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   6554篇
  免费   471篇
  国内免费   133篇
财政金融   880篇
工业经济   314篇
计划管理   1297篇
经济学   1486篇
综合类   940篇
运输经济   75篇
旅游经济   45篇
贸易经济   662篇
农业经济   673篇
经济概况   786篇
  2024年   15篇
  2023年   159篇
  2022年   172篇
  2021年   245篇
  2020年   263篇
  2019年   195篇
  2018年   176篇
  2017年   246篇
  2016年   232篇
  2015年   260篇
  2014年   470篇
  2013年   604篇
  2012年   531篇
  2011年   603篇
  2010年   447篇
  2009年   366篇
  2008年   410篇
  2007年   356篇
  2006年   360篇
  2005年   262篇
  2004年   146篇
  2003年   149篇
  2002年   123篇
  2001年   90篇
  2000年   57篇
  1999年   48篇
  1998年   46篇
  1997年   32篇
  1996年   27篇
  1995年   9篇
  1994年   17篇
  1993年   9篇
  1992年   6篇
  1991年   9篇
  1990年   4篇
  1989年   5篇
  1986年   3篇
  1985年   2篇
  1984年   1篇
  1983年   2篇
  1982年   1篇
排序方式: 共有7158条查询结果,搜索用时 31 毫秒
21.
High firewood consumption for heating produces high levels of pollution in cities in central and southern Chile, with serious consequences for health and quality of life. Energy efficiency measures (EEMs) have been identified as the best strategy to reduce air pollution and maximize social benefits. However, their adoption has been slow. The objective of this article is to investigate household preferences for financial incentives needed to promote private investments in EEMs in Central-Southern Chilean households and study the role of energy savings and the uncertainty about potential savings in the investment decision, with the aim of finding solutions to increase the adoption of these technologies. We use a choice experiment to explore the trade-off between the investment costs, financial instruments, energy savings, and the uncertainty about achieving the theoretical savings provided by engineering and architectural models. The results show that financial instruments play the most important role in this decision, followed by the savings achieved by the retrofit. Householders prefer to finance their investments with a mix of their personal resources and medium-term credits, trying to avoid long-term commitments. Although uncertainty was found to be a significant variable, it seems to play a small role in the investment decision.  相似文献   
22.
陈媛  王伟华  王福颖 《科技和产业》2023,23(16):154-159
选取2021年度数据,采用数据包络分析(DEA)方法对中国东部地区10个省份规模以上工业企业的研发投入绩效进行评价,并采用灰关联分析方法分析确定各项研发投入产出指标相对于DEA效率的灰色关联度。研究结果表明,80%的省份规上工业企业研发投入产出处于非DEA有效状态,存在不同程度的投入冗余或产出不足;规上工业企业发明专利申请数与研发投入产出效率的关联度最高,其次是新产品销售收入和R&D经费内部支出。  相似文献   
23.
The main purpose of these work was to identify operational efficiency drivers of international airports. In order to achieve this, a two-step quantitative-qualitative research approach was conducted. In the first step, a two-stage DEA model was used, and it was possible to identify, within a sample of the 60 biggest airports from the six Airport Council International (ACI) regions, the most efficient airports of the world: Beijing International Airport, Heathrow International Airport, Dubai International Airport, and Hartsfield-Jackson Atlanta International Airport. In the second step of the research, four airports were selected in order to search for the efficiency drivers. In this context, Heathrow International Airport was considered to be a benchmark and presented most of the identified efficiency drivers (27 of 31). Standing out were Just-in-Time (JIT) and Total Quality Management (TQM) principles and also Passenger boarding optimization, besides the presence of almost all of the most relevant efficiency drivers, according to airport managers.  相似文献   
24.
We study individually rational rules to be used to allot, among a group of agents, a perfectly divisible good that is freely available only in whole units. A rule is individually rational if, at each preference profile, each agent finds that her allotment is at least as good as any whole unit of the good. We study and characterize two individually rational and efficient families of rules, whenever agents' preferences are symmetric single-peaked on the set of possible allotments. Rules in the two families are in addition envy-free, but they differ on whether envy-freeness is considered on losses or on awards. Our main result states that (a) the family of constrained equal losses rules coincides with the class of all individually rational and efficient rules that satisfy justified envy-freeness on losses and (b) the family of constrained equal awards rules coincides with the class of all individually rational and efficient rules that satisfy envy-freeness on awards.  相似文献   
25.
26.
The use–make framework is employed to explain functional forms in production theory, including Cobb–Douglas and Leontief. Productivity and efficiency are interrelated by augmenting the framework with a linear program that determines the frontier output.  相似文献   
27.
This study examines why most derivatives markets that settle on the day following expiration choose the opening rather than the closing price as the final settlement price (FSP), whereas most markets that settle on the expiration day select an average rather than a single price as the FSP. Four exogenous changes in the Taiwan Futures Exchange settlement procedures provide an experimental basis for studying the settlement procedures’ impact on underlying assets. Greatest market efficiency is observed when the FSP is determined by a single rather than an average price and hypothesize that manipulation is prevented at the expense of market quality.  相似文献   
28.
This paper investigates the impact of international sanctions on energy efficiency by employing the panel fixed effect as well as average marginal effect from the Tobit model via data on 30 sanctioned states over the period 1996–2015 with international sanctions including unilateral, plurilateral, U.S., EU, UN, economic, and non-economic cases. Overall, we find that the imposition of unilateral sanctions leads to a 0.067% decrease in energy efficiency, but that of plurilateral sanctions positively contribute to energy efficiency in the case of the full sample of countries. Moreover, the imposition of UN sanctions has a greater decrease on energy efficiency in the target states than the 0.042% reduction of energy efficiency when the sanctionist is the U.S. For robustness, empirical results indicate that the imposition of plurilateral sanctions results in a drop of energy efficiency in Islamic countries, but an increase in non-Islamic countries, while there are also negative shocks induced by the imposition of EU sanctions on energy efficiency in Asian countries, but not for non-Asian countries. We also consider endogenous problems and dynamic specification by using indicator variables and System GMM. In summary, our empirical findings provide policy suggestions for those sanctioned countries about how to maintain energy efficiency when facing international sanctions.  相似文献   
29.
We propose a novel test to measure market efficiency while estimating the time-varying risk premiums of commodity futures, given that the prices are heteroscedastic. The risk premium is estimated using a state-space model with a Kalman filter modified for heteroscedasticity. Using 79 commodity futures traded on 16 exchanges during the period 2000–2014 and a Monte Carlo simulation, we demonstrate that the proposal produces robust results compared with conventional approaches. The global financial crisis has improved the efficiency and affected the trading volumes of commodity futures, but it has had no effect on the average or the volatility of risk premiums.  相似文献   
30.
对建筑企业进行环境行为效率评价是促进我国建筑行业健康可持续发展的重要手段。根据建筑行业特点及我国现有的企业环境信用标准,构建了建筑企业环境行为评价的投入产出指标体系,将改进的数据包络分析方法模型运用到企业环境行为效率评价领域,解决了现有企业评价研究主观性突出的问题,得出建筑企业评价分析方法。在此基础上对某代表性建筑企业2010—2017年环境行为数据进行了评价分析。分析结果表明该企业环境行为总体效率良好,但鉴于出现了奇数年和偶数年的效率波动情况,仍需提高环境行为效率。  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