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   145405篇
  免费   4107篇
  国内免费   76篇
财政金融   26563篇
工业经济   12100篇
计划管理   23545篇
经济学   31005篇
综合类   2560篇
运输经济   1067篇
旅游经济   2570篇
贸易经济   24723篇
农业经济   6698篇
经济概况   18489篇
信息产业经济   10篇
邮电经济   258篇
  2021年   1155篇
  2020年   1887篇
  2019年   2529篇
  2018年   2448篇
  2017年   2766篇
  2016年   2870篇
  2015年   2408篇
  2014年   3755篇
  2013年   15842篇
  2012年   4934篇
  2011年   5173篇
  2010年   4583篇
  2009年   4937篇
  2008年   4707篇
  2007年   3962篇
  2006年   4315篇
  2005年   4219篇
  2004年   3305篇
  2003年   3057篇
  2002年   3001篇
  2001年   2767篇
  2000年   2630篇
  1999年   2481篇
  1998年   2329篇
  1997年   2365篇
  1996年   2208篇
  1995年   2008篇
  1994年   2011篇
  1993年   1978篇
  1992年   2036篇
  1991年   1943篇
  1990年   1830篇
  1989年   1679篇
  1988年   1608篇
  1987年   1609篇
  1986年   1693篇
  1985年   2478篇
  1984年   2350篇
  1983年   2151篇
  1982年   2004篇
  1981年   1941篇
  1980年   1902篇
  1979年   1844篇
  1978年   1629篇
  1977年   1619篇
  1976年   1384篇
  1975年   1275篇
  1974年   1187篇
  1973年   1186篇
  1972年   894篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
771.
Too often companies fall into a trap when developing a list of performance specifications for a new product. Milton Rosenau calls this the best-of-the-best specification trap. The problem arises whenever a company bases a specification on the combination of the best single features observed in available competitive products. When this happens, the new product's design is driven by competition and is not derived from a unique market insight. This may not provide the basis for a sustainable advantage. Sometimes, rumors of competitive improvements may even lead to sudden changes in the specification, creating delays in the development process. A far better goal is to develop a specification that responds to an unrecognized and unfilled user need, one that adds high value to users. His points are illustrated with several examples.  相似文献   
772.
773.
Agricultural trade impasses have again frustrated the GATT process. Interest in preferential/regional trading blocs is increasing. the paper probes the theoretical and empirical consequences of preferential arrangements instead of multilateral liberalization. It concludes that in a second-best world preferential arrangements could either improve or decrease global welfare. For agricultural trade, previous experience suggests that in regional groupings such as the EC trade diversion exceeded trade creation. This results from trade distorting domestic policies. Prospects for liberalization of agricultural trade under either GATT or preferential arrangements are limited. the consequences for small agricultural exporters are not positive.  相似文献   
774.
This paper concerns the behavior of gold and silver prices on a daily, weekly and monthly time span during January 1970 to December 1989. The methodology consists of extracting the predictive power of time series of changes in past prices for obtaining optimal forecasts for next-period changes in prices. Optimizations are made in the context of information theory via minimizing the degree of diversity between the actual and predicted changes in prices. This methodology has merit in that it does not rest on, generally speaking, unacceptable assumptions regarding the shape of the distribution, stationarity of variance or its existence. The behavior of gold and silver prices are studied during peak to trough and trough to peak of the business cycles over 1970–1989. It is generally shown that information contained in past prices of gold and silver does not allow one to predict next-period changes in prices in the short run. However, longer-term predictions are possible. This study further reveals that as the length of the time interval expands, gold prices exhibit a higher degree of dependency on past prices than silver.  相似文献   
775.
776.
777.
The recent revival of interest in the issue of limiting auditors' liability raises questions about the potential effect of such a limitation on auditors' performance. This paper considers the consequences of limited liability from the perspectives of contracting theory and economic arguments. We examine the potential effect of a reduction in auditors' liability on the standard of care or quality of service they provide, emphasising the "calculus of negligence" concept used by Australian courts. We consider the potential impact of reduced liability on the auditor's decision to shirk responsibilities (the moral hazard problem) and on the value placed on audit services. The analysis shows that placing a statutory cap on auditors' liability has the potential to reduce the effectiveness of bonding mechanisms; provide an avenue for divergent behaviour; lower the level of care provided by auditors; and decrease the value of audit services.  相似文献   
778.
779.
780.
The effects of exogenous water and salts on lipid oxidation in ground beef were determined. Deionized water, salts, or both, were added to treatment samples. Salts used were sodium chloride, potassium chloride and sodium sulphate, all at 3% concentration. The Thiobarbituric acid (TBA) test was used to assess lipid oxidation. Addition of water at a 10% or 20% level had no effect on rancidity. Sodium chloride and potassium chloride reduced TBA numbers. Adding water to those samples containing potassium chloride and sodium sulphate raised moisture content.  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