• Journal of the Korean Society of Safety
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• v.31 no.2
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• pp.119-126
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• 2016

Across the world, the industrialization has increased the frequency of climate anomaly. The size of damage due to recent natural disasters is growing large and fast, and the human damage and economic loss due to disasters are consistently increasing. Urbanization has a structure vulnerable to natural disasters. Therefore, in order to reduce damage from natural disasters, both hardware and software approaches should be utilized. Currently, however, the development of a statistical access process for 'analysis of disaster occurrence factor' and 'prediction of damage costs' for disaster prevention and overall disaster management is inadequate. In case of local governments, overall disaster management system is not established, or even if it is established, unscientific classification system and management lead to low utility of natural statistics of disaster year book. Therefore, in order to minimize disaster damage and for rational disaster management, the disaster damage survey process should be improved. This study selected gale as the focused analysis target among natural disasters recorded in disaster year book such as storm, torrential rain, gale, high seas, and heavy snow, and analyzed disaster survey process. Based on disaster year book, the gale damage size was analyzed and the issues occurring from the correlation of gale and damage amount were examined, so as to suggest an improvement plan for reliable natural disaster information collection and systematic natural disaster damage survey.

• Korean Journal of Human Ecology
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• v.14 no.3
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• pp.433-439
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• 2005

In this study, we investigated the morphological and physical changes of hair after bleaching treatments with different concentration of hydrogen peroxide in bleaching agent (3, 6, 9, or 12%) and various treatment time (10, 30, or 60 minutes). Tresses of virgin black hair were bleached using a commercial ammonium persulfate-hydrogen peroxide solution. The tensile strength of virgin hair treated with a bleaching agent depended on the concentration of hydrogen peroxide and the treatment time. As the concentration of hydrogen peroxide in bleaching agent went high and the treatment time increased, the tensile strength of the hair increased but the extension degree decreased. The virgin hairs which were not treated by bleaching agent showed morphologically healthy cuticle, whereas the bleached hairs showed swelled and damaged cuticle patterns. The swelling of the hair and the breaks of the cuticles increased positively by the concentration of hydrogen peroxide and the treatment time. These results suggest that exposure to more concentrated hydrogen peroxide with other bleaching components may lead to more severe hair damage.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.3
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• pp.76-82
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• 2010

A laborer always watched a process of production carefully but defective manufactures were inspected after press process. These inspections made a waste of human power and defective manufactures could make a serious damage of press mold. Therefore, AE(Acoustic Emission) system was introduced to prevention of the damage of the press molds, to a real time detection of defective manufactures and to save human power. AE system was introduced to solve this problem which is a detecting defective manufacture on real time and to prevent the damage of the press mold. In this research we get acoustic emission signal in accordance with weight and processing method of press by using AE sensor, Preamplifier, AE board signal board which occurs press processing and it analyzed various signal through using CMD8 software on the time. From the result, we found that the intensity and shape of the signal were changed according to the weight and processing type of the press. By using this special algorithm, it can judge the acoustic signal which occurs from press on real time.

• Advances in Traditional Medicine
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• v.7 no.1
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• pp.65-73
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• 2007

Water and alcohol extracts were prepared from dried and powdered leaves of Thuja orientalis (T. orientalis). The reducing power, total phenolic content, the 1,1-diphenyl-2-picrylhydrazyl scavenging activity, inhibitory effect on Fe (II)-EDTA-$H_{2}O_{2}$ (Fenton reaction system) induced DNA damage and inhibitory effect on human red blood cell (RBC) hemolysis were evaluated in the present study. At a concentration of 200 mg, water and alcohol extracts of T. orientalis inhibited the hydrolysis of DNA by 72.859% and 65.312%, respectively. Water and alcohol extracts of T. orientalis also inhibited 2,2'-Azobis(2-amidinopropane) dihydrochloride induced RBC hemolysis to the extent of 69.30% and 54.55%, respectively. The reducing power and antioxidative activity of water extract was found to be more than that of alcohol extract. This is attributable to the presence of higher amount of phenolic compounds in water extract. The present results indicate that the T. orientalis extracts are rich sources of natural antioxidants and can protect DNA and human red blood cells against free radical induced oxidative damage.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.128-128
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• 2010

In this study, we investigated the evolution and reduction of the surface roughness during the high-speed chemical dry thinning process of Si wafers. The direct injection of NO gas into the reactor during the supply of F radicals from NF3 remote plasmas was very effective in increasing the Si thinning rate, due to the NO-induced enhancement of the surface reaction, but resulted in the significant roughening of the thinned Si surface. However, the direct addition of Ar and N2 gas, together with NO gas, decreased the root mean square (RMS) surface roughness of the thinned Si wafer significantly. The process regime for the increasing of the thinning rate and concomitant reduction of the surface roughness was extended at higher Ar gas flow rates. In this way, Si wafer thinning rate as high as $20\;{\mu}m/min$ and very smooth surface roughness was obtained and the mechanical damage of silicon wafer was effectively removed. We also measured die fracture strength of thinned Si wafer in order to understand the effect of chemical dry thinning on removal of mechanical damage generated during mechanical grinding. The die fracture strength of the thinned Si wafers was measured using 3-point bending test and compared. The results indicated that chemical dry thinning with reduced surface roughness and removal of mechanical damage increased the die fracture strength of the thinned Si wafer.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.187-187
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• 2016

High intensity of population distribution in deltaic setting especially in Asia tends to have increased and causes coastal flood risk due to lower elevations and significant subsidence. Maximum or peak discharge of flood always causes numerous deaths and huge economic losses. New technology of spatial satellite image has been applied to analyze flood damage. In this research, the relationship of nightlight intensity associated with flood damages has been determined during 1992-2013 with spatial resolution of 30 arc sec ($0.0083^{\circ}$) which is nearly one kilometer at the equator in whole six countries along the Mekong River (i.e., China, Myanmar, Lao PDR, Thailand, Cambodia and Vietnam). ArcGIS Hydrological Flow Length Tool has been used to determine the distance of each pixel areas from the rivers and streams. Statistical analysis results highlight the significant correlation R = 0.47 between nightlight digital number and economic damages per unit area (US$/km2) and R = 0.62 for number of affected people for unit area ($people/km^2$). The areas near by the Mekong River and its tributaries correspond to high flood damage. This spatial analysis result is going to be prestigious key information to the regions and all related stakeholders for decisions and mitigation strategies.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.2
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• pp.110-116
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• 2022

Objective: Sperm vitrification leads to the production of reactive oxygen species (ROS) that can damage the functional parameters of sperm. The present study aimed to investigate the antioxidant effect of Nigella sativa extract on motility, plasma membrane function, mitochondrial membrane potential (MMP), DNA damage, and intracellular ROS production. Methods: A total of 20 sperm samples were used. Samples were divided into six experimental groups, including groups with aqueous extract from N. sativa seeds at concentrations of 1% to 6%, a cryopreserved control group, and a fresh control group. Results: Statistical analysis showed significantly higher total sperm motility at concentrations of 3% to 6% than in the vitrified semen control group. Additionally, progressive motility and all motion characteristics at all concentrations were significantly higher than in the vitrified semen control group. The presence of N. sativa seed extract also improved the quality of the sperm parameters assayed in all experimental groups (1%-6%; intracellular ROS production, DNA damage, MMP, and sperm membrane function) compared to the control group. Conclusion: Higher concentrations of N. sativa led to improvements in all sperm parameters and sperm quality. These findings indicate that N. sativa seed extract is effective for improving the quality of sperm after vitrification.

• Journal of Pharmacopuncture
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• v.25 no.4
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• pp.344-353
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• 2022

Objectives: Auraptene is the most abundant natural prenyloxycoumarin. Recent studies have shown that it has multiple biological and therapeutic properties, including antioxidant properties. Erythrocytes are constantly subjected to oxidative damage that can affect proteins and lipids within the erythrocyte membrane and lead to some hemoglobinopathies. Due to the lack of sufficient information about the antioxidant effects of auraptene on erythrocytes, this study intended to evaluate the potential of this compound in protecting radical-induced erythrocytes damages. Methods: The antioxidant activity of auraptene was measured based on DPPH and FRAP assays. Notably, oxidative hemolysis of human erythrocytes was used as a model to study the ability of auraptene to protect biological membranes from free radical-induced damage. Also, the effects of auraptene in different concentrations (25-400 µM) on AAPH-induced lipid/protein peroxidation, glutathione (GSH) content and morphological changes of erythrocytes were determined. Results: Oxidative hemolysis and lipid/protein peroxidation of erythrocytes were significantly suppressed by auraptene in a time and concentration-dependent manner. Auraptene prevented the depletion of the cytosolic antioxidant GSH in erythrocytes. Furthermore, it inhibited lipid and protein peroxidation in a time and concentration-dependent manner. Likewise, FESEM results demonstrated that auraptene reduced AAPH-induced morphological changes in erythrocytes. Conclusion: Auraptene efficiently protects human erythrocytes against free radicals. Therefore, it can be a potent candidate for treating oxidative stress-related diseases.

• Journal of Applied Biological Chemistry
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• v.55 no.3
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• pp.179-184
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• 2012

We investigated the cytotoxicity and oxidative DNA damage by chrysotile, one of the asbestos, in this investigation. Chrysotile enhanced malondialdehyde (MDA) levels and intracellular reactive oxygen speices generation in human airway epithelial cells. Furthermore, asbestos-induced oxidative DNA damage in lymphocytes was evaluated by single cell gel electrophoresis and quantified as DNA tail moment. Notably, phytochemicals such as curcumin, berberine, and sulforaphane presented inhibitory effect on the asbestos-induced oxidative DNA damage in lymphocytes.

• Textile Coloration and Finishing
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• v.24 no.1
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• pp.27-32
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• 2012

Generally, hair treatments by complementary actions to give a sense of activity are permanent setting, dyeing, and bleaching, etc. In this study, we investigated the wave formation ability and hair damage occuring in permanent setting and bleaching process. The wave formation ability was evaluated by the differences of length and curl diameter after permanent setting. And the hair damage was also evaluated by the protein release ability and SEM of hair. The bleached hair immediately after permanent setting treatment has better wave formation ability, but much more damaged than the bleached hair after rinsing thoroughly with warm water. It was considered that the chain of hair keratin broke down easily by the bleaching action in the existence of permanent setting agents.