• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.199-201
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• 1996

The design and manufacturing results of a 16 tesla/45mm bore superconducting magnet is presented. The system consists of an 8.2 tesla(at 4.2K) outer NbTi coil with a bore I.D. of 261mm, a winding O.D. of 453mm and the length of 430mm which is connected in series with a 5.6 tesla(at 4.2K) middle and a 4.7 tesla(at 4.2K) inner insert coil constructed of multifilamentary $Nb_3Sn$. The middle and inner insert coil are reacted after winding. Also, epoxy impregnation is accomplished at $Nb_3Sn$ coils using a low viscosity crack resistant epoxy which is forced into the coil with a series of vacuum and over atmosphere pressure cycle.

• 농약과학회지
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• 제8권1호
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• pp.1-7
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• 2004

화본과 제초제의 대표적인 화합물인 광학활성 fenoxaprop-p-ethyl[ethyl(R)-2-{4-(6-chloro-1,3-benzoxazol-2-yloxy)phenoxy}propionate]을 4-(6-chloro-1,3-benzoxazol-2-yloxy)phenol과 ethyl (S)-O-(p-toluenesulfonyl)lactate의 치환반응(Walden Inversion)을 이용하여 90%의 수율(광학활성순도 : 99.9% 이상)로 얻었다. 4-(6-chloro-1,3-benzoxazol-2-yloxy)phenol은 기초적인 원료인 아미노페놀, 우레아, 클로린, 유황 등을 자일렌, 메탄올, 디클로로에탄 등의 용매를 사용하여 6단계의 반응을 거처 70% 의 수율로 합성하였다.

• 한국임상약학회지
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• 제22권1호
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• pp.13-20
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• 2012

서론: 주사제 사용을 줄이기 위한 정책의 일환으로 건강보험심사평가원은 의료기관별 주사제 처방률을 통보하고 있으나, 여전히 주사제 처방은 높은 실정이다. 따라서 본 연구에서는 주사제에 대한 환자의 인식수준을 살펴보고, 환자의 주사제 요청에 영향을 미치는 요인을 파악하고자 하였다. 연구방법: 본 연구는 최근 6개월 이내에 병의원을 방문한 전국의 20세 이상의 남녀를 대상으로 전화조사한 단면설계 연구다. 환자의 일반적 특성과 주사제에 대한 태도, 인식을 조사하였고, 환자가 주사제를 요청하는데 영향을 미치는 특성을 규명하기 위해 일반적 특성(성, 연령, 결혼여부, 보험형태, 지역규모, 질환, 교육, 소득 등), 주사제에 대한 인식, 태도를 독립변수로 하고, 주사제 처방 요청여부를 종속변수로 하며, 16개 행정지역을 무작위 효과로 층화한 다수 준 분석을 실시하였다.결과: 연구대상에 포함된 응답자는 997명이었고(응답률 82.2%), 응답자 중 24%가 병의원 방문 당시 주사제를 요구했다고 응답했고, 58%가 한번 이상 주사제를 맞은 경험이 있다고 보고했다. 92%가 주사제에 대해 잘못된 인식을 갖고 있었고, 15%는 의사가 부적절하게 주사제를 처방한다고 응답했다. 다수준 로지스틱 회귀분석 결과, 남성의 경우(Odds ratio(OR) 0.71, 95% confidence interval(CI) 0.52-0.99), 고졸이상자(OR 0.63, 95% CI 0.41-0.96), 기혼자(OR 1.72, 95% CI 1.01-2.92)가 주사제를 더 요구하는 것으로 나타났고, 대도시에 비해 농촌지역 환자가(OR 2.12, 95% CI 1.24-3.63), 호흡기계 질환으로 방문한 경우(OR 1.48, 95% CI 1.03-2.12), 주사제를 처방하면 경구제에 비해 신뢰감이 생긴다는 응답자의 경우(OR 1.91, 95% CI 1.33-2.73) 주사제를 더 요구하는 것으로 나타났다. 결론: 본 연구결과 여성, 기혼자, 농촌 거주자, 호흡기계 질환으로 방문한 환자의 경우와 주사를 맞으면 신뢰감이 생긴다는 잘못된 태도를 가진 환자가 주사제를 요구하는 것으로 나타났고, 이러한 환자특성을 고려하여 주사제 사용을 감소시키기 위한 정책을 실시하는 것이 필요하겠다.

• International Journal of Ocean System Engineering
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• 제3권1호
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• pp.33-37
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• 2013

Reinforced concrete structures have been increasingly widely used in numerous industrial fields. These structures are often exposed to severely corrosive environments such as seawater, contaminated water, acid rain, and the seashore. Thus, the corrosion problems that occur with the steel bars embedded in concrete are very important from the safety and economic points of view. In this study, the effects of the cover thickness on the corrosion properties of reinforced steel bars embedded in multiple mortar test specimens immersed in seawater for 5 years were investigated using electrochemical methods such as the corrosion potentials, polarization curves, cyclic voltammograms, galvanostat, and potentiostat. The corrosion potentials shifted in the noble direction, and the value of the AC impedance also exhibited a higher value with increasing cover thickness. Furthermore, the polarization resistance increased with increasing cover thickness, which means that the oxide film that is deposited on the surface of a steel bar surrounded by alkali environment exhibits better corrosion resistance because the water, chloride ions and dissolved oxygen have difficulty penerating to the surface of the steel bar with increasing cover thickness. Consequently, it is considered that the corrosion resistance of reinforced steel can be improved by increasing the cover thickness. However, the corrosion resistance values of a steel bar estimated by measuring the corrosion potential, impedance and polarization resistance were not in good agreement with its corrosion resistance obtained by polarization curves.

• 한국환경과학회지
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• 제23권11호
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• pp.1851-1862
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• 2014

It is well known that urban relative humidity has continuous decreasing trend owing to the influence of urbanization. The change of relative humidity is directly influenced by two factors, namely, temperature effect and water vapor effect in various urban effects. In this study, the temperature and the water vapor effects on the relative humidity change were analyzed by using monthly mean relative humidities for a long period(1961~2013) in Busan and Daegu. The major results obtained in this study can be summarized as follows. Firstly, the urban dryness was caused mainly by water vapor effect in summer. But, for the other seasons, the urban dryness is mainly due to the temperature effect. Secondly, the relative humidity in Busan is on the decrease until now. This phenomenon is similar to another Korean huge cities such as Seoul, Daejeon and Incheon.

• 대한치과보철학회지
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• 제40권5호
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• pp.441-450
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• 2002

The purpose of this study was compare the fracture strength of the IPS Empress ceramic crown according to the occlusal depth (1.5mm, 2.0mm, 2.5mm) and axial inclination ($4^{\circ},\;8^{\circ},\;12^{\circ}$) of the lower second premolar. After 10 metal dies were made for each group, the IPS Empress ceramic crowns were fabricated and cemented with resin cement. The cemented crowns were mounted on the testing jig with inclination of 30 degrees and the universal testing machine was used to measure the fracture strength. The results of this study were as follows : 1. The fracture strength of the ceramic crown with 2.5mm depth and $12^{\circ}$ inclination was the highest (1284 N). Crowns of 1.5mm depth and $8^{\circ}$ inclination had the lowest strength (951 N). 2. There were no significant differences in the fracture strength by axial inclination of the same occlusal depth group. 3. Most fracture lines began at the loading area and extended through proximal surface perpendicular to the margin, irrespective of occlusal depth.

• 한국환경보건학회지
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• 제32권3호
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• pp.199-206
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• 2006

Various heavy metals have been known for causing ischemic stroke. In order to describe the causative relationship between the blood levels of various heavy metals and stroke patients, 116 patients with stroke and 111 patients without stroke were selected from one Oriental medical hospital in Wonju, Korea. Total of 9 kinds of metals such as As, Cd, Co, Cu, Hg, Mn, Ni, Pb, and Zn were analyzed in blood from patients with and without stroke. There were no significant differences in the means of metal concentrations between the stroke and nonstroke patients except for the mean of Co concentration. In the case of Co, the means for stroke and non-stroke patients were 0.44 ug/l and 0.40 ug/l showing a significant difference at the level of p-value=0.05. The odds ratios for each metal ranged from 0.96 to 2.86. Most odds ratios were not significant but the odds ratio for Co, $2.86{\pm}1.49$ was significant, indicating that Co increases the risk of stroke by 2.86 times. In order to identify the specific risk level of stroke increased by a multiple interaction of metals, regression coefficients and odds ratio for a pair or multiple pair of metals were reanalyzed. However, all of regression coefficients and odds ratios were not significant. In conclusion, Co showed the significant level in blood from patients with stroke. In addition, the odds ratio of stroke was significantly different from other metals. Thus, it is considered that Co among various metals analyzed in this study is the important metal for increasing the risk of stroke.

• 한국환경보건학회지
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• 제36권2호
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• pp.155-162
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• 2010

Aflatoxin $B_1$, a known human carcinogen, is the member of aflatoxin subfamily that is most frequently found in contaminated foods. Epidemiological studies have suggested that aflatoxins may be associated with human liver cancer and acute hepatitis. Recently it was reported that the traditional medical herbs sold in domestic markets are contaminated with aflatoxins. Long-term administration of these contaminated medicines could result in adverse health effects. Therefore, it is important to evaluate the levels of exposure to aflatoxin in people who ingest traditional herbal medicines. Blood samples were collected, before and after the herbal medicine intake, from 151 subjects who visited the hospital. The metabolite of aflatoxin $B_1$ in blood, aflatoxin $B_1$-albumin (aflatoxin $B_1$-lysine), is reportedly an appropriate internal exposure indicator, and its levels in the collected bloods were therefore analyzed using a liquid chromatography-mass spectrometry. The analytical method of aflatoxin $B_1$-lysine in blood was firstly optimized in Korea and the levels were detected below quantification limits (2 pg/mg albumin) in this study population. Consequently, the exposure levels of aflatoxin $B_1$ by ingestion of herbal medicines were low but it is important to monitor routinely due to the possibility of risk on the aflatoxin exposure.

• Asian-Australasian Journal of Animal Sciences
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• 제28권12호
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• pp.1760-1766
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• 2015

This study investigated the proximate composition and $\small{L}$-carnitine and betaine content of meats from 5 lines of Korean indigenous chicken (KIC) for developing highly nutritious meat breeds with health benefits from the bioactive compounds such as $\small{L}$-carnitine and betaine in meat. In addition, the relevance of gender (male and female) and meat type (breast and thigh meat) was examined. A total of 595 F1 progeny (black [B], grey-brown [G], red-brown [R], white [W], and yellow-brown [Y]) from 70 full-sib families were used. The moisture, protein, fat, and ash contents of the meats were significantly affected by line, gender, and meat type (p<0.05). The males in line G and females in line B showed the highest protein and the lowest fat content of the meats. $\small{L}$-carnitine and betaine content showed effects of meat type, line, and gender (p<0.05). The highest $\small{L}$-carnitine content was found in breast and thigh meats from line Y in both genders. The breast meat from line G and the thigh meat from line R had the highest betaine content in males. The female breast and thigh meats showed the highest betaine content in line R. These data could be valuable for establishing selection strategies for developing highly nutritious chicken meat breeds in Korea.

• 전자공학회논문지
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• 제50권10호
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• pp.107-115
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• 2013

최근 RFID 기술은 u-헬스케어 서비스와 접목되어 의료서비스 분야에서 주목 받고 있는 추세이다. u-헬스케어 서비스는 개인 의료 정보를 다루는 분야로서 단순한 건강 검진 및 치료의 수준을 넘어 생명과도 밀접한 관계가 있다. 만약 개인 의료 정보가 불법적으로 노출되거나 악용될 경우 프라이버시 침해 뿐만아니라 생명까지도 위협받을 수 있으므로 보안성을 고려한 u-헬스케어 서비스 인증이 필수적으로 요구된다. 2012년에 Jeong 등은 RFID 기술을 이용하여 초기화 과정과 환자 인증 과정을 구분한 J-L 환자 인증 프로토콜을 제안하였다. Jeong등은 제안한 프로토콜에서 재사용 공격, 스푸핑 공격, 정보노출방지 및 불추적성에 대해 안전하다고 주장하였지만 보안성과 연산 효율성 문제를 발생시킨다. 따라서 본 논문에서는 Jeong 등이 제안한 프로토콜의 보안성과 연산 효율성 문제를 증명하고, 안전성과 효율성을 강화한 RFID 기술의 기반으로 하는 실용적인 u-헬스케어 서비스 인증 프로토콜을 제안한다.