• 한국컴퓨터정보학회논문지
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• 제22권9호
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• pp.81-89
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• 2017

The CRP(Container Relocation Problem) algorithms pursuing efficient container relocation of wharf container terminal can not be deterministic because of the large number of layout cases. Therefore, the CRP algorithms should adopt trial and error intuition and experimental heuristic techniques. And because the heuristic can not be best for all individual cases, it is necessary to find metrics which show excellent on average. In this study, we analyze GLAH(Greedy Look-ahead Heuristic) algorithm which is one of the recent researches in detail, and propose a heuristic metrics HOB(sum of the height differences between a badly placed container and the containers prohibited by the badly placed container) to improve the algorithm. The experimental results show that the improved algorithm, GLAH', exerts a stable performance increment of up to 3.8% in our test data, and as the layout size grows, the performance increment gap increases.

• 한국기계가공학회지
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• 제18권5호
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• pp.9-16
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• 2019

Recent economic trends are worsening and becoming longer, and Korean shipbuilding is focused on high value added and high technology, especially for LNG carriers and large container ships. Both ship types increased in size in the 2010s but have requirements such as high strength, toughness at low temperatures and continuous weldability for preventing brittle fractures at service temperatures. In particular, as container ships become larger, the International Classification Society (IACS) has established a provision (IACS UR S33) that mandates the use of BCA (Brittle Crack Arrest) certified vessels for large container vessels contracted after 2014 to ensure safety. Therefore, studies on BCA 47Y.P are currently being undertaken, but BCA 40Y.P has not been actively studied yet. We will test BCA 40Y.P to verify why it can be applied to a large container ship and measure fatigue cracking.

• Industrial Engineering and Management Systems
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• 제11권3호
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• pp.288-298
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• 2012

Lot sizing and shipment scheduling are two interrelated decisions made by a manufacturing plant and a third-party logistics distribution center. This paper analyzes a dynamic inbound ordering problem and shipment problem with a freight container cost, in which the order size of multiple products and single container type are simultaneously considered. In the problem, each ordered product placed in a period is immediately shipped by some freight containers in the period, and the total freight cost is proportional to the number of containers employed. It is assumed that the load size of each product is equal and backlogging is not allowed. The objective of this study is to simultaneously determine the lot-sizes and the shipment schedule that minimize the total costs, which consist of production cost, inventory holding cost, and freight cost. Because the problem is NP-hard, we propose three meta-heuristic algorithms: a simulated annealing algorithm, a genetic algorithm, and a new population-based evolutionary meta-heuristic called self-evolution algorithm. The performance of the meta-heuristic algorithms is compared with a local search heuristic proposed by the previous paper in terms of the average deviation from the optimal solution in small size problems and the average deviation from the best one among the replications of the meta-heuristic algorithms in large size problems.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2009년도 춘계학술발표논문집
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• pp.50-53
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• 2009

This paper proposes an object-oriented software development guidance and an evaluation index for the productivity related to spring framework 2.5. Non EJB and the EJB architecture to resolve the problem with benefits to support the new architecture is a lightweight container architecture. This architecture, such as the EJB, but not heavy, to provide all of the architecture is possible. The lightweight container architecture is most often used in business spring framework is well-known architecture. Therefore, this research has the Non EJB and the EJB to solve the advantages and disadvantages developed to support the latest spring framework 2.5 lightweight container architecture based on the design and implementation of a pilot system with the objective through the specification of the software previously to provide guidance to development productivity.

• 대한조선학회논문집
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• 제44권4호
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• pp.379-388
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• 2007

Ever increasing fuel prices and environmental concerns are forcing commercial vessel operators and designers to re-assess current vessel designs with an emphasis on their propulsion systems. The most important parameter determining propulsive efficiency is the diameter of propeller. Many investigations have been carried out to adapt a large and slow turning propeller known as one of the most robust and effective way of achieving high efficiency in ship propulsion system. However, for the same vessel a further increase of propeller diameter would require the modification of the aft end while still paying attention to the hull clearance to prevent excessive propeller excited vibrations. In order to take the advantage of this approach small workboats (e.g. tug boats, fishing vessels etc.) operate in service with a significant increase of aft draught and hence resulting "inclined keel" configuration can be observed. Although it is not unusual to see large vessels sometimes to operate with stern trim to improve their operational performance and fuel efficiency, it is rare to see a such vessel purposely built with an inclined keel feature to fit a large diameter propeller for power saving. This paper investigates the application of the inclined keel configuration to a 3600TEU container vessel with the aim of fitting an 11 % larger diameter propeller (and hence resulting 17.5 % lower rpm) to gain further power saving over the similar size basis container ship with conventional "level keel" configuration.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 춘계학술대회 논문집
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• pp.479-480
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• 2010

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2023년도 춘계학술대회
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• pp.121-122
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• 2023

컨테이너를 이용한 해상운송이 본격적으로 시작되면서 컨테이너선의 크기는 꾸준히 증가하고 있으며 최근에는 24,000TEU급 선박의 운항이 일반화되어 있다. 하지만, 최근 이러한 초대형 컨테이너 선박의 등장에 따른 효율성 및 생산성이 항만의 운영 관점에서 타당한지에 대한 의문도 지속적으로 제기되고 있다. 2022년 제10회 부산국제항만컨퍼런스에서는 글로벌 주요 정기선사들의 초대형 컨테이너 선박의 발주 현황을 분석하여 소강상태에 접어든 컨테이너 선박의 대형화 추세에 대한 심층적인 연구를 요구하였다. 일반적으로 선박 대형화 요인은 TEU당 운송 비용을 낮추는 규모의 경제 실현이며 이는 단일선박으로 대량의 화물을 수송함으로써 단위당 운송비용의 절감과 운송의 효율증가에 비해 연료 소모량의 증가가 낮아 단위당 운송비용의 절감 수준이 높아지기 때문이다. 하지만, 과연 항만의 측면에서 이러한 컨테이너 선박의 대형화 추세가 항만 운영에 있어서 타당성을 지니고 있는지에 대한 검토가 필요하다. 이를 위해 본 연구에서는 선형별 생산성 및 효율성을 비교·분석하여 항만 운영에 있어 선박 대형화의 효과를 평가한다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2023년도 추계학술대회
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• pp.72-73
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• 2023

컨테이너를 이용한 해상운송이 본격적으로 시작되면서 컨테이너선의 크기는 꾸준히 증가하고 있으며 최근에는 24,000TEU급 선박의 운항이 일반화되어 있다. 하지만, 최근 이러한 초대형 컨테이너 선박의 등장에 따른 효율성 및 생산성이 항만의 운영 관점에서 타당한지에 대한 의문도 지속적으로 제기되고 있다. 2022년 제10회 부산국제항만컨퍼런스에서는 글로벌 주요 정기선사들의 초대형 컨테이너 선박의 발주 현황을 분석하여 소강상태에 접어든 컨테이너 선박의 대형화 추세에 대한 심층적인 연구를 요구하였다. 일반적으로 선박 대형화 요인은 TEU당 운송 비용을 낮추는 규모의 경제 실현이며 이는 단일선박으로 대량의 화물을 수송함으로써 단위당 운송비용의 절감과 운송의 효율증가에 비해 연료 소모량의 증가가 낮아 단위당 운송비용의 절감 수준이 높아지기 때문이다. 하지만, 과연 항만의 측면에서 이러한 컨테이너 선박의 대형화 추세가 항만 운영에 있어서 타당성을 지니고 있는지에 대한 검토가 필요하다. 이를 위해 본 연구에서는 선형별 생산성 및 효율성을 비교·분석하여 항만 운영에 있어 선박 대형화의 효과를 평가한다.

• 한국시뮬레이션학회논문지
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• 제17권3호
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• pp.85-94
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• 2008

본 연구는 컨테이너 터미널에서 사용될 수 있는 교착방지를 위한 알고리즘 개발을 목표로 하였다. 기존의 교착방지 알고리즘은 많은 계산시간을 소요한다는 단점을 극복하기 위하여 본 연구에서는 하나의 경로에 대해서 예약스케줄을 작성하여 두고 반복적으로 사용하는 예약 스케줄 표 방식을 제안하였다. 시뮬레이션 실험 결과 예약 스케줄 표 방식은 그때그때의 주행경로에 대한 예약스케줄링을 위하여 계산시간이 필요 없기 때문에 AGV의 실시간 운영을 위하여 유용한 방식임을 알 수 있었다.

• 대한조선학회논문집
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• 제55권1호
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• pp.45-55
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• 2018

Concerns are emerging in marine industry on the additional fatigue damages induced by hydroelasticity, and large container carriers, among others, are considered to be susceptible to this hydroelastic response due to its large size, deck openings and high speed. This study focuses on the fatigue damage estimation of 9,400TEU container carrier based on the full scale measurement data via long-base strain gage installed on the ship. Some correlation analyses have been also done to check whether there was significant torsional response during the voyage. Direct cycle counting method was used to derive stress histogram and the long-term fatigue damage was estimated based upon that analyzed data. It turned out that the fatigue damage of this particular ship during the measurement period increased by more than 60% due to the hydroelastic response of the hull, and main contribution is considered to come from vertical bending mode.