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61.
In this paper, we present a new algorithm to estimate a regression function in a fixed design regression model, by piecewise
(standard and trigonometric) polynomials computed with an automatic choice of the knots of the subdivision and of the degrees
of the polynomials on each sub-interval. First we give the theoretical background underlying the method: the theoretical performances
of our penalized least-squares estimator are based on non-asymptotic evaluations of a mean-square type risk. Then we explain
how the algorithm is built and possibly accelerated (to face the case when the number of observations is great), how the penalty
term is chosen and why it contains some constants requiring an empirical calibration. Lastly, a comparison with some well-known
or recent wavelet methods is made: this brings out that our algorithm behaves in a very competitive way in term of denoising
and of compression. 相似文献
62.
Non-compact generalized variational inequalities for quasi-monotone and hemi-continuous operators with applications 总被引:1,自引:0,他引:1
Some results are obtained for non-compact cases in topological vector spaces for the existence problem of solutions for some
set-valued variational inequalities with quasi-monotone and lower hemi-continuous operators, and with quasi-semi-monotone
and upper hemi-continuous operators. Some applications are given in non-reflexive Banach spaces for these existence problems
of solutions and for perturbation problems for these set-valued variational inequalities with quasi-monotone and quasi-semi-monotone
operators.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
63.
64.
Kung-Yu Chen 《Journal of Mathematical Analysis and Applications》2004,298(2):411-417
In his recent investigations involving differential operators for some generalizations of the classical Laguerre polynomials, H. Bavinck [J. Phys. A Math. Gen. 29 (1996) L277-L279] encountered and proved a certain summation identity for the classical Laguerre polynomials. The main object of this sequel to Bavinck's work is to prove a generalization of this summation identity for the Srivastava-Singhal polynomials. The demonstration, which is presented here in the general case, differs markedly from the earlier proof given for the known special case. It is also indicated how the general summation identity can be applied to derive the corresponding result for one class of the Konhauser biorthogonal polynomials. 相似文献
65.
Y.Charles Li 《Journal of Mathematical Analysis and Applications》2004,292(1):311-315
Isospectral problem of both 2D and 3D Euler equations of inviscid fluids, is investigated. Connections with the Clay problem are described. Spectral theorem of the Lax pair is studied. 相似文献
66.
无界区域R1上推广的B-BBM方程的整体吸引子 总被引:4,自引:0,他引:4
本文研究了无界区域R^1上推广的B—BBM方程的长时间动力学行为,证明了该方程整体吸引子的存在性. 相似文献
67.
Shy-Der Lin 《Journal of Mathematical Analysis and Applications》2004,294(2):399-411
The main object of this paper is to investigate several general families of hypergeometric polynomials and their associated single-, double-, and triple-integral representations. Some known or new consequences of the general results presented here, involving such classical orthogonal polynomials as the Jacobi, Laguerre, Hermite, and Bessel polynomials, and various other relatively less familiar hypergeometric polynomials, are also considered. Each of the integral representations, which are derived in this paper, may be viewed also as a linearization relationship for the product of two different members of the associated family of hypergeometric polynomials. 相似文献
68.
A flow model in combination with a statistical-dynamical turbulence generator and a linearised Euler time-domain model for sound waves were used to simulate the effect of screen-induced turbulence on the noise level in the acoustical shadow of a screen in wind. Instead of simulating a great number of different frozen turbulence realisations, the concept of transient turbulence was successfully tested and applied. This concept is adequate to the time-domain model and reduces the computational demands. Several two-dimensional simulations allowed to isolate the individual effects of wind and screen on the propagation of 500 Hz sound waves over a 4-m high noise barrier. At a distance of 250 m from the source (240 m behind the screen) the sheltering effect of the screen and the refraction effect of the wind are in the order of 6 and 4 dB, respectively. The screen-induced turbulence leads to fluctuations in the noise level with a standard deviation of 1.2 dB and a maximum amplitude of 3 dB. However, the time averaged effect turned out to be in the order of merely 0.2 dB. The effect of the screen-induced turbulence on the average noise level behind the screen is therefore negligible. 相似文献
69.
利用集值映射不动点定理及最优化问题与变分不等式的关系给出线性G^↑ateaux可微的锥凸映射的广义有效点的一个存在性定理。 相似文献
70.
关于一个数论函数的导数及应用 总被引:1,自引:0,他引:1
Kanemitsu教授给出了欧拉求和函数的推广公式Lu(x,a)=0n相似文献