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   154025篇
  免费   3749篇
  国内免费   26篇
财政金融   26067篇
工业经济   11634篇
计划管理   22241篇
经济学   30038篇
综合类   1490篇
运输经济   963篇
旅游经济   2498篇
贸易经济   23804篇
农业经济   6166篇
经济概况   17109篇
水利工程   15495篇
信息产业经济   7篇
邮电经济   288篇
  2021年   1079篇
  2020年   1811篇
  2019年   2625篇
  2018年   2739篇
  2017年   2764篇
  2016年   3112篇
  2015年   2381篇
  2014年   3807篇
  2013年   16389篇
  2012年   4808篇
  2011年   4645篇
  2010年   4054篇
  2009年   4708篇
  2008年   4332篇
  2007年   3812篇
  2006年   4144篇
  2005年   4060篇
  2004年   3708篇
  2003年   3195篇
  2002年   3182篇
  2001年   3027篇
  2000年   2845篇
  1999年   2730篇
  1998年   2605篇
  1997年   2654篇
  1996年   2519篇
  1995年   2308篇
  1994年   2332篇
  1993年   2315篇
  1992年   2381篇
  1991年   2243篇
  1990年   2089篇
  1989年   1945篇
  1988年   1848篇
  1987年   1860篇
  1986年   1876篇
  1985年   2679篇
  1984年   2588篇
  1983年   2392篇
  1982年   2262篇
  1981年   2180篇
  1980年   2198篇
  1979年   2110篇
  1978年   1920篇
  1977年   1838篇
  1976年   1650篇
  1975年   1502篇
  1974年   1405篇
  1973年   1409篇
  1972年   1108篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
This paper explores differences in the bidding patterns of entrants and incumbents in road construction auctions. We find that entrants bid more aggressively and win auctions with significantly lower bids than incumbents. The differences in their bidding patterns are consistent with a model of auctions in which the distribution of an entrant's costs exhibits greater dispersion than that of an incumbent's and relations of stochastic dominance in the distributions do not persist for the entire range of estimated costs. We also find that more efficient firms bid, on average, more aggressively and firms with greater backlogs bid less aggressively.  相似文献   
83.
One Pleistocene mystery is why early North Americans eradicated their large, potentially domesticable animals (e.g., horses), whereas early Europeans did not. A commonly‐held hypothesis is that European species were evasive due to co‐evolution with hominids, whereas North American animals were naïve and unable to adapt quickly enough when experienced human hunters arrived from Eurasia. We explore this hypothesis with a paleoeconomic model of co‐evolution that integrates human hunting investments and wildlife population responses. We find that investments in hunting ability, based on the relative scarcity of prey species, could have mattered more than wildlife ‘naivety’ in explaining the extinction.  相似文献   
84.
85.
Despite the prevalence of elective business ethics courses, little research has sought to explain and predict why some students enroll in these courses and while others do not. Using the theory of planned behavior (Ajzen and Madden, 1986) as a theoretical foundation, 178 graduate students in Ireland were surveyed about their intention to sign up for an elective ethics class. Their behavior was measured two months later. The results reveal the power of the theory of planned behavior to explain and predict who takes elective ethics classes.Donna M. Randall is an associate professor and chair in the Department of Management and Systems at Washington State University. Her research interests include business ethics, organizational commitment, and reproductive risk in the work place. Her work has appeared inJournal of Business Ethics, Decision Sciences, Academy of Management Review, Journal of Vocational Behavior, Journal of Business Research, and others.  相似文献   
86.
Dissolved organic carbon (DOC) dynamics were investigated over a two year period in the Upper Rhǒne River to examine the role of side-arms in providing DOC to the main channel in relation to discharge fluctuations, especially floods. Concentrations of DOC are shown to remain low in space and in time (average 1.5 mg ?1) and to be more related to global hydrological events (precipitation) than to any local flushing for backwaters during floods. The results do not support the general assumption that side-arms are the providers of DOC to the main channel.  相似文献   
87.
88.
In this paper we will analyze the relationship between the value and duration moments of a cash flow and movements in the yield curve. We will show that for changes in the yield curve which can be related to tn , the 1st order changes in the net present value of a cash flow are linearly dependent on the n + lth duration moments, and that the 2nd order changes are dependent on the sum of duration moments of order 2 n + 1 and 2 n + 2. We will use this relationship to tilt tracking portfolios so as to protect them against specific changes in the yield curve.  相似文献   
89.
90.
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