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1.
A phonetogram is a plot of the dynamic range of the voice as a function of fundamental frequency. Traditionally, the phonetogram only records the sound-pressure level (SPL) of the threshold of phonation and the upper limit in SPL the voice can reach with sustained phonation as a function of the fundamental frequency (F0). In this study, the phonetogram is extended by including acoustic voice-quality parameters. Three additional parameters are tested: jitter, shimmer, and crest factor. For each individual voice, the variation in the three parameters is evaluated over the entire phonetogram area. By averaging individual phonetograms, standard or norm phonetograms are obtained revealing general patterns in voice-quality variation. These patterns reflect the complex relations between F0, SPL, and the acoustic voice-quality parameters just mentioned. Jitter and shimmer distributions over the phonetogram show that large variations in perturbation values can be expected when production conditions are altered. Highest perturbation values are found for the low F0 and low SPL phonations. For all voices, a gradual decrease of the crest factor is found with increasing F0, reflecting the degrading of spectral complexity with F0. The crest-factor parameter can also be used to mark those areas in the phonetogram where the fundamental dominates the waveform and where flow control is the main SPL regulating mechanism in voice production. The strong quality variations within the phonetogram stress the need for accurate control of F0 and SPL in objective voice-quality measurement.  相似文献   

2.
Phonation threshold pressure has been defined as the minimum subglottalpressure to generate phonation. Previous research has indicated that children may habitually employ higher subglottal pressures than adults. In the present investigation sound pressure level (SPL) and subglottal pressures at different pitch levels were measured at and above phonation threshold in nine children. Phonation threshold values were scattered in reasonable agreement with Titzes' prediction, although a discrepancy was noted regarding the frequency dependence in some voices. At normal conversational loudness and loudest level of phonation the children's PS values were between two to four and four to eight times the predicted threshold values, respectively. At normal conversational loudness and habitual pitch subglottal pressures were lower than those previously observed for children, but similar to those found for female adults. The SPL in softest and loudest phonation were somewhat lower as compared to previous phonetogram data for children and for female adults. At normal loudness and habitual pitch the SPL values were similar to those of female adults. For a doubling of Ps mean SPL increased by 10.5 dB on the average.  相似文献   

3.
We report high resolution infrared absorption studies of rare gas (Rg) atom doped solid parahydrogen in the hydrogen S1(0) region around 4486 cm−1. At low Rg atom concentrations (∼0.1%), satellite transitions appear in the S1(0) region due to rovibrational excitation of parahydrogen molecules with one nearest-neighbor Rg atom. The Ne satellite feature differs qualitatively from the Ar, Kr, and Xe satellite features for reasons described within. The frequency of the S1(0) satellite features linearly shift to lower energy as the polarizability of the Rg atom increases while the absorption coefficients increase with the square of the Rg atom polarizability. Rotational calculations are performed for H2 with a nearest-neighbor Rg atom assuming a rigid hexagonal close-packed lattice structure. The calculated fine structure of the S1(0) satellite features agree qualitatively with lifting of the 2J+1 degeneracy of the v = 1, J = 2 upper state caused by the anisotropy in the Rg-H2 intermolecular potential. The discrepancy between the calculated and measured Rg atom S1(0) satellite features may signal partial delocalization of the J = 2 roton onto neighboring parahydrogen molecules.  相似文献   

4.
We show that every finitely additive state on the system F(S) of all orthogonally closed subspaces of an infinite-dimensional inner product space S attains all values from the real interval [0,1]. In particular, we show that there is no finitely additive countably-valued state on F(S) whenever dim S=. The main technique we use is an embedding of L(H n ) into F(S).  相似文献   

5.
The phonetogram has been recommended as an international tool for voice analysis. However, the capability of this technique to distinguish between different vocal groups has not been clearly established. The purpose of this study was to examine untrained versus trained vocalists using the phonetogram and the fundamental frequency by intensity (F0/SPL) information derived through that method. In this study, “musical” or “controlled” ranges of phonation were stressed rather than “physiological” ranges. Results indicated that (a) characteristic phonetographic profiles may be established for untrained versus trained vocalists, and (b) trained vocalists show significantly increased capability in terms of F0 range and maximum, minimum, and comfortable SPL production. Elicitation of “controlled” phonations may be the key to revealing the underlying vocal capabilities of seemingly different vocal groups.  相似文献   

6.
Muscle tension dysphonia (MTD) is a hyperfunctional voice disorder commonly seen in professional voice users. To date, published acoustic studies of this disorder have mainly focused on nontonal language speakers, and no publication has documented its impact on lexical tone characteristics. In this study, we examined whether and how this voice disorder affected acoustically and perceptually the characteristics of tones in Vietnamese teachers. Voice data were obtained from 42 Vietnamese female primary school teachers diagnosed with MTD and 30 vocally healthy teachers. Tonal data were analyzed using Computerized Speech Lab (CSL-4300B) and Speech Analyzer. Parameters analyzed included the two most important acoustic cues in Vietnamese tones, that is, tonal fundamental frequency (F0) and laryngealization. Tonal F0 was assessed using a factorial analysis of variance with group and career durations as independent variables. Tonal samples were also perceptually assessed by a panel of native speakers of the same dialect. The results showed that MTD lowered tonal F0 in high tones and tones with extensive fundamental frequency variation. There was also a significant main effect for career duration; in MTD group, tonal F0 was lower in teachers with longer career duration. The teachers with MTD showed different patterns of laryngealization compared with the control group. Tone perception was poorer for tones with extensive fundamental frequency variation and without a typical phonation type. The results in this group of teachers supported our hypothesis that MTD impairs lexical tone phonation.  相似文献   

7.
Yu Guo  Jinchuan Hou 《Physics letters. A》2011,375(7):1160-1162
Let ρS(H1H2) with dim(H1H2)=∞. Suppose that L:S(H1H2)→S(H1) is a map. It is asserted in [1] that if L satisfies the condition Tr(PL(ρ))=Tr((PI2)ρ) for all rank-one orthogonal projectors PB(H1), then L is given by L(ρ)=Tr2(ρ). However the proof in Blanchard and Bruning (2006) [1] is not correct. The purpose of this short Letter is to give a proof of this result.  相似文献   

8.
Fluorescence and excitation spectra of coronene vapor have been measured under different conditions. Weak emission which can be regarded as the fluorescence from the third excited singlet state, S3(1E1u), was observed in addition to the S1(1B2u) and S2(1B1u) fluorescence. The observed S2 and S3 fluorescence are substantially different from those reported previously for coronene vapor. Addition of oxygen resulted in significant decrease of the S1 fluorescence intensity, but did not affect the S2 fluorescence intensity, indicating the faster decay rate of the S2 state than that of S1. Excitation energy dependence of the S1, S2 and S3 fluorescence quantum yields (ΦF(S1), ΦF(S2) and ΦF(S3), respectively) revealed that ΦF(S1) decreases with increasing excitation energy, while ΦF(S2) and ΦF(S3) increase significantly. The quantum yield ratios, ΦF(S2)/ΦF(S1) and ΦF(S3)/ΦF(S2), obtained as a function of excitation energy are correlated with the ratios of the relative internal conversion rates.  相似文献   

9.
Stabilization characteristics of laminar lifted jet flames in a coflow were investigated experimentally to elucidate the effect of Schmidt number in methane and ethylene fuels diluted with N2, He, and Ar. A non-monotonic (decreasing and then increasing) liftoff height (HL) behavior with jet velocity (U0) was observed previously for methane fuel diluted with N2. To further elucidate the fuel Schmidt number (ScF) effect in exhibiting such a non-monotonic (U-shaped) behavior, various diluents (N2, He, and Ar) were added to the fuel streams and methane and/or ethylene fuels were used. The result showed three flame types in terms of ScF and fuel density; nozzle-attached flame, stationary lifted flame, and oscillating flame. Among stationary lifted flames, two distinct HL behaviors with U0 were observed; monotonic and non-monotonic HL behaviors. A critical Schmidt number (ScF,cr1) existed over which monotonically increasing behavior was observed. A second critical Schmidt number (ScF,cr2) also existed such that U-shaped behavior was observed for ScF,cr2<ScF<ScF,cr1. An oscillating lifted flame was observed for ScF<ScF,cr2. The oscillating and stationary lifted flames can be categorized in terms of the density differences among the fuel, air, and burnt gas. For the increasing HL cases (including the increasing regime in U-shaped behavior), HL behavior can be characterized in terms of ScF, the density difference between fuel and air, ScF,cr1, and U0. While the decreasing HL regime in the U-shaped behavior can be characterized with ScF and/or the Richardson number (defined based on the density difference between fuel and air). Oscillating flames were observed with the frequency range of 2.1–2.7 Hz by the repetitive action of positive (by burnt gas) and negative (when the fuel heavier than air) buoyancies.  相似文献   

10.
Measurements of the fluorescence intensity IF, excited by two-photon pumping, have been carried out in different dye solutions by utilizing a low power cw laser (IL ≈ 12 mW) and a particular experimental technique. A considerable departure from the quadratic law IFI2L with the varying of 2 - ΔEi quantity has been detected. This behaviour has bee n accounted for by considering the dependence of the non-linear and linear cross sections relative to the S0 → S1 and S0 → S2 transitions on the laser frequency.  相似文献   

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