• 대한기계학회논문집B
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• 제23권5호
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• pp.653-660
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• 1999

This work describes analysis on the effect of inlet air cooling by the cold energy of liquefied natural gas(LNG) on the performance of gas turbines. Gas turbine off-design analysis program to simulate the influence of compressor inlet temperature variation is prepared and an inlet air cooler is modeled. It is shown that the degree of power augmentation is much affected by the humidity of inlet air. If the humidity is low enough, that is the water content of the air does not condense, the temperature drop amounts to $18^{\circ}C$, which corresponds to more than 12% power increase, in case of a $1350^{\circ}C$ class gas turbine with methane as the fuel. Even with 60% humidity, about 8% power increase is possible. It is found that even though the fuel contains as much as 20% ethane in addition to methane, the power improvement does not change considerably. It is observed that if the humidity is not too high, the current system is feasible oven with conceivable air pressure loss at the inlet air cooler.

• 한국대기환경학회지
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• 제19권2호
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• pp.167-177
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• 2003

The number size distribution of urban aerosols ranging from 0.02 to 20 ${\mu}{\textrm}{m}$ in diameter was measured by using a scanning mobility particle sizer (SMPS) system and an aerodynamic particle sizer spectrometer (APS) at Seoul from November 30,2001 to January 14, 2002. The gaseous species such as CO, NO, NO$_2$, and $O_3$ were also continuously monitored. The daily average concentration of urban aerosols sorted into three groups (0.02~0.1 ${\mu}{\textrm}{m}$, 0.1~1 ${\mu}{\textrm}{m}$ and 1~10 ${\mu}{\textrm}{m}$) and the typical number, surface, and volume distributions of urban aerosols were discussed in this paper. The weekly variation of aerosol concentration was compared with those of gaseous concentrations. relative humidity, and visibility. The results showed that the particle number concentration seemed to increase in the morning and the number concentration of fine particles less than 1 fm in diameter seemed to increase when the concentrations of CO, NO, and NO$_2$ were high. The number concentration of fine particles was relatively high when the relative humidity was greater than 70％ during the increasing period of relative humidity. The visibility was weakly correlated with the concentration of aerosols ranging 0.1 to 1 ${\mu}{\textrm}{m}$, and the number size distribution for high visibility episode was apparently different from that for low visibility episode.

• 설비공학논문집
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• 제26권11호
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• pp.504-511
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• 2014

The objective of this study is to theoretically analyze the performance of an open wet air-cycle refrigeration system, which nowadays is increasingly generating environmental concern. The temperature and relative humidity of the outside air are selected as the most important parameters. As the temperature and relative humidity of the outside air increase, the pressure ratio of the ACM compressor is determined to be nearly constant, the air temperature at the exit of the system increases, and the amount of condensed water, the cooling capacity, the COP, and the total entropy production rate increase overall. The effects of the effectiveness of the heat exchanger and the efficiency of the turbine on the performance are greater than that of the efficiency of the ACM compressor. Also, the performance of the wet air-cycle refrigeration system with two heat exchangers is enhanced, with a high COP and low total entropy production rate, compared to the system with a single heat exchanger.

• 한국수소및신에너지학회논문집
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• 제29권3호
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• pp.292-298
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• 2018

The contamination of photovoltaic (PV) cells reduces the incidence of sunlight and reduces the power generation output of PV cells. The main factor influencing the contamination of PV cells installed outdoors is the fine dust in the air, but the influence of temperature, humidity, rain and wind can be considered. In this paper, experiments on the contamination of PV cells according to the fine dust density, the temperature and humidity of air were investigated. As results of this study, the contamination area of PV cells increases with contamination time and cumulative fine dust density in the air. The contamination of PV cells increases when the temperature is low and the humidity is high. Also, as the contamination of PV cells is affected to the wind, the deviation of contamination area is happened.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.155-156
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• 2015

버섯은 높은 단백질, 낮은 칼로리 있으면서 풍부한 비타민, 미네랄 등을 포함해서 건강식품으로 큰 주목을 받고 있다. 버섯은 인공재배 시에 온도 이외의 또 하나 중요한 요소는 습도이다. 현재 연구 중에 버섯과 온도의 상관관계에 대한 연구 많으며 버섯과 습도의 상관관계에 대한 연구를 상대적인 부족하다. 본 논문에서는 각 습도별에 버섯의 생장상태에 대한 관찰하고 분석한다. 버섯의 수율 및 품질을 개선하기 위해 데이터를 제공할 수 있다.

• 복식
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• 제63권5호
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• pp.102-114
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• 2013

This study performed the evaluation of skin temperature, heart rate, humidity and temperature inside clothing, and subjective sensation to estimate the physiological responses of the human body and its feeling of comfort for developing value-added dox fabric. Experiments were performed on five healthy adult women whose average age was 21, at climate chamber in which temperature, relative humidity and air current were set up below $28{\pm}5^{\circ}C$, $50{\pm}10%$, 0.2m/s, respectively. Two kinds of clothes were used for the experiments: 100% cotton and dox clothes. The clothes were identical in size and form, and the attire consisted of long-sleeved shirts, long trousers, and socks. The experiment was performed for 30 minutes using ergometer. The results are as follows. 1) It showed low skin temperature of forearm, breast, back, forehead and lower leg in exercise, but high skin temperature of them in recovery. However skin temperature of thigh and foot increased from rest to recovery. 2) It showed significant difference (p<0.001, p<0.01) in average skin temperature between cotton and dox clothes. Cotton clothes had a higher average skin temperature compared to dox. Not only was there a significant difference in temperature inside clothing (p<0.001), this was also the case with humidity inside the clothing (p<0.001).

• 한국연초학회지
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• 제23권1호
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• pp.19-30
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• 2001

This study was carried out to investigate the influences of environmental condition in storage room, moisture content and packing weight of leaf on the carbonization of processed flue-cured leaf tobacco, and find out a regression model able to pre-estimate the degree of carbonization. The influence of temperature and humidity in storage room on the carbonization was high,, while that of packing weight was relatively low, However, high moisture content and packing weight of leaf accelerated the carbonization under the high temperature and humidity condition. Thus the leaf tobacco under the condition of 4$0^{\circ}C$, 7$0^{\circ}C$ R.H. in storage room, 16% moisture content and 286 kg/box of packing weight could be carbonized within one month. The pH, total sugar content, lightness(L) and yellowness(b) of leaf were closely related to carbonization of leaf during storage. There were significant regression and yellowness of leaf. It is considered that the certification and/or pre-estimation of carbonization during storage may be possible by applying the regression equation.

• 보존과학회지
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• 제38권1호
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• pp.72-79
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• 2022

A paulownia wood has been widely used with various advantages as its low weight, permeability, convenient workability and aesthetic patterns for a long time. However, the related empirical researches and simultaneous evaluations of functionality are insufficient compared with acid-free archival boxes for now. In this study, the indoor and outdoor temperature and relative humidity control and heat release rate were evaluated under the controlled and uncontrolled circumstance in 2018. The paulownia wood storage box showed superior control effect of relative humidity than the acid-free archival box in constantly uncontrolled environment. Also, the possibility of the flame diffusion from the surface of the materials was higher for the paulownia materials, and the acid-free archival box showed more dangerous patterns in the early stages of the fire.

• 한국ITS학회 논문지
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• 제21권4호
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• pp.157-166
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• 2022

IoT 기술 중에서 가장 많이 쓰이는 무선 통신 기술에는 ZigBee, WiFi, Bluetooth, Z-Wave 등이 있다. 그 중에서 Z-Wave는 현재 세계 시장 점유율이 60%로 선호하는 기술 중 하나이다. 본 논문에서는 Z-Wave 프로토콜을 이용한 온습도 센서 모듈을 구현하였다. 온습도 센서 모듈의 동작을 위하여 Z-Wave 프로토콜을 분석하고, 컨트롤러 모듈의 펌웨어를 탑재하여 구현하였고, 센서 모듈은 데이터 시트를 참고하여 설계 및 제작하였다. 또한 센서의 온습도 정보를 모니터링하는 프로그램을 개발하여 이를 확인하였으며, Z-Wave 모듈의 통달거리 시험, 수신데이터 성공률, 저전력 시험 등을 통하여 성능을 확인하였다.

• 폴리머
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• 제36권2호
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• pp.169-176
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• 2012

저항형 습도센서의 개발을 위하여 스크린 인쇄방법으로 glass epoxy(GE) 기재 위에 핑거의 수와 그 사이의 간격이 다른 여러 가지 바이트형의 금 전극을 제조하였다. 전극의 기본적인 구조는 핑거 수가 3, 4 및 5를 가지며 간격은 각각 310과 460 ${\mu}m$이다. 전극은 처음에 은 나노 페이스트로 전극 패턴을 인쇄하고 연속적으로 Cu, Ni 및 Au를 무전해 도금을 진행하여 제조하였다. 감습성 고분자 전해질은 [2-(methacryloyloxy)ethyl] dimethyl benzyl ammonium chloride(MDBAC)과 methyl methacrylate(MMA)의 공중합체를 사용하였으며 스크린 인쇄 방법으로 Au 전극/GE 기재 위에 인쇄하였다. 이렇게 제조된 습도 센서의 20-95%RH 영역의 상대습도 대 로그 임피던스 그래프에서 좋은 직선성을 보여주었으며 히스테리시스는 1.5%RH 이하 및 75초의 응답 및 회복 속도를 보여주었다. 전극의 구조는 고분자 저항형 습도센서의 감습특성에 큰 영향을 미치며 전해질 고분자와 전극 사이의 활성화 에너지, 온도의존성, 감도, 직선성 및 히스테리시스와 같은 감습특성 등의 차이를 비교하였고 특히 이온의 이동에 관여하는 활성화 에너지 및 온도 의존성에 큰 영향을 미쳤다.