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排序方式: 共有410条查询结果,搜索用时 15 毫秒
231.
Ning Zhang Ph.D. Peng Jiang B.S. Weixin Wang M.S. Chengming Wang Ph.D. Lanchi Xie M.S. Zhigang Li B.S. Wei Huang Ph.D. Gaojun Shi B.S. Lei Wang M.S. Yuwen Yan M.S. Shuhui Gao Ph.D. 《Journal of forensic sciences》2020,65(6):2071-2079
Determining the sequence of intersecting lines is a significant issue in the forensic document examination that can reveal the fraud or distinguish between different allegations. Optical coherence tomography (OCT) is a high-resolution cross-sectional imaging technique that has been introduced into forensic science field recently. The potential of OCT as a novel method to determine the sequence of intersecting lines was examined for the first time. In this study, a spectral-domain OCT system with a center wavelength of 900 nm was employed to perform nondestructive examination on determining the sequence of 18 heterogeneous intersecting line samples produced using three types of gel pens and three brands of stamp pad ink seals. Two-dimensional (2D) cross-sectional, and three-dimensional (3D) volumetric images of the intersecting lines were obtained by the OCT system. Several features were noted and analyzed to successfully determine the sequence of all the 18 samples. Blind tests were also conducted to demonstrate the effectiveness of OCT technique. The results illustrate that OCT technology can provide an effective and accurate method for sequencing intersecting lines of gel pen ink and seal ink, which may complement the conventional methods used in the examination of questioned documents. 相似文献
232.
Hannes R. Stephan 《政策研究评论》2020,37(1):64-91
This study applies a narrative lens to policy actors’ discursive strategies in the Scottish debate over fracking. Based on a sample of 226 newspaper articles (2011–2017) and drawing on key elements of the narrative policy framework (NPF), the research examines how policy coalitions have characterized their supporters, their opponents, and the main regulator (Scottish government). It also explores how actors have sought to expand or contain the scope of conflict to favor their policy objectives. Empirically, only the government strives for conflict containment, whereas both pro‐ and anti‐fracking groups prioritize conflict expansion through characterization contests and the diffusion and concentration of the costs/risks and benefits of fracking. In theoretical terms, the study proposes that Sarah Pralle’s conflict management model, which emphasizes symmetrical strategies of conflict expansion by both coalitions, is a potential tool to revise extant NPF expectations about the different narrative strategies of winning and losing coalitions. Moreover, the fact that policy actors mostly employ negatively rather than positively framed characters in their narratives may be a valid expectation for similar policy conflicts, particularly under conditions of regulatory uncertainty. 相似文献
233.
234.
STR基因座等位基因阶梯制备方法尝试 总被引:7,自引:0,他引:7
提高PCR-STR分型技术的准确性。采用荧光标记dNTP掺入法,通过DNA自动测序仪分析不同等位基因片段的长度并确定其命名后,建立并比较扩增产物混合-纯化-重扩增法、琼脂糖凝胶电泳-切割回收纯化DNA-重扩增法、非变性聚丙烯酰胺凝胶电泳-切割回收纯化DNA-重扩增法等3种Ladder制备方法。扩增产物混合-纯化-重扩增法相对较简便、快速、经济。Ladder对照使基因分型数据化,判型准确,重复性好,有利于标准化的实现。 相似文献
235.
Guadalupe Correa-Cabrera 《Labor History》2016,57(3):323-346
Mexico experienced the twentieth century’s first social revolution, a decade of struggle from which emerged a new political regime – a post-revolutionary authoritarian or single-party state one – with President Lázaro Cárdenas as leader by 1934. This post-revolutionary creation included organized labor and peasants, a strong interventionist state and a hegemonic party. Cárdenas’ U.S. counterpart, President Franklin D. Roosevelt, too, was leading dramatic ‘New Deal’ institutional and political revolution in the 1930s and 1940s that spawned a new order of expanded federal government, a renovated Democratic Party, and new movements and interest groups, notably, labor. Both nations featured the same major actors: the state, political parties, and organized labor. Both presidents calculated that preserving labor alliances was crucial for formation and legitimization of a new political order, for maintaining conditions conducive to private-sector investment and economic growth, and for political and economic crisis management. Labor’s growing role reshuffled corporatist alliances within and between international neighbors. This study places Mexico and the United States in comparative context in the early twentieth century and analyzes elite control and inclusion of organized labor in transformation of political landscapes in two different political regimes – a democratic one couched in an established constitution and a post-revolutionary authoritarian one born of a bloody upheaval. 相似文献
236.
237.
Understanding determinants of business location decisions is important from the point of view of economic policy. While the determinants of manufacturing and R&D location have been extensively covered in the literature, in this article we examine a largely neglected question: Under what conditions do manufacturing and R&D have to be physically colocated, that is, when is unbundling the two impossible? In a sample of 241 Finnish industrial firms, we find that unbundling R&D and manufacturing is possible for some companies but indeed a postindustrial myth of sorts for many others. The need for colocation correlates with knowledge intensity of activities: product complexity, process complexity, and industry rate of change, but interestingly enough, not with the size of the firm's R&D budget. 相似文献
238.
郭锦杭 《广东行政学院学报》2000,(4)
本文拟从产权法律保护、专利文献利用、创制激励机制、规范中介机构、引入风险机制以及税收优惠照顾等方面来探讨中国高科技成果的研发及其产业化的法律问题 相似文献
239.
Stephen M. Greenwood BSc Courtney D. Paduch BSc Trevor T. Allen BSc 《Journal of forensic sciences》2023,68(3):828-838
Measuring trajectory angles of bullet defects at a crime scene is an important part of crime scene investigation as these angles can be used for shooting incident reconstructions. The Washington State Patrol Crime Scene Response Team (WSP CSRT) had a desire to report and use measured trajectory angles. To report quantitative measurements, a statement of uncertainty for the measurement must also be reported due to an accreditation requirement through the ANSI National Accreditation Board (ANAB), through which the WSP CSRT is accredited. This evaluation examined the measurement uncertainty of the 3D laser scanning method that the WSP CSRT utilizes for measuring the vertical and azimuth angles from trajectory rods fitted to bullet defects. Three studies were performed which examined the variation of vertical and azimuth angle measurements from trajectory rods on flat surfaces, the variation of azimuth angle measurements from a trajectory rod on a curved surface, and a traceability study with known vertical and azimuth angle measurements. Seven common substrates were selected as target materials and were shot with 9 mm Luger and 0.45 Auto caliber bullets. A vehicle with one bullet defect was utilized for the curved surface study. The WSP's current fleet of Trimble X7 3D laser scanners, the WSP Criminal Investigation Division (CID) Detectives who operate these scanners, and the Forensic Scientists responsible for trajectory rod placement and angle measurements were utilized. An overall measurement uncertainty of +/− 2.6 degrees at an approximate 95% confidence interval was determined for all trajectory angles measured from trajectory rods. 相似文献
240.
《Forensic Science International: Genetics Supplement Series》2019,7(1):197-199
Variant allele 6.2 at locus D19S433 was found in an immigration case involving Syrian family samples where 2 out of 4 children inherited this variant allele from their parents. This variant allele has not been reported previously in the Syrian population since locus D19S433 was not studied. However, records showed the presence of the variant allele 6.2 in Middle Eastern samples of Iraqi, Lebanese, Kuwaiti and Turkish origins. These findings indicate that variant allele 6.2 at locus D19S433 could be specific for the Middle Eastern populations and could be useful in forensic investigation for suspect search. 相似文献