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61.
Joanna R.Hall Olivia Matthews Timothy N.Volonakis Eric Liggins Karl P.Lymer Roland Baddeley Innes C.Cuthill Nicholas E.Scott-Samuel 《防务技术》2021,17(6):1833-1839
The human visual system is still an important factor in military warfare; military personnel receive training on effective search strategies, and camouflage that can effectively conceal objects and personnel is a key component of a successful integrated survivability strategy. Previous methods of camouflage assessment have, amongst others, used psychophysics to generate distinctiveness metrics. However, the population from which the human observers are drawn is often not well defined, or necessarily appropriate. In this experiment we designed a new platform for testing multiple patterns based on a camouflaged object detection task, and investigate whether trained military observers perform better than civilians. We use a two-alternative forced choice paradigm, with participants searching images of woodland for a replica military helmet displaying Olive Green, Multi Terrain Pattern, US Marine Pattern or, as a conspicuous control, UN Peacekeeper Blue. Our data show that there is no difference in detection performance between the two observer groups but that there are clear differences in the effectiveness of the different helmet colour patterns in a temperate woodland environment. We conclude that when tasks involve very short stimulus presentation times, task-specific training has little effect on the success of target detection and thus this paradigm is particularly suitable for robust estimates of camouflage efficacy. 相似文献
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63.
Charles R. Boehmer 《Defence and Peace Economics》2013,24(3):249-268
This paper extends the joint product model of military alliances to apply to the new strategic doctrine adopted by NATO in the 1990s. In particular, a choice must be made between protecting one's own territory and pooling forces for an alliancewide rapid reaction force. This new model accounts for a host of externalities and their implications for burden sharing, full financing, and allocative efficiency. The Pigouvian taxes that adjust for force thinning and attack deflection are shown to finance optimal border‐protecting forces under a variety of circumstances. Second‐best considerations arise owing to the pure publicness of rapid reaction forces. The ideal toll arrangement does not currently characterize NATO financing, nor is it likely to do so. 相似文献
64.
Bryan R. Early 《The Nonproliferation Review》2013,20(2):259-280
The United Arab Emirates (UAE) has laid out an ambitious plan to become the first Arab country to possess a civilian nuclear energy program. Central to that effort has been the Emirati government's ability to obtain foreign nuclear assistance. This article traces the UAE's strategies for overcoming the obstacles that stood in the way of nuclear suppliers providing assistance. It examines the approach taken by the UAE to assuage the safety and security concerns of nuclear suppliers, how the UAE leveraged its alliances with France and the United States to obtain their cooperation, and its strategies for engaging domestic interest groups in supplier states. The generalizable elements of the UAE's strategies are discussed and used to provide insight into the prospects for other Middle Eastern states' bids to obtain similar assistance. The article concludes with a discussion of the potentially transformative aspects of the strategies employed by the UAE in shaping other countries' pursuit of nuclear energy in the region. 相似文献
65.
James J. Wirtz 《The Nonproliferation Review》2013,20(3-4):333-335
66.
Recent scholarship has largely ignored systematic differences in the existential threats that nuclear-weapon possessors pose to other states. This study theorizes that the capacity to pose existential threats shapes nuclear-armed states’ willingness to use military force against one another. We explore three hypotheses regarding how nuclear-based existential threats can deter conflict or encourage it, including under the conditions proposed by the stability–instability paradox. We rely on a statistical analysis of nuclear-armed dyads from 1950 to 2001 and employ the Nuclear Annihilation Threat (NAT) Index to capture variation in the existential threats nuclear-armed states pose to one another. We find that being able to pose an existential threat to another state emboldens potential initiators to use military force but does not deter attacks. The emboldening effects are particularly strong under the hypothesized conditions of the stability–instability paradox. Our study provides unique contributions to ongoing debates over the political effects of nuclear weapons. 相似文献
67.
The paper examines the impact of civil wars on income per-capita growth at home and in neighbors for four regional groupings of countries: Africa, Asia, Latin America, and a pooled Asian and Latin American sample. Both macroeconomic and civil-war influences on growth differ by region. With the use of a distance measure, we demonstrate that the spatial reach from the negative consequences of a civil war are region and time period specific. Generally, there was less dispersion in Africa than in Asia and Latin America. Moreover, Africa demonstrates a greater ability to recover from the adverse effects of civil wars than the other regions tested. 相似文献
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The criticism of James, Solberg and Wolfson (JSW) (1999) by Oneal and Russett (OR) is not responsive to the methodologica] issues at stake. JSW argued that war is an endogenous feature of the world political and economic system. If its causes are to be measured, it must be as a structural equation in a simultaneous system. Wedded to the idea that “democracies never fight each other,” OR rely on a single equation to justify their view. JSW claim that such an equation may be an ad hoc reduced form with no causal implications unless the equation is explicitly identified as a structural equation. JSW expand the model to explain democracy and conflict as two endogenous variables. JSW do not claim to have discovered the true relationships between these variables by their minimal expansion of the structural relation. They do show that unless these (and other) variables are treated as part of a system, the results are unstable, contradictory, of minimal size and not a reliable guide to public policy. 相似文献