查询词典 fast break

The model of adiabatic spherical to columnar hydrogen bubble growth in large leak sodium water reaction as well as the model of secondary loop pressure propagation with the one dimensional characteristic method are established under one double ended guillotine tube break in the steam generator of liquid metal cooled fast breeder reactor.

研究建立了钠冷快堆蒸汽发生器在单管束发生双端断裂情况下钠水反应中气泡从球形到柱状的变温绝热生长模型，及采用一维特征线方法建立的压力波在快堆二回路中的传播模型。模型中考虑了爆破膜、管壁弹性变形和气蚀的影响。

This paper combines with pipeline delivery of our countrys actual conditions and other methods of detection and location. To the leakage characteristic of the fault to the long-distance natural gas pipeline, a method is raised, which is on the basis of wavelet and negative-pressure-wave to detect the leakage and locate. Jobs in this paper are as follows:Multi-resolution decomposition and reconstruction of wavelet transform is utilized to filter the noises, which the leakage brings the noises of negative-pressure-wave. The research is worked in the wavelet and wavelet packet filter. The wavelet transform have a fast and accurate recognition capability to signal singularity. This paper chooses wavelet technology to catch the break point of pressure signal.

本文结合我国管道输送的实际情况和目前现有的各种泄漏检测与定位方法，针对天然气长输管线泄漏故障的特点，提出了基于小波分析和负压波相结合的方法检测泄漏并定位，其中主要进行了以下几个方面的工作：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降噪处理，并对小波及小波包优化的降噪效果进行对比性研究；利用小波变换技术对信号奇异点的快速、准确的识别能力，捕捉负压波信号的突变点，从而判断是否有泄漏发生。

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。

Dependent on the past research in seaice, in Bohai Sea, in 2003-2004 winter and 2004-2005 winter with level ice for the target we open the field experiments to study the essential spectrum characteristic of ice, removing by testing means various nonessential factor for sea water in the fixing big ice plate, building up 170 growth conditions to look like under the natural condition, the growth expect different sample series; in 2004-2005 winter and 2005-2006 winter continue two pass to break thorough Bohai Sea in the ship to collect 59 sea ice sample that have the non-essential ice factors in winter, open the influence research that the field hangs sand to contribute to the spectrum of the ice body; in 2005-2006 winter, fast ice to open the field spectrum curves to coast and analytical research.

总结前人的研究成果和开展一系列的室内实验，在渤海—北半球纬度最低的结冰海域，于2003/2004、2004/2005 连续两个冬季以单层平整冰为目标开展实验研究一年生海冰的冰体本质光谱特征，在固定冰盘上以实验手段摒除各种光谱干扰因素，在自然条件下建立170 个生长条件近似、生长期不同的样本系列；于 2004/2005、2005/2006 连续两个冬季通过破冰船深入渤海采集59 个具有非冰体本质因素的海冰样本，开展悬沙对冰体反射光谱的影响研究；于2005/2006 冬季，针对沿岸固定冰开展光谱测量和分析研究。

He is good at pass the ball,fast attack and break through.

他很擅长传球，快攻和突破。

I have already had my break fast.

我已经吃过早饭了。

If you run too fast you will break your neck .

如果你跑得太快，你会送命的。

She doesn't eat much break fast.

她早点吃得不多。

I fast for you and I break fast with what You provide me.

主啊！我为你封斋，我以你所赐的给养开斋。

Lugalbanda was a god and shepherd king of Uruk where he was worshipped for over a thousand years.

Lugalbanda 是神和被崇拜了一千年多 Uruk古埃及喜克索王朝国王。

I am coming just now,' and went on perfuming himself with Hunut, then he came and sat.

我来只是现在，'歼灭战perfuming自己与胡努特，那麼，他来到和SAT 。