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51.
In this paper we introduce a nonlinear version of the notion of Anzellotti's pairing between divergence-measure vector fields and functions of bounded variation, motivated by possible applications to evolutionary quasilinear problems. As a consequence of our analysis, we prove a generalized Gauss–Green formula. 相似文献
52.
We consider the question whether, given a countable family of lattices in a locally compact abelian group G, there exist functions such that the resulting generalized shift-invariant system is a tight frame of . This paper develops a new approach to the study of generalized shift-invariant system via almost periodic functions, based on a novel unconditional convergence property. From this theory, we derive characterizing relations for tight and dual frame generators, we introduce the system bandwidth as a measure of the total bandwidth a generalized shift-invariant system can carry, and we show that the so-called Calderón sum is uniformly bounded from below for generalized shift-invariant frames. Without the unconditional convergence property, we show, counter intuitively, that even orthonormal bases can have arbitrary small system bandwidth. Our results show that the question of existence of frame generators for a general lattice system is rather subtle and depends on analytical and algebraic properties of the lattice system. 相似文献
53.
设(Xni:1≤i≤n,n≥1)为行间ND阵列,g(x)是R^+上指数为α的正则变化函数,{αni:1≤i≤n,n≥1}为满足条件max1≤i≤n|ani|=0((g(n))^-1)的实数阵列.本文采用截尾的方法,得到了使ND随机变量阵列加权乘积和完全收敛的条件,并推广了以前学者的结论. 相似文献
54.
55.
We continue our study on arithmetical Fourier series by considering two Fourier series which are related to Diophantine analysis. The first one was studied by Hardy and Littlewood in connection with the classification of numbers and the second one was studied by Hartman and Wintner by Lebesgue integration theory. 相似文献
56.
A symbolic algorithm based on the generalized Lucas polynomials of first kind is used in order to compute the Newton sum rules for the zeros of polynomial eigenfunctions of linear differential operators with polynomial coefficients. 相似文献
57.
We study trigonometric sums in finite fields
. The Weil estimate of such sums is well known:
, where f is a polynomial with coefficients from F(Q). We construct two classes of polynomials f,
, for which
attains the largest possible value and, in particular,
. 相似文献
58.
Formulas for calculating the sum of singular series corresponding to the number of representations of integers by some quadratic forms in 12 variables with integral coefficient are derived. 相似文献
59.
E. D. Nursultanov 《Mathematical Notes》1998,63(2):205-214
In this paper we prove theorems on multiplicators of Fourier series inL
p, where the conditions depend on a parameterp. An example illustrating the importance of these conditions is constructed.
Translated fromMatematicheskie Zametki, Vol. 63, No. 2, pp. 235–247, February, 1998. 相似文献
60.
M. B. Khripunova 《Mathematical Notes》1998,63(5):658-669
The asymptotics of sums of the form Στ(|bn−a|) (summation overn<N, ω(n)=k) is studied, whereω(n) is the number of distinct prime divisors ofn, andτ(n) is the number of all divisors.
Translated fromMatematicheskie Zametki, Vol. 63, No. 5, pp. 749–762, May, 1998.
In conclusion, the author wishes to express his gratitude to Professor N. M. Timofeev for valuable advice.
This research was supported by the Russian Foundation for Basic Research under grant No. 96-01-00502. 相似文献