• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.153-156
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• 2001

The transformer and the OF cable are cooled and insulated by insulating oils in their body. The insulating oil expands or contracts with the heat transfer according to the operating conditions of the electric facilities. So we install the $N_2$ gas tank connected with the insulating oil system to overcome the change. The change of the insulating oil volume for the operation temperature range must be calculated to decide the $N_2$ gas volume and to set the alarm point for safe operation. It is known that this change is proportional to the temperature change and to the insulating oil volume if the temperature change is small enough.[1][11] However this proportional formula has been accepted generally in the design of electric facilities for wide operation temperature range such as $40^{\circ}C{\sim}125^{\circ}C$. Hence, it makes large errors in calculation which car result in serious damage against safe operation of the electric facilities. This paper presents a improved method of calculating the accurate change of the insulating oil volume to insure the safe operation of electric facilities.

• Agricultural and Biosystems Engineering
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• v.3 no.2
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• pp.65-72
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• 2002

Temperature is the most influential environment parameter which affects the quality change of agricultural products in cold storage. Therefore, it is essential to keep the uniform temperature distribution in the storage room. This study was performed to analyze the air movement and temperature distribution in the forced recirculating cold storage facility and to simulate optimum storage method of green groceries using 3-D CFD(three dimensional computational fluid dynamics) computer simulation which applied the standard $textsc{k}$-$\varepsilon$ turbulence model and FVM(finite volume method). The simulation was validated by the experimental results for onion storage and the simulation model was used to simulate the temperature and velocity distribution in the storage room with reference to the change of storage method such as location of storage, no stores, bulk storage, and pallet storage. In case of no stores, internal airflow was circulated without stagnation and consequently air movement and temperature distribution were uniform. In case of bulk storage, air movement was stagnated so much and temperature distribution of onion was not uniform. Furthermore, the inner temperature of onion roses more than the initial temperature of storage. In case of pallet storage, air movement and temperature distribution of onion were so uniform that the danger of quality change was decreased.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.441-448
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• 2011

The energy consumption of a condensing gas boiler may be greatly reduced by the effective operation of the unit. In this study, the supply water algorithm for a condensing gas boiler control was developed by using the fuzzy logic. This includes the supply water set temperature algorithm, and the control algorithms of a gas valve, a blower and a pump. For the set temperature algorithm, the outside air temperature and the return water temperature were used as input variables. The supply water temperature difference and its slope were used as input variables of the gas valve and blower control algorithm. And the supply water temperature and the return water temperature were used as input variables of the pump control algorithm. In order to analyse performances of these algorithms, the dynamic model of a condensing gas boiler was used. The initial start-up test, the supply water set temperature change test, the outside air temperature change test, and the return water temperature change test were performed. Simulation results showed that algorithms developed in this study may be practically applied for the effective control of a condensing gas boiler.

• Transactions on Control, Automation and Systems Engineering
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• v.3 no.2
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• pp.133-138
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• 2001

This paper describes a system that can used to recognize an unknown material regardless of the change of ambient tem-perature using temperature response curve fitting and fuzzy neural network(FNN). There are some problems to realize the recogni-tion system using temperature response. It requires too many memories to store the vast temperature response data and it has to be filtered to remove noise which occurs in experiment. And the temperature response is influenced by the change of ambient tempera-ture. So, this paper proposes a practical method using curve fitting the remove above problems of memories and nose. And FNN is propose to overcome the problem caused by the change of ambient temperature. Using the FNN which is learned by temperature responses on fixed ambient temperature and known thermal conductivity, the thermal conductivity of the material can be inferred on various ambient temperature. So the material can be recognized by the thermal conductivity.

• Journal of Climate Change Research
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• v.4 no.2
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• pp.189-199
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• 2013

Using meteorological data collected from 60 observation stations during the last 38 years from 1973 through 2010, we have analysed the occurrence frequencies of abnormally low or high temperature leading to agrometeorological disasters. The analysis was made for 20 agro-climatic zones that had already been divided by the Rural Development Administration before. Since 1973, there have been an average of 1.8 frequency of abnormal air temperature occurrence per year. The frequency of abnormally high temperature occurrence has increased from an average of 0.2 per year in 1970s to 1.0 in 2000s. However, the frequency of abnormally low temperature occurrence has decreased from an average of 2.06 per year in 1970s to 0.63 in 2000s, which might be able to explain a recent global warming. The highest frequency of abnormally high temperature occurrence appeared in Taebaek Alpine zone with an average of 0.76 frequency per year. Meanwhile, abnormally low temperature was the highest in Western Sobaek Inland zone with an average of 1.43 frequency per year.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.597-605
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• 2000

There has been several usual ways to cure pain in osteological muscle: use oral medicine or injection, or apply medicine to a sore place. The purpose of this study was to examine, by using thermometer and digital infrared thermographic imaging, how much the permeation of aceclofenac, an anodyne and antiphlogistic, into sore skin brought a change to skin temperature after that was' applied to it. The findings of this study were as below; 1. A cream made of aceclofenac yielded $0.61^{\circ}C$ difference in temperature, but the difference wasn't statistically significant. 2. An aceclofenac to which oleic acid was added went through microemulsion and applied, and there was $0.3^{\circ}C$ change in temperature, the biggest significant difference(P<.05), after approximately 15 minutes passed. 3. An aceclofenac to which labrasol was added went through microemulsion and applied, and there was a growing rise in temperature with the lapse of time. After 30 minutes passed, the final temperature showed $1.25^{\circ}C$ rise, which was a significant change(P<.05). 4. As the temperature was measured by digital infrared thermographic imaging, there was about $3.97^{\circ}C$ fall, the biggest change, which was significant(P<.05). The findings of this study suggested that the application of aceclofenac to sore skin caused a change in skin temperature, as that permeated into it.

• Journal of the Korean Geographical Society
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• v.46 no.2
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• pp.152-167
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• 2011

This study aims to investigate the change of seasonal trend appeared in the daily normals of wintertime daily mean temperature of Seoul for 1941~1970 and 1971~2000 and the factors to affect it. The lowest temperature in wintertime is appeared in the period of the first and second ten-days of January in the daily normals for 1941~1970 and in the third ten-days of January and the first ten-days of February for 1971~2000. This means seasonal trend was changed. This change is due to the fact average temperature from 27 December to 20 January is rising much more than the wintertime mean temperature and average temperature from 21 January to 9 February less than that for two daily normals. This features are notable after 1971. The Siberian high and norther wind around the Korean Peninsula are weakened remarkably recently, so mean temperature of Seoul from 27 December to 20 January is warming much more. On the other hand, the Siberian high from 21 January to 9 February is weakened and the Aleutian low is strengthened recently and northerly is not change obviously, so temperature of Seoul is not warming so much.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.481-485
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• 2014

According to statistical data the past ten years, cultivation area and yield of radish are steadily decreasing. This phenomenon cause instability of radish's supply due to meteorological chage, even if radish's yield per unit area is increasing by cultivation technological development. These problems raise radish's price. So, we conducted study on meteorological factors for accuracy improvement of radish yield estimation. Panel analysis was used with two-way effect model considering group effect and time effect. As the result, we show that mixed effects model (fixed effect: group, random effects: time) was statistical significance. According to the model, a rise of one degree in the average air temperature on August will decrease radish's yield per unit area by $428kg{\cdot}10a^{-1}$ and that in the average air temperature on October will increase radish's yield per unit area by $438kg{\cdot}10a^{-1}$. The reason is that radish's growth will be easily influenced by meteorological condition of a high temperature on August and by meteorological condition of a low temperature on Octoboer.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.1
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• pp.32-36
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• 2009

The ice storage system uses water for low temperature latent heat storage. However, a refrigerator capacity is increased and COP is decreased due to supercooling of water in the course of phase change from solid to liquid. This study investigates the cooling characteristics of the TMA-water clathrate compound including TMA (Tri-methyl-amine, $(CH_3)_3N$) of $20{\sim}25wt%$ as a low temperature latent heat storage material. The results showed that the phase change temperature and the specific heat is increased and the supercooling degree is decreased as the weight concentration of TMA increased. Especially, the clathrate compound containing TMA 25 wt% has the average phase change tempera ture of $5.8^{\circ}C$, the supercooling degree of $8.0^{\circ}C$ and the specific heat of 3.499 kJ/kgK in the cooling process. This can lead to reduction of operation time of refrigerator in low temperature latent heat storage system and efficiency improvement of refrigerator COP and overall system. Therefore, energy saving and improvement of utilization efficiency are expected.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.23-28
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• 2007

In most existing research, it is difficult to evaluate thermal comfort exactly because of reflecting individual ideal or psychological response by subjective questions. Physiological variable was selected in this study to evaluate objectively thermal comfort. MST was appeared very sensitively in indoor temperature and can express correctly thermal comfort of human body. The results of CSV are different each individual feeling sensation, so is difficult to evaluate detailedly thermal comfort unlike TSV. But the results of PP, AIx, ED, SEVR are greatly related to temperature change. So thermal comfort is evaluated more objectively by using PP, AIx, ED, SEVR on behalf of TSV, CSV. Human body was presented physiological feedback by temperature impetus and specially, tendency of heart rate agree with temperature change. Physiological reaction was showed sufficient possibility availing evaluation index of thermal comfort. In the future another one needs to review beside the selected physiological variable.