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31.
In this work,the well-known problem put forward by S N Bernstein in 1930 is studied in a deep step.An operator is constructed by revising double interpolation nodes.It is proved that the operator converges to arbitrary continuous functions uniformly and the convergence order is the best.  相似文献   
32.
In this paper,we present a solution methodology to obtain exact solutions of some nonlinear evolution equation by modifying the homogeneous balance method.Based on the modified homogeneous balance method,several kinds of exact(new)solutions of the generalized KdV equation are obtained.  相似文献   
33.
34.
It is shown that an n × n matrix of continuous linear maps from a pro-C^*-algebra A to L(H), which verifies the condition of complete positivity, is of the form [V^*TijФ(·)V]^n i,where Ф is a representation of A on a Hilbert space K, V is a bounded linear operator from H to K, and j=1,[Tij]^n i,j=1 is a positive element in the C^*-algebra of all n×n matrices over the commutant of Ф(A) in L(K). This generalizes a result of C. Y.Suen in Proc. Amer. Math. Soc., 112(3), 1991, 709-712. Also, a covariant version of this construction is given.  相似文献   
35.
《数学年刊B辑(英文版)》2014,(3):I0004-I0004
Inverse problems and ill-posed problems are motivated by many applications in science and engineering, and have become an important area of applied mathematics. The mathematical analysis and numerical algorithms on this subject have broad impacts on the rapid development of engineering areas, including nondestructive tests, medical imaging, remote sensing, geophysics and so on. The main difficulties in studying the inverse problems for partial differential equations are their nonlinearity and ill-posedness. Since the 1980s, there have been many new mathematical results on the theory of inverse problems and the regularization of ill-posed problems.  相似文献   
36.
As a student of Professor Zuxiu Zheng, I am greatly honored, in the occasion of his 80th birth- day, to give a brief introduction of what I know about Professor Zheng and his long lasting contribution to mathematical education and research in China over the last few decades.  相似文献   
37.
韩诚 《工科数学》2014,(3):69-70
分析了华东师大版《数学分析》(第四版)教材中关于确界原理证明的不足之处,给出更为细致的修正证明.  相似文献   
38.
In this paper, we study Prufer wmultiplication rings (PVMRs) and give some new characterizations of PVMRs. Moreover, we show that a Marot ring R is a PVMR if and only if every w-ideal of R is complete.  相似文献   
39.
This paper deals with a kind of fourth degree systems with perturbations. By using the method of multi-parameter perturbation theory and qualitative analysis, it is proved that the system can have six limit cycles.  相似文献   
40.
Strongly irreducible submodules of modules are defined as follows: A submodule N of an Rmodule M is said to be strongly irreducible if for submodules L and K of M, the inclusion L ∩ K ∈ N implies that either L ∈ N or K ∈ N. The relationship among the families of irreducible, strongly irreducible, prime and primary submodules of an R-module M is considered, and a characterization of Noetherian modules which contain a non-prime strongly irreducible submodule is given.  相似文献   
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