• KOREAN JOURNAL OF CROP SCIENCE
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• v.10
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• pp.45-50
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• 1971

For the purpose of finding out the effect of heat treatment on biological response and mutation rate, rice seeds were heat treated before and after gamma irradiation. 1. At a dose of 20 KR, pre-irradiation heat treatment showed reduced biological damage and increased mutation rate as compared with non-heat treatment. 2. Mutation frequency was increased in post-treatment of heat shock than in pre-irradiation heat treatment and non-heat treatment. 3. Pre-irradiation heat treatment at 6$0^{\circ}C$ for 30 minutes markedly reduced the biological damage and increased the mutation rate. 4. Mutation spectrum in heat treatment was different from non-treatment.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.379-388
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• 2013

Diabetic nephropathy is one of the serious complications in patients with either type 1 or 2 diabetes mellitus but current treatments remain unsatisfactory. Results of clinical research studies demonstrate that Panax ginseng can help adjust blood pressure and reduce blood sugar and may be advantageous in the treatment of tuberculosis and kidney damage in people with diabetes. The heat-processing method to strengthen the efficacy of P. ginseng has been well-defined based on a long history of ethnopharmacological evidence. The protective effects of P. ginseng on pathological conditions and renal damage associated with diabetic nephropathy in the animal models were markedly improved by heat-processing. The concentrations of less-polar ginsenosides (20(S)-Rg3, 20(R)-Rg3, Rg5, and Rk1) and maltol in P. ginseng were significantly increased in a heat-processing temperature-dependent manner. Based on researches in animal models of diabetes, ginsenoside 20(S)-Rg3 and maltol were evaluated to have therapeutic potential against diabetic renal damage. These effects were achieved through the inhibition of inflammatory pathway activated by oxidative stress and advanced glycation endproducts. These findings indicate that ginsenoside 20(S)-Rg3 and maltol are important bioactive constituents of heat-processed ginseng in the control of pathological conditions associated with diabetic nephropathy.

• Journal of the Korea Safety Management & Science
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• v.26 no.3
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• pp.59-70
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• 2024

This study aims to estimate the scope of damage impact with a real-life explosion case and a damage prediction program (ALOHA) and suggest measures to reduce risk by comparing and analyzing the results using a Probit model. After applying it to the ALOHA program, the toxicity, overpressure, and radiant heat damage of 5 tons of storage scopes between 66 to 413 meters, and the real-life case also demonstrated that most of the damage took place within 300 meters of the LPG gas station. In the Probit analysis, the damages due to radiant heat were estimated as first-degree burns (13-50%), while structural damage (0-75%) and glass window breakage (94-100%) were expected from overpressure, depending on the storage volume. After comparing the real-life case and the damage prediction program, this study concluded that the ALOHA program could be used as the scope of damage impacts is nearly the same as the actual case; it also concluded that the analysis using the Probit model could reduce risks by applying calculated results and predicting the probability of human casualties and structural damages.

• Journal of Ocean Engineering and Technology
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• v.16 no.4
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• pp.48-53
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• 2002

Fiber-reinforced composites are extensively used in electronic, ship and aerospace applications due to their high strength and high toughess. In these applications, they are often subjected to localized heat damage due to various sources. In order to ensure their reliability, it is important to predict their residual properties using nondestructive evaluation thchniques. Fabric fiber composite specimens were manufactured with six layers of the glass-fiber prepreg and the carbon-fiber prepreg, respectively. The specimens were subjected to a localized heat damage using a heated copper tip with a diameter of 10mm at 35$0^{\circ}C$(CFRP) and 30$0^{\circ}C$(GFRP), respectively. The specimens were then subjected to tension tests while acoustic emission (AE) activities of specimens were collected. The AE activity of all specimens showed three types of distinct frequency regions. Those are matrix cracking, failure of the fiber/matrix interface and fiber breakage.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.8 no.2
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• pp.33-41
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• 2012

The component cooling water heat exchangers are critical components in a nuclear power plant. As the operation years of the heat exchanger go by, the maintenance costs required for continuous operation also increase. Most heat exchangers have carbon steel shells, tube support plates and flow baffles. The titanium tube is susceptible to flow induced vibration. The damage on carbon steel tube support rod and titanium tube around cooling water entrance area is inevitable. Therefore, analysis of internal flow around the component cooling water entrance and tube channel is a good opportunity to seek for failure prevention practice and maintenance method. The numerical study was carried out by FLUENT code to find out the causes of tube failure and its location.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.197-201
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• 2006

In the development process of a fuel-rich gas generator using kerosene and LOx for a 30 tonf class liquid rocket engine, a heat damage occurred at the LOx post of swirl coaxial injectors used in the gas generator and the problem has been examined. To prevent the heat damage, injectors are redesigned to have an increased recess while maintaining internal mixing, which minimizes recirculation region to prevent anchoring of the flame in the recirculation region. The combustion test results of the sub-scale gas generator showed that this scheme can prevent heat damage of the LOx post in the swirl coaxial injectors of the fuel-rich gas generator.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.5
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• pp.507-511
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• 2024

Various process modifications have been used to minimize SiO₂ gate oxide aging in metal-oxide-semiconductor field-effect transistors (MOSFETs). In particular, post-metallization annealing (PMA) with a deuterium ambient can effectively eliminate both bulk traps and interface traps in the gate oxide. However, even with the use of PMA, it remains difficult to prevent high levels of radiation-induced gate oxide damage such as total ionizing dose (TID) during long-term missions. In this context, additional low-temperature heat treatment (LTHT) is proposed to recover from radiation-induced damage. Positive traps in the damaged gate oxide can be neutralized using LTHT, thereby prolonging device reliability in harsh radioactive environments.

• Fashion & Textile Research Journal
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• v.10 no.3
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• pp.389-393
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• 2008

The purpose of this study is to provide beauticians with the fundamental material for them to use effectively heat permanent wave and satisfy their customers. It carried out an experiment with hair of a woman in her late twenties to investigate the change of physical and morphologic characteristics by its water content when performing heat permanent wave. It evaluated the water content as 0g, 1g, 2g, 3g and 4g respectively when performing the heat permanent wave on hair, then it compared and observed the wave type, tensile strength and elongation for its physical change also observed the morphologic change by scanning electronic microscope and transmission electronic microscope. The result of experiment on the physical specificity revealed that the wave was the most ideal when the water content was 2 g. The material with much water content made wave but the result was not satisfied. In the case of hair with water content of nearly 0g didn't make wave. In terms of tensile strength and elongation, the tensile strength was generally reduced as hair was damaged, on the contrary, the elongation was increased. It observed the change of morphologic characteristic and got the result that the damage on hair cuticle was deepen as its water content was decreased. It also showed the result that damage happened on hair cuticle more than hair cortex with the observation of fine structure on hair section by transmission electronic microscope. Generally chemical treatment damaged hair. Under consideration of this aspect, the ultimate goal of this thesis is to minimize the damage of hair caused by chemical treatment and get the satisfaction on the hair style. The result of experiment presented that the hair showed the best result when its water content was 2 g.

• Korean Security Journal
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• no.2
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• pp.83-98
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• 1999

The LPG station's explosion at Bucheon city was a major accident which with rare frequency of occurrence but large damage effect. Therefore, to prevent similar accident in the future from LPG chargings stations which located at inner urban area, it needs to identify the damage effects of such facilities by comparing theoretically quantities risks-PHAST. The BLEVE effects from the accident showed similar level in case of heat flux, however, the over pressure level reflected at reduced distance. The structure damage to the nearby area showed comparatively large reduction of concrete strength and shape changes through by heat effect while the overpressure effect was small.

• Laser Solutions
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• v.11 no.4
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• pp.13-20
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• 2008

The damage threshold measurement of gold films is carried out with ultrashort-pulse laser. An enhanced two temperature model is developed to encounter the limitation of linear modeling during ultrashort pulse laser ablation. In which the electron heat capacity is calculated using a quantum mechanical approach based on a Fermi-Dirac distribution, temperature-dependent electron thermal conductivity valid beyond the Fermi temperature is adopted, and reflectivity and absorption coefficient are estimated by applying a temperature-dependent electron relaxation time. The predicted damage threshold using the proposed enhanced modelclosely agreed with experimental results, demonstrating the importance of considering transient thermal and optical properties in the modeling of ultrashort pulse laser ablation.