Alan J. Stenger

The impact of inventory and flow planning parameters on supply chain performance: An exploratory study

Abstract The primary objective of this paper is to study the impact of selected inventory parameters and management techniques on the performance of an expanded and comprehensive retail supply chain. Specifically, we study the sensitivity of supply chain performance to three inventory planning parameters: (i) the forecast error, (ii) the mode of communication between echelons, and (iii) the planning frequency. We achieve this by constructing a detailed simulation model and with data adapted from a case study which we were involved with. The studies conclude that all the three parameters have a significant effect on performance. Increasing forecasting errors and the re-planning frequency decreases service, return on investment, and increases cycle time. Using a mode of communication that facilitates exchange of information between echelons in the supply chain yields a higher level of service when compared to the scenario where the entities in different echelons plan material flows independently.

Integrating the use of computers in logistics education

An integrated paradigm of using multiple software programs in logistics education is proposed as an effective problem‐solving tool in addition to computer programming and spreadsheet modelling. Presents the essentials of logistics systems management and how each software program can be used individually and jointly to address logistics issues in detail. In the integrated paradigm, a Lotus 123 spreadsheet program is used as an integrator which works together with other software to facilitate student learning and to aid better decision making process. In‐class surveys show that the proposed approach is both effective and efficient in terms of getting the right results in less time. The approach is also realistic because the mixed mainframe and microcomputer operating environment and multiple software programs are being used by the business community.

Reducing inventories in a multi-echelon manufacturing firm A case study

Abstract The effective planning and control of inventories in multi-echelon operations continues to be difficult in modern manufacturing firms. Theoretical models tend to require substantial amounts of data and to make many restrictive assumptions, thus they generally are not often used in practical business situations. On the other hand, the simplistic rules of thumb and the lack of coordination between echelons (levels) typically found in many multi-echelon manufacturing situations frequently lead to excessive inventories both in the firm and throughout the supply chain. This paper presents the experience of the author in helping a firm identify the relative impact of the various determinants of inventories as a means of setting priorities for inventory reduction. The results lead to some interesting generalizations concerning practical ways of managing multi-echelon inventories. The paper first reviews the methods typically used by large multi-national firms to manage multi-echelon operations, and then proceeds to a description of the industrial situation dealt with. The remainder of the paper describes the modeling approach used to estimate inventory behavior under a variety of inventory reduction initiatives, the results of the study, and several new insights gleaned in the process.

Semi‐variable delivery routes and the efficiency of outbound logistics

Maintaining efficiency in despatching goods from a depot to geographically dispersed customers may require management at the depot to adjust its delivery routes daily if these customers’ demands fluctuate from day to day. One type of adjustment is to give drivers daily “skip lists” instructing them not to visit customers who have indicated that they do not need delivery on the day in question. This adjustment, which is appropriately referred to as semi‐variable routes, increases the depot’s outbound logistics productivity by eliminating some unnecessary travelling. Using extensive experimental data, develops a regression model that efficiently and accurately estimates this productivity increase, and illustrates how spreadsheets can be used as a decision support medium for using the model in pedagogical and applied settings. Confirms the model’s validity by standard model validation tests as well as by comparison with an existing model from previous research.

Commercially Available Software for Integrated Logistics Management

The importance and utilization of information systems in the achievement of integrated service response and supply chain logistics has been shown by several recent studies. Practitioners need to have an understanding of the existance and capability of commercially available software options for integrated logistics management. For educators it is imperative that knowledge about the functioning of current software is taught in a manner that gives students an appreciation of the available techniques and software, along with the realization of the difficulty of implementation. This article provides practitioners and educators with an empirical assessment of the available logistics software as it applies to integrated hierarchical planning.

Managing information in the supply chain to enhance customer service and build relationships

Information technology has allowed motor carriers to enhance the visibility of the service process and to provide shippers with an incentive for shipper/carrier partnerships. In todays business environment, information technology offers customers the opportunity to take an active part in the service process, without actually being present in the service setting. This is important for the transport industry since it represents a service characterised by low customer contact and little information exchange. In an attempt to overcome these problems, motor carriers have installed satellite communications systems to increase customer contact and interaction that will aid in developing long-term relationships and result in better coordination and less inventory throughout the supply chain. The high-tech industry and case studies are used to illustrate these premises. An inventory-theoretic model of transportation choice is developed and future research directions are discussed.

An analysis of the impact of the energy shortage on business logistics systems, and its implication for freight transport

Abstract The energy crisis will probably affect business logistics systems in the U.S. economy in two ways: cost and service relationships between the various modes of freight transportation may change (as carriers seek to compensate for higher fuel prices and fuel shortages) or aggregate levels of production may change (either because of fuel and raw material shortages or reduced demand). As logistics decision makers seek to compensate for these changes, their transportation requirements may also shift. These shifts will not necessarily result in an improvement in energy utilization in the freight sector of the economy. Thus government policies may need to be developed to counteract the effect of such changes. This paper discusses these potential shifts, with specific reference to rail-truck competition, and recommends some changes in government policies in light of these conclusions.