查询词典 numerical signal

In the product design, uses modular, the parametrization 3D computer design system to carry on the modelling design, may personalize has custom-made, the image is lifelike, the effect is direct-viewing; On the production equipment, has provided the precise numerical control machinery, including the numerical control plate cutter, the numerical control knee bend machine, the numerical control key seating machine, the plasma cutter and so on, has the advanced working capacity; In the technical strength, has one batch of collection design, the manufacture, the installment is a body, experienced professionals.

在产品设计上，采用模块化、参数化的3D电脑设计系统进行造型设计，可以个性化定制，形象逼真，效果直观；在生产设备上，配备了精密的数控机械，其中有数控剪板机、数控折弯机、数控开槽机、等离子切割机等，具有先进的加工能力；在技术实力上，拥有一批集设计、制造、安装为一体，经验丰富的专业技术人员。

The results of our numerical simulation show that the numerical method applied in our paper is practical, the calculation results match the actual situation properly; the digital images from numerical simulation possess a positive significance in understanding and improving the heat flow distribution of the meat dry kiln. The proposed method provides a feasible approach to analyze and improve the flow field of meat dry kiln with numerical simulation.

数值计算的结果表明：本文所用的数值计算方法是可行的，基本符合实际情况；所得计算结果分析图像对了解干燥窑中流场的分布情况和如何改善干燥窑流场分布具有积极的参考意义，本文所提出的方法为采用数值计算方法分析改善干燥窑流场问题提供了一种可行的手段。

Combining the definition of CWT and the derivative property of convolution, we constructed a general method to calculate the approximate derivative of signal through CWT by using the first and second derivative of Gaussian function, Haar, and the first derivative of three-order-Spline function as wavelets. As compared with the other approaches of calculating derivative, which include the numerical differentiation, polynomial filters, Fourier transform, and the recently proposed DWT method, fast calculation and simple mathematical operation were remarkable advantages of CWT method. For the signal corrupted by severe noise (Signal-toNoise Ratio=5), the satisfactory results could also obtained via CWT method through appropriately adiusting the dilations.

在此基础上，(1)结合连续小波变换的特点和卷积的微分性质，提出了使用Gaussian函数的一阶和二阶导数，Haar和三次样条函数的一阶导数作为小波函数的连续小波变换计算信号近似导数的一般性方法，与其他导数计算方法(包括数字微分法，多项式滤波法，Fourier变换法和离散小波变换法)相比，本法简单便捷，计算速度快，对于噪声含量较高的信号(S/N为5)，只要适当调节尺度即可获得比较满意的结果。

Numerical calculation for sinusoidal signal, Gaussian periodic signal and square periodic signal is performed. The results show that zero-broadening slow and fast light is achieved using this optimized Brillouin comb gain for the three types of periodic signals, and the validity of the universal formula is proved.

通过对正弦信号、周期性高斯信号和周期性方波信号的数值计算，结果表明，利用该优化的梳状布里渊增益谱可实现这三种周期信号在零展宽下的快慢光，证实了所得普适公式的正确性。

The numerical analysis shows that the effect of an input sinusoidal signal is also a sinusoidal signal in the output, and the effect of the white noise is a Wiener process. When the system parameters are small enough, the effect of signal modulating noise can occur in the stochastic systems.

理论分析表明，正弦信号在系统输出中的数值表现仍为正弦信号，白噪声的效应是维纳过程，较小的系统参数才能使随机共振系统发生信号调制噪声效应。

By making a numerical analysis of the bistable stochastic dynamical systems, we find that the effect of an input sinusoidal signal is also a sinusoidal signal in the output, and the effect of the white noise is a Wiener process. When the system parameters are small enough, the coupling effect between the sinusoidal signal and the white noise can be largely weakened.

随机共振是双稳系统在周期信号和噪声的作用下表现出来的非线性现象，当系统的非线性与信号和噪声之间存在某种匹配时，通过对系统施加适当强度的噪声，可以提高系统对信号的响应，系统输出的信噪比对噪声强度表现出一峰状曲线[11] 。

The time-history velocity response signal of pile can be decomposed by Sym wavelet. The power spectrum value can be extracted from some specified spectrum range. These values from one signal makes up the characteristic vector representing this signal. The relationship between characteristic vector of pile and pile defect type can he established by using BP artificial neural network. Abundant time-history velocity response signals of pile can be acquired by numerical simulation method.

利用Sym小波对基桩速度响应时程曲线进行小波分解，对指定频带上的信号分量进行特征值提取，提取的特征值为反映各频带范围内体现能量分布的功率谱均值，提取的特征值可构成反映信号特征的特征向量，同时利用BP人工神经网络的非线性映射特性建立特征向量和基桩缺陷类别之间的一种对应关系。

Extract information based on the instantaneous features : In the center is one of the instantaneous rate of the power spectral density of the maximum, is a center to the absolute value of the instantaneous rate of the standard deviation, Non-zero weak signal instantaneous phase of the nonlinear component absolute standard deviation, Non-zero weak signal instantaneous phase of the nonlinear component standard deviation, In the center is one of the non-weak signal of the absolute value of the instantaneous frequency standard deviation, a signal to one of the instantaneous frequency of the power spectral density of the maximum, According to 16QAM and QPSK signals XI axis projection in the different performance parameters raised.

提取信号七个基于瞬时信息的特征：零中心归一化瞬时幅度功率谱密度的最大值，零中心归一化瞬时幅度绝对值的标准偏差，零中心非弱信号段瞬时相位非线性分量绝对值标准偏差，零中心非弱信号段瞬时相位非线性分量标准偏差，零中心归一化的非弱信号段瞬时频率绝对值的标准偏差，一个信号段的归一化瞬时频率功率谱密度的最大值，根据信号 QPSK 和16QAM在 XI 轴投影的不同表现，提出特征参数。

Then the digital audio signal is set into segments and DWT is performed. Finally the modulated signal is embedded in the coefficients with relatively large absolute value on middle frequency range detail signal adaptively. The original digital audio signal is necessary when detecting the watermark.

在应用扩频技术的算法中，首先将视觉上可辨的二值水印图像降维为一维序列，再将一维水印序列伪随机排序并与m序列作扩频调制，最后对数字音频信号进行分段离散小波变换，把经过调制的水印信息自适应地嵌入到原音频信号小波分解中等尺度绝对值较大的分量上。

But, in the natural and artificial signal, a lot of signal phases don\'tvary linearly with time, for example, we usually use chirp signal in the radar technology,frequency step signal, linear modulation component of the ground echo in the SARtechnology, linear modulation component of the moving target echo, linear modulationcomponent while the airborn radar detecting the moving target, etc.

在自然界和人工信号中，许多信号的相位变化并不是随时间一次方变化，如雷达技术中常用的线性调频信号，频率步进信号，另外，SAR 技术中，地面回波所含有的线性调频分量，ISAR技术中，运动目标的回波所含有的线性调频分量，机载雷达探测运动目标时的线性调频分量，等等；傅里叶变换对此类信号分析所得的结果是信号在不同频率点上的能量分布，即信号在基函数上的投影。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。