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Ryan Spotts M.S. L. Scott Chumbley Ph.D. Laura Ekstrand M.S. Song Zhang Ph.D. James Kreiser B.S. 《Journal of forensic sciences》2015,60(4):878-884
A blind study to determine whether virtual toolmarks created using a computer could be used to identify and characterize angle of incidence of physical toolmarks was conducted. Six sequentially manufactured screwdriver tips and one random screwdriver were used to create toolmarks at various angles. An apparatus controlled tool angle. Resultant toolmarks were randomly coded and sent to the researchers, who scanned both tips and toolmarks using an optical profilometer to obtain 3D topography data. Developed software was used to create virtual marks based on the tool topography data. Virtual marks generated at angles from 30 to 85° (5° increments) were compared to physical toolmarks using a statistical algorithm. Twenty of twenty toolmarks were correctly identified by the algorithm. On average, the algorithm misidentified the correct angle of incidence by ?6.12°. This study presents the results, their significance, and offers reasons for the average angular misidentification. 相似文献
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Few political institutions are as central to theories of lawmaking as the executive veto. Despite its importance, institutional continuity at the national level has precluded identification of empirical effects of the veto on legislative behavior. We address this limitation and present evidence from the states demonstrating how the veto affects the formation of legislative coalitions and, indirectly, executive influence over policymaking. We find consistent evidence that the presence and strength of gubernatorial veto powers affect the lawmaking behavior of state legislatures. Our analysis shows how institutional provisions condition executives' ability to affect policy outcomes in separation‐of‐powers systems. 相似文献
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Increasing public awareness of cyberbullying, coupled with several highly publicized youth suicides linked to electronic bullying, have led lawmakers and politicians to consider new criminal legislation specifically related to cyberbullying. However, little is known about how the police currently respond to cyberbullying, and it is not clear whether new laws are necessary. In this article, the authors draw upon in-depth interviews with Canadian street patrol officers and school resource officers to explore police perspectives on policing cyberbullying. In contrast to the reactive hard-line approach proposed in much legislation and public discussion, police officers prefer to take a preventative approach by educating youth and raising awareness about the dangers of digital communications. Although there are instances when criminal charges must be laid, these incidents transcend “bullying,” a term that has little legal meaning for police officers. 相似文献