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   686篇
  免费   33篇
  国内免费   4篇
电工技术   11篇
综合类   1篇
化学工业   145篇
金属工艺   12篇
机械仪表   20篇
建筑科学   12篇
矿业工程   1篇
能源动力   69篇
轻工业   36篇
水利工程   8篇
石油天然气   12篇
无线电   72篇
一般工业技术   142篇
冶金工业   35篇
原子能技术   4篇
自动化技术   143篇
  2023年   11篇
  2022年   18篇
  2021年   32篇
  2020年   20篇
  2019年   16篇
  2018年   44篇
  2017年   28篇
  2016年   39篇
  2015年   26篇
  2014年   34篇
  2013年   73篇
  2012年   46篇
  2011年   52篇
  2010年   40篇
  2009年   37篇
  2008年   32篇
  2007年   20篇
  2006年   15篇
  2005年   11篇
  2004年   19篇
  2003年   10篇
  2002年   12篇
  2001年   5篇
  2000年   3篇
  1999年   7篇
  1998年   13篇
  1997年   8篇
  1996年   4篇
  1995年   2篇
  1994年   1篇
  1993年   2篇
  1992年   2篇
  1991年   5篇
  1990年   3篇
  1989年   3篇
  1988年   1篇
  1987年   4篇
  1986年   2篇
  1984年   4篇
  1983年   3篇
  1981年   2篇
  1979年   1篇
  1976年   1篇
  1975年   2篇
  1974年   2篇
  1972年   3篇
  1970年   1篇
  1968年   1篇
  1960年   1篇
  1959年   2篇
排序方式: 共有723条查询结果,搜索用时 15 毫秒
721.
Data-based safe gain-scheduling controllers are presented for discrete-time linear parameter-varying systems (LPV) with polytopic models. First, λ $$ \lambda $$ -contractivity conditions are provided under which the safety and stability of the LPV systems are unified through Minkowski functions of the safe sets. Then, a data-based representation of the closed-loop LPV system is provided, which requires less restrictive data richness conditions than identifying the system dynamics. This sample-efficient closed-loop data-based representation is leveraged to design data-driven gain-scheduling controllers that guarantee λ $$ \lambda $$ -contractivity and, thus, invariance of the safe sets. It is also shown that the problem of designing a data-driven gain-scheduling controller for a polyhedral (ellipsoidal) safe set amounts to a linear program (a semi-definite program). The motivation behind direct learning of a safe controller is that identifying an LPV system requires satisfying the persistence of the excitation (PE) condition. It is shown in this paper, however, that directly learning a safe controller and bypassing the system identification can be achieved without satisfying the PE condition. This data-richness reduction is of vital importance, especially for LPV systems that are open-loop unstable, and collecting rich samples to satisfy the PE condition can jeopardize their safety. A simulation example is provided to show the effectiveness of the presented approach.  相似文献   
722.
The Vein-Chip recapitulates CVST Virchow's triad and enables systematic characterization of venous thrombogenesis with respect to fibrin formation and platelet aggregation. Distinct from the arterial setting, platelets universally adhere across the entire CVS Vein-Chip independent of stenotic geometry and flow disturbance. Intriguingly, fibrin propagates along with the flow direction, but exclusively deposits to the inner vessel wall. Upon inflammatory endothelial injury, fibrin deposition mirrors to the outer vessel wall, but still not in the lumen. Together, the Vein-Chip promises future applications for personalized thrombotic assessment and monitoring.  相似文献   
723.
Orbital Angular Momentum (OAM) is an intrinsic property of electromagnetic waves. Great research has been witnessed in the last decades aiming at exploiting the OAM wave property in different areas in radio and optics. One promising area of particular interest is to enhance the efficiency of the available communications spectrum. However, adopting OAM-based solutions is not priceless as these suffer from wave divergence especially when the OAM order is high. This shall limit the practical communications distance, especially in the radio regime. In this paper, we propose a cooperative OAM relaying system consisting of a source, relay, and destination. Relays help the source to transmit packets to the destination by providing an alternative connection between source and destination. This cooperative solution aims on the one hand, through best-path selection, on increasing the communications range. On the other hand, through the parallel transmission orders allowed by OAM carrying waves, the system could raise its total transmission throughput. Simulation results show that combining a cooperative relay with OAM improves the system throughput compared to using each element separately. In addition, the proposed cooperative relaying OAM outperforms the cooperative relaying non-orthogonal multiple access scheme, which is a key spectrally efficient technique used in 5G technology.  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