共查询到20条相似文献,搜索用时 31 毫秒
1.
A Besov Estimate for Multilinear Singular Integrals 总被引:3,自引:0,他引:3
Wengu Chen 《数学学报(英文版)》2000,16(4):613-626
Abstract
The main purpose of this paper is to prove a good λ inequality for a multilinear singular integral in ℝ
n
.
The research is supported by Beijing Education Commission Foundation and Beijing Natural Science Foundation (Project No. 1982005) 相似文献
2.
Given a projective surface and a generic projection to the plane, the braid monodromy factorization (and thus, the braid monodromy
type) of the complement of its branch curve is one of the most important topological invariants, stable on deformations. From
this factorization, one can compute the fundamental group of the complement of the branch curve, either in ℂ2 or in ℂℙ2. In this article, we show that these groups, for the Hirzebruch surface F
1,(a,b), are almost-solvable. That is, they are an extension of a solvable group, which strengthen the conjecture on degeneratable
surfaces.
This work was supported by the Emmy Noether Institute Fellowship (by the Minerva Foundation of Germany) and Israel Science
Foundation (Grant No. 8008/02-3) 相似文献
3.
Hehu Xie 《Advances in Computational Mathematics》2008,29(2):135-145
In this paper, we use the integral-identity argument to obtain asymptotic error expansions for the mixed finite element approximation
of the Maxwell equations on a rectangular mesh. The extrapolation method is applied to improve the accuracy of the approximation
via an interpolation postprocessing technique. With the extrapolation, the approximation accuracy can be improved from O(h) to O(h
4) in the L
2-norm. Illustrative numerical results are given to demonstrate the higher order accuracy of the extrapolation method.
This research was supported by the National Natural Science Foundation of China (No.10471103), Social Science Foundation of
the Ministry of Education of China (06JA630047), Tianjin Natural Science Foundation (07JCYBJC14300). 相似文献
4.
In this paper, the matrix of equidiagonal-dominance is defined and several theorems about ‖A
−1‖∞ and its evaluation are established. Many interesting numerical examples are given.
This work is supported by the National Natural Science Foundation of China and the Science Foundation of Academy of Engineering
Physics of China 相似文献
5.
Sun Mingbao 《Journal of Geometry》2004,81(1-2):114-125
In this paper, we establish some geometric inequalities for two n-dimensional simplexes in the n-dimensional Euclidean space En.This work is supported by the Hunan Provincial Science Foundation, P. R. China. S. Mingbao is a doctorate candidate of Nanjing University of Science and Technology. 相似文献
6.
The C
1 density conjecture of Palis asserts that diffeomorphisms exhibiting either a homoclinic tangency or a heterodimensional cycle are C
1 dense in the complement of the C
1 closure of hyperbolic systems. In this paper we prove some results towards the conjecture.* Work supported by the National Natural Science Foundation and the Doctoral Education Foundation of China, and the Qiu Shi Science and Technology Foundation of Hong Kong. 相似文献
7.
Cai Di ZHAO Yong Sheng LI Sheng Fan ZHOU 《数学学报(英文版)》2007,23(11):2043-2060
This paper discusses the Cauchy problem of elliptic-elliptic-type Davey-Stewartson systems with zero-order dissipation on R^2. Making use of the Fourier spectral projector, together with a long time comparison between the solutions to the Davey-Stewartson systems and to an auxiliary problem, we prove that the global attractor in H^1 (R^2) for the addressed Davey-Stewartson systems is a compact subset of H^2(R^2), and thus reveal the asymptotic smoothing effect of the solutions for the systems. 相似文献
8.
Ming Chun XU 《数学学报(英文版)》2005,21(4):899-902
In this paper the following theorem is proved: Every group L3(q) for q = 3^(2m-1)(m≥2) is characterized by its set of element orders. 相似文献
9.
Wu Guanglei 《数学学报(英文版)》1991,7(2):97-102
In this paper the Pontrjagin forms of a closed oriented manifold immersed inR
n
are expressed in terms of Plücker coordinates.
This work is supported partially by the National Natural Science Foundation of China. 相似文献
10.
Shi Rong LI Xiu Yun GUO 《数学学报(英文版)》2007,23(4):731-734
A subgroup H of a finite group G is called a TI-subgroup if H ∩ H^x = 1 or H for all x ∈ G. In this paper, a complete classification for finite p-groups, in which all abelian subgroups are TI-subgroups, is given. 相似文献
11.
Tracial Limit of C^*-algebras 总被引:4,自引:0,他引:4
ShanWenHU HuaXinLIN YiFengXUE 《数学学报(英文版)》2003,19(3):535-556
A new limit of C^*-algebras, the tracial limit, is introduced in this paper. We show that a separable simple C^*-algebra A is a tracial limit of C^*-algebras in Z-(k) if and only if A has tracial topological rank no more than k. We present several known results using the notion of tracial limits. 相似文献
12.
The purpose of this paper is to characterize the pointwise rate of convergence for the combinations of Szász-Mirakjan operators using Ditzian-Totik modulus of smoothness. 相似文献
13.
~UNQIYU ZHENGYANZHANG 《高校应用数学学报(英文版)》1996,11(2):243-246
Abstract. In this note we construct an example of compactly supported orthonormal wavelets of non-tensor type from a multiresolutlon of 相似文献
14.
In this paper we are concerned with finite element approximations to the evaluation of American options. First, following
W. Allegretto etc., SIAM J. Numer. Anal. 39 (2001), 834–857, we introduce a novel practical approach to the discussed problem, which involves the exact reformulation
of the original problem and the implementation of the numerical solution over a very small region so that this algorithm is
very rapid and highly accurate. Secondly by means of a superapproximation and interpolation postprocessing analysis technique,
we present sharp L
2-, L
∞-norm error estimates and an H
1-norm superconvergence estimate for this finite element method. As a by-product, the global superconvergence result can be
used to generate an efficient a posteriori error estimator.
This work was supported in part by the National Natural Science Foundation of China (10471103 and 10771158), the National
Basic Research Program (2007CB814906), Social Science Foundation of the Ministry of Education of China (Numerical Methods
for Convertible Bonds, 06JA630047), Tianjin Natural Science Foundation (07JCY-BJC14300), and Tianjin University of Finance
and Economics. 相似文献
15.
GAOYI 《高校应用数学学报(英文版)》1998,13(2):150-158
Some modified Levitin-Polyak projection methods are proposed in this paper for solving monotone linear variational inequality x∈Ω,(x′-x)^T(Hx c)≤0,for any x′∈Ω.It is pointed out that there are similar methods for solving a general linear variational inequality. 相似文献
16.
Li Changpin 《应用数学学报(英文版)》2001,17(2):191-199
In this paper, we investigate the bifurcations of one class of steady-state reaction-diffusion equations of the formu″ + μu − u
k=0, subjectu(0)=u(π)=0, where μ is a parameter, 4≤kεZ
+. Using the singularity theory based on the Liapunov-Schmidt reduction, some satisfactory results are obtained.
This work is supported by the National Natural Science Foundation of China (No.19971057) and the Youth Science Foundation
of Shanghai Municipal Commission of Education (No.99QA66). 相似文献
17.
This paper investigates the asymptotic properties of the modified likelihood ratio statistic for testing homogeneity in bivariate normal mixture models with an unknown structural parameter. It is shown that the modified likelihood ratio statistic has χ22 null limiting distribution. 相似文献
18.
H. P. McKean 《Israel Journal of Mathematics》1975,21(1):54-92
The purpose of this paper is to discuss the analogy between the law of large numbers and the central limit theorem of classical
probability theory on the one hand and the hydrodynamical approximations in the statistical mechanics of gases on the other.
The chief illustration is provided by Carleman's model [2] for which the central limit approximation is a kind of non-linear
Brownian motion regulated by ∂n/∂t=(n'/n)′.
Research supported by the National Science Foundation under NSF Grant NSF-GP-37069X1. 相似文献
19.
Tim D. Cochran 《Commentarii Mathematici Helvetici》1985,60(1):291-311
A geometric notion of a “derivative” is defined for 2-component links ofS
n inS
n+2 and used to construct a sequenceβ
i
,i=1,2,... of abelian concordance invariants which vanish for boundary links. Forn>1, these generalize the only heretofore known invariant, the Sato-Levine invariant. Forn=1, these invariants are additive under any band-sum and consequently provide new information about which 1-links are concordant
to boundary links. Examples are given of concordance classes successfully distinguished by theβ
i
but not by their
, Murasugi 2-height, Sato-Levine invariant or Alexander polynomial.
Supported in part by a grant from the National Science Foundation. 相似文献
20.
In this paper we study surfaces in S4 and their twistor Gauss maps. Some necessary and sufficient conditions that the twistor Gauss map is harmonic are given. We find many examples of nonisotropic harmonic maps from a surface to P
3.Supported by the National Natural Science Foundation of China and the Science Foundation of Zhejiang Province. 相似文献