• 한국환경생태학회지
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• 제26권5호
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• pp.827-834
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• 2012

본 연구는 백두대간권역의 설악산, 속리산국립공원 비개방 탐방로를 대상으로 탐방로 특성과 이용에 따른 영향을 파악하여 핵심지역 보전을 위한 공원관리와 비개방에 따른 이해 당사자들간의 갈등 해결을 위한 정책반영 기초자료 제시를 목적으로 하였다. 설악산국립공원 비개방 탐방로 3개 구간, 속리산국립공원 비개방 탐방로 1개 구간 총 17.1km, 112개 조사지점의 탐방로 특성을 조사한 결과 평균 노폭은 0.98m, 평균 나지폭은 0.84m, 평균 최대침식깊이와 종단경사는 각각 11.6cm, 14.2%이었다. 훼손유형 발생빈도는 뿌리노출이 53개소(47.3%)로 가장 많았으며 훼손영향이 적은 건전지점은 47지점(42.0%)이었다. 본 조사대상지는 산악형 국립공원의 개방 탐방로에 비해 훼손 압력은 적으나 국립공원을 일부 포함하는 다른 지역의 백두대간 마루금 탐방로와 비슷한 압력을 받고 있었다.

• 한국환경과학회지
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• 제24권11호
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• pp.1431-1442
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• 2015

This study was carried out to systematically maintain and manage the trails by assessing the physical characteristics, the types of deterioration and impact rating class of trails located in Mt. Nam District of the Gyeongju National Park. The major trails followed 6 routes including Sambulsa-Geumobong(A), Yongjangsaji-Geumobong(B), Yongjanggol-Yiyoungjae-Gowibong(C), Cheonusa-Gowibong(D), Sangseojang-Forest road(E) and Tongiljeon-Forest road(F). The routes length of A was 2.2 km, 2.7 km of B, 3.4 km of C, 1.3 km of D, 2.0 km of E and 1.0 km of F. In the physical characteristics, A was the widest and F was the narrowest in the width and bared width of trail. In depth of erosion, B was the deepest and E was the shallowest. D was the steepest and E was the gentlest in the slope. In the results of analysing the types of deterioration, A were 13 types, 11 types of B, C and D, 10 types of E and 6 types of F. The times of appearance of deterioration types in A were 86 times, 75 times of B, 105 times of C, 48 times of D, 47 times of E and 13 times of F. In case of the impact rating class, trail erosion was II degree, I degree of trail expansion, root exposure, trail divergence and rock exposure.

• 한국전기전자재료학회논문지
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• 제29권10호
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• pp.635-640
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• 2016

This paper dealt with the deterioration characteristics and an on-line diagnosis equipment for SPDs (surge protective devices). An accelerated aging test was carried out using a $8/20{\mu}s$ standard lightning impulse current to analyze the changes of electrical characteristics and to propose the diagnostic parameters and the criterion for deterioration of ZnO varistor which is the core component of SPDs. Based on the experimental results, an on-line diagnosis equipment for SPD was fabricated, which can measure the total leakage current, reference and clamping voltage. The leakage current measurement circuit was designed using a low-noise amplifier and a clamp type ZCT. A linear controller, the leakage current measurement part and a HVDC were used in the measurement of reference voltage. The measurement circuit of clamping voltage consisted of a surge generator and a coupling circuit. In a calibration process, measurement error of the prototype equipment was less than 3%.

• Journal of Advanced Marine Engineering and Technology
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• 제35권5호
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• pp.566-575
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• 2011

LPG 연료공급방식은 배출가스를 저감시킬 수 있는 유용한 시스템으로 연구가 지속적으로 진행되고 있다. LPG는 경유와 휘발유보다 높은 증기압과 낮은 점도와 표면장력을 유지하므로 고무류와 화학 반응에 따른 연료펌프의 기계적인 손상으로 내구성이 저하되고 있는 실정이다. 본 연구에서는 이러한 문제점을 해결하기 위해 LPLi 시스템에서 유지보수의 편리함과 가격경쟁을 위해 개발된 외장형 펌프를 사용하여 LPG 연료의 조성 및 온도에 따른 특성을 평가하고자 실험을 하였다. 그 결과로서, 내장형 펌프와 외장형 펌프의 성능차이는 거의 없으며 프로판 함유율이 높고, 연료온도가 높아짐에 따라 유량은 많아지나 펌프효율은 거의 차이가 없었다. 또한 LPG 자동차 연료공급장치의 특성상 연료조성 및 온도변화에 따른 차압도 거의 일정하게 나타내었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1829-1831
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• 2004

This paper described the capacitive sensor for the diagnosis of deterioration of electrical insulating oils applying guard-ring type the 3-terminal electrodes. To measure stable capacitance of the sensor and to determine the design factors of the sensor, we utilized computational analysis, FEM software. This capacitive sensor discern the extent of deterioration measuring relative permittivity of electrical insulating oils. The result of measuring numerous sample, mineral oils, as serviced year, we confirmed an increase in relative permittivity of oils. Moreover, we confirmed the superior characteristics of the sensor as a species, aged pattern of oils and operating temperature.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.128-130
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• 2000

This paper develops the deterioration detecting sensor in oil to monitor and diagnose oil-filled transformer more effectively. The on-line inspection of the oil-filled transformers used the temperature, the changes of the capacitance, the $tan{\delta}$ in oil. This sensor was designed based on the concentric cylindrical type so that it could be placed inside of the oil-filled transformer. And comparing to the existing system, it was proven to be appropriate. Establishment of the proposed sensor helps to build the confidence in monitoring of the oil-filled transformers.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.357-358
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• 2010

본 연구는 인공해수촉진열화시험에 의한 해양콘크리트의 내염특성 규명을 위한 연구의 일환으로서 시멘트 종류 및 도막처리에 따른 콘크리트의 특성을 분석하였으며, 시험 결과 강도 및 염소이온침투 특성 등을 고려할 경우 해양용 혼합시멘트가 콘크리트의 내염성능 개선에 효과적인 것으로 나타났다.

• 한국임상수의학회지
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• 제34권4호
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• pp.268-271
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• 2017

A 1.3 year-old Castrated male Bedlington terrier (10.0 kg of body weight) was presented with heart murmur and occasional coughing. Diagnostic imaging studies revealed supravalvular pulmonic stenosis (maximal velocity 2.91 m/s) from abnormal membranous structure (aperture) distal to the pulmonary valve in the main pulmonary artery. Further study also revealed pulmonic regurgitant (1.82 m/s of peak velocity, 13.2 mmHg of pressure gradient) jets started from the abnormal membranous structure. Since the dog had no obvious clinical signs related to heart failure, no interventional therapy including balloon dilation was considered in this case. Instead, medical treatment for preventing further deterioration of clinical signs related to PS was done with enalapril. This case report described a rare case of type III supravalvular PS in a dog, which has never been reported. Further deterioration of clinical signs has yet been recognized after medical treatment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기설비전문위원
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• pp.89-92
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• 2004

This paper described the capacitive sensor for the diagnosis of deterioration of electrical insulating oils applying guard-ring type the 3-terminal electrodes. To measure stable capacitance of the sensor and to determine the design factors of the sensor, we utilized computational analysis, FEM software. This capacitive sensor discern the extent of deterioration measuring relative permittivity of electrical insulating oils. The result of measuring numerous sample, mineral oils, as serviced year, we confirmed an increase in relative permittivity of oils. Moreover, we confirmed the superior characteristics of the sensor as a species, aged pattern of oils and operating temperature.

• 보존과학회지
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• 제36권4호
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• pp.236-243
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• 2020

In this study, an accelerated aging experiment for fabric and paper was conducted using two light emitting diode(LED) sources with different wavelength characteristics, and the discoloration under each lighting type was examined. Hanji(Korean traditional paper) and related textiles showed more discoloration under blue LEDs, while the blue wool standard showed more discoloration under white LEDs. This, indicated that the deterioration varied depending on the sample color. The the effect of the light source on artifact deterioration was primarily related to the total radiation flux(expressed in mill watts), rather than the total luminous flux(expressed in lumens). In addition, the discoloration of the investigated artifacts was dependent on the color rendering of the lighting.