• Title/Summary/Keyword: Minimal Dynamic-cost Path Search

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An Economic Ship Routing System Based on a Minimal Dynamic-cost Path Search Algorithm (최소동적비용 경로탐색 알고리즘 기반 선박경제운항시스템)

  • Joo, Sang-Yeon;Cho, Tae-Jeong;Cha, Jae-Mun;Yang, Jin-Ho;Kwon, Yung-Keun
    • KIPS Transactions on Computer and Communication Systems
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    • v.1 no.2
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    • pp.79-86
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    • 2012
  • An economic ship routing means to sail a ship with a goal of minimizing the fuel consumption by utilizing weather forecast information, and various such systems have been recently studied. For a successful economic ship routing system, an efficient algorithm is needed to search an optimal geographical path, and most of the previous systems were approaching to that problem through a minimal static-cost path search algorithm based on the Dijkstra algorithm. To apply that kind of search algorithm, the cost of every edge assigned with the estimated fuel consumption should be constant. However, that assumption is not practical at all considering that the actual fuel consumption is determined by the weather condition when the ship will pass the edge. To overcome such a limitation, we propose a new optimal ship routing system based on a minimal dynamic-cost path search algorithm by properly modifying the Dijkstra algorithm. In addition, we propose a method which efficiently reduces the search space by using the $A^*$ algorithm to decrease the running time. We compared our system with the shortest path-based sailing method over ten testing routes and observed that the former reduced the estimated fuel consumption than the latter by 2.36% on average and the maximum 4.82% with little difference of estimated time of arrival.

Economic Ship Routing System by a Path Search Algorithm Based on an Evolutionary Strategy (진화전략 기반 경로탐색 알고리즘을 활용한 선박경제운항시스템)

  • Bang, Se-Hwan;Kwon, Yung-Keun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.9
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    • pp.767-773
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    • 2014
  • An economic ship routing means to sail a ship with a goal of minimizing the fuel consumption by utilizing weather forecast information, and there have been various systems which have been recently studied. For a successful economic ship routing system, it is needed to properly control an engine power or change a geographical path considering weather forecast. An optimal geographical path is difficult to be determined, though, because it is a minimal dynamic-cost path search problem where the actual fuel consumption is dynamically variable by the weather condition when the ship will pass the area. In this paper, we propose an geographical path-search algorithm based on evolutionary strategy to efficiently search a good quality solution out of tremendous candidate solutions. We tested our approach with the shortest path-based sailing method over seven testing routes and observed that the former reduced the estimated fuel consumption than the latter by 1.82% on average and the maximum 2.49% with little difference of estimated time of arrival. In particular, we observed that our method can find a path to avoid bad weather through a case analysis.