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近年来网络犯罪数量呈快速上升的势头,但是却缺乏一种有效的取证方法来处理这些案件.调查人员通常依靠调查大量繁琐的源代码来了解犯罪模型及提取证据,但这种方式需要很多的人力与时间,并可能导致人为错误.为了克服调查人员可能出现的这些潜在错误,我们在本文中提出了一种半自动的方法来解决这些问题.该方法集成了用户视图(基于取证调查人员的高级别研究)和系统视图(基于对源代码的自动分析),来帮助调查人员精确调查的范围.本文应用此方法分析了一个真实案件,证明了方法的可行性,同时帮助调查人员高效地确定了调查范围和犯罪模型.可见这种半自动方法可以对大量有多个来源的电子证据进行有效分析,提高了网络犯罪案件取证的效率和可靠性.  相似文献   
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The relationship between law and coercion has been, and still is, a central topic in legal philosophy. Despite this, discussion about it is immersed in confusion. Some philosophers have noticed this, but hardly any work has been done to attempt to solve or even identify the confusions. This paper aims to fill this gap. Here I propose distinctions and qualifications that help us clarify the relationship between law and coercion and avoid confusion. Building on the clarificatory work, I then argue that despite there being several distinct philosophical discussions about the relationship between law and coercion, one of them should be prioritised.  相似文献   
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The comparative study of subnational units is on the rise. Multilevel regression and poststratification (MrP) has become the standard method for estimating subnational public opinion. Unfortunately, MrP comes with stringent data demands. As a consequence, scholars cannot apply MrP in countries without detailed census data, and when such data are available, the modeling is restricted to a few variables. This article introduces multilevel regression with synthetic poststratification (MrsP), which relaxes the data requirement of MrP to marginal distributions, substantially increases the prediction precision of the method, and extends its use to countries without census data. The findings of Monte Carlo, U.S., and Swiss analyses show that, using the same predictors, MrsP usually performs in standard applications as well as the currently used standard approach, and it is superior when additional predictors are modeled. The better performance and the more straightforward implementation promise that MrsP will further stimulate subnational research.  相似文献   
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Over the past decades, consume of slimming agents considerably increased in several countries, including Brazil, due to weight-loss and stimulant properties. Since these drugs are controlled to prevent illicit and indiscriminate use, there is a parallel illegal market that uses the Internet and irregular pharmacies in order to distribute these formulations. Slimming agents produced by these illegal sources are known for being manufactured with little or none quality control resulting in uncertain and unknown formulations. For forensic purposes, apprehended pharmaceuticals have to undergo a process of chemical identification that can be difficult due to its complex matrix. In this sense, application of assisted energies in the extraction step such as microwave irradiation can be a promising method to increase the recuperation of the target molecules of the sample. Therefore, the aim of this research was to identify four slimming agents apprehended in Brazil by means of visual inspection, Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry and Gas Chromatography – Mass Spectrometry. Moreover, the efficiency of solid-liquid extraction and microwave-assisted extraction was compared. It should be noted that our work was one of the few to use Differential Scanning Calorimetry and the application of microwave irradiation in the analysis of apprehended materials. Results showed that the majority of the samples was counterfeit being composed of one or several adulterants or contaminants. Initially, visual inspection resourcefully screened the slimming agents for possible signs of falsification, however it failed to detect fraudulent products that were very similar to veridical medicines. Sequentially, Fourier Transform Infrared Spectroscopy detected functional groups present in the samples while the presence or absence of the alleged active ingredients were successfully measured with Differential Scanning Calorimetry and, thus, providing a full chemical screening of the apprehended materials. Gas Chromatography- Mass Spectrometry confirmed the presence of adulterants such as caffeine, fluoxetine and phenolphthalein as well as contaminants such as sulfurol in the falsified samples. Finally, comparison of extraction procedures indicated that microwave-assisted extraction increased the recovery of compounds detected in chromatographic analysis to a greater extent than solid-liquid extraction.  相似文献   
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Abstract: The design and preliminary characterization of a novel sensor for drugs of abuse, DETECHIP®, is described in this proof‐of‐concept note. Combining both colorimetric and fluorimetric assays, DETECHIP® is suitable for lab and field use. More than a conventional spot test which provides a single “yes or no” answer, DETECHIP® provides twenty responses for a more complete characterization of suspect material. This is accomplished by visually noting colorimetric and fluorescent changes of carefully selected dyes upon the addition of test analytes, including drugs of abuse, with respect to controls. Color and fluorescence changes are recorded numerically so that a 20 digit identification code can be constructed for comparison of test analytes and known compounds. DETECHIP® is applicable to a variety of drugs, both plant‐derived and synthetic, addressing the need to use several different spot tests simultaneously for a single sample.  相似文献   
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