The boomerang returns? Accounting for the impact of uncertainties on the dynamics of remanufacturing systems

Recent years have witnessed companies abandon traditional open-loop supply chain structures in favour of closed-loop variants, in a bid to mitigate environmental impacts and exploit economic opportunities. Central to the closed-loop paradigm is remanufacturing: the restoration of used products to useful life. While this operational model has huge potential to extend product life-cycles, the collection and recovery processes diminish the effectiveness of existing control mechanisms for open-loop systems. We systematically review the literature in the field of closed-loop supply chain dynamics, which explores the time-varying interactions of material and information flows in the different elements of remanufacturing supply chains. We supplement this with further reviews of what we call the three ‘pillars’ of such systems, i.e. forecasting, collection, and inventory and production control. This provides us with an interdisciplinary lens to investigate how a ‘boomerang’ effect (i.e. sale, consumption, and return processes) impacts on the behaviour of the closed-loop system and to understand how it can be controlled. To facilitate this, we contrast closed-loop supply chain dynamics research to the well-developed research in each pillar; explore how different disciplines have accommodated the supply, process, demand, and control uncertainties; and provide insights for future research on the dynamics of remanufacturing systems

Effective medical surplus recovery

We analyze not-for-profit Medical Surplus Recovery Organizations (MSROs) that manage the recovery of surplus (unused or donated) medical products to fulfill the needs of underserved healthcare facilities in the developing world. Our work is inspired by an award-winning North American non-governmental organization (NGO) that matches the uncertain supply of medical surplus with the receiving parties’ needs. In particular, this NGO adopts a recipient-driven resource allocation model, which grants recipients access to an inventory database, and each recipient selects products of limited availability to fill a container based on its preferences. We first develop a game theoretic model to investigate the effectiveness of this approach. This analysis suggests that the recipient-driven model may induce competition among recipients and lead to a loss in value provision through premature orders. Further, contrary to the common wisdom from traditional supply chains, full inventory visibility in our setting may accelerate premature orders and lead to loss of effectiveness. Accordingly, we identify operational mechanisms to help MSROs deal with this problem. These are: (i) appropriately selecting container capacities while limiting the inventory availability visible to recipients and increasing the acquisition volumes of supplies, (ii) eliminating recipient competition through exclusive single-recipient access to MSRO inventory, and (iii) focusing on learning recipient needs as opposed to providing them with supply information, and switching to a provider-driven resource allocation model. We use real data from the NGO by which the study was inspired and show that the proposed improvements can substantially increase the value provided to recipients

To what extent does the interest burden affect firm survival? Evidence from a panel of UK firms during the recent financial crisis

Using a panel of mainly unquoted UK firms over the period 2000–09, we document a significant effect of changes in the interest burden from debt-servicing on firm survival. The effect is found to be stronger during the recent financial crisis compared with more tranquil periods. Furthermore, the survival chances of bank-dependent, younger, and non-exporting firms are most affected by changes in the interest burden, especially during the crisis. Our results are robust to using different estimation methods and different interest burden measures They suggest that one way for policymakers to mitigate the effects of financial crises by limiting firm failures would be to prevent financing costs from rising, especially for those firms more likely to face liquidity constraints

Information visibility and its effect on supply chain dynamics

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Includes bibliographical references (p. 61-64).Supply chains are nonlinear dynamic systems, the control of which is complicated by long, variable delays in product and information flows. In this thesis, we present a novel framework for improving the visibility of information in supply chains by reducing the delays in information flow. We first analyze the growth and evolution of production and operations management software over the past three decades, and the current trends in their development, coupled with recent advances in radio frequency technology, wireless communications, data representation methods, and the internet. Information visibility is identified as one of the key elements for successful implementation of any such software. We analyze the dynamics of a supply chain under different scenarios of information visibility and forecasting decisions with the help of simulations. Possible improvements in supply chain costs are identified, provided information visibility. We propose a framework to achieve information visibility in the supply chain using radio frequency tags, tag readers, product identification codes, an object description language, and the internet.by Yogesh V. Joshi.S.M

How to Make the Most Productive Intervention in a Complex Economic System

Information about supply and demand propagates through supply chains in a queueing network with people and computers as batch information processors. As each batch processor delays propagation of information whilst pursuing optimal local decisions, the effect is delay and distortion of the information that is used to commit resources to actions in the supply chain. This thesis investigates the effect of delay and imperfect information as a source of error, to establish the case for change in research focus from optimal exploitation of physical constraints to optimal exploitation of information. In the context of real world supply chains, the thesis asks "How does one make the most productive intervention in a complex economic system?" and pursues a meta-intervention which perpetually minimises the discovered error-term. Evidence from literature indicates that agent-based modelling permits real-time peer-to-peer communication and distributed optimisation. Based on the literature the research project designs and develops an agent-based model which operates in real-time without batch-processes and can perform incremental multi-objective optimisation under realistic (chronologically progressive) conditions for decision making. The agent based model is then used to investigate two real-world supply chains, as case studies, which reveals a significant improvement of profitability and order-fulfilment. The thesis concludes that agent-based modelling is a very promising direction for "making the most productive intervention" as it reduces delay to a minimum. Finally it recommends that continuous improvement of decision making methods is a role better suited for humans, rather than operational decision making where computers cope much better with the high amount of detailed information

Price Flexibility in Channels of Distribution: Evidence from Scanner Data

In this study, we empirically examine the extent of price rigidity using a unique store-level time series data set - consisting of (i) actual retail transaction prices, (ii) actual wholesale transaction prices which represent both the retailers' costs and the prices received by manufacturers, and (iii) a measure of manufacturers' costs - for twelve goods in two widely used consumer product categories. We simultaneously examine the extent of price rigidity for each of the twelve products at both, final goods and intermediate goods levels. We study two notions of price rigidity employed in the existing literature: (i) the frequency of price changes, and (ii) the response of prices to exogenous cost changes. We find that retail prices exhibit remarkable flexibility in terms of both notions of price rigidity. i.e., they change frequently and they seem to respond quickly and fully to cost changes. Furthermore, we find that retail prices respond not just to their direct costs, but also to the upstream manufacturers' costs, which further reinforces the extent of the retail price flexibility. At the intermediate goods level of the market, in contrast, we find relatively more evidence of rigidity in the response of manufacturers prices to cost changes. This despite the fact that wholesale prices change frequently and therefore exhibit flexibility according to the first notion of price rigidity.Price Flexibility, Price Rigidity, Final Goods Market, Intermediate Goods Market, Stages of Processing, Structural VAR, Scanner Data, Transaction Price Data, Frequency of Price Changes, Price Response to Exogeneous Cost Changes, Retail Price, Wholesale Price, New Keynesian Macroeconomics, How Markets Clear, Time Series Analysis, Orange Juice, Orange Juice Frozen Concentrate, Futures Market

Price Adjustment at Multiproduct Retailers

We empirically study the price adjustment process at multiproduct retail stores. We use a unique store level data set for five large supermarket and one drugstore chains in the U.S., to document the exact process required to change prices. Our data set allows us to study this process in great detail, describing the exact procedure, stages, and steps undertaken during the price change process. We also discuss various aspects of the microeconomic environment in which the price adjustment decisions are made, factors affecting the price adjustment decisions, and firm-level implications of price adjustment decisions. Specifically, we examine the effects of the complexity of the price change process on the stores’ pricing strategy. We also study how the steps involved in the price change process, combined with the laws governing the retail price setting and adjustment, along with the competitive market structure of the retail grocery industry, influence the frequency of price changes. We also examine how the mistakes that occur in the price change process influence the actions taken by these multiproduct retailers. In particular, we study how these mistakes can make the stores vulnerable to civil law suits and penalties, and also damage their reputation. We also show how the mistakes can lead to stock outs or unwanted inventory accumulations. Finally, we discuss how retail stores try to minimize these negative effects of the price change mistakes.Cost of Price Adjustment, Price Adjustment Process, Menu Cost, Posted Prices, Multiproduct Retailer, Price rigidity, Sticky Prices, Frequency of Price Changes, Time Dependent Pricing, Retail Supermarket and Drugstore Chains

Enabling supply chain cooperation with information sharing

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division; in conjunction with the Leaders for Global Operations Program at MIT, 2009.Cataloged from PDF version of thesis.Includes bibliographical references (p. 74-77).Virtual Business System (VBS) is a system with software and hardware components designed by Raytheon employees to improve operational performance by facilitating and reinforcing lean behavior. It has helped contribute to four years in a row of twenty-percent yearly reductions in costs by providing near real-time metrics information, visibility into the details underlying those metrics, and publishing results to provide accountability for continuous improvement efforts. Originally designed for use in a manufacturing cell, its use has since expanded to include project management, engineering, quality, and other functions. This thesis examines how VBS has contributed to internal alignment at Raytheon and explores whether it can fulfill Raytheon's external supply chain coordination needs as well. VBS was successfully upgraded to allow supplier access over Citrix; the next step is to conduct a pilot implementation to test the system in practice. As a "homegrown" system, VBS can be made to do nearly anything, and in time could fulfill Raytheon's supply chain integration needs. In the near term, additional work is likely to be necessary in the areas of data access control, user interface, and extension from stand-alone system to a peer-to-peer information sharing network. The VBS team will also need to continue gathering executive sponsorship and support in order to motivate the necessary change in business processes. A number of lessons applicable to supply chain integration systems in general can be learned from the success of VBS.(cont.) These include: the importance of ensuring client control and security of the data; the potential gains made possible by sharing functionality in addition to data; the need to include information about improvement processes when sharing information; and the critical need that the application remain flexible and responsive to change in user needs.by Akiva Holzer.S.M.M.B.A