Rob Zuidwijk

Strategic response to EEE returns:: Product eco-design or new recovery processes?

In this paper we study how industry should strategically respond to imposed producer responsibility by regulation such as the WEEE-directive. Product eco-design covers both Design for Disassembly and Recovery (DfX) and Product Data Management (PDM). On the process side, X-ray technologies and Post-shredder Separation Techniques (PST) can also improve the overall efficiency of recovery strategies. We revisit the Roteb case on monitors published in some of our previous work and add characteristics to make it up-to-date. We develop four scenarios with each three different information levels on the disassembly Bill Of Material (dBOM) and on return quality, namely perfect information, partial information, and a scenario with no information. For the three information scenarios, we deploy different decision support models, namely an integer program in case of perfect information, a number of decision rules in case of partial information, and a default strategy in case of no information. Within each scenario, we carry out a sensitivity analysis on those operational parameters affected by the strategic choices mentioned. We conclude with recommendations to OEMs on strategic response related to recovery and elaborate on future research using our modeling approach in the EEE and other types of industry.

E-Enabled Closed-Loop Supply Chains

Information and Communication Technology can help companies realize new innovative business opportunities in the area of closed-loop supply chains. This article examines closed-loop supply chains from three perspectives: processes, customers, and products. Exploiting the possibilities of closed-loop supply chains involves handling uncertainties by providing adequate information. Information on recovery options for a product, product preferences of the customer, and the state of the product can be used to reduce uncertainty. Data that is retrieved from the closed-loop supply chain by new technologies can be transformed into management information in a systematic way. This article presents a framework to address uncertainty reduction strategies.

Double Counting in Supply Chain Carbon Footprinting

Carbon footprinting is a tool for firms to determine the total greenhouse gas GHG emissions associated with their supply chain or with a unit of final product or service. Carbon footprinting typically aims to identify where best to invest in emission reduction efforts, and/or to determine the proportion of total emissions that an individual firm is accountable for, whether financially and/or operationally. A major and underrecognized challenge in determining the appropriate allocation stems from the high degree to which GHG emissions are the result of joint efforts by multiple firms. We introduce a simple but general model of joint production of GHG emissions in general supply chains, decomposing the total footprint into processes, each of which can be influenced by any combination of firms. We analyze two main scenarios. In the first scenario, the social planner allocates emissions to individual firms and imposes a cost on them such as a carbon tax in proportion to the emissions allocated. In the second scenario, a carbon leader voluntarily agrees to offset all emissions in the entire supply chain and then contracts with individual firms to recoup part of the costs of those offsets. In both cases, we find that, to induce the optimal effort levels, the emissions need to be overallocated, even if the carbon tax is the true social cost of carbon. This is in contrast to the usual focus in the life-cycle assessment LCA and carbon footprinting literatures on avoiding double counting. Our work aims to lay the foundation for a framework to integrate the economics-and LCA-based perspectives on supply chain carbon footprinting.

Spare Parts Logistics and Installed Base Information

Many of the challenges in spare parts logistics emerge due to the combination of large service networks, and sporadic/slow-moving demand. Customer heterogeneity and stringent service deadlines entail further challenges. Meanwhile, high revenue rates in service operations motivate companies to invest and optimize the service logistics function. An important aspect of the spare parts logistics function is its ability to support customer-specific requirements with respect to service deadlines. To support customer specific operations, many companies are actively maintaining and utilizing installed base data during forecasting, planning and execution stages. In this paper, we highlight the potential economic value of installed base data for spare parts logistics. We also discuss various data quality issues that are associated with the use of installed base data and show that planning performance depends on the quality dimensions.

Port Inter-Organizational Information Systems: Capabilities to Service Global Supply Chains

This paper provides insights into the ways global sea ports are challenged by the need for managing complex information flows, given the developments in global supply chains. We argue that special port IT capabilities are needed to address these challenges by sharing information and planning and executing container transport in a collaborative way, establishing inter-organizational information architectures, and coordinating interests to successfully implement the technological infrastructures. We focus on the role of port community systems that support port communities in meeting the demands of global supply chains.

A Finer Aspect of Eigenvalue Distribution of Selfadjoint Band Toeplitz Matrices

The asymptotics of eigenvalues of Toeplitz operators has received a lot of attention in the mathematical literature and has been applied in several disciplines. This paper describes two such application disciplines and provides refinements of existing asymptotic results using new methods of proof. The following result is typical: Let

Directional and time-scale wavelet analysis

T(\varphi)

The Value of Information in Container Transport

be a selfadjoint band limited Toeplitz operator with a (real valued) symbol

Flexible Connections in Pesp Models for Cyclic Passenger Railway Timetabling

\varphi

Information and Communication Technology Enabling Reverse Logistics

, which is a nonconstant trigonometric polynomial. Consider finite truncations