• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.6
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• pp.302-308
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• 2013

In this study, we report the synthesis and characteristics of gallium oxide ($Ga_2O_3$) nanoparticles prepared by the polymerized complex method. $Ga_2O_3$ nanoparticles were synthesized using $Ga(NO_3)_3$, ethylene glycol, and citric acid as the starting materials at a low temperature of $500{\sim}800^{\circ}C$. The temperature of the weight reduction by the loss of organic precursor was revealed using TG-DTA analysis. The crystal structural change of $Ga_2O_3$ nanoparticles by the annealing process was investigated by XRD analysis. The morphologies and the size distributions of $Ga_2O_3$ nanoparticles were analyzed using SEM.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.71-80
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• 2013

According to design specifications for structural safety, a bridge in initial design step has been modelled to have larger self-weight, external loads and less stiffness than those of real one in service. Thereby measured buffeting responses of existing bridge show different distributions from those of the design model in design step. In order to obtain accurate buffeting responses of the in-site bridge, the analysis model needs to be modified by considering the measured natural frequencies. Until now, a Manual Tuning Method (MTM) has been widely used to obtain the Measurement-based Model(MBM) that has equal natural frequencies to the real bridge. However, since state variables can be selected randomly and its result is not apt to converge exact rapidly, MTM takes a lot of effort and elapsed time. This study presents Buffeting Response Correction Method (BRCM) to obtain more exact buffeting response above MTM. The BRCM is based on the idea the commonly used frequency domain buffeting analysis does not need all structural properties except mode shapes, natural frequencies and damping ratio. BRCM is used to improve each modal buffeting responses of the design model by substituting measured natural frequencies. The measured natural frequencies are determined from acceleration time-history in ordinary vibration of the real bridge. As illustrated examples, simple beam is applied to compare the results of BRCM with those of a assumed MBM by numerical simulation. Buffeting responses of BRCM are shown to be appropriate for those of in-site bridge and the difference is less than 3% between the responses of BRCM and MTM. Therefore, BRCM can calculate easily and conveniently the buffeting responses and improve effectively maintenance and management of in-site bridge than MTM.

• Nuclear Engineering and Technology
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• v.49 no.7
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• pp.1547-1554
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• 2017

VESTA (Verification of Ex-vessel corium STAbilization) and VESTA-S (-small) test facilities were constructed at the Korea Atomic Energy Research Institute in 2010 to perform various corium melt experiments. Since then, several tests have been performed for the verification of an ex-vessel core catcher design for the EU-APR1400. Ablation tests of an impinging $ZrO_2$ melt jet on a sacrificial material were performed to investigate the ablation characteristics. $ZrO_2$ melt in an amount of 65-70 kg was discharged onto a sacrificial material through a well-designed nozzle, after which the ablation depths were measured. Interaction tests between the metallic melt and sacrificial material were performed to investigate the interaction kinetics of the sacrificial material. Two types of melt were used: one is a metallic corium melt with Fe 46%, U 31%, Zr 16%, and Cr 7% (maximum possible content of U and Zr for C-40), and the other is a stainless steel (SUS304) melt. Metallic melt in an amount of 1.5-2.0 kg was delivered onto the sacrificial material, and the ablation depths were measured. Penetration tube failure tests were performed for an APR1400 equipped with 61 in-core instrumentation penetration nozzles and extended tubes at the reactor lower vessel. $ZrO_2$ melt was generated in a melting crucible and delivered down into an interaction crucible where the test specimen is installed. To evaluate the tube ejection mechanism, temperature distributions of the reactor bottom head and in-core instrumentation penetration were measured by a series of thermocouples embedded along the specimen. In addition, lower vessel failure tests for the Fukushima Daiichi nuclear power plant are being performed. As a first step, the configuration of the molten core in the plant was investigated by a melting and solidification experiment. Approximately 5 kg of a mixture, whose composition in terms of weight is $UO_2$ 60%, Zr 10%, $ZrO_2$ 15%, SUS304 14%, and $B_4C$ 1%, was melted in a cold crucible using an induction heating technique.

• Journal of Fashion Business
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• v.15 no.1
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• pp.103-114
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• 2011

This study is to provide basic information on clothing fitness necessary to develop apparel products for Korean companies that want to enter or have already made inroads into the Chinese market. In an effort to serve this purpose, a standard upper torso body model for Chinese women was established by applying the Rohrer Index and Size Designation of Clothes - Women of GB/T 1335.2-1997 to Chinese women in their 20s to determine body types and its characteristics. First, according to the result of applying the Rohrer Index to categorize body types, Type 1 showed the longest vertical body length and a short horizontal length with the lowest degree of flatness. Type 2 was a standard body type with a height of 158.73cm, weight of 53.02kg and the Rohrer Index of 1.32. Type 3 had a thick and flat body shape that had the highest degree of flatness and the shortest vertical length in its upper torso among all three types of body. Second, F-test was conducted on 4 distinctive body types obtained from comparing obesity scores to verify differences in body shapes for different degree of obesity. The test result indicated significant differences in 3 of the 4 body types and showed different structural components for different degree of obesity. Third, the result of comparing correlational distributions of body types and height range, and body types and degree of obesity for all and specified age groups revealed that about 33.30% of the body types appeared in Type2-A followed by 20.18% in Type1-A, 18.40% in Type2-Y and 7.91% in Type1-Y respectively. Body types and degree of obesity for two different age groups were most frequent in Type2-A. For the group of young women in their early 20s appeared the most in Type2-A, Type1-A, Type2-Y and Type 1-Y respectively and young women in late 20s were frequent in the order of Type2-A, Type2-Y, Type1-A and Type1-Y.

• Journal of Mechanical Science and Technology
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• v.18 no.9
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• pp.1680-1688
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• 2004

The information indicating device plays an important part in the information times. Recently, the classical CRT (Cathod Ray Tube) display is getting transferred to the LCD (Liquid Crystal Display) one which is a kind of the FPDs (Flat Panel Displays). The OLED (Organic Light Emitting Diodes) display of the FPDs has many advantages for the low power consumption, the luminescence in itself, the light weight, the thin thickness, the wide view angle, the fast response and so on as compared with the LCD one. The OLED has lately attracted considerable attention as the next generation device for the information indicators. And also it has already been applied for the outside panel of a mobile phone, and its demand will be gradually increased in the various fields. It is manufactured by the vapor deposition method in the vacuum state, and the uniformity of thin film on the substrate depends on the temperature distribution in the point-cell source. This paper describes the basic concepts that are obtained to design the point-cell source using the computational temperature analysis. The grids are generated using the module of AUTOHEXA in the ICEM CFD program and the temperature distributions are numerically obtained using the STAR-CD program. The temperature profiles are calculated for four cases, i.e., the charge rate for the source in the crucible, the ratio of diameter to height of the crucible, the ratio of interval to height of the heating bands, and the geometry modification for the basic crucible. As a result, the blowout phenomenon can be shown when the charge rate for the source increases. The temperature variation in the radial direction is decreased as the ratio of diameter to height is decreased and it is suggested that the thin film thickness can be uniformed. In case of using one heating band, the blowout can be shown as the higher temperature distribution in the center part of the source, and the clogging can appear in the top end of the crucible in the lower temperature. The phenomena of both the blowout and the clogging in the modified crucible with the nozzle-diffuser can be prevented because the temperature in the upper part of the crucible is higher than that of other parts and the temperature variation in the radial direction becomes small.

• Nutrition Research and Practice
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• v.7 no.1
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• pp.43-48
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• 2013

Quantities as well as distributions of adipose tissue (AT) are significantly related to cardiovascular disease (CVD) risk factors and can be altered with caloric restriction. This study investigated which cross-sectional slice location of AT is most strongly correlated with changes in CVD risk factors after caloric restriction in obese Korean women. Thirty-three obese pre-menopausal Korean women ($32.4{\pm}8.5$ yrs, BMI $27.1{\pm}2.3\;kg/m^2$) participated in a 12 weeks caloric restriction program. Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were measured using computed tomography (CT) scans at the sites of L2-L3, L3-L4, and L4-L5. Fasting serum levels of glucose, insulin, triglyceride, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), leptin and homeostasis model assessment-insulin resistance (HOMA-IR) were observed. Pearson's partial correlation coefficients were used to assess the relationship between AT measurement sites and changes in CVD risk factors after calorie restriction. When calories were reduced by 350 kcal/day for 12 weeks, body weight (-2.7%), body fat mass (-8.2%), and waist circumference (-5.8%) all decreased (P < 0.05). In addition, following caloric restriction, serum levels of glucose (-4.6%), TC (-6.2%), LDL-C (-5.3%), leptin (-17.6%) and HOMA-IR (-18.2%) decreased significantly (P < 0.05) as well. Changes in VAT at the level of L3-L4 were significantly greater than those at other abdominal sites, and these changes were correlated with changes in TC (P < 0.05), LDL-C (P < 0.001), SBP (P < 0.001) and HOMA-IR (P < 0.01). These results show that VAT at L3-L4 had a stronger correlation with CVD risk factors than with other AT measurement sites after caloric restriction.

• Korean Journal of Remote Sensing
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• v.36 no.2_1
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• pp.217-229
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• 2020

Recently, weather changes in Korea have intensified due to global warming, and the five major natural disasters that occur mostly include heavy rains, typhoons, storms, heavy snow, and earthquakes. Busan is vulnerable to snow disaster, given that the amount of natural disaster damage in Busan accounts for more than 50% of the total amount in the entire metropolitan cities in Korea, and that the Busan area includes many hilly mountains. In this study, we attempted to identify vulnerable areas for snowfall disasters in Busan areas using the geographic information system (GIS) with the data for both geographical and anthropogenic characteristics. We produced the maps of vulnerable areas for evaluating factors that include altitude, slope, land cover, road networks, and demographics, and overlapped those maps to rank the vulnerability to snowfall disasters as the 5th levels finally. To weight each evaluating factor, we used an entropy method. The riskiest areas are characterized by being located in mountainous areas with roads, including Sansung-ro in Geumjeong-gu, Mandeok tunnel in Buk-gu, Hwangnyeongsan-ro in Suyeong-gu, and others, where road restrictions were actually enforced due to snowfall events in the past. This method is simple and easy to be updated, and thus we think this methodology can be adapted to identify vulnerable areas for other environmental disasters.

• BMB Reports
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• v.39 no.2
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• pp.208-215
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• 2006

The human ribosomal protein S3 (rpS3) was expressed in E. coli using the pET-I5b vector and the monoclonal antibodies (mAbs) were produced and characterized. A total of five hybridoma cell lines were established and the antibodies recognized a single band of molecular weight of 33 kDa on immunoblot with purified rpS3. When the purified rpS3 was incubated with the mAbs, the UV endonuclease activity of rpS3 was inhibited up to a maximum of 49%. The binding affinity of mAbs to rpS3 determined by using a biosensor technology showed that they have similar binding affinities. Using the anti-rpS3 antibodies as probes, we investigated the cross-reactivities of various other mammalian brain tissues and cell lines, including human. The immunoreactive bands on Western blots appeared to be the same molecular mass of 33 kDa in all animal species tested. They also appear to be extensively cross-reactive among different organs in rat. These results demonstrated that only one type of immunologically similar rpS3 protein is present in all of the mammalian brain tissues including human. Furthermore, these antibodies were successfully applied in immunohistochemistry in order to detect rpS3 in the gerbil brain tissues. Among the various regions in the brain tissues, the rpS3 positive neurons were predominantly observed in the ependymal cells, hippocampus and substantia nigra pars compacta. The different distributions of rpS3 in brain tissues reply that rpS3 protein may play an important second function in the neuronal cells.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.741-750
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• 2007

Objective : This study investigated the relationship between diet and lifestyle and Sasang constitution (SC) in acute stroke patients. Methods : From October 2005 to March 2007, 379 acute stroke patients were included. Patients were hospitalized within 14 days after the onset of stroke at DongGuk University International Hospital, Kyungwon University In-cheon Oriental Medical Hospital or Department Cardiovascular and Neurologic Diseases (stroke center), Kyung Hee University Oriental hospital. We assessed the type of SC of acute stroke patients by Questionnaire for Sasang Constitution Classification II (QSCC II). We investigated general characteristics, stroke types, dietary preferences (meat, sea food, fast food, alcohol drinking, coffee and green tea drinking) and lifestyle (smoking, exercise) according to SC. Results : This study showed that out of the total patients, the proportion of So-yang to Tae-eum to So-eumwas equal to 2.6 to 2 to 1. Of note, this study showed a higher proportion in age of So-eum & weight of Tae-eum. The ratio of cerebral hemorrhage to cerebral infarction was 1 to 9. SVO, LAA, SUE are the 3 types of cerebral infarction classified by TOAST; SVO ranked the highest while SUE ranked the lowest in all constitutions. There were no significant differences between So-yang and Tae-eum in the aspect of the preference for meat, but the majority of So-eum displayed high preferences for seafood. In the aspect of alcohol drinking and smoking history, So-yang recorded significantly bigger proportion while So-eum & Tae-eum patients represented a bigger proportion than So-yangin the aspect of no exercise habits. Conclusion : According to the result above, we could observe the general disposition of various characteristic distributions according to SC of acute stroke patients. Also, we could observe a relationship between diet and lifestyle and Sasang constitution (SC) in acute stroke patients. Further studies will be needed to better understand the relationship between diet and lifestyle and Sasang constitution (SC) in acute stroke patients.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.3
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• pp.173-179
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• 1990

The effect of a highly water absorbing polyacrylate polymer, commonly called K-sorb, at rates of 0.0, 0.05, 0.2, and 0.5% by weight on the water retention properties of three soils, and the longevities of these treatment effects were evaluated. Water retentions were measured for all the treatments by use of a pressure-plate extractor in the laboratory. Available water and three-phase distributions at moisture tensions of 0.01, 0.3, and 15b were calculated from water retentivity data. A randomized block experiment of Chinese cabbages was conducted to examine the effects and the longevities of the treatments(0.0, 0.05, 0.1, and 0.2%) on water retention of Jungdong sandy loam soil in the field. Water retentions for a loamy sand, sandy loam, and loam soil, treated with 0.2 and 0.5% K-sorb, were increased. K-sorb treatments were more effective in sandy soil than in loamy soils. Water contents for the 0.5% treatment were markedly greater than those for the 0.2% treatment at earth moisture tension. K-sorb only at a rate of 0.5% remained effective in water retention of each soil through repeated drying and wetting for 12 months. Duncan's multiple range showed 0.2% treatment was effective(at the level of 0.05) after 2 months but not after 10 months under field condition.