Algorithms and heuristics for variable-yield lot sizing

We consider the multiperiod lot-sizing problem in which the production yield (the proportion of usable goods) is variable according to a known probability distribution. We review two economic order quantity (EOQ) models for the stationary demand continuous-time problem and derive an EOQ model when the production yield follows a binomial distribution and backlogging of demand is permitted. A dynamic programming algorithm for an arbitrary sequence of demand requirements is presented. Heuristics based on both the EOQ model and appropriate modification of the underlying perfect-yield lot-sizing policies are discussed, and extensive computational evaluation of these heuristics is presented. Two of these heuristics are then modified to include the notion of supply safety stock. The modified heuristics consistently produce near-optimal lot-sizing policies for problems with stationary and time-varying demands.     

Troubled triangle: Russia,Ukraine and the United States

A potentially productive triangular arrangement among Russia, Ukraine, and the United States emerged in 1994 from efforts to constrain nuclear weapons diffusion. By 2001, this promising initiative was nearly moribund, owing to the inability or unwillingness of the parties to fulfill the commitments of subsequent agreements. The domestic and external causes of this failure are many and clear. Yet the advantages to each of reengaging in a trilateral relationship are also plain. This means fulfilling their unfinished agenda by learning from past mistakes, adopting realistic premises and goals, and pursuing ‘bottom up’ as well as ‘top down’ strategies.     

International Involvement in Restructuring and Creating Security Forces: The Case of Haiti

The controversy over banning landmines in the past decade has removed matters of military technical expertise to the purview of civilian interest groups. According to a Huntingtonian perspective, this could be an indicator of unhealthy civil-military relations. Evidence of this includes political leaders' disregard of senior military advice and the initiation of a program to develop landmine alternatives after having already committed to banning them. The desire to ban landmines may represent a pragmatic revision of pacifist attempts to ban warfare altogether. Because of the development of self-destructing or deactivating mines, the landmine ban movement intrudes on technical military matters without redeeming humanitarian value. This intrusion may have further ramifications for civil-military relations.     

Did the Panamanian Defense Forces conduct infiltration operations at the Arraijan Tank Farm in 1988?

This article reviews the circumstances surrounding a relatively obscure and almost forgotten US Marine Corps and Army security enhancement operation undertaken in Panama that commenced in early April of 1988. Marines were sent to Panama to protect oil and ammunition storage facilities from potential saboteurs. By April 1989 they had reported sighting armed, uniformed intruders on at least 43 occasions and receiving gunfire or discharging their own weapons during 16 incidents. Yet despite the repeated barrages of small arms fire over the course of a year, they failed to recover enemy ammunition, bodies or body parts and their own equipment and positions displayed no signs of suffering from hostile fire. This article analyzes the events from the point of view of a veteran of the operation and highlights the role that psychological operations may have played in generating the situation.     

INDIA AND THE NEW LOOK OF U.S. NONPROLIFERATION POLICY

U.S. nuclear export policy has undergone major transformations since 1945, and the most recent change, as expressed in the July 18, 2005, India-U.S. Joint Statement, represents an especially significant shift in policy. The document reverses more than a quarter century of U.S. declaratory policy, suggesting that the current U.S. administration regards nuclear proliferation to be both inevitable and not necessarily a bad thing. This article investigates this policy shift, looking at the history of U.S. nuclear export policy and the potential ramifications of the new policy on the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). The author also touches on the potential effects of the Joint Statement on Indian-Pakistani relations. Finally, it is suggested that it is not too late for India and the United States to change the new policy with more consideration for the NPT and the Nuclear Suppliers Group Initiative.     

Defense Expenditure and Income Inequality: Evidence on Co-integration and Causality for China

There are conflicting views as to the relationship between a nation’s defense expenditure (DE) and its population’s income inequality (INEQ). DE, always an important part of government budget, can easily crowd out transfer payments, necessary to improve INEQ; however, these payments may also create a demand that may raise the income levels of the lower income earners. Consequently, the relationship between DE and INEQ is an important question. This paper examines the relationship between DE and INEQ in China for the period of 1989–2012. Utilizing basic cointegration and causality tests, our objective is to add to the literature by providing evidence that China’s DE, in fact, do have an impact on INEQ.     

ON ETHNIC CONFLICT AND THE ORIGINS OF TRANSNATIONAL TERRORISM

Using the ITERATE dataset, we explore the origins of transnational terrorist activity, from 1982 through 1997, in 118 countries. We model terrorism, not as a function of a nation’s ethnic, religious or linguistic fractionalization, but as an independent measure of perceived ethnic tensions. When we control for institutional quality, evidence that political rights and civil liberties mitigate the terrorism‐producing effects of ethnic tensions exists only since 1990. Economic freedoms, on the other hand, robustly reduce the number of terrorist attacks originating in ethnically tense societies.     

Rendez‐vous search on a rectangular lattice

In a rendez‐vous search two or more teams called seekers try to minimize the time needed to find each other. In this paper, we consider s seekers in a rectangular lattice of locations where each knows the configuration of the lattice, the distribution of the seekers at time 0, and its own location, but not the location of any other. We measure time discretely, in turns. A meeting takes place when the two seekers reach the same point or adjacent points. The main result is that for any dimension of lattice, any initial distribution of seekers there are optimal strategies for the seekers that converge (in a way we shall make clear) to a center. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007