bluuebunny/crossref_metadata_2025 huggingface dataset:
Graduate studies in acoustics at the University of Notre Dame
Authors: Corke Thomas , Jasinski Christopher
Published: June 2017

The University of Notre Dame department of Aerospace and Mechanical Engineering is conducting cutting edge research in aeroacoustics, structural vibration, and wind turbine noise. Expanding facilities are housed at two buildings of the Hessert Laboratory for Aerospace Engineering and include two 25 kW wind turbines, a Mach 0.6 wind tunnel, and an anechoic wind tunnel. Several faculty members conduct research related to acoustics and multiple graduate level courses are offered in general acoustics and aeroacoustics. This poster presentation will give an overview of the current research activities, laboratory facilities, and graduate students and faculty involved at Notre Dame’s Hessert Laboratory for Aerospace Engineering.
Graduate programs in Hearing and Speech Sciences at Vanderbilt University
Authors: Stecker G. Christopher
Published: June 2017

The Department of Hearing and Speech Sciences at Vanderbilt University is home to several graduate programs in the areas of Psychological and Physiological Acoustics and Speech Communication. Programs include the PhD in Audiology, Speech-Language Pathology, and Hearing or Speech Science, Doctor of Audiology (Au.D.), and Master’s programs in Speech-Language Pathology and Education of the Deaf. The department is closely affiliated with Vanderbilt University’s Graduate Program in Neurobiology. Several unique aspects of the research and training environment in the department provide exceptional opportunities for students interested in studying the basic science as well as clinical-translational aspects of auditory function and speech communication in complex environments. These include anechoic and reverberation chambers capable of multichannel presentation, the Dan Maddox Hearing Aid Laboratory, and close connections to active Audiology, Speech-Pathology, Voice, and Otolaryngology clinics. Students interested in the neuroscience of communication utilize laboratories for auditory and multisensory neurophysiology and neuroanatomy, human electrophysiology and neuroimaging housed within the department and at the neighboring Vanderbilt University Institute for Imaging Science. Finally, department faculty and students engage in numerous engineering and industrial collaborations, which benefit from our home within Vanderbilt University and setting in Music City, Nashville Tennessee.
Graduate Education in Acoustics at The Catholic University of America
Authors: Vignola Joseph F. , Turo Diego , Guan Shane , Ryan Teresa J.
Published: June 2017

The Catholic University of America (CUA) has a graduate program with a long history in acoustics dating back to the early 1930s. The acoustics program moved to the School of Engineering in the 1960s when there were strong needs in underwater acoustic studies to meet U.S. Naval applications. The end of the Cold War was concurrent with a decline in the CUA’s acoustics education that persisted into the 1990s. However, renewed interests in acoustical engineering, acoustic metamaterial, and environmental acoustic research has revived the acoustics research and education programs at the CUA in recent years. Currently, a variety of graduate level acoustic courses are being offered in the CUA’s Mechanical Engineering Department. Students can pursue a master’s degree or Ph.D. degree with research in acoustics or vibrations. The courses in the program include a two-course sequence in fundamentals in acoustics, and more focused courses in ocean acoustics, atmospheric acoustics, acoustic metrology, marine bioacoustics, nonlinear vibration, acoustic imaging, and acoustic metamaterials. In addition, CUA offers masters and Ph.D. programs to students who are interested in the field of acoustic research.
Graduate Acoustics at the University of New Hampshire
Authors: Lyons Anthony P. , Miksis-Olds Jennifer L. , Weber Thomas C.
Published: June 2017

The University of New Hampshire (UNH) offers several opportunities for graduate students interested in studying acoustics and its application. Faculty mentors who are expert in acoustic methods and technologies reside in a range of programs and departments that are largely focused on the use of acoustics in the marine environment, including biological science, earth science, mechanical engineering, natural resources and earth systems, ocean engineering, and oceanography. UNH faculty mentors who specialize in acoustics are active in the Animal Bioacoustics, Acoustical Oceanography, and Underwater Acoustics technical committees. Recent studies by faculty and students focusing on fundamental acoustic problems, such as those that would cause a graduate student to be a regular attendee of meetings of the Acoustical Society of America, have come largely from mechanical engineering, ocean engineering, and the newly formed School of Marine Sciences and Ocean Engineering. Graduate students in these programs of study have the opportunity for formal classroom training in the fundamentals of acoustics, vibrations, and advanced topics in ocean acoustics as they pursue their graduate training.
Acoustics research and graduate studies within the College of Engineering at the University of Nebraska—Lincoln
Authors: Wang Lily M. , Ryherd Erica E. , Turner Joseph A. , Zhu Jinying
Published: June 2017

The University of Nebraska—Lincoln (UNL) offers opportunities to study and conduct research in acoustics within a number of our graduate engineering degree programs, including (1) Architectural Engineering (AE) within the Durham School of Architectural Engineering and Construction, (2) Civil Engineering (CIVE) and (3) Mechanical and Materials Engineering (MME). Dr. Lily Wang and Dr. Erica Ryherd (faculty in the Durham School, based at UNL’s Scott Campus in Omaha) are active in architectural acoustics and noise. More information on the ‘Nebraska Acoustics Group’ within the Durham School may be found online at http://nebraskaacousticsgroup.org/. Dr. Jinying Zhu (faculty in CIVE, also based on UNL’s Scott Campus in Omaha) focuses in structural acoustics, using ultrasonic waves for non-destructive evaluation of concrete structures and material. Dr. Joseph Turner (faculty in MME, based at UNL’s City Campus in Lincoln) studies ultrasound propagation through complex media for quantitative characterization of materials/microstructure (http://quisp.unl.edu). UNL additionally hosts an active student chapter of the Acoustical Society of America, the first to be founded in 2004. The poster will describe the graduate-level acoustics courses and lab facilities at UNL, as well as the research interests and achievements of our faculty, graduates, and students.
Acoustics-related graduate programs at the University of Minnesota
Authors: Whiteford Kelly L. , Nelson Peggy B. , Lim Hubert H. , Bee Mark , Oxenham Andrew J.
Published: June 2017

The University of Minnesota offers a wide variety of graduate programs related to acoustics, primarily in the areas of Speech Communication, Psychological and Physiological Acoustics, and Animal Bioacoustics. Degree programs include Psychology (Ph.D.), Speech-Language-Hearing Sciences (M.A., Au.D., and Ph.D.), Biomedical Engineering (M.S. and Ph.D.), Ecology, Evolution, and Behavior (Ph.D.), and Neuroscience (Ph.D.). Faculty across departments have a shared interest in understanding how the ear and brain work together to process sound and in developing new technologies and approaches for improving hearing disorders. The university offers a number of resources for pursuing research related to these topics. The Center for Applied and Translational Sensory Science (CATSS) provides opportunities for utilizing interdisciplinary collaborations to better understand sensory-related impairments, including hearing loss and low vision. Within CATSS is the Multi-Sensory Perception Lab, which houses shared equipment, including eye trackers, and electroencephalography. The Center for Magnetic Resonance Research houses several ultrahigh field magnets, while the Center for Neural Engineering and affiliated faculty labs also house multiple neuromodulation and neurorecording devices to interact with and monitor neural activity in humans and animals. Students and faculty gather monthly for the Acoustic Communication Seminar, where labs alternate presenting their research findings and identify new collaborative research directions.
Acoustics and ocean engineering at the University of Rhode Island
Authors: Van Uffelen Lora J. , Potty Gopu R. , Miller James H
Published: June 2017

Acoustics is one of the primary areas of emphasis in the Ocean Engineering Department at the University of Rhode Island, one of the oldest Ocean Engineering programs in the United States. The program offers Bachelors, Masters (thesis and non-thesis options), and Ph.D. degrees in Ocean Engineering. These programs are based at Narragansett Bay, providing access to a living laboratory for student learning. Some key facilities of the program are the 100-foot-long wave tank, acoustics tank, and R/V Endeavor, a UNOLS oceanographic research vessel operated by the University of Rhode Island. At the graduate level, students are actively involved in research focused in areas such as acoustical oceanography, propagation modeling, geoacoustic inversion, marine mammal acoustics, ocean acoustic instrumentation, and transducers. An overview of classroom learning and ongoing research will be provided, along with information regarding the requirements of entry into the program.
Graduate Studies in Acoustics at Northwestern University
Authors: Cole Jennifer , Goldrick Matthew , Bradlow Ann
Published: June 2017

Northwestern University has a vibrant and highly interdisciplinary community of acousticians. Of the 13 ASA technical areas, 3 have strong representation at Northwestern: Speech Communication, Psychological and Physiological Acoustics, and Musical Acoustics. Sound-related work is conducted across a wide range of departments including Linguistics (in the Weinberg College of Arts and Sciences), Communication Sciences & Disorders, and Radio/Television/Film (both in the School of Communication), Electrical Engineering & Computer Science (in the McCormick School of Engineering), Music Theory & Cognition (in the Bienen School of Music), and Otolaryngology (in the Feinberg School of Medicine). In addition, The Knowles Hearing Center involves researchers and labs across the university dedicated to the prevention, diagnosis, and treatment of hearing disorders. Specific acoustics research topics across the university range from speech perception and production across the lifespan and across languages, dialect and socio-indexical properties of speech, sound design, machine perception of music and audio, musical communication, the impact of long-term musical experience on auditory encoding and representation, auditory perceptual learning, and the cellular, molecular, and genetic bases of hearing function. We invite you to visit our poster to learn more about the “sonic boom” at Northwestern University!
Graduate studies in Acoustics and Noise Control in the School of Mechanical Engineering at Purdue University
Authors: Davies Patricia , Bolton J. S. , Li Kai M.
Published: June 2017

The acoustics community at Purdue University will be described with special emphasis on the graduate program in Mechanical Engineering. Around 30 Purdue faculty study aspects of acoustics and closely related disciplines and so there are many classes to choose from as graduate students structure their plans of study to complement their research activities and to broaden their understanding of acoustics. In Mechanical Engineering, the primary emphasis is on understanding noise generation, noise propagation, and the impact of noise on people, as well as development of noise control strategies, experimental techniques, and noise impact prediction tools. The noise control research is conducted at the Ray W. Herrick Laboratories, which houses several large acoustics chambers that are designed to facilitate testing of a wide array mechanical systems, reflecting the Laboratories’ long history of industry-relevant research. Complementing the noise control research, Purdue has vibrations, dynamics, and electromechanical systems research programs and is home to a collaborative group of engineering and psychology professors who study human perception and its integration into engineering design. There are also very strong ties between ME acoustics faculty and faculty in Biomedical Engineering and Speech Language and Hearing Sciences.
Six decades of inspiration: Thomas D. Rossing, internationally renowned musical acoustician, writer, educator, and friend
Authors: Campbell D. Murray
Published: June 2017

Tom Rossing occupies a very special place in the international community of researchers in musical acoustics. Generations of undergraduate and postgraduate students have been directed to The Physics of Musical Instruments by Fletcher and Rossing as the most helpful and authoritative textbook in this interdisciplinary field. Specialists in the study of percussion and stringed instruments have enjoyed and profited from the textbooks which he has written and edited on these topics, and from the many research papers which he has published. He has traveled widely, researching and teaching not only in the United States but also in Australia, England, France, Germany, the Netherlands, Scotland, South Korea, and Sweden. He has been a stalwart supporter of the series of International Symposia in Musical Acoustics, and has made an outstanding contribution to the promotion of education in acoustics. Musical acousticians worldwide owe Tom a great debt of gratitude for his collaboration, inspiration, and friendship.
“Mode studies in musical instruments,” a journey with Tom
Authors: Hansen Uwe J.
Published: June 2017

For me, that journey began when Tom agreed to have me work with him in 1984. While Tom was busy at the Minneapolis ASA meeting, I learned about holographic interferometry at Dick Peterson's laboratory at Bethel College, while mode mapping a guitar, for which Tom had designed a support rack which isolated the front and back plates, enabling us to record their principle resonances. Immediately following that experience, we went on a whirlwind tour, meeting with some of the “Greats” in musical acoustics. Starting with Carleen Hutchins, we then met with Norman Pickering in Southampton, did some modal analysis guitar studies at the Steinway laboratories with William Y. Strong, and later visited with Gaby Weinreich. We concluded the tour with a visit to Gila Eba,'s guitar building studio. In the course of studying two-tone Chinese bells, we used judicious mirror placements to observe the bell modes in three dimensions. Eventually, the wet plates were replaced by Karl Stetson's computer based device, enabling us to study many instruments, such as Caribbean Steel-Pans much more efficiently. All these experiences led to world-wide opportunities, and a life-long, cherished friendship.
Machinery noise in a commercial building
Authors: Beristain Sergio
Published: June 2017

A commercial building was designed for installation of offices, open public commercial sites, and exhibits, with multiple fixed small and large stores and wide corridors, to include small temporal exhibits or small booths for commercial or information purposes. Noise generated from all of the building services machinery, such as temperature control and hygiene systems, was an issue, so ventilating systems, water pumps, garbage disposal, and the like had to be installed in a convenient way in order to avoid intruding noise, either to workers or customers. The building is a large solid concrete structure where every effort had to be made in order to properly insulate all the machinery producing noise and vibrations in order to provide all the necessary services, and at the same time, adequate acoustics comfort.
Rolling noise modeling in buildings
Authors: Chevillotte Fabien , Bécot François-Xavier , Jaouen Luc
Published: June 2017

New buildings in urban areas are divided in commercial and living surfaces. This usage has revealed critical disturbances due to the noise of the trolleys delivering at time where the buildings are mostly occupied, e.g., early times in the morning. Rolling trolleys indeed generate low frequency vibrations (below 100 Hz) which propagate easily in the entire building structure and in upper storeys. This work presents an original model for rolling noise in buildings. The developed model is able to account for the ground surface roughness as well as the rolling wheel asperity profile. It also enables to consider the mechanical impedance of the ground including some possible flooring noise treatment. It is shown that the model is able to correctly reproduce the measured level of vibrations and measured noise levels. It is also proved to accurately predict the sensitivity to different types of rolling noise and floorings having various properties, based on a single layer or a multi-layer construction.
The inlets and outlets of ducted silencer selection
Authors: Kaytt Thomas , DeLoach Alana
Published: June 2017

The passive in-duct attenuator is an established, but often misused, staple of the modern HVAC design toolbox. All too often, a quick silencer selection without thought to the system at large can cause havoc with a noise sensitive application. How often have you seen a “typical” silencer scheduled throughout a project without regard to the specifics of the rooms being treated? This paper will review various types of silencers as well as location & selection methods to balance noise control needs against airflowcapacities, air quality, and space restrictions. Case studies will be presented to illustrate some of the classic silencer design and installation errors.
Incorporating measurement standards in an advanced acoustics laboratory course
Authors: Gee Kent L.
Published: June 2017

In an advanced acoustics laboratory course at Brigham Young University, students are introduced to ANSI measurement standards in the context of sound power. They are introduced to the anatomy of a typical acoustics standard and then plan and carry out sound power measurements of an electric leaf blower using both reverberation chamber and sound intensity methods. The students are required to write a technical memorandum describing (a) the blower’s radiated sound power levels over an appropriate frequency range, as obtained with the two methods; (b) setup documentation and deviations from the standards’ recommended practices; and (c) how any deviations might have contributed to discrepancies between the sound power levels obtained with the two methods. In this talk, a description of the experience from the faculty and student perspectives is given, along with plans for future improvements.
German DIN 18041 Acoustic Quality in Rooms
Authors: Nocke Christian
Published: June 2017

DIN 18041 was first published in 1968 and at that time summarized a lot of knowledge in the field of room acoustics on the design of everyday life rooms such as class rooms, lecture halls, conference rooms, etc. DIN 18041 was first revised in 2004; a second revision was undertaken from October 2013 to mid 2015 to commit the room acoustic requirements for the implementation of the inclusion in the field of hearing and to take into account trends in the modern architecture. In addition to these technical and social aspects DIN 18041 of 2016 with the new title “Acoustic quality in rooms — requirements, recommendations and instructions for planning” gives clarifications and additions as well as deletions compared to the edition of 2004. These changes are presented and discussed. The revision of DIN 18041 provides clear and unambiguous guidelines described as requirements and recommendations for everyday rooms where the mutual listening and understanding but also finding of quietness is of significant importance. The use of standards in education for education facilities will be discussed.
Incorporating standards into an instrumentation class
Authors: Feth Lawrence L.
Published: June 2017

First-year AuD students at Ohio State take Acoustics and Instrumentation in their first semester in the program. The course is offered simultaneously with courses in psychoacoustics and anatomy and physiology of the auditory system, as well as the first course in assessment covering behavioral testing. It is essentially a prerequisite for the two-course sequence on hearing aids, and later assessment courses covering middle ear measurements and ABR, as well as courses on cochlear implants and hearing conservation. Students enrolled in the course generally do not have a strong background in math and physics, but they are competent in algebra and trigonometry. One goal of the course is to develop a conceptual understanding of the basic acoustical and electronics principles underlying electroacoustic measurements. included with in those goals is the introduction to electroacoustic standards and to the role they play in the practice of audiology. To that end, the on-line instruction on standards offered by ANSI and the content of a recent two volume issue of Seminars in Hearing are incorporated into the “conventional” materials on acoustics and electronics. One unique feature of the course is the use of essay exams to test underlying concepts usually taught by “plug-and-chug” drills.
Uncertainty of ANSI/ASA S12.42 Hearing Protection Device Impulsive Measurements
Authors: Fackler Cameron J. , Berger Elliott H. , Stergar Michael E.
Published: June 2017

ANSI/ASA S12.42 was extended in 2010 to include methods for measuring the performance of hearing protection devices (HPDs) in impulsive noise conditions. The standard specifies the instrumentation, methods, and data analysis required to measure impulse peak insertion loss (IPIL). IPIL is defined as the amount by which an HPD reduces the effective peak level of an impulsive sound. To characterize HPDs whose attenuation may be level-dependent, IPIL is measured at several impulse peak sound pressure levels, typically in the range of 130-170 dB. Factors contributing to the uncertainty of IPIL measurements include repeatability in the generation of test impulses, variability of the HPD samples under test and their repeated fitting to the test fixture, and spectral properties of the impulse source and the HPD’s attenuation. To help inform future revisions to the S12.42 standard, we quantify IPIL measurement uncertainty for a variety of HPDs tested with two different impulsive sound sources. End users of HPDs should be educated about the uncertainty inherent in IPIL assessments of HPD performance.
Methodology for designing aircraft having optimal sound signatures
Authors: Sahai Abhishek K. , van Hemelen Tom , Simons Dick G.
Published: June 2017

This paper presents a methodology with which aircraft designs can be modified such that they produce optimal sound signatures on the ground. With optimal sound it is implied in this case sounds that are perceived as less annoying by residents living near airport vicinities. A novel design and assessment chain has been developed which combines the aircraft design process with an auralization and sound quality assessment capability. It is demonstrated how different commercial aircraft can be designed, their sounds auralized at representative locations in airport vicinities and subsequently assessed for sound quality. As sound quality is closely related to the perceived annoyance, it is expected that designs with improved sound quality would also be perceived as less annoying. By providing a feedback to the design optimizer in terms of one of the sound quality metrics or a suitable combination thereof, the designs of aircraft can be altered to produce potentially less annoying sounds. The paper will focus on three current aircraft and will demonstrate the application of the novel design chain to auralize and alter their sounds toward improved sound quality. The presented methodology can also be extended to unconventional aircraft configurations and propulsion concepts, for optimizing future aircraft sounds.
Practical consideration for measuring airborne ultrasound measurement
Authors: Harwell Isaac , Bommer Arno S.
Published: June 2017

When attempting to make meaningful measurements, airborne ultrasound in the 20 kHz to 100 kHz frequency range presents several significant challenges. These include source and sensor directivity, low signal-to-noise ratios, the inaudible nature of such sounds, and the lack of widespread literature on the subject. For each of these challenges, the practical impacts versus conventional acoustic measurements are identified and discussed. Solutions and suggestions are presented to allow reliable and repeatable measurements when presented with these challenges, including critical information to have prior to measurement, an assortment of techniques which may be employed when performing these measurements, and a brief overview of useful post-processing techniques. The concepts presented in this paper are illustrated using ultrasound measurements made in a vivarium.
Elastic energy harvesting: Materials and applications
Authors: Gladden Josh R.
Published: June 2017

As societies wean themselves off fossil fuel based energy sources, an “all of the above” approach will be required to satisfy expanding energy needs. This necessitates a renewed creativity from the scientific and engineering communities. Various ambient energy sources hold potential to supply power in particular applications. Solar and wind are of course well known examples, but vibrational, or elastic, energy should not be overlooked. A key component in harnessing any ambient energy source is the transduction mechanism to convert the energy from its original form into electrical. In this talk, I will explore available energy densities in a number of common scenarios, novel energy conversion materials, and discuss some niche applications.
Challenges in practical operational testing of a nuclear powered thermoacoustic sensor
Authors: Smith James A. , Garrett Steven L. , Bascom Andrew , Heidrich Brenden , Heibel Michael
Published: June 2017

The world’s first nuclear powered, wireless power and temperature sensor was demonstrated in Penn State’s Breazeale Nuclear Reactor during the last week of September 2015. The sensor consisted of a thermoacoustic heat engine powered by nuclear fission designed to acoustically telemeter temperature and neutron flux information. The acoustic frequency of operation and the amplitude of the acoustic signal were proportional to the temperature and the reactor power respectively. The proof-of-concept tests were conducted in the research reactor twice daily over five days. Sensor performance was as expected with the exception that the amplitude of the acoustic signal diminished after each test. In this paper we will present our “wet sock” theory that a seal weld isolating the thermal insulation from the reactor coolant at the hot end of the thermoacoustic sensor failed early in the testing. This allowed water to be drawn in each time the thermoacoustic sensor cooled down reducing the efficiency of the insulation and therefore the sensor output. Thermometric data will be presented that supports our hypothesis. The result of this testing validates the resilience of the thermoacoustic sensor to adverse conditions present in the core of a nuclear reactor even when degraded. Lessons learned in the initial testing will be carried forward to the planned Advanced Test Reactor experiments in 2017.
Acoustic measurement infrastructure to enable the enhancement of nuclear reactor efficiency and safety
Authors: agarwal Vivek , Smith James A.
Published: June 2017

Nuclear research reactors are used to test efficiency and safety of new technology, such as material or fuel samples under prototypic commercial conditions, operation of reactor prototypes, safety studies, assessment of neutron parameters, etc. Many experiments performed in research reactors require in-situ measurements to monitor the progress and performance of conducted tests. The core of any nuclear reactor presents a particularly harsh environment for sensors and instrumentations. The reactor core also imposes challenging constraints on signal transmission from inside the reactor core to outside of the reactor vessel. In this paper, an acoustic measurement infrastructure (AMI) installed at the Advanced Test Reactor (ATR), located at Idaho National Laboratory, is presented. The AMI consists of ATR in-pile structural components, coolant, acoustic receivers, primary coolant pumps, a data-acquisition system, and signal processing algorithms. Intrinsic and cyclic acoustic signals generated by the operation of the primary coolant pumps are collected using acoustic receivers and processed. The characteristics of the intrinsic signal can indicate the process state of the ATR during operation (i.e., real-time measurement). The innovation of AMI can be extended to collect information on other phenomena, such as fuel motion, individual fuel rod vibration, loose parts, thermal expansion, and flow blockage, that occur inside an operating nuclear reactor.
Optimization of acoustic absorption by green walls made of foliage and substrate
Authors: Attal Emmanuel , Côté Nicolas , Shimizu Takafumi , Dubus Bertrand
Published: June 2017

Green walls may absorb sound and contribute to noise reduction in urban areas. Recent experiments demonstrate that a foliage layer placed above a substrate layer may lead to a significant increase of acoustic absorption coefficient in a broad frequency range. However, the physical origin of this improvement remains unclear. In this work, measurements are carried out in an impedance tube on foliage, substrate, and foliage/substrate samples using the three-microphone two-load method. Acoustic absorption coefficient and surface specific impedance are measured in rigid backing condition between 100 and 1000 Hz. Effective speed of sound and characteristic impedance are also experimentally determined for foliage and substrate. For foliage/substrate samples, a good agreement is obtained between measured acoustic absorption coefficients and calculated ones using the effective properties of foliage and substrate layer and matrix manipulations. Analysis of results reveals that absorption coefficient spectrum is mainly explained by the thickness resonances of the sample and by the impedance matching between air and substrate provided by the foliage.
Examining auditory selective attention in reverberant environments
Authors: Oberem Josefa , Seibold Julia , Koch Iring , Fels Janina
Published: June 2017

Using a well-established binaural-listening paradigm, the ability to intentionally switch auditory selective attention was examined under anechoic, low reverberation (0.8 s) and high reverberation (1.75 s) conditions. Twenty-four young, normal-hearing subjects were tested in a within-subject design to analyze influences of the reverberation times. Spoken word pairs by two speakers were presented simultaneously to subjects from two of eight azimuth positions. The stimuli were word pairs that consisted of a single number word (i.e., 1 to 9) followed by either the German direction “UP” or “DOWN.” Guided by a visual cue prior to auditory stimulus onset indicating the position of the target speaker, subjects were asked to identify whether the target number was numerically smaller or greater than five and to categorize the direction of the second word. Switch costs (i.e., reaction time differences between a position switch of the target relative to a position repetition) were larger for the high reverberation condition. Furthermore, the error rates were highly dependent on reverberation times and interacted with the congruency effect (i.e., stimuli spoken by target and distractor may evoke the same answer (congruent) or different answers (incongruent)), indicating larger congruency effects in higher reverberation.
Measuring auditory spatial perception in realistic environments
Authors: Best Virginia , Buchholz Jorg M. , Weller Tobias
Published: June 2017

While much is known about how well listeners can locate single sound sources under ideal conditions, it remains unclear how this ability relates to the more complex task of spatially analyzing realistic acoustic environments. There are many challenges in measuring spatial perception in realistic environments, including generating simulations that offer a level of experimental control, dealing with the presence of energetic and informational masking, and designing meaningful behavioral tasks. In this work we explored a new method to measure spatial perception in one realistic environment. A large reverberant room was simulated using a loudspeaker array in an anechoic chamber. Within this room, 96 different “scenes” were generated, comprising 1-6 concurrent talkers seated at different tables. Listeners were presented with 45-sec samples of each scene, and were required to count, locate, and identify the gender of all talkers, using a touchscreen interface. Young listeners with normal hearing were able to reliably analyze scenes with up to four simultaneous talkers, while older listeners with hearing loss demonstrated errors even with two talkers at a time. Localization accuracy for detected talkers, as measured by this approach, was sensitive both to the complexity of the scene and to the listener’s degree of hearing loss.
Modeling speech localization, identification, and word recognition in a multi-talker setting
Authors: Josupeit Angela , Luberadzka Joanna , Hohmann Volker
Published: June 2017

In many everyday situations, listeners are confronted with complex acoustic scenes. Despite the complexity of these scenes, they are able to follow and understand one particular talker. This contribution presents auditory models that aim to solve speech-related tasks in multi-talker settings. The main characteristics of the models are: (1) restriction to salient auditory features (“glimpses”); (2) usage of periodicity, periodic energy, and binaural features; and (3) template-based classification methods using clean speech models. Further classification approaches using state-space models will be discussed. The model performance is evaluated on the basis of human psychoacoustic data [e.g., Brungart and Simpson, Perception & Psychophysics, 2007, 69(1), 79-91; Schoenmaker and van de Par, Physiology, Psychoacoustics and Cognition in Normal and Impaired Hearing, 2016, 73-81]. The model results were mostly found to be similar to the subject results. This suggests that sparse glimpses of periodicity-related monaural and binaural auditory features provide sufficient information about a complex auditory scene involving multiple talkers. Furthermore, it can be concluded that the usage of clean speech models is sufficient to decode speech information from the glimpses derived from a complex scene, i.e., computationally complex models of sound source superposition are not required for decoding a speech stream.
Annoyance due to railway noise and vibrations: A comparison of two methods of collecting annoyance scores
Authors: Maigrot Philéas , Marquis-Favre Catherine , Parizet Etienne
Published: June 2017

An experiment has been conducted in order to determine if the method of collecting partial and overall annoyance scores—during separated sessions or during the same session—has an influence on the participants’ answers. The experiment used controlled noise and vibration stimuli corresponding to a train pass-by, recorded inside a house in the vicinity of a railway track. 32 participants attended 4 sessions A, B, C, and D during each of which they were presented with 16 combinations of noise and vibrations. They had to evaluate partial annoyance due to noise in the presence of vibration (session A), partial annoyance due to vibrations in the presence of noise (session B) or overall annoyance (session C). Lastly, they were asked to rate partial and overall annoyances in a same session (session D). Results show that partial and overall annoyance scores, simultaneously collected during session D, were quite similar to the ones respectively collected during dedicated sessions. Furthermore, this method is convenient as a reduced number of stimuli is presented to each participant.
Annoyance response and improvement of Zwicker's psychoacoustic annoyance model aiming at tonal noises
Authors: Di Guoqing
Published: June 2017

Zwicker’s psychoacoustic annoyance model can be used to estimate the relative degree of noise annoyance. However, this model cannot be well applied to compare the annoyance degrees of tonal noises and atonal noises. In order to improve its estimation effect on tonal noises, 3 groups of noise samples were selected randomly, i.e., 27 low-frequency tonal noise samples induced by a 1000 kV transformer with A-weighted equivalent sound pressure levels ranging from 41.2 dBA to 73.0 dBA; 30 low-, mid-, or high-frequency tonal/atonal noise samples with loudness levels ranging from 60 phon to 80 phon; and 60 other noise samples with A-weighted equivalent sound pressure levels ranging from 40.7 dBA to 75.0 dBA. Laboratory listening tests were conducted on the above 3 sample groups respectively via an 11-point numerical scale. The Zwicker’s psychoacoustic annoyance model was improved by taking tonality into account, and introducing the evaluation result of the first noise sample group (1000 kV transformer noise samples) to determine the coefficients in the model. The applicability of the improved model was examined by the evaluation results of the other two groups as well as the data in a previous research on annoyance of 220 kV/500 kV transformer noises. Results show that the improved model can estimate the relative annoyance degrees caused by various types of tonal / atonal noises much more accurately.
Clang, chitter, crunch: Perceptual organisation of onomatopoeia
Authors: Bones Oliver C. , Davies William J. , Cox Trevor J.
Published: June 2017

A method has been developed that utilizes a sound-sorting and labeling procedure, with correspondence analysis of participant-generated descriptive terms, to elicit perceptual categories of sound. Unlike many other methods for identifying perceptual categories, this approach allows for the interpretation of participant categorization without the researcher prescribing descriptive terms. The work has allowed robust sound taxonomies to be created, which give insight into categorical auditory processing of everyday sounds by humans. Work on common audio search terms has highlighted that onomatopoeia are an important group that has been largely overlooked in quotidian sound studies. These are words for which the meaning of the word maps onto the sound of the utterance, and are an example of sound symbolism where there is a non-arbitrary link between the form and the meaning of word. Early analysis of the data suggests that people do draw on sound symbolism to carry out the categorization, but that in addition they also draw similarities between the inferred sound sources, such as organic versus non-organic.
Perception of environmental sounds: Recognition-detection gaps
Authors: Miskiewicz Andrzej , Rosciszewska Teresa , Majer Jacek
Published: June 2017

The study was conducted to assess the detection and recognition thresholds for 16 selected environmental sounds and determine the sound pressure level difference between those thresholds, called the recognition-detection gap (RDG). The sounds were recorded with a dummy head and played back through headphones. Recognition and detection thresholds were measured for two groups of listeners—musicians and non-musicians, in two conditions: in quiet and in the presence of multitalker masking noise added to the signal. The results demonstrate that RDG considerably varies, depending on the acoustic characteristics the sound, from about 2 to as much as 20 dB for sounds that are particularly difficult to recognize. The difficulty with which a listener recognizes the sounds, assessed on the basis of RDG, is also reflected by the steepness of psychometric functions for recognition. The present findings do not support a working hypothesis in which it was assumed that musical training results in an enhancement of the ability to recognize sounds at levels close to detection threshold, when not all their acoustic signatures are clearly audible, and manifests itself in smaller RDGs.
Psychoacoustic sonification for tracked medical instrument guidance
Authors: Ziemer Tim , Black David
Published: June 2017

In image-guided surgery, displays show a tracked instrument relative to a patient's anatomy. This helps the surgeon to follow a predefined path with a scalpel or to avoid risk structures. A psychoacoustically motivated sonification design is presented to help assist surgeons in navigating a tracked instrument to a target location in two-dimensional space. This is achieved by mapping spatial dimensions to audio parameters that affect the magnitude of different perceptual sound qualities. Horizontal distance and direction are mapped to glissando speed and direction of a Shepard tone. The vertical dimension is divided into two regions. Below the target, the vertical distance controls the LFO speed of an amplitude modulation to create a regular beating well below the threshold of roughness sensation. Above the target elevation, the vertical deflection controls the depth of frequency modulation to gradually increase the number and amplitudes of sidebands, affecting perceived noisiness and roughness. This redundancy is necessary because the magnitudes of each single sound quality are only differentiable with little confidence. In a preliminary study, non-surgeons successfully identified a target field out of 16 possible fields in 41% of all trials. The correct cardinal direction was identified in 84%. Based on findings and further psychoacoustic considerations, the mapping range is optimized and an implementation of an additional depth dimension is discussed.
Radiosity and radiative transfer in sound and vibration
Authors: Le Bot Alain
Published: June 2017

At high frequencies in acoustics, the most popular method is ray-tracing and its variants including radiosity. In structural vibrations, the most known method is rather statistical energy analysis [1]. Both methods may be derived from a unique approach based on radiative transfer equations analogous to radiative exchanges of energy in thermics [2]. In this study, we present an overview of the radiative transfer equations in sound and vibration. We first show that radiosity is equivalent to ray-tracing with Lambertian reflection. In steady-state condition, radiosity is strictly equivalent to the view factor method in thermics. But in transient condition, radiosity provides an elegant solution to predict reverberation beyond the validity of Sabine's law. The theory is also well suited for structural rays in built-up structures. The radiative transfer equations account for reflection and transmission at interfaces of structural components. Sound radiation may also be described in the limit of high frequencies by this approach. It is also shown that a radiative transfer equation may include diffraction in a simple way. Simple and multiple diffraction by corners can be predicted. For all these phenomena, some numerical examples are presented to illustrate the relevance of the approach. [1] Foundation of statistical energy analysis in vibroacoustics, A. Le Bot. Oxford University Press, Oxford UK, 2015. [2] High frequency vibroacoustics: a radiative transfer equation and radiosity based approach, A. Le Bot, E. Reboul, Wave Motion, 2014.
A regression-based energy method for predicting structural vibration and interior noise
Authors: Sung Shung H. , Nefske Donald J.
Published: June 2017

A regression-based energy method is developed for predicting the structural vibration and interior noise for prescribed loads applied to a structural-acoustic enclosure subject to differences in the structural or acoustic design. The formulation is based on the energy transfer functions that relate the applied load energy to the structural or acoustic response energy. The energy transfer functions are determined from a statistical regression analysis of the measured or predicted multiple responses that result from the differences in the structural or acoustic design. The applied load energy is determined analytically or experimentally for prescribed loading conditions. The energy method can then be used to estimate the mean-value and variation of the structural or acoustic response for different structural or acoustic designs and various prescribed loading inputs. A simple tube-mass-spring-damper system terminated with absorption material with variation is presented as an example. The practical application of the method to estimate the interior noise in an automotive vehicle for road and aerodynamic loads at different speeds is then presented. Comparisons of the predicted versus measured mean-value and variation of the sound pressure response show reasonable agreement. The methodology is generally applicable for rapidly estimating the structural or acoustic response for different designs and various loading conditions.
High frequency analysis of a point-coupled parallel plate system
Authors: Culver Dean R. , Dowell Earl
Published: June 2017

The RMS response of various points in a system comprised of two parallel plates coupled at a point undergoing high frequency, broadband transverse point excitation of one component is considered. Through this prototypical example, Asymptotic Modal Analysis (AMA) is extended to two coupled continuous dynamical systems. It is shown that different points on the plates respond with different RMS magnitudes depending on their spatial relationship to the excitation or coupling points in the system. The ability of AMA to accurately compute the RMS response of these points (namely the excitation point, the coupling points, and the hot lines through the excitation or coupling points) in the system is shown. The behavior of three representative prototypical configurations of the parallel plate system: two similar plates (in both geometry and modal density), two plates with similar modal density but different geometry, and two plates with similar geometry but different modal density. After examining the error between reduced modal methods (such as AMA) to Classical Modal Analysis (CMA), it is determined that these several methods are valid for each of these scenarios. The data from the various methods will also be useful in evaluating the accuracy of other methods including SEA.
General thermodynamics of vibrating systems
Authors: Carcaterra Antonio
Published: June 2017

This paper introduces a general view of a generalized thermodynamic theory for vibrating systems, with special emphasis to vibration and acoustics applications. One of the basis, is the temperature concept for Hamiltonian systems to describe the energy flow between two coupled sub-systems. As a result, a general and strict method to approach the energy analysis of linear and nonlinear systems, with potential applications both in theoretical mechanics as well as in engineering vibroacoustics and Statistical Energy Analysis is disclosed. The opportunity of a strict mathematical foundation to this important physical and engineering problem, is provided by the introduction of the Khinchin’s entropy. The analysis shows that, under (i) linearity, (ii) weak coupling, and (iii) close-to-equilibrium conditions, a Fourier-like heat transmission law is obtained, where the thermodynamic temperature in proportional to the modal energy of the system, that is the ratio of its total energy and the number of its degrees of freedom. Generalized results both for large shocks and for nonlinear systems are indeed derived in closed form for weak anharmonic potentials, showing in this case that the temperature depends on a series of integer and fractional powers of the system’s modal energy. At the end, a generalized statistical energy analysis of nonlinear systems is outlined.