• 한국안전학회지
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• 제30권6호
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• pp.164-173
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• 2015

There exists required safety integrity level (SIL) to assure safety in accordance with international standards for every electrical / electronics / control equipment or systems with safety related functions. The SIL is allocated from lowest level (level 0) to highest level (level 4). In order to guarantee certain safety level that is internationally acceptable, application of methodology for SIL allocation and demonstration based on related international standards is required. However, application standard differs from every industry in domestic or international for application on mythology for allocation and demonstration of SIL. Application or assessment is not easy since absence on clear criteria or common definition. This research studied not only fundamental concept of SIL required to guarantee safety in accordance with international standards for safety related equipment and system, but different types of methodologies for SIL allocation. Specifically, SIL allocation for Platform Screen Door system of railway is studied applying methodology of severity of accidents and risk graph among different methodologies for SIL allocation.

• 한국정보과학회논문지:데이타베이스
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• 제35권5호
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• pp.411-420
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• 2008

웹 환경에서 정보 표현과 교환을 위한 표준 방식으로 널리 사용되고 있는 XML 문서의 양은 급속히 증가하고 있으며, 대용량의 XML 문서도 많이 생산된다. 이러한 XML 문서들을 RDBMS에 효율적으로 저장하고 검색하는 연구가 활발히 진행되어 왔는데 이들 연구들 중에서 Shared Inlining 저장 방법이 높은 검색 효율을 보인다. Shared Inlining 방법은 DTD의 정보를 분석하여 XML 문서를 노드의 성분별로 분할하여 관계형 데이타베이스로 저장하는 기법이다. 본 논문은 기존의 Shared Inlining 방법에서 여러 하위 노드를 가지는 엘리먼트에서 발생되는 중첩 문제를 해결하기 위한 기법을 제안한다. 이 방법에서는 DTD 정의에 맞게 XML 문서를 Shared Inlining 구조로 저장하고 검색의 정확성을 높인다.

• Journal of Nutrition and Health
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• 제35권6호
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• pp.668-680
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• 2002

The purpose of this study was to investigation the importance and categorization of task elements of school food service dietician and to provide the useful data for standard model of the dietician′s tasks of school foodservice. This study was conducted in school food services nationwide in method of written questionnaire. The questionnaires were mailed to the dieticians of 3 type school foodservice system-conventional, commissary, joint management. Of the 660 schools that participated in this study, the responses from 212 conventional system and 212 commissary system and 200 joint management system were selected for analysis. Statistical analysis was performed with SAS/Win 6.12 package program for descriptive analysis, T-test, ANOVA, factor analysis using. The main results of this study can be summarized as follows Importance level was more than 4 score out of 5 scale in most of the task elements. The result was indicative of the appropriateness of definition of the 61 task elements. Of 61 task elements, importance level on ′nutrition education′ and on ′evaluation of foodservice operation management′ indicated the most significant difference between present and ideal situation. Through factor analysis, 61 task elements were regrouped into 7 dimensions; "Duty dimension of cooking and distribution management", "Duty dimension of cost management", "Duty dimension of raw material management", "Duty dimension of education management", "Duty dimension of menu management", "Duty dimension of record keeping of foodservice", "Duty dimension of general management (others)".

• 터널과지하공간
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• 제15권6호
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• pp.441-451
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• 2005

RMR 암반분류법은 구간별 RMR값 산정시 일정 범위의 값을 채택함으로 인해 불확정성을 피할 수 없다. 이에 본 연구에서는 각 파라미터별로 연속적인 RMR 값을 평가하여 확률밀도함수그래프를 산정하고 모든 경우의 수에 대한 몬테카를로 시뮬레이션과 통계추론을 통해 RMR 산정의 불확정성을 정량적으로 평가하였다. 또한 RMR 산정의 불확정성을 실무에 적용하기 위하여 신뢰수준별 수정 RMR 암반등급 산정표를 제시하였으며, 이를 근간으로 RMR 암반분류의 표준지보패턴 및 지보재 설계 수행절차를 제안하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권7호
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• pp.2874-2891
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• 2016

Due to its potential, the Internet of Things (IoT) begins to be used in the industrial field. Nevertheless, although the concept called the Industrial Internet of Things does not know a widely accepted definition, it is based on the existing technology, and introduces the IoT in the industrial environment through the compliance with specific additional requirements and by integrating various fieldbuses with distinctive features, from the real-time point of view. The aim of this paper is to propose a practical architecture for the Industrial Internet of Things. The proposed architecture is designed around the Data Distribution Service for Real Time System (DDS) middleware protocol, and it is organized on four levels. Between these levels, it is defined standard interface, and they can be developed independently. For this reason, the architecture is scalable because at the middleware level, the DDS can be replaced by other middleware systems. At the final, it is performed a comparison between several middleware systems used in the proposed architecture.

• 한국측량학회지
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• 제21권2호
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• pp.131-136
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• 2003

지형의 기복변화를 수치적으로 표현하는 수치표고모델에서 보간 기준점의 선정방법은 매우 중요하다. 하지만 아직까지 정확한 기준이 정해진 것 없이 사용자가 임의로 선정하여 보간을 수행하고 있는 실정이다. 본 연구에서는 수치표고모델을 보다 정확하고 효과적으로 구축하기 위한 보간 기준점 선정방법을 연구하였다. 점의 수를 적용한 선정 방법과 비정규적으로 분포되어 있는 점들을 정규 격자형태로 가정하고 구한 점들간의 평균거리를 적용한 기준점 선정 방법이 분석되었다. 그 결과 점들간 평균거리를 적용한 크리깅 방법이 수치표고모델을 구축하는데 보다 효과적인 방법임을 알 수 있었다.

• 한국과학교육학회지
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• 제11권1호
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• pp.59-72
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• 1991

This study has formed a clear definition of the elements of inquiry skills : inference, determining relationship, causal explanation, prediction, and created the goals of assessment and the items of assessment. They have been checked the validity and the objectivity and the clarity of the items by six professors of science education. At the same time, the two times of the field trial has been executed. and checked the discriminating power and the difficulty index and the effectiveness of distracters, and modified the items. The test developed in this way was administered to 1060 students of the eighth grade, randomly cluster-sampled from the universe, and standardized. The test is the aptitude test as well as the norm-reference test. and has twenty items. The testing-time is thirty minutes. And the cotent validity is 85%, the objectivity of the answer keys 91.7%, the mean of items difficulty 68.8%, the mean of discriminating power 0.39, the standard deviation 3.31, the reliability(K-R 20) 0.69. Because it is the standardized lest, it can diagnose the well-developed skills and the ill-developed skills of the students, and monitor the development of skills.

• 한국공간구조학회논문집
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• 제15권1호
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• pp.75-84
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• 2015

This paper presents the dimensionless wall distance, y+ effect on SST turbulent model for wind turbine blade. The National Renewable Energy Laboratory (NREL) Phase VI wind turbine was used for the study, which the wind tunnel and structural test data has publicly available. The near wall treatment and turbulent characteristics have important role for proper CFD simulation. Most of the CFD development in this area is focused on advanced turbulence model closures including second moment closure models, and so called Low-Reynolds (low-Re) number and two-layer turbulence models. However, in many cases CFD aerodynamic predictions based on these standard models still show a large degree of uncertainty, which can be attributed to the use of the $\epsilon$-equation as the turbulence scale equation and the associated limitations of the near wall treatment. The present paper demonstrates the y+ definition effect on SST (Shear Stress Transport) turbulent model with advanced automatic near wall treatment model and Gamma theta transitional model for transition from lamina to turbulent flow using commercial ANSYS-CFX. In all cases the SST model shows to be superior, as it gives more accurate predictions and is less sensitive to grid variations.

• 한국비블리아학회지
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• 제14권2호
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• pp.159-178
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• 2003

본 연구는 대학도서관에서 제공하는 전자게시판 중 자유게시판, Q＆A, FAQ, 참고질의 응답의 4가지 유형의 참고서비스를 대상으로 게재되는 질문의 유형과 내용을 분석함으로써 서비스 유형별 특성을 조사하고 이용자의 정보요구를 파악하였다. 분석한 결과, 4가지 서비스의 유형에 따라 질문유형별 차이를 발견하지 못하였다. 모든 서비스에서 안내형 질문이 가장 많았으며, 주제형 질문은 미미한 것으로 나타났다. 분석결과를 토대로 4가지 유형별 서비스에 대한 발전방안을 제시하였다: 서비스 유형에 대한 메뉴명칭의 표준화, 서비스 접근이 용이한 메뉴 배치, 각 서비스에 적합한 성격 명시, 내용검색기능과 응답기능을 첨가하는 구조개선, 질문작성 양식의 제안, 전자참고서비스의 전담부서 및 전담자배치, 정책마련, 홍보강화를 제안하였다.

• Computers and Concrete
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• 제1권2호
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• pp.211-226
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• 2004

A relatively simple multiple-vertical-line-element macro model has been incorporated into a standard computer code DRAIN-2D. It was used in blind predictions of seismic response of cantilever RC walls subjected to a series of consequent earthquakes on a shaking table. The model was able to predict predominantly flexural response with relative success. It was able to predict the stiffness and the strength of the pre-cracked specimen and time-history response of the highly nonlinear wall as well as to simulate the shift of the neutral axis and corresponding varying axial force in the cantilever wall. However, failing to identify the rupture of some brittle reinforcement in the third test, the model was not able to predict post-critical, near collapse behaviour during the subsequent response to two stronger earthquakes. The analysed macro model seems to be appropriate for global analyses of complex building structures with RC structural walls subjected to moderate/strong earthquakes. However, it cannot, by definition, be used in refined research analyses monitoring local behaviour in the post critical region.