first harmonic

1. With the first harmonic and its second harmonic the even order harmonics can be obtained.
   并定性解释了其产生机制和谐波效率提高的原因。
2. Thus a smaller membrane gives off a higher first harmonic.
   较小的膜发出较高的第一陪音。
3. If the frequency of a laser is modulated sinusoidally, the first harmonic component of saturated absorption signal can be used as error signal to stabilize the frequency of the laser.
   对激光器进行频率调制，检测原子分子饱和吸收信号中的一次谐波成分得到频率误差信号，反馈控制可以实现激光频率的稳定。
4. First Harmonic Saturated Absorption Frequency Stabilization of Lasers Using Sampling Integration Technique
   利用取样积分实现激光饱和吸收一次谐波稳频
5. Phase splitting reactive power compensation of first harmonic in low voltage distribution network by computer controlled thyristor switch
   微机控制的晶闸管开关型低压配电网基波无功分相补偿
6. Through the method of curve fitting, the eccentric motion which is of the same frequency as the rotary speed is separated ( effectively) from the signals in the first harmonic component. Thus the rotational error of the spindle is determined correctly.
   应用数学方法曲线拟合法对测量信号中与转速同频的偏心运动和主轴误差运动中的一次误差运动进行了有效的识别分离，正确消除了偏心运动，实现了主轴误差的准确评定。
7. These methods can't be used not only to analyze the non integral order harmonics, but to distinguish the eccentricity and the first harmonic, and contain the lager nonlinear error.
   这些方法不能分析非整次谐波，不能区分一次谐波和偏心分量，并且含有较大的非线性误差。
8. Even if inspiring frequency is far from frequency of the derived system, first harmonic, super harmonic and combined harmonic resonance may take place respectively in the normal speed range of an actual gear system, because of time-varying mesh stiffness.
   即使激励频率远大于派生系统的固有频率，在实际的物理系统中，由于时变啮合刚度的影响，也可能出现主共振、谐共振和组合共振。
9. The effect of different topographic scattering targets on the ( ratio) detection was measured and analyzed. The results show that the ratio of second to first harmonic signals can be used in practical application.
   文章还就不同地形散射体对探测结果的影响进行了测量和分析，实验结果表明二次谐波与一次谐波信号比值标定技术对便携式二极管激光光学测量能够很好的满足实际应用的需要。
10. Coefficient of determination of average CR and the first harmonic CR in baseline and hyperemia conditions were greater than 0.97 ( P < 0.001).
    基础状态和充血状态的平均冠脉阻抗和一次谐波冠脉阻抗的决定系数（r2）均大于0.97（P<0.001）。
11. Fast Measuring First Harmonic Reactive Power in Power System Based on 8098 Single Chip Processor
    基于8098单片机的电网基波无功功率快速测量
12. In this paper, the curve-fitting method is used for fitting the measuring signal distinguishes and retains the first harmonic component;
    本文应用曲线拟合法对测量信号进行拟合，识别并保留了一次误差运动，正确消除了测量球的偏心，从而得到包含一次误差运动在内完整的误差运动。
13. Because "DGB-2 Type Fast Track Dynamic Power Factor Compensation Device" has detecting circuit of reaching zero, the paper first analysis the harmonic detecting of starting to sample at reaching zero time and realize the upper harmonic detecting.
    因为DGB&2型快速跟踪动态功率因数补偿装置具有过零检测电路。论文首先对过零时刻开始采样的谐波检测进行分析，实现了过零时刻开始采样的谐波检测。
14. The Duffing Eguation with large damping solved by using first harmonic balance method
    基波平衡法求解大阻尼Duffing方程
15. And gives the safety evaluation indexes of nodal diameter static frequency of first harmonic system vibration band of blades with round linking. All these have reference value for judging the high frequency vibration of blade system.
    给出了整圈连接叶片一阶系统带节径静频率的安全性评价指标，时判断叶片系统的高频振动具有参考价值。
16. The method uses the DC component and the first harmonic of a curve'S chain code expressed by fourier series to fit the curve, avoiding the inverse calculation of an array used in general methods.
    该方法利用闭合曲线的傅立叶级数表示的直流分量和一次分量实现对闭合曲线的椭圆拟合，可以避免通常椭圆拟合方法中的矩阵求逆问题。
17. Starting off with vortex tube theory, the relationship between the angular rates and the first harmonic inflow is deduced, and then the generalized model of main rotor dynamic inflow is modified.
    本文建立了尾迹弯曲的模型，推导出角速率与一次谐波入流分量之间的关系，据此对旋翼的广义动态入流模型进行了增广和修正；
18. After the nonlinear and absorption effect is taken into account in the applications where high power ultrasonic is involved, the first and second harmonic components of the sound field of stepped circular plate is analyzed, based on the KZK equation and quasi-linear condition.
    考虑到大功率超声应用中的非线性和吸收作用，本文从KZK方程和准线性条件出发，对于工作在共振频率下的这种阶梯圆盘，推导了它的一阶和二阶谐波声场计算方法。
19. In this paper, firstly, relations of first two harmonic induced velocities to the lower and same-order harmonic circulations are obtained from the generalized classical vortex theory of the rotor.
    本文从旋翼的广义经典涡流理论出发，通过环量对诱导速度的贡献的简化处理，推导出旋翼诱导速度的二阶分布。
20. The first order non-simple harmonic coefficient enhances modulus.
    第一非简谐系数的存在使弹性模量增大。
21. The first harmonic winding and harmonic winding no-load property curve are gained when field current is change.
    通过改变励磁电流的大小，得到了基波绕组和三次谐波绕组的空载特性曲线。
22. This article first harmonic harm, the causes, such as management standard simply introduces several different, and separately calculated method of harmonic described and compared.
    文章首先对谐波的产生原因、危害、管理标准等进行了简单的介绍，并分别对几种不同的谐波计算方法进行了阐述和比较。
23. The first harmonic measurement is achieved using analog filters, because the error is too large, real bad, harmonic measurement process is no longer the preferred method.
    最早的谐波测量是采用模拟滤波器实现的，由于误差太大，实时性太差，谐波测量过程中该方法已不再优先选用。
24. The utility of the ratio of second and first harmonic to eliminate the influent of light source fluctuation was analyzed.
    并对利用二次谐波与一次谐波的比值来消除由光源波动引起的影响等做了分析。
25. Secondly, the principles of the LLC half-bridge resonant converter are presented and the performance of LLC resonant converter is analyzed using FHA ( First Harmonic Approximation) method in detail.
    其次介绍了LLC半桥谐振变换器的工作原理，并采用基波分析的方法对电路的特性进行详细分析。
26. In fact, the radial composite deviations of master gears do exist and affect the accuracy of measurement results by the first harmonic.
    但实际上，标准齿轮的径向综合偏差是存在的，而且以一次谐波的形式传递给被测齿轮，影响其检测结果的准确性。
27. Harmonic analysis of angle measuring error has been done through Fourier analysis theory. First harmonic, second harmonic and third harmonic have been compensated with the method of software. Finally, measuring results have satisfied the specific requirements.
    利用傅立叶分析理论对测角系统的误差进行谐波分析，补偿一、二、三次谐波误差，得到补偿公式，通过软件方式实现误差补偿，最后使得测量结果满足技术指标要求。
28. More convenient using of fast Fourier transform to get the first harmonic of the mathematical model, and the error is relatively large.
    利用快速傅立叶变换比较方便得到一次谐波的数学模型，而且误差比较大。

noun

1. the lowest tone of a harmonic series

   Synonym:    fundamentalfundamental frequency