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   7911篇
  免费   159篇
财政金融   682篇
工业经济   214篇
计划管理   624篇
经济学   830篇
综合类   47篇
运输经济   16篇
旅游经济   35篇
贸易经济   606篇
农业经济   181篇
经济概况   737篇
水利工程   4097篇
邮电经济   1篇
  2018年   231篇
  2017年   240篇
  2016年   212篇
  2015年   124篇
  2014年   188篇
  2013年   510篇
  2012年   247篇
  2011年   231篇
  2010年   188篇
  2009年   214篇
  2008年   213篇
  2007年   250篇
  2006年   204篇
  2005年   155篇
  2004年   184篇
  2003年   145篇
  2002年   133篇
  2001年   103篇
  2000年   127篇
  1999年   118篇
  1998年   139篇
  1997年   110篇
  1996年   125篇
  1995年   117篇
  1994年   122篇
  1993年   115篇
  1992年   133篇
  1991年   129篇
  1990年   125篇
  1989年   104篇
  1988年   107篇
  1987年   112篇
  1986年   114篇
  1985年   116篇
  1984年   111篇
  1983年   102篇
  1982年   103篇
  1981年   121篇
  1980年   120篇
  1979年   108篇
  1978年   136篇
  1977年   145篇
  1976年   142篇
  1975年   112篇
  1974年   119篇
  1973年   107篇
  1972年   94篇
  1971年   96篇
  1969年   92篇
  1968年   88篇
排序方式: 共有8070条查询结果,搜索用时 31 毫秒
1.
At the hydroelectric unit No. 11 of the Nizhnekamsk hydroelectric power plant, the filling wedges of a rotor were investigated by ultrasound in the free st  相似文献   
2.
Power Technology and Engineering - The work done on the test site to ensure the operational safety of the powerhouse of the Zagorsk PSP-2 after its leveling is described. The controlled...  相似文献   
3.
Power Technology and Engineering - The major results from the survey and geotechnical monitoring during the leveling of the model foundation of the Zagorsk PSP-2 in test site No. 3 are presented....  相似文献   
4.
Power Technology and Engineering - The monitoring of hydraulic structures as high-risk facilities is discussed. Monitoring should ensure the reliability and functioning of a hydraulic structure...  相似文献   
5.
Various aspects of sustainable development and quality of life are considered, including the impact of standardization. Particular attention is paid to the study of the role played by standardization in improving environmental protection. In this connection the significance of standardization is shown as a factor of improving the technological potential of an enterprise and the quality of life. Various approaches to methods for assessing the effective impact of standardization on the quality of life are analyzed.  相似文献   
6.
Water Resources Management - A number of models have been developed to simulate seawater intrusion in coastal aquifers, which differ in the accuracy level and computational demands, based on the...  相似文献   
7.
The general consensus in the volatility forecasting literature is that high-frequency volatility models outperform low-frequency volatility models. However, such a conclusion is reached when low-frequency volatility models are estimated from daily returns. Instead, we study this question considering daily, low-frequency volatility estimators based on open, high, low, and close daily prices. Our data sample consists of 18 stock market indices. We find that high-frequency volatility models tend to outperform low-frequency volatility models only for short-term forecasts. As the forecast horizon increases (up to one month), the difference in forecast accuracy becomes statistically indistinguishable for most market indices. To evaluate the practical implications of our results, we study a simple asset allocation problem. The results reveal that asset allocation based on high-frequency volatility model forecasts does not outperform asset allocation based on low-frequency volatility model forecasts.  相似文献   
8.
9.
10.
Despite the heightened popularity of entrepreneurship education, there remain open questions regarding best practices in co-curricular programs. Using the theory of planned behavior, the authors examine how students’ intention is shaped to increase the likelihood of participation in entrepreneurship co-curricular programs. To the best of the authors’ knowledge, this study is the first to examine the relation between entrepreneurial identity and entrepreneurial intention theory. They find the popular personality trait, openness, is related to ambition, which reveals the interaction between personal elements (personality/identity) and contextual elements (aspirations to success/intention), a novel finding in the literature. This further illustrates the interconnectedness between the theory of planned behavior and the entrepreneurial event model  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