• 아시안잔디학회지
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• 제15권3호
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• pp.111-118
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• 2001

본 연구는 주거지역으로 둘러싸여진 4ha 규모의 녹지를 대상으로 토지피복현황 및 수고의 차이가 기상완화효과에 미치는 영향을 파악하기 위해 녹지 내의 기온 및 상대습도분포를 관측하였다. 그 데이터를 바탕으로 녹지의 토지피복현황과 기온 및 상대습도분포, 토지피복비율 및 수목그루와 기상완화효과와의 관련성을 회귀분석 등에 의해 해석하였다. 그 결과, 고온역은 인공구조물과 나지 주변에 저온역은 수림지와 초지 주변에서 형성되었다. 상대습도는 기온분포에 거의 대응하는 형태로 고온역은 저습역이구 저온역은 고습역으로 나타났다. 토지피복비율별 기상완화효과를 보면, 수림지와 초지율이 증가하면 기온은 떨어지고 상대습도는 상승시키는 효과를 보였다. 또, 수목그루의 증가는 수고에 관계없이 모두 기상완화에 효과적이고 그 효과의 효율은 교목, 소교목의 순이다.

• 센서학회지
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• 제21권6호
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• pp.420-424
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• 2012

We have investigated temperature dependence and long-term change of humidity measurement from 32 relative humidity sensors. The readings of the humidity sensors depended not only the reference humidity, but also temperature of the chamber. Approximately, the temperature dependence of the humidity sensor in average was 0.05 %R.H./$^{\circ}C$ in the temperature range from $5^{\circ}C$ to $55^{\circ}C$. For humidity sensors that have an internal temperature compensation circuit, the resulting temperature dependence was weaker by 20%. It should be also noted that for the humidity sensors used in this work underwent ${\pm}3$ %R.H. change per year for level of confidence of 95%. The users of relative humidity sensors may refer this value as a minimum change when they set the calibration interval of the humidity sensors.

• 대기
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• 제31권3호
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• pp.295-309
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• 2021

Diurnal variations of air temperature and relative humidity in the Urban Canopy Layer (UCL) of the Seoul metropolitan area are examined using the Weather Research and Forecasting model coupled with the Seoul National University Urban Canopy Model. The canopy layer air temperature is higher than 2-m air temperature and exhibits a more rapid rise and an earlier peak in the daytime. These result from the multiple reflections of shortwave radiation and longwave radiation trapping due to the urban geometry. Because of the absence of vegetation in the UCL and the higher canopy layer air temperature, the canopy layer relative humidity is lower than 2-m relative humidity. Additional simulations with building height changes are conducted to examine the sensitivities of the canopy layer meteorological variables to the urban canyon aspect ratio. As the aspect ratio increases, net sensible heat flux entering the UCL increases (decreases) in the daytime (nighttime). However, the increase in the volume of the UCL reduces the magnitude of change rate of the canopy layer air temperature. As a result, the canopy layer air temperature generally decreases in the daytime and increases in the nighttime as the aspect ratio increases. The changes in the canopy layer relative humidity due to the aspect ratio change are largely determined by the canopy layer air temperature. As the aspect ratio increases, the canopy layer relative humidity is generally increased in the daytime and decreased in the nighttime, contrary to the canopy layer air temperature.

• 한국산림과학회지
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• 제94권6호
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• pp.468-475
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• 2005

표고재배사내 시공간적인 온습도 변화를 이해하기 위하여 표고시설재배사내 HOBO H8시리즈 센서를 이용하여 온 습도를 측정하였다. 2003년 10월부터 2004년 10월 까지 얻어진 결과는 다음과 같다. 1. 수평적 온도변화는 재배사내부의 가장자리보다 중앙부분이 더 작았다. 한편 상대습도변화 는 재배사내부의 가장자리보다 중앙부분에서 3%정도가 크게 나타났다. 2. 수직적 온도변화는 온도가 올라갈 때 하단 보다 상단에서 컷으며, 온도가 떨어질 때 하단 보다 상단에서 작았다. 그래서 토양표면에 가까울수록 온도는 작은 변동폭을 보였다. 수직적 상대습도변화는 온도가 올라갈 때 하단보다 상단에서 작았으며, 온도가 떨어질 때 는 하단보다 상단에서 컷다. 결국 온 습도는 재배사내에서 반대경향으로 나타났다. 3. 원목재배사내에서 최저온도는 4월말까지 영하의 온도로 유지되었으며, 최저온도는 5월초 에 비로서 영상온도를 회복하였다. 한편 계절별로 볼때 겨울이 온도변화가 가장 심했으며, 일중 $30^{\circ}C$를 나타냈다. 반면 최저상대습도로서 4월, 5월, 6월에 20%이하를 보였으며, 그 이 후 40%이상을 회복하였다.

• 설비공학논문집
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• 제24권11호
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• pp.759-766
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• 2012

To estimate the cooling load for the following day, outdoor temperature and humidity are needed in hourly base. But the meteorological administration forecasts only maximum and minimum temperature. New methodology is proposed for predicting hourly outdoor temperature and humidity by using the forecasted maximum and minimum temperature. The correlations for normalized outdoor temperature and specific humidity has been derived from the weather data for five years at Seoul, Daejeon and Pusan. The correlations for normalized temperature are independent of date, while the correlations for specific humidity are linearly dependent on date. The predicted results show fairly good agreement with the measured data. The prediction program is also developed for hourly outdoor dry bulb temperature, specific humidity, dew point, relative humidity, enthalpy and specific volume.

• 펄프종이기술
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• 제34권1호
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• pp.46-53
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• 2002

This study was carried out to analyze the effects of preservation temperature and relative humidity to the physical properties of corrugated fiberboard boxes for fruit and vegetable packaging. The preservation temperature did not affect severely to physical properties of corrugated fiber-board. Relative humidity was a major cause of corrugated fiberboard box quality deterioration. The burst and compressive strengths of experimental boxes measured with Mullen high pressure tester and tong crush tester were decreased gradually as relative humidity increased from 55% to 75%. But, the strength properties slightly decreased relative humidity at 75% or higher. This tendency was the greater for single wall (SW) corrugated fiberboard box than that for double wall (DW). It is suggested that development of the water-resistant corrugated fiberboard and box be needed that can be used under the condition of low temperature and high moisture content, which are being employed in the cold chain system.

• 대한지리학회지
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• 제48권1호
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• pp.19-36
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• 2013

이 연구에서는 지난 58년(1954~2011년) 동안의 관측 자료를 보유한 14개 기상관측소의 일평균 상대습도, 일평균 수증기압을 분석하여 도시 규모별 습도 변화를 파악하였다. 연평균 상대습도는 분석기간 동안 지속적으로 감소하는 경향이며, 도시에서 비도시보다 감소하는 경향이 뚜렷하다. 계절별로는 봄철과 겨울철에 상대습도가 감소하는 경향이 뚜렷하고, 여름철에는 변화율이 작다. 연평균 수증기압은 변화 경향이 뚜렷하지 않고, 도시 규모에 의한 변화율 차이가 명확하지 않다. 상대습도와 평균기온 사이에는 음의 관계가 있으며, 도시 규모에 따른 상대습도 차이가 통계적으로 유의하였다. 상대습도와 수증기압 사이에는 양의 관계가 있지만, 도시 규모에 따른 수증기압의 차이가 뚜렷하지 않다. 한국에서 상대습도가 감소하는 경향은 도시화에 의한 기온상승 경향과 상당히 일치하지만, 수증기압의 변화는 뚜렷하지 않다.

• Journal of Biosystems Engineering
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• 제32권4호
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• pp.247-255
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• 2007

During the winter season in Korea, the relative humidity of greenhouse at night often exceeds 90% because air temperature inside the greenhouse is usually controlled using a heater with all of windows closed to minimize heat loss, thereby requiring the use of a dehumidifier that can maintain optimum humidity levels of $70{\sim}80%$ to provide a good growth condition of crops. Also, such a high humid condition can cause the development of a pest, such as insects, fungi or diseases. However, the use of most conventional dehumidifiers for low temperature dehumidification is limited because their performance is degraded due to frost accumulation on the evaporator coil. This study was carried out to develop a refrigeratory-based dehumidifier suitable for low temperature dehumidification in greenhouse cultivation. The developed dehumidifier consists of a condenser and an evaporator installed separately so that relative and absolute humidity levels can be reduced when air passed through the condenser and evaporator, respectively. The prototype dehumidifier showed a dehumidification capacity of $5{\sim}7kg/h$ when air with a temperature of $15{\sim}25^{\circ}C$ and a relative humidity of $70{\sim}95%$ came into the dehumidifier. Under the condition that either temperature or relative humidity was fixed, the amount of condensed water was proportional to the levels of both temperature and relative humidity.

• 한국태양에너지학회 논문집
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• 제36권5호
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• pp.31-50
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• 2016

To develope a greenhouse fog cooling system to control the temperature and relative humidity simultaneously to the target value, a theoretical analysis and experiments were done. The control process includes the measuring of environmental variables, setting and coding of the water and heat balance equations to maintain the target temperature and relative humidity in greenhouse, calculating of the open level of the greenhouse roof window that governs the natural ventilation and spray water quantity, and operating of the motor to open/close the roof window and pump to spray for water. The study results were shown to be very good because the average air temperature in the greenhouse was kept to be about $28.2^{\circ}C$ with the standard deviation of about $0.37^{\circ}C$ compared to the target temperature of $28^{\circ}C$ and the average relative humidity was about 75.2% compared to the target relative humidity was 75% during the experiments. The average outside relative humidity was about 41.0% and the average outside temperature was $27.2^{\circ}C$ with the standard deviation of about $0.54^{\circ}C$. The average solar intensity in the greenhouse was 712.9 W. The wind velocity of outside greenhouse was 0.558 m/s with the standard deviation of 0.46 m/s.

• KIEAE Journal
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• 제1권2호
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• pp.29-36
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• 2001

The main procedure of this study is to compare temperature and relative humidity between Korean traditional house and apartment house. So, the experiments of measuring temperature and humidity were carried out in 6 Korean traditional houses and 2 apartment houses which are located in Honam district. The Korean traditional house has good conservation properties on temperature and much better effective than apartment house on humidity conservation. The results of this study may be used for basic material in revitalizing traditional construction method.