• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.638-644
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• 1999

The objectives of the study are to investigate thermal conductivity(TC) and coefficient of thermal transmission (CTT) according to the type of soils, the presence of reinforceemnt, temperature, relative humidity and to analyze experimentally the characteristics of thermal transfer of reinforced soil wall. Results are summarized as follows ; 1) Clayey soil has high value of TC and CTT than sandy soil. 2) TC and CTT of reinforced soil wall is about 6∼17% higher than those of reinforced one, 3) It is founded that the effect of relative humidity on the soil wall is important at the same temperature and 4) As the temperature is high, it is appeared that TC and CTT are high.

• Journal of Korean Association for Spatial Structures
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• v.23 no.1
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• pp.35-43
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• 2023

Microclimate analysis was conducted through actual measurement according to land use status in urban, and CFD analysis was conducted to analyze and predict the microclimate characteristics of urban, and compared and analyzed with the actual measurement results. It was measured in high-rise areas and parks, and the temperature of the park area was 0.4 to 0.6℃ lower, and the relative humidity was 1.0 to 3.0% higher. The correlation coefficient was obtained by comparing the results of the computational fluid analysis with the results of the computational fluid analysis at the actual location located within the CFD analysis area for validation. The seasonal correlation coefficients are all higher than 0.8, so it is judged that they can be applied to microclimate analysis in urban area. The computational fluid analysis was divided into three areas (low-rise, low and high-rise, and high-rise) centered on the A2 point. On average, the low-rise area was 0.1 to 0.4% higher than the high-rise area. In the low and high-rise area and high-rise area, the pith of buildings are wide, so the airflow is smooth, so it is judged that the temperature is relatively low.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.876-881
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• 2001

DLC(Diamond-like carbon) films possess high hardness, low friction coefficient, and good wear resistance. Due to these properties, DLC films have been used extensively in magnetic hard disk industry. The objective of the present study was to investigate the influence of environmental condition on the tribological behavior of DLC coated hard disk. It is found that the tribological characteristics of DLC films are strongly affected by relative humidity and temperature. Specifically, the friction coefficient increases with increase in temperature at relative humidity of 50%. However, at 20% and 85% RH the effect of temperature was not significant. Also, the degree of wear could be observed using an AFM.

• Journal of Engineering Education Research
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• v.20 no.1
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• pp.63-68
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• 2017

This research is as a case study of innovative engineering education system through idea factory of korea maritime and ocean university and deals with development of temperature-humidity control device (THCD) for fiber storage on composites in viewpoint of problem solving method. Fiber reinforced plastic (FRP) includes many variables on the composite manufacturing process. Above all, the interfacial adhesion between the fiber and the matrix acts as an important thing that decided mechanical property of the FRP, and also it is profoundly linked to external temperature and relative humidity. High void fraction leads to a result in interlaminar fracture. Therefore, in this research, to establish correlation between fiber reinforcement and fiber storage conditions of temperature and relative humidity we developed a THCD for fiber reinforcement. To evaluate performance of the THCD, glass fiber reinforced plastic (GFRP) is made under the extreme conditions each temperature $34^{\circ}C$, relative humidity 98 % and it can be said that there are the change of mechanical properties according to fiber storage conditions. As a result, the THCD showed sufficient possible application for understanding and applied research of composites field in material engineering. Also, we could check that the necessity of introduction of innovative system such as idea factory existed.

• Journal of environmental and Sanitary engineering
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• v.11 no.1
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• pp.9-15
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• 1996

The purpose of this study was to evaluate the decomposition efficiency of $NH_3$ odor gas using high frequency surface discharge body. The results from this study are as follows; 1, Voltage and frequency of electric elements have effects on removal of $NH_3$ odor. The higher these two elements were set up, the more efficiently deodorizing processing worked. In this experiment, the optimum voltage and frequency applicable were observed around AC 6.0 kVp-p and 24.0 kHz respectively. 2. The temperature, humidity and residence time were observed strong variables for NH$_3$ removal process. Its performance had limits at high temperature and humidity conditions. The longer the residence time continued, the more efficiently deodorization process worked. The experimental results showed that the deodorization was efficiently processed under such conditions as $30.0^{\circ}C$ in temperature, 60rh% in humidity and 0.3 sec in residence time. 3. It was observed that in deodorization experiment, $NH_3$ odor gas was perfectly decomposed under the concentration condition below 15.0ppm. Moreover it was considered as economic and practical in terms of maintenance cost when compared with other deodorization methods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.4
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• pp.381-388
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• 1998

Hot and humid weather in summer generally brings about discomfort. Experiments on which relative humidity makes effects on the comfort sensation were performed to the young and the aged using sensation vote. From July to October 1996, seven college students and eleven aged people were exposed for 2 hours under six different conditions in the Pukyong National University test chamber so as to determine the effects of relative humidity on thermal and comfort sensations. Subjects were wearing same clothes, and the mean clo value was 0.5. The mean radiant temperature was equal to the air temperature and air velocity in the occupied zone around 0.lm/s. In the experiments, it was found that discomfort could be largely reduced when the humidity is controlled to low values in the settled high temperature.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.34-38
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• 1994

Effect of temperature, relative humidity (RH) and free water period on anthracnose development by Colletotrichum gloeosporioides was examined on red pepper fruits. Mycelial growth of C. gloeosporioides was best at 28$^{\circ}C$, but greatly retarded at 32$^{\circ}C$. Minimum inoculum density required for lesion development varied with isolates, but was mostly above 1.0$\times$105 conidia/ml. Optimum temperature for lesion development on fruits was 31$^{\circ}C$. Percentage of lesion development was decreased as incubation temperature decreased. similar trend of temperature response was observed for acervulus formation on the developed lesions. Acervuli were not developed on the lesion as low as at 19$^{\circ}C$. Lesion development and acervuli formation tended to increase as increasing RH, but were greatly inhibited at the RH lower than 88%. More than 2 hours of free water period after inoculation were required for lesion development. Lesion development was increased as free water period increased. This study indicates that anthracnose development by C. gloeosporioides favors the conditions of high temperature above 28$^{\circ}C$, high humidity above 90% RH, and requires free water period longer than 2 hours.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.302-307
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• 2000

The wintering honey bee chambers were constructed and inside environment factors were analyzed to provide high technology for efficient wintering of honeybee colonies. As a result of this study, inside air temperature of yongin chamber under the wide range of outside temperature condition was found to be appropriated for wintering of bee, and inside temperature of beehive was about 2$^{\circ}C$ higher than the air temperature in the chamber. The fan operation schedule did not control the high temperature down properly in the chamber, It was necessary to find a new fan operation schedule to be able to provide the optimum temperature for wintering honey bee colonies. inside humidity variation of Yongin chamber was very much depended on outside humidity.

• Journal of Sensor Science and Technology
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• v.26 no.1
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• pp.50-55
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• 2017

The measurement of absolute humidity of gases is essential in many industries. The effect of temperature on aluminum oxide and chilled mirror dew-point hygrometers is investigated. The temperature of laboratory, pipe line, and sensor is varied and the dew point is measured by two different aluminum oxide hygrometers. In all cases, the dew point of hygrometers is increased as the temperature is elevated. The reason behind this observation is due to desorption of water from the inside of pipe line and/or sensor surroundings at elevated temperature that result in the increase of the absolute humidity. Moreover, the sensor itself shows a certain degree of temperature dependency in sensing the humidity especially at low temperature. It is also studied that chilled mirror dew-point hygrometer may indicate a higher dew point than the reference at high temperature because the cooling capability of mirror is decreased at high temperature. Our study will provide evidences in the incorporation of the temperature effect as uncertainty factors in the standard calibration procedure for dew point hygrometers.

• Journal of Applied Reliability
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• v.12 no.4
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• pp.275-285
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• 2012

This paper presents a changes of luminescence property for converted white LEDs with the commercially available silicate phosphor. If silicate phosphor's quantity increase step by step. luminescence property will be changing. we analyze luminescence property for these change and carry out the high temperature aging test for 7,000 hours, the high temperature and humidity aging test for 7,000 hours for reliability. LED degradation not only results in reduced light output but also in color changes. so we monitor correlated color temperature (CCT), chromaticity coordinates(x, y) and spectrum intensity. Those results suggest that humidity factor more bad effect in color changes than temperature factor and Lighting quality is related with quantity of phosphor.