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1.
Vocalization and breathing were studied in 40 healthy young children,including 5 boys and 5 girls at each, of ages of 18, 24, 30, and 36 months. A variable inductance plethysmograph was used to obtain estimates of volume changes of the rib cage, abdomen, and lung, as well as estimates of selected temporal features of the breathing cycle. Results indicated that breathing behavior was influenced by height and age, but not by vocalization type or sex. Such behavior was found to be highly variable, demonstrating that these young children had multiple degrees of freedom of performance available to accomplish the aeromechanical drive required.  相似文献   

2.
We present a general procedure for automatic quantitation of a series of spectral peaks based on principal component analysis (PCA). PCA has been previously used for spectral quantitation of a single resonant peak of constant shape but variable amplitude. Here we extend this procedure to estimate all of the peak parameters: amplitude, position (frequency), phase and linewidth. The procedure consists of a series of iterative steps in which the estimates of position and phase from one stage of iteration are used to correct the spectra prior to the next stage. The process is convergent to a stable result, typically in less than 5 iterations. If desired, remaining linewidth variations can then be corrected. Correction of (typically) unwanted variations of these types is important not only for direct peak quantitation, but also as a preprocessing step for spectral data prior to application of pattern recognition/classification techniques. The procedure is demonstrated on simulated data and on a set of 992 (31)P NMR in vivo spectra taken from a kinetic study of rat muscle energetics. The proposed procedure is robust, makes very limited assumptions about the lineshape, and performs well with data of low signal-to-noise ratio.  相似文献   

3.
Respiratory abdominal movements associated with vocalization were recorded in awake squirrel monkeys. Several call types, such as peeping, trilling, cackling, and err-chucks, were accompanied by large vocalization-correlated respiratory movements (VCRM) that started before vocalization. During purring, in contrast, only small VCRM were recorded that started later after vocal onset. VCRM during trill calls, a vocalization type with repetitive frequency modulation, showed a modulation in the rhythm of the frequency changes. A correlation with amplitude modulation was also present, but more variable. As high frequencies need a higher lung pressure for production than low frequencies, the modulation of VCRM seems to serve to optimize the lung pressure in relation to the vocalization frequency. The modulation, furthermore, may act as a mechanism to produce different trill variants. During err-chucks and staccato peeps, which show a large amplitude modulation, a nonmodulated VCRM occurred. This indicates the existence of a laryngeal amplitude-controlling mechanism that is independent from respiration.  相似文献   

4.
Electrical stimulation of the midbrain was used to elicit a variety of vocalizations from six anesthetized dogs. This study was conducted to investigate the ranges of and relationships between fundamental frequency of the vocalizations (F0) and tracheal pressure (Pt) produced during the vocalizations. The vocalizations were described according to type (growl, howl, and whine); F0 and Pt, as well as patterns of laryngeal muscle activity, were examined for each vocalization type. Natural-sounding growl and howl vocalizations were elicited from five dogs; three dogs also produced whines. With few exceptions, F0 was categorically different for the three vocalization types (low for growls, average for howls, very high for whines). Pt values overlapped for the three vocalization types, although, on average, howls were produced with greater Pt than growls. Patterns and degrees of laryngeal muscle activity varied across and within vocalization types, but general findings were consistent with the presumed function of most of the muscles. Laryngeal muscle activity may help explain some of the variability in the acoustic and aerodynamic data.  相似文献   

5.
Surface behavior and concurrent underwater vocalizations were recorded for Pacific white-sided dolphins in the Southern California Bight (SCB) over multiple field seasons spanning 3 years. Clicks, click trains, and pulsed calls were counted and classified based on acoustic measurements, leading to the identification of 19 key call features used for analysis. Kruskal-Wallis tests indicated that call features differ significantly across behavioral categories. Previous work had discovered two distinctive click Types (A and B), which may correspond to known subpopulations of Pacific white-side dolphins in the Southern California Bight; this study revealed that animals producing these different click types also differ in both their behavior and vocalization patterns. Click Type A groups were predominantly observed slow traveling and milling, with little daytime foraging, while click Type B groups were observed traveling and foraging. These behavioral differences may be characteristic of niche partitioning by overlapping populations; coupled with differences in vocalization patterns, they may signify that these subpopulations are cryptic species. Finally, random forest decision trees were used to classify behavior based on vocalization data, with rates of correct classification up to 86%, demonstrating the potential for the use of vocalization patterns to predict behavior.  相似文献   

6.
The spatial dynamics of laser beams in absorbing planar waveguides with a parabolic index profile in a saturable or cubic-quintic medium are calculated using the “collective variable approach” technique. In the absence of losses, we construct diagrams which define regions of self-focusing and self-diffractive beam propagation for both types of media. It is found that propagating pulses exhibit an oscillatory pattern, similar to breathing behavior in homogeneous media. If the incident pulse spatial profile and the center of the index profile are not aligned, the pulse oscillates around the index origin with a “beat” frequency that depends on the graded index. Both the breathing and the beat frequencies are also calculated for other graded-index profiles, such as those with additional higher-power terms, and are found to be extremely sensitive to the index profile. In media with linear and nonlinear absorption, we demonstrate the difference between the breathing behavior in graded-index and homogeneous waveguides.  相似文献   

7.
Respiratory function during speaking and singing was investigated in six male professional country singers. Function was studied using magnetometers to transduce anteroposterior diameter changes of the rib cage and abdomen while subjects performed various respiratory maneuvers, speaking activities, and singing activities. Results indicated that respiratory behavior during speaking was generally the same as that of other normal subjects. Respiratory behavior during singing resembled that of speaking. Discussion includes comparison of respiratory performance of present singers with untrained singers and classically trained singers. Implications are offered regarding how the results might be applied to the prevention of voice disorders by education and training of country singers.  相似文献   

8.
Although the songs of humpback whales have been extensively studied, other vocalizations and percussive sounds, referred to as "social sounds," have received little attention. This study presents the social vocalization repertoire of migrating east Australian humpback whales from a sample of 660 sounds recorded from 61 groups of varying composition, over three years. The social vocalization repertoire of humpback whales was much larger than previously described with a total of 34 separate call types classified aurally and by spectrographic analysis as well as statistically. Of these, 21 call types were the same as units of the song current at the time of recording but used individually instead of as part of the song sequence, while the other 13 calls were stable over the three years of the study and were not part of the song. This study provides a catalog of sounds that can be used as a basis for future studies. It is an essential first step in determining the function, contextual use and cultural transmission of humpback social vocalizations.  相似文献   

9.
Mobile telephones, company ID badges, and similar common devices form a sensor network which can be used to map human activity, and especially human interactions. The most informative sensor data seem to be measurements of person-to-person proximity, and statistics of vocalization and body movement measurements. Using this data to model individual behavior as a stochastic process allows prediction of future activity, with the greatest predictive power obtained by modeling the interactions between individual processes. Experiments show that between 40% and 95% of the variance in human behavior may be explained by such models.  相似文献   

10.
The vocalization behavior of Mongolian gerbils, a model animal of auditory physiology, was examined. A pair of gerbils was placed in a chamber, and their species-specific vocalizations and locomotive behaviors were recorded and analyzed. Two types of calls were predominantly produced: high-frequency upward frequency-modulated (HU-FM) calls and low-frequency multi-harmonic frequency-modulated (LM-FM) calls. Emission rates of HU-FM calls significantly decreased as the distance between the two gerbils increased, and playback of simulated HU-FM calls increased the emission rates. Acoustic analysis of HU-FM calls showed that the calls exhibited a stereotypic spectro-temporal structure including a fixed inter-onset interval (100-175 ms) and that individual differences in the frequency could convey the body size of the callers. The timing of HU-FM calls was highly synchronized with jump movements when an animal vocalized while jumping, suggesting the existence of tight locomotor-vocal coupling. Conversely, LM-FM calls were observed only when the gerbils tactilely contacted with each other while fighting over a food. These results suggest that Mongolian gerbils change the rates of call emissions and call types (e.g., LM-FM or HU-FM calls) in response to changes in visual and possibly tactile and auditory information. The functions of both calls are discussed in terms of their acoustic structures.  相似文献   

11.
A new experiment for selective determination of the relaxation rates of fast relaxing NMR signals is presented. The experiment is derived from the conventional inversion recovery experiment by substituting the 180 degrees inversion pulse of this experiment with a signal eliminating relaxation filter (SERF) consisting of three 180 degrees pulses separated by two variable delays, Delta1 and Delta2. The SERF experiment allows a selective suppression of signals with relaxation rates below a given limit while monitoring the relaxation of faster relaxing signals. The experiment was tested on a sample of 20% oxidized plastocyanin from Anabaena variabilis, where the fast exchange of an electron between the reduced (diamagnetic) and the oxidized (paramagnetic) form results in a series of average signals with widely different relaxation rates. To ensure an optimum extraction of information from the experimental data, the relaxation rates were obtained from the SERF experiment by a simultaneous analysis of all the FIDs of the experiment using a fast linear prediction model method developed previously. The reliability of the relaxation rates obtained from the SERF experiment was confirmed by a comparison of the rates with the corresponding rates obtained from a conventional inversion recovery experiment.  相似文献   

12.
A new numerical algorithm is developed for the solution of time-dependent differential equations of diffusion type. It allows for an accurate and efficient treatment of multidimensional problems with variable coefficients, nonlinearities, and general boundary conditions. For space discretization we use the multiwavelet bases introduced by Alpert (1993,SIAM J. Math. Anal.24, 246–262), and then applied to the representation of differential operators and functions of operators presented by Alpert, Beylkin, and Vozovoi (Representation of operators in the multiwavelet basis, in preparation). An important advantage of multiwavelet basis functions is the fact that they are supported only on non-overlapping subdomains. Thus multiwavelet bases are attractive for solving problems in finite (non periodic) domains. Boundary conditions are imposed with a penalty technique of Hesthaven and Gottlieb (1996,SIAM J. Sci. Comput., 579–612) which can be used to impose rather general boundary conditions. The penalty approach was extended to a procedure for ensuring the continuity of the solution and its first derivative across interior boundaries between neighboring subdomains while time stepping the solution of a time dependent problem. This penalty procedure on the interfaces allows for a simplification and sparsification of the representation of differential operators by discarding the elements responsible for interactions between neighboring subdomains. Consequently the matrices representing the differential operators (on the finest scale) have block-diagonal structure. For a fixed order of multiwavelets (i.e., a fixed number of vanishing moments) the computational complexity of the present algorithm is proportional to the number of subdomains. The time discretization method of Beylkin, Keiser, and Vozovoi (1998, PAM Report 347) is used in view of its favorable stability properties. Numerical results are presented for evolution equations with variable coefficients in one and two dimensions.  相似文献   

13.
This study was primarily motivated by the need to establish the correspondence between auditory abilities and laryngeal function. Just noticeable differences (JNDs) were obtained for the open quotient and speed quotient of the glottal flow waveform. The quotients were synthesized for both the glottal flow alone, and for the output pressure signal after the glottal flow signal was applied to the synthesis vocal tract for the vowel /a/. Six adult men and five adult women, all teachers of singing, participated as listeners. An adaptive auditory listening procedure was used to estimate JNDs for the four types of stimuli. The group average JND values were as follows. For the standard open quotient value of .6000, JND = 0.0264 (SD = .010) for the glottal flow and JND = 0.0344 (SD = .020) for the output pressure. For the open quotient, there was no statistically significant difference between genders or between the types of signals. For the standard speed quotient value of 2.000, JND = 0.154 (SD = .043) for the glottal flow and JND = 0.319 (SD = .167) for the output pressure. For the speed quotient, there was no statistically significant difference between genders, but the difference between types of stimulus (glottal flow versus output pressure) was significant (p <.006). The variance among the JND values was significantly larger for the output pressure stimuli compared to the glottal flow stimuli for both the open quotient and the speed quotient.  相似文献   

14.
Respiratory behavior is generally considered important to voice function, the assumption being that it affects the voice source. Accurate and consistent control of the voice source is particularly important in professional operatic singing. An erratic behavior of a factor influencing voice production is incompatible with a well-controlled vocal behavior. We analyzed the consistency of inhalatory breathing patterns during singing in five professional operatic singers, using the same material as in a previous investigation of phonatory breathing patterns. Rib cage (RC) and abdominal wall (AW) movements were recorded by respiratory inductive plethysmography. Consistency was analyzed in terms of the mean correlation between three takes of ten musical phrases. Results revealed a high consistency in lung volume (LV) change and RC movements in all singers and in AW movements in three singers. Consistency across different phrases was slightly lower. The results are compatible with the idea that inhalatory behavior is important to voice source in singing. A high correlation between LV change and RC movement was found in all singers and between LV change and AW movement in three. The contribution to LV change from RC was greater than that from AW in all singers.  相似文献   

15.
In this paper we introduce a high-order discontinuous Galerkin method for two-dimensional incompressible flow in the vorticity stream-function formulation. The momentum equation is treated explicitly, utilizing the efficiency of the discontinuous Galerkin method. The stream function is obtained by a standard Poisson solver using continuous finite elements. There is a natural matching between these two finite element spaces, since the normal component of the velocity field is continuous across element boundaries. This allows for a correct upwinding gluing in the discontinuous Galerkin framework, while still maintaining total energy conservation with no numerical dissipation and total enstrophy stability. The method is efficient for inviscid or high Reynolds number flows. Optimal error estimates are proved and verified by numerical experiments.  相似文献   

16.
We propose a new model and a solution method for two-phase compressible flows. The model involves six equations obtained from conservation principles applied to each phase, completed by a seventh equation for the evolution of the volume fraction. This equation is necessary to close the overall system. The model is valid for fluid mixtures, as well as for pure fluids. The system of partial differential equations is hyperbolic. Hyperbolicity is obtained because each phase is considered to be compressible. Two difficulties arise for the solution: one of the equations is written in non-conservative form; non-conservative terms exist in the momentum and energy equations. We propose robust and accurate discretisation of these terms. The method solves the same system at each mesh point with the same algorithm. It allows the simulation of interface problems between pure fluids as well as multiphase mixtures. Several test cases where fluids have compressible behavior are shown as well as some other test problems where one of the phases is incompressible. The method provides reliable results, is able to compute strong shock waves, and deals with complex equations of state.  相似文献   

17.
This article is a review of MPDATA, a class of methods for the numerical simulation of fluid flows based on the sign-preserving properties of upstream differencing. MPDATA was designed originally as an inexpensive alternative to flux-limited schemes for evaluating the advection of nonnegative thermodynamic variables (such as liquid water or water vapour) in atmospheric models. During the last decade, MPDATA has evolved from a simple advection scheme to a general approach for integrating the conservation laws of geophysical fluids on micro-to-planetary scales. The purpose of this paper is to summarize the basic concepts leading to a family of MPDATA schemes, to review existing MPDATA options, and to demonstrate the use of MPDATA to effectively construct two distinct types of models (elastic and anelastic) for complex geophysical flows.  相似文献   

18.
In an earlier study of inexact Newton methods, we pointed out that certain counterintuitive behavior may occur when applying residual backtracking to the Navier–Stokes equations with heat and mass transport. Specifically, it was observed that a Newton–GMRES method globalized by backtracking (linesearch, damping) may be less robust when high accuracy is required of each linear solve in the Newton sequence than when less accuracy is required. In this brief discussion, we offer a possible explanation for this phenomenon, together with an illustrative numerical experiment involving the Navier–Stokes equations.  相似文献   

19.
A recently described population of minke whales (Balaenoptera acutorostrata) offered a unique opportunity to study its acoustic behavior. The often-inquisitive dwarf minke whale is seen on the Great Barrier Reef nearly coincident with its suspected calving and breeding seasons. During drifting encounters with whales, a towed hydrophone array was used to record sounds for subsequent localization of sound sources. Shipboard and in-water observers linked these sounds to the closely circling minke whale. A complex and stereotyped sound sequence, the "star-wars" (SW) vocalization, was recorded during a series of visual and acoustic observations. The SW vocalization spanned a wide frequency range (50 Hz-9.4 kHz) and was composed of distinct and stereotypically repeated units with both amplitude and frequency-modulated components. Broadband source levels between 150 and 165 dB re 1 microPa at 1 m were calculated. Passive acoustic studies can utilize this distinct vocalization to help determine the behavior, distribution, and movements of this animal. While the SW vocalization's function remains unknown, the regularly repeated and complex sound sequence was common in low latitude, winter month aggregations of minke whales. At this early stage, the SW vocalization appears similar to the songs of other whale species and has characteristics consistent with those of reproductive advertisement displays.  相似文献   

20.
This paper examines how breathing differs in the upright and supine body positions. Passive and active forces and associated chest wall motions are described for resting tidal breathing and speech breathing performed in the two positions. Clinical implications are offered regarding evaluation and treatment of breathing behavior in clients with speech and voice disorders.  相似文献   

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