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   312篇
  免费   10篇
财政金融   41篇
工业经济   17篇
计划管理   43篇
经济学   86篇
综合类   1篇
运输经济   1篇
旅游经济   5篇
贸易经济   100篇
农业经济   2篇
经济概况   22篇
邮电经济   4篇
  2023年   6篇
  2021年   9篇
  2020年   10篇
  2019年   14篇
  2018年   15篇
  2017年   23篇
  2016年   21篇
  2015年   16篇
  2014年   26篇
  2013年   36篇
  2012年   32篇
  2011年   24篇
  2010年   10篇
  2009年   23篇
  2008年   9篇
  2007年   6篇
  2006年   9篇
  2005年   2篇
  2004年   5篇
  2003年   8篇
  2002年   5篇
  2001年   4篇
  2000年   1篇
  1998年   2篇
  1996年   1篇
  1994年   1篇
  1992年   1篇
  1975年   1篇
  1966年   1篇
  1938年   1篇
排序方式: 共有322条查询结果,搜索用时 0 毫秒
321.
With the numbers of electric vehicles on the increase, their additional electricity demand can no longer be neglected. From a power systems’ perspective, it is the time dependent electricity consumption that matters. In particular, the peak demand is increased in the case of uncontrolled charging, imposing additional stress on the system. Unfortunately, since there is an absence of representative electric vehicle driving patterns, a quantification of such temporal charging requirements is challenging. To overcome this problem, we developed a detailed model, which maps combustion engine vehicles onto electric vehicle equivalents. The model’s main strengths are the consideration of the diversity within the vehicle fleet as well as the differentiation into the boundary cases of pure battery electric vehicles and plug-in hybrid electric vehicles. Applied to a German traffic study, load curves for these two cases were generated. In addition, the existing uncertainty in between was quantified using Monte Carlo method. We show that the peak energy demand through electric vehicles is much greater on working days than on weekend days. Moreover, we find that the distinction between pure and plug-in-hybrid electric vehicles matters, at least for the time being. Apart from the numerical results, the model is well suited to generate input for more sophisticated investigations of charging strategies within energy system simulations.  相似文献   
322.
European countries are currently exploring strategies to ensure a strong level of security of energy supply while decreasing its reliance on natural gas imports. With the strong surge in shale gas developments in the USA, similar ambitions have been the ongoing subject of inquiry in Europe. Detailed knowledge about extraction costs is a key issue in determining future shale gas investments in Europe. The paper at hand analyses the potential of European shale gas resources, highlighting their competitiveness against conventional natural gas. It examines the current volume of shale gas resources in Europe and performs a detailed cost calculation to provide an estimation of shale gas production costs. The results indicate that under current market conditions the repetition of the US shale gas boom is by all measures improbable in Europe. Furthermore, in the case that natural prices were to return to historically higher levels, only a few highly productive shale gas formations would be economically competitive.  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