• Title/Summary/Keyword: 요구운임률

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Optimum Structural Design of Tankers Using Multi-objective Optimization Technique (다목적함수 최적화기법을 이용한 유조선의 최적구조설계)

  • 신상훈;장창두;송하철
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.15 no.4
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    • pp.591-598
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    • 2002
  • In the ship structural design, the material cost of hull weight and the overall cost of construction processes should be minimized considering safety and reliability. In the past, minimum weight design has been mainly focused on reducing material cost and increasing dead weight reflect the interests of a ship's owner. But, in the past experience, the minimum weight design has been inevitably lead to increasing the construction cost. Therefore, it is necessary that the designer of ship structure should consider both structural weight and construction cost. In this point of view, multi-objective optimization technique is proposed to design the ship structure in this study. According to the proposed algorithm, the results of optimization were compared to the structural design of actual VLCC(Very Large Crude Oil Carrier). Objective functions were weight cost and construction cost of VLCC, and ES(Evolution Strategies), one of the stochastic search methods, was used as an optimization solver. For the scantlings of members and the estimations of objectives, classification rule was adopted for the longitudinal members, and the direct calculation method, GSDM(Generalized Slope Deflection Method), lot the transverse members. To choose the most economical design point among the results of Pareto optimal set, RFR(Required Freight Rate) was evaluated for each Pareto point, and compared to actual ship.

A study on increasing KTX operation efficiency of long-distant transportation methods in Korea (고속철도 운영효율성 분석)

  • Lee, Yon-Jai;Oh, Tae-Wan
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.1 no.2
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    • pp.225-253
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    • 2006
  • Last 1970's Korea opened the Kyoung-bu highways from Seoul to Pusan, and Korea government had change the transportation policy to focusing on the road and motors. but 1990's Korea had been the heavily traffic jam in long distant transportation system and logistics. That's why Korea government studied on feasibility survey of High-speed train. As the KTX opens, traffic networks covering large areas In Kyeongbu-line (Seoul- Daejeon- Busan) are expected to raise synergy effects in economics as well as in korean culture respects. Having been playing an important transportation role in Korea for the last 106 years. With opening of the high speed railway, KORAIL in inevitable to make a drastic reform. To achieve this purpose, it is necessary that KORAIL has to be small and effective streamlined organization. In should increase traffic capacity by improving infra facilities. It need to also expand its internal functions by connecting the KTX with the conventional railroad system.

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A study on increasing KTX operation efficiency of long-distant transportation methods in Korea (고속철도 운영효율성 분석)

  • Lee, Yon-Jai;Oh, Tae-Wan
    • 한국벤처창업학회:학술대회논문집
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    • 2007.04a
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    • pp.125-152
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    • 2007
  • Last 1970's Korea opened the Kyoung-bu highways from Seoul to Pusan, and Korea government had change the transportation policy to focusing on the road and motors. but 1990's Korea had been the heavily traffic jam in long distant transportation system and logistics. That's why Korea government studied on feasibility survey of High-speed train. As the KTX opens, traffic networks covering large areas in Kyeongbu-line(Seoul-Daejeon-Busan) are expected to raise synergy effects in economics as well as in korean culture respects. Having been playing an important transportation role in Korea for the last 106 years. With opening of the high speed railway, KORAIL in inevitable to make a drastic reform. To achieve this purpose, it is necessary that KORAIL bas to be small and effective streamlined organization. In should increase traffic capacity by improving infra facilities. It need to also expand its internal functions by connecting the KTX with the conventional railroad system.

  • PDF