• Journal of Korea Water Resources Association
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• v.55 no.6
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• pp.405-419
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• 2022

Flood frequency analysis commonly used to design the hydraulic structures to minimize flood damage includes uncertainty. Therefore, the most appropriate design flood within a uncertainty should be selected in the final stage of a hydraulic structure, but related studies were rarely carried out. The total expected cost function introduced into the flood frequency analysis is a new approach for determining the optimal design flood. This procedure has been used as UNCODE (UNcertainty COmpliant DEsign), but the application has not yet been introduced in South Korea. This study introduced the mathematical procedure of UNCODE and calculated the optimal design flood using the annual maximum inflow of hydroelectric dams located in the Bukhan River system and results were compared with that of the existing flood frequency. The parameter uncertainty was considered in the total expected cost function using the Gumbel and the GEV distribution, and the Metropolis-Hastings algorithm was used to sample the parameters. In this study, cost function and damage function were assumed to be a first-order linear function. It was found that the medians of the optimal design flood for 4 Hydroelectric dams, 2 probability distributions, and 2 return periods were calculated to be somewhat larger than the design flood by the existing flood frequency analysis. In the future, it is needed to develop the practical approximated procedure to UNCODE.

• Construction Engineering and Management
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• v.4 no.4 s.16
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• pp.58-64
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• 2003

건설 프로젝트를 수행함에 있어서 사업관리운영 절차서는 매우 중요하다. 국내에서는 일부 대형 공공 사업을 제외하고 프로젝트의 특성에 맞는 절차서를 개발하여 적용한 예는 드물다. 이러한 점을고려하여 현재 공사가 진행죽인 대표적인 국내민간자본 SOC사업을 표본으로 삼아 절차서의 활용현황을 검토분석하고 그에 따른 효율화 방안을 구하여 보았다. 이를 위해서 사업수행주체인 발주자, 사업관리자, 감리자, 설계자, 시공계약자 등을 대상으로 현재 보유/사용하고 있는 절차서에 대한 이해도, 사업관리지식체별 업무절차에 대한 이해도를 설문조사하였다. 설문조사의 분석결과를 토대로 건설사업관리수행상 업무수행절차의 전반적인 이행실태를 점검하여 문제점을 도출함으로서 향후 사업관리운영절차서의 체계적인 개발을 위한 추진방향을 설정하고 사업관리전반에 대한 인식제고와 효율적인 사업관리체계의 적용방안을 모색하여 제시하였다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.2
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• pp.115-121
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• 2015

The objective of this study is to present the design approach of low $CO_2$ concrete structures for reduction of $CO_2$ emissions. The design approach was implemented considering the system boundary for each processing presented in the ISO 13315-2. As for life-cycle inventory(LCI) for $CO_2$ assessment of concrete structures, data provided from domestic LCI DB was used. Based on the process presented in this study, case studies on the life-cycle $CO_2$ assessment of shear wall concrete structure was conducted. As substitution level of GGBS is 25%, the amount of $CO_2$ emissions and $CO_2$ uptake by concrete carbonation was decreased in the material, demolition and crushing, and transport phase. The amount of $CO_2$ emissions of column and total member was decreased by 26% and 22% respectively, compared to that of OPC.

• Aerospace Engineering and Technology
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• v.11 no.2
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• pp.33-38
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• 2012

A LEO Satellite performs automatic initial operations by FSW after separation from a launch vehicle. After initial operation by FSW is finished, preparation for normal operation is performed by ground during bus initial activation and checkout phase. First of all, we check state of health of the satellite including solar array deployment status. After then, each unit of spacecraft bus is activated and checked. After activation and checkout of every units used for normal operation, we check maneuver performance for imaging mission and orbit maintenance performance. Because the Bus IAC is performed during limited ground contact time, every detailed procedure must be designed considering ground contact. Therefore, the Bus IAC procedure is separated into several parts based on ground contact duration. In addition, the procedures for every possible operation including expected situation as results of IAC procedures and unexpected contingency situation must be prepared. The contingency operation is also designed based on ground contact duration. The LEO satellite was successfully launched and the Bus IAC was successfully performed. In this paper, we explain design concepts and execution results of Bus IAC.

• Computational Structural Engineering
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• v.17 no.3
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• pp.14-21
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• 2004

MDO프레임웍은 설계 작업을 통합적으로 관리하고 자동화하여 설계도구 간의 데이터 전달과 변환에 소요되는 설계자의 부담을 경감시키며 다분야 전문가가 참여하는 협동설계 환경을 제공함으로써 다분야를 동시에 고려한 효율적 설계를 지원한다. 이번 글에서는 이러한 MDO프레임웍으로 개발된 EMDIOS를 소개하고, 그 개발 배경과 타당성을 개략적으로 제시하였다. EMDIOS는 분산 환경을 제공하고, 데이터베이스와 연계되어 정의된 문제와 문제 풀이 절차를 저장하고 실행시 발생하는 데이터들을 체계적으로 관리하는 구조를 갖는다. MDO문제 해결에 필요한 도구들은 모두 소프트웨어 컴포넌트로 구성 및 기술되어 컴포넌트 등록기에 등록되어 저장된다. 등록된 컴포넌트는 GUI기반의 MDO커널에 의하여 검색되고 MDO문제해결 절차의 구성 요소가 된다. 구성된 문제 해결을 위한 실행은 컴포넌트 서비스 에이전트에 의하여 이루어진다. EMDIOS는 새로운 설계도구를 EMDIOS에 쉽게 통합하여 사용할 수 있도록 공통적으로 구현될 수 있는 부분을 구현한 추상 클래스와 이로부터 필요한 인터페이스를 생성할 수 있는 인터페이스 제조기를 제공함으로써 확장성과 개방성을 제공한다. 제시된 MDO 프레임웍의 사용자 인터페이스는 가장 많은 사용자를 확보하고 있는 윈도우 환경에서 Visual C++를 이용하여 개발되고 있으며, 다양한 OS환경에서 작동되어야 하는 래퍼는 JAVA로 개발하였다. 현재 개발된 EMDIOS는 다양한 벤치 마크 테스트 중이며 올해 9월이후에는 일반에게도 공개할 수 있는 프레임웍으로써 모습을 갖출 것으로 보인다.

• Journal of the Korean Society for information Management
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• v.25 no.4
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• pp.347-361
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• 2008

This study is to present cooperative instructional concept framework for the library-based instruction of teacher-librarians, based on 'Information and the Library' curriculum and instructional design procedure. The development of cooperative instructional units has been initiated in the school libraries, but the research based on instructional theories, including instructional design, is lacking. In this aspect, instructional theories and methodologies for the cooperative instruction of teacher-librarians are important. The cooperative instructional units for teacher-librarians should be developed by 'Information and the Library' curriculum and instructional design procedures. The objectives of the curriculum emphasize information use process based on information task. This study is to present cooperative instructional concept framework, and to help teacher-librarians develop specific cooperative instructional units based on the framework.

• Fire Science and Engineering
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• v.32 no.1
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• pp.24-32
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• 2018

There are two kinds of method on hydraulic calculation of fire sprinkler system design. The one is using the computational program and the other is designer calculate system for oneself. In case of using the computational program, putting the input data in, the program calculate the friction loss, water flow, total height and so forth. If program user or designer doesn't know the basic idea and procedure of hydraulic calculation. Then, the outputs are different from each other. This paper suggests the hydraulic calculation procedure in design area as follow. Equivalent lengths of tees on the branch are selected base on the same pipe diameter which the tees are established, although the diameter of tee outlet is different. Even though there is a different friction loss of head from the other head, the pressure from the hydraulic end is bigger than a head loss, discharge flow is calculated by pressure from the hydraulic end.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.405-408
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• 2008

It is increased concerns that review the design based on the economic efficiency, VE(Value Engineering), in construction industry. Also, the effectiveness of VE case study has reported very variously in the domestic and foreign construction industry. The phase of drawing idea VE process is important because of real cost saving effect. The design review checklist in the phase of drawing idea make more effective VE. The research suggests the method and process of design review checklist focusing on the construction work in this study. Also, it proposes the useful process with the exited VE procedure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.479-488
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• 2019

The flight test operational procedure artifact includes mission planning, execution methods, and safety measures for each step of test progress. As the development of guided missiles has become more advanced and strategic, flight test has become increasingly complex and broadened. Therefore, increased reliability of the flight test operation procedures was required to ensure test safety. Particularly, the design of the flight test operational procedures required verification through M&S to predict and prepare for the uncertainty in a new test. The relevant studies have published the optimal framework development for flight tests and the model-based improvements of flight test processes, but they lacked the specificity to be applied directly to the flight test operational procedures. In addition, the flight test operational procedures, which consist of document bases, have caused problems such as limitations of analysis capabilities, insensitive expressions, and lack of scalability for the behavior and performance analysis of test resources. To improve these problems, this paper proposes how to design operational procedure of guided missile flight test system by applying MBSE(Model-based Systems Engineering). This research has improved reliability by increasing the ability to analyze the behavior and performance of test resources, and increased efficiency with the scalability applicable to multiple flight tests. That can be also used continuously for the guided missile flight tests that will be developed in the future.

• Computational Structural Engineering
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• v.3 no.3
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• pp.39-47
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• 1990

본 고에서는 현재 국내 원전설계시 원용되고 있는 미국의 원전내진설계 관련규준의 구성체계를 훑어본 다음, 최근 대폭 개정된 절차를 중심으로 그 배경 및 세부내용을 소개하고, 이들 개정내용이 설계결과에 미칠 영향을 분석하고자 한다.