The uninterrupted operation of the quay crane(QC)ensures that the large container ship can depart port within laytime,which effectively reduces the handling cost for the container terminal and ship owners.The QC waiti...The uninterrupted operation of the quay crane(QC)ensures that the large container ship can depart port within laytime,which effectively reduces the handling cost for the container terminal and ship owners.The QC waiting caused by automated guided vehicles(AGVs)delay in the uncertain environment can be alleviated by dynamic scheduling optimization.A dynamic scheduling process is introduced in this paper to solve the AGV scheduling and path planning problems,in which the scheduling scheme determines the starting and ending nodes of paths,and the choice of paths between nodes affects the scheduling of subsequent AGVs.This work proposes a two-stage mixed integer optimization model to minimize the transportation cost of AGVs under the constraint of laytime.A dynamic optimization algorithm,including the improved rule-based heuristic algorithm and the integration of the Dijkstra algorithm and the Q-Learning algorithm,is designed to solve the optimal AGV scheduling and path schemes.A new conflict avoidance strategy based on graph theory is also proposed to reduce the probability of path conflicts between AGVs.Numerical experiments are conducted to demonstrate the effectiveness of the proposed model and algorithm over existing methods.展开更多
The essential drive of building a new countryside lies in scientific and technological innovation. Through expounding the scientific and technological demonstration benefits and roles of new countryside building in po...The essential drive of building a new countryside lies in scientific and technological innovation. Through expounding the scientific and technological demonstration benefits and roles of new countryside building in poverty-stricken mountainous area,the major problems and hardships of new countryside building in poverty-stricken area are analyzed and the new breakthroughs which should be focused on during the building of a new countryside are put forward. These breakthroughs include transforming the philosophy and approach of rural work; highlighting the construction of rural operation mode and rural socialized service system,and improving the quality of rural labors.展开更多
基金supported in part by the National Natural Science Foundation of China(61473053)the Science and Technology Innovation Foundation of Dalian,China(2020JJ26GX033)。
文摘The uninterrupted operation of the quay crane(QC)ensures that the large container ship can depart port within laytime,which effectively reduces the handling cost for the container terminal and ship owners.The QC waiting caused by automated guided vehicles(AGVs)delay in the uncertain environment can be alleviated by dynamic scheduling optimization.A dynamic scheduling process is introduced in this paper to solve the AGV scheduling and path planning problems,in which the scheduling scheme determines the starting and ending nodes of paths,and the choice of paths between nodes affects the scheduling of subsequent AGVs.This work proposes a two-stage mixed integer optimization model to minimize the transportation cost of AGVs under the constraint of laytime.A dynamic optimization algorithm,including the improved rule-based heuristic algorithm and the integration of the Dijkstra algorithm and the Q-Learning algorithm,is designed to solve the optimal AGV scheduling and path schemes.A new conflict avoidance strategy based on graph theory is also proposed to reduce the probability of path conflicts between AGVs.Numerical experiments are conducted to demonstrate the effectiveness of the proposed model and algorithm over existing methods.
基金Supported by Star Program of the State Ministry of Science&Technology "integration and application of the cycle mode of grain (vegetable)-swine-meth-ane-fertilizer"(2007EA820001)The Major Science and Technology Program of Guizhou Province "The Science and Technology Demonstration of a New Socialist Countryside Building of Hongyan Village"[QKHZDZXZ(2008)6003]
文摘The essential drive of building a new countryside lies in scientific and technological innovation. Through expounding the scientific and technological demonstration benefits and roles of new countryside building in poverty-stricken mountainous area,the major problems and hardships of new countryside building in poverty-stricken area are analyzed and the new breakthroughs which should be focused on during the building of a new countryside are put forward. These breakthroughs include transforming the philosophy and approach of rural work; highlighting the construction of rural operation mode and rural socialized service system,and improving the quality of rural labors.
