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41.
Karl Sörenson 《Defence Studies》2017,17(2):198-213
The last decade has seen several advances in the study of deterrence. These advances have sparked some strong disagreements regarding interpretation of the models and what their contributions signify. This paper appraises the discussions from a model theoretic perspective. It is argued that when comparing rivalling models three aspects; (i) target, (ii) criteria and (iii) type of purpose should be taken into account in order to make a proper appraisal. Informed by these aspects it is evident that the three deterrence models analysed address different aspects, in different ways and to different ends. From this perspective, the so-called Perfect Deterrence model must be recognised as a clear advancement in the research field. Model comparison will always be context relative and a plurality of models should be viewed favourably. 相似文献
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In late 2011, the Spanish terrorist organization ETA announced the end of armed violence after more than forty years of illegal activity. While the existing literature has already established the negative impact of terrorist actions on international tourism in a particular region, this paper aims to determine whether ETA’s final ceasefire and definitive dissolution had a positive impact on domestic tourism in Basque Country. To that end, a directed gravity model is estimated over a panel data-set of 699 domestic tourist flows between the Spanish regions from 2008 to 2013. Results suggest that the negative impact on visitor flows was localized in the Basque Country. Also, regardless of a permanent ceasefire announced in 2010, only the 2011 ‘definitive cessation of violence’ had an immediate significant impact on the number of visitors to the Basque Country. These results complement the scarce literature on post-conflict tourism analysis and may have implications for regional authorities in affected regions in their efforts to rebuild their destination brands. 相似文献
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We present, analyze, and compare three random search methods for solving stochastic optimization problems with uncountable feasible regions. Our adaptive search with resampling (ASR) approach is a framework for designing provably convergent algorithms that are adaptive and may consequently involve local search. The deterministic and stochastic shrinking ball (DSB and SSB) approaches are also convergent, but they are based on pure random search with the only difference being the estimator of the optimal solution [the DSB method was originally proposed and analyzed by Baumert and Smith]. The three methods use different techniques to reduce the effects of noise in the estimated objective function values. Our ASR method achieves this goal through resampling of already sampled points, whereas the DSB and SSB approaches address it by averaging observations in balls that shrink with time. We present conditions under which the three methods are convergent, both in probability and almost surely, and provide a limited computational study aimed at comparing the methods. Although further investigation is needed, our numerical results suggest that the ASR approach is promising, especially for difficult problems where the probability of identifying good solutions using pure random search is small. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010 相似文献
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The post-civil war agreement phase is vulnerable to credible commitment problems, a lack of government capacity to implement, and/or mutual vulnerability to retribution from violating the agreement. This study’s main contribution is to demonstrate the combined utility of mediation and UN peacekeeping. Mediation builds trust and confidence and works with the parties to design an efficacious agreement conducive to, among other features, tamping down post-agreement violence. Peacekeeping stems violence and facilitates the implementation of the agreement. Agreements that are mediated and followed by UN peacekeeping are expected to be more robust in terms of staving off violence. We report the effects of the mediation–peacekeeping interaction using a method correcting for a common misinterpretation of interaction terms. We test logit and hazard models using a sample of full and partial civil war peace agreements signed between 1975 and 2011. Controlling for agreement design, democracy, and income per capita, the results indicate mediation and its interaction with peacekeeping reduce the probability of renewed/continuing violence and have a positive impact on agreement duration. We also report brief case study evidence from the 1990s peace process in Guatemala. 相似文献
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We propose a dynamic escape route system for emergency evacuation of a naval ship. The system employs signals that adapt to the causative contingency and the crew's physical distribution about the ship. A mixed‐integer nonlinear programming model, with underlying network structure, optimizes the evacuation process. The network's nodes represent compartments, closures (e.g., doors and hatches) and intersections, while arcs represent various types of passageways. The objective function integrates two potentially conflicting factors: average evacuation time and the watertight and airtight integrity of the ship after evacuation. A heuristic solves the model approximately using a sequence of mixed‐integer linear approximating problems. Using data for a Spanish frigate, with standard static routes specified by the ship's designers, computational tests show that the dynamic system can reduce average evacuation times, nearly 23%, and can improve a combined measure of ship integrity by up to 50%. In addition, plausible design changes to the frigate yield further, substantial improvements. Published 2008 Wiley Periodicals, Inc. Naval Research Logistics 2008 相似文献
47.
The Ethnic Russian as an Enemy of Islam: Frame Analysis of the Kavkaz Center News Agency (2001–2004)
Adrián Tarín Sanz 《Civil Wars》2017,19(4):495-516
AbstractTypically, when analysing contemporary Russian–Chechen conflicts, the relegation of the nationalist struggle to a secondary role by the religious battle waged by the North Caucasus insurgency is pinpointed as one of the fundamental differences between the First and Second War in Chechnya. This article discusses how it was reflected in one of the most important media of the Chechen Islamist insurgency: the Kavkaz Center. To this end, 2859 English language news items posted on the website during 2001–04 were reviewed using media frame analysis. 相似文献
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Philip Adémọ́lá Ọláyọkù 《African Security Review》2017,26(4):378-398
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. 相似文献
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Based on the first-person account of coauthor Pierre Billaud, a prominent French participant, this article describes for the first time in such detail the history of the development of the French hydrogen bomb in the 1960s and the organization of military nuclear research in France. The authors illustrate the extent to which French defense and governmental authorities did not support research on thermonuclear weapons until 1966. Billaud, a project insider, relates the historical episodes that led to France's successful 1968 thermonuclear test, including the names of the individuals involved and how a timely tip from a foreign source hastened the success of the first H-bomb test. 相似文献
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