Flexible supply contracts for short life‐cycle goods: The buyer's perspective

In this paper we analyze a two‐period supply contract which allows for order adjustment by the buyer. The buyer is required to place orders for two periods. After observing initial demand, the buyer is then allowed to adjust the second order, paying a per unit order adjustment penalty. We describe the optimal behavior of the buyer under such a contract, both in determining the initial order quantities and in subsequently adjusting the order. We compare the solution to a contract where no adjustment is allowed and to the case where adjustment is allowed without penalty. We demonstrate that flexible contracts can reduce the potentially negative effect of correlation of demand between two periods. Further, we investigate how the duration of the first period vis‐à‐vis the second period affects the profitability of the buyer as a function of the degree of correlation. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 25–45, 2002; DOI 10.1002/nav.10002     

Information sharing in multinational security and military operations. Why and why not? With whom and with whom not?

Military operations increasingly require cooperation between agencies within the same nation, but also collaboration with security and military organizations internationally. Throughout history multinational military cooperation has often been an appropriate way to conduct major operations; national manpower and material resources are generally insufficient to address the demands of missions worldwide. The desire to optimize the use of scarce research and development and investment capabilities, the need for international legitimacy and political support, and the fact that today’s risks transcend national borders, have rendered multinational cooperation in the security domain unavoidable. With joint operations comes the requirement for multi-partner- and multinational information sharing. However, information sharing has both advantages and costs, and is subject to both enabling factors as well as barriers. This paper reflects on theories, both classical and current, as well as empirical case studies, to examine the pros and cons of multinational information sharing, and the factors that conduce or interfere with the transmission and the receipt of intelligence. The importance of a holistic approach and of learning lessons learned are two key lessons gleaned from the analysis, along with an emphasis on developing both the organizational and the interpersonal enablers of information sharing.     

Linking a throughput simulation to a systems dynamics simulation to assess the utility of a US Navy foreign humanitarian aid mission

The success of any humanitarian aid mission is generally measured by the timeliness of critical supplies that are delivered to the affected area. However, a more interesting analysis may be to determine the effect of the aid on the overall satisfaction of the local population. The authors' research focused on the delivery of humanitarian aid to a notional region that was decimated by flooding with ships, landing craft and security personnel provided by the US Navy and Marines. While the research effort addressed naval force structure, the focus of the research was: (1) to assess different delivery methods for the aid; and (2) to determine how the aid delivery impacted the overall satisfaction of the local population. To examine both concerns, two simulation models were developed, with one examining the throughput of aid delivered during the operation, and the other the satisfaction of the population based on the humanitarian aid effort.     

Exact algorithms for integrated facility location and production planning problems

We consider a class of facility location problems with a time dimension, which requires assigning every customer to a supply facility in each of a finite number of periods. Each facility must meet all assigned customer demand in every period at a minimum cost via its production and inventory decisions. We provide exact branch‐and‐price algorithms for this class of problems and several important variants. The corresponding pricing problem takes the form of an interesting class of production planning and order selection problems. This problem class requires selecting a set of orders that maximizes profit, defined as the revenue from selected orders minus production‐planning‐related costs incurred in fulfilling the selected orders. We provide polynomial‐time dynamic programming algorithms for this class of pricing problems, as well as for generalizations thereof. Computational testing indicates the advantage of our branch‐and‐price algorithm over various approaches that use commercial software packages. These tests also highlight the significant cost savings possible from integrating location with production and inventory decisions and demonstrate that the problem is rather insensitive to forecast errors associated with the demand streams. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

The United States Coast Guard Computer-Assisted Search Planning system (CASP)

This paper provides an overview of the Computer-Assisted Search Planning (CASP) system developed for the United States Coast Guard. The CASP information processing methodology is based upon Monte Carlo simulation to obtain an initial probability distribution for target location and to update this distribution to account for drift due to currents and winds. A multiple scenario approach is employed to generate the initial probability distribution. Bayesian updating is used to reflect negative information obtained from unsuccessful search. The principal output of the CASP system is a sequence of probability “maps” which display the current target location probability distributions throughout the time period of interest. CASP also provides guidance for allocating search effort based upon optimal search theory.     

A heuristic procedure for allocating tasks in fault-tolerant distributed computer systems

One way of achieving the increased levels of system reliability and availability demanded by critical computer-based control systems is through the use of fault-tolerant distributed computer systems. This article addresses the problem of allocating a set of m tasks among a set of n processors in a manner that will satisfy various task assignment, system capacity, and task scheduling constraints while balancing the workload across processors. We discuss problem background, problem formulation, and a known heuristic procedure for the problem. A new solution-improving heuristic procedure is introduced, and computational experience with the heuristics is presented. With only a modest increase in the amount of computational effort, the new procedure is demonstrated to improve dramatically solution quality as well as obtain near-optimal solutions to the test problems.