Competitive location and capacity decisions for firms serving time‐sensitive customers

In this article we explore how two competing firms locate and set capacities to serve time‐sensitive customers. Because customers are time‐sensitive, they may decline to place an order from either competitor if their expected waiting time is large. We develop a two‐stage game where firms set capacities and then locations, and show that three types of subgame perfect equilibria are possible: local monopoly (in which each customer is served by a single firm, but some customers may be left unserved), constrained local monopoly (in which firms serve the entire interval of customers but do not compete with each other), and constrained competition (in which firms also serve the entire interval of customers, but now compete for some customers). We perform a comparative statics analysis to illustrate differences in the equilibrium behavior of a duopolist and a coordinated monopolist. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

Continuous sampling plans for markov-dependent production processes

This article discusses the behavior of three continuous sampling plans: continuous sampling plan 1 (CSP 1) and continuous sampling plan 2 (CSP 2) developed by Dodge [5] and Dodge and Torrey [7], and multilevel continuous sampling plan 2 (MLP 2) developed by Lieberman and Solomon [11], when the quality of successive units in a continuous production process follows a two-state time-homogeneous Markov chain. We first derive the average outgoing quality (AOQ) expressions of these plans. Exact procedures for determining the average outgoing quality limit (AOQL) can be obtained only for CSP 1. For CSP 2 and MLP 2 plans, iterative procedures have been used to obtain the AOQL contours. For these plans, it is assumed that the serial correlation coefficient between the two consecutive random variables of the Markov chain is known. In addition, estimation procedures for the coefficient are given. We show that if the serial correlation coefficient of the Markov chain is positive (negative), the AOQL is increased (decreased) as compared to the case when the successive units in the production process follows a Bernoulli pattern. Let r denote the number of production units examined in succession which are found to be of good quality and k denote the inverse of the sampling fraction employed when quality is good. Then if r and k are sufficiently small, it is observed from the graph that, for small departures of the serial correlation coefficient from zero, the AOQL values do not differ significantly for each of the three plans; whereas for sufficiently large values of r and k, the AOQL values differ significantly. Various aspects of these plans, such as their operating characteristics 2 (OC 2) and the serial correlation coefficient, are discussed.     

A decomposition procedure for convex quadratic programs

This article deals with the solution of convex quadratic programs by iteratively solving a master problem and a subproblem as proposed previously by Sacher. The approach has the advantage that the subproblems are linear programs so that advantage can be taken of existing schemes for solving large linear problems. At each step in solving the master problem, a closed-form solution can be specified so that the procedure is well suited for solving large quadratic programs and can take advantage of the constraint structure.     

Production lot sizing under setup and worker learning

Previous lot-sizing models incorporating learning effects focus exclusively on worker learning. We extend these models to include the presence of setup learning, which occurs when setup costs exhibit a learning curve effect as a function of the number of lots produced. The joint worker/setup learning problem can be solved to optimality by dynamic programming. Computational experience indicates, however, that solution times are sensitive to certain problem parameters, such as the planning horizon and/or the presence of a lower bound on worker learning. We define a two-phase EOQ-based heuristic for the problem when total transmission of worker learning occurs. Numerical results show that the heuristic consistently generates solutions well within 1% of optimality.     

Multiple criteria decision making in the USSR: A survey

A brief historical overview of the development of multiple criteria decision making (MCDM) in the USSR during the last fifteen years is presented. Soviet MCDM research is reviewed. Several applications of MCDM methodology in the USSR are described. Long-term trends in the research and application of MCDM in the Soviet Union are discussed.     

Modeling the performance of a scanning radio communications sensor

A model which allows the prediction of long-term average report rates against an array of radio emitters by a scanning sensor is presented. The model is based on Markov renewal theory.     

Bounds and properties of the expected value of sample information for a project-selection problem

In this article we extend the work of Mehrez and Stulman [5] on the expected value of perfect information (EVPI) to the expected value of sample information (EVSI) for a class of economic problems dealing with the decision to reject or accept an investment project. It is shown that shifting the mean of the underlying a priori distribution of X, the project's monetary value from zero in either direction will decrease the associated EVSI of Y, the random sampled information. A theorem is then presented which gives an upper bound on the EVSI over all distributions of Y, as well as the structure of the posterior mean E[X|Y] for which this upper bound is achieved. Finally, the case where E[X|Y] is linear in Y is discussed and its performance compared with that of the optimal case.     

Defense Firms Adapting to Major Changes in the French R&D Funding System

The structural changes inside the French innovation system have impacted the role of defense firms since the late 1980s. Major changes have affected the defense budget and public R&D funding system in particular. The aim of this article is to understand French defense firms’ repositioning within the National Innovation System (NIS) based on an analysis of their R&D behavior over a long period of time (1987–2010). We show that French defense firms remain major players in the NIS and faced up to these major changes by adapting the funding of their R&D and their research priorities and rolling out new innovation capabilities. Additionally, they developed new innovation models to take advantage of new collaborative partnerships developed for civil and military markets.     

An Opportunity Structure for Terrorism: Moderate Leadership Departures in Nationalist Movements

Why does terrorist violence escalate from some ethnic groups but not others? According to theoretical insights, many groups endure conditions that should spur on terrorist campaigns, but in reality only some carry them out. In contrast to studies emphasising motivations, this article constructs a framework centred on opportunity structures that contributes to our understanding of the rise of terrorism waged along ethnic lines. It argues that beyond grievances or other motivations, terrorist campaigns develop from communities when moderate political leaders depart from their positions in nationalist movements, causing terrorists to fill the subsequent power vacuum, while little terrorism occurs when leaders do not relinquish the nationalist agenda. This argument is evaluated with evidence from the Tamil and Muslim cases in the context of the Sri Lankan Civil War. Tamil United Liberation Front leaders left the Tamil nationalist movement in the early 1980s, enabling the Liberation Tigers of Tamil Eelam’s rise to dominate the nationalist agenda for three decades, while the Sri Lanka Muslim Congress did not relinquish the Muslim cause, which in part precluded the normalisation of violence in the community.     

Towards a new national security policy for Canada

Canada is now at a crossroads unlike any other period in its history and needs to carefully consider which path to take. With the new Trudeau government comfortably ensconced since the defeat of the Harper government in the fall of 2015, a variety of competing interests have emerged in an attempt to turn Canadian policy back to a more nostalgic period of the 1970s that some see as preferable to the institutional lash-up that existed since the rolling out of the Canada First policy in the 2000s. That nostalgic period is, however, misunderstood both willfully for political purposes but also through a lack of historical context. Firmly rooting future actions in a blunt analysis of national interests is preferable to the alternative.