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201.
蒋歆 《现代情报》2006,26(11):146-147,151
从分类标引方法,分类标引专指度、完全度、协调度、一致性和差错率等几个方面叙述了分类标引存在的问题,并提出了改善措施。  相似文献   
202.
广州城市创新能力指标体系设计研究   总被引:2,自引:0,他引:2  
要促进城市创新发展,需要对城市创新能力进行综合评价,发现其优势与不足之处。而城市创新能力评价的首要工作就是设计一套科学、合理的指标体系。通过运用统计调查方法对相关文献资料的分析,总结了城市创新能力指标体系的层级、指标数以及分类维度等方面的规律。研究表明:以往城市创新能力指标体系采用2或3个层级居多,分类维度可以归为7大类、3大分类模式,上层指标数比底层指标数更具有统计规律。在上述研究结论基础上,得出城市创新能力的本质内涵,将广州城市创新能力看成是一个投入-产出系统,提出由创新投入、创新产出、创新主体以及创新环境支撑4位一体的分类维度设计构想,并据此提出了一套广州城市创新能力指标体系。上述研究结果可以给广州乃至其他地方政府作为城市创新能力评价的参考指标,同时也给该领域感兴趣的研究者提供一种新的研究视角。  相似文献   
203.
网络适应性改造对《中图法》未来发展的启示   总被引:2,自引:0,他引:2  
邱君瑞 《情报理论与实践》2001,24(6):434-435,413
The efforts made by OCLC researchers to enhance Dewey Decimal Classification (DDC) so as to adapt it to Web environment are described. From the experience of OCLC researchers, the author puts forward some proposals for the future development of Chinese Library Classification.  相似文献   
204.
法律上,我国的土地分类主要按土地的用途和利益性质两个标准进行。按照用途,土地被分为农用地、建设用地和未利用土地。依土地利益的性质,土地被分为公益性用地和经营性用地。2002年的《土地分类》(试行)中的土地分类以服务于农业生产为主要特征,以生态功能为主的生态用地被作为"其他农用地"对待。2008年的《土地利用现状分类》国家标准设12个一级土地利用类型,也未将生态用地作为独立的地类。为此,法律应明确公益性用地的层次,将生态用地作为独立的地类,且为层次较高的公益性用地。  相似文献   
205.
206.
The estimation of the economic return to education has perhaps been one of the predominant areas of analysis in applied economics for over 50 years. In this short note we consider some of the recent directions taken by the literature, and also some of the blockages faced by both science and policymakers in pushing forward some key issues. This serves by way of introduction to a set of papers for a special issue of the Economics of Education Review.  相似文献   
207.
A straightforward way to prevent students from leaving education without a higher secondary diploma is increasing the compulsory education age. The idea is that, by staying longer in school, more students eventually obtain a higher secondary diploma. This paper examines the impact of a one-year increase in compulsory school-age on dropping out of secondary education by a difference-in-differences analysis. For this, we exploit a recent compulsory education policy reform in the Netherlands. After controlling for confounding factors and observable covariates, we find that the one year increase in compulsory school-age reduces dropout by 2.5 percentage points. The effect, however, is entirely situated in the group non-liable to the policy reform. We observe that native Dutch vocational students, mostly without retention in grade, but also without a higher secondary diploma at hand, more often left school in the immediate period before the policy reform. Given the economic revival at that time, this may reflect anticipation of labor market opportunities.  相似文献   
208.
This paper investigates the relationship between non-parental care and toddlers’ behavioral outcomes using data from Australia. In particular, we explore heterogeneity in the relationship using the unique data on quality attributes: carer/child ratio, share of qualified staff, and expert ratings. The results suggest that full-time non-parental care, particularly center care, is negatively associated with toddlers’ behavioral outcomes. The negative association is however mitigated when centers have a larger number of carers per child. The negative association between non-parental care and behavioral outcomes also appears to be larger for children with better-educated parents.  相似文献   
209.
This study estimates the value of the private and public benefits that accrue to Minnesota residents from state government subsidies to higher education. In 2005, the University of Minnesota and the Minnesota State Colleges and Universities system received $832 million from Minnesota's state government to support educational programs. These subsidies allow these institutions to offer lower tuition rates, increasing the number of Minnesotans with bachelor and graduate degrees. We calculate that removing these subsidies would eventually lead to 14,000 fewer graduate degree holders in Minnesota, and reduce those with bachelor's degrees or “some college” by 42,000. The annual economic cost of these subsidies is about $326 million; this is less than annual state appropriations because most of those appropriations are income transfers from taxpayers to students, not an economic cost. We estimate that the annual value of the benefits of these subsidies is between $531 and $786 million ($381 and $570 million) when a 3% (5%) discount rate is used. We also discuss some of the income distribution consequences.  相似文献   
210.
Child labor is considered a key obstacle to reaching the international commitments of Education For All. However, the empirical evidence on the effects of child labor on educational attainments is mostly limited to static measurements. This paper assesses the consequences of child labor on schooling outcomes over time by employing a three-year longitudinal household data set from Nicaragua. The potential endogeneity of past child labor and school outcomes is addressed through instrumental variables. The time a child dedicates to work is found to have harmful consequences on subsequent educational achievements, even after controlling for previous human capital accumulation and other factors. In particular, working over three hours a day is associated with school failure in the medium term. A distinction by type of work shows that time spent in market production has larger negative effects on school outcomes than time spent performing household chores.  相似文献   
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