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关键词： 互联网经济   洪恩   测度指标  

摘要： 互联网经济是一种新兴的经济形态,更是主导中国经济转型发展的主要抓手。从信息经济、分享经济、互联网经济的概念内涵出发,展开互联网经济范畴的探讨,并构建互联网经济测度的指标体系,为互联网经济的统计与测度提供专业性的建议。

关键词： 研究生教育学   学科范畴   构建理念  

摘要： 阐述了研究生教育学学科内涵,界定了研究生教育学与其他二级学科之间的关系,阐释了主要研究方向和内容。指出了构建研究生教育学的理念,认为创新发展是灵魂,协调发展是路径,绿色发展是保障,开放发展是宗旨,共享发展是关键。

关键词： 语音范畴性知觉   语音意识   早期阅读  

摘要： 本文以200名5至7岁上学儿童为研究对性,测验检查了汉语语音范畴性知觉、语音意识、短时记忆和汉字识别,并通过群体差异比较、分层回归和结构方程建模的方法,探讨了语音范畴性知觉、语音意识和早期阅读的关系。结果发现:(1)5 ~ 7 岁儿童的语音范畴性知觉、语音意识能力随年龄的增加而显著提高;(2)语音范畴性知觉能力与语音意识,特别是韵母意识和音节意识显著相关;(3)语音范畴性知觉不直接影响汉字识别,其对早期阅读的影响是通过语音意识的中介来实现的。

关键词： 思想背景   名实之争   范畴之论  

摘要： 人类认识事物一般经过先命名再分类的过程,这一过程在最初的语言研究中体现为先出现音义之争紧接着如影随形般地出现了对范畴的讨论,前者表现为春秋战国时期的"名""实"之争和古希腊的"本质""约定"之争,后者表现为春秋战国时期的类概念、别名、共名的讨论和古希腊的经典范畴之论。中西语言学研究的这种相似性是由社会、思想乃至认知背景的趋同性决定的,但由于语言类型不同,又各自形成了不同的语文学传统,汉语是语义型语言缺少词形变化,形成了重视分类的语文学研究传统;西方语言是语法型语言,词形变化丰富,形成了重视词形变化的语文学研究传统。

关键词： 熊彼特   创新   哲学分析  

摘要： 熊彼特是创新理论的鼻祖，他的理论对后世影响深远。文章通过马克思主义哲学的批判分析，重新审视熊彼特的创新范畴，揭露出其英雄史观和对资本主义辩护的本质，对于新时期理解创新有一定意义。

关键词： Latent   Missing   Mixture   Nonresponse   Tree  

摘要： Multiple imputation is a common approach for dealing with missing values in statistical databases. The imputer fills in missing values with draws from predictive models estimated from the observed data, resulting in multiple, completed versions of the database. Researchers have developed a variety of default routines to implement multiple imputation;however, there has been limited research comparing the performance of these methods, particularly for categorical data. We use simulation studies to compare repeated sampling properties of three default multiple imputation methods for categorical data, including chained equations using generalized linear models, chained equations using classification and regression trees, and a fully Bayesian joint distribution based on Dirichlet process mixture models. We base the simulations on categorical data from the American Community Survey. In the circumstances of this study, the results suggest that default chained equations approaches based on generalized linear models are dominated by the default regression tree and Bayesian mixture model approaches. They also suggest competing advantages for the regression tree and Bayesian mixture model approaches, making both reasonable default engines for multiple imputation of categorical data. Supplementary material for this article is available online.

关键词： Approximation space   Coproduct   Lower (Upper) natural transformation   Product  

摘要： We consider the class of approximation spaces in the present paper. In this class we define the concept of lower natural transformations, upper natural transformations and natural transformations. We prove that the class of approximation spaces with the lower natural transformations, upper natural transformations and natural transformations form categories which are denoted by $$\underline{\mathbf{Apr }}{} \mathbf S $$ , $$\overline{\mathbf{Apr }}{} \mathbf S $$ and $$\mathbf Apr {} \mathbf S $$ , respectively. We characterize a lower (upper) natural transformation through equivalence classes in an approximation space. We prove that two categories $$\mathbf Apr {} \mathbf S $$ and $$\underline{\mathbf{Apr }}{} \mathbf S $$ are the same. We characterize several kinds of epimorphisms and monomorphisms. In addition, we show that $$\underline{\mathbf{Apr }}{} \mathbf S $$ is a ( ExtrEpi, ExtrMono)-structured. [ABSTRACT FROM AUTHOR]

关键词： alpine meadow   functional diversity   nitrogen and phosphorus fertilization   phylogenetic diversity   productivity   species diversity  

摘要： The relationship between productivity and biodiversity has long been an important issue in ecological research. However, in recent decades, most ecologists have primarily focused on species diversity while paying little attention to functional diversity and phylogenetic diversity (PD), especially in alpine meadow communities following fertilization. In this study, a fertilization experiment involving the addition of nitrogen, phosphorus, and a mixture of both was implemented in an alpine meadow on the Tibetan Plateau. Species diversity, functional diversity, and PD were measured, and the responses of these parameters to the variation in productivity were analyzed. We found that the productivity of alpine plant communities was colimited by N and P, with N being the principal and P being the secondary limiting nutrient. Our results supported the prediction of both the mass ratio hypothesis and niche complementarity hypothesis in fertilized communities, but these hypotheses were not mutually exclusive. The combination of different aspects of biodiversity not only provides a crucial tool to explain the variation in productivity and to understand the underlying mechanisms but also plays an important role in predicting the variation in productivity of -alpine meadow communities, which are sensitive to nutrient enrichment in the context of global change.

关键词： BUILDING materials   WINDOWS   EVALUATION   INSULATING materials   THERMAL insulation -- Evaluation  

摘要： The article reviews several weather-tight products for construction, including H3 FeelSafe windows by the firm Sierra Pacific Windows, the HPI-1000 Building Insulation Blanket by the firm Dow Coming, and the Jetspray Thermal Insulation System by the firm Knauf.

关键词： Computational cognitive neuroscience   Categorization   Visual neuroscience   Basal ganglia   COVIS   HMAX  

摘要： The field of computational cognitive neuroscience (CCN) builds and tests neurobiologically detailed computational models that account for both behavioral and neuroscience data. This article leverages a key advantage of CCN - namely, that it should be possible to interface different CCN models in a plug-and-play fashion - to produce a new and biologically detailed model of perceptual category learning. The new model was created from two existing CCN models: the HMAX model of visual object processing and the COVIS model of category learning. Using bitmap images as inputs and by adjusting only a couple of learning-rate parameters, the new HMAX/COVIS model provides impressively good fits to human category-learning data from two qualitatively different experiments that used different types of category structures and different types of visual stimuli. Overall, the model provides a comprehensive neural and behavioral account of basal ganglia-mediated learning. (C) 2017 Elsevier Ltd. All rights reserved.