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1.
广义Frame与广义Frame的商   总被引:2,自引:2,他引:0  
刘菡  贺伟 《数学学报》2007,50(5):1031-104
本文将frame、frame同态、商frame与核的概念在范畴意义下作推广,并且证明Frame范畴是广义Frame范畴的反射子范畴.进而讨论了一个广义frame A的商与A上核函子之间的关系.特别地,我们证明了A上全部核函子所构成的范畴N(A)是一个广义frame.  相似文献   

2.
双边Prequantale中的Frame核映射   总被引:1,自引:1,他引:0  
In this paper, a Frame nucleus and prime elements in a Prequantale are defined. The concrete structure of a Frame prequantic quotient is considered, and the relation between the half-prime element and the Frame nucleus in a two-side Prequantale are obtained.  相似文献   

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王学强  王顺钦 《数学季刊》2006,21(3):402-405
Prequantale quotient is defined in terms of prequantic nucleus, some equivalent propositions of which is obtained. Also, prequantale quotient is proved to coincide with the quotient object in PQuant up to isomorphism. At last, the concrete structure of the largest spatial frame quotient in TPQuant is given.  相似文献   

5.
首先,在并半格中引入了上覆盖关系的概念,并以此为基础引入强并半格以及强并半格中上覆盖和C-滤子的概念,证明了强并半格S中全体C-滤子之族C Fil(S)是余Frame,讨论了简单上集值映射u:S→C Fil(S)的相关并半格同态性质;其次,证明了由一族余Frame{A_λ|λ∈Γ}的直积Π_(λ∈Γ)A_λ中只有有限个坐标非零的元素构成的子集A是强并半格,还证明了A是余Frame族{A_λ|λ∈Γ}在并半格范畴中的余积对象;最后,通过各个坐标集中的上覆盖关系在A中定义了上覆盖C~*,再结合简单上集值映射u:A→C~*Fil(A)和标准入射qλ:Aλ→Π_(λ∈Γ)A_λ(λ∈Γ),证明了强并半格A中由上覆盖C~*诱导的余Frame C~*Fil(A)是余Frame族{A_λ|λ∈Γ}在余Frame范畴中的余积对象.  相似文献   

6.
We present approximations of a large class of Weyl–Heisenberg frame operators on \(L^{2}({\mathbb {R}})\) by Gabor Bessel sequence operators generated by compactly supported smooth functions.  相似文献   

7.
Basic facts for Gabor frame {Eu(m)bTu(n)ag}m,n∈p on local field are investigated. Accurately, that the canonical dual of frame {Eu(m)bTu(n)ag}m,n∈p also has the Gabor structure is showed; that the product ab decides whether it is possible for {Eu(m)bTu(n)ag}m,n∈p to be a frame for L2(K) is discussed; some necessary conditions and two sufficient conditions of Gabor frame for L2(K) are established. An example is finally given.  相似文献   

8.
Pointwise convergence and uniform convergence for wavelet frame series is a new topic. With the help of band-limited dual wavelet frames, this topic is first researched.  相似文献   

9.
In 2000, Papadakis announced that any orthonormal wavelet must be derived by a generalized frame MRA (GFMRA). In this paper, we give a characterization of GFMRAs which can derive orthonormal wavelets, and show a general approach to the constructions of non-MRA wavelets. Finally we present two examples to illustrate the theory.  相似文献   

10.
刘群锋 《计算数学》2011,33(3):249-256
基于非单调的frame概念,提出了一个求解无约束最优化问题的直接搜索共轭梯度算法.该算法不使用充分下降条件而能够在网格(grid)之外进行搜索,这一点不同于GSS(generating setsearch)算法框架,后者为了实现网格之外的搜索必须使用充分下降条件或者移动网格(movinggrids)技术或者有理点阵(r...  相似文献   

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本文对余Frame范畴(以余Frame为对象,以余Frame同态为态射)中的等化子和余等化子的结构进行了研究。首先,利用子余Frame和嵌入映射构造了两个态射(具有相同论域和相同余论域)的等化子;其次,利用商余Frame和典型映射构造了两个态射(具有相同论域和相同余论域)的余等化子。本文的结果是对余Frame研究工作的补充和完善。  相似文献   

14.
Parseval Frame Wavelet Multipliers in L2(Rd)   总被引:1,自引:0,他引:1  
Let A be a d × d real expansive matrix. An A-dilation Parseval frame wavelet is a function ?? ?? L 2(? d ), such that the set $ \left\{ {\left| {\det A} \right|^{\frac{n} {2}} \psi \left( {A^n t - \ell } \right):n \in \mathbb{Z},\ell \in \mathbb{Z}^d } \right\} $ forms a Parseval frame for L 2(? d ). A measurable function f is called an A-dilation Parseval frame wavelet multiplier if the inverse Fourier transform of d??? is an A-dilation Parseval frame wavelet whenever ?? is an A-dilation Parseval frame wavelet, where ??? denotes the Fourier transform of ??. In this paper, the authors completely characterize all A-dilation Parseval frame wavelet multipliers for any integral expansive matrix A with |det(A)| = 2. As an application, the path-connectivity of the set of all A-dilation Parseval frame wavelets with a frame MRA in L 2(? d ) is discussed.  相似文献   

15.
Frame Wavelets with Compact Supports for L^2(R^n)   总被引:1,自引:0,他引:1  
The construction of frame wavelets with compact supports is a meaningful problem in wavelet analysis. In particular, it is a hard work to construct the frame wavelets with explicit analytic forms. For a given n × n real expansive matrix A, the frame-sets with respect to A are a family of sets in R^n. Based on the frame-sets, a class of high-dimensional frame wavelets with analytic forms are constructed, which can be non-bandlimited, or even compactly supported. As an application, the construction is illustrated by several examples, in which some new frame wavelets with compact supports are constructed. Moreover, since the main result of this paper is about general dilation matrices, in the examples we present a family of frame wavelets associated with some non-integer dilation matrices that is meaningful in computational geometry.  相似文献   

16.
在分配格中引入了次极大滤子的概念,并以此给出了分配格的滤子格是空间式frame的一种新证明,然后研究了次极大滤子在Heyting代数中的一些具体性质。  相似文献   

17.
In this paper we study the fusion frame potential that is a generalization of the Benedetto-Fickus (vectorial) frame potential to the finite-dimensional fusion frame setting. We study the structure of local and global minimizers of this potential, when restricted to suitable sets of fusion frames. These minimizers are related to tight fusion frames as in the classical vector frame case. Still, tight fusion frames are not as frequent as tight frames; indeed we show that there are choices of parameters involved in fusion frames for which no tight fusion frame can exist. We exhibit necessary and sufficient conditions for the existence of tight fusion frames with prescribed parameters, involving the so-called Horn-Klyachko’s compatibility inequalities. The second part of the work is devoted to the study of the minimization of the fusion frame potential on a fixed sequence of subspaces, with a varying sequence of weights. We related this problem to the index of the Hadamard product by positive matrices and use it to give different characterizations of these minima.  相似文献   

18.
A new class of alternative dual frames is introduced in the setting of finite frames for ℝ d . These dual frames, called Sobolev duals, provide a high precision linear reconstruction procedure for Sigma-Delta (ΣΔ) quantization of finite frames. The main result is summarized as follows: reconstruction with Sobolev duals enables stable rth order Sigma-Delta schemes to achieve deterministic approximation error of order O(N-r)\mathcal{O}(N^{-r}) for a wide class of finite frames of size N. This asymptotic order is generally not achievable with canonical dual frames. Moreover, Sobolev dual reconstruction leads to minimal mean squared error under the classical white noise assumption.  相似文献   

19.
W irst Introduce the concept oftrames.Definition We call txne(2,2)alsebr洲;+;·)a w。e If B Is elldowed with an uPP。rsc。lllattlce order‘”<”“satlsfyingthe Nil。  相似文献   

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