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In the statistical interpretation of forensic glass evidence it is standard practice to make the assumption of homogeneity of the refractive index (RI) of the source glass, or of localized homogeneity. However, the work of Locke and Hayes showed that, for toughened windscreen glass, this assumption might not be true. This work is well cited, but there appears to have been little follow-on published research. Furthermore, the toughening process is something known to affect the refractive index, and is a process that float glass does not undergo. Float glass is a major component of casework in New Zealand and for that reason it would be interesting to know whether the findings of Locke and Hayes apply when dealing with float glass. In this paper we describe an experiment similar to that of Locke and Hayes, systematically examining the variation of RI in a pane of float window glass. It was found that, although there were no systematic differences in refractive index, there were observable differences across the pane.  相似文献   
86.
This article argues that, despite environmental issues climbing higher on the political agenda and considerable recent policy activity, rhetoric is not matched by reality in our efforts to manage the Australian environment. We integrate the imperatives emerging from the policy and sustainability literatures and from actual policy, with detailed work on wildlife conservation in Victoria's Central Highlands. Our analysis demonstrates that, rather than undertaking the more intensive policy and 'adaptive management' that is needed, governments are often doing less and may actually be 'taking their hands of their wheel'. Some public policy and administration implications of the emerging policy field of sustainability are illustrated.  相似文献   
87.
Ministerial reshuffles are complex exercises requiring careful handling. A frequent occurrence in British government, their significance is usually seen in political terms. Prime Ministers attach great importance to maximizing the political advantages to be gained from them. This factor is the chief determinant of their logistics, the principal characteristics of which are secrecy in advance and the speed with which ministerial changes are executed. These features - as much as the frequency of ministerial changes per se - may disrupt the policy process and have serious implications for minister-civil servant power relations. Such problems could be alleviated by giving ministers advance notice of changes of post. The institution of a process of ministerial handovers would strengthen the position of incoming ministers by making them less dependent on their officials, upon whom they rely heavily for initial briefing at present.  相似文献   
88.
Misidentification syndromes have been studied from a variety of perspectives, including phenomenological, biological, and nosological approaches. More recently, misidentification syndromes have been studied from a psychiatric-legal perspective, especially with regards to the problem of dangerousness. Capgras syndrome and other syndromes of misidentification can lead to hostile mood and subsequent physical violence. Little attention has so far been devoted to children as the objects of the psychotic person's misidentification delusion(s). We provide a review of cases from the anglophonic literature that have children as the misidentified objects, add three new cases, and then discuss the relationship between misidentification and potential harm to these children.  相似文献   
89.
In many countries it is left to the discretion of the court to accept or reject conclusions based on sampling procedures as applied to the total drug exhibit. As an alternative to this subjective approach, a statistical basis is presented using binomial and hypergeometric distributions to determine a lower limit for the proportion of units in a population which contains a drug, at a given confidence level. A method for calculating the total weight of a drug present in a population within a given confidence interval is also presented. In the event of no failures (all units sampled contain a drug), a sample size of six or seven units is generally sufficient to state that a proportion of at least 0.70 of the population contains a drug at a confidence level of at least 90%. When failures do occur in the sample, point estimation is used as the basis for selecting the appropriate sample size.  相似文献   
90.
A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.  相似文献   
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