bluuebunny/crossref_metadata_2025 huggingface dataset:
Seasonal and diurnal presence of finless porpoises at the corridor to the ocean from a semi-closed bay habitat.
Authors: Akamatsu Tomonari , Nakamura Kiyomi , Kawabe Ryo , Furukawa Seishiro , Murata Hiromi , Kawakubo Akihiro , Komaba Masayuki
Published: March 2010

Finless porpoises in Omura Bay is the smallest among five populations in Japanese waters. This is a newly established population after the global warming of 9000 years ago, consisting of approximately 300 individuals and believed to be confined in Omura Bay. At the major corridor to the ocean from this bay, presence of finless porpoises was monitored acoustically from November 2007 to May 2009. A stereo acoustic event recorder (A-tag) was deployed at this strait. A-tag stored the intensity and the sound source direction of biosonar signals that provides independent traces of sound source corresponding to each animal. During 1.5 year observation, 226 individuals of porpoises were detected. Of them, 76% were presented at night and 73% observed during March to April. In the same season, anchovy landings in the Omura bay was recorded. 70% percent of the porpoises were observed during the tidal current that went out of Omura Bay that suggests the porpoises swam back and forth around the monitoring station. Although finless porpoises have been known to be confined in a local area, occasional migration of this species induced by prey availability might extend their habitat at different waters in Asian coasts.
Fractional wave equation for compressional and shear waves.
Authors: Holm S. , Sinkus R.
Published: March 2010

This study has been motivated by the observed difference in the range of the power law attenuation exponent for compressional and shear waves. Usually compressional attenuation increases with frequency to a power between 1 and 2, while shear wave attenuation often is described with powers less than 1. Another motivation is the apparent lack of partial differential equations with desirable properties such as causality that describe such wave propagation. Starting with a constitutive equation which is generalized Hooke’s law with a loss term containing a fractional derivative, one can derive a causal fractional wave equation previously given by Caputo (1967) and Wismer (2006). In the low ωτ (low-frequency) case, this equation has an attenuation with a power law in the range from 1 to 2. This is consistent with, e.g., attenuation in tissue. In the often neglected high ωτ (high-frequency) case, it describes attenuation with a power law between 0 and 1, consistent with what is observed in, e.g., dynamic elastography. Thus a unifying wave equation derived properly from constitutive equations can describe both cases. Recent results on fractional random media will also be discussed as they give similar characteristics from a microperspective.
Strategies to improve conformal tumor heating with waveform diversity beamforming.
Authors: McGough Robert J. , Jennings Matthew R.
Published: March 2010

Waveform diversity is a phased array beamforming approach that, when applied to tumor heating with ultrasound, simultaneously maximizes the power at control points in the tumor while minimizing the power deposited in specified sensitive tissues. When waveform diversity calculations are combined with a rank deficient beamforming method, the optimal number of focal patterns is determined, and the optimal array excitations are also obtained. Previous results have shown that waveform diversity combined with mode scanning reduces problems with intervening tissue heating that otherwise occur when standard spot scanning approaches are applied. In an effort to extend these results and achieve a more conformal tumor heat deposition, variable weights will be applied to each of the focal points as a function of distance from the center of the spherical tumor volume. Modified focal point arrangements that decrease the focal point density along the array normal to further reduce normal tissue heating will also be evaluated. Simulations demonstrating the results of these and other modified beamforming strategies will be demonstrated for a large spherical section array using the FOCUS software package.
Remote construction noise monitoring.
Authors: Gharabegian Areg
Published: March 2010

Los Angeles was constructing an underground 12 ft in diameter sewage tunnel stretching 25 km. The project includes nine construction access shafts where tunnel boring machines, muck trains, and materials were lowered into the ground. The excavated tunnel material was transported from the tunnel head to the access shafts by muck train, removed by a crane, and carried away via heavy haul trucks. A state of art remote construction noise system was developed and installed near each of the shaft sites, which was collecting noise, audio, and video data 24 h a day. Noise levels were recorded whenever a noise limit threshold is exceeded. Data were then transmitted via modem to a central location where noise specialists review and analyze the data. A portion of these noise limit exceedances were correlated to the audio and video files to determine if the exceedances were due to the construction activities or other non-construction related events. Construction noise at the noise sensitive sites adjacent to each shaft were minimized by constructing sound walls as high as 10 m.
An approach to noise impact assessment for long-term construction.
Authors: Babic Frank
Published: March 2010

Noise generated by construction is typically characterized as a temporary noise source. Due to its temporary nature, construction noise can generally be tolerated by the community at large more readily than long-term noise sources (for example, from industry). For some projects, construction may extend beyond a temporary period to become a more long-term noise problem—especially when the construction activity can last months or even years. When an extended construction period occurs, the community may be less tolerant of the noise, and the assessment of its impact on the community is more aptly characterized as a long-term noise source, similar to that of industry. This paper proposes an approach to assessing long-term construction projects, where a “worst-case” scenario can be modeled with utility factors, duty cycles, and barrier noise controls. From this modeling, a zone of influence can be determined which identifies the extent of the noise impact (i.e., potential complaints generated by nuisance from construction noise). Receptors within this zone of influence (including residences, hospitals, churches, etc.) can then be identified as part of the environmental noise impact assessment for long-term construction activity.
Construction noise impact prediction using non-virtual simulation.
Authors: Greene Rob
Published: March 2010

This paper presents a rarely used approach to predicting potential noise impacts from major infrastructure construction. The method includes the actual propagation of spectrally shaped pink noise into a community from locations within the proposed project’s construction site, coupled with contemporaneous noise measurements at multiple in-community locations. Pre-test source calibration measurements were performed and ambient noise levels were measured in the surrounding community during pre- and post-test periods. A Public Information program was part of the environmental assessment process. Yes, this novel/brave/are you crazy? approach was extensively covered in the local press. The community reaction to the methodology, the noise control mitigation that resulted from the test, the success of the construction, and lessons learned will be presented.
Designing partial enclosures to minimize airborne sound transmission.
Authors: Herrin D. W. , Carter A.E. , Shi J., , Copley D. C.
Published: March 2010

Enclosures are a very common way to reduce noise emissions from machinery. However, enclosures display complex acoustic behavior that is difficult to predict. Boundary element simulation was used to better understand the airborne transmission path for a partial enclosure. Sources considered included a point source and a diesel engine. Insertion loss was used as the performance measure to evaluate the effect of several different design considerations. Results indicate that the most important factors affecting enclosure performance are the opening size, amount of absorption, and the source-to-opening distance. It is notable that insertion loss was relatively insensitive to enclosure or source size.
A relation between flow, noise, and system impedance for notebook computers.
Authors: Baugh Eric
Published: March 2010

Performance of notebook computers is strongly limited by the ability to reject heat from the system. In a typical mainstream design, the airflow driven by the internal fan is responsible for about 80% of the maximum cooling capability, and this airflow impacts all the internal components (CPU, memory, radios, etc.) as well as the top and bottom skin temperatures. Fan flow, in turn, is limited by acoustics. It has been shown that the fan installation conditions inside a notebook computer have an adverse effect on both flow rate and noise. The market trend is toward thinner systems, which generally have a higher system impedance. As impedance increases, system airflow must decrease to maintain a fixed acoustic limit, holding all other variables constant. In order to demonstrate the effect of impedance, this paper describes a simple, two parameter model relating the flow rate in a notebook computer at a given operator position sound pressure level to the impedance index of the system. This relation is shown to reasonably approximate the behavior of about 20 different notebook computers.
The dB[EQL]: An alternative sound pressure weighting according to the equal loudness contours of the international standard ISO 226-2003.
Authors: Bray Wade
Published: March 2010

The conventional spectral weightings applicable to sound pressure [dB(A), etc.] are fixed in spectral shape and intended for use over certain ranges of unweighted sound pressure level: for example, the A-weighting from threshold of hearing up to 65 dB(SPL). In general, these weightings’ spectral shapes match the sensitivity of hearing as a function of frequency within “use-level” ranges, although the strong effect of the cavum conchae resonance of the ear, apparent in the equal-loudness contours of ISO 226, is not considered except in the rarely Used D-weighting. Particularly for sounds with tonal content and within the general level range of the A-weighting, the authors propose a new spectral weighting assembled from the Phon values of the complete set of equal-loudness contours calculated for each frequency within the human auditory range. It will be shown that although giving values similar to those of the A-weighting, the dB[EQL] or equal-loudness weighting is situation dependent rather than fixed, and better represents subjective impressions at all frequencies. Although based on perceived loudnesses, the dB[EQL] sound pressure weighting is not a specific loudness measurement, does not consider critical band formation, and does not yield masking or psychoacoustic loudness data.
Geothermal heat pump noise control (cont.): Its all in the details.
Authors: Fullerton Jeffrey
Published: March 2010

The installation of a geothermal heat pump in the basement of a 1900 era home introduced significant noise and vibration to a bedroom above, which was discussed in detail in a previous conference. After mitigating the noise and vibration using piping isolation products, lower levels of noise and vibration still remained. This paper will discuss pursuits that were implemented and the very effective resolution for mitigating the noise and vibration that was generated by the heat pump.
Application of atmospheric absorption models for aircraft enroute noise.
Authors: Poulain Kieran , Sparrow Victor , Brentner Kenneth , Sutherland Louis
Published: March 2010

Propagation of aircraft enroute noise for flights above 18 000 ft above ground level (AGL) (5.49 km AGL) is important for estimating noise impact in U.S. National Parks and other quiet areas. One key to the accurate estimation of noise impact is atmospheric absorption. In our atmosphere, it turns out that the absorption coefficient is dependent on altitude as well as frequency. The altitude dependent parameters include mean pressure, temperature, and relative humidity as well as the concentration of molecular species. This altitude effect can be important for certain frequency bands, and this point will be emphasized in this paper. In addition, an improved atmospheric absorption model for high altitudes of Sutherland and Bass [J. Acoust. Soc. Am. 115, 1012–1032 (2004)] shows slightly different values of atmospheric absorption in important frequency bands for aviation noise at altitude compared to the typical ANSI Standard S1.26-1995 (R 2009). For certain situations, the updated atmospheric absorption coefficient could produce different enroute noise predictions on the ground. [Work supported by FAA/NASA/Transport-Canada PARTNER Center of Excellence.]
Modeling propagation of aviation noise under range-dependent conditions, using a hybrid parabolic equation-fast field program method.
Authors: Rosenbaum Joyce , Atchley Anthony , Sparrow Victor
Published: March 2010

Based on the Parabolic equation method, a model for sound propagation over uneven terrain, with mixed ground impedance and range-dependent meteorological conditions, has been developed to improve prediction of the impact of aviation noise on communities. Intended to enhance the noise prediction capabilities for the Federal Aviation Administration’s Aviation Environmental Design Tool in support of the Next Generation Air Transportation System (NextGen), the model uses a hybrid parabolic equation-fast field program approach for computing aviation noise contours. These methods ensure that the low-frequency content, a factor in community impact, is propagated accurately. The model can accommodate a broadband, moving sound source, traveling along a user-specified path, over three-dimensional terrain. A test case, designed to represent simple but realistic propagation conditions, is described, and results for a source traveling along a simple flight path are presented and discussed.
Modeling of noise from aircraft taxiing operations.
Authors: Page Juliet , Hobbs Christopher
Published: March 2010

This paper documents a study performed for the Airport Cooperative Research Program, investigating noise from aircraft taxi operations. A holistic approach is utilized, applying an understanding of the operations, the detailed aircraft motions, and the acoustic sources. A series of acoustic sensitivity studies was conducted in order to develop a physical understanding of the relative importance of the various modeling elements within the framework of AEDT. The study is based on decoupling the modeling of taxi noise into the following three areas and exercising each element independently. (1) Engine source noise (level, spectra, and directivity); (2) aircraft movements and operating states (location, duration, and power setting); (3) environment/propagation (lateral attenuation, terrain, shielding, and ground impedance). Aircraft taxi noise sensitivity studies exercised each element independently. Limited opportunistic commercial aircraft taxi operation acoustic measurements were conducted. Independent taxi flight data recorder information was queried to determine statistical engine and aircraft operational parameters. The sensitivity studies reveal that the primary weakness for taxi noise modeling is related to item (#1), engine source noise modeling. This paper will discuss the sensitivity study findings and present an approach for development of a nominal taxi state noise noise-power-distance, spectral class, and directivity database for AEDT.
Concrete pier foundation and building design for electron microscope installations with vibration disturbances from train, truck, and bus traffic.
Authors: Himmel Chad
Published: March 2010

A university microscopy and imaging center housing nine instruments including scanning electron microscopes and transmission electron microscopes was proposed for a site near an active railroad and roadways. Low-frequency sound and vibration from trains, trucks, and buses can affect the performance and use of electron microscopes, by disturbing the stability and resolution of the specimen’s image. On-site observations and spectrum measurements were conducted to determine the ambient and transient ground borne vibration conditions. Measurements showed that disturbances from trains as well as bus and truck traffic on campus roads significantly exceeded allowable floor vibration tolerances for many of the instruments. Soils exhibited response to disturbances at dominant frequencies around 5 and 10 Hz. This paper addresses the potential for concrete pier-supported floor vibration and structural resonance contributions to ground borne vibration levels and solutions proposed to mitigate the disturbances for sensitive instrument installations. Graphic diagrams of structural design concepts and results from on-site measurements prior to construction will be discussed. The designs and effectiveness of the microscope rooms, structural treatments, and actively damped, pneumatic vibration isolation systems are discussed, along with post-construction vibration measurement results and photographs.
Tri-axial measurement of roadway vibration in multiple research buildings located throughout an urban college campus.
Authors: Harvey Scott , Curley Josh
Published: March 2010

Plans are currently underway to run a mass transit rail line through the center of a major university. Concerns over this significant change to the school’s infrastructure were raised by members of the university’s faculty, particularly professors questioning whether their research projects and vibration sensitive equipment will be disturbed from vibration generated by all the new train passbys. A study was arranged to investigate the campus existing vibration levels and analyze the potential for a substantial increase in vibration once the rail line is constructed. This was primarily a measure of vibration from traffic sources, especially university buses which operate frequently throughout the campus during all hours. The project involved recording simultaneous tri-axial vibration measurements in numerous locations throughout the campus. This required designing methods to manage equipment, make measurements, organize data, and present results in an efficient, timely, and coherent manner. The data indicate the level of ambient ground and structural vibration already present from daily university activities while serving as a basis for comparison to the increased vibration levels, if any, the newly constructed train will cause.
Reduction of blade passing noise of a vertical take-off and landing (VTOL) aircraft.
Authors: Pan Jie , Sun Hongmei , Walsh B. S. , Do K. D. , ONeill P. , Ranasinghe J.
Published: March 2010

Rotor-stator interaction has been identified as the dominant noise source of a vertical take-off and landing (VTOL) aircraft developed by Entecho. This paper reports field measurement results of blade passing noise of the VTOL air-craft together with its analysis and control. The blade passing event was simulated in a wind tunnel experiment. The flow speed, rotor position, and rotor-stator spacing were varied with the chord-wise pressure distribution of the lead-ing surface of the rotor blade being measured by an array of six flush mounted microphones. Results show useful features of the pressure distribution on the rotor blade influenced by an upstream stator, which are used for the analysis and prediction of the sound radiation from the VTOL aircraft. The preliminary result of the reduction in the blade passing noise using angled stator blades is also presented.
Prediction of axial fan noise by linearized perturbed compressible equations with large eddy simulation.
Authors: Moon Young J. , Kim Hoyeon , Bae Youngmin , Ravelet Florent , Khelladi Sofiane , Nouri Hussain , Bakir Farid
Published: March 2010

The seek for an efficient aerodynamic and aeroacoustic design of axial-flow fans is an important field of investigation for both academic and applied research. Improvements can only be made with a better understanding of the physical mechanisms arising in these machines that combine strong interactions between rotating and non-rotating parts of highly complex geometries. One way is to couple well-suited experimental investigations and innovative computational methods that overtake the weaknesses of methods based, for instance, on aeroacoustic analogy. In this paper we study an axial fan using a new numerical method based on large eddy simulation/linearized perturbed compressible equations with Brinkman penalization. This method is developed in the Department of Mechanical Engineering at Korea University. The experimental tests and validations are performed in the Laboratory of Fluid Dynamics at Arts & Métiers ParisTech in Paris. Detailed analysis of numerical and experimental results is in progress within the two partner teams.
The near-field of spinning sources: Why source identification is hard.
Authors: Carley M. J.
Published: March 2010

An asymptotic analysis is presented for the near field of spinning sources, based on a transformation into cylindrical coordinates centered on a line at a fixed radius from the source axis. This transforms the circular source into an equivalent finite length line source with a source distribution made up of “modes” given as Chebyshev polynomials of the second kind Un(s) = sin[(n + 1)cos−1 s]/sin cos−1 s. These modes play a role like that of modes in ducts and the analysis shows that their acoustic field propagates or decays depending on whether n + 1 < k or n + 1 ≥ k, respectively, with k wavenumber, similar to the cut-on/cut-off behavior of duct modes. The analysis is used to examine the problem of identifying a source from field measurements. This has a wide range of applications in many industrial fields but is well known to be (very) ill conditioned. Using the information supplied by the analysis of the source near field, the reasons for this ill conditioning are explained and some possible methods to mitigate the problem are outlined.
Toward the prediction of fan noise: From low-speed to high-speed turbomachineries.
Authors: Moreau Stphane
Published: March 2010

Environmental concern and comfort trigger more and more acoustic specifications and regulations on aircraft impact on airports and on ventilation systems in buildings or transportation systems (cars, trains, or airplanes), which in turn impose lower and lower maximum noise levels to such systems. For instance, turbofan engines have increased their bypass ratio in order to improve the aircraft performance while diminishing the nominal speed of rotation. The jet noise is then reduced, and the fan noise becomes a dominant source of noise, especially at approach. A quick calculation of the overall noise generated by a given fan geometry, either low speed or high speed, would be a valuable asset to any fan design designer and manufacturer prior to any installation in a building or an airplane, for instance. However, an accurate prediction of the sound by any full turbomachinery still remains a challenging goal and a daunting task to be achieved by a direct computation. In the present study, the noise predictions will then rely on a strip theory combined with an acoustic analogy based on the wall pressure fluctuations. For the low-speed fans, the model is an extension of the development by Schlinker & Amiet for helicopters. Turbofan engines induce two additional difficulties to noise modeling: the cascade effects and the duct configuration which are presently modeled.
Quiet, efficient fans for space flight: An overview of NASA’s technology development plan.
Authors: Koch Danielle
Published: March 2010

NASA has developed a Technology Development Plan for improving the aerodynamic and acoustic performance of spaceflight fans. The intent is to make broader use of the technology developed at NASA Glenn to improve the efficiency and reduce the noise of aircraft engine fans. The goal is to develop a set of well-characterized government-owned fans nominally suited for spacecraft ventilation and cooling systems. NASA’s Exploration Life Support community will identify design point conditions for the fans in this study. Computational Fluid Dynamics codes will be used in the design and analysis process. The fans will be built and used in a series of tests. Data from aerodynamic and acoustic performance tests will be used to validate performance predictions. These performance maps will also be entered into a database to help spaceflight fan system developers make informed design choices. Velocity measurements downstream of fan rotor blades and stator vanes will also be collected and used for code validation. Details of the fan design, analysis, and testing will be publicly reported. With access to fan geometry and test data, the small fan industry can independently evaluate design and analysis methods and work toward improvement.
Aerodynamic design and computational analysis of a space flight vehicle cabin ventilation fan.
Authors: Tweedt Daniel L.
Published: March 2010

Quieter working environments for astronauts are needed if future long-duration space exploration missions are to be safe and productive. Ventilation and payload cooling fans are known to be dominant sources of noise, with the International Space Station being an important case in point. To address this issue in a cost effective way, early attention to fan design, selection, and installation has been recommended. Toward that end, NASA has begun to investigate the potential for small-fan noise reduction through improvements in fan aerodynamic design. Using tools and methodologies similar to those employed by the aircraft engine industry, the aerodynamic design of a new cabin ventilation fan has been developed, and its aerodynamic performance predicted using computational fluid dynamics (CFD) codes. The design, intended to serve as a baseline for future work, is discussed along with selected CFD results.
Cooling fan noise reduction by optimizing spacing of blades.
Authors: Wang John
Published: March 2010

Cooling fan noise theories are briefly reviewed. A simplified model is derived from a rotating point source theory. Optimization was done using the simplified model. A fan with unevenly spaced blades was prototyped, tested, and compared with a fan with evenly spaced blades. Noise reduction data are presented.
Suppression of ducted dipole noise by an expanded segment around the source.
Authors: Huang Lixi
Published: March 2010

Low-speed fan noise mainly features dipole sound radiation. For such a fan operating in a duct, the low- to medium-frequency radiation derives mainly from the unsteady, axial forces acting on the rotating blades. Recently, we have found, both theoretically and experimentally, that self-cancellation of sound can be achieved by placing the dipole in an expanded segment of the duct which provides a reverberating environment with a reduced radiation impedance. The insertion loss spectrum shows a very broadband appearance similar to but is better than the transmission loss spectrum of an expansion chamber silencers used for reflecting an incident plane wave. Parametric analysis reveals that the expansion ratio controls the peak insertion loss, while the chamber length controls the single-lobe bandwidth. Simple plane wave analysis implies that short chamber would give wider stopband with a chamber of vanishing length yielding the best result. It is shown here that such analysis fails when the chamber is too short. For a given finite frequency band, there exists an optimal chamber length. Spectral element analysis reveals details of such optimal length and the result is explained in terms of the known fundamentals of dipole radiation and duct acoustics.
Active control of axial fan noise using a multiple-input multiple-output feedback controller.
Authors: Duke Cole V. , Sommerfeldt Scott D. , Gee Kent L.
Published: March 2010

In the past, significant progress has been made in actively controlling the tonal noise of axial cooling fans using a digital, feed-forward controller. Progress has also been made in controlling broadband fan noise using an analog feedback controller due to the nondeterministic nature of the noise. Current work focuses on the control of broadband noise with a multiple-input multiple-output (MIMO) feedback controller using four control sources and four error sensors. To ensure stability of the closed-loop control system, the phase and magnitude characteristics of the controller must be chosen to produce attenuation in the target frequency band without augmenting the noise outside the band. A practical analog feedback controller will be presented, and performance results will be compared between a single-input single-output controller and a MIMO controller.
Addressing concerns about ultrasound noise during expansion of a laboratory animal facility.
Authors: Glickman Gary M.
Published: March 2010

Since 2002 the mouse has become the preferred model for biomedical research largely due to the ease with which it can be genetically engineered. The growth in genetic research has led many institutions to expand their animal holding and research facilities. Managing expectations of investigators during the process of construction and minimizing potential for noise impacts to research are critical for a successful expansion project. Noise in the ultrasound frequency range is often a concern among researchers due to limited data on its causes and response of mice to it and due to the fact that humans cannot perceive ultrasound and are therefore unable to detect when it occurs. Consequently, prior to and during construction, issues involving ultrasound are best given careful consideration so as to minimize it and at the same time address researcher’s concerns. Work will be presented from a case study of an expansion project at a medical research facility involving transgenic mice. Issues surrounding the potential for construction noise to impact mice holding rooms will be examined. Particular attention will be paid to measurement and evaluation of noise at ultrasound frequencies and approaches for addressing the concerns of investigators.
Extraction of hearing loss threshold levels and equal auditory risk metric curves of chinchillas from existing exposure data.
Authors: Song Wonjoon , Goley Steve , Kim Jay
Published: March 2010

An existing set of chinchilla noise exposure data has been re-analyzed using an advanced signal analysis tool and a statistical regression analysis. The data are comprised of 23 digitally recorded noise files and auditory damage indicators of the chinchillas measured at six frequency points, 0.5, 1, 2, 4, 8, and 16 kHz. From the relationship between the equivalent sound pressure level (Leq) of the six 1/3 octave frequency components of the noise and PTS of chinchillas, the Leq level that starts to cause auditory damage to chinchillas is identified as a function of frequency. These threshold levels of chinchillas, obtained for the first time in this study, will be useful information to design chinchilla exposure studies. The levels that will cause the same amount of PTS at the six frequencies are also obtained, from which equal auditory risk metric (EARM) curves are constructed. It is shown that a chinchilla version of an advanced noise guideline which enables quantitative, frequency-by-frequency assessment of the risk of a noise can be developed using the EARM curves. Possibility as well as difficulties of developing a human version guideline similar to this chinchilla prototype are discussed.
Hearing protection devices: The regulatory journey to change.
Authors: Jefferson Catrice
Published: March 2010

The regulation for the labeling of hearing protection devices (40 CFR Part 211, Subpart B) was promulgated in 1979 and has been the directive for 30 years. During this time, there have been significant changes in the industry with respect to newly developed products, which has resulted in the demand for various types of hearing protectors and an increased awareness of hearing loss in both occupational and non-occupational environments. The foundation of the newly proposed regulation of August 5, 2009 is based on these observations and those that were presented by industry, hearing conservation professionals, and the general public during the EPA Workshop on Hearing Protection Devices that was held in March 2003. While these observations will serve as the backdrop of the presentation, the scenery will be the key elements of the proposed regulation, such as the testing methodology, noise reduction rating range, label format and content, recurrent testing, and reporting requirements of testing data. The audience will journey through these scenic elements but will be delivered to its final destination, which are regulatory change and the prospects of withstanding another 30 years.
Proposal for assessing the effectiveness of noise policies.
Authors: Finegold Lawrence , So Finegold Michiko
Published: March 2010

During the last half of the 20th century, most of the developed countries of the world have been addressing noise as an environmental and occupational problem, and have been working to develop noise control and exposure policies and related noise control technologies. Since the 1970s, the United States has been an international leader in these efforts, although more recently significant advances have been made elsewhere, particularly by the European Commission. However, little is known about how effective various noise policies and regulations have been in controlling the noise exposure of the populations which they are intended to protect. This paper proposes a national program to address this issue. The first phase involves the collection and cataloging of noise policy regulations and related guidelines and, for the most part, has already been completed by the International Institute of Noise Control Engineering, including a comprehensive index of U.S. noise policies. The second phase would involve developing a baseline of noise exposure estimates for various community environments. The third phase would determine the long-term effectiveness of noise policies in controlling noise exposure by examining the changes in various noise exposures and noise effects over time.
Integrating disturbance ecology and public policy: A better framework for managing the effects of anthropogenic noise.
Authors: Bowles Ann E. , Scholik-Schlomer Amy R.
Published: March 2010

The Marine Mammal Protection Act and the Endangered Species Act are statutes designed to conserve and recover marine mammal species. In addition to language that restricts activities that could “take” individuals via death, they restrict activities that could harass marine mammals. By framing the problem in terms of harassment, these statutes acknowledge the potential for significant behavioral effects. However, predicting biologically significant effects of disturbance is often difficult. A better theoretical and technical framework is needed that accounts for the adaptive scope (both physiological and behavioral) of large, intelligent, wide-ranging, and long-lived marine mammals. While ASA members have debated policy statements on the inappropriate use of acoustic concepts in controversies over marine mammal exposure to noise, they have not effectively addressed the need for better integration of biological theory. Of particular importance are theories on cognitive function, adaptive defensive strategies, and allostasis that help explain why marine mammal responses can be intelligent and flexible in some cases and injurious in others. By integrating such biological concepts into its policy statements, the Society could foster more effective use of research resources and help stakeholders support regulatory instruments for noise that would effectively balance human needs with those of marine mammals.
Sex, money, religion, and politics: Understanding noise policy in terms of what is left unsaid.
Authors: Blomberg Leslie D.
Published: March 2010

Sex, money, religion, and politics. We are not supposed to talk about these things. And when it comes to discussions of creating a comprehensive noise policy, we generally do not, and perhaps we should not. But we should at least understand their contribution to the mxe9;lange of laws and regulations that is our current noise policy. This paper examines the elephant in the room that people are not talking about.
There ought to be a law!
Authors: Timmerman Nancy S.
Published: March 2010

This paper will examine some of the logical consequences of laws and policymaking as they relate to acoustics. In acoustics and noise control, “public policy” is used to try to legislate good behavior. Those who behave well do not need the laws. Those who do not will not obey the laws. Examples will be drawn from aviation and planning, examining the use of measures such as DNL. In particular, this paper will address how laws create unintended results, frequently not addressing the issue at all.
New York City: The (E) designation and restrictive declaration.
Authors: Sachwald Benjamin
Published: March 2010

Urban areas are typically associated with high-noise levels. With a population of more than 8×106 and growing, New York City is one of the largest cities in the world. In New York City, because of the population density and the wide variety of land uses (for example, residential, commercial, transportation, manufacturing, and industrial) that exist in close proximity, it is common for a residential building to be located in an area with ambient noise levels that would be considered unsuitable for residential use. To protect inhabitants of a planned building to be located in an area with high ambient noise levels, an (E) designation or a Restrictive Declaration may be used to ensure that the building’s interior environment meet a certain acoustical design criterion. In this paper, the (E) designation and Restrictive Declaration are defined, their regulatory process is outlined, and specific case studies are discussed.
Recommendations for the improvement of the management of noise from helicopter operations.
Authors: Kendrick Paul , Waddington David C. , Kerry Geoff , Muirhead Matthew , Browne Ray
Published: March 2010

This paper results from recent research commissioned by the Department for Environment, Food and Rural Affairs (Defra, UK) with the objective of identifying possible opportunities for the improvement of the management of noise from helicopter operations in the UK. Effected populations are not just those living close to heliports but include those exposed to noise from helicopters used by the military, emergency services, and commercial companies. A detailed report has been produced addressing the improvement of the management of helicopter noise. Also produced was a short non-technical guide including the means of redress for perceived disturbance. The report also makes clear recommendations for future work and identifies particular areas where specific research is required. This paper discusses these recommendations and suggests a way forward for research into the improvement of the management of helicopter noise. [Work funded by the Department for Environment, Food and Rural Affairs (Defra), UK].
Training graduate students: The teaching philosophy of Mack Breazeale.
Authors: McPherson Michael S.
Published: March 2010

Mack Breazeale’s last Ph.D. student will comment on Dr. Breazeale’s contributions to solid state acoustics, nonlinear acoustics, and acousto-optics. In particular, this talk will focus on Dr. Breazeale’s approach to, and methodology for, training and teaching graduate students how to conduct research and mature into capable scientists. This talk will speak to Dr. Breazeale’s unique gifts as a teacher and mentor and his approach to conducting scientific work in general.
Research on acoustical memory discovered in the laboratory of Mack Breazeale.
Authors: Ostrovskii Igor
Published: March 2010

Research at Mack’s Laboratory at NCPA has discovered that a LiNbO3 single crystal can memorize an ultrasonic pulse for tens of microseconds, the frequency range was 17–28 MHz. Supposedly, the Acoustical Memory (AM) effect is connected to the oxide internal microstructures. This conclusion is based on frequency, thermal, and ultrasound attenuation data. Mack Breazeale’s leadership, scholarly character, and gentle nature were clearly revealed through these experimental investigations, various meetings, and scientific discussions in his office and laboratory. However, a basic connection between the ceramic microstructures and AM formation is not revealed yet. Further development of AM investigations is done in the inversely poled ferroelectric wafers of LiNbO3 and LiTaO3. The speeds of different acoustic modes are altered in the presence of periodically poled ferroelectric domains. Calculations for a bulk periodically poled LiNbO3 yield a similar result despite the uniform acoustic properties along the specimen. Distortions in the dispersion curves of ultrasound in non-homogeneous ferroelectrics with specific internal microstructures may be a physical cause of acoustical memory. Some applications are discussed. [Work supported by UM.]
Breazeale legacy in Gaussian acoustics.
Authors: Huang Dehua
Published: March 2010

Professor Breazeale is a great educator, an outstanding researcher, and scientist in many acoustic fields. This talk focuses professor efforts and leadership in pioneer Gaussian acoustics theory and practice. In 1992, instead of going by KZK or Helmholtz equations for theoretical Gaussian acoustic wave solution, a new path was discovered based on the far field approximation from the Rayleigh integral. By which, the mathematical solution matches with the other Gaussian wave equation results. Further, the design of the Gaussian acoustic transducer technologies is evolved. It was only possible for 2 MHz and above frequency band operating Gaussian transducers. This frequency band barrier was crossed over, and a set of kilohertz Gaussian transducers was fabricated in the laboratory by a new design. The definition for a qualified Gaussian transducer was also finalized. The propagation of a Gaussian wave in an ocean environment was also simulated.
Infrasound-convection instability.
Authors: Naugolnykh Konstantin
Published: March 2010

Heated below temperature stratified atmospheric layer is unstable and convection flow can be developed in such an area. Convection happens because warm less dense air goes up while cooler air comes down. Infrasound can initiate convection flow and being amplified by the flow. The process of infrasound-convection interaction is considered in the present paper. The model of convection in a compressible fluid is considered and analyzed. The conditions of infrasound amplification are obtained.
The application of auditory models to hearing aid research.
Authors: Edwards Brent W.
Published: March 2010

Audibility has been a focus of hearing aid research for much of the hearing aid field’s existence. With modern hearing aids, audibility no longer limits performance for hearing aid wearers with moderate hearing impairment. Limitations in suprathreshold auditoryperception now need to be better understood in order to determine existing hearing deficits while aided. The ways in which hearing aids affect suprathreshold auditory function also need to be better understood in order to ensure that hearing aids provide maximal benefit in complex real-world situations. Auditory models can be used to address these needs. This talk will review current applications and future opportunities for the application of auditory models to hearing aid research.
Differentiating inner from outer hair cell damage: Measures and applications to model-based hearing aid design and fitting.
Authors: Lopez-Poveda Enrique A. , Johannesen Peter T. , Prez-González Patricia , Mndez Jorge M. , Eustaquio-Martín Almudena
Published: March 2010

Hearing aids (HAs) are designed and fitted mainly to restore normal audibility and loudness growth. Unfortunately, after decades of research, many users still find them frustrating. We hypothesize that this is partly because HAs operate on the assumption that cochlear hearing loss is always associated with a reduction in cochlear gain and/or compression when this, in fact, need not be the case. Indeed, recent studies have shown that cochlear hearing loss frequently relates to selective or combined dysfunction of inner hair cells (IHCs) and outer hair cells (OHCs). Neither absolute thresholds nor loudness growth allows for a differential assessment of the type of hair cell damage, yet such assessment could be highly informative for optimizing HA design and fitting. In this presentation, we summarize our progress in designing a fast, universal method for inferring the degree of IHC and OHC dysfunction using distortion-product otoacoustic emission input/output functions. We also describe our progress in designing a HA based on these ideas and on a bank of dual-resonance non-linear filters inspired by computational models of healthy and impaired human cochlear responses. [Work supported by the MEC, Grant BFU2006-07536, and The Oticon Foundation.]
The use of a loudness model to derive initial fittings of multi-channel compression hearing aids.
Authors: Moore Brian C. J.
Published: March 2010

A model of loudness perception applicable to hearing-impaired people has been used to develop three methods for the initial fitting of hearing aids with multi-channel compression, based on the audiometric thresholds. Method one, CAMEQ, has the goals of amplifying speech so that, on average, the specific loudness is the same for all frequencies within the range 500–4000 Hz, over a wide range of overall sound levels, giving about the same overall loudness as “normal” for speech covering a wide range of sound levels. Method two, CAMREST, determines the gains needed give normal specific loudness patterns for speech over a wide range of sound levels. Method three, CAMEQ2-HF, is similar to CAMEQ but differs from it in the following ways: (1) gains are recommended for center frequencies up to 10 kHz (as compared to 6 kHz for CAMEQ), (2) CAMEQ2-HF is based on the assumption that the user may wish to hear sounds from many directions and uses a diffuse-field-to-eardrum transfer function (as opposed to a free-field-to-eardrum transfer function for CAMEQ); (3) CAMEQ2-HF is based on recent wideband measurements of the average spectrum of speech. All of the methods can be applied to any multi-channel compression hearing aid.
Application of auditory models to assessing the sound quality of hearing aid signal processing algorithms.
Authors: Hohmann Volker
Published: March 2010

Advances in systems technology allow for increasingly complex processing algorithms in hearing systems addressing increasingly complex acoustic conditions. These developments have the potential of improving the rehabilitation of hearing impairment, but establishing reliable measures of benefit is quite difficult for these complex algorithms and conditions. Being the “gold standard” for algorithm evaluation, subjective testing of hearing-impaired subjects has some limitations in this context. It is very time consuming and the long acclimatization time needed when listening with new devices in complex acoustic conditions cannot easily be accounted for. Therefore, objective methods for estimating the benefit of an algorithm in a certain acoustic condition are desirable. They allow for identifying promising candidate algorithms and the acoustic conditions in which the algorithms might be applicable and thus identify critical acoustic conditions to be tested subjectively. In addition and in combination with technical measures such as segmental signal-to-noise ratio and distortion measures, perceptual measures based on auditory models might be useful for developing meaningful objective measures. This talk presents recent applications of auditory models to objective algorithm evaluation. Because of the growing importance of binaural and multi-microphone processing in hearing instruments, binaural/multichannel models for speech intelligibility and quality will be emphasized.