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.

装运合并（SCL）是几个小负载的有目的组合，作为一个较大的货物。尽管订单交付的延迟可能会产生成本，但SCL可以导致运输规模的大量经济学，从而降低了整体系统成本。如果将注意力集中在最大持有时间（合并周期的长度）上，则不必降解对货物的接收者的服务。托运人希望选择适当的合并策略，该策略决定终止累积过程并派遣负载的正确时机。我们的新作品旨在提出和研究仅基于总运输重量和/或最大持有时间的典型策略。我们的新模型能够记录有关订单利益过程的更多信息（例如，单个订单的延迟），从而允许考虑取决于此类信息的策略。我们还将通过考虑马尔可夫的到来过程超出了典型的泊松分布，并通过在连续订单的到达与其权重之间结合潜在的相关性来提高模型的准确性。通过基质分析方法继续我们最近的成功，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：延迟罚款成本（等待客户的客户不足），这在等待时间严格增加。最终目标是确定一般情况下的最佳政策形式，并构建有效的算法以确定该最佳策略的参数，用于整合过程，涉及多种产品的订单，其运输成本和/或延迟量率可能会有所不同。 批号的问题旨在确定单个项目或几个项目的时间和补货量，以最大程度地降低总成本，同时满足需求需求。根据客户的订单，当这些物品分为家庭时，可以通过生产和分发来满足需求。通过家庭的联合协调认识到运输资源（如SCL）或供应链的制造部分共享。在生产背景下，我们在几个多产品家族的批量研究研究方面的研究是新的。这项工作还将阐明对从普通供应商订购的产品的协调库存控制。我们将探索各种大型大小问题的强大改革，并测试新的启发式方法以加快解决方案时间，并保持解决方案质量。 通行库存问题涉及车辆路由（客户在卡车进行交付时对客户进行测序）和股票供应商的管理人员为那些正在交付产品的客户。我们的研究允许在有利的情况下开发间接路线。这些服务于通过给定的杂交（CD）接收商品的逻辑组合的客户集。路线上的客户可能与车辆容量允许的范围一样多。考虑到客户的库存持有成本和管道库存。该主题以非平凡的方式扩展了申请人先前关于VMI（供应商托管库存）和交叉船的出版物。我们希望获得一般，近乎最佳的结果，以及一种有效的解决方案算法，用于包含几个CD的系统，其中私人车队在路线上向各种客户提供了来自多个供应商的不同产品。这项工作将代表最早的模型之一。