Storgaardfraser1164

The results revealed a synergistic interaction of cues wherein the PFs for cues presented in combination exceeded the simple vector sum of the PFs for the cues presented individually. The results are discussed in terms of their implications for possible emergent properties of cues affecting performance in simulated cocktail-party listening.Contemporary high-resolution sonar systems use broadband pulses and long arrays to achieve high resolution. It is important to understand effects that high-resolution sonar systems might have on quantitative measures of the scattered field due to the seafloor. A quantity called the broadband scattering cross section is defined, appropriate for high-resolution measurements. The dependence of the broadband scattering cross section, σbb, and the scintillation index, SI, on resolution was investigated for one-dimensional rough surfaces with power-law spectra and backscattering geometries. Using integral equations and Fourier synthesis, no resolution dependence of σbb was found. The incoherently averaged frequency-domain scattering cross section has negligible bandwidth dependence. SI increases as resolution increases, grazing angle decreases, and spectral strength increases. PF04418948 This trend is confirmed for center frequencies of 100 and 10 kHz, as well as for power-law spectral exponents of 1.5, 2, and 2.5. The hypothesis that local tilting at the scale of the acoustic resolution is responsible for intensity fluctuations was examined using a representative model for the effect of slopes (inspired by the composite roughness approximation). It was found that slopes are responsible in part for the fluctuations, but other effects, such as multiple scattering and shadowing may also play a role.The extended Biot model for sands and silts is repurposed to include mud, but modifications are needed. The boundary between pore water and skeletal frame needs to be redefined because a significant fraction of the pore fluid is adsorbed onto the solid frame by electrostatic forces, and a proportion of the solid particles may be suspended in the pore fluid. Revil's relationships are used to simplify the input parameters. The frame elasticity equations are corrected to accommodate the sparse skeletal frame, which is supported by electrostatic forces, and behaves differently to a mechanical packing of grains. The corrected, Revil, extended Biot model has just four fitting parameters and is compared with published measurements of wave speeds and attenuations in the literature of clay, silty clay, and clayey silt sediments including recently published measurements from the Seabed Characterization Experiment. The results indicate that the skeletal frame in clay has a high water-content and the pore water contains suspended particles. To fit all the currently available data, it was necessary to modify corrected, Revil, extended Biot by flattening the creep related relaxation loss spectrum. There is a similarity with the Viscous Grain Shearing models in the use of a fractional exponent.İstanbul's Hagia Sophia is a monumental structure with multiple sub-spaces coupled to one another through arches. Its architectural elements have undergone alterations as its function has changed from that of a church to a mosque, a mosque to a museum, and back to a mosque. This study makes use of Hagia Sophia's rich formal and material characteristics to conduct a comprehensive investigation of room acoustics coupling. The methodology involves the application of the diffusion equation model (DEM) for sound energy flow analysis. Energy flow decays and energy flow dips are examined for almost 1000 receiver positions distributed throughout the various sub-spaces of the building. Ray-tracing (Ray-t) simulations are used to support the energy flow decay analysis conducted using DEM. The Ray-t data are subjected to Bayesian analysis to identify the decay parameters and the degree of acoustical coupling. Among the many variables, the source-receiver distance and positioning within different sub-spaces appear to be the underlying determinant of multi-slope sound decay pattern. On the other hand, the cases of multi-slope decays identified within the structure tend to weaken and single-slope cases increase when the overall absorption area increases in the mosque state due to the carpeted floor.No agreed-upon method currently exists for objective measurement of perceived voice quality. link2 This paper describes validation of a psychoacoustic model designed to fill this gap. This model includes parameters to characterize the harmonic and inharmonic voice sources, vocal tract transfer function, fundamental frequency, and amplitude of the voice, which together serve to completely quantify the integral sound of a target voice sample. In experiment 1, 200 voices with and without diagnosed vocal pathology were fit with the model using analysis-by-synthesis. The resulting synthetic voice samples were not distinguishable from the original voice tokens, suggesting that the model has all the parameters it needs to fully quantify voice quality. In experiment 2 parameters that model the harmonic voice source were removed one by one, and the voice tokens were re-synthesized with the reduced model. In every case the lower-dimensional models provided worse perceptual matches to the quality of the natural tokens than did the original set, indicating that the psychoacoustic model cannot be reduced in dimensionality without loss of fit to the data. Results confirm that this model can be validly applied to quantify voice quality in clinical and research applications.This paper is part of a special issue on Modelling of Musical Instruments. The Sarasvati veena is a South Indian plucked string wooden lute, whose unique timbre is characterized by the presence of nearly all harmonics, in the range from 0 to 2800 Hz, the augmentation of the second and third harmonic and the revival of higher harmonics with time. This can be attributed to the shape of its extended bridge and its wooden resonator. In this work, the vibrational modes of the resonator are studied and the corresponding frequencies related to the musical tones generated while playing the veena. Numerical modal analysis is performed by the finite element method on a computer-aided design model of the resonator top plate as well as the air cavity within the dome-shaped structure. The results are compared to the experiment for validation. The resonator modes provide support to the harmonics of the string vibrations and give rise to the typical timbre of the instrument. We also find that other mode frequencies of the resonator support microtones that are used in Indian raga music. This gives scientific basis to the role of the timbre of the veena in supporting the development and sustenance of South Indian classical music.Unstressed syllables in English most commonly contain the vowel quality [ə] (schwa), which is cross-linguistically described as having a variable target. The present study examines whether speakers are sensitive to whether their auditory feedback matches their target when producing unstressed syllables. When speakers hear themselves producing formant-altered speech, they will change their motor plans so that their altered feedback is a better match to the target. If schwa has no target, then feedback mismatches in unstressed syllables may not drive a change in production. In this experiment, participants spoke disyllabic words with initial or final stress where the auditory feedback of F1 was raised (Experiment 1) or lowered (Experiment 2) by 100 mels. Both stressed and unstressed syllables showed adaptive changes in F1. In Experiment 1, initial-stress words showed larger adaptive decreases in F1 than final-stress words, but in Experiment 2, stressed syllables overall showed greater adaptive increases in F1 than unstressed syllables in all words, regardless of which syllable contained the primary stress. These results suggest that speakers are sensitive to feedback mismatches in both stressed and unstressed syllables, but that stress and metrical foot type may mediate the corrective response.We investigate the feasibility of imaging localized velocity contrasts within a nonattenuating acoustic medium using volume-distributed random point sources. We propose a simple, two-step processing flow that utilizes the linear sampling method to invert for the target locations directly from the recorded waveforms. We present several proof-of-concept experiments using Monte Carlo simulations to generate independent realizations of band limited "white noise" sources, which are randomly distributed in both time and space. Despite the unknown and random character of the illumination on the imaging targets, we show that it is possible to image strong velocity contrasts directly from multiply scattered coda waves in the recorded data. link3 We benchmark the images obtained from the random-source experiments with those obtained by a standard application of the linear sampling method to analogous controlled-source experiments.Acoustic metamaterials are a class of artificially periodic structures with extraordinary elastic properties that cannot be easily found in naturally occurring materials and can be applied to regulate the sound propagation behavior. The fractal configuration can be widely found in the acoustic system, like characterizing the broadband or multi-band sound propagation. This work will engineer three-dimensional (3D) labyrinthine fractal acoustic metamaterials (LFAMs) to regulate the sound propagation on subwavelength scales. The dispersion relations of LFAMs are systematically analyzed by the Bloch theory and the finite element method (FEM). The multi-bands, acoustic modes, and isotropic properties characterize their acoustic wave properties in the low-frequency regime. The effective bulk modulus and mass density of the LFAMs are numerically calculated to explain the low-frequency bandgap behaviors in specific frequencies. The transmissions and pressure field distributions of 3D LFAMs have been used to measure the ability for sound suppression. Furthermore, when considering the thermo-viscous loss on the transmission properties, the high absorptions occur within the multi-band range for low-frequency sound. Hence, this research contributes to potential applications on 3D LFAMs for multi-bands blocking and/or absorption on deep-subwavelength scales.Confinement due to the COVID-19 pandemic drastically reduced human activities. Underwater soundscape variations are discussed in this study, comparing a typical and confinement day in a coastal lagoon near a popular tourist city in Mexico. Recording devices were located at 2 m in depth and 430 m away from the main promenade-a two-way avenue for light vehicle traffic-where main tourist infrastructure is located. The nearby marine environment is habitat to birds and dolphins as well as fish and invertebrates of commercial importance. Medium and small boats usually transit the area. The main underwater sound level reduction was measured at low frequencies (10-2000 Hz) because of the decrease in roadway noise. Vessel traffic also decreased by almost three quarters, although the level reduction due to this source was less noticeable. As typical day levels in the roadway noise band can potentially mask fish sounds and affect other low frequency noise-sensitive marine taxa, this study suggests that comprehensive noise analysis in coastal marine environments should consider the contribution from nearby land sources.