• Fashion & Textile Research Journal
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• v.9 no.3
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• pp.347-350
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• 2007

To analyse basic properties for making packing batt according to doubling condition, packing batt yarn, of $300^D$, $900^D$, $3600^D$ made from DTY yarn $150^D$/48 were produced from KTDI. The results are as follows: The birefringence of the sample yarn increased with increasing the annealing temperature and denier. The initial modulus of the sample yarn decreased with increasing the annealing temperature and denier. The higher than annealing temperature of $160^{\circ}C$, initial modulus of the sample are equilibrated. The strain recovery ratio of samples decreased with increasing the annealing temperature and denier. The lower than annealing temperature of $140^{\circ}C$, strain recovery ratio of the sample are decreased Where the $900^D$, $3600^D$ yarns are at $100^{\circ}C$ the specific bending rigidity value obtained is 0.65kgf/d but the twisted yarn (3,600) obtained 0.006 ($gfcm^2/tex^2$). However, where the heat temperature is $160^{\circ}C$, specific bending rigidity value obtained 0.003($gfcm^2/tex^2$).

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.553-556
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• 2009

This research aims at the recovery of valuable resource and more efficient waste treatment through solving the problem of pyrolysis technique. At first, in order to raise the economical efficiency, the low temperature pyrolysis experiment was carried out at the temperature of $450^{\circ}C$, which is lower than the common pyrolysis temperature area ($500{\sim}1000^{\circ}C$). We could lower the reaction temperature and reduce the reaction time by using catalyst. Also we used indirect heat for the purpose of maintaining favorable anoxic condition. As a result, we could raise the recovery rate of the valuable copper and synthetic fuel oil. Furthermore, the by-products and flue gas could be treated more effectively as well. The flue gas passed through two stage neutralization tank, so that dioxin hardly occurs and other environment items are controlled fairly well to the environmental standard. Throughout this study, we produced the low temperature pyrolysis equipment (GTPK-001) as mentioned above, and we found out that the technique can be commercialized economically as well as environmentally friendly.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.4
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• pp.495-502
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• 2014

Fast recovery diodes (FRDs) were developed using the $p^{{+}{+}}/n^-/n^{{+}{+}}$ epitaxial layers grown by low temperature epitaxy technology. We investigated the effect of electrostatic discharge (ESD) stresses on their electrical and switching properties using current-voltage (I-V) and reverse recovery time analyses. The FRDs presented a high breakdown voltage, >450 V, and a low reverse leakage current, < $10^{-9}$ A. From the temperature dependence of thermal activation energy, the reverse leakage current was dominated by thermal generation-recombination and diffusion, respectively, at low and high temperature regions. By virtue of the abrupt junction and the Pt drive-in for the controlling of carrier lifetime, the soft reverse recovery behavior could be obtained along with a well-controlled reverse recovery time of 21.12 ns. The FRDs exhibited excellent ESD robustness with negligible degradations in the I-V and the reverse recovery characteristics up to ${\pm}5.5$ kV of HBM and ${\pm}3.5$ kV of IEC61000-4-2 shocks. Likewise, transmission line pulse (TLP) analysis reveals that the FRDs can handle the maximum peak pulse current, $I_{pp,max}$, up to 30 A in the forward mode and down to - 24 A in the reverse mode. The robust ESD property can improve the long term reliability of various power applications such as automobile and switching mode power supply.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.18-21
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• 2003

The effect of interface bonding strength on the recovery force of SMA wire reinforced polymer matrix composites was investigated by pullout test. Firstly, the recovery forces and transformation temperatures of various prestrained SMA wires were measured and 5% prestrained SMA wires were prepared for the reinforcements of composites. EPDM incorporated with 20vol% silicon carbide particles(SiCp) of 6, 12, $60{mutextrm{m}}$ size were used as matrix. Pullout test results showed that the interface bonding strength increased when the SiCp size decreased due to the increase of elastic modulus of matrix. Cyclic test of composites was performed through control of DC current at the constant displacement mode. The abrupt decrease of recovery force during cycle test at high current was occurred by thermal degradation of matrix. This was in good agreement with temperature related in the thermal degradation of matrix. The hysteresis of recovery force with respect to the temperature was compared between wire and composite and the hysterisis of composites was smaller than the wire due to less thermal conduction.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.7
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• pp.329-334
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• 2014

This study indicated the possibility of energy regeneration from waste coolant heat, by using thermoelectric generation integrated with heat pipe. The internal combustion engine rejects more than 60% wasteful energy to the atmosphere by heat. The thermoelectric generator has recently been studied, to convert the energy from engine waste heat into electricity. For coolant waste heat recovery, a thermoelectric generator was investigated, to find out the possibility of vehicular application. Performance characteristics were conducted with various test conditions of coolant temperature, coolant mass flow rate, air temperature, and air velocity, with the thermoelectric generator installed either horizontally or vertically. Experimental results show that the electric power and conversion efficiency increases according to the temperature difference between the hot and cold side of the thermoelectric generator, and the coolant flow rate of the hot side heat exchanger. Performance improvement can be expected by optimizing the heat pipe design.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.245-250
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• 2003

In order to control indoor air quality and save energy, it is needed to install a suitable ventilation system equipped with heat exchanger for heat recovery. The purpose of this research is to find the performance of paper heat exchanger for exhaust heat recovery, which exchanges latent heat as well as sensible heat. Experimental apparatus comprises heat exchanger model, constant temperature and humidity chamber, fan and measurement systems for temperature, pressure and flow rate. Thermal performance and pressure loss of the paper heat exchanger are measured and compared at various air velocities and outdoor conditions. Experimental results show that paper heat exchanger can recover $50{\sim}70%$ of the enthalpy difference between supply and exhaust air.

• Transactions of Materials Processing
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• v.5 no.4
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• pp.327-336
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• 1996

The effect of dynamic strain aging on high temperature deformation behaviour of the A-Mg alloy was investigated by strain rate change tests and stress relaxation tests between 20$0^{\circ}C$and 50$0^{\circ}C$. Yield point, short stress transient and periodic discontinuities on the stress-strain curve were considered as an evidence of the effect of dynamic strain aging. With this criterion two distinct strain rate-temperature regimes could be manifested. Dynamic strain aging was considered to be effective in the high temperature-low strain rate regime, whereas dynamic recovery was a dominant deformation mechanism in the low temperature-high strain rate regime. It was found that dynamic strain aging in the high temperature deformation was governed by the mechcanism of diffusion-controlled, viscous dislocation movement.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.2
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• pp.39-45
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• 2008

Objective : Skin barrier protects skin against harmful environment. Its function includes antimicrobial barrier as well as physical barrier. But there are few studies about the factors which improve skin barrier recovery after injury. The aim of this study is to investigate the factors which improve skin barrier recovery. Method : Nine hairless mice was anesthetized by inhalation and we tape stripped them. We used thermometer to know temperature one day ago, before anesthesia, before tape stripping, and after tape stripping. Vapometer was used to know transepidermal water loss before tape stripping, after tape stripping. And we used doppler flowmeter to measure blood flow before tape stripping, after tape stripping. Result : After analyzed data, we concluded that temperature was lower after anesthesia than before anesthesia and after tape stripping than before tape stripping. We could know that transepidermal water loss was lower after tape stripping than before tape stripping and more blood flowed after tape stripping. Conclusion : In our study, it was observed that temperature, transepidermal water loss, blood flow changed after tape stripping. But we thought lowered temperature was pathologic situation, more blood flow was to recover after injury. In traditional korean medicine, cold(寒) and imbalance of blood flow(血行) don't only make many skin diseases, but cold(寒) also obstructs blood flow. So we need to study how to warm cold(寒) and improve blood flow.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.11
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• pp.1044-1050
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• 2004

The present study has been conducted to develop a heat pipe heat exchanger for middle-high temperature ranged from 300 to $600^{\circ}C$. Heat transfer rate, overall heat transfer coefficient and temperature effectiveness were investigated using a heat pipe heat exchanger with Dowtherm A as working fluid. Theoretical analysis was also conducted, and the followings were obtained: (1) Heat exchange rate increased as waste gas temperature supplied to evaporator and frontal velocity in condenser increased, (2) Overall heat transfer coefficient increased by $3{\sim}7\%$ as frontal velocity in evaporator and condenser increased, (3) Temperature effectiveness was about $30\%$ in evaporator and was about $40\%$ in condenser, (4) Heat recovery rate was about $38\%$, (5) Pressure drop did not exceed $8\;mmH_{2}O$ under the running condition of $1{\sim}3Nm/s$, (6) Simulation results were corresponded with experimental results.

• Korean Journal of Ichthyology
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• v.31 no.4
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• pp.235-240
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• 2019

The anaesthetic effect of tricaine methanesulfonate (MS-222) concentrations and water temperatures for longtooth grouper (Epinephelus moara) and hybrid grouper (E. moara ♀ × E. lanceolatus ♂) were investigated. Anesthetic induction and recovery time were measured at 18, 22, 26 and 30℃ of Cwater temperature and 100, 150, 200 and 250 ppm of anesthetic concentrations. Anesthetic induction time tended to decrease with increasing concentration and water temperature. Recovery time was proportional to concentration, but inversely proportional to water temperature. However, there was no significant differences in recovery time at 22℃ or lower. The optimal anesthesia condition was 30℃ and 100 ppm, which was the shortest recovery time for longtooth grouper, and 150 ppm at 30℃ in the case of hybrid grouper because anesthetic time is significantly different with 100 ppm in spite of no significant differences with 100 ppm for recovery time. As a results of two-way ANOVA test, there was a significant difference between the species of longtooth and hybrid grouper. On the other hand, there was no interaction effect between concentration and species. Also, there was no interaction effect among species, concentration, and water temperature.