• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3827-3831
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• 2014

This paper aims to solve the problem deterioration of power fuses. The deterioration of a power fuse is a cause of failure misoperation by a normal current flowing reduplicatively to fuse the element. An extension survey of a load feature rerating power fuse examined the power fuse deterioration removal, the cause of the deterioration of the power fuse, the front-after, and the thermal variation of the inside transformer room electric power equipment. The transformer showed an average improvement of $6[^{\circ}C]$. The temperature of the electrical line showed $7{\sim}8[^{\circ}C]$ improvement. The static condenser and direct reactor was $2{\sim}3[^{\circ}C]$ high-state maintenance the temperature and equipment syntonization relationship. In the subject of study $0.5{\sim}1.0[^{\circ}C]$ stabilizing three phase power fuse temperature differential was. Suggestion in the transformer room environment power equipment between the cause temperature happen elimination to deterioration of power fuse and temperature rise control.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.565-572
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• 2009

Deterioration of the outdoor thermal environment in urban areas such as heat island has become worse due to urbanization and overpopulation, etc. In this study, a new method which is coupled simulation of convection and radiation to evaluate outdoor thermal environment in urban area will be proposed. Because the solar radiation affects on outdoor thermal environment massively, therefore the radiation calculation is very important in outdoor thermal environment prediction. The coupled simulation proposed in this study can assess the outdoor thermal environment with accurate.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.1
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• pp.190-196
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• 2006

In the existed study, a fire outbreak in a reinforced concrete structure looses the organism by the different contraction and expansion of hardened cement pastes and aggregate, and causes cracks by thermal stress, leading to the deterioration of the durability. So accurate diagnosis of deterioration is needed based on mechanism of fire deterioration in general concrete structures. Fundamental information and data on the Properties of concrete exposed to high temperature are necessary for accurate diagnosis of deterioration. Therefore, This study is willing to propose fundamental data for quick and accurate diagnosis of deteriorated concrete structure by fire damage with making variable concrete test specimen, exposing high temperature environment, observing the explosive spalling and examining engineering property.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.193-197
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• 2001

The growth in concrete structures repair has prompted major efforts to develop high early strength concrete. The internal or external restraint of thermal shrinkage movements could thus generate tensile stresses in concrete structures if it is used rapid setting repair concrete. Restrained shrinkage and thermal stresses could produce microcracks in concrete which increase its permeability and accelerate its long-term deterioration under weathering and load effects. This study aims at evaluation and increase of the engineering properties of high early strength concrete using regulated set cement.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.96-97
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• 2013

Research and analysis on thermal insulation status of existing buildings are needed to make data for repair and rehabilitation caused by deterioration in insulating material performance. To do this, we have researched and analyzed the insulation status of existing buildings according to the balcony with measuring instruments in pre-set investigation conditions.

• Journal of the Korea Society of Computer and Information
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• v.22 no.10
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• pp.19-26
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• 2017

In this paper, we propose an efficient image equipment implementation for the detector characteristics of various detectors by analyzing un-cooled thermal detector that exhibits nonlinear changes due to external temperature effects. First, we explain Thermal Electric Cooler for un-cooled detector temperature control system and Non-image correction methode for IR system. Second, we present the results of a study on an efficient control technique that can minimize the deterioration of image quality by controlling a un-cooled thermal detector without a thermal electric cooler(TEC) inside. Third, we suggest Image Correction Methods for Uncooled IR TECless Detector with Non-linear characteristics due to Temperature Change. So, we analyze and present the results of Image correction methods for various un-cooled thermal detector.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.289-292
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• 2007

To prevent the damage of glass lens molds and deterioration of glass lenses using in progressive GMP process, a thermal stress and a deformation of the glass lens molds at forming temperature should be considered in the design step. In this study, as a fundamental study to develop a multi cavity mold used in an aspheric glass lens molding, a heat transfer and a thermal stress analysis were carried out for the case of one cavity glass lens mold used in progressive GMP process. Finally, using analysis results, we estimated the thermal stress in a glass lens mold and predicted a modified height of guide ring that determines the forming height of a glass lens.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.606-610
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• 2003

The 200 class insulation system which adopted to traction motor have excellent dielectric strength but weaken to thermal stress therefore deterioration phenomena analysis according to thermal stress is necessary. Accelerated thermal aging tests have been used to determine thermal reliability of stator coils used as traction motor in electric multiple unit. The conventional aging test is carried on according to IEC 60034-18-31 and IEEE Std. 275-1992. Variation in insulation resistance, P.I, capacitance, dielectric loss($tan{\delta}$) and partial discharge are measured during the aging cycle. Sample coils for traction motor were tested by accelerated aging test which composed of heat, vibration and moisture. Reliability and expected life were evaluated on the insulation system for traction motor.

• Journal of the Korean Solar Energy Society
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• v.29 no.6
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• pp.45-55
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• 2009

Deterioration of the outdoor thermal environment in urban areas has become worse and worse due to the urbanization and overpopulation, etc. Most of existing researches about thermal environment are focused on the indoor environment in which the radiation heat exchange is relatively constant. However, the outdoor thermal environment is changed with time passages, because the thermal environment is highly effected by solar radiation. Thus, to simulate the outdoor thermal environment with accuracy, the solar radiation calculation should be considered, and the radiation heat exchange between building surface and ground surface should be calculated. The purpose of this study is to develop the simulator that can be possible to evaluate the outdoor thermal environment and pedestrian thermal comfort. In this paper, a new method which is coupled with convective heat transfer simulation and radiative heat transfer simulation will be proposed. And the coupled simulation method will be described through case study for outdoor thermal environment. From the results of simulation, the coupled simulation proposed in this study can assess the outdoor thermal environment with accuracy.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.23-27
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• 2003

The effects of temperature and pH on color deterioration of anthocyanin in Schizandra fruit (Schizandra chinensis fructus) were determined with temperature range of $80{\sim}100^{\circ}C$ and pH range of $2.0{\sim}5.0$. Browning index was used as an index of color deterioration of crude anthocyanin extract from Schizandra fruit. As pH of crude anthocyanin extract was increased, color deterioration was accelerated, showing pH-dependency of thermal stability of anthocyanin extract from Schizandra fruit. Anthocyanin degradation could be modeled as a second-order rate reaction, with rate of $3.2{\times}10^{-3}\;h^{-1}\;(pH\;2.0){\sim}4.1{\times}10^{-3}\;h^{-1}\;(pH\;5.0)\;at\;100^{\circ}C$. Temperature dependence of deterioration was described by the Arrhenius relationship. Activation energies for pH $2.0{\sim}5.0$ ranged from $24.87{\sim}42.54\;kJ/mol^{-1}$.