• Corrosion Science and Technology
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• 제16권5호
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• pp.227-234
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• 2017

Reference electrodes are generally implemented for the purpose of monitoring the cathodic protection potentials of buried or immersed metallic structures. In the market, many types of reference electrodes are available for this purpose, such as saturated calomel, silver/silver chloride and copper/copper sulfate. These electrodes contain a porous ceramic junction plate situated in the cylindrical body bottom to permit ionic flux between the internal electrolyte (of the reference electrode) and the external electrolyte. In this work, the copper/copper sulfate reference electrode was modified by replacing the porous ceramic junction plate for a metallic platinum wire. The main purpose of this modification was to avoid the ion copper transport from coming from the inner reference electrode solution into the surrounding electrolyte, and to mitigate the copper plating on the coupon surfaces. Lab tests were performed in order to compare the performance of the two mentioned reference electrodes. We verified that the experimental errors associated with the measurements conducted with developed reference electrode would be negligible, as the platinum surface area exposed to the surrounding electrolyte and/or to the reference electrolyte are maintained as small as possible.

• 정보관리연구
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• 제30권1호
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• pp.29-47
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• 1999

컴퓨터시스템, 텔레커뮤니케이션, 정보 등 급속하게 발전하고 있는 핵심 정보기술의 발전양상과 이에 대비하기 위한 사서의 교육을 참고업무, 커뮤니케이션 기술, 경영을 중심으로 고찰하였다.

• 실천공학교육논문지
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• 제11권1호
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• pp.61-73
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• 2019

국내 평생직업능력개발 체계는 국가직무능력표준(NCS: National Competency Standards)을 중심으로 변화를 추진 중이다. NCS 중심의 직업훈련 체계가 성공적으로 정착하고 제 기능을 발휘하기 위해서는 고등교육의 중심인 4년제 대학에도 잘 적용되어야 한다. 그러나 4년제 대학의 경우 교과과정의 현장성 부재 문제가 지속적으로 제기되어 있고, 새롭게 출범한 대학연계형 일학습병행제 계약학과는 NCS기반의 자격을 교육과정의 중심에 두고 운영하도록 되어 있으나, 한국 기업의 현실을 고려한 표준모델의 부재로 인해 대학들이 신규 가입을 주저하고 있는 실정이다. 본 논문에서는 현재 운영 중인 코리아텍 일학습병행대학을 연구대상으로 하여 NCS기반 자격과 연계된 한국형 일학습병행대학의 표준모델을 개발하고, 이를 코리아텍 일학습병행대학 내 "기계설계공학과"에 실제 적용한 사례를 보인다. 또한 NCS기반 일학습병행대학 표준모델의 성공적 확산에 요구되는 다양한 시행방안을 관련 법 제도의 틀 안에서 도출하여 제시한다. 이러한 결과는 한국형 일학습병행대학의 확산을 촉진하고, 대학 및 기업의 참여동기를 제고하며, 궁극적으로는 NCS기반 일학습병행대학들이 평생직업능력개발의 한 축을 담당하는 데 크게 기여할 것으로 기대된다.

• Journal of Mechanical Science and Technology
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• 제17권1호
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• pp.77-84
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• 2003

Virtual work in multibody systems is frequently expressed as the inner product of the virtual displacement and the resultant force at the centroid. But provided that the resultant force is converted into the equipollent forces there is no restriction on where the analysis reference point is placed. There are basically three candidate points : the centroid, joint point and the instant global origin. The traditional fully recursive formulation uses the centroid, but the present work verifies that the instant global origin always shows better efficiency (e.g. 86% CPU time of the centroid for quarter car model) and joint point shows the efficiency between that of the centroid and the instant global origin. A discussion on how important it is to define the analysis reference point properly in a fully recursive formulation is also presented.

• 대한금속재료학회지
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• 제49권9호
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• pp.726-731
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• 2011

The present work shows how the flexural displacement-induced fracture strength of silicon devices, whose back surfaces have wafer grinding-induced scratch marks, depends on the crystallographic orientation. Experimental results indicate that silicon devices with scratch marks parallel to their lateral direction (i.e. reference axis in this work) are very susceptible to flexural fracture, as compared to devices with marks which deviated from the direction. The 3-point bending test shows that the fracture strength of silicon devices having marks which are oriented away from the reference axis is 2.6 times higher than that of devices with marks parallel to the axis. It was particularly interesting to see that silicon devices with identical preferred marks even reveal different fracture strengths, depending on whether the marks are involved in specific crystal planes such as {111} or {011}, called cleavage planes. This work demonstrates that silicon devices with the reference axis-aligned scratch marks not existing on such cleavage planes can have higher fracture strength approximately 20% higher than those existing on the planes.

• 정보관리학회지
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• 제19권4호
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• pp.214-231
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• 2002

본 연구는 디지털참고정보서비스의 최근 개발 동향을 고찰한 것이다. 디지털참고정보서비스와 관련한 국내외 선행 연구를 개관하였고 기술 개발로 인한 새로운 서비스 패러다임을 설명하였다. 그리고 웹 상의 참고정보서비스로서 도서관이 제공하는 것, 출판사에 의한 것, 전문가에 의한 것, 그리고 이용자 직접 탐색 등을 간략하게 열거하였다. 최근의 추세는 협력 모델이 주목을 받고 있으므로 Collaborative Digital Reference Service(CDRS)와 같은 디지털참고정보서비스 협력을 중점적으로 소개하였다. 도서관 전문직들은 디지털 환경에 적합한 참고정보서비스 협력에 관심을 가지고 그 필요성을 분석해야 할 것이다.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1723-1729
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• 2021

Energy and directional distribution of neutrons at the Beloyarsk NPP workplaces is a subject of this study. Measurements of H^*(10) rate and neutron energy distribution were taken at 8 workplaces, which can be divided into three categories: work with spent or fresh nuclear fuel, work with radionuclide neutron sources, work at the rooms adjusted to reactors. The Hp(10) measurements were performed only at 6 out of 8 locations, due to the fact that long term placing of an effective neutron moderator in fresh nuclear fuel storage facility is forbidden. As a result of the research energy and direction distribution of the neutron fields at 8 locations of the Beloyarsk NPP workplaces was obtained. To estimate the accuracy of the H^*(10) rate and Hp (10) measurements the reference values of dose equivalents were calculated using energy and directional distribution. To take into account the difference between the reference values and the measured results site-specific correction factors were calculated.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.43-44
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• 2010

We present the analysis of space geodetic technique observation, Satellite Laser Ranging (SLR), to LAGEOS1 and LAGEOS2 for the definition of the Terrestrial Reference Frame (TRF). The data were analyzed in 7day arcs during about 9 years (2000/01/10 ~ 2008/12/29) using NASA Goddard's GEODYN/SOLVE II software. The comparison of the coordinates between ITRF2005 and TRF solutions determined in this work shows that there is no significant bias.

• Nuclear Engineering and Technology
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• 제50권1호
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• pp.203-210
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• 2018

As the modernization of the nuclear instrumentation system progresses, research reactors have adopted digital wide-range neutron power measurement (DWRNPM) systems. These systems typically monitor the neutron flux across a range of over 10 decades. Because neutron detectors only measure the local neutron flux at their position, the local neutron flux must be converted to total reactor power through calibration, which involves mapping the local neutron flux level to a reference reactor power. Conventionally, the neutron power range is divided into smaller subranges because the neutron detector signal characteristics and the reference reactor power estimation methods are different for each subrange. Therefore, many factors should be considered when preparing the calibration procedure for DWRNPM channels. The main purpose of this work is to serve as a reference for performing the calibration of DWRNPM systems in research reactors. This work provides a comprehensive overview of the calibration of DWRNPM channels by describing the configuration of the DWRNPM system and by summarizing the theories of operation and the reference power estimation methods with their associated calibration procedure. The calibration procedure was actually performed during the commissioning of an open-pool type research reactor, and the results and experience are documented herein.

• 대한기계학회논문집A
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• 제28권6호
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• pp.701-708
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• 2004

This paper discusses applicability of the enhanced reference stress method to estimate J-integral along the semi-elliptical surface crack front. It is found that angular variations of normalized J­integral are strongly dependent on the geometry, loading mode and loading magnitude. As application of the reference stress approach to semi-elliptical surface cracks implies proportional increases in the normalized J-integral, the present results pose a question in applicability of the reference stress approach. However, investigation of the error in the estimated J-integral in the present work suggests that the enhanced reference stress approach, recently proposed by authors, provides an effective engineering tool fur estimating crack driving force along the semi-elliptical surface crack front.