结构函数

Since a proposed application of Dirac structures is to the reduction of some mechanical systems, the reduction of Dirac structures is considered in detail in this paper, without using the existence of momentum mappings or the introducing of the notion of admissible function, etc..

因为引入Dirac结构的—个基本目的即应用于一些力学系统的约化，本文详细地讨论了Dirac结构的约化问题，包括其在Poisson流形以及Jacobi流形等的约化中的重要应用，重点利用了Dirac结构的特征对以及对偶特征对的工具，从而避开了讨论矩映射的存在性以及容许函数等一些复杂概念的介入。

We give several sufficient conditions of NA and NSD properties of random variables, compare the closeness of distribution functions of order statistics between NA and independent rv's, investigate properties of NSD defined by supermodular functions, study the dependence structure of stationary Markov process and order statistics and their spacings from two samples, establish stochastic comparisons of order statistics of heterogeneous rv's in the hazard rate and the reversed hazard rate orders, and give the first analytic proof of the closure property of the up shifted likelihood ratio order under convolution.

给出判定一组随机变量NA性质的几个充分条件，并给出NA和独立随机变量的次序统计量之间"贴近性"的比较，系统地研究基于特殊函数类所定义的NSD负相依概念，给出一些判别NSD性质的结构定理和一些有用概率不等式。系统研究平稳马氏过程的相依结构。研究两样本次序统计量及其问题隔的相依结构。在失效率、反向失效率序和似然序意义下给出非齐次随机变量次序统计量的比较。给出上漂移似然序卷积封闭性的第一个解析证明。

Firstly, the author establish the functions of stability on the basis of the spline function method ,according to the theory of geometrical nonlinear and the theory of stability, educe the stability equation of structure based on variational principle, then carry through the flexuosity analysis of CFST arch.The big distortion geometrical nonlinear was considered by the stability equation,the author simplified the problem of geometrical nonlinear through ignored quadratic term and reserve the simple term, at last boiled down to solve the linear stability equation of eigenvalue .

利用样条函数方法、根据几何非线性变形理论和结构稳定性理论，先建立起结构稳定的泛函，再由变分原理导出结构的稳定方程，进行钢管混凝土拱屈曲分析；本文所建立的稳定方程考虑了几何非线性的大变形效应，通过忽略几何非线性的二次项，保留一次项，将几何非线性问题简化，最后归结为求解线性稳定问题的特征值稳定方程，建立了结构非线性静力稳定性问题的新算法及失稳类型判别准则。

The macroscopic rheological parameters and microstructure parameters were closely related, it is helpful to explain the essence of multiple rheological properties through the analysis of which the wax evolution process and microstructure of the crude oil which is waxy and high viscosity; the yield time of gelled waxy crude oil monotone increases along with the decreasing of rate of shear (the time of stress effect prolonged), there was power function relationship between them, it can be expressed with ; when adding diesel oil to Sudan crude oil, dilute proportion bigger the eccentricity degree of paraffin particles were bigger too, that was to say the symmetry of wax crystal was better, the wax crystal form fabric more hardly when the intermolecular interaction was smaller; in the light of macroscopica, the fall extent of the abnormity temperature, solidifying point and viscosity could be larger along with the accretion of dilute proportion, as a result, it's rheological properties could be improved.

SD原油析蜡点为94℃，析蜡高峰为50～30℃，异常点为40℃；其蜡晶颗粒细小、对称性差，所以具有较大的比表面能，容易形成联生、联锁结构；损耗角曲线与储能模量曲线或损耗模量曲线的交点所对应的温度与原油凝点或倾点温度非常接近，大约在39℃左右；也就是说，含蜡原油粘弹特性曲线的交点可以表征其流动性；原油宏观流变参数与微观结构参数密切相关，原油析蜡过程及蜡晶微观结构分析有助于诠释易凝高粘原油多重流变特性的本质；胶凝含蜡原油的屈服时间随剪切速率的降低而单调增加，二者显然存在幂函数关系，可用关系式描述；当SD原油加柴油稀释处理时，稀释比越高，蜡晶颗粒的偏心度也越大，亦即蜡晶对称性越好，分子间作用力越小，蜡晶颗粒越不易形成结构，宏观表现为异常点、凝点及表观粘度等流变参数下降的幅度越大，流动性越好。

Based on fuzzy feature that the concrete crack width affects concrete structure durability, the membership function that the crack width belongs to the durability failure is established, the calculation method of fuzzy probability about structure durability failure is submitted, and classifing standard of the sturucture durability state is proposed, In accordance with the stochastic nature that cracks on concrete bridges occur and grow, and by assuming that crack occurrence obeys nonstable Poission process, predicting and evaluating methods about future crack condition and durability state of concrete bridge structures are suggested.

依混凝土裂缝宽度对混凝土结构耐久性影响的模糊特性，建立了裂缝宽度隶属耐久性失效的隶属函数，提出了结构耐久性失效的模糊概率计算方法，并建议了结构耐久性状态的划分标准；针对混凝土桥梁裂缝发生、发展的随机性，以裂缝的发生服从非稳态的泊松过程的假设为前提，提出了混凝土桥梁结构裂缝未来状况及耐久性未来状态的预测评估方法。

A static interval optimization method for structures was proposed. The matrices of structures with interval parameters were given. Combining the interval extension of function with the perturbation theory of static analysis, the method for interval static analysis was derived.

提出了一种在位移约束下结构静力区间优化方法，给出了区间参数结构矩阵，将结构静力分析的摄动理论与区间函数扩张定理相结合，推导了结构静力分析的区间方法。

Therefore,a series studies of ice-pier vibration are performed from different aspects in this paper.The main work of this his thesis is summarized as follows:(1) Ice response spectra is proposed based on the idea of a seismic response spectra analysis of str .. uctures.Firstly,ice response spectra on the basis of power spectra density function is established;Secondly,based on the assumption of quadratic parabolic interpolation method,the nonlinear interpolation analysis method of ice response spectra is studied from both theoretical and practical points of view,and the successive computation formulas including ice displacement,velocity and acceleration response spectrum are deduced by Duhamel integral.Furthermore,to analyze the effectivity and applicability of the method, the real temporal curves of ice pressure are used to be studied.The results show that the presented method is more convenient and accurate to study the structural response induced by ice force,also it can be effectively applied in the design of ice resistance.

鉴于此，本文针对冰激桥墩结构振动问题从不同方面展开了一系列与之相关的研究，主要研究内容如下：(1)根据结构抗震反应分析思想提出了冰振反应谱，首先建立了基于功率谱密度函数的冰振反应谱；其次借鉴地震反应谱内插法的思想从理论和实际观点出发，假定在等距离微小时间间隔内冰荷载按二次抛物线规律变化，由Duhamel积分推导出冰振位移、速度以及加速度反应谱的一系列连锁公式，建立了基于非线性内插法的冰振反应谱，并利用实际冰压力时程曲线进行了冰振反应谱数值分析，为以后冰激结构振动的研究提供一种方便、简捷、精确的分析方法，也能够将其有效地应用到结构的抗冰计算中。

This paper discusses the characteristics of the portal frame building constructer and studies optimization method to design them.The systematic analysis of the portal frames steel structural characteristics is done in section 2. And in section 3 and section 4, the structural optimization design is introduced based on the principles of finite element analysis and the technology of Object Oriented Programming in the software ANSYS.

本文系统地分析研究了门式刚架钢结构的特点，在此阶段，以有限元为基础，借助大型有限元ANSYS面向对象程序设计技术进行优化设计，研究基于功能强大的ANSYS作结构优化设计的问题：提出有效的设计变量、优化目标函数(以降低结构重量、充分发挥材料性能为目标)，编写APDL优化程序控制文件，在ANSYS程序上实现门式刚架结构优化设计。

In this paper,a new variable structure robust model reference adaptive control scheme is proposed,which deals with a class of SISO plants under parameter and unmodelled dynamical uncertainties.It is shown that even with the existence of unmodelled dynamics,the output tracking error will converge to zero in finite time, and the SPRcondition for reference model is not required.

摘 要 讨论了含结构不确定SISO系统的变结构模型参考鲁棒自适应控制问题，提出了一种新的变结构控制方法，使得：1系统在同时含参数及结构不确定性时，跟踪误差仍能在有限时间内收敛到零；2无须假设参考模型为SPR函数。

For preparing for the researches of text digital watermarking and advantaging other researchers" development when using the Chinese mathematical expression theory, this paper designs and realizes a development platform of Chinese mathematical expression. It has been proved by experiments that the platform"s function, execution speed and stability can satisfy the requirements of conversion and operation of enormous data.This research found out that the structure information of Chinese have plenty redundant information that can be used by the Chinese mathematical expression for the digital watermarking, the data embedded can possess better robustness. Based on this finding, this paper designs a kind of text digital watermarking method of embedding watermarking by using Chinese structure, and realizes the method by using the Chinese mathematical expression platform.Considering the watermarking embedding algorithms importance to the robustness of the text digital watermarking, this paper makes fully use of the advantage of the Chinese mathematical expression theory to design a kind of layered text method, which has being realized by using the Chinese mathematical expression platform. The layered text method can handle the text as a solid structure, and the embedding data havepreferable robustness.Finally, based on the researches of the text digital watermarking method and the text layered method, this paper integrates the method of making use of the Chinese structure embedding watermarking with the robust algorithm based on text layered, and realizes a brand-new text digital watermarking method. Proved by lots of experiments, this brand-new method has good robustness and better invisibility.

为了为研究工作做准备和方便其他使用汉字数学表达式理论体系的人进行开发，本文基于汉字数学表达式理论设计实现了一个汉字数学表达式平台，实现了Unicode汉字集中的汉字、汉字数学表达式、汉字的Unicode码之间的相互转化、依据汉字数学表达式提取汉字的结构信息、由汉字数学表达式在非中文平台上不依赖字库显示汉字的图像等功能，使用复合文档技术和流压缩技术进行数据的存储，使用对汉字数学表达式进行二叉树拆分来处理汉字数学表达式中包含的信息，使用自定义哈希函数来提高运行速度，实验证明，该平台功能、速度和稳定性完全能满足大量数据的转化和运算要求；通过研究表明汉字的结构信息中存在大量可使用汉字数学表达式理论加以利用的水印加载空间，加载在该空间的数据可以具有较好的鲁棒性，基于此，本文设计了一种利用汉字结构加载水印的文本数字水印方法，并使用汉字数学表达式平台将其实现；由于水印嵌入算法对于文本数字水印的鲁棒性至关重要，本文充分利用汉字数学表达式理论的优点，设计了一种文本分层的方法，并使用汉字数学表达式平台将其实现，使文本成为一个立体的空间，使嵌入在其中的数据具有更好的鲁棒性；最后在基于汉字数学表达式的文本数字水印嵌入方法的研究和基于汉字数学表达式的文本分层方法的研究的基础上，结合利用汉字结构嵌入水印的方法和基于文本分层的抗攻击文本水印嵌入算法实现了一种全新的文本数字水印方法，经实验证明，该方法有良好的鲁棒性和较好的隐蔽性。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。