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171.
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There have been growing claims in media circles and law-enforcement settings that street gangs and criminal groups are turning to Internet-based social networking sites for various reasons ranging from the showcasing of their images and exploits to the suspected recruitment of members. The present study investigates whether such a trend is, in fact, in place. The presence of street gangs on these Internet sites is referred to as cyberbanging. While there is some anecdotal evidence suggesting that gangs are turning to social networking sites, there is little available research on exactly how street gangs and criminal groups use the Internet. Our main argument is that gang culture is in many ways an individualized phenomenon and this feature ties in directly with recent assessments of the Internet as a setting that is governed by a process of networked individualism. This theoretical link between the individualized gang setting and the presence of gang members on social networking sites helps us understand why recruitment is improbable even in a context where people are openly diffusing their image and exploits to a growing number of Internet users. The empirical segment of this research adds to this general outlook. Based on a keyword search of over 50 street gang names, the three main social networking sites (Twitter, Facebook, and MySpace) were monitored for street gang presence. Results illustrate that gang presence on social networking sites is linked primarily to promoting a general gang or street culture through individual displays. In regard to the visitors to such sites, there is no evidence that they are being tricked or manipulated in any way. They are, however, showing their curiosity in regard to such groups and, for those who share their comments and opinions, signs of support are evident. Thus, whereas criminal gangs are not proactively using the Internet to convert anyone into being gang members, social networking sites are creating a new venue for people who share or are sensitive to the values underlying street gang lifestyle to come together. These sites essentially create a new convergence setting for gang members to interact with a wider number of people who would probably never have been exposed to their lifestyles and exploits through physical interactions. The study's conclusion extends these findings toward further research in this area, as well as outlining the more relevant implications for law-enforcement monitoring of this growing phenomenon.  相似文献   
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Book reviews     
The Political Economy of Military Spending in the United States, Alex Mintz (ed), London and New York: Routledge, 1992, pp x, 334; ISBN 0–415–07595–5

Penser La Guerre, Penser L'Economie, Christian Schmidt, (Paris: Odile Jacob, 1991), 350p.

Military Production and Innovation in Spain, Jordi Molas‐Gallart, Chur (CH): Harwood Academic Publishers, 1992, pp. vii, 212; ISBN 3–7186–5280–3  相似文献   
175.
This paper describes a stochastic simulation of one of the key naval operations in World War II, and shows how the result of that operation might have differed considerably from the historical outcome. The simulation demonstrates that it is never possible to predict with confidence the results of military operations involving a few high‐value units.  相似文献   
176.
Developments within the UK in the Ministry of Defence’s policy on defence equipment acquisition demand changes in the scale and allocation of the Ministry’s budget for defence research. To facilitate the national debate on those changes, this paper reviews the key questions about UK defence research which the Ministry must resolve in order to implement its new Defence Technology Strategy.  相似文献   
177.
Mali has been a battleground for more than a year now. While the armed conflict came in the aftermath of the Libyan crisis that left the regional security environment depleted, it also served as a catalyst for the collapse of state authority in Mali. This created conditions conducive for the proliferation of, and attacks by, radical religious armed groups in the northern regions of the country, including the Tuareg armed movement: the National Movement for the Liberation of Azawad (MNLA). But, far from being a new phenomenon, the Tuareg-led armed insurrection in the northern regions is as old as the post-colonial Malian state, and continues to pose tremendous challenges in West Africa and the Sahel region for both regional and extra-regional actors. The recent crisis in the Sahel region is seen as one of the most serious since the end of the Cold War, with anticipated dire long-term impacts on the security of the region and beyond. While attention is predominantly focused on defeating the jihadist groups that have threatened the survival of the Malian state, one must not lose sight of the fact that the ‘Tuareg Factor’, as represented by the rebellion launched by MNLA, remains critical both in terms of appreciating the deterioration of the situation and attempting to frame long-lasting solutions. The paper argues that the Tuareg's persistent recourse to rebellion against Bamako needs to be understood within a historical trajectory that takes into consideration three key parameters: firstly, the post-colonial state in Mali and its African leadership's relations with the descendants of the Tuareg communities; secondly, the amalgamation created by the so-called war on terror; and, finally, the contradictions of the democratisation process of the 1990s.11 This article is based on field research carried out between 2008 and 2013 on the ‘Resurgence of Tuareg-led Rebellions’.  相似文献   
178.
When it was concluded more than a quarter century ago, the Intermediate-Range Nuclear Forces (INF) Treaty between the United States and the Soviet Union was hailed as a disarmament watershed, eliminating entire classes of nuclear missiles from the arsenals of the arms-racing Cold War superpowers. Over the intervening decades, there have been repeated calls to convert this legacy treaty into a new international norm against nuclear and missile proliferation by broadening it into a global prohibition on ground-launched ballistic and cruise missiles with ranges between 500 and 5,500 kilometers. Indeed, variations on this proposal have been knocking around for so long and with so little success that the entire concept has come to be dismissed by many knowledgeable insiders as something of a farce. Looking beyond its inauspicious pedigree, however, this viewpoint suggests that the time is opportune for Washington to give the idea a fresh look. Drawing on a detailed review of the history of “Global INF” and an analysis of the contemporary context, the author recommends that the Obama administration consider a simple declaratory approach that promises modest initial benefits, avoids previous and foreseeable pitfalls, and plausibly lays a solid foundation for achieving significant long-term progress.  相似文献   
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We study a stochastic interdiction model of Morton et al. IIE Transactions, 39 (2007):3–14 that locates radiation sensors at border crossings to detect and prevent the smuggling of nuclear material. In this model, an interdictor places sensors at customs checkpoints to minimize a potential smuggler's maximum probability of crossing a border undetected. We focus on a model variant in which the interdictor has different, and likely more accurate, perceptions of the system's parameters than the smuggler does. We introduce a model that is tighter and uses fewer constraints than that of Morton et al. We also develop a class of valid inequalities along with a corresponding separation procedure that can be used within a cutting‐plane approach to reduce computational effort. Computational results demonstrate the effectiveness of our approach.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 91–100, 2014  相似文献   
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