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32.
A matrix rational Lanczos method for model reduction in large‐scale first‐ and second‐order dynamical systems 下载免费PDF全文
In the present paper, we describe an adaptive modified rational global Lanczos algorithm for model‐order reduction problems using multipoint moment matching‐based methods. The major problem of these methods is the selection of some interpolation points. We first propose a modified rational global Lanczos process and then we derive Lanczos‐like equations for the global case. Next, we propose adaptive techniques for choosing the interpolation points. Second‐order dynamical systems are also considered in this paper, and the adaptive modified rational global Lanczos algorithm is applied to an equivalent state space model. Finally, some numerical examples will be given. 相似文献
33.
María Fernanda Manrique-de-la-Cuba Luis Leyva-Parra Diego Inostroza Prof. Badhin Gomez Dr. Alejandro Vásquez-Espinal Prof. Jorge Garza Dr. Osvaldo Yañez Prof. William Tiznado 《Chemphyschem》2021,22(10):906-910
We report the global minima structures of Li8Si8, Li10Si9, and Li12Si10 systems, in which silicon moieties maintain structural and chemical bonding characteristics similar to those of their building blocks: the aromatic clusters Td−Li4Si4 and C2v−Li6Si5. Electron counting rules, chemical bonding analysis, and magnetic response properties verify the silicon unit‘s aromaticity persistence. This study demonstrates the feasibility of assembling silicon-based nanostructures from aromatics clusters as building blocks. 相似文献
34.
The triply bonded heavier main-group compounds have a textbook trans-bent geometry, in contrast to a familiar linear form found for the lightest analogues. Strikingly, the unexpected linear group 13 E≡E triple bonds were herein found in the D4h-symmetry E2Li62+ clusters, and they possess a large barrier (>18.0 kcal/mol) towards the dissociation of Li+. The perfectly surrounded Li4 motifs and two linear coordinated Li atoms strongly suppress the increasing nonbonded electron density of heavier E atoms, making two degenerate π bonds and one multi-center σ bond in linear heavier main-group triple bonds. The surrounding Li6 motifs not only creates an effective electronic structure to form a linear E≡E triple bond, but the resulting electrostatic interactions account for the highly stable global E2Li62+ clusters. 相似文献
35.
In this paper, we consider the three dimensional Cauchy problem of the compressible micropolar viscous flows. We prove the existence of unique global classical solution for smooth initial data with small initial energy but possibly large oscillations and the initial density may allowed to contain the interior and far field vacuum states. Furthermore, the large time behavior of the solution is obtained as well. 相似文献
36.
The phenomenon of the chaotic boundary crisis and the related concept of the chaotic destroyer saddle has become recently a new problem in the studies of the destruction of chaotic attractors in nonlinear oscillators. As it is known, in the case of regular boundary crisis, the homoclinic bifurcation of the destroyer saddle defines the parameters of the annihilation of the chaotic attractor. In contrast, at the chaotic boundary crisis, the outset of the destroyer saddle which branches away from the chaotic attractor is tangled prior to the crisis. In our paper, the main point of interest is the problem of a relation, if any, between the homoclinic tangling of the destroyer saddle and the other properties of the system which may accompany the chaotic as well as the regular boundary crisis. In particular, the question if the phenomena of fractal basin boundary, indeterminate outcome, and a period of the destroyer saddle, are directly implied by the structure of the destroyer saddle invariant manifolds, is examined for some examples of the boundary crisis that occur in the mathematical models of the twin-well and the single-well potential nonlinear oscillators. 相似文献
37.
参数激励与强迫激励联合作用下非线性振动系统的余维2退化分叉 总被引:4,自引:0,他引:4
在本文里我们首先研究了具有Z_2-对称性的范式理论和退化向量场的普适开折理论。然后利用上述理论研究了参数激励与强迫激励联合作用下非线性振动系统的余维2退化分叉,从而解决了当解具有两个零特征值时解的稳定性问题。最后利用Melnikov方法求出了参数平面上的同宿分叉曲线,讨论了全局分叉的存在性。 相似文献
38.
多传感器融合技术在低成本车辆组合导航定位系统中的应用 总被引:3,自引:0,他引:3
采用多传感器信息融合技术,运用位置/航向的输出校正和元件参数误差的补偿校正的方法,利用一阶马尔可夫模型建立了传感器参数的误差模型,提出了基于集中卡尔曼滤波的GPS/INU车辆组合导航算法。仿真结果表明上述方法是行之有效的。 相似文献
39.
本文应用Normal Form理论和退化向量场的普适开折理论研究了参数激励与强迫激励联合作用下非线性振动系统的余维2退化分叉,用Melnikov方法讨论了全局分叉的存在性. 相似文献
40.
计算具有区间参数结构的固有频率的优化方法 总被引:7,自引:0,他引:7
基于区间函数的单向包含性质,把具有区间非确定参数结构的固有频率所在区间范围问题
转化成两个全局优化问题,并采用一种实数编码遗传算法求取问题的全局解. 用一种能够求
得剪切型结构和弹簧质量系统特征值范围精确解的单调分析方法进行检验. 在一
些文献中,直接采用区间数运算法则和有限元法得到结构区间刚度阵和区间质量阵,并把关
于该区间刚度阵和区间质量阵的广义区间特征值问题的特征值区间作为待求的非确定性结构
的特征值所在的区间范围,该方法易于扩大问题的解域. 算例表明,可望得到结构
固有频率区间范围的准确解. 相似文献