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941.
为了分析某水电站导流隧洞的围岩稳定性,选取影响围岩稳定性的一些主要因素,如岩石质量指标、湿抗压强度、完整性系数、结构面强度系数、地下水渗流量,引入评分机制来评价定性因素对围岩稳定的影响.利用模糊数学原理建立模糊综合评判模型进行分析,获得了与实际情况相一致的结果.  相似文献   
942.
高校后勤文化建设是高校后勤职工按照“三服务、三育人”的宗旨,在长期的管理、服务过程中逐渐形成的具有后勤特色的思想理念、价值标准、管理模式、行为规范以及与之相联系的各项制度的总和。是落实党的“始终代表中国先进文化前进方向”的具体体现,是推进后勤改革与发展的迫切需要,也是打造一支高素质后勤队伍的根本途径。本文就高校后勤文化建设问题,从遵循的原则、实施的内容以及方法、要求等方面进行了扼要的阐述。  相似文献   
943.
This study provides an update on a quantitative method for immature age estimation based on postnatal deciduous mandibular tooth length. Two known sex and age skeletal collections from Western Europe were sampled (n = 97). Linear regression models for age estimated were calculated for each individual tooth, each sex, and sex combined sample using classical calibration. Prediction errors, residuals, and percentage of individuals whose real age fell within the 95% prediction interval were calculated. The teeth which develop earlier in life, the incisors and the first molar, showed the greatest precision, while the canine showed the least. This method has greater applicability to archeological skeletons or to children in developing countries than for use in North American or European forensic contexts. The method can be applied to incomplete or poorly preserved remains of unknown sex, particularly when dental radiographs are not an option or when teeth have been removed from the alveolus or crypt.  相似文献   
944.
Law enforcement agencies routinely sample for gunshot residue (GSR) by bulk techniques and often submit swabs taken from other surfaces besides the hands of the suspect shooter. This study aims to establish the prevalence of antimony, barium, and lead on normally handled automobile surfaces by graphite furnace atomic absorption analysis. No positives were determined on 50 sampled automobile surfaces above cutoff (positive) from background levels. Transfers of GSR particles from shooter hands to automobile surfaces were found to potentially allow for positive GSR determinations, but such transfers seem to be dependent on the shooting conditions and length of GSR exposure. We determined that our bulk analysis method yields an overall 87.94 ± 5.52% extraction efficiency from cotton swabs, while the LOQ determinations strengthening the fact that bulk analysis methods are valid and valuable tools for GSR investigations.  相似文献   
945.
A trace code pattern location measurement approach is proposed. It includes a method that can precisely extract the trace code pattern to identify the color laser printer or photocopier class. In this study, we collected 379 samples from 15 brands, including 129 models and 196 printers or photocopiers. The trace code pattern class is identified. Four class characteristics are used to identify the print source: (i) the relation between the pattern and print output direction; (ii) observation of the shape features from among the trace code pattern units; (iii) the feature arrangement from among the trace code pattern units; and (iv) the arrangement relation of the trace code pattern. Blind testing shows that the accuracy of the proposed method is approximately 96.9% for the Questioned Document Examiners, and 84.3% in the non‐Questioned Document Examiners. It is thus an effective technique for determining a print's color laser printer or photocopier source class.  相似文献   
946.
Police organizations are historically and predominantly male organizations; as such, the purpose of this study is to examine the role of women in Irish policing. The literature review will analyze gender-specific organizational literature, focused on the United States. Theoretical components include biological determination and social constructivism in the policing context. The study is conducted through qualitative interviews and thematic analysis of 10 current and former Gardaí in Ireland. This study empirically contributes to how the organization views gender and how those differences are institutionalized in that Gardaí are treated differently based on their gender.  相似文献   
947.
The emergence of new psychoactive substances (NPS) has raised many issues in the context of law enforcement and public drug policies. In this scenario, interdisciplinary studies are crucial to the decision-making process in the field of criminal science. Unfortunately, information about how NPS affect people's health is lacking even though knowledge about the toxic potential of these substances is essential: the more information about these drugs, the greater the possibility of avoiding damage within the scope of a harm reduction policy. Traditional analytical methods may be inaccessible in the field of forensic science because they are relatively expensive and time-consuming. In this sense, less costly and faster in silico methodologies can be useful strategies. In this work, we submitted computer-calculated toxicity values of various amphetamines and cathinones to an unsupervised multivariate analysis, namely Principal Component Analysis (PCA), and to the supervised techniques Soft Independent Modeling of Class Analogy and Partial Least Square-Discriminant Analysis (SIMCA and PLS-DA) to evaluate how these two NPS groups behave. We studied how theoretical and experimental values are correlated by PLS regression. Although experimental data was available for a small amount of molecules, correlation values reproduced literature values. The in silico method efficiently provided information about the drugs. On the basis of our findings, the technical information presented here can be used in decision-making regarding harm reduction policies and help to fulfill the objectives of criminal science.  相似文献   
948.
A new contactless technique for latent fingerprint visualization on nonporous curved surfaces of circular cross section was introduced by Low et al. (1). The technique utilizes a plane mirror to convey the light rays toward the inspected surfaces for latent fingerprint visualization. This research activity came up as an extension of the previous study which utilized an aluminum plate as the plane mirror to illuminate the inspected surfaces. Dulling spray was used to increase the diffuse component of the reflective aluminum plate. However, the amount of dulling spray will affect the uniformity of the illumination on the inspected curved surfaces. In this study, a study on the new materials for the plane mirror was carried out. Coated aluminum, opal, and ground glass diffusers were selected as the new materials. The performance of the new materials was compared to the aluminum based on the quality of the captured images on various nonporous cylindrical surfaces. A statistical approach known as randomized complete block design was used to design the experiment. The quality of the captured images was obtained using Spectral Image Validation and Verification. Two‐way analysis of variance and Fisher's least significant difference test were used to analyze the quality of the images. From the results of the statistical analysis, coated aluminum has the best performance compared to aluminum, opal, and ground glass diffusers.  相似文献   
949.
目的以随机模拟法对大量混合样本拆分进行统计分析。方法在Identifiler、PP18D、AGCU EX20、PP21、AGCU EX20&AGCU 21+1等5个系统中,使用自主研发软件模拟100万组混合样本,每组逐个拆分,统计平均拆分基因座数(L)和平均拆分组合数(Π)。结果 Identifiler、PP18D、AGCU EX20、PP21、AGCU EX20&AGCU 21+1系统的L分别为4.8、5.8、6.7、7.0、11.1;Π分别为3.71×104、1.06×105、3.34×105、6.40×105、2.48×1012。结论本文结果对于混合样本拆分具有一定的指导意义。  相似文献   
950.
目的研究伤害、疾病和造作所致的鼓膜穿孔特征,为鼓膜穿孔性质的法医学鉴别确认提供理论与方法依据。方法收集全市公安机关法医鉴定2005至2017年度共3720例鼓膜穿孔的案件,通过鼓膜穿孔形态学特征,研究穿孔形成机制与致伤性质。结果鼓膜穿孔的形态特征和形成机制决定穿孔的性质,可据此得出鼓膜穿孔损伤性质的鉴别方法。结论建立了造作性鼓膜穿孔的法医学鉴定方法。  相似文献   
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