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931.
932.
933.
Current Control of a continuous random variable is investigated without assuming a normal distribution. The sign test is used as test procedure. The parameters of the corresponding control chart are to be determined in such a way that in the long run the expected loss per produced item is minimal. Approximation formulas for the parameters of such an optimum control chart are derived and discussed.  相似文献   
934.
过程思想是一种实质意义上的思想改革,即思维方式的真正变革。在分析并批评了塑造西方高等教育组织的模型——学术性学科模型——的两个前提性假设(即二元论和外部联系论)在自然科学、社会科学诸领域的种种表现及其后果的基础上,文章以生物进化论对基因的正确理解、对环境问题的应对策略的讨论为例,提出一种以事件为核心的、建设性的、整合性的过程教育思想。  相似文献   
935.
该文认为满语构词附加成分-tu很可能来源于蒙古书面语,是在满蒙书面语的相互接触和影响过程中由蒙古语借入满语的。由此,可以看出蒙古书面语对满语产生了很大的影响。  相似文献   
936.
天线罩覆盖的波束近轴场   总被引:2,自引:0,他引:2  
本文根据复射线法对通过介质天线罩的高斯波束场进行近轴近似分析。实空间的轴向复射线追综大大简化了计算过程,而复相位差、反射-传输系数和曲面扩散系数的进一步校正则提供了相当精确的结果。所得数字结果表明,在波束的近轴区域内为获得同样的计算精度,近轴近似法所需要的计算机时间远小于复射线追综法的时间。  相似文献   
937.
Terrorist actions are aimed at maximizing harm (health, psychological, economical, and political) through the combined physical impacts of the act and fear. Immediate and effective response to a terrorist act is critical to limit human and environmental harm, effectively restore facility function, and maintain public confidence. Though there have been terrorist attacks in public facilities that we have learned from, overall our experiences in restoration of public facilities following a terrorist attack are limited. Restoration of public facilities following a release of a hazardous material is inherently far more complex than in industrial settings and has many unique technical, economic, social, and political challenges. For example, there may be a great need to quickly restore the facility to full operation and allow public access even though it was not designed for easy or rapid restoration, and critical information is needed for quantitative risk assessment and effective restoration must be anticipated to be incomplete and uncertain. Whereas present planning documents have substantial linearity in their organization, the “adaptive management” paradigm provides a constructive parallel paradigm for restoration of public facilities that anticipates and plans for uncertainty, inefficiencies, and stakeholder participation. Adaptive management grew out of the need to manage and restore natural resources in highly complex and changing environments with limited knowledge about causal relationships and responses to restoration actions. Similarities between natural resource management and restoration of a public facility after a terrorist attack suggest that integration of adaptive management principles explicitly into restoration processes will result in substantially enhanced and flexible responses necessary to meet the uncertainties of potential terrorist attacks.  相似文献   
938.
The quality of adolescents' relationships with residential parents has been found to predict many different health and behavioral youth outcomes; strong associations have also been found between these outcomes and family processes, and between relationship quality and family processes. Data from Rounds 1–5 of the National Longitudinal Survey of Youth, 1997 were used to examine hypotheses about the influence of the parent–adolescent relationship on subsequent adolescent mental well‐being and delinquency, as mediated by family processes. Using structural equation modeling, we found that the influence of a positive residential parent–adolescent relationship on better mental well‐being and fewer delinquency was entirely mediated by family routines, parental monitoring, and parental supportiveness, net of sociodemographic controls.  相似文献   
939.
The association between marijuana use and depressive symptoms was examined longitudinally in a sample of 622 African American youth, interviewed on six occasions, using hierarchical linear modeling (HLM). We considered whether depressive symptoms predicted changes in marijuana use and vice versa from high school through the transition into young adulthood. We also examined gender differences in these behaviors over time. The results indicated that depressive symptoms predicted later marijuana use only for males. Marijuana use did not predict later depressive symptoms for females or males. These findings are consistent with a unidirectional hypothesis indicating that marijuana use may play a role as mood regulator among young males, but not among females. Research findings also indicate that females with lower depressive symptoms use more marijuana than females who report high depressive symptoms. These findings did not change even after controlling for the effects of using other substances at previous stages, school achievement, and demographics factors. These results suggest that depressive symptoms may be an antecedent of marijuana use among African American males.  相似文献   
940.
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