• 한국신뢰성학회지:신뢰성응용연구
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• 제5권4호
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• pp.487-500
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• 2005

MEMS devices usually have micro actuators contained in a cavity, If the pressure level of testing chamber is higher than that of cavity, moisture will ingress into the cavity, which may cause critical failure such as stiction of the moving parts. To design an accelerated life test based on high temperature and high humidity, such a phenomena should be considered. In this study, a throughput model that can estimate the amount of moisture ingress is used to decide the testing time and conditions of a high temperature and high humidify test.

• Ecology and Resilient Infrastructure
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• 제4권4호
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• pp.187-192
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• 2017

본 연구는 보도, 차도, 주차장, 공원, 광장 등에서 많이 사용되고 있는 포장 재료인 블록의 증발 등 열적 성능을 평가하였다. 일반적으로 많이 사용되고 있는 일반블록과 LID (Low Impact Development)형 제품인 투수블록과 보수블록을 비교하였으며, 통제된 기후조건 (일사, 강우, 강설, 온도, 습도 등)이 갖춰진 챔버 (chamber) 내에서 실험을 수행하였다. 환경챔버 내의 공기온도와 상대습도가 제어되는 상태에서 강우설비와 로드셀을 활용하여 강우전과 후의 중량변화 및 일사장치와 송풍장치를 이용하여 증발량을 계측하였다. 결과적으로 보수블록이 일반블록에 비해 증발산량은 약 2.6배 많았으며, 표면온도는 $10^{\circ}C$, 공기온도는 $4.6^{\circ}C$ 낮았다. 따라서 블록시험에 강도, 투수성능뿐만이 아닌 열에 대한 부문도 추가하여 분석한다면, 도시의 열 환경개선에도 많은 도움이 될 수 있을 것이다.

• 한국건축시공학회지
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• 제7권1호
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• pp.91-98
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• 2007

In this study, the property and plastic cracking pattern of concrete were compared and analyzed with the replacement ratio of fly ash 0, 5, 10, 15, 20% by cement weight. And curing conditions of concrete were given variously such as indoors(with wind speed as 0, 300, 500m/min), outdoors and chamber. The hydration temperature had a tendency to decrease as the replacement ratio of fly ash increased, and in the case of the wind speed 0m/min, it was showed that the moment that the amount of evaporation of water from surface of reference concrete was more than the volume of bleeding was 90 min since casting concrete. The time that the crack initiated had a tendency to be more quickly as the replacement ratio of fly ash increased. The number, length, width and area of crack in the indoor curing, exposed outdoor curing, enclosed outdoor curing had a tendency to decrease as the replacement ratio of fly ash increased. The crack had a tendency to decrease in sequence of exposed outdoor, enclosed outdoor curing, indoors curing. The outbreak of cracking by the change of temperature and humidity was affected by relative humidity more than temperature and the cracking had a tendency to increase as relative humidity lowered.

• 보존과학회지
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• 제27권2호
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• pp.231-241
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• 2011

박물관에서 질소나 아르곤과 같은 불활성 가스를 사용한 저산소 농도 살충처리법은 메틸브로마이드나 유독성 살충제의 대체법으로써 성공적으로 사용되어 왔다. 저산소 농도 살충법의 살충 효과는 해충의 종, 산소 농도, 온도, 습도, 가스의 종류 등에 따라 영향을 받으며, 박물관에서의 문화재 보존 환경(온도 $15{\sim}25^{\circ}C$, 습도 40~60%)에서 산소 농도를 0.03% 이하로 유지함으로써 1개월 이내에 가장 내성이 강한 문화재 해충의 살충이 가능하다. 그리고 살충 처리 대상 문화재의 수량이나 크기에 따라 소형 중형 백, 대형 텐트, 버블, 챔버 등 다양한 시스템을 적용할 수 있다.

• 복식문화연구
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• 제13권3호
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• pp.406-413
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• 2005

This study performed the evaluation of skin temperature, heart rate, temperature and relative humidity of microclimate, and subjective sensation, such as thermal sensation, wet sensation and comfort sensation to estimate physiological responses of the human body and its comfortable feeling to the vitamin E fabric. Experiments were performed on the five healthy adult women whose average age was 21, at climate chamber in which temperature, relative humidity and air current were set up below $30{\pm}\;1^{\circ}C$, $50{\pm}\;15\%$ and 0.2m/s, respectively. Two kinds of clothes were used for experiments: unfinished sports clothes, with the same form and the same size, of short-sleeved knit shirt and long trousers made with $100\%$ cotton, and finished sports clothes printed with the vitamin E solution of the level of $0.88\%$. Exercises of walking (about 105 steps/minute) with the exercise intensity of 2.5 were performed for 20 minutes using treadmill. In result, the study showed significant difference (p<0.01) in average skin temperature between unfinished and finished sport clothes, and represented higher value with having unfinished sport clothes in wear than with finished one. The study also showed significant difference (p<0.01) in heart rate only during the period of exercise, and represented higher value generally with unfinished sport clothes than with finished one. There were significant differences not only in temperature of microclimate (p<0.01) but also in humidity of microclimate (p<0.05) between two sport clothes. As for the evaluation of subjective sensation, the study showed significant difference (p<0.05) in thermal sensation between the two kinds of sport clothes, significant difference in wet sensation only during the period of exercise, and significant difference (p<0.05) in comfort sensation only during the period of recovery.

• 화훼연구
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• 제16권1호
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• pp.1-6
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• 2008

본 실험에서는 Ardisia속 자생식물의 온도 및 습도변화에 따른 온열환경을 조사함으로써 자생식물의 이용에 가능한 기초 자료를 제공하고자 실시하였다. 가로 2m, 세로 1.3m, 높이 1.8m, 총 부피가 $4.68m^3$의 밀폐된 유리 챔버 내에 온도 조건 변화에 따른 실내공간의 온도 및 습도변화를 측정한 결과, Ardisia속 식물에 의한 실내온도의 변화는 $24^{\circ}C$ 이상의 고온에서는 식물이 없는 상태에 비해 감온 효과가 있었으며 3종의 식물 간 큰 차이는 보이지 않았다. Ardisia속 식물 중에서 백량금이 온도 변화에 따른 습도 변화가 가장 민감하게 일어나 13%의 습도 변화를 보였고 $57.3{\pm}3.1%$로 비교적 높은 습도를 보였는데, 이에 비해 자금우는 8%, 산호수는 9%의 습도 변화를 보였고 자금우와 산호수 모두 대부분의 낮 시간 동안 50~55%의 실내 적정습도 범위를 유지했다. 식물체의 실내 발열체로서의 열성능 평가 결과, 실내 온도를 $28^{\circ}C$에서 $26^{\circ}C$로 감온 시에는 식재에 의한 냉방 효과가 비식재 공간에 비해 7.5~13.6배 높았고, 적정온도 이상의 고온에서는 자금우에 의한 냉방 효과가 백량금과 산호수에 비해 더 좋았으며 적정온도를 유지하는데 효과적이었다. 실내 저온 조건에서는 비식재 공간이 식물을 배치한 경우보다 높은 열량을 나타내 식물이 저온 조건에서 냉방효율을 낮추므로 적정온도를 유지하는데 효과적이었다. 이로서 Ardisia속 식물은 고온의 실내에서 주위의 온도를 저하시키고 적정온도를 유지시키는데 효과적임을 알 수 있었다.

• 한국의류학회지
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• 제28권6호
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• pp.767-775
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• 2004

In order to evaluate physiological responses and comfort sensation of the developed thermoregulating textile material, polyester knit fabric was treated with phase change material (PCM) microcapsules by printing. Ten male subjects wearing an experimental best with and without PCMs were seated for 20 minutes, then exercised for 20 minutes, and then seated for 30 minutes in the chamber which was controlled under the temperatures of 20$\pm$1$^{\circ}C$, 50$\pm$5%R.H. The subject's skin temperature, microclimate inside garment and comfort sensation of two experimental bests were compared one another. As a result, the rectal temperature, skin temperature and mean skin temperature were similar in the two groups, and the subjects were not able to perceive the differences in comfort of the two experimental bests. However, the effect of PCM microcapsule could be seen from microclimate temperature and humidity. The microclimate temperature of the PCM garment at chest was significantly higher during exercise. The microclimate humidity of the PCM garment at chest was significantly lower during exercise and rest.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.159-164
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• 2000

In this study, the deformation analysis of 80mm optical disk holder considering the creep characteristics of plastic materials has been conducted and experimentally verified. It is very important to remedy the unrecoverable creep deformation and relaxation of holding force of an optical disk holder for the reliability of DVDR-P, DVD-ROM. A disk holder inserted in a cartridge case has been kept in the chamber with $60^{\circ}C$ temperature and 90% humidity for 24 hours. After storage test, the arm span and holding force of a disk holder have been measured after 24 hours at room temperature and normal humidity. The predicted results are in good agreement with experimentally measured one.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1327-1334
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• 2011

subway has became citizen's feet which can transport over 24 million people since the era of high oil price started. Because the request of passengers for more comfortable thermal comfort is drastically increasing, the importance of comfortable environment in the passenger car is more stressed. This paper suggests an indicator whether railroad car is fitted with suitable cooling and heating equipment by applying the international climatic testing method, UIC 553, 553-1. Specified ambient temperature, humidity, solar irradiation condition, as well as extreme outside condition, can be achieved by using an environmental chamber. The change temperature and humidity in the passenger space can be monitored to judge if the passenger room is nicely air-conditioned.

• 한국항행학회논문지
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• 제27권1호
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• pp.71-76
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• 2023

본 논문에서는 마이크로스트립 패치 안테나와 폴리비닐알코올(PVA; polyvinyl alcohol)을 이용한 습도 센서에 대하여 연구하였다. PVA는 습도에 따라 유전율이 변하는 고분자 물질이며, 전계 변화에 민감한 마이크로스트립 패치 안테나의 방사면에 직사각형 슬롯을 추가하여 비유전율 변화에 대한 감도를 높였다. 0.76 mm 두께의 RF-35 기판에 제작된 안테나의 직사각형 슬롯이 추가된 방사면 주변을 PVA로 얇게 코팅한 후, 온습도 챔버를 사용하여 25도에서 상대습도를 40%에서 80%까지 10% 간격으로 증가시켜 안테나 입력 반사 계수의 공진 주파수와 크기의 변화를 측정하였다. 실험 결과, 상대습도가 40%에서 80%로 증가할 때 안테나 입력 반사 계수의 공진 주파수는 2.447 GHz에서 2.418 GHz로 감소하였고, 입력 반사 계수의 크기는 -7.112 dB에서 -3.428 dB로 증가하였다.