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1.
介绍了多自由度刚性杆系静平衡的分析计算。通过调整初始设计中杆件的长度来优化系统。这对于大型起重机前大梁拉杆系统以及一些相关系统的设计优化有一定的实际参考及应用价值 相似文献
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天水市物业管理尚处于起步阶段,存在的问题很多,主要表现在法制建设滞后、建管不分、小区居民对新的物业管理概念认识不清、公司内部人员素质差、服务意识不强、专业人才短缺、资金不足、服务项目少、管理水平低等方面.针对上述问题,起步阶段的天水市物业管理应突出强调服务意识,政府、开发商、物业管理公司、业主四方联动,建立健全各项法规制度,促进天水市物业管理的快速发展,以适应城市现代化建设的要求. 相似文献
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数字图书馆数据安全技术的新进展及应用研究 总被引:1,自引:0,他引:1
数据安全对数字图书馆来讲至关重要,不可或缺.本文对当前国内外数字图书馆的数据安全技术发展进行了追踪和研究,从图书馆数据安全技术最新进展、数据安全技术的具体应用策略二方面对当前数字图书馆的数据安全体系建设进行了全面构建,并对数据安全技术未来的发展进行了简要分析. 相似文献
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The Concept of Record in Interactive, Experiential and Dynamic Environments: the View of InterPARES*
This article presents the concept of electronic record as articulated by the first phase of the InterPARES (International research on Permanent Authentic Records in Electronic Systems) Project (1999–2001) and discusses it in light of the findings of the second phase of the Project (2002–2006). While InterPARES 1 focused on records produced and/or maintained in databases and document management systems, InterPARES 2 examined records produced and/or maintained in interactive, experiential and dynamic environments. The authors describe the characteristics of these environments and of the entities found in them in the course of case studies conducted on systems used for carrying out artistic, scientific and e-government activities, and propose the new concept of record that InterPARES 2 is eleborating, which expands on that formulated by InterPARES 1.The authors would like to thank InterPARES 2 research assistant Randy Preston for his careful editing and constructive criticisms. Some of his suggestions have been incorporated in the text of this article. 相似文献
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Walter Moreira 《Cataloging & classification quarterly》2018,56(1):19-39
Knowledge organization systems have been studied in several fields and for different and complementary aspects. Among the aspects that concentrate common interests, in this article we highlight those related to the terminological and conceptual relationships among the components of any knowledge organization system. This research aims to contribute to the critical analysis of knowledge organization systems, especially ontologies, thesauri, and classification systems, by the comprehension of its similarities and differences when dealing with concepts and their ways of relating to each other as well as to the conceptual design that is adopted. 相似文献
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The purpose of this study is to find a theoretically grounded, practically applicable and useful granularity level of an algorithmically constructed publication-level classification of research publications (ACPLC). The level addressed is the level of research topics. The methodology we propose uses synthesis papers and their reference articles to construct a baseline classification. A dataset of about 31 million publications, and their mutual citations relations, is used to obtain several ACPLCs of different granularity. Each ACPLC is compared to the baseline classification and the best performing ACPLC is identified. The results of two case studies show that the topics of the cases are closely associated with different classes of the identified ACPLC, and that these classes tend to treat only one topic. Further, the class size variation is moderate, and only a small proportion of the publications belong to very small classes. For these reasons, we conclude that the proposed methodology is suitable to determine the topic granularity level of an ACPLC and that the ACPLC identified by this methodology is useful for bibliometric analyses. 相似文献
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The present study aimed to estimate the use of positive and negative parenting practices in Ukraine and explore relationships between parenting practices, intimate partner violence (IPV), alcohol use, and sociodemographics. Parents of children (N = 320) ages 9–16 from three Ukrainian regions answered questions from the Alabama Parenting Questionnaire (APQ), the Revised Conflict Tactics Scales (CTS-R), Family Adaptability and Cohesion Evaluation Scale (FACES), and the Alcohol Use Section of the Drinking and Drug History and Current Use Patterns questionnaire. Ukrainian parents who reported lower use of alcohol, balanced family functioning and lower intimate partner violence were more likely to use positive parenting and less likely to use negative parenting practices. Parents with lower education were more likely to use negative parenting practices. Furthermore, alcohol use, IPV, parent education and higher family income were significantly and indirectly related with positive and negative parenting scores. The model explained 61% of variance in the positive parenting, 67% in the negative parenting. 相似文献
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Benjamin D. Branch 《College & Undergraduate Libraries》2014,21(1):109-114
The role of the library is to assist citizens in skills development critical to national interest and empowerment as literacy ambassadors, in general. Specifically, the work by the Federal Geographic Data Committee (1994) indicates that spatial literacy is for every citizen and not just a set of workforce specialists. Hence, the use of maps in decision making and problem solving will become fundamental to all professions, including library professionals. Thus, a spatial literacy awareness and rationale for such as standard job ability is discussed as a future librarian workforce proficiency and knowledge transfer medium. 相似文献
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Youth involved in the child welfare system experience multiple early adversities that can contribute to increased risk of substance use and delinquency. Although adverse childhood experiences (ACEs) have been associated with poorer behavioral outcomes among youth, less is known about the possible protective factors that may influence the relationship between early adversity and risk-taking behavior. This study examined whether protective adult relationships moderated the link between cumulative ACEs and substance use and delinquency after controlling for demographic characteristics in child welfare-involved youth. The sample included 1054 youth, ages 11–17, from the National Survey of Child and Adolescent Well-Being II who were in the first wave of data collection. Results showed that protective adult relationships moderated the relationship between ACEs and substance use, but not for delinquency. Specifically, under lower levels of protective adult relationships, cumulative ACEs related to increased substance use among youth. Implications for child welfare practices to target youths' support systems are discussed. 相似文献