奇异变换

Secondly, by applying inverse Fourier integral transform to the displacement, and uniting the constitutive and geometrical equations, the analytical expression of stress in Laplace domain were derived. Thirdly, by defining dislocation density functions, the Cauchy singular integral equations were obtained according to the boundary condition and interface connection conditions, and the problem was reduced to algebraic equations by Chebyshev orthogonal polynomial. Based the these, the unknown coefficient of the algebraic equations can be solved by Schmidt method. Finally, the time response of dynamic stress intensity factor and energy release rate are obtained by inverse Laplace transform.

首先，利用积分变换方法，推导出粘弹性层的控制方程组；其次，引入位错密度函数，并结合边界条件和界面连接条件，导出反映裂纹尖端奇异性的Cauchy型奇异积分方程组，然后，应用Chebyshev正交多项式化奇异积分方程组为代数方程组，并采用Schmidt方法对其数值求解，最后，经过Laplace逆变换，求得动态应力强度因子和能量释放率的时间响应。

A new non-conforming finite element FE eigenanalysis method is developed to determine the order and angular variation of singular stress states at material and geometric discontinuities in anisotropic materials subject to antiplane shear loading.

提出采用一种非协调元有限元特征法来计算各向异性材料在反平面剪切载荷作用下的奇性应力指数和奇性场角分布。该方法没有采用奇异变换技术。与以前的几种解析法比较，结果表明这种方法的收敛性好，精度高，可以求解关于复杂几何体问题

The main jobs of the paper are as follows, Multi-scale decomposition and reconstruction of wavelet transform is utilized to filter the noise of negative-pressure-wave, which is brought by leakage. With the capacity to detect the signal singularity quickly and accurately, wavelet transform was used to catch the break point of pressure signal. Accordingly, the work improved the location accuracy.

主要研究工作有：利用小波变换的多分辨率分解和重构技术，对采集到的管道泄漏产生的负压波信号进行消噪处理，并对几个影响消噪质量的关键因素及其选取方法进行了分析；再利用小波变换技术对信号奇异点的快速、准确的识别能力，对经消噪后的负压波信号进行奇异点捕捉，从而实现更精确的单条燃气管道泄漏定位。

Because the temperature along the pipeline is not a constant, it changes the velocity of the negative-pressure-wave; the Romberg algorithm of numeric integral and the searching for algorithm are emloyed to locate the leakage.Multi-scale decomposition and reconstruction of wavelet transform is applied to filter the noise of negative-pressure-wave, which was brought by leakage. With the capacity to detect the signal singularity fast and accurately, wavelet transform was used to catch the break point of pressure signal. The work improved the accuracy of Δt in location formula, and the location accuracy is improved.

利用小波变换的多分辨分析和重构技术，对采集到的管道发生泄漏时产生的负压波信号进行了消噪处理；并利用小波变换技术对信号奇异点快速、准确的识别能力，对经过消噪处理后的负压波信号进行了奇异点捕捉，准确确定了定位公式中上、下游站点采集到的负压波奇异点的时间差△t，从而提高了定位的精度。

At the same time, combining with the actual condition of delivery pipeline of our country and some prevalent leak detection and location methods, this paper raised a method, which is based on wavelet analysis and negative- pressure-wave to detect and locate the leakage. Jobs in the paper are as follows:As affected by gas density, pressure, specific heat and pipe material, the velocity of negative-pressure-wave improved depending on the energy conservation. At one time, taking the affection of velocity of gas flow, the location formula was modified in some degree.When locating the leaks with location formula, the iterative approach algorithm was adopted as a new method to increase the location accuracy level of system.Multi-scale decomposition and reconstruction of wavelet transform is utilized to filter the noise of negative-pressure-wave, which was brought by leakage. With the capacity to detect the signal singularity fast and accurately, wavelet transform was used to catch the break point of pressure signal. The work improved the accuracy of At in location formula, accordingly improved the location accuracy.Wavelet is a suitable tool for signal analysis. The distinct character is that the mother-wavelet is of optional. That means choosing different mother-wavelet will get different analysis result. So we studied how to choose mother-wavelet and its scale for signal singularity detection. The method is to choose a wavelet by regularities of the wavelet and the signal.Finally, a plan, which bases on SCADA system for inspection and detection of natural gas leakage, is proposed in the article.

其中，主要进行了以下几方面的工作：针对泄漏产生的负压波在管道中的传播速度受媒介的密度、压力、比热及材质等因素的影响，而非声波在空气中传播的速度，本文利用能量守恒原理，对其进行了修正；考虑到管内气体流速对压力波速的影响，对原始的负压波定位公式进行了一定程度的改进，并在利用定位公式进行泄漏点定位时采用逐步迭代逼近算法，提高了系统的定位精度；利用小波变换的多分辨率分解和重构技术，对采集到的管道发生泄漏时产生的负压波信号进行了降噪处理；并利用小波变换技术对信号奇异点的快速、准确的识别能力，对经上述消噪后的负压波信号进行了奇异点捕捉，精确捕捉的结果提高了定位公式中上下游站点采集到的负压波奇异点的时间差△t的精度，从而进一步提高了定位的精度；考虑到小波变换是一种基波可变的信号分析工具，也就是说，不同的小波基波对信号分析的结果将有很大差别，这势必影响最终的处理结果，因此，我们又对比分析了本课题中小波基及尺度的选择问题，依据规则性系数相似性原理对母小波的选择进行了探索性研究；最后，还提出了基于SCADA的泄漏检测与定位系统的软件开发构想及系统的嵌入方案。

In chapter 3,we study the Zakharov-Kuznetsov-Modified Equal-Width equation by employing the extended Jacobi elliptic function expansion method and obtain some new solutions of Jacobi elliptic function type of the ZK-MEW equation.;Secondly,using sn-cn method,we study K(m,n,1) equation and obtained some new exact solutions when k=s=3,especially obtained abundand solitary solutions and trigonometric function solutions when m→0 and m→1;In chapter 4,Painleve singular analysis was applied to nonlinear PDE with variable coefficients.

第四章将Painleve奇性分析方法应用到带阻尼项的变系数Burgers方程中，并得到了该类Burgers方程具有Painleve性质的条件，给出了该类Burgers方程的Backlund变换，用所得Backlund变换得到了若干精确孤立波解，包括奇异孤立波解，这些解不等同于行波型孤立波解；用齐次平衡法得到了对数型DBM方程的Backlund变换，并获得了DBM方程的各种孤立波解，包括尖峰孤立波解和奇异尖峰孤立波解。

The sufficient conditions to guarantee robust exponential stability for the closed-loop systems are obtained based on Linear Matrix Inequality, moreover, the approach of design of robust H# output feedback controller is introduced.3 The problem of reliable H# control for a class of Lur"e systems with polytopic uncertainties is studied when all control components are operational as well as when some control components experience failures, the design approach of reliable H# controller is also obtained.4 Considering a class of uncertain Lur"e singular system with time-delays, the problem of robust stability is investigated based on Barbalats Lemma and nonsingular linear transformation of model reduction.

针对一类不确定Lur'e奇异时滞系统，基于Barbalat引理以及非奇异降阶变换，讨论了Lur'e奇异时滞系统的鲁棒稳定问题，提出了鲁棒H_∞状态浙江大学博士学位论文反馈控制器的设计方法。5、针对一类具有饱和执行器的不确定Lur'e奇异系统，提出了时滞依赖的鲁棒稳定与鲁棒二次镇定的充分条件，所的结果不需要参数的整定。6、针对任意协方差有界的有色噪声，讨论了一类不确定Lur'e奇异系统的鲁棒凡滤波问题，得出了鲁棒几滤波器设计的充分条件。7、针对一类不确定Lur'e时滞系统，通过线性变换，把它转换成奇异系统，根据奇异系统鲁棒控制理论所得出的鲁棒稳定与鲁棒镇定控制器设计的充分条件具有很小的保守性。

Compared with the existing finite element eigenanalysis method[8]for asymptotic fields near the crack tip, current method has the following several characteristics: The jump-off that educes the virtue work formula is different; when solving the characteristic formula with FEM, the form of the element is non-confirming element; the singular transformation technique is not used in the assumption of displacement fields surrounding the wedge tip.

该方法与过去的有限元特征分析方法[8]相比的显著特点是：导出虚功原理的出发点不同；有限元单元形式为非协调元；楔形体端部邻域内的位移场假定没有采用奇异变换技术。

There are the following several points different from existing finite element eigenanalysis methods for asymptotic fields near the crack tip:(1)The jump-off that educes the formula is different.(2)The form of the element is a ad hoc element.(3)The singular transformation technique is not used in the assumption of displacement fields surrounding the wedge tip.

该方法与过去原有求解裂纹端部近似场的有限元特征分析方法有几点不同：(1)导出公式的出发点不同；(2)单元形式为高次内插单元；(3)尖劈端部邻域内的位移场假定没有采用奇异变换技术。

In order to improve the precision of the altimetry gravity computed by the inverse Stokes formula, the geoidal height of the innermost area is expressed as double cubic polynomial, and a formula to calculate gravity anomaly of this area is derived after the non-singular transformation is introduced.

为提高利用逆Stokes公式反演测高重力的精度，将中央区大地水准面高表示成双三次多项式插值形式，引入了非奇异变换，推导出了重力异常的计算公式。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。