• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.125-129
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• 2004

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss, but it needs some cooling method because heat radiation between each winding is difficult. The life of transformer is significantly dependent on the thermal behavior in windings. Many transformer designers have calculated temperature distribution and hot spot point by FEM(finite element method) to analyze winding temperature rise. In this paper, the temperature distribution and thermal stress analysis of 100kVA pole cast resin transformer for power distribution are investigated by FEM program.

• Journal of Auto-vehicle Safety Association
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• v.11 no.1
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• pp.23-29
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• 2019

Recently, use of composite materials has been increasing for body structures and chassis parts in the car industry because of weight reduction effect and excellent mechanical thermal characteristics. However, application of composite materials in brake system is very difficult because it is hard to obtain enough brake performance due to low heat storage capacity of the composite materials. In this paper, we will present new carbon ceramic composite disc with high flow characteristic. To obtain this characteristic, new vent structures were designed by using ARIZ method and substance-field model analysis. The flow effect of these vent structures on the brake performance was verified by pugh matrix and cooling test. The test results show improvement of cooling performance up to $30^{\circ}C$. Finally, These results will improve brake the reliability of the brake performance for the high performance vehicles and electric vehicles.

• Journal of Korean Clinical Nursing Research
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• v.19 no.1
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• pp.96-104
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• 2013

Purpose: The specific aims of this study were to define fever from the nurse's and physician's perspectives, describe fever management method and decision-making, and identify differences of definition of fever and fever managements between nurses and physicians. Methods: A cross-sectional survey using a 23-item questionnaire was used. A total of 305 nurses and physicians were surveyed, and 246 useful questionnaires were returned. Results: Body temperature of $36.5{\sim}38.3^{\circ}C$ were considered as adult febrile, and fever managements were initiated when the temperature was $37.0{\sim}38.0^{\circ}C$. More than half of the nurses and physicians, made a clinical decision regarding fever managements based on their own experiences. The most frequently used interventions in nursing practice were antipyretics, intravenous hydration, and external cooling. Nurses provided external cooling to lower body temperature than physicians (Z=-4.67, p<.001). Most participants reported that they needed a fever management protocol. Conclusion: Based on the information obtained, nurses respond with sensitivity to lower body temperature. We found significant differences among nurses, between nurses and physicians in approaching care of adult febrile patients.

• Journal of Electrical Engineering and Technology
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• v.7 no.5
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• pp.759-764
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• 2012

In this paper, we propose a microwave hyperthermic lipolysis method to reduce subcutaneous fat without skin burn using external RF antenna. Since skin is closer to the antenna and has higher conductivity compared to the fat beneath, the temperature of the skin rises higher than that of the fat when the external antenna illuminates EM energy into a body, which may cause skin burn. In order to avoid the damages on skin, a skin cooling system is employed to the external antenna. The operating frequency is set at 5.8 GHz which is one of the ISM bands, to concentrate EM power efficiently on fat and not to heat up the muscle behind the fat. The operation time and RF power level has been determined based on experimental results with pork. The feasibility of the proposed method was shown by applying the method to the rat.

• Journal of computational fluids engineering
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• v.6 no.1
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• pp.1-13
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• 2001

The natural convection heat transfer and solidification in a stratified pool are studied. The flow and heat transfer characteristics in a heat generating pool are compared between single-layered and double-layered pools. And local Nusselt number distributions on outer walls are obtained to consider thermal loads on a vessel wall. The cooling and solidification of Al₂O₃/Fe melt in a hemispherical vessel are simulated to study the mechanism of heat transfer and temperature distribution. A unstructured mesh is chosen for this study because of the non-orthogonality originated from the boundaries of double-layered pool. Interface between the layers is modeled to be fixed. With this assumption mass flux across the interface is neglected, but shear force and heat flux are considered by boundary conditions. The colocated cell-centered finite volume method is used with the Rhie-Chow interpolation to compute cell face velocity. To prevent non-physical solutions near walls in case body force is large the wall pressure is extrapolated by the way to include body force. The numerical solutions calculated by current method show that averaged downward heat flux of the double-layered pool increases compared to single-layered pool and maximum temperature occurs right below the interface of the layers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.3
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• pp.39-48
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• 1989

The concrete temperature in mass concrete rises rapidly above the placing temperature owing to the heat given off by the hydrating cement. This temperature rise produces tensile stress and cracks which later become the cause of water leakage in concrete structures. It is essential, therefore, to reduce the interior heat of concrete dam given off by hydrating cement by artificial cooling. The present study aiming to study the temperature variations in mass concrete by pipe cooling, compars the actual measurements of Chungju Dam with the temperature calculated by Finite Difference Method(FDM), and it found that the results closely agree with each other. Based on these results, the analyses are performed simulate the interior temperature history of concerte dam made of type II (moderate heat) portland cement under various coditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.484-487
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• 2002

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss. In this paper, the proto type mold transformer of 50kVA class is investigated by routine, type, special test. The outdoor energized aging test is investigated by back-to-back method to verify the long time performance of pole mold transformer. The aging process of transformer is analyzed by various diagnosis method such as DC voltage-current test, $tan{\delta}$, Meggar measurement, winding temperature and etc.

• Acute and Critical Care
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• v.33 no.4
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• pp.246-251
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• 2018

Background: Target temperature management (TTM) improves neurological outcomes for comatose survivors of out-of-hospital cardiac arrest. We compared the efficacy and safety of a gel pad cooling device (GP) and a water blanket (WB) during TTM. Methods: We performed a retrospective analysis in a single hospital, wherein we measured the time to target temperature ($<34^{\circ}C$) after initiation of cooling to evaluate the effectiveness of the cooling method. The temperature farthest from $33^{\circ}C$ was selected every hour during maintenance. Generalized estimation equation analysis was used to compare the absolute temperature differences from $33^{\circ}C$ during the maintenance period. If the selected temperature was not between $32^{\circ}C$ and $34^{\circ}C$, the hour was considered a deviation from the target. We compared the deviation rates during hypothermia maintenance to evaluate the safety of the different methods. Results: A GP was used for 23 patients among of 53 patients, and a WB was used for the remaining. There was no difference in baseline temperature at the start of cooling between the two patient groups (GP, $35.7^{\circ}C$ vs. WB, $35.6^{\circ}C$; P=0.741). The time to target temperature (134.2 minutes vs. 233.4 minutes, P=0.056) was shorter in the GP patient group. Deviation from maintenance temperature (2.0% vs. 23.7%, P<0.001) occurred significantly more frequently in the WB group. The mean absolute temperature difference from $33^{\circ}C$ during the maintenance period was $0.19^{\circ}C$ (95% confidence interval [CI], $0.17^{\circ}C$ to $0.21^{\circ}C$) in the GP group and $0.76^{\circ}C$ (95% CI, $0.71^{\circ}C$ to $0.80^{\circ}C$) in the WB group. GP significantly decreased this difference by $0.59^{\circ}C$ (95% CI, $0.44^{\circ}C$ to $0.75^{\circ}C$; P<0.001). Conclusions: The GP was superior to the WB for strict temperature control during TTM.

• Journal of the Korean Society of Safety
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• v.17 no.1
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• pp.72-78
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• 2002

Among the disposal techniques of inorganic wastewater sludges from industries most of sludges were dealed with buring underground inefficiently. But we have tried to recycle the resources that exhausted inorganic sludges were properly blended to certain ratioes to make lightweight aggregate, that means manufacturing of it can be possible through blending of various components, drying, sintering, cooling and crushing to certain sizes that are needed by consumers. As disposal method of inorganic wastewater sludge is changed to environmentally fraternative method, this method could be very useful to make lightweight aggregates for decoration of building and the other so many purposes of those usages. That could be economically useful due to expected income for buring costs of ordinary disposal method form industries and sales income after manufacturing it. The second important profit is saving foreign currency from purchasing self-developed lightweight aggregate insteas of importing expensive foreign product. This product will be also very impressive to user because of the fraternative lightweight to be composed of apatite structure that is important part of human body.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.10a
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• pp.151-152
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• 2008

PCM has the ability to change their state, these materials absorb energy during the heating process as a body contact and release energy during a reverse cooling process as phase change take place. Using the thermal energy storage of PCM which has a melting point 15 to $35^{circ}C$ is one of the most effective ideas for utilization in textile finish. In this study, microencapsulated PCM(MCPCM) were synthesized by sol-gel method using the octadecane(or nonadecane) as PCM and the silica as microcapsule materials. To develop smart temperature adaptable textile, coating process was applied to textile substrate using a composition included MCPCM.