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91.
基于多元局部多项式方法的混沌时间序列预测   总被引:3,自引:0,他引:3       下载免费PDF全文
周永道  马洪  吕王勇  王会琦 《物理学报》2007,56(12):6809-6814
根据Takens定理,把混沌时间序列构造为一组序列对,然后用多元局部多项式方法来预测其序列.这种核估计方法可以结合局域法与全局法的优点,使得预测的精度更高.仿真结果表明,该方法非常有效.  相似文献   
92.
Ground-based solar absorption infrared spectra were recorded in the Canadian Arctic during the early spring of 2004 using a moderate-resolution Fourier transform spectrometer, the Portable Atmospheric Research Interferometric Spectrometer for the Infrared (PARIS-IR). As part of the Canadian Arctic Atmospheric Chemistry Experiment (ACE) validation campaign, the PARIS-IR instrument recorded solar absorption spectra of the atmosphere from February to March 2004 as the Sun returned to the Arctic Stratospheric Ozone Observatory (AStrO) near Eureka, Nunavut, Canada (80.05°N, 86.42°W). In this paper, we briefly outline the PARIS-IR instrument configuration and data acquisition in the high Arctic. We discuss the retrieval methodology, characterization and error analysis associated with total and partial column retrievals. We compare the PARIS-IR measurements of N2O and O3 column amounts with those from the Fourier transform spectrometer (ACE-FTS) onboard the Canadian SCISAT-1 satellite and the ozonesonde data obtained at Eureka during the validation campaign.  相似文献   
93.
The authors obtain a holomorphic Lefschetz fixed point formula for certain non-compact "hyperbolic" K(a)hler manifolds (e.g. K(a)hler hyperbolic manifolds, bounded domains of holomorphy) by using the Bergman kernel. This result generalizes the early work of Donnelly and Fefferman.  相似文献   
94.
The second part of this paper deals with the systolic implementation of the computational kernel for factorial data analysis, defined in Part I, on special-purpose hardware. The framework of the study is that a sequence of different algorithms has to be performed on a unique hardware array. This fact has led us to the design of the programmable systolic array SARDA: this is a triangular array which consists of programmable nodes with local memory and programmable orthogonal connections.  相似文献   
95.
A time-stepping procedure is established and analyzed for the problem of miscible displacement in porous medium. The fluid velocity based on mixed element method is post-processed by the convolution with Bramble-Schatz kernel. Convergence analysis shows that the property of superconvergence, originally held for the approximation of velocity, can be retained for the approximation of concentration variable. Compared with the traditional results in references, the constraint conditions between parameters in this paper are improved essentially.  相似文献   
96.
We study the near diagonal asymptotic expansion of the generalized Bergman kernel of the renormalized Bochner-Laplacian on high tensor powers of a positive line bundle over a compact symplectic manifold. We show how to compute the coefficients of the expansion by recurrence and give a closed formula for the first two of them. As a consequence, we calculate the density of states function of the Bochner-Laplacian and establish a symplectic version of the convergence of the induced Fubini-Study metric. We also discuss generalizations of the asymptotic expansion for non-compact or singular manifolds as well as their applications. Our approach is inspired by the analytic localization techniques of Bismut and Lebeau.  相似文献   
97.
An approach for solving Fredholm integral equations of the first kind is proposed for in a reproducing kernel Hilbert space (RKHS). The interest in this problem is strongly motivated by applications to actual prospecting. In many applications one is puzzled by an ill-posed problem in space C[a,b] or L2[a,b], namely, measurements of the experimental data can result in unbounded errors of solutions of the equation. In this work, the representation of solutions for Fredholm integral equations of the first kind is obtained if there are solutions and the stability of solutions is discussed in RKHS. At the same time, a conclusion is obtained that approximate solutions are also stable with respect to or L2 in RKHS. A numerical experiment shows that the method given in the work is valid.  相似文献   
98.
In this paper, the author studies a class of non-standard commutators with higher order remainders for oscillatory singular integral operators with phases more general than polynomials. For 1 〈 p 〈 ∞, the L^p-boundedness of such operators are obtained provided that their kernels belong to the spaces L^q(s^n-1) for some q 〉 1.  相似文献   
99.
We study Schur Q-polynomials evaluated on a geometric progression, or equivalently q-enumeration of marked shifted tableaux, seeking explicit formulas that remain regular at q=1. We obtain several such expressions as multiple basic hypergeometric series, and as determinants and pfaffians of continuous q-ultraspherical or continuous q-Jacobi polynomials. As special cases, we obtain simple closed formulas for staircase-type partitions.  相似文献   
100.
We introduce a class of non-commutative Heisenberg-like infinite-dimensional Lie groups based on an abstract Wiener space. The Ricci curvature tensor for these groups is computed and shown to be bounded. Brownian motion and the corresponding heat kernel measures, {νt}t>0, are also studied. We show that these heat kernel measures admit: (1) Gaussian like upper bounds, (2) Cameron-Martin type quasi-invariance results, (3) good Lp-bounds on the corresponding Radon-Nikodym derivatives, (4) integration by parts formulas, and (5) logarithmic Sobolev inequalities. The last three results heavily rely on the boundedness of the Ricci tensor.  相似文献   
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