• Economic and Environmental Geology
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• v.24 no.4
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• pp.347-361
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• 1991

The Sangeun ore deposit is located in a volcanic belt within the Gyeongsang Basin in south western Korea. The ore deposit is of representative epithermal Au-Ag quartz vein type developed in lapilli tuff. This paper presents the mineralization with special emphasis on mineral zoning of the deposits. Principal points are summarized as follows: (1) Four stages of mineralization are recognized based on macrostructures. From ealier to later they are stage I(arsenopyrite-pyrite-quartz), stage II(Au-Ag bearing Pb-Zn-quartz), stage III(barren quartz), and stage IV(dickite-quartz). (2) Electrum principally occurs with arsenopyrite and galena in stage II, and has chemical compositions of 72.9-67.1 Ag atom %, and has Ag/Au ratio of 2.69-2.04. (3) Sphalerite varies in its FeS content according to the mineralization stages; 22.03-18.60 mole % FeS and 1.33-0.23 mole % MnS in stage IB, 16.11-8.64 mole % FeS and 1.33-0.23 mole % MnS in stage II. (4) Alteration zones of mineral assemblage, from the vein to the wall-rock, consist of sericite - quartz - pyrite, sericite - quartz - dickite, sericite - chlorite plagioclase respectively.

• Korean Journal of Materials Research
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• v.25 no.4
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• pp.183-190
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• 2015

Fatigue crack growth rate tests were conducted as a function of temperature, dissolved hydrogen (DH) level, and frequency in a simulated PWR environment. Fatigue crack growth rates increased slightly with increasing temperature in air. However, the fatigue crack growth rate did not change with increasing temperature in PWR water conditions. The DH levels did not affect the measured crack growth rate under the given test conditions. At $316^{\circ}C$, oxides were observed on the fatigue crack surface, where the size of the oxide particles was about $0.2{\mu}m$ at 5 ppb. Fatigue crack growth rate increased slightly with decreasing frequency within the frequency range of 0.1 Hz and 10 Hz in PWR water conditions; however, crack growth rate increased considerably at 0.01 Hz. The decrease of the fatigue crack growth rate in PWR water condition is attributed to crack closure resulting from the formation of oxides near the crack tips at a rather fast loading frequency of 10 Hz.

• Journal of the Korean Data and Information Science Society
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• v.11 no.2
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• pp.347-357
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• 2000

In this study, the buying pattern of consumers in domestic e-business is analyzed by conjoint analysis. We showed the followings through online survey: the consumers prefer comprehensive distributing company to broker type company, the product of the well-known company to that of the specialized company in brand, credit to e-money for payment. Quick delivery and the convenience in exchanges and refunds are more preferable.

• Korean Journal of Human Ecology
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• v.10 no.4
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• pp.333-347
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• 2001

The purpose of this study is to find out the washing methods specified on the care labels of vapor-permeable & water-proofed fabrics and to investigate the consumers' real washing methods in their home and their cognition. In this study, the condition of care labels on 35 products was investigated and consumers' washing methods and cognition were surveyed. The subjects were consisted of majoring clothing textiles' female, female student attending in other major and married-women. Data were analyzed SPSS 10.0. The major results were as follows : 1. The care labels of Vapor-permeable & waterproofed fabric products used in this survey followed the rule of KS K that is stated that care labels must include over 3 instructions. It was the most popular type of care labels to organize with washing methods, bleaching methods, weaving methods, drying methods, ironing methods. 2. Most consumers have vapor-permeable & waterproofed fabric products, but their consciousness of this fabric is low. The rate of consumer confirming the care labels was 76.6% but 67.8% of them answered they take care of textile products with their experiences. 3. Consumers' understanding of care instructions on care labels was investigated that most consumers understand domestic care instruction, but they didn't know almost all international one.

• Proceedings of the IEEK Conference
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• summer
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• pp.343-347
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• 2004

High oxidation temperature of SiC shows a tendency of carbide formation at the interface which results in poor MOSFET transfer characteristics. Thus we developed oxidation processes in order to get low interface charge densities. N-type 6H-SiC MOS capacitors were fabricated by different oxidation processes: dry, wet, and dry­reoxidation. Gate oxidation and Ar anneal temperature was $1150^{\circ}C.$ Ar annealing was performed after gate oxidation for 30 minutes. Dry-reoxidation condition was $950^{\circ}C,$ H2O ambient for 2 hours. Gate oxide thickness of dry, wet and dry-reoxidation samples were 38.0 nm, 38.7 nm, 38.5 nm, respectively. Mo was adopted for gate electrode. To investigate quality of these gate oxide films, high frequency C- V measurement, gate oxide leakage current, and interface trapped charge densities (Dit) were measured. The interface trapped charge densities (Dit) measured by conductance method was about $4\times10^{10}[cm^{-1}eV^{-1}]$ for dry and wet oxidation, the lowest ever reported, and $1\times10^{11}[cm^{-1}eV^{-1}]$ for dry-reoxidation

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.343-347
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• 2002

In this paper, we can easily update teaming information by using database built in web server system in implementation of a web courseware that a learner can effectively team the 'Digital Circuits' subject. Also, we offered multimedia elements such as graphics, animations, and voices etc. for increasing understanding and interaction of teaming and designed and implemented a simulation-type web courseware of practice-oriented. In result, it can encourage a learner with a motive of learning and increase effects of teaming. Also, a learner can learn various contents because we can add teaming contents to database according to needs. Furthermore, it can improve understanding for teaming by offering feedback on the result. In future, we need to design and implement circuits with more complex and many functions by adding circuit with function that can store.

• Biomedical Science Letters
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• v.25 no.4
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• pp.339-347
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• 2019

Saururus chinensis (SC) belongs to the dicotyledonous plants, and its roots, leaves and flowers are white, so it is named three hundred and seconds. It is mainly distributed in Korea, China and Japan. In Korea, it is a native plant distributed in Jejudo and Jirisan areas. It has been known to improve blood circulation, anticarcinogenic effects and purge. However, studies of the efficacy on digestive system is few. This study was conducted to evaluate the effects of oral administered-SC extract in loperimide-induced constipation rats. The amount, weight and water content of the stools were measured. The number and type of stools in the large intestines were measured, and the amount of intestinal mucus was analyzed by serological analysis and histologic special staining. The severity of constipation in SC groups was significantly less than that in control group (non-SC rats). Digital Image processing also showed weaker inflammation on the large intestines of SC groups than that of control group (non-SC group). Especially, with increased dose dependent manner of SC extract, the amount and integrity of intestinal mucus increased. These results suggest that SC extract may prevent the symptoms of constipation.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.344-347
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• 2001

A high frequency resonant inverter consisting of three unit half-bridge serial resonant inverter used as power source of induction heating at high frequency is presented in this paper. As a output power control strategy, tine-sharing gate control method is applied. The analysis of the proposed circuit is generally described by using the normalized parameters. Also, according to the calculated characteristics value, a method of the circuit design and operating characteristics of the inverter is proposed. This paper proves the validity of theoretical analysis through the experiment. This proposed inverter show that it can be practically used in future as power source system for induction heating application, DC-DC converter etc.

• Nuclear Engineering and Technology
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• v.45 no.3
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• pp.347-360
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• 2013

This paper presents an experimental investigation of the small-break loss-of-coolant accident (SBLOCA) and the loss-of-feedwater accident (LOFW) in a scaled integral test facility of REX-10. REX-10 is a small integral-type PWR in which the coolant flow is driven by natural circulation, and the RCS is pressurized by the steam-gas pressurizer. The postulated accidents of REX-10 include the system depressurization initiated by the break of a nitrogen injection line connected to the steam-gas pressurizer and the complete loss of normal feedwater flow by the malfunction of control systems. The integral effect tests on SBLOCA and LOFW are conducted at the REX-10 Test Facility (RTF), a full-height full-pressure facility with reduced power by 1/50. The SBLOCA experiment is initiated by opening a flow passage out of the pressurizer vessel, and the LOFW experiment begins with the termination of the feedwater supply into the helical-coil steam generator. The experimental results reveal that the RTF can assure sufficient cooldown capability with the simulated PRHRS flow during these DBAs. In particular, the RTF exhibits faster pressurization during the LOFW test when employing the steam-gas pressurizer than the steam pressurizer. This experimental study can provide unique data to validate the thermal-hydraulic analysis code for REX-10.

• Journal of Fashion Business
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• v.9 no.6
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• pp.126-140
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• 2005

The main purpose of this research was to examine what were the factors of shopping value that consumers perceived, if there is any difference between male and female, and if male and female consumer group were divided into different groups according to the pursuing shopping value type. Data were solicited from convenience sample of 347 adults(156 male and 191 female) who were between 19 to 49 years of age. Sources for the sample were companies and apartment complexes and several colleges in Seoul and Chonan to diversify by such demographics as age and social status. The statistical methods used for this study are factor analysis and cluster analysis and Scheffe test using a SPSS 10.00 GLM. The main findings are as follows: First, four dimensions of clothing shopping values were identified as pleasure, planned, leisure, and convenience value. For male, it appeared in the order of pleasure, leisure, planned, and convenience shopping value and for female, it appeared in the order of pleasure, planned, leisure, and convenience shopping value. The most important subdimension of clothing shopping value was 'pursuing pleasure' and the least important one was 'convenience' regardless of gender. Second, three types of consumer groups for male & female were identified. For male consumers, it appeared as planned, leisure/convenience, and pleasure pursuing group. For female consumers, it appeared as pleasure, convenience, and leisure shopping pursuing group. Here, pleasure is a common factors to affect shopping itself free from gender, but male does shopping with plan and female with pleasure.