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111.
Chu-Li Fu Xiang-Tuan Xiong Zhi Qian 《Journal of Mathematical Analysis and Applications》2007,331(1):472-480
In this paper a simple and convenient new regularization method for solving backward heat equation—Fourier regularization method is given. Meanwhile, some quite sharp error estimates between the approximate solution and exact solution are provided. A numerical example also shows that the method works effectively. 相似文献
112.
113.
114.
A. Y. M. Chin 《Acta Mathematica Hungarica》2004,102(4):337-342
Let R be an associative ring with unit and let N(R) denote the set of nilpotent elements of R. R is said to be stronglyπ-regular if for each x∈R, there exist a positive integer n and an element y∈R such that x
n=x
n
+1
y and xy=yx. R is said to be periodic if for each x∈R there are integers m,n≥ 1 such that m≠n and x
m=x
n. Assume that the idempotents in R are central. It is shown in this paper that R is a strongly π-regular ring if and only if N(R) coincides with the Jacobson radical of R and R/N(R) is regular. Some similar conditions for periodic rings are also obtained.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
115.
Montgomery and Vaughan improved a theorem of Erd?s and Fuchs for an arbitrary sequence. Sárközy extended this theorem of Erd?s and Fuchs for two arbitrary sequences which are "near" in a certain sense. Using the idea of Jurkat (differentiation of the generating function), we will extend similarly the result of Montgomery and Vaughan for "sufficiently near" sequences. 相似文献
116.
Zhen‐Feng Chen Hong‐Li Zhou Hong Liang Yan Li Ren‐Gen Xiong Xiao‐Zeng You 《应用有机金属化学》2003,17(11):883-884
The centrosymmetric binuclear structure of [Pb2(H‐Norf)2(ONO2)4]shows the geometry around each lead(II) atom to be distorted trigonal bipyramidal with Pb–O distances ranging from 2.357(3) to 2.769(4) Å. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
117.
An exponentially fitted special second-order finite difference method is presented for solving singularly perturbed two-point boundary value problems with the boundary layer at one end (left or right) point. A fitting factor is introduced in a tri-diagonal finite difference scheme and is obtained from the theory of singular perturbations. Thomas Algorithm is used to solve the system and its stability is investigated. To demonstrate the applicability of the method, we have solved several linear and non-linear problems. From the results, it is observed that the present method approximates the exact solution very well. 相似文献
118.
119.
Controllability of Functional Integro-Differential Inclusions with an Unbounded Delay 总被引:1,自引:0,他引:1
In this paper, a sufficient condition is established for the controllability of neutral functional integro-differential inclusions
with an unbounded delay in Banach spaces. The approach used is a fixed-point theorem for condensing maps due to Martelli and
the theory of analytic semigroup of linear operators.
Communicated by F. Zirilli
Research supported by NNSF of China, by the Teaching and Research Award Program for Outstanding Young Teachers in Higher Education
Institutions of the Ministry of Education of China, and by the Qing Lan Talent Engineering Fund QL-05-164 of Lanzhou Jiaotong
University. The authors are grateful to Professor F. Zirilli and two anonymous referees for valuable suggestions improving
this paper. 相似文献
120.