变换

When compared with TL Buck converter, efficiency of this new converter is higher and the DC voltage blocking capacitor[1] can be smaller, when compared with double frequency Buck converter, voltage stress of the high frequency switches is lower, the output capacitor and inductor is smaller, and the dynamic load characteristic is better.

与三电平Buck变换器相比，复合双频Buck变换器具有较高的效率，而且其"隔直"电容可以取得更小。与双频Buck变换器相比，其具有高频开关电压应力低，输出滤波电感、滤波电容小，动态负载性能好等优点。

The first is on the study of spectra technique in boolean function and in its probability function.

得到布尔差分等布尔运算在此映射下的实函数运算，并用有限离散变换实现了从原函数到象函数、到象函数偏差分，以及到布尔差分的象函数的变换，并研究了这一系列变换的性质。

In the dissertation, principles of phase-shifted full-bridge ZVS PWM and push-pull boost converter are analyzed; Reason of duty ratio dropping out and solution measures are introduced at the same time; The magnetic biasing and ZVS methods of Lagging brachium are studied detailedly in the bidirectional DC converters.

在本文中首先分析了移相全桥式ZVS-PWM功率变换和推挽式DC／DC Boost功率变换的工作原理，分析了移相全桥式滞后臂实现零电压关断困难以及占空比丢失的原因以及采取相应的改善措施，分析了双向DC／DC变换器产生偏磁的原因以及采取抗偏磁的措施。

And with the senile texture templates, a caducity transformation based on texture mapping and shape warping is presented.

本文使用基于漫画合成技术的人脸图像年轻变换算法和基于形状变形与纹理映射的人脸图像衰老变换算法，对人脸图像年龄变换做了深入研究。

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 view of crosswell and 3D VSP layout, we use high resolution Radon transform based on Cauchy distribution to perform Radon transform for hole data. In this process, we study discrete dip overlay operator, improve damping factor that affects Radon energy convergence in order to let Radon energy converge, 6 resolve leggy in Radon data, and decouple smoothing effect among each energy group, we use Cauchy distribution to regularize data, let energy focus on one point, and improve Radon resolution. All these work well in wavefield separation. Finally, by inversion results and model trial, we verify the feasibility and stability of this method.

在Radon变换原理分析基础上，采用基于柯西分布的高分辨率线性Radon变换对井孔数据进行Radon变换，其间通过对离散倾角叠加算子求取的研究，及对影响Radon能量收敛的重要参数阻尼因子算法的改进，使数据在Radon域以能量团的形式呈现，得到很好的收敛效果，基本解决了Radon域数据的一定程度的拖尾现象，消除了各能量团之间的平滑效应，采用柯西分布来规则化数据，提高了Radon域的分辨率，Radon域能量也收敛到一个点上，有利于上下行波或纵横波波场分离。

In view of crosswell and 3D VSP layout, we use high resolution Radon transform based on Cauchy distribution to perform Radon transform for hole data. In this process, we study discrete dip overlay operator, improve damping factor that affects Radon energy convergence in order to let Radon energy converge, 6 resolve leggy in Radon data, and decouple smoothing effect among each energy group, we use Cauchy distribution to regularize data, let energy focus on one point, and improve Radon resolution. All these work well in wavefield separation.

在Radon变换原理分析基础上，采用基于柯西分布的高分辨率线性Radon变换对井孔数据进行Radon变换，其间通过对离散倾角叠加算子求取的研究，及对影响Radon能量收敛的重要参数阻尼因子算法的改进，使数据在Radon域以能量团的形式呈现，得到很好的收敛效果，基本解决了Radon域数据的一定程度的拖尾现象，消除了各能量团之间的平滑效应，采用柯西分布来规则化数据，提高了Radon域的分辨率，Radon域能量也收敛到一个点上，有利于上下行波或纵横波波场分离。

Firstly, the new watershed transformation using extended chain code was introduced. Then a new region merging method for solving over-segmentation was discussed. Experiments show the new algorithm can segment the road regions correctly.The structured road edges can be represented by straight line or segmented lines.

首先在分析经典分水岭变换算法的基础上，提出了一种新的基于扩展链码的快速分水岭变换算法，使得分水岭变换更利于实时应用；然后通过对过度分割产生原因的分析，提出了新的基于区域灰度和位置约束的过度分割解决方法，并在道路区域分割应用中取得了良好效果。

In this thesis, I introduce the purpose and meaning of my study in this field and also introduce the definition, characteristic, class and use firstly.

本文首先介绍了该论文课题研究的目的和意义，以及数字水印技术的基本概念、特性、分类、用途等，接着介绍了主要的水印攻击方式以及相应的对策，然后介绍了小波变换的基本理论，包括连续小波变换、离散小波变换、多分辨分析、Mallat算法等。

However, due to the direct conversion characteristic of matrix converter, the drive performance of induction motor is easy to be influenced by input voltage disturbances of MC.

但是，由于矩阵式变换器的直接变换特性，异步电机系统的调速性能易受到矩阵式变换器输入侧电压扰动的影响。

He and Nina moved to California and lived at 2005 Ivar Street, Apt.

他和Nina搬到加州，并在2005年伊瓦尔街，公寓生活。

Droperidol （ potently inhibits transfected HERGchannels and this is the probable mechanism for QT prolongation.

氟哌利多有效地抑制了转染的 HERG 钾通道，可能是 QT 间期延长的机制。