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101.
102.
在对Z大学中德合作2+3项目留德学生访谈的基础上,以差异性分析为视角,从教学组织、专业学习和校园生活三个纬度,分析了项目学生对两校园学习的差异性体验,并从文化价值、教育体制、教育投入方面探究其原因,提出了强化国际合作、提升师资能力水平、加大工程实训领域投入等对策。  相似文献   
103.
3G时代图书馆工作面临新的考验。为了应对这一革命性的冲击,高校图书馆要做好数字化的核心准备工作,逐步建立并完善例如“手机图书馆”的建设。一方面可以提高数字化图书的普及与使用率,另一方面也可以在演进的过程中确实保护高校的既得利益。  相似文献   
104.
Objective and Participants: The authors assessed the stability of diet and physical activity and their relationship to weight changes in first-year university women. Methods: They collected anthropometric and body composition data from 101 resident women at the beginning of their first year of college and again at 12 months. The authors obtained physical activity and dietary logs 4 times throughout the year. Results: Caloric intake decreased over 12 months in all participants (p = .01). There was little change in physical activity in participants who lost weight (p = .73, d = .18). Those who gained weight experienced a trend toward decreased physical activity (p = .13, d = .38). A significant Time X Group interaction on physical activity (p = .04) suggests that physical activity patterns differed substantially between individuals who gained weight and those who lost weight. Conclusions: Reduction in physical activity appears to be the defining characteristic in freshman weight gain.  相似文献   
105.
Abstract

Employing Grossman and Helpman’s “protection for sale” model, this article uses data on anti-dumping actions from 1999 to 2009 to perform a quantitative analysis of factors influencing India’s determinations of anti-dumping duties against China, and reveals the micro-formation mechanism of economic conflicts between China and India. We find that the political power of India’s anti-dumping plaintiffs markedly increases the tariff level of its final determinations and that the relationship between the import penetration ratio and duty rates depends upon whether the plaintiffs are politically organized. Further, there is a significant positive correlation between India’s anti-dumping duty rates and its unfavorable trade balance with China. This indicates that in determining anti-dumping duties, Indian authorities are clearly influenced by the political clout of their domestic interest groups. They are also motivated by the desire to keep down China and gain the upper hand in the face-off between the “dragon and the elephant.”  相似文献   
106.
The change from the z of “Student's” 1908 paper to the t of present day statistical theory and practice is traced and documented. It is shown that the change was brought about by the extension of “Student's” approach, by R.A. Fisher, to a broader class of problems, in response to a direct appeal from “Student” for a solution to one of these problems.  相似文献   
107.
J. Anděl  I. Netuka 《Statistics》2013,47(4):279-287
The article deals with methods for computing the stationary marginal distribution in linear models of time series. Two approaches are described. First, an algorithm based on approximation of solution of the corresponding integral equation is briefly reviewed. Then, we study the limit behaviour of the partial sums c 1 η1+c 2 η2+···+c n η n where η i are i.i.d. random variables and c i real constants. We generalize procedure of Haiman (1998) [Haiman, G., 1998, Upper and lower bounds for the tail of the invariant distribution of some AR(1) processes. Asymptotic Methods in Probability and Statistics, 45, 723–730.] to an arbitrary causal linear process and relax the assumptions of his result significantly. This is achieved by investigating the properties of convolution of densities.  相似文献   
108.
In this article, we develop regression models with cross‐classified responses. Conditional independence structures can be explored/exploited through the selective inclusion/exclusion of terms in a certain functional ANOVA decomposition, and the estimation is done nonparametrically via the penalized likelihood method. A cohort of computational and data analytical tools are presented, which include cross‐validation for smoothing parameter selection, Kullback–Leibler projection for model selection, and Bayesian confidence intervals for odds ratios. Random effects are introduced to model possible correlations such as those found in longitudinal and clustered data. Empirical performances of the methods are explored in simulation studies of limited scales, and a real data example is presented using some eyetracking data from linguistic studies. The techniques are implemented in a suite of R functions, whose usage is briefly described in the appendix. The Canadian Journal of Statistics 39: 591–609; 2011. © 2011 Statistical Society of Canada  相似文献   
109.
本文首先定义了三交系、三交系的扩充的概念 ,然后给出了一类三交系的构造方法 ,最后给出了该类三交系的规模的统一公式表示。同时 ,我们得到了一类特殊的三交系判定的充分必要条件  相似文献   
110.
The Color Additives Scientific Review Panel considered whether there was information sufficient to perform a carcinogenic risk assessment on the colors D&C Red No. 19 (R-19), D&C Red No. 37 (R-37), D&C Orange No. 17 (O-17), D&C Red No. 9 (R-9), D&C Red No. 8 (R-8) and FD&C Red No. 3 (R-3) and to evaluate the assessments sent to FDA as part of the petitions for use of the colors for drug and external uses by the Cosmetic, Toiletry and Fragrance Association (CTFA). There is a lack of human data concerning the colors for making a human health assessment, so the assessments are based upon the extrapolation of animal data. The risk assessments are determined for exposure to single chemicals. Excluded from consideration are possible effects from exposure to multiple chemicals, such as co-carcinogenesis, promotion, synergism, antagonism, etc. In the light of recent efforts in establishing a consensus in risk assessment, the Panel has determined that the CTFA assessments for R-10, O-17, and R-9 are consistent with present acceptable usages, although it questions some of the assumptions used in the assessments. The Panel identified a number of general assumptions made, and discusses their validity, their impact on total uncertainty, and the potential options to address the gaps in understanding that necessitate the assumption. The Panel also derived revised risk estimates using more "reasonable" assumptions than "worst-case" situations, for 90th percentile and average exposure. For those assumptions that are easily quantifiable, the Panel's estimates are less than an order of magnitude lower than the CTFA risk estimates, indicating that the underestimates and overestimates of the CTFA risk estimates tend to balance each other. The impact of most of the assumptions is not quantifiable. The assessment for R-3 is complicated by the fact that there is no good skin penetrance study for this color. It was assumed that the penetrance is similar to that of another water-soluble xanthene color, R-19. It is expected that the absorption of the color is not likely to exceed that of the smaller molecule, R-19. Therefore, the risk estimates are similar to the CTFA estimates, but with different reasoning. The estimates for R-8 and R-37 are different from the others in that there is a lack of any exposure or toxicological information on these colors.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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