在全球零售额和当天交货量不断增长的时代,实现订单的快速交付和优质分批是影响移动机器人履行系统(Robotic Mobile Fulfillment Systems,RMFS)拣选效率的关键因素.为构造高质量订单分配批次、提升RMFS系统拣选效率,提出融合大邻域搜索...在全球零售额和当天交货量不断增长的时代,实现订单的快速交付和优质分批是影响移动机器人履行系统(Robotic Mobile Fulfillment Systems,RMFS)拣选效率的关键因素.为构造高质量订单分配批次、提升RMFS系统拣选效率,提出融合大邻域搜索的改进差分进化算法(LNS_DE),引入大邻域搜索的破坏与修复思想及一批基于随机、基于最大代价贡献和基于集中批次的移除算子以及新的插入算子组件,以最小化订单总延迟时间为目标建立订单分批优化模型,并针对不同订单规模算例进行实验仿真.仿真结果表明,所提出的订单分批优化算法较差分进化算法(DE)相比求解质量更优,性能更稳定、收敛速度更快,尤其当订单数量增大时,LNS_DE算法解的平均值优化比例不断扩大,这为提高RMFS系统拣选效率,实现订单快速响应提供有效决策指导.展开更多
随着电子商务的蓬勃发展,海量客户需求和高频率、多品种、小批量的订单特性为订单拣选业务带来巨大挑战。在物流智能化的趋势下,大量电商企业采用移动机器人拣货系统(Robotic Mobile Fulfillment System,RMFS)进行订单拣选。订单分配和...随着电子商务的蓬勃发展,海量客户需求和高频率、多品种、小批量的订单特性为订单拣选业务带来巨大挑战。在物流智能化的趋势下,大量电商企业采用移动机器人拣货系统(Robotic Mobile Fulfillment System,RMFS)进行订单拣选。订单分配和拣选路径规划是影响仓库订单拣选效率的关键决策。为了提高电商RMFS系统拣选效率,降低仓库运营成本,基于电商企业多订单、多货架、多拣选站下的拣选业务场景,以最小化机器人负载距离为目标,构建订单分配与路径规划联合优化模型,设计两阶段的A*算法和自适应大领域搜索算法(Adaptive Large Neighborhood Search,ALNS),在ALNS算法原有框架的基础上提出新的移除和修复算子以适应订单分配问题,并针对30个不同规模算例进行计算分析。计算结果表明,所提出的优化方法收敛快、性能稳定,能够有效缩短机器人行走距离,相比先到先拣选策略最大可缩短47.6%的机器人负载距离。同时,也可在更短时间内获得与CPLEX求解质量相近的解。尤其是当订单数量增长时,相比CPLEX具有突出时间优势,可以实现电商仓储资源的合理调度和配置,从而为电商企业仓储智能化提供有效决策指导。展开更多
During the last two decades,many algorithms were developed to simulate the solidification process for different casting methods like ingots,continuous casting of steel and the direct chill cast of aluminum.Experiments...During the last two decades,many algorithms were developed to simulate the solidification process for different casting methods like ingots,continuous casting of steel and the direct chill cast of aluminum.Experiments performed under exactly known conditions and with the detailed knowledge of meso-and micro-structures are required for validating these simulations.The aim of this paper is to give a data set to validate these simulations.Unidirectional solidification experiments were performed by using a rotating magnetic field(RMF)to study the effect of melt flow on the solidified micro-and meso-structure of the Al-7wt.%Si binary alloy.The first and the third 1/3 parts of samples were solidified without magnetic stirring,and the second(middle)1/3 part was solidified by using magnetic stirring.The magnetic induction was 10 m T,the temperature gradient was~7 K/mm,and the sample movement velocity was 0.1 mm/s.On the longitudinal section of the sample,the columnar/equiaxed transition(CET),the equiaxed/columnar transition(ECT),the secondary dendrite arm spacing(SDAS),and the macrosegregation(concentration distribution and the amount of eutectic)were investigated.The primary dendrite arm spacing(PDAS)and the grain structure were studied on the cross-section after color etching.展开更多
将大肠杆菌的rpoS和rmf基因突变型和野生型菌株分别培养在营养丰富的LB培养基和成分有限的EP培养基上。在相同条件下,进入稳定期后的突变型菌株的活细胞数低于野生菌株。采用 Western blot方法测定了不同基因产物在稳定期的变化。σ^(38...将大肠杆菌的rpoS和rmf基因突变型和野生型菌株分别培养在营养丰富的LB培养基和成分有限的EP培养基上。在相同条件下,进入稳定期后的突变型菌株的活细胞数低于野生菌株。采用 Western blot方法测定了不同基因产物在稳定期的变化。σ^(38)对RNA聚合酶核心酶亚单位结构基因 rpoA、rpoB、rpoC以及groEs和tufA基因的表达影响不大,能抑制crp和促进rmf的表达。RMF在营养丰富的条件下对rpoA、rpoD,groEl、rho、tufA和ompA基因的表达有促进作用,而在EP条件下的影响并不明显,对crp和rpoS的表达分别有抑制和促进作用。展开更多
The relativistic mean-field （RMF） theory is used to calculate the properties of A =7-9 drip-line nuclei ^7Li, ^7;9Be, ^8;9B, and ^9C. Systematic deviations between experimental and theoretical binding energies are f...The relativistic mean-field （RMF） theory is used to calculate the properties of A =7-9 drip-line nuclei ^7Li, ^7;9Be, ^8;9B, and ^9C. Systematic deviations between experimental and theoretical binding energies are found. Possible reasons of these systematic deviations are discussed in terms of pairing energy. The root-mean-square （rms） radii of matter distributions for these nuclei agree with the experimental data quite well. The one-proton halo structure in ^8B is reproduced well, and the two-proton halo in ^9C is predicted. The calculations show that the RMF theory is valid in studying the properties of light drip-line nuclei.展开更多
订单拣选效率是移动机器人拣货系统(robotic mobile fulfillment systems,RMFS)优化研究的重点关注指标。为减少RMFS中自动导引运输车充电过程的排队等待时间,提出一种灵活充电策略,并针对RMFS的任务分配与充电调度协同优化问题建立以...订单拣选效率是移动机器人拣货系统(robotic mobile fulfillment systems,RMFS)优化研究的重点关注指标。为减少RMFS中自动导引运输车充电过程的排队等待时间,提出一种灵活充电策略,并针对RMFS的任务分配与充电调度协同优化问题建立以最小化订单拣选时间为目标的混合整数线性规划模型。为提高求解效率,设计了一种嵌入强化学习的遗传算法。实验结果验证了所提算法的有效性和协同优化的重要性,同时表明采用所提充电策略能够减少充电等待时间,进而提高订单拣选效率。展开更多
从相对论平均场(Relativistic Mean Field,RMF)理论出发,考虑核子、超子和介子的相互作用,研究了一定温度(T=20 MeV)下,各种不同相互作用参数组(DDME1、TW99、NL2、TM1、TM2、GL85和GL97)对中子星物质的粒子组成、状态方程和质量等的影...从相对论平均场(Relativistic Mean Field,RMF)理论出发,考虑核子、超子和介子的相互作用,研究了一定温度(T=20 MeV)下,各种不同相互作用参数组(DDME1、TW99、NL2、TM1、TM2、GL85和GL97)对中子星物质的粒子组成、状态方程和质量等的影响.发现在不同参数组下,相对论平均场对中子星性质和整体结构的描述有所不同.其中DDME1和TW99计算的结果基本相同,它们给出较强的介子场势、较小的超子转变密度、较硬的物态方程和较大的质量极限;而GL97、TM1和GL85给出较弱的介子场势、较软的物态方程以及比较小的极限质量.而NL2、TM2参数组所给出的结果则介于它们之间.展开更多
文摘在全球零售额和当天交货量不断增长的时代,实现订单的快速交付和优质分批是影响移动机器人履行系统(Robotic Mobile Fulfillment Systems,RMFS)拣选效率的关键因素.为构造高质量订单分配批次、提升RMFS系统拣选效率,提出融合大邻域搜索的改进差分进化算法(LNS_DE),引入大邻域搜索的破坏与修复思想及一批基于随机、基于最大代价贡献和基于集中批次的移除算子以及新的插入算子组件,以最小化订单总延迟时间为目标建立订单分批优化模型,并针对不同订单规模算例进行实验仿真.仿真结果表明,所提出的订单分批优化算法较差分进化算法(DE)相比求解质量更优,性能更稳定、收敛速度更快,尤其当订单数量增大时,LNS_DE算法解的平均值优化比例不断扩大,这为提高RMFS系统拣选效率,实现订单快速响应提供有效决策指导.
文摘随着电子商务的蓬勃发展,海量客户需求和高频率、多品种、小批量的订单特性为订单拣选业务带来巨大挑战。在物流智能化的趋势下,大量电商企业采用移动机器人拣货系统(Robotic Mobile Fulfillment System,RMFS)进行订单拣选。订单分配和拣选路径规划是影响仓库订单拣选效率的关键决策。为了提高电商RMFS系统拣选效率,降低仓库运营成本,基于电商企业多订单、多货架、多拣选站下的拣选业务场景,以最小化机器人负载距离为目标,构建订单分配与路径规划联合优化模型,设计两阶段的A*算法和自适应大领域搜索算法(Adaptive Large Neighborhood Search,ALNS),在ALNS算法原有框架的基础上提出新的移除和修复算子以适应订单分配问题,并针对30个不同规模算例进行计算分析。计算结果表明,所提出的优化方法收敛快、性能稳定,能够有效缩短机器人行走距离,相比先到先拣选策略最大可缩短47.6%的机器人负载距离。同时,也可在更短时间内获得与CPLEX求解质量相近的解。尤其是当订单数量增长时,相比CPLEX具有突出时间优势,可以实现电商仓储资源的合理调度和配置,从而为电商企业仓储智能化提供有效决策指导。
基金financially supported by the project entitled“Formation of as-solidified structure and macrosegregation during unidirectional solidification under controlled flow conditions”of the National Research Development,and Investigation Office(No.130946)。
文摘During the last two decades,many algorithms were developed to simulate the solidification process for different casting methods like ingots,continuous casting of steel and the direct chill cast of aluminum.Experiments performed under exactly known conditions and with the detailed knowledge of meso-and micro-structures are required for validating these simulations.The aim of this paper is to give a data set to validate these simulations.Unidirectional solidification experiments were performed by using a rotating magnetic field(RMF)to study the effect of melt flow on the solidified micro-and meso-structure of the Al-7wt.%Si binary alloy.The first and the third 1/3 parts of samples were solidified without magnetic stirring,and the second(middle)1/3 part was solidified by using magnetic stirring.The magnetic induction was 10 m T,the temperature gradient was~7 K/mm,and the sample movement velocity was 0.1 mm/s.On the longitudinal section of the sample,the columnar/equiaxed transition(CET),the equiaxed/columnar transition(ECT),the secondary dendrite arm spacing(SDAS),and the macrosegregation(concentration distribution and the amount of eutectic)were investigated.The primary dendrite arm spacing(PDAS)and the grain structure were studied on the cross-section after color etching.
文摘将大肠杆菌的rpoS和rmf基因突变型和野生型菌株分别培养在营养丰富的LB培养基和成分有限的EP培养基上。在相同条件下,进入稳定期后的突变型菌株的活细胞数低于野生菌株。采用 Western blot方法测定了不同基因产物在稳定期的变化。σ^(38)对RNA聚合酶核心酶亚单位结构基因 rpoA、rpoB、rpoC以及groEs和tufA基因的表达影响不大,能抑制crp和促进rmf的表达。RMF在营养丰富的条件下对rpoA、rpoD,groEl、rho、tufA和ompA基因的表达有促进作用,而在EP条件下的影响并不明显,对crp和rpoS的表达分别有抑制和促进作用。
基金supported by the Knowledge Innovation Project of Chinese Academy of Sciences under Grant No.KJCX3-SYW-N2
文摘The relativistic mean-field （RMF） theory is used to calculate the properties of A =7-9 drip-line nuclei ^7Li, ^7;9Be, ^8;9B, and ^9C. Systematic deviations between experimental and theoretical binding energies are found. Possible reasons of these systematic deviations are discussed in terms of pairing energy. The root-mean-square （rms） radii of matter distributions for these nuclei agree with the experimental data quite well. The one-proton halo structure in ^8B is reproduced well, and the two-proton halo in ^9C is predicted. The calculations show that the RMF theory is valid in studying the properties of light drip-line nuclei.
文摘订单拣选效率是移动机器人拣货系统(robotic mobile fulfillment systems,RMFS)优化研究的重点关注指标。为减少RMFS中自动导引运输车充电过程的排队等待时间,提出一种灵活充电策略,并针对RMFS的任务分配与充电调度协同优化问题建立以最小化订单拣选时间为目标的混合整数线性规划模型。为提高求解效率,设计了一种嵌入强化学习的遗传算法。实验结果验证了所提算法的有效性和协同优化的重要性,同时表明采用所提充电策略能够减少充电等待时间,进而提高订单拣选效率。
文摘从相对论平均场(Relativistic Mean Field,RMF)理论出发,考虑核子、超子和介子的相互作用,研究了一定温度(T=20 MeV)下,各种不同相互作用参数组(DDME1、TW99、NL2、TM1、TM2、GL85和GL97)对中子星物质的粒子组成、状态方程和质量等的影响.发现在不同参数组下,相对论平均场对中子星性质和整体结构的描述有所不同.其中DDME1和TW99计算的结果基本相同,它们给出较强的介子场势、较小的超子转变密度、较硬的物态方程和较大的质量极限;而GL97、TM1和GL85给出较弱的介子场势、较软的物态方程以及比较小的极限质量.而NL2、TM2参数组所给出的结果则介于它们之间.
