• Corrosion Science and Technology
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• 제7권1호
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• pp.61-67
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• 2008

In this paper, electrochemical and microstructural characteristics of nickel-plated Alloy 600 were investigated in order to identify the performance of electroless Ni-plating on Alloy 600 in high-temperature aqueous condition with the comparison of electrolytic nickel-plating. For high temperature corrosion test of nickel-plated Alloy 600, specimens were exposed for 770 hours to typical PWR primary water condition. During the test, open circuit potentials (OCP's) of all specimens were measured using a reference electrode. Also, resistance to flow accelerated corrosion (FAC) test was examined in order to check the durability of plated layers in high-velocity flow environment at high temperature. After exposures to high flow rate aqueous condition, the integrity of surfaces was confirmed by using both scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). For the field application, a remote process for electroless nickel-plating was demonstrated using a plate specimen with narrow gap on a laboratory scale. Finally, a practical seal design was suggested for more convenient application.

• 대한안전경영과학회지
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• 제8권2호
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• pp.91-102
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• 2006

Korea Railroad Research Institute developed the driverless rubber-tired Korean-AGT system from 1999 to 2005 and has done its performance and reliability tests on the test line at Gyeongsan-city. We made the reliability management program to control required the RAMS(reliability, availability, maintainability & safety) of the K-AGT system. Therefore, we demonstrated the development and application of Reliability DB program. The main functions of K-AGT Reliability DB program manages failures and maintenance data systematically from the test line through test period and provides various analysis results based on the inputted data.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.994-1000
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• 2004

It is growing the application of the removal ground anchor with tension force for earth retaining constructions in the downtown. Nowadays, we can find the compression dispersion anchor on many site. But, it is occur some probelems in behabior of anchors because of impossible to tense p.c strand uniformly with existing equipment due to different length of p.c strand. So we tried to tense each p.c strand uniformly with auto back equipment in-situ test. This study compared and analyzed in-situ test results of an existing equipment with those of auto back equipment by appling elastic theory. As a result of the test, It has been proved that differences of tension force in the existing equipment increases with increasing the number of p.c strands. This can cause the ultimate failure of the concentrated p.c strand and the shear failure of ground. So it has been proved that auto back equipment is necessary.

• International Journal of Reliability and Applications
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• 제5권4호
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• pp.105-113
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• 2004

The exponential better (worse) than used EBU (EWU) class of life distributions is considered. A moment inequality is derived for EBU (EWU) distributions which demonstrate that if the mean life is finite, then all moments exist. Based on this inequality, a new test statistic for testing exponentiality against EBU (EWU) is introduced. It is shown that the proposed test is simple, enjoys good power and has high relative efficiency for some commonly used alternatives. Critical values are tabulated for sample sizes n = 5(1)40. A set of real data is used as a practical application of the proposed test in the medical science.

• 한국농공학회논문집
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• 제47권1호
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• pp.61-68
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• 2005

In this study, it was proposed that an equation for predicting consolidation settlement on soft clay ground, which separate total settlement into primary and secondary consolidation settlement equation. The consolidation settlements by the proposed equation and by the measured settlements from laboratory model test were compared and verified for its application. It was appeared that the proposed equation from the laboratory model test approach to be more realistic comparing to !the result of Terzaghi's equation. From the above application, it was concluded that the final settlement prediction by. the Hyperbolic, Asaoka methods is needed to the initial settlement but the proposed equation could be much applicable in the lacking condition of measured data of the initial period.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.325-330
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• 2008

LRT System Application Project is performed for the purpose of technical advancement and stabilization of K-AGT system from the viewpoint of practical use and commercialization. For those purpose, the performance test and evaluation procedure for K-AGT signaling system are developed, and the scheme of verifying the performance and function of signaling system under multi-train and driverless control environment is being conducted. For the multi-train operation in K-AGT test track, we applied the regenerative energy storage system in addition to the existing electric facilities. This paper present the design, manufacturing, and testing results of regenerative energy storage system.

• 한국초전도ㆍ저온공학회논문지
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• 제11권2호
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• pp.33-36
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• 2009

A 1 MW class HTS (High-Temperature Superconducting) synchronous motor has been developed. This motor is aimed to be utilized for industrial application such as large motors operating in large plants. The HTS field coil of the developed motor is cooled by way of neon thermo siphonmechanism and the stator (armature) coil is cooled by water through hollow copper conductor. This paper also describes evaluation of some electrical parameters from performance test results of our motor, which was conducted at steady state in generator mode and motor mode. Open and short circuit tests were conducted in generator mode while a 1.1 MW rated induction machine was rotating the HTS machine. Electrical parameters such as mutual inductance and synchronous inductance are deduced from these tests. Load test was done upto rating torque during motor mode and efficiency was measured at each load torque.

• 한국지반환경공학회 논문집
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• 제14권2호
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• pp.31-41
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• 2013

서해안 지역의 준설토는 실트 또는 세립모래 성분이 많은 특성으로 인해 성토재로 직접 사용되는 사례가 증가하고 있으나, 준설토를 성토재로써 활용하는 연구에 대해서는 미흡하다. 이에 본 연구에서는 서해안 지역의 준설토를 성토재료의 활용성을 확인 하고자 하였다. 우선적으로 피에조콘 관입시험을 통해서 준설 지반의 구성성분을 확인함으로써 성토재의 활용 가능성을 우선적으로 확인하였다. 준설토에 대한 침강 및 자중압밀시험을 시행하여 준설토의 특성을 평가하는 동시에 침강 및 자중압밀이 완료된 시료에 대해서 다짐시험 및 직접전단시험을 시행함으로써 준설토의 준설완료 시점의 특성을 확인하였다. 아울러 침강 및 자중압밀이 완료 된 시료를 자연배수시킴으로써 시간이 경과됨에 따라서 준설토가 보이는 역학적 특성을 확인하고자 하였다. 실트, 실트질 모래 및 모래성분이 다량 포함되고 있는 서해안 지역의 준설토는 자연배수 시간이 경과함에 따라서 단위중량과 전단강도가 증가되는 특성 을 보이는 것으로 평가되었다.

• 대한조선학회논문집
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• 제54권4호
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• pp.312-320
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• 2017

This paper deals with the development of structural test facility for the strength assessment of marine leisure boat built from carbon fiber reinforced plastics (CFRP) materials. The structural test facility consists of test jig, load application and control system, and data acquisition system. Test jig, and load application and control system are designed to accommodate various size and short span to depth ratios of single skin, top-hat stiffened and sandwich constructions in plated structural format such as square and rectangular shapes. A lateral pressure load, typical and important applied load condition to the plates of the hull structure for marine leisure boat, is simulated by employing a number of hydraulic cylinders operated automatically and manually. To examine and operate the structural test facility, five carbon/epoxy based FRP square plates having the test section area of $1m^2$, which are part of CFRP marine leisure boat hull, are prepared and they are subjected to monotonically increasing lateral pressure loads. In the test preparation, considering the symmetry of the plates geometry, various strain gauges and linear variable displacement transformer are used in conjunction with data acquisition system utilizing LabVIEW. From the test observation, the responses of the CFRP hull structure of marine leisure boat are understood by obtaining load to deflection and strain to load curves.

• 한국콘텐츠학회논문지
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• 제11권4호
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• pp.273-282
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• 2011

본 연구는 국소 허혈성 뇌손상 흰쥐 모델에서 tDCS의 자극 적용시간을 달리하였을 때, 앞다리 운동감각 기능변화와 신경영양인자(GAP-43)발현에 미치는 영향을 알아보고자 하였다. 뇌손상 모델은 Sprague -Dawley계 흰쥐 80마리를 'Longa'방법을 이용하여 중대뇌동맥(middle cerebral artery)을 폐색하여 유발하였고, 실험군을 4개로 나누었다; 실험군I은 허혈성 뇌손상 유발군(n=20), 실험군II는 허혈성 뇌손상 유발 후 tDCS(10분) 적용군(n=20), 실험군III은 허혈성 뇌손상 유발 후 tDCS(20분) 적용군(n=20), 실험군IV는 허혈성 뇌손상 유발 후 tDCS(30분) 적용군(n=20)으로 나누었다. 앞다리운동감각 기능검사를 위해 수정된 앞다리배치 검사와 단일 팰릿 닿기 검사를 실시하였으며, 신경가소성에 대한 면역조직화학적 검사로 운동감각 영역에서의 GAP-43 단백질 발현을 관찰하였다. 앞다리운동감각 검사는 14일에서 실험군III (p<0.05)이 다른 군들에 비해 유의한 차이를 보였으며, 단일 팰릿 닿기 검사는 14일에서 실험군III(p<0.01)과 실험군IV(p<0.05)에서 유의한 차이를 보였다. 또한, 면역조직학적 검사는 14일에 실험군III이 다른 군들에 비해 현저한 면역양성반응의 증가를 보였다. 따라서, 0.1 mA의 강도로 20분간 적용했을 때가 앞다리운동감각 기능과 신경가역성 인자 GAP-43 발현에 가장 좋은 조건임을 알 수 있었다.