• 한국해양공학회지
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• 제13권3B호
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• pp.116-126
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• 1999

The purpose of this study is to analyze the economic aspect of sea transportation system between Inchon and Youngjong island in which Inchon international airport is being constructed. Total demand of sea transportation arising from in the airport and Yongyu Muwi leisure complex was estimated. To select optimum transportation route, environmental conditions in and around Inchon harbour and Youngjong island including the change of water depth by tide current, fog, rain, wind adn typhoon, ets., were investigated. The preliminary consideration on ships (size, velocity, transport capacity, price), routes, operational modes, terminals and berthing facilities were carried out. The transportation cost per passenger by sea transportation system was estimated to compare with that of land transportation system. It was found that sea transportation system proposed is competitive to the transportation system.

• 전자공학회논문지
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• 제53권11호
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• pp.166-174
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• 2016

본 논문에서는 스포츠 이벤트에서 선수단 수송 계획을 위한 혼합 정수 선형 계획법 모델을 제안하였다. 선수단 수송 계획은 선수단을 다수의 숙소에서 경기장까지 최소의 비용과 빠른 시간 계획을 찾는 것이다. 운행 회수를 의사결정 변수로 하고, 전체 수송비용은 최소가 되어야 하는 목적함수가 된다. 제안한 방법은 혼합 정수 선형 계획법을 이용하여 전역 최적점을 찾을 수 있는 장점이 있다. 제안한 방식의 유용성을 확인하기 위해서 시뮬레이션을 수행하고 스포츠 이벤트 관리 서비스 플랫폼(SEMSP)에서 수송 계획을 구축하였다.

• 산업경영시스템학회지
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• 제26권1호
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• pp.85-94
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• 2003

In this paper, a mathematical model is developed for economic design of multi-stage distribution system that consists of factory, central distribution centers, local distribution centers and retailers. The retailers are supplied products from different stage suppliers according to order size. The retailers are supplied products from factory if demand amount is large, central distribution center if medium, local distribution center if small. The economic design is to determine the economic size of facility factors that consist of distribution system. The cost factors are transportation cost from supply places to demand places, handling cost at distribution centers and inventory holding cost at retailers. It is to determine the transportation route of each retailer, the size and number of the vehicle at factory and distribution centers, the handling amount at distribution centers in order to minimize the total costs. The mathematical model is represented, the solution procedure is developed, and a numerical example is shown.

• 한국경영과학회지
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• 제3권1호
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• pp.69-73
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• 1978

This paper deals with the problem of determining the optimal inventory-transportation policy of the idealistically simple inventory-transportation system with the following assumptions: (1) The system consists of a single central warehouse and a single local warehouse, (2) The planning horizon is finite, (3) Demand rate is fixed costant, and so forth. Developed is the algorithm by which to identify the optimal inventory policy which minimizes the total cost incurred to the system over the given finite planning horizon. A sample numerical example is presented along with a discussion of the possible applications of the approach used n the algorithm.

• 한국항만학회지
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• 제3권1호
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• pp.3-33
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• 1989

The amount of the Korean export & import in 1987 reached $88.3 billion which was 1.75% of the total world trade and the proportion of foreign dependence to G.N.P was 74.5%. From these facts, we can infer that the development of national economy is largely dependent upon trade. Therefore the role of transportation, especially Ocean transportation, as a basis of economic development through trade is one of the main factors that can not be passed over. Here, We can define that a port as a subsystem of transportation determines the efficiency of the total transportation system. Thus, the purpose of this paper is to contribute in improvement of the efficiency in port, reinforcement of the international competitiveness for exporting goods by the analysis of the cargo handling charges. In order to do this, this paper deals the case of B.C.T.O.C. Furthermore, this study gives some important informations related to the level of tariffs for establishing an autonomous port administration. The Summary of the conclusions of this paper is as follows ; 1) The object of port administration in Korea has been emphasized on the maximization of efficiency in using the port facilities. Nowadays, however, it should be moved to a direction that port is operated under the compound aims considering the public interests and economy. 2) For a criterian of tariff calculation, A tariff system based on the cost accounting is desirable. In general it is recommended that the cost for construction, management, and operation of port is compensated by the revenue from port operation. Therefore, it is necessary for the administration bodies of each port to establish a tariff system on the basis of the independent profit system. 3) For the investigation of actors of tariff adjustment by the Break-even point analysis, (1) When we conducted the B.E.P analysis using total cost as cost term, we got 3.8% discount in tariff at 12% of target profit rate and 1.5% discount at 15% of rate. when we set the target profit rate as 17% we could have the proper tariff level. (2) When using operating cost as cost term, we got 13.1% discount in tariff at 12% of target profit rate and 10.9% discount at 15% of rate. When setting the target profit rat as 28%, we could have the proper tariff level. 4) Comparing with the tariffs of foreign ports for the basic terminal rate, The tariff level of B.C.T.O.C showed 33% of stevedoring charge and 80% of marshalling charge incurred at Kobe port. The comparison with Singapore port gave 50% of transhipment charge and 17% - 20 % of stevedoring charge. 5) We found that the financial structure of B.C.T.O.C was better than those of other companies and the worth fixed assets ratio was too low. The fact of low worth fixed assets ratio implies that the cargo handling facilities should be increased. Moreover, The return of assets for B.T.T.O.C was good but non-operating expenses were still contained too much in. Therefore, we think that it is necessary for B.C.T.O.C. to rationalize business management. Although the present cargo handing charge for B.C.T.O.C is a proper level in terms of a public corporation, for the final recommendation in connection to the results, It is required to take the rationalization process for business management.

• 대한교통학회지
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• 제20권2호
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• pp.27-38
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• 2002

1999년 설날 연휴기간중 고속도로의 교통혼잡비용을 경부구간 한 방향 운행 차량(설날 전의 귀성차량과 설날 이후의 귀경차량)을 대상으로 추정하였다. 추정에 앞서 명절 고속도로 혼잡은 수요의 비탄력성과 초혼잡의 특성을 가지나 전통적인 혼잡비용 추정방법을 적용할 수 있음을 보였다. 추정 결과 연휴 5일 기간 중 평균 주행 속도는 귀향 첫날 시속 18.8km로 가장 느렸고, 경부구간 전체 주행에 총 18시간이 소요된 것으로 나타났다. 정상소통시의 기준속도로 주행할 경우의 소요시간 5.6시간에 비해 무려 12.4시간이 더 걸린 것이다. 연휴 기간에 이 구간 통행 차량의 혼잡비용은 약 448억원으로 추정되었다. 혼잡비용의 내용 면에서는 시간 지체로 인한 시간 비용이 대부분을 차지했으며, 유류 비용이나 환경오염 비용은 상대적으로 적었다.

• Korean Chemical Engineering Research
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• 제53권2호
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• pp.164-173
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• 2015

본 연구에서는 다양한 도로운송부문용 에너지 공급 시스템을 구축하고 각 시나리오의 최적 비용을 비교분석하였다. 에너지 공급 시스템의 구성요소로써 기존의 정유공정, 부생수소 시스템, 신재생 에너지 자원 기반의 전력 생산공정, 전력운송을 위한 전력망을 설정하였으며, 내연기관자동차, 전기자동차, 연료전지자동차 등 세 가지의 도로운송부문용 자동차를 포함하였다. 이러한 구성요소를 포함한 다양한 에너지 공급 시스템 시나리오를 기반으로 최적 생애주기비용을 규명할 수 있는 에너지 시스템 평가모델을 개발하였다. 본 연구에서 개발한 최적화 모델을 제주도 지역에 적용함으로써 모델의 성능을 검증하였고 또한 제주도 지역의 에너지 시스템 구축에 관한 다양한 시나리오의 경제성을 분석하였다. 제주도 도로운송부문용 에너지 공급 시스템의 생애주기비용 분석 결과, 전력망을 이용하여 전기를 공급하는 전기자동차 시나리오가 상대적으로 가장 높은 경제성을 보였으며, 신재생 에너지 자원을 이용하여 수소를 공급하는 연료전지자동차 시나리오가 가장 낮은 경제성을 보였다. 또한 연료비용, 차량비용, 인프라비용, 유지비용 등 주요 비용 관련 변수들에 관한 민감도분석을 수행함으로써 생애주기비용의 변화에 주요한 구성요소들을 규명하였다.

• 산업공학
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• 제20권2호
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• pp.103-111
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• 2007

A heterogeneous VRP which considers various capacities, fixed and variable costs was suggested in this study. The transportation cost for vehicle is composed of its fixed and variable costs incurred proportionately to the travel distance. The main objective is to minimize the total sum of transportation costs. A mathematical programming model was suggested for this purpose and it gives an optimal solution by using OPL-STUDIO (ILOG CPLEX). A genetic algorithm which considers improvement of an initial solution, new fitness function with weighted cost and distance rates, and flexible mutation rate for escaping local solution was also suggested. The suggested algorithm was compared with the results of a tabu search and sweeping method by Taillard and Lee, respectively. The suggested algorithm gives better solutions rather than existing algorithms.

• 대한교통학회지
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• 제27권3호
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• pp.49-58
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• 2009

대전시를 사례로 위계수준을 달리한 4개의 노선망 대안(대안 1은 위계가 없는 노선망, 대안 2, 대안 3, 대안 4는 각각 초급, 중급, 상급 수준의 위계를 가진 노선망)을 작성하고, 평가지표(차내통행시간비용, 대기시간비용, 환승페널티비용)를 산출하여 대안간 비교를 통해 효율성을 분석하였다. 차내통행시간비용은 위계가 높은 대안일수록 감소하다가 위계가 매우 높아지면 다시 증가하는 것으로나타났다. 대기시간 비용은 위계가 높은 대안일수록 큰폭으로 감소하며, 환승페널티비용은 위계가 높은 대안일수록 증가하는 것으로 나타났다. 종합적으로 볼 때 총통행비용은 위계가 있는 노선망이 위계가 없는 노선망에 비하여 낮은 것으로 나타나 위계구조를 가진 노선망의 효율성이 높은 것으로 나타났다. 위계가 있는 노선망 중에서는 위계가 높을수록 총통행비용이 감소하다가 위계가 지나치게 높아지게 되면 오히려 증가하는 특성을 보임으로써 중급수준의 위계를 가진 노선망이 가장 효율성이 높은 것으로 분석되었다.

• 대한산업공학회지
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• 제27권2호
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• pp.140-149
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• 2001

The paper discusses the problem of finding the Origin-Destination(O-D) shortest paths in internodal transportation networks with time-schedule constraints. The shortest path problem on the internodal transportation network is concerned with finding a path with minimum distance, time, or cost from an origin to a destination using all possible transportation modalities. The time-schedule constraint requires that the departure time to travel from a transfer station to another node takes place only at one of pre-specified departure times. The scheduled departure times at the transfer station are the times when the passengers are allowed to leave the station to another node using the relative transportation modality. Therefore, the total time of a path in an internodal transportation network subject to time-schedule constraints includes traveling time and transfer waiting time. In this paper, a genetic algorithm (GA) approach is developed to deal with this problem. The effectiveness of the GA approach is evaluated using several test problems.