压点

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。

Examination of the equilibrium status of a point in the salt water zone and the description of piezometric heads at two points ...

通过考察咸淡水界面之下咸水带任意点的压力平衡关系和咸水带及淡水带任意点的水头描述得知，当地下水流处于稳定状态且满足Dupuit假设时，可以根据同一垂直线上界面之下咸水带任意点的咸水测压水头和界面之上淡水带任意点的淡水测压水头确定滨海均质各向同性潜水含水层咸淡水界面的位置。

In order to clear heterogeneous reservoirs waterflooding performance, and decreased interlayer and within-layer contradictions, and improved the water flooding recovery, experimental study should be conducted first, This paper based on Pucheng Sasan reservoir sandstone cores to study object. Multi-point pressure measurement of water flooding oil experimental apparatus was established. Through the three-layer water flooding experiment to study injection strategy, interlayer interference and recovery factors. True sandstone micro-model water flooding used newly developed color visual image analysis system researched water-drive types, forms of residual oil and waterflood efficiency. Percolation mathematical model was established, black oil simulation program was developed, long-core displacement experimental results were matched, pressure and saturation change were researched by the simulation matching results.

为了明确非均质储层注水开发动态过程，减轻由于层间和层内非均质造成的开发矛盾，提高水驱采收率，本文从实验研究出发，以濮城沙三储层岩心为研究对象，建立了一套带多测压点的多层长岩心水驱油实验装置，通过开展三层水驱油实验，研究注水方式、层间干扰以及采收率影响因素；真实砂岩微观模型水驱油实验采用最新研制的彩色可视化图像分析系统研究水驱类型、残余油形成类型以及水驱油效率；建立并求解渗流数学模型，编制黑油模拟程序，对长岩心驱替实验进行拟合，通过拟合结果研究驱替过程中油水饱和度和压力的变化情况等研究工作。

In accordance with time series analysis and dynamic modeling technique, dynamic forecasting model is presented.

通过对测压点水头序列的统计分析，得到其周期性、趋势性及随机扰动性的变化规律。

A Thai-style massage with herbal compresses, is a fusion of massage techniques such as patting, pounding, pummelling, pressure point massage, drainage and stretching.

一泰国式按摩与草本压缩，是一个融合的按摩技术，如轻拍，冲击， pummelling ，压点按摩，排水和伸展。

As the distance away from the entrance increases, the magnitude of pressure undershoots increases at first, then, decreases linearly. But the period of stratified flow increased linearly.

随着测压点离管道入口距离的增大，压力&过降&值先是增加然后线性降低，而短暂分层流周期的大小则线性增大。

The gas flowrate decreasing is associated with the pressure undershoot and temporary stratified flow. The magnitude of pressure undershoots and stratified period are sensitive to the magnitude of gas flowrate change and the distance away from the entrance of pipeline.

气量降低过程会有压力&过降&和短暂分层流型的出现，压力&过降&值和短暂分层流周期的大小除与气体的降低量有关外，还与测压点距管道入口的距离有关。

Presents the position of the constant pressure point for the system with both expansion pipe and circulating pipe.

指出了同时具备膨胀管和循环管的系统中定压点的位置。

Presents the position of the constant pressure point for the system with both expansion pipe and circulatin.

指出了同时具备膨胀管和循环管的系统中定压点的位置。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。