• 제목/요약/키워드: transportation algorithm

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Design of Intelligent Transportation Control System Based on Blockchain Technology

  • Xia, Wei
    • Journal of Information Processing Systems
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    • 제18권6호
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    • pp.763-769
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    • 2022
  • Transportation allocation requires information such as storage location and order information. In order to guarantee the safe transmission and real-time sharing of information in all links, an intelligent transportation control system based on blockchain technology is designed. Firstly, the technical architecture of intelligent transportation information traceability blockchain and the overall architecture of intelligent transportation control system were designed. Secondly, the transportation management demand module and storage demand management module were designed, and the control process of each module was given. Then, the type of intelligent transportation vehicle was defined, the objective function of intelligent transportation control was designed, and the objective function of intelligent transportation control was constructed. Finally, the intelligent transportation control was realized by genetic algorithm. It was found that when the transportation order volume was 50×103, and the CPU occupancy of the designed system was only 11.8%. The reliability attenuation of the code deletion scheme was lower, indicating better performance of the designed system.

수송문제의 최적해 (Optimal Solution for Transportation Problems)

  • 이상운
    • 한국인터넷방송통신학회논문지
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    • 제13권2호
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    • pp.93-102
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    • 2013
  • 본 논문은 수송 문제의 최적 해를 찾는 방법을 제안하였다. 수송 문제는 공급량과 요구량이 동일한 균형 수송과 공급량과 요구량이 다른 불균형 문제로 구분된다. 수송문제의 최적 해를 얻는 대표적인 TSM은 먼저, 불균형 수송 문제인 경우 가상의 행이나 열을 추가하여 균형 수송 문제로 변환시킨다. 다음으로 NCM, LCM, VAM 등 다양한 방법을 적용하여 초기 해를 구한다. 마지막으로 초기 해가 최적 해인지 검증하는 MODI를 적용한다. 따라서 최적 해를 구하는 과정이 복잡하다. 제안된 방법은 불균형을 균형 수송 문제로 변환하는 과정을 거치지 않고 직접 적용한다. 또한, 초기 해가 최적해인지 검증하는 과정도 수행하지 않는다. 제안된 방법은 첫 번째로, 행에 대해 공급량을 비용 오름차순으로 요구량을 만족하도록 배정한다. 두 번째로, 각 열에 대해 배정된 량이 요구량을 초과하는 순으로 배정량을 조정한다. 배정량 조정 방법은 다음 수행 순위 열의 비용과의 차이인 손실비용이 가장 큰 셀에 우선 배정하고 나머지 셀에 대해서는 배정량을 조정한다. 조정된 배정량은 요구량을 만족하지 못하는 수행 순위 오름차순 셀들에 추가된다. 모든 열에 대해 배정량이 조정되면 마지막으로 행의 최소 비용에 미 배정되었거나 열의 최대 비용에 배정된 경우 배정량을 상호 교환하는 방법으로 추가 조정한다. 불균형 배송 2개와 균형 배송 13개 데이터에 제안된 방법을 적용한 결과 모두 최적 해를 구하는데 성공하였다. 또한, 기존의 방법들이 최적해를 구하지 못한 4개 데이터에 대해서 추가로 최적 해를 구하였다. 따라서 제안된 방법은 수송 문제에 대해 일반화된 단일 방법으로 적용할 수 있을 것이다.

인공신경망과 유전 알고리즘을 이용한 팩맨 게임 강화학습 (Pacman Game Reinforcement Learning Using Artificial Neural-network and Genetic Algorithm)

  • 박진수;이호정;황두연;조수선
    • 대한임베디드공학회논문지
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    • 제15권5호
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    • pp.261-268
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    • 2020
  • Genetic algorithms find the optimal solution by mimicking the evolution of natural organisms. In this study, the genetic algorithm was used to enable Pac-Man's reinforcement learning, and a simulator to observe the evolutionary process was implemented. The purpose of this paper is to reinforce the learning of the Pacman AI of the simulator, and utilize genetic algorithm and artificial neural network as the method. In particular, by building a low-power artificial neural network and applying it to a genetic algorithm, it was intended to increase the possibility of implementation in a low-power embedded system.

A Network Capacity Model for Multimodal Freight Transportation Systems

  • Park, Min-Young;Kim, Yong-Jin
    • 한국항만경제학회지
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    • 제22권1호
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    • pp.175-198
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    • 2006
  • This paper presents a network capacity model that can be used as an analytical tool for strategic planning and resource allocation for multimodal transportation systems. In the context of freight transportation, the multimodal network capacity problem (MNCP) is formulated as a mathematical model of nonlinear bi-level optimization problem. Given network configuration and freight demand for multiple origin-destination pairs, the MNCP model is designed to determine the maximum flow that the network can accommodate. To solve the MNCP, a heuristic solution algorithm is developed on the basis of a linear approximation method. A hypothetical exercise shows that the MNCP model and solution algorithm can be successfully implemented and applied to not only estimate the capacity of multimodal network, but also to identify the capacity gaps over all individual facilities in the network, including intermodal facilities. Transportation agencies and planners would benefit from the MNCP model in identifying investment priorities and thus developing sustainable transportation systems in a manner that considers all feasible modes as well as low-cost capacity improvements.

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운송 문제의 최소비용 우선 배정 알고리즘을 적용한 총괄계획 (Aggregate Planning Using Least Cost First Assignment Algorithm of Transportation Problem)

  • 이상운
    • 한국인터넷방송통신학회논문지
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    • 제21권5호
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    • pp.181-188
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    • 2021
  • 총괄생산계획을 작성하는데 있어 운송법은 일반적으로 운송문제에 특화된 NCM, LCM, VAM 중 어느 하나로 초기 해를 구하고 SSM, MODI 중 어느 하나로 최적화를 수행하는 TSM에 대해 선형계획법 소프트웨어 패키지를 활용하고 있다. 반면에, 본 논문에서는 소프트웨어 패키지 도움 없이도 총괄생산계획을 쉽고 빠르며, 정확하게 작성하는 운송법을 제안한다. 제안된 알고리즘은 단순히 최소비용 우선 배정법을 적용하고, 재고기간을 최소화하는 방법을 제안하였다. 제안된 알고리즘을 6개의 실험데이터에 적용한 결과 VAM이나 LP에 비해 4개 데이터에 대해서는 보다 좋은 결과를, 나머지 2개 데이터에 대해서는 동일한 결과를 얻었다.

고정비용 수송문제를 위한 효율적인 진화 알고리듬 (An Efficient Evolutionary Algorithm for the Fixed Charge Transportation Problem)

  • 석상문;장석철;이상욱;안병하
    • 대한산업공학회지
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    • 제31권1호
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    • pp.79-86
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    • 2005
  • The transportation problem (TP) is one of the traditional optimization problems. Unlike the TP, the fixed charge transportation problem (FCTP) cannot be solved using polynomial time algorithms. So, finding solutions for the FCTP is a well-known NP-complete problem involving an importance in a transportation network design. So, it seems to be natural to use evolutionary algorithms for solving FCTP. And many evolutionary algorithms have tackled this problem and shown good performance. This paper introduces an efficient evolutionary algorithm for the FCTP. The proposed algorithm can always generate feasible solutions without any repair process using the random key representation. Especially, it can guide the search toward the basic solution. Finally, we performed comparisons with the previous results known on the benchmark instances and could confirm the superiority of the proposed algorithm.

트랜스포터의 공주행(空走行) 최소화를 고려한 블록 운반 계획 최적화 (Optimal Block Transportation Scheduling Considering the Minimization of the Travel Distance without Overload of a Transporter)

  • 임선빈;노명일;차주환;이규열
    • 대한조선학회논문집
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    • 제45권6호
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    • pp.646-655
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    • 2008
  • A main issue about production management of shipyards is to efficiently manage the work in process and logistics. However, so far the management of a transporter for moving building blocks has not been efficiently performed. To solve the issues, optimal block transporting scheduling system is developed for minimizing of the travel distance without overload of a transporter. To implement the developed system, a hybrid optimization algorithm for an optimal block transportation scheduling is proposed by combining the genetic algorithm and the ant algorithm. Finally, to evaluate the applicability of the developed system, it is applied to a block transportation scheduling problem of shipyards. The result shows that the developed system can generate the optimal block transportation scheduling of a transporter which minimizes the travel distance without overload of the transporter.

최적 경로 알고리즘들의 계산비용 비교 및 트랜스포터의 최적 블록 운송 계획 적용 (Comparison of Optimal Path Algorithms and Implementation of Block Transporter Planning System)

  • 문종헌;유원선;차주환
    • 대한조선학회논문집
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    • 제53권2호
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    • pp.115-126
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    • 2016
  • In the process of ship building, it is known that the maintenance of working period and saving cost are one of the important part during the logistics of blocks transportation. Precise operational planning inside the shipyard plays a big role for a smooth transportation of blocks. But many problems arise in the process of block transportation such as the inevitable road damage during the transportation of the blocks, unpredictable stockyard utilization of the road associated with a particular lot number, addition of unplanned blocks. Therefore, operational plan needs to be re-established frequently in real time for an efficient block management. In order to find the shortest path between lot numbers, there are several representative methods such as Floyd algorithm that has the characteristics of many-to-many mapping, Dijkstra algorithm that has the characteristic of one-to-many mapping, and the A* algorithm which has the one-to-one mapping, but many authors have published without the mutual comparisons of these algorithms. In this study, some appropriate comparison have been reviewed about the advantages and disadvantages of these algorithms in terms of precision and cost analysis of calculating the paths and planning system to operate the transporters. The flexible operating plan is proposed to handle a situation such as damaged path, changing process during block transportation. In addition, an operational algorithm of a vacant transporter is proposed to cover the shortest path in a minimum time considering the situation of transporter rotation for practical use.

교통망 분석에서 K경로탐색 알고리즘에 관한 연구(Ordered Heap Tree 구축방식을 중심으로) (A Study on the K Shortest Paths Algorithm in a Transportation Network (Using Ordered Heap Tree))

  • 임강원;양승묵;신성일
    • 대한교통학회지
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    • 제23권8호
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    • pp.113-128
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    • 2005
  • 일반적으로 현실(특히 도시) 교통망에서 교차로를 반복해서 방문하는 통행은 존재하지만, 가로를 반복해서 주행하는 현상은 존재하지 않는다. 교통망에서의 루프형 통행은 링크의 반복이 허용되지 않는 링크 비루프(Link Loopless Path) 통행으로 축소된다. 본 연구에서는 K개의 경로탐색에서 기존의 방식과 달리 Heap Ordered Tree를 이용하여 월등한 수행속도(최악의 경우) O(m+ n log n+ K log K)로서 수행되는 Eppstein 알고리즘과 Jimenez et al의 LVEA을 고찰하여, 이들 알고리즘의 문제점인 링크루프의 발생을 제어하는 방안을 제어하도록 한다. 사례연구를 통하여 제안된 알고리즘을 검증 평가한다.

Object-Transportation Control of Cooperative AGV Systems Based on Virtual-Passivity Decentralized Control Algorithm

  • Suh, Jin-Ho;Lee, Young-Jin;Lee, Kwon-Soon
    • Journal of Mechanical Science and Technology
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    • 제19권9호
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    • pp.1720-1730
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    • 2005
  • Automatic guided vehicle in the factory has an important role to advance the flexible manufacturing system. In this paper, we propose a novel object-transportation control algorithm of cooperative AGV systems to apply decentralized control to multiple AGV systems. Each AGV system is under nonholonomic constraints and conveys a common object-transportation in a horizontal plain. Moreover it is shown that cooperative robot systems ensure stability and the velocities of augmented systems convergence to a scaled multiple of each desired velocity field for cooperative AGV systems. Finally, the application of proposed virtual passivity-based decentralized control algorithm via system augmentation is applied to trace a circle. Finally, the simulation and experimental results for the object-transportation by two AGV systems illustrates the validity of the proposed virtual-passivity decentralized control algorithm.