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   20637篇
  免费   95篇
  国内免费   12篇
财政金融   3100篇
工业经济   1061篇
计划管理   3336篇
经济学   4627篇
综合类   841篇
运输经济   36篇
旅游经济   56篇
贸易经济   4888篇
农业经济   217篇
经济概况   1959篇
信息产业经济   44篇
邮电经济   579篇
  2024年   4篇
  2023年   34篇
  2022年   64篇
  2021年   93篇
  2020年   117篇
  2019年   76篇
  2018年   2348篇
  2017年   2145篇
  2016年   1277篇
  2015年   193篇
  2014年   220篇
  2013年   291篇
  2012年   742篇
  2011年   2392篇
  2010年   2232篇
  2009年   1764篇
  2008年   1803篇
  2007年   2142篇
  2006年   340篇
  2005年   651篇
  2004年   535篇
  2003年   624篇
  2002年   297篇
  2001年   130篇
  2000年   71篇
  1999年   20篇
  1998年   38篇
  1997年   16篇
  1996年   30篇
  1995年   7篇
  1994年   9篇
  1993年   5篇
  1992年   2篇
  1991年   4篇
  1989年   2篇
  1988年   2篇
  1987年   1篇
  1986年   15篇
  1985年   1篇
  1984年   4篇
  1983年   2篇
  1982年   1篇
排序方式: 共有10000条查询结果,搜索用时 41 毫秒
91.
92.
93.
Security of Big Data is a huge concern. In a broad sense, Big Data contains two types of data: structured and unstructured. Providing security to unstructured data is more difficult than providing security to structured data. In this paper, we have developed an approach to provide adequate security to unstructured data by considering types of data and their sensitivity levels. We have reviewed the different analytics methods of Big Data to build nodes of different types of data. Each type of data has been classified to provide adequate security and enhance the overhead of the security system. To provide security to a data node, and a security suite has been designed by incorporating different security algorithms. Those security algorithms collectively form a security suite which has been interfaced with the data node. Information on data sensitivity has been collected through a survey. We have shown through several experiments on multiple computer systems with varied configurations that data classification with respect to sensitivity levels enhances the performance of the system. The experimental results show how and in what amount the designed security suite reduces overhead and increases security simultaneously.  相似文献   
94.
95.
This systematic review analyses literature on the work of hybrid value creation, i.e. the process of generating additional value by innovatively combining products (tangible component) and services (intangible component). A state of the art report on hybrid value creation is delivered by first systematically identifying and then analyzing 169 publications focusing on hybrid value creation. The identified publications are clustered into eight categories based on their links and interactions and thus a mapping of this evolving field is suggested. A discussion and reflection of the findings with respect to the pervasiveness of literature and the research methodologies used is provided. The paper concludes by identifying some dominant strategic gaps in the overall research landscape and provides directions for future research.  相似文献   
96.
97.
Ansgar Steland 《Metrika》2004,60(3):229-249
Motivated in part by applications in model selection in statistical genetics and sequential monitoring of financial data, we study an empirical process framework for a class of stopping rules which rely on kernel-weighted averages of past data. We are interested in the asymptotic distribution for time series data and an analysis of the joint influence of the smoothing policy and the alternative defining the deviation from the null model (in-control state). We employ a certain type of local alternative which provides meaningful insights. Our results hold true for short memory processes which satisfy a weak mixing condition. By relying on an empirical process framework we obtain both asymptotic laws for the classical fixed sample design and the sequential monitoring design. As a by-product we establish the asymptotic distribution of the Nadaraya-Watson kernel smoother when the regressors do not get dense as the sample size increases.Acknowledgements The author is grateful to two anonymous referees for their constructive comments, which improved the paper. One referee draws my attention to Lifshits paper. The financial support of the Collaborative Research Centre Reduction of Complexity in Multivariate Data Structures (SFB 475) of the German Research Foundation (DFG) is greatly acknowledged.  相似文献   
98.
The setting of the individual X-factor is a core element of every incentive regulation system. The problem faced by the regulator is the choice among a wide variety of methods for setting the individual efficiency objectives. So far no single method could achieve acceptance as best-practice in both scientific research and regulatory practice. The German incentive regulation, which started in January 2009, uses the so called “Best-of-Four Method” to define individual X-factors. The regulator, the Bundesnetzagentur, announced an in-depth evaluation of this method, because it potentially leads to an unacceptable downward bias in setting the individual efficiency objectives. This article illustrates the problems of the Best-of-Four Method and offers alternatives. The author additionally develops a new approach which is based on a multi-stage process, using economical and engineering methods. Finally all alternatives are compared according to various criteria.It can be shown that the complementary usage of Data Envelopment Analysis and Stochastic Frontier Analysis is a reasonable approach to efficiency analysis. But this raises the question how to transform the resulting efficiency scores into individual X-factors. The Best-of-Four Approach is not appropriate because it distorts the X-factors, offers possibilities for strategic behaviour and cannot guarantee comparability of the efficiency objectives. Comparing alternatives shows that no approach clearly dominates all others taking into account all considered criteria. The multi-stage approach offers a possibility of transforming a “Nordic Walking” into an ambitious fitness program while also setting appropriate and comparable individual X-factors.  相似文献   
99.
发展是第一要义,战略尤其重要,战略离不开学习、实践与思考;我国经历了从石油进口国到净进口国的转变,石油工业的实力以及周围环境都已经了巨大变化,我国石油工业的进一步发展需要破除体制机制障碍,深化改革开放。  相似文献   
100.
Building upon the market, institutional, and cultural perspectives, this paper identifies the major impetuses and impediments that affect the professionalization of Chinese family business at the environment, firm, and owner levels. Our integrative framework projects that whether a family business owner will adopt professional managers is largely determined by the relative strength of impetus factors and impediment factors. We then discuss the possible governance choices under different configuration of impetuses and impediments. This theoretical framework is expected to help set the momentum for further conceptual exploration and empirical study in this area.
Hao MaEmail:

Jianjun Zhang   (PhD, University of California at Berkeley) is an assistant professor at Guanghua School of Management, Peking University. His interests include entrepreneurship, firm governance, and political strategy of Chinese private firms. He is the author of Marketization and democracy in China and a number of articles. Hao Ma   (PhD, University of Texas at Austin) is a professor of management at University of Illinois at Springfield, and professor of management and director of Academic Committee at Beijing International MBA Program, China Center for Economic Research, Peking University. His research interests include the nature and cause of competitive advantage, competitive analysis, strategic decision making, leadership style, and the entrepreneurial process, especially the exploration of the above topics in international setting. He has published in Academy of Management Review, Journal of Business Venturing, Journal of International Management, and Organization Dynamics, among others.  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