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排序方式: 共有3409条查询结果,搜索用时 364 毫秒
131.
We derive an elementary formula for Janossy densities for determinantal point processes with a finite rank projection-type kernel. In particular, for =2 polynomial ensembles of random matrices we show that the Janossy densities on an interval I can be expressed in terms of the Christoffel–Darboux kernel for the orthogonal polynomials on the complement of I. 相似文献
132.
基于Zernike多项式表示色域边界的色域映射 总被引:6,自引:1,他引:5
在彩色图像的跨媒体复制中,由于不同媒体有不同的色域,所以在大多数情况下色域映射是不可避免的。不论采用何种映射算法,色域映射的第一步是确定有关媒体的色域边界。目前大多数的色域边界都是用一组测量的或用其它方法得到的离散数据来表示的。然而,由于这种表示方式是利用一组离散数据来实施色域映射的两个基本处理(即确定任一指定的等色调面平面中色域的边缘线以及确定色域边界与一条映射线的交点),比较复杂和费时,因此希望找到一种色域边界的解析表达式来解决这一问题。简述了不久前提出的一种解析函数色域边界表示方法,并用实例说明了如何利用这种解析表示(Zernike多项式)来实现上述的边缘线确定和交点确定。最后给出了几种映射算法的色域映射完整过程及其结果。 相似文献
133.
讨论了圆形面偶极层静电势问题的正确解法,阐明了对于延拓法的正确理解,给出了有限间距时圆形平行板(分别带有异性面电荷)的静电势问题。 相似文献
134.
David Masson 《Designs, Codes and Cryptography》2003,28(3):283-302
We study (generalized) designs supported by words of given composition. We characterize them in terms of orthogonality relations with Specht modules; we define some zonal functions for the symmetric group and we give a closed formula for them, indexed on ordered pair of semi-standard generalized tableaux: Hahn polynomials are a particular case. We derive an algorithm to test if a set is a design. We use it to search designs in some ternary self-dual codes. 相似文献
135.
Let $\{P_n(x) \}_{n=0}^\infty$ be an orthogonal polynomial system
relative to a compactly supported measure. We find
characterizations for $\{P_n(x) \}_{n=0}^\infty$ to be a
Bochner--Krall orthogonal polynomial system, that is, $\{P_n(x)
\}_{n=0}^\infty$ are polynomial eigenfunctions of a linear
differential operator of finite order. In particular, we show that
$\{P_n(x) \}_{n=0}^\infty$ must be generalized Jacobi polynomials
which are orthogonal relative to a Jacobi weight plus two point
masses. 相似文献
136.
Let μ be a finite positive Borel measure supported in [−1,1] and introduce the discrete Sobolev-type inner productwhere the mass points ak belong to [−1,1], Mk,i0, i=0,…,Nk−1, and Mk,Nk>0. In this paper, we study the asymptotics of the Sobolev orthogonal polynomials by comparison with the orthogonal polynomials with respect to the measure μ and we prove that they have the same asymptotic behaviour. We also study the pointwise convergence of the Fourier series associated to this inner product provided that μ is the Jacobi measure. We generalize the work done by F. Marcellán and W. Van Assche where they studied the asymptotics for only one mass point in [−1,1]. The same problem with a finite number of mass points off [−1,1] was solved by G. López, F. Marcellán and W. Van Assche in a more general setting: they consider the constants Mk,i to be complex numbers. As regards the Fourier series, we continue the results achieved by F. Marcellán, B. Osilenker and I.A. Rocha for the Jacobi measure and mass points in
. 相似文献
137.
A (u1,
u2, . . . )-parking function of length
n is a sequence (x1,
x2, . . . ,
xn)
whose order
statistics (the sequence (x(1),
x(2), . . . ,
x(n)) obtained by rearranging the original sequence in
non-decreasing order) satisfy
x(i)
u(i).
The Gonarov polynomials g
n
(x; a0, a
1, . . . , a
n-1) are
polynomials biorthogonal to the linear functionals (a
i)
Di,
where (a) is evaluation at
a and D
is differentiation. In this paper, we give explicit formulas for the first and second moments of
sums of u-parking functions using Gonarov polynomials by
solving a linear recursion based on a decomposition of the set of sequences of positive integers.
We also give a combinatorial proof of one of the formulas for the expected sum. We specialize
these formulas to the classical case when u
i=a+
(i-1)b and obtain, by
transformations with Abel identities, different but equivalent
formulas for expected sums. These formulas are used to verify the classical case of the
conjecture that the expected sums are increasing functions of the gaps
ui+1
- ui.
Finally, we give analogues of our results for real-valued parking functions.AMS Subject Classification: 05A15, 05A19, 05A20, 05E35. 相似文献
138.
We investigate Fuglede's spectral set conjecture in the special case when the set in question is a union of finitely many unit intervals in dimension 1. In this case, the conjecture can be reformulated as a statement about multiplicative properties of roots of associated with the set polynomials with (0,1) coefficients. Let be an N-term polynomial. We say that {θ1,θ2,…,θN−1} is an N-spectrum for A(x) if the θj are all distinct and
139.
Franciszek Hugon Szafraniec 《Numerical Algorithms》2003,33(1-4):475-483
We discuss a possibility of deciding whether measures representing a moment sequence or realizing orthogonality of polynomials have atoms. This is done on the real line and in several variables. 相似文献
140.
Zinoviy Grinshpun 《Proceedings of the American Mathematical Society》2003,131(5):1591-1600
We prove the following theorem. Any isometric operator , that acts from the Hilbert space with nonnegative weight to the Hilbert space with nonnegative weight , allows for the integral representation
where the kernels and satisfy certain conditions that are necessary and sufficient for these kernels to generate the corresponding isometric operators.
where the kernels and satisfy certain conditions that are necessary and sufficient for these kernels to generate the corresponding isometric operators.