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31.
在分析影响河北省高新技术产业发展主要因素的因果关系基础上,依据高新技术产业评价指标体系建立的原则,构建了高新技术产业的数学模型和评价指标体系,从产业投入、产业产出、产业技术创新能力、产业政策环境、科技人力资源的投入力度5个方面分析评价河北省高新技术产业的发展水平,旨在为加速发展河北省高新技术产业提供理论支撑。 相似文献
32.
已有大量文献应用随机前沿分析(SFA)或数据包络分析(DEA)方法对中国工业全要素生产率(TFP)变动进行计算及增长率分解,却未达成共识。基于DEA方法对MalmquistTFP指数进行测算和两层分解的最新进展,对中国1996-2007年的各细分工业行业生产率变动进行测算的结果表明:近12年来,中国各细分工业行业全要素生产率年均增长6.7%,并主要得益于技术前沿的快速进步(11%),但受阻于各行业规模效率下降明显(年均-3.5%),同时纯技术效率年均变动不大(-0.2%)。对行业截面的对比分析可以发现,中国机械电子类行业全要素生产率上升较快,而纺织业等传统优势行业和化工业等资本技术密集型行业的生产率变动低于全行业均值,属于中国工业技术进步的薄弱环节。 相似文献
33.
对参加2008年5月全国青年男排队集训的我国8支重点青年男排队96名运动员年龄、身高、体重及克托莱指数特征进行分析,为我国男排后备队伍选材及训练提供参考。 相似文献
34.
The present study examined the generalizability of the factor pattern, structural parameters, and latent structure of a multidimensional hierarchical model of ethnocultural empathy in males and females. The Scale of Ethnocultural Empathy (SEE) (Wang et al., 2003) was administered to a sample of 610 Italian undergraduates to examine the generalizability and reliability of its factor structure across gender, the psychometric properties and the validity of the scale. Two models were tested through multi-group confirmatory factor analysis (MGCFA): a confirmatory factor-analytic model that hypothesized a multidimensional model of ethnocultural empathy; and a structural equation model that proposed a multidimensional, hierarchical structure with global ethnocultural empathy as a superordinate construct that explained the covariances among the subdomains of the SEE. Both models satisfied multiple criteria for goodness-of-fit with the data. Full metric invariance of factor loadings and factor covariances, and partial invariance of error variances across gender for the four-factors model were supported. Scale reliability was also satisfactory, showing good internal consistency. As regard scale validity, evidence was found for a positive moderate association with a measure of general empathy and a negative high association with a measure of prejudice. Implications are discussed. 相似文献
35.
基于IIG和LSI组合特征提取方法的文本聚类研究 总被引:8,自引:0,他引:8
本文利用改进的信息增益特征选择方法和潜在语义索引技术组合的特征提取方法 ,对文本进行了有效的自动聚类。从语料库中抽取了 2 5 0篇文本 ,首先利用向量空间模型和改进的信息增益特征选择方法 ,构造文本特征向量 ,利用C 均值方法聚类 ,聚类结果准确率、查全率、F measure分别达到 0 .82、0 . 88、0 .83。在此基础上 ,对最优的特征选择结果运用潜在语义索引方法 ,对奇异值分解的结果进行截断处理 ,发现奇异值K取 4 0时聚类结果的准确率、查全率、F measure达到 0 . 95、0. 5 7、0 . 78,在有效地降维的同时 ,大幅度地提高了聚类的准确率。 相似文献
36.
依据发文量和被引量两个计量指标,利用综合指数法测评<大学图书馆学报>1996~2006年的核心著者. 相似文献
37.
A pipelined architecture for distributed text query evaluation 总被引:1,自引:0,他引:1
Alistair Moffat William Webber Justin Zobel Ricardo Baeza-Yates 《Information Retrieval》2007,10(3):205-231
Two principal query-evaluation methodologies have been described for cluster-based implementation of distributed information
retrieval systems: document partitioning and term partitioning. In a document-partitioned system, each of the processors hosts
a subset of the documents in the collection, and executes every query against its local sub-collection. In a term-partitioned
system, each of the processors hosts a subset of the inverted lists that make up the index of the collection, and serves them
to a central machine as they are required for query evaluation.
In this paper we introduce a pipelined query-evaluation methodology, based on a term-partitioned index, in which partially
evaluated queries are passed amongst the set of processors that host the query terms. This arrangement retains the disk read
benefits of term partitioning, but more effectively shares the computational load. We compare the three methodologies experimentally,
and show that term distribution is inefficient and scales poorly. The new pipelined approach offers efficient memory utilization
and efficient use of disk accesses, but suffers from problems with load balancing between nodes. Until these problems are
resolved, document partitioning remains the preferred method.
Alistair Moffat was supported by the Australian Research Council, the ARC Special Research Center for Perceptive and Intelligent
Machines in Complex Environments, and the NICTA Victoria Laboratory.
William Webber and Justin Zobel were supported by the Australian Research Council.
Ricardo Baeza-Yates was supported by Grant P01-029-F from Millennium Initiative of Mideplan, Chile; and by the University
of Melbourne as a visiting scholar at the time this project was undertaken. 相似文献
38.
赵志明 《北京体育大学学报》2007,30(9):1275-1276
运用文献资料法、特尔菲法、主成分和因子分析、R型聚类分析及专业逻辑分析法对所设计的大学男子篮球运动员的篮球意识评价指标进行定性和定量筛选,表明:专家定性筛选后的大超、CUBA运动员篮球意识评价8项一级指标和30项二级指标具有较高的信度和效度,最终通过主成分和因子分析法定量筛选出的5项一级指标和22项二级指标能较全面评价现阶段大超、CUBA男子篮球运动员的篮球意识,可作为评价该群体的篮球意识评价指标. 相似文献
39.
把西南地区少数民族学生的体格营养指数作为一个连续型的随机变量进行正态性检验,研究表明:6个体格营养指数都服从正态分布,根据正态分布理论制定出综合测量少数民族大学生体格营养状的度量标准。 相似文献
40.
Nick Owen 《English in Education》2007,41(2):27-43
The paper proposes a thought experiment written in the spirit of Tom Stoppard's Travesties in which some major contemporary thinkers on and actors of creativity and culture are brought together in the same imagined space through the conceit of a (faulty) memory play. ‘Actors’ are drawn from the National Advisory Committee on Creative and Cultural Education (NACCCE, 19991, the Gulbenkian Committee (1981) and the Joint Council for Education through Art (1957). The paper suggests a series of hypothetical conversations between educationalists from the 1950s to the 2000s who have been engaged with developing arts and cultural education and creativity in our schools. It aims to establish what we have learnt about the discourses of creativity ‐ and what impact this may have had in our classrooms. It concludes with a speculative trial between a Professor Ken Robinson of 1999, adjudged by a Sir Herbert Read of 1957. Nick Owen is a Liverpool‐based film maker and researcher who has recently completed a PhD scholarship at the University of Hull. The scholarship, funded by Creative Partnerships, focused on developing pedagogies for creativity in contexts in which artists and educators work together. 相似文献