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51.
双语教学涉及教育学、心理学、文化人类学、教育政策学等方方面面的研究领域 ,在民族地区民族学校双语教学的有关政策和法规的制定和完善上 ,要充分体现国际多元文化教育的大背景 ,积极发展多元化文化课程研究和构建双语教育的“多元一体格局”。  相似文献   
52.
在甘、青、宁和新疆地区 ,在民间婚礼中 ,曾经活跃着三种婚俗性的民间舞蹈表演。然而 ,随着历史的推进 ,也出现了舞蹈历史兴衰的现象。本文以生活在中国西北地区的撒拉族、回族、维吾尔族的婚礼中的舞蹈为研究对象 ,在大量第一手调查资料、文献资料的基础上 ,试图分析《堆依奥依纳》、《宴席舞》、《纳孜尔库姆》这三种婚俗舞蹈各自兴衰的过程  相似文献   
53.
推行边疆教育是南京国民政府的一项重要举措,在当时取得了一定成效。对此问题的研究具有积极的现实意义。本文对民国以来甘宁青边疆教育研究状况进行简要述评,并提出今后应注重研究的问题。  相似文献   
54.
Abstract

The present study confirms the influential role of a positively and a negatively correlated auxiliary variables in enhancing the precision of estimates of current population mean in two occasion rotation (successive) sampling. Exponential-type estimators of current population mean have been proposed for three different situations: (i) the information on a positively correlated auxiliary variable is readily available on both occasions (ii) the information on a negatively correlated auxiliary variable is readily available on both occasions and (iii) the information on both positively and negatively correlated auxiliary variables are readily available on both the occasions. The characteristics of the proposed estimators have been explored and their efficacious performances are compared with the natural and recent contemporary estimators. Optimum replacement strategies of the proposed estimation procedures have been formulated. Simulation and empirical studies are carried out to justify the proposition of the proposed estimators and appropriate recommendations have been put forward to the survey practitioners.  相似文献   
55.
We consider the blinded sample size re‐estimation based on the simple one‐sample variance estimator at an interim analysis. We characterize the exact distribution of the standard two‐sample t‐test statistic at the final analysis. We describe a simulation algorithm for the evaluation of the probability of rejecting the null hypothesis at given treatment effect. We compare the blinded sample size re‐estimation method with two unblinded methods with respect to the empirical type I error, the empirical power, and the empirical distribution of the standard deviation estimator and final sample size. We characterize the type I error inflation across the range of standardized non‐inferiority margin for non‐inferiority trials, and derive the adjusted significance level to ensure type I error control for given sample size of the internal pilot study. We show that the adjusted significance level increases as the sample size of the internal pilot study increases. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
56.
This article describes how a frequentist model averaging approach can be used for concentration–QT analyses in the context of thorough QTc studies. Based on simulations, we have concluded that starting from three candidate model families (linear, exponential, and Emax) the model averaging approach leads to treatment effect estimates that are quite robust with respect to the control of the type I error in nearly all simulated scenarios; in particular, with the model averaging approach, the type I error appears less sensitive to model misspecification than the widely used linear model. We noticed also few differences in terms of performance between the model averaging approach and the more classical model selection approach, but we believe that, despite both can be recommended in practice, the model averaging approach can be more appealing because of some deficiencies of model selection approach pointed out in the literature. We think that a model averaging or model selection approach should be systematically considered for conducting concentration–QT analyses. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
57.
In this article, we use cumulative residual Kullback-Leibler information (CRKL) and cumulative Kullback-Leibler information (CKL) to construct two goodness-of-fit test statistics for testing exponentiality with progressively Type-II censored data. The power of the proposed tests are compared with the power of goodness-of-fit test for exponentiality introduced by Balakrishnan et al. (2007 Balakrishnan, N., Habibi Rad, A., Arghami, N.R. (2007). Testing exponentiality based on Kullback-Leibler information with progressively type-II censored data. IEEE Transactions on Reliability 56(2):301307.[Crossref], [Web of Science ®] [Google Scholar]). We show that when the hazard function of the alternative is monotone decreasing, the test based on CRKL has higher power and when the hazard function of the alternative is non-monotone, the test based on CKL has higher power. But, when it is monotone increasing the power difference between test based on CKL and their proposed test is not so remarkable. The use of the proposed tests is shown in an illustrative example.  相似文献   
58.
回顾几十年来学术研究的道路,开始把鲁迅研究以专著形式系列化。这里的系列,只能说是“小系”,而不是“大系”。在这基础上,扩大研究领域,撰写关于中国现代小说研究,现代文学史研究的论著,同时进行散文创作,出版几本散文集。学术界的前辈、同辈、后辈的学者,在著作和文章中对我的论著、作品,进行热情的评论、分析,至感。  相似文献   
59.
使用事件研究法,分析了我国公司发行可转换债券的市场反应。研究表明,我国公司发行可转换债券后市场没有出现显著负的反应,与股权再融资的市场反应明显不同,与国外可转换债券发行的市场反应有差异。政府的奖优政策是可转换债券市场反应特殊性的重要原因。  相似文献   
60.
BackgroundIn Ethiopia, maternal health service utilization is still unacceptably low. The societal and cultural factors that constrain women from attending these services have not yet been sufficiently explored. Using qualitative methods, we aimed to explore the factors that delay maternal health service utilization in eastern Ethiopia.MethodA total of 13 audio-recorded focus group discussions were conducted comprising 88 participants. We conducted separate group discussions with reproductive aged women, mothers-in-law, traditional birth attendants, husbands, and Health Extension Workers to capture their knowledge, practices, feelings, thoughts and attitudes towards maternal health service utilization. The recorded sessions were transcribed into the local language and then translated into English for analysis.ResultThe study identified a number of factors that may delay maternal health service utilization. Factors were grouped using the Three Delays model as a framework. Low level of awareness regarding need, poor involvement of husband, perceived absence of health problems, social power, community misperceptions and cultural restrictions, negative attitudes towards male midwives, acceptance of traditional birth attendants and poor social networking were Delay One factors. Lack of physical accessibility and high transportation costs were categorised as Delay Two factors for skilled birth care attendance. Perceived or experienced poor quality of care were categorised as Delay Three factors for both skilled birth and postnatal care utilization.ConclusionDespite the ongoing government measures to improve maternal health service utilization in Ethiopia, numerous factors continue to contribute to delays in service use, which in turn contribute to high maternal mortality.  相似文献   
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