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   749篇
  免费   32篇
  国内免费   9篇
财政金融   78篇
工业经济   34篇
计划管理   227篇
经济学   124篇
综合类   108篇
运输经济   2篇
旅游经济   4篇
贸易经济   92篇
农业经济   50篇
经济概况   71篇
  2023年   8篇
  2022年   9篇
  2021年   13篇
  2020年   21篇
  2019年   18篇
  2018年   12篇
  2017年   24篇
  2016年   18篇
  2015年   14篇
  2014年   38篇
  2013年   54篇
  2012年   42篇
  2011年   67篇
  2010年   62篇
  2009年   47篇
  2008年   63篇
  2007年   58篇
  2006年   49篇
  2005年   40篇
  2004年   29篇
  2003年   31篇
  2002年   12篇
  2001年   23篇
  2000年   20篇
  1999年   6篇
  1997年   4篇
  1996年   3篇
  1995年   1篇
  1989年   1篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
排序方式: 共有790条查询结果,搜索用时 62 毫秒
1.
In 2015, China and India's population represented approximately 35.74% of the total number of people living in the world. Due to the historical context and behavior of the most relevant indicators, this study proposes to utilize a wide variety of demographic, economic, and production indicators from 1952 to 2015 to assess their impact on the GNI in China and India. A comprehensive and new fangled modeling process with stepwise, regularization and distributed lag regression approaches is presented. Accordingly, theoretical results were corroborated through extensive diagnostic tests and an empirical check of the models' predictive capacity. The findings show that GNI in China is most influenced by variables such as reserves in foreign currency and the dependency ratio; whereas, variables of energy production and birth rate were generated for India. Therefore, it's the timing for China to relax the universal two-child policy. Due to the current value below the substitution rate, a gloomy outlook for China's future population and economy is predicted. Conversely, a positive outlook is forecasted for India, given the low price in the future of oil- India's primary raw material.  相似文献   
2.
Presence of excess zero in ordinal data is pervasive in areas like medical and social sciences. Unfortunately, analysis of such kind of data has so far hardly been looked into, perhaps for the reason that the underlying model that fits such data, is not a generalized linear model. Obviously some methodological developments and intensive computations are required. The current investigation is concerned with the selection of variables in such models. In many occasions where the number of predictors is quite large and some of them are not useful, the maximum likelihood approach is not the automatic choice. As, apart from the messy calculations involved, this approach fails to provide efficient estimates of the underlying parameters. The proposed penalized approach includes ?1 penalty (LASSO) and the mixture of ?1 and ?2 penalties (elastic net). We propose a coordinate descent algorithm to fit a wide class of ordinal regression models and select useful variables appearing in both the ordinal regression and the logistic regression based mixing component. A rigorous discussion on the selection of predictors has been made through a simulation study. The proposed method is illustrated by analyzing the severity of driver injury from Michigan upper peninsula road accidents.  相似文献   
3.
《The World Economy》2018,41(5):1309-1341
Has the G20 achieved its goals in macroeconomic cooperation since 2008? The paper organises the G20's efforts under five themes: macroeconomic stimulus, fiscal consolidation, monetary policy, the global financial safety net and global imbalances. The G20 was initially successful in each of these areas, but this success was short‐lived. While the G20 met its goals on macroeconomic stimulus, it has been less successful in reducing deficits and debt. While it was successful in increasing its resources, the global financial safety net remains too small, too fragmented and institutional reform is incomplete. While the G20 succeeded in moving to more market‐determined exchange rates and avoiding competitive devaluations, it struggled to avoid negative spillovers. Despite years of effort, the G20 has made limited progress in reducing global imbalances. Current account imbalances are creeping back to pre‐crisis levels. Public debt remains high and most economies are moving in the wrong direction in correcting imbalances in household savings and debt. The paper concludes that the G20 has done better in some areas than others. But to suggest the G20 is a forum in decline ignores its shift from reactive crisis response to longer‐term structural challenges outside of the pressing need of an immediate crisis.  相似文献   
4.
[目的]碳足迹及碳承载力的时空演变分析是当前分析温室气体排放量的热点问题。[方法]文章采用2004~2014年河北省化石能源消费数据、土地利用结构数据以及经济社会数据,通过构建碳足迹模型,基于Arc GIS平台对河北省11个地级市的碳足迹、碳承载力、净碳足迹进行时空演变分析。[结果](1)2004~2014年河北省碳足迹由2.224 5亿t增长至4.792 2亿t,其中煤炭能源消费量占90%左右,唐山、邯郸和石家庄碳足迹值较高,分别占河北省碳足迹的33%、18%和16%;(2)2004~2014年河北省碳承载力由9 043万t增长至1.050 6亿t,其中林地碳承载力占河北省碳承载力的97%左右,西南地区农、林业发达,碳承载力相对较高;(3)2004~2014年河北省净碳足迹呈逐年上升趋势,由1.536 7亿t增长至4.236 5亿t,唐山、邯郸及石家庄净碳足迹较大,分别占河北省净碳足迹的40%、22%和16%;(4)除保定外,其他10个地级市的碳足迹压力指数变化强度均呈现不同程度的增强趋势。此次研究成果将为河北省未来制定温室气体排放量等相关政策的建设提供参考。[结论]整体来看,河北省碳足迹及碳承载力呈逐年增长的变化趋势,应加强温室气体的管控力度,减小碳排放给河北省带来的负面影响。  相似文献   
5.
One of the most robust stylized facts in macroeconomics is the forecasting power of the term spread for future real activity. We propose a possible causal mechanism for the forecasting power of the term spread, deriving from the balance sheet management of financial intermediaries and the “risk‐taking channel of monetary policy.” Monetary tightening leads to the flattening of the term spread, reducing net interest margin and credit supply. We provide empirical support for the risk‐taking channel.  相似文献   
6.
中西部承接产业转移缺乏显著的正向技术溢出效应,成为2000年后区际技术差距持续扩大以及近年部分地区过早去工业化的关键影响因素之一。利用2001~2017年全国30个省(市)面板数据研究证实,各地区技术水平与工业增加值在地区生产总值中的份额之间存在显著正相关性;中西部在2005~2014年承接了较大规模产业转移,而区际技术差距却持续扩大,技术溢出效应显著为负。在相对偏低的技术水平条件下,中西部地区在十余年的产业承接中主要依赖于廉价的要素成本优势,其自主创新能力、创新资源积累已不足以抵御本地消费升级、要素成本上升与国际需求疲软等负面因素的叠加影响。最终,技术差距、商品及服务净输出赤字的扩大至少加快了部分欠发达地区的去工业化。  相似文献   
7.
This article contributes to a growing body of empirical literature relating credit constraints and incomplete insurance to investment decisions. We use panel data from rural Ethiopia to investigate whether participation in a safety net program enhances fertilizer adoption. Using a difference‐in‐differences estimator and inverse propensity score weighting, we find that participation in Ethiopia's food‐for‐work (FFW) program increased fertilizer adoption in the short run, but not in the long run. Results also indicate that the intensity of fertilizer usage increased with livestock holdings for FFW‐participant households, providing some evidence that the intervention helped asset‐rich farm households more than asset‐poor households. We find no significant effects of free distribution on fertilizer adoption or intensification. Our results are consistent with the hypothesis that safety nets can be viewed as mechanisms that allow households to take on more risk to pursue higher profits. The results highlight the importance of safety net programs, their effectiveness in ensuring farmers that they will be protected against uninsured shocks, and how that assurance can translate into productivity‐enhancing behavior.  相似文献   
8.
张杰 《价值工程》2014,(35):118-119
本文介绍了松软岩层在原支护状态被破坏后重新采用注浆及锚网索联合支护维修加固技术的应用方法。  相似文献   
9.
The rise of China is challenging the international financial architecture in a number of ways. This paper highlights three that are of critical importance: the challenge of absorbing massive Chinese savings; the incorporation of China into a cohesive global financial safety net; and the organisation of China's participation in funding the demand for international investment projects. The global financial architecture needs to be reformed. But what role should China play? The paper defines the options open to China and the opportunities and barriers it will face. We argue that China can work with the established economic powers in reforming the existing architecture. At the same time, China seeks cooperation in building new institutions and organisations that fill gaps in the existing arrangements. But no matter how international financial diplomacy plays out in the near term, deep financial and economic reform at home will alone deliver China a central role in the international financial architecture. Domestic reform could also attend to some of the challenges that currently plague China's impact on the system. The success or failure of these domestic reforms will be at the crux of the strength or fragility of the international financial architecture in the years ahead.  相似文献   
10.
In some refineries, storage tanks are located at two different sites, one for low-fusion-point crude oil and the other for high one. Two pipelines are used to transport different oil types. Due to the constraints resulting from the high-fusion-point oil transportation, it is challenging to schedule such a system. This work studies the scheduling problem from a control-theoretic perspective. It proposes to use a hybrid Petri net method to model the system. It then finds the schedulability conditions by analysing the dynamic behaviour of the net model. Next, it proposes an efficient scheduling method to minimize the cost of high-fusion-point oil transportation. Finally, it gives a complex industrial case study to show its application.  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