• The Journal of Engineering Geology
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• v.23 no.2
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• pp.105-115
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• 2013

Increasing the river cross-section by barrage construction causes rises in the average river water levels and discharge rates in the rainy season. The time series patterns for groundwater levels measured at 23 riverside monitoring wells along the lower Nakdong River are compared for two cases: before and after water-filling at the Changnyeong-Haman Barrage. Monthly average groundwater levels indicate a distinct increase in groundwater levels in the upstream riverside close to the barrage. River-water level management by barrage gate control in August, during the rainy season, resulted in a 0.1 m decrease in groundwater levels, while water-filling at the barrage in December caused a 1.3 m increase in groundwater levels. The results of hierarchical cluster analysis indicate that seven groundwater monitoring wells and river water levels were in the same group before barrage construction, but that this number increased to 14 after barrage construction. Principal component analysis revealed that the explanation power of two principal components corresponding to river fluctuation, PC1 and PC2, was approximately 82% before barrage construction but decreased to 45% after construction. This finding indicates that the effect of the river level component that contributes to change in groundwater level, decreases after barrage construction; consequently, other factors, including groundwater pumping, become more important. Continuous surveying and monitoring is essential for understanding change in the hydrological environment. Water policy that takes groundwater-surface water interaction into consideration should be established for riverside areas.

• Convergence Security Journal
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• v.13 no.5
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• pp.107-116
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• 2013

Occur in various parts of the world and the new aspects of the regional conflict is spreading. Nation and civilization, one based on religious ideology, hegemonic tendencies areas of conflict are factors that appear. It has the characteristic that inheritance and conflict between civilizations is spreading. Christian and Islamic books, especially the confrontation and conflict is surfaced in the international political aspects, and a threat to the security of the human race is approaching. To assert the superiority of Western Christianity emerging countries, the salvation of mankind and world peace mission with the historical non-democracy, human rights, women's rights, underdevelopment, nuclear issues, and the spirit of Christian civilization, considered to be linked and reverse, Democracy Launching and human rights issues are forcing Western development model. Islam believes in absolute monotheism that God Lord only determined by the 'slave' and having the determination to serve the religious, political, social and cultural nature ingrained, and closely adjacent to each other geographically, to focus on in quency characteristics higher than the other civilizations are appearing. To assert the doctrine of non-violent Islam 'Koran' and 'knife' became known as the violent images appear in the armed conflict between the culture method. Today the world is facing a clash of civilizations is derived from the religious conflicts and confrontation and friction between the nations appear. In particular, the deep religious roots of Christianity and Islam, the Arab-Israeli conflict, including the right to live in strife confrontation between Christianity and Islam was spread. By a factor of civilization and the spread of terrorism occurred historically proven came here from all over the earth that is being generated is true. Civilization are the symbol of the nation and the species identity.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.1
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• pp.7-18
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• 2012

So many researchers have been interested in key success factors of technological start-ups. However, even previous studies have focussed on key success factors, as their findings have not been consistent. The purpose of this study is to investigate the determinants of technological start-ups' performance. The first aim of this study is intended to explores impact of entrepreneurs' characteristics, technological capabilities and network on firm performance. The second aim is to examine the causal relationships among latent variables with firm performance and with the use of path analysis. For this study, information has been gathered through surveys from entrepreneurs of 701 Korean technological start-up companies. As for analysis of the data, SPSS 18.0 OK for Windows and AMOS 4.0 were used for testing of hypothesis. Results of the hypothesis testing are summarized as follows: First, it was found that entrepreneurs' characteristics, technological capabilities and network had statistically significant influence on firm performance. Second, entrepreneurs' characteristics had significant influence on technological capabilities and network. Third, network did not have significant influence on technological capabilities. The major contributions of this study are (1) identifying the determinants on firm performance of technology-based start-ups by means of structural equation model, (2) verifying effects on firm performance of technology-based start-ups by the variables.

• Journal of Life Science
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• v.9 no.2
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• pp.194-200
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• 1999

Grinding aid is a necessary unit operation when the raw materials are handled in solid form, and the purpose is to improve the bioavailability by reducing the particle size. For the particle design of pefloxacin, the dry planetary ball-mill was used. With the drying process, 330 g of zirconia ball with its size of 2 mm in diameter and 10 g of pefloxacin were transferred to the pot and mixed well. The mixture was ground at 112 rpm (60 Hz) for 15, 30, and 60 min, respectively. The most satisfactory grinding products were generated at 15 min of grinding time for their particle size. The volume mean diameter $\X_50$ of the grinding products was 2.97 $\mu$m. X-ray diffraction (XRD), differential scanning calorimeter (DSC), and infrared spectroscopy (IR) patterns were relatively unchanged before pulverizing pefloxacin and in the progress of grinding. Thus, these results suggest that this pulverizing method can be used for grinding products without evident effect on stability of the drug pefloxacin. Dissolution test was carried out to set up the optimal detective condition against residual antibacteria of fish by HPLC. The grinding pefloxacin for 15 min is most effective in dissolution test.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.257-267
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• 2004

Our study investigated the association between solvent exposure and acquired color vision loss using the Lanthony D-15 desaturated panel in petrochemical industry. Since neurotoxic effects associated with chronic solvent exposure, subjects with more than 6 months of exposure were included. Exposure assesment was estimated mean, maximum and cumulative 8hr TWA from individual 8-hour sampling. Exposure status were classified into two groups, occupationally exposed group to solvent and a non-exposed group. The results showed that CCI was positively related for age. According to the results of qualitative analysis, there was no significant difference in the prevalence of specific Type of dyschromatopsia the two examined group. However, the prevalence showed a higher proportion of dyschromatopsia to solvent exposure. It was affect with acquired dyschromatopsia(Type II, III and Complex) in exposed worker group(5.9%,7.86%,14.99%, respectively) than in the nonexposed group(6.16%,7.55%,13.71%, respectively). After each variable was adjusted for age, alcohol and tobacco consumption, a relationship between acquired dyschromatopsia and exposure showed an increase in the Odds ratio as compared to the nonexposed group at only left. The results showed that acquired dyschromatopsia was positively related to age (p<0.001). The results showed that solvent exposure, although not significant, could cause the acquired dyschromatopsia and visual system can serve important information on early neurotoxic effects in generally. Therefore, we need to concerns about eye health in workers.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.9
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• pp.843-852
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• 2009

In this paper, we present design, fabrication, and measured results for a frequency upconverter for a wireless communication system of UAV(Unmanned Aerial Vehicle). The specifications of such wireless communication system requires the special features of maximum range of communication as well as deployment in UAV and repairing. The frequency upconverter operating at $5.25{\sim}5.45\;GHz$ in C-band was designed and fabricated considering such special features. The AGC function was included because the required output power should be constant for optimal system operation. The fabricated upconverter showed a constant output power of $+2{\pm}0.5\;dBm$ for the $-15{\sim}-10\;dBm$ input. Spuriouses were below -60 dBc and the adjacent leakage power was below -40 dBc. In addition, LO sources in the upconverter was implemented using the frequency synthesizer with step 1 MHz. This is for the application to the situation where multiple UAVs employed and the possible change of the permitted frequency band. The synthesizer showed a phase noise of -100 dBc/Hz at the 100 kHz frequency offset.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1349-1356
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• 2014

This study investigated the biological activities of 70% methanol extracts from black chokeberry and blueberry by measuring DPPH, superoxide anion and ABTS radical scavenging activities, metal chelating effect, reducing power, and nitrite scavenging activity. Extraction yields of black chokeberry and blueberry were 62.90% and 67.09%, respectively. Total polyphenol and total flavonoid contents were 117.20 mg/g and 32.50 mg/g for black chokeberry and 42.26 mg/g and 26.39 mg/g for blueberry, respectively. Black chokeberry had higher antioxidant activity than blueberry. DPPH and ABTS radical scavenging activities, nitrite scavenging activity, and metal chelating effect of black chokeberry were 98.29%, 96.68%, 97.64%, and 91.33%, respectively, at a concentration of 5 mg/mL, which were equal to those of ascorbic acid (positive control). These results suggest that black chokeberry has potent biological activities, and in the future, the availability of black chokeberry will increase in the field of value added food products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.957-963
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• 2013

This study evaluated the quality characteristics of muffins prepared with different amounts (0%, 4%, 8%, or 12%) of apricot powder. The moisture content was higher in groups containing 8% and 12% apricot powder. The specific volume of muffins decreased as the amount of apricot powder increased. The lightness value was lower in groups containing apricot powder, with redness and yellowness values increasing with increasing amounts of apricot powder. Rheology tests showed no significant differences in hardness, springiness, and cohesiveness between control muffins and muffins with apricot added. Scanning electron microscopy showed that the number and size of air cells decreased with increasing levels of apricot powder. The substitution of wheat flour with apricot powder yielded muffins with a higher DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging activity and total polyphenol content. Consumer acceptance tests revealed no significant differences in appearance, smell, and texture between muffin samples, but the taste and overall acceptability scores were lowest for muffins with 12% apricot added. Therefore, up to 8% apricot powder can be incorporated into muffins to meet the sensory quality and functional needs of the consumer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.927-932
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• 1998

The antioxidant activity of Symphyocladia latiuscula was determined by measuring lipid peroxide produced when a mouse liver homogenate was exposed to the air at $37^{\circ}C$, using 2-thiobarbituric acid (TBA) and radical scavenging effect on 1,1 - diphenyl - 2 - picrylhydrazyl (DPPH) radical, and free radical generation inhibition by $ACF_2$(Hepatocyte). The methanol extract of S. latiuscula showed high antioxidant activity. And the methanol extract was fractionated with several solvents. With regard their fractions, the antioxidant activity were in the order of dichloromethane > hexane > butanol > ethyl acetate > water fraction. The dichloromethane fraction showed the strongest radical scavenging activity ($50\%$ inhibitory concentration[$IC_{50}$]=3,14 $\mu$g/ml), and strong inhibitory effect on the lipid peroxidation of the mouse liver homogenate, which was compared with lascorbic acid, inhibition effect was stronger than Lascorbic acid. The methanol extract of S. latiuscula and its dichlromethane soluble fraction also inhibited over $50\%$ at concentration of 0.2 mg/ml and 0.1 mg/ml on free radical generation of hepatocyte ($AC_2F$). While the water fraction was inactive in all the assay for antioxidant activity.

• Journal of Preventive Medicine and Public Health
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• v.38 no.4
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• pp.415-419
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• 2005

Objectives : We wanted to evaluate the relationship between obesity and left colonic adenomatous polyps in Korean adult men. Methods : This study was conducted among 575 adults men (aged between 40 and 69), who had colonoscopy done from January to December 2002 during a routine health examination at Health Promotion Center, Ulsan University Hospital. The patients' colons were examined up to splenic flexure by using fiberoptic colonoscopy. A questionnaire survey on behavioral factors and physical measurements were also done. The body mass index (BMI) and waist-hip ratio (WHR) were used as the indices of obesity. The BMI was categorized into three levels: normal ($BMI{\leq}22.9$), overweight ($23{\leq}BMI{\leq}24.9$), and obese ($BMI{\geq}25.0$). The WHR was categorized into four levels with cutoff points at the 30th, 60th, and 90th percentile of the control group. Age, education, smoking, alcohol use and exercise were controlled for by performing multiple logistic regression analysis. Results : There were 99 cases of colonic adenomatous polyps. Four hundred seventy six subjects with normal colonoscopy findings served as the control. The BMI and WHR were associated with the adenomatous polyps (odds ratio, 1.81 [95% CI=1.02-3.19] for a $BMI{\geq}25.0$ as compared with a $BMI{\leq}22.9$, odds ratio, 3.94 [95% CI=1.77-8.77] for a $WHR{\geq}0.95$ as compared with a $WHR{\leq}0.86$). The BMI was not associated with the risk of adenomatous polyps after additional adjustment was made for the WHR, but the association between the WHR and adenomatous polyps was still positive and independent of the BMI (odds ratio, 4.15 [95% CI=1.63-10.59]). Conclusions : The results support that obesity, and particularly abdominal obesity, can be associated with an increased risk of incurring colonic adenomatous polyps.