查询词典 harmonics

A new method based on the Fourier-Bessel series is proposed to calculate the higher-order harmonic components of a nonlinear ultrasound field in absorbing medium and an analytical solution of a series form is obtained. A closed analytical solution of the higher-order harmonics in the zeroth-order Bessel ultrasound field and the focused Gaussian ultrasound field is deduced to study the field property, especially the near-field property.

提出了一种基于Fourier-Bessel级数的新方法，用于计算吸收媒质中非线性超声场的高次谐波分量，得到其级数形式的解析解，由此推导出吸收媒质中零阶Bessel超声场、Gauss聚焦超声场高次谐波的封闭解析解，进而对其声场特性尤其是近场特性进行了研究。

Harmonics and other partials accentuation identifies each of the frequencies and its relationship to adjacent frequencies as well as fixed or moving thresholds and makes the appropriate adjustment.

泛音和其他分音的加重识别每个频率和它与邻近频率的关系以及固定的或移动的门限值并且做出适当的调节。

Using the OMA optical multi-channel spectrometry , CCD(1152×1242) camera detect equipment and achromatic aberration camera lens for spatial distinguishing, we carried out the experiments to measure the one- dimension fine structure spectrum of 20 harmonics,and then investigated primarily the measurement system of scattering light.

实验采用OMA光学多道分析谱仪(谱分辨0.1nm )加CCD1152(1242相机探测设备，用消色差的相机镜头作为空间分辨，测量20谐波的一维精细结构谱，对利用散射光测量系统进行了初步探索研究。

Effect of amplitude modulation and phase perturbation on the optimizing parameters of third harmonics generations.

振幅调制和位相扰动对三倍频参数优化的影响。

The third, fifth and seventh harmonics were selected to calculate the pulse width jitter, and the corresponding product of pulse width and angular frequency, 7W, were 1.305, 2.175 and 3.045, respectively. With 25 kHz～5 MHz integration limits, the pulse width jitter was obtained to be 3.08ps.

选择脉冲重复频率的三次、五次和七次谐波的功率谱进行分析，三个谐波级次对应的脉冲宽度角频率积Tω分别为1.305，2.175和3.045，在25 kHz～5 MHz偏移频率范围内，得到的脉冲宽度抖动为3.08ps。

The simplified spherical harmonics method is utilized to discrete the angular variables of Self-Adjoint Angular Flux neutron transport equation as spherical harmonics method has the dis-advantage of large amount of calculation.

针对球谐函数方法求解中子输运方程时计算量大的缺点，将简化球谐函数方法用于离散二阶自共轭中子输运方程的角度变量，同时应用有限元方法在非结构几何下进行空间离散，研究了简化球谐函数方法在SAAF方程中的应用。

Sometimes the series and shunt syntony with main system would enlarge harmonics and make things worse. Active Power Filter, as another kind of filter equipment, begin to make use following the advancement of GTR,GTO, IGBT and etc. Theunique advantage of this new setting is dynamic harmonics canceling. Now, the shunt APF is the most widely used one.

进入80年代以后，随着有源滤波技术的不断深入和用户对谐波问题的重视，以及电力电子技术的飞速发展，大功率可关断器件(GTR，GTO，IGBT等)的不断进步，有源电力滤波器(Active Power Filter， APF)作为抑制电网谐波、补偿供电系统无功功率的新型电力电子装置得到迅速发展，其中又以并联型有源电力滤波器的使用最为广泛。

In view of this problem,a parameter extremum optimization model is developed,in which such error factors as the decaying DC components,nonsynchronous sampling and harmonics are precisely depicted.A new measuring method based on the hybrid genetic algorithmis developed to use this model for finding accurate power system parameters such as the amplitude,phase,frequency and harmonics.

针对这一问题，建立了电力参数极值优化模型，同时对衰减直流分量、非同步采样及谐波等多个误差参数加以精确表示，利用混合遗传算法对该模型进行求解，可得到准确的系统幅值、相位、频率及谐波等电力参数。

And this engenders many harmonics, the harmonics affect the quality of electric energy.

摘 要：随着电力电子技术的发展，大量电力电子装置的使用，产生的谐波电流严重影响了电能质量。

Capacitive rectifier, a traditional rectifier for electronics instrument, can result in a lot of input current harmonics, which brings the main to harmonics distortion.

传统电子设备的电源输入端采用二极管整流和电容滤波，其输入电流含有大量的奇次谐波，对电网造成巨大的谐波污染。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。