• Journal of Advanced Marine Engineering and Technology
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• v.38 no.9
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• pp.1027-1031
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• 2014

Free cooling system is used to reduce energy consumption of cooling system. Free cooling system is consisted of cooling group and dry-cooler in which heat exchange of chilled water and out air is conducted. Although this system has an excellent energy saving effect in place having cooling load regularly, data or material of design for free cooling system is lacked. In this study, characteristics analysis of free cooling system is conducted through software HYSYS with changing some facts. The main result is following as : Dry-cooler capacity is influenced by out air temperature, required chilled water temperature and LMTD(Logarithmic Mean Temperature Difference) of heat exchanger. As out air temperature is more low, dry-cooler capacity become increased. in addition, as required chilled water temperature is more high and LMTD is more low, the out air temperature range is widened for using dry-cooler. If out air temperature is below $0^{\circ}C$, antifreeze need to be used because freeze and burst can be occurred. In case of South Korea, antifreeze of 34% of ethylene glycol concentration is proper. When compressor load of R22, R134a and R407C is compared, considering environmental regulation and energy consumption, R134a is best working fluid.

• Journal of Animal Environmental Science
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• v.11 no.3
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• pp.177-188
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• 2005

In this study, the thermal environmental factors in a layer f(arm such as dry bulb temperature, relative humidity, black globe temperature and illumination intensity were measured and analyzed to serve as basis for effective design and plan of poultry houses. The correlation analysis between the different factors was also done. Heat Index as measure of the thermal stress was also calculated and analyzed. A $1,000m^2$ laying house, 4 meters high with 52,000 layers in six-stage type cages was used in the measurement of the different environmental parameters. The results were as follows; 1. The temperature of the inside air and materials was directly related to the increase in aerial temperature based on the dry-bulb, black globe temperature reading. The correlation factor of the outside to inside air based on dry bulb setting was very significant at 0.927 The dry bulb temperature for inside temperature ranged from $19.9\~28.8^{\circ}C\;with\;SD+2.2^{\circ}C$ while that of the outside air was $16.2\~33.1^{\circ}C,\;SD+3.5^{\circ}C$. In addition, the temperature of the inside air was very stable. 2. The black globe temperature of the inside air ranged from $20.1\~28.8^{\circ}C,\;SD+2.3^{\circ}C$ while that of the outside air was $16.2\~47.5^{\circ}C,\;SD+6.0^{\circ}C$. 3. The relative humidity of the outside and inside air was $72.4\~100\;and\;50.2\~85.6\%$ with an average of $89.2\;and\;71.7\%$, respectively. 4. The illumination intensity in the laying house was less than 7 lux, with an average of $1.2\~2.5lux$ relative to height indicating that the laying house was well isolated from outside radiation. 5. The heat index of the inside air of the laying house had a high variation from $20.5^{\circ}C,\;SD+2.5^{\circ}C$ while that of the outside air was $13.1\~45.5^{\circ}C$, with an average of $21.6^{\circ}C,\;SD+6.3^{\circ}C$.

• Journal of Korean Medical classics
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• v.25 no.1
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• pp.89-115
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• 2012

Objective : Blood disease is common these days due to modern man's excessiveness in Yang heat (陽熱) and vulnerability of the Eum blood(陰血). This exposes them to warmheat/ dampness-heat diseases, where pathogenic heat easily penetrates the blood dimension(血分) creating stagnated blood(瘀血). Consequently, pathogenic symptoms in the collateral vessels increase, making it crucial to understand the pathogenic mechanism of the disease. Method : This paper examines the condition and region of the collateral vessel diseases(CVD) according to the blood diseases of Onbyeong, by analyzing each prescription's matching symptom. The disease in question in this paper is 'stagnated blood fixated in the collateral vessels'. Therefore diseases with stagnated blood in the Yang collaterals and Viscera collaterals or viscera themselves from the chapter of "On-Yeok-Ron(溫疫論)", and < Dry Blood-DaeWhangJaChungWhan(大黃蟅蟲丸) > chapter of "Geum-Gue-Yo-Rak(金匱要略)", were examined respectively. Result & Conclusion : The process of CVD according to the blood diseases of Onbyeong can be summarized as follows. First, bleeding in the Yang and Bowel collaterals, then stagnation in the Yang and Bowel collaterals, and finally stagnation in the viscera collaterals or Liver itself. The refractory nature of blood stagnation symptoms of the collateral vessels is mainly due to the characteristics of the collateral vessel itself. In structure, they are very narrow and small, situated at the most terminal part of the body where it is difficult for the Jeong Gi(精氣) to reach. Also, as they are symptomatic of degeneration of Jeong Gi, the root of the disease is very deep. Therefore to resolve blood stagnation in the cases of Ju-Gaek-Gyo and Dry Blood, general approaches using 'Gi communication(行氣)' or 'Blood vitalizing(活血)' medicinals will not suffice. Special medicinals such as crustacean and insects need to be appropriately applied.

• Journal of the Korean Geosynthetics Society
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• v.18 no.1
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• pp.79-89
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• 2019

The field measurement and laboratory experiment were conducted to investigate the effect of reducing the surface temperature of the functional aspect of the heat island phenomenon of the permeable block which is made the recycled synthetic resin rather than the existing concrete permeable block. Field measurement was taken for 3 days in consideration of dry condition and wet condition and laboratory experiment was divided into dry condition, rainfall simulating condition, and wetting condition. The variations of temperature and the evaporation rate of water moisture content after experiment were confirmed. As a result of field measurement, it is confirmed that the surface temperature decreases due to the difference in albedo of the pore block surface rather than the cooling effect due to the latent heat of vaporization. The evaporation of moisture in a dry state where drought persisted or a certain level of moisture was not maintained in the surface layer. As a result of laboratory experiment, resin permeable block gives higher surface temperature when it is dry condition than concrete permeable block, but the evaporation of water in the pore is kept constant by capillary force in rainfall simulation condition, and higher temperature reduction rate. As a result of measuring the evaporation rate after laboratory experiment, it is confirmed that the effect of reducing temperature is increased as the evaporation rate of water is higher. Based on these results, correlation formula for evaporation rate and temperature reduction rate is derived.

• Journal of the Korean Society for Heat Treatment
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• v.27 no.2
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• pp.65-71
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• 2014

SMF9060 material is a Fe-based powder sintered alloy that is used for several automobile components such as Synchronize Hub, oil pump and transmission. These components are required excellent wear resistance and durability. In this study, we have performed a dry wear test at the ambient air and Ar gas conditions in the room temperature, and a lubricant wear test at the room temperature and engine oil temperature of $100^{\circ}C$. The amount of wear volume and coefficient friction are measured by a Profilometer and a Ball on disk type wear tester. The wear volume in Ar gas condition was a little higher than that in the ambient air condition. However the wear volume in the lubricant wear condition was much lower than in the dry wear condition. XRD analysis of the debris in Ar gas condition showed that the oxide film was not formed.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.7
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• pp.819-825
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• 2014

The diurnal range of temperature in korea is increasing. We know that the environment has deteriorated through report about railway damage and economic loss caused by climate. In these conditions, Monitoring device for railway must operate to support the operations and maintenance. Therefore, In this paper, COM-based monitoring device implemented using Industrial-Extended electronic components and made, We tested compliance about temperature environment of actual railway. We verified through testing about cold and dry heat of monitoring device. Used components in this product will be able to utilize the development of the railway industry of electronics.

• Journal of Mechanical Science and Technology
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• v.18 no.6
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• pp.990-1001
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• 2004

The retention of a molten pool vessel cooled by internal vessel reflooding and/or external vessel reactor cavity flooding has been considered as one of severe accident management strategies. The present numerical study investigates the effect of both internal and external vessel mixed cooling on an internally heated molten pool. The molten pool is confined in a hemispherical vessel with reference to the thermal behavior of the vessel wall. In this study, our numerical model used a scaled-down reactor vessel of a KSNP (Korea Standard Nuclear Power) reactor design of 1000 MWe (a Pressurized Water Reactor with a large and dry containment). Well-known temperature-dependent boiling heat transfer curves are applied to the internal and external vessel cooling boundaries. Radiative heat transfer has been considered in the case of dry internal vessel boundary condition. Computational results show that the external cooling vessel boundary conditions have better effectiveness than internal vessel cooling in the retention of the melt pool vessel failure.

• Culinary science and hospitality research
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• v.17 no.4
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• pp.273-284
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• 2011

The essential oil obtained by steam distillation from a medicinal plant of Artemisia princeps. The essential oil was analyzed by GC-MS. The heat treatments in roasted condition of temperatures were $80^{\circ}C$, $110^{\circ}C$, and $230^{\circ}C$, and the lengths of the time were 6 min, 10 min, and 14 min, respectively. The blanching conditions($100^{\circ}C$) of the treatments lasted 1 min, 2 min, and 5 min while the times of oven dry ($50^{\circ}C$) was 5 min. As the result, the essential oil content of the control plot was higher than the others, and that of the roasted ones was the second highest in low temperature with short treatment time. The major components were eucalyptol, cyclohexadience, phenol, terpineol, and caryopbyllene.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.39-44
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• 2009

Geothermal energy is the heat contained in the earth and its internal fluids. Geothermal energy is stored as sensible or latent heat. Supplied by both internal and external sources, it represents a vast supply which is only started to be tapped for generation of electric power. In general, this is natural dry or wet medium to high enthalpy steam at temperatures above $150^{\circ}C$. For some time, binary systems employing substances with a lower boiling point than water in a secondary circuit have been used to generate vapor for driving turbines at a lower temperature level. The utilization of binary plants and the possibility of production from enhanced geothermal systems can expand its availability on a worldwide basis. The geothermal electricity installed capacity is approaching the 10,000GW threshold. Geothermal energy is not present everywhere, but its baseload capability is a very important factor for its success.

• Journal of the Korean Society for Heat Treatment
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• v.29 no.6
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• pp.284-291
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• 2016

High temperature alloy steel such as Ni-Cr-Mo-V material has excellent properties of high strength and high heating resistance. It has been used for several military weapon components such as gun barrel of a warship, turbine rotor and turbine disk for nuclear power plant. Being curious about this material required excellent wear resistance and durability in extreme environmental conditions. A dry wear test at the ambient air and Ar gas conditions in the room temperature were performed in this study. What's more a lubricant wear test at different temperature was conducted. In addition that DLC was coated on Ni-Cr-Mo-V alloy steel substrate with a thickness of $3{\mu}m$, a property of it was compare with lubricant conditions. All the coefficient of friction and wear volume, comparing with DLC coated specimens. The test parameters were selected as follows: 10 N for normal load; 80 rpm for sliding wear speed; and 300 m for the sliding wear distance.