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Sample records for acoustic test setup

  1. Design and performance of the South Pole Acoustic Test Setup

    CERN Document Server

    Abdou, Yasser; Berdermann, Jens; Bissok, Martin; Bohm, Christian; Boeser, Sebastian; Bothe, Martin; Carson, Michael; Descamps, Freija; Fischer-Wolfarth, Jan-Hendrik; Gustafsson, Leif; Hallgren, Allan; Heinen, Dirk; Helbing, Klaus; Heller, Reinhart; Hundertmark, Stephan; Karg, Timo; Krieger, Kevin; Laihem, Karim; Meures, Thomas; Nahnhauer, Rolf; Naumann, Uwe; Oberson, Filip; Paul, Larissa; Pohl, Mario; Price, Buford; Ribordy, Mathieu; Ryckbosch, Dirk; Schunck, Matthias; Semburg, Benjamin; Stegmaier, Jutta; Sulanke, Karl-Heinz; Tosi, Delia; Vandenbroucke, Justin; Wiebusch, Christopher

    2011-01-01

    The South Pole Acoustic Test Setup (SPATS) was built to evaluate the acoustic characteristics of the South Pole ice in the 10 kHz to 100 kHz frequency range, for the purpose of assessing the feasibility of an acoustic neutrino detection array at the South Pole. The SPATS hardware consists of four vertical strings deployed in the upper 500 m of the South Pole ice cap. The strings form a trapezoidal array with a maximum baseline of 543 m. Each string has 7 stages equipped with one transmitter and one sensor module. Sound is detected or generated by piezoelectric ceramic elements inside the modules. Analogue signals are sent to the surface on electric cables where they are digitized by a PC-based data acquisition system. The data from all strings are collected on a central computer in the IceCube Laboratory from where they are send to a central data storage facility via a satellite link or stored locally on tape. A technical overview of SPATS and its performance is presented.

  2. Status and recent results of the South Pole Acoustic Test Setup

    CERN Document Server

    Karg, Timo

    2010-01-01

    The South Pole Acoustic Test Setup (SPATS) has been deployed to study the feasibility of acoustic neutrino detection in Antarctic ice around the South Pole. An array of four strings equipped with acoustic receivers and transmitters, permanently installed in the upper 500 m of boreholes drilled for the IceCube neutrino observatory, and a retrievable transmitter that can be used in the water filled holes before the installation of the IceCube optical strings are used to measure the ice acoustic properties. These include the sound speed and its depth dependence, the attenuation length, the noise level, and the rate and nature of transient background sources in the relevant frequency range from 10 kHz to 100 kHz. SPATS is operating successfully since January 2007 and has been able to either measure or constrain all parameters. We present the latest results of SPATS and discuss their implications for future acoustic neutrino detection activities in Antarctica.

  3. Feasibility of acoustic neutrino detection in ice: Design and performance of the South Pole Acoustic Test Setup (SPATS)

    CERN Document Server

    Boeser, S; Descamps, F; Fischer, J; Hallgren, A; Heller, R; Hundertmark, S; Krieger, K; Nahnhauer, R; Pohl, M; Price, P B; Sulanke, K -H; Tosi, D; Vandenbroucke, J

    2008-01-01

    The South Pole Acoustic Test Setup (SPATS) has been built to evaluate the acoustic characteristics of the South Pole ice in the 10 to 100 kHz frequency range so that the feasibility and specific design of an acoustic neutrino detection array at South Pole can be evaluated. SPATS consists of three vertical strings that were deployed in the upper 400 meters of the South Pole ice cap in January 2007, using the upper part of IceCube holes. The strings form a triangular array with the longest baseline 421 meters. Each of them has 7 stages with one transmitter and one sensor module. Both are equipped with piezoelectric ceramic elements in order to produce or detect sound. Analog signals are brought to the surface on electric cables where they are digitized by a PC-based data acquisition system. The data from all three strings are collected on a master-PC in a central facility, from which they are sent to the northern hemisphere via a satellite link or locally stored on tape. A technical overview of the SPATS detect...

  4. An In-vitro test set-up for evaluation of a voice-producing element under physiologic acoustic conditions

    NARCIS (Netherlands)

    Van der Plaats, A; Schutte, HK; Van der Eerden, FJM; De Vries, MP; Mahieu, HF; Verkerke, GJ

    2006-01-01

    To improve the voice quality of laryngectomised patients, a voice-producing element has been developed. Prior to in vivo testing we constructed and validated an in-vitro test set-up, consisting of a physical model of the subglottal tract and three physical models of the vocal tract, for the vowels /

  5. Non-contact test set-up for aeroelasticity in a rotating turbomachine combining a novel acoustic excitation system with tip-timing

    Science.gov (United States)

    Freund, O.; Montgomery, M.; Mittelbach, M.; Seume, J. R.

    2014-03-01

    Due to trends in aero-design, aeroelasticity becomes increasingly important in modern turbomachines. Design requirements of turbomachines lead to the development of high aspect ratio blades and blade integral disc designs (blisks), which are especially prone to complex modes of vibration. Therefore, experimental investigations yielding high quality data are required for improving the understanding of aeroelastic effects in turbomachines. One possibility to achieve high quality data is to excite and measure blade vibrations in turbomachines. The major requirement for blade excitation and blade vibration measurements is to minimize interference with the aeroelastic effects to be investigated. Thus in this paper, a non-contact—and thus low interference—experimental set-up for exciting and measuring blade vibrations is proposed and shown to work. A novel acoustic system excites rotor blade vibrations, which are measured with an optical tip-timing system. By performing measurements in an axial compressor, the potential of the acoustic excitation method for investigating aeroelastic effects is explored. The basic principle of this method is described and proven through the analysis of blade responses at different acoustic excitation frequencies and at different rotational speeds. To verify the accuracy of the tip-timing system, amplitudes measured by tip-timing are compared with strain gage measurements. They are found to agree well. Two approaches to vary the nodal diameter (ND) of the excited vibration mode by controlling the acoustic excitation are presented. By combining the different excitable acoustic modes with a phase-lag control, each ND of the investigated 30 blade rotor can be excited individually. This feature of the present acoustic excitation system is of great benefit to aeroelastic investigations and represents one of the main advantages over other excitation methods proposed in the past. In future studies, the acoustic excitation method will be used

  6. Acoustically Induced Vibration of Structures: Reverberant Vs. Direct Acoustic Testing

    Science.gov (United States)

    Kolaini, Ali R.; O'Connell, Michael R.; Tsoi, Wan B.

    2009-01-01

    Large reverberant chambers have been used for several decades in the aerospace industry to test larger structures such as solar arrays and reflectors to qualify and to detect faults in the design and fabrication of spacecraft and satellites. In the past decade some companies have begun using direct near field acoustic testing, employing speakers, for qualifying larger structures. A limited test data set obtained from recent acoustic tests of the same hardware exposed to both direct and reverberant acoustic field testing has indicated some differences in the resulting structural responses. In reverberant acoustic testing, higher vibration responses were observed at lower frequencies when compared with the direct acoustic testing. In the case of direct near field acoustic testing higher vibration responses appeared to occur at higher frequencies as well. In reverberant chamber testing and direct acoustic testing, standing acoustic modes of the reverberant chamber or the speakers and spacecraft parallel surfaces can strongly couple with the fundamental structural modes of the test hardware. In this paper data from recent acoustic testing of flight hardware, that yielded evidence of acoustic standing wave coupling with structural responses, are discussed in some detail. Convincing evidence of the acoustic standing wave/structural coupling phenomenon will be discussed, citing observations from acoustic testing of a simple aluminum plate. The implications of such acoustic coupling to testing of sensitive flight hardware will be discussed. The results discussed in this paper reveal issues with over or under testing of flight hardware that could pose unanticipated structural and flight qualification issues. Therefore, it is of paramount importance to understand the structural modal coupling with standing acoustic waves that has been observed in both methods of acoustic testing. This study will assist the community to choose an appropriate testing method and test setup in

  7. Optical test setup for Silicon Photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Heidemann, Carsten; Enzweiler, Tim; Hebbeker, Thomas; Merschmeyer, Markus

    2015-07-01

    Silicon Photomultipliers (SiPMs) are semiconductor-based photon detectors. Their most important properties, gain and photon detection efficiency, are dependent on or influenced by voltage and temperature and need to be characterised for optimal usage of the SiPMs. The test setup has been built for optical and electrical characterisation of SiPMs. The setup provides a temperature-stabilised SiPM mount, an LED-based multi-purpose light source offers continuous and pulsed operation mode for wavelengths from 300 nm to 650 nm. The result is a complete characterisation of the SiPM within a desired range of operation voltage and ambient temperature.

  8. Advanced Laboratory Setup for Testing Offshore Foundations

    DEFF Research Database (Denmark)

    Nielsen, Søren Dam; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl

    2016-01-01

    This paper describes a test setup for testing small-scale offshore foundations under realistic conditions of high pore-water pressure and high impact loads. The actuator, used for loading has enough capacity to apply sufficient force and displacement to achieve both drained and undrained failure...... modes for small-scale offshore foundations. Results from trial tests on two small-scale bucket foundations, subjected to transient or cyclic loading, are presented. Tests showed that cavitation limits the undrained bearing capacity. Hence, a high pore-water pressure is important for simulating offshore...

  9. 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...

  10. 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.

  11. Test Setup for Axially Loaded Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    The test setup for testing axially static and cyclic loaded piles in sand is described in the following. The purpose for the tests is to examine the tensile capacity of axially loaded piles in dense fully saturated sand. The pile dimensions are chosen to resemble full scale dimension of piles used...... in offshore pile foundations today....

  12. Experimental Setup for Validation Tests in Arc-Heated Facilities

    OpenAIRE

    Esser, Burkard

    2015-01-01

    This document describes the experimental setup for the thermal verification tests in the frame of the EU FP7 Project THOR. It includes a description of the preparatory work in WP6, in particular the assembly of the test models as well as a detailed description of instrumentation and measurement techniques.

  13. New ESD Test Set-Up for Spacecraft Equipment

    Science.gov (United States)

    Daout, B.; Romero, C.; Pelissou, P.; Wolf, K.-F. J.

    2016-05-01

    The ESD test method according to ECSS-E-ST-20-07C [1] has shown weaknesses in reproducibility and reliability. We have previously shown that test results can vary from one test laboratory and setup to another [2], this entails developing an improved methodology and hardware to address the ECSS test shortcomings. In this paper, a new topology and a generator built using a pressurized high voltage relay, a compensation circuit and a bulk current injection (BCI) probe as a coupling device instead of the 20 cm wire described in the current ECSS standard are presented. The generator and the suggested test set-up have been evaluated in different configurations showing an improved reproducibility and a simpler testing procedure.

  14. 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...

  15. Cryogenic Acoustic Suppression Testing Project

    Data.gov (United States)

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

  16. Quick setup of unit test for accelerator controls system

    Energy Technology Data Exchange (ETDEWEB)

    Fu, W.; D' Ottavio, T.; Gassner, D.; Nemesure, S.; Morris, J.

    2011-03-28

    Testing a single hardware unit of an accelerator control system often requires the setup of a program with graphical user interface. Developing a dedicated application for a specific hardware unit test could be time consuming and the application may become obsolete after the unit tests. This paper documents a methodology for quick design and setup of an interface focused on performing unit tests of accelerator equipment with minimum programming work. The method has three components. The first is a generic accelerator device object (ADO) manager which can be used to setup, store, and log testing controls parameters for any unit testing system. The second involves the design of a TAPE (Tool for Automated Procedure Execution) sequence file that specifies and implements all te testing and control logic. The sting third is the design of a PET (parameter editing tool) page that provides the unit tester with all the necessary control parameters required for testing. This approach has been used for testing the horizontal plane of the Stochastic Cooling Motion Control System at RHIC.

  17. Acoustic Climb to Cruise Test

    Science.gov (United States)

    1991-01-01

    Flight test film footage of three different aircraft testing the acoustical noise levels during take-off, climb, maneuvers, and touch and go landings are described. These sound tests were conducted on two fighter aircraft and one cargo aircraft. Results from mobile test vehicle are shown.

  18. Cryogenic actuator testing for the SAFARI ground calibration setup

    Science.gov (United States)

    de Jonge, C.; Eggens, M.; Nieuwenhuizen, A. C. T.; Detrain, A.; Smit, H.; Dieleman, P.

    2012-09-01

    For the on-ground calibration setup of the SAFARI instrument cryogenic mechanisms are being developed at SRON Netherlands Institute for Space Research, including a filter wheel, XYZ-scanner and a flipmirror mechanism. Due to the extremely low background radiation requirement of the SAFARI instrument, all of these mechanisms will have to perform their work at 4.5 Kelvin and low-dissipative cryogenic actuators are required to drive these mechanisms. In this paper, the performance of stepper motors, piezoelectric actuators and brushless DC-motors as cryogenic actuators are compared. We tested stepper motor mechanical performance and electrical dissipation at 4K. The actuator requirements, test setup and test results are presented. Furthermore, design considerations and early performance tests of the flipmirror mechanism are discussed. This flipmirror features a 102 x 72 mm aluminum mirror that can be rotated 45°. A Phytron stepper motor with reduction gearbox has been chosen to drive the flipmirror. Testing showed that this motor has a dissipation of 49mW at 4K with a torque of 60Nmm at 100rpm. Thermal modeling of the flipmirror mechanism predicts that with proper thermal strapping the peak temperature of the flipmirror after a single action will be within the background level requirements of the SAFARI instrument. Early tests confirm this result. For low-duty cycle operations commercial stepper motors appear suitable as actuators for test equipment in the SAFARI on ground calibration setup.

  19. Universal system for the automation of test setups

    Science.gov (United States)

    Buturuga, Alexandru; Constantinescu, Rodica; Stoichescu, Dan

    2016-12-01

    This paper presents the concept of a universal control system for automation of small test setups. The main purpose is to control the environment in which the electronic component is being tested. The system has two device types: a master device and multiple slave devices. In this control system the devices are able to communicate with each other and are able to monitor and control specific tasks or actions required in the test flow. The system can be configured using a computer application based on text input.

  20. Magnet Test Setup of the CMS Tracker ready for installation

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The pieces of the Tracker that will be operated in the forthcoming Magnet Test and Cosmic Challenge (MTCC) have been transported inside the dummy tracker support tube to the CMS experimental hall (Point 5, Cessy). The operation took place during the night of 12th May, covering the ~15km distance in about three hours. The transport was monitored for shocks, temperature and humidity with the help of the CERN TS-IC section. The Tracker setup comprises segments of the Tracker Inner Barrel (TIB), the Tracker Outer Barrel (TOB) and Tracker EndCaps (TEC) detectors. It represents roughly 1% of the final CMS Tracker. Installation into the solenoid is foreseen to take place on Wednesday 17th May.

  1. HVI-Test Setup for Debris Detector Verification

    Science.gov (United States)

    Bauer, Waldemar; Romberg, Oliver; Wiedemann, Carsten; Putzar, Robin; Drolshagen, Gerhard; Vorsmann, Peter

    2013-08-01

    concerning space debris and micrometeoroids. In this way, the SOLID method will allow the generation of a large amount of impact data for environmental model validation. The ground verification of the SOLID method was performed at Fraunhofer EMI. For this purpose, a test model was developed. This paper focuses on the test methodology and development of the Hypervelocity Impact (HVI) test setup, including pretesting at the German Aerospace Centre (DLR), Bremen. Foreseen hardware and software for the automatic damage assessment of the detector after the impact are also presented.

  2. Payload bay atmospheric vent airflow testing at the Vibration and Acoustic Test Facility

    Science.gov (United States)

    Johnston, James D., Jr.

    1988-01-01

    Several concerns related to venting the Space Shuttle Orbiter payload bay during launch led to laboratory experiments with a flight-type vent box installed in the wall of a subsonic wind tunnel. This report describes the test setups and procedures used to acquire data for characterization of airflow through the vent box and acoustic tones radiated from the vent-box cavity. A flexible boundary-layer spoiler which reduced the vent-tone amplitude is described.

  3. Gas diffusion electrode setup for catalyst testing in concentrated phosphoric acid at elevated temperatures

    DEFF Research Database (Denmark)

    Wiberg, Gustav Karl Henrik; Fleige, Michael; Arenz, Matthias

    2015-01-01

    field are braced using a KF-25 vacuum flange clamp, which allows an easy assembly of the setup. As demonstrated, the setup can be used to investigate temperature dependent electrochemical processes on high surface area type electrocatalysts, but it also enables quick screening tests of HT...

  4. Force Measurements in Vibration and Acoustic Tests

    Science.gov (United States)

    Scharton, T. D.

    1996-01-01

    The advent of triaxial, piezoelectric force gages and the associated signal processing is a precursor to several dynamics testing innovations. This new technology is applicable to spacecraft programs that JPL manages. An application of force measurement is force limiting (when testing spacecraft in random vibration tests). Base-drive and acoustic modal testing is a potential application.

  5. Airflow Test of Acoustic Board Samples

    DEFF Research Database (Denmark)

    Jensen, Rasmus Lund; Jensen, Lise Mellergaard

    In the laboratory of Indoor Environmental Engineering, Department of Civil Engineering, Aalborg University an airflow test on 2x10 samples of acoustic board were carried out the 2nd of June 2012. The tests were carried out for Rambøll and STO AG. The test includes connected values of volume flow...

  6. Evaluation of Reflections in a MIMO OTA Test Setup

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del; Franek, Ondrej; Krenz, Gunter

    2014-01-01

    With the commercialization of MIMO devices, accurate over-the-air testing has become a major research area in mobile communications. Several test methods are investigated in the related work. This paper discusses the anechoic chamber method and specifically deals with reflections between probes...

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

    Science.gov (United States)

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

    2014-01-01

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

  8. Setup of IN VIVO Breast Cancer Models for Nanodrug Testing

    DEFF Research Database (Denmark)

    Schifter, Søren

    for detection of the primary tumor and metastasis and the efficacy of siRNA delivery is measured by reporter gene-targeting siRNAs and in vivo imaging. The use of a uniform siRNA not affecting cellular processes would allow for standardized assessment of siRNA delivery to cancer cells without interferences via......RNA/aptamer conjugates, or carriers such as liposome/chitosan/micelle spheres. As a first step towards testing of the efficacy of siRNA delivery in vivo via different conjugates and complexes, we aimed at developing a standardized breast cancer model system in mice. In this conception, a reporter gene is used...... differential knockdown efficacies and the readout can directly be performed by quantitative imaging using a Caliper IVIS system. In one line of experiments, we engineered non-metastatic MCF-7 breast cancer cells to express the luminescent reporter firefly luciferase (Luc2) along with a pro-metastatic micro...

  9. Advanced Test Method of Solid Oxide Cells in a Plug-Flow Setup

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard; Hauch, Anne; Hendriksen, Peter Vang;

    2009-01-01

    This paper describes a case study of two electrolysis tests of solid oxide cells [Ni/yttria-stabilized zirconia (YSZ)-YSZ-lanthanum strontium manganite (LSM)/YSZ] tested in a plug-flow setup. An extensively instrumented cell test setup was used, and the tests involved measurements of the cell...... electrolysis conditions. From measurements of the in-plane voltages in the electrodes and impedance spectra obtained during the electrolysis operation, we derive information about the resistance distributions in the Ni electrodes and describe how these distributions evolve over time. Impedance spectra at open...

  10. MIMO OTA Testing in Small Multi-Probe Anechoic Chamber Setups

    DEFF Research Database (Denmark)

    Llorente, Ines Carton; Fan, Wei; Pedersen, Gert F.

    2016-01-01

    OTA testing of MIMO capable terminals is often performed in large anechoic chambers, where planar waves impinging the test area are assumed. Furthermore, reflections from the chamber, and probe coupling are often considered negligible due to the large dimensions of the chamber. This paper...... investigates the feasibility of reducing the physical dimension of 2D multi-probe anechoic chamber setups for MIMO OTA testing, with the purpose of reducing the cost and space of the setup. In the paper, a channel emulation algorithm and chamber compensation technique are proposed for MIMO OTA testing in small...

  11. Setup, tests and results for the ATLAS TileCal Read Out Driver production

    CERN Document Server

    Valero, Alberto; Castillo, V; Cuenca, C; Ferrer, A; Fullana, E; González, V; Higón, E; Munar, A; Poveda, J; Ruiz-Martínez, A; Salvachúa, B; Sanchís, E; Solans, C; Soret, J; Torres, J; Valls, J A

    2007-01-01

    In this paper we describe the performance and test results of the production of the 38 ATLAS TileCal Read Out Drivers (RODs). We first describe the basic hardware specifications and firmware functionality of the modules, the test-bench setup used for production and the test procedure to qualify the boards. We then finally show and discuss the performance results.

  12. Impact of Acoustic Standing Waves on Structural Responses: Reverberant Acoustic Testing (RAT) vs. Direct Field Acoustic Testing (DFAT)

    Science.gov (United States)

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

    2012-01-01

    Loudspeakers have been used for acoustic qualification of spacecraft, reflectors, solar panels, and other acoustically responsive structures for more than a decade. Limited measurements from some of the recent speaker tests used to qualify flight hardware have indicated significant spatial variation of the acoustic field within the test volume. Also structural responses have been reported to differ when similar tests were performed using reverberant chambers. To address the impact of non-uniform acoustic field on structural responses, a series of acoustic tests were performed using a flat panel and a 3-ft cylinder exposed to the field controlled by speakers and repeated in a reverberant chamber. The speaker testing was performed using multi-input-single-output (MISO) and multi-input-multi-output (MIMO) control schemes with and without the test articles. In this paper the spatial variation of the acoustic field due to acoustic standing waves and their impacts on the structural responses in RAT and DFAT (both using MISO and MIMO controls for DFAT) are discussed in some detail.

  13. Tuned Chamber Core Panel Acoustic Test Results

    Science.gov (United States)

    Schiller, Noah H.; Allen, Albert R.

    2016-01-01

    This report documents acoustic testing of tuned chamber core panels, which can be used to supplement the low-frequency performance of conventional acoustic treatment. The tuned chamber core concept incorporates low-frequency noise control directly within the primary structure and is applicable to sandwich constructions with a directional core, including corrugated-, truss-, and fluted-core designs. These types of sandwich structures have long, hollow channels (or chambers) in the core. By adding small holes through one of the facesheets, the hollow chambers can be utilized as an array of low-frequency acoustic resonators. These resonators can then be used to attenuate low-frequency noise (below 400 Hz) inside a vehicle compartment without increasing the weight or size of the structure. The results of this test program demonstrate that the tuned chamber core concept is effective when used in isolation or combined with acoustic foam treatments. Specifically, an array of acoustic resonators integrated within the core of the panels was shown to improve both the low-frequency absorption and transmission loss of the structure in targeted one-third octave bands.

  14. Test of the ALICE DDL Test setups and Test of ALICE DDL Integration to ALICE TPC test system

    CERN Document Server

    Csató, P; Sulyán, J; Rubin, G; Tarján, D; Vissy, B

    1998-01-01

    Presentation made at the 4th Workshop on Electronics for LHC Experiments, INFN Rome, 21-25 September 1998.The Detector Data Link (DDL) has been developed to constitute a standard interface between the ALICE sub-detectors and the DAQ system.In this paper we present the test environment and the application software library made for supporting the DDL development and its integration into the ALICE detector system. The test setups contain VME64 crates, MVME processor cards, a VMETRO analyser, a logic-analyser and Read-out-Receiver (RORC) andDestination-Interface-Unit (DIU) cards. They made possible to measure the maximum throughput of the full read-out chain and also to measurethe transmission latencies. They support the functional and long-term stability tests as well.

  15. Validation and Simulation of ARES I Scale Model Acoustic Test -1- Pathfinder Development

    Science.gov (United States)

    Putnam, G. C.

    2011-01-01

    The Ares I Scale Model Acoustics Test (ASMAT) is a series of live-fire tests of scaled rocket motors meant to simulate the conditions of the Ares I launch configuration. These tests have provided a well documented set of high fidelity measurements useful for validation including data taken over a range of test conditions and containing phenomena like Ignition Over-Pressure and water suppression of acoustics. To take advantage of this data, a digital representation of the ASMAT test setup has been constructed and test firings of the motor have been simulated using the Loci/CHEM computational fluid dynamics software. Within this first of a series of papers, results from ASMAT simulations with the rocket in a held down configuration and without water suppression have then been compared to acoustic data collected from similar live-fire tests to assess the accuracy of the simulations. Detailed evaluations of the mesh features, mesh length scales relative to acoustic signals, Courant-Friedrichs-Lewy numbers, and spatial residual sources have been performed to support this assessment. Results of acoustic comparisons have shown good correlation with the amplitude and temporal shape of pressure features and reasonable spectral accuracy up to approximately 1000 Hz. Major plume and acoustic features have been well captured including the plume shock structure, the igniter pulse transient, and the ignition overpressure. Finally, acoustic propagation patterns illustrated a previously unconsidered issue of tower placement inline with the high intensity overpressure propagation path.

  16. Vibration and acoustic testing of spacecraft

    Science.gov (United States)

    Scharton, T. D.

    2002-01-01

    Spacecraft are subjected to a variety of dynamics environments, which may include: quasi-static, vibration and acoustic loads at launch: pyrotechnic shocks generated by separation mechanisms; on orbit jitter; and sometimes, planetary landing loads. There is a trend in the aerospace industry to rely more on structural analyses and less on testing to simulate these environments, because dynamics testing of spacecraft is time consuming, risky and expensive.

  17. Vibration and Acoustic Testing for Mars Micromission Spacecraft

    Science.gov (United States)

    Kern, Dennis L.; Scharton, Terry D.

    1999-01-01

    spacecraft and the test fixture, alleviates the severe overtest at spacecraft resonances inherent in rigid fixture vibration tests. It has the distinct advantage over response limiting that the method is not dependent on the accuracy of a detailed dynamic model of the spacecraft. Combined loads, vibration, and modal testing were recently performed on the QuikSCAT spacecraft. The combined tests were performed in a single test setup per axis on a vibration shaker, reducing test time by a factor of two or three. Force gages were employed to measure the true c.g. acceleration of the spacecraft for structural loads verification using a sine burst test, to automatically notch random vibration test input accelerations at spacecraft resonances based on predetermined force limits, and to directly measure modal masses in a base drive modal test. In addition to these combined tests on the shaker, the QuikSCAT spacecraft was subjected to a direct field acoustic test by surrounding the spacecraft, still on the vibration shaker, with rock concert type acoustic speakers. Since the spacecraft contractor does not have a reverberant field acoustic test facility, performing a direct field acoustic test -saved the program nearly two weeks schedule time that would have been required for packing / unpacking and shipping of the spacecraft. This paper discusses the rationale behind and advantages of the above test approaches and provides examples of their actual implementation and comparisons to flight data. The applicability of the test approaches to Mars Micromission spacecraft qualification is discussed.

  18. Acoustic emission non-destructive testing of structures using source location techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, Alan G.

    2013-09-01

    The technology of acoustic emission (AE) testing has been advanced and used at Sandia for the past 40 years. AE has been used on structures including pressure vessels, fire bottles, wind turbines, gas wells, nuclear weapons, and solar collectors. This monograph begins with background topics in acoustics and instrumentation and then focuses on current acoustic emission technology. It covers the overall design and system setups for a test, with a wind turbine blade as the object. Test analysis is discussed with an emphasis on source location. Three test examples are presented, two on experimental wind turbine blades and one on aircraft fire extinguisher bottles. Finally, the code for a FORTRAN source location program is given as an example of a working analysis program. Throughout the document, the stress is on actual testing of real structures, not on laboratory experiments.

  19. On Dimensions of OTA Setups for Massive MIMO Base Stations Radiated Testing

    DEFF Research Database (Denmark)

    Kyösti, Pekka; Fan, Wei; Pedersen, Gert F.;

    2016-01-01

    (DoA) estimation algorithm as well as multi-user MIMO sum-rate capacity are investigated to determine the range of the test setup. It was found that the link budget doesn’t support for the measurement distances claimed by the Fraunhofer distance. Most of the utilized metrics, especially the sum rate...

  20. Design of Testing Set-up for Nuclear Fuel Rod by Neutron Radiography at CARR

    Institute of Scientific and Technical Information of China (English)

    WEI; Guo-hai; HAN; Song-bai; WANG; Hong-li; HAO; Li-jie; WU; Mei-mei; HE; Lin-feng; WANG; Yu; LIU; Yun-tao; SUN; Kai; CHEN; Dong-feng

    2012-01-01

    <正>An experimental set-up dedicated to non-destructively test a 15 cm long pressurized water reactor (PWR) nuclear fuel rod by neutron radiography (NR) is designed and fabricated. It consists of three parts: Transport container, imaging block and steel support. The design of the transport container was optimized with Monte-Carlo simulation by the MCNP code.

  1. Emulating Ray-Tracing Channels in Multi-probe Anechoic Chamber Setups for Virtual Drive Testing

    DEFF Research Database (Denmark)

    Fan, Wei; Llorente, Ines Carton; Kyösti, Pekka

    2016-01-01

    This paper discusses virtual drive testing (VDT) for multiple-input multiple-output (MIMO) capable terminals in multi-probe anechoic chamber (MPAC) setups. We propose to perform VDT, via reproducing ray tracing (RT) simulated channels with the field synthesis technique. Simulation results demonst...

  2. Design and building of a new experimental setup for testing hydrogen storage materials

    Energy Technology Data Exchange (ETDEWEB)

    Andreasen, Anders

    2005-09-01

    For hydrogen to become the future energy carrier a suitable way of storing hydrogen is needed, especially if hydrogen is to be used in mobile applications such as cars. To test potential hydrogen storage materials with respect to capacity, kinetics and thermodynamics the Materials Research Department has a high pressure balance. However, the drawback of this equipment is, that in order to load samples, exposure towards air is inevitable. This has prompted the design and building of a new experimental setup with a detachable reactor allowing samples to be loaded under protective atmosphere. The purpose of this report is to serve as documentation of the new setup. (au)

  3. Development of a grinding-specific performance test set-up

    DEFF Research Database (Denmark)

    Olesen, C. G.; Larsen, B. H.; Andresen, E. L.

    2015-01-01

    and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding......The aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding...... demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding...

  4. Development and Test of a Neutron Imaging Setup at the PGAA Instrument at FRM II

    Science.gov (United States)

    Söllradl, S.; Mühlbauer, M. J.; Kudejova, P.; Türler, A.

    We report on the developments of a neutron tomography setup at the instrument for prompt gamma-ray activation analysis (PGAA) at the Maier-Leibnitz Zentrum(MLZ). The recent developments are driven by the idea of combining the spatial information obtained with neutron tomography with the elemental information determined with PGAA, i.e. to further combine both techniques to an investigative technique called prompt gamma activation imaging (PGAI).At the PGAA instrument, a cold neutron flux of up to 6 x 1010 cm-2 s-1 (thermal equivalent) is available in the focus of an elliptically tapered neutron guide. In the reported experiments, the divergence of the neutron beam was investigated, the resolution of the installed detector system tested, and a proof-of-principle tomography experiment performed. In our study a formerly used camera box was upgraded with a better camera and an optical resolution of 8 line pairs/mm was achieved. The divergence of the neutron beam was measured by a systematic scan along the beam axis. Based on the acquired data, a neutron imaging setup with a L/D ratio of 200 was installed. The resolution of the setup was testedin combination with a gadolinium test target and different scintillator screens. The test target was irradiated at two positions to determine the maximum resolution and the resolution at the actual sample position. The performance of the installed tomography setup was demonstrated bya tomography experiment of an electric amplifier tube.

  5. TEST BEAM COORDINATION: The 2004 Test Beam Calorimetry set-up in H8

    CERN Multimedia

    Aleksa, M; Di Girolamo, B; Ferrari, C; Giugni, D; Santoni, C; Wingerter, I

    A new table has been designed, built and finally mounted to position the LAr cryostat in front of the Tilecal modules. The new table has been connected to the existing Tilecal table to be able to move the full set-up along eta values between 0 and 1.2. The table has been conceived by D. Giugni (INFN Milano and now CERN PH) and modeled by G. Braga (INFN Milano) in spring-summer 2003. The realization of the table has been done by an Italian firm (MatecImpianti, Fenegrò, Como) under the supervision of S. Coelli (INFN Milano) starting August 2003. Figure 1 shows the table assembled at the firm (left). Figure 1: The Tilecal-LAr table: in Fenegro (left) and at CERN (right). In November 2003 the table has been delivered to CERN and put in temporary storage to be assembled after the preparation of the Tilecal zone. In February 2004 two technicians from the firm and the team of technician coordinated by C. Ferrari (CERN AB/ATB), assembled, tested and commissioned the table under the supervision of S. Coelli...

  6. On Dimensions of OTA Setups for Massive MIMO Base Stations Radiated Testing

    DEFF Research Database (Denmark)

    Kyösti, Pekka; Fan, Wei; Pedersen, Gert F.;

    2016-01-01

    The development of base stations (BS) with large aperture antenna arrays, enabled partially by the utilization of cmWave and mmWave frequency bands, will require radiated testing in fading conditions. In this paper, the objective is to investigate the suitable measurement distances and physical...... (DoA) estimation algorithm as well as multi-user MIMO sum-rate capacity are investigated to determine the range of the test setup. It was found that the link budget doesn’t support for the measurement distances claimed by the Fraunhofer distance. Most of the utilized metrics, especially the sum rate...... capacity, indicate that smaller setup sizes can still yield reasonable measurement accuracy. Simulations were performed at 2.6, 3.5, and 28 GHz frequencies....

  7. The Development of the Acoustic Design of NASA Glenn Research Center's New Reverberant Acoustic Test Facility

    Science.gov (United States)

    Hughes, William O.; McNelis, Mark E.; Hozman, Aron D.; McNelis, Anne M.

    2011-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is leading the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC s Plum Brook Station in Sandusky, Ohio. Benham Companies, LLC is currently constructing modal, base-shake sine and reverberant acoustic test facilities to support the future testing needs of NASA s space exploration program. The large Reverberant Acoustic Test Facility (RATF) will be approximately 101,000 ft3 in volume and capable of achieving an empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world s known active reverberant acoustic test facilities. The key to achieving the expected acoustic test spectra for a range of many NASA space flight environments in the RATF is the knowledge gained from a series of ground acoustic tests. Data was obtained from several NASA-sponsored test programs, including testing performed at the National Research Council of Canada s acoustic test facility in Ottawa, Ontario, Canada, and at the Redstone Technical Test Center acoustic test facility in Huntsville, Alabama. The majority of these tests were performed to characterize the acoustic performance of the modulators (noise generators) and representative horns that would be required to meet the desired spectra, as well as to evaluate possible supplemental gas jet noise sources. The knowledge obtained in each of these test programs enabled the design of the RATF sound generation system to confidently advance to its final acoustic design and subsequent on-going construction.

  8. PV inverter test setup for European efficiency, static and dynamic MPPT efficiency evaluation

    DEFF Research Database (Denmark)

    Sera, Dezso; Teodorescu, Remus; Valentini, Massimo;

    2008-01-01

    This paper concerns the evaluation of performance of grid-connected PV inverters in terms of conversion efficiency, European efficiency, static and dynamic MPP efficiency. Semi-automated tests were performed in the PV laboratory of the Institute of Energy Technology at the Aalborg University...... (Denmark) on a commercial transformerless PV inverter. Thanks to the available experimental test setups, that provide the required high measuring accuracy, and the developed PV simulator, which is required for MPPT performance evaluation, PV Inverters can be pretested before being tested by accredited...

  9. Acoustic Test Results of Melamine Foam with Application to Payload Fairing Acoustic Attenuation Systems

    Science.gov (United States)

    Hughes, William O.; McNelis, Anne M.

    2014-01-01

    A spacecraft at launch is subjected to a harsh acoustic and vibration environment resulting from the passage of acoustic energy, created during the liftoff of a launch vehicle, through the vehicle's payload fairing. In order to ensure the mission success of the spacecraft it is often necessary to reduce the resulting internal acoustic sound pressure levels through the usage of acoustic attenuation systems. Melamine foam, lining the interior walls of the payload fairing, is often utilized as the main component of such a system. In order to better understand the acoustic properties of melamine foam, with the goal of developing improved acoustic attenuation systems, NASA has recently performed panel level testing on numerous configurations of melamine foam acoustic treatments at the Riverbank Acoustical Laboratory. Parameters assessed included the foam's thickness and density, as well as the effects of a top outer cover sheet material and mass barriers embedded within the foam. This testing followed the ASTM C423 standard for absorption and the ASTM E90 standard for transmission loss. The acoustic test data obtained and subsequent conclusions are the subjects of this paper.

  10. X-ray phase scanning setup for non-destructive testing using Talbot-Lau interferometer

    Science.gov (United States)

    Bachche, S.; Nonoguchi, M.; Kato, K.; Kageyama, M.; Koike, T.; Kuribayashi, M.; Momose, A.

    2016-09-01

    X-ray grating interferometry has a great potential for X-ray phase imaging over conventional X-ray absorption imaging which does not provide significant contrast for weakly absorbing objects and soft biological tissues. X-ray Talbot and Talbot-Lau interferometers which are composed of transmission gratings and measure the differential X-ray phase shifts have gained popularity because they operate with polychromatic beams. In X-ray radiography, especially for nondestructive testing in industrial applications, the feasibility of continuous sample scanning is not yet completely revealed. A scanning setup is frequently advantageous when compared to a direct 2D static image acquisition in terms of field of view, exposure time, illuminating radiation, etc. This paper demonstrates an efficient scanning setup for grating-based Xray phase imaging using laboratory-based X-ray source. An apparatus consisting of an X-ray source that emits X-rays vertically, optical gratings and a photon-counting detector was used with which continuously moving objects across the field of view as that of conveyor belt system can be imaged. The imaging performance of phase scanner was tested by scanning a long continuous moving sample at a speed of 5 mm/s and absorption, differential-phase and visibility images were generated by processing non-uniform moire movie with our specially designed phase measurement algorithm. A brief discussion on the feasibility of phase scanner with scanning setup approach including X-ray phase imaging performance is reported. The successful results suggest a breakthrough for scanning objects those are moving continuously on conveyor belt system non-destructively using the scheme of X-ray phase imaging.

  11. Servo drive chain evaluation test set-up and configuration methodology

    Directory of Open Access Journals (Sweden)

    R. Heera Singh

    2016-06-01

    Full Text Available The evaluation test bench set-up for servo drive chain consists of various servo sub-modules viz., generic motion controller, servo drive amplifier, brushless AC servo motor, torque coupler, gear reducer and shaft encoder assembly for position feedback is considered. The module interfaces are established for efficient use in commissioning, diagnosing and qualifying the antenna tracking chain. Design methodology demonstrated and specifications of systems were derived. Design specifications of drive chain are configured through software tools for optimizing rate loop and position loop. The transient behaviour and response of servo system using Proportional Integral Derivative controller in time as well in frequency domain is analyzed. Stability conditions are simulated and verified. The test set up energised and test results of different inputs verified and following error minimised by tuning/ optimising the system.

  12. Test Setup for Anechoic Room based MIMO OTA Testing of LTE Terminals

    DEFF Research Database (Denmark)

    Carreño, Xavier; Fan, Wei; Nielsen, Jesper Ødum;

    2013-01-01

    introduced into, for example, LTE andWiMAX systems. The main purpose of this testing is to validate that the user equipment will have a good performance in real use. CTIA, 3GPP and COST are spending a big effort in standardizing the OTA testing procedure which is much more complex than similar SISO OTA...

  13. Acoustical Analysis of a Test Horn.

    Science.gov (United States)

    1988-01-20

    Laboratories, Inc. if /pliable) Flight Dynamics Laboratory (AFWAL/ FIBRA ) n/a Air Force Wright Aeronautical Laboratories 6c. ADDRESS (City, State, and ZIPCode) 7b...AFWAL/ FIBRA DO Form 1473, JUN 86 Previous editions are obsolete. SECURITY CLASSIFICATION OF THIS PAGE UNCLASSIFIED "S.,, PREFACE This acoustical

  14. The influence of the test setup on knee joint kinematics - A meta-analysis of tibial rotation.

    Science.gov (United States)

    Hacker, Steffen P; Ignatius, Anita; Dürselen, Lutz

    2016-09-06

    The human knee is one of the most investigated joints in the human body. Various test setups exist to measure and analyse knee kinematics in vitro which differ in a wide range of parameters. The purpose of this article is to find an answer to the question if the test setup influences the kinematic outcome of studies and to what extend the results can be compared. To answer this question, we compared the tibial rotation as a function of flexion angle presented in 19 published studies. Raw data was extracted via image segmentation from the graphs depicted in these publications and the differences between the publications was analysed. Additionally, all test setups were compared regarding four aspects: method for angle calculation, system for data acquisition, loading condition and testing rig design. The resulting correlation matrix shows the influence of the test setup on the study outcome. Our results indicate that each study needs to collect its own reference data. Finally, we provide a mean internal rotation as a function of flexion angle based on more than 140 specimens tested in 14 different studies.

  15. The Testing Behind The Test Facility: The Acoustic Design of the NASA Glenn Research Center's World-Class Reverberant Acoustic Test Facility

    Science.gov (United States)

    Hozman, Aron D.; Hughes, William O.; McNelis, Mark E.; McNelis, Anne M.

    2011-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is leading the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC's Plum Brook Station in Sandusky, Ohio, USA. Benham Companies, LLC is currently constructing modal, base-shake sine and reverberant acoustic test facilities to support the future testing needs of NASA's space exploration program. The large Reverberant Acoustic Test Facility (RATF) will be approximately 101,000 cu ft in volume and capable of achieving an empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world's known active reverberant acoustic test facilities. The key to achieving the expected acoustic test spectra for a range of many NASA space flight environments in the RATF is the knowledge gained from a series of ground acoustic tests. Data was obtained from several NASA-sponsored test programs, including testing performed at the National Research Council of Canada's acoustic test facility in Ottawa, Ontario, Canada, and at the Redstone Technical Test Center acoustic test facility in Huntsville, Alabama, USA. The majority of these tests were performed to characterize the acoustic performance of the modulators (noise generators) and representative horns that would be required to meet the desired spectra, as well as to evaluate possible supplemental gas jet noise sources. The knowledge obtained in each of these test programs enabled the design of the RATF sound generation system to confidently advance to its final acoustic design and subsequent on-going construction.

  16. Sandia National Laboratories' new high level acoustic test facility

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J. D.; Hendrick, D. M.

    1989-01-01

    A high intensity acoustic test facility has been designed and is under construction at Sandia National Laboratories in Albuquerque, NM. The chamber is designed to provide an acoustic environment of 154dB (re 20 {mu}Pa) overall sound pressure level over the bandwidth of 50 Hz to 10,000 Hz. The chamber has a volume of 16,000 cubic feet with interior dimensions of 21.6 ft {times} 24.6 ft {times} 30 ft. The construction of the chamber should be complete by the summer of 1990. This paper discusses the design goals and constraints of the facility. The construction characteristics are discussed in detail, as are the acoustic performance design characteristics. The authors hope that this work will help others in designing acoustic chambers. 12 refs., 6 figs.

  17. The experimental setup of a large field operational test for cooperative driving vehicles at the A270

    NARCIS (Netherlands)

    Broek, T.H.A. van den; Netten, B.D.; Hoedemaeker, M.; Ploeg, J.

    2010-01-01

    In this paper, a large field operational test (FOT) for cooperative driving systems, which take place on a public highway, is discussed. The experimental setup consist of a specific driver support system, which is closely related to cooperative adaptive cruise control (CACC) systems. Instead of auto

  18. Test of a cryogenic set-up for a 10 meter long liquid nitrogen cooled superconducting power cable

    DEFF Research Database (Denmark)

    Træholt, Chresten; Rasmussen, Carsten; Kühle (fratrådt), Anders Van Der Aa;

    2000-01-01

    High temperature superconducting power cables may be cooled by a forced flow of sub-cooled liquid nitrogen. One way to do this is to circulate the liquid nitrogen (LN2) by means of a mechanical pump through the core of the cable and through a sub-cooler.Besides the cooling station, the cryogenics...... cable. We report on our experimental set-up for testing a 10 meter long high temperature superconducting cable with a critical current of 3.2 kA at 77K. The set-up consists of a custom designed cable end termination, current lead, coolant feed-through, liquid nitrogen closed loop circulation system...

  19. Fatigue testing of materials under extremal conditions by acoustic method

    NARCIS (Netherlands)

    Baranov, VM; Bibilashvili, YK; Karasevich, VA; Sarychev, GA

    2004-01-01

    Increasing fuel cycle time requires fatigue testing of the fuel clad materials for nuclear reactors. The standard high-temperature fatigue tests are complicated and tedious. Solving this task is facilitated by the proposed acoustic method, which ensures observation of the material damage dynamics, m

  20. A comparison of acoustic and random vibration testing of spacecraft

    Science.gov (United States)

    Bangs, W. F.

    1974-01-01

    Before selecting the most suitable testing technique in a particular case, it has to be considered which of the two methods duplicates better the distribution of vibration responses to be expected during the actual launch phase. An investigation is conducted of the case of a large, low density spacecraft launched by a vehicle which produces significant acoustic noise and transmits relatively little vibration through the mechanical path provided by the vehicle structure in the area of the spacecraft interface. Criteria for vibration-acoustic equivalence are discussed along with tests conducted with the Synchronous Meteorological Satellite, the Radio Astronomy Explorer, and the Orbiting Geophysical Spacecraft. The investigation indicates that the vibration test is generally a poor substitute for an acoustic study.-

  1. Vibration and acoustic testing of TOPEX/Poseidon satellite

    Science.gov (United States)

    Boatman, Dave; Scharton, Terry; Hershfeld, Donald; Larkin, Paul

    1992-01-01

    The satellite was subjected to a 1.5G swept sine vibration test and a 146 dB overall level acoustic test, in accordance with Ariane launch vehicle requirements, at the NASA Goddard Space Flight Center. Extensive pretest analysis of the sine test was conducted to plan the input notching and to justify vibration testing the satellite only in the longitudinal axis. A unique measurement system was utilized to determine the six components of interface force between the shaker and the satellite in the sine vibration test. The satellite was heavily instrumented in both the sine vibration and acoustic test in order to insure that the launch loads were enveloped with appropriate margin and that satellite responses did not exceed the compatibilities of the structure and equipment. The test specification, objectives, instrumentation, and test results are described herein.

  2. Early diagnosis of acoustic neuroma by the vestibular test

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-11-01

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

  3. A test beam setup for the characterization of the Geiger-mode avalanche photodiode technology for particle tracking

    Energy Technology Data Exchange (ETDEWEB)

    Vilella, E., E-mail: evilella@el.ub.es [Department of Electronics, University of Barcelona (UB), C/Marti i Franques 1, 08028 Barcelona (Spain); Alonso, O. [Department of Electronics, University of Barcelona (UB), C/Marti i Franques 1, 08028 Barcelona (Spain); Trenado, J. [Department of Structure and Constituents of Matter, University of Barcelona (UB), C/Marti i Franques 1, 08028 Barcelona (Spain); Vila, A.; Casanova, R. [Department of Electronics, University of Barcelona (UB), C/Marti i Franques 1, 08028 Barcelona (Spain); Vos, M. [Instituto de Fisica Corpuscular (IFIC), C/Catedratico Jose Beltran 2, 46980 Paterna (Spain); Garrido, L. [Department of Structure and Constituents of Matter, University of Barcelona (UB), C/Marti i Franques 1, 08028 Barcelona (Spain); Dieguez, A. [Department of Electronics, University of Barcelona (UB), C/Marti i Franques 1, 08028 Barcelona (Spain)

    2012-12-01

    It is well known that avalanche photodiodes operated in the Geiger mode above the breakdown voltage offer a virtually infinite gain and time accuracy in the picosecond range that can be used for single photon detection. However, their performance in particle detection still remains unexplored. In this contribution, we are going to expose different steps that we have taken in order to prove the efficiency of the Geiger mode avalanche photodiodes in the aforementioned field. In particular, we will present a setup for the characterization of these sensors in a test beam. The expected results of the test beam at DESY and CERN have been simulated with Geant4 and will also be exposed. -- Highlights: Black-Right-Pointing-Pointer A Setup for characterization of the GAPD technology in a test beam is presented. Black-Right-Pointing-Pointer Two test beams at DESY (6 GeV) and CERN (120 GeV) are already planned at current time. Black-Right-Pointing-Pointer A GAPD array has been designed and fabricated to fit the test beam requirements. Black-Right-Pointing-Pointer We have prepared a test beam setup to minimize the particle multiscattering. Black-Right-Pointing-Pointer The Expected results at DESY and CERN have been simulated with Geant4.

  4. Developing a reproducible non-line-of-sight experimental setup for testing wireless medical device coexistence utilizing ZigBee.

    Science.gov (United States)

    LaSorte, Nickolas J; Rajab, Samer A; Refai, Hazem H

    2012-11-01

    The integration of heterogeneous wireless technologies is believed to aid revolutionary healthcare delivery in hospitals and residential care. Wireless medical device coexistence is a growing concern given the ubiquity of wireless technology. In spite of this, a consensus standard that addresses risks associated with wireless heterogeneous networks has not been adopted. This paper serves as a starting point by recommending a practice for assessing the coexistence of a wireless medical device in a non-line-of-sight environment utilizing 802.15.4 in a practical, versatile, and reproducible test setup. This paper provides an extensive survey of other coexistence studies concerning 802.15.4 and 802.11 and reports on the authors' coexistence testing inside and outside an anechoic chamber. Results are compared against a non-line-of-sight test setup. Findings relative to co-channel and adjacent channel interference were consistent with results reported in the literature.

  5. Exposure setup to test effects of wireless communications systems on the CNS.

    Science.gov (United States)

    Burkhardt, M; Spinelli, Y; Kuster, N

    1997-11-01

    This paper presents an exposure setup designed for in vivo studies of possible effects on the central nervous system due to the electromagnetic exposure from handheld mobile communications equipment. The setup consists of a carousel on which 10 rats, each restrained in a radially positioned tube, are exposed to the electromagnetic field emanating from a dipole antenna at the center. The rats are positioned with their snouts at a distance of 35 mm from the dipole antenna. The tubes restrain the movement of the animals to such an extent as to allow for well defined exposure conditions, yet without totally immobilizing them. Numerical and experimental dosimetric analysis of the setup was conducted using rats weighing 250-300 g at a frequency of 900 MHz. A detailed rat phantom derived from MRI scans was developed for the numerical assessment with a commercially available code based on the finite integration technique. The results were validated by measurements of the temperature rise in selected points of a rat cadaver. The dosimetric analysis shows that the setup is eminently suitable for central nervous system studies. It enables well defined field strengths to be induced in the brain tissue, whereby the variations in the specific absorption rate averaged over the brain tissue caused by movement and varying animal sizes was shown to be less than +/-16%. The specific absorption rate distribution in the brain is nonhomogeneous but comparable to that induced in the brain of a human using a handheld wireless phone. The efficiency of the exposure is about 0.20+/-0.05 mW g(-1) for the brain average value per 100 mA feedpoint current. The whole-body average specific absorption rate is considerably lower, i.e., about half of that of the brain averaged value. In addition, the setup has been proven to be practical in use, and the stress levels caused by restraining the animals in this setup are deemed by neurologists and veterinary scientists to be very low.

  6. Wake Shield Facility Modal Survey Test in Vibration Acoustic Test Facility

    Science.gov (United States)

    1994-01-01

    Astronaut Ronald M. Sega stands beside the University of Houston's Wake Shield Facility before it undergoes a Modal Survey Test in the Vibration and Acoustic Test Facility Building 49, prior to being flown on space shuttle mission STS-60.

  7. Development and Test of a Neutron Imaging Setup at the PGAA Instrument at FRM II

    OpenAIRE

    Söllradl, S.; M. J. Mühlbauer; Kudejova, P.; Türler, Andreas

    2015-01-01

    We report on the developments of a neutron tomography setup at the instrument for prompt gamma-ray activation analysis (PGAA) at the Maier-Leibnitz Zentrum(MLZ). The recent developments are driven by the idea of combining the spatial information obtained with neutron tomography with the elemental information determined with PGAA, i.e. to further combine both techniques to an investigative technique called prompt gamma activation imaging (PGAI).At the PGAA instrument, a cold neutron flux of up...

  8. An Evaluation of the Additional Acoustic Power Needed to Overcome the Effects of a Test-Article's Absorption during Reverberant Chamber Acoustic Testing of Spaceflight Hardware

    Science.gov (United States)

    Hozman, Aron D.; Hughes, William O.

    2014-01-01

    The exposure of a customers aerospace test-article to a simulated acoustic launch environment is typically performed in a reverberant acoustic test chamber. The acoustic pre-test runs that will ensure that the sound pressure levels of this environment can indeed be met by a test facility are normally performed without a test-article dynamic simulator of representative acoustic absorption and size. If an acoustic test facilitys available acoustic power capability becomes maximized with the test-article installed during the actual test then the customers environment requirement may become compromised. In order to understand the risk of not achieving the customers in-tolerance spectrum requirement with the test-article installed, an acoustic power margin evaluation as a function of frequency may be performed by the test facility. The method for this evaluation of acoustic power will be discussed in this paper. This method was recently applied at the NASA Glenn Research Center Plum Brook Stations Reverberant Acoustic Test Facility for the SpaceX Falcon 9 Payload Fairing acoustic test program.

  9. Acoustic vibration test detects intermittent electrical discontinuities

    Science.gov (United States)

    Grieve, S. M.; Roberts, D. E.

    1970-01-01

    Nondestructive test method detects faulty electrical connections in inaccessible or hidden portions of electronic harness assemblies and connectors. Method employs readily available commercial equipment.

  10. The influence of laboratory set-up in usability tests: effects on user performance, subjective ratings and physiological measures.

    Science.gov (United States)

    Sonderegger, Andreas; Sauer, Juergen

    2009-11-01

    This article examines the influences of situational factors on user behaviour in usability tests. Sixty participants carried out two tasks on a computer-simulated prototype of a mobile phone. Employing a 3 x 2 mixed experimental design, laboratory set-up was varied as a between-subjects variable (presence of facilitator and two non-interactive observers, presence of facilitator or no person present) while task difficulty was manipulated as a within-subjects variable (low vs. high). Performance data, subjective measures and physiological parameters (e.g. heart rate variability) were taken. The results showed that the presence of non-interactive observers during a usability test led to a physiological stress response, decreased performance on some measures and affected the emotional state of test participants. The presence of a facilitator (i.e. a participating observer) also influenced the emotional state of the test participant. Practitioners involved in usability testing need to be aware of undue influences of observers, in particular, if the observers are non-interactive. The findings presented in this paper have implications for the practice of usability testing. They indicated a considerable influence of observers on test participants (physiology and emotions) and on the outcomes of usability tests (performance measures). This should be considered when selecting the set-up of a usability testing procedure.

  11. Structural tests using a MEMS acoustic emission sensor

    Science.gov (United States)

    Oppenheim, Irving J.; Greve, David W.; Ozevin, Didem; Hay, D. Robert; Hay, Thomas R.; Pessiki, Stephen P.; Tyson, Nathan L.

    2006-03-01

    In a collaborative project at Lehigh and Carnegie Mellon, a MEMS acoustic emission sensor was designed and fabricated as a suite of six resonant-type capacitive transducers in the frequency range between 100 and 500 kHz. Characterization studies showed good comparisons between predicted and experimental electro-mechanical behavior. Acoustic emission events, simulated experimentally in steel ball impact and in pencil lead break tests, were detected and source localization was demonstrated. In this paper we describe the application of the MEMS device in structural testing, both in laboratory and in field applications. We discuss our findings regarding housing and mounting (acoustic coupling) of the MEMS device with its supporting electronics, and we then report the results of structural testing. In all tests, the MEMS transducers were used in parallel with commercial acoustic emission sensors, which thereby serve as a benchmark and permit a direct observation of MEMS device functionality. All tests involved steel structures, with particular interest in propagation of existing cracks or flaws. A series of four laboratory tests were performed on beam specimens fabricated from two segments (Grade 50 steel) with a full penetration weld (E70T-4 electrode material) at midspan. That weld region was notched, an initial fatigue crack was induced, and the specimens were then instrumented with one commercial transducer and with one MEMS device; data was recorded from five individual transducers on the MEMS device. Under a four-point bending test, the beam displayed both inelastic behavior and crack propagation, including load drops associated with crack instability. The MEMS transducers detected all instability events as well as many or most of the acoustic emissions occurring during plasticity and stable crack growth. The MEMS transducers were less sensitive than the commercial transducer, and did not detect as many events, but the normalized cumulative burst count obtained

  12. Ares I Scale Model Acoustic Test Above Deck Water Sound Suppression Results

    Science.gov (United States)

    Counter, Douglas D.; Houston, Janice D.

    2011-01-01

    The Ares I Scale Model Acoustic Test (ASMAT) program test matrix was designed to determine the acoustic reduction for the Liftoff acoustics (LOA) environment with an above deck water sound suppression system. The scale model test can be used to quantify the effectiveness of the water suppression system as well as optimize the systems necessary for the LOA noise reduction. Several water flow rates were tested to determine which rate provides the greatest acoustic reductions. Preliminary results are presented.

  13. Design of the Testing Set-up for a Nuclear Fuel Rod by Neutron Radiography at CARR

    Science.gov (United States)

    Wei, Guohai; Han, Songbai; Wang, Hongli; Hao, Lijie; Wu, Meimei; He, Linfeng; Wang, Yu; Liu, Yuntao; Sun, Kai; Chen, Dongfeng

    In this paper, an experimental set-up dedicated to non-destructively test a 15cm-long Pressurized Water Reactor (PWR) nuclear fuel rod by neutron radiography (NR) is described. It consists of three parts: transport container, imaging block and steel support. The design of the transport container was optimized with Monte-Carlo Simulation by the MCNP code. The material for the shell of the transport container was chosen to be lead with the thickness of 13 cm. Also, the mechanical devices were designed to control fuel rod movement inside the container. The imaging block was designed as the exposure platform, with three openings for the neutron beam, neutron converter foil, and specimen. Development and application of this experimental set-up will help gain much experience for investigating the actual irradiated fuel rod by neutron radiography at CARR in the future.

  14. Beta Testing of Persistent Passive Acoustic Monitors

    Science.gov (United States)

    2012-10-01

    solution. This translates into longer deployments on platforms such as gliders with limited hotel load. 2. the DMON is specifically designed for low...filter or filter bank may improve performance • Glider and Profiler motors and pumps are noisy , however duty cycle of noise is low. Therefore they are...power making it ideal for low hotel load autonomous vehicles like gliders. The format shown here was provided to beta-test clients working on gliders and

  15. Acoustic conditions in open plan offices – Pilot test results

    Directory of Open Access Journals (Sweden)

    Witold Mikulski

    2016-10-01

    Full Text Available Background: The main source of noise in open plan office are conversations. Office work standards in such premises are attained by applying specific acoustic adaptation. This article presents the results of pilot tests and acoustic evaluation of open space rooms. Material and Methods: Acoustic properties of 6 open plan office rooms were the subject of the tests. Evaluation parameters, measurement methods and criterial values were adopted according to the following standards: PN-EN ISO 3382- 3:2012, PN-EN ISO 3382-2:2010, PN-B-02151-4:2015-06 and PN-B-02151-3:2015-10. Results: The reverberation time was 0.33– 0.55 s (maximum permissible value in offices – 0.6 s; the criterion was met, sound absorption coefficient in relation to 1 m2 of the room’s plan was 0.77–1.58 m2 (minimum permissible value – 1.1 m2; 2 out of 6 rooms met the criterion, distraction distance was 8.5–14 m (maximum permissible value – 5 m; none of the rooms met the criterion, A-weighted sound pressure level of speech at a distance of 4 m was 43.8–54.7 dB (maximum permissible value – 48 dB; 2 out of 6 rooms met the criterion, spatial decay rate of the speech was 1.8–6.3 dB (minimum permissible value – 7 dB; none of the rooms met the criterion. Conclusions: Standard acoustic treatment, containing sound absorbing suspended ceiling, sound absorbing materials on the walls, carpet flooring and sound absorbing workplace barriers, is not sufficient. These rooms require specific advanced acoustic solutions. Med Pr 2016;67(5:653–662

  16. ATLAS TileCal Sub-Module Production at UIUC - Photos of Prototype PMT Test Setup

    CERN Multimedia

    Errede, Steve

    2001-01-01

    Photo 1 - Entrance to the lab. Photo 2 - A shot of the center of the lab. Photo 3 - The back of the lab. The Dark Box: Photo 4 - A view of the outside of the Dark Box along with its dry nitrogen system. Photo 5 - A view of the inside of the Dark Box. Photo 6 - The LED holder, beam splitter (removed in this shot), and a pulsing circuit. Photo 7 - The PMT holder. Photo 8 - A possible design for a Stepper Motor controlled filter wheel. Photo 9 - Polishing area for the optical fibers. R&D Work on Stepper Motor/Motion Control: Photo 10 - The complete prototype of the Stepper Motor setup. Photo 11 - The prototype of the Main Stepper Motor Driver Board. Photo 12 - The prototype of the Stepper Motor Power Amplifer. Photo 13 - The prototype of the Stepper Motor LabPC + Interface Board.

  17. Acoustic tests of Lorentz symmetry using Bulk Acoustic Wave quartz oscillators

    CERN Document Server

    Goryachev, M; Haslinger, Ph; Mizrachi, E; Anderegg, L; Müller, H; Hohensee, M; Tobar, M E

    2016-01-01

    A new method of probing Lorentz invariance in the neutron sector is described. The method is baed on stable quartz bulk acoustic wave oscillators compared on a rotating table. Due to Lorentz-invariance violation, the resonance frequencies of acoustic wave resonators depend on the direction in space via a corresponding dependence of masses of the constituent elements of solids. This dependence is measured via observation of oscillator phase noise built around such devices. The first such experiment now shows sensitivity to violation down to the limit $\\tilde{c}^n_Q=(-1.8\\pm2.2)\\times 10^{-14}$ GeV. Methods to improve the sensitivity are described together with some other applications of the technology in tests of fundamental physics.

  18. A setup to perform X-ray irradiation tests on scintillating fibres for the SciFi project

    CERN Document Server

    Gavardi, Laura; Joram, Christian; Kristic, Robert

    2017-01-01

    An X-ray setup has been installed at CERN. The setup will serve for quality assurance purposes related to the acceptance of $11'000~ \\text{km}$ of scintillating plastic fibres for the SciFi detector of LHCb. The X-ray tube has a tungsten target and can be powered up to 60kV, 30mA. The setup is intended to monitor the relative radiation response of the different fibre batches. The dose rate absorbed by the fibre under test can be tuned, adjusting the settings of the X-ray tube and adding aluminium filters of different thicknesses. When operating the X-ray tube without filters at a high voltage of $40\\rm \\,kV$ and an anode current of $30\\rm \\,mA$, the dose rate is about $23\\rm \\,Gy/min$. The maximum dose of about $35\\rm \\,kGy$ expected in the SciFi Tracker can be thus reached in about $1\\rm \\,day$.

  19. Acoustic interactions between an altitude test facility and jet engine plumes: Theory and experiments

    Science.gov (United States)

    Ahuja, K. K.; Jones, R. R., III; Tam, C. K.; Massey, K. C.; Fleming, A. J.

    1992-01-01

    The overall objective of the described effort was to develop an understanding of the physical mechanisms involved in the flow/acoustic interactions experienced in full-scale altitude engine test facilities. This is done by conducting subscale experiments and through development of a theoretical model. Model cold jet experiments with an axisymmetric convergent nozzle are performed in a test setup that stimulates a supersonic jet exhausting into a cylindrical diffuser. The measured data consist of detailed flow visualization data and acoustic spectra for a free and a ducted plume. It is shown that duct resonance is most likely responsible by theoretical calculations. Theoretical calculations also indicate that the higher discrete tones observed in the measurements are related to the screech phenomena. Limited experiments on the sensitivity of a free 2-D, C-D nozzle to externally imposed sound are also presented. It is shown that a 2-D, C-D nozzle with a cutback is less excitable than a 2-D C-D nozzle with no cutback. At a pressure ratio of 1.5 unsteady separation from the diverging walls of the nozzle is noticed. This separation switches from one wall to the opposite wall thus providing an unsteady deflection of the plume. It is shown that this phenomenon is related to the venting provided by the cutback section.

  20. Measurement of acoustic attenuation in South Pole ice

    NARCIS (Netherlands)

    Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguilar, J.A.; Ahlers, M.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S.W.; Bay, R.; Alba, J.L.B.; Beattie, K.; Beatty, J.J.; Bechet, S.; Becker, J.K.; Becker, K.H.; Benabderrahmane, M.L.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D.Z.; Bissok, M.; Blaufuss, E.; Boersma, D.J.; Bohm, C.; Boser, S.; Botner, O.; Bradley, L.; Braun, J.; Buitink, S.; Carson, M.; Chirkin, D.; Christy, B.; Clem, J.; Clevermann, F.; Cohen, S.; Colnard, C.; Cowen, D.F.; D'Agostino, M.V.; Danninger, M.; Clercq, C. De; Demirors, L.; Depaepe, O.; Descamps, F.; Desiati, P.; Vries-Uiterweerd, G. de; DeYoung, T.; Diaz-Velez, J.C.; Dreyer, J.; Dumm, J.P.; Duvoort, M.R.; Ehrlich, R.; Eisch, J.; Ellsworth, R.W.; Engdegard, O.; Euler, S.; Evenson, P.A.; Fadiran, O.; Fazely, A.R.; Feusels, T.; Filimonov, K.; Finley, C.; Foerster, M.M.; Fox, B.D.; Franckowiak, A.; Franke, R.; Gaisser, T.K.; Gallagher, J.; Ganugapati, R.; Geisler, M.; Gerhardt, L.; Gladstone, L.; Glusenkamp, T.; Goldschmidt, A.; Goodman, J.A.; Grant, D.; Griesel, T.; Gross, A.; Grullon, S.; Gunasingha, R.M.; Gurtner, M.; Gustafsson, L.; Ha, C.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Helbing, K.; Herquet, P.; Hickford, S.; Hill, G.C.; Hoffman, K.D.; Homeier, A.; Hoshina, K.; Hubert, D.; Huelsnitz, W.; Lafebre, S.J.

    2011-01-01

    Using the South Pole Acoustic Test Setup (SPATS) and a retrievable transmitter deployed in holes drilled for the IceCube experiment, we have measured the attenuation of acoustic signals by South Pole ice at depths between 190 m and 500 m. Three data sets, using different acoustic sources, have been

  1. NASA Engineering and Safety Center (NESC) Enhanced Melamine (ML) Foam Acoustic Test (NEMFAT)

    Science.gov (United States)

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

    2014-01-01

    The NASA Engineering and Safety Center (NESC) funded a proposal to achieve initial basic acoustic characterization of ML (melamine) foam, which could serve as a starting point for a future, more comprehensive acoustic test program for ML foam. A project plan was developed and implemented to obtain acoustic test data for both normal and enhanced ML foam. This project became known as the NESC Enhanced Melamine Foam Acoustic Test (NEMFAT). This document contains the outcome of the NEMFAT project.

  2. Test setup for accelerated test of high power IGBT modules with online monitoring of Vce and Vf voltage during converter operation

    DEFF Research Database (Denmark)

    de Vega, Angel Ruiz; Ghimire, Pramod; Pedersen, Kristian Bonderup;

    2014-01-01

    of the device in real application. The hypothesis is that ageing of power modules closer to real environment including cooling system, full dc-link voltage and continuous PWM operation could lead to more accurate study of failure mechanism. A new type of test setup is proposed, which can create different real...

  3. Is reverberation time adequate for testing the acoustical quality of unroofed auditoriums?

    DEFF Research Database (Denmark)

    Paini, Dario; Gade, Anders Christian; Rindel, Jens Holger

    2006-01-01

    30) and other acoustical parameters normally used to test the acoustical quality of closed auditoria, such as concert halls, theatres, opera houses, are suitable and sufficient for testing the acoustical quality of open performance spaces. Simulations as well as measurements were carried out to study...

  4. Setup a photomultiplier tube test bench for use at LHAASO-KM2A

    CERN Document Server

    Wang, Xu; Tian, Ye; Li, Changyu; Sun, Yansheng; Feng, Cunfeng

    2015-01-01

    To fulfill the requirements of testing the photomultiplier tubes of the electromagnetic detector at the Large High Altitude Air Shower Observatory (LHAASO), a multi-functional PMT test bench with a two-dimensional scanning system is developed. With this 2D scanning system, 16 PMTs are scanned simultaneously to test their uniformity and cathode transit time difference, and we can also perform PMT tests of SPE spectrum, gain vs. high voltage, linear behavior and dark noise. The programmable hardware and intelligent software of the test bench make it convenient to use and provide reliable results. The test methods are described in detail and primary results are presented.

  5. Quality Testing of Gaseous Helium Pressure Vessels by Acoustic Emission

    CERN Document Server

    Barranco-Luque, M; Hervé, C; Margaroli, C; Sergo, V

    1998-01-01

    The resistance of pressure equipment is currently tested, before commissioning or at periodic maintenance, by means of normal pressure tests. Defects occurring inside materials during the execution of these tests or not seen by usual non-destructive techniques can remain as undetected potential sources of failure . The acoustic emission (AE) technique can detect and monitor the evolution of such failures. Industrial-size helium cryogenic systems employ cryogens often stored in gaseous form under pressure at ambient temperature. Standard initial and periodic pressure testing imposes operational constraints which other complementary testing methods, such as AE, could significantly alleviate. Recent reception testing of 250 m3 GHe storage vessels with a design pressure of 2.2 MPa for the LEP and LHC cryogenic systems has implemented AE with the above-mentioned aims.

  6. Specification of a cyclist target and test setup for the evaluation of Cyclist-AEB systems

    NARCIS (Netherlands)

    Montfort, S. van; Camp, O.M.G.C. op den; Fritz, M.; Wimmer, T.

    2015-01-01

    From 2018, AEB systems dedicated to avoid or mitigate car-to-cyclist collisions will be included in the safety assessment by Euro NCAP [1] & [2]. To test such systems, appropriate equipment and a test procedure are being developed in the project CATS (Cyclist-AES Testing System). Accidentology was u

  7. Vibration and Acoustic Test Facility (VATF): User Test Planning Guide

    Science.gov (United States)

    Fantasia, Peter M.

    2011-01-01

    Test process, milestones and inputs are unknowns to first-time users of the VATF. The User Test Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their test engineering personnel in test planning and execution. Material covered includes a roadmap of the test process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, test article interfaces, and inputs necessary to define test scope, cost, and schedule are included as an appendix to the guide.

  8. An Evaluation of the Additional Acoustic Power Needed to Overcome the Effects of a Test-Articles Absorption During Reverberant Chamber Acoustic Testing of Spaceflight Hardware

    Science.gov (United States)

    Hozman, Aron D.; Hughes, William O.

    2014-01-01

    It is important to realize that some test-articles may have significant sound absorption that may challenge the acoustic power capabilities of a test facility. Therefore, to mitigate this risk of not being able to meet the customers target spectrum, it is prudent to demonstrate early-on an increased acoustic power capability which compensates for this test-article absorption. This paper describes a concise method to reduce this risk when testing aerospace test-articles which have significant absorption. This method was successfully applied during the SpaceX Falcon 9 Payload Fairing acoustic test program at the NASA Glenn Research Center Plum Brook Stations RATF.

  9. Love wave acoustic sensor for testing in liquids

    Science.gov (United States)

    Pan, Haifeng; Zhu, Huizhong; Feng, Guanping

    2001-09-01

    Love wave is one type of the surface acoustic waves (SAWs). It is guided acoustic mode propagating in ta thin layer deposited on a substrate. Because of its advantages of high mass sensitivity, low noise level and being fit for operating in liquids, Love wave acoustic sensors have become one of the hot spots in the research of biosensor nowadays. In this paper the Love wave devices with the substrate of ST-cut quartz and the guiding layers of PMMA and fused quartz were fabricated successfully. By measuring the transfer function S21 and the insertion loss of the devices, the characteristics of the Rayleigh wave device and the Love wave devices with different guiding layers in gas phase and liquid phase were compared. It was validated that the Love wave sensor is suitable for testing in liquids but the Rayleigh wave sensor is not. What's more, SiO2 is the more proper material for the guiding layer of the Love wave device.

  10. Potential of acoustic emissions from three point bending tests as rock failure precursors

    Institute of Scientific and Technical Information of China (English)

    Agioutantis Z.; Kaklis K.; Mavrigiannakis S.; Verigakis M.; Vallianatos F.; Saltas V.

    2016-01-01

    Development of failure in brittle materials is associated with microcracks, which release energy in the form of elastic waves called acoustic emissions. This paper presents results from acoustic emission mea-surements obtained during three point bending tests on Nestos marble under laboratory conditions. Acoustic emission activity was monitored using piezoelectric acoustic emission sensors, and the potential for accurate prediction of rock damage based on acoustic emission data was investigated. Damage local-ization was determined based on acoustic emissions generated from the critically stressed region as scat-tered events at stresses below and close to the strength of the material.

  11. Towards nondestructive testing of pre-crash systems in a HIL setup

    NARCIS (Netherlands)

    Ploeg, J.; Hendriks, F.M.; Schouten, N.J.

    2008-01-01

    Recently, the developments in the field of ADA systems shifted from comfort oriented systems to safety oriented systems. Consequently, the complexity of testing those systems increased. This leads to a demand for reproducible, efficient and safe testing methods for ADA systems in general, and pre-cr

  12. A test beam set-up for the characterization of the Geiger-mode avalanche photodiode technology for particle tracking

    CERN Document Server

    Vilella, A; Trenado, J; Vila, A; Casanova, R; Vos, M; Garrido, L; Dieguez, A

    2012-01-01

    It is well known that avalanche photodiodes operated in the Geiger mode above the breakdown voltage offer a virtually infinite gain and time accuracy in the picosecond range that can be used for single photon detection. However, their performance in particle detection still remains unexplored. In this contribution, we are going to expose different steps that we have taken in order to prove the efficiency of the Geiger mode avalanche photodiodes in the aforementioned field. In particular, we will present a setup for the characterization of these sensors in a test beam. The expected results of the test beam at DESY and CERN have been simulated with Geant4 and will also be exposed.

  13. Test setup for long term reliability investigation of Silicon Carbide MOSFETs

    DEFF Research Database (Denmark)

    Baker, Nick; Munk-Nielsen, Stig; Beczkowski, Szymon

    2013-01-01

    Silicon Carbide MOSFETs are now widely available and have frequently been demonstrated to offer numerous advantages over Silicon based devices. However, reliability issues remain a significant concern in their realisation in commercial power electronic systems. In this paper, a test bench...... is designed that enables an accelerated power cycling test to be performed on packaged Silicon Carbide MOSFETs (TO-247) under realistic operating conditions. An accelerated power cycling test is then performed, with on-state resistance selected as the observed parameter to detect degradation. On......-state resistance is routinely monitored online through the use of an innovative voltage measurement system. The packaged Silicon Carbide MOSFET is shown to exhibit a 25% increase in on-state resistance as the device ages throughout its lifetime, with the test still on-going....

  14. Acoustic monitoring systems tests at Indian Point Unit 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.R.; Rao, G.V.; Craig, J.

    1979-12-01

    This report describes the results of a program to test acoustic monitoring systems on Indian Point Unit No. 1 under actual plant operating conditions, less the reactor core. The two types of systems evaluated were the monitoring of acoustic emissions generated by growing flaws and the monitoring of acoustic signals from leaks.

  15. Design and building of a new experimental setup for testing hydrogen storage materials

    DEFF Research Database (Denmark)

    Andreasen, A.

    2005-01-01

    For hydrogen to become the future energy carrier a suitable way of storing hydrogen is needed, especially if hydrogen is to be used in mobile applications such as cars. To test potential hydrogen storage materials with respect to capacity, kinetics andthermodynamics the Materials Research...

  16. Verification of Emulated Channels in Multi-Probe Based MIMO OTA Testing Setup

    DEFF Research Database (Denmark)

    Fan, Wei; Carreño, Xavier; Nielsen, Jesper Ødum;

    2013-01-01

    Standardization work for MIMO OTA testing methods is currently ongoing, where a multi-probe anechoic chamber based solution is an important candidate. In this paper, the probes located on an OTA ring are used to synthesize a plane wave field in the center of the OTA ring. This paper investigates...... the extent to which we can approach the synthesized plane wave in practical measurement systems. Both single plane wave with certain AoA and multiple plane waves with different AoAs and power weightings are synthesized and measured. Deviations of the measured plane wave and the simulated plane wave field...

  17. Infrared Thermography Assessment of Thermal Bridges in Building Envelope: Experimental Validation in a Test Room Setup

    Directory of Open Access Journals (Sweden)

    Francesco Bianchi

    2014-10-01

    Full Text Available Thermal infrared imaging is a valuable tool to perform non-destructive qualitative tests and to investigate buildings envelope thermal-energy behavior. The assessment of envelope thermal insulation, ventilation, air leakages, and HVAC performance can be implemented through the analysis of each thermogram corresponding to an object surface temperature. Thermography also allows the identification of thermal bridges in buildings’ envelope that, together with windows and doors, constitute one of the weakest component increasing thermal losses. A quantitative methodology was proposed in previous researches by the authors in order to evaluate the effect of such weak point on the energy balance of the whole building. In the present work, in-field experimental measurements were carried out with the purpose of evaluating the energy losses through the envelope of a test room experimental field. In-situ thermal transmittance of walls, ceiling and roof were continuously monitored and each element was characterized by its own thermal insulation capability. Infrared thermography and the proposed quantitative methodology were applied to assess the energy losses due to thermal bridges. The main results show that the procedure confirms to be a reliable tool to quantify the incidence of thermal bridges in the envelope thermal losses.

  18. Space Station and Shuttle Payloads: Rack Insertion Device Pneumatic Assembly Setup and Test

    Science.gov (United States)

    Conde, Nathan

    2007-01-01

    As part of my KSC summer internship, I was given the very cool task of writing a test preparation sheet (TPS). A TPS is a set of instructions for certain procedures or tasks, and serves as the documentation for the tasks. TPSs guide task leaders and technicians throughout the work procedures, safely, informing them of what steps will be hazardous, what precautions must be taken, and what to do in the case of an accident or emergency. I was placed in Boeing's Resupply & Return Division (R&R). R&R is responsible for sending up food and supplies to the International Space Station (ISS) with the use of three Italian Multi Purpose Logistics Modules - Leonardo, Donatello, and Raffaello. The supplies are loaded into Resupply Stowage Racks (RSRs) or Resupply Stowage Platforms (RSPs) (though, both are usually referred to as racks), depending on their size and shape. These racks are loaded into the modules with the help of a specialized crane known as the Rack Insertion Device (RID). The RID rests on four pneumatic air jacks, these allow for an operator to raise or lower the RID. The pneumatic air system supplies the air jacks with the necessary air pressure required to lift the RID.

  19. Automation of call setup in IP telephony for tests and measurements

    Science.gov (United States)

    Khasnabish, Bhumip

    1999-11-01

    In IP telephony, a call is usually established in multiple stages. In the first stage, an ingress or call-originating IP-PSTN gateway (GW) is accessed. This is followed by a PIN based caller authentication. Finally, a destination telephone number is entered. If the GWs have enough digital signal processing channels and processing capacity, and the backbone (transport) network can support one T1 CAS port's worth of calls, we should be able to simultaneously start 24 voice connection attempts. The call originating GW should be able to process all the 24 connection requests. However, it appears that most of the currently available IP-PSTN GWs can not handle all 24 simultaneous connection requests. Therefore it is necessary to develop a method to determine the number of calls that can be started simultaneously. It is also required to determine the amount of inter call-burst time gap (in millisec. or sec.) so that all 24 calls will be processed using the existing hardware and software configuration and capacity of the GW. In this paper we develop techniques to perform both of the above functions. These are implemented using Hammer visual basic language for testing some commercially available IP telephony GWs.

  20. Development of a full scale remote steerable ECRH mm-wave launching system test set-up for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Elzendoorn, B.S.Q. [FOM Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, Nieuwegein, Edisonbaan 14, 3439 MN Nieuwegein (Netherlands)], E-mail: ben@rijnh.nl; Bongers, W.A.; Graswinckel, M.F. [FOM Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, Nieuwegein, Edisonbaan 14, 3439 MN Nieuwegein (Netherlands); Jamar, J. [TNO Science and Industry, Business Unit Design and Manufacturing, Eindhoven, P.O. Box 6235, 5600 HE Eindhoven (Netherlands); Kruijt, O.G.; Lamers, B.; Ronden, D.M.S. [FOM Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, Nieuwegein, Edisonbaan 14, 3439 MN Nieuwegein (Netherlands); Verhoeven, A.G.A

    2007-10-15

    FOM is developing a full-scale mock-up of the mm-wave upper-port launching system for electron cyclotron resonance heating in ITER. The test set-up foresees in most of the typical ITER operation conditions, e.g. primary vacuum and the secondary vacuum, blanket cooling and component cooling conditions. All relevant operational ITER conditions except neutron radiation can be simulated, including baking conditions. The fabrication of the launching system mock-up will be the last step in the development phase, which will be characterized by the fabrication of test samples and mm-wave tests and calculations. The parameterized modeling of mm-wave beam propagation in CATIA [D.M.S. Ronden, et al., Parameterized modeling of mm-wave beam propagation of the ITER ECRH remote steering upper port launcher in CATIA, this conference] (8th figure in this article) the test and calculation results will be used for the built to print design of the remote steering ECRH launcher for the ITER upper ports [A.G.A. Verhoeven, et al., Design of the Remote Steering ITER ECRH Upper Port Launcher, this conference].

  1. Integration of Acoustic Detection Equipment into ANTARES

    CERN Document Server

    Lahmann, R; Graf, K; Hoessl, J; Kappes, A; Karg, T; Katz, U; Naumann, C; Salomon, K

    2005-01-01

    The ANTARES group at the University of Erlangen is working towards the integration of a set of acoustic sensors into the ANTARES Neutrino Telescope. With this setup, tests of acoustic particle detection methods and background studies shall be performed. The ANTARES Neutrino Telescope, which is currently being constructed in the Mediterranean Sea, will be equipped with the infrastructure to accommodate a 3-dimensional array of photomultipliers for the detection of Cherenkov light. Within this infrastructure, the required resources for acoustic sensors are available: Bandwidth for the transmission of the acoustic data to the shore, electrical power for the off-shore electronics and physical space to install the acoustic sensors and to route the connecting cables (transmitting signals and power) into the electronics containers. It will be explained how the integration will be performed with minimal modifications of the existing ANTARES design and which setup is foreseen for the acquisition of the acoustic data.

  2. Combined experimental-numerical characterisation of the vibro-acoustic properties of lightweight panels

    OpenAIRE

    De jonckheere, Stijn; Vivolo, Marianna; Pluymers, Bert; Vandepitte, Dirk; Desmet, Wim

    2012-01-01

    The presented paper focuses on a combined approach, using a new type of measurement setup, which has been specifically developed for examining the vibro-acoustic behaviour of lightweight panels and the Wave Based Method (WBM) for the numerical simulation of vibro-acoustic problems. The setup consists of a concrete cavity of 0.83 m³ which can host test specimens of variable size and thickness. It allows for both structural and acoustical excitation and measurement acquisition. Among others,...

  3. Integration of the Explorer Test Setup into the EuDAQ-Framework for Test-Beam Measurements

    CERN Document Server

    Augustin, Heiko Christian

    2013-01-01

    This is a short summary of my work done at CERN as my Summer Student Project, for the integration of a pixel sensor, the Explorer, into the test-beam framework for the EuDET telescope at DESY. The EuDAQ-Framework requires the software integration of the data readout of the sensor to make an easy analysis of the test-beam data possible. This software will be used during test-beam measurements later this year and can furthermore be easily adapted to different chip architectures.

  4. Numerical simulation of the tip aerodynamics and acoustics test

    Science.gov (United States)

    Tejero E, F.; Doerffer, P.; Szulc, O.; Cross, J. L.

    2016-04-01

    The application of an efficient flow control system on helicopter rotor blades may lead to improved aerodynamic performance. Recently, our invention of Rod Vortex Generators (RVGs) has been analyzed for helicopter rotor blades in hover with success. As a step forward, the study has been extended to forward flight conditions. For this reason, a validation of the numerical modelling for a reference helicopter rotor (without flow control) is needed. The article presents a study of the flow-field of the AH-1G helicopter rotor in low-, medium- and high-speed forward flight. The CFD code FLOWer from DLR has proven to be a suitable tool for the aerodynamic analysis of the two-bladed rotor without any artificial wake modelling. It solves the URANS equations with LEA (Linear Explicit Algebraic stress) k-ω model using the chimera overlapping grids technique. Validation of the numerical model uses comparison with the detailed flight test data gathered by Cross J. L. and Watts M. E. during the Tip Aerodynamics and Acoustics Test (TAAT) conducted at NASA in 1981. Satisfactory agreements for all speed regimes and a presence of significant flow separation in high-speed forward flight suggest a possible benefit from the future implementation of RVGs. The numerical results based on the URANS approach are presented not only for a popular, low-speed case commonly used in rotorcraft community for CFD codes validation but preferably for medium- and high-speed test conditions that have not been published to date.

  5. A Laboratory Test Setup for in Situ Measurements of the Dielectric Properties of Catalyst Powder Samples under Reaction Conditions by Microwave Cavity Perturbation: Set up and Initial Tests

    Directory of Open Access Journals (Sweden)

    Markus Dietrich

    2014-09-01

    Full Text Available The catalytic behavior of zeolite catalysts for the ammonia-based selective catalytic reduction (SCR of nitrogen oxides (NOX depends strongly on the type of zeolite material. An essential precondition for SCR is a previous ammonia gas adsorption that occurs on acidic sites of the zeolite. In order to understand and develop SCR active materials, it is crucial to know the amount of sorbed ammonia under reaction conditions. To support classical temperature-programmed desorption (TPD experiments, a correlation of the dielectric properties with the catalytic properties and the ammonia sorption under reaction conditions appears promising. In this work, a laboratory test setup, which enables direct measurements of the dielectric properties of catalytic powder samples under a defined gas atmosphere and temperature by microwave cavity perturbation, has been developed. Based on previous investigations and computational simulations, a resonator cavity and a heating system were designed, installed and characterized. The resonator cavity is designed to operate in its TM010 mode at 1.2 GHz. The first measurement of the ammonia loading of an H-ZSM-5 zeolite confirmed the operating performance of the test setup at constant temperatures of up to 300 °C. It showed how both real and imaginary parts of the relative complex permittivity are strongly correlated with the mass of stored ammonia.

  6. A laboratory test setup for in situ measurements of the dielectric properties of catalyst powder samples under reaction conditions by microwave cavity perturbation: set up and initial tests.

    Science.gov (United States)

    Dietrich, Markus; Rauch, Dieter; Porch, Adrian; Moos, Ralf

    2014-09-10

    The catalytic behavior of zeolite catalysts for the ammonia-based selective catalytic reduction (SCR) of nitrogen oxides (NOX) depends strongly on the type of zeolite material. An essential precondition for SCR is a previous ammonia gas adsorption that occurs on acidic sites of the zeolite. In order to understand and develop SCR active materials, it is crucial to know the amount of sorbed ammonia under reaction conditions. To support classical temperature-programmed desorption (TPD) experiments, a correlation of the dielectric properties with the catalytic properties and the ammonia sorption under reaction conditions appears promising. In this work, a laboratory test setup, which enables direct measurements of the dielectric properties of catalytic powder samples under a defined gas atmosphere and temperature by microwave cavity perturbation, has been developed. Based on previous investigations and computational simulations, a resonator cavity and a heating system were designed, installed and characterized. The resonator cavity is designed to operate in its TM010 mode at 1.2 GHz. The first measurement of the ammonia loading of an H-ZSM-5 zeolite confirmed the operating performance of the test setup at constant temperatures of up to 300 °C. It showed how both real and imaginary parts of the relative complex permittivity are strongly correlated with the mass of stored ammonia.

  7. The Ability to Structure Acoustic Material as a Measure of Musical Aptitude. 4. Experiences with Modifications of the Acoustic Structuring Test. Research Bulletin. No. 51.

    Science.gov (United States)

    Karma, Kai

    Four new versions of an acoustic structuring test were developed, administered, and analyzed in order to produce better tests and to contribute to better understanding of the abilities measured by these tests. The tests consist of tape recordings of patterns of musical notes played on an electric organ or an acoustic guitar. Item analyses and…

  8. Acoustic emission analysis as a non-destructive test procedure for fiber compound structures

    Science.gov (United States)

    Block, J.

    1983-01-01

    The concept of acoustic emission analysis is explained in scientific terms. The detection of acoustic events, their localization, damage discrimination, and event summation curves are discussed. A block diagram of the concept of damage-free testing of fiber-reinforced synthetic materials is depicted. Prospects for application of the concept are assessed.

  9. Titanium honeycomb acoustic lining structural and thermal test report. [for acoustic tailpipe for JT8D engine

    Science.gov (United States)

    Joynes, D.; Balut, J. P.

    1974-01-01

    The results are presented of static, fatigue and thermal testing of titanium honeycomb acoustic panels representing the acoustic tailpipe for the Pratt and Whitney Aircraft JT8D Refan engine which is being studied for use on the Boeing 727-200 airplane. Test specimens represented the engine and tailpipe flange joints, the rail to which the thrust reverser is attached and shear specimens of the tailpipe honeycomb. Specimens were made in four different batches with variations in configuration, materials and processes in each. Static strength of all test specimens exceeded the design ultimate load requirements. Fatigue test results confirmed that aluminum brazed titanium, as used in the Refan tailpipe design, meets the fatigue durability objectives. Quality of welding was found to be critical to life, with substandard welding failing prematurely, whereas welding within the process specification exceeded the panel skin life. Initial fatigue testing used short grip length bolts which failed prematurely. These were replaced with longer bolts and subsequent testing demonstrated the required life. Thermal tests indicate that perforated skin acoustic honeycomb has approximately twice the heat transfer of solid skin honeycomb.

  10. Sensitivity testing of the model set-up used for calculation of photochemical ozone creation potentials (POCP) under European conditions

    Energy Technology Data Exchange (ETDEWEB)

    Altenstedt, J.; Pleijel, K.

    1998-02-01

    Photochemical Ozone Creation Potentials (POCP) is a method to rank VOC, relative to other VOC, according to their ability to produce ground level ozone. To obtain POCP values valid under European conditions, a critical analysis of the POCP concept has been performed using the IVL photochemical trajectory model. The critical analysis has concentrated on three VOC (ethene, n-butane and o-xylene) and has analysed the effect on their POCP values when different model parameters were varied. The three species were chosen because of their different degradation mechanisms in the atmosphere and thus their different abilities to produce ozone. The model parameters which have been tested include background emissions, initial concentrations, dry deposition velocities, the features of the added point source and meteorological parameters. The critical analysis shows that the background emissions of NO{sub x} and VOC have a critical impact on the POCP values. The hour of the day for the point source emission also shows a large influence on the POCP values. Other model parameters which have been studied have not shown such large influence on the POCP values. Based on the critical analysis a model set-up for calculation of POCP is defined. The variations in POCP values due to changes in the background emissions of NO{sub x} and VOC are so large that they can not be disregarded in the calculation of POCP. It is recommended to calculate POCP ranges based on the extremes in POCP values instead of calculating site specific POCP values. Four individual emission scenarios which produced the extremes in POCP values in the analysis have been selected for future calculation of POCP ranges. The scenarios are constructed based on the emissions in Europe and the resulting POCP ranges are thus intended to be applicable within Europe 67 refs, 61 figs, 16 tabs

  11. Test of experimental set-ups for electrodialytic removal of Cu, Zn, Pb and Cd from different contaminated harbour sediments

    DEFF Research Database (Denmark)

    Nystrøm, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    of the sediment slurry, the other without stirring. The removal of heavy metals was highest in the non-calcareous sediment, where 94% Cd, 91% Zn and 73% Cu were removed after 24 days. The highest removal obtained for the calcareous sediment was 81% Cd, 76% Zn, 75% Pb and 53% Cu after 21 days, with stirred...... was the most stable in these experiments, and thus, the stirred set-up is the best choice for experimental set-up. The order in which the heavy metals were removed from the harbour sediments was Cd>Zn>Pb>Cu....

  12. Early diagnosis of acoustic neuroma by quantitative neurootological and neuroradiological tests

    Energy Technology Data Exchange (ETDEWEB)

    Haid, C.T.

    1983-02-01

    Every patient with unilateral and sensoneural loss of hearing, independent of vertigo anamnesis or X-rays must be further examined by a vestibular test. Between 1974 and 1980, 80 acoustic neuromas could be diagnosed, including 12 early stage neuromas. This relatively high detection quote of small neuromas is due to a special diagnostical program: All 80 patients with acoustic neuroma had a pathological vestibular result. The positional test turned out to be the most sensitive examination in the early diagnosis of acoustic neuromas and yields a still higher incidence than the caloric test: 95% of the patients with a neurinoma showed a pathological result in the positional test. So every patient suffering from an unidentified unilateral and sensoneural hearing loss combined with a pathological result in the positional test must be further examined by a cisternomeatography or computerized tomography (using air-insufflation). Every fifth of these patients showed unique hints of an acoustic neuroma in the neuroradiological test.

  13. A closed-loop automatic control system for high-intensity acoustic test systems.

    Science.gov (United States)

    Slusser, R. A.

    1973-01-01

    Sound at sound pressure levels in the range from 130 to 160 dB is used in the investigation. Random noise is passed through a series of parallel filters, generally 1/3-octave wide. A basic automatic system is investigated because of preadjustment inaccuracies and high costs found in a study of a typical manually controlled acoustic testing system. The unit described has been successfully used in automatic acoustic tests in connection with the spacecraft tests for the Mariner 1971 program.

  14. Reliable experimental setup to test the pressure modulation of Baerveldt Implant tubes for reducing post-operative hypotony

    Science.gov (United States)

    Ramani, Ajay

    Glaucoma encompasses a group of conditions that result in damage to the optic nerve and can cause loss of vision and blindness. The nerve is damaged due to an increase in the eye's internal (intraocular) pressure (IOP) above the nominal range of 15 -- 20 mm Hg. There are many treatments available for this group of diseases depending on the complexity and stage of nerve degradation. In extreme cases where drugs or laser surgery do not create better conditions for the patient, ophthalmologists use glaucoma drainage devices to help alleviate the IOP. Many drainage implants have been developed over the years and are in use; but two popular implants are the Baerveldt Glaucoma Implant and the Ahmed Glaucoma Valve Implant. Baerveldt Implants are non-valved and provide low initial resistance to outflow of fluid, resulting in post-operative complications such as hypotony, where the IOP drops below 5 mm of Hg. Ahmed Glaucoma Valve Implants are valved implants which initially restrict the amount of fluid flowing out of the eye. The long term success rates of Baerveldt Implants surpass those of Ahmed Valve Implants because of post-surgical issues; but Baerveldt Implants' initial effectiveness is poor without proper flow restriction. This drives the need to develop new ways to improve the initial effectiveness of Baerveldt Implants. A possible solution proposed by our research team is to place an insert in the Baerveldt Implant tube of inner diameter 305 microns. The insert must be designed to provide flow resistance for the early time frame [e.g., first 30 -- 60 post-operative days] until sufficient scar tissue has formed on the implant. After that initial stage with the insert, the scar tissue will provide the necessary flow resistance to maintain the IOP above 5 mm Hg. The main objective of this project was to develop and validate an experimental apparatus to measure pressure drop across a Baerveldt Implant tube, with and without inserts. This setup will be used in the

  15. Laboratory test and acoustic analysis of cabin treatment for propfan test assessment aircraft

    Science.gov (United States)

    Kuntz, H. L.; Gatineau, R. J.

    1991-01-01

    An aircraft cabin acoustic enclosure, built in support of the Propfan Test Assessment (PTA) program, is described. Helmholtz resonators were attached to the cabin trim panels to increase the sidewall transmission loss (TL). Resonators (448) were located between the trim panels and fuselage shell. In addition, 152 resonators were placed between the enclosure and aircraft floors. The 600 resonators were each tuned to a 235 Hz resonance frequency. After flight testing on the PTA aircraft, the enclosure was tested in the Kelly Johnson R and D Center Acoustics Lab. Laboratory noise reduction (NR) test results are discussed. The enclosure was placed in a Gulfstream 2 fuselage section. Broadband (138 dB overall SPL) and tonal (149 dB overall SPL) excitations were used in the lab. Tonal excitation simulated the propfan flight test excitation. The fundamental tone was stepped in 2 Hz intervals from 225 through 245 Hz. The resonators increase the NR of the cabin walls around the resonance frequency of the resonator array. The effects of flanking, sidewall absorption, cabin adsorption, resonator loading of trim panels, and panel vibrations are presented. Increases in NR of up to 11 dB were measured.

  16. Validation and Simulation of Ares I Scale Model Acoustic Test - 3 - Modeling and Evaluating the Effect of Rainbird Water Deluge Inclusion

    Science.gov (United States)

    Strutzenberg, Louise L.; Putman, Gabriel C.

    2011-01-01

    The Ares I Scale Model Acoustics Test (ASMAT) is a series of live-fire tests of scaled rocket motors meant to simulate the conditions of the Ares I launch configuration. These tests have provided a well documented set of high fidelity measurements useful for validation including data taken over a range of test conditions and containing phenomena like Ignition Over-Pressure and water suppression of acoustics. Building on dry simulations of the ASMAT tests with the vehicle at 5 ft. elevation (100 ft. real vehicle elevation), wet simulations of the ASMAT test setup have been performed using the Loci/CHEM computational fluid dynamics software to explore the effect of rainbird water suppression inclusion on the launch platform deck. Two-phase water simulation has been performed using an energy and mass coupled lagrangian particle system module where liquid phase emissions are segregated into clouds of virtual particles and gas phase mass transfer is accomplished through simple Weber number controlled breakup and boiling models. Comparisons have been performed to the dry 5 ft. elevation cases, using configurations with and without launch mounts. These cases have been used to explore the interaction between rainbird spray patterns and launch mount geometry and evaluate the acoustic sound pressure level knockdown achieved through above-deck rainbird deluge inclusion. This comparison has been anchored with validation from live-fire test data which showed a reduction in rainbird effectiveness with the presence of a launch mount.

  17. Use of Acoustic Emission During Scratch Testing for Understanding Adhesion Behavior of Aluminum Nitride Coatings

    Science.gov (United States)

    Choudhary, R. K.; Mishra, P.

    2016-06-01

    In this work, acoustic emission during scratch testing of the aluminum nitride coatings formed on stainless steel substrate by reactive magnetron sputtering was analyzed to assess the coating failure. The AlN coatings were formed under the variation of substrate temperature, substrate bias potential, and discharge power. The coatings deposited in the temperature range of 100 to 400 °C showed peak acoustic emission less than 1.5%, indicating ductile nature of the coating. However, for coatings formed with substrate negative bias potential of 20 to 50 V, numerous sharp acoustic bursts with maximum emission approaching 80% were observed, indicating brittle nature of the coatings with large number of defects present. The shift in the intensity of the first major acoustic peak toward higher load, with the increasing bias potential, confirmed improved adhesion of the coating. Also, the higher discharge power resulted in increased acoustic emission.

  18. A 24 channel acoustic/vibration test power amplifier

    Science.gov (United States)

    Barlett, F. R.

    1978-01-01

    In the present paper, the advantages and drawbacks of a multichannel amplifier operating in a vibration or acoustic facility are discussed. The configuration of the facility and the multichannel amplifier proposed is a compromise based on the particular requirements and anticipated work load in a specific case under consideration.

  19. 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.

    /plain; charset=ISO-8859-1 Acoustic communication for Maya Autonomous Underwater Vehicle - performance evaluation of acoustic modem. S. Afzulpurkar, P. Maurya, G. Navelkar, E. Desa, A. Mascarenhas, N. Dabholkar, R. Madhan 1 , S. Prabhudesai... factors that can be tweaked to get better performance at maximum range. Multiple in-situ tests were planned and carried out to test the above modems for their reliability and efficacy. II. EXPERIMENT SCENARIOS AND SETUP The field evaluation...

  20. Langasite Surface Acoustic Wave Sensors: Fabrication and Testing

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Peng; Greve, David W.; Oppenheim, Irving J.; Chin, Tao-Lun; Malone, Vanessa

    2012-02-01

    We report on the development of harsh-environment surface acoustic wave sensors for wired and wireless operation. Surface acoustic wave devices with an interdigitated transducer emitter and multiple reflectors were fabricated on langasite substrates. Both wired and wireless temperature sensing was demonstrated using radar-mode (pulse) detection. Temperature resolution of better than ±0.5°C was achieved between 200°C and 600°C. Oxygen sensing was achieved by depositing a layer of ZnO on the propagation path. Although the ZnO layer caused additional attenuation of the surface wave, oxygen sensing was accomplished at temperatures up to 700°C. The results indicate that langasite SAW devices are a potential solution for harsh-environment gas and temperature sensing.

  1. The experimental setup of the Interaction in Crystals for Emission of RADiation collaboration at Mainzer Mikrotron: Design, commissioning, and tests

    Energy Technology Data Exchange (ETDEWEB)

    Lietti, D., E-mail: Daniela.Lietti@cern.ch [Università degli Studi dell’Insubria, Via Valleggio 11, 22100 Como (Italy); Backe, H.; Lauth, W. [Institut für Kernphysik der Universität Mainz, D-55099 Mainz (Germany); Bagli, E.; Bandiera, L.; Germogli, G.; Guidi, V.; Mazzolari, A. [Università degli Studi di Ferrara, Via Saragat 1, 44100 Ferrara (Italy); INFN Sezione di Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Berra, A.; Prest, M. [Università degli Studi dell’Insubria, Via Valleggio 11, 22100 Como (Italy); INFN Sezione di Milano Bicocca, Piazza della Scienza 3, 20126 Milano (Italy); Carturan, S.; De Salvador, D. [Università degli Studi di Padova, Via Marzolo 8, 35131 Padova (Italy); INFN Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Legnaro (Italy); Vallazza, E. [INFN Sezione di Trieste, Via Valerio 2, 34127 Trieste (Italy)

    2015-04-15

    Silicon/germanium flat/bent crystals are thin devices able to efficiently deflect charged particle GeV-energy beams up to a few hundreds of μrad; moreover, high intensity photons can be efficiently produced in the so-called Multi-Volume Reflection (MVR) and Multiple Volume Reflections in One Crystal (MVROC) conditions. In the last years, the research interest in this field has moved to the dynamic studies of light negative leptons in the low energy range: the possibility to deflect negative particles and to produce high intensity γ sources via the coherent interactions with crystals in the sub-GeV energy range has been proved by the ICE-RAD (Interaction in Crystals for Emission of RADiation) Collaboration at the MAinzer MIkrotron (MAMI, Germany). This paper describes the setup used by the ICE-RAD experiment for the crystals characterization (both in terms of deflection and radiation emission properties): a high precision goniometer is used to align the crystals with the incoming beam, while a silicon based profilometer and an inorganic scintillator reconstruct, respectively, the particle position and the photon spectra after the samples. The crystals manufacturing process and their characterization, the silicon profilometer commissioning at the CERN PS T9 beamline, and the commissioning of the whole setup installed at MAMI are presented.

  2. Design, construction, activation, and operation of a high intensity acoustic test chamber

    Science.gov (United States)

    Kamel, L. T.

    1986-01-01

    The design philosophy, construction, integration, and activation of the high intensity acoustic test chamber for production acceptance testing of satellites are discussed. The 32,000 cubic-foot acoustic test cell consists of a steel reinforced concrete chamber with six electropneumatic noise generators. One of the innovative features of the chamber is a unique quarter horn assembly that acoustically couples the noise generators to the chamber. Design concepts, model testing, and evaluation results are presented. Considerations such as nitrogen versus compressed air source, digital closed loop spectrum control versus manual equalizers, and microprocessor based interlock systems are included. Construction difficulties, anomalies encountered, and their resolution are also discussed. Results of the readiness testing are highlighted.

  3. Solar array test set-up proposed by CNES in the frame of European standardization: Prevention of secondary arcing induced by electrostatic discharge

    OpenAIRE

    Payan, Denis; Schwander, Denis

    2005-01-01

    The validation of new solar cell for geostationary satellite application sets the problem of arcing between solar cells triggered by electrostatic discharges (ESD(sup 1)). The main difficulty of a ground test is to properly simulate the transient behavior of one string from the first microsecond of an electrostatic discharge and to take into account all the energy stored on a panel that would be released during hundreds of microseconds. The test set-up to use, with all the physical data we ne...

  4. The experimental determination of atmospheric absorption from aircraft acoustic flight tests

    Science.gov (United States)

    Miller, R. L.; Oncley, P. B.

    1971-01-01

    A method for determining atmospheric absorption coefficients from acoustic flight test data is presented. Measurements from five series of acoustic flight tests were included in the study. The number of individual flights totaled 24: six Boeing 707 flights performed in May 1969 in connection with the turbofan nacelle modification program, eight flights from Boeing tests conducted during the same period, and 10 flights of the Boeing 747 airplane. The effects of errors in acoustic, meteorological, and aircraft performance and position measurements are discussed. Tabular data of the estimated sample variance of the data for each test are given for source directivity angles from 75 deg to 120 deg and each 1/3-octave frequency band. Graphic comparisons are made of absorption coefficients derived from ARP 866, using atmospheric profile data, with absorption coefficients determined by the experimental method described in the report.

  5. Uniaxial compression CT and acoustic emission test on the coal crack propagation destruction process

    Institute of Scientific and Technical Information of China (English)

    Jing-hong LIU; Yao-dong JIANG; Yi-xin ZHAO; Jie ZHU

    2013-01-01

    Acoustic emission test and CT scanning are important techniques in the study of coal crack propagation.A uniaxial compression test was performed on coal samples by integrating CT and acoustic emission.The test comparison analyzes the acoustic emission load and CT images for an effective observation on the entire process,from crack propagation to the samples' destruction.The box dimension of the coal samples' acoustic emission series and the CT images were obtained through calculations by using the authors' own program.The results show that the fractal dimension of both the acoustic emission energy and CT image increase rapidly,indicating coal and rock mass has entered a dangerous condition.Hence,measures should be taken to unload the pressure of the coal and rock mass.The test results provide intuitive observation data for the coal meso-damage model.The test contributes to in-depth studies of coal or rock crack propagation mechanisms and provides a theoretical basis for rock burst mechanism.

  6. Monitoring and Analysis of In-Pile Phenomena in Advanced Test Reactor using Acoustic Telemetry

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Vivek [Idaho National Lab. (INL), Idaho Falls, ID (United States). Dept. of Human Factors, Controls, and Statistics; Smith, James A. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Dept. of Fuel Performance and Design; Jewell, James Keith [Idaho National Lab. (INL), Idaho Falls, ID (United States). Dept. of Fuel Performance and Design

    2015-02-01

    The interior of a nuclear reactor presents a particularly harsh and challenging environment for both sensors and telemetry due to high temperatures and high fluxes of energetic and ionizing particles among the radioactive decay products. A number of research programs are developing acoustic-based sensing approach to take advantage of the acoustic transmission properties of reactor cores. Idaho National Laboratory has installed vibroacoustic receivers on and around the Advanced Test Reactor (ATR) containment vessel to take advantage of acoustically telemetered sensors such as thermoacoustic (TAC) transducers. The installation represents the first step in developing an acoustic telemetry infrastructure. This paper presents the theory of TAC, application of installed vibroacoustic receivers in monitoring the in-pile phenomena inside the ATR, and preliminary data processing results.

  7. Aerodynamic and Acoustic Flight Test Results for the Stratospheric Observatory for Infrared Astronomy

    Science.gov (United States)

    Cumming, Stephen B.; Cliatt, Larry James; Frederick, Michael A.; Smith, Mark S.

    2013-01-01

    As part of the Stratospheric Observatory for Infrared Astronomy (SOFIA) program, a 747SP airplane was modified to carry a 2.5 meter telescope in the aft section of the fuselage. The resulting airborne observatory allows for observations above 99 percent of the water vapor in the atmosphere. The open cavity created by the modifications had the potential to significantly affect the airplane in the areas of aerodynamics and acoustics. Several series of flight tests were conducted to clear the airplanes operating envelope for astronomical observations, planned to be performed between the altitudes of 39,000 feet and 45,000 feet. The flight tests were successfully completed. Cavity acoustics were below design limits, and the overall acoustic characteristics of the cavity were better than expected. The modification did have some effects on the stability and control of the airplane, but these effects were not significant. Airplane air data systems were not affected by the modifications. This paper describes the methods used to examine the aerodynamics and acoustic data from the flight tests and provides a discussion of the flight test results in the areas of cavity acoustics, stability and control, and air data.

  8. Aerodynamic and Acoustic Flight Test Results and Results for the Stratospheric Observatory for Infrared Astronomy

    Science.gov (United States)

    Cumming, Stephen B.; Smith, Mark S.; Cliatt, Larry J.; Frederick, Michael A.

    2014-01-01

    As part of the Stratospheric Observatory for Infrared Astronomy program, a 747SP airplane was modified to carry a 2.5-m telescope in the aft section of the fuselage. The resulting airborne observatory allows for observations above 99 percent of the water vapor in the atmosphere. The open cavity created by the modifications had the potential to significantly affect the airplane in the areas of aerodynamics and acoustics. Several series of flight tests were conducted to clear the operating envelope of the airplane for astronomical observations, planned to be performed between the altitudes of 35,000 ft and 45,000 ft. The flight tests were successfully completed. Cavity acoustics were below design limits, and the overall acoustic characteristics of the cavity were better than expected. The modification did have some effects on the stability and control of the airplane, but these effects were not significant. Airplane air data systems were not affected by the modifications. This paper describes the methods used to examine the aerodynamics and acoustic data from the flight tests and provides a discussion of the flight-test results in the areas of cavity acoustics, stability and control, and air data.

  9. Characterization of acoustic lenses with the Foucault test by confocal laser scanning microscopy

    Science.gov (United States)

    Ahmed Mohamed, E. T.; Abdelrahman, A.; Pluta, M.; Grill, W.

    2010-03-01

    In this work, the Foucault knife-edge test, which has traditionally been known as the classic test for optical imaging devices, is used to characterize an acoustic lens for operation at 1.2 GHz. A confocal laser scanning microscope (CLSM) was used as the illumination and detection device utilizing its pinhole instead of the classical knife edge that is normally employed in the Foucault test. Information about the geometrical characteristics, such as the half opening angle of the acoustic lens, were determined as well as the quality of the calotte of the lens used for focusing. The smallest focal spot size that could be achieved with the examined lens employed as a spherical reflector was found to be about 1 μm. By comparison to the idealized resolution a degradation of about a factor of 2 can be deduced. This limits the actual quality of the acoustic focus.

  10. Irregular Liesegang-type patterns in gas phase revisited. I. Experimental setup, data processing, and test of the spacing law.

    Science.gov (United States)

    Torres-Guzmán, José C; Buhse, Thomas; de la Calleja, Elsa María; González-Espinoza, Alfredo; Martínez-Mekler, Gustavo; Montoya-Nava, Fernando; Ramírez-Álvarez, Elizeth; Rivera-Islas, Marco; Rodríguez-Álvarez, Aurora; Müller, Markus F

    2016-05-07

    Since the early work on Liesegang rings in gels, they have been a reference point for the study of pattern formation in chemical physics. Here we present a variant of the Liesegang experiment in gas phase, where ammonia and hydrochloric acid react within a glass tube producing a precipitate, which deposits along the tube wall producing a spatial pattern. With this apparently simple experiment a wide range of rich phenomenon can be observed due to the presence of convective flows and irregular dynamics reminiscent of turbulent behavior, for which precise measurements are scarce. In this first part of our work, we describe in detail the experimental setup, the method of data acquisition, the image processing, and the procedure used to obtain an intensity profile, which is representative of the amount of precipitate deposited at the tube walls. Special attention is devoted to the techniques rendering a data series reliable for statistical studies and model building, which may contribute to a characterization and understanding of the pattern formation phenomenon under consideration. As a first step in this direction, based on our data, we are able to show that the observed band pattern follows, with slight deviations, the spacing law encountered in common Liesegang rings, despite that the experimental conditions are very different. A further statistical correlation analysis of the data constitutes Paper II of this research.

  11. Initial Evaluation of Acoustic Emission SHM of PRSEUS Multi-bay Box Tests

    Science.gov (United States)

    Horne, Michael R.; Madaras, Eric I.

    2016-01-01

    A series of tests of the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) HWB Multi-Bay Test Article were conducted during the second quarter of 2015 at NASA Langley Research Center (LaRC) in the Combined Loads Test facility (COLTS). This report documents the Acoustic Emission (AE) data collected during those tests along with an initial analysis of the data. A more detailed analysis will be presented in future publications.

  12. Design and construction of a reverberation chamber for high-intensity acoustic testing.

    Science.gov (United States)

    Slusser, R. A.

    1973-01-01

    A high-intensity acoustic test facility was constructed at the Jet Propulsion Laboratory (JPL) to support the Mariner Mars 1971 project. For ease of construction, the reverberation chamber itself is rectangular, which resulted in very little sacrifice in acoustic performance. Levels as high as 156 dB can be achieved with the chamber empty and test levels of 150 dB have been used with a Mariner Mars spacecraft model (full size) in the chamber. Levels as high as this must be generated using electropneumatic transducers, which modulate gaseous nitrogen to this facility.

  13. Acoustic and thermal testing of the Titan/Centaur upper stage

    Science.gov (United States)

    Gehringer, Mark; Gibson, Chris; Janes, Ron

    1992-01-01

    A new version of the Centaur high-energy upper stage is being produced by General Dynamics for the USAF/Martin Marietta Titan launch vehicle. The Titan/Centaur upper stage is subject to consecutive acoustic and thermal testing in General Dynamics' Acoustic and Thermal Test Facility (ATTF). All data is acquired and processed digitally using the high-speed data acquisition system located in the ATTF. Processed data from over 250 sensors measuring acceleration, temperature, and sound pressure level is made available to the test team in minutes for use in making real-time test decisions. These tests represent the first consecutive large-scale environmental tests conducted on a complete, pressure stabilized, cryogenically tanked space launch vehicle. Some of the unique challenges involved in testing the Titan/Centaur and how these challenges were met using the ATTF are described.

  14. Acoustic and thermal testing of the Titan/Centaur upper stage

    Science.gov (United States)

    Gehringer, Mark; Gibson, Chris; Janes, Ron

    1992-11-01

    A new version of the Centaur high-energy upper stage is being produced by General Dynamics for the USAF/Martin Marietta Titan launch vehicle. The Titan/Centaur upper stage is subject to consecutive acoustic and thermal testing in General Dynamics' Acoustic and Thermal Test Facility (ATTF). All data is acquired and processed digitally using the high-speed data acquisition system located in the ATTF. Processed data from over 250 sensors measuring acceleration, temperature, and sound pressure level is made available to the test team in minutes for use in making real-time test decisions. These tests represent the first consecutive large-scale environmental tests conducted on a complete, pressure stabilized, cryogenically tanked space launch vehicle. Some of the unique challenges involved in testing the Titan/Centaur and how these challenges were met using the ATTF are described.

  15. Acoustic-Modal Testing of the Ares I Launch Abort System Attitude Control Motor Valve

    Science.gov (United States)

    Davis, R. Benjamin; Fischbach, Sean R.

    2010-01-01

    The Attitude Control Motor (ACM) is being developed for use in the Launch Abort System (LAS) of NASA's Ares I launch vehicle. The ACM consists of a small solid rocket motor and eight actuated pintle valves that directionally allocate.thrust_- 1t.has-been- predicted-that significant unsteady. pressure.fluctuations.will.exist. inside the-valves during operation. The dominant frequencies of these oscillations correspond to the lowest several acoustic natural frequencies of the individual valves. An acoustic finite element model of the fluid volume inside the valve has been critical to the prediction of these frequencies and their associated mode shapes. This work describes an effort to experimentally validate the acoustic finite model of the valve with an acoustic modal test. The modal test involved instrumenting a flight-like valve with six microphones and then exciting the enclosed air with a loudspeaker. The loudspeaker was configured to deliver broadband noise at relatively high sound pressure levels. The aquired microphone signals were post-processed and compared to results generated from the acoustic finite element model. Initial comparisons between the test data and the model results revealed that additional model refinement was necessary. Specifically, the model was updated to implement a complex impedance boundary condition at the entrance to the valve supply tube. This boundary condition models the frequency-dependent impedance that an acoustic wave will encounter as it reaches the end of the supply tube. Upon invoking this boundary condition, significantly improved agreement between the test data and the model was realized.

  16. Testing Time and Frequency Fiber-Optic Link Transfer by Hardware Emulation of Acoustic-Band Optical Noise

    Directory of Open Access Journals (Sweden)

    Lipiński Marcin

    2016-06-01

    Full Text Available The low-frequency optical-signal phase noise induced by mechanical vibration of the base occurs in field-deployed fibers. Typical telecommunication data transfer is insensitive to this type of noise but the phenomenon may influence links dedicated to precise Time and Frequency (T&F fiber-optic transfer that exploit the idea of stabilization of phase or propagation delay of the link. To measure effectiveness of suppression of acoustic noise in such a link, a dedicated measurement setup is necessary. The setup should enable to introduce a low-frequency phase corruption to the optical signal in a controllable way. In the paper, a concept of a setup in which the mechanically induced acoustic-band optical signal phase corruption is described and its own features and measured parameters are presented. Next, the experimental measurement results of the T&F transfer TFTS-2 system’s immunity as a function of the fibre-optic length vs. the acoustic-band noise are presented. Then, the dependency of the system immunity on the location of a noise source along the link is also pointed out.

  17. Development of a wind energy converter and investigation of its operational function. Part 4: Test setup and results of measurement

    Science.gov (United States)

    Armbrust, S.; Molly, J. P.

    1982-12-01

    Measurements made during test operations at the MODA.10 plant as well as at a 25 years old 6 kW wind energy converter are presented. The test arrangements, measurement results of both wind energy converters, and the experience gained are described.

  18. Validation of a Micrometric remotely controlled pre-alignment system for the CLIC Linear Collider using a test setup (Mock-Up) with 5 degrees of freedom

    CERN Document Server

    Mainaud Durand, H; Griffet, S; Kemppinen, J; Leuxe, R; Sosin, M

    2011-01-01

    The CLIC main beam quadrupoles need to be prealigned within 17 um rms with respect to a straight reference line along a sliding window of 200 m. A readjustment system based on eccentric cam movers, which will provide stiffness to the support assembly, is being studied. The cam movers were qualified on a 1 degree of freedom (DOF) test setup, where a repeatability of adjustment below 1um was measured along their whole range. This paper presents the 5 DOF mock-up, built for the validation of the eccentric cam movers, as well as the first results of tests carried out: resolution of displacement along the whole range, measurements of the support eigenfrequencies.

  19. Finalizing the CCSDS Space-Data Link Layer Security Protocol: Setup and Execution of the Interoperability Testing

    Science.gov (United States)

    Fischer, Daniel; Aguilar-Sanchez, Ignacio; Saba, Bruno; Moury, Gilles; Biggerstaff, Craig; Bailey, Brandon; Weiss, Howard; Pilgram, Martin; Richter, Dorothea

    2015-01-01

    The protection of data transmitted over the space-link is an issue of growing importance also for civilian space missions. Through the Consultative Committee for Space Data Systems (CCSDS), space agencies have reacted to this need by specifying the Space Data-Link Layer Security (SDLS) protocol which provides confidentiality and integrity services for the CCSDS Telemetry (TM), Telecommand (TC) and Advanced Orbiting Services (AOS) space data-link protocols. This paper describes the approach of the CCSDS SDLS working group to specify and execute the necessary interoperability tests. It first details the individual SDLS implementations that have been produced by ESA, NASA, and CNES and then the overall architecture that allows the interoperability tests between them. The paper reports on the results of the interoperability tests and identifies relevant aspects for the evolution of the test environment.

  20. Thick Films acoustic sensors devoted to MTR environment measurements. Thick Films acoustic sensors devoted to Material Testing Reactor environment measurements

    Energy Technology Data Exchange (ETDEWEB)

    Very, F.; Rosenkrantz, E.; Combette, P.; Ferrandis, J.Y. [University Montpellier, IES, UMR 5214, F-34000, Montpellier (France); CNRS, IES, UMR 5214, F-34000, Montpellier (France); Fourmentel, D.; Destouches, C.; Villard, J.F. [CEA, DEN, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St Paul lez Durance (France)

    2015-07-01

    The development of advanced instrumentation for in-pile experiments in Material Testing Reactor constitutes a main goal for the improvement of the nuclear fuel behavior knowledge. An acoustic method for fission gas release detection was tested with success during a first experiment called REMORA 3 in 2010 and 2011, and the results were used to differentiate helium and fission gas release kinetics under transient operating conditions. This experiment was lead at OSIRIS reactor (CEA Saclay, France). The maximal temperature on the sensor during the irradiation was about 150 deg. C. In this paper we present a thick film transducer produce by screen printing process. The screen printing of piezoelectric offers a wide range of possible applications for the development of acoustic sensors and piezoelectric structure for measurements in high temperature environment. We firstly produced a Lead Zirconate Titanate (PZT) based paste composed of Pz27 powder from Ferroperm, CF7575 glass, and organic solvent ESL 400. Likewise a Bismuth Titanate based paste synthesized in our laboratory was produced. With these inks we produced thick film up to 130 μm by screen printing process. Material properties characterizations of these thick-film resonators are essential for device design and applications. The piezoelectric coefficients d33 and pyro-electric P(T) coefficient are investigated. The highest P(T) and d33 are respectively 80 μC.m{sup -2}.K{sup -1} and 130 μC.N{sup -1} for the PZT transducer -which validates the fabrication process-. In view of the development of this transducer oriented for high temperature and irradiation environment, we investigated the electrical properties of the transducers for different ranges of frequencies and temperature - from 20 Hz up to 40 MHz between 30 and 400 deg. C. We highlight the evolution of the impedance response and piezoelectric parameters of screen printed piezoelectric structures on alumina. Shortly an irradiation will be realized in

  1. Test Set-Up for the Cooling of Heavy Magnets by Controlled Way Down to 77 K

    Science.gov (United States)

    Bajas, H.; Bajko, M.; Benda, V.; Bottura, L.; Bourgeois, G.; Charrondiere, M.; Chiuchiolo, A.; Ferracin, P.; Guinchard, M.; Garcia, J. E. Muñoz; Giloux, C.; Juchno, M.; Perez, J. C.; de Rijk, G.; Viret, P.; Ziemianski, D. T.

    In the scope of the High Field Magnets work package of the European FP7-EuCARD project, the structure of the future dipole magnet RMC and FRESCA2 has been tested at liquid nitrogen temperature replacing the actual Nb3Sn-based coils by aluminium dummy coils. Such test aims at measuring during the cooling the evolution of the mechanical stresses and the temperatures via compensated strain gauges and carbon-ceramic sensors placed at various locations on the structure (shell, rods, yokes, dummy coils). These measurements help assess the thermo-mechanical behaviour of the assembly for different applied pre-stresses and validate the finite element simulation of the magnet cooling before including the definitive brittle Nb3Sn coils. For this purpose, a specific cool-down/warm-up nitrogen test station has been built up at CERN in order to control the required maximum temperature gradient in the magnet during both cooling and warming. In this paper, we present in detail the test facility, the instrumentation along with the automatic process control system. An analytical approach computing the expected temperature evolution during a thermal cycle is introduced and the temperature measurements related to the magnets cooling down to 77 K and warm up to room temperature are presented.

  2. Setup planning for machining

    CERN Document Server

    Hazarika, Manjuri

    2015-01-01

    Professionals as well as researchers can benefit from this comprehensive introduction into the topic of setup planning, which reflects the latest state of research and gives hands-on examples. Starting with a brief but thorough introduction, this book explains the significance of setup planning in process planning and includes a reflection on its external constraints. Step-by-step the different phases of setup planning are outlined and traditional as well as modern approaches, such as fuzzy logic based setup planning, on the solution of setup planning problems are presented. Three detailed examples of applications provide a clear and accessible insight into the up-to-date techniques and various approaches in setup planning.

  3. KLauS: an ASIC for silicon photomultiplier readout and its application in a setup for production testing of scintillating tiles

    CERN Document Server

    Briggl, K; Hagdorn, R; Harion, T; Schultz-Coulon, H.C; Shen, W

    2014-01-01

    signals from silicon photomultipliers. Developed as an analog front-end for future calorimeters with high granularity as pursued by the AHCAL concept in the CALICE collaboration, the ASIC is designed to measure the charge signal of the sensors in a large dynamic range and with low electronic noise contributions. In order to tune the operation voltage of each sensor individually, an 8-bit DAC to tune the voltage at the input terminal within a range of 2V is implemented. Using an integrated fast comparator with low jitter, the time information can be measured with subnanosecond resolution. The low power consumption of the ASIC can be further decreased using power gating techniques. Future versions of KLauS are under development and will incorporate an ADC with a resolution of up to 12-bits and blocks for digital data transmission. The chip is used in a setup for mass testing and characterization of scintillator tiles for the AHCAL ...

  4. Points in the set-up of tests for fMRI. Toward the delineation of language-competent areas in clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Takashima, Hisaharu; Ejima, Mitsuhiro; Takeyama, Mamoru; Yamaguchi, Masami; Sato, Yoshino [Tokyo Women' s Medical Coll. (Japan). Hospital

    2001-06-01

    This hospital has performed fMRI of language-competent areas of the brain to identify the language-dominant hemisphere and obtain the configuration of the focus in the language-dominant side of the brain. Until now, signals have been detected in only two of fifteen patients who were diagnosed by language tests of a last-syllable word chain. In the present experiment, we tried to have subjects select the type of test. The result was that changes in signals were detected in eight of ten patients. Although the set-up of tests for fMRI is said to hold significant value, clear-cut studies to back this up have rarely been seen. Because clinical medicine treats patients who have difficulty in communication or suffer from aphasia, it is important to take into consideration individual variations and to set up a test suitable for, or achievable by, these individuals. The present method enabled us to avoid failure in examination caused by unsuccessful tests. (author)

  5. Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ageron, M. [CPPM-Centre de Physique des Particules de Marseille, CNRS/IN2P3 et Universite de la Mediterranee, 163 Avenue de Luminy, Case 902, 13288 Marseille Cedex 9 (France); Aguilar, J.A. [IFIC-Instituto de Fisica Corpuscular, Edificios Investigacion de Paterna, CSIC-Universitat de Valencia, Apdo. de Correos 22085, 46071 Valencia (Spain); Albert, A. [GRPHE-Groupe de Recherche en Physique des Hautes Energies, Universite de Haute Alsace, 61 Rue Albert Camus, 68093 Mulhouse Cedex (France); Ameli, F. [Dipartimento di Fisica dell' Universita ' La Sapienza' e Sezione INFN, P.le Aldo Moro 2, 00185 Roma (Italy); Anghinolfi, M. [Dipartimento di Fisica dell' Universita e Sezione INFN, Via Dodecaneso 33, 16146 Genova (Italy); Anton, G. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany); Anvar, S.; Ardellier-Desages, F. [DSM/DAPNIA-Direction des Sciences de la Matiere, Laboratoire de Recherche sur les lois Fondamentales de l' Univers, CEA Saclay, 91191 Gif-sur-Yvette Cedex (France); Aslanides, E.; Aubert, J.-J. [CPPM-Centre de Physique des Particules de Marseille, CNRS/IN2P3 et Universite de la Mediterranee, 163 Avenue de Luminy, Case 902, 13288 Marseille Cedex 9 (France); Auer, R. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany); Barbarito, E. [Dipartimento Interateneo di Fisica e Sezione INFN, Via E. Orabona 4, 70126 Bari (Italy); Basa, S. [LAM-Laboratoire d' Astrophysique de Marseille, CNRS/INSU et Universite de Provence, Traverse du Siphon-Les Trois Lucs, BP 8, 13012 Marseille Cedex 12 (France); Battaglieri, M. [Dipartimento di Fisica dell' Universita e Sezione INFN, Via Dodecaneso 33, 16146 Genova (Italy); Bazzotti, M.; Becherini, Y. [Dipartimento di Fisica dell' Universita e Sezione INFN, Viale Berti Pichat 6/2, 40127 Bologna (Italy)] (and others)

    2007-11-01

    A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented.

  6. AiResearch QCGAT engine: Acoustic test results

    Science.gov (United States)

    Kisner, L. S.

    1980-01-01

    The noise levels of the quiet, general aviation turbofan (QCGAT) engine were measured in ground static noise tests. The static noise levels were found to be markedly lower than the demonstrably quiet AiResearch model TFE731 engine. The measured QCGAT noise levels were correlated with analytical noise source predictions to derive free-field component noise predictions. These component noise sources were used to predict the QCGAT flyover noise levels at FAR Part 36 conditions. The predicted flyover noise levels are about 10 decibels lower than the current quietest business jets.

  7. Acoustic detection and localization from a tethered aerostat during the NATO TG-53 test

    Science.gov (United States)

    Reiff, C.; Scanlon, M.; Noble, J.

    2006-05-01

    Acoustic sensors mounted to a tethered aerostat detect and localize transient signals from mortars, artillery, C-4, propane cannon, and small arms fire. Significant enhancements to soldier lethality and survivability can be gained when using the aerostat array to detect, localize, and cue an aerial imager to a weapon's launch site, or use the aerostat's instantaneous position and orientation to calculate a vector solution to the ground coordinates of the launch site for threat neutralization. The prototype aerostat-mounted array was tested at Yuma Proving Grounds (YPG) as part of the NATO TG-53 signature collection exercise. Acoustic wave form data was collected simultaneously with aerostat and ground-based sensor arrays for comparing wind noise, signal to noise related parameters, and atmospheric effects on propagation to an elevated array. A test description and summary of localization accuracy will be presented for various altitudes, ranges to target, and under differing meteorological conditions.

  8. Structural Dynamic Assessment of the GN2 Piping System for NASA's New and Powerful Reverberant Acoustic Test Facility

    Science.gov (United States)

    McNelis, Mark E.; Staab, Lucas D.; Akers, James C.; Hughes, WIlliam O.; Chang, Li, C.; Hozman, Aron D.; Henry, Michael W.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) has led the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC's Plum Brook Station in Sandusky, Ohio, USA from 2007-2011. SAIC-Benham has completed construction of a new reverberant acoustic test facility to support the future testing needs of NASA's space exploration program and commercial customers. The large Reverberant Acoustic Test Facility (RATF) is approximately 101,000 cu ft in volume and was designed to operate at a maximum empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world's known active reverberant acoustic test facilities. Initial checkout acoustic testing was performed on March 2011 by SAIC-Benham at test levels up to 161 dB OASPL. During testing, several branches of the gaseous nitrogen (GN2) piping system, which supply the fluid to the noise generating acoustic modulators, failed at their "t-junctions" connecting the 12 inch supply line to their respective 4 inch branch lines. The problem was initially detected when the oxygen sensors in the horn room indicated a lower than expected oxygen level from which was inferred GN2 leaks in the piping system. In subsequent follow up inspections, cracks were identified in the failed "t-junction" connections through non-destructive evaluation testing . Through structural dynamic modeling of the piping system, the root cause of the "t-junction" connection failures was determined. The structural dynamic assessment identified several possible corrective design improvements to the horn room piping system. The effectiveness of the chosen design repairs were subsequently evaluated in September 2011 during acoustic verification testing to 161 dB OASPL.

  9. Structural Dynamic Assessment of the GN2 Piping System for NASA's New and Powerful Reverberant Acoustic Test Facility

    Science.gov (United States)

    McNelis, Mark E.; Staab, Lucas D.; Akers, James C.; Hughes, William O.; Chang, Li C.; Hozman, Aron D.; Henry, Michael W.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) has led the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC's Plum Brook Station in Sandusky, Ohio, USA from 2007 to 2011. SAIC-Benham has completed construction of a new reverberant acoustic test facility to support the future testing needs of NASA's space exploration program and commercial customers. The large Reverberant Acoustic Test Facility (RATF) is approximately 101,000 cubic feet in volume and was designed to operate at a maximum empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world s known active reverberant acoustic test facilities. Initial checkout acoustic testing was performed on March 2011 by SAIC-Benham at test levels up to 161 dB OASPL. During testing, several branches of the gaseous nitrogen (GN2) piping system, which supply the fluid to the noise generating acoustic modulators, failed at their T-junctions connecting the 12 in. supply line to their respective 4 in. branch lines. The problem was initially detected when the oxygen sensors in the horn room indicated a lower than expected oxygen level from which was inferred GN2 leaks in the piping system. In subsequent follow up inspections, cracks were identified in the failed T-junction connections through non-destructive evaluation testing. Through structural dynamic modeling of the piping system, the root cause of the T-junction connection failures was determined. The structural dynamic assessment identified several possible corrective design improvements to the horn room piping system. The effectiveness of the chosen design repairs were subsequently evaluated in September 2011 during acoustic verification testing to 161 dB OASPL.

  10. Tests of a Compton imaging prototype in a monoenergetic 4.44 MeV photon field—a benchmark setup for prompt gamma-ray imaging devices

    Science.gov (United States)

    Golnik, C.; Bemmerer, D.; Enghardt, W.; Fiedler, F.; Hueso-González, F.; Pausch, G.; Römer, K.; Rohling, H.; Schöne, S.; Wagner, L.; Kormoll, T.

    2016-06-01

    The finite range of a proton beam in tissue opens new vistas for the delivery of a highly conformal dose distribution in radiotherapy. However, the actual particle range, and therefore the accurate dose deposition, is sensitive to the tissue composition in the proton path. Range uncertainties, resulting from limited knowledge of this tissue composition or positioning errors, are accounted for in the form of safety margins. Thus, the unverified particle range constrains the principle benefit of proton therapy. Detecting prompt γ-rays, a side product of proton-tissue interaction, aims at an on-line and non-invasive monitoring of the particle range, and therefore towards exploiting the potential of proton therapy. Compton imaging of the spatial prompt γ-ray emission is a promising measurement approach. Prompt γ-rays exhibit emission energies of several MeV. Hence, common radioactive sources cannot provide the energy range a prompt γ-ray imaging device must be designed for. In this work a benchmark measurement-setup for the production of a localized, monoenergetic 4.44 MeV γ-ray source is introduced. At the Tandetron accelerator at the HZDR, the proton-capture resonance reaction 15N(p,α γ4.439)12C is utilized. This reaction provides the same nuclear de-excitation (and γ-ray emission) occurrent as an intense prompt γ-ray line in proton therapy. The emission yield is quantitatively described. A two-stage Compton imaging device, dedicated for prompt γ-ray imaging, is tested at the setup exemplarily. Besides successful imaging tests, the detection efficiency of the prototype at 4.44 MeV is derived from the measured data. Combining this efficiency with the emission yield for prompt γ-rays, the number of valid Compton events, induced by γ-rays in the energy region around 4.44 MeV, is estimated for the prototype being implemented in a therapeutic treatment scenario. As a consequence, the detection efficiency turns out to be a key parameter for prompt

  11. Force Limiting Vibration Tests Evaluated from both Ground Acoustic Tests and FEM Simulations of a Flight Like Vehicle System Assembly

    Science.gov (United States)

    Smith, Andrew; LaVerde, Bruce; Waldon, James; Hunt, Ron

    2014-01-01

    Marshall Space Flight Center has conducted a series of ground acoustic tests with the dual goals of informing analytical judgment, and validating analytical methods when estimating vibroacoustic responses of launch vehicle subsystems. The process of repeatedly correlating finite element-simulated responses with test-measured responses has assisted in the development of best practices for modeling and post-processing. In recent work, force transducers were integrated to measure interface forces at the base of avionics box equipment. Other force data was indirectly measured using strain gauges. The combination of these direct and indirect force measurements has been used to support and illustrate the advantages of implementing the Force Limiting approach for equipment qualification tests. The comparison of force response from integrated system level tests to measurements at the same locations during component level vibration tests provides an excellent illustration. A second comparison of the measured response cases from the system level acoustic tests to finite element simulations has also produced some principles for assessing the suitability of Finite Element Models (FEMs) for making vibroacoustics estimates. The results indicate that when FEM models are employed to guide force limiting choices, they should include sufficient detail to represent the apparent mass of the system in the frequency range of interest.

  12. Acoustic Nondestructive Testing and Measurement of Tension for Steel Reinforcing Members: Part 2 - Field Testing

    Science.gov (United States)

    2014-09-01

    steel beam-and-girder designs, but a significant problem is that the anchor tendons (i.e., rods) are inaccessible for expedient inspection and repair . A...embedded in concrete. Acoustic waves are nondestructive. They can travel long distances through engineered structures and can be used to thoroughly...complete post-tensioned anchorage system includes tendons (bars/rods or strands), anchorage devices or bearing plates, ducts, end caps, grout tubes

  13. Measurement of impulse peak insertion loss from two acoustic test fixtures and four hearing protector conditions with an acoustic shock tube.

    Science.gov (United States)

    Murphy, William J; Fackler, Cameron J; Berger, Elliott H; Shaw, Peter B; Stergar, Mike

    2015-01-01

    Impulse peak insertion loss (IPIL) was studied with two acoustic test fixtures and four hearing protector conditions at the E-A-RCAL Laboratory. IPIL is the difference between the maximum estimated pressure for the open-ear condition and the maximum pressure measured when a hearing protector is placed on an acoustic test fixture (ATF). Two models of an ATF manufactured by the French-German Research Institute of Saint-Louis (ISL) were evaluated with high-level acoustic impulses created by an acoustic shock tube at levels of 134 decibels (dB), 150 dB, and 168 dB. The fixtures were identical except that the E-A-RCAL ISL fixture had ear canals that were 3 mm longer than the National Institute for Occupational Safety and Health (NIOSH) ISL fixture. Four hearing protection conditions were tested: Combat Arms earplug with the valve open, ETYPlugs ® earplug, TacticalPro headset, and a dual-protector ETYPlugs earplug with TacticalPro earmuff. The IPILs measured for the E-A-RCAL fixture were 1.4 dB greater than the National Institute for Occupational Safety and Health (NIOSH) ISL ATF. For the E-A-RCAL ISL ATF, the left ear IPIL was 2.0 dB greater than the right ear IPIL. For the NIOSH ATF, the right ear IPIL was 0.3 dB greater than the left ear IPIL.

  14. Measurement of impulse peak insertion loss from two acoustic test fixtures and four hearing protector conditions with an acoustic shock tube

    Directory of Open Access Journals (Sweden)

    William J Murphy

    2015-01-01

    Full Text Available Impulse peak insertion loss (IPIL was studied with two acoustic test fixtures and four hearing protector conditions at the E-A-RCAL Laboratory. IPIL is the difference between the maximum estimated pressure for the open-ear condition and the maximum pressure measured when a hearing protector is placed on an acoustic test fixture (ATF. Two models of an ATF manufactured by the French-German Research Institute of Saint-Louis (ISL were evaluated with high-level acoustic impulses created by an acoustic shock tube at levels of 134 decibels (dB, 150 dB, and 168 dB. The fixtures were identical except that the E-A-RCAL ISL fixture had ear canals that were 3 mm longer than the National Institute for Occupational Safety and Health (NIOSH ISL fixture. Four hearing protection conditions were tested: Combat Arms earplug with the valve open, ETYPlugs ® earplug, TacticalPro headset, and a dual-protector ETYPlugs earplug with TacticalPro earmuff. The IPILs measured for the E-A-RCAL fixture were 1.4 dB greater than the National Institute for Occupational Safety and Health (NIOSH ISL ATF. For the E-A-RCAL ISL ATF, the left ear IPIL was 2.0 dB greater than the right ear IPIL. For the NIOSH ATF, the right ear IPIL was 0.3 dB greater than the left ear IPIL.

  15. Cold test with a benchtop set-up for fluidized bed reactor using quartz sand to simulate gasification of coal cokes by concentrated solar radiation

    Science.gov (United States)

    Gokon, Nobuyuki; Tanabe, Tomoaki; Shimizu, Tadaaki; Kodama, Tatsuya

    2016-05-01

    The impacts of internal circulation of a mixture of coal-coke particles and quartz sand on the fluidization state in a fluidized bed reactor are investigated by a cold test with a benchtop set-up in order to design 10-30 kWth scale prototype windowed fluidized-bed reactor. Firstly, a basic relationship between pressure loss of inlet gas and gas velocity was experimentally examined using quartz sand with different particle sizes by a small-scale quartz tube with a distributor at ambient pressure and temperature. Based on the results, an appropriate particle range of quartz sand and layer height/layer diameter ratio (L/D ratio) was determined for a design of the fluidized bed reactor. Secondly, a windowed reactor mock-up was designed and fabricated for solar coke gasification using quartz sand as a bed material. The pressure loss between the inlet and outlet gases was examined, and descending cokes and sand particles on the sidewall of the reactor was observed in the reactor mock-up. The moving velocity and distance of descending particles/sands from the top to bottom of fluidized bed were measured by the visual observation of the colored tracer particles on outside wall of the reactor.

  16. A versatile elevated-pressure reactor combined with an ultrahigh vacuum surface setup for efficient testing of model and powder catalysts under clean gas-phase conditions

    Energy Technology Data Exchange (ETDEWEB)

    Morfin, Franck; Piccolo, Laurent [Institut de recherches sur la catalyse et l' environnement de Lyon (IRCELYON), UMR 5256 CNRS and Université Lyon 1, 2 avenue Albert Einstein, F-69626 Villeurbanne (France)

    2013-09-15

    A small-volume reaction cell for catalytic or photocatalytic testing of solid materials at pressures up to 1000 Torr has been coupled to a surface-science setup used for standard sample preparation and characterization under ultrahigh vacuum (UHV). The reactor and sample holder designs allow easy sample transfer from/to the UHV chamber, and investigation of both planar and small amounts of powder catalysts under the same conditions. The sample is heated with an infrared laser beam and its temperature is measured with a compact pyrometer. Combined in a regulation loop, this system ensures fast and accurate temperature control as well as clean heating. The reaction products are automatically sampled and analyzed by mass spectrometry and/or gas chromatography (GC). Unlike previous systems, our GC apparatus does not use a recirculation loop and allows working in clean conditions at pressures as low as 1 Torr while detecting partial pressures smaller than 10{sup −4} Torr. The efficiency and versatility of the reactor are demonstrated in the study of two catalytic systems: butadiene hydrogenation on Pd(100) and CO oxidation over an AuRh/TiO{sub 2} powder catalyst.

  17. Evaluation of corrosion damage of aluminum alloy using acoustic emission testing

    Institute of Scientific and Technical Information of China (English)

    GENG Rongsheng; FU Gangqiang

    2004-01-01

    Current studies are aiming at monitoring corrosion damage of aircraft main structures by using acoustic emission (AE) technique and at supplying useful data for determining calendar life of the aircraft. The characteristics of AE signals produced during accelerating corrosion process are described, and methods for evaluating corrosion damages and determining remaining life of main structures of aircraft using AE testing are outlined. Experimental results have shown that AE technique can detect corrosion damage of aluminum alloy much earlier than conventional non-destructive testing means, such as ultrasonic testing and eddy current testing. Relationship between corrosion damage and AE parameters was obtained through investigating corrosion damage extent and changes of AE signals during accelerating corrosion test, and showing that AE technique can be used to detect early corrosion, investigating corrosion developing trend, and in monitoring and evaluating corrosion damages.

  18. Test method of frequency response based on diamond surface acoustic wave devices

    Institute of Scientific and Technical Information of China (English)

    CHEN Xi-ming; YANG Bao-he; WU Xiao-guo; WU Yi-zhuo

    2011-01-01

    In order to reduce the noises affixed to the signals when testing high frequency devices, a single-port test mode (S11) is used to test frequency response of high frequency (GHz) and dual-port surface acoustic wave devices (SAWDs) in this paper.The feasibility of the test is proved by simulating the Fabry-Perot model. The frequency response of the high-frequency dual-port resonant-type diamond SAWD is measured by S11 and the dual-port test mode (S21), respectively. The results show that the quality factor of the device is 51.29 and the 3 dB bandwidth is 27.8 MHz by S11 -mode measurement, which is better than the S21 mode, and is consistent with the frequency response curve by simulation.

  19. Comparison of Modal Analysis Methods Applied to a Vibro-Acoustic Test Article

    Science.gov (United States)

    Pritchard, Jocelyn; Pappa, Richard; Buehrle, Ralph; Grosveld, Ferdinand

    2001-01-01

    Modal testing of a vibro-acoustic test article referred to as the Aluminum Testbed Cylinder (ATC) has provided frequency response data for the development of validated numerical models of complex structures for interior noise prediction and control. The ATC is an all aluminum, ring and stringer stiffened cylinder, 12 feet in length and 4 feet in diameter. The cylinder was designed to represent typical aircraft construction. Modal tests were conducted for several different configurations of the cylinder assembly under ambient and pressurized conditions. The purpose of this paper is to present results from dynamic testing of different ATC configurations using two modal analysis software methods: Eigensystem Realization Algorithm (ERA) and MTS IDEAS Polyreference method. The paper compares results from the two analysis methods as well as the results from various test configurations. The effects of pressurization on the modal characteristics are discussed.

  20. Mechanical design and vibro-acoustic testing of ultrathin carbon foils for a spacecraft instrument

    Energy Technology Data Exchange (ETDEWEB)

    Bernardin, John D [Los Alamos National Laboratory; Baca, Allen G [SNL

    2009-01-01

    IBEX-Hi is an electrostatic analyzer spacecraft instrument designed to measure the energy and flux distribution of energetic neutral atoms (ENAs) emanating from the interaction zone between the Earth's solar system and the Milky Way galaxy. A key element to this electro-optic instrument is an array of fourteen carbon foils that are used to ionize the ENAs. The foils are comprised of an ultrathin (50-100 {angstrom} thick) layer of carbon suspended across the surface of an electroformed Nickel wire screen, which in turn is held taught by a metal frame holder. The electro formed orthogonal screen has square wire elements, 12.7 {micro}m thick, with a pitch of 131.1 wires/cm. Each foil holder has an open aperture approximately 5 cm by 2.5 cm. Designing and implementing foil holders with such a large surface area has not been attempted for spaceflight in the past and has proven to be extremely challenging. The delicate carbon foils are subject to fatigue failure from the large acoustic and vibration loads that they will be exposed to during launch of the spacecraft. This paper describes the evolution of the foil holder design from previous space instrument applications to a flight-like IBEX-Hi prototype. Vibro-acoustic qualification tests of the IBEX-Hi prototype instrument and the resulting failure of several foils are summarized. This is followed by a discussion of iterative foil holder design modifications and laser vibrometer modal testing to support future fatigue failure analyses, along with additional acoustic testing of the IBEX-Hi prototype instrument. The results of these design and testing activities are merged and the resulting flight-like foil holder assembly is proposed.

  1. SEALDH-II-An Autonomous, Holistically Controlled, First Principles TDLAS Hygrometer for Field and Airborne Applications: Design-Setup-Accuracy/Stability Stress Test.

    Science.gov (United States)

    Buchholz, Bernhard; Kallweit, Sören; Ebert, Volker

    2016-12-30

    Instrument operation in harsh environments often significantly impacts the trust level of measurement data. While commercial instrument manufacturers clearly define the deployment conditions to achieve trustworthy data in typical standard applications, it is frequently unavoidable in scientific field applications to operate instruments outside these commercial standard application specifications. Scientific instrumentation, however, is employing cutting-edge technology and often highly optimized but also lacks long-term field tests to assess the field vs. laboratory performance. Recently, we developed the Selective Extractive Laser Diode Hygrometer (SEALDH-II), which addresses field and especially airborne applications as well as metrological laboratory validations. SEALDH-II targets reducing deviations between airborne hygrometers (currently up to 20% between the most advanced hygrometers) with a new holistic, internal control and validation concept, which guarantees the transfer of the laboratory performance into a field scenario by capturing more than 80 instrument internal "housekeeping" data to nearly perfectly control SEALDH-II's health status. SEALDH-II uses a calibration-free, first principles based, direct Tuneable Diode Laser Absorption Spectroscopy (dTDLAS) approach, to cover the entire atmospheric humidity measurement range from about 3 to 40,000 ppmv with a calculated maximum uncertainty of 4.3% ± 3 ppmv. This is achieved not only by innovations in internal instrument monitoring and design, but also by active control algorithms such as a high resolution spectral stabilization. This paper describes the setup, working principles, and instrument stabilization, as well as its precision validation and long-term stress tests in an environmental chamber over an environmental temperature and humidity range of ΔT = 50 K and ΔRH = 80% RH, respectively.

  2. Acoustic Testing for Melon Fruit Ripeness Evaluation during Different Stages of Ripening

    Directory of Open Access Journals (Sweden)

    Farhad Khoshnam

    2016-05-01

    Full Text Available Non-destructive impulse response technique was tested on two melon varieties (‘Zard-Eyvanekey’ and ‘Sousky-Sabz’ in five different stages of ripening. Resonance frequency and sound pressure level (SPL from the impulse response were compared with mass, elastic modulus, soluble solids contents (TSS and sensory evaluation. Among acoustic and destructive parameters, resonance frequency is an indicator to distinguish of different maturity stage of the melon in both varieties. The sound pressure level (SPL was not a reliable parameter to evaluate melon ripeness. It was established that the impulse response technique is useful to decide fruit maturity stage and appropriate harvest time.

  3. [Measurement of evoked acoustic otoemissions: an early screening test of neonatal deafness].

    Science.gov (United States)

    Morgon, Alain

    2002-01-01

    Every child born with deafness displays a pathological language development. An early and specific approach is mandatory, hence requiring an universal hearing screening. Available evidence indicate that performing acoustic otoemissions prior to six months of age is the most reliable method. The recording of the AOE is performed successfully from the 30th week of conceptual age. To obtain AOE in the newborn, one needs to wait until the 3rd day post delivery in 98% of cases. The reliability of the test, the socio-economical cost, the consequences of the screening and the role of the family have to be discussed.

  4. Testing the neutrality of matter by acoustic means in a spherical resonator

    CERN Document Server

    Bressi, G; Della Valle, F; Galeazzi, G; Ruoso, G; Sartori, G

    2011-01-01

    New measurements to test the neutrality of matter by acoustic means are reported. The apparatus is based on a spherical capacitor filled with gaseous SF$_6$ excited by an oscillating electric field. The apparatus has been calibrated measuring the electric polarizability. Assuming charge conservation in the $\\beta$ decay of the neutron, the experiment gives a limit of $\\epsilon_\\text{p-e}\\lesssim1\\cdot10^{-21}$ for the electron-proton charge difference, the same limit holding for the charge of the neutron. Previous measurements are critically reviewed and found incorrect: the present result is the best limit obtained with this technique.

  5. Integration of Acoustic Neutrino Detection Methods into ANTARES

    CERN Document Server

    Graf, K; Hoessl, J; Kappes, A; Katz, U F; Lahmann, R; Naumann, C; Salomon, K

    2007-01-01

    The ANTARES Neutrino Telescope is a water Cherenkov detector currently under construction in the Mediterranean Sea. It is also designed to serve as a platform for investigations of the deep-sea environment. In this context, the ANTARES group at the University of Erlangen will integrate acoustic sensors within the infrastructure of the experiment. With this dedicated setup, tests of acoustic particle detection methods and deep-sea acoustic background studies shall be performed. The aim of this project is to evaluate the feasibility of a future acoustic neutrino telescope in the deep sea operating in the ultra-high energy regime. In these proceedings, the implementation of the project is described in the context of the premises and challenges set by the physics of acoustic particle detection and the integration into an existing infrastructure.

  6. Testing the effectiveness of an acoustic deterrent for gray whales along the Oregon coast

    Energy Technology Data Exchange (ETDEWEB)

    Lagerquist, Barbara [Oregon State University Marine Mammal Institute; Winsor, Martha [Oregon State University Marine Mammal Institute; Mate, Bruce [Oregon State University Marine Mammal Institute

    2012-12-31

    This study was conducted to determine whether a low-powered sound source could be effective at deterring gray whales from areas that may prove harmful to them. With increased interest in the development of marine renewal energy along the Oregon coast the concern that such development may pose a collision or entanglement risk for gray whales. A successful acoustic deterrent could act as a mitigation tool to prevent harm to whales from such risks. In this study, an acoustic device was moored on the seafloor in the pathway of migrating gray whales off Yaquina Head on the central Oregon coast. Shore-based observers tracked whales with a theodolite (surveyor’s tool) to accurately locate whales as they passed the headland. Individual locations of different whales/whale groups as well as tracklines of the same whale/whale groups were obtained and compared between times with the acoustic device was transmitting and when it was off. Observations were conducted on 51 d between January 1 and April 15, 2012. A total of 143 individual whale locations were collected for a total of 243 whales, as well as 57 tracklines for a total of 142 whales. Inclement weather and equipment problems resulted in very small sample sizes, especially during experimental periods, when the device was transmitting. Because of this, the results of this study were inconclusive. We feel that another season of field testing is warranted to successfully test the effectiveness of the deterrent, but recommend increasing the zone of influence to 3 km to ensure the collection of adequate sample sizes. Steps have been taken to acquire the necessary federal research permit modification to authorize the increased zone of influence and to modify the acoustic device for the increased power. With these changes we are confident we will be able to determine whether the deterrent is effective at deflecting gray whales. A successful deterrent device may serve as a valuable mitigation tool to protect gray whales, and

  7. Measurement of Overall Performance Effectiveness in Setup Improvement

    Directory of Open Access Journals (Sweden)

    Shye-Nee Low

    2014-01-01

    Full Text Available This study aimed to improve the setup process of injection molding machines by using the developed setup improvement methodology. Overall performance effectiveness (OPE was used to evaluate the setup improvement. A case study was tested on the application of the developed setup improvement methodology. A 50.1% reduction in setup time was attained by the developed methodology, and significant time savings were achieved with minimum investment. Comparisons between before and after improvement implementation were conducted through OPE to verify the improvement. In terms of OPE, the setup performance in the case study considered an acceptable value of 60.45%. The setup process performance of the developed setup improvement methodology was judged in terms of effectiveness. Results therefore indicate that OPE measurement is an effective way to analyze the efficiency of a single setup process.

  8. Computational Fluid Dynamics Study on the Effects of RATO Timing on the Scale Model Acoustic Test

    Science.gov (United States)

    Nielsen, Tanner; Williams, B.; West, Jeff

    2015-01-01

    The Scale Model Acoustic Test (SMAT) is a 5% scale test of the Space Launch System (SLS), which is currently being designed at Marshall Space Flight Center (MSFC). The purpose of this test is to characterize and understand a variety of acoustic phenomena that occur during the early portions of lift off, one being the overpressure environment that develops shortly after booster ignition. The SLS lift off configuration consists of four RS-25 liquid thrusters on the core stage, with two solid boosters connected to each side. Past experience with scale model testing at MSFC (in ER42), has shown that there is a delay in the ignition of the Rocket Assisted Take Off (RATO) motor, which is used as the 5% scale analog of the solid boosters, after the signal to ignite is given. This delay can range from 0 to 16.5ms. While this small of a delay maybe insignificant in the case of the full scale SLS, it can significantly alter the data obtained during the SMAT due to the much smaller geometry. The speed of sound of the air and combustion gas constituents is not scaled, and therefore the SMAT pressure waves propagate at approximately the same speed as occurs during full scale. However, the SMAT geometry is much smaller allowing the pressure waves to move down the exhaust duct, through the trench, and impact the vehicle model much faster than occurs at full scale. To better understand the effect of the RATO timing simultaneity on the SMAT IOP test data, a computational fluid dynamics (CFD) analysis was performed using the Loci/CHEM CFD software program. Five different timing offsets, based on RATO ignition delay statistics, were simulated. A variety of results and comparisons will be given, assessing the overall effect of RATO timing simultaneity on the SMAT overpressure environment.

  9. AMADEUS-The acoustic neutrino detection test system of the ANTARES deep-sea neutrino telescope

    NARCIS (Netherlands)

    Aguilar, J. A.; Al Samarai, I.; Albert, A.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Jesus, A. C. Assis; Astraatmadja, T.; Aubert, J. -J.; Auer, R.; Barbarito, E.; Baret, B.; Basa, S.; Bazzotti, M.; Bertin, V.; Biagi, S.; Bigongiari, C.; Bou-Cabo, M.; Bouwhuis, M. C.; Brown, A.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Carloganu, C.; Carminati, G.; Carr, J.; Cassano, B.; Castorina, E.; Cavasinni, V.; Cecchini, S.; Ceres, A.; Charvis, Ph.; Chiarusi, T.; Sen, N. Chon; Circella, M.; Coniglione, R.; Costantini, H.; Cottini, N.; Coyle, P.; Curtil, C.; De Bonis, G.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Drouhin, D.; Eberl, T.; Emanuele, U.; Ernenwein, J. -P.; Escoffier, S.; Fehr, F.; Fiorello, C.; Flaminio, V.; Fritsch, U.; Fuda, J. -L.; Gay, P.; Giacomelli, G.; Gomez-Gonzalez, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Heijboer, A. J.; Heine, E.; Hello, Y.; Hernandez-Rey, J. J.; Herold, B.; Hoessl, J.; de Jong, M.; Kalantar-Nayestanaki, N.; Kalekin, O.; Kappes, A.; Katz, U.; Keller, P.; Kooijman, P.; Kopper, C.; Kouchneri, A.; Kretschmer, W.; Lahmann, R.; Lamare, P.; Lambard, G.; Larosa, G.; Laschinsky, H.; Le Provost, H.; Lefevre, D.; Lelaizant, G.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J. A.; Mazure, A.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Motz, H.; Naumann, C.; Neff, M.; Ostasch, R.; Palioselitis, D.; Pavalas, G. E.; Payre, P.; Petrovic, J.; Picot-Clemente, N.; Picq, C.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Radu, A.; Reed, C.; Riccobene, G.; Richardt, C.; Rujoiu, M.; Ruppi, M.; Russo, G. V.; Salesa, F.; Sapienza, P.; Schoeck, F.; Schuller, J. -P.; Shanidze, R.; Simeone, F.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Taiuti, M.; Tamburini, C.; Tasca, L.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wijnker, G.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zuniga, J.

    2011-01-01

    The AMADEUS (ANTARES Modules for the Acoustic Detection Under the Sea) system which is described in this article aims at the investigation of techniques for acoustic detection of neutrinos in the deep sea. It is integrated into the ANTARES neutrino telescope in the Mediterranean Sea. Its acoustic se

  10. 声振检测方法的发展%Evolution of the Acoustic Impact Testing Method

    Institute of Scientific and Technical Information of China (English)

    邬冠华; 林俊明; 任吉林; 周昌智

    2011-01-01

    依据激励方式的不同,分别从敲击检测和声阻检测方法两个方面对声振检测方法进行了介绍.敲击检测方法主要分整体振动检测法(或车轮敲击法)和局部振动检测法(或硬币敲击法),声阻检测法主要分机械阻抗法和局部共振检测法.声振检测方法尽管很早以前就已经出现了,但至今主要还停留在经验性的应用层面.对各种声振检测方法的基本原理及其发展作简要论述,希望起到抛砖引玉的作用,吸引业界关注该方法发展和应用的同仁共同来推进它的技术进步.%The acoustic impact testing method is presented with two different excitation methods: the tap testing method and the acoustic impedance testing method.The tap testing method includes the whole vibration testing (wheel-tap test) method and the local vibration testing method( coin-tap test), and the acoustic impedance method has the mechanical impedance method and the local resonance testing method.Though the acoustic impact testing method has a long history in testing activities, most concerns of this method are only restricted in its experiential applications.Here, the principals and their developments of several branches of the acoustic impact testing method are covered, with the main purpose to improve this old but effective method with the help of the people who concern its development and applications.

  11. Rock burst proneness prediction by acoustic emission test during rock deformation

    Institute of Scientific and Technical Information of China (English)

    张志镇; 高峰; 尚晓吉

    2014-01-01

    Rock burst is a severe disaster in mining and underground engineering, and it is important to predict the rock burst risk for minimizing the loss during the constructing process. The rock burst proneness was connected with the acoustic emission (AE) parameter in this work, which contributes to predicting the rock burst risk using AE technique. Primarily, a rock burst proneness index is proposed, and it just depends on the heterogeneous degree of rock material. Then, the quantificational formula between the value of rock burst proneness index and the accumulative AE counts in rock sample under uniaxial compression with axial strain increases is developed. Finally, three kinds of rock samples, i.e., granite, limestone and sandstone are tested about variation of the accumulative AE counts under uniaxial compression, and the test data are fitted well with the theoretic formula.

  12. Characterization of the Scale Model Acoustic Test Overpressure Environment using Computational Fluid Dynamics

    Science.gov (United States)

    Nielsen, Tanner; West, Jeff

    2015-01-01

    The Scale Model Acoustic Test (SMAT) is a 5% scale test of the Space Launch System (SLS), which is currently being designed at Marshall Space Flight Center (MSFC). The purpose of this test is to characterize and understand a variety of acoustic phenomena that occur during the early portions of lift off, one being the overpressure environment that develops shortly after booster ignition. The pressure waves that propagate from the mobile launcher (ML) exhaust hole are defined as the ignition overpressure (IOP), while the portion of the pressure waves that exit the duct or trench are the duct overpressure (DOP). Distinguishing the IOP and DOP in scale model test data has been difficult in past experiences and in early SMAT results, due to the effects of scaling the geometry. The speed of sound of the air and combustion gas constituents is not scaled, and therefore the SMAT pressure waves propagate at approximately the same speed as occurs in full scale. However, the SMAT geometry is twenty times smaller, allowing the pressure waves to move down the exhaust hole, through the trench and duct, and impact the vehicle model much faster than occurs at full scale. The DOP waves impact portions of the vehicle at the same time as the IOP waves, making it difficult to distinguish the different waves and fully understand the data. To better understand the SMAT data, a computational fluid dynamics (CFD) analysis was performed with a fictitious geometry that isolates the IOP and DOP. The upper and lower portions of the domain were segregated to accomplish the isolation in such a way that the flow physics were not significantly altered. The Loci/CHEM CFD software program was used to perform this analysis.

  13. Monitoring accelerated carbonation on standard Portland cement mortar by nonlinear resonance acoustic test

    Science.gov (United States)

    Eiras, J. N.; Kundu, T.; Popovics, J. S.; Monzó, J.; Borrachero, M. V.; Payá, J.

    2015-03-01

    Carbonation is an important deleterious process for concrete structures. Carbonation begins when carbon dioxide (CO2) present in the atmosphere reacts with portlandite producing calcium carbonate (CaCO3). In severe carbonation conditions, C-S-H gel is decomposed into silica gel (SiO2.nH2O) and CaCO3. As a result, concrete pore water pH decreases (usually below 10) and eventually steel reinforcing bars become unprotected from corrosion agents. Usually, the carbonation of the cementing matrix reduces the porosity, because CaCO3 crystals (calcite and vaterite) occupy more volume than portlandite. In this study, an accelerated carbonation-ageing process is conducted on Portland cement mortar samples with water to cement ratio of 0.5. The evolution of the carbonation process on mortar is monitored at different levels of ageing until the mortar is almost fully carbonated. A nondestructive technique based on nonlinear acoustic resonance is used to monitor the variation of the constitutive properties upon carbonation. At selected levels of ageing, the compressive strength is obtained. From fractured surfaces the depth of carbonation is determined with phenolphthalein solution. An image analysis of the fractured surfaces is used to quantify the depth of carbonation. The results from resonant acoustic tests revealed a progressive increase of stiffness and a decrease of material nonlinearity.

  14. Experimental validation of a boundary element solver for exterior acoustic radiation problems

    OpenAIRE

    Visser, Rene; Nilsson, A; Boden, H.

    2003-01-01

    The relation between harmonic structural vibrations and the corresponding acoustic radiation is given by the Helmholtz integral equation (HIE). To solve this integral equation a new solver (BEMSYS) based on the boundary element method (BEM) has been implemented. This numerical tool can be used for both sound radiation and nearfield acoustic source localization purposes. After validation of the solver with analytic solutions of simple test problems, a well-defined experimental setup has been d...

  15. A mechanical experimental setup to simulate vocal folds vibrations. Preliminary results

    CERN Document Server

    Ruty, Nicolas; Pelorson, Xavier; Lopez-Arteaga, Ines; Hirschberg, Avraham

    2005-01-01

    This paper contributes to the understanding of vocal folds oscillation during phonation. In order to test theoretical models of phonation, a new experimental set-up using a deformable vocal folds replica is presented. The replica is shown to be able to produce self sustained oscillations under controlled experimental conditions. Therefore different parameters, such as those related to elasticity, to acoustical coupling or to the subglottal pressure can be quantitatively studied. In this work we focused on the oscillation fundamental frequency and the upstream pressure in order to start (on-set threshold) either end (off-set threshold) oscillations in presence of a downstream acoustical resonator. As an example, it is shown how this data can be used in order to test the theoretical predictions of a simple one-mass model.

  16. Background studies for acoustic neutrino detection at the South Pole

    CERN Document Server

    Abbasi, R; Abu-Zayyad, T; Adams, J; Aguilar, J A; Ahlers, M; Andeen, K; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Bay, R; Alba, J L Bazo; Beattie, K; Beatty, J J; Bechet, S; Becker, J K; Becker, K -H; Benabderrahmane, M L; BenZvi, S; Berdrmann, J; Berghaus, P; Berley, D; Bernardini, E; Bertrand, D; Besson, D Z; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohm, C; Bose, D; Böser, S; Botner, O; Braun, J; Brown, A M; Buitink, S; Carson, M; Chirkin, D; Christy, B; Clem, J; Clevermann, F; Cohen, S; Colnard, C; Cowen, D F; D'Agostino, M V; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; Demirörs, L; Denger, T; Depaepe, O; Descamps, F; Desiati, P; de Vries-Uiterweerd, G; DeYoung, T; Diaz-Vélez, J C; Dierckxsens, M; Dreyer, J; Dumm, J P; Ehrlich, R; Eisch, J; Ellsworth, R W; Engdegård, O; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Foerster, M M; Fox, B D; Franckowiak, A; Franke, R; Gaisser, T K; Gallagher, J; Geisler, M; Gerhardt, L; Gladstone, L; Glüsenkamp, T; Goldschmidt, A; Goodman, J A; Grant, D; Griesel, T; Groß, A; Grullon, S; Gurtner, M; Ha, C; Hallgren, A; Halzen, F; Han, K; Hanson, K; Heinen, D; Helbing, K; Herquet, P; Hickford, S; Hill, G C; Hoffman, K D; Homeier, A; Hoshina, K; Hubert, D; Huelsnitz, W; Hülß, J -P; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobsen, J; Japaridze, G S; Johansson, H; Joseph, J M; Kampert, K -H; Kappes, A; Karg, T; Karle, A; Kelley, J L; Kenny, P; Kiryluk, J; Kislat, F; Klein, S R; Köhne, J -H; Kohnen, G; Kolanoski, H; Köpke, L; Kopper, S; Koskinen, D J; Kowalski, M; Kowarik, T; Krasberg, M; Krings, T; Kroll, G; Kuehn, K; Kuwabara, T; Labare, M; Lafebre, S; Laihem, K; Landsman, H; Larson, M J; Lauer, R; Lünemann, J; Madsen, J; Majumdar, P; Marotta, A; Maruyama, R; Mase, K; Matis, H S; Meagher, K; Merck, M; Mészáros, P; Meures, T; Middell, E; Milke, N; Miller, J; Montaruli, T; Morse, R; Movit, S M; Nahnhauer, R; Nam, J W; Naumann, U; Nießen, P; Nygren, D R; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Ono, M; Panknin, S; Paul, L; Heros, C Pérez de los; Petrovic, J; Piegsa, A; Pieloth, D; Porrata, R; Posselt, J; Price, P B; Prikockis, M; Przybylski, G T; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Rizzo, A; Rodrigues, J P; Roth, P; Rothmaier, F; Rott, C; Ruhe, T; Rutledge, D; Ruzybayev, B; Ryckbosch, D; Sander, H -G; Santander, M; Sarkar, S; Schatto, K; Schmidt, T; Schönwald, A; Schukraft, A; Schultes, A; Schulz, O; Schunck, M; Seckel, D; Semburg, B; Seo, S H; Sestayo, Y; Seunarine, S; Silvestri, A; Slipak, A; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stephens, G; Stezelberger, T; Stokstad, R G; Stössl, A; Stoyanov, S; Strahler, E A; Straszheim, T; Stür, M; Sullivan, G W; Swillens, Q; Taavola, H; Taboada, I; Tamburro, A; Tepe, A; Ter-Antonyan, S; Tilav, S; Toale, P A; Toscano, S; Tosi, D; Turčan, D; van Eijndhoven, N; Vandenbroucke, J; Van Overloop, A; van Santen, J; Vehring, M; Voge, M; Walck, C; Waldenmaier, T; Wallraff, M; Walter, M; Weaver, Ch; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wischnewski, R; Wissing, H; Wolf, M; Woschnagg, K; Xu, C; Xu, X W; Yodh, G; Yoshida, S; Zarzhitsky, P

    2011-01-01

    The detection of acoustic signals from ultra-high energy neutrino interactions is a promising method to measure the tiny flux of cosmogenic neutrinos expected on Earth. The energy threshold for this process depends strongly on the absolute noise level in the target material. The South Pole Acoustic Test Setup (SPATS), deployed in the upper part of four boreholes of the IceCube Neutrino Observatory, has monitored the noise in Antarctic ice at the geographic South Pole for more than two years down to 500 m depth. The noise is very stable and Gaussian distributed. Lacking an in-situ calibration up to now, laboratory measurements have been used to estimate the absolute noise level in the 10 to 50 kHz frequency range to be smaller than 20 mPa. Using a threshold trigger, sensors of the South Pole Acoustic Test Setup registered acoustic pulse-like events in the IceCube detector volume and its vicinity. Acoustic signals from refreezing IceCube holes and from anthropogenic sources have been used to localize acoustic e...

  17. Statistical Test of Distance-Duality Relation with Type Ia Supernovae and Baryon Acoustic Oscillations

    CERN Document Server

    Ma, Cong

    2016-01-01

    We use cosmological luminosity distance ($d_L$) from the JLA Type Ia supernovae compilation and angular-diameter distance ($d_A$) based on BOSS and WiggleZ baryon acoustic oscillation measurements to test the distance-duality relation $\\eta \\equiv d_L / [ (1 + z)^2 d_A ] = 1$. The $d_L$ measurements are matched to $d_A$ redshift by a statistically-motivated compression procedure. By means of Monte Carlo methods, non-trivial and correlated distributions of $\\eta$ can be explored in a straightforward manner without resorting to a particular evolution template $\\eta(z)$. Assuming Planck cosmological parameter uncertainty, we find 5% constraints in favor of $\\eta = 1$, consistent with the weaker 7--10% constraints obtained using WiggleZ data. These results stand in contrast to previous claims that $\\eta < 1$ has been found close to or above $1\\sigma$ level.

  18. Evaluation of Acoustic Emission NDE of Composite Crew Module Service Module/Alternate Launch Abort System (CCM SM/ALAS) Test Article Failure Tests

    Science.gov (United States)

    Horne, Michael R.; Madaras, Eric I.

    2010-01-01

    Failure tests of CCM SM/ALAS (Composite Crew Module Service Module / Alternate Launch Abort System) composite panels were conducted during July 10, 2008 and July 24, 2008 at Langley Research Center. This is a report of the analysis of the Acoustic Emission (AE) data collected during those tests.

  19. Test-bench system for a borehole azimuthal acoustic reflection imaging logging tool

    Science.gov (United States)

    Liu, Xianping; Ju, Xiaodong; Qiao, Wenxiao; Lu, Junqiang; Men, Baiyong; Liu, Dong

    2016-06-01

    The borehole azimuthal acoustic reflection imaging logging tool (BAAR) is a new generation of imaging logging tool, which is able to investigate stratums in a relatively larger range of space around the borehole. The BAAR is designed based on the idea of modularization with a very complex structure, so it has become urgent for us to develop a dedicated test-bench system to debug each module of the BAAR. With the help of a test-bench system introduced in this paper, test and calibration of BAAR can be easily achieved. The test-bench system is designed based on the client/server model. The hardware system mainly consists of a host computer, an embedded controlling board, a bus interface board, a data acquisition board and a telemetry communication board. The host computer serves as the human machine interface and processes the uploaded data. The software running on the host computer is designed based on VC++. The embedded controlling board uses Advanced Reduced Instruction Set Machines 7 (ARM7) as the micro controller and communicates with the host computer via Ethernet. The software for the embedded controlling board is developed based on the operating system uClinux. The bus interface board, data acquisition board and telemetry communication board are designed based on a field programmable gate array (FPGA) and provide test interfaces for the logging tool. To examine the feasibility of the test-bench system, it was set up to perform a test on BAAR. By analyzing the test results, an unqualified channel of the electronic receiving cabin was discovered. It is suggested that the test-bench system can be used to quickly determine the working condition of sub modules of BAAR and it is of great significance in improving production efficiency and accelerating industrial production of the logging tool.

  20. Resolution of Forces and Strain Measurements from an Acoustic Ground Test

    Science.gov (United States)

    Smith, Andrew M.; LaVerde, Bruce T.; Hunt, Ronald; Waldon, James M.

    2013-01-01

    The Conservatism in Typical Vibration Tests was Demonstrated: Vibration test at component level produced conservative force reactions by approximately a factor of 4 (approx.12 dB) as compared to the integrated acoustic test in 2 out of 3 axes. Reaction Forces Estimated at the Base of Equipment Using a Finite Element Based Method were Validated: FEM based estimate of interface forces may be adequate to guide development of vibration test criteria with less conservatism. Element Forces Estimated in Secondary Structure Struts were Validated: Finite element approach provided best estimate of axial strut forces in frequency range below 200 Hz where a rigid lumped mass assumption for the entire electronics box was valid. Models with enough fidelity to represent diminishing apparent mass of equipment are better suited for estimating force reactions across the frequency range. Forward Work: Demonstrate the reduction in conservatism provided by; Current force limited approach and an FEM guided approach. Validate proposed CMS approach to estimate coupled response from uncoupled system characteristics for vibroacoustics.

  1. The Alcock Paczy'nski test with Baryon Acoustic Oscillations: systematic effects for future surveys

    Science.gov (United States)

    Lepori, Francesca; Di Dio, Enea; Viel, Matteo; Baccigalupi, Carlo; Durrer, Ruth

    2017-02-01

    We investigate the Alcock Paczy'nski (AP) test applied to the Baryon Acoustic Oscillation (BAO) feature in the galaxy correlation function. By using a general formalism that includes relativistic effects, we quantify the importance of the linear redshift space distortions and gravitational lensing corrections to the galaxy number density fluctuation. We show that redshift space distortions significantly affect the shape of the correlation function, both in radial and transverse directions, causing different values of galaxy bias to induce offsets up to 1% in the AP test. On the other hand, we find that the lensing correction around the BAO scale modifies the amplitude but not the shape of the correlation function and therefore does not introduce any systematic effect. Furthermore, we investigate in details how the AP test is sensitive to redshift binning: a window function in transverse direction suppresses correlations and shifts the peak position toward smaller angular scales. We determine the correction that should be applied in order to account for this effect, when performing the test with data from three future planned galaxy redshift surveys: Euclid, the Dark Energy Spectroscopic Instrument (DESI) and the Square Kilometer Array (SKA).

  2. A research program to reduce interior noise in general aviation airplanes. Design of an acoustic panel test facility

    Science.gov (United States)

    Roskam, J.; Muirhead, V. U.; Smith, H. W.; Henderson, T. D.

    1977-01-01

    The design, construction, and costs of a test facility for determining the sound transmission loss characteristics of various panels and panel treatments are described. The pressurization system and electronic equipment used in experimental testing are discussed as well as the reliability of the facility and the data gathered. Tests results are compared to pertinent acoustical theories for panel behavior and minor anomalies in the data are examined. A method for predicting panel behavior in the stiffness region is also presented.

  3. Can you hear me now? Range-testing a submerged passive acoustic receiver array in a Caribbean coral reef habitat

    Science.gov (United States)

    Selby, Thomas H.; Hart, Kristen M.; Fujisaki, Ikuko; Smith, Brian J.; Pollock, Clayton J; Hillis-Star, Zandy M; Lundgren, Ian; Oli, Madan K.

    2016-01-01

    Submerged passive acoustic technology allows researchers to investigate spatial and temporal movement patterns of many marine and freshwater species. The technology uses receivers to detect and record acoustic transmissions emitted from tags attached to an individual. Acoustic signal strength naturally attenuates over distance, but numerous environmental variables also affect the probability a tag is detected. Knowledge of receiver range is crucial for designing acoustic arrays and analyzing telemetry data. Here, we present a method for testing a relatively large-scale receiver array in a dynamic Caribbean coastal environment intended for long-term monitoring of multiple species. The U.S. Geological Survey and several academic institutions in collaboration with resource management at Buck Island Reef National Monument (BIRNM), off the coast of St. Croix, recently deployed a 52 passive acoustic receiver array. We targeted 19 array-representative receivers for range-testing by submersing fixed delay interval range-testing tags at various distance intervals in each cardinal direction from a receiver for a minimum of an hour. Using a generalized linear mixed model (GLMM), we estimated the probability of detection across the array and assessed the effect of water depth, habitat, wind, temperature, and time of day on the probability of detection. The predicted probability of detection across the entire array at 100 m distance from a receiver was 58.2% (95% CI: 44.0–73.0%) and dropped to 26.0% (95% CI: 11.4–39.3%) 200 m from a receiver indicating a somewhat constrained effective detection range. Detection probability varied across habitat classes with the greatest effective detection range occurring in homogenous sand substrate and the smallest in high rugosity reef. Predicted probability of detection across BIRNM highlights potential gaps in coverage using the current array as well as limitations of passive acoustic technology within a complex coral reef

  4. Evaluation of the Acoustic Measurement Capability of the NASA Langley V/STOL Wind Tunnel Open Test Section with Acoustically Absorbent Ceiling and Floor Treatments

    Science.gov (United States)

    Theobald, M. A.

    1978-01-01

    The single source location used for helicopter model studies was utilized in a study to determine the distances and directions upstream of the model accurate at which measurements of the direct acoustic field could be obtained. The method used was to measure the decrease of sound pressure levels with distance from a noise source and thereby determine the Hall radius as a function of frequency and direction. Test arrangements and procedures are described. Graphs show the normalized sound pressure level versus distance curves for the glass fiber floor treatment and for the foam floor treatment.

  5. Comparative evaluation of Space Transportation System (STS)-3 flight and acoustic test random vibration response of the OSS-1 payload

    Science.gov (United States)

    On, F. J.

    1983-01-01

    A comparative evaluation of the Space Transportation System (STS)-3 flight and acoustic test random vibration response of the Office of Space Science-1 (OSS-1) payload is presented. The results provide insight into the characteristics of vibroacoustic response of pallet payload components in the payload bay during STS flights.

  6. Preliminary vibration, acoustic, and shock design and test criteria for components on the Lightweight External Tank (LWT)

    Science.gov (United States)

    1981-01-01

    The Space Shuttle LWT is divided into zones and subzones. Zones are designated primarily to assist in determining the applicable specifications. A subzone (general Specification) is available for use when the location of the component is known but component design and weight are not well defined. When the location, weight, and mounting configuration of the component are known, specifications for appropriate subzone weight ranges are available. Along with the specifications are vibration, acoustic, shock, transportation, handling, and acceptance test requirements and procedures. A method of selecting applicable vibration, acoustic, and shock specifications is presented.

  7. The application of the acoustic emission technique to stone decay by sodium sulphate in laboratory tests

    Directory of Open Access Journals (Sweden)

    Grossi, C. M.

    1997-03-01

    Full Text Available Acoustic emission was monitored during salt crystallisation cycles in order to study the mechanisms of rock deterioration by sodium sulphate in laboratory tests. Some porous carbonate stones used in Spanish monuments (Cathedral of Oviedo, Murcia and Seo Vella of Lérida were selected for this study. The acoustic emission detected during the different stages of the cycles (immersion, drying and cooling was interpreted to be the result of the salt behaviour inside the stone. The use of this technique has confirmed that this behaviour depends on salt characteristics (solubility, hydration state and polymorphism of anhydrous sodium sulphate and stone porosity and pore network.

    Para determinar los mecanismos de deterioro de las rocas debidos a la acción del sulfato de sodio, se ha registrado la emisión acústica durante ensayos de cristalización de sales en el laboratorio. Para ello, se han seleccionado tres piedras porosas carbonatadas utilizadas como materiales de construcción en monumentos españoles (Catedrales de Oviedo, Murcia y Seo Vella de Lérida. La emisión acústica detectada durante las diferentes etapas de los ciclos (inmersión, secado y enfriamiento se ha interpretado como debida al comportamiento de la sal en el interior de la piedra. Mediante esta técnica se ha confirmado que este comportamiento depende de las características de la sal (solubilidad, diferentes estados de hidratación y el polimorfismo del sulfato de sodio anhidro y de la porosidad y configuración del sistema poroso de las rocas.

  8. Testing of containers made of glass-fiber reinforced plastic with the aid of acoustic emission analysis

    Science.gov (United States)

    Wolitz, K.; Brockmann, W.; Fischer, T.

    1979-01-01

    Acoustic emission analysis as a quasi-nondestructive test method makes it possible to differentiate clearly, in judging the total behavior of fiber-reinforced plastic composites, between critical failure modes (in the case of unidirectional composites fiber fractures) and non-critical failure modes (delamination processes or matrix fractures). A particular advantage is that, for varying pressure demands on the composites, the emitted acoustic pulses can be analyzed with regard to their amplitude distribution. In addition, definite indications as to how the damages occurred can be obtained from the time curves of the emitted acoustic pulses as well as from the particular frequency spectrum. Distinct analogies can be drawn between the various analytical methods with respect to whether the failure modes can be classified as critical or non-critical.

  9. 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

  10. Vibration, acoustic, and shock design and test criteria for components on the Solid Rocket Boosters (SRB), Lightweight External Tank (LWT), and Space Shuttle Main Engines (SSME)

    Science.gov (United States)

    1984-01-01

    The vibration, acoustics, and shock design and test criteria for components and subassemblies on the space shuttle solid rocket booster (SRB), lightweight tank (LWT), and main engines (SSME) are presented. Specifications for transportation, handling, and acceptance testing are also provided.

  11. Experimental Setups for Single Event Effect Studies

    Directory of Open Access Journals (Sweden)

    N. H. Medina

    2016-08-01

    Full Text Available Experimental setups are being prepared to test and to qualify electronic devices regarding their tolerance to Single Event Effect (SEE. A multiple test setup and a new beam line developed especially for SEE studies at the São Paulo 8 UD Pelletron accelerator were prepared. This accelerator produces proton beams and heavy ion beams up to 107Ag. A Super conducting Linear accelerator, which is under construction, may fulfill all of the European Space Agency requirements to qualify electronic components for SEE.

  12. AMADEUS - The Acoustic Neutrino Detection Test System of the ANTARES Deep-Sea Neutrino Telescope

    CERN Document Server

    Aguilar, J A; Albert, A; Anghinolfi, M; Anton, G; Anvar, S; Ardid, M; Jesus, A C Assis; Astraatmadja, T; Aubert, J-J; Auer, R; Barbarito, E; Baret, B; Basa, S; Bazzotti, M; Bertin, V; Biagi, S; Bigongiari, C; Bou-Cabo, M; Bouwhuis, M C; Brown, A; Brunner, J; Busto, J; Camarena, F; Capone, A; Cârloganu, C; Carminati, G; Carr, J; Cassano, B; Castorina, E; Cavasinni, V; Cecchini, S; Ceres, A; Charvis, Ph; Chiarusi, T; Sen, N Chon; Circella, M; Coniglione, R; Costantini, H; Cottini, N; Coyle, P; Curtil, C; De Bonis, G; Decowski, M P; Dekeyser, I; Deschamps, A; Distefano, C; Donzaud, C; Dornic, D; Drouhin, D; Eberl, T; Emanuele, U; Ernenwein, J-P; Escoffier, S; Fehr, F; Fiorello, C; Flaminio, V; Fritsch, U; Fuda, J-L; Gay, P; Giacomelli, G; Gómez-González, J P; Graf, K; Guillard, G; Halladjian, G; Hallewell, G; van Haren, H; Heijboer, A J; Heine, E; Hello, Y; Hernández-Rey, J J; Herold, B; Hößl, J; de Jong, M; Kalantar-Nayestanaki, N; Kalekin, O; Kappes, A; Katz, U; Keller, P; Kooijman, P; Kopper, C; Kouchner, A; Kretschmer, W; Lahmann, R; Lamare, P; Lambard, G; Larosa, G; Laschinsky, H; Le Provost, H; Lefèvre, D; Lelaizant, G; Lim, G; Presti, D Lo; Loehner, H; Loucatos, S; Louis, F; Lucarelli, F; Mangano, S; Marcelin, M; Margiotta, A; Martinez-Mora, J A; Mazure, A; Mongelli, M; Montaruli, T; Morganti, M; Moscoso, L; Motz, H; Naumann, C; Neff, M; Ostasch, R; Palioselitis, D; Pavalas, G E; Payre, P; Petrovic, J; Picot-Clemente, N; Picq, C; Popa, V; Pradier, T; Presani, E; Racca, C; Radu, A; Reed, C; Riccobene, G; Richardt, C; Rujoiu, M; Ruppi, M; Russo, G V; Salesa, F; Sapienza, P; Schöck, F; Schuller, J-P; Shanidze, R; Simeone, F; Spurio, M; Steijger, J J M; Stolarczyk, Th; Taiuti, M; Tamburini, C; Tasca, L; Toscano, S; Vallage, B; Van Elewyck, V; Vannoni, G; Vecchi, M; Vernin, P; Wijnker, G; de Wolf, E; Yepes, H; Zaborov, D; Zornoza, J D; Zúñiga, J; 10.1016/j.nima.2010.09.053

    2010-01-01

    The AMADEUS (ANTARES Modules for the Acoustic Detection Under the Sea) system which is described in this article aims at the investigation of techniques for acoustic detection of neutrinos in the deep sea. It is integrated into the ANTARES neutrino telescope in the Mediterranean Sea. Its acoustic sensors, installed at water depths between 2050 and 2300 m, employ piezo-electric elements for the broad-band recording of signals with frequencies ranging up to 125 kHz. The typical sensitivity of the sensors is around -145 dB re 1V/muPa (including preamplifier). Completed in May 2008, AMADEUS consists of six "acoustic clusters", each comprising six acoustic sensors that are arranged at distances of roughly 1 m from each other. Two vertical mechanical structures (so-called lines) of the ANTARES detector host three acoustic clusters each. Spacings between the clusters range from 14.5 to 340 m. Each cluster contains custom-designed electronics boards to amplify and digitise the acoustic signals from the sensors. An on...

  13. Reproducibility experiments on measuring acoustical properties of rigid-frame porous media (round-robin tests).

    Science.gov (United States)

    Horoshenkov, Kirill V; Khan, Amir; Bécot, François-Xavier; Jaouen, Luc; Sgard, Franck; Renault, Amélie; Amirouche, Nesrine; Pompoli, Francesco; Prodi, Nicola; Bonfiglio, Paolo; Pispola, Giulio; Asdrubali, Francesco; Hübelt, Jörn; Atalla, Noureddine; Amédin, Celse K; Lauriks, Walter; Boeckx, Laurens

    2007-07-01

    This paper reports the results of reproducibility experiments on the interlaboratory characterization of the acoustical properties of three types of consolidated porous media: granulated porous rubber, reticulated foam, and fiberglass. The measurements are conducted in several independent laboratories in Europe and North America. The studied acoustical characteristics are the surface complex acoustic impedance at normal incidence and plane wave absorption coefficient which are determined using the standard impedance tube method. The paper provides detailed procedures related to sample preparation and installation and it discusses the dispersion in the acoustical material property observed between individual material samples and laboratories. The importance of the boundary conditions, homogeneity of the porous material structure, and stability of the adopted signal processing method are highlighted.

  14. AMADEUS—The acoustic neutrino detection test system of the ANTARES deep-sea neutrino telescope

    Science.gov (United States)

    Aguilar, J. A.; Al Samarai, I.; Albert, A.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Baret, B.; Basa, S.; Bazzotti, M.; Bertin, V.; Biagi, S.; Bigongiari, C.; Bou-Cabo, M.; Bouwhuis, M. C.; Brown, A.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Cârloganu, C.; Carminati, G.; Carr, J.; Cassano, B.; Castorina, E.; Cavasinni, V.; Cecchini, S.; Ceres, A.; Charvis, Ph.; Chiarusi, T.; Chon Sen, N.; Circella, M.; Coniglione, R.; Costantini, H.; Cottini, N.; Coyle, P.; Curtil, C.; de Bonis, G.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Drouhin, D.; Eberl, T.; Emanuele, U.; Ernenwein, J.-P.; Escoffier, S.; Fehr, F.; Fiorello, C.; Flaminio, V.; Fritsch, U.; Fuda, J.-L.; Gay, P.; Giacomelli, G.; Gómez-González, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Heijboer, A. J.; Heine, E.; Hello, Y.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; de Jong, M.; Kalantar-Nayestanaki, N.; Kalekin, O.; Kappes, A.; Katz, U.; Keller, P.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kretschmer, W.; Lahmann, R.; Lamare, P.; Lambard, G.; Larosa, G.; Laschinsky, H.; Le Provost, H.; Lefèvre, D.; Lelaizant, G.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J. A.; Mazure, A.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Motz, H.; Naumann, C.; Neff, M.; Ostasch, R.; Palioselitis, D.; Păvălaş, G. E.; Payre, P.; Petrovic, J.; Picot-Clemente, N.; Picq, C.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Radu, A.; Reed, C.; Riccobene, G.; Richardt, C.; Rujoiu, M.; Ruppi, M.; Russo, G. V.; Salesa, F.; Sapienza, P.; Schöck, F.; Schuller, J.-P.; Shanidze, R.; Simeone, F.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Taiuti, M.; Tamburini, C.; Tasca, L.; Toscano, S.; Vallage, B.; van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wijnker, G.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zúñiga, J.

    2011-01-01

    The AMADEUS (ANTARES Modules for the Acoustic Detection Under the Sea) system which is described in this article aims at the investigation of techniques for acoustic detection of neutrinos in the deep sea. It is integrated into the ANTARES neutrino telescope in the Mediterranean Sea. Its acoustic sensors, installed at water depths between 2050 and 2300 m, employ piezo-electric elements for the broad-band recording of signals with frequencies ranging up to 125 kHz. The typical sensitivity of the sensors is around -145 dB re 1 V/μPa (including preamplifier). Completed in May 2008, AMADEUS consists of six “acoustic clusters”, each comprising six acoustic sensors that are arranged at distances of roughly 1 m from each other. Two vertical mechanical structures (so-called lines) of the ANTARES detector host three acoustic clusters each. Spacings between the clusters range from 14.5 to 340 m. Each cluster contains custom-designed electronics boards to amplify and digitise the acoustic signals from the sensors. An on-shore computer cluster is used to process and filter the data stream and store the selected events. The daily volume of recorded data is about 10 GB. The system is operating continuously and automatically, requiring only little human intervention. AMADEUS allows for extensive studies of both transient signals and ambient noise in the deep sea, as well as signal correlations on several length scales and localisation of acoustic point sources. Thus the system is excellently suited to assess the background conditions for the measurement of the bipolar pulses expected to originate from neutrino interactions.

  15. A methodology to condition distorted acoustic emission signals to identify fracture timing from human cadaver spine impact tests.

    Science.gov (United States)

    Arun, Mike W J; Yoganandan, Narayan; Stemper, Brian D; Pintar, Frank A

    2014-12-01

    While studies have used acoustic sensors to determine fracture initiation time in biomechanical studies, a systematic procedure is not established to process acoustic signals. The objective of the study was to develop a methodology to condition distorted acoustic emission data using signal processing techniques to identify fracture initiation time. The methodology was developed from testing a human cadaver lumbar spine column. Acoustic sensors were glued to all vertebrae, high-rate impact loading was applied, load-time histories were recorded (load cell), and fracture was documented using CT. Compression fracture occurred to L1 while other vertebrae were intact. FFT of raw voltage-time traces were used to determine an optimum frequency range associated with high decibel levels. Signals were bandpass filtered in this range. Bursting pattern was found in the fractured vertebra while signals from other vertebrae were silent. Bursting time was associated with time of fracture initiation. Force at fracture was determined using this time and force-time data. The methodology is independent of selecting parameters a priori such as fixing a voltage level(s), bandpass frequency and/or using force-time signal, and allows determination of force based on time identified during signal processing. The methodology can be used for different body regions in cadaver experiments.

  16. Nondestructive testing: use of IR and acoustics methods in buildings pathology

    Science.gov (United States)

    Esposti, Walter; Meroni, Italo

    1995-03-01

    In the paper the authors present some experiences made using IR and acoustics methods in a non destructive way for the evaluation of situations of degradation in building materials and components. Two studies are presented: (1) detection of the delamination of wall renderings, especially those supporting frescos, by means of IR and sonic investigation; (2) use of infrared thermography for the visualization of fracture zones of walls and steel components under cyclic loads. The possibility of detecting rendering delaminations is based on the different path of the heat diffusion in part of the wall affected by the delamination, compared to the rest of the wall. The difference is caused by the presence of small pockets containing still air. The case study showed makes reference to the analysis of adhesion conditions of a rendering dating back to the IV century, applied on the bell towers of the ancient basilica dedicated to S. Lorenzo in Milan, Italy. The use of infrared thermography for detecting the strength status of materials and components is based on the fact that the strength status of parts of building components can become evident because of heat losses which appear where the component is weaker. The IR observation was made on steel bars subject to traction testing and on lightweight concrete prismatic samples subject to compression testing. The experiences indicate that there is room for this NdT technique to provide some useful answers. Nevertheless it is sure that more experimental work is needed in order to increase the full comprehension of the phenomena which are the basis of their applications for alternative uses.

  17. 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....

  18. A multi-channel setup to study fractures in scintillators

    Science.gov (United States)

    Tantot, A.; Bouard, C.; Briche, R.; Lefèvre, G.; Manier, B.; Zaïm, N.; Deschanel, S.; Vanel, L.; Di Stefano, P. C. F.

    2016-12-01

    To investigate fractoluminescence in scintillating crystals used for particle detection, we have developed a multi-channel setup built around samples of double-cleavage drilled compression (DCDC) geometry in a controllable atmosphere. The setup allows the continuous digitization over hours of various parameters, including the applied load, and the compressive strain of the sample, as well as the acoustic emission. Emitted visible light is recorded with nanosecond resolution, and crack propagation is monitored using infrared lighting and camera. An example of application to \\text{B}{{\\text{i}}4}\\text{G}{{\\text{e}}3}{{\\text{O}}12} (BGO) is provided.

  19. A Multi-Channel Setup to Study Fractures in Scintillators

    CERN Document Server

    Tantot, A; Briche, R; Lefèvre, G; Manier, B; Zaïm, N; Deschanel, S; Vanel, L; Di Stefano, P C F

    2016-01-01

    To investigate fractoluminescence in scintillating crystals used for particle detection, we have developed a multi-channel setup built around samples of double-cleavage drilled compression (DCDC) geometry in a controllable atmosphere. The setup allows the continuous digitization over hours of various parameters, including the applied load, and the compressive strain of the sample, as well as the acoustic emission. Emitted visible light is recorded with nanosecond resolution, and crack propagation is monitored using infrared lighting and camera. An example of application to Bi4Ge3O12 (BGO) is provided.

  20. Status and Recent Results of the Acoustic Neutrino Detection Test System AMADEUS

    CERN Document Server

    ,

    2011-01-01

    The AMADEUS system is an integral part of the ANTARES neutrino telescope in the Mediterranean Sea. The project aims at the investigation of techniques for acoustic neutrino detection in the deep sea. Installed at a depth of more than 2000m, the acoustic sensors of AMADEUS are based on piezo-ceramics elements for the broad-band recording of signals with frequencies ranging up to 125kHz. AMADEUS was completed in May 2008 and comprises six "acoustic clusters", each one holding six acoustic sensors that are arranged at distances of roughly 1m from each other. The clusters are installed with inter-spacings ranging from 15m to 340m. Acoustic data are continuously acquired and processed at a computer cluster where online filter algorithms are applied to select a high-purity sample of neutrino-like signals. 1.6 TB of data were recorded in 2008 and 3.2 TB in 2009. In order to assess the background of neutrino-like signals in the deep sea, the characteristics of ambient noise and transient signals have been investigate...

  1. Performance of velocity vector estimation using an improved dynamic beamforming setup

    DEFF Research Database (Denmark)

    Munk, Peter; Jensen, Jørgen Arendt

    2001-01-01

    control of the acoustic field, based on the Pulsed Plane Wave Decomposition (PPWD), is presented. The PPWD gives an unambigious relation between a given acoustic field and the time functions needed on an array transducer for transmission. Applying this method for the receive beamformation results in a set......-up of the beamformer with different filters for each channel for each estimation depth. The method of the PPWD is illustrated by analytical expressions of the decomposed acoustic field and these results are used for simulation. Results of velocity estimates using the new setup are given on the basis of simulated...

  2. Acoustic noise in deep ice and environmental conditions at the South Pole

    CERN Document Server

    Karg, Timo

    2008-01-01

    To study the acoustic properties of the Antarctic ice the South Pole Acoustic Test Setup (SPATS) was installed in the upper part of drill holes for the IceCube neutrino observatory. An important parameter for the design of a future acoustic neutrino telescope is the acoustic background noise in the ice and its spatial and temporal variations. We study the absolute noise level depth profile from SPATS data and discuss systematic uncertainties. The measured noise is very stable over one year of data taking, and we estimate the absolute noise level to be < 10 mPa in the frequency range from 10 kHz to 50 kHz at depths below 200 m. This noise level is of the same order of magnitude as observed by ocean based acoustic neutrino detection projects in good weather conditions.

  3. Towards Truly Quiet MRI: animal MRI magnetic field gradients as a test platform for acoustic noise reduction

    Science.gov (United States)

    Edelstein, William; El-Sharkawy, Abdel-Monem

    2013-03-01

    Clinical MRI acoustic noise, often substantially exceeding 100 dB, causes patient anxiety and discomfort and interferes with functional MRI (fMRI) and interventional MRI. MRI acoustic noise reduction is a long-standing and difficult technical challenge. The noise is basically caused by large Lorentz forces on gradient windings--surrounding the patient bore--situated in strong magnetic fields (1.5 T, 3 T or higher). Pulsed currents of 300 A or more are switched through the gradient windings in sub-milliseconds. Experimenting with hardware noise reduction on clinical scanners is difficult and expensive because of the large scale and weight of clinical scanner components (gradient windings ~ 1000 kg) that require special handling equipment in large engineering test facilities. Our approach is to produce a Truly Quiet (test platform for acoustic noise reduction measures that can be implemented in clinical scanners. We have so far decreased noise in an animal scale imager from 108 dB to 71 dB, a 37 dB reduction. Our noise reduction measures include: a gradient container that can be evacuated; inflatable antivibration mounts to prevent transmission of vibrations from gradient winding to gradient container; vibration damping of wires going from gradient to the outside world via the gradient container; and a copper passive shield to prevent the generation of eddy currents in the metal cryostat inner bore, which in turn can vibrate and produce noise.

  4. Acoustic Data Processing and Transient Signal Analysis for the Hybrid Wing Body 14- by 22-Foot Subsonic Wind Tunnel Test

    Science.gov (United States)

    Bahr, Christopher J.; Brooks, Thomas F.; Humphreys, William M.; Spalt, Taylor B.; Stead, Daniel J.

    2014-01-01

    An advanced vehicle concept, the HWB N2A-EXTE aircraft design, was tested in NASA Langley's 14- by 22-Foot Subsonic Wind Tunnel to study its acoustic characteristics for var- ious propulsion system installation and airframe con gurations. A signi cant upgrade to existing data processing systems was implemented, with a focus on portability and a re- duction in turnaround time. These requirements were met by updating codes originally written for a cluster environment and transferring them to a local workstation while en- abling GPU computing. Post-test, additional processing of the time series was required to remove transient hydrodynamic gusts from some of the microphone time series. A novel automated procedure was developed to analyze and reject contaminated blocks of data, under the assumption that the desired acoustic signal of interest was a band-limited sta- tionary random process, and of lower variance than the hydrodynamic contamination. The procedure is shown to successfully identify and remove contaminated blocks of data and retain the desired acoustic signal. Additional corrections to the data, mainly background subtraction, shear layer refraction calculations, atmospheric attenuation and microphone directivity corrections, were all necessary for initial analysis and noise assessments. These were implemented for the post-processing of spectral data, and are shown to behave as expected.

  5. Preliminary vibration, acoustic, and shock design and test criteria for components on the SRB, ET, and SSME

    Science.gov (United States)

    1976-01-01

    Specifications for vibration, acoustic and shock design for components and subassemblies on the External Tank (ET), Solid Rocket Booster (SRB), and Space Shuttle Main Engine (SSME). Included are vibration, acoustic, shock, transportation, handling, and acceptance test requirements and procedures. The space shuttle ET, SRB, and SSME have been divided into zones and subzones. Zones are designated primarily to assist in determining the applicable specifications. A subzone (General Specification) is available for use when the location of the component is known but component design and weight are not well defined. When the location, weight, and mounting configuration of the component are known, specifications for appropriate subzone weight ranges are available. Criteria for some specific components are also presented.

  6. Sensor development and calibration for acoustic neutrino detection in ice

    CERN Document Server

    Karg, Timo; Laihem, Karim; Semburg, Benjamin; Tosi, Delia

    2009-01-01

    A promising approach to measure the expected low flux of cosmic neutrinos at the highest energies (E > 1 EeV) is acoustic detection. There are different in-situ test installations worldwide in water and ice to measure the acoustic properties of the medium with regard to the feasibility of acoustic neutrino detection. The parameters of interest include attenuation length, sound speed profile, background noise level and transient backgrounds. The South Pole Acoustic Test Setup (SPATS) has been deployed in the upper 500 m of drill holes for the IceCube neutrino observatory at the geographic South Pole. In-situ calibration of sensors under the combined influence of low temperature, high ambient pressure, and ice-sensor acoustic coupling is difficult. We discuss laboratory calibrations in water and ice. Two new laboratory facilities, the Aachen Acoustic Laboratory (AAL) and the Wuppertal Water Tank Test Facility, have been set up. They offer large volumes of bubble free ice (3 m^3) and water (11 m^3) for the devel...

  7. SIMONA: A multi-purpose acoustic data simulator for development and testing of sonar signal processing

    NARCIS (Netherlands)

    Robert, M.K.; Groen, J.; Konijnendijk, N.J.

    2005-01-01

    The development of undersea defence technologies such as sonar relies heavily on the availability of high quality acoustic data. However, data acquisition is particularly expensive as sea trials involve experienced manpower and costly high-tech equipment. Also, at sea, the environment remains unpred

  8. Wideband Acoustic Immittance: Normative Study and Test-Retest Reliability of Tympanometric Measurements in Adults

    Science.gov (United States)

    Sun, Xiao-Ming

    2016-01-01

    Purpose: The purpose of this study was to present normative data of tympanometric measurements of wideband acoustic immittance and to characterize wideband tympanograms. Method: Data were collected in 84 young adults with strictly defined normal hearing and middle ear status. Energy absorbance (EA) was measured using clicks for 1/12-octave…

  9. Experimental investigation of shock-cell noise reduction for dual-stream nozzles in simulated flight comprehensive data report. Volume 1: Test nozzles and acoustic data

    Science.gov (United States)

    Yamamoto, K.; Janardan, B. A.; Brausch, J. F.; Hoerst, D. J.; Price, A. O.

    1984-01-01

    Parameters which contribute to supersonic jet shock noise were investigated for the purpose of determining means to reduce such noise generation to acceptable levels. Six dual-stream test nozzles with varying flow passage and plug closure designs were evaluated under simulated flight conditions in an anechoic chamber. All nozzles had combined convergent-divergent or convergent flow passages. Acoustic behavior as a function of nozzle flow passage geometry was measured. The acoustic data consist primarily of 1/3 octave band sound pressure levels and overall sound pressure levels. Detailed schematics and geometric characteristics of the six scale model nozzle configurations and acoustic test point definitions are presented. Tabulation of aerodynamic test conditions and a computer listing of the measured acoustic data are displayed.

  10. High-fidelity simulation capability for virtual testing of seismic and acoustic sensors

    Science.gov (United States)

    Wilson, D. Keith; Moran, Mark L.; Ketcham, Stephen A.; Lacombe, James; Anderson, Thomas S.; Symons, Neill P.; Aldridge, David F.; Marlin, David H.; Collier, Sandra L.; Ostashev, Vladimir E.

    2005-05-01

    This paper describes development and application of a high-fidelity, seismic/acoustic simulation capability for battlefield sensors. The purpose is to provide simulated sensor data so realistic that they cannot be distinguished by experts from actual field data. This emerging capability provides rapid, low-cost trade studies of unattended ground sensor network configurations, data processing and fusion strategies, and signatures emitted by prototype vehicles. There are three essential components to the modeling: (1) detailed mechanical signature models for vehicles and walkers, (2) high-resolution characterization of the subsurface and atmospheric environments, and (3) state-of-the-art seismic/acoustic models for propagating moving-vehicle signatures through realistic, complex environments. With regard to the first of these components, dynamic models of wheeled and tracked vehicles have been developed to generate ground force inputs to seismic propagation models. Vehicle models range from simple, 2D representations to highly detailed, 3D representations of entire linked-track suspension systems. Similarly detailed models of acoustic emissions from vehicle engines are under development. The propagation calculations for both the seismics and acoustics are based on finite-difference, time-domain (FDTD) methodologies capable of handling complex environmental features such as heterogeneous geologies, urban structures, surface vegetation, and dynamic atmospheric turbulence. Any number of dynamic sources and virtual sensors may be incorporated into the FDTD model. The computational demands of 3D FDTD simulation over tactical distances require massively parallel computers. Several example calculations of seismic/acoustic wave propagation through complex atmospheric and terrain environments are shown.

  11. Interexaminer and intraexaminer reliabilities of 3-dimensional orthodontic digital setups

    NARCIS (Netherlands)

    Fabels, L.N.J.; Nijkamp, P.G.

    2014-01-01

    Introduction The use of digital orthodontic setups has grown quickly. The purpose of this study was to test the interexaminer and intraexaminer reliabilities of 3-dimensional orthodontic digital setups in OrthoCAD (Align Technology, San Jose, Calif). Methods Six clinicians made digital orthodontic s

  12. ISSUES AND FEASIBILITY DEMONSTRATION OF CLIC SUPPORTING SYSTEM CHAIN ACTIVE PRE-ALIGNMENT USING A MULTI-MODULE TEST SETUP (MOCK-UP)

    CERN Document Server

    Sosin, Mateusz

    2016-01-01

    The implementation study of the CLIC (Compact LInear Collider) is under way at CERN with a focus on the challenging issues. The pre-alignment precision and accuracy requirements are part of these technical challenges: the permissible transverse position errors of the linac components are typically 14 micrometers over sliding windows of 200m. To validate the proposed methods and strategies, the Large Scale Metrology section at CERN has performed campaigns of measurements on the CLIC Two Beam Test Modules, focusing inter alia on the alignment performance of the CLIC “snake”- girders configuration and the Main Beam Quadrupoles supporting structures. This paper describes the activities and results of tests which were performed on the test mock-up for the qualification of the CLIC supporting system chain for active pre-alignment. The lessons learnt (“know how”), the issues encountered in the girder position determination as well as the behaviour of the mechanical components are presented.

  13. AMELIA CESTOL Test: Acoustic Characteristics of Circulation Control Wing with Leading- and Trailing-Edge Slot Blowing

    Science.gov (United States)

    Horne, William C.; Burnside, Nathan J.

    2013-01-01

    The AMELIA Cruise-Efficient Short Take-off and Landing (CESTOL) configuration concept was developed to meet future requirements of reduced field length, noise, and fuel burn by researchers at Cal Poly, San Luis Obispo and Georgia Tech Research Institute under sponsorship by the NASA Fundamental Aeronautics Program (FAP), Subsonic Fixed Wing Project. The novel configuration includes leading- and trailing-edge circulation control wing (CCW), over-wing podded turbine propulsion simulation (TPS). Extensive aerodynamic measurements of forces, surfaces pressures, and wing surface skin friction measurements were recently measured over a wide range of test conditions in the Arnold Engineering Development Center(AEDC) National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-Ft Wind Tunnel. Acoustic measurements of the model were also acquired for each configuration with 7 fixed microphones on a line under the left wing, and with a 48-element, 40-inch diameter phased microphone array under the right wing. This presentation will discuss acoustic characteristics of the CCW system for a variety of tunnel speeds (0 to 120 kts), model configurations (leading edge(LE) and/or trailing-edge(TE) slot blowing, and orientations (incidence and yaw) based on acoustic measurements acquired concurrently with the aerodynamic measurements. The flow coefficient, Cmu= mVSLOT/qSW varied from 0 to 0.88 at 40 kts, and from 0 to 0.15 at 120 kts. Here m is the slot mass flow rate, VSLOT is the slot exit velocity, q is dynamic pressure, and SW is wing surface area. Directivities at selected 1/3 octave bands will be compared with comparable measurements of a 2-D wing at GTRI, as will as microphone array near-field measurements of the right wing at maximum flow rate. The presentation will include discussion of acoustic sensor calibrations as well as characterization of the wind tunnel background noise environment.

  14. Model Test Setup and Program for Experimental Estimation of Surface Loads of the SSG Kvitsøy Pilot Plant from Extreme Wave Conditions

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Larsen, Brian Juul

    This report presents the preparations done prior to model tests planned for November 2005 focusing on experimental estimation of the surface loads on the wave energy convert (WEC) Seawave Slot-Cone Generator (SSG) due to extreme wave conditions. SSG is a WEC utilizing wave overtopping in multiple...

  15. Acoustic Noise Test Report for the U.S. Department of Energy 1.5-Megawatt Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Roadman, Jason [National Renewable Energy Lab. (NREL), Golden, CO (United States); Huskey, Arlinda [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-07-01

    A series of tests were conducted to characterize the baseline properties and performance of the U.S. Department of Energy (DOE) 1.5-megawatt wind turbine (DOE 1.5) to enable research model development and quantify the effects of future turbine research modifications. The DOE 1.5 is built on the platform of GE's 1.5-MW SLE commercial wind turbine model. It was installed in a nonstandard configuration at the NWTC with the objective of supporting DOE Wind Program research initiatives such as A2e. Therefore, the test results may not represent the performance capabilities of other GE 1.5-MW SLE turbines. The acoustic noise test documented in this report is one of a series of tests carried out to establish a performance baseline for the DOE 1.5 in the NWTC inflow environment.

  16. Testing Thermo-acoustic Sound Generation in Water with Proton and Laser Beams

    CERN Document Server

    Graf, K; Hoessl, J; Kappes, A; Karg, T; Katz, U; Lahmann, R; Naumann, C; Salomon, K; Stegmann, C

    2005-01-01

    Experiments were performed at a proton accelerator and an infrared laser acility to investigate the sound generation caused by the energy deposition of pulsed particle and laser beams in water. The beams with an energy range of 1 PeV to 400 PeV per proton beam spill and up to 10 EeV for the laser pulse were dumped into a water volume and the resulting acoustic signals were recorded with pressure sensitive sensors. Measurements were performed at varying pulse energies, sensor positions, beam diameters and temperatures. The data is well described by simulations based on the thermo-acoustic model. This implies that the primary mechanism for sound generation by the energy deposition of particles propagating in water is the local heating of the media giving rise to an expansion or contraction of the medium resulting in a pressure pulse with bipolar shape. A possible application of this effect would be the acoustical detection of neutrinos with energies greater than 1 EeV.

  17. A seismic field test with a Low-level Acoustic Combustion Source and Pseudo-Noise codes

    Science.gov (United States)

    Askeland, Bjørn; Ruud, Bent Ole; Hobæk, Halvor; Mjelde, Rolf

    2009-01-01

    The Low-level Acoustic Combustion Source (LACS) which can fire its pulses at a high rate, has been tested successfully as a seismic marine source on shallow ice-age sediments in Byfjorden at Bergen, Norway. Pseudo-Noise pulsed signals with spiky autocorrelation functions were used to detect the sediments. Each transmitted sequence lasted 10 s and contained 43 pulses. While correlation gave a blurry result, deconvolution between the near-field recordings and the streamer recordings gave a clear seismic section. Compared to the section acquired with single air-gun shots along the same profile, the LACS gave a more clear presentation of the sediments and basement.

  18. Preliminary vibration, acoustic, and shock design and test criteria for components on the HEAO-A spacecraft

    Science.gov (United States)

    1975-01-01

    These vibration, acoustic, and shock specifications provide the qualification test criteria for spacecraft components and subassemblies and for the High Energy Astronomy Observatory (HEAO-A) experiments. The HEAO-A was divided into zones and subzones to obtain simple component groupings. Zones are designated primarily to assist in determining the applicable specification. A Subzone is available for use when the location of the component is known but component design and weight are not well defined. When the location, weight, and mounting configuration of the component are known, the appropriate Subzone weight ranges are available. Experiment and specific component specifications are available.

  19. Preliminary vibration, acoustic, and shock design and test criteria for components on the HEAO-C spacecraft

    Science.gov (United States)

    1975-01-01

    The vibration, acoustic, and shock specification test criteria for spacecraft components and subassemblies and for the high Energy Astronomy Observatory (HEAO-C) experiments are presented. The HEAO-C was divided into zones and subzones to obtain simple component groupings. Zones are designated primarily to assist in determining the applicable specification. A subzone (general specification) is available for use when the location of the component is known but component design and weight are not well defined. When the location, weight, and mounting configuration of the component are known, the appropriate subzone weight ranges (-A, -B, etc. ) are available. Experiment and specific component specifications are available.

  20. Online Continuous Flow Differential Electrochemical Mass Spectrometry with a Realistic Battery Setup for High-Precision, Long-Term Cycling Tests.

    Science.gov (United States)

    Berkes, Balázs B; Jozwiuk, Anna; Vračar, Miloš; Sommer, Heino; Brezesinski, Torsten; Janek, Jürgen

    2015-06-16

    We describe the benefits of an online continuous flow differential electrochemical mass spectrometry (DEMS) method that allows for realistic battery cycling conditions. We provide a detailed description on the buildup and the role of the different components in the system. Special emphasis is given on the cell design. The retention time and response characteristics of the system are tested with the electrolysis of Li2O2. Finally, we show a practical application in which a Li-ion battery is examined. The value of long-term DEMS measurements for the proper evaluation of electrolyte decomposition is demonstrated by an experiment where a Li(1+x)Ni(0.5)Mn(0.3)Co(0.2)O2 (NMC 532)/graphite cell is cycled over 20 charge/discharge cycles.

  1. New fixation set-up designed for micro-tensile test%新型试样固定装置在微拉伸测试中的应用

    Institute of Scientific and Technical Information of China (English)

    芦帅; 赵三军; 孙勇; 李鹏; 陈吉华

    2015-01-01

    目的:介绍一种新型的条状试样固定方式,应用于微拉伸测试粘接强度。方法:以临床常用牙科粘接剂 AdperTM Single Bond 2(SB2)制作树脂-牙本质粘接试件,切割成条状试样,随机分为2组进行微拉伸强度测试:Ciucchi's 夹具(对照组)和本试验装置(实验组),场发射扫描电镜观察试样断裂界面,卡方检验分析断裂模式;建立固定装置及夹具的三维有限元模型,计算机模拟分析拉伸试验中试样应力分布方式。结果:实验组与对照组的粘接强度(MPa)分别为32.76±7.43和43.58±4.72(P <0.05);实验组和对照组粘接界面混合断裂模式分别为28/36和20/36(P <0.05);有限元分析结果显示实验组在测试过程中拉伸力沿试样长轴传导,垂直粘接界面,断裂界面应力分布均匀。结论:该实验介绍的条状试样固定方法实用于微拉伸强度应力的测定。%Objective:To introduce a new fixation set-up for micro-tensile test.Methods:Dentin-composite were bonded with AdperTM Single Bond 2 (SB2)and sectioned into stick-shaped specimens.Specimens from each tooth(n =6)were equally divided into Ciucchi's jig and the designed set-up(Control and experimental)groups for micro-tensile bond test according to the utilized fixa-tion set-up.The bonding interface failure mode was examined with field-emission scanning electron microscope (FESEM).Three-dimensional models of the two set-ups and the specimen were developed,stress distribution was analyzed by finite element analysis (FEA).Results:The bond strength(MPa)of experimental and control group was 32.76 ±7.43 and 43.58 ±4.72(P <0.05),the ratio of mixed failure was 28 /36 and 20 /36(P <0.05)respectively.FEA showed that the designed set-up for fixing the sticks pro-vided a uniform stress distribution along the long axis of the specimen.FEA and failure mode analysis confirmed such uniform distri-bution was

  2. Acoustic and sonochemical methods for altering the viscosity of oil during recovery and pipeline transportation.

    Science.gov (United States)

    Abramov, Vladimir O; Abramova, Anna V; Bayazitov, Vadim M; Mullakaev, Marat S; Marnosov, Alexandr V; Ildiyakov, Alexandr V

    2017-03-01

    Reduction of oil viscosity is of great importance for the petroleum industry since it contributes a lot to the facilitation of pipeline transportation of oil. This study analyzes the capability of acoustic waves to decrease the viscosity of oil during its commercial production. Three types of equipment were tested: an ultrasonic emitter that is located directly in the well and affects oil during its production and two types of acoustic machines to be located at the wellhead and perform acoustic treatment after oil extraction: a setup for ultrasonic hydrodynamic treatment and a flow-through ultrasonic reactor. In our case, the two acoustic machines were rebuilt and tested in the laboratory. The viscosity of oil was measured before and after both types of acoustic treatment; and 2, 24 and 48h after ultrasonic treatment and 1 and 4h after hydrodynamic treatment in order to estimate the constancy of viscosity reduction. The viscosity reduction achieved by acoustic waves was compared to the viscosity reduction achieved by acoustic waves jointly with solvents. It was shown, that regardless of the form of powerful acoustic impact, a long lasting decrease in viscosity can be obtained only if sonochemical treatment is used. Using sonochemical treatment based on ultrasonic hydrodynamic treatment a viscosity reduction by 72,46% was achieved. However, the reduction in viscosity by 16%, which was demonstrated using the ultrasonic downhole tool in the well without addition of chemicals, is high enough to facilitate the production of viscous hydrocarbons.

  3. Monitoring of pipeline hydrostatic testing with artificial flaws applying acoustic emission and ultra-sonic techniques; Monitoracao de teste hidrostatico de tubos com descontinuidades artificiais empregando as tecnicas de emissao acustica e ultra-som

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Sergio Damasceno [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2003-07-01

    Charts and parameters used to perform and analyzing the acoustic emission data collected during the hydrostatic test in pipe samples build in API XL 60 with 20 inches of diameter and 14 millimeters of thickness are shown. These pipes had internal and external artificial flaws done by electro-erosion process with aspect ratio 1 x 20. A relationship between acoustic emission results, ultrasound and J-Integral were established using the applied pressurization sequence. Characteristics values of acoustic emission signals were shown as a criteria of field tests. (author)

  4. Algorithmic Pseudorandomness in Quantum Setups

    Science.gov (United States)

    Bendersky, Ariel; de la Torre, Gonzalo; Senno, Gabriel; Figueira, Santiago; Acín, Antonio

    2016-06-01

    Many experimental setups in quantum physics use pseudorandomness in places where the theory requires randomness. In this Letter we show that the use of pseudorandomness instead of proper randomness in quantum setups has potentially observable consequences. First, we present a new loophole for Bell-like experiments: if some of the parties choose their measurements pseudorandomly, then the computational resources of the local model have to be limited in order to have a proper observation of nonlocality. Second, we show that no amount of pseudorandomness is enough to produce a mixed state by computably choosing pure states from some basis.

  5. The spectral imaging facility: Setup characterization

    Energy Technology Data Exchange (ETDEWEB)

    De Angelis, Simone, E-mail: simone.deangelis@iaps.inaf.it; De Sanctis, Maria Cristina; Manzari, Paola Olga [Institute for Space Astrophysics and Planetology, INAF-IAPS, Via Fosso del Cavaliere, 100, 00133 Rome (Italy); Ammannito, Eleonora [Institute for Space Astrophysics and Planetology, INAF-IAPS, Via Fosso del Cavaliere, 100, 00133 Rome (Italy); Department of Earth, Planetary and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095-1567 (United States); Di Iorio, Tatiana [ENEA, UTMEA-TER, Rome (Italy); Liberati, Fabrizio [Opto Service SrL, Campagnano di Roma (RM) (Italy); Tarchi, Fabio; Dami, Michele; Olivieri, Monica; Pompei, Carlo [Selex ES, Campi Bisenzio (Italy); Mugnuolo, Raffaele [Italian Space Agency, ASI, Spatial Geodesy Center, Matera (Italy)

    2015-09-15

    The SPectral IMager (SPIM) facility is a laboratory visible infrared spectrometer developed to support space borne observations of rocky bodies of the solar system. Currently, this laboratory setup is used to support the DAWN mission, which is in its journey towards the asteroid 1-Ceres, and to support the 2018 Exo-Mars mission in the spectral investigation of the Martian subsurface. The main part of this setup is an imaging spectrometer that is a spare of the DAWN visible infrared spectrometer. The spectrometer has been assembled and calibrated at Selex ES and then installed in the facility developed at the INAF-IAPS laboratory in Rome. The goal of SPIM is to collect data to build spectral libraries for the interpretation of the space borne and in situ hyperspectral measurements of planetary materials. Given its very high spatial resolution combined with the imaging capability, this instrument can also help in the detailed study of minerals and rocks. In this paper, the instrument setup is first described, and then a series of test measurements, aimed to the characterization of the main subsystems, are reported. In particular, laboratory tests have been performed concerning (i) the radiation sources, (ii) the reference targets, and (iii) linearity of detector response; the instrumental imaging artifacts have also been investigated.

  6. Study of performance of acoustic fixture for using in noise reduction rate tests of hearing protection devices

    Directory of Open Access Journals (Sweden)

    zam Biabani

    2016-06-01

    Full Text Available Introduction:One of the recommended methods for evaluation effectiveness of hearing protection is use the acoustic fixture accordance with standard ISO 4869-3. The aim of this study was evaluate the acoustic performance of fixture for using in noise reduction rate tests of hearing protection devices in the laboratory. Methods: In this cross-sectional study , noise reduction rates of five common ear muffs used in the Iran industries were investigated based on the ISO 11904 standard, microphone in real ear method, using noise dosimeter (SVANTEK , Model SV102 equipped with microphone SV25 model which can install inside the ear on 30 subjects under laboratory conditions. Also, noise reduction rate of earmuffs was determined using the fixture model AVASINA9402 accordance with standard procedures. Data were analyzed using the software SPSS21. Results: The results showed the real noise reduction rates of the earmuffs on the studied subjects are from 59% to 94% nominal reduction rates. That rates for the ear muffs on the studied fixture are from 64% to 92.The results showed that the noise reduction rates of the ear muffs on subjects compared with and noise reduction rates of the ear muffs on fixture were not statistically significant (p> 0.05. Conclusion: The results showed the accuracy of noise reduction rate of earmuffs using the fixture compared with real subjects is acceptable. Hence, the fixture is good choice for environments where there’s no possibility of acoustic evaluation on real subjects, also for quality control of productions in the earmuff manufacturers.

  7. Development of modified vibration test criteria for qualifying space vehicle components. [subjected to broadband random acoustic excitation

    Science.gov (United States)

    Chang, K. Y.; Kao, G. C.

    1974-01-01

    Simplified methods are described to estimate the test criteria of primary structures at component attachment points subjected to broadband random acoustic excitations. The current method utilizes a constant smeared component mass attenuation factor across the frequency range of interest. The developed method indicates that the attenuation factor is based on a frequency dependent ratio of the mechanical impedances of both the component and primary structures. The procedures used to predict the structural responses are considered as the present state-of-the-art and provide satisfactory prediction results. Example problems are used to illustrate the application procedures of the two methods and to compare the significant difference. It was found that the lower test criteria obtained by the impedance ratio method is due to the results of considering the effects of component/primary structure interaction.

  8. Determination of Acoustic Effects on Marine Mammals and Sea Turtles for the Hawaii-Southern California Training and Testing Environmental Impact Statement/Overseas Environmental Impact Statement

    Science.gov (United States)

    2013-08-23

    Mammals and Sea Turtles for the Hawaii-Southern California Training and Testing Environmental Impact Statement/Overseas Environmental Impact...Effects on Marine Mammals and Sea Turtles for the Hawaii- Southern California Training and Testing Environmental Impact Statement/Overseas...program uses quantitative analysis methodology to estimate acoustic effects on designated marine fauna, which include marine mammals and sea turtles . This

  9. Determination of Acoustic Effects on Marine Mammals and Sea Turtles for the Atlantic Fleet Training and Testing Environmental Impact Statement/Overseas Environmental Impact Statement

    Science.gov (United States)

    2013-08-23

    Mammals and Sea Turtles for the Atlantic Fleet Training and Testing Environmental Impact Statement/Overseas Environmental Impact Statement...Mammals and Sea Turtles for the Atlantic Fleet Training and Testing Environmental Impact Statement/Overseas Environmental Impact Statement 5a...methodology to estimate acoustic effects on designated marine fauna, which include marine mammals and sea turtles . This report describes the process

  10. Analysis of acoustic-seismic coupling behaviour for CTBT on-site inspection performance improvement

    Energy Technology Data Exchange (ETDEWEB)

    Liebsch, Mattes; Knoop, Jan-Frederik [Technische Univ. Dortmund (Germany)

    2013-07-01

    After teleseismic detection of a big underground explosion, during on-site inspections under the Comprehensive Nuclear Test-Ban Treaty (CTBT) weak seismic signals from aftershocks are to be detected. These, however, can be masked by soil vibrations which are caused by acoustic waves which couple to the ground. To analyse the coupling behaviour between acoustic waves and soil vibrations several experiments with different acoustic sources (helicopters, firecrackers, loudspeaker) were performed. Of special interest is the influence of surface waves, excited in a larger area around the sensor, which can superpose constructively at the position of the sensor and can increase the measured seismic signal. A better understanding of the acoustic-seismic coupling can be used to develop guidelines for seismic aftershock measurements, such as a suitable sensor setup, with the goal of reducing or even preventing disturbing signals to improve the performance of on-site inspections for the CTBT.

  11. An experimental investigation of the generation and consequences of acoustic waves in an axial flow compressor Large axial spacings between blade rows

    Science.gov (United States)

    Parker, R.; Stoneman, S. A. T.

    1985-03-01

    The excitation of acoustic waves by vortex shedding from the inlet guide vanes in the annulus of a single-stage, low-speed axial-flow compressor test rig is investigated experimentally, in an effort to examine the assumptions made in the study of Parker (1984) and to provide data for mathematical models of these phenomena. The experimental setup and the transducers used to measure the operating and acoustic parameters are described in detail and illustrated with photographs and drawings, and the results are presented graphically. It is found that each mode excited can be associated with several excitation frequencies of the rotor blades, indicating forced blade vibration due to acoustic resonances.

  12. Acoustic detection of high energy neutrinos in sea water: status and prospects

    Science.gov (United States)

    Lahmann, Robert

    2017-03-01

    The acoustic neutrino detection technique is a promising approach for future large-scale detectors with the aim of measuring the small expected flux of neutrinos at energies in the EeV-range and above. The technique is based on the thermo-acoustic model, which implies that the energy deposition by a particle cascade - resulting from a neutrino interaction in a medium with suitable thermal and acoustic properties - leads to a local heating and a subsequent characteristic pressure pulse that propagates in the surrounding medium. Current or recent test setups for acoustic neutrino detection have either been add-ons to optical neutrino telescopes or have been using acoustic arrays built for other purposes, typically for military use. While these arrays have been too small to derive competitive limits on neutrino fluxes, they allowed for detailed studies of the experimental technique. With the advent of the research infrastructure KM3NeT in the Mediterranean Sea, new possibilities will arise for acoustic neutrino detection. In this article, results from the "first generation" of acoustic arrays will be summarized and implications for the future of acoustic neutrino detection will be discussed.

  13. Deformation, acoustic emission and ultrasound velocity during fatigue tests on paper

    Directory of Open Access Journals (Sweden)

    Hæggström E.

    2010-06-01

    Full Text Available We study the evolution of mechanical properties of paper samples during cyclic experiments. The issue is to look at the sample-to-sample variation, and we try to predict the number of loading cycles to failure. We used two concurrent methods to obtain the deformation: the strain was calculated from vertical displacement measured by laser interferometer sensor, as well as, computed by digital image correlation technique from pictures taken each 2s by a camera. Acoustic emission of fracture was also recorded, and an active ultrasonic wave method using piezoelectric transducers is used to follow the viscoelastic behaviour of each sample. We found that a sharp final increase of different variables like deformation, strain rate and fluctuations, are signs of an imminent rupture of the paper. Moreover looking at the evolution of these quantities during the first cycle only is already an indicator about the lifetime of the sample.

  14. Acoustical User Identification Based on MFCC Analysis of Keystrokes

    Directory of Open Access Journals (Sweden)

    Matus Pleva

    2015-01-01

    Full Text Available This paper introduces a novel approach of person identification using acoustical monitoring of typing the required word on the monitored keyboard. This experiment was motivated by the idea of COST IC1106 (Integrating Biometrics and Forensics for the Digital Age partners to acoustically analyse the captured keystroke dynamics database using widely used time-invariant mathematical models tools. The MFCC (Mel-Frequency Cepstral Coefficients and HMM (Hidden Markov Models was introduced in this experiment, which gives promising results of 99.33% accuracy, when testing 25% of realizations (randomly selected from 100 identifying between 50 users/models. The experiment was repeated for different training/testing configurations and cross-validated, so this first approach could be a good starting point for next research including feature selection algorithms, biometric authentication score normalization, different audio & keyboard setup tests, etc.

  15. Damage Characterization of Bio and Green Polyethylene–Birch Composites under Creep and Cyclic Testing with Multivariable Acoustic Emissions

    Directory of Open Access Journals (Sweden)

    Alencar Bravo

    2015-11-01

    Full Text Available Despite the knowledge gained in recent years regarding the use of acoustic emissions (AEs in ecologically friendly, natural fiber-reinforced composites (including certain composites with bio-sourced matrices, there is still a knowledge gap in the understanding of the difference in damage behavior between green and biocomposites. Thus, this article investigates the behavior of two comparable green and biocomposites with tests that better reflect real-life applications, i.e., load-unloading and creep testing, to determine the evolution of the damage process. Comparing the mechanical results with the AE, it can be concluded that the addition of a coupling agent (CA markedly reduced the ratio of AE damage to mechanical damage. CA had an extremely beneficial effect on green composites because the Kaiser effect was dominant during cyclic testing. During the creep tests, the use of a CA also avoided the transition to new damaging phases in both composites. The long-term applications of PE green material must be chosen carefully because bio and green composites with similar properties exhibited different damage processes in tests such as cycling and creep that could not be previously understood using only monotonic testing.

  16. Target spectrum matrix definition for multiple-input- multiple-output control strategies applied on direct-field- acoustic-excitation tests

    Science.gov (United States)

    Alvarez Blanco, M.; Janssens, K.; Bianciardi, F.

    2016-09-01

    During the last two decades there have been several improvements on environmental acoustic qualification testing for launch and space vehicles. Direct field excitation (DFAX) tests using Multiple-Input-Multiple-Output (MIMO) control strategies seems to become the most cost-efficient way for component and subsystem acoustic testing. However there are still some concerns about the uniformity and diffusivity of the acoustic field produced by direct field testing. Lately, much of the documented progresses aimed to solve the non-uniformity of the field by altering the sound pressure level requirement, limiting responses and adding or modifying control microphones positions. However, the first two solutions imply modifying the qualification criteria, which could lead to under-testing, potentially risking the mission. Furthermore, adding or moving control microphones prematurely changes the system configuration, even if it is an optimal geometric layout in terms of wave interference patterns control. This research investigates the target definition as an initial condition for the acoustic MIMO control. Through experiments it is shown that for a given system configuration the performance of a DFAX test strongly depends on the target definition procedure. As output of this research a set of descriptors are presented describing a phenomenon defined as “Energy- sink”.

  17. Extensions of cutting problems: setups

    Directory of Open Access Journals (Sweden)

    Sebastian Henn

    2013-08-01

    Full Text Available Even though the body of literature in the area of cutting and packing is growing rapidly, research seems to focus on standard problems in the first place, while practical aspects are less frequently dealt with. This is particularly true for setup processes which arise in industrial cutting processes whenever a new cutting pattern is started (i.e. a pattern is different from its predecessor and the cutting equipment has to be prepared in order to meet the technological requirements of the new pattern. Setups involve the consumption of resources and the loss of production time capacity. Therefore, consequences of this kind must explicitly be taken into account for the planning and control of industrial cutting processes. This results in extensions to traditional models which will be reviewed here. We show how setups can be represented in such models, and we report on the algorithms which have been suggested for the determination of solutions of the respective models. We discuss the value of these approaches and finally point out potential directions of future research.

  18. 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...

  19. Testing cosmic transparency with the latest baryon acoustic oscillations and type Ia supernovae data

    Institute of Scientific and Technical Information of China (English)

    Jun Chen; Pu-Xun Wu; Hong-Wei Yu; Zheng-Xiang Li

    2013-01-01

    Observations show that Type Ia supernovae (SNe Ia) are dimmer than expected from a matter dominated Universe.It has been suggested that this observed phenomenon can also be explained using light absorption instead of dark energy.However,there is a serious degeneracy between the cosmic absorption parameter and the present matter density parameter Ωm when one tries to place constraints on the cosmic opacity using SNe Ia data.We combine the latest baryon acoustic oscillation (BAO) and Union2 SNe Ia data in order to break this degeneracy.Assuming a flat ACDM model,we find that,although an opaque Universe is favored by SNe Ia+BAO since the best fit value of the cosmic absorption parameter is larger than zero,Ωm =1 is ruled out at the 99.7% confidence level.Thus,cosmic opacity is not sufficient to account for the present observations and dark energy or modified gravity is still required.

  20. An automated full-chip micro-piv setup for measuring microchannel acoustophoresis:

    DEFF Research Database (Denmark)

    Barnkob, Rune; Augustsson, P.; Laurell, T.

    2011-01-01

    We present a novel μm-resolution particle-image velocimetry setup capable of automated full-chip measurements of microchannel acoustophoresis. Our system allows for fast collection of a sufficient amount of data enabling reliable determination of the influence from the forces from acoustic radiat...

  1. Acoustic sensor engineering evaluation test report. [microphones for monitoring inside the space shuttle orbiter

    Science.gov (United States)

    Phillips, E. L., Jr.; Bronson, R. D.

    1976-01-01

    Two types of one-inch diameter sound pressure level sensors, which are candidates for monitoring ambient noise in the shuttle orbiter crew compartment during rest periods, were exposed to temperature, passive humidity, and vibration. One unexposed sensor of each type served as a reference unit. Except for the humidity exposures, each of the three capacitive microphones was individually tested in sequence with the essential voltage power supply and preamplifier. One unit exibited anomalous characteristics after the humidity exposure but returned to normal after being dried in an oven at 115 deg for two hours. Except for the humidity exposures, each of the three piezoelectric microphones was individually tested with a laboratory type amplifier. Two apparent failures occurred during these tests. The diaphragm on one was found ruptured after the fourth cycle of the humidity test. A second sensor showed an anomaly after the random vibration tests at which time its sensitivity was consistent at about one-half its former value.

  2. Acoustic reconstruction of the velocity field in a furnace using a characteristic flow model.

    Science.gov (United States)

    Li, Yanqin; Zhou, Huaichun; Chen, Shiying; Zhang, Yindi; Wei, Xinli; Zhao, Jinhui

    2012-06-01

    An acoustic method can provide a noninvasive, efficient and full-field reconstruction of aerodynamic fields in a furnace. A simple yet reasonable model is devised for reconstruction of a velocity field in a cross section of a tangential furnace from acoustic measurements based on typical physical characteristics of the field. The solenoidal component of the velocity field is modeled by a curved surface, derived by rotating a curve of Gaussian distribution, determined by six characteristic parameters, while the nonrotational component is governed by a priori knowledge. Thus the inverse problem is translated into determination of the characteristic parameters using a set of acoustic projection data. First numerical experiments were undertaken to simulate the acoustic measurement, so as to preliminarily validate the effectiveness of the model. Based on this, physical experiments under different operating conditions were performed in a pilot-scale setup to provide a further test. Hot-wire anemometry and strip floating were applied to compare with acoustic measurements. The acoustic measurements provided satisfactory consistency with both of these approaches. Nevertheless, for a field with a relatively large magnitude of air velocities, the acoustic measurement can give more reliable reconstructions. Extension of the model to measurements of hot tangential furnaces is also discussed.

  3. Setup Analysis: Combining SMED with Other Tools

    Directory of Open Access Journals (Sweden)

    Stadnicka Dorota

    2015-02-01

    Full Text Available The purpose of this paper is to propose the methodology for the setup analysis, which can be implemented mainly in small and medium enterprises which are not convinced to implement the setups development. The methodology was developed after the research which determined the problem. Companies still have difficulties with a long setup time. Many of them do nothing to decrease this time. A long setup is not a sufficient reason for companies to undertake any actions towards the setup time reduction. To encourage companies to implement SMED it is essential to make some analyses of changeovers in order to discover problems. The methodology proposed can really encourage the management to take a decision about the SMED implementation, and that was verified in a production company. The setup analysis methodology is made up of seven steps. Four of them concern a setups analysis in a chosen area of a company, such as a work stand which is a bottleneck with many setups. The goal is to convince the management to begin actions concerning the setups improvement. The last three steps are related to a certain setup and, there, the goal is to reduce a setup time and the risk of problems which can appear during the setup. In this paper, the tools such as SMED, Pareto analysis, statistical analysis, FMEA and other were used.

  4. Split Hopkinson resonant bar test for sonic-frequency acoustic velocity and attenuation measurements of small, isotropic geological samples

    Science.gov (United States)

    Nakagawa, Seiji

    2011-04-01

    Mechanical properties (seismic velocities and attenuation) of geological materials are often frequency dependent, which necessitates measurements of the properties at frequencies relevant to a problem at hand. Conventional acoustic resonant bar tests allow measuring seismic properties of rocks and sediments at sonic frequencies (several kilohertz) that are close to the frequencies employed for geophysical exploration of oil and gas resources. However, the tests require a long, slender sample, which is often difficult to obtain from the deep subsurface or from weak and fractured geological formations. In this paper, an alternative measurement technique to conventional resonant bar tests is presented. This technique uses only a small, jacketed rock or sediment core sample mediating a pair of long, metal extension bars with attached seismic source and receiver—the same geometry as the split Hopkinson pressure bar test for large-strain, dynamic impact experiments. Because of the length and mass added to the sample, the resonance frequency of the entire system can be lowered significantly, compared to the sample alone. The experiment can be conducted under elevated confining pressures up to tens of MPa and temperatures above 100 °C, and concurrently with x-ray CT imaging. The described split Hopkinson resonant bar test is applied in two steps. First, extension and torsion-mode resonance frequencies and attenuation of the entire system are measured. Next, numerical inversions for the complex Young's and shear moduli of the sample are performed. One particularly important step is the correction of the inverted Young's moduli for the effect of sample-rod interfaces. Examples of the application are given for homogeneous, isotropic polymer samples, and a natural rock sample.

  5. Split Hopkinson Resonant Bar Test for Sonic-Frequency Acoustic Velocity and Attenuation Measurements of Small, Isotropic Geologic Samples

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, S.

    2011-04-01

    Mechanical properties (seismic velocities and attenuation) of geological materials are often frequency dependent, which necessitates measurements of the properties at frequencies relevant to a problem at hand. Conventional acoustic resonant bar tests allow measuring seismic properties of rocks and sediments at sonic frequencies (several kilohertz) that are close to the frequencies employed for geophysical exploration of oil and gas resources. However, the tests require a long, slender sample, which is often difficult to obtain from the deep subsurface or from weak and fractured geological formations. In this paper, an alternative measurement technique to conventional resonant bar tests is presented. This technique uses only a small, jacketed rock or sediment core sample mediating a pair of long, metal extension bars with attached seismic source and receiver - the same geometry as the split Hopkinson pressure bar test for large-strain, dynamic impact experiments. Because of the length and mass added to the sample, the resonance frequency of the entire system can be lowered significantly, compared to the sample alone. The experiment can be conducted under elevated confining pressures up to tens of MPa and temperatures above 100 C, and concurrently with x-ray CT imaging. The described Split Hopkinson Resonant Bar (SHRB) test is applied in two steps. First, extension and torsion-mode resonance frequencies and attenuation of the entire system are measured. Next, numerical inversions for the complex Young's and shear moduli of the sample are performed. One particularly important step is the correction of the inverted Young's moduli for the effect of sample-rod interfaces. Examples of the application are given for homogeneous, isotropic polymer samples and a natural rock sample.

  6. Advanced Jet Noise Exhaust Concepts in NASA's N+2 Supersonics Validation Study and the Environmentally Responsible Aviation Project's Upcoming Hybrid Wing Body Acoustics Test

    Science.gov (United States)

    Henderson, Brenda S.; Doty, Mike

    2012-01-01

    Acoustic and flow-field experiments were conducted on exhaust concepts for the next generation supersonic, commercial aircraft. The concepts were developed by Lockheed Martin (LM), Rolls-Royce Liberty Works (RRLW), and General Electric Global Research (GEGR) as part of an N+2 (next generation forward) aircraft system study initiated by the Supersonics Project in NASA s Fundamental Aeronautics Program. The experiments were conducted in the Aero-Acoustic Propulsion Laboratory at the NASA Glenn Research Center. The exhaust concepts presented here utilized lobed-mixers and ejectors. A powered third-stream was implemented to improve ejector acoustic performance. One concept was found to produce stagnant flow within the ejector and the other produced discrete-frequency tones (due to flow separations within the model) that degraded the acoustic performance of the exhaust concept. NASA's Environmentally Responsible Aviation (ERA) Project has been investigating a Hybrid Wing Body (HWB) aircraft as a possible configuration for meeting N+2 system level goals for noise, emissions, and fuel burn. A recently completed NRA led by Boeing Research and Technology resulted in a full-scale aircraft design and wind tunnel model. This model will be tested acoustically in NASA Langley's 14-by 22-Foot Subsonic Tunnel and will include dual jet engine simulators and broadband engine noise simulators as part of the test campaign. The objectives of the test are to characterize the system level noise, quantify the effects of shielding, and generate a valuable database for prediction method development. Further details of the test and various component preparations are described.

  7. A centrifugally actuated point-of-care testing system for the surface acoustic wave immunosensing of cardiac troponin I.

    Science.gov (United States)

    Lee, Woochang; Jung, Jaeyeon; Hahn, Young Ki; Kim, Sang Kyu; Lee, Yeolho; Lee, Joonhyung; Lee, Tae-Han; Park, Jin-Young; Seo, Hyejung; Lee, Jung Nam; Oh, Jin Ho; Choi, Youn-Suk; Lee, Soo Suk

    2013-05-07

    A fully automated point-of-care testing (POCT) system with a surface acoustic wave (SAW) immunosensor was developed for rapid and sensitive detection of cardiac troponin I (cTnI) in body fluid (plasma and whole blood). The assay, based on gold nanoparticle sandwich immunoassay and subsequent gold staining, was performed on the SAW immunosensor packaged inside a disposable microfluidic cartridge. The entire fluidic process, including plasma separation, reagent transport, metering, and mixing, was carried out by controlling the centrifugal force acting on the rotating cartridge and laser-irradiated ferrowax microvalves. On investigation of sensor response to various cTnI concentrations, the system exhibited a high performance with a detection limit of 6.7 pg mL(-1), and the coefficient of variation was less than 10% over the entire test range (10 pg mL(-1) to 25 ng mL(-1)). On comparing this POCT system with a clinically utilized system in a physical laboratory (Centaur® XP; Siemens), a correlation coefficient of 0.998 was found, validating the diagnostic capability of the SAW immunosensor.

  8. Azimuthal cement evaluation with an acoustic phased-arc array transmitter:numerical simulations andfi eld tests

    Institute of Scientific and Technical Information of China (English)

    Che Xiao-Hua; Qiao Wen-Xiao; Ju Xiao-Dong; Wang Rui-Jia

    2016-01-01

    We developed a novel cement evaluation logging tool, named the azimuthally acoustic bond tool (AABT), which uses a phased-arc array transmitter with azimuthal detection capability. We combined numerical simulations andfi eld tests to verify the AABT tool. The numerical simulation results showed that the radiation direction of the subarray corresponding to the maximum amplitude of the first arrival matches the azimuth of the channeling when it is behind the casing. With larger channeling size in the circumferential direction, the amplitude difference of the casing wave at different azimuths becomes more evident. The test results showed that the AABT can accurately locate the casing collars and evaluate the cement bond quality with azimuthal resolution at the casing–cement interface, and can visualize the size, depth, and azimuth of channeling. In the case of good casing–cement bonding, the AABT can further evaluate the cement bond quality at the cement–formation interface with azimuthal resolution by using the amplitude map and the velocity of the formation wave.

  9. 对MRI系统噪声的法规要求及测试方法%Regulatory Requirements and Testing Methods of MRI Acoustic Noise

    Institute of Scientific and Technical Information of China (English)

    薛廷强; 裴茂增; 何超明

    2014-01-01

    MRI扫描过程中梯度线圈受变化的洛伦茨力作用会产生振动并发出噪声。过高的噪声除了会引起病人不适外,还可能影响成像效果。本文总结并分析了MRI噪声相关的法规要求及相应测试方法,旨在为相关人员客观评估MRI系统的声学噪声特性,确保系统安全,测试相应降噪措施提供参考。%Gradient coil which is subjected to a variational Lorentz force during MRI scanning can cause gradient coil vibration and then produce acoustic noise. Exorbitant acoustic noise can cause discomfort for patients, and also can affect imaging quality. This paper summarized and analyzed the regulatory requirements and corresponding testing methods of MRI acoustic noise in order to provide reference information for relevant staff to objectively evaluate acoustic noise features of MRI system to ensure system safety and test noise reduction measures.

  10. Desktop setup for binary holograms

    Science.gov (United States)

    Ginter, Olaf; Rothe, Hendrik

    1996-08-01

    Binary gratings as holograms itself or as photographic masking tools for further fabrication steps can fulfill a lot of applications. The commonly used semiconductor technologies for direct writing of high resolution structures are often too expensive. On the other hand computer plots at a reasonable price with photographic reduction do not meet the needs of precision e.g. for interferometric inspection. The lack of cheap and reliable instruments for direct writing in an appropriate resolution is still a problem in fabricating synthetic holograms. Using off-the-shelf components a direct writing plotter for binary patterns can be built at moderate costs. Typical design rules as well as experimental results are given and the final setup is introduced.

  11. Monitoring of the production quality of fibre-reinforced pressure vessels using acoustic emission testing; Ueberwachung der Fertigungsqualitaet von Faserverbund-Druckbehaeltern mittels Schallemissionspruefung

    Energy Technology Data Exchange (ETDEWEB)

    Duffner, Eric; Gregor, Christian; Bohse, Juergen [BAM Bundesanstalt fuer Materialforschung und -pruefung, Berlin (Germany)

    2011-07-01

    The investigation aimed at the validation of a test method for ensuring the production quality of reinforced-fibre pressure vessels in real fabrication conditions. The method is based on characteristics and permissible limiting values derived from acoustic emission curves during the first pressure test. The method had already been tested successfully on reinforced-fibre pressure vessels with metal liners and had been patented. With the current investigations, the possibility of detection fabrication defects in carbon fibre / glass fibre hybrid pressure vessels with polymer liners was evaluated. For this, fibre-reinforced pressure vessels were monitored by acoustic emission measurement during the first hydraulic pressure test; this test is commonly used for quality assurance of this type of pressure vessel, although without acoustic emission testing. Acoustic emission curves were registered for pressure vessels of a serial production, and the mean characteristics and their scatter were determined as reference values. These were compared with the acoustic emission curves of selectively induced fabrication defects. Fabrication defects are defects that may occur in serial production and are difficult or impossible to detect by conventional quality assurance methods. All investigated pressure vessel were then subject to stress until failure (leakage, bursting). This made it possible to verify the real influence of fabrication defects on the burst pressure and/or the fatigue characteristics of the pressure vessels and to assess the validity of acoustic emission testing. [German] Ziel der Untersuchung ist die Validierung einer Pruefmethodik zur Sicherung der Fertigungsqualitaet von Faserverbund - Druckbehaeltern unter realen Fertigungsbedingungen. Das Verfahren basiert auf Merkmalen und zulaessigen Grenzwerten, die aus Schallemissionsverlaeufen bei der Erstdruckpruefung abgeleitet werden [1]. Die Methodik konnte zuvor bereits erfolgreich an Faserverbund - Druckbehaeltern

  12. 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....

  13. Rician Channel Modeling for Multiprobe Anechoic Chamber Setups

    DEFF Research Database (Denmark)

    Fan, Wei; Kyösti, Pekka; Hentilä, Lassi;

    2014-01-01

    This paper discusses over the air (OTA) testing for multiple input multiple output (MIMO) capable terminals, with emphasis on modeling Rician channel models in the multi-probe anechoic chamber setups. A technique to model Rician channels is proposed. The line-of-sight (LOS) component, with an arb......This paper discusses over the air (OTA) testing for multiple input multiple output (MIMO) capable terminals, with emphasis on modeling Rician channel models in the multi-probe anechoic chamber setups. A technique to model Rician channels is proposed. The line-of-sight (LOS) component...

  14. Verification of nonlinear dynamic structural test results by combined image processing and acoustic analysis

    Science.gov (United States)

    Tene, Yair; Tene, Noam; Tene, G.

    1993-08-01

    An interactive data fusion methodology of video, audio, and nonlinear structural dynamic analysis for potential application in forensic engineering is presented. The methodology was developed and successfully demonstrated in the analysis of heavy transportable bridge collapse during preparation for testing. Multiple bridge elements failures were identified after the collapse, including fracture, cracks and rupture of high performance structural materials. Videotape recording by hand held camcorder was the only source of information about the collapse sequence. The interactive data fusion methodology resulted in extracting relevant information form the videotape and from dynamic nonlinear structural analysis, leading to full account of the sequence of events during the bridge collapse.

  15. The Acoustic Results of a United Technologies Scale Model Helicopter Rotor Tested at DNW

    Science.gov (United States)

    1990-05-01

    Annual Forum of the Amer- Germany (Refs. 3,4). It was this ’ benchmark ’ test ican Helicopter Society, Washington, DC May 1990 which led to the...The au- 2. Schmitz, F.H., Boxwell , DA., Lewy, S., and Da- thors would like to offer sincere thanks to their friends han, C., "A Note on the Generel...W.R., Schultz, K.J., Schmitz, F.H., ing for their contributions made in acquiring the data and Boxwell ,D.A.,"Model Rotor High Speed Im- presented in

  16. Resizing buffer rods for ultrasound testing of food products with acoustic noise considerations.

    Science.gov (United States)

    García-Álvarez, Javier; García-Hernández, Miguel J; Novoa-Díaz, Daniel F; Turó Peroy, Antoni; Chávez Domínguez, Juan Antonio; Salazar Soler, Jordi

    2013-01-01

    Buffer rods can be used to perform non-destructive and on-line analysis of food and beverage products. These rods, usually solid cylinders, can be long and heavy for certain applications. In this paper, a resizing analytic procedure is described. Buffer rods designed following this new procedure can be several times shorter than the conventionally designed ones, optimising thus their weight and cost. The signal to noise ratio (SNR) of the resized buffers is also studied in order to determine their practical usability. To this effect, simulations and experiments are conducted using metal and plastic buffer rod materials appropriate for food and beverage testing such as aluminium and polyethylene.

  17. 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...

  18. Audience effects, but not environmental influences, explain variation in gorilla close distance vocalizations-A test of the acoustic adaptation hypothesis.

    Science.gov (United States)

    Hedwig, Daniela; Mundry, Roger; Robbins, Martha M; Boesch, Christophe

    2015-12-01

    Close distance vocalizations are an integral part of primate vocal communication. They exhibit large acoustic variation which has been suggested to constitute flexible responses to the highly variable social setting of group living animals. However, a recent study suggested that acoustic variation in close distance calls of baboons may also arise from acoustic adaptations to environmental factors in order to counteract sound degradation. We tested whether the variation in calling rate and acoustic structure of gorilla close distance vocalizations may serve to counteract distorting effects of vegetation during sound propagation. Using focal animal sampling we recorded the vocal behavior of 15 adult individuals living in two groups: one group of western lowland gorillas Gorilla gorilla gorilla and one group of mountain gorillas Gorilla beringei beringei. We considered the distance between the caller and its nearest neighbor as the minimum transmission distance of calls; while vegetation density was quantified through measures of visibility. Our analysis revealed vocal plasticity in gorilla close calls in relation to changes in visibility and nearest neighbor distance. However, the observed changes in fundamental frequency and calling rate are unlikely to counteract degrading effects of vegetation, but rather seem to reflect reactions to variation in spatial and visual separation from other group members, similar to the audience effects demonstrated in a range of other species. We propose that vocal plasticity to counteract distorting environmental effects may not be prevalent across taxa and perhaps confined to species living in heterogeneous habitats with highly variable transmission conditions.

  19. Acoustic levitation of a large solid sphere

    Science.gov (United States)

    Andrade, Marco A. B.; Bernassau, Anne L.; Adamowski, Julio C.

    2016-07-01

    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.

  20. Preparation and evaluation of orthodontic setup

    OpenAIRE

    Telma Martins de Araújo; Lílian Martins Fonseca; Luciana Duarte Caldas; Roberto Amarante Costa-Pinto

    2012-01-01

    INTRODUCTION: An orthodontic or diagnostic setup consists in cutting and realigning the teeth in plaster models, making it an important resource in orthodontic treatment planning. OBJECTIVE: The aim of this article is to provide a detailed description of a technique to build an orthodontic setup model and a method to evaluate it. CONCLUSIONS: Although laborious, orthodontic setup procedure and analysis can provide important information such as the need for dental extractions, interproximal st...

  1. Preparation and evaluation of orthodontic setup

    Directory of Open Access Journals (Sweden)

    Telma Martins de Araújo

    2012-06-01

    Full Text Available INTRODUCTION: An orthodontic or diagnostic setup consists in cutting and realigning the teeth in plaster models, making it an important resource in orthodontic treatment planning. OBJECTIVE: The aim of this article is to provide a detailed description of a technique to build an orthodontic setup model and a method to evaluate it. CONCLUSIONS: Although laborious, orthodontic setup procedure and analysis can provide important information such as the need for dental extractions, interproximal stripping, anchorage system, among others.

  2. Preparation and evaluation of orthodontic setup

    OpenAIRE

    Araújo, Telma Martins de; Fonseca, Lílian Martins; Caldas, Luciana Duarte; Pinto, Roberto Amarante Costa

    2012-01-01

    p. 146-165 Introduction: An orthodontic or diagnostic setup consists in cutting and realigning the teeth in plaster models, making it an important resource in orthodontic treatment planning. Objetive: The aim of this article is to provide a detailed description of a technique to build an orthodontic setup model and a method to evaluate it. Conclusions: Although laborious, orthodontic setup procedure and analysis can provide important information such as the need for dental extractions, ...

  3. Theoretical analyses and numerical simulations of the torsional mode for two acoustic viscometers with preliminary experimental tests.

    Science.gov (United States)

    Ai, Yuhui; Lange, Rebecca A

    2008-03-01

    A rigorous analysis of the torsional modes in both a cylindrical wave guide and the associated static viscous fluid field has been conducted from the solid and the fluid wave equations and the coupled boundary conditions. As a result, two acoustic viscometer models, along with four independent equations connecting the density and the viscosity of the fluid with the attenuation and the phase velocity of the torsional wave in the wave guide, have been developed. The analysis shows that the product of the viscosity and the density of the fluid can be measured from the end reflection coefficient of the torsional wave in the wave guide and that both the viscosity and the density can be determined simultaneously from either the phase velocity or the attenuation of the torsional wave in a single cylindrical wave guide. For the simultaneous measurements of the viscosity and the density, the independent equations have to be solved numerically, for example, using Matlab (The MathWorks, Natick, MA), given either the attenuation or the phase velocity in the wave guide that is surrounded by the fluid. To demonstrate the technical feasibility, numerical simulations have been conducted to discern viscosity, phase velocity, and density, all versus attenuation, at different frequencies, and with variable dimension of a molybdenum rod, so that both the advantages and the disadvantages of the simultaneous measurements can be explored. In the end, to test the two models, preliminary experiments on two viscous standards were conducted at 23 degrees C, and good agreements have been achieved between the viscosities measured from both models and for both standards.

  4. Set-up for lifetime measurements with the DSA method

    Energy Technology Data Exchange (ETDEWEB)

    Avrigeanu, V.; Bucurescu, D.; Ivascu, M.; Osvath, E.; Popescu, D.; Stog, O.

    1975-01-01

    A set-up for the measurement of short nuclear lifetimes at the IAP U-120 cyclotron, by means of the Doppler shift attenuation method (DSAM) is described. A 100 mm diameter reaction chamber is used, with a transparent window which allows visualization of the beam spot on the target. The electronic block scheme is discussed. As a test measurement for this set-up the determination of the lifetime of the first 2/sup +/ state in /sup 30/Si by means of the /sup 27/Al(..cap alpha..,p..gamma..)/sup 30/Si reaction is presented. 5 figures.

  5. Acoustic resonance spectroscopy for the advanced undergraduate laboratory

    CERN Document Server

    Franco-Villafañe, J A; Báez, G; Gandarilla-Carrillo, O; Méndez-Sánchez, R A

    2013-01-01

    We present a simple experiment that allows advanced undergraduates to learn the principles and applications of spectroscopy. The technique, known as acoustic resonance spectroscopy, is applied to study a vibrating rod. The setup includes electromagnetic-acoustic transducers, an audio amplifier and a vector network analyzer. Typical results of compressional, torsional and bending waves are analyzed and compared with analytical results.

  6. Acoustic resonance spectroscopy for the advanced undergraduate laboratory

    Science.gov (United States)

    Franco-Villafañe, J. A.; Flores-Olmedo, E.; Báez, G.; Gandarilla-Carrillo, O.; Méndez-Sánchez, R. A.

    2012-11-01

    We present a simple experiment that allows advanced undergraduates to learn the principles and applications of spectroscopy. The technique, known as acoustic resonance spectroscopy, is applied to study a vibrating rod. The setup includes electromagnetic-acoustic transducers, an audio amplifier and a vector network analyzer. Typical results of compressional, torsional and bending waves are analyzed and compared with analytical results.

  7. Developments and field tests of low-frequency portable acoustic transducers for a mobile exploration and time lapse experiment of a sea-bottom reservoir

    Science.gov (United States)

    Tsuruga, K.; Kasahara, J.; Hasada, Y.; Kondo, H.

    2013-12-01

    Depth, scale and resolutions of geophysical explorations for mineral resources are controlled by transmitted seismic energy and wavelength (frequency range). Most explorations in marine have been conducted by survey ship system with arrayed acoustic sources whose dominant frequency range is about 10 to 500 Hz. On the other hand, for shallow parts of sea bottom structure survey, some sub-bottom profilers with frequency range around 3.5kHz are used. To monitor a time lapse of a sea bottom reservoir such as an oil, gas, or methane hydrate reservoir as well as to exploit a mobile survey near a sea bottom by AUVs, it is necessary to use a broadband portable acoustic transducer with a dominant frequency range of 500 Hz to 5 kHz. We have been developing several types of portable acoustic transducers and a transmitting and recording system which is accurately controlled by a GPS clock (Tsuruga et al., 2012). In this pater, we report the new broadband acoustic portable transducers which have larger power than the original cylindrical acoustic transducers in a low frequency range (tests at the shallow sea bottom around 32 m deep by means of the transducers and hydrophone receivers array. Each transducer repeatedly transmitted Chirp signals with a unit period of 500 msec in two frequency ranges of 0.5k-4.5kHz and 4k-16kHz . We stacked 500-ms data by 28 times to obtain a transfer function of each source-receiver pair in the time and frequency domains. The preliminary results suggest as the follows: (i) it is successful to broaden the frequency bandwidth (i.e., 2k-10kHz) by extending a geometrical resonance length of a cylindrical acoustic transducers, and (ii) the observation at the sea bottom with accurately controlled timing systems of transmitter and data-logger is very useful to identify the stable and/or unstable seismic phases, that is, waves propagating in a underground and/or in a sea water as well as to reduce random noises caused by ocean waves over the data. In

  8. Acoustic streaming jets: A scaling and dimensional analysis

    Science.gov (United States)

    Botton, V.; Moudjed, B.; Henry, D.; Millet, S.; Ben-Hadid, H.; Garandet, J. P.

    2015-10-01

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

  9. Acoustic streaming jets: A scaling and dimensional analysis

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-10-28

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

  10. Android Virtual Machine (VM) Setup on Linux

    Science.gov (United States)

    2014-12-01

    Machine (VM) Setup on Linux Ken F Yu Computational and Information Sciences Directorate, ARL...Virtual Machine (VM) Setup on Linux 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Ken F Yu 5d. PROJECT NUMBER

  11. A setup for active fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2006-01-01

    A setup for active fault diagnosis (AFD) of parametric faults in dynamic systems is formulated in this paper. It is shown that it is possible to use the same setup for both open loop systems, closed loop systems based on a nominal feedback controller as well as for closed loop systems based...

  12. New Measuring Temperature Setup with Optical Probe①

    Institute of Scientific and Technical Information of China (English)

    HOUPeiguo; LIUJianming

    1997-01-01

    A new setup of measuring temperature is developed,which the probe is a micro-power consumptive one with CMOS circuit and is driven by optical power.For transmitting the measured signal and optical signal in a long distance,the fiber technology is applied in this setup.

  13. An Investigation of the Effects of Metallurgical and/or Testing Variables on the Acoustic Emission from Crystalline Materials.

    Science.gov (United States)

    1982-09-01

    precipitate strengths. For easy cross slip systems, ACOUSTIC EMISSION including 7075 aluminium , 6061 aluminium , 2219 It is unlikely that the motion of a...peak was observed in JBK-75 and Noise was subtracted from the measured rms acoustic 6061 aluminium , but not in KHB or 7075 aluminium . Small emission...and100-150 A thick. The formation of0’ results in softening of the alloy. Above - 275°C 0’ is converted into heights for JBK-75 and 6061 aluminium as

  14. Acoustic mapping velocimetry

    Science.gov (United States)

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

    2016-05-01

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

  15. The Acoustic Emission signal acquired by the microphones placed in the CABRI test device along the fourteen last R.I.A. experiments: an example of reproducible research in nuclear science

    Energy Technology Data Exchange (ETDEWEB)

    Laurent Pantera, Oumar Traore [CEA, DEN, DER/SRES, Cadarache, F-13108 Saint Paul lez Durance (France)

    2015-07-01

    , analyses and graphics representations were not straightforward to reproduce from the ancient studies since that, on one hand, people who were in charge of the original work left the laboratory and on the other hand because it is not easy when the time passes, even with our own work, to be able to remember the steps of data manipulations and the exact setup: - During the ancient experiments the use of analog data acquisition systems required to digitize tapes to be able to realize computer treatments. That had had for consequence to lose the initial dating. This one must be correctly edited to do temporal comparisons. - Analyses require functions for calculations whose parameters has to be well-known to reach the same results. We thus wished to manage our workflow in the idea that it can be easily reproducible on all the experiments. The object of the work presented in this article was to put in practice this strong bind between the data, treatments and generation of the document in order not to hesitate to do the iteration principle in action. We do not have to be afraid by the data driven analyses. According to the philosophy of the literate programming, the text of the technical document is woven with the computer code that produces all the printed output as tables, graphs for the study eliminating hence the unrealistic cut and paste. This difficulty is not specific to the nuclear domain. For many years, researchers have been worked out solutions to this mundane issue. And, presently, new technologies and high-level programming languages offer us actual answers. We will firstly present the tools applied in our laboratory to implement this workflow, then we will describe the global perception carried out to continue the study of the Acoustic Emission signals recorded by the two microphones during the fourteen last CABRI R.I.A. test.

  16. Electroacoustical simulation of listening room acoustics for project ARCHIMEDES

    DEFF Research Database (Denmark)

    Bech, Søren

    1989-01-01

    ARCHIMEDES is a psychoacoustics research project, funded under the European EUREKA scheme. Three partners share the work involved: The Acoustics Laboratory of The Technical University of Denmark; Bang and Olufsen of Denmark; and KEF Electronics of England. Its primary object is to quantify...... the influence of listening room acoustics on the timbre of reproduced sound. For simulation of the acoustics of a standard listening room, an electroacoustic setup has been built in an anechoic chamber. The setup is based on a computer model of the listening room, and it consists of a number of loudspeakers...

  17. 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

  18. 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.

  19. Acoustic biosensors

    OpenAIRE

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

    2016-01-01

    Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of ...

  20. Characterization of a neutron imaging setup at the INES facility

    Energy Technology Data Exchange (ETDEWEB)

    Durisi, E.A., E-mail: elisabettaalessandra.durisi@unito.it [Università di Torino, Dipartimento di Fisica, Via Pietro Giuria 1, 10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare—Sezione di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Visca, L. [Università di Torino, Dipartimento di Fisica, Via Pietro Giuria 1, 10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare—Sezione di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Albertin, F.; Brancaccio, R. [Istituto Nazionale di Fisica Nucleare—Sezione di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Corsi, J. [Università di Torino, Dipartimento di Fisica, Via Pietro Giuria 1, 10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare—Sezione di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Dughera, G. [Istituto Nazionale di Fisica Nucleare—Sezione di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Ferrarese, W. [Università di Torino, Dipartimento di Fisica, Via Pietro Giuria 1, 10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare—Sezione di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Giovagnoli, A.; Grassi, N. [Fondazione Centro per la Conservazione ed il Restauro dei Beni Culturali “La Venaria Reale”, Piazza della Repubblica, 10078 Venaria Reale, Torino (Italy); Grazzi, F. [Consiglio Nazionale delle Ricerche, Istituto dei Sistemi Complessi, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze (Italy); Lo Giudice, A.; Mila, G. [Università di Torino, Dipartimento di Fisica, Via Pietro Giuria 1, 10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare—Sezione di Torino, Via Pietro Giuria 1, 10125 Torino (Italy); and others

    2013-10-21

    The Italian Neutron Experimental Station (INES) located at the ISIS pulsed neutron source (Didcot, United Kingdom) provides a thermal neutron beam mainly used for diffraction analysis. A neutron transmission imaging system was also developed for beam monitoring and for aligning the sample under investigation. Although the time-of-flight neutron diffraction is a consolidated technique, the neutron imaging setup is not yet completely characterized and optimized. In this paper the performance for neutron radiography and tomography at INES of two scintillator screens read out by two different commercial CCD cameras is compared in terms of linearity, signal-to-noise ratio, effective dynamic range and spatial resolution. In addition, the results of neutron radiographies and a tomography of metal alloy test structures are presented to better characterize the INES imaging capabilities of metal artifacts in the cultural heritage field. -- Highlights: A full characterization of the present INES imaging set-up was carried out. Two CCD cameras and two scintillators (ZnS/{sup 6}LiF) of different thicknesses were tested. Linearity, effective dynamic range and spatial resolution were determined. Radiographies of steep wedges were performed using the highest dynamic range setup. Tomography of a bronze cube was performed using the best spatial resolution setup.

  1. Photothermal excitation setup for a modified commercial atomic force microscope

    Energy Technology Data Exchange (ETDEWEB)

    Adam, Holger; Rode, Sebastian; Schreiber, Martin; Kühnle, Angelika, E-mail: kuehnle@uni-mainz.de [Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55099 Mainz (Germany); Kobayashi, Kei; Yamada, Hirofumi [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan)

    2014-02-15

    High-resolution imaging in liquids using frequency modulation atomic force microscopy is known to suffer from additional peaks in the resonance spectrum that are unrelated to the cantilever resonance. These unwanted peaks are caused by acoustic modes of the liquid and the setup arising from the indirect oscillation excitation by a piezoelectric transducer. Photothermal excitation has been identified as a suitable method for exciting the cantilever in a direct manner. Here, we present a simple design for implementing photothermal excitation in a modified Multimode scan head from Bruker. Our approach is based on adding a few components only to keep the modifications as simple as possible and to maintain the low noise level of the original setup with a typical deflection noise density of about 15 fm/√(Hz) measured in aqueous solution. The success of the modification is illustrated by a comparison of the resonance spectra obtained with piezoelectric and photothermal excitation. The performance of the systems is demonstrated by presenting high-resolution images on bare calcite in liquid as well as organic adsorbates (Alizarin Red S) on calcite with simultaneous atomic resolution of the underlying calcite substrate.

  2. Acoustic Emission Testing of Power Plant Boiler%声发射技术在电站锅炉检测中的应用

    Institute of Scientific and Technical Information of China (English)

    林彤; 汪文有; 孔德连

    2013-01-01

    The acoustic emission technique was employed for the monitoring of couplet box tube socket weld injury changes in the boiler hydrostatic test process.By finding damage activity signals in the complex interference noise background and by the analysis of the mechanism of injury-induced acoustic emission characterization,the signals characteristic of weld cracks were obtained.The combination of real-time monitoring methods using acoustic emission and offline ultrasonic detection methods has resulted in a comprehensive evaluation of couplet box header internal damage location and damage development during hydrostatic testing process.The combination of the two methods,as well as the mutual authentication can improve the reliability,which plays an important role in guiding the on-site testing.%采用声发射技术在锅炉水压试验过程中对联箱管座焊缝损伤的变化进行动态监测,在复杂的干扰噪声中找到损伤活动信号,通过分析损伤产生声发射的机理,得到表征焊缝裂纹活动过程的信号特征.采用声发射实时监测方法与超声波离线检测方法的结合,对联箱管座内部损伤所在位置以及损伤在水压试验过程中动态发展的情况进行综合判断分析,两种方法的组合以及相互验证提高了结果判断的可靠性,对现场检测起到重要的指导作用.

  3. 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...

  4. In vitro measurement of ambient pressure changes using a realistic clinical setup

    DEFF Research Database (Denmark)

    Andersen, Klaus Scheldrup; Jensen, Jørgen Arendt

    2008-01-01

    cosine tapered pulse with a center frequency of 4 MHz and an acoustic pressure of 485 kPa was used for excitation. 64 elements were used in receive and the RF data was filtered and beamformed before further processing. To compensate for variations in bubble response and to make the estimates more robust...... have indicated that the amplitude of the subharmonic response from contrast agents is sensitive to the ambient pressure. This paper presents results from a new experimental setup for measuring the subharmonic response of a contrast agent when subjected to ambient over pressure. The setup is very...... flexible offering completely arbitrary excitation and data acquisition, fast and accurate ambient pressure control, and precise timing. More importantly, it resembles a realistic clinical setup using a single array transducer for transmit and receive. The standard signal processing steps usually seen...

  5. VSS BASED SESSION SETUP MECHANISM IN IMS

    Institute of Scientific and Technical Information of China (English)

    Cao Yufei; Liao Jianxin; Qi Qi; Zhu Xiaomin

    2009-01-01

    This paper proposes a novel session setup mechanism in IMS (IP Multimedia Subsystem) by introducing the functional entity termed VSS (Visitor Subscriber Server) which is used to provide registration and location management.The new mechanism aims at improving session setup procedure by a betterment of location management in IMS.Through the use of two-tier subscriber information database constituted by the HSS (Home Subscriber Server) and the VSS,the new mechanism seperates the registration procedure and location management from the S-CSCF (Serving-Call'Session Control Function),and makes them be handled by the VSS.At the same time,the new mechanism updates the signaling procedure of registration and session setup.With VSS based location management.the cost of registeration and session setup procedure as well as the delay of session setup procedure become lower.he cost and delay functious of the new session setup mechanism as well aus the cost function of new registeration are deduced.Then,simulations and analysis verify that the performance of this new mechanism gets the benefit in cost and time.

  6. Acoustic Ground-Impedance Meter

    Science.gov (United States)

    Zuckerwar, A. J.

    1983-01-01

    Helmoltz resonator used in compact, portable meter measures acoustic impedance of ground or other surfaces. Earth's surface is subject of increasing acoustical investigations because of its importance in aircraft noise prediction and measurment. Meter offers several advantages. Is compact and portable and set up at any test site, irrespective of landscape features, weather or other environmental condition.

  7. Cyclic Crack Growth Testing of an A.O. Smith Multilayer Pressure Vessel with Modal Acoustic Emission Monitoring and Data Assessment

    Science.gov (United States)

    Ziola, Steven M.

    2014-01-01

    Digital Wave Corp. (DWC) was retained by Jacobs ATOM at NASA Ames Research Center to perform cyclic pressure crack growth sensitivity testing on a multilayer pressure vessel instrumented with DWC's Modal Acoustic Emission (MAE) system, with captured wave analysis to be performed using DWCs WaveExplorerTM software, which has been used at Ames since 2001. The objectives were to document the ability to detect and characterize a known growing crack in such a vessel using only MAE, to establish the sensitivity of the equipment vs. crack size and / or relevance in a realistic field environment, and to obtain fracture toughness materials properties in follow up testing to enable accurate crack growth analysis. This report contains the results of the testing.

  8. Acoustic-structure coupled modal test based on PolyMAX%基于PolyMAX的声固耦合模态试验研究

    Institute of Scientific and Technical Information of China (English)

    高云凯; 冯海星; 马芳武; 杨亮

    2013-01-01

    Modal frequencies and modal shapes of a BIW ( body-in-white) reflect the inherent characteristics of an automotive body. They have an important influence on the interior noise. The car cavity also has modal frequencies and modal shapes. Acoustic modal test of a car cavity for a domestic SUV was performed with LMS data acquisition system. Firstly, the response points' signals were gained with a microphone array, and then the acoustic modal frequencies and modal shapes were extracted with PolyMAX method. The comparison between the acoustic modal frequencies and the test modal frequencies of the BIW showed that the first and the second acoustic modes of the car cavity are strongly coupled with the fourth and the tenth structural modes of the BIW. Finally, acoustic-structure coulpled resonance was verified through tests during the vehicle running. It was indicated that there are several ways to change the local modes of the automotive structure, such as, increasing the thickness- of the key components, adding damping layer in the roof and floor, and strengthening the roof with ribs and so on; these actions can destroy the strong coupling between the modes of the BIW and the acoustic modes of the car cavity, decrease the lower frequency boom in the automotive.%白车身的结构模态频率和模态振型反映了汽车车身结构的固有特性,对车内噪声有重要影响.车内空腔跟车身结构一样,同样拥有模态频率和模态振型.采用LMS数据采集系统对某国产SUV进行车内空腔声学模态试验.首先基于传声器阵列的方法获取响应点的信号,然后利用PolyMAX方法提取声学模态频率及振型.将声学模态频率与白车身结构模态频率进行对比分析,结果表明:车内空腔的第一、二阶声学模态分别跟白车身的第四、十阶结构模态有很强的耦合.最后通过实车测试验证了声固耦合共振时低频轰鸣的存在.可以在关键部件增加板厚、顶盖和地板附加阻

  9. Absorption boundary conditions for geomertical acoustics

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2012-01-01

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

  10. 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...

  11. 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...

  12. 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....

  13. 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.

  14. Embedded Acoustic Sensor Array for Engine Fan Noise Source Diagnostic Test: Feasibility of Noise Telemetry via Wireless Smart Sensors

    Science.gov (United States)

    Zaman, Afroz; Bauch, Matthew; Raible, Daniel

    2011-01-01

    Aircraft engines have evolved into a highly complex system to meet ever-increasing demands. The evolution of engine technologies has primarily been driven by fuel efficiency, reliability, as well as engine noise concerns. One of the sources of engine noise is pressure fluctuations that are induced on the stator vanes. These local pressure fluctuations, once produced, propagate and coalesce with the pressure waves originating elsewhere on the stator to form a spinning pressure pattern. Depending on the duct geometry, air flow, and frequency of fluctuations, these spinning pressure patterns are self-sustaining and result in noise which eventually radiate to the far-field from engine. To investigate the nature of vane pressure fluctuations and the resulting engine noise, unsteady pressure signatures from an array of embedded acoustic sensors are recorded as a part of vane noise source diagnostics. Output time signatures from these sensors are routed to a control and data processing station adding complexity to the system and cable loss to the measured signal. "Smart" wireless sensors have data processing capability at the sensor locations which further increases the potential of wireless sensors. Smart sensors can process measured data locally and transmit only the important information through wireless communication. The aim of this wireless noise telemetry task was to demonstrate a single acoustic sensor wireless link for unsteady pressure measurement, and thus, establish the feasibility of distributed smart sensors scheme for aircraft engine vane surface unsteady pressure data transmission and characterization.

  15. Synthesis of anisotropic swirling surface acoustic waves by inverse filter, towards integrated generators of acoustical vortices

    CERN Document Server

    Riaud, Antoine; Charron, Eric; Bussonnière, Adrien; Matar, Olivier Bou

    2015-01-01

    From radio-electronics signal analysis to biological samples actuation, surface acoustic waves (SAW) are involved in a multitude of modern devices. Despite this versatility, SAW transducers developed up to date only authorize the synthesis of the most simple standing or progressive waves such as plane and focused waves. In particular, acoustical integrated sources able to generate acoustical vortices (the analogue of optical vortices) are missing. In this work, we propose a flexible tool based on inverse filter technique and arrays of SAW transducers enabling the synthesis of prescribed complex wave patterns at the surface of anisotropic media. The potential of this setup is illustrated by the synthesis of a 2D analog of 3D acoustical vortices, namely "swirling surface acoustic waves". Similarly to their 3D counterpart, they appear as concentric structures of bright rings with a phase singularity in their center resulting in a central dark spot. Swirling SAW can be useful in fragile sensors whose neighborhood...

  16. Mechanisms of plastic instability and fracture of compressed and tensile tested Mg-Li alloys investigated using the acoustic emission method

    Directory of Open Access Journals (Sweden)

    A. Pawełek

    2016-01-01

    Full Text Available The results of the investigation of both mechanical and acoustic emission (AE behaviors of Mg4Li5Al alloy subjected to compression and tensile tests at room temperature are compared with the test results obtained using the same alloy and loading scheme but at elevated temperatures. The main aim of the paper is to investigate, to determine and to explain the possible influence of factors related with enhanced internal stresses such as: segregation of precipitates along grain boundaries or solute atoms along dislocations (Cottrell atmospheres or dislocation pile-ups at grain boundaries which create very high stress concentration leading to fracture. The results show that the plastic instabilities are related to the Portevin–Le Châtelier phenomenon (PL effect and they are correlated with the generation of AE peaks. The fractography of breaking samples was analyzed on the basis of light (optical, TEM and SEM images.

  17. Optymisation of equipment setup processes in enterprises

    Directory of Open Access Journals (Sweden)

    K. Grzybowska

    2012-10-01

    Full Text Available Fast equipment setup in a machine on production line is the key precondition to increase the fl exibility of the production. Methodology of SMED (Single Minute Exchange of Die is an example which allows reducing the time of setup practically to the minimum. The article presents the theoretical bases and required rules as well as case study conducted in one of chosen enterprises. This paper also answers the question if SMED methodology is applicable in metallurgical sector, presenting the example of shortening the time between the production of various metallurgical products manufactured in the machine for continuous casting of steel (COS in Polish.

  18. Braneworld setup and embedding in teleparallel gravity

    Directory of Open Access Journals (Sweden)

    A. Behboodi

    2015-01-01

    Full Text Available We construct the setup of a five-dimensional braneworld scenario in teleparallel gravity. Both cases of Minkowski and Friedmann–Robertson–Walker branes embedded in anti-de Sitter bulk are studied and the effective 4D action were studied. 4-dimensional local Lorentz invariance is found to be recovered in both cases. However, due to different junction conditions, the equations governing the 4D cosmological evolution differ from general relativistic case. Using the results of Ref. [13], we consider a simple inflationary scenario in this setup. The inflation parameters are found to be modified compared to general relativistic case.

  19. Building and commissioning of a setup to study ageing phenomena in gaseous detectors

    Energy Technology Data Exchange (ETDEWEB)

    Abuhoza, A., E-mail: aabuhoza@kacst.edu.sa [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt 64291 (Germany); King Abdulaziz City for Science and Technology (KACST), Riyadh (Saudi Arabia); Goethe-Universität, Frankfurt (Germany); Schmidt, H.R. [Eberhard-Karls-Universität, Tübingen (Germany); Biswas, S. [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Frankenfeld, U.; Hehner, J.; Schmidt, C.J. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt 64291 (Germany)

    2016-07-11

    In high-rate heavy-ion experiments, gaseous detectors encounter big challenges in terms of degradation of their performance due to a phenomenon called ageing. A setup for high precision ageing studies has been constructed and commissioned at the GSI detector laboratory. The setup as well as the gas system have been carefully optimized to reach a high sensitivity for ageing effects. Two different materials have been examined for their influence on gaseous detectors: RTV-3145 and Gerband 705. The details of the construction of the ageing test setup and the test results will be presented.

  20. Measurement Uncertainty Investigation in the Multi-probe OTA Setups

    DEFF Research Database (Denmark)

    Fan, Wei; Szini, Istvan Janos; Foegelle, M. D.

    2014-01-01

    Extensive efforts are underway to standardize over the air (OTA) testing of the multiple input multiple output (MIMO) capable terminals in COST IC1004, 3GPP RAN4 and CTIA. Due to the ability to reproduce realistic radio propagation environments inside the anechoic chamber and evaluate end user me...... chamber setup. This contribution presents the results of uncertainty measurements carried out in three practical multi-probe setups. Some sources of measurement errors, i.e. cable effect, cable termination, etc. are identified based on the measurement results.......Extensive efforts are underway to standardize over the air (OTA) testing of the multiple input multiple output (MIMO) capable terminals in COST IC1004, 3GPP RAN4 and CTIA. Due to the ability to reproduce realistic radio propagation environments inside the anechoic chamber and evaluate end user...... metrics in real world scenarios, the multi-probe based method has attracted huge interest from both industry and academia. This contribution attempts to identify some of the measurement uncertainties of the practical multi-probe setups and provide some guidance to establish the multi-probe anechoic...

  1. Acoustic detection of pneumothorax

    Science.gov (United States)

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

    2003-04-01

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

  2. Experimental Results for Direction of Arrival Estimation with a Single Acoustic Vector Sensor in Shallow Water

    Directory of Open Access Journals (Sweden)

    Alper Bereketli

    2015-01-01

    Full Text Available We study the performances of several computationally efficient and simple techniques for estimating direction of arrival (DOA of an underwater acoustic source using a single acoustic vector sensor (AVS in shallow water. Underwater AVS is a compact device, which consists of one hydrophone and three accelerometers in a packaged form, measuring scalar pressure and three-dimensional acceleration simultaneously at a single position. A very controlled experimental setup is prepared to test how well-known techniques, namely, arctan-based, intensity-based, time domain beamforming, and frequency domain beamforming methods, perform in estimating DOA of a source in different circumstances. Experimental results reveal that for almost all cases beamforming techniques perform best. Moreover, arctan-based method, which is the simplest of all, provides satisfactory results for practical purposes.

  3. Bitwise identical compiling setup: prospective for reproducibility and reliability of earth system modeling

    Directory of Open Access Journals (Sweden)

    R. Li

    2015-11-01

    Full Text Available Reproducibility and reliability are fundamental principles of scientific research. A compiling setup that includes a specific compiler version and compiler flags is essential technical supports for Earth system modeling. With the fast development of computer software and hardware, compiling setup has to be updated frequently, which challenges the reproducibility and reliability of Earth system modeling. The existing results of a simulation using an original compiling setup may be irreproducible by a newer compiling setup because trivial round-off errors introduced by the change of compiling setup can potentially trigger significant changes in simulation results. Regarding the reliability, a compiler with millions of lines of codes may have bugs that are easily overlooked due to the uncertainties or unknowns in Earth system modeling. To address these challenges, this study shows that different compiling setups can achieve exactly the same (bitwise identical results in Earth system modeling, and a set of bitwise identical compiling setups of a model can be used across different compiler versions and different compiler flags. As a result, the original results can be more easily reproduced; for example, the original results with an older compiler version can be reproduced exactly with a newer compiler version. Moreover, this study shows that new test cases can be generated based on the differences of bitwise identical compiling setups between different models, which can help detect software bugs or risks in the codes of models and compilers and finally improve the reliability of Earth system modeling.

  4. Full Scale Test of a SSP 34m boxgirder 2

    DEFF Research Database (Denmark)

    Jensen, Find Mølholt; Branner, Kim; Nielsen, Per Hørlyk;

    This report presents the setup and result from three static full-scale tests of the reinforced glass fiber/epoxy box girder used in a 34m wind turbine blade. One test was without reinforcement one with cap reinforcement and the final test was with rib reinforcement. The cap reinforcement test......, no conclusions are drawn. These can be found in papers and patent referenced in the data report. Various kinds of measuring equipment have been used during these tests: acoustic emission, force transducers, strain gauges and optical deformation measuring system (DIC). The experimental investigation consisted...

  5. Acoustic biosensors

    Science.gov (United States)

    Fogel, Ronen; Seshia, Ashwin A.

    2016-01-01

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

  6. Numerical study of a confocal ultrasonic setup for creation of cavitation

    Energy Technology Data Exchange (ETDEWEB)

    Lafond, Maxime, E-mail: maxime.lafond@inserm.fr; Chavrier, Françoise; Prieur, Fabrice [Inserm, U1032, LabTau, Lyon, F-69003 (France); Université de Lyon, Lyon, F-69003 (France); Université Lyon 1, Lyon, F-69003 (France); Mestas, Jean-Louis; Lafon, Cyril [Inserm, U1032, LabTau, Lyon, F-69003 (France); Université de Lyon, Lyon, F-69003 (France); Université Lyon 1, Lyon, F-69003 (France); Caviskills SAS, Vaulx-En-Velin, F-69120 (France)

    2015-10-28

    Acoustic cavitation is used for various therapeutic applications such as local enhancement of drug delivery, histotripsy or hyperthermia. One of the utmost important parameter for cavitation creation is the rarefaction pressure. The typical magnitude of the rarefaction pressure required to initiate cavitation from gas dissolved in tissue is beyond the range of the megapascal. Because nonlinear effects need to be taken into account, a numerical simulator based on the Westervelt equation was used to study the pressure waveform and the acoustic field generated by a setup for creation of cavitation consisting of two high intensity focused ultrasound transducers mounted confocally. At constant acoustic power, simulations with only one and both transducers from the confocal setup showed that the distortion of the pressure waveform due to the combined effects of nonlinearity and diffraction is less pronounced when both confocal transducers are used. Consequently, the confocal setup generates a greater peak negative pressure at focus which is more favorable for cavitation initiation. Comparison between the confocal setup and a single transducer with the same total emitting surface puts in evidence the role of the spatial separation of the two beams. Furthermore, it has been previously shown that the location of the peak negative pressure created by a single transducer shifts from focus towards the transducers in the presence of nonlinear effects. The simulator was used to study a configuration where the acoustical axes of transducers intersect on the peak negative pressure instead of the geometrical focus. For a representative confocal setup, namely moderate nonlinear effects, a 2% increase of the peak negative pressure and 8% decrease of the peak positive pressure resulted from this configuration. These differences tend to increase by increasing nonlinear effects. Although the optimal position of the transducers varies with the nonlinear regimen, the intersection point

  7. Droplets Acoustics

    CERN Document Server

    Dahan, Raphael; Carmon, Tal

    2015-01-01

    Contrary to their capillary resonances (Rayleigh, 1879) and their optical resonances (Ashkin, 1977), droplets acoustical resonances were rarely considered. Here we experimentally excite, for the first time, the acoustical resonances of a droplet that relies on sound instead of capillary waves. Droplets vibrations at 37 MHz rates and 100 quality factor are optically excited and interrogated at an optical threshold of 68 microWatt. Our vibrations span a spectral band that is 1000 times higher when compared with drops previously-studied capillary vibration.

  8. Identification of a Critical Time with Acoustic Emission Monitoring during Static Fatigue Tests on Ceramic Matrix Composites: Towards Lifetime Prediction

    Directory of Open Access Journals (Sweden)

    Nathalie Godin

    2016-02-01

    Full Text Available Non-oxide fiber-reinforced ceramic-matrix composites are promising candidates for some aeronautic applications that require good thermomechanical behavior over long periods of time. This study focuses on the behavior of a SiCf/[Si-B-C] composite with a self-healing matrix at intermediate temperature under air. Static fatigue experiments were performed below 600 °C and a lifetime diagram is presented. Damage is monitored both by strain measurement and acoustic emission during the static fatigue experiments. Two methods of real-time analysis of associated energy release have been developed. They allow for the identification of a characteristic time that was found to be close to 55% of the measured rupture time. This critical time reflects a critical local energy release assessed by the applicability of the Benioff law. This critical aspect is linked to a damage phase where slow crack growth in fibers is prevailing leading to ultimate fracture of the composite.

  9. PGNAA neutron source moderation setup optimization

    CERN Document Server

    Zhang, Jinzhao

    2013-01-01

    Monte Carlo simulations were carried out to design a prompt {\\gamma}-ray neutron activation analysis (PGNAA) thermal neutron output setup using MCNP5 computer code. In these simulations the moderator materials, reflective materials and structure of the PGNAA 252Cf neutrons of thermal neutron output setup were optimized. Results of the calcuations revealed that the thin layer paraffin and the thick layer of heavy water moderated effect is best for 252Cf neutrons spectrum. The new design compared with the conventional neutron source design, the thermal neutron flux and rate were increased by 3.02 times and 3.27 times. Results indicate that the use of this design should increase the neutron flux of prompt gamma-ray neutron activation analysis significantly.

  10. Test of the Feasibility and Accuracy of Mass and Velocity Measurements on Pellets in Flight in a Microwave Set-Up with a Pass-Hole in the Transmission Line

    DEFF Research Database (Denmark)

    Andersen, Verner; Andersen, P.

    The feasibility of mass and velocity measurements on pellets in flight without use of optical equipment has been tested. The mass is measured by a microwave system, and the velocity is measured by a time of flight in a double interaction with the microwave system. The influence of the size...

  11. Extensive Characterization of Cracking in As-fabricated Composite Ceramic Panels Via Ultrasonic and X-ray Computed Tomography Testing

    Science.gov (United States)

    2011-08-01

    ultrasonically scanned using a phased array pulse-echo immersion (water) setup. As the acoustic waves were transmitted into the specimens, material...and/or fabrication damage. Testing was conducted using a 64-element, 10-MHz linear phased array transducer. A total of 32 active elements were...reconstruction LDA linear detector array NDE nondestructive evaluation NDT nondestructive testing RO rotate-only SOD source-to-object-distance

  12. Effect of acoustic field parameters on arc acoustic binding during ultrasonic wave-assisted arc welding.

    Science.gov (United States)

    Xie, Weifeng; Fan, Chenglei; Yang, Chunli; Lin, Sanbao

    2016-03-01

    As a newly developed arc welding method, power ultrasound has been successfully introduced into arc and weld pool during ultrasonic wave-assisted arc welding process. The advanced process for molten metals can be realized by utilizing additional ultrasonic field. Under the action of the acoustic wave, the plasma arc as weld heat source is regulated and its characteristics make an obvious change. Compared with the conventional arc, the ultrasonic wave-assisted arc plasma is bound significantly and becomes brighter. To reveal the dependence of the acoustic binding force on acoustic field parameters, a two-dimensional acoustic field model for ultrasonic wave-assisted arc welding device is established. The influences of the radiator height, the central pore radius, the radiator radius, and curvature radius or depth of concave radiator surface are discussed using the boundary element method. Then the authors analyze the resonant mode by this relationship curve between acoustic radiation power and radiator height. Furthermore, the best acoustic binding ability is obtained by optimizing the geometric parameters of acoustic radiator. In addition, three concave radiator surfaces including spherical cap surface, paraboloid of revolution, and rotating single curved surface are investigated systematically. Finally, both the calculation and experiment suggest that, to obtain the best acoustic binding ability, the ultrasonic wave-assisted arc welding setup should be operated under the first resonant mode using a radiator with a spherical cap surface, a small central pore, a large section radius and an appropriate curvature radius.

  13. Acoustic/Magnetic Stress Sensor

    Science.gov (United States)

    Heyman, J. S.; Namkung, M.

    1986-01-01

    High-resolution sensor fast, portable, does not require permanent bonding to structure. Sensor measures nondestructively type (compressive or tensile) and magnitude of stresses and stress gradients present in class of materials. Includes precise high-resolution acoustic interferometer, sending acoustic transducer, receiving acoustic transducer, electromagnet coil and core, power supply, and magnetic-field-measuring device such as Hall probe. This measurement especially important for construction and applications where steel is widely used. Sensor useful especially for nondestructive evaluation of stress in steel members because of portability, rapid testing, and nonpermanent installation.

  14. Failure Behavior of Plasma-Sprayed Yttria-Stabilized Zirconia Thermal Barrier Coatings Under Three-Point Bending Test via Acoustic Emission Technique

    Science.gov (United States)

    Wang, L.; Ni, J. X.; Shao, F.; Yang, J. S.; Zhong, X. H.; Zhao, H. Y.; Liu, C. G.; Tao, S. Y.; Wang, Y.; Li, D. Y.

    2017-01-01

    In this paper, the failure behavior of plasma-sprayed yttria-stabilized zirconia thermal barrier coatings fabricated by atmospheric plasma spraying (APS-TBCs) under three-point bending (3PB) test has been characterized via acoustic emission (AE) technique. Linear positioning method has been adopted to monitor dynamic failure process of the APS-TBCs under 3PB test. The investigation results indicate that the variation of AE parameters (AE event counts, amplitudes and AE energy) corresponds well with the change of stress-strain curve of the loading processes. The failure mechanism was analyzed based on the characteristics of AE parameters. The distribution of frequency of crack propagation has been obtained. The AE signals came from two aspects: i.e., plastic deformation of substrates, initiation and propagation of the cracks in the coatings. The AE analysis combined with cross-sectional observation has indicated that many critical cracks initiate at the surface of the top-coat. And some main cracks tend to propagate toward the substrate/bond-coat interface. The actual failure mechanism of the APS-TBCs under 3PB test is attributed to the debonding of metallic coating from the substrates and the propagation of the horizontal crack along the substrate/bond-coat interface under the action of flexural moment.

  15. Comparison of Channel Emulation Techniques in Multiprobe Anechoic Chamber Setups

    DEFF Research Database (Denmark)

    Llorente, Ines Carton; Fan, Wei; Nielsen, Jesper Ødum;

    2015-01-01

    This paper compares two different techniques for channel emulation in multiprobe anechoic chamber based setups, which is a candidate solution for the standardization of MIMO OTA performance testing of mobile devices. The comparison is performed via simulations of the field distribution, temporal...... correlation, and spatial correlation emulated by these methods for different number of probes. Results show that the emulation accuracy of the field distribution and temporal correlation are degraded when the emulation technique uses a single sinusoid per probe antenna, while the emulation accuracy...

  16. A simple configuration setup for compton suppression spectroscopy

    CERN Document Server

    Hai, N X; Dien, N N; Tan, V H; Hoa, N D

    2013-01-01

    The fast timing, standard timing and easy timing are popular timing configurations of compton suppression spectroscopy. Such spectroscopes always use a module of coincidence or time-to-amplitude converter (TAC). A compton suppression spectroscopy with semi-timing configuration is presented in this paper. The semi-timing configuration is relatively simple and easy system setup, especially this spectroscopy does not need to use module of coincidence or TAC. The performance of spectroscopy was tested and summarized. The count rate background, full peak efficiency and the ratios of area/background of peaks in suppressed and unsuppressed modes were comparative.

  17. A magnetic resonance-compatible experimental set-up for hyperthermia studies.

    Science.gov (United States)

    Jayasundar, R; Hall, L D; Bleehen, N M

    1999-11-01

    This study presents the development and testing of an experimental set-up for simultaneous measurements of pH (intracellular by MR and extracellular by fibre-optic pH meter), tumour bio-energetics (by MR), and core/tumour temperatures (by thermocouples) in tumour-bearing mice. Potential sources of measurement errors when using these techniques concurrently in an MR set-up are discussed. Emphasis is placed on simple practical solutions to these problems.

  18. 航天器组件声振组合环境试验与仿真技术%Vibro-acoustic environment test and its simulation for spacecraft components

    Institute of Scientific and Technical Information of China (English)

    杨江; 张俊刚; 方贵前; 晏廷飞

    2014-01-01

    A vibro-acoustic environment test for the solar panel of a spacecraft is conducted. Two typical vibro-acoustic analysis methods, the hybrid FE-SEA and the coupled FE/BEM, are adopted to model and analyze the solar panel structure under a random vibration and/or acoustic excitation condition with the VA One. The comparison between the simulation and the vibro-acoustic environment test shows that the components can be tested effectively by the vibro-acoustic environment test, and the simulation models are validated by the consistency of the predicted response with the test data. The hybrid FE-SEA method is better in the lower frequency and the coupled FE/BEM is better in the medium and higher frequency.%研究了某航天器太阳电池板的声振组合环境试验技术,并使用FE-SEA混合方法和耦合FE/BEM方法建立了太阳电池板的仿真模型,进行了声振组合激励下的响应仿真预示。仿真结果和试验结果的对比分析结果表明:声振组合试验对航天器组件的考核更充分;耦合 FE/BEM 方法更适合进行低频响应分析,而 FE-SEA混合方法在中高频段更具优势,且两种方法的仿真预示响应和试验结果基本一致。

  19. Magnetic resonance imaging of acoustic streaming: absorption coefficient and acoustic field shape estimation.

    Science.gov (United States)

    Madelin, Guillaume; Grucker, Daniel; Franconi, Jean-Michel; Thiaudiere, Eric

    2006-07-01

    In this study, magnetic resonance imaging (MRI) is used to visualize acoustic streaming in liquids. A single-shot spin echo sequence (HASTE) with a saturation band perpendicular to the acoustic beam permits the acquisition of an instantaneous image of the flow due to the application of ultrasound. An average acoustic streaming velocity can be estimated from the MR images, from which the ultrasonic absorption coefficient and the bulk viscosity of different glycerol-water mixtures can be deduced. In the same way, this MRI method could be used to assess the acoustic field and time-average power of ultrasonic transducers in water (or other liquids with known physical properties), after calibration of a geometrical parameter that is dependent on the experimental setup.

  20. Self-sustained aero-acoustic pulsations in gas transport systems: Experimental study of the influence of closed side branches

    Science.gov (United States)

    Bruggeman, J. C.; Hirschberg, A.; van Dongen, M. E. H.; Wijnands, A. P. J.; Gorter, J.

    1991-11-01

    A theoretical model is proposed for the aero-acoustic sources responsible for low-frequency self-sustained pulsations in pipes with closed side branches. The theory successfully explains the acoustic and hydrodynamic conditions for resonance in experiments with a single side branch. It also predicts the order of magnitude of the pulsation amplitude and the effect of losses due to friction and radiation. A high pulsation level, with acoustic velocities of the order of magnitude of the main flow, is observed in a double side branch set-up when the edges at the junctions are rounded. When in the double side branch set-up the rounded upstream edge of the second T-joint is replaced by a sharp edge, the pulsation amplitude is reduced by a factor of five. This effect, which can be explained with the theory of vortex sound, leads us to the design of spoilers. Various "spoilers" have been tested in scale model and full scale experiments. Some of these reduce the pulsation level by 40 dB.

  1. Portable acoustic myography

    DEFF Research Database (Denmark)

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

    2013-01-01

    to register at sufficient sampling speed. With modern amplifiers and digital sound recording this has changed, and such assessment during movement outside a laboratory setting may be possible. Our aim was to develop a setup for muscle-sound assessment, which could be reliably applied in any local setting...... with the possibility of being applied in most clinical, sports, and home settings. Muscle sound gives a representation of the work of each muscle group during a complex movement, illustrated here by a step test, which revealed both concentric and eccentric activity. The method in the presented new setup has great...... potential for assessment of function in patients with musculoskeletal complaints in out-of-clinic settings, as well as in sports....

  2. Global optimisation methods for poroelastic material characterisation using a clamped sample in a Kundt tube setup

    Science.gov (United States)

    Vanhuyse, Johan; Deckers, Elke; Jonckheere, Stijn; Pluymers, Bert; Desmet, Wim

    2016-02-01

    The Biot theory is commonly used for the simulation of the vibro-acoustic behaviour of poroelastic materials. However, it relies on a number of material parameters. These can be hard to characterize and require dedicated measurement setups, yielding a time-consuming and costly characterisation. This paper presents a characterisation method which is able to identify all material parameters using only an impedance tube. The method relies on the assumption that the sample is clamped within the tube, that the shear wave is excited and that the acoustic field is no longer one-dimensional. This paper numerically shows the potential of the developed method. It therefore performs a sensitivity analysis of the quantification parameters, i.e. reflection coefficients and relative pressures, and a parameter estimation using global optimisation methods. A 3-step procedure is developed and validated. It is shown that even in the presence of numerically simulated noise this procedure leads to a robust parameter estimation.

  3. Potential Damage to Flight Hardware from MIL-STD-462 CS02 Setup

    Science.gov (United States)

    Harris, Patrick K.; Block, Nathan F.

    2003-01-01

    The MIL-STD-462 CS02 conducted susceptibility test setup includes an audio transformer, with the secondary used as an inductor, and a large capacitor. Together, these two components form an L-type low-pass filter to minimize the injected test signal input into the power source. Some flight hardware power input configurations are not compatible with this setup and break into oscillation when powered up. This, in turn, can damage flight hardware. Such an oscillation resulted in the catastrophic failure of an item tested in the Goddard Space Flight Center (GSFC) Large electromagnetic compatibility (EMC) Test Facility.

  4. On-line surveillance of lubricants in bearings by means of surface acoustic waves.

    Science.gov (United States)

    Lindner, Gerhard; Schmitt, Martin; Schubert, Josephine; Krempel, Sandro; Faustmann, Hendrik

    2010-01-01

    The acoustic wave propagation in bearings filled with lubricants and driven by pulsed excitation of surface acoustic waves has been investigated with respect to the presence and the distribution of different lubricants. Experimental setups, which are based on the mode conversion between surface acoustic waves and compression waves at the interface between a solid substrate of the bearing and a lubricant are described. The results of preliminary measurements at linear friction bearings, rotation ball bearings and axial cylinder roller bearings are presented.

  5. Evaluation of microscopic deformation behaviors of metal matrix composite by means of SFC test and acoustic emission (Part I :Effect of heat treatment on IFSS)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon Hyun; Kang, Moon Phil [Pusan National University, Pusan (Korea, Republic of)

    1998-11-15

    Metal matrix composites(MMCs) are rapidly becoming one of the strongest candidates for structural materials for high temperature application. It is well recognized that MMCs always experience at least one large cool-down from processing temperature before any significant applied service loading. Due to the large difference in thermal expansion coefficient between the fiber and matrix, large thermal residual stresses generally develop in composites. It was reported from many previous studies that the effects of thermal residual stress on mechanical properties and fracture behavior were much more complex and dramatic than conventional engineering materials. Therefore it is crucial to evaluate the effect of heat treatment which changes the characteristic of distribution of thermal residual stress in MMCs. Single fiber composite(SFC) test based on the balance in a micromechanical model is a quite convenient method to evaluate interfacial shear strength(IFSS) and the failure mode of composite. In this study the effect of heat treatment on IFSS and the microscopic failure mechanism of MMC is investigated by combining acoustic emission(AE) technique with fragmentation test. The characteristic of AE signal, IFSS and microscopic failure mechanism due to heat treatment condition is discussed.

  6. Evaluation of Microscopic Deformation Behaviors of Metal Matrix Composite due to Heat Treatment by means of SFC Test and Acoustic Emission

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Moon Phil; Lee, Joon Hyun [Pusan National University, Busan (Korea, Republic of)

    2000-10-15

    Metal matrix composite(MMCs) have been rapidly becoming one of the strongest candidates for structural materials for high temperature application. It is well recognized that MMCs always experience at least one large cool-down from processing temperature before my significant applied service loading. Due to the large difference in thermal expansion coefficient between the fiber and matrix, large thermal residual stresses generally develop in composites. It was reported from many previous studies that the effects of thermal residual stress on mechanical properties and fracture behavior were much more complex and dramatic than conventional engineering materials. Therefore it is crucial to evaluate the effect of heat treatment which changes the characteristic of distribution of thermal residual stress in MMCs. Single fiber composite(SFC) test based on the balance in a micromechanical model is a quite convenient method to evaluate interfacial shear strength(IFSS) and the failure mode of composite. In this study the effect of heat treatment on IFSS and the microscopic failure mechanism of MMC is investigated by combining acoustic emission(AE) technique with SFC test. The characteristic of AE signal, IFSS and microscopic failure mechanism due to heat treatment condition is discussed

  7. Composite Inflation Setup and Glueball Inflation

    DEFF Research Database (Denmark)

    Bezrukov, Fedor; Channuie, Phongpichit; Jark Joergensen, Jakob;

    2012-01-01

    We explore the paradigm according to which inflation is driven by a four-dimensional strongly coupled dynamics coupled non-minimally to gravity. We start by introducing the general setup, both in the metric and Palatini formulation, for generic models of composite inflation. We then analyze......-minimally to gravity. We demonstrate that it is possible to achieve successful inflation with the confining scale of the underlying Yang-Mills theory naturally of the order of the grand unified energy scale. We also argue that within the metric formulation models of composite inflation lead to a more consistent...

  8. Recent IBA setup improvements in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, P.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile)]. E-mail: pmiranda@fisica.ciencias.uchile.cl; Chesta, M.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Cancino, S.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Morales, J.R. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Dinator, M.I. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Wachter, J.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Tenreiro, C. [Facultad de Ingenieria, Campus Curico, Universidad de Talca (Chile)

    2006-07-15

    This paper describes the main characteristics of the ion beam facility based on a 3.75 MeV Van de Graaff accelerator model KN3750 of HVE at University of Chile. Recent setup improvements on three beam lines available, one dedicated for PIXE analyzes, one designed for RBS-PESA analyzes and a multipurpose vacuum chamber, as well as beam energy calibration experiments of the accelerator will be summarized. Current research activities are focused on the application of the different IBA techniques for the material, biological and environmental analysis. In addition, nuclear activation analysis and the study of nuclear reactions of astrophysical interest has begun to be developed as basic research.

  9. LDA optical setup using holographic imaging configuration

    Science.gov (United States)

    Ghosh, Abhijit; Nirala, A. K.

    2015-11-01

    This paper describes one of the possible ways for improving fringe quality at LDA measuring volume using a holographic imaging configuration consisting of a single hololens. For its comparative study with a conventional imaging configuration, a complete characterization of fringes formed at the measurement volume by both the configuration is presented. Results indicate the qualitative as well as quantitative improvement of the fringes formed at measurement volume by the holographic imaging configuration. Hence it is concluded that use of holographic imaging configuration for making LDA optical setup is a better choice than the conventional one.

  10. Acoustic dose and acoustic dose-rate.

    Science.gov (United States)

    Duck, Francis

    2009-10-01

    Acoustic dose is defined as the energy deposited by absorption of an acoustic wave per unit mass of the medium supporting the wave. Expressions for acoustic dose and acoustic dose-rate are given for plane-wave conditions, including temporal and frequency dependencies of energy deposition. The relationship between the acoustic dose-rate and the resulting temperature increase is explored, as is the relationship between acoustic dose-rate and radiation force. Energy transfer from the wave to the medium by means of acoustic cavitation is considered, and an approach is proposed in principle that could allow cavitation to be included within the proposed definitions of acoustic dose and acoustic dose-rate.

  11. Acoustic solitons: A robust tool to investigate the generation and detection of ultrafast acoustic waves

    Science.gov (United States)

    Péronne, Emmanuel; Chuecos, Nicolas; Thevenard, Laura; Perrin, Bernard

    2017-02-01

    Solitons are self-preserving traveling waves of great interest in nonlinear physics but hard to observe experimentally. In this report an experimental setup is designed to observe and characterize acoustic solitons in a GaAs(001) substrate. It is based on careful temperature control of the sample and an interferometric detection scheme. Ultrashort acoustic solitons, such as the one predicted by the Korteweg-de Vries equation, are observed and fully characterized. Their particlelike nature is clearly evidenced and their unique properties are thoroughly checked. The spatial averaging of the soliton wave front is shown to account for the differences between the theoretical and experimental soliton profile. It appears that ultrafast acoustic experiments provide a precise measurement of the soliton velocity. It allows for absolute calibration of the setup as well as the response function analysis of the detection layer. Moreover, the temporal distribution of the solitons is also analyzed with the help of the inverse scattering method. It shows how the initial acoustic pulse profile which gives birth to solitons after nonlinear propagation can be retrieved. Such investigations provide a new tool to probe transient properties of highly excited matter through the study of the emitted acoustic pulse after laser excitation.

  12. Set-up and performance testing of a superconducting magnet cooled by a G-M cryocooler%G-M制冷机冷却的超导磁体研制及性能试验

    Institute of Scientific and Technical Information of China (English)

    杨志达; 刘华军; 孙浩伟; 武玉; 韩伟实

    2009-01-01

    针对超导磁体液氦易挥发、需要不断补充的问题,为研制的超导磁体加装了G-M制冷机.为了使磁体漏热量与制冷机的两级制冷量相匹配,对系统液氦和液氮温区的传导漏热、辐射漏热和对流漏热3种热载荷进行了计算,对制冷机单独进行了制冷量和最低温度的测试,结果表明磁体漏热量与制冷机制冷量相匹配.制冷机与磁体杜瓦装配后用制冷机冷却磁体,5 d时间将磁体温度冷却到4.2K.向磁体输入液氦并励磁,3 d时间内超导液面计数值下降不明显,表明磁体可实现自供液氦和零蒸发,装置在无补液情况下可长期运行.%A Gifford-McMahon (G-M) cryocooler was installed in a superconducting magnet which, due to evaporation of liquid helium, needed continuous helium replenishment. The thermal loss which was causing evaporation needed to be matched by the cooling capacity of the 1st and 2nd heads of its proposed refrigeration cryocooler. The thermal loss from conduction, radiation and convection in systemic liquid helium and the liquid helium warm area was calculated. The cooling capacity and the lowest temperature achievable by the cryocooler were also tested. Since the cryocooler was intended to cool off the magnet's cryostat, they were physically integrated. The cryostat achieved a temperature of 4.2K in five days. Field excitation and superconducting liquid level dropped insignificantly in those three days. This indicates that liquid helium can be supplied to the magnet with zero vaporization loss, allowing the magnet to run a long time without renewing liquid helium.

  13. Propagation behavior of acoustic wave in wood

    Institute of Scientific and Technical Information of China (English)

    Huadong Xu; Guoqi Xu; Lihai Wang; Lei Yu

    2014-01-01

    We used acoustic tests on a quarter-sawn poplar timbers to study the effects of wood anisotropy and cavity defects on acoustic wave velocity and travel path, and we investigated acoustic wave propagation behavior in wood. The timber specimens were first tested in unmodified condition and then tested after introduction of cavity defects of varying sizes to quantify the transmitting time of acoustic waves in laboratory conditions. Two-dimensional acoustic wave contour maps on the radial section of specimens were then simulated and analyzed based on the experimental data. We tested the relationship between wood grain and acoustic wave velocity as waves passed in various directions through wood. Wood anisotropy has significant effects on both velocity and travel path of acoustic waves, and the velocity of waves passing longitudinally through timbers exceeded the radial velocity. Moreover, cavity defects altered acoustic wave time contours on radial sections of timbers. Acous-tic wave transits from an excitation point to the region behind a cavity in defective wood more slowly than in intact wood.

  14. Acoustic emission analysis in overall fatigue testing of a wind rotor blade; Schallemissionsanalyse beim Gesamtermuedungstest eines Windkraftrotorblattes

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, Eberhard; Frankenstein, Bernd; Schubert, Lars [Fraunhofer-Instiut fuer Zerstoerungsfreie Pruefverfahren (IZFP), Dresden (Germany)

    2009-07-01

    The Fraunhofer Institut fuer zerstoerungsfreie Pruefverfahren Dresden (IZFP-D, Fraunhofer Institute of Nondestructive Testing) is developing condition monitoring systems (CMS) for safety-relevant components. By permanent monitoring, e.g. of wind rotors, aircraft components or pipelines, these systems will ensure high avalability during the whole component life. Crack initiation, crack propagation or delamination can be detected and repaired at an early stage. Early repair will prolong the component life, and outage periods can be reduced. Currently, full-scale fatigue tests are made on a 40 m wind rotor blade of CFRP and GFRP materials. After a static pre-load period, 2,000,000 fatigue cycles will be applied. The contribution describes the measuring technology and the evaluation methods, in particular event identification and parametrization. Finally, the current experimental status is outlined, fatigue test results so far are presented, and development trends are indicated. (orig.)

  15. Cryogenic setup for trapped ion quantum computing

    Science.gov (United States)

    Brandl, M. F.; van Mourik, M. W.; Postler, L.; Nolf, A.; Lakhmanskiy, K.; Paiva, R. R.; Möller, S.; Daniilidis, N.; Häffner, H.; Kaushal, V.; Ruster, T.; Warschburger, C.; Kaufmann, H.; Poschinger, U. G.; Schmidt-Kaler, F.; Schindler, P.; Monz, T.; Blatt, R.

    2016-11-01

    We report on the design of a cryogenic setup for trapped ion quantum computing containing a segmented surface electrode trap. The heat shield of our cryostat is designed to attenuate alternating magnetic field noise, resulting in 120 dB reduction of 50 Hz noise along the magnetic field axis. We combine this efficient magnetic shielding with high optical access required for single ion addressing as well as for efficient state detection by placing two lenses each with numerical aperture 0.23 inside the inner heat shield. The cryostat design incorporates vibration isolation to avoid decoherence of optical qubits due to the motion of the cryostat. We measure vibrations of the cryostat of less than ±20 nm over 2 s. In addition to the cryogenic apparatus, we describe the setup required for an operation with 40Ca+ and 88Sr+ ions. The instability of the laser manipulating the optical qubits in 40Ca+ is characterized by yielding a minimum of its Allan deviation of 2.4 ṡ 10-15 at 0.33 s. To evaluate the performance of the apparatus, we trapped 40Ca+ ions, obtaining a heating rate of 2.14(16) phonons/s and a Gaussian decay of the Ramsey contrast with a 1/e-time of 18.2(8) ms.

  16. Cryogenic setup for trapped ion quantum computing

    CERN Document Server

    Brandl, M F; Postler, L; Nolf, A; Lakhmanskiy, K; Paiva, R R; Möller, S; Daniilidis, N; Häffner, H; Kaushal, V; Ruster, T; Warschburger, C; Kaufmann, H; Poschinger, U G; Schmidt-Kaler, F; Schindler, P; Monz, T; Blatt, R

    2016-01-01

    We report on the design of a cryogenic setup for trapped ion quantum computing containing a segmented surface electrode trap. The heat shield of our cryostat is designed to attenuate alternating magnetic field noise, resulting in 120~dB reduction of 50~Hz noise along the magnetic field axis. We combine this efficient magnetic shielding with high optical access required for single ion addressing as well as for efficient state detection by placing two lenses each with numerical aperture 0.23 inside the inner heat shield. The cryostat design incorporates vibration isolation to avoid decoherence of optical qubits due to the motion of the cryostat. We measure vibrations of the cryostat of less than $\\pm$20~nm over 2~s. In addition to the cryogenic apparatus, we describe the setup required for an operation with $^{\\mathrm{40}}$Ca$^{\\mathrm{+}}$ and $^{\\mathrm{88}}$Sr$^{\\mathrm{+}}$ ions. The instability of the laser manipulating the optical qubits in $^{\\mathrm{40}}$Ca$^{\\mathrm{+}}$ is characterized yielding a min...

  17. Full Scale Test of a SSP 34m box girder 1. Data report

    DEFF Research Database (Denmark)

    Jensen, Find Mølholt; Branner, Kim; Nielsen, Per Hørlyk;

    This report presents the setup and result of a full-scale test of a reinforced glass fibre/epoxy box girder used in 34m wind turbine blade. The tests were performed at the Blaest test facility in August 2006. The test is an important part of a research project established in cooperation between...... the box girder was loaded until failure. A comprehensive description of the test setup is given. This report deals only with tests and results. There are no conclusions on the data in this report, but references are given to publications, where the data are used and compared with FEM etc. Various kinds...... of measuring equipment have been used during these tests: acoustic emission, 330 strain gauges, 24 mechanical displacement devices and two optical deformation measuring systems. The mechanical displacement devices measured both global (absolute) and local (relative) deflection and the optical systems measured...

  18. Diagnostics of glass fiber reinforced polymers and comparative analysis of their fabrication techniques with the use of acoustic emission

    Science.gov (United States)

    Bashkov, O. V.; Bryansky, A. A.; Panin, S. V.; Zaikov, V. I.

    2016-11-01

    Strength properties of the glass fiber reinforced polymers (GFRP) fabricated by vacuum and vacuum autoclave molding techniques were analyzed. Measurements of porosity of the GFRP parts manufactured by various molding techniques were conducted with the help of optical microscopy. On the basis of experimental data obtained by means of acoustic emission hardware/software setup, the technique for running diagnostics and forecasting the bearing capacity of polymeric composite materials based on the result of three-point bending tests has been developed. The operation principle of the technique is underlined by the evaluation of the power function index change which takes place on the dependence of the total acoustic emission counts versus the loading stress.

  19. ADAPTIVE ELLIPSOIDAL ACOUSTIC INFINITE ELEMENT

    Institute of Scientific and Technical Information of China (English)

    Yang Ruiliang; Wang Hongzhen

    2004-01-01

    It is shown that the basis of the ellipsoidal acoustic infinite element Burnett method,the multipole expansion,cannot represent real ellipsoidal acoustic field exactly.To solve the problem,a weight of angular direction is added to the multipole expansion.The comparison of the modified method and the prime method shows that the modified method can describe and solve the ellipsoidal acoustic field more accurately than ever.A dilating sphere is used to test the new method further.Unlike other infinite element methods,varied ratio of the ellipsoidal artificial boundary instead of sphere is used.The pressure value of the artificial boundary is utilized as the initial value of the new method.Then the radiating phenomena of the ellipsoidal acoustic field can be researched using the new method.These examples show the feasibility of the adaptive method.

  20. Detecting the Nonlinearity of Fish Acoustic Signals

    Institute of Scientific and Technical Information of China (English)

    REN Xinmin; YIN Li

    2006-01-01

    This paper discusses the nonlinearity of fish acoustic signals by using the surrogate data method.We compare the difference of three test statistics - time-irreversibility Trey, correlation dimension D2 and auto mutual information function Ⅰbetween the original data and the surrogate data.We come to the conclusion that there exists nonlinearity in the fish acoustic signals and there exist deterministic nonlinear components; therefore nonlinear dynamic theory can be used to analyze fish acoustic signals.

  1. Acoustic testing of a 1.5 pressure ratio low tip speed fan with a serrated rotor (QEP fan B scale model). [reduction of engine noise

    Science.gov (United States)

    Kazin, S. B.; Paas, J. E.; Minzner, W. R.

    1973-01-01

    A scale model of the bypass flow region of a 1.5 pressure ratio, single stage, low tip speed fan was tested with a serrated rotor leading edge to determine its effects on noise generation. The serrated rotor was produced by cutting teeth into the leading edge of the nominal rotor blades. The effects of speed and exhaust nozzle area on the scale models noise characteristics were investigated with both the nominal rotor and serrated rotor. Acoustic results indicate the serrations reduced front quadrant PNL's at takeoff power. In particular, the 200 foot (61.0 m) sideline noise was reduced from 3 to 4 PNdb at 40 deg for nominal and large nozzle operation. However, the rear quadrant maximum sideline PNL's were increased 1.5 to 3 PNdb at approach thust and up to 2 PNdb at takeoff thust with these serrated rotor blades. The configuration with the serrated rotor produced the lowest maximum 200 foot (61.0 m) sideline PNL for any given thust when the large nozzle (116% of design area) was employed.

  2. SU-E-J-22: A Feasibility Study On KV-Based Whole Breast Radiation Patient Setup

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Q [Rutgers Cancer Institute of New Jersey, New Brunswick, NJ (United States); Zhang, M; Yue, N; Chen, T [Rutgers University, New Brunswick, NJ (United States)

    2015-06-15

    Purpose: In room kilovoltage x-ray (kV) imaging provides higher contrast than Megavoltage (MV) imaging with faster acquisition time compared with on-board cone-beam computed tomography (CBCT), thus improving patient setup accuracy and efficiency. In this study we evaluated the clinical feasibility of utilizing kV imaging for whole breast radiation patient setup. Methods: For six breast cancer patients with whole breast treatment plans using two opposed tangential fields, MV-based patient setup was conducted by aligning patient markers with in room lasers and MV portal images. Beam-eye viewed kV images were acquired using Varian OBI system after the set up process. In house software was developed to transfer MLC blocks information overlaying onto kV images to demonstrate the field shape for verification. KV-based patient digital shift was derived by performing rigid registration between kV image and the digitally reconstructed radiography (DRR) to align the bony structure. This digital shift between kV-based and MV-based setup was defined as setup deviation. Results: Six sets of kV images were acquired for breast patients. The mean setup deviation was 2.3mm, 2.2mm and 1.8mm for anterior-posterior, superior-inferior and left-right direction respectively. The average setup deviation magnitude was 4.3±1.7mm for six patients. Patient with large breast had a larger setup deviation (4.4–6.2mm). There was no strong correlation between MV-based shift and setup deviation. Conclusion: A preliminary clinical workflow for kV-based whole breast radiation setup was established and tested. We observed setup deviation of the magnitude below than 5mm. With the benefit of providing higher contrast and MLC block overlaid on the images for treatment field verification, it is feasible to use kV imaging for breast patient setup.

  3. The ALMA Front-end Archive Setup and Performance

    Science.gov (United States)

    Wicenec, A.; Chen, A.; Checcucci, A.; Jeram, B.; Meuss, H.; Persson, A.; Burgos, P.; Cirami, R.

    2010-12-01

    The ALMA front-end archive system has to capture up to 64 MB/s for a period of several days plus the data of about 100,000 monitor points from all 66 antennas and the correlators. The main science data is delivered through corba based audio/video streams and finally stored on SATA disk arrays hosted on 6 computers and controlled by 12 daemons. All data is collected by software components running on computers in the antennas and then sent through dedicated fiber links to the Array Operations Site at 5000 m and from there to the Operations Support Facility (OSF) at 3000 m elevation. The various hardware and software components have been tuned and tested to be able to meet the performance requirements. This paper describes the setup and the various components in more detail and gives results of various test runs.

  4. ACOUSTIC EMISSION ANALYZER

    Directory of Open Access Journals (Sweden)

    J. J. Almeida-Pérez

    2004-12-01

    Full Text Available In this paper appears a solution for acoustic emission analysis commonly known as noise. For the accomplishmentof this work a personal computer is used, besides sensors (microphones and boards designed and built for signalconditioning. These components are part of a virtual instrument used for monitoring the acoustical emission. Themain goal of this work is to develop a virtual instrument that supplies many important data as the result of ananalysis allowing to have information in an easy and friendly way. Moreover this information is very useful forstudying and resolving several situations in planning, production and testing areas.The main characteristics of the virtual instrument are: signal analysis in time, effective power measurement inDecibels (dB, average intensity taken from the principle of paired microphones, as well as the data analysis infrequency. These characteristics are included to handle two information channels.

  5. Evaluation of the acoustic and non-acoustic properties of sound absorbing materials using a three-microphone impedance tube

    CERN Document Server

    Doutres, Olivier; Atalla, Noureddine; Panneton, Raymond; 10.1016/j.apacoust.2010.01.007

    2010-01-01

    This paper presents a straightforward application of an indirect method based on a three-microphone impedance tube setup to determine the non-acoustic properties of a sound absorbing porous material. First, a three-microphone impedance tube technique is used to measure some acoustic properties of the material (i.e., sound absorption coefficient, sound transmission loss, effective density and effective bulk modulus) regarded here as an equivalent fluid. Second, an indirect characterization allows one to extract its non-acoustic properties (i.e., static airflow resistivity, tortuosity, viscous and thermal characteristic lengths) from the measured effective properties and the material open porosity. The procedure is applied to four different sound absorbing materials and results of the characterization are compared with existing direct and inverse methods. Predictions of the acoustic behavior using an equivalent fluid model and the found non-acoustic properties are in good agreement with impedance tube measureme...

  6. ALBERTA - HEC test beam set-up in June 1999

    CERN Multimedia

    Vinter, M.

    1999-01-01

    Photo1 - HEC 2 (rear) being set up in the "clean" room. Photo2 - HEC 2 (rear) being craned onto rotating C. Photo3 - HEC 2 (rear) being rotated. Photo4 - A now well rotated HEC 2 (rear) is being craned off the C. Photo5 - HEC 2 (rear) installed in the cryostat. Photo6 - Part of the basic frame (the frame that sits in the very bottom of the cryostat). Photo7 - Part of the basic frame (one of the two frames which the 3 calorimeter modules sit on). Photo8 - The marriage frame.

  7. Setup of IN VIVO Breast Cancer Models for Nanodrug Testing

    DEFF Research Database (Denmark)

    Schifter, Søren

    2013-01-01

    Synthetic lethality is a promising concept for future cancer treatment and using siRNAs as the synthetic lethal drug component allows for also covering the space considered as non-druggable by conventional small molecule drugs. Systemic administration of naked siRNA, however, does not result...... for detection of the primary tumor and metastasis and the efficacy of siRNA delivery is measured by reporter gene-targeting siRNAs and in vivo imaging. The use of a uniform siRNA not affecting cellular processes would allow for standardized assessment of siRNA delivery to cancer cells without interferences via...... differential knockdown efficacies and the readout can directly be performed by quantitative imaging using a Caliper IVIS system. In one line of experiments, we engineered non-metastatic MCF-7 breast cancer cells to express the luminescent reporter firefly luciferase (Luc2) along with a pro-metastatic micro...

  8. A VDU experimental setup for fixation disparity evaluation

    Science.gov (United States)

    Sousa, Raul A. R. C.; Baptista, António M. G.

    2011-05-01

    A new experimental setup for any standard Video Display Unit (VDUET) with dichromatic glasses was developed for fixation disparity (FD) accessing. A computer software produce a dark field with white targets for central and peripheral fusion and two lines colors red and green for dissociated vision with the use of red and green filters. These lines can be moved right or left by the subject, until are seen apparently aligned. The real displacement between the lines is then recorded. The fixation curve (FC) is obtained by the interposition of prisms before one or both eyes, as in a regular commercial FD test. A comparison for FD and measurement time between this experimental setup and two commercially available methods, Wesson and Saladin cards, was performed in thirty-two university students. The means slope, x-intercept and y-intercept were 0.13, -0.22 and -5.63 for Saladin; 0.01, -2.29 and -1.88 for Wesson; and 0.61, -1.33 and -2.46 for VDUET. The mean measurement test time was 582.3 s, 501.3 s and 444.8 s for Saladin, Wesson and VDUET. The FC measured by these three methods was different but not statically significant (ANOVA one-way, Tukey post-hoc test) with the exception of the slope between Wesson test and VDUET (pSaladin and VDUET (p<0.01). The VDUET has some features that represent some improvement over the current commercial methods for DF measurement.

  9. Accuracy in tangential breast treatment set-up; A portal imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Tienhoven, G. van; Lanson, J.H.; Crabeels, D.; Heukelom, S.; Mijnheer, B.J. (Nederlands Kanker Inst. ' Antoni van Leeuwenhoekhuis' , Amsterdam (Netherlands))

    1991-12-01

    To test accuracy and reproducibility of tangential breast treatment set-up used in The Netherlands Cancer Institute, a portal imaging study was performed in 12 patients treated for early stage breast cancer. With an on-line electronic portal imaging device (EPID) images were obtained of each patient in several fractions and compared with simulator films and with each other. In 5 patients multiple images (on the average 7) per fraction were obtained to evaluate set-up variations due to respiratory movement. The central lung distance (CLD) and other set-up parameters varied within 1 fraction about 1mm (1SD). The average variation of these parameters between various fractions was about 2 mm (1SD). The differences between simulator and treatment set-up over all patients and all fractions was on the average 2-3mm for the central beam edge to skin distance and CLD. It can be concluded that the tangential breast treatment set-up is very stable and reproducible and that respiration does not have a significant influence on treatment volume. EPID appears to be an adequate tool for studies of treatment set-up accuracy like this. (author). 35 refs.; 2 figs.; 3 tabs.

  10. 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.

  11. Use of acoustic vortices in acoustic levitation

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  12. Acoustic cryocooler

    Science.gov (United States)

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

    1990-01-01

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

  13. A Full-Size High-Temperature Superconducting Coil Employed in a Wind Turbine Generator Setup

    DEFF Research Database (Denmark)

    Song, Xiaowei (Andy); Mijatovic, Nenad; Kellers, Jürgen

    2017-01-01

    A and 143 A, respectively. When tested in the setup, the maximum temperature of the coil is controlled at 77 K and 40 K, and the I-V curves under both conditions are presented. It is found that the lower half coil that is closer to the stator has a smaller Ic due to a higher field level. The study......A full-size stationary experimental setup, which is a pole pair segment of a 2 MW high-temperature superconducting (HTS) wind turbine generator, has been built and tested under the HTS-GEN project in Denmark. The performance of the HTS coil is crucial to the setup, and further to the development...

  14. Acoustic telemetry.

    Energy Technology Data Exchange (ETDEWEB)

    Drumheller, Douglas Schaeffer; Kuszmaul, Scott S.

    2003-08-01

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

  15. Aero-acoustic modeling using large eddy simulation

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Sørensen, Jens Nørkær

    2007-01-01

    The splitting technique for aero-acoustic computations is extended to simulate three-dimensional flow and acoustic waves from airfoils. The aero-acoustic model is coupled to a sub-grid-scale turbulence model for Large-Eddy Simulations. In the first test case, the model is applied to compute laminar...

  16. Digital image compression for a 2f multiplexing optical setup

    Science.gov (United States)

    Vargas, J.; Amaya, D.; Rueda, E.

    2016-07-01

    In this work a virtual 2f multiplexing system was implemented in combination with digital image compression techniques and redundant information elimination. Depending on the image type to be multiplexed, a memory-usage saving of as much as 99% was obtained. The feasibility of the system was tested using three types of images, binary characters, QR codes, and grey level images. A multiplexing step was implemented digitally, while a demultiplexing step was implemented in a virtual 2f optical setup following real experimental parameters. To avoid cross-talk noise, each image was codified with a specially designed phase diffraction carrier that would allow the separation and relocation of the multiplexed images on the observation plane by simple light propagation. A description of the system is presented together with simulations that corroborate the method. The present work may allow future experimental implementations that will make use of all the parallel processing capabilities of optical systems.

  17. Neutron lifetime measurement on setups with gravitational trap

    Energy Technology Data Exchange (ETDEWEB)

    Serebrov, A. P., E-mail: serebrov@pnpi.spb.ru; Fomin, A. K.; Kharitonov, A. G.; Varlamov, V. E.; Kolomenskiy, E. A.; Krasnoshchekova, I. A.; Chechkin, A. V. [National Research Centre “Kurchatov Institute”, Petersburg Nuclear Physics Institute (Russian Federation)

    2016-01-15

    Currently, the best accuracy of neutron lifetime measurements has been attained in the experiment with a gravitational trap for ultracold neutrons (UCNs), performed at the Petersburg Nuclear Physics Institute (PNPI); the measured lifetime was 878.5 ± 0.8 s. A new setup with a big gravitational trap has been designed to continue the methods and approaches used in the previous experiment. It is planned to reduce the measurement error to 0.2 s, i.e., improve the existing accuracy by a factor of 4. The spectrometer was designed at PNPI and installed on the PF2/MAM beam at the Institute Laue–Langevin. Test experiments have been performed.

  18. The new cold neutron tomography set-up at SINQ

    CERN Document Server

    Baechler, S; Cauwels, P; Dierick, M; Jolie, J; Materna, T; Mondelaers, W

    2002-01-01

    A new cold neutron tomography set-up is operational at the neutron spallation source SINQ of the Paul Scherrer Institute (PSI) in Villigen, Switzerland. The detection system is based on a sup 6 LiF/ZnS:Ag conversion screen and a CCD camera. Several tests have been carried out to characterize the quality of the tomography system, such as homogeneity, reproducibility, L/D-ratio and spatial resolution. The high flux and the good efficiency of the detector lead to very short exposure times. Thus, a typical set of tomography scans can be performed in only 20 min. Then, 3D computed tomography objects were calculated using the filtered back-projection reconstruction method. Initial results of various samples show that cold neutron tomography can be a useful tool for industry, geology and dentistry. Furthermore, suitable applications can be found in the field of archaeology.

  19. A Demonstration of Underwater Bubble Capture by the Fundamental Acoustic Mode in Spherical Geometry

    Directory of Open Access Journals (Sweden)

    Umaporn KONTHARAK

    2008-01-01

    Full Text Available Nowadays, scientific demonstrations have become a crucial part of scientific learning. Acoustic waves are normally demonstrated in air via Kundt’s tube, but a physical demonstration for underwater acoustic waves is still lacking. In this paper, we address one of the aspects by demonstrating a way to acoustically-trap gas bubbles in a spherical, water-filled flask resonating at its first fundamental mode. The theory of acoustic waves in a spherical geometry, particularly the fundamental mode, is reviewed. The full description of the experimental setup is expressed both acoustically and electronically. By using this method, we show that a gas bubble can be stabilized in the middle of a flask at an acoustic frequency of 21.16 kHz, the acoustic fundamental frequency of the flask.

  20. Compact electrically detected magnetic resonance setup

    Directory of Open Access Journals (Sweden)

    Michael Eckardt

    2015-04-01

    Full Text Available Electrically detected magnetic resonance (EDMR is a commonly used technique for the study of spin-dependent transport processes in semiconductor materials and electro-optical devices. Here, we present the design and implementation of a compact setup to measure EDMR, which is based on a commercially available benchtop electron paramagnetic resonance (EPR spectrometer. The electrical detection part uses mostly off-the-shelf electrical components and is thus highly customizable. We present a characterization and calibration procedure for the instrument that allowed us to quantitatively reproduce results obtained on a silicon-based reference sample with a “large-scale” state-of-the-art instrument. This shows that EDMR can be used in novel contexts relevant for semiconductor device fabrication like clean room environments and even glove boxes. As an application example, we present data on a class of environment-sensitive objects new to EDMR, semiconducting organic microcrystals, and discuss similarities and differences to data obtained for thin-film devices of the same molecule.

  1. Setup verification in linac-based radiosurgery.

    Science.gov (United States)

    Falco, T; Lachaine, M; Poffenbarger, B; Podgorsak, E B; Fallone, B G

    1999-09-01

    A semi-automatic technique for the direct setup alignment of radiosurgical circular fields from an isocentric linac to treatment room laser cross-hairs is described. Alignment is achieved by acquiring images of the treatment room positioning laser cross-hairs superimposed on the radiosurgical circular field image. An alignment algorithm calculates the center of the radiosurgical field image as well as the intersection of the laser cross-hairs. This determines any alignment deviations and the information is then used to translate the radiosurgical collimator to its correct aligned position. Two detectors, each being sensitive to the lasers and ionizing radiation, were used to acquire the radiation/laser images. The first detector consists of a 0.3-mm-thick layer of photoconducting a-Se deposited on a 1.5-mm-thick copper plate and the second is film. The algorithm and detector system can detect deviations with a precision of approximately 0.04 mm. A device with gyroscopic degrees of freedom was built in order to firmly hold the detector at any orientation perpendicular to the radiosurgical beam axis. This device was used in conjunction with our alignment algorithm to quantify the isocentric sphere relative to the treatment room lasers over all gantry and couch angles used in dynamic stereotactic radiosurgery.

  2. Tests for acoustic propagation characteristics in drill string composed of size-difference drill pipes%尺寸差异钻杆组成的钻柱中声传播特性测试

    Institute of Scientific and Technical Information of China (English)

    刘永旺; 管志川; 赵国山; 杜彬彬; 李致远; 蔡孟哲; 都振川; 王庆

    2015-01-01

    The acoustic transmission of information,measured by MWD,is an important research direction of underground information wireless transmission technology.The drill string serving as information transmission channel was composed of size-difference drill pipes,so it is important to understand the relationship between the drill pipe size-difference and acoustic wave propagation characteristics in the column.That is related to the selection of sound carrier and detection measure.A test device for testing the drill string acoustic propagation characteristics was established,and relecant tests were carried out.The test results were analysed by using the model of sound propagation based on the acoustic permeable layer theory.The results show that:with the application of size-difference drill,the acoustic wave propagation characteristics of drill string will be changed,which behaves in the following aspects;the number of pass-bands reduces,some of the pass-bands disappear,and the pass-band width is narrowed;when acoustic waves propagate through the drill string composed of size-difference drill pipes,the attenuation is bigger than that through the cyclical drill. Less affected by differences in the drill pipe sizes are the low-frequency pass band acoustic waves;there is some arrangement with which the effect can be reduced.In the information carrier selection and testing,the impact of channel structure should be fully considered.The theoretical model of acoustic propagation is exact in the calculation of the first 4 pass-bands.%随钻实测信息声波传输技术是井下信息无线传输技术领域的一个重要研究方向。作为信息传输通道的钻柱是由尺寸存在差异的钻杆相连接构成,钻杆的尺寸差异对钻柱中声的传播是否存在影响是声载波选取及检测必须要了解的问题之一。建立了用于测试钻柱中声波传播特性的试验装置,对不同类型钻杆组成的钻柱中声波的传播特性进行了测试

  3. STRAIN LOCALIZATION PECULIARITIES AND DISTRIBUTION OF ACOUSTIC EMISSION SOURCES IN ROCK SAMPLES TESTED BY UNIAXIAL COMPRESSION AND EXPOSED TO ELECTRIC PULSES

    Directory of Open Access Journals (Sweden)

    V. A. Mubassarova

    2015-09-01

    Full Text Available Results of uniaxial compression tests of rock samples in electromagnetic fields are presented. The experiments were performed in the Laboratory of Basic Physics of Strength, Institute of Continuous Media Mechanics, Ural Branch of RAS (ICMM. Deformation of samples was studied, and acoustic emission (AE signals were recorded. During the tests, loads varied by stages. Specimens of granite from the Kainda deposit in Kyrgyzstan (similar to samples tested at the Research Station of RAS, hereafter RS RAS were subject to electric pulses at specified levels of compression load. The electric pulses supply was galvanic; two graphite electrodes were fixed at opposite sides of each specimen. The multichannel Amsy-5 Vallen System was used to record AE signals in the six-channel mode, which provided for determination of spatial locations of AE sources. Strain of the specimens was studied with application of original methods of strain computation based on analyses of optical images of deformed specimen surfaces in LaVISION Strain Master System.Acoustic emission experiment data were interpreted on the basis of analyses of the AE activity in time, i.e. the number of AE events per second, and analyses of signals’ energy and AE sources’ locations, i.e. defects.The experiment was conducted at ICMM with the use of the set of equipment with advanced diagnostic capabilities (as compared to earlier experiments described in [Zakupin et al., 2006a, 2006b; Bogomolov et al., 2004]. It can provide new information on properties of acoustic emission and deformation responses of loaded rock specimens to external electric pulses.The research task also included verification of reproducibility of the effect (AE activity when fracturing rates responded to electrical pulses, which was revealed earlier in studies conducted at RS RAS. In terms of the principle of randomization, such verification is methodologically significant as new effects, i.e. physical laws, can be considered

  4. Damage characterization of thermal barrier coatings by acoustic emission and thermography

    Energy Technology Data Exchange (ETDEWEB)

    Nies, Daniel; Rehmer, Birgit; Skrotzki, Birgit [BAM Federal Institute for Materials Research and Testing, Berlin (Germany); Vassen, Robert [Forschungszentrum Juelich, Juelich (Germany)

    2012-09-15

    Thermal barrier coatings allow increasing the operating temperature and efficiency of land-, sea-, or air-based turbines. As failure of the coating may result in serious damage of the turbine, reliable estimation of its lifetime is essential. To assess the lifetime, cyclic tests are conceived to combine thermal loading by heating the surface of the coating with laser irradiation and nondestructive methods for damage determination. Using laser irradiation allows a high reproducibility of the thermal load. The temperature of the sample surface during thermal loading is determined by an infrared-camera which also enables the possibility to detect damage in the coating via thermography. Additionally, four acoustic sensors, attached to the experimental setup, are used to detect damage in the sample and determine the source of acoustic events. Results of acoustic emission correlate well with thermographic images that visualize the formation and evolution of damage through delaminations in the samples. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Simple optical setup implementation for digital Fourier transform holography

    Energy Technology Data Exchange (ETDEWEB)

    De Oliveira, G N [Pos-graduacao em Engenharia Mecanica, TEM/PGMEC, Universidade Federal Fluminense, Rua Passo da Patria, 156, Niteroi, R.J., Cep.: 24.210-240 (Brazil); Rodrigues, D M C; Dos Santos, P A M, E-mail: pams@if.uff.br [Instituto de Fisica, Laboratorio de Optica Nao-linear e Aplicada, Universidade Federal Fluminense, Av. Gal. Nilton Tavares de Souza, s/n, Gragoata, Niteroi, R.J., Cep.:24.210-346 (Brazil)

    2011-01-01

    In the present work a simple implementation of Digital Fourier Transform Holography (DFTH) setup is discussed. This is obtained making a very simple modification in the classical setup arquiteture of the Fourier Transform holography. It is also demonstrated the easy and practical viability of the setup in an interferometric application for mechanical parameters determination. The work is also proposed as an interesting advanced introductory training for graduated students in digital holography.

  6. total completion time with random and bounded setup times

    Directory of Open Access Journals (Sweden)

    Ali Allahverdi

    2003-01-01

    Full Text Available This paper addresses the two-machine flowshop scheduling problem with separate setup times to minimize makespan or total completion time (TCT. Setup times are relaxed to be random variables rather than deterministic as commonly used in the OR literature. Moreover, distribution-free setup times are used where only the lower and upper bounds are given. Global and local dominance relations are developed for the considered flowshops and an illustrative numerical example is given.

  7. 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

  8. Test Study on Acoustic Emission Evolution Characteristics in Failure Process of Plastic and Brittle Coal%塑性煤与脆性煤破坏过程的声发射演化特征试验研究

    Institute of Scientific and Technical Information of China (English)

    杨慧明

    2015-01-01

    在单轴压缩条件下,进行了塑性煤与脆性煤试件破坏过程声发射监测试验,研究两类煤破坏过程的声发射演化特征。试验结果表明:煤体破坏失稳过程中的声发射与煤体中的裂纹萌生、扩展、贯通等活动相对应,煤体的声发射演化特征与其破坏特征密切相关。塑性煤破坏过程的声发射事件率呈现“上升—峰值—下降”的演化规律;声发射事件率出现急速增大之后的稳步下降是煤体主破裂面即将贯通、煤体破坏失稳的前兆。脆性煤破坏过程的声发射事件率呈现“上升—峰值”的演化规律,声发射“下降”段不明显。研究结果可为煤体稳定性监测的声发射参数演化的解译、灾变判识准则的建立提供理论基础。%Under the condition of uniaxial compression, monitoring test of acoustic emission was carried out in the failure process of both plastic and brittle coal specimen and study was made on the evolution characteristics of acoustic emission in their failure process. The test results showed that the acoustic emission in the failure and destabilizing process of coal corresponded with the process of crack initiation,extension and interconnection in the coal,and the evolution characteristics of acoustic emission of coal were closely related to its failure characteristics. The acoustic emission event rate in the failure process of the plastic coal presented an evolution regularity of “up-peak-down”;the steady decrease of the acoustic emission event rate after its rapid increase was the precursor of the main fracture surface connection and the failure and destabilization of coal. The acoustic emission event rate of the brittle coal presented an evolution regularity of “up-peak” and the “down” stage of acoustic emission was not obvious. The study results can provide a theoretical basis for the explanations of the acoustic emission parameter evolution in coal stability

  9. The compact and inexpensive arrowhead setup for holographic interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Ladera, Celso L; Donoso, Guillermo, E-mail: clladera@usb.v [Departamento de Fisica, Universidad Simon BolIvar, Apdo. 89000, Caracas 1086 (Venezuela, Bolivarian Republic of)

    2011-07-15

    Hologram recording and holographic interferometry are intrinsically sensitive to phase changes, and therefore both are easily perturbed by minuscule optical path perturbations. It is therefore very convenient to bank on holographic setups with a reduced number of optical components. Here we present a compact off-axis holographic setup that requires neither a collimator nor a beam-splitter, and whose layout is reminiscent of an arrowhead. We show that this inexpensive setup is a good alternative for the study and applications of scientific holography by measuring small displacements and deformations of a body. The arrowhead setup will be found particularly useful for holography and holographic interferometry experiments and projects in teaching laboratories.

  10. Wind turbine acoustics

    Science.gov (United States)

    Hubbard, Harvey H.; Shepherd, Kevin P.

    1990-12-01

    Available information on the physical characteristics of the noise generated by wind turbines is summarized, with example sound pressure time histories, narrow- and broadband frequency spectra, and noise radiation patterns. Reviewed are noise measurement standards, analysis technology, and a method of characterizing wind turbine noise. Prediction methods are given for both low-frequency rotational harmonics and broadband noise components. Also included are atmospheric propagation data showing the effects of distance and refraction by wind shear. Human perception thresholds, based on laboratory and field tests, are given. Building vibration analysis methods are summarized. The bibliography of this report lists technical publications on all aspects of wind turbine acoustics.

  11. Boundary acquisition for setup of numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Diegert, C. [Sandia National Lab., Albuquerque, NM (United States)

    1997-12-31

    The author presents a work flow diagram that includes a path that begins with taking experimental measurements, and ends with obtaining insight from results produced by numerical simulation. Two examples illustrate this path: (1) Three-dimensional imaging measurement at micron scale, using X-ray tomography, provides information on the boundaries of irregularly-shaped alumina oxide particles held in an epoxy matrix. A subsequent numerical simulation predicts the electrical field concentrations that would occur in the observed particle configurations. (2) Three-dimensional imaging measurement at meter scale, again using X-ray tomography, provides information on the boundaries fossilized bone fragments in a Parasaurolophus crest recently discovered in New Mexico. A subsequent numerical simulation predicts acoustic response of the elaborate internal structure of nasal passageways defined by the fossil record. The author must both add value, and must change the format of the three-dimensional imaging measurements before the define the geometric boundary initial conditions for the automatic mesh generation, and subsequent numerical simulation. The author applies a variety of filters and statistical classification algorithms to estimate the extents of the structures relevant to the subsequent numerical simulation, and capture these extents as faceted geometries. The author will describe the particular combination of manual and automatic methods used in the above two examples.

  12. 热环境下金属壁板噪声激励动响应试验研究%Dynamic response tests of metallic panels excited by acoustic loads in thermal environment

    Institute of Scientific and Technical Information of China (English)

    吴振强; 李海波; 程昊; 郭静; 张伟

    2016-01-01

    Metallic panels are major structural components for thermal protection system of hypersonic vehicles, which are exposed to a severe combination of aerodynamic, thermal and acoustic environments during cruise or re-entry flights. It presents a significant challenge for the integrity and the durability for these structures. Titanium flat and stiffened panels are designed. Then, a series of dynamic response tests of these panels are carried out using a thermal-acoustic apparatus. The temperature of the testing panel is up to 400℃and the exciting acoustic load is over 162 dB. Dynamic responses of these testing panels are measured using high temperature accelerometer and strain gauge during the testing process. Results show that the maximal root mean square (RMS) acceleration values of the flat plate and stiffened panel are approximate to 94.5g and 199.0g, respectively. It is shown that the dynamic RMS values are dominated by sound pressure level of acoustic loads. However, the thermal environment has more effects on the power spectral density distribution than the RMS values of dynamic response excited by acoustic loads.%高超声速飞行器热防护系统包含多种形式的金属壁板结构,巡航或再入过程中经历着严酷的气动热、气动力、噪声等复合环境,严重威胁着飞行器结构的完整性和可靠性。为评估壁板结构的耐噪声性能,设计了钛合金平板和加筋板试验件,采用热噪声试验系统开展了试验件中心温度最高为400℃、噪声最高为162dB的动响应试验,采用高温加速度计和高温应变片对动态响应进行了测试。结果表明,钛合金平板和加筋板的最大加速度均方根值分别可达94.5 g和199.0g,金属壁板动态响应均方根值与噪声量级密切相关,受热环境影响较小,而热环境显著改变了动态响应的频谱分布。

  13. 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...

  14. Acoustically-Induced Electrical Signals

    Science.gov (United States)

    Brown, S. R.

    2014-12-01

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

  15. 声发射技术在抽杆疲劳实验中的应用%Application of acoustic emission (AE) technique in crack monitor during fatigue test of pump rods

    Institute of Scientific and Technical Information of China (English)

    夏永发; 李海玲

    2007-01-01

    The acoustic emission(AE)real time monitoring of fatigue damage of pump rods samples during fatigue test was introduced.Under severe environmental noise caused by vibration,the real time monitoring of the fatigue crack initiation and expansion was realized successfully by using the parameters analysis method combined by AE Hits and Amplitude.The characters of the methods are simple and real time,which can provide a more accurate and impersonal basis for judging whether the fatigue test piece has been destroyed,thus can provide a scientific assistant method for accurately determining the life of pump rod.

  16. Diagnostic Setup for Characterization of Near-Anode Processes in Hall Thrusters

    Energy Technology Data Exchange (ETDEWEB)

    L. Dorf; Y. Raitses; N.J. Fisch

    2003-09-08

    A diagnostic setup for characterization of near-anode processes in Hall-current plasma thrusters consisting of biased and emissive electrostatic probes, high-precision positioning system and low-noise electronic circuitry was developed and tested. Experimental results show that radial probe insertion does not cause perturbations to the discharge and therefore can be used for accurate near-anode measurements.

  17. Analysis of acoustic emission signals of fatigue crack growth and corrosion processes. Investigation of the possibilities for continuous condition monitoring of transport containers by acoustic emission testing; Analyse der Schallemissionssignale aus Ermuedungsrisswachstum und Korrosionsprozessen. Untersuchung der Moeglichkeiten fuer die kontinuierliche Zustandsueberwachung von Transportbehaeltern mittels Schallemissionspruefung

    Energy Technology Data Exchange (ETDEWEB)

    Wachsmuth, Janne

    2016-05-01

    Fatigue crack growth and active corrosion processes are the main causes of structural failures of transport products like road tankers, railway tank cars and ships. To prevent those failures, preventive, time-based maintenance is performed. However, preventive inspections are costly and include the risk of not detecting a defect, which could lead to a failure within the next service period. An alternative is the idea of continuous monitoring of the whole structure by means of acoustic emission testing (AT). With AT, defects within the material shall be detected and repaired directly after their appearance. Acoustic emission testing is an online non-destructive testing method. Acoustic emission (AE) arises from changes within the material and is transported by elastic waves through the material. If the AE event generates enough energy, the elastic wave propagates to the boundaries of the component, produces a displacement in the picometre scale and can be detected by a piezoelectric sensor. The sensor produces an electrical signal. From this AE signal, AE features such as the maximum amplitude or the frequency can be extracted. Methods of signal analysis are used to investigate the time and frequency dependency of signal groups. The purpose of the signal analysis is to connect the AE signal with the originating AE source. If predefined damage mechanisms are identified, referencing the damage condition of the structure is possible. Acoustic emission from events of the actual crack propagation process can for example lead to the crack growth rate or the stress intensity factor, both specific values from fracture mechanics. A new development in the domain of acoustic emission testing is the pattern recognition of AE signals. Specific features are extracted from the AE signals to assign them to their damage mechanisms. In this thesis the AE signals from the damage mechanisms corrosion and fatigue crack growth are compared and analysed. The damage mechanisms were

  18. Set-Up on the Basis of Multiwire Proportional and Ionization Chambers for Radioactive Beam Experiments

    CERN Document Server

    Astabatyan, R A; Kavalov, R L; Kugler, A; Kuznetsov, I V; Kushniruk, V F; Lobastov, S P; Lukyanov, S M; Markaryan, E R; Maslov, V A; Mikhailov, L; Penionzhkevich, Yu E; Poroshin, N O; Skobelev, N K; Smirnov, V I; Sobolev, Yu G; Ugryumov, V Yu

    2002-01-01

    A large-aperture set-up designed for nuclear physics experiments on beams of radioactive nuclei is described. The set-up includes Multiwire Proportional Chamber (MWPC) for measuring the beam profile, MWPC for measuring reaction product angular distributions, a CsI(Tl)-crystal detector and a longitudinal drift ionization chamber for identifying scattered particles and measuring their energy. The results of tests of coordinate MWPCs, particle identification on photon and ion beams, and preliminary measurements of the elastic scattering and the charge exchange reaction of 170 MeV ^{6}He on a CH_{2} target are presented.

  19. Acoustic Spatiality

    Directory of Open Access Journals (Sweden)

    Brandon LaBelle

    2012-06-01

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

  20. 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.

  1. Commissioning and quality assurance of an integrated system for patient positioning and setup verification in particle therapy.

    Science.gov (United States)

    Pella, A; Riboldi, M; Tagaste, B; Bianculli, D; Desplanques, M; Fontana, G; Cerveri, P; Seregni, M; Fattori, G; Orecchia, R; Baroni, G

    2014-08-01

    In an increasing number of clinical indications, radiotherapy with accelerated particles shows relevant advantages when compared with high energy X-ray irradiation. However, due to the finite range of ions, particle therapy can be severely compromised by setup errors and geometric uncertainties. The purpose of this work is to describe the commissioning and the design of the quality assurance procedures for patient positioning and setup verification systems at the Italian National Center for Oncological Hadrontherapy (CNAO). The accuracy of systems installed in CNAO and devoted to patient positioning and setup verification have been assessed using a laser tracking device. The accuracy in calibration and image based setup verification relying on in room X-ray imaging system was also quantified. Quality assurance tests to check the integration among all patient setup systems were designed, and records of daily QA tests since the start of clinical operation (2011) are presented. The overall accuracy of the patient positioning system and the patient verification system motion was proved to be below 0.5 mm under all the examined conditions, with median values below the 0.3 mm threshold. Image based registration in phantom studies exhibited sub-millimetric accuracy in setup verification at both cranial and extra-cranial sites. The calibration residuals of the OTS were found consistent with the expectations, with peak values below 0.3 mm. Quality assurance tests, daily performed before clinical operation, confirm adequate integration and sub-millimetric setup accuracy. Robotic patient positioning was successfully integrated with optical tracking and stereoscopic X-ray verification for patient setup in particle therapy. Sub-millimetric setup accuracy was achieved and consistently verified in daily clinical operation.

  2. Acoustic clouds: standing sound waves around a black hole analogue

    CERN Document Server

    Benone, Carolina L; Herdeiro, Carlos; Radu, Eugen

    2014-01-01

    Under certain conditions sound waves in fluids experience an acoustic horizon with analogue properties to those of a black hole event horizon. In particular, a draining bathtub-like model can give rise to a rotating acoustic horizon and hence a rotating black hole (acoustic) analogue. We show that sound waves, when enclosed in a cylindrical cavity, can form stationary waves around such rotating acoustic black holes. These acoustic perturbations display similar properties to the scalar clouds that have been studied around Kerr and Kerr-Newman black holes; thus they are dubbed acoustic clouds. We make the comparison between scalar clouds around Kerr black holes and acoustic clouds around the draining bathtub explicit by studying also the properties of scalar clouds around Kerr black holes enclosed in a cavity. Acoustic clouds suggest the possibility of testing, experimentally, the existence and properties of black hole clouds, using analog models.

  3. Design considerations and sensitivity estimates for an acoustic neutrino detector

    CERN Document Server

    Karg, T; Graf, K; Hoessl, J; Kappes, A; Katz, U; Lahmann, R; Naumann, C; Salomon, K; Karg, Timo; Anton, Gisela; Graf, Kay; Hoessl, Juergen; Kappes, Alexander; Katz, Uli; Lahmann, Robert; Naumann, Christopher; Salomon, Karsten

    2005-01-01

    We present a Monte Carlo study of an underwater neutrino telescope based on the detection of acoustic signals generated by neutrino induced cascades. This provides a promising approach to instrument large detector volumes needed to detect the small flux of cosmic neutrinos at ultra-high energies (E > 1 EeV). Acoustic signals are calculated based on the thermo-acoustic model. The signal is propagated to the sensors taking frequency dependent attenuation into account, and detected using a threshold trigger, where acoustic background is included as an effective detection threshold. A simple reconstruction algorithm allows for the determination of the cascade direction and energy. Various detector setups are compared regarding their effective volumes. Sensitivity estimates for the diffuse neutrino flux are presented.

  4. Laser Imaging of Airborne Acoustic Emission by Nonlinear Defects

    Science.gov (United States)

    Solodov, Igor; Döring, Daniel; Busse, Gerd

    2008-06-01

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

  5. A compact multi-chamber setup for degradation and lifetime studies of organic solar cells

    DEFF Research Database (Denmark)

    Gevorgyan, Suren; Jørgensen, Mikkel; Krebs, Frederik C;

    2011-01-01

    A controlled atmosphere setup designed for long-term degradation studies of organic solar cells under illumination is presented. The setup was designed with ease-of-use and compactness in mind and allows for multiple solar cells distributed on four glass substrates to be studied in four different...... chambers with temperature and atmosphere control. The four chambers are situated at close proximity in the setup thereby allowing the solar cells to be subjected to as uniform an illumination distribution as possible for the given solar simulator employed. The cell substrates serve as the front window...... and present a tight seal. Hence no illumination correction needs to be performed due to transmission and reflection losses as otherwise seen with test chambers employing a window as a seal. The solar cells in each chamber are continuously and individually electrically monitored under biased conditions...

  6. 1 {\\Omega}-10 k{\\Omega} high precision transportable setup to calibrate multifunction electrical instruments

    CERN Document Server

    Capra, P P

    2015-01-01

    A temperature controlled 1 {\\Omega}-10 k{\\Omega} standard Resistors transportable setup was developed at National Institute of Metrological Research, (INRIM) for the calibration and adjustment of multifunction electrical instruments. The two Standards consist respectively of two 10 {\\Omega} and 100 k{\\Omega} parallel connected resistors nets inserted in a temperature controlled aluminium box. Novelty of the realization is the oil insertion of the 1 {\\Omega} net with its internal connectors lowering the thermo-electromotive forces (emfs) effects. Short and mid-term stabilities of the setup Standards resulted on the order and in some cases better than other top level 1 {\\Omega} and 10 k{\\Omega} commercial Standards. The transport effect turning off the setup temperature control did not cause appreciable measurement deviations on the two Standards. The Standards uncertainties meet those requested by DMMs and MFCs manufacturers to calibrate and adjust these instruments. A test to adjust a multifunction calibrator...

  7. Acoustic neuroma

    Science.gov (United States)

    ... 30. Common symptoms include: Abnormal feeling of movement ( vertigo ) Hearing loss in the affected ear that makes ... it apart from other causes of dizziness or vertigo include: Hearing test Test of equilibrium and balance ( ...

  8. Acoustic source for generating an acoustic beam

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-05-31

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

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

    Science.gov (United States)

    Shen, Jian Qi

    2016-08-01

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

  10. Strength Restoration of Cracked Sandstone and Coal under a Uniaxial Compression Test and Correlated Damage Source Location Based on Acoustic Emissions.

    Directory of Open Access Journals (Sweden)

    Xiaowei Feng

    Full Text Available Underground rock masses have shown a general trend of natural balance over billions of years of ground movement. Nonetheless, man-made underground constructions disturb this balance and cause rock stability failure. Fractured rock masses are frequently encountered in underground constructions, and this study aims to restore the strength of rock masses that have experienced considerable fracturing under uniaxial compression. Coal and sandstone from a deep-buried coal mine were chosen as experimental subjects; they were crushed by uniaxial compression and then carefully restored by a chemical adhesive called MEYCO 364 with an innovative self-made device. Finally, the restored specimens were crushed once again by uniaxial compression. Axial stress, axial strain, circumferential strain, and volumetric strain data for the entire process were fully captured and are discussed here. An acoustic emission (AE testing system was adopted to cooperate with the uniaxial compression system to provide better definitions for crack closure thresholds, crack initiation thresholds, crack damage thresholds, and three-dimensional damage source locations in intact and restored specimens. Several remarkable findings were obtained. The restoration effects of coal are considerably better than those of sandstone because the strength recovery coefficient of the former is 1.20, whereas that of the latter is 0.33, which indicates that MEYCO 364 is particularly valid for fractured rocks whose initial intact peak stress is less than that of MEYCO 364. Secondary cracked traces of restored sandstone almost follow the cracked traces of the initial intact sandstone, and the final failure is mainly caused by decoupling between the adhesive and the rock mass. However, cracked traces of restored coal only partially follow the traces of intact coal, with the final failure of the restored coal being caused by both bonding interface decoupling and self-breakage in coal. Three

  11. Modeling and simulation of LHC beam-based collimator setup

    CERN Document Server

    Valentino, G; Assmann, R W; Burkart, F; Redaelli, S; Rossi, A; Lari, L

    2012-01-01

    In the 2011 Large Hadron Collider run, collimators were aligned for proton and heavy ion beams using a semiautomatic setup algorithm. The algorithm provided a reduction in the beam time required for setup, an elimination of beam dumps during setup and better reproducibility with respect to manual alignment. A collimator setup simulator was developed based on a Gaussian model of the beam distribution as well as a parametric model of the beam losses. A time-varying beam loss signal can be simulated for a given collimator movement into the beam. The simulation results and comparison to measurement data obtained during collimator setups and dedicated fills for beam halo scraping are presented. The simulator will then be used to develop a fully automatic collimator alignment algorithm.

  12. Image processing techniques for acoustic images

    Science.gov (United States)

    Murphy, Brian P.

    1991-06-01

    The primary goal of this research is to test the effectiveness of various image processing techniques applied to acoustic images generated in MATLAB. The simulated acoustic images have the same characteristics as those generated by a computer model of a high resolution imaging sonar. Edge detection and segmentation are the two image processing techniques discussed in this study. The two methods tested are a modified version of the Kalman filtering and median filtering.

  13. Acoustic-Seismic Coupling in Porous Ground - Measurements and Analysis for On-Site-Inspection Support

    Science.gov (United States)

    Liebsch, Mattes; Gorschlüter, Felix; Altmann, Jürgen

    2014-05-01

    During on-site inspections (OSI) of the Comprehensive Nuclear Test Ban Treaty Organisation (CTBTO) a local seismic network can be installed to measure seismic aftershock signals of an assumed underground nuclear explosion. These signals are caused by relaxation processes in and near the cavity created by the explosion and when detected can lead to a localisation of the cavity. This localisation is necessary to take gas samples from the ground which are analysed for radioactive noble gas isotopes to confirm or dismiss the suspicion of a nuclear test. The aftershock signals are of very low magnitude so they can be masked by different sources, in particular periodic disturbances caused by vehicles and aircraft in the inspection area. Vehicles and aircraft (mainly helicopters) will be used for the inspection activities themselves, e.g. for overhead imagery or magnetic-anomaly sensing. While vehicles in contact with the ground can excite soil vibrations directly, aircraft and vehicles alike emit acoustic waves which excite soil vibrations when hitting the ground. These disturbing signals are of periodic nature while the seismic aftershock signals are pulse-shaped, so their separation is possible. The understanding of the coupling of acoustic waves to the ground is yet incomplete, a better understanding is necessary to improve the performance of an OSI, e.g. to address potential consequences for the sensor placement, the helicopter trajectories etc. In a project funded by the Young Scientist Research Award of the CTBTO to one of us (ML), we investigated the acoustic-seismic coupling of airborne signals of jet aircraft and artificially induced ones by a speaker. During a measurement campaign several acoustic and seismic sensors were placed below the take-off trajectory of an airport at 4 km distance. Therefore taking off and landing jet aircraft passed nearly straightly above the setup. Microphones were placed close to the ground to record the sound pressure of incident

  14. Liquid rocket combustion chamber acoustic characterization

    Directory of Open Access Journals (Sweden)

    Cândido Magno de Souza

    2010-09-01

    Full Text Available Over the last 40 years, many solid and liquid rocket motors have experienced combustion instabilities. Among other causes, there is the interaction of acoustic modes with the combustion and/or fluid dynamic processes inside the combustion chamber. Studies have been showing that, even if less than 1% of the available energy is diverted to an acoustic mode, combustion instability can be generated. On one hand, this instability can lead to ballistic pressure changes, couple with other propulsion systems such as guidance or thrust vector control, and in the worst case, cause motor structural failure. In this case, measures, applying acoustic techniques, must be taken to correct/minimize these influences on the combustion. The combustion chamber acoustic behavior in operating conditions can be estimated by considering its behavior in room conditions. In this way, acoustic tests can be easily performed, thus identifying the cavity modes. This paper describes the procedures to characterize the acoustic behavior in the inner cavity of four different configurations of a combustion chamber. Simple analytical models are used to calculate the acoustic resonance frequencies and these results are compared with acoustic natural frequencies measured at room conditions. Some comments about the measurement procedures are done, as well as the next steps for the continuity of this research. The analytical and experimental procedures results showed good agreement. However, limitations on high frequency band as well as in the identification of specific kinds of modes indicate that numerical methods able to model the real cavity geometry and an acoustic experimental modal analysis may be necessary for a more complete analysis. Future works shall also consider the presence of passive acoustic devices such as baffles and resonators capable of introducing damping and avoiding or limiting acoustic instabilities.

  15. Visualizing acoustical beats with a smartphones

    CERN Document Server

    Giménez, Marcos H; Castro-Palacio, Juan C; Gómez-Tejedor, José A; Monsoriu, Juan A

    2016-01-01

    In this work, a new Physics laboratory experiment on Acoustics beats is presented. We have designed a simple experimental setup to study superposition of sound waves of slightly different frequencies (acoustic beat). The microphone of a smartphone is used to capture the sound waves emitted by two equidistant speakers from the mobile which are at the same time connected to two AC generators. The smartphone is used as a measuring instrument. By means of a simple and free AndroidTM application, the sound level (in dB) as a function of time is measured and exported to a .csv format file. Applying common graphing analysis and a fitting procedure, the frequency of the beat is obtained. The beat frequencies as obtained from the smartphone data are compared with the difference of the frequencies set at the AC generator. A very good agreement is obtained being the percentage discrepancies within 1 %.

  16. Detecting and identifying damage in sandwich polymer composite by using acoustic emission

    DEFF Research Database (Denmark)

    McGugan, M.; Sørensen, Bent F.; Østergaard, R.;

    2006-01-01

    Acoustic emission is a useful monitoring tool for extracting extra information during mechanical testing of polymer composite sandwich materials. The study of fracture mechanics within test specimens extracted from wind turbine blade material ispresented. The contribution of the acoustic emission...

  17. Acoustic propagation in a rigid torus

    Science.gov (United States)

    El-Raheb, M.; Wagner, P.

    1982-01-01

    The acoustic propagation in a rigid torus is analyzed using a Green's function method. Three types of surface elements are developed; a flat quadrilateral element used in modeling polygonal cavities, a curved conical element appropriate for surfaces with one curvature, and a toroidal element developed for such doubly curved surfaces as the torus. Curved elements are necessary since the acoustic pressure is sensitive to slope discontinuities between consecutive surface elements especially near cavity resonances. The acoustic characteristics of the torus are compared to those of a bend of square cross section for a frequency range that includes the transverse acoustic resonance. Two equivalences between the different sections are tested; the first conserves curvature and cross-sectional dimension while the second matches transverse resonance and duct volume. The second equivalence accurately matches the acoustic characteristics of the torus up to the cutoff frequency corresponding to a mode with two circumferential waves.

  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 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

  20. Developing a beta source based setup for pixel sensor characterization

    CERN Document Server

    Schouwenberg, Jeroen

    2014-01-01

    The main goal of this project is to provide mono-energetic minimum ionizing electrons from a $^{90}$Sr source using a magnetic monochromator, and thus provide a useful tool for in-lab sensor characterization. The monochromator is calibrated using a setup, with a heavy inorganic scintillator and a PMT, which has been calibrated with a $^{22}$Na gamma source. The average energy of the electrons as a function of the current in the monochromator coil is found to be $1.38\\pm0.01$ keV/mA, taking into consideration the effect of the magnetic field on the signal of the PMT. For integration into the pixel sensor test bench, scintillator-counters (a plastic scintillator connected to a PMT) are used. Their response to the electron energies is observed to follow a saturation curve, which leads to a more identical response for high energetic electrons. A preliminary pixel sensor test bench has been set up and properties such as voltage and discriminator settings have been studied as well as count rates for coincidence cou...

  1. Acoustic Communications (ACOMMS) ATD

    Science.gov (United States)

    2016-06-14

    develop and demonstrate emerging undersea acoustic communication technologies at operationally useful ranges and data rates. The secondary objective...Technology Demonstration program (ACOMMS ATD) was to demonstrate long range and moderate data rate underwater acoustic communications between a submarine...moderate data rate acoustic communications capability for tactical use between submarines, surface combatants, unmanned undersea vehicles (UUVs), and other

  2. 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).

  3. High-resolution continuous flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

    Science.gov (United States)

    Emanuelsson, B. D.; Baisden, W. T.; Bertler, N. A. N.; Keller, E. D.; Gkinis, V.

    2014-12-01

    Here we present an experimental setup for water stable isotopes (δ18O and δD) continuous flow measurements. It is the first continuous flow laser spectroscopy system that is using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS; analyzer manufactured by Los Gatos Research - LGR) in combination with an evaporation unit to continuously analyze sample from an ice core. A Water Vapor Isotopic Standard Source (WVISS) calibration unit, manufactured by LGR, was modified to: (1) increase the temporal resolution by reducing the response time (2) enable measurements on several water standards, and (3) to reduce the influence from memory effects. While this setup was designed for the Continuous Flow Analysis (CFA) of ice cores, it can also continuously analyze other liquid or vapor sources. The modified setup provides a shorter response time (~54 and 18 s for 2013 and 2014 setup, respectively) compared to the original WVISS unit (~62 s), which is an improvement in measurement resolution. Another improvement compared to the original WVISS is that the modified setup has a reduced memory effect. Stability tests comparing the modified WVISS and WVISS setups were performed and Allan deviations (σAllan) were calculated to determine precision at different averaging times. For the 2013 modified setup the precision after integration times of 103 s are 0.060 and 0.070‰ for δ18O and δD, respectively. For the WVISS setup the corresponding σAllan values are 0.030, 0.060 and 0.043‰ for δ18O, δD and δ17O, respectively. For the WVISS setup the precision is 0.035, 0.070 and 0.042‰ after 103 s for δ18O, δD and δ17O, respectively. Both the modified setups and WVISS setup are influenced by instrumental drift with δ18O being more drift sensitive than δD. The σAllan values for δ18O of 0.30 and 0.18‰ for the modified (2013) and WVISS setup, respectively after averaging times of 104 s (2.78 h). The Isotopic Water Analyzer (IWA)-modified WVISS setup used during the

  4. High-resolution continuous flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

    Directory of Open Access Journals (Sweden)

    B. D. Emanuelsson

    2014-12-01

    Full Text Available Here we present an experimental setup for water stable isotopes (δ18O and δD continuous flow measurements. It is the first continuous flow laser spectroscopy system that is using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS; analyzer manufactured by Los Gatos Research – LGR in combination with an evaporation unit to continuously analyze sample from an ice core. A Water Vapor Isotopic Standard Source (WVISS calibration unit, manufactured by LGR, was modified to: (1 increase the temporal resolution by reducing the response time (2 enable measurements on several water standards, and (3 to reduce the influence from memory effects. While this setup was designed for the Continuous Flow Analysis (CFA of ice cores, it can also continuously analyze other liquid or vapor sources. The modified setup provides a shorter response time (~54 and 18 s for 2013 and 2014 setup, respectively compared to the original WVISS unit (~62 s, which is an improvement in measurement resolution. Another improvement compared to the original WVISS is that the modified setup has a reduced memory effect. Stability tests comparing the modified WVISS and WVISS setups were performed and Allan deviations (σAllan were calculated to determine precision at different averaging times. For the 2013 modified setup the precision after integration times of 103 s are 0.060 and 0.070‰ for δ18O and δD, respectively. For the WVISS setup the corresponding σAllan values are 0.030, 0.060 and 0.043‰ for δ18O, δD and δ17O, respectively. For the WVISS setup the precision is 0.035, 0.070 and 0.042‰ after 103 s for δ18O, δD and δ17O, respectively. Both the modified setups and WVISS setup are influenced by instrumental drift with δ18O being more drift sensitive than δD. The σAllan values for δ18O of 0.30 and 0.18‰ for the modified (2013 and WVISS setup, respectively after averaging times of 104 s (2.78 h. The Isotopic Water Analyzer (IWA-modified WVISS setup used

  5. An Improved Automated Setup for Solubility Determination of Drugs

    Directory of Open Access Journals (Sweden)

    Ahmad Ghanbari 1, Yashar Sarbaz, Vahid Jouyban-Gharamaleki, Karim Jouyban-Gharamaleki, Jafar Soleymani, Abolghasem Jouyban

    2016-09-01

    Full Text Available Background: Solubility of a drug/drug candidate is an essential information in the pharmaceutical area. Classical solubility determination method used in the laboratories are expensive and time-consuming. Attempts were made to provide an automated solubility determination setup based on a laser monitoring technique. Methods: In a previously developed setup, drug powder was added to a given quantity of the solvent which made some troubles in practical applications. The present work reports another setup which adds solvent to a given mass of the drug. The validity of the measured solubilities is checked by comparing the measured solubilities of acetaminophen at two temperatures in water and ethanol mixtures with the corresponding data from the literature. Results: The results reveal that the improved setup could overcome the limitations of the previously developed setup and could be used for drug solubility determination. Conclusion: The improved setup overcomes the troubles made in the previous setup and could be used in generating large amount of solubility data to be used in the pharmaceutical industry.

  6. Integration of micro milling highspeed spindle on a microEDM-milling machine set-up

    DEFF Research Database (Denmark)

    De Grave, Arnaud; Hansen, Hans Nørgaard; Andolfatto, Loic

    2009-01-01

    In order to cope with repositioning errors and to combine the fast removal rate of micro milling with the precision and small feature size achievable with micro EDM milling, a hybrid micro-milling and micro-EDM milling centre was built and tested. The aim was to build an affordable set-up, easy...... by micro milling. Examples of test parts are shown and used as an experimental validation....

  7. Acoustic behaviors of unsaturated soils

    Science.gov (United States)

    Lu, Z.

    2011-12-01

    Soils are unconsolidated granular materials, consisting of solid particles, water and air. Their mechanical and dynamic behaviors are determined by the discrete nature of the media as well as external and inter-particle forces. For unsaturated soils, two factors significantly affect soils acoustic/seismic responses: external pressure and internal water potential/matric suction. In triaxial cell tests, unsaturated soils were subjected to predefined stress paths to undergo stages of normal consolidation, unload-reload cycles, and failure. The stress deformation curve and stress-P-wave velocity were measured and compared. The study revealed that soil's dynamic response to external pressure are similar to those of the load-deformation behaviors and demonstrated that acoustic velocity can be used to monitor the state of stress of soils. In a long term field soil survey, the P-wave velocities were found to be correlated with water potential as expressed as a power-law relationship. The above phenomena can be understood by using the Terzaghi' s the principle of effective stress. The measured results were in good agreement with Brutsaert theory. The effective stress concept can also be applied to explain the observations in a soil pipe flow study in which soil internal erosion processes were monitored and interpreted by the temporal evolution of the P-wave velocity. In addition to above linear acoustic behaviors, soils, like other earth materials, exhibit astonishing non-classical nonlinear behaviors such as end-point memory, hysteresis, strain -dependent shear modulus, resonant frequency shift, and phase shift, harmonics generation, etc. A nonlinear acoustic study of a soil as a function of water content showed that the nonlinear acoustic parameter are much sensitive to the variations of soil water content than that of the acoustic velocity.

  8. Acoustic Emission of Deformation Twinning in Magnesium

    Directory of Open Access Journals (Sweden)

    Chengyang Mo

    2016-08-01

    Full Text Available The Acoustic Emission of deformation twinning in Magnesium is investigated in this article. Single crystal testing with combined full field deformation measurements, as well as polycrystalline testing inside the scanning electron microscope with simultaneous monitoring of texture evolution and twin nucleation were compared to testing at the laboratory scale with respect to recordings of Acoustic Emission activity. Single crystal testing revealed the formation of layered twin boundaries in areas of strain localization which was accompanied by distinct changes in the acoustic data. Testing inside the microscope directly showed twin nucleation, proliferation and growth as well as associated crystallographic reorientations. A post processing approach of the Acoustic Emission activity revealed the existence of a class of signals that appears in a strain range in which twinning is profuse, as validated by the in situ and ex situ microscopy observations. Features extracted from such activity were cross-correlated both with the available mechanical and microscopy data, as well as with the Acoustic Emission activity recorded at the laboratory scale for similarly prepared specimens. The overall approach demonstrates that the method of Acoustic Emission could provide real time volumetric information related to the activation of deformation twinning in Magnesium alloys, in spite of the complexity of the propagation phenomena, the possible activation of several deformation modes and the challenges posed by the sensing approach itself when applied in this type of materials evaluation approach.

  9. Applied acoustics concepts, absorbers, and silencers for acoustical comfort and noise control alternative solutions, innovative tools, practical examples

    CERN Document Server

    Fuchs, Helmut V

    2013-01-01

    The author gives a comprehensive overview of materials and components for noise control and acoustical comfort. Sound absorbers must meet acoustical and architectural requirements, which fibrous or porous material alone can meet. Basics and applications are demonstrated, with representative examples for spatial acoustics, free-field test facilities and canal linings. Acoustic engineers and construction professionals will find some new basic concepts and tools for developments in order to improve acoustical comfort. Interference absorbers, active resonators and micro-perforated absorbers of different materials and designs complete the list of applications.

  10. Four point bending setup for characterization of semiconductor piezoresistance

    DEFF Research Database (Denmark)

    Richter, Jacob; Arnoldus, Morten Berg; Hansen, Ole

    2008-01-01

    We present a four point bending setup suitable for high precision characterization of piezoresistance in semiconductors. The compact setup has a total size of 635 cm3. Thermal stability is ensured by an aluminum housing wherein the actual four point bending fixture is located. The four point...... bending fixture is manufactured in polyetheretherketon and a dedicated silicon chip with embedded piezoresistors fits in the fixture. The fixture is actuated by a microstepper actuator and a high sensitivity force sensor measures the applied force on the fixture and chip. The setup includes heaters...

  11. Structural health condition monitoring of rails using acoustic emission techniques

    Science.gov (United States)

    Yilmazer, Pinar

    In-service rails can develop several types of structural defects due to fatigue and wear caused by rolling stock passing over them. Most rail defects will develop gradually over time thus permitting inspection engineers to detect them in time before final failure occurs. In the UK, certain types of severe rail defects such as tache ovales, require the fitting of emergency clamps and the imposing of an Emergency Speed Restriction (ESR) until the defects are removed. Acoustic emission (AE) techniques can be applied for the detection and continuous monitoring of defect growth therefore removing the need of imposing strict ESRs. The work reported herewith aims to develop a sound methodology for the application of AE in order to detect and subsequently monitor damage evolution in rails. To validate the potential of the AE technique, tests have been carried out under laboratory conditions on three and four-point bending samples manufactured from 260 grade rail steel. Further tests, simulating the background noise conditions caused by passing rolling stock have been carried out using special experimental setups. The crack growth events have been simulated using a pencil tip break..

  12. Progress in Acoustic Transmission of Power through Walls

    Science.gov (United States)

    Sherrit,Stewart; Coty, Benjamin; Bao, Xiaoqi; Bar-Cohen, Yoseph; Badescu, Mircea; Chang, Zensheu

    2008-01-01

    A document presents updated information on implementation of the wireless acoustic-electric feed-through (WAEF) concept, which was reported in Using Piezoelectric Devices To Transmit Power Through Walls (NPO-41157), NASA Tech Briefs, Vol. 32, No. 6 (June 2008), page 70. To recapitulate: In a basic WAEF setup, a transmitting piezoelectric transducer on one side of a wall is driven at resonance to excite ultrasonic vibrations in the wall. A receiving piezoelectric transducer on the opposite side of the wall converts the vibrations back to an ultrasonic AC electric signal, which is then detected and otherwise processed in a manner that depends on the modulation (if any) applied to the signal and whether the signal is used to transmit power, data, or both. The present document expands upon the previous information concerning underlying physical principles, advantages, and potential applications of WAEF. It discusses the design and construction of breadboard prototype piezoelectric transducers for WAEF. It goes on to present results of computational simulations of performance and results of laboratory tests of the prototypes. In one notable test, a 100-W light bulb was lit by WAEF to demonstrate the feasibility of powering a realistic load.

  13. Acoustic elliptical cylindrical cloaks

    Institute of Scientific and Technical Information of China (English)

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

    2009-01-01

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

  14. Indoor acoustic gain design

    Science.gov (United States)

    Concha-Abarca, Justo Andres

    2002-11-01

    The design of sound reinforcement systems includes many variables and usually some of these variables are discussed. There are criteria to optimize the performance of the sound reinforcement systems under indoor conditions. The equivalent acoustic distance, the necessary acoustic gain, and the potential acoustic gain are parameters which must be adjusted with respect to the loudspeaker array, electric power and directionality of loudspeakers, the room acoustics conditions, the distance and distribution of the audience, and the type of the original sources. The design and installation of front of the house and monitoring systems have individual criteria. This article is about this criteria and it proposes general considerations for the indoor acoustic gain design.

  15. The Acoustical Properties of Indonesian Hardwood Species

    Directory of Open Access Journals (Sweden)

    Tarcisius Rio Mardikanto

    2012-08-01

    Full Text Available The acoustical properties of four Indonesian tropical hardwood species were evaluated in this study. The objectives of this study were to determine acoustical parameters e.g. logarithmic decrement, sound absorption, sound velocity as well as density and wood stiffness; and to evaluate the potential of those species for acoustical purposes. Sonokeling (Dalbergia latifolia, Mahoni (Swietenia mahagony, Acacia (Acacia mangium and Manii wood (Maesopsis eminii were selected in this research. Three different cutting plane patterns of sawn timber (quarter-sawn, flat-sawn, and plain-sawn were converted into small specimens. The methods for determining acoustical properties were longitudinal vibration testing and time of flight of ultrasonic wave method. The result showed no significant difference (α=0.05 of acoustical properties in logarithmic decrement, sound absorption, and ultrasonic velocity means on quarter-sawn, flat-sawn, and plain-sawn for all wood species tested. We found that Mahoni and Sonokeling had good acoustical properties of logarithmic decrement, ultrasonic wave velocity, and ratio of wood stiffness to wood density; and is preferred for crafting musical instruments. Acacia and Manii woods are recommended for developing acoustic panels in building construction because those species possess higher sound absorption values.

  16. Impact of the frequency of online verifications on the patient set-up accuracy and set-up margins

    Directory of Open Access Journals (Sweden)

    Mohamed Adel

    2011-08-01

    Full Text Available Abstract Purpose The purpose of the study was to evaluate the patient set-up error of different anatomical sites, to estimate the effect of different frequencies of online verifications on the patient set-up accuracy, and to calculate margins to accommodate for the patient set-up error (ICRU set-up margin, SM. Methods and materials Alignment data of 148 patients treated with inversed planned intensity modulated radiotherapy (IMRT or three-dimensional conformal radiotherapy (3D-CRT of the head and neck (n = 31, chest (n = 72, abdomen (n = 15, and pelvis (n = 30 were evaluated. The patient set-up accuracy was assessed using orthogonal megavoltage electronic portal images of 2328 fractions of 173 planning target volumes (PTV. In 25 patients, two PTVs were analyzed where the PTVs were located in different anatomical sites and treated in two different radiotherapy courses. The patient set-up error and the corresponding SM were retrospectively determined assuming no online verification, online verification once a week and online verification every other day. Results The SM could be effectively reduced with increasing frequency of online verifications. However, a significant frequency of relevant set-up errors remained even after online verification every other day. For example, residual set-up errors larger than 5 mm were observed on average in 18% to 27% of all fractions of patients treated in the chest, abdomen and pelvis, and in 10% of fractions of patients treated in the head and neck after online verification every other day. Conclusion In patients where high set-up accuracy is desired, daily online verification is highly recommended.

  17. 声波透射法在基桩检测中影响因素的深入分析%Analysis and Discussion About the Influencing Factors in the Pile Foundation Test by Acoustic Wave Transmission Method

    Institute of Scientific and Technical Information of China (English)

    赵守全; 赵常要; 朱兆荣

    2016-01-01

    This article is based on sound wave transmission method,analyzes the influence factors of pile foundation testing and points out the factors of the testing instrument,acoustic detecting tube material,temperature of testing environment, blocking pipe and tubes which are not parallel will affect the test results.Therefore,the influence degree of the influence factors on the test results and its mechanism are carried on analysis thoroughly,such as sound velocity anomaly problems caused by the acoustic detection tube is not parallel,although correction method is more,there are some limitations and shortcomings.The paper,adopts the correction method based on acoustic detecting tube space position relations,has achieved good correction effect,and consequently presents the corresponding processing methods or measures to reduce the influence degree of these factors on the test results,and finally the reliability of the testing results of sound wave transmis-sion method is improved.%本文就声波透射法在基桩检测中的影响因素这一问题进行了深入分析,指出了检测仪器、声测管材质、检测环境的温度、堵管、声测管不平行等因素都会对结果分析产生影响,并针对这些因素对检测结果的影响程度及机理进行了深入分析,如声测管不平行引起的声速异常问题,虽然修正方法较多,但都有一定的局限性和弊端,本文采用了基于声测管空间位置关系的修正方法取得了良好的修正效果,进一步给出了相应的处理方法或措施,使这些因素对检测结果的影响程度有效降低,提高了声波透射法检测结果的可信度。

  18. The COMPASS Setup for Physics with Hadron Beams

    CERN Document Server

    Abbon, Ph.; Akhunzyanov, R.; Alexandrov, Yu.; Alexeev, M.G.; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Austregesilo, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bicker, K.; Bielert, E.R.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bressan, A.; Buchele, M.; Burtin, E.; Capozza, L.; Ciliberti, P.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Cotte, D.; Crespo, M.L.; Curiel, Q.; Dafni, T.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Desforge, D.; Dinkelbach, A.M.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Durand, D.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Finger, M.; M. Finger jr; Fischer, H.; Franco, C.; von Hohenesche, N. du Fresne; Friedrich, J.M.; Frolov, V.; Gatignon, L.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giganon, A.; Gnesi, I.; Gobbo, B.; Goertz, S.; Gorzellik, M.; Grabmuller, S.; Grasso, A.; Gregori, M.; Grube, B.; Grussenmeyer, T.; Guskov, A.; Haas, F.; von Harrach, D.; Hahne, D.; Hashimoto, R.; Heinsius, F.H.; Herrmann, F.; Hinterberger, F.; Hoppner, Ch.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Jorg, P.; Joosten, R.; Kabuss, E.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kroumchtein, Z.V.; Kuchinski, N.; Kuhn, R.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Lednev, A.A.; Lehmann, A.; Levillain, M.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Menon, G.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Moinester, M.A.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Novy, J.; Nowak, W.D.; Nunes, Ana Sofia; Olshevsky, A.G.; Orlov, I.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pesaro, G.; Pesaro, V.; Peshekhonov, D.V.; Pires, C.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Reymond, J-M.; Rocco, E.; Rossiyskaya, N.S.; Rousse, J.Y.; Ryabchikov, D.I.; Rychter, A.; Samartsev, A.; Samoylenko, V.D.; Sandacz, A.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, K.; Schmieden, H.; Schonning, K.; Schopferer, S.; Schott, M.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Wolbeek, J. ter; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Tskhay, V.; Uhl, S.; Uman, I.; Virius, M.; Wang, L.; Weisrock, T.; Weitzel, Q.; Wilfert, M.; Windmolders, R.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zink, A.

    2015-01-01

    The main characteristics of the COMPASS experimental setup for physics with hadron beams are described. This setup was designed to perform exclusive measurements of processes with several charged and/or neutral particles in the final state. Making use of a large part of the apparatus that was previously built for spin structure studies with a muon beam, it also features a new target system as well as new or upgraded detectors. The hadron setup is able to operate at the high incident hadron flux available at CERN. It is characterised by large angular and momentum coverages, large and nearly flat acceptances, and good two and three-particle mass resolutions. In 2008 and 2009 it was successfully used with positive and negative hadron beams and with liquid hydrogen and solid nuclear targets. This article describes the new and upgraded detectors and auxiliary equipment, outlines the reconstruction procedures used, and summarises the general performance of the setup.

  19. IMPLEMENTATION OF INDUSTRIAL ROBOT-MANIPULATOR SETUPS IN EDUCATIONAL PROCESS

    Directory of Open Access Journals (Sweden)

    A. A. Bobtsov

    2013-01-01

    Full Text Available The article deals with the most important aspects of industrial robot-manipulator setups implementation as an educational tool for the workshop part of advanced technologies in robotics and control engineering courses.

  20. A new beam diagnostic system for the MASHA setup

    Science.gov (United States)

    Motycak, S.; Rodin, A. M.; Novoselov, A. S.; Podshibyakin, A. V.; Krupa, L.; Belozerov, A. V.; Vedeneyev, V. Yu.; Gulyaev, A. V.; Gulyaeva, A. V.; Kliman, J.; Salamatin, V. S.; Stepantsov, S. V.; Chernysheva, E. V.; Yuchimchuk, S. A.; Komarov, A. B.; Kamas, D.

    2016-09-01

    A new beam diagnostic system based on the PXI standard was developed, tested, and used in the MASHA setup experiment. The beam energy and beam current measurements were carried out using several methods. The online time-of-flight energy measurements were carried out using three pick-up detectors. We used two electronic systems to measure the time between the pick-ups. The first system was based on fast Agilent digitizers (2-channel, 4-GHz sampling rate), and the second one was based on a constant fraction discriminator (CFD) connected to a time-to-digital converter (TDC, 5-ps resolution). A new graphical interface to monitor the electronic devices and to perform the online calculations of energy was developed using MFC C++. The second system based on microchannel plate (time-of-flight) and silicon detectors for the determination of beam energy and the type of accelerated particles was also used. The beam current measurements were carried out with two different sensors. The first sensor is a rotating Faraday cup placed in front of the target, and the second one is an emission detector installed at the rear of the target. This system is now used in experiments for the synthesis of superheavy elements at the U400M cyclotron of the Flerov Laboratory of Nuclear Reactions (FLNR).

  1. Characterizing Acoustic Sources in Pressure Vessels

    Institute of Scientific and Technical Information of China (English)

    李路明; 郑鹏; 刘时风; 施克仁

    2002-01-01

    The "dream" of acoustic emission (AE) testing is to get the acoustic source characteristics from AE signals, especially when evaluating aging pressure vessels. In this paper, the wavelet transform was used to analyze different AE signals from cracks (surface and inner), pencil-lead-breakage and leakage. These acoustic sources were applied on an actual pressure vessel. While the vessel experienced hydraulic pressure, their AE signals were acquired by a digital AE testing system with a wide frequency band transducer and a high speed A/D converter. Then, the digital signals were analyzed using the wavelet transform method. Correlation coefficients of the transformed data show that the different acoustic sources can be easily identified.

  2. Calibration setup for ultralow-current transresistance amplifiers

    CERN Document Server

    Finardi, Ilaria

    2016-01-01

    We describe a calibration setup for the transresistance of low-current amplifiers, based on the capacitance-charging method. The calibration can be performed in the current range of typical interest for electron counting experiments. The setup implementation is simple and rugged, and is suitable to be embedded in larger experiments where the amplifier is employed. The calibration is traceable to units of capacitance and of time. The base relative accuracy of the implementation is in the 10^-5 range.

  3. Evaluating Speed Enforcement Field Set-Ups Used by Regional Police in Belgium: An Analysis of Speed Outcome Indicators

    Directory of Open Access Journals (Sweden)

    Brenda Wilmots

    2016-12-01

    Full Text Available In this paper the results from a field experiment (conducted in 2012 are presented, in which 3 regional police units in the Flemish region of Belgium each tested a particular combination of a speed control (with mobile radar in an anonymous car with communicative signage. The goal of this paper was to scientifically evaluate frequently used field set-ups. The following set-ups were tested in one week: (1 police unit 1: speed control with and without a static feedback sign placed after the control; (2 police unit 2: speed control with and without a digital feedback sign placed after the control; (3 police unit 3: speed display followed by a second speed display further along the road section. During certain time frames, speed control took place in between both signs. All tested field set-ups generated significant reductions in the speed level. Studying the effect of the different variations for each set-up reveals that the effect of the speed control is generally larger in combination with the signage alongside the road. After the period during which the police activities took place, speed levels again reached their initial level. Based on the before–after analysis, only in police area 2 was a small ‘time halo-effect’ found. To generalize results from this pilot study, repetition of tested set-ups in the field is recommended as well as testing on a larger scale.

  4. A Full-size High Temperature Superconducting Coil Employed in a Wind Turbine Generator Set-up

    DEFF Research Database (Denmark)

    Song, Xiaowei (Andy); Mijatovic, Nenad; Kellers, Jürgen

    2016-01-01

    is tested in LN2 first, and then tested in the set-up so that the magnetic environment in a real generator is reflected. The experimental results are reported, followed by a finite element simulation and a discussion on the deviation of the results. The tested and estimated Ic in LN2 are 148 A and 143 A......A full-size stationary experimental set-up, which is a pole pair segment of a 2 MW high temperature superconducting (HTS) wind turbine generator, has been built and tested under the HTS-GEN project in Denmark. The performance of the HTS coil is crucial to the set-up, and further to the development...

  5. World Conference on Acoustic Emission 2013

    CERN Document Server

    Wu, Zhanwen; Zhang, Junjiao

    2015-01-01

    This volume collects the papers from the 2013 World Conference on Acoustic Emission in Shanghai. The latest research and applications of Acoustic Emission (AE) are explored, with particular emphasis on detecting and processing of AE signals, development of AE instrument and testing standards, AE of materials, engineering structures and systems, including the processing of collected data and analytical techniques as well as experimental case studies.

  6. EPECUR setup for the search of narrow baryon resonances in the pion-proton scattering

    CERN Document Server

    Andreev, V A; Golubev, V V; Gridnev, A B; Kovalev, A I; Kozlenko, N G; Kozlov, V S; Krivshich, A G; Novinsky, D V; Sadler, M E; Sumachev, V V; Tarakanov, V I; Trautman, V Yu

    2013-01-01

    EPECUR experimental setup is aimed at the search of narrow resonant states by precision measurement of differential and total reaction cross sections of pion-nucleon interaction with 1 MeV pion energy steps. In five years passed from the idea of the experiment till the start of the data taking in April of 2009, a new apparatus was build from scratch at the universal beam line 322 of ITEP proton synchrotron U-10. The setup is essentially a non-magnetic spectrometer with a liquid hydrogen target based on the large aperture drift chambers with hexagonal structure. The unique properties of the beam line allow individual pion momentum measurement with the accuracy better than 0.1%. The momentum tagging is done with 1 mm pitch proportional chambers located in the first focus of the beam line. The design of numerous subsystems of the setup is based on modern electronic components including microprocessors and FPGA. All the subsystems are tuned and tested both individually and as parts of the whole working setup. The...

  7. New radio-frequency setup for studying large 2D complex plasma crystals

    Science.gov (United States)

    Nosenko, Vladimir; Meyer, John; Thomas, Hubertus

    2016-09-01

    There is a growing body of evidence that many properties of complex plasmas, such as thermal conductivity and diffusion coefficient may be system-size dependent. To test this assumption, experiments are needed where the size of a complex plasma can be varied in a wide range. So far, the existing experimental setups (based on various modifications of the GEC rf reference cell) allowed the maximum size of a good-quality 2D plasma crystal of about 6-7 cm. To obtain a much larger uniform 2D plasma crystal, a larger setup is necessary. In this presentation, we report on the new radio-frequency setup that has been built and is now operational in the Research Group on Complex Plasmas. It is based on a relatively large (90 cm in diameter) vacuum chamber where a radio-frequency discharge is used to levitate dust particles. The discharge is created between the lower rf electrode and the grounded chamber walls, the particles levitate in the plasma (pre)sheath above the electrode and are observed through the large top glass window and through the side windows. The first observations of plasma crystals in the new setup will be reported.

  8. Investigation of the energy dependence of breakdown properties with a DC spark setup

    CERN Document Server

    Hansen, Anita; Calatroni, S

    2009-01-01

    The Compact LInear Collider (CLIC) study is a site independent feasibility study aiming at the development of a realistic technology at an affordable cost for a future linear electron-positron collider. The European Organization for Nuclear Research (CERN) is one of the collaborators for the CLIC study.The CLIC Test Facility (CTF3) positioned at CERN provides testing of this technology, including the testing of the proposed radio-frequency (RF) structures in a two-beam concept to produce the necessary accelerating electric field as high as 100 MV/m to reach the goal of a nominal total energy of 3 TeV. One problem at such high accelerating fields is electrical discharges, i.e. sparks, damaging the inside of the RF structures as well as deflecting the trajectories of accelerated particles. A Direct Current (DC) spark test setup is in use at CERN to aid the understanding of electrical discharges under vacuum conditions, also called vacuum arcs. In contrast to the more complex CTF3 setup, the DC spark setup is si...

  9. Acoustic Feature-based Pronunciation Test on International Students of Chinese Affricates%基于声学特征的留学生汉语塞擦音测试探索

    Institute of Scientific and Technical Information of China (English)

    李银玲

    2012-01-01

    文从声学语音学的角度出发,提出将声学语音学中辅音的声学特征应用到非母语汉语塞擦音测试中来。利用Praat语音分析软件,提取留学生汉语塞擦音噪音起始时间(VOT)、送气时长、送气时长与韵母时长的比值三个参量,并和标准音进行对比,结合主观评分方法,试图量化CAP三级评判标准假设,探讨一种客观语音评分方法,同时诊断出留学生汉语塞擦音语音偏误,并对对外汉语语音教学提出建议。%Starting from the perspective of acoustic phonetics This thesis proposes a diagnosing pronunciation test of Chinese affricates based on the acoustic features of consonants. By using Praat, three major acoustic parameters, voice onset time (VOT), aspiration duration (AD), and the ratio of AD to vowel duration (VD) are extracted and compared with the standard pronunciation. Combined with CAP--the hypothesized three-level rating scale, this study will also attempt to quantify CAP and further diagnose the pronunciation errors of non-native Chinese learners and relative pronunciation teaching suggestions are proposed.

  10. Uncertainty analysis in acoustic investigations

    OpenAIRE

    2013-01-01

    The problem of uncertainty assessment in acoustic investigations is presented in the hereby paper. The aspect of the uncertainty asymmetry in processing of data obtained in the measuring test of sound levels, determined in decibels, was sketched. On the basis of the analysis of data obtained in the continuous monitoring of road traffic noise in Krakow typical probability distributions for a day, evening and night were determined. The method of the uncertainty assessment based on the propagati...

  11. 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...

  12. 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...

  13. Deep Water Ocean Acoustics

    Science.gov (United States)

    2016-04-30

    OASIS, INC. 1 Report No. QSR-14C0172-Ocean Acoustics-043016 Quarterly Progress Report Technical and Financial Deep Water Ocean Acoustics...understanding of the impact of the ocean and seafloor environmental variability on deep- water (long-range) ocean acoustic propagation and to...improve our understanding. During the past few years, the physics effects studied have been three-dimensional propagation on global scales, deep water

  14. Nearfield Acoustical Holography

    Science.gov (United States)

    Hayek, Sabih I.

    Nearfield acoustical holography (NAH) is a method by which a set of acoustic pressure measurements at points located on a specific surface (called a hologram) can be used to image sources on vibrating surfaces on the acoustic field in three-dimensional space. NAH data are processed to take advantage of the evanescent wavefield to image sources that are separated less that one-eighth of a wavelength.

  15. A rail system for circular synthetic aperture sonar imaging and acoustic target strength measurements: design/operation/preliminary results.

    Science.gov (United States)

    Kennedy, J L; Marston, T M; Lee, K; Lopes, J L; Lim, R

    2014-01-01

    A 22 m diameter circular rail, outfitted with a mobile sonar tower trolley, was designed, fabricated, instrumented with underwater acoustic transducers, and assembled on a 1.5 m thick sand layer at the bottom of a large freshwater pool to carry out sonar design and target scattering response studies. The mobile sonar tower translates along the rail via a drive motor controlled by customized LabVIEW software. The rail system is modular and assembly consists of separately deploying eight circular arc sections, measuring a nominal center radius of 11 m and 8.64 m arc length each, and having divers connect them together in the underwater environment. The system enables full scale measurements on targets of interest with 0.1° angular resolution over a complete 360° aperture, without disrupting target setup, and affording a level of control over target environment conditions and noise sources unachievable in standard field measurements. In recent use, the mobile cart carrying an instrumented sonar tower was translated along the rail in 720 equal position increments and acoustic backscatter data were acquired at each position. In addition, this system can accommodate both broadband monostatic and bistatic scattering measurements on targets of interest, allowing capture of target signature phenomena under diverse configurations to address current scientific and technical issues encountered in mine countermeasure and unexploded ordnance applications. In the work discussed here, the circular rail apparatus is used for acoustic backscatter testing, but this system also has the capacity to facilitate the acquisition of magnetic and optical sensor data from targets of interest. A brief description of the system design and operation will be presented along with preliminary processed results for data acquired from acoustic measurements conducted at the Naval Surface Warfare Center, Panama City Division Test Pond Facility. [Work Supported by the U.S. Office of Naval Research and

  16. 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...

  17. 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.

  18. 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...

  19. Localized acoustic surface modes

    Science.gov (United States)

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

    2016-04-01

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

  20. 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...

  1. 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.

  2. 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...

  3. Minimization of number of setups for mounting machines

    Energy Technology Data Exchange (ETDEWEB)

    Kolman, Pavel; Nchor, Dennis; Hampel, David [Department of Statistics and Operation Analysis, Faculty of Business and Economics, Mendel University in Brno, Zemědělská 1, 603 00 Brno (Czech Republic); Žák, Jaroslav [Institute of Technology and Business, Okružní 517/10, 370 01 České Budejovice (Czech Republic)

    2015-03-10

    The article deals with the problem of minimizing the number of setups for mounting SMT machines. SMT is a device used to assemble components on printed circuit boards (PCB) during the manufacturing of electronics. Each type of PCB has a different set of components, which are obligatory. Components are placed in the SMT tray. The problem consists in the fact that the total number of components used for all products is greater than the size of the tray. Therefore, every change of manufactured product requires a complete change of components in the tray (i.e., a setup change). Currently, the number of setups corresponds to the number of printed circuit board type. Any production change affects the change of setup and stops production on one shift. Many components occur in more products therefore the question arose as to how to deploy the products into groups so as to minimize the number of setups. This would result in a huge increase in efficiency of production.

  4. Acoustic measuring techniques for suspended sediment

    Science.gov (United States)

    Gruber, P.; Felix, D.; Storti, G.; Lattuada, M.; Fleckenstein, P.; Deschwanden, F.

    2016-11-01

    Acoustic signals can be used in various ways for suspended sediment monitoring. One possibility which lends itself particularly well in the context of hydropower plants (HPPs), is to use installations for acoustic discharge measurement (ADM). Such installations already exist at waterways of many HPPs. Similar to certain turbidimeters, the attenuation of the forward scattered signal travelling through the water-sediment mixture is correlated with suspended sediment concentration (SSC). This correlation can be based on reference SSCs, e.g. from gravimetric analyses of bottle samples. Without the need of additional sensors and practically maintenance-free, this method is used successfully in the HPP Fieschertal to warn the HPP operator of high SSC to prevent excessive turbine abrasion. Acoustic methods and systems that allow for estimating both SSC and particle size distribution (PSD) are under development. The simultaneous determination of SSC and PSD is not possible using a single frequency. Therefore, multi-frequency approaches are investigated for generally scattered signals. When backscattered signals are used, a stronger frequency dependency can be exploited. However, the reliable simultaneous determination of particle size (and distribution) and concentration is still a major challenge due to a low signal-to-noise ratio and an ill- posed problem of estimating concentration and size from recorded signals. The optimal setup configuration (angles, frequencies) for such a system is not unique and further investigations are recommended.

  5. Basin Acoustic Seamount Scattering Experiment (BASSEX) Data Analysis and Modeling

    Science.gov (United States)

    2016-06-07

    Kauai source at various ranges and bearings. OBJECTIVES The primary objective of this work is to measure aspects of acoustic propagation that...range-dependent environments. The primary goal is to understand the physics of the acoustic propagation in complex environments. Three specific...During the test acoustic transmissions from sources used in the SPICEX and LOAPEX experiments (PI: Dr. Peter Worcester, SIO and Dr. Jim Mercer, APL-UW

  6. Vibration and acoustic environments for payload/cargo integration

    Science.gov (United States)

    Hill, R. E.; Coody, M. C.

    1983-01-01

    Shuttle orbiter launch vibration and acoustic environments for cargo bay/payload interfaces are predicted. Data acquired during Shuttle flight tests are compared with the preflight estimates. Vibration response data for payload attachment locations are presented, along with acoustic data in the form of noise-level spectra measured at various locations in the cargo bay and space averages of the noise levels. It is shown that the payload-bay vibration and acoustic environments are generally less severe than predicted.

  7. Estimation of functional preparedness of young handballers in setup time

    Directory of Open Access Journals (Sweden)

    Favoritоv V.N.

    2012-11-01

    Full Text Available The dynamics of level of functional preparedness of young handballers in setup time is shown. It was foreseen to make alteration in educational-training process with the purpose of optimization of their functional preparedness. 11 youths were plugged in research, calendar age 14 - 15 years. For determination of level of their functional preparedness the computer program "SVSM" was applied. It is set that at the beginning of setup time of 18,18% of all respondent functional preparedness is characterized by a "middle" level, 27,27% - below the "average", 54,54% - "above" the average. At the end of setup time among sportsmen representatives prevailed with the level of functional preparedness "above" average - 63,63%, with level "high" - 27,27%, sportsmen with level below the average were not observed. Efficiency of the offered system of trainings employments for optimization of functional preparedness of young handballers is well-proven.

  8. Objected constrained registration and manifold learning: A new patient setup approach in image guided radiation therapy of thoracic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chen Ting; Jabbour, Salma K.; Haffty, Bruce G.; Yue, Ning [Radiation Oncology Department, Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, New Jersey 08901 (United States); Qin Songbing [Department of Radiation Oncology, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China)

    2013-04-15

    Purpose: The management of thoracic malignancies with radiation therapy is complicated by continuous target motion. In this study, a real time motion analysis approach is proposed to improve the accuracy of patient setup. Methods: For 11 lung cancer patients a long training fluoroscopy was acquired before the first treatment, and multiple short testing fluoroscopies were acquired weekly at the pretreatment patient setup of image guided radiotherapy (IGRT). The data analysis consisted of three steps: first a 4D target motion model was constructed from 4DCT and projected to the training fluoroscopy through deformable registration. Then the manifold learning method was used to construct a 2D subspace based on the target motion (kinetic) and location (static) information in the training fluoroscopy. Thereafter the respiratory phase in the testing fluoroscopy was determined by finding its location in the subspace. Finally, the phase determined testing fluoroscopy was registered to the corresponding 4DCT to derive the pretreatment patient position adjustment for the IGRT. The method was tested on clinical image sets and numerical phantoms. Results: The registration successfully reconstructed the 4D motion model with over 98% volume similarity in 4DCT, and over 95% area similarity in the training fluoroscopy. The machine learning method derived the phase values in over 98% and 93% test images of the phantom and patient images, respectively, with less than 3% phase error. The setup approach achieved an average accumulated setup error less than 1.7 mm in the cranial-caudal direction and less than 1 mm in the transverse plane. All results were validated against the ground truth of manual delineations by an experienced radiation oncologist. The expected total time for the pretreatment setup analysis was less than 10 s. Conclusions: By combining the registration and machine learning, the proposed approach has the potential to improve the accuracy of pretreatment setup for

  9. Why IV Setup for Stream Ciphers is Difficult

    DEFF Research Database (Denmark)

    Zenner, Erik

    2007-01-01

    In recent years, the initialization vector (IV) setup has proven to be the most vulnerable point when designing secure stream ciphers. In this paper, we take a look at possible reasons why this is the case, identifying numerous open research problems in cryptography.......In recent years, the initialization vector (IV) setup has proven to be the most vulnerable point when designing secure stream ciphers. In this paper, we take a look at possible reasons why this is the case, identifying numerous open research problems in cryptography....

  10. Shape Setup System for 1700 Hot Strip Mill

    Institute of Scientific and Technical Information of China (English)

    GUO Zhong-feng; XU Jian-zhong; LI Chang-sheng; LIU Xiang-hua

    2007-01-01

    Shape setup (SSU) system is the core technology for hot strip mill (HSM). A precise SSU system was used to improve the strip quality for HSM. The function of SSU, setup, and feedback was introduced. The main mathematical models of roll gap profile and longitudinal strain difference are set up. Strip profile allocation strategy was researched according to the SSU system of a domestic 1 700 mm HSM. The SSU system was put into practical use and the measurement results showed that strip flatness variation and strip profile variation could be controlled in target scope.

  11. Acoustic fluidization for earthquakes?

    OpenAIRE

    Sornette, D.; Sornette, A.

    2000-01-01

    Melosh [1996] has suggested that acoustic fluidization could provide an alternative to theories that are invoked as explanations for why some crustal faults appear to be weak. We show that there is a subtle but profound inconsistency in the theory that unfortunately invalidates the results. We propose possible remedies but must acknowledge that the relevance of acoustic fluidization remains an open question.

  12. ESTERR-PRO: A Setup Verification Software System Using Electronic Portal Imaging

    Directory of Open Access Journals (Sweden)

    Pantelis A. Asvestas

    2007-01-01

    Full Text Available The purpose of the paper is to present and evaluate the performance of a new software-based registration system for patient setup verification, during radiotherapy, using electronic portal images. The estimation of setup errors, using the proposed system, can be accomplished by means of two alternate registration methods. (a The portal image of the current fraction of the treatment is registered directly with the reference image (digitally reconstructed radiograph (DRR or simulator image using a modified manual technique. (b The portal image of the current fraction of the treatment is registered with the portal image of the first fraction of the treatment (reference portal image by applying a nearly automated technique based on self-organizing maps, whereas the reference portal has already been registered with a DRR or a simulator image. The proposed system was tested on phantom data and on data from six patients. The root mean square error (RMSE of the setup estimates was 0.8±0.3 (mean value ± standard deviation for the phantom data and 0.3±0.3 for the patient data, respectively, by applying the two methodologies. Furthermore, statistical analysis by means of the Wilcoxon nonparametric signed test showed that the results that were obtained by the two methods did not differ significantly (P value >0.05.

  13. Real-time setup to record radon emission during rock deformation: implications for geochemical surveillance

    Science.gov (United States)

    Tuccimei, P.; Mollo, S.; Soligo, M.; Scarlato, P.; Castelluccio, M.

    2015-02-01

    Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analyzing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress-strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A re-circulating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collision of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into an uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows to obtain a variety of stress-strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  14. Real-time setup to measure radon emission during rock deformation: implications for geochemical surveillance

    Science.gov (United States)

    Tuccimei, P.; Mollo, S.; Soligo, M.; Scarlato, P.; Castelluccio, M.

    2015-05-01

    Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analysing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress-strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A recirculating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collisions of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into a uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows obtaining a variety of stress-strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  15. Real-time setup to record radon emission during rock deformation: implications for geochemical surveillance

    Directory of Open Access Journals (Sweden)

    P. Tuccimei

    2015-02-01

    Full Text Available Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analyzing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress–strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A re-circulating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collision of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into an uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows to obtain a variety of stress–strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  16. Automation of a high-speed imaging setup for differential viscosity measurements

    Science.gov (United States)

    Hurth, C.; Duane, B.; Whitfield, D.; Smith, S.; Nordquist, A.; Zenhausern, F.

    2013-12-01

    We present the automation of a setup previously used to assess the viscosity of pleural effusion samples and discriminate between transudates and exudates, an important first step in clinical diagnostics. The presented automation includes the design, testing, and characterization of a vacuum-actuated loading station that handles the 2 mm glass spheres used as sensors, as well as the engineering of electronic Printed Circuit Board (PCB) incorporating a microcontroller and their synchronization with a commercial high-speed camera operating at 10 000 fps. The hereby work therefore focuses on the instrumentation-related automation efforts as the general method and clinical application have been reported earlier [Hurth et al., J. Appl. Phys. 110, 034701 (2011)]. In addition, we validate the performance of the automated setup with the calibration for viscosity measurements using water/glycerol standard solutions and the determination of the viscosity of an "unknown" solution of hydroxyethyl cellulose.

  17. Experimental setup for Single Event Effects at the São Paulo 8UD Pelletron Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, V.A.P. [Instituto de Física da Universidade de São Paulo, São Paulo, SP (Brazil); Added, N., E-mail: nemitala@if.usp.br [Instituto de Física da Universidade de São Paulo, São Paulo, SP (Brazil); Medina, N.H.; Macchione, E.L.A.; Tabacniks, M.H.; Aguirre, F.R. [Instituto de Física da Universidade de São Paulo, São Paulo, SP (Brazil); Silveira, M.A.G.; Santos, R.B.B. [Centro Universitário da FEI, São Bernardo do Campo, SP (Brazil); Seixas, L.E. [Centro de Tecnologia da Informação Renato Archer, Campinas, SP (Brazil)

    2014-08-01

    In this work we present an experimental setup mounted in one of the beam lines at the São Paulo 8UD Pelletron Accelerator in order to study Single Event Effects in electronic devices. The basic idea is to use elastic scattering collisions to achieve a low-flux with a high-uniformity ion beam to irradiate several devices. {sup 12}C, {sup 16}O, {sup 28}Si, {sup 35}Cl and {sup 63}Cu beams were used to test the experimental setup. In this system it is possible to use efficiently LET values of 17 MeV/mg/cm{sup 2} for an external beam arrangement and up to 32 MeV/mg/cm{sup 2} for in-vacuum irradiation.

  18. Automation of a high-speed imaging setup for differential viscosity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hurth, C.; Duane, B.; Whitfield, D.; Smith, S.; Nordquist, A.; Zenhausern, F. [Center for Applied Nanobioscience and Medicine, The University of Arizona College of Medicine, 425 N 5th Street, Phoenix, Arizona 85004 (United States)

    2013-12-28

    We present the automation of a setup previously used to assess the viscosity of pleural effusion samples and discriminate between transudates and exudates, an important first step in clinical diagnostics. The presented automation includes the design, testing, and characterization of a vacuum-actuated loading station that handles the 2 mm glass spheres used as sensors, as well as the engineering of electronic Printed Circuit Board (PCB) incorporating a microcontroller and their synchronization with a commercial high-speed camera operating at 10 000 fps. The hereby work therefore focuses on the instrumentation-related automation efforts as the general method and clinical application have been reported earlier [Hurth et al., J. Appl. Phys. 110, 034701 (2011)]. In addition, we validate the performance of the automated setup with the calibration for viscosity measurements using water/glycerol standard solutions and the determination of the viscosity of an “unknown” solution of hydroxyethyl cellulose.

  19. Acoustic ground impedance meter

    Science.gov (United States)

    Zuckerwar, A. J. (Inventor)

    1984-01-01

    A method and apparatus are presented for measuring the acoustic impedance of a surface in which the surface is used to enclose one end of the chamber of a Helmholz resonator. Acoustic waves are generated in the neck of the resonator by a piston driven by a variable speed motor through a cam assembly. The acoustic waves are measured in the chamber and the frequency of the generated acoustic waves is measured by an optical device. These measurements are used to compute the compliance and conductance of the chamber and surface combined. The same procedure is followed with a calibration plate having infinite acoustic impedance enclosing the chamber of the resonator to compute the compliance and conductance of the chamber alone. Then by subtracting, the compliance and conductance for the surface is obtained.

  20. Cochlear bionic acoustic metamaterials

    Science.gov (United States)

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

    2014-11-01

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

  1. 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...

  2. Ocean acoustic reverberation tomography.

    Science.gov (United States)

    Dunn, Robert A

    2015-12-01

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

  3. Nonlinear acoustics of water-saturated marine sediments

    DEFF Research Database (Denmark)

    Jensen, Leif Bjørnø

    1976-01-01

    Interest in the acoustic qualities of water-saturated marine sediments has increased considerably during recent years. The use of sources of high-intensity sound in oil propsecting, in geophysical and geological studies of bottom and subbottom materials and profiles and recently in marine...... archaeology has emphasized the need of information about the nonlinear acoustic qualities of water-saturated marine sediments. While the acoustic experiments and theoretical investigations hitherto performed have concentrated on a determination of the linear acoustic qualities of water-saturated marine...... sediments, their parameters of nonlinear acoustics are still unexplored. The strong absorption, increasing about linearly with frequency, found in most marine sediments and the occurrence of velocity dispersion by some marine sediments restrict the number of nonlinear acoustic test methods traditionally...

  4. A NOVEL ELLIPSOIDAL ACOUSTIC INFINITE ELEMENT

    Institute of Scientific and Technical Information of China (English)

    YANG Rui-liang; WANG Hong-zhen

    2005-01-01

    A novel ellipsoidal acoustic infinite element is proposed. It is based a new pressure representation, which can describe and solve the ellipsoidal acoustic field more exactly. The shape functions of this novel acoustic infinite element are similar .to the Burnett's method, while the weight functions are defined as the product of the complex conjugates of the shaped functions and an additional weighting factor. The code of this method is cheap to generate as for 1-D element because only 1-D integral needs to be numerical. Coupling with the standard finite element, this method provides a capability for very efficiently modeling acoustic fields surrounding structures of virtually any practical shape. This novel method was deduced in brief and the conclusion was kept in detail. To test the feasibility of this novel method efficiently, in the examples the infinite elements were considered, excluding the finite elements relative. This novel ellipsoidal acoustic infinite element can deduce the analytic solution of an oscillating sphere. The example of a prolate spheroid shows that the novel infinite element is superior to the boundary element and other acoustic infinite elements. Analytical and numerical results of these examples show that this novel method is feasible.

  5. A Magnetic Set-Up to Help Teach Newton's Laws

    Science.gov (United States)

    Panijpan, Bhinyo; Sujarittham, Thanida; Arayathanitkul, Kwan; Tanamatayarat, Jintawat; Nopparatjamjomras, Suchai

    2009-01-01

    A set-up comprising a magnetic disc, a solenoid and a mechanical balance was used to teach first-year physics students Newton's third law with the help of a free body diagram. The image of a floating magnet immobilized by the solenoid's repulsive force should help dispel a common misconception of students as regards the first law: that stationary…

  6. Easy ways to offload diabetic foot ulcer in rural setup

    OpenAIRE

    Agrawal, Vijay P

    2014-01-01

    Diabetic wound management has become a foremost problem in recent era. Offloading is one of the cornerstones of gold-standard treatment in diabetic neuropathic foot ulcer. The following article reviews the easily made offloading systems which are ideal to use in rural setup to offload diabetic foot ulcer.

  7. Modelling perceptual characteristics of loudspeaker reproduction in a stereo setup

    DEFF Research Database (Denmark)

    Volk, Christer Peter; Bech, Søren; Pedersen, Torben Holm

    2017-01-01

    of the perceptual evaluation, four of the descriptors were found suited for modelling, with the purpose of developing metrics for prediction of Bass depth, Punch, Brilliance, and Dark-Bright. Bass depth and Punch were modelled as one due to high correlation between them. The experimental setup included loudspeaker...

  8. The setup of a mobile mobility panel for the Netherlands

    NARCIS (Netherlands)

    Geurs, K.T.; Veenstra, S.A.; Thomas, T.

    2013-01-01

    This paper describes the setup of the Dutch Mobile Mobility Panel project, in which GPS-enabled mobile phones (smartphones) are used as a passive multiple-week and multiple-year travel behaviour data collection tool. The data collection methodology used in the Dutch Mobile Mobility Panel comprised f

  9. View of the WA10 set-up

    CERN Multimedia

    1977-01-01

    The WA10 experiment by the Geneva-Lausanne Collaboration was set-up in the H5 beam (unseparated, up to 50 GeV/c) to study K+-p --> K0pi+-p and other reactions of similar topology, and the energy dependence of resonance production.

  10. Flat acoustic lens by acoustic grating with curled slits

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-10-03

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

  11. THE INFLUENCE OF WAVE PATTERNS AND FREQUENCY ON THERMO-ACOUSTIC COOLING EFFECT

    Directory of Open Access Journals (Sweden)

    CHEN BAIMAN

    2011-06-01

    Full Text Available With the increasing environmental challenges, the search for an environmentally benign cooling technology that has simple and robust architecture continues. Thermo-acoustic refrigeration seems to be a promising candidate to fulfil these requirements. In this study, a simple thermo-acoustic refrigeration system was fabricated and tested. The thermo-acoustic refrigerator consists of acoustic driver (loudspeaker, resonator, stack, vacuum system and testing system. The effect of wave patterns and frequency on thermo-acoustic cooling effect was studied. It was found that a square wave pattern would yield superior cooling effects compared to other wave patterns tested.

  12. Evaluation of microscopic deformation behaviors of metal matrix composite by means of SFC test and acoustic emission (Part I :Effect of loading direction)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon Hyun; Kang, Moon Phil [Pusan National University, Pusan (Korea, Republic of)

    1998-11-15

    Metal matrix composites(MMCs) offer significant increase in elastic modulus and strength as well as improve resistance to fatigue initiation, creep and wear. For the successful application of MMC to structure, it is very important to understand micro-failure mechanism of material. However, due to complex deformation behavior intrinsically of bulk composite panel, single fiber composite(SFC) has been successfully used to understand a fundamental mechanism of deformation in MMC. The substantial failure mechanisms of MMC were affected by many factors such as the loading direction, the heat treatment condition, matrix properties and volume fraction. In this study, the microscopic deformation behavior of MMC is investigated for single SiC fiber reinforced aluminium alloy under the different loading direction, that is, longitudinal and transverse loading. Acoustic emission(AE) technique has been also used to detect the signals corresponding to each microscopic deformation behavior under the loading. Special attention is given to AE characteristics associated with interfacial debonding between fiber and matrix under the different leading direction.

  13. The convergence fluctuation of light by clusters of galaxies - a cosmological test using the second acoustic peak of the microwave background

    CERN Document Server

    Lieu, R

    2004-01-01

    The weak lensing magnification of distant light by clusters of galaxies, assumed to be virialized systems with an NFW density profile, was calculated analytically as a statistical average over a random non-evolving distribution within $z=1$. The effect is exactly cancelled by the Dyer-Roeder beam in between clusters - this conclusion is valid also for an ensemble of spherical clumps of arbitrary density profile. An analytical expression for the variance in the mean magnification is provided, using the general formula from our previous work. The all sky fluctuation in the angular size of the microwave background second acoustic peak, due to the random placement of cluster lenses in the intervening space, is then derived to be $\\approx$ 33 %. Moreover, this standard deviation corresponds to that of a highly skewed magnification distribution, with a long tail extending towards the side of positive magnification, since any negative excursion from the mean cannot cross the hard limit imposed by the Dyer-Roeder emp...

  14. Acoustically-Controlled Oil Well Pressure Switch Development and Testing%油井声控压差平衡式开关控制器的研制与试验

    Institute of Scientific and Technical Information of China (English)

    陈江烨; 王一良; 侯庆春; 杨松

    2015-01-01

    为了克服传统油井找水工艺中施工复杂、生产周期长、费用高、准确性低等缺点,提高油井找水效率和准确性,研制了油井找堵水声控压差平衡式开关控制器。该开关控制器采用自适应动态压力平衡系统,其活塞阀开启和关闭时可承受20 M Pa压力差;采用油管传输声波信号的声波遥控技术,从地面遥控井下开关控制器开启、关闭,根据工艺要求进行分层开采或分段开采。室内静压试验表明,开关控制器在125℃、50 M Pa高温高压条件下,稳压30 min ,整体设备无渗漏无变形;耐压差试验表明,活塞在承受25 M Pa压差的情况下,压力平衡装置可以承受压差,电机驱动活塞做上下往复运动,动密封不渗不漏。现场试验表明,声波接收器接收地面指令后,可以控制电机驱动装置打开或关闭开关阀。试验结果表明,该开关控制器可为油井提高开采效率提供技术支持。%Conventional techniques for detecting in oil wells have been disadvantageous due to their complex process ,long production period ,high cost and low accuracy .In order to enhance the efficiency and accuracy of the techniques used for water detection and plugging ,an acoustic controlled pressure-bal-ance switch has been developed .With an adaptive dynamic pressure balance system ,piston valves in the switch can endure differential pressure up to 20 MPa during opening and closing processes .By means of re-mote acoustic controlled technique that transmits acoustic signals through tubing ,the down-hole switch can be controlled remotely on the ground to facilitate production in different layers (in vertical wells) or in different intervals (in horizontal wells) according to operational requirements .Laboratory static pressure testing shows that the switch can withstand high temperature up to 125 ℃ and high pressure up to 50 MPa for 30 min with no leak or deformation .Differential

  15. Auditory tests in 14 patients(16 ears)with acoustic neuroma%听神经瘤致聋机理——14例(16耳)听神经瘤病人听力测试结果分析

    Institute of Scientific and Technical Information of China (English)

    徐进; 刘钅延; 陈秀伍; 廉能静; 刘博

    2001-01-01

    Objective:To investigate the relationship between hearing loss and acoustic neuroma(AN),the tests of pure tone audiometry,acoustic emissions impedance audiometry,audiometry brainstem response(ABR)and evoked otoacoustic emissions(EOAE)wee measured in 14 patients (16 ears)from March 1999 to December 2000.Methods:Fourteen patients (16 ears)with acoustic neuroma (8 males and 6 females,ranging in age from 21 to 72 years old)were diagnosed by CT or MRI scaning,and final confirmed by surgery and pathology.In the auditory tests ,efferent suppression test was curried out only in 4 ears with recordable emissions,promontory stimulation test (PST)was examined only in 5 ears with severe or profound deafness (hearing loss≥80dB SPL)who have no both measurable ABR and recordable EOAE.Results:It was found that 2 ears (12.5%,2/16)of the AN ears showed neural impairment,6 ears (37.5%,6/16)were cochlear impairment and 8 ears (50.0%,8/16)were cochlear-retrocochlear impairment.All of 4 tumors ears with EOAE emission have a disorders of efferent function.Conclusion:EOAE test had significant value for evaluation of the status of cochlear function (at the level of outer hair cells)in AN patients.The retrocochlear auditory nerve function of AN patients were evaluated by the tests of ABR combined PST which showed significant value.Results showed that the hearing impairment of AN have different levels of the peripheral auditory system according to auditory tests,including cochlear,eighth cranial nerve and efferent nerve level at the same or independently.%目的:探讨听神经瘤听力损失的病理生理机制。方法:对14例(16耳)听神经瘤患者行纯音听阈、阻抗、听性脑干反应(ABR)、诱发耳声发射测试(EOAE)及CT和(或)MRI扫描。EOAE能引出的4耳还检测其传出抑制功能,ABR不能检测且EOAE不能引出的重度聋(听力损失大于80dB)有5耳行鼓岬刺激试验(PST)。结果:16耳听神经瘤中2耳(12.50%)听力

  16. Predicting Acoustics in Class Rooms

    DEFF Research Database (Denmark)

    Christensen, Claus Lynge; Rindel, Jens Holger

    2005-01-01

    Typical class rooms have fairly simple geometries, even so room acoustics in this type of room is difficult to predict using today's room acoustic computer modeling software. The reasons why acoustics of class rooms are harder to predict than acoustics of complicated concert halls might...

  17. Underwater Applications of Acoustical Holography

    Directory of Open Access Journals (Sweden)

    P. C. Mehta

    1984-01-01

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

  18. Cryo-vacuum testing of the JWST Integrated Science Instrument Module (SPIE)

    Science.gov (United States)

    Kimble, Randy A.; Vila, M. Begona; Van Campen, Julie; Birkmann, Stephan M.; Comber, Brian J.; Fatig, Curtis C.; Glasse, Alistair C. H.; Glazer, Stuart D.; Kelly, Douglas M.; Mann, Steven D.; Martel, Andre R.; Novo-Gradac, Kevin J.; Ohl, Raymond G.; Penanen, Konstantin; Rohrbach, Scott O.; Sullivan, Joseph F.; Zak, Dean; Zhou, Julia

    2016-01-01

    In late 2015/early 2016, a major cryo-vacuum test was carried out for the Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope (JWST). This test comprised the final cryo-certification and calibration test of the ISIM, after its ambient environmental test program (vibration, acoustics, EMI/EMC), and before its delivery for integration with the rest of the JWST observatory. Over the 108-day period of the round-the-clock test program, the full complement of ISIM flight instruments, structure, harness radiator, and electronics were put through a comprehensive program of thermal, optical, electrical, and operational tests. The test verified the health and excellent performance of the instruments and ISIM systems, proving the ISIM element's readiness for integration with the telescope. We report here on the context, goals, setup, execution, and key results for this critical JWST milestone.

  19. 利用声发射技术检测储罐的腐蚀损伤状态%Acoustic Emission Testing Technology for the Corrosion Destruction Condition of Vessels

    Institute of Scientific and Technical Information of China (English)

    钟建强; 柳颖; 杨娟; 王汉功

    2011-01-01

    The study is made to prove the feasibility of using the acoustic emission technology to detect tbe corrosion destruction condition of the liquid rocket oxidant vessels, whose main structure material is 5A03 aluminum alloy. The simulative test project using different concentrations of nitric acid to corrode 5A03 alloy is made according to the corrosion mechanism of the oxidant vessels in use. The corrosion process of 5A03 aluminium alloy is monitored by the acoustic emission technology for the first time in this article. The results show that the hits number can reflect the corrosion destruction condition of the alloy, and the distribution of the characteristic parameters, such as rise time, duration, ring-down counts and energy, is different obviously, and can be differed by 90% distribution interval. At last, the BP artificial neural network is build up to judge the corrosion damage degree with high accuracy, and the acoustic emission technology is proved feasible and predominant to inspect the corrosion condition of the oxidant vessel.%研究了采用声发射技术检测大型氧化剂储罐腐蚀损伤状态的可行性。根据液体火箭氧化剂储罐主要的结构材料5A03铝合金在实际使用中的腐蚀机理,选取不同浓度的硝酸作为腐蚀介质,建立5A03铝合金腐蚀的试验方案,利用声发射技术对腐蚀过程进行监测,获得了各浓度水平下的声发射信号。试验结果表明,声发射信号撞击数的多少能够反映合金不同的腐蚀损伤程度,不同浓度硝酸中5A03铝合金腐蚀声发射信号的上升时间、持续时间、振铃计数、能量等特征参数的分布具有较大差异,可通过90%的分布区间加以区分。利用所建立的BP神经网络能够以很高的正确率对5A03铝合金储罐腐蚀损伤程度进行模式识别。

  20. A low cost setup for behavioral audiometry in rodents.

    Science.gov (United States)

    Tziridis, Konstantin; Ahlf, Sönke; Schulze, Holger

    2012-10-16

    In auditory animal research it is crucial to have precise information about basic hearing parameters of the animal subjects that are involved in the experiments. Such parameters may be physiological response characteristics of the auditory pathway, e.g. via brainstem audiometry (BERA). But these methods allow only indirect and uncertain extrapolations about the auditory percept that corresponds to these physiological parameters. To assess the perceptual level of hearing, behavioral methods have to be used. A potential problem with the use of behavioral methods for the description of perception in animal models is the fact that most of these methods involve some kind of learning paradigm before the subjects can be behaviorally tested, e.g. animals may have to learn to press a lever in response to a sound. As these learning paradigms change perception itself (1,2) they consequently will influence any result about perception obtained with these methods and therefore have to be interpreted with caution. Exceptions are paradigms that make use of reflex responses, because here no learning paradigms have to be carried out prior to perceptual testing. One such reflex response is the acoustic startle response (ASR) that can highly reproducibly be elicited with unexpected loud sounds in naïve animals. This ASR in turn can be influenced by preceding sounds depending on the perceptibility of this preceding stimulus: Sounds well above hearing threshold will completely inhibit the amplitude of the ASR; sounds close to threshold will only slightly inhibit the ASR. This phenomenon is called pre-pulse inhibition (PPI) (3,4), and the amount of PPI on the ASR gradually depends on the perceptibility of the pre-pulse. PPI of the ASR is therefore well suited to determine behavioral audiograms in naïve, non-trained animals, to determine hearing impairments or even to detect possible subjective tinnitus percepts in these animals. In this paper we demonstrate the use of this method in a

  1. Theoretical study on setup of expanded-base pile considering cavity contraction

    Institute of Scientific and Technical Information of China (English)

    齐昌广; 刘干斌; 王艳; 邓岳保

    2015-01-01

    When an expanded-base pile is installed into ground, the cavity expansion associated with penetration of the enlarged pile base is followed by cavity contraction along the smaller-diameter pile shaft. In order to account for the influence of cavity contraction on the change of bearing capacity of expanded-base pile, a theoretical calculation methodology, predicting the setup of expanded-base pile, was established by employing the cavity contraction theory to estimate the shaft resistance of expanded-base pile, and horizontal consolidation theory to predict the dissipation of excess pore pressure. Finally, the numerical solutions for the setup of expanded-base pile were obtained. The parametric study about the influence of cavity contraction on setup of expanded-base pile was carried out, while a field test was introduced. The parametric study shows that the decrements in radial pressure and the maximum pore water pressure after considering cavity contraction are increased as the expanded ratio (base diameter/shaft diameter) and rigidity index of soil are raised. The comparison between calculated and measured values shows that the calculated results of ultimate bearing capacity for expanded-base pile considering cavity contraction agree well with the measured values; however, the computations ignoring cavity contraction are 2.5−3.0 times the measured values.

  2. Theoretical study on setup of expanded-base pile considering cavity contraction

    Institute of Scientific and Technical Information of China (English)

    齐昌广; 刘干斌; 王艳; 邓岳保

    2015-01-01

    When an expanded-base pile is installed into ground, the cavity expansion associated with penetration of the enlarged pile base is followed by cavity contraction along the smaller-diameter pile shaft. In order to account for the influence of cavity contraction on the change of bearing capacity of expanded-base pile, a theoretical calculation methodology, predicting the setup of expanded-base pile, was established by employing the cavity contraction theory to estimate the shaft resistance of expanded-base pile, and horizontal consolidation theory to predict the dissipation of excess pore pressure. Finally, the numerical solutions for the setup of expanded-base pile were obtained. The parametric study about the influence of cavity contraction on setup of expanded-base pile was carried out, while a field test was introduced. The parametric study shows that the decrements in radial pressure and the maximum pore water pressure after considering cavity contraction are increased as the expanded ratio(base diameter/shaft diameter) and rigidity index of soil are raised. The comparison between calculated and measured values shows that the calculated results of ultimate bearing capacity for expanded-base pile considering cavity contraction agree well with the measured values; however, the computations ignoring cavity contraction are 2.5-3.0 times the measured values.

  3. A setup for transmission measurements of low energy multiply charged ions through free-standing few atomic layer films

    Science.gov (United States)

    Smejkal, V.; Gruber, E.; Wilhelm, R. A.; Brandl, L.; Heller, R.; Facsko, S.; Aumayr, F.

    2016-09-01

    We report the design and testing of a setup for transmission measurements of multiply charged ions through free-standing films with a thickness of a few atomic layers. The investigation thereof can yield deeper insight into charge equilibration and pre-equilibrium stopping phenomena which can ultimately be used to specifically tailor and modify these materials.

  4. Makespan Minimization for The Identical Machine Parallel Shop with Sequence Dependent Setup Times Using a Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Salazar-Hornig E.

    2013-01-01

    Full Text Available A genetic algorithm for the parallel shop with identical machines scheduling problem with sequence dependent setup times and makespan (Cmáx minimization is presented. The genetic algorithm is compared with other heuristic methods using a randomly generated test problem set. A local improvement procedure in the evolutionary process of the genetic algorithm is introduced, which significantly improves its performance.

  5. Headspace-free setup of in vitro bioassays for the evaluation of volatile disinfection by-products.

    Science.gov (United States)

    Stalter, Daniel; Dutt, Mriga; Escher, Beate I

    2013-11-18

    The conventional setup of in vitro bioassays in microplates does not prevent the loss of volatile compounds, which hampers the toxicological characterization of waterborne volatile disinfection by-products (DBPs). To minimize the loss of volatile test chemicals, we adapted four in vitro bioassays to a headspace-free setup using eight volatile organic compounds (four trihalomethanes, 1,1-dichloroethene, bromoethane, and two haloacetonitriles) that cover a wide range of air-water partition coefficients. The nominal effect concentrations of the test chemicals decreased by up to three orders of magnitude when the conventional setup was changed to a headspace-free setup for the bacterial cytotoxicity assay using bioluminescence inhibition of Vibrio fischeri. The increase of apparent sensitivity correlated significantly with the air-water partition coefficient. Purge and trap GC/MS analysis revealed a reduced loss of dosed volatile compounds in the headspace free setup (78-130% of nominal concentration) compared to a substantial loss in the conventional set up (2-13% of the nominal concentration). The experimental effect concentrations converged with the headspace-free setup to the effect concentrations predicted by a QSAR model, confirming the suitability of the headspace-free approach to minimize the loss of volatile test chemicals. The analogue headspace-free design of the bacterial bioassays for genotoxicity (umuC assay) and mutagenicity (Ames fluctuation assay) increased the number of compounds detected as genotoxic or mutagenic from one to four and zero to two, respectively. In a bioassay with a mammalian cell line applied for detecting the induction of the Nrf-2-mediated oxidative stress response (AREc32 assay), the headspace-free setup improved the apparent sensitivity by less than one order of magnitude, presumably due to the retaining effect of the serum components in the medium, which is also reflected in the reduced aqueous concentrations of compounds. This

  6. TANGRA-Setup for the Investigation of Nuclear Fission induced by 14.1 MeV neutrons

    OpenAIRE

    RUSKOV I.; Kopatch, Y; BYSTRITSKY V.; Skoy, V.; SHVETSOV V.; Hambsch, Franz-Josef; Oberstedt, Stephan; CAPOTE NOY R.; Sedyshev, P.; GROZDANOV D.; IVANOV I. Zh.; ALEKSAKHIN V. Yu.; BOGOLUBOV E. P.; BARMAKOV Y.; Khabarov, S. V.

    2015-01-01

    The new experimental setup TANGRA (Tagged Neutrons & Gamma Rays), for the investigation of neutron induced nuclear reactions, e.g. (n,xn’), (n,xn’γ), (n,γ), (n,f), on a number of important isotopes for nuclear science and engineering (235,238U, 237Np, 239Pu, 244,245,248Cm) is under construction and being tested at the Frank Laboratory of Neutron Physics (FLNP) of the Joint Institute for Nuclear Research (JINR) in Dubna. The TANGRA setup consists of: a portable neutron generator ING-27, wit...

  7. An Acoustic Demonstration Model for CW and Pulsed Spectrosocopy Experiments

    Science.gov (United States)

    Starck, Torben; Mäder, Heinrich; Trueman, Trevor; Jäger, Wolfgang

    2009-06-01

    High school and undergraduate students have often difficulties if new concepts are introduced in their physics or chemistry lectures. Lecture demonstrations and references to more familiar analogues can be of great help to the students in such situations. We have developed an experimental setup to demonstrate the principles of cw absorption and pulsed excitation - emission spectroscopies, using acoustical analogues. Our radiation source is a speaker and the detector is a microphone, both controlled by a computer sound card. The acoustical setup is housed in a plexiglas box, which serves as a resonator. It turns out that beer glasses are suitable samples; this also helps to keep the students interested! The instrument is controlled by a LabView program. In a cw experiment, the sound frequency is swept through a certain frequency range and the microphone response is recorded simultaneously as function of frequency. A background signal without sample is recorded, and background subtraction yields the beer glass spectrum. In a pulsed experiment, a short sound pulse is generated and the microphone is used to record the resulting emission signal of the beer glass. A Fourier transformation of the time domain signal gives then the spectrum. We will discuss the experimental setup and show videos of the experiments.

  8. Safety Assessment of the Tank Bottom Corrosion Based on Acoustic Emission Testing%基于声发射检测的罐底腐蚀安全评估

    Institute of Scientific and Technical Information of China (English)

    白晟; 杨剑锋; 刘文彬; 许凤旌

    2013-01-01

    Atmospheric storage tank leaks often result in personal injury or death, property damage and environmental pollution and other serious consequences. So the safety assessment of the storage tank is particularly important. Existing detection methods have many shortcomings, such as time-consuming and easily missed, and low economic returns. In this article, the high reliability and convenience of acoustic emission online detection technology applied into the tank bottom corrosion were illustrated, the reasons for the formation of mechanical noise, ambient noise and electromagnetic noise were explained,and the corresponding filter methods were put forward, the process and the basis for evaluation of the safety assessment of the tank bottom corrosion based on acoustic emission testing were described, and the tank was evaluated.%常压储罐一旦发生泄漏,往往会造成人员伤亡、财产损失和环境污染等严重后果,因此对于储罐的安全评估尤为重要。现有的检测方法存在耗时长、易漏检、经济效益低等不足之处。以实例说明了声发射在线检测技术应用于罐底腐蚀检测的高可靠性与便捷性;解释了机械噪声、环境噪声以及电磁噪声形成的原因,并提出了相应的滤除方法;描述了基于声发射检测的罐底腐蚀安全评估的过程与评价依据,并进行评估。

  9. Dynamic response analysis of an aircraft structure under thermal-acoustic loads

    Science.gov (United States)

    Cheng, H.; Li, H. B.; Zhang, W.; Wu, Z. Q.; Liu, B. R.

    2016-09-01

    Future hypersonic aircraft will be exposed to extreme combined environments includes large magnitude thermal and acoustic loads. It presents a significant challenge for the integrity of these vehicles. Thermal-acoustic test is used to test structures for dynamic response and sonic fatigue due to combined loads. In this research, the numerical simulation process for the thermal acoustic test is presented, and the effects of thermal loads on vibro-acoustic response are investigated. To simulate the radiation heating system, Monte Carlo theory and thermal network theory was used to calculate the temperature distribution. Considering the thermal stress, the high temperature modal parameters are obtained with structural finite element methods. Based on acoustic finite element, modal-based vibro-acoustic analysis is carried out to compute structural responses. These researches are very vital to optimum thermal-acoustic test and structure designs for future hypersonic vehicles structure

  10. Constitutive relationship of ionic polymer-metal composite and static response character of its cantilever setup to voltage

    Institute of Scientific and Technical Information of China (English)

    TANG Hua-ping; NIE Tuo; TANG Yun-jun; YIN Chen-feng; TANG Chun-xi; WANG Qiao-yi

    2008-01-01

    As a new ionic polymer-metal composite (IPMC) for artificial muscle, the mechanical performance parameters and the relationship between the deformation and the electrical parameters of the IPMC were studied. With the digital speckle correlation method, the constitutive relationship of the IPMC was confirmed. With non-contact photography measurement, a cantilever setup was designed to confirm the relationship between the deformation of the IPMC film and the applied voltage. The relationship curve of tip displacement of the IPMC cantilever setup vs the voltage was achieved. The results indicate that the IPMC is isotropic, its elastic modulus is 232 MPa and Poisson ratio is 0.163. The curve achieved from the test of the tip displacement of the IPMC cantilever setup shows that the tip displacement reaches the maximum when the stimulated voltage is 5 V. And the tip displacement descends largely when the frequency of the applied voltage is between 30 mHz and 100 mHz.

  11. Acoustic Igniter Project

    Data.gov (United States)

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

  12. Acoustic imaging system

    Science.gov (United States)

    Kendall, J. M., Jr.

    1977-01-01

    Tool detects noise sources by scanning sound "scene" and displaying relative location of noise-producing elements in area. System consists of ellipsoidal acoustic mirror and microphone and a display device.

  13. 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.

  14. An acoustic invisible gateway

    CERN Document Server

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

    2015-01-01

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

  15. 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...

  16. 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...

  17. Symptoms of Acoustic Neuroma

    Science.gov (United States)

    ... Programs & Services Search ANAUSA.org Connect with us! Symptoms of Acoustic Neuroma Each heading slides to reveal more information. Early Symptoms Early Symptoms Early symptoms are easily overlooked, thus making diagnosis ...

  18. A System for Acoustic Field Measurement Employing Cartesian Robot

    Directory of Open Access Journals (Sweden)

    Szczodrak Maciej

    2016-09-01

    Full Text Available A system setup for measurements of acoustic field, together with the results of 3D visualisations of acoustic energy flow are presented in the paper. Spatial sampling of the field is performed by a Cartesian robot. Automatization of the measurement process is achieved with the use of a specialized control system. The method is based on measuring the sound pressure (scalar and particle velocity(vector quantities. The aim of the system is to collect data with a high precision and repeatability. The system is employed for measurements of acoustic energy flow in the proximity of an artificial head in an anechoic chamber. In the measurement setup an algorithm for generation of the probe movement path is included. The algorithm finds the optimum path of the robot movement, taking into account a given 3D object shape present in the measurement space. The results are presented for two cases, first without any obstacle and the other - with an artificial head in the sound field.

  19. Hybrid CFD/CAA Modeling for Liftoff Acoustic Predictions

    Science.gov (United States)

    Strutzenberg, Louise L.; Liever, Peter A.

    2011-01-01

    This paper presents development efforts at the NASA Marshall Space flight Center to establish a hybrid Computational Fluid Dynamics and Computational Aero-Acoustics (CFD/CAA) simulation system for launch vehicle liftoff acoustics environment analysis. Acoustic prediction engineering tools based on empirical jet acoustic strength and directivity models or scaled historical measurements are of limited value in efforts to proactively design and optimize launch vehicles and launch facility configurations for liftoff acoustics. CFD based modeling approaches are now able to capture the important details of vehicle specific plume flow environment, identifY the noise generation sources, and allow assessment of the influence of launch pad geometric details and sound mitigation measures such as water injection. However, CFD methodologies are numerically too dissipative to accurately capture the propagation of the acoustic waves in the large CFD models. The hybrid CFD/CAA approach combines the high-fidelity CFD analysis capable of identifYing the acoustic sources with a fast and efficient Boundary Element Method (BEM) that accurately propagates the acoustic field from the source locations. The BEM approach was chosen for its ability to properly account for reflections and scattering of acoustic waves from launch pad structures. The paper will present an overview of the technology components of the CFD/CAA framework and discuss plans for demonstration and validation against test data.

  20. Anal acoustic reflectometry

    DEFF Research Database (Denmark)

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

    2011-01-01

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