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211.
我国各地区现代化进程研究   总被引:4,自引:0,他引:4  
本文根据国际通行的现代化指标体系计算了中国大陆31个省市区的各项现代化指标的重分,采用主成分分析法和聚类分析法评估了各省市区的现代化水平及其分级和分类特征,并在此基础上分析了我国现代化水平的整体特点及地域分异特点。  相似文献   
212.
Professorial entrepreneurship has recently attracted much attention. This paper draws upon historical research, a survey of faculty, and an Internet-based methodology for identifying professorial affiliations with entrepreneurial firms at two of the premier electrical engineering and computer science departments in the US, The University of California, Berkeley and Stanford. We employ the concept of “nested embeddedness” to explain why the faculty members in these two institutions have different levels of entrepreneurship and corporate involvement. EE&CS faculty at both universities were found to be socially embedded in departments and disciplines that supported and placed value on entrepreneurial activities. However, while being embedded in a university environment with a history of success and high level of support for entrepreneurship, EE&CS faculty at Stanford had a significantly greater level of corporate involvement, including the founding of start-ups. Although significantly less than Stanford, the level of corporate involvement among EE&CS faculty at Berkeley was also substantial. This suggests that being embedded in an academic department and disciplines with cultures that are supportive of entrepreneurial activity can help counteract the disincentives created by a university environment that is not strongly supportive of these activities.  相似文献   
213.
Intelligent use of the many diverse forms of data available on the Internet requires new tools for managing and manipulating heterogeneous forms of information. This paper uses WHIRL, an extension of relational databases that can manipulate textual data using statistical similarity measures developed by the information retrieval community. We show that although WHIRL is designed for more general similarity-based reasoning tasks, it is competitive with mature systems designed explicitly for inductive classification. In particular, WHIRL is well suited for combining different sources of knowledge in the classification process. We show on a diverse set of tasks that the use of appropriate sets of unlabeled background knowledge often decreases error rates, particularly if the number of examples or the size of the strings in the training set is small. This is especially useful when labeling text is a labor-intensive job and when there is a large amount of information available about a particular problem on the World Wide Web.
Haym HirshEmail:
  相似文献   
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215.
大学和学院组织模型:历史演化的视角   总被引:4,自引:1,他引:3  
在过去五六十年里,高等教育研究者提出了多种高等教育组织模型,用它们来理解和解释美国大学和学院的组织行为。本文通过建立一个概念框架,试图解释它们的建立和发展过程。在概念框架中,“变化着的环境条件”是第一驱动力,它形成了“学校管理挑战”,影响和改变了“我们對对主要行业的概念”,从而通过它们间接地影响着大学和学院的运行机制。研究者提出的各种大学和学院组织模型就是从不同的侧面反映环境对组织的影响。  相似文献   
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217.
Do preadolescent sport self-concepts influence subsequent sport performance? Longitudinal data (Grades 3, 4, and 6) for young boys and girls (N= 1,135; mean age = 9.67) were used to test reciprocal effects model (REM) predictions that sport self-concept is both a cause and a consequence of sport accomplishments. Controlling prior sport performance (performance-based measures and teacher assessments), prior sport self-concept had positive effects on subsequent sport performance in both Grade 4 and Grade 6 and for both boys and girls. Coupled with previous REM studies of adolescents in the academic domain, this first test for preadolescents in the sport domain supports the generalizability of REM predictions over gender, self-concept domain, preadolescent ages, and the transition from primary to secondary school.  相似文献   
218.
Age differences in decision making indicate that children fail to anticipate outcomes of their decisions. Using heart rate and skin conductance analyses, we tested whether developmental changes in decision making are associated with (a) a failure to process outcomes of decisions, or (b) a failure to anticipate future outcomes of decisions. Children aged 8-10, 12-14, and 16-18 years performed the Hungry Donkey task, a child version of the Iowa Gambling Task, while heart rate and skin conductance activity were continuously recorded. Children aged 16-18 learned to make advantageous choices over task blocks faster than the two younger age groups. Age differences were present for anticipation-related autonomic activity but not outcome-related autonomic activity. The results are interpreted vis-à-vis models of prefrontal cortex maturation.  相似文献   
219.
Two studies were conducted to investigate how 14- to 16-month-old infants select actions to imitate from the stream of events. In each study, an experimenter demonstrated two actions leading to an interesting effect. Aspects of the first action were manipulated and whether infants performed this action when given the objects was observed. In both studies, infants were more likely to imitate the first action when it was physically necessary to generate the effect, and in Study 2 they were also more likely to imitate the action when it was socially cued. It seems that infants' own knowledge of space and causality as well as their sensitivity to others' social signals both contribute to their tendency to imitate actions.  相似文献   
220.
This study examined developmental trends in object and spatial working memory (WM) using heart rate (HR) to provide an index of covert cognitive processes. Participants in 4 age groups (6-7, 9-10, 11-12, 18-26, n=20 each) performed object and spatial WM tasks, in which each trial was followed by feedback. Spatial WM task performance reached adult levels before object WM task performance. The differential developmental trends for object and spatial WM found in this study are taken to suggest that these WM components are separable. Negative performance feedback elicited HR slowing that was more pronounced for adults than for children. The development of performance monitoring as indexed by covert HR slowing following performance feedback contributes to WM performance.  相似文献   
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