Parametric modeling of vibroacoustic discrete-time random processes and application for the identification of oscillatory systems
Parametric modeling of vibroacoustic discrete-time random processes and application for the identification of oscillatory systems
I. A. Karpov
Autoregressive models of vibroacoustic signals are used to measure parameters of vibrational systems, in particular, to measure their losses.
Show AbstractAbsorption of noise on its active cancelation in air duct
Absorption of noise on its active cancelation in air duct
A. A. Pudovkin$^1$, D. I. Keshkov$^2$, M. Yu. Kitanov$^2$, G. N. Kuznetsov$^1$, S. I. Kutakov$^1$, A. B. Maizel$^2$, D. A. Smagin$^3$, A. A. Sukhartsov$^1$
Wideband noise and vibration cancellation is one of the actual acoustical task. Low-frequency excitation cancellation is an intricate problem especially in wide frequency band. Due to the insufficient efficiency of passive absorbers at low frequencies, active methods and technical means are recommended for attenuation of disturbances. The active cancellation problem decision is illustrated in presentation with regard to the air duct in which wide frequency band excitation is propagated. The noise disturbance power attenuation averaged in the operating frequency band was 11–12 dB. The maximum spectral densities are suppressed at 16–17 dB.
Show AbstractCorrelation of speech intelligibility and spectral resolutional in patients after cochlear implantation
Correlation of speech intelligibility and spectral resolutional in patients after cochlear implantation
M. V. Goykhburg$^1$, V. V. Bakhshinyan$^2$, A. -. Warzybok$^3$, B. -. Williges$^4$, T. -. Jürgens$^5$, G. A. Tavartkiladze$^6$
One of the most frequent complaints from patients with bilateral sensorineural deafness after cochlear implantation (CI) is the deterioration of speech intelligibility in a noisy environment. International researches have proven a correlation between speech intelligibility and spectral hearing resolution (HRS) in normal hearing subjects. The aim of the study was to determine the correlation of speech intelligibility in noise in CI users with HRS. Materials and methods of research: to estimate the speech intelligibility in noise the international Oldenburg test RUMatrix was used, to determine the HRS – SMRT test (spectrum-temporarily modulated riple test) was applied. The control group included 15 subjects without hearing impairment examined in the original version of the tests and using a vocoder. The study included 22 patients after CI implanted with «Cochlear» CI systems with experience of using CI system for more than 3 years. Results: The study performed in the control group revealed a high correlation of SMRT test and RUMatrix test results. The group of patients after CI consisted of pre- and postlingvally deafened patients. A correlation between speech intelligibility in noise and HRS (R2 = 0.55) was found in patients with postlingual deafness, and no correlation was found in the prelingual group (R2 = 0.03). Conclusions: The SMRT test correlates with speech audiometry data which allows to recommend its use to assess patients rehabilitation outcomes regardless of the level of speech development.
Show AbstractBiofabrication of a ring-shaped construct from tissue spheroids in a magnetoacoustic field
Biofabrication of a ring-shaped construct from tissue spheroids in a magnetoacoustic field
A. A. Krokhmal$^1$, O. A. Sapozhnikov$^1$, S. A. Tsysar$^1$, E. V. Koudan$^2$, E. K. Nezhurina$^2$, Yu. D. Khesuani$^2$, V. A. Parfenov$^2$
А new method for the biofabrication of tissue engineering constructs from tissue spheroids was proposed, based on the manipulation of spheroids using magnetic and acoustic radiation forces. Unlike most modern methods that use scaffolds to shape the structure, the proposed method fabricates levitating spheroids. The levitation effect is achieved due to the strong magnetic field gradient and the difference in the paramagnetic susceptibilities of the spheroids and the solution in which they are located. The structure was formed in an area where gravity was compensated by magnetic forces in the vertical direction, and due to the magnetic gradient in the horizontal plane, the tissue spheroids moved towards each other, rising above the bottom of the container. In turn, the acoustic field formed the structure of the assembled tissue-engineering structure. One of the most desirable forms is a ring or tube, since it is precisely this form that vessels in human tissues have. This shape was fabricated using a cylindrical piezoelectric transducer, which created a standing cylindrical ultrasonic field. The acoustic radiation force acted from the antinode to the node, forming a ring of tissue spheroids. Holding spheroids in such a trap for 18–20 hours led to their fusion into continuous living tissue in the form of a ring. Changing the frequency and amplitude of the ultrasonic wave made it possible to regulate the diameter and thickness of the conglomerate of spheroids.
Show AbstractInhomogeneous sound speed field in the seabed of the Kara Sea and its effect on acoustic wave propagation
Inhomogeneous sound speed field in the seabed of the Kara Sea and its effect on acoustic wave propagation
M. V. Volkov$^{1,3}$, V. A. Grigoriev$^2$, A. A. Lunkov$^{1,3}$, V. G. Petnikov$^1$
A statistical analysis of spatial variations in the sound speed in the upper sedimentary layer for one of the regions of the Kara Sea was carried out. For analysis, we used the distribution of sound speed obtained from 3D seismic data. A spatial anisotropy of this quasi-random physical quantity was found. Its spatial correlation radius can vary from hundreds of meters to a few kilometers, depending on the chosen direction in the horizontal plane. The problem of normal mode coupling in a shallow water area of a constant depth at a frequency of 250 Hz above the bottom with varying impedance is considered. It was assumed that the change in impedance is due to the variations in the sound velocity profile in the bottom sedimentary layer noted above. It is shown that for typical horizontal gradients of the sound speed in the bottom of the Kara Sea and when using a point sound source, the mode coupling is weak, therefore, the adiabatic approximation can be used to calculate the sound field. However, this coupling can be noticeable upon excitation of individual waveguide modes.
Show AbstractSeismoacoustic modes tomography of sediments, water column and ice of shallow sea
Seismoacoustic modes tomography of sediments, water column and ice of shallow sea
D. A. Presnov$^1$, A. L. Sobisevich$^1$, A. S. Shurup$^{1,2}$
Paper presents the results of full-scale tests in ice conditions of Ladoga Lake of marine seismic survey sources and the area measuring seismic-acoustic system based on autonomous buoys of frozen type. The possibility of normal modes separation in the received signal, spreading in the layered system "ice cover - water layer - sedimentary layer - elastic half-space" is demonstrated. Based on the analysis of the solution of the direct problem, effective numerical algorithms of tomographic evaluation of the characteristics of the bottom, water layer and ice cover are constructed.
Show Abstract≈700 Hz in Russian authentic singing phonation
≈700 Hz in Russian authentic singing phonation
S. Y. Gutova
This article presents data on the experimental measurement of the acoustic signal of the vocal speech of Russian ethnic singers, performed by the syllable articulation method. Three groups of performers took part in this study: traditional singers from various regions of Russia, professional singers and semi-professional art performers working in a folklorized manner, and the author’s students. The study found that in the authentic voice a stable presence of the oscillation frequency of ≈700 Hz is detected. There is reason to believe that this frequency, which is the first harmonic to the fundamental tone f0, in this case the first octave, and associated to low and medium singing formants, is important for the overtone-resonant coloring of the Russian traditional ethnic singing. This frequency is observed only in 40% of cases of a folklorized voice, while in an authentic voices – up to 90%. An experiment with a frequency gain of ≈700 Hz, conducted on students, showed the possibility of successful learning by the method of harmonic amplification to improve vocal sound. Based on the results of this experiment and the results of other researchers, the author came to the conclusion that frequencies of ≈700 Hz are associated with the biophysical properties of the human speech and respiratory system, which means that the given frequency is reasoned by a natural acoustic mechanism.
Show AbstractAcoustic emission from frozen soil foundations during their re-alternating thermome-chanical loading
Acoustic emission from frozen soil foundations during their re-alternating thermome-chanical loading
E. A. Novikov, M. G. Zaytsev, E. A. Kliment'ev
The regularities of acoustic emission in frozen soils of different material composition exposed to multiple cycles of thawing-freezing and being under the influence of quasi-static uniaxial mechanical load were experimentally established. The influence of the soil texture, the degree of its salinity, the variable intensity of the temperature effect and the heterogeneity of the dis-tribution of the thermal gradient on these regularities was studied. The characteristics and de-sign of the hardware system necessary to perform these studies were presented. This system also makes it possible to verify the results of acoustic measurements simultaneously by their comparison with the obtained data of ultrasonic sounding and the results of measurement of the resistance of the probe penetration into the soil. The technique of interpretation of the es-tablished acoustic-emission regularities was described and substantiated which allows to esti-mate the bearing capacity and the stage of the deformed state by the parameters and the na-ture of the acoustic emission of the soil material taking into account the action of the above factors.
Show AbstractAcoustic semantic content of speech communication in robotics
Acoustic semantic content of speech communication in robotics
R. K. Potapova$^1$, V. V. Potapov$^2$
The paper presents an original approach to the investigation of acoustic semantic content that ensures the effect of reciprocal human-machine and machine-human communication, which is one of the top priority tasks for fast stimulus-reaction ↔ reaction-stimulus model based interaction engineering in the modern research field that is now termed Interactive Communicative Robotics (see also: R. Potapova “Speech Dialogue as a Part of Human-Machine Interactive Systems” in: “Interactive Collaborative Robotics. 1st International Conference – ICR 2016”, LNAI 9812, Springer International Publishing, pp. 208–218). At the present stage various human-machine interface models making part of interactive robotic systems are being developed. Alongside visual image recognition (mimics, gestures etc), acoustic semantic content investigations, including the development of problem-oriented databases, knowledge bases, algorithms for controlling the communicative act, type and degree of interactiveness, is one of the essential areas forming the basis of the mentioned research field.
Show AbstractAcoustic imaging of objects in liquids using a matrix of rod waveguides
Acoustic imaging of objects in liquids using a matrix of rod waveguides
S. A. Petrosyan$^1$, S. A. Tsysar$^1$, V. D. Svet$^3$, O. A. Sapozhnikov$^2$
There are several acoustic imaging methods for studying opaque liquids with thermal inhomogeneities, for example, aggressive chemically active liquids and molten metals, where the use of electromagnetic waves is often difficult or simply impossible, and the use of acoustic transducers for receiving ultrasonic waves involves difficulties. The main problem in this case is the protection of the piezoelectric transducer from the influence of an aggressive environment and the relatively low sensitivity of high-temperature receiving piezoelectric sensors, which complicates the use of traditional ultrasound imaging systems. In this paper, we propose a method for detecting and visualizing objects using a scanning echo-pulse system, in which acoustic signals are received through waveguides in the form of steel rods. The echo pulse can be emitted into a liquid using a high-temperature piezoelectric transducer that can withstand such harsh conditions, or through a rod waveguide, the end of which is in an environment with safe working conditions. This end is the source of the ultrasonic signal. The other end is immersed in an aggressive liquid and brought to the investigated area to probe it. To register an ultrasonic echo signal reflected from the investigated object, a multichannel waveguide system is used in the form of a bundle of metal rods, one end of which is located near the visualization object, providing a wide viewing angle and high resolution. The rods are long enough, so that the second end of the specified bundle is located outside the aggressive fluid, where it is already possible to receive signals by traditional methods.
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