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Parametric Characteristic Analysis for Generalized Frequency Response Functions of Nonlinear Systems
Xing Jian Jing Zi Qiang Lang Stephen A. Billings 《Circuits, Systems, and Signal Processing》2009,28(5):699-733
In order to explicitly reveal the relationship between system frequency response functions and model parameters which define
system nonlinearities, and consequently unveil a direct connection from model parameters to system frequency response characteristics,
a parametric characteristic analysis approach is proposed for Volterra systems described by a nonlinear differential equation
(NDE). The parametric characteristics of the generalized frequency response functions (GFRFs) for the NDE model are established,
and some important properties are discussed, which can explicitly reveal what model parameters contribute and how these parameters
affect the GFRFs. Based on the parametric characteristic analysis, it is demonstrated how the system frequency domain characteristics
are related to the system time domain model parameters and how the output frequency response function can now be determined
explicitly with a detailed polynomial structure. These new results provide a significant and novel insight into the analysis
and design of nonlinear systems in the frequency domain. Several examples are included to illustrate the results. 相似文献
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Michael S. Lang 《European Journal of Combinatorics》2002,23(8):1015
Let Γ denote a bipartite distance-regular graph with diameterD ≥ 4 and valency k ≥ 3. Let θ 0 > θ 1 > > θD denote the eigenvalues of Γ and let E0, E1, , EDdenote the associated primitive idempotents. Fix s(1 ≤ s ≤ D − 1 ) and abbreviate E: = Es. We say E is a tail whenever the entrywise product E E is a linear combination of E0, E and at most one other primitive idempotent of Γ. Letqijσi + 1 h (0 ≤ h , i, j ≤ D) denote the Krein parameters of Γ and letΔ denote the undirected graph with vertices 0, 1, , D where two vertices i, j are adjacent whenever i ≠ = j andqijσi + 1s ≠ = 0. We show E is a tail if and only if one of (i)–(iii) holds: (i) Δ is a path; (ii) Δ has two connected components, each of which is a path; (iii) D = 6 and Δ has two connected components, one of which is a path on four vertices and the other of which is a clique on three vertices. 相似文献
146.
Urs Lang 《Transactions of the American Mathematical Society》1999,351(10):3975-3988
Let be metric spaces, a subset of , and a large-scale lipschitz map. It is shown that possesses a large-scale lipschitz extension (with possibly larger constants) if is a Gromov hyperbolic geodesic space or the cartesian product of finitely many such spaces. No extension exists, in general, if is an infinite-dimensional Hilbert space. A necessary and sufficient condition for the extendability of a lipschitz map is given in the case when is separable and is a proper, convex geodesic space.
147.
L. I. Korovin I. G. Lang S. T. Pavlov 《Journal of Experimental and Theoretical Physics》1999,88(1):105-113
Energy splitting ΔE res in double magnetopolaron energy spectrum in rectangular quantum wells as functions of the well width d have been calculated. We have considered in the capacity of interaction leading to resonant coupling between electrons and phonons the interaction with confined phonons and (for comparison) with bulk LO phonons. We have obtained the conditions when the interaction with bulk phonons yields correct results. Calculations for AlAs/GaAs/AlAs and AlSb/InSb/AlSb structures have been performed. Alongside the parameter ΔE res for a polaron, whose resonant magnetic field is determined by the condition Ω=ω L1, where Ω is the cyclotron frequency and ω L1 is the LO phonon frequency in the quantum well (A-polaron), we have calculated ΔE res for D-(Ω=2ω L1) and F-polarons (Ω=3ω L1), which is a factor of $\sqrt 2 $ and $\sqrt 3 $ , respectively, smaller than ΔE res for the A-polaron. Since the splitting ΔE res for the A-polaron is very large (up to 0.2?ω L1), it is more convenient to study in experiments D-and F-polarons since their resonant magnetic fields are lower. We have predicted existence of “weak” magnetopolarons, in which the splitting is proportional to a higher power of Frölich’s coupling constant α than α 1/2. 相似文献
148.
Te溶剂垂直区熔法生长Φ20MCT晶体组分控制研究 总被引:1,自引:1,他引:0
采用Te作溶剂在特制的垂直区熔炉上开展了Φ20MCT晶体的生长研究;详细阐述了该方法MCT晶体的生长过程和生长机理;总结了分析了晶体生长过程中影响组分的因素;提出了生长过程中组分控制存在的问题和改善组分控制的措施。 相似文献
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