要计算反正弦的表达式。
这种偏离完全正弦的畸变称为电压、电流波形的谐波畸变。
This deviation from perfect sinusoids is usually expressed in terms of harmonics distortion of the voltage and current waveforms.
通过分析得到整个电机电磁场的分布及波形近似为正弦的气隙磁感应强度，分析结果有助于对电机进行优化设计和控制。
A approximately sine waveform air-gap magnetic field density can be gained based on the analysis of the whole electromagnetic field. The results are helpful to optimization design and control.
一些人需要复习一点数学课程，正弦的作用是给出在一个直角三角形中的一个已知角所对应的一条边与直角三角形斜边之间的比率。
For anyone that needs a little refresher course, the sine function gives the ratio of the opposite side of a given Angle in a right triangle to the hypotenuse.
PWM整流器可实现正弦的网侧电流、单位或可调的功率因数、能量的双向流动，是一种真正意义上的“绿色环保”电力电子装置。
The PWM rectifier is a "green" power electronics equipment since it offers sinusoidal input currents, unity or adjustable power factor, reversal of power flow.
本文对于反电动势波形接近正弦的永磁无刷直流电动机，提出一种基于六个离散位置信号的自同步svpwm控制方法，用于抑制电磁转矩脉动。
For the BLDCM which has a sinusoidal back EMF, this paper presents a self-synchronous SVPWM control method using six discrete position signals for minimizing torque ripple.
在此基础上进一步结合实验模型，这个数字模型被用于分析正弦地形上的近岸流在波浪作用下的分布情况。
Combined with the lab experiment, the numerical model is applied to wave-induced nearshore currents on a fixed tri-cuspate beach.
现在，假设您想进行一些简单的处理，比如写出这些角度的正弦值。
Now, suppose you want to do something as simple as write out the sines of those angles.
例如，清单3展示了一个样式表，它生成角度的正弦、余弦和正切值。
For example, Listing 3 shows a stylesheet that generates sines, cosines, and tangents for the angles.
此外，一个粗略的正弦曲线图表可以在每天或每年的平均每日温度平面图表中看到，虽然这个图形可能和倒置的余弦波看起来很像。
Also, a rough sinusoidal pattern can be seen in plotting average daily temperatures for each day of the year, although the graph may resemble an inverted cosine wave.
正弦波形赋予了通过水道的结构轮廓的形状。
A sinusoidal waveform provides the structural silhouette shape across the channel.
在提示符中输入plotsin (x)：您应该在弹出窗口中看到熟悉的正弦曲线。
Type in plot sin (x) at the prompt: you should see the familiar sine curve in a pop-up window.
下面是简单说明的multiplot，它绘制正弦、余弦及其各自倒数的曲线图。
Here is a simple annotated multiplot that plots the sine, cosine, and their respective reciprocals.
使用的最后一个命令reset对于绘制正弦曲线不是必要的。
The last command used, reset, is strictly not necessary for plotting the sine curve.
点P，速度向量,垂直于直线，所以该角的正弦值为。
Well, at point P, the velocity vector QP is perpendicular to the line QP, 1 so the sine of that angle is one.
说到如何用图像表示声音，大多数人都会想起与音量有关的正弦曲线。
When we think about how to represent sound visually, most of us probably picture those volume-dependent sine waves.
这就是以上的SAI原理中提到的正弦波浪线。
我们使用简单的正弦波模式作为一个简单原创的网页设计和创建单页布局的基础。
We used a simple sine wave pattern as the basis for a simple and original Web design and create a single-page layout.
例如，让我们考虑一下正弦波，也即正弦曲线这样一个描述平稳反复振荡的数学函数。
For instance, let's consider the sine wave, or sinusoid, a mathematical function that describes a smooth repetitive oscillation.
泰勒级数的效率也无法与现代桌面芯片的内置正弦函数相比。
The Taylor series is also inefficient compared to the built-in sine function of a modern desktop chip.
好的，让我们试着把等式，带入正弦函数，或者余弦数来做，你喜欢哪个都行。
All right. Let's try to substitute in that equation a sinusoid's or a cosine solution, whichever one you prefer.
一个能很好地展示这类表单用途的例子是如下所示的这个简单的正弦计算器。
The example that best illustrates the use of such forms is a simple sine calculator.
要准确快速地计算正弦函数和其他函数，需要非常仔细的算法，专门用于避免无意地将小的误差变成大的错误。
Proper calculations of sine and other functions that are both accurate and fast require very careful algorithms designed to avoid accidentally turning small errors into large ones.
这是我们正在采用的一种类似正弦曲线一样的工作方式。
在过去十八年的每个月中，马西博士都会接受恒星“55Cancri A”发出的讯号。逐渐地，“正弦波”曲线出现明显的分离。
Every month for the past 18 years, he has tuned in to the signal coming from 55 Cancri A. Gradually, the separate sine waves have become visible.
执行CPU高消耗的任务——100万次sine(正弦)和加法操作。
Performing a CPU Intensive Task - 1,000,000 sine and sum operations.
谐波是理想电波或正弦电波的变形。
Harmonics are deformations to the ideal electrical wave or sine wave.
这个特定的半正弦脉冲对实际情况来说只是一个非常近似的模型。
This particular half-sine pulse is only a very approximate model for the actual state of affairs .
所得到的系统对阶跃输入，斜坡输入，正弦函数输入有很好的响应特性。
The system has obtained very good step response, ramp response and sine function response.
这个效应可以在时间域通过观测电压的衰变率来测量，也可以在频率域通过正弦电流和电压之间的相变来测量。
This effect can be measured in either the time domain by observing the rate of decay of voltage or in the frequency domain by measuring phase shifts between sinusoidal currents and voltages.
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