WorldWideScience

Sample records for biological oceanography acoustic

  1. Biological Oceanography

    Science.gov (United States)

    Dyhrman, Sonya

    2004-10-01

    The ocean is arguably the largest habitat on the planet, and it houses an astounding array of life, from microbes to whales. As a testament to this diversity and its importance, the discipline of biological oceanography spans studies of all levels of biological organization, from that of single genes, to organisms, to their population dynamics. Biological oceanography also includes studies on how organisms interact with, and contribute to, essential global processes. Students of biological oceanography are often as comfortable looking at satellite images as they are electron micrographs. This diversity of perspective begins the textbook Biological Oceanography, with cover graphics including a Coastal Zone Color Scanner image representing chlorophyll concentration, an electron micrograph of a dinoflagellate, and a photograph of a copepod. These images instantly capture the reader's attention and illustrate some of the different scales on which budding oceanographers are required to think. Having taught a core graduate course in biological oceanography for many years, Charlie Miller has used his lecture notes as the genesis for this book. The text covers the subject of biological oceanography in a manner that is targeted to introductory graduate students, but it would also be appropriate for advanced undergraduates.

  2. Tsunami 2004 and the biological oceanography of Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Stephen, R.; Jayalakshmi, K.J.; Rahman, H.; Karuppasamy, P.K.; Nair, K.K.C.

    /plain; charset=ISO-8859-1 TSUNAMI 2004 AND THE BIOLOGICAL OCEANOGRAPHY OF BAY OF BENGAL ROSAMMA STEPHEN, K.J. JAYALAKSHMI, HABEEB RAHMAN, P.K. KARUPPUSWAMY and K.K.C. NAIR National Institute of Oceanography, Regional Centre, P.B.1913, Dr. Salim Ali Road...

  3. Cumulative and Synergistic Effects of Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use Physical Oceanography Component: Soundscapes Under Sea Ice: Can We Listen for Open Water?

    Science.gov (United States)

    2013-09-30

    open water? Jeffrey A Nystuen Applied Physics Laboratory University of Washington 1013 NE 40th Street Seattle, Washington 98105 phone: 206... Laboratory ,1013 NE 40th St,Seattle,WA,98105 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR...Listening to Glaciers: Passive Hydroacoustics Near Marine-Terminating Glaciers”, Oceanography, vol. 25. Stabeno, P.J, Falry, E.V., Kachel, N.B

  4. Biological oceanography of the red oceanic system

    Science.gov (United States)

    Theil, Hjalmar; Weikert, Horst

    1. In 1977, 1979 and 1980-81, investigations were carried out which aimed at evaluating the potential risks from mining metalliferous muds precipating in the Atlantis II Deep of the central Red Sea. This environmental research was initiated by the Saudi Sudanese Red Sea Joint Commission in order to avoid any danger for the Red Sea ecosystem. The broad environmental research programme coherent studies in physical, chemical, biological, and geological oceanography as well as toxicological investigations in the oceanic and in reef zones. We summarise the results from our biological fiels studies in the open sea. 2. The biological investigations were concentrated on the area of the Atlantis II Deep. Benthos was sampled between 700-2000m. For comparison a few samples were also taken further north in the central Red Sea, and to east and west along the flanking deep terraces (500-1000m). Plankton studies covered the total water column above the Deep, and were extended along the axial through to north and south. 3. Benthos sampling was carried out using a heavy closing trawl, a large box grab (box size 50 × 50 cm), Van Veen grabs and traps; photographic surveys were made a phototrap and a photosled. Community respiration was measured with a ship-board method using grab subsamples. Nutrient concentrations, seston and phytoplankton standing stocks as well as in situ primary production were determined from hydrocast samples. Data on zooplankton and micronekton composition and standing stock were obtained from samples collected using different multiple opening-and-closing nets equipped with 100 μm, 300 μm, and 1000 μm mesh sizes. Daily and ontogenetical vertical migration patterns were studied by comparisons of data from midday and midnight tows. 4. Throughout the whole area the sediment is a pteropod ooze containing low contentrations of organic matter; measured organic carbon and nitrogen contents were 0.5 and 0.05% respectively, and chloroplastic pigment equivalents

  5. Synthetic modelling of acoustical propagation applied to seismic oceanography experiments

    Science.gov (United States)

    Kormann, Jean; Cobo, Pedro; Biescas, Berta; Sallarés, Valentí; Papenberg, Cord; Recuero, Manuel; Carbonell, Ramón

    2010-03-01

    Recent work shows that multichannel seismic (MCS) systems provide detailed information on the oceans' finestructure. The aim of this paper is to analyze if high order numerical algorithms are suitable to accurately model the extremely weak wavefield scattered by the oceans' finestructures. For this purpose, we generate synthetic shot records along a coincident seismic and oceanographic profile acquired across a Mediterranean salt lens in the Gulf of Cadiz. We apply a 2D finite-difference time-domain propagation model, together with second-order Complex Frequency Shifted Perfectly Matched Layers at the numerical boundaries, using as reference a realistic sound speed map with the lateral resolution of the seismic data. We show that our numerical propagator creates an acoustical image of the ocean finestructures including the salt lens that reproduces with outstanding detail the real acquired one.

  6. Chemical oceanography

    National Research Council Canada - National Science Library

    Millero, F.J

    1996-01-01

    Chemical Oceanography presents a comprehensive examination of the chemistry of oceans through discussions of such topics as descriptive physical oceanography, the composition of seawater and the major...

  7. Making Data Available via the Biological and Chemical Oceanography Data Management Office - Implementation Details

    Science.gov (United States)

    Allison, M. D.; Groman, R. C.; Chandler, C. L.; Glover, D. M.; Wiebe, P. H.

    2008-12-01

    The Biological and Chemical Oceanography Data Management Office (BCO-DMO) was created from the U.S. Joint Global Ocean Flux Study (U.S. JGOFS) and the U.S. GLOBal ocean ECosystems dynamics (U.S. GLOBEC) Data Management Offices. The BCO-DMO is a NSF funded project that provides support for scientists funded by either the NSF's Biological or Chemical Oceanography Program Office to facilitate making their projects' data publically accessible. To extend the domains of the U.S. JGOFS and U.S. GLOBEC programs and to enable new capabilities, the BCO-DMO formalized our metadata collection efforts and designed and created the BCO-DMO metadata database. This database, together with our new website content (http://www.bco-dmo.org) and a geospatial interface based on the University of Minnesota's MapServer software, currently provide access to information and data from nine science programs and their associated 27 projects. This poster highlights some of the details of our system's design decisions that support the data discoverability, access, display, download and interoperability features, and capabilities of the BCO-DMO data interface. Initial efforts to use existing metadata schemas were unsuccessful as they did not address our specific needs or were overly generalized and therefore more complicated than necessary. The database design has evolved over time as we have learned more about what information needs to be preserved to support multiple interfaces and to enable machine-to-machine interoperability. Our latest enhancements include database tables to store additional information about the field or variable names that further describe the experimental, at sea, and historical data in order to support our new geospatial interface. Other features will facilitate data interoperability, provide flexibility in supporting different input data formats, capture data provenance information and allow creation of metadata records that are in compliance with community adopted

  8. AFSC/RACE/EcoFOCI: 2010 Chukchi Acoustics, Oceanography, and Zooplankton (CHAOZ) Study - 1AE10

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data collected on this cruise included the following: acoustic recordings of marine species detected by sonobuoys; oceanographic measurements including water...

  9. The ecology of plankton in biological oceanography: a tribute to Marta Estrada’s task

    Directory of Open Access Journals (Sweden)

    Jordi Solé

    2016-09-01

    Full Text Available Plankton ecology has been the object of intense research and progress in the last few decades. This has been partly due to technological advances that have facilitated the multidisciplinary and high-resolution sampling of ecosystems and improved experimentation and analytical methodologies, and to sophisticated modelling. In addition, exceptional researchers have had the vision to integrate all these innovative tools to form a solid theoretical background in ecology. Here we provide an overview of the outstanding research work conducted by Professor Marta Estrada and her pioneering contribution to different areas of research in the last four decades. Her research in biological oceanography has mainly focussed on phytoplankton ecology, taxonomy and physiology, the functional structure of plankton communities, and physical and biological interactions in marine ecosystems. She has combined a variety of field and laboratory approaches and methodologies, from microscopy to satellite observations, including in-depth statistical data analysis and modelling. She has been a reference for scientists all over the world. Here, her contributions to plankton ecology are summarized by some of her students and closest collaborators, who had the privilege to share their science and everyday experiences with her.

  10. Physical oceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, C.S.; Murty, V.S.N.

    The chapter on physical oceanography of the Indian Ocean is written keeping in mind the graduate students and researchers. It starts with a brief introduction (citing latest expeditions) followed by the coastal and near processes (wave climate...

  11. Applications of 14C-AMS on archaeology, climate, environment, geology, oceanography and biology

    International Nuclear Information System (INIS)

    Gomes, P.R.S.; Anjos, R.M.; Macario, K.D.; Santos, G.M.

    2005-01-01

    The first experiment discusses the chronology of prehistoric settlements of the central-south Brazilian coast. In the southern Brazilian coast there is a high density of these shellmounds, dated in general between 6,000 and 2,000 BP. A charcoal sample from a coastal shellmound of Rio de Janeiro State was dated by 14 C-AMS to 7,860±80 years BP. This is an unexpected result that pulls back by some two thousand years the antiquity consensually accepted for the settlement of that region. We performed an experiment concerning the isotopic signature of the local waters of an important Brazilian coastal upwelling, located in Arraial do Cabo, R.J., with applications in the fields of Oceanography and Marine Ecology. We assess the contribution of the wind-driven coastal upwelling of Arraial do Cabo to the local biological production. The variation of the carbon isotopic compositions was investigated in a population of a seaweed. Upwelling events were simulated in the laboratory, in order to study three regimes: total upwelling (SACW), partial upwelling (mixed water) and no-upwelling (TW). Water samples were collected at 70 m depth (SACW) and at 10 m (TW). The seaweed was cultivated during seven days, in controlled conditions, into the three mentioned types of water. The results of 14 C-AMS measurements in the seaweed tissue show a clear indication of difference in the isotopic signature of the water sources, allowing to infer the differences of the water sources. We believe that the present results contribute to opening new perspectives for the use of 14 C as a tracer of the biological production in upwelling areas all over the world. The next reported experiment is on climate at the Amazon region. An increase in the Hg flux is a strong indicator of disturbance in a forest ecosystem related to abrupt changes in the water balance, and its changes reflect changes in the ocean and average regional temperatures. In regions where the geological background of mercury is

  12. Arctic data compilation and appraisal. Vol. 13, Northwest passage: biological oceanography-whales, 1920-1984

    Energy Technology Data Exchange (ETDEWEB)

    Norton, P.; de March, L.; Smiley, B.D.

    1987-01-01

    The pace of offshore development in the Canadian Arctic has emphasized the need to review the sufficiency and suitability of available scientific information for design, regulatory, and planning purposes. This report presents part of the results of the first stage of this review process, the compilation and appraisal of existing data sets on whales in the Northwest Passage. Measurements were made of narwhales, white whales, bowhead whales, and killer whales, and most commonly concern numbers, identification, movements, reproduction, food, and color. Overall, 143 data sets are inventoried for the period from 1820 to 1984. Times and locations of sampling efforts are listed in tables and are also shown on computer-drawn maps. Sampling methodology and intensity, whale measurements and observations obtained by species, and concurrent biological, physical, and chemical measurements are described in the tables. A 5-level rating system, based on sampling methodology, is outlined and has been applied to each measurement in each data set as a rough indication of data reliability. Data sets are indexed according to geographic coverage, study methods, species, specific measurements and observations made, and published references. The form, location, and availability of original data are provided if known. 415 figs., 3 tabs.

  13. Acoustic Droplet Vaporization in Biology and Medicine

    Directory of Open Access Journals (Sweden)

    Chung-Yin Lin

    2013-01-01

    Full Text Available This paper reviews the literature regarding the use of acoustic droplet vaporization (ADV in clinical applications of imaging, embolic therapy, and therapeutic delivery. ADV is a physical process in which the pressure waves of ultrasound induce a phase transition that causes superheated liquid nanodroplets to form gas bubbles. The bubbles provide ultrasonic imaging contrast and other functions. ADV of perfluoropentane was used extensively in imaging for preclinical trials in the 1990s, but its use declined rapidly with the advent of other imaging agents. In the last decade, ADV was proposed and explored for embolic occlusion therapy, drug delivery, aberration correction, and high intensity focused ultrasound (HIFU sensitization. Vessel occlusion via ADV has been explored in rodents and dogs and may be approaching clinical use. ADV for drug delivery is still in preclinical stages with initial applications to treat tumors in mice. Other techniques are still in preclinical studies but have potential for clinical use in specialty applications. Overall, ADV has a bright future in clinical application because the small size of nanodroplets greatly reduces the rate of clearance compared to larger contrast agent bubbles and yet provides the advantages of ultrasonographic contrast, acoustic cavitation, and nontoxicity of conventional perfluorocarbon contrast agent bubbles.

  14. Acoustic Volume Scattering: Its Dependence on Frequency and Biological Scatterers.

    Science.gov (United States)

    The report discusses the dependence of acoustic valume scattering on frequency and biological scatterers in the Westfall Seamount Area, 200 miles off... the coast of San Diego, California. Theoretical calculations and experimental data both showed a correlation between the frequency dependence of...scattering (from 1 to 20 kilohertz) and midwater gas-bladder fishes. It is the hypothesis of the report that the size limitation of the swimbladders

  15. Some biological aspects in acoustic contamination

    International Nuclear Information System (INIS)

    Palacio B, Jaime

    1996-01-01

    For an appropriate diagnosis of the environmental quality of the aquatic ecosystems, the aspects physic chemicals and biotic should be conjugated and to identify the processes of natural origin and anthropogenic. Any study based on a partial vision that excludes a holistic treatment of the problem, limits the possibilities of interpretation of the data and the quality of the results. The aquatic biota acts as a natural monitor, because it responds in an integral form to the changes under the environmental conditions. Among the procedures for investigation of the biological effects of the deterioration of the quality of the natural waters, the toxicity rehearsals have acquired a growing importance in the last years, like base for the formulation of permissible maximum concentrations. In the aquatic toxicology, the tests of sharp toxicity and chronicle are those most broadly diffused ones. One of the most frequent critics to the rehearsals of sharp toxicity is that the high concentrations of toxic substances employees lower laboratory conditions; they are not common in the natural atmospheres. Nevertheless, these tests allow to locate the main contamination sources and to apply factors for the estimate of levels of security. The approach more employee to evaluate the sharp toxic effects of a xeno-biotic, is the concentration lethal stocking (CL50) For the calculation of the CL50 it has intended several forms that include techniques graphic simple or computational model based on the use of transformations. The procedure more applied in Colombia for the computation of the CL50 is the graphic method of Litchfield - Wilcoxon (1949). Starting from statistical considerations the employment of graphic techniques is not recommended and model computational should only be used that allow the estimate of the intervals of trust of the CL50

  16. 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.

  17. Acoustic Effects Accurately Predict an Extreme Case of Biological Morphology

    Science.gov (United States)

    Zhang, Zhiwei; Truong, Son Nguyen; Müller, Rolf

    2009-07-01

    The biosonar system of bats utilizes physical baffle shapes around the sites of ultrasound emission for diffraction-based beam forming. Among these shapes, some extreme cases have evolved that include a long noseleaf protrusion (sella) in a species of horseshoe bat. We have evaluated the acoustic cost function associated with sella length with a computational physics approach and found that the extreme length can be predicted accurately from a fiducial point on this function. This suggests that some extreme cases of biological morphology can be explained from their physical function alone.

  18. NODC Standard Product: Climatic atlas of the Arctic Seas 2004 - Database of the Barents, Kara, Laptev, and White Seas - Oceanography and marine biology (NODC Accession 0098061)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Atlas presents primary data on meteorology, oceanography, and hydrobiology from the Barents, Kara, Laptev, and White Seas, which were collected during the...

  19. Introduction to fisheries oceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Sumitra-Vijayaraghavan

    Fisheries oceanography can be applied to fisheries ecology, fisheries management and practical fishing. Physico-chemical parameters of the environment (temperature, currents, waves, light, oxygen and salinity) have profound effect on fish...

  20. Mass spectrometry in oceanography

    International Nuclear Information System (INIS)

    Aggarwal, Suresh K.

    2000-01-01

    Mass spectrometry plays an important role in oceanography for various applications. Different types of inorganic as well as organic mass spectrometric techniques are being exploited world-wide to understand the different aspects of marine science, for palaeogeography, palaeoclimatology and palaeoecology, for isotopic composition and concentrations of different elements as well as for speciation studies. The present paper reviews some of the applications of atomic mass spectrometric techniques in the area of oceanography

  1. Topography and biological noise determine acoustic detectability on coral reefs

    KAUST Repository

    Cagua, Edgar F.

    2013-08-19

    Acoustic telemetry is an increasingly common tool for studying the movement patterns, behavior and site fidelity of marine organisms, but to accurately interpret acoustic data, the variability, periodicity and range of detectability between acoustic tags and receivers must be understood. The relative and interactive effects of topography with biological and environmental noise have not been quantified on coral reefs. We conduct two long-term range tests (1- and 4-month duration) on two different reef types in the central Red Sea to determine the relative effect of distance, depth, topography, time of day, wind, lunar phase, sea surface temperature and thermocline on detection probability. Detectability, as expected, declines with increasing distance between tags and receivers, and we find average detection ranges of 530 and 120 m, using V16 and V13 tags, respectively, but the topography of the reef can significantly modify this relationship, reducing the range by ~70 %, even when tags and receivers are in line-of-sight. Analyses that assume a relationship between distance and detections must therefore be used with care. Nighttime detection range was consistently reduced in both locations, and detections varied by lunar phase in the 4-month test, suggesting a strong influence of biological noise (reducing detection probability up to 30 %), notably more influential than other environmental noises, including wind-driven noise, which is normally considered important in open-water environments. Analysis of detections should be corrected in consideration of the diel patterns we find, and range tests or sentinel tags should be used for more than 1 month to quantify potential changes due to lunar phase. Some studies assume that the most usual factor limiting detection range is weather-related noise; this cannot be extrapolated to coral reefs. © 2013 Springer-Verlag Berlin Heidelberg.

  2. Acoustic Moorings for Integrated Cetacean-Prey Studies

    Science.gov (United States)

    2015-09-30

    Chou E, Roch MA (in prep) Habitat use of calling blue and fin whales in Southern California Bight. Marine Ecology Progress Series. Wiggins SM...merging acoustics, biology, and oceanography to answering a suite of ecological questions. RELATED PROJECTS The proposed moorings will lead to...Johnson S, Kerosky S, Roche L, Solsona Berga A, Wakefield L, Wiggins SM (2012) Passive Acoustic Monitoring for Marine Mammals in the Gulf of Alaska

  3. Oceanography of the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, B.N.

    This volume is an outcome of the presentation of selected 74 papers at the International Symposium on the Oceanography of the Indian Ocean held at National Institute of Oceanography during January 1991. The unique physical setting of the northern...

  4. Basic concepts in oceanography

    International Nuclear Information System (INIS)

    Small, L.F.

    1997-01-01

    Basic concepts in oceanography include major wind patterns that drive ocean currents, and the effects that the earth's rotation, positions of land masses, and temperature and salinity have on oceanic circulation and hence global distribution of radioactivity. Special attention is given to coastal and near-coastal processes such as upwelling, tidal effects, and small-scale processes, as radionuclide distributions are currently most associated with coastal regions. (author)

  5. Biological data - Integrated acoustic and trawl survey of Pacific hake off the Pacific Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Integrated acoustic and trawl surveys are used to assess the distribution, biomass, and biology of Pacific hake along the Pacific coasts of the United States and...

  6. Connecting Oceanography and Music

    Science.gov (United States)

    Beauregard, J. L.

    2016-02-01

    Capturing and retaining the interest of non-science majors in science classes can be difficult, no matter what type of science. At Berklee College of Music, this challenge is especially significant, as all students are music majors. In my Introductory Oceanography course, I use a final project as a way for the students to link class material with their own interests. The students may choose any format to present their projects to the class; however, many students write and perform original music. The performances of ocean-themed music have become a huge draw of the Introductory Oceanography course. In an effort to expand the reach of this music, several colleagues and I organized the first Earth Day event at Berklee, `Earthapalooza 2015.' This event included performances of music originally written for the final projects, as well as other musical performances, poetry readings, guest talks, and information booths. Although the idea of an Earth Day event is not new, this event is unique in that student performances really resonate with the student audience. Additionally, since many of these students will enter professional careers in the performance and recording industries, the potential exists for them to expose large audiences to the issues of oceanography through music. In this presentation, I will play examples of original student compositions and show video of the live student performances. I will also discuss the benefits and challenges of the final projects and the Earth Day event. Finally, I will highlight the future plans to continue ocean-themed music at Berklee.

  7. Electrical circuit modeling and analysis of microwave acoustic interaction with biological tissues.

    Science.gov (United States)

    Gao, Fei; Zheng, Qian; Zheng, Yuanjin

    2014-05-01

    Numerical study of microwave imaging and microwave-induced thermoacoustic imaging utilizes finite difference time domain (FDTD) analysis for simulation of microwave and acoustic interaction with biological tissues, which is time consuming due to complex grid-segmentation and numerous calculations, not straightforward due to no analytical solution and physical explanation, and incompatible with hardware development requiring circuit simulator such as SPICE. In this paper, instead of conventional FDTD numerical simulation, an equivalent electrical circuit model is proposed to model the microwave acoustic interaction with biological tissues for fast simulation and quantitative analysis in both one and two dimensions (2D). The equivalent circuit of ideal point-like tissue for microwave-acoustic interaction is proposed including transmission line, voltage-controlled current source, envelop detector, and resistor-inductor-capacitor (RLC) network, to model the microwave scattering, thermal expansion, and acoustic generation. Based on which, two-port network of the point-like tissue is built and characterized using pseudo S-parameters and transducer gain. Two dimensional circuit network including acoustic scatterer and acoustic channel is also constructed to model the 2D spatial information and acoustic scattering effect in heterogeneous medium. Both FDTD simulation, circuit simulation, and experimental measurement are performed to compare the results in terms of time domain, frequency domain, and pseudo S-parameters characterization. 2D circuit network simulation is also performed under different scenarios including different sizes of tumors and the effect of acoustic scatterer. The proposed circuit model of microwave acoustic interaction with biological tissue could give good agreement with FDTD simulated and experimental measured results. The pseudo S-parameters and characteristic gain could globally evaluate the performance of tumor detection. The 2D circuit network

  8. West Hackberry Strategic Petroleum Reserve site brine disposal monitoring, Year I report. Volume V. Supporting data for estuarine hydrology, discharge plume analysis, chemical oceanography, biological oceanography, and data management. Final report

    Energy Technology Data Exchange (ETDEWEB)

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)

    1983-02-01

    This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which located in southwestern Louisiana, and which is designed to store 241 million barrels of crude oil. Oil storage caverns are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. Volume V contains appendices for the following: supporting data for estuarine hydrology and hydrography; supporting data analysis of discharge plume; supporting data for water and sediment chemistry; CTD/DO and pH profiles during biological monitoring; supporting data for nekton; and supporting data for data management.

  9. Factors influencing the evolution of acoustic communication: biological constraints.

    Science.gov (United States)

    Ryan, M J

    1986-01-01

    Numerous studies have investigated selective forces that appear to influence the evolution of acoustic communication systems. I review a number of constraints on evolution in these systems. A species' history is of undeniable importance in the analysis of any trait. However, studies have given little or no attention to phylogenetic patterns of acoustic signals. This precludes the identification of phylogenetic constraints, and should be viewed as a serious constraint on our ability to understand how communication systems evolve. Morphological constraints influence the energetic efficiency of acoustic communication. To maximize transmission distance of signals used in long-range communication, the animal's morphology favors signals with high frequencies. Thus morphology acts in opposition to properties of the environment, which favor low frequencies for use in long-range communication. Sensory receptors also play an important role in the evolution of acoustic signals. There is significant variation in the frequency range to which an inner-ear organ of the frog is sensitive. Different lineages of frogs are characterized by ear organs with different ranges of sensitivity. This variation should influence the frequency range over which calls evolved and, as a consequence, might have influenced the rate at which different lineages of anurans speciate.

  10. Seasonal oceanography from physics to micronekton in the south-west Pacific

    Science.gov (United States)

    Menkes, C. E.; Allain, V.; Rodier, M.; Gallois, F.; Lebourges-Dhaussy, A.; Hunt, B. P. V.; Smeti, H.; Pagano, M.; Josse, E.; Daroux, A.; Lehodey, P.; Senina, I.; Kestenare, E.; Lorrain, A.; Nicol, S.

    2015-03-01

    Tuna catches represent a major economic and food source in the Pacific Ocean, yet are highly variable. This variability in tuna catches remains poorly explained. The relationships between the distributions of tuna and their forage (micronekton) have been mostly derived from model estimates. Observations of micronekton and other mid-trophic level organisms, and their link to regional oceanography, however are scarce and constitute an important gap in our knowledge and understanding of the dynamics of pelagic ecosystems. To fill this gap, we conducted two multidisciplinary cruises (Nectalis1 and Nectalis2) in the New Caledonian Exclusive Economic Zone (EEZ) at the southeastern edge the Coral Sea, in 2011 to characterize the oceanography of the region during the cool (August) and the hot (December) seasons. The physical and biological environments were described by hydrology, nutrients and phytoplankton size structure and biomass. Zooplankton biomass was estimated from net sampling and acoustics and micronecton was estimated from net sampling, the SEAPODYM ecosystem model, a dedicated echosounder and non-dedicated acoustics. Results demonstrated that New Caledonia is located in an oligotrophic area characterized by low nutrient and low primary production which is dominated by a high percentage of picoplankton cyanobacteria Prochlorococcus (>90%). The area exhibits a large-scale north-south temperature and salinity gradient. The northern area is influenced by the equatorial Warm Pool and the South Pacific Convergence Zone and is characterized by higher temperature, lower salinity, lower primary production and micronekton biomass. The southern area is influenced by the Tasman Sea and is characterized by cooler temperature, higher salinity, higher primary production and micronekton biomass. The dynamic oceanography and the complex topography create a myriad of mesoscale features including eddies, inducing patchy structures in the ecosystem. During the cool season, a

  11. Acoustic and biological trends on coral reefs off Maui, Hawaii

    Science.gov (United States)

    Kaplan, Maxwell B.; Lammers, Marc O.; Zang, Eden; Aran Mooney, T.

    2018-03-01

    Coral reefs are characterized by high biodiversity, and evidence suggests that reef soundscapes reflect local species assemblages. To investigate how sounds produced on a given reef relate to abiotic and biotic parameters and how that relationship may change over time, an observational study was conducted between September 2014 and January 2016 at seven Hawaiian reefs that varied in coral cover, rugosity, and fish assemblages. The reefs were equipped with temperature loggers and acoustic recording devices that recorded on a 10% duty cycle. Benthic and fish visual survey data were collected four times over the course of the study. On average, reefs ranged from 0 to 80% live coral cover, although changes between surveys were noted, in particular during the major El Niño-related bleaching event of October 2015. Acoustic analyses focused on two frequency bands (50-1200 and 1.8-20.5 kHz) that corresponded to the dominant spectral features of the major sound-producing taxa on these reefs, fish, and snapping shrimp, respectively. In the low-frequency band, the presence of humpback whales (December-May) was a major contributor to sound level, whereas in the high-frequency band sound level closely tracked water temperature. On shorter timescales, the magnitude of the diel trend in sound production was greater than that of the lunar trend, but both varied in strength among reefs, which may reflect differences in the species assemblages present. Results indicated that the magnitude of the diel trend was related to fish densities at low frequencies and coral cover at high frequencies; however, the strength of these relationships varied by season. Thus, long-term acoustic recordings capture the substantial acoustic variability present in coral-reef ecosystems and provide insight into the presence and relative abundance of sound-producing organisms.

  12. Smart DNA Fabrication Using Sound Waves: Applying Acoustic Dispensing Technologies to Synthetic Biology.

    Science.gov (United States)

    Kanigowska, Paulina; Shen, Yue; Zheng, Yijing; Rosser, Susan; Cai, Yizhi

    2016-02-01

    Acoustic droplet ejection (ADE) technology uses focused acoustic energy to transfer nanoliter-scale liquid droplets with high precision and accuracy. This noncontact, tipless, low-volume dispensing technology minimizes the possibility of cross-contamination and potentially reduces the costs of reagents and consumables. To date, acoustic dispensers have mainly been used in screening libraries of compounds. In this paper, we describe the first application of this powerful technology to the rapidly developing field of synthetic biology, for DNA synthesis and assembly at the nanoliter scale using a Labcyte Echo 550 acoustic dispenser. We were able to successfully downscale PCRs and the popular one-pot DNA assembly methods, Golden Gate and Gibson assemblies, from the microliter to the nanoliter scale with high assembly efficiency, which effectively cut the reagent cost by 20- to 100-fold. We envision that acoustic dispensing will become an instrumental technology in synthetic biology, in particular in the era of DNA foundries. © 2015 Society for Laboratory Automation and Screening.

  13. Oceanography: The Past: Oceanography: The Present and Future

    Science.gov (United States)

    Gordon, Arnold L.

    Oceanography is a young science, close to its historical roots, but it's maturing fast as “state-of-the-art” technology and computer-aided numerical modeling play an increasing role. Our ability to obtain, process, and analyze enormous volumes of data would stun an oceanographer of the 1930's. (I hope he would be equally impressed by the quality of modern data.) The Third International Congress on the History of Oceanography and the celebration of the 50th anniversary of the Woods Hole Oceanographic Institution (WHOI) were both held in September 1980 at WHOI; and both events were taken as an opportunity to improve our understanding of the past and present of oceanography, and future of the ocean sciences with the thought that we could thereby better influence future trends.

  14. Acoustics

    Science.gov (United States)

    Goodman, Jerry R.; Grosveld, Ferdinand

    2007-01-01

    The acoustics environment in space operations is important to maintain at manageable levels so that the crewperson can remain safe, functional, effective, and reasonably comfortable. High acoustic levels can produce temporary or permanent hearing loss, or cause other physiological symptoms such as auditory pain, headaches, discomfort, strain in the vocal cords, or fatigue. Noise is defined as undesirable sound. Excessive noise may result in psychological effects such as irritability, inability to concentrate, decrease in productivity, annoyance, errors in judgment, and distraction. A noisy environment can also result in the inability to sleep, or sleep well. Elevated noise levels can affect the ability to communicate, understand what is being said, hear what is going on in the environment, degrade crew performance and operations, and create habitability concerns. Superfluous noise emissions can also create the inability to hear alarms or other important auditory cues such as an equipment malfunctioning. Recent space flight experience, evaluations of the requirements in crew habitable areas, and lessons learned (Goodman 2003; Allen and Goodman 2003; Pilkinton 2003; Grosveld et al. 2003) show the importance of maintaining an acceptable acoustics environment. This is best accomplished by having a high-quality set of limits/requirements early in the program, the "designing in" of acoustics in the development of hardware and systems, and by monitoring, testing and verifying the levels to ensure that they are acceptable.

  15. Authorized Course of Instruction for the Quinmester Program. Science: Introduction to Marine Science; Recreation and the Sea; Oceanography; Marine Ecology of South Florida, and Invertebrate Marine Biology.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    All five units, developed for the Dade County Florida Quinmester Program, included in this collection concern some aspect of marine studies. Except for "Recreation and the Sea," intended to give students basic seamanship skills and experience of other marine recreation, all units are designed for students with a background in biology or…

  16. West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume III. Biological oceanography: Chapter 9, zooplankton. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Turgeon, K.W.

    1983-02-01

    This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which is located in southwestern Louisiana and is designed to store 241 million barrels of crude oil. Oil shortage cavers are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. This volume contains chapter 9 on zooplankton.

  17. Biological oceanography, biogeochemical cycles, and pelagic ecosystem functioning of the east-central South Pacific Gyre: focus on Easter Island and Salas y Gómez Island

    OpenAIRE

    Von Dassow , Peter; Collado-Fabbri , Silvana

    2014-01-01

    International audience; The Exclusive Economic Zone of Chile defined by Easter Island and Salas y Gómez Island is in the South Pacific Subtropical Gyre (SPSG), putting it at the center of the most oligotrophic and biomass poor waters in the world. Only 10 biological oceanographic expeditions have entered this zone in 105 years (1905-2010). We review key aspects of the plankton ecosystem and biogeochemical function relevant for the understanding of and conservation planning for marine environm...

  18. Technological, biological, and acoustical constraints to music perception in cochlear implant users.

    Science.gov (United States)

    Limb, Charles J; Roy, Alexis T

    2014-02-01

    Despite advances in technology, the ability to perceive music remains limited for many cochlear implant users. This paper reviews the technological, biological, and acoustical constraints that make music an especially challenging stimulus for cochlear implant users, while highlighting recent research efforts to overcome these shortcomings. The limitations of cochlear implant devices, which have been optimized for speech comprehension, become evident when applied to music, particularly with regards to inadequate spectral, fine-temporal, and dynamic range representation. Beyond the impoverished information transmitted by the device itself, both peripheral and central auditory nervous system deficits are seen in the presence of sensorineural hearing loss, such as auditory nerve degeneration and abnormal auditory cortex activation. These technological and biological constraints to effective music perception are further compounded by the complexity of the acoustical features of music itself that require the perceptual integration of varying rhythmic, melodic, harmonic, and timbral elements of sound. Cochlear implant users not only have difficulty perceiving spectral components individually (leading to fundamental disruptions in perception of pitch, melody, and harmony) but also display deficits with higher perceptual integration tasks required for music perception, such as auditory stream segregation. Despite these current limitations, focused musical training programs, new assessment methods, and improvements in the representation and transmission of the complex acoustical features of music through technological innovation offer the potential for significant advancements in cochlear implant-mediated music perception. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Charney's Influence on Modern Oceanography

    Science.gov (United States)

    Cane, M. A.

    2017-12-01

    In this talk I will review some of Jule Charney's impacts on current oceanographic research. He was of course a major seminal figure in geophysical fluid dynamics, an approach to understanding the atmosphere and oceans that has been thoroughly absorbed in contemporary thinking. In oceanography, his publications make vorticity dynamics the centerpiece of his analysis. Here I pursue two other aspects of his work. The first is to note that his 1955 paper "The Gulf Stream as an inertial boundary layer" appears to be the earliest numerical model in oceanography. The second is that his work on the equatorial undercurrent leads to a simplification of equatorial ocean structure that was exploited by Zebiak and Cane in their model for ENSO, and thus structures later views of how equatorial ocean dynamics influence sea surface temperature.

  20. Biological oceanography, biogeochemical cycles, and pelagic ecosystem functioning of the east-central South Pacific Gyre: focus on Easter Island and Salas y Gómez Island

    Directory of Open Access Journals (Sweden)

    Peter von Dassow

    2014-10-01

    Full Text Available The Exclusive Economic Zone of Chile defined by Easter Island and Salas y Gómez Island is in the South Pacific Sub-tropical Gyre (SPSG, putting it at the center of the most oligotrophic and biomass poor waters in the world. Only 10 biological oceanographic expeditions have entered this zone in 105 years (19052010. We review key aspects of the plankton ecosystem and biogeochemical function relevant for the understanding of and conservation planning for marine environments. Plankton production is limited by lack of dissolved inorganic fixed nitrogen, not phosphorous. Higher organic nitrogen levels might be biologically unavailable. Short-term experiments suggested iron is not limiting, yet iron still likely limits nitrogen fixation, and thus production, at longer time scales, as the presence of nitrogen-fixers is exceptionally low compared to other ocean gyres. Plankton function is dominated by the smallest unicellular organisms, picoplankton (<3 μm in diameter. The SPSG represents a center of high biodiversity for picoplankton, as well as heterotrophic organisms such as tinntinids, siphonophores, and possibly amphipods, although data for key zooplankton, such as copepods, are lacking. Many groups exhibit negative relationships between diversity and total plankton biomass. High diversity might result from dispersal from a very large metacommunity and minimal competition within functional groups. Whether an island-mass effect causes a real or apparent increase in plankton biomass around Easter Island must be confirmed by high-resolution sampling in situ. Long-term threats to the planktonic ecosystem may include climate change-enhanced ocean stratification and plastic marine debris accumulation. Finally, priorities for future research are highlighted.

  1. Biologically relevant photoacoustic imaging phantoms with tunable optical and acoustic properties

    Science.gov (United States)

    Vogt, William C.; Jia, Congxian; Wear, Keith A.; Garra, Brian S.; Joshua Pfefer, T.

    2016-10-01

    Established medical imaging technologies such as magnetic resonance imaging and computed tomography rely on well-validated tissue-simulating phantoms for standardized testing of device image quality. The availability of high-quality phantoms for optical-acoustic diagnostics such as photoacoustic tomography (PAT) will facilitate standardization and clinical translation of these emerging approaches. Materials used in prior PAT phantoms do not provide a suitable combination of long-term stability and realistic acoustic and optical properties. Therefore, we have investigated the use of custom polyvinyl chloride plastisol (PVCP) formulations for imaging phantoms and identified a dual-plasticizer approach that provides biologically relevant ranges of relevant properties. Speed of sound and acoustic attenuation were determined over a frequency range of 4 to 9 MHz and optical absorption and scattering over a wavelength range of 400 to 1100 nm. We present characterization of several PVCP formulations, including one designed to mimic breast tissue. This material is used to construct a phantom comprised of an array of cylindrical, hemoglobin-filled inclusions for evaluation of penetration depth. Measurements with a custom near-infrared PAT imager provide quantitative and qualitative comparisons of phantom and tissue images. Results indicate that our PVCP material is uniquely suitable for PAT system image quality evaluation and may provide a practical tool for device validation and intercomparison.

  2. Modeling the thermo-acoustic effects of thermal-dependent speed of sound and acoustic absorption of biological tissues during focused ultrasound hyperthermia.

    Science.gov (United States)

    López-Haro, S A; Gutiérrez, M I; Vera, A; Leija, L

    2015-10-01

    To evaluate the effects of thermal dependence of speed of sound (SOS) and acoustic absorption of biological tissues during noninvasive focused ultrasound (US) hyperthermia therapy. A finite element (FE) model was used to simulate hyperthermia therapy in the liver by noninvasive focused US. The model consisted of an ultrasonic focused transducer radiating a four-layer biological medium composed of skin, fat, muscle, and liver. The acoustic field and temperature distribution along the layers were obtained after 15 s of hyperthermia therapy using the bio-heat equation. The model solution was found with and without the thermal dependence of SOS and acoustic absorption of biological tissues. The inclusion of the thermal dependence of the SOS generated an increment of 0.4 mm in the longitudinal focus axis of the acoustic field. Moreover, results indicate an increment of the hyperthermia area (zone with temperature above 43 °C), and a maximum temperature difference of almost 3.5 °C when the thermal dependence of absorption was taken into account. The increment of the achieved temperatures at the treatment zone indicated that the effects produced by the thermal dependence of SOS and absorption must be accounted for when planning hyperthermia treatment in order to avoid overheating undesired regions.

  3. Oceanography of East Madagascar

    Science.gov (United States)

    Bemiasa, John

    2014-05-01

    During six week survey (August - September 2008) in Southern and Eastern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. A total of 102 CTD stations were conducted along selected hydrographical transects and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, the first section between latitude 25o-26oS showed sea surface temperature values ranging between 25oC to 15oC upper 250m depth. As part of the south-west, the shelf is narrow and widen slightly along the tip south of the Island coast. In contrast of the west coast, in all transects performed along the south and the east coast, in most cases, the isotherms showed non stratified waters from the coast to offshore. The presence of the upwelling system in the south-east coast modifies drastically the patterns of all measured parameters. Fluorescence had a maximum values (0.25 µg/l) at surface near the coast in 2nd to 5th transects. Inversely, low temperature values were observed along the south and south-east with minimum values in the range of 18. 5oC-11oC at 50-250 m depth. These conditions were consistent along and between the 2nd to 5th transects, with more variation observed at transect 5. The salinity values (5 m depth) decreased from 35.7 psu in the south to 34.5 psu in the east. The horizontal distribution of oxygen showed non homogenous conditions with values between 5 ml/l (south) and 2.5 ml/l (south-east). Also starting from the coast to offshore, surface temperatures and surface salinities, surface

  4. Using Oceanography to Support Active Learning

    Science.gov (United States)

    Byfield, V.

    2012-04-01

    Teachers are always on the lookout for material to give their brightest students, in order to keep them occupied, stimulated and challenged, while the teacher gets on with helping the rest. They are also looking for material that can inspire and enthuse those who think that school is 'just boring!' Oceanography, well presented, has the capacity to do both. As a relatively young science, oceanography is not a core curriculum subject (possibly an advantage), but it draws on the traditional sciences of biology, chemistry, physic and geology, and can provide wonderful examples for teaching concepts in school sciences. It can also give good reasons for learning science, maths and technology. Exciting expeditions (research cruises) to far-flung places; opportunities to explore new worlds, a different angle on topical debates such as climate change, pollution, or conservation can bring a new life to old subjects. Access to 'real' data from satellites or Argo floats can be used to develop analytical and problem solving skills. The challenge is to make all this available in a form that can easily be used by teachers and students to enhance the learning experience. We learn by doing. Active teaching methods require students to develop their own concepts of what they are learning. This stimulates new neural connections in the brain - the physical manifestation of learning. There is a large body of evidence to show that active learning is much better remembered and understood. Active learning develops thinking skills through analysis, problem solving, and evaluation. It helps learners to use their knowledge in realistic and useful ways, and see its importance and relevance. Most importantly, properly used, active learning is fun. This paper presents experiences from a number of education outreach projects that have involved the National Oceanography Centre in Southampton, UK. All contain some element of active learning - from quizzes and puzzles to analysis of real data from

  5. Operational oceanography: Shall we dance?

    Science.gov (United States)

    Mooers, Christopher N. K.

    With the Global Ocean Observing System (GOOS) currently in development, the worldwide oceanographic community is on the brink of “operational oceanography,” which essentially means provision of “operational ocean services” where “operational” means “routine” and “ocean services” means “marine environmental information.” GOOS is a joint campaign of the Intergovernmental Oceanographic Commission, the World Meteorological Organization, the United Nations Environmental Program, and the International Council for Science. GOOS will integrate expanded real-time in situ and satellite observations with numerical models to form model-based information products for a multiplicity of societal needs, including scientific research [Stel, 1997].Operational oceanography has become a popular tune without a copyright but with many bandmasters. While Europeans and northeast Asians are moving ahead aggressively with GOOS activities, the United States has been hesitant, lacking in foresight, and awash in planning activities. It is time to ask, What has happened?, What is happening?, and What should happen?

  6. Reliable discrimination of high explosive and chemical/biological artillery using acoustic UGS

    Science.gov (United States)

    Hohil, Myron E.; Desai, Sachi

    2005-10-01

    The Army is currently developing acoustic overwatch sensor systems that will provide extended range surveillance, detection, and identification for force protection and tactical security on the battlefield. A network of such sensors remotely deployed in conjunction with a central processing node (or gateway) will provide early warning and assessment of enemy threats, near real-time situational awareness to commanders, and may reduce potential hazards to the soldier. In contrast, the current detection of chemical/biological (CB) agents expelled into a battlefield environment is limited to the response of chemical sensors that must be located within close proximity to the CB agent. Since chemical sensors detect hazardous agents through contact, the sensor range to an airburst is the key-limiting factor in identifying a potential CB weapon attack. The associated sensor reporting latencies must be minimized to give sufficient preparation time to field commanders, who must assess if an attack is about to occur, has occurred, or if occurred, the type of agent that soldiers might be exposed to. The long-range propagation of acoustic blast waves from heavy artillery blasts, which are typical in a battlefield environment, introduces a feature for using acoustics and other disparate sensor technologies for the early detection and identification of CB threats. Employing disparate sensor technologies implies that warning of a potential CB attack can be provided to the solider more rapidly and from a safer distance when compared to that which conventional methods allow. This capability facilitates the necessity of classifying the types of rounds that have burst in a specified region in order to give both warning and provide identification of CB agents found in the area. In this paper, feature extraction methods based on the discrete wavelet transform (DWT) and multiresolution analysis facilitate the development of a robust classification algorithm that affords reliable

  7. Fundamentals of estuarine physical oceanography

    CERN Document Server

    Bruner de Miranda, Luiz; Kjerfve, Björn; Castro Filho, Belmiro Mendes de

    2017-01-01

    This book provides an introduction to the complex system functions, variability and human interference in ecosystem between the continent and the ocean. It focuses on circulation, transport and mixing of estuarine and coastal water masses, which is ultimately related to an understanding of the hydrographic and hydrodynamic characteristics (salinity, temperature, density and circulation), mixing processes (advection and diffusion), transport timescales such as the residence time and the exposure time. In the area of physical oceanography, experiments using these water bodies as a natural laboratory and interpreting their circulation and mixing processes using theoretical and semi-theoretical knowledge are of fundamental importance. Small-scale physical models may also be used together with analytical and numerical models. The book highlights the fact that research and theory are interactive, and the results provide the fundamentals for the development of the estuarine research.

  8. Oceanography Information System of Spanish Institute of Oceanography (IEO)

    Science.gov (United States)

    Tello, Olvido; Gómez, María; González, Sonsoles

    2016-04-01

    Since 1914, the Spanish Institute of Oceanography (IEO) performs multidisciplinary studies of the marine environment. In same case are systematic studies and in others are specific studies for special requirements (El Hierro submarine volcanic episode, spill Prestige, others.). Different methodologies and data acquisition techniques are used depending on studies aims. The acquired data are stored and presented in different formats. The information is organized into different databases according to the subject and the variables represented (geology, fisheries, aquaculture, pollution, habitats, etc.). Related to physical and chemical oceanography data, in 1964 was created the DATA CENTER of IEO (CEDO), in order to organize the data about physical and chemical variables, to standardize this information and to serve the international data network SeaDataNet. www.seadatanet.org. This database integrates data about temperature, salinity, nutrients, and tidal data. CEDO allows consult and download the data. http://indamar.ieo.es On the other hand, related to data about marine species in 1999 was developed SIRENO DATABASE. All data about species collected in oceanographic surveys carried out by researches of IEO, and data from observers on fishing vessels are incorporated in SIRENO database. In this database is stored catch data, biomass, abundance, etc. This system is based on architecture ORACLE. Due to the large amount of information collected over the 100 years of IEO history, there is a clear need to organize, standardize, integrate and relate the different databases and information, and to provide interoperability and access to the information. Consequently, in 2000 it emerged the first initiative to organize the IEO spatial information in an Oceanography Information System, based on a Geographical Information System (GIS). The GIS was consolidated as IEO institutional GIS and was created the Spatial Data Infrastructure of IEO (IDEO) following trend of INSPIRE. All

  9. Development and validation of a biologically realistic tissue-mimicking material for photoacoustics and other bimodal optical-acoustic modalities

    Science.gov (United States)

    Vogt, William C.; Jia, Congxian; Wear, Keith A.; Garra, Brian S.; Pfefer, T. Joshua

    2017-03-01

    Recent years have seen rapid development of hybrid optical-acoustic imaging modalities with broad applications in research and clinical imaging, including photoacoustic tomography (PAT), photoacoustic microscopy, and ultrasound-modulated optical tomography. Tissue-mimicking phantoms are an important tool for objectively and quantitatively simulating in vivo imaging system performance. However, no standard tissue phantoms exist for such systems. One major challenge is the development of tissue-mimicking materials (TMMs) that are both highly stable and possess biologically realistic properties. To address this need, we have explored the use of various formulations of PVC plastisol (PVCP) based on varying mixtures of several liquid plasticizers. We developed a custom PVCP formulation with optical absorption and scattering coefficients, speed of sound, and acoustic attenuation that are tunable and tissue-relevant. This TMM can simulate different tissue compositions and offers greater mechanical strength than hydrogels. Optical properties of PVCP samples with varying composition were characterized using integrating sphere spectrophotometry and the inverse adding-doubling method. Acoustic properties were determined using a broadband pulse-transmission technique. To demonstrate the utility of this bimodal TMM, we constructed an image quality phantom designed to enable quantitative evaluation of PAT spatial resolution. The phantom was imaged using a custom combined PAT-ultrasound imaging system. Results indicated that this more biologically realistic TMM produced performance trends not captured in simpler liquid phantoms. In the future, this TMM may be broadly utilized for performance evaluation of optical, acoustic, and hybrid optical-acoustic imaging systems.

  10. Cumulative and Synergistic Effects of Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use

    Science.gov (United States)

    2013-10-28

    Applied Physics Laboratory , University of Washington 1013 NE 40th Street Seattle, Washington 98105 Phone: 206-543-1343 email: Nystuen...NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Applied Physics Laboratory ,University of Washington... Hydroacoustics Near Marine-Terminating Glaciers”, Oceanography, vol. 25. Stabeno, P.J, Falry, E.V., Kachel, N.B., Moore, S., Mordy, C.W., Napp, J.M

  11. History of oceanography of the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Sengupta, R.

    This paper highlights history of the oceanography of the Indian Ocean. Oceanographic activities during Ancient period, Medieval period, British period, Post-Independence period are briefly discussed. The role of the IIOE, IOC, UNESCO are also...

  12. CSIR-National Institute of Oceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Tapaswi, M.P.

    CSIR-National Institute of Oceanography being one of its kind in the country The article describes the on-going researches and projects in contributing to the science in the field of Marine science....

  13. Auditory object salience: Human cortical processing of non-biological action sounds and their acoustic signal attributes

    Directory of Open Access Journals (Sweden)

    James W Lewis

    2012-05-01

    Full Text Available Whether viewed or heard, an object in action can be segmented from a background scene based on a number of different sensory cues. In the visual system, salient low-level attributes of an image are processed along parallel hierarchies, and involve intermediate stages, such as the lateral occipital cortices, wherein gross-level object form features are extracted prior to stages that show object specificity (e.g. for faces, buildings, or tools. In the auditory system, though relying on a rather different set of low-level signal attributes, a distinct acoustic event or auditory object can also be readily extracted from a background acoustic scene. However, it remains unclear whether cortical processing strategies used by the auditory system similarly extract gross-level aspects of acoustic object form that may be inherent to many real-world sounds. Examining mechanical and environmental action sounds, representing two distinct categories of non-biological and non-vocalization sounds, we had participants assess the degree to which each sound was perceived as a distinct object versus an acoustic scene. Using two functional magnetic resonance imaging (fMRI task paradigms, we revealed bilateral foci along the superior temporal gyri (STG showing sensitivity to the object-ness ratings of action sounds, independent of the category of sound and independent of task demands. Moreover, for both categories of sounds these regions also showed parametric sensitivity to spectral structure variations—a measure of change in entropy in the acoustic signals over time (acoustic form—while only the environmental sounds showed parametric sensitivity to mean entropy measures. Thus, similar to the visual system, the auditory system appears to include intermediate feature extraction stages that are sensitive to the acoustic form of action sounds, and may serve as a stage that begins to dissociate different categories of real-world auditory objects.

  14. Crucial times for Spanish physical oceanography

    Directory of Open Access Journals (Sweden)

    Josep L. Pelegrí

    2012-08-01

    Full Text Available The field of physical oceanography has undergone exponential growth in Spain during the last few decades. From a handful of self-taught researchers in the late 1960s there are now several hundred physical oceanographers distributed in some 20 Spanish institutions, and many more working overseas. The First Spanish Physical Oceanography Meeting (EOF1, held in Barcelona in October 2010, was a good example of the high quality and large variety of this research. The facilities and human resources are excellent but the alarming decrease in public investment in science due to the economic crisis must lead the Spanish physical oceanography community to define its current priorities. In this introductory paper to EOF1 we revise our history and where we are now, and suggest that progress in the near future will rely on our intelligence to sustain and enhance human capital, partnership and society-oriented research.

  15. 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

  16. The oceanography of winter leads

    Science.gov (United States)

    Morison, J. H.; McPhee, M. G.; Curtin, T. B.; Paulson, C. A.

    1992-07-01

    Leads in pack ice have long been considered important to the thermodynamics of the polar regions. A winter lead affects the ocean around it because it is a density source. As the surface freezes, salt is rejected and forms more dense water which sinks under the lead. This sets up a circulation with freshwater flowing in from the sides near the surface and dense water flowing away from the lead at the base of the mixed layer. If the mixed layer is fully turbulent, this pattern may not occur; rather, the salt rejected at the surface may simply mix into the surface boundary layer. In either event the instability produced at the surface of leads is the primary source of unstable buoyancy flux and, as such, exerts a strong influence on the mixed layer. Here as many as possible of the disparate and almost anecdotal observations of lead oceanography are assembled and combined with theoretical arguments to predict the form and scale of oceanographic disturbances caused by winter leads. The experimental data suggest the velocity disturbances associated with lead convection are about 1-5 cm s-1. These appear as jets near the surface and the base of the mixed layer when ice velocities across the lead are less than about 5 cm s-1. The salinity disturbances are about 0.01 to 0.05 psu. Scaling arguments suggest that the geostrophic currents set up by the lead density disturbances are also of the order of 1-5 cm s-1. The disturbances are most obvious when freezing is rapid and ice velocity is low because the salinity and velocity disturbances in the upper ocean are not smeared out by turbulence. In this vein, lead convection may be characterized at one extreme as free convection in which the density disturbance forces the circulation. At the other extreme, lead convection may be characterized as forced convection in which the density disturbance is mixed rapidly by boundary layer turbulence. The lead number Lo, which is the ratio of the pressure term to the turbulence term in the

  17. Development of an Introductory Oceanography Concept Inventory Survey

    Science.gov (United States)

    Arthurs, L.; Marchitto, T.

    2008-12-01

    Concept inventories are one type of assessment that can be used to evaluate whether a student has an accurate and working knowledge of a specific set of concepts. Although such assessment tools have been developed in astronomy, biology, chemistry, engineering, fluid mechanics, geology, and physics, none has been available. Our development of an Introductory Oceanography Concept Inventory Survey (IO-CIS) serves to fill this gap. Much of the development of the IO-CIS utilized students enrolled in the Spring 2008 Introduction to Oceanography course taught at the University of Colorado at Boulder. The first step in the development of IO-CIS involved the identification and selection of the critical concepts to be addressed in the course and the survey. Next, learning goals were defined for each critical concept. These learning goals then provided the basis for framing open-ended questions that were administered to students in pre-module in-class Concept Inventory Exercises (CIEs). These open-ended questions each underwent validation and revision with expert and novice input prior to being administered in a CIE. Each CIE comprised 4-5 open-ended questions, which each contained 1-4 parts. During the semester, 4 different CIEs were administered, with the number of respondents for each CIE ranging from 57-134. Student responses were then binned according to misconceptions and alternate conceptions, tallied, and "distractors" were written based on the most popular bins using the same language employed by students in their responses. Student responses were also used as part of the validation process to ensure that the questions were interpreted by students in the manner intended. Student responses were also used as a basis to discard particular questions from inclusion in the overall IO-CIS. After the initial IO-CIS questions and distractors had been designed as described above, 23 one-on-one student interviews were conducted as part of the validation process. As a result of

  18. IEOOS: the Spanish Institute of Oceanography Observing System

    Science.gov (United States)

    Tel, Elena; Balbin, Rosa; Cabanas, Jose-Manuel; Garcia, Maria-Jesus; Garcia-Martinez, M. Carmen; Gonzalez-Pola, Cesar; Lavin, Alicia; Lopez-Jurado, Jose-Luis; Rodriguez, Carmen; Ruiz-Villarreal, Manuel; Sánchez-Leal, Ricardo F.; Vargas-Yáñez, Manuel; Vélez-Belchí, Pedro

    2016-03-01

    Since its foundation, 100 years ago, the Spanish Institute of Oceanography (IEO) has been observing and measuring the ocean characteristics. Here is a summary of the initiatives of the IEO in the field of the operational oceanography. Some systems like the tide gauges network has been working for more than 70 years. The standard sections began at different moments depending on the local projects, and nowadays there are more than 180 coastal stations and deep-sea ones that are systematically sampled, obtaining physical and biochemical measurements. At this moment, the Observing System includes six permanent moorings equipped with current meters, an open-sea ocean-meteorological buoy offshore Santander and a sea-surface temperature satellite image station. It also supports the Spanish contribution to the Argo international programme with 47 deployed profilers, and continuous monitoring thermosalinometers, meteorological stations and vessel-mounted acoustic Doppler current profilers on the research vessel fleet. The system is completed with the contribution to the Northwest Iberian peninsula and Gibraltar observatories, and the development of regional prediction models. All these systematic measurements allow the IEO to give responses to ocean research activities, official agencies requirements and industrial and main society demands such as navigation, resource management, risks management, recreation, as well as for management development pollution-related economic activities or marine ecosystems. All these networks are linked to international initiatives, framed largely in supranational programmes of Earth observation sponsored by the United Nations or the European Union. The synchronic observation system permits a spatio-temporal description of some events, such as new deep water formation in the Mediterranean Sea and the injection of heat to intermediate waters in the Bay of Biscay after some colder northern storms in winter 2005.

  19. Naval Meteorology and Oceanography Command exhibit

    Science.gov (United States)

    2000-01-01

    Designed to entertain while educating, StenniSphere at the John C. Stennis Space Center in Hancock County, Miss., includes informative displays and exhibits from NASA and other agencies located at Stennis, such as this one from the Naval Meteorology and Oceanography Command. Visitors can 'travel' three-dimensionally under the sea and check on the weather back home in the Weather Center. StenniSphere is open free of charge from 9 a.m. to 5 p.m. daily.

  20. Naval Meteorology and Oceanography Command exhibit entrance

    Science.gov (United States)

    2000-01-01

    StenniSphere at NASA's John C. Stennis Space Center in Hancock County, Miss., invites visitors to discover why America comes to Stennis Space Center before going into space. Designed to entertain while educating, StenniSphere includes informative displays and exhibits from NASA and other agencies located at Stennis, such as this one from the Naval Meteorology and Oceanography Command. Visitors can 'travel' three-dimensionally under the sea and check on the weather back home in the Weather Center.

  1. SWOT Oceanography and Hydrology Data Product Simulators

    Science.gov (United States)

    Peral, Eva; Rodriguez, Ernesto; Fernandez, Daniel Esteban; Johnson, Michael P.; Blumstein, Denis

    2013-01-01

    The proposed Surface Water and Ocean Topography (SWOT) mission would demonstrate a new measurement technique using radar interferometry to obtain wide-swath measurements of water elevation at high resolution over ocean and land, addressing the needs of both the hydrology and oceanography science communities. To accurately evaluate the performance of the proposed SWOT mission, we have developed several data product simulators at different levels of fidelity and complexity.

  2. Passive acoustic monitoring of toothed whales with implications for mitigation, management and biology

    DEFF Research Database (Denmark)

    Kyhn, Line Anker

    Toothed whales are vocal animals and their social life as well as successful orientation and feeding depends on emission and reception of sound. Such sounds may e.g. be clicks used for echolocation or whistles used for communication and they can be monitored in time and space by means of passive...... importantly the detection functions derived per datalogger could level out the sensitivity differences between the dataloggers (chapter II). Knowing that passive acoustic monitoring may be used to derive densities of small odontocetes such as NBHF species, the next step is to obtain accurate click...... descriptions. A species' sounds must be well defined according to specific sound source parameters to be able to build precise filters for the acoustic dataloggers to sort the correct signals from noise. Such definitions require that the variation at the level of species is known and therefore that each focal...

  3. JARE-43 Tangaroa marine science cruise report (Physical oceanography

    Directory of Open Access Journals (Sweden)

    Shigeru Aoki

    2004-11-01

    Full Text Available To understand the seasonal variation of biological and biogeochemical cycles in the seasonal ice zone in the Southern Ocean, the cruise of JARE-STAGE (Japanese Antarctic Research Expedition-Studies on Antarctic Ocean and Global Environment was conducted in February 2002 with R/V Tangaroa. Physical oceanography implementations of the cruise are described. The results of the manufacturers' CTD conductivity calibrations were consistent between before and after the cruise, and the difference in salinity estimate was expected to be within 0.0014. Two casts were made to validate the XCTD accuracy and comparisons with the CTD are discussed. Generally, it is concluded that reasonably accurate observations were completed in this cruise.

  4. 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...

  5. From satellite altimetry to Argo and operational oceanography: three revolutions in oceanography

    Science.gov (United States)

    Le Traon, P. Y.

    2013-10-01

    The launch of the French/US mission Topex/Poseidon (T/P) (CNES/NASA) in August 1992 was the start of a revolution in oceanography. For the first time, a very precise altimeter system optimized for large-scale sea level and ocean circulation observations was flying. T/P alone could not observe the mesoscale circulation. In the 1990s, the ESA satellites ERS-1/2 were flying simultaneously with T/P. Together with my CLS colleagues, we demonstrated that we could use T/P as a reference mission for ERS-1/2 and bring the ERS-1/2 data to an accuracy level comparable to T/P. Near-real-time high-resolution global sea level anomaly maps were then derived. These maps have been operationally produced as part of the SSALTO/DUACS system for the last 15 yr. They are now widely used by the oceanographic community and have contributed to a much better understanding and recognition of the role and importance of mesoscale dynamics. Altimetry needs to be complemented with global in situ observations. At the end of the 90s, a major international initiative was launched to develop Argo, the global array of profiling floats. This has been an outstanding success. Argo floats now provide the most important in situ observations to monitor and understand the role of the ocean on the earth climate and for operational oceanography. This is a second revolution in oceanography. The unique capability of satellite altimetry to observe the global ocean in near-real-time at high resolution and the development of Argo were essential for the development of global operational oceanography, the third revolution in oceanography. The Global Ocean Data Assimilation Experiment (GODAE) was instrumental in the development of the required capabilities. This paper provides an historical perspective on the development of these three revolutions in oceanography which are very much interlinked. This is not an exhaustive review and I will mainly focus on the contributions we made together with many colleagues and

  6. Auditory object salience: human cortical processing of non-biological action sounds and their acoustic signal attributes.

    Science.gov (United States)

    Lewis, James W; Talkington, William J; Tallaksen, Katherine C; Frum, Chris A

    2012-01-01

    Whether viewed or heard, an object in action can be segmented as a distinct salient event based on a number of different sensory cues. In the visual system, several low-level attributes of an image are processed along parallel hierarchies, involving intermediate stages wherein gross-level object form and/or motion features are extracted prior to stages that show greater specificity for different object categories (e.g., people, buildings, or tools). In the auditory system, though relying on a rather different set of low-level signal attributes, meaningful real-world acoustic events and "auditory objects" can also be readily distinguished from background scenes. However, the nature of the acoustic signal attributes or gross-level perceptual features that may be explicitly processed along intermediate cortical processing stages remain poorly understood. Examining mechanical and environmental action sounds, representing two distinct non-biological categories of action sources, we had participants assess the degree to which each sound was perceived as object-like versus scene-like. We re-analyzed data from two of our earlier functional magnetic resonance imaging (fMRI) task paradigms (Engel et al., 2009) and found that scene-like action sounds preferentially led to activation along several midline cortical structures, but with strong dependence on listening task demands. In contrast, bilateral foci along the superior temporal gyri (STG) showed parametrically increasing activation to action sounds rated as more "object-like," independent of sound category or task demands. Moreover, these STG regions also showed parametric sensitivity to spectral structure variations (SSVs) of the action sounds-a quantitative measure of change in entropy of the acoustic signals over time-and the right STG additionally showed parametric sensitivity to measures of mean entropy and harmonic content of the environmental sounds. Analogous to the visual system, intermediate stages of the

  7. Auditory object salience: human cortical processing of non-biological action sounds and their acoustic signal attributes

    Science.gov (United States)

    Lewis, James W.; Talkington, William J.; Tallaksen, Katherine C.; Frum, Chris A.

    2012-01-01

    Whether viewed or heard, an object in action can be segmented as a distinct salient event based on a number of different sensory cues. In the visual system, several low-level attributes of an image are processed along parallel hierarchies, involving intermediate stages wherein gross-level object form and/or motion features are extracted prior to stages that show greater specificity for different object categories (e.g., people, buildings, or tools). In the auditory system, though relying on a rather different set of low-level signal attributes, meaningful real-world acoustic events and “auditory objects” can also be readily distinguished from background scenes. However, the nature of the acoustic signal attributes or gross-level perceptual features that may be explicitly processed along intermediate cortical processing stages remain poorly understood. Examining mechanical and environmental action sounds, representing two distinct non-biological categories of action sources, we had participants assess the degree to which each sound was perceived as object-like versus scene-like. We re-analyzed data from two of our earlier functional magnetic resonance imaging (fMRI) task paradigms (Engel et al., 2009) and found that scene-like action sounds preferentially led to activation along several midline cortical structures, but with strong dependence on listening task demands. In contrast, bilateral foci along the superior temporal gyri (STG) showed parametrically increasing activation to action sounds rated as more “object-like,” independent of sound category or task demands. Moreover, these STG regions also showed parametric sensitivity to spectral structure variations (SSVs) of the action sounds—a quantitative measure of change in entropy of the acoustic signals over time—and the right STG additionally showed parametric sensitivity to measures of mean entropy and harmonic content of the environmental sounds. Analogous to the visual system, intermediate stages

  8. Acoustic pressure amplitude thresholds for rectified diffusion in gaseous microbubbles in biological tissue

    DEFF Research Database (Denmark)

    Lewin, Peter A.; Jensen, Leif Bjørnø

    1981-01-01

    One of the mechanisms often suggested for the biological action of ultrasonic beams irradiating human tissues is concerned with the presence in the tissues of minute gaseous bubbles which may, under the influence of the ultrasonic field be stimulated to grow to a size at which resonance or collap...... of calculations for typical (transient) exposure conditions from pulse-echo equipment are presented, indicating that rectified diffusion and stable cavitation are improbable phenomena in these circumstances....

  9. Argo workstation: a key component of operational oceanography

    Science.gov (United States)

    Dong, Mingmei; Xu, Shanshan; Miao, Qingsheng; Yue, Xinyang; Lu, Jiawei; Yang, Yang

    2018-02-01

    Operational oceanography requires the quantity, quality, and availability of data set and the timeliness and effectiveness of data products. Without steady and strong operational system supporting, operational oceanography will never be proceeded far. In this paper we describe an integrated platform named Argo Workstation. It operates as a data processing and management system, capable of data collection, automatic data quality control, visualized data check, statistical data search and data service. After it is set up, Argo workstation provides global high quality Argo data to users every day timely and effectively. It has not only played a key role in operational oceanography but also set up an example for operational system.

  10. From satellite altimetry to operational oceanography and Argo: three revolutions in oceanography (Fridtjof Nansen Medal Lecture)

    Science.gov (United States)

    Le Traon, P. Y.

    2012-04-01

    The launch of the US/French mission Topex/Poseidon (T/P) (CNES/NASA) in August 1992 was the start of a revolution in oceanography. For the first time, a very precise altimeter system optimized for large scale sea level and ocean circulation observations was flying. Topex/Poseidon revolutionized our vision and understanding of the ocean. It provided new views of the large scale seasonal and interannual sea level and ocean circulation variations. T/P alone could not observe the mesoscale circulation. In the 1990s, the ESA satellites ERS-1/2 were flying simultaneously with T/P. The ERS-1/2 orbit was well adapted for mesoscale circulation sampling but the orbit determination and altimeter performance were much less precise than for T/P. We demonstrated that we could use T/P as a reference mission for ERS-1/2 and bring the ERS-1/2 data to an accuracy level comparable to T/P. This was an essential first step for the merging of T/P and ERS-1/2. The second step required the development of a global optimal interpolation method. Near real time high resolution global sea level anomaly maps were then derived. These maps have been operationally produced as part of the SSALTO/DUACS system for the last 15 years. They are now widely used by the oceanographic community and have contributed to a much better understanding and recognition of the role and importance of mesoscale dynamics. The unique capability of satellite altimetry to observe the global ocean in near real time at high resolution was essential to the development of global ocean forecasting, a second revolution in oceanography. The Global Ocean Data Assimilation Experiment (GODAE) (1998-2008) was phased with the T/P and ERS-1/2 successors (Jason-1 and ENVISAT) and was instrumental in the development of global operational oceanography capabilities. Europe played a leading role in GODAE. In 1998, the global in-situ observing system was inadequate for the global scope of GODAE. This led to the development of Argo, an

  11. A Dry Membrane Protection Technique to Allow Surface Acoustic Wave Biosensor Measurements of Biological Model Membrane Approaches

    Directory of Open Access Journals (Sweden)

    Marius Enachescu

    2013-09-01

    Full Text Available Model membrane approaches have attracted much attention in biomedical sciences to investigate and simulate biological processes. The application of model membrane systems for biosensor measurements is partly restricted by the fact that the integrity of membranes critically depends on the maintenance of an aqueous surrounding, while various biosensors require a preconditioning of dry sensors. This is for example true for the well-established surface acoustic wave (SAW biosensor SAM®5 blue. Here, a simple drying procedure of sensor-supported model membranes is introduced using the protective disaccharide trehalose. Highly reproducible model membranes were prepared by the Langmuir-Blodgett technique, transferred to SAW sensors and supplemented with a trehalose solution. Membrane rehydration after dry incorporation into the SAW device becomes immediately evident by phase changes. Reconstituted model membranes maintain their full functionality, as indicated by biotin/avidin binding experiments. Atomic force microscopy confirmed the morphological invariability of dried and rehydrated membranes. Approximating to more physiological recognition phenomena, the site-directed immobilization of the integrin VLA-4 into the reconstituted model membrane and subsequent VCAM-1 ligand binding with nanomolar affinity were illustrated. This simple drying procedure is a novel way to combine the model membrane generation by Langmuir-Blodgett technique with SAW biosensor measurements, which extends the applicability of SAM®5 blue in biomedical sciences.

  12. The Maury Project: Exploring the Physical Foundations of Oceanography

    National Research Council Canada - National Science Library

    Geer, Ira

    1997-01-01

    .... The Maury Project is an oceanography-based graduate-level precollege teacher enhancement program, designed to promote the scientific literacy of young people by improving the background of pre...

  13. Scripps Institution of Oceanography Ferromanganese Nodule Analysis File - IDOE Portion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Scripps Institution of Oceanography (SIO) compiled data on the geochemistry of marine ferromanganese nodules, funded by the U.S. National Science Foundation...

  14. The ARMADA Project: Bringing Oceanography and the Arctic to the Midwest

    Science.gov (United States)

    Pazol, J.

    2010-12-01

    In the fall of 2009, I spent 6 weeks aboard the Coast Guard Icebreaker Healy on a mapping expedition in the Arctic Ocean, through participation in the University of Rhode Island's ARMADA Project. Because I grew up in the Midwest, went to college here, and teach in the Chicago suburbs, I had limited first-hand experience in oceanography, as did most of my students. During my time aboard the ship, I primarily served as a member of the mapping team, collecting bathymetric and seismic data. My other science activities included aiding geologists and acoustic engineers in dredging projects and deployment of under-ice recording devices. I collected water data, sent off weather balloons, and assisted marine mammal observers. For the ARMADA Project I kept an on-line journal, which had a far-reaching impact. Students in many schools kept track of my activities and communicated with me via e-mail. Colleagues and friends shared the journal through other media, such as Facebook. Several of my entries were published in blogs belonging to NOAA and the USGS. I received a grant for renting a satellite phone, and through it was able to make "Live from the Arctic" phone calls. After introductory PowerPoints I communicated with more than 420 students in 5 schools in 3 states. When I returned, I made a series of presentations about the Arctic and my adventures to hundreds of people and was featured in an educational magazine with a circulation of more than 90,000. I also participated in an in-depth mentoring program with a new teacher to help her succeed during the first years of her career. The results: My students and I now have a direct connection to the Arctic and to the fields of oceanography, acoustic engineering, and geology. On their own initiative, students have developed individual projects exploring aspects of my research. They have attended presentations from the Extreme Ice Center and have become involved in drilling issues in the Chukchi Sea. A group of students is

  15. Imaging and quantitative data acquisition of biological cell walls with Atomic Force Microscopy and Scanning Acoustic Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tittmann, B. R. [Penn State; Xi, X. [Penn State

    2014-09-01

    This chapter demonstrates the feasibility of Atomic Force Microscopy (AFM) and High Frequency Scanning Acoustic Microscopy (HF-SAM) as tools to characterize biological tissues. Both the AFM and the SAM have shown to provide imaging (with different resolution) and quantitative elasticity measuring abilities. Plant cell walls with minimal disturbance and under conditions of their native state have been examined with these two kinds of microscopy. After descriptions of both the SAM and AFM, their special features and the typical sample preparation is discussed. The sample preparation is focused here on epidermal peels of onion scales and celery epidermis cells which were sectioned for the AFM to visualize the inner surface (closest to the plasma membrane) of the outer epidermal wall. The nm-wide cellulose microfibrils orientation and multilayer structure were clearly observed. The microfibril orientation and alignment tend to be more organized in older scales compared with younger scales. The onion epidermis cell wall was also used as a test analog to study cell wall elasticity by the AFM nanoindentation and the SAM V(z) feature. The novelty in this work was to demonstrate the capability of these two techniques to analyze isolated, single layered plant cell walls in their natural state. AFM nanoindentation was also used to probe the effects of Ethylenediaminetetraacetic acid (EDTA), and calcium ion treatment to modify pectin networks in cell walls. The results suggest a significant modulus increase in the calcium ion treatment and a slight decrease in EDTA treatment. To complement the AFM measurements, the HF-SAM was used to obtain the V(z) signatures of the onion epidermis. These measurements were focused on documenting the effect of pectinase enzyme treatment. The results indicate a significant change in the V(z) signature curves with time into the enzyme treatment. Thus AFM and HF-SAM open the door to a systematic nondestructive structure and mechanical property

  16. Marine ecosystem acoustics (MEA): Quantifying processes in the sea at the spatio-temporal scales on which they occur

    KAUST Repository

    Godøl, Olav Rune

    2014-07-22

    Sustainable management of fisheries resources requires quantitative knowledge and understanding of species distribution, abundance, and productivity-determining processes. Conventional sampling by physical capture is inconsistent with the spatial and temporal scales on which many of these processes occur. In contrast, acoustic observations can be obtained on spatial scales from centimetres to ocean basins, and temporal scales from seconds to seasons. The concept of marine ecosystem acoustics (MEA) is founded on the basic capability of acoustics to detect, classify, and quantify organisms and biological and physical heterogeneities in the water column. Acoustics observations integrate operational technologies, platforms, and models and can generate information by taxon at the relevant scales. The gaps between single-species assessment and ecosystem-based management, as well as between fisheries oceanography and ecology, are thereby bridged. The MEA concept combines state-of-the-art acoustic technology with advanced operational capabilities and tailored modelling integrated into a flexible tool for ecosystem research and monitoring. Case studies are presented to illustrate application of the MEA concept in quantification of biophysical coupling, patchiness of organisms, predator-prey interactions, and fish stock recruitment processes. Widespread implementation of MEA will have a large impact on marine monitoring and assessment practices and it is to be hoped that they also promote and facilitate interaction among disciplines within the marine sciences.

  17. Marine Biology and Oceanography, Grades Nine to Twelve. Part II.

    Science.gov (United States)

    Kolb, James A.

    This unit, one of a series designed to develop and foster an understanding of the marine environment, presents marine science activities for students in grades 9-12. The unit, focusing on sea plants/animals and their interactions with each other and the non-living environment, has sections dealing with: marine ecology; marine bacteriology;…

  18. The Impact of Very High Frequency Surface Reverberation on Coherent Acoustic Propagation and Modeling

    Science.gov (United States)

    2015-09-30

    on Coherent Acoustic Propagation and Modeling Grant B. Deane Marine Physical Laboratory , Scripps Institution of Oceanography UCSD La Jolla, CA...long-term science objective is to develop a physical model of high-frequency scattering of underwater acoustic signals from the sea surface under a... acoustic communications problem. The scattering of sound from the sea surface is important for the operation of underwater sonar and underwater

  19. The status of coastal oceanography in heavily impacted Yellow and East China Sea: Past trends, progress, and possible futures

    Science.gov (United States)

    Wang, Xiao Hua; Cho, Yang-Ki; Guo, Xinyu; Wu, Chau-Ron; Zhou, Junliang

    2015-09-01

    Coastal environments are a key location for transport, commercial, residential and defence infrastructure, and have provided conditions suitable for economic growth. They also fulfil important cultural, recreational and aesthetic needs; have intrinsic ecosystem service values; and provide essential biogeochemical functions such as primary productivity, nutrient cycling and water filtration. The rapid expansion in economic development and anticipated growth of the population in the coastal zones along the Yellow and East China Sea basin has placed this region under intense multiple stresses. Here we aim to: 1) synthesize the new knowledge/science in coastal oceanography since 2010 within the context of the scientific literature published in English; 2) report on a citation analysis that assesses whether new research topics have emerged and integrated over time, indicate the location of modelling and field-based studies; and 3) suggest where the new research should develop for heavily impacted estuaries and coastal seas of East Asia. The conclusions of the synthesis include: 1) China has emerged as a dominant force in the region in producing scientific literature in coastal oceanography, although the area of publications has shifted from its traditional fields such as physical oceanography; 2) there has been an increasing number of publications with cross-disciplinary themes between physical oceanography and other fields of the biological, chemical, and geological disciplines, but vigorous and systematic funding mechanisms are still lacking to ensure the viability of large scale multi-disciplinary teams and projects in order to support trans-disciplinary research and newly emerging fields; 3) coastal oceanography is responding to new challenges, with many papers studying the impacts of human activities on marine environment and ecology, but so far very few studying management and conservation strategies or offering policy solutions.

  20. The Physical Oceanography of Australia's Sunshine Coast

    Science.gov (United States)

    Ribbe, Joachim

    2017-04-01

    Australia's Sunshine coast is located to the south of the Great Barrier Reef and Fraser Island between about 25 oS to 28 oS. With a width of nearly 70-80 km, the eastern Australian continental shelf is at its widest here. The shelf region is referred to as the Southeast Queensland Marine Coastal Zone due to its unique physical oceanographic characteristics. The most prominent large-scale oceanic feature is the southward flowing East Australian Current (EAC). It forms to the north of Fraser Island from Coral Sea outflows, intensifies, and follows the continental shelf as a swift continental shelf hugging current but variable in strength; stronger in the southern hemisphere summer and weaker in winter. Little attention has been paid to the physical oceanography of this region, although important physical processes take place that drive regional marine environmental conditions, drive cross-shelf exchanges and interactions with the EAC, and that represent marine connectivity processes significant to the larger scale eastern Australian fisheries. This presentation reviews recent discoveries that include the Southeast Fraser Island Upwelling System, the Fraser Island Gyre, and document the role of cyclonic mesoscale eddies in driving cross-shelf exchanges and contribute to the formation of the Fraser Island Gyre. The Southeast Fraser Island Upwelling System appears to be predominately driven by the interaction of the EAC with the continental shelf leading to the establishment of one of eight important marine ecological hotspots along the east Australian coast. The Fraser Island Gyre is most prominent during the southern hemisphere autumn and winter months. It is characterised by on-shelf northerly flow, turning eastward south of Fraser Island before joining the EAC. It emerges that cyclonic eddy formation as well as the south-easterly trade winds drive the gyre's establishment and strength. A census of short-lived (7-28 days) cyclonic eddies, the first for any western

  1. An oceanography summer school in Ghana, West Africa

    Science.gov (United States)

    Arbic, B. K.; Ansong, J. K.; Johnson, W.; Nyadjro, E. S.; Nyarko, E.

    2016-02-01

    Because oceanography is a global science, it clearly benefits from the existence of a world-wide network of oceanographers. As with most STEM disciplines, sub-Saharan Africa is not as well represented in the field of oceanography as it should be, given its large population. The need for oceanographers in sub-Saharan Africa is great, due to a long list of ocean-related issues affecting African development, including but not limited to fishing, oil drilling, sea level rise, coastal erosion, shipping, and piracy. We view this as an opportunity as well as a challenge. Many of the world's fastest growing economies are in sub-Saharan Africa, and STEM capacity building could further fuel this growth. With support from the US National Science Foundation, we ran an oceanography summer school from August 24-27, 2015, at the Regional Maritime University (RMU) in Ghana, West Africa. This first summer school was lecture-based, with a focus on basic chemical oceanography, basic physical oceanography, ocean modeling, and satellite oceanography. About 35 participants came to almost every lecture, and about 20 other participants came to some of the lectures as their time permitted. The participants included RMU faculty, 12 students from the Kwame Nkrumah University of Science and Technology, one Associate Oceanographer from the University of Ghana, and some participants from private sector companies and Ghanaian governmental agencies. There were long and lively discussions at the end of each lecture, and there was a lengthy discussion at the conclusion of the school on how to improve future summer schools. In 2016 and 2017, we plan to divide into smaller groups so that participants can pursue their particular interests in greater depth, and to allow time for student presentations. We also plan to begin exploring the potential for research partnerships, and to utilize distance learning to involve more faculty and students from locations throughout Ghana and perhaps from even other

  2. University Curricula in Oceanography and Related Fields.

    Science.gov (United States)

    1986-01-01

    offered: available in school catalog, shop, and sea turtle conservation and incubation area. Faculty appointments: available in school catalog. Large...to: total 20 semester hours, are: biochemistry, genetics, Chairman, Department of Zoology developmental biology ( embryology ), ecology, and com- ... 106

  3. Architectural acoustics

    National Research Council Canada - National Science Library

    Long, Marshall

    2014-01-01

    .... Beginning with a brief history, it reviews the fundamentals of acoustics, human perception and reaction to sound, acoustic noise measurements, noise metrics, and environmental noise characterization...

  4. Filling the gaps: Predicting the distribution of temperate reef biota using high resolution biological and acoustic data

    Science.gov (United States)

    Hill, Nicole A.; Lucieer, Vanessa; Barrett, Neville S.; Anderson, Tara J.; Williams, Stefan B.

    2014-06-01

    Management of the marine environment is often hampered by a lack of comprehensive spatial information on the distribution of diversity and the bio-physical processes structuring regional ecosystems. This is particularly true in temperate reef systems beyond depths easily accessible to divers. Yet these systems harbor a diversity of sessile life that provide essential ecosystem services, sustain fisheries and, as with shallower ecosystems, are also increasingly vulnerable to anthropogenic impacts and environmental change. Here we use cutting-edge tools (Autonomous Underwater Vehicles and ship-borne acoustics) and analytical approaches (predictive modelling) to quantify and map these highly productive ecosystems. We find the occurrence of key temperate-reef biota can be explained and predicted using standard (depth) and novel (texture) surrogates derived from multibeam acoustic data, and geographic surrogates. This suggests that combinations of fine-scale processes, such as light limitation and habitat complexity, and broad-scale processes, such as regional currents and exposure regimes, are important in structuring these diverse deep-reef communities. While some dominant habitat forming biota, including canopy algae, were widely distributed, others, including gorgonians and sea whips, exhibited patchy and restricted distributions across the reef system. In addition to providing the first quantitative and full coverage maps of reef diversity for this area, our modelling revealed that offshore reefs represented a regional diversity hotspot that is of high ecological and conservation value. Regional reef systems should not, therefore, be considered homogenous units in conservation planning and management. Full-coverage maps of the predicted distribution of biota (and associated uncertainty) are likely to be increasingly valuable, not only for conservation planning, but in the ongoing management and monitoring of these less-accessible ecosystems.

  5. 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....

  6. Acoustic telemetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To determine movements of green turtles in the nearshore foraging areas, we deployed acoustic tags and determined their movements through active and passive acoustic...

  7. West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume IV. Bibliography and supporting data for physical oceanography. Final report. [421 references

    Energy Technology Data Exchange (ETDEWEB)

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)

    1983-02-01

    This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which is located in southwestern Louisiana and which is designed to store 241 million barrels of crude oil. Oil storage caverns are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. Volume IV contains the following: bibliography; appendices for supporting data for physical oceanography, and summary of the physical oceanography along the western Louisiana coast.

  8. Dynamic oceanography determines fine scale foraging behavior of Masked Boobies in the Gulf of Mexico.

    Science.gov (United States)

    Poli, Caroline L; Harrison, Autumn-Lynn; Vallarino, Adriana; Gerard, Patrick D; Jodice, Patrick G R

    2017-01-01

    During breeding, foraging marine birds are under biological, geographic, and temporal constraints. These contraints require foraging birds to efficiently process environmental cues derived from physical habitat features that occur at nested spatial scales. Mesoscale oceanography in particular may change rapidly within and between breeding seasons, and findings from well-studied systems that relate oceanography to seabird foraging may transfer poorly to regions with substantially different oceanographic conditions. Our objective was to examine foraging behavior of a pan-tropical seabird, the Masked Booby (Sula dactylatra), in the understudied Caribbean province, a moderately productive region driven by highly dynamic currents and fronts. We tracked 135 individuals with GPS units during May 2013, November 2013, and December 2014 at a regionally important breeding colony in the southern Gulf of Mexico. We measured foraging behavior using characteristics of foraging trips and used area restricted search as a proxy for foraging events. Among individual attributes, nest stage contributed to differences in foraging behavior whereas sex did not. Birds searched for prey at nested hierarchical scales ranging from 200 m-35 km. Large-scale coastal and shelf-slope fronts shifted position between sampling periods and overlapped geographically with overall foraging locations. At small scales (at the prey patch level), the specific relationship between environmental variables and foraging behavior was highly variable among individuals but general patterns emerged. Sea surface height anomaly and velocity of water were the strongest predictors of area restricted search behavior in random forest models, a finding that is consistent with the characterization of the Gulf of Mexico as an energetic system strongly influenced by currents and eddies. Our data may be combined with tracking efforts in the Caribbean province and across tropical regions to advance understanding of seabird

  9. Dynamic oceanography determines fine scale foraging behavior of Masked Boobies in the Gulf of Mexico

    Science.gov (United States)

    Poli, Caroline L.; Harrison, Autumn-Lynn; Vallarino, Adriana; Gerard, Patrick D.; Jodice, Patrick G.R.

    2017-01-01

    During breeding, foraging marine birds are under biological, geographic, and temporal constraints. These contraints require foraging birds to efficiently process environmental cues derived from physical habitat features that occur at nested spatial scales. Mesoscale oceanography in particular may change rapidly within and between breeding seasons, and findings from well-studied systems that relate oceanography to seabird foraging may transfer poorly to regions with substantially different oceanographic conditions. Our objective was to examine foraging behavior of a pan-tropical seabird, the Masked Booby (Sula dactylatra), in the understudied Caribbean province, a moderately productive region driven by highly dynamic currents and fronts. We tracked 135 individuals with GPS units during May 2013, November 2013, and December 2014 at a regionally important breeding colony in the southern Gulf of Mexico. We measured foraging behavior using characteristics of foraging trips and used area restricted search as a proxy for foraging events. Among individual attributes, nest stage contributed to differences in foraging behavior whereas sex did not. Birds searched for prey at nested hierarchical scales ranging from 200 m—35 km. Large-scale coastal and shelf-slope fronts shifted position between sampling periods and overlapped geographically with overall foraging locations. At small scales (at the prey patch level), the specific relationship between environmental variables and foraging behavior was highly variable among individuals but general patterns emerged. Sea surface height anomaly and velocity of water were the strongest predictors of area restricted search behavior in random forest models, a finding that is consistent with the characterization of the Gulf of Mexico as an energetic system strongly influenced by currents and eddies. Our data may be combined with tracking efforts in the Caribbean province and across tropical regions to advance understanding of seabird

  10. Dynamic oceanography determines fine scale foraging behavior of Masked Boobies in the Gulf of Mexico.

    Directory of Open Access Journals (Sweden)

    Caroline L Poli

    Full Text Available During breeding, foraging marine birds are under biological, geographic, and temporal constraints. These contraints require foraging birds to efficiently process environmental cues derived from physical habitat features that occur at nested spatial scales. Mesoscale oceanography in particular may change rapidly within and between breeding seasons, and findings from well-studied systems that relate oceanography to seabird foraging may transfer poorly to regions with substantially different oceanographic conditions. Our objective was to examine foraging behavior of a pan-tropical seabird, the Masked Booby (Sula dactylatra, in the understudied Caribbean province, a moderately productive region driven by highly dynamic currents and fronts. We tracked 135 individuals with GPS units during May 2013, November 2013, and December 2014 at a regionally important breeding colony in the southern Gulf of Mexico. We measured foraging behavior using characteristics of foraging trips and used area restricted search as a proxy for foraging events. Among individual attributes, nest stage contributed to differences in foraging behavior whereas sex did not. Birds searched for prey at nested hierarchical scales ranging from 200 m-35 km. Large-scale coastal and shelf-slope fronts shifted position between sampling periods and overlapped geographically with overall foraging locations. At small scales (at the prey patch level, the specific relationship between environmental variables and foraging behavior was highly variable among individuals but general patterns emerged. Sea surface height anomaly and velocity of water were the strongest predictors of area restricted search behavior in random forest models, a finding that is consistent with the characterization of the Gulf of Mexico as an energetic system strongly influenced by currents and eddies. Our data may be combined with tracking efforts in the Caribbean province and across tropical regions to advance

  11. Effective, Active Learning Strategies for the Oceanography Classroom

    Science.gov (United States)

    Dmochowski, J. E.; Marinov, I.

    2014-12-01

    A decline in enrollment in STEM fields at the university level has prompted extensive research on alternative ways of teaching and learning science. Inquiry-based learning as well as the related "flipped" or "active" lectures, and similar teaching methods and philosophies have been proposed as more effective ways to disseminate knowledge in science classes than the traditional lecture. We will provide a synopsis of our experiences in implementing some of these practices into our Introductory Oceanography, Global Climate Change, and Ocean Atmosphere Dynamics undergraduate courses at the University of Pennsylvania, with both smaller and larger enrollments. By implementing tools such as at-home modules; computer labs; incorporation of current research; pre- and post-lecture quizzes; reflective, qualitative writing assignments; peer review; and a variety of in-class learning strategies, we aim to increase the science literacy of the student population and help students gain a more comprehensive knowledge of the topic, enhance their critical thinking skills, and correct misconceptions. While implementing these teaching techniques with college students is not without complications, we argue that a blended class that flexibly and creatively accounts for class size and science level improves the learning experience and the acquired knowledge. We will present examples of student assignments and activities as well as describe the lessons we have learned, and propose ideas for moving forward to best utilize innovative teaching tools in order to increase science literacy in oceanography and other climate-related courses.

  12. Acoustic cloaking and transformation acoustics

    Energy Technology Data Exchange (ETDEWEB)

    Chen Huanyang [School of Physical Science and Technology, Soochow University, Suzhou, Jiangsu 215006 (China); Chan, C T, E-mail: kenyon@ust.h, E-mail: phchan@ust.h [Department of Physics and the William Mong Institute of NanoScience and Technology, The Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong)

    2010-03-24

    In this review, we give a brief introduction to the application of the new technique of transformation acoustics, which draws on a correspondence between coordinate transformation and material properties. The technique is formulated for both acoustic waves and linear liquid surface waves. Some interesting conceptual devices can be designed for manipulating acoustic waves. For example, we can design acoustic cloaks that make an object invisible to acoustic waves, and the cloak can either encompass or lie outside the object to be concealed. Transformation acoustics, as an analog of transformation optics, can go beyond invisibility cloaking. As an illustration for manipulating linear liquid surface waves, we show that a liquid wave rotator can be designed and fabricated to rotate the wave front. The acoustic transformation media require acoustic materials which are anisotropic and inhomogeneous. Such materials are difficult to find in nature. However, composite materials with embedded sub-wavelength resonators can in principle be made and such 'acoustic metamaterials' can exhibit nearly arbitrary values of effective density and modulus tensors to satisfy the demanding material requirements in transformation acoustics. We introduce resonant sonic materials and Helmholtz resonators as examples of acoustic metamaterials that exhibit resonant behaviour in effective density and effective modulus. (topical review)

  13. 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.

  14. The oceanography programme of the Federal German Government

    International Nuclear Information System (INIS)

    1993-01-01

    The oceanography programme of the Federal German Government has the following general aims: 1. To lay the foundation for better understanding of the role of the ocean as a climate factor and repercussions on the ocean from climate change as a basis for future preventive and protective action. 2. Identification of natural and anthropogenous factors of stress to the coastal seas, the coastal regions and the open ocean, research into their dynamics and impact, and development of bases, methods and concepts for describing and evaluating the condition of the coastal seas, coastal regions and open ocean and for projecting and/or remedying relative changes. 3. Development of methods and techniques for climate and environment-related research into and monitoring of the oceans and for careful exploitation of living and non-living resources. (orig.) [de

  15. 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...

  16. Putting the Deep Biosphere on the Map for Oceanography Courses: Gas Hydrates As a Case Study for the Deep Biosphere

    Science.gov (United States)

    Sikorski, J. J.; Briggs, B. R.

    2014-12-01

    The ocean is essential for life on our planet. It covers 71% of the Earth's surface, is the source of the water we drink, the air we breathe, and the food we eat. Yet, the exponential growth in human population is putting the ocean and thus life on our planet at risk. However, based on student evaluations from our introductory oceanography course it is clear that our students have deficiencies in ocean literacy that impact their ability to recognize that the ocean and humans are inextricably connected. Furthermore, life present in deep subsurface marine environments is also interconnected to the study of the ocean, yet the deep biosphere is not typically covered in undergraduate oceanography courses. In an effort to improve student ocean literacy we developed an instructional module on the deep biosphere focused on gas hydrate deposits. Specifically, our module utilizes Google Earth and cutting edge research about microbial life in the ocean to support three inquiry-based activities that each explore different facets of gas hydrates (i.e. environmental controls, biologic controls, and societal implications). The relevant nature of the proposed module also makes it possible for instructors of introductory geology courses to modify module components to discuss related topics, such as climate, energy, and geologic hazards. This work, which will be available online as a free download, is a solid contribution toward increasing the available teaching resources focused on the deep biosphere for geoscience educators.

  17. The social oceanography of top oceanic predators and the decline of sharks: A call for a new field

    Science.gov (United States)

    Jacques, Peter J.

    2010-07-01

    The decline of top oceanic predators (TOPs), such as great sharks, and worldwide erosion of the marine food web is among the most important functional changes in marine systems. Yet, even though human pressures on sharks are one of the most important factors in the collapse of TOPs, the social science of shark fishing has not kept pace with the biophysical science. Such a gap highlights the need for a marine social science, and this paper uses the case of sharks to illustrate some advances that a coherent marine social science community could bring to science and sustainability, and calls for the development of this new field. Social oceanography is proposed as a “discursive space” that will allow multiple social science and humanities disciplines to holistically study and bring insight to a diverse but essential community. Such a community will not provide answers for the physical sciences, but it will add a new understanding of the contingencies that riddle social behavior that ultimately interact with marine systems. Such a field should reflect the broad and diverse approaches, epistemologies, philosophies of science and foci that are in the human disciplines themselves. Social oceanography would complete the triumvirate of biological and physical oceanography where human systems profoundly impact these other areas. This paper tests the theory that institutional rules are contingent on social priorities and paradigms. I used content analysis of all available (1995-2006) State of the World Fisheries and Aquaculture (SOFIA) reports from the United Nations Food and Agricultural Organization (FAO) to measure the symbolic behavior-i.e., what they say-as an indication of the value of sharks in world fisheries. Similar tests were also performed for marine journals and the Convention on Migratory Species of Wild Animals to corroborate these findings. Then, I present an institutional analysis of all international capacity building and regulatory institutions as they

  18. JPL Physical Oceanography Distributed Active Archive Center (PODAAC) Image Granules API

    Data.gov (United States)

    National Aeronautics and Space Administration — PO.DAAC provides several ways to discover and access physical oceanography data, from the PO.DAAC Web Portal to FTP access to front-end user interfaces (see...

  19. Physical oceanography - Developing end-to-end models of the California Current Large Marine Ecosystem

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to develop spatially discrete end-to-end models of the California Current LME, linking oceanography, biogeochemistry, food web...

  20. JPL Physical Oceanography Distributed Active Archive Center (PODAAC) Dataset Search API

    Data.gov (United States)

    National Aeronautics and Space Administration — PO.DAAC provides several ways to discover and access physical oceanography data, from the PO.DAAC Web Portal to FTP access to front-end user interfaces (see...

  1. Archive of Geosample Data and Information from the Scripps Institution of Oceanography (SIO) Geological Collections

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The University of California San Diego (UCSD) Scripps Institution of Oceanography (SIO) is a partner in the Index to Marine and Lacustrine Geological Samples (IMLGS)...

  2. Data analysis methods in physical oceanography. By Emery, W.J. and Thomson, R.E.

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, M.R.

    which deal with units in physical oceanography, statistical terminology; means, variances and moment generating functions for common con- tinuous variables; statistical tables; correlation coefficients and approximations and non-dimensional numbers...

  3. JPL Physical Oceanography Distributed Active Archive Center (PODAAC) Web Services API

    Data.gov (United States)

    National Aeronautics and Space Administration — PO.DAAC provides several ways to discover and access physical oceanography data, from the PO.DAAC Web Portal to FTP access to front-end user interfaces (see...

  4. Biology

    Indian Academy of Sciences (India)

    I am particularly happy that the Academy is bringing out this document by Professor M S. Valiathan on Ayurvedic Biology. It is an effort to place before the scientific community, especially that of India, the unique scientific opportunities that arise out of viewing Ayurveda from the perspective of contemporary science, its tools ...

  5. 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...

  6. Acoustic Neuroma

    Science.gov (United States)

    ... a team composed of neurosurgeons, radiation oncologists, medical physicists and a nursing staff. Specialists in neuroimaging join ... Even though most acoustic neuromas arise from the balance nerve (and not from the adjacent hearing nerve), ...

  7. Acoustic neuroma

    Science.gov (United States)

    ... Medical Professional Call your provider if you have: Hearing loss that is sudden or getting worse Ringing in one ear Dizziness (vertigo) Alternative Names Vestibular schwannoma; Tumor - acoustic; ... Patient Instructions Brain surgery - discharge ...

  8. 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....

  9. 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.

  10. Some aspects of biological production and fishery resources of the EEZ of India

    Digital Repository Service at National Institute of Oceanography (India)

    Bhargava, R.M.S.

    Region and season-wise biological production in the Exclusive Economic Zone (EEZ) of India has been computed from the data of more than twenty years available at the Indian National Oceanographic Data Centre of the National Institute of Oceanography...

  11. Biological processes in the water column of the South Atlantic bight

    Energy Technology Data Exchange (ETDEWEB)

    Paffenhoefer, G.A.; Yoder, J.A.

    1980-01-31

    Progress is reported on research conducted during 1979 on the biological oceanography of the South Atlantic Bight. The presentation consists of a number of published articles and abstracts of oral presentations. (ACR)

  12. Eddy-mediated biological productivity in the Bay of Bengal during fall and spring intermonsoons

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Nuncio, M.; Ramaiah, N.; Sardesai, S.; Narvekar, J.; Fernandes, V.; Paul, J.T.

    -1 Eddy-mediated biological productivity in the Bay of Bengal during fall and spring intermonsoons S. Prasanna Kumar, M. Nuncio, N. Ramaiah, S. Sardesai, Jayu Narvekar, Veronica Fernandes, Jane T. Paul National Institute of Oceanography, Dona Paula...

  13. Paleophysical oceanography with an emphasis on transport rates.

    Science.gov (United States)

    Huybers, Peter; Wunsch, Carl

    2010-01-01

    Paleophysical oceanography is the study of the behavior of the fluid ocean of the past, with a specific emphasis on its climate implications, leading to a focus on the general circulation. Even if the circulation is not of primary concern, heavy reliance on deep-sea cores for past climate information means that knowledge of the oceanic state when the sediments were laid down is a necessity. Like the modern problem, paleoceanography depends heavily on observations, and central difficulties lie with the very limited data types and coverage that are, and perhaps ever will be, available. An approximate separation can be made into static descriptors of the circulation (e.g., its water-mass properties and volumes) and the more difficult problem of determining transport rates of mass and other properties. Determination of the circulation of the Last Glacial Maximum is used to outline some of the main challenges to progress. Apart from sampling issues, major difficulties lie with physical interpretation of the proxies, transferring core depths to an accurate timescale (the "age-model problem"), and understanding the accuracy of time-stepping oceanic or coupled-climate models when run unconstrained by observations. Despite the existence of many plausible explanatory scenarios, few features of the paleocirculation in any period are yet known with certainty.

  14. IIth AMS Conference on Satellite Meteorology and Oceanography.

    Science.gov (United States)

    Velden, Christopher; Digirolamo, Larry; Glackin, Mary; Hawkins, Jeffrey; Jedlovec, Gary; Lee, Thomas; Petty, Grant; Plante, Robert; Reale, Anthony; Zapotocny, John

    2002-11-01

    The American Meteorological Society (AMS) held its 11th Conference on Satellite Meteorology and Oceanography at the Monona Terrace Convention Center in Madison, Wisconsin, during 15-18 October 2001. The purpose of the conference, typically held every 18 months, is to promote a forum for AMS membership, international scientists, and student members to present and discuss the latest advances in satellite remote sensing for meteorological and oceanographical applications. This year, surrounded by inspirational designs by famed architect Frank Lloyd Wright, the meeting focused on several broad topics related to remote sensing from space, including environmental applications of land and oceanic remote sensing, climatology and long-term satellite data studies, operational applications, radiances and retrievals, and new technology and methods. A vision of an increasing convergence of satellite systems emerged that included operational and research satellite programs and interdisciplinary user groups.The conference also hosted NASA's Electronic Theater, which was presented to groups of middle and high school students totaling over 5500. It was truly a successful public outreach event. The conference banquet was held on the final evening, where a short tribute to satellite pioneer Verner Suomi was given by Joanne Simpson. Suomi was responsible for establishing the Space Science and Engineering Center at the University of Wisconsin in Madison.

  15. Acoustically assisted diffusion through membranes and biomaterials

    International Nuclear Information System (INIS)

    Floros, J.D.; Liang, H.

    1994-01-01

    Part of a special section on the symposium ''Ultrasonic Applications in the Food Industry.'' The use of high-intensity ultrasound in food processing is reviewed. Acoustic radiation, or sound, can be used to monitor various operations or products or to alter a process or product; however, the direct use of sound to improve food processes is not very popular. High-intensity acoustic radiation induces various changes as it passes through a medium, largely as a result of heating, cavitation, agitation and shear stresses, compression and rarefaction, and turbulence. The diffusion of sound through a medium is influenced by factors such as the temperature, acoustic intensity, acoustic frequency, direction of the acoustic wave, pulsation of the acoustic wave, and properties of the medium. Some potential applications of acoustic energy in food processes are increased drying efficiency, acceleration of diffusion through polymeric and biological membranes, and enhanced diffusion through porous materials

  16. Effect of Ocean Interannual Variability on Acoustic Propagation in the Philippine Sea and South China Sea

    Science.gov (United States)

    2017-06-01

    Philippine Sea and South China Sea. Recently, a Synoptic Monthly Gridded World Ocean Database (SMG-WOD) with horizontal resolution of 1o world - wide ...Gridded World Ocean Database (SMG- WOD) data from January 1960 to December 2014, and an open source acoustic model (BELLHOP). The multi-year averaged...partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN METEOROLOGY AND PHYSICAL OCEANOGRAPHY from the NAVAL

  17. Tactile Digital Video Globes: a New Way to Outreach Oceanography.

    Science.gov (United States)

    Poteau, A.; Claustre, H.; Scheurle, C.; Jessin, T.; Fontana, C.

    2016-02-01

    One objective of the "Ocean Autonomous Observation" team of the Laboratory of Oceanography of Villefranche-sur-mer is to develop new means to outreach our science activities to various audiences. Besides the scientific community, this includes students and targets the general public, school pupils, and stakeholders. In this context, we have acquired a digital video globe with tactile capabilities and we will present here the various applications that we have been developing. A first type of products concerns the visualization of oceanic properties (SST, salinity, density, Chla, O2, NO3, irradiance) by diving from the surface (generally from satellite data) into the Ocean interior (through the use of global data bases, Argo, WOA). In second place, specific applications deal with surface animations allowing highlighting the seasonality of some properties (Chla, SST, ice cover, currents; based on satellite as well as modeling outputs). Finally, we show a variety of applications developed using the tactile functionality of the spherical display. In particular real-time vertical profiles acquired by Bio-Argo floats become directly accessible for the entire open ocean. Such a new tool plus its novel applications has been presented to school children, and to the wider public (at the so-called "fête de la science") as well as to potential sponsors of our science-outreach activities. Their feedback has always been highly positive and encouraging in terms of impact. From the scientists point of view, the use of this new support can easily compete with the classical PowerPoint, is much more attractive and fun and undeniably helps to outreach the various aspects of our pluridisciplinary science.

  18. Enhancing Oceanography Classrooms with "Captive and Cultured" Ocean Experiences

    Science.gov (United States)

    Macko, S. A.; Tuite, M.; O'Connell, M.

    2012-04-01

    Students in oceanography classes often request more direct exposure to actual ocean situations or field trips. During regular session (13 week) or shorter term (4 week) summer classes such long trips are logistically difficult owing to large numbers of students involved or timing. This new approach to such a course supplement addresses the requests by utilizing local resources and short field trips for a limited number of students (20) to locations in which Ocean experiences are available, and are often supported through education and outreach components. The vision of the class was a mixture of classroom time, readings, along with paper and actual laboratories. In addition short day-long trips to locations where the ocean was "captured" were also used to supplement the experience as well as speakers involved with aquaculture ("cultivated") . Central Virginia is a fortunate location for such a class, with close access for "day travel" to the Chesapeake Bay and numerous field stations, museums with ocean-based exhibits (the Smithsonian and National Zoo) that address both extant and extinct Earth history, as well as national/state aquaria in Baltimore, Washington and Virginia Beach. Furthermore, visits to local seafood markets at local grocery stores, or larger city markets) enhance the exposure to productivity in the ocean, and viability of the fisheries sustainability. The course could then address not only the particulars of the marine science, but also aspects of ethics, including keeping animals in captivity or overfishing of particular species and the special difficulties that arise from captive or culturing ocean populations. In addition, the class was encouraged to post web-based journals of experiences in order to share opinions of observations in each of the settings.

  19. PROJECT BLUE: An Operational Oceanography program in the Southeastern Brazil.

    Science.gov (United States)

    Alves dos Santos, Francisco; da Rocha Fragoso, Maurício; Maturo Marques da Cruz, Leonardo; de Castro Pellegrini, Julio Augusto; de Freitas Assad, Luiz Paulo; Landau, Luiz; Adissi, Flávia

    2013-04-01

    The beginning of 2013 will mark the start for the Project BLUE, one of the greatest efforts in operational oceanography ever proposed in Brazil. The region of interest is located in the continental shelf break between Cabo Frio (23°S) and Floriananópolis Island (28°S). The region is dominated by the Brazil Current system, formed by the Brazil Current, carrying Tropical Water southward from surface down to 400-500 meters and the Intermediate Counter Current, flowing northward in the interface of the South Atlantic Central Water and the Antarctic Intermediate Water. In situ data and operational forecasts efforts in this oil rich region are still few and disperse. Nevertheless, the constant increase of offshore operations is followed by the necessity of both a baseline study and a systematic data collection. All project structure is aimed at optimizing real-time data collection and displaying. Project BLUE is formed by 4 modules: (1) In situ data collection will be performed by 5 gliders, 108 surface drifters and 36 subsurface profiling floats. (2) Remote Sensing module count on a local receiving antenna to provide operational information of Sea Surface Temperature, Height and Ocean Color. (3) Numerical Modelling module aims, initially, to implement a regional grid for long climatological runs, followed by an operational run, with assimilation of the data generated by the first module. One of the great concerns of the Project BLUE is to turn public all collected data, allowing for a greater number of researchers to access the data and, consequently, improving the knowledge on the region. For that purpose, there is an specific module (4) Data displaying focused on easing the access to the data via web services. It is expected, by the end of the first three years, to have a systematic data collection system, a well adapted assimilation scheme and an operational forecast model for the Santos Basin, providing reliable information for offshore operations and emergency

  20. Acoustic Wave Scattering from a Random Ocean Bottom

    Science.gov (United States)

    1991-06-01

    there are researchers who model the rough ocean bottom as fractals [33,34,35,36,37]. One major advantage of this approach is that if the rough boundary...is indeed fractal , the self-similar property of the fractal will enable us to just measure the statistics of the roughness at one scale and predict...Acoustical Oceanography, John Wiley and Sons, New York (1977). [2] J. P. Kennett, Marine Geology , Prentice-Hall (1982). [3] C. Eckart, "The scattering of

  1. Acoustic emission

    International Nuclear Information System (INIS)

    Straus, A.; Lopez Pumarega, M.I.; Di Gaetano, J.O.; D'Atellis, C.E.; Ruzzante, J.E.

    1990-01-01

    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)

  2. Acoustic emission

    Indian Academy of Sciences (India)

    3Universidade do Minho, Department Engineering Mecânica, Azurém,. 4800058 Guimar˜aes, Portugal e-mail: mathew@dem.uminho.pt. Abstract. Acoustic Emission (AE) has been widely used for monitoring man- ufacturing processes particularly those involving metal cutting. Monitoring the condition of the cutting tool in the ...

  3. Strategies for Assessing Learning Outcomes in an Online Oceanography Course

    Science.gov (United States)

    Reed, D. L.

    2003-12-01

    All general education courses at the San Jose State University, including those in the sciences, must present a detailed assessment plan of student learning, prior to certification for offering. The assessment plan must state a clear methodology for acquiring data on student achievement of the learning outcomes for the specific course category, as well as demonstrate how students fulfill a strong writing requirement. For example, an online course in oceanography falls into the Area R category, the Earth and Environment, through which a student should be able to demonstrate an understanding of the methods and limits of scientific investigation; distinguish science from pseudo-science; and apply a scientific approach to answer questions about the Earth and environment. The desired learning outcomes are shared with students at the beginning of the course and subsequent assessments on achieving each outcome are embedded in the graded assignments, which include a critical thinking essay, mid-term exam, poster presentation in a symposium-style format, portfolio of web-based work, weekly discussions on an electronic bulletin board, and a take-home final exam, consisting of an original research grant proposal. The diverse nature of the graded assignments assures a comprehensive assessment of student learning from a variety of perspectives, such as quantitative, qualitative, and analytical. Formative assessment is also leveraged into learning opportunities, which students use to identify the acquisition of knowledge. For example, pre-tests are used to highlight preconceptions at the beginning of specific field studies and post-testing encourages students to present the results of small research projects. On a broader scale, the assessment results contradict common misperceptions of online and hybrid courses. Student demand for online courses is very high due to the self-paced nature of learning. Rates of enrollment attrition match those of classroom sections, if students

  4. A Retrospective Self-Assessment of the SURFO Summer Internship Program in Oceanography

    Science.gov (United States)

    Pockalny, R. A.; Donohue, K. A.; Fliegler, J.

    2009-12-01

    The Summer Undergraduate Research Fellowships in Oceanography (SURFO) program at the Graduate School of Oceanography/University of Rhode Island is an NSF-funded Research Experience for Undergraduates site program with a programmatic research niche focused on quantitative aspects of Oceanography. Each summer-cohort includes 9-12 participants (rising seniors) who are paired with a primary research advisor and often with a graduate student mentor. The primary components of the 10-week program include a 4-week introductory phase and a 6-week core research phase. A retrospective self-assessment instrument gauged the confidence, attitude and comfort level of participants with; 1) core math and science subjects, 2) oceanography-related subjects, 3) research skills, and 4) SURFO and GSO staff. SURFO participants evaluated themselves at the start of the program, after the introductory phase, and at the end of the program. Participants were also asked to reassess their initial evaluations and provide an updated score. The pre-assessment results indicate that the program recruits students from the target group (e.g., strong physics and math backgrounds, but with limited exposure to oceanography). The results also indicate that the students are initially comfortable with their advising team, but not so comfortable with their research topic and research skills. The post-introductory phase results indicate large increases in comfort level with the advising team and the local research community yet little or no change is indicated for research skills. The final assessments show large changes in oceanography-content knowledge, research topic, and research skills. The retrospective reassessment indicates an initial overconfidence in most categories. Overall, the largest changes occurred during the core research portion of the program. These results reinforce the importance/effectiveness of authentic, hands-on, inquiry-based research for higher learning and training the next

  5. Utilizing social media for informal ocean conservation and education: The BioOceanography Project

    Science.gov (United States)

    Payette, J.

    2016-02-01

    Science communication through the use of social media is a rapidly evolving and growing pursuit in academic and scientific circles. Online tools and social media are being used in not only scientific communication but also scientific publication, education, and outreach. Standards and usage of social media as well as other online tools for communication, networking, outreach, and publication are always in development. Caution and a conservative attitude towards these novel "Science 2.0" tools is understandable because of their rapidly changing nature and the lack of professional standards for using them. However there are some key benefits and unique ways social media, online systems, and other Open or Open Source technologies, software, and "Science 2.0" tools can be utilized for academic purposes such as education and outreach. Diverse efforts for ocean conservation and education will continue to utilize social media for a variety of purposes. The BioOceanography project is an informal communication, education, outreach, and conservation initiative created for enhancing knowledge related to Oceanography and Marine Science with an unbiased yet conservation-minded approach and in an Open Source format. The BioOceanography project is ongoing and still evolving, but has already contributed to ocean education and conservation communication in key ways through a concerted web presence since 2013, including a curated Twitter account @_Oceanography and BioOceanography blog style website. Social media tools like those used in this project, if used properly can be highly effective and valuable for encouraging students, networking with researchers, and educating the general public in Oceanography.

  6. Acoustic Interactions with the Endangered Vaquita

    OpenAIRE

    Lande, Michelle

    2009-01-01

    The vaquita (Phocoena sinus) are endemic to the northernmost portion of the Gulf of California and are the world’s most endangered cetacean. Vaquita, like other toothed whales, have the ability to echolocate, which is the use of biological sonar to investigate their environment. Acoustics allow scientists to study these animals’ behavior, biology, and population dynamics more easily. This project aimed to use Finite Element Modeling (FEM) to understand the interaction between acoustic stimuli...

  7. Acoustic detection

    International Nuclear Information System (INIS)

    Riccobene, Giorgio

    2008-01-01

    The proposal of acoustic neutrino detection is living a renaissance: the interest in ultra high energy neutrino detection, the fast improvements of deep sea technology and the availability of large deep sea research infrastructures are the three main ingredients to explain the new interest in this technique. The status of simulation work, medium studies, sensor developments and first results from test experimental setups are presented.

  8. Acoustic Territoriality

    DEFF Research Database (Denmark)

    Kreutzfeldt, Jacob

    2011-01-01

    Under the heading of "Gang i København" a number of initiatives was presented by the Lord Mayer and the Technical and Environmental Mayer of Copenhagen in May 2006. The aim of the initiative, which roughly translates to Lively Copenhagen, was both to make Copenhagen a livelier city in terms of ci...... this article outline a few approaches to a theory of acoustic territoriality....

  9. Advances in Oceanography and Limnology - Themed Issue - Cyanobacteria

    Czech Academy of Sciences Publication Activity Database

    Babica, Pavel (ed.); Capelli, C. (ed.); Drobac, D. (ed.); Gkelis, S. (ed.)

    2017-01-01

    Roč. 8, č. 1 (2017), s. 1-178 ISSN 1947-573X Institutional support: RVO:67985939 Keywords : cyanobacteria l water blooms * cyanobacteria l water blooms * cyanobacteria Subject RIV: DJ - Water Pollution ; Quality OBOR OECD: Marine biology, freshwater biology, limnology http://pagepressjournals.org/index.php/aiol/issue/view/460

  10. Acoustic lenses

    International Nuclear Information System (INIS)

    Kittmer, C.A.

    1983-03-01

    Acoustic lenses focus ultrasound to produce pencil-like beams with reduced near fields. When fitted to conventional (flat-faced) transducers, such lenses greatly improve the ability to detect and size defects. This paper describes a program developed to design acoustic lenses for use in immersion or contact inspection, using normal or angle beam mode with flat or curved targets. Lens surfaces are circular in geometry to facilitate machining. For normal beam inspection of flat plate, spherical or cylindrical lenses are used. For angle beam or curved surface inspections, a compound lens is required to correct for the extra induced aberration. Such a lens is aspherical with one radius of curvature in the plane of incidence, and a different radius of curvature in the plane perpendicular to the incident plane. The resultant beam profile (i.e., location of the acoustic focus, beam diameter, 6 dB working range) depends on the degree of focusing and the transducer used. The operating frequency and bandwidth can be affected by the instrumentation used. Theoretical and measured beam profiles are in good agreement. Various applications, from zone focusing used for defect sizing in thick plate, to line focusing for pipe weld inspection, are discussed

  11. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Learn Back Learn about acoustic neuroma AN Facts What is acoustic neuroma? Diagnosing Symptoms Side Effects Keywords ... patient kit Treatment Options Overview Observation Radiation Surgery What is acoustic neuroma Diagnosing Symptoms Side effects Question ...

  12. Marine Acoustic Sensor Assembly

    National Research Council Canada - National Science Library

    Ruffa, Anthony A

    2007-01-01

    A marine acoustic sensor assembly includes an acoustic panel having a forward surface and an after surface, a laser scanner oriented so as to project a laser beam onto the acoustic panel after surface...

  13. A Novel Empirical Orthogonal Function (EOF)-Based Methodology to Study the Internal Wave Effects on Acoustic Propagation

    Science.gov (United States)

    2011-10-01

    mail: gaelle.casagrande@dga.defense.gouv.fr). Y. Stephan is with the Service Hydrographique et Oceanographique de la Marine (SHOM), Brest 29200...640-653, 2002. ^«^^^ Gaelic Casagrande received the M.Se. degree in ^m Ik ph\\sies from the University Paul Sabatier, Toulouse, fl ^k France...Marine (SHOM) within the Military Oceanography Depart- ment, Brest , France. His current interests include acoustic environmental assessment and

  14. Oceanography of the Grand Banks Region of Newfoundland, March 1974 - October 1974.

    Science.gov (United States)

    1978-07-01

    andwin cotro drft f cebrgsandconideed (Smith, 1931; Budinger, 1960; Kollmeyer, 1965; the primary forces responsible for iceberg drift and Ettle , 1974...unpublished manuscript). Oceanography of the New York Bight, August 1974. Ettle , Robert E. (1974). Statistical Analysis of Observec U.S. Coast Guard

  15. Ranking serials in oceanography: An analysis based on the Indian contributions and their citations

    Digital Repository Service at National Institute of Oceanography (India)

    Tapaswi, M.P.; Maheswarappa, B.S.

    in oceanography is noticed. The contributions to Indian serials showed a decrease. The implications of this trend are discussed. The rank list of serials cited by Indian oceanographers was correlated with the rank list of serials cited at international level. A...

  16. Research and Teaching: Implementation of Interactive Engagement Teaching Methods in a Physical Oceanography Course

    Science.gov (United States)

    Keiner, Louis E.; Gilman, Craig

    2015-01-01

    This study measures the effects of increased faculty-student engagement on student learning, success rates, and perceptions in a Physical Oceanography course. The study separately implemented two teaching methods that had been shown to be successful in a different discipline, introductory physics. These methods were the use of interactive…

  17. Preface: Special Issue of the 5th International Symposium on Biological and Environmental Chemistry of DMS(P) and Related Compounds, Goa, India, 19–22 October 2010

    Digital Repository Service at National Institute of Oceanography (India)

    Stefels, J.; Shenoy, D.M.; Simo, R.; Malin, G.; Levasseur, M.; Belviso, S.; DileepKumar, M.

    This Special Issue of Biogeochemistry contains a selection of papers presented at the 5th International Symposium on Biological and Environmental Chemistry of DMS(P) and Related Compounds, organized at the National Institute of Oceanography (NIO...

  18. Acoustic data - Integrated acoustic and trawl survey of Pacific hake off the Pacific Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Integrated acoustic and trawl surveys are used to assess the distribution, biomass, and biology of Pacific hake along the Pacific coasts of the United States and...

  19. West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume II. Physical and chemical oceanography. Final report

    Energy Technology Data Exchange (ETDEWEB)

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)

    1983-02-01

    This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which is located in southwestern Louisiana, and which is designed to store 241 million barrels of crude oil. Oil storage caverns are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. Contents of Volume II include: introduction; physical oceanography; estuarine hydrology and hydrography; analysis of discharge plume; and water and sediment quality.

  20. Biological oceanography across the Southern Indian Ocean – basinscale trends in the zooplankton community

    DEFF Research Database (Denmark)

    Jonasdottir, Sigrun; Nielsen, Torkel Gissel; Borg, Christian Marc Andersen

    2013-01-01

    We present a study on the protozooplankton 45 mm and copepods larger than 50 mm at a series of contrasting stations across the Southern Indian Ocean (SIO). Numerically, over 80% of the copepod community across the transect was less than 650 mm in size, dominated by nauplii, and smaller copepods...

  1. Arctic data compilation and appraisal. Vol. 10, Beaufort Sea: Biological oceanography - whales 1848 to 1983

    Energy Technology Data Exchange (ETDEWEB)

    Norton, P.; Smiley, B.D.; de March, L.

    1987-01-01

    This data report is an inventory of measurements and observations of white whales, bowhead whales, gray whales, harbour porpoises, narwhal, and killer whales in the Beaufort Sea and Amundsen Gulf. Measurements most commonly reported concern numbers, identification, movements, morphometrics, age behaviour, food, and reproduction. Organization within this inventory is by data set (measurements and observations made by one group of people, for a particular purpose, generally within one year). In all, 143 data sets were inventoried for the 1848 to 1983 period. Times and locations of sampling efforts are listed in tables and also are shown on computer-drawn maps. Sampling methodology and intensity, whale measurements and observations obtained by species, and concurrent bio logical, physical, and chemical measurements are described in the tables. A five-level rating system, based on sampling methodolgy, is outlined and has been applied to each measurement in each data set as a rough indication of the data's reliability. Data sets are indexed according to geographic coverage, study methods, species, measurements and observations made by category, and published references. The form, location, and availability of original data is given if know. 74 refs 115 figs 3 tabs

  2. The Relationship Among Oceanography, Prey Fields, and Beaked Whale Foraging Habitat in the Tongue of the Ocean

    Science.gov (United States)

    2011-04-01

    D, McDonald M, Polovina J, Domokos R, Wiggins S, et al. (2008) Temporal patterns in the acoustic signals of beaked whales at Cross Seamount . Biology ...28,29,30]. A multi-directional bottom-mounted hydrophone was deployed at Cross seamount southwest of the Kona coast and found a high number of beaked whale...habitat- dependent resource utilisation by deep-sea fishes at the Great Meteor seamount : niche overlap and support for the sound scattering layer

  3. Parametric Room Acoustic Workflows

    DEFF Research Database (Denmark)

    Parigi, Dario; Svidt, Kjeld; Molin, Erik

    2017-01-01

    and interoperability with Grasshopper 3d. The focus will be placed to the benchmarking of three different acoustic analysis tools based on raytracing. To compare the accuracy and speed of the acoustic evaluation across different tools, a homogeneous set of acoustic parameters is chosen. The room acoustics parameters...

  4. Developing European operational oceanography for Blue Growth, climate change adaptation and mitigation, and ecosystem-based management

    Science.gov (United States)

    She, Jun; Allen, Icarus; Buch, Erik; Crise, Alessandro; Johannessen, Johnny A.; Le Traon, Pierre-Yves; Lips, Urmas; Nolan, Glenn; Pinardi, Nadia; Reißmann, Jan H.; Siddorn, John; Stanev, Emil; Wehde, Henning

    2016-07-01

    Operational approaches have been more and more widely developed and used for providing marine data and information services for different socio-economic sectors of the Blue Growth and to advance knowledge about the marine environment. The objective of operational oceanographic research is to develop and improve the efficiency, timeliness, robustness and product quality of this approach. This white paper aims to address key scientific challenges and research priorities for the development of operational oceanography in Europe for the next 5-10 years. Knowledge gaps and deficiencies are identified in relation to common scientific challenges in four EuroGOOS knowledge areas: European Ocean Observations, Modelling and Forecasting Technology, Coastal Operational Oceanography and Operational Ecology. The areas "European Ocean Observations" and "Modelling and Forecasting Technology" focus on the further advancement of the basic instruments and capacities for European operational oceanography, while "Coastal Operational Oceanography" and "Operational Ecology" aim at developing new operational approaches for the corresponding knowledge areas.

  5. Proceedings of a workshop on physical oceanography related to the subseabed disposal of high-level nuclear waste

    International Nuclear Information System (INIS)

    Marietta, M.G.

    1981-04-01

    At this workshop a group of expert scientists: (1) assessed the current state of knowledge with regard to the physical oceanographic questions that must be answered generally if high level nuclear waste is to be disposed of on or under the seabed; (2) discussed physical oceanographic science necessarily related to the US Subseabed Disposal Program; (3) recommended necessary research; and (4) identified other ongoing programs with which important liaisons should be made and continued. This report is a collection of workshop presentations, and recommendations, and a synthesis of topical group recommendations into a unified statement of research needs. The US Seabed Disposal Program is described. The goal is to assess the technical, environmental and engineering feasibility of seabed disposal. The environmental studies program will assess possible ecosystem and health effects from radionuclides which may be released due to accidental leakage. Discussion on the following topics are also included: bottom boundary layer; mixing across isopycnal surfaces; circulation modeling; mesoscale dispersion; deep circulation of the Pacific Ocean; vertical transport at edges; instrumentation; chemical oceanography; plutonium distribution in the Pacific; biology report; chemical dumping report; and low-level waste report

  6. Data analysis methods in physical oceanography. By Emery, W.J. and Thomson, R.E.

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, M.R.

    and practical compilation of the essential information and analysis techniques required for the advanced processing and interpretation of digital spatio-temporal data in physical oceanography, as well as in other branches of the geophysical sciences. The book... assumes a fundamental understanding of calculus and is directed primarily towards scientists and engineers in the industry, government and universities, including graduate and advanced undergraduate students. Spanning five chapters and numerous...

  7. Oceanography - High Frequency Radar and Ocean Thin Layers, Volume 10, No. 2

    Science.gov (United States)

    1999-03-11

    1975: The dissolved gases- carbon dioxide . In: Chemical Oceanography, vol. 2, 2nd edition. J.P. Riley and G. Skirrow, eds.. Academic Press. New York, 1...A similar radar was used by the Institut Francais du Petrole in the Shetland Islands (Shearman, 1983). A mul- tifrequency radar constructed at...plied to small- footprint , direction-finding systems. The same techniques can be applied to algorithms used with beam-forming systems (e.g., Barrick

  8. The Pale Blue Dot: Utilizing Real World Globes in High School and Undergraduate Oceanography Classrooms

    Science.gov (United States)

    Rogers, D. B.

    2017-12-01

    Geoscience classrooms have benefitted greatly from the use of interactive, dry-erasable globes to supplement instruction on topics that require three-dimensional visualization, such as seismic wave propagation and the large-scale movements of tectonic plates. Indeed, research by Bamford (2013) demonstrates that using three-dimensional visualization to illustrate complex processes enhances student comprehension. While some geoscience courses tend to bake-in lessons on visualization, other disciplines of earth science that require three-dimensional visualization, such as oceanography, tend to rely on students' prior spatial abilities. In addition to spatial intelligence, education on the three-dimensional structure of the ocean requires knowledge of the external processes govern the behavior of the ocean, as well as the vertical and lateral distribution of water properties around the globe. Presented here are two oceanographic activities that utilize RealWorldGlobes' dry-erase globes to supplement traditional oceanography lessons on thermohaline and surface ocean circulation. While simultaneously promoting basic plotting techniques, mathematical calculations, and unit conversions, these activities touch on the processes that govern global ocean circulation, the principles of radiocarbon dating, and the various patterns exhibited by surface ocean currents. These activities challenge students to recognize inherent patterns within their data and synthesize explanations for their occurrence. Spatial visualization and critical thinking are integral to any geoscience education, and the combination of these abilities with engaging hands-on activities has the potential to greatly enhance oceanography education in both secondary and postsecondary settings

  9. 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....

  10. 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...

  11. 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.

  12. 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...... 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....

  13. Acoustics an introduction

    CERN Document Server

    Kuttruff, Heinrich

    2006-01-01

    This definitive textbook provides students with a comprehensive introduction to acoustics. Beginning with the basic physical ideas, Acoustics balances the fundamentals with engineering aspects, applications and electroacoustics, also covering music, speech and the properties of human hearing. The concepts of acoustics are exposed and applied in:room acousticssound insulation in buildingsnoise controlunderwater sound and ultrasoundScientifically thorough, but with mathematics kept to a minimum, Acoustics is the perfect introduction to acoustics for students at any level of mechanical, electrical or civil engineering courses and an accessible resource for architects, musicians or sound engineers requiring a technical understanding of acoustics and their applications.

  14. Acoustic Holography

    Science.gov (United States)

    Kim, Yang-Hann

    One of the subtle problems that make noise control difficult for engineers is the invisibility of noise or sound. A visual image of noise often helps to determine an appropriate means for noise control. There have been many attempts to fulfill this rather challenging objective. Theoretical (or numerical) means for visualizing the sound field have been attempted, and as a result, a great deal of progress has been made. However, most of these numerical methods are not quite ready for practical applications to noise control problems. In the meantime, rapid progress with instrumentation has made it possible to use multiple microphones and fast signal-processing systems. Although these systems are not perfect, they are useful. A state-of-the-art system has recently become available, but it still has many problematic issues; for example, how can one implement the visualized noise field. The constructed noise or sound picture always consists of bias and random errors, and consequently, it is often difficult to determine the origin of the noise and the spatial distribution of the noise field. Section 26.2 of this chapter introduces a brief history, which is associated with sound visualization, acoustic source identification methods and what has been accomplished with a line or surface array. Section 26.2.3 introduces difficulties and recent studies, including de-Dopplerization and de-re verberation methods, both essential for visualizing a moving noise source, such as occurs for cars or trains. This section also addresses what produces ambiguity in realizing real sound sources in a room or closed space. Another major issue associated with sound/noise visualization is whether or not we can distinguish between mutual dependencies of noise in space (Sect. 26.2.4); for example, we are asked to answer the question, Can we see two birds singing or one bird with two beaks?

  15. The Oceanography and Ecology of the Ross Sea

    Science.gov (United States)

    Smith, Walker O.; Ainley, David G.; Arrigo, Kevin R.; Dinniman, Michael S.

    2014-01-01

    The continental shelf of the Ross Sea exhibits substantial variations in physical forcing, ice cover, and biological processes on a variety of time and space scales. Its circulation is characterized by advective inputs from the east and exchanges with off-shelf regions via the troughs along the northern portions. Phytoplankton biomass is greater there than anywhere else in the Antarctic, although nitrate is rarely reduced to levels below 10 μmol L-1. Overall growth is regulated by irradiance (via ice at the surface and by the depths of the mixed layers) and iron concentrations. Apex predators reach exceptional abundances, and the world's largest colonies of Adélie and emperor penguins are found there. Krill are represented by two species (Euphausia superba near the shelf break and Euphausia crystallorophias throughout the continental shelf region). Equally important and poorly known is the Antarctic silverfish (Pleuragramma antarcticum), which is also consumed by most upper-trophic-level predators. Future changes in the Ross Sea environment will have profound and unpredictable effects on the food web.

  16. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Facts What is acoustic neuroma? Diagnosing Symptoms Side Effects Keywords Questions to ask Choosing a healthcare provider ... Surgery What is acoustic neuroma Diagnosing Symptoms Side effects Question To Ask Treatment Options Back Overview Observation ...

  17. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... more... LOGIN CALENDAR DONATE NEWS Home Learn Back Learn about acoustic neuroma AN Facts What is acoustic ... Stories Keywords Shop ANA Discussion Forum About Back Learn more about ANA About ANA Mission, Vision & Values ...

  18. 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 underwater...

  19. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... more Click to learn more... LOGIN CALENDAR DONATE NEWS Home Learn Back Learn about acoustic neuroma AN ... a Sponsor Patient Events Acoustic Neuroma Association Latest News Join / Renew Login Contact Us Become a Sponsor ...

  20. Priorities and developments of sensors, samplers and methods for key marine biological observations.

    Science.gov (United States)

    Simmons, Samantha; Chavez, Francisco; Pearlman, Jay

    2016-04-01

    Over the last two decades or more, physical oceanography has seen a significant growth in in-situ sensors and platforms including fixed point and cable observatories, Argo floats, gliders and AUVs to supplement satellites for creating a 3-D view of the time-varying global ocean temperature and salinity structures. There are important developments recently for biogeochemists for monitoring nitrate, chemical contaminants, oxygen and pH that can now be added to these autonomous systems. Biologists are still lagging. Given the importance of biology to ocean health and the future earth, and the present reliance on humans and ships for observing species and abundance, it is paramount that new biological sensor systems be developed. Some promising sensor systems based on, but not limited to acoustic, chemical, genomic or imaging techniques, can sense from microbes to whales, are on the horizon. These techniques can be applied in situ with either real time or recorded data and can be captured and returned to the laboratory using the autonomous systems. The number of samples is limiting, requiring adaptive and smart systems. Two steps are envisioned to meeting the challenges. The first is to identify the priority biological variables to focus observation requirements and planning. The second is to address new sensors that can fill the gaps in current capabilities for biological observations. This abstract will review recent efforts to identify core biological variables for the US Integrated Ocean Observing System and address new sensors and innovations for observing these variables, particularly focused on availability and maturity of sensors.

  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. Highly Localized Acoustic Streaming and Size-Selective Submicrometer Particle Concentration Using High Frequency Microscale Focused Acoustic Fields.

    Science.gov (United States)

    Collins, David J; Ma, Zhichao; Ai, Ye

    2016-05-17

    Concentration and separation of particles and biological specimens are fundamental functions of micro/nanofluidic systems. Acoustic streaming is an effective and biocompatible way to create rapid microscale fluid motion and induce particle capture, though the >100 MHz frequencies required to directly generate acoustic body forces on the microscale have traditionally been difficult to generate and localize in a way that is amenable to efficient generation of streaming. Moreover, acoustic, hydrodynamic, and electrical forces as typically applied have difficulty manipulating specimens in the submicrometer regime. In this work, we introduce highly focused traveling surface acoustic waves (SAW) at high frequencies between 193 and 636 MHz for efficient and highly localized production of acoustic streaming vortices on microfluidic length scales. Concentration occurs via a novel mechanism, whereby the combined acoustic radiation and streaming field results in size-selective aggregation in fluid streamlines in the vicinity of a high-amplitude acoustic beam, as opposed to previous acoustic radiation induced particle concentration where objects typically migrate toward minimum pressure locations. Though the acoustic streaming is induced by a traveling wave, we are able to manipulate particles an order of magnitude smaller than possible using the traveling wave force alone. We experimentally and theoretically examine the range of particle sizes that can be captured in fluid streamlines using this technique, with rapid particle concentration demonstrated down to 300 nm diameters. We also demonstrate that locations of trapping and concentration are size-dependent, which is attributed to the combined effects of the acoustic streaming and acoustic forces.

  3. Late winter oceanography off the Sabrina and BANZARE coast (117-128°E), East Antarctica

    Science.gov (United States)

    Williams, G. D.; Meijers, A. J. S.; Poole, A.; Mathiot, P.; Tamura, T.; Klocker, A.

    2011-05-01

    We report on the late winter oceanography observed beneath the Antarctic sea ice offshore from the Sabrina and BANZARE coast of Wilkes Land, East Antarctica (117-128°E) in September-October 2007 during the Sea Ice Physics and Ecosystem eXperiment (SIPEX). A pilot program using specifically designed 'through-ice' conductivity-temperature-depth (CTD) and acoustic Doppler current profiling (ADCP) systems was conducted to opportunistically measure water mass properties and ocean currents at major ice stations. Additional water mass properties across the survey region were collected from Ice-Argo floats deployed during the voyage north of the 3000 m isobath. The mean drift of the floats was along the slope to the west with the Antarctic Slope Current. Vertical profiles of the potential temperature reveal the deepest (˜350-400m) winter mixed layer (WML) in the western sector of the survey northwest of the Dalton Iceberg Tongue polynya. The meridional structure of the Antarctic Slope Front, i.e. the monotonic shoaling of the WML across the upper continental slope, is found to be similar to the previous observations in summer. A strong bottom-intensified intrusion of modified Circumpolar Deep Water (mCDW) as warm as 0 °C was detected beneath the fast ice south of the continental shelf break at 118°E. An mCDW intrusion of similar strength was detected near this location in the austral summer of 1996. We hypothesise that there is a persistent supply of mCDW and associated ocean heat flux to this region of the continental shelf that is capable of migrating to the grounding lines of the nearby Totten Glacier and Moscow University Ice Shelf. There was no detection of locally formed dense shelf water capable of forming Antarctic Bottom Water at the shelf break locations sampled despite the number of minor polynyas across this region. Ocean current measurements, limited to a maximum period of 24 h and 50-100 m depth by the relative scarcity of backscatter, found increased

  4. Principles and effects of acoustic cavitation - A review

    Directory of Open Access Journals (Sweden)

    Corina GÂMBUŢEANU

    2013-12-01

    Full Text Available In the recent years, food industry has shown a real interest in ultrasound use because of its effect on physical, biochemical and microbial properties of food systems. In order to better understand how the acoustic cavity effects could be best applied in food industry, a review on acoustic cavitation and its effects was done. The present paper describes in detail the basic principles underlying the effects of ultrasounds on food processing applications. It also provides theoretical background on acoustic cavitation and ultrasound production method. Moreover, harnessing mechanic, optic, chemical and biological effects of acoustic cavitation in food industry were briefly highlighted.

  5. The Indigo V Indian Ocean Expedition: a prototype for citizen microbial oceanography

    DEFF Research Database (Denmark)

    Lauro, Frederico; Senstius, Svend Jacob; Cullen, Jay

    2014-01-01

    Microbial Oceanography has long been an extremely expensive discipline, requiring ship time for sample collection and thereby economically constraining the number of samples collected. This is especially true for under-sampled water bodies such as the Indian Ocean. Specialised scientific equipment...... only adds to the costs.Moreover, long term monitoring of microbial communities and large scale modelling of global biogeochemical cycles requires the collection of high-density data both temporally and spatially in a cost-effective way. Thousands of private ocean-going vessels are cruising around...

  6. Arabian Sea oceanography and fisheries of the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Madhupratap, M.; Nair, K.N.V.; Gopalakrishnan, T.C.; Haridas, P.; Nair, K.K.C.; Venugopal, P.; Gauns, M.

    of poten tial fishery resources from the E x- clusive Economic Zone of India (EEZ) are about 3.5 to 4.7 mt (million tonnes) 1 ? 4 . The recent estimates on a n- nual marine landings from the I n dian coast show that they fluctuate between 2.2 and 2... given by the Central Marine Fis h eries Research Institute (CMFRI) 5 for the period 1985 ? 1993. General oceanography and the lower food c hain Based on the atmospheric forcing, the seasonality in the Arabian Sea could be clearly defined...

  7. Streaming and particle motion in acoustically-actuated leaky systems

    Science.gov (United States)

    Nama, Nitesh; Barnkob, Rune; Jun Huang, Tony; Kahler, Christian; Costanzo, Francesco

    2017-11-01

    The integration of acoustics with microfluidics has shown great promise for applications within biology, chemistry, and medicine. A commonly employed system to achieve this integration consists of a fluid-filled, polymer-walled microchannel that is acoustically actuated via standing surface acoustic waves. However, despite significant experimental advancements, the precise physical understanding of such systems remains a work in progress. In this work, we investigate the nature of acoustic fields that are setup inside the microchannel as well as the fundamental driving mechanism governing the fluid and particle motion in these systems. We provide an experimental benchmark using state-of-art 3D measurements of fluid and particle motion and present a Lagrangian velocity based temporal multiscale numerical framework to explain the experimental observations. Following verification and validation, we employ our numerical model to reveal the presence of a pseudo-standing acoustic wave that drives the acoustic streaming and particle motion in these systems.

  8. Geophysics, Oceanography

    Science.gov (United States)

    Halpern, D.; Wentz, F.

    1993-01-01

    Development of decade-long time series of global surface wind measurements for studies ofseasonal-to-interannual climate variability presents unique challenges for space- borne instrumentationbecause of the necessity to combine data sets of 3- to 5-year lifetimes. Before the first Special SensorMicrowave Imager (SSMI), which was launched on the Defence Meteorological Satellite Program(DMSP) F8 spacecraft in July 1987, stopped recording wind speed in December 1991, another SSMIwas launched on DMSP F10 in December 1991. Interpretation of the 1987 - 1993 composite timeseries is dependent upon the space and time characteristics of the differences between concurrent F8and F10 SSMI measurements. This paper emphasizes large geographical regions and 1-month timescale. The F8-F10 area-weighted difference between 60 degrees S and 60 degrees S during 305 daysof 1991 (-0.12 m s^(-1)) was comparable to the year-to-year wind speed variations during 1988-1991. The 10 degree-zonal averaged monthly mean F8-F10 difference was negative (positive) forwind speeds less (greater) than 7.9 m s^(-1), reaching - 0.43(0.32) m s^(-1) at 5(10) m s^(-1). The10 degree-zonal averaged monthly mean F8-F10 bias had considerable variations throughout the yearand between 60 degrees S - 60 degrees N, with the largest temporal variation (1.4 m s^(-1)) in the 50degrees - 60 degrees N region from February to April. The 1991 average value of the monthly meanroot-mean-square (rms) difference between F8 and F10 daily wind speeds in 10 degree-longitudinalbands was 2.0 m s^(-1) over 60 degrees S - 60 degrees N, the amplitude of the annual cycle of therms difference was largest in the northern hemisphere middle latitudes, and the rms difference wasrelated to the wind speed (e.g., at 6 and 10 m s^(-1), the rms difference was 1.7 and 2.7 m s^(-1),respectively). The relationship between monthly mean 1/3 degrees x 1/3 degrees F8-F10 SSMI windspeed differences and integrated water vapor and liquid water content in the atmosphere is discussed.

  9. Chemical oceanography

    National Research Council Canada - National Science Library

    Millero, F.J

    1996-01-01

    .... Based on courses taught over a ten-year period at the University of Miami, the book presents useful information for oceanographers and other marine scientists, in addition to providing a solid...

  10. Chemical oceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A

    have little effect on the cycles of major elements, except carbon and calcium, they greatly modify transformations of minor constituents. A hydrochemical discontinuity at approx. 10 degrees S latitude separates the low oxygen - high nutrients waters...

  11. Real-Time Access to Altimetry and Operational Oceanography Products via OPeNDAP/LAS Technologies : the Example of Aviso, Mercator and Mersea Projects

    Science.gov (United States)

    Baudel, S.; Blanc, F.; Jolibois, T.; Rosmorduc, V.

    2004-12-01

    project (June 2003 to June 2004) sponsored by the European Commission was the first experience of an integrated operational oceanography project. The objective was the assessment of several existing operational in situ and satellite monitoring and numerical forecasting systems for the future elaboration (Mersea Integrated Project, 2004-2008) of an integrated system able to deliver, operationally, information products (physical, chemical, biological) towards end-users in several domains related to environment, security and safety. Five forecasting ocean models with data assimilation coming from operational in situ or satellite data centres, have been intercompared. The main difficulty of this LAS implementation has lied in the ocean model metrics definition and a common file format adoption which forced the model teams to produce the same datasets in the same formats (NetCDF, COARDS/CF convention). Notice that this was a pioneer approach and that it has been adopted by Godae standards (see F. Blanc's paper in this session). Going on these web technologies implementation and entering a more user-oriented issue, perspectives deal with the implementation of a Map Server, a GIS opensource server which will communicate with the OPeNDAP server. The Map server will be able to manipulate simultaneously raster and vector multidisciplinary remote data. The aim is to construct a full complete web oceanic data distribution service. The projects in which we are involved allow us to progress towards that.

  12. Acoustic streaming in microchannels

    DEFF Research Database (Denmark)

    Tribler, Peter Muller

    This thesis presents studies of boundary-driven acoustic streaming in microfluidic channels, which is a steady flow of the fluid initiated by the interactions of an oscillating acoustic standing wave and the rigid walls of the microchannel. The studies present analysis of the acoustic resonance......, 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...... oscillating plates. Furthermore, under general thermodynamic conditions, we derive the time-dependent first- and second-order equations for the conservation of mass, momentum, and energy. The coupling from fluid equations to particle motion is achieved through the expressions for the streaming-induced drag...

  13. 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...

  14. 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...

  15. Deep Water Ocean Acoustics

    Science.gov (United States)

    2016-12-22

    analysis was conducted on the North Pacific Acoustics Laboratory Philippine Sea tests 2009 and 2010, both of which Dr. Heaney participated as a co-chief...obtained from the ambient noise field. In underwater acoustics , this travel time strongly depends on the depth and temperature and to a lesser extent...et al. 2012) and underwater volcanoes (Green at al. 2013). Guided wave propagation contributes to the limited acoustical attenuation by the SOFAR

  16. Strange Bedfellows; Physical and Biological Oceanographers

    Science.gov (United States)

    Wooster, W. S.

    2002-12-01

    When I started graduate study at Scripps in 1947, both the text, "The Oceans", and the curriculum - all students took the introductory courses in physics, chemistry, biology, and geology - conspired to create awareness of the interactions among these fields. In their preface, the authors spoke of the book as "an aid to the beginner and specialist alike in the coordination of the various fields of oceanography." Harald Sverdrup, perhaps the best known physical oceanographer of his day, introduced us to the interdisciplinary organization, ICES, wrote an important paper (1953) on "the vernal blooming of phytoplankton", and together with fishery biologist O.E.Sette, launched the world renowned CalCOFI program. Another noted physical oceanographer, Henry Stommel, 1949, teamed up with biologist Gordon Riley in a major study of the quantitative ecology of plankton. At the time, physical and biological oceanographers often seemed to be engaged in the same mission. The curriculum format, with its four basic courses, spread to most other graduate programs in oceanography, but the forces of specialization also spread. While the biological oceanographers have always seen the need to understand the milieu within which their creatures function, the physicists often seemed to chafe against wasting their time on squishy subjects like biology when there were so many more important and fascinating things to study. Interactions were further complicated by the confusion between "biological oceanography" and "marine biology", and by the status of "fishery biology" which was often disdained by oceanographers of all stripes. I propose to discuss the evolution of the relationship among these fields during the 60 years since "The Oceans" was first published, concluding with the present marriage of convenience, or at least amicable co-habitation, forced by the widespread concern over the threat of global warming and the need to understand its consequences. It has become clear that

  17. 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...

  18. 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...

  19. Acoustic Technology Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — This laboratory contains an electro-magnetic worldwide data collection and field measurement capability in the area of acoustic technology. Outfitted by NASA Langley...

  20. 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.

  1. 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.

  2. Laboratory for Structural Acoustics

    Data.gov (United States)

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

  3. The International System of Units (SI) in Oceanography. Report of IAPSO Working Group on Symbols, Units and Nomenclature in Physical Oceanography (SUN). Unesco Technical Papers in Marine Science 45. IAPSO Publication Scientifique No. 32.

    Science.gov (United States)

    United Nations Educational, Scientific, and Cultural Organization, Paris (France). Div. of Marine Sciences.

    This report introduces oceanographers to the International System of Units (SI) in physical oceanography. The SI constitutes a universal language, designed to be understood by all scientists. It facilitates their mutual comprehension and exchange of views and results of their work. The first part of the report is devoted to physical quantities,…

  4. Sailing for Science: on board experiences for transferring knowledge on Historical Oceanography for Future Innovation

    Science.gov (United States)

    Garvani, Sara; Carmisciano, Cosmo; Locritani, Marina; Grossi, Luigi; Mori, Anna; Stroobant, Mascha; Schierano, Erika; De Strobel, Federico; Manzella, Giuseppe; Muzi, Enrico; Leccese, Dario; Sinapi, Luigi; Morellato, Claudio; La Tassa, Hebert; Talamoni, Roberta; Coelho, Emanuel; Nacini, Francesca

    2017-04-01

    Smart, sustainable and inclusive Blue Growth means also knowing past technology and the paths followed by ancients in order to understand and monitor marine environments. In general, history of Science is a matter that is not enough explored and explained or promoted in high schools or university official programmes, and, usually, scientist do not consider it as an important part of their curricula. However, bad or good ideas, abandoned or forgotten beliefs, concepts, opinions, do still have a great potential for inspiring present and future scientists, no matter in which historical period they may have been formulated: they should be always be taken into consideration, critically examined and observed by a very close point of view, not just as part of the intellectual framework of some obsolete 'Cabinet of Curiosities' with limited access except for the chosen few. Moreover, history of Science should be transmitted in a more practical way, with hands-on labs showing the limits and challenges that prior generations of ocean explorers, investigators and seafarers had to face in order to answer to crucial questions as self-orientation in open sea, understanding main currents and waves, predicting meteorological conditions for a safe navigation. Oceanography is a relatively young branch of science, and still needs further approvals and knowledge (National Science Foundation, 2000). The Scientific Dissemination Group (SDG) "La Spezia Gulf of Science" - made up by Research Centres, Schools and Cultural associations located in La Spezia (Liguria, Italy) - has a decadal experience in initiatives aimed at people and groups of people of all ages, who are keen on science or who can be guided in any case to take an interest in scientific matters (Locritani et al., 2015). Amongst the SDG activities, the tight relationship with the Historical Oceanography Society, the Italian Navy and the Naval Technical Museum (that collects a rich heritage of civilization, technology and

  5. Science requirements for free-flying imaging radar (FIREX) experiment for sea ice, renewable resources, nonrenewable resources and oceanography

    Science.gov (United States)

    Carsey, F.

    1982-01-01

    A future bilateral SAR program was studied. The requirements supporting a SAR mission posed by science and operations in sea-ice-covered waters, oceanography, renewable resources, and nonrenewable resources are addressed. The instrument, mission, and program parameters were discussed. Research investigations supporting a SAR flight and the subsequent overall mission requirements and tradeoffs are summarized.

  6. Deep Water Ocean Acoustics

    Science.gov (United States)

    2015-07-17

    Ocean Acoustics 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER...paper and presented on global acoustic propagation (including on Europa, a small moon of Jupiter ) at the International Conference of Sound and

  7. Acoustic emission source modeling

    Czech Academy of Sciences Publication Activity Database

    Hora, Petr; Červená, Olga

    2010-01-01

    Roč. 4, č. 1 (2010), s. 25-36 ISSN 1802-680X R&D Projects: GA ČR GA101/09/1630 Institutional research plan: CEZ:AV0Z20760514 Keywords : acoustic emission source * wave propagation * FEM Subject RIV: BI - Acoustics

  8. 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...

  9. 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.

  10. Teaching Introductory Oceanography through Case Studies: Project based approach for general education students

    Science.gov (United States)

    Farnsworth, K. L.; House, M.; Hovan, S. A.

    2013-12-01

    A recent workshop sponsored by SERC-On the Cutting Edge brought together science educators from a range of schools across the country to discuss new approaches in teaching oceanography. In discussing student interest in our classes, we were struck by the fact that students are drawn to emotional or controversial topics such as whale hunting and tsunami hazard and that these kinds of topics are a great vehicle for introducing more complex concepts such as wave propagation, ocean upwelling and marine chemistry. Thus, we have developed an approach to introductory oceanography that presents students with real-world issues in the ocean sciences and requires them to explore the science behind them in order to improve overall ocean science literacy among non-majors and majors at 2 and 4 year colleges. We have designed a project-based curriculum built around topics that include, but are not limited to: tsunami hazard, whale migration, ocean fertilization, ocean territorial claims, rapid climate change, the pacific trash patch, overfishing, and ocean acidification. Each case study or project consists of three weeks of class time and is structured around three elements: 1) a media analysis; 2) the role of ocean science in addressing the issue; 3) human impact/response. Content resources range from textbook readings, popular or current print news, documentary film and television, and data available on the world wide web from a range of sources. We employ a variety of formative assessments for each case study in order to monitor student access and understanding of content and include a significant component of in-class student discussion and brainstorming guided by faculty input to develop the case study. Each study culminates in summative assessments ranging from exams to student posters to presentations, depending on the class size and environment. We envision this approach for a range of classroom environments including large group face-to-face instruction as well as hybrid

  11. Acoustic Force Density Acting on Inhomogeneous Fluids in Acoustic Fields

    DEFF Research Database (Denmark)

    Karlsen, Jonas Tobias; Augustsson, Per; Bruus, Henrik

    2016-01-01

    We present a theory for the acoustic force density acting on inhomogeneous fluids in acoustic fields on time scales that are slow compared to the acoustic oscillation period. The acoustic force density depends on gradients in the density and compressibility of the fluid. For microfluidic systems...

  12. Parametric Room Acoustic workflows with real-time acoustic simulation

    DEFF Research Database (Denmark)

    Parigi, Dario

    2017-01-01

    The paper investigates and assesses the opportunities that real-time acoustic simulation offer to engage in parametric acoustics workflow and to influence architectural designs from early design stages......The paper investigates and assesses the opportunities that real-time acoustic simulation offer to engage in parametric acoustics workflow and to influence architectural designs from early design stages...

  13. Rapid acoustic survey for biodiversity appraisal.

    Directory of Open Access Journals (Sweden)

    Jérôme Sueur

    Full Text Available Biodiversity assessment remains one of the most difficult challenges encountered by ecologists and conservation biologists. This task is becoming even more urgent with the current increase of habitat loss. Many methods-from rapid biodiversity assessments (RBA to all-taxa biodiversity inventories (ATBI-have been developed for decades to estimate local species richness. However, these methods are costly and invasive. Several animals-birds, mammals, amphibians, fishes and arthropods-produce sounds when moving, communicating or sensing their environment. Here we propose a new concept and method to describe biodiversity. We suggest to forego species or morphospecies identification used by ATBI and RBA respectively but rather to tackle the problem at another evolutionary unit, the community level. We also propose that a part of diversity can be estimated and compared through a rapid acoustic analysis of the sound produced by animal communities. We produced alpha and beta diversity indexes that we first tested with 540 simulated acoustic communities. The alpha index, which measures acoustic entropy, shows a logarithmic correlation with the number of species within the acoustic community. The beta index, which estimates both temporal and spectral dissimilarities, is linearly linked to the number of unshared species between acoustic communities. We then applied both indexes to two closely spaced Tanzanian dry lowland coastal forests. Indexes reveal for this small sample a lower acoustic diversity for the most disturbed forest and acoustic dissimilarities between the two forests suggest that degradation could have significantly decreased and modified community composition. Our results demonstrate for the first time that an indicator of biological diversity can be reliably obtained in a non-invasive way and with a limited sampling effort. This new approach may facilitate the appraisal of animal diversity at large spatial and temporal scales.

  14. Acoustic building infiltration measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Muehleisen, Ralph T.; Raman, Ganesh

    2018-04-10

    Systems and methods of detecting and identifying a leak from a container or building. Acoustic pressure and velocity are measured. Acoustic properties are acquired from the measured values. The acoustic properties are converted to infiltration/leakage information. Nearfield Acoustic Holography (NAH) may be one method to detect the leakages from a container by locating the noise sources.

  15. Acoustic well cleaner

    Science.gov (United States)

    Maki, Jr., Voldi E.; Sharma, Mukul M.

    1997-01-21

    A method and apparatus are disclosed for cleaning the wellbore and the near wellbore region. A sonde is provided which is adapted to be lowered into a borehole and which includes a plurality of acoustic transducers arranged around the sonde. Electrical power provided by a cable is converted to acoustic energy. The high intensity acoustic energy directed to the borehole wall and into the near wellbore region, redissolves or resuspends the material which is reducing the permeability of the formation and/or restricting flow in the wellbore.

  16. Impacts of short-time scale water column variability on broadband high-frequency acoustic wave propagation

    Science.gov (United States)

    Eickmeier, Justin

    Acoustical oceanography is one way to study the ocean, its internal layers, boundaries and all processes occurring within using underwater acoustics. Acoustical sensing techniques allows for the measurement of ocean processes from within that logistically or financially preclude traditional in-situ measurements. Acoustic signals propagate as pressure wavefronts from a source to a receiver through an ocean medium with variable physical parameters. The water column physical parameters that change acoustic wave propagation in the ocean include temperature, salinity, current, surface roughness, seafloor bathymetry, and vertical stratification over variable time scales. The impacts of short-time scale water column variability on acoustic wave propagation include coherent and incoherent surface reflections, wavefront arrival time delay, focusing or defocusing of the intensity of acoustic beams and refraction of acoustic rays. This study focuses on high-frequency broadband acoustic waves, and examines the influence of short-time scale water column variability on broadband high-frequency acoustics, wavefronts, from 7 to 28 kHz, in shallow water. Short-time scale variability is on the order of seconds to hours and the short-spatial scale variability is on the order of few centimeters. Experimental results were collected during an acoustic experiment along 100 m isobaths and data analysis was conducted using available acoustic wave propagation models. Three main topics are studied to show that acoustic waves are viable as a remote sensing tool to measure oceanographic parameters in shallow water. First, coherent surface reflections forming striation patterns, from multipath receptions, through rough surface interaction of broadband acoustic signals with the dynamic sea surface are analyzed. Matched filtered results of received acoustic waves are compared with a ray tracing numerical model using a sea surface boundary generated from measured water wave spectra at the time of

  17. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Connections Overview Find a Meeting Host a Meeting Volunteer Become a Volunteer Opportunities Support Overview Patient Events ... ANA About ANA Mission, Vision & Values Shop ANA Leadership & Staff Annual Reports Acoustic Neuroma Association 600 Peachtree ...

  18. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... with AN Healthcare Providers Acoustic Neuroma Association Donate Now Newly Diagnosed What is AN? Request a Patient ... Volunteer About ANA Get Info Shop ANA Donate Now DONATE Ways to Give Legacy Society Team ANA © ...

  19. Acoustics Noise Test Cell

    Data.gov (United States)

    Federal Laboratory Consortium — The Acoustic Noise Test Cell at the NASA/Caltech Jet Propulsion Laboratory (JPL) is located adjacent to the large vibration system; both are located in a class 10K...

  20. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Choosing a healthcare provider Request a patient kit Treatment Options Overview Observation Radiation Surgery What is acoustic neuroma Diagnosing Symptoms Side effects Question To Ask Treatment Options Back Overview Observation Radiation Surgery Choosing a ...

  1. Acoustic imaging system

    Science.gov (United States)

    Smith, Richard W.

    1979-01-01

    An acoustic imaging system for displaying an object viewed by a moving array of transducers as the array is pivoted about a fixed point within a given plane. A plurality of transducers are fixedly positioned and equally spaced within a laterally extending array and operatively directed to transmit and receive acoustic signals along substantially parallel transmission paths. The transducers are sequentially activated along the array to transmit and receive acoustic signals according to a preestablished sequence. Means are provided for generating output voltages for each reception of an acoustic signal, corresponding to the coordinate position of the object viewed as the array is pivoted. Receptions from each of the transducers are presented on the same display at coordinates corresponding to the actual position of the object viewed to form a plane view of the object scanned.

  2. Acoustic Igniter, Phase I

    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...

  3. Cryogenic Acoustic Suppression Testing

    Data.gov (United States)

    National Aeronautics and Space Administration — A proof-of-concept method utilizing a cryogenic fluid for acoustic suppression in rocket engine testing environments will be demonstrated. It is hypothesized that...

  4. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Mission, Vision & Values Shop ANA Leadership & Staff Annual Reports Acoustic Neuroma Association 600 Peachtree Parkway Suite 108 ... About ANA Mission, Vision & Values Leadership & Staff Annual Reports Shop ANA Home Learn Educational Video English English ...

  5. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... ANA About ANA Mission, Vision & Values Shop ANA Leadership & Staff Annual Reports Acoustic Neuroma Association 600 Peachtree ... info@ANAUSA.org About ANA Mission, Vision & Values Leadership & Staff Annual Reports Shop ANA Home Learn Educational ...

  6. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Click to learn more... LOGIN CALENDAR DONATE NEWS Home Learn Back Learn about acoustic neuroma AN Facts ... Vision & Values Leadership & Staff Annual Reports Shop ANA Home Learn Educational Video English English Arabic Catalan Chinese ( ...

  7. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Info Booklets Research Back ANA Survey/Registry AN Research ... About Back Learn more about ANA About ANA Mission, Vision & Values Shop ANA Leadership & Staff Annual Reports Acoustic ...

  8. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... a patient kit Treatment Options Overview Observation Radiation Surgery What is acoustic neuroma Diagnosing Symptoms Side effects ... To Ask Treatment Options Back Overview Observation Radiation Surgery Choosing a healthcare provider Request a patient kit ...

  9. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Back Learn more about ANA About ANA Mission, Vision & Values Shop ANA Leadership & Staff Annual Reports Acoustic ... 205-8211 info@ANAUSA.org About ANA Mission, Vision & Values Leadership & Staff Annual Reports Shop ANA Home ...

  10. Department of Cybernetic Acoustics

    Science.gov (United States)

    The development of the theory, instrumentation and applications of methods and systems for the measurement, analysis, processing and synthesis of acoustic signals within the audio frequency range, particularly of the speech signal and the vibro-acoustic signal emitted by technical and industrial equipments treated as noise and vibration sources was discussed. The research work, both theoretical and experimental, aims at applications in various branches of science, and medicine, such as: acoustical diagnostics and phoniatric rehabilitation of pathological and postoperative states of the speech organ; bilateral ""man-machine'' speech communication based on the analysis, recognition and synthesis of the speech signal; vibro-acoustical diagnostics and continuous monitoring of the state of machines, technical equipments and technological processes.

  11. 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...

  12. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Learn more about ANA About ANA Mission, Vision & Values Shop ANA Leadership & Staff Annual Reports Acoustic Neuroma ... 8211 info@ANAUSA.org About ANA Mission, Vision & Values Leadership & Staff Annual Reports Shop ANA Home Learn ...

  13. Acoustic MIMO signal processing

    CERN Document Server

    Huang, Yiteng; Chen, Jingdong

    2006-01-01

    A timely and important book addressing a variety of acoustic signal processing problems under multiple-input multiple-output (MIMO) scenarios. It uniquely investigates these problems within a unified framework offering a novel and penetrating analysis.

  14. 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...

  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. Acoustic ambient noise recorder

    Digital Repository Service at National Institute of Oceanography (India)

    Saran, A.K.; Navelkar, G.S.; Almeida, A.M.; More, S.R.; Chodankar, P.V.; Murty, C.S.

    with a robust outfit that can withstand high pressures and chemically corrosion resistant materials. Keeping these considerations in view, a CMOS micro-controller-based marine acoustic ambient noise recorder has been developed with a real time clock...

  17. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Request a patient kit Treatment Options Overview Observation Radiation Surgery What is acoustic neuroma Diagnosing Symptoms Side ... Question To Ask Treatment Options Back Overview Observation Radiation Surgery Choosing a healthcare provider Request a patient ...

  18. 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...

  19. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... About ANA Mission, Vision & Values Shop ANA Leadership & Staff Annual Reports Acoustic Neuroma Association 600 Peachtree Parkway ... ANAUSA.org About ANA Mission, Vision & Values Leadership & Staff Annual Reports Shop ANA Home Learn Educational Video ...

  20. Particle separation by phase modulated surface acoustic waves.

    Science.gov (United States)

    Simon, Gergely; Andrade, Marco A B; Reboud, Julien; Marques-Hueso, Jose; Desmulliez, Marc P Y; Cooper, Jonathan M; Riehle, Mathis O; Bernassau, Anne L

    2017-09-01

    High efficiency isolation of cells or particles from a heterogeneous mixture is a critical processing step in lab-on-a-chip devices. Acoustic techniques offer contactless and label-free manipulation, preserve viability of biological cells, and provide versatility as the applied electrical signal can be adapted to various scenarios. Conventional acoustic separation methods use time-of-flight and achieve separation up to distances of quarter wavelength with limited separation power due to slow gradients in the force. The method proposed here allows separation by half of the wavelength and can be extended by repeating the modulation pattern and can ensure maximum force acting on the particles. In this work, we propose an optimised phase modulation scheme for particle separation in a surface acoustic wave microfluidic device. An expression for the acoustic radiation force arising from the interaction between acoustic waves in the fluid was derived. We demonstrated, for the first time, that the expression of the acoustic radiation force differs in surface acoustic wave and bulk devices, due to the presence of a geometric scaling factor. Two phase modulation schemes are investigated theoretically and experimentally. Theoretical findings were experimentally validated for different mixtures of polystyrene particles confirming that the method offers high selectivity. A Monte-Carlo simulation enabled us to assess performance in real situations, including the effects of particle size variation and non-uniform acoustic field on sorting efficiency and purity, validating the ability to separate particles with high purity and high resolution.

  1. Archive of Geosample Data and Information from the University of Rhode Island (URI) Graduate School of Oceanography (GSO), Marine Geological Samples Laboratory (MGSL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Marine Geological Samples Laboratory (MGSL) of the Graduate School of Oceanography (GSO), University of Rhode Island is a partner in the Index to Marine and...

  2. Dissertations Initiative for the Advancement of Limnology and Oceanography DIALOG II. Abstracts of Ph.D. Dissertations Completed between September 1, 1994 - March 31, 1997

    National Research Council Canada - National Science Library

    Weiler, C

    1997-01-01

    The Dissertations Initiative for the Advancement of Limnology and Oceanography (DIALOG) was founded in 1994 to facilitate interdisciplinary, inter-institutional and international aquatic science research, understanding and collaborations...

  3. Meteorology, physical oceanography, transport of water, biogeochemistry, and other parameters collected at fixed locations in the open ocean from the OceanSITES network

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This collection comprises data covering meteorology, physical oceanography, transport of water, biogeochemistry, and parameters relevant to the carbon cycle, ocean...

  4. NASA's Student Airborne Research Program as a model for effective professional development experience in Oceanography

    Science.gov (United States)

    Palacios, S. L.; Kudela, R. M.; Clinton, N. E.; Atkins, N.; Austerberry, D.; Johnson, M.; McGonigle, J.; McIntosh, K.; O'Shea, J. J.; Shirshikova, Z.; Singer, N.; Snow, A.; Woods, R.; Schaller, E.; Shetter, R. E.

    2011-12-01

    With over half of the current earth and space science workforce expected to retire within the next 15 years, NASA has responded by cultivating young minds through programs such as the Student Airborne Research Program (SARP). SARP is a competitive internship that introduces upper-level undergraduates and early graduate students to Earth System Science research and NASA's Airborne Science Program. The program serves as a model for recruitment of very high caliber students into the scientific workforce. Its uniqueness derives from total vertical integration of hands-on experience at every stage of airborne science: aircraft instrumentation, flight planning, mission participation, field-work, analysis, and reporting of results in a competitive environment. At the conclusion of the program, students presented their work to NASA administrators, faculty, mentors, and the other participants with the incentive of being selected as best talk and earning a trip to the fall AGU meeting to present their work at the NASA booth. We hope lessons learned can inform the decisions of scientists at the highest levels seeking to broaden the appeal of research. In 2011, SARP was divided into three disciplinary themes: Oceanography, Land Use, and Atmospheric Chemistry. Each research group was mentored by an upper-level graduate student who was supervised by an expert faculty member. A coordinator managed the program and was supervised by a senior research scientist/administrator. The program is a model of knowledge transfer among the several levels of research: agency administration to the program coordinator, established scientific experts to the research mentors, and the research mentors to the pre-career student participants. The outcomes from this program include mission planning and institutional knowledge transfer from administrators and expert scientists to the coordinator and research mentors; personnel and project management from the coordinator and expert scientists to the

  5. Institute for Exploration Partnership with URI Graduate School of Oceanography Produces Opportunities for Deep Water Archaeological Investigation

    Science.gov (United States)

    Ballard, R. D.; Coleman, D.

    2002-12-01

    The Graduate School of Oceanography (GSO) at the University of Rhode Island (URI) under the auspices of its new Institute for Archaeological Oceanography (IAO) will soon be offering a Ph.D. program in Archaeological Oceanography. Although based within GSO, this new program is being carried out in cooperation with the Departments of History, Sociology and Anthropology, and Engineering, which will provide graduate course work in support of this effort. Students with strong backgrounds in the earth sciences as well as undergraduate course work in the humanities are being sought to apply for this program in 2003/2004 timeframe and beyond. A new family of remotely operated vehicle systems have been developed to support this effort as well as an on-going field program in the Central and Eastern Mediterranean and Black Seas and the Great Lakes. IAO's next major expedition will occur in the Black Sea and Eastern Mediterranean aboard the R/V KNORR in the summer of 2003 including the use of high-bandwidth ship to shore telecommunications to permit shore-based scientists and engineers the ability to participate in the sea-going program."

  6. Experiences of ocean literacy with different users of operational oceanography services and with high school students

    Science.gov (United States)

    Agostini, Paola; Coppini, Giovanni; Martinelli, Sara; Bonarelli, Roberto; Lecci, Rita; Pinardi, Nadia; Cretì, Sergio; Turrisi, Giuseppe; Ciliberti, Stefania Angela; Federico, Ivan; Mannarini, Gianandrea; Verri, Giorgia; Jansen, Eric; Lusito, Letizia; Macchia, Francesca; Montagna, Fabio; Buonocore, Mauro; Marra, Palmalisa; Tedesco, Luca; Cavallo, Arturo

    2017-04-01

    According to a common definition, ocean literacy is an understanding of the ocean's influence on people and people influence on the ocean. An ocean-literate person is able to make informed and responsible decisions regarding the ocean and its resources. To this aim, this paper presents operational oceanographic tools developed to meet the needs of different users, and activities performed in collaboration with high school students to support new developments of the same tools. Operational oceanography allows to deal with societal challenges such as maritime safety, coastal and marine environment management, climate change assessment and marine resources management. Oceanographic products from the European Copernicus Marine Monitoring Service - CMEMS are transformed and communicated to public and stakeholders through adding-value chains (downstreaming), which consider advanced visualization, usage of multi-channels technological platforms and specific models and algorithms. Sea Situational Awareness is strategically important for management and safety purposes of any marine domain and, in particular, the Mediterranean Sea and its coastal areas. Examples of applications for sea situational awareness and maritime safety are here presented, through user-friendly products available both by web and mobile channels (that already reach more than 100.000 users in the Mediterranean area). Further examples of ocean literacy are web bulletins used to communicate the technical contents and information related to oceanographic forecasts to a wide public. They are the result of a collaboration with high school students, with whom also other activities on improving products visualization and online communication have been performed.

  7. Experiential Learning: High School Student Response to Learning Oceanography at Sea

    Science.gov (United States)

    Fiedler, J. W.; Tamsitt, V. M.; Crosby, S. C.; Ludka, B. C.

    2016-12-01

    The GOTO-SEE (Graduate students Onboard Teaching Oceanography - Scripps Educational Experience) cruises were conducted with two days of ship time off of Point Loma, CA, on the R/V Robert Gordon Sproul in July 2016. The cruises, funded through UC Ship Funds program, provided a unique training opportunity for graduate students to design, coordinate and conduct ship-based field experiments as well as teaching and mentoring students. The cruises allowed for instruction at sea for high school students in the UCSD Academic Connections program in two small classes: a two-week long Global Environmental Leadership and Sustainability Program and a 3-week long class entitled Wind, Waves and Currents: Physics of the Ocean World. Students in both classes assisted with the collection of data, including two repeat cross-shore vertical CTD sections with nutrient sampling, and the deployment and recovery of a 10-day moored vertical thermistor array. Additional activities included plankton net tows, sediment sampling, depth soundings, and simple experiments regarding light absorption in the ocean. The students later plotted the data collected as a class assignment and presented a scientific poster to their peers. Here, we present the lessons learned from the cruises as well as student responses to the unique in-the-field experience, and how those responses differed by curriculum.

  8. Continental shelf processes affecting the oceanography of the South Atlantic Bight. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Pietrafesa, L.J.

    1978-03-01

    The objectives of the project were to determine the physical/dynamical processes controlling/affecting the distribution of phytoplankton nutrients on the continental shelf in the South Atlantic Bight. The initial objectives were to determine the short term, i.e., 2 to 10 day and longer term flux of nutrients onto the continental shelf. This is clearly related to the more general problem of combined physical and biogenic control of phytoplankton nutrients. During the period from June, 1975 to March, 1978 the study of the continental shelf processes affecting the oceanography of the South Atlantic Bight has been principally involved with a substantial, coordinated field effort. The success of the data acquisition phase of the program has now required an intensive data analysis phase which has been slowly increasing in effort. Emphasis is placed on the main phase of the field program, located in Onslow Bay, which has beel completed and the data are being analyzed. During the three-year period 20 cruises were made into the Carolina Capes area and samples were collected. A list is included of some 100 publications during the period.

  9. 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...

  10. West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume III. Biological oceanography. Final report

    Energy Technology Data Exchange (ETDEWEB)

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)

    1983-02-01

    The Department of Energy's Strategic Petroleum Reserve Program began discharging brine into the Gulf of Mexico from its West Hackberry site near Cameron, Louisiana in May 1981. The brine originates from underground salt domes being leached with water from the Intracoastal Waterway, making available vast underground storage caverns for crude oil. The effects of brine discharge on aquatic organisms are presented in this volume. The topics covered are: benthos; nekton; phytoplankton; zooplankton; and data management.

  11. Biologging, remotely-sensed oceanography and the continuous plankton recorder reveal the environmental determinants of a seabird wintering hotspot.

    Directory of Open Access Journals (Sweden)

    Jérôme Fort

    Full Text Available Marine environments are greatly affected by climate change, and understanding how this perturbation affects marine vertebrates is a major issue. In this context, it is essential to identify the environmental drivers of animal distribution. Here, we focused on the little auk (Alle alle, one of the world's most numerous seabirds and a major component in Arctic food webs. Using a multidisciplinary approach, we show how little auks adopt specific migratory strategies and balance environmental constraints to optimize their energy budgets. Miniature electronic loggers indicate that after breeding, birds from East Greenland migrate >2000 km to overwinter in a restricted area off Newfoundland. Synoptic data available from the Continuous Plankton Recorder (CPR indicate that this region harbours some of the highest densities of the copepod Calanus finmarchicus found in the North Atlantic during winter. Examination of large-scale climatic and oceanographic data suggests that little auks favour patches of high copepod abundance in areas where air temperature ranges from 0°C to 5°C. These results greatly advance our understanding of animal responses to extreme environmental constraints, and highlight that information on habitat preference is key to identifying critical areas for marine conservation.

  12. Biologging, remotely-sensed oceanography and the continuous plankton recorder reveal the environmental determinants of a seabird wintering hotspot.

    Science.gov (United States)

    Fort, Jérôme; Beaugrand, Grégory; Grémillet, David; Phillips, Richard A

    2012-01-01

    Marine environments are greatly affected by climate change, and understanding how this perturbation affects marine vertebrates is a major issue. In this context, it is essential to identify the environmental drivers of animal distribution. Here, we focused on the little auk (Alle alle), one of the world's most numerous seabirds and a major component in Arctic food webs. Using a multidisciplinary approach, we show how little auks adopt specific migratory strategies and balance environmental constraints to optimize their energy budgets. Miniature electronic loggers indicate that after breeding, birds from East Greenland migrate >2000 km to overwinter in a restricted area off Newfoundland. Synoptic data available from the Continuous Plankton Recorder (CPR) indicate that this region harbours some of the highest densities of the copepod Calanus finmarchicus found in the North Atlantic during winter. Examination of large-scale climatic and oceanographic data suggests that little auks favour patches of high copepod abundance in areas where air temperature ranges from 0°C to 5°C. These results greatly advance our understanding of animal responses to extreme environmental constraints, and highlight that information on habitat preference is key to identifying critical areas for marine conservation.

  13. 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...

  14. 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.

  15. Sea Turtle Acoustic Telemetry Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Acoustic transmitters attached to sea turtles captured in various fishing gear enable the animals to be passively tracked. Acoustic receivers set up in an array...

  16. 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...

  17. Acoustic analysis of explosions in high noise environment

    Science.gov (United States)

    Man, Hong; Desai, Sachi

    2008-04-01

    Explosion detection and recognition is a critical capability to provide situational awareness to the war-fighters in battlefield. Acoustic sensors are frequently deployed to detect such events and to trigger more expensive sensing/sensor modalities (i.e. radar, laser spectroscope, IR etc.). Acoustic analysis of explosions has been intensively studied to reliably discriminate mortars, artillery, round variations, and type of blast (i.e. chemical/biological or high-explosive). One of the major challenges is high level of noise, which may include non-coherent noise generated from the environmental background and coherent noise induced by possible mobile acoustic sensor platform. In this work, we introduce a new acoustic scene analysis method to effectively enhance explosion classification reliability and reduce the false alarm rate at low SNR and with high coherent noise. The proposed method is based on acoustic signature modeling using Hidden Markov Models (HMMs). Special frequency domain acoustic features characterizing explosions as well as coherent noise are extracted from each signal segment, which forms an observation vector for HMM training and test. Classification is based on a unique model similarity measure between the HMM estimated from the test observations and the trained HMMs. Experimental tests are based on the acoustic explosion dataset from US ARMY ARDEC, and experimental results have demonstrated the effectiveness of the proposed method.

  18. Acoustic integrated extinction

    OpenAIRE

    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. (2007 J. Acoust. Soc. Am. 122, 3206–3210. (doi:10.1121/1.2801546)) 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 der...

  19. Room Acoustical Fields

    CERN Document Server

    Mechel, Fridolin

    2013-01-01

    This book presents the theory of room acoustical fields and revises the Mirror Source Methods for practical computational use, emphasizing the wave character of acoustical fields.  The presented higher methods include the concepts of “Mirror Point Sources” and “Corner sources which allow for an excellent approximation of complex room geometries and even equipped rooms. In contrast to classical description, this book extends the theory of sound fields describing them by their complex sound pressure and the particle velocity. This approach enables accurate descriptions of interference and absorption phenomena.

  20. Acoustic emission intrusion detector

    International Nuclear Information System (INIS)

    Carver, D.W.

    1978-01-01

    In order to improve the security of handling special nuclear materials at the Oak Ridge Y-12 Plant, a sensitive acoustic emission detector has been developed that will detect forcible entry through block or tile walls, concrete floors, or concrete/steel vault walls. A small, low-powered processor was designed to convert the output from a sensitive, crystal-type acoustic transducer to an alarm relay signal for use with a supervised alarm loop. The unit may be used to detect forcible entry through concrete, steel, block, tile, and/or glass

  1. Carbon Nanotube Underwater Acoustic Thermophone

    Science.gov (United States)

    2016-09-23

    Attorney Docket No. 300009 1 of 8 A CARBON NANOTUBE UNDERWATER ACOUSTIC THERMOPHONE STATEMENT OF GOVERNMENT INTEREST [0001] The...the Invention [0003] The present invention is an acoustically transparent carbon nanotube thermophone. (2) Description of the Prior Art [0004...amplitude of the resulting sound waves. [0006] Recently, there has been development of underwater acoustic carbon nanotube (CNT) yarn sheets capable

  2. Seismic Oceanography in the Tyrrhenian Sea: Thermohaline Staircases, Eddies, and Internal Waves

    Science.gov (United States)

    Buffett, G. G.; Krahmann, G.; Klaeschen, D.; Schroeder, K.; Sallarès, V.; Papenberg, C.; Ranero, C. R.; Zitellini, N.

    2017-11-01

    We use seismic oceanography to document and analyze oceanic thermohaline fine structure across the Tyrrhenian Sea. Multichannel seismic (MCS) reflection data were acquired during the MEDiterranean OCcidental survey in April-May 2010. We deployed along-track expendable bathythermograph probes simultaneous with MCS acquisition. At nearby locations we gathered conductivity-temperature-depth data. An autonomous glider survey added in situ measurements of oceanic properties. The seismic reflectivity clearly delineates thermohaline fine structure in the upper 2,000 m of the water column, indicating the interfaces between Atlantic Water/Winter Intermediate Water, Levantine Intermediate Water, and Tyrrhenian Deep Water. We observe the Northern Tyrrhenian Anticyclone, a near-surface mesoscale eddy, plus laterally and vertically extensive thermohaline staircases. Using MCS, we are able to fully image the anticyclone to a depth of 800 m and to confirm the horizontal continuity of the thermohaline staircases of more than 200 km. The staircases show the clearest step-like gradients in the center of the basin while they become more diffuse toward the periphery and bottom, where impedance gradients become too small to be detected by MCS. We quantify the internal wave field and find it to be weak in the region of the eddy and in the center of the staircases, while it is stronger near the coastlines. Our results indicate this is because of the influence of the boundary currents, which disrupt the formation of staircases by preventing diffusive convection. In the interior of the basin, the staircases are clearer and the internal wave field weaker, suggesting that other mixing processes such as double diffusion prevail.

  3. Visualizing the Bay: Bringing a Research Experience into a High Enrollment Online Oceanography Course

    Science.gov (United States)

    Reed, D. L.; Anglin, J.

    2005-12-01

    General education courses at many universities are required to demonstrate specific student learning outcomes and methodologies of learning assessment that can be measure the success, or lack thereof, of meeting these outcomes. A primary learning outcome of the SJSU general education program is to have students apply a scientific approach to problems of the earth and environment. This requirement can be challenging in high enrollment classes offered at universities without the resources of graduate teaching assistantships. In order to meet this outcome through an active learning environment, we have redesigned a web-based oceanography course, primarily for non-science majors, that has students assume the role of shipboard scientists on a number of ocean-going virtual research experiences. One activity has students participate on a virtual research voyage based on a multi-beam sonar study of the central San Francisco Bay described in USGS Circular 1259 by Chin et al (2004). Students carry out the duties of virtual shipboard scientists, including pre- and post-cruise scientific meetings, sonar data acquisition, processing and visualization, and interpretation of the seafloor mapping data using a combination of scientific visualizations, animations, and audio and video segments. While on the voyage, students are required to: (1) determine the navigational hazards posed by three submerged rocks near the main shipping lane in the bay, (2) assess the long-term viability of a disposal site for mud dredged from the bay, and (3) generate a sediment characteristics map of the bay floor that can be used as a basis for future studies of contaminant transport. Upon completion of the voyage students are required to write an abstract describing their research for publication in the proceedings volume of a virtual scientific conference in the form of an essay question on the mid-term exam. Based on the work of over 200 students, this question has received the highest score of four

  4. how acoustic schwannomas?

    African Journals Online (AJOL)

    chemistry In the diagnosis of brain tumours and, furthermore, shows that acoustic schwannoma must be considered In the appropriate clinical setting, even in a group previously regarded as low-risk. S Atr Med J 1990; 78: 11-14. Studies from various parts of the world on the relative. freqIJency of primary intracranial tumours ...

  5. Nonlinear acoustic tomography

    International Nuclear Information System (INIS)

    Monk, P.

    1993-01-01

    The use of acoustic waves as probes to determine otherwise inaccessible properties of a medium is extremely widespread. Applications include sonar, medical imaging and non-destructive testing. Despite the importance of the applications, there is as yet no acceptable method for solving the full non-linear problem at resonance frequencies (frequencies at which the size of the features under investigations are approximately the wavelength of the incident acoustic field). The medical imaging problem, which consists in trying to determine the sound speed, density and absorption properties of a bounded inhomogeneous medium from scattered acoustic waves is the motivaiton for the investigation described in this paper. We shall present a solution technique for a standard model inverse acoustic scattering problem which consists of reconstructing the refractive index of an inhomogeneity from given far field data (far field data is essentially the measured scattered field at considerable distance from the inhomogeneity). This model inverse problem simplifies the inhomogeneity by neglecting density and absorption but includes two important features of the real problem: nonlinearity and illposedness. Furthermore the method we present can easily by extended to more general problems

  6. Acoustic emission from beryllium

    International Nuclear Information System (INIS)

    Heiple, C.R.; Adams, R.O.

    1976-01-01

    The acoustic emission from both powder and ingot source beryllium has been measured as a function of strain and prior heat treatment. Most measurements were made during tensile deformation, but a limited number of compression tests have also been performed. The acoustic emission observed was of the burst type, with little or no contribution from continuous type emission. The emission was characterized by the variation of burst rate and average energy per burst as a function of strain. The tensile behavior was qualitatively similar for all the materials tested. Burst rate maxima centered roughly at 0.1 percent and 1.0 percent plastic strain were observed. The magnitude but not the strain at the low strain burst rate peak was very sensitive to prior thermal treatment, while the higher strain burst rate peak was insensitive to prior heat treatment. An energy per burst maximum was observed at 0.2 percent plastic strain, the magnitude of which was moderately sensitive to heat treatment. The Kaiser effect is observed in the material studied. Emission during compression was similar to that observed in tension. The acoustic emission observed is attributed to dislocation motion, as proposed by James and Carpenter for LiF, NaCl, and Zn. Metallographic studies of the beryllium at various strains have ruled out microcracking and twin formation as major contributors to the acoustic emission

  7. Acoustic force spectroscopy

    NARCIS (Netherlands)

    Sitters, G.; Kamsma, D.; Thalhammer, G.; Ritsch-Marte, M.; Peterman, E.J.G.; Wuite, G.J.L.

    2015-01-01

    Force spectroscopy has become an indispensable tool to unravel the structural and mechanochemical properties of biomolecules. Here we extend the force spectroscopy toolbox with an acoustic manipulation device that can exert forces from subpiconewtons to hundreds of piconewtons on thousands of

  8. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... 770-205-8211 info@ANAUSA.org ANAwareness Week 2018 – read more Click to learn more... LOGIN CALENDAR ... DONATE Ways to Give Legacy Society Team ANA © 2018 Acoustic Neuroma Association • 600 Peachtree Parkway • Suite 108 • ...

  9. Diagnosing Acoustic Neuroma

    Science.gov (United States)

    ... triggered by a patient’s symptoms. The most common presenting feature of acoustic neuromas, occurring in 90% of patients, is unilateral hearing loss. When "pure tone audiometry" is used, the most common finding is high frequency hearing loss. The hearing loss ...

  10. Select Internet Resources on Acoustics

    Directory of Open Access Journals (Sweden)

    Angela R. Davis

    2016-12-01

    Full Text Available Merriam-Webster (2016 defines acoustics as, “a science that deals with the production, control, transmission, reception, and effects of sounds.” According to Rossing (2014, the study of acoustics began in ancient Greece with Pythagoras’ study of vibrating strings on musical instruments. Since those early beginnings, famous scientists including Rayleigh, Alexander Graham Bell, and Thomas Edison, have helped expand the field of acoustics to include architectural, physical, engineering, structural, underwater, physiological and psychological, musical acoustics, and speech. Acoustics is a highly interdisciplinary field and researchers may need resources from physics, medicine, and engineering to understand all aspects of their research.

  11. 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...

  12. In situ quantitative characterisation of the ocean water column using acoustic multibeam backscatter data

    Science.gov (United States)

    Lamarche, G.; Le Gonidec, Y.; Lucieer, V.; Lurton, X.; Greinert, J.; Dupré, S.; Nau, A.; Heffron, E.; Roche, M.; Ladroit, Y.; Urban, P.

    2017-12-01

    Detecting liquid, solid or gaseous features in the ocean is generating considerable interest in the geoscience community, because of their potentially high economic values (oil & gas, mining), their significance for environmental management (oil/gas leakage, biodiversity mapping, greenhouse gas monitoring) as well as their potential cultural and traditional values (food, freshwater). Enhancing people's capability to quantify and manage the natural capital present in the ocean water goes hand in hand with the development of marine acoustic technology, as marine echosounders provide the most reliable and technologically advanced means to develop quantitative studies of water column backscatter data. This is not developed to its full capability because (i) of the complexity of the physics involved in relation to the constantly changing marine environment, and (ii) the rapid technological evolution of high resolution multibeam echosounder (MBES) water-column imaging systems. The Water Column Imaging Working Group is working on a series of multibeam echosounder (MBES) water column datasets acquired in a variety of environments, using a range of frequencies, and imaging a number of water-column features such as gas seeps, oil leaks, suspended particulate matter, vegetation and freshwater springs. Access to data from different acoustic frequencies and ocean dynamics enables us to discuss and test multifrequency approaches which is the most promising means to develop a quantitative analysis of the physical properties of acoustic scatterers, providing rigorous cross calibration of the acoustic devices. In addition, high redundancy of multibeam data, such as is available for some datasets, will allow us to develop data processing techniques, leading to quantitative estimates of water column gas seeps. Each of the datasets has supporting ground-truthing data (underwater videos and photos, physical oceanography measurements) which provide information on the origin and

  13. Oceanographic data - Integrated acoustic and trawl survey of Pacific hake off the Pacific Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Integrated acoustic and trawl surveys are used to assess the distribution, biomass, and biology of Pacific hake along the Pacific coasts of the United States and...

  14. From Scientist to Educator: Oceanography in the Formal and Informal Classroom

    Science.gov (United States)

    Richardson, A. H.; Jasnow, M.; Srinivasan, M. S.; Rosmorduc, V.; Blanc, F.

    2002-12-01

    the role of the ocean in sustaining life on Earth. Activities on the back of the poster can be used as supplemental material in a middle school Earth science curriculum, and are suitable for individual instruction and for classroom or group exercises. This poster will be published in both English and French. Educational research indicates that an inquiry-based method of student engagement is an appropriate and effective teaching tool. These posters offer a fun and instructive environment to promote student interest in Earth Science in general and particularly in oceanography.

  15. Designing and Implementing Service Learning Projects in an Introductory Oceanography Course Using the ``8-Block Model''

    Science.gov (United States)

    Laine, E. P.; Field, C.

    2010-12-01

    The Campus Compact for New Hampshire (Gordon, 2003) introduced a practical model for designing service-learning exercises or components for new or existing courses. They divided the design and implementation process into eight concrete areas, the “8-Block Model”. Their goal was to demystify the design process of service learning courses by breaking it down into interconnected components. These components include: project design, community partner relations, the problem statement, building community in the classroom, building student capacity, project management, assessment of learning, and reflection and connections. The project design component of the “8-Block Model” asks that the service performed be consistent with the learning goals of the course. For science courses students carry out their work as a way of learning science and the process of science, not solely for the sake of service. Their work supports the goals of a community partner and the community partner poses research problems for the class in a letter on their letterhead. Linking student work to important problems in the community effectively engages students and encourages them to work at more sophisticated levels than usually seen in introductory science classes. Using team-building techniques, the classroom becomes a safe, secure learning environment that encourages sharing and experimentation. Targeted lectures, labs, and demonstrations build the capacity of students to do their research. Behind the scenes project management ensures student success. Learning is assessed using a variety of tools, including graded classroom presentations, poster sessions, and presentations and reports to community partners. Finally, students reflect upon their work and make connections between their research and its importance to the well being of the community. Over the past 10 years, we have used this approach to design and continually modify an introductory oceanography course for majors and non

  16. Acoustic Communication in Birds-Differences in Songs and Calls ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 6. Acoustic Communication in Birds - Differences in Songs and Calls, their Production and Biological ... Change in email domain name. Posted on 26 August 2016. The domain part of the email address of all email addresses used by the office of ...

  17. Acoustic control of mosquito larvae in artificial drinking water containers

    Science.gov (United States)

    Acoustic larvicide devices are part of an emerging technology that provides a non-chemical and non-biological means to reduce larval populations of key medically important mosquito species such as Aedes aegypti in containers or catchments of water. These devices could benefit integrated vector manag...

  18. 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.

  19. Perspectives on chemical oceanography in the 21st century: Participants of the COME ABOARD Meeting examine aspects of the field in the context of 40 years of DISCO

    Science.gov (United States)

    Fassbender, Andrea J.; Palevsky, Hilary I.; Martz, Todd R.; Ingalls, Anitra E.; Gledhill, Martha; Fawcett, Sarah E.; Brandes, Jay; Aluwihare, Lihini; Anderson, Robert M.; Bender, Sara; Boyle, Ed; Bronk, Debbie; Buesseler, Ken; Burdige, David J.; Casciotti, Karen; Close, Hilary; Conte, Maureen; Cutter, Greg; Estapa, Meg; Fennel, Katja; Ferron, Sara; Glazer, Brian; Goni, Miguel; Grand, Max; Guay, Chris; Hatta, Mariko; Hayes, Chris; Horner, Tristan; Ingall, Ellery; Johnson, Kenneth G.; Juranek, Laurie; Knapp, Angela; Lam, Phoebe; Luther, George; Matrai, Paty; Nicholson, David; Paytan, Adina; Pellenbarg, Robert; Popendorf, Kim; Reddy, Christopher M.; Ruttenberg, Kathleen; Sabine, Chris; Sansone, Frank; Shaltout, Nayrah; Sikes, Liz; Sundquist, Eric T.; Valentine, David; Wang, Zhao (Aleck); Wilson, Sam; Barrett, Pamela; Behrens, Melanie; Belcher, Anna; Biermann, Lauren; Boiteau, Rene; Clarke, Jennifer; Collins, Jamie; Coppola, Alysha; Ebling, Alina M.; Garcia-Tigreros, Fenix; Goldman, Johanna; Guallart, Elisa F.; Haskell, William; Hurley, Sarah; Janssen, David; Johnson, Winn; Lennhartz, Sinikka; Liu, Shuting; Rahman, Shaily; Ray, Daisy; Sarkar, Amit; Steiner, Zvika; Widner, Brittany; Yang, Bo

    2017-01-01

    The questions that chemical oceanographers prioritize over the coming decades, and the methods we use to address these questions, will define our field's contribution to 21st century science. In recognition of this, the U.S. National Science Foundation and National Oceanic and Atmospheric Administration galvanized a community effort (the Chemical Oceanography MEeting: A BOttom-up Approach to Research Directions, or COME ABOARD) to synthesize bottom-up perspectives on selected areas of research in Chemical Oceanography. Representing only a small subset of the community, COME ABOARD participants did not attempt to identify targeted research directions for the field. Instead, we focused on how best to foster diverse research in Chemical Oceanography, placing emphasis on the following themes: strengthening our core chemical skillset; expanding our tools through collaboration with chemists, engineers, and computer scientists; considering new roles for large programs; enhancing interface research through interdisciplinary collaboration; and expanding ocean literacy by engaging with the public. For each theme, COME ABOARD participants reflected on the present state of Chemical Oceanography, where the community hopes to go and why, and actionable pathways to get there. A unifying concept among the discussions was that dissimilar funding structures and metrics of success may be required to accommodate the various levels of readiness and stages of knowledge development found throughout our community. In addition to the science, participants of the concurrent Dissertations Symposium in Chemical Oceanography (DISCO) XXV, a meeting of recent and forthcoming Ph.D. graduates in Chemical Oceanography, provided perspectives on how our field could show leadership in addressing long-standing diversity and early-career challenges that are pervasive throughout science. Here we summarize the COME ABOARD Meeting discussions, providing a synthesis of reflections and perspectives on the

  20. An acoustic prion assay

    Directory of Open Access Journals (Sweden)

    Gordon Hayward

    2016-12-01

    Full Text Available An acoustic prion assay has been demonstrated for sheep brain samples. Only five false positives and no false negatives were observed in a test of 45 positive and 45 negative samples. The acoustic prion sensor was constructed using a thickness shear mode quartz resonator coated with a covalently bound recombinant prion protein. The characteristic indicator of a scrapie infected sheep brain sample was an observed shoulder in the frequency decrease in response to a sample.The response of the sensor aligns with a conformational shift in the surface protein and with the propagation mechanism of the disease. This alignment is evident in the response timing and shape, dependence on concentration, cross species behaviour and impact of blood plasma. This alignment is far from sufficient to prove the mechanism of the sensor but it does offer the possibility of a rapid and inexpensive additional tool to explore prion disease. Keywords: Prions, Thickness shear mode quartz sensor

  1. Suppression through acoustics

    Science.gov (United States)

    Beck, Kevin D.; Short, Kenneth R.; VanMeenen, Kirsten M.; Servatius, Richard J.

    2006-05-01

    This paper reviews research conducted by our laboratory exploring the possible use of acoustical stimuli as a tool for influencing behavior. Over the course of several programs, different types of acoustic stimuli have been evaluated for their effectiveness in disrupting targeting, balance, and high-order cognitive processes in both humans and animals. Escape responses are of particular use in this regard. An escape response serves not only as an objective measure of aversion, but as a potential substitute for ongoing behavior. We have also assessed whether the level of performance changes if the individual does not perform an escape response. In general these studies have both suggested certain types of sounds are more aversive or distracting than others. Although the laboratory development of additional stimuli needs to continue, we are taking the next step by testing some of the more effective stimuli in more applied experimental scenarios including those involving group dynamics.

  2. Acoustic classification of dwellings

    DEFF Research Database (Denmark)

    Berardi, Umberto; Rasmussen, Birgit

    2014-01-01

    Schemes for the classification of dwellings according to different building performances have been proposed in the last years worldwide. The general idea behind these schemes relates to the positive impact a higher label, and thus a better performance, should have. In particular, focusing on sound...... 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...

  3. A Martian acoustic anemometer.

    Science.gov (United States)

    Banfield, Don; Schindel, David W; Tarr, Steve; Dissly, Richard W

    2016-08-01

    An acoustic anemometer for use on Mars has been developed. To understand the processes that control the interaction between surface and atmosphere on Mars, not only the mean winds, but also the turbulent boundary layer, the fluxes of momentum, heat and molecular constituents between surface and atmosphere must be measured. Terrestrially this is done with acoustic anemometers, but the low density atmosphere on Mars makes it challenging to adapt such an instrument for use on Mars. This has been achieved using capacitive transducers and pulse compression, and was successfully demonstrated on a stratospheric balloon (simulating the Martian environment) and in a dedicated Mars Wind Tunnel facility. This instrument achieves a measurement accuracy of ∼5 cm/s with an update rate of >20 Hz under Martian conditions.

  4. Osmotic Acoustic Source

    Science.gov (United States)

    2017-09-25

    one side of the radiating surface that is on the order of one meter the length and width of the plane of the enclosure. The walls of the enclosure...DEPARTMENT OF THE NAVY OFFICE OF COUNSEL NAVAL UNDERSEA WARFARE CENTER DIVISION 1176 HOWELL STREET NEWPORT Rl 02841-1708...across a semi-permeable membrane. (2) Description of the Prior Art [0004] Low frequency acoustic sources such as in a range of one to ten Hertz are

  5. 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

  6. Deep Water Ocean Acoustics

    Science.gov (United States)

    2015-10-19

    to a maximum of 143.1°. The back- azimuth as a function of frequency does show coherent behavior, at least within the observed 0.3° small time...level vs. Phone Number (similar to depth) as function of time as the source moved from 10-20 km away. The structure of this interference pattern...dimensional long-range acoustic propagation for improved localisation methods” Dr. Heaney visited Emanuel Coelho at CMRE in La Spezia Italy and

  7. 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.

  8. Examples and applications in long-range ocean acoustics

    International Nuclear Information System (INIS)

    Vera, M D

    2007-01-01

    Acoustic energy propagates effectively to long ranges in the ocean interior because of the physical properties of the marine environment. Sound propagation in the ocean is relevant to a variety of studies in communication, climatology and marine biology. Examples drawn from ocean acoustics, therefore, are compelling to students with a variety of interests. The dependence of sound speed on depth results in a waveguide that permits the detection of acoustic energy at ranges, in some experiments, of thousands of kilometres. This effect serves as an illustration of Snell's law with a continuously variable index of refraction. Acoustic tomography also offers a means for imaging the ocean's thermal structure, because of the dependence of sound speed on temperature. The ability to perform acoustic thermometry for large transects of the ocean provides an effective means of studying climate change. This application in an area of substantial popular attention allows for an effective introduction to concepts in ray propagation. Aspects of computational ocean acoustics can be productive classroom examples in courses ranging from introductory physics to upper-division mathematical methods courses

  9. The Usage of Acoustic Emission in Apis mellifera Research

    Directory of Open Access Journals (Sweden)

    Koláček Stanislav

    2014-01-01

    Full Text Available This paper deals with acoustic emission (AE which was used to monitor group approximately ten pieces of honeybees in a glass jar. Acoustic emission is a part of the non-destructive methods and it is especially used for to monitor and detection defects of material on construction sites and industrial process. In the last time the acoustic emission was tested for very special objects such as to monitor of growth of plants or behaviour of insects. The mission this work was to apply a new experiment on the behaviour of colonies by means of acoustic emission, which it allows to capture waves and vibrations spreading in the material. Vibrations are one of the major parts of communication in the bee communities. Sensing colonies with the support of acoustic emission can be used for understanding of biological behaviour and reaction bees on different kinds of stimuli. During the experiment were used two sensors for to monitor the activities of selected bees diverging from the normal state were observed. The sensor No. 1 was mounted directly on the glass with using a rubber strip. The sensor No. 2 was mounted on the steel sheet by using a clamp. Whole glass jar was isolated with polystyrene against disturbing waves through the environment. The non-destructive method of acoustic emission was scanned activity of the selected bee sample in the immediate vicinity for approximately thirty hours.

  10. 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.

  11. Acoustically enhanced heat transport

    Science.gov (United States)

    Ang, Kar M.; Yeo, Leslie Y.; Friend, James R.; Hung, Yew Mun; Tan, Ming K.

    2016-01-01

    We investigate the enhancement of heat transfer in the nucleate boiling regime by inducing high frequency acoustic waves (f ˜ 106 Hz) on the heated surface. In the experiments, liquid droplets (deionized water) are dispensed directly onto a heated, vibrating substrate. At lower vibration amplitudes (ξs ˜ 10-9 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 (ξs ˜ 10-8 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 10-8 m with 106 Hz order frequencies is observed to produce an improvement of up to 50% reduction in the surface temperature over the case without acoustic excitation.

  12. Ocean Acoustic Propagation and Coherence Studies

    Science.gov (United States)

    2015-09-30

    Propagation variability is an inescapable complicating factor for both active and passive sonar systems, and for underwater acoustic communications...framework, to be exploited in the use of underwater sound in shallow water. Our knowledge of acoustic field patterns in shallow water, building block...Ocean Acoustics and Signals Laboratory . Five acoustic studies are planned: 1. Canyon and slope acoustics : Identify purely geometrically controlled

  13. Current and future prospects for the application of systematic theoretical methods to the study of problems in physical oceanography

    Energy Technology Data Exchange (ETDEWEB)

    Constantin, A., E-mail: adrian.constantin@kcl.ac.uk [Department of Mathematics, King' s College London, Strand, London WC2R 2LS (United Kingdom); Faculty of Mathematics, University of Vienna, Oskar-Morgenstern-Platz 1, 1090 Vienna (Austria); Johnson, R.S., E-mail: r.s.johnson@ncl.ac.uk [School of Mathematics & Statistics, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2016-09-07

    Highlights: • Systematic theoretical methods in studies of equatorial ocean dynamics. • Linear wave-current interactions in stratified flows. • Exact solutions – Kelvin waves, azimuthal non-uniform currents. • Three-dimensional nonlinear currents. • Hamiltonian formulation for the governing equations and for structure-preserving/enhancing approximations. - Abstract: This essay is a commentary on the pivotal role of systematic theoretical methods in physical oceanography. At some level, there will always be a conflict between theory and experiment/data collection: Which is pre-eminent? Which should come first? This issue appears to be particularly marked in physical oceanography, to the extreme detriment of the development of the subject. It is our contention that the classical theory of fluids, coupled with methods from the theory of differential equations, can play a significant role in carrying the subject, and our understanding, forward. We outline the philosophy behind a systematic theoretical approach, highlighting some aspects of equatorial ocean dynamics where these methods have already been successful, paving the way for much more in the future and leading, we expect, to the better understanding of this and many other types of ocean flow. We believe that the ideas described here promise to reveal a rich and beautiful dynamical structure.

  14. Current and future prospects for the application of systematic theoretical methods to the study of problems in physical oceanography

    International Nuclear Information System (INIS)

    Constantin, A.; Johnson, R.S.

    2016-01-01

    Highlights: • Systematic theoretical methods in studies of equatorial ocean dynamics. • Linear wave-current interactions in stratified flows. • Exact solutions – Kelvin waves, azimuthal non-uniform currents. • Three-dimensional nonlinear currents. • Hamiltonian formulation for the governing equations and for structure-preserving/enhancing approximations. - Abstract: This essay is a commentary on the pivotal role of systematic theoretical methods in physical oceanography. At some level, there will always be a conflict between theory and experiment/data collection: Which is pre-eminent? Which should come first? This issue appears to be particularly marked in physical oceanography, to the extreme detriment of the development of the subject. It is our contention that the classical theory of fluids, coupled with methods from the theory of differential equations, can play a significant role in carrying the subject, and our understanding, forward. We outline the philosophy behind a systematic theoretical approach, highlighting some aspects of equatorial ocean dynamics where these methods have already been successful, paving the way for much more in the future and leading, we expect, to the better understanding of this and many other types of ocean flow. We believe that the ideas described here promise to reveal a rich and beautiful dynamical structure.

  15. 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.

  16. Acoustic signals of baby black caimans.

    Science.gov (United States)

    Vergne, Amélie L; Aubin, Thierry; Taylor, Peter; Mathevon, Nicolas

    2011-12-01

    In spite of the importance of crocodilian vocalizations for the understanding of the evolution of sound communication in Archosauria and due to the small number of experimental investigations, information concerning the vocal world of crocodilians is limited. By studying black caimans Melanosuchus niger in their natural habitat, here we supply the experimental evidence that juvenile crocodilians can use a graded sound system in order to elicit adapted behavioral responses from their mother and siblings. By analyzing the acoustic structure of calls emitted in two different situations ('undisturbed context', during which spontaneous calls of juvenile caimans were recorded without perturbing the group, and a simulated 'predator attack', during which calls were recorded while shaking juveniles) and by testing their biological relevance through playback experiments, we reveal the existence of two functionally different types of juvenile calls that produce a different response from the mother and other siblings. Young black caimans can thus modulate the structure of their vocalizations along an acoustic continuum as a function of the emission context. Playback experiments show that both mother and juveniles discriminate between these 'distress' and 'contact' calls. Acoustic communication is thus an important component mediating relationships within family groups in caimans as it is in birds, their archosaurian relatives. Although probably limited, the vocal repertoire of young crocodilians is capable of transmitting the information necessary for allowing siblings and mother to modulate their behavior. Copyright © 2011 Elsevier GmbH. All rights reserved.

  17. Acoustic Imaging of Combustion Noise

    Science.gov (United States)

    Ramohalli, K. N.; Seshan, P. K.

    1984-01-01

    Elliposidal acoustic mirror used to measure sound emitted at discrete points in burning turbulent jets. Mirror deemphasizes sources close to target source and excludes sources far from target. At acoustic frequency of 20 kHz, mirror resolves sound from region 1.25 cm wide. Currently used by NASA for research on jet flames. Produces clearly identifiable and measurable variation of acoustic spectral intensities along length of flame. Utilized in variety of monitoring or control systems involving flames or other reacting flows.

  18. Tunable coupled surface acoustic cavities

    Science.gov (United States)

    de Lima, M. M.; Santos, P. V.; Kosevich, Yu. A.; Cantarero, A.

    2012-06-01

    We demonstrate the electric tuning of the acoustic field in acoustic microcavities (MCs) defined by a periodic arrangement of metal stripes within a surface acoustic delay line on LiNbO3 substrate. Interferometric measurements show the enhancement of the acoustic field distribution within a single MC, the presence of a "bonding" and "anti-bonding" modes for two strongly coupled MCs, as well as the positive dispersion of the "mini-bands" formed by five coupled MCs. The frequency and amplitude of the resonances can be controlled by the potential applied to the metal stripes.

  19. Sinusoidal Representation of Acoustic Signals

    Science.gov (United States)

    Honda, Masaaki

    Sinusoidal representation of acoustic signals has been an important tool in speech and music processing like signal analysis, synthesis and time scale or pitch modifications. It can be applicable to arbitrary signals, which is an important advantage over other signal representations like physical modeling of acoustic signals. In sinusoidal representation, acoustic signals are composed as sums of sinusoid (sine wave) with different amplitudes, frequencies and phases, which is based on the timedependent short-time Fourier transform (STFT). This article describes the principles of acoustic signal analysis/synthesis based on a sinusoid representation with focus on sine waves with rapidly varying frequency.

  20. Acoustic Communications Measurement Systems (ACOMMS)

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Design and develop adaptive signal processing techniques to improve underwater acoustic communications and networking. Phase coherent and incoherent signal...

  1. NDE Acoustic Microscopy Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The purpose is to develop advanced, more effective high-resolution micro-NDE materials characterization methods using scanning acoustic microscopy. The laboratory's...

  2. 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...

  3. CMEMS (Copernicus Marine Environment Monitoring Service) In Situ Thematic Assembly Centre: A service for operational Oceanography

    Science.gov (United States)

    Manzano Muñoz, Fernando; Pouliquen, Sylvie; Petit de la Villeon, Loic; Carval, Thierry; Loubrieu, Thomas; Wedhe, Henning; Sjur Ringheim, Lid; Hammarklint, Thomas; Tamm, Susanne; De Alfonso, Marta; Perivoliotis, Leonidas; Chalkiopoulos, Antonis; Marinova, Veselka; Tintore, Joaquin; Troupin, Charles

    2016-04-01

    Copernicus, previously known as GMES (Global Monitoring for Environment and Security), is the European Programme for the establishment of a European capacity for Earth Observation and Monitoring. Copernicus aims to provide a sustainable service for Ocean Monitoring and Forecasting validated and commissioned by users. From May 2015, the Copernicus Marine Environment Monitoring Service (CMEMS) is working on an operational mode through a contract with services engagement (result is regular data provision). Within CMEMS, the In Situ Thematic Assembly Centre (INSTAC) distributed service integrates in situ data from different sources for operational oceanography needs. CMEMS INSTAC is collecting and carrying out quality control in a homogeneous manner on data from providers outside Copernicus (national and international networks), to fit the needs of internal and external users. CMEMS INSTAC has been organized in 7 regional Dissemination Units (DUs) to rely on the EuroGOOS ROOSes. Each DU aggregates data and metadata provided by a series of Production Units (PUs) acting as an interface for providers. Homogeneity and standardization are key features to ensure coherent and efficient service. All DUs provide data in the OceanSITES NetCDF format 1.2 (based on NetCDF 3.6), which is CF compliant, relies on SeaDataNet vocabularies and is able to handle profile and time-series measurements. All the products, both near real-time (NRT) and multi-year (REP), are available online for every CMEMS registered user through an FTP service. On top of the FTP service, INSTAC products are available through Oceanotron, an open-source data server dedicated to marine observations dissemination. It provides services such as aggregation on spatio-temporal coordinates and observed parameters, and subsetting on observed parameters and metadata. The accuracy of the data is checked on various levels. Quality control procedures are applied for the validity of the data and correctness tests for the

  4. An Assessment of Student Learning in an Online Oceanography Course: Five Years After Implementation

    Science.gov (United States)

    Reed, D. L.

    2002-12-01

    The results of assessing student learning in an online oceanography class offered over the past five years are compiled to reveal several general trends. In order to understand the context of these trends, it is important to first note that SJSU has a two-tiered general education program consisting of a category of core courses for frosh and sophomores and an advanced category for juniors and seniors, most of whom are community college transfers. The course described in this study is in the latter category and therefore composed largely of seniors. Enrollments in the course have exploded from 6 students in a pilot section offered during the 1998 fall semester to over 170 students in the summer semester of 2002. The course is now offered in both semesters of the academic year with four sections offered during 2002 summer session as part of a system-wide conversion to year-round operation. No other course, be it classroom, hybrid or online, in the general education category has experienced the level of student demand as this online course. All sections of the online course reach enrollment limits in the first days of registration with an equal or greater number of students turned away each semester. More female, students of color, returning students and K-12 in-service teachers enroll in the online sections than in the equivalent classroom sections of the course. Students enroll in the online section for the convenience of self-paced learning since attending a classroom section is not a viable option. Enrollments in concurrent classroom sections have not been negatively impacted by the addition of online sections. Enrollment attrition is higher in the first few days of the online course, but similar to that experienced in the classroom sections, once the class is underway. However, student requests for incompletes tend to be somewhat higher in the online course, especially during the summer offerings. Learning outcomes are reviewed at the beginning of the course and

  5. 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...

  6. Double negative acoustic metastructure for attenuation of acoustic emissions

    Science.gov (United States)

    Kumar, Sanjay; Bhushan, Pulak; Prakash, Om; Bhattacharya, Shantanu

    2018-03-01

    Acoustic metamaterials hold great potential for attenuation of low frequency acoustic emissions. However, a fundamental challenge is achieving high transmission loss over a broad frequency range. In this work, we report a double negative acoustic metastructure for absorption of low frequency acoustic emissions in an aircraft. This is achieved by utilizing a periodic array of hexagonal cells interconnected with a neck and mounted with an elastic membrane on both ends. An average transmission loss of 56 dB under 500 Hz and an overall absorption of over 48% have been realized experimentally. The negative mass density is derived from the dipolar resonances created as a result of the in-phase movement of the membranes. Further, the negative bulk modulus is ascribed to the combined effect of out-of-phase acceleration of the membranes and the Helmholtz resonator. The proposed metastructure enables absorption of low frequency acoustic emissions with improved functionality that is highly desirable for varied applications.

  7. 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

  8. Oil sardine and Indian mackerel: Their fishery, problems and coastal oceanography

    Digital Repository Service at National Institute of Oceanography (India)

    Madhupratap, M.; Shetye, S.R.; Nair, K.N.V.; Nair, S.R.S.

    The sardine and mackerel fishery is commercially exploited successfully along the west coast of India. The fish itself times its appearance to exploit the productive southwest monsoon period. The chain of events-physical, chemical and biological...

  9. Surface Acoustic Wave Devices

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard

    application is modulation of optical waves in waveguides. This presentation elaborates on how a SAW is generated by interdigital transducers using a 2D model of a piezoelectric, inhomogeneous material implemented in the high-level programming language Comsol Multiphysics. The SAW is send through a model......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...

  10. Acoustic Properties of Cellulose

    Science.gov (United States)

    Trematerra, Amelia; Lombardi, Ilaria

    2017-08-01

    Cellulose is the oldest material for thermal insulation in construction field. Thomas Jefferson was the first architect that used the cellulose in his project of the Monticello house (1800). But only after 1945 that the cellulose from newsprint was used across America and northern Europe. In the 70s with the energy crisis it Austria, Czech Republic, Switzerland and Germany began the production of cellulose derived from paper newspapers. It used for both winter and summer thermal insulation, while respecting the environment. In this paper are reported acoustic measurements carried out with the tube of Kundt, with the cellulose melted and with glue with different thicknesses.

  11. Lecture Notes On Acoustics

    International Nuclear Information System (INIS)

    Kim, Yang Han

    2005-09-01

    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. Quantum positron acoustic waves

    Energy Technology Data Exchange (ETDEWEB)

    Metref, Hassina; Tribeche, Mouloud [Plasma Physics Group (PPG), Theoretical Physics Laboratory (TPL), Faculty of Physics, University of Bab-Ezzouar, USTHB, B.P. 32, El Alia, Algiers 16111 (Algeria)

    2014-12-15

    Nonlinear quantum positron-acoustic (QPA) waves are investigated for the first time, within the theoretical framework of the quantum hydrodynamic model. In the small but finite amplitude limit, both deformed Korteweg-de Vries and generalized Korteweg-de Vries equations governing, respectively, the dynamics of QPA solitary waves and double-layers are derived. Moreover, a full finite amplitude analysis is undertaken, and a numerical integration of the obtained highly nonlinear equations is carried out. The results complement our previously published results on this problem.

  13. 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.

  14. Research in Oceanography at MIT, 1 October 1974 - 31 December 1979.

    Science.gov (United States)

    1980-03-01

    has had responsibility for one major long term project on the chemistry, physics and biology of particulate matter in the oceans, and for two shorter...MANOP trap intercomparison. These profiles have yielded unique information on the chemistry, biology , morphology and flux of suspended material in the ...only near a large seamount . Wunsch has seen that there are many places where the energy level is substantially and significantly above the universal

  15. 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....

  16. 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....

  17. Acoustic Emission Technology and Application

    International Nuclear Information System (INIS)

    Joo, Y. S.; Lim, S. H.; Eom, H. S.; Kim, J. H.; Jung, H. K.

    2003-10-01

    Acoustic emission is the elastic wave that is generated by the rapid release of energy from the localized sources within a material. After the observation of acoustic emission phenomenon in 1950, the research and further investigation had been performed. Acoustic emission examination becomes a rapidly matured nondestructive testing method with demonstrated capabilities for characterizing material behavior and for detecting the defect. It is of interest as a possible passive monitoring technique for detecting, locating and characterizing the defects in component and structure. Acoustic emission technology has recently strengthened the on-line monitoring application for the detection of incipient failures and the assurance of structural integrity. The field of acoustic emission testing is still growing vigorously and presents many challenges. Especially, acoustic emission has been successfully applied in the leak detection of primary pressure boundary of nuclear power plants. In this state-of-art report, the principle, measurement and field applications of acoustic emission technique is reviewed and summarized. Acoustic emission technology will contribute to the assurance of nuclear safety as the on-line monitoring technique of structural integrity of NSSS components and structures

  18. Graphical methods and Cold War scientific practice: the Stommel Diagram's intriguing journey from the physical to the biological environmental sciences.

    Science.gov (United States)

    Vance, Tiffany C; Doel, Ronald E

    2010-01-01

    In the last quarter of the twentieth century, an innovative three-dimensional graphical technique was introduced into biological oceanography and ecology, where it spread rapidly. Used to improve scientists' understanding of the importance of scale within oceanic ecosystems, this influential diagram addressed biological scales from phytoplankton to fish, physical scales from diurnal tides to ocean currents, and temporal scales from hours to ice ages. Yet the Stommel Diagram (named for physical oceanographer Henry Stommel, who created it in 1963) had not been devised to aid ecological investigations. Rather, Stommel intended it to help plan large-scale research programs in physical oceanography, particularly as Cold War research funding enabled a dramatic expansion of physical oceanography in the 1960s. Marine ecologists utilized the Stommel Diagram to enhance research on biological production in ocean environments, a key concern by the 1970s amid growing alarm about overfishing and ocean pollution. Before the end of the twentieth century, the diagram had become a significant tool within the discipline of ecology. Tracing the path that Stommel's graphical techniques traveled from the physical to the biological environmental sciences reveals a great deal about practices in these distinct research communities and their relative professional and institutional standings in the Cold War era. Crucial to appreciating the course of that path is an understanding of the divergent intellectual and social contexts of the physical versus the biological environmental sciences.

  19. Wastewater treatment with acoustic separator

    Science.gov (United States)

    Kambayashi, Takuya; Saeki, Tomonori; Buchanan, Ian

    2017-07-01

    Acoustic separation is a filter-free wastewater treatment method based on the forces generated in ultrasonic standing waves. In this report, a batch-system separator based on acoustic separation was demonstrated using a small-scale prototype acoustic separator to remove suspended solids from oil sand process-affected water (OSPW). By applying an acoustic separator to the batch use OSPW treatment, the required settling time, which was the time that the chemical oxygen demand (COD) decreased to the environmental criterion (<200 mg/L), could be shortened from 10 to 1 min. Moreover, for a 10 min settling time, the acoustic separator could reduce the FeCl3 dose as coagulant in OSPW treatment from 500 to 160 mg/L.

  20. Acoustic localization of triggered lightning

    Science.gov (United States)

    Arechiga, Rene O.; Johnson, Jeffrey B.; Edens, Harald E.; Thomas, Ronald J.; Rison, William

    2011-05-01

    We use acoustic (3.3-500 Hz) arrays to locate local (thunder produced by triggered lightning in the Magdalena Mountains of central New Mexico. The locations of the thunder sources are determined by the array back azimuth and the elapsed time since discharge of the lightning flash. We compare the acoustic source locations with those obtained by the Lightning Mapping Array (LMA) from Langmuir Laboratory, which is capable of accurately locating the lightning channels. To estimate the location accuracy of the acoustic array we performed Monte Carlo simulations and measured the distance (nearest neighbors) between acoustic and LMA sources. For close sources (6 km) the error increases to 800 m for the nearest neighbors and 650 m for the Monte Carlo analysis. This work shows that thunder sources can be accurately located using acoustic signals.

  1. Coupled Acoustic-Mechanical Bandgaps

    DEFF Research Database (Denmark)

    Jensen, Jakob Søndergaard; Kook, Junghwan

    2016-01-01

    In this work, we study the existence of coupled bandgaps for corrugated plate structures and acoustic channels. The study is motivated by the observation that the performance of traditional bandgap structures, such as periodic plates, may be compromised due to the coupling to a surrounding acoustic...... medium and the presence of acoustic resonances. It is demonstrated that corrugation of the plate structure can introduce bending wave bandgaps and bandgaps in the acoustic domain in overlapping and audible frequency ranges. This effect is preserved also when taking the physical coupling between the two...... domains into account. Additionally, the coupling is shown to introduce extra gaps in the band structure due to modal interaction and the appearance of a cut-on frequency for the fundamental acoustic mode....

  2. Electron/electron acoustic instability

    International Nuclear Information System (INIS)

    Gary, S.P.

    1987-01-01

    The electron acoustic wave becomes a normal mode of an unmagnetized collisionless plasma in the presence of two electron components with similar densities, but strongly disparate temperatures. The characteristic frequency of this mode is the plasma frequency of the cooler electron component. If these two electron components have a relative drift speed several times the thermal speed of the cooler component, the electron/electron acoustic instability may arise. This paper describes the parametric dependences of the threshold drift speed and maximum growth rate of this instability, and compares these with the same properties of the electron/ion acoustic instability. Under the condition of zero current, the electron/ion acoustic instability typically has the lower threshold drift speed, so that observation of the electron/electron acoustic instability is a strong indication of the presence of an electrical current in the plasma

  3. Acoustic emission linear pulse holography

    Science.gov (United States)

    Collins, H.D.; Busse, L.J.; Lemon, D.K.

    1983-10-25

    This device relates to the concept of and means for performing Acoustic Emission Linear Pulse Holography, which combines the advantages of linear holographic imaging and Acoustic Emission into a single non-destructive inspection system. This unique system produces a chronological, linear holographic image of a flaw by utilizing the acoustic energy emitted during crack growth. The innovation is the concept of utilizing the crack-generated acoustic emission energy to generate a chronological series of images of a growing crack by applying linear, pulse holographic processing to the acoustic emission data. The process is implemented by placing on a structure an array of piezoelectric sensors (typically 16 or 32 of them) near the defect location. A reference sensor is placed between the defect and the array.

  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. Omnidirectional ventilated acoustic barrier

    Science.gov (United States)

    Zhang, Hai-long; Zhu, Yi-fan; Liang, Bin; Yang, Jing; Yang, Jun; Cheng, Jian-chun

    2017-11-01

    As an important problem in acoustics, sound insulation finds applications in a great variety of situations. In the existing schemes, however, there has always been a trade-off between the thinness of sound-insulating devices and their ventilating capabilities, limiting their potentials in the control of low-frequency sound in high ventilation environments. Here, we design and experimentally implement an omnidirectional acoustic barrier with a planar profile, subwavelength thickness ( 0.18 λ ), yet high ventilation. The proposed mechanism is based on the interference between the resonant scattering of discrete states and the background scattering of continuous states which induces a Fano-like asymmetric transmission profile. Benefitting from the binary-structured design of the coiled unit and hollow pipe, it maximally simplifies the design and fabrication while ensuring the ventilation for all the non-resonant units with open tubes. The simulated and measured results agree well, showing the effectiveness of our proposed mechanism to block low frequency sound coming from various directions while allowing 63% of the air flow to pass. We anticipate our design to open routes to design sound insulators and to enable applications in traditionally unattainable cases such as those calling for noise reduction and cooling simultaneously.

  6. Time-reversal acoustics

    Energy Technology Data Exchange (ETDEWEB)

    Fink, Mathias [Laboratoire Ondes et Acoustique, Ecole Superieure de Physique et de Chimie Industrielle de la Ville de Paris, Universite Denis Diderot, UMR CNRS 7587, 10 Rue Vauquelin, 75005 Paris (France)], E-mail: mathias.fink@espci.fr

    2008-10-15

    Time-reversal mirrors (TRMs) refocus an incident acoustic field to the position of the original source regardless of the complexity of the propagation medium. TRM's have now been implemented in a variety of physical scenarios from MHz ultrasonics with order centimeter aperture size to hundreds/thousands of Hz in ocean acoustics with order hundred meter aperture size. Common to this broad range of scales is a remarkable robustness exemplified by observations at all scales that the more complex the medium between the probe source and the TRM, the sharper the focus. The relation between the medium complexity and the size of the focal spot is studied in this paper. It is certainly the most exciting property of TRM compared to standard focusing devices. A TRM acts as an antenna that uses complex environments to appears wider than it is, resulting for a broadband pulse in a refocusing quality that does not depend of the TRM aperture. In this paper, we investigate the time-reversal approach in various media of increasing complexity and we discuss the link existing between time-reversal approach and local helioseismology where Green's functions can be extracted from diffusive noise.

  7. Acoustic Studies of the Large Scale Ocean Circulation

    Science.gov (United States)

    Menemenlis, Dimitris

    1999-01-01

    Detailed knowledge of ocean circulation and its transport properties is prerequisite to an understanding of the earth's climate and of important biological and chemical cycles. Results from two recent experiments, THETIS-2 in the Western Mediterranean and ATOC in the North Pacific, illustrate the use of ocean acoustic tomography for studies of the large scale circulation. The attraction of acoustic tomography is its ability to sample and average the large-scale oceanic thermal structure, synoptically, along several sections, and at regular intervals. In both studies, the acoustic data are compared to, and then combined with, general circulation models, meteorological analyses, satellite altimetry, and direct measurements from ships. Both studies provide complete regional descriptions of the time-evolving, three-dimensional, large scale circulation, albeit with large uncertainties. The studies raise serious issues about existing ocean observing capability and provide guidelines for future efforts.

  8. Predictive Acoustic Tracking with an Adaptive Neural Mechanism

    DEFF Research Database (Denmark)

    Shaikh, Danish; Manoonpong, Poramate

    2017-01-01

    model of the lizard peripheral auditory system to extract information regarding sound direction. This information is utilised by a neural machinery to learn the acoustic signal’s velocity through fast and unsupervised correlation-based learning adapted from differential Hebbian learning. This approach...... or particle filtering, generalised cross-correlation or steered response power techniques. The authors have previously developed a biologically-inspired mechanism that utilises two microphones to reactively track an acoustic signal in motion. The mechanism leverages the directional response of an mathematical...... has previously been validated in simulation and via robotic trials to track a continuous pure tone acoustic signal with a semi-circular motion trajectory and a constant but unknown angular velocity. The neural machinery has been shown to be able to learn different target angular velocities...

  9. Review of Progress in Acoustic Levitation

    Science.gov (United States)

    Andrade, Marco A. B.; Pérez, Nicolás; Adamowski, Julio C.

    2018-04-01

    Acoustic levitation uses acoustic radiation forces to counteract gravity and suspend objects in mid-air. Although acoustic levitation was first demonstrated almost a century ago, for a long time, it was limited to objects much smaller than the acoustic wavelength levitating at fixed positions in space. Recent advances in acoustic levitation now allow not only suspending but also rotating and translating objects in three dimensions. Acoustic levitation is also no longer restricted to small objects and can now be employed to levitate objects larger than the acoustic wavelength. This article reviews the progress of acoustic levitation, focusing on the working mechanism of different types of acoustic levitation devices developed to date. We start with a brief review of the theory. Then, we review the acoustic levitation methods to suspend objects at fixed positions, followed by the techniques that allow the manipulation of objects. Finally, we present a brief summary and offer some future perspectives for acoustic levitation.

  10. From Architectural Acoustics to Acoustical Architecture Using Computer Simulation

    DEFF Research Database (Denmark)

    Schmidt, Anne Marie Due; Kirkegaard, Poul Henning

    2005-01-01

    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...... to the design of Bagsvaerd Church by Jørn Utzon. The paper discusses the advantages and disadvantages of the programme in each phase compared to the works of architects not using acoustic simulation programmes. The conclusion of the paper points towards the need to apply the acoustic simulation programmes...

  11. How hummingbirds hum: Acoustic holography of hummingbirds during maneuvering flight

    Science.gov (United States)

    Hightower, Ben; Wijnings, Patrick; Ingersoll, Rivers; Chin, Diana; Scholte, Rick; Lentink, David

    2017-11-01

    Hummingbirds make a characteristic humming sound when they flap their wings. The physics and the biological significance of hummingbird aeroacoustics is still poorly understood. We used acoustic holography and high-speed cameras to determine the acoustic field of six hummingbirds while they either hovered stationary in front of a flower or maneuvered to track flower motion. We used a robotic flower that oscillated either laterally or longitudinally with a linear combination of 20 different frequencies between 0.2 and 20 Hz, a range that encompasses natural flower vibration frequencies in wind. We used high-speed marker tracking to dissect the transfer function between the moving flower, the head, and body of the bird. We also positioned four acoustic arrays equipped with 2176 microphones total above, below, and in front of the hummingbird. Acoustic data from the microphones were back-propagated to planes adjacent to the hummingbird to create the first real-time holograms of the pressure field a hummingbird generates in vivo. Integration of all this data offers insight into how hummingbirds modulate the acoustic field during hovering and maneuvering flight.

  12. MR of acoustic neuromas

    International Nuclear Information System (INIS)

    Suzuki, Masayuki; Takashima, Tsutomu; Kadoya, Masumi; Takahashi, Shiroh; Miyayama, Shiroh; Taira, Sakae; Kashihara, Kengo; Yamashima, Tetsumori; Itoh, Haruhide

    1989-01-01

    In this report, the relationship of acoustic neuromas to the adjacent cranial nerves is discussed. On T 1 -weighted images, the trigeminal nerve was detected in all 13 cases. Mild to marked compression of these nerves by the tumors was observed in eight cases. The extent of compression did not always correspond to the clinical symptoms. In four cases with a maximum tumor diameter of 2 cm or less, the 7th and 8th cranial nerves were identified. There was no facial palsy in these patients. Two patients with a tumor diameter of more than 2 cm also had no facial palsy. All patients, including those with small tumors, complained of hearing loss and/or tinnitus. While MR imaging has some limitations, it is an effective imaging modality for showing the relationship between tumors and nerves. (author)

  13. 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...... a minor effect on the power spectra, i.e. the maximum jumps from one spectral peak to another. Experiments with deconvolution demonstrate that the emission generating system at least at a fixed intensity can be regarded as being linear and characterized by its impulse response which is similar...... to the emission evoked by click stimuli. It is concluded that significant information is obtained by the click rather than by the tonal stimuli. The click-evoked emissions were also recorded from both ears in a consecutive series of 100 full-term and otherwise normal babies 2-4 days after birth. The emission...

  14. Acoustics of friction

    Science.gov (United States)

    Akay, Adnan

    2002-04-01

    This article presents an overview of the acoustics of friction by covering friction sounds, friction-induced vibrations and waves in solids, and descriptions of other frictional phenomena related to acoustics. Friction, resulting from the sliding contact of solids, often gives rise to diverse forms of waves and oscillations within solids which frequently lead to radiation of sound to the surrounding media. Among the many everyday examples of friction sounds, violin music and brake noise in automobiles represent the two extremes in terms of the sounds they produce and the mechanisms by which they are generated. Of the multiple examples of friction sounds in nature, insect sounds are prominent. Friction also provides a means by which energy dissipation takes place at the interface of solids. Friction damping that develops between surfaces, such as joints and connections, in some cases requires only microscopic motion to dissipate energy. Modeling of friction-induced vibrations and friction damping in mechanical systems requires an accurate description of friction for which only approximations exist. While many of the components that contribute to friction can be modeled, computational requirements become prohibitive for their contemporaneous calculation. Furthermore, quantification of friction at the atomic scale still remains elusive. At the atomic scale, friction becomes a mechanism that converts the kinetic energy associated with the relative motion of surfaces to thermal energy. However, the description of the conversion to thermal energy represented by a disordered state of oscillations of atoms in a solid is still not well understood. At the macroscopic level, friction interacts with the vibrations and waves that it causes. Such interaction sets up a feedback between the friction force and waves at the surfaces, thereby making friction and surface motion interdependent. Such interdependence forms the basis for friction-induced motion as in the case of

  15. Perspective: Acoustic metamaterials in transition

    KAUST Repository

    Wu, Ying

    2017-12-15

    Acoustic metamaterials derive their novel characteristics from the interaction between acoustic waves with designed structures. Since its inception seventeen years ago, the field has been driven by fundamental geometric and physical principles that guide the structure design rules as well as provide the basis for wave functionalities. Recent examples include resonance-based acoustic metasurfaces that offer flexible control of acoustic wave propagation such as focusing and re-direction; parity-time (PT)-symmetric acoustics that utilizes the general concept of pairing loss and gain to achieve perfect absorption at a single frequency; and topological phononics that can provide one-way edge state propagation. However, such novel functionalities are not without constraints. Metasurface elements rely on resonances to enhance their coupling to the incident wave; hence, its functionality is limited to a narrow frequency band. Topological phononics is the result of the special lattice symmetry that must be fixed at the fabrication stage. Overcoming such constraints naturally forms the basis for further developments. We identify two emergent directions: Integration of acoustic metamaterial elements for achieving broadband characteristics as well as acoustic wave manipulation tasks more complex than the single demonstrative functionality; and active acoustic metamaterials that can adapt to environment as well as to go beyond the constraints on the passive acoustic metamaterials. Examples of a successful recent integration of multi-resonators in achieving broadband sound absorption can be found in optimal sound-absorbing structures, which utilize causality constraint as a design tool in realizing the target-set absorption spectrum with a minimal sample thickness. Active acoustic metamaterials have also demonstrated the capability to tune bandgaps as well as to alter property of resonances in real time through stiffening of the spring constants, in addition to the PT symmetric

  16. Acoustic of monolithic dome structures

    Directory of Open Access Journals (Sweden)

    Mostafa Refat Ismail

    2018-03-01

    The interior of monolithic domes have perfect, concave shapes to ensure that sound travels through the dome and perfectly collected at different vocal points. These dome structures are utilized for domestic use because the scale allows the focal points to be positioned across daily life activities, thereby affecting the sonic comfort of the internal space. This study examines the various acoustic treatments and parametric configurations of monolithic dome sizes. A geometric relationship of acoustic treatment and dome radius is established to provide architects guidelines on the correct selection of absorption needed to maintain the acoustic comfort of these special spaces.

  17. North Pacific Acoustic Laboratory and Deep Water Acoustics

    Science.gov (United States)

    2016-10-27

    During FY16 the primary effort has been working on manuscripts as summarized below: 1) A test of deep water Rytov theory at 284 Hz and 107 km in... signal , while the ambient noise field is in direct competition with the received signal . Research conducted in the North Pacific Acoustic Laboratory...low-frequency, long-range, deep water, broadband acoustic propagation, the effects of ocean variability on signal coherence, and the fundamental

  18. Marine bioacoustics and technology: The new world of marine acoustic ecology

    Science.gov (United States)

    Hastings, Mardi C.; Au, Whitlow W. L.

    2012-11-01

    Marine animals use sound for communication, navigation, predator avoidance, and prey detection. Thus the rise in acoustic energy associated with increasing human activity in the ocean has potential to impact the lives of marine animals. Thirty years ago marine bioacoustics primarily focused on evaluating effects of human-generated sound on hearing and behavior by testing captive animals and visually observing wild animals. Since that time rapidly changing electronic and computing technologies have yielded three tools that revolutionized how bioacousticians study marine animals. These tools are (1) portable systems for measuring electrophysiological auditory evoked potentials, (2) miniaturized tags equipped with positioning sensors and acoustic recording devices for continuous short-term acoustical observation rather than intermittent visual observation, and (3) passive acoustic monitoring (PAM) systems for remote long-term acoustic observations at specific locations. The beauty of these breakthroughs is their direct applicability to wild animals in natural habitats rather than only to animals held in captivity. Hearing capabilities of many wild species including polar bears, beaked whales, and reef fishes have now been assessed by measuring their auditory evoked potentials. Miniaturized acoustic tags temporarily attached to an animal to record its movements and acoustic environment have revealed the acoustic foraging behavior of sperm and beaked whales. Now tags are being adapted to fishes in effort to understand their behavior in the presence of noise. Moving and static PAM systems automatically detect and characterize biological and physical features of an ocean area without adding any acoustic energy to the environment. PAM is becoming a powerful technique for understanding and managing marine habitats. This paper will review the influence of these transformative tools on the knowledge base of marine bioacoustics and elucidation of relationships between marine

  19. Dolphin Sounds-Inspired Covert Underwater Acoustic Communication and Micro-Modem

    OpenAIRE

    Gang Qiao; Yunjiang Zhao; Songzuo Liu; Muhammad Bilal

    2017-01-01

    A novel portable underwater acoustic modem is proposed in this paper for covert communication between divers or underwater unmanned vehicles (UUVs) and divers at a short distance. For the first time, real dolphin calls are used in the modem to realize biologically inspired Covert Underwater Acoustic Communication (CUAC). A variety of dolphin whistles and clicks stored in an SD card inside the modem helps to realize different biomimetic CUAC algorithms based on the specified covert scenario. I...

  20. Time-reversal acoustics and ultrasound-assisted convection-enhanced drug delivery to the brain

    OpenAIRE

    Olbricht, William; Sistla, Manjari; Ghandi, Gaurav; Lewis, George; Sarvazyan, Armen

    2013-01-01

    Time-reversal acoustics is an effective way of focusing ultrasound deep inside heterogeneous media such as biological tissues. Convection-enhanced delivery is a method of delivering drugs into the brain by infusing them directly into the brain interstitium. These two technologies are combined in a focusing system that uses a “smart needle” to simultaneously infuse fluid into the brain and provide the necessary feedback for focusing ultrasound using time-reversal acoustics. The effects of time...

  1. Isotropic transformation acoustics and applications

    Science.gov (United States)

    Su, Xiaoshi; Norris, Andrew N.

    2017-04-01

    A novel class of acoustic metamaterial is proposed for directional collimation of a cylindrical source into a plane wave beam. The effect is based on transformation acoustics which retains the exact form of the wave equation under conformal mapping from a circular region to a triangular area. The transformation is adjustable, allowing the acoustic energy to be equally radiated in three directions, or preferentially in a single direction. Importantly, the material properties in the physical domain are isotropic and therefore practically realizable. Two example devices are proposed using cylindrical elastic shells in water as the metamaterial elements and demonstrated using full wave simulations. This approach has potential applications beyond acoustic antenna design in beam-steering and wavefront manipulation.

  2. An Experimental Introduction to Acoustics

    Science.gov (United States)

    Black, Andy Nicholas; Magruder, Robert H.

    2017-11-01

    Learning and understanding physics requires more than studying physics texts. It requires doing physics. Doing research is a key opportunity for students to connect physical principles with their everyday experience. A powerful way to introduce students to research and technique is through subjects in which they might find interest. Presented is an experiment that serves to introduce an advanced undergraduate or high school student to conducting research in acoustics via an experiment involving a standard dreadnought acoustic guitar, recording industry-related equipment, and relevant industrial analysis software. This experimental process is applicable to a wide range of acoustical topics including both acoustic and electric instruments. Also, the student has a hands-on experience with relevant audio engineering technology to study physical principles.

  3. Thermal/acoustical insulation foam

    Science.gov (United States)

    Lin, R. Y.; Struzik, E. A.

    1976-01-01

    Lightweight low-density substance can be used as fire resistant insulation in aircraft. Material density can be controlled over range from 0.6-1.2 pounds per cubic foot and has good thermal and acoustic properties.

  4. NCPA Enhancement for Physical Acoustics

    National Research Council Canada - National Science Library

    Bass, Henry

    2001-01-01

    ...-rate scientists and students and carry out effective, ONR-supported research. Specific objectives of this grant are to support research and recruitment by enhancing the infrastructure in physical acoustics...

  5. Acoustic agglomeration methods and apparatus

    Science.gov (United States)

    Barmatz, M. B. (Inventor)

    1984-01-01

    Methods are described for using acoustic energy to agglomerate fine particles on the order of one micron diameter that are suspended in gas, to provide agglomerates large enough for efficient removal by other techniques. The gas with suspended particles, is passed through the length of a chamber while acoustic energy at a resonant chamber mode is applied to set up one or more acoustic standing wave patterns that vibrate the suspended particles to bring them together so they agglomerate. Several widely different frequencies can be applied to efficiently vibrate particles of widely differing sizes. The standing wave pattern can be applied along directions transversed to the flow of the gas. The particles can be made to move in circles by applying acoustic energy in perpendicular directions with the energy in both directions being of the same wavelength but 90 deg out of phase.

  6. 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...

  7. PVT Degradation Studies: Acoustic Diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Dib, Gerges [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tucker, Brian J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kouzes, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smith, Philip J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-04-01

    Under certain environmental conditions, polyvinyl toluene (PVT) plastic scintillator has been observed to undergo internal fogging. This document reports on a study of acoustic techniques to determine whether they can provide a diagnostic for the fogging of PVT. Different ultrasound techniques were employed for detecting the level of internal fogging in PVT, including wave velocity measurements, attenuation, nonlinear acoustics, and acoustic microscopy. The results indicate that there are linear relations between the wave velocity and wave attenuation with the level of internal fogging. The effects of fogging on ultrasound wave attenuation is further verified by acoustic microscopy imaging, where regions with fog in the specimen demonstration higher levels of attenuation compared to clear regions. Results from the nonlinear ultrasound measurements were inconclusive due to high sensitivities to transducer coupling and fixture variabilities.

  8. Acoustical Properties of Contemporary Mosques

    Directory of Open Access Journals (Sweden)

    Karaman Özgül Yılmaz

    2017-04-01

    Full Text Available Religious buildings are important for many communities because of their representation of different beliefs. In such structures, the sense of individuality or unity & togetherness are created according to variable worship activities; these different uses have also different acoustical requirements. In order to create the desired feeling in the space at the required time, rooms should be evaluated in terms of acoustical conditions.

  9. Temperature, salinity, chlorophyll pigments, nutrients and other parameters as part of the ECOHAB-GOM: The Ecology and Oceanography of Toxic Alexandrium Blooms in the Gulf of Maine project (NODC Accession 0064309)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The subproject described here is one of several components of ECOHAB-GOM: The Ecology and Oceanography of Toxic Alexandrium Blooms in the Gulf of Maine, a multi-PI,...

  10. Physical trajectory profile data from glider sp053 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2016-07-20 to 2016-10-20 (NCEI Accession 0156796)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  11. Physical trajectory profile data from glider sp041 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-08 to 2016-12-14 (NCEI Accession 0157607)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  12. Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-03-10 to 2016-06-28 (NCEI Accession 0155280)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  13. Physical trajectory profile data from glider sp042 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2016-11-04 to 2017-02-23 (NCEI Accession 0161310)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  14. Physical trajectory profile data from glider sp052 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-07-28 to 2016-02-18 (NCEI Accession 0145670)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  15. Physical trajectory profile data from glider sp050 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2015-02-06 to 2015-05-14 (NCEI Accession 0137988)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  16. Physical trajectory profile data from glider sp064 deployed by University of California - San Diego; Scripps Institution of Oceanography in the |Coastal Waters of California from 2016-12-14 to 2017-03-29 (NCEI Accession 0162258)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  17. Physical trajectory profile data from glider sp001 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-01-12 to 2015-04-08 (NCEI Accession 0137973)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  18. Physical trajectory profile data from glider sp024 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2017-01-30 to 2017-05-08 (NCEI Accession 0162888)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...

  19. Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-12-14 to 2017-03-28 (NCEI Accession 0162257)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  20. Physical trajectory profile data from glider sp001 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2016-08-15 to 2016-11-16 (NCEI Accession 0157002)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  1. Physical trajectory profile data from glider sp026 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2017-04-20 to 2017-07-31 (NCEI Accession 0164709)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...

  2. Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-08-17 to 2016-09-16 (NCEI Accession 0156601)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  3. Physical trajectory profile data from glider sp054 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-03-17 to 2016-10-11 (NCEI Accession 0156772)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  4. Physical trajectory profile data from glider sp053 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-08-29 to 2015-12-13 (NCEI Accession 0145713)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  5. Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-02-18 to 2016-06-02 (NCEI Accession 0153551)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  6. Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-11-30 to 2017-03-14 (NCEI Accession 0162197)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  7. Physical trajectory profile data from glider sp056 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-03-29 to 2017-07-01 (NCEI Accession 0164292)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...

  8. Physical trajectory profile data from glider sp055 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-03-14 to 2017-06-28 (NCEI Accession 0163867)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...

  9. Physical trajectory profile data from glider sp052 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-06 to 2017-03-14 (NCEI Accession 0162198)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  10. Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-06-28 to 2016-08-23 (NCEI Accession 0156400)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  11. Physical trajectory profile data from glider sp039 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-02-18 to 2016-09-06 (NCEI Accession 0156570)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  12. Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-04-05 to 2017-07-11 (NCEI Accession 0164208)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...

  13. Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-03-28 to 2017-07-11 (NCEI Accession 0164207)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...

  14. Physical trajectory profile data from glider sp050 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2016-03-30 to 2016-07-20 (NCEI Accession 0155979)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  15. Physical trajectory profile data from glider sp049 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-05-18 to 2017-08-24 (NCEI Accession 0165396)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...

  16. Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-06 to 2016-11-30 (NCEI Accession 0157115)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  17. Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-13 to 2016-12-14 (NCEI Accession 0157580)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  18. Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-11-25 to 2014-11-27 (NCEI Accession 0137979)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  19. Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-09 to 2015-04-27 (NCEI Accession 0137984)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  20. Physical trajectory profile data from glider sp043 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2016-05-20 to 2016-08-24 (NCEI Accession 0156529)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  1. Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-11-24 to 2016-03-10 (NCEI Accession 0145666)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  2. Physical trajectory profile data from glider sp043 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2014-09-27 to 2015-01-04 (NCEI Accession 0137986)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  3. Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-11-05 to 2016-02-18 (NCEI Accession 0145664)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  4. Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-12-10 to 2015-03-31 (NCEI Accession 0137982)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  5. Physical trajectory profile data from glider sp064 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-05-17 to 2016-08-23 (NCEI Accession 0156410)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  6. Physical trajectory profile data from glider sp042 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-03-18 to 2015-05-27 (NCEI Accession 0137985)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  7. Physical trajectory profile data from glider sp027 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-06-16 to 2015-09-23 (NCEI Accession 0145712)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  8. Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-05-01 to 2014-08-13 (NCEI Accession 0137974)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  9. Physical trajectory profile data from glider sp063 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-02-03 to 2016-05-17 (NCEI Accession 0153552)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  10. Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-09-23 to 2015-01-09 (NCEI Accession 0137975)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  11. Physical trajectory profile data from glider sp063 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-08-23 to 2016-08-28 (NCEI Accession 0156530)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  12. Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-04-27 to 2015-08-13 (NCEI Accession 0137976)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  13. Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-08-13 to 2014-11-25 (NCEI Accession 0137983)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  14. Physical trajectory profile data from glider sp040 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-04-09 to 2015-07-14 (NCEI Accession 0138034)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  15. Physical trajectory profile data from glider sp052 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-08-14 to 2015-01-09 (NCEI Accession 0137990)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  16. Physical trajectory profile data from glider sp051 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-11-12 to 2015-01-08 (NCEI Accession 0137989)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  17. Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-06-05 to 2014-09-05 (NCEI Accession 0137981)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  18. Physical trajectory profile data from glider sp020 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2015-12-16 to 2016-03-30 (NCEI Accession 0153550)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  19. Physical trajectory profile data from glider sp048 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-27 to 2015-08-27 (NCEI Accession 0145669)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  20. Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-08 to 2015-04-09 (NCEI Accession 0137980)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  1. Physical trajectory profile data from glider sp048 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-01-16 to 2014-07-29 (NCEI Accession 0138035)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  2. Physical trajectory profile data from glider sp047 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-06-23 to 2015-01-22 (NCEI Accession 0137987)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  3. Physical trajectory profile data from glider sp047 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-08-27 to 2016-03-17 (NCEI Accession 0145668)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  4. Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-06-11 to 2014-09-15 (NCEI Accession 0137978)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  5. Physical trajectory profile data from glider sp035 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-03-31 to 2015-07-16 (NCEI Accession 0138032)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  6. Physical trajectory profile data from glider sp020 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2014-08-03 to 2014-12-12 (NCEI Accession 0137977)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  7. Physical trajectory profile data from glider sp031 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2014-04-12 to 2014-08-02 (NCEI Accession 0138031)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  8. Physical trajectory profile data from glider sp018 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2014-06-10 to 2014-09-21 (NCEI Accession 0138030)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  9. Physical trajectory profile data from glider sp063 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-09-15 to 2014-11-04 (NCEI Accession 0137991)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  10. Physical trajectory profile data from glider sp018 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2016-02-18 to 2016-05-28 (NCEI Accession 0153549)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  11. Physical trajectory profile data from glider sp064 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-10-30 to 2016-02-03 (NCEI Accession 0145715)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  12. Physical trajectory profile data from glider sp049 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-04-05 to 2016-06-02 (NCEI Accession 0153788)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  13. Physical trajectory profile data from glider sp031 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2015-09-10 to 2015-12-16 (NCEI Accession 0145667)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  14. Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-06-02 to 2016-09-06 (NCEI Accession 0156569)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  15. Physical trajectory profile data from glider sp039 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-22 to 2015-07-16 (NCEI Accession 0138033)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  16. Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-08-13 to 2015-11-18 (NCEI Accession 0145665)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  17. Physical trajectory profile data from glider sp006 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-12-14 to 2016-03-30 (NCEI Accession 0153787)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...

  18. Opto-acoustic transducer for medical applications

    Science.gov (United States)

    Benett, W.; Celliers, P.; Da Silva, L.; Glinsky, M.; London, R.; Maitland, D.; Matthews, D.; Krulevich, P.; Lee, A.

    1999-08-31

    This invention is an optically activated transducer for generating acoustic vibrations in a biological medium. The transducer is located at the end of a fiber optic which may be located within a catheter. Energy for operating the transducer is provided optically by laser light transmitted through the fiber optic to the transducer. Pulsed laser light is absorbed in the working fluid of the transducer to generate a thermal pressure and consequent adiabatic expansion of the transducer head such that it does work against the ambient medium. The transducer returns to its original state by a process of thermal cooling. The motion of the transducer within the ambient medium couples acoustic energy into the medium. By pulsing the laser at a high repetition rate (which may vary from CW to 100 kHz) an ultrasonic radiation field can be established locally in the medium. This method of producing ultrasonic vibrations can be used in vivo for the treatment of stroke-related conditions in humans, particularly for dissolving thrombus. The catheter may also incorporate anti-thrombolytic drug treatments as an adjunct therapy and it may be operated in conjunction with ultrasonic detection equipment for imaging and feedback control. 7 figs.

  19. Acoustic effects of the ATOC signal (75 Hz, 195 dB) on dolphins and whales

    Energy Technology Data Exchange (ETDEWEB)

    Au, W.W.; Nachtigall, P.E.; Pawloski, J.L. [Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii, P.O. Box 1106, Kailua, Hawaii 96734 (United States)

    1997-05-01

    The Acoustic Thermometry of Ocean Climate (ATOC) program of Scripps Institution of Oceanography and the Applied Physics Laboratory, University of Washington, will broadcast a low-frequency 75-Hz phase modulated acoustic signal over ocean basins in order to study ocean temperatures on a global scale and examine the effects of global warming. One of the major concerns is the possible effect of the ATOC signal on marine life, especially on dolphins and whales. In order to address this issue, the hearing sensitivity of a false killer whale ({ital Pseudorca crassidens}) and a Risso{close_quote}s dolphin ({ital Grampus griseus}) to the ATOC sound was measured behaviorally. A staircase procedure with the signal levels being changed in 1-dB steps was used to measure the animals{close_quote} threshold to the actual ATOC coded signal. The results indicate that small odontocetes such as the {ital Pseudorca} and {ital Grampus} swimming directly above the ATOC source will not hear the signal unless they dive to a depth of approximately 400 m. A sound propagation analysis suggests that the sound-pressure level at ranges greater than 0.5 km will be less than 130 dB for depths down to about 500 m. Several species of baleen whales produce sounds much greater than 170{endash}180 dB. With the ATOC source on the axis of the deep sound channel (greater than 800 m), the ATOC signal will probably have minimal physical and physiological effects on cetaceans. {copyright} {ital 1997 Acoustical Society of America.}

  20. 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.

  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. PORTABLE ACOUSTIC MONITORING PACKAGE (PAMP)

    Energy Technology Data Exchange (ETDEWEB)

    John l. Loth; Gary J. Morris; George M. Palmer; Richard Guiler; Deepak Mehra

    2003-07-01

    The 1st generation acoustic monitoring package was designed to detect and analyze weak acoustic signals inside natural gas transmission lines. Besides a microphone it housed a three-inch diameter aerodynamic acoustic signal amplifier to maximize sensitivity to leak induced {Delta}p type signals. The theory and test results of this aerodynamic signal amplifier was described in the master's degree thesis of our Research Assistant Deepak Mehra who is about to graduate. To house such a large three-inch diameter sensor required the use of a steel 300-psi rated 4 inch weld neck flange, which itself weighed already 29 pounds. The completed 1st generation Acoustic Monitoring Package weighed almost 100 pounds. This was too cumbersome to mount in the field, on an access port at a pipeline shut-off valve. Therefore a 2nd generation and truly Portable Acoustic Monitor was built. It incorporated a fully self-contained {Delta}p type signal sensor, rated for line pressures up to 1000 psi with a base weight of only 6 pounds. This is the Rosemont Inc. Model 3051CD-Range 0, software driven sensor, which is believed to have industries best total performance. Its most sensitive unit was purchased with a {Delta}p range from 0 to 3 inch water. This resulted in the herein described 2nd generation: Portable Acoustic Monitoring Package (PAMP) for pipelines up to 1000 psi. Its 32-pound total weight includes an 18-volt battery. Together with a 3 pound laptop with its 4-channel data acquisition card, completes the equipment needed for field acoustic monitoring of natural gas transmission pipelines.

  3. Radiological evaluation of acoustic neurinoma

    International Nuclear Information System (INIS)

    Lee, Jong Tae; Park, Chang Yun; Choi, Byung So

    1974-01-01

    All 25 patients surgically proven acoustic neurinoma was analysed clinically, radiographically at Severance Hospital of Yonsei Univ. The patients not proved surgically in spite of clinical diagnosis of acoustic neurinoma was excluded from this study. The results are summarized as follows; The clinical findings are; 1. The incidence of tumor in female was twice more frequent than in male and the range of age was 20-50 years peak of age at onset of symptom. 2. The clinical symptoms were variable from unilateral hearing impairment or less (100%), headache (84%) to tinnitus (60%) in order of frequency. 3. The tumor growth in the left cerebellopontine angle was twice more than in the right side with the radio of 16:8. However, in one case bilateral simultaneous growth of acoustic neurinoma was noted. The radiological findings are: The best radiographic method to study the shape and size of internal acoustic canal to demonstrate erosion or destruction of petrous pyramida was considered to be straight frontal view and tomography of the skull in our series. 1. The shape of internal acoustic canal in tumors were straight (in 2 cases), bulbous (in 12 cases), and flared (in 11 cases). Particularly there was erosion or destruction of petrous bone in all of the flared cases of canal. 2. The acoustic meatal erosion was mainly suprameatal in 14 cases of 17 which was noted definite erosion radiographically. 3. The difference of height (vertical diameter) of both side of acoustic canal were follows; 6 cases among 25 was in the range of 0-2 mm measurement, remainder was more than 2 mm. Hence the variation in greater than 1 mm in between both sides of canal in same patient should be regard as abnormal as of acoustic neurinoma. 4. The carotid angiogram shows hydrocephalic pattern in 12 cases among 17. 5. In the vertebral angiogram of 8 cases, anterolateral displacement of basilar artery (in 6 caes), the upward displacement of superior cerebellar artery (in 4 cases) was common findings

  4. 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

  5. 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

  6. 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.

  7. Acoustic emission from polycrystalline graphites

    International Nuclear Information System (INIS)

    Ioka, I.; Yoda, S.; Oku, T.; Miyamoto, Y.

    1987-01-01

    Acoustic emission was monitored from polycrystalline graphites with different microstructure (pore size and pore volume) subjected to compressive loading. The graphites used in this study comprised five brands, that is, PGX, ISEM-1, IG-11, IG-15, and ISO-88. A root mean square (RMS) voltage and event counts of acoustic emission for graphites were measured during compressive loading. The acoustic emission was measured using a computed-based data acquisition and analysis system. The graphites were first deformed up to 80 % of the average fracture stress, then unloaded and reloaded again until the fracture occured. During the first loading, the change in RMS voltage for acoustic emission was detected from the initial stage. During the unloading, the RMS voltage became zero level as soon as the applied stress was released and then gradually rose to a peak and declined. The behavior indicated that the reversed plastic deformation occured in graphites. During the second loading, the RMS voltage gently increased until the applied stress exceeded the maximum stress of the first loading; there is no Kaiser effect in the graphites. A bicrystal model could give a reasonable explanation of this results. The empirical equation between the ratio of σ AE to σ f and σ f was obtained. It is considered that the detection of microfracture by the acoustic emission technique is effective in macrofracture prediction of polycrystalline graphites. (author)

  8. Human emotions track changes in the acoustic environment.

    Science.gov (United States)

    Ma, Weiyi; Thompson, William Forde

    2015-11-24

    Emotional responses to biologically significant events are essential for human survival. Do human emotions lawfully track changes in the acoustic environment? Here we report that changes in acoustic attributes that are well known to interact with human emotions in speech and music also trigger systematic emotional responses when they occur in environmental sounds, including sounds of human actions, animal calls, machinery, or natural phenomena, such as wind and rain. Three changes in acoustic attributes known to signal emotional states in speech and music were imposed upon 24 environmental sounds. Evaluations of stimuli indicated that human emotions track such changes in environmental sounds just as they do for speech and music. Such changes not only influenced evaluations of the sounds themselves, they also affected the way accompanying facial expressions were interpreted emotionally. The findings illustrate that human emotions are highly attuned to changes in the acoustic environment, and reignite a discussion of Charles Darwin's hypothesis that speech and music originated from a common emotional signal system based on the imitation and modification of environmental sounds.

  9. A community engagement project in an undergraduate oceanography course to increase engagement and representation in marine science among high school students

    Science.gov (United States)

    Clark, C. D.; Prairie, J. C.; Walters, S. A.

    2016-02-01

    In the context of undergraduate education in oceanography, we are constantly striving for innovative ways to enhance student learning and enthusiasm for marine science. Community engagement is a form of experiential education that not only promotes a better understanding of concepts among undergraduate students but also allows them to interact with the community in a way that is mutually beneficial to both parties. Here I present on my experience in incorporating a community engagement project in my undergraduate physical oceanography course at the University of San Diego (USD) in collaboration with Mission Bay High School (MBHS), a local Title 1 International Baccalaureate high school with a high proportion of low-income students and students from underrepresented groups in STEM. As part of this project, the undergraduate students from my physical oceanography course were challenged to develop interactive workshops to present to the high school students at MBHS on some topic in oceanography. Prior to the workshops, the USD students met with the high school students at MBHS during an introductory meeting in which they could learn about each other's interests and backgrounds. The USD students then worked in teams of three to design a workshop proposal in which they outlined their plan for a workshop that was interactive and engaging, relying on demonstrations and activities rather than lecture. Each of the three teams then presented their workshops on separate days in the Mission Bay High School classroom. Finally, the USD students met again with the high school students at MBHS for a conclusion day in which both sets of students could discuss their experiences with the community engagement project. Through the workshop itself and a reflection essay written afterwards, the USD students learned to approach concepts in oceanography from a different perspective, and think about how student backgrounds can inform teaching these concepts. I will describe preliminary

  10. Software-based acoustical measurements

    CERN Document Server

    Miyara, Federico

    2017-01-01

    This textbook provides a detailed introduction to the use of software in combination with simple and economical hardware (a sound level meter with calibrated AC output and a digital recording system) to obtain sophisticated measurements usually requiring expensive equipment. It emphasizes the use of free, open source, and multiplatform software. Many commercial acoustical measurement systems use software algorithms as an integral component; however the methods are not disclosed. This book enables the reader to develop useful algorithms and provides insight into the use of digital audio editing tools to document features in the signal. Topics covered include acoustical measurement principles, in-depth critical study of uncertainty applied to acoustical measurements, digital signal processing from the basics, and metrologically-oriented spectral and statistical analysis of signals. The student will gain a deep understanding of the use of software for measurement purposes; the ability to implement software-based...

  11. Prototype acoustic resonance spectroscopy monitor

    International Nuclear Information System (INIS)

    Sinha, D.N.; Olinger, C.T.

    1996-03-01

    This report reports on work performed for the International Atomic Energy Agency (IAEA) through the Program Office for Technical Assistance (POTAS). In this work, we investigate possible applications of nondestructive acoustics measurements to facilitate IAEA safeguards at bulk processing facilities. Two different acoustic techniques for verifying the internal structure of a processing tank were investigated. During this effort we also examined two acoustic techniques for assessing the fill level within a processing tank. The fill-level measurements could be made highly portable and have an added safeguards advantage that they can also detect stratification of fill material. This later application may be particularly useful in confirming the absence of stratification in plutonium processing tanks before accountability samples are withdrawn

  12. Classroom acoustics: Three pilot studies

    Science.gov (United States)

    Smaldino, Joseph J.

    2005-04-01

    This paper summarizes three related pilot projects designed to focus on the possible effects of classroom acoustics on fine auditory discrimination as it relates to language acquisition, especially English as a second language. The first study investigated the influence of improving the signal-to-noise ratio on the differentiation of English phonemes. The results showed better differentiation with better signal-to-noise ratio. The second studied speech perception in noise by young adults for whom English was a second language. The outcome indicated that the second language learners required a better signal-to-noise ratio to perform equally to the native language participants. The last study surveyed the acoustic conditions of preschool and day care classrooms, wherein first and second language learning occurs. The survey suggested an unfavorable acoustic environment for language learning.

  13. 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.

  14. Performance of several viscothermal acoustic finite elements

    NARCIS (Netherlands)

    Kampinga, W.R.; Wijnant, Ysbrand H.; de Boer, Andries

    2010-01-01

    Viscothermal acoustics can be described by the linearized Navier Stokes equations. Besides inertia and compressibility, these equations take the heat conductivity and the viscosity of the medium (air) into account. These 'viscothermal' effects are significant in, for example, miniature acoustic

  15. 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...

  16. Subwoofer and nanotube butterfly acoustic flame extinction

    NARCIS (Netherlands)

    Aliev, Ali E.; Mayo, Nathanael K.; Baughman, Ray H.; Mills, Brent T.; Habtour, Ed

    2017-01-01

    Nonchemical flame control using acoustic waves from a subwoofer and a lightweight carbon nanotube thermoacoustic projector was demonstrated. The intent was to manipulate flame intensity, direction and propagation. The mechanisms of flame suppression using low frequency acoustic waves were discussed.

  17. High-power acoustic insult to living cultured cells as studied by high-frequency scanning acoustic microscopy

    Science.gov (United States)

    Miyasaka, Chiaki; Tittmann, Bernhard R.

    2002-06-01

    A plurality of articles discussing combined effects of acoustic high-pressure (mechanical factor) and heat (thermal factor) caused by acoustic vibration on biological tissues and cells has been published. Herein, we contribute the preliminary results describing the behavior of living human skin cells when separately applying shock waves and thermal insult to them. First, we gradually increased temperature of a culturing medium from 37.5 to 52 degree(s)C using the heat plate with temperature controller, and carried out in-situ observation of the cells grown on a substrate via the medium using a scanning acoustic microscope. Second, we provided the pressure using high power ultrasonic pulses generated by a laser induced ultrasonic shock wave system to the cells, wherein the pressure caused by the pulses was measured by a hydrophone, and wherein temperature was monitored by thermocouples. The cells were observed just after giving the impact. The difference between phenomena indicating cellular insult and injury (e.g., shrinkage or lift-off) were clearly visualized by the scanning acoustic microscope with frequency at 1.0 GHz.

  18. Historic perspective of the acoustic otoscope.

    Science.gov (United States)

    Walsh, F P; Cox, L C; MacDonald, C B

    1998-02-01

    The acoustic otoscope, originally called the acoustic reflectometer, was developed and produced by John and David Teele in the early 1980s. Since initial production, two different instrument versions have been developed by two separate companies. During the period of time in which the acoustic otoscope has been in production, there have been numerous studies reported with the two instrument versions. We provide a historic summary of the acoustic otoscope, summarize the pertinent studies, and address the contrasting results found in the literature.

  19. 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

  20. Acoustic target models and phenomenology

    Science.gov (United States)

    Neiswander, Paul R.; Kaiser, Stephen G.

    2000-07-01

    Ground-based and airborne acoustic systems often target vehicles that are powered by reciprocating internal combustion engines. Typically the far-field acoustic spectra of these vehicles are dominated by a few narrow spectral lines that are harmonically related. The dominant harmonics change with engine speed and also with emission angle. This paper describes a simple model that recreates some of this variability. The model breaks the far-field signature into two components: the generation of a train of pressure pulses at each exhaust outlet, and the radiation of sound pressures from the outlet(s) to the far field. Predictions are compared with field test data for two ground vehicles.

  1. Phase conjugation of acoustic beams

    Science.gov (United States)

    Bunkin, F. V.; Vlasov, D. V.; Kravtsov, Iu. A.

    The paper presents a classification of methods for the phase conjugation (PC) of wave fields of various physical natures on the basis of such nonliner interactions as stimulated scattering, and three- and four-wave interactions. Among the latter, attention is given to holographic (volume and surface) and parametric PC schemes, permitting PC with amplification. The possibility of developing phase-conjugated devices using acoustic PC devices on the basis of various nonlinear effects is considered. Experimental results pertaining to the PC of sound fields are presented, and possible applications of acoustic PC devices are indicated.

  2. 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...

  3. Measuring ship acoustic signatures against mine threat

    NARCIS (Netherlands)

    Jong, C.A.F. de; Quesson, B.A.J.; Ainslie, M.A.; Vermeulen, R.C.N.

    2012-01-01

    The NATO standard ‘AMP-15’ [1] provides procedures for the measurement and reporting of the acoustic signature of ships and for the establishment of acoustic signature goals to counter the naval mine threat. Measurements are carried out at dedicated shallow water acoustic ranges. Measurements

  4. Acoustic communication in plant–animal interactions

    NARCIS (Netherlands)

    Schöner, M.G.; Simon, R.; Schöner, C.R.

    2016-01-01

    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

  5. 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...

  6. The Acoustical Apparatus of Rudolph Koenig.

    Science.gov (United States)

    Greenslade, Thomas B., Jr.

    1992-01-01

    Discusses the history of Rudolph Koenig's contribution to the development of acoustical apparatus. Contributions include the clock fork to determine absolute acoustic frequencies, a forerunner of the oscilloscope called the manometric flame, and an acoustic interference apparatus used in the Fourier synthesis of musical sounds. (MDH)

  7. Application of holography in jet acoustic studies

    Indian Academy of Sciences (India)

    Source strength distribution on a jet boundary was obtained from measurements using the principle of acoustic holography. Measurements were conducted in an open field. Measurement of acoustic pressure on a cylindrical twodimensional contour located close to the vibrating jet boundary was used to obtain the acoustic ...

  8. Outdoor Acoustics as a General Discipline

    DEFF Research Database (Denmark)

    Rasmussen, Karsten Bo

    1999-01-01

    A tutorial paper exploring the characteristics of sound outdoors. Outdoor acoustics is contrasted to room acoustics. A number of important aspects of outdoor acoustics are exemplified and theoretical approaches are outlined. These are influence of ground impedance, influence of weather, screening...

  9. 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.

  10. RuCool Operational Oceanography: Using a Fleet of Autonomous Ocean Gliders

    Science.gov (United States)

    Graver, J.; Jones, C.; Glenn, S.; Kohut, J.; Schofield, O.; Roarty, H.; Aragon, D.; Kerfoot, J.; Haldeman, C.; Yan, A.

    2007-05-01

    At the Rutgers University Coastal Ocean Observation Lab (RU-COOL), we have constructed a shelf-wide ocean observatory to characterize the physical forcing of continental shelf primary productivity in the New York Bight (NYB). The system is anchored by four enabling technologies, which include the international constellation of ocean color satellites, multi-static high frequency long-range surface current radar, real-time telemetry moorings, and long duration autonomous underwater vehicles (AUVs). Operation of the observatory is through a centralized computer network dedicated to receiving, processing and visualizing the real-time data and then disseminating results to both field scientists and ocean forecasters over the World Wide Web. The system was designed to conduct cutting edge research requiring the addition of rapidly evolving technologies, and to serve society by providing sustained data delivered in real-time. Rutgers COOL continues to work closely with Webb Research Corporation (WRC) in testing and development of the Slocum underwater gliders and continues to apply Slocum gliders in field operations spanning the globe. The continued strong collaboration between WRC and Rutgers has led to advances in glider operations and applications. These include deployment/recovery techniques, improvements in durability and reliability, integrated sensors suites, salinity spike removal, and adaptive controls utilized to optimize mission goals and data return. The gliders have gathered numerous data sets including salt intrusions as seen off of New Jersey, plume tracking, biological water sample matching, and operation through Hurricane Ernesto in 2006. This talk will detail recent oceanographic experiments in which the fleet has been deployed and improvements in the operation of these novel robotic vehicles. These experiments, in locations around the world, have resulted in significant new work in operation of underwater gliders and have gathered new and unique data

  11. Modular microfluidic system for biological sample preparation

    Science.gov (United States)

    Rose, Klint A.; Mariella, Jr., Raymond P.; Bailey, Christopher G.; Ness, Kevin Dean

    2015-09-29

    A reconfigurable modular microfluidic system for preparation of a biological sample including a series of reconfigurable modules for automated sample preparation adapted to selectively include a) a microfluidic acoustic focusing filter module, b) a dielectrophoresis bacteria filter module, c) a dielectrophoresis virus filter module, d) an isotachophoresis nucleic acid filter module, e) a lyses module, and f) an isotachophoresis-based nucleic acid filter.

  12. Reverberant Acoustic Testing and Direct Field Acoustic Testing Acoustic Standing Waves and their Impact on Structural Responses

    Science.gov (United States)

    Kolaini, Ali R.; Doty, Benjamin; Chang, Zensheu

    2012-01-01

    The aerospace industry has been using two methods of acoustic testing to qualify flight hardware: (1) Reverberant Acoustic Test (RAT), (2) Direct Field Acoustic Test (DFAT). The acoustic field obtained by RAT is generally understood and assumed to be diffuse, expect below Schroeder cut-of frequencies. DFAT method of testing has some distinct advantages over RAT, however the acoustic field characteristics can be strongly affected by test setup such as the speaker layouts, number and location of control microphones and control schemes. In this paper the following are discussed based on DEMO tests performed at APL and JPL: (1) Acoustic wave interference patterns and acoustic standing waves, (2) The structural responses in RAT and DFAT.

  13. How the environment shapes animal signals: a test of the acoustic adaptation hypothesis in frogs.

    Science.gov (United States)

    Goutte, S; Dubois, A; Howard, S D; Márquez, R; Rowley, J J L; Dehling, J M; Grandcolas, P; Xiong, R C; Legendre, F

    2018-01-01

    Long-distance acoustic signals are widely used in animal communication systems and, in many cases, are essential for reproduction. The acoustic adaptation hypothesis (AAH) implies that acoustic signals should be selected for further transmission and better content integrity under the acoustic constraints of the habitat in which they are produced. In this study, we test predictions derived from the AAH in frogs. Specifically, we focus on the difference between torrent frogs and frogs calling in less noisy habitats. Torrents produce sounds that can mask frog vocalizations and constitute a major acoustic constraint on call evolution. We combine data collected in the field, material from scientific collections and the literature for a total of 79 primarily Asian species, of the families Ranidae, Rhacophoridae, Dicroglossidae and Microhylidae. Using phylogenetic comparative methods and including morphological and environmental potential confounding factors, we investigate putatively adaptive call features in torrent frogs. We use broad habitat categories as well as fine-scale habitat measurements and test their correlation with six call characteristics. We find mixed support for the AAH. Spectral features of torrent frog calls are different from those of frogs calling in other habitats and are related to ambient noise levels, as predicted by the AAH. However, temporal call features do not seem to be shaped by the frogs' calling habitats. Our results underline both the complexity of call evolution and the need to consider multiple factors when investigating this issue. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  14. Acoustic emission monitoring during welding

    International Nuclear Information System (INIS)

    Prine, D.W.

    1980-01-01

    Weld repair is a major cost item, particularly in the fabrication of heavy section weldments such as pressure vessels. A heavy section repair can frequently leave the weld with worse problems than the original flaw. These problems may include damage to weld microstructure as well as added residual stress. The removal of flaws through in-process repair can minimize these problems and certainly, the removal of one or two passes and their replacement with automatic welding procedure is considerably cheaper than a heavy section post weld repair. The major barrier to application of in-process repair is the lack of an effective in-process inspection procedure. In-process monitoring of Acoustic Emission shows great promise for providing this much needed tool. The successful application of acoustic emission to in-process weld monitoring requires that advanced signal processing and pattern recognition techniques be applied if the flaw related acoustic emission is to be separated from the overwhelming amount of background noise present in welding. GARD, INC. has studied the problem of applying in-process acoustic emission monitoring to weld inspection for over 9 years and has empirically developed AE signal processing techniques which allow typical weld flaws to be detected, located, and characterized. This paper discusses these techniques and describes a recent successful field test of a microcomputer based AE weld monitor in a nuclear fabrication plant. (author)

  15. 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.

  16. Shallow-Water Mud Acoustics

    Science.gov (United States)

    2015-09-30

    Ballard, Tom Muir , David Knobles, Kevin Lee, and Preston Wilson), and Naval Underwater Warfare Center-PC & NP (Kerry Commander, Danny Lim, David Burnett...K. M. Lee, and T. G. Muir , “Laboratory P- and S-wave measurements of a reconstituted muddy sediment with comparison to card-house theory,” J. Acoust

  17. 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...

  18. Acoustic Resonance in School Hallways

    Science.gov (United States)

    Bucki, Elliot; Nagle, Matthew; Smith, Pearson; Taylor, Ken

    2010-03-01

    This paper takes the theory of acoustic standing waves for air columns and applies it to school hallways. By utilizing an audio generator and power amplifier/speaker the authors set up an experiment in a school hallway and studied the resonant patterns created for a range of driving frequencies. Data describing the various mode structures are presented.

  19. 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...

  20. 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)

  1. Parvulescu Revisited: Small Tank Acoustics for Bioacousticians.

    Science.gov (United States)

    Rogers, Peter H; Hawkins, Anthony D; Popper, Arthur N; Fay, Richard R; Gray, Michael D

    2016-01-01

    Researchers often perform hearing studies on fish in small tanks. The acoustic field in such a tank is considerably different from the acoustic field that occurs in the animal's natural environment. The significance of these differences is magnified by the nature of the fish's auditory system where either acoustic pressure (a scalar), acoustic particle velocity (a vector), or both may serve as the stimulus. It is essential for the underwater acoustician to understand the acoustics of small tanks to be able to carry out valid auditory research in the laboratory and to properly compare and interpret the results of others.

  2. 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.

  3. Empirical mode decomposition for analyzing acoustical signals

    Science.gov (United States)

    Huang, Norden E. (Inventor)

    2005-01-01

    The present invention discloses a computer implemented signal analysis method through the Hilbert-Huang Transformation (HHT) for analyzing acoustical signals, which are assumed to be nonlinear and nonstationary. The Empirical Decomposition Method (EMD) and the Hilbert Spectral Analysis (HSA) are used to obtain the HHT. Essentially, the acoustical signal will be decomposed into the Intrinsic Mode Function Components (IMFs). Once the invention decomposes the acoustic signal into its constituting components, all operations such as analyzing, identifying, and removing unwanted signals can be performed on these components. Upon transforming the IMFs into Hilbert spectrum, the acoustical signal may be compared with other acoustical signals.

  4. The deep sea Acoustic Detection system AMADEUS

    International Nuclear Information System (INIS)

    Naumann, Christopher Lindsay

    2008-01-01

    As a part of the ANTARES neutrino telescope, the AMADEUS (ANTARES Modules for Acoustic Detection Under the Sea) system is an array of acoustical sensors designed to investigate the possibilities of acoustic detection of ultra-high energy neutrinos in the deep sea. The complete system will comprise a total of 36 acoustic sensors in six clusters on two of the ANTARES detector lines. With an inter-sensor spacing of about one metre inside the clusters and between 15 and 340 metres between the different clusters, it will cover a wide range of distances as will as provide a considerable lever arm for point source triangulation. Three of these clusters have already been deployed in 2007 and have been in operation since, currently yielding around 2GB of acoustic data per day. The remaining three clusters are scheduled to be deployed in May 2008 together with the final ANTARES detector line. Apart from proving the feasibility of operating an acoustic detection system in the deep sea, the main aim of this project is an in-depth survey of both the acoustic properties of the sea water and the acoustic background present at the detector site. It will also serve as a platform for the development and refinement of triggering, filtering and reconstruction algorithms for acoustic particle detection. In this presentation, a description of the acoustic sensor and read-out system is given, together with examples for the reconstruction and evaluation of the acoustic data.

  5. Diversity of biomedical applications of acoustic radiation force.

    Science.gov (United States)

    Sarvazyan, Armen

    2010-02-01

    This manuscript is a summary of the paper presented at the ICU'2009 on biomedical applications of acoustic radiation force with emphasis on emerging applications in microfluidics, biotechnology, biosensors and assessment of the skeletal system. In this brief overview of current and projected applications of radiation force, no detailed description of the experiments illustrating particular applications are given as this would result in a far different and longer paper. Various mechanisms of acoustic radiation force generations and their biomedical applications are considered. These mechanisms include: (a) change in the density of energy of the propagating wave due to absorption and scattering; (b) spatial variations of energy density in standing acoustic waves; (c) reflection from inclusions, walls or other interfaces; and (d) spatial variations in propagation velocity. The widest area of biomedical applications of radiation force is related to medical diagnostics, to assessing viscoelastic properties of biological tissues and fluids, and specifically to elasticity imaging. Another actively explored area is related to manipulation of biological cells and particles in standing ultrasonic wave fields. There are several poorly explored areas of potential biomedical applications of ultrasound radiation force. A promising area of biomedical application of ultrasound radiation force is stirring and mixing of microvolumes of liquids in microfluidics and in various biotechnological application where diffusion rate is the main factor limiting the efficiency of the process of interest. A new technique, called "swept frequency method", based on the use of radiation force in the standing acoustic wave for microstirring of liquids is described. The potential applications of the ultrasound radiation force for assessment of skeletal system, where conventional bone ultrasonometry are inapplicable are considered.

  6. Evolution of acoustic and visual signals in Asian barbets.

    Science.gov (United States)

    Gonzalez-Voyer, A; den Tex, R-J; Castelló, A; Leonard, J A

    2013-03-01

    The study of animal communication systems is an important step towards gaining greater understanding of the processes influencing diversification because signals often play an important role in mate choice and can lead to reproductive isolation. Signal evolution can be influenced by a diversity of factors such as biophysical constraints on the emitter, the signalling environment, or selection to avoid heterospecific matings. Furthermore, because signals can be costly to produce, trade-offs may exist between different types of signals. Here, we apply phylogenetic comparative analyses to study the evolution of acoustic and visual signals in Asian barbets, a clade of non-Passerine, forest-dependent birds. Our results suggest that evolution of acoustic and visual signals in barbets is influenced by diverse factors, such as morphology and signalling environment, suggesting a potential effect of sensory drive. We found no trade-offs between visual and acoustic signals. Quite to the contrary, more colourful species sing significantly longer songs. Song characteristics presented distinct patterns of evolution. Song frequency diverged early on and the rate of evolution of this trait appears to be constrained by body size. On the other hand, characteristics associated with length of the song presented evidence for more recent divergence. Finally, our results indicate that there is a spatial component to the evolution of visual signals, and that visual signals are more divergent between closely related taxa than acoustic signals. Hence, visual signals in these species could play a role in speciation or reinforcement of reproductive isolation following secondary contacts. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  7. Granular acoustic switches and logic elements

    Science.gov (United States)

    Li, Feng; Anzel, Paul; Yang, Jinkyu; Kevrekidis, Panayotis G.; Daraio, Chiara

    2014-10-01

    Electrical flow control devices are fundamental components in electrical appliances and computers; similarly, optical switches are essential in a number of communication, computation and quantum information-processing applications. An acoustic counterpart would use an acoustic (mechanical) signal to control the mechanical energy flow through a solid material. Although earlier research has demonstrated acoustic diodes or circulators, no acoustic switches with wide operational frequency ranges and controllability have been realized. Here we propose and demonstrate an acoustic switch based on a driven chain of spherical particles with a nonlinear contact force. We experimentally and numerically verify that this switching mechanism stems from a combination of nonlinearity and bandgap effects. We also realize the OR and AND acoustic logic elements by exploiting the nonlinear dynamical effects of the granular chain. We anticipate these results to enable the creation of novel acoustic devices for the control of mechanical energy flow in high-performance ultrasonic devices.

  8. Handbook of Signal Processing in Acoustics

    CERN Document Server

    Havelock, David; Vorländer, Michael

    2009-01-01

    The Handbook of Signal Processing in Acoustics presents signal processing as it is practiced in the field of acoustics. The Handbook is organized by areas of acoustics, with recognized leaders coordinating the self-contained chapters of each section. It brings together a wide range of perspectives from over 100 authors to reveal the interdisciplinary nature of signal processing in acoustics. Success in acoustic applications often requires juggling both the acoustic and the signal processing parameters of the problem. This handbook brings the key issues from both into perspective and is complementary to other reference material on the two subjects. It is a unique resource for experts and practitioners alike to find new ideas and techniques within the diversity of signal processing in acoustics.

  9. Measurements of acoustic properties for thin films

    International Nuclear Information System (INIS)

    Kushibiki, J.; Maehara, H.; Chubachi, N.

    1982-01-01

    A measurement method for determining thin-film acoustic properties, such as characteristic acoustic impedance, sound velocity, density, and stiffness constant, is developed with a simple measurement principle and high measurement accuracy. The acoustic properties are determined from a maximum reflection loss and a center frequency obtained through a frequency response of the reflection loss for an acoustic transmission line composed of a sapphire/film/water system by using the acoustic pulse mode measurement system in the UHF range. The determination of the acoustic properties is demonstrated for sputtered fused quartz film, low-expansion borosilicate glass films, and chalcogenide glass films of evaporated As 2 S 3 and As 2 Se 3 , within the measurement accuracy around 1--2%. It is also found that the acoustic properties of thin films are generally different from those of bulk materials, depending on the fabrication techniques and conditions

  10. Shape optimization: Good looks and acoustics too!

    Science.gov (United States)

    D'Antonio, Peter; Cox, Trevor J.; Haas, Steve

    2003-04-01

    One of the challenges in the architectural acoustic design of museums and other public spaces is to develop contemporary scattering surfaces that complement contemporary architecture in the way that statuary, coffered ceilings, columns, and relief ornamentation complemented classic architecture. Often acoustic surfaces satisfy the acoustics, but may or may not satisfy the aesthetics. One approach that has been successful employs a combination of boundary element and multidimensional optimization techniques. The architect supplies the desired shape motif and the acoustician supplies the acoustical performance requirements. The optimization program then provides an Arcousthetic surface, which simultaneously satisfies the architecture, the acoustics, and the aesthetics. The program can be used with diffusive or diffsorptive surfaces. Photos of installations using these acoustic tools and a description of the design of the National Museum of the American Indian will also be presented to illustrate the usefulness of these devices and their impact on architectural acoustics.

  11. Computer simulations enhance experimental demonstrations in the underwater acoustics and sonar course

    Science.gov (United States)

    Korman, Murray S.

    2002-11-01

    Underwater acoustics and sonar (SP411) is a 3 hour course that is offered to midshipmen in their senior year. Typically, general science and oceanography majors, totaling 110 students/yr, enroll. Since this course is offered without a lab, the ''in class'' experience has been enhanced with the development (over many years) of our demo carts and computer workstations which surround the classroom. In a studio classroom atmosphere, students perform a variety of experiments in small groups. How can scientific visualizations best develop learning of complex interactions? Two examples are presented. PC-IMAT (personal curriculum interactive multisensor analysis training) simulations of multielement array steering support the theory and enhance the experiments that are performed in class such as the two-element array. Mathematica simulations involving the programming and animation of a point source in a rigid-rigid infinite parallel wave guide are used to stress the method of images, superposition, group and phase velocity and far-field modal pattern that is observed as a function of depth and source frequency. Later, students have fun using a ripple tank with an eye dropper to generate a point source between two adjustable parallel boundaries, and their understanding of ''underwater sound'' is greatly enhanced.

  12. Systems Biology

    Indian Academy of Sciences (India)

    IAS Admin

    Systems biology seeks to study biological systems as a whole, contrary to the reductionist approach that has dominated biology. Such a view of biological systems emanating from strong foundations of molecular level understanding of the individual components in terms of their form, function and interactions is promising to ...

  13. Acoustic Environment Simulation Study; Acoustic Intrusion Sensor Performance.

    Science.gov (United States)

    1983-01-01

    generation of transients. 10,000. 13. Software for stastistical record keeping. 7,500. Note that no allowance is made here for additional racks or backplanes...sAcoustic Instrusion Sensor Performance Date Jan 83 I 0.1. TERMINOLOGY ATSA APPLIED TIME SERIES ANALYSIS, R. K. Otnes and L. Enochson, Wiley Interscience...verif- ication of the procedures. The terminology used in this report is essentially the same as that in APPLIED TIME SERIES ANALYSIS, VOLUME I, by Robert

  14. 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.

  15. Acoustic spin pumping in magnetoelectric bulk acoustic wave resonator

    Energy Technology Data Exchange (ETDEWEB)

    Polzikova, N. I., E-mail: polz@cplire.ru; Alekseev, S. G.; Pyataikin, I. I.; Kotelyanskii, I. M.; Luzanov, V. A.; Orlov, A. P. [Kotel’nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences, Mokhovaya 11, building 7, Moscow, 125009 (Russian Federation)

    2016-05-15

    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.

  16. Acoustic design method of ship's cabin based on geometrical acoustics

    Directory of Open Access Journals (Sweden)

    FENG Aijing

    2017-08-01

    Full Text Available In light of the question of how to select the best noise control position and measures in the large noise transmission path of the cabins of a ship, based on the acoustic ray-tracing method in the theory of geometrical acoustics, and by considering the effect of the sound transmission of the bulkhead, this paper proposes the sound line search method. It is used to calculate the sound pressure of a ship's cabin, allowing the sound field distribution of multiple compartments to be simulated. The paper proposes a sound ray-searching method in which the acoustic sensitivity of different positions of the bulkhead to the noise of the target cabin is calculated by searching for the sound ray passing the target cabin. According to this, a cabin noise reduction plan can be designed to optimize medium and high frequency cabin noise. With this method, the noise of a typical cabin can be optimized and reduced by 7.3 dB. Through comparative analysis with the statistical energy method, it is proven that the method is feasible and can guide the refined design of noise reduction in ships' cabins.

  17. Hidden acoustic information revealed by intentional nonlinearity

    Science.gov (United States)

    Dowling, David R.

    2017-11-01

    Acoustic waves are omnipresent in modern life and are well described by the linearized equations of fluid dynamics. Once generated, acoustic waves carry and collect information about their source and the environment through which they propagate, respectively, and this information may be retrieved by analyzing recordings of these waves. Because of this, acoustics is the primary means for observation, surveillance, reconnaissance, and remote sensing in otherwise opaque environments, such as the Earth's oceans and crust, and the interior of the human body. For such information-retrieval tasks, acoustic fields are nearly always interrogated within their recorded frequency range or bandwidth. However, this frequency-range restriction is not general; acoustic fields may also carry (hidden) information at frequencies outside their bandwidth. Although such a claim may seem counter intuitive, hidden acoustic-field information can be revealed by re-introducing a marquee trait of fluid dynamics: nonlinearity. In particular, an intentional quadratic nonlinearity - a form of intra-signal heterodyning - can be used to obtain acoustic field information at frequencies outside a recorded acoustic field's bandwidth. This quadratic nonlinearity enables a variety of acoustic remote sensing applications that were long thought to be impossible. In particular, it allows the detrimental effects of sparse recordings and random scattering to be suppressed when the original acoustic field has sufficient bandwidth. In this presentation, the topic is developed heuristically, with a just brief exposition of the relevant mathematics. Hidden acoustic field information is then revealed from simulated and measured acoustic fields in simple and complicated acoustic environments involving frequencies from a few Hertz to more than 100 kHz, and propagation distances from tens of centimeters to hundreds of kilometers. Sponsored by ONR, NAVSEA, and NSF.

  18. Cooperative OFDM underwater acoustic communications

    CERN Document Server

    Cheng, Xilin; Cheng, Xiang

    2016-01-01

    Following underwater acoustic channel modeling, this book investigates the relationship between coherence time and transmission distances. It considers the power allocation issues of two typical transmission scenarios, namely short-range transmission and medium-long range transmission. For the former scenario, an adaptive system is developed based on instantaneous channel state information. The primary focus is on cooperative dual-hop orthogonal frequency division multiplexing (OFDM). This book includes the decomposed fountain codes designed to enable reliable communications with higher energy efficiency. It covers the Doppler Effect, which improves packet transmission reliability for effective low-complexity mirror-mapping-based intercarrier interference cancellation schemes capable of suppressing the intercarrier interference power level. Designed for professionals and researchers in the field of underwater acoustic communications, this book is also suitable for advanced-level students in electrical enginee...

  19. Acoustic biotelemetry from Slocum Gliders

    Science.gov (United States)

    Oliver, M. J.; Haulsee, D.; Breece, M.; Kohut, J. T.; Fox, D. A.; Wetherbee, B.; Cimino, M. A.

    2016-02-01

    The integration of biotelemetry and Slocum electric gliders presents new opportunities and challenges for interpreting the relationship between acoustically telemetered animals and the environment. Slocum gliders are able to stay in the field for extended periods (> 90 days) while collecting high-resolution data that can be used to reconstruct subsurface habitats. Here we present several case studies that compare integrated and externally mounted acoustic receiver technologies aboard Slocum gliders, compare detection efficiency between coastal arrays and Slocum gliders, investigate signal detectability in coastal habitats, and identify habitat associations of migrating species. Our studies leverage several ongoing tagging efforts, and would not be possible without a highly collaborative biotelemetry community. Slocum gliders are a robust technology that augments existing biotelemetry arrays and enable dynamic sampling of environments that extend beyond the feasibility of stationary arrays. The platforms are ideal for integrating biotelemetry into ocean observing and can provide ecologically relevant habitat associations that assist in the management of telemetered species.

  20. Oscillating nonlinear acoustic shock waves

    DEFF Research Database (Denmark)

    Gaididei, Yuri; Rasmussen, Anders Rønne; Christiansen, Peter Leth

    2016-01-01

    We investigate oscillating shock waves in a tube using a higher order weakly nonlinear acoustic model. The model includes thermoviscous effects and is non isentropic. The oscillating shock waves are generated at one end of the tube by a sinusoidal driver. Numerical simulations show...... that at resonance a stationary state arise consisting of multiple oscillating shock waves. Off resonance driving leads to a nearly linear oscillating ground state but superimposed by bursts of a fast oscillating shock wave. Based on a travelling wave ansatz for the fluid velocity potential with an added 2'nd order...... polynomial in the space and time variables, we find analytical approximations to the observed single shock waves in an infinitely long tube. Using perturbation theory for the driven acoustic system approximative analytical solutions for the off resonant case are determined....

  1. 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...... in the currently applied measurement system allows for a minimum detectable mass of 0.5 fg in air.......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...

  2. [Acoustic information in snoring noises].

    Science.gov (United States)

    Janott, C; Schuller, B; Heiser, C

    2017-02-01

    More than one third of all people snore regularly. Snoring is a common accompaniment of obstructive sleep apnea (OSA) and is often disruptive for the bed partner. This work gives an overview of the history of and state of research on acoustic analysis of snoring for classification of OSA severity, detection of obstructive events, measurement of annoyance, and identification of the sound excitation location. Based on these objectives, searches were conducted in the literature databases PubMed and IEEE Xplore. Publications dealing with the respective objectives according to title and abstract were selected from the search results. A total of 48 publications concerning the above objectives were considered. The limiting factor of many studies is the small number of subjects upon which the analyses are based. Recent research findings show promising results, such that acoustic analysis may find a place in the framework of sleep diagnostics, thus supplementing the recognized standard methods.

  3. Acoustic emission linear pulse holography

    International Nuclear Information System (INIS)

    Collins, H.D.; Busse, L.J.; Lemon, D.K.

    1983-01-01

    This paper describes the emission linear pulse holography which produces a chronological linear holographic image of a flaw by utilizing the acoustic energy emitted during crack growth. A thirty two point sampling array is used to construct phase-only linear holograms of simulated acoustic emission sources on large metal plates. The concept behind the AE linear pulse holography is illustrated, and a block diagram of a data acquisition system to implement the concept is given. Array element spacing, synthetic frequency criteria, and lateral depth resolution are specified. A reference timing transducer positioned between the array and the inspection zone and which inititates the time-of-flight measurements is described. The results graphically illustrate the technique using a one-dimensional FFT computer algorithm (ie. linear backward wave) for an AE image reconstruction

  4. Marine Mammal Acoustic Monitoring and Habitat Investigation, Southern California Offshore Region

    Science.gov (United States)

    2009-06-01

    in the acoustic signals of beaked whales at Cross Seamount . Biology Letters 4(2): 208-211. KRYSL, P., T. W. CRANFORD, and J. A. HILDEBRAND...Conference on the Biology of Marine Mammals. Cape Town, South Africa. HENDERSON, E. E., J. A. HILDEBRAND, J. BARLOW, K. A. FORNEY, J. CALAMBOKIDIS...estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources, gathering and maintaining the

  5. Nonlinear positron acoustic solitary waves

    International Nuclear Information System (INIS)

    Tribeche, Mouloud; Aoutou, Kamel; Younsi, Smain; Amour, Rabia

    2009-01-01

    The problem of nonlinear positron acoustic solitary waves involving the dynamics of mobile cold positrons is addressed. A theoretical work is presented to show their existence and possible realization in a simple four-component plasma model. The results should be useful for the understanding of the localized structures that may occur in space and laboratory plasmas as new sources of cold positrons are now well developed.

  6. Acoustic habitat of an oceanic archipelago in the Southwestern Atlantic

    Science.gov (United States)

    Bittencourt, Lis; Barbosa, Mariana; Secchi, Eduardo; Lailson-Brito, José; Azevedo, Alexandre

    2016-09-01

    Underwater soundscapes can be highly variable, and in natural conditions are often dominated by biological signals and physical features of the environment. Few studies, however, focused on oceanic islands soundscapes. Islands in the middle of ocean basins can provide a good example of how untouched marine soundscapes are. Autonomous acoustic recordings were carried out in two different seasons in Trindade-Martin Vaz Archipelago, Southwestern Atlantic, providing nearly continuous data for both periods. Sound levels varied daily and between seasons. During summer, higher frequencies were noisier than lower frequencies, with snapping shrimp being the dominating sound source. During winter, lower frequencies were noisier than higher frequencies due to humpback whale constant singing. Biological signal detection had a marked temporal pattern, playing an important role in the soundscape. Over 1000 humpback whale sounds were detected hourly during winter. Fish vocalizations were detected mostly during night time during both summer and winter. The results show an acoustic habitat dominated by biological sound sources and highlight the importance of the island to humpback whales in winter.

  7. Acoustic telemetry and fisheries management

    Science.gov (United States)

    Crossin, Glenn T.; Heupel, Michelle R.; Holbrook, Christopher; Hussey, Nigel E.; Lowerre-Barbieri, Susan K; Nguyen, Vivian M.; Raby, Graham D.; Cooke, Steven J.

    2017-01-01

    This paper reviews the use of acoustic telemetry as a tool for addressing issues in fisheries management, and serves as the lead to the special Feature Issue of Ecological Applications titled “Acoustic Telemetry and Fisheries Management”. Specifically, we provide an overview of the ways in which acoustic telemetry can be used to inform issues central to the ecology, conservation, and management of exploited and/or imperiled fish species. Despite great strides in this area in recent years, there are comparatively few examples where data have been applied directly to influence fisheries management and policy. We review the literature on this issue, identify the strengths and weaknesses of work done to date, and highlight knowledge gaps and difficulties in applying empirical fish telemetry studies to fisheries policy and practice. We then highlight the key areas of management and policy addressed, as well as the challenges that needed to be overcome to do this. We conclude with a set of recommendations about how researchers can, in consultation with stock assessment scientists and managers, formulate testable scientific questions to address and design future studies to generate data that can be used in a meaningful way by fisheries management and conservation practitioners. We also urge the involvement of relevant stakeholders (managers, fishers, conservation societies, etc.) early on in the process (i.e. in the co-creation of research projects), so that all priority questions and issues can be addressed effectively.

  8. Adjoint modeling for acoustic inversion

    Science.gov (United States)

    Hursky, Paul; Porter, Michael B.; Cornuelle, B. D.; Hodgkiss, W. S.; Kuperman, W. A.

    2004-02-01

    The use of adjoint modeling for acoustic inversion is investigated. An adjoint model is derived from a linearized forward propagation model to propagate data-model misfit at the observation points back through the medium to the medium perturbations not being accounted for in the model. This adjoint model can be used to aid in inverting for these unaccounted medium perturbations. Adjoint methods are being applied to a variety of inversion problems, but have not drawn much attention from the underwater acoustic community. This paper presents an application of adjoint methods to acoustic inversion. Inversions are demonstrated in simulation for both range-independent and range-dependent sound speed profiles using the adjoint of a parabolic equation model. Sensitivity and error analyses are discussed showing how the adjoint model enables calculations to be performed in the space of observations, rather than the often much larger space of model parameters. Using an adjoint model enables directions of steepest descent in the model parameters (what we invert for) to be calculated using far fewer modeling runs than if a forward model only were used.

  9. Method for acoustic signal detection

    International Nuclear Information System (INIS)

    Blalock, S.E.

    1980-01-01

    The disclosure relates to a method and apparatus for acoustic signal detection, adapted for use in acoustic velocity well logging to measure the difference in transit times of an acoustic signal between a transmitter and two or more receivers. In a preferred embodiment of the present invention two timing measurements of the signal arriving at each of two receivers may be made by activating zero crossing detectors at the arrival of the first negative and first positive half-cycles at each receiver. A transit time is calculated from the zero crossing times following the first negative half-cycle. This first transit time may be checked for accuracy by comparing the first transit time with a second transit time calculated from zero crossing times following the first positive half-cycles, by comparing the first transit time to a previously measured transit time and/or by detecting the order of arrival of the negative and positive half-cycles to determine whether the half-cycles have been detected out of sequence at either receiver. Should the first transit time be determined to be inaccurate, the previously measured transit time or the second transit time may be substituted therefor

  10. Progress report from Duke University - Cooperative Research and Training Program in Biological Oceanography from 01 July 1965 to 30 June 1966 (NODC Accession 7200405)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The progress report covers the period from 01 July 1965 to 30 June 1966. The main purpose of the report is to provide cooperating investigators with field and cruise...

  11. AN ASSESSMENT OF THE ECOLOGICAL CONDITION OF COASTAL WATERS SURROUNDING THE GULF OF MEXICO IAPSO INTERNATIONAL ASSOCIATION FOR BIOLOGICAL OCEANOGRAPHY MEETING, LA PLATA, ARGENTINA, OCTOBER 2001

    Science.gov (United States)

    Assessment of the Ecological Condition of Coastal Waters Surrounding the Gulf of Mexico (Abstract). To be presented at the Joint IAPSO/IABO Assembly: 2001 An Ocean Odyssey, 21-26 October 2001, Mar del Plata, Argentina. 1 p. (ERL,GB R844).The purpose of the Environmental ...

  12. Biological computation

    CERN Document Server

    Lamm, Ehud

    2011-01-01

    Introduction and Biological BackgroundBiological ComputationThe Influence of Biology on Mathematics-Historical ExamplesBiological IntroductionModels and Simulations Cellular Automata Biological BackgroundThe Game of Life General Definition of Cellular Automata One-Dimensional AutomataExamples of Cellular AutomataComparison with a Continuous Mathematical Model Computational UniversalitySelf-Replication Pseudo Code Evolutionary ComputationEvolutionary Biology and Evolutionary ComputationGenetic AlgorithmsExample ApplicationsAnalysis of the Behavior of Genetic AlgorithmsLamarckian Evolution Genet

  13. Nonlinear acoustic wave equations with fractional loss operators.

    Science.gov (United States)

    Prieur, Fabrice; Holm, Sverre

    2011-09-01

    Fractional derivatives are well suited to describe wave propagation in complex media. When introduced in classical wave equations, they allow a modeling of attenuation and dispersion that better describes sound propagation in biological tissues. Traditional constitutive equations from solid mechanics and heat conduction are modified using fractional derivatives. They are used to derive a nonlinear wave equation which describes attenuation and dispersion laws that match observations. This wave equation is a generalization of the Westervelt equation, and also leads to a fractional version of the Khokhlov-Zabolotskaya-Kuznetsov and Burgers' equations. © 2011 Acoustical Society of America

  14. Evanescent Acoustic Wave Scattering by Targets and Diffraction by Ripples Graduate Traineeship Award in Ocean Acoustics

    National Research Council Canada - National Science Library

    Osterhoudt, Curtis F; Marston, Philip L

    2007-01-01

    .... The purpose of his research was to improve the understanding of the way that acoustic evanescent waves interact with targets buried in sediments in situations encountered in underwater acoustics...

  15. Acoustic communication for Maya Autonomous Underwater Vehicle - performance evaluation of acoustic modem

    Digital Repository Service at National Institute of Oceanography (India)

    Afzulpurkar, S.; Maurya, P.; Navelkar, G.S.; Desa, E.S.; Mascarenhas, A.A.M.Q.; Dabholkar, N.A.; Madhan, R.; Prabhudesai, S.P.

    traffic. This necessitates monitoring the AUV status and data quality through an acoustic link which needs to perform reliably under such conditions, at long range. To address these situations partially, acoustic communication capability is planned...

  16. Acoustic wave science realized by metamaterials.

    Science.gov (United States)

    Lee, Dongwoo; Nguyen, Duc Minh; Rho, Junsuk

    2017-01-01

    Artificially structured materials with unit cells at sub-wavelength scale, known as metamaterials, have been widely used to precisely control and manipulate waves thanks to their unconventional properties which cannot be found in nature. In fact, the field of acoustic metamaterials has been much developed over the past 15 years and still keeps developing. Here, we present a topical review of metamaterials in acoustic wave science. Particular attention is given to fundamental principles of acoustic metamaterials for realizing the extraordinary acoustic properties such as negative, near-zero and approaching-infinity parameters. Realization of acoustic cloaking phenomenon which is invisible from incident sound waves is also introduced by various approaches. Finally, acoustic lenses are discussed not only for sub-diffraction imaging but also for applications based on gradient index (GRIN) lens.

  17. Acoustic levitation of a large solid sphere

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Marco A. B., E-mail: marcobrizzotti@gmail.com [Institute of Physics, University of São Paulo, São Paulo 05508-090 (Brazil); Bernassau, Anne L. [School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Adamowski, Julio C. [Department of Mechatronics and Mechanical Systems Engineering, Escola Politécnica, University of São Paulo, São Paulo 05508-030 (Brazil)

    2016-07-25

    We demonstrate that acoustic levitation can levitate spherical objects much larger than the acoustic wavelength in air. The acoustic levitation of an expanded polystyrene sphere of 50 mm in diameter, corresponding to 3.6 times the wavelength, is achieved by using three 25 kHz ultrasonic transducers arranged in a tripod fashion. In this configuration, a standing wave is created between the transducers and the sphere. The axial acoustic radiation force generated by each transducer on the sphere was modeled numerically as a function of the distance between the sphere and the transducer. The theoretical acoustic radiation force was verified experimentally in a setup consisting of an electronic scale and an ultrasonic transducer mounted on a motorized linear stage. The comparison between the numerical and experimental acoustic radiation forces presents a good agreement.

  18. Atlantic Oceanography. Volume 1

    Science.gov (United States)

    1978-08-01

    on GILLISS , and Leg 2 on ALVIN. A portion of the salaries in this budget and Items 1, 2, and 3 of Expendables are for this service. Items 4 and 5 in...load the major instrument systems aboard the R/V GILLISS , which is based in Miami. (OPERATIONS BUDGET) The funds requested in this budget are also...transport this equipment to Miami to be loaded on board the GILLISS , and funds have been requested from I.D.O.E. to ship the equipment back to Woods Hole

  19. Oceanography Branch Plankton Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shelf-wide Research Vessel Surveys are conducted 4-8 times per year over the continental shelf from Cape Hatteras, North Carolina to Cape Sable, Nova Scotia, using...

  20. Oceanography of marginal seas

    Digital Repository Service at National Institute of Oceanography (India)

    DileepKumar, M.

    The North Indian Ocean consists of three marginal seas; The Persian Gulf and the Red Sea in the west and the Andaman Sea in the east. Oceanographic features of these semi-enclosed basins have been discussed in this article. While circulation...

  1. Acoustic experience shapes female mate choice in field crickets

    Science.gov (United States)

    Bailey, Nathan W; Zuk, Marlene

    2008-01-01

    Female choice can drive the evolution of extravagant male traits. In invertebrates, the influence of prior social experience on female choice has only recently been considered. To better understand the evolutionary implications of experience-mediated plasticity in female choice, we investigated the effect of acoustic experience during rearing on female responsiveness to male song in the field cricket Teleogryllus oceanicus. Acoustic experience has unique biological relevance in this species: a morphological mutation has rendered over 90 per cent of males on the Hawaiian island of Kauai silent in fewer than 20 generations, impeding females' abilities to locate potential mates. Females reared in silent conditions mimicking Kauai were less discriminating of male calling song and more responsive to playbacks, compared with females that experienced song during rearing. Our results to our knowledge, are the first demonstration of long-term effects of acoustic experience in an arthropod, and suggest that female T. oceanicus may be able to compensate for the reduced availability of long-range male sexual signals by increasing their responsiveness to the few remaining signallers. Understanding the adaptive significance of experience-mediated plasticity in female choice provides insight into processes that facilitate rapid evolutionary change and shape sexual selection pressure in natural populations. PMID:18700205

  2. Application of acoustic microscopy to assessment of cardiovascular biomechanics

    Science.gov (United States)

    Saijo, Yoshifumi; Sasaki, Hidehiko; Nitta, Shin-ichi; Tanaka, Motonao; Joergensen, Claus S.; Falk, Erling

    2002-11-01

    Acoustic microscopy provides information on physical and mechanical properties of biological tissues, while optical microscopy with various staining techniques provides chemical properties. The biomechanics of tissues is especially important in cardiovascular system because its pathophysiology is closely related with mechanical stresses such as blood pressure or blood flow. A scanning acoustic microscope (SAM) system with tone-burst ultrasound in the frequency range of 100-200 MHz has been developed, and attenuation and sound speed of tissues have been measured. In human coronary arteries, attenuation and sound speed were high in calcification and collagen, while both values were low in smooth muscle and lipid. Another SAM system with 800-MHz-1.3-GHz ultrasound was applied for aortas of Apo-E deficient mouse, which is known to develop atherosclerosis. Attenuation of ultrasound was significantly higher in type 1 collagen compared to type 3 collagen. Recently, a new type FFT-SAM using a single-pulse, broadband frequency range ultrasound (20-150 MHz) has been developed. Cardiac allograft was observed by FFT-SAM and the acoustic properties were able to grade allograft rejection. SAM provides very useful information for assessing cardiovascular biomechanics and for understanding normal and abnormal images of clinical ultrasound.

  3. The Development of SONAR as a Tool in Marine Biological Research in the Twentieth Century

    Directory of Open Access Journals (Sweden)

    John A. Fornshell

    2013-01-01

    Full Text Available The development of acoustic methods for measuring depths and ranges in the ocean environment began in the second decade of the twentieth century. The two world wars and the “Cold War” produced three eras of rapid technological development in the field of acoustic oceanography. By the mid-1920s, researchers had identified echoes from fish, Gadus morhua, in the traces from their echo sounders. The first tank experiments establishing the basics for detection of fish were performed in 1928. Through the 1930s, the use of SONAR as a means of locating schools of fish was developed. The end of World War II was quickly followed by the advent of using SONAR to track and hunt whales in the Southern Ocean and the marketing of commercial fish finding SONARs for use by commercial fisherman. The “deep scattering layer” composed of invertebrates and fish was discovered in the late 1940s on the echo sounder records. SONARs employing high frequencies, broadband, split beam, and multiple frequencies were developed as methods for the detection, quantification and identification of fish and invertebrates. The study of fish behavior has seen some use of passive acoustic techniques. Advancements in computer technology have been important throughout the last four decades of the twentieth century.

  4. Feature selection for multimodal: acoustic Event detection

    OpenAIRE

    Butko, Taras

    2011-01-01

    Acoustic Event Detection  The detection of the Acoustic Events (AEs) naturally produced in a meeting room may help to describe the human and social activity. The automatic description of interactions between humans and environment can be useful for providing: implicit assistance to the people inside the room, context-aware and content-aware information requiring a minimum of human attention or interruptions, support for high-level analysis of the underlying acoustic scene, etc. On the othe...

  5. Acoustic 3D imaging of dental structures

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, D.K. [Lawrence Livermore National Lab., CA (United States); Hume, W.R. [California Univ., Los Angeles, CA (United States); Douglass, G.D. [California Univ., San Francisco, CA (United States)

    1997-02-01

    Our goals for the first year of this three dimensional electodynamic imaging project was to determine how to combine flexible, individual addressable; preprocessing of array source signals; spectral extrapolation or received signals; acoustic tomography codes; and acoustic propagation modeling code. We investigated flexible, individually addressable acoustic array material to find the best match in power, sensitivity and cost and settled on PVDF sheet arrays and 3-1 composite material.

  6. Experimental Acoustic Evaluation of an Auditorium

    Directory of Open Access Journals (Sweden)

    Marina Dana Ţopa

    2012-01-01

    Full Text Available The paper presents a case history: the acoustical analysis of a rectangular auditorium. The following acoustical parameters were evaluated: early decay time, reverberation time, clarity, definition, and center time. The excitation signal was linear sweep sine and additional analysis was carried out: peak-to-noise ratio, reverberation time for empty and occupied room, standard deviation of acoustical parameters, diffusion, and just noticeable differences analysis. Conclusions about room’s destination and modeling were drawn in the end.

  7. Canada Basin Acoustic Propagation Experiment (CANAPE)

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Canada Basin Acoustic Propagation Experiment (CANAPE...about Arctic acoustics during the Cold War is now obsolete. The goal of the Canada Basin Acoustic Propagation Experiment (CANAPE) is to determine the...Canada Basin (McLaughlin et al., 2011). These changing conditions make the Canada Basin an ideal location to test the hypothesis put forward by P

  8. North Pacific Acoustic Laboratory: Deep Water Acoustic Propagation in the Philippine Sea

    Science.gov (United States)

    2016-06-21

    Acoustic Laboratory: Deep Water Acoustic Propagation in the Philippine Sea 5b. GRANT NUMBER NOOO 14-12-1 -0226 5c. PROGRAM ELEMENT NUMBER 6...based on data from the 2009-20 I I NPAL Philippine Sea experiments funded by ONR Grant NOOO 14-08-1-0840 , Fourteen of these publi cations appeared in...North Pacific Acoustic Laboratory: Deep Water Acoustic Propagation in the Philippine Sea ONR Grant NOOO 14-12-1-0226 Period of Performance: 01

  9. Acoustic Seaglider: Planning for the Philippine Sea

    National Research Council Canada - National Science Library

    Howe, Bruce M

    2008-01-01

    .... In all cases, the detailed understanding of acoustic propagation, ocean variability, temporal and spatial coherence ambient sound and the assimilation of data in models is essential for improved...

  10. Acoustic concentration of particles in fluid flow

    Science.gov (United States)

    Ward, Michael D.; Kaduchak, Gregory

    2010-11-23

    An apparatus for acoustic concentration of particles in a fluid flow includes a substantially acoustically transparent membrane and a vibration generator that define a fluid flow path therebetween. The fluid flow path is in fluid communication with a fluid source and a fluid outlet and the vibration generator is disposed adjacent the fluid flow path and is capable of producing an acoustic field in the fluid flow path. The acoustic field produces at least one pressure minima in the fluid flow path at a predetermined location within the fluid flow path and forces predetermined particles in the fluid flow path to the at least one pressure minima.

  11. Acoustic concentration of particles in fluid flow

    Science.gov (United States)

    Ward, Michael W.; Kaduchak, Gregory

    2017-08-15

    Disclosed herein is a acoustic concentration of particles in a fluid flow that includes a substantially acoustically transparent membrane and a vibration generator that define a fluid flow path therebetween. The fluid flow path is in fluid communication with a fluid source and a fluid outlet and the vibration generator is disposed adjacent the fluid flow path and is capable of producing an acoustic field in the fluid flow path. The acoustic field produces at least one pressure minima in the fluid flow path at a predetermined location within the fluid flow path and forces predetermined particles in the fluid flow path to the at least one pressure minima.

  12. Acoustic Particle Detection with the ANTARES Detector

    Directory of Open Access Journals (Sweden)

    M. Neff

    2010-01-01

    Full Text Available The (Antares Modules for Acoustic Detection Under the Sea AMADEUS system within the (Astronomy with a Neutrino Telescope and Abyss environmental RESsearch ANTARES neutrino telescope is designed to investigate detection techniques for acoustic signals produced by particle cascades. While passing through a liquid a cascade deposits energy and produces a measurable pressure pulse. This can be used for the detection of neutrinos with energies exceeding 1018 eV. The AMADEUS setup consists of 36 hydrophones grouped in six local clusters measuring about one cubic meter each. This article focuses on acoustic particle detection, the hardware of the AMADEUS detector and techniques used for acoustic signal processing.

  13. Acoustic Particle Detection with the ANTARES Detector

    Directory of Open Access Journals (Sweden)

    Richardt C

    2010-01-01

    Full Text Available The (Antares Modules for Acoustic Detection Under the Sea AMADEUS system within the (Astronomy with a Neutrino Telescope and Abyss environmental RESsearch ANTARES neutrino telescope is designed to investigate detection techniques for acoustic signals produced by particle cascades. While passing through a liquid a cascade deposits energy and produces a measurable pressure pulse. This can be used for the detection of neutrinos with energies exceeding  eV. The AMADEUS setup consists of 36 hydrophones grouped in six local clusters measuring about one cubic meter each. This article focuses on acoustic particle detection, the hardware of the AMADEUS detector and techniques used for acoustic signal processing.

  14. Acoustic resonance for nonmetallic mine detection

    Energy Technology Data Exchange (ETDEWEB)

    Kercel, S.W.

    1998-04-01

    The feasibility of acoustic resonance for detection of plastic mines was investigated by researchers at the Oak Ridge National Laboratory`s Instrumentation and Controls Division under an internally funded program. The data reported in this paper suggest that acoustic resonance is not a practical method for mine detection. Representative small plastic anti-personnel mines were tested, and were found to not exhibit detectable acoustic resonances. Also, non-metal objects known to have strong acoustic resonances were tested with a variety of excitation techniques, and no practical non-contact method of exciting a consistently detectable resonance in a buried object was discovered. Some of the experimental data developed in this work may be useful to other researchers seeking a method to detect buried plastic mines. A number of excitation methods and their pitfalls are discussed. Excitation methods that were investigated include swept acoustic, chopped acoustic, wavelet acoustic, and mechanical shaking. Under very contrived conditions, a weak response that could be attributed to acoustic resonance was observed, but it does not appear to be practical as a mine detection feature. Transfer properties of soil were investigated. Impulse responses of several representative plastic mines were investigated. Acoustic leakage coupling, and its implications as a disruptive mechanism were investigated.

  15. Acoustic Purcell Effect for Enhanced Emission

    KAUST Repository

    Landi, Maryam

    2018-03-13

    We observe that our experimentally measured emission power enhancement of a speaker inside a previously proposed metacavity agrees with our numerically calculated enhancement of the density of states (DOS) of the source-cavity system. We interpret the agreement by formulating a relation between the emitted sound power and the acoustic DOS. The formulation is an analog to Fermi’s golden rule in quantum emission. The formulation complements the radiation impedance theory in traditional acoustics for describing sound emission. Our study bridges the gap between acoustic DOS and the acoustic Purcell effect for sound emission enhancement.

  16. Relationships between acoustic emissions and microstructures

    International Nuclear Information System (INIS)

    Rao, G.V.; Gopal, R.

    1979-01-01

    Results of a systematic study of 'microstructure-deformation-acoustic emission' relationships on two widely used pressure retaining component materials, namely A533-B nuclear pressure vessel steel and a 7075 aluminum alloy, are presented. The study consists of conducting acoustic monitored tensile tests on a variety of quenched and aged microstructures in the two alloy systems and extensive microstructural characterization of test specimens by light optic and electron microscopy techniques. The results suggest a consistent relationship between acoustic emissions and microdeformation mechanisms. The role of specific microstructural constituents in generating acoustic emissions in the two alloys is discussed. (author)

  17. Acoustic concerns related to multi cultural societies

    DEFF Research Database (Denmark)

    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 Commission and carried out in cooperation among researchers in Turkey, Malta, Italy, France, Switzerland....... It is suggested that these soundscapes can provide comfort to recent immigrants by increasing their sense of being ``at home.''...

  18. Experimental verification of transient nonlinear acoustical holography.

    Science.gov (United States)

    Jing, Yun; Cannata, Jonathan; Wang, Tianren

    2013-05-01

    This paper presents an experimental study on nonlinear transient acoustical holography. The validity and effectiveness of a recently proposed nonlinear transient acoustical holography algorithm is evaluated in the presence of noise. The acoustic field measured on a post-focal plane of a high-intensity focused transducer is backward projected to reconstruct the pressure distributions on the focal and a pre-focal plane, which are shown to be in good agreement with the measurement. In contrast, the conventional linear holography produces erroneous results in this case where the nonlinearity involved is strong. Forward acoustic field projection was also carried out to further verify the algorithm.

  19. Supersonic acoustic intensity with statistically optimized near-field acoustic holography

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Jacobsen, Finn

    2011-01-01

    to the information provided by the near-field acoustic holography technique. This study proposes a version of the supersonic acoustic intensity applied to statistically optimized near-field acoustic holography (SONAH). The theory, numerical results and an experimental study are presented. The possibility of using...

  20. Near-Real-Time Acoustic Monitoring of Beaked Whales and Other Cetaceans Using a Seaglider(TM)

    Science.gov (United States)

    2012-05-18

    S, et al. (2008) Temporal patterns in the acoustic signals of beaked whales at Cross Seamount . Biology Letters 4: 208–211. 29. McDonald MA, Hildebrand...Satellite tracking reveals distinct movement patterns for Type B and Type C killer whales in the southern Ross Sea, Antarctica. Polar Biology 31: 1461...Volume 7 | Issue 5 | e36128 the 15th Biennial Conference on the Biology of Marine Mammals, Greensboro, North Carolina, USA. 10 p. 22. Aschettino JM