首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5篇
  免费   4篇
数学   1篇
物理学   8篇
  2018年   1篇
  2014年   1篇
  2010年   1篇
  2009年   1篇
  2007年   2篇
  2004年   2篇
  1996年   1篇
排序方式: 共有9条查询结果,搜索用时 15 毫秒
1
1.
Measures of cepstral peak prominence, using the smoothing algorithm and linear regression analysis software developed by Hillenbrand, have been shown to be reliable predictors of dysphonia in voice samples.(1-4) Recently, the Computerized Speech Laboratory [(CSL) Kay Elemetrics, Pinebrook, New Jersey] has introduced cepstral analysis as a component of that software package. The cepstral peak, in this instance, is calculated by the voice clinician analyzing the phonatory sample by subtracting the value of the peak from the apparent baseline signal. This study compares the ability of cepstral peak values calculated from the CSL software to predict dysphonia reliably with that of the values produced by the smoothing algorithm and linear regression analysis of Hillenbrand. The results of this study show that linear regression analysis is an important step in calculating the cepstral peak prominence, thus limiting the usefulness of software programs that do not employ this step.  相似文献   
2.
肖寒春  郭俊峰  张丽 《应用声学》2018,37(6):909-915
梅尔倒谱系数特征提取技术依据人耳的感知特性将声信号从线性频域转换到梅尔域,在语音识别中得到广泛应用。该文将梅尔倒谱系数技术用于小型低空飞行器的声信号特征提取中,并针对螺旋桨驱动类的小型低空飞行器具有稳定的强谐波特性,对梅尔倒谱系数特征提取中使用的梅尔滤波器进行改进,通过对此类谐波处的线性频谱与梅尔谱转换曲线的斜率进行投影替换,提高滤波器对该谐波处信号的感知敏感度。仿真结果表明,使用改进的梅尔倒谱系数特征提取方法对小型低空飞行器进行特征提取时,能够得到更低的等误识率,并且在低信噪比环境中,改进的梅尔倒谱系数特征提取方法具有更好的抗噪能力。  相似文献   
3.
In this paper we present a new wavelet-based algorithm for low-cost computation of the cepstrum. It can be used for real time precise pitch determination in automatic speech and speaker recognition systems. Many wavelet families are examined to determine the one that works best. The results confirm the efficacy and accuracy of the proposed technique for pitch extraction.  相似文献   
4.
5.
基于频域幅度谱数据重建电磁脉冲时域波形   总被引:6,自引:3,他引:6       下载免费PDF全文
 由频域幅度谱数据重建时域脉冲波形,是电磁脉冲效应及传感器标定研究中经常遇到的问题。根据最小相位原理,利用倒谱技术,编程实现了从频域幅度谱数据构造相位信息,进而反演时域脉冲响应波形。对几类函数波形和一组实测高空核爆电磁脉冲(HEMP)波形的验证结果表明,HEMP波形、余(正)弦阻尼振荡波形等信号的重建波形与原始波形符合很好。对于非最小相位信号,重建波形的前(后)沿、峰值等细节参数有一定差别,但也能给出一些波形、累积能量、幅值量级等方面的标志信息。  相似文献   
6.
We investigated speaking fundamental frequency and periodicity of voicing during conversational speech in a 105-year-old woman. Analyses revealed higher mean speaking fundamental frequency compared to previously published data obtained from elderly women. In the absence of normative data, the results of cepstrum analyses performed on vowels produced during connected speech revealed less periodicity for the 105-year-old woman's voice than for a 35-year-old woman's voice. The main finding of this study indicates that previously reported group trends regarding aging effects on mean speaking fundamental frequency of the female voice cannot simply be attributed to all elderly individuals. These results stress the importance, for clinical and research purposes, of recognizing the existence of considerable intra- as well as intersubject variability in the effects of aging on the voice.  相似文献   
7.
Generally, ultrasonic method and an elastic impact wave method are mentioned as examples representing the nondestructive test method. However, the ultrasonic method is known for the investigation of shallow depth becoming very shallow because of its small input. And the elastic impact wave method uses for example, a hammer for the discrimination of the reflection wave produced by minute cracks existing in the object, which is difficult. Theoretically, if it becomes possible to input the vibration of an ultrasonic domain into artificial structures such as a concrete and a boulder with strong amplitude, deeper investigation of depth and higher precision will be attained. The authors have developed a new ultrasonic method by using ultrasonic wave of the chirp signal, using the input of this system and using auto correlation and cepstrum as the analysis methods. In this paper, the experiment is classified into Pattern 1 and Pattern 2. In Pattern 1, the experiment of receiving the reflection wave was carried out using the concrete block with a width of 1300 mm and the down chirp signal from 50 kHz to 40 kHz. In Pattern 1, a reflection wave was clearly detected, and the length of the concrete block was calculated using auto correlation analysis, and was obtained as 1311.76 mm. In Pattern 2, the experiment of receiving the reflection wave was carried out using the same concrete block and the down chirp signal from 150 kHz to 130 kHz. In Pattern 2, the direct wave and the reflection wave were mixed, therefore it was not possible to presume the length from the obtained waveform. So cepstrum analysis method was used, and the traveling time of the reflection wave was obtained. In this result, the length of the concrete block was given as 1278.25 mm.  相似文献   
8.
基于线性预测倒谱的被动声纳目标特征提取技术   总被引:1,自引:0,他引:1       下载免费PDF全文
柳革命  孙超  刘兵 《应用声学》2007,26(5):277-281
从声纳员的角度出发,被动声纳目标可以被看作为一个发声体,利用线性预测倒谱从声纳目标噪声中分离出目标作为发声体的冲激响应在倒谱域中的表示,提取一组识别特征,设计神经网络分类器,对三类目标进行分类。实测数据验证了基于线性预测倒谱的被动声纳目标特征提取方法是可行的。  相似文献   
9.
赵毅  尹雪飞  陈克安 《应用声学》2010,29(6):416-424
共振峰频率是语音信号的一个重要参数。传统的基于线性预测的共振峰检测算法由于受到计算量的限制,很难实现实时处理。本文提出一种基于倒谱变换的共振峰频率检测算法,采用后置处理,比较声道冲击响应对数幅频特性的二次导数和相频特性一次导数检测出的结果,删除伪峰数值和甄别合并共振峰,提高检测精度。仿真结果证明,该算法计算效率高,低信噪比下仍能保持较好的检测性能。  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号