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Observations of spatial coherence from a multibeam sub-bottom profiler

Proceedings of Meetings on acoustics 2024年第1期54卷

作者： Laura Brownstead Jason Philtron Chad Smith Daniel C. Brown Graduate Program in Acoustics The Pennsylvania State University University Park PA Applied Research Laboratory The Pennsylvania State University University Park PA 16802 USA lgb5113@psu.edu Applied Research Laboratory The Pennsylvania State University University Park 16802 PA USA jhb186@psu.edu cms561@psu.edu dcb19@psu.edu

Sonar data from the Kongsberg SBP-29 (with a 64-channel receive array) aboard R/V Sally Ride is analyzed to judge the value of spatial coherence of signals reflected from the ocean floor. The multibeam sub-bottom profiler collected five days of sonar test data off the coast of Southern California over a variety of sediment types and marine geologies. The spatial coherence of measured signals is sensitive to different bottom types and to sediment layering deep below the ocean floor. Navigational data also permits comparison of sonar data to existing bathymetric maps of the ensonified floor. The flexibility of the transmit and receive arrays permit detailed study of potentially informative seafloor features and landmarks. The findings of primary interest are interpreted in the context of a Normal fit to characterize the spatial coherence of scattered signals and future work is reported based on statistical analysis of the fitted data.

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Photoacoustic measurement of the optical absorption of aerosols

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Proceedings of Meetings on acoustics 2022年第1期46卷

作者： John Arthur Case Robert W. Smith 1Graduate Program in Acoustics The Pennsylvania State University University Park Pennsylvania 16802 USA jac7175@psu.edu 2Applied Research Laboratory The Pennsylvania State University State College PA 16801 USA rws100@arl.psu.edu

Atmospheric optical absorption, including the contribution from aerosols, is important in modeling propagation of laser beams and for climate research. Photoacoustic methods have been used in the past for this purpose, as they directly measure absorption, rather than the sum of absorption and scattering. Acoustic operating frequency determines the sensed aerosol size range. The design of a windowless double-Helmholtz photoacoustic aerosol sensing system, operating at an acoustic frequency near 150 Hz, with the capability to measure an optical absorption with a 1/e length of 1 Mm, will be presented. In this design, environmental noise limits the instrument sensitivity. To improve immunity to environmental noise with an open resonator, an aluminum acoustic enclosure was built around the system, with welded vacuum flanges for inputs and outputs. Inlet and outlet acoustic mufflers were designed to limit the in-band noise entering the measurement system. A modulated 10 W 1064 nm fiber laser was used as the excitation source, and a high-sensitivity microphone placed within the open-cell cavity was used to measure the internal photoacoustic pressure fluctuations. The system was modeled using various computational tools, including MATLAB, Simulink, and ANSYS, and then was constructed and tested. Lab measurement results will be presented.

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Optimal design and position of an embedded one-dimensional acoustic black hole 47

Optimal design and position of an embedded one-dimensional a...

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47th International Congress and Exposition on Noise Control Engineering: Impact of Noise Control Engineering, INTER-NOISE 2018

作者： McCormick, Cameron A. Shepherd, Micah R. Applied Research Laboratory Graduate Program in Acoustics Pennsylvania State University University ParkPA16802 United States

Structures whose thickness is tapered according to a power law exhibit the 'acoustic black hole' effect, and can be used for effective vibration reduction without adding mass. In this paper, we consider the problem of a one-dimensional acoustic black hole (ABH) with a free damping layer, embedded in a simply-supported beam which is excited by a harmonic force. The objective is to find the ABH design and position along the beam that simultaneously minimize the surface averaged square velocity response of the beam and the total mass of the beam. To determine the optimal design and position, a multi-objective evolutionary algorithm has been coupled with an automated meshing algorithm and commercial finite element software. The input variables are the taper profile of the ABH, the amount of damping, and the position of the ABH along the beam. Results of the optimization indicate that competition between design criteria exists, but only below a certain threshold. Optimization-based techniques like this can be applied to ABH design for more complex structures and can prove a valuable resource for noise control engineering. © INTER-NOISE 2018 - 47th International Congress and Exposition on Noise Control Engineering: Impact of Noise Control Engineering. All rights reserved.

关键词： Damping

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A comparison of algorithms for the vibroacoustic optimization of a beam: Gradient-based versus evolutionary

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Proceedings of Meetings on acoustics 2020年第1期42卷

作者： Cameron A. McCormick Micah R. Shepherd 1Applied Research Laboratory Graduate Program in Acoustics The Pennsylvania State University State College PA 16802 USA c.arthur.mccormick@*** mrs30@arl.psu.edu

Two common classes of optimization algorithm used in structural and/or multidisciplinary optimization are gradient-based algorithms and evolutionary algorithms. In the case of smooth, unimodal objective spaces, gradient-based algorithms are generally faster, requiring fewer iterations to reach a solution. Evolutionary algorithms, on the other hand, are more robust against objective spaces that are nonlinear, discontinuous, and/or multimodal. This talk will present an optimization of the thickness distribution of a cantilever beam, inspired by a similar study carried out by Berggren et al. [“Sound vibration damping optimization with application to the design of speakerphone casings,” 10th World Congress on Structural and Multidisciplinary Optimization, 2013]. The objective is to minimize the vibration response within a certain region of the beam at discrete frequencies, with constraints on total mass and static compliance. The objective space is expected to be nonlinear and potentially multimodal. A transfer matrix method is used to evaluate the objective function and constraints, and optimal solutions are found using both a gradient-based algorithm and an evolutionary algorithm. Qualitative and quantitative results will be presented in comparing the optimized distribution to that of Berggren et al. and in discussing the benefits and limitations of the two algorithms for vibroacoustic optimization.

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Coupling Rendering and Generative Adversarial Networks for Artificial SAS Image Generation

Coupling Rendering and Generative Adversarial Networks for A...

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OCEANS

作者： Albert Reed Isaac D. Gerg John D. McKay Daniel C. Brown David P. Williamsk Suren Jayasuriya School of Electrical Computer & Energy Engineering Arizona State University Tempe AZ USA School of Electrical Engineering and Computer Science Pennsylvania State University State College PA USA Applied Research Laboratory Pennsylvania State University State College PA USA Graduate Program in Acoustics Pennsylvania State University State College PA USA NATO STO Centre for Maritime Research & Experimentation La Spezia Italy School of Arts Media & Engineering Arizona State University Tempe AZ USA

There is a growing demand for large-scale Synthetic Aperture Sonar (SAS) datasets. This demand stems from data-driven applications such as Automatic Target Recognition (ATR) [1]-[3], segmentation [4] and oceanographic research of the seafloor, simulation for sensor prototype development and calibration [5], and even potential higher level tasks such as motion estimation [6] and micronavigation [7]. Unfortunately, the acquisition of SAS data is bottlenecked by the costly deployment of SAS imaging systems, and even when data acquisition is possible, the data is often skewed towards containing barren seafloor rather than objects of interest. This skew introduces a data imbalance problem wherein a dataset can have as much as a 1000-to-1 ratio of seafloor background to object-of-interest SAS image chips.

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Coupling rendering and generative adversarial networks for artificial SAS image generation

arXiv

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arXiv 2019年

作者： Reed, Albert Gerg, Isaac D. McKay, John D. Brown, Daniel C. Williams, David P. Jayasuriya, Suren School of Electrical Computer & Energy Engineering Arizona State University TempeAZ United States School of Arts Media & Engineering Arizona State University TempeAZ United States Applied Research Laboratory Pennsylvania State University State College PA United States Graduate Program in Acoustics Pennsylvania State University State College PA United States School of Electrical Engineering and Computer Science Pennsylvania State University State College PA United States NATO STO Centre for Maritime Research & Experimentation La Spezia Italy

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Benchmark problems for transcranial ultrasound simulation: Intercomparison of compressional wave models

arXiv

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arXiv 2022年

作者： Aubry, Jean-Francois Bates, Oscar Boehm, Christian Pauly, Kim Butts Christensen, Douglas Cueto, Carlos Gélat, Pierre Guasch, Lluis Jaros, Jiri Jing, Yun Jones, Rebecca Li, Ningrui Marty, Patrick Montanaro, Hazael Neufeld, Esra Pichardo, Samuel Pinton, Gianmarco Pulkkinen, Aki Stanziola, Antonio Thielscher, Axel Treeby, Bradley Van't Wout, Elwin Physics for Medicine Paris INSERM U1273 ESPCI Paris PSL University CNRS UMR 8063 France Department of Bioengineering Imperial College London Exhibition Road LondonSW7 2AZ United Kingdom Institute of Geophysics ETH Zürich Sonneggstrasse 5 Zürich8092 Switzerland Department of Radiology Stanford University StanfordCA United States Department of Biomedical Engineering Department of Electrical and Computer Engineering University of Utah United States Department of Surgical Biotechnology Division of Surgery and Interventional Science University College London LondonNW3 2PF United Kingdom Earth Science and Engineering Department Imperial College London London United Kingdom Centre of Excellence IT4Innovations Faculty of Information Technology Brno University of Technology Bozetechova 2 Brno612 00 Czech Republic Graduate Program in Acoustics The Pennsylvania State University University Park PA16802 United States Joint Department of Biomedical Engineering University of North Carolina at Chapel Hill North Carolina State University NC United States Department of Electrical Engineering Stanford University StanfordCA United States Zurich Switzerland Laboratory for Acoustics / Noise control Empa Swiss Federal Laboratories for Materials Science and Technology Dubendorf Switzerland Zurich Switzerland Radiology and Clinical Neurosciences Departments Cumming School of Medicine University of Calgary Canada Department of Applied Physics University of Eastern Finland Kuopio70211 Finland Department of Medical Physics and Biomedical Engineering University College London Gower Street LondonWC1E 6BT United Kingdom Technical University of Denmark Denmark Danish Research Center for Magnetic Resonance Copenhagen University Hospital Hvidovre Denmark Institute for Mathematical and Computational Engineering School of Engineering and Faculty of Mathematics Pontificia Universidad Catolica de Chile Santiago Chile

Computational models of acoustic wave propagation are frequently used in transcranial ultrasound therapy, for example, to calculate the intracranial pressure field or to calculate phase delays to correct for skull distortions. To allow intercomparison between the different modeling tools and techniques used by the community, an international working group was convened to formulate a set of numerical benchmarks. Here, these benchmarks are presented, along with intercomparison results. Nine different benchmarks of increasing geometric complexity are defined. These include a single-layer planar bone immersed in water, a multi-layer bone, and a whole skull. Two transducer configurations are considered (a focused bowl and a plane piston), giving a total of 18 permutations of the benchmarks. Eleven different modeling tools are used to compute the benchmark results. The models span a wide range of numerical techniques, including the finite-difference time-domain method, angular-spectrum method, pseudospectral method, boundary-element method, and spectral-element method. Good agreement is found between the models, particularly for the position, size, and magnitude of the acoustic focus within the skull. When comparing results for each model with every other model in a cross comparison, the median values for each benchmark for the difference in focal pressure and position are less than 10% and 1 mm, respectively. The benchmark definitions, model results, and intercomparison codes are freely available to facilitate further comparisons. Copyright © 2022, The Authors. All rights reserved.

关键词： Bone

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Global, regional, and national burden of diabetes from 1990 to 2021, with projections of prevalence to 2050: a systematic analysis for the Global Burden of Disease Study 2021

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The Lancet 2023年第10397期402卷 203-234页

作者： Ong, Kanyin Liane Stafford, Lauryn K. McLaughlin, Susan A. Boyko, Edward J. Vollset, Stein Emil Smith, Amanda E. Dalton, Bronte E. Duprey, Joe Cruz, Jessica A. Hagins, Hailey Lindstedt, Paulina A. Aali, Amirali Abate, Yohannes Habtegiorgis Abate, Melsew Dagne Abbasian, Mohammadreza Abbasi-Kangevari, Zeinab Abbasi-Kangevari, Mohsen ElHafeez, Samar Abd Abd-Rabu, Rami Abdulah, Deldar Morad Abdullah, Abu Yousuf Md Abedi, Vida Abidi, Hassan Aboagye, Richard Gyan Abolhassani, Hassan Abu-Gharbieh, Eman Abu-Zaid, Ahmed Adane, Tigist Demssew Adane, Denberu Eshetie Addo, Isaac Yeboah Adegboye, Oyelola A. Adekanmbi, Victor Adepoju, Abiola Victor Adnani, Qorinah Estiningtyas Sakilah Afolabi, Rotimi Felix Agarwal, Gina Aghdam, Zahra Babaei Agudelo-Botero, Marcela Arriagada, Constanza Elizabeth Aguilera Agyemang-Duah, Williams Ahinkorah, Bright Opoku Ahmad, Danish Ahmad, Rizwan Ahmad, Sajjad Ahmad, Aqeel Ahmadi, Ali Ahmadi, Keivan Ahmed, Ali Ahmed, Luai A. Ahmed, Syed Anees Ajami, Marjan Akinyemi, Rufus Olusola Al Hamad, Hanadi Al Hasan, Syed Mahfuz AL-Ahdal, Tareq Mohammed Ali Alalwan, Tariq A. Al-Aly, Ziyad AlBataineh, Mohammad T. Alcalde-Rabanal, Jacqueline Elizabeth Alemi, Sharifullah Ali, Hassam Alinia, Tahereh Aljunid, Syed Mohamed Almustanyir, Sami Al-Raddadi, Rajaa M. Alvis-Guzman, Nelson Amare, Firehiwot Ameyaw, Edward Kwabena Amiri, Sohrab Amusa, Ganiyu Adeniyi Andrei, Catalina Liliana Anjana, Ranjit Mohan Ansar, Adnan Ansari, Golnoosh Ansari-Moghaddam, Alireza Anyasodor, Anayochukwu Edward Arabloo, Jalal Aravkin, Aleksandr Y. Areda, Demelash Arifin, Hidayat Arkew, Mesay Armocida, Benedetta Arnlov, Johan Artamonov, Anton A. Arulappan, Judie Aruleba, Raphael Taiwo Arumugam, Ashokan Aryan, Zahra Asemu, Mulu Tiruneh Asghari-Jafarabadi, Mohammad Askari, Elaheh Asmelash, Daniel Astell-Burt, Thomas Athar, Mohammad Athari, Seyyed Shamsadin Atout, Maha Moh'd Wahbi Avila-Burgos, Leticia Awaisu, Ahmed Azadnajafabad, Sina Darshan, B.B. Babamohamadi, Hassan Badar, Muhammad Badawi, Alaa Badiye, Ashish D. Baghcheghi, Nayereh Baghe Institute for Health Metrics and Evaluation School of Medicine General Medicine Service Department of Veterans Affairs Seattle WA United States Department of Health Metrics Sciences School of Medicine Faculty of Medicine France Department of Clinical Governance and Quality Improvement Aleta Wondo Hospital Aleta Wondo Ethiopia Department of Nursing Woldia University Woldia Ethiopia Department of Nursing Department of Orthopedic Surgery Orthopaedic Surgery Social Determinants of Health Research Center Non-communicable Diseases Research Center Epidemiology Department Evidence-Based Practice Center Community and Maternity Nursing Unit University of Duhok Duhok Iraq School of Planning Faculty of Environment Department of Public Health Sciences Penn State College of Medicine Pennsylvania State University Hershey PA United States Biocomplexity Institute Virginia Tech Blacksburg VA United States College of Medicine Department of Public Health Laboratory Technology Sciences Department Department of Family and Community Health University of Health and Allied Sciences Ho Ghana Research Center for Immunodeficiencies Department of Biosciences and Nutrition Karolinska University Hospital Huddinge Sweden Clinical Sciences Department Department of Surgery Department of Surgery Department of Obstetrics & Gynecology College of Graduate Health Sciences University of Tennessee Memphis TN United States Department of Obstetrics & Gynecology Department of Clinical and Psychosocial Epidemiology Department of Anesthesia and Critical Care Centre for Social Research in Health Quality and Systems Performance Unit Cancer Institute NSW Sydney NSW Australia Department of Public Health and Tropical Medicine HIV and Infectious Diseases Department Jhpiego Abuja Nigeria Adolescent Research and Care Department Adolescent Friendly Research Initiative and Care Ado Ekiti Nigeria Department of Epidemiology Department of Epidemiology and Medical Statistics Department of Family Medicine McMaster University

Background: Diabetes is one of the leading causes of death and disability worldwide, and affects people regardless of country, age group, or sex. Using the most recent evidentiary and analytical framework from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), we produced location-specific, age-specific, and sex-specific estimates of diabetes prevalence and burden from 1990 to 2021, the proportion of type 1 and type 2 diabetes in 2021, the proportion of the type 2 diabetes burden attributable to selected risk factors, and projections of diabetes prevalence through 2050. Methods: Estimates of diabetes prevalence and burden were computed in 204 countries and territories, across 25 age groups, for males and females separately and combined;these estimates comprised lost years of healthy life, measured in disability-adjusted life-years (DALYs;defined as the sum of years of life lost [YLLs] and years lived with disability [YLDs]). We used the Cause of Death Ensemble model (CODEm) approach to estimate deaths due to diabetes, incorporating 25 666 location-years of data from vital registration and verbal autopsy reports in separate total (including both type 1 and type 2 diabetes) and type-specific models. Other forms of diabetes, including gestational and monogenic diabetes, were not explicitly modelled. Total and type 1 diabetes prevalence was estimated by use of a Bayesian meta-regression modelling tool, DisMod-MR 2.1, to analyse 1527 location-years of data from the scientific literature, survey microdata, and insurance claims;type 2 diabetes estimates were computed by subtracting type 1 diabetes from total estimates. Mortality and prevalence estimates, along with standard life expectancy and disability weights, were used to calculate YLLs, YLDs, and DALYs. When appropriate, we extrapolated estimates to a hypothetical population with a standardised age structure to allow comparison in populations with different age structures. We used the comparative r

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Evaluation of bolt torque levels using nonlinear wave modulation spectroscopy

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AIP Conference Proceedings 2019年第1期2102卷

作者： Carter L. Neblett Manton J. Guers Dean E. Capone 1Graduate Program in Acoustics The Pennsylvania State University University Park PA 16802 USA 2Applied Research Laboratory PO Box 30 The Pennsylvania State University University Park PA 16804 USA

Nondestructive evaluation techniques have been used to evaluate the integrity of bolted joints in structures. One such method is nonlinear wave modulation spectroscopy (NWMS), which examines the sideband generation in the presence of dual inputs as a result of nonlinearity present in the system. This work uses NWMS on an aluminum T-joint structure to evaluate the torque levels of the bolts. In addition, this work compares excitation with two shakers to excitation with a single shaker and an impact hammer, in which the hammer excites several low frequency modes. The results show that the damage indicator based on the sidebands is highly dependent on damage and sensor location, and that the damage indicator is most sensitive over a specific range of torque levels.

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Summary of "Biomedical acoustics and Physical acoustics: Shock Waves and Ultrasound for Calculus Fragmentation"

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Proceedings of meetings on acoustics. Acoustical Society of America 2018年第1期35卷 002001页

作者： Julianna C Simon Michael R Bailey Graduate Program in Acoustics Pennsylvania State University Penn State 201E Applied Sciences Building University Park Pennsylvania 16802. Center for Industrial and Medical Ultrasound Applied Physics Laboratory University of Washington 1013 NE 40th St. Seattle Washington 98105.

This paper summarizes the special session, "Shock Waves and Ultrasound for Calculus Fragmentation," that took place during the 176th Meeting of the Acoustical Society of America and 2018 acoustics Week in Canada. The sessions were cosponsored by the Biomedical acoustics and Physical acoustics Technical Committees and consisted of ten talks by industry and academic researchers from institutions in the United states, France, and the Russian Federation. The sessions described basic and applied acoustic research to manage urinary stones.

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