To improve the disassembly efficiency of a U-shaped disassembly line and reduce the potentially harmful effects on the environment and human health,we study the multi-product U-shaped disassembly line balancing proble...To improve the disassembly efficiency of a U-shaped disassembly line and reduce the potentially harmful effects on the environment and human health,we study the multi-product U-shaped disassembly line balancing problem with a fixed number of stations(MUDLBPF).Firstly,we formulate a mathematical model aimed at minimizing cycle time,balancing loads,and reducing hazard indicators.Secondly,a multi-objective variable neighborhood search(MOVNS)algorithm is proposed.A multi-segment encoding method is proposed to maintain the independence of different products.Considering the characteristics of multiple products,a two-stage decoding method is presented.The method includes product assignment and task assignment.To optimize decoding efficiency,a minimum deviation method is put forward to generate feasible solutions.A segmented neighborhood structure containing seven operators is developed to improve the search efficiency.Finally,numerical experiments are performed and the results show that the MOVNS can solve the MUDLBPF effectively and efficiently.展开更多
Considering the development of urban freight transport,this paper presents an operational strategy for freight transport based on the urban metro system.To improve the alignment between service capacity and transport ...Considering the development of urban freight transport,this paper presents an operational strategy for freight transport based on the urban metro system.To improve the alignment between service capacity and transport demand under passenger and freight co-transportation(PFCT),a mixed-integer nonlinear programming model(MINLP)is developed to simultaneously optimize the train timetable(TT)and rolling stock circulation plan(RSCP),with particular consideration of flexible train composition mode and skip-stop strategies.Moreover,by introducing allocation rules for passengers and freight,the tripartite interests of operators,passengers,and freight agents are synergistically considered in the proposed model.To facilitate the model solution,a variable neighborhood search(VNS)algorithm is designed for the generation of high-quality solutions in a reasonable computational time.Finally,based on a simplified example and empirical data from the Beijing Metro Yizhuang Line,several sets of numerical examples are implemented to validate the applicability and effectiveness of the model and the approach.展开更多
Aiming at the intervention decision-making problem in manned/unmanned aerial vehicle（MAV/UAV） cooperative engagement, this paper carries out a research on allocation strategy of emergency discretion based on human f...Aiming at the intervention decision-making problem in manned/unmanned aerial vehicle（MAV/UAV） cooperative engagement, this paper carries out a research on allocation strategy of emergency discretion based on human factors engineering（HFE）.Firstly, based on the brief review of research status of HFE, it gives structural description to emergency in the process of cooperative engagement and analyzes intervention of commanders. After that,constraint conditions of intervention decision-making of commanders based on HFE（IDMCBHFE） are given, and the mathematical model, which takes the overall efficiency value of handling emergencies as the objective function, is established. Then, through combining K-best and variable neighborhood search（VNS） algorithm, a K-best optimization variable neighborhood search mixed algorithm（KBOVNSMA） is designed to solve the model. Finally,through three groups of simulation experiments, effectiveness and superiority of the proposed algorithm are verified.展开更多
基金supported by the National Natural Science Foundation of China(No.52175449).
文摘To improve the disassembly efficiency of a U-shaped disassembly line and reduce the potentially harmful effects on the environment and human health,we study the multi-product U-shaped disassembly line balancing problem with a fixed number of stations(MUDLBPF).Firstly,we formulate a mathematical model aimed at minimizing cycle time,balancing loads,and reducing hazard indicators.Secondly,a multi-objective variable neighborhood search(MOVNS)algorithm is proposed.A multi-segment encoding method is proposed to maintain the independence of different products.Considering the characteristics of multiple products,a two-stage decoding method is presented.The method includes product assignment and task assignment.To optimize decoding efficiency,a minimum deviation method is put forward to generate feasible solutions.A segmented neighborhood structure containing seven operators is developed to improve the search efficiency.Finally,numerical experiments are performed and the results show that the MOVNS can solve the MUDLBPF effectively and efficiently.
基金supported by the Beijing Natural Science Foundation(9252012)the National Natural Science Foundation of China(72371015,72288101,72431002,and 72161010)Key Laboratory of Railway Industry on Plateau Railway Transportation Intelligent Management and Control(GYYSHZ2301)。
文摘Considering the development of urban freight transport,this paper presents an operational strategy for freight transport based on the urban metro system.To improve the alignment between service capacity and transport demand under passenger and freight co-transportation(PFCT),a mixed-integer nonlinear programming model(MINLP)is developed to simultaneously optimize the train timetable(TT)and rolling stock circulation plan(RSCP),with particular consideration of flexible train composition mode and skip-stop strategies.Moreover,by introducing allocation rules for passengers and freight,the tripartite interests of operators,passengers,and freight agents are synergistically considered in the proposed model.To facilitate the model solution,a variable neighborhood search(VNS)algorithm is designed for the generation of high-quality solutions in a reasonable computational time.Finally,based on a simplified example and empirical data from the Beijing Metro Yizhuang Line,several sets of numerical examples are implemented to validate the applicability and effectiveness of the model and the approach.
基金supported by the National Natural Science Foundation of China(61573017)the Doctoral Foundation of Air Force Engineering University(KGD08101604)
文摘Aiming at the intervention decision-making problem in manned/unmanned aerial vehicle（MAV/UAV） cooperative engagement, this paper carries out a research on allocation strategy of emergency discretion based on human factors engineering（HFE）.Firstly, based on the brief review of research status of HFE, it gives structural description to emergency in the process of cooperative engagement and analyzes intervention of commanders. After that,constraint conditions of intervention decision-making of commanders based on HFE（IDMCBHFE） are given, and the mathematical model, which takes the overall efficiency value of handling emergencies as the objective function, is established. Then, through combining K-best and variable neighborhood search（VNS） algorithm, a K-best optimization variable neighborhood search mixed algorithm（KBOVNSMA） is designed to solve the model. Finally,through three groups of simulation experiments, effectiveness and superiority of the proposed algorithm are verified.
