In the past few years, increasing numbers of automatic warehousing systems using computer-controlled stacker cranes have been installed. Our research concerns the scientific scheduling and design of these systems. There are three elements to scheduling: the assignment of multiple items to the same pallet (Pallet Assignment); the assignment of pallet loads to storage locations (Storage Assignment); and rules for sequencing storage and retrieve requests (Interleaving). This paper deals with optimal storage assignment. Results are obtained which compare the operating performance of three storage assignment rules: random assignment, which is similar to the closest-open-location rule used by many currently operating systems; full turnover-based assignment: and class-based turnover assignment. It is shown that significant reductions in crane travel time (and distance) are obtainable from turnover-based rules. These improvements can, under certain circumstances, be directly translated into increased throughput capacity for existing systems, and may be used to alter the design (e.g., size and number of racks, speed of cranes, etc.) of proposed systems in order to achieve a more desirable system balance between throughput and storage capacity.

This paper presents an exploratory investigation of the manufacturing/marketing (hereafter M/M) interface. Drawing on the literature and prior empirical work in M/M strategies, we propose a path model for assessing the mediating impact of the M/M interface harmony-the functions' ability to work together-on M/M morale and business performance. Using two convenience samples of executives, we empirically test the direct and indirect influence of predisposing factors (antecedents) and performance outcomes (consequences) that are expected theoretically to influence or be influenced by M/M interface harmony.We find that 11 of the 13 hypothesized direct effects are significant at the 0.012 level or below; and attesting to the mediating influence of the M/M ability to work together, 11 of the 12 indirect effects were significant at the 0.02 level or below. Increasing the emphasis on the importance of marketing or manufacturing, or both, improves the ability of both functions to work harmoniously, which in turn impacts M/M morale. Interfunctional harmony appears to have a stronger influence on each function's morale than the importance attached to that function, ceteris paribus. Contrary to conventional wisdom, the study provides insight on the distinctive roles whereby marketing and manufacturing functions influence performance. Marketing acts to improve competitive position and profitability through the mediating influence of M/M interface harmony and improved marketing morale. However, manufacturing morale was not shown to be a significant factor impacting performance. Rather, emphasis on manufacturing impacts competitive position directly, as indicated by the resource-based view of manufacturing strategy. This exploratory study provides new empirical evidence that the M/M interface harmony, as expressed by the functions' ability to work together, matters significantly to business outcomes directly and indirectly.

This paper extends work previously reported on storage assignment rules for automatic warehousing systems to include interleaving; that is, the sequencing of storage and retrieve requests. Using both continuous analytical models and discrete evaluation procedures, this paper compares the operating performance of several storage assignment/interleaving policies. The results indicate that significant reductions in crane travel time (and distance) are obtainable in some real-world and/or previously modeled situations via the proposed storage assignment/interleaving policies. These reductions may be directly translated into increased throughput capacity for existing systems. The storage assignment/interleaving policies may also be used to improve the design of proposed systems to achieve a more desirable balance between throughput and storage capacity. Although the system examined is a high-rise automatic warehouse, the results presented have implications for the warehousing function in general.

Analyzing the proliferation of item‐level RFID, recent studies have identified the cost sharing of the technology as a gating issue. Various qualitative studies have predicted that conflict will arise, in particular in decentralized supply chains, from the fact that the benefits and the costs resulting from item‐level RFID are not symmetrically distributed among supply chain partners. To contribute to a better understanding of this situation, we consider a supply chain with one manufacturer and one retailer. Within the context of this retail supply chain, we present analytic models of the benefits of item‐level RFID to both supply chain partners. We examine both the case of a dominant manufacturer as well as the case of a dominant retailer, and we analyze the results of an introduction of item‐level RFID to such a supply chain depending on these market power characteristics. Under each scenario, we show how the cost of item‐level RFID should be allocated among supply chain partners such that supply chain profit is optimized.

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This paper studies the impact of logistics performance on global bilateral trade. Taking a supply chain perspective, logistics performance refers to cost, time, and complexity in accomplishing import and export activities. We draw on a data set compiled by the World Bank containing specific quantitative metrics of logistics performance in terms of time, cost, and variability in time. Numerous researchers have shown that logistics performance is statistically significantly related to the volume of bilateral trade. Our research calibrates the impact of specific improvements in logistics performance (time, cost, and reliability) on increased trade. Our findings can spur public and private agencies that have direct or indirect influence over logistics performance to focus attention on altering the most relevant aspects of logistics performance to improve their country's ability to compete in today's global economy. Moreover, as our logistics metrics are directly related to operational performance, countries can use these metrics to target actions to improve logistics and monitor their progress.

A sequential decision problem is partitioned into two parts: a stochastic model describing the transition probability density function of the state variable, and a separate framework of decision choices and payoffs. If a particular sequential decision problem is a recurring one, then there may often exist human forecasters who generate quantitative forecasts at each decision stage. In those eases where construction of a mathematical model for predictive purposes is difficult, we may consider using the forecasts and forecast revisions provided by the existing forecasting mechanism as the state variable. The paper considers a specific class of problems in which improved forecasts of some unknown quantity are available before each decision stage. A small number of actual forecasters are studied through analysis of historical data to see whether the data-generating process for forecast changes is quasi-Markovian. The data are generally, although not entirely, consistent with the hypothesis that ratios of successive forecasts are independent variates; their distribution appears to be conditionally Lognormal. Some possible reasons for these results are explored. In cases where the hypothesis holds, a dynamic programming approach to the sequential decision problem may be used to provide optimal decision rules. The usefulness of the approach is illustrated with a numerical example involving crop planning, and the example is extended to explore the effects of using the methodology when the required assumptions do not hold.

Every CEO must always be concerned with the competition. In today's economy the battlefield is shifting from individual company performance to what we call Supply Chain Performance. Supply Chain Performance refers to the extended supply chain's activities in meeting endcustomer requirements, including product availability, on-time delivery, and all the necessary inventory and capacity in the supply chain to deliver that performance in a responsive manner. Supply Chain Performance crosses company boundaries since it includes basic materials, components, subassemblies and finished products, and distribution through various channels to the end customer. It also crosses traditional functional organization lines such as procurement, manufacturing, distribution, marketing & sales, and research & development.To win in the new environment, supply chains need continuous improvement. To achieve this we need performance measures, or "metrics," which support global Supply Chain Performance improvements rather than narrow company-specific or function-specific (silo) metrics which inhibit chain-wide improvements. We describe a number of supply chain performance measures that are expressly designed to support and monitor Supply Chain Performance improvements across the supply chain and illustrate the shortcomings of several common metrics.Charlie slammed the door on the way out of his boss's office. As operations manager for a major aluminum processing facility, he was proud of the fact that he had in past months achieved significantly high production figures for high margin specialty milled orders. But his boss had just berated him for producing fewer tons of low margin aluminum than budgeted. Charlie was a victim of a "bad'' performance measure or metric. Raw tonnage is an inappropriate measure of supply chain performance for a diverse product line where gross margin per ton varies considerably. The use of "bad'' metrics can be a major impediment to the implementation of effective integrated supply chain management in today's highly competitive business environment.