Pub Date : 2023-07-20DOI: 10.24425/aoa.2022.142891
A. Brański, Romuald Kuras
The article extended the idea of active vibration reduction of beams with symmetric modes to beams with asymmetric modes. In the case of symmetric modes, the symmetric PZT (s-PZT) was used, and the optimization of the problem led to the location of the s-PZT centre at the point with the greatest beam curvature. In the latter case, the asymmetric modes that occur due to the addition of the point mass cause an asymmetric distribution of the bending moment and transversal displacement of a beam. In this case, the optimal approach to the active vibration reduction requires both new asymmetric PZT (a-PZT) and its new particular distribution on the beam. It has been mathematically determined that the a-PZT asymmetry point (a-point), ought to be placed at the point of maximum beam bending moment. The a-PZT asymmetry was found mathematically by minimizing the amplitude of the vibrations. As a result, it was possible to formulate the criterion of the maximum bending moment of the beam. The numerical calculations confirmed theoretical considerations. So, it was shown that in the case of asymmetric vibrations, the a-PZTs reduced vibrations more efficiently than the s-PZT.
{"title":"Asymmetrical PZT applied to active reduction of asymmetrically vibrating beam – semi-analytical solution","authors":"A. Brański, Romuald Kuras","doi":"10.24425/aoa.2022.142891","DOIUrl":"https://doi.org/10.24425/aoa.2022.142891","url":null,"abstract":"The article extended the idea of active vibration reduction of beams with symmetric modes to beams with asymmetric modes. In the case of symmetric modes, the symmetric PZT (s-PZT) was used, and the optimization of the problem led to the location of the s-PZT centre at the point with the greatest beam curvature. In the latter case, the asymmetric modes that occur due to the addition of the point mass cause an asymmetric distribution of the bending moment and transversal displacement of a beam. In this case, the optimal approach to the active vibration reduction requires both new asymmetric PZT (a-PZT) and its new particular distribution on the beam. It has been mathematically determined that the a-PZT asymmetry point (a-point), ought to be placed at the point of maximum beam bending moment. The a-PZT asymmetry was found mathematically by minimizing the amplitude of the vibrations. As a result, it was possible to formulate the criterion of the maximum bending moment of the beam. The numerical calculations confirmed theoretical considerations. So, it was shown that in the case of asymmetric vibrations, the a-PZTs reduced vibrations more efficiently than the s-PZT.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43251018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2022.142895
W. Rdzanek, K. Szemela
This study presents an analysis of the effect of the concentrated mass on the acoustic power and the resonant frequencies of a vibrating thin circular plate. The fluid-structure interactions and the acoustic wave radiation effect have been included. The eigenfunction expansion has been used to express the transverse displacement of the plate. The appropriate number of modes is determined approximately to achieve physically correct results. Then highly accurate results are obtained numerically. The radiated acoustic power has been used to determine the resonant frequencies. The introducing of the concentrated mass is justified by modelling the added mass of the moving component of the exciter.
{"title":"The effect of a concentrated mass on the acoustic power and the resonant frequencies of a circular plate","authors":"W. Rdzanek, K. Szemela","doi":"10.24425/aoa.2022.142895","DOIUrl":"https://doi.org/10.24425/aoa.2022.142895","url":null,"abstract":"This study presents an analysis of the effect of the concentrated mass on the acoustic power and the resonant frequencies of a vibrating thin circular plate. The fluid-structure interactions and the acoustic wave radiation effect have been included. The eigenfunction expansion has been used to express the transverse displacement of the plate. The appropriate number of modes is determined approximately to achieve physically correct results. Then highly accurate results are obtained numerically. The radiated acoustic power has been used to determine the resonant frequencies. The introducing of the concentrated mass is justified by modelling the added mass of the moving component of the exciter.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48812346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2021.139643
Łukasz Gorazd
The aim of the paper is to experimentally determine the scattering matrix S of an example reflective muffler of cylindrical geometry for Helmholtz number exceeding the plane wave propagation. Determining the scattering matrix of an acoustic systems is a new and increasingly used approach in the assessment of reduction of noise propagating inside duct-like elements of heating, ventilation and air conditioning systems (HVAC). The scattering matrix of an acoustic system provides all necessary information on the propagation of wave through it. In case of the analysed reflective silencer, considered as a two-port system, the noise reduction was determined by calculating the transmission loss parameter (TL) based on the scattering matrix ( S ). Measurements were carried out in two planes of the cross-section of pipes connected to the muffler. Thepaper presents results of the scattering matrix evaluation for the wave composed of the plane wave (mode (0,0)) and the first radial mode (0,1), each of which was generated separately using the self-designed and constructed single-mode generator. The gain of proceeding measurements for single modes stems from the fact that theoretically, calculation of the S -matrix does not require, as will be presented in the paper, calculation of the measurement data inverse matrix. Moreover, if single mode sound fields are well determined, it ensures error minimization. The presented measurement results refer to an example of a duct like system with a reflective muffler for which the scattering matrix S was determined. The acoustic phenomena inside such a system can be scaled by the parameter ka .
{"title":"Experimental Determination of a Reflective Muffler Scattering Matrix for Single-Mode Excitation","authors":"Łukasz Gorazd","doi":"10.24425/aoa.2021.139643","DOIUrl":"https://doi.org/10.24425/aoa.2021.139643","url":null,"abstract":"The aim of the paper is to experimentally determine the scattering matrix S of an example reflective muffler of cylindrical geometry for Helmholtz number exceeding the plane wave propagation. Determining the scattering matrix of an acoustic systems is a new and increasingly used approach in the assessment of reduction of noise propagating inside duct-like elements of heating, ventilation and air conditioning systems (HVAC). The scattering matrix of an acoustic system provides all necessary information on the propagation of wave through it. In case of the analysed reflective silencer, considered as a two-port system, the noise reduction was determined by calculating the transmission loss parameter (TL) based on the scattering matrix ( S ). Measurements were carried out in two planes of the cross-section of pipes connected to the muffler. Thepaper presents results of the scattering matrix evaluation for the wave composed of the plane wave (mode (0,0)) and the first radial mode (0,1), each of which was generated separately using the self-designed and constructed single-mode generator. The gain of proceeding measurements for single modes stems from the fact that theoretically, calculation of the S -matrix does not require, as will be presented in the paper, calculation of the measurement data inverse matrix. Moreover, if single mode sound fields are well determined, it ensures error minimization. The presented measurement results refer to an example of a duct like system with a reflective muffler for which the scattering matrix S was determined. The acoustic phenomena inside such a system can be scaled by the parameter ka .","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44229876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2022.142908
N. Mohammadi
In the current study, investigations are made to control the MB truck cabin interior noise by reducing noise in the transmission path. The main sources of cabin noise include the engine, exhaust system, air inlet system, driveline system, and tyres (especially at higher speeds). Furthermore, vibrations of the body and interior parts of the truck may significantly impact the overall in-cabin sound level. Noise is transmitted into the cabin via air (airborne noise) and cabin structure (structure-borne noise). In the noise treatment phase, noise transmission paths are considered. A viscoelastic layer damping material is used to reduce the vibration amplitude of the cabin back wall. The overall loss factor and vibration amplitude reduction ratio for the structure treated is calculated. Computational results are then compared with the values obtained by the experimental modal analysis results. Choosing the suitable material and thickness can significantly reduce the vibration amplitude. A sound barrier, silicon adhesive, and foam are also utilised for noise control in the transmission path. The effectiveness of the mentioned acoustic materials on cabin noise reduction is evaluated experimentally. The experimental SPL values are reported in the frequency range of 20 Hz–20 kHz based on a 1/3 octave filter. The experimental results show that using acoustics materials reduces the overall in-cabin sound level for a wide range of frequencies.
{"title":"Airborne and Structure-Borne Noise Control in the MB Truck Cabin Interior by the Noise Reduction in the Transmission Path","authors":"N. Mohammadi","doi":"10.24425/aoa.2022.142908","DOIUrl":"https://doi.org/10.24425/aoa.2022.142908","url":null,"abstract":"In the current study, investigations are made to control the MB truck cabin interior noise by reducing noise in the transmission path. The main sources of cabin noise include the engine, exhaust system, air inlet system, driveline system, and tyres (especially at higher speeds). Furthermore, vibrations of the body and interior parts of the truck may significantly impact the overall in-cabin sound level. Noise is transmitted into the cabin via air (airborne noise) and cabin structure (structure-borne noise). In the noise treatment phase, noise transmission paths are considered. A viscoelastic layer damping material is used to reduce the vibration amplitude of the cabin back wall. The overall loss factor and vibration amplitude reduction ratio for the structure treated is calculated. Computational results are then compared with the values obtained by the experimental modal analysis results. Choosing the suitable material and thickness can significantly reduce the vibration amplitude. A sound barrier, silicon adhesive, and foam are also utilised for noise control in the transmission path. The effectiveness of the mentioned acoustic materials on cabin noise reduction is evaluated experimentally. The experimental SPL values are reported in the frequency range of 20 Hz–20 kHz based on a 1/3 octave filter. The experimental results show that using acoustics materials reduces the overall in-cabin sound level for a wide range of frequencies.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47155962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2022.141649
P. Dziechcinski
The effect of the power amplifier on speech intelligibility in public address systems is often marginalised – i.e. it is assumed that it does not introduce significant signal distortion. This approach is justified when the linear range of the amplifier is used. The large crest factor of the speech signal and economic considerations mean that the amplifier also works in the non-linear range. In this paper, the effect of power amplifier distortion on the speech transmission index for public address systems (STIPA) is presented. In the first step, this influence was evaluated by measurements for Class AB and D amplifiers. Then, a computer model of the public address system based on the direct STIPA method, taking into account the non-linear properties of the amplifier, was proposed. Using the computer model, the optimum amplifier driving values were determined taking into account the reverberation time and interfering noise.
{"title":"Effect of Power Amplifier Distortion on the Speech Transmission Index for Public Address Systems","authors":"P. Dziechcinski","doi":"10.24425/aoa.2022.141649","DOIUrl":"https://doi.org/10.24425/aoa.2022.141649","url":null,"abstract":"The effect of the power amplifier on speech intelligibility in public address systems is often marginalised – i.e. it is assumed that it does not introduce significant signal distortion. This approach is justified when the linear range of the amplifier is used. The large crest factor of the speech signal and economic considerations mean that the amplifier also works in the non-linear range. In this paper, the effect of power amplifier distortion on the speech transmission index for public address systems (STIPA) is presented. In the first step, this influence was evaluated by measurements for Class AB and D amplifiers. Then, a computer model of the public address system based on the direct STIPA method, taking into account the non-linear properties of the amplifier, was proposed. Using the computer model, the optimum amplifier driving values were determined taking into account the reverberation time and interfering noise.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42391920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2020.135276
T. Gudra, D. Banasiak
One major problem in the design of ultrasonic transducers results from a huge impedance mismatch between piezoelectric ceramics and the loading medium (e.g. gaseous, liquid, and biological media). Solving this problem requires the use of a matching layer (or layers). Optimal selection of materials functioning as matching layers for piezoelectric transducers used in transmitting and receiving ultrasound waves strictly depends on the type of the medium receiving the ultrasound energy. Several methods allow optimal selection of materials used as matching layers. When using a single matching layer, its impedance can be calculated on the basis of the Chebyshev, DeSilets or Souquet criteria. In the general case, the typically applied methods use an analogy to a transmission line in order to calculate the transmission coefficient T . This paper presents an extension of transmission coefficient calculations with additional regard to the attenuation coefficients of particular layers. The transmission coefficient T is optimised on the basis of a genetic algorithm method. The obtained results indicate a significant divergence between the classical calculation methods and the genetic algorithm method.
{"title":"Optimal Selection of Multicomponent Matching Layers for Piezoelectric Transducers using Genetic Algorithm","authors":"T. Gudra, D. Banasiak","doi":"10.24425/aoa.2020.135276","DOIUrl":"https://doi.org/10.24425/aoa.2020.135276","url":null,"abstract":"One major problem in the design of ultrasonic transducers results from a huge impedance mismatch between piezoelectric ceramics and the loading medium (e.g. gaseous, liquid, and biological media). Solving this problem requires the use of a matching layer (or layers). Optimal selection of materials functioning as matching layers for piezoelectric transducers used in transmitting and receiving ultrasound waves strictly depends on the type of the medium receiving the ultrasound energy. Several methods allow optimal selection of materials used as matching layers. When using a single matching layer, its impedance can be calculated on the basis of the Chebyshev, DeSilets or Souquet criteria. In the general case, the typically applied methods use an analogy to a transmission line in order to calculate the transmission coefficient T . This paper presents an extension of transmission coefficient calculations with additional regard to the attenuation coefficients of particular layers. The transmission coefficient T is optimised on the basis of a genetic algorithm method. The obtained results indicate a significant divergence between the classical calculation methods and the genetic algorithm method.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43885551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2022.142899
M. Lashgari, M. Arab, Mohsen Nadjafi, Mojtaba Rafiee
The purpose of this study was to evaluate the psychoacoustic annoyance (PA) that the tractor drivers are exposed to, and investigate its effects on their brain signals during their work activities. To this aim, the sound of a garden tractor was recorded. Each driver’s electroencephalogram (EEG) was then recorded at five different engine speeds. The Higuchi method was used to calculate the fractal dimension of the brain signals. To evaluate the amount of acoustic annoyance that the tractor drivers were exposed to, a psychoacoustic annoyance (PA) model was used. The results showed that as the engine speed increased, the values of PA increased as well. The results also indicated that an increase in the Higuchi’s fractal dimension (HFD) of alpha and beta bands was due to the increase of the engine speed. The regression results also revealed that there was a high correlation between the HFD of fast wave activities and PA, in that, the coefficients of determination were 0.92 and 0.91 for alpha and beta bands, respectively. Hence, a good correlation between the EEG signals and PA can be used to develop a mathematical model which quantifies the human brain response to the external stimuli.
{"title":"Effect of psychoacoustic annoyance on EEG signals of tractor drivers","authors":"M. Lashgari, M. Arab, Mohsen Nadjafi, Mojtaba Rafiee","doi":"10.24425/aoa.2022.142899","DOIUrl":"https://doi.org/10.24425/aoa.2022.142899","url":null,"abstract":"The purpose of this study was to evaluate the psychoacoustic annoyance (PA) that the tractor drivers are exposed to, and investigate its effects on their brain signals during their work activities. To this aim, the sound of a garden tractor was recorded. Each driver’s electroencephalogram (EEG) was then recorded at five different engine speeds. The Higuchi method was used to calculate the fractal dimension of the brain signals. To evaluate the amount of acoustic annoyance that the tractor drivers were exposed to, a psychoacoustic annoyance (PA) model was used. The results showed that as the engine speed increased, the values of PA increased as well. The results also indicated that an increase in the Higuchi’s fractal dimension (HFD) of alpha and beta bands was due to the increase of the engine speed. The regression results also revealed that there was a high correlation between the HFD of fast wave activities and PA, in that, the coefficients of determination were 0.92 and 0.91 for alpha and beta bands, respectively. Hence, a good correlation between the EEG signals and PA can be used to develop a mathematical model which quantifies the human brain response to the external stimuli.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47405796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2022.141645
Khaled Baazi
The aim of this acoustic study is to analyse the phoneme [t ˙ ] produced by school children surgically operated on for the cleft palate or cleft lip, in order to examine their vocal characteristics, to provide speech therapists with numerous concrete analyses of voice and speech, to effectively support them and to prevent some serious outcomes on their psychological and academic development. The motivation for this study was mainly stemming from the difficulties that Algerian schoolchildren with clefts encounter in the pronunciation of this phoneme. To carry out the study, several acoustic parameters were investigated in terms of the fundamental frequency F 0 , the first three formants F 1 , F 2 , and F 3 , the energy E 0 , the Voice Onset Time (VOT), the durations [CV] and [V] of the subsequent vowel [a]. For the analysis, further important parameters in the field of pathological speech were deployed, namely the degree of disturbance of F 0 (jitter), the degree of disturbance of intensity (shimmer) and the HNR (Harmonics to Noise Ratio). Results revealed disturbance in the values of F 1 , F 2 , and F 3 and stability in the values of F 0 . Another important reported aspect is the increase in the value of the VOT due to the difficulties in controlling the plosives’ successive closure and release.
{"title":"An Acoustic Study of the Emphatic Occlusive [t] in School-Going Children with Cleft Palate or Cleft Lip","authors":"Khaled Baazi","doi":"10.24425/aoa.2022.141645","DOIUrl":"https://doi.org/10.24425/aoa.2022.141645","url":null,"abstract":"The aim of this acoustic study is to analyse the phoneme [t ˙ ] produced by school children surgically operated on for the cleft palate or cleft lip, in order to examine their vocal characteristics, to provide speech therapists with numerous concrete analyses of voice and speech, to effectively support them and to prevent some serious outcomes on their psychological and academic development. The motivation for this study was mainly stemming from the difficulties that Algerian schoolchildren with clefts encounter in the pronunciation of this phoneme. To carry out the study, several acoustic parameters were investigated in terms of the fundamental frequency F 0 , the first three formants F 1 , F 2 , and F 3 , the energy E 0 , the Voice Onset Time (VOT), the durations [CV] and [V] of the subsequent vowel [a]. For the analysis, further important parameters in the field of pathological speech were deployed, namely the degree of disturbance of F 0 (jitter), the degree of disturbance of intensity (shimmer) and the HNR (Harmonics to Noise Ratio). Results revealed disturbance in the values of F 1 , F 2 , and F 3 and stability in the values of F 0 . Another important reported aspect is the increase in the value of the VOT due to the difficulties in controlling the plosives’ successive closure and release.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44098818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biography and scientific achievements of Academician Leonid Maksimovich Brekhovskikh - Russian physicist, the founder of the scientific school of Ocean Acoustics, Doctor of Physics and Mathematics Sciences, Professor, Academician of the Russian Academy of Sciences.
{"title":"Chronicle: Academician Leonid Maksimovich Brekhovskikh – 100th Anniversary of the Birth","authors":"A. Serebryany","doi":"10.24425/123926","DOIUrl":"https://doi.org/10.24425/123926","url":null,"abstract":"Biography and scientific achievements of Academician Leonid Maksimovich Brekhovskikh - Russian physicist, \u0000the founder of the scientific school of Ocean Acoustics, Doctor of Physics and Mathematics Sciences, Professor, Academician of the Russian Academy of Sciences.","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46380578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.24425/aoa.2022.141659
{"title":"In Memoriam: Docent Janusz Renowski","authors":"","doi":"10.24425/aoa.2022.141659","DOIUrl":"https://doi.org/10.24425/aoa.2022.141659","url":null,"abstract":"","PeriodicalId":8149,"journal":{"name":"Archives of Acoustics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45678058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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