Field test and probabilistic analysis of irregular steel debris casualty risks from a person-borne improvised explosive device

Person-borne improvised explosive devices (PBIEDs) are often used in terrorist attacks in Western countries. This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard. An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour, including positions, velocity, and trajectory angles. These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis. In the probabilistic analyses a probability of fatality or serious injury was computed. Based on the results presented, many practical conclusions can be drawn, for instance, regarding safe evacuation distances if a person were exposed to a suspected PBIED.     

Improvement of VIS and IR camouflage properties by impregnating cotton fabric with PVB/IF-WS2

In order to examine the possibility to improve its camouflage properties standard cotton fabric with camouflage print was impregnated with poly(vinyl butyral), PVB and fullerene-like nanoparticles of tungsten disulfide, PVB/IF-WS₂. FTIR analysis excluded any possible chemical interaction of IF-WS₂ with PVB and the fabric. The camouflage behavior of the impregnated fabric has been examined firstly in the VIS part of the spectrum. Diffuse reflection, specular gloss and color coordinates were measured for three different shades (black, brown and dark green). Thermal imaging was applied to examine the camouflage abilities of this impregnation in IR part of the spectrum. The obtained results show that PVB/IF-WS₂ impregnation system induced enhacement of the materials camouflage properties, i.e. that IF-WS₂ have a positive effect on spectrophotometric characteristics of the fabric.     

Optimal maintenance policies for serial,multi‐machine systems with non‐instantaneous repairs

We study optimal age‐replacement policies for machines in series with non‐instantaneous repair times by formulating two nonlinear programs: one that minimizes total cost‐rate subject to a steady‐state throughput requirement and another that maximizes steady‐state throughput subject to a cost‐rate budget constraint. Under reasonable assumptions, the single‐machine cost‐optimal and throughput‐optimal solutions are unique and orderable, and the multi‐machine optimal solutions have appealing structure. Furthermore, we establish equivalence between the two formulations and provide an illustrative numerical example. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006     

DESIGNING A VIABLE PREDICTION MARKET TO FORECAST DEFENSE ACQUISITION COST AND SCHEDULE OUTCOMES

This paper is the first to demonstrate a viable prediction market that successfully forecasts defense acquisition cost and schedule outcomes, and to provide insights for defense executive decision‐making. Already used in private industry, prediction markets can also accurately forecast outcomes and their associated risks for government programs. Using virtual money, prediction markets allow traders to ‘bet’ on some future outcome. This market mechanism turns out to be a relatively simple and accurate way to discover, aggregate, and communicate to a defense executive the collective market’s beliefs about the likelihood of an eventual outcome of an acquisition program of interest.     

INTEGRATING NUCLEAR WEAPONS STOCKPILE MANAGEMENT AND NUCLEAR ARMS CONTROL OBJECTIVES TO ENABLE SIGNIFICANT STOCKPILE REDUCTIONS

In his 2009 Prague speech and the 2010 Nuclear Posture Review, President Barack Obama committed the United States to take concrete steps toward nuclear disarmament while maintaining a safe, secure, and effective nuclear deterrent. There is an inherent tension between these two goals that is best addressed through improved integration of nuclear weapons objectives with nuclear arms control objectives. This article reviews historical examples of the interaction between the two sets of objectives, develops a framework for analyzing opportunities for future integration, and suggests specific ideas that could benefit the nuclear weapons enterprise as it undergoes transformation and that could make the future enterprise compatible with a variety of arms control futures.     

From combat to non-combat action

This paper examines the rationale and centrality of private military and security companies (PMSCs) in humanitarian assistance operations in Sudan, asking why PMSCs are involved in humanitarian assistance operations in Sudan and what the principles underlying their activities are. To answer this question, the paper draws attention to the link between humanitarian crises and PMSC interventions. Where there is no meaningful alternative intervention, undergirded by humanitarian concerns that are also profit driven, PMSCs come in to provide the needed services. The protracted and complicated internal armed conflicts in Sudan, which have lasted for over two decades, have produced as many as 4,8 million internally displaced persons (IDPs) – the single largest number in the world. The kind of humanitarian assistance operations provided by PMSCs in Sudan have become critical to the provision of much-needed services which were inadequately provided by governmental authorities at both unilateral and multilateral levels. This paper argues that the humanitarian crises in Sudan created a regime that permits humanitarian assistance operations by both state and non-state actors.     

Icons Off the Mark

In two landmark articles, longtime scholars Kenneth N. Waltz and Thomas C. Schelling have re-emphasized the utility of nuclear deterrence over nuclear nonproliferation (Waltz) and nuclear disarmament (Schelling). While the thrust of the articles is seemingly different, both are rooted in the same intellectual ground: an epistemology that assumes problem-free inferences, drawn from past experiences, are applicable in future scenarios; a foundational rooting in strategic rationality that entangles them in unsolvable contradictions concerning comparable risks of different nuclear constellations, namely deterrence versus proliferation and disarmament; and a bias in framing the empirical record that makes nuclear deterrence more conducive to security than nuclear disarmament. The common normative-practical denominator, then, is to let a nuclear weapon-free world appear both less desirable and less feasible than it might actually be.     

Plunder or Trade?

Plunder and trade are theoretically and historically entwined in complex ways. This paper examines when rational players will choose one or both by employing a model of plunder within an evolutionary game theoretic framework. Evolutionary stable strategy equilibria are derived and the replicator dynamics are examined for simple two-by-two symmetric games. Not only are positive defense allocations necessary for trade, implying that all trade is of a contested nature, but the defense technology must also exhibit sufficient effectiveness relative to the plunder technology. A continuum of possible exchanges is proposed that is based on the effectiveness of enforcing property claims. For high levels of transactions costs, plunder dominates. As transactions costs decline, mutual trade emerges as one possible exchange mechanism. All market exchange entails some cost of enforcement; it is contested. Insufficient enforcement of property claims produces mutual plunder as the dominant exchange mechanism. Some implications are suggested for institutional evolution. C7 K4 N4     

Book reviews

Jurgen Brauer's comment presents what he calls a replication of an earlier study by Higgs and Kilduff (1993) and uses it to criticize the adequacy of the Higgs‐Kilduff model. In several respects, however, Brauer has not actually performed a replication: he uses different data, a different sample period, and arrives at different results. His criticisms rest on his own setup, not that of Higgs and Kilduff. Therefore they have no strict applicability to the latter. Moreover, Brauer's stepwise model has no bearing on the Higgs‐Kilduff model, as it violates that model's specification requirements.     

Patents and Dual-use Technology: An Empirical Study of the World's Largest Defence Companies

Abstract

This paper examines the generation of technological knowledge by leading companies in the defence industry. In particular, we test whether the characteristics of large defence companies are related to both the production of different types of patents (civilian, military and mixed), and the generation of dual-use technologies. To explore these links, we rely on economic data for the top 100 defence companies from the Stockholm International Peace Research Institute database, and patent information from the Worldwide Patent Statistical Database. Our results show that the relationship between the production of civilian patents and the size of the company is positive and significant. However, this relationship does not hold for the production of military patents. Furthermore, the military commercial profile is unrelated to the generation of military patents. Regarding the involvement in dual-use technologies, firms engaged in dual-use are those with higher military sales, a greater number of employees and a larger number of patents (civilian, military and mixed) than those not engaged in dual-use. Furthermore, we found a skill effect (more involvement in dual-use per employee) in European firms compared to US firms. These findings help to identify which firms should be targeted by government policies if increasing dual-use technologies becomes a political objective.