Block replacement policies for a two‐component system with failure dependence

Block replacement and modified block replacement policies for two‐component systems with failure dependence and economic dependence are considered in this paper. Opportunistic maintenance policies are also considered. Where tractable, long‐run costs per unit time are calculated using renewal theory based arguments; otherwise simulation studies are carried out. The management implications for the adoption of the various policies are discussed. The usefulness of the results in the paper is illustrated through application to a particular two‐component system. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003     

Between vigilantism and ethnocultural preservation: An investigation into the legitimacy of the non-state policing activities of the Ombatse group among the Eggon people of Nassarawa State,Nigeria

Postmodern contradictions in postcolonial Nigeria have led to the fetishisation of alternative local security measures often labelled as vigilante activities. The profiling of these groups as ethnic militia often undermines their essential bid to provide security while delimiting security needs to the physical. The fallouts of such profiling are frictions between federal security agents and ethnic-based security groups, often resulting in violence, as exemplified by the 7 May 2013 incident between the Nigerian federal security agents and the Ombatse. This study focuses on the emergence and activities of the Ombatse as an alternative security apparatus of the Eggon. It presents three years of field research which entailed the use of ethnography, key informant interviews and observation. The findings reveal that the Ombatse emerged to assert historical legitimacy for both the physical and spiritual securitisation of the Eggon through a return to the ancestral ways of social engineering. The study considers the security challenges in Nigeria, and also situates the Eggon historical context within political, religious, sociocultural and economic intersections of securitisation. It concludes that the Ombatse situates its legitimacy within the Eggon past and retains its relevance through the holistic focus of providing both physical and spiritual security.     

Self-Interest versus the Common Cause: Austria,Prussia and Russia against Napoleon

This essay re-examines coalition warfare during the Napoleonic era by looking at the three eastern European powers – Austria, Prussia and Russia – how they interacted over time with France as well as each other, and how they managed French preponderance on the Continent. Before 1812, coalition warfare was dominated by eighteenth-century military and diplomatic attitudes: overall foreign political goals were ill-defined and were characterised by deep mistrust. The result was that the eastern powers pursued their own interests with little regard to coalition cohesion. If the coalition held together in 1813 and 1814, on the other hand, it was largely because individual powers' self-interest coincided with the overall objectives of the coalition – an increased determination to defeat Napoleon – along with a never before seen numerical superiority in allied troops. In this, Austria and especially Chancellor Metternich's role in juggling conflicting interests between the allies so that they could present, for the first time, a united front against France was fundamental.     

Nonlinear programming the choice of direction by gradient projection

Rosen's method of Gradient Projection chooses a search direction which is not necessarily the direction of steepest ascent. However, the projection of the gradient onto a “suitably chosen subspace” does yield the direction of steepest ascent. The suitable choice is easily recognized as a result of some theorems relating gradient projection to steepest ascent. These results lead to a modification of Rosen's method. The modification improves the choice of search direction and usually yields the steepest ascent direction without solving a quadratic programming problem.     

Intelligence and military doctrine: paradox or oxymoron?

This article examines the evolution of the current British military joint intelligence doctrine. We argue that military intelligence doctrine is dogged by an intrinsic tension between the ethos and expectations of military doctrine and those of the professional practice of intelligence. We further argue not only that prior iterations of UK joint intelligence doctrine failed to effectively deal with this intelligence doctrine dilemma, but also that measures in the current doctrine to address this problem directly created their own problems. Moreover, as a result, otherwise sound innovations in the current UK intelligence doctrine have proven unsuitable to wider diffusion in more recent intelligence doctrine such as the new NATO intelligence doctrine which, otherwise, draws extensively on its British precursor.