频率

Physics The increase in amplitude of oscillation of an electric or mechanical system exposed to a periodic force whose frequency is equal or very close to the natural undamped frequency of the system.

磁共振：受周期力作用的电动或机械系统的振荡幅度的增加，该周期力的频率等于或非常接近系统固有的不减弱的频率

In ground testing research of some large airplane and aerocraft, suspend structure of sky need to be simulated. As a lower natural frequency and a good underprop, air spring can satisfy the need of the testing research. In this paper, a calculating model of air spring was built by ABAQUS.

一些大型的飞机，航天器等在做地面试验的时候，需要模拟空中的悬浮结构，由于自身的固有频率比较低，所以需要更低固有频率的支撑物，而空气弹簧正好可以满足试验的需要。

With the premise of that valid chip forming area (the valid uniplanar inductive area of capacitance sensor) keeps stable, experiment results showed that with the definite forming height and density of chip when the moisture content varied in ranges of 5% to 25% were definite, the moisture content was exponent function as measuring frequency; when the moisture ranged in 25% to 45%, there was linear relationship between measuring frequency and moisture content of chip.

在刨花的有效铺装面积保持一定(即为电容传感器的有效平面感应区)的前提下，试验表明：当刨花的铺装高度和密度一定时，刨花的含水率5≤MC＜25％，测试频率与刨花的含水率成指数关系：刨花的含水率25≤MC＜45％时，测试频率与刨花的含水率成线性关系。

The method of equal accuracy frequency measure can remove the errors of unitage and keep the high accuracy constant in the whole measure frequency segment. So the signal frequency has measured is high or low can't influence its accuracy.

等精度频率测量方法消除了量化误差，可以在整个测试频段内保持高精度不变，其精度不会因被测信号频率的高低而发生变化。

The vibrational frequency and the mean number of phonons of surface polaron are derived by using improved linear combination operator and unitary transformation method.

采用Tokuda改进的线性组合算符和幺正变换方法导出了表面极化子的振动频率和声子平均数，讨论了多原子晶体中强耦合表面极化子的振动频率和声子平均数与拉格朗日乘子u和电子—声子耦合参数α的关系。

Using MATLAB, the changes of frequency and power in every area of the two-area and three-area combined systems were simulated respectively and the result shows that the revised ACE controls the changes of frequency and power better than the unrevised one.

利用MATLAB分别对双区域和三区域联合系统中的每个区域中的频率变化和功率变化进行仿真，结果表明，采用修正后的区域控制误差控制下的频率变化和功率变化要比未修正的控制性能好。

The distribution of gear's contact stress, root stress, and contact engagement line in the engagement situation of gear pairs, were obtained on the base of explicit integration method. 3. Adopting the method of system matrix, the torsional vibration differential equation of general shafting was gained. The simple harmonic forms of excitation torque under the normal combustion or piston flameout of in-line engine and v-type engine were analysed. The decoupled algorithm of free vibration and forced vibration and the solution to the vibration damper's energy of resistance and the off-resonance calculation were studied. The sensitivity formulations of the natural frequency and vibration mode to physical parameters of system were derived by solving the eigenvalue problem. These sensitivity formulations provided the theoretical base for the dynamic modification of structure.

运用系统矩阵法建立了轴系的扭振微分方程，并对直列和V型发动机在正常发火和气缸熄火工况下的激振力矩进行了详细的简谐分析；基于精确方法推导了自由振动和强迫振动的解耦算法，给出了能量法计算中的减振器阻尼功求解和非共振计算方法；并研究了曲轴系扭振非线性分析中的变惯量问题，得到了单缸转动惯量的精确求解公式以及变惯量和固有频率的关系式；最后，从特征方程和振型正交性出发，推导了固有频率和振型对轴系转动惯量和刚度等物理参数的灵敏度，为扭振系统的结构动力学修改提供了理论基础。

The charts of velocity vector of flow field outside the tube under five conditions with amplitude 1.3 mm and frequency 5—25 Hz were obtained,and the cosine of average synergy angle of flow field outside the tube was calculated.

实验及模拟结果表明：振动能够显著增加管外近壁区的流体速度，能够在振动方向上的管壁两侧形成有效的冲刷，随着振动频率的升高其管外近壁区的平均速度近似呈线性增加，在共振点出现峰值；相同区域内振动工况的平均场协同角余弦值要明显大于无振动工况，但不同振动频率间的场协同角余弦值变化较小。

The theoretical model of uniform droplet spray process had been established in this thesis. The calculation method for theoretical value of jet velocity and optimal frequency had been developed. Therefore the theoretical value and regularity of jet velocity and optimal frequency under different spray pressure were obtained, so the theoretical prediction for spray result had been realized. This not only offers comparison parameter for simulation results, but also will guide the proper determination of process parameters.

本文建立了均匀液滴喷射过程的理论模型，导出了射流速度和最优频率的理论值计算方法，从而得出了不同喷射压强下的射流速度和最优频率的理论值及所存在的规律，实现了对喷射结果的理论预测，不但为模拟结果提供了对比参数，而且对于合理选取工艺参数具有指导意义。

We need frequencies even higher than those we call very high frequency.

我们所需要的频率甚至比我们称之为甚高频的频率还要高。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐