分谐波

The fundamental and higher-order harmonic ultrasound fields of a zeroth-order Bessel ultrasound field and focused Gaussian field in absorbing medium are computed and simulated by solving the KZK equation using a frequency domain finite difference method.

通过频域有限差分方法求解KZK方程，对吸收媒质中的零阶Bessel超声场、Gauss聚焦超声场进行计算，得到基波和高次谐波声场的数值解和仿真图，计算仿真结果验证了上述的理论结论。

This is the first time that bifurcation phenomena are observedin closed tube.

首次在驻波管中观测到了次谐波、分岔现象。

For weak nonlinear distortion, the expressions of total harmonic distortion, the second order intermodulation distortion(IM2 ), the third order intermodulation distortion(IM 3) and intercept point(IP 3) are deduced. With the aid of software Multisim, we simulate transistor common emitter amplifier, transistor common emitter amplifier with resistor in emitter, differential amplifier and differential amplifier with resistor between emitters. The simulational results and theoretical analyses are almost the same.

针对弱非线性失真，推导了总谐波人、二阶互调失真( IM2 )、三阶互调失真( IM3)和截点( IP3)的表达式，借助于 Multisim软件，对晶体管共发放大器、发射极带反馈电阻的失发放大器、差分放大器和发射极间带反馈电阻的差分放大器进行了仿真，并与理论结果作了比较，结果令人满意。

The numercial simulation has been carried out, and the experimental results show that this method has been improved significantly comparing with the traditional one in nonlinear optics. Secondly, a second order system of semilinear elliptic equations, which comes from a mathematics model of the electric potential distribution of a media surrounded with the protein, is transformed into a variational problem, the existence of solution of it is proved by using variational principle and Trudinger—Moser inequality, and the relation between the solutions of variational problem and the solutions of its dual problem is obtained.

首先，讨论了非线性光学中的二次谐波产生的耦合方程组，利用变分法证明了耦合方程组非平凡解的存在性，然后进行了数值模拟，实验结果表明文中方法比经典的非线性光学中的方法有较大的改进，这对优化光倍频器件的设计将有所帮助；其次，将一类二阶半线性椭圆型方程组转化为一个变分问题，然后利用变分法和

The theoretic analysis and the practical application prove that using full-wave Fourier transform algorithm in line difference protec

通过理论和实际两方面的对比总结出，对使用矢量同步方法的线路差动保护采用全波差分傅氏算法后可以大大减小谐波带来的同步误差，提高保护装置的可靠性。

Second, the dyadic wavelet analysis and harmonic wavelet analysis and fractal analysis is presented.

其次，在指出基于Fourier变换的时频分析的缺点后，介绍了先进的二进小波分析和谐波小波分析、分形分析。

Based on the Timoshenko-Mindlin hypothesis and the Hamilton Principle, a set of governing equations of motion for the laminated non-circular cylindrical thick shells were founded.Using the Galerkin procedure,the Mathieu equation only with time variable was obtained,and this equation was solved by the method of increase harmonic balance.

基于Timoshenko-Midlin假设及Hamilton变分原理，建立了层合中厚非圆柱壳的非线性运动控制方程，采用伽辽金技术，得到仅含时间参数的Mathieu型方程，然后应用增量谐波平衡法进行求解。

A simultaneously harmonic voltage measurements from a magnetic potential transformer and a capacitor divider on a medium voltage bus show a good frequency response of PT.

对一组PT信号和同一母线的电容分压器分压信号进行谐波比对测量分析表明，中压系统的电磁式电压互感器有较好的频率响应特性。

The two programs are Harmonics.m , which plots low order harmonics and Sectorials.m , which plots high order sectorial harmonics.

两个程式分别是 Harmonics.m 和 Sectorials.m ，前者用於绘制低阶简谐波，后者用於绘制高阶扇形简谐波。

The two programs are Harmonics.m , which plots low order harmonics and Sectorials.m , which plots high order sectorial harmonics.

脚本。两个程序分别是 Harmonics.m 和 Sectorials.m ，前者用于绘制低阶谐波，后者用于绘制高阶扇谐波。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。