Journal of Theoretical and Computational Acoustics最新文献

{"title":"Characterization and optimization of the angle dependent acoustic absorption of 2D infinite periodic surfaces of Helmholtz resonators","authors":"D. Garza-Agudelo, Vicente Cutanda Henríquez, C. Jeong, P. R. Andersen","doi":"10.1142/s2591728522500104","DOIUrl":"https://doi.org/10.1142/s2591728522500104","url":null,"abstract":"","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"51 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81418430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Experimental validations of reconstructed excitation forces acting inside a solid enclosure Part II: Interior Region","authors":"Yazhong Lu, Lingguang Chen, Pan Zhou, Sean F. Wu","doi":"10.1142/s2591728522500098","DOIUrl":"https://doi.org/10.1142/s2591728522500098","url":null,"abstract":"","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"15 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84832146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Efficient Mode-Coupling Calculation for Constant Depth Ocean with Range-Dependent Sound–Speed Fluctuation","authors":"Jungyong Park, Haesang Yang","doi":"10.1142/s2591728521500249","DOIUrl":"https://doi.org/10.1142/s2591728521500249","url":null,"abstract":"In this paper, a criterion for efficient coupled-mode matrix calculation in a constant depth ocean with range-dependent sound–speed fluctuation is proposed. The usual stepwise coupled mode requires high computational power to calculate the mode-coupling matrix at each interface of the range segment. To reduce the computational complexity, the criterion for selecting appropriate mode pairs, which strongly affects the mode-coupling matrix, is derived from perturbation theory. This criterion determines the effective range of the modal beat wavenumber. Numerical examples indicate that compared with the full calculation of the mode-coupling matrix, for the calculation using the proposed criterion, the computational complexity is significantly reduced, while the accuracies of the mode-coupling matrix and acoustic field are maintained.","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"76 1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90097577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Analyzing motorcycle low-frequency noise","authors":"Yazhong Lu, Lingguang Chen, Sean F. Wu, Jingyan Hu, Huijun Li","doi":"10.1142/s2591728522500050","DOIUrl":"https://doi.org/10.1142/s2591728522500050","url":null,"abstract":"This paper presents analyses of the 3D acoustic fields generated by motorcycles at very low frequencies (<inline-formula><mml:math display=\"inline\" overflow=\"scroll\"> <mml:mo>&lt;</mml:mo> <mml:mn>1</mml:mn><mml:mn>5</mml:mn><mml:mn>0</mml:mn></mml:math></inline-formula> Hz) at the idle speed and during sudden acceleration. Diagnosis and analyses of sound sources at low frequencies have always been a significant challenge because the directivity of low-frequency sound is very poor. To date, there are no research papers and/or reports that have demonstrated low-frequency sources localization and radiation patterns of any kind at high spatial resolution in 3D space. This study shows that by using sound viewer technologies, which include the passive sonic detection and ranging (SODAR), the Helmholtz equation least squares (HELS) method, advanced signal processing, denoising, etc., the locations of sound sources and visualization of the sound fields can be determined with high spatial resolution, even at frequencies below 150 Hz. In particular, the HELS method allows for reconstructing all the acoustic quantities, including the acoustic pressure, time-averaged acoustic intensity, time-averaged acoustic power on the source surfaces and in 3D space. The hardware needed consists of a 3D array with six free-field precision microphones with pre-amplifiers, a miniature wide-angle camera, an eight-channel digital signal processor and a laptop computer.","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"26 7","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138519858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"A Science Scandal that Culminated in Declaring the Ivory-billed Woodpecker (Campephilus principalis) Extinct","authors":"M. D. Collins","doi":"10.1142/s2591728522500074","DOIUrl":"https://doi.org/10.1142/s2591728522500074","url":null,"abstract":"The Ivory-billed Woodpecker (Campephilus principalis) is an ultra-elusive bird that has repeatedly been feared extinct only to be rediscovered during the past hundred years. An article that was featured on the cover of Science in 2005 announced the most recent rediscovery in Arkansas, which was the first report of this species by ornithologists in several decades. Another group of ornithologists reported a series of sightings in Florida the following year, but the issue became controversial when nobody managed to get close enough to an Ivory-billed Woodpecker for a long enough period of time to obtain the clear photo that is regarded as the standard form of evidence for documenting birds. In Louisiana and Florida, video footage was obtained during three encounters with distant birds that were identified in the field as Ivory-billed Woodpeckers. The videos show field marks, body proportions, flights, and other behaviors and characteristics that are consistent with the Ivory-billed Woodpecker but no other species of the region. The five most compelling events in the videos are the focus here, but several additional events are also discussed. During four of the most compelling events, the audio track contains sounds that are consistent with the Ivory-billed Woodpecker. Extensions of previous results include a size comparison and a wingspan estimate that are used to fortify the analysis of two videos from Louisiana. Takeoffs with deep and rapid wingbeats and loud ‘wooden’ wing sounds, which were overlooked during previous analysis of a video that was obtained in Florida, are consistent with an account by Tanner. Additional events in the Florida video are also discussed, including a sudden maneuver during a swooping flight that coincides with ‘spring-like’ sounds. This issue started to evolve into a science scandal when critics, who had become entrenched in the position that the Ivory-billed Woodpecker is extinct, used specious arguments to cause a long delay in the publication of evidence that should be sufficient to establish persistence. After openly targeting relatively weak evidence, critics avoided engaging in open discourse on the strongest evidence after it was finally published. Some of the leading science journals helped to enable the scandal by failing to provide diligent oversight and publishing biased reports on the status of this issue. The scandal culminated in a decision by the U.S. Fish & Wildlife Service to declare the Ivory-billed Woodpecker extinct, which was made in the absence of an open discourse on the strongest evidence and in the wake of an unprecedented spike in published reports of sightings during the searches in Arkansas, Florida, and Louisiana.","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84215837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"3D viscoelastic finite-difference analysis of the monopole acoustic logs in cylindrical coordinates","authors":"Yue Pan, Xiao He, Xiuming Wang","doi":"10.1142/s2591728522500062","DOIUrl":"https://doi.org/10.1142/s2591728522500062","url":null,"abstract":"","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"39 5 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88654365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Rationale for Publishing Open Access","authors":"A. Pierce","doi":"10.1142/s2591728522500037","DOIUrl":"https://doi.org/10.1142/s2591728522500037","url":null,"abstract":"Authors submitting scientific articles to journals now have the option of publishing their articles open access. This entails paying the publisher a fee that will insure that readers can download a pdf of the article without charge from an internet site. This option is of relatively recent vintage and has become recently somewhat popular among authors who desire their articles to be widely read. The history of the emergence of such an option is reviewed and arguments are given for its being used.","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76332290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Determining excitation forces acting on the interior surface of an enclosure. Part II: Numerical simulations","authors":"Pan Zhou, Sean F. Wu, Yazhong Lu","doi":"10.1142/s2591728522500025","DOIUrl":"https://doi.org/10.1142/s2591728522500025","url":null,"abstract":"Part II of this study presents numerical simulations of reconstructing the excitation forces acting on the interior surface of an enclosure, based on the vibroacoustic information collected in the exterior region. Various types of excitation forces such as distributed, line, and point forces are considered. Moreover, fluid loading inside the enclosure is considered in the numerical simulations. Analytical proofs show that fluid loading has no impact on excitation forces, but has significant impacts on structural vibrations. This is especially true when the density of fluid medium inside an enclosure is high. Results demonstrate that when excitation forces are continuous, the accuracy in reconstruction may be very high. When excitation forces contain abrupt changes or discontinuities, for example, line and point force, the accuracy in reconstruction may be significantly reduced. This is because many expansion terms are required to properly describe the discontinuities of excitations. On the other hand, discretization grids are fixed a priori. When fixed discretization grids are used together with an increasing number of expansion terms, aliasing may occur that may completely distort the reconstructed excitation forces.","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89742377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Determining excitation forces acting on the interior surface of an enclosure. Part I: Theory","authors":"Sean F. Wu, Pan Zhou, Yazhong Lu","doi":"10.1142/s2591728522500013","DOIUrl":"https://doi.org/10.1142/s2591728522500013","url":null,"abstract":"Part I of this paper presents analytic solutions for reconstructing the excitation forces that act on the interior surfaces of a finite solid rectangular enclosure with the fluid loading effect taken into consideration, given vibroacoustic data in the exterior region. The reason for selecting a simple structure is to facilitate the reconstruction of excitation forces. To validate these analytic solutions, we apply the reciprocity principle and demonstrate that when the resultant excitation forces are used to excite the enclosure from the inside, the same vibroacoustic responses in the exterior region in exterior region can be obtained. To illustrate this point, we consider the case in which the top panel of a rectangular box is connected to the side walls through simply-supported boundary conditions, and the rest surfaces are rigid. The top surface of this box may be excited into vibrations by any type of excitation forces from the inside with the fluid loading effect taken into consideration. Note that for arbitrarily shaped structures under arbitrary boundary conditions, numerical solutions can be obtained. Therefore, it is possible to determine the excitation forces acting inside an enclosure based on the vibroacoustic information collected in the exterior. The knowledge of the excitation forces is critically important, because it can lead to optimal mitigation strategies to mitigate undesirable noise and vibrations.","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"29 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75298454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Localizing Submerged Acoustic Sources Under Adverse Conditions","authors":"M. D. Collins, L. T. Fialkowski, J. Lingevitch","doi":"10.1142/s259172852230001x","DOIUrl":"https://doi.org/10.1142/s259172852230001x","url":null,"abstract":"This paper reviews various approaches for localizing submerged acoustic sources under adverse conditions. It is essential to obtain data of the highest possible quality when there are adverse conditions, such as uncertainties in the environment, source motion, and low signal-to-noise ratio. Focalization is an approach in which the source location and environmental parameters are treated as unknowns. Due to a parameter hierarchy in which source location outranks environmental parameters, there may be many realizations of the environment that bring the source into focus; the ambiguity in the environment can be an advantage if the primary objective is to localize the source. Environmental uncertainty is often associated with environmental complexity, which can be an advantage by reducing the ambiguity of the source location. Obtaining a high-quality estimate of the covariance matrix may be difficult when there is source motion, but the complexity of the received field from a moving source is another factor that can reduce ambiguity. It may be possible to localize a source that is buried in noise when an estimate of the noise covariance matrix is available. During the development of approaches for localizing submerged sources, much of the focus has been on one-dimensional vertical arrays. An extension of the multi-valued Bartlett processor to the case of a rectangular array was designed to take advantage of the extra dimension of the array and appears to have the potential to be the most powerful combination of hardware and signal processing to date.","PeriodicalId":55976,"journal":{"name":"Journal of Theoretical and Computational Acoustics","volume":"735 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85634095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}