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Anthony A. Braga 《Journal of Quantitative Criminology》2003,19(1):33-54
Boston, like many other major cities, experienced a sudden increase in youth homicides during the late 1980s and early 1990s. Research evidence suggests that the recent epidemic of urban youth violence was intensely concentrated among criminally active young black males residing in disadvantaged urban neighborhoods rather than all young black males residing in disadvantaged black neighborhoods. Other researchers, however, suggest that there was a diffusion of guns and gun violence from youth involved in street crack markets to youth outside the drug trade who armed themselves primarily for self-protection against the armed criminally active youth. In this paper, criminal history data are analyzed to determine whether the criminal profile of Boston arrested youth gun offenders changed over time and micro-level data on youth gun assault incidents in Boston are examined to unravel whether there were noteworthy changes in the nature of these violent events over time. The results of these analyses suggest that the youth violence epidemic in Boston was highly concentrated among serious youth gun offenders rather than a diffusion of guns away from the street drug trade, gangs, and criminally active youth. 相似文献
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Anthony Tanney 《The Modern law review》1993,56(4):575-580
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The microscopical examination of original surfaces on casework sized glass particles using an interference objective and the interpretation of their interferograms is discussed. To reduce subjectivity, a numerical criterion was devised to assess the curvature of glass particles and this was then applied to a survey of window, container, tableware and vehicle glasses. Objects with curved surfaces produced particles that were distinctly curved while those from surfaces of both modern and old windows were clearly identifiable as flat. Apparently flat surfaces from tableware and containers almost always yielded specimens that were detectably curved. In addition, there was no evidence that a fracture surface would be confused with an original surface from a plain flat glass.In a ‘blind’ trial to assess the interferometric routines, three examiners correctly identified flat and curved surfaces on 15 particles derived from a selection of glass objects. 相似文献
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Robert Anthony 《政策研究评论》1982,1(4):705-715
The requirements for dependable management of complex hazardous technologies include multiple barriers against serious failure, clear accountability for errors, and credibility for the decision-making process. Unfortunately, these requirements are in direct conflict. These conflicts can undermine the public's assurance that their health and safety concerns are being properly addressed. These conflicts can be reduced by the adoption of policies that enhance information exchange and evaluation, thereby, complementing the current policies based on physical safe guards and adversarial processes. 相似文献