WorldWideScience

Sample records for acoustically driven programmable

  1. Computational dynamics of acoustically driven microsphere systems.

    Science.gov (United States)

    Glosser, Connor; Piermarocchi, Carlo; Li, Jie; Dault, Dan; Shanker, B

    2016-01-01

    We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the microsphere system with a time-dependent integral equation solver for the acoustic field that makes use of fields represented as surface expansions in spherical harmonic basis functions. The presented approach allows us to describe the interparticle interaction induced by the field as well as the dynamics of trapping in counter-propagating acoustic pulses. The integral equation formulation leads to equations of motion for the microspheres describing the effect of nondissipative drag forces. We show (1) that the field-induced interactions between the microspheres give rise to effective dipolar interactions, with effective dipoles defined by their velocities and (2) that the dominant effect of an ultrasound pulse through a cloud of microspheres gives rise mainly to a translation of the system, though we also observe both expansion and contraction of the cloud determined by the initial system geometry.

  2. Computational dynamics of acoustically driven microsphere systems

    Science.gov (United States)

    Glosser, Connor; Piermarocchi, Carlo; Li, Jie; Dault, Dan; Shanker, B.

    2016-01-01

    We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the microsphere system with a time-dependent integral equation solver for the acoustic field that makes use of fields represented as surface expansions in spherical harmonic basis functions. The presented approach allows us to describe the interparticle interaction induced by the field as well as the dynamics of trapping in counter-propagating acoustic pulses. The integral equation formulation leads to equations of motion for the microspheres describing the effect of nondissipative drag forces. We show (1) that the field-induced interactions between the microspheres give rise to effective dipolar interactions, with effective dipoles defined by their velocities and (2) that the dominant effect of an ultrasound pulse through a cloud of microspheres gives rise mainly to a translation of the system, though we also observe both expansion and contraction of the cloud determined by the initial system geometry.

  3. Computational dynamics of acoustically driven microsphere systems.

    Science.gov (United States)

    Glosser, Connor; Piermarocchi, Carlo; Li, Jie; Dault, Dan; Shanker, B

    2016-01-01

    We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the microsphere system with a time-dependent integral equation solver for the acoustic field that makes use of fields represented as surface expansions in spherical harmonic basis functions. The presented approach allows us to describe the interparticle interaction induced by the field as well as the dynamics of trapping in counter-propagating acoustic pulses. The integral equation formulation leads to equations of motion for the microspheres describing the effect of nondissipative drag forces. We show (1) that the field-induced interactions between the microspheres give rise to effective dipolar interactions, with effective dipoles defined by their velocities and (2) that the dominant effect of an ultrasound pulse through a cloud of microspheres gives rise mainly to a translation of the system, though we also observe both expansion and contraction of the cloud determined by the initial system geometry. PMID:26871188

  4. Piezoelectric driven thermo-acoustic refrigerator

    Science.gov (United States)

    Chinn, D. G.; Nouh, M.; Aldraihem, O.; Baz, A.

    2011-03-01

    Thermoacoustic refrigeration is an emerging refrigeration technology which does not rely for in its operation on the use of any moving parts or harmful refrigerants. This technology uses acoustic waves to pump heat across a temperature gradient. The vast majority of thermoacoustic refrigerators to date have used electromagnetic loudspeakers to generate the acoustic input. In this paper, the design, construction, operation, and modeling of a piezoelectric-driven thermoacoustic refrigerator are detailed. This refrigerator demonstrates the effectiveness of piezoelectric actuation in moving 0.3 W of heat across an 18 degree C temperature difference with an input power of 7.6 W. The performance characteristics of this class of thermoacoustic-piezoelectric refrigerator are modeled using DeltaEC software and the predictions are validated experimentally. The obtained results confirm the validity of the developed model. Furthermore, the potential of piezoelectric actuation as effective means for driving thermoacoustic refrigerators is demonstrated as compared to the conventional electromagnetic loudspeakers which are heavy and require high actuation energy. The developed theoretical and experimental tools can serve as invaluable means for the design and testing of other piezoelectric driven thermoacoustic refrigerator configurations.

  5. Problem based Masters Programme in Acoustics - ten years of experience

    DEFF Research Database (Denmark)

    Nielsen, Sofus Birkedal

    2008-01-01

    The Section of Acoustics at Aalborg University in Denmark has more than 10 years of experience in offering a masters programme in Acoustics. The programme provides students with classical and modern aspects of physical acoustics, psychoacoustics and electro acoustics. Also signal processing which...

  6. Acoustic metamaterials with circular sector cavities and programmable densities.

    Science.gov (United States)

    Akl, W; Elsabbagh, A; Baz, A

    2012-10-01

    Considerable interest has been devoted to the development of various classes of acoustic metamaterials that can control the propagation of acoustical wave energy throughout fluid domains. However, all the currently exerted efforts are focused on studying passive metamaterials with fixed material properties. In this paper, the emphasis is placed on the development of a class of composite one-dimensional acoustic metamaterials with effective densities that are programmed to adapt to any prescribed pattern along the metamaterial. The proposed acoustic metamaterial is composed of a periodic arrangement of cell structures, in which each cell consists of a circular sector cavity bounded by actively controlled flexible panels to provide the capability for manipulating the overall effective dynamic density. The theoretical analysis of this class of multilayered composite active acoustic metamaterials (CAAMM) is presented and the theoretical predictions are determined for a cascading array of fluid cavities coupled to flexible piezoelectric active boundaries forming the metamaterial domain with programmable dynamic density. The stiffness of the piezoelectric boundaries is electrically manipulated to control the overall density of the individual cells utilizing the strong coupling with the fluid domain and using direct acoustic pressure feedback. The interaction between the neighboring cells of the composite metamaterial is modeled using a lumped-parameter approach. Numerical examples are presented to demonstrate the performance characteristics of the proposed CAAMM and its potential for generating prescribed spatial and spectral patterns of density variation.

  7. Knowledge-Driven Game Design by Non-Programmers

    OpenAIRE

    Exman, Iaakov; Alfia, Avinoam

    2014-01-01

    Game extension is an entertaining activity that offers an opportunity to test new design approaches by non-programmers. The real challenge is to enable this activity by means of a suitable infrastructure. We propose a knowledge-driven approach with natural game-player concepts. These concepts, found in game ontologies, include game abstractions and rules for game moves. The approach has been implemented and tested for board games. These include tic-tac-toe as a simplest example, enabling exte...

  8. Drift and ion acoustic wave driven vortices with superthermal electrons

    Energy Technology Data Exchange (ETDEWEB)

    Ali Shan, S. [Theoretical Plasma Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); National Centre For Physics (NCP), Shahdra Valley Road, QAU Campus, 44000 Islamabad (Pakistan); Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad (Pakistan); Haque, Q. [Theoretical Plasma Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); National Centre For Physics (NCP), Shahdra Valley Road, QAU Campus, 44000 Islamabad (Pakistan)

    2012-08-15

    Linear and nonlinear analysis of coupled drift and acoustic mode is presented in an inhomogeneous electron-ion plasma with {kappa}-distributed electrons. A linear dispersion relation is found which shows that the phase speed of both the drift wave and the ion acoustic wave decreases in the presence of superthermal electrons. Several limiting cases are also discussed. In the nonlinear regime, stationary solutions in the form of dipolar and monopolar vortices are obtained. It is shown that the condition for the boundedness of the solution implies that the speed of drift wave driven vortices reduces with increase in superthermality effect. Ignoring density inhomogeniety, it is investigated that the lower and upper limits on the speed of the ion acoustic driven vortices spread with the inclusion of high energy electrons. The importance of results with reference to space plasmas is also pointed out.

  9. Computational dynamics of acoustically-driven microsphere systems

    CERN Document Server

    Glosser, Connor A; Dault, Daniel L; Piermarocchi, Carlo; Shanker, Balasubramaniam

    2015-01-01

    We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the microsphere system with a time-dependent integral equation solver for the acoustic field that makes use of fields represented as surface expansions in spherical harmonic basis functions. The presented approach allows us to describe the inter-particle interaction induced by the field as well as the dynamics of trapping in counter-propagating acoustic pulses. The integral equation formulation leads to equations of motion for the microspheres describing the effect of non-dissipative drag forces. We show (1) that the field-induced interactions between the microspheres give rise to effective dipolar interactions, with effective dipoles defined by their velocities, and (2) that the dominant effect of an ultrasound pulse through a cloud of microspheres gives rise mainly to a translation ...

  10. Modeling Acoustically Driven Microbubbles by Macroscopic Discrete-Mechanical Analogues

    Directory of Open Access Journals (Sweden)

    Víctor Sánchez-Morcillo

    2013-06-01

    Full Text Available The dynamics of continuous systems that exhibit circular or spherical symmetry like drops, bubbles or some macromolecules, under the influence of some external excitation, develop surface patters that are hard to predict in most practical situations. In the particular case of acoustically driven microbubbles (ultrasound contrast agent, the study of the behavior of the bubble shell requires complex modeling even for describe the most simple oscillation patterns. Furthermore, due to the smallness of the spatio-temporal scale of the problem, an experimental approach requires expensive hardware setup. Despite the complexity of the particular physical problem, the basic dynamical features of some continuous physical systems can be captured by simple models of coupled oscillators. In this work we consider an analogy between a shelled-gas bubble cavitating under the action of an acoustic field and a discrete mechanical system. Thus, we present a theoretical and experimental study of the spatial instabilities of a circular ring of coupled pendulums parametrically driven by a vertical harmonic force. The system is capable of wave propagation and exhibit nonlinearities and dispersion, so manifest rich dynamics: normal oscillation modes (breathing, dipole, quadrupole... and localized patterns of different types (breathers and kinks witch are predicted by finite-differences numerical solutions and observed experimentally. On the basis of this analogy, the oscillation patterns and localized modes observed experimentally in acoustically driven bubbles are interpreted and discussed.

  11. 14 CFR 36.9 - Acoustical change: Propeller-driven small airplanes and propeller-driven commuter category...

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Acoustical change: Propeller-driven small airplanes and propeller-driven commuter category airplanes. 36.9 Section 36.9 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT NOISE STANDARDS: AIRCRAFT TYPE AND AIRWORTHINESS CERTIFICATION General §...

  12. SAMARUC a Programmable system for Passive acoustic monitoring of cetaceans

    OpenAIRE

    Miralles Ricós, Ramón; Lara Martínez, Guillermo-Fernan; CARRIÓN GARCÍA, ALICIA; Esteban, José Antonio

    2013-01-01

    This paper reports the work carried out by iTEAM researchers in Passive Acoustic Monitoring (PAM) for underwater monitoring of cetaceans. It includes a description of novel signal processing algorithms for detection and classification of aquatic mammal species as well as a hardware system called SAMARUC specially designed in collaboration with marine biologists. Ministerio de Ciencia e Innovación within the Project number TEC2011-23403 Miralles Ricós, R.; Lara Martínez, G.; Carrión Gar...

  13. Tunable arrayed waveguide grating driven by surface acoustic waves

    Science.gov (United States)

    Crespo-Poveda, Antonio; Hernández-Mínguez, Alberto; Biermann, Klaus; Tahraoui, Abbes; Gargallo, Bernardo; Muñoz, Pascual; Santos, Paulo V.; Cantarero, Andrés.; de Lima, Maurício M.

    2016-03-01

    We present a design approach for compact reconfigurable phased-array wavelength-division multiplexing (WDM) devices with N access waveguides (WGs) based on multimode interference (MMI) couplers. The proposed devices comprise two MMI couplers which are employed as power splitters and combiners, respectively, linked by an array of N single-mode WGs. First, passive devices are explored. Taking advantage of the transfer phases between the access ports of the MMI couplers, we derive very simple phase relations between the arms that provide wavelength dispersion at the output plane of the devices. When the effective refractive index of the WGs is modulated with the proper relative optical phase difference, each wavelength component can switch paths between the preset output channel and the remaining output WGs. Moreover, very simple phase relations between the modulated WGs that enable the reconfiguration of the output channel distribution when the appropriated coupling lengths of the MMI couplers are chosen are also derived. In this way, a very compact expression to calculate the channel assignment of the devices as a function of the applied phase shift is derived for the general case of N access WGs. Finally, the experimental results corresponding to an acoustically driven phased-array WDM device with five access WGs fabricated on (Al,Ga)As are shown.

  14. Single-electron transport driven by surface acoustic waves: Moving quantum dots versus short barriers

    DEFF Research Database (Denmark)

    Utko, Pawel; Hansen, Jørn Bindslev; Lindelof, Poul Erik;

    2007-01-01

    We have investigated the response of the acoustoelectric-current driven by a surface-acoustic wave through a quantum point contact in the closed-channel regime. Under proper conditions, the current develops plateaus at integer multiples of ef when the frequency f of the surface-acoustic wave or t...

  15. Design of acoustic logging signal source of imitation based on field programmable gate array

    Science.gov (United States)

    Zhang, K.; Ju, X. D.; Lu, J. Q.; Men, B. Y.

    2014-08-01

    An acoustic logging signal source of imitation is designed and realized, based on the Field Programmable Gate Array (FPGA), to improve the efficiency of examining and repairing acoustic logging tools during research and field application, and to inspect and verify acoustic receiving circuits and corresponding algorithms. The design of this signal source contains hardware design and software design,and the hardware design uses an FPGA as the control core. Four signals are made first by reading the Random Access Memory (RAM) data which are inside the FPGA, then dealing with the data by digital to analog conversion, amplification, smoothing and so on. Software design uses VHDL, a kind of hardware description language, to program the FPGA. Experiments illustrate that the ratio of signal to noise for the signal source is high, the waveforms are stable, and also its functions of amplitude adjustment, frequency adjustment and delay adjustment are in accord with the characteristics of real acoustic logging waveforms. These adjustments can be used to imitate influences on sonic logging received waveforms caused by many kinds of factors such as spacing and span of acoustic tools, sonic speeds of different layers and fluids, and acoustic attenuations of different cementation planes.

  16. Surface-acoustic-wave-driven luminescence from a lateral p-n junction

    Science.gov (United States)

    Gell, J. R.; Atkinson, P.; Bremner, S. P.; Sfigakis, F.; Kataoka, M.; Anderson, D.; Jones, G. A. C.; Barnes, C. H. W.; Ritchie, D. A.; Ward, M. B.; Norman, C. E.; Shields, A. J.

    2006-12-01

    The authors report surface-acoustic-wave-driven luminescence from a lateral p-n junction formed by molecular beam epitaxy regrowth of a modulation doped GaAs /AlGaAs quantum well on a patterned GaAs substrate. Surface-acoustic-wave-driven transport is demonstrated by peaks in the electrical current and light emission from the GaAs quantum well at the resonant frequency of the transducer. This type of junction offers high carrier mobility and scalability. The demonstration of surface-acoustic-wave luminescence is a significant step towards single-photon applications in quantum computation and quantum cryptography.

  17. Matching simulations with measured acoustic data from Roman Theatres using the ODEON programme

    DEFF Research Database (Denmark)

    Nielsen, Martin Lisa; Rindel, Jens Holger; Christensen, Claus Lynge;

    2005-01-01

    In the context of the ERATO research project (“identification, Evaluation and Revival of the Acoustical heritage of ancient Theatres and Odea”) funded by the European Union, acoustic measurements as well as computer simulations have been carried out in the Aspendos Theatre, Turkey and in the south...... theatre in Jerash, Jordan. The simulations are made with the ODEON software, for which a new frequency-dependent diffraction method is currently being developed for implementation in future versions of the programme. In order to make the virtual restorations of these ancient Roman theatres as correct....... The paper describes this exercise, the calculation parameters in ODEON that were adjusted in the process, and the extent to which it was successful....

  18. Open Air Laboratories (OPAL): A community-driven research programme

    Energy Technology Data Exchange (ETDEWEB)

    Davies, L., E-mail: l.davies@imperial.ac.uk [Imperial College London, London SW7 2AZ (United Kingdom); Bell, J.N.B.; Bone, J.; Head, M.; Hill, L. [Imperial College London, London SW7 2AZ (United Kingdom); Howard, C. [Natural History Museum, London SW7 5BD (United Kingdom); Hobbs, S.J. [Environment Department, University of York, Heslington, York YO10 5DD (United Kingdom); Jones, D.T. [Imperial College London, London SW7 2AZ (United Kingdom); Natural History Museum, London SW7 5BD (United Kingdom); Power, S.A. [Imperial College London, London SW7 2AZ (United Kingdom); Rose, N. [Department of Geography, University College London, London WC1E 6BT (United Kingdom); Ryder, C.; Seed, L. [Imperial College London, London SW7 2AZ (United Kingdom); Stevens, G. [Natural History Museum, London SW7 5BD (United Kingdom); Toumi, R.; Voulvoulis, N. [Imperial College London, London SW7 2AZ (United Kingdom); White, P.C.L. [Environment Department, University of York, Heslington, York YO10 5DD (United Kingdom)

    2011-08-15

    OPAL is an English national programme that takes scientists into the community to investigate environmental issues. Biological monitoring plays a pivotal role covering topics of: i) soil and earthworms; ii) air, lichens and tar spot on sycamore; iii) water and aquatic invertebrates; iv) biodiversity and hedgerows; v) climate, clouds and thermal comfort. Each survey has been developed by an inter-disciplinary team and tested by voluntary, statutory and community sectors. Data are submitted via the web and instantly mapped. Preliminary results are presented, together with a discussion on data quality and uncertainty. Communities also investigate local pollution issues, ranging from nitrogen deposition on heathlands to traffic emissions on roadside vegetation. Over 200,000 people have participated so far, including over 1000 schools and 1000 voluntary groups. Benefits include a substantial, growing database on biodiversity and habitat condition, much from previously unsampled sites particularly in urban areas, and a more engaged public. - Highlights: > Environmental research conducted jointly by the public and scientists. > Over 200,000 people involved, 8000 sites surveyed, uncertainty minimised. > New insights into urban pollution. > A more engaged and informed society. - Research is enriched where the public and scientists work together.

  19. Pulse Compression by Filamentation in Argon with an Acoustic Optical Programmable Dispersive Filter for Predispersion Compensation

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-Wei; JIANG Yong-Liang; LENG Yu-Xin; LIU Jun; GE Xiao-Chun; LI Ru-Xin; XU Zhi-Zhan

    2006-01-01

    @@ We have experimentally demonstrated pulses 0.4 mJ in duration smaller than 12 fs with an excellent spatial beam profile by self-guided propagation in argon. The original 52fs pulses from the chirped pulsed amplification laser system are first precompressed to 32 fs by inserting an acoustic optical programmable dispersive filter instrument into the laser system for spectrum reshaping and dispersion compensation, and the pulse spectrum is subsequently broadened by filamentation in an argon cell. By using chirped mirrors for post-dispersion compensation, the pulses are successfully compressed to smaller than 12fs.

  20. Solar wind driven dust acoustic instability with Lorentzian kappa distribution

    Energy Technology Data Exchange (ETDEWEB)

    Arshad, Kashif [National Center for Physics (NCP), Quaid-i-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Pakistan Institute of Engineering and Applied Sciences, P.O. Nilore, Islamabad and University of Wah, Wah Cantt 47040 (Pakistan); Ehsan, Zahida, E-mail: Ehsan.zahida@gmail.com [National Center for Physics (NCP), Quaid-i-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Universita degli Studi del Molise, 86090 Pesche - IS (Italy); INFN Sezione di Napoli, 80126 Napoli (Italy); Department of Physics, COMSATS Institute of Information Technology (CIIT), Defence Road, Off Raiwind Road, Lahore 86090 (Pakistan); Khan, S. A. [National Center for Physics (NCP), Quaid-i-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Mahmood, S. [Theoretical Plasma Physics Division, PINSTEC, PO Box Nilore, Islamabad 44000 (Pakistan)

    2014-02-15

    In a three species electron-ion-dust plasma following a generalized non-Maxwellian distribution function (Lorentzian or kappa), it is shown that a kinetic instability of dust-acoustic mode exists. The instability threshold is affected when such (quasineutral) plasma permeates through another static plasma. Such case is of interest when the solar wind is streaming through the cometary plasma in the presence of interstellar dust. In the limits of phase velocity of the waves larger and smaller than the thermal velocity of dust particles, the dispersion properties and growth rate of dust-acoustic mode are investigated analytically with validation via numerical analysis.

  1. Temporal characteristics of surface-acoustic-wave-driven luminescence from a lateral p-n junction

    Science.gov (United States)

    Gell, J. R.; Ward, M. B.; Shields, A. J.; Atkinson, P.; Bremner, S. P.; Anderson, D.; Kataoka, M.; Barnes, C. H. W.; Jones, G. A. C.; Ritchie, D. A.

    2007-07-01

    Short radio frequency pulses were used to study the surface-acoustic-wave-driven light emission from a molecular beam epitaxy regrown GaAs /AlGaAs lateral p-n junction. The luminescence provides a fast probe of the signals arriving at the junction allowing the authors to temporally separate the effect of the surface-acoustic-wave from pickup of the free space electromagnetic wave. Oscillations in the light intensity are resolved at the resonant frequency of the transducer, suggesting that the surface-acoustic-wave is transporting electrons across the junction in packets.

  2. Acoustically driven filtration of particulate suspensions in porous media

    Science.gov (United States)

    Gupta, Sanjay

    1997-12-01

    A novel method of filtration of liquid suspensions containing micron to millimeter size particles has been developed. A resonant ultrasonic field, applied across a highly porous medium, has been used to trap fine particles inside the large pores (relative to the particle size) of the medium. Three types of porous media, unconsolidated bed of 3 mm glass beads, consolidated open pore aluminum mesh, and reticulated polyester polyurethane foam were investigated as the test media. Reasonable filtration efficiencies were achieved for model aqueous suspensions of 325 mesh polystyrene particles in all three porous media. The expected trends of filtration performance with respect to suspension flow rate, its concentration, and the acoustic field intensity were confirmed. The Filtration phenomena was found to be limited by non-physical saturation of porous media. At saturation, the particles collected inside the media were found to exhibit macroscopic vibrations which allows them to escape with the carrier fluid. The highly porous POLY foam (95% porosity) was found to be the best media for suspension studied in terms of the duration of particle retention and percentage filtration efficiencies. The aluminum mesh performed slightly poorer. The unconsolidated porous media collected the least amount of solids. A simple theoretical development based on particle trajectory around an infinitely long cylindrical fiber, in the presence of acoustic field, has been initiated. In principle, the new filtration method is similar to high gravity magnetic separation but the acoustic method has a wider scope due to inherent acoustic contrast present in most suspensions. The low pressure drop, ease of operation, amenability to large scale operation and reasonable filtration efficiency make the new method highly attractive and suitable for practical applications.

  3. The dynamics of surface acoustic wave-driven scaffold cell seeding.

    NARCIS (Netherlands)

    Bok, M.H.H.; Li, H.; Yeo, L.Y.; Friend, J.R.

    2009-01-01

    Flow visualization using fluorescent microparticles and cell viability investigations are carried out to examine the mechanisms by which cells are seeded into scaffolds driven by surface acoustic waves. The former consists of observing both the external flow prior to the entry of the suspension into

  4. Using micro-3D printing to build acoustically driven microswimmers.

    Science.gov (United States)

    Bertin, Nicolas; Stephan, Olivier; Marmottant, Philippe; Spelman, Tamsin; Lauga, Eric; Dyfcom Team; Complex; Biological Fluids Team

    2015-11-01

    With no protection, a micron-sized free air bubble at room temperature in water has a life span shorter than a few tens of seconds. Using two-photon lithography, which is similar to 3D printing at the micron scale, we can build ``armors'' for these bubbles: micro-capsules with an opening to contain the bubble and extend its life to several hours in biological buffer solutions. When excited by an ultrasound transducer, a 20 μm bubble performs large amplitude oscillations in the capsule opening and generates a powerful acoustic streaming flow (velocity up to dozens of mm/s). A collaboration with the Dept. of Applied Mathematics and Theoretical Physics, University of Cambridge, is helping us predict the true resonance of these capsules and the full surrounding streaming flow. The present Bubbleboost project aims at creating red blood cell sized capsules (~ 10-20 μm) that can move on their own with a non-contact acoustic excitation for drug delivery applications. Another application of this research is in microfluidics: we are able to fabricate fields of capsules able to generate mixing effects in microchannels, or use the bubble-generated flow to guide passing objects at a junction. ERC Grant Agreement Bubbleboost no. 614655.

  5. Preliminary design of an advanced programmable digital filter network for large passive acoustic ASW systems. [Parallel processor

    Energy Technology Data Exchange (ETDEWEB)

    McWilliams, T.; Widdoes, Jr., L. C.; Wood, L.

    1976-09-30

    The design of an extremely high performance programmable digital filter of novel architecture, the LLL Programmable Digital Filter, is described. The digital filter is a high-performance multiprocessor having general purpose applicability and high programmability; it is extremely cost effective either in a uniprocessor or a multiprocessor configuration. The architecture and instruction set of the individual processor was optimized with regard to the multiple processor configuration. The optimal structure of a parallel processing system was determined for addressing the specific Navy application centering on the advanced digital filtering of passive acoustic ASW data of the type obtained from the SOSUS net. 148 figures. (RWR)

  6. Detection of steam leaks into sodium in fast reactor steam generators by acoustic techniques - An overview of Indian programme

    International Nuclear Information System (INIS)

    Realising the potential of acoustic leak detection technique, an experimental programme was initiated a few years back at Indira Gandhi Centre for Atomic Research (IGCAR) to develop this technique. The first phase of this programme consists of experiments to measure background noise characteristics on the steam generator modules of the 40 MW (thermal) Fast Breeder Test Reactor (FBTR) at Kalpakkam and experiments to establish leak noise characteristics with the help of a leak simulation set up. By subjecting the measured data from these experiments to signal analysis techniques, a criterion for acoustic leak detection for FBTR steam generator will be evolved. Second phase of this programme will be devoted to developing an acoustic leak detection system suitable for installation in the 500 MWe Prototype Fast Breeder Reactor (PFBR). This paper discusses the first phase of the experimental programme, results obtained from measurements carried out on FBTR steam generators and results obtained from leak simulation experiments. Acoustic leak detection system being considered for PFBR is also briefly described. 4 refs, 8 figs, 1 tab

  7. Coupled dynamics of translation and collapse of acoustically driven microbubbles.

    Science.gov (United States)

    Reddy, Anil J; Szeri, Andrew J

    2002-10-01

    Pressure gradients drive the motion of microbubbles relative to liquids in which they are suspended. Examples include the hydrostatic pressure due to a gravitational field, and the pressure gradients in a sound field, useful for acoustic levitation. In this paper, the equations describing the coupled dynamics of radial oscillation and translation of a microbubble are given. The formulation is based on a recently derived expression for the hydrodynamic force on a bubble of changing size in an incompressible liquid [J. Magnaudet and D. Legendre, Phys. Fluids 10, 550-556 (1998)]. The complex interaction between radial and translation dynamics is best understood by examination of the added momentum associated with the liquid motion caused by the moving bubble. Translation is maximized when the bubble collapses violently. The new theory for coupled collapse and translation dynamics is compared to past experiments and to previous theories for decoupled translation dynamics. Special attention is paid to bubbles of relevance in biomedical applications.

  8. A Requirements-Driven Optimization Method for Acoustic Treatment Design

    Science.gov (United States)

    Berton, Jeffrey J.

    2016-01-01

    Acoustic treatment designers have long been able to target specific noise sources inside turbofan engines. Facesheet porosity and cavity depth are key design variables of perforate-over-honeycomb liners that determine levels of noise suppression as well as the frequencies at which suppression occurs. Layers of these structures can be combined to create a robust attenuation spectrum that covers a wide range of frequencies. Looking to the future, rapidly-emerging additive manufacturing technologies are enabling new liners with multiple degrees of freedom, and new adaptive liners with variable impedance are showing promise. More than ever, there is greater flexibility and freedom in liner design. Subject to practical considerations, liner design variables may be manipulated to achieve a target attenuation spectrum. But characteristics of the ideal attenuation spectrum can be difficult to know. Many multidisciplinary system effects govern how engine noise sources contribute to community noise. Given a hardwall fan noise source to be suppressed, and using an analytical certification noise model to compute a community noise measure of merit, the optimal attenuation spectrum can be derived using multidisciplinary systems analysis methods. The subject of this paper is an analytical method that derives the ideal target attenuation spectrum that minimizes noise perceived by observers on the ground.

  9. A model for an acoustically driven microbubble inside a rigid tube

    KAUST Repository

    Qamar, Adnan

    2014-09-10

    A theoretical framework to model the dynamics of acoustically driven microbubble inside a rigid tube is presented. The proposed model is not a variant of the conventional Rayleigh-Plesset category of models. It is derived from the reduced Navier-Stokes equation and is coupled with the evolving flow field solution inside the tube by a similarity transformation approach. The results are computed, and compared with experiments available in literature, for the initial bubble radius of Ro=1.5μm and 2μm for the tube diameter of D=12μm and 200μm with the acoustic parameters as utilized in the experiments. Results compare quite well with the existing experimental data. When compared to our earlier basic model, better agreement on a larger tube diameter is obtained with the proposed coupled model. The model also predicts, accurately, bubble fragmentation in terms of acoustic and geometric parameters.

  10. Temporal isolation of surface-acoustic-wave-driven luminescence from a lateral p n junction using pulsed techniques

    Science.gov (United States)

    Gell, J. R.; Ward, M. B.; Atkinson, P.; Bremner, S. P.; Anderson, D.; Norman, C. E.; Kataoka, M.; Barnes, C. H. W.; Jones, G. A. C.; Shields, A. J.; Ritchie, D. A.

    2008-04-01

    The authors report surface-acoustic-wave-driven luminescence from a lateral p-n junction formed by molecular-beam epitaxy regrowth of a modulation doped GaAs/AlGaAs quantum well on a patterned GaAs substrate. Pulsed techniques are used to isolate the surface-acoustic-wave-driven emission from any emission due to pick-up of the free-space electromagnetic wave. The luminescence provides a fast probe of the signals arriving at the p-n junction allowing the response of the junction to the surface-acoustic-wave to be studied in the time domain. Oscillations in the surface-acoustic-wave-driven component of the light intensity are resolved at the resonant frequency of the transducer, suggesting that the surface-acoustic-wave is transporting electrons across the junction in packets.

  11. A multichannel acoustically driven microfluidic chip to study particle-cell interactions

    OpenAIRE

    Wang, Xue-Yan; Fillafer, Christian; Pichl, Clara; Deinhammer, Stephanie; Hofer-Warbinek, Renate; Wirth, Michael; Gabor, Franz

    2013-01-01

    Microfluidic devices have emerged as important tools for experimental physiology. They allow to study the effects of hydrodynamic flow on physiological and pathophysiological processes, e.g., in the circulatory system of the body. Such dynamic in vitro test systems are essential in order to address fundamental problems in drug delivery and targeted imaging, such as the binding of particles to cells under flow. In the present work an acoustically driven microfluidic platform is presented in wh...

  12. Acoustically-driven thread-based tuneable gradient generators.

    Science.gov (United States)

    Ramesan, Shwathy; Rezk, Amgad R; Cheng, Kai Wei; Chan, Peggy P Y; Yeo, Leslie Y

    2016-08-01

    Thread-based microfluidics offer a simple, easy to use, low-cost, disposable and biodegradable alternative to conventional microfluidic systems. While it has recently been shown that such thread networks facilitate manipulation of fluid samples including mixing, flow splitting and the formation of concentration gradients, the passive capillary transport of fluid through the thread does not allow for precise control due to the random orientation of cellulose fibres that make up the thread, nor does it permit dynamic manipulation of the flow. Here, we demonstrate the use of high frequency sound waves driven from a chip-scale device that drives rapid, precise and uniform convective transport through the thread network. In particular, we show that it is not only possible to generate a stable and continuous concentration gradient in a serial dilution and recombination network, but also one that can be dynamically tuned, which cannot be achieved solely with passive capillary transport. Additionally, we show a proof-of-concept in which such spatiotemporal gradient generation can be achieved with the entire thread network embedded in a three-dimensional hydrogel construct to more closely mimic the in vivo tissue microenvironment in microfluidic chemotaxis studies and cell culture systems, which is then employed to demonstrate the effect of such gradients on the proliferation of cells within the hydrogel. PMID:27334420

  13. Microfluidic pumping through miniaturized channels driven by ultra-high frequency surface acoustic waves

    International Nuclear Information System (INIS)

    Surface acoustic waves (SAWs) are an effective means to pump fluids through microchannel arrays within fully portable systems. The SAW-driven acoustic counterflow pumping process relies on a cascade phenomenon consisting of SAW transmission through the microchannel, SAW-driven fluid atomization, and subsequent coalescence. Here, we investigate miniaturization of device design, and study both SAW transmission through microchannels and the onset of SAW-driven atomization up to the ultra-high-frequency regime. Within the frequency range from 47.8 MHz to 754 MHz, we show that the acoustic power required to initiate SAW atomization remains constant, while transmission through microchannels is most effective when the channel widths w ≳ 10 λ, where λ is the SAW wavelength. By exploiting the enhanced SAW transmission through narrower channels at ultra-high frequencies, we discuss the relevant frequency-dependent length scales and demonstrate the scaling down of internal flow patterns and discuss their impact on device miniaturization strategies.

  14. Microfluidic pumping through miniaturized channels driven by ultra-high frequency surface acoustic waves

    Energy Technology Data Exchange (ETDEWEB)

    Shilton, Richie J., E-mail: richard.shilton@iit.it [Center for Nanotechnology Innovation @ NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, 56127 Pisa (Italy); Travagliati, Marco [Center for Nanotechnology Innovation @ NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, 56127 Pisa (Italy); NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, 56127 Pisa (Italy); Beltram, Fabio [NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, 56127 Pisa (Italy); Center for Nanotechnology Innovation @ NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, 56127 Pisa (Italy); Cecchini, Marco, E-mail: marco.cecchini@nano.cnr.it [NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, 56127 Pisa (Italy)

    2014-08-18

    Surface acoustic waves (SAWs) are an effective means to pump fluids through microchannel arrays within fully portable systems. The SAW-driven acoustic counterflow pumping process relies on a cascade phenomenon consisting of SAW transmission through the microchannel, SAW-driven fluid atomization, and subsequent coalescence. Here, we investigate miniaturization of device design, and study both SAW transmission through microchannels and the onset of SAW-driven atomization up to the ultra-high-frequency regime. Within the frequency range from 47.8 MHz to 754 MHz, we show that the acoustic power required to initiate SAW atomization remains constant, while transmission through microchannels is most effective when the channel widths w ≳ 10 λ, where λ is the SAW wavelength. By exploiting the enhanced SAW transmission through narrower channels at ultra-high frequencies, we discuss the relevant frequency-dependent length scales and demonstrate the scaling down of internal flow patterns and discuss their impact on device miniaturization strategies.

  15. Linear and quasi-linear investigation of the crossfield current-driven ion-acoustic instability

    Energy Technology Data Exchange (ETDEWEB)

    Bharuthram, R. (Natal Univ., Durban (South Africa). Plasma Physics Research Inst.; Durban-Westville Univ. (South Africa)); Hellberg, M.A. (Natal Univ., Durban (South Africa). Plasma Physics Research Inst.)

    1982-10-01

    The linear growth rate of the crossfield current-driven ion-acoustic instability is obtained for any equilibrium particle velocity distribution function of the type fsub(oj)=fsub(oj)(V/sup 2/sub(perpendicular to)),Vsub(z). Quasi-linear theory is then used to investigate the saturation of the instability. Several associated features, namely, particle diffusion in velocity space, anomalous resistivity, energy distribution and electron and ion heating rates are evaluated for a Maxwellian distribution. Finally, a brief comparison is made with the heating rates associated with the electron cyclotron drift instability.

  16. Hindas a european nuclear data programme for accelerator-driven systems

    International Nuclear Information System (INIS)

    In the HINDAS programme, nuclear data in the 20-2000 MeV range are evaluated by means of a combination of nuclear models and well-selected intermediate and high-energy experiments. A panoply of European accelerators is utilised to provide complete sets of experimental data for iron, lead and uranium over a large energy range. Nuclear model codes are being improved and validated against these new experimental data. This should result in enhanced ENDF-formatted data libraries up to 200 MeV, and cross-sections for high-energy transport codes above 200 MeV. The impact of the new data libraries and high-energy models will be directly tested on some important parameters of an accelerator-driven system (ADS). Here, we report the recent progress of the various experimental and theoretical activities in HINDAS. (author)

  17. A Comment on Interaction of Lower Hybrid Waves with the Current-Driven Ion-Acoustic Instability

    DEFF Research Database (Denmark)

    Schrittwieser, R.; Juul Rasmussen, Jens

    1985-01-01

    Majeski et al. (1984) have investigated the interaction between the current-driven 'ion-acoustic' instability and high frequency lower hybrid waves. The 'ion-acoustic' instability was excited by drawing an electron current through the plasma column of a single-ended Q-machine by means of a...... positively biased cold plate. Schmittwieser et al. do not believe that the observed instability is of the ion-acoustic type but that it is rather the so-called potential relaxation instability....

  18. Distributions of the high temperature and the high pressure inside a single acoustically driven bubble

    Institute of Scientific and Technical Information of China (English)

    YING; Chongfu(应崇福); AN; Yu(安宇)

    2002-01-01

    The physical circumstances inside an acoustically driven single gas bubble in water has been intensively explored during the past few years. Starting from the results obtained for a typical case in a well known early paper (Wu, C. C., Roberts, P. H., Phys. Rev. Lett., 1993, 70(22): 3424) and introducing successively several corrections to the physical model, this paper computes in corresponding order the temporal and spatial distributions of significant physical parameters, including the temperature and the pressure, in the bubble around the moment of the bubble's violent collapse, until expectations in consistence with the present points of view are procured. For the peak temperature our results agree with the prevailing belief that in a typical stable single bubble it is of the order of ten thousand degrees.

  19. On Nonlinear Self-interaction of Geodesic Acoustic Mode Driven By Energetic Particles

    International Nuclear Information System (INIS)

    It is shown that nonlinear self-interaction of energetic particle-driven Geodesic Acoustic Mode does not generate a second harmonic in radial electric field using the fluid model. However, kinetic effects of energetic particles can induce a second harmonic in the radial electric field. A formula for the second order plasma density perturbation is derived. It is shown that a second harmonic of plasma density perturbation is generated by the convective nonlinearity of both thermal plasma and energetic particles. Near the midplane of a tokamak, the second order plasma density perturbation (the sum of second harmonic and zero frequency sideband) is negative on the low field side with its size comparable to the main harmonic at low fluctuation level. These analytic predictions are consistent with the recent experimental observation in DIII-D.

  20. On Nonlinear Self-interaction of Geodesic Acoustic Mode Driven by Energetic Particles

    International Nuclear Information System (INIS)

    It is shown that nonlinear self-interaction of energetic particle-driven Geodesic Acoustic Mode does not generate a second harmonic in radial electric field using the fluid model. However, kinetic effects of energetic particles can induce a second harmonic in the radial electric field. A formula for the second order plasma density perturbation is derived. It is shown that a second harmonic of plasma density perturbation is generated by the convective nonlinearity of both thermal plasma and energetic particles. Near the midplane of a tokamak, the second order plasma density perturbation (the sum of second harmonic and zero frequency sideband) is negative on the low field side with its size comparable to the main harmonic at low fluctuation level. These analytic predictions are consistent with the recent experimental observation in DIII-D.

  1. Effects of dust correlations on the marginal stability of ion stream driven dust acoustic waves

    Science.gov (United States)

    Shukla, Manish K.; Avinash, K.

    2016-06-01

    The effect of dust–dust correlations on the marginal stability of dust acoustic waves excited by ion drift is studied. The ion drift is driven by the electric field {E}0 which is generally present in the discharge. Correlation effects on marginal stability are studied using augmented Debye–Hückel approximation. The marginal stability boundary is calculated in {E}0-{P}0 (P 0 is the pressure of the neutral gas) space with correlated dust grains. We show that due to dust-dust correlation the stability boundary moves into the unstable region thereby stabilizing the DAW. The effects are significant for smaller values of κ (=a/{λ }d) below unity (a is the mean particle distance and {λ }d is Debye length).

  2. Numerical simulation of 3D boundary-driven acoustic streaming in microfluidic devices.

    Science.gov (United States)

    Lei, Junjun; Hill, Martyn; Glynne-Jones, Peter

    2014-02-01

    This article discusses three-dimensional (3D) boundary-driven streaming in acoustofluidic devices. Firstly, the 3D Rayleigh streaming pattern in a microchannel is simulated and its effect on the movement of microparticles of various sizes is demonstrated. The results obtained from this model show good comparisons with 3D experimental visualisations and demonstrate the fully 3D nature of the acoustic streaming field and the associated acoustophoretic motion of microparticles in acoustofluidic devices. This method is then applied to another acoustofluidic device in order to gain insights into an unusual in-plane streaming pattern. The origin of this streaming has not been fully described and its characteristics cannot be explained from the classical theory of Rayleigh streaming. The simulated in-plane streaming pattern was in good agreement with the experimental visualisation. The mechanism behind it is shown to be related to the active sound intensity field, which supports our previous findings on the mechanism of the in-plane acoustic streaming pattern visualised and modelled in a thin-layered capillary device.

  3. A novel coupling configuration for thermoacoustically-driven pulse tube coolers: Acoustic amplifier

    Institute of Scientific and Technical Information of China (English)

    DAI Wei; LUO Ercang; HU Jianying; CHEN Yanyan

    2005-01-01

    Thermoacoustically-driven pulse tube cooler can provide cryogenic cooling power with no moving components. Up to now, pulse tube cooler is directly coupled with the thermoacoustic engine and obtainable pressure ratio for the pulse tube cooler is limited by the capability of the thermoacoustic engine. The authors propose here the concept of acoustic amplifier, which is actually a long tube connecting the engine with the pulse tube cooler. Theoretical calculation shows that suitable length and diameter of the tube can lead to a pressure wave amplification effect which means that pressure wave amplitude coming from the thermoacoustic engine can be much amplified to drive the pulse tube cooler. Based on this, a 2.8 m long copper tube with 8 mm inner diameter is used as the acoustic amplifier in experiments. The experimental results show that due to the amplification effect, pressure wave amplitude at the inlet of the pulse tube cooler is over 2.5 times of that at the engine outlet. Typically, with 1.67 kW heating power, the pressure ratio provided by the engine is 1.11 while at the inlet of the pulse tube cooler the pressure ratio is 1.32, which leads to a lowest no-load temperature of 65.7 K.

  4. Simulation study of high-frequency energetic particle driven geodesic acoustic mode

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hao, E-mail: wanghao@nifs.ac.jp; Ido, Takeshi; Osakabe, Masaki [National Institute for Fusion Science, Toki 509-5292 (Japan); Todo, Yasushi [National Institute for Fusion Science, Toki 509-5292 (Japan); The Graduate University for Advanced Studies, Toki 509-5292 (Japan)

    2015-09-15

    High-frequency energetic particle driven geodesic acoustic modes (EGAM) observed in the large helical device plasmas are investigated using a hybrid simulation code for energetic particles and magnetohydrodynamics (MHD). Energetic particle inertia is incorporated in the MHD momentum equation for the simulation where the beam ion density is comparable to the bulk plasma density. Bump-on-tail type beam ion velocity distribution created by slowing down and charge exchange is considered. It is demonstrated that EGAMs have frequencies higher than the geodesic acoustic modes and the dependence on bulk plasma temperature is weak if (1) energetic particle density is comparable to the bulk plasma density and (2) charge exchange time (τ{sub cx}) is sufficiently shorter than the slowing down time (τ{sub s}) to create a bump-on-tail type distribution. The frequency of high-frequency EGAM rises as the energetic particle pressure increases under the condition of high energetic particle pressure. The frequency also increases as the energetic particle pitch angle distribution shifts to higher transit frequency. It is found that there are two kinds of particles resonant with EGAM: (1) trapped particles and (2) passing particles with transit frequency close to the mode frequency. The EGAMs investigated in this work are destabilized primarily by the passing particles whose transit frequencies are close to the EGAM frequency.

  5. Nonlinear Evolution of the Radiation-Driven Magneto-Acoustic Instability (RMI)

    CERN Document Server

    Fernández, Rodrigo

    2012-01-01

    We examine the nonlinear development of unstable magnetosonic waves driven by a background radiative flux -- the Radiation-Driven Magneto-Acoustic Instability (RMI, a.k.a. the "photon bubble" instability). The RMI may serve as a persistent source of density, radiative flux, and magnetic field fluctuations in stably-stratified, optically-thick media. The conditions for instability are present in a variety of astrophysical environments, and do not require the radiation pressure to dominate or the magnetic field to be strong. Here we numerically study the saturation properties of the RMI, covering three orders of magnitude in the relative strength of radiation, magnetic field, and gas energies. Two-dimensional, time-dependent radiation-MHD simulations of local, stably-stratified domains are conducted with Zeus-MP in the optically-thick, highly-conducting limit. Our results confirm the theoretical expectations of Blaes and Socrates (2003) in that the RMI operates even in gas pressure-dominated environments that a...

  6. NONLINEAR EVOLUTION OF THE RADIATION-DRIVEN MAGNETO-ACOUSTIC INSTABILITY

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Rodrigo; Socrates, Aristotle [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)

    2013-04-20

    We examine the nonlinear development of unstable magnetosonic waves driven by a background radiative flux-the radiation-driven magneto-acoustic instability (RMI, a.k.a. the ''photon bubble'' instability). The RMI may serve as a persistent source of density, radiative flux, and magnetic field fluctuations in stably stratified, optically thick media. The conditions for instability are present in a variety of astrophysical environments and do not require the radiation pressure to dominate or the magnetic field to be strong. Here, we numerically study the saturation properties of the RMI, covering three orders of magnitude in the relative strength of radiation, magnetic field, and gas energies. Two-dimensional, time-dependent radiation-magnetohydrodynamic simulations of local, stably stratified domains are conducted with Zeus-MP in the optically thick, highly conducting limit. Our results confirm the theoretical expectations of Blaes and Socrates in that the RMI operates even in gas-pressure-dominated environments that are weakly magnetized. The saturation amplitude is a monotonically increasing function of the ratio of radiation to gas pressure. Keeping this ratio constant, we find that the saturation amplitude peaks when the magnetic pressure is comparable to the radiation pressure. We discuss the implications of our results for the dynamics of magnetized stellar envelopes, where the RMI should act as a source of sub-photospheric perturbations.

  7. A numerical study of microparticle acoustophoresis driven by acoustic radiation forces and streaming-induced drag forces

    DEFF Research Database (Denmark)

    Muller, Peter Barkholt; Barnkob, Rune; Jensen, Mads Jakob Herring;

    2012-01-01

    We present a numerical study of the transient acoustophoretic motion of microparticles suspended in a liquid-filled microchannel and driven by the acoustic forces arising from an imposed standing ultrasound wave: the acoustic radiation force from the scattering of sound waves on the particles...... parameters using a numerical particle-tracking scheme. The model shows the transition in the acoustophoretic particle motion from being dominated by streaming-induced drag to being dominated by radiation forces as a function of particle size, channel geometry, and material properties....

  8. Technical meeting to 'Review of national programmes on fast reactors and accelerator driven systems (ADS)'. Working material

    International Nuclear Information System (INIS)

    36th Annual Meeting of the Technical Working Group on Fast Reactors, the IAEA Technical Meeting (TM) on 'Review of National Programmes on Fast Reactors and Accelerator Driven Systems (ADS)', hosted by the Korean Atomic Energy Research Institute (KAERI) was attended by TWG-FR Members and Advisers from the following Member States (MS) and International Organizations: Brazil, France, Germany, India, Japan, the Republic of Kazakhstan, the Republic of Korea, the Russian Federation, the United Kingdom, the United States of America, and the OECD/NEA. The objectives of the meeting were to: 1) exchange information on the national programmes on Fast Reactors (FR) and Accelerator Driven Systems (ADS); 2) review the progress since the 35th TWG-FR Annual Meeting, including the status of the actions; 3) consider meeting arrangements for 2003 and 2004; 4) review the Agency's co-ordinated research activities in the field of FRs and ADS, as well as co-ordination of the TWG-FR's activities with other organizations. The participants made presentations on the status of the respective national programmes on FR and ADS development. A summary of the highlights for the period since the 35th TWG-FR Annual Meeting

  9. Investigations of Acoustics and Heat Transfer Characteristics of Thermoacoustic Driven Pulse Tube Refrigerators

    Science.gov (United States)

    Bretagne, E.; François, M.-X.; Ishikawa, H.

    2004-06-01

    The purpose of this article is to investigate the design of the ThermoAcoustic Driven Pulse Tube Refrigerator which is a promising solution for large scale pulse tube applications. Designing concepts and preliminary studies of heat transfer in heat exchangers specifically for large scale TADPTR are presented. Thus, we introduce the way to deal with different components of the Pulse Tube Refrigerator to achieve the most efficient regenerator operation with the constraints imposed by the thermoacoustic driver. The main building-concepts are illustrated by considering the combinations of a standing wave Thermoacoustic prime mover with (i) an Inertance-Orifice PTR and (ii) a Lumped Boost PTR. Both experimental and numerical results support the models. Furthermore, we investigate the heat transfer mechanism for Reynolds number between 104 to 2×105 in helium. For the current experiment, measurements are taken at the cold heat exchanger of the prime mover. For the purpose of the analysis we select testing conditions so that the particle displacement is larger than the heat exchanger length and the boundary layer assumption applies. Adequacy of the steady flow assumption is discussed. Nusselt number obtained from the measurements is then correlated with a function of Prandtl, Reynolds and Valensi numbers.

  10. Technical committee on review of national programmes on fast reactors and accelerator driven systems (ADS). Working material

    International Nuclear Information System (INIS)

    The objectives of the meeting were: to exchange information on the national programmes on fast reactors (FR) and accelerator driven systems (ADS); to review the progress since the previous IWG-FR meeting, including the status of the actions; to consider meeting arrangements for 2001 and 2002; to review the Agency co-ordinated research activities in the field of FR and ADS, as well as so-ordination of the TWG-FR activities with their organisations. This report covers the reports presented on the relevant activities in Brazil, China, France, Germany, India, Italy, Japan, Kazakhstan, Republic of Korea, Russia, Sweden, United Kingdom and USA

  11. Technical meeting to 'Review of national programmes on fast reactors and accelerator driven systems (ADS)'. Working material

    International Nuclear Information System (INIS)

    The 35th Annual Meeting of the Technical Working Group on Fast Reactors TWG-FR, previously International Working Group on Fast Reactors (IWG-FR, created in 1967), was hosted by the Forschungszentrum Karlsruhe (FZK) and was attended by TWG-FR members and advisers from the following Member States: Brazil, China, France, Germany, India, Japan, the Republic of Kazakhstan, the Republic of Korea, the Russian Federation, and the United States of America. The objectives of the meeting were: to exchange information on the national programmes on Fast Reactors (FR) and Accelerator Driven Systems (ADS); to review the progress since the 34th TWG-FR Annual Meeting, including the status of the actions; to consider meeting arrangements for 2002 and 2003; to review the Agency's co-ordinated research activities in the field of FRs and ADS, as well as co-ordination of the TWG-FR's activities with other organizations

  12. An evaluation of a Canadian peer-driven injury prevention programme for high-risk adolescents.

    Science.gov (United States)

    Tenn, L; Dewis, M E

    1996-02-01

    The mortality and morbidity resulting from serious trauma in adolescence, particularly head and spinal cord injury, constitutes a health problem of major proportions. Although many community-based prevention programmes have been reported in this last decade, few of these describe an evaluation component. In this study, a school-based prevention programme was developed by a peer group and presented by them to high-risk adolescents. The study aimed to test the efficacy of this intervention compared to the delivery of a prevention presentation to a similar group by a health care professional and compared to a control group. Measures of health locus of control, self-efficacy and behavioural intent were supplemented by open-ended items related to risk-taking behaviour change. At post-test and at 4-month follow-up, there was little evidence in the quantitative measures to support the effectiveness of the intervention for reducing injury risk factors. More encouraging findings were seen in the qualitative data. Explanations for why the intervention did not result in the expected outcomes are offered.

  13. How to develop a theory-driven evaluation design? Lessons learned from an adolescent sexual and reproductive health programme in West Africa

    Directory of Open Access Journals (Sweden)

    Dubourg Dominique

    2010-11-01

    Full Text Available Abstract Background This paper presents the development of a study design built on the principles of theory-driven evaluation. The theory-driven evaluation approach was used to evaluate an adolescent sexual and reproductive health intervention in Mali, Burkina Faso and Cameroon to improve continuity of care through the creation of networks of social and health care providers. Methods/design Based on our experience and the existing literature, we developed a six-step framework for the design of theory-driven evaluations, which we applied in the ex-post evaluation of the networking component of the intervention. The protocol was drafted with the input of the intervention designer. The programme theory, the central element of theory-driven evaluation, was constructed on the basis of semi-structured interviews with designers, implementers and beneficiaries and an analysis of the intervention's logical framework. Discussion The six-step framework proved useful as it allowed for a systematic development of the protocol. We describe the challenges at each step. We found that there is little practical guidance in the existing literature, and also a mix up of terminology of theory-driven evaluation approaches. There is a need for empirical methodological development in order to refine the tools to be used in theory driven evaluation. We conclude that ex-post evaluations of programmes can be based on such an approach if the required information on context and mechanisms is collected during the programme.

  14. A tunable acoustic metamaterial with double-negativity driven by electromagnets

    Science.gov (United States)

    Chen, Zhe; Xue, Cheng; Fan, Li; Zhang, Shu-yi; Li, Xiao-juan; Zhang, Hui; Ding, Jin

    2016-01-01

    With the advance of the research on acoustic metamaterials, the limits of passive metamaterials have been observed, which prompts the studies concerning actively tunable metamaterials with adjustable characteristic frequency bands. In this work, we present a tunable acoustic metamaterial with double-negativity composed of periodical membranes and side holes, in which the double-negativity pass band can be controlled by an external direct-current voltage. The tension and stiffness of the periodically arranged membranes are actively controlled by electromagnets producing additional stresses, and thus, the transmission and phase velocity of the metamaterial can be adjusted by the driving voltage of the electromagnets. It is demonstrated that a tiny direct-current voltage of 6V can arise a shift of double-negativity pass band by 40% bandwidth, which exhibits that it is an easily controlled and highly tunable acoustic metamaterial, and furthermore, the metamaterial marginally causes electromagnetic interference to the surroundings. PMID:27443196

  15. The Italian R and D and industrial programme for an accelerator driven system experimental plant

    International Nuclear Information System (INIS)

    Accelerator Driven Systems (ADS), coupling an accelerator with a target and a sub-critical reactor, could simultaneously burn minor actinides and transmute long-lived fission products, while producing a consistent amount of electrical energy. A team of Italian R and D organizations and industries has set up a network of coordinated programs addressed to study the design issues of an 80 MWth Experimental Facility. The present memo focalizes the attention on some results obtained by the R and D activities and by the on-going industrial short term activities aiming at the preparation of the proposed preliminary design, leaving the deal to define the details of the subsequent medium term activities to the expected common program in the European context. (author)

  16. Review of national accelerator driven system programmes for partitioning and transmutation. Proceedings of an advisory group meeting

    International Nuclear Information System (INIS)

    One of the current important issues of nuclear power is the long lived radioactive waste toxicity problem. The sharpness of this problem could be considerably reduced if, during energy production, there was the possibility to incinerate at least the most toxic radioactive isotopes (long lived fission products and minor actinides). The combination of external intensive neutron sources with facilities containing nuclear fuel, so-called hybrid systems, are under investigation in several countries. The surplus of neutrons in such systems may be used to convert most of the long lived radioactive nuclides into isotopes having a shorter lifetime. Currently, an increasing number of groups are entering this field of research. There is clearly a need for co-originated their efforts, and also for the exchange of information from nationally or internationally co-ordinated activities. Consideration of the advantages of hybrid systems, and the wide field of interdisciplinary areas of research involved, show the need for an international co-operation in this novel R and D area. The International Atomic Energy Agency has maintained an active interest in advanced nuclear technology related to accelerator driven systems (ADS), and related activities have been carried out within the framework of its programme on emerging nuclear energy systems. After thorough analyses of the outcomes of several international forums and recommendations of the IAEA Technical Committee Meeting on Feasibility and Motivation for Hybrid Concepts for Nuclear Energy Generation and Transmutation (Madrid, Spain, 1997), the IAEA conducted an Advisory Group Meeting on Review of National Accelerator Driven System Programmes in Taejon, Republic of Korea, from 1 to 4 November 1999. The scope of the meeting included review of the current R and D programmes in the Member States and the assessment of the progress in the development of hybrid concepts. The programme of the AGM included the following topics

  17. Subharmonic generation, chaos, and subharmonic resurrection in an acoustically driven fluid-filled cavity

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, John H., E-mail: john.h.cantrell@nasa.gov; Yost, William T. [NASA Langley Research Center, Research Directorate, Hampton, Virginia 23681 (United States); Adler, Laszlo [Adler Consultants, Inc./Ohio State University, Columbus, Ohio 43210 (United States)

    2015-02-15

    Traveling wave solutions of the nonlinear acoustic wave equation are obtained for the fundamental and second harmonic resonances of a fluid-filled cavity. The solutions lead to the development of a non-autonomous toy model for cavity oscillations. Application of the Melnikov method to the model equation predicts homoclinic bifurcation of the Smale horseshoe type leading to a cascade of period doublings with increasing drive displacement amplitude culminating in chaos. The threshold value of the drive displacement amplitude at tangency is obtained in terms of the acoustic drive frequency and fluid attenuation coefficient. The model prediction of subharmonic generation leading to chaos is validated from acousto-optic diffraction measurements in a water-filled cavity using a 5 MHz acoustic drive frequency and from the measured frequency spectrum in the bifurcation cascade regime. The calculated resonant threshold amplitude of 0.2 nm for tangency is consistent with values estimated for the experimental set-up. Experimental evidence for the appearance of a stable subharmonic beyond chaos is reported.

  18. Very low frequency subionospheric remote sensing of thunderstorm-driven acoustic waves in the lower ionosphere

    Science.gov (United States)

    Marshall, R. A.; Snively, J. B.

    2014-05-01

    We present observations of narrowband subionospheric VLF transmitter signals on 20 March 2001, exhibiting coherent fluctuations of over 1 dB peak to peak. Spectral analysis shows that the fluctuations have periods of 1-4min and are largely coherent. The subionospheric propagation path of the signal from Puerto Rico to Colorado passes over two regions of convective and lightning activity, as observed by GOES satellite imagery and National Lightning Detection Network lightning data. We suggest that these fluctuations are evidence of acoustic waves launched by the convective activity below, observed in the 80-90 km altitude range to which nighttime VLF subionospheric remote sensing is sensitive. These observations show that VLF subionospheric remote sensing may provide a unique, 24h remote sensing technique for acoustic and gravity wave activity. We reproduce this event in simulations using a fluid model of gravity and acoustic wave propagation to calculate the ionospheric disturbance, followed by an electromagnetic propagation model to calculate the perturbation amplitude at the location of the VLF receiver. Simulation results show that a very large and coherent convective source is required to produce these amplitude perturbations.

  19. Control of the chaotic state caused by the curent-driven ion acoustic instabilit and dynamical behavior using delayed feedback

    CERN Document Server

    Fukuyama, T; Kawai, Y; Fukuyama, Takao; Wilke, Christian; Kawai, Yoshinobu

    2004-01-01

    Controlling chaos caused by the current-driven ion acoustic instability is attempted using the delayed continuous feedback method, i.e., the time-delay auto synchronization (TDAS) method introduced by Pyragas [Phys. Lett. A 170 (1992) 421.]. When the control is applied to the typical chaotic state, chaotic orbit changes to periodic one, maintaining the instability. The chaotic state is well controlled using the TDAS method. It is found that the control is achieved when a delay time is chosen near the unstable periodic orbit corresponding to the fundamental mode. Furthermore, when the delayed feedback is applied to a periodic nonlinear regime and arbitrary time delay is chosen, the periodic state is leaded to various motions including chaos. As a related topic, the synchronization between two instabilities of autonomous discharge tubes in a glow discharge is studied. Two tubes are settled independently and interacting each other through the coupler consisted of variable resister and capacitor. When the value o...

  20. High-speed imaging of an ultrasound-driven bubble in contact with a wall: " Narcissus" effect and resolved acoustic streaming

    NARCIS (Netherlands)

    Marmottant, Philippe; Versluis, Michel; Jong, de Nico; Hilgenfeldt, Sascha; Lohse, Detlef

    2006-01-01

    We report microscopic observations of the primary flow oscillation of an acoustically driven bubble in contact with a wall, captured with the ultra high-speed camera Brandaris 128 (Chin et al. 2003). The driving frequency is up to 200 kHz, and the imaging frequency is up to 25 MHz. The details of th

  1. ANGULAR MOMENTUM TRANSPORT AND VARIABILITY IN BOUNDARY LAYERS OF ACCRETION DISKS DRIVEN BY GLOBAL ACOUSTIC MODES

    International Nuclear Information System (INIS)

    Disk accretion onto a weakly magnetized central object, e.g., a star, is inevitably accompanied by the formation of a boundary layer near the surface, in which matter slows down from the highly supersonic orbital velocity of the disk to the rotational velocity of the star. We perform high-resolution two-dimensional hydrodynamical simulations in the equatorial plane of an astrophysical boundary layer with the goal of exploring the dynamics of non-axisymmetric structures that form there. We generically find that the supersonic shear in the boundary layer excites non-axisymmetric quasi-stationary acoustic modes that are trapped between the surface of the star and a Lindblad resonance in the disk. These modes rotate in a prograde fashion, are stable for hundreds of orbital periods, and have a pattern speed that is less than and of the order of the rotational velocity at the inner edge of the disk. The origin of these intrinsically global modes is intimately related to the operation of a corotation amplifier in the system. Dissipation of acoustic modes in weak shocks provides a universal mechanism for angular momentum and mass transport even in purely hydrodynamic (i.e., non-magnetized) boundary layers. We discuss the possible implications of these trapped modes for explaining the variability seen in accreting compact objects.

  2. Mass variation of a thin liquid film driven by an acoustic wave

    International Nuclear Information System (INIS)

    In this work, we investigate the dynamics of a thin liquid film subjected to an acoustic field in its bounding vapor space. For large acoustic wavelengths, the field imposes a spatially uniform, temporally periodic temperature and pressure at the vapor side of the film interface, which leads to a periodic driving force for mass exchange with the vapor. Neglecting the dynamics of the vapor space, we adopt the “one-sided” model for evaporation/condensation of thin liquid films. In the interest of determining the effect of oscillatory mass exchange on film stability, we consider films in thermodynamic equilibrium with the mean vapor conditions. The effects of oscillatory phase change on both linear stability and nonlinear dynamics are investigated for slightly inclined ceiling films that are destabilized by gravity and subject to thermocapillary effects. At linear order, this mass exchange is not found to alter the band of unstable wave numbers and only marginally affects the growth rates. Additionally, the mass exchanged during evaporation is balanced by condensation so that the total mass of the liquid film is conserved. However, due to nonlinear effects, we find that traveling waves encouraged by the inclination are subject to net mass loss. It is then found that normal thermocapillary effects enhance this loss, and that anomalous thermocapillarity mitigates or even reverses the loss to a mass gain

  3. Randomly driven acoustic-gravity waves in the solar atmosphere: cutoff period and its observational verification

    Science.gov (United States)

    Murawski, K.; Musielak, Z. E.

    2016-09-01

    We study the propagation of acoustic-gravity waves in the solar atmosphere. The waves are excited by a space- and time-dependent random driver, whose action mimics turbulence in the upper part of the solar convection zone. Our main goal is to find vertical variations of wave periods of these waves and compare the obtained results to the recent observations of Wiśniewska et al. (2016). We solve numerically the hydrodynamic equations in the solar atmosphere whose temperature is given by the semi-empirical model of Avrett & Loeser (2008). The obtained numerical results show that wave periods vary along vertical direction in agreement with the recent observational data. We discuss physical consequences of our theoretical results.

  4. Nonlinear activity of acoustically driven gas bubble near a rigid boundary

    Energy Technology Data Exchange (ETDEWEB)

    Maksimov, Alexey [Pacific Oceanological Institute, Vladivostok 690041 (Russian Federation)

    2015-10-28

    The presence of a boundary can produce considerable changes in the oscillation amplitude of the bubble and its scattered echo. The present study fills a gap in the literature, in that it is concerned theoretically with the bubble activity at relatively small distances from the rigid boundary. It was shown that the bi-spherical coordinates provide separation of variables and are more suitable for analysis of the dynamics of these constrained bubbles. Explicit formulas have been derived which describe the dependence of the bubble emission near a rigid wall on its size and the separation distance between the bubble and the boundary. As applications, time reversal technique for gas leakage detection and radiation forces that are induced by an acoustic wave on a constrained bubble were analyzed.

  5. A portable pulmonary delivery system for nano engineered DNA vaccines driven by surface acoustic wave devices

    International Nuclear Information System (INIS)

    Full text: The increase in the need for effective delivery of potelll vaccines against infectious diseases, require robust yet straightforward pro duction of encapsulated DNA-laden aerosols. Aerosol delivery of drugs represents the next generation of vaccine delivery where the drug is deposited into the lung, which provides an ideal, non-invasive route. Moreover, several features of D A vaccines make them more attractive than conventional vaccines; thus, DNA vaccines have gained global interest for a variety of applications. However, several limitations such as ineffective cellular uptake and intracellular delivery, and degradation of DNA need to be overcome before clin ical applications. In this study, a novel and scalable engineered technique has been developed to create a biodegradable polymer system, which enables controlled delivery of a well designed DNA vaccine for immuno-therapeutics. Surface Acoustic Wave (SAW) atomisation has been found as useful mechanism for atomising fluid samples for medical and industrial devices. It is a straightforward method for synthesising un-agglomerated biodegradable nanoparti cles (<250 nm) in the absence of organic solvents which would represent a major breakthrough for biopharmaceutical encapsulation and delivery. Nano-scale polymer particles for DNA vaccines deliv ery were obtained through an evaporative process of the initial aerosol created by surface acoustic waves at 8-150 MHz, the final size of which could be controlled by modifying the initial polymer concen tration and solid contents. Thus, SAW atomiser represents a promising alternative for the development of a low power device for producing nano-engineered vaccines with a controlled and narrow size distribution as delivery system for genetic immuno-therapeutics.

  6. Masters course in Acoustics at London South Bank University - A route on to our PhD programme

    OpenAIRE

    DANCE, Stephen

    2012-01-01

    International audience The Masters program in Environmental and Architectural Acoustics (MSc) from London South Bank University is taught at the Department of Urban Engineering. This was the first Masters course at the University and has been running for more than 30 years. The MSc program is delivered on a two and five semester basis depending if taken on a full-time or part-time basis with a two semester exemption if the applicant have already been award an Institute of Acoustic Diploma....

  7. Very-Low-Frequency Subionospheric Remote Sensing of Thunderstorm-driven Acoustic and Gravity Waves in the D-region

    Science.gov (United States)

    Marshall, R. A.; Snively, J. B.

    2013-12-01

    We present observations of thunderstorm-driven perturbations to the D-region ionosphere measured by VLF subionospheric remote sensing (VLF-SRS). VLF-SRS is sensitive to electron density and collision frequency disturbances in a narrow altitude range near 85 km along the great-circle-path (GCP) between a VLF transmitter and a receiver some thousands of km away. These disturbances are measured as amplitude and/or phase perturbations to the continuous VLF transmitter signal. On March 20, 2001, a prominent event was observed by VLF receivers in Colorado monitoring the VLF transmitter in Puerto Rico, exhibiting unusually strong amplitude perturbations of up to 0.6 dB, with periods of 1-3 minutes, but no detectable phase perturbations. As these periods are well below the minimum Brunt-Vaisala period of about 5 minutes, we hypothesize that they may be associated with thunderstorm-generated acoustic waves (AWs). The GCPs from this transmitter to the receivers passed through two thunderstorms at the time of the AW event, one near the southern tip of Florida and the other over the Florida panhandle. The apparent AW event lasted for about one hour and was observed on four near-parallel GCPs separated by a few tens of km at the thunderstorm location. This data shows that VLF-SRS may provide a new, high-time-resolution (better than 1 Hz) monitoring system for acoustic and gravity waves in the upper atmosphere. To investigate the hypothesized AW source for this event, we use a two-step simulation process. A nonlinear, compressible, atmospheric dynamics model is used to simulate acoustic wave propagation from a defined source near the ground to 200 km altitude. Case studies are constructed to investigate different source configurations and perturbations to ionospheric density profiles. The modified electron and neutral density are then input to a finite-difference electromagnetic code that simulates the VLF transmitter signal propagation to the receiver over a distance of ~5000

  8. An IT R&D-programme without new code?! –State driven IT-development in Denmark

    DEFF Research Database (Denmark)

    Koch, Christian; Haugen, Tore

    2004-01-01

    The paper evaluates a public R&D programme on IT in Construction. The particular programme theory is presented. We identify the vision, the means and the awaited effects of the programmes and analyse on the background of other public development programs how this one might work. We use innovation...... the program supports the development of basic structures and guidelines in electronic tendering, classification of building data, lifecycle data management and other aspects of digital construction. Moreover a central driver in the programme is assumed to be three major professional state clients. These three...... clients of buildings cooperates with the consortia established in the programme and the assumption is that the construction sector actors will engage in developing a basis for a future legislated digital interaction with the public clients. The funding is in the same spirit limited (a total of 4 millions...

  9. An acoustically-driven biochip - Impact of flow on the cell-association of targeted drug carriers

    CERN Document Server

    Fillafer, Christian; Neumann, Jürgen; Guttenberg, Zeno; Dissauer, Silke; Lichtscheidl, Irene; Wirth, Michael; Gabor, Franz; Schneider, Matthias; 10.1039/B906006E

    2011-01-01

    The interaction of targeted drug carriers with epithelial and endothelial barriers in vivo is largely determined by the dynamics of the body fluids. To simulate these conditions in binding assays, a fully biocompatible in vitro model was developed which can accurately mimic a wide range of physiological flow conditions on a thumbnail-format cell-chip. This acoustically-driven microfluidic system was used to study the interaction characteristics of protein-coated particles with cells. Poly(D,L-lactide-co-glycolide) (PLGA) microparticles (2.86 {\\pm} 0.95 {\\mu}m) were conjugated with wheat germ agglutinin (WGA-MP, cytoadhesive protein) or bovine serum albumin (BSA-MP, nonspecific protein) and their binding to epithelial cell monolayers was investigated under stationary and flow conditions. While mean numbers of 1500 {\\pm} 307 mm-2 WGA-MP and 94 {\\pm} 64 mm-2 BSA-MP respectively were detected to be cell-bound in the stationary setup, incubation at increasing flow velocities increasingly antagonized the attachment...

  10. A laboratory acoustic emission experiment and numerical simulation of rock fracture driven by a high-pressure fluid source

    Directory of Open Access Journals (Sweden)

    Xinglin Lei

    2016-02-01

    Full Text Available In order to improve our understanding of rock fracture and fault instability driven by high-pressure fluid sources, the authors carried out rock fracture tests using granite under a confining pressure of 80 MPa with fluid injection in the laboratory. Furthermore, we tested a number of numerical models using the FLAC3D modeling software to find the best model to represent the experimental results. The high-speed multichannel acoustic emission (AE waveform recording system used in this study made it possible to examine the total fracture process through detailed monitoring of AE hypocenters and seismic velocity. The experimental results show that injecting high-pressure oil into the rock sample can induce AE activity at very low stress levels and can dramatically reduce the strength of the rock. The results of the numerical simulations show that major experimental results, including the strength, the temporal and spatial patterns of the AE events, and the role of the fluid can be represented fairly well by a model involving (1 randomly distributed defect elements to model pre-existing cracks, (2 random modification of rock properties to represent inhomogeneity introduced by different mineral grains, and (3 macroscopic inhomogeneity. Our study, which incorporates laboratory experiments and numerical simulations, indicates that such an approach is helpful in finding a better model not only for simulating experimental results but also for upscaling purposes.

  11. Digital stroboscopic holographic interferometry for power flow measurements in acoustically driven membranes

    Science.gov (United States)

    Keustermans, William; Pires, Felipe; De Greef, Daniël; Vanlanduit, Steve J. A.; Dirckx, Joris J. J.

    2016-06-01

    Despite the importance of the eardrum and the ossicles in the hearing chain, it remains an open question how acoustical energy is transmitted between them. Identifying the transmission path at different frequencies could lead to valuable information for the domain of middle ear surgery. In this work a setup for stroboscopic holography is combined with an algorithm for power flow calculations. With our method we were able to accurately locate the power sources and sinks in a membrane. The setup enabled us to make amplitude maps of the out-of-plane displacement of a vibrating rubber membrane at subsequent instances of time within the vibration period. From these, the amplitude maps of the moments of force and velocities are calculated. The magnitude and phase maps are extracted from this amplitude data, and form the input for the power flow calculations. We present the algorithm used for the measurements and for the power flow calculations. Finite element models of a circular plate with a local energy source and sink allowed us to test and optimize this algorithm in a controlled way and without the present of noise, but will not be discussed below. At the setup an earphone was connected with a thin tube which was placed very close to the membrane so that sound impinges locally on the membrane, hereby acting as a local energy source. The energy sink was a little piece of foam carefully placed against the membrane. The laser pulses are fired at selected instants within the vibration period using a 30 mW HeNe continuous wave laser (red light, 632.8 nm) in combination with an acousto-optic modulator. A function generator controls the phase of these illumination pulses and the holograms are recorded using a CCD camera. We present the magnitude and phase maps as well as the power flow measurements on the rubber membrane. Calculation of the divergence of this power flow map provides a simple and fast way of identifying and locating an energy source or sink. In conclusion

  12. Analysis Grid for Environments Linked to Obesity (ANGELO) framework to develop community-driven health programmes in an Indigenous community in Canada.

    Science.gov (United States)

    Willows, Noreen; Dyck Fehderau, David; Raine, Kim D

    2016-09-01

    Indigenous First Nations people in Canada have high chronic disease morbidity resulting in part from enduring social inequities and colonialism. Obesity prevention strategies developed by and for First Nations people are crucial to improving the health status of this group. The research objective was to develop community-relevant strategies to address childhood obesity in a First Nations community. Strategies were derived from an action-based workshop based on the Analysis Grid for Environments Linked to Obesity (ANGELO) framework. Thirteen community members with wide-ranging community representation took part in the workshop. They combined personal knowledge and experience with community-specific and national research to dissect the broad array of environmental factors that influenced childhood obesity in their community. They then developed community-specific action plans focusing on healthy eating and physical activity for children and their families. Actions included increasing awareness of children's health issues among the local population and community leadership, promoting nutrition and physical activity at school, and improving recreation opportunities. Strengthening children's connection to their culture was considered paramount to improving their well-being; thus, workshop participants developed programmes that included elders as teachers and reinforced families' acquaintance with First Nations foods and activities. The research demonstrated that the ANGELO framework is a participatory way to develop community-driven health programmes. It also demonstrated that First Nations people involved in the creation of solutions to health issues in their communities may focus on decolonising approaches such as strengthening their connection to indigenous culture and traditions. External funds were not available to implement programmes and there was no formal follow-up to determine if community members implemented programmes. Future research needs to examine the

  13. From Architectural Acoustics to Acoustical Architecture Using Computer Simulation

    OpenAIRE

    Schmidt, Anne Marie Due; KIRKEGAARD, Poul Henning

    2005-01-01

    Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to inve...

  14. A surface acoustic wave-driven micropump for particle uptake investigation under physiological flow conditions in very small volumes

    Directory of Open Access Journals (Sweden)

    Florian G. Strobl

    2015-02-01

    Full Text Available Static conditions represent an important shortcoming of many in vitro experiments on the cellular uptake of nanoparticles. Here, we present a versatile microfluidic device based on acoustic streaming induced by surface acoustic waves (SAWs. The device offers a convenient method for introducing fluid motion in standard cell culture chambers and for mimicking capillary blood flow. We show that shear rates over the whole physiological range in sample volumes as small as 200 μL can be achieved. A precise characterization method for the induced flow profile is presented and the influence of flow on the uptake of Pt-decorated CeO2 particles by endothelial cells (HMEC-1 is demonstrated. Under physiological flow conditions the particle uptake rates for this system are significantly lower than at low shear conditions. This underlines the vital importance of the fluidic environment for cellular uptake mechanisms.

  15. Can diving-induced tissue nitrogen supersaturation increase the chance of acoustically driven bubble growth in marine mammals?

    Science.gov (United States)

    Houser, D S; Howard, R; Ridgway, S

    2001-11-21

    The potential for acoustically mediated causes of stranding in cetaceans (whales and dolphins) is of increasing concern given recent stranding events associated with anthropogenic acoustic activity. We examine a potentially debilitating non-auditory mechanism called rectified diffusion. Rectified diffusion causes gas bubble growth, which in an insonified animal may produce emboli, tissue separation and high, localized pressure in nervous tissue. Using the results of a dolphin dive study and a model of rectified diffusion for low-frequency exposure, we demonstrate that the diving behavior of cetaceans prior to an intense acoustic exposure may increase the chance of rectified diffusion. Specifically, deep diving and slow ascent/descent speed contributes to increased gas-tissue saturation, a condition that amplifies the likelihood of rectified diffusion. The depth of lung collapse limits nitrogen uptake per dive and the surface interval duration influences the amount of nitrogen washout from tissues between dives. Model results suggest that low-frequency rectified diffusion models need to be advanced, that the diving behavior of marine mammals of concern needs to be investigated to identify at-risk animals, and that more intensive studies of gas dynamics within diving marine mammals should be undertaken.

  16. From Architectural Acoustics to Acoustical Architecture Using Computer Simulation

    DEFF Research Database (Denmark)

    Schmidt, Anne Marie Due; Kirkegaard, Poul Henning

    2005-01-01

    Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic...... properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to investigate the field of application that an acoustic simulation programme can have during an architectural...... acoustic design process and to set up a strategy to develop future programmes. The emphasis is put on the first three out of four phases in the working process of the architect and a case study is carried out in which each phase is represented by typical results ? as exemplified with reference...

  17. Technical meeting (TM) to 'Review of national programmes on fast reactors and accelerator driven systems (ADS)'. Technical Working Group on Fast Reactors (TWG-FR) (37th annual meeting). Working material

    International Nuclear Information System (INIS)

    The objectives of the 37th Annual Meeting of the Technical Working Group on Fast Reactors, were to: 1) exchange information on the national programmes on Fast Reactors (FR) and Accelerator Driven Systems (ADS); 2) review the progress since the 36th TWG-FR Annual Meeting, including the status of the actions; 3) consider meeting arrangements for 2004 and 2005; 4) review the Agency's co-ordinated research activities in the field of FRs and ADS, as well as co-ordination of the TWG-FR's activities with other organizations. The participants made presentations on the status of the respective national programmes on FR and ADS development. A summary of the highlights for the period since the 36th TWG-FR Annual Meeting is included in this proceedings. Annex IV contains the Review of National Programs on Fast Reactors and Accelerator Driven Systems (ADS), and the TWG-FR Activity Report for the Period May 2003-April 2004

  18. Current-driven ion-acoustic and potential-relaxation instabilities excited in plasma plume during electron beam welding

    Energy Technology Data Exchange (ETDEWEB)

    Trushnikov, D. N., E-mail: trdimitr@yandex.ru [The department for Applied Physics, Perm National Research Polytechnic University, Perm, 614990 (Russian Federation); Mladenov, G. M., E-mail: gmmladenov@abv.bg; Koleva, E. G., E-mail: eligeorg@abv.bg [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shose, 1784, Sofia (Bulgaria); Technology Centre of Electron Beam and Plasma Technologies and Techniques, 68-70 Vrania, ap.10, Banishora,1309, Sofia (Bulgaria); Belenkiy, V. Ya., E-mail: mtf@pstu.ru; Varushkin, S. V., E-mail: stepan.varushkin@mail.ru [The department for Welding Production and Technology of Constructional Materials, Perm National Research Polytechnic University, Perm, 614990 (Russian Federation)

    2014-04-15

    Many papers have sought correlations between the parameters of secondary particles generated above the beam/work piece interaction zone, dynamics of processes in the keyhole, and technological processes. Low- and high-frequency oscillations of the current, collected by plasma have been observed above the welding zone during electron beam welding. Low-frequency oscillations of secondary signals are related to capillary instabilities of the keyhole, however; the physical mechanisms responsible for the high-frequency oscillations (>10 kHz) of the collected current are not fully understood. This paper shows that peak frequencies in the spectra of the collected high-frequency signal are dependent on the reciprocal distance between the welding zone and collector electrode. From the relationship between current harmonics frequency and distance of the collector/welding zone, it can be estimated that the draft velocity of electrons or phase velocity of excited waves is about 1600 m/s. The dispersion relation with the properties of ion-acoustic waves is related to electron temperature 10 000 K, ion temperature 2 400 K and plasma density 10{sup 16} m{sup −3}, which is analogues to the parameters of potential-relaxation instabilities, observed in similar conditions. The estimated critical density of the transported current for creating the anomalous resistance state of plasma is of the order of 3 A·m{sup −2}, i.e. 8 mA for a 3–10 cm{sup 2} collector electrode. Thus, it is assumed that the observed high-frequency oscillations of the current collected by the positive collector electrode are caused by relaxation processes in the plasma plume above the welding zone, and not a direct demonstration of oscillations in the keyhole.

  19. Acoustic cryocooler

    Science.gov (United States)

    Swift, Gregory W.; Martin, Richard A.; Radenbaugh, Ray

    1990-01-01

    An acoustic cryocooler with no moving parts is formed from a thermoacoustic driver (TAD) driving a pulse tube refrigerator (PTR) through a standing wave tube. Thermoacoustic elements in the TAD are spaced apart a distance effective to accommodate the increased thermal penetration length arising from the relatively low TAD operating frequency in the range of 15-60 Hz. At these low operating frequencies, a long tube is required to support the standing wave. The tube may be coiled to reduce the overall length of the cryocooler. One or two PTR's are located on the standing wave tube adjacent antinodes in the standing wave to be driven by the standing wave pressure oscillations. It is predicted that a heat input of 1000 W at 1000 K will maintian a cooling load of 5 W at 80 K.

  20. On architectural acoustic design using computer simulation

    DEFF Research Database (Denmark)

    Schmidt, Anne Marie Due; Kirkegaard, Poul Henning

    2004-01-01

    Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic...... properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to investigate the field of application that an acoustic simulation programme can have during an architectural...... acoustic design process. The emphasis is put on the first three out of five phases in the working process of the architect and a case study is carried out in which each phase is represented by typical results ? as exemplified with reference to the design of Bagsværd Church by Jørn Utzon. The paper...

  1. Construction of reservoir flow models using deterministic and stochastic methods and driven by seismic acoustic impedance--a Gulf of Mexico example

    Energy Technology Data Exchange (ETDEWEB)

    Meanley, E.; Guderjahn, C.; Litvak, M. [BP Exploration, Houston, TX (United States)] [and others

    1995-08-01

    Rapid and accurate subsurface descriptions and flow predictions contribute to profitable field development, particularly for deep water fields of modest size. This paper shows how 3-D seismic acoustic impedance played an essential roll in that process. This Tertiary field example exhibits a classic Gulf of Mexico {open_quotes}bright{close_quotes} seismic response. The slope channel deposits yielded reflections from stacked pay zones that were often interfering vertically and laterally variable. Seismic acoustic impedance inversion for volume estimation, well placement and flow model construction. Flow model construction was facilitated using Stratamodel, where reservoir boundaries, porosity and permeability were estimated from seismic acoustic impedance. This provided a {open_quotes}deterministic{close_quotes} flow model with which well choices and development economics were explored. Alternate flow models were developed in which the effect of fine scale (sub-seismic) heterogeneities were investigated. A 3-D {open_quotes}stochastic{close_quotes} model was developed that honored geostatistical parameters as well as seismic acoustic impedance. This gave insight to permeability distributions and confirmed that connectivity between scattered sand bodies would not significantly degrade the field performance predicted by deterministic models.

  2. ADS National Programmes: China

    International Nuclear Information System (INIS)

    In China the conceptual study of an ADS concept which lasted for about five years ended in 1999. As one project of the National Basic Research Programme of China (973 Programme) in energy domain, which is sponsored by the China Ministry of Science and Technology (MOST), a five year programme of fundamental research of ADS physics and related technology was launched in 2000 and passed national review at the end of 2005. From 2007, another five year 973 Programme Key Technology Research of Accelerator Driven Subcritical System for Nuclear waste Transmutation started. The research activities were focused on HPPA physics and technology, reactor physics of external source driven subcritical assembly, nuclear data base and material study. For HPPA, a high current injector consisting of an ECR ion source, LEBT and an RFQ accelerating structure of 3.5 MeV has been built and were being improved. In reactor physics study, a series of neutron multiplication experimental study has been carrying out. The VENUS I facility has been constructed as the basic experimental platform for neutronics study in ADS blanket. VENUS I a zero power subcritical neutron multiplying assembly driven by external neutron produced by a pulsed neutron generator or 252Cf neutron source. The theoretical, experimental and simulation studies on nuclear data, material properties and nuclear fuel circulation related to ADS are carried out in order to provide the database for ADS system analysis. China Institute of Atomic Energy (CIAE), Institute of High Energy Physics (IHEP) and other Chinese institutes carried out the MOST project together. Besides CIAE, China Academy of Science (CAS) pays more and more attention to Advanced Nuclear Fuel Cycles (ANFC). A large programme of ANFC, including ADS and Th based nuclear fuel cycle, has been launched by CAS

  3. ADS National Programmes: France

    International Nuclear Information System (INIS)

    Studies related to nuclear reactors and radioactive waste started at the French National Centre for Scientific research, CNRS, as a result of the French law on radioactive waste that was published in 1991. They were initially organized around the programme PACE (Physique pour l’Aval du Cycle Electronucléaire = physics of the back end of the nuclear fuel cycle), which became PACEN (Physique pour l’Aval du Cycle et production d’Energie Nucléaire = Physics of the back end of the nuclear fuel cycle and production of nuclear energy) in 2006. Research on accelerator driven systems was from the beginning part of this programme. This research is mainly funded by the National Institute for Nuclear end Particle Physics (IN2P3) of CNRS and within the EURATOM European programmes (FP5, 6 and 7). The programme took place in several stages, and covered various scientific fields, benefitting from expertise of CNRS in the field. More specifically, it aimed and still aims to: – Test and verify the feasibility and design of the ADS concept, in terms of neutronics, physics of materials, design of the accelerator and tests of its prototypical components that have been built (or are at present under construction); – Measure and-or improve nuclear data related to radioactive waste transmutation. Today, most of the activities in support to ADS development carried out by CNRS focus on accelerator developments, GUINEVERE (Generator of Uninterrupted Intense NEutron at the lead VEnus REactor) experiment, ADS core studies, deployment scenarios and nuclear data measurements. The CEA R&D programmes on ADS are mainly focused on the European project EUROTRANS of the 6th Framework programme (2005–2010) and continued in the FREYA project of the 7th Framework Programme

  4. Communication Acoustics

    DEFF Research Database (Denmark)

    Blauert, Jens

    Communication Acoustics deals with the fundamentals of those areas of acoustics which are related to modern communication technologies. Due to the advent of digital signal processing and recording in acoustics, these areas have enjoyed an enormous upswing during the last 4 decades. The book...... the book a source of valuable information for those who want to improve or refresh their knowledge in the field of communication acoustics - and to work their way deeper into it. Due to its interdisciplinary character Communication Acoustics is bound to attract readers from many different areas, such as......: acoustics, cognitive science, speech science, and communication technology....

  5. Acoustic Neuroma

    Science.gov (United States)

    An acoustic neuroma is a benign tumor that develops on the nerve that connects the ear to the brain. ... can press against the brain, becoming life-threatening. Acoustic neuroma can be difficult to diagnose, because the ...

  6. An acoustically driven microliter flow chamber on a chip (muFCC) for cell-cell and cell-surface interaction studies.

    Science.gov (United States)

    Schneider, Matthias F; Guttenberg, Zeno; Schneider, Stefan W; Sritharan, Kumudesh; Myles, Vanessa M; Pamukci, Umut; Wixforth, Achim

    2008-03-14

    A novel method for pumping very small volumes of liquid by using surface acoustic waves is employed to create a microfluidic flow chamber on a chip. It holds a volume of only a few mul and its planar design provides complete architectural freedom. This allows for the reconstruction of even complex flow scenarios (e.g. curvatures, bifurcations and stenosis). Addition of polymer walls to the planar fluidic track enables cell culturing on the chip surface and the investigation of cell-cell adhesion dynamics under flow. We demonstrate the flexibility of the system for application in many areas of microfluidic investigations including blood clotting phenomena under various flow conditions and the investigation of different stages of cell adhesion. PMID:18306189

  7. Monitoring programme

    International Nuclear Information System (INIS)

    Her Majesty's Inspectorate of Pollution's 1992 report on its programme of monitoring radioactive substances is presented. Site operators' returns are verified and the report provides independent data on the environmental impact of authorized disposal of radioactive wastes. Radiation doses which may have been received by members of the public, fall well below the International Commission for Radiological Protection's (ICRP) recommended annual doses. (UK)

  8. Acoustical Imaging

    CERN Document Server

    Litniewski, Jerzy; Kujawska, Tamara; 31st International Symposium on Acoustical Imaging

    2012-01-01

    The International Symposium on Acoustical Imaging is a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. This interdisciplinary Symposium has been taking place continuously since 1968. In the course of the years the proceedings volumes in the Acoustical Imaging Series have become a reference for cutting-edge research in the field. In 2011 the 31st International Symposium on Acoustical Imaging was held in Warsaw, Poland, April 10-13. Offering both a broad perspective on the state-of-the-art as well as  in-depth research contributions by the specialists in the field, this Volume 31 in the Series contains an excellent collection of papers in six major categories: Biological and Medical Imaging Physics and Mathematics of Acoustical Imaging Acoustic Microscopy Transducers and Arrays Nondestructive Evaluation and Industrial Applications Underwater Imaging

  9. Acoustic textiles

    CERN Document Server

    Nayak, Rajkishore

    2016-01-01

    This book highlights the manufacturing and applications of acoustic textiles in various industries. It also includes examples from different industries in which acoustic textiles can be used to absorb noise and help reduce the impact of noise at the workplace. Given the importance of noise reduction in the working environment in several industries, the book offers a valuable guide for companies, educators and researchers involved with acoustic materials.

  10. ADS National Programmes: Belgium

    International Nuclear Information System (INIS)

    The Belgian activities in the field of Accelerator Driven Systems (ADS) are mainly related to the MYRRHA project development. MYRRHA is an accelerator driven, multi purpose fast neutron spectrum facility for R&D, cooled by a lead-bismuth eutectic. SCK•CEN has started the MYRRHA project as a national programme with several national & international bilateral collaboration agreements; the project has now evolved as an European integrated project in the frame of the IPEUROTRANS (European Commission, Sixth Framework Programme). The MYRRHA ‘Draft-2’ predesign file (completed in the early 2005) has been proposed to the partners as a basis for the XT-ADS machine. After a detailed investigation of potential alternatives, the MYRRHA concept (for the subcritical core, the primary coolant system, the accommodation of experimental rigs, the reactor vessel and the spallation target) has been kept with some modifications to achieve the XT-ADS objectives. The most recent version of the XT-ADS design was presented in the 2007 TWG meeting

  11. Programmable Oscillator

    Science.gov (United States)

    Quirk, Kevin J.; Patawaran, Ferze D.; Nguyen, Danh H.; Lee, Clement G.; Nguyen, Huy

    2011-01-01

    A programmable oscillator is a frequency synthesizer with an output phase that tracks an arbitrary function. An offset, phase-locked loop circuit is used in combination with an error control feedback loop to precisely control the output phase of the oscillator. To down-convert the received signal, several stages of mixing may be employed with the compensation for the time-base distortion of the carrier occurring at any one of those stages. In the Goldstone Solar System Radar (GSSR), the compensation occurs in the mixing from an intermediate frequency (IF), whose value is dependent on the station and band, to a common IF used in the final stage of down-conversion to baseband. The programmable oscillator (PO) is used in the final stage of down-conversion to generate the IF, along with a time-varying phase component that matches the time-base distortion of the carrier, thus removing it from the final down-converted signal.

  12. Seismo-acoustic evidence for an avalanche driven phreatic eruption through a beheaded hydrothermal system: An example from the 2012 Tongariro eruption

    Science.gov (United States)

    Jolly, A.D.; Jousset, P.; Lyons, J.J.; Carniel, R.; Fournier, R.; Fry, B.; Miller, C.

    2016-01-01

    The 6 August 2012 Te Maari eruption comprises a complex eruption sequence including multiple eruption pulses, a debris avalanche that propagated ~ 2 km from the vent, and the formation of a 500 m long, arcuate chasm, located ~ 300 m from the main eruption vent. The eruption included 6 distinct impulses that were coherent across a local infrasound network marking the eruption onset at 11:52:18 (all times UTC). An eruption energy release of ~ 3 × 1012 J was calculated using a body wave equation for radiated seismic energy. A similar calculation based on the infrasound record, shows that ~ 90% of the acoustic energy was released from three impulses at onset times 11:52:20 (~ 20% of total eruption energy), 11:52:27 (~ 50%), and 11:52:31 (~ 20%). These energy impulses may coincide with eyewitness accounts describing an initial eastward directed blast, followed by a westward directed blast, and a final vertical blast. Pre-eruption seismic activity includes numerous small unlocatable micro-earthquakes that began at 11:46:50. Two larger high frequency earthquakes were recorded at 11:49:06 and 11:49:21 followed directly by a third earthquake at 11:50:17. The first event was located within the scarp based on an arrival time location from good first P arrival times and probably represents the onset of the debris avalanche. The third event was a tornillo, characterised by a 0.8 Hz single frequency resonance, and has a resonator attenuation factor of Q ~ 40, consistent with a bubbly fluid filled resonator. This contrasts with a similar tornillo event occurring 2.5 weeks earlier having Q ~ 250–1000, consistent with a dusty gas charged resonator. We surmise from pre-eruption seismicity, and the observed attenuation change, that the debris avalanche resulted from the influx of fluids into the hydrothermal system, causing destabilisation and failure. The beheaded hydrothermal system may have then caused depressurisation frothing of the remaining gas charged system leading to the

  13. Technology Programme

    Energy Technology Data Exchange (ETDEWEB)

    Batistoni, Paola; De Marco, Francesco; Pieroni, Leonardo (ed.)

    2005-07-01

    The technology activities carried out by the Euratom-ENEA Association in the framework of the European Fusion Development Agreement concern the Next Step (International Thermonuclear Experimental Reactor - ITER), the Long-Term Programme (breeder blanket, materials, International Fusion Materials Irradiation Facility - IFMIF), Power Plant Conceptual Studies and Socio-Economic Studies. The Underlying Technology Programme was set up to complement the fusion activities as well to develop technologies with a wider range of interest. The Technology Programme mainly involves staff from the Frascati laboratories of the Fusion Technical and Scientific Unit and from the Brasimone laboratories of the Advanced Physics Technologies Unit. Other ENEA units also provide valuable contributions to the programme. ENEA is heavily engaged in component development/testing and in design and safety activities for the European Fusion Technology Programme. Although the work documented in the following covers a large range of topics that differ considerably because they concern the development of extremely complex systems, the high level of integration and coordination ensures the capability to cover the fusion system as a whole. In 2004 the most significant testing activities concerned the ITER primary beryllium-coated first wall. In the field of high-heat-flux components, an important achievement was the qualification of the process for depositing a copper liner on carbon fibre composite (CFC) hollow tiles. This new process, pre-brazed casting (PBC), allows the hot radial pressing (HRP) joining procedure to be used also for CFC-based armour monoblock divertor components. The PBC and HRP processes are candidates for the construction of the ITER divertor. In the materials field an important milestone was the commissioning of a new facility for chemical vapour infiltration/deposition, used for optimising silicon carbide composite (SiCf/SiC) components. Eight patents were deposited during 2004

  14. Radiation acoustics

    CERN Document Server

    Lyamshev, Leonid M

    2004-01-01

    Radiation acoustics is a developing field lying at the intersection of acoustics, high-energy physics, nuclear physics, and condensed matter physics. Radiation Acoustics is among the first books to address this promising field of study, and the first to collect all of the most significant results achieved since research in this area began in earnest in the 1970s.The book begins by reviewing the data on elementary particles, absorption of penetrating radiation in a substance, and the mechanisms of acoustic radiation excitation. The next seven chapters present a theoretical treatment of thermoradiation sound generation in condensed media under the action of modulated penetrating radiation and radiation pulses. The author explores particular features of the acoustic fields of moving thermoradiation sound sources, sound excitation by single high-energy particles, and the efficiency and optimal conditions of thermoradiation sound generation. Experimental results follow the theoretical discussions, and these clearl...

  15. Room Acoustics

    Science.gov (United States)

    Kuttruff, Heinrich; Mommertz, Eckard

    The traditional task of room acoustics is to create or formulate conditions which ensure the best possible propagation of sound in a room from a sound source to a listener. Thus, objects of room acoustics are in particular assembly halls of all kinds, such as auditoria and lecture halls, conference rooms, theaters, concert halls or churches. Already at this point, it has to be pointed out that these conditions essentially depend on the question if speech or music should be transmitted; in the first case, the criterion for transmission quality is good speech intelligibility, in the other case, however, the success of room-acoustical efforts depends on other factors that cannot be quantified that easily, not least it also depends on the hearing habits of the listeners. In any case, absolutely "good acoustics" of a room do not exist.

  16. Acoustical Imaging

    CERN Document Server

    Akiyama, Iwaki

    2009-01-01

    The 29th International Symposium on Acoustical Imaging was held in Shonan Village, Kanagawa, Japan, April 15-18, 2007. This interdisciplinary Symposium has been taking place every two years since 1968 and forms a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. In the course of the years the volumes in the Acoustical Imaging Series have developed and become well-known and appreciated reference works. Offering both a broad perspective on the state-of-the-art in the field as well as an in-depth look at its leading edge research, this Volume 29 in the Series contains again an excellent collection of seventy papers presented in nine major categories: Strain Imaging Biological and Medical Applications Acoustic Microscopy Non-Destructive Evaluation and Industrial Applications Components and Systems Geophysics and Underwater Imaging Physics and Mathematics Medical Image Analysis FDTD method and Other Numerical Simulations Audience Researcher...

  17. Battlefield acoustics

    CERN Document Server

    Damarla, Thyagaraju

    2015-01-01

    This book presents all aspects of situational awareness in a battlefield using acoustic signals. It starts by presenting the science behind understanding and interpretation of sound signals. The book then goes on to provide various signal processing techniques used in acoustics to find the direction of sound source, localize gunfire, track vehicles, and detect people. The necessary mathematical background and various classification and fusion techniques are presented. The book contains majority of the things one would need to process acoustic signals for all aspects of situational awareness in one location. The book also presents array theory, which is pivotal in finding the direction of arrival of acoustic signals. In addition, the book presents techniques to fuse the information from multiple homogeneous/heterogeneous sensors for better detection. MATLAB code is provided for majority of the real application, which is a valuable resource in not only understanding the theory but readers, can also use the code...

  18. Acoustics Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fisheries acoustics data are collected from more than 200 sea-days each year aboard the FRV DELAWARE II and FRV ALBATROSS IV (decommissioned) and the FSV Henry B....

  19. High-Fidelity Prediction of Launch Vehicle Lift-off Acoustic Environment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Launch vehicles experience extreme acoustic loads during liftoff driven by the interaction of rocket plumes and plume-generated acoustic waves with ground...

  20. ISOLDE PROGRAMME

    CERN Multimedia

    Fedosseev, V; Lynch, K M; Grob, L K; Herfurth, F; Scheidenberger, C; Geppert, C; Gorges, C; Ratajczyk, T; Vogel, S; Munch, M K; Nieminen, P; Pakarinen, J J A; Lecesne, N; Bouzomita, H; Grinyer, J; Marques moreno, F M; Parlog, M; Pedroza, J; Ghetta, V; Lozeva, R; Guillemaud mueller, D S; Cottereau, E; Cheikh mhamed, M; Tusseau nenez, S; Tungate, G; Walker, P M; Smith, A G; Fitzpatrick, C; Dominik, W M; Karny, M; Ciemny, A A; Nyman, G H; Thies, R M A; Lindberg, S K G; Langouche, G F; Delaure, B J P; Mayet, P; Ory, G T; Kesteloot, N J K; Papuga, J; Dehairs, M H R; Callens, M; Domnanich, K A; Richter, D; Lutter, R J; Wiehr, S; Tengblad, O; Nacher gonzalez, E; Jungclaus, A; Ribeiro jimenez, G; Marroquin alonso, I; Cal gonzalez, J; Paziy, V; Salsac, M; Murphy, C; Podolyak, Z F; Bajoga, A D; Butler, P; Pritchard, A; Steer, A N; Fox, S P; Wadsworth, B A; Truesdale, V L; Al monthery, M; Hass, M; Guttormsen, M S; Badea, M N; Calinescu, S; Cederkall, J A; Zemlyanoy, S; Golovkov, M; Wu, C; Harrichunder, S; Ncube, M; Gerten, R F; Lehnert, J; Gladnishki, K A; Pospisil, S; Datta pramanik, U; Benzoni, G; Fedorov, D; Molkanov, P; Pfeiffer, B; Griesel, T; Wehner, L W; Mikkelsen, M; Recchia, F; Smith, J F; Kelly, C M; De melo bandeira tavares, P M; Vieira, J M; Martins da silva, M A; Lima lopes, A M; Mader, J; Kessler, P; Laurent, B G; Schweikhard, L C; Marx, G H; Kulczycka, E; Komorowska, M; Da silva, M F; Goncalves marques, C P; Baptista peres, M A; Welander, J E; Coeck, S; Ryssens, W A M; Knoops, G; Vanbuel, J; Reiter, P; Miller, C; Martin sanchez-cano, D; Wiens, A; Blazhev, A A; Braun, N; Cappellazzo, M V; Birkenbach, B; Gerst, R; Dannhoff, M F; Sithole, M J; Bilgier, B; Nardelli, S; Vetter, U; Araujo mendes, C M; Valencia marin, E; Pantea, E; Hessberger, F P; Leduc, A J; Mitsuoka, S; Carbonari, A W; Buchegger, F J; Garzon camacho, A; Stachura, M K; Stora, T; Marsh, B A; Thiboud, J A; Antalic, S; Stahl, C; Bauer, C; Thurauf, M; Maass, B; Sturm, S; Boehm, C; Ways, M; Heylen, H; Riisager, K; Ruotsalainen, P A; Bastin, B; Duval, F T; Penessot, G; Flechard, X D; Desrues, P; Giovinazzo, J; Blank, B A; Kurtukian nieto, T; Ascher, P E L; Roccia, S; Matea, I; Croizet, H A G; Bonnin, C M; Morfouace, P; Smith, A J; Guin, R; Banerjee, D; Ohtsubo, T; Zhukov, M V; Tengborn, E A; Dessagne, P; Juscamaita vivanco, Y; De rydt, M A E; Vermaelen, P; Monten, R; Yang, X; De coster, A; Kruecken, R; Nowak, A K; Cano ott, D; Murphy, A S J; Shand, C M; Regan, P H; Jones, G D; Herzberg, R; Ikin, P; Davies, P J; Napoli, D R; Scarel, G; Larsen, A; Tornyi, T G; Pascu, S G; Stroe, L; Toma, S; Jansson, K; Dronjak fahlander, M; Krupko, S; Hurst, A M; Veskovic, M; Nikolov, J; Sibanda, W N; Rocchini, M; Deicher, M; Wichert, T; Wolf, E; Kronenberg, J; Helmke, A; Meliani, Z; Ivanov, V S; Kuti, I; Halasz, Z; Henry, M O; Bras de sequeira amaral, V; Espirito santo, F; Carvalho teixeira, R C; Rosendahl, S; Speidel, K; Agarwal, I; Faul, T; Kownacki, J M; Martins correia, J G; Lorenz, K; Costa miranda, S M; Granadeiro costa, A R; Da costa pereira, L M; Keupers, M; Stukken, R; Wursten, E J; Kotthaus, T; Pfeiffer, M; Stegemann, S T; Gironi, L; Cakirli, R B; Jensen, A; Romstedt, F; Constantino silva furtado, I; Heredia cardona, J A; Jordan martin, M D; Montaner piza, A; Plewinski, F; Mesli, A; Pichard, A; Fallis starhunter, J P; Voulot, D; Mrazek, J; Ugryumov, V; Savreux, R P; Kojouharov, I M; Stegmann, R; Fitting, J; Lauer, M; Kirsebom, O S; Jensen, K L; Jokinen, A; Rahkila, P J; Hager, U D K; Dubois, M; Orr, N A; Fabian, X; Huikari, J E; Goigoux, T; Magron, C; Zakari, A A; Maietta, M; Bachelet, C E M; Roussiere, B; Li, R; Foster, R M; Mertzimekis, T; Gislason, H P; Shayestehaminzadeh, S; Qi, B; Mukai, M; Watanabe, Y; Willmann, L; Kurcewicz, W; Wimmer, K; Meisel, Z P; Lievens, P; Neyens, G; Darby, I G; Descamps, B O; Ceruti, S; Bunka, M; Vermeulen, C; Podadera aliseda, I; Alcorta moreno, M; Pesudo fortes, V; Algora, A; Zielinska, M; Korten, W; Wang, C H; Lotay, G J; Mason, P; Rice, S J; Willenegger, L M; Judson, D S; Revill, J P; Andreev, A; Yavuzkanat, N; Kumar, V; Zamfir, N - V; Deleanu, D; Jeppesen, H B; Pain, S D; Stracener, D W; Matousek, V; Venhart, M; Birova, M; Li, X; Stuchbery, A E; Lellep, G M; Chakraborty, S; Leoni, S; Chupp, T; Yilmaz, C; Severin, G; Garcia ramos, J E; Hadinia, B; Mc glynn, E; Monteiro de sena silvares de carvalho, I; Friedag, P; Koos, V; Meot, V H; Pauwels, D B; Jancso, A; Srebrny, J; Alves, E J; David bosne, E; Dexters, W M M; Velten, P; Kalkuehler, M; Albers, M; Bharuth-ram, K; Akkus, B; Hemmingsen, L B S; Pedersen, J T; Dos santos redondo, L M; Rubio barroso, B; Kozlov, V; Mokhles gerami, A; Bernardo da silva, E; Unzueta solozabal, I; Schell, J; Szybowicz, M; Lassen, J; Johnston, K; Miyazaki, A; Macko, M; Coquard, L; Bloch, T P; Bonig, E S; Ignatov, A; Paschalis, S; Schilling, M; Habermann, T; Von hahn, R; Minaya ramirez, E E; Manea, V; Karthein, J; Moore, I D; Wang, Y; Saastamoinen, A J; Grahn, T; Herzan, A; Stolze, S M; Clement, E; Dijon, A; Shornikov, A; Lienard, E; Gibelin, J D; Pain, C; Canchel, G; Simpson, G S; Latrasse, L P; Forest, D H; Billowes, J; Flanagan, K; Strashnov, I; Binnersley, C L; Simpson, J; Morrall, P S; Grant, A F; Charisopoulos, S; Lagogiannis, A; Bhattacharya, C; Olafsson, S; Tornqvist, H T; Heinz, A M; White iv, E R; Vermote, S L; Courtin, S; Marechal, F; Randisi, G; Rajabali, M M; Lannoo, B J M; Frederickx, R; De coster, T J C; Roovers, N; De lemos lima, T A; Haller, S; Rizzi, M; Reichert, S B; Bonn, J; Thirolf, P G; Garcia rios, A R; Gugliermina, V M; Cubero campos, M A; Sanchez tembleque, V; Benito garcia, J; Senoville, M; Mountford, D J; Gelletly, W; Alharbi, T S T; Wilson, E; Rigby, S V; Andreoiu, C; Paul, E S; O'neill, G G; Harkness, L J; Wraith, C; Van esbroeck, K; Wadsworth, R; Cubiss, J G; Doherty, D T; Harding, R; Vaintraub, S; Mandal, S K; Hadynska-klek, K; Scarpa, D; Hoff, P; Syed naeemul, H; Borcea, R; Balabanski, D L; Marginean, R; Rotaru, F; Rudolph, D; Fahlander, C H; Chudoba, V; Naidoo, D; Veselsky, M; Kliman, J; 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Van den bergh, P A M; Raabe, R; Depuydt, M J F; Radulov, D P; Elseviers, J; Reynders, K L T; Sels, S M C; Verlinde, M; Delombaerde, L; De maesschalck, D; Tarasava, K; Gernhaeuser, R A; Weinzierl, W; Wendt, K; Achtzehn, T; Gottwald, T; Schug, M; Rossel, R E; Dominguez reyes, R R; Briz monago, J A; Koester, U H; Bunce, M R; Bowry, M D; Nakhostin, M; Shearman, R; Cresswell, J R; Joss, D T; Gredley, A; Groombridge, D; Siem, S; Weterings, J A; Renstrom, T; Szpak, B T; Luczkowski, M J; Ghita, D; Bezbakh, A; Bollmann, J; Bhattacharya, P; Roy, S; Rahaman, M A; Wlodarski, T; Carvalho soares, J; Barzakh, A; Werner, V R; Schertz, F; Froemmgen, N E; Liberati, V; Foy, B E; Weinheimer, C P; Zboril, M; Figuera, P; Simon, R E; Popescu, L A; Czosnyka, T; Miranda jana, P A; Buescher, J S L; Plociennik, W A; Ruchowska, E E; Chiara, C J; Eberth, J H; Thomas, T; Thole, P; Queiser, M T; Lo bianco, G; D'amico, F; Muller, S; Sanchez alarcon, R M; Tain enriquez, J L; Orrigo, S E A; Orlandi, R; Plazaola muguruza, F C; 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Vidal, M; Perez liva, M; Calvo portela, P; Ulla pedrera, F J; Domingo pardo, C; Morales lopez, A I; Wood, R T; Lalkovski, S; Page, R; Petri, M; Barton, C J; Nichols, A J; Vermeulen, M J; Bloor, D M; Henderson, J; Wilson, G L; De angelis, G; Buerger, A; Klintefjord, M L; Fornal, B A; Marginean, R; Sava, T; Suvaila, R; Lica, R; Costache, C; Mihai, R; Ionescu, A; Baeck, T M; Masenda, H; Sedlak, M; Koskelo, O K; Kyaw myat, K M; Ganguly, B; Goncalves marques, J; Cardoso, S; Seliverstov, M; Niessen, B D; Gutt, L E; Chapman, R; Spagnoletti, P N; Lopes, C; De oliveira amorim, C; Batista lopes, C M; Araujo, J; Schielke, S J; Daugas, J R; Gaudefroy, L; Chevrier, R; Szunyogh, D M; Napiorkowski, P J; Wrzosek-lipska, K; Wahl, U; Catarino, N; Pereira carvalho alves de sequeira, M; Decoster, S J; Porobic, T; Walters, W; Hess, H E; Holler, A; Bettermann, L; Geibel, K; Taprogge, J; Lewandowski, L T N; Manchado de sola, F; Das gupta, S; Thulstrup, P W; Heinz, U; Neidherr, D M; Gumenyuk, O; Peaker, A R; Wakabayashi, Y; Roder, J; Abrahams, K J; Mach, H A; Souza ribeiro junior, I; He, J; Giles, T J; Dorsival, A; Kalaninova, Z; Venos, D; Kraemer, J; Saha, S; Neugart, R; Eronen, T O; Kreim, K D; Heck, M K; Goncharov, M; Julin, R J; Jakobsson, E H U; Eleon, C; Achouri, N L; Fontbonne, C M; Alfaurt, P; Kusoglu, A; Wilkins, S G; Brown, A R; Imai, N; Pomorski, M J; Janiak, L; Nilsson, T; Stroke, H H; Stanja, J; Dangelser, E; Heenen, P; Mallion, S N; Diriken, J V J; Ghys, L H L; Khamehchi, M A; Van beveren, C; Gins, W A M; Bouma, J T; Mcnulty, J F; Berger, C J; Ohlert, C M; Schwerdtfeger, W; Becerril reyes, A D; Perea martinez, A; Martinez perez, M C; Margerin, V; Rudigier, M; Alexander, T D; Patel, Z V; Hammond, N; Wearing, F; Patel, A; Jenkins, D G; Debernardi, A; Giacoppo, F; Tveten, G M; Krolas, W A; Stanoiu, M A; Rickert, E U; Ter-akopian, G; Cline, D; Riihimaeki, I A; Simon, K D; Wagner, F E; Turker, M; Neef, M H; Jakubek, J; Vagena, E; Bottoni, S; Nishimura, K; Correia, J; Rodrigues valdrez, C J; Ostrowski, A N; Hallmann, O; Scheck, M; Wady, P T; Lane, J; Krasznahorkay, A J; Kunne sohler, D; Meaney, A J; Baptista barbosa, M; Hochschulz, F; Roig, O; Houngbo, D; Behan, C C; Kargoll, S; Kemnitz, S; Redondo cubero, A; Dirkx, D; Tallarida, G; Kaczarowski, R; Finke, F; Linnemann, A; Altenkirch, R; Saed-samii, N; Ansari, S H; Dlamini, W B; Adoons, V N; Ronning, C R; Guadilla gomez, V; Herlert, A J; Judge, S M; Catherall, R; Lettry, J; Lindroos, M; Wenander, F J C; Madurga flores, M; Zakoucky, D; Catchen, G L; Noertershaeuser, W; Kroell, T; Leske, J; Shubina, D; Murray, I M; Pancin, J; Delaunay, F; Poincheval, J J L; Audirac, L L; Gerbaux, M T; Aouadi, M; Sole, P G P; Fallot, M P; Onillon, A; Duchemin, C; Formento cavaier, R; Audi, G; Lau, C; Martin, J A; Barre, N H; Berry, T A; Procter, T J; Farooq-smith, G J; Bladen, L K; Axiotis, M; Muto, S; Jeong, S C; Hirayama, Y; Korgul, A B; Minamisono, K; Bingham, C R; Aprahamian, A; Bucher, B M; Huyse, M L; Himpe, P; Ferrer garcia, R; Sambi, S; Budincevic, I; Neven, M; Bomans, P; Romano, N; Maugeri, E A; Klupp, S C; Dehn, M H; Heinke, R M; Maira vidal, A; Vedia fernandez, M V; Ibanez garcia, P B; Bruyneel, B J E; Materna, T; Al-dahan, N; Alazemi, N; Carroll, R J; Babcock, C; Laird, A M; Eleme, Z; Dhal, A; Valiente dobon, J J; Sahin, E; Goergen, A; Maj, A; Bednarczyk, P A; Borcea, C; Negoita, F; Suliman, G; Marginean, N M; Sotty, C O; Negret, A L; Nae, S A; Nita, C; Golubev, P I; Knyazev, A; Jost, C U; Petrik, K; Strisovska, J; Vaeyrynen, S A; Dracoulis, G D; Rainovski, G I; Uher, J; Fernandez dominguez, B; Chakraborty, P; Avigo, R; Galaviz redondo, D; Castro ribeiro da silva, M; Bernards, C W; Falahat, S; Lekovic, F; Dorrer, H J; Derkx, X; Angus, L J; Sandhu, K S; Gregor, E; Byrne, D J; Haas, H; Lourenco, A A; Sousa pereira, S M; Esteves de araujo, J P; Sousa, J B; De melo mendonca, T M; Tavares de sousa, C; Guerreiro dos santos oliveira custodio, L M; Da rocha rodrigues, P M; Yamaguchi, T; Thompson, P C; Rosenbusch, M; Wienholtz, F; Fischer, P; Iwanicki, J S; Rusek, K M; Hanstorp, D; Severijns, N; Vanpoucke, B R S; Finlay, P E J; Park, S H; Warr, N V; Doornenbal, P C; Imig, A; Seidlitz, M; Moschner, K; Vogt, A; Kaya, L; Martel bravo, I; Orduz, A K; Serot, O; Litvinov, Y; Bommert, M; Hensel, S; Markevich, V; Nishio, K; Ota, S; Matos, I; Zenkevich, A; Picado sandi, E; Forstner, O

    2002-01-01

    The experiments aim at a broad exploration of the properties of atomic nuclei far away from the region of beta stability. Furthermore, the unique radioactive beams of over 60~elements produced at the on-line isotope separators ISOLDE-2 and ISOLDE-3 are used in a wide programme of atomic, solid state and surface physics. Around 300 scientists are involved in the project, coming from about 70 laboratories. \\\\ \\\\ The electromagnetic isotope separators are connected on-line with their production targets in the extracted 600 MeV proton or 910~MeV Helium-3 beam of the Synchro-Cyclotron. Secondary beams of radioactive isotopes are available at the facility in intensities of 10$^1

  1. Holograms for acoustics

    Science.gov (United States)

    Melde, Kai; Mark, Andrew G.; Qiu, Tian; Fischer, Peer

    2016-09-01

    Holographic techniques are fundamental to applications such as volumetric displays, high-density data storage and optical tweezers that require spatial control of intricate optical or acoustic fields within a three-dimensional volume. The basis of holography is spatial storage of the phase and/or amplitude profile of the desired wavefront in a manner that allows that wavefront to be reconstructed by interference when the hologram is illuminated with a suitable coherent source. Modern computer-generated holography skips the process of recording a hologram from a physical scene, and instead calculates the required phase profile before rendering it for reconstruction. In ultrasound applications, the phase profile is typically generated by discrete and independently driven ultrasound sources; however, these can only be used in small numbers, which limits the complexity or degrees of freedom that can be attained in the wavefront. Here we introduce monolithic acoustic holograms, which can reconstruct diffraction-limited acoustic pressure fields and thus arbitrary ultrasound beams. We use rapid fabrication to craft the holograms and achieve reconstruction degrees of freedom two orders of magnitude higher than commercial phased array sources. The technique is inexpensive, appropriate for both transmission and reflection elements, and scales well to higher information content, larger aperture size and higher power. The complex three-dimensional pressure and phase distributions produced by these acoustic holograms allow us to demonstrate new approaches to controlled ultrasonic manipulation of solids in water, and of liquids and solids in air. We expect that acoustic holograms will enable new capabilities in beam-steering and the contactless transfer of power, improve medical imaging, and drive new applications of ultrasound.

  2. Reactor Physics Programme

    Energy Technology Data Exchange (ETDEWEB)

    De Raedt, C

    2000-07-01

    The Reactor Physics and Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis on reactor fuel. This expertise is applied within the Reactor Physics and MYRRHA Research Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments. Progress and achievements in 1999 in the following areas are reported on: (1) investigations on the use of military plutonium in commercial power reactors; (2) neutron and gamma calculations performed for BR-2 and for other reactors; (3) the updating of neutron and gamma cross-section libraries; (4) the implementation of reactor codes; (6) the management of the UNIX workstations; and (6) fuel cycle studies.

  3. Test-driven programming

    Science.gov (United States)

    Georgiev, Bozhidar; Georgieva, Adriana

    2013-12-01

    In this paper, are presented some possibilities concerning the implementation of a test-driven development as a programming method. Here is offered a different point of view for creation of advanced programming techniques (build tests before programming source with all necessary software tools and modules respectively). Therefore, this nontraditional approach for easier programmer's work through building tests at first is preferable way of software development. This approach allows comparatively simple programming (applied with different object-oriented programming languages as for example JAVA, XML, PYTHON etc.). It is predictable way to develop software tools and to provide help about creating better software that is also easier to maintain. Test-driven programming is able to replace more complicated casual paradigms, used by many programmers.

  4. Acoustic biosensors.

    Science.gov (United States)

    Fogel, Ronen; Limson, Janice; Seshia, Ashwin A

    2016-06-30

    Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors. PMID:27365040

  5. Acoustic emission

    International Nuclear Information System (INIS)

    This paper is related to our activities on acoustic emission (A.E.). The work is made with different materials: metals and fibre reinforced plastics. At present, acoustic emission transducers are being developed for low and high temperature. A test to detect electrical discharges in electrical transformers was performed. Our experience in industrial tests to detect cracks or failures in tanks or tubes is also described. The use of A.E. for leak detection is considered. Works on pattern recognition of A.E. signals are also being performed. (Author)

  6. Acoustic streaming jets: A scaling and dimensional analysis

    Energy Technology Data Exchange (ETDEWEB)

    Botton, V., E-mail: valery.botton@insa-lyon.fr; Henry, D.; Millet, S.; Ben-Hadid, H. [LMFA, UMR CNRS 5509, Université de Lyon, ECL/INSA Lyon/Univ. Lyon 1, 36 avenue Guy deCollongue, 69134 Ecully Cedex (France); Moudjed, B. [LMFA, UMR CNRS 5509, Université de Lyon, ECL/INSA Lyon/Univ. Lyon 1, 36 avenue Guy deCollongue, 69134 Ecully Cedex (France); LIEFT, CEA-Saclay, 91191 Gif-sur-Yvette cedex (France); Garandet, J. P. [LIEFT, CEA-Saclay, 91191 Gif-sur-Yvette cedex (France)

    2015-10-28

    We present our work on acoustic streaming free jets driven by ultrasonic beams in liquids. These jets are steady flows generated far from walls by progressive acoustic waves. As can be seen on figure 1, our set-up, denominated AStrID for Acoustic Streaming Investigation Device, is made of a water tank in which a 29 mm plane source emits continuous ultrasonic waves at typically 2 MHz. Our approach combines an experimental characterization of both the acoustic pressure field (hydrophone) and the obtained acoustic streaming velocity field (PIV visualization) on one hand, with CFD using an incompressible Navier-Stokes solver on the other hand.

  7. Acoustic streaming jets: A scaling and dimensional analysis

    International Nuclear Information System (INIS)

    We present our work on acoustic streaming free jets driven by ultrasonic beams in liquids. These jets are steady flows generated far from walls by progressive acoustic waves. As can be seen on figure 1, our set-up, denominated AStrID for Acoustic Streaming Investigation Device, is made of a water tank in which a 29 mm plane source emits continuous ultrasonic waves at typically 2 MHz. Our approach combines an experimental characterization of both the acoustic pressure field (hydrophone) and the obtained acoustic streaming velocity field (PIV visualization) on one hand, with CFD using an incompressible Navier-Stokes solver on the other hand

  8. NDA National Graduate Programme 'nucleargraduates'

    International Nuclear Information System (INIS)

    leading technical proficiency mixed with indications of 'high performer' potential. Professional - Throughout the programme the graduates will be working towards achieving professional qualifications though the relevant 'Institute' for their discipline, such as the IMECHE. The training and experience gained from the scheme is programmed around a syllabus of work and courses, which will be accredited retrospectively by the 'Institutes'. The two year 'initial professional development' programme whilst the graduate is with the NDA is then fitted into a further two years with stakeholders for their first 'substantive role'. Whilst there is no monetary contribution from the stakeholders there is a significant resource support from the programme stakeholders. They will provide a sophisticated matrix of support in attraction and assessment support, professional development, mentoring, training and scheme evaluation. The programme will be using cutting edge marketing, assessment, recruitment and training tools. It will also deliver a pioneering socio economic programme that will combine professional training with cultural and behavioural insight work. The aims of the programme are aligned with the NDA succession plan and Skills Strategy Document. The graduate profile by the end of the two year programme is 'mobile, professional, aware and ambitious.' The Programme is driven by a group comprising of companies across the industry including the NDA, SLC's, defence operators, operational power station organisations, regulators and the supply chain. Uniquely, the programme offers no 'specific job' with the NDA after the two year programme is completed. The programme will be integrated into the existing partners' schemes to ensure smooth progression. The Graduate's progress after 2 years will be facilitated by a careers service and formal rules governing the behaviour of partners. The first cohort targeted graduates from the following disciplines areas: Civil and Mechanical Engineering

  9. Olympic Partner Programme

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Olympic Partner Programme (TOP) is an international Olympic marketing programme created by the International Olympic Committee (IOC),which includes the Organising Committees of the Games,the National Olympic Committees and the TOP Partners.

  10. UNESCO's Ethics Education Programme.

    NARCIS (Netherlands)

    Have, H.A.M.J. ten

    2008-01-01

    Unesco initiated the Ethics Education Programme in 2004 at the request of member states to reinforce and increase the capacities in the area of ethics teaching. The programme is focused on providing detailed information about existing teaching programmes. It also develops and promotes teaching throu

  11. International Programmes on ADS: IAEA

    International Nuclear Information System (INIS)

    The IAEA recognizes that there are four major challenges facing the long term development of nuclear energy as a part of the world’s energy mix: improvement of the economic competitiveness, meeting increasingly stringent safety requirements, adhering to the criteria of sustainable development, and public acceptance. Meeting the sustainability criteria is the driving force behind IAEA’s activity in the area of innovative transmutation reactor technology development and, in particular, Accelerator Driven Systems. The framework for all the IAEA activities in the ADS area is the Technical Working Group on Fast Reactors (TWG-FR). In response to strong common R&D needs in the Member States, the TWG-FR acts as a catalyst for international information exchange and collaborative R&D. It provides a forum for exchange of non-commercial scientific and technical information, and a forum for international cooperation on generic research and development programmes on advances in fast reactors and fast spectrum accelerator driven systems. Its present members are the following 15 IAEA Member States: Belarus, Brazil, China, France, Germany, India, Italy, Japan, Kazakhstan, Republic of Korea, Russian Federation, Sweden, Switzerland, United Kingdom, and United States of America, as well as 3 international organizations: ISTC, OECD-NEA, and EU (EC). As observers, the TWG-FR has welcomed Argentina and Belgium. Last but not least, the IAEA is providing the ADS Research and Development Database. It contains information about ADS related R&D programmes, existing and planned experimental facilities as well as programmes, methods and data development efforts, design studies, and so forth

  12. Outcomes-based planning and implementation led to the success of the Hawaii fruit fly suppression programme: Implications to adoption of area-wide programmes

    International Nuclear Information System (INIS)

    Full text: A critical component of successful area-wide pest management (AWPM) programmes are organised, coordinated and comprehensive outreach educational programmes. The Hawaii area-wide fruit fly pest management (HAW-FLYPM) programme's educational programme, a part of a USDA AWPM programme in Hawaii, utilised the 'logic model' approach to organise, plan, execute and evaluate farmer and community educational programmes statewide. The logic model approach was an outcome-driven rather than activity based method that employed a linear sequence that developed relationships between programme inputs, outputs and outcomes. This model was utilised extensively to transfer sustainable, science-based technologies to suppress tephritid fruit fly pests. HAW-FLYPM's educational programme targeted growers and community door yard growers, three teaching curricula aimed at elementary through high school students, and a statewide awareness programme for the public at large. Additional key components of the HAW-FLYPM education programme was the development of implementation schedules used to track programme progress, a comprehensive media matrix developed to ensure educational materials met the needs of target audience groups, and a sustainability calculator to assess the likelihood of programme sustainability after the initial five year funding cycle. The model served as a 'blue print' for ensuring programme elements were planned, delivered and executed on a timely basis. Utilisation of the logic model to organise efforts and manage diverse, multi agency programmes such as the HAW-FLYPM programme has shown to be a successful method of programme advancement and outcome achievement. (author)

  13. Product Sound: Acoustically pleasant motor drives

    DEFF Research Database (Denmark)

    Mathe, Laszlo

    The work in this thesis is focused on the acoustic noise generated by electrical motors driven by a pulse width modulated (PWM) power electronic inverter. In a usual inverter based electrical drive, the modulation uses fixed switching frequency; that introduces a set of harmonics in the acoustic...... spectra transforming the acoustic noise generated by the motor in a strong whistling noise. To maintain high efficiency for the entire drive, the switching frequency is typically kept around 4 kHz. However, this is the range where the human ear is the most sensitive. The main goal of this thesis...... modulation method is that it can be easily retrofit in a prior implemented open- or closed-loop control algorithm, without adding any extra hardware components. Typically, for application in heating ventilation and air condition (HVAC), the main focus is on cost, efficiency and acoustic noise, while high...

  14. Acoustic propagational characteristics and tomography studies of the northern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Somayajulu, Y.K.; Murty, T.V.R.

    duration acoustic tomography experiment in the eastern Arabian Sea during summer 1993 are presented in section 5. The Heard Island experiment, and India's contribution to this joint programme is outlined in section....

  15. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available Educational Video Home What is an AN What is an Acoustic Neuroma? Identifying an AN Symptoms Acoustic Neuroma Keywords Educational Video ... for pre- and post-treatment acoustic neuroma patients. Home What is an AN What is an Acoustic ...

  16. Acoustic telemetry.

    Energy Technology Data Exchange (ETDEWEB)

    Drumheller, Douglas Schaeffer; Kuszmaul, Scott S.

    2003-08-01

    Broadcasting messages through the earth is a daunting task. Indeed, broadcasting a normal telephone conversion through the earth by wireless means is impossible with todays technology. Most of us don't care, but some do. Industries that drill into the earth need wireless communication to broadcast navigation parameters. This allows them to steer their drill bits. They also need information about the natural formation that they are drilling. Measurements of parameters such as pressure, temperature, and gamma radiation levels can tell them if they have found a valuable resource such as a geothermal reservoir or a stratum bearing natural gas. Wireless communication methods are available to the drilling industry. Information is broadcast via either pressure waves in the drilling fluid or electromagnetic waves in the earth and well tubing. Data transmission can only travel one way at rates around a few baud. Given that normal Internet telephone modems operate near 20,000 baud, these data rates are truly very slow. Moreover, communication is often interrupted or permanently blocked by drilling conditions or natural formation properties. Here we describe a tool that communicates with stress waves traveling through the steel drill pipe and production tubing in the well. It's based on an old idea called Acoustic Telemetry. But what we present here is more than an idea. This tool exists, it's drilled several wells, and it works. Currently, it's the first and only acoustic telemetry tool that can withstand the drilling environment. It broadcasts one way over a limited range at much faster rates than existing methods, but we also know how build a system that can communicate both up and down wells of indefinite length.

  17. Use of acoustic vortices in acoustic levitation

    DEFF Research Database (Denmark)

    Cutanda Henriquez, Vicente; Santillan, Arturo Orozco; Juhl, Peter Møller

    2009-01-01

    Acoustic fields are known to exert forces on the surfaces of objects. These forces are noticeable if the sound pressure is sufficiently high. Two phenomena where acoustic forces are relevant are: i) acoustic levitation, where strong standing waves can hold small objects at certain positions......, counterbalancing their weight, and ii) acoustic vortices, spinning sound fields that can impinge angular momentum and cause rotation of objects. In this contribution, both force-creating sound fields are studied by means of numerical simulations. The Boundary Element Method is employed to this end. The simulation...... of acoustical vortices uses an efficient numerical implementation based on the superposition of two orthogonal sound fields with a delay of 90° between them. It is shown that acoustic levitation and the use of acoustic vortices can be combined to manipulate objects in an efficient and controlled manner without...

  18. Acoustic dispersive prism

    OpenAIRE

    Hussein Esfahlani; Sami Karkar; Herve Lissek; Mosig, Juan R.

    2016-01-01

    The optical dispersive prism is a well-studied element, which allows separating white light into its constituent spectral colors, and stands in nature as water droplets. In analogy to this definition, the acoustic dispersive prism should be an acoustic device with capability of splitting a broadband acoustic wave into its constituent Fourier components. However, due to the acoustical nature of materials as well as the design and fabrication difficulties, there is neither any natural acoustic ...

  19. Y-shaped jets driven by an ultrasonic beam reflecting on a wall

    OpenAIRE

    Moudjed, Brahim; Botton, Valéry; Henry, Daniel; Millet, Séverine; Ben Hadid, Hamda

    2016-01-01

    International audience This paper presents an original experimental and numerical investigation of acoustic streaming driven by an acoustic beam reflecting on a wall. The water experiment features a 2 MHz acoustic beam totally reflecting on one of the tank glass walls. The velocity field in the plane containing the incident and reflected beam axes is investigated using Particle Image Velocimetry (PIV). It exhibits an original y-shaped structure: the impinging jet driven by the incident bea...

  20. Finnish bioenergy research programme

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, D. [VTT Energy, Jyvaeskylae (Finland)

    1996-12-31

    Finland is a leading country in the use of biofuels and has excellent opportunities to increase the use of biofuels by up to 25-30 %. The Finnish Government has set an objective for the promotion of bioenergy. The aim is to increase the use of bioenergy by about 25 % from the present level by 2005, and the increment corresponds to 1.5 million tonnes of oil equivalent (toe) per year. The R and D work has been considered as an important factor to achieve this ambitious goal. Energy research was organised into a series of research programmes in 1988 in accordance with the proposal of Finnish Energy Research Committee. The object of the research programmes is to enhance research activities and to bundle individual projects together into larger research packages. The common target of the Finnish energy research programmes is to proceed from basic and applied research to product development and pilot operation, and after that to the first commercial applications, e.g. demonstrations. As the organisation of energy research to programmes has led to good results, the Finnish Ministry of Trade and Industry decided to go on with this practice by launching new six-year programmes in 1993-1998. One of these programmes is the Bioenergy Research Programme and the co-ordination of this programme is carried out by VTT Energy. Besides VTT Energy the Finnish Forest Research Institute, Work Efficiency Institute, Metsaeteho and University of Joensuu are participating in the programme 7 refs.

  1. Responsive acoustic surfaces

    DEFF Research Database (Denmark)

    Peters, Brady; Tamke, Martin; Nielsen, Stig Anton;

    2011-01-01

    Acoustic performance is defined by the parameter of reverberation time; however, this does not capture the acoustic experience in some types of open plan spaces. As many working and learning activities now take place in open plan spaces, it is important to be able to understand and design...... for the acoustic conditions of these spaces. This paper describes an experimental research project that studied the design processes necessary to design for sound. A responsive acoustic surface was designed, fabricated and tested. This acoustic surface was designed to create specific sonic effects. The design...... was simulated using custom integrated acoustic software and also using Odeon acoustic analysis software. The research demonstrates a method for designing space- and sound-defining surfaces, defines the concept of acoustic subspace, and suggests some new parameters for defining acoustic subspaces....

  2. Springer Handbook of Acoustics

    CERN Document Server

    Rossing, Thomas D

    2007-01-01

    Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and others. The Springer Handbook of Acoustics is an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents spanning: animal acoustics including infrasound and ultrasound, environmental noise control, music and human speech and singing, physiological and psychological acoustics, architectural acoustics, physical and engineering acoustics, signal processing, medical acoustics, and ocean acoustics. This handbook reviews the most important areas of acoustics, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest rese...

  3. Acoustic Spatiality

    Directory of Open Access Journals (Sweden)

    Brandon LaBelle

    2012-06-01

    Full Text Available Experiences of listening can be appreciated as intensely relational, bringing us into contact with surrounding events, bodies and things. Given that sound propagates and expands outwardly, as a set of oscillations from a particular source, listening carries with it a sensual intensity, whereby auditory phenomena deliver intrusive and disruptive as well as soothing and assuring experiences. The physicality characteristic of sound suggests a deeply impressionistic, locational "knowledge structure" – that is, the ways in which listening affords processes of exchange, of being in the world, and from which we extend ourselves. Sound, as physical energy reflecting and absorbing into the materiality around us, and even one's self, provides a rich platform for understanding place and emplacement. Sound is always already a trace of location.Such features of auditory experience give suggestion for what I may call an acoustical paradigm – how sound sets in motion not only the material world but also the flows of the imagination, lending to forces of signification and social structure, and figuring us in relation to each other. The relationality of sound brings us into a steady web of interferences, each of which announces the promise or problematic of being somewhere.

  4. Acoustic Neurinomas

    Directory of Open Access Journals (Sweden)

    Mohammad Faraji Rad

    2011-01-01

    Full Text Available Acoustic neuromas (AN are schwann cell-derived tumors that commonly arise from the vestibular portion of the eighth cranial nerve also known as vestibular schwannoma(VS causes unilateral hearing loss, tinnitus, vertigo and unsteadiness. In many cases, the tumor size may remain unchanged for many years following diagnosis, which is typically made by MRI. In the majority of cases the tumor is small, leaving the clinician and patient with the options of either serial scanning or active treatment by gamma knife radiosurgery (GKR or microneurosurgery. Despite the vast number of published treatment reports, comparative studies are few. The predominant clinical endpoints of AN treatment include tumor control, facial nerve function and hearing preservation. Less focus has been put on symptom relief and health-related quality of life (QOL. It is uncertain if treating a small tumor leaves the patient with a better chance of obtaining relief from future hearing loss, vertigo or tinnitus than by observing it without treatment.   In this paper we review the literature for the natural course, the treatment alternatives and the results of AN. Finally, we present our experience with a management strategy applied for more than 30 years.

  5. Acoustic monitoring techniques for corrosion degradation in cemented waste canisters

    International Nuclear Information System (INIS)

    This report describes work carried out to investigate acoustic emission as a monitor of corrosion and degradation of wasteforms where the waste is potentially reactive metal. Electronic monitoring equipment has been designed, built and tested to allow long-term monitoring of a number of waste packages simultaneously. Acoustic monitoring experiments were made on a range of 1 litre cemented Magnox and aluminium samples cast into canisters comparing the acoustic events with hydrogen gas evolution rates and electrochemical corrosion rates. The attenuation of the acoustic signals by the cement grout under a range of conditions has been studied to determine the volume of wasteform that can be satisfactorily monitored by one transducer. The final phase of the programme monitored the acoustic events from full size (200 litre) cemented, inactive, simulated aluminium swarf wastepackages prepared at the AEA waste cementation plant at Winfrith. (Author)

  6. Ultrafast magnetoelastic probing of surface acoustic transients

    Science.gov (United States)

    Janušonis, J.; Chang, C. L.; Jansma, T.; Gatilova, A.; Vlasov, V. S.; Lomonosov, A. M.; Temnov, V. V.; Tobey, R. I.

    2016-07-01

    We generate in-plane magnetoelastic waves in nickel films using the all-optical transient grating technique. When performed on amorphous glass substrates, two dominant magnetoelastic excitations can be resonantly driven by the underlying elastic distortions, the Rayleigh surface acoustic wave and the surface skimming longitudinal wave. An applied field, oriented in the sample plane, selectively tunes the coupling between magnetic precession and one of the elastic waves, thus demonstrating selective excitation of coexisting, large-amplitude magnetoelastic waves. Analytical calculations based on the Green's function approach corroborate the generation of multiple surface acoustic transients with disparate decay dynamics.

  7. Acoustic source for generating an acoustic beam

    Energy Technology Data Exchange (ETDEWEB)

    Vu, Cung Khac; Sinha, Dipen N.; Pantea, Cristian

    2016-05-31

    An acoustic source for generating an acoustic beam includes a housing; a plurality of spaced apart piezo-electric layers disposed within the housing; and a non-linear medium filling between the plurality of layers. Each of the plurality of piezoelectric layers is configured to generate an acoustic wave. The non-linear medium and the plurality of piezo-electric material layers have a matching impedance so as to enhance a transmission of the acoustic wave generated by each of plurality of layers through the remaining plurality of layers.

  8. Acoustic spin pumping in magnetoelectric bulk acoustic wave resonator

    Science.gov (United States)

    Polzikova, N. I.; Alekseev, S. G.; Pyataikin, I. I.; Kotelyanskii, I. M.; Luzanov, V. A.; Orlov, A. P.

    2016-05-01

    We present the generation and detection of spin currents by using magnetoelastic resonance excitation in a magnetoelectric composite high overtone bulk acoustic wave (BAW) resonator (HBAR) formed by a Al-ZnO-Al-GGG-YIG-Pt structure. Transversal BAW drives magnetization oscillations in YIG film at a given resonant magnetic field, and the resonant magneto-elastic coupling establishes the spin-current generation at the Pt/YIG interface. Due to the inverse spin Hall effect (ISHE) this BAW-driven spin current is converted to a dc voltage in the Pt layer. The dependence of the measured voltage both on magnetic field and frequency has a resonant character. The voltage is determined by the acoustic power in HBAR and changes its sign upon magnetic field reversal. We compare the experimentally observed amplitudes of the ISHE electrical field achieved by our method and other approaches to spin current generation that use surface acoustic waves and microwave resonators for ferromagnetic resonance excitation, with the theoretically expected values.

  9. Acoustic spin pumping in magnetoelectric bulk acoustic wave resonator

    Directory of Open Access Journals (Sweden)

    N. I. Polzikova

    2016-05-01

    Full Text Available We present the generation and detection of spin currents by using magnetoelastic resonance excitation in a magnetoelectric composite high overtone bulk acoustic wave (BAW resonator (HBAR formed by a Al-ZnO-Al-GGG-YIG-Pt structure. Transversal BAW drives magnetization oscillations in YIG film at a given resonant magnetic field, and the resonant magneto-elastic coupling establishes the spin-current generation at the Pt/YIG interface. Due to the inverse spin Hall effect (ISHE this BAW-driven spin current is converted to a dc voltage in the Pt layer. The dependence of the measured voltage both on magnetic field and frequency has a resonant character. The voltage is determined by the acoustic power in HBAR and changes its sign upon magnetic field reversal. We compare the experimentally observed amplitudes of the ISHE electrical field achieved by our method and other approaches to spin current generation that use surface acoustic waves and microwave resonators for ferromagnetic resonance excitation, with the theoretically expected values.

  10. SET-Routes programme

    CERN Document Server

    CERN audiovisual service

    2009-01-01

    The SET-Routes programme, launched in 2007 with the goal of attracting girls and young women to careers in science, came to an end in April this year. The result of a collaboration between EMBL, EMBO and CERN, the programme established a network of "ambassadors", women scientists who went out to talk about their careers in science at schools and universities across Europe.

  11. Canonical Acoustics and Its Application to Surface Acoustic Wave on Acoustic Metamaterials

    Science.gov (United States)

    Shen, Jian Qi

    2016-08-01

    In a conventional formalism of acoustics, acoustic pressure p and velocity field u are used for characterizing acoustic waves propagating inside elastic/acoustic materials. We shall treat some fundamental problems relevant to acoustic wave propagation alternatively by using canonical acoustics (a more concise and compact formalism of acoustic dynamics), in which an acoustic scalar potential and an acoustic vector potential (Φ ,V), instead of the conventional acoustic field quantities such as acoustic pressure and velocity field (p,u) for characterizing acoustic waves, have been defined as the fundamental variables. The canonical formalism of the acoustic energy-momentum tensor is derived in terms of the acoustic potentials. Both the acoustic Hamiltonian density and the acoustic Lagrangian density have been defined, and based on this formulation, the acoustic wave quantization in a fluid is also developed. Such a formalism of acoustic potentials is employed to the problem of negative-mass-density assisted surface acoustic wave that is a highly localized surface bound state (an eigenstate of the acoustic wave equations). Since such a surface acoustic wave can be strongly confined to an interface between an acoustic metamaterial (e.g., fluid-solid composite structures with a negative dynamical mass density) and an ordinary material (with a positive mass density), it will give rise to an effect of acoustic field enhancement on the acoustic interface, and would have potential applications in acoustic device design for acoustic wave control.

  12. Fusion technology programme

    International Nuclear Information System (INIS)

    KfK participates to the Fusion Technology Programme of the European Community. Most of the work in progress addresses the Next European Torus (NET) and the long term technology aspects as defined in the 82/86 programme. A minor part serves to preparation of future contributions and to design studies on fusion concepts in a wider perspective. The Fusion Technology Programme of Euratom covers mainly aspects of nuclear engineering. Plasma engineering, heating, refueling and vacuum technology are at present part of the Physics Programme. In view of NET, integration of the different areas of work will be mandatory. KfK is therefore prepared to address technical aspects beyond the actual scope of the physics experiments. The technology tasks are reported project wise under title and code of the Euratom programme. Most of the projects described here are shared with other European fusion laboratories as indicated in the table annexed to this report. (orig./GG)

  13. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Join/Renew Ways to Give ANA Discussion Forum ... ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Search ANAUSA.org Connect with us! Educational Video ...

  14. Atlantic Herring Acoustic Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Advanced Sampling Technologies Research Group conducts annual fisheries acoustic surveys using state-of-the-art acoustic, midwater trawling, and...

  15. Cystic acoustic neuromas

    OpenAIRE

    Chitkara, Naveen; Chanda, Rakesh; Yadav, S. P. S.; N.K. Sharma

    2002-01-01

    Predominantly cystic acoustic neuromas are rare and they usually present with clinical and radiological features different from their more common solid counterparts. Two cases of cystic acoustic neuromas are reported here.

  16. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... is ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic ... is ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic ...

  17. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ...

  18. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Resources Patient Surveys Related Links Clinical Trials.gov Health Care Insurance Toolkit Additional Resources ANA Public Webinars © 2016 Acoustic Neuroma Association Acoustic Neuroma Association ® • ...

  19. Analyese of acoustic and electromagnetic fields for the design of a two coil-driven electric transducer%双驱动电动换能器电磁场和声-结构耦合场分析

    Institute of Scientific and Technical Information of China (English)

    唐良雨

    2012-01-01

    Electric transducer design includes electromagnetic field and acoustic-structure coupling. This paper use COMSOL multi-physics analysis software which provides the two analysis modules to be combined. Deduced a formula for COMSOL numerical calculation based on electromagnetic theory, the combination of the two coupled field analysis. The use of electromagnetic field analysis process calculated the required variables, on behalf of the entering acoustic-structure coupled field analysis, the resultant sound field distribution. The article generally describes the COMSOL finite element modeling and the use of the two modules. This article will not discuss how to optimize electric transducer structure.%电动换能器的设计涉及电磁场和声-结构耦合问题,本文利用COMSOL多物理场分析软件提供的该两种分析模块进行组合,以电磁理论为基础推导出了适合COMSOL数值计算的公式,把两种耦合场的分析结合起来,利用电磁场分析过程计算所需要变量,代入声-结构耦合场进行分析,得到声场分布情况.文章也大致介绍了COMSOL的有限元建模和该两种模块的使用方法.本文对电动换能器结构如何优化不做讨论.

  20. REHABILITATION PRACTICAL PROGRAMME

    Directory of Open Access Journals (Sweden)

    Suzana KRANJC JOLDIKJ

    Full Text Available Centre for Education and Rehabilitation of Physi­cally Handicapped Children and Adolescents Kamnik (Zavod za usposabljanje invalidne mlad­ine Kamnik; hereinafter: ZUIM perform verified or state-ap­proved programme the Rehabilitation practical pro­gramme. The programme is intended for all those young people, who have completed primary school education, but cannot continue regular schooling in secondary school pro­grammes. The programme con­sists of several equivalent parts: education, practical work, train­ing work, health, therapeutic, psychologi­cal, and other activities. For every beginner in the first month of education members of the operative team create an individualized programme, which in­cludes individualized school work, individualized training programme, and other expert activities. The programme can last for 6 years maximum, it can however be completed earlier, when the op­erative team feels the training is no longer neces­sary. Pro­gress of a young person is what matters the most, and if there is no progress, the training is brought to an end. Training of young people in the Rehabilitation practical programme is only the be­ginning. The country will have to start considering social enter­prises, which are found elsewhere in the world, for example in Scandinavian countries and in the USA.

  1. Tutorial on architectural acoustics

    Science.gov (United States)

    Shaw, Neil; Talaske, Rick; Bistafa, Sylvio

    2002-11-01

    This tutorial is intended to provide an overview of current knowledge and practice in architectural acoustics. Topics covered will include basic concepts and history, acoustics of small rooms (small rooms for speech such as classrooms and meeting rooms, music studios, small critical listening spaces such as home theatres) and the acoustics of large rooms (larger assembly halls, auditoria, and performance halls).

  2. The European Fusion Programme

    International Nuclear Information System (INIS)

    The European Fusion Programme is coordinated by Euratom and represents a long term cooperative project of Member States of the European Communities in the field of fusion, designed to lead to the joint construction of prototypes. The main lines of the programme proposed for 1982 to 1986 are: (1) the continuation of a strong effort on tokamaks with emphasis on JET construction, operation and upgrading, (2) conceptual design of NET and development of the related technology, and (3) further work on two alternative magnetic confinement systems. The current status and future plans for this programme are discussed in the paper. (author)

  3. Acoustic elliptical cylindrical cloaks

    Institute of Scientific and Technical Information of China (English)

    Ma Hua; Qu Shao-Bo; Xu Zhuo; Wang Jia-Fu

    2009-01-01

    By making a comparison between the acoustic equations and the 2-dimensional (2D) Maxwell equations, we obtain the material parameter equations (MPE) for acoustic elliptical cylindrical cloaks. Both the theoretical results and the numerical results indicate that an elliptical cylindrical cloak can realize perfect acoustic invisibility when the spatial distributions of mass density and bulk modulus are exactly configured according to the proposed equations. The present work is the meaningful exploration of designing acoustic cloaks that are neither sphere nor circular cylinder in shape, and opens up possibilities for making complex and multiplex acoustic cloaks with simple models such as spheres, circular or elliptic cylinders.

  4. Greek Teachers Programme 2015

    CERN Multimedia

    Hoch, Michael

    2015-01-01

    The 3rd edition of this year's Greek Teachers Programme was co-organized by CERN Education Group and the Hellenic Physical Society and took place from 8 to 12 November 2015. The programme targets physics high-school teachers from all over Greece. It aims to help teachers inspire the next generation of scientists and engineers by motivating their students to understand and appreciate how science works at the world's largest physics laboratory, whereby increasing their interest in pursuing studies in STEM fields in secondary and post-secondary education. 33 teachers took part in this programme which comprised lectures by Greek members of the CERN scientific community, with visits to experimental facilities, hands-on activities and dedicated sessions on effective and creative ways through which participants may bring physics, particle physics and CERN closer to their school classroom. In 2015, more than 100 teachers took part in the three editions of the Greek Teachers Programme.

  5. Network virtualization and programmability

    OpenAIRE

    Colle, Didier; Jooris, Bart; Gurzi, Pasquale; Pickavet, Mario; Demeester, Piet

    2010-01-01

    We present network virtualization (building virtual or logical networks over a physical infrastructure) and network programmability (allowing the network operator to at least control the network but more fundamentally to define its behavior) concepts.

  6. Fellows, Associates & Students Programmes

    CERN Document Server

    2005-01-01

    The present document reviews the CERN Fellows, Associates and Students Programmes emphasizing the developments since 2000, when the previous review was presented to the Scientific Policy Committee, Finance Committee and Council (CERN/2325), and makes proposals for the coming five years. In summary, it is proposed to â?¢ Simplify the payment scheme for the Paid Scientific Associates Programme, which will no longer depend on candidateâ??s home support and age; â?¢ Broaden the scope of the Fellowship Programme, in order to facilitate the recruitment of young graduates in computing and engineering. Age-related eligibility conditions and payment levels will be replaced with experience-based criteria; â?¢ Modify subsistence rates for the Doctoral and Technical Student Programme in order to harmonize CERNâ??s payment levels with those offered by other research establishments. This document is presented for discussion and recommendation by the Scientific Policy Committee and approval by the Council. Additiona...

  7. Elukestva õppe programm : Erasmus+

    Index Scriptorium Estoniae

    2014-01-01

    Erasmus+ programm liidab senised koostööprogrammid „Euroopa elukestva õppe programm“, „Euroopa Noored“ ning Euroopa komisjoni rahvusvahelised kõrgharidusprogrammid. Elukestva õppe programmi 2013 kokkuvõte

  8. Punch Card Programmable Microfluidics

    OpenAIRE

    George Korir; Manu Prakash

    2014-01-01

    Small volume fluid handling in single and multiphase microfluidics provides a promising strategy for efficient bio-chemical assays, low-cost point-of-care diagnostics and new approaches to scientific discoveries. However multiple barriers exist towards low-cost field deployment of programmable microfluidics. Incorporating multiple pumps, mixers and discrete valve based control of nanoliter fluids and droplets in an integrated, programmable manner without additional required external component...

  9. Stay Safe Programme

    OpenAIRE

    MacIntyre, Deirdre; Carr, Alan.

    1999-01-01

    Objective. This child abuse prevention study aimed to evaluate the effectiveness of the Stay Safe Programme in training unscreened 7 and 10 year old children in personal safety skills. Subsidiary aims were to evaluate the programme's impact on children's self-esteem and parents' and teachers' knowledge and attitudes of relevance to child abuse and protection. Method. Changes in safety knowledge and skills and self-esteem of 339 children who participated in the Stay Safe Program...

  10. The Gold Standard Programme

    DEFF Research Database (Denmark)

    Neumann, Tim; Rasmussen, Mette; Ghith, Nermin;

    2013-01-01

    To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates.......To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates....

  11. ACOUSTICAL STANDARDS NEWS.

    Science.gov (United States)

    Stremmel, Neil; Struck, Christopher J

    2016-07-01

    American National Standards (ANSI Standards) developed by Accredited Standards Committees S1, S2, S3, S3/SC 1, and S12 in the areas of acoustics, mechanical vibration and shock, bioacoustics, animal bioacoustics, and noise, respectively, are published by the Acoustical Society of America (ASA). In addition to these standards, ASA publishes a catalog of Acoustical American National Standards. To receive a copy of the latest Standards catalog, please contact Neil Stremmel.Comments are welcomed on all material in Acoustical Standards News.This Acoustical Standards News section in JASA, as well as the National Catalog of Acoustical Standards and other information on the Standards Program of the Acoustical Society of America, are available via the ASA home page: http://acousticalsociety.org. PMID:27475185

  12. Acoustic streaming in microchannels

    DEFF Research Database (Denmark)

    Tribler, Peter Muller

    , the acoustic streaming flow, and the forces on suspended microparticles. The work is motivated by the application of particle focusing by acoustic radiation forces in medical, environmental and food sciences. Here acoustic streaming is most often unwanted, because it limits the focusability of particles...... work. Based on first- and second-order perturbation theory, assuming small acoustic amplitudes, we derived the time-dependent governing equations under adiabatic conditions. The adiabatic first- and second-order equations are solved analytically for the acoustic field between two orthogonally......-of-the-art in the field. Furthermore, the analytical solution for the acoustic streaming in rectangular channels with arbitrary large height-to-width ratios is derived. This accommodates the analytical theory of acoustic streaming to applications within acoustofluidics....

  13. Acoustic metamaterials: From local resonances to broad horizons.

    Science.gov (United States)

    Ma, Guancong; Sheng, Ping

    2016-02-01

    Within a time span of 15 years, acoustic metamaterials have emerged from academic curiosity to become an active field driven by scientific discoveries and diverse application potentials. This review traces the development of acoustic metamaterials from the initial findings of mass density and bulk modulus frequency dispersions in locally resonant structures to the diverse functionalities afforded by the perspective of negative constitutive parameter values, and their implications for acoustic wave behaviors. We survey the more recent developments, which include compact phase manipulation structures, superabsorption, and actively controllable metamaterials as well as the new directions on acoustic wave transport in moving fluid, elastic, and mechanical metamaterials, graphene-inspired metamaterials, and structures whose characteristics are best delineated by non-Hermitian Hamiltonians. Many of the novel acoustic metamaterial structures have transcended the original definition of metamaterials as arising from the collective manifestations of constituent resonating units, but they continue to extend wave manipulation functionalities beyond those found in nature.

  14. Frequency effects on the scale and behavior of acoustic streaming.

    Science.gov (United States)

    Dentry, Michael B; Yeo, Leslie Y; Friend, James R

    2014-01-01

    Acoustic streaming underpins an exciting range of fluid manipulation phenomena of rapidly growing significance in microfluidics, where the streaming often assumes the form of a steady, laminar jet emanating from the device surface, driven by the attenuation of acoustic energy within the beam of sound propagating through the liquid. The frequencies used to drive such phenomena are often chosen ad hoc to accommodate fabrication and material issues. In this work, we seek a better understanding of the effects of sound frequency and power on acoustic streaming. We present and, using surface acoustic waves, experimentally verify a laminar jet model that is based on the turbulent jet model of Lighthill, which is appropriate for acoustic streaming seen at micro- to nanoscales, between 20 and 936 MHz and over a broad range of input power. Our model eliminates the critically problematic acoustic source singularity present in Lighthill's model, replacing it with a finite emission area and enabling determination of the streaming velocity close to the source. At high acoustic power P (and hence high jet Reynolds numbers ReJ associated with fast streaming), the laminar jet model predicts a one-half power dependence (U∼P1/2∼ ReJ) similar to the turbulent jet model. However, the laminar model may also be applied to jets produced at low powers-and hence low jet Reynolds numbers ReJ-where a linear relationship between the beam power and streaming velocity exists: U∼P∼ReJ2. The ability of the laminar jet model to predict the acoustic streaming behavior across a broad range of frequencies and power provides a useful tool in the analysis of microfluidics devices, explaining peculiar observations made by several researchers in the literature. In particular, by elucidating the effects of frequency on the scale of acoustically driven flows, we show that the choice of frequency is a vitally important consideration in the design of small-scale devices employing acoustic streaming

  15. Mechanisms of change of a novel weight loss programme provided by a third sector organisation : a qualitative interview study.

    OpenAIRE

    McMahon, N.E.; Visram, S.; Connell, L.A.

    2016-01-01

    Background There is a need for theory-driven studies that explore the underlying mechanisms of change of complex weight loss programmes. Such studies will contribute to the existing evidence-base on how these programmes work and thus inform the future development and evaluation of tailored, effective interventions to tackle overweight and obesity. This study explored the mechanisms by which a novel weight loss programme triggered change amongst participants. The programme, delivered by a thir...

  16. ADS National Programmes: Germany

    International Nuclear Information System (INIS)

    The German R&D programme for ADS development is related to the partitioning and transmutation of spent fuel. This programme is implemented mainly by the three national research centres belonging to the Helmholtz Association, i.e. Karlsruhe Institute of Technology (KIT), Forschungszentrum Jülich (FZJ) in cooperation with the Technical University of Aachen (RWTH Aachen) and the Helmholtz Zentrum Dresden Rossendorf (HZDR). The main purpose of this R&D programme is the prospect to manage the high level radioactive waste such as to reduce the burden on a final repository. P&T does not eliminate the need for a final repository whatever the strategy, but it allows the reduction of the radio-toxicity associated with radioactive waste, the increase of the repository capacity as a consequence of the reduction of masses to be stored and their associated residual heat load. Different fuel cycle scenarios to implement P&T can be envisaged. These scenarios have been evaluated to identify the impact of P&T on the characteristics, number and deployment pace of the installations of the fuel cycle (reprocessing, fuel fabrication, storage etc). Almost all activities conducted in the R&D programme are embedded in European and international projects and initiatives. In the following more details on the relevant components of the R&D programme are summarized

  17. Springer handbook of acoustics

    CERN Document Server

    2014-01-01

    Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and electronics. The Springer Handbook of Acoustics is also in his 2nd edition an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents. This new edition of the Handbook features over 11 revised and expanded chapters, new illustrations, and 2 new chapters covering microphone arrays  and acoustic emission.  Updated chapters contain the latest research and applications in, e.g. sound propagation in the atmosphere, nonlinear acoustics in fluids, building and concert hall acoustics, signal processing, psychoacoustics, computer music, animal bioacousics, sound intensity, modal acoustics as well as new chapters on microphone arrays an...

  18. Vibro-acoustics

    CERN Document Server

    Nilsson, Anders

    2015-01-01

    This three-volume book gives a thorough and comprehensive presentation of vibration and acoustic theories. Different from traditional textbooks which typically deal with some aspects of either acoustic or vibration problems, it is unique of this book to combine those two correlated subjects together. Moreover, it provides fundamental analysis and mathematical descriptions for several crucial phenomena of Vibro-Acoustics which are quite useful in noise reduction, including how structures are excited, energy flows from an excitation point to a sound radiating surface, and finally how a structure radiates noise to a surrounding fluid. Many measurement results included in the text make the reading interesting and informative. Problems/questions are listed at the end of each chapter and the solutions are provided. This will help the readers to understand the topics of Vibro-Acoustics more deeply. The book should be of interest to anyone interested in sound and vibration, vehicle acoustics, ship acoustics and inter...

  19. External Mobility Programme

    CERN Multimedia

    HR Department

    2007-01-01

    Every year, a significant number of highly-skilled staff members leave the Organization and offer their talents on the European job market. CERN is launching a programme aiming to help staff members to whom the Organization cannot offer an indefinite contract in the transition towards their next employment. The programme, which is based on the establishment of a number of partnerships with potential employers in the private sector, will run on a voluntary basis. Staff members who have received confirmation that they will not be offered an indefinite contract and who are interested in availing themselves of the opportunities offered by the programme, are invited to enrol by following the procedure described at: https://ert.cern.ch/browse_intranet/wd_pds?p_web_page_id=5841 Applications will be processed in the strictest confidence by the Human Resources Department and eligible profiles will then be made available to partner companies for recruitment purposes. Any subsequent ...

  20. Punch Card Programmable Microfluidics

    CERN Document Server

    Korir, George

    2014-01-01

    Small volume fluid handling in single and multiphase microfluidics provides a promising strategy for efficient bio-chemical assays, low-cost point-of-care diagnostics and new approaches to scientific discoveries. However multiple barriers exist towards low-cost field deployment of programmable microfluidics. Incorporating multiple pumps, mixers and discrete valve based control of nanoliter fluids and droplets in an integrated, programmable manner without additional required external components has remained elusive. Combining the idea of punch card programming with arbitrary fluid control, here we describe a self-contained, hand-crank powered, multiplex and robust programmable microfluidic platform. A paper tape encodes information as a series of punched holes. A mechanical reader/actuator reads these paper tapes and correspondingly executes a series of operations onto a microfluidic chip coupled to the platform in a plug-and-play fashion. Enabled by the complexity of codes that can be represented by a series ...

  1. Funktionell Programmering : En framtidsprognos

    OpenAIRE

    Holmer, Mattias

    2011-01-01

    Trenden inom systemutveckling och programutveckling går mot ett mer användande av multi programmeringsparadigmer. Funktionell programmering har fått mer uppmärksamhet på senare tid och utvecklingen tycks över lag gå än mer åt det deklarativa hållet där programmeraren fokuserar mer på vad som skall utföras och inte lika mycket på hur. Under en tid har det objektorienterade paradigmet varit dominerande, kommer det vara så i framtiden? Funktionell programmering skiljer sig från imperativ program...

  2. Computer mathematics for programmers

    CERN Document Server

    Abney, Darrell H; Sibrel, Donald W

    1985-01-01

    Computer Mathematics for Programmers presents the Mathematics that is essential to the computer programmer.The book is comprised of 10 chapters. The first chapter introduces several computer number systems. Chapter 2 shows how to perform arithmetic operations using the number systems introduced in Chapter 1. The third chapter covers the way numbers are stored in computers, how the computer performs arithmetic on real numbers and integers, and how round-off errors are generated in computer programs. Chapter 4 details the use of algorithms and flowcharting as problem-solving tools for computer p

  3. A programmer's geometry

    CERN Document Server

    Bowyer, Adrian

    1983-01-01

    A Programmer's Geometry provides a guide in programming geometric shapes. The book presents formulas and examples of computer representation and coding of geometry. Each of the nine chapters of the text deals with the representation and solution of a specific geometrical problem, such as areas, vectors, and volumes. The last chapter provides a brief discussion on generating image through a computer. The codes presented in the book are written in FORTRAN 77. The text will be of great use to programmers who are working on projects that involve geometric calculations.

  4. Shallow Water Acoustic Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Supports experimental research where high-frequency acoustic scattering and surface vibration measurements of fluid-loaded and non-fluid-loaded structures...

  5. Low frequency acoustic microscope

    Science.gov (United States)

    Khuri-Yakub, Butrus T.

    1986-11-04

    A scanning acoustic microscope is disclosed for the detection and location of near surface flaws, inclusions or voids in a solid sample material. A focused beam of acoustic energy is directed at the sample with its focal plane at the subsurface flaw, inclusion or void location. The sample is scanned with the beam. Detected acoustic energy specularly reflected and mode converted at the surface of the sample and acoustic energy reflected by subsurface flaws, inclusions or voids at the focal plane are used for generating an interference signal which is processed and forms a signal indicative of the subsurface flaws, inclusions or voids.

  6. Handbook of Engineering Acoustics

    CERN Document Server

    Möser, Michael

    2013-01-01

    This book examines the physical background of engineering acoustics, focusing on empirically obtained engineering experience as well as on measurement techniques and engineering methods for prognostics. Its goal is not only to describe the state of art of engineering acoustics but also to give practical help to engineers in order to solve acoustic problems. It deals with the origin, the transmission and the methods of the abating different kinds of air-borne and structure-borne sounds caused by various mechanisms – from traffic to machinery and flow-induced sound. In addition the modern aspects of room and building acoustics, as well as psychoacoustics and active noise control, are covered.

  7. Localized acoustic surface modes

    Science.gov (United States)

    Farhat, Mohamed; Chen, Pai-Yen; Bağcı, Hakan

    2016-04-01

    We introduce the concept of localized acoustic surface modes. We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  8. Localized Acoustic Surface Modes

    KAUST Repository

    Farhat, Mohamed

    2015-08-04

    We introduce the concept of localized acoustic surface modes (ASMs). We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  9. What Is an Acoustic Neuroma

    Science.gov (United States)

    ... org Connect with us! What is an Acoustic Neuroma? Each heading slides to reveal information. Important Points ... Neuroma Important Points To Know About an Acoustic Neuroma An acoustic neuroma, also called a vestibular schwannoma, ...

  10. Mexican medfly programme

    International Nuclear Information System (INIS)

    This film tells the story of the fight against and final extinction of the Mediterranean fruit-fly (Ceratitis capitata) in Mexico. By producing billions of high quality sterile flies in the Medfly reproduction and sterilization laboratory in the province of Chiapas and releasing them over infested areas, the Moscamed Programme succeeded in eradicating this pest from Mexico in 1982

  11. Kulturalistische Unternehmensethik : ein Programm

    OpenAIRE

    Hanekamp, Gerd

    2001-01-01

    "Das Programm einer kulturalistischen Unternehmensethik wird vorgestellt. Es gründet auf einem philosophischen Ansatz, der sich als instrumentalistisch, kontextualistisch, transsubjektivistisch und individualistisch charakterisieren lässt. Hinsichtlich der ethischen Grundlagen werden starke Thesen durch den Rekurs auf eine kontextualistisch-normative Anthropologie vermieden." (Autorenreferat)

  12. SET-Routes programme

    CERN Multimedia

    Marietta Schupp, EMBL Photolab

    2008-01-01

    Dr Sabine Hentze, specialist in human genetics, giving an Insight Lecture entitled "Human Genetics – Diagnostics, Indications and Ethical Issues" on 23 September 2008 at EMBL Heidelberg. Activities in a achool in Budapest during a visit of Angela Bekesi, Ambassadors for the SET-Routes programme.

  13. The European Programme Manager

    DEFF Research Database (Denmark)

    Larson, Anne; Bergman, E.; Ehlers, S.;

    The publication is a result of a cooperation between organisations in six European countries with the aim to develop a common European education for programme managers. It contains of a description of the different elements of the education together with a number of case-studies from the counties...

  14. Fusion technology programme

    International Nuclear Information System (INIS)

    KfK is involved in the European Fusion Programme predominantly in the NET and Fusion Technology part. The following fields of activity are covered: Studies for NET, alternative confinement concepts, and needs and issues of integral testing. Research on structural materials. Development of superconducting magnets. Gyrotron development (part of the Physics Programme). Nuclear technology (breeding materials, blanket design, tritium technology, safety and environmental aspects of fusion, remote maintenance). Reported here are status and results of work under contracts with the CEC within the NET and Technology Programme. The aim of the major part of this R and D work is the support of NET, some areas (e.g. materials, safety and environmental impact, blanket design) have a wider scope and address problems of a demonstration reactor. In the current working period, several new proposals have been elaborated to be implemented into the 85/89 Euratom Fusion Programme. New KfK contributions relate to materials research (dual beam and fast reactor irradiations, ferritic steels), to blanket engineering (MHD-effects) and to safety studies (e.g. magnet safety). (orig./GG)

  15. Air Quality Monitoring Programme

    DEFF Research Database (Denmark)

    Kemp, K.; Palmgren, F.

    The Danish Air Quality Monitoring Programme (LMP IV) has been revised in accordance with the Framework Directive and the first three daughter directives of SO2, NOx/NO2, PM10, lead, benzene, CO and ozone. PM10 samplers are under installation and the installation will be completed during 2002...

  16. Progressive Retirement Programme

    CERN Multimedia

    HR Department

    2007-01-01

    Following discussion at the Standing Concertation Committee at its meeting on 30 January 2007, the Director-General has approved the extension of the Progressive Retirement Programme with effect from 1 April 2007 until 31 March 2008. Human Resources Department Tel. 74484/74128

  17. Fast reactor programme

    International Nuclear Information System (INIS)

    This progress report summarises the fast reactor research carried out at the Netherlands Energy Research Centre during the year 1981. The neutron and fission product cross sections of various isotopes have been evaluated. In the fuel performance programme, some preliminary results are given and irradiation facilities described. Creep experiments on various stainless steel components are reported

  18. En model for programmer

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    Dette undervisningsmateriale beskriver en model for, hvordan programmer er opbygget. Materialet er skrevet til brug i det gymnasiale forsøgsfag Informationsteknologi. Seneste version af dette undervisningsmateriale kan findes på http:// www.imhotep.dk. Tak til Elisabeth Husum for en kritisk...

  19. Piezoelectrically-driven Thermoacoustic Refrigerator

    Science.gov (United States)

    Chinn, Daniel George

    Thermoacoustic refrigeration is an emerging refrigeration technology which does not require any moving parts or harmful refrigerants in its operation. This technology uses acoustic waves to pump heat across a temperature gradient. The vast majority of thermoacoustic refrigerators to date have used electromagnetic loudspeakers to generate the acoustic input. In this thesis, the design, construction, operation, and modeling of a piezoelectrically-driven thermoacoustic refrigerator are detailed. This refrigerator demonstrates the effectiveness of piezoelectric actuation in moving 0.3 W of heat across an 18 degree C temperature difference with an input power of 7.6 W. The performance characteristics of this class of thermoacoustic-piezoelectric refrigerators are modeled by using DeltaEC software and the predictions are experimentally validated. The obtained results confirm the validity of the developed model. Furthermore, the potential of piezoelectric actuation as effective means for driving thermoacoustic refrigerators is demonstrated as compared to the conventional electromagnetic loudspeakers which are heavy and require high actuation energy. The developed theoretical and experimental tools can serve as invaluable means for the design and testing of other piezoelectrically-driven thermoacoustic refrigerator configurations.

  20. Predicting Acoustics in Class Rooms

    DEFF Research Database (Denmark)

    Christensen, Claus Lynge; Rindel, Jens Holger

    2005-01-01

    Typical class rooms have fairly simple geometries, even so room acoustics in this type of room is difficult to predict using today's room acoustic computer modeling software. The reasons why acoustics of class rooms are harder to predict than acoustics of complicated concert halls might be explai......Typical class rooms have fairly simple geometries, even so room acoustics in this type of room is difficult to predict using today's room acoustic computer modeling software. The reasons why acoustics of class rooms are harder to predict than acoustics of complicated concert halls might...... with surface scattering is presented. Each of the two scattering effects is modeled as frequency dependent functions....

  1. ADS National Programmes: Russian Federation

    International Nuclear Information System (INIS)

    Studies on accelerator driven systems (ADS), which be used as burners of long lived radioactive waste accrued due to operation of thermal reactors, first of all, minor actinides (MA), are carried out in some Russian research institutes (ITEP, SSC RF - IPPE, VNIIEF, JINR, RSC KI, IYaI RAN, OKB ‘GIDROPRESS’, VNIITF etc.). These researches are mainly connected with studying physical processes existing in ADS and their parameters and with design studies and substantiation of experimental ADS facilities. One of the most important directions of researches is the acquirement of quite precise and reliable nuclear data on MA with reference to conditions existing in ADS. Now a coordinated programme of researches on measurement and estimation of nuclear data for 22 isotopes of U, Pu, Np, Am, Cm, Bk and Cf in neutron energy range from 0.05 eV up to 30 MeV has been prepared. Development of different variants of ADS has put a task of comparison of their efficiency as burners of MA

  2. Ocean acoustic reverberation tomography.

    Science.gov (United States)

    Dunn, Robert A

    2015-12-01

    Seismic wide-angle imaging using ship-towed acoustic sources and networks of ocean bottom seismographs is a common technique for exploring earth structure beneath the oceans. In these studies, the recorded data are dominated by acoustic waves propagating as reverberations in the water column. For surveys with a small receiver spacing (e.g., ocean acoustic reverberation tomography, is developed that uses the travel times of direct and reflected waves to image ocean acoustic structure. Reverberation tomography offers an alternative approach for determining the structure of the oceans and advancing the understanding of ocean heat content and mixing processes. The technique has the potential for revealing small-scale ocean thermal structure over the entire vertical height of the water column and along long survey profiles or across three-dimensional volumes of the ocean. For realistic experimental geometries and data noise levels, the method can produce images of ocean sound speed on a smaller scale than traditional acoustic tomography.

  3. Acoustic Signals and Systems

    DEFF Research Database (Denmark)

    2008-01-01

    The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook...... will present topics on signal processing which are important in a specific area of acoustics. These will be of interest to specialists in these areas because they will be presented from their technical perspective, rather than a generic engineering approach to signal processing. Non-specialists, or specialists...... from different areas, will find the self-contained chapters accessible and will be interested in the similarities and differences between the approaches and techniques used in different areas of acoustics....

  4. Ocean acoustic hurricane classification.

    Science.gov (United States)

    Wilson, Joshua D; Makris, Nicholas C

    2006-01-01

    Theoretical and empirical evidence are combined to show that underwater acoustic sensing techniques may be valuable for measuring the wind speed and determining the destructive power of a hurricane. This is done by first developing a model for the acoustic intensity and mutual intensity in an ocean waveguide due to a hurricane and then determining the relationship between local wind speed and underwater acoustic intensity. From this it is shown that it should be feasible to accurately measure the local wind speed and classify the destructive power of a hurricane if its eye wall passes directly over a single underwater acoustic sensor. The potential advantages and disadvantages of the proposed acoustic method are weighed against those of currently employed techniques. PMID:16454274

  5. Cochlear bionic acoustic metamaterials

    Science.gov (United States)

    Ma, Fuyin; Wu, Jiu Hui; Huang, Meng; Fu, Gang; Bai, Changan

    2014-11-01

    A design of bionic acoustic metamaterial and acoustic functional devices was proposed by employing the mammalian cochlear as a prototype. First, combined with the experimental data in previous literatures, it is pointed out that the cochlear hair cells and stereocilia cluster are a kind of natural biological acoustic metamaterials with the negative stiffness characteristics. Then, to design the acoustic functional devices conveniently in engineering application, a simplified parametric helical structure was proposed to replace actual irregular cochlea for bionic design, and based on the computational results of such a bionic parametric helical structure, it is suggested that the overall cochlear is a local resonant system with the negative dynamic effective mass characteristics. There are many potential applications in the bandboard energy recovery device, cochlear implant, and acoustic black hole.

  6. Computational Ocean Acoustics

    CERN Document Server

    Jensen, Finn B; Porter, Michael B; Schmidt, Henrik

    2011-01-01

    Since the mid-1970s, the computer has played an increasingly pivotal role in the field of ocean acoustics. Faster and less expensive than actual ocean experiments, and capable of accommodating the full complexity of the acoustic problem, numerical models are now standard research tools in ocean laboratories. The progress made in computational ocean acoustics over the last thirty years is summed up in this authoritative and innovatively illustrated new text. Written by some of the field's pioneers, all Fellows of the Acoustical Society of America, Computational Ocean Acoustics presents the latest numerical techniques for solving the wave equation in heterogeneous fluid–solid media. The authors discuss various computational schemes in detail, emphasizing the importance of theoretical foundations that lead directly to numerical implementations for real ocean environments. To further clarify the presentation, the fundamental propagation features of the techniques are illustrated in color. Computational Ocean A...

  7. Electrically Driven Technologies for Radioactive Aerosol Abatement

    Energy Technology Data Exchange (ETDEWEB)

    David W. DePaoli; Ofodike A. Ezekoye; Costas Tsouris; Valmor F. de Almeida

    2003-01-28

    The purpose of this research project was to develop an improved understanding of how electriexecy driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume.

  8. Aurora europe's space exploration programme

    Science.gov (United States)

    Ongaro, F.; Swings, J. P.; Condessa, R.

    2003-04-01

    What will happen after the ISS in terms of space exploration, specifically to the human presence beyond Earth? What will be the role of Europe in the future international venture to explore space? What are the most immediate actions to be undertaken in Europe in order to best profit from the efforts made through the participation in the ISS and to position Europe's capabilities according to its interests? As approved by the Ministers at the Edinburgh Council in November 2001, the European Space Exploration Programme - Aurora - is ESA's programme in charge of defining and implementing the long term plan for human and robotic exploration of the Solar system. The Aurora programme started in 2002 and extends until the end goal of Aurora: the first human mission to Mars, expected in the 2025-2030 time-frame. The approach of Aurora is to implement a robust development of technologies and robotic missions, in parallel to the utilization phase of the ISS, to prepare for a continuous and sustainable future of human space exploration (which shall include the Moon, Mars and the asteroids as targets), in which Europe will be a valuable partner. Two classes of missions are foreseen in the programme's strategy: Flagships, defined as major missions driving to soft landing, in-situ analysis, sample return from other planetary bodies and eventually human missions; and Arrows, defined as cost-capped, short development time missions to demonstrate new technologies or mission approaches, or to exploit opportunities for payloads on European or international missions. So far the participating national delegations have approved two Flagships (ExoMars and Mars Sample Return) and two Arrows (Earth Re-entry and Mars Aerocapture) for phase A industrial studies. Although the last call for ideas of Aurora resulted in the definition of two Flagship missions targeted to Mars, the next one might be aimed to the Moon. At this stage the role of the Moon, on the path of Mars exploration is not

  9. Donor transplant programme

    International Nuclear Information System (INIS)

    The transplantation of organs and tissues from one human to another human has become an essential and well established form of therapy for many types of organ and tissue failure. In Malaysia, kidney, cornea and bone marrow transplantation are well established. Recently, liver, bone and heart transplanation have been performed. Unfortunately, because of the lack of cadaveric organ donation, only a limited number of solid organ transplantation have been performed. The cadaveric organ donor rate in Malaysia is low at less than one per million population. The first tissue transplanted in Malaysia was the cornea which was performed in the early 1970s. At that time and even now the majority of corneas came from Sri Lanka. The first kidney transplant was performed in 1975 from a live related donor. The majority of the 629 kidney transplants done at Hospital Kuala Lumpur to date have been from live related donors. Only 35 were from cadaver donors. Similarly, the liver transplantation programme which started in 1995 are from live related donors. A more concerted effort has been made recently to increase the awareness of the public and the health professionals on organ and tissue donation. This national effort to promote organ and tissue donation seems to have gathered momentum in 1997 with the first heart transplant successfully performed at the National Heart Institute. The rate of cadaveric donors has also increased from a previous average of I to 2 per year to 6 per year in the last one year. These developments are most encouraging and may signal the coming of age of our transplantati on programme. The Ministry of Health in conjunction with various institutions, organizations and professional groups, have taken a number of proactive measures to facilitate the development of the cadaveric organ donation programme. Efforts to increase public awareness and to overcome the negative cultural attitude towards organ donation have been intensified. Equally important are efforts

  10. The INTEGRAL Core Observing Programme

    DEFF Research Database (Denmark)

    Winkler, C.; Gehrels, N.; Lund, Niels;

    1999-01-01

    The Core Programme of the INTEGRAL mission is defined as the portion of the scientific programme covering the guaranteed time observations for the INTEGRAL Science Working Team. This paper describes the current status of the Core Programme preparations and summarizes the key elements...

  11. Laser Imaging of Airborne Acoustic Emission by Nonlinear Defects

    Science.gov (United States)

    Solodov, Igor; Döring, Daniel; Busse, Gerd

    2008-06-01

    Strongly nonlinear vibrations of near-surface fractured defects driven by an elastic wave radiate acoustic energy into adjacent air in a wide frequency range. The variations of pressure in the emitted airborne waves change the refractive index of air thus providing an acoustooptic interaction with a collimated laser beam. Such an air-coupled vibrometry (ACV) is proposed for detecting and imaging of acoustic radiation of nonlinear spectral components by cracked defects. The photoelastic relation in air is used to derive induced phase modulation of laser light in the heterodyne interferometer setup. The sensitivity of the scanning ACV to different spatial components of the acoustic radiation is analyzed. The animated airborne emission patterns are visualized for the higher harmonic and frequency mixing fields radiated by planar defects. The results confirm a high localization of the nonlinear acoustic emission around the defects and complicated directivity patterns appreciably different from those observed for fundamental frequencies.

  12. Bioergia Research Programme

    International Nuclear Information System (INIS)

    The main objectives of Finland's Bioenergia Research Programme are (1) To develop new methods of producing biofuels which can compete with imported fuels, demonstrating the most promising production methods through pilot schemes, (2) To develop and demonstrate 3 - 4 new pieces of equipment or methods connected with handling and using bioenergy, (3) To produce basic information on conversion techniques and evaluate the quality, usability and environmental impacts of the products as well as the overall economy of the entire production chain and to create 2-3 conversion methods for follow-up development by industry. The principle research areas are (1) Development of production technology for wood-derived fuels, (2) Peat production, (3) The use of bioenergy and (4) Biomass conversion. This conference paper discusses the results obtained so far and reviews in some detail the activities of the programme. 3 figs., 3 tabs

  13. Bioergia Research Programme

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, D.

    1997-12-31

    The main objectives of Finland`s Bioenergia Research Programme are (1) To develop new methods of producing biofuels which can compete with imported fuels, demonstrating the most promising production methods through pilot schemes, (2) To develop and demonstrate 3 - 4 new pieces of equipment or methods connected with handling and using bioenergy, (3) To produce basic information on conversion techniques and evaluate the quality, usability and environmental impacts of the products as well as the overall economy of the entire production chain and to create 2-3 conversion methods for follow-up development by industry. The principle research areas are (1) Development of production technology for wood-derived fuels, (2) Peat production, (3) The use of bioenergy and (4) Biomass conversion. This conference paper discusses the results obtained so far and reviews in some detail the activities of the programme. 3 figs., 3 tabs.

  14. Fusion technology programme

    International Nuclear Information System (INIS)

    The KfK-Association has continued work on 17 R and D contracts of the Fusion Technology Programme. An effort of 94 manyears per year is at present contributed by 10 KfK departments, covering all aereas defined in the Fusion Technology Programme. The dominant part of the work is directed towards the need of the NET design or supporting experiments. Some additional effort addresses long term technological issues and system studies relevant to DEMO or confinement schemes alternative to tokamaks. Direct contribution to the NET team has increased by augmentation of NET study contracts and delegation of personnel, three KfK delegates being at present members of the NET team. In reverse, specifications and design guidelines worked out by NET have started to have an impact on the current R and D-work in the laboratory. (orig./GG)

  15. Pharmacovigilance programme of India

    Directory of Open Access Journals (Sweden)

    Kalaiselvan Vivekanandan

    2012-01-01

    Full Text Available The monitoring and reporting of adverse drug reactions (ADRs through pharmacovigilance is vital to patient safety and rational prescribing. In India, Central Drugs Standard Control Organization (CDSCO initiated Pharmacovigilance Programme of India (PvPI to report ADRs through ADRs monitoring centres in India. Indian Pharmacopoeia Commission (IPC is functioning as National Coordination Centre (NCC for PvPI. The ADRs are reported to NCC through VigiFlow by various centres are evaluated and committed to Uppsala Monitoring Centre, Sweden. The potential benefit of the PvPI is aimed to reducing or eliminating a harm of medicine. Continuous efforts of the healthcare professionals and the patients are expected to make this as one of the most successful and effective programmes. The present article updates the status and future plan of PvPI.

  16. Flat acoustic lens by acoustic grating with curled slits

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Pai; Xiao, Bingmu; Wu, Ying, E-mail: ying.wu@kaust.edu.sa

    2014-10-03

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry–Perot resonance. - Highlights: • Expression of transmission coefficient of an acoustic grating with curled slits. • Non-dispersive and tunable effective medium parameters for the acoustic grating. • A flat acoustic focusing lens with gradient index by using the acoustic grating.

  17. Evaluation of the Community Group Programme for Children & Young People: final report

    OpenAIRE

    Nolas, Sevasti-Melissa; Neville, Lucy; Sanders-McDonagh, Erin

    2012-01-01

    The report presents findings from the evaluation of the Community Group Programme (CGP). The CGP is a 12-week psycho-educational, group work programme for children and young people who have experienced domestic violence. The Programme was developed in Canada and is being rolled out in England for the first time across 32 London boroughs. The programme is unique in working with children and their mothers concurrently and in a child-focused way. The study takes a theory-driven approach to evalu...

  18. The Mathematica programmer

    CERN Document Server

    Maeder, Roman E

    1994-01-01

    The Mathematica Programmer covers the fundamental programming paradigms and applications of programming languages. This book is organized into two parts encompassing 10 chapters. Part 1 begins with an overview of the programming paradigms. This part also treats abstract data types, polymorphism and message passing, object-oriented programming, and relational databases. Part 2 looks into the practical aspects of programming languages, including in lists and power series, fractal curves, and minimal surfaces.This book will prove useful to mathematicians and computer scientists.

  19. Programmable mechanical metamaterials.

    Science.gov (United States)

    Florijn, Bastiaan; Coulais, Corentin; van Hecke, Martin

    2014-10-24

    We create mechanical metamaterials whose response to uniaxial compression can be programmed by lateral confinement, allowing monotonic, nonmonotonic, and hysteretic behavior. These functionalities arise from a broken rotational symmetry which causes highly nonlinear coupling of deformations along the two primary axes of these metamaterials. We introduce a soft mechanism model which captures the programmable mechanics, and outline a general design strategy for confined mechanical metamaterials. Finally, we show how inhomogeneous confinement can be explored to create multistability and giant hysteresis.

  20. ADS National Programmes: Italy

    International Nuclear Information System (INIS)

    Following a preliminary design developed in 1998, based on the Energy Amplifier concept proposed by CERN, a first configuration of a lead-bismuth Eutectic cooled Experimental ADS (LBE-XADS) was worked out in the period 1999–2001, under the aegis of MURST, by a group of Italian organizations led by Ansado Nucleare, with the aim of assessing the feasibility of a small sized (80 MWth) ADS. At the end of 1997 a joint effort of ENEA (National Agency for New Technology, Energy and the Environment) and INFN (National Institute for Nuclear Physics) led to the approval of a national programme by MURST (Minister for University and Scientific and Technological Research) named TRASCO (TRAsmutazione SCOrie) aiming at the study of physics and technologies needed to design an ADS for radioactive waste transmutation. The programme consisted of research subprogrammes on accelerator, neutronics, thermalhydraulics analysis, beam window technology, and material technology and compatibility with Pb and Pb-Bi. At now, most of the activities in support to the ADS development carried out at national level are part of EU-funded Projects. These activities are complemented by the programme agreement (AdP -Accordo di programma), signed between ENEA and the Ministry of Economic Development, which provides in general a range of activities aimed at the development of sustainable nuclear fission systems. Several universities and the national industry are involved, besides ENEA, in the activities

  1. Programmable Quantitative DNA Nanothermometers.

    Science.gov (United States)

    Gareau, David; Desrosiers, Arnaud; Vallée-Bélisle, Alexis

    2016-07-13

    Developing molecules, switches, probes or nanomaterials that are able to respond to specific temperature changes should prove of utility for several applications in nanotechnology. Here, we describe bioinspired strategies to design DNA thermoswitches with programmable linear response ranges that can provide either a precise ultrasensitive response over a desired, small temperature interval (±0.05 °C) or an extended linear response over a wide temperature range (e.g., from 25 to 90 °C). Using structural modifications or inexpensive DNA stabilizers, we show that we can tune the transition midpoints of DNA thermometers from 30 to 85 °C. Using multimeric switch architectures, we are able to create ultrasensitive thermometers that display large quantitative fluorescence gains within small temperature variation (e.g., > 700% over 10 °C). Using a combination of thermoswitches of different stabilities or a mix of stabilizers of various strengths, we can create extended thermometers that respond linearly up to 50 °C in temperature range. Here, we demonstrate the reversibility, robustness, and efficiency of these programmable DNA thermometers by monitoring temperature change inside individual wells during polymerase chain reactions. We discuss the potential applications of these programmable DNA thermoswitches in various nanotechnology fields including cell imaging, nanofluidics, nanomedecine, nanoelectronics, nanomaterial, and synthetic biology. PMID:27058370

  2. A new video programme

    CERN Multimedia

    CERN video productions

    2011-01-01

    "What's new @ CERN?", a new monthly video programme, will be broadcast on the Monday of every month on webcast.cern.ch. Aimed at the general public, the programme will cover the latest CERN news, with guests and explanatory features. Tune in on Monday 3 October at 4 pm (CET) to see the programme in English, and then at 4:20 pm (CET) for the French version.   var flash_video_player=get_video_player_path(); insert_player_for_external('Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-0753-kbps-640x360-25-fps-audio-64-kbps-44-kHz-stereo', 'mms://mediastream.cern.ch/MediaArchive/Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-Multirate-200-to-753-kbps-640x360-25-fps.wmv', 'false', 480, 360, 'https://mediastream.cern.ch/MediaArchive/Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-posterframe-640x360-at-10-percent.jpg', '1383406', true, 'Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-0600-kbps-maxH-360-25-fps-...

  3. Acoustic mapping velocimetry

    Science.gov (United States)

    Muste, M.; Baranya, S.; Tsubaki, R.; Kim, D.; Ho, H.; Tsai, H.; Law, D.

    2016-05-01

    Knowledge of sediment dynamics in rivers is of great importance for various practical purposes. Despite its high relevance in riverine environment processes, the monitoring of sediment rates remains a major and challenging task for both suspended and bed load estimation. While the measurement of suspended load is currently an active area of testing with nonintrusive technologies (optical and acoustic), bed load measurement does not mark a similar progress. This paper describes an innovative combination of measurement techniques and analysis protocols that establishes the proof-of-concept for a promising technique, labeled herein Acoustic Mapping Velocimetry (AMV). The technique estimates bed load rates in rivers developing bed forms using a nonintrusive measurements approach. The raw information for AMV is collected with acoustic multibeam technology that in turn provides maps of the bathymetry over longitudinal swaths. As long as the acoustic maps can be acquired relatively quickly and the repetition rate for the mapping is commensurate with the movement of the bed forms, successive acoustic maps capture the progression of the bed form movement. Two-dimensional velocity maps associated with the bed form migration are obtained by implementing algorithms typically used in particle image velocimetry to acoustic maps converted in gray-level images. Furthermore, use of the obtained acoustic and velocity maps in conjunction with analytical formulations (e.g., Exner equation) enables estimation of multidirectional bed load rates over the whole imaged area. This paper presents a validation study of the AMV technique using a set of laboratory experiments.

  4. Acoustic sniper localization system

    Science.gov (United States)

    Prado, Gervasio; Dhaliwal, Hardave; Martel, Philip O.

    1997-02-01

    Technologies for sniper localization have received increased attention in recent months as American forces have been deployed to various trouble spots around the world. Among the technologies considered for this task acoustics is a natural choice for various reasons. The acoustic signatures of gunshots are loud and distinctive, making them easy to detect even in high noise background environments. Acoustics provides a passive sensing technology with excellent range and non line of sight capabilities. Last but not least, an acoustic sniper location system can be built at a low cost with off the shelf components. Despite its many advantages, the performance of acoustic sensors can degrade under adverse propagation conditions. Localization accuracy, although good, is usually not accurate enough to pinpoint a sniper's location in some scenarios (for example which widow in a building or behind which tree in a grove). For these more demanding missions, the acoustic sensor can be used in conjunction with an infra red imaging system that detects the muzzle blast of the gun. The acoustic system can be used to cue the pointing system of the IR camera in the direction of the shot's source.

  5. Underwater Applications of Acoustical Holography

    Directory of Open Access Journals (Sweden)

    P. C. Mehta

    1984-01-01

    Full Text Available The paper describes the basic technique of acoustical holography. Requirements for recording the acoustical hologram are discussed with its ability for underwater imaging in view. Some practical systems for short-range and medium-range imaging are described. The advantages of acoustical holography over optical imaging, acoustical imaging and sonars are outlined.

  6. ESF EUROCORES Programmes In Geosciences And Environmental Sciences

    Science.gov (United States)

    Jonckheere, I. G.

    2007-12-01

    In close cooperation with its Member Organisations, the European Science Foundation (ESF) has launched since late 2003 a series of European Collaborative Research (EUROCORES) Programmes. Their aim is to enable researchers in different European countries to develop cooperation and scientific synergy in areas where European scale and scope are required in a global context. The EUROCORES Scheme provides an open, flexible and transparent framework that allows national science funding and science performing agencies to join forces to support excellent European-led research, following a selection among many science-driven suggestions for new Programmes themes submitted by the scientific community. The EUROCORES instrument represents the first large scale attempt of national research (funding) agencies to act together against fragmentation, asynchronicity and duplication of research (funding) within Europe. There are presently 7 EUROCORES Programmes specifically dealing with cutting edge science in the fields of Earth, Climate and Environmental Sciences. The EUROCORES Programmes consist of a number of international, multidisciplinary collaborative research projects running for 3-4 years, selected through independent peer review. Under the overall responsibility of the participating funding agencies, those projects are coordinated and networked together through the scientific guidance of a Scientific Committee, with the support of a Programme Coordinator, responsible at ESF for providing planning, logistics, and the integration and dissemination of science. Strong links are aimed for with other major international programmes and initiatives worldwide. In this framework, linkage to IYPE would be of major interest for the scientific communities involved. Each Programme mobilises 5 to 13 million Euros in direct science funding from 9 to 27 national agencies from 8 to 20 countries. Additional funding for coordination, networking and dissemination is allocated by the ESF

  7. Ocean acoustic reverberation tomography.

    Science.gov (United States)

    Dunn, Robert A

    2015-12-01

    Seismic wide-angle imaging using ship-towed acoustic sources and networks of ocean bottom seismographs is a common technique for exploring earth structure beneath the oceans. In these studies, the recorded data are dominated by acoustic waves propagating as reverberations in the water column. For surveys with a small receiver spacing (e.g., tomography, is developed that uses the travel times of direct and reflected waves to image ocean acoustic structure. Reverberation tomography offers an alternative approach for determining the structure of the oceans and advancing the understanding of ocean heat content and mixing processes. The technique has the potential for revealing small-scale ocean thermal structure over the entire vertical height of the water column and along long survey profiles or across three-dimensional volumes of the ocean. For realistic experimental geometries and data noise levels, the method can produce images of ocean sound speed on a smaller scale than traditional acoustic tomography. PMID:26723303

  8. Acoustic integrated extinction

    CERN Document Server

    Norris, Andrew N

    2015-01-01

    The integrated extinction (IE) is defined as the integral of the scattering cross-section as a function of wavelength. Sohl et al. [1] derived an IE expression for acoustic scattering that is causal, i.e. the scattered wavefront in the forward direction arrives later than the incident plane wave in the background medium. The IE formula was based on electromagnetic results, for which scattering is causal by default. Here we derive a formula for the acoustic IE that is valid for causal and non-causal scattering. The general result is expressed as an integral of the time dependent forward scattering function. The IE reduces to a finite integral for scatterers with zero long-wavelength monopole and dipole amplitudes. Implications for acoustic cloaking are discussed and a new metric is proposed for broadband acoustic transparency.

  9. Autonomous Acoustic Receiver System

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Collects underwater acoustic data and oceanographic data. Data are recorded onboard an ocean buoy and can be telemetered to a remote ship or shore station...

  10. Thermal Acoustic Fatigue Apparatus

    Data.gov (United States)

    Federal Laboratory Consortium — The Thermal Acoustic Fatigue Apparatus (TAFA) is a progressive wave tube test facility that is used to test structures for dynamic response and sonic fatigue due to...

  11. Acoustic Igniter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An acoustic igniter eliminates the need to use electrical energy to drive spark systems to initiate combustion in liquid-propellant rockets. It does not involve the...

  12. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... treatment Summary Types Of Post-treatment Issues Resources Medical Resources Considerations When Selecting a Healthcare Professional Healthcare ... ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic Neuroma ...

  13. Acoustics lecturing in Mexico

    Science.gov (United States)

    Beristain, Sergio

    2002-11-01

    Some thirty years ago acoustics lecturing started in Mexico at the National Polytechnic Institute in Mexico City, as part of the Bachelor of Science degree in Communications and Electronics Engineering curricula, including the widest program on this field in the whole country. This program has been producing acoustics specialists ever since. Nowadays many universities and superior education institutions around the country are teaching students at the B.Sc. level and postgraduate level many topics related to acoustics, such as Architectural Acoustics, Seismology, Mechanical Vibrations, Noise Control, Audio, Audiology, Music, etc. Also many institutions have started research programs in related fields, with participation of medical doctors, psychologists, musicians, engineers, etc. Details will be given on particular topics and development.

  14. An acoustic invisible gateway

    CERN Document Server

    Zhu, Yi-Fan; Liang, Bin; Kan, Wei-Wei; Yang, Jun; Cheng, Jian-Chun

    2015-01-01

    The recently-emerged concept of "invisible gateway" with the extraordinary capability to block the waves but allow the passage of other entities has attracted great attentions due to the general interests in illusion devices. However, the possibility to realize such a fascinating phenomenon for acoustic waves has not yet been explored, which should be of paramount significance for acoustical applications but would necessarily involve experimental difficulty. Here we design and experimentally demonstrate an acoustic invisible gateway (AIG) capable of concealing a channel under the detection of sound. Instead of "restoring" a whole block of background medium by using transformation acoustics that inevitably requires complementary or restoring media with extreme parameters, we propose an inherently distinct methodology that only aims at engineering the surface impedance at the "gate" to mimic a rigid "wall" and can be conveniently implemented by decorating meta-structures behind the channel. Such a simple yet ef...

  15. Principles of musical acoustics

    CERN Document Server

    Hartmann, William M

    2013-01-01

    Principles of Musical Acoustics focuses on the basic principles in the science and technology of music. Musical examples and specific musical instruments demonstrate the principles. The book begins with a study of vibrations and waves, in that order. These topics constitute the basic physical properties of sound, one of two pillars supporting the science of musical acoustics. The second pillar is the human element, the physiological and psychological aspects of acoustical science. The perceptual topics include loudness, pitch, tone color, and localization of sound. With these two pillars in place, it is possible to go in a variety of directions. The book treats in turn, the topics of room acoustics, audio both analog and digital, broadcasting, and speech. It ends with chapters on the traditional musical instruments, organized by family. The mathematical level of this book assumes that the reader is familiar with elementary algebra. Trigonometric functions, logarithms and powers also appear in the book, but co...

  16. Anal acoustic reflectometry

    DEFF Research Database (Denmark)

    Mitchell, Peter J; Klarskov, Niels; Telford, Karen J;

    2011-01-01

    Anal acoustic reflectometry is a new technique of assessing anal sphincter function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, the opening and closing elastance, and hysteresis.......Anal acoustic reflectometry is a new technique of assessing anal sphincter function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, the opening and closing elastance, and hysteresis....

  17. Acoustic surface cavitation

    OpenAIRE

    Zijlstra, Aaldert Geert

    2011-01-01

    Merely the presence of compressible entities, known as bubbles, greatly enriches the physical phenomena encountered when introducing ultrasound in a liquid. Mediated by the response of these bubbles, the otherwise diffuse and relatively low energy density of the acoustic field can induce strong, localized liquid motion, high internal temperatures and pressures as well as secondary acoustic emissions. In turn, these effects give rise to considerable stresses exerted on nearby objects and molec...

  18. Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface.

    Science.gov (United States)

    Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A

    2014-01-01

    Metasurfaces are a family of novel wavefront-shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality to their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a design and realization of an acoustic metasurface based on tapered labyrinthine metamaterials. The demonstrated metasurface can not only steer an acoustic beam as expected from the generalized Snell's law, but also exhibits various unique properties such as conversion from propagating wave to surface mode, extraordinary beam-steering and apparent negative refraction through higher-order diffraction. Such designer acoustic metasurfaces provide a new design methodology for acoustic signal modulation devices and may be useful for applications such as acoustic imaging, beam steering, ultrasound lens design and acoustic surface wave-based applications. PMID:25418084

  19. Binary mask programmable hologram.

    Science.gov (United States)

    Tsang, P W M; Poon, T-C; Zhou, Changhe; Cheung, K W K

    2012-11-19

    We report, for the first time, the concept and generation of a novel Fresnel hologram called the digital binary mask programmable hologram (BMPH). A BMPH is comprised of a static, high resolution binary grating that is overlaid with a lower resolution binary mask. The reconstructed image of the BMPH can be programmed to approximate a target image (including both intensity and depth information) by configuring the pattern of the binary mask with a simple genetic algorithm (SGA). As the low resolution binary mask can be realized with less stringent display technology, our method enables the development of simple and economical holographic video display.

  20. Flexible programmable logic module

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Perry J. (Albuquerque, NM); Hutchinson, Robert L. (Albuquerque, NM); Pierson, Lyndon G. (Albuquerque, NM)

    2001-01-01

    The circuit module of this invention is a VME board containing a plurality of programmable logic devices (PLDs), a controlled impedance clock tree, and interconnecting buses. The PLDs are arranged to permit systolic processing of a problem by offering wide data buses and a plurality of processing nodes. The board contains a clock reference and clock distribution tree that can drive each of the PLDs with two critically timed clock references. External clock references can be used to drive additional circuit modules all operating from the same synchronous clock reference.

  1. Programmable ferroelectric tunnel memristor

    OpenAIRE

    Andy eQuindeau; Dietrich eHesse; Marin eAlexe

    2014-01-01

    We report an analogously programmable memristor based on genuine electronic resistive switching combining ferroelectric switching and electron tunneling. The tunnel current through an 8 unit cell thick epitaxial Pb(Zr[0.2]Ti[0.8])O[3] film sandwiched between La[0.7]Sr[0.3]MnO[3] and cobalt electrodes obeys the Kolmogorov-Avrami-Ishibashi model for bidimensional growth with a characteristic switching time in the order of 10^-7 seconds. The analytical description of switching kinetics allows us...

  2. Programme Biology - Health protection

    International Nuclear Information System (INIS)

    The scientific results for 1975, of the five-year Biology-Health Protection programme adopted in 1971, are presented in two volumes. In volume one, Research in Radiation Protection are developed exclusively, including the following topics: measurement and interpretation of radiation (dosimetry); transfer of radioactive nuclides in the constituents of the environment; hereditary effects of radiation; short-term effects (acute irradiation syndrome and its treatment); long-term effects and toxicology of radioactive elements. In volume, two Research on applications in Agriculture and Medicine are developed. It includes: mutagenesis; soil-plant relations; radiation analysis; food conservation; cell culture; radioentomology. Research on applications in Medicine include: Nuclear Medicine and Neutron Dosimetry

  3. CASINDO Programme Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Van der Linden, N.; Smekens, K.; Bole-Rentel, T.; Saidi, R. [Unit ECN Policy Studies, Energy research Centre of the Netherlands ECN, Petten (Netherlands); Wijnker, M. [Eindhoven University of Technology TUE, Eindhoven (Netherlands); Kamphuis, E. [ETC Netherlands, Leusden (Netherlands); Winarno, Oetomo Tri [Institute of Technology, Bandung (Indonesia); Permana, Iman [Technical Education Development Centre, Bandung (Indonesia)

    2012-06-15

    The overall objective of the CASINDO programme is to establish a self-sustaining and self-developing structure at both the national and regional level to build and strengthen human capacity to enable the provinces of North Sumatra, Yogyakarta, Central Java, West Nusa Tenggara and Papua to formulate sound policies for renewable energy and energy efficiency and to develop and implement sustainable energy projects. CASINDO stands for Capacity development and strenghtening for energy policy formulation adn implementation of sustainable energy projects in Indonesia.

  4. Accident prevention programme

    International Nuclear Information System (INIS)

    This study by the Steel Industry Safety and Health Commission was made within the context of the application by undertakings of the principles of accident and disease prevention previously adopted by the said Commission. It puts forward recommendations for the effective and gradual implementation of a programme of action on occupational health and safety in the various departments of an undertaking and in the undertaking as a whole. The methods proposed in this study are likely to be of interest to all undertakings in the metallurgical industry and other industrial sectors

  5. Progress in Programmable Logic

    Directory of Open Access Journals (Sweden)

    Jozef Cuntala

    2004-01-01

    Full Text Available Programmable logic devices (PLD are situated on important place among microelectronic components thanks to the continuing technological development of semiconductor components, due to new architectures and new approaches to digital systems design. Software design of various complicated digital systems becomes advantageous article of many firms. The Department of Electronics and Electrotechnology pays pemanent attention to mentioned components in application field. The collective of authors wants in this article point out on possibilities of design of digital system using the PLD. The paper plan contains the following basic parts: Technological aspects that influence development of configurable logic devices, Methodology od design and implementation and Flexibility of PLD interface.

  6. A programmable Fortran preprocessor

    Energy Technology Data Exchange (ETDEWEB)

    Rosing, M.

    1995-06-01

    A programmable Fortran preprocessor is described. It allows users to define compile time operations that can examine and modify the source tree before it is compiled with a traditional compiler. This intermediate step allows the definition of routines and operations that adapt to the context in which they are used. Context sensitive operations increase the flexibility of abstractions that can be built without degrading efficiency, as compared to using traditional run time based abstractions such as libraries or objects. The preprocessor is described briefly along with an example of how it is used to add CMFortran array operations to Fortran77. Other preprocessors that have been implemented are also briefly described.

  7. Acoustic vector sensor signal processing

    Institute of Scientific and Technical Information of China (English)

    SUN Guiqing; LI Qihu; ZHANG Bin

    2006-01-01

    Acoustic vector sensor simultaneously, colocately and directly measures orthogonal components of particle velocity as well as pressure at single point in acoustic field so that is possible to improve performance of traditional underwater acoustic measurement devices or detection systems and extends new ideas for solving practical underwater acoustic engineering problems. Although acoustic vector sensor history of appearing in underwater acoustic area is no long, but with huge and potential military demands, acoustic vector sensor has strong development trend in last decade, it is evolving into a one of important underwater acoustic technology. Under this background, we try to review recent progress in study on acoustic vector sensor signal processing, such as signal detection, DOA estimation, beamforming, and so on.

  8. Fast reactor programme

    International Nuclear Information System (INIS)

    This progress report summarizes the fast reactor research carried out by ECN during the period covering the year 1980. This research is mainly concerned with the cores of sodium-cooled breeders, in particular the SNR-300, and its related safety aspects. It comprises six items: A programme to determine relevant nuclear data of fission- and corrosion-products; A fuel performance programme comprising in-pile cladding failure experiments and a study of the consequences of loss-of-cooling and overpower; Basic research on fuel; Investigation of the changes in the mechanical properties of austenitic stainless steel DIN 1.4948 due to fast neutron doses, this material has been used in the manufacture of the reactor vessel and its internal components; Study of aerosols which could be formed at the time of a fast reactor accident and their progressive behaviour on leaking through cracks in the concrete containment; Studies on heat transfer in a sodium-cooled fast reactor core. As fast breeders operate at high power densities, an accurate knowledge of the heat transfer phenomena under single-phase and two-phase conditions is sought. (Auth.)

  9. PREPARATION FOR RETIREMENT PROGRAMME

    CERN Multimedia

    Human Resources Division

    2001-01-01

    27 March 2001 from 2.00 p.m. to 5.30 p.m. 28 March 2001 from 2.00 p.m. to 5.30 p.m. 29 March 2001 from 2.00 p.m. to 5.30 p.m. 30 March 2001 from 2.00 p.m. to 4.45 p.m. Auditorium (Main Building) After the success of the preparation seminars held in recent years, it has been decided that the programme should continue. The forthcoming seminar has been prepared in close collaboration with the CERN Pensioners' Association. The programme will be organised over several half-day sessions. Once again this year, a special session will be devoted to the 10th revision of the Swiss state pension scheme, the 'AVS' (Assurance-Vieillesse et Survivants), and the consequences for international civil servants. A talk will be given by Mrs Danièle Siebold, Director of the Caisse Cantonale Genevoise de Compensation, aimed mainly at those residing in or intending to move to Switzerland, or who worked in Switzerland before joining CERN. To enable Mrs Siebold to respond to your concerns as effectively as possible, please ...

  10. Accelerator programme at CAT

    International Nuclear Information System (INIS)

    The Accelerator Programme at the Centre for Advanced Technology (CAT), Indore, has very broad based concept under which all types of accelerators are to be taken up for design and fabrication. This centre will be housing a wide variety of accelerators to serve as a common facility for the universities, national laboratories in addition to laboratories under the Department of Atomic Energy. In the first phase of the programme, a series of electron accelerators are designed and fabricated. They are synchrotron radiation sources of 450 MeV (INDUS-I) and of 2 GeV (INDUS-II), microtron upto energy of 20 MeV, linear accelerator upto 20 MeV, and DC Accelerator for industrial irradiation upto 750 KeV and 20 KW. A proton accelerator of 300 MeV with 20 MeV linac injector is also designed. CAT is also developing a strong base for support technologies like ultra high vacuum, radio frequency and microwaves, DC pulsed and superconducting magnets, power supplies and controls etc. These technologies are very useful for other industrial applications also. To develop user groups to utilise INDUS-II synchrotron radiation source, a batch production of rotating Anode X-ray generators with power supplies has been initiated. So also, the sputter ion pumps, electron guns, turbo molecular pumps are brought into batch production. (author)

  11. Copernicus Earth observation programme

    Science.gov (United States)

    Žlebir, Silvo

    European Earth observation program Copernicus is an EU-wide programme that integrates satellite data, in-situ data and modeling to provide user-focused information services to support policymakers, researchers, businesses and citizens. Land monitoring service and Emergency service are fully operational already, Atmosphere monitoring service and Marine environment monitoring service are preoperational and will become fully operational in the following year, while Climate change service and Security service are in an earlier development phase. New series of a number of dedicated satellite missions will be launched in the following years, operated by the European Space Agency and EUMETSAT, starting with Sentinel 1A satellite early this year. Ground based, air-borne and sea-borne in-situ data are provided by different international networks and organizations, EU member states networks etc. European Union is devoting a particular attention to secure a sustainable long-term operational provision of the services. Copernicus is also stated as a European Union’s most important contribution to Global Earth Observation System of Systems (GEOSS). The status and the recent development of the Copernicus programme will be presented, together with its future perspective. As Copernicus services have already demonstrated their usability and effectiveness, some interesting cases of their deployment will be presented. Copernicus free and open data policy, supported by a recently adopted EU legislative act, will also be presented.

  12. Sound radiation of 3-MHz driven gas bubbles

    NARCIS (Netherlands)

    Grossmann, Siegfried; Hilgenfeldt, Sascha; Lohse, Detlef; Zomack, Michael

    1997-01-01

    The sound radiation of 3-MHz acoustically driven air bubbles in liquid is analyzed with respect to possible applications in second harmonic ultrasound diagnostics devices, which have recently come into clinical use. In the forcing pressure amplitude Pa = 1–10 atm and ambient radius R0 = 0.5–5 µm par

  13. CAMAC modular programmable function generator

    International Nuclear Information System (INIS)

    A CAMAC modular programmable function generator has been developed. The device contains a 1024 word by 12-bit memory, a 12-bit digital-to-analog converter with a 600 ns settling time, an 18-bit programmable frequency register, and two programmable trigger output registers. The trigger registers can produce programmed output logic transitions at various (binary) points in the output function curve, and are used to synchronize various other data acquisition devices with the function curve

  14. Dynamics of coupled light waves and electron-acoustic waves.

    Science.gov (United States)

    Shukla, P K; Stenflo, L; Hellberg, M

    2002-08-01

    The nonlinear interaction between coherent light waves and electron-acoustic waves in a two-electron plasma is considered. The interaction is governed by a pair of equations comprising a Schrödinger-like equation for the light wave envelope and a driven (by the light pressure) electron-acoustic wave equation. The newly derived nonlinear equations are used to study the formation and dynamics of envelope light wave solitons and light wave collapse. The implications of our investigation to space and laser-produced plasmas are pointed out.

  15. The Global Atmosphere Watch Programme: New Challenges and Opportunities

    Science.gov (United States)

    Terblanche, D. E.; Tarasova, O. A.

    2015-12-01

    The Global Atmosphere Watch Programme, one of the tree research Programmes of the World Meteorological Organization (WMO/GAW) is the only existing long-term international global programme that coordinates observations and analysis of atmospheric composition changes. The GAW Programme builds on a partnership of more than 100 countries. Within its 25 years of existence WMO/GAW has matured to the system that provides reliable long-term high quality observations in support of international policy making. WMO/GAW includes globally coordinated observational network, complemented by a comprehensive quality assurance system and capacity development. In spite of the fact that GAW has embraced the IGACO strategy (Integrated Global Atmospheric Chemistry Observations), the programme in its current form still has a strong observational bias. Future development of WMO/GAW requires the further evolution of the programme concept toward "science for services". New challenges call for the changes in the GAW station requirements and data managements, for new approaches to collaboration with the contributing networks and better involvement of the modelling community. The programme structure is evolving to streamline better to user requirements with the move from precipitation chemistry to total deposition and from near-real-time data delivery to applications (modeling) requiring such data delivery. The updated concept of GAW will include more cross-cutting applications. A new category of local station is introduced to help with the verification of some applications including those related to urban areas and the impacts of urban complexes regionally and globally. The evolution of the GAW Programme towards user driven cross-cutting applications provides a new opportunity to the National Meteorological and Hydrological Services in partnership with other science - based institutions to increase their relevance to society.

  16. The Hawaii Fruit Fly Area-Wide Pest Management Programme: Influence of a good education and partnerships in a successful programme

    International Nuclear Information System (INIS)

    Full text: Introduction: In 1999, USDA-ARS launched the 'Hawaii Fruit Fly Area-Wide Pest Management (AWPM) Program' as a 5-yr programme to suppress fruit flies below economic thresholds while reducing the use of organophosphate insecticides. The programme involved developing and integrating biologically-based pest technologies into a comprehensive management package that will be economically viable, environmentally sensitive and sustainable. Technologies included: 1) field sanitation, 2) protein bait sprays and/or traps, 3) male annihilation with male lures and attractants, and if needed, 4) augmentative parasitoid releases and 5) sterile insect releases. Many of these technologies were developed by ARS in Hawaii; however, they had never been packaged and transferred to Hawaiian farmers. Education: A critical component of successful area-wide pest management (AWPM) programmes is an organised, coordinated and comprehensive outreach educational programme. The Hawaii area-wide fruit fly pest management (HAW-FLYPM) programme's educational programme, utilised the 'logic model' approach to organise, plan, execute and evaluate farmer and community educational programmes statewide. The logic model approach was an outcome-driven rather than activity-based method that employed a linear sequence that developed relationships between programme inputs, outputs and outcomes. This model was utilised extensively to transfer sustainable, science-based technologies to suppress tephritid fruit fly pests. HAW-FLYPM's educational programme targeted growers and community door yard growers, three teaching curricula aimed at elementary through high school students, and a statewide awareness programme for the public at large. Additional key components of the HAWFLYPM education programme was the development of implementation schedules used to track programme progress, a comprehensive media matrix developed to ensure educational materials met the needs of target audience groups, and a

  17. Acoustic comfort in eating establishments

    DEFF Research Database (Denmark)

    Svensson, David; Jeong, Cheol-Ho; Brunskog, Jonas

    2014-01-01

    The subjective concept of acoustic comfort in eating establishments has been investigated in this study. The goal was to develop a predictive model for the acoustic comfort, by means of simple objective parameters, while also examining which other subjective acoustic parameters could help explain...... the feeling of acoustic comfort. Through several layers of anal ysis, acoustic comfort was found to be rather complex, and could not be explained entirely by common subjective parameters such as annoyance, intelligibility or privacy. A predictive model for the mean acoustic comfort for an eating establishment...

  18. Phononic crystals and acoustic metamaterials

    Directory of Open Access Journals (Sweden)

    Ming-Hui Lu

    2009-12-01

    Full Text Available Phononic crystals have been proposed about two decades ago and some important characteristics such as acoustic band structure and negative refraction have stimulated fundamental and practical studies in acoustic materials and devices since then. To carefully engineer a phononic crystal in an acoustic “atom” scale, acoustic metamaterials with their inherent deep subwavelength nature have triggered more exciting investigations on negative bulk modulus and/or negative mass density. Acoustic surface evanescent waves have also been recognized to play key roles to reach acoustic subwavelength imaging and enhanced transmission.

  19. Climate Ambassador Programmes in Municipalities

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Pedersen, Stine Rahbek

    2016-01-01

    Some Danish municipalities have developed ambassador programmes which generate environmental and climate change mitigation efforts in local public administrations and institutions. This chapter analyses the characteristics and experiences of four ambassador programmes now operating...... in the municipalities of Furesø, Lyngby-Taarbæk, Frederiksberg and Hvidovre. Two of the ambassador programmes presented here focus primarily on climate change mitigation initiatives, and two have a broader focus on sustainable development. Important elements for the impact of these programmes are the networking among...

  20. HKU's double professional civil engineering and law programme

    OpenAIRE

    Yeung, AT; Ng, ST; Tham, LG; Lee, PKK

    2010-01-01

    The scale and complexity of civil engineering projects are increasing exponentially. Coupled with the growing trend of globalisation, the demand for high-calibre civil engineers who are also knowledgeable in legal matters is increasing. Driven by an aspiration to prepare civil engineering graduates with a solid foundation in both civil engineering and law, The University of Hong Kong has developed the first 5-year credit-based double professional degree programme in Hong Kong, which leads to ...

  1. Programmable ferroelectric tunnel memristor

    Directory of Open Access Journals (Sweden)

    Andy eQuindeau

    2014-02-01

    Full Text Available We report an analogously programmable memristor based on genuine electronic resistive switching combining ferroelectric switching and electron tunneling. The tunnel current through an 8 unit cell thick epitaxial Pb(Zr[0.2]Ti[0.8]O[3] film sandwiched between La[0.7]Sr[0.3]MnO[3] and cobalt electrodes obeys the Kolmogorov-Avrami-Ishibashi model for bidimensional growth with a characteristic switching time in the order of 10^-7 seconds. The analytical description of switching kinetics allows us to develop a characteristic transfer function that has only one parameter viz. the characteristic switching time and fully predicts the resistive states of this type of memristor.

  2. INDUSTRIAL RISK Programme development

    International Nuclear Information System (INIS)

    INC-DTCI ICIS Rm. Valcea conducts basic and applied research among which there is the INDUSTRIAL RISK Programme that comprises studies of risk analysis and evaluation at objectives and activities in zones were risk factors are in operation, factors leading potentially to natural or technological disasters. The risk analysis and evaluation methodology proposed is a follow-up of the action plan for risk reduction in industry. The risk management refers to risk and its components assessment and identification of places where improvements are to be introduced. The risk analysis and evaluation model was developed for installations in chemical industry and are also applicable for the installations of heavy water production by H2O-H2S isotopic exchange. The risk studies supply information necessary in making decisions, aiming at preventing the operation incidence and reducing their consequences

  3. Photovoltaic programme - edition 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This publication issued by the Swiss Federal Office of Energy's Photovoltaics (PV) Programme presents an overview (in English) of activities and projects in the photovoltaics research and pilot and demonstration area in Switzerland. Progress in the area of future solar cell technologies, modules and building integration, system technologies, planning and operating aids is summarised. Also, PV for applications in developing countries, thermo-photovoltaics and international co-operation are commented on. In the area of pilot and demonstration projects, component development, PV integration in sloping roofs, on flat roofs and noise barriers as well as further PV plant are looked at. Also, measurement campaigns, studies, statistics and further PV-related topics are summarised. This volume also presents the abstracts of reports made by the project managers of 73 research and pilot and demonstration projects in these areas for 2002.

  4. Country programme review Bangladesh

    International Nuclear Information System (INIS)

    A five-expert mission was organized from 21-26 August 1993 and this document reflects the findings and recommendations of the team. Intensive contacts with heads of institutions, scientists and decision making persons in various sectors in the country were co-ordinated by the Bangladesh Atomic Energy Commission. The terms of reference of the mission were: To assess the on-going TC projects; to assist the Bangladesh nationals to finalize the formulation of the new requests for 1995-96 TC programme and to establish priority areas with regard to the introduction of national projects involving accelerated technological transfer in order to catalyze national development plans in specific areas; to examine institutional framework suitable for the introduction of these priority nuclear techniques

  5. Wavefront Modulation and Subwavelength Diffractive Acoustics with an Acoustic Metasurface

    OpenAIRE

    Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A.

    2014-01-01

    Metasurfaces are a family of novel wavefront shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality as their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a desig...

  6. ACOUSTICS IN ARCHITECTURAL DESIGN, AN ANNOTATED BIBLIOGRAPHY ON ARCHITECTURAL ACOUSTICS.

    Science.gov (United States)

    DOELLE, LESLIE L.

    THE PURPOSE OF THIS ANNOTATED BIBLIOGRAPHY ON ARCHITECTURAL ACOUSTICS WAS--(1) TO COMPILE A CLASSIFIED BIBLIOGRAPHY, INCLUDING MOST OF THOSE PUBLICATIONS ON ARCHITECTURAL ACOUSTICS, PUBLISHED IN ENGLISH, FRENCH, AND GERMAN WHICH CAN SUPPLY A USEFUL AND UP-TO-DATE SOURCE OF INFORMATION FOR THOSE ENCOUNTERING ANY ARCHITECTURAL-ACOUSTIC DESIGN…

  7. Practical acoustic emission testing

    CERN Document Server

    2016-01-01

    This book is intended for non-destructive testing (NDT) technicians who want to learn practical acoustic emission testing based on level 1 of ISO 9712 (Non-destructive testing – Qualification and certification of personnel) criteria. The essential aspects of ISO/DIS 18436-6 (Condition monitoring and diagnostics of machines – Requirements for training and certification of personnel, Part 6: Acoustic Emission) are explained, and readers can deepen their understanding with the help of practice exercises. This work presents the guiding principles of acoustic emission measurement, signal processing, algorithms for source location, measurement devices, applicability of testing methods, and measurement cases to support not only researchers in this field but also and especially NDT technicians.

  8. Passive broadband acoustic thermometry

    Science.gov (United States)

    Anosov, A. A.; Belyaev, R. V.; Klin'shov, V. V.; Mansfel'd, A. D.; Subochev, P. V.

    2016-04-01

    The 1D internal (core) temperature profiles for the model object (plasticine) and the human hand are reconstructed using the passive acoustothermometric broadband probing data. Thermal acoustic radiation is detected by a broadband (0.8-3.5 MHz) acoustic radiometer. The temperature distribution is reconstructed using a priori information corresponding to the experimental conditions. The temperature distribution for the heated model object is assumed to be monotonic. For the hand, we assume that the temperature distribution satisfies the heat-conduction equation taking into account the blood flow. The average error of reconstruction determined for plasticine from the results of independent temperature measurements is 0.6 K for a measuring time of 25 s. The reconstructed value of the core temperature of the hand (36°C) generally corresponds to physiological data. The obtained results make it possible to use passive broadband acoustic probing for measuring the core temperatures in medical procedures associated with heating of human organism tissues.

  9. Acoustics waves and oscillations

    CERN Document Server

    Sen, S.N.

    2013-01-01

    Parameters of acoustics presented in a logical and lucid style Physical principles discussed with mathematical formulations Importance of ultrasonic waves highlighted Dispersion of ultrasonic waves in viscous liquids explained This book presents the theory of waves and oscillations and various applications of acoustics in a logical and simple form. The physical principles have been explained with necessary mathematical formulation and supported by experimental layout wherever possible. Incorporating the classical view point all aspects of acoustic waves and oscillations have been discussed together with detailed elaboration of modern technological applications of sound. A separate chapter on ultrasonics emphasizes the importance of this branch of science in fundamental and applied research. In this edition a new chapter ''Hypersonic Velocity in Viscous Liquids as revealed from Brillouin Spectra'' has been added. The book is expected to present to its readers a comprehensive presentation of the subject matter...

  10. Acoustic detection of pneumothorax

    Science.gov (United States)

    Mansy, Hansen A.; Royston, Thomas J.; Balk, Robert A.; Sandler, Richard H.

    2003-04-01

    This study aims at investigating the feasibility of using low-frequency (pneumothorax detection were tested in dogs. In the first approach, broadband acoustic signals were introduced into the trachea during end-expiration and transmitted waves were measured at the chest surface. Pneumothorax was found to consistently decrease pulmonary acoustic transmission in the 200-1200-Hz frequency band, while less change was observed at lower frequencies (ppneumothorax states (pPneumothorax was found to be associated with a preferential reduction of sound amplitude in the 200- to 700-Hz range, and a decrease of sound amplitude variation (in the 300 to 600-Hz band) during the respiration cycle (pPneumothorax changed the frequency and decay rate of percussive sounds. These results imply that certain medical conditions may be reliably detected using appropriate acoustic measurements and analysis. [Work supported by NIH/NHLBI #R44HL61108.

  11. A Century of Acoustic Metrology

    DEFF Research Database (Denmark)

    Rasmussen, Knud

    1998-01-01

    The development in acoustic measurement technique over the last century is reviewed with special emphasis on the metrological aspect.......The development in acoustic measurement technique over the last century is reviewed with special emphasis on the metrological aspect....

  12. Advanced Active Acoustics Lab (AAAL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Active Acoustics Lab (AAAL) is a state-of-the-art Undersea Warfare (USW) acoustic data analysis facility capable of both active and passive underwater...

  13. Programmable architecture for quantum computing

    NARCIS (Netherlands)

    Chen, J.; Wang, L.; Charbon, E.; Wang, B.

    2013-01-01

    A programmable architecture called “quantum FPGA (field-programmable gate array)” (QFPGA) is presented for quantum computing, which is a hybrid model combining the advantages of the qubus system and the measurement-based quantum computation. There are two kinds of buses in QFPGA, the local bus and t

  14. An automatic bibliography indexing programme

    Directory of Open Access Journals (Sweden)

    J. W. Morris

    1974-12-01

    Full Text Available A relatively simple FORTRAN IV programme, designed for a small computer, for author and key-word indexes to bibliographic records is described, and examples of output are given. It is com­pared with some other systems. Suggested improvements to the programme are given.

  15. Japan's Eco-School Programme

    Science.gov (United States)

    Mori, Masayuki

    2007-01-01

    Since 1997, several ministries in Japan have collaborated on an eco-school programme, which applies to both newly constructed and renovated school buildings, in an effort to make its schools more environmentally friendly. The programme equips school buildings with ecological features such as photovoltaic cells, solar thermal collectors, other new…

  16. Densitometry By Acoustic Levitation

    Science.gov (United States)

    Trinh, Eugene H.

    1989-01-01

    "Static" and "dynamic" methods developed for measuring mass density of acoustically levitated solid particle or liquid drop. "Static" method, unknown density of sample found by comparison with another sample of known density. "Dynamic" method practiced with or without gravitational field. Advantages over conventional density-measuring techniques: sample does not have to make contact with container or other solid surface, size and shape of samples do not affect measurement significantly, sound field does not have to be know in detail, and sample can be smaller than microliter. Detailed knowledge of acoustic field not necessary.

  17. Acoustic classification of dwellings

    DEFF Research Database (Denmark)

    Berardi, Umberto; Rasmussen, Birgit

    2014-01-01

    insulation performance, national schemes for sound classification of dwellings have been developed in several European countries. These schemes define acoustic classes according to different levels of sound insulation. Due to the lack of coordination among countries, a significant diversity in terms...... of descriptors, number of classes, and class intervals occurred between national schemes. However, a proposal “acoustic classification scheme for dwellings” has been developed recently in the European COST Action TU0901 with 32 member countries. This proposal has been accepted as an ISO work item. This paper...

  18. Strong acoustic wave action

    Science.gov (United States)

    Gokhberg, M. B.

    1983-07-01

    Experiments devoted to acoustic action on the atmosphere-magnetosphere-ionosphere system using ground based strong explosions are reviewed. The propagation of acoustic waves was observed by ground observations over 2000 km in horizontal direction and to an altitude of 200 km. Magnetic variations up to 100 nT were detected by ARIEL-3 satellite near the epicenter of the explosion connected with the formation of strong field aligned currents in the magnetosphere. The enhancement of VLF emission at 800 km altitude is observed.

  19. Structural Acoustics and Vibrations

    Science.gov (United States)

    Chaigne, Antoine

    This structural chapter is devoted to vibrations of structures and to their coupling with the acoustic field. Depending on the context, the radiated sound can be judged as desirable, as is mostly the case for musical instruments, or undesirable, like noise generated by machinery. In architectural acoustics, one main goal is to limit the transmission of sound through walls. In the automobile industry, the engineers have to control the noise generated inside and outside the passenger compartment. This can be achieved by means of passive or active damping. In general, there is a strong need for quieter products and better sound quality generated by the structures in our daily environment.

  20. A theory-driven evaluation of a wellness initiative

    Directory of Open Access Journals (Sweden)

    Carren Field

    2012-07-01

    Full Text Available Orientation: By reporting on an evaluation of a wellness initiative, this article brings together an element of organisational development (employee wellness with an approach to programme evaluation (programme theory-driven evaluation. Research purpose: Two questions were addressed: ‘What is the causal logic of the wellness initiative?’ and ‘Is this a plausible programme theory according to social science research and literature?’Motivation for the study: A study that could demonstrate the usefulness of the theory-driven evaluation approach, especially in the local human resource (HR domain, was considered to be valuable. In addition, this evaluation provided a careful consideration of how plausible it is for such interventions to achieve what they set out to do.Research design, approach and method: The evaluation relied mainly on qualitative methods (the examination of secondary data and interviewing to extract programme theory, and on literature to assess plausibility.Main findings: The study had two main outcomes: the finalisation of a model of how the programme is supposed to work according to programme staff, and the conclusion that the model is plausible, provided it is implemented at full strength.Practical/managerial implications: Programme staff are advised to pay particular attention to implementation fidelity, especially to employee participation and involvement in the programme’s activities. A number of strategies are recommended to strengthen the effect of the model.Contribution/value-add: This evaluation showed the importance of conducting a theory- driven evaluation, not only in order to understand the programme and its context, but also to provide a basis for an implementation and outcome evaluation.

  1. International Programmes on ADS: European Commission

    International Nuclear Information System (INIS)

    Euratom research projects related to the design and the use of ADS facilities started in the 4th Framework Programme (FP4) (1996–2001) with the project ‘Impact of Accelerator Based Technologies on Nuclear Fission Safety—IABAT’. The overall objective of the IABAT project was a preliminary assessment of the potential of Accelerator Driven Systems for transmutation of radioactive waste and, additionally, for nuclear energy production with minimum waste generation. This first project was followed by a much larger ADS oriented programmes in the FP5 (2002–2005), FP6 (2005–2010) and FP7 (2008–2013). In the frame of the FP6, special attention was devoted to the EUROTRANS integrated Project (2005–2010), dedicated to study the transmutation of high level radioactive waste in an ADS. Based on the three FP5 Clusters FUETRA, BASTRA and TESTRA together with the PDS-XADS Project, the EUROTRANS Project was aimed to carry out a first advanced design of an approximately 50 to 100 MWth eXperimental facility (realization in a short term, say about 10 years) demonstrating the technical feasibility of Transmutation in an ADS (XT ADS), as well as to accomplish a generic conceptual design (several 100 MWth) of a modular European Facility for Industrial Transmutation (EFIT) (realisation in the long term)

  2. Variable-Position Acoustic Levitation

    Science.gov (United States)

    Barmatz, M. B.; Stoneburner, J. D.; Jacobi, N.; Wang, T. G.

    1983-01-01

    Method of acoustic levitation supports objects at positions other than acoustic nodes. Acoustic force is varied so it balances gravitational (or other) force, thereby maintaining object at any position within equilibrium range. Levitation method applicable to containerless processing. Such objects as table-tennis balls, hollow plastic spheres, and balsa-wood spheres levitated in laboratory by new method.

  3. How can acoustic resonance reduce the average velocity in a falling body?

    OpenAIRE

    V. Torres-Zúñiga

    2011-01-01

    In this article, a simple experiment is described to overcome the misconception that acoustic pressure and levitation effects are difficult to observe in school laboratories. Analysis of the free fall velocity of a toy parachute inside a vertical tube, driven by sound in a range of frequencies around the resonant condition, exhibits the resonance frequency, the node pressure zones, and the optimal conditions to obtain acoustical levitation of a light body.

  4. Underwater Acoustic Networking Techniques

    CERN Document Server

    Otnes, Roald; Casari, Paolo; Goetz, Michael; Husøy, Thor; Nissen, Ivor; Rimstad, Knut; van Walree, Paul; Zorzi, Michele

    2012-01-01

    This literature study presents an overview of underwater acoustic networking. It provides a background and describes the state of the art of all networking facets that are relevant for underwater applications. This report serves both as an introduction to the subject and as a summary of existing protocols, providing support and inspiration for the development of network architectures.

  5. Evoked acoustic emission

    DEFF Research Database (Denmark)

    Elberling, C; Parbo, J; Johnsen, N J;

    1985-01-01

    Stimulated acoustic emissions were recorded in response to tonal stimuli at 60 dB p.e. SPL in a small group of normal-hearing adults. Power spectral analysis reveals that the evoked activity from each ear contains energy in preferential frequency bands and the change of stimulus frequency has only...

  6. Surface Acoustic Wave Devices

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard

    The work of this project is concerned with the simulation of surface acoustic waves (SAW) and topology optimization of SAW devices. SAWs are elastic vibrations that propagate along a material surface and are extensively used in electromechanical filters and resonators in telecommunication. A new...

  7. Portable acoustic myography

    DEFF Research Database (Denmark)

    Harrison, Adrian Paul; Danneskiold-Samsøe, Bente; Bartels, Else Marie

    2013-01-01

    Muscle sound gives a local picture of muscles involved in a particular movement and is independent of electrical signals between nerve and muscle. Sound recording (acoustic myography) is a well-known noninvasive technique that has suffered from not being easily applicable, as well as not being ab...

  8. Good on paper: the gap between programme theory and real-world context in Pakistan's Community Midwife programme

    Science.gov (United States)

    Mumtaz, Z; Levay, A; Bhatti, A; Salway, S

    2015-01-01

    Objective To understand why skilled birth attendance—an acknowledged strategy for reducing maternal deaths—has been effective in some settings but is failing in Pakistan and to demonstrate the value of a theory-driven approach to evaluating implementation of maternal healthcare interventions. Design Implementation research was conducted using an institutional ethnographic approach. Setting and population National programme and local community levels in Pakistan. Methods Observations, focus group discussions, and in-depth interviews were conducted with 38 Community Midwives (CMWs), 20 policymakers, 45 healthcare providers and 136 community members. A critical policy document review was conducted. National and local level data were brought together. Main outcomes Alignment of programme theory with real-world practice. Results Data revealed gaps between programme theory, assumptions and reality on the ground. The design of the programme failed to take into account: (1) the incongruity between the role of a midwife and dominant class and gendered norms that devalue such a role; (2) market and consumer behaviour that prevented CMWs from establishing private practices; (3) the complexity of public–private sector cooperation. Uniform deployment policies failed to consider existing provider density and geography. Conclusions Greater attention to programme theory and the ‘real-world’ setting during design of maternal health strategies is needed to achieve consistent results in different contexts. PMID:25315837

  9. The BGAN extension programme

    Science.gov (United States)

    Rivera, Juan J.; Trachtman, Eyal; Richharia, Madhavendra

    2005-11-01

    Mobile satellite telecommunications systems have undergone an enormous evolution in the last decades, with the interest in having advanced telecommunications services available on demand, anywhere and at any time, leading to incredible advances. The demand for braodband data is therefore rapidly gathering pace, but current solutions are finding it increasingly difficult to combine large bandwidth with ubiquitous coverage, reliability and portability. The BGAN (Broadband Global Area Network) system, designed to operate with the Inmarsat-4 satellites, provides breakthrough services that meet all of these requirements. It will enable broadband connection on the move, delivering all the key tools of the modern office. Recognising the great impact that Inmarsat's BGAN system will have on the European satellite communications industry, and the benefits that it will bring to a wide range of European industries, in 2003 ESA initiated the "BGAN Extension" project. Its primary goals are to provide the full range of BGAN services to truly mobile platforms, operating in aeronautical, vehicular and maritime environments, and to introduce a multicast service capability. The project is supported by the ARTES Programme which establishes a collaboration agreement between ESA, Inmarsat and a group of key industrial and academic institutions which includes EMS, Logica, Nera and the University of Surrey (UK).

  10. Fusion technology programme

    International Nuclear Information System (INIS)

    In 1982, KfK joined the fusion programme of EURATOM as a further association introducing its experience in nuclear technology. KfK closely cooperates with IPP Garching, the two institutions forming a research unit aiming at planning and realization of future development steps of fusion. KfK has combined its forces in the Nuclear Fusion Project (PKF) with participation of several KfK departments to the project tasks. Previous work of KfK in magnetic fusion has addressed mainly superconducting magnets, plasma heating by cluster ions and studies on structural materials. At present, emphasis of our work has concentrated increasingly on the nuclear part, i.e. the first wall and blanket structures and the elements of the tritium extraction and purification system. Associated to this component development are studies of remote maintenance and safety. Most of the actual work addresses NET, the next step to a demonstration of fusion feasibility. NET is supposed to follow JET, the operating plasma physics experiment of Euratom, on the 1990's. Detailed progress of the work in the past half year is described in this report. (orig./GG)

  11. ALICE pp physics programme

    CERN Document Server

    Kraus, Ingrid

    2009-01-01

    The physics programme of the ALICE experiment at CERN-LHC comprises besides studies of high-energy heavy-ion collisions measurements of proton-proton interactions at unprecedented energies, too. This paper focuses on the global event characterisation in terms of the multiplicity distribution of charged hadrons and mean transverse momentum. These bulk observables become accessible because the detector features excellent track reconstruction, especially at low transverse momenta. The measurement of strange hadrons is of particular interest since the strange-particle phase-space was found to be suppressed beyond canonical reduction at lower center-of-mass energies and the production mechanism of soft particles is not yet fully understood. Here we benefit in particular from particle identification down to very low transverse momentum, i.e. 100 - 300 MeV/c, giving access to spectra and integrated yields of identified hadrons. Equipped with these features, ALICE will play a complementary role w.r.t. other LHC exper...

  12. SUMMER STUDENT LECTURE PROGRAMME

    CERN Multimedia

    Françoise Benz

    2002-01-01

    SUMMER STUDENT LECTURE PROGRAMME Main Auditorium, bldg. 500   DATE TIME LECTURER TITLE Monday 29 July 09:15 - 10:00 R. RATTAZZI Beyond the Standard Model (3/3) 10:15 - 11:00 P. WELLS Experimental test of the SM - LEP (3/3) 11:15 - 12:00 P. WELLS Discussion Session 14:00 - 16:00 R. ASSMANN The CLIC Concept for a Future Particle Collider at the Energy Frontier Tuesday 30 July 09:15 - 10:00 F. ANTINORI Heavy Ions (1/2) 10:15 - 12:00 F. DYDAK Neutrino Physics (1&2/4) Wednesday 31 July  09:15 - 10:00 F. ANTINORI Heavy Ions (2/2) 10:15 - 11:00 F. DYDAK Neutrino Physics (3/4) 11:15 - 12:00 F. DYDAK / F. ANTINORI Discussion Session Thursday 1 August 09:15 - 10:00 T. NAKADA CP Violation (1/4) 10:15 - 11:00 F. DYDAK Neutrino Physics (4/4) 11:15 - 12:00 F. BEDESCHI Experimental test of the SM Tevatron (1/2) Friday 2 August 09:15 - 10:00 T. NAKADA CP Violation (2/4) 10:15 ? 11:00 F. BEDESCHI Experimental test of the SM Tevatron (2/2) 11:15 ? 12:00 F. BEDESCHI / T. NAKADA Di...

  13. SUMMER STUDENT LECTURE PROGRAMME

    CERN Multimedia

    Françoise Benz

    2002-01-01

    Main Auditorium, bldg. 500   DATE TIME LECTURER TITLE Wednesday 3 July 09:15 - 10:00 L. FAYARD, O. ULLALAND Presentation of the Summer Student Programm 10:15 - 12:00 L. MAIANI Introduction to CERN (1&2/2) 14:00 - 15:00 G. Stevenson Radiation Protection (Council Chamber, bldg.503) Thursday 4 July 09:15 - 11:00 F. CLOSE Introduction to Particle Physics for non Physics Students (1&2/4) 11:15 - 12:00 C. JORAM Particle Detectors (1/5) Friday 5 July 09:15 - 11:00 F. CLOSE Introduction to Particle Physics for non Physics Students (3&4/4) 11:15 - 12:00 Discussion Session Monday 8 July 09:15 - 10:00 R. KLEISS Fundamental Concepts of Particle Physics (1/6) 10:15 - 11:00 C. JORAM Particle Detectors (2/5) 11:15 - 12:00 M. FRANKLIN Classic Experiments (1/3) 14:00 - 15:00 M. LINDROOS Isolde 15:30 - 16:30 M. LINDROOS Visit of the Experiment Tuesday 9 july 09:15 - 10:00 R. KLEISS Fundamental Concepts of Particle Physics (2/6) 10:15 - 11:00 C. JORAM Part...

  14. Photovoltaic programme, edition 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This comprehensive publication issued by the Swiss Federal Office of Energy's Photovoltaics (PV) Programme presents an overview (in English) of activities and projects in the photovoltaics research and pilot and demonstration areas in Switzerland for the year 2003. Progress in future solar cell technologies as well as in the area of modules, building integration and system technologies is summarised. Also, national and international co-operation and multi-national pilot and demonstration projects are commented on. Associated projects such as eco-balances for PV systems, forecasting and modelling tools as well as system monitoring tools are discussed. In the area of pilot and demonstration projects, component development, PV integration in sloping roofs, on flat roofs and on facades as well as further PV plant are looked at. Also, measurement campaigns, studies, statistics and other PV-related topics are summarised. This volume presents a list of 92 projects in the PV area including the appropriate Internet links and is completed with a collection of project abstracts.

  15. Programmable electronic synthesized capacitance

    Science.gov (United States)

    Kleinberg, Leonard L. (Inventor)

    1987-01-01

    A predetermined and variable synthesized capacitance which may be incorporated into the resonant portion of an electronic oscillator for the purpose of tuning the oscillator comprises a programmable operational amplifier circuit. The operational amplifier circuit has its output connected to its inverting input, in a follower configuration, by a network which is low impedance at the operational frequency of the circuit. The output of the operational amplifier is also connected to the noninverting input by a capacitor. The noninverting input appears as a synthesized capacitance which may be varied with a variation in gain-bandwidth product of the operational amplifier circuit. The gain-bandwidth product may, in turn, be varied with a variation in input set current with a digital to analog converter whose output is varied with a command word. The output impedance of the circuit may also be varied by the output set current. This circuit may provide very small ranges in oscillator frequency with relatively large control voltages unaffected by noise.

  16. FPGAs for software programmers

    CERN Document Server

    Hannig, Frank; Ziener, Daniel

    2016-01-01

    This book makes powerful Field Programmable Gate Array (FPGA) and reconfigurable technology accessible to software engineers by covering different state-of-the-art high-level synthesis approaches (e.g., OpenCL and several C-to-gates compilers). It introduces FPGA technology, its programming model, and how various applications can be implemented on FPGAs without going through low-level hardware design phases. Readers will get a realistic sense for problems that are suited for FPGAs and how to implement them from a software designer’s point of view. The authors demonstrate that FPGAs and their programming model reflect the needs of stream processing problems much better than traditional CPU or GPU architectures, making them well-suited for a wide variety of systems, from embedded systems performing sensor processing to large setups for Big Data number crunching. This book serves as an invaluable tool for software designers and FPGA design engineers who are interested in high design productivity through behavi...

  17. Summer Student Programme

    CERN Multimedia

    2006-01-01

    Date Time Title Speaker 05/07/2006 09:15 - 10:00 Presentation of the Summer Student Programme F. CERUTTI Information on Computing Rules D. HEAGERTY Workshops presentation O. ULLALAND 10:15 - 11:00 Introduction to CERN J. ENGELEN 11:15 Film on CERN 11:00 Introduction to Particle Physics F. CLOSE 11:15 - 12:00 Accelerators (1/5) S. GILARDONI / E. METRAL 12:00 Discussion Session 7/07/2006 09:15 - 11:00 Introduction to Particle Physics F. CLOSE 11:15 - 12:00 Accelerators (2/5) S. GILARDONI / E. METRAL 12:00 Discussion Session 09:15 - 10:00 Accelerators (3/5) S. GILARDONI / E. METRAL 10:15 - 12:00 Detectors (1-2/5) O. ULLALAND 12:00 Discussion Session 11/07/2006 09:15 - 10:00 Accelerators (4/5) S. GILARDONI / E. METRAL 10:15 - 11:00 Detectors (3/5) O. ULLALAND 11:15 - 12:00 Introduction to Nuclear Physics (1/4) P. CHOMAZ P. CHOMAZ 10:15 - 11:00 Accelerators (5/5) S. GILARDONI / E. METRAL 11:15 - 12:00 Detectors (4/5) O. ULLALAND 12:00 Discus...

  18. Summer Student Lecture Programme

    CERN Multimedia

    2004-01-01

    Main Auditorium, bldg. 500 More Information DATE TIME LECTURER TITLE Wednesday 7 July 09:15 - 10:00 L. Fayard, O. Ullaland, D. Heagerty (CERN) Programme Presentation Workshops presentation Information on Computing Rules 10:15 - 11:00 R. Aymar (CERN) Introduction to CERN (1/2) 11:15 - 12:00 J. Engelen (CERN) Introduction to CERN (2/2) 15:00 - 16:30 H. Menzel (CERN) An Introduction to Radiation Protection DATE TIME LECTURER TITLE Thursday 8 july 09:15 - 10:00 L. Di Lella (CERN) Introduction to Particle Physics (1/4) 10:15 - 11:00 L. Di Lella (CERN) Introduction to Particle Physics (2/4) 11:15 - 12:00 P. Chomaz (GANIL / CERN) Fundamental questions in modern nuclear physics: The challenge of exotic nuclei (1/2) DATE TIME LECTURER TITLE Friday 9 July 09:15 - 10:00 L. Di Lella (CERN) Introduction to Particle Physics (3/4) 10:15 - 11:00 P. Chomaz (GANIL / CERN) Fundamental questions in modern nuclear physics: The challenge of exotic nuclei (2/2) 11:15 - 12:00 P....

  19. Management and Communication programme

    CERN Multimedia

    Nathalie Dumeaux

    2005-01-01

    We are pleased to announce the launch of three new courses in the Management and Communication programme: 1.     Managing Time (Open to all Staff Members) The objectives are: To enhance your personal effectiveness through better organisation skills To acquire ways of making the most of your time through improved work habits To reduce stress For the description of this course, please see:  http://humanresources.web.cern.ch/humanresources/external/training/MANCO/P9798/S8E_e.asp 2.     Service Orientation (Open to all Staff Members working in a service-related function) The objectives are: To understand the key elements in an effective client/service provider relationship To develop a client focused approach to providing services For the description of this course, please see:  http://humanresources.web.cern.ch/humanresources/external/training/MANCO/P9798/serv_e.asp 3.   Introduction to Leadership (Open to Staff in Career Paths E & above, including newly appointed supervisors and Sect...

  20. Management and Communication programme

    CERN Multimedia

    Nathalie Dumeaux

    2005-01-01

    We are pleased to announce the launch of three new courses in the Management and Communication programme: 1.     Managing Time (Open to all Staff Members) The objectives are: To enhance your personal effectiveness through better organisation skills To acquire ways of making the most of your time through improved work habits To reduce stress For the description of this course, please see:  http://humanresources.web.cern.ch/humanresources/external/training/MANCO/P9798/S8E_e.asp 2.     Service Orientation (Open to all Staff Members working in a service-related function) The objectives are: To understand the key elements in an effective client/service provider relationship To develop a client focused approach to providing services For the description of this course, please see:  http://humanresources.web.cern.ch/humanresources/external/training/MANCO/P9798/serv_e.asp 3.   Introduction to Leadership (Open to Staff in Career Paths E & above, including newly appointed supervisors and Secti...

  1. Scientific Programme Committee

    Science.gov (United States)

    2013-02-01

    Scientific Programme Committee A. Blondel, University of Geneva A. Cervera, IFIC M. Dracos, IN2P3 I. Efhymiopoulos, CERN J. Ellis, CERN S. Geer, FNAL R. Garoby, CERN M. Goodman, ANL D. Harris, FNAL T. Hasegawa, KEK P. Huber, Virginia Tech. D. Kaplan, IIT Y.D. Kim, Sejong University H. Kirk, BNL Y. Kuno, Osaka University K. Long, Imperial College N.K. Mondal, TIFR J. Morfin, FNAL Y. Mori, Kyoto University K. Nishikawa, KEK V. Palladino, University of Napoli C. Prior, RAL F.J.P. Soler, University of Glasgow J. Strait, FNAL R. Svoboda, University of California Davis F. Terranova, LN Frascati M. Zisman, LBNL Local Organizing Committee E. Benedetto, CERN/NTUA C. Blanchard, University of Geneva A. Blondel, University of Geneva (co-chair) I. Efthymiopoulos, CERN (co-chair) F. Dufour, University of Geneva F. Girard-Madoux, CERN E. Gschwendtner, CERN A. Korzenev, University of Geneva M. Morer-Olafsen, CERN S. Murphy, University of Geneva G. Prior, CERN G. Wikström, University of Geneva E. Wildner, CERN Sponsors EuCARD European Organization for Nuclear Research (CERN) Swiss Institute for Particle Physics (CHIPP) University of Geneva

  2. Community-based preparedness programmes and the 2009 Australian bushfires: policy implications derived from applying theory.

    Science.gov (United States)

    MacDougall, Colin; Gibbs, Lisa; Clark, Rachel

    2014-04-01

    The Victorian Country Fire Authority in Australia runs the Community Fireguard (CFG) programme to assist individuals and communities in preparing for fire. The objective of this qualitative research was to understand the impact of CFG groups on their members' fire preparedness and response during the 2009 Australian bushfires. Social connectedness emerged as a strong theme, leading to an analysis of data using social capital theory. The main strength of the CFG programme was that it was driven by innovative community members; however, concerns arose regarding the extent to which the programme covered all vulnerable areas, which led the research team to explore the theory of diffusion of innovation. The article concludes by stepping back from the evaluation and using both applied theories to reflect on broad options for community fire preparedness programmes in general. The exercise produced two contrasting options for principles underlying community fire preparedness programmes. PMID:24601916

  3. Controlling sound with acoustic metamaterials

    DEFF Research Database (Denmark)

    Cummer, Steven A. ; Christensen, Johan; Alù, Andrea

    2016-01-01

    Acoustic metamaterials can manipulate and control sound waves in ways that are not possible in conventional materials. Metamaterials with zero, or even negative, refractive index for sound offer new possibilities for acoustic imaging and for the control of sound at subwavelength scales....... The combination of transformation acoustics theory and highly anisotropic acoustic metamaterials enables precise control over the deformation of sound fields, which can be used, for example, to hide or cloak objects from incident acoustic energy. Active acoustic metamaterials use external control to create......-scale metamaterial structures and converting laboratory experiments into useful devices. In this Review, we outline the designs and properties of materials with unusual acoustic parameters (for example, negative refractive index), discuss examples of extreme manipulation of sound and, finally, provide an overview...

  4. A Statistical Programme Assignment Model

    DEFF Research Database (Denmark)

    Rosholm, Michael; Staghøj, Jonas; Svarer, Michael

    When treatment effects of active labour market programmes are heterogeneous in an observable way  across the population, the allocation of the unemployed into different programmes becomes a particularly  important issue. In this paper, we present a statistical model designed to improve the present...... duration of unemployment spells may result if a statistical programme assignment model is introduced. We discuss several issues regarding the  plementation of such a system, especially the interplay between the statistical model and  case workers....

  5. Automatic TLI recognition system, programmer`s guide

    Energy Technology Data Exchange (ETDEWEB)

    Lassahn, G.D.

    1997-02-01

    This report describes the software of an automatic target recognition system (version 14), from a programmer`s point of view. The intent is to provide information that will help people who wish to modify the software. In separate volumes are a general description of the ATR system, Automatic TLI Recognition System, General Description, and a user`s manual, Automatic TLI Recognition System, User`s Guide. 2 refs.

  6. An acoustic energy framework for predicting combustion-driven acoustic instabilities in premixed gas-turbines

    Science.gov (United States)

    Ibrahim, Zuhair M. A.

    The purpose of this study was to discover and assess student financial services delivered to students enrolled at East Tennessee State University. The research was undertaken for institutional self-improvement. The research explored changes that have occurred in student financial services in the dynamic higher education market. The research revealed universities pursued best practices for the delivery of student financial services through expanded employee knowledge, restructured organizations, and integrated information technologies. The research was conducted during October and November, 2006. The data were gathered from an online student survey of student financial services. The areas researched included: the Bursar office, the Financial Aid office, and online services. The results of the data analysis revealed problems with the students' perceived quality of existing financial services and the additional services students desire. The research focused on student perceptions of the quality of financial services by age and gender classifications and response categories. Although no statistically significant difference was found between the age-gender classifications on the perception of the quality of the financial services studied, the research adds to our understanding of student financial services at East Tennessee State University. Recommendation for continued research included annual surveys of segmented student populations that include ethnicity, age, gender, and educational level. The research would be used for continuous improvement efforts and student relationship management. Also additional research was recommended for employee learning in relation to the institution's mission, goals, and values.

  7. Acoustic transmission in SGUs: Plant and laboratory measurements

    International Nuclear Information System (INIS)

    As part of the UK development work an experimental programme is in progress to measure the acoustic transmission through an actual reactor SGU and also through a model tube bundle in the laboratory. This paper gives an outline of the experimental arrangements and examples of the preliminary results. The data from the laboratory measurements in particular is being used for comparison with theoretical studies carried out at the University of Keele which are reported in a separate paper to this Specialist's Meeting. The plant measurements are being carried out on a Superheater unit of the Prototype Fast Reactor (PFR) at Dounreay. These measurements are primarily aimed at providing information for a loose parts condition monitoring system which is operated on the PFR SGU, but results obtained will make a significant contribution to the acoustic leak detection programme. The Superheater used for the experiment has six blank steam tubes for experimental purposes. An impacting device has been inserted into one of the blank tubes and acoustic signals recorded on waveguides which are attached to the SGU shell. Recordings were made during a reactor shutdown with static sodium in the superheater and with the impacting device at five axial positions in both the inner and outer legs of the 'U' tube. Results are given for signal attenuation and location of the acoustic noise source. The laboratory measurements are being made using a 721-tube model tube bundle in a water tank. The tube bundle which is approximately 0.75m diameter x 3 metres long is not modelled to a specific design but is of realistic size and construction. A piezo-electric acoustic source is mounted centrally in the tube bundle and the transmitted signal is received by underwater microphones on the periphery of the bundle. Results from the first experiments with water filled tubes are given covering a frequency range of 6KHz to 80KHz. The preliminary results of the experimental programme are encouraging and

  8. CERN openlab Summer Student Programme

    CERN Multimedia

    2012-01-01

    CERN openlab is currently taking applications for its summer student programme. The closing date for applications is 30 March 2012.   The openlab Summer Student Programme is open for applications from bachelor, master and PhD students in computer science and physics. Successful applicants will spend 8 weeks at CERN, during the period June to September 2012, to work with some of the latest hardware and software technologies. The programme is more than just a summer at CERN: it can lead to follow-on projects at the home institute and may even inspire the students to become entrepreneurs in cutting-edge computing technologies. A series of lectures will be given by experts in various domains of CERN related high-throughput computing. Study tours to external companies and universities as well as to CERN facilities are also part of the programme. Please visit www.cern.ch/openlab-students for more information.

  9. CERN openlab summer student programme

    CERN Multimedia

    2013-01-01

    CERN openlab is currently taking applications for its summer student programme. The closing date for applications is 31 March 2013.   The openlab summer student programme is open for applications from bachelor, master and PhD students in computer science and physics. Successful applicants will spend 9 weeks at CERN, during the period from June to September 2013, working with some of the latest hardware and software technologies. The programme is more than just a summer at CERN: it can lead to follow-on projects at the home institute and may even inspire students to become entrepreneurs in cutting-edge computing technologies. A series of lectures will be given by experts in various domains of CERN-related high-throughput computing. Study tours of external companies and universities as well as of CERN facilities are also part of the programme. Please visit the CERN openlab website for more information.

  10. The internationalisation of postgraduate programmes

    DEFF Research Database (Denmark)

    Fink, Flemming Kobberøe; Andersen, Ole K.; Bak, Thomas;

    2002-01-01

    for the international students are presented and discussed in terms of e.g. the teamwork situation, professional and cultural differences. A student enrolment programme, implemented through the provision of scholarships, jointly paid by government and industry funds is presented...

  11. Field Evaluation of Programmable Thermostats

    Energy Technology Data Exchange (ETDEWEB)

    Sachs, O. [Fraunhofer Center for Sustainable Energy Systems (CSE), Cambridge, MA (United States); Tiefenbeck, V. [Fraunhofer Center for Sustainable Energy Systems (CSE), Cambridge, MA (United States); Duvier, C. [Fraunhofer Center for Sustainable Energy Systems (CSE), Cambridge, MA (United States); Qin, A. [Fraunhofer Center for Sustainable Energy Systems (CSE), Cambridge, MA (United States); Cheney, K. [Fraunhofer Center for Sustainable Energy Systems (CSE), Cambridge, MA (United States); Akers, C. [Fraunhofer Center for Sustainable Energy Systems (CSE), Cambridge, MA (United States); Roth, K. [Fraunhofer Center for Sustainable Energy Systems (CSE), Cambridge, MA (United States)

    2012-12-01

    Prior research suggests that poor programmable thermostats usability may prevent their effective use to save energy. The Fraunhofer team hypothesized that home occupants with high-usability thermostats would be more likely to use them to save energy than people with a basic thermostats. In this report, the team discusses results of a project in which the team monitored and compared programmable thermostats with basic thermostats in an affordable housing apartment complex.

  12. The MERLIN programme: Pt. 1

    International Nuclear Information System (INIS)

    The MERLIN rig at the Northern Research Laboratories, Springfields, was intended to investigate the deformation behaviour of Zircaloy fuel rod cladding under conditions approximating those of a large break Loss of Coolant Accident (LOCA). In this rig, an assembly of electrically heated fuel rod simulators (6x6 cluster) was subjected to a temperature transient simulating that predicted to occur in a LOCA, including the initiation of bottom reflooding at a suitable stage. The main aim of the MERLIN programme was to investigate the extent of sub-channel blockage produced during clad deformation under conditions of high mechanical restraint, in two phase cooling conditions. The programme was to consist of four test bundles, the final two of which would be used for ballooning experiments in which high sub-channel blockage would be produced by a suitable choice of test conditions. A major part of the programme was to provide validation data for reactor accident codes used in the CEGB clad ballooning safety case for Sizewell B. This report, one of a series which describes the programme in detail, is an overview of the MERLIN programme. It provides background, summarises those reports which discuss the programme in detail and draws attention to those areas where useful information has been obtained. (author)

  13. Flat acoustic lens by acoustic grating with curled slits

    KAUST Repository

    Peng, Pai

    2014-10-01

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry-Perot resonance.

  14. Acoustic energy harvesting based on a planar acoustic metamaterial

    Science.gov (United States)

    Qi, Shuibao; Oudich, Mourad; Li, Yong; Assouar, Badreddine

    2016-06-01

    We theoretically report on an innovative and practical acoustic energy harvester based on a defected acoustic metamaterial (AMM) with piezoelectric material. The idea is to create suitable resonant defects in an AMM to confine the strain energy originating from an acoustic incidence. This scavenged energy is converted into electrical energy by attaching a structured piezoelectric material into the defect area of the AMM. We show an acoustic energy harvester based on a meta-structure capable of producing electrical power from an acoustic pressure. Numerical simulations are provided to analyze and elucidate the principles and the performances of the proposed system. A maximum output voltage of 1.3 V and a power density of 0.54 μW/cm3 are obtained at a frequency of 2257.5 Hz. The proposed concept should have broad applications on energy harvesting as well as on low-frequency sound isolation, since this system acts as both acoustic insulator and energy harvester.

  15. Acoustics Discipline Overview

    Science.gov (United States)

    Envia, Edmane; Thomas, Russell

    2007-01-01

    As part of the Fundamental Aeronautics Program Annual Review, a summary of the progress made in 2007 in acoustics research under the Subsonic Fixed Wing project is given. The presentation describes highlights from in-house and external activities including partnerships and NRA-funded research with industry and academia. Brief progress reports from all acoustics Phase 1 NRAs are also included as are outlines of the planned activities for 2008 and all Phase 2 NRAs. N+1 and N+2 technology paths outlined for Subsonic Fixed Wing noise targets. NRA Round 1 progressing with focus on prediction method advancement. NRA Round 2 initiating work focused on N+2 technology, prediction methods, and validation. Excellent partnerships in progress supporting N+1 technology targets and providing key data sets.

  16. Acoustic Tractor Beam

    Science.gov (United States)

    Démoré, Christine E. M.; Dahl, Patrick M.; Yang, Zhengyi; Glynne-Jones, Peter; Melzer, Andreas; Cochran, Sandy; MacDonald, Michael P.; Spalding, Gabriel C.

    2014-05-01

    Negative radiation forces act opposite to the direction of propagation, or net momentum, of a beam but have previously been challenging to definitively demonstrate. We report an experimental acoustic tractor beam generated by an ultrasonic array operating on macroscopic targets (>1 cm) to demonstrate the negative radiation forces and to map out regimes over which they dominate, which we compare to simulations. The result and the geometrically simple configuration show that the effect is due to nonconservative forces, produced by redirection of a momentum flux from the angled sides of a target and not by conservative forces from a potential energy gradient. Use of a simple acoustic setup provides an easily understood illustration of the negative radiation pressure concept for tractor beams and demonstrates continuous attraction towards the source, against a net momentum flux in the system.

  17. Acoustic absorption by sunspots

    Science.gov (United States)

    Braun, D. C.; Labonte, B. J.; Duvall, T. L., Jr.

    1987-01-01

    The paper presents the initial results of a series of observations designed to probe the nature of sunspots by detecting their influence on high-degree p-mode oscillations in the surrounding photosphere. The analysis decomposes the observed oscillations into radially propagating waves described by Hankel functions in a cylindrical coordinate system centered on the sunspot. From measurements of the differences in power between waves traveling outward and inward, it is demonstrated that sunspots appear to absorb as much as 50 percent of the incoming acoustic waves. It is found that for all three sunspots observed, the amount of absorption increases linearly with horizontal wavenumber. The effect is present in p-mode oscillations with wavelengths both significantly larger and smaller than the diameter of the sunspot umbrae. Actual absorption of acoustic energy of the magnitude observed may produce measurable decreases in the power and lifetimes of high-degree p-mode oscillations during periods of high solar activity.

  18. Acoustic absorption by sunspots

    Energy Technology Data Exchange (ETDEWEB)

    Braun, D.C.; Labonte, B.J.; Duvall, T.L. Jr.

    1987-08-01

    The paper presents the initial results of a series of observations designed to probe the nature of sunspots by detecting their influence on high-degree p-mode oscillations in the surrounding photosphere. The analysis decomposes the observed oscillations into radially propagating waves described by Hankel functions in a cylindrical coordinate system centered on the sunspot. From measurements of the differences in power between waves traveling outward and inward, it is demonstrated that sunspots appear to absorb as much as 50 percent of the incoming acoustic waves. It is found that for all three sunspots observed, the amount of absorption increases linearly with horizontal wavenumber. The effect is present in p-mode oscillations with wavelengths both significantly larger and smaller than the diameter of the sunspot umbrae. Actual absorption of acoustic energy of the magnitude observed may produce measurable decreases in the power and lifetimes of high-degree p-mode oscillations during periods of high solar activity. 10 references.

  19. Norwegian mastitis control programme

    Directory of Open Access Journals (Sweden)

    Østerås O

    2009-04-01

    changes in attitude and breeding, eradicating bovine virus diarrhoea virus (BVDV and a better implementation of mastitis prevention programmes.

  20. Acoustic Method for Testing the Quality of Sterilized Male Tsetse Flies Glossina Pallidipes

    International Nuclear Information System (INIS)

    Tsetse flies are able to emit different acoustic signals. An acoustic method to test the quality of sterilized male tsetse flies was developed. Differences in the sound characteristics between males and females, between sterilized and unsterilized males, and between males sterilized in air and nitrogen, were determined. Also, the acoustic parameters (frequency, time, sound pressure level) of the sounds that are useful as criteria for quality control were determined. It was demonstrated that only the so-called 'feeding sounds' can be used as a quality criterion. Both sexes emitted feeding sounds while feeding on a host. These sounds were also used to find sexual partners, and had an effect on male copulation success. An acoustic sound analysis programme was developed; it automatically measured sound activity (only feeding sounds) under standard conditions (random sample, relative humidity, temperature, light intensity). (author)

  1. Acoustic emission source modeling

    Directory of Open Access Journals (Sweden)

    Hora P.

    2010-07-01

    Full Text Available The paper deals with the acoustic emission (AE source modeling by means of FEM system COMSOL Multiphysics. The following types of sources are used: the spatially concentrated force and the double forces (dipole. The pulse excitation is studied in both cases. As a material is used steel. The computed displacements are compared with the exact analytical solution of point sources under consideration.

  2. The acoustics of snoring.

    Science.gov (United States)

    Pevernagie, Dirk; Aarts, Ronald M; De Meyer, Micheline

    2010-04-01

    Snoring is a prevalent disorder affecting 20-40% of the general population. The mechanism of snoring is vibration of anatomical structures in the pharyngeal airway. Flutter of the soft palate accounts for the harsh aspect of the snoring sound. Natural or drug-induced sleep is required for its appearance. Snoring is subject to many influences such as body position, sleep stage, route of breathing and the presence or absence of sleep-disordered breathing. Its presentation may be variable within or between nights. While snoring is generally perceived as a social nuisance, rating of its noisiness is subjective and, therefore, inconsistent. Objective assessment of snoring is important to evaluate the effect of treatment interventions. Moreover, snoring carries information relating to the site and degree of obstruction of the upper airway. If evidence for monolevel snoring at the site of the soft palate is provided, the patient may benefit from palatal surgery. These considerations have inspired researchers to scrutinize the acoustic characteristics of snoring events. Similarly to speech, snoring is produced in the vocal tract. Because of this analogy, existing techniques for speech analysis have been applied to evaluate snoring sounds. It appears that the pitch of the snoring sound is in the low-frequency range (noise-like', and has scattered energy content in the higher spectral sub-bands (>500 Hz). To evaluate acoustic properties of snoring, sleep nasendoscopy is often performed. Recent evidence suggests that the acoustic quality of snoring is markedly different in drug-induced sleep as compared with natural sleep. Most often, palatal surgery alters sound characteristics of snoring, but is no cure for this disorder. It is uncertain whether the perceived improvement after palatal surgery, as judged by the bed partner, is due to an altered sound spectrum. Whether some acoustic aspects of snoring, such as changes in pitch, have predictive value for the presence of

  3. Acoustically enhanced heat transport

    Energy Technology Data Exchange (ETDEWEB)

    Ang, Kar M.; Hung, Yew Mun; Tan, Ming K., E-mail: tan.ming.kwang@monash.edu [School of Engineering, Monash University Malaysia, 47500 Bandar Sunway, Selangor (Malaysia); Yeo, Leslie Y. [Micro/Nanophysics Research Laboratory, RMIT University, Melbourne, VIC 3001 (Australia); Friend, James R. [Department of Mechanical and Aerospace Engineering, University of California, San Diego, California 92093 (United States)

    2016-01-15

    We investigate the enhancement of heat transfer in the nucleate boiling regime by inducing high frequency acoustic waves (f ∼ 10{sup 6} Hz) on the heated surface. In the experiments, liquid droplets (deionized water) are dispensed directly onto a heated, vibrating substrate. At lower vibration amplitudes (ξ{sub s} ∼ 10{sup −9} m), the improved heat transfer is mainly due to the detachment of vapor bubbles from the heated surface and the induced thermal mixing. Upon increasing the vibration amplitude (ξ{sub s} ∼ 10{sup −8} m), the heat transfer becomes more substantial due to the rapid bursting of vapor bubbles happening at the liquid-air interface as a consequence of capillary waves travelling in the thin liquid film between the vapor bubble and the air. Further increases then lead to rapid atomization that continues to enhance the heat transfer. An acoustic wave displacement amplitude on the order of 10{sup −8} m with 10{sup 6} Hz order frequencies is observed to produce an improvement of up to 50% reduction in the surface temperature over the case without acoustic excitation.

  4. Acoustics, computers and measurements

    Science.gov (United States)

    Truchard, James J.

    2003-10-01

    The human ear has created a high standard for the requirements of acoustical measurements. The transient nature of most acoustical signals has limited the success of traditional volt meters. Professor Hixson's pioneering work in electroacoustical measurements at ARL and The University of Texas helped set the stage for modern computer-based measurements. The tremendous performance of modern PCs and extensive libraries of signal processing functions in virtual instrumentation application software has revolutionized the way acoustical measurements are made. Today's analog to digital converters have up to 24 bits of resolution with a dynamic range of over 120 dB and a single PC processor can process 112 channels of FFTs at 4 kHz in real time. Wavelet technology further extends the capabilities for analyzing transients. The tools available for measurements in speech, electroacoustics, noise, and vibration represent some of the most advanced measurement tools available. During the last 50 years, Professor Hixson has helped drive this revolution from simple oscilloscope measurements to the modern high performance computer-based measurements.

  5. Fundamentals of Shallow Water Acoustics

    CERN Document Server

    Katsnelson, Boris; Lynch, James

    2012-01-01

    Shallow water acoustics (SWA), the study of how low and medium frequency sound propagates and scatters on the continental shelves of the world's oceans, has both technical interest and a large number of practical applications. Technically, shallow water poses an interesting medium for the study of acoustic scattering, inverse theory, and propagation physics in a complicated oceanic waveguide. Practically, shallow water acoustics has interest for geophysical exploration, marine mammal studies, and naval applications. Additionally, one notes the very interdisciplinary nature of shallow water acoustics, including acoustical physics, physical oceanography, marine geology, and marine biology. In this specialized volume, the authors, all of whom have extensive at-sea experience in U.S. and Russian research efforts, have tried to summarize the main experimental, theoretical, and computational results in shallow water acoustics, with an emphasis on providing physical insight into the topics presented.

  6. Latest Trends in Acoustic Sensing

    Directory of Open Access Journals (Sweden)

    Cinzia Caliendo

    2014-03-01

    Full Text Available Acoustics-based methods offer a powerful tool for sensing applications. Acoustic sensors can be applied in many fields ranging from materials characterization, structural health monitoring, acoustic imaging, defect characterization, etc., to name just a few. A proper selection of the acoustic wave frequency over a wide spectrum that extends from infrasound (<20 Hz up to ultrasound (in the GHz–band, together with a number of different propagating modes, including bulk longitudinal and shear waves, surface waves, plate modes, etc., allow acoustic tools to be successfully applied to the characterization of gaseous, solid and liquid environments. The purpose of this special issue is to provide an overview of the research trends in acoustic wave sensing through some cases that are representative of specific applications in different sensing fields.

  7. High-Frequency Seafloor Acoustics

    CERN Document Server

    Jackson, Darrell R

    2007-01-01

    High-Frequency Seafloor Acoustics is the first book in a new series sponsored by the Office of Naval Research on the latest research in underwater acoustics. This exciting new title provides ready access to experimental data, theory, and models relevant to high-frequency seafloor acoustics and will be of interest to sonar engineers and researchers working in underwater acoustics. The physical characteristics of the seafloor affecting acoustic propagation and scattering are covered, including physical and geoacoustic properties and surface roughness. Current theories for acoustic propagation in sediments are presented along with corresponding models for reflection, scattering, and seafloor penetration. The main text is backed up by an extensive bibliography and technical appendices.

  8. Early diagnosis of acoustic neuroma by the vestibular test

    Energy Technology Data Exchange (ETDEWEB)

    Haid, T.; Rettinger, G.; Berg, M.; Wigand, M.E.

    1981-11-01

    In a series of 390 cases with suspicion of acoustic neurinomas 78 such tumors could be diagnosed, including 12 early stage neurinomas. This relatively high detection quote of small neurinomas is due to a special diagnostical programme: Every patient with unilateral and sensoneural hearingloss, independent of vertigo anamnesis or of the result of X-rays must be further examined by a vestibular test. All 78 patients with acoustic neuroma had pathological vestibular findings. The positional test turned out to be the most sensitive examination in the early diagnosis of acoustic neuromas and yields a still higher incidence than the thermic test: 95% of the patients with a neuroma showed pathological findings in the positional test. Every patient suffering from an unidentified unilateral and sensoneural hearingloss combined with a pathological result in the positional test must be further checked by a cisternomeatography or computerized tomography using airinsufflation. Every fifth of these patients showed typical signs of an acoustic neuroma in the neuroradiological tests. 68 neuromas are operated today and verfied histologically, 10 patients are still waiting for surgical treatment.

  9. Assessing the Financial Viability of Academic Programmes

    Science.gov (United States)

    Swift, Lynette

    2012-01-01

    This paper reviews and examines approaches to determining the financial viability of academic programmes as a critical component of assessing a programme's overall sustainability. Key to assessing the financial viability of a programme is understanding the teaching activities required to deliver the programme and the cost of those activities. A…

  10. Acoustical coupling of lizard eardrums

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, Jakob; Manley, Geoffrey A

    2008-01-01

    Lizard ears are clear examples of two-input pressure-difference receivers, with up to 40-dB differences in eardrum vibration amplitude in response to ipsi- and contralateral stimulus directions. The directionality is created by acoustical coupling of the eardrums and interaction of the direct...... is caused by the acoustic interaction of the two eardrums. The results can be largely explained by a simple acoustical model based on an electrical analog circuit....

  11. Room acoustic auralization with Ambisonics

    OpenAIRE

    Polack, Jean-Dominique; Leão Figueiredo, Fábio

    2012-01-01

    International audience During the year of 2009, the room acoustics group of the LAM (Équipe Lutheries, Acoustique, Musique de l’Institut Jean Le Rond d’Alembert - Université Pierre et Marie Curie, Paris) performed a series of acoustical measurements in music halls in Paris. The halls were chosen in regarding their importance to the historic, architectural or acoustic domains. The measured ensemble of fourteen rooms includes quite different architectural designs. The measurements were carri...

  12. Combined Environment Acoustic Chamber (CEAC)

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The CEAC imposes combined acoustic, thermal and mechanical loads on aerospace structures. The CEAC is employed to measure structural response and determine...

  13. New Euratom research programme 2002-2006

    Energy Technology Data Exchange (ETDEWEB)

    Mustonen, R. [Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2003-06-01

    The European Union funded research is carried out under two distinct programmes; the European Community Framework Programme (EC Programme) covering research, technological development and demonstration activities; and the Euratom Framework Programme covering research and training activities in the nuclear sector. The contents, funding and timetable of the sixth Euratom Framework Programme (FP6) are shortly reviewed in this paper. The European Union (EU) FP6 for the years 2002 - 2006 starts at the beginning of the year 2003.

  14. Feedback control of acoustic musical instruments: collocated control using physical analogs.

    Science.gov (United States)

    Berdahl, Edgar; Smith, Julius O; Niemeyer, Günter

    2012-01-01

    Traditionally, the average professional musician has owned numerous acoustic musical instruments, many of them having distinctive acoustic qualities. However, a modern musician could prefer to have a single musical instrument whose acoustics are programmable by feedback control, where acoustic variables are estimated from sensor measurements in real time and then fed back in order to influence the controlled variables. In this paper, theory is presented that describes stable feedback control of an acoustic musical instrument. The presentation should be accessible to members of the musical acoustics community who may have limited or no experience with feedback control. First, the only control strategy guaranteed to be stable subject to any musical instrument mobility is described: the sensors and actuators must be collocated, and the controller must emulate a physical analog system. Next, the most fundamental feedback controllers and the corresponding physical analog systems are presented. The effects that these controllers have on acoustic musical instruments are described. Finally, practical design challenges are discussed. A proof explains why changing the resonance frequency of a musical resonance requires much more control power than changing the decay time of the resonance.

  15. Evaluation of the FWF Doctoral Programme (DK Programme)

    OpenAIRE

    Ecker, Brigitte; Kottmann, Andrea; Meyer, Susanne; Brandl, Bianca

    2014-01-01

    In the winter term 2013 a total of 27,634 doctoral students were enrolled at Austrian universities and a total of 2,165 students obtained a doctoral degree; thereof 204 (9.4%) students graduated in a PhD Programme. In total 7,158 doctoral students were employed at Austrian universities in 2012. These numbers include those doctoral students with temporary positions who were funded by competitive means, as provided by the funding programmes of the FWF. In total the FWF as the most important fun...

  16. Programmable automation systems in PSA

    International Nuclear Information System (INIS)

    The Finnish safety authority (STUK) requires plant specific PSAs, and quantitative safety goals are set on different levels. The reliability analysis is more problematic when critical safety functions are realized by applying programmable automation systems. Conventional modeling techniques do not necessarily apply to the analysis of these systems, and the quantification seems to be impossible. However, it is important to analyze contribution of programmable automation systems to the plant safety and PSA is the only method with system analytical view over the safety. This report discusses the applicability of PSA methodology (fault tree analyses, failure modes and effects analyses) in the analysis of programmable automation systems. The problem of how to decompose programmable automation systems for reliability modeling purposes is discussed. In addition to the qualitative analysis and structural reliability modeling issues, the possibility to evaluate failure probabilities of programmable automation systems is considered. One solution to the quantification issue is the use of expert judgements, and the principles to apply expert judgements is discussed in the paper. A framework to apply expert judgements is outlined. Further, the impacts of subjective estimates on the interpretation of PSA results are discussed. (orig.) (13 refs.)

  17. Flexible Programmes in Higher Professional Education: Expert Validation of a Flexible Educational Model

    Science.gov (United States)

    Schellekens, Ad; Paas, Fred; Verbraeck, Alexander; van Merrienboer, Jeroen J. G.

    2010-01-01

    In a preceding case study, a process-focused demand-driven approach for organising flexible educational programmes in higher professional education (HPE) was developed. Operations management and instructional design contributed to designing a flexible educational model by means of discrete-event simulation. Educational experts validated the model…

  18. Comparison of programme MOBY-DICK with nodal programmes on benchmark problems

    International Nuclear Information System (INIS)

    In this paper we compare programme MOBY-DICK (which is diffusion difference programme) with nodal programmes no two-dimensional hexagonal benchmark problems for the VVER-type reactors (published by Chao and Shatilla). Nodal results are partly from one's own programme NODRAM and partly from literature. There is presented dependence on lattice pitch by difference programme and influence of boundary conditions (Author)

  19. Influence of thermal inhibitor position and temperature on vortex-shedding-driven pressure oscillations

    Institute of Scientific and Technical Information of China (English)

    Su Wanxing; Li Shipeng; Zhang Qiao; Li Junwei; Ye Qingqing; Wang Ningfei

    2013-01-01

    Vortex-acoustic coupling is one of the most important potential sources of combustion instability in solid rocket motors (SRMs).Based on the Von Karman Institute for Fluid Dynamics (VKI) experimental motor,the influence of the thermal inhibitor position and temperature on vortex-shedding-driven pressure oscillations is numerically studied via the large eddy simulation (LES)method.The simulation results demonstrate that vortex shedding is a periodic process and its accurate frequency can be numerically obtained.Acoustic modes could be easily excited by vortex shedding.The vortex shedding frequency and second acoustic frequency dominate the pressure oscillation characteristics in the chamber.Thermal inhibitor position and gas temperature have little effect on vortex shedding frequency,but have great impact on pressure oscillation amplitude.Pressure amplitude is much higher when the thermal inhibitor locates at the acoustic velocity anti-nodes.The farther the thermal inhibitor is to the nozzle head,the more vortex energy would be dissipated by the turbulence.Therefore,the vortex shedding amplitude at the second acoustic velocity antinode near 3/4L (L is chamber length) is larger than those of others.Besides,the natural acoustic frequencies increase with the gas temperature.As the vortex shedding frequency departs from the natural acoustic frequency,the vortex-acoustic feedback loop is decoupled.Consequently,both the vortex shedding and acoustic amplitudes decrease rapidly.

  20. Acoustic charge transport technology investigation for advanced development transponder

    Science.gov (United States)

    Kayalar, S.

    1993-01-01

    Acoustic charge transport (ACT) technology has provided a basis for a new family of analog signal processors, including a programmable transversal filter (PTF). Through monolithic integration of ACT delay lines with GaAs metal semiconductor field effect transistor (MESFET) digital memory and controllers, these devices significantly extend the performance of PTF's. This article introduces the basic operation of these devices and summarizes their present and future specifications. The production and testing of these devices indicate that this new technology is a promising one for future space applications.

  1. The various programmes within the EU

    International Nuclear Information System (INIS)

    Partitioning and transmutation aims at reducing the amount of minor actinides, and thus the radiotoxicity of the high level waste going to disposal. One way to handle minor actinides is to concentrate them in a specific stratum using systems which are dedicated to transmutation. The subcritical systems known as hybrid systems or Accelerator Driven Systems (ADS) are able to burn these actinides at a high level of concentration in the core. The development of ADS for radioactive waste transmutation is envisaged from the mid-1990s in a European context under the encouragement of Professor Carlo Rubbia. This development aims at placing the role of ADS within a double strata fuel cycle strategy. The roadmap includes several years of R&D on the acquisition of the physical and technological data needed for the operation of a fast neutron ADS. During the 5th Framework programme, from 2000 to 2004, the MUSE experiments were realized in the MASURCA facility of the CEA-CADARACHE. After MUSE, and in the frame of the 6th Framework programme running now, researches in this domain are mainly focused on five topics: – Qualification of subcriticality monitoring; – Validation of the core power-beam current relationship; – Startup and shutdown procedures, instrumentation validation and specific dedicated experimentation; – Interpretation and validation of experimental data, benchmarking and code validation activities; – Safety and licensing issues of different components and for the integrated system. New experiments named: RACE-T in the TRIGA reactor of ENEA-CASACCIA, RACE-LP-IAC in the subcritical assembly of the Idaho Accelerator Center in US, YALINA in the subcritical assembly of MINSK in BELARUS, and the new proposal GUINEVERE in the VENUS reactor of SCK•CEN are supported. On following, after the recall of the MUSE main results, the outlines of these experiments and the main results when available are reported

  2. Analog circuit for controlling acoustic transducer arrays

    Energy Technology Data Exchange (ETDEWEB)

    Drumheller, Douglas S. (Cedar Crest, NM)

    1991-01-01

    A simplified ananlog circuit is presented for controlling electromechanical transducer pairs in an acoustic telemetry system. The analog circuit of this invention comprises a single electrical resistor which replaces all of the digital components in a known digital circuit. In accordance with this invention, a first transducer in a transducer pair of array is driven in series with the resistor. The voltage drop across this resistor is then amplified and used to drive the second transducer. The voltage drop across the resistor is proportional and in phase with the current to the transducer. This current is approximately 90 degrees out of phase with the driving voltage to the transducer. This phase shift replaces the digital delay required by the digital control circuit of the prior art.

  3. Geodesic Acoustic Modes Induced by Energetic Particles

    Science.gov (United States)

    Zhou, Tianchun; Berk, Herbert

    2009-11-01

    A global geodesic acoustic mode driven by energetic particles (EGAM) has been observed in JET[1, 2] and DIII D[3, 4]. The mode is to be treated fully kinetically. The descriptions of the background electrons and ions are based on standard high and low bounce frequency expansion respectively with respect to the mode frequency. However, the energetic ions must be treated without any expansion of ratio between their bounce frequency and the mode frequency since they are comparable. Under electrostatic perturbation, we construct a quadratic form for the wave amplitude, from which an integro-differential equation is derived. In the limit where the drift orbit width is small comparison with the mode width, a differential equation for perturbed electrostatic field is obtained. Solution is obtained both analytically and numerically. We find that beam counterinjection enhances the instability of the mode. Landau damping due to thermal species is investigated.

  4. Acoustic transparency and slow sound using detuned acoustic resonators

    DEFF Research Database (Denmark)

    Santillan, Arturo Orozco; Bozhevolnyi, Sergey I.

    2011-01-01

    We demonstrate that the phenomenon of acoustic transparency and slowsound propagation can be realized with detuned acoustic resonators (DAR), mimicking thereby the effect of electromagnetically induced transparency (EIT) in atomic physics. Sound propagation in a pipe with a series of side...

  5. A heat-driven thermoacoustic cryocooler capable of reaching below liquid hydrogen temperature

    Institute of Scientific and Technical Information of China (English)

    HU JianYing; LUO ErCang; DAI Wei; Zhou Yuan

    2007-01-01

    A "double-gas acoustic amplifier" is introduced to couple a thermoacoustic heat engine and a two-stage pulse tube cooler in this paper. Compared with previous acoustic amplifiers, this new acoustic amplifier maintains the function of amplification for pressure amplitude. In particular, the novel acoustic amplifier with a reservoir makes it possible to install an acoustic transparent but gas blocking elastic membrane between the engine and the cooler. Thus, the engine can use nitrogen as the working gas to work at low frequency; and meanwhile, the cooler can still use helium as the working gas to maintain its high performance. With this new amplifier, the cooling temperature of a two-stage pulse tube cooler driven by an energy-focused thermoacoustic engine reached 18.7 K.

  6. Radon programmes and health marketing.

    Science.gov (United States)

    Fojtikova, Ivana; Rovenska, Katerina

    2011-05-01

    Being aware of negative health effects of radon exposure, many countries aim for the reduction of the radon exposure of their population. The Czech radon programme was commenced >20 y ago. Since then experts have gathered a lot of knowledge, necessary legislation has been enacted, tens of thousands of inhabitants have been offered free measurement and subsidy for the mitigation. Despite the effort, the effectiveness of the radon programme seems to be poor. Newly built houses still exhibit elevated radon concentrations and the number of houses mitigated is very low. Is it possible to enhance the effectivity of radon programme while keeping it on a voluntary basis? One possible way is to employ health marketing that draws together traditional marketing theories and science-based strategies to prevention. The potential of using marketing principles in communication and delivery of radon information will be discussed. PMID:21498864

  7. Energy Management Programmes for Industry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-09-05

    The IEA Policy Pathway publications provide details on how to implement specific recommendations drawn from the IEA 25 Energy Efficiency Policy Recommendations. This Policy Pathway, jointly produced by the International Energy Agency and the Institute for Industrial Productivity, develops the critical steps for policy makers implementing energy management programmes for industry. Optimising energy use in industry is essential to improve industrial competitiveness and achieve wider societal goals such as energy security, economic recovery and development, climate change mitigation and environmental protection. While there is significant potential to decrease energy consumption in this sector, opportunities to improve energy efficiency are still under-exploited. Energy management programmes have shown to be instrumental in addressing many of the barriers that inhibit wide-scale uptake of energy management in industry. The Policy Pathway builds on lessons learned from country experiences and provides actionable guidance on how to plan and design, implement, evaluate and monitor energy management programmes for industry.

  8. Strategising for the future Indian EO programme

    Science.gov (United States)

    Rao, Mukund; Jayaraman, V.; Kalyanraman, S.; Joseph, George; Navalgund, R. R.; Kasturirangan, K.

    2002-07-01

    The Indian Earth Observations Program, over the past three decades, has been mainly driven by the national need of natural resources management, infrastructure development, environment monitoring and disaster management support. With an array of seven Indian Remote Sensing Satellites (IRS), national development support has been supported, through a well-knit institutional framework of a National Natural Resources Management System (NNRMS), a wide variety of applications developed as an inter-agency effort over the past 20 years. Now, the capacity of the programme has been extended into the global arena and IRS is providing operational data services to the global user community. The future Earth Observation Systems will have to take into consideration the aspects related to the commercialisation and standardisation of programmes world-over; transitioning into a business environment; data continuity and the need to monitor processes rather than events. Technological changes are also going to re-define many of the concepts of observation from space and issues like spatial resolution, spectral resolution and temporal resolution may no more be a concern for observation systems. ISRO is presently defining a strategy for the Indian EO Programme that will chart the progress with a vision for the next 25 years. Based on a thorough analysis, the observation needs of the future are planned and presently systems design and implementation are underway. The Need Analysis has been done keeping in mind the Global change applications; Mapping and Cartographic applications; Natural Resources and Environmental management applications etc. Issues related to defining the space and data acquisition as a national "public good", costing of data products and services and evolving a commercial remote sensing policy have been addressed for providing the overall thrust of the Indian Earth Observations program. The paper discusses the strategy adopted for assessing the future user requirements

  9. Acoustic Mechanical Feedthroughs

    Science.gov (United States)

    Sherrit, Stewart; Walkemeyer, Phillip; Bao, Xiaoqi; Bar-Cohen, Yoseph; Badescu, Mircea

    2013-01-01

    Electromagnetic motors can have problems when operating in extreme environments. In addition, if one needs to do mechanical work outside a structure, electrical feedthroughs are required to transport the electric power to drive the motor. In this paper, we present designs for driving rotary and linear motors by pumping stress waves across a structure or barrier. We accomplish this by designing a piezoelectric actuator on one side of the structure and a resonance structure that is matched to the piezoelectric resonance of the actuator on the other side. Typically, piezoelectric motors can be designed with high torques and lower speeds without the need for gears. One can also use other actuation materials such as electrostrictive, or magnetostrictive materials in a benign environment and transmit the power in acoustic form as a stress wave and actuate mechanisms that are external to the benign environment. This technology removes the need to perforate a structure and allows work to be done directly on the other side of a structure without the use of electrical feedthroughs, which can weaken the structure, pipe, or vessel. Acoustic energy is pumped as a stress wave at a set frequency or range of frequencies to produce rotary or linear motion in a structure. This method of transferring useful mechanical work across solid barriers by pumping acoustic energy through a resonant structure features the ability to transfer work (rotary or linear motion) across pressure or thermal barriers, or in a sterile environment, without generating contaminants. Reflectors in the wall of barriers can be designed to enhance the efficiency of the energy/power transmission. The method features the ability to produce a bi-directional driving mechanism using higher-mode resonances. There are a variety of applications where the presence of a motor is complicated by thermal or chemical environments that would be hostile to the motor components and reduce life and, in some instances, not be

  10. Taming Acoustic Cavitation

    CERN Document Server

    Rivas, David Fernandez; Enriquez, Oscar R; Versluis, Michel; Prosperetti, Andrea; Gardeniers, Han; Lohse, Detlef

    2012-01-01

    In this fluid dynamics video we show acoustic cavitation occurring from pits etched on a silicon surface. By immersing the surface in a liquid, gas pockets are entrapped in the pits which upon ultrasonic insonation, are observed to shed cavitation bubbles. Modulating the driving pressure it is possible to induce different behaviours based on the force balance that determines the interaction among bubbles and the silicon surface. This system can be used for several applications like sonochemical water treatment, cleaning of surfaces with deposited materials such as biofilms.

  11. Lecture Notes On Acoustics

    International Nuclear Information System (INIS)

    This book mentions string vibration and wave, one-dimension wave and wave equation, characteristic impedance, governing equation of string, and wave energy from string, wave equation of wave and basic physical quantity like one-dimension wave equation, sound unit, sound intensity and energy, sound movement in a surface of discontinuity with transmission loss of sound by partition, and Snell's law, radiation, scatter and diffraction and sound in closed space with Sabine's theory, sound characteristic of closed space and duct acoustics.

  12. Dynamic acoustic tractor beams

    Energy Technology Data Exchange (ETDEWEB)

    Mitri, F. G., E-mail: F.G.Mitri@ieee.org [Chevron, Area 52 Technology – ETC, Santa Fe, New Mexico 87508 (United States)

    2015-03-07

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  13. Dynamic acoustic tractor beams

    Science.gov (United States)

    Mitri, F. G.

    2015-03-01

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  14. British Energy Operating Experience Programme

    International Nuclear Information System (INIS)

    British Energy is the major nuclear generator in the U.K. It has a market share varying between 22% and 25% of the total U.K. generation. The fleet of power stations operated by British Energy consists of one 1250 MWe Pressurised Water Reactor, six Advanced Gas Cooled reactor sites, each with two reactor units of 660 MWe, and one coal fired site with four units of 500 Mwe. In early 1999 British Energy set a strategic goal, for all its reactor units, to achieve 'World Class Performance through Cost leadership' by the end of year 2004. This would be measured against the applicable Upper Quartile performance indicators of the World Association of Nuclear Operators (WANO). Against this strategic goal six fundamental objectives were identified, one of which was to define, deploy and measure the effectiveness of a world class Operating Experience programme. British Energy has clearly re-defined its Operating Experience programme and, recognised the value of learning from Operating Experience. Commitment to the programme, and communicating the value of an effective OE programme is being clearly demonstrated by all managers throughout the organisation. Making the information easily accessible at the workplace has been achieved via the British Energy intranet, the harder step is to ensure OE is consulted before commencing an assigned task or plant evolution. Early signs of this are encouraging, but a continuous sustained effort will be required for probably the next two years. The full deployment of the OE programme is scheduled to be complete by 2004. There will however be a redefined programme identified by then to incorporate the lessons learnt and to ensure the programme is aligned with the business as it evolves. An analysis of event root causes and precursors since May 2001 will be undertaken in June 2002. These will be compared with data from previous years to ascertain the effect on the number of recurring events. The critical question, 'has this prevented recurring

  15. Algorithmique et langages de programmation

    OpenAIRE

    Arsac, Jacques

    1991-01-01

    Dans les débuts de l'informatique, un cours de programmation consistait essentiellement en une description des organigrammes, comme représentation graphique de la structure d'un programme (tellement embrouillée qu'il fallait bien en passer par là), et la liste des instructions d'un langage : les constantes entières s'écrivent avec des chiffres sans point décimal ni partie exposant, un identificateur... l'instruction LIRE, etc. Pour le reste, l'apprenti programmeur devait se débrouiller tout s...

  16. Accelerator Neutrino Programme at FERMILAB

    International Nuclear Information System (INIS)

    The accelerator neutrino programme in the USA consists primarily of the Fermilab neutrino programme. Currently, Fermilab operates two neutrino beamlines, the Booster neutrino beamline and the NuMI neutrino beamline and is the planning stages for a third neutrino beam to send neutrinos to DUSEL. The experiments in the Booster neutrino beamline are miniBooNE, SciBooNE and in the future microBooNE, whereas in the NuMI beamline we have MINOS, ArgoNut, MINERVA and coming soon NOA. The major experiment in the beamline to DUSEL will be LBNE. (author)

  17. The ESO Observing Programmes Committee

    Science.gov (United States)

    Westerlund, B. E.

    1982-06-01

    Since 1978 the ESO Observing Programmes Committee (OPC) has "the function to inspect and rank the proposals made for observing programmes at La Silla, and thereby to advise the Director General on the distribution of observing time". The members (one from each member country) and their alternates are nominated by the respective national committees for five-year terms (not immediately renewable). The terms are staggered so that each year one or two persons are replaced. The Chairman is appointed annually by the Council. He is invited to attend Council meetings and to report to its members.

  18. Acoustic Similarity and Dichotic Listening.

    Science.gov (United States)

    Benson, Peter

    1978-01-01

    An experiment tests conjectures that right ear advantage (REA) has an auditory origin in competition or interference between acoustically similar stimuli and that feature-sharing effect (FSE) has its origin in assignment of features of phonetically similar stimuli. No effect on the REA for acoustic similarity, and a clear effect of acoustic…

  19. Acoustic Center or Time Origin?

    DEFF Research Database (Denmark)

    Staffeldt, Henrik

    1999-01-01

    The paper discusses the acoustic center in relation to measurements of loudspeaker polar data. Also, it presents the related concept time origin and discusses the deviation that appears between positions of the acoustic center found by wavefront based and time based measuring methods....

  20. Digital Controller For Acoustic Levitation

    Science.gov (United States)

    Tarver, D. Kent

    1989-01-01

    Acoustic driver digitally controls sound fields along three axes. Allows computerized acoustic levitation and manipulation of small objects for such purposes as containerless processing and nuclear-fusion power experiments. Also used for controlling motion of vibration-testing tables in three dimensions.

  1. Propagation of Ion Acoustic Perturbations

    DEFF Research Database (Denmark)

    Pécseli, Hans

    1975-01-01

    Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered.......Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered....

  2. Aero-acoustics of Drag Generating Swirling Exhaust Flows

    Science.gov (United States)

    Shah, P. N.; Mobed, D.; Spakovszky, Z. S.; Brooks, T. F.; Humphreys, W. M. Jr.

    2007-01-01

    Aircraft on approach in high-drag and high-lift configuration create unsteady flow structures which inherently generate noise. For devices such as flaps, spoilers and the undercarriage there is a strong correlation between overall noise and drag such that, in the quest for quieter aircraft, one challenge is to generate drag at low noise levels. This paper presents a rigorous aero-acoustic assessment of a novel drag concept. The idea is that a swirling exhaust flow can yield a steady, and thus relatively quiet, streamwise vortex which is supported by a radial pressure gradient responsible for pressure drag. Flows with swirl are naturally limited by instabilities such as vortex breakdown. The paper presents a first aero-acoustic assessment of ram pressure driven swirling exhaust flows and their associated instabilities. The technical approach combines an in-depth aerodynamic analysis, plausibility arguments to qualitatively describe the nature of acoustic sources, and detailed, quantitative acoustic measurements using a medium aperture directional microphone array in combination with a previously established Deconvolution Approach for Mapping of Acoustic Sources (DAMAS). A model scale engine nacelle with stationary swirl vanes was designed and tested in the NASA Langley Quiet Flow Facility at a full-scale approach Mach number of 0.17. The analysis shows that the acoustic signature is comprised of quadrupole-type turbulent mixing noise of the swirling core flow and scattering noise from vane boundary layers and turbulent eddies of the burst vortex structure near sharp edges. The exposed edges are the nacelle and pylon trailing edge and the centerbody supporting the vanes. For the highest stable swirl angle setting a nacelle area based drag coefficient of 0.8 was achieved with a full-scale Overall Sound Pressure Level (OASPL) of about 40dBA at the ICAO approach certification point.

  3. MEMS Based Acoustic Array

    Science.gov (United States)

    Sheplak, Mark (Inventor); Nishida, Toshikaza (Inventor); Humphreys, William M. (Inventor); Arnold, David P. (Inventor)

    2006-01-01

    Embodiments of the present invention described and shown in the specification aid drawings include a combination responsive to an acoustic wave that can be utilized as a dynamic pressure sensor. In one embodiment of the present invention, the combination has a substrate having a first surface and an opposite second surface, a microphone positioned on the first surface of the substrate and having an input and a first output and a second output, wherein the input receives a biased voltage, and the microphone generates an output signal responsive to the acoustic wave between the first output and the second output. The combination further has an amplifier positioned on the first surface of the substrate and having a first input and a second input and an output, wherein the first input of the amplifier is electrically coupled to the first output of the microphone and the second input of the amplifier is electrically coupled to the second output of the microphone for receiving the output sinual from the microphone. The amplifier is spaced from the microphone with a separation smaller than 0.5 mm.

  4. Acoustics and Hearing

    CERN Document Server

    Damaske, Peter

    2008-01-01

    When one listens to music at home, one would like to have an acoustic impression close to that of being in the concert hall. Until recently this meant elaborate multi-channelled sound systems with 5 or more speakers. But head-related stereophony achieves the surround-sound effect in living rooms with only two loudspeakers. By virtue of their slight directivity as well as an electronic filter the limitations previously common to two-speaker systems can be overcome and this holds for any arbitrary two-channel recording. The book also investigates the question of how a wide and diffuse sound image can arise in concert halls and shows that the quality of concert halls decisively depends on diffuse sound images arising in the onset of reverberation. For this purpose a strong onset of reverberation is modified in an anechoic chamber by electroacoustic means. Acoustics and Hearing proposes ideas concerning signal processing in the auditory system that explain the measured results and the resultant sound effects plea...

  5. Acoustic data transmission method

    Energy Technology Data Exchange (ETDEWEB)

    Duckworth, A.

    1991-09-17

    This patent describes a method for transmitting time line data through a drillstring having drill pipe sections connected end-to-end by joints from a first location below the surface of the earth to a second location at or near the surface of the earth, the length and cross-sectional area of the drill pipe sections being different from the length and cross-sectional area of the joints. It comprises generating acoustic data signals having a single frequency content in at least one passband of the drillstring; transmitting the data signals through the drillstring from either the first location to the second location or from the second location to the first location during a time period prior to the onset of reflective interference caused by the data signals reflecting from along the length of the drillstring, the time period being equal to or less than the time for the data signals to travel three lengths of the drillstring; stopping the transmission of data signals at the onset of the reflective interference and allowing the acoustic signals to substantially attenuate; and detecting the data signals at the respective first or second location.

  6. The MERLIN programme: Pt. 5

    International Nuclear Information System (INIS)

    The MERLIN rig is intended to investigate the deformation behaviour of Zircaloy fuel rod cladding under conditions approximating those of a large break loss of coolant accident (LOCA). An assembly of electrically heated fuel rod simulators (6X6 cluster) is subjected to a temperature transient simulating that predicted to occur in a LOCA, including the initiation of bottom reflooding at a suitable stage. The Bundle B Thermal-Hydraulic test series was intended to commission the test facility and to obtain the operating conditions which would produce a suitable temperature transient for the investigation of clad ballooning at high coolant sub-channel blockages. In addition, the vibration produced by reflooding was to be measured during the course of the programme. The early stages of the programme (ramp test and low power reflooding tests) were successfully accomplished, although a major part of the test section instrumentation was found to be unreliable. A limited number of low power tests designed to investigate starting conditions was followed by an accelerated programme to derive a high temperature burst test transient, with the limited aim of allowing good rig commissioning data to be obtained. A successful burst test was carried out as the final experiment of the programme. (author)

  7. Carioca hospitality programme: Rio 2016

    OpenAIRE

    2016-01-01

    The "Hospitality programme" at the Rio 2016 Games venues was designed to attend the specific needs of partners and their clients in a transparent and flexible manner. In this guide, you will find information and standards that will help in your choice, and in the planning of this incredible experience.

  8. Summer Student Programme – Report

    CERN Document Server

    Bellora, Andrea

    2016-01-01

    This is the report on the studies about radiation damage on silicon strips detectors I've performed during my Summer Student Programme. A parameter to describe the damage amount has been defined, as well as his behaviour over time and absorbed dose.

  9. Portugal's Secondary School Modernisation Programme

    Science.gov (United States)

    Heitor, Teresa V.; Freire da Silva, Jose M. R.

    2009-01-01

    The aim of the Secondary School Modernisation Programme, being implemented in Portugal by "Parque Escolar, EPE", is based on the pursuit of quality and makes Portuguese education a potential international benchmark. This paper discusses the strategies adopted to reorganise school spaces. It describes the conceptual model and highlights the…

  10. Nondestructive Evaluation of Metal Fatigue Using Nonlinear Acoustics

    Science.gov (United States)

    Cantrell, John H., Jr.

    2008-01-01

    Safe-life and damage-tolerant design philosophies of high performance structures have driven the development of various methods to evaluate nondestructively the accumulation of damage in such structures resulting from cyclic loading. Although many techniques have proven useful, none has been able to provide an unambiguous, quantitative assessment of damage accumulation at each stage of fatigue from the virgin state to fracture. A method based on nonlinear acoustics is shown to provide such a means to assess the state of metal fatigue. The salient features of an analytical model are presented of the microelastic-plastic nonlinearities resulting from the interaction of an acoustic wave with fatigue-generated dislocation substructures and cracks that predictably evolve during the metal fatigue process. The interaction is quantified by the material (acoustic) nonlinearity parameter extracted from acoustic harmonic generation measurements. The parameters typically increase monotonically by several hundred percent over the fatigue life of the metal, thus providing a unique measure of the state of fatigue. Application of the model to aluminum alloy 2024-T4, 410Cb stainless steel, and IN100 nickel-base superalloy specimens fatigued using different loading conditions yields good agreement between theory and experiment. Application of the model and measurement technique to the on-site inspection of steam turbine blades is discussed.

  11. Programmable shape transformation of elastic spherical domes.

    Science.gov (United States)

    Abdullah, Arif M; Braun, Paul V; Hsia, K Jimmy

    2016-07-20

    We investigate mismatch strain driven programmable shape transformation of spherical domes and report the effects of different geometric and structural characteristics on dome behavior in response to applied mismatch strain. We envision a bilayer dome design where the differential swelling of the inner layer with respect to the passive outer layer in response to changes in dome surroundings (such as the introduction of an organic solvent) introduces mismatch strain within the bilayer system and causes dome shape transformation. Finite element analysis reveals that, in addition to snap-through, spherical domes undergo bifurcation buckling and eventually gradual bending to morph into cylinders with increasing mismatch strain. Besides demonstrating how the snap-through energy barrier depends on the spherical dome shape, our analysis identifies three distinct groups of dome geometries based on their mismatch strain-transformed configuration relationships. Our experiments with polymer-based elastic bilayer domes that exhibit differential swelling in organic solvents qualitatively confirm the finite element predictions. We establish that, in addition to externally applied stimuli (mismatch strain), bilayer spherical dome morphing can be tuned and hence programmed through its geometry and structural characteristics. Incorporation of an elastic instability mechanism such as snap-through within the framework of stimuli-responsive functional devices can improve their response time which is otherwise controlled by diffusion. Hence, our proposed design guidelines can be used to realize deployable, multi-functional, reconfigurable, and therefore, adaptive structures responsive to a diverse set of stimuli across multiple length scales.

  12. Robotically Driven Architectural Production

    OpenAIRE

    Bier, H.H.

    2014-01-01

    Robotically driven architectural production advances seamless, computer-numerically controlled (CNC) and robotically supported design to production and operation processes enabling im-plementation of robotically driven buildings from conceptualisation to use. It enables production of free-formed, heterogeneous, optimized structures in order to address specific requirements in terms of properties (density, consistency, rigidity, etc.) and behaviours (re-configurability, responsiveness, etc.) i...

  13. Acoustic cavitation and sonochemistry

    OpenAIRE

    Stricker, L.

    2013-01-01

    Sonochemistry is the use of cavitation for achieving a chemical conversion. When microbubbles are driven in the nonlinear regime, localized extreme temperatures (up to 10000 K) and pressures (up to 1000 bar) can be reached upon collapse, the surrounding liquid remaining ambient,thus giving origin to intriguing phenomena, such as light emission (sonoluminescence) and high temperature chemical reactions (sonochemistry). These reaction products then diffuse outside the bubble and dissolve inside...

  14. The International Comparison Programme: 2005 results and supporting the programme

    OpenAIRE

    Ben Whitestone

    2008-01-01

    Explores improvements made in the latest round of the ICP initiative and UK Government support for it in AfricaThe results of the International Comparison Programme (ICP) were released by the World Bank in December 2007. The ICP is a global initiative to collect comparative price data and estimate relative price levels between countries. These figures allow international comparisons of real economic wealth to be made, and hence provide an essential tool for governments designing aid, trade an...

  15. Impact evaluation of child nutrition programmes

    NARCIS (Netherlands)

    Hoorweg, J.C.

    1988-01-01

    Review of current practices and recent developments in impact evaluation of nutrition programmes for preschool children in developing countries. A survey of the major types of nutrition programmes for young children - nutrition education, food supplementation, and nutrition rehabilitation - is follo

  16. Planning and implementation of nuclear research programmes

    International Nuclear Information System (INIS)

    The planning and implementation of nuclear research programmes in developed and developing countries is discussed. The main aspects of these programmes in USA, France, Japan, India and Brazil are reported. (M.W.O.)

  17. Acoustic Signal Feature Extraction of Vehicle Targets

    Institute of Scientific and Technical Information of China (English)

    蓝金辉; 马宝华; 李科杰

    2002-01-01

    Acoustic signal feature extraction is an important part of target recognition. The mechanisms for producing acoustic signals and their propagation are analyzed to extract the features of the radiated noise from different targets. Analysis of the acoustic spectra of typical vehicle targets acquired outdoors shows that the vehicles can be classified based on the acoustic spectra and amplitudes.

  18. The JOSHUA (J80) system programmer`s manual

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, A.O.; McCort, J.T.; Westmoreland, B.W.

    1993-08-01

    The JOSHUA system routines (JS routines) can be used to manage a JOSHUA data base and execute JOSHUA modules on VAX/VMS and IBM/MVS computer systems. This manual provides instructions for using the JS routines and information about the internal data structures and logic used by the routines. It is intended for use primarily by JOSHUA systems programmers, however, advanced applications programmers may also find it useful. The JS routines are, as far as possible, written in ANSI FORTRAN 77 so that they are easily maintainable and easily portable to different computer systems. Nevertheless, the JOSHUA system provides features that are not available in ANSI FORTRAN 77, notably dynamic module execution and a data base of named, variable length, unformatted records, so some parts of the routines are coded in nonstandard FORTRAN or assembler (as a last resort). In most cases, the nonstandard sections of code are different for each computer system. To make it easy for programmers using the JS routines to avoid naming conflicts, the JS routines and common block all have six character names that begin with the characters {open_quotes}JS.{close_quotes} Before using this manual, one should be familiar with the JOSHUA system as described in {open_quotes}The JOSHUA Users` Manual,{close_quotes} ANSI FORTRAN 77, and at least one of the computer systems for which the JS routines have been implemented.

  19. Acoustic cavitation movies

    Science.gov (United States)

    Crum, Lawrence A.

    2003-04-01

    Acoustic cavitation is a phenomenon that occurs on microsecond time scales and micron length scales, yet, it has many macroscopic manifestations. Accordingly, it is often difficult, at least for the author, to form realistic physical descriptions of the specific mechanisms through which it expresses itself in our macroscopic world. For example, there are still many who believe that cavitation erosion is due to the shock wave that is emitted by bubble implosion, rather than the liquid jet created on asymmetric collapse...and they may be right. Over the years, the author has accumulated a number of movies and high-speed photographs of cavitation activity, which he uses to form his own visual references. In the time allotted, he will show a number of these movies and photographs and discuss their relevance to existing technological problems. A limited number of CDs containing the presented materials will be available to interested individuals. [Work supported in part by the NIH, USAMRMC, and the ONR.

  20. Acoustic emission testing

    CERN Document Server

    Grosse, Christian U

    2008-01-01

    Acoustic Emission (AE) techniques have been studied in civil engineering for a long time. The techniques are recently going to be more and more applied to practical applications and to be standardized in the codes. This is because the increase of aging structures and disastrous damages due to recent earthquakes urgently demand for maintenance and retrofit of civil structures in service for example. It results in the need for the development of advanced and effective inspection techniques. Thus, AE techniques draw a great attention to diagnostic applications and in material testing. The book covers all levels from the description of AE basics for AE beginners (level of a student) to sophisticated AE algorithms and applications to real large-scale structures as well as the observation of the cracking process in laboratory specimen to study fracture processes.

  1. Acoustic frequency combs for carrier-envelope phase stabilization.

    Science.gov (United States)

    Borchers, Bastian; Lücking, Fabian; Steinmeyer, Günter

    2014-02-01

    A method for improved performance of feed-forward carrier-envelope phase stabilization in amplified laser sources is presented and experimentally demonstrated. The phase stabilization scheme is applicable for a broad range of repetition rates spanning from subhertz to 100 kHz. The method relies on driving an acousto-optic frequency shifter by few-cycle transients. The phase of these transients suitably controls the grating phase of the generated index grating inside the shifter material. This approach removes beam pointing as well as amplitude noise issues observed in continuously driven feed-forward schemes. The synthesis of these gratings can be understood as the acoustic equivalent of mode-locking or acoustic frequency combs. PMID:24487861

  2. Rotational manipulation of single cells and organisms using acoustic waves

    Science.gov (United States)

    Ahmed, Daniel; Ozcelik, Adem; Bojanala, Nagagireesh; Nama, Nitesh; Upadhyay, Awani; Chen, Yuchao; Hanna-Rose, Wendy; Huang, Tony Jun

    2016-01-01

    The precise rotational manipulation of single cells or organisms is invaluable to many applications in biology, chemistry, physics and medicine. In this article, we describe an acoustic-based, on-chip manipulation method that can rotate single microparticles, cells and organisms. To achieve this, we trapped microbubbles within predefined sidewall microcavities inside a microchannel. In an acoustic field, trapped microbubbles were driven into oscillatory motion generating steady microvortices which were utilized to precisely rotate colloids, cells and entire organisms (that is, C. elegans). We have tested the capabilities of our method by analysing reproductive system pathologies and nervous system morphology in C. elegans. Using our device, we revealed the underlying abnormal cell fusion causing defective vulval morphology in mutant worms. Our acoustofluidic rotational manipulation (ARM) technique is an easy-to-use, compact, and biocompatible method, permitting rotation regardless of optical, magnetic or electrical properties of the sample under investigation. PMID:27004764

  3. Naturally enhanced ion-acoustic spectra and their interpretation

    DEFF Research Database (Denmark)

    Sedgemore-Schulthess, K.J.F.; St. Maurice, J.P.

    2001-01-01

    Incoherent scatter radars are designed to detect scatter from thermal fluctuations in the ionosphere. These fluctuations contain, among other things, features associated with ion-acoustic waves driven by random motions within the plasma. The resulting spectra are generally broad and noisy, but...... nevertheless the technique can, through a detailed analysis of spectra, be used to measure a range of physical parameters in the Earth's upper atmosphere, and provides a powerful diagnostic in studies of magnetosphere-ionosphere coupling, thermosphere dynamics and the geospace environment in general. In recent...... acceleration, wave-particle and wave-wave interactions in the ionosphere, and their association with magnetospheric processes. There is now a substantial body of literature documenting observations of enhanced ion-acoustic spectra, but there remains controversy over generation mechanisms. We present a review...

  4. A theory evaluation of an induction programme

    Directory of Open Access Journals (Sweden)

    Kenrick Hendricks

    2012-07-01

    Full Text Available Orientation: An induction programme is commonly used to help new employees understand their job within the organisation. Research purpose: The main aim of this study was to examine whether or not the programme theory of an induction programme was plausible and would lead to the intended outcomes as described by the programme manager.Motivation for the study: Induction training is one of the most common training programmes in an organisation. However, there is little research to evaluate whether or not the activities of an induction programme will lead to the intended outcomes of such a programme.Research design, approach and method: This theory evaluation used a descriptive design. One hundred and thirteen employees of a media company completed a ten-item, five-point Likert scale which measured their perceptions of the programme’s outcome, identification with the organisation and intentions to stay with the organisation.Main findings: From this theory evaluation it was apparent that an induction programme based on an implausible programme theory could be problematic. An implausible programme theory affects the design of the programme activities and unsuitable activities may not deliver the desired outcomes.Practical/managerial implications: The intention of the evaluation is to guide human resource managers through a process of replacing an implausible programme theory with one that is plausible, and which ensures better alignment of programme activities and outcomes.Contribution/value-add: The evaluators showed how a plausible programme theory could improve programme design. This redesigned induction programme may lead to benefits, such as staff retention and company identification, rather than the vague assumption that it has been conforming to a legal obligation.

  5. Rural Energy Development Programme-Nepal

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    On 16 Auguest 1996 the Rural Energy Develoment Programme (REDP) was initiated with the aim of improving livelihoods of rural people and pressrving the environment through the promotion of rural energy systems. The Programme is run by the United Nations Deelopment Programme and His Majesty's Government of Nepal.

  6. School Security Assessment Programme in Australia

    Science.gov (United States)

    Marrapodi, John

    2007-01-01

    This article describes a successful security risk management programme in Australia. The state-wide programme follows a structured risk management approach focusing on the safety and security of people, information, provision, and assets in the school environment. To assist school principals, a Security Risk Assessment Programme was developed on a…

  7. Real-time motion control and data acquisition system for scanning X-ray microscopy using programmable hardware

    International Nuclear Information System (INIS)

    We developed a real-time motion control and measurement system for a scanning transmission X-ray microscope. The system was designed with an FPGA (field-programmable gate array), which is a programmable, reconfigurable circuit for real-time feature modification. This system enabled specimen stage control driven by a piezoelectric element and precise stage position measurement with a laser interferometer. Programmable hardware processing with FPGA realized high-speed control and measurement that cannot be handled by software processing. This system enables very high-speed control and measurement such as 'on the fly' measurement.

  8. JavaScript programmer's reference

    CERN Document Server

    Valentine, Thomas

    2013-01-01

    JavaScript Programmer's Reference is an invaluable resource that won't stray far from your desktop (or your tablet!). It contains detailed information on every JavaScript object and command, and combines that reference with practical examples showcasing how you can use those commands in the real world. Whether you're just checking the syntax of a method or you're starting out on the road to JavaScript mastery, the JavaScript Programmer's Reference will be an essential aid.  With a detailed and informative tutorial section giving you the ins and outs of programming with JavaScript and the DOM f

  9. Effects of subsampling of passive acoustic recordings on acoustic metrics.

    Science.gov (United States)

    Thomisch, Karolin; Boebel, Olaf; Zitterbart, Daniel P; Samaran, Flore; Van Parijs, Sofie; Van Opzeeland, Ilse

    2015-07-01

    Passive acoustic monitoring is an important tool in marine mammal studies. However, logistics and finances frequently constrain the number and servicing schedules of acoustic recorders, requiring a trade-off between deployment periods and sampling continuity, i.e., the implementation of a subsampling scheme. Optimizing such schemes to each project's specific research questions is desirable. This study investigates the impact of subsampling on the accuracy of two common metrics, acoustic presence and call rate, for different vocalization patterns (regimes) of baleen whales: (1) variable vocal activity, (2) vocalizations organized in song bouts, and (3) vocal activity with diel patterns. To this end, above metrics are compared for continuous and subsampled data subject to different sampling strategies, covering duty cycles between 50% and 2%. The results show that a reduction of the duty cycle impacts negatively on the accuracy of both acoustic presence and call rate estimates. For a given duty cycle, frequent short listening periods improve accuracy of daily acoustic presence estimates over few long listening periods. Overall, subsampling effects are most pronounced for low and/or temporally clustered vocal activity. These findings illustrate the importance of informed decisions when applying subsampling strategies to passive acoustic recordings or analyses for a given target species. PMID:26233026

  10. The assessment of borehole cement sealing characteristics by acoustic waveform analysis

    International Nuclear Information System (INIS)

    Acoustic waveform analysis has been used to provide a quantitative analysis of the effectiveness of cement grouting for sealing three adjacent boreholes drilled at Harwell, Oxon, as part of a research programme into the disposal of radioactive wastes into argillaceous formations. Results indicate that bonding at cement/casing and cement/formation interfaces would be inadequate for sealing a radioactive waste repository and the use of a backfilling material such as bentonite is advocated. (U.K.)

  11. Hybrid optical and acoustic force based sorting

    Science.gov (United States)

    O'Mahoney, Paul; Brodie, Graham W.; Wang, Han; Demore, Christine E. M.; Cochran, Sandy; Spalding, Gabriel C.; MacDonald, Michael P.

    2014-09-01

    We report the combined use of optical sorting and acoustic levitation to give particle sorting. Differing sizes of microparticles are sorted optically both with and without the aid of acoustic levitation, and the results compared to show that the use of acoustic trapping can increase sorting efficiency. The use of a transparent ultrasonic transducer is also shown to streamline the integration of optics and acoustics. We also demonstrate the balance of optical radiation pressure and acoustic levitation to achieve vertical sorting.

  12. Programmable Grit-Blasting System

    Science.gov (United States)

    Burley, Richard K.

    1988-01-01

    In programmable grit-blasting system undergoing design, controller moves blasting head to precise positions to shape or remove welding defects from parts. Controller holds head in position for preset dwell time and moves head to new position along predetermined path. Position of articulated head established by pair of servomotors according to programmed signals from controller. Head similar to video borescope. Used to remove welding defects in blind holes. Suited for repetitive production operations in grit-blast box.

  13. LEP Celebration : the official programme

    CERN Document Server

    CERN. Geneva

    2000-01-01

    At 14:00: Groupe de Jazz "Wolfgang & The Werewolves" . The official programme begins at 15:00 with an introduction from the Director General, and Professor Martinus Veltman will give the keynote speech. Heads of national delegations represented at ministerial level will then make their speeches, following which a commemorative plaque will be unveiled. A specially commissioned ballet by Maurice Béjart will bring the ceremony to a close.

  14. Fast reactor programme in India

    Indian Academy of Sciences (India)

    P Chellapandi; P R Vasudeva Rao; Prabhat Kumar

    2015-09-01

    Role of fast breeder reactor (FBR) in the Indian context has been discussed with appropriate justification. The FBR programme since 1985 till 2030 is highlighted focussing on the current status and future direction of fast breeder test reactor (FBTR), prototype fast breeder reactor (PFBR) and FBR-1 and 2. Design and technological challenges of PFBR and design and safety targets with means to achieve the same are the major highlights of this paper.

  15. Guam Fish Aggregating Device programme

    OpenAIRE

    Torres, A.

    2000-01-01

    Installation and maintenance of FADs by the Government of Guam began in 1979, initially with funding from the Salstonstall-Kennedy Act through the Pacific Tuna Development Foundation. Current funding for the Guam FAD project is provided through the Dingell-Johnson/Wallop-Breaux Sport Fish Restoration programme, a Federal Aid Project funded by taxes collected on the purchase of fishing equipment and motorboat fuels nationwide. There are now sixteen operational FAD sites in Guam's waters. At a ...

  16. The MERLIN programme: Pt. 9

    International Nuclear Information System (INIS)

    The MERLIN rig is intended to investigate the deformation behaviour of Zircaloy fuel rod cladding under conditions approximating those of a large break LOCA. A preliminary series of experiments (the MERLIN Bundle B programme) has been carried out, with the aim of characterising the rig. This series of experiments concluded with a burst test, during which the cladding of a number of fuel rod simulators distended and burst. This Report describes the post test examination of the Bundle. (author)

  17. Model Driven Engineering

    Science.gov (United States)

    Gaševic, Dragan; Djuric, Dragan; Devedžic, Vladan

    A relevant initiative from the software engineering community called Model Driven Engineering (MDE) is being developed in parallel with the Semantic Web (Mellor et al. 2003a). The MDE approach to software development suggests that one should first develop a model of the system under study, which is then transformed into the real thing (i.e., an executable software entity). The most important research initiative in this area is the Model Driven Architecture (MDA), which is Model Driven Architecture being developed under the umbrella of the Object Management Group (OMG). This chapter describes the basic concepts of this software engineering effort.

  18. Data-Driven Method for High Level Rendering Pipeline Construction

    OpenAIRE

    Krasnoproshin, V. V.; Mazouka, D.

    2014-01-01

    The paper describes a software methodology for the graphics pipeline extension. It is argued that common modern visualization techniques do not satisfy current visualization software development requirements adequately enough. The proposed approach is based on specialized formal language called visualization algebra. By invoking data-driven design principles inherited from the existing programmable pipeline technology, the technique has a potential to reduce visualization software development...

  19. Inertial confinement fusion driven by heavy-ion beams

    International Nuclear Information System (INIS)

    Fundamental concepts, current status and future prospects of heavy-ion-driven inertial confinement fusion are described. Target physics issues are emphasised. An account is given of experimental programmes now under way, including beam/plasma interaction and accelerator physics experiments. Plans for high-intensity beam/target research using heavy-ion beams from the synchrotron at GSI, Darmstadt, FRG are presented. (author)

  20. Instant RSpec test driven development how-to

    CERN Document Server

    Feduke, Charles

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. A concise guide that delivers immediate results with practical recipes on learning practical hints.This book is aimed at Ruby developers with beginner level expertise who want to use RSpec and test driven development methodology to improve the code they write. Experienced programmers new to Ruby will also benefit from this book which also covers creating testable, idiomatic Ruby code

  1. Frequency Steered Acoustic Transducer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase II project is to fabricate, characterize, and verify performance of a new type of frequency steered acoustic...

  2. Frequency Steered Acoustic Transducer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project is to develop, fabricate, and characterize a novel frequency steered acoustic transducer (FSAT) for the...

  3. Reverberant Acoustic Test Facility (RATF)

    Data.gov (United States)

    Federal Laboratory Consortium — The very large Reverberant Acoustic Test Facility (RATF) at the NASA Glenn Research Center (GRC), Plum Brook Station, is currently under construction and is due to...

  4. Cryogenic Acoustic Suppression Testing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed project will explore and test the feasibility and effectiveness of using a cryogenic fluid (liquid nitrogen) to facilitate acoustic suppression in a...

  5. NEAR-FIELD ACOUSTIC HOLOGRAPHY FOR SEMI-FREE ACOUSTIC FIELD BASED ON WAVE SUPERPOSITION APPROACH

    Institute of Scientific and Technical Information of China (English)

    LI Weibing; CHEN Jian; YU Fei; CHEN Xinzhao

    2006-01-01

    In the semi-free acoustic field, the actual acoustic pressure at any point is composed of two parts: The direct acoustic pressure and the reflected acoustic pressure. The general acoustic holographic theories and algorithms request that there is only the direct acoustic pressure contained in the pressure at any point on the hologram surface, consequently, they cannot be used to reconstruct acoustic source and predict acoustic field directly. To take the reflected pressure into consideration, near-field acoustic holography for semi-free acoustic field based on wave superposition approach is proposed to realize the holographic reconstruction and prediction of the semi-free acoustic field, and the wave superposition approach is adopted as a holographic transform algorithm. The proposed theory and algorithm are realized and verified with a numerical example,and the drawbacks of the general theories and algorithms in the holographic reconstruction and prediction of the semi-free acoustic field are also demonstrated by this numerical example.

  6. Acoustic Rectification in Dispersive Media

    Science.gov (United States)

    Cantrell, John H.

    2008-01-01

    It is shown that the shapes of acoustic radiation-induced static strain and displacement pulses (rectified acoustic pulses) are defined locally by the energy density of the generating waveform. Dispersive properties are introduced analytically by assuming that the rectified pulses are functionally dependent on a phase factor that includes both dispersive and nonlinear terms. The dispersion causes an evolutionary change in the shape of the energy density profile that leads to the generation of solitons experimentally observed in fused silica.

  7. Simplified Rotation In Acoustic Levitation

    Science.gov (United States)

    Barmatz, M. B.; Gaspar, M. S.; Trinh, E. H.

    1989-01-01

    New technique based on old discovery used to control orientation of object levitated acoustically in axisymmetric chamber. Method does not require expensive equipment like additional acoustic drivers of precisely adjustable amplitude, phase, and frequency. Reflecting object acts as second source of sound. If reflecting object large enough, close enough to levitated object, or focuses reflected sound sufficiently, Rayleigh torque exerted on levitated object by reflected sound controls orientation of object.

  8. Stable And Oscillating Acoustic Levitation

    Science.gov (United States)

    Barmatz, Martin B.; Garrett, Steven L.

    1988-01-01

    Sample stability or instability determined by levitating frequency. Degree of oscillation of acoustically levitated object along axis of levitation chamber controlled by varying frequency of acoustic driver for axis above or below frequency of corresponding chamber resonance. Stabilization/oscillation technique applied in normal Earth gravity, or in absence of gravity to bring object quickly to rest at nominal levitation position or make object oscillate in desired range about that position.

  9. Study Acoustic Emissions from Composites

    Science.gov (United States)

    Walker, James; Workman,Gary

    1998-01-01

    The purpose of this work will be to develop techniques for monitoring the acoustic emissions from carbon epoxy composite structures at cryogenic temperatures. Performance of transducers at temperatures ranging from ambient to cryogenic and the characteristics of acoustic emission from composite structures will be studied and documented. This entire effort is directed towards characterization of structures used in NASA propulsion programs such as the X-33.

  10. Acoustic agglomeration of fine particles based on a high intensity acoustical resonator

    Science.gov (United States)

    Zhao, Yun; Zeng, Xinwu; Tian, Zhangfu

    2015-10-01

    Acoustic agglomeration (AA) is considered to be a promising method for reducing the air pollution caused by fine aerosol particles. Removal efficiency and energy consuming are primary parameters and generally have a conflict with each other for the industry applications. It was proved that removal efficiency is increased with sound intensity and optimal frequency is presented for certain polydisperse aerosol. As a result, a high efficiency and low energy cost removal system was constructed using acoustical resonance. High intensity standing wave is generated by a tube system with abrupt section driven by four loudspeakers. Numerical model of the tube system was built base on the finite element method, and the resonance condition and SPL increase were confirmd. Extensive tests were carried out to investigate the acoustic field in the agglomeration chamber. Removal efficiency of fine particles was tested by the comparison of filter paper mass and particle size distribution at different operating conditions including sound pressure level (SPL), and frequency. The experimental study has demonstrated that agglomeration increases with sound pressure level. Sound pressure level in the agglomeration chamber is between 145 dB and 165 dB from 500 Hz to 2 kHz. The resonance frequency can be predicted with the quarter tube theory. Sound pressure level gain of more than 10 dB is gained at resonance frequency. With the help of high intensity sound waves, fine particles are reduced greatly, and the AA effect is enhanced at high SPL condition. The optimal frequency is 1.1kHz for aerosol generated by coal ash. In the resonace tube, higher resonance frequencies are not the integral multiplies of the first one. As a result, Strong nonlinearity is avoided by the dissonant characteristic and shock wave is not found in the testing results. The mechanism and testing system can be used effectively in industrial processes in the future.

  11. Opto-acoustic cell permeation

    Energy Technology Data Exchange (ETDEWEB)

    Visuri, S R; Heredia, N

    2000-03-09

    Optically generated acoustic waves have been used to temporarily permeate biological cells. This technique may be useful for enhancing transfection of DNA into cells or enhancing the absorption of locally delivered drugs. A diode-pumped frequency-doubled Nd:YAG laser operating at kHz repetition rates was used to produce a series of acoustic pulses. An acoustic wave was formed via thermoelastic expansion by depositing laser radiation into an absorbing dye. Generated pressures were measured with a PVDF hydrophone. The acoustic waves were transmitted to cultured and plated cells. The cell media contained a selection of normally- impermeable fluorescent-labeled dextran dyes. Following treatment with the opto-acoustic technique, cellular incorporation of dyes, up to 40,000 Molecular Weight, was noted. Control cells that did not receive opto-acoustic treatment had unremarkable dye incorporation. Uptake of dye was quantified via fluorescent microscopic analysis. Trypan Blue membrane exclusion assays and fluorescent labeling assays confirmed the vitality of cells following treatment. This method of enhanced drug delivery has the potential to dramatically reduce required drug dosages and associated side effects and enable revolutionary therapies.

  12. Swiss Biomass Programme - Overview report on the 2007 research programme; Programm Biomasse: Ueberblicksbericht zum Forschungsprogramm 2007

    Energy Technology Data Exchange (ETDEWEB)

    Binggeli, D.; Guggisberg, B.

    2008-07-01

    This illustrated report for the Swiss Federal Office of Energy (SFOE) presents an overview of the results obtained in 2007 within the framework of the Swiss Biomass research programme. The potential for biomass use in Switzerland is reviewed and the emphases of the national programme are discussed. The results obtained are noted for the following areas: process optimisation, including - amongst others - particle emissions and control aspects as well as combined wood-pellets and solar heating systems. Projects involving non-wood biomass are reported on, including biomass digesters and various biogas systems. Further reports deal with the analysis and optimisation of material flows, organic pollutants and methane losses. New conversion technologies are reported on. Further reports deal with basic strategies and concepts in the area of biomass usage. National and international co-operation is also discussed. A selection of innovative pilot and demonstration projects is also presented and research and development projects are listed.

  13. Prediction of acoustic comfort and acoustic silence in Goan Catholic churches

    OpenAIRE

    Menino A. S. M. P. Tavares; S. Rajagopalan; Satish J. Sharma; António P. O. Carvalho

    2009-01-01

    Acoustic Comfort and Acoustic Silence are determinants of tranquility in a worship space. The results presented here are part of a study that investigates the behaviour of acoustically constituted worship parameters in six Catholic churches (Goa, India). Acoustic comfort is quantified through an Acoustic Comfort Impression Index which measures the net comfort induced through the optimization of the desired subjective acoustic impressions for different types of music and different music source...

  14. Discovery Driven Growth

    DEFF Research Database (Denmark)

    Bukh, Per Nikolaj

    2009-01-01

    Anmeldelse af Discovery Driven Growh : A breakthrough process to reduce risk and seize opportunity, af Rita G. McGrath & Ian C. MacMillan, Boston: Harvard Business Press. Udgivelsesdato: 14 august......Anmeldelse af Discovery Driven Growh : A breakthrough process to reduce risk and seize opportunity, af Rita G. McGrath & Ian C. MacMillan, Boston: Harvard Business Press. Udgivelsesdato: 14 august...

  15. Enlargement of the External Mobility Programme

    CERN Multimedia

    HR Department

    2008-01-01

    The External Mobility Programme was launched at the end of September 2007. Initially, the programme was aimed at staff members on limited-duration contracts, having received formal notification of the termination of their employment contract at CERN, to help them towards their next employment. The programme provides a privileged, fast-track entry into the recruitment process of partner companies. Despite the short time since its inception, the programme has already delivered some encouraging and concrete results in terms of interviews granted to participating staff. The Programme has raised considerable interest from both CERN personnel as well as from several major European companies. CERN Management has decided to broaden the scope of the External Mobility Programme. The Programme is now open to: All staff members whose limited duration contract will end in less than one year, as well as all those with indefinite contracts. All fellows who have been employed by CERN fo...

  16. Enlargement of the External Mobility Programme

    CERN Multimedia

    HR Department

    2008-01-01

    The External Mobility Programme was launched at the end of September 2007. Initially, the programme was aimed at staff members on limited-duration contracts having received formal notification of the termination of their employment contract at CERN, to help them towards their next employment. The programme provides a privileged, fast-track entry into the recruitment process of partner companies. Despite the short time since its inception, the programme has already delivered some encouraging and concrete results in terms of interviews granted to participating staff. The Programme has attracted considerable interest from both CERN personnel as well as from several major European companies. The CERN Management has decided to broaden the scope of the External Mobility Programme. The Programme is now open to: All staff members whose limited duration contract will end in less than one year, as well as all those with indefinite contracts. All fellows who have been employed by CE...

  17. Programmable hardware for reconfigurable computing systems

    Science.gov (United States)

    Smith, Stephen

    1996-10-01

    In 1945 the work of J. von Neumann and H. Goldstein created the principal architecture for electronic computation that has now lasted fifty years. Nevertheless alternative architectures have been created that have computational capability, for special tasks, far beyond that feasible with von Neumann machines. The emergence of high capacity programmable logic devices has made the realization of these architectures practical. The original ENIAC and EDVAC machines were conceived to solve special mathematical problems that were far from today's concept of 'killer applications.' In a similar vein programmable hardware computation is being used today to solve unique mathematical problems. Our programmable hardware activity is focused on the research and development of novel computational systems based upon the reconfigurability of our programmable logic devices. We explore our programmable logic architectures and their implications for programmable hardware. One programmable hardware board implementation is detailed.

  18. Acoustic Signal Processing

    Science.gov (United States)

    Hartmann, William M.; Candy, James V.

    Signal processing refers to the acquisition, storage, display, and generation of signals - also to the extraction of information from signals and the re-encoding of information. As such, signal processing in some form is an essential element in the practice of all aspects of acoustics. Signal processing algorithms enable acousticians to separate signals from noise, to perform automatic speech recognition, or to compress information for more efficient storage or transmission. Signal processing concepts are the building blocks used to construct models of speech and hearing. Now, in the 21st century, all signal processing is effectively digital signal processing. Widespread access to high-speed processing, massive memory, and inexpensive software make signal processing procedures of enormous sophistication and power available to anyone who wants to use them. Because advanced signal processing is now accessible to everybody, there is a need for primers that introduce basic mathematical concepts that underlie the digital algorithms. The present handbook chapter is intended to serve such a purpose.

  19. Acoustics of the Intonarumori

    Science.gov (United States)

    Serafin, Stefania

    2005-04-01

    The Intonarumori were a family of musical instruments invented by the Italian futurist composer and painter Luigi Russolo. Each Intonarumori was made of a wooden parallelepiped sound box, inside which a wheel of different sizes and materials was setting into vibration a catgut or metal string. The pitch of the string was varied by using a lever, while the speed of the wheel was controlled by the performer using a crank. At one end of the string there was a drumhead that transmitted vibrations to the speaker. Unfortunately, all the original Intonarumori were destroyed after a fire during World War II. Since then, researchers have tried to understand the sound production mechanism of such instruments, especially by consulting the patents compiled by Russolo or by reading his book ``The art of noise.'' In this paper we describe the acoustics of the Intonarumori. Based on such description, we propose physical models that simulate such instruments. The intonarumori's string is modeled using a one dimensional waveguide, which is excited either by an impact or a friction model. The body of the instrument is modeled using a 3-D rectangular mesh, while the horn is considered as an omnidirectional radiator.

  20. Y-shaped jets driven by an ultrasonic beam reflecting on a wall.

    Science.gov (United States)

    Moudjed, Brahim; Botton, Valéry; Henry, Daniel; Millet, Séverine; Ben Hadid, Hamda

    2016-05-01

    This paper presents an original experimental and numerical investigation of acoustic streaming driven by an acoustic beam reflecting on a wall. The water experiment features a 2 MHz acoustic beam totally reflecting on one of the tank glass walls. The velocity field in the plane containing the incident and reflected beam axes is investigated using Particle Image Velocimetry (PIV). It exhibits an original y-shaped structure: the impinging jet driven by the incident beam is continued by a wall jet, and a second jet is driven by the reflected beam, making an angle with the impinging jet. The flow is also numerically modeled as that of an incompressible fluid undergoing a volumetric acoustic force. This is a classical approach, but the complexity of the acoustic field in the reflection zone, however, makes it difficult to derive an exact force field in this area. Several approximations are thus tested; we show that the observed velocity field only weakly depends on the approximation used in this small region. The numerical model results are in good agreement with the experimental results. The spreading of the jets around their impingement points and the creeping of the wall jets along the walls are observed to allow the interaction of the flow with a large wall surface, which can even extend to the corners of the tank; this could be an interesting feature for applications requiring efficient heat and mass transfer at the wall. More fundamentally, the velocity field is shown to have both similarities and differences with the velocity field in a classical centered acoustic streaming jet. In particular its magnitude exhibits a fairly good agreement with a formerly derived scaling law based on the balance of the acoustic forcing with the inertia due to the flow acceleration along the beam axis. PMID:26907890

  1. Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures

    KAUST Repository

    Xiao, Bingmu

    2013-05-01

    In this thesis, wave propagation through acoustic materials with subwavelength slits structures is studied. Guided by the findings, acoustic wave focusing is achieved with a specific material design. By using a parameter retrieving method, an effective medium theory for a slab with periodic subwavelength cut-through slits is successfully derived. The theory is based on eigenfunction solutions to the acoustic wave equation. Numerical simulations are implemented by the finite-difference time-domain (FDTD) method for the two-dimensional acoustic wave equation. The theory provides the effective impedance and refractive index functions for the equivalent medium, which can reproduce the transmission and reflection spectral responses of the original structure. I analytically and numerically investigate both the validity and limitations of the theory, and the influences of material and geometry on the effective spectral responses are studied. Results show that large contrasts in impedance and density are conditions that validate the effective medium theory, and this approximation displays a better accuracy for a thick slab with narrow slits in it. Based on the effective medium theory developed, a design of a at slab with a snake shaped" subwavelength structure is proposed as a means of achieving acoustic focusing. The property of focusing is demonstrated by FDTD simulations. Good agreement is observed between the proposed structure and the equivalent lens pre- dicted by the theory, which leads to robust broadband focusing by a thin at slab.

  2. Acousto-plasmofluidics: Acoustic modulation of surface plasmon resonance in microfluidic systems

    Science.gov (United States)

    Ahmed, Daniel; Peng, Xiaolei; Ozcelik, Adem; Zheng, Yuebing; Huang, Tony Jun

    2015-09-01

    We acoustically modulated the localized surface plasmon resonances (LSPRs) of metal nanostructures integrated within microfluidic systems. An acoustically driven micromixing device based on bubble microstreaming quickly and homogeneously mixes multiple laminar flows of different refractive indices. The altered refractive index of the mixed fluids enables rapid modulation of the LSPRs of gold nanodisk arrays embedded within the microfluidic channel. The device features fast response for dynamic operation, and the refractive index within the channel is tailorable. With these unique features, our "acousto-plasmofluidic" device can be useful in applications such as optical switches, modulators, filters, biosensors, and lab-on-a-chip systems.

  3. Educational Programme in Nuclear Security

    International Nuclear Information System (INIS)

    The potential of a malicious act involving nuclear or other radioactive material is a continuing worldwide threat. Available data indicate circumstances in which nuclear and other radioactive material are vulnerable to theft, are uncontrolled, or are in unauthorized circulation. States must establish sustainable security measures to prevent such acts and to protect society from nuclear terrorism. Appropriate training and education at all levels and in all relevant organizations and facilities can play a major role in this process. There is increased interest in nuclear applications. Many States have expressed interest in expanding or introducing nuclear power in their country as a result of their own assessment of their energy supply needs, because of climate change, and development requirements. The projected increase in the demand for nuclear energy will increase the number of nuclear reactors worldwide and, consequently, the amount of nuclear material in use. Possible malicious acts involving nuclear or other radioactive material are a real threat. These developments are mirrored by an increase in the use of nuclear techniques in non-power applications. As a result, the need for experts in the area of nuclear security has become of great importance, and both universities and students have shown an increasing interest in nuclear security specialities. In September 2005, the Board of Governors approved a Nuclear Security Plan covering the period 2006-2009. This emphasized, inter alia, the importance of human resource development to assist States in building capacity to establish and maintain appropriate nuclear security to prevent, detect and respond to malicious acts involving nuclear and other radioactive material. The Nuclear Security Plan envisages the development of guidance for an educational programme in nuclear security that could be used by all States. In pursuit of this goal, this publication has been developed to provide advice and assistance to

  4. Academic Training Lecture - Regular Programme

    CERN Multimedia

    PH Department

    2011-01-01

    Regular Lecture Programme 9 May 2011 ACT Lectures on Detectors - Inner Tracking Detectors by Pippa Wells (CERN) 10 May 2011 ACT Lectures on Detectors - Calorimeters (2/5) by Philippe Bloch (CERN) 11 May 2011 ACT Lectures on Detectors - Muon systems (3/5) by Kerstin Hoepfner (RWTH Aachen) 12 May 2011 ACT Lectures on Detectors - Particle Identification and Forward Detectors by Peter Krizan (University of Ljubljana and J. Stefan Institute, Ljubljana, Slovenia) 13 May 2011 ACT Lectures on Detectors - Trigger and Data Acquisition (5/5) by Dr. Brian Petersen (CERN) from 11:00 to 12:00 at CERN ( Bldg. 222-R-001 - Filtration Plant )

  5. Computer programmes for nuclear physics

    International Nuclear Information System (INIS)

    Two programmes for use in the calculation of problems involving the scattering of neutrons, protons or heavier composite particles from nuclei are described. The first, an optical model for the calculation of the elastic, total and absorption cross-sections from an optical potential, includes facilities for automatically finding the appropriate optical potential to describe any given set of experimental data. The second a statistical model for the calculation of inelastic and other compound nucleus scattering processes, according to three different theories, includes level width fluctuation calculations. (U.K.)

  6. le programme SET-Routes

    CERN Document Server

    CERN Audiovisual Service

    2009-01-01

    Les routes de la science sont plus escarpées pour les femmes Le programme SET-Routes, qui visait à sensibiliser les jeunes filles à l’intérêt des carrières scientifiques, a pris fin en avril. Porté par l’EMBL, l’EMBO et le CERN, il a mis en place un réseau de femmes scientifiques, des ambassadrices qui se sont rendues dans les établissements scolaires européens pour parler de leur parcours scientifique.

  7. Programmable Multi-Chip Module

    Science.gov (United States)

    Kautz, David; Morgenstern, Howard; Blazek, Roy J.

    2004-11-16

    A multi-chip module comprising a low-temperature co-fired ceramic substrate having a first side on which are mounted active components and a second side on which are mounted passive components, wherein this segregation of components allows for hermetically sealing the active components with a cover while leaving accessible the passive components, and wherein the passive components are secured using a reflow soldering technique and are removable and replaceable so as to make the multi-chip module substantially programmable with regard to the passive components.

  8. Acoustic communication in plant-animal interactions.

    Science.gov (United States)

    Schöner, Michael G; Simon, Ralph; Schöner, Caroline R

    2016-08-01

    Acoustic communication is widespread and well-studied in animals but has been neglected in other organisms such as plants. However, there is growing evidence for acoustic communication in plant-animal interactions. While knowledge about active acoustic signalling in plants (i.e. active sound production) is still in its infancy, research on passive acoustic signalling (i.e. reflection of animal sounds) revealed that bat-dependent plants have adapted to the bats' echolocation systems by providing acoustic reflectors to attract their animal partners. Understanding the proximate mechanisms and ultimate causes of acoustic communication will shed light on an underestimated dimension of information transfer between plants and animals. PMID:27423052

  9. Modelling of acoustic transmission through perforated layer

    Directory of Open Access Journals (Sweden)

    Lukeš V.

    2007-10-01

    Full Text Available The paper deals with modeling the acoustic transmission through a perforated interface plane separating two halfspaces occupied by the acoustic medium. We considered the two-scale homogenization limit of the standard acoustic problem imposed in the layer with the perforated periodic structure embedded inside. The homogenized transmission conditions govern the interface discontinuity of the acoustic pressure associated with the two halfspaces and the magnitude of the fictitious transversal acoustic velocity. By numerical examples we illustrate this novel approach of modeling the acoustic impedance of perforated interfaces.

  10. Sonification of acoustic emission data

    Science.gov (United States)

    Raith, Manuel; Große, Christian

    2014-05-01

    While loading different specimens, acoustic emissions appear due to micro crack formation or friction of already existing crack edges. These acoustic emissions can be recorded using suitable ultrasonic transducers and transient recorders. The analysis of acoustic emissions can be used to investigate the mechanical behavior of different specimens under load. Our working group has undertaken several experiments, monitored with acoustic emission techniques. Different materials such as natural stone, concrete, wood, steel, carbon composites and bone were investigated. Also the experimental setup has been varied. Fire-spalling experiments on ultrahigh performance concrete and pullout experiments on bonded anchors have been carried out. Furthermore uniaxial compression tests on natural stone and animal bone had been conducted. The analysis tools include not only the counting of events but the analysis of full waveforms. Powerful localization algorithms and automatic onset picking techniques (based on Akaikes Information Criterion) were established to handle the huge amount of data. Up to several thousand events were recorded during experiments of a few minutes. More sophisticated techniques like moment tensor inversion have been established on this relatively small scale as well. Problems are related to the amount of data but also to signal-to-noise quality, boundary conditions (reflections) sensor characteristics and unknown and changing Greens functions of the media. Some of the acoustic emissions recorded during these experiments had been transferred into audio range. The transformation into the audio range was done using Matlab. It is the aim of the sonification to establish a tool that is on one hand able to help controlling the experiment in-situ and probably adjust the load parameters according to the number and intensity of the acoustic emissions. On the other hand sonification can help to improve the understanding of acoustic emission techniques for training

  11. Acoustic constituents of prosodic typology

    Science.gov (United States)

    Komatsu, Masahiko

    Different languages sound different, and considerable part of it derives from the typological difference of prosody. Although such difference is often referred to as lexical accent types (stress accent, pitch accent, and tone; e.g. English, Japanese, and Chinese respectively) and rhythm types (stress-, syllable-, and mora-timed rhythms; e.g. English, Spanish, and Japanese respectively), it is unclear whether these types are determined in terms of acoustic properties, The thesis intends to provide a potential basis for the description of prosody in terms of acoustics. It argues for the hypothesis that the source component of the source-filter model (acoustic features) approximately corresponds to prosody (linguistic features) through several experimental-phonetic studies. The study consists of four parts. (1) Preliminary experiment: Perceptual language identification tests were performed using English and Japanese speech samples whose frequency spectral information (i.e. non-source component) is heavily reduced. The results indicated that humans can discriminate languages with such signals. (2) Discussion on the linguistic information that the source component contains: This part constitutes the foundation of the argument of the thesis. Perception tests of consonants with the source signal indicated that the source component carries the information on broad categories of phonemes that contributes to the creation of rhythm. (3) Acoustic analysis: The speech samples of Chinese, English, Japanese, and Spanish, differing in prosodic types, were analyzed. These languages showed difference in acoustic characteristics of the source component. (4) Perceptual experiment: A language identification test for the above four languages was performed using the source signal with its acoustic features parameterized. It revealed that humans can discriminate prosodic types solely with the source features and that the discrimination is easier as acoustic information increases. The

  12. A novel sensor for monitoring acoustic cavitation. Part I: Concept, theory, and prototype development.

    Science.gov (United States)

    Zeqiri, Bajram; Gélat, Pierre N; Hodnett, Mark; Lee, Nigel D

    2003-10-01

    This paper describes a new concept for an ultrasonic cavitation sensor designed specifically for monitoring acoustic emissions generated by small microbubbles when driven by an applied acoustic field. Its novel features include a hollow, open-ended, cylindrical shape, with the sensor being a right circular cylinder of height 32 mm and external diameter 38 mm. The internal diameter of the sensor is 30 mm; its inner surface is fabricated from a 110-microm layer of piezoelectrically active film whose measurement bandwidth is sufficient to enable acoustic emissions up to and beyond 10 MHz to be monitored. When in use, the sensor is immersed within the liquid test medium and high frequency (megahertz) acoustic emissions occurring within the hollow body of the sensor are monitored. In order to shield the sensor response from events occurring outside the cylinder, the outer surface of the sensor cylinder is encapsulated within a special 4-mm thick polyurethane-based cavitation shield with acoustic properties specifically developed to be minimally perturbing to the 40 kHz applied acoustic field but attenuating to ultrasound generated at megahertz frequencies (plane-wave transmission loss > 30 dB at 1 MHz). This paper introduces the rationale behind the new sensor, describing details of its construction and the materials formulation program undertaken to develop the cavitation shield. PMID:14609074

  13. CALCULATION OF ACOUSTIC EFFICIENCY OF PORTABLE ACOUSTIC SCREEN

    Directory of Open Access Journals (Sweden)

    Aleksandr Skvortsov

    2016-03-01

    Full Text Available The research of influence of life environment adverse factors on physical development and health of population is an actual problem of ecology. The aspects of the most actual problems of the modern world, namely environmental industrial noise pollution are considered in the article. Industrial facilities everywhere have noisy equipment. Noise is a significant factors of negative influenceon people and environment. Combined effects of noise and of other physical pollutions on people may cause amplification of their negative impact. If the noise pollution level from the object in a residential area exceeds the permissible levels (MPL, noise protection measures can be initiated. Today, the most common design decisions for noise protection are sound absorbing construction, noise screens and barriers, acousting housings, soundproff cabins. Many of them are popular, others are less known. The article deals with one of the most wide spread means of noise protection – a portable acoustic screen. The aim of the research is to determine the efficiency of portable acoustic screens. It is shown that the installation of such structures can reduce the average value of the sound level. The authors analyzed acoustic screens as device to reduce noise pollution. The authors offer a potable acoustic screen differing from the used easyness, mobility, minimum price and good sound protective properties. Effectiveness, a sound absorption coefficient and sound conductivity coefficient of a portable acoustic screen are evaluated. The descriptions of the algorithm calculations and the combination of technical solutions have practical originality. The results of the research demonstrate the advantages of the proposed solutions for reducing noise levels in the agro-industrial complex.

  14. My 65 years in acoustics

    Science.gov (United States)

    Beranek, Leo L.

    2001-05-01

    My entry into acoustics began as research assistant to Professor F. V. Hunt at Harvard University. I received my doctorate in 1940 and directed the Electro-Acoustic Laboratory at Harvard from October 1940 until September 1945. In 1947, I became a tenured associate professor at MIT, and, with Richard H. Bolt, formed the consulting firm Bolt and Beranek, that later included Robert B. Newman, becoming BBN. My most significant contributions before 1970 were design of wedge-lined anechoic chambers, systemization of noise reduction in ventilation systems, design of the world's largest muffler for the testing of supersonic jet engines at NASA's Lewis Laboratory in Cleveland, speech interference level, NC noise criterion curves, heading New York Port Authority's noise study that resulted in mufflers on jet aircraft, and steep aircraft climb procedures, and publishing books titled, Acoustical Measurements, Acoustics, Noise Reduction, Noise and Vibration Control, and Music, Acoustics and Architecture. As President of BBN, I supervised the formation of the group that built and operated the ARPANET (1969), which, when split in two (using TCP/IP protocol) became the INTERNET (1984). Since then, I have written two books on Concert Halls and Opera Houses and have consulted on four concert halls and an opera house.

  15. Quality control programme for radiotherapy

    International Nuclear Information System (INIS)

    A 3 years pilot programme started in January 2000 with 33 philanthropic cancer institutions that provides medical services to 60% of the patients from the national social security system. Brazil has today 161 radiotherapy services (144 operating with megavoltage equipment). These 33 institutions are distributed over 19 Brazilian states. The aim of this programme is: To create conditions to allow the participants to apply the radiotherapy with quality and efficacy; To promote up dating courses for the physicians, physicists and technicians of these 33 Institutions. With the following objectives: To recommend dosimetric and radiological protection procedures in order to guarantee the tumor prescribed dose and safe working conditions; To help in establishing and implementing these procedures. The main activities are: local quality control evaluations, postal TLD audits in reference conditions, postal TLD audits in off axis conditions and training. The local quality control program has already evaluated 22 institutions with 43 machines (25 Co-60 and 18 linear accelerators). In these visits we perform dosimetric, electrical, mechanical and safety tests. As foreseen, we found more problems among the old Co-60 machines i.e., field flatness, size, symmetry and relative output factors; lasers positioning system alignment; optical distance indicator; radiation and light field coincidence; optical and mechanical distance indicators agreement, than among the linear accelerators i.e., field flatness and size; lasers positioning system alignment; tray interlocking and wedge filter factors

  16. 2001 - 2002 ACADEMIC TRAINING PROGRAMME

    CERN Multimedia

    Academic Training; Tel. 73127

    2001-01-01

    1ST TERM 1ST OCTOBER - 23 NOVEMBER 2001 LECTURE SERIES FOR POSTGRADUATE STUDENTS The Autumn term of the Academic Training Programme is about to start. As usual, the first term includes lectures primarily dedicated to Post-graduate students. These are meant to help students complement the courses available from their home Universities with lectures on topics close to CERN activities. The lectures are nevertheless open to all CERN staff, and in particular to young Fellows. This year's series include courses on Accelerator Physics, on Field Theory, and on Symmetry Breaking Phenomena in Physics. The course on Accelerators by Dr. Wilson has been a regular feature on the Academic Training programme for many previous editions. This year, the course will be updated to include new sections on Colliders and on future facilities such as the Neutrino Factory. A good introduction to this very successful course can be found in the previous version of these lectures, available from the Web Lecture Archive Project: http://w...

  17. The Programmers' Collective: Fostering Participatory Culture by Making Music Videos in a High School Scratch Coding Workshop

    Science.gov (United States)

    Fields, Deborah; Vasudevan, Veena; Kafai, Yasmin B.

    2015-01-01

    We highlight ways to support interest-driven creation of digital media in Scratch, a visual-based programming language and community, within a high school programming workshop. We describe a collaborative approach, the programmers' collective, that builds on social models found in do-it-yourself and open source communities, but with scaffolding…

  18. Reflections on Enhancing Pre-Service Teacher Education Programmes to Support Inclusion: Perspectives from New Zealand and Australia

    Science.gov (United States)

    Arthur-Kelly, Michael; Sutherland, Dean; Lyons, Gordon; Macfarlane, Sonja; Foreman, Phil

    2013-01-01

    Positive changes to pre-service teacher education programmes (PSTEPs), driven in part by changing worldwide policy frameworks around inclusion, are occurring, albeit slowly. After briefly reviewing international trends and key policy and legislation platforms in New Zealand and Australia, this paper explores some of the challenges in enhancing…

  19. GMES Space Component: Programme overview

    Science.gov (United States)

    Aschbacher, J.; Milagro-Perez, M. P.

    2012-04-01

    The European Union (EU) and the European Space Agency (ESA) have developed the Global Monitoring for Environment and Security (GMES) programme as Europe's answer to the vital need for joined-up data about our climate, environment and security. Through a unique combination of satellite, atmospheric and Earth-based monitoring systems, the initiative will provide new insight into the state of the land, sea and air, providing policymakers, scientists, businesses and the public with accurate and timely information. GMES capabilities include monitoring and forecasting of climatic change, flood risks, soil and coastal erosion, crop and fish resources, air pollution, greenhouse gases, iceberg distribution and snow cover, among others. To accomplish this, GMES has been divided into three main components: Space, In-situ and Services. The Space Component, led by ESA, comprises five types of new satellites called Sentinels that are being developed by ESA specifically to meet the needs of GMES, the first of which to be launched in 2013. These missions carry a range of technologies, such as radar and multi-spectral imaging instruments for land, ocean and atmospheric monitoring. In addition, access to data from the so-called Contributing Missions guarantees that European space infrastructure is fully used for GMES. An integrated Ground Segment ensures access to Sentinels and Contributing Missions data. The in-situ component, under the coordination of the European Environment Agency (EEA), is composed of atmospheric and Earth based monitoring systems, and based on established networks and programmes at European and international levels. The European Commission is in charge of implementing the services component of GMES and of leading GMES overall. GMES services, fed with data from the Space and In-situ components, will provide essential information in five main domains, atmosphere, ocean and land monitoring as well as emergency response and security. Climate change has been added

  20. Teaching in English-medium programmes

    DEFF Research Database (Denmark)

    Lauridsen, Karen M.; Cozart, Stacey Marie

    professors when they develop their own teaching in connection with the following EduIT module of the teacher training programme. In our contribution to the symposium we will briefly present and discuss the what, why and how of this module as well as the participants’ reaction to it, based on the evaluations......This contribution describes and discusses the module Teaching in English-medium programmes, an elective module offered as part of the teacher training programme for assistant professors (“adjunktpædagogikum”) at Aarhus University. In order to complete the whole programme, assistant professors must...... have at least one such elective module (http://upnet.au.dk/adjunktkursus/). Aarhus University offers the teacher training programme in Danish and in English for international faculty. Teaching in English-medium programmes is part of the Danish track, but taught through English. Building...

  1. Sonic ingredients in television food programmes

    OpenAIRE

    Charlotte Rørdam Larsen

    2013-01-01

    The main focus of this article is the use, significance, and role of sound in food and food travel programmes, exemplified by cooking programmes broadcast on Danish television – public service and commercial channels. The aim is to demonstrate how sound and music in this kind of programme plays an important part mediating both the cooking and the kitchen as wellordered and well organized. The use of music represents flow, but refers also to locality, globality and identity, and is often linke...

  2. The Parent Champion Programme: independent evaluation

    OpenAIRE

    Durrant, J. A.

    2013-01-01

    The Parent Champion Programme is a personal development course which was piloted in two Medway Children's Centres by 'Every Family Matters' from April 2011 - April 2013, sponsored by Big Lottery funding. This evaluation of the programme examines evidence including parents' testimonies, questionnaire data and reports from professionals including Children's Centre Managers. The programme has resulted in some profound improvements for parents and vulnerable families including a 'stepping d...

  3. Postgraduate Medical Ultrasound Programme: Have we Flipped?

    OpenAIRE

    Harrison, G; Harris, A

    2014-01-01

    In recent years due to technological advances, innovative curriculum design has been central to the developments within many health care education programmes. The Medical Ultrasound programme at City University London has been no exception. To enhance the face to face learning time within the part-time postgraduate programme a method of blended learning was developed, which involves on-line lectures and guided self-study, supported by interactive film viewing sessions, group discussions, simu...

  4. Factors Affecting Detection Probability of Acoustic Tags in Coral Reefs

    KAUST Repository

    Bermudez, Edgar F.

    2012-05-01

    Acoustic telemetry is an important tool for studying the movement patterns, behaviour, and site fidelity of marine organisms; however, its application is challenged in coral reef environments where complex topography and intense environmental noise interferes with acoustic signals, and there has been less study. Therefore, it is particularly critical in coral reef telemetry studies to first conduct a long-term range test, a tool that provides informa- tion on the variability and periodicity of the transmitter detection range and the detection probability. A one-month range test of a coded telemetric system was conducted prior to a large-scale tagging project investigating the movement of approximately 400 fishes from 30 species on offshore coral reefs in the central Red Sea. During this range test we determined the effect of the following factors on transmitter detection efficiency: distance from receiver, time of day, depth, wind, current, moon-phase and temperature. The experiment showed that biological noise is likely to be responsible for a diel pattern of -on average- twice as many detections during the day as during the night. Biological noise appears to be the most important noise source in coral reefs overwhelming the effect of wind-driven noise, which is important in other studies. Detection probability is also heavily influenced by the location of the acoustic sensor within the reef structure. Understanding the effect of environmental factors on transmitter detection probability allowed us to design a more effective receiver array for the large-scale tagging study.

  5. Direct Intracochlear Acoustic Stimulation Using a PZT Microactuator

    Directory of Open Access Journals (Sweden)

    Chuan Luo

    2015-11-01

    Full Text Available Combined electric and acoustic stimulation has proven to be an effective strategy to improve hearing in some cochlear implant users. We describe an acoustic microactuator to directly deliver stimuli to the perilymph in the scala tympani. The 800 µm by 800 µm actuator has a silicon diaphragm driven by a piezoelectric thin film (e.g., lead-zirconium-titanium oxide or PZT. This device could also be used as a component of a bimodal acoustic-electric electrode array. In the current study, we established a guinea pig model to test the actuator for its ability to deliver auditory signals to the cochlea in vivo. The actuator was placed through the round window of the cochlea. Auditory brainstem response (ABR thresholds, peak latencies, and amplitude growth were calculated for an ear canal speaker versus the intracochlear actuator for tone burst stimuli at 4, 8, 16, and 24 kHz. An ABR was obtained after removal of the probe to assess loss of hearing related to the procedure. In some animals, the temporal bone was harvested for histologic analysis of cochlear damage. We show that the device is capable of stimulating ABRs in vivo with latencies and growth functions comparable to stimulation in the ear canal. Further experiments will be necessary to evaluate the efficiency and safety of this modality in long-term auditory stimulation and its ability to be integrated with conventional cochlear implant arrays.

  6. Acoustic Signal based Traffic Density State Estimation using SVM

    Directory of Open Access Journals (Sweden)

    Prashant Borkar

    2013-06-01

    Full Text Available Based on the information present in cumulative acoustic signal acquired from a roadside-installed single microphone, this paper considers the problem of vehicular traffic density state estimation. The occurrence and mixture weightings of traffic noise signals (Tyre, Engine, Air Turbulence, Exhaust, and Honks etc are determined by the prevalent traffic density conditions on the road segment. In this work, we extract the short-term spectral envelope features of the cumulative acoustic signals using MFCC (Mel-Frequency Cepstral Coefficients. Support Vector Machines (SVM is used as classifier is used to model the traffic density state as Low (40 Km/h and above, Medium (20-40 Km/h, and Heavy (0-20 Km/h. For the developing geographies where the traffic is non-lane driven and chaotic, other techniques (magnetic loop detectors are inapplicable. SVM classifier with different kernels are used to classify the acoustic signal segments spanning duration of 20–40 s, which results in average classification accuracy of 96.67% for Quadratic kernel function and 98.33% for polynomial kernel function, when entire frames are considered for classification.

  7. Acoustic metasurface with hybrid resonances.

    Science.gov (United States)

    Ma, Guancong; Yang, Min; Xiao, Songwen; Yang, Zhiyu; Sheng, Ping

    2014-09-01

    An impedance-matched surface has the property that an incident wave generates no reflection. Here we demonstrate that by using a simple construction, an acoustically reflecting surface can acquire hybrid resonances and becomes impedance-matched to airborne sound at tunable frequencies, such that no reflection is generated. Each resonant cell of the metasurface is deep-subwavelength in all its spatial dimensions, with its thickness less than the peak absorption wavelength by two orders of magnitude. As there can be no transmission, the impedance-matched acoustic wave is hence either completely absorbed at one or multiple frequencies, or converted into other form(s) of energy, such as an electrical current. A high acoustic-electrical energy conversion efficiency of 23% is achieved. PMID:24880731

  8. Acoustic Localization with Infrasonic Signals

    Science.gov (United States)

    Threatt, Arnesha; Elbing, Brian

    2015-11-01

    Numerous geophysical and anthropogenic events emit infrasonic frequencies (wind turbines and tornadoes. These sounds, which cannot be heard by the human ear, can be detected from large distances (in excess of 100 miles) due to low frequency acoustic signals having a very low decay rate in the atmosphere. Thus infrasound could be used for long-range, passive monitoring and detection of these events. An array of microphones separated by known distances can be used to locate a given source, which is known as acoustic localization. However, acoustic localization with infrasound is particularly challenging due to contamination from other signals, sensitivity to wind noise and producing a trusted source for system development. The objective of the current work is to create an infrasonic source using a propane torch wand or a subwoofer and locate the source using multiple infrasonic microphones. This presentation will present preliminary results from various microphone configurations used to locate the source.

  9. Acoustic multivariate condition monitoring - AMCM

    Energy Technology Data Exchange (ETDEWEB)

    Rosenhave, P.E. [Vestfold College, Maritime Dept., Toensberg (Norway)

    1997-12-31

    In Norway, Vestfold College, Maritime Department presents new opportunities for non-invasive, on- or off-line acoustic monitoring of rotating machinery such as off-shore pumps and diesel engines. New developments within acoustic sensor technology coupled with chemometric data analysis of complex signals now allow condition monitoring of hitherto unavailable flexibility and diagnostic specificity. Chemometrics paired with existing knowledge yields a new and powerful tool for condition monitoring. By the use of multivariate techniques and acoustics it is possible to quantify wear and tear as well as predict the performance of working components in complex machinery. This presentation describes the AMCM method and one result of a feasibility study conducted onboard the LPG/C `Norgas Mariner` owned by Norwegian Gas Carriers as (NGC), Oslo. (orig.) 6 refs.

  10. Acoustic Communication for Medical Nanorobots

    CERN Document Server

    Hogg, Tad

    2012-01-01

    Communication among microscopic robots (nanorobots) can coordinate their activities for biomedical tasks. The feasibility of in vivo ultrasonic communication is evaluated for micron-size robots broadcasting into various types of tissues. Frequencies between 10MHz and 300MHz give the best tradeoff between efficient acoustic generation and attenuation for communication over distances of about 100 microns. Based on these results, we find power available from ambient oxygen and glucose in the bloodstream can readily support communication rates up to 10,000 bits/second between micron-sized robots. We discuss techniques, such as directional acoustic beams, that can increase this rate. The acoustic pressure fields enabling this communication are unlikely to damage nearby tissue, and short bursts at considerably higher power could be of therapeutic use.

  11. On Architectural Acoustics Design using Computer Simulation

    DEFF Research Database (Denmark)

    Schmidt, Anne Marie Due; Kirkegaard, Poul Henning

    2004-01-01

    The acoustical quality of a given building, or space within the building, is highly dependent on the architectural design. Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in the architectural acoustic and the emergence of potent...... room acoustic simulation programs it is now possible to subjectively analyze and evaluate acoustic properties prior to the actual construction of a facility. With the right tools applied, the acoustic design can become an integrated part of the architectural design process. The aim of the present paper...... is to investigate the field of application an acoustic simulation program can have during an architectural acoustics design process. A case study is carried out in order to represent the iterative working process of an architect. The working process is divided into five phases and represented by typical results...

  12. Acoustojet: acoustic analogue of photonic jet phenomenon

    CERN Document Server

    Minin, Igor V

    2016-01-01

    It has been demonstrated for the first time that an existence of acoustic analogue of photonic jet phenomenon, called acoustojet, providing for subwavelength localization of acoustic field in the shadow area of arbitrary 3D penetrable mesoscale particle, is possible.

  13. Golden Gate and Pt. Reyes Acoustic Detections

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains detections of acoustic tagged fish from two general locations: Golden Gate (east and west line) and Pt. Reyes. Several Vemco 69khz acoustic...

  14. Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis

    Science.gov (United States)

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis On this page: ... more information about vestibular schwannomas? What is a vestibular schwannoma (acoustic neuroma)? Inner ear with vestibular schwannoma ( ...

  15. On the Synchronization of Acoustic Gravity Waves

    Science.gov (United States)

    Lonngren, Karl E.; Bai, Er-Wei

    Using the model proposed by Stenflo, we demonstrate that acoustic gravity waves found in one region of space can be synchronized with acoustic gravity waves found in another region of space using techniques from modern control theory.

  16. Acoustic network event classification using swarm optimization

    Science.gov (United States)

    Burman, Jerry

    2013-05-01

    Classifying acoustic signals detected by distributed sensor networks is a difficult problem due to the wide variations that can occur in the transmission of terrestrial, subterranean, seismic and aerial events. An acoustic event classifier was developed that uses particle swarm optimization to perform a flexible time correlation of a sensed acoustic signature to reference data. In order to mitigate the effects from interference such as multipath, the classifier fuses signatures from multiple sensors to form a composite sensed acoustic signature and then automatically matches the composite signature with reference data. The approach can classify all types of acoustic events but is particularly well suited to explosive events such as gun shots, mortar blasts and improvised explosive devices that produce an acoustic signature having a shock wave component that is aperiodic and non-linear. The classifier was applied to field data and yielded excellent results in terms of reconstructing degraded acoustic signatures from multiple sensors and in classifying disparate acoustic events.

  17. Building a global business continuity programme.

    Science.gov (United States)

    Lazcano, Michael

    2014-01-01

    Business continuity programmes provide an important function within organisations, especially when aligned with and supportive of the organisation's goals, objectives and organisational culture. Continuity programmes for large, complex international organisations, unlike those for compact national companies, are more difficult to design, build, implement and maintain. Programmes for international organisations require attention to structural design, support across organisational leadership and hierarchy, seamless integration with the organisation's culture, measured success and demonstrated value. This paper details practical, but sometimes overlooked considerations for building successful global business continuity programmes. PMID:24854730

  18. Dataudveksling mellem CAD og CAE programmer

    DEFF Research Database (Denmark)

    Sørensen, Torben; Conrad, Finn

    2001-01-01

    Når mange forskelligartede programmer benyttes til beregninger og anden databehandling på samme modeller er det nødvendig at udveksle modellerne mellem disse forskellige programmer. Biler og skibe bliver f.eks. typisk designet i 3D CAD systemer, mens CAD modellerne herefter anvendes i andre...... dedikerede IT-systemer i forbindelse montageplanlægningen, svejseplanlægningen, robotprogrammeringen mm. der således her et behov for at udveksle CAD modellen mellem de forskellige programmer. Udveksling af information mellem forskellige programmer og systemer kræver såvel en fælles specifikation af det...

  19. Building a global business continuity programme.

    Science.gov (United States)

    Lazcano, Michael

    2014-01-01

    Business continuity programmes provide an important function within organisations, especially when aligned with and supportive of the organisation's goals, objectives and organisational culture. Continuity programmes for large, complex international organisations, unlike those for compact national companies, are more difficult to design, build, implement and maintain. Programmes for international organisations require attention to structural design, support across organisational leadership and hierarchy, seamless integration with the organisation's culture, measured success and demonstrated value. This paper details practical, but sometimes overlooked considerations for building successful global business continuity programmes.

  20. Ethical Issues for Community College Student Programmers.

    Science.gov (United States)

    Friedrich, Sue

    2002-01-01

    Discusses examples of unique ethical issues faced by community college student programmers: member commitment, poor program attendance and lack of programming board diversity, and conflicts of interest (EV)

  1. Nuclear power programmes in developing countries

    International Nuclear Information System (INIS)

    The paper on ''Nuclear power programmes in developing countries'' is a report to the IAEA by a Senior Expert Group. A description is given of the requirements for a successful nuclear power programme, including the constraints that developing countries might face in the introduction and execution of the programme. The group attempted to identify the main issues affecting the financing of nuclear power projects and suggested specific actions that could be undertaken in order to reduce economic and financial risks. The various issues were discussed under the topic headings:-programme-project-related factors, investment climate, financing plan, export credits and creditworthiness. (U.K.)

  2. A leadership programme for critical care.

    Science.gov (United States)

    Crofts, Linda

    2006-08-01

    This paper describes the genesis, design and implementation of a leadership programme for critical care. This was an initiative funded by the National Health Service (NHS) Nursing Leadership Project and had at the core of its design flexibility to meet the needs of the individual hospitals, which took part in it. Participation was from the multi-disciplinary critical care team. Six NHS hospitals took part in the programme which was of 20 days duration and took place on hospital sites. The programme used the leadership model of as its template and had a number of distinct components; a baseline assessment, personal development, principles of leadership and critical case reviews. The programme was underpinned by three themes; working effectively in multi-professional teams to provide patient focussed care, managing change through effective leadership and developing the virtual critical care service. Each group set objectives pertinent to their own organisation's needs. The programme was evaluated by a self-reporting questionnaire; group feedback and feedback from stakeholders. Programme evaluation was positive from all the hospitals but it was clear that the impact of the programme varied considerably between the groups who took part. It was noted that there was some correlation between the success of the programme and organisational 'buy in' as well as the organisational culture within which the participants operated. A key feature of the programme success was the critical case reviews, which were considered to be a powerful learning tool and medium for group learning and change management. PMID:16621563

  3. Survey of radiation protection programmes for transport

    International Nuclear Information System (INIS)

    The survey of radiation protection programmes for transport has been jointly performed by three scientific organisations I.P.S.N. (France), G.R.S. ( Germany), and N.R.P.B. (United kingdom) on behalf of the European Commission and the pertaining documentation summarises the findings and conclusions of the work that was undertaken with the principal objectives to provide guidance on the establishment, implementation and application of radiation protection programmes for the transport of radioactive materials by operators and the assessment and evaluation of such programmes by the competent authority and to review currently existing radiation protection programmes for the transport of radioactive materials. (N.C.)

  4. A leadership programme for critical care.

    Science.gov (United States)

    Crofts, Linda

    2006-08-01

    This paper describes the genesis, design and implementation of a leadership programme for critical care. This was an initiative funded by the National Health Service (NHS) Nursing Leadership Project and had at the core of its design flexibility to meet the needs of the individual hospitals, which took part in it. Participation was from the multi-disciplinary critical care team. Six NHS hospitals took part in the programme which was of 20 days duration and took place on hospital sites. The programme used the leadership model of as its template and had a number of distinct components; a baseline assessment, personal development, principles of leadership and critical case reviews. The programme was underpinned by three themes; working effectively in multi-professional teams to provide patient focussed care, managing change through effective leadership and developing the virtual critical care service. Each group set objectives pertinent to their own organisation's needs. The programme was evaluated by a self-reporting questionnaire; group feedback and feedback from stakeholders. Programme evaluation was positive from all the hospitals but it was clear that the impact of the programme varied considerably between the groups who took part. It was noted that there was some correlation between the success of the programme and organisational 'buy in' as well as the organisational culture within which the participants operated. A key feature of the programme success was the critical case reviews, which were considered to be a powerful learning tool and medium for group learning and change management.

  5. Dust acoustic instability in a strongly coupled dusty plasma

    Science.gov (United States)

    Rosenberg, M.; Kalman, G. J.; Hartmann, P.; Goree, J.

    2013-10-01

    Dusty plasmas are plasmas containing charged micron to sub-micron size dust grains (solid particulates). Because the grains can be multiply charged and are much more massive than the ions, the presence of dust can lead to novel waves such as the dust acoustic wave, which is a compressional wave that can be excited by a flow of ions that is driven by an electric field. Moreover, the large dust charge can result in strong Coulomb coupling between the dust grains, where the electrostatic energy between neighboring grains is larger than their thermal (kinetic) energy. When the coupling between dust grains is strong, but not large enough for crystallization, the dust is in the strongly coupled liquid phase. This poster theoretically investigates the dust acoustic instability, which is driven by sub-thermal ion flow, in a three-dimensional dusty plasma in the strongly coupled liquid phase. It is found that strong coupling enhances the instability. The application is to microgravity experiments with dusty plasma planned for the PK-4 and PlasmaLab instruments, which are in development for the International Space Station. Microgravity conditions enable the preparation of dust clouds under these sub-thermal ion flow conditions by avoiding the need for strong electric fields to levitate the dust grains.

  6. Why do tougher caseworkers increase employment? The role of programme assignment as a causal mechanism

    DEFF Research Database (Denmark)

    Huber, Martin; Lechner, Michael; Mellace, Giovanni

    2016-01-01

    find that the positive employment effects of less accommodating caseworkers are not driven by a particularly effective mix of labour market programmes, but rather by other dimensions of the counselling process, possibly including threat effects of sanctions and pressure to accept jobs.......Previous research found that less accommodating caseworkers are more successful in placing unemployed workers into employment. This paper explores the causal mechanisms behind this result using semiparametric mediation analysis. Analysing rich linked jobseeker-caseworker data for Switzerland, we...

  7. Collision and recombination driven instabilities in variable charged dusty plasmas

    Indian Academy of Sciences (India)

    S Bal; M Bose

    2013-04-01

    The dust-acoustic instability driven by recombination of electrons and ions on the surface of charged and variably-charged dust grains as well as by collisions in dusty plasmas with significant pressure of background neutrals have been theoretically investigated. The recombination driven instability is shown to be dominant in the long wavelength regime even in the presence of dust-neutral and ion-neutral collisions, while in the shorter wavelength regime, the dust-neutral collision is found to play a major role. In an earlier research work, the dust-neutral collision was neglected in comparison to the effect due to the recombination for estimating the dust-acoustic instability; later the other report shows that the recombination effect is negligible in the presence of dust-neutral collisions. In line of this present situation our investigation revealed that the recombination is more important than dust-neutral collisions in laboratory plasma and fusion plasma, while the dust-neutral collision frequency is dominant in the interstellar plasmas. The effects of ion and dust densities and ion streaming on the recombination and collision driven mode in parameter regimes relevant for many experimental studies on dusty plasmas have also been calculated.

  8. CT findings of acoustic neuroma

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Do Choul; Lee, Jae Mun; Shinn, Kyung Sub; Bahk, Yong Whee [Catholic Univ., Seoul (Korea, Republic of)

    1987-10-15

    Computed Tomography (CT) is very accurate in evaluating the location, size, shape and extension of acoustic neuroma. We analysed CT findings of 23 acoustic neuromas seen at Department of Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College during the period of from January 1981 to June 1987. 1. Five (22%) were men and 18 (78%) were women with the high incidence occurring in the 4th and 5th decades. 2. Twenty two cases were diagnosed satisfactorily by CT examinations which included axial, coronal and reconstruction images. One with the smallest dimension of 8 mm in diameter could not be detected by the conventional CT scan. But is could be seen after metrizamide cisternography. mean size of the tumor masses was estimated 3.6 cm in diameter. 3. The shape of the tumor was oval in 50%, round in 27% and lobulated in 23%. The masses were presented as hypodense in 50%, isodense in 32% and hyperdense in 18%. All tumors were extended from the internal acoustic and toward the cerebellopontine angle. The internal acoustic canal was widened in 77%. Hydrocephalus was associated in 45%. Widening of cerebellopontine angle cistern was noted in 50%. 4. After contrast infusion the tumors were enhanced markedly in 45%, moderately in 32% and mildly in 23%. The enhanced pattern was homogeneous in 41%, mixed in 41% and rim in 18%. The margin of the tumors was sharply defined in 82%. The tumors were attached to the petrous bone with acute angle in 73%. Cystic change within the tumor was found in 27%. The peritumoral edema was noted in 45%. In conclusion, CT is of most effective modalities to evaluate size, shape, extent and internal architecture of acoustic neuroma as well as relationship with adjacent anatomic structures including the internal acoustic canal.

  9. Acoustically-Induced Electrical Signals

    Science.gov (United States)

    Brown, S. R.

    2014-12-01

    We have observed electrical signals excited by and moving along with an acoustic pulse propagating in a sandstone sample. Using resonance we are now studying the characteristics of this acousto-electric signal and determining its origin and the controlling physical parameters. Four rock samples with a range of porosities, permeabilities, and mineralogies were chosen: Berea, Boise, and Colton sandstones and Austin Chalk. Pore water salinity was varied from deionized water to sea water. Ag-AgCl electrodes were attached to the sample and were interfaced to a 4-wire electrical resistivity system. Under computer control, the acoustic signals were excited and the electrical response was recorded. We see strong acoustically-induced electrical signals in all samples, with the magnitude of the effect for each rock getting stronger as we move from the 1st to the 3rd harmonics in resonance. Given a particular fluid salinity, each rock has its own distinct sensitivity in the induced electrical effect. For example at the 2nd harmonic, Berea Sandstone produces the largest electrical signal per acoustic power input even though Austin Chalk and Boise Sandstone tend to resonate with much larger amplitudes at the same harmonic. Two effects are potentially responsible for this acoustically-induced electrical response: one the co-seismic seismo-electric effect and the other a strain-induced resistivity change known as the acousto-electric effect. We have designed experimental tests to separate these mechanisms. The tests show that the seismo-electric effect is dominant in our studies. We note that these experiments are in a fluid viscosity dominated seismo-electric regime, leading to a simple interpretation of the signals where the electric potential developed is proportional to the local acceleration of the rock. Toward a test of this theory we have measured the local time-varying acoustic strain in our samples using a laser vibrometer.

  10. Absorption boundary conditions for geomertical acoustics

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2012-01-01

    Defining accurate acoustical boundary conditions is of crucial importance for room acoustic simulations. In predicting sound fields using phased geometrical acoustics methods, the absorption coefficients or surface impedances of the boundary surfaces can be used, but no guideline has been developed...... solutions. Two rectangular rooms with uniform and non-uniform absorption distributions are tested. It is concluded that the impedance and random incidence absorption boundary conditions produce reasonable results with some exceptions at low frequencies for acoustically soft materials....

  11. Acoustic concerns related to multi cultural societies

    OpenAIRE

    Gade, Anders Christian

    2001-01-01

    Immigration has increased cultural diversity in western societies. The process of integrating immigrants into their host countries can be smoothed if acousticians learn to recognize (1) the acoustic traditions of immigrant cultures and (2) the specific acoustic needs of the new society members. Two related projects are discussed. The ``Cahrisma'' project (Conservation of Acoustical Heritage by the Revival and Identification of the Sinan's Mosque Acoustics) is sponsored by the European Commiss...

  12. Biomass programme: Overview of the 2006 Swiss research programme; Programm Biomasse. Ueberblicksbericht zum Forschungsprogramm 2006

    Energy Technology Data Exchange (ETDEWEB)

    Binggeli, D.; Guggisberg, B.

    2007-07-01

    This report for the Swiss Federal Office of Energy (SFOE) reviews work done within the framework of the Swiss biomass research programme in 2006. The programme concentrates on the efficient conversion of biomass into heat, electrical power and motor fuels. Projects concerned with the optimisation of processes are reported on, including low-particle-emission systems, control systems for bivalent heating installations, use of demanding biomass fuels, combined pellets and solar heating systems and the elimination of ammonia emissions. In the material flow area, measurement campaigns, organic pollutants in compost, the effects of fermented wastes in agriculture and methane losses in biogas conditioning are reported on. New conversion technologies are reviewed, including hydro-thermal gasification, plant-oil fuelled combined heat and power units, flameless burners and catalytic direct liquefaction. In the area of basics, studies and concepts, eco-balances and life-cycle analyses are reported on; the production of synthetic natural gas and the influence of combustion particles are discussed and decentralised power generation from solid biomass is reported on. National and international co-operation is reviewed. The report is concluded with a review of eight pilot and demonstration projects, a review of work to be done in 2007 and a list of research and demonstration projects.

  13. Acoustic design by topology optimization

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard; Jensen, Jakob Søndergaard; Sigmund, Ole

    2008-01-01

    To bring down noise levels in human surroundings is an important issue and a method to reduce noise by means of topology optimization is presented here. The acoustic field is modeled by Helmholtz equation and the topology optimization method is based on continuous material interpolation functions...... in the density and bulk modulus. The objective function is the squared sound pressure amplitude. First, room acoustic problems are considered and it is shown that the sound level can be reduced in a certain part of the room by an optimized distribution of reflecting material in a design domain along the ceiling...

  14. Physical foundations of technical acoustics

    CERN Document Server

    Malecki, I

    1969-01-01

    Physical Foundations of Technical Acoustics discusses theoretical foundations of acoustical engineering. It is not so much a technical compendium as a systematic statement of physical laws so conceived that technologists might find in it all the information they need to become acquainted with the physical meaning and mathematical expression of phenomena they encounter in their work. To facilitate the acquirement of notions, which lie beyond a layman's grasp, the plan of narration adopted consists in beginning with the simplest idealized cases and then gradually moving on to the truest possibl

  15. Acoustic characterization of rehabilitated cloisters

    OpenAIRE

    A. P. O. Carvalho; S. R. C. Vilela

    2008-01-01

    This paper presents the results of field measurements in eight rehabilitated cloisters of old monasteries in Portugal (length: 20 to 35 m and height: 3.3 to 6.3 m) regarding their acoustic behavior to two objective parameters: RT and RASTI. The goal is to characterize the acoustic effect of the rehabilitation done on theses spaces to adapt them to new uses. All these cloisters had recently their galleries#8217; openings to the central yard closed with glass panels. Simple formulas were obtain...

  16. Norwegian participation in the IEA Heat Pump Programme Annex 34 - final report

    Energy Technology Data Exchange (ETDEWEB)

    Nordtvedt, S.R.

    2012-07-01

    This report is the Norwegian team contribution to Task A within the IEA Heat Pumps Programme Annex 34 on #Left Double Quotation Mark#Thermally driven heat pumps#Right Double Quotation Mark#. It aims to give an overview of the thermally driven heat pump (TDHP) and chiller (TDC) market, recent developments in the area of TDHP and TDC, as well as to give an outlook of the progress of this technology. There are no Norwegian manufacturers on the TDHP market. There are only seven existing thermally driven absorption system installations in Norway. Three are district heat driven water/LiBr chillers, one is a steam driven water/LiBr chiller, one water/LiBr heat pump for flue gas condensation in a wood chip heating unit, and two gas driven ammonia-water chillers. The future market for thermally driven heat pumps and chillers in Norway is expected to be in combination of biomass, district heat or waste heat. (Author)

  17. Acoustic Test Characterization of Melamine Foam for Usage in NASA's Payload Fairing Acoustic Attenuation Systems

    Science.gov (United States)

    Hughes, William O.; McNelis, Anne M.; McNelis, Mark E.

    2014-01-01

    The external acoustic liftoff levels predicted for NASA's future heavy lift launch vehicles are expected to be significantly higher than the environment created by today's commercial launch vehicles. This creates a need to develop an improved acoustic attenuation system for future NASA payload fairings. NASA Glenn Research Center initiated an acoustic test series to characterize the acoustic performance of melamine foam, with and without various acoustic enhancements. This testing was denoted as NEMFAT, which stands for NESC Enhanced Melamine Foam Acoustic Test, and is the subject of this paper. Both absorption and transmission loss testing of numerous foam configurations were performed at the Riverbank Acoustical Laboratory in July 2013. The NEMFAT test data provides an initial acoustic characterization and database of melamine foam for NASA. Because of its acoustic performance and lighter mass relative to fiberglass blankets, melamine foam is being strongly considered for use in the acoustic attenuation systems of NASA's future launch vehicles.

  18. Calculating room acoustic parameters from pseudo-impulsive acoustic sources

    Science.gov (United States)

    San Martin, Maria L.; Vela, Antonio; San Martin, Ricardo; Arana, Miguel A.

    2002-11-01

    The impulse response function provides complete information to predict the acoustic response of a room to an acoustic input of arbitrary characteristics. At this job study, small explosions of firecrackers are proposed to be used as pseudo-impulsive acoustics sources to determine some acoustic parameters of a room such as reverberation time, definition, and clarity, comparing these results to those obtained with other techniques. A previous characterization of these sources allows us to state that they can be used for this purpose because they are, in practice, omnidirectional, their temporary pattern is highly repetitive and their spectral power is, as well, repetitive and with enough power in octave bands from 125 Hz to 8 kHz. If the linear time-invariant system impulse response h(t) is known, output signal s(t) regarding any arbitrary signal s(t) can be obtained. For our pseudo-impulsive sources, the output signal s(t) has been taken as impulse response h(t). Using the integrated impulse response method suggested by Schroeder, it has been stated that both the mean values and standard deviations for some parameters are practically identical to results obtained with other usual techniques. (To be presented in Spanish.)

  19. The Driven Spinning Top

    Science.gov (United States)

    Grosu, Ioan; Featonby, David

    2016-01-01

    This driven top is quite a novelty and can, with some trials, be made using the principles outlined here. This new top has many applications in developing both understanding and skills and these are detailed in the article. Depending on reader's available time and motivation they may feel an urge to make one themselves, or simply invest a few…

  20. Design of acoustic devices by topology optimization

    DEFF Research Database (Denmark)

    Sigmund, Ole; Jensen, Jakob Søndergaard

    2003-01-01

    The goal of this study is to design and optimize structures and devices that are subjected to acoustic waves. Examples are acoustic lenses, sound walls, waveguides and loud speakers. We formulate the design problem as a topology optimization problem, i.e. distribute material in a design domain...... such that the acoustic response is optimized....

  1. Aero-acoustic Computations of Wind Turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Michelsen, Jess; Sørensen, Jens Nørkær

    2002-01-01

    A numerical algorithm for acoustic noise generation is extended to 3D flows. The approach involves two parts comprising a viscous incompressible flow part and an inviscid acoustic part. In order to simulate noise generated from a wind turbine, the incompressible and acoustic equations are written...

  2. Predicting and auralizing acoustics in classrooms

    DEFF Research Database (Denmark)

    Christensen, Claus Lynge

    2005-01-01

    Although classrooms have fairly simple geometries, this type of room is known to cause problems when trying to predict their acoustics using room acoustics computer modeling. Some typical features from a room acoustics point of view are: Parallel walls, low ceilings (the rooms are flat), uneven...

  3. 2002 - 2003 ACADEMIC TRAINING PROGRAMME

    CERN Multimedia

    Françoise Benz

    2002-01-01

    1st TERM : November - December 2002   LECTURE SERIES FOR POSTGRADUATE STUDENTS 18, 19, 20, 21, 22 November 2002 Telling the Truth with Statistics by R. Barlow / Univ. of Manchester, UK 11:00-12:00 - Auditorium, bldg. 500     REGULAR LECTURE PROGRAMME 2, 3, 4, 5 December 2002 Introduction to String Theory by W. Lerche / CERN-TH 11:00-12:00 - Auditorium, bldg. 500 The lectures are open to all those interested, without application. The abstract of the lectures, as well as any change to the above information (title, dates, time, place etc.) will be published in the CERN bulletin, the WWW, and by Notices before each term and for each series of lectures. Françoise Benz Tel. 73127 francoise.benz@cern.ch

  4. Field Evaluation of Programmable Thermostats

    Energy Technology Data Exchange (ETDEWEB)

    Sachs, O.; Tiefenbeck, V.; Duvier, C.; Qin, A.; Cheney, K.; Akers, C.; Roth, K.

    2012-12-01

    Prior research suggests that poor programmable thermostats usability may prevent their effective use to save energy. We hypothesized that home occupants with a high-usability thermostats would be more likely to use them to save energy than people with a basic thermostat. We randomly installed a high-usability thermostat in half the 77 apartments of an affordable housing complex, installing a basic thermostat in the other half. During the heating season, we collected space temperature and furnace on-off data to evaluate occupant interaction with the thermostats, foremost nighttime setbacks. We found that thermostat usability did not influence energy-saving behaviors, finding no significant difference in temperature maintained among apartments with high- and low-usability thermostats.

  5. Research programme on radioactive wastes

    International Nuclear Information System (INIS)

    This report for the Swiss Federal Department of the Environment, Transport, Energy and Communication (DETEC) takes a look at work done within the framework of the research programme on radioactive wastes. The paper discusses the development of various projects and the associated organisations involved. Both long-term and short-term topics are examined. The long-term aspects of handling radioactive wastes include organisation and financing as well as the preservation of know-how and concepts for marking the repositories. Communication with the general public on the matter is looked at along with public perception, opinion-making and acceptance. Waste storage concepts are looked at in detail and aspects such as environmental protection, monitoring concepts, retrievability and encasement materials are discussed. Finally, ethical and legal aspects of radioactive waste repositories are examined. The paper is completed with appendixes dealing with planning, co-ordination and the responsibilities involved

  6. Power Optimized Programmable Embedded Controller

    Directory of Open Access Journals (Sweden)

    M.Kamaraju

    2010-07-01

    Full Text Available Now a days, power has become a primary consideration in hardware design, and is critical in computersystems especially for portable devices with high performance and more functionality. Clock-gating is themost common technique used for reducing processor’s power. In this work clock gating technique isapplied to optimize the power of fully programmable Embedded Controller (PEC employing RISCarchitecture. The CPU designed supports i smart instruction set, ii I/O port, UART iii on-chip clockingto provide a range of frequencies , iv RISC as well as controller concepts. The whole design is capturedusing VHDL and is implemented on FPGA chip using Xilinx .The architecture and clock gatingtechnique together is found to reduce the power consumption by 33.33% of total power consumed by thischip.

  7. The Immunization Programme In India

    Directory of Open Access Journals (Sweden)

    Sokhey J

    1990-01-01

    Full Text Available The immunization Programme was started in India in 1978 with the objective of reducing the mortality due to vaccine preventable diseases. Immunization coverage levels in infants and pregnant women have increased substantially over the last decade. Immunization coverage levels of 69 to 82% with various vaccines were reported in 1989-90. There is however, a wide disparity in the coverage levels in states and in the districts. While the priority to remains to increase immunization coverage levels, surveillance of vaccine preventable diseases is receiving high priority to identify weak pockets for intensification of immunization services and to document impact. Besides completeness of reporting., emphasis of the surveillance system in many areas has shifted to obtaining information on cases as early as possible to allow epidemiological investigations and effective follow-up action. The achievements in a large number of districts show that the goal of universal immunization, while difficult and challenging, is attainable.

  8. Computer systems a programmer's perspective

    CERN Document Server

    Bryant, Randal E

    2016-01-01

    Computer systems: A Programmer’s Perspective explains the underlying elements common among all computer systems and how they affect general application performance. Written from the programmer’s perspective, this book strives to teach readers how understanding basic elements of computer systems and executing real practice can lead them to create better programs. Spanning across computer science themes such as hardware architecture, the operating system, and systems software, the Third Edition serves as a comprehensive introduction to programming. This book strives to create programmers who understand all elements of computer systems and will be able to engage in any application of the field--from fixing faulty software, to writing more capable programs, to avoiding common flaws. It lays the groundwork for readers to delve into more intensive topics such as computer architecture, embedded systems, and cybersecurity. This book focuses on systems that execute an x86-64 machine code, and recommends th...

  9. Software graphs and programmer awareness

    CERN Document Server

    Baxter, G J

    2008-01-01

    Dependencies between types in object-oriented software can be viewed as directed graphs, with types as nodes and dependencies as edges. The in-degree and out-degree distributions of such graphs have quite different forms, with the former resembling a power-law distribution and the latter an exponential distribution. This effect appears to be independent of application or type relationship. A simple generative model is proposed to explore the proposition that the difference arises because the programmer is aware of the out-degree of a type but not of its in-degree. The model reproduces the two distributions, and compares reasonably well to those observed in 14 different type relationships across 12 different Java applications.

  10. Reliability evaluation programmable logic devices

    International Nuclear Information System (INIS)

    Programmable Logic Devices (PLD) are widely used as basic building modules in high integrity systems, considering their robust features such as gate density, performance, speed etc. PLDs are used to implement digital design such as bus interface logic, control logic, sequencing logic, glue logic etc. Due to semiconductor evolution, new PLDs with state-of-the-art features are arriving to the market. Since these devices are reliable as per the manufacturer's specification, they were used in the design of safety systems. But due to their reduced market life, the availability of performance data is limited. So evaluating the PLD before deploying in a safety system is very important. This paper presents a survey on the use of PLDs in the nuclear domain and the steps involved in the evaluation of PLD using Quantitative Accelerated Life Testing. (author)

  11. DNA-programmable nanoparticle crystallization

    Science.gov (United States)

    Park, Sung Yong; Lytton-Jean, Abigail K. R.; Lee, Byeongdu; Weigand, Steven; Schatz, George C.; Mirkin, Chad A.

    2008-01-01

    It was first shown more than ten years ago that DNA oligonucleotides can be attached to gold nanoparticles rationally to direct the formation of larger assemblies. Since then, oligonucleotide-functionalized nanoparticles have been developed into powerful diagnostic tools for nucleic acids and proteins, and into intracellular probes and gene regulators. In contrast, the conceptually simple yet powerful idea that functionalized nanoparticles might serve as basic building blocks that can be rationally assembled through programmable base-pairing interactions into highly ordered macroscopic materials remains poorly developed. So far, the approach has mainly resulted in polymerization, with modest control over the placement of, the periodicity in, and the distance between particles within the assembled material. That is, most of the materials obtained thus far are best classified as amorphous polymers, although a few examples of colloidal crystal formation exist. Here, we demonstrate that DNA can be used to control the crystallization of nanoparticle-oligonucleotide conjugates to the extent that different DNA sequences guide the assembly of the same type of inorganic nanoparticle into different crystalline states. We show that the choice of DNA sequences attached to the nanoparticle building blocks, the DNA linking molecules and the absence or presence of a non-bonding single-base flexor can be adjusted so that gold nanoparticles assemble into micrometre-sized face-centred-cubic or body-centred-cubic crystal structures. Our findings thus clearly demonstrate that synthetically programmable colloidal crystallization is possible, and that a single-component system can be directed to form different structures.

  12. Optical measurement of acoustic radiation pressure of the near-field acoustic levitation through transparent object

    CERN Document Server

    Nakamura, Satoshi; Sasao, Yasuhiro; Katsura, Kogure; Naoki, Kondo

    2013-01-01

    It is known that macroscopic objects can be levitated for few to several hundred micrometers by near-field acoustic field and this phenomenon is called near-field acoustic levitation (NFAL). Although there are various experiments conducted to measure integrated acoustic pressure on the object surface, up to now there was no direct method to measure pressure distribution. In this study we measured the acoustic radiation pressure of the near-field acoustic levitation via pressure-sensitive paint.

  13. Overmathematisation in game theory : pitting the Nash Equilibrium Refinement Programme against the Epistemic Programme

    NARCIS (Netherlands)

    de Bruin, Boudewijn

    2009-01-01

    The paper argues that the Nash Equilibrium Refinement Programme was less successful than its competitor, the Epistemic Programme (Interactive Epistemology). The prime criterion of success is the extent to which the programmes were able to reach the key objective guiding non-cooperative game theory f

  14. The KMSF laser fusion programme

    International Nuclear Information System (INIS)

    Laser-driven implosion experiments have been performed at both 1.06μm and 0.53μm. The fractional absorption was greater at 0.53μm although with the laser power available at 0.53μm it was not possible to observe effects of a high-temperature corona. Other experiments were performed using cryogenic targets at 1.06μm. It was found that the neutron yield and peak fuel densities were greater when the fuel formed a liquid or solid layer on the inside of the spherical glass-shell targets. (author)

  15. EMSP Final Report: Electrically Driven Technologies for Radioactive Aerosol Abatement

    Energy Technology Data Exchange (ETDEWEB)

    DePaoli, D.W.

    2003-01-22

    The purpose of this research project was to develop an improved understanding of how electrically driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume. There was anecdotal evidence in the literature that acoustic agglomeration and electrical coalescence could be used together to change the size distribution of aerosol particles in such a way as to promote easier filtration and less frequent maintenance of filtration systems. As such, those electrically driven technologies could potentially be used as remote technologies for improved treatment; however, existing theoretical models are not suitable for prediction and design. To investigate the physics of such systems, and also to prototype a system for such processes, a collaborative project was undertaken between Oak Ridge National Laboratory (ORNL) and the University of Texas at Austin (UT). ORNL was responsible for the larger-scale prototyping portion of the project, while UT was primarily responsible for the detailed physics in smaller scale unit reactors. It was found that both electrical coalescence and acoustic agglomeration do in fact increase the rate of aggregation of aerosols. Electrical coalescence requires significantly less input power than acoustic agglomeration, but it is much less effective in its ability to aggregate/coalesce aerosols. The larger-scale prototype showed qualitatively similar results as the unit reactor tests, but presented more difficulty in interpretation of the results because of the complex multi-physics coupling that necessarily occur in all larger

  16. Dynamic behavior of microscale particles controlled by standing bulk acoustic waves

    International Nuclear Information System (INIS)

    We analyze the dynamic behavior of a spherical microparticle submerged in a fluid medium, driven to the node of a standing bulk acoustic wave created by two opposing transducers. We derive the dynamics of the fluid-particle system taking into account the acoustic radiation force and the time-dependent and time-independent drag force acting on the particle. Using this dynamic model, we characterize the transient and steady-state behavior of the fluid-particle system as a function of the particle and fluid properties and the transducer operating parameters. The results show that the settling time and percent overshoot of the particle trajectory are dependent on the ratio of the acoustic radiation force and time-independent damping force. In addition, we show that the particle oscillates around the node of the standing wave with an amplitude that depends on the ratio of the time-dependent drag forces and the particle inertia.

  17. Management of Industrial Processes with Programmable Logic Controller

    Directory of Open Access Journals (Sweden)

    Marius Tufoi

    2009-10-01

    Full Text Available In a modern economy, automation (the control is primarily to raise the competitiveness of a product, either directly through price or quality, or indirectly through the improvement of working conditions of staff productive. The control of industrial processes involves the management of dynamic systems that have continuous states. These systems are described by differential equations and, in general, analog inputs and outputs. Management of these systems is achieved, in general, with classical automation, by automation or with analog computers which contains modules with input / output analog performance. If states, inputs and outputs of a system can be modeled using binary variables, then these systems can be driven with Programmable Logic Controller.

  18. Solution driven versus problem driven design: strategies and outcomes

    OpenAIRE

    Kruger, Corinne; Cross, Nigel

    2006-01-01

    Data from protocol studies of nine experienced industrial designers, performing the same task, were analysed to develop an expertise model of the product design process. The protocol data and the expertise model were used to identify four different cognitive strategies employed by the designers: problem driven, solution driven, information driven, and knowledge driven design strategies. These strategies were then related to task outcomes such as solution quality and creativity, and to process...

  19. Acoustics SIMOPS: managing the unnecessary

    Energy Technology Data Exchange (ETDEWEB)

    Hanton, Samuel John [Nautronix Marine Technology Solutions, Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Time is money, and offshore operations are expensive. The desire therefore, is to increase efficiency through the condensing of schedules. This inevitably leads to SIMOPS of some degree, and this paper discusses SIMOPS along with, more specifically, the challenges they provide to acoustic positioning. (author)

  20. Topology optimization for acoustic problems

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard

    2006-01-01

    In this paper a method to control acoustic properties in a room with topology optimization is presented. It is shown how the squared sound pressure amplitude in a certain part of a room can be minimized by distribution of material in a design domain along the ceiling in 2D and 3D. Nice 0-1 designs...

  1. Acoustics in the Martian Atmosphere

    Science.gov (United States)

    Williams, J.-P.

    2000-10-01

    With the advent of the first attempt to deliver an acoustic microphone to the Martian surface aboard the failed Mars Polar Lander, there has been growing interests in the development of acoustic sensors to compliment scientific payloads on future spacecraft. Terrestrial scientist have been very successful in using infrasound (sound at frequencies below human detection, detect and monitor atmospheric phenomena related to weather, tornadoes, mountain waves, microbaroms, ionospheric and auroral disturbances, and meteror/fireballs, as well as anthropogenic sources such as aircraft and nuclear explosions. Sounds on Mars at the audible frequencies (20 Hz to 20 kHz) will be severely attenuated due to viscous relaxation and thermal diffusion (collectively referred to as classical attenuation) which will be much more severe in the colder, less dense Martian atmosphere. Molecular relaxation of carbon dioxide will also contribute to the sound absorption in the lower audible frequencies. Since classical attenuation increases as a function of the frequency squared, at low infrasonic frequencies ( < 10 Hz), classical attenuation becomes less significant and sound absorption in the Martian atmosphere becomes more similar to that of the terrestrial atmosphere for the same frequencies. At these longer wavelengths, geometric spreading will dominate as the source of attenuation as the acoustic energy is spread out over an ever increasing spherical wave front. This implies that infrasound (10 to 0.01 Hz) will be a useful frequency range for future acoustic sensors developed for scientific payloads delivered to the Martian surface.

  2. Longitudinal bulk acoustic mass sensor

    DEFF Research Database (Denmark)

    Hales, Jan Harry; Teva, Jordi; Boisen, Anja;

    2009-01-01

    A polycrystalline silicon longitudinal bulk acoustic cantilever is fabricated and operated in air at 51 MHz. A mass sensitivity of 100 Hz/fg (1 fg=10(-15) g) is obtained from the preliminary experiments where a minute mass is deposited on the device by means of focused ion beam. The total noise i...

  3. Satellite and acoustic tracking device

    KAUST Repository

    Berumen, Michael L.

    2014-02-20

    The present invention relates a method and device for tracking movements of marine animals or objects in large bodies of water and across significant distances. The method and device can track an acoustic transmitter attached to an animal or object beneath the ocean surface by employing an unmanned surface vessel equipped with a hydrophone array and GPS receiver.

  4. SES and Acoustics at GSFC

    Science.gov (United States)

    Hogue, Patrick

    2008-01-01

    This paper presents air and surface cleanliness characterization of the acoustics test facility and large (SES) thermal vacuum chamber at Goddard Space flight Center in Greenbelt, MD during the New Horizons Pluto probe program. It is shown that slow back-fill of the SES chamber is necessary to prevent excessive particle redistribution.

  5. Acoustic counter-sniper system

    Science.gov (United States)

    Duckworth, Gregory L.; Gilbert, Douglas C.; Barger, James E.

    1997-02-01

    BBN has developed, tested, and fielded pre-production versions of a versatile acoustics-based counter-sniper system. This system was developed by BBN for the DARPA Tactical Technology Office to provide a low cost and accurate sniper detection and localization system. The system uses observations of the shock wave from supersonic bullets to estimate the bullet trajectory, Mach number, and caliber. If muzzle blast observations are also available from unsilenced weapons, the exact sniper location along the trajectory is also estimated. A newly developed and very accurate model of the bullet ballistics and acoustic radiation is used which includes bullet deceleration. This allows the use of very flexible acoustic sensor types and placements, since the system can model the bullet's flight, and hence the acoustic observations, over a wide area very accurately. System sensor configurations can be as simple as two small four element tetrahedral microphone arrays on either side of the area to be protected, or six omnidirectional microphones spread over the area to be monitored. Increased performance can be obtained by expanding the sensor field in size or density, and the system software is easily reconfigured to accommodate this at deployment time. Sensor nodes can be added using wireless network telemetry or hardwired cables to the command node processing and display computer. The system has been field tested in three government sponsored tests in both rural and simulated urban environments at the Camp Pendleton MOUT facility. Performance was characterized during these tests for various shot geometries and bullet speeds and calibers.

  6. User's manual for the REDIFFUSION programme

    International Nuclear Information System (INIS)

    REDIFFUSION is a programme developed for use in shield design. It carries out calculations of neutron and gamma-ray penetration in one-dimensional geometries using methods based on diffusion theory which provide approximate but rapid solutions. A description of the capabilities of the programme is given together with instructions for its use. (author)

  7. Teaching design engineering in an interdisciplinary programme

    NARCIS (Netherlands)

    Wits, Wessel; Homminga, Jasper; Endedijk, Maaike; Visscher, Klaasjan; Krab-Hüsken, Leonie; Berg, van den Frank; Wilhelm, Pascal

    2014-01-01

    ATLAS, the Academy of Technology and Liberal Arts & Sciences, is an interdisciplinary three-year Bachelor of Science honours programme for talented students that opened its doors in September 2013. This international programme uses the concept of project-led education to teach students to integrate

  8. Environmental Assessment of R&D Programmes

    DEFF Research Database (Denmark)

    Lyhne, Ivar; Byriel, Inger Pihl

    2013-01-01

    Despite their important role in shaping the technologies of the future, public research and development (R&D) programmes are rarely based on systematic assessments of the environmental effects. R&D programmes thus allocate a huge amount of financial resources to projects, which potentially may...

  9. Three years of an intensive Programme

    DEFF Research Database (Denmark)

    Pedersen, Jens Myrup; Lopez, Jose Manuel Guterrez Lopez; Kirikova, Marite;

    2015-01-01

    This paper summarizes valuable experiences and learning points from three years of the Erasmus funded Intensive Programme on “Implementing Europe’s Future Broadband Infrastructure”. The programme consisted of a course held each year 2012-2014 during two weeks of July, where 30-35 students and 10-...

  10. Sonic ingredients in television food programmes

    Directory of Open Access Journals (Sweden)

    Charlotte Rørdam Larsen

    2013-12-01

    Full Text Available The main focus of this article is the use, significance, and role of sound in food and food travel programmes, exemplified by cooking programmes broadcast on Danish television – public service and commercial channels. The aim is to demonstrate how sound and music in this kind of programme plays an important part mediating both the cooking and the kitchen as wellordered and well organized. The use of music represents flow, but refers also to locality, globality and identity, and is often linked to the notions of nostalgia, tradition and authenticity, and contributes to an aesthetization of food programmes as it forms part of the performance and presentation of meals. The early kitchen programmes emphasized on information, as a kind of living cooking books as the idea was to enlighten the housewives and their practices by challenging their common sense choices introducing a more French inspired kitchen. In relation to such kitchen programmes todays cooking programmes seem to appeal to a broader sensibility as they present us to the possibilities of modern life, and the chefs’ multisensuorious performances underlines this – often induced by the sound. It is through the sounds in food programmes that an authentic experience of taste and smell is mediated to the viewer: both through the lustful, approving sounds made by presenters and through the cooks’ handling of raw materials. What looks delicious, also smells and tastes delicious – mediated through sound.

  11. Programmable logic devices in experimental quantum optics

    OpenAIRE

    Stockton, J.; Armen, M.; Mabuchi, H.

    2002-01-01

    We discuss the unique capabilities of programmable logic devices (PLD's) for experimental quantum optics and describe basic procedures of design and implementation. Examples of advanced applications include optical metrology and feedback control of quantum dynamical systems. As a tutorial illustration of the PLD implementation process, a field programmable gate array (FPGA) controller is used to stabilize the output of a Fabry-Perot cavity.

  12. Programmable Logic Devices in Experimental Quantum Optics

    CERN Document Server

    Stockton, J K; Mabuchi, H

    2002-01-01

    We discuss the unique capabilities of programmable logic devices (PLD's) for experimental quantum optics and describe basic procedures of design and implementation. Examples of advanced applications include optical metrology and feedback control of quantum dynamical systems. As a tutorial illustration of the PLD implementation process, a field programmable gate array (FPGA) controller is used to stabilize the output of a Fabry-Perot cavity.

  13. 4th Pacific Rim Underwater Acoustics Conference

    CERN Document Server

    Xu, Wen; Cheng, Qianliu; Zhao, Hangfang

    2016-01-01

    These proceedings are a collection of 16 selected scientific papers and reviews by distinguished international experts that were presented at the 4th Pacific Rim Underwater Acoustics Conference (PRUAC), held in Hangzhou, China in October 2013. The topics discussed at the conference include internal wave observation and prediction; environmental uncertainty and coupling to sound propagation; environmental noise and ocean dynamics; dynamic modeling in acoustic fields; acoustic tomography and ocean parameter estimation; time reversal and matched field processing; underwater acoustic localization and communication as well as measurement instrumentations and platforms. These proceedings provide insights into the latest developments in underwater acoustics, promoting the exchange of ideas for the benefit of future research.

  14. Aerosol behaviour in an acoustic field

    International Nuclear Information System (INIS)

    The average size of an aerosol submitted to acoustic waves is increased. This results from coagulation of the finest particles on the largest ones. The mechanisms responsible for acoustic agglomeration are mentioned. An experimental apparatus was developed in order to control the evolution of aerosol distribution in an acoustic field. Important deposition on the walls of the agglomeration chamber was observed as a consequence of the acoustically induced turbulent flow. Finally, a dimensionless relationship was established between deposition rates and particle diameters as a function of experimental parameters (aeraulic and acoustic conditions, etc...)

  15. Determining Equilibrium Position For Acoustical Levitation

    Science.gov (United States)

    Barmatz, M. B.; Aveni, G.; Putterman, S.; Rudnick, J.

    1989-01-01

    Equilibrium position and orientation of acoustically-levitated weightless object determined by calibration technique on Earth. From calibration data, possible to calculate equilibrium position and orientation in presence of Earth gravitation. Sample not levitated acoustically during calibration. Technique relies on Boltzmann-Ehrenfest adiabatic-invariance principle. One converts resonant-frequency-shift data into data on normalized acoustical potential energy. Minimum of energy occurs at equilibrium point. From gradients of acoustical potential energy, one calculates acoustical restoring force or torque on objects as function of deviation from equilibrium position or orientation.

  16. Theoretical Estimation of the Acoustic Energy Generation and Absorption Caused by Jet Oscillation

    Science.gov (United States)

    Takahashi, Kin'ya; Iwagami, Sho; Kobayashi, Taizo; Takami, Toshiya

    2016-04-01

    We investigate the energy transfer between the fluid field and acoustic field caused by a jet driven by an acoustic particle velocity field across it, which is the key to understanding the aerodynamic sound generation of flue instruments, such as the recorder, flute, and organ pipe. Howe's energy corollary allows us to estimate the energy transfer between these two fields. For simplicity, we consider the situation such that a free jet is driven by a uniform acoustic particle velocity field across it. We improve the semi-empirical model of the oscillating jet, i.e., exponentially growing jet model, which has been studied in the field of musical acoustics, and introduce a polynomially growing jet model so as to apply Howe's formula to it. It is found that the relative phase between the acoustic oscillation and jet oscillation, which changes with the distance from the flue exit, determines the quantity of the energy transfer between the two fields. The acoustic energy is mainly generated in the downstream area, but it is consumed in the upstream area near the flue exit in driving the jet. This theoretical examination well explains the numerical calculation of Howe's formula for the two-dimensional flue instrument model in our previous work [ext-link ext-link-type="uri" xlink:href="http://doi.org/10.1088/0169-5983/46/6/061411" xlink:type="simple">Fluid Dyn. Res. 46, 061411 (2014)ext-link>] as well as the experimental result of Yoshikawa et al. [ext-link ext-link-type="uri" xlink:href="http://doi.org/10.1016/j.jsv.2012.01.026" xlink:type="simple">J. Sound Vib. 331, 2558 (2012)ext-link>].

  17. Education, Training and the Euratom Framework Programme

    International Nuclear Information System (INIS)

    The maintaining of knowledge implies education and training programmes that ensure not only the instruction of students and trainees but also the transfer of knowledge across generations. This is especially important for research in the Euratom field in the present context of nuclear renaissance. DG-Research is responsible for the implementation of the Euratom Framework Programme on nuclear research and training. Through these activities, it is striving to promote the integration of national radiation protection research programmes in Europe, including education and training in radiation protection. These education and training activities supported in the Euratom Programme are helping to establish top-quality teaching modules assembled into masters programmes or higher-level training packages jointly qualified and mutually recognised across the EU. This Euratom approach is entirely in line with the Bologna process. This paper presents and discusses the various actions in education and training in radiation protection supported by DG- Research. (authors)

  18. Patient Experiences of Structured Heart Failure Programmes

    Directory of Open Access Journals (Sweden)

    Nuala E. Tully

    2010-01-01

    Full Text Available Objectives. Patient experiences of structured heart failure rehabilitation and their views on the important components of heart failure services were examined. Methods. Focus groups were conducted with fifteen participants (men, =12 attending one of two heart failure rehabilitation programmes. Sessions were guided by a semistructured interview schedule covering participants' experiences of the programme, maintenance, and GP role. Focus group transcripts were analysed qualitatively. Results. Participants indicated that rehabilitation programmes substantially met their needs. Supervised exercise sessions increased confidence to resume physical activity, while peer-group interaction and supportive medical staff improved morale. However, once the programme ended, some participants' self-care motivation lapsed, especially maintenance of an exercise routine. Patients doubted their GPs' ability to help them manage their condition. Conclusion. Structured rehabilitation programmes are effective in enabling patients to develop lifestyle skills to live with heart failure. However, postrehabilitation maintenance interventions are necessary to sustain patients' confidence in disease self-management.

  19. Programmer`s manual for CAMCON: Compliance Assessment Methodology CONtroller

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [Sandia National Labs., Albuquerque, NM (United States); Gilkey, A.P.; Rudeen, D.K.; Byle, K.A. [New Mexico Engineering Research Inst., Albuquerque, NM (United States); Iuzzolino, H.J. [Geo-Centers, Inc., Albuquerque, NM (United States)

    1993-05-01

    CAMCON, the Compliance Assessment Methodology CONtroller, is an analysis system that assists in assessing the compliance of the Waste Isolation Pilot Plant (WIPP) with applicable long-term regulations of the US Environmental Protection Agency, including Subpart B of the Environmental Standards for the Management and Disposal of spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191 and 40CFR268.6, which is the portion of the Land Disposal Restrictions implementing the Resource, Conservative, and Recovery Act of 1976, as amended that states the conditions for disposal of hazardous chemical wastes. This manual provides an architectural overview of the CAMCON system. Furthermore this manual presents guidelines and presents suggestions for programmers developing the many different types of software necessary to investigate various events and physical processes of the WIPP. These guidelines include user interface requirements, minimum quality assurance requirements, coding style suggestions, and the use of numerous software libraries developed specifically for or adapted for the CAMCON system.

  20. Building Digital Economy - The Research Councils Programme and the Vision

    Science.gov (United States)

    Hand, John

    We at the Research Councils believe that there are many aspects of society and business that could be transformed by the innovative design and use of digital technologies. This has led to the Digital Economy Programme. The Digital Economy is an RCUK Cross-Research Council Programme, led by the EPSRC, but working closely with ESRC, MRC, AHRC and TSB. What is Digital Economy? Digital Economy is the novel design or use of information and communication technology to help transform the lives of individuals, society or business. All Digital Economy research involves the user community. This can include industry, government, society, charities or other groups as applicable. The research will understand the technologies and also why change is needed, what the impacts will be and who will benefit. Research in this cross-research council area can be driven by economic, social or technical need. The early involvement of the user community is vital if new technologies are to be integrated successfully into business opportunities, technical solutions or commercial products and processes. Challenges in the Digital Economy will require multi-disciplinary academic input, including, but not limited to, the arts and humanities, economic and social sciences and medical sciences, in addition to engineering and physical sciences.