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91.
本文讨论了广义中心阶乘数的性质,刻画了广义中心阶乘数与高阶Euler-Bernoulli数和多项式的关系,建立了一些包含 Norlund Euler-Bernoulli多项式恒等式,推广了 Dilcher K.[1],Zhang Wenpeng[2]和 Zeitlin David[3]的结果. 相似文献
92.
Sami Omar. 《Mathematics of Computation》2001,70(236):1607-1616
Using Weil's explicit formula, we propose a method to compute low zeros of the Dedekind zeta function. As an application of this method, we compute the first zero of the Dedekind zeta function associated to totally complex fields of degree less than or equal to 30 having the smallest known discriminant.
93.
1. Introduction and NotationsThe generalized Feller operators which include many famous operators, such ajsBernstein, Szasz-Mirakjan, BaskakoV, Meyer--K5nig and Zeller operators, can be constructed by making use of the probabilistic method. In the paper [1][2], Xu JihuaPr(--lvjdetl a general scheme f(,r its construction, and Zhao Jillghui showed that theFeller type operators are of good approximations f'or unbounded functions.Our purpose is to present representation of moment generating … 相似文献
94.
We consider the heat equation with a superlinear absorption term in and study the existence of nonnegative solutions with an m-dimensional time-dependent singular set, where . We prove that if , then there are two types of singular solutions. Moreover, we show the uniqueness of the solutions and specify the exact behavior of the solutions near the singular set. 相似文献
95.
96.
97.
高阶亚线性Duffing方程的周期解 总被引:1,自引:0,他引:1
在本文中,二阶亚线性Duffing方程周期解存在的结果被推广到高阶Duffing方:x^(2n)+g(x)=p(t)=p(t+2π)(n≥1)和x^(2n+1)+g(x)-p(t)=p(t+2π)。 相似文献
98.
Insulating lines and channels prepared by focused ion beam implantation on SIMOX wafers have been investigated by thermally modulated optical reflectance microscopy using optical and electrical excitation. Continuous hot lines and hot spots can be visualized by modulated electrical heating, whereas insulating lines forming channels can be imaged only with simultaneous optical and electrical excitation. Three different schemes have been investigated for the combined excitation: (i) optical modulation with additional DC voltage, (ii) optical and electrical pumps modulated at the same frequency with the detection effected at higher harmonics and (iii) two different modulation frequencies used for optical and electrical excitation with the detection effected at sum and difference frequencies. When detecting at higher frequencies, best contrast for the observation of the insulating lines adjacent to a channel is achieved by recording the modulated reflectance signal at the fourth harmonic 4f where f is the modulation frequency of the optical and electrical pump. The observed contrast enhancement of the double excited thermoreflectance signal is found to be mainly of a thermal origin. 相似文献
99.
Liana L. Dawson 《Journal of Differential Equations》2007,236(1):199-236
In this paper we study unique continuation properties of solutions to higher (fifth) order nonlinear dispersive models. The aim is to show that if the difference of two solutions of the equations, u1−u2, decays sufficiently fast at infinity at two different times, then u1≡u2. 相似文献
100.
The authors consider a higher order multi-point boundary value problem. Some existence and nonexistence results for positive solutions of the problem are obtained by using Krasnosel'skii's fixed point theorem. Examples are included to illustrate the results. 相似文献