Operations Research articles from May 2005

Operations Research archives from May 2005

In this issue.(Assessing Protein Structure Similarity)(Risk Taking When the Downside Matters)(Exact Approaches to Forest Harvesting)
May 1, 2005... Assessing Protein Structure Similarity In biology, the protein structure alignment problem answers the question of how similar two proteins are. Because a protein's function is intrinsically tied to its structure, many biologists believe...

Optimal protein structure alignment using maximum cliques.
May 1, 2005... In biology, the protein structure alignment problem answers the question of how similar two proteins are. Proteins with strong physical similarities in their tertiary (folded) structure often have similar functions, so understanding physical...

Discrete-time financial planning models under loss-averse preferences.
May 1, 2005... We consider a dynamic asset allocation problem formulated as a mean-shortfall model in discrete time. A characterization of the solution is derived analytically under general distributional assumptions for serially independent risky returns....

Revenue management for parallel flights with customer-choice behavior.
May 1, 2005... We consider the simultaneous seat-inventory control of a set of parallel flights between a common origin and destination with dynamic customer choice among the flights. We formulate the problem as an extension of the classic multiperiod,...

Clustering sensors in wireless ad hoc networks operating in a threat environment.
May 1, 2005... Sensors in a data fusion environment over hostile territory are geographically dispersed and change location with time. To collect and process data from these sensors, an equally flexible network of fusion beds (i.e., clusterheads) is required....

Patient choice in kidney allocation: a sequential stochastic assignment model.
May 1, 2005... This paper investigates the effect of patient choice on kidney allocation using the following sequential stochastic assignment model. There are n transplant patients to be allocated n kidneys that will arrive sequentially. Each patient and each...

Optimization of influenza vaccine selection.
May 1, 2005... The World Health Organization (WHO) recommends which strains of influenza to include in each year's vaccine to countries around the globe. The current WHO strategy attempts to match the vaccine strains with the expected upcoming epidemic...

A fictitious play approach to large-scale optimization.
May 1, 2005... In this paper, we investigate the properties of the sampled version of the fictitious play algorithm, familiar from game theory, for games with identical payoffs, and propose a heuristic based on fictitious play as a solution procedure for...

Harvest scheduling subject to maximum area restrictions: exploring exact approaches.
May 1, 2005... We consider a spatial problem arising in forest harvesting. For regulatory reasons, blocks harvested should not exceed a certain total area, typically 49 hectares. Traditionally, this problem, called the adjacency problem, has been approached...

A multiperiod dynamic model of taxi services with endogenous service intensity.
May 1, 2005... This paper presents a spatially aggregated multiperiod taxi service model with endogenous service intensity. The whole day service period is divided into a number of subperiods; during each subperiod, taxi supply and customer demand...

Throughput maximization for tandem lines with two stations and flexible servers.
May 1, 2005... For a Markovian queueing network with two stations in tandem, finite intermediate buffer, and M flexible servers, we study how the servers should be assigned dynamically to stations to obtain optimal long-run average throughput. We assume that...

Resource flexibility with responsive pricing.
May 1, 2005... This article studies two types of flexibility used by firms to better respond to uncertain market conditions: resource flexibility and responsive pricing. We consider a situation in which a single flexible resource can be used to satisfy two...

Fitting time-series input processes for simulation.
May 1, 2005... Providing accurate and automated input-modeling support is one of the challenging problems in the application of computer simulation of stochastic systems. The models incorporated in current input-modeling software packages often fall short...

Anisogamy, expenditure of reproductive effort, and the optimality of having two sexes.
May 1, 2005... No good formal arguments exist for a central question in biology: Why, in species that have sexual reproduction, are there usually only "males" and "females"? We present a nonlinear optimization model that supports the conclusion that having...

A note on convexity of the expected delay cost in single-server queues.
May 1, 2005... In this note, we show that the expected delay cost for a G/G/1 queue is not necessarily convex in the arrival rate as sometimes claimed in the literature. We can prove, however, that the total expected delay cost rate is convex in the arrival...