• 제목/요약/키워드: Transportation Problem

검색결과 1,322건 처리시간 0.028초

Color Discerning Device의 구조해석을 통한 성능향상에 대한 연구 (A Study on Structural Analysis of Color Discerning Device for the Performance Enhance)

  • 김성현;이규호;정진태
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2006년도 추계학술대회논문집
    • /
    • pp.571-576
    • /
    • 2006
  • A Color Discerning Device(CDD) is the equipment to use in Rice Processing Complex(RPC). By use a high-speed charge-coupled device camera, CDD can sorting discolored grain according to light and shade. The existing CDD's driving performance is not so good as overseas machine. Besides, transportation process causes a defect in the mechanism from impact or harmonic excitation or etc. This study is represented the problem of CDD through modal analysis and static analysis by using ANSYS workbench. To analysis the problem of driving condition, devide each part of CDD for performed modal analysis. The problem of driving condition and transportation process solved by carry out modal analysis and static analysis.

  • PDF

수송 네트워크에서 최대물동량경로 문제의 최적해법 (An Optimal Algorithm for Maximum Origin Destination Flow Path in the Transportation Network)

  • 성기석;박순달
    • 한국경영과학회지
    • /
    • 제16권1호
    • /
    • pp.1-12
    • /
    • 1991
  • This paper studies an optimal algorithm for the Maximum Origin-Destination Flor Path (MODFP) in an acyclic transportation network. We define a Pseudo-Flow each are so that it can give an upper bound to the total flow of a given path. And using the K-th Shortest Path algorithm we obtain upper bound of MODF which is decreasing as the number of searched path grows. Computational Complexity of optimal algorithm is O(K + m) $n_{2}$), K being the total number of searched path. We proved that the problem complexity of finding MODFP in an acyclic network is NP-hard, showing that the-satisfiability problem can be polynomialy reduced to this problem. And we estimated the average of the number K as being (m/n)$^{1,08}$ Exp (0.00689gm) from the computational experiments.

  • PDF

군 수송기 운영 효율성 제고를 위한 최적경로 연구 (Effective Route Scheduling for Military Cargo-Plane Operation)

  • 김승기;이문걸;이현수
    • 경영과학
    • /
    • 제33권1호
    • /
    • pp.89-99
    • /
    • 2016
  • A scheduled airlift is the most critical part of the air transportation operations in ROK Air Force. The military cargo-plane routing problem is a PDPLS (pickup and delivery problem in which load splits and node revisits are allowed). The cargo which is transported by a military cargo-plane is measured in pallet. The efficiency of pallet needs to be considered with respect to its volume and weight. There are some guidelines about orders of priorities and regulations in the military air transportation. However, there are no methodologies which can raise the efficiency of flight scheduling using Operations Research (OR) theories. This research proposes the effective computing methodology and the related heuristic algorithms that can maximize the effectiveness of the path routing model.

동적 프로그래밍을 이용한 최적복합운송 알고리즘 (An Optimal Intermodal-Transport Algorithm using Dynamic Programming)

  • 조재형;김현수;최형림;박남규;김소연
    • 한국산업정보학회:학술대회논문집
    • /
    • 한국산업정보학회 2006년도 춘계 국제학술대회 논문집
    • /
    • pp.95-108
    • /
    • 2006
  • 본 논문은 수출입 컨테이너 화물의 국제물류에 대한 최적의 복합운송 경로를 도출하기 위한 동적 프로그램 알고리즘을 제시한다. 현재 3자물류 시장의 급부상, 운송업계의 경쟁가열화, 운송경로의 다양화 및 글로벌화가 추구되면서 복합운송을 고려한 수송계획의 효율화가 필요한 실정이다. 그러므로 2가지 이상의 운송수단을 이용하는 복합운송의 특징을 살펴보고, 운송비용과 운송시간을 고려한 WCSPP(Weighted Constrained Shortest Path Problem) 모형을 제시한다. 본 모형을 통해 도출된 목적함수 결과값을 이용하여 실행가능영역을 설정한 뒤, 동적 프로그래밍(Dynamic Programming)중 하나인 Label Setting 알고리즘을 응용하여, 두가지 목적함수를 동시에 만족할 수 있는 파레토 최적해를 도출하였다. 또한 본 알고리즘의 성능을 향상시키기 위해 가지치기 규칙을 함께 제안한다. 본 알고리즘을 부산에서 출발하여 로테르담까지 도착하는 실제 운송경로에 적용하였으며, 단일운송수단 및 기존의 복합운송 경로와 비교해 봄으로써 운송비용 및 운송시간의 절감효과를 정량적으로 측정하였다.

  • PDF

일간지를 통해 본 주거환경문제의 연구 ( II ) - 분뇨에서 변소의 정착과정을 중심으로 - (A Study of Housing Environment Problems through the Daily newspapers ( II ) -Centering around a excretion and fixing process of lavatory-)

  • 신경주
    • 한국주거학회논문집
    • /
    • 제3권2호
    • /
    • pp.89-99
    • /
    • 1992
  • We discussed the change of housing environmental problems from the early 1900s to the present in Study(I). This study(II) which secendly research of study(I) analyzed the fixing precess of a lavatory centering around a excretion which was a serious housing environmental problem in 1920 to 1940. The documentary research method was used for this study. Articles of content analysis(N=185) were published in 1920 to 1990 which were The Deng-A daily news article about a excretion and a lavatory. The main content of this study was examined the change, such as the number of whole article, the column number of article by time series. and the content of article by subject. 1. The number of whole article by time series was collected mainly in1920s-1930s. In 1940s-1960s, one-two column of article was appeared generally and three-four, five column of article was appeared in 1970-1980. 2. Contents of article was divided into two classes, excretion and lavatory. Contents of excretion was 1) a use of fertilizer 2) the method of transportation 3) a cost of gathering 4) a place of disposal 5) the problem of cleaning. Contents of lavatory was 1) a public lavatory 2) a flush toilet 3) a sanitary conditions 3. 1) A use of fertilizer was concentrated in 1920s-1930s, and problems of it was solved more or less by change of management method. Transportation of excretion developed such as \ulcornerGue\ulcorner->a coach of tank style->underground transportation->a dung car of absorption style. Disposal place of excretion was a cause of dissatisfaction in 1920s and it is serious problem Today. A duty of excretion gathering was transfered to a private worker in 1978. The accunulation problem of excretion was continued until 1940s-1950s. The management law of waste matters was proclaimed in 1986. 2) A public lavatory was planned in 1924 for the first time, and it is insufficient in these days, A settlement of public lavatory in building which has upward of 20pyung became obligation in 1973. The problem of water contamination which by poor septic tank was happened in 1970s-1980s.

  • PDF

GIS Buffering기법을 이용한 대중교통취약지구 선정방법 (Selection method of public transportation vulnerable area using GIS buffering analysis)

  • 김연웅;정성봉;장광우;박민규
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
    • /
    • pp.1739-1742
    • /
    • 2011
  • Public transportation network in our country is concentrated and advanced focusing on urban area in order to secure economic feasibility. As a result, as dependence on private vehicles is relatively getting higher in public transportation vulnerable area, traffic problem occurs since the average running speed in urban area is 22.5km/h. This paper has an objective to suggest an improvement plan by selecting public transportation vulnerable area, and defining according to urban structure, formation and function, and understand traffic characteristics and draw problems. As a method selecting public transportation vulnerable area, an area with high division rate of vehicle was selected as a primary proposed site by calculating division rate of means of public transportation according to area. Final proposed site was selected by using GIS Buffering technique aiming at selected proposed site, and selecting non-benefit area 500m outside, which is the road limit distance from each subway and bus station. Lastly, the degree of improvement effect was studied by constructing imaginary public transportation network aiming at final proposed site and comparing to the amount of change in division rate of means of transportation.

  • PDF

Space Syntax 기법의 대중교통망 적용 방안에 관한 연구 (Applying the Space Syntax Technique to the Network of Public Transportation)

  • 전철민
    • 대한공간정보학회지
    • /
    • 제12권2호
    • /
    • pp.73-77
    • /
    • 2004
  • 대도시의 도심 정체나 대중교통 장려책과 같은 요소로 인해 대중교통에 대한 관심과 이용도가 증가하고 있다. 그러나 노선의 설계나 배분에 관한 연구가 미흡하고 적절한 정량적인 방법론이 구축되어 있지 않기 때문에 설계, 운영에 어려움을 겪고 있다. 노선의 공급과잉이나 공급부족으로 인해 접근성이 지역간에 편중되어 나타나며, 도시 각 구역의 정류장은 다른 지역으로 이동하는 시간과 비용, 심적 부담에 있어 큰 편차를 보이고 있다. 한편, Space Syntax 이론은 도시공간이나 건축공간의 접근성을 공간의 기하학적인 연결구조에 기반하여 정량적으로 산출하는데 사용되는 이론이다. 본 연구는 Space Syntax 이론을 대중교통 문제에 효과적으로 적용하기 위해 알고리즘을 수정하였으며, GIS를 이용하여 간략한 가상의 네트워크를 구축한 후 이를 적용하는 과정을 예시하였다.

  • PDF

유전 알고리즘을 이용한 자동차 운반선사의 해상운송계획 (Maritime Transportation Planning of a Car Shipping Company using Genetic Algorithm)

  • 박병주;최형림;강무홍
    • 한국항해항만학회지
    • /
    • 제34권8호
    • /
    • pp.649-657
    • /
    • 2010
  • 자동차 운송선사들은 보다 많은 차량을 수송하고, 수송비용을 줄이기 위해서 보다 효율적인 운송계획을 통하여 자동차 운송선을 운용하고자 하지만 차량 해상운송 계획업무는 주로 실무자의 경험에 의존하여 수작업으로 이루어지고 있다. 해상운송은 국제 물류에서 차지하는 비중만큼이나 연구자의 높은 관심으로 다양하고 많은 연구들이 이루어져 왔지만, 자동차 운반선과 같이 해상운송 시장에서 작은 비중을 차지하는 경우에는 관심 부족으로 연구가 거의 이루어지지 못하였다. 이에 본 연구에서는 자동차 운반선사의 수작업 기반의 계획방식을 체계화된 알고리즘을 통해 최적의 해상운송 계획안을 제공할 수 있는 유전 알고리즘(genetic algorithm)을 제안하고, 제안된 알고리즘은 정수계획 모형으로 얻어진 최적해와 비교하여 평가한다.

우편 발송 비용 최소화를 위한 상업용 다량 우편물 선구분 적재 (Presort and Loading of Commercial Bulk Mails for Minimizing Mailing Fees)

  • 임승길;김재곤;신용호
    • 산업경영시스템학회지
    • /
    • 제36권1호
    • /
    • pp.8-16
    • /
    • 2013
  • We consider a problem of presort and loading of commercial bulk mails in a mailing service. Here, presort is the process by which a mailer prepares mail so that it is sorted to at least the finest extent required by the mailing service provider for the (discounted) price claimed. The problem is formulated as a special type of transportation problem. To solve industrial-sized problems, we develop an efficient heuristic algorithm and perform experimental tests on randomly generated problem instances. Results of the tests show that mailers can save mailing cost much more when they use small-sized mail trays with less frequent mailings. Also, large-sized mailers can obtain much more cost saving than small-sized mailers. In addition, cost saving effect is influenced by delivery area distribution of mails and fluctuation of mailing demand.

Distributed artificial capital market based planning in 3D multi-robot transportation

  • Akbarimajd, Adel;Simzan, Ghader
    • Advances in robotics research
    • /
    • 제1권2호
    • /
    • pp.171-183
    • /
    • 2014
  • Distributed planning and decision making can be beneficial from the robustness, adaptability and fault tolerance in multi-robot systems. Distributed mechanisms have not been employed in three dimensional transportation systems namely aerial and underwater environments. This paper presents a distributed cooperation mechanism on multi robot transportation problem in three dimensional environments. The cooperation mechanism is based on artificial capital market, a newly introduced market based negotiation protocol. In the proposed mechanism contributing in transportation task is defined as asset. Each robot is considered as an investor who decides if he is going to invest on some assets. The decision is made based on environmental constraint including fuel limitation and distances those are modeled as capital and cost. Simulations show effectiveness of the algorithm in terms of robustness, speed and adaptability.