Science.gov

Sample records for energy experimental results

  1. Energy-resolved computed tomography: first experimental results

    NASA Astrophysics Data System (ADS)

    Shikhaliev, Polad M.

    2008-10-01

    First experimental results with energy-resolved computed tomography (CT) are reported. The contrast-to-noise ratio (CNR) in CT has been improved with x-ray energy weighting for the first time. Further, x-ray energy weighting improved the CNR in material decomposition CT when applied to CT projections prior to dual-energy subtraction. The existing CT systems use an energy (charge) integrating x-ray detector that provides a signal proportional to the energy of the x-ray photon. Thus, the x-ray photons with lower energies are scored less than those with higher energies. This underestimates contribution of lower energy photons that would provide higher contrast. The highest CNR can be achieved if the x-ray photons are scored by a factor that would increase as the x-ray energy decreases. This could be performed by detecting each x-ray photon separately and measuring its energy. The energy selective CT data could then be saved, and any weighting factor could be applied digitally to a detected x-ray photon. The CT system includes a photon counting detector with linear arrays of pixels made from cadmium zinc telluride (CZT) semiconductor. A cylindrical phantom with 10.2 cm diameter made from tissue-equivalent material was used for CT imaging. The phantom included contrast elements representing calcifications, iodine, adipose and glandular tissue. The x-ray tube voltage was 120 kVp. The energy selective CT data were acquired, and used to generate energy-weighted and material-selective CT images. The energy-weighted and material decomposition CT images were generated using a single CT scan at a fixed x-ray tube voltage. For material decomposition the x-ray spectrum was digitally spilt into low- and high-energy parts and dual-energy subtraction was applied. The x-ray energy weighting resulted in CNR improvement of calcifications and iodine by a factor of 1.40 and 1.63, respectively, as compared to conventional charge integrating CT. The x-ray energy weighting was also applied

  2. Comments on experimental results of energy confinement of tokamak plasmas

    SciTech Connect

    Chu, T.K.

    1989-04-01

    The results of energy-confinement experiments on steady-state tokamak plasmas are examined. For plasmas with auxiliary heating, an analysis based on the heat diffusion equation is used to define heat confinement time (the incremental energy confinement time). For ohmically sustained plasmas, experiments show that the onset of the saturation regime of energy confinement, marfeing, detachment, and disruption are marked by distinct values of the parameter /bar n//sub e///bar j/. The confinement results of the two types of experiments can be described by a single surface in 3-dimensional space spanned by the plasma energy, the heating power, and the plasma density: the incremental energy confinement time /tau//sub inc/ = ..delta..W/..delta..P is the correct concept for describing results of heat confinement in a heating experiment; the commonly used energy confinement time defined by /tau//sub E/ = W/P is not. A further examination shows that the change of edge parameters, as characterized by the change of the effective collision frequency ..nu../sub e/*, governs the change of confinement properties. The totality of the results of tokamak experiments on energy confinement appears to support a hypothesis that energy transport is determined by the preservation of the pressure gradient scale length. 70 refs., 6 figs., 1 tab.

  3. High energy imploding liner experiment HEL-1: Experimental results

    SciTech Connect

    Clark, D.A.; Anderson, B.G.; Ekdahl, C.A.

    1997-09-01

    Magnetically driven imploding liner systems can be used as a source of shock energy for materials equation of state studies, implosion driven magnetized plasma fusion experiments, and other similar applications. The imploding liner is a cylinder of conducting material through which a current is passed in the longitudinal direction. Interaction of the current with its own magnetic field causes the liner to implode. Sources of electrical energy for imploding liner systems are capacitor banks or explosive pulse power systems seeded by capacitor banks. In August, 1996, a high energy liner experiment (HEL-1) was conducted at the All-Russia Scientific Research Institute (VNIIEF) in Sarov, Russia. A 5 tier 1 meter diameter explosive disk generator provided electrical energy to drive a 48 cm outside diameter, 4 mm thick, aluminum alloy liner having a mass of about 11kg onto an 11 cm diameter diagnostic package. The purpose of the experiment was to measure performance of the explosive pulse power generator and the heavy imploding liner. Electrical performance diagnostics included inductive (B-dot) probes, Faraday Rotation current measurement, Rogowski total current measurement, and voltage probes. Flux loss and conductor motion diagnostics included current-joint voltage measurements and motion sensing contact pins. Optical and electrical impact pins, inductive (B-dot) probes, manganin pressure probes, and continuously recording resistance probes in the Central Measuring Unit (CMU) and Piezo and manganin pressure probes, optical beam breakers, and inductive probes located in the glide planes were used as liner symmetry and velocity diagnostics. Preliminary analysis of the data indicate that a peak current of more than 100 MA was attained and the liner velocity was between 6.7 km/sec and 7.5 km/sec. Liner kinetic energy was between 22 MJ and 35 MJ. 4 refs., 6 figs., 1 tab.

  4. Experimental results from CERN on reaction mechanisms in high energy heavy ion collisions

    SciTech Connect

    Sorensen, S.P. Tennessee Univ., Knoxville, TN . Dept. of Physics)

    1990-01-01

    Three main experimental results from CERN concerning reaction mechanisms in high energy heavy ion collisions are discussed: (1) the striking validity of the single particle picture, (2) the nuclear stopping power and (3) the attained energy densities.

  5. Preliminary results of the large experimental wind turbine phase of the national wind energy program

    NASA Technical Reports Server (NTRS)

    Thomas, R. L.; Sholes, T.; Sholes, J. E.

    1975-01-01

    The preliminary results of two projects in the development phase of reliable wind turbines designed to supply cost-competitive electrical energy were discussed. An experimental 100 kW wind turbine design and its status are first reviewed. The results of two parallel design studies for determining the configurations and power levels for wind turbines with minimum energy costs are also discussed. These studies predict wind energy costs of 1.5 to 7 cents per kW-h for wind turbines produced in quantities of 100 to 1000 per year and located at sites having average winds of 12 to 18 mph.

  6. Experimental Results From the Thermal Energy Storage-1 (TES-1) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Jacqmin, David

    1995-01-01

    The Thermal Energy Storage (TES) experiments are designed to provide data to help researchers understand the long-duration microgravity behavior of thermal energy storage fluoride salts that undergo repeated melting and freezing. Such data, which have never been obtained before, have direct application to space-based solar dynamic power systems. These power systems will store solar energy in a thermal energy salt, such as lithium fluoride (LiF) or a eutectic of lithium fluoride/calcium difluoride (LiF-CaF2) (which melts at a lower temperature). The energy will be stored as the latent heat of fusion when the salt is melted by absorbing solar thermal energy. The stored energy will then be extracted during the shade portion of the orbit, enabling the solar dynamic power system to provide constant electrical power over the entire orbit. Analytical computer codes have been developed to predict the performance of a spacebased solar dynamic power system. However, the analytical predictions must be verified experimentally before the analytical results can be used for future space power design applications. Four TES flight experiments will be used to obtain the needed experimental data. This article focuses on the flight results from the first experiment, TES-1, in comparison to the predicted results from the Thermal Energy Storage Simulation (TESSIM) analytical computer code.

  7. Preliminary results of the large experimental wind turbine phase of the national wind energy program

    NASA Technical Reports Server (NTRS)

    Thomas, R. L.; Sholes, J. E.

    1975-01-01

    A major phase of the wind energy program is the development of reliable wind turbines for supplying cost-competitive electrical energy. This paper discusses the preliminary results of two projects in this phase of the program. First an experimental 100 kW wind turbine design and its status are reviewed. Also discussed are the results of two parallel design studies for determining the configurations and power levels for wind turbines with minimum energy costs. These studies show wind energy costs of 7 to 1.5 c/kWH for wind turbines produced in quantities of 100 to 1000 a year and located at sites having average winds of 12 to 18 mph.

  8. Optimal piezoelectric beam shape for single and broadband vibration energy harvesting: Modeling, simulation and experimental results

    NASA Astrophysics Data System (ADS)

    Muthalif, Asan G. A.; Nordin, N. H. Diyana

    2015-03-01

    Harvesting energy from the surroundings has become a new trend in saving our environment. Among the established ones are solar panels, wind turbines and hydroelectric generators which have successfully grown in meeting the world's energy demand. However, for low powered electronic devices; especially when being placed in a remote area, micro scale energy harvesting is preferable. One of the popular methods is via vibration energy scavenging which converts mechanical energy (from vibration) to electrical energy by the effect of coupling between mechanical variables and electric or magnetic fields. As the voltage generated greatly depends on the geometry and size of the piezoelectric material, there is a need to define an optimum shape and configuration of the piezoelectric energy scavenger. In this research, mathematical derivations for unimorph piezoelectric energy harvester are presented. Simulation is done using MATLAB and COMSOL Multiphysics software to study the effect of varying the length and shape of the beam to the generated voltage. Experimental results comparing triangular and rectangular shaped piezoelectric beam are also presented.

  9. Experimental Results from the Thermal Energy Storage-1 (TES-1) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Wald, Lawrence W.; Tolbert, Carol; Jacqmin, David

    1995-01-01

    The Thermal Energy Storage-1 (TES-1) is a flight experiment that flew on the Space Shuttle Columbia (STS-62), in March 1994, as part of the OAST-2 mission. TES-1 is the first experiment in a four experiment suite designed to provide data for understanding the long duration microgravity behavior of thermal energy storage fluoride salts that undergo repeated melting and freezing. Such data have never been obtained before and have direct application for the development of space-based solar dynamic (SD) power systems. These power systems will store solar energy in a thermal energy salt such as lithium fluoride or calcium fluoride. The stored energy is extracted during the shade portion of the orbit. This enables the solar dynamic power system to provide constant electrical power over the entire orbit. Analytical computer codes have been developed for predicting performance of a spaced-based solar dynamic power system. Experimental verification of the analytical predictions is needed prior to using the analytical results for future space power design applications. The four TES flight experiments will be used to obtain the needed experimental data. This paper will focus on the flight results from the first experiment, TES-1, in comparison to the predicted results from the Thermal Energy Storage Simulation (TESSIM) analytical computer code. The TES-1 conceptual development, hardware design, final development, and system verification testing were accomplished at the NASA lewis Research Center (LeRC). TES-1 was developed under the In-Space Technology Experiment Program (IN-STEP), which sponsors NASA, industry, and university flight experiments designed to enable and enhance space flight technology. The IN-STEP Program is sponsored by the Office of Space Access and Technology (OSAT).

  10. Experimental Results from the Thermal Energy Storage-2 (TES-2) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Tolbert, Carol

    2000-01-01

    Thermal Energy Storage-2 (TES-2) is a flight experiment that flew on the Space Shuttle Endeavour (STS-72), in January 1996. TES-2 originally flew with TES-1 as part of the OAST-2 Hitchhiker payload on the Space Shuttle Columbia (STS-62) in early 1994. The two experiments, TES-1 and TES-2 were identical except for the fluoride salts to be characterized. TES-1 provided data on lithium fluoride (LiF), TES-2 provided data on a fluoride eutectic (LiF/CaF2). Each experiment was a complex autonomous payload in a Get-Away-Special payload canister. TES-1 operated flawlessly for 22 hr. Results were reported in a paper entitled, Effect of Microgravity on Materials Undergoing Melting and Freezing-The TES Experiment, by David Namkoong et al. A software failure in TES-2 caused its shutdown after 4 sec of operation. TES-1 and 2 were the first experiments in a four experiment suite designed to provide data for understanding the long duration microgravity behavior of thermal energy storage salts that undergo repeated melting and freezing. Such data have never been obtained before and have direct application for the development of space-based solar dynamic (SD) power systems. These power systems will store energy in a thermal energy salt such as lithium fluoride or a eutectic of lithium fluoride/calcium difluoride. The stored energy is extracted during the shade portion of the orbit. This enables the solar dynamic power system to provide constant electrical power over the entire orbit. Analytical computer codes were developed for predicting performance of a space-based solar dynamic power system. Experimental verification of the analytical predictions were needed prior to using the analytical results for future space power design applications. The four TES flight experiments were to be used to obtain the needed experimental data. This paper will address the flight results from the first and second experiments, TES-1 and 2, in comparison to the predicted results from the Thermal

  11. SAA drift: Experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Romashova, V. V.; Petrov, A. N.

    According to the paleomagnetic analysis there are variations of Earth’s magnetic field connected with magnetic moment changing. These variations affect on the South Atlantic Anomaly (SAA) location. Indeed different observations approved the existence of the SAA westward drift rate (0.1 1.0 deg/year) and northward drift rate (approximately 0.1 deg/year). In this work, we present the analysis of experimental results obtained in Scobeltsyn Institute of Nuclear Physics, Moscow State University (SINP MSU) onboard different Earth’s artificial satellites (1972 2003). The fluxes of protons with energy >50 MeV, gamma quanta with energy >500 keV and neutrons with energy 0.1 1.0 MeV in the SAA region have been analyzed. The mentioned above experimental data were obtained onboard the orbital stations Salut-6 (1979), MIR (1991, 1998) and ISS (2003) by the similar experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact that the SAA drifts westward. Moreover the analysis of fluxes of electrons with energy about hundreds keV (Cosmos-484 (1972) and Active (Interkosmos-24, 1991) satellites) verified not only the SAA westward drift but northward drift also.

  12. Energy Transfer with Hydrogen and Superconductivity - The Review of the First Experimental Results

    NASA Astrophysics Data System (ADS)

    Vysotsky, V. S.; Antyukhov, I. V.; Firsov, V. P.; Blagov, E. V.; Kostyuk, V. V.; Nosov, A. A.; Fetisov, S. S.; Zanegin, S. Yu.; Rachuk, V. S.; Katorgin, B. I.

    The transfer of massive amounts of both electrical and chemical power over long distances will present a major challenge for the global energy enterprise in future. Attraction of hydrogen is apparent as a chemical energy agent, possessing among the highest energy density content of various common fuels, whose combustive "waste" is simply water. The usage of "gratis" cold to cool a superconducting cable made of proper superconductor permits to deliver extra electrical power with the same line. This, rather old theoretical idea recently found its experimental realization. The team of Russian institutes and organizations with using Italian-produced MgB2 wire has made and successfully tested two hybrid energy transfer lines with liquid hydrogen as a chemical source of power and superconducting cable as a source of electricity. The first line has been tested in 2011. It has length ∼10 m, maximum liquid hydrogen flow ∼250 g/s and maximum current of MgB2 superconducting cable 2600 A @ 20K. This test was the first experimental proof of conception of the hybrid energy transfer line. The second line has been tested in October 2013. It has length ∼30 m. The new MgB2 cable has critical current at 21 K ∼3500 A and successfully passed high voltage DC test of 50 kV. New hydrogen cryostat has three sections with different types of thermal insulation in each section. The idea of hybrid energy transfer is formulated and details of first experiments are reviewed.

  13. Heating stents with radio frequency energy to prevent tumor ingrowth: modeling and experimental results

    NASA Astrophysics Data System (ADS)

    Ryan, Thomas P.; Lawes, Kate; Goldberg, S. Nahum

    1998-04-01

    Stents are often inserted into internal orifices to treat blockage due to tumor ingrowth. Stents are favored due to their minimally invasive nature, possible avoidance of a surgical procedure, and their ability to palliate surgically non-resectable disease. Because of rapid tumor growth however, a treatment means to prevent overgrowth through the stent and resultant blockage is required. To further this goal, experiments were performed in which a stent was placed in tissue and heated with radiofrequency (RF) energy to coagulate a cylinder of tissue, thereby eradicating viable tissue in the proximity of the stent. Temperatures were measured at the central stent surface and edges over time during a 5 - 10 minute heating in phantom and in fresh tissue. In addition, a finite element model was used to simulate the electric field and temperature distribution. Blood flow was also introduced in the model by evaluating RF application to stents to determine effectiveness of the energy applications. Changing perfusion and tissue electrical conductivity as a function of temperature was applied as the tissue was heated to 100 degree(s)C. Results from the electric field model will be shown as well as the thermal distribution over time from the simulations. Lastly, results from the damage integral will be discussed.

  14. U.S. Department of Energy Reference Model Program RM1: Experimental Results

    SciTech Connect

    Hill, Craig; Neary, Vincent Sinclair; Gunawan, Budi; Guala, Michele; Sotiropoulos, Fotis

    2014-10-01

    The Reference Model Project (RMP), sponsored by the U.S. Department of Energy’s (DOE) Wind and Water Power Technologies Program within the Office of Energy Efficiency & Renewable Energy (EERE), aims at expediting industry growth and efficiency by providing non-proprietary Reference Models (RM) of MHK technology designs as study objects for open-source research and development (Neary et al. 2014a,b). As part of this program, MHK turbine models were tested in a large open channel facility at the University of Minnesota’s St. Anthony Falls Laboratory (UMN-SAFL). Reference Model 1 (RM2) is a 1:40 geometric scale dual-rotor axial flow horizontal axis device with counter-rotating rotors, each with a rotor diameter dT = 0.5m. Precise blade angular position and torque measurements were synchronized with three acoustic Doppler velocimeters (ADVs) aligned with each rotor and the midpoint for RM1. Flow conditions for each case were controlled such that depth, h = 1m, and volumetric flow rate, Qw = 2.425m3s-1, resulting in a hub height velocity of approximately Uhub = 1.05ms-1 and blade chord length Reynolds numbers of Rec ≈ 3.0x105. Vertical velocity profiles collected in the wake of each device from 1 to 10 rotor diameters are used to estimate the velocity recovery and turbulent characteristics in the wake, as well as the interaction of the counter-rotating rotor wakes. The development of this high resolution laboratory investigation provides a robust dataset that enables assessing turbulence performance models and their ability to accurately predict device performance metrics, including computational fluid dynamics (CFD) models that can be used to predict turbulent inflow environments, reproduce wake velocity deficit, recovery and higher order turbulent statistics, as well as device performance metrics.

  15. Energy performance of an architectural fabric roof: Experimental and analytical results

    SciTech Connect

    Gridley, R.B.; Hart, G.H.; Goss, W.P.

    1985-01-01

    As part of a research program on the thermal performance of translucent fabric-covered buildings, a comparison between measured and predicted fabric roof heat transfer was made. Predictions, based on a steady-state ASHRAE calculation technique, were compared against measured heat transfer through three different roof systems operating under outside weather conditions. The goals of the study were to evaluate the ability to predict the net energy transfer through the fabric roof systems tested, to identify parameters that would contribute to major differences between the measured and predicted results, and to recommend improvements to those parameters. It is expected that those improvements could be made in the computer program, DOE-2. The heat transfer through a single-layer, a double-layer, and a translucent insulated fabric roof system was measured in a vertical heat flow, guarded hot box located outdoors in Granville, Ohio. The results obtained by comparing the measured and predicted net heat transfer through the three roof systems indicated that the ASHRAE calculational technique predicted heat loss to within +. 25%, but it consistently overpredicted the heat gain during cooling load situations.

  16. U.S. Department of Energy Reference Model Program RM2: Experimental Results

    SciTech Connect

    Hill, Craig; Neary, Vincent Sinclair; Gunawan, Budi; Guala, Michele; Sotiropoulos, Fotis

    2014-08-01

    The Reference Model Project (RMP), sponsored by the U.S. Department of Energy’s (DOE) Wind and Water Power Technologies Program within the Office of Energy Efficiency & Renewable Energy (EERE), aims at expediting industry growth and efficiency by providing non-proprietary Reference Models (RM) of MHK technology designs as study objects for open-source research and development (Neary et al. 2014a,b). As part of this program, MHK turbine models were tested in a large open channel facility at the University of Minnesota’s St. Anthony Falls Laboratory (UMN - SAFL) . Reference Model 2 (RM2) is a 1:15 geometric scale dual - rotor cross flow vertical axis device with counter - rotating rotors, each with a rotor diameter dT = 0.43m and rotor height, hT = 0.323 m. RM2 is a river turbine designed for a site modeled after a reach in the lower Mississippi River near Baton Rouge, Louisiana (Barone et al. 2014) . Precise blade angular position and torque measurements were synchronized with three acoustic Doppler velocimeters (ADV) aligned with each rotor and the midpoint for RM2 . Flow conditions for each case were controlled such that depth, h = 1m, and volumetric flow rate, Qw = 2. 35m3s-1 , resulting in a hub height velocity of approximately Uhub = 1. 2 ms-1 and blade chord length Reynolds numbers of Rec = 6 .1x104. Vertical velocity profiles collected in the wake of each device from 1 to 10 rotor diameters are used to estimate the velocity recovery and turbulent characteristics in the wake, as well as the interaction of the counter-rotating rotor wakes. The development of this high resolution laboratory investigation provides a robust dataset that enables assessing computational fluid dynamics (CFD) models and their ability to accurately simulate turbulent inflow environments, device performance metrics, and to reproduce wake velocity deficit, recovery and higher order

  17. Mechanism of Electromagnetic Energy Effects of the Nervous System. Experimental System and Preliminary Results.

    DTIC Science & Technology

    1982-07-01

    activity did not change when the EM field was turned on. Several experiments were performed to observe the neural response to an increase in...examined on 27 June 1980) not exposed to EM energy was exposed to tubo - curarine (curare), a synaptic inhibitor. Curare was used to isolate the cell

  18. High energy cosmic ray physics with underground muons in MACRO. I. Analysis methods and experimental results

    SciTech Connect

    Bellotti, R.; Cafagna, F.; Calicchio, M.; Castellano, M.; De Cataldo, G.; De Marzo, C.; Erriquez, O.; Favuzzi, C.; Fusco, P.; Giglietto, N.; Guarnaccia, P.; Mazziotta, M.N.; Montaruli, T.; Raino, A.; Spinelli, P.; Cecchini, S.; Dekhissi, H.; Fantini, R.; Giacomelli, G.; Mandrioli, G.; Margiotta-Neri, A.; Patrizii, L.; Popa, V.; Serra-Lugaresi, P.; Spurio, M.; Togo, V.; Hong, J.T.; Kearns, E.; Okada, C.; Orth, C.; Stone, J.L.; Sulak, L.R.; Barish, B.C.; Goretti, M.; Katsavounidis, E.; Kyriazopoulou, S.; Michael, D.G.; Nolty, R.; Peck, C.W.; Scholberg, K.; Walter, C.W.; Lane, C.; Steinberg, R.; Battistoni, G.; Bilokon, H.; Bloise, C.; Carboni, M.; Chiarella, V.; Forti, C.; Iarocci, E.; Marini, A.; Patera, V.; Ronga, F.; Satta, L.; Sciubba, A.; Spinetti, M.; Valente, V.; Antolini, R.; Bosio, T.; Di Credico, A.; Grillo, A.; Gustavino, C.; Mikheyev, S.; Parlati, S.; Reynoldson, J.; Scapparone, E.; Bower, C.; Habig, A.; Hawthorne, A.; Heinz, R.; Miller, L.; Mufson, S.; Musser, J.; De Mitri, I.; Monacelli, P.; Bernardini, P.; Mancarella, G.; Martello, D.; Palamara, O.; Petrera, S.; Pistilli, P.; Ricciardi, M.; Surdo, A.; Baker, R.; and others

    1997-08-01

    In this paper, the first of a two-part work, we present the reconstruction and measurement of muon events detected underground by the MACRO experiment at Gran Sasso (E{sub {mu}}{ge} 1.3 TeV in atmosphere). The main aim of this work is to discuss the muon multiplicity distribution as measured in the detector. The data sample analyzed consists of 4.4{times}10{sup 6} muon events, of which {approximately} 263000 are multiple muons, corresponding to a total live time of 5850 h. In this sample, the observed multiplicities extend above N{sub {mu}}=35, with intermuon separations up to 50 m and beyond. Additional complementing measurements, such as the inclusive muon flux, the angular distribution, and the muon separation distribution (decoherence), are also included. The physical interpretation of the results presented here is reported in the following companion paper. {copyright} {ital 1997} {ital The American Physical Society}

  19. Validation and verification of MCNP6 against intermediate and high-energy experimental data and results by other codes

    SciTech Connect

    Mashnik, Stepan G

    2010-11-22

    MCNP6, the latest and most advanced LANL transport code representing a recent merger of MCNP5 and MCNPX, has been Validated and Verified (V and V) against a variety of intermediate and high-energy experimental data and against results by different versions of MCNPX and other codes. In the present work, we V andV MCNP6 using mainly the latest modifications of the Cascade-Exciton Model (CEM) and of the Los Alamos version of the Quark-Gluon String Model (LAQGSM) event generators CEM03.02 and LAQGSM03.03. We found that MCNP6 describes reasonably well various reactions induced by particles and nuclei at incident energies from 18 MeV to about 1 TeV per nucleon measured on thin and thick targets and agrees very well with similar results obtained with MCNPX and calculations by CEM03.02, LAQGSM03.01 (03.03), INCL4 + ABLA, and Bertini INC + Dresner evaporation, EPAX, ABRABLA, HIPSE, and AMD, used as stand alone codes. Most of several computational bugs and more serious physics problems observed in MCNP6/X during our V and V have been fixed; we continue our work to solve all the known problems before MCNP6 is distributed to the public.

  20. SAA drift:experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Kudela, K.; Romashova, V. V.; Drozdov, A. Yu.

    According to the paleomagnetic analysis there are variations of Earth's magnetic field connected with magnetic momentum changing. Besides these variations affects on the trapped belt South Atlantic Anomaly (SAA) location. Indeed different observations including Space Shuttle short-time flights approved the existence SAA westward drift with speed 0.1-1.0 (deg/year) and northward drift with speed approximately 0.1 (deg/year). In this work we present the analysis of experimental results obtained in SINP MSU in 1972-2003 from different satellites. There were analyzed the fluxes of protons with energy > 50 MeV, gamma quanta with energy > 500 keV and neutrons with energy 0.1-1.0 MeV in SAA area and their maxima location. The data about fluxes were obtained onboard the orbital stations ``Salut-6'' (1979), MIR (1991, 1998) and ISS (2003) by the identical experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact of the SAA westward drift. Moreover the same analysis of maximum flux location of electrons with hundreds keV energy (satellites ``Kosmos-484'' (1972), ``Interkosmos-17'' (1977) and ``Activny'' (``Interkosmos-24'', 1991)) confirmed not only the SAA westward drift but northward drift also.

  1. Experimental Test Results of Energy Efficient Transport (EET) High-Lift Airfoil in Langley Low-Turbulence Pressure Tunnel

    NASA Technical Reports Server (NTRS)

    Morgan, Harry L., Jr.

    2002-01-01

    This report describes the results of an experimental study conducted in the Langley Low-Turbulence Pressure Tunnel to determine the effects of Reynolds number and Mach number on the two-dimensional aerodynamic performance of the Langley Energy Efficient Transport (EET) High-Lift Airfoil. The high-lift airfoil was a supercritical-type airfoil with a thickness-to- chord ratio of 0.12 and was equipped with a leading-edge slat and a double-slotted trailing-edge flap. The leading-edge slat could be deflected -30 deg, -40 deg, -50 deg, and -60 deg, and the trailing-edge flaps could be deflected to 15 deg, 30 deg, 45 deg, and 60 deg. The gaps and overlaps for the slat and flaps were fixed at each deflection resulting in 16 different configurations. All 16 configurations were tested through a Reynolds number range of 2.5 to 18 million at a Mach number of 0.20. Selected configurations were also tested through a Mach number range of 0.10 to 0.35. The plotted and tabulated force, moment, and pressure data are available on the CD-ROM supplement L-18221.

  2. Dielectric energy of orientation in dead and living cells of Schizosaccharomyces pombe. Fitting of experimental results to a theoretical model.

    PubMed Central

    Asencor, F J; Santamaría, C; Iglesias, F J; Domínguez, A

    1993-01-01

    Using the experimental data obtained with killed cells of Schizosaccharomyces pombe (1), we have formulated a theoretical model that is able to predict cell orientation for microorganisms with ellipsoidal or cylindrical shapes as a function of the frequency of the electric field and of the conductivity of the external medium. In this model, comparison of the difference in potential energy for both orientations parallel-perpendicular with the thermal agitation energy allows one to interpret the intervals where these orientations occur. The model implies that the conductivity of the cytoplasm is slightly higher than that of the external medium. This assumption is easy to understand taking into account that not all the intracytoplasmic material is released to the exterior during cell death. PMID:8324197

  3. Cleanroom energy benchmarking results

    SciTech Connect

    Tschudi, William; Xu, Tengfang

    2001-09-01

    A utility market transformation project studied energy use and identified energy efficiency opportunities in cleanroom HVAC design and operation for fourteen cleanrooms. This paper presents the results of this work and relevant observations. Cleanroom owners and operators know that cleanrooms are energy intensive but have little information to compare their cleanroom's performance over time, or to others. Direct comparison of energy performance by traditional means, such as watts/ft{sup 2}, is not a good indicator with the wide range of industrial processes and cleanliness levels occurring in cleanrooms. In this project, metrics allow direct comparison of the efficiency of HVAC systems and components. Energy and flow measurements were taken to determine actual HVAC system energy efficiency. The results confirm a wide variation in operating efficiency and they identify other non-energy operating problems. Improvement opportunities were identified at each of the benchmarked facilities. Analysis of the best performing systems and components is summarized, as are areas for additional investigation.

  4. Experimental Analysis of Heat Flux to a Blunt Body in Hypersonic Flow with Upstream Laser Energy Deposition — Preliminary Results

    NASA Astrophysics Data System (ADS)

    Salvador, I. I.; Minucci, M. A. S.; Toro, P. G. P.; Oliveira, A. C.; Channes, J. B.; Myrabo, L. N.; Nagamatsu, H. T.

    2006-05-01

    Due to high heat transfer rates in hypersonic flight and its consequent necessity of prohibitively massive thermal protection system, new methods of flow control are required to enable flight in such regimes. Here arises the Direct Energy Air Spike concept, where electromagnetic energy (laser/microwaves) is focalized upstream of the model causing the breakdown of the air and the generation of a Laser Supported Detonation wave which diverts the incoming stream parabolically. In this preliminary work, the heat transfer rates to the surface of a blunt body, downstream the laser induced shock wave, were qualitatively measured and compared with the results without the DEAS. These measurements were conducted with the use of fast response coaxial thermocouples and piezoelectric pressure transducers installed on the surface of the model in the 0.30m IEAv's T2 Hypersonic Shock Tunnel. The laser energy was supplied by a CO2 TEA Laser.

  5. A NEW DETERMINATION OF THE BINDING ENERGY OF ATOMIC OXYGEN ON DUST GRAIN SURFACES: EXPERIMENTAL RESULTS AND SIMULATIONS

    SciTech Connect

    He, Jiao; Shi, Jianming; Hopkins, Tyler; Vidali, Gianfranco; Kaufman, Michael J.

    2015-03-10

    The energy to desorb atomic oxygen from an interstellar dust grain surface, E{sub des}, is an important controlling parameter in gas-grain models; its value impacts the temperature range over which oxygen resides on a dust grain. However, no prior measurement has been done of the desorption energy. We report the first direct measurement of E{sub des} for atomic oxygen from dust grain analogs. The values of E{sub des} are 1660 ± 60 and 1850 ± 90 K for porous amorphous water ice and for a bare amorphous silicate film, respectively, or about twice the value previously adopted in simulations of the chemical evolution of a cloud. We use the new values to study oxygen chemistry as a function of depth in a molecular cloud. For n = 10{sup 4} cm{sup −3} and G{sub 0} = 10{sup 2} (G{sub 0} = 1 is the average local interstellar radiation field), the main result of the adoption of the higher oxygen binding energy is that H{sub 2}O can form on grains at lower visual extinction A{sub V}, closer to the cloud surface. A higher binding energy of O results in more formation of OH and H{sub 2}O on grains, which are subsequently desorbed by far-ultraviolet radiation, with consequences for gas-phase chemistry. For higher values of n and G{sub 0}, the higher binding energy can lead to a large increase in the column of H{sub 2}O but a decrease in the column of O{sub 2}.

  6. Asymptotic stabilisation of the ball and beam system: design of energy-based control law and experimental results

    NASA Astrophysics Data System (ADS)

    Muralidharan, Vijay; Anantharaman, S.; Mahindrakar, Arun D.

    2010-06-01

    We present a new nonlinear control law to stabilise the ball and beam system at a desired operating point. The control law is based on the interconnection and damping assignment-passivity-based control (IDA-PBC) methodology developed in Ortega, Spong, Gomez-Estern, and Blankenstien (Ortega, R., Spong, M., Gomez-Estern, F., and Blankenstien, G. (2002), 'Stabilization of Underactuated Mechanical Systems via Interconnection and Damping Assignment', IEEE Transactions on Automatic Control, 47, 1218-1233) that guarantees stability in the sense of Lyapunov. We present a novel proof of the asymptotic stability of the desired operating point. The validity of the proposed control law is demonstrated through the experimental results.

  7. Comparison of Model and Experimental Results for Material and Energy Flow in a Titanium Evaporation System with Deforming Interfaces

    SciTech Connect

    McClelland, M A; Westerberg, K W; Meier, T C; Braun, D G; Frischknecht, K D; Anklam, T M

    2003-05-12

    Finite element calculations and measurements are compared for material and energy flow in a system to evaporate pure titanium. A 40 kW electron beam is used to heat the end of a 7.62 cm diameter cylindrical rod which is fed vertically through a water-cooled crucible. Vapor emanates from a liquid pool in which flow is driven strongly by buoyancy and capillary forces. At high evaporation rates, the vapor exerts strong shear and normal forces on the liquid-vapor interface. The MELT finite element code is used to calculate steady-state, axisymmetric flow and temperature fields along with liquid-solid and liquid-vapor interface locations. The influence of the vapor on the liquid top surface is treated using boundary conditions with parameters derived from Monte Carlo simulations. The upper and lower interfaces of the liquid pool are tracked using a mesh structured with rotating spines. Experimental evaporation rates are obtained from measured feed rates, and heat flow rates are determined from measured temperature rises in the cooling water. The finite element model provides a good representation of the measured evaporation rates, heat flows, and lower pool boundary locations.

  8. Charge-state-dependent energy loss of slow ions. I. Experimental results on the transmission of highly charged ions

    NASA Astrophysics Data System (ADS)

    Wilhelm, Richard A.; Gruber, Elisabeth; Smejkal, Valerie; Facsko, Stefan; Aumayr, Friedrich

    2016-05-01

    We report on energy loss measurements of slow (v ≪v0 ), highly charged (Q >10 ) ions upon transmission through a 1-nm-thick carbon nanomembrane. We emphasize here the scaling of the energy loss with the velocity and charge exchange or loss. We show that a weak linear velocity dependence exists, whereas charge exchange dominates the kinetic energy loss, especially in the case of a large charge capture. A universal scaling of the energy loss with the charge exchange and velocity is found and discussed in this paper. A model for charge-state-dependent energy loss for slow ions is presented in paper II in this series [R. A. Wilhelm and W. Möller, Phys. Rev. A 93, 052709 (2016), 10.1103/PhysRevA.93.052709].

  9. Experimental Results in DIS from Jefferson Laboratory

    SciTech Connect

    Sebastian Kuhn

    2009-10-01

    We are summarizing the experimental program of Jefferson Lab (Thomas Jefferson National Accelerator Facility in Newport News, VA) in deep inelastic electron scattering. We show recent results and discuss future plans for both the present 6 GeV era and the 12 GeV energy-upgraded facility.

  10. Experimental results on evaporation waves

    NASA Astrophysics Data System (ADS)

    Grana Otero, Jose; Parra Fabian, Ignacio

    2010-11-01

    A liquid contained in a vertical glass tube is suddenly depressurized from a high initial pressure down to one for which the stable state is vapour, so vaporization sets off at the free surface. For large enough evaporation rates, the planar vapour-liquid interface is Darrieus-Landau unstable [1], leading to the interface surface rippling close to the instability threshold. Further increasing the initial to final pressure ratio brings about evaporation waves [2,3], in which a highly corrugated front propagates downwards into the liquid. A new experimental method is presented as well as some experimental results obtained by tracking the evolution of the front with a high speed camera. In addition, a number of new phenomena related to the dynamics of bubbles growth at the walls has been uncovered. In particular, a new mode of propagation of the evaporation front is found. In this mode the front originates from below the interface, so the propagation is upwards against gravity with a curved but smooth front.[4pt] [1] F. J. Higuera, Phys. Fluids, V. 30, 679 (1987).[0pt] [2] J.E.Shepherd and B.Sturtevant, J.Fluid Mech., V.121,379 (1982).[0pt] [3] P.Reinke and G.Yadigaroglu, Int.J.Multiph. Flow, V.27,1487 (2001).

  11. Experimental results from the small isochronous ring

    SciTech Connect

    Eduard Pozdeyev

    2005-05-01

    The Small Isochronous Ring (SIR) is a compact, low-energy storage ring designed to investigate the beam dynamics of high-intensity isochronous cyclotrons and synchrotrons at the transition energy. The ring was developed at Michigan State University (MSU) and has been operational since December 2003. It stores 20 keV hydrogen beams with a peak current of 10-20 microamps for up to 200 turns. The transverse and longitudinal profiles of extracted bunches are measured with an accuracy of approximately 1 mm. The high accuracy of the measurements makes the experimental data attractive for validation of multi-particle space charge codes. The results obtained in the ring show a fast growth of the energy spread induced by the space charge forces. The energy spread growth is accompanied by a breakup of the beam bunches into separated clusters that are involved in the vortex motion specific to the isochronous regime. The experimental results presented in the paper show a remarkable agreement with simulations performed with the code CYCO. In this paper, we discuss specifics of space charge effects in the isochronous regime, present results of experiments in SIR, and conduct a detailed comparison of the experimental data with results of simulations.

  12. Experimental simulation of radiation damage of polymers in space applications by cosmic-ray-type high energy heavy ions and the resulting changes in optical properties

    NASA Astrophysics Data System (ADS)

    Hossain, U. H.; Ensinger, W.

    2015-12-01

    Devices operating in space, e.g. in satellites, are being hit by cosmic rays. These include so-called HZE-ions, with High mass (Z) and energy (E). These highly energetic heavy ions penetrate deeply into the materials and deposit a large amount of energy, typically several keV per nm range. Serious damage is created. In space vehicles, polymers are used which are degraded under ion bombardment. HZE ion irradiation can experimentally be simulated in large scale accelerators. In the present study, the radiation damage of aliphatic vinyl- and fluoro-polymers by heavy ions with energies in the GeV range is described. The ions cause bond scission and create volatile small molecular species, leading to considerable mass loss of the polymers. Since hydrogen, oxygen and fluorine-containing molecules are created and these elements are depleted, the remaining material is carbon-richer than the original polymers and contains conjugated CC double bonds. This process is investigated by measuring the optical band gap with UV-Vis absorption spectrometry as a function of ion fluence. The results show how the optical band gaps shift from the UV into the Vis region upon ion irradiation for the different polymers.

  13. Synthesis of H2 in dirty ice mantles by fast ion energy loss: New experimental results increase the relevance of this mechanism

    NASA Technical Reports Server (NTRS)

    Pirranello, Valero; Brown, W. L.; Lanzerotti, L. J.; Averna, D. A.

    1989-01-01

    Recent experimental results support the importance of H2 production in molecular clouds by cosmic ray bombardment of the mantles of grains. The formation of molecules different from those originally present in the irradiated layer can be explained by the production of molecular fragments induced by the release of energy if the impinging fast particle. One way of considering the process is in terms of a transiently hot cylinder, initially about 50 A in diameter, that exists around the track of an individual fast ion. Since ice has a relatively low thermal conductivity, energy lost by the ion in the ice layers remains confined around the track for time long enough to be thermalized. The hot cylinder increases in diameter and decreases in temperature on a time scale of 10(exp -11) to 10(exp -10) sec. Molecular fragments that are formed in this high temperature region acquire enough mobility to recombine with different partners, forming new molecules. A Monte Carlo simulation of the interaction between cosmic rays and grain mantles, at various depths in the core of a spherical molecular cloud, was performed. The simulation was continued until 40,000 ions had hit each grain of the type and size chosen. During the performed experiments thin icy films made of H2O and CD4 mixed in the gas phase and deposited on a cold finger at 9 K were irradiated with 1.5 MeV helium beams. Among synthesized molecules were found H2, HD, and D2.

  14. Comparison between theoretical and experimental results for energy states of two-dimensional electron gas in pseudomorphically strained InAs high-electron-mobility transistors

    NASA Astrophysics Data System (ADS)

    Nishio, Yui; Tange, Takahiro; Hirayama, Naomi; Iida, Tsutomu; Takanashi, Yoshifumi

    2014-01-01

    The energy states of a two-dimensional electron gas (2DEG) in high-electron-mobility transistors with a pseudomorphically strained InAs channel (PHEMTs) were analyzed rigorously using a recently established theory that takes into account the nonparabolicity of the conduction band of the channel layer. The sheet density of the 2DEG in InxGa1-xAs-PHEMTs and the drain I-V characteristics of those devices were calculated theoretically and compared with the density and characteristics obtained experimentally. Not only the calculated threshold voltage (VTH) but also the calculated transconductance agreed fairly well with the corresponding values obtained experimentally. When the effects of the compositions of the InxGa1-xAs subchannel layer in the composite channel and the channel layer on energy states of 2DEG were investigated in order to establish a guiding principle for a design of the channel structure in PHEMTs, it was found that VTH is determined by the effective conduction-band offset energy ΔEC between the InAlAs barrier and the channel layers.

  15. Experimental Test Results of the Energy Efficient Transport (EET) Flap-Edge Vortex Model in the Langley Low-Turbulence Pressure Tunnel

    NASA Technical Reports Server (NTRS)

    Morgan, Harry L., Jr.

    2002-01-01

    This report presents the results of a test conducted in the Langley Low-Turbulence Pressure Tunnel to measure the flow field properties of a flap-edge vortex. The model was the EET (Energy Efficient Transport) Flap-Edge Vortex Model, which consists of a main element and a part-span, single-slotted trailing-edge flap. The model surface was instrumented with several chordwise and spanwise rows of pressure taps on each element. The off-body flow field velocities were to be measured in several planes perpendicular to the flap edge with a laser velocimetry system capable of measuring all three components in coincidence. However, due to seeding difficulties, the preliminary laser data did not have sufficient accuracy to be suitable for presentation; therefore, this report presents only the tabulated and plotted surface pressure data. In addition, the report contains a detail description of the model which can be used to generate accurate CFD grid structures.

  16. Experimental High Energy Physics Research

    SciTech Connect

    Hohlmann, Marcus

    2016-01-13

    This final report summarizes activities of the Florida Tech High Energy Physics group supported by DOE under grant #DE-SC0008024 during the period June 2012 – March 2015. We focused on one of the main HEP research thrusts at the Energy Frontier by participating in the CMS experiment. We were exploiting the tremendous physics opportunities at the Large Hadron Collider (LHC) and prepared for physics at its planned extension, the High-Luminosity LHC. The effort comprised a physics component with analysis of data from the first LHC run and contributions to the CMS Phase-2 upgrades in the muon endcap system (EMU) for the High-Luminosity LHC. The emphasis of our hardware work was the development of large-area Gas Electron Multipliers (GEMs) for the CMS forward muon upgrade. We built a production and testing site for such detectors at Florida Tech to complement future chamber production at CERN. The first full-scale CMS GE1/1 chamber prototype ever built outside of CERN was constructed at Florida Tech in summer 2013. We conducted two beam tests with GEM prototype chambers at CERN in 2012 and at FNAL in 2013 and reported the results at conferences and in publications. Principal Investigator Hohlmann served as chair of the collaboration board of the CMS GEM collaboration and as co-coordinator of the GEM detector working group. He edited and authored sections of the detector chapter of the Technical Design Report (TDR) for the GEM muon upgrade, which was approved by the LHCC and the CERN Research Board in 2015. During the course of the TDR approval process, the GEM project was also established as an official subsystem of the muon system by the CMS muon institution board. On the physics side, graduate student Kalakhety performed a Z' search in the dimuon channel with the 2011 and 2012 CMS datasets that utilized 20.6 fb⁻¹ of p-p collisions at √s = 8 TeV. For the dimuon channel alone, the 95% CL lower limits obtained on the mass of a Z' resonance are 2770 GeV for a Z

  17. Experimental High Energy Neutrino Astrophysics

    SciTech Connect

    Distefano, Carla

    2005-10-12

    Neutrinos are considered promising probes for high energy astrophysics. More than four decades after deep water Cerenkov technique was proposed to detect high energy neutrinos. Two detectors of this type are successfully taking data: BAIKAL and AMANDA. They have demonstrated the feasibility of the high energy neutrino detection and have set first constraints on TeV neutrino production astrophysical models. The quest for the construction of km3 size detectors have already started: in the South Pole, the IceCube neutrino telescope is under construction; the ANTARES, NEMO and NESTOR Collaborations are working towards the installation of a neutrino telescope in the Mediterranean Sea.

  18. Low-calorie sweetener use and energy balance: Results from experimental studies in animals, and large-scale prospective studies in humans.

    PubMed

    Fowler, Sharon P G

    2016-10-01

    For more than a decade, pioneering animal studies conducted by investigators at Purdue University have provided evidence to support a central thesis: that the uncoupling of sweet taste and caloric intake by low-calorie sweeteners (LCS) can disrupt an animal's ability to predict the metabolic consequences of sweet taste, and thereby impair the animal's ability to respond appropriately to sweet-tasting foods. These investigators' work has been replicated and extended internationally. There now exists a body of evidence, from a number of investigators, that animals chronically exposed to any of a range of LCSs - including saccharin, sucralose, acesulfame potassium, aspartame, or the combination of erythritol+aspartame - have exhibited one or more of the following conditions: increased food consumption, lower post-prandial thermogenesis, increased weight gain, greater percent body fat, decreased GLP-1 release during glucose tolerance testing, and significantly greater fasting glucose, glucose area under the curve during glucose tolerance testing, and hyperinsulinemia, compared with animals exposed to plain water or - in many cases - even to calorically-sweetened foods or liquids. Adverse impacts of LCS have appeared diminished in animals on dietary restriction, but were pronounced among males, animals genetically predisposed to obesity, and animals with diet-induced obesity. Impacts have been especially striking in animals on high-energy diets: diets high in fats and sugars, and diets which resemble a highly-processed 'Western' diet, including trans-fatty acids and monosodium glutamate. These studies have offered both support for, and biologically plausible mechanisms to explain, the results from a series of large-scale, long-term prospective observational studies conducted in humans, in which longitudinal increases in weight, abdominal adiposity, and incidence of overweight and obesity have been observed among study participants who reported using diet sodas and other

  19. Influence of Solid Target Reflectivity and Incident Angle on Depolarization Ratio and Reflected Energy from Polarized Lights: Experimental Results of the May 2008 Field Trial

    DTIC Science & Technology

    2009-11-01

    incident angle on depolarization ratio and reected energy from polarized lights is also provided. DRDC Valcartier TR 2008-394 i Résumé Des capteurs ...41.5 -22 10 Laiton Brass 10 -37.5 11 Aluminium Aluminum 26 -37.5 12 Acier "sand-blasté" Sandblasted steel 41.5 -37.5 13 Acier naturel Natural steel 10

  20. Summary of recent experimental results on strangeness production

    NASA Astrophysics Data System (ADS)

    Kalweit, Alexander

    2017-01-01

    This article summarises the highlights of the recent experimental findings on strangeness production presented at the 16th edition of the International Conference on Strangeness in Quark Matter in Berkeley. Results obtained by eight large experimental collaborations (ALICE, ATLAS, CMS, HADES, LHCb, NA-61, PHENIX, STAR) spanning a large range in centre-of-mass energy and a variety of collision systems were presented at the conference. The article does not aim at being a complete review, but rather at connecting the experimental highlights of the different collaborations and at pointing towards questions which should be addressed by these experiments in future.

  1. Fuel-rich, catalytic reaction experimental results

    NASA Technical Reports Server (NTRS)

    Rollbuhler, R. James

    1991-01-01

    Future aeropropulsion gas turbine combustion requirements call for operating at very high inlet temperatures, pressures, and large temperature rises. At the same time, the combustion process is to have minimum pollution effects on the environment. Aircraft gas turbine engines utilize liquid hydrocarbon fuels which are difficult to uniformly atomize and mix with combustion air. An approach for minimizing fuel related problems is to transform the liquid fuel into gaseous form prior to the completion of the combustion process. Experimentally obtained results are presented for vaporizing and partially oxidizing a liquid hydrocarbon fuel into burnable gaseous components. The presented experimental data show that 1200 to 1300 K reaction product gas, rich in hydrogen, carbon monoxide, and light-end hydrocarbons, is formed when flowing 0.3 to 0.6 fuel to air mixes through a catalyst reactor. The reaction temperatures are kept low enough that nitrogen oxides and carbon particles (soot) do not form. Results are reported for tests using different catalyst types and configurations, mass flowrates, input temperatures, and fuel to air ratios.

  2. Overview of the Initial NSTX Experimental Results

    SciTech Connect

    M. Ono; M. Bell; R. E. Bell; T. Bigelow; M. Bitter; et al

    2000-11-16

    The main aim of the National Spherical Torus Experiment (NSTX) is to establish the fusion physics principles of the spherical torus (ST) concept. The NSTX device began plasma operations in February 1999 and the plasma current Ip was successfully brought up to the design value of 1 million amperes on December 14, 1999. The planned plasma shaping parameters, k = 1.6 {+-} 2.2 and d = 0.2 {+-} 0.4, were achieved in inner limited, single null and double null configurations. The CHI (Coaxial Helicity Injection) and HHFW (High Harmonic Fast Wave) experiments were also initiated. A CHI injected current of 27 kA produced up to 260 kA of toroidal current without using an ohmic solenoid. With an injection of 2.3 MW of HHFW power, using twelve antennas connected to six transmitters, electrons were heated from a central temperature of 400 eV to 900 eV at a centraldensity of 3.5 x 1013 cm-3 increasing the plasma energy to 59 kJ and the toroidal beta, bT to 10 %. Finally, the NBI system commenced operatio n in Sept. 2000. The initial results with two ion sources (PNBI = 2.8 MW) shows good heating, producing a total plasma stored energy of 90 kJ corresponding to bT = 18 % at a plasma current of 1.1 MA

  3. Testing Numerical Dynamo Models Against Experimental Results

    NASA Astrophysics Data System (ADS)

    Gissinger, C. J.; Fauve, S.; Dormy, E.

    2007-12-01

    Significant progress has been achieved over the past few years in describing the geomagnetic field using computer models for dynamo action. Such models are so far limited to parameter regimes which are very remote from actual values relevant to the Earth core or any liquid metal (the magnetic Prandtl number is always over estimated by a factor at least 104). While existing models successfully reproduce many of the magnetic observations, it is difficult to assert their validity. The recent success of an experimental homogeneous unconstrained dynamo (VKS) provides a new way to investigate dynamo action in turbulent conducting flows, but it also offers a chance to test the validity of exisiting numerical models. We use a code originaly written for the Geodynamo (Parody) and apply it to the experimental configuration. The direct comparison of simulations and experiments is of great interest to test the predictive value of numerical simulations for dynamo action. These turbulent simulations allow us to approach issues which are very relevant for geophysical dynamos, especially the competition between different magnetic modes and the dynamics of reversals.

  4. Selected experimental results from heavy-ion collisions at LHC

    DOE PAGES

    Singh, Ranbir; Kumar, Lokesh; Netrakanti, Pawan Kumar; ...

    2013-01-01

    We reviewmore » a subset of experimental results from the heavy-ion collisions at the Large Hadron Collider (LHC) facility at CERN. Excellent consistency is observed across all the experiments at the LHC (at center of mass energysNN=2.76 TeV) for the measurements such as charged particle multiplicity density, azimuthal anisotropy coefficients, and nuclear modification factor of charged hadrons. Comparison to similar measurements from the Relativistic Heavy Ion Collider (RHIC) at lower energy (sNN=200 GeV) suggests that the system formed at LHC has a higher energy density and larger system size and lives for a longer time. These measurements are compared to model calculations to obtain physical insights on the properties of matter created at the RHIC and LHC.« less

  5. Experimental results on chiral magnetic and vortical effects

    DOE PAGES

    Wang, Gang; Wen, Liwen

    2017-01-12

    Various novel transport phenomena in chiral systems result from the interplay of quantum anomalies with magnetic field and vorticity in high-energy heavy-ion collisions and could survive the expansion of the fireball and be detected in experiments. Among them are the chiral magnetic effect, the chiral vortical effect, and the chiral magnetic wave, the experimental searches for which have aroused extensive interest. As a result, the goal of this review is to describe the current status of experimental studies at Relativistic Heavy-Ion Collider at BNL and the Large Hadron Collider at CERN and to outline the future work in experiment neededmore » to eliminate the existing uncertainties in the interpretation of the data.« less

  6. Experimental rotordynamic coefficient results for honeycomb seals

    NASA Technical Reports Server (NTRS)

    Elrod, David A.; Childs, Dara W.

    1988-01-01

    Test results (leakage and rotordynamic coefficients) are presented for seven honeycomb-stator smooth-rotor seals. Tests were carried out with air at rotor speeds up to 16,000 cpm and supply pressures up to 8.2 bars. Test results for the seven seals are compared, and the most stable configuration is identified based on the whirl frequency ratio. Results from tests of a smooth-rotor/smooth-stator seal, a teeth-on-stator labyrinth seal, and the most stable honeycomb seal are compared.

  7. Adaptive structures - Test hardware and experimental results

    NASA Technical Reports Server (NTRS)

    Wada, Ben K.; Fanson, James L.; Chen, Gun-Shing; Kuo, Chin-Po

    1990-01-01

    The facilities and procedures used at JPL to test adaptive structures such as the large deployable reflector (LDR) are described and preliminary results are reported. The applications of adaptive structures in future NASA missions are outlined, and the techniques which are employed to modify damping, stiffness, and isolation characteristics, as well as geometric changes, are listed. The development of adaptive structures is shown to be effective as a result of new actuators and sensors, and examples are listed for categories such as fiber optics, shape-memory materials, piezoelectrics, and electrorheological fluids. Some ground test results are described for laboratory truss structures and truss test beds, which are shown to be efficient and easy to assemble in space. Adaptive structures are shown to be important for precision space structures such as the LDR, and can alleviate ground test requirements.

  8. The Humanoid Robot LOLA—Experimental Results

    NASA Astrophysics Data System (ADS)

    Favot, V.; Schwienbacher, M.; Buschmann, T.; Lohmeier, S.; Ulbrich, H.

    2010-09-01

    With the experience gathered during the development and construnction of the robot JOHNNIE, a new humanoid robot LOLA was built. Goal of this project is to realize a fast, human-like walking. Different aspects of this complex mechatronic system and the first experiments results are presented. The lightweight construction and the custom build multi-sensory joint drives with high torque brushless motors are introduced. The new decentralized electronic control/sensing network is also discuss as well as the simulation environment, the trajectory planning algorithm and the stabilizing walking control. Finally the first experiments result are presented.

  9. Tracer Developments: Results of Experimental Studies

    SciTech Connect

    Adams, M.C.; Ahn, J.H.; Bentley, H.; Moore, J.N.; Veggeberg, S.

    1986-01-21

    Tracers can be used to monitor the movement of groundwaters and geothermal fluids and they can be used as a reference to quantify changes in fluid chemistry as a result of injection. Despite their potential importance to the geothermal operator, very few tracers are presently available and of those that are, little is known about their stability or behavior at the elevated temperatures that typify resources capable of electric power generation. During the past two years the University of Utah Research Institute has been involved in tracer research and testing, largely through the DOE Injection Research Program. The purpose of this paper is to summarize the results of these laboratory and field investigations.

  10. Numerical taxonomy on data: Experimental results

    SciTech Connect

    Cohen, J.; Farach, M.

    1997-12-01

    The numerical taxonomy problems associated with most of the optimization criteria described above are NP - hard [3, 5, 1, 4]. In, the first positive result for numerical taxonomy was presented. They showed that if e is the distance to the closest tree metric under the L{sub {infinity}} norm. i.e., e = min{sub T} [L{sub {infinity}} (T-D)], then it is possible to construct a tree T such that L{sub {infinity}} (T-D) {le} 3e, that is, they gave a 3-approximation algorithm for this problem. We will refer to this algorithm as the Single Pivot (SP) heuristic.

  11. On collisional disruption - Experimental results and scaling laws

    NASA Technical Reports Server (NTRS)

    Davis, Donald R.; Ryan, Eileen V.

    1990-01-01

    Both homogeneous and inhomogeneous targets have been addressed by the present experimental consideration of the impact strengths, fragment sizes, and fragment velocities generated by cement mortar targets whose crushing strengths vary by an order of magnitude, upon impact of projectiles in the velocity range of 50-5700 m/sec. When combined with additional published data, dynamic impact strength is found to correlate with quasi-static material strengths for materials ranging in character from basalt to ice; two materials not following this trend, however, are weak mortar and clay targets. Values consistent with experimental results are obtainable with a simple scaling algorithm based on impact energy, material properties, and collisional strain rate.

  12. Experimental results on diffraction at CDF

    SciTech Connect

    Gallinaro, Michele; /Rockefeller U. /Lisbon, LIFEP

    2010-09-01

    Diffractive events are studied by means of identification of one or more rapidity gaps and/or a leading antiproton. Measurements of soft and hard diffractive processes have been performed at the Tevatron p{bar p} collider and presented. We report on the diffractive structure function obtained from dijet production in the range 0 < Q{sup 2} < 10,000 GeV{sup 2}, and on the |t| distribution in the region 0 < |t| < 1 GeV{sup 2} for both soft and hard diffractive events up to Q{sup 2} {approx} 4,500 GeV{sup 2}. Results on single diffractive W/Z production, forward jets, and central exclusive production of both dijets and Z-bosons are also presented.

  13. Ventricular Fibrillation in Mammalian Hearts: Experimental Results

    NASA Astrophysics Data System (ADS)

    Gray, Richard A.

    2002-03-01

    Ventricular fibrillation (VF) is sustained by the continuous “breakup” of rapidly rotating spiral waves. The rate dependence of action potential duration (APD), i.e. APD restitution, plays a role in the induction and breakup of spiral waves. However, the role of conduction velocity (CV) and spatial heterogeneities, in VF induction and maintenance is not clear. We studied restitution, its spatial dispersion, and VF in small (rabbit) and large (pig) hearts using a video imaging system. We studied the effect of two drugs, diacetyl monoxime (DAM) and cytochalasinD (Cyto), in rabbit hearts. Control APDs were shorter than for Cyto but longer than for DAM. CV was greater for Cyto compared to DAM and APD dispersion increased with increasing rate for both drugs. VF was sustained in control, non-sustained with CytoD, and converted to a stable reentry (VT) with DAM. The slight increase of APD with Cyto increased the wavelength and probably prevented VF from being sustained. The DAM results can be explained by the reduction of wavelength and slope of the APD restitution curve. Except for VF, CytoD results were similar to controls. We performed similar studies in larger (pig) hearts with Cyto. APD and restitution slope at rapid rates were smaller for the pig compared to the rabbit. In the pig, APDs recorded during pacing induction protocols, VF and VT demonstrated that during periods of transition, APDs did not fall on the restitution curve. However, the deviations were predictable. During rapid pacing and VT/VF induction, APDs were longer than predicted from the restitution curve, while they were shorter for the conversions of VF to VT and their terminations. Overall, these studies are beginning to elucidate the dynamics and factors involved in the complex spatio-temporal patterns and their transitions that occur at rapid rates such as VT and VF.

  14. Inviscid Flow Field Effects: Experimental results

    NASA Astrophysics Data System (ADS)

    Otten, L. J., III; Gilbert, K. G.

    1980-04-01

    The aero-optical distortions due to invisid flow effects over airborne laser turrets is investigated. Optical path differences across laser turret apertures are estimated from two data sources. The first is a theoretical study of main flow effects for a spherical turret assembly for a Mach number (M) of 0.6. The second source is an actual wind tunnel density field measurement on a 0.3 scale laser turret/fairing assembly, with M = 0.75. A range of azimuthal angles from 0 to 90 deg was considered, while the elevation angle was always 0 deg (i.e., in the plane of the flow). The calculated optical path differences for these two markedly different geometries are of the same order. Scaling of results to sea level conditions and an aperture diameter of 50 cm indicated up to 0.0007 cm of phase variation across the aperture for certain forward look angles and a focal length of F = -11.1 km. These values are second order for a 10.6 micron system.

  15. [Experimental and theoretical high energy physics program

    SciTech Connect

    Finley, J.; Gaidos, J.A.; Loeffler, F.J.; McIlwain, R.L.; Miller, D.H.; Palfrey, T.R.; Shibata, E.I.; Shipsey, I.P.

    1993-04-01

    Experimental and theoretical high-energy physics research at Purdue is summarized in a number of reports. Subjects treated include the following: the CLEO experiment for the study of heavy flavor physics; gas microstrip detectors; particle astrophysics; affine Kac{endash}Moody algebra; nonperturbative mass bounds on scalar and fermion systems due to triviality and vacuum stability constraints; resonance neutrino oscillations; e{sup +}e{sup {minus}} collisions at CERN; {bar p}{endash}p collisions at FNAL; accelerator physics at Fermilab; development work for the SDC detector at SSC; TOPAZ; D-zero physics; physics beyond the standard model; and the Collider Detector at Fermilab. (RWR)

  16. Theoretical and Experimental Results Regarding LENR/CF

    SciTech Connect

    Robert W. Bass; Wm. Stan Gleeson

    2000-11-12

    We challenge the predominant view that low-energy nuclear reactions (LENRs) are prohibited by standard quantum mechanics (QM). This view, supposedly based on standard nuclear theory, need not apply in condensed-matter environments. These considerations indicate that seemingly novel experimental evidence of rapid aneutronic bulk-process transmutation, at extraordinarily low-energy levels, in a simple electrochemical reactor, can occur. This explains: (a) induced rapid decay of radioactive thorium into stable nuclides, e.g., Cu and (b) resulting, anomalous distribution of Cu isotopes. We reexamine arguments of Peebles cited as evidence that standard QM 'forbids' cold fusion (CF). We note oversimplifications in those and present an alternative, more sophisticated calculation (see Bass, Refs. 3 through 8) demonstrating that conventional wisdom about impenetrability of the 'Coulomb barrier' fails as a result of periodic-order-induced resonance. We also examine empirical evidence. In three independent tests of an LENR electrolysis cell, using different I-V-T (current/voltage/time) protocols, the percentage of radiation reduction (RR) transmutation achieved {eta}=[23{percent}, 50{percent}, 83{percent}] versus expended energy E=[0.6535, 32.5, 74.6] (Watt-hours), obtained by numerical integration of recorded product I{center_dot}V for processing time T, provides near-perfect straight-line correlation: {eta}={alpha}{center_dot}E + {eta}{sub 0}, {alpha}=0.8105, {eta}{sub 0}=22.888, (0.65 < E < 0.75).

  17. Microscopic cluster model for the description of new experimental results on the 13C(18O,16O) 15C two-neutron transfer at 84 MeV incident energy

    NASA Astrophysics Data System (ADS)

    Carbone, D.; Ferreira, J. L.; Cappuzzello, F.; Lubian, J.; Agodi, C.; Cavallaro, M.; Foti, A.; Gargano, A.; Lenzi, S. M.; Linares, R.; Santagati, G.

    2017-03-01

    The 13C(18O,16O) 15C reaction is studied at 84 MeV incident energy. Excitation energy spectra and absolute cross-section angular distributions for the strongest transitions are measured with good energy and angular resolutions. Strong selectivity for two-neutron configurations in the states of the residual nucleus is found. The measured cross-section angular distributions are analyzed by exact finite-range coupled reaction channel calculations. The two-particle wave functions are extracted using the extreme cluster and the independent coordinate scheme with shell-model derived coupling strengths. A new approach also is introduced, the microscopic cluster, in which the spectroscopic amplitudes in the center-of-mass reference frame are derived from shell-model calculations using the Moshinsky transformation brackets. This new model is able to describe well the experimental cross section and to highlight cluster configurations in the involved wave functions.

  18. Experimental Results of Hydrate Reservoir Destabilization Through Heating

    NASA Astrophysics Data System (ADS)

    Leeman, J.; Hornbach, M. J.; Elwood-Madden, M.; Phelps, T. J.; Rawn, C. J.

    2011-12-01

    Gas clathrate reservoirs have been considered as possible sources of energy, as hazards to deep water drilling operations, and as contributors to global climate change. Clathrate destabilization may occur through depressurization of the reservoir, addition of chemical inhibitors, or heating the reservoir. Meso-scale heat conduction experiments were conducted in the Seafloor Process Simulator (SPS) at Oak Ridge National Laboratory in an attempt to apply experimental constraints to purely numerical models of heat transfer within a nearly isobaric reservoir. A column of saturated sediment was place inside the pressure vessel and pressurized to conditions sufficient to form methane clathrate at seafloor temperatures, while the system remained at room temperature (298K). Once pressurized, the temperature of the vessel was then lowered to approximately 275K, forming pore filling clathrate in the sediment column. Following hydrate formation, heat was supplied to the center of the clathrate reservoir through a hot fluid heat exchanger embedded in the sediment column to dissociate the methane hydrate. Relative changes in temperature within the hydrate-sediment column were monitored with a fiber optic quasi-distributed sensing system (DSS), along with temperature and pressure within the vessel headspace. Using the DSS Plotter analysis software, it was determined that an axis-symmetric section of clathrate was dissociated around the heat exchanger. Clathrate dissociation was accompanied by a small rise in vessel headspace pressure in addition to the expected thermal expansion of the headspace gas. The quantity of heat input to the system was calculated from the drop in fluid temperature as it flowed through the heat exchanger. Increased heat input resulted in an increase in the volume of hydrate dissociated. Clathrate rapidly reformed immediately upon the removal of the heat energy. A simple numerical model has been developed to simulate the heat flow in the system. Early

  19. Experimental feature in the primary-proton flux at energies above 10 TeV according to the results of searches for primary particles in nuclear emulsions exposed in the stratosphere (RUNJOB Experiment)

    SciTech Connect

    Zayarnaya, I. S.

    2008-02-15

    In the RUNJOB experiment, a long-term exposure of x-ray emulsion chambers in the stratosphere from 1995 to 1999 with the aim of studying the composition and spectra of primary cosmic particles in the energy range 10-1000 TeV per nucleon revealed about 50% proton tracks. The remaining events of the proton group did not feature any candidate for a track of a singly charged particle within the search region determined from measurements of the coordinates of background nuclei going close to the sought track. Methodological factors that could explain this experimental observation are considered. A possible physical reason associated with the presence of a neutral component in the flux of primary protons in the energy region above 10 TeV is also analyzed.

  20. Non-shock initiation model for explosive families : experimental results.

    SciTech Connect

    Anderson, Mark U.; Jensen, Charles B.; Todd, Steven N.; Hugh, Chance G.; Caipen, Terry L.

    2010-03-01

    The 'DaMaGe-Initiated-Reaction' (DMGIR) computational model has been developed to predict the response of high explosives to non-shock mechanical insults. The distinguishing feature of this model is the introduction of a damage variable, which relates the evolution of damage to the initiation of a reaction in the explosive, and its growth to detonation. Specifically designed experiments were used to study the initiation process of each explosive family with embedded shock sensors and optical diagnostics. The experimental portion of this model development began with a study of PBXN-5 to develop DMGIR model coefficients for the rigid plastic bonded family, followed by studies of the cast, and bulk-moldable explosive families. The experimental results show an initiation mechanism that is related to input energy and material damage, with well defined initiation thresholds for each explosive family. These initiation details will extend the predictive capability of the DMGIR model from the rigid family into the cast and bulk-moldable families.

  1. Acoustic analysis in Mudejar-Gothic churches: Experimental results

    NASA Astrophysics Data System (ADS)

    Galindo, Miguel; Zamarreño, Teófilo; Girón, Sara

    2005-05-01

    This paper describes the preliminary results of research work in acoustics, conducted in a set of 12 Mudejar-Gothic churches in the city of Seville in the south of Spain. Despite common architectural style, the churches feature individual characteristics and have volumes ranging from 3947 to 10 708 m3. Acoustic parameters were measured in unoccupied churches according to the ISO-3382 standard. An extensive experimental study was carried out using impulse response analysis through a maximum length sequence measurement system in each church. It covered aspects such as reverberation (reverberation times, early decay times), distribution of sound levels (sound strength); early to late sound energy parameters derived from the impulse responses (center time, clarity for speech, clarity, definition, lateral energy fraction), and speech intelligibility (rapid speech transmission index), which all take both spectral and spatial distribution into account. Background noise was also measured to obtain the NR indices. The study describes the acoustic field inside each temple and establishes a discussion for each one of the acoustic descriptors mentioned by using the theoretical models available and the principles of architectural acoustics. Analysis of the quality of the spaces for music and speech is carried out according to the most widespread criteria for auditoria. .

  2. Acoustic analysis in Mudejar-Gothic churches: experimental results.

    PubMed

    Galindo, Miguel; Zamarreño, Teófilo; Girón, Sara

    2005-05-01

    This paper describes the preliminary results of research work in acoustics, conducted in a set of 12 Mudejar-Gothic churches in the city of Seville in the south of Spain. Despite common architectural style, the churches feature individual characteristics and have volumes ranging from 3947 to 10 708 m3. Acoustic parameters were measured in unoccupied churches according to the ISO-3382 standard. An extensive experimental study was carried out using impulse response analysis through a maximum length sequence measurement system in each church. It covered aspects such as reverberation (reverberation times, early decay times), distribution of sound levels (sound strength); early to late sound energy parameters derived from the impulse responses (center time, clarity for speech, clarity, definition, lateral energy fraction), and speech intelligibility (rapid speech transmission index), which all take both spectral and spatial distribution into account. Background noise was also measured to obtain the NR indices. The study describes the acoustic field inside each temple and establishes a discussion for each one of the acoustic descriptors mentioned by using the theoretical models available and the principles of architectural acoustics. Analysis of the quality of the spaces for music and speech is carried out according to the most widespread criteria for auditoria.

  3. Results of NASA's Energy Efficient Engine Program

    NASA Technical Reports Server (NTRS)

    Ciepluch, Carl C.; Davis, Donald Y.; Gray, David E.

    1987-01-01

    The major activity undertaken in the NASA Energy Efficient Engine Program has been completed. This paper reports on the progress made toward achieving the program goal of developing advanced technology to significantly reduce fuel consumption and operating costs of future subsonic transport-type propulsion systems. An additional goal was that the advanced concepts be compatible with future environmental regulations. Along with the results obtained, a brief overview of the design details of both the General Electric and Pratt and Whitney energy efficient engines and the overall program scope are presented. Overall, this program has been highly successful; the technology developed during its course is, and will continue to be, effectively employed in both current and future advance transport aircraft engine designs.

  4. Experimental Results on Jets in pA

    NASA Astrophysics Data System (ADS)

    Appelt, Eric

    2015-04-01

    The experimentally observed reduction of jet yields in ultrarelativistic heavy ion (AA) collisions relative to proton-proton (pp) collisions is widely interpreted in terms of energy loss of a hard scattered parton traversing a quark-gluon plasma (QGP) before fragmenting into a jet of hadrons. In order to constrain proposed mechanisms of energy loss, a variety of measurements are needed that quantify both how the jet yields and jet structure are modified in the medium. However, jets may also be modified by differences in the initial state of the nucleus relative to that of the proton. The precise determination of the QGP properties relies on disentangling these additional modifications, collectively termed ``cold nuclear matter'' effects, from energy loss in the QGP. Collisions between heavy ions and protons (pA) provide a potential control environment where cold nuclear matter effects should be present, but QGP formation is generally not expected to occur. In this talk, an overview of recent jet results from proton-lead collisions produced at the LHC will be given. The yield of inclusive jets and distributions of dijet pairs are shown to be compatible with generally accepted theoretical expectations, although significant modification is observed when yields are measured from specific centrality classes of pA collision events. Some measurements of high-pT charged hadron yields suggest a larger modification in pA collisions relative to pp collisions than for inclusive jet yields. The potential implications of this difference along with other measurements relating to jet structure will be discussed.

  5. Methods of experimentation with models and utilization of results

    NASA Technical Reports Server (NTRS)

    Robert,

    1924-01-01

    The present report treats the subject of testing small models in a wind tunnel and of the methods employed for rendering the results constant, accurate and comparable with one another. Detailed experimental results are given.

  6. Experimental evaluation of a cruciform piezoelectric energy harvester

    NASA Astrophysics Data System (ADS)

    Tsuruta, Karina M.; Rade, Domingos A.; Finzi Neto, Roberto M.; Cavalini, Aldemir A.

    2016-10-01

    This paper describes the development and experimental evaluation of a particular type of piezoelectric energy harvester, composed of four aluminum cantilever blades to which piezoelectric patches are bonded, in such way that electric energy is generated when the blades undergo bending vibrations. Concentrated masses, whose values can be varied, are attached to the tips of the blades. Due to the geometric shape of the harvester, in which the four blades are oriented forming right angles, the harvester is named cruciform. As opposed to the large majority of previous works on the subject, in which harvesters are excited at their bases by prescribed acceleration, herein the harvester is connected to a vibrating structure excited by an imbalance force. Hence, the amount of harvested energy depends upon the dynamic interaction between the harvester and the host structure. Laboratory experiments were carried-out on a prototype connected to a tridimensional truss. The experimental setup includes a force generator consisting of an imbalanced disc driven by an electrical motor whose rotation is controlled electronically, a voltage rectifier circuit, and a battery charged with the harvested energy. After characterization of the dynamic behavior of the harvester and the host structure, both numerically and experimentally, the results of experiments are presented and discussed in terms of the voltage output of the piezoelectric transducers as function of the excitation frequency and the values of the tip masses. Also, the capacity of the harvester to charge a Lithium battery is evaluated.

  7. Experimental results on atomic oxygen corrosion of silver

    NASA Technical Reports Server (NTRS)

    Fromhold, Albert T.

    1988-01-01

    The results of an experimental study of the reaction kinetics of silver with atomic oxygen in 10 degree increments over the temperature range of 0 to 70 C is reported. The silver specimens, of the order of 10,000 A in thickness, were prepared by thermal evaporation onto 3 inch diameter polished silicon wafers. There were later sliced into pieces having surface areas of the order of 1/4 to 1/2 square inch. Atomic oxygen was generated by a gas discharge in a commercial plasmod asher operating in the megahertz frequency range. The sample temperature within the chamber was controlled by means of a thermoelectric unit. Exposure of the silver specimens to atomic oxygen was incremental, with oxide film thickness measurements being carried out between exposures by means of an automated ellipsometer. For the early growth phase, the data can be described satisfactorily by a logarithmic growth law: the oxide film thickness increases as the logarithm of the exposure time. Furthermore, the oxidation process is thermally activated, the rate increasing with increasing temperature. However, the empirical activation energy parameter deduced from Arrhenius plots is quite low, being of the order of 0.1 eV.

  8. Ground coupled heat-pump-system experimental results

    NASA Astrophysics Data System (ADS)

    Metz, P. D.

    1983-06-01

    Since October 1980, a small house in Upton, Long Island, New York has been heated and cooled by a liquid source heat pump using a shallow serpentine earth coil as a heat source/sink. After a brief introduction and system description, system performance data are presented, for the winter of 1981-82 and the summer of 1982, followed by a discussion of these results. The experimental test house is a 104 m(2) (1120 ft(2)) 3 bedroom ranch of energy saving construction with a heating load of 7.8 x 10 to the 6th power J/0C-day (4.1 x 10 to the 3rd power Btu/0F-day). The heat pump used during most of the period reported on here is a commercially available water to air unit sized to just meet the building design heating load with no auxiliary heat. The earth coil contains 155 m (507 ft) of nominal 1-1/2 in. medium density polyethylene pipe, and is approximately 25% ethylene glycol in water, is employed to permit subfreezing earth coil operation. Two independent data acquisition systems, a datalogger microcomputer system backed up by a Btu meter, monitor the space conditioning system performance.

  9. A new direct infrared laser absorption method for state-to-state rotational energy transfer in crossed supersonic jets: Experimental results and quantum scattering analysis for Ar+CH4

    NASA Astrophysics Data System (ADS)

    Nesbitt, David J.; Nibler, Joseph W.; Schiffman, Aram; Chapman, William B.; Hutson, Jeremy M.

    1993-06-01

    A new method for measuring state-to-state rotational energy transfer in crossed supersonic beams is described. The method is based on direct absorption of tunable, high-resolution infrared laser light by target molecules collisionally excited into final rotational states. The direct IR absorption approach offers high sensitivity, full quantum state resolution, a Doppler probe of final velocity components, and is applicable to any target molecule that absorbs in the near IR. Preliminary results are presented for Ar+CH4 scattering in crossed supersonic beams at a mean center-of-mass collision energy of 41 meV. Because of the high spectral resolution, the method can readily distinguish rotational fine structure states of A, F, and E symmetry in the tetrahedral group, as well as the much more energetically separated final j states. The results are compared with full quantum close-coupling calculations on two different Ar+CH4 potential energy surfaces. The state-to-state scattering results provide a sensitive measure of the potential anisotropy, and in particular probe the relative magnitudes of the different anisotropic terms in the potential (V3 and V4).

  10. Numerical and experimental design of coaxial shallow geothermal energy systems

    NASA Astrophysics Data System (ADS)

    Raghavan, Niranjan

    Geothermal Energy has emerged as one of the front runners in the energy race because of its performance efficiency, abundance and production competitiveness. Today, geothermal energy is used in many regions of the world as a sustainable solution for decreasing dependence on fossil fuels and reducing health hazards. However, projects related to geothermal energy have not received their deserved recognition due to lack of computational tools associated with them and economic misconceptions related to their installation and functioning. This research focuses on numerical and experimental system design analysis of vertical shallow geothermal energy systems. The driving force is the temperature difference between a finite depth beneath the earth and its surface stimulates continuous exchange of thermal energy from sub-surface to the surface (a geothermal gradient is set up). This heat gradient is captured by the circulating refrigerant and thus, tapping the geothermal energy from shallow depths. Traditionally, U-bend systems, which consist of two one-inch pipes with a U-bend connector at the bottom, have been widely used in geothermal applications. Alternative systems include coaxial pipes (pipe-in-pipe) that are the main focus of this research. It has been studied that coaxial pipes have significantly higher thermal performance characteristics than U-bend pipes, with comparative production and installation costs. This makes them a viable design upgrade to the traditional piping systems. Analytical and numerical heat transfer analysis of the coaxial system is carried out with the help of ABAQUS software. It is tested by varying independent parameters such as materials, soil conditions and effect of thermal contact conductance on heat transfer characteristics. With the above information, this research aims at formulating a preliminary theoretical design setup for an experimental study to quantify and compare the heat transfer characteristics of U-bend and coaxial

  11. Relativistic effect on total energies for determination of correlation energies of atoms from their experimental total energies

    NASA Astrophysics Data System (ADS)

    Anno, Tosinobu; Teruya, Hirohide

    1989-10-01

    Relativistic effect Erel upon the total electronic energy of an atom is discussed with particular reference to obtaining the nonrelativistic total energy Eexact from the experimental total energy. Numerical values of this effect obtained by various authors by different nonempirical methods are compared for neutral atoms of rare-gas elements. It is shown that methods either of a Hartree-Fock-type or of a Dirac-Hartree-Fock-type give much the same Erel value for He through Ar. It is pointed out that Erel calculated with Hartree-Fock wave functions is not adequate for use in obtaining Eexact from the experimental total energy and that the Erel value calculated with wave functions including electron correlation should work well, although an actual demonstration can be done only for two-electron systems for lack of data. A semiempirical formula is therefore proposed, which is useful for least-squares fit of experimental total energies of isoelectronic series of atoms to extract nonrelativistic total energies along with the relativistic effect. From nonrelativistic energies thus derived, semiempirical values of correlation energies of atoms are obtained. The results thus obtained are in reasonable agreement with correlation energies derived by Clementi along somewhat different lines. The power series expansion in Z of the fitted formula for the He series shows that numerical values of expansion coefficients agree reasonably well with the corresponding values obtained by accurate relativistic and nonrelativistic Z expansion-type calculations.

  12. Numerical and experimental studies of liquid storage tank thermal stratification for a solar energy system

    SciTech Connect

    Wu, S T; Han, S M

    1980-11-01

    The results of theoretical and experimental studies of thermal stratification in liquid energy storage tanks for the performance of solar energy systems are presented. The investigation was divided into three areas: (1) Justification of the Importance of Thermal Stratification Inside the Energy Storage Tanks, (II) Development of a Simple Mathematical Model which is Compatible with Existing Solar Energy System Simulation Code, and (III) Validation of Mathematical Models by Experimental Data Obtained from Realistic Solar Energy System Operations.

  13. Energy Monitoring in Gins - 2012 Preliminary Results

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Electricity and fuel are the second largest source of variable costs for cotton gins, after labor. Few studies of gin energy use have been conducted recently and none have monitored energy use continuously throughout the ginning season. More detailed information is needed to identify management st...

  14. Experimental study of energy conversion in the magnetic reconnection layer

    NASA Astrophysics Data System (ADS)

    Yamada, Masaaki

    2014-10-01

    Magnetic reconnection, in which magnetic field lines break and reconnect to change their topology, occurs throughout the universe: in solar flares, the earth's magnetosphere, star forming galaxies, and laboratory fusion plasmas. The essential feature of reconnection is that it energizes plasma particles by converting magnetic energy to particle energy; this process both accelerates and heats the plasma particles. Despite the recent advances of reconnection research, the exact mechanisms for bulk plasma heating, particle acceleration, and energy flow channels remain unresolved. In this work, the mechanisms responsible for the energization of plasma particles in the magnetic reconnection layer are investigated in the MRX device together with a quantitative evaluation of the conversion of magnetic energy to ions and electrons. A comprehensive analysis of the reconnection layer is made in terms of two-fluid physics based on the measurements of two-dimensional profiles of 1) electric potential, 2) flow vectors of electrons and ions, and 3) the electron temperature, Te and the ion temperature, Ti in the layer. It is experimentally verified that a saddle shaped electrostatic electric potential profile is formed in the reconnection plane. Ions are accelerated across the separatrices by the strong electrostatic field and enter the exhaust region where they become thermalized. Electron heating is observed to extend beyond the electron diffusion region, and non-classical heating mechanisms associated with high frequency fluctuations is found to play a role. Our quantitative analysis of the energy transport processes and energy inventory concludes that more than 50% of magnetic energy is converted to plasma particles, of which 2/3 transferred to ions and 1/3 to electrons. The results which demonstrate that conversion of magnetic energy occurs in a significantly larger region than theoretically considered before, are compared with the two-fluid simulations and the recent space

  15. Experimental Results for an Annular Aerospike with Differential Throttling

    NASA Technical Reports Server (NTRS)

    Ruf, Joseph H.; McDaniels, David M.

    2003-01-01

    Marshall Space Flight Center funded an internal study on Altitude Compensating Nozzles (ACN) for aerospike engines. The experimental hardware for the engine test is described in this viewgraph presentation, as well as the results of the experiment. The results include spike wall pressures, nozzle efficiency, and side force for four nozzle configurations.

  16. Energy: Machines, Science (Experimental): 5311.03.

    ERIC Educational Resources Information Center

    Castaldi, June P.

    This unit of instruction was designed as an introductory course in energy involving six simple machines, electricity, magnetism, and motion. The booklet lists the relevant state-adopted texts and states the performance objectives for the unit. It provides an outline of the course content and suggests experiments, demonstrations, field trips, and…

  17. Trends in experimental high-energy physics

    SciTech Connect

    Sanford, T.W.L.

    1982-06-01

    Data from a scan of papers in Physical Review Letters and Physical Review are used to demonstrate that American high-energy physicists show a pattern of accelerator and instrumentation usage characteristic of that expected from the logistic-substitution model of Marchetti and of Fischer and Pry.

  18. Comparison of calculated and experimental results of fragmenting cylinder experiments

    SciTech Connect

    WILSON,L.T.; REEDAL,D.R.; KIPP,MARLIN E.; MARTINEZ,REINA R.; GRADY,D.E.

    2000-06-02

    The Grady-Kipp fragmentation model provides a physically based method for determining the fracture and breakup of materials under high loading rates. Recently, this model has been implemented into the CTH Shock Physics Code and has been used to simulate several published experiments. Materials studied in this paper are AerMet 100 steel and a 90% tungsten alloy. The experimental geometry consists of a right circular cylinder filled with an explosive main charge that is initiated at its center. The sudden expansion of the resulting detonation products causes fracture of the cylinder. Strain rates seen in the cylinder are on the order of 10{sup 4} s{sup {minus}1}. The average fragment sizes calculated with the Grady-Kipp fragmentation model successfully replicate the mean fragment size obtained from the experimental fragment distribution. When Poisson statistics are applied to the calculated local average fragment sizes, good correlation is also observed with the shape of the experimental cumulative fragment distribution. The experimental fragmentation results, CTH numerical simulations, and correlation of these numerical results with the experimental data are described.

  19. INTERFACE DEFEAT OF LONG RODS IMPACTING BOROSILICATE GLASS EXPERIMENTAL RESULTS

    DTIC Science & Technology

    2009-02-01

    UNCLASSIFIED UNCLASSIFIED Interface Defeat of Long Rods Impacting Borosilicate Glass Experimental Results Charles E. Anderson, Jr. Thilo Behner...6. AUTHOR(S) Charles E. Anderson, Jr.1, Thilo Behner2, Dennis L. Orphal3, Timothy J. Holmquist4, Volker Hohler2, , and Matthias Wickert2 5f. WORK

  20. CSI sensing and control: Analytical and experimental results

    NASA Technical Reports Server (NTRS)

    Junkins, J. L.; Pollock, T. C.; Rahman, Z. H.

    1989-01-01

    Recent work on structural identification and large-angle maneuvers with vibration suppression was presented. The recent work has sought to balance structural and controls analysis activities by involving the analysts directly in the validation and experimental aspects of the research. Some new sensing, actuation, system identification, and control concepts were successfully implemented. An overview of these results is given.

  1. Design and experimental results for the S809 airfoil

    SciTech Connect

    Somers, D M

    1997-01-01

    A 21-percent-thick, laminar-flow airfoil, the S809, for horizontal-axis wind-turbine applications, has been designed and analyzed theoretically and verified experimentally in the low-turbulence wind tunnel of the Delft University of Technology Low Speed Laboratory, The Netherlands. The two primary objectives of restrained maximum lift, insensitive to roughness, and low profile drag have been achieved. The airfoil also exhibits a docile stall. Comparisons of the theoretical and experimental results show good agreement. Comparisons with other airfoils illustrate the restrained maximum lift coefficient as well as the lower profile-drag coefficients, thus confirming the achievement of the primary objectives.

  2. Design and experimental results for the S805 airfoil

    SciTech Connect

    Somers, D.M.

    1997-01-01

    An airfoil for horizontal-axis wind-turbine applications, the S805, has been designed and analyzed theoretically and verified experimentally in the low-turbulence wind tunnel of the Delft University of Technology Low Speed Laboratory, The Netherlands. The two primary objectives of restrained maximum lift, insensitive to roughness, and low profile drag have been achieved. The airfoil also exhibits a docile stall. Comparisons of the theoretical and experimental results show good agreement. Comparisons with other airfoils illustrate the restrained maximum lift coefficient as well as the lower profile-drag coefficients, thus confirming the achievement of the primary objectives.

  3. Experimental results for a hypersonic nozzle/afterbody flow field

    NASA Technical Reports Server (NTRS)

    Spaid, Frank W.; Keener, Earl R.; Hui, Frank C. L.

    1995-01-01

    This study was conducted to experimentally characterize the flow field created by the interaction of a single-expansion ramp-nozzle (SERN) flow with a hypersonic external stream. Data were obtained from a generic nozzle/afterbody model in the 3.5 Foot Hypersonic Wind Tunnel at the NASA Ames Research Center, in a cooperative experimental program involving Ames and McDonnell Douglas Aerospace. The model design and test planning were performed in close cooperation with members of the Ames computational fluid dynamics (CFD) team for the National Aerospace Plane (NASP) program. This paper presents experimental results consisting of oil-flow and shadow graph flow-visualization photographs, afterbody surface-pressure distributions, rake boundary-layer measurements, Preston-tube skin-friction measurements, and flow field surveys with five-hole and thermocouple probes. The probe data consist of impact pressure, flow direction, and total temperature profiles in the interaction flow field.

  4. Experimental results for correlation-based wavefront sensing

    SciTech Connect

    Poyneer, L A; Palmer, D W; LaFortune, K N; Bauman, B

    2005-07-01

    Correlation wave-front sensing can improve Adaptive Optics (AO) system performance in two keys areas. For point-source-based AO systems, Correlation is more accurate, more robust to changing conditions and provides lower noise than a centroiding algorithm. Experimental results from the Lick AO system and the SSHCL laser AO system confirm this. For remote imaging, Correlation enables the use of extended objects for wave-front sensing. Results from short horizontal-path experiments will show algorithm properties and requirements.

  5. Experimental results of a predictive neural network HVAC controller

    SciTech Connect

    Jeannette, E.; Assawamartbunlue, K.; Kreider, J.F.; Curtiss, P.S.

    1998-12-31

    Proportional, integral, and derivative (PID) control is widely used in many HVAC control processes and requires constant attention for optimal control. Artificial neural networks offer the potential for improved control of processes through predictive techniques. This paper introduces and shows experimental results of a predictive neural network (PNN) controller applied to an unstable hot water system in an air-handling unit. Actual laboratory testing of the PNN and PID controllers show favorable results for the PNN controller.

  6. Experimental investigations on energy harvesting performance of dielectric elastomers

    NASA Astrophysics Data System (ADS)

    Wang, Yongquan; Liu, Xuejing; Xue, Huanhuan; Chen, Hualing; Jia, Shuhai

    2014-03-01

    In this paper, the emerging technology of energy harvesting based on dielectric elastomers (DE), a new type of functional materials belonging to the family of Electroactive Polymers (EAPs), is presented with emphasis on its performance characteristics and some key influencing factors. At first, on the basic principle of DE energy harvesting, the effects of some control parameters are theoretically analyzed under certain mechanical and electrical constraints. Then, a type of annular DE generator using the commercial elastomers of VHB 4910 (3M, USA), is specially designed and fabricated. A series of experimental tests for the device's energy harvesting performance are implemented at different pre-stretch ratios, stretch amplitudes (displacements), and bias voltages in the constant charge (open-circuit) condition. The experiment results demonstrate the associated influence laws of the above control parameters on the performance of the DE generator, and have good consistent with those obtained from the theoretical analysis. This study is expected to provide a helpful guidance for the design and operation of practical DE energy harvesting devices/systems.

  7. An experimental high energy physics program

    NASA Astrophysics Data System (ADS)

    Gaidos, J. A.; Loeffler, F. J.; McIlwain, R. L.; Miller, D. H.; Palfrey, T. R.; Shibata, E. I.

    1989-05-01

    The CLEO detector accumulated, (approximately 480,000 B-mesons) the world's largest sample of B decays, before being shutdown in May 1988 for the installation of CLEO II. This data sample came from 335 pb(-1) accumulated at the upsilon (4S). The Cornell Electron Storage Ring set new luminosity records, reaching 3.5 pb(-1) in a single day. These data are being intensively analyzed and 21 papers were given at the Baltimore APS meeting. Among the highlights are: confirmation of B(sup 0)(bar B)(sup 0) mixing; discovery of the charm-strange baryon xi (sub c)(sup 0); limits on b yields u decay; and non-observation of B yields p(bar p)pi(pi), which was reported by the ARGUS collaboration. The construction of CLEO II is proceeding on schedule. The new 1.5 T superconducting magnet has passed all tests and all of the detector elements have been installed. This includes a 7800 CsI crystals electromagnetic shower calorimeter. The data from the Gamma Ray Astrophysics experiment show a significant signal for high energy gamma ray emission from Cygnus X-3 and also confirm the previously reported anomalous period from Her X-1. Meanwhile, the old 6 mirror telescope has been refitted with 26 high resolution mirrors and improved fast electronics. GRANDE, the next generation detector based on the water Cherenkov technique, has been formally proposed to HEPAP. The detector will search for neutrino emission in the Southern Hemisphere and gamma radiation in the Northern Hemisphere.

  8. Experimental Results of Pebble Beds Thermal Hydraulic Characteristics

    SciTech Connect

    Rimkevicius, S.; Uspuras, E.

    2006-07-01

    The purpose of this paper is to present the results of the experimental investigation of the thermal hydraulic characteristics for two types of test sections - thin annular pebble beds (i.e. spheres dumped in thin annular slots) and pebble beds placed between cylinders. The experimental results of heat transfer from the spheres and from a cylinder, as well as hydraulic drag for both types of test sections are presented in this paper. The results of performed experiments in the case of thin annular pebble beds demonstrated that maximum heat transfer and hydraulic drag is at the relative width of the annular slot K equal to 1.07 and 1.75 of spheres diameter. The heat transfer in internal layers at these values of K is equal to the heat transfer in the internal layers of large (unlimited) rhombic packing. The results of the experimental investigation of pebble beds between cylinders demonstrated that the randomly arranged pebble bed is preferable to the regular rhombic structure from the point of view of design simplicity, heat transfer from the cylinder and drag coefficient. (authors)

  9. Experimental results on the atmospheric muon charge ratio

    NASA Astrophysics Data System (ADS)

    Mauri, N.

    2016-07-01

    The atmospheric muon charge ratio, defined as the number of positive over negative charged muons, is a highly informative observable both for cosmic rays and particle physics. It allows studying the features of high-energy hadronic interactions in the forward region and the composition of primary cosmic rays. In this review results from underground experiments measuring the charge ratio around 1 TeV are discussed. The measurements in the TeV energy region constrain the associated kaon production, which is particularly important e.g. for the calculation of the atmospheric neutrino flux.

  10. Design and Experimental Results for the S414 Airfoil

    DTIC Science & Technology

    2010-08-01

    of most current general-aviation aircraft, including busi - ness jets , as well as unmanned aerial vehicles and all sailplanes. It does, however...RDECOM TR 10-D-112 U.S. ARMY RESEARCH, DEVELOPMENT AND ENGINEERING COMMAND TITLE: Design and Experimental Results for the S414 Airfoil AUTHOR: Dan M...Somers and Mark D. Maughmer COMPANY NAME: Airfoils , Incorporated COMPANY ADDRESS: 122 Rose Drive Port Matilda PA 16870-7535 DATE: August 2010 FINAL

  11. Experimental overview of COMPASS and CLAS results on TMDs

    NASA Astrophysics Data System (ADS)

    Riedl, Caroline

    2016-03-01

    In the past years, distribution functions depending on the transverse momentum of partons in the nucleon (TMDs) have been intensely studied in spin physics. The TMDs represent one approach to disentangle the multi-dimensional structure of the nucleon. Correlations of the transverse spin of quarks with their transverse momentum can be observed by measuring spin azimuthal asymmetries. Experimental results from the COMPASS (CERN) and CLAS (Jefferson Laboratory) collaborations are presented and an outlook to upcoming measurements at these facilities is given.

  12. Mechanical properties of triaxially braided composites: Experimental and analytical results

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Foye, Raymond L.; Pastore, Christopher M.; Gowayed, Yasser A.

    1992-01-01

    This paper investigates the unnotched tensile properties of two-dimensional triaxial braid reinforced composites from both an experimental and analytical viewpoint. The materials are graphite fibers in an epoxy matrix. Three different reinforcing fiber architectures were considered. Specimens were cut from resin transfer molded (RTM) composite panels made from each braid. There were considerable differences in the observed elastic constants from different size strain gage and extensometer readings. Larger strain gages gave more consistent results and correlated better with the extensometer readings. Experimental strains correlated reasonably well with analytical predictions in the longitudinal, zero degree, fiber direction but not in the transverse direction. Tensile strength results were not always predictable even in reinforcing directions. Minor changes in braid geometry led to disproportionate strength variations. The unit cell structure of the triaxial braid was discussed with the assistence of computer analysis of the microgeometry. Photomicrographs of the braid geometry were used to improve upon the computer graphics representations of unit cells. These unit cells were used to predict the elastic moduli with various degrees of sophistication. The simple and the complex analyses were generally in agreement but none adequately matched the experimental results for all the braids.

  13. Mechanical properties of triaxially braided composites: Experimental and analytical results

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Foye, Raymond L.; Pastore, Christopher M.; Gowayed, Yasser A.

    1992-01-01

    The unnotched tensile properties of 2-D triaxial braid reinforced composites from both an experimental and an analytical viewpoint are studied. The materials are graphite fibers in an epoxy matrix. Three different reinforcing fiber architectures were considered. Specimens were cut from resin transfer molded (RTM) composite panels made from each braid. There were considerable differences in the observed elastic constants from different size strain gage and extensometer reading. Larger strain gages gave more consistent results and correlated better with the extensometer reading. Experimental strains correlated reasonably well with analytical predictions in the longitudinal, 0 degrees, fiber direction but not in the transverse direction. Tensile strength results were not always predictable even in reinforcing directions. Minor changes in braid geometry led to disproportionate strength variations. The unit cell structure of the triaxial braid was discussed with the assistance of computer analysis of the microgeometry. Photomicrographs of braid geometry were used to improve upon the computer graphics representations of unit cells. These unit cells were used to predict the elastic moduli with various degrees of sophistication. The simple and the complex analyses were generally in agreement but none adequately matched the experimental results for all the braids.

  14. Design and experimental results for the S814 airfoil

    SciTech Connect

    Somers, D.M.

    1997-01-01

    A 24-percent-thick airfoil, the S814, for the root region of a horizontal-axis wind-turbine blade has been designed and analyzed theoretically and verified experimentally in the low-turbulence wind tunnel of the Delft University of Technology Low Speed Laboratory, The Netherlands. The two primary objectives of high maximum lift, insensitive to roughness, and low profile drag have been achieved. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results show good agreement with the exception of maximum lift which is overpredicted. Comparisons with other airfoils illustrate the higher maximum lift and the lower profile drag of the S814 airfoil, thus confirming the achievement of the objectives.

  15. Experimental Results for Titan Aerobot Thermo-Mechanical Subsystem Development

    NASA Technical Reports Server (NTRS)

    Pauken, Michael T.; Hall, Jeffery L.

    2006-01-01

    This paper presents experimental results on a set of 4 thermo-mechanical research tasks aimed at Titan and Venus aerobots: 1. A cryogenic balloon materials development program culminating in the fabrication and testing of a 4.6 m long blimp prototype at 93K. 2. A combined computational and experimental thermal analysis of the effect of radioisotope power system (RPS) waste heat on the behavior of a helium filled blimp hull. 3. Aerial deployment and inflation testing using a blimp 4. A proof of concept experiment with an aerobot-mounted steerable high gain antenna These tasks were supported with JPL internal R&D funds and executed by JPL engineers with substantial industry collaboration for Task #1, the cryogenic balloon materials

  16. Experimental investigation of fatigue in a cantilever energy harvesting beam

    NASA Astrophysics Data System (ADS)

    Avvari, Panduranga Vittal; Yang, Yaowen; Liu, Peiwen; Soh, Chee Kiong

    2015-03-01

    Over the last decade, cantilever energy harvesters gained immense popularity owing to the simplicity of the design and piezoelectric energy harvesting (PEH) using the cantilever design has undergone considerable evolution. The major drawback of a vibrating cantilever beam is its vulnerability to fatigue over a period of time. This article brings forth an experimental investigation into the phenomenon of fatigue of a PEH cantilever beam. As there has been very little literature reported in this area, an effort has been made to scrutinize the damage due to fatigue in a linear vibrating cantilever PEH beam consisting of an aluminum substrate with a piezoelectric macro-fiber composite (MFC) patch attached near the root of the beam and a tip mass attached to the beam. The beam was subjected to transverse vibrations and the behavior of the open circuit voltage was recorded with passing time. Moreover, electro-mechanical admittance readings were obtained periodically using the same MFC patch as a Structural health monitoring (SHM) sensor to assess the health of the PEH beam. The results show that with passing time the PEH beam underwent fatigue in both the substrate and MFC, which is observed in a complimentary trend in the voltage and admittance readings. The claim is further supported using the variation of root mean square deviation (RMSD) of the real part of admittance (conductance) readings. Thus, this study concludes that the fatigue issue should be addressed in the design of PEH for long term vibration energy harvesting.

  17. Experimental and simulational result multipactors in 112 MHz QWR injector

    SciTech Connect

    Xin, T.; Ben-Zvi, I.; Belomestnykh, S.; Brutus, J. C.; Skaritka, J.; Wu, Q.; Xiao, B.

    2015-05-03

    The first RF commissioning of 112 MHz QWR superconducting electron gun was done in late 2014. The coaxial Fundamental Power Coupler (FPC) and Cathode Stalk (stalk) were installed and tested for the first time. During this experiment, we observed several multipacting barriers at different gun voltage levels. The simulation work was done within the same range. The comparison between the experimental observation and the simulation results are presented in this paper. The observations during the test are consisted with the simulation predictions. We were able to overcome most of the multipacting barriers and reach 1.8 MV gun voltage under pulsed mode after several round of conditioning processes.

  18. ANOVA parameters influence in LCF experimental data and simulation results

    NASA Astrophysics Data System (ADS)

    Delprete, C.; Sesanaa, R.; Vercelli, A.

    2010-06-01

    The virtual design of components undergoing thermo mechanical fatigue (TMF) and plastic strains is usually run in many phases. The numerical finite element method gives a useful instrument which becomes increasingly effective as the geometrical and numerical modelling gets more accurate. The constitutive model definition plays an important role in the effectiveness of the numerical simulation [1, 2] as, for example, shown in Figure 1. In this picture it is shown how a good cyclic plasticity constitutive model can simulate a cyclic load experiment. The component life estimation is the subsequent phase and it needs complex damage and life estimation models [3-5] which take into account of several parameters and phenomena contributing to damage and life duration. The calibration of these constitutive and damage models requires an accurate testing activity. In the present paper the main topic of the research activity is to investigate whether the parameters, which result to be influent in the experimental activity, influence the numerical simulations, thus defining the effectiveness of the models in taking into account of all the phenomena actually influencing the life of the component. To obtain this aim a procedure to tune the parameters needed to estimate the life of mechanical components undergoing TMF and plastic strains is presented for commercial steel. This procedure aims to be easy and to allow calibrating both material constitutive model (for the numerical structural simulation) and the damage and life model (for life assessment). The procedure has been applied to specimens. The experimental activity has been developed on three sets of tests run at several temperatures: static tests, high cycle fatigue (HCF) tests, low cycle fatigue (LCF) tests. The numerical structural FEM simulations have been run on a commercial non linear solver, ABAQUS®6.8. The simulations replied the experimental tests. The stress, strain, thermal results from the thermo structural FEM

  19. [Experimental Conditions and Reliability Analysis of Results of COD components].

    PubMed

    Li, Zhi-hua; Zhang, Yin; Han, Xing; Yu, Ke; Li, Ru-jia

    2015-10-01

    The present study attempts to use SF( OUR(max)/OUR(en)) instead of S(0)/X(0) as an index of optimal initial conditions for determination of COD components by means of respirometry, thereby simplifying the measuring process and the operation can be automated. Further, the ratio of COD consumed by the growth of biomass can be used for the reliability assessment of results. Experimental results show that, experimental conditions for obtaining good results as follows: (1) for samples that composed of a large amount of easily biodegradable components (e. g., synthetic wastewater made by sodium acetate), SF should be in the range of 2.8 to 5.3, and the ratio of COD consumed by growth of biomass should be less than 30%; (2) for samples that composed of both readily biodegradable and slowly biodegradable components (i. e., typical domestic wastewater), SF should be in the range of 5.8 to 6.4, and the ratio of COD consumed by growth of biomass should be less than 30%; (3) and for samples that composed of a large amount of slowly biodegradable industrial wastewater (i. e., landfill leachate), SF should be 15 or less, and the ratio of COD consumed by growth of biomass should be approximately 40%. Therefore, when respirometry is used for the determination of COD components, the optimal conditions in terms of SF increase with the complexity of carbon source.

  20. Sheet Hydroforming Process Numerical Model Improvement Through Experimental Results Analysis

    NASA Astrophysics Data System (ADS)

    Gabriele, Papadia; Antonio, Del Prete; Alfredo, Anglani

    2010-06-01

    The increasing application of numerical simulation in metal forming field has helped engineers to solve problems one after another to manufacture a qualified formed product reducing the required time [1]. Accurate simulation results are fundamental for the tooling and the product designs. The wide application of numerical simulation is encouraging the development of highly accurate simulation procedures to meet industrial requirements. Many factors can influence the final simulation results and many studies have been carried out about materials [2], yield criteria [3] and plastic deformation [4,5], process parameters [6] and their optimization. In order to develop a reliable hydromechanical deep drawing (HDD) numerical model the authors have been worked out specific activities based on the evaluation of the effective stiffness of the blankholder structure [7]. In this paper after an appropriate tuning phase of the blankholder force distribution, the experimental activity has been taken into account to improve the accuracy of the numerical model. In the first phase, the effective capability of the blankholder structure to transfer the applied load given by hydraulic actuators to the blank has been explored. This phase ended with the definition of an appropriate subdivision of the blankholder active surface in order to take into account the effective pressure map obtained for the given loads configuration. In the second phase the numerical results obtained with the developed subdivision have been compared with the experimental data of the studied model. The numerical model has been then improved, finding the best solution for the blankholder force distribution.

  1. Silicon drift detector with reduced lateral diffusion:. experimental results

    NASA Astrophysics Data System (ADS)

    Šonský, J.; Valk, H.; Huizenga, J.; Hollander, R. W.; van Eijk, C. W. E.; Sarro, P. M.

    2000-01-01

    In a standard multi-anode silicon drift detector electron cloud broadening during the drifting towards the anode pixels deteriorates the energy and position resolution. This makes the detector less applicable for detection of low-energy X-rays. The signal charge sharing between several anodes can be eliminated by introducing sawtooth-shaped p + field strips. The sawtooth structure results in small electric fields directed parallel to the sensor surface and perpendicular to the drift direction which produce gutters. The drifting electrons are confined in these gutters of one saw tooth period wide. For a detector with a sawtooth period of 500 μm, we have measured the maximum number of fully confined electrons as a function of the potential gutter depth induced by different sawtooth angles.

  2. Comparison of Calculated and Experimental Results for a Boiling/Condensing Experimental Facility

    SciTech Connect

    Carbajo, Juan J; McDuffee, Joel Lee; Felde, David K

    2016-01-01

    A new experimental facility for materials irradiation and testing at the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) is being developed. Details of this facility have been presented before [1, 2]. A prototype of this facility, the Thermo-Syphon Test Loop (TSTL) has been built and experimental data have been obtained and analyzed [3, 4]. Pre-test calculations for this facility with the RELAP5-3D code [5] have been presented previously [6] as well as other calculations [7, 8] with the TRACE code [9]. The results of both codes were very different [7]. RELAP5-3D predicted much higher pressures and temperatures than TRACE. This paper compares calculated results with the TSTL experimental data.

  3. Effects of magnetic soil on metal detectors: preliminary experimental results

    NASA Astrophysics Data System (ADS)

    Das, Y.

    2007-04-01

    In a series of previous papers, analytical results dealing with the effects of soil electromagnetic properties on the performance of induction metal detectors were reported. In this paper experimental data are provided to verify some previously reported results. The time-domain response of a magnetic soil half-space and a small metallic sphere situated in air as well as buried in the soil were measured using a purpose-designed system based on a modified Schiebel AN19/2 metal detector. As in the previous work, the sphere is chosen as a simple prototype for the small metal parts in low-metal landmines. The soil used was Cambodian "laterite" with dispersive magnetic susceptibility, which serves as a good model for soils that are known to adversely affect the performance of metal detectors. The metal object used was a sphere of diameter 0.0254 m made of 6061-T6 aluminum. Experimental data are in good agreement with theoretical predictions. Data also show that for the weakly magnetic soil used in the experiments, the total response of the buried sphere is the sum of the response of the soil and that of the sphere placed in air. This finding should simplify the prediction or measurement of response of buried targets as one can separately measure/compute the response of an object in air and that of the host media and simply add the two. This simplification may not be possible for soils that are more strongly magnetic.

  4. Single And Double Pulse Irradiation And Comparison With Experimental Results

    SciTech Connect

    Fornarini, L.; Fantoni, R.; Colao, F.; Santagata, A.; Teghil, R.

    2009-09-27

    A theoretical model of laser ablation has been previously developed and applied to Laser Induced Breakdown Spectroscopy (LIBS) analysis of bronzes with the aim to improve quantitative results and to focus on problems arising in the interpretation of experimental data. The model describes laser-solid matter interaction, plume expansion, plasma formation and laser-plasma interaction. A two temperature approach has been also introduced to take into account the initial temperature dynamics of the alloy surface upon ultra-short laser irradiation. We examined various target compositions, typical of archaeological artworks, and different laser characteristics such as wavelength (355 nm, 530 nm, 1064 nm) and pulse duration (8 ns, 250 fs). In this work, the model has been extended to simulate double pulse LIBS configuration in order to clarify the mechanism involved in the process and for better interpreting the experimental data. Plasma composition, relevant parameters (temperature, electron density) and their kinetic evolutions have been measured. Results have been compared with the simulation obtained using the same irradiation conditions and set of targets.

  5. Electrical and thermal behavior of unsaturated soils: experimental results

    NASA Astrophysics Data System (ADS)

    Nouveau, Marie; Grandjean, Gilles; Leroy, Philippe; Philippe, Mickael; Hedri, Estelle; Boukcim, Hassan

    2016-05-01

    When soil is affected by a heat source, some of its properties are modified, and in particular, the electrical resistivity due to changes in water content. As a result, these changes affect the thermal properties of soil, i.e., its thermal conductivity and diffusivity. We experimentally examine the changes in electrical resistivity and thermal conductivity for four soils with different grain size distributions and clay content over a wide range of temperatures, from 20 to 100 °C. This temperature range corresponds to the thermal conditions in the vicinity of a buried high voltage cable or a geothermal system. Experiments were conducted at the field scale, at a geothermal test facility, and in the laboratory using geophysical devices and probing systems. The results show that the electrical resistivity decreases and the thermal conductivity increases with temperature up to a critical temperature depending on soil types. At this critical temperature, the air volume in the pore space increases with temperature, and the resulting electrical resistivity also increases. For higher temperatures , the thermal conductivity increases sharply with temperature up to a second temperature limit. Beyond it, the thermal conductivity drops drastically. This limit corresponds to the temperature at which most of the water evaporates from the soil pore space. Once the evaporation is completed, the thermal conductivity stabilizes. To explain these experimental results, we modeled the electrical resistivity variations with temperature and water content in the temperature range 20 - 100°C, showing that two critical temperatures influence the main processes occurring during heating at temperatures below 100 °C.

  6. Experimental determination of stress variation threshold resulted in earthquake triggering

    NASA Astrophysics Data System (ADS)

    Novikova, Elena; Novikov, Victor; Okunev, Vladimir; Klyuchkin, Vadim

    2014-05-01

    There are many field observations of earthquake triggering by static and dynamic stress variations caused by impact of distant strong earthquakes, underground chemical and nuclear explosions, solar-lunar earth tides, strong variations of atmospheric pressure etc., as well as by electric current injection into the Earth crust. It is supposed that the external impacts on the earthquake source result in exceeding the threshold stress and earthquake triggering. Nevertheless, the mechanisms of the earthquake triggering phenomena is not clear, and the problem of determination of stress variation threshold resulted in initiation of seismic events is very important. At present, based on analysis of field observations of dynamic triggering of earthquakes (by wave train from distant strong earthquakes) performed for various regions, including the USA, Japan, China, Greece, etc. it is considered that the triggering threshold of stress variations is about of 500 kPa. An experimental study at the spring-slider system was carried out for detailed study of behavior of fault area under near-to-failure state and experimental triggering impacts, as well as for determination of the threshold variation of normal stress in the fault gauge resulted in earthquake (slip) triggering. The spring-slider system provides a spring loading rate of 0.001 to 0.02 mm/s. The travelling block of dimensions 250x120x65 mm is connected with electromechanical drive via the spring with 9.5 N/mm spring constant. The normal stress of the travelling block is up to 30 kPa. For determination of the triggering threshold of normal stress variations the electromagnetic system was activated by control system at the level of 0.98-0.99 critical (fault failure) shear stress, which provided reducing the normal stress (by 0.001% to 0.1%) in the form of rectangular pulses of 0.5 to 5.0 s duration generated in time interval of 20 to 40 s. The level of stress variation impact resulted in the slip of travelling block (with

  7. Experimental and theoretical research in high energy astrophysics

    NASA Technical Reports Server (NTRS)

    Clark, George W.

    1990-01-01

    NASA grants to MIT for investigations in experimental and theoretical high energy astrophysics have, over the years, nurtured the infrastructure development and experimental activities that have led to successful proposals for the OSO 7, SAS 3, HEAO 1, and HEAO 2 missions and to the achievements in high energy astrophysics of the MIT Group. This report consists of excerpts from the progress reports of 1988 through 1990 that have been submitted as a regular feature of the renewal requests. These excerpts convey the flavor of the grant-supported activities, and a sense of the progress that has been made in each of the areas investigations.

  8. Ultrasonic scattering by blood: theories, experimental results and biomedical applications

    NASA Astrophysics Data System (ADS)

    Shung, K. Kirk

    2002-05-01

    In this paper, theoretical and experimental efforts that have been undertaken to better understand the phenomenon of ultrasonic scattering in blood will be reviewed. This subject is of interest in biology and medicine because the echoes generated by blood are used to extract blood velocity by ultrasonic Doppler flow and imaging devices. In the course of these investigations it became clear that ultrasonic scattering from blood is dependent upon such hematological and hemodynamic properties of blood as hematocrit, plasma protein concentration, flow rate and flow cycle duration. Several aspects of these experimental results have been successfully modeled by recent theoretical developments. An unexpected consequence of these efforts is that ultrasound appears to be a viable tool for blood flow visualization and hemodynamic measurements. Two unique hemodynamic phenomena that have never been reported in the hemodynamic literature have been observed: the black hole, a low echogenic zone in the center stream of whole blood flowing in a blood vessel under steady flow and the collapsing ring, an echogenic ring appearing near the periphery of a vessel at the beginning of a flow cycle, converging toward the center, and eventually collapsing during pulsatile flow. Similar observations have been made during clinical scanning of patients.

  9. Aeolian Simulations: A Comparison of Numerical and Experimental Results

    NASA Astrophysics Data System (ADS)

    Mathews, O.; Burr, D. M.; Bridges, N. T.; Lyne, J. E.; Marshall, J. R.; Greeley, R.; White, B. R.; Hills, J.; Smith, K.; Prissel, T. C.; Aliaga-Caro, J. F.

    2010-12-01

    Aeolian processes are a major geomorphic agent on solid planetary bodies with atmospheres (Earth, Mars, Venus, and Titan). This paper describes preliminary efforts to model aeolian saltation using computational fluid dynamics (CFD) and to compare the results with those obtained in wind tunnel testing conducted in the Planetary Aeolian Laboratory at NASA Ames Research Center at ambient pressure. The end goal of the project is to develop an experimentally validated CFD approach for modeling aeolian sediment transport on Titan and other planetary bodies. The MARSWIT open-circuit tunnel in this work was specifically designed for atmospheric boundary layer studies. It is a variable-speed, continuous flow tunnel with a test section 1.0 m by 1.2 m in size; the tunnel is able to operate at pressures from 10 millibar to one atmosphere. Flow trips near the tunnel inlet ensure a fully developed, turbulent boundary layer in the test section. Wind speed and axial velocity profiles can be measured with a traversing pitot tube. In this study, sieved walnut shell particles (Greeley et al. 1976) with a density of ~1.1 g/cm3 were used to correlate the low gravity conditions and low sediment density on a body of interest to that of Earth. This sediment was placed in the tunnel, and the freestream airspeed raised to 5.4 m/s. A Phantom v12 camera imaged the resulting particle motion at 1000 frames per second, which was analyzed with ImageJ open-source software (Fig. 1). Airflow in the tunnel was modeled with FLUENT, a commercial CFD program. The turbulent scheme used in FLUENT to obtain closed-form solutions to the Navier-Stokes equations was a 1st Order, k-epsilon model. These methods produced computational velocity profiles that agree with experimental data to within 5-10%. Once modeling of the flow field had been achieved, a Euler-Lagrangian scheme was employed, treating the particles as spheres and tracking each particle at its center. The particles are assumed to interact with

  10. Solving and Learning Soft Temporal Constraints: Experimental Setting and Results

    NASA Technical Reports Server (NTRS)

    Rossi, F.; Sperduti, A.; Venable, K. B.; Khatib, L.; Morris, P.; Morris, R.; Clancy, Daniel (Technical Monitor)

    2002-01-01

    Soft temporal constraints problems allow to describe in a natural way scenarios where events happen over time and preferences are associated to event distances and durations. However, sometimes such local preferences are difficult to set, and it may be easier instead to associate preferences to some complete solutions of the problem. Machine learning techniques can be useful in this respect. In this paper we describe two solvers (one more general and the other one more efficient) for tractable subclasses of soft temporal problems, and we show some experimental results. The random generator used to build the problems on which tests are performed is also described. We also compare the two solvers highlighting the tradeoff between performance and representational power. Finally, we present a learning module and we show its behavior on randomly-generated examples.

  11. Physical mechanism of comet outbursts - An experimental result

    NASA Technical Reports Server (NTRS)

    Hartmann, William K.

    1993-01-01

    Attention is given to an experimental investigation of the physical mechanism of comet outbursts which is consistent with the general picture of mantle presence on comets and clarifies the relation of mantles to eruptive activity. The experiment and closeup observation of Comet P/Halley suggest a result different from most mathematical models in that the release of gas pressure does not occur only from uniform gas flow out of the entire surface. In some active comets near perihelion within a few AU of the sun, gas production rates and disturbance of the surface may be so high that the outflow is nearly continuous, with the regolith being entirely stripped away, as in many of the models. The present model provides a cyclic eruption and recharge mechanism which is lacking in most other models.

  12. Beta decay and the origins of biological chirality - Experimental results

    NASA Technical Reports Server (NTRS)

    Gidley, D. W.; Rich, A.; Van House, J.; Zitzewitz, P. W.

    1982-01-01

    Preliminary experimental results are presented of an investigation of the possible role of preferential radiolysis by electrons emitted in the beta decay of radionuclides, a parity-nonconserving process, in the universal causation of the optical activity of biological compounds. Experiments were designed to measure the asymmetry in the production of triplet positronium upon the bombardment of an amino acid powder target by a collimated beam of positrons as positron helicity or target chirality is reversed. No asymmetry down to a level of 0.0007 is found in experiments on the D and L forms of cystine and tryptophan, indicating an asymmetry in positronium formation cross section of less than 0.01, while an asymmetry of 0.0031 is found for leucine, corresponding to a formation cross section asymmetry of about 0.04

  13. Object impedance control for cooperative manipulation - Theory and experimental results

    NASA Technical Reports Server (NTRS)

    Schneider, Stanley A.; Cannon, Robert H., Jr.

    1989-01-01

    The dynamic control module being developed in the Dynamic and Strategic Control of Cooperative Manipulators (DASCCOM) project at the Stanford University Aerospace Robotics Laboratory is described. First, the cooperative manipulation problem is analyzed from a systems perspective, and the desirable features of a control system for cooperative manipulation are discussed. Next, a control policy is developed that enforces a controlled impedance not of the individual arm endpoints, but of the manipulated object itself. A parallel implementation for a multiprocessor system is presented. The controller fully compensates for the system dynamics and directly controls the object internal forces. Most importantly, it presents a simple, powerful, intuitive interface to the strategic controller. Experimental results for a dual two-link arm robotic system are presented to verify the controllers performance, for both free-motion slews and environmental contact.

  14. Experimental Results of Rover-Based Coring and Caching

    NASA Technical Reports Server (NTRS)

    Backes, Paul G.; Younse, Paulo; DiCicco, Matthew; Hudson, Nicolas; Collins, Curtis; Allwood, Abigail; Paolini, Robert; Male, Cason; Ma, Jeremy; Steele, Andrew; Conrad, Pamela G.

    2011-01-01

    Experimental results are presented for experiments performed using a prototype rover-based sample coring and caching system. The system consists of a rotary percussive coring tool on a five degree-of-freedom manipulator arm mounted on a FIDO-class rover and a sample caching subsystem mounted on the rover. Coring and caching experiments were performed in a laboratory setting and in a field test at Mono Lake, California. Rock abrasion experiments using an abrading bit on the coring tool were also performed. The experiments indicate that the sample acquisition and caching architecture is viable for use in a 2018 timeframe Mars caching mission and that rock abrasion using an abrading bit may be feasible in place of a dedicated rock abrasion tool.

  15. Experimental results on indoor electromagnetic wave absorber using magnetic wood

    NASA Astrophysics Data System (ADS)

    Oka, Hideo; Narita, Koichi; Osada, Hiroshi; Seki, Kyoushirou

    2002-05-01

    The purpose of this paper is to propose a new type of indoor electromagnetic wave absorber using magnetic wood. This magnetic wood has good electromagnetic wave absorbing characteristics, a low specific gravity, a wood texture and other wood characteristics and can be easily processed. Electromagnetic wave absorbing characteristics were measured for four types of magnetic wood. The sandwich-type magnetic wood demonstrated the best wave absorbing characteristics among the four types of magnetic wood that were studied. The experimental results showed that the proposed indoor electromagnetic wave absorber can be used to suppress the transmission and reception of cellular phone and Personal Handy Phone System (PHS) signals and can be used as a cross protection for indoor wireless Local Area Networks (LAN). This wood can be processed for use in furniture, building materials, and other applications.

  16. Object impedance control for cooperative manipulation - Theory and experimental results

    NASA Technical Reports Server (NTRS)

    Schneider, Stanley A.; Cannon, Robert H., Jr.

    1992-01-01

    This paper presents the dynamic control module of the Dynamic and Strategic Control of Cooperating Manipulators (DASCCOM) project at Stanford University's Aerospace Robotics Laboratory. First, the cooperative manipulation problem is analyzed from a systems perspective, and the desirable features of a control system for cooperative manipulation are discussed. Next, a control policy is developed that enforces a controlled impedance not of the individual arm endpoints, but of the manipulated object itself. A parallel implementation for a multiprocessor system is presented. The controller fully compensates for the system dynamics and directly controls the object internal forces. Most importantly, it presents a simple, powerful, intuitive interface to higher level strategic control modules. Experimental results from a dual two-link-arm robotic system are used to compare the object impedance controller with other strategies, both for free-motion slews and environmental contact.

  17. Experimental Results on Shock-Wave Interaction on Compression Ramps

    NASA Astrophysics Data System (ADS)

    Passaro, A.; Fantoni, G.; Biagioni, L.; Cardone, G.

    2005-02-01

    A set of new experimental tests was carried out with intrusive and non-intrusive measurements related to Shock-Wave Boundary-Layer Interaction (SWBLI) on a 15 deg compression ramp model in a Mach 6 flow with total enthalpy of 1.8-2.5 MJ/kg. The facility was the modified High Enthalpy Arc-heated Tunnel at Alta, Pisa, Italy, with improved performance and diagnostics, in order to provide good control on the actual properties of the tunnel flow. The model shape and test conditions were the same of the previous test campaign carried out during the FESTIP programme. The new results confirmed a good agreement between intrusive and non-intrusive measurements and were also compared with success with numerical predictions, eventually explaining the discrepancy on wall heat flux that was found on the previous test campaign.

  18. Robotic follower experimentation results: ready for FCS increment I

    NASA Astrophysics Data System (ADS)

    Jaczkowski, Jeffrey J.

    2003-09-01

    Robotics is a fundamental enabling technology required to meet the U.S. Army's vision to be a strategically responsive force capable of domination across the entire spectrum of conflict. The U. S. Army Research, Development and Engineering Command (RDECOM) Tank Automotive Research, Development & Engineering Center (TARDEC), in partnership with the U.S. Army Research Laboratory, is developing a leader-follower capability for Future Combat Systems. The Robotic Follower Advanced Technology Demonstration (ATD) utilizes a manned leader to provide a highlevel proofing of the follower's path, which operates with minimal user intervention. This paper will give a programmatic overview and discuss both the technical approach and operational experimentation results obtained during testing conducted at Ft. Bliss, New Mexico in February-March 2003.

  19. Registration of multimodal brain images: some experimental results

    NASA Astrophysics Data System (ADS)

    Chen, Hua-mei; Varshney, Pramod K.

    2002-03-01

    Joint histogram of two images is required to uniquely determine the mutual information between the two images. It has been pointed out that, under certain conditions, existing joint histogram estimation algorithms like partial volume interpolation (PVI) and linear interpolation may result in different types of artifact patterns in the MI based registration function by introducing spurious maxima. As a result, the artifacts may hamper the global optimization process and limit registration accuracy. In this paper we present an extensive study of interpolation-induced artifacts using simulated brain images and show that similar artifact patterns also exist when other intensity interpolation algorithms like cubic convolution interpolation and cubic B-spline interpolation are used. A new joint histogram estimation scheme named generalized partial volume estimation (GPVE) is proposed to eliminate the artifacts. A kernel function is involved in the proposed scheme and when the 1st order B-spline is chosen as the kernel function, it is equivalent to the PVI. A clinical brain image database furnished by Vanderbilt University is used to compare the accuracy of our algorithm with that of PVI. Our experimental results show that the use of higher order kernels can effectively remove the artifacts and, in cases when MI based registration result suffers from the artifacts, registration accuracy can be improved significantly.

  20. Experimental Results of Integrated Refrigeration and Storage System Testing

    NASA Technical Reports Server (NTRS)

    Notardonato, W. U.; Johnson, W. L.; Jumper, K.

    2009-01-01

    Launch operations engineers at the Kennedy Space Center have identified an Integrated Refrigeration and Storage system as a promising technology to reduce launch costs and enable advanced cryogenic operations. This system uses a close cycle Brayton refrigerator to remove energy from the stored cryogenic propellant. This allows for the potential of a zero loss storage and transfer system, as well and control of the state of the propellant through densification or re-liquefaction. However, the behavior of the fluid in this type of system is different than typical cryogenic behavior, and there will be a learning curve associated with its use. A 400 liter research cryostat has been designed, fabricated and delivered to KSC to test the thermo fluid behavior of liquid oxygen as energy is removed from the cryogen by a simulated DC cycle cryocooler. Results of the initial testing phase focusing on heat exchanger characterization and zero loss storage operations using liquid oxygen are presented in this paper. Future plans for testing of oxygen densification tests and oxygen liquefaction tests will also be discussed. KEYWORDS: Liquid Oxygen, Refrigeration, Storage

  1. Experimental and computational study of the mean energy of electrons backscattered from surface films

    SciTech Connect

    Dapor, Maurizio; Rau, Eduard I.; Sennov, Ruslan A.

    2007-09-15

    Experimental measurements and Monte Carlo simulation of the mean energy of backscattered electrons by Au/Si targets irradiated by electron beams have been made as a function of the Au layer thickness for primary electron energies in the range 8-20 keV. The simulated trends are compared to experimental data. The mean backscattered energy as a function of the layer thickness presents a maximum whose position depends on the primary energy. The simulated and experimental behaviors are in satisfactory agreement. Similarities and differences between experimental and Monte Carlo results are illustrated and briefly discussed. A somewhat unexpected effect is observed: the maximum of the mean backscattered energy of layered targets is higher than that of the elements constituting the system. This effect is discussed on the basis of semi-empirical considerations.

  2. Experimental Results for Titan Aerobot Thermo-Mechanical Subsystem Development

    NASA Technical Reports Server (NTRS)

    Hall, Jeffrey L.; Jones, J. A.; Kerzhanovich, V. V.; Lachenmeier, T.; Mahr, P.; Pauken, M.; Plett, G. A.; Smith, L.; VanLuvender, M. L.; Yavrouian, A. H.

    2006-01-01

    This paper describes experimental results from a development program focused in maturing Titan aerobot technology in the areas of mechanical and thermal subsystems. Results from four key activities are described: first, a cryogenic balloon materials development program involving coupon and cylinder tests and culminating in the fabrication and testing of an inflated 4.6 m long prototype blimp at 93 K; second, a combined lab experiment and numerical simulation effort to assess potential problems resulting from radioisotope thermal generator waste heat generation near an inflated blimp; third, an aerial deployment and inflation development program consisting of laboratory and helicopter drop tests on a near full scale (11 m long) prototype blimp; and fourth, a proof of concept experiment demonstrating the viability of using a mechanically steerable high gain antenna on a floating blimp to perform direct to Earth telecommunications from Titan. The paper provides details on all of these successful activities and discusses their impact on the overall effort to produce mature systems technology for future Titan aerobot missions.

  3. Internal wave emission from baroclinic jets: experimental results

    NASA Astrophysics Data System (ADS)

    Borcia, Ion D.; Rodda, Costanza; Harlander, Uwe

    2016-04-01

    Large-scale balanced flows can spontaneously radiate meso-scale inertia-gravity waves (IGWs) and are thus in fact unbalanced. While flow-dependent parameterizations for the radiation of IGWs from orographic and convective sources do exist, the situation is less developed for spontaneously emitted IGWs. Observations identify increased IGW activity in the vicinity of jet exit regions. A direct interpretation of those based on geostrophic adjustment might be tempting. However, directly applying this concept to the parameterization of spontaneous imbalance is difficult since the dynamics itself is continuously re-establishing an unbalanced flow which then sheds imbalances by GW radiation. Examining spontaneous IGW emission in the atmosphere and validating parameterization schemes confronts the scientist with particular challenges. Due to its extreme complexity, GW emission will always be embedded in the interaction of a multitude of interdependent processes, many of which are hardly detectable from analysis or campaign data. The benefits of repeated and more detailed measurements, while representing the only source of information about the real atmosphere, are limited by the non-repeatability of an atmospheric situation. The same event never occurs twice. This argues for complementary laboratory experiments, which can provide a more focused dialogue between experiment and theory. Indeed, life cycles are also examined in rotating-annulus laboratory experiments. Thus, these experiments might form a useful empirical benchmark for theoretical and modeling work that is also independent of any sort of subgrid model. In addition, the more direct correspondence between experimental and model data and the data reproducibility makes lab experiments a powerful testbed for parameterizations. Here we show first results from a small rotating annulus experiments and we will further present our new experimental facility to study wave emission from jets and fronts.

  4. Experimental Results in DIS, SIDIS and DES from Jefferson Lab

    SciTech Connect

    Sebastian Kuhn

    2011-07-01

    Jefferson Lab's electron accelerator in its present incarnation, with a maximum beam energy slightly above 6 GeV, has already enabled a large number of experiments expanding our knowledge of nucleon and nuclear structure (especially in Deep Inelastic Scattering—DIS—at moderately high x, and in the resonance region). Several pioneering experiments have yielded first results on Deeply Virtual Compton Scattering (DVCS) and other Deep Exclusive Processes (DES), and the exploration of the rich landscape of transverse momentum-dependent (TMD) structure functions using Semi-Inclusive electron scattering (SIDIS) has begun. With the upgrade of CEBAF to 12 GeV now underway, a significantly larger kinematic space will become available. The 12 GeV program taking shape will complete a detailed mapping of inclusive, TMD and generalized distribution functions for quarks, antiquarks and gluons in the valence region and beyond.

  5. Experimental Results in DIS, SIDIS and DES from Jefferson Lab

    SciTech Connect

    Kuhn, Sebastian E.

    2011-07-15

    Jefferson Lab's electron accelerator in its present incarnation, with a maximum beam energy slightly above 6 GeV, has already enabled a large number of experiments expanding our knowledge of nucleon and nuclear structure (especially in Deep Inelastic Scattering--DIS--at moderately high x, and in the resonance region). Several pioneering experiments have yielded first results on Deeply Virtual Compton Scattering (DVCS) and other Deep Exclusive Processes (DES), and the exploration of the rich landscape of transverse momentum-dependent (TMD) structure functions using Semi-Inclusive electron scattering (SIDIS) has begun. With the upgrade of CEBAF to 12 GeV now underway, a significantly larger kinematic space will become available. The 12 GeV program taking shape will complete a detailed mapping of inclusive, TMD and generalized distribution functions for quarks, antiquarks and gluons in the valence region and beyond.

  6. Experimental Studies of Elementary Particle Interactions at High Energies

    SciTech Connect

    Goulianos, Konstantin

    2013-07-31

    This is the final report of a program of research on ``Experimental Studies of Elementary Particle Interactions at High Energies'' of the High Energy Physics (HEP) group of The Rockefeller University. The research was carried out using the Collider Detector at Fermilab (CDF) and the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) at CERN. Three faculty members, two research associates, and two postdoctoral associates participated in this project. At CDF, we studied proton-antiproton collisions at an energy of 1.96 TeV. We focused on diffractive interactions, in which the colliding antiproton loses a small fraction of its momentum, typically less than 1%, while the proton is excited into a high mass state retaining its quantum numbers. The study of such collisions provides insight into the nature of the diffractive exchange, conventionally referred to as Pomeron exchange. In studies of W and Z production, we found results that point to a QCD-based interpretation of the diffractive exchange, as predicted in a data-driven phenomenology developed within the Rockefeller HEP group. At CMS, we worked on diffraction, supersymmetry (SUSY), dark matter, large extra dimensions, and statistical applications to data analysis projects. In diffraction, we extended our CDF studies to higher energies working on two fronts: measurement of the single/double diffraction and of the rapidity gap cross sections at 7 TeV, and development of a simulation of diffractive processes along the lines of our successful model used at CDF. Working with the PYTHIA8 Monte Carlo simulation authors, we implemented our model as a PYTHIA8-MBR option in PYTHIA8 and used it in our data analysis. Preliminary results indicate good agreement. We searched for SUSY by measuring parameters in the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM) and found results which, combined with other experimental constraints and theoretical considerations, indicate that the

  7. Reinforcement learning accounts for moody conditional cooperation behavior: experimental results

    PubMed Central

    Horita, Yutaka; Takezawa, Masanori; Inukai, Keigo; Kita, Toshimasa; Masuda, Naoki

    2017-01-01

    In social dilemma games, human participants often show conditional cooperation (CC) behavior or its variant called moody conditional cooperation (MCC), with which they basically tend to cooperate when many other peers have previously cooperated. Recent computational studies showed that CC and MCC behavioral patterns could be explained by reinforcement learning. In the present study, we use a repeated multiplayer prisoner’s dilemma game and the repeated public goods game played by human participants to examine whether MCC is observed across different types of game and the possibility that reinforcement learning explains observed behavior. We observed MCC behavior in both games, but the MCC that we observed was different from that observed in the past experiments. In the present study, whether or not a focal participant cooperated previously affected the overall level of cooperation, instead of changing the tendency of cooperation in response to cooperation of other participants in the previous time step. We found that, across different conditions, reinforcement learning models were approximately as accurate as a MCC model in describing the experimental results. Consistent with the previous computational studies, the present results suggest that reinforcement learning may be a major proximate mechanism governing MCC behavior. PMID:28071646

  8. Reinforcement learning accounts for moody conditional cooperation behavior: experimental results.

    PubMed

    Horita, Yutaka; Takezawa, Masanori; Inukai, Keigo; Kita, Toshimasa; Masuda, Naoki

    2017-01-10

    In social dilemma games, human participants often show conditional cooperation (CC) behavior or its variant called moody conditional cooperation (MCC), with which they basically tend to cooperate when many other peers have previously cooperated. Recent computational studies showed that CC and MCC behavioral patterns could be explained by reinforcement learning. In the present study, we use a repeated multiplayer prisoner's dilemma game and the repeated public goods game played by human participants to examine whether MCC is observed across different types of game and the possibility that reinforcement learning explains observed behavior. We observed MCC behavior in both games, but the MCC that we observed was different from that observed in the past experiments. In the present study, whether or not a focal participant cooperated previously affected the overall level of cooperation, instead of changing the tendency of cooperation in response to cooperation of other participants in the previous time step. We found that, across different conditions, reinforcement learning models were approximately as accurate as a MCC model in describing the experimental results. Consistent with the previous computational studies, the present results suggest that reinforcement learning may be a major proximate mechanism governing MCC behavior.

  9. Recent experimental results of KSTAR RF heating and current drive

    SciTech Connect

    Wang, S. J. Kim, J.; Jeong, J. H.; Kim, H. J.; Joung, M.; Bae, Y. S.; Kwak, J. G.

    2015-12-10

    The overview of KSTAR activities on ICRH, LHCD and ECH/CD including the last experimental results and future plan aiming for long-pulse high-beta plasma will be presented. Recently we achieved reasonable coupling of ICRF power to H-mode plasma through several efforts to increase system reliability. Power balance will be discussed on this experiment. LHCD is still struggling in the low power regime. Review of antenna spectrum for the higher coupling in H-mode plasma will be tried. ECH/CD provides 41 sec, 0.8 MW of heating power to support high-performance long-pulse discharge. Also, 170 GHz ECH system is integrated with the Plasma Control System (PCS) for the feedback controlling of NTM. Status and plan of ECH/CD will be discussed. Finally, helicon current drive is being prepared for the next stage of KSTAR operation. The hardware preparation and the calculation results of helicon current drive in KSTAR plasma will be discussed.

  10. Experimental Results of a Single Emittance Compensation Solenoidal Magnet

    NASA Astrophysics Data System (ADS)

    Palmer, D. T.; Wang, X. J.; Ben-Zvi, I.; Miller, R. H.; Skaritka, J.

    1997-05-01

    A new iron dominated single emittance compensation solenoidal magnet was designed to be integrated with the BNL/SLAC/UCLA 1.6 cell S-Band Photocathode RF Gun. This emittance compensated photoinjector is now in operation at the Brookhaven Accelerator Test Facility. It has produced a 300 pC electron bunches with a normalized rms transverse emittance of ɛ_n,rms = 0.7 π mm mrad. POISSON field maps were used with PARMELA to optimize the emittance compensation solenoidal magnet design. Magnetic field measurements show that at the cathode plane Bz <= 10 gauss for a peak magnetic field of B_z,max = 3 KG. Which is in agreement with POISSON simulation. A single emittance compensation solenoidal magnet will produces a initial angular momentum of the electron bunch that manifests itself in a initial magnetic emittance term that cannot be eliminated. This magnetic emittance ɛ_mag,n,rms scales as 0.01 π mm mrad per gauss at the cathode. Which is in agreement with PARMELA simulations. Experimental beam dynamics results are presented that show spot size and emittance as a function of cathode magnetic field. These results are compared to theory and simulations.

  11. Experimental results of an iodine plasma in PEGASES gridded thruster

    NASA Astrophysics Data System (ADS)

    Grondein, Pascaline; Aanesland, Ane

    2015-09-01

    In the electric gridded thruster PEGASES, both positive and negative ions are expelled after extraction from an ion-ion plasma. This ion-ion plasma is formed downstream a localized magnetic field placed a few centimeters from the ionization region, trapping and cooling down the electron to allow a better attachment to an electronegative gas. For this thruster concept, iodine has emerged as the most attractive option. Heavy, under diatomic form and therefore good for high thrust, its low ionization threshold and high electronegativity lead to high ion-ion densities and low RF power. After the proof-of-concept of PEGASES using SF6 as propellant, we present here experimental results of an iodine plasma studied inside PEGASES thruster. At solid state at standard temperature and pressure, iodine is heated to sublimate, then injected inside the chamber where the neutral gas is heated and ionized. The whole injection system is heated to avoid deposition on surfaces and a mass flow controller allows a fine control on the neutral gas mass flow. A 3D translation stage inside the vacuum chamber allows volumetric plasma studies using electrostatic probes. The results are also compared with the global model dedicated to iodine as propellant for electric gridded thrusters. This work has been done within the LABEX Plas@par project, and received financial state aid managed by the Agence Nationale de la Recherche, as part of the programme ``Investissements d'avenir.''

  12. Growth of lithium triborate crystals. II. Experimental results

    NASA Astrophysics Data System (ADS)

    Parfeniuk, C.; Samarasekera, I. V.; Weinberg, F.; Edel, J.; Fjeldsted, K.; Lent, B.

    1996-02-01

    In Part I [C. Parfeniuk, I.V. Samarasekera and F. Weinberg, J. Crystal Growth 158 (1996) 514], a mathematical model of the flux growth of lithium triborate (LBO) crystals was used to calculate the temperature distribution and fluid flow in the melt during growth. In this report the model results are related to experimental observations. Temperature measurements in the melt, for different crucible rotation rates, are compared to the corresponding temperatures determined from the model. Direct observations of fluid flow in the melt, using a transparent glycerol/water solution as a physical model, are related to the calculated flow paths and velocities. As the LBO crystal grows, the rejected MoO 3 flux concentrates ahead of the interface leading to the formation of eutectic phases. The factors leading to the formation of these phases are examined, using flow velocity values determined from the model. A number of LBO crystals were grown, first using convenient growth parameters, and then using parameters determined from the model results. The size and quality of the crystals obtained are discussed and related to the growth conditions.

  13. Results from computational and experimental modeling of runaway electron damage on plasma facing components

    SciTech Connect

    Niemer, K.A.; Gilligan, J.G.; Croessmann, C.D.

    1994-11-01

    The purpose of this research was to extend the theoretical and experimental knowledge of runaway electron damage-impact-bombardment on plasma facing components and materials in magnetic fusion devices. The emphasis of this work involved computational modeling and experimental studies to investigate runaway electron energy deposition and thermal response in plasma facing materials. The goals were: (1) to develop a computational model to study and analyze runaway electron damage; (2) to characterize runaway electron parameters; and (3) to perform experiments to analyze runaway electron damage. These goals were accomplished by first assembling the PTA code package. PTA is a unique application of PATRAN, the Integrated TIGER Series (ITS), and ABAQUS for modeling high energy electron impact on magnetic fusion materials and components. The PTA code package provides a three-dimensional, time dependent, computational code package which predicts material response from runaway bombardment under most runaway conditions (i.e., electron energy, incident angle, energy density, and deposition time). As part of this research, PTA was used to study energy deposition and material response in several design applications, to analyze damaged material, and to analyze several experiments. Runaway electron characterization was determined through parametric studies, analysis of damaged materials, and analysis of experimental results. Characterization provided information on electron energy, incident angle, current, deposition time, and volume of material impacted by runaway electrons. Finally an experiment was performed on the Advanced Toroidal Facility (ATF) at Oak Ridge National Laboratory to study runaway electron damage. The experiment provided information on the runaway electron energy and current in ATF, as well as supplemented the existing experimental knowledge of runaway electron damage.

  14. Experimental Analysis of Team Performance: Methodological Developments and Research Results.

    DTIC Science & Technology

    1982-07-06

    The effects of a cooperation contingency on behavior in a continuous three-person environment. Journal of the Experimental Analysis of Behavior , 25...J.V. Effects of a pairing contingency on behavior in a three-person programmed environment. Journal of the Experimental Analysis of Behavior , 1978

  15. Endothelin in cerebral vasospasm. Clinical and experimental results.

    PubMed

    Zimmermann, M

    1997-06-01

    Since their discovery in 1988, endothelins have attracted scientific interest because of their extremely potent and long lasting vasoconstrictive effects. In the clinical part of the study plasma and cerebrospinal fluid (CSF) concentrations of big endothelin-1, endothelin-1 and endothelin-3 in patients with aneurysmal subarachnoid hemorrhage (SAH) were measured serially for 2 weeks after the onset of SAH. Big endothelin-1 was the predominant peptide present in CSF. The CSF concentrations of big ET-1, ET-1 and ET-3 were significantly higher in older than in younger patients. In patients with cerebral vasospasm postoperative concentrations of endothelins in the CSF remained at or were increased above levels measured before surgery. The volume of hematoma in the basal cisterns was predictive of the concentrations of endothelins in CSF. In the experimental study the efficacy of the orally active endothelin-receptor-antagonist RO 47-0203 for the prevention of cerebral vasospasm after experimental SAH, using the canine two-hemorrhage model, was investigated. Twenty-eight beagle dogs were used in this laboratory experiment. Fourteen animals each were assigned to the treatment and to the control group. In the treatment group each dog received two single doses of 30 mg/kg RO 47-0203 orally per day. The diameter of the basilar artery decreased from 1.36 +/- 0.17 mm at day 1 to 1.19 +/- 0.23 mm at day 8 in the treatment group while in the control group the vessel diameter decreased from 1.48 +/- 0.19 mm at day 1 to 1.02 +/- 0.22 mm at day 8. These results corresponded to a decrease of vessel diameter of 13.1% +/- 11.2% in the treatment group and a decrease of vessel diameter of 30.7% +/- 12.4% in the control group (p < 0.001). Concentrations of endothelin-1 in CSF significantly increased with time after SAH. These results underline the important role of endothelin in the development of cerebral vasospasm, and gives for the first time evidence that prevention of cerebral

  16. Experimentally increasing sedentary behavior results in decreased life satisfaction

    PubMed Central

    Edwards, Meghan K.; Loprinzi, Paul D.

    2017-01-01

    Background: No study has experimentally manipulated sedentary behavior and evaluated its effect on life satisfaction. Thus, the purpose of this study was to evaluate the effects of a free-living, sedentary behavior-inducing randomized controlled intervention on life satisfaction. Methods: Active, young adults between the ages of 18-35 were recruited and randomly assigned into a sedentary behavior intervention group (n = 26) or a control group (n = 13). The intervention group participants were instructed to eliminate all exercise and restrict daily steps (as measured via pedometry) to 5000 or less per day for one week. The control group was instructed to maintain regular levels of exercise and other physical activity for one week. Both groups completed the Satisfaction with Life Scale (SWLS) pre-intervention and immediately post-intervention. Results: There was a significant group x time interaction (F = 32.75, P < 0.001), with post-hoc contrast tests indicating decreased SWLS score (indicating lower levels of life satisfaction) in the intervention group during Visit 2 (post-intervention) compared with Visit 1 (pre-intervention); this corresponded with a mean absolute (Visit 2 minus Visit 1) change of -8.58 (95% CI: -5.91, -11.24) for SWLS scores in the intervention group (31.1% reduction). Conclusion: A one-week sedentary behavior-inducing intervention may negatively impact life satisfaction in an active, young adult population. Regular physical activity may be imperative in avoiding negative life satisfaction-related consequences. PMID:28326289

  17. Experimental results of ITER cold circulators towards the performance demonstration

    NASA Astrophysics Data System (ADS)

    Bhattacharya, R.; Vaghela, H.; Sarkar, B.; Patel, P.; Das, J.; Srinivasa, M.; Isono, T.; Kawano, K.

    2017-02-01

    The cold circulators, the most challenging component of ITER cryo-distribution system, have been designed, manufactured and tested successfully at factory. The design point for the cold circulator has been specified as 2.21 kg/s at 4.3 K inlet temperature having 0.155 MPa pressure head, dedicated for the nominal operation of toroidal field (TF) superconducting magnet of ITER. The expected isentropic efficiency has been defined as 70 % or more suitable to cater the demands of the cryo-distribution system. Two cold circulators for TF superconducting magnet have been installed in the Test Auxiliary Cold Box (TACB) followed by the integration of TACB system with the 5.0 kW at 4.5 K class cryogenic test facility at Japan. Final cold acceptance test of the complete system has been performed in order to validate the design conditions of TACB and cold circulators. Qualification tests of two cold circulators have been executed at closed loop operating condition. The cool-down of cold circulators down to 4.6 K temperature level and normal operating results as well as the experimental validation of performance along with the obtained isentropic efficiencies at the operating conditions have been demonstrated meeting the system level requirements of ITER cryo-distribution.

  18. Shuttle Upper Atmosphere Mass Spectrometer Experimental Flight Results

    NASA Technical Reports Server (NTRS)

    Blanchard, R. C.; Ozoroski, Thomas A.; Nicholson, John Y.

    1994-01-01

    Calibrated pressure measurements for species with mass-to-charge ratios up to 50 amu/e(-) were obtained trom the shuttle upper atmosphere mass spectrometer experiment during re-entry on the STS-35 mission. The principal experimental objective is to obtain measurements of freestream density in the hypersonic rarefied flow flight regime. Data were collected from 180 to about 87 km. However, data above 115 km were contaminated from a source of gas emanating from pressure transdueers connected in parallel to the mass spectrometer. At lower altitudes, the pressure transducer data are compared to the mass spectrometer total pressure with excellent agreement. Near the orifice entrance, a significant amount of CO2 was generated from chemical reactions. The freestream density in the rarefied flow flight regime is calculated using an orifice pressure coefficient model based upon direct simulation Monte Carlo results. This density, when compared with the 1976 U.S. Standard Atmosphere model, exhibits the wavelike nature seen on previous flights using accelerometry. Selected spectra are presented at higher altitudes (320 km) showing the effects of the ingestion of gases from a forward fuselage fuel dump.

  19. Experimental results of a 30 m, 3-core HTSC cable

    NASA Astrophysics Data System (ADS)

    Masuda, Takato; Kato, Takeshi; Yumura, Hiroyasu; Hirose, Masayuki; Isojima, Shigeki; Honjo, Shoichi; Matsuo, Kimiyoshi; Mimura, Tomoo; Takahashi, Yoshihisa

    2002-08-01

    A high temperature superconducting (HTSC) cable is expected to transport large electric power with a compact size because of its high critical current density. We have been developing a 3-core 66 kV class HTSC cable, which is applied to the ∅150 mm duct, and is composed of a conductor and a shield wound with Ag-Mn sheathed Bi-2223 tapes, electrical insulation with polypropylene laminated paper impregnated with liquid nitrogen and thermal insulation with co-axial corrugated pipes. A 30 m, 3-core cable system has been constructed to verify the 3-core performance after its production, laying and cooling. The cable had good performance to mechanical stress in the factory process. The critical current of the cable was more than 2.4 kA at 77 K. The AC loss of the conductor part was 0.5 W/m/phase at 1 kA rms, which agreed well with the calculated value of the spiral pitch adjustment technique. A 130 kV rms AC was successfully applied without any change in tan δ and capacitance. As a next step, a 100 m HTSC cable has been designed and developed based on these experimental results.

  20. Designing Free Energy Surfaces That Match Experimental Data with Metadynamics

    DOE PAGES

    White, Andrew D.; Dama, James F.; Voth, Gregory A.

    2015-04-30

    Creating models that are consistent with experimental data is essential in molecular modeling. This is often done by iteratively tuning the molecular force field of a simulation to match experimental data. An alternative method is to bias a simulation, leading to a hybrid model composed of the original force field and biasing terms. Previously we introduced such a method called experiment directed simulation (EDS). EDS minimally biases simulations to match average values. We also introduce a new method called experiment directed metadynamics (EDM) that creates minimal biases for matching entire free energy surfaces such as radial distribution functions and phi/psimore » angle free energies. It is also possible with EDM to create a tunable mixture of the experimental data and free energy of the unbiased ensemble with explicit ratios. EDM can be proven to be convergent, and we also present proof, via a maximum entropy argument, that the final bias is minimal and unique. Examples of its use are given in the construction of ensembles that follow a desired free energy. Finally, the example systems studied include a Lennard-Jones fluid made to match a radial distribution function, an atomistic model augmented with bioinformatics data, and a three-component electrolyte solution where ab initio simulation data is used to improve a classical empirical model.« less

  1. Designing Free Energy Surfaces That Match Experimental Data with Metadynamics

    SciTech Connect

    White, Andrew D.; Dama, James F.; Voth, Gregory A.

    2015-04-30

    Creating models that are consistent with experimental data is essential in molecular modeling. This is often done by iteratively tuning the molecular force field of a simulation to match experimental data. An alternative method is to bias a simulation, leading to a hybrid model composed of the original force field and biasing terms. Previously we introduced such a method called experiment directed simulation (EDS). EDS minimally biases simulations to match average values. We also introduce a new method called experiment directed metadynamics (EDM) that creates minimal biases for matching entire free energy surfaces such as radial distribution functions and phi/psi angle free energies. It is also possible with EDM to create a tunable mixture of the experimental data and free energy of the unbiased ensemble with explicit ratios. EDM can be proven to be convergent, and we also present proof, via a maximum entropy argument, that the final bias is minimal and unique. Examples of its use are given in the construction of ensembles that follow a desired free energy. Finally, the example systems studied include a Lennard-Jones fluid made to match a radial distribution function, an atomistic model augmented with bioinformatics data, and a three-component electrolyte solution where ab initio simulation data is used to improve a classical empirical model.

  2. Experimental demonstration of photon upconversion via cooperative energy pooling.

    PubMed

    Weingarten, Daniel H; LaCount, Michael D; van de Lagemaat, Jao; Rumbles, Garry; Lusk, Mark T; Shaheen, Sean E

    2017-03-15

    Photon upconversion is a fundamental interaction of light and matter that has applications in fields ranging from bioimaging to microfabrication. However, all photon upconversion methods demonstrated thus far involve challenging aspects, including requirements of high excitation intensities, degradation in ambient air, requirements of exotic materials or phases, or involvement of inherent energy loss processes. Here we experimentally demonstrate a mechanism of photon upconversion in a thin film, binary mixture of organic chromophores that provides a pathway to overcoming the aforementioned disadvantages. This singlet-based process, called Cooperative Energy Pooling (CEP), utilizes a sensitizer-acceptor design in which multiple photoexcited sensitizers resonantly and simultaneously transfer their energies to a higher-energy state on a single acceptor. Data from this proof-of-concept implementation is fit by a proposed model of the CEP process. Design guidelines are presented to facilitate further research and development of more optimized CEP systems.

  3. Experimental demonstration of photon upconversion via cooperative energy pooling

    NASA Astrophysics Data System (ADS)

    Weingarten, Daniel H.; Lacount, Michael D.; van de Lagemaat, Jao; Rumbles, Garry; Lusk, Mark T.; Shaheen, Sean E.

    2017-03-01

    Photon upconversion is a fundamental interaction of light and matter that has applications in fields ranging from bioimaging to microfabrication. However, all photon upconversion methods demonstrated thus far involve challenging aspects, including requirements of high excitation intensities, degradation in ambient air, requirements of exotic materials or phases, or involvement of inherent energy loss processes. Here we experimentally demonstrate a mechanism of photon upconversion in a thin film, binary mixture of organic chromophores that provides a pathway to overcoming the aforementioned disadvantages. This singlet-based process, called Cooperative Energy Pooling (CEP), utilizes a sensitizer-acceptor design in which multiple photoexcited sensitizers resonantly and simultaneously transfer their energies to a higher-energy state on a single acceptor. Data from this proof-of-concept implementation is fit by a proposed model of the CEP process. Design guidelines are presented to facilitate further research and development of more optimized CEP systems.

  4. Experimental results on finite-beta limits and transport in the ISX-B tokamak

    SciTech Connect

    Bates, S.C.; Bush, C.E.; Carreras, B.A.; Cooper, W.A.; Dunlap, J.L.; Edmonds, P.H.; Eldridge, O.C.; England, A.C.; Gardner, W.L.; Hogan, J.T.

    1983-10-01

    A summary of experimental results pertaining to plasma energy and particle transport in the Impurity Study Experiment (ISX-B) tokamak is presented. Emphasis is placed on results with neutral beam heating, usually in the co- direction (aligned with the plasma current), and the relative roles of various energy loss mechanisms are discussed. The derived electron thermal diffusivity and the predictions of various models have been compared. The measured values are within a factor of 2 of the values expected to result from resistive pressure-driven modes. Evidence for the presence of these modes is discussed. Values of ion thermal diffusivity are compared with the predictions of neoclassical theory. Anomaly factors (the ratio of experimental value to theoretical value) between 1 and 5 are found. Comparisons between experimental results and theoretical predictions are also made for cases with increased toroidal field ripple, produced by using only 9 of the 18 toroidal field coils. Convection is shown to play a small role in energy transport, except at the plasma periphery. The behavior of both plasma and impurity particles is discussed and shown to be strongly dependent on the direction of the plasma current relative to the neutral beam (coinjection and counterinjection). Beta limits are discussed. The maximum values obtained for both ..beta../sub I/ (approx. 2) and <..beta..> (approx. 2.5%) are not thought to be limited except by the restricted power available for heating.

  5. Bolus-tracking arterial spin labelling: theoretical and experimental results

    NASA Astrophysics Data System (ADS)

    Kelly, M. E.; Blau, C. W.; Kerskens, C. M.

    2009-03-01

    Arterial spin labelling (ASL) is a magnetic resonance imaging (MRI) technique that can be used to provide a quantitative assessment of cerebral perfusion. Despite the development of a number of theoretical models to facilitate quantitative ASL, some key challenges still remain. The purpose of this study is to develop a novel quantitative ASL method based on a macroscopic model that reduces the number of variables required to describe the physiological processes involved. To this end, a novel Fokker-Planck equation consisting of stochastically varying macroscopic variables was derived from a general Langevin equation. ASL data from the rat brain was acquired using a bolus-tracking ASL protocol where a bolus of labelled spins flowing from an inversion plane in the neck into an imaging plane in the brain can be observed. Bolus durations of 1.5 s, 2.0 s and 3.0 s were used and the solution to the Fokker-Planck equation for the boundary conditions of bolus-tracking ASL was fitted to the experimental data using a least-squares fit. The mean transit time (MTT) and capillary transit time (CTT) were calculated from the first and second moments of the resultant curve respectively and the arterial transit time (ATT) was calculated by subtracting the CTT from the MTT. The average MTT, CTT and ATT values were 1.75 ± 0.22 s, 1.43 ± 0.12 s and 0.32 ± 0.04 s respectively. In conclusion, a new ASL protocol has been developed by combining the theoretical model with ASL experiments. The technique has the unique ability to provide solutions for varying bolus volumes and the generality of the new model is demonstrated by the derivation of additional solutions for the continuous and pulsed ASL (CASL and PASL) techniques.

  6. Experimental results on combined ultraviolet-proton excitation of moon rock luminescence.

    NASA Technical Reports Server (NTRS)

    Nash, D. B.

    1973-01-01

    The experimental results reported indicate that a small synergistic effect may exist between near-UV radiation and solar-wind-energy protons in solar radiation that could slightly enhance luminescence generation on the moon's surface. The magnitude of the effect, however, is far too small to account for the apparent orders-of-magnitude discrepancy between reported telescope measurements of lunar luminescence and the limitation of lunar luminescence intensity based on lab studies of moon rocks.

  7. Recent experimental results from a long-pulse J-band relativistic klystron amplifier developmental effort

    SciTech Connect

    Kato, K.G.; Crouch, D.D.; Sar, D.R.; Speciale, R.A.; Carlsten, B.E.; Fazio, M.V.; Haynes, W.B.; Stringfield, R.M.

    1994-12-31

    Recent experimental results, supporting simulations, and design modeling are presented from a developmental effort to a produce a long pulse ({approximately}1{mu}s) J-band (5.85-8.2 GHz) relativistic klystron amplifier (RKA) of the high current NRL genealogy. This RKA is designed to operate at approximately 6.6 GHz, with a desired RF output {approximately}700 MW. Conversion of electron beam energy to microwave energy is obtained by a mock magnetically insulated coaxial converter which, in various incarnations, can be made to be either a cavity gap extractor or an inverse cathode.

  8. Low Energy Solar Neutrino Spectroscopy:. Results from the Borexino Experiment

    NASA Astrophysics Data System (ADS)

    D'Angelo, D.

    2011-03-01

    neutrino oscillations. A further confirmations of the LMA scenario is provided by the absence of a day-night asymmetry in the 7Be signal. These experimental results allow to improve the knowledge of the pp neutrino flux, to place an upper limit on the CNO flux and also to explore non standard neutrino properties, improving the upper limit on the neutrino effective magnetic moment. Calibration campaigns aiming to reduce the systematical errors on fiducial volume definition and detector energy response have been performed and data analysis is presently in progress. Borexino has also recently observed antineutrinos from the Earth, for the first time at more the 3σ C.L. and has measured a rate of 3.9{ - 1.3}{ + 1.6} <=ft( {{ - 3.2}{ + 5.8} } ; ) events/(100ton-yr) at 68.3%(99.73%) C.L. Borexino is also a powerful supernova neutrino detector. Future prospects of the experiment include reducing the systematic error on the 7Be flux to below 5% and direct measurement of additional solar neutrino emissions such as pep, CNO and possibly pp.

  9. New experimental results on neutrino mixing and decay.

    NASA Astrophysics Data System (ADS)

    Oberauer, L.; von Feilitzsch, F.; Hagner, C.; Kempf, G.; Mößbauer, R. L.; Declais, Y.; Kajfasz, E.

    The search for neutrino decay is a sensitive method to look for very small neutrino mixing parameter. The authors report about the status of an decay experiment performed at a reactor in Bugey and present preliminary new experimental limits on the coupling of a heavy neutrino to the electron state. Additionally new experimental lifetime bounds on the radiative decay mode are given. Rigid laboratory limits on this decay mode for the hypothetical 17 keV neutrino are presented. Limits on the radiative decay of a 17 keV neutrino obtained from the supernova SN 1987A are discussed.

  10. OPERA and MINOS Experimental Result Prove Big Bang Theory Invalid

    NASA Astrophysics Data System (ADS)

    Pressler, David E.

    2012-03-01

    The greatest error in the history of science is the misinterpretation of the Michelson-Morley Experiment. The speed of light was measured to travel at the same speed in all three directions (x, y, z axis) in ones own inertial reference system; however, c will always be measured as having an absolute different speed in all other inertial frames at different energy levels. Time slows down due to motion or a gravity field. Time is the rate of physical process. Speed = Distance/Time. If the time changes the distance must change. Therefore, BOTH mirrors must move towards the center of the interferometer and space must contract in all-three-directions; C-Space. Gravity is a C-Space condition, and is the cause of redshift in our universe-not motion. The universe is not expanding. OPERA results are directly indicated; at the surface of earth, the strength of the gravity field is at maximum-below the earth's surface, time and space is less distorted, C-Space; therefore, c is faster. Newtonian mechanics dictate that a spherical shell of matter at greater radii, with uniform density, produces no net force on an observer located centrally. An observer located on the sphere's surface, like our Earth's or a large sphere, like one located in a remote galaxy, will construct a picture centered on himself to be identical to the one centered inside the spherical shell of mass. Both observers will view the incoming radiation, emitted by the other observer, as redshifted, because they lay on each others radial line. The Universe is static and very old.

  11. Experimental conformational energy maps of proteins and peptides.

    PubMed

    Balaji, Govardhan A; Nagendra, H G; Balaji, Vitukudi N; Rao, Shashidhar N

    2017-02-07

    We have presented an extensive analysis of the peptide backbone dihedral angles in the PDB structures and computed experimental Ramachandran plots for their distributions seen under a various constraints on X-ray resolution, representativeness at different sequence identity percentages, and hydrogen bonding distances. These experimental distributions have been converted into isoenergy contour plots using the approach employed previously by F. M. Pohl. This has led to the identification of energetically favored minima in the Ramachandran (ϕ, ψ) plots in which global minima are predominantly observed either in the right-handed α-helical or the polyproline II regions. Further, we have identified low energy pathways for transitions between various minima in the (ϕ,ψ) plots. We have compared and presented the experimental plots with published theoretical plots obtained from both molecular mechanics and quantum mechanical approaches. In addition, we have developed and employed a root mean square deviation (RMSD) metric for isoenergy contours in various ranges, as a measure (in kcal.mol(-1) ) to compare any two plots and determine the extent of correlation and similarity between their isoenergy contours. In general, we observe a greater degree of compatibility with experimental plots for energy maps obtained from molecular mechanics methods compared to most quantum mechanical methods. The experimental energy plots we have investigated could be helpful in refining protein structures obtained from X-ray, NMR, and electron microscopy and in refining force field parameters to enable simulations of peptide and protein structures that have higher degree of consistency with experiments. Proteins 2017. © 2017 Wiley Periodicals, Inc.

  12. Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

    NASA Technical Reports Server (NTRS)

    Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

    2013-01-01

    In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

  13. Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

    NASA Technical Reports Server (NTRS)

    Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

    2013-01-01

    In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 C temperature increase from the nominal vapor temperature. The 19 C temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

  14. How Do Pseudocapacitors Store Energy? Theoretical Analysis and Experimental Illustration.

    PubMed

    Costentin, Cyrille; Porter, Thomas R; Savéant, Jean-Michel

    2017-03-15

    Batteries and electrochemical double layer charging capacitors are two classical means of storing electrical energy. These two types of charge storage can be unambiguously distinguished from one another by the shape and scan-rate dependence of their cyclic voltammetric (CV) current-potential responses. The former shows peak-shaped current-potential responses, proportional to the scan rate v or to v(1/2), whereas the latter displays a quasi-rectangular response proportional to the scan rate. On the contrary, the notion of pseudocapacitance, popularized in the 1980s and 1990s for metal oxide systems, has been used to describe a charge storage process that is faradaic in nature yet displays capacitive CV signatures. It has been speculated that a quasi-rectangular CV response resembling that of a truly capacitive response arises from a series of faradaic redox couples with a distribution of potentials, yet this idea has never been justified theoretically. We address this problem by first showing theoretically that this distribution-of-potentials approach is closely equivalent to the more physically meaningful consideration of concentration-dependent activity coefficients resulting from interactions between reactants. The result of the ensuing analysis is that, in either case, the CV responses never yield a quasi-rectangular response ∝ ν, identical to that of double layer charging. Instead, broadened peak-shaped responses are obtained. It follows that whenever a quasi-rectangular CV response proportional to scan rate is observed, such reputed pseudocapacitive behaviors should in fact be ascribed to truly capacitive double layer charging. We compare these results qualitatively with pseudocapacitor reports taken from the literature, including the classic RuO2 and MnO2 examples, and we present a quantitative analysis with phosphate cobalt oxide films. Our conclusions do not invalidate the numerous experimental studies carried out under the pseudocapacitance banner but

  15. Laser ablation of a turbid medium: Modeling and experimental results

    SciTech Connect

    Brygo, F.; Semerok, A.; Weulersse, J.-M.; Thro, P.-Y.; Oltra, R.

    2006-08-01

    Q-switched Nd:YAG laser ablation of a turbid medium (paint) is studied. The optical properties (absorption coefficient, scattering coefficient, and its anisotropy) of a paint are determined with a multiple scattering model (three-flux model), and from measurements of reflection-transmission of light through thin layers. The energy deposition profiles are calculated at wavelengths of 532 nm and 1.064 {mu}m. They are different from those described by a Lambert-Beer law. In particular, the energy deposition of the laser beam is not maximum on the surface but at some depth inside the medium. The ablated rate was measured for the two wavelengths and compared with the energy deposition profile predicted by the model. This allows us to understand the evolution of the ablated depth with the wavelength: the more the scattering coefficient is higher, the more the ablated depth and the threshold fluence of ablation decrease.

  16. An Experimental and Theoretical High Energy Physics Program

    SciTech Connect

    Shipsey, Ian

    2012-07-31

    The Purdue High Energy Physics Group conducts research in experimental and theoretical elementary particle physics and experimental high energy astrophysics. Our goals, which we share with high energy physics colleagues around the world, are to understand at the most fundamental level the nature of matter, energy, space and time, and in order to explain the birth, evolution and fate of the Universe. The experiments in which we are currently involved are: CDF, CLEO-c, CMS, LSST, and VERITAS. We have been instrumental in establishing two major in-house facilities: The Purdue Particle Physics Microstructure Detector Facility (P3MD) in 1995 and the CMS Tier-2 center in 2005. The research efforts of the theory group span phenomenological and theoretical aspects of the Standard Model as well as many of its possible extensions. Recent work includes phenomenological consequences of supersymmetric models, string theory and applications of gauge/gravity duality, the cosmological implications of massive gravitons, and the physics of extra dimensions.

  17. The density-of-states concept versus the experimentally determined distribution of activation energies

    SciTech Connect

    Adriaenssens, G.J.; Arkhipov, V.I.

    1996-12-31

    Random fluctuations of localized state energies will result in thermal release of carriers trapped in those states at shorter times than would be observed from a stationary distribution of the same energies. An experimentally observed distribution of activation energies will hence differ from the distribution of average energies of the states involved. It will also be temperature-dependent. In a-Si:H, low-frequency fluctuations with a spectrum comparable to the one of 1/f noise, can account for the measured temperature dependence of the distribution. They also explain the apparent shift in localized-state energy under steady-state illumination.

  18. Experimental And Theoretical High Energy Physics Research At UCLA

    SciTech Connect

    Cousins, Robert D.

    2013-07-22

    This is the final report of the UCLA High Energy Physics DOE Grant No. DE-FG02- 91ER40662. This report covers the last grant project period, namely the three years beginning January 15, 2010, plus extensions through April 30, 2013. The report describes the broad range of our experimental research spanning direct dark matter detection searches using both liquid xenon (XENON) and liquid argon (DARKSIDE); present (ICARUS) and R&D for future (LBNE) neutrino physics; ultra-high-energy neutrino and cosmic ray detection (ANITA); and the highest-energy accelerator-based physics with the CMS experiment and CERN’s Large Hadron Collider. For our theory group, the report describes frontier activities including particle astrophysics and cosmology; neutrino physics; LHC interaction cross section calculations now feasible due to breakthroughs in theoretical techniques; and advances in the formal theory of supergravity.

  19. Conservation of Mechanical and Electric Energy: Simple Experimental Verification

    ERIC Educational Resources Information Center

    Ponikvar, D.; Planinsic, G.

    2009-01-01

    Two similar experiments on conservation of energy and transformation of mechanical into electrical energy are presented. Both can be used in classes, as they offer numerous possibilities for discussion with students and are simple to perform. Results are presented and are precise within 20% for the version of the experiment where measured values…

  20. Experimental Results for an Annular Aerospike with Differential Throttling

    NASA Technical Reports Server (NTRS)

    Ruf, Joseph H.; McDaniels, David M.

    2005-01-01

    A) MSFC funded an internal study on Altitude Compensating Nozzles: 1) Develop an ACN design and performance prediction tool. 2) Design, build and test cold flow ACN nozzles. 3) An annular aerospike nozzle was designed and tested. 4) Incorporated differential throttling to assess Thrust Vector Control. B) Objective of the test hardware: 1) Provide design tool verification. 2) Provide benchmark data for CFD calculations. 3) Experimentally measure side force, or TVC, for a differentially throttled annular aerospike.

  1. CP Violation in B Meson Decays: Experimental Results

    SciTech Connect

    Lanceri, Livio; /Trieste U. /INFN, Trieste

    2005-08-30

    CP violation is intimately connected with the puzzle of matter-antimatter asymmetry and baryogenesis. In the Standard Model of particle physics, the observed CP violation phenomena are accounted for by the Cabibbo-Kobayashi-Maskawa mechanism involving a phase in the quark mixing matrix. This paper is devoted to a review of the experimental status of CP violation in the decays of B mesons.

  2. Experimental and numerical investigation of energy dissipation in elastomeric rotational joint under harmonic loading

    NASA Astrophysics Data System (ADS)

    Jrad, Hanen; Dion, Jean Luc; Renaud, Franck; Tawfiq, Imad; Haddar, Mohamed

    2016-10-01

    This paper focuses on energy losses caused by inner damping and friction in an elastomeric rotational joint. A description of the design of a new experimental device intended to characterize dynamic stiffness in rotational elastomeric joint is presented. An original method based on Lagrange's equations, which allows accurately measuring forces and torques only with accelerometers, is proposed in order to identify dissipated energy in the rotational elastomeric joint. A rheological model developed taking into account dependence of the torque and the angular displacement (rotation). Experimental results and simulations used to quantify the dissipated energy in order to evaluate the damping ratio are presented and discussed.

  3. Analytical and experimental investigation of flexible longitudinal zigzag structures for enhanced multi-directional energy harvesting

    NASA Astrophysics Data System (ADS)

    Zhou, Shengxi; Hobeck, Jared D.; Cao, Junyi; Inman, Daniel J.

    2017-03-01

    This paper makes a complete investigation of flexible longitudinal zigzag (FLZ) energy harvesters for the purpose of enhancing energy harvesting from low-frequency and low-amplitude excitation. A general theoretical model of the FLZ energy harvesters with large joint block mass is proposed. In order to verify the accuracy of the theoretical model, both experimental results and finite element analysis via ANSYS software are presented. Results show that the theoretical model can successfully predict the dynamic response and the output power of the FLZ energy harvesters. Both theoretical and experimental results demonstrate that the proposed energy harvesters can effectively harvest vibration energy even when the direction of excitation relative to the harvester varies from 0° to 90°. Under the low excitation level of 0.18 m s‑2, the experimental maximum output power of a FLZ energy harvester with five beams was found to be 1.016 mW. Finally, the results indicate that the proposed structure is capable of effective energy conversion across a large range of excitation angles at low-frequency and low-amplitude excitations, which makes it suitable for a wide range of working conditions.

  4. Fracture mechanics analysis of composite microcracking - Experimental results in fatigue

    NASA Technical Reports Server (NTRS)

    Nairn, J. A.; Liu, S.

    1990-01-01

    The Nairn (1989) variational mechanics analysis, which yields the energy release rate of a microcrack's formation between two existing microcracks, has proven useful in the fracture mechanics interpretation of cross-ply laminates' microcracking. Attention is presently given to the application of this energy release rate analysis to a fracture mechanics-based interpretation of microcrack formation during fatigue loading, for the case of fatigue experiments on three layups of Avimid K/IM6 laminates and four layups of Fiberite 934/T300 laminates. The single master Paris-law plot onto which the data from all layups of a given material system fall is claimed to offer a complete characterization of that system's microcrack-formation resistance during fatigue loading.

  5. Optimal active vibration absorber: Design and experimental results

    NASA Technical Reports Server (NTRS)

    Lee-Glauser, Gina; Juang, Jer-Nan; Sulla, Jeffrey L.

    1992-01-01

    An optimal active vibration absorber can provide guaranteed closed-loop stability and control for large flexible space structures with collocated sensors/actuators. The active vibration absorber is a second-order dynamic system which is designed to suppress any unwanted structural vibration. This can be designed with minimum knowledge of the controlled system. Two methods for optimizing the active vibration absorber parameters are illustrated: minimum resonant amplitude and frequency matched active controllers. The Controls-Structures Interaction Phase-1 Evolutionary Model at NASA LaRC is used to demonstrate the effectiveness of the active vibration absorber for vibration suppression. Performance is compared numerically and experimentally using acceleration feedback.

  6. Experimental Studies of Ion Beam Neutralization: Preliminary Results

    SciTech Connect

    Ding, N.; Polansky, J.; Downey, R.; Wang, J.

    2011-05-20

    A testing platform is designed to study ion beam neutralization in the mesothermal, collisionless region. In the experimental setup, argon neutrals were ionized in a microwave cavity and accelerated by a plasma lens system which was biased to 2500 V above the system ground. Electrons were boiled off from two hot tungsten filaments to neutralize the ion beam. The plasma is diagnosed using Langmuir probe and Faraday probe. A 3-D traversing system and a complete data acquisition loop were developed to efficiently measure 3-D beam profile. Preliminary measurements of beam profiles are presented for different operating conditions.

  7. Experimental investigation of a packed bed thermal energy storage system

    NASA Astrophysics Data System (ADS)

    Cascetta, Mario; Cau, Giorgio; Puddu, Pierpaolo; Serra, Fabio

    2015-11-01

    In this work experimental investigations on a thermal energy storage system with a solid material as storage media and air as heat transfer fluid will be presented. The experimental test rig, installed at the DIMCM of the University of Cagliari, consists of a carbon steel tank filled with freely poured alumina beads that allows investigations of heat transfer phenomena in packed beds. The aim of this work is to show the influence of the operating conditions and physical parameters on thermocline formation and, in particular, the thermal behaviour of the thermal energy storage for repeated charging and discharging cycles. Better charging efficiency is obtained for lower values of mass flow rate and maximum air temperature and for increasing aspect ratio. A decreasing influence of the metal wall with continuous operation is also highlighted. In conclusion, the analysis focuses on the thermal hysteresis phenomenon, which causes degradation of the thermocline and the reduction of the energy that can be stored by the accumulator as the repeated number of cycles increases.

  8. CSI Flight Computer System and experimental test results

    NASA Technical Reports Server (NTRS)

    Sparks, Dean W., Jr.; Peri, F., Jr.; Schuler, P.

    1993-01-01

    This paper describes the CSI Computer System (CCS) and the experimental tests performed to validate its functionality. This system is comprised of two major components: the space flight qualified Excitation and Damping Subsystem (EDS) which performs controls calculations; and the Remote Interface Unit (RIU) which is used for data acquisition, transmission, and filtering. The flight-like RIU is the interface between the EDS and the sensors and actuators positioned on the particular structure under control. The EDS and RIU communicate over the MIL-STD-1553B, a space flight qualified bus. To test the CCS under realistic conditions, it was connected to the Phase-0 CSI Evolutionary Model (CEM) at NASA Langley Research Center. The following schematic shows how the CCS is connected to the CEM. Various tests were performed which validated the ability of the system to perform control/structures experiments.

  9. Geoacoustic and source tracking using particle filtering: experimental results.

    PubMed

    Yardim, Caglar; Gerstoft, Peter; Hodgkiss, William S

    2010-07-01

    A particle filtering (PF) approach is presented for performing sequential geoacoustic inversion of a complex ocean acoustic environment using a moving acoustic source. This approach treats both the environmental parameters [e.g., water column sound speed profile (SSP), water depth, sediment and bottom parameters] at the source location and the source parameters (e.g., source depth, range and speed) as unknown random variables that evolve as the source moves. This allows real-time updating of the environment and accurate tracking of the moving source. As a sequential Monte Carlo technique that operates on nonlinear systems with non-Gaussian probability densities, the PF is an ideal algorithm to perform tracking of environmental and source parameters, and their uncertainties via the evolving posterior probability densities. The approach is demonstrated on both simulated data in a shallow water environment with a sloping bottom and experimental data collected during the SWellEx-96 experiment.

  10. Guided wave modes in porous cylinders: experimental results.

    PubMed

    Wisse, C J; Smeulders, D M J; van Dongen, M E H; Chao, G

    2002-09-01

    In this paper guided wave modes in porous media are investigated. A water-saturated porous cylinder is mounted in the test section of a shock tube. Between the porous sample and the wall of the shock tube a water-filled annulus exists. For very small annulus width, bulk waves are generated and one-dimensional modeling is sufficient. Otherwise two-dimensional effects become important and multiple guided wave modes occur. Using a newly developed traversable positioning system in the shock tube, the frequency-dependent phase velocities and damping coefficients in the 1-120 kHz frequency range were measured. Prony's method was used for data processing. Agreement was found between the experimental data and the two-dimensional modeling of the shock tube which was based on Biot's theory.

  11. Automated modular high energy evaluation system for experimental thyristor devices

    NASA Astrophysics Data System (ADS)

    Lacouture, Shelby; Lawson, Kevin; Bayne, Stephen; Giesselmann, Michael; Scozzie, Charles J.; O'Brien, Heather; Ogunniyi, Aderinto A.

    2013-10-01

    A high energy, modular, completely automated test bed with integrated data acquisition and characterization systems was successfully designed in order to perform both safe operating area as well as very high volume reliability testing on experimental silicon carbide Super Gate Turn Off (SGTO) thyristors. Although the system follows a modular design philosophy, with each functional block acting as a peripheral to a main control module and can be adapted to arbitrary power and pulse width levels, for the specific SGTO devices initially evaluated it was configured to have the device discharge variable current levels of up to 6 kA into a 0.5 Ω resistive load with a relatively square pulse fixed at 100 μs full width at half maximum delivering energy levels up to 1.8 kJ to the load.

  12. Experimental results and modeling of a dynamic hohlraum on SATURN

    SciTech Connect

    Derzon, M.S.; Allshouse, G.O.; Deeney, C.; Leeper, R.J.; Nash, T.J.; Matuska, W.; Peterson, D.L.; MacFarlane, J.J.; Ryutov, D.D.

    1998-06-01

    Experiments were performed at SATURN, a high current z-pinch, to explore the feasibility of creating a hohlraum by imploding a tungsten wire array onto a low-density foam. Emission measurements in the 200--280 eV energy band were consistent with a 110--135 eV Planckian before the target shock heated, or stagnated, on-axis. Peak pinch radiation temperatures of nominally 160 eV were obtained. Measured early time x-ray emission histories and temperature estimates agree well with modeled performance in the 200--280 eV band using a 2D radiation magneto-hydrodynamics code. However, significant differences are observed in comparisons of the x-ray images and 2D simulations.

  13. Fuel Canister Stress Corrosion Cracking Susceptibility Experimental Results

    SciTech Connect

    Colleen Shelton-Davis

    2003-03-01

    The National Spent Nuclear Fuel Program is tasked with ensuring the U.S. Department of Energy (DOE)-owned spent nuclear fuel (SNF) is acceptable for permanent disposal at a designated repository. From a repository acceptance criteria viewpoint and from a transportation viewpoint, of significant concern is the condition of the container at the time of shipment. Because the fuel will be in temporary storage for as much as 50 years, verification that no significant degradation has occurred to the canister is required to preclude repackaging all the fuel. Many canisters are also being removed from wet storage, vacuum dried (hot or cold), and then placed into dry storage. This process could have a detrimental effect on canister integrity. Research is currently underway to provide a technically sound assessment of the expected canister condition at the end of interim storage.

  14. Experimental efforts and results in finding new heavy scintillators

    SciTech Connect

    Derenzo, S.E.; Moses, W.W.

    1992-09-01

    New heavy scintillators are being discovered with increasing frequency. In recent years NaI(Tl) (with its high light output and energy resolution) has been joined by BGO (with its high stopping power), BaF{sub 2} (with its excellent timing resolution), and CeF{sub 3} (with its speed and short Moliere radius). More than 10 potentially useful scintillators have been under development in the past five years, such as PbSO{sub 4} and Lu{sub 2}SiO{sub 5}(Ce). We tabulate the characteristics of these and other scintillators, including wavelength, luminous efficiency, decay time, and initial intensity. We describe a search strategy and the prospects for finding the ``ideal`` heavy scintillator, which would combine the light output of NaI(Tl) and CsI(Tl), the stopping power of BGO, and the speed of BaF{sub 2} and ZnO(Ga).

  15. Recent Experimental Results in the VX-10 Device

    NASA Astrophysics Data System (ADS)

    Squire, J. P.; Díaz, F. R. Chang; Jacobson, V. T.; McCaskill, G. E.; McCoy, J. E.; Petro, A. J.; Baity, F. W.; Bengtson, R. D.; Bering, E. A.; Garret, J. A.; Glover, T. W.

    2000-10-01

    In the VASIMR engine, neutral gas is ionized using a helicon type source and the ions are subsequently accelerated via ICRF power injection. The experimental device in the ASPL is targeting a total RF power level of 10 kW and is called VX-10. RF power is available with 3 kW at 25 MHz for the helicon source and 100 kW at 3 MHz for ICRF. Experiments with light gasses (hydrogen, deuterium, and helium) are performed. The VX-10 3-magnet system is capable of a maximum B field of 2 T and has flexible axial profile shaping capability. Diagnostics in the plasma exhaust include an RF compensated Langmuir probe, a Mach probe, Retarding Potential Analyzer (RPA), newly installed density interferometer and an ion gauge neutral pressure measurement. Parametric (e.g. magnetic field, gas flow, and RF power) studies are presented. Data indicate ion heating to more than 1 eV and acceleration by the magnetic exhaust with the helicon alone. ICRF experiments are beginning and initial data are presented.

  16. Experimental results with hydrogen fueled internal combustion engines

    NASA Technical Reports Server (NTRS)

    De Boer, P. C. T.; Mclean, W. J.; Homan, H. S.

    1975-01-01

    The paper focuses on the most important experimental findings for hydrogen-fueled internal combustion engines, with particular reference to the application of these findings to the assessment of the potential of hydrogen engines. Emphasis is on the various tradeoffs that can be made, such as between maximum efficiency, maximum power, and minimum NO emissions. The various possibilities for induction and ignition are described. Some projections are made about areas in which hydrogen engines may find their initial application and about optimum ways to design such engines. It is shown that hydrogen-fueled reciprocal internal combustion engines offer important advantages with respect to thermal efficiency and exhaust emissions. Problems arising from preignition can suitably be avoided by restricting the fuel-air equivalence ratio to values below about 0.5. The direct cylinder injection appears to be a very attractive way to operate the engine, because it combines a wide range of possible power outputs with a high thermal efficiency and very low NO emissions at part loads.

  17. Waste glass corrosion modeling: Comparison with experimental results

    SciTech Connect

    Bourcier, W.L.

    1993-11-01

    A chemical model of glass corrosion will be used to predict the rates of release of radionuclides from borosilicate glass waste forms in high-level waste repositories. The model will be used both to calculate the rate of degradation of the glass, and also to predict the effects of chemical interactions between the glass and repository materials such as spent fuel, canister and container materials, backfill, cements, grouts, and others. Coupling between the degradation processes affecting all these materials is expected. Models for borosilicate glass dissolution must account for the processes of (1) kinetically-controlled network dissolution, (2) precipitation of secondary phases, (3) ion exchange, (4) rate-limiting diffusive transport of silica through a hydrous surface reaction layer, and (5) specific glass surface interactions with dissolved cations and anions. Current long-term corrosion models for borosilicate glass employ a rate equation consistent with transition state theory embodied in a geochemical reaction-path modeling program that calculates aqueous phase speciation and mineral precipitation/dissolution. These models are currently under development. Future experimental and modeling work to better quantify the rate-controlling processes and validate these models are necessary before the models can be used in repository performance assessment calculations.

  18. Main experimental results of the Phebus Severe Fuel Damage Program

    SciTech Connect

    Gonnier, C. )

    1993-01-01

    The main objective of this program is to improve our knowledge about the early phase of a pressurized water reactor in-vessel core melt degradation in a temperature range up to 2800 K. The experimental program performed from December 1986 to June 1989 consists of six in-pile experiments with 21 fresh fuel rod bundles of 0.8 m active length. It is divided into two series of tests: (1) The first one (B9, B9R, B9+) is mainly devoted to the oxidation phenomenon and its consequences for fuel degradation. This series is characterized by high oxidation rates. (2) The second series [C3, C3+, Ag-In-CD (AIC)] is characterized by low oxidation rates of the cladding in order to study the interaction between the remaining Zircaloy and the other materials: interactions with Inconel and UO[sub 2] for C3 and C3+ tests and interactions with the Ag-In-Cd alloy and stainless steel of the control rod for the AIC test.

  19. EXPERIMENTAL RESULTS FROM A MICROWAVE CAVITY BEAM POSITION MONITOR.

    SciTech Connect

    BALAKIN,V.; BAZHAN,A.; LUNEV,P.; SOLYAK,N.; VOGEL,V.; ZHOGOLEV,P.; LISITSYN,A.; YAKIMENKO,V.

    1999-03-29

    Future Linear Colliders have hard requirements for the beam transverse position stability in the accelerator. A beam Position Monitor (BPM) with the resolution better than 0.1 micron in the single bunch regime is needed to control the stability of the beam position along the linac. Proposed BPM is based on the measurement of the asymmetrical mode excited by single bunch in the cavity. Four stages of signal processing (space-, time-, frequency- and phase-filtering providing the required signal-to-noise ratio) are used to obtain extremely high resolution. The measurement set-up was designed by BINP and installed at ATF/BNL to test experimentally this concept. The set-up includes three two-coordinates BPM's at the frequency of 13.566 GHz, and reference intensity/phase cavity. BPM's were mounted on support table. The two-coordinates movers allow to move and align BPM's along the straight line, using the signals from the beam. The position of each monitor is controlled by the sensors with the accuracy 0.03 micron. The information from three monitors allows to exclude angle and position jitter of the beam and measure BPM resolution. In the experiments the resolution of about 0.15 micron for 0.25 nC beam intensity was obtained, that is close to the value required.

  20. Construction of a WMR for Trajectory Tracking Control: Experimental Results

    PubMed Central

    Silva-Ortigoza, R.; Márquez-Sánchez, C.; Marcelino-Aranda, M.; Marciano-Melchor, M.; Silva-Ortigoza, G.; Bautista-Quintero, R.; Ramos-Silvestre, E. R.; Rivera-Díaz, J. C.; Muñoz-Carrillo, D.

    2013-01-01

    This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x1∗, y1∗),..., (xn∗, yn∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software. PMID:23997679

  1. Construction of a WMR for trajectory tracking control: experimental results.

    PubMed

    Silva-Ortigoza, R; Márquez-Sánchez, C; Marcelino-Aranda, M; Marciano-Melchor, M; Silva-Ortigoza, G; Bautista-Quintero, R; Ramos-Silvestre, E R; Rivera-Díaz, J C; Muñoz-Carrillo, D

    2013-01-01

    This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x₁∗, y₁∗),..., (x(n)∗, y(n)∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software.

  2. Modeling of rock friction 1. Experimental results and constitutive equations

    USGS Publications Warehouse

    Dieterich, J.H.

    1979-01-01

    Direct shear experiments on ground surfaces of a granodiorite from Raymond, California, at normal stresses of ??6 MPa demonstrate that competing time, displacement, and velocity effects control rock friction. It is proposed that the strength of the population of points of contacts between sliding surfaces determines frictional strength and that the population of contacts changes continuously with displacements. Previous experiments demonstrate that the strength of the contacts increases with the age of the contacts. The present experiments establish that a characteristic displacement, proportional to surface roughness, is required to change the population of contacts. Hence during slip the average age of the points of contact and therefore frictional strength decrease as slip velocity increases. Displacement weakening and consequently the potential for unstable slip occur whenever displacement reduces the average age of the contacts. In addition to this velocity dependency, which arises from displacement dependency and time dependency, the experiments also show a competing but transient increase in friction whenever slip velocity increases. Creep of the sliding surface at stresses below that for steady state slip is also observed. Constitutive relationships are developed that permit quantitative simulation of the friction versus displacement data as a function of surface roughness and for different time and velocity histories. Unstable slip in experiments is controlled by these constitutive effects and by the stiffness of the experimental system. It is argued that analogous properties control earthquake instability. Copyright ?? 1979 by the American Geophysical Union.

  3. Overview of Recent DIII-D Experimental Results

    NASA Astrophysics Data System (ADS)

    Fenstermacher, Max

    2015-11-01

    Recent DIII-D experiments have added to the ITER physics basis and to physics understanding for extrapolation to future devices. ELMs were suppressed by RMPs in He plasmas consistent with ITER non-nuclear phase conditions, and in steady state hybrid plasmas. Characteristics of the EHO during both standard high torque, and low torque enhanced pedestal QH-mode with edge broadband fluctuations were measured, including edge localized density fluctuations with a microwave imaging reflectometer. The path to Super H-mode was verified at high beta with a QH-mode edge, and in plasmas with ELMs triggered by Li granules. ITER acceptable TQ mitigation was obtained with low Ne fraction Shattered Pellet Injection. Divertor ne and Te data from Thomson Scattering confirm predicted drift-driven asymmetries in electron pressure, and X-divertor heat flux reduction and detachment were characterized. The crucial mechanisms for ExB shear control of turbulence were clarified. In collaboration with EAST, high beta-p scenarios were obtained with 80 % bootstrap fraction, high H-factor and stability limits, and large radius ITBs leading to low AE activity. Work supported by the US Department of Energy under DE-FC02-04ER54698 and DE-AC52-07NA27344.

  4. CPM and PDS -- A critical interpretation of experimental results

    SciTech Connect

    Stiebig, H.; Siebke, F.; Carius, R.

    1996-12-31

    CPM and PDS spectra of a-Si:H yield identical shape of the Urbach tail, while the defect absorption measured by PDS differs significantly from CPM. In this work an analysis of CPM and PDS spectra of annealed and degraded films is presented. Numerical simulations of CPM and PDS data, taking into account optical transitions, capture and emission processes as well as the Fermi level, yield information on the energy distribution and the charge state of the defects. The simulations reveal the coexistence of defects in the D{sup {minus}}, D{sup +} and D{sup 0} states. The defect distribution is dominated by charged states as predicted by the defect-pool model. Good agreement between measured and simulated PDS and CPM spectra can be obtained in the case of a homogeneous defect density. It is shown that differences between CPM and PDS are due to different sensitivities of the techniques to charged and neutral defect states. Microscopic inhomogeneities may cause significant additional differences.

  5. Overview of recent DIII-D experimental results

    NASA Astrophysics Data System (ADS)

    Fenstermacher, M. E.; LLNL; DIII-D Team

    2016-10-01

    Recent DIII-D experiments have contributed to the ITER physics basis and to physics understanding for extrapolation to future devices. Resonant Magnetic Perturbation ELM suppression was extended to lower shaping as a guide to joint experiments showing first ELM suppression in ASDEX-U. The physics model of suppression was validated in low torque ITER baseline plasmas. Toroidal variation of density gradients and turbulence was documented during RMP. Plasma rotation was predicted from measured scaling of intrinsic torque and momentum transport. Runaway electron plateau dissipation using SPI was demonstrated including new understanding of synchrotron and collisional damping effects. Good coupling of high frequency RF from a helicon antenna during H-mode was observed. Upstream pedestal density at divertor detachment decreased with increasing divertor closure. Bifurcations to detachment in H-mode with increasing density were reproduced with UEDGE including drifts. Sources, SOL transport and core accumulation of tungsten from toroidally continuous divertor target tiles were identified. Work supported by the US Department of Energy under DE-FC02-04ER54698 and DE-AC52-07NA27344.

  6. Experimental studies of pion-nucleus interactions at intermediate energies

    SciTech Connect

    Not Available

    1991-12-31

    This report summarizes the work on experimental research in intermediate energy nuclear physics carried out at New Mexico State University in 1991 under a great from the US Department of Energy. Most of these studies have involved investigations of various pion-nucleus interactions. The work has been carried out both with the LAMPF accelerator at the Los Alamos National Laboratory and with the cyclotron at the Paul Scherrer Institute (PSI) near Zurich, Switzerland. Part of the experimental work involves measurements of new data on double-charge-exchange scattering, using facilities at LAMPF which we helped modify, and on pion absorption, using a new detector system at PSI that covers nearly the full solid-angle region which we helped construct. Other work involved preparation for future experiments using polarized nuclear targets and a new high-resolution spectrometer system for detecting {pi}{sup 0} mesons. We also presented several proposals for works to be done in future years, involving studies related to pi-mesonic atoms, fundamental pion-nucleon interactions, studies of the difference between charged and neutral pion interactions with the nucleon, studies of the isospin structure of pion-nucleus interactions, and pion scattering from polarized {sup 3}He targets. This work is aimed at improving our understanding of the pion-nucleon interaction, of the pion-nucleus interaction mechanism, and of nuclear structure.

  7. Experimental results from a network-assisted PID controller

    SciTech Connect

    Curtiss, P.S.

    1996-11-01

    The results presented here are a continuation of studies on a neural-network-based controller. Part 1 is a summary of the previous studies, and Part 2 presents new results and offers some novel techniques used for training the network and making the entire package easier to use. The two major additions are (1) efficient use of training data for dramatically reducing memory requirements and (2) incorporation of a PID algorithm for performing control during training periods.

  8. Experimental Results for the Applicability of Multifractal Scaling in Turbulent Flows

    NASA Astrophysics Data System (ADS)

    Frederiksen, Richard D.; Dahm, Werner J. A.; Dowling, David R.

    1996-11-01

    Results are presented from an assessment of the applicability of multifractal scale similarity to the structure of conserved scalar fields ζ( x,t ) and scalar energy dissipation rate fields nabla ζ \\cdot nabla ζ ( x,t ) in turbulent flows. Two different types of experimental data are considered: fully resolved four-dimensional measurements of a Sc >> 1 conserved scalar field, and (2) long duration single point time series measurements of a Sc ≈ 1 conserved scalar field. Rigorous statistical criteria are developed to assess multifractal scale similarity and to discriminate between scale similar and random sets. Results show that the scalar energy dissipation rate field exhibits multifractal scaling at scales larger than the scalar diffusion length scale, λ_D. The multifractal scaling observed is consistent with that produced by a random multiplicative cascade process with a bilinear multiplier distribution. Similar analyses of the conserved scalar field find no evidence to support multifractal scaling over any range of scales.

  9. Pegasus liner stability experiments: Diagnostics and experimental results

    SciTech Connect

    Clark, D.A.; Morgan, D.V.; Rodriguez, G.

    1998-12-31

    A series of experiments to compare imploding cylindrical liner performance with Magneto-HydroDynamic (MHD) modeling has been performed at the Los Alamos National Laboratory Pegasus capacitor bank. Several configurations of aluminum liners have been used; some with initial perturbations and some smooth. Instability growth resulting from the perturbations has been observed with high resolution. Load diagnostics included radial x-rays, fiber optic impact pins, and VISAR (Velocity Interferometer for a Surface of Any Reflector). Diagnostic results and comparisons for several liner stability (LS) experiments are presented.

  10. Dense nonaqueous phase liquid tracer tests: experimental results.

    PubMed

    Burt, R A; Christians, G L; Williams, S P; Wilson, D J

    2001-12-01

    Two dense nonaqueous phase liquid (DNAPL) tracer tests were carried out in a shallow aquifer north of Fort Worth, TX. i-Propanol was used as the nonpartitioning tracer: n-hexanol and n-octanol were the partitioning tracers. Field data, mathematical modeling, the results of column tests, and field tracer tests with NaCl were used in designing the DNAPL tracer tests. The results indicated the presence of DNAPL at both sites tested; semi-quantitative estimates of the amounts of DNAPL present were obtained by mathematical modeling. Interpretation was complicated by heterogeneity of the aquifer and mass transport effects.

  11. Predictions for diffraction at the LHC compared to experimental results

    NASA Astrophysics Data System (ADS)

    Goulianos, Konstantin

    2014-04-01

    Diffractive proton-proton cross sections at the LHC, as well as the total and total-inelastic proton-proton cross sections, are predicted in a simple model obeying all unitarity constraints. The model has been implemented in the PYTHIA8-MBR event generator for single diffraction, double diffraction, and central diffraction processes. Predictions of the model are compared to recent LHC results.

  12. Joint Soviet-American experiment on hypokinesia: Experimental results

    NASA Technical Reports Server (NTRS)

    Burovskiy, N. N.

    1979-01-01

    Comprehensive results are reported from the Soviet portion of a joint Soviet-American experiment involving hypokinesia. The main emphases are on chemical analyses of blood and urine, functional tests, and examination of the cardiovascular system by electrocardiography, echocardiography, and plethysmography.

  13. Qualitative versus Quantitative Results: An Experimental Introduction to Data Interpretation.

    ERIC Educational Resources Information Center

    Johnson, Eric R.; Alter, Paula

    1989-01-01

    Described is an experiment in which the student can ascertain the meaning of a negative result from a qualitative test by performing a more sensitive quantitative test on the same sample. Methodology for testing urinary glucose with a spectrophotometer at 630 nm and with commercial assaying glucose strips is presented. (MVL)

  14. Experimental High Energy Physics Brandeis University Final Report

    SciTech Connect

    Blocker, Craig A.; Bensinger, James; Sciolla, Gabriella; Wellenstein, Hermann

    2013-07-26

    During the past three years, the Brandeis experimental particle physics group was comprised of four faculty (Bensinger, Blocker, Sciolla, and Wellenstein), one research scientist, one post doc, and ten graduate students. The group focused on the ATLAS experiment at LHC. In 2011, the LHC delivered 5/fb of pp colliding beam data at a center-of-mass energy of 7 TeV. In 2012, the center-of-mass energy was increased to 8 TeV, and 20/fb were delivered. The Brandeis group focused on two aspects of the ATLAS experiment -- the muon detection system and physics analysis. Since data taking began at the LHC in 2009, our group actively worked on ATLAS physics analysis, with an emphasis on exploiting the new energy regime of the LHC to search for indications of physics beyond the Standard Model. The topics investigated were Z' -> ll, Higgs -> ZZ* -. 4l, lepton flavor violation, muon compositeness, left-right symmetric theories, and a search for Higgs -> ee. The Brandeis group has for many years been a leader in the endcap muon system, making important contributions to every aspect of its design and production. During the past three years, the group continued to work on commissioning the muon detector and alignment system, development of alignment software, and installation of remaining chambers.

  15. The behavior of delaminations in composite materials - experimental results

    NASA Astrophysics Data System (ADS)

    Chermoshentseva, A. S.; Pokrovskiy, A. M.; Bokhoeva, L. A.

    2016-02-01

    Delamination is one of the most common failure modes of composite materials. It may occur as a consequence of imperfections in the production process or the effects of external factors during the operational life of the composite laminates, such as the impact by foreign objects. This paper presents the results of mechanical tests and the optimum degrees of filling the composite materials (CM) with hydrophobic powder (Tarkosil T-20) depending on the latter mass concentration. The results present test samples of the CM with the underlying interlayer defects. The samples were fabricated of twenty-ply pre-preg (fiberglass or carbon fiber). The industrial grade glass is T-25 (VM) specification 6-11-380-76. The composite materials have nanosized additives in structure. The volume concentration of nanopowders is varying from 0.1% to 0.5%. This kind of research has been done for the first time.

  16. Design and Experimental Results for the S407 Airfoil

    DTIC Science & Technology

    2010-08-01

    the drag coefficient within the laminar bucket is nearly constant. (See, for example, ref. 7.) This characteristic is related to the elimination of...with increasing (or decreasing) lift coefficient. This feature results in a leading edge that produces a suction peak at higher lift coefficients, which...distribution should look like sketch 3. Sketch 3 No suction spike exists at the leading edge. Instead, a rounded peak occurs aft of the leading edge, which

  17. Delaminations in composite plates under transverse static loads - Experimental results

    NASA Technical Reports Server (NTRS)

    Finn, Scott R.; He, Yi-Fei; Springer, George S.

    1992-01-01

    Tests were performed measuring the damage initiation loads and the locations, shapes, and sizes of delaminations in Fiberite T300/976 graphite/epoxy, Fiberite IM7/977-2 graphite-toughened epoxy, and ICI APC-2 graphite-PEEK plates subjected to transverse static loads. The data were compared to the results of the Finn-Springer model, and good agreements were found between the measured and calculated delamination lengths and widths.

  18. Quark gluon plasma: Overview and experimental results from E-735

    SciTech Connect

    Turkot, F.; Alexopoulos, T.; Allen, C.; Anderson, E.W.; Areti, H.; Banerjee, S.; Beery, P.D.; Biswas, N.N.; Bujak, A.; Carmony, D.D.

    1988-12-14

    A brief review of the phenomenology associated with the effort to produce and observe quark-gluon plasma in particle collisions is presented. E-735 has taken data during the 1987 Tevatron-Collider run at /square root/s = 1.8 TeV in pursuit of this goal. Results in the correlation of < p/sub t/ > with multiplicity for charged particles and p/sub t/ distributions for ..lambda../sup o/ and /bar Lambda//sup o/ are presented. 32 refs., 10 figs., 2 tabs.

  19. Experimental results of a propeller/wing interaction study

    NASA Technical Reports Server (NTRS)

    Johnson, Robert T.; Sullivan, John P.; Witkowski, David P.

    1991-01-01

    Steady state measurements have been performed on a propellar and a wing in a tractor configuration, to investigate the consequences of mutual interference on overall performance. For certain geometries wing lift is found to be enhanced, and wing drag to be decreased. The unsteady nature of the propeller-wing aerodynamic interaction has been studied using flow visualization. Results obtained indicate that the tip vortex is severed at the wing leading edge, the severed tip vortex filaments shear in a spanwise direction relative to one another, and these displaced filaments deform to reconnect at the trailing edge.

  20. Delaminations in composite plates under transverse impact loads - Experimental results

    NASA Technical Reports Server (NTRS)

    Finn, Scott R.; He, Ye-Fei; Springer, George S.

    1993-01-01

    Tests were performed measuring the locations and geometries of delaminations in Fiberite T300/976 graphite/epoxy, Fiberite IM7/977-2 graphite-toughened epoxy, and ICI APC-2 graphite/PEEK plates subjected to transverse impact loads. The data provide specific information on the effects of impactor velocity, impactor mass, material, thickness of back ply group, difference in fiber orientation between adjacent ply groups, plate thickness, and impactor nose radius. The data were compared to the results of the Finn-Springer model. The model was found to describe the data with reasonable accuracy.

  1. Parallel and Distributed Computational Fluid Dynamics: Experimental Results and Challenges

    NASA Technical Reports Server (NTRS)

    Djomehri, Mohammad Jahed; Biswas, R.; VanderWijngaart, R.; Yarrow, M.

    2000-01-01

    This paper describes several results of parallel and distributed computing using a large scale production flow solver program. A coarse grained parallelization based on clustering of discretization grids combined with partitioning of large grids for load balancing is presented. An assessment is given of its performance on distributed and distributed-shared memory platforms using large scale scientific problems. An experiment with this solver, adapted to a Wide Area Network execution environment is presented. We also give a comparative performance assessment of computation and communication times on both the tightly and loosely-coupled machines.

  2. Experimental test accelerator: description and results of initial experiments

    SciTech Connect

    Fessenden, T.; Birx, D.; Briggs, R.

    1980-06-02

    The ETA is a high current (10,000 Amp) linear induction accelerator that produces short (30 ns) pulses of electrons at 5 MeV twice per second or in bursts of 5 pulses separated by as little as one millisecond. At this time the machine has operated at 65% of its design current and 90% of the design voltage. This report contains a description of the accelerator and its diagnostics; the results of the initial year of operation; a comparison of design codes with experiments on beam transport; and a discussion of some of the special problems and their status.

  3. Experimental study of energy harvesting in UHF band

    NASA Astrophysics Data System (ADS)

    Bernacki, Ł.; Gozdur, R.; Salamon, N.

    2016-04-01

    A huge progress of down-sizing technology together with trend of decreasing power consumption and, on the other hand, increasing efficiency of electronics give the opportunity to design and to implement the energy harvesters as main power sources. This paper refers to the energy that can be harvested from electromagnetic field in the unlicensed frequency bands. The paper contains description of the most popular techniques and transducers that can be applied in energy harvesting domain. The overview of current research and commercial solutions was performed for bands in ultra-high frequency range, which are unlicensed and where transmission is not limited by administrative arrangements. During the experiments with Powercast’s receiver, the same bands as sources of electromagnetic field were taken into account. This power source is used for conducting radio-communication process and excess energy could be used for powering the extra electronic circuits. The paper presents elaborated prototype of energy harvesting system and the measurements of power harvested in ultra-high frequency range. The evaluation of RF energy harvesters for powering ultra-low power (ULP) electronic devices was performed based on survey and results of the experiments.

  4. Space Launch System Base Heating Test: Experimental Operations & Results

    NASA Technical Reports Server (NTRS)

    Dufrene, Aaron; Mehta, Manish; MacLean, Matthew; Seaford, Mark; Holden, Michael

    2016-01-01

    NASA's Space Launch System (SLS) uses four clustered liquid rocket engines along with two solid rocket boosters. The interaction between all six rocket exhaust plumes will produce a complex and severe thermal environment in the base of the vehicle. This work focuses on a recent 2% scale, hot-fire SLS base heating test. These base heating tests are short-duration tests executed with chamber pressures near the full-scale values with gaseous hydrogen/oxygen engines and RSRMV analogous solid propellant motors. The LENS II shock tunnel/Ludwieg tube tunnel was used at or near flight duplicated conditions up to Mach 5. Model development was based on the Space Shuttle base heating tests with several improvements including doubling of the maximum chamber pressures and duplication of freestream conditions. Test methodology and conditions are presented, and base heating results from 76 runs are reported in non-dimensional form. Regions of high heating are identified and comparisons of various configuration and conditions are highlighted. Base pressure and radiometer results are also reported.

  5. Microgravity Fluid Separation Physics: Experimental and Analytical Results

    NASA Technical Reports Server (NTRS)

    Shoemaker, J. Michael; Schrage, Dean S.

    1997-01-01

    Effective, low power, two-phase separation systems are vital for the cost-effective study and utilization of two-phase flow systems and flow physics of two-phase flows. The study of microgravity flows have the potential to reveal significant insight into the controlling mechanisms for the behavior of flows in both normal and reduced gravity environments. The microgravity environment results in a reduction in gravity induced buoyancy forces acting on the discrete phases. Thus, surface tension, viscous, and inertial forces exert an increased influence on the behavior of the flow as demonstrated by the axisymmetric flow patterns. Several space technology and operations groups have studied the flow behavior in reduced gravity since gas-liquid flows are encountered in several systems such as cabin humidity control, wastewater treatment, thermal management, and Rankine power systems.

  6. M-I-S solar cell - Theory and experimental results

    NASA Technical Reports Server (NTRS)

    Childs, R.; Fortuna, J.; Geneczko, J.; Fonash, S. J.

    1976-01-01

    The paper presents an operating-mode analysis of an MIS solar cell and discusses the advantages which can arise as a result of the use of transport control, field shaping (increased n factor), and zero bias barrier height modification. It is noted that for an n-type semiconductor, it is relatively easy to obtain an enhanced n factor using acceptor-like states without an increase in diode saturation current, the converse being true for p-type semiconductors. Several MIS configurations are examined: an acceptor-like, localized state configuration producing field shaping and no change in diode saturation current, and acceptor-like localized configurations producing field shaping, with a decrease of diode saturation current, in one case, and an increase in the other.

  7. Numerical Simulation of Micronozzles with Comparison to Experimental Results

    NASA Astrophysics Data System (ADS)

    Thornber, B.; Chesta, E.; Gloth, O.; Brandt, R.; Schwane, R.; Perigo, D.; Smith, P.

    2004-10-01

    A numerical analysis of conical micronozzle flows has been conducted using the commercial software package CFD-RC FASTRAN [13]. The numerical results have been validated by comparison with direct thrust and mass flow measurements recently performed in ESTEC Propulsion Laboratory on Polyflex Space Ltd. 10mN Cold-Gas thrusters in the frame of ESA CryoSat mission. The flow is viscous dominated, with a throat Reynolds number of 5000, and the relatively large length of the nozzle causes boundary layer effects larger than usual for nozzles of this size. This paper discusses in detail the flow physics such as boundary layer growth and structure, and the effects of rarefaction. Furthermore a number of different domain sizes and exit boundary conditions are used to determine the optimum combination of computational time and accuracy.

  8. New experimental results in atlas-based brain morphometry

    NASA Astrophysics Data System (ADS)

    Gee, James C.; Fabella, Brian A.; Fernandes, Siddharth E.; Turetsky, Bruce I.; Gur, Ruben C.; Gur, Raquel E.

    1999-05-01

    In a previous meeting, we described a computational approach to MRI morphometry, in which a spatial warp mapping a reference or atlas image into anatomic alignment with the subject is first inferred. Shape differences with respect to the atlas are then studied by calculating the pointwise Jacobian determinant for the warp, which provides a measure of the change in differential volume about a point in the reference as it transforms to its corresponding position in the subject. In this paper, the method is used to analyze sex differences in the shape and size of the corpus callosum in an ongoing study of a large population of normal controls. The preliminary results of the current analysis support findings in the literature that have observed the splenium to be larger in females than in males.

  9. Shear Faulting and Adiabatic Heating: Experimental Results from Ice

    NASA Astrophysics Data System (ADS)

    Golding, N.; Schulson, E. M.; Renshaw, C. E.

    2011-12-01

    Ice exhibits two distinct modes of shear faulting (Golding et al. Acta Materialia, 2010;58:5043), namely frictional or Coulombic (C) faulting under moderate levels of confinement and non-frictional or plastic (P) faulting under high levels of confinement. The mechanisms governing C-faulting have previously been discussed in connection with the comb-crack model (Renshaw & Schulson Nature, 2001;412:897). Here we examine the physical process[es] that trigger P-faulting. Systematic experiments on laboratory grown granular and columnar polycrystalline ice loaded triaxially under a high degree of confinement at -10 oC to -40 oC at applied strain rates 10-5 s-1 to 10-1 s-1 trace the micro-mechanical evolution of P-faulting. Terminal failure is characterized by a sudden brittle-like loss in load bearing capacity, the development of a narrow shear band, comprised of recrystallized grains and oriented on a plane of maximum shear, and localized heating. Possible mechanisms considered to account for the localization include: 1) adiabatic heating, 2) localized material softening through a reduction in dislocation density caused by dynamic recrystallization and 3) a transition from power-law creep to grain-size-dependent diffusional creep as a result of grain refinement caused by dynamic recrystallization. Our results indicate that, although recrystallization develops dynamically during loading, microstructural development does not significantly affect shear localization in ice. Nor does it affect the character of the fault. The minimum levels of deformation required to generate faulting are found to be consistent with those predicted for adiabatic shear instability. The present observations suggest that under specific conditions adiabatic heating, rather than dynamic recrystallization, may lead to material instability and shear faulting.

  10. Experimental results: Pilot plant calcine dissolution and liquid feed stability

    SciTech Connect

    Herbst, R.S.; Fryer, D.S.; Brewer, K.N.; Johnson, C.K.; Todd, T.A.

    1995-02-01

    The dissolution of simulated Idaho Chemical Processing Plant pilot plant calcines, containing none of the radioactive actinides, lanthanides or fission products, was examined to evaluate the solubility of calcine matrix materials in acidic media. This study was a necessary precursor to dissolution and optimization experiments with actual radionuclide-containing calcines. The importance of temperature, nitric acid concentration, ratio of acid volume to calcine mass, and time on the amount, as a weight percentage of calcine dissolved, was evaluated. These parameters were studied for several representative pilot plant calcine types: (1) Run No. 74 Zirconia calcine; (2) Run No. 17 Zirconia/Sodium calcine; (3) Run No. 64 Zirconia/Sodium calcine; (3) Run No. 1027 Alumina calcine; and (4) Run No. 20 Alumina/Zirconia/Sodium calcine. Statistically designed experiments with the different pilot plant calcines indicated the effect of the studied process variables on the amount of calcine dissolved decreases in the order: Acid/Calcine Ratio > Temperature > HNO{sub 3} Concentration > Dissolution Time. The following conditions are suitable to achieve greater than 90 wt. % dissolution of most Zr, Al, or Na blend calcines: (1) Maximum nitric acid concentration of 5M; (2) Minimum acid/calcine ratio of 10 mL acid/1 gram calcine; (3) Minimum dissolution temperature of 90{degrees}C; and (4) Minimum dissolution time of 30 minutes. The formation of calcium sulphate (CaSO{sub 4}) precipitates was observed in certain dissolved calcine solutions during the dissolution experiments. Consequently, a study was initiated to evaluate if and under what conditions the resulting dissolved calcine solutions would be unstable with regards to precipitate formation. The results indicate that precipitate formation in the calcine solutions prepared under the above proposed dissolution conditions are not anticipated.

  11. Longitudinal variation of the equatorial ionosphere: Modeling and experimental results

    NASA Astrophysics Data System (ADS)

    Souza, J. R.; Asevedo, W. D.; dos Santos, P. C. P.; Petry, A.; Bailey, G. J.; Batista, I. S.; Abdu, M. A.

    2013-02-01

    We describe a new version of the Parameterized Regional Ionospheric Model (PARIM) which has been modified to include the longitudinal dependences. This model has been reconstructed using multidimensional Fourier series. To validate PARIM results, the South America maps of critical frequencies for the E (foE) and F (foF2) regions were compared with the values calculated by Sheffield Plasmasphere-Ionosphere Model (SUPIM) and IRI representations. PARIM presents very good results, the general characteristics of both regions, mainly the presence of the equatorial ionization anomaly, were well reproduced for equinoctial conditions of solar minimum and maximum. The values of foF2 and hmF2 recorded over Jicamarca (12°S; 77°W; dip lat. 1°N; mag. declination 0.3°) and sites of the conjugate point equatorial experiment (COPEX) campaign Boa Vista (2.8°N; 60.7°W; dip lat. 11.4°; mag. declination -13.1°), Cachimbo (9.5°S; 54.8°W; dip lat. -1.8°; mag. declination -15.5°), and Campo Grande (20.4°S; 54.6°W; dip lat. -11.1°; mag. declination -14.0°) have been used in this work. foF2 calculated by PARIM show good agreement with the observations, except during morning over Boa Vista and midnight-morning over Campo Grande. Some discrepancies were also found for the F-region peak height (hmF2) near the geomagnetic equator during times of F3 layer occurrences. IRI has underestimated both foF2 and hmF2 over equatorial and low latitude sectors during evening-nighttimes, except for Jicamarca where foF2 values were overestimated.

  12. Epidural application of ionomeric cement implants. Experimental and clinical results.

    PubMed

    Geyer, G; Baier, G; Helms, J

    1998-04-01

    During setting and hardening, the hybrid bone substitute ionomeric cement (Ionocem) achieves a stable and durable bond with the apatite of the adjacent bone without interpository soft tissue. Fluid contact during setting results in the release of aluminium ions which may reach critical levels as high as 3000 micrograms/l. On epidural application it is, therefore, essential to prevent cement constituents from gaining access to the intradural space. After the cement has hardened, the presence of aluminium is demonstrable in the adjacent bone to a maximum depth of 20 microns (EDX microanalysis). In rabbits, epidural placement of freshly mixed cement causes slight thickening of the dura. There is reason to believe that human dura, with a thickness 10 times greater, is impermeable to components of the cement. After epidural application of the freshly mixed cement in the frontobasal and laterobasal regions and at the skull cap and petrous apex, 76 patients in all have been followed for up to 6.5 years. During this period no complications have arisen and functional (and cosmetic) results are promising. The availability of preformed implants (Ionoroc, Ionocast) permitted the peridural placement of minimal quantities of freshly mixed cement. These implants were fixed to localized sites on the adjacent calvarial bone by use of Ionocem. Notwithstanding the stringent manufacturer guidelines, there have been reports in the literature that during the vulnerable stage of setting neurotoxic aluminium ions were released into the dural space with a fatal outcome in two cases. In view of potential intradural complications, such as may occur in case of dural leaks, it was considered that further application of the material adjacent to the dura was no longer warranted. The production of Ionocem was discontinued in May 1995.

  13. Results from an energy-efficient showerhead field study

    SciTech Connect

    Warwick, W.M.; Bailey, S.A.

    1993-06-01

    In 1991 the Bonneville Power Administration (Bonneville) initiated research to determine the energy savings potential of energy-efficient showerheads, including a two-phase study by Pacific Northwest Laboratory (PNL). The PNL study focused on 154 homes monitored with end-use metering equipment. In the first phase of the study, PNL recruited participants from the homes, installed energy efficient showerheads, and collected occupant and site characteristics data. The second phase of the study is an analysis of the end-use load data to estimate energy use and savings from showerheads over a two-year period. This report presents the results from the first phase field study. Program results are based on the number of homes that participated in various aspects of the study. Among the 154 of homes selected for the study, 65% agreed to participate. Eighty-eight percent of these homes actually had their showerheads replaced. After 15 months, 94% of the homes where showerheads were installed still had at least one in place. Measure results are based on the number of showerheads that were installed. The 154 homes contained an estimated 240 showerheads that could have been replaced. Sixty-six percent of these showerheads were actually replaced. If only showers in participant homes are considered, 83% of the showerheads were replaced. Measure persistence at the end of 15 months was 94%. The water flow rate from existing showerheads averaged 3.2 gallons per minute (gpm) at participating sites. Average water pressure for city-supplied water was 66 pounds per square inch (psi). Water pressure at homes on wells was over 40% lower, which reduced savings potential. The energy-efficient showerheads had an average flow rate of 1.8 gpm. Observed water flow reductions of 1.4 gpm were obtained from retrofit of energy-efficient showerheads. In about 20% of the showers, water flows remained constant or actually increased after retrofit of energy-efficient showerheads.

  14. [Restoring fertility with frozen ovarian tissue; experimental results].

    PubMed

    Salle, Runo; Lornage, Jacqueline

    2013-01-01

    In recent decades, reproductive surgery and medicine have entered a new era of prevention. Oocyte freezing is at the heart of this new era, along with the preservation offemale fertility. Several options are being evaluated, and time will tell which one will prove most suitable for routine use. Currently, only the freezing and transplantation of ovarian tissue seems to have entered clinical practice. Animal studies demonstrated its effectiveness, with pregnancies and births in several species. These studies showed that both slow and rapid freezing (vitrification) allows the survival of more than 80 % of primordial follicles after thawing. Similar results have since been obtained in humans. Freezing allows satisfactory follicular survival Reimplantation of frozen ovarian tissue has helped to restore menstrual cycling and, more importantly, to obtain pregnancies and births, either spontaneously or by IVF This restoration of fertility offers great hopefor female patients having to confront not only their disease but also the prospect of permanent infertility. Related research has led to major advances in biology and reproductive medicine.

  15. Impact ejecta dynamics in an atmosphere - Experimental results and extrapolations

    NASA Technical Reports Server (NTRS)

    Schultz, P. H.; Gault, D. E.

    1982-01-01

    It is noted that the impacts of 0.635-cm aluminum projectiles at 6 km/sec into fine pumice dust, at 1 atm, generate a ball of ionized gas behind an expanding curtain of upward moving ejecta. The gas ball forms a toroid which dissolves as it is driven along the interior of the ejecta curtain, by contrast to near-surface explosions in which a fireball envelops early-time crater growth. High frame rate Schlieren photographs show that the atmosphere at the base of the ejecta curtain is initially turbulent, but later forms a vortex. These experiments suggest that although small size ejecta may be decelerated by air drag, they are not simply lofted and suspended but become incorporated in an ejecta cloud that is controlled by air flow which is produced by the response of the atmosphere to the impact. The extrapolation of these results to large body impacts on the earth suggests such contrasts with laboratory experiments as a large quantity of impact-generated vapor, the supersonic advance of the ejecta curtain, the lessened effect of air drag due to the tenuous upper atmosphere, and the role of secondary cratering.

  16. Bridge Testing With Ground-Based Interferometric Radar: Experimental Results

    SciTech Connect

    Chiara, P.; Morelli, A.

    2010-05-28

    The research of innovative non-contact techniques aimed at the vibration measurement of civil engineering structures (also for damage detection and structural health monitoring) is continuously directed to the optimization of measures and methods. Ground-Based Radar Interferometry (GBRI) represents the more recent technique available for static and dynamic control of structures and ground movements.Dynamic testing of bridges and buildings in operational conditions are currently performed: (a) to assess the conformity of the structure to the project design at the end of construction; (b) to identify the modal parameters (i.e. natural frequencies, mode shapes and damping ratios) and to check the variation of any modal parameters over the years; (c) to evaluate the amplitude of the structural response to special load conditions (i.e. strong winds, earthquakes, heavy railway or roadway loads). If such tests are carried out by using a non-contact technique (like GBRI), the classical issues of contact sensors (like accelerometers) are easily overtaken.This paper presents and discusses the results of various tests carried out on full-scale bridges by using a Stepped Frequency-Continuous Wave radar system.

  17. Overview of experimental results on the HL-2A tokamak

    NASA Astrophysics Data System (ADS)

    Yan, L. W.; Duan, X. R.; Ding, X. T.; Dong, J. Q.; Yang, Q. W.; Liu, Yi; Zou, X. L.; Liu, D. Q.; Xuan, W. M.; Chen, L. Y.; Rao, J.; Song, X. M.; Huang, Y.; Mao, W. C.; Wang, Q. M.; Li, Q.; Cao, Z.; Li, B.; Cao, J. Y.; Lei, G. J.; Zhang, J. H.; Li, X. D.; Chen, W.; Cheng, J.; Cui, C. H.; Cui, Z. Y.; Deng, Z. C.; Dong, Y. B.; Feng, B. B.; Gao, Q. D.; Han, X. Y.; Hong, W. Y.; Huang, M.; Ji, X. Q.; Kang, Z. H.; Kong, D. F.; Lan, T.; Li, G. S.; Li, H. J.; Li, Qing; Li, W.; Li, Y. G.; Liu, A. D.; Liu, Z. T.; Luo, C. W.; Mao, X. H.; Pan, Y. D.; Peng, J. F.; Shi, Z. B.; Song, S. D.; Song, X. Y.; Sun, H. J.; Wang, A. K.; Wang, M. X.; Wang, Y. Q.; Xiao, W. W.; Xie, Y. F.; Yao, L. H.; Yao, L. Y.; Yu, D. L.; Yuan, B. S.; Zhao, K. J.; Zhong, G. W.; Zhou, J.; Zhou, Y.; Yan, J. C.; Yu, C. X.; Pan, C. H.; Liu, Yong; HL-2A Team

    2011-09-01

    The physics experiments on the HL-2A tokamak have been focused on confinement improvement, particle and thermal transport, zonal flow and turbulence, filament characteristics, energetic particle induced modes and plasma fuelling efficiency since 2008. ELMy H-mode discharges are achieved in a lower density regime using a combination of NBI heating with ECRH. The power threshold is found to increase with a decrease in density, almost independent of the launching order of the ECRH and NBI heating power. The pedestal density profiles in the H-mode discharges are measured. The particle outward convection is observed during the pump-out transient phase with ECRH. The negative density perturbation (pump-out) is observed to propagate much faster than the positive one caused by out-gassing. The core electron thermal transport reduction triggered by far off-axis ECRH switch-off is investigated. The coexistence of low frequency zonal flow (LFZF) and geodesic acoustic mode (GAM) is observed. The dependence of the intensities of LFZFs and GAMs on the safety factor and ECRH power is identified. The 3D spatial structures of plasma filaments are measured in the boundary plasma and large-scale structures along a magnetic field line analysed for the first time. The beta-induced Alfvén eigenmodes (BAEs), excited by large magnetic islands (m-BAE) and by energetic electrons (e-BAE), are observed. The results for the study of fuelling efficiency and penetration characteristics of supersonic molecular beam injection (SMBI) are described.

  18. The experimental results and analysis of a borehole radar prototype

    NASA Astrophysics Data System (ADS)

    Liu, Sixin; Wu, Junjun; Dong, Hang; Fu, Lei; Wang, Fei

    2012-04-01

    A prototype of borehole radar has been successfully tested in three sites for different purposes under a field condition. The objective of the prototype is providing an effective down-hole tool for detecting targets in deep boreholes situated in a relatively high conductivity area such as the metal ores. The first testing site is at a geothermal field. The fractures extending more than 20 m from the borehole are delineated by the borehole radar in the single-hole reflection mode. The second testing site is located in a jade mine for basement evaluation. The cross-hole measurement mode was used to detect the cavities made by previous unorganized mining activities. Several high-velocity anomalies were found in the velocity profile and presumably the targets of the mine shafts and tunnels. The third test site is located in a mineralized belt characterized by low resistivity less than 1000 Ohm m, the surface-borehole measurement was carried out and the data were processed with velocity tomography. The low-velocity zone corresponds to a mineralized zone from geological records. The three testing results proved the readiness of this borehole radar prototype for further deployment in more complicated and realistic field situations.

  19. First experimental results on the IShTAR testbed

    SciTech Connect

    D’Inca, R.; Jacquot, J.; Ochoukov, R.; Morgal, I.; Fünfgelder, H.; Faugel, H.; Crombe, K.; Louche, F.; Van Eester, D.; Heuraux, S.; Devaux, S.; Moritz, J.; Faudot, E.; Noterdaeme, J.-M.

    2015-12-10

    IShTAR (Ion cyclotron Sheath Test ARrangement) is a linear magnetized plasma test facility dedicated to the investigation of RF wave/plasma interaction [1] in the Ion Cyclotron Range of Frequencies (ICRF). It provides a better accessibility for the instrumentation than tokamaks while being representative of the neighboring region of the wave emitter. It is equipped with a magnetized plasma source (1 m long, 0.4 m diameter) powered by a helical antenna up to 3 kW at 11 MHz. We present the results of the first analysis of the plasma characteristics (plasma density, electron temperature) in function of the operating parameters (injected power, neutral pressure and magnetic field) as measured with fixed and movable Langmuir probes, spectrometer and cameras. The plasma is presently produced only by the helical antenna (no ICRF). We show that the plasma exists in three regime depending on the power level: the first two ones are stable and separated by a jump in density; a first spatial profile of the plasma density has been established for these modes; The third mode is unstable, characterized by strong oscillations of the plasma tube position.

  20. Infrared thermography for CFRP inspection: computational model and experimental results

    NASA Astrophysics Data System (ADS)

    Fernandes, Henrique C.; Zhang, Hai; Morioka, Karen; Ibarra-Castanedo, Clemente; López, Fernando; Maldague, Xavier P. V.; Tarpani, José R.

    2016-05-01

    Infrared Thermography (IRT) is a well-known Non-destructive Testing (NDT) technique. In the last decades, it has been widely applied in several fields including inspection of composite materials (CM), specially the fiber-reinforced polymer matrix ones. Consequently, it is important to develop and improve efficient NDT techniques to inspect and assess the quality of CM parts in order to warranty airworthiness and, at the same time, reduce costs of airline companies. In this paper, active IRT is used to inspect carbon fiber-reinforced polymer (CFRP) at laminate with artificial inserts (built-in sample) placed on different layers prior to the manufacture. Two optical active IRT are used. The first is pulsed thermography (PT) which is the most widely utilized IRT technique. The second is a line-scan thermography (LST) technique: a dynamic technique, which can be employed for the inspection of materials by heating a component, line-by-line, while acquiring a series of thermograms with an infrared camera. It is especially suitable for inspection of large parts as well as complex shaped parts. A computational model developed using COMSOL Multiphysics® was used in order to simulate the inspections. Sequences obtained from PT and LST were processed using principal component thermography (PCT) for comparison. Results showed that it is possible to detect insertions of different sizes at different depths using both PT and LST IRT techniques.

  1. EXPERIMENTAL RESULTS OF THE NEPHELINE PHASE III STUDY

    SciTech Connect

    Fox, K.; Edwards, T.

    2009-11-09

    This study is the third phase in a series of experiments designed to reduce conservatism in the model that predicts the formation of nepheline, a crystalline phase that can reduce the durability of high level waste glass. A Phase I study developed a series of glass compositions that were very durable while their nepheline discriminator values were well below the current nepheline discriminator limit of 0.62, where nepheline is predicted to crystallize upon slow cooling. A Phase II study selected glass compositions to identify any linear effects of composition on nepheline crystallization and that were restricted to regions that fell within the validation ranges of the Defense Waste Processing Facility (DWPF) Product Composition Control System (PCCS) models. However, it was not possible to identify any linear effects of composition on chemical durability performance for this set of study glasses. The results of the Phase II study alone were not sufficient to recommend modification of the current nepheline discriminator. It was recommended that the next series of experiments continue to focus not only on compositional regions where the PCCS models are considered applicable (i.e., the model validation ranges), but also be restricted to compositional regions where the only constraint limiting processing is the current nepheline discriminator. Two methods were used in selecting glasses for this Phase III nepheline study. The first was based on the relationship of the current nepheline discriminator model to the other DWPF PCCS models, and the second was based on theory of crystallization in mineral and glass melts. A series of 29 test glass compositions was selected for this study using a combination of the two approaches. The glasses were fabricated and characterized in the laboratory. After reviewing the data, the study glasses generally met the target compositions with little issue. Product Consistency Test results correlated well with the crystallization analyses in

  2. Experimental limit on the cosmic diffuse ultrahigh energy neutrino flux.

    PubMed

    Gorham, P W; Hebert, C L; Liewer, K M; Naudet, C J; Saltzberg, D; Williams, D

    2004-07-23

    We report results from 120 h of live time with the Goldstone lunar ultrahigh energy neutrino experiment (GLUE). The experiment searches for < or = 10 ns microwave pulses from the lunar regolith, appearing in coincidence at two large radio telescopes separated by 22 km and linked by optical fiber. Such pulses would arise from subsurface electromagnetic cascades induced by interactions of > or = 100 EeV (1 EeV = 10(18) eV neutrinos in the lunar regolith. No candidates are yet seen, and the implied limits constrain several current models for ultrahigh energy neutrino fluxes.

  3. Experimental evaluation of exhaust mixers for an Energy Efficient Engine

    NASA Technical Reports Server (NTRS)

    Kozlowski, H.; Kraft, G.

    1980-01-01

    Static scale model tests were conducted to evaluate exhaust system mixers for a high bypass ratio engine as part of the NASA sponsored Energy Efficient program. Gross thrust coefficients were measured for a series of mixer configurations which included variations in the number of mixer lobes, tailpipe length, mixer penetration, and length. All of these parameters have a significant impact on exhaust system performance. In addition, flow visualization pictures and pressure/temperature traverses were obtained for selected configurations. Parametric performance trends are discussed and the results considered relative to the Energy Efficient Engine program goals.

  4. Future directions in high energy electron-positron experimentation

    SciTech Connect

    Trilling, G.H.

    1988-09-01

    In this report, the possibilities of studying particle physics at the TeV scale with high energy electron-positron linear colliders are discussed. A status report on the SLC and the MARK II program is given to provide some insights on the feasibility of experiments at linear colliders. The technical issues in going from SLC to the development of TeV colliders are briefly discussed. Some of the elements of the e/sup +/e/sup -/ experimental environment which differentiate it from that in hadron colliders and give examples of processes particularly well suited to attack by e/sup +/e/sup -/ annihilation are summarized. Finally, some concluding remarks are given. 8 refs., 10 figs., 2 tabs.

  5. Numerical and experimental comparison of the energy transfer in a parametrically excited system

    NASA Astrophysics Data System (ADS)

    Fichtinger, Andreas; Ecker, Horst

    2016-09-01

    This study is based on experimental results obtained from a test rig for a 2-DOF vibrational system. The main feature of this test rig is an electromechanical actuator which enables the variation of a mechanical stiffness parameter. The vibrational system is excited by this device, resulting in a parametrically excited system. In this study, the test rig is operated such that an initial deflection is applied to the masses, but no external excitation acts on the system. The actuator coils are driven by a current following a harmonic function defined by amplitude and frequency. The latter defines the parametric excitation frequency (PEF). When the mechanical system performs free vibrations, the parametric excitation may initiate an energy transfer between the two vibrational modes of the system. This transfer depends primarily on the PEF. For certain values of the PEF only one of the vibrational modes is affected. At other frequencies both modes are influenced and a continuous intermodal energy transfer is observed. A numerical model for the test rig was established and allows a comparison of experimental and numerical results. The total system energy as well as the modal energies are calculated from the measured and from the simulated signals. Interesting experimental observations are reported concerning the transfer of energy, and are in good agreement with simulated results.

  6. Save Energy Now Assessments Results 2008 Summary Report

    SciTech Connect

    Wright, Anthony L; Martin, Michaela A; Nimbalkar, Sachin U; Quinn, James; Glatt, Ms. Sandy; Orthwein, Mr. Bill

    2010-09-01

    assessment process at the company's other facilities. Another important element of the Save Energy Now assessment process is the follow-up process used to identify how many of the recommended savings opportunities from individual assessments have been implemented in the industrial plants. Plant personnel involved with the Save Energy Now assessments are contacted 6 months, 12 months, and 24 months after individual assessments are completed to determine implementation results. A total of 260 Save Energy Now assessments were successfully completed in calendar year 2008. This means that a total of 718 assessments were completed in 2006, 2007, and 2008. As of July 2009, we have received a total of 239 summary reports from the ESAs that were conducted in year 2008. Hence, at the time that this report was prepared, 680 final assessment reports were completed (200 from year 2006, 241 from year 2007, and 239 from year 2008). The total identified potential cost savings from these 680 assessments is $1.1 billion per year, including natural gas savings of about 98 TBtu per year. These results, if fully implemented, could reduce CO{sub 2} emissions by about 8.9 million metric tons annually. When this report was prepared, data on implementation of recommended energy and cost savings measures from 488 Save Energy Now assessments were available. For these 488 plants, measures saving a total of $147 million per year have been implemented, measures that will save $169 million per year are in the process of being implemented, and plants are planning implementation of measures that will save another $239 million per year. The implemented recommendations are already achieving total CO{sub 2} reductions of about 1.8 million metric tons per year. This report provides a summary of the key results for the Save Energy Now assessments completed in 2008; details of the 6-month, 12-month, and 24-month implementation results obtained to date; and an evaluation of these implementation results. This

  7. Save Energy Now Assessments Results 2008 Detailed Report

    SciTech Connect

    Wright, Anthony L; Martin, Michaela A; Nimbalkar, Sachin U; Quinn, James; Glatt, Ms. Sandy; Orthwein, Mr. Bill

    2010-09-01

    assessment process at the company's other facilities. Another important element of the Save Energy Now assessment process is the follow-up process used to identify how many of the recommended savings opportunities from individual assessments have been implemented in the industrial plants. Plant personnel involved with the Save Energy Now assessments are contacted 6 months, 12 months, and 24 months after individual assessments are completed to determine implementation results. A total of 260 Save Energy Now assessments were successfully completed in calendar year 2008. This means that a total of 718 assessments were completed in 2006, 2007, and 2008. As of July 2009, we have received a total of 239 summary reports from the ESAs that were conducted in year 2008. Hence, at the time that this report was prepared, 680 final assessment reports were completed (200 from year 2006, 241 from year 2007, and 239 from year 2008). The total identified potential cost savings from these 680 assessments is $1.1 billion per year, including natural gas savings of about 98 TBtu per year. These results, if fully implemented, could reduce CO{sub 2} emissions by about 8.9 million metric tons annually. When this report was prepared, data on implementation of recommended energy and cost savings measures from 488 Save Energy Now assessments were available. For these 488 plants, measures saving a total of $147 million per year have been implemented, measures that will save $169 million per year are in the process of being implemented, and plants are planning implementation of measures that will save another $239 million per year. The implemented recommendations are already achieving total CO{sub 2} reductions of about 1.8 million metric tons per year. This report provides a summary of the key results for the Save Energy Now assessments completed in 2008; details of the 6-month, 12-month, and 24-month implementation results obtained to date; and an evaluation of these implementation results. This

  8. Assessing Internet energy intensity: A review of methods and results

    SciTech Connect

    Coroama, Vlad C.; Hilty, Lorenz M.

    2014-02-15

    Assessing the average energy intensity of Internet transmissions is a complex task that has been a controversial subject of discussion. Estimates published over the last decade diverge by up to four orders of magnitude — from 0.0064 kilowatt-hours per gigabyte (kWh/GB) to 136 kWh/GB. This article presents a review of the methodological approaches used so far in such assessments: i) top–down analyses based on estimates of the overall Internet energy consumption and the overall Internet traffic, whereby average energy intensity is calculated by dividing energy by traffic for a given period of time, ii) model-based approaches that model all components needed to sustain an amount of Internet traffic, and iii) bottom–up approaches based on case studies and generalization of the results. Our analysis of the existing studies shows that the large spread of results is mainly caused by two factors: a) the year of reference of the analysis, which has significant influence due to efficiency gains in electronic equipment, and b) whether end devices such as personal computers or servers are included within the system boundary or not. For an overall assessment of the energy needed to perform a specific task involving the Internet, it is necessary to account for the types of end devices needed for the task, while the energy needed for data transmission can be added based on a generic estimate of Internet energy intensity for a given year. Separating the Internet as a data transmission system from the end devices leads to more accurate models and to results that are more informative for decision makers, because end devices and the networking equipment of the Internet usually belong to different spheres of control. -- Highlights: • Assessments of the energy intensity of the Internet differ by a factor of 20,000. • We review top–down, model-based, and bottom–up estimates from literature. • Main divergence factors are the year studied and the inclusion of end devices

  9. Femtosecond pulse laser ablation of chromium: experimental results and two-temperature model simulations

    NASA Astrophysics Data System (ADS)

    Saghebfar, M.; Tehrani, M. K.; Darbani, S. M. R.; Majd, A. E.

    2017-01-01

    In this work, the results of experimental and computational single- and multi-shot ablation threshold and the incubation effect of chromium metal sample, irradiated by ultrashort laser pulses, are presented. The experimental value of the ablation threshold is determined based on D2 method by measuring the outer ablation crater diameters as a function of incident laser pulse energy using 800 nm, 30 fs, laser pulses. The value of 0.19 ± 0.04 (J/cm2 ), is obtained for the single-shot ablation threshold fluence. The experimental results are compared with time-dependent heat flow calculations based on the two-temperature model and the effect of number and separation time of two consecutive laser pulses with the same total fluence is studied for the Cr target. Moreover, the role of pulse width and absorbed fluence in thermal equilibrium time between electrons and lattice is investigated in two-temperature model. The thermal equilibrium between electron and lattice is established after a few picoseconds for low fluences and after a few tens of picoseconds at higher fluences.

  10. Molecular modeling of hair keratin/peptide complex: Using MM-PBSA calculations to describe experimental binding results.

    PubMed

    Azoia, Nuno G; Fernandes, Margarida M; Micaêlo, Nuno M; Soares, Cláudio M; Cavaco-Paulo, Artur

    2012-05-01

    Molecular dynamics simulations of a keratin/peptide complex have been conducted to predict the binding affinity of four different peptides toward human hair. Free energy calculations on the peptides' interaction with the keratin model demonstrated that electrostatic interactions are believed to be the main driving force stabilizing the complex. The molecular mechanics-Poisson-Boltzmann surface area methodology used for the free energy calculations demonstrated that the dielectric constant in the protein's interior plays a major role in the free energy calculations, and the only way to obtain accordance between the free energy calculations and the experimental binding results was to use the average dielectric constant.

  11. Experimental analysis of Hybridised Energy Storage Systems for automotive applications

    NASA Astrophysics Data System (ADS)

    Sarwar, Wasim; Engstrom, Timothy; Marinescu, Monica; Green, Nick; Taylor, Nigel; Offer, Gregory J.

    2016-08-01

    The requirements of the Energy Storage System (ESS) for an electrified vehicle portfolio consisting of a range of vehicles from micro Hybrid Electric Vehicle (mHEV) to a Battery Electric Vehicle (BEV) vary considerably. To reduce development cost of an electrified powertrain portfolio, a modular system would ideally be scaled across each vehicle; however, the conflicting requirements of a mHEV and BEV prevent this. This study investigates whether it is possible to combine supercapacitors suitable for an mHEV with high-energy batteries suitable for use in a BEV to create a Hybridised Energy Storage System (HESS) suitable for use in a HEV. A passive HESS is found to be capable of meeting the electrical demands of a HEV drive cycle; the operating principles of HESSs are discussed and factors limiting system performance are explored. The performance of the HESS is found to be significantly less temperature dependent than battery-only systems, however the heat generated suggests a requirement for thermal management. As the HESS degrades (at a similar rate to a specialised high-power-battery), battery resistance rises faster than supercapacitor resistance; as a result, the supercapacitor provides a greater current contribution, therefore the energy throughput, temperature rise and degradation of the batteries is reduced.

  12. First experimentally determined thermodynamic values of francium: hydration energy, energy of partitioning, and thermodynamic radius.

    PubMed

    Delmau, Lætitia H; Moine, Jérôme; Mirzadeh, Saed; Moyer, Bruce A

    2013-08-08

    The Gibbs energy of partitioning of Fr(+) ion between water and nitrobenzene has been determined to be 14.5 ± 0.6 kJ/mol at 25 °C, the first ever Gibbs energy of partitioning for francium in particular and the first ever solution thermodynamic quantity for francium in general. This value enabled the ionic radius and standard Gibbs energy of hydration for Fr(+) to be estimated as 173 pm and -251 kJ/mol, respectively, the former value being significantly smaller than previously thought. A new experimental method was established using a cesium dicarbollide as a cation-exchange agent, overcoming problems inherent to the trace-level concentrations of francium. The methodology opens the door to the study of the partitioning behavior of francium to other water-immiscible solvents and the determination of complexation constants for francium binding by receptor molecules.

  13. Preliminary experimental results of tungsten wire-array Z-pinches on primary test stand

    SciTech Connect

    Huang, Xian-Bin; Zhou, Shao-Tong; Dan, Jia-Kun; Ren, Xiao-Dong Wang, Kun-Lun; Zhang, Si-Qun; Li, Jing; Xu, Qiang; Cai, Hong-Chun; Duan, Shu-Chao; Ouyang, Kai; Chen, Guang-Hua; Ji, Ce; Wei, Bing; Feng, Shu-Ping; Wang, Meng; Xie, Wei-Ping; Deng, Jian-Jun; Zhou, Xiu-Wen; Yang, Yi

    2015-07-15

    The Primary Test Stand (PTS) developed at the China Academy of Engineering Physics is a 20 TW pulsed power driver, which can deliver a ∼10 MA, 70 ns rise-time (10%–90%) current to a short-circuit load and has important applications in Z-pinch driven inertial confinement fusion and high energy density physics. Preliminary results of tungsten wire-array Z-pinch experiments on PTS are presented. The load geometries investigated include 15-mm-tall cylindrical single and nested arrays with diameter ranging from 13 mm to 30 mm, consisting of 132–300 tungsten wires with 5–10 μm in diameter. Multiple diagnostics were fielded to characterize the x-ray radiation from wire-array Z pinches. The x-ray peak power (∼50 TW) and total radiated energy (∼500 kJ) were obtained from a single 20-mm-diam array with 80-ns stagnation time. The highest x-ray peak power up to 80 TW with 2.4 ns FWHM was achieved by using a nested array with 20-mm outer diameter, and the total x-ray energy from the nested array is comparable to that of single array. Implosion velocity estimated from the time-resolved image measurement exceeds 30 cm/μs. The detailed experimental results and other findings are presented and discussed.

  14. Experimental investigation of the energy and temperature dependence of beryllium self sputtering

    SciTech Connect

    Korshunov, S.N.; Guseva, M.I.; Stolijarova, V.G.

    1995-09-01

    The low-Z metal beryllium is considered as plasma facing material (PFM) for the ITER. It is expected that operation temperature range of beryllium PFM will be (670 - 1070) K. While experimental Be-sputtering data bases exist for H{sup +}, D{sup +} and He{sup +}-ions, the self-sputtering yields of Be have only been estimated by computer simulation. In this paper we report the experimental results on the energy and temperature dependence of the beryllium self-sputtering yield (S). The energy dependence of S{sup s} in the energy range (0.5 - 10.0) keV was measured at 670 K. The self-sputtering yield of Be attains its maximal value at the ion energy of 1.5 keV, being equal to 0.32 {+-} at./ion. Comparison of the experimental results and theoretical prediction shows a good agreement for energy dependence of S{sup s}. The temperature dependence of S{sup s} in the temperature range (370-1070)K was obtained for 0.9keV Be{sup +}-ions. The value of S{sup s} is not changed up to 870 K. It sharply increases at the temperatures above 870 attaining the value of 0.75 at./ion at 1070 K.

  15. Sustain: An experimental test bed for building energy simulation

    SciTech Connect

    Greenberg, Donald; Pratt, Kevin; Hencey, Brandon; Jones, Nathaniel; Schumann, Lars; Dobbs, Justin; Dong, Zhao; Bosworth, David; Walter, Bruce

    2013-03-01

    Current building energy simulation technology requires extensive labor, time and expertise to create building energy models, substantial computational time for accurate simulations, and generates data in formats that make results difficult to interpret. These deficiencies can be ameliorated using modern graphical user interfaces and algorithms which take advantage of modern computer architectures and display capabilities. This paper describes a novel test bed environment which offers an interactive graphical interface, provides access to simulation modules that run at accelerated computational speeds, and presents new graphic visualization methods for the interpretation of simulation results. Its modular structure makes it suitable for use in early stage building design, for use as a research platform for the investigation of new simulation methods, and for use as a tool for teaching concepts of sustainable design. Improvements in the accuracy and execution speed of many of the simulation modules are based on the modification of advanced computer graphics rendering algorithms. Significant performance improvements are illustrated in several computationally expensive energy simulation modules.

  16. A Computational Model for Predicting Experimental RNA Nearest-Neighbor Free Energy Rankings: Inosine•Uridine Pairs.

    PubMed

    Jolley, Elizabeth A; Lewis, Michael; Znosko, Brent M

    2015-10-16

    A computational model for predicting RNA nearest neighbor free energy rankings has been expanded to include the nonstandard nucleotide inosine. The model uses average fiber diffraction data and molecular dynamic simulations to generate input geometries for Quantum mechanic calculations. This resulted in calculated intrastrand stacking, interstrand stacking, and hydrogen bonding energies that were combined to give total binding energies. Total binding energies for RNA dimer duplexes containing inosine were ranked and compared to experimentally determined free energy ranks for RNA duplexes containing inosine. Statistical analysis showed significant agreement between the computationally determined ranks and the experimentally determined ranks.

  17. Experimental and Statistical Evaluation of Cutting Methods in Relation to Specific Energy and Rock Properties

    NASA Astrophysics Data System (ADS)

    Engin, Irfan Celal; Bayram, Fatih; Yasitli, Nazmi Erhan

    2013-07-01

    In a processing plant, natural stone can be cut by methods such as circular sawing (CS), frame sawing (FS), water jet cutting (WJC) and abrasive water jet cutting (AWJC). The efficiency of cutting systems can be compared using various parameters. In this study, the specific energy values were determined and compared to evaluate the efficiency of rock-cutting methods. Rock-cutting experiments were performed on 12 different types of rock samples using a circular sawing machine and an AWJC machine. The experimental results showed that the specific energy values in AWJC were generally higher than in CS. In addition, the relationships between specific energy values and rock properties were explained in this study. The Shore hardness and abrasion resistance were found to be strongly related to the specific energy values, and according to these parameters prediction charts of specific energy values were created.

  18. Select Results from the Energy Assessor Experiment in the 2012 Commercial Buildings Energy Consumption Survey

    EIA Publications

    2015-01-01

    As part of an effort to make EIA’s energy consumption surveys as accurate and efficient as possible, EIA invited the National Research Council (NRC) to review the Commercial Buildings Energy Consumption Survey (CBECS) data-gathering process and make recommendations for improvements. The NRC suggested sending professional energy assessors to some sites and comparing the data obtained from the survey to the data collected by the assessors. Results from the energy assessment data collection have largely confirmed the quality of data gathered by CBECS interviewers.

  19. Experimental study of breaking and energy dissipation in surface waves

    NASA Astrophysics Data System (ADS)

    Ruiz Chavarria, Gerardo; Le Gal, Patrice; Le Bars, Michael

    2014-11-01

    We present an experimental study of the evolution of monochromatic waves produced by a parabolic wave maker. Because of the parabolic shape of the wave front, the waves exhibit spatial focusing and their amplitude dramatically increases over distances of a few wavelengths. Unlike linear waves, the amplitude of the free surface deformation cannot exceed a certain threshold and when this happens the waves break. In order to give a criterion for the appearance of breaking, we calculate the steepness defined as ɛ = H/ λ (where H is the wave height and λ their wavelength) for waves of frequencies in the range 4-10 Hz. We found that wave breaking develops when ɛ attains approximately a value of 0.10. We also evaluate the lost of energy carried by the waves during their breaking by a detailed and accurate measurement of their amplitude using an optical Fourier transform profilometry. G. Ruiz Chavarria acknowledges DGAPA-UNAM by support under Project IN 116312 (Vorticidad y ondas no lineales en fluidos).

  20. Experimental study on temperature characteristics and energy conversion in packed bed reactor with dielectric barrier discharge

    NASA Astrophysics Data System (ADS)

    Li, Sen; Tang, Zuchen; Gu, Fan

    2010-10-01

    The temperature characteristics and energy conversion in packed bed reactor combined with a dielectric barrier discharge (DBD) plasma was investigated experimentally. The pellet temperatures of two types packed bed reactor, cylindrical reactor and parallel-plate reactor, was measured in conditions of various inlet voltage of DBD plasma. The relationship between pellet temperature of the packed bed and applied voltage of DBD plasma was discovered. The experimental result indicates a tendency that the pellet temperature of packed bed increases as the applied voltage of inlet plasma increases. When the voltage of inlet plasma is high enough, the pellet temperature increment decreases. Simultaneously,the packed bed temperature is sensitive to the inlet plasma energy and there is a potential application to heat exchanger. Moreover the proportion of energy consumption of plasma inputting into packed bed reactor was analyzed and calculated. The mechanisms that electrical energy of inlet plasma is transformed into heat energy in the two phases, gaseous and pellets of the packed bed reactor are different. The energy consumption in pellet phase is dielectric polarization loss and depends on packed bed geometry and DBD plasma etc. The energy consumption in gaseous phase is plasma sheath procedure. The important factors effecting on gas discharge are gaseous component and voltage, frequency of power.

  1. High-energy radiation damage in zirconia: Modeling results

    SciTech Connect

    Zarkadoula, E.; Devanathan, R.; Weber, W. J.; Seaton, M. A.; Todorov, I. T.; Nordlund, K.; Dove, M. T.; Trachenko, K.

    2014-02-28

    Zirconia is viewed as a material of exceptional resistance to amorphization by radiation damage, and consequently proposed as a candidate to immobilize nuclear waste and serve as an inert nuclear fuel matrix. Here, we perform molecular dynamics simulations of radiation damage in zirconia in the range of 0.1–0.5 MeV energies with account of electronic energy losses. We find that the lack of amorphizability co-exists with a large number of point defects and their clusters. These, importantly, are largely isolated from each other and therefore represent a dilute damage that does not result in the loss of long-range structural coherence and amorphization. We document the nature of these defects in detail, including their sizes, distribution, and morphology, and discuss practical implications of using zirconia in intense radiation environments.

  2. High-energy radiation damage in zirconia: modeling results

    SciTech Connect

    Zarkadoula, Evangelia; Devanathan, Ram; Weber, William J; Seaton, M; Todorov, I T; Nordlund, Kai; Dove, Martin T; Trachenko, Kostya

    2014-01-01

    Zirconia is viewed as a material of exceptional resistance to amorphization by radiation damage, and consequently proposed as a candidate to immobilize nuclear waste and serve as an inert nuclear fuel matrix. Here, we perform molecular dynamics simulations of radiation damage in zirconia in the range of 0.1-0.5 MeV energies with account of electronic energy losses. We nd that the lack of amorphizability co-exists with a large number of point defects and their clusters. These, importantly, are largely isolated from each other and therefore represent a dilute damage that does not result in the loss of long-range structural coherence and amorphization. We document the nature of these defects in detail, including their sizes, distribution and morphology, and discuss practical implications of using zirconia in intense radiation environments.

  3. High-energy radiation damage in zirconia: modeling results

    SciTech Connect

    Zarkadoula, Eva; Devanathan, Ram; Weber, William J.; Seaton, Michael; Todorov, Ilian; Nordlund, Kai; Dove, Martin T.; Trachenko, Kostya

    2014-02-28

    Zirconia has been viewed as a material of exceptional resistance to amorphization by radiation damage, and was consequently proposed as a candidate to immobilize nuclear waste and serve as a nuclear fuel matrix. Here, we perform molecular dynamics simulations of radiation damage in zirconia in the range of 0.1-0.5 MeV energies with the account of electronic energy losses. We find that the lack of amorphizability co-exists with a large number of point defects and their clusters. These, importantly, are largely disjoint from each other and therefore represent a dilute damage that does not result in the loss of long-range structural coherence and amorphization. We document the nature of these defects in detail, including their sizes, distribution and morphology, and discuss practical implications of using zirconia in intense radiation environments.

  4. High-energy radiation damage in zirconia: Modeling results

    NASA Astrophysics Data System (ADS)

    Zarkadoula, E.; Devanathan, R.; Weber, W. J.; Seaton, M. A.; Todorov, I. T.; Nordlund, K.; Dove, M. T.; Trachenko, K.

    2014-02-01

    Zirconia is viewed as a material of exceptional resistance to amorphization by radiation damage, and consequently proposed as a candidate to immobilize nuclear waste and serve as an inert nuclear fuel matrix. Here, we perform molecular dynamics simulations of radiation damage in zirconia in the range of 0.1-0.5 MeV energies with account of electronic energy losses. We find that the lack of amorphizability co-exists with a large number of point defects and their clusters. These, importantly, are largely isolated from each other and therefore represent a dilute damage that does not result in the loss of long-range structural coherence and amorphization. We document the nature of these defects in detail, including their sizes, distribution, and morphology, and discuss practical implications of using zirconia in intense radiation environments.

  5. Experimental and theoretical high energy physics research. [UCLA

    SciTech Connect

    Buchanan, Charles D.; Cline, David B.; Byers, N.; Ferrara, S.; Peccei, R.; Hauser, Jay; Muller, Thomas; Atac, Muzaffer; Slater, William; Cousins, Robert; Arisaka, Katsushi

    1992-01-01

    Progress in the various components of the UCLA High-Energy Physics Research program is summarized, including some representative figures and lists of resulting presentations and published papers. Principal efforts were directed at the following: (I) UCLA hadronization model, PEP4/9 e{sup +}e{sup {minus}} analysis, {bar P} decay; (II) ICARUS and astroparticle physics (physics goals, technical progress on electronics, data acquisition, and detector performance, long baseline neutrino beam from CERN to the Gran Sasso and ICARUS, future ICARUS program, and WIMP experiment with xenon), B physics with hadron beams and colliders, high-energy collider physics, and the {phi} factory project; (III) theoretical high-energy physics; (IV) H dibaryon search, search for K{sub L}{sup 0} {yields} {pi}{sup 0}{gamma}{gamma} and {pi}{sup 0}{nu}{bar {nu}}, and detector design and construction for the FNAL-KTeV project; (V) UCLA participation in the experiment CDF at Fermilab; and (VI) VLPC/scintillating fiber R D.

  6. Crystal structure and band gap studies of sodalite: experimental and calculated results

    NASA Astrophysics Data System (ADS)

    Pan, Lijun; Liu, Wanchao; Chen, Weiguang; Yan, Kun; Yang, Huizhi; Yu, Jia

    2016-02-01

    In this paper, we investigated the crystal structural properties of sodalite sample by X-ray diffraction and the band gap studies by means of UV-Vis absorption spectroscopy, and compared with the calculated results using density functional theory. The results of X-ray diffraction suggests that the chemical formula should be Na8(AlSiO6)4(OH)2·2(H2O). The optimized lattice parameter is found to be larger 0.45% than experimental value and the calculations demonstrated the structural details of the hydrogen bond located in sodalite cage. The hydrogen bond formed by water molecule and hydroxyl is implied from charge distribution analysis. As the rotation angle of O-O lines in hydrogen bond is 51.8°, the structure should be of the lowest energy. The optical band gap is measured to be 4.5-4.7 eV experimentally, while, the calculated value is 4.16 eV which is attributed to the localized state below Fermi level formed by the hydrogen bonds. Our results are favorable for the understanding the role of sodalite in silicate mud and contribute to further disposals and treatments.

  7. Experimental High Energy Physics Research: Direct Detection of Dark Matter

    SciTech Connect

    Witherell, Michael S.

    2014-10-02

    The grant supported research on an experimental search for evidence of dark matter interactions with normal matter. The PI carried out the research as a member of the LUX and LZ collaborations. The LUX research team collected a first data set with the LUX experiment, a large liquid xenon detector installed in the Sanford Underground Research Facility (SURF). The first results were published in Physical Review Letters on March 4, 2014. The journal Nature named the LUX result a scientific highlight of the year for 2013. In addition, the LZ collaboration submitted the full proposal for the Lux Zeplin experiment, which has since been approved by DOE-HEP as a second-generation dark matter experiment. Witherell is the Level 2 manager for the Outer Detector System on the LUX-Zeplin experiment.

  8. Experimental and Analytical Evaluation of a Composite Honeycomb Deployable Energy Absorber

    NASA Technical Reports Server (NTRS)

    Jackson, Karen E.; Kellas, Sotiris; Horta, Lucas G.; Annett, Martin S.; Polanco, Michael A.; Littell, Justin D.; Fasanella, Edwin L.

    2011-01-01

    In 2006, the NASA Subsonic Rotary Wing Aeronautics Program sponsored the experimental and analytical evaluation of an externally deployable composite honeycomb structure that is designed to attenuate impact energy during helicopter crashes. The concept, which is designated the Deployable Energy Absorber (DEA), utilizes an expandable Kevlar honeycomb structure to dissipate kinetic energy through crushing. The DEA incorporates a unique flexible hinge design that allows the honeycomb to be packaged and stowed flat until needed for deployment. A variety of deployment options such as linear, radial, and/or hybrid methods can be used. Experimental evaluation of the DEA utilized a building block approach that included material characterization testing of its constituent, Kevlar -129 fabric/epoxy, and flexural testing of single hexagonal cells. In addition, the energy attenuation capabilities of the DEA were demonstrated through multi-cell component dynamic crush tests, and vertical drop tests of a composite fuselage section, retrofitted with DEA blocks, onto concrete, water, and soft soil. During each stage of the DEA evaluation process, finite element models of the test articles were developed and simulations were performed using the explicit, nonlinear transient dynamic finite element code, LS-DYNA. This report documents the results of the experimental evaluation that was conducted to assess the energy absorption capabilities of the DEA.

  9. Deuteron induced reactions on Ho and La: Experimental excitation functions and comparison with code results

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Adam-Rebeles, R.; Tarkanyi, F.; Takacs, S.; Csikai, J.; Takacs, M. P.; Ignatyuk, A.

    2013-09-01

    Activation products of rare earth elements are gaining importance in medical and technical applications. In stacked foil irradiations, followed by high resolution gamma spectroscopy, the cross-sections for production of 161,165Er, 166gHo on 165Ho and 135,137m,137g,139Ce, 140La, 133m,133g,cumBa and 136Cs on natLa targets were measured up to 50 MeV. Reduced uncertainty is obtained by simultaneous remeasurement of the 27Al(d,x)24,22Na monitor reactions over the whole energy range. A comparison with experimental literature values and results from updated theoretical codes (ALICE-D, EMPIRE-D and the TENDL2012 online library) is discussed.

  10. Simulation of diurnal thermal energy storage systems: Preliminary results

    NASA Astrophysics Data System (ADS)

    Katipamula, S.; Somasundaram, S.; Williams, H. R.

    1994-12-01

    This report describes the results of a simulation of thermal energy storage (TES) integrated with a simple-cycle gas turbine cogeneration system. Integrating TES with cogeneration can serve the electrical and thermal loads independently while firing all fuel in the gas turbine. The detailed engineering and economic feasibility of diurnal TES systems integrated with cogeneration systems has been described in two previous PNL reports. The objective of this study was to lay the ground work for optimization of the TES system designs using a simulation tool called TRNSYS (TRaNsient SYstem Simulation). TRNSYS is a transient simulation program with a sequential-modular structure developed at the Solar Energy Laboratory, University of Wisconsin-Madison. The two TES systems selected for the base-case simulations were: (1) a one-tank storage model to represent the oil/rock TES system; and (2) a two-tank storage model to represent the molten nitrate salt TES system. Results of the study clearly indicate that an engineering optimization of the TES system using TRNSYS is possible. The one-tank stratified oil/rock storage model described here is a good starting point for parametric studies of a TES system. Further developments to the TRNSYS library of available models (economizer, evaporator, gas turbine, etc.) are recommended so that the phase-change processes is accurately treated.

  11. Inter-species extrapolation of skin heating resulting from millimeter wave irradiation: modeling and experimental results.

    PubMed

    Nelson, D A; Walters, T J; Ryan, K L; Emerton, K B; Hurt, W D; Ziriax, J M; Johnson, L R; Mason, P A

    2003-05-01

    This study reports measurements of the skin surface temperature elevations during localized irradiation (94 GHz) of three species: rat (irradiated on lower abdomen), rhesus monkey (posterior forelimb), and human (posterior forearm). Two exposure conditions were examined: prolonged, low power density microwaves (LPM) and short-term, high power density microwaves (HPM). Temperature histories were compared with calculations from a bio-heat transfer model. The mean peak surface temperature increase was approximately 7.0 degrees C for the short-term HPM exposures for all three species/locations, and 8.5 degrees C (monkey, human) to 10.5 degrees C (rat) for the longer-duration LPM exposures. The HPM temperature histories are in close agreement with a one-dimensional conduction heat transfer model with negligible blood flow. The LPM temperature histories were compared with calculations from the bio-heat model, evaluated for various (constant) blood flow rates. Results suggest a variable blood flow model, reflecting a dynamic thermoregulatory response, may be more suited to describing skin surface temperature response under long-duration MMW irradiation.

  12. VX hydrolysis by human serum paraoxonase 1: a comparison of experimental and computational results.

    PubMed

    Peterson, Matthew W; Fairchild, Steven Z; Otto, Tamara C; Mohtashemi, Mojdeh; Cerasoli, Douglas M; Chang, Wenling E

    2011-01-01

    Human Serum paraoxonase 1 (HuPON1) is an enzyme that has been shown to hydrolyze a variety of chemicals including the nerve agent VX. While wildtype HuPON1 does not exhibit sufficient activity against VX to be used as an in vivo countermeasure, it has been suggested that increasing HuPON1's organophosphorous hydrolase activity by one or two orders of magnitude would make the enzyme suitable for this purpose. The binding interaction between HuPON1 and VX has recently been modeled, but the mechanism for VX hydrolysis is still unknown. In this study, we created a transition state model for VX hydrolysis (VX(ts)) in water using quantum mechanical/molecular mechanical simulations, and docked the transition state model to 22 experimentally characterized HuPON1 variants using AutoDock Vina. The HuPON1-VX(ts) complexes were grouped by reaction mechanism using a novel clustering procedure. The average Vina interaction energies for different clusters were compared to the experimentally determined activities of HuPON1 variants to determine which computational procedures best predict how well HuPON1 variants will hydrolyze VX. The analysis showed that only conformations which have the attacking hydroxyl group of VX(ts) coordinated by the sidechain oxygen of D269 have a significant correlation with experimental results. The results from this study can be used for further characterization of how HuPON1 hydrolyzes VX and design of HuPON1 variants with increased activity against VX.

  13. Experimental validation of a novel compact focusing scheme for future energy-frontier linear lepton colliders.

    PubMed

    White, G R; Ainsworth, R; Akagi, T; Alabau-Gonzalvo, J; Angal-Kalinin, D; Araki, S; Aryshev, A; Bai, S; Bambade, P; Bett, D R; Blair, G; Blanch, C; Blanco, O; Blaskovic-Kraljevic, N; Bolzon, B; Boogert, S; Burrows, P N; Christian, G; Corner, L; Davis, M R; Faus-Golfe, A; Fukuda, M; Gao, J; García-Morales, H; Geffroy, N; Hayano, H; Heo, A Y; Hildreth, M; Honda, Y; Huang, J Y; Hwang, W H; Iwashita, Y; Jang, S; Jeremie, A; Kamiya, Y; Karataev, P; Kim, E S; Kim, H S; Kim, S H; Kim, Y I; Komamiya, S; Kubo, K; Kume, T; Kuroda, S; Lam, B; Lekomtsev, K; Liu, S; Lyapin, A; Marin, E; Masuzawa, M; McCormick, D; Naito, T; Nelson, J; Nevay, L J; Okugi, T; Omori, T; Oroku, M; Park, H; Park, Y J; Perry, C; Pfingstner, J; Phinney, N; Rawankar, A; Renier, Y; Resta-López, J; Ross, M; Sanuki, T; Schulte, D; Seryi, A; Shevelev, M; Shimizu, H; Snuverink, J; Spencer, C; Suehara, T; Sugahara, R; Takahashi, T; Tanaka, R; Tauchi, T; Terunuma, N; Tomás, R; Urakawa, J; Wang, D; Warden, M; Wendt, M; Wolski, A; Woodley, M; Yamaguchi, Y; Yamanaka, T; Yan, J; Yokoya, K; Zimmermann, F

    2014-01-24

    A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

  14. Experimental demonstration of energy-chirp compensation by a tunable dielectric-based structure.

    PubMed

    Antipov, S; Baturin, S; Jing, C; Fedurin, M; Kanareykin, A; Swinson, C; Schoessow, P; Gai, W; Zholents, A

    2014-03-21

    A tunable energy-chirp compensator was used to remove a correlated energy chirp from the 60-MeV beam at the Brookhaven National Laboratory Accelerator Test Facility. The compensator operates through the interaction of the wakefield of the electron bunch with itself and consists of a planar structure comprised of two alumina bars with copper-plated backs separated by an adjustable beam aperture. By changing the gap size, the correlated energy chirp of the electron bunch was completely removed. Calculations show that this device, properly scaled to account for the electron bunch charge and length, can be used to remove residual correlated energy spread at the end of the linacs used for free-electron lasers. The experimental results are shown to be in good agreement with numerical simulations. Application of this technique can significantly simplify linac design and improve free-electron lasers performance.

  15. Experimental analysis of energy harvesting from self-induced flutter of a composite beam

    SciTech Connect

    Zakaria, Mohamed Y. Al-Haik, Mohammad Y.; Hajj, Muhammad R.

    2015-07-13

    Previous attempts to harvest energy from aeroelastic vibrations have been based on attaching a beam to a moving wing or structure. Here, we exploit self-excited oscillations of a fluttering composite beam to harvest energy using piezoelectric transduction. Details of the beam properties and experimental setup are presented. The effects of preset angle of attack, wind speed, and load resistance on the levels of harvested power are determined. The results point to a complex relation between the aerodynamic loading and its impact on the static deflection and amplitudes of the limit cycle oscillations on one hand and the load resistance and level of power harvested on the other hand.

  16. Experimental verification of an energy consumption signal tool for operational decision support in an office building

    SciTech Connect

    Pavlak, Gregory S.; Henze, Gregor P.; Hirsch, Adam I.; Florita, Anthony R.; Dodier, Robert H.

    2016-12-01

    This paper demonstrates an energy signal tool to assess the system-level and whole-building energy use of an office building in downtown Denver, Colorado. The energy signal tool uses a traffic light visualization to alert a building operator to energy use which is substantially different from expected. The tool selects which light to display for a given energy end-use by comparing measured energy use to expected energy use, accounting for uncertainty. A red light is only displayed when a fault is likely enough, and abnormal operation costly enough, that taking action will yield the lowest cost result. While the theoretical advances and tool development were reported previously, it has only been tested using a basic building model and has not, until now, been experimentally verified. Expected energy use for the field demonstration is provided by a compact reduced-order representation of the Alliance Center, generated from a detailed DOE-2.2 energy model. Actual building energy consumption data is taken from the summer of 2014 for the office building immediately after a significant renovation project. The purpose of this paper is to demonstrate a first look at the building following its major renovation compared to the design intent. The tool indicated strong under-consumption in lighting and plug loads and strong over-consumption in HVAC energy consumption, which prompted several focused actions for follow-up investigation. In addition, this paper illustrates the application of Bayesian inference to the estimation of posterior parameter probability distributions to measured data. Practical discussion of the application is provided, along with additional findings from further investigating the significant difference between expected and actual energy consumption.

  17. Comparison between Theoretical Calculation and Experimental Results of Excitation Functions for Production of Relevant Biomedical Radionuclides

    SciTech Connect

    Menapace, E.; Birattari, C.; Bonardi, M.L.; Groppi, F.; Morzenti, S.; Zona, C.

    2005-05-24

    The radionuclide production for biomedical applications has been brought up in the years, as a special nuclear application, at INFN LASA Laboratory, particularly in co-operation with the JRC-Ispra of EC. Mainly scientific aspects concerning radiation detection and the relevant instruments, the measurements of excitation functions of the involved nuclear reactions, the requested radiochemistry studies and further applications have been investigated. On the side of the nuclear data evaluations, based on nuclear model calculations and critically selected experimental data, the appropriate competence has been developed at ENEA Division for Advanced Physics Technologies. A series of high specific activity accelerator-produced radionuclides in no-carrier-added (NCA) form, for uses in metabolic radiotherapy and for PET radiodiagnostics, are investigated. In this work, last revised measurements and model calculations are reviewed for excitation functions of natZn(d,X)64Cu, 66Ga reactions, referring to irradiation experiments at K=38 variable energy Cyclotron of JRC-Ispra. Concerning the reaction data for producing 186gRe and 211At/211gPo (including significant emission spectra) and 210At, most recent and critically selected experimental results are considered and discussed in comparison with model calculations paying special care to pre-equilibrium effects estimate and to the appropriate overall parameterization. Model calculations are presented for 226Ra(p,2n)225Ac reaction, according to the working program of the ongoing IAEA CRP on the matter.

  18. Very low energy supernovae and their resulting transients

    NASA Astrophysics Data System (ADS)

    Lovegrove, Elizabeth

    Core-collapse supernovae play a key role in many of astrophysical processes, but the details of how these explosive events work remain elusive. Many questions about the CCSN explosion mechanism and progenitor stars could be answered by either detecting very-low-energy supernovae (VLE SNe) or alternately placing a tight upper bound on their fraction of the CCSN population. However, VLE SNe are by definition dim events. Many VLE SNe result from the failure of the standard CCSN explosion mechanism, meaning that any observable signature must be created by secondary processes either before or during the collapse. In this dissertation I examine alternate means of producing transients in otherwise-failed CCSNe and consider the use of shock breakout flashes to both detect VLE SNe and retrieve progenitor star information. I begin by simulating neutrino-mediated mass loss in CCSNe progenitors to show that a dim, unusual, but still observable transient can be produced. I then simulate shock breakout flashes in VLE SNe for both the purposes of detection as well as extracting information about the exploding star. I discuss particular challenges of modeling shock breakout at low energies and behaviors unique to this regime, in particular the behavior of the spectral temperature. All simulations in this dissertation were done with the CASTRO radiation-hydrodynamic code.

  19. Nonlinear numerical modelling and experimental validation of multilayer piezoelectric vibration energy scavengers

    NASA Astrophysics Data System (ADS)

    Blažević, D.; Zelenika, S.

    2015-05-01

    Scavenging of low-level ambient vibrations i.e. the conversion of kinetic into electric energy, is proven as effective means of powering low consumption electronic devices such as wireless sensor nodes. Cantilever based scavengers are characterised by several advantages and thus thoroughly investigated; analytical models based on a distributed parameter approach, Euler-Bernoulli beam theory and eigenvalue analysis have thus been developed and experimentally verified. Finite element models (FEM) have also been proposed employing different modelling approaches and commercial software packages with coupled analysis capabilities. An approach of using a FEM analysis of a piezoelectric cantilever bimorph under harmonic excitation is used in this work. Modal, harmonic and linear and nonlinear transient analyses are performed. Different complex dynamic effects are observed and compared to the results obtained by using a distributed parameter model. The influence of two types of finite elements and three mesh densities is also investigated. A complex bimorph cantilever, based on commercially available Midé Technology® Volture energy scavengers, is then considered. These scavengers are characterised by an intricate multilayer structure not investigated so far in literature. An experimental set-up is developed to evaluate the behaviour of the considered class of devices. The results of the modal and the harmonic FEM analyses of the behaviour of the multilayer scavengers are verified experimentally for three different tip masses and 12 different electrical load values. A satisfying agreement between numerical and experimental results is achieved.

  20. Experimental evaluation of a stationary spherical reflector tracking absorber solar energy collector

    NASA Technical Reports Server (NTRS)

    Steward, W. G.; Kreider, J. F.; Caruso, P. S., Jr.; Kreith, F.

    1976-01-01

    This article presents experimental data for the thermal performance of a stationary, spherical-reflector, tracking-absorber solar energy collector (SRTA). The principle of operation and details of thermal performance of such an SRTA have previously been described. These experimental results were compared with the predictions of a thermal analysis previously published. Experimental results were compared with the prediction of Kreider's computer model. Within the range of the temperature of the experiments, the predicted performance of the unit agreed well with experimental data collected under clear sky conditions. In addition, the extrapolation of the efficiency to higher temperature is shown so that the potential of an SRTA solar collector as a means of providing high temperature steam to operate an electric power facility or for process heat can be evaluated. As a result of the tests conducted by NASA, and an economic analysis not yet publicly available, it appears that the SRTA solar collector concept will be economically viable in competition with any other existing solar system in providing electrical energy.

  1. Research results for the Tornado wind energy system: analysis and conclusions

    SciTech Connect

    Jacobs, E.W.

    1985-02-01

    The Tornado Wind Energy System (TWES) concept utilizes a wind-driven vortex confined by a hollow tower to create a low-pressure core intended to serve as a turbine exhaust reservoir. The turbine inlet flow is provided by a separate ram air supply. Numerous experimental and analytical research efforts have investigated the potential of the TWES as a wind energy conversion system (WECS). The present paper summarizes and analyzes much of the research to date on the TWES. A simplified cost analysis incorporating these research results is also included. Based on these analyses, the TWES does not show any significant promise of improving on either the performance or the cost of energy attainable by conventional WECS. The prospects for achieving either a system power coefficient above 0.20 or a cost of energy less than $0.50/kWh (1979 dollars) appear to be poor.

  2. Research results for the Tornado Wind-Energy system: analysis and conclusions

    SciTech Connect

    Jacobs, E.

    1983-01-01

    The Tornado Wind Energy System (TWES) concept utilizes a wind driven vortex confined by a hollow tower to create a low pressure core intended to serve as a turbine exhaust reservoir. The turbine inlet flow is provided by a separate ram air supply. Numerous experimental and analytical research efforts have investigated the potential of the TWES as a wind energy conversion system (WECS). The present paper summarizes and analyzes much of theresearch to date on the TWES. A simplified cost analysis incorporating these research results is also included. Based on these analyses, the TWES does not show significant promise of improving on either the performance or the cost of energy attainable by conventional WECS. The prospects for achieving either a system power coefficient above 0.20 or a cost of energy less than $0.50/kWh (1979 dollars) appear to be poor.

  3. Thermoregulation in homeotherms: central temperature results from optimization of energy transfers.

    PubMed

    Brocas, J; Fromageot, C

    1996-03-01

    In contrast to the classical homeostatic concept of the constancy of the central temperature, this study proposes an original model of thermoregulation based on the optimization of energy transfers. Exchange of the energy consumed or produced by the cell between the cell and the external medium has an associated energy cost. The different variables of the internal medium-flows, pressures, concentrations and also temperatures, since heat is but a particular form of energy--are continuously set at optimal values such that this cost is always minimal for the prevailing constraints with which the organism is faced. The proposed thermoregulatory model accounts for the physiological spatial and temporal variability of the body's temperatures. The predictive curves suggest a new approach to experimental studies concerned with thermal regulation and throw new light on their results.

  4. Energy spectrum of medium energy gamma-rays from the galactic center region. [experimental design

    NASA Technical Reports Server (NTRS)

    Palmeira, R. A. R.; Ramanujarao, K.; Dutra, S. L. G.; Bertsch, D. L.; Kniffen, D. A.; Morris, D. J.

    1978-01-01

    A balloon-borne magnetic core digitized spark chamber with two assemblies of spark-chambers above and below the scintillation counters was used to measure the medium energy gamma ray flux from the galactic center region. Gamma ray calculations are based on the multiple scattering of the pair electrons in 15 aluminum plates interleaved in the spark chamber modules. Counting rates determined during ascent and at ceiling indicate the presence of diffuse component in this energy range. Preliminary results give an integral flux between 15 and 70 MeV compared to the differential points in other results.

  5. Simple Experimental Verification of the Relation between the Band-Gap Energy and the Energy of Photons Emitted by LEDs

    ERIC Educational Resources Information Center

    Precker, Jurgen W.

    2007-01-01

    The wavelength of the light emitted by a light-emitting diode (LED) is intimately related to the band-gap energy of the semiconductor from which the LED is made. We experimentally estimate the band-gap energies of several types of LEDs, and compare them with the energies of the emitted light, which ranges from infrared to white. In spite of…

  6. Energy requirements in nonobese men and women: results from CALERIE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The energy intake necessary to maintain weight and body composition is called the energy requirement for weight maintenance and can be determined by using the doubly labeled water (DLW) method. The objective was to determine the energy requirements of nonobese men and women in the Comprehensive Asse...

  7. Energy & Man's Environment Impact Study. Summary of Results.

    ERIC Educational Resources Information Center

    Horsfall, J. Stuart

    An evaluation was conducted on the effectiveness of Energy and Man's Environment (EME), a nonprofit energy organization which conducts energy programs in 15 states around the United States. Three research questions were addressed: (1) Who is the consumer of EME workshops and the user of EME materials? (2) How do participants view EME workshops.…

  8. Initial Results From The Chandra High Energy Transmission Grating Spectrometer

    NASA Technical Reports Server (NTRS)

    Canizares, C. R.; Davis, D. S.; Dewey, D.; Flanagan, K. A.; Houck, J.; Huenemoerder, D. P.; Marshall, H. L.; Schattenburg, M. L.; Schulz, N. S.; Wise, M.

    2000-01-01

    The High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-ray Observatory provides spectral resolving powers of 200-1000 over the range 0.4-8.0 keV (1.5-30 A) with effective area of 2-200 square centimeters. Initial observations during the activation and calibration phases of the mission show that the HETGS is performing as predicted prior to Chandra launch. The talk presented very preliminary results that illustrate the power of the HETGS for performing detailed studies of a wide range of celestial sources, including plasma diagnostics. This written version gives a brief summary of that talk with examples of preliminary spectra of Capella, the Crab pulsar, SS433 and the SNR E0102-72.

  9. Measured Zero Net Energy Performance: Results, Lessons, and Surprises

    SciTech Connect

    Brown, Carrie; LaRue, Anna; Pigman, Margaret; Roberts, Jon; Kaneda, David; Connelly, Dylan; Elliott, John; Pless, Shanti; Pande, Abhijeet; Dean, Edward; Anbarlilar, Can

    2016-08-26

    As more and more zero net energy (ZNE) buildings are built and monitored, we can learn from both careful case studies of individual projects as well as a broader perspective of trends over time. In a forum sponsored by Pacific Gas and Electric Company (PG&E), eight expert speakers discussed: results and lessons from monitoring occupied ZNE buildings; best practices for setting performance targets and getting actionable performance information, and; things that have surprised them about monitored ZNE buildings. This paper distills the content of the forum by laying out the most common hurdles that are encountered in setting up monitoring projects, frequent performance issues that the monitoring uncovers, and lessons learned that can be applied to future projects.

  10. Experimental Study of High-Energy Processing of Protoplanetary Materials

    NASA Astrophysics Data System (ADS)

    Petaev, M. I.; Jacobsen, S. B.; Remo, J. L.; Adams, R. G.; Sasselov, D. D.

    2006-12-01

    The metal-silicate fractionation in celestial bodies effectively separates siderophile 182W from lithophile 182Hf into the core and mantle, respectively, making the Hf-W chronometer ideal for dating core-formation in differentiated planetary bodies. It is generally believed that there was equilibration of the Hf-W system during primary metal-silicate fractionation of small, initially chondritic, parent bodies. However, the accretion of larger objects like Moon and terrestrial planets generally involves giant impacts, with both the target and projectile probably being differentiated. Then, use of the Hf-W system assumes metal-silicate re-equilibration at high T and P while metal droplets rain through the magma ocean of a growing planet. Currently no experimental data at such conditions exist. Here we report the first results of experiments aimed at studying partitioning of Fe and Ni (proxy for W) between metal and silicate melt formed at high P and T by laser shocks of powered mixtures of pure Fe metal and Ni-bearing ALM-2 dunite. The initial targets with variable metal/dunite ratios were lightly pressed into 6.3 mm pellets (1-3 mm thick) and subjected to single laser pulses (~120-600 J, ~1 nsec). The details of experiments are described in the accompanying abstract by Remo et al. Some shots produced ~ 1 mm round craters in partially preserved targets which have been studied by optical microscopy, SEM and EPMA. The craters have rather rough surfaces and blackened appearance. The SEM images show thin (1-3 microns) films or pockets (3-8 microns) of silicate melt with or without tiny metal blebs which weld together angular grains of olivine and metal. The olivine contains no Al2O3 and ~0.4 wt% NiO; the metal is pure Fe. The melt, besides being lighter in the BSE images, shows distinct compositional differences (higher Al2O3 and FeO, lower MgO and SiO2) from olivine. The NiO content in metal-free melt films and pockets is similar to that in the host olivine. Metal in

  11. UVA experimental and high energy physics. Final grant report

    SciTech Connect

    Cox, B.

    1999-10-07

    The period 1992--1997 was a mixture of frustrations and of accomplishments for the UVa HEP group. The experimental HEP group began this period with the completion of a truncated run of Experiment E771 at Fermilab in 1992. This experiment was designed to measure the cross section for beauty production in 800 GeV/c pN interactions. It succeeded in this goal as well as in obtaining one of the best limits on FCNC in charm decays by setting an upper limit on D{sup 0} {r_arrow} {mu}{sup +}{mu}{sup {minus}}. In addition, they were able to measure {Psi}, {Psi}, {chi}{sub 1},{chi}{sub 2} and upsilon production. Three UVa PhD theses have resulted from this experiment (as well as 12 other PhD's at other institutions). At the same time, the UVa experimental group was vigorously pursuing the goal of studying CP violation in B production. This took the form of a proposal to the SSC for a super fixed target facility, the SFT, which would focus on studies of B mesons. B. Cox was the spokesman of this experiment that had over thirty institutions. This proposal EOI-14 had a good reception by the SSC PAC. A R and D activity to prove the technique of crystal channeling was undertaken to prove the accelerator aspects of this proposal. This activity, known as E853 or CEX at Fermilab, resulted in proof of the crystal channeling technique as viable for the extraction of 20 TeV beam at the SSC. In addition to this activity, the UVa group investigated many other aspects of B physics at the SSC. They were among the leaders of the 1993 Snowmass meeting on B Physics at Hadronic Accelerators. The UVa HEP group worked vigorously on developing the ideas for B physics at the SSC, as evidenced by the many different studies listed in the publication list given, up to the very day the SSC was terminated by an act of Congress.

  12. Bent crystal analyzer without grooves for inelastic scattering -- first experimental results

    SciTech Connect

    Kushnir, V.I.; Macrander, A.T.

    1996-11-01

    A new design of a bent crystal analyzer for high energy resolution inelastic X-ray scattering has been recently proposed. It has been theoretically predicted that an analyzer with reflecting planes at a certain angle with respect to a crystal surface, bent with two different radii of curvature, will have the same energy resolution as a perfect crystal. The first experimental measurement obtained at the Advanced Photon Source of a bandwidth of such an analyzer is presented. The overall energy resolution of the analyzer and monochromator observed with a narrow beam is equal to 16.4 meV (FWHM) at 13.84 KeV.

  13. ECAS Phase I fuel cell results. [Energy Conservation Alternatives Study

    NASA Technical Reports Server (NTRS)

    Warshay, M.

    1978-01-01

    This paper summarizes and discusses the fuel cell system results of Phase I of the Energy Conversion Alternatives Study (ECAS). Ten advanced electric powerplant systems for central-station baseload generation using coal were studied by NASA in ECAS. Three types of low-temperature fuel cells (solid polymer electrolyte, SPE, aqueous alkaline, and phosphoric acid) and two types of high-temperature fuel cells (molten carbonate, MC, and zirconia solid electrolyte, SE) were studied. The results indicate that (1) overall efficiency increases with fuel cell temperature, and (2) scale-up in powerplant size can produce a significant reduction in cost of electricity (COE) only when it is accompanied by utilization of waste fuel cell heat through a steam bottoming cycle and/or integration with a gasifier. For low-temperature fuel cell systems, the use of hydrogen results in the highest efficiency and lowest COE. In spite of higher efficiencies, because of higher fuel cell replacement costs integrated SE systems have higher projected COEs than do integrated MC systems. Present data indicate that life can be projected to over 30,000 hr for MC fuel cells, but data are not yet sufficient for similarly projecting SE fuel cell life expectancy.

  14. Energy balance model applied to pasture experimental areas in São Paulo State, Brazil

    NASA Astrophysics Data System (ADS)

    Bayma-Silva, Gustavo; de Castro Teixeira, Antonio Heriberto; de Castro Victoria, Daniel; Furlan Nogueira, Sandra; Freitas Leivas, Janice; Coaguila, Daniel N.; Rodrigues Herling, Valdo

    2016-10-01

    The Simple Algorithm for Evapotranspiration Retrieving (SAFER) was used to estimate biophysical parameters and the energy balance components in two different pasture experimental areas, in the São Paulo state, Brazil. The experimental pastures consist in six rotational (RGS) and three continuous grazing systems (CGS) paddocks. Landsat-8 images from 2013 and 2015 dry and rainy seasons were used, as these presented similar hydrological cycle, with 1,600 mm and 1,613 mm of annual precipitation, resulting in 19 cloud-free images. Bands 1 to 7 and thermal bands 10 and 11 were used with weather data from a station located near the experimental area. NDVI, biomass, evapotranspiration and latent heat flux (λE) temporal values statistically differ CGS from RGS areas. Grazing systems influences the energy partition and these results indicate that RGS benefits biomass production, evapotranspiration and the microclimate, due higher LE values. SAFER is a feasible tool to estimate biophysical parameters and energy balance components in pasture and has potential to discriminate continuous and rotation grazing systems in a temporal analysis.

  15. Toward an Experimental Quantum Chemistry: Exploring a New Energy Partitioning.

    PubMed

    Rahm, Martin; Hoffmann, Roald

    2015-08-19

    Following the work of L. C. Allen, this work begins by relating the central chemical concept of electronegativity with the average binding energy of electrons in a system. The average electron binding energy, χ̅, is in principle accessible from experiment, through photoelectron and X-ray spectroscopy. It can also be estimated theoretically. χ̅ has a rigorous and understandable connection to the total energy. That connection defines a new kind of energy decomposition scheme. The changing total energy in a reaction has three primary contributions to it: the average electron binding energy, the nuclear-nuclear repulsion, and multielectron interactions. This partitioning allows one to gain insight into the predominant factors behind a particular energetic preference. We can conclude whether an energy change in a transformation is favored or resisted by collective changes to the binding energy of electrons, the movement of nuclei, or multielectron interactions. For example, in the classical formation of H2 from atoms, orbital interactions dominate nearly canceling nuclear-nuclear repulsion and two-electron interactions. While in electron attachment to an H atom, the multielectron interactions drive the reaction. Looking at the balance of average electron binding energy, multielectron, and nuclear-nuclear contributions one can judge when more traditional electronegativity arguments can be justifiably invoked in the rationalization of a particular chemical event.

  16. Experimental study of energy exchanges between two coupled granular gases

    NASA Astrophysics Data System (ADS)

    Chastaing, J.-Y.; Géminard, J.-C.; Naert, A.

    2016-12-01

    We report on the energy exchanges between two granular gases of different densities coupled electromechanically by immersed blades attached to dc motors. Zeroing the energy flux between the two subsystems, we demonstrate that an immersed blade is a convenient way to assess the properties of the granular gases, provided that the dissipation in the motor is properly taken into account. In addition, when the two gases have different densities, the fluctuations of the energy flux are asymmetric, very intermittent, and with most probable zero flux. We show that, for weak coupling, the main features of the energy exchanges can be explained considering the fluctuations of the two subsystems.

  17. Detailed theoretical and experimental analysis of low-energy electron-N2 scattering

    NASA Astrophysics Data System (ADS)

    Sun, Weiguo; Morrison, Michael A.; Isaacs, William A.; Trail, Wayne K.; Alle, Dean T.; Gulley, R. J.; Brennan, Michael J.; Buckman, Stephen J.

    1995-08-01

    We have carried out a comprehensive theoretical and experimental study of electron scattering from molecular nitrogen at energies below 10.0 eV. In the theoretical component of this project we have generated differential and integral cross sections for elastic scattering and vibrational excitation in converged vibrational close-coupling calculations. In the experiments, we have measured differential cross sections for these processes at scattering angles from 20° to 130° in a crossed-beam experiment at a large number of energies between 0.55 and 10 eV and, in a complementary time-of-flight experiment, total cross sections at energies between 0.08 and 10.0 eV. The measured angular distributions have been extrapolated to 0° and 180° using a procedure based on a nonlinear least-squares fit constrained by known physical properties of the e-N2 scattering matrix; numerical integration of the resulting extrapolated distributions yields integrated cross sections with almost no error beyond that inherent in the measured angular data. We find generally good agreement between the present experimental and theoretical cross section, particularly at energies near the Πg resonance near 2.39 eV. In previous studies of scattering in this region, such comparisons have been made problematical by the difficulty of ascertaining the appropriate theoretical scattering energy. We recommend here a protocol for resolving this problem for both elastic scattering and vibrational excitation.

  18. Experimental and numerical study of cellulose-based electro-active paper energy harvester

    NASA Astrophysics Data System (ADS)

    Abas, Zafar; Kim, Heung Soo; Zhai, Lindong; Kim, Jaehwan

    2014-04-01

    In this present study experimental and finite element analysis of cellulose based electro-active paper energy harvester is presented. Electro-active paper coated with metal electrode is a smart form of cellulose and exhibit piezoelectric effect. Specimens were prepared by depositing electrodes on both sides of the cellulose film. A 50 mm x 50 mm cellulose film coated with aluminum electrodes was bonded on 100 mm x 50 mm x 1 mm aluminum host structure. The voltage output to input acceleration frequency response across a load resistor of 1 MΩ is recorded by conventional energy harvesting experimental setup at the fundamental vibration mode of the EAPap cantilever beam. A coupled piezoelectric-circuit finite element model is developed in which load resistor is directly connected to energy scavenging device. Voltage output FRF is measured for the cases, without proof mass, and by adding a 2 grams proof mass near the tip of the cantilever. The experimental voltage FRF value is 7.6 V/g at 75.1 Hz and is improved to 13.8 V/g at 62.2 Hz when a stainless steel proof mass of 2 grams is added. The presented CPC-FEM model results agree reasonably well with the experimental results. Despite the fact that the electro-mechanical coupling coefficient of electro-active paper is lower than other available piezoelectric materials, it is biocompatible, cheap and naturally occurring polymeric material. It is also very flexible and posses similar piezoelectric characteristics such a PVDF which inspire to use EAPap in energy harvesting applications.

  19. Comparative studies on shielding properties of some steel alloys using Geant4, MCNP, WinXCOM and experimental results

    NASA Astrophysics Data System (ADS)

    Singh, Vishwanath P.; Medhat, M. E.; Shirmardi, S. P.

    2015-01-01

    The mass attenuation coefficients, μ/ρ and effective atomic numbers, Zeff of some carbon steel and stainless steel alloys have been calculated by using Geant4, MCNP simulation codes for different gamma ray energies, 279.1 keV, 661.6 keV, 662 keV, 1115.5 keV, 1173 keV and 1332 keV. The simulation results of Zeff using Geant4 and MCNP codes have been compared with possible available experimental results and theoretical WinXcom, and good agreement has been observed. The simulated μ/ρ and Zeff values using Geant4 and MCNP code signifies that both the simulation process can be followed to determine the gamma ray interaction properties of the alloys for energies wherever analogous experimental results may not be available. This kind of studies can be used for various applications such as for radiation dosimetry, medical and radiation shielding.

  20. Review of lattice results concerning low-energy particle physics

    SciTech Connect

    Aoki, S.; Aoki, Y.; Bernard, C.; Blum, T.; Colangelo, G.; Della Morte, M.; Dürr, S.; El-Khadra, A. X.; Fukaya, H.; Horsley, R.; Jüttner, A.; Kaneko, T.; Laiho, J.; Lellouch, L.; Leutwyler, H.; Lubicz, V.; Lunghi, E.; Necco, S.; Onogi, T.; Pena, C.; Sachrajda, C. T.; Sharpe, S. R.; Simula, S.; Sommer, R.; Van de Water, R. S.; Vladikas, A.; Wenger, U.; Wittig, H.

    2014-09-01

    We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f+(0), arising in semileptonic K -> pi transition at zero momentum transfer, as well as the decay constant ratio fK/fpi of decay constants and its consequences for the CKM matrix elements Vus and Vud. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)LxSU(2)R and SU(3)LxSU(3)R Chiral Perturbation Theory and review the determination of the BK parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, for this review, we focus on D- and B-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant alpha_s.

  1. Review of lattice results concerning low-energy particle physics

    DOE PAGES

    Aoki, S.; Aoki, Y.; Bernard, C.; ...

    2014-09-01

    We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f+(0), arising in semileptonic K -> pi transition at zero momentum transfer, as well as the decay constant ratio fK/fpi of decay constants and its consequences for the CKM matrix elements Vus and Vud. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)LxSU(2)R and SU(3)LxSU(3)R Chiral Perturbation Theory and review the determination ofmore » the BK parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, for this review, we focus on D- and B-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant alpha_s.« less

  2. Review of lattice results concerning low-energy particle physics.

    PubMed

    Aoki, S; Aoki, Y; Bernard, C; Blum, T; Colangelo, G; Della Morte, M; Dürr, S; El-Khadra, A X; Fukaya, H; Horsley, R; Jüttner, A; Kaneko, T; Laiho, J; Lellouch, L; Leutwyler, H; Lubicz, V; Lunghi, E; Necco, S; Onogi, T; Pena, C; Sachrajda, C T; Sharpe, S R; Simula, S; Sommer, R; Van de Water, R S; Vladikas, A; Wenger, U; Wittig, H

    We review lattice results related to pion, kaon, [Formula: see text]- and [Formula: see text]-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor [Formula: see text], arising in semileptonic [Formula: see text] transition at zero momentum transfer, as well as the decay-constant ratio [Formula: see text] of decay constants and its consequences for the CKM matrix elements [Formula: see text] and [Formula: see text]. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of [Formula: see text] and [Formula: see text] Chiral Perturbation Theory and review the determination of the [Formula: see text] parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, we focus here on [Formula: see text]- and [Formula: see text]-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant [Formula: see text].

  3. Analytical characterization and experimental validation of performances of piezoelectric vibration energy scavengers

    NASA Astrophysics Data System (ADS)

    Brusa, E.; Zelenika, S.; Moro, L.; Benasciutti, D.

    2009-05-01

    One of the main requirements in wireless sensor operation is the availability of autonomous power sources sufficiently compact to be embedded in the same housing and, when the application involves living people, wearable. A possible technological solution satisfying these needs is energy harvesting from the environment. Vibration energy scavenging is one of the most studied approaches in this frame. In this work the conversion of kinetic into electric energy via piezoelectric coupling in resonant beams is studied. Various design approaches are analyzed and relevant parameters are identified. Numerical methods are applied to stress and strain analyses as well as to evaluate the voltage and charge generated by electromechanical coupling. The aim of the work is increasing the specific power generated per unit of scavenger volume by optimizing its shape. Besides the conventional rectangular geometry proposed in literature, two trapezoidal shapes, namely the direct and the reversed trapezoidal configuration, are analyzed. They are modeled to predict their dynamic behavior and energy conversion performance. Analytical and FEM models are compared and resulting figures of merit are drawn. Results of a preliminary experimental validation are also given. A systematic validation of characteristic specimens via an experimental campaign is ongoing.

  4. Ejecta from experimental impact craters: Particle size distribution and fragmentation energy

    NASA Astrophysics Data System (ADS)

    Buhl, Elmar; Sommer, Frank; Poelchau, Michael H.; Dresen, Georg; Kenkmann, Thomas

    2014-07-01

    The particle size distribution (PSD) of impact crater ejecta is an important parameter that is useful for understanding the formation of natural craters, the distribution of space debris, the influence of impact events on climate and energy partitioning in impact events. 11 impact experiments into dry and water-saturated sandstone were performed and analyzed. The experiments span a range of impact velocities from 2.5 to 5.3 km s-1 using projectile sizes from 2.5 to 12 mm. Kinetic impact energies between 874 and 80,338 J were achieved. Ejecta of these experiments was collected and the PSD was measured and quantified with power law fits. The resulting power law exponents lie between 2.54 and 2.74. Our results do not show an influence of impact energy or impact velocity on the PSD of impact ejecta. A significant increase in the PSD values was found from dry to water-saturated sandstone targets. We suggest that water saturation of the target has multiple effects on ejecta fragmentation. A comparison of our experimental data with data from the literature shows no correlation between the target material lithology and the ejecta PSD. Interestingly, literature data for disruption experiments revealed a strong influence imparted energy density on the D-values. PSD values were used to calculate the energy spent for target fragmentation and show that the fraction of impact energy used for comminution is in the lower single-digit percentage.

  5. Cotton gin electrical energy use trends and 2009 audit results

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton gin energy costs have risen more than other operating costs. Energy audits were conducted in twenty US cotton gins representing a range of capacities in six states. The average participating saw gin used 39.5 kWh to process a bale. The average roller gin used 62.6 kWh. Gins have become la...

  6. Energy Challenges: Isolating Results Due to Behavior Change

    ERIC Educational Resources Information Center

    Boulton, Kelly; Pallant, Eric; Bradshaw-Wilson, Casey; Choate, Beth; Carbone, Ian

    2017-01-01

    Purpose: Approximately 700 colleges and universities have committed to climate neutrality, which will require significant reductions in energy consumption. This paper aims to explore the effectiveness of an Annual Energy Challenge in curtailing electricity use by changing consumption behaviors at one liberal arts college.…

  7. The first experimental observation of the higher-energy trans conformer of trifluoroacetic acid

    NASA Astrophysics Data System (ADS)

    Apóstolo, R. F. G.; Bazsó, Gábor; Bento, R. R. F.; Tarczay, G.; Fausto, R.

    2016-12-01

    We report here the first experimental observation of the higher-energy conformer of trifluoroacetic acid (trans-TFA). The new conformer was generated by selective narrowband near-infrared vibrational excitation of the lower-energy cis-TFA conformer isolated in cryogenic matrices (Ar, Kr, N2) and shown to spontaneously decay to this latter form in the various matrix media, by tunneling. The decay rates in the different matrices were measured and compared with those of the trans conformers of other carboxylic acids in similar experimental conditions. The experimental studies received support from quantum chemistry calculations undertaken at various levels of approximation, which allowed a detailed characterization of the relevant regions of the potential energy surface of the molecule and the detailed assignment of the infrared spectra of the two conformers in the various matrices. Noteworthly, in contrast to cis-TFA that has its trifluoromethyl group eclipsed with the Cdbnd O bond of the carboxylic moiety, trans-TFA has the trifluoromethyl group eclipsed with the Csbnd O bond. This unusual structure of trans-TFA results from the fact that the relative orientation of the CF3 and COOH groups in this geometry facilitates the establishment of an intramolecular hydrogen-bond-like interaction between the OH group and the closely located in-plane fluorine atom of the CF3 moiety.

  8. Experimental validation of a distributed parameter piezoelectric bimorph cantilever energy harvester

    NASA Astrophysics Data System (ADS)

    Rafique, S.; Bonello, P.

    2010-09-01

    Recent rapid advances in low-power portable electronic applications have motivated researchers and industry to explore schemes to embed an endless power supply mechanism within these systems. These self-charging embedded power supply systems convert ambient energy (vibration, solar, wind, etc) into electrical energy and subsequently provide power to these portable applications. Ambient vibration is one of the most promising sources of energy as it is abundantly present in indoor/outdoor systems. This paper discusses briefly the mathematical model of a bimorph piezoelectric cantilever beam with distributed inertia, and its experimental validation. Research on such a component typically included a tip mass, which reduced the influence of the distributed inertia of the beam and restricted effective operation to low frequencies. The present work excludes the tip mass and only the distributed mass of the harvester is considered. Due to the coupled electromechanical nature of piezoelectric materials, the effects of electrical coupling on the mechanical properties of the harvester are investigated, particularly the dependence of the induced additional stiffness and damping on the electrical load. Both the model and the experimental results show that the resonance frequency and the response amplitude of the harvester exhibit considerable shifts due to the electrical coupling. The experimental work uses both magnitude and Nyquist plots of the electromechanical frequency response functions to thoroughly validate the accuracy and applicability of the distributed parameter model at higher frequencies than previously considered.

  9. Calculation and modeling of the energy released in result of water freezing process (WFP)

    NASA Astrophysics Data System (ADS)

    Ghodsi Hassanabad, M.; Mehrbadi, A. Dehghani

    Process of water freezing in different pressures has been studied with appropriate accuracy and freezing phenomenon has been tested in variety conditions. The effects of pressure on volume change in constant volume and constant pressure have also been reviewed. Calculation of these changes has been done by using the finite difference. Therefore, experimental model has been designed and built to validate these calculations and this experimental model has been studied the power of freezing water during the freezing process in different conditions. Finally, the results were used to design a machine that has an ability to control the power of freezing and turn it into a new clean energy. In this machine, some water is frozen due to temperature difference that is exerting between day and night and energy which is produced by this reaction consumes for creating electrical energy. The amount of extractable power from the temperature difference between day and night were calculated in different temperatures. As an overall result, the most energy extracted from freezing in one cubic meters water with a temperature below -22 °C during the night is 12.8 MJ, the equivalent of using 356 W for 10 h.

  10. University of Virginia experimental and theoretical high energy physics

    SciTech Connect

    Cox, B.

    1991-01-10

    This report discusses research being done in high energy physics at the University of Virginia in the following areas: charmonium; B mesons decay; B physics at the SCC; and symmetry and field theory. (LSP)

  11. Experimental study on the initiation and energy release behavior of polymer bonded explosive materials

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Cai, Xuanming; Ye, Nan; Gao, Yubo

    2017-01-01

    In this paper, an initially sealed vented test chamber and a test projectile with polymer bonded explosive materials were designed to complete the experiments. As the initiation takes place on the interior, great amounts of thermo-chemical energy gases were vented through a hole formed by the penetration process. The gas pressure inside the chamber was used to evaluate the energy release behavior of polymer bonded explosive materials. The experimental results reveal that the impact velocity is significant to the energy release behavior, and in some extent the gas pressure improves with the velocity of the projectile. And the critical initiation velocity and the velocity as the polymer bonded explosive materials reached the maximum reactive efficiency were obtained.

  12. Ripples in the energy of a damped oscillator: The experimental point of view

    NASA Astrophysics Data System (ADS)

    Basano, Lorenzo; Ottonello, Pasquale; Palestini, Valeria

    1996-10-01

    An irreversible transformation of mechanical into thermal energy takes place during the motion of a damped harmonic oscillator, with the result that the level of the total mechanical energy of the system, as a first approximation, decays exponentially with time. A detailed description of this decrease, however, is not usually supplied in textbooks of classical mechanics or general physics. As Karlow has recently pointed out, the negative-exponential decay is modulated by a sequence of energy ripples, owing to the dissipation rate being not constant during the motion. Up to now, the analysis of this behavior has been based only on theoretical considerations; in this work we present the corresponding experimental evidence based on a couple of laboratory demonstrations that use an electrical RLC circuit and a hydrodynamically damped mechanical pendulum.

  13. Recent high energy gamma-ray results from SAS-2

    NASA Technical Reports Server (NTRS)

    Thompson, D. J.; Fichtel, C. E.; Hartman, R. C.; Kniffen, D. A.; Bignami, G. F.; Ogelman, H. B.; Ozel, M. E.; Tumer, T.; Lamb, R. C.

    1977-01-01

    Recent developments in gamma-ray astronomy due to the results from SAS-2 have focused on two areas. First, the emission from the plane of the Galaxy is the dominant feature in the gamma-ray sky. The galactic latitude and longitude distributions are consistent with the concept that the high-energy radiation originates from cosmic rays interacting with interstellar matter, and the measurements support a galactic origin for cosmic rays. Second, searches of the SAS-2 data for emission from localized sources have shown three strong discrete gamma-ray sources: the Crab nebula and PSR 0531 + 21, the Vela supernova remnant and PSR 0833-45, and a source near galactic coordinates 193 deg longitude, +3 deg latitude, which does not appear to be associated with other known celestial objects. Evidence has also been found for pulsed gamma-ray emission from two other radio pulsars, PSR 1818-04 and PSR 1747-46. A localized source near longitudes 76-80 deg may be associated with the X-ray source Cyg X-3.

  14. Gamma Ray Bursts Spectral-Energy correlations: recent results

    NASA Astrophysics Data System (ADS)

    Ghirlanda, Giancarlo

    2011-02-01

    The correlations between the rest frame peak of the νFν spectrum of GRBs (Epeak) and their isotropic energy (Eiso) or luminosity (Liso) could have several implications for the understanding of the GRB prompt emission. These correlations are presently founded on the time-averaged spectral properties of a sample of 95 bursts, with measured redshifts, collected by different instruments in the last 13 years (pre-Fermi). One still open issue is wether these correlations have a physical origin or are due to instrumental selection effects. By studying 10 long and 14 short GRBs detected by Fermi we find that a strong time-resolved correlation between Epeak and the luminosity Liso is present within individual GRBs and that it is consistent with the time-integrated correlation. This result is a direct proof of the existence in both short and long GRBs of a similar physical link between the hardness and the luminosity which is not due to instrumental selection effects. The origin of the Epeak - Liso correlation should be searched in the radiation mechanism of the prompt emission.

  15. Experimental Results for Temporally Overlapping Pulses from Quantel EverGreen 200 Laser

    NASA Technical Reports Server (NTRS)

    Watkins, A. Neal

    2013-01-01

    This report will detail the experimental results and observations obtained while investigating the feasibility of temporally overlapping the two laser pulses from a Quantel EverGreen 200 Laser. This laser was specifically designed for Particle Imaging Velocimetry (PIV) applications and operate by emitting two 532 nm laser pulses that are seperated by an adjustable finite time (typically on the order of ten to hundreds of microseconds). However, the use of this model laser has found recent application for Pressure Sensitive Paint (PSP) testing, especially for rotorcraft research. For this testing, it is desired to only use one laser pulse. While this is easily done by only firing one of the laser heads, more excitation energy could conceivably be had if both laser heads are fired with zero pulse separation. In addition, recently large field-of-view PIV measurements have become possible and need ever increasing laser power to illuminate the larger areas. For this work, two different methods of timing the laser are investigated using both a traditional power meter to monitor laser power as well as a fast photodiode to determine pulse separation. The results are presented here as well as some simple implications for PIV experiments using these methods.

  16. The Development of Experimental Setups And Experimental Studies of The Process of Energy-Technological Processing of Wood

    NASA Astrophysics Data System (ADS)

    Timerbaev, Nail F.; Safin, Rushan G.; Ziatdinova, Dilyara F.; Fomin, Anatoly A.; Mokhovikov, Alexey A.

    2016-08-01

    The paper describes the experimental setups for the study of the various stages of the process of energy-technological processing of wood waste with the production of synthesis gas. The systems for the study of conjugated processes of drying, pyrolysis and gasification, that are an integral part of energy-technological processing of wood wastes were developed. Experimental studies of the processes have identified their basic properties and optimum operating parameters, allowing to obtain a synthesis gas suitable for the chemical synthesis of various olefins.

  17. Newporter Apartments. Deep Energy Retrofit Short Term Results

    SciTech Connect

    Gordon, Andrew; Howard, Luke; Kunkle, Rick; Lubliner, Michael; Auer, Dan; Clegg, Zach

    2012-12-01

    This project demonstrates a path to meet the goal of the Building America program to reduce home energy use by 30% in multi-family buildings. The project demonstrates cost-effective energy savings targets as well as improved comfort and indoor environmental quality (IEQ) associated with deep energy retrofits by a large public housing authority as part of a larger rehabilitation effort. The project focuses on a typical 1960’s vintage low-rise multi-family apartment community (120 units in three buildings).

  18. Newporter Apartments: Deep Energy Retrofit Short-Term Results

    SciTech Connect

    Gordon, A.; Howard, L.; Kunkle, R.; Lubliner, M.; Auer, D.; Clegg, Z.

    2012-12-01

    This project demonstrates a path to meet the goal of the Building America program to reduce home energy use by 30% in multi-family buildings. The project demonstrates cost effective energy savings targets as well as improved comfort and indoor environmental quality (IEQ) associated with deep energy retrofits by a large public housing authority as part of a larger rehabilitation effort. The project focuses on a typical 1960's vintage low-rise multi-family apartment community (120 units in three buildings).

  19. Preliminary results on the conversion of laser energy into electricity

    NASA Technical Reports Server (NTRS)

    Thompson, R. W.; Manista, E. J.; Alger, D. L.

    1978-01-01

    A preliminary experiment was performed to investigate conversion of 10.6 micron laser energy to electrical energy via a laser-sustained argon plasma. Short-circuit currents of 0.7 A were measured between a thoriated-tungsten emitter and collector electrodes immersed in the laser-sustained argon plasma. Open-circuit voltages of about 1.5 V were inferred from the current-voltage load characteristics. The dominant mechanism of laser energy conversion is uncertain at this time. Much higher output powers appear possible.

  20. Numerical and experimental study of a compressive-mode energy harvester under random excitations

    NASA Astrophysics Data System (ADS)

    Li, H. T.; Yang, Z.; Zu, J.; Qin, W. Y.

    2017-03-01

    Piezoelectric energy harvester working in compressive mode has shown outstanding performance under harmonic excitation. However, it is still not clear if the compressive-mode energy harvester can sustain its superiority under random excitations. This paper presents a theoretical and experimental study on a nonlinear compressive-mode piezoelectric energy harvester under random excitations. First, a comprehensive distributed parameter electro-elastic model is developed using the extended Hamilton’s principle and the Euler–Bernoulli beam theory. The embedded force amplification effect of the flexural motion is analytically predicted. Then, the model is numerically solved under random excitations. Strong nonlinear responses was observed in both mechanical and electrical responses. Furthermore, a prototype was fabricated and tested. The experimental data show a good agreement with the model estimations under different level excitations and resistances. The results under random excitation demonstrate that the compressive-mode energy harvester significantly outperforms the state-of-the-art systems in terms of output voltage and normalized power density. If the optimal resistance is chosen in the harvesting circuit, the root mean square power of the prototype will reach three times higher than that of the counterparts.

  1. Experimental valitation of energy harvesting device for civil engineering applications

    NASA Astrophysics Data System (ADS)

    Jung, Hyung-Jo; Kim, In-Ho; Park, Jeongsu

    2012-04-01

    In the field of structural health monitoring using wireless sensors, considerable research attention has been recently given to vibration-based energy harvesting devices for exploring their feasibility as a power source of a wireless sensor node. Most of the previous studies have focused on lab-scale tests for performance validation. For real application, however, field tests on developed energy harvesting devices should be conducted, because their performance may be considerably affected by change in the testing environment. In this study, a new electromagnetic energy harvester is proposed, which is more suitable for civil engineering application, and the preliminary field test on a real cable-stayed bridge are conducted to validate its effectiveness.

  2. Cosmic-Ray Spectrum Approximation Model: Experimental Results and Comparison with Other Models

    NASA Astrophysics Data System (ADS)

    Buchvarova, M.; Draganov, D.

    2013-06-01

    We discuss a model which parameterizes the cosmic-ray (CR) spectrum at different physical conditions, which include the most important effects controlling the CR intensity, like convection-diffusion and energy losses. By a suitable choice of parameters the proposed model results in two approximations: one close to a "force-field" model (describing the energy losses of CRs in the inner heliosphere) and a "convection-diffusion" equation (giving the reduction of CR intensity in the outer heliosphere). The BESS ( Balloon-borne Experiment with Superconducting Spectrometer) experimental spectra of galactic protons and helium nuclei are fitted by the model spectra. The calculation of the unknown parameters is performed using a constrained least squares method as an alternative to the standard chi-square minimization method, because the data contain not only random errors, but also systematic ones. The CR spectrum approximation (CRSA) model is compared to the Moscow State University (MSU) model and the Badhwar and O'Neill (Badhwar and O'Neill, Adv. Space. Res. 14, 749, 1994; Adv. Space Res. 17, 7, 1994) model; we show that depending on the choice of the model parameters it can be examined in the context of one of these two models. We derive a relation between the parameters of the CRSA and MSU models for rigidities above about 10 GV (drift effects are ignored) during periods of low to approximately average levels of solar activity. The drawbacks of the proposed approximation are that: i) the model parameters do not depend on rigidity and ii) the model does not take into account general trends in the variations of the heliospheric magnetic field; thus, the influence of the drift effects on the shape of the spectral curves for different magnetic field polarity swings is ignored.

  3. Numerical and experimental investigation on frosting of energy-recovery ventilator

    NASA Astrophysics Data System (ADS)

    Bilodeau, Stephane; Mercadier, Yves; Brousseau, Patrick

    Frosting of energy-recovery ventilators results in two major problems: increase of pressure losses and reduction of heat transfer rates. Frost formation of heat and mass exchangers used in these ventilation systems is investigated both experimentally and numerically. A numerical model for the prediction of the thermal behavior of the exchanger is presented. The model is validated with experimental data and is then employed to conduct a parametric study. Results indicate that the absolute humidity is the prevailing parameter for characterizing the frosting phenomenon. A frost-mass-fraction chart is established in terms of the absolute humidity of the warm exhaust stream and of the temperature of the cold supply stream. The effect of time and mass flowrate is also evaluated. The transient three-dimensional model shows that the absolute humidity and the temperature of both air flows vary nonlinearly in the frosted zone.

  4. Cold Climate Foundation Retrofit Experimental Hygrothermal Performance. Cloquet Residential Research Facility Laboratory Results

    SciTech Connect

    Goldberg, Louise F.; Harmon, Anna C.

    2015-04-09

    This project was funded jointly by the National Renewable Energy Laboratory (NREL) and Oak Ridge National Laboratory (ORNL). ORNL focused on developing a full basement wall system experimental database to enable others to validate hygrothermal simulation codes. NREL focused on testing the moisture durability of practical basement wall interior insulation retrofit solutions for cold climates. The project has produced a physically credible and reliable long-term hygrothermal performance database for retrofit foundation wall insulation systems in zone 6 and 7 climates that are fully compliant with the performance criteria in the 2009 Minnesota Energy Code. These data currently span the period from November 10, 2012 through May 31, 2014 and are anticipated to be extended through November 2014. The experimental data were configured into a standard format that can be published online and that is compatible with standard commercially available spreadsheet and database software.

  5. Investigations in Experimental and Theoretical High Energy Physics

    SciTech Connect

    Krennrich, Frank

    2013-07-29

    We report on the work done under DOE grant DE-FG02-01ER41155. The experimental tasks have ongoing efforts at CERN (ATLAS), the Whipple observatory (VERITAS) and R&D work on dual readout calorimetry and neutrino-less double beta decay. The theoretical task emphasizes the weak interaction and in particular CP violation and neutrino physics. The detailed descriptions of the final report on each project are given under the appropriate task section of this report.

  6. Experimental Results From Stitched Composite Multi-Bay Fuselage Panels Tested Under Uni-Axial Compression

    NASA Technical Reports Server (NTRS)

    Baker, Donald J.

    2004-01-01

    The experimental results from two stitched VARTM composite panels tested under uni-axial compression loading are presented. The curved panels are divided by frames and stringers into five or six bays with a column of three bays along the compressive loading direction. The frames are supported at the ends to resist out-of-plane translation. Back-to-back strain gages are used to record the strain and displacement transducers were used to record the out-of-plane displacements. In addition a full-field measurement technique that utilizes a camera-based-stero-vision system was used to record displacements. The panels were loaded in increments to determine the first bay to buckle. Loading was discontinued at limit load and the panels were removed from the test machine for impact testing. After impacting at 20 ft-lbs to 25 ft-lbs of energy with a spherical indenter, the panels were loaded in compression until failure. Impact testing reduced the axial stiffness 4 percent and less than 1 percent. Postbuckled axial panel stiffness was 52 percent and 70 percent of the pre-buckled stiffness.

  7. A stereo triangulation system for structural identification: Analytical and experimental results

    NASA Technical Reports Server (NTRS)

    Junkins, J. L.; James, G. H., III; Pollock, T. C.; Rahman, Z. H.

    1988-01-01

    Identification of large space structures' distributed mass, stiffness, and energy dissipation characteristics poses formidable analytical, numerical, and implementation difficulties. Development of reliable on-orbit structural identification methods is important for implementing active vibration suppression concepts which are under widespread study in the large space structures community. Near the heart of the identification problem lies the necessity of making a large number of spatially distributed measurements of the structure's vibratory response and the associated force/moment inputs with sufficient spatial and frequency resolution. In the present paper, we discuss a method whereby tens of active or passive (retro-reflecting) targets on the structure are tracked simultaneously by the focal planes of two or more video cameras mounted on an adjacent platform. Triangulation (optical ray intersection) of the conjugate image centroids yield inertial trajectories of each target on the structure. Given the triangulated motion of the targets, we apply and extend methodology developed by Creamer, Junkins, and Juang to identify the frequencies, mode shapes, and updated estimates for the mass/stiffness/damping parameterization of the structure. The methodology is semi-automated, for example, the post experiment analysis of the video imagery to determine the inertial trajectories of the targets typically requires less than thirty minutes of real time. Using methodology discussed herein, the frequency response of a large number of points on the structure (where reflective targets are mounted) on the structure can be determined from optical measurements alone. For comparison purposes, we also utilize measurements from accelerometers and a calibrated impulse hammer. While our experimental work remains in a research stage of development, we have successfully tracked and stereo triangulated 20 targets (on a vibrating cantilevered grid structure) at a sample frequency of 200 HZ

  8. Experimental Studies of Energy Trends Development of Artificial Ecosystems and Their Links

    NASA Astrophysics Data System (ADS)

    Somova, L. A.; Pechurkin, N. S.; Brilkov, A. V.; Loginov, I. A.; Morozova, E. V.

    Two types of artificial ecosystems with different trophic links have been used for experimental studies of energy trends development and microevolution procecces 1 Microbial populations in artificial ecosystems AES for water purification are the most active transforming organisms and consumers of organic substances of wastes In our experiments we observed different changes in Active Sludge AS structure and populations composition connected with changes in environmental factors and self-development of AS As a result of biological adaptations unutilized substrate concentration decreased in many cases The exact structure of microbial community also changed the biological diversity decreased But in all experiments we observed certain increase of fluxes of energy utilized by the system 2 In experiments with continuous microbial cultures we used Escherichia coli genetically engineered strains They contain in plasmids the cloned genes of marine photobacteria bioluminescence and genes of green fluorescent protein GFP which expression level can be easily changed and controlled We observed kinetic diversity of evolutionary transfers in systems But general mechanisms characterized the increase of used energy flow by bacterial populations under study According to our experimental data at spontaneous development and microevolution processes heat dissipation characterizing the rate of entropy growth increased rather then decreased or maintained steady as G Nikolis and I Prigogin believed The results require further development

  9. Short-Term Test Results. Multifamily Home Energy Efficiency Retrofit

    SciTech Connect

    Lyons, James

    2013-01-01

    Multifamily deep energy retrofits (DERs) represent great potential for energy savings, while also providing valuable insights on research-generated efficiency measures, cost-effectiveness metrics, and risk factor strategies for the multifamily housing industry. This report describes the Bay Ridge project, a base scope retrofit with a goal of achieving 30% savings (relative to pre-retrofit), and a DER scope with a goal of 50% savings (relative to pre-retrofit). Findings from the short-term testing at Bay Ridge include air infiltration reductions of greater than 60% in the DER building; a hybrid heat pump system with a Savings to Investment Ratio (SIR) > 1 (relative to a high efficiency furnace) which also provides the resident with added incentive for energy savings; and duct leakage reductions of > 60% using an aerosolized duct sealing approach.

  10. Simulated and experimental technique optimization of dual-energy radiography: abdominal imaging applications

    NASA Astrophysics Data System (ADS)

    Sabol, John M.; Wheeldon, Samuel J.; Jabri, Kadri N.

    2006-03-01

    With growing clinical acceptance of dual-energy chest radiography, there is increased interest in the application of dual-energy techniques to other clinical areas. This paper describes the creation and experimental validation of a poly-energetic signal-propagation model for technique optimization of new dual-energy clinical applications. The model is verified using phantom experiments simulating typical abdominal radiographic applications such as Intravenous Urography (IVU) and the detection of pelvic and sacral bone lesions or kidney stones in the presence of bowel gas. The model is composed of a spectral signal propagation component and an image-processing component. The spectral propagation component accepts detector specifications, X-ray spectra, phantom and imaging geometry as inputs, and outputs the detected signal and estimated noise. The image-processing module performs dual-energy logarithmic subtraction and returns figures-of-merit such as contrast and contrast-to-noise ratio (CNR), which are evaluated in conjunction with Monte Carlo calculations of dose. Phantoms assembled from acrylic, aluminum, and iodinated contrast-agent filled tubes were imaged using a range of kVp's and dose levels. Simulated and experimental results were compared by dose, clinical suitability, and system limitations in order to yield technique recommendations that optimize one or more figures-of-merit. The model accurately describes phantom images obtained in a low scatter environment. For the visualization of iodinated vessels in the abdomen and the detection of pelvic bone lesions, both simulated and experimental results indicate that dual-energy techniques recommended by the model yield significant improvements in CNR without significant increases in patient dose as compared to conventional techniques. For example the CNR of iodinated vessels can be doubled using two-thirds of the dose of a standard exam. Alternatively, in addition to a standard dose image, the clinician can

  11. Relationship between the surface energy and the histologic results of different titanium surfaces.

    PubMed

    Gehrke, Sergio Alexandre; Zizzari, Vincenzo Luca; Iaculli, Flavia; Mortellaro, Carmen; Tetè, Stefano; Piattelli, Adriano

    2014-05-01

    The aim of this study was to evaluate, through in vitro and in vivo studies, the existence of a relationship between surface energy, for wettability, and the clinical behavior of dental implants with different surfaces, one with a surface treated by sandblasting with titanium oxide microparticles followed by acid-etching treatment (experimental group) and another with a machined surface (control group). For the in vitro tests, a total of 30 titanium disks (15 disks for each group) were evaluated by scanning electron microscopy and dispersive energy spectroscopy and for surface roughness and wettability. For the in vivo tests, a total of 24 implants (12 implants for each group) were inserted in the tibiae of 6 rabbits and were removed after 30 and 60 days for histologic analysis. The results showed that the implants with the experimental surface presented a low wettability, and it also resulted in highly stimulated new bone formation in vivo, when compared with the control group dental implant. As for the bone formation, differences between the different surfaces seemed evident, both in quantity and in quality, as implants from the experimental group showed a higher new bone deposition than that from the control group. Thus, in vitro and in vivo tests demonstrated an excellent biologic response of the surfaces treated by sandblasting with microparticles of titanium oxide followed by acid etching.

  12. Experimental evidence of the decrease of kinetic energy of hadrons in passing through atomic nuclei

    NASA Technical Reports Server (NTRS)

    Strugalski, Z.

    1985-01-01

    Hadrons with kinetic energies higher than the pion production threshold lose their kinetic energies monotonically in traversing atomic nuclei, due to the strong interactions in nuclear matter. This phenomenon is a crude analogy to the energy loss of charged particles in their passage through materials. Experimental evidence is presented.

  13. The calculation of proportional counter energy-deposition spectra from experimental data.

    NASA Technical Reports Server (NTRS)

    Steigerwalt, J. E.; Baily, N. A.

    1973-01-01

    The experimental approach considered requires the measurement of energy-absorption distributions for a set of pathlengths which define a biological volume. A suitable folding procedure is necessary to produce composite energy-absorption distributions. The investigation is concerned with the quality of the prediction of energy-deposition distributions, taking into account distributions measured with a proportional counter.

  14. Planck 2015 results. XIV. Dark energy and modified gravity

    NASA Astrophysics Data System (ADS)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Battaner, E.; Battye, R.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Fergusson, J.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Heavens, A.; Helou, G.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huang, Z.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Lewis, A.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Ma, Y.-Z.; Macías-Pérez, J. F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Marchini, A.; Maris, M.; Martin, P. G.; Martinelli, M.; Martínez-González, E.; Masi, S.; Matarrese, S.; McGehee, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Narimani, A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Pearson, T. J.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Salvatelli, V.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Schaefer, B. M.; Scott, D.; Seiffert, M. D.; Shellard, E. P. S.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Viel, M.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; White, M.; Yvon, D.; Zacchei, A.; Zonca, A.

    2016-09-01

    We study the implications of Planck data for models of dark energy (DE) and modified gravity (MG) beyond the standard cosmological constant scenario. We start with cases where the DE only directly affects the background evolution, considering Taylor expansions of the equation of state w(a), as well as principal component analysis and parameterizations related to the potential of a minimally coupled DE scalar field. When estimating the density of DE at early times, we significantly improve present constraints and find that it has to be below ~2% (at 95% confidence) of the critical density, even when forced to play a role for z < 50 only. We then move to general parameterizations of the DE or MG perturbations that encompass both effective field theories and the phenomenology of gravitational potentials in MG models. Lastly, we test a range of specific models, such as k-essence, f(R) theories, and coupled DE. In addition to the latest Planck data, for our main analyses, we use background constraints from baryonic acoustic oscillations, type-Ia supernovae, and local measurements of the Hubble constant. We further show the impact of measurements of the cosmological perturbations, such as redshift-space distortions and weak gravitational lensing. These additional probes are important tools for testing MG models and for breaking degeneracies that are still present in the combination of Planck and background data sets. All results that include only background parameterizations (expansion of the equation of state, early DE, general potentials in minimally-coupled scalar fields or principal component analysis) are in agreement with ΛCDM. When testing models that also change perturbations (even when the background is fixed to ΛCDM), some tensions appear in a few scenarios: the maximum one found is ~2σ for Planck TT+lowP when parameterizing observables related to the gravitational potentials with a chosen time dependence; the tension increases to, at most, 3σ when external

  15. Short-Term Test Results: Multifamily Home Energy Efficiency Retrofit

    SciTech Connect

    Lyons, J.

    2013-01-01

    Multifamily deep energy retrofits (DERs) represent great potential for energy savings, while also providing valuable insights on research-generated efficiency measures, cost-effectiveness metrics, and risk factor strategies for the multifamily housing industry. The Bay Ridge project is comprised of a base scope retrofit with a goal of achieving 30% savings (relative to pre-retrofit), and a DER scope with a goal of 50% savings (relative to pre-retrofit). The base scope has been applied to the entire complex, except for one 12-unit building which underwent the DER scope. Findings from the implementation, commissioning, and short-term testing at Bay Ridge include air infiltration reductions of greater than 60% in the DER building; a hybrid heat pump system with a Savings to Investment Ratio (SIR) > 1 (relative to a high efficiency furnace) which also provides the resident with added incentive for energy savings; and duct leakage reductions of > 60% using an aerosolized duct sealing approach. Despite being a moderate rehab instead of a gut rehab, the Bay Ridge DER is currently projected to achieve energy savings ≥ 50% compared to pre-retrofit, and the short-term testing supports this estimate.

  16. Influences of Electromagnetic Energy on Bio-Energy Transport through Protein Molecules in Living Systems and Its Experimental Evidence.

    PubMed

    Pang, Xiaofeng; Chen, Shude; Wang, Xianghui; Zhong, Lisheng

    2016-07-25

    The influences of electromagnetic fields (EMFs) on bio-energy transport and its mechanism of changes are investigated through analytic and numerical simulation and experimentation. Bio-energy transport along protein molecules is performed by soliton movement caused by the dipole-dipole electric interactions between neighboring amino acid residues. As such, EMFs can affect the structure of protein molecules and change the properties of the bio-energy transported in living systems. This mechanism of biological effect from EMFs involves the amino acid residues in protein molecules. To study and reveal this mechanism, we simulated numerically the features of the movement of solitons along protein molecules with both a single chain and with three channels by using the Runge-Kutta method and Pang's soliton model under the action of EMFs with the strengths of 25,500, 51,000, 76,500, and 102,000 V/m in the single-chain protein, as well as 17,000, 25,500, and 34,000 V/m in the three-chain protein, respectively. Results indicate that electric fields (EFs) depress the binding energy of the soliton, decrease its amplitude, and change its wave form. Also, the soliton disperses at 102,000 V/m in a single-chain protein and at 25,500 and 34,000 V/m in three-chain proteins. These findings signify that the influence of EMFs on the bio-energy transport cannot be neglected; however, these variations depend on both the strength and the direction of the EF in the EMF. This direction influences the biological effects of EMF, which decrease with increases in the angle between the direction of the EF and that of the dipole moment of amino acid residues; however, randomness at the macroscopic level remains. Lastly, we experimentally confirm the existence of a soliton and the validity of our conclusion by using the infrared spectra of absorption of the collagens, which is activated by another type of EF. Thus, we can affirm that both the described mechanism and the corresponding theory are

  17. Influences of Electromagnetic Energy on Bio-Energy Transport through Protein Molecules in Living Systems and Its Experimental Evidence

    PubMed Central

    Pang, Xiaofeng; Chen, Shude; Wang, Xianghui; Zhong, Lisheng

    2016-01-01

    The influences of electromagnetic fields (EMFs) on bio-energy transport and its mechanism of changes are investigated through analytic and numerical simulation and experimentation. Bio-energy transport along protein molecules is performed by soliton movement caused by the dipole–dipole electric interactions between neighboring amino acid residues. As such, EMFs can affect the structure of protein molecules and change the properties of the bio-energy transported in living systems. This mechanism of biological effect from EMFs involves the amino acid residues in protein molecules. To study and reveal this mechanism, we simulated numerically the features of the movement of solitons along protein molecules with both a single chain and with three channels by using the Runge–Kutta method and Pang’s soliton model under the action of EMFs with the strengths of 25,500, 51,000, 76,500, and 102,000 V/m in the single-chain protein, as well as 17,000, 25,500, and 34,000 V/m in the three-chain protein, respectively. Results indicate that electric fields (EFs) depress the binding energy of the soliton, decrease its amplitude, and change its wave form. Also, the soliton disperses at 102,000 V/m in a single-chain protein and at 25,500 and 34,000 V/m in three-chain proteins. These findings signify that the influence of EMFs on the bio-energy transport cannot be neglected; however, these variations depend on both the strength and the direction of the EF in the EMF. This direction influences the biological effects of EMF, which decrease with increases in the angle between the direction of the EF and that of the dipole moment of amino acid residues; however, randomness at the macroscopic level remains. Lastly, we experimentally confirm the existence of a soliton and the validity of our conclusion by using the infrared spectra of absorption of the collagens, which is activated by another type of EF. Thus, we can affirm that both the described mechanism and the corresponding theory

  18. Bottom-Up Energy Analysis System - Methodology and Results

    SciTech Connect

    McNeil, Michael A.; Letschert, Virginie E.; Stephane, de la Rue du Can; Ke, Jing

    2012-06-15

    The main objective of the development of BUENAS is to provide a global model with sufficient detail and accuracy for technical assessment of policy measures such as energy efficiency standards and labeling (EES&L) programs. In most countries where energy efficiency policies exist, the initial emphasis is on household appliances and lighting. Often, equipment used in commercial buildings, particularly heating, air conditioning and ventilation (HVAC) is also covered by EES&L programs. In the industrial sector, standards and labeling generally covers electric motors and distribution transformers, although a few more types of industrial equipment are covered by some programs, and there is a trend toward including more of them. In order to make a comprehensive estimate of the total potential impacts, development of the model prioritized coverage of as many end uses commonly targeted by EES&L programs as possible, for as many countries as possible.

  19. Experimental ocean acidification alters the allocation of metabolic energy

    PubMed Central

    Pan, T.-C. Francis; Applebaum, Scott L.; Manahan, Donal T.

    2015-01-01

    Energy is required to maintain physiological homeostasis in response to environmental change. Although responses to environmental stressors frequently are assumed to involve high metabolic costs, the biochemical bases of actual energy demands are rarely quantified. We studied the impact of a near-future scenario of ocean acidification [800 µatm partial pressure of CO2 (pCO2)] during the development and growth of an important model organism in developmental and environmental biology, the sea urchin Strongylocentrotus purpuratus. Size, metabolic rate, biochemical content, and gene expression were not different in larvae growing under control and seawater acidification treatments. Measurements limited to those levels of biological analysis did not reveal the biochemical mechanisms of response to ocean acidification that occurred at the cellular level. In vivo rates of protein synthesis and ion transport increased ∼50% under acidification. Importantly, the in vivo physiological increases in ion transport were not predicted from total enzyme activity or gene expression. Under acidification, the increased rates of protein synthesis and ion transport that were sustained in growing larvae collectively accounted for the majority of available ATP (84%). In contrast, embryos and prefeeding and unfed larvae in control treatments allocated on average only 40% of ATP to these same two processes. Understanding the biochemical strategies for accommodating increases in metabolic energy demand and their biological limitations can serve as a quantitative basis for assessing sublethal effects of global change. Variation in the ability to allocate ATP differentially among essential functions may be a key basis of resilience to ocean acidification and other compounding environmental stressors. PMID:25825763

  20. Experimental ocean acidification alters the allocation of metabolic energy.

    PubMed

    Pan, T-C Francis; Applebaum, Scott L; Manahan, Donal T

    2015-04-14

    Energy is required to maintain physiological homeostasis in response to environmental change. Although responses to environmental stressors frequently are assumed to involve high metabolic costs, the biochemical bases of actual energy demands are rarely quantified. We studied the impact of a near-future scenario of ocean acidification [800 µatm partial pressure of CO2 (pCO2)] during the development and growth of an important model organism in developmental and environmental biology, the sea urchin Strongylocentrotus purpuratus. Size, metabolic rate, biochemical content, and gene expression were not different in larvae growing under control and seawater acidification treatments. Measurements limited to those levels of biological analysis did not reveal the biochemical mechanisms of response to ocean acidification that occurred at the cellular level. In vivo rates of protein synthesis and ion transport increased ∼50% under acidification. Importantly, the in vivo physiological increases in ion transport were not predicted from total enzyme activity or gene expression. Under acidification, the increased rates of protein synthesis and ion transport that were sustained in growing larvae collectively accounted for the majority of available ATP (84%). In contrast, embryos and prefeeding and unfed larvae in control treatments allocated on average only 40% of ATP to these same two processes. Understanding the biochemical strategies for accommodating increases in metabolic energy demand and their biological limitations can serve as a quantitative basis for assessing sublethal effects of global change. Variation in the ability to allocate ATP differentially among essential functions may be a key basis of resilience to ocean acidification and other compounding environmental stressors.

  1. Experimental and computational results from a large low-speed centrifugal impeller

    NASA Technical Reports Server (NTRS)

    Hathaway, M. D.; Chriss, R. M.; Wood, J. R.; Strazisar, A. J.

    1993-01-01

    An experimental and computational investigation of the NASA Low-Speed Centrifugal Compressor (LSCC) flow field has been conducted using laser anemometry and Dawes' 3D viscous code. The experimental configuration consists of a backswept impeller followed by a vaneless diffuser. Measurements of the three-dimensional velocity field were acquired at several measurement planes through the compressor. The measurements describe both the throughflow and secondary velocity field along each measurement plane and in several cases provide details of the flow within the blade boundary layers. The experimental and computational results provide a clear understanding of the development of the throughflow momentum wake which is characteristic of centrifugal compressors.

  2. Experimental study of tilting-pad journal bearings - Comparison with theoretical thermoelastohydrodynamic results

    NASA Astrophysics Data System (ADS)

    Fillon, Michel; Bligoud, Jean-Claude; Frene, Jean

    1992-07-01

    Operating characteristics of four-shoe tilting-pad journal bearings of 100 mm diameter and 70 mm length are determined on an experimental device. The load, between pad configuration, varies from 0 to 10,000 N and the rotational speed is up to 4000 rpm. Forty thermocouples are used in order to measure bearing element temperatures (babbitt, shaft, housing and oil baths). The influence of operating conditions and preload ratio on bearing performances are studied. Comparison between theoretical and experimental results is presented. The theoretical model is also performed on a large tilting-pad journal bearing which was investigated experimentally by other authors.

  3. Experimental Analysis of a Piezoelectric Energy Harvesting System for Harmonic, Random, and Sine on Random Vibration

    SciTech Connect

    Cryns, Jackson W.; Hatchell, Brian K.; Santiago-Rojas, Emiliano; Silvers, Kurt L.

    2013-07-01

    Formal journal article Experimental analysis of a piezoelectric energy harvesting system for harmonic, random, and sine on random vibration Abstract: Harvesting power with a piezoelectric vibration powered generator using a full-wave rectifier conditioning circuit is experimentally compared for varying sinusoidal, random and sine on random (SOR) input vibration scenarios. Additionally, the implications of source vibration characteristics on harvester design are discussed. Studies in vibration harvesting have yielded numerous alternatives for harvesting electrical energy from vibrations but piezoceramics arose as the most compact, energy dense means of energy transduction. The rise in popularity of harvesting energy from ambient vibrations has made piezoelectric generators commercially available. Much of the available literature focuses on maximizing harvested power through nonlinear processing circuits that require accurate knowledge of generator internal mechanical and electrical characteristics and idealization of the input vibration source, which cannot be assumed in general application. In this manuscript, variations in source vibration and load resistance are explored for a commercially available piezoelectric generator. We characterize the source vibration by its acceleration response for repeatability and transcription to general application. The results agree with numerical and theoretical predictions for in previous literature that load optimal resistance varies with transducer natural frequency and source type, and the findings demonstrate that significant gains are seen with lower tuned transducer natural frequencies for similar source amplitudes. Going beyond idealized steady state sinusoidal and simplified random vibration input, SOR testing allows for more accurate representation of real world ambient vibration. It is shown that characteristic interactions from more complex vibrational sources significantly alter power generation and power processing

  4. Negative refraction and energy funneling by hyperbolic materials: an experimental demonstration in acoustics.

    PubMed

    García-Chocano, Victor M; Christensen, Johan; Sánchez-Dehesa, José

    2014-04-11

    This Letter reports the design, fabrication, and experimental characterization of hyperbolic materials showing negative refraction and energy funneling of airborne sound. Negative refraction is demonstrated using a stack of five holey Plexiglas plates where their thicknesses, layer separation, hole diameters, and lattice periodicity have been determined to show hyperbolic dispersion around 40 kHz. The resulting hyperbolic material shows a flat band profile in the equifrequency contour allowing the gathering of acoustic energy in a broad range of incident angles and its funneling through the material. Our demonstrations foresee interesting developments based on both phenomena. Acoustic imaging with subwavelength resolution and spot-size converters that harvest and squeeze sound waves irradiating from many directions into a collimated beam are just two possible applications among many.

  5. Experimental investigation of dp → ppn reaction at intermediate energies at Nuclotron

    NASA Astrophysics Data System (ADS)

    Janek, M.; Ladygin, V. P.; Piyadin, S. M.; Gurchin, Yu. V.; Isupov, A. Yu.; Karachuk, J.-T.; Khrenov, A. N.; Kurilkin, A. K.; Kurilkin, P. K.; Livanov, A. N.; Martinska, G.; Reznikov, S. G.; Tarjanyiova, G.; Terekhin, A. A.; Vnukov, I. E.

    2016-11-01

    There are still discrepancies between theory and experimental data in the polarisation observables of dp → ppn reaction in the low and intermediate energies, despite of significant process in the development of theoretical models which include three and more nucleon forces and relativistic effects. The data of dp → ppn reaction have been accumulated at 300, 400 and 500 MeV in the Nuclotron (Dubna, Russia) and partially processed for some kinematic configurations including few in which possible relativistic effects can appear. Kinematic simulation in the framework of ROOT and GEANT4 package have been performed before data processing. Part of the preliminary results are obtained in the form of energy deposit correlations of the two arms working in coincidence and few in the form of kinematic S curve.

  6. Results from Development of Model Specifications for Multifamily Energy Retrofits

    SciTech Connect

    Brozyna, K.

    2012-08-01

    Specifications, modeled after CSI MasterFormat, provide the trade contractors and builders with requirements and recommendations on specific building materials, components and industry practices that comply with the expectations and intent of the requirements within the various funding programs associated with a project. The goal is to create a greater level of consistency in execution of energy efficiency retrofits measures across the multiple regions a developer may work. IBACOS and Mercy Housing developed sample model specifications based on a common building construction type that Mercy Housing encounters.

  7. Results From Development of Model Specifications for Multifamily Energy Retrofits

    SciTech Connect

    Brozyna, Kevin

    2012-08-01

    Specifications, modeled after CSI MasterFormat, provide the trade contractors and builders with requirements and recommendations on specific building materials, components and industry practices that comply with the expectations and intent of the requirements within the various funding programs associated with a project. The goal is to create a greater level of consistency in execution of energy efficiency retrofits measures across the multiple regions a developer may work. IBACOS and Mercy Housing developed sample model specifications based on a common building construction type that Mercy Housing encounters.

  8. Design + energy: results of a national student design competition

    SciTech Connect

    Not Available

    1980-01-01

    A national competition for students in schools of architecture was conducted during the Spring of 1980. The competition was the first of a series of competitions that emphasized the integration of architectural design and energy considerations in medium-scale building projects, and specifically applying passive solar design strategies and the appropriate use of brick masonry materials. Some 300 faculty members and over 2200 students representing 80 of the 92 US architecture schools participated in the program. A summary is presented of the program and the range of submissions grouped by problem types and general climatic region.

  9. Analysis of the energy impacts of the DOE Appropriate Energy Technology Small Grants Program: Method and results

    NASA Astrophysics Data System (ADS)

    Lucarelli, B.; Kessel, J.; Kay, J.; Linse, J.; Tompson, S.; Homer, M.

    1981-08-01

    Methods for assessing the energy savings of projects in the appropriate technology program (AT) and how to apply these methods to obtain estimates of energy impacts was studied. Program energy savings were estimated from project savings by statistical inference. Direct energy savings and methods and results of the economic analysis are discussed. Indirect energy savings and program energy savings and the methods used to obtain them are estimated. Improvement of project selection which increase program energy savings and two approaches for conducting future energy impact studies are presented.

  10. Unfolding linac photon spectra and incident electron energies from experimental transmission data, with direct independent validation

    SciTech Connect

    Ali, E. S. M.; McEwen, M. R.; Rogers, D. W. O.

    2012-11-15

    Purpose: In a recent computational study, an improved physics-based approach was proposed for unfolding linac photon spectra and incident electron energies from transmission data. In this approach, energy differentiation is improved by simultaneously using transmission data for multiple attenuators and detectors, and the unfolding robustness is improved by using a four-parameter functional form to describe the photon spectrum. The purpose of the current study is to validate this approach experimentally, and to demonstrate its application on a typical clinical linac. Methods: The validation makes use of the recent transmission measurements performed on the Vickers research linac of National Research Council Canada. For this linac, the photon spectra were previously measured using a NaI detector, and the incident electron parameters are independently known. The transmission data are for eight beams in the range 10-30 MV using thick Be, Al and Pb bremsstrahlung targets. To demonstrate the approach on a typical clinical linac, new measurements are performed on an Elekta Precise linac for 6, 10 and 25 MV beams. The different experimental setups are modeled using EGSnrc, with the newly added photonuclear attenuation included. Results: For the validation on the research linac, the 95% confidence bounds of the unfolded spectra fall within the noise of the NaI data. The unfolded spectra agree with the EGSnrc spectra (calculated using independently known electron parameters) with RMS energy fluence deviations of 4.5%. The accuracy of unfolding the incident electron energy is shown to be {approx}3%. A transmission cutoff of only 10% is suitable for accurate unfolding, provided that the other components of the proposed approach are implemented. For the demonstration on a clinical linac, the unfolded incident electron energies and their 68% confidence bounds for the 6, 10 and 25 MV beams are 6.1 {+-} 0.1, 9.3 {+-} 0.1, and 19.3 {+-} 0.2 MeV, respectively. The unfolded spectra

  11. Psychoneuroimmunology: an interpretation of experimental and case study evidence towards a paradigm for predictable results.

    PubMed

    Kalt, H W

    2000-07-01

    This paper surveys a number of key experiments and case studies relating to psychoneuroimmunology. It finds that most techniques to influence or even direct the immune system via the mind fall into a series of theoretical categories called passive, active and targeted effects. By examining the results of experiments and studies in the light of these categories a number of important conclusions are drawn. These conclusions explain differences in experimental results, describe those variables that appear to be central to obtaining results, and describe in detail where experimentation should be concentrated to further knowledge of psychoneuroimmunology.

  12. DoSSiER: Database of scientific simulation and experimental results

    SciTech Connect

    Wenzel, Hans; Yarba, Julia; Genser, Krzystof; Elvira, Daniel; Pokorski, Witold; Carminati, Federico; Konstantinov, Dmitri; Ribon, Alberto; Folger, Gunter; Dotti, Andrea

    2016-08-01

    The Geant4, GeantV and GENIE collaborations regularly perform validation and regression tests for simulation results. DoSSiER (Database of Scientific Simulation and Experimental Results) is being developed as a central repository to store the simulation results as well as the experimental data used for validation. DoSSiER can be easily accessed via a web application. In addition, a web service allows for programmatic access to the repository to extract records in json or xml exchange formats. In this paper, we describe the functionality and the current status of various components of DoSSiER as well as the technology choices we made.

  13. Experimental study on the fabrication of advanced materials for energy applications using high energy mechanical milling

    NASA Astrophysics Data System (ADS)

    Narayana Swamy, Ashvin Kumar

    The reaction of aluminum (Al) powder with water has the potential for on demand hydrogen generation. Conventional Al powders, however, react with water slowly due to a highly protective oxide layer on the particle surface. Current methods for Al activation involve harmful and expensive materials. The nano-scale Al powders also remain very expensive and have problems such as a large amount of oxide on the surface. The use of aluminum in an energy generation cycle is also hindered by the fact that, although Al is the most abundant metal in the Earth's crust, its recovery from ore consumes a lot of energy. Recycling aluminum hydroxide, formed as a result of Al reaction with water, would also require large amounts of energy. The energy consumption for production of Al powder and hence its cost could be significantly reduced by using recycled aluminum scrap and waste where aluminum is contained in metallic, non-oxidized form. The research work presented here investigates the preparation of an activated aluminum powder from aluminum foil that is widely available as scrap and waste. The obtained results demonstrate that a highly reactive, fine powder can be obtained from Al foil by high-energy ball milling with sodium chloride (NaCl). The obtained powder readily reacts with hot water, releasing hydrogen. Note that NaCl is an environment-friendly additive that can easily be removed after milling and recycled. After washing NaCl out, the powders retain a high reactivity with respect to hot water. As compared to previously studied activation of commercial Al powders, a major advantage of the investigated process is the feasibility of using secondary aluminum. Another area of research presented here is the synthesis of gallium oxide (Ga2O3) nanostructures for their use as high-temperature sensors. Quasi one-dimensional nanomaterials are of great interest due to increased focus on their importance in physics research and also their applications in the nanodevices industry

  14. Experimental Results with Airfoils Tested in the High-speed Tunnel at Guidonia

    NASA Technical Reports Server (NTRS)

    Ferri, Antonio

    1940-01-01

    The results are presented of a triple series of tests using force measurements, pressure-distribution measurements, and air flow photographs on airfoil sections suitably selected so that comparison could be made between the experimental and theoretical results. The comparison with existing theory is followed by a discussion of the divergences found, and an attempt is made to find their explanation.

  15. OVERVIEW OF RECENT EXPERIMENTAL RESULTS FROM THE DIII-D ADVANCED TOKAMAK PROGRAM

    SciTech Connect

    BURRELL,KH

    2002-11-01

    OAK A271 OVERVIEW OF RECENT EXPERIMENTAL RESULTS FROM THE DIII-D ADVANCED TOKAMAK PROGRAM. The DIII-D research program is developing the scientific basis for advanced tokamak (AT) modes of operation in order to enhance the attractiveness of the tokamak as an energy producing system. Since the last International Atomic Energy Agency (IAEA) meeting, the authors have made significant progress in developing the building blocks needed for AT operation: (1) the authors have doubled the magnetohydrodynamic (MHD) stable tokamak operating space through rotational stabilization of the resistive wall mode; (2) using this rotational stabilization, they have achieved {beta}{sub N}H{sub 89} {le} 10 for 4 {tau}{sub E} limited by the neoclassical tearing mode; (3) using real-time feedback of the electron cyclotron current drive (ECCD) location, they have stabilized the (m,n) = (3,2) neoclassical tearing mode and then increased {beta}{sub T} by 60%; (4) they have produced ECCD stabilization of the (2,1) neoclassical tearing mode in initial experiments; (5) they have made the first integrated AT demonstration discharges with current profile control using ECCD; (6) ECCD and electron cyclotron heating (ECH) have been used to control the pressure profile in high performance plasmas; and (7) they have demonstrated stationary tokamak operation for 6.5 s (36 {tau}{sub E}) at the same fusion gain parameter of {beta}{sub N}H{sub 89}/q{sub 95}{sup 2} {approx} 0.4 as ITER but at much higher q{sub 95} = 4.2. They have developed general improvements applicable to conventional and advanced tokamak operating modes: (1) they have an existence proof of a mode of tokamak operation, quiescent H-mode, which has no pulsed, ELM heat load to the divertor and which can run for long periods of time (3.8 s or 25 {tau}{sub E}) with constant density and constant radiation power; (2) they have demonstrated real-time disruption detection and mitigation for vertical disruption events using high pressure gas jet

  16. Enterotomy fusion with laser energy: preliminary results in rabbit ileum.

    PubMed

    Vlasak, J; Kopchok, G; Dayhovsky, L; Grundfest, W; White, R A

    1989-01-01

    The utility of enterotomy closure with the argon and CO2 lasers was examined in New Zealand white rabbit ileum. Thermal properties of 10 argon (0.5 W power for 30 s, energy fluence 230 J/cm2) and 10 CO2 (1.0 W power for 30 s, energy fluence 2700 J/cm2) laser-fused enterotomies were determined during acute fusion experiments using an AGA 782 digital thermographic camera. Healing of the fusions created by the two lasers was subsequently assessed in an additional group of 28 rabbits by comparing three 1.0-cm longitudinal ileal enterotomies, with each rabbit having both types of laser-welded closures and a sutured control. Thermal measurements made from the 10 closures with each laser revealed that the CO2 fusions generated significantly higher temperatures (max. 198 degrees C, mean 106 +/- 37 degrees C, n = 100) than argon (max. 85.2 degrees C, mean 60.5 + 8.1 degrees C, n = 100) p less than 0.001. In the healing studies, four rabbits died from weld failures (one argon and one CO2 disruption, two rabbits with both welds disrupted). Two additional rabbits died at 1 day and one at 10 days for undetermined reasons. The remainder of the animals were sacrificed at 1 (n = 11), 2 (n = 2) and 4 (n = 9) weeks postoperatively. Sutured closures exhibited more granulation tissue and adhesions surrounding the wounds than did welded closures and seven microabscesses were noted adjacent to sutured repairs. One of the CO2 repairs had an abscess at 4 weeks and none of the argon laser fusions had evidence of disruption or abscess.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Very low-energy nucleon-16O coupled-channel scattering: Results with a phenomenological vibrational model

    NASA Astrophysics Data System (ADS)

    Svenne, J. P.; Canton, L.; Amos, K.; Fraser, P. R.; Karataglidis, S.; Pisent, G.; van der Knijff, D.

    2017-03-01

    We employ a collective vibration coupled-channel model to describe the nucleon-16O cluster systems, obtaining low-excitation spectra for 17O and 17F. Bound and resonance states of the compound systems have been deduced, showing good agreement with experimental spectra. Low-energy scattering cross sections of neutrons and protons from 16O also have been calculated and the results compare well with available experimental data.

  18. Parametric Evaluation of Absorption Losses and Comparison of Numerical Results to Boeing 707 Aircraft Experimental HIRF Results

    NASA Astrophysics Data System (ADS)

    Kitaygorsky, J.; Amburgey, C.; Elliott, J. R.; Fisher, R.; Perala, R. A.

    A broadband (100 MHz-1.2 GHz) plane wave electric field source was used to evaluate electric field penetration inside a simplified Boeing 707 aircraft model with a finite-difference time-domain (FDTD) method using EMA3D. The role of absorption losses inside the simplified aircraft was investigated. It was found that, in this frequency range, none of the cavities inside the Boeing 707 model are truly reverberant when frequency stirring is applied, and a purely statistical electromagnetics approach cannot be used to predict or analyze the field penetration or shielding effectiveness (SE). Thus it was our goal to attempt to understand the nature of losses in such a quasi-statistical environment by adding various numbers of absorbing objects inside the simplified aircraft and evaluating the SE, decay-time constant τ, and quality factor Q. We then compare our numerical results with experimental results obtained by D. Mark Johnson et al. on a decommissioned Boeing 707 aircraft.

  19. Preliminary Experimental Results on Controlled Cardiac Computed Tomography: A Phantom Study

    PubMed Central

    Lu, Yang; Cai, Zhijun; Wang, Ge; Zhao, Jun; Bai, Er-Wei

    2010-01-01

    In this paper, we present the preliminary experimental results on controlled cardiac computed tomography (CT), which aims to reduce the motion artifacts by means of controlling the x-ray source rotation speed. An innovative cardiac phantom enables us to perform this experiment without modifying the scanner. It is the first experiment on the cardiac CT with speed controlled x-ray source. Experimental results demonstrate that the proposed method successfully separates the phantom images at different phases (improve the temporal resolution) though controlling the x-ray speed. PMID:19696470

  20. Negative refraction and lensing at visible wavelength: experimental results using a waveguide array.

    PubMed

    Ferrari, José A; Frins, Erna

    2011-07-04

    Experimental results showing "negative refraction" and some kind of "lensing" -in the microwave-infrared range- are often presented in the literature as undisputable evidence of the existence of composite left-handed materials. The purpose of this paper is to present experimental results on "negative refraction" and "lensing" at visible wavelengths involving a waveguide array formed by a tight-packed bundle of glass fibers. We will demonstrate that the observed phenomena are not necessarily evidence of the existence of left-handed materials and that they can be fully explained by classical optic concepts, e.g. light propagation in waveguides.

  1. Laser induced deflection technique for absolute thin film absorption measurement: optimized concepts and experimental results

    SciTech Connect

    Muehlig, Christian; Kufert, Siegfried; Bublitz, Simon; Speck, Uwe

    2011-03-20

    Using experimental results and numerical simulations, two measuring concepts of the laser induced deflection (LID) technique are introduced and optimized for absolute thin film absorption measurements from deep ultraviolet to IR wavelengths. For transparent optical coatings, a particular probe beam deflection direction allows the absorption measurement with virtually no influence of the substrate absorption, yielding improved accuracy compared to the common techniques of separating bulk and coating absorption. For high-reflection coatings, where substrate absorption contributions are negligible, a different probe beam deflection is chosen to achieve a better signal-to-noise ratio. Various experimental results for the two different measurement concepts are presented.

  2. Multi-Level Experimental and Analytical Evaluation of Two Composite Energy Absorbers

    NASA Technical Reports Server (NTRS)

    Jackson, Karen E.; Littell, Justin D.; Fasanella, Edwin L.; Annett, Martin S.; Seal, Michael D., II

    2015-01-01

    Two composite energy absorbers were developed and evaluated at NASA Langley Research Center through multi-level testing and simulation performed under the Transport Rotorcraft Airframe Crash Testbed (TRACT) research program. A conical-shaped energy absorber, designated the conusoid, was evaluated that consisted of four layers of hybrid carbon-Kevlar plain weave fabric oriented at [+45 deg/-45 deg/-45 deg/+45 deg] with respect to the vertical, or crush, direction. A sinusoidal-shaped energy absorber, designated the sinusoid, was developed that consisted of hybrid carbon-Kevlar plain weave fabric face sheets, two layers for each face sheet oriented at +/-45deg with respect to the vertical direction and a closed-cell ELFOAM P200 polyisocyanurate (2.0-lb/cu ft) foam core. The design goal for the energy absorbers was to achieve average floor-level accelerations of between 25- and 40-g during the full-scale crash test of a retrofitted CH-46E helicopter airframe, designated TRACT 2. Variations in both designs were assessed through dynamic crush testing of component specimens. Once the designs were finalized, subfloor beams of each configuration were fabricated and retrofitted into a barrel section of a CH-46E helicopter. A vertical drop test of the barrel section was conducted onto concrete to evaluate the performance of the energy absorbers prior to retrofit into TRACT 2. The retrofitted airframe was crash tested under combined forward and vertical velocity conditions onto soil, which is characterized as a sand/clay mixture. Finite element models were developed of all test articles and simulations were performed using LS-DYNA, a commercial nonlinear explicit transient dynamic finite element code. Test-analysis results are presented for each energy absorber as comparisons of time-history responses, as well as predicted and experimental structural deformations and progressive damage under impact loading for each evaluation level.

  3. Application of an Unstructured Grid Navier-Stokes Solver to a Generic Helicopter Boby: Comparison of Unstructured Grid Results with Structured Grid Results and Experimental Results

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.

    1999-01-01

    An unstructured-grid Navier-Stokes solver was used to predict the surface pressure distribution, the off-body flow field, the surface flow pattern, and integrated lift and drag coefficients on the ROBIN configuration (a generic helicopter) without a rotor at four angles of attack. The results are compared to those predicted by two structured- grid Navier-Stokes solvers and to experimental surface pressure distributions. The surface pressure distributions from the unstructured-grid Navier-Stokes solver are in good agreement with the results from the structured-grid Navier-Stokes solvers. Agreement with the experimental pressure coefficients is good over the forward portion of the body. However, agreement is poor on the lower portion of the mid-section of the body. Comparison of the predicted surface flow patterns showed similar regions of separated flow. Predicted lift and drag coefficients were in fair agreement with each other.

  4. Evaluating Impacts of CO2 Gas Intrusion Into a Confined Sandstone aquifer: Experimental Results

    DOE PAGES

    Qafoku, Nikolla; Lawter, Amanda R.; Shao, Hongbo; ...

    2014-12-31

    Deep subsurface storage and sequestration of CO2 has been identified as a potential mitigation technique for rising atmospheric CO2 concentrations. Sequestered CO2 represents a potential risk to overlying aquifers if the CO2 leaks from the deep storage reservoir. Experimental and modeling work is required to evaluate potential risks to groundwater quality and develop a systematic understanding of how CO2 leakage may cause important changes in aquifer chemistry and mineralogy by promoting dissolution/precipitation, adsorption/desorption, and redox reactions. Sediments from the High Plains aquifer in Kansas, United States, were used in this investigation, which is part of the National Risk Assessment Partnershipmore » Program sponsored by the US Department of Energy. This aquifer was selected to be representative of consolidated sand and gravel/sandstone aquifers overlying potential CO2 sequestration repositories within the continental US. In this paper, we present results from batch experiments conducted at room temperature and atmospheric pressure with four High Plains aquifer sediments. Batch experiments simulate sudden, fast, and short-lived releases of the CO2 gas as would occur in the case of well failure during injection. Time-dependent release of major, minor, and trace elements were determined by analyzing the contacting solutions. Characterization studies demonstrated that the High Plains aquifer sediments were abundant in quartz and feldspars, and contained about 15 to 20 wt% montmorillonite and up to 5 wt% micas. Some of the High Plains aquifer sediments contained no calcite, while others had up to about 7 wt% calcite. The strong acid extraction tests confirmed that in addition to the usual elements present in most soils, rocks, and sediments, the High Plains aquifer sediments had appreciable amounts of As, Cd, Pb, Cu, and occasionally Zn, which potentially may be mobilized from the solid to the aqueous phase during or after exposure to CO2. However

  5. Evaluating Impacts of CO2 Gas Intrusion Into a Confined Sandstone aquifer: Experimental Results

    SciTech Connect

    Qafoku, Nikolla; Lawter, Amanda R.; Shao, Hongbo; Wang, Guohui; Brown, Christopher F.

    2014-12-31

    Deep subsurface storage and sequestration of CO2 has been identified as a potential mitigation technique for rising atmospheric CO2 concentrations. Sequestered CO2 represents a potential risk to overlying aquifers if the CO2 leaks from the deep storage reservoir. Experimental and modeling work is required to evaluate potential risks to groundwater quality and develop a systematic understanding of how CO2 leakage may cause important changes in aquifer chemistry and mineralogy by promoting dissolution/precipitation, adsorption/desorption, and redox reactions. Sediments from the High Plains aquifer in Kansas, United States, were used in this investigation, which is part of the National Risk Assessment Partnership Program sponsored by the US Department of Energy. This aquifer was selected to be representative of consolidated sand and gravel/sandstone aquifers overlying potential CO2 sequestration repositories within the continental US. In this paper, we present results from batch experiments conducted at room temperature and atmospheric pressure with four High Plains aquifer sediments. Batch experiments simulate sudden, fast, and short-lived releases of the CO2 gas as would occur in the case of well failure during injection. Time-dependent release of major, minor, and trace elements were determined by analyzing the contacting solutions. Characterization studies demonstrated that the High Plains aquifer sediments were abundant in quartz and feldspars, and contained about 15 to 20 wt% montmorillonite and up to 5 wt% micas. Some of the High Plains aquifer sediments contained no calcite, while others had up to about 7 wt% calcite. The strong acid extraction tests confirmed that in addition to the usual elements present in most soils, rocks, and sediments, the High Plains aquifer sediments had appreciable amounts of As, Cd, Pb, Cu, and occasionally Zn, which potentially may be mobilized from the solid to the aqueous phase during or after exposure to CO2. However, the

  6. Electromagnetic Vortex-Based Radar Imaging Using a Single Receiving Antenna: Theory and Experimental Results.

    PubMed

    Yuan, Tiezhu; Wang, Hongqiang; Cheng, Yongqiang; Qin, Yuliang

    2017-03-19

    Radar imaging based on electromagnetic vortex can achieve azimuth resolution without relative motion. The present paper investigates this imaging technique with the use of a single receiving antenna through theoretical analysis and experimental results. Compared with the use of multiple receiving antennas, the echoes from a single receiver cannot be used directly for image reconstruction using Fourier method. The reason is revealed by using the point spread function. An additional phase is compensated for each mode before imaging process based on the array parameters and the elevation of the targets. A proof-of-concept imaging system based on a circular phased array is created, and imaging experiments of corner-reflector targets are performed in an anechoic chamber. The azimuthal image is reconstructed by the use of Fourier transform and spectral estimation methods. The azimuth resolution of the two methods is analyzed and compared through experimental data. The experimental results verify the principle of azimuth resolution and the proposed phase compensation method.

  7. (Experimental studies of elementary particle interactions at high energies)

    SciTech Connect

    Khuri, N.N.

    1990-01-01

    This report includes descriptions of the combined work of both Tasks B and B{sub 1} at Rockefeller University. Some highlights are worth stressing in this brief introduction. First, one should note the active involvement of two members of our group, Ren and Callaway, in understanding the problem of superconductivity, both high and low {Tc}. This reflects the broad reach of many, but perhaps not all, particle physicists. Second, spurred by the Rockefeller environment, some in our group are also looking at problems in biology. As for our main purpose, I would like to single out the results of Sanda and Morozumi on the {Delta}I = {1/2} rule, the work of Bitar, Ren and myself on a new approach to the path integral, S.Y. Pi's results on Chern-Simons non-relativistic quantum mechanics, and finally the work by Lee and collaborators on the origin of Fermion masses and mixing.

  8. Extraction of potential energy in charge asymmetry coordinate from experimental fission data

    NASA Astrophysics Data System (ADS)

    Paşca, H.; Andreev, A. V.; Adamian, G. G.; Antonenko, N. V.

    2016-12-01

    For fissioning isotopes of Ra, Ac, Th, Pa, and U, the potential energies as a function of the charge asymmetry coordinate are extracted from the experimental charge distributions of the fission fragment and compared with the calculated scission-point driving potentials. The role of the potential energy surfaces in the description of the fission charge distribution is discussed.

  9. Review on optical constants of Titan aerosols: Experimental results and modeling/observational data

    NASA Astrophysics Data System (ADS)

    Brassé, Coralie; Muñoz, Olga; Coll, Patrice; Raulin, François

    2014-05-01

    During the last years many studies have been performed to improve the experimental database of optical constants of Titan aerosols. Indeed, the determination of the optical constants of these particles is essential to quantify their capacity to absorb and to scatter solar radiation, and thus to evaluate their role on Titan's radiative balance and climate. The study of optical properties is also crucial to analyze and to better interpret many of Titan's observational data, in particular those acquired during the Cassini-Huygens mission. One way to determine Titan aerosols optical constant is to measure the optical constants of analogues of Titan complex organic material synthesized in the laboratory, usually named Titan's tholins (Sagan and Khare, 1979). But the optical constants depend on the chemical composition, the size and the shape of particles (Raulin et al., 2012). Those three parameters result from the experimental conditions such as energy source, gas mixing ratio, gas pressure, flow rate and irradiation time (Cable et al., 2012). Besides the determination of the refractive index in the laboratory, there are others methods using theoretical models or observational data. Nevertheless, theoretical models are based on laboratory data or/and observational data. The visible - near infrared spectral region of optical constants has been widely studied with laboratory analogues. Comparison of the obtained results suggest that tholins synthesized by Tran et al. (2003) and Majhoub et al. (2012) are the best representative of Titan aerosols with regards to their refractive indexes in this spectral region. The mid-infrared spectral range has been studied only by Imanaka et al. (2012) and slightly by Tran et al. (2003). In that spectral range, Titan tholins do not exhibit the features displayed by Kim and Courtin (2013) from Titan's observations. For spectral region of wavelengths smaller than 0.20µm or higher than 25µm, only the data from Khare et al. (1984) are

  10. Ionization energies of argon clusters: A combined experimental and theoretical study

    NASA Astrophysics Data System (ADS)

    Echt, O.; Fiegele, T.; Rümmele, M.; Probst, M.; Matt-Leubner, S.; Urban, J.; Mach, P.; Leszczynski, J.; Scheier, P.; Märk, T. D.

    2005-08-01

    We have measured appearance energies of Arn+,n⩽30, by electron impact of gas phase clusters. Quantum-chemical calculations have been performed to determine the adiabatic and vertical ionization energies of argon clusters up to n =4 and 6, respectively. The experimental appearance energy of the dimer ion approaches, under suitable cluster source conditions, the adiabatic ionization energy. The agreement with values obtained by photoionization and threshold photoelectron-photoion coincidence (TPEPICO) spectra demonstrates that autoionizing Rydberg states are accessible by electron impact. Appearance energies of larger clusters, though, exceed the TPEPICO values by about 0.5 eV.

  11. Cold Climate Foundation Retrofit Experimental Hygrothermal Performance: Cloquet Residential Research Facility Laboratory Results

    SciTech Connect

    Goldberg, Louise F.; Harmon, Anna C.

    2015-04-01

    Thermal and moisture problems in existing basements create a unique challenge because the exterior face of the wall is not easily or inexpensively accessible. This approach addresses thermal and moisture management from the interior face of the wall without disturbing the exterior soil and landscaping. the interior and exterior environments. This approach has the potential for improving durability, comfort, and indoor air quality. This project was funded jointly by the National Renewable Energy Laboratory (NREL) and Oak Ridge National Laboratory (ORNL). ORNL focused on developing a full basement wall system experimental database to enable others to validate hygrothermal simulation codes. NREL focused on testing the moisture durability of practical basement wall interior insulation retrofit solutions for cold climates. The project has produced a physically credible and reliable long-term hygrothermal performance database for retrofit foundation wall insulation systems in zone 6 and 7 climates that are fully compliant with the performance criteria in the 2009 Minnesota Energy Code. The experimental data were configured into a standard format that can be published online and that is compatible with standard commercially available spreadsheet and database software.

  12. Experimental investigation on the energy deposition and expansion rate under the electrical explosion of aluminum wire in vacuum

    SciTech Connect

    Shi, Zongqian; Wang, Kun; Shi, Yuanjie; Wu, Jian; Han, Ruoyu

    2015-12-28

    Experimental investigations on the electrical explosion of aluminum wire using negative polarity current in vacuum are presented. Current pulses with rise rates of 40 A/ns, 80 A/ns, and 120 A/ns are generated for investigating the influence of current rise rate on energy deposition. Experimental results show a significant increase of energy deposition into the wire before the voltage breakdown with the increase of current rise rate. The influence of wire dimension on energy deposition is investigated as well. Decreasing the wire length allows more energy to be deposited into the wire. The energy deposition of a 0.5 cm-long wire explosion is ∼2.5 times higher than the energy deposition of a 2 cm-long wire explosion. The dependence of the energy deposition on wire diameter demonstrates a maximum energy deposition of 2.7 eV/atom with a diameter of ∼18 μm. Substantial increase in energy deposition is observed in the electrical explosion of aluminum wire with polyimide coating. A laser probe is applied to construct the shadowgraphy, schlieren, and interferometry diagnostics. The morphology and expansion trajectory of exploding products are analyzed based on the shadowgram. The interference phase shift is reconstructed from the interferogram. Parallel dual wires are exploded to estimate the expansion velocity of the plasma shell.

  13. Photon Detection with Cooled Avalanche Photodiodes: Theory and Preliminary Experimental Results

    NASA Technical Reports Server (NTRS)

    Robinson, D. L.; Hays, D. A.

    1985-01-01

    Avalanche photodiodes (APDs) can be operated in a geiger-tube mode so that they can respond to single electron events and thus be used as photon counting detectors. Operational characteristics and theory of APDs while used in this mode are analyzed and assessed. Preliminary experimental investigation of several commercially available APDs has commenced, and initial results for dark count statistics are presented.

  14. At Odds: Reconciling Experimental and Theoretical Results in High School Physics

    ERIC Educational Resources Information Center

    Gates, Joshua

    2009-01-01

    For this experiment, students are divided into 2 groups and presented with a static equilibrium force-balance problem to solve. One group works entirely experimentally and the other group theoretically, using Newton's laws. The groups present their seemingly dissimilar results and must reconcile them through discussion. (Contains 3 figures.)

  15. Experimental results on time-resolved reflectance diffuse optical tomography with fast-gated SPADs

    NASA Astrophysics Data System (ADS)

    Puszka, Agathe; Di Sieno, Laura; Dalla Mora, Alberto; Pifferi, Antonio; Contini, Davide; Boso, Gianluca; Tosi, Alberto; Planat-Chrétien, Anne; Hervé, Lionel; Koenig, Anne; Dinten, Jean-Marc

    2013-06-01

    We present experimental results of time-resolved reflectance diffuse optical tomography performed with fast-gated single-photon avalanche diodes (SPADs) and show an increased imaged depth range for a given acquisition time compared to the non gated mode.

  16. Modeling the Fracturing of Rock by Fluid Injection - Comparison of Numerical and Experimental Results

    NASA Astrophysics Data System (ADS)

    Heinze, Thomas; Galvan, Boris; Miller, Stephen

    2013-04-01

    Fluid-rock interactions are mechanically fundamental to many earth processes, including fault zones and hydrothermal/volcanic systems, and to future green energy solutions such as enhanced geothermal systems and carbon capture and storage (CCS). Modeling these processes is challenging because of the strong coupling between rock fracture evolution and the consequent large changes in the hydraulic properties of the system. In this talk, we present results of a numerical model that includes poro-elastic plastic rheology (with hardening, softening, and damage), and coupled to a non-linear diffusion model for fluid pressure propagation and two-phase fluid flow. Our plane strain model is based on the poro- elastic plastic behavior of porous rock and is advanced with hardening, softening and damage using the Mohr- Coulomb failure criteria. The effective stress model of Biot (1944) is used for coupling the pore pressure and the rock behavior. Frictional hardening and cohesion softening are introduced following Vermeer and de Borst (1984) with the angle of internal friction and the cohesion as functions of the principal strain rates. The scalar damage coefficient is assumed to be a linear function of the hardening parameter. Fluid injection is modeled as a two phase mixture of water and air using the Richards equation. The theoretical model is solved using finite differences on a staggered grid. The model is benchmarked with experiments on the laboratory scale in which fluid is injected from below in a critically-stressed, dry sandstone (Stanchits et al. 2011). We simulate three experiments, a) the failure a dry specimen due to biaxial compressive loading, b) the propagation a of low pressure fluid front induced from the bottom in a critically stressed specimen, and c) the failure of a critically stressed specimen due to a high pressure fluid intrusion. Comparison of model results with the fluid injection experiments shows that the model captures most of the experimental

  17. Experimental investigations in particle physics at intermediate energies

    SciTech Connect

    Auerbach, L.B.; Highland, V.L.; Martoff, C.J.; McFarlane, K.W.; Guss, C.; Kettell, S.

    1991-09-30

    The major elements of this project continues to be on fundamental symmetries and parameters of the Standard Model. The projects in the current period have been BNL E791 (a search for the decay K{sub L}{sup 0} {yields} {mu}e, which would violate the rule of separate lepton number conservation), test of an upgrade proposal (E871), and LSND, a neutrino experiment at LAMPF. For E791, data taking was completed in June 1990, and preliminary results are now available for the decays K{sub L}{sup 0} {yields} {mu}e and K{sub L}{sup 0} {yields} {mu}{mu}from the entire data set. The data for decay K{sub L}{sup 0} {yields} ee are still being analysed. These are an upper limit for the branching fraction for K{sub L}{sup 0} {yields} {mu}e of 3.5 {times} 10{sup {minus}11} (90% C.L.). From the 1990 data alone, we have a new (preliminary) value of the branching fraction for K{sub L}{sup 0} {yields} {mu}{mu} of (6.96{plus minus}0. 4{plus minus}0.22) {times} 10{sup {minus}9}, with a sample of 349 events. Combining this with earlier data gives (6.96{plus minus}0.34) {times} 10{sup 9}, by far the most precise value. The limit on the decay K{sub L}{sup 0} {yields} {mu}e places a lower limit on the mass of a new particle mediating such decays of 85 TeV. The LSND (Large Scintillator Neutrino Detector), a search for neutrino oscillations at LAMPF, has been approved, and is now underway. Other neutrino work at Los Alamos, E764, has resulted in a final publication. This includes the best, measurement of {nu}-nuclear scattering, in {nu}{sub mu} {sup 12}C inclusive cross sections. The measurement of the cross section for the exclusive reaction {nu}{sup mu}{sup 12}C {yields} {mu}{sup {minus}12} N is unique. In a new development, Dr. Martoff has established a facility for fabrication of superconducting detectors of nuclear radiation; the equipment has been funded and is partly installed. Planned uses include scattering for Dark Matter.' In summary, the objectives for this year have been met.

  18. Theoretical study of alkali cation-benzene complexes: potential energy surfaces and binding energies with improved results for rubidium and cesium.

    PubMed

    Coletti, Cecilia; Re, Nazzareno

    2006-05-25

    High level ab initio quantum chemical calculations have been carried out on the binding of alkali metal to benzene with special attention to heavier metals for which the agreement between the most recent theoretical investigations and the experimental bond dissociation energies (BDEs) is not very good. We performed BSSE-corrected geometry optimizations employing the MP2 level of theory with large basis sets and a modified Stuttgart RSC 1997 basis set for rubidium and cesium and carried out single point energy calculations at the MP4 level, obtaining, also for the latter metals, BDE values in good agreement with the experimental results. Furthermore, in view of the development of empirical correction terms to force fields to describe cation-pi interactions, we evaluated the potential energy surface along the benzene symmetry axis and discussed the role of the BSSE correction on the accuracy of our results.

  19. Au Lα x-rays induced by photons from 241Am: Comparison of experimental results and the predictions of PENELOPE.

    PubMed

    Gonzales, D; Requena, S; Williams, S

    2012-01-01

    The results of experiments performed, measuring the Lα x-rays emitted by Au due to excitation by photons of various energies from an (241)Am sample at forward-scattered angles in the range 0° to 65°, are compared to the predictions of the Monte Carlo code, PENELOPE. The experimental data are in good agreement with the predictions of the program. A comparison of the angular distributions of the probability densities (as predicted by the program) related to the Au Lα and Lβ x-rays suggests that PENELOPE does not simulate the phenomena described by Flügge et al. (1972).

  20. Design and experimental results for a flapped natural-laminar-flow airfoil for general aviation applications

    NASA Technical Reports Server (NTRS)

    Somers, D. M.

    1981-01-01

    A flapped natural laminar flow airfoil for general aviation applications, the NLF(1)-0215F, has been designed and analyzed theoretically and verified experimentally in the Langley Low Turbulence Pressure Tunnel. The basic objective of combining the high maximum lift of the NASA low speed airfoils with the low cruise drag of the NACA 6 series airfoils has been achieved. The safety requirement that the maximum lift coefficient not be significantly affected with transition fixed near the leading edge has also been met. Comparisons of the theoretical and experimental results show generally good agreement.

  1. Design and Experimental Results for a Natural-Laminar-Flow Airfoil for General Aviation Applications

    NASA Technical Reports Server (NTRS)

    Somers, D. M.

    1981-01-01

    A natural-laminar-flow airfoil for general aviation applications, the NLF(1)-0416, was designed and analyzed theoretically and verified experimentally in the Langley Low-Turbulence Pressure Tunnel. The basic objective of combining the high maximum lift of the NASA low-speed airfoils with the low cruise drag of the NACA 6-series airfoils was achieved. The safety requirement that the maximum lift coefficient not be significantly affected with transition fixed near the leading edge was also met. Comparisons of the theoretical and experimental results show excellent agreement. Comparisons with other airfoils, both laminar flow and turbulent flow, confirm the achievement of the basic objective.

  2. Report on Research in Experimental High Energy Physics

    SciTech Connect

    Rusack, Roger W.; Cushman, Priscilla; Poling, Ronald

    2016-01-06

    In the past three years the groups supported by the DOE have all made significant progress and posted major successes. The Minnesota CMS group has played leading roles in five data analyses and has had major roles in detector operations, the data management and the detector upgrades that are planned for for the LHC and those that are planned for the high-luminosity LHC. The CDMS-II experiment held the lead in WIMP sensitivity over the last decade, and is still the most sensitive detector in the world in the low WIMP mass region, with a recent 3σ hint of 8 GeV/c2 WIMP candidates in the silicon data. SuperCDMS, with three orders of magnitude better electron recoil background rejection, has been collecting data since October 2011. Since all dark matter experiments require a better understanding of neutron backgrounds to make further advances in sensitivity, Cushman has expanded the Minnesota effort on backgrounds to the national level, where she is leading a coordinated effort in neutron simulations for underground physics. The work of Mandic on 100 mm detectors both for Super-CDMS and beyond has advanced rapidly. Also at the Intensity Frontier, the BESIII experiment has had a successful year of operation largely focused on searches for and studies of new "charmonium-like" states above DD threshold. At least one new state has been observed so far, with hints of others. An intensive effort to understand their nature and gain new insight into the strong interaction continues. BESIII has also produced a large number of other results in charmonium decay and light-hadronic physics.

  3. Laminar counterflow spray diffusion flames: A comparison between experimental results and complex chemistry calculations

    SciTech Connect

    Darabiha, N.; Lacas, F.; Rolon, J.C.; Candel, S. . Lab. EM2C)

    1993-11-01

    Experimental and numerical studies of laminar flames formed by the counterflow of a monodisperse fuel spray with an air stream are reported in this article. In this simple configuration it is possible to analyze the influence of the phase transfer terms on the flame structure. The experimental setup used to produce such laminar spray diffusion flames is first described. A set of experiments are carried with liquid heptane fuel sprays. The flame is characterized with a laser sheet imaging system and with a particle sizing apparatus based on laser light diffraction. Results of a numerical study are then presented. The two phase-reacting flow equations are solved through Newton iterations and adaptive gridding using detailed transport and complex chemistry. An iterative procedure is devised to solve the gas- and liquid-phase balance equations. Comparison between experimental and numerical values of the diameter are found to be in good agreement.

  4. Numerical and experimental assessment of turbulent kinetic energy in an aortic coarctation.

    PubMed

    Lantz, Jonas; Ebbers, Tino; Engvall, Jan; Karlsson, Matts

    2013-07-26

    The turbulent blood flow through an aortic coarctation in a 63-year old female patient was studied experimentally using magnetic resonance imaging (MRI), and numerically using computational fluid dynamics (CFD), before and after catheter intervention. Turbulent kinetic energy (TKE) was computed in the numerical model using large eddy simulation and compared with direct in vivo MRI measurements. Despite the two totally different methods to obtain TKE values, both quantitative and qualitative results agreed very well. The results showed that even though both blood flow rate and Reynolds number increased after intervention, total turbulent kinetic energy levels decreased in the coarctation. Therefore, the use of the Reynolds number alone as a measure of turbulence in cardiovascular flows should be used with caution. Furthermore, the change in flow field and kinetic energy were assessed, and it was found that before intervention a jet formed in the throat of the coarctation, which impacted the arterial wall just downstream the constriction. After intervention the jet was significantly weaker and broke up almost immediately, presumably resulting in less stress on the wall. As there was a good agreement between measurements and numerical results (the increase and decrease of integrated TKE matched measurements almost perfectly while peak values differed by approximately 1mJ), the CFD results confirmed the MRI measurements while at the same time providing high-resolution details about the flow. Thus, this preliminary study indicates that MR-based TKE measurements might be useful as a diagnostic tool when evaluating intervention outcome, while the detailed numerical results might be useful for further understanding of the flow for treatment planning.

  5. Model for energy transfer in the solar wind: Model results

    NASA Technical Reports Server (NTRS)

    Barnes, A. A., Jr.; Hartle, R. E.

    1972-01-01

    A description is given of the results of solar wind flow in which the heating is due to (1) propagation and dissipation of hydromagnetic waves generated near the base of the wind, and (2) thermal conduction. A series of models is generated for fixed values of density, electron and proton temperature, and magnetic field at the base by varying the wave intensity at the base of the model. This series of models predicts the observed correlation between flow speed and proton temperature for a large range of velocities. The wave heating takes place in a shell about the sun greater than or approximately equal to 10 R thick. We conclude that large-scale variations observed in the solar wind are probably due mainly to variation in the hydromagnetic wave flux near the sun.

  6. Experimental energy consumption of Frame Slotted ALOHA and Distributed Queuing for data collection scenarios.

    PubMed

    Tuset-Peiro, Pere; Vazquez-Gallego, Francisco; Alonso-Zarate, Jesus; Alonso, Luis; Vilajosana, Xavier

    2014-07-24

    Data collection is a key scenario for the Internet of Things because it enables gathering sensor data from distributed nodes that use low-power and long-range wireless technologies to communicate in a single-hop approach. In this kind of scenario, the network is composed of one coordinator that covers a particular area and a large number of nodes, typically hundreds or thousands, that transmit data to the coordinator upon request. Considering this scenario, in this paper we experimentally validate the energy consumption of two Medium Access Control (MAC) protocols, Frame Slotted ALOHA (FSA) and Distributed Queuing (DQ). We model both protocols as a state machine and conduct experiments to measure the average energy consumption in each state and the average number of times that a node has to be in each state in order to transmit a data packet to the coordinator. The results show that FSA is more energy efficient than DQ if the number of nodes is known a priori because the number of slots per frame can be adjusted accordingly. However, in such scenarios the number of nodes cannot be easily anticipated, leading to additional packet collisions and a higher energy consumption due to retransmissions. Contrarily, DQ does not require to know the number of nodes in advance because it is able to efficiently construct an ad hoc network schedule for each collection round. This kind of a schedule ensures that there are no packet collisions during data transmission, thus leading to an energy consumption reduction above 10% compared to FSA.

  7. Experimental Energy Consumption of Frame Slotted ALOHA and Distributed Queuing for Data Collection Scenarios

    PubMed Central

    Tuset-Peiro, Pere; Vazquez-Gallego, Francisco; Alonso-Zarate, Jesus; Alonso, Luis; Vilajosana, Xavier

    2014-01-01

    Data collection is a key scenario for the Internet of Things because it enables gathering sensor data from distributed nodes that use low-power and long-range wireless technologies to communicate in a single-hop approach. In this kind of scenario, the network is composed of one coordinator that covers a particular area and a large number of nodes, typically hundreds or thousands, that transmit data to the coordinator upon request. Considering this scenario, in this paper we experimentally validate the energy consumption of two Medium Access Control (MAC) protocols, Frame Slotted ALOHA (FSA) and Distributed Queuing (DQ). We model both protocols as a state machine and conduct experiments to measure the average energy consumption in each state and the average number of times that a node has to be in each state in order to transmit a data packet to the coordinator. The results show that FSA is more energy efficient than DQ if the number of nodes is known a priori because the number of slots per frame can be adjusted accordingly. However, in such scenarios the number of nodes cannot be easily anticipated, leading to additional packet collisions and a higher energy consumption due to retransmissions. Contrarily, DQ does not require to know the number of nodes in advance because it is able to efficiently construct an ad hoc network schedule for each collection round. This kind of a schedule ensures that there are no packet collisions during data transmission, thus leading to an energy consumption reduction above 10% compared to FSA. PMID:25061839

  8. Automated detection of discourse segment and experimental types from the text of cancer pathway results sections

    PubMed Central

    Burns, Gully A.P.C.; Dasigi, Pradeep; de Waard, Anita; Hovy, Eduard H.

    2016-01-01

    Automated machine-reading biocuration systems typically use sentence-by-sentence information extraction to construct meaning representations for use by curators. This does not directly reflect the typical discourse structure used by scientists to construct an argument from the experimental data available within a article, and is therefore less likely to correspond to representations typically used in biomedical informatics systems (let alone to the mental models that scientists have). In this study, we develop Natural Language Processing methods to locate, extract, and classify the individual passages of text from articles’ Results sections that refer to experimental data. In our domain of interest (molecular biology studies of cancer signal transduction pathways), individual articles may contain as many as 30 small-scale individual experiments describing a variety of findings, upon which authors base their overall research conclusions. Our system automatically classifies discourse segments in these texts into seven categories (fact, hypothesis, problem, goal, method, result, implication) with an F-score of 0.68. These segments describe the essential building blocks of scientific discourse to (i) provide context for each experiment, (ii) report experimental details and (iii) explain the data’s meaning in context. We evaluate our system on text passages from articles that were curated in molecular biology databases (the Pathway Logic Datum repository, the Molecular Interaction MINT and INTACT databases) linking individual experiments in articles to the type of assay used (coprecipitation, phosphorylation, translocation etc.). We use supervised machine learning techniques on text passages containing unambiguous references to experiments to obtain baseline F1 scores of 0.59 for MINT, 0.71 for INTACT and 0.63 for Pathway Logic. Although preliminary, these results support the notion that targeting information extraction methods to experimental results could provide

  9. The Energy Balance Study: The Design and Baseline Results for a Longitudinal Study of Energy Balance

    ERIC Educational Resources Information Center

    Hand, Gregory A.; Shook, Robin P.; Paluch, Amanda E.; Baruth, Meghan; Crowley, E. Patrick; Jaggers, Jason R.; Prasad, Vivek K.; Hurley, Thomas G.; Hebert, James R.; O'Connor, Daniel P.; Archer, Edward; Burgess, Stephanie; Blair, Steven N.

    2013-01-01

    Purpose: The Energy Balance Study (EBS) was a comprehensive study designed to determine over a period of 12 months the associations of caloric intake and energy expenditure on changes in body weight and composition in a population of healthy men and women. Method: EBS recruited men and women aged 21 to 35 years with a body mass index between 20…

  10. Experimental Energy Levels of HD18O and D_218O

    NASA Astrophysics Data System (ADS)

    Mikhailenko, S. N.; Naumenko, O. V.; Tashkun, S. A.; Liu, A.-W.; Hu, S.-M.

    2010-06-01

    Extended sets of experimental energy levels of HD18O and D_218O have been obtained as the result of the analysis of recent high-resolution spectra and previously reported data. Spectra of the enriched by deuterium and oxygen-18 water samples were recorded with a Bruker IFS 120HR spectrometer at room temperature in the 1000 - 9200 cm-1 range a,b for this purpose. The RITZ code h was used for analysis of the rotation-vibration transitions and the energy levels determination. New energy levels as well as comparison with previous experimental and theoretical studies will be presented. This work was supported by Grant nos. 06-03-39014 and 10-05-91176 of RFBR (Russia) and by Grant nos. 20903085 and 10574124 of NSFC (China). Work of SNM and SAT was also partly supported by CRDF (USA) Grant RUG1-2954-TO-09 and by RFBR. Grant 09-05-92508. A.-W. Liu et al., J. Mol. Spectrosc. 237, 149-162 (2006). H.-Y. Ni et al., Mol. Phys. 106, 1793-1801 (2008). J. Bellet et al., J. Mol. Spectrosc. 47, 388-402 (1973). J.W.C. Johns, J. Opt. Soc. Am. B2, 1340-1354 (1985). R.A. Toth, J. Mol. Spectrosc. 162, 41-54 (1993). W.F. Wang et al., J. Mol. Spectrosc. 176, 226-228 (1996). R.A. Toth, J. Mol. Structure, 742, 49-68 (2005). S.N. Mikhailenko et al., JQSRT, 110, 597-608 (2009). A. Liu et al., JQSRT, 110, 1781-1800 (2009). O.V. Naumenko et al., JQSRT, 111, 36-44 (2010).

  11. Distributions of experimental protein structures on coarse-grained free energy landscapes

    NASA Astrophysics Data System (ADS)

    Sankar, Kannan; Liu, Jie; Wang, Yuan; Jernigan, Robert L.

    2015-12-01

    Predicting conformational changes of proteins is needed in order to fully comprehend functional mechanisms. With the large number of available structures in sets of related proteins, it is now possible to directly visualize the clusters of conformations and their conformational transitions through the use of principal component analysis. The most striking observation about the distributions of the structures along the principal components is their highly non-uniform distributions. In this work, we use principal component analysis of experimental structures of 50 diverse proteins to extract the most important directions of their motions, sample structures along these directions, and estimate their free energy landscapes by combining knowledge-based potentials and entropy computed from elastic network models. When these resulting motions are visualized upon their coarse-grained free energy landscapes, the basis for conformational pathways becomes readily apparent. Using three well-studied proteins, T4 lysozyme, serum albumin, and sarco-endoplasmic reticular Ca2+ adenosine triphosphatase (SERCA), as examples, we show that such free energy landscapes of conformational changes provide meaningful insights into the functional dynamics and suggest transition pathways between different conformational states. As a further example, we also show that Monte Carlo simulations on the coarse-grained landscape of HIV-1 protease can directly yield pathways for force-driven conformational changes.

  12. Experimental Performance Analysis of Supercritical CO2 Thermodynamic Cycle Powered by Solar Energy

    NASA Astrophysics Data System (ADS)

    Zhang, X. R.; Yamaguchi, H.; Fujima, K.; Enomoto, M.; Sawada, N.

    2006-05-01

    The interests in using carbon dioxide as working fluid increase since the Montreal and Kyoto Protocols were made. In this paper, a complete effort was made to study the performance of CO2 Rankine cycle powered by solar energy experimentally. The system utilizes evacuated solar collectors to convert CO2 into high-temperature supercritical state, used to produce electrical energy and thermal energy, which could be used for air conditioning and hot water supply and so on. The system performances were tested not only in summer, but also in winter; not only in sunny day, but also in cloudy day. The interest of the paper is the solar collector efficiency, because the absorbed heat quantity in the collector can be utilized for power generation and heat supply and other useful outputs. The results show that annually-averaged solar collector efficiency was measured at about 60.4%. The study shows the potential of the application of the solar powered CO2 cycle as a distributed power/heat generation system.

  13. Wave spectra of a shoaling wave field: A comparison of experimental and simulated results

    NASA Technical Reports Server (NTRS)

    Morris, W. D.; Grosch, C. E.; Poole, L. R.

    1982-01-01

    Wave profile measurements made from an aircraft crossing the North Carolina continental shelf after passage of Tropical Storm Amy in 1975 are used to compute a series of wave energy spectra for comparison with simulated spectra. Results indicate that the observed wave field experiences refraction and shoaling effects causing statistically significant changes in the spectral density levels. A modeling technique is used to simulate the spectral density levels. Total energy levels of the simulated spectra are within 20 percent of those of the observed wave field. The results represent a successful attempt to theoretically simulate, at oceanic scales, the decay of a wave field which contains significant wave energies from deepwater through shoaling conditions.

  14. Propagation effects for land mobile satellite systems: Overview of experimental and modeling results

    NASA Technical Reports Server (NTRS)

    Goldhirsh, Julius; Vogel, Wolfhard J.

    1992-01-01

    Models developed and experiments performed to characterize the propagation environment associated with land mobile communication using satellites are discussed. Experiments were carried out with transmitters on stratospheric balloons, remotely piloted aircraft, helicopters, and geostationary satellites. This text is comprised of compiled experimental results for the expressed use of communications engineers, designers of planned Land Mobile Satellite Systems (LMSS), and modelers of propagation effects. The results presented here are mostly derived from systematic studies of propagation effects for LMSS geometries in the United States associated with rural and suburban regions. Where applicable, the authors also draw liberally from the results of other related investigations in Canada, Europe, and Australia. Frequencies near 1500 MHz are emphasized to coincide with frequency bands allocated for LMSS by the International Telecommunication Union, although earlier experimental work at 870 MHz is also included.

  15. Propagation effects for land mobile satellite systems: Overview of experimental and modeling results

    NASA Astrophysics Data System (ADS)

    Goldhirsh, Julius; Vogel, Wolfhard J.

    1992-02-01

    Models developed and experiments performed to characterize the propagation environment associated with land mobile communication using satellites are discussed. Experiments were carried out with transmitters on stratospheric balloons, remotely piloted aircraft, helicopters, and geostationary satellites. This text is comprised of compiled experimental results for the expressed use of communications engineers, designers of planned Land Mobile Satellite Systems (LMSS), and modelers of propagation effects. The results presented here are mostly derived from systematic studies of propagation effects for LMSS geometries in the United States associated with rural and suburban regions. Where applicable, the authors also draw liberally from the results of other related investigations in Canada, Europe, and Australia. Frequencies near 1500 MHz are emphasized to coincide with frequency bands allocated for LMSS by the International Telecommunication Union, although earlier experimental work at 870 MHz is also included.

  16. Predictions of the equation of state of cerium yield interesting insights into experimental results

    SciTech Connect

    Cherne, Frank J; Jensen, Brian J; Rigg, Paulo A; Elkin, Vyacheslav M

    2009-01-01

    There has been much interest in the past in understanding the dynamic properties of phase changing materials. In this paper we begin to explore the dynamic properties of the complex material of cerium. Cerium metal is a good candidate material to explore capabilities in determining a dynamic phase diagram on account of its low dynamic phase boundaries, namely, the {gamma}-{alpha}, and {alpha}-liquid phase boundaries. Here we present a combination of experimental results with calculated results to try to understand the dynamic behavior of the material. Using the front surface impact technique, we performed a series of experiments which displayed a rarefaction shock upon release. These experiments show that the reversion shock stresses occur at different magnitudes, allowing us to plot out the {gamma}-{alpha} phase boundary. Applying a multiphase equation of state a broader understanding of the experimental results will be discussed.

  17. Numerical predictions and experimental results of a dry bay fire environment.

    SciTech Connect

    Suo-Anttila, Jill Marie; Gill, Walter; Black, Amalia Rebecca

    2003-11-01

    The primary objective of the Safety and Survivability of Aircraft Initiative is to improve the safety and survivability of systems by using validated computational models to predict the hazard posed by a fire. To meet this need, computational model predictions and experimental data have been obtained to provide insight into the thermal environment inside an aircraft dry bay. The calculations were performed using the Vulcan fire code, and the experiments were completed using a specially designed full-scale fixture. The focus of this report is to present comparisons of the Vulcan results with experimental data for a selected test scenario and to assess the capability of the Vulcan fire field model to accurately predict dry bay fire scenarios. Also included is an assessment of the sensitivity of the fire model predictions to boundary condition distribution and grid resolution. To facilitate the comparison with experimental results, a brief description of the dry bay fire test fixture and a detailed specification of the geometry and boundary conditions are included. Overall, the Vulcan fire field model has shown the capability to predict the thermal hazard posed by a sustained pool fire within a dry bay compartment of an aircraft; although, more extensive experimental data and rigorous comparison are required for model validation.

  18. IFNAR signaling directly modulates T lymphocyte activity, resulting in milder experimental autoimmune encephalomyelitis development

    PubMed Central

    Kavrochorianou, Nadia; Evangelidou, Maria; Markogiannaki, Melina; Tovey, Michael; Thyphronitis, George; Haralambous, Sylva

    2016-01-01

    Although interferon-β is used as first-line therapy for multiple sclerosis, the cell type-specific activity of type I interferons in multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis, remains obscure. In this study, we have elucidated the in vivo immunomodulatory role of type I interferon signaling in T cells during experimental autoimmune encephalomyelitis by use of a novel transgenic mouse, carrying a cd2–ifnar1 transgene on a interferon-α/β receptor 1 null genetic background, thus allowing expression of the interferon-α/β receptor 1 and hence, a functional type I interferon receptor exclusively on T cells. These transgenic mice exhibited milder experimental autoimmune encephalomyelitis with reduced T cell infiltration, demyelination, and axonal damage in the central nervous system. It is noteworthy that interferon-β administration in transgenic mice generated a more pronounced, protective effect against experimental autoimmune encephalomyelitis compared with untreated littermates. In vivo studies demonstrated that before experimental autoimmune encephalomyelitis onset, endogenous type I interferon receptor signaling in T cells led to impaired T-helper 17 responses, with a reduced fraction of CCR6+ CD4+ T cells in the periphery. At the acute phase, an increased proportion of interleukin-10- and interferon-γ-producing CD4+ T cells was detected in the periphery of the transgenic mice, accompanied by up-regulation of the interferon-γ-induced gene Irgm1 in peripheral T cells. Together, these results reveal a hitherto unknown T cell-associated protective role of type I interferon in experimental autoimmune encephalomyelitis that may provide valuable clues for designing novel therapeutic strategies for multiple sclerosis. PMID:26232452

  19. OVERVIEW OF RECENT EXPERIMENTAL RESULTS FROM THE DIII-D ADVANCED TOKAMAK PROGRAM

    SciTech Connect

    BURRELL,HK

    2002-11-01

    OAK A271 OVERVIEW OF RECENT EXPERIMENTAL RESULTS FROM THE DIII-D ADVANCED TOKAMAK PROGRAM. The DIII-D research program is developing the scientific basis for advanced tokamak (AT) modes of operation in order to enhance the attractiveness of the tokamak as an energy producing system. Since the last International Atomic Energy Agency (IAEA) meeting, they have made significant progress in developing the building blocks needed for AT operation: (1) they have doubled the magnetohydrodynamic (MHD) stable tokamak operating space through rotational stabilization of the resistive wall mode; (2) using this rotational stabilization, they have achieved {beta}{sub N}H{sub 89} {ge} 10 for 4 {tau}{sub E} limited by the neoclassical tearing mode; (3) using real-time feedback of the electron cyclotron current drive (ECCD) location, they have stabilized the (m,n) = (3,2) neoclassical tearing mode and then increased {beta}{sub T} by 60%; (4) they have produced ECCD stabilization of the (2,1) neoclassical tearing mode in initial experiments; (5) they have made the first integrated AT demonstration discharges with current profile control using ECCD; (6) ECCD and electron cyclotron heating (ECH) have been used to control the pressure profile in high performance plasmas; and (7) they have demonstrated stationary tokamak operation for 6.5 s (36 {tau}{sub E}) at the same fusion gain parameter of {beta}{sub N}H{sub 89}/q{sub 95}{sup 2} {approx} 0.4 as ITER but at much higher q{sub 95} = 4.2. The authors have developed general improvements applicable to conventional and advanced tokamak operating modes: (1) they have an existence proof of a mode of tokamak operation, quiescent H-mode, which has no pulsed, ELM heat load to the divertor and which can run for long periods of time (3.8 s or 25 {tau}{sub E}) with constant density and constant radiated power; (2) they have demonstrated real-time disruption detection and mitigation for vertical disruption events using high pressure gas jet

  20. Experimental investigation of ≈130 keV kinetic energy antiprotons annihilation on nuclei

    NASA Astrophysics Data System (ADS)

    Aghai-Khozani, H.; Barna, D.; Corradini, M.; Hayano, R.; Hori, M.; Kobayashi, T.; Leali, M.; Lodi-Rizzini, E.; Mascagna, V.; Prest, M.; Soter, A.; Todoroki, K.; Vallazza, E.; Venturelli, L.; Zurlo, N.

    2014-04-01

    The study of the antiproton ( bar {p}) annihilation cross section on nuclei at low energies (eV-MeV region) has implications for fundamental cosmology as well as for nuclear physics. Concerning the former, different models try to explain the matter/antimatter asymmetry in the universe assuming the existence of the so-called "islands" where antinucleon-nucleon annihilations occur in the border region (Cohen et al. Astrophys. J. 495, 539-549, 1998), while, from the nuclear physics point of view, the annihilation process is a valuable tool to evaluate the neutron/proton ratio in order to probe the external region of the nucleus (Gupta et al. Nucl. Phys. B 70(3), 414-424, 1974). The existing data of antinucleon-nucleon (or -nucleus) annihilation cross-sections are mainly confined to energies above ≈1 MeV, while the cross section measured at LEAR in the 80's-90's (mostly with light targets Agnello et al. Phys. Lett. B 256, 349-353, 1991; Bertin et al. Phys. Lett. B 369, 77-85, 1996; Bertin et al. Phys. Lett. B 414, 220-228, 1997; Zenoni et al. Phys. Lett. B 461, 405-412, 1999; Bianconi et al. Phys. Lett. B 481, 194-198, 2000; Bianconi et al. Phys. Lett. B 492, 254-258, 2000) showed an unexpected behaviour for energies below 1 MeV (Bianconi et al. Phys. Lett. B 483, 353-359, 2000; Bianconi et al. Phys. Rev. C 62, 014611-7, 2000; Batty et al. Nucl. Phys. A 689, 721-740, 2001). The results showed a saturation with the atomic mass number against the A 2/3 trend which is observed for higher energies (being A the target mass number). The ASACUSA collaboration at CERN recently measured antiproton annihilation cross section on different kinds of nuclei with a bar {p} kinetic energy of 5.3 MeV (Bianconi et al. Phys. Lett. B 704, 461-466, 2011; Corradini et al. Nucl. Instr. Methods A 711, 12-20, 2013). Such results proved compatibility with the black-disk model with the Coulomb correction. But till now experimental difficulties prevented the investigation at energies below ≈1

  1. Corrosion by liquid lead and lead-bismuth: experimental results review and analysis

    SciTech Connect

    Zhang, Jinsuo

    2008-01-01

    Liquid metal technologies for liquid lead and lead-bismuth alloy are under wide investigation and development for advanced nuclear energy systems and waste transmutation systems. Material corrosion is one of the main issues studied a lot recently in the development of the liquid metal technology. This study reviews corrosion by liquid lead and lead bismuth, including the corrosion mechanisms, corrosion inhibitor and the formation of the protective oxide layer. The available experimental data are analyzed by using a corrosion model in which the oxidation and scale removal are coupled. Based on the model, long-term behaviors of steels in liquid lead and lead-bismuth are predictable. This report provides information for the selection of structural materials for typical nuclear reactor coolant systems when selecting liquid lead or lead bismuth as heat transfer media.

  2. Investigation of superelastic electron scattering by laser-excited Ba - Experimental procedures and results

    NASA Technical Reports Server (NTRS)

    Register, D. F.; Trajmar, S.; Fineman, M. A.; Poe, R. T.; Csanak, G.; Jensen, S. W.

    1983-01-01

    Differential (in angle) electron scattering experiments on laser-excited Ba-138 1P were carried out at 30- and 100-eV impact energies. The laser light was linearly polarized and located in the scattering plane. The superelastic scattering signal was measured as a function of polarization direction of the laser light with respect to the scattering plane. It was found at low electron scattering angles that the superelastic scattering signal was asymmetric to reflection of the polarization vector with respect to the scattering plane. This is in contradiction with theoretical predictions. An attempt was made to pinpoint the reason for this observation, and a detailed investigation of the influence of experimental conditions on the superelastic scattering was undertaken. No explanation for the asymmetry has as yet been found.

  3. Beta decay and the origin of biologial chirality - New experimental results

    NASA Technical Reports Server (NTRS)

    Van House, J.; Rich, A.; Zitzewitz, P. W.

    1984-01-01

    The hypothetical connection developed by Vester and Ulbricht (1959), between the handedness of beta particles in radioactive decay and the (L) sign of biologial chirality is investigated in a radiolysis experiment. The experiment measured the predicted asymmetry in the formation triplet or 'ortho-' positronium (oPs) in amino acid enantiomers by low energy positrons under conditions of helicity reversal. The positrons were focused on amino acid powder samples. By measuring the time between positron arrival and emission of gamma rays, long-lived oPs were separated from other species. It is found that the asymmetry in leucine (0.8 x 10 to the -4th) is consistent with the theoretical prediction of 10 to the -6th. Neither the experimental limits nor the theoretical estimates are found to rule out a mechanism like that described by Vester and Ulbricht as the cause of the sign of the observed chiral polarization.

  4. Experimental results from a DC photocathode electron gun for an IR FEL

    SciTech Connect

    Kehne, D.; Engwall, D.; Legg, R.; Shinn, M.

    1997-10-01

    A 350 keV DC photocathode gun capable of delivering the high-brightness CW electron beam necessary for Jefferson Lab`s infrared free-electron laser is described. The gun is to be used with a superconducting radiofrequency linac operating at 1.497 GHz and is mode-locked to the 40th subharmonic of the fundamental using a Nd:YLF drive laser. The gun provides 20--25 ps bunches at up to 135 pC/bunch. Experimental measurements of transverse and longitudinal beam properties are presented. Transverse emittance is measured using a slit-wire scanner emittance meter, and energy spread is measured using the slit and a spectrometer magnet. Longitudinal emittance is measured using a combination of sampling aperture, kicker cavity, slit and spectrometer. Measurements for bunch charges of 135 pC are described and compared with simulations.

  5. Real-time measurements of D/log-E curves in holographic emulsions: experimental results

    NASA Astrophysics Data System (ADS)

    Fimia, Antonio; Blaya-Escarre, Salvador; Carretero-Lopez, Luis; Madrigal, Roque F.; Mallavia, Ricardo M.

    1999-03-01

    The response curve D-Log E is the most important method to characterize photographic emulsions. In this work we present the experimental study using a real time technique that can be applied to the improvement of the holographic properties of emulsions. We have exposured an Agfa Gevaert 8E56HD emulsion with an Argon laser tuned at 514 nm. After it, we measured the transmittance curve when the emulsion was into the developer bath function of time at 20 degrees Celsius. This method gives us the possibility of study the dynamics of different developers as a function of the storage energy. It also provides a way to optimize the composition of developers function of the chemical composition, temperature and other secondary factors as superaditivity and non-linear processes.

  6. Importance of dose-rate and cell proliferation in the evaluation of biological experimental results

    NASA Technical Reports Server (NTRS)

    Curtis, S. B.

    1994-01-01

    The nuclei of cells within the bodies of astronauts traveling on extended missions outside the geomagnetosphere will experience single traversals of particles with high Linear Energy Transfer (LET) (e.g., one iron ion per one hundred years, on average) superimposed on a background of tracks with low LET (approximately one proton every two to three days, and one helium ion per month). In addition, some cell populations within the body will be proliferating, thus possibly providing increasing numbers of cells with 'initiated' targets for subsequent radiation hits. These temporal characteristics are not generally reproduced in laboratory experimental protocols. Implications of the differences in the temporal patterns of radiation delivery between conventionally designed radiation biology experiments and the pattern to be experienced in space are examined and the importance of dose-rate and cell proliferation are pointed out in the context of radiation risk assessment on long mission in space.

  7. An experimental investigation of energy transmission from an evanescent to a propagating region

    NASA Astrophysics Data System (ADS)

    Lee, Allison; Crockett, Julie

    2016-11-01

    Tidal flow over oceanic bathymetry is a well known generator of internal waves. However, in the deep ocean there are many regions of weak stratification and the tides will generate only evanescent waves which decay exponentially as they propagate away from their source. In locations where stronger stratification exists above the weak, evanescent waves can form propagating internal waves as they approach a depth with a stratification corresponding to their frequency (turning depth). An experimental study of the energy transfer from evanescent regions to propagating regions due to evanescent waves passing through a turning depth is presented. The effects of varying exponential stratification profiles and single and multi-peak topographical features are described and results are compared with linear theory approximations.

  8. New method of the polymeric material properties experimental investigation under powerful energy flux impact

    NASA Astrophysics Data System (ADS)

    Demidov, B. A.; Efremov, V. P.; Kalinin, Yu G.; Kazakov, E. D.; Metelkin, S. Yu; Petrov, V. A.; Potapenko, A. I.

    2015-11-01

    Investigation of the polymeric material properties under powerfull energy flux impact is relevant as for basic research (mathematical modeling of polymeric materials behavior in extreme conditions, testing the state equations), as for practical applications (for testing of protective coatings for space research and laboratory facilities). This paper presents the results of experimental studies of the interaction of polymeric materials with a relativistic electron beam produced by a high-current electron accelerator Calamary. Calamary facility provides a wide range of electron beam parameters: diameter 10-15 mm, the voltage on the diode up to 300 kV, the current through the diode up to 30 kA. New method of beam-target interaction area measurement was developed. The original method for the mechanical kick impulse measuring based on piezoelectric vibration sensor was presented. The dependence of the kick impulse from the power flux was obtained.

  9. Experimental Studies of Low Energy Proton Irradiation of Thin Vacuum Deposited Aluminum Layers

    NASA Astrophysics Data System (ADS)

    Renger, Thomas; Sznajder, Maciej; Geppert, Ulrich

    2014-06-01

    We present experimental studies of degradation effects caused by low energetic proton irradiation on thin Aluminum layers. The studies were performed by use the Complex Irradiation Facility (CIF) at the German Aerospace Center (DLR) in Bremen, Germany. Different proton doses and energies at two temperature levels of the samples were considered.The result of the irradiation tests is a formation of bubbles at the Aluminum surface. They are filled with molecular Hydrogen gas, which is created by the recombination processes of the metal free electrons and the incident protons. The average size of the bubbles increases with higher proton doses. As a consequence of the effect the metallic surface morphology is changed significantly.

  10. Controls-structures interaction guest investigator program: Overview and phase 1 experimental results and future plans

    NASA Technical Reports Server (NTRS)

    Smith-Taylor, Rudeen; Tanner, Sharon E.

    1993-01-01

    The NASA Controls-Structures Interaction (CSI) Guest Investigator program is described in terms of its support of the development of CSI technologies. The program is based on the introduction of CSI researchers from industry and academia to available test facilities for experimental validation of technologies and methods. Phase 1 experimental results are reviewed with attention given to their use of the Mini-MAST test facility and the facility for the Advance Control Evaluation of Structures. Experiments were conducted regarding the following topics: collocated/noncollocated controllers, nonlinear math modeling, controller design, passive/active suspension systems design, and system identification and fault isolation. The results demonstrate that significantly enhanced performance from the control techniques can be achieved by integrating knowledge of the structural dynamics under consideration into the approaches.

  11. Gradual ordering in mollusk shell nacre: theoretical modeling and experimental results

    NASA Astrophysics Data System (ADS)

    Coppersmith, Susan N.

    2013-03-01

    Biominerals have attracted the attention of materials scientists, biologists, and mineralogists as well as physicists because of their remarkable mechanical properties and incompletely elucidated formation mechanisms. Nacre, or mother-of-pearl, is a layered biomineral composite that is widely studied because of its self-assembled, efficient and accurately ordered architecture results in remarkable resistance to fracture. New experimental tools enable us to obtain new information about the organization and structure of the mineral tablets in nacre. Our experimental and theoretical investigations yield strong evidence that orientational ordering of these tablets is the result of dynamical self-organization. This work was supported by NSF award CHE&DMR-0613972, DOE award DE-FG02-07ER15899, UW-Graduate School Vilas Award to P.U.P.A. Gilbert, and NSF awards DMR-0209630 and DMR-0906951 to SNC.

  12. REFLECTIONS ON MY CONTRIBUTIONS TO PARTICLE PHYSICS AND RECENT EXPERIMENTAL RESULTS FROM RHIC.

    SciTech Connect

    SAMIOS,N.P.

    2002-01-18

    My talk today will be composed of two parts. The first part will consist of a summary of some of my experimental contributions over the years. It will not be exhaustive but will highlight the findings that had relevance to the progress of our understanding of particle physics as it has evolved over the years. This section will be divided into three periods: Early, Intermediate and Late, with an in depth discussion of a few of the more significant results. The second part will consist of a discussion of the recently completed Relativistic Heavy Ion Collider (RHIC) machine at Brookhaven National Laboratory (BNL). This will encompass the parameters of the accelerator and some of the interesting and exciting early experimental results emanating from this machine.

  13. Experimental results of the variable speed, direct drive multipole synchronous wind turbine TWT1650

    NASA Astrophysics Data System (ADS)

    Torres, Eduardo; Garcia-Sanz, Mario

    2004-04-01

    This article presents details of the new variable speed multipole large wind turbine TWT1650 designed by the M. Torres group and summarizes some experimental results of the control system. After several years of multidisciplinary research the first prototype TWT1650 began to work at Cabanillas Wind Farm (Spain) in August 2001. Since then a large number of operational data have been collected and used to improve the behaviour of the machine. The design and controller tuning have been accomplished using advanced QFT (quantitative feedback theory) robust control strategies and have been optimized based on analysis of that information. This article introduces the main advantages of the multipole system and shows and evaluates some of the most representative experimental results under extreme wind conditions. Copyright

  14. Immune Responses: Getting Close to Experimental Results with Cellular Automata Models

    NASA Astrophysics Data System (ADS)

    Dos Santos, Rita Maria Zorzenon

    Cellular automata approaches are powerful tools to model local and nonlocal interactions generating cooperative behavior. In the last decade, the question of whether cellular automata could embed realistic assumptions about the interactions among cells and molecules of the immune system was quite controversial. Recent results have shown that it is possible to use cellular automata approaches to describe realistically the interactions between the elements of the immune system. The first models using cellular automata approaches, boolean and threshold or window automata, were based on experimental evidence and were mainly used to understand the logic of global immune responses like immunization, tolerance, paralysis, etc. Recently, new classes of cellular automata models which include time delay, stochasticity or adaptation have lead to results that can be compared with in vivo experimental data.

  15. Experimental study on condensation heat transfer of steam on vertical titanium plates with different surface energies

    SciTech Connect

    Baojin, Qi; Li, Zhang; Hong, Xu; Yan, Sun

    2011-01-15

    Visual experiments were employed to investigate heat transfer characteristics of steam on vertical titanium plates with/without surface modifications for different surface energies. Stable dropwise condensation and filmwise condensation were achieved on two surface modification titanium plates, respectively. Dropwise and rivulet filmwise co-existing condensation form of steam was observed on unmodified titanium surfaces. With increase in the surface subcooling, the ratio of area ({eta}) covered by drops decreased and departure diameter of droplets increased, resulting in a decrease in condensation heat transfer coefficient. Condensation heat transfer coefficient decreased sharply with the values of {eta} decreasing when the fraction of the surface area covered by drops was greater than that covered by rivulets. Otherwise, the value of {eta} had little effect on the heat transfer performance. Based on the experimental phenomena observed, the heat flux through the surface was proposed to express as the sum of the heat flux through the dropwise region and rivulet filmwise region. The heat flux through the whole surface was the weighted mean value of the two regions mentioned above. The model presented explains the gradual change of heat transfer coefficient for transition condensation with the ratio of area covered by drops. The simulation results agreed well with the present experimental data when the subcooling temperature is lower than 10 C. (author)

  16. [Interactions of DNA bases with individual water molecules. Molecular mechanics and quantum mechanics computation results vs. experimental data].

    PubMed

    Gonzalez, E; Lino, J; Deriabina, A; Herrera, J N F; Poltev, V I

    2013-01-01

    To elucidate details of the DNA-water interactions we performed the calculations and systemaitic search for minima of interaction energy of the systems consisting of one of DNA bases and one or two water molecules. The results of calculations using two force fields of molecular mechanics (MM) and correlated ab initio method MP2/6-31G(d, p) of quantum mechanics (QM) have been compared with one another and with experimental data. The calculations demonstrated a qualitative agreement between geometry characteristics of the most of local energy minima obtained via different methods. The deepest minima revealed by MM and QM methods correspond to water molecule position between two neighbor hydrophilic centers of the base and to the formation by water molecule of hydrogen bonds with them. Nevertheless, the relative depth of some minima and peculiarities of mutual water-base positions in' these minima depend on the method used. The analysis revealed insignificance of some differences in the results of calculations performed via different methods and the importance of other ones for the description of DNA hydration. The calculations via MM methods enable us to reproduce quantitatively all the experimental data on the enthalpies of complex formation of single water molecule with the set of mono-, di-, and trimethylated bases, as well as on water molecule locations near base hydrophilic atoms in the crystals of DNA duplex fragments, while some of these data cannot be rationalized by QM calculations.

  17. A digital computer propulsion control facility: Description of capabilities and summary of experimental program results

    NASA Technical Reports Server (NTRS)

    Zeller, J. R.; Arpasi, D. J.; Lehtinen, B.

    1976-01-01

    Flight weight digital computers are being used today to carry out many of the propulsion system control functions previously delegated exclusively to hydromechanical controllers. An operational digital computer facility for propulsion control mode studies has been used successfully in several experimental programs. This paper describes the system and some of the results concerned with engine control, inlet control, and inlet engine integrated control. Analytical designs for the digital propulsion control modes include both classical and modern/optimal techniques.

  18. Kinematic Viscosities for Ether + Alkane Mixtures: Experimental Results and UNIFAC-VISCO Parameters

    NASA Astrophysics Data System (ADS)

    Bandrés, I.; Lahuerta, C.; Villares, A.; Martín, S.; Lafuente, Carlos

    2008-04-01

    Kinematic viscosities for the binary mixtures of diisopropylether, dibutylether or methyl ter-butyl ether with 3-methylpentane, hexane or heptane have been measured at 283.15 K, 298.15 K, and 313.15 K. The experimental values have been correlated by the McAllister equation. Using these results, new UNIFAC-VISCO parameters, Oether-CH2 and Oether-CH3, have been calculated.

  19. Columbus meteoroid/debris protection study - Experimental simulation techniques and results

    NASA Astrophysics Data System (ADS)

    Schneider, E.; Kitta, K.; Stilp, A.; Lambert, M.; Reimerdes, H. G.

    1992-08-01

    The methods and measurement techniques used in experimental simulations of micrometeoroid and space debris impacts with the ESA's laboratory module Columbus are described. Experiments were carried out at the two-stage light gas gun acceleration facilities of the Ernst-Mach Institute. Results are presented on simulations of normal impacts on bumper systems, oblique impacts on dual bumper systems, impacts into cooled targets, impacts into pressurized targets, and planar impacts of low-density projectiles.

  20. Numerical and experimental results on the spectral wave transfer in finite depth

    NASA Astrophysics Data System (ADS)

    Benassai, Guido

    2016-04-01

    Determination of the form of the one-dimensional surface gravity wave spectrum in water of finite depth is important for many scientific and engineering applications. Spectral parameters of deep water and intermediate depth waves serve as input data for the design of all coastal structures and for the description of many coastal processes. Moreover, the wave spectra are given as an input for the response and seakeeping calculations of high speed vessels in extreme sea conditions and for reliable calculations of the amount of energy to be extracted by wave energy converters (WEC). Available data on finite depth spectral form is generally extrapolated from parametric forms applicable in deep water (e.g., JONSWAP) [Hasselmann et al., 1973; Mitsuyasu et al., 1980; Kahma, 1981; Donelan et al., 1992; Zakharov, 2005). The present paper gives a contribution in this field through the validation of the offshore energy spectra transfer from given spectral forms through the measurement of inshore wave heights and spectra. The wave spectra on deep water were recorded offshore Ponza by the Wave Measurement Network (Piscopia et al.,2002). The field regressions between the spectral parameters, fp and the nondimensional energy with the fetch length were evaluated for fetch-limited sea conditions. These regressions gave the values of the spectral parameters for the site of interest. The offshore wave spectra were transfered from the measurement station offshore Ponza to a site located offshore the Gulf of Salerno. The offshore local wave spectra so obtained were transfered on the coastline with the TMA model (Bouws et al., 1985). Finally the numerical results, in terms of significant wave heights, were compared with the wave data recorded by a meteo-oceanographic station owned by Naples Hydrographic Office on the coastline of Salerno in 9m depth. Some considerations about the wave energy to be potentially extracted by Wave Energy Converters were done and the results were discussed.

  1. Experimental Investigation of A Heat Pipe-Assisted Latent Heat Thermal Energy Storage System

    NASA Astrophysics Data System (ADS)

    Tiari, Saeed; Mahdavi, Mahboobe; Qiu, Songgang

    2016-11-01

    In the present work, different operation modes of a latent heat thermal energy storage system assisted by a heat pipe network were studied experimentally. Rubitherm RT55 enclosed by a vertical cylindrical container was used as the Phase Change Material (PCM). The embedded heat pipe network consisting of a primary heat pipe and an array of four secondary heat pipes were employed to transfer heat to the PCM. The primary heat pipe transports heat from the heat source to the heat sink. The secondary heat pipes transfer the extra heat from the heat source to PCM during charging process or retrieve thermal energy from PCM during discharging process. The effects of heat transfer fluid (HTF) flow rate and temperature on the thermal performance of the system were investigated for both charging and discharging processes. It was found that the HTF flow rate has a significant effect on the total charging time of the system. Increasing the HTF flow rate results in a remarkable increase in the system input thermal power. The results also showed that the discharging process is hardly affected by the HTF flow rate but HTF temperature plays an important role in both charging and discharging processes. The authors would like to acknowledge the financial supports by Temple University for the project.

  2. Solution High-Energy Burst Assembly (SHEBA) results from subprompt critical experiments with uranyl fluoride fuel

    SciTech Connect

    Cappiello, C.C.; Butterfield, K.B.; Sanchez, R.G.

    1997-10-01

    The Solution High-Energy Burst Assembly (SHEBA) was originally constructed during 1980 and was designed to be a clean free-field geometry, right-circular, cylindrically symmetric critical assembly employing U(5%)O{sub 2}F{sub 2} solution as fuel. A second version of SHEBA, employing the same fuel but equipped with a fuel pump and shielding pit, was commissioned in 1993. This report includes data and operating experience for the 1993 SHEBA only. Solution-fueled benchmark work focused on the development of experimental measurements of the characterization of SHEBA; a summary of the results are given. A description of the system and the experimental results are given in some detail in the report. Experiments were designed to: (1) study the behavior of nuclear excursions in a low-enrichment solution, (2) evaluate accidental criticality alarm detectors for fuel-processing facilities, (3) provide radiation spectra and dose measurements to benchmark radiation transport calculations on a low-enrichment solution system similar to centrifuge enrichment plants, and (4) provide radiation fields to calibrate personnel dosimetry. 15 refs., 37 figs., 10 tabs.

  3. Experimental results of a new system using microwaves for vision correction

    NASA Astrophysics Data System (ADS)

    Ryan, Thomas P.; Pertaub, Radha; Meyers, Steven R.; Dresher, Russell P.; Scharf, Ronald

    2009-02-01

    Technology is in development to correct vision without the use of lasers or cutting of the eye. Many current technologies used to reshape the cornea are invasive, in that either RF needles are placed into the cornea or a flap is cut and then a laser used to ablate the cornea in the optical zone. Keraflex, a therapeutic microwave treatment, is a noninvasive, non-incisional refractive surgery procedure capable of treating myopia (nearsightedness). The goal is to create a predictable refractive change in the optical zone, while preserving the epithelium and deeper structures of the eye. A further goal is to avoid incisions and damage to the epithelium which both require a post-treatment healing period. Experimental work with fresh porcine eyes examined the following variables: duration of the RF pulse, RF power level, coolant amount and timing, electrode spacing, applanation force against the eye, initial eye temperature, and age of eye. We measured curvature changes of the eye with topography, Scheimpflug, Wavefront aberrometry or other means to characterize diopter change as an important endpoint. Other assessment includes evaluation of a fine white ring seen in the cornea following treatment. Dose studies have been done to correlate the treated region with energy delivered. The timing and dosing of energy and cooling were investigated to achieve the target diopter change in vision.

  4. Comment on ``Experimental Free Energy Reconstruction From Single-Molecule Force Spectroscopy Using Jarzynski's Equality''

    SciTech Connect

    Friddle, R W

    2008-01-14

    Harris, Song and Kiang [1] (HSK) describe their results on reconstructing the free energy profiles for both the stretch of the titin polymer, and the unfolding of an individual I27 domain. The new finding reported in [1] is the measurement of the free energy barrier (or activation energy) to unfolding the I27 domain. Due to a misinterpretation of the mechanics involved, the free energy surface (and thus the energy barrier) to unfolding the I27 domain was not measured.

  5. Research supported by the department of energy Task C: Experimental high energy physics. 1995 Final report

    SciTech Connect

    Brau, J.

    1996-07-01

    This report describes work of the University of Oregon high-energy physics group related to the Stanford Linear Detector, LEP`s OPAL detector, the NuTeV experiment at Fermilab, the SSC`s GEM detector, and top-quark studies at the Next Linear Collider. 160 refs., 53 figs., 12 tabs.

  6. Experimental and theoretical triple differential cross sections for electron-impact ionization of Ar (3p) for equal energy final state electrons

    NASA Astrophysics Data System (ADS)

    Amami, Sadek; Ozer, Zehra N.; Dogan, Mevlut; Yavuz, Murat; Varol, Onur; Madison, Don

    2016-09-01

    There have been several studies of electron-impact ionization of inert gases for asymmetric final state energy sharing and normally one electron has an energy significantly higher than the other. However, there have been relatively few studies examining equal energy final state electrons. Here we report experimental and theoretical triple differential cross sections for electron impact ionization of Ar (3p) for equal energy sharing of the outgoing electrons. Previous experimental results combined with some new measurements are compared with distorted wave born approximation (DWBA) results, DWBA results using the Ward-Macek (WM) approximation for the post collision interaction (PCI), and three-body distorted wave (3DW) which includes PCI without approximation. The results show that it is crucially important to include PCI in the calculation particularly for lower energies and that the WM approximation is valid only for high energies. The 3DW, on the other hand, is in reasonably good agreement with data down to fairly low energies.

  7. Respiratory rate detection algorithm based on RGB-D camera: theoretical background and experimental results.

    PubMed

    Benetazzo, Flavia; Freddi, Alessandro; Monteriù, Andrea; Longhi, Sauro

    2014-09-01

    Both the theoretical background and the experimental results of an algorithm developed to perform human respiratory rate measurements without any physical contact are presented. Based on depth image sensing techniques, the respiratory rate is derived by measuring morphological changes of the chest wall. The algorithm identifies the human chest, computes its distance from the camera and compares this value with the instantaneous distance, discerning if it is due to the respiratory act or due to a limited movement of the person being monitored. To experimentally validate the proposed algorithm, the respiratory rate measurements coming from a spirometer were taken as a benchmark and compared with those estimated by the algorithm. Five tests were performed, with five different persons sat in front of the camera. The first test aimed to choose the suitable sampling frequency. The second test was conducted to compare the performances of the proposed system with respect to the gold standard in ideal conditions of light, orientation and clothing. The third, fourth and fifth tests evaluated the algorithm performances under different operating conditions. The experimental results showed that the system can correctly measure the respiratory rate, and it is a viable alternative to monitor the respiratory activity of a person without using invasive sensors.

  8. Respiratory rate detection algorithm based on RGB-D camera: theoretical background and experimental results

    PubMed Central

    Freddi, Alessandro; Monteriù, Andrea; Longhi, Sauro

    2014-01-01

    Both the theoretical background and the experimental results of an algorithm developed to perform human respiratory rate measurements without any physical contact are presented. Based on depth image sensing techniques, the respiratory rate is derived by measuring morphological changes of the chest wall. The algorithm identifies the human chest, computes its distance from the camera and compares this value with the instantaneous distance, discerning if it is due to the respiratory act or due to a limited movement of the person being monitored. To experimentally validate the proposed algorithm, the respiratory rate measurements coming from a spirometer were taken as a benchmark and compared with those estimated by the algorithm. Five tests were performed, with five different persons sat in front of the camera. The first test aimed to choose the suitable sampling frequency. The second test was conducted to compare the performances of the proposed system with respect to the gold standard in ideal conditions of light, orientation and clothing. The third, fourth and fifth tests evaluated the algorithm performances under different operating conditions. The experimental results showed that the system can correctly measure the respiratory rate, and it is a viable alternative to monitor the respiratory activity of a person without using invasive sensors. PMID:26609383

  9. Wind Code Application to External Forebody Flowfields with Comparisons to Experimental Results

    NASA Technical Reports Server (NTRS)

    Frate, F. C.; Kim, H. D.

    2001-01-01

    The WIND Code, a general purpose Navier-Stokes solver, has been utilized to obtain supersonic external flowfield Computational Fluid Dynamics (CFD) solutions over an axisymmetric, parabolic forebody with comparisons made to wind tunnel experimental results. Various cases have been investigated at supersonic freestream conditions ranging from Mach 2.0 to 3.5, at 0 deg and 3 deg angles-of-attack, and with either a sharp-nose or blunt-nose forebody configuration. Both a turbulent (Baldwin-Lomax algebraic turbulence model) and a laminar model have been implemented in the CFD. Obtaining the solutions involved utilizing either the parabolized- or full-Navier-Stokes analyses supplied in WIND. Comparisons have been made with static pressure measurements, with boundary-layer rake and flowfield rake pitot pressure measurements, and with temperature sensitive paint experimental results. Using WIND's parabolized Navier-Stokes capability, grid sequencing, and the Baldwin-Lomax algebraic turbulence model allowed for significant reductions in computational time while still providing good agreement with experiment. Given that CFD and experiment compare well, WIND is found to be a good computational platform for solving this type of forebody problem, and the grids developed in conjunction with it will be used in the future to investigate varying freestream conditions not tested experimentally.

  10. Experimental laser anastomosis of the large bowel: conclusive results and future prospect

    NASA Astrophysics Data System (ADS)

    Kawahara, Masaki; Kuramoto, Shu; Ryan, Peter

    2003-06-01

    Completely sutureless end-to-end large bowel anastomoses were successfully performed in New Zealand white rabbits by using 1064 nm, 0.4-W power pulsating Nd:YAG laser to produce welding. Purpose: The aim of this study was to assess the results of our whole experimental data and summarize our experimental work on laser colon anastomosis. Methods: This experimental study investigated integrity of anastomosis, degree of narrowing, macroscopic appearance, microscopic findings, animal body weight change, and collagen concentration of laser colon anastomoses, compared with those of conventional sutured anastomoses up to ninety postoperative days. Results: Bursting pressures of laser anastomoses were at first low and came to be equivalent at seven days, but the laser group exhibited a consistent narrowing tendency. However, laser anastomoses demonstrated fewer and milder adhesions, and animals showed a better recovery of body weight. Histologically, laser anastomoses showed better layer-to-layer reconstitution without foreign body response and with less fibrosis. Difference in collagen concentration did not reach statistical significance. Conclusion: The technique of laser anastomosis presents a promising alternative to suturing in reconstitution of the large bowel.

  11. Electromagnetic Vortex-Based Radar Imaging Using a Single Receiving Antenna: Theory and Experimental Results

    PubMed Central

    Yuan, Tiezhu; Wang, Hongqiang; Cheng, Yongqiang; Qin, Yuliang

    2017-01-01

    Radar imaging based on electromagnetic vortex can achieve azimuth resolution without relative motion. The present paper investigates this imaging technique with the use of a single receiving antenna through theoretical analysis and experimental results. Compared with the use of multiple receiving antennas, the echoes from a single receiver cannot be used directly for image reconstruction using Fourier method. The reason is revealed by using the point spread function. An additional phase is compensated for each mode before imaging process based on the array parameters and the elevation of the targets. A proof-of-concept imaging system based on a circular phased array is created, and imaging experiments of corner-reflector targets are performed in an anechoic chamber. The azimuthal image is reconstructed by the use of Fourier transform and spectral estimation methods. The azimuth resolution of the two methods is analyzed and compared through experimental data. The experimental results verify the principle of azimuth resolution and the proposed phase compensation method. PMID:28335487

  12. Some experimental results on Coanda effect with application to a flying vehicle

    NASA Astrophysics Data System (ADS)

    Crivoi, O.; Doroftei, I.

    2016-08-01

    In this paper some experimental results related to the Coanda effect are presented. The idea is to use them to build and control a flying vehicle. Our experiments have been done on an laboratory testing device. From the first obtained results we have seen some advantages and disadvantages to applying Coanda effect to a flying vehicle. The advantages are: reducing the pressure near the of the convex surface, protected screw, vertical takeoff and landing. The main disadvantage is the cost of the fuselage and the extra weight that he has. Our conclusion at this time is that this technical solution can bring some benefits through a suited sizing and geometry with vehicle mass.

  13. Studies of Multipactor in Dielectric-Loaded Accelerator Structures: Comparison of Simulation Results with Experimental Data

    SciTech Connect

    Sinitsyn, Oleksandr; Nusinovich, Gregory; Antonsen, Thomas Jr.

    2010-11-04

    In this paper new results of numerical studies of multipactor in dielectric-loaded accelerator structures are presented. The results are compared with experimental data obtained during recent studies of such structures performed by Argonne National Laboratory, the Naval Research Laboratory, SLAC National Accelerator Laboratory and Euclid TechLabs, LLC. Good agreement between the theory and experiment was observed for the structures with larger inner diameter, however the structures with smaller inner diameter demonstrated a discrepancy between the two. Possible reasons for such discrepancy are discussed.

  14. Shuttle Return To Flight Experimental Results: Cavity Effects on Boundary Layer Transition

    NASA Technical Reports Server (NTRS)

    Liechty, Derek S.; Horvath, Thomas J.; Berry, Scott A.

    2006-01-01

    The effect of an isolated rectangular cavity on hypersonic boundary layer transition of the windward surface of the Shuttle Orbiter has been experimentally examined in the Langley Aerothermodynamics Laboratory in support of an agency-wide effort to prepare the Shuttle Orbiter for return to flight. This experimental study was initiated to provide a cavity effects database for developing hypersonic transition criteria to support on-orbit decisions to repair a damaged thermal protection system. Boundary layer transition results were obtained using 0.0075-scale Orbiter models with simulated tile damage (rectangular cavities) of varying length, width, and depth. The database contained within this report will be used to formulate cavity-induced transition correlations using predicted boundary layer edge parameters.

  15. LBE water interaction in sub-critical reactors: First experimental and modelling results

    NASA Astrophysics Data System (ADS)

    Ciampichetti, A.; Agostini, P.; Benamati, G.; Bandini, G.; Pellini, D.; Forgione, N.; Oriolo, F.; Ambrosini, W.

    2008-06-01

    This paper concerns the study of the phenomena involved in the interaction between LBE and pressurised water which could occur in some hypothetical accidents in accelerator driven system type reactors. The LIFUS 5 facility was designed and built at ENEA-Brasimone to reproduce this kind of interaction in a wide range of conditions. The first test of the experimental program was carried out injecting water at 70 bar and 235 °C in a reaction vessel containing LBE at 1 bar and 350 °C. A pressurisation up to 80 bar was observed in the test section during the considered transient. The SIMMER III code was used to simulate the performed test. The calculated data agree in a satisfactory way with the experimental results giving confidence in the possibility to use this code for safety analyses of heavy liquid metal cooled reactors.

  16. Acoustic time delay estimation and sensor network self-localization: Experimental results

    NASA Astrophysics Data System (ADS)

    Ash, Joshua N.; Moses, Randolph L.

    2005-08-01

    Experimental results are presented on propagation, coherence, and time-delay estimation (TDE) from a microphone array in an outdoor aeroacoustic environment. The primary goal is to understand the achievable accuracy of acoustic TDE using low-cost, commercial off-the-shelf (COTS) speakers and microphones. In addition, through the use of modulated pseudo-noise sequences, the experiment seeks to provide an empirical understanding of the effects of center frequency, bandwidth, and signal duration on TDE effectiveness and compares this to the theoretical expectations established by the Weiss-Weinstein lower bound. Finally, sensor network self-localization is performed using a maximum likelihood estimator and the time-delay estimates. Experimental network localization error is presented as a function of the acoustic calibration signal parameters.

  17. Supersonic Retropropulsion Experimental Results from the NASA Ames 9- x 7-Foot Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Berry, Scott A.; Rhode, Matthew N.; Edquist, Karl T.

    2012-01-01

    Supersonic retropropulsion was experimentally examined in the Ames Research Center 9x7-Foot Supersonic Wind Tunnel at Mach 1.8 and 2.4. The experimental model, previously designed for and tested in the Langley Research Center Unitary Plan Wind Tunnel at Mach 2.4, 3.5 and 4.6, was a 5-in diameter 70-deg sphere-cone forebody with a 9.55-in long cylindrical aftbody. The forebody was designed to accommodate up to four 4:1 area ratio nozzles, one on the model centerline and the other three on the half radius spaced 120-deg apart. Surface pressure and flow visualization were the primary measurements, including high-speed data to investigate the dynamics of the interactions between the bow and nozzle shocks. Three blowing configurations were tested with thrust coefficients up to 10 and angles of attack up to 20-deg. Preliminary results and observations from the test are provided

  18. Circular Samples as Objects for Magnetic Resonance Imaging - Mathematical Simulation, Experimental Results

    NASA Astrophysics Data System (ADS)

    Frollo, Ivan; Krafčík, Andrej; Andris, Peter; Přibil, Jiří; Dermek, Tomáš

    2015-12-01

    Circular samples are the frequent objects of "in-vitro" investigation using imaging method based on magnetic resonance principles. The goal of our investigation is imaging of thin planar layers without using the slide selection procedure, thus only 2D imaging or imaging of selected layers of samples in circular vessels, eppendorf tubes,.. compulsorily using procedure "slide selection". In spite of that the standard imaging methods was used, some specificity arise when mathematical modeling of these procedure is introduced. In the paper several mathematical models were presented that were compared with real experimental results. Circular magnetic samples were placed into the homogenous magnetic field of a low field imager based on nuclear magnetic resonance. For experimental verification an MRI 0.178 Tesla ESAOTE Opera imager was used.

  19. Shuttle Return To Flight Experimental Results: Protuberance Effects on Boundary Layer Transition

    NASA Technical Reports Server (NTRS)

    Liechty, Derek S.; Berry, Scott A.; Horvath, Thomas J.

    2006-01-01

    The effect of isolated roughness elements on the windward boundary layer of the Shuttle Orbiter has been experimentally examined in the Langley Aerothermodynamic Laboratory in support of an agency-wide effort to prepare the Shuttle Orbiter for return to flight. This experimental effort was initiated to provide a roughness effects database for developing transition criteria to support on-orbit decisions to repair damage to the thermal protection system. Boundary layer transition results were obtained using trips of varying heights and locations along the centerline and attachment lines of 0.0075-scale models. Global heat transfer images using phosphor thermography of the Orbiter windward surface and the corresponding heating distributions were used to infer the state of the boundary layer (laminar, transitional, or turbulent). The database contained within this report will be used to formulate protuberance-induced transition correlations using predicted boundary layer edge parameters.

  20. First experimental results from DC/DC and AC/DC plasma-based power transformers

    NASA Astrophysics Data System (ADS)

    McEvoy, Aaron; Gibson, William; Nebel, Richard

    2016-10-01

    A plasma-based power transformer has been built and operated in both DC/DC and AC/DC mode. The proprietary Tibbar Plasma Technologies, Inc. transformer design consists of two cylindrically symmetric helical primary electrodes surrounding a low temperature plasma within which a secondary axial current is generated. Initial experimental results have compared well with simulations and moderate conversion efficiencies have been observed. A new proprietary device is currently being constructed that will utilize 3-phase 480 VAC input to achieve higher conversion efficiency and output power. A description of the apparatus and several potential applications will be presented along with preliminary experimental data demonstrating the DC/DC and AC/DC conversion processes. Work performed under ARPA-E contract DE-AR0000677.

  1. Artificial cochlea and acoustic black hole travelling waves observation: Model and experimental results

    NASA Astrophysics Data System (ADS)

    Foucaud, Simon; Michon, Guilhem; Gourinat, Yves; Pelat, Adrien; Gautier, François

    2014-07-01

    An inhomogeneous fluid structure waveguide reproducing passive behaviour of the inner ear is modelled with the help of the Wentzel-Kramers-Brillouin method. A physical setup is designed and built. Experimental results are compared with a good correlation to theoretical ones. The experimental setup is a varying width plate immersed in fluid and terminated with an acoustic black hole. The varying width plate provides a spatial repartition of the vibration depending on the excitation frequency. The acoustic black hole is made by decreasing the plate's thickness with a quadratic profile and by covering this region with a thin film of viscoelastic material. Such a termination attenuates the flexural wave reflection at the end of the waveguide, turning standing waves into travelling waves.

  2. Stimulating Contributions to Public Goods through Information Feedback: Some Experimental Results

    PubMed Central

    Janssen, Marco A.; Lee, Allen; Sundaram, Hari

    2016-01-01

    In traditional public good experiments participants receive an endowment from the experimenter that can be invested in a public good or kept in a private account. In this paper we present an experimental environment where participants can invest time during five days to contribute to a public good. Participants can make contributions to a linear public good by logging into a web application and performing virtual actions. We compared four treatments, with different group sizes and information of (relative) performance of other groups. We find that information feedback about performance of other groups has a small positive effect if we control for various attributes of the groups. Moreover, we find a significant effect of the contributions of others in the group in the previous day on the number of points earned in the current day. Our results confirm that people participate more when participants in their group participate more, and are influenced by information about the relative performance of other groups. PMID:27459070

  3. Design and Experimental Results for the S825 Airfoil; Period of Performance: 1998-1999

    SciTech Connect

    Somers, D. M.

    2005-01-01

    A 17%-thick, natural-laminar-flow airfoil, the S825, for the 75% blade radial station of 20- to 40-meter, variable-speed and variable-pitch (toward feather), horizontal-axis wind turbines has been designed and analyzed theoretically and verified experimentally in the NASA Langley Low-Turbulence Pressure Tunnel. The two primary objectives of high maximum lift, relatively insensitive to roughness and low-profile drag have been achieved. The airfoil exhibits a rapid, trailing-edge stall, which does not meet the design goal of a docile stall. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results generally show good agreement.

  4. Vibration Based Crack Detection in a Rotating Disk. Part 2; Experimental Results

    NASA Technical Reports Server (NTRS)

    Gyekenyesi, Andrew L.; Sawicki, Jerzy T.; Martin, Richard E.; Haase, Wayne C.; Baaklini, George

    2005-01-01

    This paper describes the experimental results concerning the detection of a crack in a rotating disk. The goal was to utilize blade tip clearance and shaft vibration measurements to monitor changes in the system's center of mass and/or blade deformation behaviors. The concept of the approach is based on the fact that the development of a disk crack results in a distorted strain field within the component. As a result, a minute deformation in the disk's geometry as well as a change in the system's center of mass occurs. Here, a notch was used to simulate an actual crack. The vibration based experimental results failed to identify the existence of a notch when utilizing the approach described above, even with a rather large, circumferential notch (l.2 in.) located approximately mid-span on the disk (disk radius = 4.63 in. with notch at r = 2.12 in.). This was somewhat expected, since the finite element based results in Part 1 of this study predicted changes in blade tip clearance as well as center of mass shifts due to a notch to be less than 0.001 in. Therefore, the small changes incurred by the notch could not be differentiated from the mechanical and electrical noise of the rotor system. Although the crack detection technique of interest failed to identify the existence ofthe notch, the vibration data produced and captured here will be utilized in upcoming studies that will focus on different data mining techniques concerning damage detection in a disk.

  5. Laboratory simulations of lidar returns from clouds - Experimental and numerical results

    NASA Astrophysics Data System (ADS)

    Zaccanti, Giovanni; Bruscaglioni, Piero; Gurioli, Massimo; Sansoni, Paola

    1993-03-01

    The experimental results of laboratory simulations of lidar returns from clouds are presented. Measurements were carried out on laboratory-scaled cloud models by using a picosecond laser and a streak-camera system. The turbid structures simulating clouds were suspensions of polystyrene spheres in water. The geometrical situation was similar to that of an actual lidar sounding a cloud 1000 m distant and with a thickness of 300 m. Measurements were repeated for different concentrations and different sizes of spheres. The results show how the effect of multiple scattering depends on the scattering coefficient and on the phase function of the diffusers. The depolarization introduced by multiple scattering was also investigated. The results were also compared with numerical results obtained by Monte Carlo simulations. Substantially good agreement between numerical and experimental results was found. The measurements showed the adequacy of modern electro-optical systems to study the features of multiple-scattering effects on lidar echoes from atmosphere or ocean by means of experiments on well-controlled laboratory-scaled models. This adequacy provides the possibility of studying the influence of different effects in the laboratory in well-controlled situations.

  6. Laboratory simulations of lidar returns from clouds: experimental and numerical results.

    PubMed

    Zaccanti, G; Bruscaglioni, P; Gurioli, M; Sansoni, P

    1993-03-20

    The experimental results of laboratory simulations of lidar returns from clouds are presented. Measurements were carried out on laboratory-scaled cloud models by using a picosecond laser and a streak-camera system. The turbid structures simulating clouds were suspensions of polystyrene spheres in water. The geometrical situation was similar to that of an actual lidar sounding a cloud 1000 m distant and with a thickness of 300 m. Measurements were repeated for different concentrations and different sizes of spheres. The results show how the effect of multiple scattering depends on the scattering coefficient and on the phase function of the diffusers. The depolarization introduced by multiple scattering was also investigated. The results were also compared with numerical results obtained by Monte Carlo simulations. Substantially good agreement between numerical and experimental results was found. The measurements showed the adequacy of modern electro-optical systems to study the features of multiple-scattering effects on lidar echoes from atmosphere or ocean by means of experiments on well-controlled laboratory-scaled models. This adequacy provides the possibility of studying the influence of different effects in the laboratory in well-controlled situations.

  7. Experimental verification of a bridge-shaped, nonlinear vibration energy harvester

    SciTech Connect

    Gafforelli, Giacomo Corigliano, Alberto; Xu, Ruize; Kim, Sang-Gook

    2014-11-17

    This paper reports a comprehensive modeling and experimental characterization of a bridge shaped nonlinear energy harvester. A doubly clamped beam at large deflection requires stretching strain in addition to the bending strain to be geometrically compatible, which stiffens the beam as the beam deflects and transforms the dynamics to a nonlinear regime. The Duffing mode non-linear resonance widens the frequency bandwidth significantly at higher frequencies than the linear resonant frequency. The modeling includes a nonlinear measure of strain coupled with piezoelectric constitutive equations which end up in nonlinear coupling terms in the equations of motion. The main result supports that the power generation is bounded by the mechanical damping for both linear and nonlinear harvesters. Modeling also shows the power generation is over a wider bandwidth in the nonlinear case. A prototype is manufactured and tested to measure the power generation at different load resistances and acceleration amplitudes. The prototype shows a nonlinear behavior with well-matched experimental data to the modeling.

  8. Experimental determination of in situ utilization of lunar regolith for thermal energy storage

    NASA Astrophysics Data System (ADS)

    Richter, Scott W.

    1993-01-01

    A Lunar Thermal Energy from Regolith (LUTHER) experiment has been designed and fabricated at the NASA Lewis Research Center to determine the feasibility of using lunar soil as thermal energy storage media. The experimental apparatus includes an alumina ceramic canister (25.4 cm diameter by 45.7 cm length) which contains simulated lunar regolith, a heater (either radiative or conductive), 9 heat shields, a heat transfer cold jacket, and 19 type B platinum rhodium thermocouples. The simulated lunar regolith is a basalt, mined and processed by the University of Minnesota, that closely resembles the lunar basalt returned to earth by the Apollo missions. The experiment will test the effects of vacuum, particle size, and density on the thermophysical properties of the regolith. The properties include melt temperature (range), specific heat, thermal conductivity, and latent heat of storage. Two separate tests, using two different heaters, will be performed to study the effect of heating the system using radiative and conductive heat transfer. The physical characteristics of the melt pattern, material compatibility of the molten regolith, and the volatile gas emission will be investigated by heating a portion of the lunar regolith to its melting temperature (1435 K) in a 10(exp -4) pascal vacuum chamber, equipped with a gas spectrum analyzer. A finite differencing SINDA model was developed at NASA Lewis Research Center to predict the performance of the LUTHER experiment. The analytical results of the code will be compared with the experimental data generated by the LUTHER experiment. The code will predict the effects of vacuum, particle size, and density has on the heat transfer to the simulated regolith.

  9. Experimental Determination of in Situ Utilization of Lunar Regolith for Thermal Energy Storage

    NASA Technical Reports Server (NTRS)

    Richter, Scott W.

    1993-01-01

    A Lunar Thermal Energy from Regolith (LUTHER) experiment has been designed and fabricated at the NASA Lewis Research Center to determine the feasibility of using lunar soil as thermal energy storage media. The experimental apparatus includes an alumina ceramic canister (25.4 cm diameter by 45.7 cm length) which contains simulated lunar regolith, a heater (either radiative or conductive), 9 heat shields, a heat transfer cold jacket, and 19 type B platinum rhodium thermocouples. The simulated lunar regolith is a basalt, mined and processed by the University of Minnesota, that closely resembles the lunar basalt returned to earth by the Apollo missions. The experiment will test the effects of vacuum, particle size, and density on the thermophysical properties of the regolith. The properties include melt temperature (range), specific heat, thermal conductivity, and latent heat of storage. Two separate tests, using two different heaters, will be performed to study the effect of heating the system using radiative and conductive heat transfer. The physical characteristics of the melt pattern, material compatibility of the molten regolith, and the volatile gas emission will be investigated by heating a portion of the lunar regolith to its melting temperature (1435 K) in a 10(exp -4) pascal vacuum chamber, equipped with a gas spectrum analyzer. A finite differencing SINDA model was developed at NASA Lewis Research Center to predict the performance of the LUTHER experiment. The analytical results of the code will be compared with the experimental data generated by the LUTHER experiment. The code will predict the effects of vacuum, particle size, and density has on the heat transfer to the simulated regolith.

  10. Electroelastic modeling and experimental validations of piezoelectric energy harvesting from broadband random vibrations of cantilevered bimorphs

    NASA Astrophysics Data System (ADS)

    Zhao, S.; Erturk, A.

    2013-01-01

    We present electroelastic modeling, analytical and numerical solutions, and experimental validations of piezoelectric energy harvesting from broadband random vibrations. The modeling approach employed herein is based on a distributed-parameter electroelastic formulation to ensure that the effects of higher vibration modes are included, since broadband random vibrations, such as Gaussian white noise, might excite higher vibration modes. The goal is to predict the expected value of the power output and the mean-square shunted vibration response in terms of the given power spectral density (PSD) or time history of the random vibrational input. The analytical method is based on the PSD of random base excitation and distributed-parameter frequency response functions of the coupled voltage output and shunted vibration response. The first of the two numerical solution methods employs the Fourier series representation of the base acceleration history in an ordinary differential equation solver while the second method uses an Euler-Maruyama scheme to directly solve the resulting electroelastic stochastic differential equations. The analytical and numerical simulations are compared with several experiments for a brass-reinforced PZT-5H bimorph under different random excitation levels. The simulations exhibit very good agreement with the experimental measurements for a range of resistive electrical boundary conditions and input PSD levels. It is also shown that lightly damped higher vibration modes can alter the expected power curve under broadband random excitation. Therefore, the distributed-parameter modeling and solutions presented herein can be used as a more accurate alternative to the existing single-degree-of-freedom solutions for broadband random vibration energy harvesting.

  11. Results of design studies and wind tunnel tests of an advanced high lift system for an Energy Efficient Transport

    NASA Technical Reports Server (NTRS)

    Oliver, W. R.

    1980-01-01

    The development of an advanced technology high lift system for an energy efficient transport incorporating a high aspect ratio supercritical wing is described. This development is based on the results of trade studies to select the high lift system, analysis techniques utilized to design the high lift system, and results of a wind tunnel test program. The program included the first experimental low speed, high Reynolds number wind tunnel test for this class of aircraft. The experimental results include the effects on low speed aerodynamic characteristics of various leading and trailing edge devices, nacelles and pylons, aileron, spoilers, and Mach and Reynolds numbers. Results are discussed and compared with the experimental data and the various aerodynamic characteristics are estimated.

  12. Free space optical communication flight mission: simulations and experimental results on ground level demonstrator

    NASA Astrophysics Data System (ADS)

    Mata Calvo, Ramon; Ferrero, Valter; Camatel, Stefano; Catalano, Valeria; Bonino, Luciana; Toselli, Italo

    2009-05-01

    In the context of the increasing demand in high-speed data link for scientific, planetary exploration and earth observation missions, the Italian Space Agency (ASI), involving Thales Alenia Space as prime, the Polytechnic of Turin and other Italian partners, is developing a program for feasibility demonstration of optical communication system with the goal of a prototype flight mission in the next future. We have designed and analyzed a ground level bidirectional Free Space Optical Communication (FSOC) Breadboard at 2.5Gbit/s working at 1550nm as an emulator of slant path link. The breadboard is full-working and we tested it back-toback, at 500m and 2.3km during one month. The distances were chosen in order to get an equivalent slant path cumulative turbulence in a ground level link. The measurements campaign was done during the day and the night time and under several weather conditions, from sunny, rainy or windy. So we could work under very different turbulence conditions from weak to strong turbulence. We measured the scintillation both, on-axis and off-axis by introducing known misalignments at the terminals, transmission losses at both path lengths and BER at both receivers. We present simulations results considering slant and ground level links, where we took into account the atmospheric effects; scintillation, beam spread, beam wander and fade probability, and comparing them with the ground level experimental results, we find a good agreement between them. Finally we discuss the results obtained in the experimentation and in the flight mission simulations in order to apply our experimental results in the next project phases.

  13. Universe Clinopyroxene barometer -recalibrations on the results of the orthopyroxene thermobarometry and experimental results and applications to the clinopyroxene geotherms

    NASA Astrophysics Data System (ADS)

    Ashchepkov, I. V.

    2009-04-01

    The internal exchange of Jd-Di components on clinopyroxene allow to calibrate the universal clinopyroxene thermobarometer (Ashchepkov, 2001; 2002; 2003) based on experimental data for different systems including peridotitic, eclogitic and igneous which are represented by the augite cumulates as well as salites from the basic granulates from low crust. The equation to the peridotitic system was calibrated on the results of the othopyroxene thermobarometry (Brey. Kohler,1990- McGregor,1974). Modifications allow receiving the better agreement with the orthopyroxene estimates and results of polymineral thermobarometry (Brey, Kohler, 1990) as well as the clinopyroxene thermobarometry (Nimis, Taylor, 2000). The following equation allows working with the peridotite of the mantle lithosphere beneath cratons (30-80) kbar. P(Ash2009)=0.32 (1-0.2*Na/Al+0.012*Fe/Na)*Kd^(3/4)*ToK/(1+Fe)-35*ln(1273/ToK)*(Al+Ti+2.5Na+1.5Fe3+)+(0.9-CaO)*10+Na20/Al2O3*ToK /200 with the second iteration P=(0.0000002* P4 +0.000002+P^3-0.0027*P^2+1.2241*P) Checking of the HP experiments (Brey et al 2008, Walter, 1998; Falloon, Green, 1989; Dasgupta et al., 2007 etc.) it show the precision close to those of the best barometers (McGregor, 1974) ~5-7 but much more wider compositional range including metasomatic associations and The equation for the Al - rich assemblages allow to obtain the pressure estimates fro the megacrystalls and Al - rich peridotitic clinopyroxenes from the mantle xenoliths carried by alkaline basalts: P(Ash2009)=0.035*Kd*ToK(1+2.44Fe)-50.2 ln(1273/ToK) (Al+Ti+Na) Together with the clinopyroxene thermometer (Nimis, Taylor, 2000) it produces the TP estimates very close to those obtained with (Brey, Kohler, 1990) and values of experiments for the melting of basalts. The meagacrystalls show the polybaric origin and their range of estimated pressure corresponds well to determined for mantle peridotites and pyroxenites. The clinopyroxene geotherms for S. Africa (Boyd, Nixon, 1974

  14. Vibrationally inelastic collisions of H+D2: a comparison of quantum mechanical, quasiclassical, and experimental results.

    PubMed

    Jambrina, P G; Aldegunde, J; Castillo, J F; Aoiz, F J; Sáez Rábanos, V

    2009-01-21

    A detailed comparison of quantum mechanical (QM) and quasiclassical trajectory (QCT) integral and differential cross sections (DCSs) as well as opacity functions is presented in this work for the vibrationally inelastic collisions of H+D(2)(v=0,j=0)-->H+D(2)(v(')=3,j(')) at 1.72 eV collision energy. These results are also compared with the experimental differential cross sections by Greaves et al. [Nature (London) 454, 88 (2008)]. The agreement between QCT and QM results is fairly good but some differences are appreciable, and it is shown that the experimental results are in a somewhat better agreement with the calculated QM DCS. The present results and their analysis confirm that the vibrational excitation takes place by elongation of the D-D bond in a "tug-of-war" mechanism, where the incoming H atom and one of the D atoms compete for the formation of a bond with the other D atom, as proposed by Greaves et al. It is also found that these collisions may give rise to the formation of short-lived collision complexes (tau(coll)=35-50 fs) that can be traced back to the presence of relatively deep wells in the potential surface when the original D-D bond is stretched. The analysis of the trajectories into v(')=3 reveals that most of them cross at least twice the reaction barrier via a recrossing mechanism.

  15. Experimental study on load characteristics in a floating type pendulum wave energy converter

    NASA Astrophysics Data System (ADS)

    Murakami, Tengen; Imai, Yasutaka; Nagata, Shuichi

    2014-10-01

    A floating type pendulum wave energy converter (FPWEC) with a rotary vane pump as the power take-off system was proposed by Watabe et al. in 1998. They showed that this device had high energy conversion efficiency. In the previous research, the authors conducted 2D wave tank tests in regular waves to evaluate the generating efficiency of FPWEC with a power take-off system composed of pulleys, belts and a generator. As a result, the influence of the electrical load on the generating efficiency was shown. Continuously, the load characteristics of FPWEC are pursued experimentally by using the servo motors to change the damping coefficient in this paper. In a later part of this paper, the motions of the model with the servo motors are compared with that of the case with the same power take-off system as the previous research. From the above experiment, it may be concluded that the maximum primary conversion efficiency is achieved as high as 98% at the optimal load.

  16. Experimental and theoretical high energy physics. Progress report 1 Oct 1979 to 30 Sep 1980

    SciTech Connect

    Gasiorowicz, S.; Fishbane, P.; Kaus, P.; Riverside, U. C.; Geffen, D. A.; Wilson, W.; Suura, Hiroshi; Haqq, Emmanuel; Rosner, Jonathan L.; Kwong, Waikwok; Schonfeld, Jonathan F.; Quigg, C.; Thacker, H. B.; Moxhay, Peter; Robinett, Richard; Karl, Gabriel; Meshkov, Sydney

    1980-09-30

    Research performed in theoretical high energy physics includes: nonabelian Stokes theorem; connection between asymptotic behavior and bound states in QCD; classical solutions for gauge fields interacting with Higgs mesons; neutrino oscillations; relativistic wave equation and mass spectrum of gluonium; dynamical structures of the pion; convergence of reflectionless approximations to confining potentials; degeneracy in one-dimensional quantum mechanics; review of heavy quarks and new particles; semiclassical results on normalization of bound state wave functions; proton lifetime; quark magnetic moments and E1 radiative transitions in charmonium; lectures on quark models; inverse scattering and the upsilon family; and magnetic moments of quarks in baryons and mesons. In experimental high energy physics, the emphasis has been on strong interactions but also includes several crucial tests of the currently most important theories of elementary particle interactions. Experiments described include: electromagnetic couplings of vector mesons; direct photon production at large transverse momentum; hyperon experiments; spin effects in strong interactions; a dense detector for proton decay; and exclusive processes at large transverse momenta. (GHT)

  17. Experimental Implementation of Underactuated Potential Energy Shaping on a Powered Ankle-Foot Orthosis

    PubMed Central

    Lv, Ge; Zhu, Hanqi; Elery, Toby; Li, Luwei; Gregg, Robert D.

    2016-01-01

    Traditional control methodologies of rehabilitation orthoses/exoskeletons aim at replicating normal kinematics and thus fall into the category of kinematic control. This control paradigm depends on pre-defined reference trajectories, which can be difficult to adjust between different locomotor tasks and human subjects. An alternative control category, kinetic control, enforces kinetic goals (e.g., torques or energy) instead of kinematic trajectories, which could provide a flexible learning environment for the user while freeing up therapists to make corrections. We propose that the theory of underactuated potential energy shaping, which falls into the category of kinetic control, could be used to generate virtual body-weight support for stroke gait rehabilitation. After deriving the nonlinear control law and simulating it on a human-like biped model, we implemented this controller on a powered ankle-foot orthosis that was designed specifically for testing torque control strategies. Experimental results with an able-bodied human subject demonstrate the feasibility of the control approach for both positive and negative virtual body-weight augmentation. PMID:27390625

  18. Oscillatory enhancement of the squeezing flow of yield stress fluids: a novel experimental result

    NASA Astrophysics Data System (ADS)

    Zwick, K. J.; Ayyaswamy, P. S.; Cohen, I. M.

    1997-05-01

    The extrusion of a yield stress fluid from the space between two parallel plates is investigated experimentally. Oscillating the magnitude of the squeezing force about a mean value (F=f[1+[alpha]cos([omega]t)]) was observed to significantly enhance the flow rate of yield stress fluids, while having no effect on the flow rate of Newtonian fluids. This is a novel result. The enhancement depends on the magnitude of the force, the oscillatory frequency and amplitude, the fluid being squeezed, and the thickness of the fluid layer. Non-dimensional results for the various flow quantities have been presented by using the flow predicted for the constant-force squeezing of a Herschel Bulkley yield stress fluid as the reference. In the limit of constant-force squeezing, the present experimental results compare very well with those of our earlier theoretical model for this situation (Zwick, Ayyaswamy & Cohen 1996). The results presented in this paper have significance, among many applications, for injection moulding, in the adhesive bonding of microelectronic chips, and in surgical procedures employed in health care.

  19. Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results

    PubMed Central

    Humada, Ali M.; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M.; Ahmed, Mushtaq N.

    2016-01-01

    A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions. PMID:27035575

  20. Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results.

    PubMed

    Humada, Ali M; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M; Ahmed, Mushtaq N

    2016-01-01

    A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions.

  1. Comparison of Computational and Experimental Microphone Array Results for an 18%-Scale Aircraft Model

    NASA Technical Reports Server (NTRS)

    Lockard, David P.; Humphreys, William M.; Khorrami, Mehdi R.; Fares, Ehab; Casalino, Damiano; Ravetta, Patricio A.

    2015-01-01

    An 18%-scale, semi-span model is used as a platform for examining the efficacy of microphone array processing using synthetic data from numerical simulations. Two hybrid RANS/LES codes coupled with Ffowcs Williams-Hawkings solvers are used to calculate 97 microphone signals at the locations of an array employed in the NASA LaRC 14x22 tunnel. Conventional, DAMAS, and CLEAN-SC array processing is applied in an identical fashion to the experimental and computational results for three different configurations involving deploying and retracting the main landing gear and a part span flap. Despite the short time records of the numerical signals, the beamform maps are able to isolate the noise sources, and the appearance of the DAMAS synthetic array maps is generally better than those from the experimental data. The experimental CLEAN-SC maps are similar in quality to those from the simulations indicating that CLEAN-SC may have less sensitivity to background noise. The spectrum obtained from DAMAS processing of synthetic array data is nearly identical to the spectrum of the center microphone of the array, indicating that for this problem array processing of synthetic data does not improve spectral comparisons with experiment. However, the beamform maps do provide an additional means of comparison that can reveal differences that cannot be ascertained from spectra alone.

  2. Transdermal flux predictions for selected selective oestrogen receptor modulators (SERMs): comparison with experimental results.

    PubMed

    Güngör, Sevgi; Delgado-Charro, M Begoña; Masini-Etévé, Valérie; Potts, Russell O; Guy, Richard H

    2013-12-28

    The aim of this work was to evaluate the feasibility of delivering transdermally a series of highly lipophilic compounds (log P ~4-7), comprising several selective oestrogen receptor modulators and a modified testosterone (danazol). The maximum fluxes of the drugs were predicted theoretically using the modified Potts & Guy algorithm (to determine the permeability coefficient (kp) from water) and the calculated aqueous solubilities. The correction provided by Cleek & Bunge took into account the contribution of the viable epidermal barrier to the skin permeation of highly lipophilic compounds. Experimental measurements of drug fluxes from saturated hydroalcoholic solutions were determined in vitro through excised pig skin. Overall, the predicted fluxes were in good general agreement (within a factor of 10) with the experimental results. Most of the experimental fluxes were greater than those predicted theoretically suggesting that the 70:30 v/v ethanol-water vehicle employed may have had a modest skin penetration enhancement effect. This investigation shows that the transdermal fluxes of highly lipophilic compounds can be reasonably predicted from first principles provided that the viable epidermis, underlying the stratum corneum, is included as a potentially important contributor to the skin's overall barrier function. Furthermore, the absolute values of the measured fluxes, when considered in parallel with previous clinical studies, indicate that it might be feasible to topically deliver a therapeutically useful amount of some of the compounds considered to treat cancerous breast tissue.

  3. LNG fires: a review of experimental results, models and hazard prediction challenges.

    PubMed

    Raj, Phani K

    2007-02-20

    A number of experimental investigations of LNG fires (of sizes 35 m diameter and smaller) were undertaken, world wide, during the 1970s and 1980s to study their physical and radiative characteristics. This paper reviews the published data from several of these tests including from the largest test to date, the 35 m, Montoir tests. Also reviewed in this paper is the state of the art in modeling LNG pool and vapor fires, including thermal radiation hazard modeling. The review is limited to considering the integral and semi-empirical models (solid flame and point source); CFD models are not reviewed. Several aspects of modeling LNG fires are reviewed including, the physical characteristics, such as the (visible) fire size and shape, tilt and drag in windy conditions, smoke production, radiant thermal output, etc., and the consideration of experimental data in the models. Comparisons of model results with experimental data are indicated and current deficiencies in modeling are discussed. The requirements in the US and European regulations related to LNG fire hazard assessment are reviewed, in brief, in the light of model inaccuracies, criteria for hazards to people and structures, and the effects of mitigating circumstances. The paper identifies: (i) critical parameters for which there exist no data, (ii) uncertainties and unknowns in modeling and (iii) deficiencies and gaps in current regulatory recipes for predicting hazards.

  4. Theoretical modelling and experimental results of electromechanical actuation of an elastomer

    NASA Astrophysics Data System (ADS)

    Díaz-Calleja, Ricardo; Llovera-Segovia, Pedro; Dominguez, José Jorge; Carsí Rosique, Marta; Quijano Lopez, Alfredo

    2013-06-01

    Electromechanical actuation is a growing field of research today both for applications or theoretical modelling. The interaction between electric and mechanical constraints has been used for electromechanic actuators or generators based on elastomers. From a theoretical point of view, many recent works have been focused on uniaxial or biaxial stretching of elastomer plates with compliant electrodes. Free stretching or pre-strained samples have been theoretically modelled, mainly by neo-Hookean equations. In this work, we present theoretical and experimental results of electromechanic actuation of an elastomer (the widely used 3M VHB4910, an acrylic foam) in a pre-strained case and a free case. Experimental characterization of the material shows that the Ogden model gives the best accurate fitting of mechanical properties. Thus, a theoretical development based on this model is carried out in order to obtain the curves describing the electromechanical behaviour of the material. The mechanical instability related to wrinkling of the material is theoretically calculated and experimentally verified.

  5. Recovery of yttrium from cathode ray tubes and lamps' fluorescent powders: experimental results and economic simulation.

    PubMed

    Innocenzi, V; De Michelis, I; Ferella, F; Vegliò, F

    2013-11-01

    In this paper, yttrium recovery from fluorescent powder of lamps and cathode ray tubes (CRTs) is described. The process for treating these materials includes the following: (a) acid leaching, (b) purification of the leach liquors using sodium hydroxide and sodium sulfide, (c) precipitation of yttrium using oxalic acid, and (d) calcinations of oxalates for production of yttrium oxides. Experimental results have shown that process conditions necessary to purify the solutions and recover yttrium strongly depend on composition of the leach liquor, in other words, whether the powder comes from treatment of CRTs or lamp. In the optimal experimental conditions, the recoveries of yttrium oxide are about 95%, 55%, and 65% for CRT, lamps, and CRT/lamp mixture (called MIX) powders, respectively. The lower yields obtained during treatments of MIX and lamp powders are probably due to the co-precipitation of yttrium together with other metals contained in the lamps powder only. Yttrium loss can be reduced to minimum changing the experimental conditions with respect to the case of the CRT process. In any case, the purity of final products from CRT, lamps, and MIX is greater than 95%. Moreover, the possibility to treat simultaneously both CRT and lamp powders is very important and interesting from an industrial point of view since it could be possible to run a single plant treating fluorescent powder coming from two different electronic wastes.

  6. Blind deconvolution applied to acoustical systems identification with supporting experimental results

    NASA Astrophysics Data System (ADS)

    Roan, Michael J.; Gramann, Mark R.; Erling, Josh G.; Sibul, Leon H.

    2003-10-01

    Many acoustical applications require the analysis of a signal that is corrupted by an unknown filtering function. Examples arise in the areas of noise or vibration control, room acoustics, structural vibration analysis, and speech processing. Here, the observed signal can be modeled as the convolution of the desired signal with an unknown system impulse response. Blind deconvolution refers to the process of learning the inverse of this unknown impulse response and applying it to the observed signal to remove the filtering effects. Unlike classical deconvolution, which requires prior knowledge of the impulse response, blind deconvolution requires only reasonable prior estimates of the input signal's statistics. The significant contribution of this work lies in experimental verification of a blind deconvolution algorithm in the context of acoustical system identification. Previous experimental work concerning blind deconvolution in acoustics has been minimal, as previous literature concerning blind deconvolution uses computer simulated data. This paper examines experiments involving three classical acoustic systems: driven pipe, driven pipe with open side branch, and driven pipe with Helmholtz resonator side branch. Experimental results confirm that the deconvolution algorithm learns these systems' inverse impulse responses, and that application of these learned inverses removes the effects of the filters.

  7. Supersonic Retropropulsion Experimental Results from the NASA Langley Unitary Plan Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Berry, Scott A.; Rhode, Matthew N.; Edquist, Karl T.; Player, Charles J.

    2011-01-01

    A new supersonic retropropulsion experimental effort, intended to provide code validation data, was recently completed in the Langley Research Center Unitary Plan Wind Tunnel Test Section 2 over the Mach number range from 2.4 to 4.6. The experimental model was designed using insights gained from pre-test computations, which were instrumental for sizing and refining the model to minimize tunnel wall interference and internal flow separation concerns. A 5-in diameter 70-deg sphere-cone forebody with a roughly 10-in long cylindrical aftbody was the baseline configuration selected for this study. The forebody was designed to accommodate up to four 4:1 area ratio supersonic nozzles. Primary measurements for this model were a large number of surface pressures on the forebody and aftbody. Supplemental data included high-speed Schlieren video and internal pressures and temperatures. The run matrix was developed to allow for the quantification of various sources of experimental uncertainty, such as random errors due to run-to-run variations and bias errors due to flow field or model misalignments. Preliminary results and observations from the test are presented, while detailed data and uncertainty analyses are ongoing.

  8. Small Wind Turbine Testing Results from the National Renewable Energy Lab

    SciTech Connect

    Bowen, A.; Huskey, A.; Link, H.; Sinclair, K.; Forsyth, T.; Jager, D.; van Dam, J.; Smith, J.

    2009-07-01

    The independent testing project was established at the National Renewable Energy Laboratory to help reduce the barriers of wind energy expansion. Among these barriers is a lack of independent testing results for small turbines.

  9. Ion velocity distribution functions in argon and helium discharges: detailed comparison of numerical simulation results and experimental data

    NASA Astrophysics Data System (ADS)

    Wang, Huihui; Sukhomlinov, Vladimir S.; Kaganovich, Igor D.; Mustafaev, Alexander S.

    2017-02-01

    Using the Monte Carlo collision method, we have performed simulations of ion velocity distribution functions (IVDF) taking into account both elastic collisions and charge exchange collisions of ions with atoms in uniform electric fields for argon and helium background gases. The simulation results are verified by comparison with the experiment data of the ion mobilities and the ion transverse diffusion coefficients in argon and helium. The recently published experimental data for the first seven coefficients of the Legendre polynomial expansion of the ion energy and angular distribution functions are used to validate simulation results for IVDF. Good agreement between measured and simulated IVDFs shows that the developed simulation model can be used for accurate calculations of IVDFs.

  10. Experimental Energy Levels and Partition Function of the 12C2 Molecule

    NASA Astrophysics Data System (ADS)

    Furtenbacher, Tibor; Szabó, István; Császár, Attila G.; Bernath, Peter F.; Yurchenko, Sergei N.; Tennyson, Jonathan

    2016-06-01

    The carbon dimer, the 12C2 molecule, is ubiquitous in astronomical environments. Experimental-quality rovibronic energy levels are reported for 12C2, based on rovibronic transitions measured for and among its singlet, triplet, and quintet electronic states, reported in 42 publications. The determination utilizes the Measured Active Rotational-Vibrational Energy Levels (MARVEL) technique. The 23,343 transitions measured experimentally and validated within this study determine 5699 rovibronic energy levels, 1325, 4309, and 65 levels for the singlet, triplet, and quintet states investigated, respectively. The MARVEL analysis provides rovibronic energies for six singlet, six triplet, and two quintet electronic states. For example, the lowest measurable energy level of the {{a}}{}3{{{\\Pi }}}{{u}} state, corresponding to the J = 2 total angular momentum quantum number and the F 1 spin-multiplet component, is 603.817(5) cm-1. This well-determined energy difference should facilitate observations of singlet-triplet intercombination lines, which are thought to occur in the interstellar medium and comets. The large number of highly accurate and clearly labeled transitions that can be derived by combining MARVEL energy levels with computed temperature-dependent intensities should help a number of astrophysical observations as well as corresponding laboratory measurements. The experimental rovibronic energy levels, augmented, where needed, with ab initio variational ones based on empirically adjusted and spin-orbit coupled potential energy curves obtained using the Duo code, are used to obtain a highly accurate partition function, and related thermodynamic data, for 12C2 up to 4000 K.

  11. Thermodynamic prediction of glycine polymerization as a function of temperature and pH consistent with experimentally obtained results.

    PubMed

    Kitadai, Norio

    2014-04-01

    Prediction of the thermodynamic behaviors of biomolecules at high temperature and pressure is fundamental to understanding the role of hydrothermal systems in the origin and evolution of life on the primitive Earth. However, available thermodynamic dataset for amino acids, essential components for life, cannot represent experimentally observed polymerization behaviors of amino acids accurately under hydrothermal conditions. This report presents the thermodynamic data and the revised HKF parameters for the simplest amino acid "Gly" and its polymers (GlyGly, GlyGlyGly and DKP) based on experimental thermodynamic data from the literature. Values for the ionization states of Gly (Gly(+) and Gly(-)) and Gly peptides (GlyGly(+), GlyGly(-), GlyGlyGly(+), and GlyGlyGly(-)) were also retrieved from reported experimental data by combining group additivity algorithms. The obtained dataset enables prediction of the polymerization behavior of Gly as a function of temperature and pH, consistent with experimentally obtained results in the literature. The revised thermodynamic data for zwitterionic Gly, GlyGly, and DKP were also used to estimate the energetics of amino acid polymerization into proteins. Results show that the Gibbs energy necessary to synthesize a mole of peptide bond is more than 10 kJ mol(-1) less than previously estimated over widely various temperatures (e.g., 28.3 kJ mol(-1) → 17.1 kJ mol(-1) at 25 °C and 1 bar). Protein synthesis under abiotic conditions might therefore be more feasible than earlier studies have shown.

  12. Comparison of experimental data with results of some drying models for regularly shaped products

    NASA Astrophysics Data System (ADS)

    Kaya, Ahmet; Aydın, Orhan; Dincer, Ibrahim

    2010-05-01

    This paper presents an experimental and theoretical investigation of drying of moist slab, cylinder and spherical products to study dimensionless moisture content distributions and their comparisons. Experimental study includes the measurement of the moisture content distributions of slab and cylindrical carrot, slab and cylindrical pumpkin and spherical blueberry during drying at various temperatures (e.g., 30, 40, 50 and 60°C) at specific constant velocity ( U = 1 m/s) and the relative humidity φ = 30%. In theoretical analysis, two moisture transfer models are used to determine drying process parameters (e.g., drying coefficient and lag factor) and moisture transfer parameters (e.g., moisture diffusivity and moisture transfer coefficient), and to calculate the dimensionless moisture content distributions. The calculated results are then compared with the experimental moisture data. A considerably high agreement is obtained between the calculations and experimental measurements for the cases considered. The effective diffusivity values were evaluated between 0.741 × 10-5 and 5.981 × 10-5 m2/h for slab products, 0.818 × 10-5 and 6.287 × 10-5 m2/h for cylindrical products and 1.213 × 10-7 and 7.589 × 10-7 m2/h spherical products using the Model-I and 0.316 × 10-5-5.072 × 10-5 m2/h for slab products, 0.580 × 10-5-9.587 × 10-5 m2/h for cylindrical products and 1.408 × 10-7-13.913 × 10-7 m2/h spherical products using the Model-II.

  13. Heat transfer from earth-coupled heat exchangers-Experimental and analytical results

    SciTech Connect

    Edwards, J.A.; Vitta, P.K.

    1985-01-01

    Experimental heat transfer results obtained with tubular heat transfer coils buried in soil are presented along with a finite difference simulation model that predicts the heat transfer to or from the buried pipes and the temperature distribution in the soil surrounding the buried pipes. The results were obtained with two different earth-coupled coils. Each coil was fabricated from 2.2 in. (5.6 cm) ID nominal 2 in. diameter cast iron pipe. The length of the heat exchanger for each earth-coupled system was 90 ft. (27.4 m). The earth-coupled coils were buried at a depth of 2.75 ft. (0.84 m) below the surface of the earth. The experimental data cover a time span of seven months and represent operation of the earth-coupled coils at various heat rates. Some of the prime quantities measured on a continuous basis are the earth's temperature at several locations in the vicinity of the buried coils, the far earth temperature, the solar insolation, moisture content of the soil, and the heat transferred to or from the buried coils to the surrounding soil. The finite difference model tracks the temperature distribution in the earth surrounding the coils on a continuous basis and predicts the earth's temperature at many locations adjacent to the earth-coupled coil with a maximum error of 4/sup 0/F (2.2/sup 0/C) during the seven month test. As parameters, the finite difference model included the moisture content of the soil, convection at the surface of the earth, emissivity of the soil, radiation exchange at the air-soil interface, as well as all of the pertinent parameters related to the flow of the heat transfer fluid through the buried pipes. The results presented, both experimental and simulated, have direct application in the design of earth-coupled water-source heat pump systems.

  14. Analysis of the energy impacts of the DOE Appropriate Energy Technology Small Grants Program: methods and results

    SciTech Connect

    Lucarelli, B.; Kessel, J.; Kay, J.; Linse, J.; Tompson, S.; Homer, M.

    1981-02-01

    In 1977, Congress directed DOE to create an energy grants program with the object of funding individuals, small businesses, and nonprofit organizations to develop technologies that use renewable energy resources. The Small Grants Program was created and this report assesses the energy savings potential of the program. The first step in the analysis was to assess the energy-savings potential of 57 projects. Program energy savings were then estimated from project savings using statistical inference. Chapter 2 presents estimates of direct energy savings for the 57 projects and discusses direct energy savings. Chapter 3 discusses the methods and results of the economic analysis. Chapter 4 examines the indirect savings. Because of the large size of the sample, neither project descriptions nor specific details of each project analysis are included. Instead, two examples from the analysis are presented in Chapters 2, 3, and 4 to illustrate the methods. The results of the analysis and key project data are summarized. Chapter 5 presents estimates of program energy savings and the methods used to obtain them. The report concludes with a discussion of how improved project selection can increase program energy savings and present two approaches for conducting future energy-impact studies.

  15. Sizing colloidal particles from their contribution to the effective refractive index: Experimental results

    NASA Astrophysics Data System (ADS)

    Sánchez-Pérez, C.; García-Valenzuela, A.; Sato-Berrú, R. Y.; Flores-Flores, J. O.; Barrera, R. G.

    2011-01-01

    In this work we assess experimentally a new methodology for sizing non-absorbing colloidal particles in situ. It requires measuring the real and imaginary part of the effective refractive index per unit volume fraction occupied by the particles. The mean size and refractive e index of the particles are determined from a suitable model for the effective refractive index of dilute colloids. We present results of experiments made with polystyrene and silica nano-particles and compare them with dynamic light scattering and electron microscopy measurements.

  16. Active vibration absorber for the CSI evolutionary model - Design and experimental results. [Controls Structures Interaction

    NASA Technical Reports Server (NTRS)

    Bruner, Anne M.; Belvin, W. Keith; Horta, Lucas G.; Juang, Jer-Nan

    1991-01-01

    The development of control of large flexible structures technology must include practical demonstrations to aid in the understanding and characterization of controlled structures in space. To support this effort, a testbed facility has been developed to study practical implementation of new control technologies under realistic conditions. The paper discusses the design of a second order, acceleration feedback controller which acts as an active vibration absorber. This controller provides guaranteed stability margins for collocated sensor/actuator pairs in the absence of sensor/actuator dynamics and computational time delay. Experimental results in the presence of these factors are presented and discussed. The robustness of this design under model uncertainty is demonstrated.

  17. Seeded free electron laser operating with two colors: Comments on experimental results

    NASA Astrophysics Data System (ADS)

    Carpanese, M.; Ciocci, F.; Dattoli, G.; Petralia, A.; Petrillo, V.; Torre, A.

    2016-05-01

    Free electron lasers operating with two colors are promising devices for applications. The relevant modelization has provided a good understanding of the underlying physics. In this paper we present an analysis of the experimental results obtained at SPARC_LAB concerning seeded two-colors free electron laser (FEL) operation. The use of an ad hoc developed semi-analytical model based on the small-signal FEL integral equation reproduces most of the observed phenomenology. The paper discusses the reliability of the proposed method, the range of validity and its possible improvement.

  18. Preliminary Results on the Experimental Investigation of the Structure Functions of Bound Nucleons

    SciTech Connect

    Bodek, Arie

    2016-08-01

    We present preliminary results on an experimental study of the nuclear modification of the longitudinal ($\\sigma_L$) and transverse ($\\sigma_T$) structure functions of nucleons bound in nuclear targets. The origin of these modifications (commonly referred as as the EMC effect) is not fully understood. Our measurements of R= $\\sigma_L / \\sigma_T$ for nuclei ($R_A$) and for deuterium ($R_D$) indicate that nuclear modifications of the structure functions of bound nucleons are different for the longitudinal and transverse structure functions, and that contrary to expectation from several theoretical models, $R_A< R_D$.

  19. Comparison of Theoretical Stresses and Deflections of Multicell Wings with Experimental Results Obtained from Plastic Models

    NASA Technical Reports Server (NTRS)

    Zender, George W

    1956-01-01

    The experimental deflections and stresses of six plastic multicell-wing models of unswept, delta, and swept plan form are presented and compared with previously published theoretical results obtained by the electrical analog method. The comparisons indicate that the theory is reliable except for the evaluation of stresses in the vicinity of the leading edge of delta wings and the leading and trailing edges of swept wings. The stresses in these regions are questionable, apparently because of simplifications employed in idealizing the actual structure for theoretical purposes and because of local effects of concentrated loads.

  20. Overview of recent results from the Beam Energy Scan program in the STAR experiment

    NASA Astrophysics Data System (ADS)

    Lipiec, Andrzej

    2016-09-01

    It is believed, that shortly after the Big Bang the Universe existed in the state of the Quark Gluon Plasma, where quarks and gluons act as quasi-free particles. During relativistic heavy ion collisions this state of matter can be reproduced. Quantum Chromo-Dynamics (QCD) calculations show possible existence of the critical point and the 1st order phase transition between hadron gas and QGP. The Relativistic Heavy Ion Collider's (RHIC) program called Beam Energy Scan (BES) was developed for experimental verification of above QCD predictions. Within this program the Solenoidal Tracker At RHIC (STAR) experiment gathered data from gold-gold collisions at √sNN = 7.7, 11.5, 14.5, 19.6, 27, 39, 62.4 and 200 GeV. This data are analysed by STAR Collaboration in search for answers to questions concerning the nuclear matter phases, namely: what is the collision energy for the onset of the QGP formation? What is the nature of a phase transition between QGP and hadron gas? Is there a critical point and if yes, where is it situated? In this proceedings a few of the latest STAR results that address these questions are presented.

  1. Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures.

    PubMed

    Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D; Kuss, Daria J; Billieux, Joël

    2016-06-01

    Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games.

  2. Investigation of sonar transponders for offshore wind farms: modeling approach, experimental setup, and results.

    PubMed

    Fricke, Moritz B; Rolfes, Raimund

    2013-11-01

    The installation of offshore wind farms in the German Exclusive Economic Zone requires the deployment of sonar transponders to prevent collisions with submarines. The general requirements for these systems have been previously worked out by the Research Department for Underwater Acoustics and Marine Geophysics of the Bundeswehr. In this article, the major results of the research project "Investigation of Sonar Transponders for Offshore Wind Farms" are presented. For theoretical investigations a hybrid approach was implemented using the boundary element method to calculate the source directivity and a three-dimensional ray-tracing algorithm to estimate the transmission loss. The angle-dependence of the sound field as well as the weather-dependence of the transmission loss are compared to experimental results gathered at the offshore wind farm alpha ventus, located 45 km north of the island Borkum. While theoretical and experimental results are in general agreement, the implemented model slightly underestimates scattering at the rough sea surface. It is found that the source level of 200 dB re 1 μPa at 1 m is adequate to satisfy the detectability of the warning sequence at distances up to 2 NM (≈3.7 km) within a horizontal sector of ±60° if realistic assumptions about signal-processing and noise are made. An arrangement to enlarge the angular coverage is discussed.

  3. Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures

    PubMed Central

    Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D.; Kuss, Daria J.; Billieux, Joël

    2016-01-01

    Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games. PMID:27156376

  4. On the Dielectric Constant for Acetanilide: Experimental Measurements and Effect on Energy Transport

    NASA Astrophysics Data System (ADS)

    Careri, G.; Compatangelo, E.; Christiansen, P. L.; Halding, J.; Skovgaard, O.

    1987-01-01

    Experimental measurements of the dielectric constant for crystalline acetanilide powder for temperatures ranging from - 140°C to 20°C and for different hydration levels are presented. A Davydov-soliton computer model predicts dramatic changes in the energy transport and storage for typically increased values of the dielectric constant.

  5. Experimental Study of Airfoil Trailing Edge Noise: Instrumentation, Methodology and Initial Results. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Manley, M. B.

    1980-01-01

    The mechanisms of aerodynamic noise generation at the trailing edge of an airfoil is investigated. Instrumentation was designed, a miniature semiconductor strain-gauge pressure transducer and associated electronic amplifier circuitry were designed and tested and digital signal analysis techniques applied to gain insight into the relationship between the dynamic pressure close to the trailing edge and the sound in the acoustic far-field. Attempts are made to verify some trailing-edge noise generation characteristics as theoretically predicted by several contemporary acousticians. It is found that the noise detected in the far-field is comprised of the sum of many uncorrelated emissions radiating from the vicinity of the trailing edge. These emissions appear to be the result of acoustic energy radiation which has been converted by the trailing-edge noise mechanism from the dynamic fluid energy of independent streamwise 'strips' of the turbulent boundary layer flow.

  6. A Comparison of Experimental and Theoretical Results for Labyrinth Gas Seals. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Scharrer, Joseph Kirk

    1987-01-01

    The basic equations are derived for a two control volume model for compressible flow in a labyrinth seal. The flow is assumed to be completely turbulent and isoenergetic. The wall friction factors are determined using the Blasius formula. Jet flow theory is used for the calculation of the recirculation velocity in the cavity. Linearized zeroth and first order perturbation equations are developed for small motion about a centered position by an expansion in the eccentricity ratio. The zeroth order pressure distribution is found by satisfying the leakage equation. The circumferential velocity distribution is determined by satisfying the momentum equations. The first order equations are solved by a separation of variable solution. Integration of the resultant pressure distribution along and around the seal defines the reaction force developed by the seal and the corresponding dynamic coefficients. The results of this analysis are compared to experimental test results.

  7. Swinging Atwood Machine: Experimental and numerical results, and a theoretical study

    NASA Astrophysics Data System (ADS)

    Pujol, O.; Pérez, J. P.; Ramis, J. P.; Simó, C.; Simon, S.; Weil, J. A.

    2010-06-01

    A Swinging Atwood Machine ( SAM) is built and some experimental results concerning its dynamic behaviour are presented. Experiments clearly show that pulleys play a role in the motion of the pendulum, since they can rotate and have non-negligible radii and masses. Equations of motion must therefore take into account the moment of inertia of the pulleys, as well as the winding of the rope around them. Their influence is compared to previous studies. A preliminary discussion of the role of dissipation is included. The theoretical behaviour of the system with pulleys is illustrated numerically, and the relevance of different parameters is highlighted. Finally, the integrability of the dynamic system is studied, the main result being that the machine with pulleys is non-integrable. The status of the results on integrability of the pulley-less machine is also recalled.

  8. The EM/MPM algorithm for segmentation of textured images: analysis and further experimental results.

    PubMed

    Comer, M L; Delp, E J

    2000-01-01

    In this paper we present new results relative to the "expectation-maximization/maximization of the posterior marginals" (EM/MPM) algorithm for simultaneous parameter estimation and segmentation of textured images. The EM/MPM algorithm uses a Markov random field model for the pixel class labels and alternately approximates the MPM estimate of the pixel class labels and estimates parameters of the observed image model. The goal of the EM/MPM algorithm is to minimize the expected value of the number of misclassified pixels. We present new theoretical results in this paper which show that the algorithm can be expected to achieve this goal, to the extent that the EM estimates of the model parameters are close to the true values of the model parameters. We also present new experimental results demonstrating the performance of the EM/MPM algorithm.

  9. Experimental studies of nucleon-nucleon and pion-nucleus interactions at intermediate energies

    SciTech Connect

    Not Available

    1990-10-01

    This report summarizes the work on experimental research in intermediate energy nuclear and particle physics carried out by New Mexico State University in 1988--91. Most of these studies have involved investigations of neutron-proton and pion-nucleus interactions. The neutron-proton research is part of a program of studies of interactions between polarized nucleons that we have been involved with for more than ten years. Its purpose has been to help complete the determination of the full set of ten complex nucleon-nucleon amplitudes at energies up to 800 MeV, as well as to continue investigating the possibility of the existence of dibaryon resonances. The give complex isospin-one amplitudes have been fairly well determined, partly as a result of this work. Our work in this period has involved measurements and analysis of data on elastic scattering and total cross sections for polarized neutrons on polarized protons. The pion-nucleus research continues our studies of this interaction in regions where it has not been well explored. One set of experiments includes studies of pion elastic and double-charge-exchange scattering at energies between 300 and 550 MeV, where our data is unique. Another involves elastic and single-charge-exchange scattering of pions from polarized nuclear targets, a new field of research which will give the first extensive set of information on spin-dependent pion-nucleus amplitudes. Still another involves the first set of detailed studies of the kinematic correlations among particles emitted following pion absorption in nuclei.

  10. Experimental and numerical investigation of a phase change energy storage system

    NASA Astrophysics Data System (ADS)

    Casano, G.; Piva, S.

    2014-04-01

    Latent heat storage systems are an effective way of storing thermal energy. Recently, phase change materials were considered also in the thermal control of compact electronic devices. In the present work a numerical and experimental investigation is presented for a solid-liquid phase change process dominated by heat conduction. In the experimental arrangement a plane slab of PCM is heated from above with an on-off thermal power simulating the behaviour of an electronic device. A two-dimensional finite volume code is used for the solution of the corresponding mathematical model. The comparison between numerical predictions and experimental data shows a good agreement. Finally, in order to characterize this thermal energy storage system, the time distribution of latent and sensible heat is analyzed.

  11. Crystal growth of pure substances: Phase-field simulations in comparison with analytical and experimental results

    NASA Astrophysics Data System (ADS)

    Nestler, B.; Danilov, D.; Galenko, P.

    2005-07-01

    A phase-field model for non-isothermal solidification in multicomponent systems [SIAM J. Appl. Math. 64 (3) (2004) 775-799] consistent with the formalism of classic irreversible thermodynamics is used for numerical simulations of crystal growth in a pure material. The relation of this approach to the phase-field model by Bragard et al. [Interface Science 10 (2-3) (2002) 121-136] is discussed. 2D and 3D simulations of dendritic structures are compared with the analytical predictions of the Brener theory [Journal of Crystal Growth 99 (1990) 165-170] and with recent experimental measurements of solidification in pure nickel [Proceedings of the TMS Annual Meeting, March 14-18, 2004, pp. 277-288; European Physical Journal B, submitted for publication]. 3D morphology transitions are obtained for variations in surface energy and kinetic anisotropies at different undercoolings. In computations, we investigate the convergence behaviour of a standard phase-field model and of its thin interface extension at different undercoolings and at different ratios between the diffuse interface thickness and the atomistic capillary length. The influence of the grid anisotropy is accurately analyzed for a finite difference method and for an adaptive finite element method in comparison.

  12. Preliminary Test Results of Heshe Hydrogeological Experimental Well Station in Taiwan

    NASA Astrophysics Data System (ADS)

    Chuang, P.; Liu, C.; Lin, M.; Chan, W.; Lee, T.; Chia, Y.; Teng, M.; Liu, C.

    2013-12-01

    Safe disposal of radioactive waste is a critical issue for the development of nuclear energy. The design of final disposal system is based on the concept of multiple barriers which integrate the natural barriers and engineering barriers for long-term isolation of radioactive wastes. As groundwater is the major medium that can transport radionuclides to our living environment, it is essential to characterize groundwater flow at the disposal site. Taiwan is located at the boundary between the Eurasian plate and the Philippine Sea plate. Geologic formations are often fractured due to tectonic compression and extension. In this study, a well station for the research and development of hydrogeological techniques was established at the Experimental Forest of the National Taiwan University in central Taiwan. There are 10 testing wells, ranging in depth from 25 m to 100 m, at the station. The bedrock beneath the regolith is highly fractured mudstone. As fracture is the preferential pathway of the groundwater flow, the focus of in-situ tests is to investigate the location of permeable fractures and the connection of permeable fractures. Several field tests have been conducted, including geophysical logging, heat-pulse flowmeter, hydraulic test, tracer test and double packer test, for the development of advanced technologies to detect the preferential groundwater flow in fractured rocks.

  13. Comparison of experimental and analytical results for free vibration of laminated composite plates

    SciTech Connect

    Maryuama, Koichi; Narita, Yoshihiro; Ichinomiya, Osamu

    1995-11-01

    Fibrous composite materials are being increasingly employed in high performance structures, including pressured vessel and piping applications. These materials are usually used in the form of laminated flat or curved plates, and the understanding of natural frequencies and the corresponding mode shapes is essential to a reliable structural design. Although many references have been published on analytical study of laminated composite plates, a limited number of experimental studies have appeared for dealing with vibration characteristics of the plates. This paper presents both experimental and analytical results for the problems. In the experiment, the holographic interferometry is used to measure the resonant frequencies and corresponding mode shapes of six-layered CFRP (carbon fiber reinforced plastic) composite plates. The material constants of a lamina are calculated from fiber and matrix material constants by using some different composite rules. With the calculated constants, the natural frequencies of the laminated CFRP plates are theoretically determined by the Ritz method. From the comparison of two sets of the results, the effect of choosing different composite rules is discussed in the vibration study of laminated composite plates.

  14. Natural frequencies of two bubbles in a compliant tube: Analytical, simulation, and experimental results

    PubMed Central

    Jang, Neo W.; Zakrzewski, Aaron; Rossi, Christina; Dalecki, Diane; Gracewski, Sheryl

    2011-01-01

    Motivated by various clinical applications of ultrasound contrast agents within blood vessels, the natural frequencies of two bubbles in a compliant tube are studied analytically, numerically, and experimentally. A lumped parameter model for a five degree of freedom system was developed, accounting for the compliance of the tube and coupled response of the two bubbles. The results were compared to those produced by two different simulation methods: (1) an axisymmetric coupled boundary element and finite element code previously used to investigate the response of a single bubble in a compliant tube and (2) finite element models developed in comsol Multiphysics. For the simplified case of two bubbles in a rigid tube, the lumped parameter model predicts two frequencies for in- and out-of-phase oscillations, in good agreement with both numerical simulation and experimental results. For two bubbles in a compliant tube, the lumped parameter model predicts four nonzero frequencies, each asymptotically converging to expected values in the rigid and compliant limits of the tube material. PMID:22088008

  15. Influence of a stationary magnetic field on water relations in lettuce seeds. Part II: experimental results.

    PubMed

    Reina, F G; Pascual, L A; Fundora, I A

    2001-12-01

    An experimental study on water absorption by lettuce seeds previously treated in a stationary magnetic field of 0-10 mT is presented. A significant increase in the rate with which the seeds absorb water is observed in the interval 0-10 mT of magnetic treatment. An increment in the total mass of absorbed water in this interval is also observed. These results are consistent with the reports on the increase of germination rate of the seeds, and the theoretical calculation of the variations induced by magnetic fields in the ionic currents across the cellular membrane. The fields originate in changes in the ionic concentration and thus in the osmotic pressure which regulates the entrance of water to the seeds. The good correlation between the theoretical approach and experimental results provides strong evidence that the magnetic field alters the water relations in seeds, and this effect may be the explanation of the reported alterations in germination rate of seeds by the magnetic field.

  16. Tilted wheel satellite attitude control with air-bearing table experimental results

    NASA Astrophysics Data System (ADS)

    Inumoh, Lawrence O.; Forshaw, Jason L.; Horri, Nadjim M.

    2015-12-01

    Gyroscopic actuators for satellite control have attracted significant research interest over the years, but their viability for the control of small satellites has only recently started to become clear. Research on variable speed gyroscopic actuators has long been focused on single gimbal actuators; double gimbal actuators typically operate at constant wheel spin rate and allow tilt angle ranges far larger than the ranges needed to operate most satellite missions. This research examines a tilted wheel, a newly proposed type of inertial actuator that can generate torques in all three principal axes of a rigid satellite using a spinning wheel and a double tilt mechanism. The tilt mechanism tilts the angular momentum vector about two axes providing two degree of freedom control, while variation of the wheel speed provides the third. The equations of motion of the system lead to a singularity-free system during nominal operation avoiding the need for complex steering logic. This paper describes the hardware design of the tilted wheel and the experimental setup behind both standalone and spherical air-bearing tables used to test it. Experimental results from the air bearing table are provided with the results depicting the high performance capabilities of the proposed actuator in torque generation.

  17. Thermal conductivity of silicic tuffs: predictive formalism and comparison with preliminary experimental results

    SciTech Connect

    Lappin, A. R.

    1980-07-01

    Performance of both near- and far-field thermomechanical calculations to assess the feasibility of waste disposal in silicic tuffs requires a formalism for predicting thermal conductivity of a broad range of tuffs. This report summarizes the available thermal conductivity data for silicate phases that occur in tuffs and describes several grain-density and conductivity trends which may be expected to result from post-emplacement alteration. A bounding curve is drawn that predicts the minimum theoretical matrix (zero-porosity) conductivity for most tuffs as a function of grain density. Comparison of experimental results with this curve shows that experimental conductivities are consistently lower at any given grain density. Use of the lowered bounding curve and an effective gas conductivity of 0.12 W/m{sup 0}C allows conservative prediction of conductivity for a broad range of tuff types. For the samples measured here, use of the predictive curve allows estimation of conductivity to within 15% or better, with one exception. Application and possible improvement of the formalism are also discussed.

  18. Experimental Impeller Fragmentation of Iliocaval Thrombosis Under Tulip Filter Protection: Preliminary Results

    SciTech Connect

    Schmitz-Rode, Thomas; Vorwerk, Dierk; Schuermann, Karl; Guenther, Rolf W.

    1996-04-15

    Purpose: To assess the efficacy of catheter fragmentation of massive caval thrombosis and of filter protection against procedure-related pulmonary embolism. Methods: In 10 sheep, a self-expanding tulip-shaped filter made from Wallstent mesh (diameter 25 mm) was introduced from the right jugular approach into the proximal inferior vena cava. Experimentally induced massive iliocaval thrombosis was fragmented by an impeller catheter (expanded diameter 14 mm), which was advanced coaxially through the sheath of the expanded filter. Post-procedural cavography and pulmonary angiography were performed to document the extent of caval recanalization and pulmonary embolism. Results: In all cases, impeller fragmentation cleared the inferior vena cava and the iliac veins of thrombi completely. Fragments washed downstream were trapped in the filter. In two of the first cases, parts of the clots caused pulmonary embolism before the filter was in place. Further events were avoided by a modification of the experimental setup. Except for some small peripheral perfusion defects in two cases, pulmonary angiograms did not show any incidence of pulmonary embolism. Conclusion: Our preliminary results suggest that impeller fragmentation of iliocaval thrombi under tulip filter protection is effective and does not cause significant pulmonary embolism.

  19. Natural frequencies of two bubbles in a compliant tube: analytical, simulation, and experimental results.

    PubMed

    Jang, Neo W; Zakrzewski, Aaron; Rossi, Christina; Dalecki, Diane; Gracewski, Sheryl

    2011-11-01

    Motivated by various clinical applications of ultrasound contrast agents within blood vessels, the natural frequencies of two bubbles in a compliant tube are studied analytically, numerically, and experimentally. A lumped parameter model for a five degree of freedom system was developed, accounting for the compliance of the tube and coupled response of the two bubbles. The results were compared to those produced by two different simulation methods: (1) an axisymmetric coupled boundary element and finite element code previously used to investigate the response of a single bubble in a compliant tube and (2) finite element models developed in comsol Multiphysics. For the simplified case of two bubbles in a rigid tube, the lumped parameter model predicts two frequencies for in- and out-of-phase oscillations, in good agreement with both numerical simulation and experimental results. For two bubbles in a compliant tube, the lumped parameter model predicts four nonzero frequencies, each asymptotically converging to expected values in the rigid and compliant limits of the tube material.

  20. Fuel-rich, catalytic reaction experimental results. [fuel development for high-speed civil transport aircraft

    NASA Technical Reports Server (NTRS)

    Rollbuhler, Jim

    1991-01-01

    Future aeropropulsion gas turbine combustion requirements call for operating at very high inlet temperatures, pressures, and large temperature rises. At the same time, the combustion process is to have minimum pollution effects on the environment. Aircraft gas turbine engines utilize liquid hydrocarbon fuels which are difficult to uniformly atomize and mix with combustion air. An approach for minimizing fuel related problems is to transform the liquid fuel into gaseous form prior to the completion of the combustion process. Experimentally obtained results are presented for vaporizing and partially oxidizing a liquid hydrocarbon fuel into burnable gaseous components. The presented experimental data show that 1200 to 1300 K reaction product gas, rich in hydrogen, carbon monoxide, and light-end hydrocarbons, is formed when flowing 0.3 to 0.6 fuel to air mixes through a catalyst reactor. The reaction temperatures are kept low enough that nitrogen oxides and carbon particles (soot) do not form. Results are reported for tests using different catalyst types and configurations, mass flowrates, input temperatures, and fuel to air ratios.

  1. Transport of fluorobenzoate tracers in a vegetated hydrologic control volume: 1. Experimental results

    NASA Astrophysics Data System (ADS)

    Queloz, Pierre; Bertuzzo, Enrico; Carraro, Luca; Botter, Gianluca; Miglietta, Franco; Rao, P. S. C.; Rinaldo, Andrea

    2015-04-01

    This paper reports about the experimental evidence collected on the transport of five fluorobenzoate tracers injected under controlled conditions in a vegetated hydrologic volume, a large lysimeter (fitted with load cells, sampling ports, and an underground chamber) where two willows prompting large evapotranspiration fluxes had been grown. The relevance of the study lies in the direct and indirect measures of the ways in which hydrologic fluxes, in this case, evapotranspiration from the upper surface and discharge from the bottom drainage, sample water and solutes in storage at different times under variable hydrologic forcings. Methods involve the accurate control of hydrologic inputs and outputs and a large number of suitable chemical analyses of water samples in discharge waters. Mass extraction from biomass has also been performed ex post. The results of the 2 year long experiment established that our initial premises on the tracers' behavior, known to be sorption-free under saturated conditions which we verified in column leaching tests, were unsuitable as large differences in mass recovery appeared. Issues on reactivity thus arose and were addressed in the paper, in this case attributed to microbial degradation and solute plant uptake. Our results suggest previously unknown features of fluorobenzoate compounds as hydrologic tracers, potentially interesting for catchment studies owing to their suitability for distinguishable multiple injections, and an outlook on direct experimental closures of mass balance in hydrologic transport volumes involving fluxes that are likely to sample differently stored water and solutes.

  2. Analysis and comparison of experimental and simulated results for an omnidirectional free space optical receiver architecture

    NASA Astrophysics Data System (ADS)

    Murshid, Syed H.; Lovell, Gregory L.; Finch, Michael F.

    2014-09-01

    Lasercomm or Free Space Optical (FSO) communication has the potential to provide fiber optic data rates without the need for wired physical connectivity. This paper investigates the feasibility of an Omnidirectional FSO (O-FSO) communications link that utilizes fiber bundles for improved omni-directionality and compares experimental data with modeled results. Current state of the art O-FSO link ranges are limited to 100 meters or so, with data rates of only a few100 kbits/sec. The proposed architecture is formed from commercially available fiber bundle that collects omnidirectional light due to the hemispheric nature of the fiber bundle by exploiting the acceptance cones of the individual fiber exposed to the optical radiation. The experimental transmitter is composed of an LED source that is driven by an On-Off-Keying signal. This paper presents the received optical power while varying the range between the transmitter and receiver. The omni-directionality of this architecture is also verified. The measured results are then compared to the model predictions for omni-directionality and range.

  3. Acylguanidine Beta Secretase 1 Inhibitors: A Combined Experimental and Free Energy Perturbation Study.

    PubMed

    Keränen, Henrik; Pérez-Benito, Laura; Ciordia, Myriam; Delgado, Francisca; Steinbrecher, Thomas B; Oehlrich, Daniel; van Vlijmen, Herman W T; Trabanco, Andrés A; Tresadern, Gary

    2017-03-14

    A series of acylguanidine beta secretase 1 (BACE1) inhibitors with modified scaffold and P3 pocket substituent was synthesized and studied with free energy perturbation (FEP) calculations. The resulting molecules showed potencies in enzymatic BACE1 inhibition assays up to 1 nM. The correlation between the predicted activity from the FEP calculations and the experimental activity was good for the P3 pocket substituents. The average mean unsigned error (MUE) between prediction and experiment was 0.68 ± 0.17 kcal/mol for the default 5 ns lambda window simulation time improving to 0.35 ± 0.13 kcal/mol for 40 ns. FEP calculations for the P2' pocket substituents on the same acylguanidine scaffold also showed good agreement with experiment and the results remained stable with repeated simulations and increased simulation time. It proved more difficult to use FEP calculations to study the scaffold modification from increasing 5 to 6 and 7 membered-rings. Although prediction and experiment were in agreement for short 2 ns simulations, as the simulation time increased the results diverged. This was improved by the use of a newly developed "Core Hopping FEP+" approach, which also showed improved stability in repeat calculations. The origins of these differences along with the value of repeat and longer simulation times are discussed. This work provides a further example of the use of FEP as a computational tool for molecular design.

  4. Experimental results on the design for the APS PID global orbit control system.

    SciTech Connect

    Chung, Y.; Kirchman, J. A.

    1997-12-05

    The Advanced Photon Source third generation synchrotrons light source needs a stabilized particle beam position to produce high brightness and low emittance radiation. Global orbit correction control is introduced and is utilized to satisfy the demanding needs of the accelerator. This paper presents the experimental results for determining an effective and optimal controller to meet the global orbit correction requirements. These requirements include frequency/time domain demands consisting of vibrational noise attenuation, limiting of controller gains for stability and improving the system time response. Experiments were conducted with a digital signal processor implementing various PID sets to make comparisons between simulations and experiments. Measurements at these PID sets supported the results of software simulation.

  5. Synthetic aperture LADAR at 1550 nm: system demonstration, imaging processing and experimental result

    NASA Astrophysics Data System (ADS)

    Li, Guangzuo; Wang, Ran; Wang, Peisi; Zhang, Keshu; Wu, Yirong

    2016-10-01

    In this manuscript, we propose and experimentally demonstrate our synthetic aperture LADAR (SAL) system. The system could obtain imageries in a few milliseconds with resolution of 5 cm from a long distance. Fine resolution in the range dimension was obtained by transmitting LADAR signal with large bandwidth. While in the cross-range dimension, the large synthetic aperture diameter provided fine resolution. By employing continuous translational motion of SAL system, a large aperture diameter was obtained through synthetic aperture processing. So the diffraction limit of real aperture diameter was overcome and finer resolution was achieved. Indoor and outdoor experiments were both performed and the corresponding results were showed. Results validated the feasibility of our system and processing algorithm.

  6. Comparison of results of experimental research with numerical calculations of a model one-sided seal

    NASA Astrophysics Data System (ADS)

    Joachimiak, Damian; Krzyślak, Piotr

    2015-06-01

    Paper presents the results of experimental and numerical research of a model segment of a labyrinth seal for a different wear level. The analysis covers the extent of leakage and distribution of static pressure in the seal chambers and the planes upstream and downstream of the segment. The measurement data have been compared with the results of numerical calculations obtained using commercial software. Based on the flow conditions occurring in the area subjected to calculations, the size of the mesh defined by parameter y+ has been analyzed and the selection of the turbulence model has been described. The numerical calculations were based on the measurable thermodynamic parameters in the seal segments of steam turbines. The work contains a comparison of the mass flow and distribution of static pressure in the seal chambers obtained during the measurement and calculated numerically in a model segment of the seal of different level of wear.

  7. Experimental results for improving the matrix condition using a hybrid optical system.

    PubMed

    Klapp, Iftach; Mendlovic, David

    2012-03-01

    We present preliminary experimental results for implementing the "blurred trajectories" method on three parallel optics (PO) systems. The "main" system and "auxiliary" optics were simple laboratory graded lenses attached to an iris diaphragm. When applying the blurred trajectories method we first show an improvement in the matrix condition, as the matrix condition number decreased in a range of factors of 3 to 418 relative to the main system. Following that, image restoration by weak regularization was performed so that the system matrix condition dominated the restoration process. It was shown that the restoration results of the PO are better than those of the main system and the auxiliary optics separately. In addition, the quality of the restoration follows the system's matrix condition. The improvement in the matrix condition achieved by the PO system improved the immunity to detection noise. Finally, a comparison to Wiener filtering restoration shows that it is also generally inferior to the proposed method.

  8. The Langley Research Center CSI phase-0 evolutionary model testbed-design and experimental results

    NASA Technical Reports Server (NTRS)

    Belvin, W. K.; Horta, Lucas G.; Elliott, K. B.

    1991-01-01

    A testbed for the development of Controls Structures Interaction (CSI) technology is described. The design philosophy, capabilities, and early experimental results are presented to introduce some of the ongoing CSI research at NASA-Langley. The testbed, referred to as the Phase 0 version of the CSI Evolutionary model (CEM), is the first stage of model complexity designed to show the benefits of CSI technology and to identify weaknesses in current capabilities. Early closed loop test results have shown non-model based controllers can provide an order of magnitude increase in damping in the first few flexible vibration modes. Model based controllers for higher performance will need to be robust to model uncertainty as verified by System ID tests. Data are presented that show finite element model predictions of frequency differ from those obtained from tests. Plans are also presented for evolution of the CEM to study integrated controller and structure design as well as multiple payload dynamics.

  9. Carbon fiber composites inspection and defect characterization using active infrared thermography: numerical simulations and experimental results.

    PubMed

    Fernandes, Henrique; Zhang, Hai; Figueiredo, Alisson; Ibarra-Castanedo, Clemente; Guimarares, Gilmar; Maldague, Xavier

    2016-12-01

    Composite materials are widely used in the aeronautic industry. One of the reasons is because they have strength and stiffness comparable to metals, with the added advantage of significant weight reduction. Infrared thermography (IT) is a safe nondestructive testing technique that has a fast inspection rate. In active IT, an external heat source is used to stimulate the material being inspected in order to generate a thermal contrast between the feature of interest and the background. In this paper, carbon-fiber-reinforced polymers are inspected using IT. More specifically, carbon/PEEK (polyether ether ketone) laminates with square Kapton inserts of different sizes and at different depths are tested with three different IT techniques: pulsed thermography, vibrothermography, and line scan thermography. The finite element method is used to simulate the pulsed thermography experiment. Numerical results displayed a very good agreement with experimental results.

  10. Survey of Experimental Results in High-Contrast Imaging for Future Exoplanet Missions

    NASA Technical Reports Server (NTRS)

    Lawson, P. R.; Belikov, R.; Cash, W.; Clampin, M.; Glassman, T.; Guyon, O.; Kasdin, N. J.; Kern, B. D.; Lyon, R.; Mawet, D.; Moody, D.; Samuele, R.; Serabyn, E.; Sirbu, D.; Trauger, J.

    2013-01-01

    We present and compare experimental results in high contrast imaging representing the state of the art in coronagraph and starshade technology. These experiments have been undertaken with the goal of demonstrating the capability of detecting Earth-like planets around nearby Sun-like stars. The contrast of an Earth seen in reflected light around a Sun-like star would be about 1.2 x 10(exp -10). Several of the current candidate technologies now yield raw contrasts of 1.0 x 10(exp -9) or better, and so should enable the detection of Earths, assuming a gain in sensitivity in post-processing of a factor of 10. We present results of coronagraph and starshade experiments conducted at visible and infrared wavelengths. Cross-sections of dark fields are directly compared as a function of field angle and bandwidth. The strength and differences of the techniques are compared.

  11. Beam-waveguide antenna performance predictions with comparisons to experimental results

    NASA Technical Reports Server (NTRS)

    Bathker, Dan A.; Veruttipong, Watt; Otoshi, Tom Y.; Cramer, Paul W., Jr.

    1992-01-01

    An overview of a NASA/JPL antenna project is presented, with specific focus on the methodology used to predict the microwave performance of a 34-m-diameter beam-waveguide (BWG) reflector antenna, designated DSS 13 (Deep Space Station 13). DSS 13 is the R&D facility serving the NASA/JPL Deep Space Network. Microwave performance predictions as well as a summary of test results for the antenna are given. The antenna has Cassegrain and centerline BWG operating modes at X-band (8.450-GHz) and Ka-band (32-GHz) frequencies. The performance predictions regarding antenna area efficiencies, corresponding beampeak gains, and for several (but not all) operating noise temperatures are found to agree reasonably well with the corresponding experimental results.

  12. Fault detection, isolation and reconfiguration in FTMP Methods and experimental results. [fault tolerant multiprocessor

    NASA Technical Reports Server (NTRS)

    Lala, J. H.

    1983-01-01

    The Fault-Tolerant Multiprocessor (FTMP) is a highly reliable computer designed to meet a goal of 10 to the -10th failures per hour and built with the objective of flying an active-control transport aircraft. Fault detection, identification, and recovery software is described, and experimental results obtained by injecting faults in the pin level in the FTMP are presented. Over 21,000 faults were injected in the CPU, memory, bus interface circuits, and error detection, masking, and error reporting circuits of one LRU of the multiprocessor. Detection, isolation, and reconfiguration times were recorded for each fault, and the results were found to agree well with earlier assumptions made in reliability modeling.

  13. Experimental and Computational Studies of High Energy Density Plasma Streams Ablated from Fine Wires

    SciTech Connect

    Greenly, John B.; Seyler, Charles

    2014-03-30

    thermal energy; reconnection and outflow are triggered when the current begins to decrease and the electric field reverses. The reconnecting flow is driven by both magnetic and thermal pressure forces, and it has been found to be possible to vary the configuration so that one or the other dominates. The magnetic null extends into a current sheet that is heated and radiates strongly, with supersonic outflows. This is the first study of reconnection in this HED plasma regime. This compressible, radiative regime, and the triggering mechanism, may be relevant to solar and astrophysical processes. The PERSEUS extended MHD code has been developed for simulation of these phenomena, and will continue to be used and further developed to help interpret and understand experimental results, as well as to guide experimental design. The code is well-suited to simulations of shocks, and includes Hall and electron inertia physics that appear to be of importance in a number of ablation flow regimes, and definitely in the reconnection regime when gradient scales are comparable to the ion inertial scale. During the final year, our graduate student supported by this grant completed a new version of PERSEUS with the finite volume computational scheme replaced by a discontinuous Galerkin method that gives much less diffusive behavior and allows faster run time and higher spatial resolution. Thecode is now being used to study shock structures produced in the outflow region of the reconnection regime.

  14. Experimental testing of ab initio potential energy surfaces: Stereodynamics of NO(A2Σ+) + Ne inelastic scattering at multiple collision energies

    NASA Astrophysics Data System (ADS)

    Luxford, Thomas F. M.; Sharples, Thomas R.; McKendrick, Kenneth G.; Costen, Matthew L.

    2016-11-01

    We present a crossed molecular beam velocity-map ion imaging study of state-to-state rotational energy transfer of NO(A2Σ+, v = 0, N = 0, j = 0.5) in collisions with Ne atoms. From these measurements, we report differential cross sections and angle-resolved rotational angular momentum alignment moments for product states N' = 3 and 5-10 for collisions at an average energy of 523 cm-1, and N' = 3 and 5-14 for collisions at an average energy of 1309 cm-1, respectively. The experimental results are compared to the results of close-coupled quantum scattering calculations on two literature ab initio potential energy surfaces (PESs) [Pajón-Suárez et al., Chem. Phys. Lett. 429, 389 (2006) and Cybulski and Fernández, J. Phys. Chem. A 116, 7319 (2012)]. The differential cross sections from both experiment and theory show clear rotational rainbow structures at both collision energies, and comparison of the angles observed for the rainbow peaks leads to the conclusion that Cybulski and Fernández PES better represents the NO(A2Σ+)-Ne interaction at the collision energies used here. Sharp, forward scattered (<10°), peaks are observed in the experimental differential cross sections for a wide range of N' at both collision energies, which are not reproduced by theory on either PES. We identify these as L-type rainbows, characteristic of attractive interactions, and consistent with a shallow well in the collinear Ne-N-O geometry, similar to that calculated for the NO(A2Σ+)-Ar surface [Kłos et al., J. Chem. Phys. 129, 244303 (2008)], but absent from both of the NO(A2Σ+)-Ne surfaces tested here. The angle-resolved alignment moments calculated by quantum scattering theory are generally in good agreement with the experimental results, but both experiment and quantum scattering theories are dramatically different to the predictions of a classical rigid-shell, kinematic-apse conservation model. Strong oscillations are resolved in the experimental alignment moments as a

  15. Experimental testing of ab initio potential energy surfaces: Stereodynamics of NO(A(2)Σ(+)) + Ne inelastic scattering at multiple collision energies.

    PubMed

    Luxford, Thomas F M; Sharples, Thomas R; McKendrick, Kenneth G; Costen, Matthew L

    2016-11-07

    We present a crossed molecular beam velocity-map ion imaging study of state-to-state rotational energy transfer of NO(A(2)Σ(+), v = 0, N = 0, j = 0.5) in collisions with Ne atoms. From these measurements, we report differential cross sections and angle-resolved rotational angular momentum alignment moments for product states N' = 3 and 5-10 for collisions at an average energy of 523 cm(-1), and N' = 3 and 5-14 for collisions at an average energy of 1309 cm(-1), respectively. The experimental results are compared to the results of close-coupled quantum scattering calculations on two literature ab initio potential energy surfaces (PESs) [Pajón-Suárez et al., Chem. Phys. Lett. 429, 389 (2006) and Cybulski and Fernández, J. Phys. Chem. A 116, 7319 (2012)]. The differential cross sections from both experiment and theory show clear rotational rainbow structures at both collision energies, and comparison of the angles observed for the rainbow peaks leads to the conclusion that Cybulski and Fernández PES better represents the NO(A(2)Σ(+))-Ne interaction at the collision energies used here. Sharp, forward scattered (<10°), peaks are observed in the experimental differential cross sections for a wide range of N' at both collision energies, which are not reproduced by theory on either PES. We identify these as L-type rainbows, characteristic of attractive interactions, and consistent with a shallow well in the collinear Ne-N-O geometry, similar to that calculated for the NO(A(2)Σ(+))-Ar surface [Kłos et al., J. Chem. Phys. 129, 244303 (2008)], but absent from both of the NO(A(2)Σ(+))-Ne surfaces tested here. The angle-resolved alignment moments calculated by quantum scattering theory are generally in good agreement with the experimental results, but both experiment and quantum scattering theories are dramatically different to the predictions of a classical rigid-shell, kinematic-apse conservation model. Strong oscillations are resolved in the experimental alignment

  16. Experimental Results and Predictive Calculations for Pinhole Collimators Used in Small Animal Nuclear Imaging*

    NASA Astrophysics Data System (ADS)

    Ng, Luke; Welsh, Robert E.; Bradley, Eric L.; Saha, Margaret S.; Kross, Brian; Majewski, Stan; Popov, Vladimir; Smith, Mark F.; Weisenberger, Andrew G.; Wojcik, Randolph

    2001-04-01

    Biological ligands tagged with ^125 I have been used in studies including comparisons between normal and diabetic mice in vivo. In order to enhance the image of the mouse pancreas we have tested a number of pinhole collimators coupled to two types of position sensitive photomultiplier tube. Various shapes of pinhole have been tested. Results will be described and discussed. *Supported in part by The Department of Energy, The National Science Foundation, The American Diabetes Association, The Howard Hughes Foundation, The Virginia Commonwealth Health Research Board and the Thomas F. and Kate Miller Jeffress Memorial Trust.

  17. Heat Transfer Enhancement for Finned-Tube Heat Exchangers with Vortex Generators: Experimental and Numerical Results

    SciTech Connect

    O'Brien, James Edward; Sohal, Manohar Singh; Huff, George Albert

    2002-08-01

    A combined experimental and numerical investigation is under way to investigate heat transfer enhancement techniques that may be applicable to large-scale air-cooled condensers such as those used in geothermal power applications. The research is focused on whether air-side heat transfer can be improved through the use of finsurface vortex generators (winglets,) while maintaining low heat exchanger pressure drop. A transient heat transfer visualization and measurement technique has been employed in order to obtain detailed distributions of local heat transfer coefficients on model fin surfaces. Pressure drop measurements have also been acquired in a separate multiple-tube row apparatus. In addition, numerical modeling techniques have been developed to allow prediction of local and average heat transfer for these low-Reynolds-number flows with and without winglets. Representative experimental and numerical results presented in this paper reveal quantitative details of local fin-surface heat transfer in the vicinity of a circular tube with a single delta winglet pair downstream of the cylinder. The winglets were triangular (delta) with a 1:2 height/length aspect ratio and a height equal to 90% of the channel height. Overall mean fin-surface Nusselt-number results indicate a significant level of heat transfer enhancement (average enhancement ratio 35%) associated with the deployment of the winglets with oval tubes. Pressure drop measurements have also been obtained for a variety of tube and winglet configurations using a single-channel flow apparatus that includes four tube rows in a staggered array. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided. Heat transfer and pressure-drop results have been obtained for flow Reynolds numbers based on channel height and mean flow velocity ranging from 700 to 6500.

  18. Neuronal and glial changes in the brain resulting from explosive blast in an experimental model.

    PubMed

    Goodrich, James A; Kim, Jung H; Situ, Robert; Taylor, Wesley; Westmoreland, Ted; Du, Fu; Parks, Steven; Ling, Geoffrey; Hwang, Jung Y; Rapuano, Amedeo; Bandak, Faris A; de Lanerolle, Nihal C

    2016-11-24

    Mild traumatic brain injury (mTBI) is the signature injury in warfighters exposed to explosive blasts. The pathology underlying mTBI is poorly understood, as this condition is rarely fatal and thus postmortem brains are difficult to obtain for neuropathological studies. Here we report on studies of an experimental model with a gyrencephalic brain that is exposed to single and multiple explosive blast pressure waves. To determine injuries to the brain resulting from the primary blast, experimental conditions were controlled to eliminate any secondary or tertiary injury from blasts. We found small but significant levels of neuronal loss in the hippocampus, a brain area that is important for cognitive functions. Furthermore, neuronal loss increased with multiple blasts and the degree of neuronal injury worsened with time post-blast. This is consistent with our findings in the blast-exposed human brain based on magnetic resonance spectroscopic imaging. The studies on this experimental model thus confirm what has been presumed to be the case with the warfighter, namely that exposure to multiple blasts causes increased brain injury. Additionally, as in other studies of both explosive blast as well as closed head mTBI, we found astrocyte activation. Activated microglia were also prominent in white matter tracts, particularly in animals exposed to multiple blasts and at long post-blast intervals, even though injured axons (i.e. β-APP positive) were not found in these areas. Microglial activation appears to be a delayed response, though whether they may contribute to inflammation related injury mechanism at even longer post-blast times than we tested here, remains to be explored. Petechial hemorrhages or other gross signs of vascular injury were not observed in our study. These findings confirm the development of neuropathological changes due to blast exposure. The activation of astrocytes and microglia, cell types potentially involved in inflammatory processes, suggest an

  19. Recovery of yttrium from cathode ray tubes and lamps’ fluorescent powders: experimental results and economic simulation

    SciTech Connect

    Innocenzi, V. De Michelis, I.; Ferella, F.; Vegliò, F.

    2013-11-15

    Highlights: • Fluorescent powder of lamps. • Fluorescent powder of cathode ray rubes. • Recovery of yttrium from fluorescent powders. • Economic simulation for the processes to recover yttrium from WEEE. - Abstract: In this paper, yttrium recovery from fluorescent powder of lamps and cathode ray tubes (CRTs) is described. The process for treating these materials includes the following: (a) acid leaching, (b) purification of the leach liquors using sodium hydroxide and sodium sulfide, (c) precipitation of yttrium using oxalic acid, and (d) calcinations of oxalates for production of yttrium oxides. Experimental results have shown that process conditions necessary to purify the solutions and recover yttrium strongly depend on composition of the leach liquor, in other words, whether the powder comes from treatment of CRTs or lamp. In the optimal experimental conditions, the recoveries of yttrium oxide are about 95%, 55%, and 65% for CRT, lamps, and CRT/lamp mixture (called MIX) powders, respectively. The lower yields obtained during treatments of MIX and lamp powders are probably due to the co-precipitation of yttrium together with other metals contained in the lamps powder only. Yttrium loss can be reduced to minimum changing the experimental conditions with respect to the case of the CRT process. In any case, the purity of final products from CRT, lamps, and MIX is greater than 95%. Moreover, the possibility to treat simultaneously both CRT and lamp powders is very important and interesting from an industrial point of view since it could be possible to run a single plant treating fluorescent powder coming from two different electronic wastes.

  20. EASE (Experimental Assembly of Structures in EVA) overview of selected results

    NASA Technical Reports Server (NTRS)

    Akin, David L.

    1987-01-01

    Experimental Assembly of Structures in EVA (EASE) objectives, experimental protocol, neutral buoyancy simulation, task time distribution, assembly task performance, metabolic rate/biomedical readouts are summarized. This presentation is shown in charts, figures, and graphs.