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41.
选择目前我国优秀女子跳远运动员的起跳动作作为研究范围,通过运动图像解析系统对在比赛现场得到的相关运动学参数进行了分析.试图找出目前我国女子跳远与世界水平之间的差距,为我国女子跳远运动训练提供参考和依据.分析结果表明,我国女子跳远运动员起跳技术比较成熟,但起跳缓冲技术较差,起跳时间高于世界优秀运动员.  相似文献   
42.
本文阐述了教育技术的产生,在教育活动中的巨大作用,以及在国内外的发展进程和未来趋势。  相似文献   
43.
本文章阐述了楼宇智能化技术课程的体系结构,说明了多媒体课件在该课程教学中的重要意义,详细介绍了多媒体教学的设计过程以及课件的开发环境、过程和实现方法,并讨论了应用多媒体教学的注意之处.  相似文献   
44.
Summary.  We propose covariance-regularized regression, a family of methods for prediction in high dimensional settings that uses a shrunken estimate of the inverse covariance matrix of the features to achieve superior prediction. An estimate of the inverse covariance matrix is obtained by maximizing the log-likelihood of the data, under a multivariate normal model, subject to a penalty; it is then used to estimate coefficients for the regression of the response onto the features. We show that ridge regression, the lasso and the elastic net are special cases of covariance-regularized regression, and we demonstrate that certain previously unexplored forms of covariance-regularized regression can outperform existing methods in a range of situations. The covariance-regularized regression framework is extended to generalized linear models and linear discriminant analysis, and is used to analyse gene expression data sets with multiple class and survival outcomes.  相似文献   
45.
美国现代主义小说家凯萨琳·安恩·波特的小说以其细腻的描写、娴熟的技巧和深邃的思想内涵而深受读者、评论家和作家的赞扬和推崇。她的短篇小说《被背弃的老祖母》采用象征和意识流的写作手法,反映了20世纪初美国社会现实。本文对作品中的象征手法和意识流手法进行了仔细分析。  相似文献   
46.
利用同伦正则化算法探讨了二维对流弥散方程的依赖空间变量的弥散系数反演问题.讨论了初始迭代值、数值微分步长、以及收敛精度对算法实现的影响.数值模拟表明,同伦正则化算法对于此类参数反演问题是一种有效的方法.  相似文献   
47.
A random-effects meta-analysis was undertaken to examine the effectiveness of the pique technique of compliance-gaining. Results indicated an overall significant effect of the pique technique on increased compliance rate across 17 comparisons (r = .27). Moderator analyses showed the technique worked significantly better than controls in gaining compliance when a smaller amount was requested, when the reason for the request was included, and when the technique was used in France. In addition, the pique technique was more successful than control requests in terms of the total amount of money or time given by participants and the percentage of participants inquiring about the requests. Theoretical and practical implications for the success of pique technique are discussed for future research.  相似文献   
48.
A closer look at de-aliasing effects using an efficient foldover technique   总被引:1,自引:0,他引:1  
A. M. Elsawah 《Statistics》2017,51(3):532-557
Foldover techniques are used to reduce the confounding when some important effects (usually lower order effects) cannot be estimated independently. This article develops an efficient foldover mechanism for symmetric or asymmetric designs, whether regular or nonregular. In this paper, we take the uniformity criteria (UC) as the optimality measures to construct the optimal combined designs (initial design plus its corresponding foldover design) which have better capability of estimating lower order effects. The relationship between any initial design and its combined design is studied. A comparison study between the combined designs via different UC is provided. Equivalence between any combined design and its complementary combined design is investigated, which is a very useful constraint that reduce the search space. Using our results as benchmarks, we can implement a powerful algorithm for constructing optimal combined designs. Our work covers as well as gives results better than recent works of about 20 articles in the last few years as special cases. So this article is a good reference for constructing effective designs.  相似文献   
49.
This paper applies stratified random sampling using Neyman allocation to Mangat et al. (1992 Mangat, N.S., Singh, R., Singh, S. (1992). An improved unrelated question randomized response strategy. Cal. Stat. Assoc. Bull. 42:277281.[Crossref] [Google Scholar]) unrelated question randomized response (RR) strategy for both completely truthful reporting and less than completely truthful reporting. It is shown that, for the prior information given, our new model is more efficient in terms of variance (in the case of completely truthful reporting) and mean square error (in terms of less than completely truthful reporting) than Kim and Elam's (2007 Kim, J.M., Elam, M.E. (2007). A stratified unrelated question randomized response model. Stat. Papers 48:215233.[Crossref], [Web of Science ®] [Google Scholar]) model. Numerical illustrations and graphs are also given in support of the present study.  相似文献   
50.
The crux of this article is to estimate the mean of the number of persons possessing a rare sensitive attribute based on the Mangat (1991 Mangat, N.S. (1991). An optional randomized response sampling technique using non–stigmatized attribute. Statistica. 51(4):595602. [Google Scholar]) randomization device by utilizing the Poisson distribution in simple random sampling and stratified sampling. Properties of the proposed randomized response (RR) model have been studied along with recommendations. It is also shown that the proposed model is more efficient than that of Land et al. (2011 Land, M., Singh, S., Sedory, S.A. (2011). Estimation of a rare attribute using Poisson distribution. Statistics. 46(3):351360.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]) in simple random sampling and that of Lee et al. (2013 Lee, G.S., Uhm, D., Kim, J.M. (2013). Estimation of a rare sensitive attribute in stratified sampling using Poisson distribution. Statistics. 47(3):575589.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]) in stratified random sampling when the proportion of persons possessing a rare unrelated attribute is known. Numerical illustrations are also given in support of the present study.  相似文献   
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