(R.Q) inventory problem with unknown mean demand and learning

We address a single product, continuous review model with stationary Poisson demand. Such a model has been effectively studied when mean demand is known. However, we are concerned with managing new items for which only a Bayesian prior distribution on the mean is available. As demand occurs, the prior is updated and our control parameters are revised. These include the reorder point (R) and reorder quantity (Q). Deemer, taking a clue from some earlier RAND work, suggested using a model appropriate for known mean, but using a Compound Poisson distribution for demand rather than Poisson to reflect uncertainty about the mean. Brown and Rogers also used this approach but within a periodic review context. In this paper we show how to compute optimum reorder points for a special problem closely related to the problem of real interest. In terms of the real problem, subject to a qualification to be discussed, the reorder points found are upper bounds for the optimum. At the same time, the reorder points found can never exceed those found by the Compound Poisson (Deemer) approach. And they can be smaller than those found when there is no uncertainty about the mean. As a check, the Compound Poisson and proposed approach are compared by simulation.     

Stationary (s,s) policies for a finite horizon

In the finite-horizon stochastic (s, S) inventory model with periodic review the parameters of the optimal policy generally vary with the length of the horizon. A stationary policy, however, is easier to implement and may be easier to calculate. This paper studies optimal stationary policies for a finite horizon and relates them to optimal policies through their relation to optimal stationary policies for an infinite horizon.     

On a search for a moving target

We consider the problem of searching for a target that moves in discrete time and space according to some Markovian process. At each time, a searcher attempts to detect the target. If the searcher's action at each time is such as to maximize his chances of immediate detection, we call his strategy “myopic.” We provide a computationally useful necessary condition for optimality, and use it to provide an example wherein the myopic strategy is not optimal.     

Heuristic solution to a discrete collection model

A discrete time Collection Model is formulated, involving the completion of a touring objective on a network with stochastic node states. Heuristic touring strategies are constructed, there being as yet inadequate analytic results for its optimal solution. Effectiveness of the heuristics is assessed by comparing expected tour times under the heuristics with expected tour times given perfect information. A branch and bound algorithm is presented for computing the perfect information tour times.     

A note on eoq under fund constraints

An algorithm is developed to modify the Wilson Q to account for a short-term expenditure constraint over a catalog of items. Representative results are shown and generalizations made.     

Smart Power and Military Force: An Introduction

Abstract

Smart power is comprised of two elements: the quest for building society among states and between states and non-state actors; as well as the desire for cleaner forms of power projection. This special issue explores how states continue to fumble over achieving the optimum mix of hard and soft power across several country cases and themed articles. This set of contributions suggests that smart power is not unlike a ‘Swiss Army Knife’ analogy: multifunctional and challenging to choose the right combination of ideational and material tools.     

The insurgency of the Vendée

The insurrection in the Vendée combined open warfare with the methods of petite guerre, ambushing French republican soldiers and cutting their supply lines to Paris. These tactics, when combined with the hatreds generated by a civil war, go far to explain to the cruelty of the conflict in the west and the depth of the hatreds it engendered. In republican eyes the use of guerrilla tactics was unjust and illegitimate, and they denounced their adversaries as common criminals and brigands, portraying them as backward, superstitious, even as subhuman, and in the process justified the savage repression they unleashed against them.     

THE EFFECT OF 9/11 ON US EXPORTS AND IMPORTS OF TOURISM

Several studies have investigated whether the terrorist attacks of September 11, 2001, have had an ongoing or merely transitory effect on US trade in tourism. All conclude in favor of the latter. However, limitations in either the data and/or methodology employed by these studies give cause to query their findings. The present study avoids these limitations and finds strong evidence that, once other factors are held constant, real US exports and imports of tourism have both remained significantly below their pre‐2001 level.     

A novel method for determination of lethal radius for high-explosive artillery projectiles

A new model has been defined that enables the estimation of the lethal radius (radius of efficiency) of HE (High Explosive) artillery projectiles against human targets. The model is made of several modules: CAD (Computer Aided Design) modeling, fragment mass distribution estimation, fragment initial velocity prediction, fragment trajectory calculation, effective fragment density estimation, and high explosive projectile lethal radius estimation. The results were compared with the experimental results obtained based on tests in the arena used in our country, and the agreement of the results was good. This model can be used in any terminal-ballistics scenario for high explosive projectiles since it is general, para-metric, fast and relatively easy to implement.