针对汽车涂装生产的车辆路由调度问题,为降低涂装作业颜色切换次数及后续生产序列偏差,实现有限的资源内制造成本最低。基于涂装车间内具有多线性缓冲存储区的特点,以随机的待喷涂车辆集合为输入,建立以颜色切换次数最少及总装生产需求...针对汽车涂装生产的车辆路由调度问题,为降低涂装作业颜色切换次数及后续生产序列偏差,实现有限的资源内制造成本最低。基于涂装车间内具有多线性缓冲存储区的特点,以随机的待喷涂车辆集合为输入,建立以颜色切换次数最少及总装生产需求队列偏差最小为目标的MILP(mixed integer linear programming)模型,入库基于启发式规则,出库通过改进遗传算法求解,输出车辆路由调度方案。最后以某新能源汽车厂涂装车间为例,开发了一套路由调度系统,验证了所提出的多线性缓冲区联合调度方法,使得涂装切换成本下降80%左右,总装生产需求偏差成本下降10%左右。展开更多
This paper proposes an optimization model for the airport ground movement problem(GMP)based on bilevel programming to address taxi conflicts on the airport ground and to improve the operating safety and efficiency.To ...This paper proposes an optimization model for the airport ground movement problem(GMP)based on bilevel programming to address taxi conflicts on the airport ground and to improve the operating safety and efficiency.To solve GMP,an iterative heuristic algorithm is designed.Instead of separately investigating each problem,this model simultaneously coordinates and optimizes the aircraft routing and scheduling.A simulation test is conducted on Nanjing Lukou International Airport(NKG)and the results show that the bilevel programming model can clearly outperform the widely used first-come-first-service(FCFS)scheduling scheme in terms of aircraft operational time under the precondition of none conflict.The research effort demonstrates that with the reduced operating cost and the improved overall efficiency,the proposed model can assist operations of the airports that are facing increasing traffic demand and working at almost maximum capacity.展开更多
This letter presents an efficient scheduling algorithm DTRR (Dual-Threshold Round Robin) for input-queued switches. In DTRR, a new matched input and output by round robin in a cell time will be locked by two self-adap...This letter presents an efficient scheduling algorithm DTRR (Dual-Threshold Round Robin) for input-queued switches. In DTRR, a new matched input and output by round robin in a cell time will be locked by two self-adaptive thresholds whenever the queue length or the wait-time of the head cell in the corresponding Virtual Output Queue (VOQ) exceeds the thresholds. The locked input and output will be matched directly in the succeeding cell time until they are unlocked. By employing queue length and wait-time thresholds which are updated every cell time simultane- ously, DTRR achieves a good tradeoff between the performance and hardware complexity. Simula- tion results indicate that the delay performance of DTRR is competitive compared to other typical scheduling algorithms under various traffic patterns especially under diagonal traffic.展开更多
ISA100.11 a industrial wireless network standard is based on a deterministic scheduling mechanism.For the timeslot delay caused by deterministic scheduling,a routing algorithm is presented for industrial environments....ISA100.11 a industrial wireless network standard is based on a deterministic scheduling mechanism.For the timeslot delay caused by deterministic scheduling,a routing algorithm is presented for industrial environments.According to timeslot,superframe,links,channel and data retransmission of deterministic scheduling mechanisms that affect the design of the routing algorithm,the algorithm selects the link quality,timeslot delay and retransmission delay as the routing criteria and finds the optimum communication path by k shortest paths algorithm.Theoretical analysis and experimental verification show that the optimal paths selected by the algorithm not only have high link quality and low retransmission delay,but also meet the requirements of the deterministic scheduling.The algorithm can effectively solve the problem of packet loss and transmission delay during data transmission,and provide a valuable solution for efficient data transmission based on determinacy.展开更多
针对汽车装配过程特点与管控要点,构建了基于Prism/MVVM(model-viewview model)架构的汽车装配过程管控一体化系统.然后,对系统实现的关键技术进行研究,基于企业服务总线(enterprise service bus,ESB)技术以松散耦合方式实现异构管理系...针对汽车装配过程特点与管控要点,构建了基于Prism/MVVM(model-viewview model)架构的汽车装配过程管控一体化系统.然后,对系统实现的关键技术进行研究,基于企业服务总线(enterprise service bus,ESB)技术以松散耦合方式实现异构管理系统间集成,依据不同作业环境采取自动采集与移动式作业采集感知汽车装配过程,设计可配置图形模型的车辆自动识别(automatic vehicle identification,AVI)跟踪模式以满足不同类别和不同层级监管人员需求,基于采集器、触发器、调度器与控制器实现汽车装配过程中自动路由控制(route control,RC)调度.设计系统集成灵活、模块可插拔、界面与业务可分离设计开发、具有良好的扩展性与维护性.最后,企业案例验证了系统有效性.展开更多
文摘针对汽车涂装生产的车辆路由调度问题,为降低涂装作业颜色切换次数及后续生产序列偏差,实现有限的资源内制造成本最低。基于涂装车间内具有多线性缓冲存储区的特点,以随机的待喷涂车辆集合为输入,建立以颜色切换次数最少及总装生产需求队列偏差最小为目标的MILP(mixed integer linear programming)模型,入库基于启发式规则,出库通过改进遗传算法求解,输出车辆路由调度方案。最后以某新能源汽车厂涂装车间为例,开发了一套路由调度系统,验证了所提出的多线性缓冲区联合调度方法,使得涂装切换成本下降80%左右,总装生产需求偏差成本下降10%左右。
基金supported by the National Natural Science Foundations of China(Nos.U1933118,U2033205)。
文摘This paper proposes an optimization model for the airport ground movement problem(GMP)based on bilevel programming to address taxi conflicts on the airport ground and to improve the operating safety and efficiency.To solve GMP,an iterative heuristic algorithm is designed.Instead of separately investigating each problem,this model simultaneously coordinates and optimizes the aircraft routing and scheduling.A simulation test is conducted on Nanjing Lukou International Airport(NKG)and the results show that the bilevel programming model can clearly outperform the widely used first-come-first-service(FCFS)scheduling scheme in terms of aircraft operational time under the precondition of none conflict.The research effort demonstrates that with the reduced operating cost and the improved overall efficiency,the proposed model can assist operations of the airports that are facing increasing traffic demand and working at almost maximum capacity.
基金Supported by the National Natural Science Foundation of China (No.60472057).
文摘This letter presents an efficient scheduling algorithm DTRR (Dual-Threshold Round Robin) for input-queued switches. In DTRR, a new matched input and output by round robin in a cell time will be locked by two self-adaptive thresholds whenever the queue length or the wait-time of the head cell in the corresponding Virtual Output Queue (VOQ) exceeds the thresholds. The locked input and output will be matched directly in the succeeding cell time until they are unlocked. By employing queue length and wait-time thresholds which are updated every cell time simultane- ously, DTRR achieves a good tradeoff between the performance and hardware complexity. Simula- tion results indicate that the delay performance of DTRR is competitive compared to other typical scheduling algorithms under various traffic patterns especially under diagonal traffic.
基金Supported by the National Natural Science Foundation of China(No.61301125)the National High Technology Research and Development Programme of China(No.0AA0401028003)+2 种基金National Science and Technology Major Project(No.2013ZX03005005)the Fundamental and Advanced Research Program of Chongqing(No.cstc2013jcyjA40008)the Youth Top-notch Talent Support Program of Chongqing(No.2013-139)
文摘ISA100.11 a industrial wireless network standard is based on a deterministic scheduling mechanism.For the timeslot delay caused by deterministic scheduling,a routing algorithm is presented for industrial environments.According to timeslot,superframe,links,channel and data retransmission of deterministic scheduling mechanisms that affect the design of the routing algorithm,the algorithm selects the link quality,timeslot delay and retransmission delay as the routing criteria and finds the optimum communication path by k shortest paths algorithm.Theoretical analysis and experimental verification show that the optimal paths selected by the algorithm not only have high link quality and low retransmission delay,but also meet the requirements of the deterministic scheduling.The algorithm can effectively solve the problem of packet loss and transmission delay during data transmission,and provide a valuable solution for efficient data transmission based on determinacy.
