• 제목/요약/키워드: Precedent Research

검색결과 467건 처리시간 0.033초

Effect of Silane and Sulfur Variation on the Vulcanizate Structure of Silica-Filled Styrene-Butadiene Rubber Compounds

  • Han, Sangwook;Kim, Donghyuk;Kim, Seongrae;Kim, Jongmyoung;Mun, Dalyong;Morita, Koichi;Kim, Wonho
    • Elastomers and Composites
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    • 제56권1호
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    • pp.32-42
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    • 2021
  • The vulcanizate structure of silica-filled compounds is affected by the filler-rubber interaction (FRI) due to the silica-rubber coupling reaction and the chemical crosslink density (CCD) of the matrix rubber. In this study, the vulcanizate structure changes of silica-filled compounds according to the silane and sulfur variation were quantitatively analyzed using the Flory-Rehner and Kraus equations. In efficiency vulcanization (EV) conditions with low sulfur content, FRI increased when the bis-[3-(triethoxysilyl)propyl]tetrasulfide (TESPT) content increased, and the CCD clearly decreased. By contrast, in semi-EV conditions with high sulfur content, as TESPT content increased, the FRI increased the same way EV conditions, but the CCD was unchanged. Based on these results, it was confirmed that FRI of the silica-filled compounds increased as TESPT content increased, but CCD decreased or retained similar values according to the vulcanization system, indicating that the formation reaction of FRI was preferred over CCD.

CONSTRUCTION COST INDEX FOR APPLYING INDEX ADJUSTMENT RATE IN THE ROAD PROJECT

  • Jin-Young Chun;Sungkwon Woo
    • 국제학술발표논문집
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    • The 1th International Conference on Construction Engineering and Project Management
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    • pp.1112-1117
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    • 2005
  • Construction cost index is generally used to estimate the new project cost based on past construction data and to adjust contract cost when the price change of various articles and items of expenditure composing the contract occurs. In Korea, it is mostly used for adjustment of construction contract cost due to fluctuation of prices. However index adjustment rate which is used for adjustment of construction contract cost had some problems in calculating cost index of each expenditure item that could not reflect properly the change of construction cost. For supplementing these problems, the research of developing construction cost index has been executed. Through the precedent research, these problems were partially resolved but still remain. Therefore this research proposes method of making cost index that utilizes representative items of labor, material, and equipment by analyzing bill of quantity of road construction, through analysis and comparison of precedent study. By using this method, it is expected to solve problems which were not reflected in precedent studies.

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개인 방탄·방검복 시스템 체계개발 선행연구 (A Precedent Research on Personal Armor and Anti-stab Wearing System Development)

  • 김훈;황태선;허영택;이창배
    • 한국기계기술학회지
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    • 제20권6호
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    • pp.879-885
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    • 2018
  • Precedent research and development of personal armor and anti-stab wearing system has been conducted since 2018 as a part of the government-affiliated cooperative development project to create the best utilization of present technology and achievement according to the civil and military technical cooperation project promotion law. At present, the armor system operated by the ROK(Republic of Korea) military, the police, and the marine police is utilizing only basic armor using armor vests and plates. Therefore it is necessary to develop the personal armor and anti-stab wearing system which is suitable for various tasks in army with maximum protection capability. In this paper, we analyzed the study about international technologies, market trends of the developed countries and scope of research, utilization plan, R&D results for the best armor and anti-stab wearing system development.

국방 선행연구단계에서 안전분석 기법에 기반한 수행프로세스의 개선 및 수행성숙도 평가를 활용한 위험 관리 (Safety Techniques-Based Improvement of Task Execution Process Followed by Execution Maturity-Based Risk Management in Precedent Research Stage of Defense R&D Programs)

  • 최세근;김영민;이재천
    • 한국산학기술학회논문지
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    • 제19권10호
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    • pp.89-100
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    • 2018
  • 방위력개선사업의 선행연구는 소요가 결정된 무기체계의 효율적 획득방법 결정을 지원하기 위해 수행되는 사업단계로, 선행연구단계에서 수행되어야할 요소를 식별하기 위해 안전분석 과정에서 활용되는 FTA/FMEA 기법의 수행방안을 착안 및 테일러링을 통해 핵심검토 항목 도출을 위한 방법론을 제시하였었다. 기존의 연구에서 도출한 핵심요소를 보완하기 위해 핵심요소로부터 발생 가능한 다양한 사건들을 추가 보완 및 분석이 필요했으며 이를 위해 타 산업분야에서 안전분석을 위해 수행하는 HAZOP 기법을 활용하여 핵심요소 도출결과를 보완하였다. HAZOP/FTA/FMEA 기법을 연계하여 도출된 선행연구단계의 핵심요소에 대해 입 출력 정보 및 연관관계를 설정하여 수행절차를 분석하고 모델화하였다. 또한 선행연구 수행성과에 대해 수행성숙도를 평가하고 성숙도가 낮은 핵심요소에 대해 관련 핵심요소와의 연동정보를 바탕으로 위험도 기반 대응 매뉴얼을 생성하였다. 본 연구결과를 토대로 방위력개선사업 선행연구단계에서 핵심요소 및 수행절차, 위험관리 대응 매뉴얼 적용을 통해 사업추진간 성능 비용 일정을 충족하고 예상되는 위험을 감소시켜 효율적이고 안정적인 방위력개서사업 추진을 기대할 수 있다.

관통형 연결재로 연결된 PC 보-기둥 맞댐 접합의 내진성능에 관한 실험적 연구 (Seismic Performance of Precast Beam-Column Joints with Thru-Connectors)

  • 박석준;박순규
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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    • pp.83-84
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    • 2010
  • 선행연구에서는 새로운 PC접합방식을 고안하여 실험을 실시하였다. 실험결과 비부착 긴장재의 특성 때문에 모든 실험체가 보 단부의 압축파괴 양상을 보였다. 따라서 본 연구는 압축력을 견디기 위하여 콘크리트 횡구속 보강근, 주근의 dog-boned를 변수로 실험체를 설계하였고, 더불어 향상된 내진성능을 확보하기 위한 목표로 실험연구를 수행하였다. 실험결과 주근 항복은 없었으며 횡구속 보강근의 영향으로 선행연구보다 내진성능이 우수한 것으로 나타났다.

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국방 선행연구단계에서 안전분석 기법 FTA/FMEA의 활용을 통한 핵심요소의 결정 (Determination of Key Elements Using FTA/FMEA Safety Techniques for Precedent Research Stage of Defense R&D Programs)

  • 최세근;김영민;이재천
    • 한국산학기술학회논문지
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    • 제19권9호
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    • pp.50-61
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    • 2018
  • 방위력개선사업의 선행연구는 소요가 결정된 무기체계의 효율적인 획득방법 결정을 지원하기 위해 사업초기 단계에 수행되고 있다. 사업 초기단계의 선행연구는 그 중요성이 간과되어 소홀히 진행되어 왔으며, 이로 인한 성능 미충족 및 비용증가 등의 사업추진간 문제점이 지속적으로 발생되고 있다. 제한된 시간내 많은 항목의 선행연구를 수행한 결과, 핵심검토항목을 깊이 있게 검토하지 못함으로써 사업추진간 예상되는 위험을 식별하고 감소시키는 역할을 제대로 수행하지 못하고 있다. 따라서, 본 논문에서는 방위력개선사업 선행연구 단계에서 수행시 고려해야 할 핵심요소들을 식별하기 위해 시스템안전 분석과정에서 사용되고 있는 FTA/FMEA 기법의 활용에 대해 연구하였다. 구체적으로 수행방안 도출시 FTA/FMEA 기법의 적용에 대한 착안점 및 주어진 조건에 부응하도록 개선을 통해 핵심검토 항목 도출을 위한 방법론을 구축하였다. 본 연구의 결과를 토대로 방위력개선사업 선행 연구단계에서 핵심 수행요소 재정립을 통해 향후 방위력 개선사업의 사업관리 측면에서 발생할 수 있는 불필요성 및 예상되는 위험을 제거함에 따라, 비용 및 시간을 절감하고 위험감소를 통한 사업의 안정적 추진을 기대할 수 있을 것으로 기대된다.

상법상 선장의 지위와 선박소유자의 대리권의 판례에 관한 연구 (A Study on legal status of shipmaster and precedent of his Authority)

  • 황석갑
    • 한국항해학회지
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    • 제17권3호
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    • pp.1-14
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    • 1993
  • The master of ship is always authorised to perform whatever acts are ordinarily necessary for the safe and proper prosecution of the voayge with regard to both ship and cargo. In other words, when a ship is away from her home port, where her business was managed, the master generally carried the owner's authority, and ordinarily he had power to enter into engagements, on their behalf, for carrying goods in the ship, or for letting her service, provided those engagements were consistent with the usual manner of employing her adopted by the owners. Accordingly he has always to decide onboard for an adequate applying of statutory law and cases whenever he acts. But the master would appear to have no such autho-rity where he can communicate with the owners without difficulty as, now-a-days, he nearly always can. This paper, therefore, intend to review some guidance of his authority in accordance with the Korean Code of Commerce as well as precedent based on it. The paper is also simply to place at the disposal of young shipmasters and those who aspire to command some legal information concerning limit of master's authority away from vessel's home port through legal commentation on the precedent, which may assist them to a better understanding of the many problems they may be faced with in the course of their ca-reers. In order to make an efficient study of legal structure concerned for shipmaster's authority, several up-to-date precedents are selected and described herein by writer's opinion for preventing unreasonable legal dispute in this field before courts in future.

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에코 패션디자인의 유형분석과 조형적 특성에 관한 연구 (A Study on Classification and Formative Characteristics of Eco Fashion Design)

  • 김새봄;이경희
    • 한국의류산업학회지
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    • 제12권5호
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    • pp.555-563
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    • 2010
  • This research has attempted for a categorization by contemplating on concepts and characteristics of eco fashion design through analysis of precedent studies and to study the design characteristics, images, and internal values through keyword and design codes which appeared in the precedent studies. The subject of analysis was mostly focused on the theses published in international and domestic academic journals from 1990s to September 2009. The design characteristics of each eco fashion design were analyzed by classifying by form, detail, color, fabric and pattern. Method of analysis did content analysis. The results of the research can be summarized as follows. First of all, types of eco fashion design were human-ecology design, natural-ecology design, and social-ecology design. Secondly, the human-ecology design was presented a natural and comfortable form, color of the nature, and functional and new materials. The natural-ecology design was presented a natural silhouette, natural colors, and natural fiber. The social-ecology design were used a loose silhouette and over-size forms, natural colors, and recycled materials and bio fabric. Thirdly, the images per type of eco fashion design were Zen, sportive, natural, and modern image. And the internal values were presented efficiency, health-orientation, naturalness, and continuity.

온라인 데이터베이스 이용자와 비이용자의 선행 정보탐색이 이용자 만족도에 미치는 영향 (A Study of the Precedent Information Search Patterns of On-line Database Users Compared to Non-users have an Effect on User Satisfaction)

  • 구연배
    • 한국문헌정보학회지
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    • 제41권1호
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    • pp.215-230
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    • 2007
  • 본 연구는 온라인 데이터베이스 이용자와 비이용자의 선행 정보탐색이 이용자 만족도에 끼치는 영향에 관하여 알아보기 위해 시도되었다. S대학 학생들의 도서관 시스템 이용 행태를 분석해봄으로써, 도서관의 정보서비스 및 시스템 점검과 효율성 측정 그리고 이용자 만족도를 높이기 위해 고려해야 할 사항들을 파악해보는데 목적이 있다. 그 결과 온라인 시스템을 이용하는 이용자가 이용하지 않는 이용자 보다 만족도가 높은 것으로 나타났다. 따라서 이용자들의 요구를 만족시키기 위하여 다양한 정보 접근점을 제공해야 할 것으로 생각된다.

도심 복합상업시설 공용공간의 보행자 지원적 환경계획에 관한 연구 (A Study on Environmental Plan To Support Pedestrians in Public Space of Urban Mixed-use Commercial Facilities)

  • 하미경;김아현;김숙하;이효창
    • 한국실내디자인학회논문집
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    • 제23권3호
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    • pp.181-192
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    • 2014
  • Recently, urban mixed-use commercial facilities have been required to raise a safe environment in public areas. So, this study focuses on analyze planning factors selected through the precedent research for Pedestrian safety and environment of urban mixed-use commercial facilities. The first purpose of this study is to analyse the applicative estimation of environmental plan to support pedestrians in public space of urban mixed-use commercial facilities in Seoul. And the second purpose of this study is to propose the directions of environmental planning for creating a pedestrian-friendly environment in public space of urban mixed-use commercial facilities. In order to accomplish this purpose, the environmental planning factors for supporting pedestrians and guidelines for disabled shown in the precedent studies are drawn. A survey of research subjects are 4 urban mixed-use commercial facilities located in downtown Seoul. And then a questionnaire survey is performed on architecture and interior design students to evaluate the importance. As a result of the study, the following conclusion are drawn. The pedestrian-friendly environment in urban mixed-use commercial facilities requires planning to strengthen accessibility, supporting and safety of public space.