Logistics and Transportation in Supply Chains

供应链中的物流与运输

• 批准号: RGPIN-2014-04277
• 负责人: Bookbinder, James
• 金额: $ 1.6万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=610937
• 关键词: Logistics; Transportation; Supply; Chains

SHIPMENT CONSOLIDATION (SCL) is the purposeful combination of several small loads, for dispatch together, as a single larger shipment. Although delay of order deliveries may incur a cost, SCL can lead to significant economies of scale in transportation, thus reducing the overall system cost. Service to the receiver of the goods need not be degraded, if attention is paid to the maximum holding time (length of the consolidation cycle). The shipper wishes to select an appropriate consolidation policy that determines the right moment to terminate the accumulation process and dispatch a load. Our new work aims to propose and study policies that are more general than the typical ones that are based solely upon the aggregate shipment weight and/or the maximum holding time. Our new models are capable of recording more information about the order-accumulation process (e.g. delays of individual orders), thus permitting consideration of policies dependent on such information. We will also improve the accuracy of our models by considering Markovian arrival processes that go beyond the typically-assumed Poisson distribution, and by incorporating potential correlations between the arrivals of consecutive orders and their weights. Continuing our recent success with the Matrix-Analytic method, we will develop efficient solution techniques to obtain accurate results. We will employ a more realistic cost structure: a delay penalty cost (customer disutility of waiting) that is strictly increasing in that waiting time. The ultimate goals are to identify the form of the optimal policy for the general case, and to construct efficient algorithms to determine the parameters of that optimal policy, for a consolidation process involving orders of multiple products whose transport costs and/or delay-penalty rates may differ. LOT-SIZING PROBLEMS seek to determine the timing and replenishment quantities, of a single item or of several items, to minimize total costs while meeting demand requirements. Demand, based on orders from customers, can be satisfied through the production and distribution when those items are grouped into families. The joint coordination via families recognizes the sharing of a resource in transportation (as in SCL) or in the manufacturing portion of the supply chain. Our research in the study of lot-sizing of several multi-product families is new in the production context. This work will also shed light on coordinated inventory control of products ordered from a common supplier. We will explore various strong reformulations for the multi-family lot-sizing problem, and test new heuristics to speed up solution times, maintaining solution quality. THE INVENTORY-ROUTING PROBLEM concerns both vehicle routing (the sequencing of customers in making deliveries by truck) and the management by the vendor of stocks for those customers whose products are being delivered. Our research allows, when advantageous, the development of indirect routes. These serve logically-grouped sets of customers that receive goods through a given cross-dock (CD). There can be as many customers on the routes as permitted by vehicle capacity. Both the inventory holding costs at customers and the pipeline stocks are considered. This theme extends, in a non-trivial way, the applicant’s previous publications on VMI (Vendor Managed Inventory) and cross-docking. We hope to obtain general, provably near-optimal results, and an efficient solution algorithm, for a system containing several CDs in which distinct products from multiple suppliers are delivered by a private fleet on routes to various customers. This work will represent one of the very first such models.

装运拼装 (SCL) 是有目的地组合多个小货物，作为单个较大的装运一起发货。尽管订单交付延迟可能会产生成本，但 SCL 可以带来显着的运输规模经济，从而减少整个系统的规模。如果注意最大保留时间（拼箱周期的长度），则无需降低对货物接收方的服务成本。并派遣一个我们的新工作旨在提出和研究比仅基于总发货重量和/或最大持有时间的典型政策更通用的政策，我们的新模型能够记录有关订单累积的更多信息。过程（例如单个订单的延迟），从而允许考虑依赖于此类信息的政策。我们还将通过考虑超出通常假设的泊松分布的马尔可夫到达过程，并通过纳入之间的潜在相关性来提高模型的准确性。连续订单到达继续我们最近在矩阵分析方法方面取得的成功，我们将开发有效的解决方案技术以获得准确的结果，我们将采用更现实的成本结构：严格增加的延迟惩罚成本（客户等待的不利影响）。最终目标是确定一般情况下最优策略的形式整合，并构建有效的算法来确定该最优策略的参数，以处理具有运输成本和/或延迟的多种产品的订单。 - 罚款率可能有所不同。 批量问题旨在确定单个项目或多个项目的时间和补货数量，以最大限度地降低总成本，同时满足需求，基于客户的订单，当这些项目可以通过生产和分配来满足时。通过系列进行联合协调可实现运输（如 SCL）或供应链的制造部分的资源共享。我们对多个多产品系列的批量大小的研究是新的。在生产环境中。这项工作还将阐明从共同供应商订购的产品的协调库存控制。我们将探索针对多户批量问题的各种强有力的重新制定，并测试新的启发式方法以加快解决时间，保持解决方案质量。 库存路线问题涉及车辆路线（通过卡车送货的客户顺序）和供应商对正在交付产品的客户的库存管理，我们的研究允许在有利的情况下开发间接路线。这些服务按逻辑分组，通过给定的交叉转运 (CD) 接收货物。路线上可以有车辆容量允许的尽可能多的客户，同时考虑客户的库存持有成本和管道库存。这个主题延伸到以非平凡的方式，申请人之前关于VMI（供应商管理库存）和越库对接的出版物我们希望获得通用的、可证明接近最优的结果以及有效的解决算法，用于包含多个CD的系统，其中来自不同的产品。私人车队将多个供应商运送到不同的客户手中，这项工作将是最早的此类模型之一。