全文获取类型
收费全文 | 2230篇 |
免费 | 59篇 |
国内免费 | 14篇 |
专业分类
财政金融 | 159篇 |
工业经济 | 122篇 |
计划管理 | 249篇 |
经济学 | 1114篇 |
综合类 | 83篇 |
运输经济 | 9篇 |
旅游经济 | 23篇 |
贸易经济 | 291篇 |
农业经济 | 58篇 |
经济概况 | 195篇 |
出版年
2024年 | 4篇 |
2023年 | 36篇 |
2022年 | 77篇 |
2021年 | 88篇 |
2020年 | 134篇 |
2019年 | 103篇 |
2018年 | 101篇 |
2017年 | 90篇 |
2016年 | 92篇 |
2015年 | 76篇 |
2014年 | 106篇 |
2013年 | 207篇 |
2012年 | 113篇 |
2011年 | 170篇 |
2010年 | 113篇 |
2009年 | 142篇 |
2008年 | 123篇 |
2007年 | 103篇 |
2006年 | 78篇 |
2005年 | 70篇 |
2004年 | 51篇 |
2003年 | 37篇 |
2002年 | 33篇 |
2001年 | 24篇 |
2000年 | 16篇 |
1999年 | 21篇 |
1998年 | 15篇 |
1997年 | 20篇 |
1996年 | 8篇 |
1995年 | 10篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 7篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1985年 | 2篇 |
1984年 | 12篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有2303条查询结果,搜索用时 15 毫秒
21.
中欧贸易与欧盟技术性贸易壁垒 总被引:1,自引:0,他引:1
近年来,技术性贸易壁垒(TBT)已成为发达国家实施贸易保护主义更为隐蔽、更为有效的手段.作为中国第三大贸易伙伴的欧盟,其实施的各种TBT措施对中国的出口产品产生了严重的影响.因此,必须建立欧盟技术性贸易壁垒预警机制,时时监控其新动向;坚持"以质取胜"的原则,大搞技术创新和产品创新,以更高的产品质量标准和专利注册超越其贸易壁垒. 相似文献
22.
综合地震勘探整体的发展情况,比较细致的论述了地震勘探仪器当前应用的技术现状、基本发展规律、技术关键以及未来仪器技术的发展方向。 相似文献
23.
西方空间集聚—扩散理论及北京城区功能的扩散 总被引:2,自引:0,他引:2
已被世界上许多国家区域经济发展实践验证的西方空间集聚一扩散理论,是对区域经济发展中带有普遍性特征规律的理论表述。以这一理论为基础,结合北京城区集聚不经济的实际,加快北京城区工业企业、事业单位和与此相伴的住宅、商业用房、交通枢纽、第三产业的择情扩散,保证有效扩散的法律、税制、规划、政府职能、中小城镇、乡镇企业的发展和网络建设等相关环境的建设步伐,是促使北京作为国家首都、世界城市、文化名城、宜居城市功能有效发挥和提升京津冀区域经济合作等级的重要步骤。 相似文献
24.
Technological change in energy systems: Learning curves, logistic curves and input-output coefficients 总被引:1,自引:0,他引:1
Learning curves have recently been widely adopted in climate-economy models to incorporate endogenous change of energy technologies, replacing the conventional assumption of an autonomous energy efficiency improvement. However, there has been little consideration of the credibility of the learning curve. The current trend that many important energy and climate change policy analyses rely on the learning curve means that it is of great importance to critically examine the basis for learning curves. Here, we analyse the use of learning curves in energy technology, usually implemented as a simple power function. We find that the learning curve cannot separate the effects of price and technological change, cannot reflect continuous and qualitative change of both conventional and emerging energy technologies, cannot help to determine the time paths of technological investment, and misses the central role of R&D activity in driving technological change. We argue that a logistic curve of improving performance modified to include R&D activity as a driving variable can better describe the cost reductions in energy technologies. Furthermore, we demonstrate that the top-down Leontief technology can incorporate the bottom-up technologies that improve along either the learning curve or the logistic curve, through changing input-output coefficients. An application to UK wind power illustrates that the logistic curve fits the observed data better and implies greater potential for cost reduction than the learning curve does. 相似文献
25.
Deepak K. Sinha 《Journal of Economics》1997,66(1):1-22
When all products in the economy are weak gross substitutes, preferences are homothetic, and firms face menu costs then all prices in an industry move together at the same rate. In the closed-loop Nash noncooperative equilibrium, all firms invest in productivity and reduce real prices. As a result, in the case of quadratic menu costs, the outputs of industries and the economy go up along S-shaped time paths characteristic of diffusion of innovations. 相似文献
26.
Toshihiko Mukoyama 《Journal of Economic Growth》2004,9(4):451-479
This article presents a model of innovation and diffusion of machines which embody a new technology. Users of the machines are heterogenous in their skill level. Skilled machine-users adopt new machines first, while unskilled users wait until machines become more user-friendly and reliable. The improvement of machines is the engine of diffusion, and it is carried out by the monopolist machine producer. The speed of diffusion is affected by the skill distribution in the economy. At any point in time, the machine producer can innovate a new generation of machines. The timing of innovation is also influenced by the skill distribution. 相似文献
27.
论GIS在社会经济领域中的运用 总被引:2,自引:0,他引:2
曾庆伟 《中南财经政法大学学报》2005,(3):23-27
地理信息系统是一种新兴的技术工具,它不仅被应用在现代测绘、军事国防、野外数据采集等自然科学方面,而且被广泛应用在社会经济领域中,在管理和决策中具有重要的作用.随着人类获取空间数据能力的不断提高和信息技术的发展,地理信息系统的应用将提升到一个新的深度和广度,它将在国民经济信息化中发挥重要的作用.本文介绍地理信息系统的基本概念及其在经济、管理、法律等领域中的应用实例,着重强调在社会经济领域中开展地理信息系统应用研究的意义. 相似文献
28.
The study analyses the determinants of international telephone, telex, telegram and leased lines communication between the United States and 46 countries. It focusses on the role of multinational firms, international trading firms and new information technologies within the framework of the theory of transaction costs.Results of the econometric estimates suggest that: (a) technological conditions of telecommunication infrastructure, i.e., international diffusion lags of new information technologies, play an important role in the explanation of international telephone and telex telecommunication flows but not in the demand for telegraph and leased lines, (b) multinational firms use international telecommunication to reduce the coordination costs and are strong customers of leased lines and telephones, but less so of telex and telegrams, (c) international trading firms exhibit less clear preferences in the use of the different media to reduce transaction costs. 相似文献
29.
Rick J. Parent Tiffany Noël Hib Rebecca A. Silver Carrie Jenkins Margaret P. Poe R. Jacob Mullins 《Technological Forecasting and Social Change》2005,72(4):171-411
Two experiments examined the effects of iterated polling and feedback on prediction accuracy for volatile world events using the Delphi paradigm. In both experiments, participants predicted rapidly changing geopolitical events. The first experiment occurred during the litigation surrounding the Clinton/Lewinsky affair in 1998. Results indicated that feedback improved individual and group accuracy for predictions of whether an event would occur. These types of predictions derived from group consensus were approximately 90% accurate, which was significantly higher than the average individual participant's accuracy. Neither polling nor feedback had much effect on time course predictions. The second experiment occurred during the American military action against the Taliban regime in Afghanistan in 2001. In Experiment 2, participants were polled three times to determine if increasing the number of iterated polls would improve Delphi accuracy. The results showed that accuracy improved from the first to the second poll but not from the second to the third. The groups predicted whether these scenarios would occur with approximately 75% accuracy, which was significantly higher than the accuracy of any individual participant. Once again, the Delphi procedure did not enhance time course predictions in Experiment 2. 相似文献
30.
技术创新扩散环境的BP神经网络评价模型研究 总被引:1,自引:0,他引:1
构建了技术创新扩散的环境评价指标体系,设计了BP神经网络评价模型,并将二者结合,运用实例验证了该模型的有效性,从而为技术创新扩散环境的评价提供借鉴。 相似文献