连续时间时变参数系统的指数稳定性和Lp指数稳定性

本文给出具有慢时变参数的连续时间线性齐次系统指数稳定的一个一般性条件，并给出具有随机时变参数的连续时间线性齐次系统Ｌｐ指数稳定的一个充分条件。这些结果可用来分析带有未建模动态，确定性噪声或随机噪声及慢时变参数的自适应控制系统的稳定性问题。     

关于一个Diophantus不等式的整数解个数

命t(m,q;r)=(m+r+g)~α-(m-r+q)~α—(m+r-q)~α+(m-r-q)~α,其中α(α-1)(α-2)(α-3)≠0。本文的目的是给出Diophantus不等式,满足条件的整数解数的较精确上界估计。其中。     

一类洪水预报的非线性时序模型——指数自回归模型

作为雨洪系统的输出——洪水时间序列，它包含了系统中各种变量的过去信息，同时蕴含着大量关于系统演变的规律和趋势，这样的时间序列往往是不可逆的，非性线相依的偏态序列，并且存在着广泛的频幅相依特性。在进行洪水预报时，传统法多采用线性化技术，但预报精度并不理想，因此要提高预报精度，有必要考虑洪水的非线性特性。基于此，本文用指数自回归模型进行洪水预报研究，实例分析表明该模型可提高洪水预报精度。本文的尝试工作为洪水预报提供了一种可行的模型。     

薄壁黄铜天线套管成型的试验研究

介绍了开发研制薄壁黄铜小直径天线套管的拉伸工艺及理论，并对拉伸断裂的塑性变形理论进行了分析探讨，进而对游动芯头拉伸与应用，提出工艺改进和提高管材表面质量的措施。     

预应力筋伸长值计算的分析与讨论

预应力筋伸长值计算公式在有关行业的现行《规范》及有关的书籍中已有一些计算公式可选用，但这些计算公式的计算结果之间存在一定的误差，这是一种公人本身存在的误差，有时这种误差比较大，从而使施工人员无所适从。通过对有关公式的计算结果进行分析，并加以修正，然后用修正后的公式计算其预应力筋伸长值，计算结果与精确值接近，从而解决了因伸长值校核不符合《规范》的实际问题。     

RC框架外包钢节点角钢延伸的研究

本文根据对角钢在节点核心区边缘处截断的对比试件的试验，分析了不同类型节点的破坏特点、抗剪机理以及抗剪强度；证明角钢在核心区外的延伸是保证角钢销栓力的必要条件。     

Rapid Anisotropic Diffusion Using Space-Variant Vision

Many computer and robot vision applications require multi-scale image analysis. Classically, this has been accomplished through the use of a linear scale-space, which is constructed by convolution of visual input with Gaussian kernels of varying size (scale). This has been shown to be equivalent to the solution of a linear diffusion equation on an infinite domain, as the Gaussian is the Green's function of such a system (Koenderink, 1984). Recently, much work has been focused on the use of a variable conductance function resulting in anisotropic diffusion described by a nonlinear partial differential equation (PDE). The use of anisotropic diffusion with a conductance coefficient which is a decreasing function of the gradient magnitude has been shown to enhance edges, while decreasing some types of noise (Perona and Malik, 1987). Unfortunately, the solution of the anisotropic diffusion equation requires the numerical integration of a nonlinear PDE which is a costly process when carried out on a uniform mesh such as a typical image. In this paper we show that the complex log transformation, variants of which are universally used in mammalian retino-cortical systems, allows the nonlinear diffusion equation to be integrated at exponentially enhanced rates due to the nonuniform mesh spacing inherent in the log domain. The enhanced integration rates, coupled with the intrinsic compression of the complex log transformation, yields a speed increase of between two and three orders of magnitude, providing a means of performing rapid image enhancement using anisotropic diffusion.     

指数分布可靠性验证试验系统的设计与实现

工程实际中,大量产品采用指数分布模型。指数分布可靠性验证中,需查阅大量表格,计算分析繁琐,急需实用的计算分析软件系统。按国家军用标准提出了指数分布可靠性验证试验系统的设计与实现方法,并研制了分析软件,帮助工程技术人员快速、准确地选择验证试验方案,从而有效地评定产品质量,并使其达到预定目标。     

The Effect of the Thickness of Fe2 Al5 Phase Layer at Fe/Al Interface on the Mechanics Behavior of Hot Dip Aluminizing Coating

Hot Dip Aluminized Coatings with different thickness were prepared on Q235 steel in aluminum solutions with different temperature for certain time. Through tensile tests and in-situ SEM observations, the effect of the coating's microstructure on the tensile strength of the samples was studied. It was disclosed at certain aluminum solution temperature,transaction layers mainly composed of Fe2 Al5 phase got thicker with time prolonging, and this changed initial crack's extending direction from parallel with to vertical with stretching direction. The change in crack direction decreased tensile strength of samples, thus made the coating easy to break. It was concluded that the existence of thick Fe2 Al5 phase layer was the basic reason for the lowering of tensile strength of the coating.     

预防预应力混凝土梁端开裂的措施

桥梁后张法预应力梁端锚下混凝土局部承受很大压应力，在工程中张拉钢绞线时会遇到锚下受压区混凝土开裂的情况。通过计算、经验进行适当地配筋以及改进张拉工艺就可以避免这种情况的发生。