共查询到20条相似文献,搜索用时 15 毫秒
2.
Zulkifly Abbas S. Vahdati M. Tavassoli Kajani K.A. Atan 《Applied mathematics and computation》2009,210(2):473-478
In this paper, the properties of the floor function has been used to find a function which is one on the interval [0, 1) and is zero elsewhere. The suitable dilation and translation parameters lead us to get similar function corresponding to the interval [a,b). These functions and their combinations enable us to represent the stepwise functions as a function of floor function. We have applied this method on Haar wavelet, Sine–Cosine wavelet, Block-Pulse functions and Hybrid Fourier Block-Pulse functions to get the new representations of these functions. 相似文献
3.
S. S. Volosivets 《Mathematical Notes》1997,62(3):306-313
In this paper the best polynomial approximation in terms of the system of Faber-Schauder functions in the spaceC
p
[0, 1] is studied. The constant in the estimate of Jackson’s inequality for the best approximation in the metric ofC
p
[0, 1] and the estimate of the modulus of continuity ω1−1/p
are refined.
Translated fromMatematicheskie Zametki, Vol. 62, No. 3, pp. 363–371, September, 1997.
Translated by N. K. Kulman 相似文献
4.
We define a new notion of ``HP-small' set which implies that is both -porous and Haar null in the sense of Christensen. We show that the set of all continuous functions on which have finite unilateral approximate derivative at a point is HP-small, as well as its projections onto hyperplanes. As a corollary, the same is true for the set of all Besicovitch functions. Also, the set of continuous functions on which are Hölder at a point is HP-small.
5.
Jonas Kubilius 《Acta Appl Math》1999,58(1-3):175-188
The paper presents an overview of main methods and results of the value distribution problem of additive arithmetical functions. 相似文献
6.
This paper presents a numerical method for solving nonlinear optimal control problems including state and control inequality constraints. The method is based upon rationalized Haar functions. The differential and integral expressions which arise in the system dynamics, the performance index and the boundary conditions are converted into some algebraic equations which can be solved for the unknown coefficients. Illustrative examples are included to demonstrate the validity and applicability of the technique. 相似文献
7.
Conditions for a system of contractions and translations of a function to be a Riesz basis are given. 相似文献
8.
M.A. Navascués 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(12):4152-4165
The Haar system is an alternative to the classical Fourier bases, being particularly useful for the approximation of discontinuities. The article tackles the construction of a set of fractal functions close to the Haar set. The new system holds the property of constitution of bases of the Lebesgue spaces of p-integrable functions on compact intervals. Likewise, the associated fractal series of a continuous function is uniformly convergent. The case p=2 owns some peculiarities and is studied separately. 相似文献
9.
10.
Mohamed Vall Ould Moustapha 《偏微分方程(英文版)》2015,28(1):9-22
The Cauchy problemfor the wave equation with bi-inverse square potential on Euclidean plane is solved in terms of the two variables Appell F2 hypergeometric functions. Our principal tools are the Hankel transforms and the special functions of mathematical physics. 相似文献
11.
设=2 N,一实值函数μ:→[0,1]称为统计测度.如果若A,B∈,A∩B=,则μ(A∪B)=μ(A)+μ(B)且μ(k)=0.本文得到了统计测度的表示定理及统计测度在概率空间的应用. 相似文献
12.
Let hR denote an L∞ normalized Haar function adapted to a dyadic rectangle R⊂d[0,1]. We show that for choices of coefficients α(R), we have the following lower bound on the L∞ norms of the sums of such functions, where the sum is over rectangles of a fixed volume:
13.
HICKERNELL Fred J 《中国科学A辑(英文版)》2009,52(11):2309-2320
This article considers universal optimality of digital nets and lattice designs in a regression model. Based on the equivalence theorem for matrix means and majorization theory,the necessary and sufficient conditions for lattice designs being φp-and universally optimal in trigonometric function and Chebyshev polynomial regression models are obtained. It is shown that digital nets are universally optimal for both complete and incomplete Walsh function regression models under some specified conditions,and are... 相似文献
14.
J. Michael Wilson 《Proceedings of the American Mathematical Society》1997,125(3):755-762
For , define , where is a tensor product of one-parameter Haar functions. Let and . We prove a sufficient condition, which is close to necessary, on double sequences of weights and non-negative , which ensures that the inequality
holds for all . We extend our result to an inequality concerning two-parameter wavelet families.
15.
Let G be a locally compact group with a fixed right Haar measure andX a separable Banach space. LetL
p
(G, X) be the space of X-valued measurable functions whose norm-functions are in the usualL
p
. A left multiplier ofL
p
(G, X) is a bounded linear operator onB
p
(G, X) which commutes with all left translations. We use the characterization of isometries ofL
p
(G, X) onto itself to characterize the isometric, invertible, left multipliers ofL
p
(G, X) for 1 ≤p ∞,p ≠ 2, under the assumption thatX is not thel
p
-direct sum of two non-zero subspaces. In fact we prove that ifT is an isometric left multiplier ofL
p
(G, X) onto itself then there existsa y ∃ G and an isometryU ofX onto itself such thatTf(x) = U
(R
y
f)(x). As an application, we determine the isometric left multipliers of L1 ∩L
p
(G, X) and L1 ∩C
0
(G, X) whereG is non-compact andX is not the lp-direct sum of two non-zero subspaces. If G is a locally compact abelian group andH is a separable Hubert space, we define
where г is the dual group of G. We characterize the isometric, invertible, left multipliers ofA
p
(G, H), provided G is non-compact. Finally, we use the characterization of isometries ofC(G, X) for G compact to determine the isometric left multipliers ofC(G, X) providedX
*
is strictly convex. 相似文献
16.
Chun‐Hui Hsiao 《Numerical Methods for Partial Differential Equations》2014,30(2):536-549
This article presents a rational Haar wavelet operational method for solving the inverse Laplace transform problem and improves inherent errors from irrational Haar wavelet. The approach is thus straightforward, rather simple and suitable for computer programming. We define that P is the operational matrix for integration of the orthogonal Haar wavelet. Simultaneously, simplify the formulae of listing table (Chen et al., Journal of The Franklin Institute 303 (1977), 267–284) to a minimum expression and obtain the optimal operation speed. The local property of Haar wavelet is fully applied to shorten the calculation process in the task. The operational method presented in this article owns the advantages of simpler computation as well as broad application. We still can obtain satisfying solution even under large matrix. Moreover, we do not have numerically unstable problems. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 536–549, 2014 相似文献
17.
18.
Chaoying Zhou Lihua Yang Yingjun Liu Zhihua Yang 《Journal of Computational and Applied Mathematics》2009
In this paper, an algorithm for computing the Hilbert transform based on the Haar multiresolution approximation is proposed and the L2-error is estimated. Experimental results show that it outperforms the library function ‘hilbert’ in Matlab (The MathWorks, Inc. 1994–2007). Finally it is applied to compute the instantaneous phase of signals approximately and is compared with three existing methods. 相似文献
19.
Sergey V. Astashkin Pavel A. Terekhin 《Journal of Mathematical Analysis and Applications》2018,457(1):645-671
Let be a mean zero function and let , , be the dyadic dilations and translations of f. We investigate conditions on f, under which the linear operator defined by , , where , , are mean zero Haar functions, can be continuously extended to the closed linear span in a certain function space X. Among other results we prove that is bounded in every symmetric space with nontrivial Boyd indices whenever and f has “good” Haar spectral properties. In the special case of so-called Haar chaoses the above results can be essentially refined and sharpened. In particular, we find necessary and sufficient conditions, under which the operator , generated by a Haar chaos f of order 1, is continuously invertible in for all . 相似文献
20.
In this work, we present a computational method for solving nonlinear Fredholm integral equations of the second kind which is based on the use of Haar wavelets. Error analysis is worked out that shows efficiency of the method. Finally, we also give some numerical examples. 相似文献