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   14093篇
  免费   385篇
财政金融   2977篇
工业经济   1066篇
计划管理   2266篇
经济学   3031篇
综合类   152篇
运输经济   102篇
旅游经济   222篇
贸易经济   2260篇
农业经济   620篇
经济概况   1768篇
信息产业经济   2篇
邮电经济   12篇
  2023年   73篇
  2021年   84篇
  2020年   191篇
  2019年   254篇
  2018年   337篇
  2017年   333篇
  2016年   307篇
  2015年   204篇
  2014年   328篇
  2013年   1591篇
  2012年   382篇
  2011年   466篇
  2010年   425篇
  2009年   438篇
  2008年   401篇
  2007年   356篇
  2006年   331篇
  2005年   262篇
  2004年   270篇
  2003年   273篇
  2002年   273篇
  2001年   276篇
  2000年   291篇
  1999年   294篇
  1998年   300篇
  1997年   266篇
  1996年   225篇
  1995年   219篇
  1994年   235篇
  1993年   240篇
  1992年   262篇
  1991年   253篇
  1990年   201篇
  1989年   181篇
  1988年   165篇
  1987年   162篇
  1986年   167篇
  1985年   237篇
  1984年   253篇
  1983年   244篇
  1982年   213篇
  1981年   195篇
  1980年   170篇
  1979年   169篇
  1978年   157篇
  1977年   134篇
  1976年   123篇
  1975年   139篇
  1974年   99篇
  1973年   100篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Clarence Hatry     
P. S. MANLEY 《Abacus》1976,12(1):49-60
Hatry was one of those curiously un-English figures with whom the English peiodically find themselves unable to cope. J.K. Galbraith, The Great Crash 1929  相似文献   
972.
Upland areas provide UK society with many important functions, goods and services, but have experienced a number of disturbing trends and face an uncertain future. This paper outlines historic, current and future drivers of environmental, economic, socio-cultural and policy change in UK uplands, and assesses how these have affected or are likely to affect ways in which land is used and the provision of ecosystem services. Information is synthesised into scenarios summarising a range of possible futures anticipated for UK uplands to 2060 and beyond. Finally, innovations in science, technology, governance and policy are evaluated that could enable uplands to continue providing key ecosystem services under a range of scenarios. The paper concludes that many upland areas will need to be prepared for significant reductions in grazing and prescribed burning. Conversely, other areas could experience agricultural intensification, for example significant increases in grazing or an expansion of arable or bioenergy crops into upland valleys, due to anticipated increases in global demand for food and energy. These scenarios will take place in the context of climate change. Many may take place together and may interact with each other, with complex and unpredictable implications for the upland environment, economy and society. In this context, a number of advances are needed in science, technology and policy to maintain viable upland communities and the future provision of ecosystem services. These may include funding for ecological and hydrological restoration via carbon offsetting or other means. It may also involve advances in ecosystem service modelling, mapping and valuation, which through stakeholder participation could facilitate more integrated rural planning. New forms of environmental governance need to be explored that can empower those interested in developing upland economies to maintain thriving upland communities, while managing the ecosystem services they provide as efficiently as possible.  相似文献   
973.
This paper presents a diagrammatic solution to the firm's profit-maximizing price discrimination problem in the face of capacity constraints. Airlines, hotels, and other firms practice yield management, allocating fixed capacity to customer groups paying different prices. In these cases, the firm's short-run problem is not a decision about production levels, but it is one of allocating a fixed number of output units among customers. Our diagram shows that the conditions for profit-maximizing price discrimination are very different under these circumstances than in the standard model in which the firm is not constrained by capacity.  相似文献   
974.
975.
Since most agricultural programs employ two or more policy instruments simultaneously, it is notable thai little research has attempted to find optimal instrument combinations and no research exists which evaluates the social costs (unrealized benefits) of combining instruments suboptimally. In our paper we report a simple and feasible method to find optimal policy instrument combinations, and we provide the first general, formal approach to measuring the social costs of suboptimal policy instrument combinations. Our approach is illustrated in an analysis for live major U.S. crops (corn, feed grains, wheat, rice, cotton). The simple model we employ for the illustration suggests that except lor the feed grains program, the observed programs combined policy instruments quite suboptimally. We conclude that agricultural economics research now can and should begin placing increased emphasis on studying optimal policy instrument combinations.  相似文献   
976.
Shocking Stories     
The paper provides a survey of methods that decompose multivariate series into permanent and transitory components by using ideas drawn from the co-integration literature. We adopt a two stage procedure to effect the decomposition. In the first stage a basic set of permanent and transitory components is formed by using standard definitions of the shocks which they are constituted from. The resulting measurements are not unique and further information needs to be employed to get uniqueness. Such information can come in many forms but a particularly important one involves the values of the long-run multipliers for permanent shocks that are available from many calibrated models. A comparison of the methods of effecting the decomposition is performed using a well known data set.  相似文献   
977.
978.
979.
During the 1960s, when it became clear that computers would establish a foothold in business, executives were urged to ensure that the new machines were used effectively. Applying EDP to critical decision and problem areas is still important. However, because of skyrocketing EDP costs and staggering investments in equipment and systems, it now pays to become equally concerned about EDP productivity. Unfortunately, many executives shy away because they lack technical expertise. This is not justified because familiar approaches to cost control that work in other functional areas can be successfully applied to EDP. The author describes how the executive can begin to cope with improving EDP efficiency without getting bogged down in a morass of technical details.  相似文献   
980.
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