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281.
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Jill D. Humphreys Glenn Porter Michael Bell 《Forensic Science International Supplement Series》2008,178(1):46-53
Research into fingermark enhancement techniques has traditionally used visual comparisons and qualitative methods to assess their effectiveness based on the quality of the developed fingermark. However, with increasing research into the optimisation of these techniques the need for a quantitative evaluative method has arisen. Parameters for acceptable fingerprint quality are not well defined and generally encompass clear, sharp edges and high levels of contrast between the fingermark ridges and background material. Using these current parameters, a conclusive measurement of fingerprint quality and thus the effectiveness of development techniques cannot be achieved.This study presents a model through which an aspect of fingerprint quality can be objectively and impartially measured based on a relative contrast index, constructed through measuring the reflective intensity of the fingermark ridges against the background material. Using a fibre-optic spectrophotometer attached to a microscope with axial illumination, the intensity counts of the ridge detail and background material were measured and a logarithmic contrast index constructed. The microscope and spectrophotometer parameters were experimentally tested using a standard colour resolution chart with known reflective properties. The protocol was successfully applied to four sample groups: black inked fingerprints on white paper; latent fingermarks on white paper developed separately with ninhydrin and physical developer; and fingermarks in blood deposited on white tiles and enhanced with amido black. The contrast indices obtained quantitatively reflect the level of contrast and provide an indication of fingerprint quality through a numerical representation rather than previous qualitative methods. It has been suggested that the proposed method of fingerprint quantification may be viable for application in the forensic research arena as it allows the definitive measurement of contrast to aid the evaluation of fingermark detection and enhancement techniques. 相似文献
283.
Thomas Ambrosio 《欧亚研究》2008,60(8):1321-1344
This article examines how the Shanghai Cooperation Organization (SCO) seeks to undermine democratisation in Central Asia. Prior studies of the interplay between international organisations and democracy have tended to examine only one half of this relationship: whether, how, and under what circumstances do international organisations promote democracy? However, the opposite has been largely ignored: how do international organisations sustain autocracy? Authoritarian governments are increasingly adopting policies aimed at preserving their political power and the SCO represents an additional strategy in this regard: utilising multilateral cooperation to defend themselves against regional or global democratic trends. As such, the ‘Shanghai Spirit’ may be a sign of things to come as autocratic leaders become more bold in their rejection of democratic norms. 相似文献
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Brownlee Thomas 《Canadian public administration. Administration publique du Canada》1986,29(3):425-444
Abstract: This paper addresses a number of questions regarding the role of Teleglobe Canada in a rapidly changing regulatory environment. The historical reasons for Teleglobe's exclusion from CHTC regulation are looked at, together with the likelihood of its continued special status vis-à-vis the other carriers. Taking into consideration recent trends in international telecommunications policy, the impact of Teleglobe's denationalization on the domestic industry is also considered. Finally, recommendations are made aimed at resolving some of the issues associated with privatization. A greater role is envisaged for both the federal Communications minister and the CHTC with respect to Teleglobe. Special emphasis is placed on the need to establish a comprehensive national telecommunications policy involving greater precision with regard to overriding priorities and considerable flexibility, especially in view of the highly innovative character of the sector. 相似文献
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Frederick W. Bell 《政策研究评论》1986,6(2):374-381
Coastal beaches are a source of considerable recreational activity, but are also eroding at a rapid rate. Since beach resources are common property, there is no organized market to determine economic benefits from recreational use. Through a willingness to pay equation for beach use, this article demonstrates how proposed beach renourishment policy can be evaluated within a benefit-cost analysis framework. Benefits are estimated as the incremental willingness to pay per day for a larger beach width which is translated into annualized benefits. Annualize cost of achieving maximum benefits are calculated from a cost function. Given the existing cost of beach renourishment, it was found that all beaches in Florida that are overcrowded (i.e., had less than 112 square feet per person/day) could be renourished at a benefit-cost ratio greater than unity. In Florida, beach renourishment policy for overcrowded beaches yields more economic benefits than costs. However, this technique does not lend itself to policy analyses of uncrowded beaches that are undergoing considerable erosion. 相似文献