• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.11
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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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.5
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• pp.394-402
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• 2007

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 from 2001 to 2005 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.

• Food Science and Preservation
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• v.9 no.2
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• pp.137-143
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• 2002

Temperature and humidity are the most important factors and should be effectively controlled for the cold storage of graius. Fuzzy logic can be easily implemented to the MIMO(Multi-Input Multi-Output) control systems. For the cold storage in grain bin, fuzzy logic was applied to an air conditioning system. The capacities of the grain bin and the air conditioner are 80 tons and 30㎾, respectively. Also, the target values of temperature and relative humidity in outlet duct of the air conditioner were 8$\^{C}$ and 75%, respectively. In order to control temperature and relative humidity of air, a damper in inlet duct was manipulated for temperature control and a heater was used for humidity control. Temperature deviation and change of temperature deviation were used as input parameters for the fuzzy system. Humidity was only considered as a load. The experimental results showed that the controlled temperature of exhausted air was maintained at 8$\pm$2$\^{C}$. Relative humidity of the air was also controlled at the target relative humidity of 50∼80%.

• Journal of Sensor Science and Technology
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• v.21 no.6
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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.

• Current Optics and Photonics
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• v.7 no.5
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• pp.504-510
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• 2023

An optical fiber dislocation fusion humidity sensor coated with graphene quantum dots is investigated. A Mach-Zehnder interferometer is fabricated with three dislocated single-mode fibers with graphene quantum dots coating humidity-sensitive materials. Humidity response experiments showed a good linear response and high sensitivity with easy fabrication and low-cost materials. From 22% to 98% RH, the humidity response sensitivity of the sensor is 0.24 dB/% RH, with 0.9825 linearity. To investigate the cross-response of humidity and temperature, temperature response experiments are conducted. From 30 ℃ to 70 ℃, the results showed 0.02 dB/℃ sensitivity and 0.9824 linearity. The humidity response experimental curve is compared with the temperature experimental curve. The big difference between humidity sensitivity and temperature sensitivity is very helpful to solve the cross-response of humidity and temperature. The influence of temperature fluctuations in humidity measurements is not obvious.

• Architectural research
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• v.9 no.2
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• pp.37-45
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• 2007

The proliferation of the House Dust Mite(HDM) is affected by temperature, humidity, ventilation, etc. Measuring temperature and humidity was performed at the very location where dust samplings take place and where they live in reality together with temperature and humidity of the ambient of the room. There has been discussion over the key environment factor of HDM survival; absolute humidity or relative humidity. It seems that relative humidity is the more important determinant for the mite's survival through the analysis of previous studies. Temperature, humidity, ventilation rate and Der P1 were measured in 4 flats in London. Mite allergen was detected in every house. Levels of Der P1 varied between <100ng/g and 22,778ng/g. Flats with high relative humidity(>50%) and poor ventilation(<0.5ach) showed higher levels of mite allergen than flats with lower humidity and adequate air change rate. Questionnaire survey was conducted and the result helped to confirm the findings from monitoring of environmental factors and the dust sampling.

• International Journal of Aeronautical and Space Sciences
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• v.3 no.1
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• pp.9-18
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• 2002

Thermal humidity characteristics were considered theoretically and experimentally. A Simply well-fitted correlation of a saturated vapor pressure-temperature curve of water was introduced based on Antoine equation to make theoretical prediction of relative humidity according to temperature variation. Characteristics of dew point were also examined theoretically and its relation with temperature and humidity was evaluated. The exact mass of water vapor in a specified humidity and temperature condition was estimated to provide useful insight into the idea about how much amount of water corresponds to a specified humidity and temperature condition in a confined system. A simple but well-fitting model of dehumidification process was introduced to anticipate the trend of relative humidity level during GN2(gaseous nitrogen) purge process in a humidity chamber. Well-suitedness of this model was also verified by comparison with experimental data. The overall appearance and specification of two thermal humidity chambers were introduced which were used to perform various thermal humidity tests in order to yield useful data necessary to support validity of theoretical models.

• Journal of Conservation Science
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• v.29 no.4
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• pp.311-320
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• 2013

The showcase has insufficient temperature control, but it has excellent humidity control. The annual average temperature and relative humidity inside the showcase was $18.8^{\circ}C$ and 60.3%, respectively, and the showcase showed lower temperature and higher humidity than the exhibition room. The temperature inside the showcase appeared with high variation according to the seasons, while relative humidity was ranging from 59% to 61% regardless of the seasons. The showcase showed high temperature and humidity likewise the exhibition room in summer. In addition, lowering of temperature was elevated relative humidity according to the operation of air conditioner in summer. A moisture problem occurred because the temperature and humidity differences between the exhibition room and showcase were large according to the operation of air conditioner in winter. PI for temperature and relative humidity inside the showcase is 18.0%, and it means conservation environment for exhibition is unsuitable. In particular, continuous management of temperature and humidity inside the showcase is required because PI in the summer and winter is less than 1.0%.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.120-125
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• 2003

For this study grasp coverage condition and forest stratification to various green space, observed air temperature and relative humidity. With this data, coverage condition and air temperature, relative humidity distribution, analyzed relationship of forest rate and air temperature or relative humidity, tree numbers and green volume and humidity by revolution analysis. In this result, higher none is formed artificiality and barren area, lower zone did fores and water area. Relative humidity have corresponding type of air temperature distribution. lower Tone was higher humidity. Different of Idlest type or water area, surround of forest showed relatively higher humidity. Increasing tree numbers or green volume effect higher humidity and this efficiency order of an arbor, subarbor, shrub.

• Journal of Mechanical Science and Technology
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• v.20 no.4
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• pp.505-512
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• 2006

This paper presents an integrated multifunctional sensor based on MEMS technology, which can be used or embedded in mobile devices for environmental monitoring. An absolute pressure sensor, a temperature sensor and a humidity sensor are integrated in one silicon chip of which the size is $5mm\times5mm$. The pressure sensor uses a bulk-micromachined diaphragm structure with the piezoresistors. For temperature sensing, a silicon temperature sensor based on the spreading-resistance principle is designed and fabricated. The humidity sensor is a capacitive humidity sensor which has the polyimide film and interdigitated capacitance electrodes. The different piezoresistive orientation is used for the pressure and temperature sensor to avoid the interference between sensors. Each sensor shows good sensor characteristics except for the humidity sensor. However, the linearity and hysteresis of the humidity sensor can be improved by selecting the proper polymer materials and structures.