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   155835篇
  免费   3785篇
  国内免费   42篇
财政金融   26181篇
工业经济   11656篇
计划管理   22234篇
经济学   30189篇
综合类   1580篇
运输经济   974篇
旅游经济   2504篇
贸易经济   23919篇
农业经济   6285篇
经济概况   17328篇
水利工程   16548篇
信息产业经济   8篇
邮电经济   256篇
  2021年   1105篇
  2020年   1828篇
  2019年   2651篇
  2018年   2899篇
  2017年   2958篇
  2016年   3213篇
  2015年   2404篇
  2014年   3824篇
  2013年   16397篇
  2012年   4932篇
  2011年   4880篇
  2010年   4220篇
  2009年   4813篇
  2008年   4498篇
  2007年   4004篇
  2006年   4188篇
  2005年   4180篇
  2004年   3703篇
  2003年   3206篇
  2002年   3188篇
  2001年   3017篇
  2000年   2843篇
  1999年   2742篇
  1998年   2590篇
  1997年   2676篇
  1996年   2518篇
  1995年   2310篇
  1994年   2303篇
  1993年   2313篇
  1992年   2400篇
  1991年   2257篇
  1990年   2087篇
  1989年   1938篇
  1988年   1846篇
  1987年   1850篇
  1986年   1878篇
  1985年   2703篇
  1984年   2592篇
  1983年   2399篇
  1982年   2257篇
  1981年   2194篇
  1980年   2221篇
  1979年   2128篇
  1978年   1918篇
  1977年   1839篇
  1976年   1660篇
  1975年   1499篇
  1974年   1409篇
  1973年   1407篇
  1972年   1102篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
1.
Portuguese Economic Journal - A set of RLS-type models with ARMA and ARFIMA dynamics is estimated and compared in a forecasting exercise with ARFIMA, GARCH and FIGARCH models. It is an extension of...  相似文献   
2.
Growing urbanisation in South Africa is reflected in burgeoning Working class and informal township settlements on the fringes of its major towns and cities. Paired with this is an increasing reliance on cash as the primary means of economic transaction, which has in turn stimulated the growth of micro-enterprise business activities within the township context. This article discusses the findings of an eight-township small-area census which occurred between 2010 and 2013 in Cape Town, Johannesburg, Ekurhuleni and Durban townships representing 250 000 residents. The researchers were able to establish the scope and scale of informal food and drink retailing in these localities. Of the 10 049 micro-enterprises located in the study, some 3966 (or 39% of the total) trade in food. These include enterprises in primary production, fresh produce retailing, grocery retailing from house and spaza shops, and informal foodservice enterprises. Food is the basis for much township informal business and plays an important role in making food increasingly affordable and locally accessible, and in creating cash employment. The article builds on the knowledge base of the township informal economy role in bolstering food security needs for the marginalised.  相似文献   
3.
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   
4.
5.
6.
During patent litigation, pay‐for‐delay (P4D) deals involve a payment from a patent holder of a branded drug to a generic drug manufacturer to delay entry and withdraw the patent challenge. In return for staying out of the market, the generic firm receives a payment, and/or an authorized licensed entry at a later date, but before the patent expiration. We examine why such deals are stable when there are multiple potential entrants. We combine the first‐mover advantage for the first generic with the ability of the branded manufacturer to launch an authorized generic (AG) to show when P4D deals are an equilibrium outcome. We further show that limiting a branded firm's ability to launch an AG before entry by a successful challenger will deter such deals. However, removing exclusivity period for the first generic challenger will not.  相似文献   
7.
8.
This study back-tests a marginal cost of production model proposed to value the digital currency Bitcoin. Results from both conventional regression and vector autoregression (VAR) models show that the marginal cost of production plays an important role in explaining Bitcoin prices, challenging recent allegations that Bitcoins are essentially worthless. Even with markets pricing Bitcoin in the thousands of dollars each, the valuation model seems robust. The data show that a price bubble that began in the Fall of 2017 resolved itself in early 2018, converging with the marginal cost model. This suggests that while bubbles may appear in the Bitcoin market, prices will tend to this bound and not collapse to zero.  相似文献   
9.
10.
The United Nations Watercourses Convention entered into force on 17 August 2014, following a long and complex journey that dates back to 1970 when the UN referred the matter to its legal arm, the International Law Commission. This article follows the Convention through that long and turbulent road, examines its main provisions and analyses the reasons for the delay of its entry into force. It concludes by answering the question of why entry into force of the Convention should indeed matter.  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