• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.42 no.4
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• pp.259-266
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• 2006

In this study, the 2-way condensation system was designed applying air-to-air heat pump to dry a marine product such as squid in the winter. And to be made the drying apparatuses by this system, there are two kinds of type, A type, was set a compressor outside of the drying apparatus, B type, was set a compressor in the drying room. And then the variations of temperature in drying room were measured to compare the heating performance of the drying apparatuses between A type and B type at $-6.5^{\circ}C$, outdoor temperature. The temperature of the drying room for B type was increased to $36^{\circ}C$ but the temperature of the drying room for A type was not increased to $36^{\circ}C$, to be increased to $20^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1348-1350
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• 2010

Conidia of Beauveria bassiana ARSEF-7060, produced in millet amended with plant oils such as sunflower, corn, or cotton seed oil, were exposed to $45^{\circ}C$ of wet heat for 90 min. Conidia from millet+corn oil medium had the highest thermotolerance [$LT_{50}$ (median survival time): 45.7 min]. The mycotized millet grains were coated with each of the same plant oils as a granular formulation and subjected to $50^{\circ}C$ of dry heat for 8 h. Corn oil coating ($LT_{50}$: 8.68 h) was superior to sunflower and cotton seed oil coatings, suggesting the feasibility of using corn oil to increase conidial thermotolerance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.402-405
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• 2002

This paper presented the characteristic of Heat-transfer on the winding composed with Epoxy-resin in a 50 kVA cast-resin dry type transformer The resin cast transformer is used widely in supplying electricity systems. However, to know the thermal characteristics of that is very useful in designing, manufacturing, and maintaining, there is no pertinent method to calculate this. In this paper, Based on the results of the physical characteristics and the simulation by commercial software using FEM method, we established the Prototype Model for this. According to that Model, an analysis on a variation of the hottest spot temperature was discussed as a function of thermal conductivity for the individual windings composed with Epoxy-resin. The thermal conductivity of the individual windings with reference to upper way was discussed.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.7
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• pp.759-766
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• 1988

the effect of heat treatment in oxygen ambient on the nucleation and growth of oxidation induced stacking faults(OSF) in n-type(100)silicon wafer has been investigated. The growth of OSF is determind as a function of oxygen concentration in silicon wafer, heat treatment time and temperature, and the activation energy for the growth of OSF can be obtained from the growth kinetics. The activation energies are respectively 2.66 eV for dry oxidation and 2.37 eV for wet oxidation. In this paper, we have also studied the structural feature of OSF with the comparison of optical microscopic morphology and crystalline structure.

• Nuclear Engineering and Technology
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• v.38 no.6
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• pp.483-488
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• 2006

Highly radioactive waste is placed in metal canisters embedded in dense clay termed buffer. The radioactive decay is associated with heat production, which causes degradation of the buffer and thereby time-dependent loss of its waste-isolating potential. The buffer is prepared by compacting air-dry smectite clay powder and is initially not fully water saturated. The evolution of the buffer starts with slow wetting by uptake of water from the surrounding rock followed by a long period of exposure to heat, pressure from the rock and chemical reactants. It can be described by conceptual and theoretical models describing processes related to temperature (T), hydraulic (H), mechanical (M) and chemical performance (C). For temperatures below 90 C more than 75 % of the smectite will be preserved for 100 000 years but cementation may reduce the excellent performance of the buffer to a yet not known extention.

• Textile Coloration and Finishing
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• v.10 no.2
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• pp.45-54
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• 1998

This study surveys relation between thermal shrinkage and thermal stress properties after process simulation of heat treatment with various PET filament yarns. For this purpose, 12 kinds of regular yarns and POY, 6 kinds of DTY and 5 kinds of composite yarns were experimented for investigating step thermal shrinkage, total thermal shrinkage and total thermal stress and maximum thermal stress temperature. Thermal stress and shrinkage of the various specimens treated with wet and dry heats were analysed and discussed with the conditions of heat treatment. finally, relationship between thermal stress and shrinkage of the various PET filaments such as regular yarns, POY, DTY and composite yarns were investigated with the PET filament characteristics.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1997.10a
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• pp.114-121
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• 1997

회전 열파이프의 열전달 성능은 액막 두께 및 증발부로 귀환되는 응축 액막 유동율에 의해 결정된다. 그 동안 응축액 유동율을 촉진시키기 위하여 용기 내벽에 groove, 테이퍼 및 나선형 코일을 삽입하여 유동율을 높이는 방법들이 연구되었다. 본 연구도 회전 열파이프의 내부 관벽 구조에 관한 것으로써 삼각 단면을 갖는 회전 열파이프의 열전달 특성을 파악하고자 하였다. 삼각 단면을 갖는 회전 열파이프는 고속 회전 영역에서 모서리 부분으로 액막이 집중되어 관 내벽에 형성되는 액막 두께를 줄일 수 있으나 증발부에서 국부적인 과열이 발생되어 불안정한 작동 상태를 나타내었다. 따라서 본 연구에서는 개선방안으로 증발부에 부분적으로 원형관을 접합하였으며, 그 결과 dry-out의 억제와 함께 삼각 유동 단면에 의한 액막 두께 감소 효과를 볼 수 있었다. 회전체 발열부 냉각에 적용시키기 위해서는 앞으로 최적의 기하학적 형상에 따른 충전율 및 액막에서의 열전달에 대한 정량적인 해석 연구가 필요할 것으로 생각된다.

• KSTLE International Journal
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• v.3 no.1
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• pp.17-22
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• 2002

Roughing of tool steel in its hardened state represents a real challenge in the die and meld industry and process improvement depends on research of tool material, coating technique, and lubrication. However, roughing of hardened steels generates extreme heat and without coolant flooding, tool material cannot withstand the high temperature without choosing the right tools with proper coating. This research conducted milling tests using coated ball end mills to study effects of cutting conditions and geometric parameters of ball end mills on the machinability of hardened tool steel. KP4 steel and STD 11 heat treated steels were used in the dry cutting as the workpiece and TiAIN coated ball end mills with side relief angle of 12$^{\circ}$ was utilized in the cutting tests. Cutting forces, tool wear, and surface roughness were measured in the cutting tests. Results from the experiments showed that 85 m/min of cutting speed and 0.32 mm/rev of feed rate were optimum conditions for better surface finish during rough cutting and 0.26mm/rev with the same cutting speed are optimum conditions in the finish cutting.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.760-765
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• 2000

The study deals with the development of a computational procedure for evaluating the temperature rise in dry and lubricated multi-layered contacts of head/disk interface. A transient computational model with a transformed rectangular computational domain is utilized. A model and a computational method for micro-contact with sub-lubricated zone, including friction heat generation, have been presented. The model was applied, taking full account of the changes in contact area and contact load due to frictional heating. The computational distribution of temperature is obtained with the analytical findings for various composition and contact conditions. Especially, a rapid rise ($220^{\circ}C$ or above) in read head temperature lese to a saturation in the influence of a thermal spike on signal performance. This general class of problems can be treated provided that heat generation distribution and layer properties are known.

• Journal of Power System Engineering
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• v.11 no.4
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• pp.92-97
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• 2007

This study aims at investigating the wear behavior of thermally sprayed Ni-based self-flux alloy coatings against different counterparts. Ni-based self-flux alloy powders were flame-sprayed onto a carbon steel substrate and then heat-treated at temperature of $1000^{\circ}C$. Dry sliding wear tests were performed using the sliding speeds of 0.2 and 0.8 m/s and the applied loads of 5 and 20 N. AISI 52100, $Al_2O_3$, $Si_3N_4$ and $ZrO_2$ balls were used as counterpart materials. Wear behavior of Ni-based self-flux alloy coatings against different counterparts were studied using a scanning electron microscope(SEM) and energy dispersive X-ray spectroscopy (EDX). It was revealed that wear behavior of Ni-based self-flux alloy coatings were much influenced by counterpart materials.