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   20711篇
  免费   303篇
财政金融   3398篇
工业经济   1332篇
计划管理   3280篇
经济学   4538篇
综合类   414篇
运输经济   92篇
旅游经济   195篇
贸易经济   3723篇
农业经济   855篇
经济概况   3119篇
信息产业经济   4篇
邮电经济   64篇
  2020年   153篇
  2019年   230篇
  2018年   1013篇
  2017年   971篇
  2016年   675篇
  2015年   222篇
  2014年   397篇
  2013年   1458篇
  2012年   597篇
  2011年   1048篇
  2010年   946篇
  2009年   955篇
  2008年   897篇
  2007年   999篇
  2006年   388篇
  2005年   395篇
  2004年   469篇
  2003年   490篇
  2002年   375篇
  2001年   275篇
  2000年   318篇
  1999年   263篇
  1998年   268篇
  1997年   215篇
  1996年   265篇
  1995年   218篇
  1994年   238篇
  1993年   234篇
  1992年   257篇
  1991年   253篇
  1990年   259篇
  1989年   204篇
  1988年   172篇
  1987年   187篇
  1986年   211篇
  1985年   301篇
  1984年   275篇
  1983年   227篇
  1982年   240篇
  1981年   241篇
  1980年   229篇
  1979年   230篇
  1978年   209篇
  1977年   199篇
  1976年   187篇
  1975年   178篇
  1974年   135篇
  1973年   129篇
  1972年   113篇
  1971年   99篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
The performance of service industries in Canada has been lower than that of good industries over the last four decades, with noticeable exceptions such as for railways and telecommunication carriers. Service industries were less economically (and technically) efficient in that they generated less output value (quantity) per hour worked (level and growth) or per combined unit of labour and capital (multifactor productivity growth) than good industries. The relative output price of services declined slightly over time compared with goods. At the disaggregated level, changing relative output prices were substantial and proved to be an important factor explaining the relative satisfactory economic performance of many service industries despite their low technical performance. Nevertheless, the output share of service industries increased over that period, sustained, mainly, by the growing recourse of all firms to outsourcing of services.  相似文献   
12.
Construction kits have played a significant part in nurturing the growth and development of the minds and manipulation-based skills of children (and adults) in formal and non-formal education settings. These kits have origins rooted in the representation of the built world and now have a diversity of form and function, including technical versions with moving parts. This article examines some of the historically based ideas that lie behind the role that kits may have in terms of physical modelling. The article traces the transformation of kits from simple bricks and blocks into more complicated pieces for space-filling and achieving the transfer of forces and motion. This transformation occurred during the Victorian era when the influence of the ideas of educationalists and, perhaps rather strangely, exponents of early aviation, played major roles in determining the diversity of forms of construction kit and modelled possibilities that are now to be seen in classrooms and homes. The article ends with a review of some of the lessons from the past and present that will need to be considered in relation to concrete modelling in schools for the future. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
13.
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   
14.
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   
15.
Futures research includes the problem of generating reasonably exhaustive and plausible scenarios for a given topic, a problem for which there are no truly satisfactory solutions. This article reviews and evaluates a method, field anomaly relaxation, first put forward some 20 years ago. The evaluation is in the context of an illustrative study of political developments in Europe. The research reconstructs and further develops the method and concludes that it has something to offer for scenario generation. Its weaknesses are identified and suggestions for further research are made.  相似文献   
16.
The new urbanism argues that land-use planning should be used to create higher-density development and to promote alternatives to the use of personal automobiles for transportation. The concerns of the new urbanist movement are shown to be misplaced, and the goals of the new urbanism are shown to be in conflict with market incentives, making them difficult to implement in any event. A better policy for more efficient land use would be for governments to plan more effectively for their own infrastructure development while allowing the development of privately-owned land to be guided by market forces.  相似文献   
17.
18.
The current progress of electrification in Russia is clearly insufficient compared with G8 countries. At the same time, economy sectors have a high potential for energy saving. The electricity consumption of households depends on their cash income and the growth rate of electricity tariffs.  相似文献   
19.
20.
This paper examines the spatial patterns of unemployment in Chicago between 1980 and 1990. We study unemployment clustering with respect to different social and economic distance metrics that reflect the structure of agents' social networks. Specifically, we use physical distance, travel time, and differences in ethnic and occupational distribution between locations. Our goal is to determine whether our estimates of spatial dependence are consistent with models in which agents' employment status is affected by information exchanged locally within their social networks. We present non‐parametric estimates of correlation across Census tracts as a function of each distance metric as well as pairs of metrics, both for unemployment rate itself and after conditioning on a set of tract characteristics. Our results indicate that there is a strong positive and statistically significant degree of spatial dependence in the distribution of raw unemployment rates, for all our metrics. However, once we condition on a set of covariates, most of the spatial autocorrelation is eliminated, with the exception of physical and occupational distance. Racial and ethnic composition variables are the single most important factor in explaining the observed correlation patterns. Copyright © 2002 John Wiley & Sons, Ltd.  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