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81.
Learning by doing,spillovers and shakeouts   总被引:1,自引:0,他引:1  
This paper studies industry evolution driven by non strategic learning by doing and spillovers. We characterize a dynamic process of cost and output changes and its effect on welfare and industry profits. The paper gives conditions for shakeouts to occur and analyzes the key factors affecting these conditions. Since shakeouts could lead to a long-run social loss due to higher market concentration, there is a role for a government to play in limiting unnecessary shakeouts. The most effective way to do so is to enhance spillovers.JEL Classification: L11, L13, O31Correspondence to: Michael TroegeWe would like to thank Hans Mewis, Christophe Moussu and an anonymous referee for valuable comments and suggestions. We also benefited from comments of seminar participants at WZB, Humboldt University, Northwestern University and the EEA/ESEM 1999 meetings. Part of the research was carried out while Michael Tröge was visiting Northwestern University. Financial support by the German Research Council (DFG) is gratefully acknowledged.  相似文献   
82.
Transitioning towards a sustainable energy system requires the large-scale introduction of novel energy demand and supply technologies. Such novel technologies are often expensive at the point of their market introduction but eventually become cheaper due to technological learning. In order to quantify potentials for price and cost decline, the experience curve approach has been extensively applied to renewable and non-renewable energy supply technologies. However, its application to energy demand technologies is far less frequent. Here, we provide the first comprehensive review of experience curve analyses for energy demand technologies. We find a widespread trend towards declining prices and costs at an average learning rate of 18 ± 9%. This finding is consistent with the results for energy supply technologies and for manufacturing in general. Learning rates for individual energy demand technologies are symmetrically distributed around the arithmetic mean of the data sample. Absolute variation of learning rates within individual technology clusters of 7 ± 4%-points and between technology clusters of 7 ± 5%-points both contribute to the overall variability of learning rates. Our results show that technological learning is as important for energy demand technologies as it is for energy supply technologies. Applying the experience curve approach to forecast technology costs involves, however, unresolved uncertainties, as we demonstrate in a case study for the micro-cogeneration technology.  相似文献   
83.
In this paper, an adaptive algorithm is designed for dynamic risk management in petroleum project investment based on a variable precision rough set (VPRS) model. In risk management, at each stage of decision-making, experts are invited to identify risk indices and support the decision-maker in evaluating the risk exposure (RE) of individual projects. The VPRS model is used to mine risk rules and determine the significance of risk indices from RE decision tables. Considering that there are multiple risks involved in any petroleum project investment, we use multi-objective programming to obtain the optimal selection of projects with minimum RE, where the significance of risk indices is assigned to each of the corresponding multi-objective functions as a weight. Moreover, we develop a risk ranking model to measure the degree of risk for individual projects in a portfolio. Finally, a numerical example based on a Chinese petroleum company's investments in overseas projects is presented to illustrate the proposed approach, and then conclusions are drawn.  相似文献   
84.
Science and technology for renewable and sustainable energy are indispensable for our future society and economics. To meet the goal of sustainable energy development, there is a growing body of research efforts world wide. The planner of energy research has to grasp the broader coverage of scientific and technological research, and make decisions on effective investment in promising and emerging technologies especially under circumstances of limited resources. In this paper, we track emerging research domains in energy research by using citation network analysis. Our analysis confirms that the fuel cell and solar cell are rapidly growing domains in energy research. We further investigate the detailed structure of these two domains by clustering publications in these domains. Each citation cluster has characteristic research topics, and there is a variety of growth trends among the clusters. By using citation network analysis, we can track emerging research domains among a pile of publications efficiently and effectively.  相似文献   
85.
This article analyses the potential diversification benefits available to high-net-worth investors utilizing multiple portfolio managers. We show that enlisting seven actively managed portfolios from multiple portfolio managers generate significant benefits in terms of risk reduction, and, interestingly, diversification benefits are shown to be larger for low-risk portfolios compared to high-risk portfolios.  相似文献   
86.
Abstract.  Credit risk is the most important type of risk in terms of monetary value. Another key risk measure is market risk, which is concerned with stocks and bonds, and related financial derivatives, as well as exchange rates and interest rates. This paper is concerned with market risk management and monitoring under the Basel II Accord, and presents Ten Commandments for optimizing value-at-risk (VaR) and daily capital charges, based on choosing wisely from (1) conditional, stochastic and realized volatility; (2) symmetry, asymmetry and leverage; (3) dynamic correlations and dynamic covariances; (4) single index and portfolio models; (5) parametric, semi-parametric and non-parametric models; (6) estimation, simulation and calibration of parameters; (7) assumptions, regularity conditions and statistical properties; (8) accuracy in calculating moments and forecasts; (9) optimizing threshold violations and economic benefits; and (10) optimizing private and public benefits of risk management. For practical purposes, it is found that the Basel II Accord would seem to encourage excessive risk taking at the expense of providing accurate measures and forecasts of risk and VaR.  相似文献   
87.
Links between the reputation of organizations and their financial performance are intuitively attractive to assume, but often difficult to demonstrate convincingly. Gaps between employee and customer perceptions of corporate reputation have traditionally been associated with poor performance. In the context of service business and applying assimilation‐contrast theory, we hypothesize that the nature of such gaps will, in reality, have a differential effect on future revenue depending on the size and valence of the gap. The effects of small gaps should be assimilated by customers, but larger ones have a greater potential of creating a contrast effect resulting in significant increases or decreases in subsequent sales. In businesses where employees have a more positive view of the company reputation than customers, we hypothesize a growth in future sales, and where they have a relatively more negative view, a decline. We test the effects of what we label as reputation gaps in 56 business units drawn from nine service organizations and confirm our hypotheses. Among the implications of our findings are that managing reputation by elevating employee perceptions of a company's reputation above those perceived by its customers holds the potential to enhance future sales. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
88.
金融危机席卷而来。2009年,麦肯锡咨询公司特别采访了多家大公司的14名领导人,请他们反思自己觉得从危机中学到了什么。当然,这次访谈也不想把他们的评论仅仅局限于当前的衰退,还请他们思考了在以前扭亏为盈的转型或危机期间曾经面临的挑战。  相似文献   
89.
新创企业初创阶段的战略导向对其未来存续具有持久影响,但具体影响机理有待论证。采用STROBE六维划分法,连续4年对D&B数据库中的抽样企业进行调研与“健康检查”,基于523家美国新创企业数据, 剖析6种初创战略导向对新创企业存活率的差异化影响机理。结果表明:竞争企图性战略持续消耗组织资源从而增加失败风险;分析性战略提升组织决策质量从而降低失败风险;防御性战略使组织积极运用科学管理方法与技术工具从而增加生存机会;前瞻性战略对新创企业存续没有显著影响;先动性战略推动组织创新从而开拓更佳发展前景;风险承担性战略使组织不断学习、广泛探索、保持领先,最大幅度地提高新创企业存活机率。  相似文献   
90.
A quarter-century after reunification, labor productivity in the states of eastern Germany continues to lag systematically behind the West. Persistent gaps in total factor productivity (TFP) are the proximate cause; conventional and capital-free measurements confirm a sharp slowdown in TFP growth after 1995. Strikingly, eastern capital intensity, especially in industry, exceeds values in the West, casting doubt on the embodied technology hypothesis. TFP growth is negatively associated with rates of investment expenditures. The stubborn East-West TFP gap is best explained by low concentration of managers, low startup intensity and the distribution of firm size in the East rather than R&D activities.  相似文献   
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