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   2篇
  完全免费   2篇
  物理学   4篇
  2011年   1篇
  2010年   2篇
  2004年   1篇
排序方式: 共有4条查询结果,搜索用时 31 毫秒
1
1.
李鹤  杨周  张义民  闻邦椿 《物理学报》2011,60(7):70512-070512
根据Takens定理,研究了混沌时间序列相空间重构嵌入维数的选取问题.提出了基于径向基函数神经网络预测模型性能的嵌入维数估计方法,即根据嵌入维数与混沌时间序列预测模型性能的变化关系来确定嵌入维数.通过对几种典型混沌动力学系统的数值验证,结果表明该方法能够确定出合适的相空间重构嵌入维数. 关键词: 混沌 相空间重构 嵌入维数 预测  相似文献
2.
徐培民  闻邦椿 《中国物理》2004,13(5):618-624
A simple branch of solution on a bifurcation diagram, which begins at static bifurcation and ends at boundary crisis (or interior crisis in a periodic window), is generally a period-doubling cascade. A domain of solution in parameter space, enclosed by curves of static bifurcation and that of boundary crisis (or the interior of a periodic window), is the trace of branches of solution. A P-n branch of solution refers to the one starting from a period-n (n≥1) solution, and the corresponding domain in parameter space is named the P-n domain of solution. Because of the co-existence of attractors, there may be several branches within one interval on a bifurcation diagram, and different domains of solution may overlap each other in some areas of the parameter space. A complex phenomenon, concerned both with the co-existence of attractors and the crises of chaotic attractors, was observed in the course of constructing domains of steady state solutions of the Hénon map in parameter space by numerical methods. A narrow domain of period-m solutions firstly co-exists with (lies on) a big period-n (m≥3n) domain. Then it enters the chaotic area of the big domain and becomes period-m windows. The co-existence of attractors disappears and is called the landing phenomenon. There is an interaction between the two domains in the course of landing: the chaotic area in the big domain is enlarged, and there is a crisis step near the landing area.  相似文献
3.
赵春雨  张义民  闻邦椿 《中国物理 B》2010,19(3):30301-030301
We derive the non-dimensional coupling equation of two exciters,including inertia coupling,stiffness coupling and load coupling.The concept of general dynamic symmetry is proposed to physically explain the synchronisation of the two exciters,which stems from the load coupling that produces the torque of general dynamic symmetry to force the phase difference between the two exciters close to the angle of general dynamic symmetry.The condition of implementing synchronisation is that the torque of general dynamic symmetry is greater than the asymmetric torque of the two motors.A general Lyapunov function is constructed to derive the stability condition of synchronisation that the non-dimensional inertia coupling matrix is positive definite and all its elements are positive.Numeric results show that the structure of the vibrating system can guarantee the stability of synchronisation of the two exciters,and that the greater the distances between the installation positions of the two exciters and the mass centre of the vibrating system are,the stronger the ability of general dynamic symmetry is.  相似文献
4.
The elementary beam model is modified to include the surface effects and used to analyze the deflections of nanowires under different boundary conditions. Tile results show that compared to deflections of nanowires without consideration of surface effects, the surface effects can enlarge or reduce deflections of nanowires, and nanowire buckling occurs under certain conditions. This study might be helpful for design of nanowire-based nanoelectromechanical systems.  相似文献
1
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