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991.
介绍了一种帽状结构的掺硼金刚石膜热敏电阻器及其制备工艺。使用PCVD方法在Si3N4或Si基片上淀积掺硼金刚石膜,然后在金刚石膜上淀积Ti/Au薄膜以形成欧姆接触电极。结果获得了具有良好温度响应和欧姆接触的金刚石膜热敏电阻器。 相似文献
992.
993.
利用贝塞尔函数的加法公式,巧妙地处理了复宗量贝塞尔函数,把复宗量贝塞尔函数转化成实宗量贝塞尔函数,从而可以利用一般的程序进行数值计算。 相似文献
994.
Chinese version of the OSI: A validation study 总被引:5,自引:0,他引:5
Luo Lu Cary L. Cooper Yen Ching Chen Chia Ho Hsu Hung Luan Wu Jian Bin Shih Chi Hua Li 《Work and stress》1997,11(1):79-86
This article examines the construct validity of the Occupational Stress Indicator (OSI) in its Chinese version as well as its criterion-oriented validity against self-reported data on absenteeism and accidents, using a final sample of 1054 workers in the Chinese manufacturing and power industries. The divergent and convergent validities of five of the OSI scales—Job satisfaction, Physical ill-health, Mental ill-health, Type A behaviour and Control—were examined by a multimethod-multitrait matrix technique. Results indicated that the Chinese OSI had fairly good validity in relation to other well-established measures as well as relevant organizational behaviours. 相似文献
995.
本文讨论了一类完全竞争条件下的市场均衡问题,供给方的生产特征用线性规划模型进行刻划,市场需求函数源于一般经济意义下的模型,它是一系列相互独立的价格变量的函数.我们将此问题归结为线性互补问题,并依此讨论了均衡点的存在性.本文还讨论了一种用二次规划进行刻划的经济问题,并指出此二次规划的K-K-T条件等价于所讨论的线性互补问题. 相似文献
996.
Foulkes AS Azzoni L Li X Johnson MA Smith C Mounzer K Montaner LJ 《The annals of applied statistics》2010,4(3):1476-1497
Assessment of circulating CD4 count change over time in HIV-infected subjects on antiretroviral therapy (ART) is a central component of disease monitoring. The increasing number of HIV-infected subjects starting therapy and the limited capacity to support CD4 count testing within resource-limited settings have fueled interest in identifying correlates of CD4 count change such as total lymphocyte count, among others. The application of modeling techniques will be essential to this endeavor due to the typically non-linear CD4 trajectory over time and the multiple input variables necessary for capturing CD4 variability. We propose a prediction based classification approach that involves first stage modeling and subsequent classification based on clinically meaningful thresholds. This approach draws on existing analytical methods described in the receiver operating characteristic curve literature while presenting an extension for handling a continuous outcome. Application of this method to an independent test sample results in greater than 98% positive predictive value for CD4 count change. The prediction algorithm is derived based on a cohort of n = 270 HIV-1 infected individuals from the Royal Free Hospital, London who were followed for up to three years from initiation of ART. A test sample comprised of n = 72 individuals from Philadelphia and followed for a similar length of time is used for validation. Results suggest that this approach may be a useful tool for prioritizing limited laboratory resources for CD4 testing after subjects start antiretroviral therapy. 相似文献
997.
The evaluation of new processor designs is an important issue in electrical and computer engineering. Architects use simulations to evaluate designs and to understand trade‐offs and interactions among design parameters. However, due to the lengthy simulation time and limited resources, it is often practically impossible to simulate a full factorial design space. Effective sampling methods and predictive models are required. In this paper, the authors propose an automated performance predictive approach which employs an adaptive sampling scheme that interactively works with the predictive model to select samples for simulation. These samples are then used to build Bayesian additive regression trees, which in turn are used to predict the whole design space. Both real data analysis and simulation studies show that the method is effective in that, though sampling at very few design points, it generates highly accurate predictions on the unsampled points. Furthermore, the proposed model provides quantitative interpretation tools with which investigators can efficiently tune design parameters in order to improve processor performance. The Canadian Journal of Statistics 38: 136–152; 2010 © 2010 Statistical Society of Canada 相似文献
998.
公交站台停靠区的排队问题决定了公交车辆的通行能力。把公交中途站台与公交车辆模拟成一个单服务系统、公车到达率 ,两服务率 、 的负指数分布的排队M/M/1/N系统。根据排队论理论,实测计算了北京中关村海淀黄庄、人民大学站点公交车辆排队队长,站内逗留时间等参数。结论为:城市主干道关键站台改造为主、副双公交站台制式以及调整公交线路布设,优化各线路发车频率是花费成本低,畅通成效大的解决站点塞车排队的方法。 相似文献
999.
1000.
统计方法制度是统计工作的基础和根本,是指导开展统计工作的规范和准则。建立适合我国国情的统计方法制度体系是做好统计工作、为社会各界提供高质量数据的重要前提和保障。本文首先介绍了我国现行的统计方法制度体系,总结了其基本特点及存在的问题,然后针对当前统计工作面临的挑战,确立了统计方法制度改革的总体思路和原则,最后提出了统计方法制度改革拟采取的具体措施。 相似文献