查询词典 difference frequency

A frequency-domain research tool for calculating the initial amplitude,phase,frequency and time constant of fault transient components in complicated networks is developed.

为计算复杂电力网络故障暂态分量的初始幅值、相位、频率和时间常数，开发了一套新的频域计算方法和研究工具。

Network analyzers provide a method for measurement of frequency translating devices and these methods are more accurate and can save more time. According the principles of scalar network analyzer and vector network analyzer the authors introduced methods to measure conversion loss of frequency translating devices using scalar network analyzer and methods to measure conversion loss and phase using vector network analyzer.

摘 要：网络分析仪为测量变频器件提供了快速而准确的测量方法，根据标量网络分析仪和矢量网络分析仪的测量原理，详细介绍了用标网测量变频器变频损耗的方法，以及用矢网测量变频损耗和相位的方法。

ConclusionThe factors that significantly influenced L* value in facultative parts were exposed time and the frequency of using sunscreen, factors that influenced b* value in facultative parts was the frequency of using sunscreen, factors that influenced L* value,a* value and b* value in constitutive parts was skin phototype.

对曝光部位L*值影响最大的是日光曝露量和使用防晒霜频率；对曝光部位b*值影响最大的是使用防晒霜频率；对非曝光部位L*值、a*值和b*值影响最大的是皮肤光类型。

"Modulation Domain" is a plane domain which is consisted of frequency and time of signals. It is necessary field to measure signals in three- dimension space of signal(time domain, frequency domain and modulation domain).

调制域是由信号的时间和频率两个轴构成的平面域，是对信号进行三维测量不可缺少的一个测试域。

The frequency spectrum of the electric field, produced by an electric current dipole on the surface of the uniform conductive and polarizable earth, is transformed into time spectrum, with or without some random error added, and the time spectrum is then inversely transformed into the frequency domain.

基于层状导电和可极化大地表面，电偶源电场的时间谱在无随机干扰和有随机干扰时，进行频谱转换的计算结果，证明了时—频转换的误差传递问题严重。

In order to improve the frequency resolution, realize high precision frequency estimation, this thesis proposes the high resolution polynomial Wigner-Ville distribution using Chirp-Z transform, the validity of this algorithm is verified using synthesized data.

为了提高基于FFT的谱分析算法的分辨率，实现高精度的频率估计，提出了利用Chirp-Z变换的频率高分辨多项式Wigner-ville分布，并用合成的仿真数据，验证了上述算法的有效性和正确性。

External regulator of positive feedback is variation of precipitation amount and frequency of extreme precipitation. It is shown that desertification is predetermined by the decreased precipitation as well as by the decrease in frequency of precipitation. In the second half of 20th century importance of man-induced degradation of dry lands as additional regulator of positive feedback has been increased.

正反馈的外部调节因子是降水量的变化和极端降水事件的出现频率，降水量减少以及降水频率的降低直接影响沙漠化的程度。20世纪下半叶，人类因素导致的干旱土地退化作为另外的正反馈调节因子，其重要性正在增加。

In the design of the power supply, the main circuit topology frame uses full-bridge series resonant switching and parallel load connection, in which, four MOSFETs are adopted as the power switches, and by four pulses which UC3879 produces, high frequency operation and fast response are realized. In addition, the MOSFET in the switching power supply has no hard turn-on or turn-off situation in transition, thus the disturbance to the power system is avoided. Especially,by the use of high frequency transformer, PQ50/50, the switching power system can provide the steady discharge current without any amperite.

此开关电源采用全桥软开关技术、串联谐振并联输出，四个MOSFET管为主控制开关元件，通过脉冲产生电路UC3879产生的四路相关脉冲实现了高频交替开关，同时能快速响应输出的各种变化；避免了开关管的硬开关，提高了转换效率，另外通过采用高频变压器PQ50/50隔离了原副边，减小了高次谐波对电网干扰；无需镇流电阻也可实现气体稳定放电。

In order to further reveal the damage mechanisms of repetitive frequency laser the influence of repetitive frequency laser pre-conditioning on the absorption of optical coatings was also investigated.

为了进一步分析损伤机制，研究了重复频率激光预处理对光学薄膜吸收的影响。

In this paper, a new and novel method has been introduced to degum apocynum venetum, that is to pretreat apocynum venetum with microwave, and then ret with low-frequency ultrasonic and high-frequency ultrasonic under alkaline condition.

文章针对罗布麻胶质含量高，脱胶比较困难的特点，介绍了一种新型的脱胶方法，即利用微波预处理、低频超声波和高频超声波相结合的方法对罗布麻进行脱胶处理。

For the head-teacher of the class said that I had seriously broken the school rules,which led me to a three-day suspend class.

为什么呢？因为我的班主任说我严重的违反了校规，于是让我停课三天。

Many of them believe that the conversion of thousands of working-class folk in England spared that nation from the mass carnage and the tyranny that came with the revolution in France.

他们之中有许多人相信，在英国数以千计的劳工阶级之悔改信主使英国免於遭受如法国大革命所造成的大屠杀和专制暴政。