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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   
33.
ABSTRACT

Although the existing international-relations scholarship argues that technological assistance in the nuclear domain increases the probability of nuclear proliferation, the historical account indicates otherwise. Congressional legislation for nonproliferation, economic sanctions, and poor state capacity—specifically, inept managerial capabilities of the recipient state—explain merely part of the puzzle, but overlook the role of positive inducements offered to impede nuclear proliferation. Historical evidence shows that the United States often provided technological assistance with the deliberate intent to inhibit proliferation. In other words, Washington employed its technological leverage to attain nonproliferation goals. American technological preponderance since the end of World War II made such an approach feasible. This study examines key Cold War cases—Israel/Egypt, India, and West Germany—where the United States offered technological assistance with the deliberate intent to stall nuclear proliferation, thereby underscoring the role of assistance for inhibitive ends.  相似文献   
34.

After a decade of successful recruiting, the US military began experiencing recruiting difficulties in the 1990s. Cyclical factors as well as trend factors may have played a role. This paper uses monthly data by state over the period 1989-1997 to estimate models of enlistment and evaluate the various explanations for the recruiting slowdown. Estimates of the impact of economic variables - relative military pay and unemployment - and recruiting resource variables - recruiters and advertising - are similar to those in previous studies. Two trend factors, rising college attendance and declining adult veteran population (influencers), are found to be important factors explaining the decline in enlistment.  相似文献   
35.
It is intrinsic to the nature of military competition that the unit acquisition costs of defence systems rise generation by generation. Traditional “bottom‐up” methods of cost‐estimating cannot meet the increasing demands for extensive studies of many options before commencing design and, while “top‐down” estimating techniques are an improvement, in particular by reducing the time required for preparing estimates, they also are inadequate to meet current requirements. A new method has been devised, therefore, further developing “top‐down” methods using Bayesian techniques to make best use of the available information, whether certain or uncertain, and its accuracy established by example.  相似文献   
36.

This paper analyzes a set of observations by the Congressional Budget Office (CBO) on individual weapons systems regarding whether large amounts of excess capacity exist and whether short run average cost (SRAC) appears to be severely decreasing. It is shown that the amount of excess capacity and steepness of SRAC are essentially independent of output rate. It is then argued that this suggests that production is occurring in inefficiently large plants—i.e.—off the long run cost curve.  相似文献   
37.
South Africa's military has, since the First World War, been an oft-used and effective tool in the conduct of South African foreign policy, but this role has not always translated into power for Defence Department principals in its formulation. South African Defence Ministers for most of the country's history have played a minor role in the making of foreign policy; despite a change in this dynamic between approximately 1975–1990, the post-apartheid era has once again seen a diminishment of Defence's power in this arena. This article examines why Defence Ministers have generally been such weak players, with an eye toward disaggregating whether this was a product of interpersonal relationships with Cabinet and – most importantly – the Head of State, or whether this influence (or lack thereof) was more a function of South Africa's international standing. While determining who has influence on this process is difficult given the primacy of the national leader in making foreign policy and a lack of insider accounts by participants in the process, this article relies upon several interviews with participants and knowledgeable observers that help illuminate the process and Defence's role in it.  相似文献   
38.
Recently in this journal Hooper and Butler (1996) drew attention to the scale of job loss associated with restructuring in the defence sector in the aftermath of the Cold War. They noted that there is comparatively little knowledge of the experiences of workers following the closure of defence plants. This research communication attempts to shed further light on this issue by reporting the results of a survey of the experiences of former Swan Hunter shipyard workers who were made redundant after the firm went into receivership. The results confirm the complex but generally negative effect of redundancy on the workers involved.  相似文献   
39.

Thomas Schelling argues that armed adversaries face an inherent propensity toward peace or war embodied in their weaponry, geography and military organizations. Inherent propensity is the idea that there are characteristics embodied in the weapons that push adversaries toward peace or war, independent of the goals of the decision‐makers, the political disagreement between adversaries, and misperceptions about mutual resolve and hostility. We theoretically illustrate inherent propensity in conventional and nuclear arms settings using Lanchester and Intriligator war models. Our work extends the Intriligator‐Brito model, identifies when the competing Richardson and Intriligator‐Brito views of the relationship between arms races and war are correct, illustrates the stabilizing/destabilizing effects of alliances, and highlights the importance of arms quality control in the US‐USSR relationship.  相似文献   
40.
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