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381.
2002年中国儿童文学理论批评的重要特别是对当下儿童文学热点、焦点问题的深刻关注,2002年中国儿童文学的热点、焦点问题大致在以下数端:关于第六届亚洲儿童文学大会;关于低龄化写作;关于儿童文学的推广;关于科幻文学;关于成长小说等。对当下儿童文学作家作品的批评及文体建设也是这一年关注较多的内容。  相似文献   
382.
违约责任与侵权责任竞合是由于某种违反民事义务的行为既符合违约责任构成要件又符合侵权责任构成要件 ,从而在法律上导致多种民事责任并存和冲突所产生的现象。因此 ,采取责任聚合与自由选择诉因的措施来解决责任竟合 ,以期充分保护受害方权利 ,消灭责任重叠可能导致的不公平 ,合并不重叠部分的责任。  相似文献   
383.
文章从社会和科技的发展出发,对模具专业课程体系改革的相关问题进行了研究,拟定的改革方案已付诸实施,并已取得初步成果.  相似文献   
384.
中日两国一衣带水,相互毗邻,有着两千多年的友好交往历史。在语言文字方面两国人民互相学习,相互影响,有不少相同、相似之处。但其中也有一些看似相同,实际上已经出现差异并具有特色的词汇和习俗,弄清这些词汇和习俗差异对我们学习日语和同日本人交流大有益处。尤其是在日语教学中,把这些词汇与习俗的异同及时渗透给学生,把中日文化的对比融入日语语言教学中,既可大大地活跃课堂气氛,又可提高学生的积极性和交际水平、应用能力。  相似文献   
385.
Summary.  Non-ignorable missing data, a serious problem in both clinical trials and observational studies, can lead to biased inferences. Quality-of-life measures have become increasingly popular in clinical trials. However, these measures are often incompletely observed, and investigators may suspect that missing quality-of-life data are likely to be non-ignorable. Although several recent references have addressed missing covariates in survival analysis, they all required the assumption that missingness is at random or that all covariates are discrete. We present a method for estimating the parameters in the Cox proportional hazards model when missing covariates may be non-ignorable and continuous or discrete. Our method is useful in reducing the bias and improving efficiency in the presence of missing data. The methodology clearly specifies assumptions about the missing data mechanism and, through sensitivity analysis, helps investigators to understand the potential effect of missing data on study results.  相似文献   
386.
Through the use of two central Bakhtinian concepts, authoritative and internally persuasive discourse (word), this paper examines the tension between the ideology of linguistic hegemony as a source of power in the Greek public sphere and the condition of language shift faced by the Albanian‐speaking communities of modern Greece. I argue here that a cautious application of these two notions, which are relevant to linguistic ideology, can reveal crucial aspects of two processes: that of subordination to and that of questioning of the dominant linguistic ideology by local Albanian‐speaking communities. Thus, in language shift contexts, it is possible that no simple relations obtain that place social agents in unquestionable and easily predictable positions. Such an approach proves useful for the sociolinguistic study of threatened language communities.  相似文献   
387.
A test of congruence among distance matrices is described. It tests the hypothesis that several matrices, containing different types of variables about the same objects, are congruent with one another, so they can be used jointly in statistical analysis. Raw data tables are turned into similarity or distance matrices prior to testing; they can then be compared to data that naturally come in the form of distance matrices. The proposed test can be seen as a generalization of the Mantel test of matrix correspondence to any number of distance matrices. This paper shows that the new test has the correct rate of Type I error and good power. Power increases as the number of objects and the number of congruent data matrices increase; power is higher when the total number of matrices in the study is smaller. To illustrate the method, the proposed test is used to test the hypothesis that matrices representing different types of organoleptic variables (colour, nose, body, palate and finish) in single‐malt Scotch whiskies are congruent.  相似文献   
388.
Maximum likelihood estimation and goodness-of-fit techniques are used within a competing risks framework to obtain maximum likelihood estimates of hazard, density, and survivor functions for randomly right-censored variables. Goodness-of- fit techniques are used to fit distributions to the crude lifetimes, which are used to obtain an estimate of the hazard function, which, in turn, is used to construct the survivor and density functions of the net lifetime of the variable of interest. If only one of the crude lifetimes can be adequately characterized by a parametric model, then semi-parametric estimates may be obtained using a maximum likelihood estimate of one crude lifetime and the empirical distribution function of the other. Simulation studies show that the survivor function estimates from crude lifetimes compare favourably with those given by the product-limit estimator when crude lifetimes are chosen correctly. Other advantages are discussed.  相似文献   
389.
Complete and partial diallel cross designs are examined as to their construction and robustness against the loss of a block of observations. A simple generalized inverse is found for the information matrix of the line effects, which allows evaluation of expressions for the variances of the line-effect differences with and without the missing block. A-efficiencies, based on average variances of the elementary contrasts of the line-effects, suggest that these designs are fairly robust. The loss of efficiency is generally less than 10%, but it is shown that specific comparisons might suffer a loss of efficiency of as much as 40%.  相似文献   
390.
通过对学校社会治安状况的调研,弄清校园及周边社会治安综合治理的重点、难点;分析其普遍性和特殊性;弄清校园及周边人、财、物的动态平衡关系,着力提高防范能力,以便对校园及周边实施科学管理,降低治理成本。运用辩证唯物主义的立场、观点和方法掌握其规律性,有针对性地解决高校扩招后学校社会治安综合治理工作的问题,有力保证学校教学、科研工作,从而促进高校改革的顺利进行,为当地政府和学校领导提供高校扩招后学校社会治安综合治理工作的决策依据。  相似文献   
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