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1)  point power spectrum density
点功率谱密度
2)  power spectrum density
功率谱密度
1.
TAM method of analyzing power spectrum density of heavy-tailed ON/OFF Source;
分析重尾ON/OFF源功率谱密度的TAM近似法
2.
In this system,the characteristics of monitoring signals are extracted by the method of power spectrum density maximum(PSM),and least square support vector machine(LS-SVM) is proposed to detect damages.
基于被动监测技术的局限性,搭建了损伤主动监测系统,对监测信号进行了功率谱密度最大值(PSM)特征提取,并提出了一种基于最小二乘支持向量机(LS-SVM)的损伤检测方法。
3.
The online measuring of the ground surface roughness was estimated by taking into account the power spectrum density of the frictioninduced acoustic emission.
利用摩擦产生的声发射(AE)信号的功率谱密度对磨削表面粗糙度进行在线评价。
3)  power spectral density
功率谱密度
1.
Study and validation of the relationship between international roughness index and power spectral density;
国际平整度指数与路面功率谱密度相关关系研究及验证
2.
Specifying surface roughness of optical film substrate using the power spectral density;
利用功率谱密度函数表征光学薄膜基底表面粗糙度
3.
Power spectral density measurement for large aspheric surfaces;
用于大口径非球面的波前功率谱密度检测
4)  PSD
功率谱密度
1.
MATLAB numerical simulation of stationary stochastic porcess based on ISTA PSD;
基于ISTA功率谱密度的MATLAB随机过程时域样本再现
2.
Pulse Shape of UWB Signals and PSD Analysis;
UWB信号波形及功率谱密度的分析
3.
The track spectra of Qinhuandao-Shenyang(QS) passenger railway line and German railways were compared in terms of power spectrum density(PSD),amplitude of time domain samples and dynamic performance.
从轨道谱的功率谱密度、时间样本幅值及对动力学性能影响的角度,对比了秦沈线轨道谱和德国轨道谱。
5)  power spectrum density(PSD)
功率谱密度
1.
With its attacking traffic pattern,obvious difference was found between the power spectrum density(PSD) of legitimate and attack traffic samples.
分析发现,合法流量和包含攻击包流量采样在功率谱密度上存在显著差异。
2.
Directed against the situation of difficult to estimate the vibration fatigue life-span under complex random loading in engineering practice,the estimation of fatigue life-span on the viabrational component parts under random loading has been carried out based on Power Spectrum Density(PSD) function.
针对工程实践中复杂随机载荷下振动疲劳寿命难估算的情况,基于功率谱密度函数(PSD)对随机载荷下的振动构件进行疲劳寿命估算,分别讨论了窄带随机载荷和宽带随机载荷两种情况,方法简单,具有很强的工程实用性。
6)  power spectral density(PSD)
功率谱密度
1.
The Short Time Fourier Transform(STFT) is utilized to estimate the power spectral density(PSD)of the tunneling-current signals and the data s feature vector was extracted in the frequency space.
针对STM采集的信号,运用短时傅立叶变换对其波形数据进行功率谱密度估计,对信号在频率域中的特征向量加以提取。
2.
Transmitted reference ultra-wide band(TR-UWB) system is introduced,and the power spectral density(PSD) of conventional single user TR-UWB signals presented.
介绍了传输参考超宽带(TR-UWB)系统,给出了传统单用户TR-UWB信号的功率谱密度(PSD);针对多用户情况下的TR-UWB信号,结合数学模型,给出了TR TH-PPM和TR TH-PAM信号功率谱密度的数学表达式。
3.
Based on random vibration theory,an iteration approach has been adopted to calculate the acceleration power spectral density(PSD) corresponding to design response spectrum curve of the GB50011-2001.
回顾了地震地面加速度随机过程模型,根据随机振动理论采用迭代方法求解出与我国现行《建筑抗震设计规范》(GB50011-2001)设计反应谱相对应的功率谱密度函数,选用胡聿贤功率谱密度函数拟合上述功率谱密度函数,运用非线性拟合技术给出了与规范对应的胡聿贤功率谱参数,可供这种模型作为地震地面运动输入时选用。
补充资料:功率谱密度估计
      随机信号的功率谱密度用来描述信号的能量特征随频率的变化关系。功率谱密度简称为功率谱,是自相关函数的傅里叶变换。对功率谱密度的估计又称功率谱估计。平稳随机信号x(t)的(自)功率谱Sxx(ω)定义为
  
  
  (1)
  式中rxx(τ)为平稳随机信号的自相关函数。
  
  对于离散情况,功率谱表示为
  
  
  (2)
  式中T为离散随机信号的抽样间隔时间。
  
  当利用随机信号的 N个抽样值来计算其自相关估值时,即可得到功率谱估计为
   (3)
  可见,随机信号的功率谱与自相关函数互为傅里叶变换的关系,这两个函数分别从频率域和时间域来表征随机信号的基本特征。按上式计算功率谱估值,其运算量往往很大,通常采用快速傅里叶变换算法,以减少运算次数。
  
  计算信号功率谱的方法可以分为两类:一为线性估计方法,有自相关估计、自协方差法及周期图法等。另一类为非线性估计方法,有最大似然法、最大熵法等。线性估计方法是有偏的谱估计方法,谱分辨率随数据长度的增加而提高。非线性估计方法大多是无偏的谱估计方法,可以获得高的谱分辨率。
  
  

参考书目
   何振亚:《数字信号处理的理论与应用》,人民邮电出版社,北京,1983。
   A. V. Oppenheim, R. W. Schafer, Digital Signal Processing Prentice-Hall, Inc., Englewood Cliffs,New Jersey,1975.
  

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