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181.
Bytewise approximate matching is a relatively new area within digital forensics, but its importance is growing quickly as practitioners are looking for fast methods to screen and analyze the increasing amounts of data in forensic investigations. The essential idea is to complement the use of cryptographic hash functions to detect data objects with bytewise identical representation with the capability to find objects with bytewise similar representations.Unlike cryptographic hash functions, which have been studied and tested for a long time, approximate matching ones are still in their early development stages and evaluation methodology is still evolving. Broadly, prior approaches have used either a human in the loop to manually evaluate the goodness of similarity matches on real world data, or controlled (pseudo-random) data to perform automated evaluation.This work's contribution is to introduce automated approximate matching evaluation on real data by relating approximate matching results to the longest common substring (LCS). Specifically, we introduce a computationally efficient LCS approximation and use it to obtain ground truth on the t5 set. Using the results, we evaluate three existing approximate matching schemes relative to LCS and analyze their performance. 相似文献
182.
3D打印技术如今已受到了社会各界广泛的关注,有着良好的发展前景。然而其本身也具有着一定的治安隐患,如危险物品泛滥、特殊物品复制等。对于3D打印技术,需要进行系统的风险评估,并通过完善机制的构建进行人为控制,以保证其健康发展。这一机制的构建,除了应运用较多的高科技手段外,也应当在管理规范层面做到有序、协调。 相似文献
183.
为了开发一种抗I群4型禽腺病毒(FAd V-4)的亚单位疫苗,选择I群禽腺病毒血清4型流行毒株衣壳蛋白Fiber-2作为保护性抗原蛋白。利用昆虫细胞-杆状病毒系统生产Fiber-2蛋白,通过Westernblot检测重组蛋白的表达情况,利用双向琼脂扩散法检测重组Fiber-2的免疫原性。为了增强亚单位疫苗的免疫保护效果,添加鸡源白细胞介素2(chIL-2)和鸡源γ-干扰素(ch IFN-γ)作为免疫佐剂,与重组Fiber-2单独或混合使用,制备多种形式的亚单位疫苗,并进行动物攻毒保护试验。重组蛋白的Western-blot鉴定结果显示,63 ku处出现Fiber-2蛋白目的条带;双向琼脂扩散试验结果显示,重组蛋白效价达到1∶128,表现出良好的反应原性。动物攻毒保护试验结果显示,单独使用Fiber-2免疫SPF鸡,在50 μg/只的剂量下,可为SPF鸡提供100%的保护效果,以chIL-2和chIFN-γ为免疫佐剂,与重组Fiber-2联合免疫SPF鸡,可显著增强Fiber-2在低剂量(10 μg/只)下的免疫保护效果,上述结果表明重组Fiber-2联合chIL-2和chIFN-γ细胞因子佐剂所制备的亚单位疫苗在抗I群4型禽腺病毒感染领域具有良好的应用前景。 相似文献
184.
Aniseh Bassiri Tabrizi 《European Security》2020,29(3):320-336
ABSTRACT The negotiations with Iran about its nuclear programme have seen the most protracted involvement of the High Representatives of the European Union in a high-profile policy case. This article traces the evolution of the High Representatives’ participation in the negotiations, from the first contacts with the E3 (Germany, France and the United Kingdom) in 2003 to the adoption of the Joint Comprehensive Plan of Action in 2015. It focuses on the institutional role the High Representatives played in relation with the directoires leading the talks with Iran – first the E3 and, since 2006, E3/EU. In this context, it examines the personal and organisational factors that affected the influence each of the three High Representatives (Javier Solana, Catherine Ashton and Federica Mogherini) had in regard to the directoires. The analysis distinguishes specifically between the phases before and after the 2009 Lisbon Treaty. The article shows how similar personal qualities of the three High Representatives in terms of problem-solving and trust-building gave them political capital that enabled them to adopt a fairly constant role as bridge-builders within the directoires and between the directoires and other actors. The reforms of the Lisbon Treaty had only a minor impact. 相似文献
185.
Contemporary research on electoral integrity has focused on the functioning, evaluation, and legitimacy of electoral processes in emerging democracies. By contrast, this study investigates whether a failed election in a well-established democracy can affect individuals' evaluations of the electoral management body, the Election Authority, and whether those evaluations affect satisfaction with democracy. Using the case of a Swedish regional election in 2010 that had to be rerun due to procedural mistakes in the vote handling, we found that, in the short term, individuals’ confidence in the Election Authority was reduced after it was announced that the election had to be rerun because of the mistakes. Subsequently, this decreased confidence was strongly associated with less satisfaction with democracy at the regional and national level. As good news for the authority, after a successful rerun election, confidence rebounded to the levels prior to the failed election. 相似文献
186.
This paper describes the results of using 3D visualization (3DV) in sustainable tourism planning (STP) during the Comcot project in Estonia. Organizers were interviewed on the characteristics of 3DV for STP and on how participants were involved in discourse using 3DV. The study describes experiences from the Setu, Maidla, and Võrtsjärv lake regions of Estonia. The content analysis of the interviews suggested that the precise selection of visualization objects, detalization levels, and user interface characteristics may significantly influence the quality of STP sessions and help to optimize time, financial, and human resources allocated for a project. The coherent design of the 3DV tool and the neutral moderator positively affect the level of participant involvement in STP and support a trusted platform for community decision making. 相似文献
187.
Michael T. Truver PhD Michele M. Crosby PhD Alex T. Gillette MS Sara C. Brogan BS Jennifer L. Hoyer MS Chris W. Chronister PhD Wilson A. Broussard MD Russell S. Vega MD Bruce A. Goldberger PhD 《Journal of forensic sciences》2023,68(4):1419-1424
Novel synthetic opioids contribute considerably to the opioid epidemic, especially with the frequent emergence of structurally similar compounds. This case report describes a fatal intoxication involving 2-methyl AP-237. A 54-year-old Caucasian male was found deceased from an apparent drug overdose. A plastic container labeled “2MAP” and a cut straw were found in the decedent's backpack at the scene. A white substance found in the container tested positive for fentanyl by field testing. According to his medical history, the decedent was treated for a drug overdose 3 years prior to his death. With no diagnostic findings at autopsy, the case was submitted for toxicological analysis. An unknown substance was detected in peripheral blood and urine using gas chromatography with nitrogen phosphorous detection (GC-NPD). Further testing was conducted using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) which confirmed the presence of 2-methyl AP-237 and potential metabolites in blood and urine. Quantitation by GC-NPD revealed concentrations of 2-methyl AP-237 in blood and urine at 480 ng/mL and 4200 ng/mL, respectively. The toxicological analysis also identified and quantitated alprazolam in the blood at 55 ng/mL. Additionally, the metabolism of 2-methyl AP-237 was investigated and three hydroxylated metabolites were identified in peripheral blood and urine. Limited literature is available for the detection and quantitation of 2-methyl AP-237 in postmortem specimens. Given the toxicological findings with unremarkable autopsy findings, this case is an example of a fatal intoxication involving 2-methyl AP-237. 相似文献
188.
When iron-based tools, such as knives or guns, are held, traces of iron can transfer to the skin. However, no previous studies have been published regarding the effect of the elapsed contact time on the transfer of iron species with different valences to the palm. Compared with 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT), 2,4,6-tri(2′-pyridyl)-1,3,5-triazine (TPTZ) was found to exhibit a higher sensitivity to iron(II) spectrophotometrically. This work employed 2,4,6-tri(2′-pyridyl)-1,3,5-triazine (TPTZ) and UV spectrophotometry to determine the amounts of iron(II), iron(III), and total iron transferred to human palms from iron tools. It was found that the palmar moisture level was an important factor in determining the amounts of total iron, including iron(II), transferred to the palm. For identical contact times, the amounts of total iron transferred to the palm was proportional to the palmar moisture, and the difference between the maximum and minimum amounts was 12 μg per hand. However, the amounts of iron(II) transferred to the palm gradually decreased over time for low palmar moisture levels, but steadily increased over time for high palmar moisture levels. Additionally, for average levels of palm moisture, the amounts of iron(II) and iron(III) transferred to the palm gradually decreased and increased, respectively, with longer contact times. Notably, this research could serve as a theoretical basis and guide for the detection of trace iron species with different valences on human palms for criminal investigations. 相似文献
189.
Jennifer M. Welsh 《The international spectator : a quarterly journal of the Istituto affari internazionali》2016,51(2):1-8
AbstractFar from having faded away, ten years after its formal adoption, the responsibility to protect (R2P), is arguably more relevant than ever. In the current overall context of protection crises, heightened in severity by the emergence of violent extremists, R2P has changed the way in which the international community characterises situations that involve protection failures, and has raised expectations about what should occur when atrocity crimes have been committed or are imminent. UN member states now agree that prevention is at the core of R2P, that international action should employ the full range of diplomatic, political and humanitarian measures, and that military force should only be considered as a measure of last resort. While there is continued contestation about particular aspects of R2P – as there is over much older normative advancements, such as human rights – R2P has helped to forge political consensus and build new institutional capacity to prevent and respond to atrocity crimes. 相似文献
190.
Vladimir Baranovsky 《The international spectator : a quarterly journal of the Istituto affari internazionali》2016,51(2):49-69
AbstractRussia’s predominantly suspicious and even negative attitudes toward R2P are closely related to its traditional attachment to the notion of sovereignty, but its reluctance to ‘bless’ the use of force with R2P also serves as a pretext to cover various instrumental goals. Russia’s more assertive foreign policy has exacerbated this trend. Disagreements stem from differences between Russia and the West both in their conceptual approaches to security and in their assessments of specific cases. In particular, Russia has an existential concern over possible application of R2P by extra-regional actors in its immediate post-Soviet vicinity. However, in the conflicts around South Ossetia (2008) and Crimea / Southeastern Ukraine (2014-), there was a noticeable trend to refocus R2P-related arguments in support of Russia’s own actions. By and large, R2P continues to be perceived as a Western attempt to establish certain rules of behaviour which require caution and prudence. Nevertheless, more positive attitudes do not seem impossible. To play a prominent role in the evolving international system, Russia will have to make the R2P segment of its foreign policy more salient and overcome the lag in promoting this concept as a working tool indispensable for cooperative and responsible leadership. 相似文献