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1.
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   
2.
论文介绍6片不同高宽比的水泥聚苯模壳格构式混凝土墙体在轴压力和水平往复侧推力作用下的试验,分析这种墙体的抗侧强度、刚度和延性等力学性能.试验表明,高宽比大于1的墙体破坏时表现为墙体跟部的单一水平裂缝,其他部位完好;高宽比3∶4的墙体破坏时存在多条通过格构梁柱的斜向裂缝,墙体裂缝分布密集,变形能力好.  相似文献   
3.
4.
In this article, we will investigate the properties of iterative sequence for non-expansive mappings and present several strong and weak convergence results of successive approximations to fixed points of non-expansive mappings in uniformly convex Banach spaces. The results presented in this article generalize and improve various ones concerned with constructive techniques for the fixed points of non-expansive mappings.  相似文献   
5.
The anion-exchange properties of a new organomineral sorbent obtained by modification of clinoptilolite-containing tuffs by polyhexamethyleneguanidine have been studied after different periods of storage (time after synthesis) and numbers of sorption-regeneration cycles. The sorbent can be used as a cation- and an anion-exchanger simultaneously. Selectivity coefficients (exchange constants) for F, SO4 2–, and HPO4 2– ionsvs. Cl ions on modified clinoptilolite-containing tuffs have been determined. The modification improves the mechanical properties of clinoptilolite tuffs.For part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1554–1556, September, 1994.  相似文献   
6.
Let E be a real reflexive Banach space having a weakly continuous duality mapping Jφ with a gauge function φ, and let K be a nonempty closed convex subset of E. Suppose that T is a non‐expansive mapping from K into itself such that F (T) ≠ ??. For an arbitrary initial value x0K and fixed anchor uK, define iteratively a sequence {xn } as follows: xn +1 = αn u + βn xn + γn Txn , n ≥ 0, where {αn }, {βn }, {γn } ? (0, 1) satisfies αn +βn + γn = 1, (C 1) limn →∞ αn = 0, (C 2) ∑n =1 αn = ∞ and (B) 0 < lim infn →∞ βn ≤ lim supn →∞ βn < 1. We prove that {xn } converges strongly to Pu as n → ∞, where P is the unique sunny non‐expansive retraction of K onto F (T). We also prove that the same conclusions still hold in a uniformly convex Banach space with a uniformly Gâteaux differentiable norm or in a uniformly smooth Banach space. Our results extend and improve the corresponding ones by C. E. Chidume and C. O. Chidume [Iterative approximation of fixed points of non‐expansive mappings, J. Math. Anal. Appl. 318 , 288–295 (2006)], and develop and complement Theorem 1 of T. H. Kim and H. K. Xu [Strong convergence of modified Mann iterations, Nonlinear Anal. 61 , 51–60 (2005)]. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
7.
Focused on the sensitivity to climate change and the special mechanical characteristics of undisturbed expansive soil, an elastc-plastic damage constitutive model was proposed based on the mechanics of unsaturated soil and the mechanics of damage. Undisturbed expansive soil was considered as a compound of non-damaged part and damaged part. The behavior of the non-damaged part was described using non-linear constitutive model of unsaturated soil. The property of the damaged part was described using a damage evolution equation and two yield surfaces, i.e., loading yield (LY) and shear yield (SY). Furthermore, a consolidation model for unsaturated undisturbed expansive soil was established and a FEM program named UESEPDC was designed. Numerical analysis on solid-liquid-gas tri-phases and multi-field couple problem was conducted for four stages and fields of stress, displacement, pore water pressure, pore air pressure, water content, suction, and the damage region as well as plastic region in an expansive soil slope were obtained.  相似文献   
8.
We introduce the notion of almost expansive sequences and curves and study their ergodic and asymptotic properties in a Hilbert space H. We apply our results to study the asymptotic behavior of solutions to the quasi-autonomous expansive type evolution system (du/dt)(t) + f(t) ∈ Au(t) on [0, ∞).  相似文献   
9.
膨胀土判别与分类的Bayes判别分析法   总被引:1,自引:0,他引:1  
基于Bayes判别分析法以建立膨胀土判别与胀缩等级分类的Bayes判别分析模型. 模型选用液限,胀缩总率,塑性指数,天然含水率,自由膨胀率等5个指标作为判别因子;将膨胀土的胀缩性分为极强、强、中、弱4个等级并作为Bayes判别分析的4个正态总体;以训练样本建立Bayes线性判别函数,以该函数计算待判样品的Bayes判别函数值,以最大值对应的总体作为样品的归属;以刀切法对判别准则进行评价. 研究表明,该模型以刀切法计算的误判率为13.3%.  相似文献   
10.
广义特征坐标系计算膨胀波与激波优越性的数值验证   总被引:2,自引:2,他引:0  
陈正  石静  吴子牛 《计算物理》2004,21(1):15-20
最近提出的以流体速度和声速的线性组合为速度而运动的广义特征坐标系,是-个更为-般的坐标系统,当参数取不同特殊值的时候,就可以得到其他经典的坐标系统.这种坐标系的最大特点是,它能跟随膨胀波(当然也可以跟随激波和接触间断)运动,从而在使用同-计算格式的前提下,使得膨胀波的计算精度更高.对膨胀波和激波进行数值试验,结果显示广义特征坐标系在计算膨胀波和激波时明显优于传统的坐标系.  相似文献   
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