配送中心拣货作业中的订单分批策略研究

针对配送中心采取批量拣货时首先必须解决的订单问题，介绍了订单分批的四种方式及分批策略。同时针对固定时窗分批的不足，提出了时窗大小的动态设计方法。     

配送中心拣货系统中的分区策略研究

对影响配送中心拣货作业效率的分区策略进行了介绍，并对拣货分区设计的某些策略进行了举例说明。     

Benchmarking Warehousing and Distribution Operations: An Input-Output Approach

We developan input-output model of a warehouse system to assess operationalefficiency. Our model simultaneously accounts for all of thecritical resources (labor, space, storage and handling equipment)and the different workload requirements (broken case, full caseand pallet picking, storage and order accumulation) of a warehouse.We collected extensive data on 57 warehouse and distributionfacilities from a variety of industries, including auto parts,dental and office supplies, electronics, fine papers, hardware,health care, industrial packaging, mail order apparel, officemachines, photographic supplies, and wholesale drugs, and usedthe model to assess and compare their efficiencies. We offer3 conclusions based on a statistical analysis of the operatingefficiencies obtained from several models: Smaller warehouses tend to be more efficient than larger warehouses.Warehouses using lower levels of automation tend to be moreefficient. This association is more pronounced in small firms.Unionization is not negatively associated with efficiencyand in fact may actually contribute to higher efficiency.     

基于货物信息可追溯的RFID拣选作业系统

将射频识别技术应用于企业仓库中,采用播种式的拣选策略,设计了一种基于RFID技术的拣选作业系统,提高了拣选效率,简化了出库流程。同时,通过信息的记录与传输,提高了货物在出库与运输过程中的可追溯性,促进了物流与信息流的同步。     

基于订单网格化聚类方法的医药自动拣选系统与电子标签拣选系统的比较研究

通过对两种医药订单拣选系统（基于订单网格化聚类方法的医药自动拣选系统和电子标签拣选系统）的对比分析．提出了适合医药配送中心采用的高效率分拣的方法。系统订单拣选系统最常用的两种作业策略分区策略和分批策略本质上都是对订单的聚类,因此订单可以被分为很多一维单元化网格;根据各系统的逻辑运动关系,可得到单元化网格的拣选时间表达式;利用作业时间模型和空间填充线,对单元化网格进行聚类．得到二维系统的总订单拣选时间.最后通过实验研究．初步得出二者在拣选效率及补货效率等关键指标上的区别。     

卷烟配送中心自动分拣系统的规划设计

分拣系统是配送中心的核心环节,论文介绍了配送中心分拣系统规划的基本理论,其中包括拣选基本单位、作业方法、拣选信息和拣选设备等内容;概述了基于配送中心系统规划的订单资料EIQ分析思想,在订单资料分析的基础上对某卷烟配送中心分拣作业系统进行了规划设计,设计出一套复合式卷烟自动分拣系统,它弥补了现有卷烟分拣作业模式的缺陷,提高了卷烟分拣作业的效率,降低了工人的劳动强度。作为一种先进的分拣系统,它实现了准确、快捷、合理的条烟分拣。     

Testing random assignment to peer groups

Identification of peer effects is complicated by the fact that the individuals under study may select their peers. Random assignment to peer groups has proven useful to sidestep such a concern. In the absence of a formal randomization mechanism, it needs to be argued that assignment is “as good as” random. This paper introduces a simple yet powerful test to do so. We provide theoretical results for this test. As a by-product, we equally obtain such results for an approach popularized by Guryan et al. (2009). These results help to explain why this approach suffers from low power, as has been observed elsewhere.     

单品拣货研究

简述了单品拣货作业的基本方法，以设定的拣货系统为例．介绍了8种低成本的单品拣货模式，为配送中心拣货系统的设计和选择合适的单品拣货模式提供依据。     

立体车库随机车位分配与就近车位分配仿真及分析

在介绍巷道堆垛式自动化立体车库工作的基础上,建立了约束条件下的车辆入库、出库、因车位存满而离去的就近存取和随机存取策略车库工作模型。以车辆到达时间间隔服从泊松分布,库内存放时间服从正态分布的情况建立数学模型,采用Matlab编制仿真程序,对特定参数的模型进行了仿真,并给出分析结果。结果表明在文中参数设定情况下该车库车位利用率较高,采用就近存取策略比采用随机存取策略堆垛机运行距离短,能耗低,全年能耗降低显著。     

烟草商业配送物流设计分析

根据目前烟草配送的现状和发展趋势，着重介绍和分析了烟草商业配送物流设计中件烟存贮和条烟分拣的基本方式，并对相关主要设备和系统案例进行描述。     

仓库规划与设计的布局问题研究

从成本角度出发,在满足存储和分拣要求前提下,分别建立存储区和分拣区成本模型,确定存储区和分拣区的大小,使仓库经营活动成本最小。     

一种INSS动态反馈负载均衡算法

负载均衡策略是智能网络存储系统(INSS)的关键性技术之一。本文介绍了智能网络存储系统的存储结构,提出了一种新的负载均衡算法。该算法采用周期动态反馈原理,以节点的最小化负载方差为目标,动态调整节点分配权值,最后引入随机概率的转发模式。在实验室搭建的系统平台上,对该算法以及WRR和WLC两种负载均衡算法进行了对比测试,试验结果表明该算法性能更优。     

基于EIQ分析法的拣选策略运用

拣选作业的效率直接影响配送中心对客户订单履行的效率。运用EIQ分析法对订单出货材料进行分析,找出客户的订单特点,确定有效的拣选策略。运用有效的拣选策略可以提高订单的拣选效率和顾客的满意度。     

Optimizing the spatial assignment of schools to reduce both inequality of educational opportunity and potential opposition rate through introducing random mechanism into proximity-based system

A serious spatial inequality of educational opportunity was revealed worldwide, for wealthy families can access good schools by buying real estate with good school' enrollment quota. Although the existing studies had revealed that random-based school assignment can significantly improve equality of opportunity allocation, random mechanism was adopted only in few places. Two major resistances of introducing random mechanism exist: the possibility of increased commuting distance to schools and the effected relative beneficiaries. In order to make the random-based allocation more feasible, this study proposes a spatial optimization model to take these two factors into account into proximity-based school assignment system. The proposed multi-objective allocation model, with the constraint conditions of assigning students to 3 closest schools and school capacities, was developed in this study to minimize the spatial disparity of educational opportunity and the potential opposition rate of introducing random mechanism into proximity-based assignment system. The model will be solved by a heuristic algorithm and applied to a case study area of Shijingshan District, Beijing. The results showed that the proposed model could improve spatial equality of educational opportunity significantly, but along with a minor increase on commuting distance to schools. In addition, potential opponents of introducing random mechanism decrease as the weight of parameters related to opposition rate increases in the model, reducing nearly 10% in the best case. Therefore, the solutions provided by proposed model may encounter less resistance in a democratic voting system. However, the results also indicated that there would be some relative beneficiaries who may oppose introducing random mechanism into proximity-based school system even in the best case. This implies that, to achieve equal educational opportunity in the context of proximity-based school system, optimized allocation is needed along with a more even distribution of educational resources.     

Conditional distributions of generalized order statistics and some characterizations

Generalized order statistics have been introduced in Kamps (1995a). They enable a unified approach to several models of ordered random variables, e.g. (ordinary) order statistics, record values, sequential order statistics, record values from non-identical distributions. The purpose of this paper is to develop conditional distributions of one generalized order statistic given another and to characterize the underlying continuous distribution by different conditional expectations. Well-known results for ordinary order statistics and record values are extended to generalized order statistics. Received: July 1997     

准格尔宇星超市物流配送中心业务流程优化研究

配送中心是现代社会物流系统中的重要节点。通过对商品的进货、验收入库、仓储、订单处理、拣货、包装、分类、出货、检查、配送、信息处理等进行科学管理,可以大幅度减轻作业劳动强度,减少商品损耗,降低库存周转率,加速商品流通,同时提高社会满意程度,从而增强企业竞争力。文中首先分析了准格尔宇星超市配送中心的现状,找出其作业流程中的问题,提出了作业流程优化的对策,达到缩短流程作业时间、提高物流效率、提高服务水平、降低物流成本、提高企业竞争力的目的。     

Bayesian analysis of random coefficient logit models using aggregate data

We present a Bayesian approach for analyzing aggregate level sales data in a market with differentiated products. We consider the aggregate share model proposed by Berry et al. [Berry, Steven, Levinsohn, James, Pakes, Ariel, 1995. Automobile prices in market equilibrium. Econometrica. 63 (4), 841–890], which introduces a common demand shock into an aggregated random coefficient logit model. A full likelihood approach is possible with a specification of the distribution of the common demand shock. We introduce a reparameterization of the covariance matrix to improve the performance of the random walk Metropolis for covariance parameters. We illustrate the usefulness of our approach with both actual and simulated data. Sampling experiments show that our approach performs well relative to the GMM estimator even in the presence of a mis-specified shock distribution. We view our approach as useful for those who are willing to trade off one additional distributional assumption for increased efficiency in estimation.     

EIQ分析法在连锁经营配送中心拣货系统的应用

物流连锁经营配送中心将各类运输工具运来的成千上万种商品通过拣货系统进行迅速准确的分类．并将商品送到指定地点，通过EIQ分析法对配送中心的订单出货资料进行分析，为配送中心拣货系统规划提供一种简明有效的分析工具。找出客户订单的品项、数量与订购次数的特点。来进行配送中心存储、拣选等规划决策。     

射频识别技术在军事物流配送中的应用

现代化战争空前剧烈,军事物流保障任务更加复杂,责任更加重大。目前手工作业和条形码技术已经不能满足需求。而RFID技术可以弥补这种不足。论文从RFID技术入手,结合部队实际,提出了军械物资配送中出入库的设计方案,以及实现的功能。     

基于双层规划的综合运输网内承载运输量研究

提出了综合运输通道内运输量分配的双层规划模型．以便找到在综合交通运输通道内分配运输量的最优策略．从定量角度出发，既保证运输商使自己的运输费用最小，又能使上层部门优化分配运输量．使得综合交通运输通道内的系统经济效益最大。同时运用层次分析法，来计算多种交通方式之间的相对广义运输费用。最后给出一个算例说明了模型的应用。