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71.
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
72.
Person-borne improvised explosive devices (PBIEDs) are often used in terrorist attacks in Western countries. This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard. An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour, including positions, velocity, and trajectory angles. These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis. In the probabilistic analyses a probability of fatality or serious injury was computed. Based on the results presented, many practical conclusions can be drawn, for instance, regarding safe evacuation distances if a person were exposed to a suspected PBIED. 相似文献
73.
Cyber operations are relatively a new phenomenon of the last two decades.During that period,they have increased in number,complexity,and agility,while their design and development have been processes well kept under secrecy.As a consequence,limited data(sets)regarding these incidents are available.Although various academic and practitioner public communities addressed some of the key points and dilemmas that surround cyber operations(such as attack,target identification and selection,and collateral damage),still methodologies and models are needed in order to plan,execute,and assess them in a responsibly and legally compliant way.Based on these facts,it is the aim of this article to propose a model that i))estimates and classifies the effects of cyber operations,and ii)assesses proportionality in order to support targeting decisions in cyber operations.In order to do that,a multi-layered fuzzy model was designed and implemented by analysing real and virtual realistic cyber operations combined with interviews and focus groups with technical-military experts.The proposed model was evaluated on two cyber operations use cases in a focus group with four technical-military experts.Both the design and the results of the evaluation are revealed in this article. 相似文献
74.
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
75.
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
76.
Tlohang W. Letsie 《African Security Review》2013,22(3-4):291-307
ABSTRACTThe Kingdom of Lesotho spends around five per cent of its annual budget – some 700 million Maloti ($US52.6 million) in 2017 – on the Lesotho Defence Force (LDF). Lesotho’s geographical position means that the LDF has no meaningful role regarding its primary function of defending the country from external aggression and it hardly engages in its secondary functions. In addition, the LDF has a long history of interference with democratic processes and engaging in human rights abuse. The financial resources currently allocated to the LDF could do far more for security, widely defined, if they were allocated to a number of other government expenditure categories. 相似文献
77.
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
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