Journal articles: 'Acoustic analysis'

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okcu, selen. "Realism analysis of synthesized healthcare sound environments." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A182. http://dx.doi.org/10.1121/10.0015965.

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The acoustic qualities of healthcare sound environments can have significant influences on care providers’ ability to conduct critical sound tasks. Healthcare professionals constantly listen to the aural cues (e.g., alarms) and make critical decisions based on them. This study aims to assess the reliability of an open-source acoustical simulation tool in rendering healthcare providers’ auditory experience to enable the development of effective healthcare sound environments. The Pachyderm is developed as an open-source acoustical modeling and simulation plug-in for the Rhinoceros 3D-modeling platform commonly used by designers. The plug-in can compute various room acoustics metrics and generate auralizations by convolving anechoic recordings with the predicted acoustic signature of the architectural settings. While reliable predicted acoustic metrics are critical for iterative room-acoustics design studies, high fidelity auralizations can enable acoustic evaluations mainly based on critical listening and encourage collaboration between acoustical consultants, care providers and designers. The study introduces the findings of acoustic assessments including simulations and field measurements conducted in a new 14-bed adult medical-surgical inpatient unit at Milton S. Hershey Medical Center. The effectiveness is evaluated based on the deviation between the predicted and measured objective measures, and perceived differences between the auralizations and audio recordings assessed via listening tests.

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Masih, Dawa A. A., Nawzad K. Jalal, Manar N. A. Mohammed, and Sulaiman A. Mustafa. "The Assessment of Acoustical Characteristics for Recent Mosque Buildings in Erbil City of Iraq." ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY 9, no. 1 (March 1, 2021): 51–66. http://dx.doi.org/10.14500/aro.10784.

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The study of mosque acoustics, concerning acoustical features, sound quality for speech intelligibility, and additional practical acoustic criteria, is commonly overlooked. Acoustic quality is vital to the fundamental use of mosques, in terms of contributing toward prayers and worshippers’ appreciation. This paper undertakes a comparative analysis of the acoustic quality level and the acoustical characteristics for two modern mosque buildings constructed in Erbil city. This work investigates and examines the acoustical quality and performance of these two mosques and their prayer halls through room simulation using ODEON Room Acoustics Software, to assess the degree of speech intelligibility according to acoustic criteria relative to the spatial requirements and design guidelines. The sound pressure level and other room-acoustic indicators, such as reverberation time (T30), early decay time, and speech transmission index, are tested. The outcomes demonstrate the quality of acoustics in the investigated mosques during semi-occupied and fully-occupied circumstances. The results specify that the sound quality within the both mosques is displeasing as the loudspeakers were off.

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Autio, Hanna, Mathias Barbagallo, Carolina Ask, Delphine Bard Hagberg, Eva Lindqvist Sandgren, and Karin Strinnholm Lagergren. "Historically Based Room Acoustic Analysis and Auralization of a Church in the 1470s." Applied Sciences 11, no. 4 (February 10, 2021): 1586. http://dx.doi.org/10.3390/app11041586.

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Worship space acoustics have been established as an important part of a nation’s cultural heritage and area of acoustic research, but more research is needed regarding the region of northern Europe. This paper describes the historical acoustics of an important abbey church in Sweden in the 1470s. A digital historical reconstruction is developed. Liturgical material specific to this location is recorded and auralized within the digital reconstruction, and a room acoustic analysis is performed. The analysis is guided by liturgical practices in the church and the monastic order connected to it. It is found that the historical sound field in the church is characterized by the existence of two distinct acoustical subspaces within it, each corresponding to a location dedicated to the daily services of the monastical congregations. The subspaces show significantly better acoustic conditions for liturgical activities compared to the nave, which is very reverberant under the conditions of daily services. Acoustic transmission from the two subspaces is limited, indicating that the monastic congregations were visually and acoustically separated from the visitors in the nave and each other.

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Santika, Beta Bayu, Haram Lee, Yunjin Lee, and Jin Yong Jeon. "Psychophysiological responses to changes in the acoustic design of concert halls." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 268, no. 1 (November 30, 2023): 7154–59. http://dx.doi.org/10.3397/in_2023_1072.

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This study examined the psychophysiological responses of listeners to changes in the acoustic environment design of a concert hall. The research focused on both general audiences and experts in order to analyze the design of the acoustic environment based on their psychological and physiological aspects. The study involved the measurement of architectural acoustics of the hall and sound source produced through auralization based on the impulse responses collected earlier and the acoustical parameters gathered for the analysis. Changes were implemented through a refurbishment condition by the alterations to finishing materials. The objective sound environment improvement was evaluated by analyzing the electroencephalogram response in relation to the highly evaluated acoustic environment of the hall and the sound condition from the existing acoustic environment. The study found significant changes in the area related to emotion, preference for the acoustic environment, fatigue through the HRV parameter, and EEG. The results confirmed that psychophysiological responses to changes in the acoustical design provide an objective evidence of better concert hall acoustics.

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McCullah-Boozer, Megan R., Brooke M. Hinds, Logan T. Mathews, Mark C. Anderson, Michael Bassett, Lucas K. Hall, and Kent L. Gee. "A comparative analysis of rocket noise recordings from wildlife acoustic monitoring devices." Journal of the Acoustical Society of America 153, no. 3_supplement (March 1, 2023): A72. http://dx.doi.org/10.1121/10.0018204.

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Remote acoustic recorders are used in wildlife passive acoustical monitoring (PAM) and species identification. Such devices are designed to be relatively low-cost, user-friendly, weather-robust, and operate for extended periods with low maintenance. Usually, the precision of these devices is limited because most applications do not require high-fidelity measurements for typical wildlife PAM applications. However, the relatively low cost and flexibility of deployment beg the question if they can accurately record other noise sources, such as rocket launches. Such a situation calls for an evaluation of accuracy and a complete understanding of their capabilities and limitations. As such documentation is limited, this study seeks to characterize the acoustic performance of two commercially available wildlife acoustic monitoring devices: the Wildlife Acoustics SM-4 and the Cornell Ornithology Laboratory SwiftOne. We present acoustical results from a laboratory experiment and a field measurement of an orbital rocket launch. Comparisons to industry standard devices are made in the time and frequency domains and show the spectral characteristics of these devices. Recommendations are made regarding the use of these devices based on their performance.

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Kaselouris, Evaggelos, Chrysoula Alexandraki, Yannis Orphanos, Makis Bakarezos, Michael Tatarakis, Nektarios A. Papadogiannis, and Vasilis Dimitriou. "Acoustic analysis of impact sound on vibrating circular membranes." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 3 (August 1, 2021): 3378–85. http://dx.doi.org/10.3397/in-2021-2389.

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A finite element method (FEM) - boundary element method (BEM) model is developed to compute the sound generated by of a force acting on a circular membrane (drumhead). A vibro-acoustic analysis that combines modal FEM analysis, a FEM steady state dynamic analysis (SSD), considering harmonic loading and boundary element acoustics, is performed. The drumhead vibrates due to the force impact and the sound is emitted in the air. The vibration of structural response is initially computed, and the obtained results are set to be the boundary conditions of the acoustic analysis in the vibro-acoustic simulation. The radiated sound can be computed at any point of the solution domain. Various materials used by drumhead manufacturers are tested and a parametric analysis focusing on the mesh density of the models is presented. The impact sound and the acoustical characteristics of the simulated test cases are evaluated. The Rayleigh method is also applied to the acoustic simulations and is further compared to the BEM simulation results. The outcomes of this study may be further used as reverse engineering inputs, to machine learning models for the estimation of the physical and mechanical parameters of drumheads from audio signals.

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Wang, Guo, Yibin Wang, Yongzhi Min, and Wu Lei. "Blind Source Separation of Transformer Acoustic Signal Based on Sparse Component Analysis." Energies 15, no. 16 (August 19, 2022): 6017. http://dx.doi.org/10.3390/en15166017.

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In the acoustics-based power transformer fault diagnosis, a transformer acoustic signal collected by an acoustic sensor is generally mixed with a large number of interference signals. In order to separate transformer acoustic signals from mixed acoustic signals obtained by a small number of sensors, a blind source separation (BSS) method of transformer acoustic signal based on sparse component analysis (SCA) is proposed in this paper. Firstly, the mixed acoustic signals are transformed from time domain to time–frequency (TF) domain, and single source points (SSPs) in the TF plane are extracted by identifying the phase angle differences of the TF points. Then, the mixing matrix is estimated by clustering SSPs with a density clustering algorithm. Finally, the transformer acoustic signal is separated from the mixed acoustic signals based on the compressed sensing theory. The results of the simulation and experiment show that the proposed method can separate the transformer acoustic signal from the mixed acoustic signals in the case of underdetermination. Compared with the existing denoising methods of the transformer acoustic signal, the denoising results of the proposed method have less error and distortion. It will provide important data support for the acoustics-based power transformer fault diagnosis.

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Duran, Sebastian, Martyn Chambers, and Ioannis Kanellopoulos. "An Archaeoacoustics Analysis of Cistercian Architecture: The Case of the Beaulieu Abbey." Acoustics 3, no. 2 (March 26, 2021): 252–69. http://dx.doi.org/10.3390/acoustics3020018.

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The Cistercian order is of acoustic interest because previous research has hypothesized that Cistercian architectural structures were designed for longer reverberation times in order to reinforce Gregorian chants. The presented study focused on an archaeoacacoustics analysis of the Cistercian Beaulieu Abbey (Hampshire, England, UK), using Geometrical Acoustics (GA) to recreate and investigate the acoustical properties of the original structure. To construct an acoustic model of the Abbey, the building’s dimensions and layout were retrieved from published archaeology research and comparison with equivalent structures. Absorption and scattering coefficients were assigned to emulate the original room surface materials’ acoustics properties. CATT-Acoustics was then used to perform the acoustics analysis of the simplified building structure. Shorter reverberation time (RTs) was generally observed at higher frequencies for all the simulated scenarios. Low speech intelligibility index (STI) and speech clarity (C50) values were observed across Abbey’s nave section. Despite limitations given by the impossibility to calibrate the model according to in situ measurements conducted in the original structure, the simulated acoustics performance suggested how the Abbey could have been designed to promote sacral music and chants, rather than preserve high speech intelligibility.

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Zhang, Guo Jun, and Yun Ju Yan. "Applications of Statistical Energy Analysis in Influencing Factors Analysis of Aircraft Vibro-Acoustic Response Characteristics." Applied Mechanics and Materials 300-301 (February 2013): 810–13. http://dx.doi.org/10.4028/www.scientific.net/amm.300-301.810.

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The SEA model of hypersonic aircraft is established based on statistical energy analysis (SEA) theory. Three parameters of the SEA model are established by the theory and experiential formula. According to damping loss factors of model subsystem and acoustic absorptivity of cavity, sensitivity analysis of vibro-acoustic response is discussed. The effect that division way of plate subsystem and material structure cause to vibro-acoustic response is analyzed. The analysis results show that the material structure, damping loss factors and material type have the great effect on the characteristics of vibro-acoustic response. The division way of plate subsystem can affect computational accuracy greatly. The influencing factors should be synthetically considered in the design of acoustics structure.

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Marunin, Mikhail V., and Nataliya V. Polikarpova. "Polarization of Acoustic Waves in Two-Dimensional Phononic Crystals Based on Fused Silica." Materials 15, no. 23 (November 23, 2022): 8315. http://dx.doi.org/10.3390/ma15238315.

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The two-dimensional square-lattice phononic crystal is one of the recently proposed acoustic metamaterials. Strong anisotropic propagation of elastic waves makes the material promising for various potential applications in acoustics and acousto-optics. This paper presents a study of the propagation of elastic waves in two-dimensional phononic crystals based on fused silica. The band structures of a phononic crystal are obtained by solving the wave equation in its variational form by the finite element method. The main phononic crystal acoustic characteristics that are of practical interest in acousto-optics are calculated based on the analysis of the dispersion relations. It is shown that the choice of the phononic crystal geometry makes it possible to control the distributions of both the inverse phase velocities and the energy walk-off angles of acoustic modes. The calculations of the acoustic modes’ polarization are in a particular focus. It is demonstrated that under certain conditions, there are exactly three acoustic modes propagating in a phononic crystal, the averaged polarization vectors of which are mutually orthogonal for any directions of the acoustic wave’s propagation. It is argued that the acoustic properties of phononic crystals meet the requirements of acousto-optics.

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Zhou, Shu Wen, and Si Qi Zhang. "Structural-Acoustic Analysis of Automobile Passenger Compartment." Applied Mechanics and Materials 236-237 (November 2012): 175–79. http://dx.doi.org/10.4028/www.scientific.net/amm.236-237.175.

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Besides the performances of handling, stability, ride comfort, power and fuel economy, the sound pressure levels in the automobile passenger compartments heavily influence the customer’s purchasing decision. The interior acoustics of automobile passenger compartment was analyzed in this paper. The frequency response analysis was performed on the vehicle body due to road roughness. The frequency response of vehicle body’s output spectrum, nodes’ velocity is used as the boundary condition of the acoustic cavity. With boundary element method and acoustic transfer vector method, the panel acoustic contribution was analyzed. By modifying the stiffness, damping or mass of the corresponding panel, the acoustic pressure levels at the driver’s and passenger’s ear were decreased.

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Jalil, Nurul Amira Abd, Nazli Bin Che Din, and Nila Inangda Manyam Keumala Daud. "A Literature Analysis on Acoustical Environment in Green Building Design Strategies." Applied Mechanics and Materials 471 (December 2013): 138–42. http://dx.doi.org/10.4028/www.scientific.net/amm.471.138.

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Acoustic quality is important in ensuring a healthy and workable working environment. One of green buildings main objective is to reduce the building impact on human health and performance. This was emphasized in most green building rating system under its requirement for Indoor Environmental Quality (IEQ). IEQ highlights the four main points for achieving an improved indoor environment: indoor air quality, acoustics, visual comfort (lighting) and thermal comfort. Although acoustics was mentioned in the IEQ criteria, according to previous surveys and studies; acoustics quality in green buildings were not improving. It seems as though in order to improve on other green building criteria, acoustics performance is bound to become poorer. Through review of previous literature, survey and studies on acoustical performance in green buildings, the objective of this paper is to identify how green building design strategies contribute to the degradation of acoustical environment in green office buildings. Findings shows that design strategies implemented to cater for other green building requirements such as natural ventilation, daylight, reduction of finishes and office layout have unintentionally decrease the acoustical quality.

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Hovem, Jens M., and Hefeng Dong. "Understanding Ocean Acoustics by Eigenray Analysis." Journal of Marine Science and Engineering 7, no. 4 (April 25, 2019): 118. http://dx.doi.org/10.3390/jmse7040118.

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Acoustics is important for all underwater systems for object detection, classification, surveillance systems, and communication. However, underwater acoustics is often difficult to understand, and even the most carefully conducted measurements may often give unexpected results. The use of theory and acoustic modelling in support of measurements is very important since theory tends to be better behaved and more consistent than experiments, and useful to acquire better knowledge about the physics principle. This paper, having a tutorial flair, concerns the use of ray modelling and in particular eigenray analysis to obtain increased knowledge and understanding of underwater acoustic propagation.

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WALSH, TIMOTHY, GARTH REESE, CLARK DOHRMANN, and JERRY ROUSE. "FINITE ELEMENT METHODS FOR STRUCTURAL ACOUSTICS ON MISMATCHED MESHES." Journal of Computational Acoustics 17, no. 03 (September 2009): 247–75. http://dx.doi.org/10.1142/s0218396x0900394x.

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In this paper, a new technique is presented for structural acoustic analysis in the case of nonconforming acoustic–solid interface meshes. We first describe a simple method for coupling nonconforming acoustic–acoustic meshes, and then show that a similar approach, together with the coupling operators from conforming analysis, can also be applied to nonconforming structural acoustics. In the case of acoustic–acoustic interfaces, the continuity of acoustic pressure is enforced with a set of linear constraint equations. For structural acoustic interfaces, the same set of linear constraints is used, in conjunction with the weak formulation and the coupling operators that are commonly used in conforming structural acoustics. The constraint equations are subsequently eliminated using a static condensation procedure. We show that our method is equally applicable to time domain, frequency domain, and coupled eigenvalue analysis for structural acoustics. Numerical examples in both the time and frequency domains are presented to verify the methods.

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Griesinger, David H. "Acoustic analysis." Journal of the Acoustical Society of America 93, no. 4 (April 1993): 2256. http://dx.doi.org/10.1121/1.406647.

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Amran, M. Mohd, M. Shaiful Rizal, I. Maznan, Mohd Nazrul Roslan, Y. Musli Nizam, Mohd Imran Ghazali, and M. Shahruddin. "Evaluation of Sound Comfort in Examination Hall Using Acoustical Environmental Analyses." Applied Mechanics and Materials 315 (April 2013): 825–29. http://dx.doi.org/10.4028/www.scientific.net/amm.315.825.

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Acoustics environmental analyses were conducted in the unoccupied examination hall at Universiti Tun Hussein Onn Malaysia (UTHM), in order to determine the acoustical environment which reflects to sound comfort during sitting exam. The acoustic parameters that measured are background noise level, sound pressure level and reverberation time. The analysis result of untreated wall condition (without absorbent material) was revealed poor while treated wall condition (with absorbent material) revealed the improvement result. Installation of absorbent material on the wall and speakers rearrangement had reduced the highest background noise level of examination hall average reverberation times. A minor alteration at examination hall had contributed to better acoustic performance.

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Lai, Heather L., Anne C. Balant, and Chih-Yang Tsai. "Machine learning for analysis of wind farm noise." Journal of the Acoustical Society of America 155, no. 3_Supplement (March 1, 2024): A278. http://dx.doi.org/10.1121/10.0027495.

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Two challenges associated with analyzing acoustical data from wind farms are: 1) separating turbine sounds from environmental sounds and 2) classifying acoustical samples into different types of wind turbine noise based on acoustic characteristics. Machine-learning methods for classifying general environmental sounds have been developed using large human classified databases (e.g., YAMNet), but only a few studies have targeted classification of wind farm noise (WFN) specifically. Techniques for classifying wind farm noise have focused on identification of amplitude modulation (AM) using both traditional methods such as low frequency peak prominence (IOA method) and machine learning methods using both targeted AM acoustics features and more general deep acoustic features. To address these two challenges, we are developing a multi-echelon machine learning framework to identify and classify noise from wind farms using publicly available windfarm data and open-source software. The first echelon provides an automated method for identifying WFN samples that are free of environmental sounds. The second echelon uses machine learning to classify these wind farm noises according to the degree of AM, prominent tones, and other factors that might contribute to the human response and are incorporated in the metrics used or potentially used to assess compliance with regulations.

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Shi, Wen Ku, Guang Ming Wu, Zhi Yong Chen, and Nian Cheng Guo. "Prediction and Analysis of Vehicle Cab Interior Noise Based on Structure-Acoustic Coupling." Advanced Materials Research 424-425 (January 2012): 637–40. http://dx.doi.org/10.4028/www.scientific.net/amr.424-425.637.

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To study the vibration characteristics of the vehicle’s cab, finite element model of the cab was established and structural modal analysis was made. According to the internal structure of the cab, acoustic finite element modal of the cab including the seats was built and cavity acoustics modal analysis was carried out. Based on the structural modal and acoustic model of the cab, the coupled acoustic-structure model was carried. The acoustic response of the cab was calculated by mode-superposition

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Belsak, Ales, and Jurij Prezelj. "Acoustic Damage Analysis of a Gear System." Key Engineering Materials 488-489 (September 2011): 787–90. http://dx.doi.org/10.4028/www.scientific.net/kem.488-489.787.

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In diagnostics, noise can be a very reliable way of defining the condition of mechanical systems. There are different methods to visualise the noise source. Primarily, they deal with a specific noise source in a specific acoustic environment. This paper presents a visualization method of complex noise sources, using an acoustic camera. This method makes it possible to visualise all types of different complex noise sources; a special acoustic algorithm is applied for this purpose. Also, it is possible to observe various transient acoustical phenomena.

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Xu, Jie, Hui Li, You-Ling zhou, Qian Li, Liu-Xun Xue, Chong-Yue Shi, and Hou Wang. "Performance analysis of vortex acoustic wave based on uniform circular array." Journal of Physics: Conference Series 2078, no. 1 (November 1, 2021): 012069. http://dx.doi.org/10.1088/1742-6596/2078/1/012069.

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Abstract As a carrier for information and energy, acoustic waves have been applied in underwater communication widely, however, the narrow band and low transmission speed are the main problems. Whether in the field of optics or electromagnetic waves, the orbital angular momentum (OAM) represents the natural properties of the spiral phase structure. By introducing the OAM into the acoustics field, the transmission capacity and spectrum efficiency of the underwater acoustic communication system can be expanded. Based on the analysis and detection of the vortex acoustic wave generated by the circular array of transducers, we studied the array generation method of the spiral acoustic beam, and gave the characteristics of the vortex acoustic beam when propagating under the water. In the direction of the main axis, the uniform circular array was used to generate different topological acoustic vortex. To determine the relationship between the OAM topology mode and the transducer array, the spiral acoustic waves in different topology modes were generated, and the number of array elements, array radius, transmission frequency, etc. were investigated to give the effects on OAM acoustic vortex.

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Tronchin, Lamberto, and Antonella Bevilacqua. "3D Acoustic Map Analysis of the National Theatre of Zagreb." Applied Sciences 14, no. 11 (May 22, 2024): 4365. http://dx.doi.org/10.3390/app14114365.

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Rapid technological advances in recent decades have led researchers to refine the accuracy of their studies. In the field of acoustics, the impact of new devices is noticeable, especially in the investigations of cultural heritage buildings. The selection of a seat in theatres and concert halls has always been a concern, since the live experience of artistic performance depends on the quality of hearing and sight view. This paper deals with the elaboration of 360° acoustic maps made in the National Theatre of Zagreb, one of the opera theatres investigated with the Sipario project. The analysis of the main acoustic parameters has been carried out, starting with site measurements describing the acoustic response at various representative points of the main hall by covering the audience area. In addition, acoustic maps have been created for some selected positions based on a 3-degree-of-freedom (3dof) technique that allows a panoramic visualization of the impulse responses (IRs). This methodology completes the determination of early and late reflections that contribute to the acoustic quality of a place. In addition to the interest of experts in acoustics, this methodology can also be adopted by music lovers who can find a reasonable explanation for seat selection when booking their tickets.

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Deng, Jiang Hua, Jun Hong Dong, and Guang De Meng. "Sound Source Identification and Acoustic Contribution Analysis Using Nearfield Acoustic Holography." Advanced Materials Research 945-949 (June 2014): 717–24. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.717.

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The main goal of the present paper is to provide a method of source identification. Firstly, statistically optimal near-field acoustical holography (SONAH) techniques are applied to locate sound sources with the reflected sound field. In the presence of reflection plane parallel and perpendicular to the source plane, the incoming wave and reflected waves are separated based on the acoustic superposition principle and acoustic mirror image principle to satisfy the condition of the sound sources reconstruction using SONAH. Secondly, contribution of noise source to the special field point is analyzed and noise source ranking of interior panel groups are evaluated based the proposed three step acoustic contribution method. Finally, this method is verified experimentally.

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Xu, Guo Liang, Qi Wei He, Shao Chun Ding, and Hai Bo Wan. "Effects of Quay Wall and Seabed Reflection on the AUV Acoustic Radiation Test Analysis." Applied Mechanics and Materials 599-601 (August 2014): 922–26. http://dx.doi.org/10.4028/www.scientific.net/amm.599-601.922.

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To analyze effects of quay environment on the AUV radiated acoustic field test, the PNAH (PNAH: planar near-field acoustical holography) was used to simulate acoustic field. By simulating the free and non-free acoustic field and comparing amplitudes and angles of complex sound pressure, Analyze effects of quay wall and seabed reflection on the AUV radiated acoustic field test to determine the standard of quay wall and seabed environment which meets testing. The work would provide a certain reference for the AUV radiated acoustic field test.

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Shin, Sungjin, Geunhwan Kim, YoungSang Hwang, Juho Kim, and Youngmin Choo. "Effective feature fusion via analysis of quantitative similarity matrices among various acoustic features for underwater active target detection." Journal of the Acoustical Society of America 154, no. 4_supplement (October 1, 2023): A340. http://dx.doi.org/10.1121/10.0023731.

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For underwater active target detection, using conventional machine learning technique is limited and unsuitable because of small training data samples and diversity of environment. Therefore, to apply conventional machine learning for underwater acoustics target detection, three methodologies can be manipulated (1) feature, (2) architecture, and (3) learning strategy. In this paper, we implement various acoustic features in terms of feature similarity and feature fusion. From numerous studies in field of acoustics, various acoustic feature extraction methods have been proposed such as Mel-frequency cepstral coefficient, Gammatone-frequency cepstral coefficient, cepstral coefficient, short-time Fourier transform, constant Q transform, and wavelet packet decomposition. In this paper, we calculate a quantitative similarity between acoustic features by interpreting their data distributions with the corresponding probability densities in a reduced dimension. Furthermore, we fuse the acoustic features by simple concatenation. Fusion of a strongly correlated two-dimensional features tends to follow the performance of poor one, whereas the fusion of weakly correlated features improves performance remarkably. The performance improvement by the fusion of weakly correlated features is attributable to complementing acoustic information each other.

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Weyna, Stefan, Witold Mickiewicz, Michał Pyła, and Michał Jabłoński. "Experimental Acoustic Flow Analysis Inside a Section of an Acoustic Waveguide." Archives of Acoustics 38, no. 2 (June 1, 2013): 211–16. http://dx.doi.org/10.2478/aoa-2013-0025.

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Abstract Noise propagation within ducts is of practical concern in many areas of industrial processes where a fluid has to be transported in piping systems. The paper presents experimental data and visualization of flow in the vicinity of an abrupt change in cross-section of a circular duct and on obstacles inside where the acoustic wave generates nonlinear separated flow and vortex fields. For noise produced by flow wave of low Mach number, laminar and turbulent flows are studied us- ing experimental sound intensity (SI) and laser particle image velocimetry (PIV) technique adopted to acoustics (A-PIV). The emphasis is put on the development and application of these methods for better understanding of noise generation inside the acoustic ducts with different cross-sections. The intensity distribution inside duct is produced by the action of the sum of modal pressures on the sum of modal particle velocities. However, acoustic field is extremely complicated because pressures in non-propagating (cut-off) modes cooperate with particle velocities in propagating modes, and vice versa. The discrete frequency sound is strongly influenced by the transmission of higher order modes in the duct. By under- standing the mechanism of energy in the sound channels and pipes we can find the best solution to noise abatement technology. In the paper, numerous methods of visualization illustrate the vortex flow as an acoustic velocity or sound intensity stream which can be presented graphically. Diffraction and scattering phenomena occurring inside and around the open-end of the acoustic duct are shown.

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Liu, Wang Sheng, Ya An Li, Lin Cui, and Ming Huan Wang. "The Mutual Impedance Analysis of a Broadband Dense Plane Array." Advanced Materials Research 443-444 (January 2012): 1019–25. http://dx.doi.org/10.4028/www.scientific.net/amr.443-444.1019.

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Due to the mutual radiation impedance may influence acoustics performance of a broadband dense plane array seriously, the expression of mutual radiation impedance among the transducers is developed according to the definition of mutual radiation impedance based on BEM（Boundary Element Method）. BEM model is established for acoustic radiation of a broadband dense plane array with nine elements. Sound pressure distribution of the nine-element array is solved using SYSNOISE software. And mutual radiation impedances are calculated on the condition of knowing surface normal velocity. Acoustic performance of the nine-element array is analysed through mutual radiation impedance. The influence of mutual impedance on acoustics performance for nine-element array is verified by comparing with measured curve of transducer conductance. The results show that it is successful to calculate mutual impedance of the array and predict acoustics performance using BEM.

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Teixeira, João Paulo, Nuno Alves, and Paula Odete Fernandes. "Vocal Acoustic Analysis." International Journal of E-Health and Medical Communications 11, no. 1 (January 2020): 37–51. http://dx.doi.org/10.4018/ijehmc.2020010103.

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Vocal acoustic analysis is becoming a useful tool for the classification and recognition of laryngological pathologies. This technique enables a non-invasive and low-cost assessment of voice disorders, allowing a more efficient, fast, and objective diagnosis. In this work, ANN and SVM were experimented on to classify between dysphonic/control and vocal cord paralysis/control. A vector was made up of 4 jitter parameters, 4 shimmer parameters, and a harmonic to noise ratio (HNR), determined from 3 different vowels at 3 different tones, with a total of 81 features. Variable selection and dimension reduction techniques such as hierarchical clustering, multilinear regression analysis and principal component analysis (PCA) was applied. The classification between dysphonic and control was made with an accuracy of 100% for female and male groups with ANN and SVM. For the classification between vocal cords paralysis and control an accuracy of 78,9% was achieved for female group with SVM, and 81,8% for the male group with ANN.

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Rodrigues, Alfredo, Ashwin Dias, and Freddy Saddik. "Analysis, design, and installation of vibration isolation for lightweight helipads." Journal of the Acoustical Society of America 155, no. 3_Supplement (March 1, 2024): A333. http://dx.doi.org/10.1121/10.0027715.

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This case study discusses the design and manufacturing steps for the installation of a vibration isolation solution for two lightweight helidecks installed on the rooftop of an existing medical center building. The design stage involved the analysis of the relevant information, involving several specialties, such as Acoustics (for sources of vibration and acoustic performance requirements), Heliport Design[AR1] (for the type of aircraft, MTOW, number of supports, static and dynamic loads), and Structural (for the types of connections to the existing building structure). A collaborative effort between CDM Stravitec and the helideck supplier led the design through a progressive and iterative process where a final design that responded to the strong acoustical requirements and the complex nature of a fully functional and integrated lightweight helideck. Along the design, compromises where made ensure that requirements are met for both acoustic and structural performance. The solution delivered was a prefabricated box, which could easily be installed on site, comprised the necessary components, such as springs and uplift restraints to deal with the challenging aspects of the isolation of lightweight helidecks. The paper also discusses the challenges and best practices encountered during the production and installation of the system.

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Kawazoe, Yoshiyuki, and Hiroyuki Tanabe. "Acoustic Analysis for Urban Design Evaluation." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 268, no. 8 (November 30, 2023): 174–84. http://dx.doi.org/10.3397/in_2023_0043.

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Japanese townscapes have changed historically, and those changes have been inherited as distinctive streetscapes in various districts. This is a study that analyzes the characteristics of landscapes in each district based not on visual characteristics but on acoustic characteristics. Specifically, we analyzed the characteristics of each reverberation time and frequency in areas with historical landscapes such as Tsukishima and Nippori in Tokyo. We were able to grasp the finishing materials and architectural forms as acoustics, and were able to capture the characteristics of the street spaces in each city. We were able to verify the possibility as a method for evaluating urban design.

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Tang, Xiaoning, Xiansheng Zhang, Xingmin Zhuang, Huiping Zhang, and Xiong Yan. "Acoustical analysis of corduroy fabric for sound absorption: Experiments and simulations." Journal of Industrial Textiles 48, no. 1 (August 7, 2017): 201–20. http://dx.doi.org/10.1177/1528083717725912.

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Corduroy fabrics have been widely used in interior decoration currently. This work mainly investigated the acoustical properties of corduroy fabrics in relation to air permeability and airflow resistance. Five specimens with similar surface density and different wale width are used. The results indicated that corduroy fabrics with thicker wale width exhibited higher air permeability and lower airflow resistance. Furthermore, the increased width of wale is beneficial to improve the acoustic absorption of corduroy fabric. Two models based on air permeability and airflow resistance are taken to characterize the acoustical behavior. It has been indicated that Pieren model could well predict the acoustic absorption coefficient of corduroy fabric, and the difference of acoustic absorption is due to the varied air permeability and airflow resistance resulting from the different wale width.

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Hayashi, Takuro, Akihiko Enamito, Yuzo Yoshida, and Ryoichi Takahashi. "Structure-Acoustic Coupled Analysis using Acoustic Modal Analysis Method. Acoustic Field Analysis on Magnetic Resonance Imaging System." Transactions of the Japan Society of Mechanical Engineers Series C 60, no. 571 (1994): 856–61. http://dx.doi.org/10.1299/kikaic.60.856.

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Yan, Jin, Jiangfeng Li, Lvlong Zou, Dapeng Zhang, Cheng Wang, and Zhi Tang. "Acoustic Characteristics Analysis of Double-Layer Liquid-Filled Pipes Based on Acoustic–Solid Coupling Theory." Applied Sciences 13, no. 19 (October 6, 2023): 11017. http://dx.doi.org/10.3390/app131911017.

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Based on the theory of acoustic–solid coupling, the phase velocity-thickness product of a double-layer liquid-filled pipeline is analyzed, and the dispersion relationship between angular frequency and wavenumber–thickness product is analyzed, providing a theoretical basis for ultrasonic guided wave detection. The wave number analytical expression of the double-layer liquid-filled pipeline is constructed, and the dispersion relationship of the double-layer liquid-filled pipeline under different frequency–thickness products and wavenumber–thickness products is calculated through parameter scanning. The dispersion curves of the double-layer liquid-filled pipeline are numerically analyzed in the domains of pressure acoustics, solid mechanics, and acoustic–solid coupling. The numerically simulated dispersion curves show high consistency with the analytically calculated dispersion curves. The analysis of the phase velocity frequency–thickness product indicates that the axial mode dispersion curves of the pipe wall decrease with the increase in frequency–thickness product in the coupling domain, and then tend to be flat and intersect with the radial mode dispersion curves in the coupling domain; these intersection points cannot be used for ultrasonic guided wave detection. The T(0,1) mode dispersion curve in the coupling domain of the pressure acoustics domain remains smooth from low frequency to high frequency. It is found that the dispersion curves of the phase velocity frequency–thickness product, angular frequency wavenumber–thickness product, and the acoustic pressure distribution map of the double-layer liquid-filled pipeline based on acoustic–solid coupling can provide theoretical support for ultrasonic guided wave detection of pipelines.

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Holik, John, Tuende Szalay, Duy D. Nguyen, and Catherine Madill. "Advancing acoustical analysis: A suite of acoustic research-level measurement tools for professional and clinical applications." Journal of the Acoustical Society of America 154, no. 4_supplement (October 1, 2023): A59. http://dx.doi.org/10.1121/10.0022791.

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This presentation showcases the work of our research group in developing a suite of research-level acoustic measurement tools aimed at bridging the gap between cutting-edge research and practical applications clinical settings. Over the last four years over 100 Speech language Pathologists and Ear, Nose and Throat surgeons internationally have completed our course “Using acoustic analysis to assess and treat voice disorders in clinical and research settings.” This course has focused on advanced acoustic measurement techniques with a freeware (PRAAT) for specific application to voice disorder. The online course offers a one-stop shop for clinicians, providing access to state-of-the-art acoustic quantification methods that were previously restricted to the research domain. Detailed manuals and video walk-throughs ensure users can confidently navigate the measurement process and produce reliable acoustic data for clinical use. We are now planning to expand the range of courses in clinical and research-level acoustical analysis using other freeware applications and applications in other disciplines such as speech, accent and articulation analysis. This presentation will highlight the features and capabilities of our planned suite of research-level acoustic measurement tools, emphasising the translational impact they can have on enhancing acoustical analysis in various fields.

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Brentner, Kenneth S. "Direct numerical calculation of acoustics: solution evaluation through energy analysis." Journal of Fluid Mechanics 254 (September 1993): 267–81. http://dx.doi.org/10.1017/s0022112093002125.

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The propagation of acoustic energy from a sound source to the far field is a fundamental problem of acoustics. In this paper the use of computational fluid dynamics (CFD) to directly calculate the acoustic field is investigated. The two-dimensional, compressible, inviscid flow about an accelerating circular cylinder is used as a model problem. The time evolution of the energy transfer from the cylinder surface to the fluid, as the cylinder is moved from rest to some non-negligible velocity, is shown. Energy is the quantity of interest in the calculations since various components of energy have physical meaning. By examining the temporal and spatial characteristics of the numerical solution, a distinction can be made between the propagating acoustic energy, the convecting energy associated with the entropy change in the fluid, and the energy following the body. In the calculations, entropy generation is due to a combination of physical mechanisms and numerical error. In the case of propagating acoustic waves, entropy generation seems to be a measure of numerical damping associated with the discrete flow solver.

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Ramírez, David, Sergio Castiñeira-Ibáñez, Jose Maria Bravo-Plana-Sala, Juan Vicente Sánchez-Pérez, and Rubén Picó. "Analysis of the interaction of helmholtz resonators in periodic acoustic metamaterials depending on its orientation with the acoustic source." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 6 (August 1, 2021): 215–26. http://dx.doi.org/10.3397/in-2021-1369.

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Acoustic screens based on sonic crystals constitute one of the most promising technological bets of recent years in the field of environmental acoustics. Sonic crystals are defined as new materials formed by arrays of acoustic scatterers embedded in air. The design of these screens is made using powerful simulation models that provide reliable results without the need of expensive experimental testing. This project applies the finite elements method in order to analise an acoustic barrier that includes (Helmholtz) resonators in its scatterers, and studies the interference of the sonic crystal with the effect of the Helmholtz resonator, depending on its orientation with the acoustic source.

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CREȚU, Alina-Elena. "FACADE OF PERFORATED PLATE: ANALYSIS OF ITS ACOUSTIC BEHAVIOR." SCIENTIFIC RESEARCH AND EDUCATION IN THE AIR FORCE 18, no. 1 (June 24, 2016): 317–22. http://dx.doi.org/10.19062/2247-3173.2016.18.1.43.

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37

Park. "Analysis of the Acoustic Performance of Classrooms in Korea." Journal Of The Acoustical Society Of Korea 33, no. 5 (2014): 316. http://dx.doi.org/10.7776/ask.2014.33.5.316.

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YAMADA, Keisuke. "Coupled vibration analysis of structural-acoustic and acoustic-acoustic coupling systems." Proceedings of the Dynamics & Design Conference 2016 (2016): 342. http://dx.doi.org/10.1299/jsmedmc.2016.342.

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Trenkel, Verena M., Nils Olav Handegard, and Thomas C. Weber. "Observing the ocean interior in support of integrated management." ICES Journal of Marine Science 73, no. 8 (July 31, 2016): 1947–54. http://dx.doi.org/10.1093/icesjms/fsw132.

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Abstract Active- and passive-acoustic methods are widely used tools for observing, monitoring, and understanding marine ecosystems. From 25 to 28 May 2015, 214 scientists from 31 nations gathered for an ICES symposium on Marine Ecosystem Acoustics (SoME Acoustics) to discuss three major themes related to acoustic observations of marine ecosystems: (i) recent developments in acoustic and platform technologies; (ii) acoustic characterisation of aquatic organisms, ecosystem structure, and ecosystem processes; and (iii) contribution of acoustics to integrated ecosystem assessments and management. The development of, and access to new instruments, such as broad bandwidth systems, enables insightful ecological studies and innovative management approaches. Unresolved ecological questions and the increasing move towards ecosystem based management pose further challenges to scientists and instrument developers. Considering the SoME Acoustics presentations in the context of three previous ICES symposia on fisheries acoustics, topics increasingly emphasize ecosystem studies and management. The continued expansion of work and progress in marine ecosystem acoustics is due to the cross-disciplinary work of fisheries acousticians, engineers, ecologists, modellers, and others. An analysis of the symposium co-authorship network reveals a highly connected acoustic science community collaborating around the globe.

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Majeed, Ishrat, and Er Jasdeep Singh. "Design and Performance Analysis of Underwater Acoustic Sensor Networks." International Journal for Research in Applied Science and Engineering Technology 10, no. 3 (March 31, 2022): 294–303. http://dx.doi.org/10.22214/ijraset.2022.40599.

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Abstract: The underwater acoustic sensor network (UASN) is essential for exploration missions and observation in demanding environments. The UASN'S connection route is acoustic waves, which limits its usefulness in comparison to ground sensor networks. This is the case because to its limited capacity, latency, and significant route loss. This article provides comprehensive research of the characteristics of UASN. We explore the functionality of underwater acoustic ad-hoc networks in the presence of disruptions. RF signals are used as a communication mechanism in wireless sensor networks, both terrestrial and aerial. However, in a sub-sea setting, such as deep-sea research, detecting and transmitting data needs a completely different method to underwater communication. The fact that the seas cover 70% of the earth's surface and contain massive amounts of unexplored riches cannot be ignored. The aquatic environment has largely escaped the effects of recent breakthroughs in wireless sensor networks (WSNS) and their broad application in latest studies and economic progress. Research on underwater acoustic sensor networks (UASNS) is developing at a snail's pace due to the difficulties in transferring most of the state-of-the-art of land and air based WSNS to its aquatic equivalent. The bulk of underwater activities rely on acoustic communication and specialized sensors that can endure the harsh environment of the oceans. The purpose of this study is to investigate how UASN works in different situations. End-to-end latency and energy consumption are examined in response to a variety of factors. We also investigate how well underwater acoustic ad-hoc networks perform when nodes are dispersed, and the network is large. Keywords: Under water Acoustics, Sensor, Wireless Sensor Networks, Energy Consumptions.

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41

Leete, Kevin M., Kent L. Gee, Junhui Liu, and Alan T. Wall. "Near-field acoustical holography and acoustic power analysis of a simulated, highly heated supersonic jet." Journal of the Acoustical Society of America 151, no. 3 (March 2022): 1989–2001. http://dx.doi.org/10.1121/10.0009827.

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Although near-field acoustical holography (NAH) and acoustic intensity analysis have previously been used to investigate the apparent jet noise sources produced by military aircraft, explicit connections to supersonic jet characteristics cannot be made due to a lack of information about the exhaust plume. To begin to bridge this gap and better understand the source information yielded by NAH, the current study instead applies NAH to a virtual measurement of the near-field pressures of a highly heated laboratory-scale supersonic jet generated by large-eddy simulation (LES). The holographic reconstructions of the pressure, particle velocity, and acoustic intensity are found to match the LES-generated acoustic field well and are used to calculate the acoustic power of the jet. The jet's calculated overall acoustic power is compared to the free-stream mechanical power, resulting in an acoustic efficiency of 1.5%. Ray-tracing of the acoustic intensity to the jet centerline generates an axial distribution of the acoustic power origin, showing that almost all the power originates from the supersonic portion of the flow and with the distribution peak upstream of the potential core tip. Holographic reconstruction of the pressures along the nozzle lipline captures the general spectral shape of the LES-generated pressures, though it underestimates the amplitude.

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42

Wen, Qingwei. "Fourier transformation for acoustic: Principle & applications." Theoretical and Natural Science 10, no. 1 (November 17, 2023): 115–22. http://dx.doi.org/10.54254/2753-8818/10/20230326.

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A The Fourier transform has a wide range of applications in daily life, including physics, signal processing, acoustics etc. The topic of this article is to demonstrate the principle and applications of the Fourier transform in acoustics through theoretical derivation. The paper first derived the basic formula of the Fourier Transform and the related seven theorems. Then the paper detailed the research of Fourier Transform in underwater acoustic pulse signal detection technology. Finally, the application of Fourier Transform in the defect detection algorithm of MEMS acoustic films was detailed. According to the analysis, the paper demonstrated the primary application of Fourier Transform in underwater acoustic pulse signal detection and defect detection algorithm of MEMS acoustic film. Based on the evaluations, this study demonstrated the general application scenario of Fourier Transform and offered theoretical basis of its application in acoustic field, which promotes its developmental potential in the acoustic field. Overall, these results shed light on guiding further exploration of acoustic research.

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Burgos Pintos, Álvaro, Pedro Francisco Mayuet, María Alonso Gracía, and Lucía Rodríguez-Parada. "Methodology for the Acoustic Analysis of Acoustic Guitar Top Plates Designs by Additive Manufacturing." Key Engineering Materials 956 (September 29, 2023): 71–79. http://dx.doi.org/10.4028/p-3l0hgi.

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Nowadays, tools such as Additive Manufacturing (AM) contribute directly to an increase in the value of Industrial Design through the development of new products focused on customization. Specifically, the acoustic guitar is a good example of this, because it is a complex product to study due to the great variety of possible designs depending on the materials and the way they are obtained, which has repercussions on the final sound of the instrument. Due to the above, this paper develops a methodology for the study of the acoustic response depending on the design of an acoustic guitar using AM with Polylactic Acid (PLA) material. The methodology is divided into two types of tests: an acoustic test to capture the frequencies emitted by transmitting a sweep of frequencies across the audible spectrum to the soundboard, and another to visualize the vibrational patterns at five specific harmonic frequencies of the guitar by analyzing the movement of the soundboard and the influence of the bracing. This second test includes the PLA designed top with a reinforcement structure in its soundboard and a case in order to compare this design with a wooden guitar of the same size whose top has no reinforcement at all. From the tests carried out, it can be seen that the acoustics recorded by a top made of PLA can provide a good acoustic response compared to a wooden guitar, giving the possibility to create customized guitars according to the musician's tastes.

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Song, In-Jin, Jung-Ho Kim, Moo-Joon Kim, Kang-Lyeol Ha, and Noriyoshi Chubachi. "Analysis of Acoustic Fields from Acoustic Convex Lens." Japanese Journal of Applied Physics 43, no. 5B (May 28, 2004): 3059–60. http://dx.doi.org/10.1143/jjap.43.3059.

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45

Sandberg, Göran E., Per-Anders Hansson, and Mats Gustavsson. "Domain decomposition in acoustic and structure–acoustic analysis." Computer Methods in Applied Mechanics and Engineering 190, no. 24-25 (March 2001): 2979–88. http://dx.doi.org/10.1016/s0045-7825(00)00377-7.

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NAGAMI, Tadashi, Takayuki MIYAKAWA, and Toshio ENOMOTO. "Acoustic Analysis and Experimental Validation of Acoustic Metamaterial." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 268, no. 5 (November 30, 2023): 3015–24. http://dx.doi.org/10.3397/in_2023_0436.

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In this study, a unique sound insulation performance of a lightweight acoustic metamaterial consisting of a stiff honeycomb plate coated with a thin rubber membrane was experimentally demonstrated. An acoustic transmission measurement of the acoustic metamaterial showed that the sound insulation performance of the acoustic metamaterial exceeded the mass law predicted performance in three frequency ranges. An analysis of the acoustic-structure interaction revealed that these unique sound insulation phenomena were due to the cancellation between two high-order eigenmodes of the periodic structure or a high-order eigenmode of the periodic structure and an eigenmode of the membrane in each honeycomb cell. Subsequently, a prototype of this acoustic metamaterial was applied to a vehicle and its effectiveness on vehicle interior noise was investigated. The results show that such materials can further improve the level of quietness with weight reduction in vehicles and other transportation applications.

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Minin, Igor V., and Oleg V. Minin. "Comment on Mahariq et al. Investigation and Analysis of Acoustojets by Spectral Element Method. Mathematics 2022, 10, 3145." Mathematics 10, no. 23 (November 29, 2022): 4502. http://dx.doi.org/10.3390/math10234502.

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The paper under discussion has some shortcomings in regard to mathematical formulation of the problem related to acoustics, its justification, some references analyses and the text, and we feel that this study has not been finished to its full extent. From the point of view of acoustic jet formation, the mathematical model used by the authors has a number of significant limitations which are not taken into account. Moreover, the formal analogy between the parameters of electromagnetic waves and acoustic waves should be used with caution in the conditions of localized beams (acoustic jet), and the limits of their application should be justified.

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Kamisiński, Tadeusz, Krzysztof Brawata, Adam Pilch, Jarosław Rubacha, and Marcin Zastawnik. "Sound Diffusers with Fabric Covering." Archives of Acoustics 37, no. 3 (November 1, 2012): 317–22. http://dx.doi.org/10.2478/v10168-012-0040-5.

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Abstract Fabric covering is often used by designers, as it can easily mask acoustic structures that do not match an interior. However, in the case of sound diffusers based on change in the phase of the reflected wave, the use of fabric covering is not without its effect on acoustics. It reduces the effectiveness of these structures and raises acoustic absorption. In the paper, the authors analyzed the acoustical properties of a selected fabric used to cover sound diffusers. Sound absorption and scattering coefficients for a system composed of sound diffusers and a fabric situated at different distances d were measured. The results were compared to the sound absorption predicted on the basis of Kuttruff’s and Mechel’s theoretical models. Analysis of the results indicates that the fabric has a significant influence on the system’s acoustic parameters. It is also observed, that fabric applied directly on a phase grating diffuser, produces higher absorption than when it is at some distance from it.

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Danner, Gregory. "The Use of Acoustic Measures of Dissonance to Characterize Pitch-Class Sets." Music Perception 3, no. 1 (1985): 103–22. http://dx.doi.org/10.2307/40285324.

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Recent scholarship in acoustics has provided a mathematical model for the approximation of what has been termed "acoustic dissonance," or "roughness" in the interaction of two or more simultaneously sounded complex tones. Although these measures necessitate certain artificial considerations in their present form (i. e., spectrum, dynamics), their application should be of considerable interest to musical scholars interested in this aspect of musical style and structure. This article provides an overview of the acoustical theory, its application in profiling pitch-class sets, and a representative musical analysis.

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Gu, Lin Ning, and Nan Chen. "Coupling Acoustic Analysis of Enclosure Consisting of Multi-Flexible Plates and its Active Structural Acoustic Control." Applied Mechanics and Materials 50-51 (February 2011): 343–47. http://dx.doi.org/10.4028/www.scientific.net/amm.50-51.343.

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This paper develops a model of structural-acoustic coupled system of a rectangular enclosure involving two simply supported flexible plates. The acoustical potential energy and the optimal secondary control forces are derived theoretically. An example is presented to analyze the characteristics of the coupled system, the dominant factors that impact the coupling effects and the noise reduction with ASAC method. The paper shows the possibility of applying distributed cooperative control method to the structural-acoustic coupled system.

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Journal articles on the topic 'Acoustic analysis'

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