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   15922篇
  免费   336篇
财政金融   3069篇
工业经济   1343篇
计划管理   2645篇
经济学   3361篇
综合类   165篇
运输经济   128篇
旅游经济   301篇
贸易经济   2377篇
农业经济   756篇
经济概况   2109篇
信息产业经济   1篇
邮电经济   3篇
  2021年   111篇
  2020年   177篇
  2019年   235篇
  2018年   339篇
  2017年   318篇
  2016年   307篇
  2015年   207篇
  2014年   349篇
  2013年   1676篇
  2012年   470篇
  2011年   476篇
  2010年   452篇
  2009年   532篇
  2008年   454篇
  2007年   393篇
  2006年   367篇
  2005年   304篇
  2004年   317篇
  2003年   327篇
  2002年   302篇
  2001年   304篇
  2000年   341篇
  1999年   294篇
  1998年   272篇
  1997年   283篇
  1996年   259篇
  1995年   243篇
  1994年   239篇
  1993年   276篇
  1992年   256篇
  1991年   259篇
  1990年   244篇
  1989年   230篇
  1988年   216篇
  1987年   192篇
  1986年   218篇
  1985年   301篇
  1984年   279篇
  1983年   277篇
  1982年   231篇
  1981年   232篇
  1980年   249篇
  1979年   205篇
  1978年   179篇
  1977年   172篇
  1976年   152篇
  1975年   135篇
  1974年   116篇
  1973年   117篇
  1972年   88篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
In contrast to short-term stock trading, portfolio managers are interested in the medium- to long-term peaks and troughs of the stock price cycles as signals to balance their stock portfolios – the predicted trough is the signal to buy the stock and the predicted peak is the signal to sell the stock. As statistical models are generally inadequate or incapable of providing such portfolio balancing signals, we propose using the generic self-organizing fuzzy neural network (GenSoFNN)—a fuzzy neural system – as a tool for portfolio balancing. The network adopts the supervised learning approach to detect inflection points in the stock price cycles, and a modified locally weighted regression algorithm is employed to smooth the stock cycles. The GenSoFNN-based portfolio balancing system was evaluated with experiments conducted using 23 stocks from the New York Stock Exchange and NASDAQ, and the results showed an average profit return of 65.66%. The contributions of the proposed GenSoFNN intelligent portfolio balancing system are twofold: it can be used as an efficient trading solution and it can provide decision support in trading via its generated rules. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
182.
Disruption management in industrial areas consists in dealing with unanticipated events that get the plans deviate from their intended course. The solution results from the design and the maintenance of an operating mode ensuring a relevant deployment of individual recovery behaviours.The paper proposes an approach to minimize the impact of disrupting events on the whole system. It is based on an analysis of disrupting events and the characterization of the recovery process, and on a cooperative repair method for distributed industrial systems. This method is based on a cooperative distributed problem solving approach supported by a multi-agent system framework.  相似文献   
183.
184.
Globalization and technological advances are driving organizations to extend the boundaries of new product development (NPD) teams from traditional colocated settings to dispersed or virtual settings. Virtual NPD teams have a wide array of information and communication technologies (ICTs) at their disposal. ICTs allow team members to communicate and collaborate as they cope with the opportunities and challenges of cross‐boundary work. The purpose of this paper is to explore ICT use by members of virtual NPD teams. This study presents an exploratory test and integration of two competing perspectives of media use in virtual teams: media capacity theories and social dynamic media theories. Specifically, this paper examines the role of task type, organizational context, and ICT type as critical contingency variables affecting ICT use. It also examines how different patterns of ICT use relate to individual perceptions of team performance. The findings from this study of 184 members of virtual NPD teams in three global firms suggest that communication via ICTs in virtual NPD teams is contingent on a range of factors.  相似文献   
185.
The primary objective of this study is to evaluate three variables utilized frequently within the retail grocery industry to gain a differential advantage within a target market. These variables are Trading Stamps, Credit, and Delivery. Essentially, the study seeks to determine whether these differential variables are related to retail strategy and retail store profitability for a selected group of retail grocery stores belonging to a retailer cooperative. The study also seeks to determine if the utilization of the differential variables creates any profitability changes within the basic retailing strategy variables of the researched respondents.  相似文献   
186.
Nonprofit organizations are held to high ethical standards due to their charitable missions serving the common good. Incidents of fiscal mismanagement within the nonprofit sector make it relevant to assay the ethical principles of employees. This study examines the level of Machiavellian propensities of US nonprofit employees. Results indicate Machiavellian propensities do exist in certain nonprofit employees and these employees agree with questionable behavior. Policy makers and oversight agencies may find these results useful in developing corporate governance and accountability measures for nonprofit organizations. Furthermore, board of director members may use these results to monitor employee actions and address management training.  相似文献   
187.
We provide evidence of rational reference-dependent preferences in the proprietary trading of professional traders. We find increased trading effort and risk taking by traders following morning losses. Further analysis provides no evidence of a deterioration in trading performance subsequent to losses, as neither risk-adjusted performance nor trade execution appear to be negatively affected by prior losses. The evidence supports the existence of rational reference-dependent preferences in the form of trader daily income targets: these professional traders exhibit increased work effort subsequent to abnormal morning losses. The evidence is inconsistent with the alternative explanation of costly loss aversion.  相似文献   
188.
This article is geared toward shedding some more light on what may be the next space race and its contours.Space flight is undoubtedly a human achievement of the second half of the 20th century, and probably the most audacious one of the past century. The space race started suddenly in the 1950s and has grown explosively during the following two decades, but decreased steadily after the 1970s. After the 1990s, however, we have seen a shy rebirth of space-related activities, when many other actors (states) entered the stage, adding up to the agonizing role of the two-actor piece that we have witnessed during the so-called Cold War.The opening years of the 21st century provided a more complex narrative for space exploration. At the start of the new millennium a new technosphere [1] emerged, dominated by what is used to be called as the Information and Communications Technologies (ICT), with the Internet playing the leading role among the bandwagon of technological novelties that appeared during the twilight of space activities. In despite of the fact that artificial satellites represent the very backbone of the global communications system, space activities seem to play a secondary role amidst the apparently accelerated rate of change concerning the technological systems of the present technosphere. But, as it is demonstrated in this paper, things are changing, and very probably a renewed space race will unfold in the coming decades.A question may be placed: what happened? Why the Earth stood still with regard to the race toward the cosmos? Answer: futurists, even prestigious ones like Herman Kahn and Arthur Clarke, did not consider the existence of socioeconomic long waves (Kondratieff waves, or K-waves for short) with their two decades long economic downturn, which has contributed to the deceleration of space-related activities.Analyzing the worldwide evolving scenario of space-related activities during the last eighty years under the framework of the succeeding K-waves and applying some technological forecasting tools, namely the logistic analysis, technological surveillance and intensive data mining, scrutinizing more than 7500 events occurred in the period 1930–2010 related with space activities, it is demonstrated that the space race like the one that we have witnessed until now is a natural growth process that has saturated at the dawn of this century. The same analysis demonstrates that a new growth process in this field might be nowadays under way with contours very different from that imagined by futurists and science fiction writers sixty years ago. Also the main trends in the usage of launching vehicles and satellites are framed and discussed in this paper.  相似文献   
189.
190.
Public sector associations have successfully developed and run employee health insurance pools for almost 30 years, providing members with savings and flexibility not available from commercial health insurance carriers. This article looks at the models, technical tools and governance philosophy that have contributed to their success in a very challenging business environment.  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