• Journal of the Korean Society for Heat Treatment
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• v.24 no.1
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• pp.10-15
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• 2011

Recently, renewable energy sources such as wind turbine, solar cell are interested in preventing global warming which is caused by the consumption of fossil fuel. SCM440(H) and SNCM439 have been used in the major components of the wind turbine gear because of excellent mechanical properties. In the present study, the heat treated mechanical properties of SCM440(H) and SNCM439 with 150 mm diameter were compared with those with 25 mm diameter which is generally accepted material for structural application. Heat treated SCM440(H) showed better mechanical properties such as tensile strength, hardness and impact absorbed energy compared with those in SNCM439. Hardenss value between as-quenched and as-quenched followed by tempering showed big difference in SNCM439, however the difference in SCM440(H) was relatively small. Heat treated mechanical properties of the alloys with 25 mm diameter were more uniform value than those with 150 mm diameter.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.8
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• pp.24-30
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• 2019

This study investigated the heat dissipation characteristics of a heat-sensitive LED. The results of the empirical test showed that the best temperature intensification was found at 90 with 15-fins, and the heatsink installed perpendicular to the direction of the flow of air was directly connected to the air in the largest heat shield area, leading to the best cooling, and the number of fin also resulted increase in the heat discharge area, resulting in the largest cooling action with 15 fins. It was found that the rate of air flow changed in the range of 1.5m/s to 2.5m/s, but only by a deviation of about $2^{\circ}C$ to $3^{\circ}C$ from the current state of 15 fins at 2.5m/s, and the rate of air flow increased, but the performance of the heat release was not significantly increased. As a result wind speed with minimum air flow conditions of 1.5m/s can greatly contribute to the heat dissipation performance.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.148-151
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• 2004

The hardening of concrete after setting is accompanied with nonlinear temperature distribution caused by development of hydration heat of cement. Especially at early ages, this nonlinear distribution has a large influence on the tensile cracking. As a result, in order to predict the exact temperature distribution in concrete structures it is required to examine thermal properties of concrete. In this study, the coefficient of air convection for concrete mix of nuclear power plant, which presents thermal transfer between surface of concrete and air, was experimentally investigated with variables such as velocity of wind and types of form. The coefficient of air convection obtained from experiment increases with velocity of wind, and its dependance on wind velocity is varied with types of form. This tendency is due to a combined heat transfer system of conduction through form and convection to air. The coefficient of air convection for concrete mix of nuclear power plant obtained from this study was well agreed with the existing models.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1147-1148
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• 2006

The increase of exhaust gas which is caused by with the industry activity which follows in the Industrial Revolution of the human being has had an influence on the globe climate system so that causes the problem of the greenhouse effect. As a comprehensive countermeasures, it has been prompted to save energy, build a structure environmentally friendly and use renewable energy sources that are continually replenished by nature-the sun, the wind, the Earth's heat, and plants. In addition, new technologies that turn these fuels into usable forms of energy-most often electricity, but also heat, chemicals or mechanical power have been applied actively to the social infrastructure. Therefore, there should be methods to manage forms of renewable energy effectively and securely. This paper proposes the web-based monitoring system for the wind power system of these methods and introduces the real web-based monitoring system installed in Daegwallyeong.

• KIEAE Journal
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• v.12 no.2
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• pp.117-124
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• 2012

The purpose of this study is to investigate the change of wind environment for different building arrangement. In this study, we analyze outdoor wind environment on different building arrangement that take same floor area ratio using the CFD (Computational Fluid Dynamics) method. We do not consider the effect of temperature. Building arrangements of low density, different hight and a lot of green area will change the effect of wind environment. The eight different arrangements of buildings are studied in this paper. In these calculations, we know the different arrangement of buildings change outdoor wind environments. Especially, reducing the number of building and crossing the different height of buildings have a good kind of wind environment at the same floor ratio. We know that these arrangement of buildings to reduce the heat island phenomena on city plan.

• Korean Journal of Oriental Medicine
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• v.2 no.1
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• pp.26-39
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• 1996

The literatual study on the therapy for clearing away heat with apoplexy therapy, the result were obstained as follows. 1. In apoplexy therapy, therapy for clearing away heat is used excessive heart - fire by overacting of the five emotions, liver fire, deficiency of kidney - fluid, wind - heat. 2. The fire of aetiology of apoplexy is used therapy for clearing away eat, in aspect of viscera and bowels, divied into heart - fire, liver - fire, deficiency fie of kidney yin, wetness - phlegm of spleen heat. The treatment is clear away heart - fire, clear away liver - fire, clear away spleen - heat and sthenic water. 3. Symptom of excessiveness symptom - complex is used therapy for clearing away heat that are fever, flushed face, halitosis, heart burn, easy anger, apoplestic stroke, unconsciouness, trismus, paralysis, constipation, red tongue with yellow coat, taut - smooth pulse or full - rapid pulse and symptom of insufficiency symptom - complex that are dizziness, tinitus, blurring of vision, deficiency sleeping, dreaminess, lassitude of the loins and legs, hemiplegia, red tongue with white coat or thin - yellow coat taut - thready - rapid pulse. 4. Therapy for norish vital essence - clearing away heat is availed in excessive fire caused by deficiency of yin of the liver and kidney, therapy for break through phlegm - clearing away heat in stagnant heat therapy for waking up a patient from unconsciousness - clearing away heat in yang type sthenia - syndrom of coma of apoplexy involving viscera and bowels. 5. Commonly used recipes of therapy for clearing away heat are Yang gyolksan(凉膈散), Bang pongtongseongsan(防風通聖散), Sotongseongsan(小通聖散), Jibodan(至寶丹), Supungsungisan(搜風順氣散), Woowhangchengshimwhan(牛黃淸心丸), Chengungsekgong(川芎石膏湯), Samwhatang(三化湯) etc in excessiveness symptom- complex, and are Yukmijiwhangweon(六味地黃元), Jiwhangtang(地黃湯), Palmiji whangtang(八味地黃湯), Samultanggagam(四物湯加減) etc in insufficiency symptom - complex.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.339-350
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• 2000

The three-dimensional new corrdinate system over a single hill double hills and complex terrain with a single hill and a rectangular obstacle was generated using a body-fitted coordinate system. Control of the coordinate line distribution in the field was executed by generalizing the elliptic generating system to Poisson equation. ▽2ξ=P. The new coordinate system was well fitted to the surface boundary of single hill and double hills. But in the case of complex terrain with hill and rectangular obstacle there was smoothing tendency around the rectangular obstacle. In order to show the validity of the body-fitted coordinate system the heat diffusion equation was transformed and the temperature distribution was calculated over the various terrain. The results showed the temperature distribution was very symmetrical and stable around hills and obstacle. As a result the couple of a body-fitted coordinate system and the heat diffusion equation were executed successfully. Wind field over complex terrain with hill and rectangular obstacle which represent urban area was simulated stably in body-fitted coordinate system. The qualitative result show the enhancement of wind speed at the upwind direction of a hill and a rectangular obstacle and the recirculation zone at the downwind direction.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.59-65
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• 2016

MVR evaporation is a method of pressurizing the evaporating steam to raise its temperature with an electric compressor instead of burning fuel and reusing the heat source through the embraced heat exchanger to minimize energy use. MVR desalination system with wind power uses varying wind power instead of stable electricity and can flexibly control the volume of fresh water production. The present study introduces the design, construction and operation of a MVR desalination system of 30ton/day capacity. Experimental results, MVR compression ratio is higher than 1.5, temperature difference of the main heat exchanger is $5{\sim}7^{\circ}C$. This value shows the same performance as the designed value.

• Magazine of the Korean Society of Hazard Mitigation
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• v.2 no.4 s.7
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• pp.40-47
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• 2002

Since it is important to understand the bio-climatic change in Seoul for ecological city planning in the future, this paper gives an overview on bio-climate analysis of urban environments at Seoul. We analyzed its characteristics in recent years using the observations of 24 of Automatic Weather Station (AWS) by Korea Meteorological Administration (KMA). In urbanization, Seoul metropolitan area is densely populated and is concentrated with high buildings. This urban activity changes land covering, which modifies the local circulation of radiation, heat and moisture, precipitation and creating a specific climate. Urban climate is evidently manifested in the phenomena of the increase of the air temperature, called urban heat Island and in addition urban sqall line of heavy rain. Since a city has its different land cover and street structure, these form their own climate character such as climate comfort zone. The thermal fold in urban area such as the heat island is produced by the change of land use and the air pollution that provide the bio-climate change of urban eco-system. The urban wind flow is the most important climate element on dispersion of air pollution, thermal effects and heavy shower. Numerical modeling indicates that the bio-climatic transition of wind wake in urban area and the dispersion of the air pollution by the simulations of the wind variation depend on the urban land cover change. The winds are separately simulated on small and micro-scale at Seoul with two kinds of kinetic model, Witrak and MUKLIMO.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.35 no.4
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• pp.106-122
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• 2022

Objectives : In this study, we aimed to analyze the latest knowledge of pityriasis rosea(PR) through oriental-western medical review on PR. Methods : We searched Pubmed, CNKI, and OASIS to select papers related to the cause, mechanism, diagnosis, classification, treatment, and herbal treatment of PR. Results : The results are as follows. 1. Although the exact cause of PR is not known, it has recently been found that reactivation of latent human herpesvirus-6 and human herpesvirus-7 infection is a possible etiology. Most patients require emollients, antihistamines, topical steroids, and macrolides. Acyclovir, and narrow-band UVB therapy are also used. 2. The cause and mechanism of PR in Chinese and Korean medicine can be mainly summarized as wind-heat, blood heat, and blood deficiency and wind-dryness. Most of the herbal medicine used have the effects of clearing heat, cooling the blood, detoxifying, dispelling wind, relieving itching, nourishing blood, and moistening dryness. Conclusions : In Chinese and Korean medicine, it is necessary to organize the representative prescriptions according to pattern identification, and it is also necessary to study the atypical types of PR and its treatment methods. It is thought that research on oriental and western combination therapy should be continuously conducted, and efforts to develop Korean medicine formulations are needed to revitalize clinical research in Korea.