查询词典 difference frequency

Experiment shows that any liquid has its own especial electrical resonance frequency, and electrical resonance frequency is related with the characters of the liquid itself. As soon as any of the characteristics of the liquid changed such as component,thickness,density and viscidity,the frequency of the liquid electrical resonance will changed.

利用液体的这种电谐振特性，我们来测量血浆凝固过程中谐振频率的变化；当血浆任何性质发生变化，那么这时的血浆已经不是原来的血浆了，其谐振频率一定会发生变化。

The simulation results indicate that H_∞mixed sensitivity controller with PI current loop can improve the capability of low frequency noise enhancement and high frequency enervation in wide frequency band, and attenuate noise of torque sensor. The designed control system for EPS system exhibits good robust performances in assist tracking and anti-disturbance, greatly enhances the returnability, driver\'s steering feel, handling characteristic.

通过仿真结果分析表明基于PI电流环的混合灵敏度鲁棒H_∞控制器能在较宽频带范围内增强地面低频信号、削弱高频信号和抑制转矩传感器的噪声，所设计的控制器有较强鲁棒性，助力跟踪能力和抗干扰能力，能有效改善车辆的转向回正特性，提供给驾驶员较为满意的路感，提高车辆的转向操纵性能。

The results of the study are as follows: 1 Wigner′s time-frequency analysis of the geoacoustic signal is of a clear physical meaning, which can be described as the energy distribution in time and frequency domain, and can reveal the frequency spectrum essential features of non-stationary geoacoustic signal.

研究表明：1。地声信号的Wigner时-频分析具有明确的物理意义，它可表述为信号在时间和频率域上的能量分布，揭示了非稳态地声信号频谱的本质特征。

Therefore the dispersion curves obtained in the field are primarily consisted of the first mode. For a heterogeneous elastic solid consisting of three homogeneous layers whose interlayer has low velocity, the phase velocity V〓 of the first mode will also close up to the Rayleigh wave velocity of the bottom layer when frequency f→OHz, but V〓 of the first mode will close up to the shear wave velocity of the interlayer when f→∞, and there is a cut-off frequency at high frequency region for the first mode and V〓 close up to the compressional velocity of interlayer when interlayer is liquid.

当三层固体介质中存在软夹层时，若f→OHz，则其基阶模式的相速度V〓→V〓（V〓为最底层介质的瑞利波速度）；若f→∞，其基阶模式V〓→V〓（V〓为中间层介质的横波速度）；若三层介质中存在液体夹层，当f→OHz时，基阶模式V〓→V〓，而基阶模式在高频段存在一个截止频率，截止频率处的瑞利波速度V〓→V〓；由此可判定，野外实测的相速度频散曲线不仅有基阶导波模式，同时还应有高阶导波模式波的存在，接收信号中存在模式间的跳跃，因此频散曲线会产生"之"字形现象。

Holding the input energy and actuator volume fixedness, the active frequency has no effect on jet velocity. But the recovery stage time shorten with the increase of active frequency. So, the choice of active frequency is under consider of the temperature resistance for actuator.

在输入能量和腔体体积不变时，激发频率的提高对合成射流的最大速度没有明显的影响，但缩短了腔体内气体的冷却时间，实验时对激发频率的控制首要考虑腔体的耐温能力。

Characterization of the nature of the forced vibration amplitude of the forced vibration frequency and phase frequency characteristics (amplitude and phase frequency characteristics).

表征受迫振动的性质是受迫振动的振幅频率特性和相位频率特性。

A set of complex Morlet wavelet are applied on projection slice of each direction to decompose each projection into several frequency channels,the average and variance extracted are computed in each frequency channel,and then linear regression model is employed to computer realationship feature between frequency channels.1-D DFT is applied to features and the amplitudes of Fourier coefficient are selected as features,then the extracted features are rotation invariant.

该算法是将一定大小的图像进行二维傅里叶变换；其次在变换后的图像中央选择一个圆盘区域，并在方向［0°，180°］内进行等间隔角度频率抽样，实现方向分解，使用一组复Morlet小波对每个方向上的映射切片进行小波变换，从而实现多通道频率分解；在各个频率通道中计算均值和方差作为特征，并利用线性回归模型计算频率通道之间的关系特征；将特征沿方向进行一维傅里叶变换并取其幅值，从而得到旋转不变性特征。

The high efficiency transistor development causes the frequency changer the construction cost more and more to be also low, from the cost and the performance considered selects PLC to the frequency changer control realization frequency conversion velocity modulation.

大功率晶体管的开发使变频器的造价也越来越低，从成本和性能考虑选用PLC对变频器控制实现变频调速。

There are keyboard and liquid crystal to demonstrate window on the frequency converter's control of face, but it can only realize manual operation, for realize the automatic control so we introduce SCM technology, as the result, between MCU and the frequency changer data communication can enhance the control ability and area of the frequency changer.

随着变频调速技术的发展，变频器调速已成为交流调速的主流，在化纤、纺织、钢铁、机械、造纸等行业得到广泛的应用。变频器控制面板上配有键盘及液晶显示窗口，但只能实现手工操作，为了进行自动化控制，因此引进单片机技术，实现单片机与变频器之间的数据通信，提高变频器的控制能力和控制范围。

This text mainly is to panorama video frequency picture, the usage partitions new calculate way automatically according to the video frequency object of timespace consociation at preparing processing stage's ash to video frequency sequence degree diagram to carry on a partial contrast degree to strengthen a processing, increasing foreground object and the contrast degree of background, the filter which passes 3 ×s 3 templates filters in addition to contrast degree strengthen after of lead go into of a little amount 噪 voice;Then aim at the circumstance of complicated background, the calculate way in the text puts forward the covariance characteristic backlog which makes use of immediately signal to get the background that the calculate way needs, overcoming the irregularity that the handicraft obtains background, carrying out a background information to obtain automatically;The standpoint put forward a background backlog finally to categorize a discussion in the process, solved object stop sport time is longer result in the partition throw the problem for losing.

本文主要是对全景视频图像，运用基于时空联合的视频对象自动分割新算法，在预处理阶段对视频序列的灰度图进行局部对比度增强处理，增加前景物体与背景的对比度，通过3×3模板的滤波器滤除对比度增强后的引入的少量噪声；然后针对复杂背景的情况，文中的算法提出利用随即信号的统计特性积累得到算法所需的背景，克服手工获取背景的弊端，实现背景信息的自动获取；最后提出背景积累过程中分类讨论的观点，解决了物体停止运动时间较长时造成分割丢失的问题。

Salt is good, but if the salt becomes flat and tasteless, with what do you season it?

14：33 盐本是好的，盐若失了味，可用什么叫它再咸呢？

He reiterated that the PLA is an army of the people under the leadership of the Communist Party of China.

他重申，人民解放军是在中国共产党领导下的人民军队。