共查询到20条相似文献,搜索用时 15 毫秒
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The categorization of voice into quality type (ie, normal, breathy, hoarse, rough) is often a traditional part of the voice diagnostic. The goal of this study was to assess the contributions of various time and spectral-based acoustic measures to the categorization of voice type for a diverse sample of voices collected from both functionally dysphonic (breathy, hoarse, and rough) (n=83) and normal women (n=51). Before acoustic analyses, 12 judges rated all voice samples for voice quality type. Discriminant analysis, using the modal rating of voice type as the dependent variable, produced a 5-variable model (comprising time and spectral-based measures) that correctly classified voice type with 79.9% accuracy (74.6% classification accuracy on cross-validation). Voice type classification was achieved based on two significant discriminant functions, interpreted as reflecting measures related to "Phonatory Instability" and "F(0) Characteristics." A cepstrum-based measure (CPP/EXP ratio) consistently emerged as a significant factor in predicting voice type; however, variables such as shimmer (RMS dB) and a measure of low- vs. high-frequency spectral energy (the Discrete Fourier Transformation ratio) also added substantially to the accurate profiling and prediction of voice type. The results are interpreted and discussed with respect to the key acoustic characteristics that contributed to the identification of specific voice types, and the value of identifying a subset of time and spectral-based acoustic measures that appear sensitive to a perceptually diverse set of dysphonic voices. 相似文献
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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
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Yolanda D. Heman-Ackah MD Deirdre D. Michael George S. Goding Jr. 《Journal of voice》2002,16(1):20-27
Traditional measures of dysphonia vary in their reliability and in their correlations with perceptions of grade. Measurements of cepstral peak prominence (CPP) have been shown to correlate well with perceptions of breathiness. Because it is a measure of periodicity, CPP should also predict roughness. The ability of CPP and other acoustic measures to predict overall dysphonia and the subcategories of breathiness and roughness in pathological voice samples is explored. Preoperative and postoperative speech samples from 19 patients with unilateral recurrent laryngeal nerve paralysis who underwent operative intervention were analyzed by trained listeners and by measures of smoothed CPP (CPPS), noise-to-harmonic ratio (NHR), amplitude perturbation quotient (APQ), relative average perturbation (RAP), and smoothed pitch perturbation quotient (sPPQ). The data were analyzed with bivariate Pearson correlation statistics. Grade of dysphonia and breathiness ratings correlated better with measurements of CPPS than with the other measures. CPPS from samples of connected speech (CPPS-s) best predicted overall dysphonia. None of the measures were useful in predicting roughness. 相似文献
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We present a method for the estimation of defect (trap) physical parameters from thermoluminescence (TL) glow peaks. In this method, the order of kinetics b is determined using two values of TL intensity each of which corresponds to the same temperature (T 1) on two separate glow peaks of a phosphor. The two glow peaks are obtained from two aliquots of the phosphor irradiated to same dose but read out at different heating rates. The proposed method requires a minimum of only two data points in contrast to standard peak shape (PS) methods that require three points corresponding to three different temperatures on the same glow peak. Once the order of kinetics b is determined, the activation energy E is calculated by taking a second point (T 2) on any one of the two glow peaks. The values of b and E thus obtained are used to evaluate the frequency factor S ′′ and the number of trapped electrons before the heating begins n o. The validity of the method was checked using two numerically generated glow peaks. For the two cases, the method reproduced the input values reasonably well. The method was also used to analyse two experimental glow peaks. The results obtained provide a reasonably good fit to the experimental data. The kinetic parameters calculated using the present technique are comparable to those calculated using PS and initial rise methods. Initial guesses can easily be obtained for E and S ′′ using the present technique when a glow curve is to be deconvoluted with a model consisting of many unknown parameters with E and S″ inclusive. 相似文献
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Vocal warmup is generally accepted as vital for singing performance. However, only a limited number of studies have evaluated this effect quantitatively. In this study, we evaluated the effect of vocal warmup on voice production, among young female singers, using a set of acoustic parameters. Warmup reduced frequency-perturbation (p < 0.001) and amplitude-perturbation values (p < 0.05). In addition, warmup increased singer's formant amplitude (p < 0.05) and improved noise-to-harmonic ratio (p < 0.05). Tone-matching accuracy, however, was not affected by warmup. The effect of vocal warmup on frequency-perturbation parameters was more evident among mezzo-soprano singers than it was among soprano singers. It was also more evident in the low pitch-range than in the higher pitch-ranges (p < 0.05). The results of this study provide valid support for the advantageous effect of vocal warmup on voice quality and present acoustic analysis as a valuable and sensitive tool for quantifying this effect. 相似文献
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平行因子分析法在太湖水体三维荧光峰比值分析中的应用 总被引:5,自引:0,他引:5
以太湖水样三维荧光光谱数据为例,提出在采用平行因子分析法(PARAFAC)处理后的荧光数据中提取荧光峰强度计算荧光峰比值进行水环境分析评价的方法,较直接在水样原始荧光谱图中获取的荧光峰强度更加准确客观。天然水体中各水样间由于受荧光团复杂多样性等因素的影响,某类荧光物质荧光峰的激发发射波长位置并不是固定不变的,就同一水样而言各类荧光峰之间的相互重叠干扰也将影响到荧光峰强度和位置的准确判断。而在PARAFAC模型各因子中提取相应荧光峰值可以保证各水样间同类荧光物质荧光峰在同一位置又有效减弱同一水样中各类荧光物质荧光峰之间的相互干扰,更加高效准确的利用荧光峰比值进行水环境分析。区域差异性分析时水样因子得分比值的区域变化与原始荧光峰比值变化趋势是一致的。 相似文献
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XPS peak shape analysis is used as a novel and nondestructive method to study Au nano-cluster growth mechanism on polystyrene (PS) as a function of deposition as well as diffusion and distribution of the nano-clusters in PS as a function of subsequent annealing at temperatures in the range from room temperature to above the glass transition temperature of PS. The Au nano-cluster size and density are determined for four different amounts of Au deposition. It is shown that this nondestructive method can give all mentioned information on such a metalized polymer without the need for any other complimentary and time consuming technique such as AFM, TEM and the destructive technique XTEM. Thus this method is suitable to monitor and control the degree of intermixing of metal nano-clusters and polymers which is of high technological interest. 相似文献
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Olaf Kster Bernd Marx Peter Gemmar Markus M. Hess Hermann Josef Künzel 《Journal of voice》1999,13(3):355-374
High-speed filming is one of the most informative methods for assessing voice physiology data. Tracing high-speed images of the glottis provides quantitative parameters such as the glottal area and the glottal width function. By way of example, a number of studies are discussed which extract quantitative data from high-speed images showing voice onsets. Furthermore, a new computer system (MVAS; multi-dimensional voice analysis system) is presented that synchronously displays a laryngoscopic high-speed film, the electroglottographical signal, and several acoustic analyses of the recorded voice sample. The automatic measurement of glottal width and glottal area from the laryngoscopic images is also provided. Looking at former studies and our analyses of voice onsets reveals a tremendous intersubject and even intrasubject variability (different prephonatory closure, different time span until full amplitude is reached, different open quotient). 相似文献
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Spectral Moments of the Long-term Average Spectrum: Sensitive Indices of Voice Change After Therapy? 总被引:1,自引:0,他引:1
Voice clinicians require an objective, reliable, and relatively automatic method to assess voice change after medical, surgical, or behavioral intervention. This measure must be sensitive to a variety of voice qualities and severities, and preferably should reflect voice in continuous speech. The long-term average spectrum (LTAS) is a fast Fourier transform-generated power spectrum whose properties can be compared with a Gaussian bell curve using spectral moments analysis. Four spectral moments describe features of the LTAS: Spectral mean (Moment 1) and standard deviation (Moment 2) represent the spectrum's central tendency and dispersion, respectively. Skewness (based on Moment 3) and kurtosis (based on Moment 4) represent the spectrum's tilt and peakedness, respectively. To examine whether the first four spectral moments of the LTAS were sensitive to perceived voice improvement after voice therapy, this investigation compared pretreatment and posttreatment voice samples of 93 patients with functional dysphonia using spectral moments analysis. Inspection of the results revealed that spectral mean and standard deviation lowered significantly with perceived voice improvement after successful behavioral management (p < 0.001). However, changes in skewness and kurtosis were not significant. Furthermore, lowering of the spectral mean uniquely accounted for approximately 14% of the variance in the pretreatment to posttreatment changes observed in perceptual ratings of voice severity (p < 0.001), indicating that spectral mean (ie, Moment 1) of the LTAS may be one acoustic marker sensitive to improvement in dysphonia severity. 相似文献
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Reinhardt Heuer Carol Towne Neil E. Hockstein Deborah Feij Andrade Robert Thayer Sataloff 《Journal of voice》2000,14(2)
The science of voice evaluation and assessment has profited from technological advancement and objective measurement of voice parameters has become an integral part of the voice examination, however, subjective voice evaluation remains a vital component of any voice examination. The Towne-Heuer Reading Passage was developed in 1970 to provide a reading sample that would facilitate subjective voice evaluation. The reliability of the passage was established using three judges listening to 15 normal Philadelphia speakers and 15 vocal abuse-misuse clients with verified vocal nodules. The frequency of hard glottal attack (HGA) was determined for the two groups and high interjudge and intrajudge correlation was found. A difference in the frequency of HGA was found between the two groups. 相似文献
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Dr. C. William Thorpe Stephen J. Cala Janice Chapman Pamela J. Davis 《Journal of voice》2001,15(1):86-104
Recordings of the rib cage and abdominal motions and acoustic output were obtained from five professional opera singers during performance of an aria recorded with two levels of voice projection. The condition of greater projection resulted in a significant increase in the acoustic power in the frequency band 2-4 kHz, relative to the power in the 0-2 kHz band, and a decrease in the mean expiratory flow, implying a move to more efficient vocalization with the greater projection. Also, the condition of greater projection resulted in a larger rib cage, particularly in the lateral dimension, but only a small decrease in the abdominal lateral dimension, suggesting that the greater abdominal support required for a larger projection is obtained by increased activation of abdominal muscles acting medially. 相似文献