散斑面内形变场检测系统设计

数字散斑测量是一种非接触、全场测量的高精度光测方法。该系统由散斑生成装置、数据采集装置和数据处理装置三部分组成。散斑生成装置将扩散的激光束投射到待测物体上,用接收屏接收物体散射生成的散斑图像。数据采集装置主要由CCD和数字采集卡组成,CCD拍摄散斑图像,并将其传输给数字采集卡,经采集卡转换成数字图像,以矩阵形式输入到数据处理装置。数据处理装置根据光学相关识别技术设计的检测程序对采集到的数字图像进行相关运算,通过对相关峰的准确定位来获取物体的形变信息。     

Partial Flocks of Non-Singular Quadrics in PG(2r + 1, q)

We generalise the definition and many properties of partial flocks of non-singular quadrics in PG(3, q) to partial flocks of non-singular quadrics in PG(2r + 1, q).     

Influence of nonlinear perturbed terms on the oscillation of elliptic equations

Our concern is to solve the nonlinear perturbation problem for the semilinear elliptic equation in an exterior domain of with . The lower limit of the nonlinear perturbed term is given for all nontrivial solutions to be oscillatory. The tools for obtaining our theorems are the so-called ``supersolution-subsolution' method and some results concerning the oscillation and nonoscillation of solutions of the ordinary differential equation associated with the elliptic equation. A simple example is given to illustrate the main results.

     

Convergence of cascade algorithm for individual initial function and arbitrary refinement masks

The cascade algorithm plays an important role in computer graphics and wavelet analysis. For any initial function φn, a cascade sequence (φn)n∞=1 constructed by the iteration φn=Cnφn-1=1,2.. where Cαis defined by g∈Lp(R) In this paper, we characterize the convergence of a cascade sequence in terms of a sequence of functions and in terms of joint spectral radius. As a consequence, it is proved that any convergent cascade sequence has a convergence rate of geometry, i.e., ||φ 1-φn||Lp(R)=O((？)n)for some (？)∈(0.1i). The condition of sum rules for the mask is not required. Finally, an example is presented to illustrate our theory.     

Parametric Bäcklund transformations I: Phenomenology

We begin an exploration of parametric Bäcklund transformations for hyperbolic Monge-Ampère systems. (The appearance of an arbitrary parameter in the transformation is a feature of several well-known completely integrable PDEs.) We compute invariants for such transformations and explore the behavior of four examples, two of which are new, in terms of their invariants, symmetries, and conservation laws. We prove some preliminary results and indicate directions for further research.

     

Modeling the mechanical behavior of metal-reinforced plastic pipes under internal pressure

Numerical nonlinear models for the mechanical behavior of the metal-reinforced plastic pipes (MRP) in destructive tests are developed to analyze the stress-strain state (SSS) in such pipes during loading. The influence of contact conditions at the polyethylene-steel boundary on the SSS of the metal-reinforced plastic pipes at normal temperatures is considered. A criterion of ultimate state of MRP is suggested to predict the load-carrying capacity of the pipes under internal pressure. The behavior of a welded butt joint of the MRP is studied, a stress redistribution phenomenon in the reinforcing skeleton is revealed, and the results obtained in destructive tests of butt joints are explained.Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 1, pp. 57–70, January–February, 2005.     

Norms Concerning Subdivision Sequences and Their Applications in Wavelets

Let a:=(a(α))_{α ^s} be a finitely supported sequence of r×r matrices and M be a dilation matrix. The subdivision sequence {(a_n(α))_{α ^s}:n } is defined by a₁=a and

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Let 1≤p≤∞ and f=(f¹,…,f^r)^T be a vector of compactly supported functions in L_p( ^s). The stability is not assumed for f. The purpose of this paper is to give a formula for the asymptotic behavior of the L_p-norms of the combinations of the shifts of f with the subdivision sequence coefficients: Such an asymptotic behavior plays an essential role in the investigation of wavelets and subdivision schemes. In this paper we show some applications in the convergence of cascade algorithms, construction of inhomogeneous multiresolution analyzes, and smoothness analysis of refinable functions. Some examples are provided to illustrate the method.     

预应力空心管桩挤土对围护结构的影响

通过施工实施和位移实测结果，分析预应力空心管桩挤土对围护结构位移和土压力的影响，提出了土压力分析方法，反演了地基水平抗力系数的比例常数m值。     

Rates of uniform convergence of extreme order statistics

Summary Bounds for the convergence uniformly over all Borel sets of the largest order statistic as well as of the joint distribution of extremes are established which reveal in which way these rates are determined by the distance of the underlying density from the density of the corresponding generalized Pareto distribution. The results are highlighted by several examples among which there is a bound for the rate at which the joint distribution of thek largest order statistics from a normal distribution converges uniformly to its limit.     

Laryngeal pathological findings following trauma to cricoarytenoid joint

Abnormal vocal cord mobility may result from trauma to the cricoarytenoid joint. A rabbit model of this kind of trauma was established in order to investigate pathological changes of the traumatized joint. Two types of pathological changes in the cricoarytenoid joint (acute inflammatory reaction in the early stage and fibrosis in the later stage) were noted. The above phenomena might be the mechanism of vocal cord dysfunction caused by trauma to the cricoarytenoid joint. The recovery of vocal cord function may depend on whether or not there is fibrosis of the cricoarytenoid joint. It is almost impossible to regain normal vocal cord function as soon as fibrosis of the joint occurs. Therefore, it is important to treat the patients effectively and immediately in the early stage of trauma for recovery.