• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.665-668
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• 1997

We fabricated a number of optical fiber Bragg gratings by varying the UV beam parameters such as the laser energy density, pulse repetition rate and exposing time. The reflectance and the Bragg wavelength shift of the fiber Bragg gratings formed with a KrF excimer laser in real time depend strongly on the UV beam parameters. The index changes in the gratings during the exposing time are well fitted to the well known equations.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1177-1178
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• 2015

국내 전력설비는 70년대 이후 제3차 경제개발 5개년 계획에 따라 중화학공업의 발전과 함께 급속히 성장해왔다. 과거 개발 위주의 산업구조에서 급속히 팽창한 전력설비는 21세기에 들어서면서 30~40년 장기 사용에 따른 노후화가 진행되었고, 증가하는 전력수요에 대응하기 위한 발전 및 송전 용지 확보의 어려움으로 인하여 전력설비의 신규 증설에 많은 어려움을 격고 있는 실정이다. 따라서 전력설비의 안전성과 신뢰성을 확보하기 위해 적절한 교체시기 선정 및 최적의 자산관리 필요성에 대해서 최근 관심을 가지기 시작하였고, 이러한 전력설비의 최적 자산관리에 핵심적인 전력설비의 상태평가 기술의 발달로 과거 시간기준의 유지보수(Time Based Maintenance)에서 최근 노후설비의 증가와 진단기술의 발달에 따른 예방보전(Preventive Maintenance)에 의한 상태기준 유지보수(Condition Based Maintenance)개념으로 전환되고 있다. 고전압 회전기기(발전기, 전동기)의 상태평가를 위한 핵심기술인 Off-line 부분방전시험이 널리 적용되고 있으며, 본 논문에서는 부분방전 측정 시험 시 대상설비 단자부의 인출케이블에 의한 감도저하 현상에 대해 고찰 하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04b
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• pp.1097-1100
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• 2001

소프트웨어 개발자로부터 독립된 소프트웨어 시험자가 수행하는 소프트웨어 시험은 소프트웨어의 안전성 향상을 위해 필요하다. 컴퓨터기반의 디지틀시스템으로 설계되는 일체형원자로 MMIS에 적용하기 위한 소프트웨어 시험 계획을 개발할 필요가 있다. 본 논문은 소프트웨어 시험 계획을 소프트웨어시험 조직 구성, 시험 문서, 시험 절차, 시험 방법을 중심으로 제시한다. 소프트웨어 시험 방법은 원시코드 정적분석과 동적시험을 구분하여 기술한다. 본 논문에서 제시된 소프트웨어 시험 계획은 원자력 규제기관에서 요구하는 소프트웨어 시험 요구사항을 만족한다. 본 논문을 통해 제시된 소프트웨어 시험 계획을 일체형원자로 MMIS 소프트웨어 개발 시 적용하여 소프트웨어 고장율 데이터를 수집할 예정이다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.2
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• pp.83-92
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• 1998

To evaluate the hydraulic resistance behind bodies in a large scale grid numerical model, a drag stress term which is formulated by the drag force is introduced in the depth-integrated Reynolds equations. And also, the applicability and problems of this model are discussed through various numerical experiments where the analytical solutions exist. In the case of a single body, the error range of velocity difference between analytical and numerical solutions is within $\pm$10% and the wake width behind the body shows a good agreement with the analytical solution. When the drag coefficient and the eddy viscosity are precisely decided, the numerical solutions behind a row of bodies will be efficiently used in real situations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.1
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• pp.90-97
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• 1992

An estimation method for the amplitude and phase response of transmission line is discussed. and applied to narrow band ISDN subscriber line. The ABCD parameters of line are evaluated from four impedance values: the standard termination impedence at activated and deactivated stares, and the input impedances of line which can be estimated at each state. Estimating input impedence, the “chirp” signal is used as incident signal and noise effect can be reduced by ensemble averaging. These ABCD parameter estimations might be applicable to ether uniform or nonuniform line. Cleary the magnitude and phase response can be obtained from estimated ABCD parameters. The numerical simulation results for N ISDN subscriber line model are included, and the estimation error introduced by deviation in load impedence is also anlyzed.

• Korean Journal of Health Education and Promotion
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• v.31 no.1
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• pp.13-26
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• 2014

Objectives: This study aimed to assess whether metabolic syndrome (MS) is related to osteoporosis and investigate the association between the MS components and bone mineral density (BMD). Methods: We conducted a cross-sectional study for 4,365 women aged over 50 years who completed health examination from 2008 to 2012 in Korea Association of Health Promotion Gangwon Branch. Height, body weight, waist circumference, blood pressure, fasting plasma glucose, serum lipid profiles, and BMD were measured. Results: Obesity measured as body mass index (BMI) was detrimental to all of the MS components but positively correlated with BMD at three skeletal sites (lumbar spine, femoral neck, and total hip). There were no significant differences in the MS prevalence between women without osteoporosis and those with osteoporosis. In age-adjusted analysis, women with MS had significantly higher BMD at three sites when compared to those without MS. After adjusting for BMI and age, these significances disappeared, such that MS was not associated with higher BMD. Conclusions: Our findings indicate that obesity increases the risk of MS whereas underweight increases that of osteoporosis. The association between MS and higher BMD was explained by the higher BMI in those with MS. MS may not be associated with osteoporosis.

• YAKHAK HOEJI
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• v.35 no.3
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• pp.182-189
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• 1991

Systematic study on the extraction of ion pair by the use of picric acid (PCA) as an ion pair forming reagent to the aliphatic amines has not be done by spectrophotometric method. The extraction of ion pair by the use of PCA and 23 kinds of the aliphatic amines was examined. The procedure is as follows; Elving's buffer solution (pH 1.3~10, ionic strength 0.5) each amine solution, and PCA solution were taken into a test tube. The mixture was shaken mechanically with chlorform. The organic phase was filtered through a filter paper to remove water droplets. The absorbance was examined at $\lambda_{max}$ against a reagent blank. Primary and secondary whose carbon number were more than 7 or 6, respectively, are extractable as ion pairs with PCA, while tertiary amines and quaternary ammonium salts are also extractable without the correlation of carbon number. It was considered that the ion pair extraction of primary and secondary amines was affected by the number of carbon of amines, but its extraction of tertiary amines or quaternary ammonium salts was affected by kind of aliphatic amines rather than pKa values or carbon number of amines.

• Journal of Aquaculture
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• v.10 no.4
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• pp.439-447
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• 1997

A specific disease syndrome, which led to massive mortality on the Korean mandarin fish fingerling (Sinperca scherzeri) at Chongpyong Inland Fisheries Institute was atudied. The causetive agent isolated from the diseased fish was identified as Aeromonas hydrophila on the basis of biochemical and physiological characteristics. Infection experiments in the Korean mandarin fish fingerling, weighting 3-4 g with A. hydrophila were conducted by immersion, oral administration, intramuscular injection, and injection of the soluble extracellular products secreted from it. Motality rate was higher virulence in intramuscular injection group than other experimental groups. In injection group of the soluble extracellular products, all fish treated with high concentration ($8{\times}10^9$ cfu/ml) were repidly killed into 3-6 hrs. There results show that the Korea mandarin fish fingerling has high susceptibility to A. hydrophila.

• Korean Journal of Pharmacognosy
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• v.35 no.1 s.136
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• pp.35-40
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• 2004

Seven terpenoids, trans-phytol (1), ${\alpha}-spinasterol$ (2),${\beta}-sitosterol$ (3), oleanolic acid (4), traxasterol (5), ${\alpha}-spinasterol\;3-O-{\beta}-D-glucopyranoside$ (8), ${\beta}-spinasterol\;3-O-{\beta}-D-glucopyranoside$ (9), and three glycerides, 3-O-(9Z, 12Z, 15Z-octadecatrienoyl) glycerol (6), 3-O-(9Z, 12Z-octadecadienoyl) glycerol (7), 1, 2-O-(9Z, 12Z, 15Z-dioctadecatrienoyl)-3-O-${\beta}$- D-galactopyranosyl glycerol (10) were isolated from n-hexane fraction of the aerial parts of Saussurea nutans which was used as Korean traditional medicine to σeat rheumatic arthritis and dysmenorrhea. Their structures were established by chemical and spectroscopic methods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.926-931
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• 2007

Diarrhetic shellfish poisons (DSP) such as okadaic acid (OA), dinophysistoxin-1 (DTX1), pectenotoxin-1(PTX1), PTX2, PTX6 and yessotoxin (YTX) were determined simultaneously by LC-MS/MS and mouse bioassay in the shellfishes (oyster, mussel, Washington purple clam, ark shell, scallop and short necked clam) collected at Tongyeong, from March to September, 2006. Oyster and mussel were found to contain DSP (0.05${\sim}$0.1 MU/g) in March by mouse bioassay; however, no DSP components were detected on the LC-MS/MS. Also, a small amount of DTX1 (0.05 ${\mu}g/g$) in mussel (June) and OA (0.01${\sim}$0.02 ${\mu}g/g$) in 5 species of shellfishes(August) were determined by LC-MS/MS.