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关键词： MEDICAL education examinations   ALCOHOL drinking   DEVIANT behavior   TRAUMATIC psychoses   AFRICAN American graduate students  

摘要： Numerous studies have demonstrated that genetic and environmental factors interact to influence alcohol problems. Yet prior research has primarily focused on samples of European descent and little is known about gene-environment interactions in relation to alcohol problems in non-European populations. In this study, we examined whether and how genetic risk for alcohol problems and peer deviance and interpersonal traumatic events independently and interactively influence trajectories of alcohol use disorder symptoms in a sample of African American students across the college years (N = 1,119;M-age = 18.44 years). Data were drawn from the Spit for Science study where participants completed multiple online surveys throughout college and provided a saliva sample for genotyping. Multilevel growth curve analyses indicated that alcohol dependence genome-wide polygenic risk scores did not predict trajectory of alcohol use disorder symptoms, while family history of alcohol problems was associated with alcohol use disorder symptoms at the start of college but not with the rate of change in symptoms over time. Peer deviance and interpersonal traumatic events were associated with more alcohol use disorder symptoms across college years. Neither alcohol dependence genome-wide polygenic risk scores nor family history of alcohol problems moderated the effects of these environmental risk factors on alcohol use disorder symptoms. Our findings indicated that peer deviance and experience of interpersonal traumatic events are salient risk factors that elevate risk for alcohol problems among African American college students. Family history of alcohol problems could be a useful indicator of genetic risk for alcohol problems. Gene identification efforts with much larger samples of African descent are needed to better characterize genetic risk for alcohol use disorders, in order to better understand gene-environment interaction processes in this understudied population.

关键词： Sustainability   Lean   Architecture, Engineering and Construction  

摘要： Architecture, Engineering and Construction (AEC) industry is classified as a huge consumer of natural resources. It consumes 50% of natural material resources, 40% of energy and is responsible for 50% of total waste. Subsequently, different sustainability indices and environmental certifications have been introduced to AEC. As a result, most construction firms turn to green building designs and acquire different environmental certifications. Recently, the concept of lean management has been introduced to AEC after succeeding in manufacturing. This paper aims at examining the interaction between lean and sustainability principles on the management process of design and construction projects. Towards achieving this aim, two approaches were employed, namely literature review, and a correlation matrix to verify the area of interaction between both lean construction and sustainability principles. Findings took the form of guidelines for AEC companies to help in applying the integrated lean and sustainability principles on managing design and construction processes. (C) 2016 Ain Shams University.

关键词： 化学检验   案件侦破   作用  

摘要： 随着现代科技的进步,化学检验技术以及设备的增强,化学检验所覆盖的领域越来越宽。现代案件复杂多变,合理使用化学检验能够有效帮助案件侦破。本文就化学检验协助案件侦破来说,对指纹、纸张、油墨、炸药、油脂、植物、毒品等多种方向的化学检验进行讨论与分析。

关键词： Semi-supervised learning   Active learning   Sparse coding   Two phase test sample representation classifiers   Pattern classification  

摘要： Two Phase Test Sample Sparse Representation (TPTSSR) classifier was recently proposed as an efficient alternative to the Sparse Representation Classifier (SRC). It aims at classifying data using sparse coding in two phases with h regularization. Although high performances can be obtained by the TPTSSR classifier, since it is a supervised classifier, it is not able to benefit from unlabeled samples which are very often available. In this paper, we introduce a semi-supervised version of the TPTSSR classifier called Semi-supervised Two Phase Test Sample Sparse Representation (STPTSSR). STPTSSR combines the merits of sparse coding, active learning and the two phase collaborative representation classifiers. The proposed framework is able to make any sparse representation based classifier semi-supervised. Extensive experiments carried out on six benchmark image datasets show that the proposed STPTSSR can outperform the classical TPTSSR as well as many state-of-the-art semi-supervised methods.

关键词： Imbalanced classification   Image classification   Generative adversarial nets   Ensemble learning  

摘要： Most image classification algorithms aim to maximize the percentage of class labels that are predicted correctly. These algorithms often missclassify images from minority categories as into the dominant categories. To overcome the issue of unbalanced data for classifying vehicles from traffic surveillance images, we propose a semi supervised pipeline focused on integrating deep neural networks with data augmentation based on generative adversarial nets (GANs). The proposed approach consists of three main stages. In the first stage, we trained several GANs on the original dataset to generate adversarial samples for the rare classes. In the second stage, an ensemble of CNN models with different architectures are trained on the original imbalanced data set, and then a sample selection step is performed to filter out the low-quality adversarial samples. In the final stage, the aforementioned ensemble model is refined on the augmented dataset by adding the selected adversarial samples. Experiments on the highly imbalanced large benchmark "MIOvision Traffic Camera Dataset (MIO-TCD)" classification challenge dataset demonstrate that the proposed framework is able to increase the mean performance of some categories to some extent, while maintaining a high overall accuracy, compared with the baseline.

关键词： 动物检验检疫   食品安全   作用   措施  

摘要： 随着我国社会经济的不断发展，人民生活水平的不断提高，食品安全问题对人类生活的影响越来越显著，它不仅关系到人民群众的生命安全与健康，还会直接影响国家的稳定与发展。因此，动物检验检疫对食品安全至关重要，是保障食品安全的前提，可有效保证动物性食品安全。为将动物检验检疫的作用发挥到极致，本文通过对动物检验检疫于食品安全的作用进行剖析，进而提出相关改进措施，旨在为加强宣传食品安全的重要性，健全动物检验检疫的监管力度提供有效参考。

关键词： 口头变更   劳动合同   法的价值   利益保护  

摘要： 我国《劳动法》明确规定劳动合同的变更应以书面形式,《最高人民法院劳动争议司法解释（四）》对这一规定进行突破,肯定了口头变更劳动合同。口头变更劳动合同适应了我国经济发展的需要,提高了企业的经营自主权,考虑了劳动者的意思表示,但《司法解释（四）》对口头变更劳动合同存在重形式、轻实质的法律漏洞,为企业滥用强势地位提供契机。因此,在肯定口头变更劳动合同的同时,应强调法的正义、自由、秩序价值,平衡劳动者与用人单位的合法权益。这对实现《劳动法》的社会价值具有深远的现实意义。

关键词： 材料智能   智能包装   活性包装   包装设计  

摘要： 目的探索材料智能型包装的分类体系、应用领域与设计实现。方法以现行材料智能型包装案例及文献为基础,对国内外相关的设计实践、专利及相关理论进行系统分析,并根据材料功能特性对其进行分类研究。结果提出了更完善的材料智能型包装的概念、分类、应用领域与设计关键。根据材料本身及其应用在材料智能型包装上表现出来的功能特征,在包装的展示销售、保鲜提醒、商品防伪以及安全防护等方面具有良好的应用前景,重点阐述了功能特征表现较为明显的变色材料包装、发光材料包装、智能水凝胶材料包装、活性包装等,并提出材料在智能型包装设计过程中应着重把握材料选择的恰当性、信息传达的准确性以及图形表现的巧妙性3个方面。结论对材料智能型包装的分类及设计应用进行了细化研究,为智能化包装的拓展研究提供了更多的方向,有利于推动包装产业的转型升级。

关键词： 火工品   运输方案   等级分类   包装   危险性   航天航空   武器装备   运输过程  

摘要： 火工品作为一种敏感、易爆的危险品,主要应用于航天航空、武器装备和民用爆破等关键领域,其作用是否可靠、性能是否稳定直接影响到后续任务的成败.而火工品的包装、运输过程将是对火工品稳定性的第一次考验,能否将火工品安全平稳地送至目的地是按时保质完成试验任务的前提.

关键词： 上市公司   独立董事制度   外生政策冲击   内生性   市场反应  

摘要： 本文借助一个外生政策冲击,通过研究独立董事辞职的市场反应探讨了我国独立董事制度是否有作用。检验结果表明:具有政府官员背景的独立董事辞职后,累计超额收益率为1. 181%,公司价值上升;具有学术机构背景的独立董事辞职后,累计超额收益率为-2. 058%,公司价值下降;进一步研究发现,具有政府官员背景的独立董事辞职的正向市场反应主要来自于代理成本较大的公司,具有学术机构背景的独立董事辞职的市场反应在代理成本不同的公司并没有显著差异。本文结论表明,具有学术机构背景的独立董事能够发挥专家咨询作用,具有政府官员背景的独立董事则降低了公司治理效率,具有负面作用。