A facility reliability problem: Formulation,properties, and algorithm

Having a robustly designed supply chain network is one of the most effective ways to hedge against network disruptions because contingency plans in the event of a disruption are often significantly limited. In this article, we study the facility reliability problem: how to design a reliable supply chain network in the presence of random facility disruptions with the option of hardening selected facilities. We consider a facility location problem incorporating two types of facilities, one that is unreliable and another that is reliable (which is not subject to disruption, but is more expensive). We formulate this as a mixed integer programming model and develop a Lagrangian Relaxation‐based solution algorithm. We derive structural properties of the problem and show that for some values of the disruption probability, the problem reduces to the classical uncapacitated fixed charge location problem. In addition, we show that the proposed solution algorithm is not only capable of solving large‐scale problems, but is also computationally effective. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

Prospects for Closer GCC Military and Political Cooperation

Abstract

‘[Sovereignty] is possible only within the framework of multinational communities, of common institutions designed to provide common responses to common challenges. Security is no longer attainable in the traditional way. Neither the walled city nor the nation-state can provide protection against attack or threats of physical destruction… Increasingly the politics of nations revolve around the careful management of interdependence.’     

Coercive diplomacy and the Donbas: Explaining Russian strategy in Eastern Ukraine

What were Russia’s objectives in Eastern Ukraine, and why was it seemingly unable to achieve a successful or decisive outcome? In contrast to Russia’s seizure of Crimea, the uprising in Eastern Ukraine was marked by disorganization and chaos. Using proxy and surrogate actors, along with military exercises and the injection of Russian troops, Russia sought to institutionalize a political entity inside Ukraine to influence its domestic politics. In this article, I analyze the mechanisms by which Russia attempted to implement, and later salvage, its strategy. The article contributes to clearer theoretical and practical understanding of limited force in coercive diplomacy, signaling, and a more rigorous treatment of the role and uses of proxy actors.     

Success and Failure in Terrorist Investigations: Research and Lessons from Northern Ireland

Police investigations of terrorist incidents are rarely straightforward. This paper reports the findings of research that looked at low-level paramilitary attacks in Northern Ireland which have taken place during the ceasefire era. Of 500 incidents studied, 28 were followed by the arrest of suspects. The study examines what factors were important for linking later arrests with other features of the incident. These results are discussed in terms of the wider implications for the successful investigation of paramilitary offences and in terms of the specific implications for investigative policing within Northern Ireland.