In a general case, container ship serves many different ports on each voyage. A stowage planning for container ship made at one port must take account of the influence on subsequent ports. So the complexity of stowage...In a general case, container ship serves many different ports on each voyage. A stowage planning for container ship made at one port must take account of the influence on subsequent ports. So the complexity of stowage planning problem increases due to its multi-ports nature. This problem is NP-hard problem. In order to reduce the computational complexity, the problem is decomposed into two sub-problems in this paper. First, container ship stowage problem (CSSP) is regarded as 'packing problem', ship-bays on the board of vessel are regarded as bins, the number of slots at each bay are taken as capacities of bins, and containers with different characteristics (homogeneous containers group) are treated as items packed. At this stage, there are two objective functions, one is to minimize the number of bays packed by containers and the other is to minimize the number of overstows. Secondly, containers assigned to each bays at first stage are allocate to special slot, the objective functions are to minimize the metacentric height, heel and overstows.The taboo search heuristics algorithm are used to solve the subproblem. The main focus of this paper is on the first subproblem. A case certifies the feasibility of the model and algorithm.展开更多
Containership stowage plans are a pivotal teaches in the system of container transportation.With the increasing containers shipping,planning containership stowage has become more and more complicated.So intelligent st...Containership stowage plans are a pivotal teaches in the system of container transportation.With the increasing containers shipping,planning containership stowage has become more and more complicated.So intelligent stowage planning for containerships is of great significance.An effective stowage plan may improve efficiency of transportation system.First,the progress of containership stowage plan at home and abroad is reviewed,including the latest developments,such as the application of various optimization methods and computer techniques to the problem.Then,the complexities of the problem are discussed and areas where investigations are still needed are pointed out.This will provide a reference for further research on the subject.展开更多
The operating efficiency of container shipping lines depends on proper resource allocation of container shipping.A deterministic model was developed for shipping lines based on the equilibrium principle.The objective ...The operating efficiency of container shipping lines depends on proper resource allocation of container shipping.A deterministic model was developed for shipping lines based on the equilibrium principle.The objective was to optimize the resource allocation for container lines considering ship size,container deployment,and slot allocation.The deterministic model was then expanded to a robust optimization model accounting for the uncertain factors,while ship size was treated as the design variable and slot allocation as the control variable.The effectiveness of the proposed model is demonstrated using a pendulum shipping line as an example.The results indicate that infeasible solutions will increase and the model robustness will be enhanced by an increased penalty coefficient and the solution robustness will be enhanced by increasing the preference coefficient.The optimization model simultaneously considers demand uncertainty,model robustness,and risk preference of the decision maker to agree better with actual practices.展开更多
为解决集装箱船舶贝内配载优化问题,以最小化倒箱次数为目标建立数学模型。提出基于力矩平衡和逐列装载的装船规则(ship loading rule based on moment balance and stowing column by column,SLR-MBSCC),根据装船方向的不同,将SLR-MBSC...为解决集装箱船舶贝内配载优化问题,以最小化倒箱次数为目标建立数学模型。提出基于力矩平衡和逐列装载的装船规则(ship loading rule based on moment balance and stowing column by column,SLR-MBSCC),根据装船方向的不同,将SLR-MBSCC规则分为由内向外(Inside-Out)装船和由外向内(Out-Inside)装船的两种规则。采用演化策略算法(ES),设计二维实数编码和基于SLR-MBSCC规则的解码方法,采用基于三点交叉互换的重组算子和基于两点互换的变异算子。在两种不同方向装船规则中,算例计算表明,由内向外方向下的规则对于减小横倾力矩更有效。通过不同规模算例分析验证了演化策略算法求解贝内配载问题的有效性。展开更多
基金Supported by a Special Fund Support Item of Doctor Subject of Colleges and Universities (No. 2000014125)
文摘In a general case, container ship serves many different ports on each voyage. A stowage planning for container ship made at one port must take account of the influence on subsequent ports. So the complexity of stowage planning problem increases due to its multi-ports nature. This problem is NP-hard problem. In order to reduce the computational complexity, the problem is decomposed into two sub-problems in this paper. First, container ship stowage problem (CSSP) is regarded as 'packing problem', ship-bays on the board of vessel are regarded as bins, the number of slots at each bay are taken as capacities of bins, and containers with different characteristics (homogeneous containers group) are treated as items packed. At this stage, there are two objective functions, one is to minimize the number of bays packed by containers and the other is to minimize the number of overstows. Secondly, containers assigned to each bays at first stage are allocate to special slot, the objective functions are to minimize the metacentric height, heel and overstows.The taboo search heuristics algorithm are used to solve the subproblem. The main focus of this paper is on the first subproblem. A case certifies the feasibility of the model and algorithm.
基金Supported by High-tech Research of Educational Department of Liaoning Province (No.05L091)a Special Fund Support Item of Doctor Subject of Colleges and Universities(No.2000014125)
文摘Containership stowage plans are a pivotal teaches in the system of container transportation.With the increasing containers shipping,planning containership stowage has become more and more complicated.So intelligent stowage planning for containerships is of great significance.An effective stowage plan may improve efficiency of transportation system.First,the progress of containership stowage plan at home and abroad is reviewed,including the latest developments,such as the application of various optimization methods and computer techniques to the problem.Then,the complexities of the problem are discussed and areas where investigations are still needed are pointed out.This will provide a reference for further research on the subject.
基金Supported by the Specialized Research Fund for the Doctoral Program of Higher Education of MOE,PRC (No 20092125120001)
文摘The operating efficiency of container shipping lines depends on proper resource allocation of container shipping.A deterministic model was developed for shipping lines based on the equilibrium principle.The objective was to optimize the resource allocation for container lines considering ship size,container deployment,and slot allocation.The deterministic model was then expanded to a robust optimization model accounting for the uncertain factors,while ship size was treated as the design variable and slot allocation as the control variable.The effectiveness of the proposed model is demonstrated using a pendulum shipping line as an example.The results indicate that infeasible solutions will increase and the model robustness will be enhanced by an increased penalty coefficient and the solution robustness will be enhanced by increasing the preference coefficient.The optimization model simultaneously considers demand uncertainty,model robustness,and risk preference of the decision maker to agree better with actual practices.
文摘在分析影响集装箱的装载效率时,考虑场内拖车在码头堆场和岸边装卸桥之间的移动距离,将配载问题看成是以码头堆场B ay位上的集装箱为供给、船舶B ay上的空箱位为需求的运输问题,以场内拖车将码头堆场集装箱送到岸边装卸桥所运行的距离最短为目标,建立配载模型并应用Hop fie ld神经网络模型进行计算机模拟.模拟结果说明,所提出的优化模型可以减少场内拖车运行的距离,提高集装箱装载效率,为合理进行集装箱船配载提供了一个参考模型.
文摘为解决集装箱船舶贝内配载优化问题,以最小化倒箱次数为目标建立数学模型。提出基于力矩平衡和逐列装载的装船规则(ship loading rule based on moment balance and stowing column by column,SLR-MBSCC),根据装船方向的不同,将SLR-MBSCC规则分为由内向外(Inside-Out)装船和由外向内(Out-Inside)装船的两种规则。采用演化策略算法(ES),设计二维实数编码和基于SLR-MBSCC规则的解码方法,采用基于三点交叉互换的重组算子和基于两点互换的变异算子。在两种不同方向装船规则中,算例计算表明,由内向外方向下的规则对于减小横倾力矩更有效。通过不同规模算例分析验证了演化策略算法求解贝内配载问题的有效性。
