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   3877篇
  免费   219篇
财政金融   520篇
工业经济   179篇
计划管理   848篇
经济学   1086篇
综合类   37篇
运输经济   81篇
旅游经济   96篇
贸易经济   854篇
农业经济   125篇
经济概况   248篇
邮电经济   22篇
  2023年   64篇
  2022年   50篇
  2021年   75篇
  2020年   114篇
  2019年   161篇
  2018年   249篇
  2017年   284篇
  2016年   241篇
  2015年   113篇
  2014年   190篇
  2013年   652篇
  2012年   178篇
  2011年   143篇
  2010年   169篇
  2009年   155篇
  2008年   142篇
  2007年   92篇
  2006年   101篇
  2005年   104篇
  2004年   69篇
  2003年   75篇
  2002年   71篇
  2001年   50篇
  2000年   55篇
  1999年   45篇
  1998年   38篇
  1997年   31篇
  1996年   30篇
  1995年   33篇
  1994年   25篇
  1993年   24篇
  1992年   24篇
  1991年   21篇
  1990年   13篇
  1989年   15篇
  1988年   11篇
  1987年   9篇
  1986年   13篇
  1985年   10篇
  1984年   18篇
  1983年   15篇
  1982年   13篇
  1981年   7篇
  1980年   10篇
  1979年   11篇
  1978年   10篇
  1977年   7篇
  1976年   10篇
  1974年   11篇
  1972年   6篇
排序方式: 共有4096条查询结果,搜索用时 125 毫秒
81.
A carbon tax is potentially a policy that can reduce CO2 emissions and mitigate climate risks, at lowest economy-wide costs. We develop a dynamic CGE model for Spain to assess the economic and environmental effects of a carbon tax, and test the double dividend (DD) hypothesis. We simulate the impact of three carbon taxes: €10, €20 and €30 per ton of CO2. For each tax, four ‘revenue recycling’ scenarios are examined: a reduction of taxes on capital, on labor, on value-added tax, and a scenario in which revenues are not recycled. We find a DD for taxes of €10/ton and lower, within five to seven years of implementation. We estimate an annual CO2 emissions reduction of around 10% with this tax. Under some circumstances, the DD can be achieved for a tax of €20/ton. In any case, recycling revenues to cut pre-existing taxes reduces costs of imposing carbon taxes.  相似文献   
82.
Quality & Quantity - The content of this article is a paper about a complex mathematical model of terrain passability which respects geographical and meteorological conditions in terrain and...  相似文献   
83.
To improve its innovation process, Philips Shaving and Beauty (S&B) designed a blueprint for its innovation process. Although it has proved to be quite effective, it has experienced a lack of efficiency, in terms of frequent cost and time overruns, in the fuzzy front end of this process. We suggest a contextual innovation management approach to set up a stage‐gate‐based innovation process platform and thus improve the efficiency in the fuzzy front end, which means that, for different contexts, stage‐gate process variants will be designed from which unnecessary activities are removed and important activities are emphasized. The design is based on the identification of relevant contextual factors to develop variations of the common innovation process within Philips S&B. We distinguished different variants of the innovation processes within Philips S&B that can increase the efficiency in the fuzzy front end. Based on interviews within and outside Philips S&B, we identified problems and potential solutions with regard to efficiency in eight recently finished innovation processes. The results indicate that the most important contextual factors are the distinction between incremental and radical innovations, and between market and technology‐based innovations. We used these factors to design three variants on the basic platform of the stage‐gate process.  相似文献   
84.
85.
Principal axis methods such as principal component analysis (PCA) and correspondence analysis (CA) are useful for identifying structures in data through interesting planar graphic displays. However, some kinds of data sets can be dealt alternatively with PCA or CA. This paper focuses on methods, such as PCA and CA, and on visual displays. Our aim is to illustrate the implications for a potential user of selecting either method, and its advantages and disadvantages, from an applied point of view. This is a matter covered broadly in textbooks and elsewhere considering theoretical arguments. Our purpose is to contribute to the comparison between these methods, over the same data set, in order to illustrate them for the practitioner. In the first part of this paper we present a novel analytical study of a binary matrix associated with a non-oriented axis-symmetric graph and show that CA outperforms standardized PCA for the reconstitution and visualization of such kind of graphs. In the second part we present a case using real data dealing with the distribution of employees in different economic sectors for the countries of the European Union, analyzed by means of standardized PCA and two-way CA, in order to see the differences between the two methods in practice.  相似文献   
86.
87.
88.
This survey examines the empirical literature on the relationship between public R&D subsidies and private R&D investment over the past five decades. The survey reveals a considerable heterogeneity of empirical results that cannot be explained fully by methodological issues. We aim to provide further explanations of the possible causes of that heterogeneity. In particular, we emphasise a set of issues that, in our view, are critical to understanding the potential effect of public R&D subsidies on private R&D spending. Special attention is paid to the dynamic aspects and composition of firm R&D, the constraints faced by the firm (such as financial constraints), and the amount and source of public subsidies. None of these issues have been investigated in depth. We formulate a set of research assumptions to guide future empirical research in this field.  相似文献   
89.
This research introduces the multi-product capacitated facility location problem with general production and building costs (MP-CFLPGC). The MP-CFLPGC extends previous problems found in the literature by including multiple products and general production and building cost functions that allow the modeling of different behaviors like economies of scale and congestion. The MP-CFLPGC is formulated as a mixed integer linear program (MILP). To evaluate the performance of the proposed formulation we analyze the results of a commercial optimizer on a set of 288 randomly generated test instances that resemble the Colombian cement industry supply chain. After one hour the optimizer achieved an optimality gap of 1.0 % or less in 55 % out of the 288 test instances. On average the optimality gap was 3.57 %. Additionally, we propose a randomized mathematical-programming-based heuristic for the test instances where the MILP formulation presents significantly high optimality gaps.  相似文献   
90.
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