• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.1
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• pp.48-54
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• 2014

A refrigeration dehumidifier with a recuperative heat exchanger is theoretically analyzed. The recuperative heat exchanger is located between the two air streams from and to the dehumidifying coil, and reduces the sensible heat load in dehumidification process. A simple model is developed to predict performance of the dehumidifier. The model predicts that the recuperative heat exchanger is effective especially in the low humidity condition, where the sensible heat load is relatively large. It is predicted that, by adopting a recuperative heat exchanger, a maximum 30~110% increase in COP is possible for indoor air at $27^{\circ}C$, and 40~60% relative humidity.

• Journal of the Korea Furniture Society
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• v.24 no.3
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• pp.239-246
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• 2013

Recently the building is introducing the indoor water space. Thermal environment change with the introduction. Consequently, this study shows how water space in the public facility affects the indoor environment. We had put our experiment to measure the humidity and temperature differences in different distances of water space. The result of this study is as follows. First, We found that even though there's a water space, it makes no big change in temperature by different distance. The temperature was only maintained by a cooler. Second, As there's a water space, the humidity was affected by within 1.5 m of it. Through our experimental result, we have started our study to make a water space effective.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.205-210
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• 2005

Ice storage system stores cold energy using ice, which is used for cooling on next day. Ice storage system is the effective cooling system that uses cheep electric energy during a night, and also suppresses the peak load of electricity. In this study, the normalized temperature, relative humidity and specific humidity are analyzed using the weather data for past five years in order to estimate the cooling load for the control of ice storage system. The calculated cooling loads show fairly good agreement with the measured data of model hospital, especially at the outdoor design temperature of $25^{\circ}C$.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.3
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• pp.368-377
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• 1998

The purpose of this study was to examine theory about indoor thermal comfort-environment as well as to determine thermal sensation and physiological responses for men in summer indoor environment, under various air temperature and relative humidity, with male university students. Subjective Evaluation, Heart Rate(Electrocardiogram), Electroencephalogram(EEG) were examined. We found that comfort of people was achieved at SE $T^{*}$ 24.7$^{\circ}C$, -0.82＜PMV＜0.93, subject's clothing(0.41c1o)and the difference of skin temperature was found at the calf area as air temperature changes. At low SE $T^{*}$, heart rate was decreased and at high SE $T^{*}$, heart rate was increased but there was no change EEG(keeping $\alpha$-wave).wave).

• Journal of the Korean Institute of Intelligent Systems
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• v.5 no.1
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• pp.33-42
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• 1995

A practical application of a fuzzy-neuro controller is described for an air-conditioning system. Air-handing units are being widely used for improving the performance of central air-conditioning systems. The fuzzy-neuro control system has two controlled variables, temperature and humidity and three control elements, cooling, heating, and humidification. In order to achieve high efficiency and economical contorl, especially in large offices and industrial buildings, two controllable parameters, temperature and humidity, must be adequately controlled by the three final controlling elements. In this paper a fuzzy-neuro control system is described for controlling air-conditioning systems efficiently and economically. Simulation results confirmed that the fuzzy neuro control system is effective for this multivariable system.

• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.102-111
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• 1997

An In-line dry scrubbing FGD process was investigated. Calcium hydroxide was entrained in flue gas and the SO$_2$ removal efficiency by humidity and additives were examined. The range of reaction temperature was $200^{\circ}C$~$500^{\circ}C$ and the concentration of $SO_2$ was around 900ppm. By the increase of humidity in flue gas, the removal efficiency was increased. The effect of NaOH as a additive was very high and got high conversion of $Ca(OH)_2$, however in case of RH 90%, it was reverse. The effect of particle size and flow rate were examined. And the reaction rate constant and effective diffusivity also calculated.

• Steel and Composite Structures
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• v.47 no.4
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• pp.539-550
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• 2023

Owing to the obstruction of section steel on the moisture diffusion in concrete, the existing shrinkage prediction models overestimate the time-dependent deformation of steel reinforced concrete (SRC) columns, particularly for the SRC columns with enclosed section steels. To solve this issue, this study deals with analytical and experimental studies on the drying shrinkage for this type of column. First, an effective method for predicting the drying shrinkage of concrete based on finite element model is introduced and two crucial parameters for simulation of humidity field are determined. Then, the drying shrinkage of SRC columns with enclosed section steels is investigated and two modified parameters, which depend on the ambient relative humidity and the ratio of section steel size to column size, are introduced to the B3 model. Finally, an experiment on the shrinkage deformation of SRC columns with enclosed section steels is conducted. Comparing the predicted results with the experimental ones, it demonstrates that the modified B3 model is quite reasonable.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.811-816
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• 2009

Along with research into the latest preservation treatments for items of cultural heritage, studies of the preservation environment and the effect of damage are also increasing. This study conducted comprehensive research into the temperature, humidity, acids, ammonia, reduced sulfur compounds, aldehydes with various ingredients in the exhibition hall, show case, and storage of three type museum. As a result, temperature, humidity, TVOCs, acetaldehyde frequently exceeded the domestic and international standards for a museum preservation environment and indoor air quality. Also, formaldehyde, chloride, and ammonia exceeded the standards intermittently. Temperature, humidity, TVOCs, acetaldehyde were evaluated to be the major influential factors. In order to control the major factors, apart from temperature and humidity, that cause damage in the museum environment, it is deemed necessary to complement this system with an effective air filter or remover.

• Food Science of Animal Resources
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• v.18 no.2
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• pp.176-184
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• 1998

The objective of this study was to investigate the effects of freezing rate on aroma retention and to examine the mechanism of aroma retention during freeze drying process. Our experiments were carried out with self-manufactured freeze-dryer. Gelatin gels (2% w / w, 80${\times}$20mm) containing diacetyl(2mg/ml) were frozen unidirectionally (Neumann's model) from the bottom at -45, -30, -20, and -15$^{\circ}C$ and followed with freeze-drying. Under the upper conditions we measured freezing rate and the change of temperature and pressure during freeze drying. Freeze-dried gelatins were cut horizontally into 5 mm thickness from the bottom measured and diacetly contents. Besides, we observed the effect of the relative humidity of the diacetyl contents freeze-dried gelatin during storage. The retained diacetyl content was increased at high freezing temperature and in order of 0∼5, 5∼10, 10∼15, 15∼20 mm section from the bottom of the sample. It was observed that the retained diacetyl content was high in 15∼20 mm section. The retained diacetyl content and freeze-dried gelatin stored in the condition of high relative humidity was decreased significantly but in the low relative humidity case, was it decreased in small amount. The results of our experiment resents that the low temperature freezing and low humidity storing condition is effective for preserving aroma compound in food.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.1
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• pp.118-125
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• 2016

This paper proposes the appropriate waterproofing methods for underground structures after applying different types of waterproofing materials on the concrete test specimens and selecting the best results out of humidity testing in winter conditions. Results of the testing showed that the underground structures absolutely require relevant waterproofing application based on the environmental conditions; when applied with interior waterproofing, the results showed that the concrete maintained high level of humidity and reinforcing steel within the concrete layer corroded. However, when applied with exterior waterproofing, it was shown that the waterproofing layer prevent direct contact with water and concrete, thereby protecting the concrete structure and improving overall durability. It follows that during underground structure construction, exterior waterproofing methods are have shown by an effective method for improving the durability as well as providing a comfortable interior environment for users.