差分法

Based on Wavelet Packet Analysis and Smoothed Pseudo Wigner-Ville Distribution, the experiment data is time-frequency analyzed. The experimental results indicate that the amplitude of the laser-induced acoustic waves increases with the laser energy; the frequency coverage is from 0 to 150 KHz, and in the meantime there is a peak located at about 25 KHz. In addition, the spectrum and the peak of frequency are basically stable in spite of the change of laser energy and target texture.

从基本的空泡动力学理论出发，推导了空泡各特征参量之间的关系，进而对空泡动力学模型进行了修正；采用有限差分法对空泡脉动进行数值模拟，得到了空泡脉动特性随液体粘性、空泡含气量、表面张力以及可压缩性的变化规律；实验上采用光偏转测试装置探测了激光空泡脉动以及空泡溃灭的细节过程，进而分析了液体粘性和作用激光能量对空泡脉动周期、泡半径及泡能等特征参数的影响。

The major concern during laser irradiation of teeth is the high potential of tissue overheating resulting high temperatures that can spread in toward the dentin,causing irreversible damage to cells presented in the pulp chamber and leading to cell death,so the related laser irradiation parameters should be controlled strictly.

激光辐照牙齿时所产生的温升容易引起牙髓细胞不可逆的损伤，导致牙髓细胞坏死，因此必须对相关的激光参数加以控制。建立了激光与牙齿相互作用的热传输模型，利用Crank-N icolson有限差分法数值模拟了不同Nd∶YAG激光参数照射下牙齿表面及内部的温度场的分布。

Three-dimension temperature field of flame tube is calculated by FDM, which may describe the actually working case of flame tube.

使用有限差分法分析火焰筒的三维温度场，该方法能真实地模拟燃烧室的实际工作情况。

Mathematical model of hydrodynamic action in the free abrasive wire saw slicing process was established.

建立了游离磨料线锯切片过程中流体动压效应的数学模型，并采用有限差分法进行了数值分析，得到了游离磨料线锯切片的流体动压力分布和膜厚。

Metallic wire grating in terahertz frequency was designed and fabricated by femtosecond micromaching and sputtering technique.And the polarized transmission spectra of the gratings were characterized by terahertz time domain spectroscopy ,and the theoretical simulation based on FDTD method show a good agreement with experimental results.

结合飞秒微加工和磁控溅射技术，在熔融石英衬底上设计并制作了不同结构的太赫兹波段金属线栅，并通过太赫兹时域光谱系统研究了线栅结构对太赫兹偏振透射特性的影响，并用有限时域差分法对实验进行了模拟验证。

The new method of Fourier's expansion-difference method that was presented newly for analyzing arbitrary-shaped grooveguide is adopted in order to solve some practical application problems of wave guide in this paper.

为了更便捷地解决波导和谐振腔的实际应用问题，本文采用已提出的一种分析任意截面槽波导的傅立叶展开-差分法对这类电磁场边值问题进行分析计算。

For sucker rod pumping system, it commonly used the explicit difference method to evaluate a rod pumping performance.

对石油开采中的有杆抽油系统，通常采用显式差分法进行求解。

With the aid of the method of finite differences, we get the slip line field around a shaft, and analysed the law of the development of shaft-earth-pressure .

并借助有限差分法求解竖井周围的滑移线场，分析了竖井地压的作用与变化规律。

The self-life of the galactosidase-electrode is between 15 and 20 days while the glucose oxidase-electrode is more than 60 days.

该系统可同时测定样品中乳糖和葡萄糖的含量，乳糖电极的葡萄糖干扰用差分法消除。

Our approach to energy subbands in the active region of QCL is k · p method. Electron eigenvalues and eigenstates are calculated by solving Schrodinger and Poisson equations self-consistently.

k·p微扰方法下，利用有限差分法求解了化合物半导体的有效质量方程，在计算中考虑了超晶格界面处电子有效质量不连续性，自洽求解了掺杂有源区在不同外加电场下的薛定谔方程和泊松方程。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。