Generation of Acoustic-Brownian Noise in Nuclear Magnetic
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Acoustical Engineering
National Aeronautics and Space Administration Engineering is Out of This World! Acoustical Engineering NASA is developing a new rocket called the Space Launch System, or SLS. The SLS will be able to carry astronauts and materials, known as payloads. Acoustical engineers are helping to build the SLS. Sound is a vibration. A vibration is a rapid motion of an object back and forth. Hold a piece of paper up right in front of your lips. Talk or sing into the paper. What do you feel? What do you think is causing the vibration? If too much noise, or acoustical loading, is ! caused by air passing over the SLS rocket, the vehicle could be damaged by the vibration! NAME: (Continued from front) Typical Sound Levels in Decibels (dB) Experiment with the paper. 130 — Jet takeoff Does talking louder or softer change the vibration? 120 — Pain threshold 110 — Car horn 100 — Motorcycle Is the vibration affected by the pitch of your voice? (Hint: Pitch is how deep or 90 — Power lawn mower ! high the sound is.) 80 — Vacuum cleaner 70 — Street traffic —Working area on ISS (65 db) Change the angle of the paper. What 60 — Normal conversation happens? 50 — Rain 40 — Library noise Why do you think NASA hires acoustical 30 — Purring cat engineers? (Hint: Think about how loud 20 — Rustling leaves rockets are!) 10 — Breathing 0 — Hearing Threshold How do you think the noise on an airplane compares to the noise on a rocket? Hearing protection is recommended at ! 85 decibels. NASA is currently researching ways to reduce the noise made by airplanes. -
Ultrasound Induced Cavitation and Resonance Amplification Using Adaptive Feedback Control System
Master's Thesis Electrical Engineering Ultrasound induced cavitation and resonance amplification using adaptive feedback Control System Vipul. Vijigiri Taraka Rama Krishna Pamidi This thesis is presented as part of Degree of Master of Science in Electrical Engineering with Emphasis on Signal Processing Blekinge Institute of Technology (BTH) September 2014 Blekinge Institute of Technology, Sweden School of Engineering Department of Electrical Engineering (AET) Supervisor: Dr. Torbjörn Löfqvist, PhD, LTU Co- Supervisor: Dr. Örjan Johansson, PhD, LTU Shadow Supervisor/Examiner: Dr. Sven Johansson, PhD, BTH Ultrasound induced cavitation and resonance amplification using adaptive feedback Control System Master`s thesis Vipul, Taraka, 2014 Performed in Electrical Engineering, EISlab, Dep’t of Computer Science, Electrical and Space Engineering, Acoustics Lab, dep’t of Acoustics at Lulea University of Technology ii | Page This thesis is submitted to the Department of Applied signal processing at Blekinge Institute of Technology in partial fulfilment of the requirements for the degree of Master of Science in Electrical Engineering with emphasis on Signal Processing. Contact Information: Authors: Vipul Vijigiri Taraka Rama Krishna Pamidi Dept. of Applied signal processing Blekinge Institute of Technology (BTH), Sweden E-mail: [email protected],[email protected] E-mail: [email protected], [email protected] External Advisors: Dr. Torbjörn Löfqvist Department of Computer Science, Electrical and Space Engineering Internet: www.ltu.se Luleå University of technology (LTU), Sweden Phone: +46 (0)920-491777 E-mail: [email protected] Co-Advisor: Dr. Örjan Johansson Internet: www.ltu.se Department of the built environment and natural resources- Phone: +46 (0)920-491386 -Operation, maintenance and acoustics Luleå University of technology (LTU), Sweden E-mail: [email protected] University Advisor/Examiner: Dr. -
Acoustical and Optical Radiation Pressures and the Development of Single Beam Acoustical Tweezers Jean-Louis Thomas, Régis Marchiano, Diego Baresch
Acoustical and optical radiation pressures and the development of single beam acoustical tweezers Jean-Louis Thomas, Régis Marchiano, Diego Baresch To cite this version: Jean-Louis Thomas, Régis Marchiano, Diego Baresch. Acoustical and optical radiation pressures and the development of single beam acoustical tweezers. Journal of Quantitative Spectroscopy and Radiative Transfer, Elsevier, 2017, 195, pp.55-65. 10.1016/j.jqsrt.2017.01.012. hal-01438774 HAL Id: hal-01438774 https://hal.archives-ouvertes.fr/hal-01438774 Submitted on 18 Jan 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Acoustical and optical radiation pressures and the development of single beam acoustical tweezers Jean-Louis Thomasa,∗, R´egisMarchianob, Diego Barescha,b aSorbonne Universit´es,UPMC Univ Paris 06, CNRS UMR 7588, Institut des NanoSciences de Paris, 4 place Jussieu, Paris, France bSorbonne Universit´es,UPMC Univ Paris 06, CNRS UMR 7190, Institut Jean le Rond d'Alembert, 4 place Jussieu, Paris, France Abstract Studies on radiation pressure in acoustics and optics have enriched one an- other and have a long common history. Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. However, the dexter- ity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. -
Standing Waves and Sound
Standing Waves and Sound Waves are vibrations (jiggles) that move through a material Frequency: how often a piece of material in the wave moves back and forth. Waves can be longitudinal (back-and- forth motion) or transverse (up-and- down motion). When a wave is caught in between walls, it will bounce back and forth to create a standing wave, but only if its frequency is just right! Sound is a longitudinal wave that moves through air and other materials. In a sound wave the molecules jiggle back and forth, getting closer together and further apart. Work with a partner! Take turns being the “wall” (hold end steady) and the slinky mover. Making Waves with a Slinky 1. Each of you should hold one end of the slinky. Stand far enough apart that the slinky is stretched. 2. Try making a transverse wave pulse by having one partner move a slinky end up and down while the other holds their end fixed. What happens to the wave pulse when it reaches the fixed end of the slinky? Does it return upside down or the same way up? Try moving the end up and down faster: Does the wave pulse get narrower or wider? Does the wave pulse reach the other partner noticeably faster? 3. Without moving further apart, pull the slinky tighter, so it is more stretched (scrunch up some of the slinky in your hand). Make a transverse wave pulse again. Does the wave pulse reach the end faster or slower if the slinky is more stretched? 4. Try making a longitudinal wave pulse by folding some of the slinky into your hand and then letting go. -
The Standing Acoustic Wave Principle Within the Frequency Analysis Of
inee Eng ring al & ic d M e e d Misun, J Biomed Eng Med Devic 2016, 1:3 m i o c i a B l D f o e v DOI: 10.4172/2475-7586.1000116 l i a c n e r s u o Journal of Biomedical Engineering and Medical Devices J ISSN: 2475-7586 Review Article Open Access The Standing Acoustic Wave Principle within the Frequency Analysis of Acoustic Signals in the Cochlea Vojtech Misun* Department of Solid Mechanics, Mechatronics and Biomechanics, Brno University of Technology, Brno, Czech Republic Abstract The organ of hearing is responsible for the correct frequency analysis of auditory perceptions coming from the outer environment. The article deals with the principles of the analysis of auditory perceptions in the cochlea only, i.e., from the overall signal leaving the oval window to its decomposition realized by the basilar membrane. The paper presents two different methods with the function of the cochlea considered as a frequency analyzer of perceived acoustic signals. First, there is an analysis of the principle that cochlear function involves acoustic waves travelling along the basilar membrane; this concept is one that prevails in the contemporary specialist literature. Then, a new principle with the working name “the principle of standing acoustic waves in the common cavity of the scala vestibuli and scala tympani” is presented and defined in depth. According to this principle, individual structural modes of the basilar membrane are excited by continuous standing waves of acoustic pressure in the scale tympani. Keywords: Cochlea function; Acoustic signals; Frequency analysis; The following is a description of the theories in question: Travelling wave principle; Standing wave principle 1. -
Medical Image Restoration Using Optimization Techniques and Hybrid Filters
International Journal of Pure and Applied Mathematics Volume 118 No. 24 2018 ISSN: 1314-3395 (on-line version) url: http://www.acadpubl.eu/hub/ Special Issue http://www.acadpubl.eu/hub/ Medical Image Restoration Using Optimization Techniques and Hybrid Filters B.BARON SAM 1, J.SAITEJA 2, P.AKHIL 3 Assistant Professor 1 , Student 2, Student 3 School of Computing Sathyabama Institute of Science and Technology [email protected], May 26, 2018 Abstract In clinical setting, Medical pictures assumes the most huge part. Medicinal imaging brings out interior struc- tures disguised by the skin and bones, and also to analyze and treat sicknesses like malignancy, diabetic retinopathy, breaks in bones, skin maladies and so forth. The thera- peutic imaging process is distinctive for various sort of in- fections. The picture catching procedure contributes the clamor in the therapeutic picture. From now on, caught pictures should be sans clamor for legitimate conclusion of the illnesses. In this paper, we talk different clamors that influence the medicinal pictures and furthermore joined by the denoising algorithms. Computerized Image Processing innovation executes PC calculations to acknowledge advanced picture handling which suggests computerized information adjustment that enhances nature of the picture. For restorative picture data extrac- tion and encourage examination, the actualized picture han- dling calculation amplifies the lucidity and sharpness of the 1 International Journal of Pure and Applied Mathematics Special Issue picture and furthermore fascinating highlights subtle ele- ments. At first, the PC is inputted with an advanced pic- ture and modified to process the computerized picture in- formation furnished with arrangement of conditions. -
Nuclear Acoustic Resonance Investigations of the Longitudinal and Transverse Electron-Lattice Interaction in Transition Metals and Alloys V
NUCLEAR ACOUSTIC RESONANCE INVESTIGATIONS OF THE LONGITUDINAL AND TRANSVERSE ELECTRON-LATTICE INTERACTION IN TRANSITION METALS AND ALLOYS V. Müller, G. Schanz, E.-J. Unterhorst, D. Maurer To cite this version: V. Müller, G. Schanz, E.-J. Unterhorst, D. Maurer. NUCLEAR ACOUSTIC RESONANCE INVES- TIGATIONS OF THE LONGITUDINAL AND TRANSVERSE ELECTRON-LATTICE INTERAC- TION IN TRANSITION METALS AND ALLOYS. Journal de Physique Colloques, 1981, 42 (C6), pp.C6-389-C6-391. 10.1051/jphyscol:19816113. jpa-00221175 HAL Id: jpa-00221175 https://hal.archives-ouvertes.fr/jpa-00221175 Submitted on 1 Jan 1981 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. JOURNAL DE PHYSIQUE CoZZoque C6, suppZe'ment au no 22, Tome 42, de'cembre 1981 page C6-389 NUCLEAR ACOUSTIC RESONANCE INVESTIGATIONS OF THE LONGITUDINAL AND TRANSVERSE ELECTRON-LATTICE INTERACTION IN TRANSITION METALS AND ALLOYS V. Miiller, G. Schanz, E.-J. Unterhorst and D. Maurer &eie Universit8G Berlin, Fachbereich Physik, Kiinigin-Luise-Str.28-30, 0-1000 Berlin 33, Gemany Abstract.- In metals the conduction electrons contribute significantly to the acoustic-wave-induced electric-field-gradient-tensor (DEFG) at the nuclear positions. Since nuclear electric quadrupole coupling to the DEFG is sensi- tive to acoustic shear modes only, nuclear acoustic resonance (NAR) is a par- ticularly useful tool in studying the coup1 ing of electrons to shear modes without being affected by volume dilatations. -
Significance of Beating Observed in Earthquake Responses of Buildings
SIGNIFICANCE OF BEATING OBSERVED IN EARTHQUAKE RESPONSES OF BUILDINGS Mehmet Çelebi1, S. Farid Ghahari2, and Ertuğrul Taciroǧlu2 U.S. Geological Survey1 and University of California, Los Angeles2 Menlo Park, California, USA1 and Los Angeles, California, USA2 Abstract The beating phenomenon observed in the recorded responses of a tall building in Japan and another in the U.S. are examined in this paper. Beating is a periodic vibrational behavior caused by distinctive coupling between translational and torsional modes that typically have close frequencies. Beating is prominent in the prolonged resonant responses of lightly damped structures. Resonances caused by site effects also contribute to accentuating the beating effect. Spectral analyses and system identification techniques are used herein to quantify the periods and amplitudes of the beating effects from the strong motion recordings of the two buildings. Quantification of beating effects is a first step towards determining remedial actions to improve resilient building performance to strong earthquake induced shaking. Introduction In a cursory survey of several textbooks on structural dynamics, it can be seen that beating effects have not been included in their scopes. On the other hand, as more earthquake response records from instrumented buildings became available, it also became evident that the beating phenomenon is common. As modern digital equipment routinely provide recordings of prolonged responses of structures, we were prompted to visit the subject of beating, since such response characteristics may impact the instantaneous and long-term shaking performances of buildings during large or small earthquakes. The main purpose in deploying seismic instruments in buildings (and other structures) is to record their responses during seismic events to facilitate studies understanding and assessing their behavior and performances during and future strong shaking events. -
Acoustic Wave Propagation in Rivers: an Experimental Study Thomas Geay1, Ludovic Michel1,2, Sébastien Zanker2 and James Robert Rigby3 1Univ
Acoustic wave propagation in rivers: an experimental study Thomas Geay1, Ludovic Michel1,2, Sébastien Zanker2 and James Robert Rigby3 1Univ. Grenoble Alpes, CNRS, Grenoble INP, GIPSA-lab, 38000 Grenoble, France 2EDF, Division Technique Générale, 38000 Grenoble, France 5 3USDA-ARS National Sedimentation Laboratory, Oxford, Mississippi, USA Correspondence to: Thomas Geay ([email protected]) Abstract. This research has been conducted to develop the use of Passive Acoustic Monitoring (PAM) in rivers, a surrogate method for bedload monitoring. PAM consists in measuring the underwater noise naturally generated by bedload particles when impacting the river bed. Monitored bedload acoustic signals depend on bedload characteristics (e.g. grain size 10 distribution, fluxes) but are also affected by the environment in which the acoustic waves are propagated. This study focuses on the determination of propagation effects in rivers. An experimental approach has been conducted in several streams to estimate acoustic propagation laws in field conditions. It is found that acoustic waves are differently propagated according to their frequency. As reported in other studies, acoustic waves are affected by the existence of a cutoff frequency in the kHz region. This cutoff frequency is inversely proportional to the water depth: larger water depth enables a better propagation of 15 the acoustic waves at low frequency. Above the cutoff frequency, attenuation coefficients are found to increase linearly with frequency. The power of bedload sounds is more attenuated at higher frequencies than at low frequencies which means that, above the cutoff frequency, sounds of big particles are better propagated than sounds of small particles. Finally, it is observed that attenuation coefficients are variable within 2 orders of magnitude from one river to another. -
In-Situ Attenuation Corrections for Radiation Force Measurements of High Frequency Ultrasound with a Conical Target
Volume 111, Number 6, November-December 2006 Journal of Research of the National Institute of Standards and Technology [J. Res. Natl. Inst. Stand. Technol. 111, 435-442 (2006)] In-situ Attenuation Corrections for Radiation Force Measurements of High Frequency Ultrasound With a Conical Target Volume 111 Number 6 November-December 2006 Steven E. Fick Radiation force balance (RFB) measure- Key words: attenuation correction; coni- ments of time-averaged, spatially-integrat- cal target; in-situ attenuation; power meas- National Institute of Standards ed ultrasound power transmitted into a urement; radiation force balance; radiation and Technology, reflectionless water load are based on pressure; ultrasonic power; ultrasound Gaithersburg, MD 20899 measurements of the power received by power. the RFB target. When conical targets are used to intercept the output of collimated, and circularly symmetric ultrasound sources operating at frequencies above a few Dorea Ruggles megahertz, the correction for in-situ atten- uation is significant, and differs signifi- cantly from predictions for idealized cir- School of Architecture, Accepted: November 7, 2006 cumstances. Empirical attenuation correc- Program in Architectural tion factors for a 45° (half-angle) absorp- Acoustics, tive conical RFB target have been deter- Rensselaer Polytechnic Institute, mined for 24 frequencies covering the 5 Troy, NY 12180 MHz to 30 MHz range. They agree well with previously unpublished attenuation calibration factors determined in 1994 for [email protected] a similar target. Available online: http://www.nist.gov/jres 1. Introduction stances, the inertia of the target causes it to effectively integrate pulses into the corresponding steady-state Radiation pressure [1-13] has been employed in a force. -
Echo Eliminator Ceiling & Wall Panels
Echo Eliminator Ceiling & Wall Panels Echo Eliminator, or Bonded Acoustical Cotton (B.A.C.), is the most cost-effective acoustical absorbing material on the market. It is a high-performance panel manufactured from recycled cotton, and is ideal for noise control applications. Echo Eliminator can easily be installed as acoustical wall panels or hanging baffles. • No VOCs (Volatile Organic Compounds) • No formaldehyde, requires no warning labels • Fungi-, mold-, and mildew-resistant • Class A Fire Rated (Non-flammable per ASTM E-84) ACOUSTICAL SURFACES, INC. CELEBRATING 35 YEARS – SOUNDPROOFING, ACOUSTICS, NOISE & VIBRATION SPECIALISTS! ™ 952.448.5300 • 800.448.0121 • [email protected] • www.acousticalsurfaces.com Echo Eliminator APPLICATIONS Residential, commercial, industrial; schools, restaurants, classrooms, Ceiling & Wall Panels houses of worship, community centers, offices, conference rooms, music rooms, recording studios, theaters, public spaces, medical facilities, audi- toriums, arenas/stadiums, warehouses, manufacturing plants, and more. Acoustics and Expected Performance: Absorbing sound and reducing echo / reverberation can be challeng- ing. Echo Eliminator offers a high Noise Reduction Coefficient (NRC) to reduce the amount of sound within a room. One-inch thick panels are appropriate for areas wher e the main issue is understanding speech. Rooms with more mid-and-low frequency noise, or where music is present, benefit from using two-inch thick panels. SIZES & OPTIONS Standard Size: 24" x 48" (minimum quantities apply, call for details); options: 12" x 12", 24" x 24", 48" x 48", 48" x 96". Note: All sizes are nominal and subject to manufacturing tolerances that may vary +/- 1/8". Thickness/Density: 1" thick / 3 lb. per cubic foot (pcf); 1" thick/6 lb. -
Modeling Mirror Shape to Reduce Substrate Brownian Noise in Interferometric Gravitational Wave Detectors
LASER INTERFEROMETER GRAVITATIONAL WAVE OBSERVATORY - LIGO - CALIFORNIA INSTITUTE OF TECHNOLOGY MASSACHUSETTS INSTITUTE OF TECHNOLOGY 2014/03/18 Modeling mirror shape to reduce substrate Brownian Noise in interferometric gravitational wave detectors Emory Brown, Matt Abernathy, Steve Penn, Rana Adhikari, and Eric Gustafson California Institute of Technology Massachusetts Institute of Technology LIGO Project, MS 100-36 LIGO Project, NW22-295 Pasadena, CA 91125 Cambridge, MA 02139 Phone (626) 395-2129 Phone (617) 253-4824 Fax (626) 304-9834 Fax (617) 253-7014 E-mail: [email protected] E-mail: [email protected] LIGO Hanford Observatory LIGO Livingston Observatory PO Box 159 19100 LIGO Lane Richland, WA 99352 Livingston, LA 70754 Phone (509) 372-8106 Phone (225) 686-3100 Fax (509) 372-8137 Fax (225) 686-7189 E-mail: [email protected] E-mail: [email protected] http://www.ligo.caltech.edu/ Abstract This paper is a report on the effect of varying mirror shape upon Brownian noise is the test mass substrate. Using finite element analysis, it was determined that by using frustum shaped test masses with a ratio between the opposing radii of about 0.7 the frequency of the principle real eigenmodes of the test mass can be shifted into higher frequency ranges. For a fused silica test mass this shape modification could increase this value from 5951 Hz to 7210 Hz, and in a silicon test mass it would increase the value from 8491 Hz to 10262 Hz, in both cases moving the principle real eigenmode to a frequency further from LIGO bands, reducing slightly the noise seen by the detector.