treatment procedures for PBSAT monofilament net in accordance with the immersion time and temperature. The procedure was based on physical measurement such as breaking load, elongation and angle of the mesh for PBSAT monofilament. The water temperature gap of the treatment machine based on immersion was less than $1^{\circ}C$. and the energy consumption was also increased in high temperature condition. It was identified that the optimum temperature was $75^{\circ}C$ and its optimum processing time was between 15 minutes and 20 minutes to get qualified physical properties.

• 중환자간호학회지
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• 제10권3호
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• pp.53-64
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• 2017

Purpose : This study investigated the effects of active warming using a Warm Touch warming system or a cotton blanket in postoperative patients after general anesthesia for abdominal surgery. Methods : This quasi-experimental study utilized two experimental groups and one control group: a cotton-blanket group (n = 25) were warmed with a cotton blanket and a sheet; a forced-air warming group (n = 24) were warmed with a Warm Touch warming system, a cotton blanket, and a sheet; and a control group (n = 25) were warmed with a sheet. Measurement variables were postoperative pain, body temperature, and thermal discomfort. Data were analyzed using a one-way ANOVA, ${\chi}^2-tests$, Fisher's exact test, and a repeated measures ANOVA. Results : The effects of active warming using a Warm Touch warming system and a cotton blanket on postoperative patients was significant in reducing pain (F = 13.91, p < .001) and increasing body temperature (F = 12.49, p < .001). Conclusion : Active warming made a significant difference in pain and body temperature changes. Active warming methods may help patients' postoperative recovery and prevent complications. Further research is needed to explore the effects and side effects of active warming on recovering normothermia.

• 한국의류산업학회지
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• 제10권5호
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• pp.668-675
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• 2008

The purpose of this study was to collect data of skin temperature and physiological responses which is useful for standardization of insulation measurement in various garments. And we investigated sex and season difference of physiological responses of 60's males and 60's females in hot and cold environment. Healthy ten 60's males and ten 60's females volunteered as subjects. The experiment was conducted three times; One for winter condition($5^{\circ}C$, 45%), another for summer condition($30^{\circ}C$, 65%) and the other for nude condition as control($30^{\circ}C$, 65%). The subjects were sitting for 1 hour with suitable ensemble on each experimental condition in climate chamber. We measured skin temperature, rectal temperature, heart rate, oxygen uptake, sweat rate, blood flow, blood pressure and subjective sensations. We found that skin temperature and most of physiological responses were higher in male subject, summer condition than in female subject, winter condition.

• Journal of the Korean Wood Science and Technology
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• 제22권4호
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• pp.37-42
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• 1994

The adsorption of water vapor and equilibrium moisture content(EMC) of the specimens for four softwood species dried by conventional- and high temperature method and equilibrated to 15% of the target EMC condition at 25$^{\circ}C$ were determined by oven drying method and with moisture meters. The amount of adsorption for high temperature dried red pine was significantly higher than that of conventional kiln dried wood, while those of eastern white pine, eastern hemlock and Norway spruce were not significantly different between drying methods. EMCs of these four species determined by oven drying method and with capacitive admittance moisture meter were not significantly different between drying methods. EMC of high temperature dried red pine determined with resistance moisture meter was significantly higher than that of conventional kiln dried wood. But EMCs of other species did not show significant difference between drying methods. EMCs of conventional and high-temperature dried wood determined with electronic moisture meters, especially in the case of the capacitive-admittance moisture meter measurement, were lower than that determined by oven drying method.

• 대한한방부인과학회지
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• 제28권4호
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• pp.11-20
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• 2015

Objectives The purpose of this study was to examine the relationship between cold hypersensitivity and bone mineral density. Methods 28 outpatients who visited OO University Oriental Hospital from July 11th, 2013 to August 28th, 2013 were analyzed. Patients were subjected to thermometer, and those with thermal difference greater than 0.3 ℃ between upper arm and palm and also with more than VAS 4 of cold hypersensitivity were diagnosed with cold sensitivity. Lumba spine (L2-4) and heel bone measurement were obtained on dual energy X-ray absorptiometry (DEXA) and Quantitative Computed Tomography (QCT). Results 1. There was statistically significant correlation between T-score of DEXA and body weight (0.522), BMI (0.643), OSTA (Osteoporosis elf-assesment Tool for Asians, 0.579), BMI, T-score and Z-score of QCT. OSTA and T-score of QCT (0.521) also had statistically significance. 2. There was no statistically significant correlation between body fat, abdominal obesity rate, degree of cold hypersensitivity, upper arm and palm's temperature difference, palm temperature, height and Z-score, T-score of QCT or T-sore of DEXA. Conclusions Bone mineral density was lower in women who had cold hypersensitivity of hand and feet. But there was no statistically significant correlation between bone mineral density and degree of cold hypersensitivity, upper arm and palm’s temperature difference.

• 한국지리정보학회지
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• 제17권2호
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• pp.156-172
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• 2014

본 연구는 미기후 분석 프로그램인 ENVI-met 모델의 정확도를 검증하기 위해 경상남도 창원시를 대상으로 도시지역의 주요 토지이용 유형별 공간특성을 고려하여 선정된 조사구역의 현장측정 기상자료와 비교하였다. 현장측정은 주간시간대 2일, 야간시간대 1일 총 3일간이동식으로 측정하였고, ENVI-met 모델링은 현장측정과 동일한 시간대로 설정하여 수행하였다. 측정항목별 분석결과에 따르면, 주간시간대의 순복사에너지는 ENVI-met 모델링이 현장측정값보다 약 $300Wm^{-2}$ 정도 높았고, 야간시간대는 현장측정값이 $200Wm^{-2}$ 정도 더 높았다. 기온은 주간 및 야간 시간대 모두 현장 측정값이 약 $3{\sim}6^{\circ}C$ 정도 더 높은 것으로 분석되었다. 표면온도도 현장측정값이 ENVI-met 모델링보다 약 $7{\sim}13^{\circ}C$ 더 높았다. 풍속은 ENVI-met 모델링과 현장측정값 간의 차이가 매우 큰 것으로 나타났다. 회귀분석 결과에서는 기온자료의 $R^2$값이 약 0.6정도로 비교적 높게 나타난 반면에, 나머지 순복사에너지와 표면온도, 풍속은 낮은 상관성을 보였다. 이는 ENVI-met 모델링이 태양 및 지구복사에너지를 과대 또는 과소 예측하고 있으며, 모델링 및 현장측정을 위해 선정된 조사구역들을 둘러싸고 있는 인접한 주변 지역의 공간구조적, 미기후적 특성 차이에 의한 영향으로 판단된다. 따라서 향후 이에 대한 보다 면밀한 실증적 연구가 필요할 것으로 판단된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.27-30
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• 2002

In this paper, we were investigated leakage current properties of outdoor insulator on climatic environmental factor. Contamination is one of the most important factor to determine the performance of insulator. Thus, it is very important to exam the contamination degree on the outdoor insulator. There are many limits, such as reliability of data, interval of measurement and similarity of environmental conditions, in conventional method. So, we measured phase and leakage current of outdoor insulator using the temperature & humidity chamber. In this investigation, phase difference was measured to compare the variance of phase difference with the contamination degree and relative humidity.

• 생물환경조절학회지
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• 제18권3호
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• pp.215-224
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• 2009

공기유동 제어기술의 개발을 위한 기초자료를 제공 할 목적으로 토마토 재배 온실의 냉난방과 환기 및 공기유동 관련 실태를 조사하고, 온실유형과 난방방식별 온습도 분포를 실측하여 균일도를 분석하였다. 충남 부여 세도지역의 토마토 재배 온실 136농가를 대상으로 조사한 결과 대부분을 차지하는 단동 플라스틱 온실의 천창 설치 비율이 낮고 환기팬과 유동팬 설치비율도 매우 낮을 뿐만 아니라 설치제원도 편차가 매우 큰 것으로 나타났다. 아치형 단동 플라스틱온실의 천창 환기 구조의 개발보급과 연동곡부의 천창도 지붕상부로 이동시킬 필요가 있으며, 개별 천창구조 및 환기팬과 유동팬에 대한 설치 가이드라인의 제정이 요구된다. 냉방설비를 설치한 농가는 하나도 없었으며 난방방식의 대부분을 차지하는 온풍난방에서 덕트의 설치제원 역시 편차가 큰 것으로 나타났고, 온풍덕트의 배기풍속 및 배기온도 또한 거리에 따른 편차가 매우 큰 것으로 관측되었다. 수출경쟁력 화보를 위한 고품질의 생산물을 연중 안정적으로 생산하기 위해서는 온실냉방기술의 보급이 절실하며 난방방식이나 덕트설치 방식의 개선이 필요한 것으로 판단된다. 온실내 온습도 분포가 균일한지 여부를 판단하는 지표로 사용되고 있는 최대 편차와 실제 균등한 정도를 나타낼 수 있는 균일도와의 관계를 분석해 본 결과 높은 상관관계를 보였으나 주간에는 직선식으로 야간에는 2차 곡선식으로 다르게 표현되었다. 온습도 분포의 균일한 정도를 판정할 수 있는 객관적인 기준이 마련된다면 최대편차 대신 균일도를 지표로 사용하는 것이 더 합리적일 것으로 판단된다. 온실유형과 난방방식에 따라 온 습도분포의 균일도가 상당히 다른 것을 확인할 수 있었으며 야간에는 온수난방의 경우 이랑배관으로, 온풍난방의 경우 온풍덕트의 적절한 배치를 통하여, 주간에는 환기와 공기유동을 통하여 균일도를 개선할 수 있을 것으로 판단되었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1058-1062
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• 2004

High-temperature cylindrical stainless steel/sodium heat pipe was manufactured and tested under long-term operation. The container material was stainless steel 316L and the working fluid was sodium. The heat pipe was 25.4 mm in diameter and 1000 mm in length with a two-layer screen mesh wick. The evaporator part was 600 mm and the condenser part was 300 mm in length. Total measurement points on heat pipe were 15 points and 12 points were located in condenser part. The heat pipe was heated for 142 days(3400 hours) at $800^{\circ}C$. In the test period, the maximum temperature difference was increased from $18^{\circ}C$ o $28^{\circ}C$ and the maximum thermal resistance was as low as $0.015^{\circ}CW$.