• Progress in Superconductivity and Cryogenics
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• v.5 no.2
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• pp.16-19
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• 2003

Quench and recovery process of high-temperature-superconductor (HTS) film deposited on the sapphire substrate is studied numerically. The quench is developed by fault current and the superconductivity is recovered by convection of heat into coolant. After the fault current. the HTS film experiences the quench state. current sharing state. and finally recovers the superconductivity. Numerical results of this study are compared to the previous experimental results. and shows that this numerical work can explain the mechanism of quench/recovery characteristics of HTS film.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.181-184
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• 2003

Quench and recovery process of high-temperature -superconductor (HTS) film deposited on the sapphire substrate is studied numerically. The quench is developed by fault current and the superconductivity is recovered by convection of heat into coolant. After the fault current, the HTS film experiences the quench state, current sharing state, and finally recovers the superconductivity. Numerical results of this study are compared to the previous experimental results, and shows that this numerical work can explain the mechanism of quench/recovery characteristics of HTS film.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.280-285
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• 2012

This study was conducted to establish proper milling condition and harvesting time for improving the milling recovery of head foxtail millet grain. Brown foxtail millet recovery and the percentage of head foxtail millet recovery were significantly different according to the number of hulling and milling time. Also, the interaction of these factors had influence on brown foxtail millet recovery and the percentage of head foxtail millet recovery. To improve the percentage of head foxtail millet recovery, it was effective to hull grain twice and mill for 1.30 minute. 1000-grain weight of brown foxtail millet, brown foxtail millet recovery, hardness of brown foxtail millet, milling recovery, and the percentage of milling recovery of head foxtail millet grain were significantly different according to harvesting day after heading. For improving the ratio of ripened grain and the percentage of recovery of head foxtail millet, it is recommended to harvest 45 days (accumulated temperature : $1,148^{\circ}C$) after heading (DAH) in early maturing Hwangkeumjo, 50 DAH (accumulated temperature : $1,150^{\circ}C$) in mid-late maturing Samdamae and Kyeongkwan1, and 55 DAH (accumulated temperature : $1,168^{\circ}C$) in late maturing Samdachal.

• Computers and Concrete
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• v.24 no.3
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• pp.249-258
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• 2019

In order to investigate the strength recovery of fire-damaged concrete after post-fire curing, concrete specimens were heating at $2^{\circ}C/min$ or $5^{\circ}C/min$ to 400, 600 and $800^{\circ}C$, and these exposed specimens were soaked in the water for 24 hours and following by 29-day post-fire curing. The compressive strength and split tensile strength of the high-temperature-exposed specimens before and after post-fire curing were tested. The proportion of split aggregate in the split surfaces was analyzed to evaluate the mortar-aggregate interfacial strength. After the post-fire curing process, the split tensile strength of specimens exposed to all temperatures was recovered significantly, while the recovery of compressive strength was only obvious within the specimens exposed to $600^{\circ}C$. The tensile strength is more sensitive to the mortar-aggregate interfacial cracks, which caused that the split tensile strength decreased more after high-temperature exposure and recovery more after post-fire curing than the compressive strength. The mortar-aggregate interfacial strength also showed remarkable recovery after post-fire curing, and it contributed to the recovery of split tensile strength.

• Journal of the Korean Home Economics Association
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• v.39 no.5
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• pp.39-47
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• 2001

The purpose of this study was to investigate two different kinds of t-shirts on thermal responses at air temperature of $23{\pm}2^{\circ}C$, relative humidity of $70{\pm}5%$ and wind velocity not more than 0.5 m/sec. Five healthy men wearing boxy type t-shirts or fitted type t-shirts, participated as the subjects. Rectal temperature, skin temperatures, heart rate, clothing microclimate and subjective sensation were measured every 2 minute during experiment(rest, walking, recovery each 20 min.) and compared between two experimental garments(boxy type and fitted type t-shirts). Rectal temperature was lower in recovery phase at wearing fitted type t-shirts. Chest skin temperature was higher at wearing fitted type t-shirts and thigh and leg skin temperature were higher at wearing boxy type t-shirts.

• Progress in Superconductivity and Cryogenics
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• v.21 no.3
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• pp.1-5
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• 2019

The superconductor stability theories are consistently described by the integral formula. If the defined stability function is a simple decreasing function, it becomes a cryogenic stability condition. If the stability function has a maximum value and a minimum value, and the maximum value is less than 0, then it is a cold-end recovery condition. If the maximum value is more than 0, it can be shown that the unstable equilibrium temperature, that is, the MPZ (minimum propagation zone) temperature distribution can exist. The MPZ region is divided into two regions according to the current ratio. At the low current ratio, the maximum dimensionless temperature is greater than 1, and at the relatively high current ratio, the maximum dimensionless temperature is less than 1. In order to predict the minimum quench energy, the dimensionless energy was obtained for the MPZ temperature distribution. In particular, it was shown that the dimensionless energy can be obtained even when the MPZ maximum temperature is 1 or more.

• Journal of Aquaculture
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• v.10 no.3
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• pp.281-288
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• 1997

We investigated the optimal concentratin of ethyl-p-aminobenzoate for the exfoliation and recovery of young abalone, Haliotis discus hannai in according to different water temperatures, for the purpose of preventing the damage of shell and muscle to ecfoliated from shelter. In the 14$^{\circ}C$ water temperature, young abalones were exfoliated after 16, 35, 35 and 35 minutes in 150, 100, 75 and 50ppm concentration of ethyl-p-aminobenzoate, and were recovered after 100, 60, 30 and 30 minutes, respectively. Exfoliation rate of abalone were 100% except for 50 ppm (80%) and recovery rate were 100% of all concentration. In the $18^{\circ}C$ water temperature, young abalones were exfoliated after 4, 4, 6, 8, 8 and 12 munutes in 300, 200, 150, 100, 75 and 50ppm concentration of ethyl-p-aminobenzoate, and were recovered after 210, 180, 90, 60, 30, 20 and 20 minutes, respectively. Exfoliation rate of abalone were 100%, and recovery rate were 100% except for 200 and 300ppm (90%). In the $24^{\circ}C$ water temperature, young abalones were exfoliated after 8, 10, 10 and 12 minutes in 150, 100, 75 and 50ppm concentration of ethyl-p-aminobenzoate, and were recovered after 70, 50, 30 and 20 minutes, respectively. Exfoliation and recovery rate of abalone were 100%. In the 18$^{\circ}C$water temperature, exfoliation rate that treated with freshwater during 20 minute were 80, 50, 30 and 5% in 100, 75, 50 and 25% of fresh water, and recovery after 60, 15, 10 and 2 minutes, respectively and recovery arate were 100% except of r 100% freshwater. In this study, we suggest the reslults that the exfoliation and recovery by ethly-p-aminobenzoate were more effected in $18^{\circ}C\;and\;24^{\circ}C$ of sea water temperature than those of $14^{\circ}C$. The optimal concentration of ethyl-p-aminobenzoate was 50ppm at those water temperature. We raised 20 individual of young abalones at water temperature of $16^{\circ}C$ in the 1$\ell$ o ftnk and checked the variatin of dissolved oxygen (DO) by respiration of abalones that treated with 75ppm of ethyl-p-aminobenzoate. Before anesthetizion, DO were 6.17~6.20mg/$\ell$ and slowly decreased. But after 60 minutes, DO decreasing were stopped in 5.42~5.46mg/$\ell$. On the other hand, the control was continuously decreased and 5.27mg/$\ell$ after 60 minutes. The heartbeats of abalones were 33~45/minute in the water temperature of $18^{\circ}C$, but that treated with 100 ppm concentration of ethyl-p-aminobenzoate during 60 minutes, was 0/minute. And heartbeats of recovered abalones from anesthetizion were 29~43/minute.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.1
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• pp.64-70
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• 2015

Organic Rankine cycle (ORC) is an useful cycle for power generation system with low temperature heat sources ($80{\sim}400^{\circ}C$). Since the boiling point of operating fluid is low, the system is used to recover the low temperature heat source of waste heat energy. In this study, a ORC with R134a is applied to recover the waste energy of condenser of coal fired power plant. A system model is developed via Thermolib$^{(R)}$ under Simulink/MATLAB environment. The model is composed of a refrigerant heat exchanger for heat recovery from coal fired condenser, a drum, turbine, heat exchanger for ORC heat rejection, storage tank, water recirculation pump and water drip pump. System analysis parameters were heat recovery capacity, type of refrigerants, and types of turbines. The simulation model is used to analyze the heat recovery capacity of ORC power system. As a result, increasing the overall heat transfer coefficient to become the largest of turbine power is the most economical.

• Journal of the Korean Solar Energy Society
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• v.35 no.5
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• pp.57-65
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• 2015

The Potential Induced Degradation(PID) in PV module mainly affected by various performance conditions such as a potential difference between solar cell and frame, ambient temperature and relative humidity. The positive charges as sodium ions in front glass reach solar cell in module by a potential difference and are accumulated in the solar cell. The ions accelerate the recombination of generation electrons within solar cell under illumination, which reduces the entire output of module. Recently, it was generally known that PID generation is suppressed by controlling the thickness of SiNx AR coating layer on solar cell or using Sodium-free glass and high resistivity encapsulant. However, recovery effects for module with PID are required, because those methods permanently prevent generating PID of module. PID recovery method that voltage reversely applies between solar cell and frame contract to PID generation begins to receive attention. In this paper, PID recovery tests by using voltage under various outdoor conditions as humidity, temperature, voltage are conducted to effectively mitigate PID in module. We confirm that this recovery method perfectly eliminates PID of solar cell according to repeative PID generation and recovery as well as the applied voltage of three factors mainly affect PID recovery.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.10
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• pp.705-710
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• 2012

This study aims to analyse changes of inner temperature of PVS(Passive ventilation skin) and heat recovery when it has ventilation of air through PVS using numerical simulation in the winter condition. Results are as follows. 1) In case of the air inflows through PVS, change of inner temperature of PVS is lower than in case of the air flows inner space to out space, by dynamic insulation. 2) It was identified that the temperature gradient of PVS were bigger by increases of ventilation amount. To reduce ventilation load, heat transfer efficiency at the inner side of PVS is important and what performance of insulation at the inner side of PVS secure helps to improve heat performance of all PVS.