• The Journal of Engineering Geology
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• v.29 no.2
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• pp.99-112
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• 2019

Rainfall infiltration through the unsaturated zone is influenced by a range of factors including topography, geology, soil, rainfall intensity, temperature and vegetation; the actual infiltration varies largely in time and space. The infiltration capacity of soil is a critical factor in identifying groundwater recharge and leakage of surface water. It may differ depending on soil types and geological features of a particular basin or territory as well as on the usage of the land. This study was conducted in forest and farmland region of the mid-mountain area (EL. 50~300 m) of Jeju Island to test soil infiltration capacity of the area where rainfall contributes to groundwater. Results were analyzed using the four soil group classification methods presented by Jeong et al. (1995) and NAS (2007) to discover that the method offered by NAS (2007) is more reliable in the mid-mountain area of Jeju Island. The study compares and reviews the existing classification methods using the results of infiltration capacity tests executed on different soil groups throughout the whole region of the Jeju mid-mountain area. It is expected that this work will serve as a guideline for evaluating surface water recharge and hydraulic characteristics of Jeju Island.

• Journal of Korean Society on Water Environment
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• v.25 no.2
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• pp.281-287
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• 2009

Achieved monitoring regularly about fishway that is a intake dam belongings to Kyeongchon for 5 years. Result that achieve monitoring, discovered pressing issue of opening and closing degree of discharge control part in fishway. In this research, analyze discharge relation with fishway and intake sluice and presented operation plan of opening and closing of discharge control part. Investigated necessity intake discharge and benefited area to analyze relation of discharge that is flowed in fishway and discharge escaping by intake sluice. When opened discharge control part step by step gradually, analyzed discharge. Compared with survey discharge making ration curve of fishway and intake sluice using orifice and submerged weir formula. Because operation of intake dam is necessary intake discharge and upriver inflow discharge by time, operation uses by survey discharge and calculated opening discharge of fishway by opening discharge of intake sluice via monthly inflow discharge. To sum up, calculated floodgate opening height of fishway by water level to present maintenance standard of intake dam.

• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.411-420
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• 2017

Objective: The purpose of this study is to analyze the accident characteristics according to the gender of the injured workers in building cleaning and to reflect them in the Industrial Accident Prevention Policy. Background: An analysis of industrial accidents is an essential process for establishing systematic industrial accident prevention measures. In order to establish industrial accident prevention measures for workers effectively, it is necessary to analyze accident characteristics by job type for workers who do the same work. Method: In this study, we analyzed the accident characteristics of 1,645 janitors who were approved of work-related injuries in 2015. We also analyzed the characteristics according to gender by dividing them into worker-related factors and accident-related factors. Results: The accidents caused to the janitors showed different characteristics according to gender, age, work experience, agency of accident, and distribution of original cause materials. In other words, 70.2% occurred to workers over 60 years old and 56.2% occurred to unskilled workers with less than a year of work experience. In the case of accident pattern, 79.1% occurred in tripping (slip) hazards, and 68.2% of accidents occurred on the floor (including the ground) and the stairs, indicating that the accident occurred most frequently during cleaning work on the floor or stairs. Conclusion and Application: The results of the study on the accident characteristics of the janitors can be used as basic data for systematic preventive measures against accidents occurring to the elderly female workers in the service industry.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.543-548
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• 2014

In this paper, the dielectric relaxation and reliability of high capacitance density metal-insulator-metal (MIM) capacitors using $Al_2O_3-HfO_2-Al_2O_3$ and $SiO_2-HfO_2-SiO_2$ sandwiched structure under constant voltage stress (CVS) are characterized. These results indicate that although the multilayer MIM capacitor provides high capacitance density and low dissipation factor at room temperature, it induces greater dielectric relaxation level (in ppm). It is also shown that dielectric relaxation increases and leakage current decreases as functions of stress time under CVS, because of the charge trapping effect in the high-k dielectric.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.2 s.314
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• pp.137-143
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• 2007

The P-ECLMS algorithm adapted the existing Post-Processing method occurs the distortion of the near-end signal at the double-talk situation. To solve this problem, we propose the SP-ECLMS algorithm which makes the Post-Processing coefficient differently at the case of the single-talk and the double-talk. When the correlation level is not output less than 30%, the proposed algorithm output the original signal to prevent the signal's distortion.

• Applied Biological Chemistry
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• v.41 no.8
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• pp.600-604
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• 1998

Methanol extracts from 53 species of oriental medicinal plants in 34 families were tested for their fungicidal activities against Pyricularia grisea, Rhizoctonia solani, Phytophthora capsici, Phytophthora infestans, Collectotrichum dematium, Botryospaeria dothidea, Fusarium oxysporum f. sp. cucumerinum, Botrytis cinerea, Puccinia recondita, and Erysiphe graminis. In in vitro study using impregnated paper disc method, the efficacy varied with both plant pathogen and plant species tested. Methanol extracts of Asarum sieboldii roots, Sinomenium acutum roots, Pinus densiflora leaves, Rheum undulatum root barks, Coptis japonica roots, and Phellodendron amurense barks showed potent fungicidal activities against the various pathogens when treated with 10 mg/disc. In a whole plant test, methanol extracts of P. densiflora leaves and roots and C. japonica roots were highly effective against a variety of plant pathogens. As a naturally occurring fungicide, P. densiflora- and C. japonica-derived materials could be useful as new fungicidal products against various plant diseases induced by plant pathogenic fungi.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.4
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• pp.154-158
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• 2013

The unnatural dead body refers to a corpse which is suspicious of unusual death and the dead case has been occurred more than 20 thousands times every year during the recent five years and most of them are found decayed. Police Scientific Investigators investigate unnatural dead bodies and its surroundings in all-around way and determine whether the death is involved with a crime, and most of the Scientific Investigators are exposed to a danger to get infected with pathogenic bacteria which are generated during the decaying process of dead body and are mostly to cause serious injuries on human beings. In line with the fact, the present study conducted a bacterial analysis by collecting excretions from 60 dead bodies and culturing the bacteria to evaluate infection risk of the police agents. The study cultured bacteria from 60 bodies and classified pathogenic bacteria of 108 strains, and its main bacteria are found to be them (; Acinetobacter baumannii 20 strains (19%), Pseudomonas aeruginosa 19 strains (18%), E. coli 18 strains (17%), Klebsiella pneumoniae 11 strains (10%), Proteus mirabillis 10 strains (9%), Enterococcus faecium 10 strains (9%), Staphylococcus aureus 9 strains (8%), Bacillus spp. 5 strains (5%), Streptococcus pneumoniae 3 strains (3%), Candida albicans 2 strains (2%), Mycobacterium tuberculosis 1 strains (1%)). The study results are expected to be used as educational data for preventing the Police Scientific Investigator from infections with bacteria or as a minimum data for improving work environment of the agents.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.183-188
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• 2005

레이더강우관측의 수문학적 적용성을 검토하고 개념적 유출모형과 분포형 유출모형에서 지점강수 및 레이더강수를 적용하여 매개변수의 민감도 및 수문곡선변화를 관찰하였다. 레이더강수의 계통적오차는 총강수량비를 이용하여 보정하였고, 이결과 레이더강수가 지점강수에 비하여 첨두강수를 더욱 양호하게 표현하고 있음을 확인할 수 있었다. 지점강수와 레이더강수를 이용하여 용담댐 상류유역에 대한 유출해석을 수행하였다. 개념적모형으로는 저류함수모형을, 분포형모형으로는 실시간 홍수 조절을 목적으로 미국 Oklahoma대학에서 개발된 $V\;flo^{TM}$모형을 이용하여 테스트하였다. 결과 개념적 모형과 분포형모형 모두에서 경험식으로부터 구한 매개변수의 초기값을 이용한 수문곡선은 관측수문 곡선과 상당한 차이를 보이고 있었으나 분포형 수문곡선의 경우 천천상류지점의 수문곡선은 매개변수의 추가적 보정이 필요없을 정도로 매개변수의 초기값이 수문곡선을 잘 모의 하고 있었다. 이는 매우 고무적인 결과로서 실시간 홍수모형으로서 요구되는 중요한 특성과 동시에 물리적 기반의 분포모형의 가장 큰 장점일 수 있는 사상독립적 유역매개변수군을 구축하는데 중요한 단서가 될 것으로 보여진다.

• Macromolecular Research
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• v.11 no.6
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• pp.444-450
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• 2003

Hydrophobically End-capped polyethylene oxide Urethane Resin(HEUR)-associating polymers, HEUR 35(8), HEUR 35(12), and HEUR 35(18), comprise a polyethylene oxide (PEO) having a molecular weight of 35,000 that is end capped with two C$\_$8/H$\_$17/, C$\_$12/H$\_$25/, and C$\_$18/H$\_$37/ alkyl chains, respectively. These associating polymers were synthesized by condensation reactions with polyethylene oxides and alkyl isocyanates. The self-diffusion coefficients of HEUR-associating polymers were measured in aqueous solution by pulsed-gradient spin-echo (PGSE) nuclear magnetic resonance (NMR) spectroscopy. All polymers underwent a decrease in their mean diffusion coefficients as the concentration was increased. However, the dispersion of the diffusion coefficients, ${\beta}$, about the mean fluctuated with changes in concentration. The large dispersion at low concentrations of HEUR 35(8) and HEUR 35(12) is related to the interaction between hydrophobic end groups, and the large dispersion at high concentrations of HEUR 35(18) is correlated with transient network formation. These results are valuable for predicting the associating mechanism of the large aggregates before and after their critical micelle concentration.

• BMB Reports
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• v.32 no.6
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• pp.521-528
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• 1999

The folding of recombinant hepatitis B virus X-protein (rHBx) solubilized from Escherichia coli inclusion bodies was investigated. By sequential dialysis of urea, rHBx was folded into its native structure, which was demonstrated by the efficacy of its transcriptional activation of the adenovirus major late promoter (MLP), fluorescence spectroscopy, and circular dichroism (CD) analysis. The decrease in CD values at 220 nm and a corresponding blue shift of the intrinsic fluorescence emission confirmed the ability of rHBx to refold in lower concentrations of urea, yielding the active protein. Equilibrium and kinetic studies of the refolding of rHBx were carried out by tryptophan fluorescence measurements. From the biphasic nature of the fluorescence curves, the existence of stable intermediate states in the renaturation process was inferred. Reverse phase-high performance liquid chromatography (RP-HPLC) analysis further demonstrated the existence of these intermediates and their apparent compactness.