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81.
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   
82.
In order to examine the possibility to improve its camouflage properties standard cotton fabric with camouflage print was impregnated with poly(vinyl butyral), PVB and fullerene-like nanoparticles of tungsten disulfide, PVB/IF-WS2. FTIR analysis excluded any possible chemical interaction of IF-WS2 with PVB and the fabric. The camouflage behavior of the impregnated fabric has been examined firstly in the VIS part of the spectrum. Diffuse reflection, specular gloss and color coordinates were measured for three different shades (black, brown and dark green). Thermal imaging was applied to examine the camouflage abilities of this impregnation in IR part of the spectrum. The obtained results show that PVB/IF-WS2 impregnation system induced enhacement of the materials camouflage properties, i.e. that IF-WS2 have a positive effect on spectrophotometric characteristics of the fabric.  相似文献   
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In nuclear nonproliferation negotiations, many governments pursue multiple objectives, and changes in policy can occur rapidly—and often unexpectedly. For these reasons, understanding nonproliferation requires empathy and imagination rather than just historical fact. This article considers one teaching tool to encourage such insight—simulations—and demonstrates how teaching and scholarship can interact to improve our understanding of the complex decisions and negotiations involved in nuclear nonproliferation. The article consists of five parts: first, it explains the benefits of simulations as both a policy development tool in Washington and as a teaching tool in universities; second, it describes the pedagogical strategy of the Stanford University simulation program; third, it shows how the simulations have identified and highlighted theoretical and substantive insights that are often neglected in scholarly studies of nonproliferation; and fourth, it describes how students are tested to enhance the learning experience from the simulation. Fifth and finally, the article provides concluding observations about how using simulations in the classroom can help scholars develop insights that improve their understanding of real-world nuclear negotiation dynamics and outcomes.  相似文献   
85.
ABSTRACT

An arms race in cyberspace is underway. US and Western government efforts to control this process have largely been limited to deterrence and norm development. This article examines an alternative policy option: arms control. To gauge whether arms-control models offer useful lessons for addressing cyber capabilities, this article compiles a new dataset of predominantly twentieth-century arms-control agreements. It also evaluates two case studies of negotiated agreements that regulate dual-use technologies, the 1928 Geneva Protocol prohibiting chemical- and biological-weapon use and the 1944 Chicago Convention on International Civil Aviation. The analysis underscores the limits of norm development for emerging technologies with both civilian and military applications. It finds lessons for developing verifiable, international cooperation mechanisms for cyberwarfare in the regulatory model of international aviation. Conventionally, arms-control agreements take advantage of transparent tests or estimates of arms. To restrict cyberwarfare activities, experts and policy makers must adapt arms-control models to a difficult-to-measure technology at an advanced stage of development and use. Further investigation of international regulatory schemes for dual-use technology of similar diffusion and development to the internet, such as international civil aviation, is needed.  相似文献   
86.
ABSTRACT

Widespread and often exaggerated generalizations about the global spread weapons of mass destruction (WMDs) have proven to be not only misleading and technologically naïve, but also unhelpful in formulating effective policies to counter their threat. The new book by George Mason University's Sonia Ben Ouagrham-Gormley dispels the popular narrative that governments and terror groups can easily—and inevitably will—develop WMDs, particularly biological weapons, by exploring the complex external and internal conditions that such programs require, as demonstrated by the Cold War-era biological weapon programs of the superpowers. This empirically grounded and realistic assessment of how states try—and often fail—to develop such programs offers a more reliable basis to craft realistic counterproliferation policies that can elicit international support.  相似文献   
87.
With the security situation in Darfur remaining grim, the international community passed United Nations Security Resolution 1769 that authorised a more robust peacekeeping force. This article addresses the security concerns motivating the United Nations-African Union Mission in Darfur (UNAMID), highlights the mandate and implications of the force, and compares the potential command and control issues to the experiences of the Somalia intervention in the 1990s. It closes by analysing the prospects for success of the intervention and offering some limited recommendations on ways to mitigate the risks associated with the peacekeeping effort.  相似文献   
88.
Given Kinsella's (1990, 1991) appeal for analysis to be pursued using sub‐annual level of data, we pursue such an endeavor in this paper. We examime the effect of defence spending on real output, the unemployment rate, price level, and interest rate covering a quarterly time frame 1960:1 to 1988:1 using an unrestricted vector autoregression framework. Our results parallel the findings of Kinsella in that there appears no causal relationship in either direction between defence spending and economic performance.  相似文献   
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