• 제목/요약/키워드: Fleet

검색결과 357건 처리시간 0.026초

승객 수송 문제의 최적화 (Optimization of Passenger Transportation Problem)

  • 박준혁;김병인;김성배
    • 산업공학
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    • 제23권2호
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    • pp.139-146
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    • 2010
  • In this paper, we present the study of a real passenger transportation system. Passenger transportation problem aims to transport passengers from bus stops to their destinations by a fleet of vehicles while satisfying various constraints such as vehicle capacity, maximum allowable riding time in a bus, and time windows at destinations. Our problem also has special issues such as mixed loading, consideration of afternoon problem together with morning problem, and transferring passengers between vehicles. Our solution approach consists of three serial procedures: bus route generation, bus scheduling, and post optimization. Efficient heuristic algorithms were developed and implemented for the procedures. The proposed solution approach has been successfully applied to several real world problem instances and could reduce about 10% to 15% of buses.

2단계 수송네트워크 상에서의 장기적 비용 최적화 (A Cost Optimization Problem on a 2 Level Transportation Network)

  • 정재헌
    • 한국경영과학회지
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    • 제30권3호
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    • pp.1-15
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    • 2005
  • In our model, a fleet of vehicles start from docking point to collect loads at the terminals assigned to the point Then the docking points are connected to the hub by primary vehicle routes starting at the hub. This vehicle visit all the docking points to collect the loads which have been collected by the secondary vehicles. Our goal Is to minimize the long-run cost of setting up the docking Points and vehicle operation cost by deciding the location of the docking points and the routes optimally. We propose an heuristic algorithm to solve this and tested it though various experiments.

컨테이너 터미널 동적 운송 환경에서의 실시간 차량 운행 계획 (A Vehicle Dispatching for Dynamic Freight Transportation in Container Terminals)

  • 구평회;이운식;고시근
    • 한국경영과학회지
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    • 제30권3호
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    • pp.67-80
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    • 2005
  • This paper deals with a container terminal where containers are discharged by quay cranes from a ship and transported by a fleet of vehicles to the terminal yard. Since container terminals are fully utilized in general, It is important to increase terminal throughput by discharging the containers out of the ship without any delay, At the operational level, it should be decided which vehicle transports which container. The vehicle dispatching decision should be carefully made since the container discharging time increases when the quay cranes wait idle for the vehicles. This paper presents vehicle dispatching heuristics with the objective of minimizing the total container discharging time. The heuristics are based on a network flow model and a look-ahead concept. Through some experiments, the performance of the dispatching methods is evaluated.

Pulsed Field Gel Electrophoresis for Subtyping of Listeria monocytogenes

  • Jang, Sung-Sik;Fleet, Graham H.;Cox, Julian M.
    • Journal of Applied Biological Chemistry
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    • 제48권2호
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    • pp.58-64
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    • 2005
  • Listeria monocytogenes is a high-risk foodborne pathogen responsible for foodborne listeriosis outbreaks, and is particularly dangerous to immuno-compromised people with mortality rate of about 30%. This review summarizes subtyping of L. monocytogenes using Pulsed Field Gel Electrophoresis, widely used to trace origin of foodborne outbreaks and to determine relationship between isolates.

다양한 수송수단을 고려하는 (1:N) 공급체인에 대한 재고-수송의 통합계획수립 (Integrated inventory-distribution planning in a (1:N) supply chain system with heterogeneous vehicles incorporated)

  • 김은석;성창섭;양우석
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2006년도 추계학술대회
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    • pp.327-331
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    • 2006
  • This paper considers an integrated inventory-distribution system with a fleet of heterogeneous vehicles employed where a single warehouse distributes a single type of products to many spatially distributed retailers to satisfy their dynamic demands and the product is provided to the warehouse via procurement ordering from any manufacturing plant or market The Problem is formulated as an Mixed Integer Programming with the objective function of minimizing the sum of inventory holding cost (at the warehouse and retailers), and transportation cost and procurement ordering cost at the warehouse, subject to inventory-balancing constraints, ordering constraints, vehicle capacity constraints and transportation time constraints. The problem is Proven to be NP-hard. Accordingly, a Lagrangean heuristic procedure is derived and tested for its effectiveness through computational experiments with some numerical instances.

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해양플랜트 지원선박의 안전운항을 위한 법률 검토 (A Study on the Legal Review of Safety Operation for Offshore Supply Vessel)

  • 진호현;이창희
    • 수산해양교육연구
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    • 제27권1호
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    • pp.133-144
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    • 2015
  • Recently, Korea shipping companies have been internally/externally difficult to manage their fleet due to the high price of bunker, wage and low cost of charterage and freight. To solve these problems, some shipping companies have tried to set up a new business regarding offshore plant supply vessel(OSV). Owing to the absence of big oil field near the Korea coast, OSV market has not been gradually progressing as far. This study intends to review the legal review of both international and municipal law for the OSV. Therefore I have provided basic legal information to the domestic shipping companies which have desired to enter the OSV's market and suggest legal revision harmoniously to identify the problem in the municipal law.

FAST RADAR DATA PROCESSING FOR OIL SPILL DETECTION

  • Gershenzon, Olga N.;Gershenzon, Vladimir E.;Sonyushkin, Antony V.;Osheyko, Sergey V.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.985-988
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    • 2006
  • Oil spills cause huge material damage. Oil and oil products spills may occur at any stage of the offshore oil production and transportation cycle. Therefore taking into account the current trends of oil production, the task of creating a system for shelf and tank fleet monitoring becomes very crucial today. This document describes the technology being implemented to improve oil spill monitoring and surveillance, to ensure SAR data fast acquisition and processing and to develop geographic information systems in support of spill response decision making. The results of technology implementation are also presented below.

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항해수로 능력산정 모형 검토 (Navigational Channel Capacity Models)

  • 임진수
    • 대한교통학회지
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    • 제8권1호
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    • pp.5-15
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    • 1990
  • As a result of the lack of methodology for the determination of navigational channel capacity and the consequence lack of effective management of traffic, navigational channels are often grossly underutilized or highly congested. The traditional rule of first-come-first-served admission of vessels to channels is not efficient as it assumes equal time intervals between entrance of consecutive vessels. A new vessel traffic management system is developed in this research and methodologies to measure the improvement in the channel capacity are developed. Methodology to measure the channel performances for three queue disciplines are developed. The effects of changes in major factors on the channel capacity model such as channel length, fleet mix and arrival rate, as well as changes in strategy are analyzed. Under given channel conditions, best strategy are recommended. Also, a method for effective stochastic channel capacity simulation was developed. The results of analysis and as ertions are compared with the results of simulation runs to prove their applicability.

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유전알고리즘을 이용한 토사운반 최적경로 탐색 방법론 (Methodology for Selecting Optimal Earthmoving Haul-Routes using Genetic Algorithm)

  • 곽한성;이창용;이동은
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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    • pp.4-5
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    • 2014
  • Planning earthmoving haul-route must be preceded for appropriate equipment fleet assignment. However, traditional haul-route planning methods have limitations relative to practical usage because multiple variables (e.g., grade/rolling resistance, length, equipment's weight etc.) should be considered at a time. Genetic algorithm(GA) was introduced to improve these traditional methods. However, GA based haul-route planning method still remains in inefficiency relative to computation performance. This study presents a new haul-route searching method that computes an optimal haul-route using GA. The system prototype is developed by using MATLAB(ver. 2008b). The system identifies an optimal haul-route by considering equipment type, soil type, and soil condition.

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후진국의 해운산업 적성에 관한 연구 (Is Shipping a Poor Country's Business\ulcorner)

  • 민성규
    • 한국항해학회지
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    • 제3권2호
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    • pp.31-45
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    • 1979
  • The writer has attempted in the present article first to investiqate whether shipping industry is poor countries' business more favourable to them, compared to wealthy nations in terms of comparative cost of operation and to analyse how can developing conntries afford to maintain a modern fleet; secondly to examine the economic aspect of the situation created by the UNCTAD V held in May this year, at which passed a resolution demanding "the right of all countries to an equitable participation in the carriage of cargoes generated by their own trade"; and thirdly to adduce conclusions. The article contains six chapters; chapter I is the introduction on the subject under examination; chapter II provides background information on the structure of the industry and of the operating cost of ship; chapter III addresses itself to the legal backgrounds of ensuring free transfer of resources among nations and free competition of shipping; chapter IV deals with the recent development of shipping nationalism of developing countries at the UNCTAD; chapter V discusses division of labour in shipping and in particular the survival mechanism of high-cost countries; and chapter Ⅵ sets forth conclusion.onclusion.

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