• 조명전기설비학회논문지
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• 제23권6호
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• pp.104-108
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• 2009

본 논문에서는 지중전력케이블을 대상으로 케이블의 절연열화특성 분석시험을 통해 케이블의 절연열화와 절연 진단결과 및 파괴강도와의 상관관계에 대한 실증연구를 수행하였다. 시험대상 선로의 제조결함 여부를 확인하기 위해 가교도분석, 핫오일테스트 등을 실시한 결과 제조결함은 없는 것으로 확인되었다. 진단대상 선로는 3상 모두 장기간 사용에 의해 열화가 많이 진전되었고, 특히 B상이 수트리 길이 및 화학구조결함 농도 면에서 가장 열화된 케이블인 것으로 판단되며, C상, A상의 순으로 열화정도가 다소 감소함을 확인하였다. 상기 결과는 진단시험 및 파괴 강도시험 결과와 일치하며, 따라서 열화시정수법을 이용한 진단장치가 열화상태가 심각한 케이블의 선별에 효과적인 진단법임을 확인하였다.

• 한국염색가공학회지
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• 제8권3호
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• pp.8-15
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• 1996

Three pieces of cotton fabrics used for this study were exhumed in the Mt.Moo Deung near Kwang Ju in 1965. The fabrics were remains of Jang Heung Lim Si-the nephew's wife of General Kim Deok Ryeong. It was reported that Jang Heung Lim Si died in 1615. The cotton fabrics were classified into three, A, B and C, according to their color. The fabric A was inherent color of cotton, the fabric B was that of light brown and the fabric C was that of dark brown. The physical and chemical characteristics of the cotton fabrics were examined. In the meantime the construction of cotton fabrics and traditional dyeing of Yi dynasty were studied through various records. The results were as follows: 1. According to electromicroscopic examination, the lumen in the cotton fiber had not been developed enough, therefore the quality of cotton at that time was supposed to be not so excellent. 2. The results of chemical analysis indicated that: (1) While the copper number of the cotton fabric A was similar to that of bleached cotton, that of the fabric C was extremely high. (2) The amount of methylene blue absorption was much more than that of normal cotton. (3) The content of cellulose was less than that of normal cotton. (4) The degree of polymerization was less than that of normal cotton. From the results mentioned above, it was concluded that the cotton fabrics were oxidized slowly in the closed lime coffin for a long period of time. From this process of oxidization and deterioration, the degree of polymerization was decreased through depolymerization, and carboxyl groups were produced by the oxidization at reducing end groups. 3. It was confirmed that the cotton fabric C was dyed by the juice of immature persimmon. Thus, it was inferred that the large amount of copper number of cotton fabric C was derived from phenolic OH groups of tannins having high reducing properties in persimmon.

• 대한토목학회논문집
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• 제35권1호
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• pp.203-215
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• 2015

본 연구는 농촌지역의 쇠퇴도를 진단하고, 농촌생활권의 기초단위인 읍 면 지역에 대한 공간적 쇠퇴 특성과 유형을 도출하는데 목적을 두고 있다. 이를 위해, 충청권 27개 시 군을 대상으로 거시적 차원의 쇠퇴수준과 잠재수준을 분석하여 도시차원의 쇠퇴현상을 진단한다. 다음으로 공간단위를 세분화하여 충청권의 274개 읍 면지역을 대상으로 쇠퇴수준을 분석하고, K-평균군집분석을 적용하여 쇠퇴유형 및 쇠퇴특성을 도출한다. 충청권 시 군 별 쇠퇴수준 및 잠재수준 분석결과, 충남지역의 청양군, 서천군, 태안군이 높은 쇠퇴도를 보이고 있으며, 충북지역의 전통적 낙후지역인 남부 3군(보은, 옥천, 영동)과 단양군, 괴산군의 쇠퇴도가 높게 나타나고 있다. 또한, 충청권의 읍 면지역 중 쇠퇴의 경향을 보이는 166개 읍 면지역에 대한 군집분석 결과 인구 및 주택 노후화지역(29), 경제기반 취약지역(16), 중심지접근성 취약지역(42), 주거환경 열악지역(51), 노령인구 취약지역(28)의 5개 군집유형의 쇠퇴특성이 도출되었다. 충청권 농촌지역의 쇠퇴특성과 유형화를 시도한 본 연구는 농촌지역 활성화 정책 수립에 있어 기초자료로 활용될 것으로 기대되며, 향후 연구에서는 읍 면지역 차원을 넘어 농촌정체성의 기초단위가 되는 농촌마을을 대상으로 종합적인 진단과 맞춤형 정책발굴 연구가 이어질 것으로 기대된다.

• Structural Engineering and Mechanics
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• 제39권6호
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• pp.795-812
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• 2011

Estimation of damage probability of buildings under a future earthquake is an essential issue to ensure the seismic reliability. Fragility curves are useful tools for showing the probability of structural damage due to earthquakes as a function of ground motion indices. The purpose of this study is to compare the damage probability of R/C buildings with low and high level of strength and ductility through fragility analysis. Two different types of sample buildings have been considered which represent the building types mentioned above. The first one was designed according to TEC-2007 and the latter was designed according to TEC-1975. The pushover curves of sample buildings were obtained via pushover analyses. Using 60 ground motion records, nonlinear time-history analyses of equivalent single degree of freedom systems were performed using bilinear hysteretic model and peak-oriented hysteretic model with stiffness - strength deterioration for each scaled elastic spectral displacement. The damage measure is maximum inter-story drift ratio and each performance level considered in this study has an assumed limit value of damage measure. Discrete damage probabilities were calculated using statistical methods for each considered performance level and elastic spectral displacement. Consequently, continuous fragility curves have been constructed based on the lognormal distribution assumption. Furthermore, the effect of hysteresis model parameters on the damage probability is investigated.

• Journal of Electrical Engineering and Technology
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• 제10권1호
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• pp.344-354
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• 2015

In order to study the development of partial discharge (PD) under typical protrusion defects in gas-insulated switchgear, we applied step voltages on the defect and obtained the ${\varphi}-u$ and ${\varphi}-n$ spectrograms of ultra-high frequency (UHF) PD signals in various PD stages. Furthermore, we extracted seven kinds of features to characterize the degree of deterioration of insulation and analyzed their values, variation trends, and change rates. These characteristics were inconsistent with the development of PD. Hence, the differences of these features could describe the severity of PD. In addition, these characteristics could provide integrated characteristics regarding PD development and improve the reliability of PD severity assessment because these characteristics were extracted from different angles. To explain the variation laws of these seven kinds of parameters, we analyzed the relevant physical mechanism by considering the microphysical process of PD formation and development as well as the distortion effect generated by the space charges on the initial field. The relevant physical mechanism effectively allocated PD severity among these features for assessment, and the effectiveness and reliability of using these features to assess PD severity were proved by testing a large number of PD samples.

• 여성건강간호학회지
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• 제20권2호
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• pp.148-154
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• 2014

Purpose: This study was done to evaluate postoperative patient satisfaction, vaginal bleeding, and sexual function in women after laparoscopic supracervical hysterectomy (LSH). Methods: A retrospective study was conducted using a questionnaire mailed to 131 women who underwent LSH between 2008 and 2011at the Department of Obstetrics &Gynecology, D University Hospital in Chungnam province. Indication for LSH was uterine myoma. The questionnaire contained questions on overall postoperative satisfaction, influence on quality of life of vaginal bleeding, and sexual satisfaction following surgery. Data were collected from March to July 2013 and 109 (83.2%) patients returned the questionnaire. Results: Most women reported being very satisfied (90.8%) or satisfied (7.3%), but 2 women (1.8%) were not satisfied with LSH. Four patients (3.4%) reported experiencing vaginal bleeding but with no negative influence on quality of life. Of sexually active women, 82 patients (90.1%) reported improvements in sexual function, 8 patients (8.8%) reported "no change", and one patient (1.1%) reported a deterioration Conclusion: Results of this study indicate that LSH is associated with a high degree of patient satisfaction, no negative influence on quality of life from vaginal bleeding, and improvement in sexual function to a minimum 2 years after the procedure.

• 한국주거학회논문집
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• 제22권5호
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• pp.37-46
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• 2011

Residential space has come to maintain a degree of specialization dependent upon the division of space according to function, while roles and functions have either expanded or ceased to exist corresponding to shifts in social values. However, various human behaviors connected to lifestyle habits and values are in fact becoming obsolete. This research will examine the mental, social, and functional aspects of the relationship between residential work spaces in modern homes and the sarangche as well as the communal space of daily and social life of the Chosun Dynasty to enhance the value and function of traditional residential space. As the boundary between family and work blurs with the home office environment of today, we are experiencing a deterioration of health and seeing problems in securing family domain as well as the prolonging of overwork. While the function of the traditional sarangchae encompassed a wider variety of activities than today's homes, the sarangchae achieved an efficient use of space divisions between rooms according to the particular purpose and situation. Accordingly, a reinterpretation of modern residential work space is needed through its connection to the sarangchae with consideration to the philosophy and values of the life of the noble class and the habits of our traditional lifestyle that have previously taken place within the sarangchae in an exterior space.

• 동아시아식생활학회지
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• 제16권6호
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• pp.717-723
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• 2006

Chemical characteristics of soybean oil after deep-frying with potato sticks (200 g, 10% w/w of soybean oil) were studied according to the 34 deep-frying times. After consecutive 34 deep-frying, total polyunsaturated FA contents was gradually decreased while the total saturated FA and trans FA were increased. Acid value and peroxide value were increased while iodine value decreased, respectively. The Hunter $L^{\ast}$ value decreased while each $a^{\ast}\;and \;b^{\ast}b$ value were gradually increased. Electronic nose equipped with 12 metal oxide sensors was used for the discrimination of odor pattern of frying oils against the times of deep-trying. The proportions of 1st and 2nd principal component analysis showed 75.97% and 21.23%, respectively. While 6 among total 12 sensors well responded to discrimination of odor in the repented frying oils, suggesting that the odor pattern of each oil after deep-frying would be discriminated against fresh soybean oil, especially after 14 times. From the results, electronic nose could differentiate the degree of quality deterioration of the repeated deep-frying oils.

• 대한전기학회논문지:시스템및제어부문D
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• 제50권5호
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• pp.247-254
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• 2001

Silent period(SP) is transient stops of muscle activity that are induced by mechanical or electrical stimulus and the duration of silent period is a important parameter that have been associated with symptoms of masticatory dysfunction. Muscle fatigue is induced by sustained muscular contractions. It is associated with the external manifestations as the inability to maintain a desired force output, muscular tremor, and localized pain. Muscle fatigue is a parameter that have been measured or monitored the deterioration of a performance of muscles. On the study of relationship between SP and masticatory muscle fatigue, Nagasawa suggested that SP increases up to 3 min. from the beginning of clenching when the subjects performed sustained contractions at 50% maximum clenching level. In this paper, in order to evaluate a relationship between SP and muscle fatigue, 10 SPs per 1 minute are measured at 10%, 20%, 50% maximum clenching level. We used the median frequency in order to quantify the degree of muscle fatigue. However, the results shows that the duration of silent period was not significantly affected by differing levels of muscle fatigue. Therefore, we suggest that the SP is not increased or decreased as the results of muscle fatigue, also the origin of the SP generation mechanism is discussed.

• 대한토목학회논문집
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• 제11권4호
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• pp.9-15
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• 1991

본 연구는 도로교량들의 효율적인 안전도 명가 및 내하급수 판정 전산화 시스템을 개발하는데 그 목적이 있다. 이를 위해 현행 도로교 내하급수 체계를 합리적으로 개선한 후 외관조사 또는 가용 통계자료 만으로 안전성 평가를 실시할 수 있는 신뢰성 방법에 기초한 합리적인 내하력 평가방법을 제시하고 비상작전시 군용차량의 설제적인 허용통과 급수 판정시스템을 개발하였다. 연구결과 본 연구에서 제시된 내하력 및 내하급수 판정시스템, 그리고 내하력 평가 프로그램 BRS(Bridge Rating System)은 교량의 노후도와 각종 불확실량을 체계적으로 반영한 실 내하력 평가수단으로서 장차 교량의 안전성 및 내하력 평가에 널리 활용될 수 있다고 사료되었다.