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331.
Information technology (IT) infrastructure relies on a globalized supply chain that is vulnerable to numerous risks from adversarial attacks. It is important to protect IT infrastructure from these dynamic, persistent risks by delaying adversarial exploits. In this paper, we propose max‐min interdiction models for critical infrastructure protection that prioritizes cost‐effective security mitigations to maximally delay adversarial attacks. We consider attacks originating from multiple adversaries, each of which aims to find a “critical path” through the attack surface to complete the corresponding attack as soon as possible. Decision‐makers can deploy mitigations to delay attack exploits, however, mitigation effectiveness is sometimes uncertain. We propose a stochastic model variant to address this uncertainty by incorporating random delay times. The proposed models can be reformulated as a nested max‐max problem using dualization. We propose a Lagrangian heuristic approach that decomposes the max‐max problem into a number of smaller subproblems, and updates upper and lower bounds to the original problem via subgradient optimization. We evaluate the perfect information solution value as an alternative method for updating the upper bound. Computational results demonstrate that the Lagrangian heuristic identifies near‐optimal solutions efficiently, which outperforms a general purpose mixed‐integer programming solver on medium and large instances. 相似文献
332.
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. 相似文献
333.
Colin D. Robinson 《Defense & Security Analysis》2019,35(2):211-221
To engage properly with the Somali National Army, to understand it in the hope of improving stability and the lives of over 12 million Somalis, good basic information on its composition and characteristics is necessary. Authoritative accounts on the subject have been scarce for over 25 years. This account seeks to detail the army’s dispositions across southern Somalia, and, more importantly, the brigades’ clan compositions and linkages. Clan ties supersede loyalties to the central government. The army as it stands is a collection of former militias which suffer from ill-discipline and commit crime along with greater atrocities. Estimates of numbers are unreliable, but there might be 13,000 or more fighters in six brigades in the Mogadishu area and five beyond. 相似文献
334.
335.
The damaging economic effects of the debt crises on Africa in the late 1980s encouraged considerable research on the determinants of external debt in developing economies. Although sub-Saharan Africa's (SSA) debt was cut by two-thirds by 2008, through two debt relief programmes, debt in the region has since been rising at an increasingly rapid pace. This study provides an empirical analysis of the determinants of external debt in SSA over the period 1960–2016, using dynamic panel methods. It also considers two potentially important factors that have received relatively little attention. One is military spending, rarely considered, despite a number of well-publicised scandals over the procurement of unnecessary and expensive high-tech weapons systems. A second, is the possibility that the countries studied have been involved in conflict. The empirical results point to a positive impact of military spending on external debt, but with some evidence of heterogeneity across the countries. Furthermore, findings indicate that the positive effect of military expenditure on debt becomes more marked in countries that have been affected by conflict. These results imply that policies to improve security and reduce military spending could be beneficial in reducing external debt and, potentially, improving economic performance in the region. 相似文献
336.
Patrick A. Mello 《Contemporary Security Policy》2019,40(1):38-55
Recent scholarship in security studies has started to explore the causes and consequences of various forms of national restrictions in multinational military operations (MMOs). This article makes a conceptual contribution to this literature by developing a theoretical framework of national restrictions in MMOs that distinguishes between structural, procedural, and operational restrictions. I argue that these types of restrictions are governed by different causal mechanisms. Structural restrictions are relatively stable over time and effect deployment decisions irrespective of other factors. Procedural restrictions, on the other hand, can constitute veto points against deployment only in combination with distinct political preferences. Finally, operational restrictions directly affect the rules of engagement of troop contributing countries. The article illustrates the three types of restrictions and their interaction with empirical examples from a range of countries and sketches their impact on MMO deployment decisions and mandates. 相似文献
337.
Michael H. Clemmesen 《Defense & Security Analysis》2019,35(1):96-97
The article outlines the essential role of free play elements in various types of exercises for the development of in-depth and practical military professionalism. It thereafter argues why such use of free play contradicts the military science founded Russian Way of War. 相似文献
338.
David H. Tomback 《Arms and Armour》2019,16(1):56-74
The sword which is the subject of this article and which will be referred to as the Capel sword, is a fine example of what has become known as an Irish basket-hilt. Whilst there are other examples in existence, what makes this sword unique and particularly important is the fact that it is known to have been owned by two important Royalist military leaders, Lord Arthur Capel and Sir John Owen. These two extraordinary men came from different backgrounds but their fate was linked through circumstances beyond their control. The story this sword tells is one of comradeship, loyalty, total belief in a cause, betrayal and ultimate sacrifice. 相似文献
339.
A company wishes to estimate or predict its financial exposure in a reporting period of length T (typically one quarter) because of warranty claims. We propose a fairly general random measure model which allows computation of the Laplace transform of the total claim made against the company in the reporting interval due to warranty claims. When specialized to a Poisson process of both sales and warranty claims, statistical estimation of relevant quantities is possible. The methodology is illustrated by analyzing automobile sales and warranty claims data from a large car manufacturer for a single car model and model year. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
340.