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22nd National Conference on Noise Control Engineering, NOISE-CON 2007

作者： Nickerson, Matthew Hodgdon, Kathleen Gabrielson, Thomas Atchley, Anthony Graduate Program in Acoustics Penn State 217 Applied Science Building State College PA 16804 United States Applied Research Laboratory Penn State PO Box 30 State College PA 16804 United States

ISBN: (纸本)9781604238525

A low-frequency noise study was performed to investigate human response to the low-frequency content of aviation noise. High levels of noise can impact communities surrounding airports. Current predictive noise models and metrics may underestimate the impact of low-frequency noise (LFN) produced by aviation noise. Assessing the role of LFN in affecting human response will provide a better understanding of how this type of noise can impact communities. Indoor recordings of aircraft arrivals and departures at Washington Dulles International Airport (IAD) made in 2004 were used to assess subjective noise annoyance. These recordings variants having different levels of low-frequency noise were reproduced for subjects in the Gulfstream Supersonic Acoustic Signature Simulator II (SASS II);the subjects then rated the signatures for annoyance. Subjective judgments were statistically analyzed and compared between each signature and within each signature set against commonly used objective metrics. Results are shown that all other things being equal higher levels of low-frequency content in aircraft noise can result in increased annoyance in subjects and that the C-weighted sound exposure level correlated with this annoyance response with a coefficient of determination of 90%.

关键词： Noise pollution

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Application of the Maximum Entropy method to estimating parameter distributions for sonar signal processing

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AIP Conference Proceedings 2007年第1期954卷 427-434页

作者： R. L. Culver H. J. Camin J. A. Ballard C. W. Jemmott L. H. Sibul Graduate Program in Acoustics and Applied Research Laboratory The Pennsylvania State University PO Box 30 State College PA 16804

The Maximum Entropy (MaxEnt) method and Bayesian inference have been employed to incorporate environmental knowledge into the signal processor for a sonar detection application. The sonar receiver is a new Estimator‐Correlator structure that requires only that the probability density function (pdf) of the observation conditioned on the signal belongs to the exponential class, a requirement met by application of the MaxEnt method. Random but statistically correct realizations of the environment are constructed from the pdfs, and an acoustic propagation code is used to propagate acoustic energy through each realization of the environment in a Monte Carlo simulation. From the ensemble of received signals, statistical moments of the signal parameters are estimated and the MaxEnt method is again used to construct signal parameter pdfs. Using Bayesian inference, the predicted parameter pdfs are incorporated into the detection algorithm as a priori information. To evaluate the fidelity of the approach, the statistics of acoustic measurements made during a 1996 experiment in the Strait of Gibraltar are compared with MaxEnt pdfs and simulation predictions.

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Rectangular cymbal arrays for ultrasonic transdermal insulin delivery

Rectangular cymbal arrays for ultrasonic transdermal insulin...

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2007 IEEE Ultrasonics Symposium, IUS

作者： Luis, Joseph Park, Eun-Joo Meyer Jr., Richard J. Smith, Nadine Barrie Graduate Program in Acoustics Pennsylvania State University University Park PA 16802 United States Department of Bioengineering Pennsylvania State University University Park PA 16802 United States Applied Research Laboratory Pennsylvania State University University Park PA 16802 United States

ISBN: (纸本)1424413834

Studies have shown that ultrasound mediated transdermal drug delivery offers a promising potential for needle-less insulin delivery for diabetes treatment. Arrays of cymbal transducers have been shown to be effective in delivering therapeutic levels of insulin to decrease hyperglycemic glucose levels in rats, rabbits and pigs. To improve delivery efficiency of the cymbal arrays, an increase in the spatial intensity field without increasing the size the device or Isptp was desired. A 3 × 1 rectangular cymbal array was designed for this purpose. Rectangular cymbals maximized packing density and allowed the flexural cap resonance and the ceramic length mode resonance frequencies to be designed closer in frequency. Bringing the cap and ceramic resonances closer together increased the transmitting power and improved the electrical efficiency. By using higher order modes excited in the cap while operating at the first ceramic resonance frequency, the intensity spatial area was increased compared to the circular array. With a similar intensity (I sptp ≈ 50 mW/cm2), our goal was to determine if the 3 × 1 rectangular cymbal array could perform significantly better than the 3 × 3 circular array for blood glucose reduction in hyperglycemic rabbits. Nine New Zealand White rabbit (≈ 4.0 kg) experiments were performed in three groups: control (n = 3) and ultrasound exposure with the 3 × 3 circular cymbal array (n = 3) or 3 × 1 rectangular cymbal array (n = 3). The rabbits were anesthetized and their thigh area was shaved for the exposure. A water tight reservoir which held the insulin was fastened between the rabbit's thigh and the ultrasound arrays. At the beginning of the experiment and every 15 minutes for 90 minutes, 0.3 ml of blood was collected from the ear vein to determine the glucose level (mg/dl) using a glucose monitoring system. For comparison between individual rabbits, the change in the blood glucose level was normalized to their initial baseline value. For the cont

关键词： Ultrasonics

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9F-4 Rectangular Cymbal Arrays for Ultrasonic Transdermal Insulin Delivery

9F-4 Rectangular Cymbal Arrays for Ultrasonic Transdermal In...

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IEEE Symposium (IUS) Ultrasonics

作者： J. Luis E.-J. Park R. J. Meyer Jr. N. B. Smith Graduate Program in Acoustics Pennsylvania State University University Park PA USA Department of Bioengineering Pennsylvania State University University Park PA USA Applied Research Laboratory Pennsylvania State University University Park PA USA

Studies have shown that ultrasound mediated transdermal drug delivery offers a promising potential for needle-less insulin delivery for diabetes treatment. Arrays of cymbal transducers have been shown to be effective in delivering therapeutic levels of insulin to decrease hyperglycemic glucose levels in rats, rabbits and pigs. To improve delivery efficiency of the cymbal arrays, an increase in the spatial intensity field without increasing the size the device or Isptp was desired. A 3 times 1 rectangular cymbal array was designed for this purpose. Rectangular cymbals maximized packing density and allowed the flexural cap resonance and the ceramic length mode resonance frequencies to be designed closer in frequency. Bringing the cap and ceramic resonances closer together increased the transmitting power and improved the electrical efficiency. By using higher order modes excited in the cap while operating at the first ceramic resonance frequency, the intensity spatial area was increased compared to the circular array. With a similar intensity (I sptp ap 50 mW/cm ), our goal was to determine if the 3 times 1 rectangular cymbal array could perform significantly better than the 3 times 3 circular array for blood glucose reduction in hyperglycemic rabbits. Nine New Zealand White rabbit (ap 4.0 kg) experiments were performed in three groups: control (n = 3) and ultrasound exposure with the 3 times 3 circular cymbal array (n = 3) or 3 times 1 rectangular cymbal array (n = 3). The rabbits were anesthetized and their thigh area was shaved for the exposure. A water tight reservoir which held the insulin was fastened between the rabbit's thigh and the ultrasound arrays. At the beginning of the experiment and every 15 minutes for 90 minutes, 0.3 ml of blood was collected from the ear vein to determine the glucose level (mg/dl) using a glucose monitoring system. For comparison between individual rabbits, the change in the blood glucose level was normalized to their initial basel

关键词： Insulin Sugar Rabbits Blood Resonance Ultrasonic imaging Ceramics Ultrasonic transducer arrays Drug delivery Resonant frequency

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Proposed Marine Mammal Noise Exposure Criteria: Current Data Base, Limitations, and research Needs

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The Journal of the Acoustical Society of America 2008年第5_SUPPLEMENT期123卷 2988-2988页

作者： Darlene R. Ketten Ann E. Bowles William T. Ellison James J. Finneran Roger L. Gentry Charles R. Greene David Kastak James H. Miller Paul E. Nachtigall W J. Richardson Brandon Southall Jeanette A. Thomas Peter Tyack Woods Hole Oceanographic Institution Applied Ocean Physics & Engineering Dept. Woods Hole MA 02543 USA dketten@whoi.edu Hubbs‐Sea World Research Institute 2595 Ingraham Street San Diego CA 92109 USA abowles@*** Marine Acoustics Inc 809 Aquidneck Ave Middletown RI 02842 USA WEMAI@*** US Navy Marine Mammal Program Space and Naval Warfare Systems Center 53560 Hull St. Code 71510 San Diego CA 92152 USA james.finneran@navy.mil ProScience Consulting LLC P.O. Box 177 Dickerson MD 20842‐0177 USA roger.gentry@*** Greeneridge Sciences Inc. 4512 Via Huerto Santa Barbara CA 93110 USA cgreene@*** UCSC Institute of Marine Sciences Long Marine Lab ‐ University of California 100 Shaffer Road Santa Cruz CA 95060 USA kastak@ucsc.edu University of Rhode Island Department of Ocean Engineering Narragansett Bay Campus Narragansett RI 02882 USA miller@egr.uri.edu University of Hawaii Hawaii Institute of Marine Biology P.O. Box 1106 Kailua HI 96734 USA nachtiga@hawaii.edu LGL Ltd. Environmental Research Associates P.O. Box 280 22 Fisher St King City AB L7B 1A6 Canada wjr@*** National Marine Fisheries Service 1315 East West Hwy SSMC III #12539 Silver Spring MD 20910‐6233 USA Brandon.Southall@noaa.gov Western Illinois University Quad Cities Department of Biological Sciences 3561 60th St. Moline IL 61265 USA j‐thomas@wiu.edu Woods Hole Oceanographic Institution Applied Ocean Physics & Engineering Dept. Woods Hole MA 02543 USA ptyack@whoi.edu

This paper presents the findings of an inter‐disciplinary expert panel based on comprehensive review of hearing and noise effects data for marine and land mammals. The principal motivation for the review was to assist formulation of data‐based noise exposure criteria in light of rapidly evolving research advances in marine mammal hearing and underwater noise effects. Levels estimated to induce permanent hearing loss were determined for single exposure events for cetaceans (in water) and pinnipeds (in air and water) for each of 15 sound type/animal group combinations. These recommendations represent a current best estimate only and are modular, with modifiable key variables; e.g., source and exposure, to facilitate revision as data improve. In some cases, relatively explicit injury limits are proposed, e.g., 186 dB re: 1μPa2‐s (frequency‐weighted sound exposure level) and 218 dB re: 1μPapeak (unweighted peak sound pressure level) for pinnipeds in water exposed to multiple sound pulses. In others, particularly for behavioural effects of multiple‐pulse and non‐pulse exposures, response severity and significance are quantitatively scored, but the data do not allow identification of specific broadly‐applicable disturbance thresholds. These findings are a current best effort and include a discussion of limitations and recommended research needed to address data gaps.

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Eliminating Nonlinear Acoustical Effects From Thermoacoustic Refrigeration Systems

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AIP Conference Proceedings 2006年第1期838卷 407-415页

作者： Steven L. Garrett Robert W. M. Smith Matthew E. Poese Penn State Graduate Program in Acoustics and Applied Research Laboratory State College PA 16804‐0030

Nonlinear acoustical effects dissipate energy that degrades thermoacoustic refrigerator performance. The largest of these effects occur in acoustic resonators and include shock formation; turbulence and boundary layer disruption; and entry/exit (minor) losses induced by changes in resonator cross‐sectional area. Effects such as these also make the creation of accurate performance models more complicated. Suppression of shock formation by intentional introduction of resonator anharmonicity has been common practice for the past two decades. Recent attempts to increase cooling power density by increasing pressure amplitudes has required reduction of turbulence and minor loss by using an new acousto‐mechanical resonator topology. The hybrid resonator still stores potential energy in the compressibility of the gaseous working fluid, but stores kinetic energy in the moving (solid) mass of the motor and piston. This talk will first present nonlinear acoustical loss measurements obtained in a “conventional” double‐Helmholtz resonator geometry (TRITON) that dissipated four kilowatts of acoustic power. We will then describe the performance of the new “bellows bounce” resonator configuration and “vibromechanical multiplier” used in the first successful implementation of this approach that created an ice cream freezer produced at Penn State for Ben & Jerry’s.

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Acoustic background noise from sailplane-mounted microphones

Acoustic background noise from sailplane-mounted microphones

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35th International Congress and Exposition on Noise Control Engineering, INTER-NOISE 2006

作者： Gabrielson, Thomas B. Willits, Steven M. Marston, Timothy M. Haering Jr., Edward A. Murray, James E. Stucky, Mark Applied Research Laboratory - Penn State P.O. Box 30 State College PA 16804 United States Graduate Program in Acoustics P.O. Box 30 State College PA 16804 United States Research Aerodynamics NASA Dryden Research Center Edwards CA 93523 United States U.S. Air Force Test Pilot School Edwards AFB 93524 United States

ISBN: (纸本)9781604231366

One of many options for monitoring acoustic events at altitude is a sailplane-mounted sensor. In an attempt to determine the limiting background noise for acoustic measurements from a sailplane, in-flight measurements were made with microphones installed in a Schempp-Hirth Standard Cirrus and a Blanik L23. Recordings were made in steady gliding flight in a stable atmosphere at speeds ranging from 45 to 80 knots. The background noise from a sailplane-mounted microphone shows three distinct regions. The first region, above 100 Hz, is sensor-influenced flow noise and the pressure spectral density is well characterized by a non-dimensional relation. The second region, from several hertz to 100 Hz, is probably the result of sampling pre-existing pressure fluctuations in the atmosphere. For these measurements made in a convectively stable atmosphere, the pressure spectral density was between 0.005 and 0.01 Pa per root hertz (48 to 54 dB with respect to 20 μPa per root hertz). The third region, below 1 Hz, is dominated by pressure fluctuations that correlate strongly with altitude variations - either natural oscillations of the glider or pilot control inputs.

关键词： Spectral density

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Utilization of the k‐space Computational Method to Design an Intracavitary Transrectal Ultrasound Phased Array Applicator for Hyperthermia Treatment of Prostate Cancer

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AIP Conference Proceedings 2006年第1期829卷 435-439页

作者： Osama M. Al‐Bataineh Christopher M. Collins Victor W. Sparrow Robert M. Keolian Nadine Barrie Smith *Department of Bioengineering The Pennsylvania State University University Park PA 16802 ¶Department of Radiology The Pennsylvania State University Hershey PA 17033 †Graduate Program in Acoustics The Pennsylvania State University University Park PA 16802 ‡Applied Research Laboratory The Pennsylvania State University University Park PA 16802

This research utilizes the k‐space computational method to design an intracavitary probe for hyperthermia treatment of prostate cancer. A three‐dimensional (3D) photographical prostate model, utilizing imaging data from the Visible Human Project®, was the basis for inhomogeneous acoustical model development. The acoustical model accounted for sound speed, density, and absorption variations. The k‐space computational method was used to simulate ultrasound wave propagation of the designed phased array through the acoustical model. To insure the uniformity and spread of the pressure in the length of the array, and the steering and focusing capability in the width of the array, the equal‐sized elements of the phased array were 1 × 14 mm. The anatomical measurements of the prostate were used to predict the final phased array specifications (4 × 20 planar array, 1.2 MHz, element size = 1 × 14 mm, array size = 56 × 20 mm). Good agreement between the exposimetry and the k‐space results was achieved. As an example, the −3 dB distances of the focal volume were differing by 9.1% in the propagation direction for k‐space prostate simulation and exposimetry results. Temperature simulations indicated that the rectal wall temperature was elevated less than 2°C during hyperthermia treatment. Steering and focusing ability of the designed probe, in both azimuth and propagation directions, were found to span the entire prostate volume with minimal grating lobes (−10 dB reduction from the main lobe) and least heat damage to the rectal wall. Evaluations of the probe included ex vivo and in vivo controlled experiments to deliver the required thermal dose to the targeted tissue. With a desired temperature plateau of 43.0°C, the MRI temperature results at the steady state were 42.9 ± 0.38°C and 43.1 ± 0.80°C for ex vivo and in vivo experiments, respectively. Unlike conventional computational methods, the k‐space method provides a powerful tool to predict pressure wavefield and temperature r

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Noninvasive Ultrasound Transdermal Insulin Delivery and Glucose Monitoring Using a Low‐Profile Cymbal Array

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AIP Conference Proceedings 2006年第1期829卷 553-557页

作者： E.‐J. Park J. Luis R. J. Meyer M. V. Pishko N. B. Smith *Department of Bioengineering The Pennsylvania State University University Park PA 16802 †Graduate Program in Acoustics The Pennsylvania State University University Park PA 16802 ‡Applied Research Laboratory The Pennsylvania State University University Park PA 16802 §Department of Chemical Engineering The Pennsylvania State University University Park PA 16802

Recent studies have shown that ultrasound mediated transdermal drug delivery offers promising results for noninvasive drug administration. The purpose of this study was to demonstrate ultrasonic transdermal insulin delivery and in vivo sensing glucose with a novel, low‐profile ultrasound array based on the cymbal transducer. As a practical device, the array composed of circular cymbal transducers was thin (< 7mm) and weighed less than 22g. Using this array on hyperglycemic rats, our previous experiments demonstrated that blood glucose would decrease by 296.7 mg/dL from 60 minutes of ultrasound exposure. With a similar intensity, our goal was to evaluate the feasibility of insulin delivery with large animals (rabbits and pigs) and noninvasively determine the glucose level of hyperglycemic rats with the array system. Ultrasound was exposed for 60 minutes at Isptp=100 mW/cm2. With the same procedure, a preliminary experiment of large animal was performed on a pig (12 kg) at Isptp=50 mW/cm2. For the control experiments in insulin delivery, the blood glucose level varied little from the initial baseline. However, for the ultrasound and insulin exposure experiment, the glucose level was found to decrease by 132.6 mg/dL in 60 minutes and continued to decrease by 208.1 mg/dL in 90 minutes. From the preliminary pig experiment, the blood glucose level decreased by 120 mg/dL in 90 minutes. To noninvasively determine the glucose level, ultrasound exposure experiments with an electrochemical glucose biosensor were performed on hyperglycemic rats. After 20 minutes ultrasound exposure, the biosensor was placed at the exposure area to determine the concentration of glucose diffused through the skin. The glucose level of rats determined by the biosensor was 408 mg/dL which was very similar to the results of conventional glucose meter reading 396.7 mg/dL. Recently, a rectangular cymbal transducer was developed to obtain a larger sonication area without an increase in array size. Prel

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Spotlights on network operations and management research in Latin America - A report on LANOMS 2005

Spotlights on network operations and management research in ...

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作者： Granville, Lisandro Zambenedetti Gaspary, Luciano Paschoal Schulze, Bruno De Souza, José Neuman Brazil Special Interest Group on Computer Networks and Distributed Systems Brazilian Computer Society Brazil Brazilian Laboratory on Computer Networks Brazil IFIP/IEEE im Brazil Graduate Program on Applied Computing Universidade do Vale do Rio dos Sinos Brazil IEEE Communications Society Japan National Lab. for Scientific Computing - LNCC Brazil Brazilian National Research Council CNPq Brazil ACM Brazil IEEE Brazil Brazilian Computing Society Brazil Federal University of Ceará Brazil

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