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   39106篇
  免费   623篇
财政金融   6625篇
工业经济   2306篇
计划管理   6441篇
经济学   9185篇
综合类   679篇
运输经济   183篇
旅游经济   353篇
贸易经济   7989篇
农业经济   1150篇
经济概况   4134篇
信息产业经济   47篇
邮电经济   637篇
  2023年   111篇
  2021年   151篇
  2020年   296篇
  2019年   467篇
  2018年   2780篇
  2017年   2568篇
  2016年   1759篇
  2015年   443篇
  2014年   673篇
  2013年   2493篇
  2012年   1221篇
  2011年   2725篇
  2010年   2460篇
  2009年   2238篇
  2008年   2180篇
  2007年   2447篇
  2006年   683篇
  2005年   902篇
  2004年   932篇
  2003年   1051篇
  2002年   680篇
  2001年   565篇
  2000年   505篇
  1999年   418篇
  1998年   487篇
  1997年   427篇
  1996年   428篇
  1995年   355篇
  1994年   361篇
  1993年   346篇
  1992年   347篇
  1991年   360篇
  1990年   330篇
  1989年   239篇
  1988年   251篇
  1987年   257篇
  1986年   252篇
  1985年   351篇
  1984年   343篇
  1983年   327篇
  1982年   279篇
  1981年   282篇
  1980年   276篇
  1979年   272篇
  1978年   219篇
  1977年   178篇
  1976年   182篇
  1975年   157篇
  1974年   146篇
  1973年   145篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
Do local partners' network attributes affect the survival of high-tech international joint ventures (IJV)? How does the effect of network attributes vary in different subnational institutional environments? While the classic economic explanation for IJV formation and subsequent performance draws from the resource-based view (RBV), we add the relational dimension to explain that IJV survival may be affected by local partners’ relation-specific assets within the local network. We test the effect of the local partners’ network attributes as calculated by UCINET (centrality, network status, and structural hole position) on IJV survival. We additionally assert that this relationship is moderated by subnational institutional heterogeneity. Using our sample of 125 IJV dyadic pairs of US multinational enterprises (MNEs) operating in high-tech industries and their local partners in China, we find partial support for our claims.  相似文献   
23.
Kremer and Snyder (Q J Econ 130:1167–1239, 2015) show that demand curves for a preventive and treatment may have different shapes though they target the same disease, biasing the pharmaceutical manufacturer toward developing the lucrative rather than the socially desirable product. This paper tightens the theoretical bounds on the potential deadweight loss from such biases. Using a calibration of the global demand for HIV pharmaceuticals, we demonstrate the dramatically sharper analysis achievable with the new bounds, allowing us to pinpoint potential deadweight loss at 62% of the global gain from curing HIV. We use the calibration to perform policy counterfactuals, assessing welfare effects of government policies such as a subsidy, reference pricing, and price-discrimination ban. The fit of our calibration is good: we find that a hypothetical drug monopolist would price an HIV drug so high that only 4% of the infected population worldwide would purchase, matching actual drug prices and quantities in the early 2000s before subsidies in low-income countries ramped up.  相似文献   
24.
We study the effect of the educational diversity of managers on the performance of team‐managed mutual funds using a large sample of U.S. equity funds from 1994 to 2013. We consider diversity in terms of both final educational degree and field of educational specialisation. We find that, in general, both types of diversity have a positive impact on fund performance, and our results are robust over a wide range of performance metrics and changes in market conditions.  相似文献   
25.
Before 1852 the English patent system operated at both a domestic and a global level, allowing inventors to extend its operation beyond England to the colonies, where it interacted in territories such as Jamaica with a colonial system of patents and grants. It therefore provides one of the few examples of a workable global patent system, and an important case study of the structures that supported the development and circulation of technology within the British Atlantic during the early stages of the industrial revolution. Providing a framework of ‘tiered’ rather than ‘parallel’ powers and jurisdictions, the imperial patent system was a flexible instrument that inventors could use strategically to promote transnational technological innovation, in which people, ideas, and skills moved back and forth between Britain and colonies such as Jamaica. Patenting, which was concentrated in wealthy plantation colonies that sought greater productivity, was therefore a key part of the economic development of empire.  相似文献   
26.
Additive manufacturing (AM) appears to be a particularly attractive use case for blockchain. This research combines inductive in‐depth interviews with the Delphi method to explore what potentials blockchain technology in AM creates, which adoption barriers firms need to overcome, and how supply chains will be affected by the integration of these two potentially disruptive technologies. The results suggest opportunities that are related to intellectual property (IP) rights management, the monitoring of printed parts throughout their lifecycle, process improvements, and data security. The most important barriers for blockchain adoption in AM are an absence of blockchain‐skilled specialists on the labor market, missing governance mechanisms, and a lack of firm‐internal technical expertise. By addressing important limitations of AM, blockchain is expected to improve the competitiveness of AM in parts’ production, catalyzing the trend toward more decentralized manufacturing resulting in more agile, resilient, and flexible supply chains and reduced logistics costs. Beyond that, blockchain‐based AM platforms are expected to enhance supply chain visibility, drive supply chain digitalization, support supply chain finance, and contribute to the emergence of shared factory systems.  相似文献   
27.
We explore the innovation performance benefits of alliances for spin-off firms, in particular spin-offs either from other firms or from public research organizations. During the early years of the emerging combinatorial chemistry industry, the industry on which our empirical analysis focuses, spin-offs engaged in alliances with large and established partners, partners of similar type and size, and with public research organizations, often for different reasons. We seek to understand to what extent alliances of spin-offs with other firms (either large- or small- and medium-sized firms) affected their innovation performance and also how this performance may have been affected by their corporate or public research background. We find evidence that in general alliances of spin-offs with other firms, in particular alliances with large firms, increased their innovation performance. Corporate spin-offs that formed alliances with other firms outperformed public research spin-offs with such alliances. This suggests that, in terms of their innovation performance, corporate spin-offs that engaged in alliances with other firms seemed to have benefitted from their prior corporate background. Interestingly, it turns out that the negative impact of alliances on the innovation performance of public research spin-offs was largely affected by their alliances with small- and medium-sized firms.  相似文献   
28.
In this paper, a structural analysis of hybrid censoring models is presented. This new modularization approach to hybrid censoring models enables a convenient derivation of distributional results. For instance, it allows to derive the exact distribution of the MLEs under an exponential assumption for very complex hybrid scenarios. In order to illustrate the benefit of this idea, we apply it to four new unified progressive hybrid censoring schemes. They are extensions of already proposed unified Type-I/II/III/IV hybrid censoring schemes to progressively Type-II censored data. The resulting analysis shows that the modularization approach provides a powerful, efficient, and elegant tool to study even more complex hybrid censoring models.  相似文献   
29.
Despite the importance of good collaborative relationships in interorganisational projects, clients and contractors often develop adversarial relationships due to perceptual distance about key project issues. In this case study research, we investigated how perceptual distance emerges and changes over time, and how the collaborative relationship between client and contractor develops alongside these dynamics. In this exploration, we built upon agency theory and stewardship theory as complementary perspectives for understanding client-contractor collaborative relationships. We gathered quantitative and qualitative data in two projects, conducting three assessments in about one year. We found that perceptual distance increased and decreased over time, and that a reduction was typically associated with the collaborative relationship being characterized by stewardship rather than agency. These findings suggest that a regular assessment and evaluation of partners’ perceptions of critical project issues is warranted to timely detect and counteract perceptual distance. Moreover, partners would best adopt a stewardship orientation to reduce perceptual distance, although this may take considerable effort given the distributive nature of many pre-project negotiations.  相似文献   
30.
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