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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。

A new non-linear quadratic programming Bayesian prestack three-terms inversion method is developed; Firstly, this method is based on Bayesian parameter estimation theory, Gaussian distribution is used for likelihood function and modified Cauchy distribution is used for prior distribution; Secondly, covariance matrix is used to describe the degree of correlation between the parameters; rock physics relations are used to constrain the inversion results; at last, this method is transformed into non-linear quadratic programming problem, and inversion results are acquired under several constraints.

本文提出了一种基于非线性二次规划的叠前三参数反演方法。首先基于贝叶斯参数估计理论，假设似然函数服从高斯分布，并使待反演的参数服从于改进的Cauchy分布，从而提高了反演结果的分辨率；其次用协方差矩阵来描述参数间的相关程度，进一步提高了反演结果的稳定性；最后将问题转化为一个非线性二次规划的求解问题，并在多种约束下得到问题的解。

Then the boundary element integral equation of interior and exterior form is deduced in detail, also the form with corner coefficient. The significance for numerical calculation and principle of the singular integral is analyzed, and a non-isoparametric transformation method is presented to calculate weak singular integral and Cauchy integral, the method presented provides us a very simple way to computer the two kinds of singular integral of Helmholtz boundary integral equation, and it is easy to program in computer. After the difficulty of the calculation for multi-frequency of Helmholtz boundary element is explained, a method named SECHIEF (Series Expansion Combined Helmholtz Integral Equation Formulation), which is focused on the computational efficiency, is presented.

对结构声辐射的边界积分方程的内部形式与外部形式进行了详细的推导，给出了角点系数的计算方法与边界积分方程的形式，在此基础上，分析了奇异积分产生的原理及其对数值计算的重要性，提出了一种计算奇异积分的非等参(来源：Ae8a8BC论文网www.abclunwen.com)单元的变换方法，该方法给Helmholtz 声学边界积分方程中的弱奇异积分与Cauchy 奇异积分的计算以及编程提供了极大便利。

Love is the only thing that is causeless, that is free; it is beauty, it is skill, it is art.

爱是唯一没有原因的东西，那是自由的；那是美，是技巧，是艺术。

Firstly, oscilloscope control system based on GPIB technique is presented with friendly operation environment to the HIFU system, and it uses multithreading technique in programming to realize real-time recording and display of the signal; Secondly, temperature collection and data recording system is designed, which also could get real-time recording and display of the 16 channel temperature signal, and it's believed to be of great use for further experiments of the HIFU system; Thirdly, multiple ultrasonic phased array's phase shifter is designed,which could provide 8-bit phase control in a range of frequency where the centrical frequency is 1MHZ. Fourthly, the module of serial communication is realized to insure the communication between devices and computer, including both synchronous and asynchronous communication, which enables the system to transfer data reliably and stably; Finally, the module of digital quantity control is accomplished, which provide for upper application the consistent solution to the control of exterior devices via digital interface. It can get or set the devices state using interrupt mode to receive input signal or send output signal.

主要有以下几个方面：设计了基于GPIB的示波器控制系统，给课题的研究工作提供了一个良好的环境，它采用了多线程编程的方法，能够较好的实时显示当前波形并记录数据；设计了温度采集和数据记录系统，能够对16路温度信号进行并行同步的实时采集，用于HIFU剂量学研究中温度场检测和医疗评价；设计了相控阵相位延时电路并且通过调试，满足了课题的相位控制的要求，在中心频率为1MHZ左右的频率范围内都能够达到8-bit相位控制；实现了串口通讯模块，为各项设备与计算机之间的通讯提供保证，它提供同步和异步的通讯能力，使系统能够可靠稳定的传输数据；建立了数字量控制模块，为上层应用程序提供一致的方法使用数字接口控制外部仪器，它使用中断的方式来接收输入或输出设定的开关量信号，从而得到或设定各种仪器的状态。

The Heaven and the Way is the both the changeableness of the universe and the thought to pursue harmony in the world; The Humanity is the thought to pursue harmony in the conflict society by culturing mind, which means a real person must be of disenchantment in thought and self restraint in behavior, and the society is of solicitude for human, all that is the ZhongYong; The Unifying and the Changing is the harmony in evolvement, the essence of the universe and thought;as a thought, it is the Way of communication between human and nature or society; The one is ultimate perfection but that means death, only in its own transcending it becomes the the primary chaos,namely ultimately the Chinese thought.

本文中使用的中国思想区别于一般使用的"中国传统思想"，中国思想具有的自身的本体性意义，它不同于对一般的思想观念的研究，不是研究它所表达的内容的特点和性质，也不是指某种具体思想观念的产生和发展的演变，而是指思想自身作为动力性本质的本体性存在过程；"中国传统思想"则具有它所指称的历史内容，是指中国文化历史进程中具体的思想脉络，当然"中国传统思想"也有概念自身特定的研究意义，但那是建立在全部历史内容的基础上，用来表达中国历史自身的精神特质。

The Heaven and the Way is the both the changeableness of the universe and the thought to pursue harmony in the world; The Humanity is the thought to pursue harmony in the conflict society by culturing mind, which means a real person must be of disenchantment in thought and self restraint in behavior, and the society is of solicitude for human, all that is the ZhongYong; The Unifying and the Changing is the harmony in evolvement, the essence of the universe and thought;as a thought, it is the Way of communication between human and nature or society; The one is ultimate perfection but that means death, only in its own transcending it becomes the primary chaos, namely ultimately the Chinese thought.

天和道既是世界的可变易本质，也是对普世和谐的追求；仁是通过人性的修养追求社会冲突中的和谐，因此它意味着人应当保持思想自觉和行为克制，而社会应当对人关爱，这就是中庸；合和易是演化中的和谐，它是世界和思想的本质，作为思想，它也是人、自然和社会之间的交流；一是终极的完美，但也意味着死亡，只有在它自身的超越中它才成为浑沌之初，这就是终极意义的中国思想。

Bai Ju is beautiful, it is a common breed in chrysanthemum come, it and other chrysanthemum are same, it is to be in what tomb-sweeping day applies this day is very general, its beautiful words is exalted, the origin of its beautiful words and its color is not divided, the ancients and even now, can describe chasteness with white, pure friendship, pure love, pure heart.

白菊花。白色菊花的花语和象征代表意义：高尚白菊花，是菊花中常见的一个品种来的，它和其他菊花一样，都是在清明节这天应用的非常普遍，它的花语为高尚，它的花语的由来和它的颜色是分不开的，古人乃至现在，都会用白色来形容纯洁，纯洁的友谊。

Present news paper color there are many causes of the problems is mainly based on the following points: first, the editing and computer operators lack of professional knowledge of color, the professional quality of pending further enhanced; the other is to have the professional knowledge of chromatology editors did not play an important role, published links exist between 美编 and post need not phenomenon; three is practitioners on the importance of color means understanding is not sufficient, as long as the subject according to your preferences, and that is the color on the color news, which is to use color also will not be deemed to be any mistakes.

造成目前彩报用色问题的原因有许多，主要有以下几点：一是编辑和电脑操作者缺少专业的色彩知识，其业务素质有待进一步提高；二是具有色彩学专业知识的美术编辑没有发挥重要作用，出版环节存在美编与岗位需要之间的脱节现象；三是从业者对色彩手段认识和重视不够，认为只要根据自己的喜好标上色彩，就是彩报了，即使用色不当，也不会被认定为差错。

The mask applying to experiment is opened up and that the mask exposure's device is designed and done. The technologic flow of the MEMS unit's manufacture combining optical score, sacrifice layer, chymic deposit with the SL prototyping technology is researched and experimental sample is done. Taking 3D capacitance micro actuator done by RP technology as a example, the main point of the manufacturing technics is illuminated, the new way manufacturing complex micro mechanical structure is explored.

在介绍了微电子机械系统基本情况的基础上，首次提出了将RP技术应用于MEMS的思想以及平面掩膜式光固化快速成型方案；开发了实验用掩膜，设计并制作了平面曝光成型的实验装置该装置；首次研究了将光刻技术、牺牲层技术、化学淀积镀膜与光固化快速成型制造技术等相结合，来制作MEMS件的工艺流程，并制作了实验样件。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。