首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   494篇
  免费   5篇
  国内免费   41篇
教育   333篇
科学研究   120篇
各国文化   8篇
体育   15篇
综合类   15篇
文化理论   3篇
信息传播   46篇
  2024年   1篇
  2023年   4篇
  2022年   7篇
  2021年   16篇
  2020年   20篇
  2019年   17篇
  2018年   13篇
  2017年   19篇
  2016年   8篇
  2015年   16篇
  2014年   33篇
  2013年   55篇
  2012年   41篇
  2011年   37篇
  2010年   22篇
  2009年   31篇
  2008年   31篇
  2007年   42篇
  2006年   32篇
  2005年   11篇
  2004年   21篇
  2003年   19篇
  2002年   11篇
  2001年   13篇
  2000年   9篇
  1999年   5篇
  1997年   2篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1988年   1篇
排序方式: 共有540条查询结果,搜索用时 15 毫秒
91.
从结构和认知的角度剖析了现代汉语中“吃+NP”类表达模式,认为该类表达为结构构式,其内部存在构式压制现象,主要表现为题元角色的抑制或凸显。本文试以“吃食堂/食堂吃”为例,主要依据“语义相容原则”,在动结构式、“把”字句构式与成分嵌入句构式中观察几种不同的构式压制现象。  相似文献   
92.
本文从我国酒店行业的人才结构与需求状况、传统酒店管理专业校企合作模式中存在的问题等方面,阐述了高职院校酒店管理专业开展校企合作的意义,并对专科(高职)院校酒店管理专业如何进一步深入校企合作模式提出了建议。  相似文献   
93.
In this paper,a new pressure reducing valve(PRV) with an orifice plate is proposed.The main objective is to explain the mechanisms of pressure reduction and energy conversion in the new PRV.A numerical simulation method was used to investigate the PRV internal flow field and to analyze the throttling effects of the orifice plate and the transform of thermal parameters as outlet pressure,outlet temperature,velocity,and superheat.A structure improvement method for the valve body and orifice plate is put forward to reduce energy loss.The governing equations for internal flow numerical simulation are composed of the continuity,momentum,energy and k-ε transport equations,based on isotropic eddy viscosity theory.Different valve plug displacement models were built to describe the double throttling process.Our analysis shows that the steam pressure drops twice and the degree of superheat increases.There are also lots of eddies which clog the flow channel and disturb the steam flow in the valve cavity after the valve plug and the outlet cavity.After modifying the structure,the numerical results show a better performance of steam flow.  相似文献   
94.
当代中国农民的信息获取机会——结构分析及其局限   总被引:3,自引:2,他引:1  
本文以已有研究揭示的农村居民信息劣势以及现有理论对这一劣势的解释局限为背景,试图通过对我国农民信息获取机会的跨历史时期(历时性)和跨领域考察,发展现有信息不平等理论。按照结构分析的思路,本文以相关历史研究成果、统计资料和政策文本为依据,考察了新中国成立以来,农民信息获取机会的变化及其与已知的结构性因素的关联,显示了已知结构性因素无法解释的变化和差异。研究发现,现有理论可以解释城乡在可比指标上的差距,但很难解释农村不同信息设施/服务/资源间的内部差异及时间序列上的变异;要理解这些差异,需要把国家及其构建的权力关系和市场架构作为影响农民信息获取机会的核心因素。本研究根据这一发现并借鉴O'Connar的新国家理论重新阐释了我国农民的信息劣势。  相似文献   
95.
This case-study follows a school as it struggles to prepare for the changes brought about by Curriculum 2000 and the new key skills qualification. It describes the curriculum debate within the senior management team as it balanced the conflicting needs of subject popularity and necessity. It relates how inherent structural flaws were uncovered in the proposed curriculum strategy, how this very failure was used as an opportunity to initiate staff involvement in the design of curriculum structures and how success was subsequently fashioned from the process. It is a story of failure, consideration, reflection and improvement, and offers some insight into the lessons learned by management and teaching staff as they reflect on the process of change and their own participation in it.  相似文献   
96.
Applying two-level structural equation modelling techniques, the current study examined the dimensionality of socio-economic status (SES) and its relationship with mathematics and science performance at student and school levels. Data were drawn from population 2 (13-year-olds) of 17 countries in the Third International Mathematics and Science study (TIMSS). A set of items about the ownership of household materials was used to measure the dimensions of SES. For most of the countries, a general economic dimension and a cultural dimension were identified at the student level. The cultural dimension had the greatest impact on students' mathematics and science achievement. At the school level, however, only a general economic dimension was found in most countries. This dimension was interpreted to represent community wealth. It was found to be highly related to school mean maths-science achievement, except for the countries where an additional cultural dimension is identified. This cultural dimension can be interpreted as the community cultural resources and atmosphere, and is strongly related to average school mathematics and science achievement. The current study confirmed that the ownership of a set of household materials can be used as SES indicators in exploring its multifaceted feature at both individual and school levels. A similar model structure is found in different countries by applying these indicators, despite the fact that the content of the set of household possessions is different. The findings show that the latent structure of SES at individual level is different from that at the school level, and that SES dimensions have different effects on mathematics and science achievement at individual and school levels.  相似文献   
97.
The purpose of this study was to compare the views of Finnish and US preschool teachers, administrators and parents on appropriate educational practices for children aged 3‐5. To obtain a measure of their attitudes toward quality practices with children, a 26‐item instrument was adapted from Developmentally Appropriate Practices in Early Childhood Programs Serving Children from Birth Through Age 8. Researchers in the USA and Finland were asked to administer the instrument to subjects they considered to be ‘representative’ of teachers, administrators and parents in their respective countries. Analysis‐of‐variance procedures were then used to determine the differences in views to quality programmes among the three groups in both countries. No significant differences were found among the three groups in the Finnish sample (F(2,69) = 1.34, p = ns). Among the US group, the parents were found to score significantly less than administrators (F(2,120) = 7.85, p < 0.0006). Multivariate analyses of variance procedures showed that administrators from the two countries did not differ significantly in any of the areas under study. The two areas where teachers tended to differ significantly were those of ‘teaching strategies’ (t = 3.13, df = 100, p = 0.002) and ‘language development’ (t = 3.98, df = 89, p = 0.000). Teachers in the USA tended to take a more structured approach to instruction in preschool programmes, using teacher‐directed (less appropriate) approaches and providing children with (less appropriate) drill and practice on language skills. Parents in Finland appeared more supportive of developmentally appropriate practices than their US counterparts and their views were more generally congruent with those of teachers and administrators. This study suggests that the construct of ‘appropriateness’ of beliefs/practices for children may be of value in comparative international child‐care studies, and it raises the issue of why a greater congruence in beliefs/practices exists in some countries.  相似文献   
98.
This paper examines from a Social Realist perspective a set of issues in the sociology of education regarding the problem of knowledge. It focuses upon the issue of relativism associated with the constructionist approach that since the time of the New Sociology of Education in the 1970s has constituted in different forms the dominant perspective in the field. It identifies features shared between constructionism and the ‘positivist’ approach with which it contrasts itself. It is argued that these two positions have more in common than is often recognized and draws upon Critical Realism as an alternative to both. Social Realism explores the sociological implications of Critical Realism for education.  相似文献   
99.
中国煤炭消费与经济增长的变结构协整分析   总被引:12,自引:3,他引:9  
张兆响  廖先玲  王晓松 《资源科学》2008,30(9):1282-1289
经济增长与能源消费问题已成为理论界研究的热点,而作为煤炭生产和煤炭消费第一大国的中国,研究其煤炭消费和经济增长的关系问题具有重要意义.按照结构突变理论,对中国煤炭消费和经济增长的数据生成过程进行了分析,验证了它们均是由单位根过程所生成的;采用循序检验的方法并运用EViews5.0编程,检验并确定了中国煤炭消费和经济增长的均值突变和趋势突变的变结构点,证明变结构点的发生与中国50多年来的政治经济形式变化非常吻合.在上述分析基础上,利用变结构协整理论研究和建立了反映中国煤炭消费和经济增长长期均衡关系的变结构协整模型,通过模型的预测能力验证,证明变结构协整模型及其预测性能明显优于未考虑结构突变点的模型,也证实了变结构协整分析是反映经济关系和经济结构变化,体现经济系统内部长期均衡关系的新型研究方法.  相似文献   
100.
中国居民间接生活能源消费的结构分解分析   总被引:8,自引:2,他引:6  
李艳梅  张雷 《资源科学》2008,30(6):890-895
居民生活能源消费可分为直接和间接消费两部分,一般来说,后者远远大于前者。因此,在经济快速发展,能源消费迅猛增长的背景下,分析居民间接生活能源消费的变动趋势及原因,对于寻找节能途径与对策具有重要意义。本文以1987年~2002年为样本期,运用投入产出方法,构建结构分解分析模型,对中国居民间接生活能源消费的增长原因进行了实证分析。结果表明:促使间接生活能源消费增加的因素有居民消费总量增加、消费结构变化、城乡消费比例变化和中间生产技术变化,而起到抑制能源消费增加的因素唯有以直接能源消耗系数大幅下降为标志的节能技术进步。可见,由于我国正值工业化和城市化的中期阶段,居民消费变化和产业结构演进都成为能源消费上升的重要拉动因素,因此必须提倡适度合理的消费方式,促进生活节能;同时加快调整以重化工业为主导的产业结构,发挥结构节能效应。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号