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91.
On the Bergman space of the unit ball of Cn, we study the finite rank problem for Toeplitz products with harmonic symbols. We first solve the problem with two factors in case symbols have local continuous extension property up to the boundary. Also, in case symbols have additional Lipschitz continuity up to (some part of) the boundary, we solve the problem for multiple products with number of factors depending on the dimension n. Analogous theorems on the polydisk are also obtained.  相似文献   
92.
Some integral relations for orthogonal polynomials are elucidated. We review the generic scheme of the star-product construction and study in detail the star-product scheme based on the tomographic map. The dual star-product operator symbols are also considered and studied. Some integral kernels related to the star-product are calculated and new integral formulas for special functions are derived.  相似文献   
93.

When does a continuous map have chaotic dynamics in a set ? More specifically, when does it factor over a shift on symbols? This paper is an attempt to clarify some of the issues when there is no hyperbolicity assumed. We find that the key is to define a ``crossing number' for that set . If that number is and 1$">, then contains a compact invariant set which factors over a shift on symbols.

  相似文献   

94.
The concept of discrete statistical Abel convergence is introduced. In terms of Berezin symbols we present necessary and sufficient condition under which a series with bounded sequence {an}n?0 of complex numbers is discrete statistically Abel convergent. By using concept of statistical convergence we also give slight strengthening of a result of Gokhberg and Krein on compact operators.  相似文献   
95.
A CHARACTERIZATION OF N-DIMENSIONAL DAUBECHIES TYPE TENSOR PRODUCT WAVELET   总被引:2,自引:0,他引:2  
1. IntroductionSince the iniroduction by Daubechiesl1l of compactly supported orthogonal waveletbases in R with arbitrary high smoothness, various new wavelet bases have been constructedand aPplied successfully in image processing, numerical computation, statistics, etc. Manyof these applications, such as image compression, empIoy wavelet bases in R2. Virtuallyall of these bases are separable, that is, the bivariate functions are simply tensor productsof univariate basis functions. A separab…  相似文献   
96.
本文研究二次数域 F= 的 K2OF结构,其中 d-3 mod 9和 d ≠-3.找到了关于F=的K2OF的3阶元和F=的K2OF的生成元,推广T Bass和 Tate的一个定理和给出了 F= 的 K2OF的结构以及 SLn(OF)(n≥3)的表示关系.  相似文献   
97.
We treat the Dirac operator on the Fuzzy sphere with the help of the generalized coherent state. It is shown that the derivatives can be constructed by Moyal product with symbol of the operator. We obtain the eigenvalue of the free fermion Dirac operator as same as the result by [Hajime Aoki, Satoshi Iso, and Kelichi Nagao, Phys. Rev.D67 (2003) 065018]. Meanwhile, we also give the eigenvalue of Dirac operator with U(1) Dirac monopole background.  相似文献   
98.
The Pearson IV function was used to fit the asymmetric solid-state 27Al NMR spectra of alumina based catalysts. A high convergence (correlation coefficient is no less than 0.997) between experimental and simulated spectra was achieved. The decomposition of the 27Al NMR spectra of zinc/aluminum mixed oxides with different Zn/Al molar ratio revealed an increased fraction (6–9%) of pentacoordinated aluminum atoms in these oxides as compared to γ-Al2O3. As the Zn/Al ratio is raised, the fraction of [AlO6] octahedral units decreases, while the fraction of [AlO4] tetrahedra increases.  相似文献   
99.
M-ary and code shift keying(CSK)spread spectrum is generally applied to overcoming the spreading gain versus data rate limitation in underwater acoustic(UWA)communications.In addition,the concept of orthogonal M-ary CSK is introduced to UWA communication to gain higher rates.We propose a scheme employing dual-orthogonal-channel M-ary and CSK spread spectrum UWA communication based on Gold sequences owing large code set and good self and cross correlation.The modulation and demodulation scheme of the orthogonal M-ary CSK is derived algebraically and the factors critical to its performance are discussed.Furthermore,its bit error rate(BER)curve is evaluated via simulations and compared with the dual-channel M-ary CSK.Finally,the validity of the simulations is verified in tank experiments.1096.8 bps data rate of the proposed communication scheme is realized for 10 kbits data volume with no error.Overall through deduction,numerical simulation,and experiment,it is shown that the proposed method offers significantly improved performance.  相似文献   
100.
We obtain all positive integer solutions(m1,m2,a,b)with ab,gcd(a,b)=1 to the system of Diophantine equations km21-lat1bt2a2r=C1,km22-lat1bt2b2r=C2,with C1,C2∈{-1,1,-2,2,-4,4},and k,l,t1,t2,r∈Z such that k0,l0,r0,t10,t2 0,gcd(k,l)=1,and k is square-free.  相似文献   
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