Articles de revues : « Acoustic regularities »

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Bondarenko, Veronika, et Alexander Chukarin. « GENERATION REGULARITIES OF VIBRATION AND NOISE SPECTRA OF THE GEARBOXES OF OVERHEAD TRAVELING CRANES ». Akustika 32 (1 mars 2019) : 120–22. http://dx.doi.org/10.36336/akustika201932120.

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The acoustic system of the overhead traveling cranes includes the following diverse sources of acoustical radiation: rails, wheel sets, a base frame, gears and motors of the lifting and moving mechanisms. The acoustic characteristics of the motors do not exceed the maximum permissible sound pressure levels. The gearboxes as the sources of noise and vibration are the most complicated units; moreover, they arrive at the manufacturing factories already being assembled. Therefore, when assessing the sound pressure levels of the cranes in whole, it is advisable to use the experimental data of the noise and gearbox vibration spectra.

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de Boer, Bart. « Evolution and self-organisation in vowel systems ». Phonetics of the Origins and Evolution of Speech 3, n^o 1 (31 décembre 1999) : 79–103. http://dx.doi.org/10.1075/eoc.3.1.06boe.

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This paper describes computer simulations that investigate the role of self-organisation in explaining the universals of human vowel systems. It has been observed that human vowel systems show remarkable regularities, and that these regularities optimise acoustic distinctiveness and are therefore adaptive for good communication. Traditionally, universals have been explained as the result of innate properties of the human language faculty, and therefore need an evolutionary explanation. In this paper it is argued that the regularities emerge as the result of self-organisation in a population and therefore need not be the result of biological evolution. The hypothesis is investigated with two different computer simulations that are based on a population of agents that try to imitate each other as well as possible. Each agent can produce and perceive vowels in a human-like way and stores vowels as articulatory and acoustic prototypes. The aim of the agents is to imitate each other as well as possible. It will be shown that successful repertoires of vowels emerge that show the same regularities as human vowel systems.

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Ryabov, V. A. « Hydroacoustical regularities of food behavior of dolphins ». Marine Biological Journal 3, n^o 2 (29 juin 2018) : 81–97. http://dx.doi.org/10.21072/mbj.2018.03.2.07.

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Hydroacoustic regularities of food behavior of dolphins are determined by characteristics and functionality of their acoustic signals. All the acoustic signals of dolphins are classified depending on their physical characteristics by the theory of signals and echolocation as follows: sequences of ultrashort ultrawideband coherent pulses – ‘clicks’, frequency-modulated (FM) simultones with uniformly distributed tones – ‘whistles’, packets of mutually coherent pulses (CI), packets of mutually noncoherent pulses (NI) and packets of versatile pulses (VI). They play the role of probing signals of six dolphin sonars optimized for solving various echolocation tasks. The possibilities of using the signals by dolphins in searching and classifying food objects by echolocation have been studied in this work on the basis of both experimental data obtained by the researcher and those available in literature. The dolphins can use sequences of ‘clicks’ to detect food objects (individual fish at the distance up to 70–110 m, a school of fish at the distance up to 450–600 m) and conspecifics (dolphins) (at the distance up to 450–600 m) and to classify food objects. The dolphins can use ‘whistles’ to detect food objects (individual fish at the distance up to 2 km, a school of fish at the distance up to 9–13 km) and conspecifics (dolphins) (at the distance up to 9–13 km) and to determine their range and relative radial velocity. ‘Whistles’ provide higher accuracy and the range of echolocation of food objects and conspecifics compared to ‘clicks’ (by more than an order of magnitude). Furthermore, the FM sonar provides the measure of the radial velocity of approaching or distance removing of underwater object to or from a dolphin. However, an acute analysis of the amplitude-time regularities of the fish echo for the purpose of their classification is the advantage of sonar using ‘clicks’. The dolphins can use the packs of CI at the distances shorter than 2.5 m for tracing the position dynamics of the prey aiming at accurate capture. The high hearing resolution of the dolphin in time is about 0.02 ms; it allows processing the subtle temporal dynamics of the echoes. Packs of NI (signals of spoken language) can be used by dolphins to organize various types of association and complex cooperation between themselves when hunting and catching fish. Packets of VI can be used by dolphins to expand the echolocation of the survey area around the dolphin in order to improve the quality of food objects monitoring, regardless of the position of the dolphin’s head, as well as to determine the range, relative radial velocity and class of food objects, at short distances. Evolution and perfection of various types of acoustic signals, sonars and various methods of processing echo signals in dolphins is caused, first of all, by optimization of hydroacoustic regularities of their food behavior, along with the need for orientation in three-dimensional space. One can assume the presence of similar hydroacoustic regularities of food behavior in Odontoceti based on the similarity of their acoustic signals and morphology. The acoustic regularities of food behavior of dolphins and bats are similar, despite the fact that they have different habitats (water and terrestrial-air), and these mammals belong to different orders of the animal kingdom (Сetacea and Chiroptera).

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Filonenko, Sergey, et Aleksandr Kosmach. « ACOUSTIC EMISSION IN THE FRICTION OF COMPOSITE MATERIALS ». Aviation 18, n^o 2 (2 juillet 2014) : 57–63. http://dx.doi.org/10.3846/16487788.2014.926640.

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The model of acoustic emission signal formation during friction and wearing of surfaces of composite materials was examined. The forms of acoustic emission resultant signals were shown. The regularities of parameter change in acoustic emission resultant signals with an increasing rotation speed were determined according to the results of modeling. It was found that theoretical and experimental results of acoustic emission signals registered during friction of composite material surface layers agree well.

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Besle, Julien, Zahra Hussain, Marie-Hélène Giard et Olivier Bertrand. « The Representation of Audiovisual Regularities in the Human Brain ». Journal of Cognitive Neuroscience 25, n^o 3 (mars 2013) : 365–73. http://dx.doi.org/10.1162/jocn_a_00334.

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Neural representation of auditory regularities can be probed using the MMN, a component of ERPs generated in the auditory cortex by any violation of that regularity. Although several studies have shown that visual information can influence or even trigger an MMN by altering an acoustic regularity, it is not known whether audiovisual regularities are encoded in the auditory representation supporting MMN generation. We compared the MMNs elicited by the auditory violation of (a) an auditory regularity (a succession of identical standard sounds), (b) an audiovisual regularity (a succession of identical audiovisual stimuli), and (c) an auditory regularity accompanied by variable visual stimuli. In all three conditions, the physical difference between the standard and the deviant sound was identical. We found that the MMN triggered by the same auditory deviance was larger for audiovisual regularities than for auditory-only regularities or for auditory regularities paired with variable visual stimuli, suggesting that the visual regularity influenced the representation of the auditory regularity. This result provides evidence for the encoding of audiovisual regularities in the human brain.

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Bekher, S. « Regularities of Acoustic Emission in the Freight Car Solebar Materials ». Journal of Physics : Conference Series 671 (18 janvier 2016) : 012005. http://dx.doi.org/10.1088/1742-6596/671/1/012005.

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Shkuratnik, V. L., Yu L. Filimonov et S. V. Kuchurin. « Regularities of Acoustic Emission in Coal Samples under Triaxial Compression ». Journal of Mining Science 41, n^o 1 (janvier 2005) : 44–52. http://dx.doi.org/10.1007/s10913-005-0062-8.

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Vil’yaminov, S. V., A. S. Voznesensky, V. V. Nabatov et V. L. Shkuratnik. « Regularities and mechanisms of thermal acoustic emission in gypseous rocks ». Journal of Mining Science 45, n^o 6 (novembre 2009) : 533–40. http://dx.doi.org/10.1007/s10913-009-0067-9.

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Winkler, István, et Nelson Cowan. « From Sensory to Long-Term Memory ». Experimental Psychology 52, n^o 1 (janvier 2005) : 3–20. http://dx.doi.org/10.1027/1618-3169.52.1.3.

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Abstract. Everyday experience tells us that some types of auditory sensory information are retained for long periods of time. For example, we are able to recognize friends by their voice alone or identify the source of familiar noises even years after we last heard the sounds. It is thus somewhat surprising that the results of most studies of auditory sensory memory show that acoustic details, such as the pitch of a tone, fade from memory in ca. 10-15 s. One should, therefore, ask (1) what types of acoustic information can be retained for a longer term, (2) what circumstances allow or help the formation of durable memory records for acoustic details, and (3) how such memory records can be accessed. The present review discusses the results of experiments that used a model of auditory recognition, the auditory memory reactivation paradigm. Results obtained with this paradigm suggest that the brain stores features of individual sounds embedded within representations of acoustic regularities that have been detected for the sound patterns and sequences in which the sounds appeared. Thus, sounds closely linked with their auditory context are more likely to be remembered. The representations of acoustic regularities are automatically activated by matching sounds, enabling object recognition.

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Morozov, S. A., et A. N. Chukarin. « PILOT STUDIES OF PROCESS OF VIBROACOUSTIC DYNAMICS AT LOCAL HARDENING OF DETAILS A SHARIKO-ROD UPROCHNITEL ». Herald of Dagestan State Technical University. Technical Sciences 45, n^o 4 (27 juin 2019) : 52–58. http://dx.doi.org/10.21822/2073-6185-2018-45-4-52-58.

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Objectives The most important problem of modern mechanical engineering is increase in durability of products, their efficiency and competitiveness in the world market. The equipment for machining creates the increased noise levels in a working zone of operators. Now regularities of formation of acoustic characteristics are studied generally for metal-cutting and woodworking machines of various types. Formation of the sound field at shariko-rod hardening is studied insufficiently. The purpose of researches which results are given in this article consisted in studying of regularities of spectral structure of noise and vibrations when processing ShSU of details with various ways of fixing. Method. In the course of pilot studies the known methods of measurement and processing of experimental data in relation to acoustic and vibration characteristics were used. Results. It is established that noise ranges at ShSU of details with various ways of fixing have identical regularities of a shumoobrazovaniye and are characterized by pronounced high-frequency character. It is proved that the dominating sources yaa-lyatsya the strengthened detail and an uprochnitel. Conclusion. Sizes of excesses of levels of sound pressure systems "up-rochnitel-detal2 in a high-frequency part of a range 500-8000gts are installed. The established regularities of formation of spectral structure are a basis for the choice of means of decrease in noise levels. Work is performed within initiative research work.

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Bespal’ko, Anatoly, Anatoly P. Surzhikov, Pavel Fedotov, Evgeniy Pomishin et Oldrich Stary. « Polarization and Electromagnetic Emissions of Natural Crystalline Structures upon Acoustic Excitation ». Materials Science Forum 970 (septembre 2019) : 153–66. http://dx.doi.org/10.4028/www.scientific.net/msf.970.153.

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A surface charge density distribution on natural crystal samples is investigated in the paper. Here are revealed regularities of electromagnetic signal amplitude changes upon acoustic excitation of electrified calcite samples depending on the size of the crystals.

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Balakshy, Vladimir, Maxim Kupreychik, Sergey Mantsevich et Vladimir Molchanov. « Acousto-Optic Cells with Phased-Array Transducers and Their Application in Systems of Optical Information Processing ». Materials 14, n^o 2 (18 janvier 2021) : 451. http://dx.doi.org/10.3390/ma14020451.

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This paper presents the results of theoretical and experimental studies of anisotropic acousto-optic interaction in a spatially periodical acoustic field created by a phased-array transducer with antiphase excitation of adjacent sections. In this case, contrary to the nonsectioned transducer, light diffraction is absent when the optical beam falls on the phased-array cell at the Bragg angle. However, the diffraction takes place at some other angles (called “optimal” here), which are situated on the opposite sides to the Bragg angle. Our calculations show that the diffraction efficiency can reach 100% at these optimal angles in spite of a noticeable acousto-optic phase mismatch. This kind of acousto-optic interaction possesses a number of interesting regularities which can be useful for designing acousto-optic devices of a new type. Our experiments were performed with a paratellurite (TeO2) cell in which a shear acoustic mode was excited at a 9∘ angle to the crystal plane (001). The piezoelectric transducer had to nine antiphase sections. The efficiency of electric to acoustic power conversion was 99% at the maximum frequency response, and the ultrasound excitation band extended from 70 to 160 MHz. The experiments have confirmed basic results of the theoretical analysis.

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Filonenko, Sergii, et Anzhelika Stakhova. « Acoustic Emission at Properties Change of Composite Destructed by von Mises Criterion ». Electronics and Control Systems 1, n^o 67 (12 mai 2021) : 54–60. http://dx.doi.org/10.18372/1990-5548.67.15602.

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The results of theoretical studies influence the parameter characterizing the composite properties on acoustic emission signals parameters during composite material fracture by a shear force using von Mises criterion are considered. It has been determined that with increase of influencing parameter, there is decrease the maximum amplitude and duration of generated acoustic emission signals. In this case, a decrease the maximum amplitude of acoustic emission signals is ahead of decrease in their duration. It has been determined that the regularities of acoustic emission signals maximum amplitude and duration decrease with an increase the parameter characterizing the composite material properties are well described by power functions.

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Fesina, Mikhail, Igor Deryabin et Gorina Larisa. « ON THE RESULTS OF EXPERIMENTAL STUDIES OF THE PHYSICAL PROCESS OF GENERATING SOUND VIBRATIONS BEATS IN CLOSED AIR CAVITIES OF TECHNICAL ROOMS ». Akustika 32 (1 mars 2019) : 17–23. http://dx.doi.org/10.36336/akustika20193217.

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This paper gives the results of experimental researches for producing physical processes of acoustic vibration beats, which are spread in a free and in a diffused field of enclosed air volumes in technical rooms of different types. There are defined general regularities and distinct features of forming the physical processes of acoustic vibration beats. A limited frequency range of beats production which includes two different frequency ranges of dynamic frequency interactions with close values of sound frequencies are found out. Sufficiency of frequency detuning of two independent sources of acoustic radiation which exclude physical process creation of sound frequency beats is defined.

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Chukarin, Alexander, Besarion Meskhi et David Shoniya. « THEORETICAL ANALYSIS ON REGULARITIES OF THE PROCESS OF NOISE GENERATION OF PLANING, SLOTTING AND PLANING-MILLING MACHINES ». Akustika, VOLUME 41 (2021) : 173–77. http://dx.doi.org/10.36336/akustika202141173.

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The acoustic characteristics of the planing machines, which are the most widespread and the most noisy metalworking equipment, are considered. The article presents the theoretical models of the process of noise generation of planing, slotting and planing-milling machines. Regularities of sound pressure levels and sound power are obtained for brittle materials (cast iron blanks) mounted on the machine table. The regularities of the vibration velocities of the cutting tool and the workpiece are derived. The system of second-order differential equations is obtained for the version of the cantilever fixing of the planing cutter, using the developed approaches to the calculating vibrations and noise of machine equipment.

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Evano, Benjamin, François Lignières et Bertrand Georgeot. « Regularities in the spectrum of chaotic p-modes in rapidly rotating stars ». Astronomy & ; Astrophysics 631 (novembre 2019) : A140. http://dx.doi.org/10.1051/0004-6361/201936459.

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Context. Interpreting the oscillations of massive and intermediate mass stars remains a challenging task. In fast rotators, the oscillation spectrum of p-modes is a superposition of sub-spectra which corresponds to different types of modes, among which island modes and chaotic modes are expected to be the most visible. This paper is focused on chaotic modes, which have not been thoroughly studied before. Aims. We study the properties of high frequency chaotic p-modes in a polytropic model. Unexpected peaks appear in the frequency autocorrelations of the spectra. Our goal is to find a physical interpretation for these peaks and also to provide an overview of the mode properties. Methods. We used the 2D oscillation code “TOP” to produce the modes and acoustic ray simulations to explore the wave properties in the asymptotic regime. Using the tools developed in the field of quantum chaos (or wave chaos), we derived an expression for the frequency autocorrelation involving the travel time of acoustic rays. Results. Chaotic mode spectra were previously thought to be irregular, that is, described only through their statistical properties. Our analysis shows the existence, in chaotic mode spectra, of a pseudo large separation. This means that chaotic modes are organized in series, such that the modes in each series follow a nearly regular frequency spacing. The pseudo large separation of chaotic modes is very close to the large separation of island modes. Its value is related to the sound speed averaged over the meridional plane of the star. In addition to the pseudo large separation, other correlations appear in the numerically calculated spectra. We explain their origin by the trapping of acoustic rays near the stable islands.

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Shanyavskiy, Andrey, et Mukharbiy Banov. « Fatigue Cracking and Acoustic Emission Regularities in Metals : Crack Origination and Growth ». Key Engineering Materials 592-593 (novembre 2013) : 735–40. http://dx.doi.org/10.4028/www.scientific.net/kem.592-593.735.

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Specimens of Al-and Ti-alloys and turbine blades of Ni-based alloy were considered in the case of crack origination at the surface, subsurface, and at the inner surface of turbine blades. Aircraft structures such as hydrocylinders of Al-based alloy and landing gear of high-strength-steel were also considered. There was used acoustic emission (AE) monitoring to fix moment of crack occurring and, then, analyzing its growth. Fracture surface features appearance was compared with AE-signals regularities based on fractographic analyses. To indicate the crack origination moment it was introduced α-criterion. This criterion characterized drastically increase in summarized AE-signals appearing in dependence on cyclic loads number. During crack propagation, there was used Elber-portion of opened crack to register AE-signals in cyclic loads. It was demonstrated crack increment in unloading portion of cyclic loads with fatigue striations formation. Two aircraft structures of hydrocylinders and shock strut of landing gear were tested on the special test facilities and AE-monitoring was conducted. Effectiveness of α-criterion using for crack registration in the high-cycle fatigue regime was demonstrated applicably to crack appearance on the internal surface and subsurface. The discovered dependences of summarized AE-signals on number of cycles were compared with fracture surface patterns and briefly discussed.

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Gumenyuk, Valentina, Oleg Korzyukov, Kimmo Alho, István Winkler, Petri Paavilainen et Risto Näätänen. « Electric brain responses indicate preattentive processing of abstract acoustic regularities in children ». NeuroReport 14, n^o 11 (août 2003) : 1411–15. http://dx.doi.org/10.1097/00001756-200308060-00001.

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Banov,, Muharby D., Igor V. Pavelko, et Vitaly P. Pavelko,. « The Regularities of Acoustic Emission on Fatigue Destruction of an Aluminum Alloy ». Journal of the Mechanical Behavior of Materials 14, n^o 1 (février 2003) : 23–40. http://dx.doi.org/10.1515/jmbm.2003.14.1.23.

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Dudnik, A. A., A. S. Skripnik, A. D. Bezhan et V. B. Kolycheva. « Ultrasonic influence on the low-temperature conversion of petroleum products ». ТЕНДЕНЦИИ РАЗВИТИЯ НАУКИ И ОБРАЗОВАНИЯ 84, n^o 2 (2022) : 93–94. http://dx.doi.org/10.18411/trnio-04-2022-70.

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The article presents the results of a study of ultrasonic treatment influence on the lowtemperature conversion of petroleum products. The regularities of the behavior of the freezing temperature and density of samples depending on the frequency of acoustic vibrations are established. It is revealed how the component composition and physicochemical characteristics of the samples change.

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Filonenko, Sergay, Viacheslav Stadnychenko et Anzhelika Stakhova. « MODELLING OF ACOUSTIC EMISSION SIGNALS AT FRICTION OF MATERIALS’ SURFACE LAYERS/MEDŽIAGŲ PAVIRŠIAUS TRINTIES AKUSTINĖS EMISIJOS SIGNALŲ MODELIAVIMAS ». Aviation 12, n^o 3 (30 septembre 2008) : 87–94. http://dx.doi.org/10.3846/1648-7788.2008.12.87-94.

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A model of the signal of acoustic emission resulting from the normal wear of friction pairs is considered. Its mathematical description is obtained. Modelling of acoustic emission signals at varying strained/deformed state and rotation speed of initial friction pairs is done. The basic regularities of the transformation of acoustic emission form and those of its (emission) parameters of resulting signals are determined. Experimental research of acoustic emission signals is performed and proved to be good when compared to the results of theoretical research. Santrauka Išnagrinėtas akustinės emisijos signalų, kurie susidaro normaliame besitrinančių porų dilime, modelis ir jis matematiškai aprašytas. Atliktas akustinės emisijos signalų modeliavimas esant įvairiam pradinių trinties porų sukimosi greičiui ir įtempimų/deformacijų būsenai. Nustatyti pagrindiniai akustinės emisijos signalų formos ir parametrų transformacijos dėsningumai. Atliktas eksperimentinis akustinės emisijos signalų tyrimas, kurio rezultatai gerai sutapo su teoriniais.

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Gadalov, V. N., S. V. Safonov, E. A. Filatov, O. N. Boldyreva et I. A. Makarova. « The study of regularities of changes in acoustic characteristics depending on microstructure parameters and development of acoustic limit state criterion ». Glavnyj mekhanik (Chief Mechanic), n^o 10 (1 octobre 2020) : 32–42. http://dx.doi.org/10.33920/pro-2-2010-03.

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The studies of the dependence of acoustic characteristics on the microstructure of chromium-molybdenum-vanadium steels in various structural states after long term operation are presented. The meaning of the acoustic limit state criterion, which represents a relative assessment of accumulated structural damage of the long run metal for the time delay of ultrasonic Rayleigh waves and determination of the limit state of the material, is revealed. It is established that at the acoustic criterion of the limit state of ≥0.7, the metal is in the state of avalanche creep and reaches the limit state. Measurements of acoustic characteristics gave a good agreement with the results of metallographic studies conducted on sections of metal cuttings. In addition, the criterion was tested when diagnosing technical devices made of steel 15X1M1F, 12X2MFSR, 17GS, 09G2S.

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Vanyan, Lusine. « Rhythmic Arrangement of English Academic Discourse ». Armenian Folia Anglistika 11, n^o 2 (14) (15 octobre 2015) : 84–104. http://dx.doi.org/10.46991/afa/2015.11.2.084.

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The article addresses the problem of the rhythmic arrangement of academic discourse and its main units. It is the result of computer-based acoustic investigation of English rhythm (in comparison with Armenian). The contrastive analysis of the rhythmic units helps to reveal the regularities that pass unnoticed in monolingual studies. Basing on the scalar approach to the rhythm, the study defines rhythm as an output of all the gradients participating in its formation with the special accent on grouping and prominence. It is an attempt in modelling the rhythmic organisation of academic prose in English (Armenian) by giving its acoustic profile.

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Smirnov, Aleksandr, Nikolai Ababkov et Aleksandra Glinka. « Gradient Structures and Internal Stress Fields in Surface Layers of Products Made of Steel 0.35C-1Cr-1Mn-1Si after Turning ». Advanced Materials Research 1013 (octobre 2014) : 170–75. http://dx.doi.org/10.4028/www.scientific.net/amr.1013.170.

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The effect of different cutting (mechanical heat treatment) on the structural-phase condition and the internal stress field in the surface layers of the product is considered in the article. The regularities of acoustic characteristics depending on the parameters of the structure and stress for the development of nondestructive method for assessing the quality of the surface layer are identified

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Filonenko, Sergii, et Anzhelika Stakhova. « Acoustic Emission During Composites Fracture According von Mises Criterion and Changing of its Properties Disperstion ». Electronics and Control Systems 1, n^o 71 (27 juin 2022) : 28–35. http://dx.doi.org/10.18372/1990-5548.71.16819.

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The results of modeling composite elements process destruction by shear force according to von Mises criterion and acoustic emission signals generated with decrease of composite properties dispersion are considered. It has been determined that decrease of composite properties dispersion leads to increase the rate of fall the curves change in the remaining elements in time and decrease the time of fracture process. It was found that with decrease of composite properties dispersion there is increase of generated acoustic emission signal amplitude and decrease in its duration. It has been determined that the regularities of generated acoustic emission signals maximum amplitude increase and acoustic emission signals duration decrease are well described by power-law functions. Comparison of the obtained data with the data at composite destruction according to the OR criterion is carried out. It has been determined that the patterns of acoustic emission signals maximum amplitudes and durations change are similar. However, when using the OR criterion, the values of acoustic emission signals amplitudes and durations are higher than when using the Mises criterion.

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Козлова, V. Kozlova, Еськов, Valeriy Eskov, Хадарцев, Aleksandr Khadartsev, Филатова et O. Filatova. « Application of Statistical Methods and Multidimensional Phase Space Methods for Estimation of Chaotic Dynamics of Neuromuscular System Parameters under Acoustic Effects ». Journal of New Medical Technologies 21, n^o 2 (13 août 2014) : 6–10. http://dx.doi.org/10.12737/4987.

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A behavior of a human body state vector (for example, a reaction of tremorogramm parameters) in response to different acoustic effects (white noise, rhythmic music, classical music, hard rock) was studied using the statistical methods of the theory of chaos and self-organization. The authors showed the distinctions in estimation of behavioral dynamics of the neuromuscular system parameters, such as various motor reaction of the left and right hands to the acoustic effect. The common regularities in the dynamics of the neuromuscular system parameters behavioral parameters at various acoustic effects were revealed in Surgut students analyzing the differential responses of the left and right hands. Increased sizes of quasi-attractors of the right hand (under acoustic effects) and variations of quasi-attractors parameters of a left hand proved it. Simultaneously, tremor indicators for left and right hands differ (in 2-3 times). Asymmetry of motor responses from the standpoint of the theory of chaos and self-organization were more marked than according to the stochastic approach.

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Нехайчик, S. Nekhaychik, Козлова, V. Kozlova, Берестин, D. Berestin, Прасолова et A. Prasolova. « NEUROCOMPUTER use in an assessment of chaotic dynamics of parameters of neuromuscular system of the person at various acoustic influences ». Complexity. Mind. Postnonclassic 3, n^o 2 (21 mai 2014) : 13–28. http://dx.doi.org/10.12737/5515.

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The behavior of the human body state vector (for example, the reaction of tremoro-gram parameters) in response to different acoustic impacts (white noise, rhythmic music, classical music, hard rock) was studied by using the methods of neurocomputing. We showed the distinctions in the estimation of the behavioral dynamics of the parameters of the neuromuscular system, such as various motor reaction (tremor) of the left and right hands on the acoustic impact. The common regularities in the dynamics of behavior parameters of tremor at various acoustic impact on Surgut students hands were revealed. The analysis of quasi-attractors of differentiated reactions of left and right hands using neural emulators showed significant distinction on different types of acoustic impacts. Asymmetry of motor responses from the standpoint of the theory of chaos and self-organization was more marked than according to the stochastic approach. Neural emulator demonstrated the significance of all impacts on tremor parameters (system synthesis problem is being solved).

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Luor, Austin, Sahil Luthra, Barbara Shinn-Cunningham, Adam Tierney, Frederic Dick et Lori Holt. « Statistical regularities of task-irrelevant dimensions impact auditory decisions ». Journal of the Acoustical Society of America 152, n^o 4 (octobre 2022) : A230. http://dx.doi.org/10.1121/10.0016105.

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Listeners build up statistically driven expectations of what they will hear; however, there is no consensus on how these statistics influence perception, attention, and behavior. Here, we manipulate two statistical properties: global probability (the likelihood of single ‘sound events’) and predictiveness (how often does one sound precede another). We ask how the probability and predictiveness of different acoustic frequencies affect performance on two paradigms where frequency is task-irrelevant: suprathreshold duration identification and near-threshold tone-detection-in-noise. We found that duration decisions are faster and detection decisions are more accurate for high-probability tone frequencies, compared to low-probability tone frequencies. Moreover, when a preceding “cue” tone’s frequency predicts that of a subsequent “target” tone, listeners are faster at judging the duration of the target tone. This latter effect is not solely a result of temporal cueing, as target responses are not facilitated if a cue does not predict the target tone’s frequency. Blending these paradigms to examine the same global and transitional probabilities across duration and detection decisions suggests that statistical learning shapes attention to perceptual dimensions, even when the dimensions are irrelevant to optimal task performance.

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Peng, Zilong, Linjiang Han, Xirui Peng, Yipeng Cheng et Dong Ding. « Research and modeling of the bistatic acoustic scattering characteristics of novel multi-faceted conning tower ». Noise Control Engineering Journal 70, n^o 6 (1 novembre 2022) : 507–18. http://dx.doi.org/10.3397/1/377044.

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The overall acoustic echo of a submarine is greatly dependent on the conning tower. For enhancing the acoustic stealth performance of a submarine, it is necessary to research an innovative design scheme of the conning tower to reduce its bistatic target strength (TS). The aim of this work is to reduce the bistatic TS of a conning tower by varying its geometry and streamlining. The accuracy in modeling the acoustic scattering of a conning tower using the Kirchhoff approximation (KA) was validated, compared with finite element analysis. Several angular conning tower geometries were designed to analyze the effect of streamlining and the number of lateral facets on TS using the KA method. In consideration of the actual situation, the acoustic effect of backing medium was analyzed by comparing water-filled elastic hulls with rigid hulls. From the observed TS calculation results, it is shown that the non-streamlined four lateral-facet conning tower geometries are optimal for acoustic stealth performance during the range of receiving angles from -30 degrees to 30 degrees. Furthermore, elastic hulls and rigid hulls provide similar spatial distribution regularities in bistatic configuration with the rigidity affecting the magnitude of the TS.

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Reese, D. R., F. Lignières, J. Ballot, M. A. Dupret, C. Barban, C. van ’t Veer-Menneret et K. B. MacGregor. « Frequency regularities of acoustic modes and multi-colour mode identification in rapidly rotating stars ». Astronomy & ; Astrophysics 601 (mai 2017) : A130. http://dx.doi.org/10.1051/0004-6361/201321264.

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Althen, Heike, Sabine Grimm et Carles Escera. « Simple and complex acoustic regularities are encoded at different levels of the auditory hierarchy ». European Journal of Neuroscience 38, n^o 10 (1 septembre 2013) : 3448–55. http://dx.doi.org/10.1111/ejn.12346.

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Lee, Norman, Jessica L. Ward, Alejandro Vélez, Christophe Micheyl et Mark A. Bee. « Frogs Exploit Statistical Regularities in Noisy Acoustic Scenes to Solve Cocktail-Party-like Problems ». Current Biology 27, n^o 5 (mars 2017) : 743–50. http://dx.doi.org/10.1016/j.cub.2017.01.031.

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Nabokov, Alexander, Ivan Yaistkov et Alexander Chukarin. « THEORETICAL RESEARCH STUDIES OF REGULARITIES FORMATION OF ACOUSTIC CHARACTERISTICS FOR THREADING AND SPLINE SHAFT MILLING MACHINE ». Akustika, VOLUME 41 (2021) : 189–94. http://dx.doi.org/10.36336/akustika202141189.

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The research paper presents the theoretical studies results of noise generation during workpieces processing on threading and spline shaft milling machines. It is proposed the analytical dependence determining the sound pressure and sound power for various acoustic models of the noise sources with grounding conditions of the cutting tool, workpieces and their geometric dimensions.

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Rastegaev, I. A., et A. V. Polunin. « Regularities and features of acoustic emission under plasma electrolytic oxidation of wrought Al-Mg alloy ». Journal of Physics : Conference Series 2144, n^o 1 (1 décembre 2021) : 012020. http://dx.doi.org/10.1088/1742-6596/2144/1/012020.

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Abstract The paper highlights the characteristic features of acoustic emission (AE) in the process of plasma electrolytic oxidation (PEO) of aluminum alloy, and also reveals the correlation of 4 main stages of PEO process with AE signals. The fundamental possibility to establish and detail the features of oxidation stages and to compare different PEO modes by AE signals was demonstrated. The results obtained substantiate the high potential of AE method as an instrument of in situ research, production monitoring and control, and evaluation of quality of PEO process on aluminum alloys.

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Camarata, Stephen, et Jack Gandour. « Rule Invention in the Acquisition of Morphology by a Language-Impaired Child ». Journal of Speech and Hearing Disorders 50, n^o 1 (février 1985) : 40–45. http://dx.doi.org/10.1044/jshd.5001.40.

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This paper presents a case study of a language-impaired child who invented a unique morphophonologic rule for signaling the distinction between English singular and plural nouns. Conventional linguistic-phonetic analysis indicated that the child was producing the distinction suprasegmentally rather than segmentally. Acoustic-phonetic analysis of matched singular-plural noun pairs was performed in order to determine quantitatively which suprasegmental acoustic cues he used to signal the distinction. Results of a multivariate analysis of variance revealed that singular and plural productions were significantly different from one another on various fundamental frequency, duration, and intensity parameters. This example of a child's linguistic creativity is offered as further evidence in support of a model of language acquisition that emphasizes the cognitive aspects underlying linguistic regularities in child language. Clinical implications are also discussed.

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Wiener, Seth, Kiwako Ito et Shari R. Speer. « Early L2 Spoken Word Recognition Combines Input-Based and Knowledge-Based Processing ». Language and Speech 61, n^o 4 (21 mars 2018) : 632–56. http://dx.doi.org/10.1177/0023830918761762.

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This study examines the perceptual trade-off between knowledge of a language’s statistical regularities and reliance on the acoustic signal during L2 spoken word recognition. We test how early learners track and make use of segmental and suprasegmental cues and their relative frequencies during non-native word recognition. English learners of Mandarin were taught an artificial tonal language in which a tone’s informativeness for word identification varied according to neighborhood density. The stimuli mimicked Mandarin’s uneven distribution of syllable+tone combinations by varying syllable frequency and the probability of particular tones co-occurring with a particular syllable. Use of statistical regularities was measured by four-alternative forced-choice judgments and by eye fixations to target and competitor symbols. Half of the participants were trained on one speaker, that is, low speaker variability while the other half were trained on four speakers. After four days of learning, the results confirmed that tones are processed according to their informativeness. Eye movements to the newly learned symbols demonstrated that L2 learners use tonal probabilities at an early stage of word recognition, regardless of speaker variability. The amount of variability in the signal, however, influenced the time course of recovery from incorrect anticipatory looks: participants exposed to low speaker variability recovered from incorrect probability-based predictions of tone more rapidly than participants exposed to greater variability. These results motivate two conclusions: early L2 learners track the distribution of segmental and suprasegmental co-occurrences and make predictions accordingly during spoken word recognition; and when the acoustic input is more variable because of multi-speaker input, listeners rely more on their knowledge of tone-syllable co-occurrence frequency distributions and less on the incoming acoustic signal.

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Takegata, Rika, Petri Paavilainen, Risto Naatanen et Istvan Winkler. « Preattentive processing of spectral, temporal, and structural characteristics of acoustic regularities : A mismatch negativity study ». Psychophysiology 38, n^o 1 (janvier 2001) : 92–98. http://dx.doi.org/10.1111/1469-8986.3810092.

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Shkuratnik, V. L., S. V. Kuchurin et V. A. Vinnikov. « Regularities of acoustic emission and thermoemission memory effect in coal specimens under varying thermal conditions ». Journal of Mining Science 43, n^o 4 (juillet 2007) : 394–403. http://dx.doi.org/10.1007/s10913-007-0038-y.

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Sidlyar, Aleksandr, Boris Saksin, Marina Potapchuk, Vitaliy Usikov et Mikhail Lo-mov. « Analysis of activation features of geodynamic processes and formation of impact hazard at Nikolaevsk deposit ». E3S Web of Conferences 129 (2019) : 01019. http://dx.doi.org/10.1051/e3sconf/201912901019.

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Based on the results of a joint analysis of seismic-acoustic monitoring data and the geological and structural features of the Niko-laevsk deposit, the main regularities of the formation of technogenic stress fields that determine its impact hazard have been identified. Additionally, using the method of mathematical modeling, a study was done of the stress-strain state of the rock mass taking into account the tectonically ac-tive fault TD-3 and safety measures were proposed to reduce the impact hazard of the rock mass at the Nikolaevsk deposit.

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Nazarov V. E. et Kiyashko S. B. « Nonlinear acoustic effects in polycrystalline solids with saturation of amplitude-dependent internal friction ». Physics of the Solid State 64, n^o 8 (2022) : 916. http://dx.doi.org/10.21883/pss.2022.08.54694.365.

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Theoretical and numerical studies of nonlinear acoustic effects arising from the propagation of initially harmonic waves in polycrystalline solids with saturation of amplitude-dependent internal friction have been carried out. Two main types of hysteresis are considered: elastic and inelastic. A comparative analysis of the regularities of nonlinear effects is carried out and the characteristics of nonlinear quasi-harmonic waves in such media are determined: amplitude-dependent losses and changes in propagation velocity, as well as amplitudes of higher harmonics. A method for determining the type of polycrystal hysteresis based on the analysis of theoretical and experimentally established amplitude dependences of nonlinear effects is proposed. Keywords: elastic waves, amplitude-dependent internal friction.

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Rocchi, Francesca, et Ramnarayan Ramachandran. « Neuronal adaptation to sound statistics in the inferior colliculus of behaving macaques does not reduce the effectiveness of the masking noise ». Journal of Neurophysiology 120, n^o 6 (1 décembre 2018) : 2819–33. http://dx.doi.org/10.1152/jn.00875.2017.

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The detectability of target sounds embedded within noisy backgrounds is affected by the regularities that summarize acoustic sceneries. Previous studies suggested that the dynamic range of neurons in the inferior colliculus (IC) of anesthetized guinea pigs shifts toward the mean sound pressure level in irregular acoustic environments. Yet, it is unclear how this neuronal adaptation processes may influence the effectiveness of sounds as a masker, both behaviorally and in terms of neuronal encoding. To answer this question, we measured the neural response of IC neurons while macaque monkeys performed a Go/No-Go tone detection task. Macaques detected a 50-ms tone that was either simultaneously gated with a burst of noise or embedded within a continuous noise background, whose levels were randomly sampled (every 50 ms) from a probability distribution. The mean of the distribution matched the level of the gated burst of noise. Psychometric and IC neurometric thresholds to tones did not differ between the two masking conditions. However, the neuronal firing rate versus level function was significantly affected by the temporal characteristics of the noise masker. Simultaneously gated noise caused higher baseline responses and greater dynamic range compression compared with noise distribution. The slopes of psychometric and neurometric functions were significantly shallower for higher variance distributions, suggesting that neuronal sensitivity might change with the variability of the sound. Our results suggest that the adaptive response of IC neurons to sound regularities does not affect the effectiveness of the noise-masking signal, which remains invariant to surrounding noise amplitudes. NEW & NOTEWORTHY Auditory neurons adapt to the statistics of sound levels in the acoustic scene. However, it is still unclear to what extent such adaptation influences the effectiveness of the stimulus as a masker. Our study represents the first attempt to investigate how the adaptation to the statistics of masking stimuli may be related to the effectiveness of masking, and to the single-unit encoding of the midbrain auditory neurons in behaving animals.

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Kandrachuk, Ivan Viktorovych. « Аnalysis of regularities of formation of a plane acoustic wave fields with curvilinear cylindrical piezoceramic transducers ». Electronics and Communications 17, n^o 6 (28 février 2013) : 148–52. http://dx.doi.org/10.20535/2312-1807.2012.17.6.11411.

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Rasshcheplyaev, Yu S., et V. V. Khutortsev. « Using regularities of multiplication processes in problems of acoustic-emission testing of the strength of structures ». Russian Journal of Nondestructive Testing 43, n^o 8 (août 2007) : 542–48. http://dx.doi.org/10.1134/s1061830907080062.

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Callan, Daniel E., Ray D. Kent, Nelson Roy et Stephen M. Tasko. « Self-Organizing Map for the Classification of Normal and Disordered Female Voices ». Journal of Speech, Language, and Hearing Research 42, n^o 2 (avril 1999) : 355–66. http://dx.doi.org/10.1044/jslhr.4202.355.

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The goal of this research was to train a self-organizing map (SOM) on various acoustic measures (amplitude perturbation quotient, degree of voice breaks, rahmonic amplitude, soft phonation index, standard deviation of the fundamental frequency, and peak amplitude variation) of the sustained vowel /a/ to enhance visualization of the multidimensional nonlinear regularities inherent in the input data space. The SOM was trained using 30 spasmodic dysphonia exemplars, 30 pretreatment functional dysphonia exemplars, 30 post-treatment functional dysphonia exemplars, and 30 normal voice exemplars. After training, the classification performance of the SOM was evaluated. The results indicated that the SOM had better classification performance than that of a stepwise discriminant analysis over the original data. Analysis of the weight values across the SOM, by means of stepwise discriminant analysis, revealed the relative importance of the acoustic measures in classification of the various groups. The SOM provided both an easy way to visualize multidimensional data, and enhanced statistical predictability at distinguishing between the various groups (over that conducted on the original data set). We regard the results of this study as a promising initial step into the use of SOMs with multiple acoustic measures to assess phonatory function.

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Hernández-Fernández, Antoni, Iván G. Torre, Juan-María Garrido et Lucas Lacasa. « Linguistic Laws in Speech : The Case of Catalan and Spanish ». Entropy 21, n^o 12 (26 novembre 2019) : 1153. http://dx.doi.org/10.3390/e21121153.

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In this work we consider Glissando Corpus—an oral corpus of Catalan and Spanish—and empirically analyze the presence of the four classical linguistic laws (Zipf’s law, Herdan’s law, Brevity law, and Menzerath–Altmann’s law) in oral communication, and further complement this with the analysis of two recently formulated laws: lognormality law and size-rank law. By aligning the acoustic signal of speech production with the speech transcriptions, we are able to measure and compare the agreement of each of these laws when measured in both physical and symbolic units. Our results show that these six laws are recovered in both languages but considerably more emphatically so when these are examined in physical units, hence reinforcing the so-called ‘physical hypothesis’ according to which linguistic laws might indeed have a physical origin and the patterns recovered in written texts would, therefore, be just a byproduct of the regularities already present in the acoustic signals of oral communication.

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Traer, James, et Josh H. McDermott. « Statistics of natural reverberation enable perceptual separation of sound and space ». Proceedings of the National Academy of Sciences 113, n^o 48 (10 novembre 2016) : E7856—E7865. http://dx.doi.org/10.1073/pnas.1612524113.

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In everyday listening, sound reaches our ears directly from a source as well as indirectly via reflections known as reverberation. Reverberation profoundly distorts the sound from a source, yet humans can both identify sound sources and distinguish environments from the resulting sound, via mechanisms that remain unclear. The core computational challenge is that the acoustic signatures of the source and environment are combined in a single signal received by the ear. Here we ask whether our recognition of sound sources and spaces reflects an ability to separate their effects and whether any such separation is enabled by statistical regularities of real-world reverberation. To first determine whether such statistical regularities exist, we measured impulse responses (IRs) of 271 spaces sampled from the distribution encountered by humans during daily life. The sampled spaces were diverse, but their IRs were tightly constrained, exhibiting exponential decay at frequency-dependent rates: Mid frequencies reverberated longest whereas higher and lower frequencies decayed more rapidly, presumably due to absorptive properties of materials and air. To test whether humans leverage these regularities, we manipulated IR decay characteristics in simulated reverberant audio. Listeners could discriminate sound sources and environments from these signals, but their abilities degraded when reverberation characteristics deviated from those of real-world environments. Subjectively, atypical IRs were mistaken for sound sources. The results suggest the brain separates sound into contributions from the source and the environment, constrained by a prior on natural reverberation. This separation process may contribute to robust recognition while providing information about spaces around us.

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Назаров, В. Е., et С. Б. Кияшко. « Нелинейные акустические эффекты в поликристаллических твердых телах с насыщением амплитудно-зависимого внутреннего трения ». Физика твердого тела 64, n^o 8 (2022) : 927. http://dx.doi.org/10.21883/ftt.2022.08.52684.365.

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Theoretical and numerical studies of nonlinear acoustic effects arising from the propagation of initially harmonic waves in polycrystalline solids with saturation of amplitude-dependent internal friction have been carried out. Two main types of hysteresis are considered: elastic and inelastic. A comparative analysis of the regularities of nonlinear effects is carried out and the characteristics of nonlinear quasi-harmonic waves in such media are determined: amplitude-dependent losses and changes in propagation velocity, as well as amplitudes of higher harmonics. A method for determining the type of polycrystal hysteresis based on the analysis of theoretical and experimentally established amplitude dependences of nonlinear effects is proposed.

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Erofeev, V. I., A. V. Ilyahinskii, E. A. Motova, V. M. Rodyushkin et A. V. Shekoyan. « ON THE ACOUSTIC PARAMETERS OF METAL CONSTRUCTIONWHEN DAMAGE IS ACCUMULATED ». Problems of strenght and plasticity 83, n^o 3 (2021) : 344–53. http://dx.doi.org/10.32326/1814-9146-2021-83-3-344-353.

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In the work with the use of nondestructive control methods, the issues of determining acceptable durability or safe resource are considered. It is shown that the design monitoring procedure can be presented as follows: determines the original state zero zone, where the material of the product was subjected to low operational loads; further, with the use of nondestructive control methods, the acoustic parameter is measured (without disassembling the product)., such as the speed of elastic acoustic waves, nonlinear acoustic parameter, difference of velocities with twofrequency sensing, etc.; acoustic scanning of the product's metal is performed, in areas where there have been significant loads, signoff voltages, leading to an intensive accumulation of damage (the destruction of metal leading to cracks); defined zone “N” where the metal state parameter, for which the value is taken, characterizing the difference of the acoustic parameter (the speed of elastic waves, nonlinear acoustic parameter, the difference in velocity in twofrequency sensing) relative to the same parameter in the zone of zero exceeds the established level. The regularities established in the work linking the presence of plastic deformation with the difference in the delays (velocity) of elastic Rayleigh waves at different sounding frequencies at a fixed base between the emitter and the receiver of elastic waves, as well as the behavior of a nonlinear acoustic parameter during the safe resource time, suggest the possibility of using the observd fact as a principle for controlling the limiting state of the material due to plastic deformations on industrial structures. Based on the proposed approach, an engineering methodology for determining the technical condition of the material of the structures of production facilities is proposed, which allows to establish three stages of operation: the reliable operation mode; the controlled operation mode and the critical operation mode.

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Mooshammer, Christine, et Christian Geng. « Acoustic and articulatory manifestations of vowel reduction in German ». Journal of the International Phonetic Association 38, n^o 2 (22 juillet 2008) : 117–36. http://dx.doi.org/10.1017/s0025100308003435.

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Recent phonological approaches incorporate phonetic principles in the motivation of phonological regularities, e.g. vowel reduction and neutralization in unstressed position by target undershoot. So far, evidence for this hypothesis is based on impressionistic and acoustic data but not on articulatory data. The major goal of this study is to compare formant spaces and lingual positions during the production of German vowels for combined effects of stress, accent and corrective contrast. In order to identify strategies for vowel reduction independent of speaker-specific vocal-tract anatomies and individual biomechanical properties, an approach similar to the Generalized Procrustes Analysis was applied to formant spaces and lingual vowel target positions. The data basis consists of the German stressed and unstressed full vowels /iù ɪ yù ʏ eù ɛ ɛùφùœaù a où ɔ uù ʊ/ from seven speakers recorded by means of electromagnetic midsagittal articulography (EMMA). Speaker normalized articulatory and formant spaces gave evidence for a greater degree of coarticulation with the consonant context for unstressed vowels as compared to stressed vowels. However, only for tense vowels could spatial reduction patterns be attributed to vowel shortening, whereas lax vowels were reduced without shortening. The results are discussed in the light of current theories of vowel reduction, i.e. target undershoot, Adaptive Dispersion Theory and Prominence Alignment.

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Pedersen, Nicolai F., Torsten Dau, Lars Kai Hansen et Jens Hjortkjær. « Modulation transfer functions for audiovisual speech ». PLOS Computational Biology 18, n^o 7 (19 juillet 2022) : e1010273. http://dx.doi.org/10.1371/journal.pcbi.1010273.

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Temporal synchrony between facial motion and acoustic modulations is a hallmark feature of audiovisual speech. The moving face and mouth during natural speech is known to be correlated with low-frequency acoustic envelope fluctuations (below 10 Hz), but the precise rates at which envelope information is synchronized with motion in different parts of the face are less clear. Here, we used regularized canonical correlation analysis (rCCA) to learn speech envelope filters whose outputs correlate with motion in different parts of the speakers face. We leveraged recent advances in video-based 3D facial landmark estimation allowing us to examine statistical envelope-face correlations across a large number of speakers (∼4000). Specifically, rCCA was used to learn modulation transfer functions (MTFs) for the speech envelope that significantly predict correlation with facial motion across different speakers. The AV analysis revealed bandpass speech envelope filters at distinct temporal scales. A first set of MTFs showed peaks around 3-4 Hz and were correlated with mouth movements. A second set of MTFs captured envelope fluctuations in the 1-2 Hz range correlated with more global face and head motion. These two distinctive timescales emerged only as a property of natural AV speech statistics across many speakers. A similar analysis of fewer speakers performing a controlled speech task highlighted only the well-known temporal modulations around 4 Hz correlated with orofacial motion. The different bandpass ranges of AV correlation align notably with the average rates at which syllables (3-4 Hz) and phrases (1-2 Hz) are produced in natural speech. Whereas periodicities at the syllable rate are evident in the envelope spectrum of the speech signal itself, slower 1-2 Hz regularities thus only become prominent when considering crossmodal signal statistics. This may indicate a motor origin of temporal regularities at the timescales of syllables and phrases in natural speech.

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