WorldWideScience

Sample records for current experimental results

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S. J., E-mail: sjwang@nfri.re.kr; Kim, J.; Jeong, J. H.; Kim, H. J.; Joung, M.; Bae, Y. S.; Kwak, J. G. [National Fusion Research Institute, Daejoen, 305-806 (Korea, Republic of)

    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.

  2. First experimental results with the Current Limit Avoidance System at the JET tokamak

    Energy Technology Data Exchange (ETDEWEB)

    De Tommasi, G. [Associazione EURATOM-ENEA-CREATE, Università di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); Galeani, S. [Dipartimento di Informatica, Sistemi e Produzione, Università di Roma, Tor Vergata, Rome (Italy); Jachmich, S. [Association EURATOM-Belgian State, Koninklijke Militaire School - Ecole Royale Militaire, B-1000 Brussels (Belgium); Joffrin, E. [IRFM-CEA, Centre de Cadarache, 13108 Saint-paul-lez-Durance (France); Lennholm, M. [EFDA Close Support Unit, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); European Commission, B-1049 Brussels (Belgium); Lomas, P.J. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Neto, A.C. [Associazione EURATOM-IST, Instituto de Plasmas e Fusao Nuclear, IST, 1049-001 Lisboa (Portugal); Maviglia, F. [Associazione EURATOM-ENEA-CREATE, Via Claudio 21, 80125 Napoli (Italy); McCullen, P. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Pironti, A. [Associazione EURATOM-ENEA-CREATE, Università di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); Rimini, F.G. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Sips, A.C.C. [European Commission, B-1049 Brussels (Belgium); Varano, G.; Vitelli, R. [Dipartimento di Informatica, Sistemi e Produzione, Università di Roma, Tor Vergata, Rome (Italy); Zaccarian, L. [CNRS, LAAS, 7 Avenue du Colonel Roche, F-31400 Toulouse (France); Universitè de Toulouse, LAAS, F-31400 Toulouse (France)

    2013-06-15

    The Current Limit Avoidance System (CLA) has been recently deployed at the JET tokamak to avoid current saturations in the poloidal field (PF) coils when the eXtreme Shape Controller is used to control the plasma shape. In order to cope with the current saturation limits, the CLA exploits the redundancy of the PF coils system to automatically obtain almost the same plasma shape using a different combination of currents in the PF coils. In the presence of disturbances it tries to avoid the current saturations by relaxing the constraints on the plasma shape control. The CLA system has been successfully implemented on the JET tokamak and fully commissioned in 2011. This paper presents the first experimental results achieved in 2011–2012 during the restart and the ITER-like wall campaigns at JET.

  3. Water-waves on linear shear currents. A comparison of experimental and numerical results.

    Science.gov (United States)

    Simon, Bruno; Seez, William; Touboul, Julien; Rey, Vincent; Abid, Malek; Kharif, Christian

    2016-04-01

    Propagation of water waves can be described for uniformly sheared current conditions. Indeed, some mathematical simplifications remain applicable in the study of waves whether there is no current or a linearly sheared current. However, the widespread use of mathematical wave theories including shear has rarely been backed by experimental studies of such flows. New experimental and numerical methods were both recently developed to study wave current interactions for constant vorticity. On one hand, the numerical code can simulate, in two dimensions, arbitrary non-linear waves. On the other hand, the experimental methods can be used to generate waves with various shear conditions. Taking advantage of the simplicity of the experimental protocol and versatility of the numerical code, comparisons between experimental and numerical data are discussed and compared with linear theory for validation of the methods. ACKNOWLEDGEMENTS The DGA (Direction Générale de l'Armement, France) is acknowledged for its financial support through the ANR grant N° ANR-13-ASTR-0007.

  4. Experimental Results on Current-Driven Turbulence in Plasmas - a Survey

    NARCIS (Netherlands)

    Dekluiver, H.; Perepelkin, N. F.; Hirose, A.

    1991-01-01

    The experimental consequences of plasma turbulence driven by a current parallel to a magnetic field and concurrent anomalous plasma heating are reviewed, with an attempt to deduce universalities in key parameters such as the anomalous electrical conductivities observed in diverse devices. It has

  5. Experimental results of current distribution in Rutherford-type LHC cables

    CERN Document Server

    Verweij, A P

    2000-01-01

    Current distribution among the wires of multi-strand superconducting cables is an important item for accelerator magnets. A non-uniform distribution could cause additional field distortions in the magnet bore and can as well be one of the reasons of premature quenching. Since two years electrical measurements on superconducting Rutherford-type cables are performed at CERN as part of the reception tests for the Large Hadron Collider (LHC). Cable samples of 2.4 m length are tested at currents up to 32 kA, temperatures around 1.9 and 4.3 K, and fields up to 10 T, applied perpendicularly as well as parallel to the broad face of the cable. Last year, an array of 24 Hall probes was installed in the test set-up in order to measure the self-field of the cable samples along one cable pitch. Each of the probes measures the local field generated by the current in the strands close by, and the results of the all probes reflect therefore the distribution of the strand currents. Experiments are done varying the applied fie...

  6. Behavior of a DC zero-flux current sensor; Magnetic field analysis and comparison with experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Campostrini, P.; Sonato, P. (Istituto Gas Ionizzati del CNR, Padova (IT))

    1991-09-01

    In this paper the magnetic section of the finite-element ANSYS code, and in particular its optimization feature has been used to predict the behaviour of a zero-flux current sensor, briefly described, which is intended to be used in a fusion experiment to measure pulsed currents up to 50 kA, over a bandwidth from DC to 10 k Hz. The computed results fit well with those coming from experimental tests performed on a prototype.

  7. Experimental studies on benzene carcinogenicity at the Bologna Institute of Oncology: current results and ongoing research.

    Science.gov (United States)

    Maltoni, C; Conti, B; Cotti, G; Belpoggi, F

    1985-01-01

    In 1977 Maltoni and Scarnato were the first to demonstrate that benzene is an experimental carcinogen in rats. With that and other experiments, Maltoni et al have shown that benzene administered by ingestion (stomach tube) or inhalation is a multipotential carcinogen in rats (of two different strains) and mice and produces a variety of tumors, namely: Zymbal gland carcinomas, oral and nasal cavity carcinomas, skin carcinomas, acanthomas, dysplasias and carcinomas of forestomach, mammary malignant tumors, hepatomas, liver angiosarcomas, hemolymphoreticular neoplasias, and pulmonary tumors. The incidence of Zymbal gland carcinomas and carcinomas of the oral and nasal cavities is affected by the length of treatment by inhalation and by the age of animals. However, the available epidemiological and experimental data at present do not provide precise information on the risk of doses around or below 10 ppm. Long-term carcinogenicity bioassays at 50, 25, 10, 5 and 1 ppm may be helpful for scientific risk assessment. In addition, these experiments have shown that toluene, xylene, and ethylbenzene, at high concentrations, cause an increase in the number of total malignant tumors.

  8. Experimental Results of a DC Bus Voltage Level Control for a Load-Controlled Marine Current Energy Converter

    Directory of Open Access Journals (Sweden)

    Johan Forslund

    2015-05-01

    Full Text Available This paper investigates three load control methods for a  marine current energy converter using a vertical axis current  turbine (VACT mounted on a permanent magnet synchronous generator  (PMSG. The three cases are; a fixed AC load, a fixed pulse width  modulated (PWM DC load and DC bus voltage control of a DC  load. Experimental results show that the DC bus voltage control  reduces the variations of rotational speed by a factor of 3.5 at the cost  of slightly increased losses in the generator and transmission lines.  For all three cases, the tip speed ratio \\(\\lambda\\ can be kept close to  the expected \\(\\lambda_{opt}\\. The power coefficient is estimated to be  0.36 at \\(\\lambda_{opt}\\; however, for all three cases, the average  extracted power was about \\(\\sim 19\\\\%. A maximum power point  tracking (MPPT system, with or without water velocity measurement,  could increase the average extracted power.

  9. Recent experimental results of effects of perfluoroalkyl substances in laboratory animals - Relation to current regulations and guidance values.

    Science.gov (United States)

    Lilienthal, Hellmuth; Dieter, Hermann H; Hölzer, Jürgen; Wilhelm, Michael

    2017-03-02

    The detection of perfluoroalkyl substances (PFAS) in surface and drinking water from various countries raised the attention to the presence of these chemicals in environmental probes and led to several regulatory actions to limit exposure in human beings. There was particular concern about perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), due to their former wide-spread use. Recently, several institutions published revisions of former regulatory or recommended maximum concentrations in drinking water and food, which are markedly lower than the former values. The present short overview describes the current regulations for PFAS and compares them with the outcome of several experimental studies in laboratory animals at low-level exposure to PFOA and PFOS. In addition, regulations for short-chain PFAS are presented which, due to lack of toxicological information, are evaluated according to the concepts of Threshold of Toxicological Concern (TTC) or the Health-related Indication Values (HRIV).

  10. Thermodiffusion in concentrated ferrofluids: A review and current experimental and numerical results on non-magnetic thermodiffusion

    Energy Technology Data Exchange (ETDEWEB)

    Sprenger, Lisa, E-mail: Lisa.Sprenger@tu-dresden.de; Lange, Adrian; Odenbach, Stefan [Institute of Fluid Mechanics, Chair of Magnetofluiddynamics, Measuring and Automation Technology, TU Dresden, 01062 Dresden (Germany)

    2013-12-15

    Ferrofluids are colloidal suspensions consisting of magnetic nanoparticles dispersed in a carrier liquid. Their thermodiffusive behaviour is rather strong compared to molecular binary mixtures, leading to a Soret coefficient (S{sub T}) of 0.16 K{sup −1}. Former experiments with dilute magnetic fluids have been done with thermogravitational columns or horizontal thermodiffusion cells by different research groups. Considering the horizontal thermodiffusion cell, a former analytical approach has been used to solve the phenomenological diffusion equation in one dimension assuming a constant concentration gradient over the cell's height. The current experimental work is based on the horizontal separation cell and emphasises the comparison of the concentration development in different concentrated magnetic fluids and at different temperature gradients. The ferrofluid investigated is the kerosene-based EMG905 (Ferrotec) to be compared with the APG513A (Ferrotec), both containing magnetite nanoparticles. The experiments prove that the separation process linearly depends on the temperature gradient and that a constant concentration gradient develops in the setup due to the separation. Analytical one dimensional and numerical three dimensional approaches to solve the diffusion equation are derived to be compared with the solution used so far for dilute fluids to see if formerly made assumptions also hold for higher concentrated fluids. Both, the analytical and numerical solutions, either in a phenomenological or a thermodynamic description, are able to reproduce the separation signal gained from the experiments. The Soret coefficient can then be determined to 0.184 K{sup −1} in the analytical case and 0.29 K{sup −1} in the numerical case. Former theoretical approaches for dilute magnetic fluids underestimate the strength of the separation in the case of a concentrated ferrofluid.

  11. SAA drift: Experimental results

    Science.gov (United States)

    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. RESULTS OF CALCULATION-EXPERIMENTAL INVESTIGATIONS OF ELECTRO-THERMAL RESISTIBILITY OF SHEET STEEL SAMPLES TO ACTION OF RATIONED COMPONENTS OF PULSED CURRENT OF ARTIFICIAL LIGHTING

    Directory of Open Access Journals (Sweden)

    M.I. Baranov

    2016-06-01

    Full Text Available Purpose. Calculation and experimental researches of the electro-thermal resistibility of the steel sheet samples to action standard pulse current components of the artificial lightning with amplitude-time parameters (ATP, corresponded the requirements of normative documents of USA for SAE ARP 5412 & SAE ARP 5416. Methodology. Electrophysics bases of technique of high tensions and large impulsive currents (LIC, and also scientific and technical bases of planning of devices of high-voltage impulsive technique and measuring in them LIC. Сurrent amplitude ImA=±200 kA (with a tolerance of ±10 %; current action integral JA=2∙106 A2•s (with a tolerance of ±20 %; time, corresponding to the amplitude of the current ImA, tmA≤50 microseconds; the duration of the current flow τpA≤500 microseconds. Results. The results of the evaluation of the calculated and experimental studies of electro-thermal resistance of the samples of plates measuring 0,5 m  0,5 m stainless steel 1 mm thickness to the action on them artificial lightning impulse currents with rationed ATP on the requirements of normative documents of USA for SAE ARP 5412 & SAE ARP 5416. A pulse A- component have a first amplitude 192 kA, the corresponding time of 34 μs, and the duration aperiodic component amplitude 804 A, corresponding to the time 9 ms. It has been shown that the long C- component current of artificial lightning can lead to keyhole these samples. The diameter of the holes in this thin steel sheet, which is formed during the flow of current C- components can reach 15 mm. The results of calculation and experiment agree within 28 %. Originality. For the first time in world practice on the generator large pulsed currents experimental studies of resistibility of sheet steel samples to the action of artificial lightning currents with critical parameters. Practical value. Using the results obtained in the practice of lightning protection will significantly improve the

  13. Plan Merging: Experimental results

    NARCIS (Netherlands)

    De Weerdt, M.M.; Van der Krogt, R.P.J.; Zutt, J.

    2003-01-01

    In this paper we discuss the results of a plan merging algorithm. This algorithm coordinates the plans of multiple, autonomous agents, each able to independently find a plan. This algorithm is evaluated using realistic data from a taxi company. We show that when we allow passengers to be a few minut

  14. Identification of steel bars immersed in reinforced concrete based on experimental results of eddy current testing and artificial neural network analysis

    Science.gov (United States)

    de Alcantara, Naasson

    2013-03-01

    This paper presents an experimental research on the use of eddy current testing (ECT) and artificial neural networks (ANNs) in order to identify the gauge and position of steel bars immersed in concrete structures. The paper presents details of the ECT probe and concrete specimens constructed for the tests, and a study about the influence of the concrete on the values of measured voltages. After this, new measurements were done with a greater number of specimens, simulating a field condition and the results were used to generate training and validation vectors for multilayer perceptron ANNs. The results show a high percentage of correct identification with respect to both, the gauge of the bar and of the thickness of the concrete cover.

  15. NOAA NOS SOS, EXPERIMENTAL - Currents

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA NOS SOS server is part of the IOOS DIF SOS Project. The stations in this dataset have currents data. *These services are for testing and evaluation use...

  16. Top Quark Current Experimental Status

    CERN Document Server

    Juste, A

    2006-01-01

    Ten years after its discovery at the Tevatron collider, we still know little about the top quark. Its large mass suggests it may play a key role in the mechanism of Electroweak Symmetry Breaking (EWSB), or open a window of sensitivity to new physics related to EWSB and preferentially coupled to it. To determine whether this is the case, precision measurements of top quark properties are necessary. The high statistics samples being collected by the Tevatron experiments during Run II start to incisively probe the top quark sector. This report summarizes the experimental status of the top quark, focusing in particular on the recent measurements from the Tevatron.

  17. Numerical evaluation of currents induced in a worker by ELF non-uniform electric fields in high voltage substations and comparison with experimental results.

    Science.gov (United States)

    Tarao, Hiroo; Korpinen, Leena H; Kuisti, Harri A; Hayashi, Noriyuki; Elovaara, Jarmo A; Isaka, Katsuo

    2013-01-01

    An ungrounded human, such as a substation worker, receives contact currents when touching a grounded object in electric fields. In this article, contact currents and internal electric fields induced in the human when exposed to non-uniform electric fields at 50 Hz are numerically calculated. This is done using a realistic human model standing at a distance of 0.1-0.5 m from the grounded conductive object. We found that the relationship between the external electric field strength and the contact current obtained by calculation is in good agreement with previous measurements. Calculated results show that the contact currents largely depend on the distance, and that the induced electric fields in the tissues are proportional to the contact current regardless of the non-uniformity of the external electric field. Therefore, it is concluded that the contact current, rather than the spatial average of the external electric field, is more suitable for evaluating electric field dosimetry of tissues. The maximum induced electric field appears in the spinal cord in the central nervous system tissues, with the induced electric field in the spinal cord approaching the basic restriction (100 mV/m) of the new 2010 International Commission on Non-Ionizing Radiation Protection guidelines for occupational exposure, if the contact current is 0.5 mA. Copyright © 2012 Wiley Periodicals, Inc.

  18. Experimental results on evaporation waves

    Science.gov (United States)

    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).

  19. Majorana Thermosyphon Prototype Experimental Results

    Energy Technology Data Exchange (ETDEWEB)

    Fast, James E.; Reid, Douglas J.; Aguayo Navarrete, Estanislao

    2010-12-17

    Objective The Majorana demonstrator will operate at liquid Nitrogen temperatures to ensure optimal spectrometric performance of its High Purity Germanium (HPGe) detector modules. In order to transfer the heat load of the detector module, the Majorana demonstrator requires a cooling system that will maintain a stable liquid nitrogen temperature. This cooling system is required to transport the heat from the detector chamber outside the shield. One approach is to use the two phase liquid-gas equilibrium to ensure constant temperature. This cooling technique is used in a thermosyphon. The thermosyphon can be designed so the vaporization/condensing process transfers heat through the shield while maintaining a stable operating temperature. A prototype of such system has been built at PNNL. This document presents the experimental results of the prototype and evaluates the heat transfer performance of the system. The cool down time, temperature gradient in the thermosyphon, and heat transfer analysis are studied in this document with different heat load applied to the prototype.

  20. CSCM: Experimental and Simulation Results

    CERN Document Server

    Rowan, S; Brodzinski, K; Charifoulline, Z; Denz, R; Romera, I; Roger, V; Siemko, A; Schmidt, R; Steckert, J; Thiesen, H; Verweij, A; Willering, G; Wollmann, D; Zerlauth, M; Pfeffer, H

    2014-01-01

    The Copper-Stabilizer Continuity Measurement (CSCM) was devised to obtain a direct and complete qualification of the continuity in the 13 kA bypass circuits of the LHC, especially in the copper-stabilizer of the busbar joints and the bolted connections in the diodeleads, as well as in lyra connections. The circuit under test is brought to about 20 K, a voltage is applied to open the diodes by-passing the magnets, and the low-inductance circuit is powered according to a pre-defined series of current profiles. The profiles are designed to successively increase the thermal load on the busbar joints up to a level that corresponds to worst-case operating conditions at nominal energy. In this way, the circuit is tested for thermal runaways in the joints - the very process that could prove catastrophic if it occurred under nominal conditions with the full stored energy of the circuit. A type test of the CSCM was successfully carried out in April 2013 on one main dipole and one main quadrupole circuit of the LHC. Thi...

  1. CALCULATION AND EXPERIMENTAL ESTIMATION OF RESULTS OF ELECTRO-THERMAL ACTION OF RATIONED BY THE INTERNATIONAL STANDARD IEC 62305-1-2010 IMPULSE CURRENT OF SHORT BLOW OF ARTIFICIAL LIGHTNING ON THE THIN-WALLED COVERAGE FROM STAINLESS STEEL

    Directory of Open Access Journals (Sweden)

    M. I. Baranov

    2017-03-01

    Full Text Available Purpose. Calculation and experimental researches of electro-thermal resistibility of the pre-production thin-walled sheet models of outward roof of height technical buildings from stainless steel are easily soiled 12Х18Н10Т to direct action on them rationed by the International Standard IEC 62305-1-2010 aperiodic impulse of current of short bow of artificial lightning of temporal form 10/350 μs with the proper admittances on his peak-temporal parameters (PTP. Methodology. Electrophysics bases of technique of high voltage and large impulsive currents (LIC, and also scientific and technical bases of planning of high-voltage impulsive devices and measuring methods in them LIC with followings below extreme PTP: amplitude of impulse of current of ImL=200 кА (with admittance ±10 %; integral of action of impulse of current of JL=10·106 A2·s (with admittance ±35 %; %; duration of wavefront current of T1=10 μs (with admittance ±20 %; time, proper amplitude of impulse of current of ImL, tmL≤24 μs (with admittance ±20 %; duration of flowing of impulse of current of T2=350 μs (with admittance ±10 %. Results. The results of evaluation calculation and experimental researches of electro-thermal resistibility of the indicated pre-production sheet models are resulted measuring in the plan of 0,5 x 0,5 m from stainless steel are easily soiled the 12Х18Н10Т thickness of 1 mm to action on them of aperiodic impulse of current of short blow of artificial lightning with rationed PTP on the requirements of the International Standard IEC 62305-1-2010. In high current experiments amplitude of ImL of the aperiodic rationed impulse of current of artificial lightning of temporal form of T1/T2=15 μs/315 μs changed in the range of (100-184 кА. The integral of action of JL of impulse of current for I-IV of levels of protection of lightning of technical objects (TO numeral made from 2,32·106 А2·s to 7,88·106 А2·s, and the flowing through the

  2. Experimental results on quadratic assignment problem

    Directory of Open Access Journals (Sweden)

    N.P. Nikolov

    1999-08-01

    Full Text Available The paper presents experimental results on quadratic assignment problem. The "scanning area" method formulated for radioelectronic equipment design is applied. For all more complex tests ours results are better or coincident with the ones known in literature. Conclusion concerning the effectiveness of method are given.

  3. Statistical combination of experimental results in ATLAS

    CERN Document Server

    Gadatsch, Stefan; The ATLAS collaboration

    2016-01-01

    The combination of experimental results requires a careful statistical treatment. We review the methods and tools used in ATLAS for the statistical combination of measurements and of limits on new physics. We highlight the methods used in the recent combination of ATLAS and CMS measurements of the Higgs boson production/decay rates and the constraints on the Higgs coupling parameters.

  4. RESULTS OF AUTOMOBILE BIOGAS ENGINE EXPERIMENTAL INVESTIGATION

    Directory of Open Access Journals (Sweden)

    Abramchuk, F.

    2013-06-01

    Full Text Available The results of experimental study of automotive ICE running using biogas with different volume content of CO2 are presented. Recommendations for choosing the values of air-fuel ratios and ignition timings for different operating modes of the automotive biogas engine depending on fuel chemical composition are given.

  5. A partially static turbine - first experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Grassmann, H.; Bet, F.; Cabras, G.; Ceschia, M.; Cobai, D.; DelPapa, C. [Universitadi Udine (Italy). Dpto. di Fisica

    2003-09-01

    Recently it has been shown in a fluidodynamic simulation, that a wing-profiled structure of rather small size placed in the vicinity of a wind turbine augments the power of the wind turbine. In this paper we present the first experimental results from a prototype. (author)

  6. Microwave radiometry for humanitarian demining: experimental results

    Science.gov (United States)

    Johnson, Joel T.; Kim, Hyunjin; Wiggins, David R.; Cheon, Yonghun

    2002-08-01

    Previous modeling studies have indicated that a multi-frequency radiometer could prove advantageous for humanitarian demining due to the oscillatory patterns in brightness temperature versus frequency that would be observed in the presence of a sub-surface target. Initial experimental results are reported in this paper from a multi-frequency radiometer (MFRAD) system operating at 19 frequencies in the 2.1-6.5 GHz band. The basic design of MFRAD is reviewed, and the calibration and noise background removal procedures discussed. Experimental results with sub-surface metallic and styrofoam targets are then provided that demonstrate the predicted oscillatory behavior. An FFT-based detection algorithm is also described and applied to measured data. Further plans for experiments and tests with this system are also detailed.

  7. PDX experimental results in FY82

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, S.M.; Bell, M.; Bol, K.; Bitter, M.; Buchenauer, D.; Budny, R.; Brau, K.; Crowley, T.; Davis, S.; Dylla, H.

    1983-08-01

    This report presents a detailed summary of the major experimental results of PDX in FY82 and represents the efforts of the entire PDX group. Topics covered include ..beta..-scaling and fishbone studies, fluctuations, disruptions, impurities and impurity transport, power handling, limiter conditioning, edge studies, plasma fueling, counter-injection, and diagnostic development. A less detailed version will appear as the FY82 PDX contribution to the PPPL Annual Report.

  8. Predictions of High Energy Experimental Results

    Directory of Open Access Journals (Sweden)

    Comay E.

    2010-10-01

    Full Text Available Eight predictions of high energy experimental results are presented. The predictions contain the $Sigma ^+$ charge radius and results of two kinds of experiments using energetic pionic beams. In addition, predictions of the failure to find the following objects are presented: glueballs, pentaquarks, Strange Quark Matter, magnetic monopoles searched by their direct interaction with charges and the Higgs boson. The first seven predictions rely on the Regular Charge-Monopole Theory and the last one relies on mathematical inconsistencies of the Higgs Lagrangian density.

  9. Predictions of High Energy Experimental Results

    Directory of Open Access Journals (Sweden)

    Comay E.

    2010-10-01

    Full Text Available Eight predictions of high energy experimental results are presented. The predictions contain the + charge radius and results of two kinds of experiments using energetic pionic beams. In addition, predictions of the failure to find the following objects are presented: glueballs, pentaquarks, Strange Quark Matter, magnetic monopoles searched by their direct interaction with charges and the Higgs boson. The first seven predictions rely on the Regular Charge-Monopole Theory and the last one relies on mathematical inconsistencies of the Higgs Lagrangian density.

  10. Experimental Results from Railgun Firings Involving Magnetic Flux Probes.

    Science.gov (United States)

    1986-12-01

    report is unlimited KEYWORDS Railgun Accelerators Current Distribution Electromagnetic Launchers Magnetic Fields Plasma Armature COSATI GROUPS 2009 1906...series are presented. 2 3. EXPERIMENTAL DETAILS The power source for the RAPID railgun fi] used in the MRAP series consisted of a 2.0 mF capacitor bank...MEUKOURNE, VICTORIA TECHNICAL NOTE MRL-TN-509 EXPERIMENTAL RESULTS FROM RAILGUN FIRINGS INVOLVING MAGNETIC FLUX PROBES V. Kowalenko THE UNITED STATES

  11. Some observational results of sea storm current

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ INTRODUCTION Dr. Hollister, a marine geologist of the Woods Hole Oceanographic Institution, first pointed out that there was ocean storm current in the ocean. He found out the wavy texture in the seabed core samples, and suggested that this wavy texture was caused by the high speed sea current in remote antiquity. He then suggested a bold hypothesis that there existed a benthic storm current near the ocean bottom, and presented this hypothesis at the IUGG conference held at San Francisco in 1963. Unfortunately, the attention was not drawn to the hypothesis at the conference, and the hypothesis was criticized as a sheer nonsense.

  12. Joint voltages resulting from lightning currents.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, William Arthur; Warne, Larry Kevin; Merewether, Kimball O.; Chen, Kenneth C.

    2007-03-01

    Simple formulas are given for the interior voltages appearing across bolted joints from exterior lightning currents. External slot and bolt inductances as well as internal slot and bolt diffusion effects are included. Both linear and ferromagnetic wall materials are considered. A useful simplification of the slot current distribution into linear stripline and cylindrical parts (near the bolts) allows the nonlinear voltages to be estimated in closed form.

  13. Experimental results from a stepped frequency GPR

    Directory of Open Access Journals (Sweden)

    G. M. Signore

    2003-06-01

    Full Text Available In the framework of a nationally funded project, a Ground Penetrating Radar (GPR has been developed by the Italian Consortium for Research on Advanced Remote Sensing Systems (CO.RI.S.T.A.. The system was described in a previous paper (Alberti et al., 2002. As new aspects, the system is a stepped frequency GPR that can work both in gated and ungated mode, and the antennas can be moved automatically in a controlled fashion. As aspects of geophysical interest, the system is exploitable in situations wherein a high resolution and a shallow penetration in the soil (a few meters are required. Possibly, this is an example of probing a landscape. This paper completes the results of Alberti et al. (2002, wherein laboratory tests where described, by providing the main results obtained during an outdoor experimental campaign, performed fi rst in a controlled site and then in an archaeological site.

  14. Experimental results on the Pygmy Dipole Resonance

    Directory of Open Access Journals (Sweden)

    Savran Deniz

    2014-03-01

    Full Text Available The so-called Pygmy Dipole Resonance, an additional structure of low-lying electric dipole strength, has attracted strong interest in the last years. Different experimental approaches have been used in the last decade in order to investigate this new interesting nuclear excitation mode. In this contribution an overview on the available experimental data is given.

  15. Superspreading: molecular dynamics simulations and experimental results

    Science.gov (United States)

    Theodorakis, Panagiotis; Kovalchuk, Nina; Starov, Victor; Muller, Erich; Craster, Richard; Matar, Omar

    2015-11-01

    The intriguing ability of certain surfactant molecules to drive the superspreading of liquids to complete wetting on hydrophobic substrates is central to numerous applications that range from coating flow technology to enhanced oil recovery. Recently, we have observed that for superspreading to occur, two key conditions must be simultaneously satisfied: the adsorption of surfactants from the liquid-vapor surface onto the three-phase contact line augmented by local bilayer formation. Crucially, this must be coordinated with the rapid replenishment of liquid-vapor and solid-liquid interfaces with surfactants from the interior of the droplet. Here, we present the structural characteristics and kinetics of the droplet spreading during the different stages of this process, and we compare our results with experimental data for trisiloxane and poly oxy ethylene surfactants. In this way, we highlight and explore the differences between surfactants, paving the way for the design of molecular architectures tailored specifically for applications that rely on the control of wetting. EPSRC Platform Grant MACIPh (EP/L020564/).

  16. Current results and trends in platform switching

    Directory of Open Access Journals (Sweden)

    Hadi Salimi

    2011-01-01

    Full Text Available The platform switching (PLS concept was introduced in the literature in 2005. The biological benefits and clinical effectiveness of the PLS technique have been established by several studies. In this article different aspects of PLS concept are discussed. Crestal bone loss, biologic width, and stress distribution in this concept are comprehensively reviewed. In this article the relative published articles from 1990 to 2011 have been evaluated by electronic search. Because of controversial results especially in immediate loading and animal studies, further modified research is needed to establish the mechanism and effect of the PLS technique. Essential changes in studies including using the control group for accurate interpretation of results and long-term observation, particularly through, randomized, prospective, multicenter trials with large numbers of participants, and implants are necessary.

  17. Experimental results on chiral magnetic and vortical effects

    CERN Document Server

    Wang, Gang

    2016-01-01

    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. 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 needed to eliminate the existing uncertainties in the interpretation of the data.

  18. Experimental observation of direct current voltage-induced phase synchronization

    Indian Academy of Sciences (India)

    Haihong Li; Weiqing Liu; Qiongling Dai; Jinghua Xiao

    2006-09-01

    The dynamics of two uncoupled distinct Chua circuits driven by a common direct current voltage is explored experimentally. It was found that, with increasing current intensity, the dominant frequencies of these two Chua circuits will first vary at different speeds, approach an identical value for a certain current intensity and then separate. Techniques such as synchronization index and phase difference distribution were employed to analyze the phase coherence between these two Chua circuits.

  19. Candela photo-injector experimental results

    CERN Document Server

    Travier, C; Cayla, J N; Leblond, B; Georges, P; Thomas, P; Travier, C; Boy, L; Cayla, J N; Leblond, B; Georges, P; Thomas, P

    1995-01-01

    The CANDELA photo-injector is a two cell S-band photo-injector. The copper cathode is illuminated by a 500 fs Ti:sapphire laser. This paper presents energy spectrum measurements of the dark current and intense electron emission that occurs when the laser power density is very high.

  20. Experimental Investigation of Turbulence Specifications of Turbidity Currents

    Directory of Open Access Journals (Sweden)

    B Firoozabadi

    2010-01-01

    Full Text Available The present study investigates the turbulence characteristic of turbidity current experimentally. The three-dimensional Acoustic-Doppler Velocimeter (ADV was used to measure the instantaneous velocity and characteristics of the turbulent flow. The experiments were conducted in a three-dimensional channel for different discharge flows, concentrations, and bed slopes. Results are expressed at various distances from the inlet, for all flow rates, slopes and concentrations as the distribution of turbulence energy, Reynolds stress and the turbulent intensity. It was concluded that the maximum turbulence intensity happens in both the interface and near the wall. Also, it was observed that the turbulence intensity reaches its minimum where maximum velocity occurs.

  1. Experimental Results of Schlicher's Thrusting Antenna

    Science.gov (United States)

    Fralick, Gustave C.; Niedra, Janis M.

    2001-01-01

    Experiments were conducted to test the claims by Rex L. Schlicher, et al., (Patent 5,142,86 1) that a certain antenna geometry produces thrust greatly exceeding radiation reaction, when driven by repetitive, fast rise, and relatively slower decay current pulses. In order to test this hypothesis, the antenna was suspended by strings as a 3 in pendulum. Current pulses were fed to the antenna along the suspension path by a very flexible coaxial line constructed from loudspeaker cable and copper braid sheath. When driving the antenna via this cabling, our pulser was capable of sustaining 1200 A pulses at a rate of 30 per second up to a minute. In this way, bursts of pulses could be delivered in synch with the pendulum period in order to build up any motion. However, when using a laser beam passing through a lens attached to the antenna to amplify linear displacement by a factor of at least 25, no correlated motion of the beam spot could be detected on a distant wall. We conclude, in agreement with the momentum theorem of classical electromagnetic theory, that any thrust produced is far below practically useful levels. Hence, within classical electrodynamics, there is little hope of detecting any low level motion that cannot be explained by interactions with surrounding structural steel and the Earth's magnetic field.

  2. Experimental Setup for the Investigation of Superconducting Persistent Current

    Science.gov (United States)

    2015-09-01

    NOTES 14. ABSTRACT We report on a recent experimental setup for the investigation of the relaxation rate of the persistent current in an assembly of...at cryo-temperatures in magnetic field at time scale of seconds to hours. 15. SUBJECT TERMS persistent current, 2G HTS, coated conductor, relaxation ... activation . One unknown aspect is the variation of the coils’ position with temperature from room to cryogenic. A better design of the coils assembly

  3. Experimental typography : reviewing the modernist and the current approaches

    OpenAIRE

    Makal, Eray

    1993-01-01

    Ankara : The Department of Graphic Design and Institute of Fine Arts, Bilkent Univ., 1993. Thesis (Master's) -- Bilkent University, 1993. Includes bibliographical references leaves 65-66. The intention of this study is to evaluate the experimental typography within the history of graphic design by taking in consideration of two epochs. The Modernist and The Current. Makal, Eray M.S.

  4. Halo current diagnostic system of experimental advanced superconducting tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Chen, D. L.; Shen, B.; Sun, Y.; Qian, J. P., E-mail: jpqian@ipp.ac.cn; Wang, Y.; Xiao, B. J. [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei 230031 (China); Granetz, R. S. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States)

    2015-10-15

    The design, calibration, and installation of disruption halo current sensors for the Experimental Advanced Superconducting Tokamak are described in this article. All the sensors are Rogowski coils that surround conducting structures, and all the signals are analog integrated. Coils with two different cross-section sizes have been fabricated, and their mutual inductances are calibrated. Sensors have been installed to measure halo currents in several different parts of both the upper divertor (tungsten) and lower divertor (graphite) at several toroidal locations. Initial measurements from disruptions show that the halo current diagnostics are working well.

  5. Halo current diagnostic system of experimental advanced superconducting tokamak

    Science.gov (United States)

    Chen, D. L.; Shen, B.; Granetz, R. S.; Sun, Y.; Qian, J. P.; Wang, Y.; Xiao, B. J.

    2015-10-01

    The design, calibration, and installation of disruption halo current sensors for the Experimental Advanced Superconducting Tokamak are described in this article. All the sensors are Rogowski coils that surround conducting structures, and all the signals are analog integrated. Coils with two different cross-section sizes have been fabricated, and their mutual inductances are calibrated. Sensors have been installed to measure halo currents in several different parts of both the upper divertor (tungsten) and lower divertor (graphite) at several toroidal locations. Initial measurements from disruptions show that the halo current diagnostics are working well.

  6. Adaptive structures - Test hardware and experimental results

    Science.gov (United States)

    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.

  7. Smart Demand for Frequency Regulation: Experimental Results

    DEFF Research Database (Denmark)

    Douglass, Philip James; Garcia-Valle, Rodrigo; Nyeng, Preben

    2013-01-01

    As renewable energy sources increase their penetration, the traditional providers of frequency regulation service, fossil fueled thermal power plants, will be displaced, motivating the search for novel providers such as demandside resources. This paper presents the results of field experiments......, industrial pump loads and relay-controlled loads were tested as DFCR. The tests show that a population of refrigerators was able to deliver frequency reserves approximately equal to their average power consumption. Electric space heaters were able to provide frequency reserves of over 90% their maximum power...

  8. Charmonium physics with heavy ions: experimental results

    CERN Document Server

    Scomparin, E

    2016-01-01

    Thirty years ago, the suppression of charmonium production in heavy-ion collisions was first proposed as an unambiguous signature for the formation of a Quark-Gluon Plasma. Since then, experiments at fixed-target accelerators (SPS) and hadronic colliders (RHIC, LHC) have investigated this observable and discovered a wide range of effects, that have been related to the original proposal but at the same time have also prompted a strong development in the underlying theory concepts. In this contribution, I will review the main achievements of this field, with emphasis on recent results obtained by LHC experiments.

  9. Experimental Results on Chiral Magnetic and Vortical Effects

    Directory of Open Access Journals (Sweden)

    Gang Wang

    2017-01-01

    Full Text Available 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. 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 needed to eliminate the existing uncertainties in the interpretation of the data.

  10. Experimental Gravity Currents Propagating Downslope Over A Synthetic Topography

    Science.gov (United States)

    Burgos Cuevas, Andrea; Ruiz-Angulo, Angel; Palacios-Morales, Carlos

    2016-11-01

    Lock-release gravity currents are studied experimentally in order to investigate their dynamics and the mixing process between them and the ambient fluid. We produced these currents in a laboratory tank and allow them to propagate downslope first in a flat slope and then in a rough one with a synthetic topography. This topography is similar to the one of a side of a mountain near mexico's valley. Our aim is to investigate the dynamics of gravity currents as similar as possible to the mountain breezes that can develop around this valley. To the best of our knowledge, there are few experimental investigations that take into account the roughness of the slope. For each experiment, we obtain the instantaneous velocity fields using the standard piv technique. From the velocity fields, we estimate the entrainment coefficient time series. We found that this coefficient depends on the roughness of the surface where the current propagates. Besides, pressure time series were obtained in synthetic stations along the rough profile. These series showed a very clear signal of the gravity current propagating along the slope.

  11. Experimental simulation of gravity currents in erodible bed

    Science.gov (United States)

    Bateman, A.; La Roca, M.; Medina, V.

    2009-04-01

    Gravity currents are commonly met in nature, when a flow of denser fluid moves into a less dense one. A typical example of a gravity current is given by the sea water which flows into the bottom of a river during the summer, in correspondence of the estuary, when the river's discharge attains low values. In this case, dangerous consequences can occur, because of the polluting of the aquifer caused by the salty water. Density currents also occurs in lakes and reservoirs, because of a change in temperature or because a flood, both can produce some environmental impacts that are of interest to the local water Agency of the different countries. Of particular relevance is also the interaction of the gravity current with the movement of the sediments from the bottom of the bed. The international state of the art is particularly concerned with experimental and numerical investigation on gravity currents on fixed and porous bed [1-2-3], while, to the authors' knowledge, the interaction of a gravity current with an erodible bed is still an open field of investigation. In this paper experiments concerning with the propagation of a gravity current over fixed and erodible bed are presented. The experiments, conducted at the laboratory of Hydraulics of the Universitat Politecnica de Catalunya (actually in the Prof. Bateman's blue room), were concerned with a transparent tank 2 m long, 0.2 m wide and 0.3 m deep, partly filled with salty water and partly with fresh water, up to a depth of 0.28 m. The salty water, whose density was in the range 1050John E. Simpson. Gravity Currents [3] J.J. Monaghan, R.A.F. Cas, A.M. Kos, M. Hallworth, Gravity currents descending a ramp in a stratified tank, The Journal of Fluid Mechanics, Vol. 379, 1999

  12. Experimental results on quantum chromo dynamics: what is next?

    CERN Document Server

    De Roeck, Albert

    2013-01-01

    This review gives a flavour of experimental quantum chromo dynamics (QCD) results obtained at the Large Hadron Collider (LHC) during the first run period in the years 2010–2012. The results cover selected aspects of soft low-pT phenomena, typically described by phenomenological models, as well as high-pT processes which can be studied theoretically with perturbative techniques. In general the phenomenological models required tuning to describe the data in the new energy region of 7–8 TeV, while perturbative QCD (pQCD) is found to work generally quite well for most of the phase space currently studied. The strong force will remain a main topic of research at colliders such as the LHC also in future, with the large data samples allowing for more detailed studies and in particular when the next energy level of 13–14 TeV will be reached.

  13. SUSY effects in Rb: Revisited under current experimental constraints

    Science.gov (United States)

    Su, Wei; Yang, Jin Min

    2016-06-01

    In this note we revisit the SUSY effects in Rb under current experimental constraints including the LHC Higgs data, the B-physics measurements, the dark matter relic density and direct detection limits, as well as the precision electroweak data. We first perform a scan to figure out the currently allowed parameter space and then display the SUSY effects in Rb. We find that although the SUSY parameter space has been severely restrained by current experimental data, both the general MSSM and the natural-SUSY scenario can still alter Rb with a magnitude sizable enough to be observed at future Z-factories (ILC, CEPC, FCC-ee, Super Z-factory) which produce 109-1012Z-bosons. To be specific, assuming a precise measurement δRb = 2.0 ×10-5 at FCC-ee, we can probe a right-handed stop up to 530 GeV through chargino-stop loops, probe a sbottom to 850 GeV through neutralino-sbottom loops and a charged Higgs to 770 GeV through the Higgs-top quark loops for a large tan ⁡ β. The full one-loop SUSY correction to Rb can reach 1 ×10-4 in natural SUSY and 2 ×10-4 in the general MSSM.

  14. Integrated radar-camera security system: experimental results

    Science.gov (United States)

    Zyczkowski, M.; Palka, N.; Trzcinski, T.; Dulski, R.; Kastek, M.; Trzaskawka, P.

    2011-06-01

    The nature of the recent military conflicts and terrorist attacks along with the necessity to protect bases, convoys and patrols have made a serious impact on the development of more effective security systems. Current widely-used perimeter protection systems with zone sensors will soon be replaced with multi-sensor systems. Multi-sensor systems can utilize day/night cameras, IR uncooled thermal cameras, and millimeter-wave radars which detect radiation reflected from targets. Ranges of detection, recognition and identification for all targets depend on the parameters of the sensors used and of the observed scene itself. In this paper two essential issues connected with multispectral systems are described. We will focus on describing the autonomous method of the system regarding object detection, tracking, identification, localization and alarm notifications. We will also present the possibility of configuring the system as a stationary, mobile or portable device as in our experimental results.

  15. Multi-stage apodized pupil Lyot coronagraph experimental results

    Science.gov (United States)

    Abe, L.; Venet, M.; Enya, K.; Kataza, H.; Nakagawa, T.; Tamura, M.

    2008-07-01

    Prolate (Pupil) Apodized Lyot Coronagraphs (PPALC) are known to offer optimal performances for a Lyot-type Coronagraph configuration, i.e. with an opaque occulting focal mask. One additional benefit of PPALC is its possible use in a multi-stage configuration. In theory, the coronagraphic performance can be QN, where Q is the energy rejection factor of one stage (the first one), and N the number of stages. Several ground-based telescopes are considering PPALC as an option for their high-contrast instrumentation (e.g. Gemini/GPI, EELT/EPICS, Subaru HiCIAO). Although the PPALC suffers from several limitations, several works are currently focused on fabricating entrance pupil apodizers and trying to find ways to overcome chromatism issues. In this work, we present the first experimental results from Multi-Stage PPALC (MS-PPALC) that was done in the context of the Japanese space telescope SPICA coronagraph project. Our entrance pupil apodizers use small diameter High Energy Beam Sensitive glass (HEBS-glass) from Canyon Materials Inc. The current results show modest coronagraphic performance due to uncompensated phase aberrations inherent to HEBS-glass material. In addition, and due to these uncompensated phase aberrations, the present optical configuration is an altered version of the originally planned set-up. However, we can demonstrate the validity the MS-PPALC concept and compare it to numerical simulations.

  16. Current transformers with nanocrystalline alloy toroidal core: analytical, computational and experimental studies

    Directory of Open Access Journals (Sweden)

    Benedito Antonio Luciano

    2012-10-01

    Full Text Available In this paper are presented theoretical analysis and experimental results concerning the performance of toroidal cores used in current transformers. For most problems concerning transformers design, analytical methods are useful, but numerical methods provide a better understanding of the transformers electromagnetic behaviour. Numerical field solutions may be used to determine the electrical equivalent circuit parameters of toroidal core current transformers. Since the exciting current of current transformers alters the ratio and phase angle of primary and secondary currents, it is made as small as possible though the use of high permeability and low loss magnetic material in the construction of the core. According to experimental results presented in this work, in comparison with others soft magnetic materials, nanocrystalline alloys appear as the best material to be used in toroidal core for current transformers.

  17. Experimental Study on Current Decay Characteristics of Persistent Current HTS Magnet by Alternating Magnetic Field

    Science.gov (United States)

    Park, Young Gun; Lee, Chang Young; Hwang, Young Jin; Lee, Woo Seung; Lee, Jiho; Jo, Hyun Chul; Chung, Yoon Do; Ko, Tae Kuk

    This paper deals with a current decay characteristics of a high temperature superconducting (HTS) magnet operated in persistent current mode (PCM). In superconducting synchronous machine applications such as linear synchronous motor (LSM), the superconducting coil is designed to operate in the PCM to obtain steady magnetic field with DC transport current. This superconducting magnet operates on a direct current, but it can be exposed to alternating magnetic field due to the armature winding. When the magnet is subjected to an external time-varying magnetic field, it is possible to result in a decay of the current in PCM system due to AC loss. In this research, a PCM system with armature coil which generates time-varying magnetic field was fabricated to verify current decay characteristics by external alternating magnetic field. The current decay rate was measured by using a hall sensor as functions of amplitude and frequency of armature coil.

  18. Experimental study of yttrium barium copper oxide superconducting tape’s critical current under twisting moment

    Indian Academy of Sciences (India)

    Ziauddin Khan; Ananya Kundu; Subrata Pradhan

    2013-10-01

    Critical current (c) characteristics of 2G YBCO superconducting tape under the influence of twisting moment was experimentally investigated at varying current ramp rates in the self-field. Under a uniform twist, the degradation in the current-carrying capacity of YBCO tape up to 30% was observed at 77 K. The degradation is largely attributed to the shear stress and torsional shear strain resulting from the twisting. The superconductor to resistive transition index, , is also found to behave in an identical manner with increase in the twisting. Finite element analysis (FEA) of the tape in the experimental configuration with twisting moment being applied on to it has been carried out in COMSOL. The torsional strain calculated analytically as per the experimental configuration matches closely with that of FEA results, which shows that the critical current degradation is a function of strain.

  19. Westinghouse accident tolerant fuel program. Current results and future plans

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Sumit; Xu, Peng; Lahoda, Edward; Hallstadius, Lars; Boylan, Frank [Westinghouse Electric Company LLC, Hopkins, SC (United States)

    2016-07-15

    This paper discusses the current status, results from initial tests, as well as the future direction of the Westinghouse's Accident Tolerant Fuel (ATF) program. The current preliminary testing is addressed that is being performed on these samples at the Massachusetts Institute of Technology (MIT) test reactor, initial results from these tests, as well as the technical learning from these test results. In the Westinghouse ATF approach, higher density pellets play a significant role in the development of an integrated fuel system.

  20. The impact of triggering mechanism on flow dynamics and depositional geometry: results from an experimental study of non-conservative density currents; Influencia do mecanismo de iniciacao na dinamica dos fluxos e na geometria dos depositos gerados: observacoes obtidas a partir de estudo experimental de correntes de densidade nao-conservativas

    Energy Technology Data Exchange (ETDEWEB)

    Manica, Rafael [Rio Grande do Sul Univ., Porto Alegre (Brazil). Inst. de Pesquisas Hidraulicas. Nucleo de Estudos de Correntes de Densidade]. E-mail: rmanica@portoweb.com.br; Del Rey, Antonio Cosme; Maestri, Rogerio Dornelles; Borges, Ana Luiza de Oliveira; Viana, Adriano Roessler

    2005-05-01

    This study presents 28 physical simulations of non-conservative density currents used to evaluate their depositional patterns. Two different triggering mechanisms were used: lock gate and fluid injection. The impact of specific gravity, material type and grain size on the mixture were also checked. Dynamic and geometric features, such as head velocity and head/body height, were recorded. Results show flow velocity increase as concentration grows; deposition volumes present a general tendency to exponential decline with distance; the grain size range of the deposits decreases towards the distal portion of the channel. The results obtained have showed the efficiency of physical modeling in the study of turbidites in allowing correlations to be defined between currents and deposition patterns. (author)

  1. ITER (International Thermonuclear Experimental Reactor) current drive and heating physics

    Energy Technology Data Exchange (ETDEWEB)

    Nevins, W.M.; Lindquist, W. (Lawrence Livermore National Lab., CA (USA)); Fujisawa, N.; Kimura, H. (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan)); Hopman, H.; Rebuffi, L.; Wegrowe, J.G. (Max-Planck-Institut fuer Plasmaphysik, Garching (Germany, F.R.). NET Design Team); Parail, V.; Vdovin, V. (Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Moscow (USSR). Inst. Atomnoj Ehn

    1990-01-01

    The ITER Current Drive and Heating (CD H) systems are required for: Ionization and current initiation; Non-inductive current ramp-up assist; Heating of the plasma; Steady-state operation with full non-inductive current drive; Current profile control; and Burn control by modulation of the auxiliary power. Steady-state current drive is the most demanding requirement, so this has driven the choice of the ITER current drive and heating systems.

  2. Comprehensive Evaluation of Algal Biofuel Production: Experimental and Target Results

    Directory of Open Access Journals (Sweden)

    Colin M. Beal

    2012-06-01

    Full Text Available Worldwide, algal biofuel research and development efforts have focused on increasing the competitiveness of algal biofuels by increasing the energy and financial return on investments, reducing water intensity and resource requirements, and increasing algal productivity. In this study, analyses are presented in each of these areas—costs, resource needs, and productivity—for two cases: (1 an Experimental Case, using mostly measured data for a lab-scale system, and (2 a theorized Highly Productive Case that represents an optimized commercial-scale production system, albeit one that relies on full-price water, nutrients, and carbon dioxide. For both cases, the analysis described herein concludes that the energy and financial return on investments are less than 1, the water intensity is greater than that for conventional fuels, and the amounts of required resources at a meaningful scale of production amount to significant fractions of current consumption (e.g., nitrogen. The analysis and presentation of results highlight critical areas for advancement and innovation that must occur for sustainable and profitable algal biofuel production can occur at a scale that yields significant petroleum displacement. To this end, targets for energy consumption, production cost, water consumption, and nutrient consumption are presented that would promote sustainable algal biofuel production. Furthermore, this work demonstrates a procedure and method by which subsequent advances in technology and biotechnology can be framed to track progress.

  3. Performance of current measurement system in poloidal field power supply for Experimental Advanced Superconducting Tokamak

    Science.gov (United States)

    Liu, D. M.; Li, J.; Wan, B. N.; Lu, Z.; Wang, L. S.; Jiang, L.; Lu, C. H.; Huang, J.

    2016-11-01

    As one of the core subsystems of the Experimental Advanced Superconducting Tokamak (EAST), the poloidal field power system supplies energy to EAST's superconducting coils. To measure the converter current in the poloidal field power system, a current measurement system has been designed. The proposed measurement system is composed of a Rogowski coil and a newly designed integrator. The results of the resistor-inductor-capacitor discharge test and the converter equal current test show that the current measurement system provides good reliability and stability, and the maximum error of the proposed system is less than 1%.

  4. Summary of recent experimental results on strangeness production

    CERN Document Server

    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 {\\it 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.

  5. Summary of recent experimental results on strangeness production

    Science.gov (United States)

    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.

  6. Nonlinear random vibration experimental results and research needs

    Science.gov (United States)

    Ibrahim, R. A.

    Experimental investigations of random excitation of dynamic systems are valuable but scarce. They are particularly important for nonlinear random vibration, since different approaches can lead to different results for the same problem. They are also useful in providing physical insight into a number of complex dynamic phenomena. The scarcity of random vibration testing is mainly due to a number of difficulties and errors encountered in generating the correct random excitation, and data acquisition. The purpose of this review article is to assess the recent experimental results reported in the literature by the author and others. An attempt will be made to correlate the experimental measurements qualitatively with those predicted analytically. In most cases, no quantitative comparisons have been made. New research directions based on recent analytical and experimental developments in the theory of nonlinear random vibration will also be outlined.

  7. Experimental Verification of Current Shear Design Equations for HSRC Beams

    Directory of Open Access Journals (Sweden)

    Attaullah Shah

    2012-07-01

    Full Text Available Experimental research on the shear capacity of HSRC (High Strength Reinforced Concrete beams is relatively very limited as compared to the NSRC (Normal Strength Reinforced Concrete beams. Most of the Building Codes determine the shear strength of HSRC with the help of empirical equations based on experimental work of NSRC beams and hence these equations are generally regarded as un-conservative for HSRC beams particularly at low level of longitudinal reinforcement. In this paper, 42 beams have been tested in two sets, such that in 21 beams no transverse reinforcement has been used, whereas in the remaining 21 beams, minimum transverse reinforcement has been used as per ACI-318 (American Concrete Institute provisions. Two values of compressive strength 52 and 61 MPa, three values of longitudinal steel ratio and seven values of shear span to depth ratio have been have been used. The beams were tested under concentrated load at the mid span. The results are compared with the equations proposed by different international building codes like ACI, AASHTO LRFD, EC (Euro Code, Canadian Code and Japanese Code for shear strength of HSRC beams.From comparison, it has been observed that some codes are less conservative for shear design of HSRC beams and further research is required to rationalize these equations.

  8. Experimental study of the Timoshenko beam theory predictions: Further results

    Science.gov (United States)

    Monsivais, G.; Díaz-de-Anda, A.; Flores, J.; Gutiérrez, L.; Morales, A.

    2016-08-01

    In a previous paper (2012) we presented experimental results proving that the critical frequency fC predicted by Timoshenko beam theory indeed exists. We also showed that for frequencies f smaller than fC the spectrum is formed by almost equally spaced levels whereas for f >fC the spectrum consists of pairs of eigenvalues very close to each other as predicted by numerical solutions of Timoshenko's equation: we shall refer to them as Timoshenko doublets. In this work we measure for the first time experimental dispersion relations. For this purpose it was necessary to obtain normal-mode amplitudes with a high precision, which was done with a new experimental setup developed by us. We found that experimental dispersion relations coincide very well with theoretical predictions. Furthermore, we provide an explanation of Timoshenko doublets.

  9. Experimental observations of stray current effects on steel fibres embedded in mortar

    DEFF Research Database (Denmark)

    Solgaard, A.O.S.; Carsana, M.; Geiker, M.R.;

    2013-01-01

    It is known that stray direct current can cause corrosive damage over time to bar reinforced concrete, but knowledge on the consequences to steel fibre reinforced concrete is limited. This paper presents analyses and corresponding results from an experimental program (parametric study) investigat...

  10. The first experimental results on laser ion loading into superconducting ECR ion source at RIKEN

    CERN Document Server

    Arzumanyan, G M; Shirkov, G D; Yano, Y

    2002-01-01

    The first experimental results on ions and neutrals injection by means of laser ablation from metal targets into the RIKEN 18 GHz superconducting electron cyclotron resonance ion source (SC ECRIS) are presented. Pulsed aluminium ion currents up to Al sup 8 sup + were generated in the source. The difference in pulse shapes of various charge states of the extracted ion currents is registered

  11. Wall conditioning for ITER: Current experimental and modeling activities

    Energy Technology Data Exchange (ETDEWEB)

    Douai, D., E-mail: david.douai@cea.fr [CEA, IRFM, Association Euratom-CEA, 13108 St. Paul lez Durance (France); Kogut, D. [CEA, IRFM, Association Euratom-CEA, 13108 St. Paul lez Durance (France); Wauters, T. [LPP-ERM/KMS, Association Belgian State, 1000 Brussels (Belgium); Brezinsek, S. [FZJ, Institut für Energie- und Klimaforschung Plasmaphysik, 52441 Jülich (Germany); Hagelaar, G.J.M. [Laboratoire Plasma et Conversion d’Energie, UMR5213, Toulouse (France); Hong, S.H. [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Lomas, P.J. [CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Lyssoivan, A. [LPP-ERM/KMS, Association Belgian State, 1000 Brussels (Belgium); Nunes, I. [Associação EURATOM-IST, Instituto de Plasmas e Fusão Nuclear, 1049-001 Lisboa (Portugal); Pitts, R.A. [ITER International Organization, F-13067 St. Paul lez Durance (France); Rohde, V. [Max-Planck-Institut für Plasmaphysik, 85748 Garching (Germany); Vries, P.C. de [ITER International Organization, F-13067 St. Paul lez Durance (France)

    2015-08-15

    Wall conditioning will be required in ITER to control fuel and impurity recycling, as well as tritium (T) inventory. Analysis of conditioning cycle on the JET, with its ITER-Like Wall is presented, evidencing reduced need for wall cleaning in ITER compared to JET–CFC. Using a novel 2D multi-fluid model, current density during Glow Discharge Conditioning (GDC) on the in-vessel plasma-facing components (PFC) of ITER is predicted to approach the simple expectation of total anode current divided by wall surface area. Baking of the divertor to 350 °C should desorb the majority of the co-deposited T. ITER foresees the use of low temperature plasma based techniques compatible with the permanent toroidal magnetic field, such as Ion (ICWC) or Electron Cyclotron Wall Conditioning (ECWC), for tritium removal between ITER plasma pulses. Extrapolation of JET ICWC results to ITER indicates removal comparable to estimated T-retention in nominal ITER D:T shots, whereas GDC may be unattractive for that purpose.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Experimental study of blockage of monochromatic waves by counter currents

    NARCIS (Netherlands)

    Suastika, I.K.

    1999-01-01

    Blockage of waves by a current can occur if waves are propagating on a spatially varying opposing current in which the velocity is increasing in the wave propagation direction. The ongoing waves become shorter and steeper while they are propagating against the current. Blocking occurs at the

  14. Experimental natural circulation circuit - preliminaries results; Circuito experimental de circulacao natural - resultados experimentais preliminares

    Energy Technology Data Exchange (ETDEWEB)

    Faccini, Jose Luiz H.; Botelho, David A.; Soares, Milton; Coutinho, Jorge A.; Freitas, Sergio Carlos [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil). E-mail: faccini@cnen.gov.br

    2000-07-01

    These are the preliminaries results of the tests carried out at experimental natural circulation system of IEN/CNEN. The experimental system is a reduced scale similar model in power, pressure, and length of a passive residual heat removal prototype system. It enables studies of natural circulation phenomena in an advanced PWR. The experimental results refer to the steps of data acquisition system calibration, power control system calibration, and single-phase operational tests. The results of single-phase tests show temperature in time measured by the thermocouples placed along the natural circulation system. It is also presented a brief commentary on the experimental results, based on theory and preliminary computational simulations. (author)

  15. Design and experimental results for the S809 airfoil

    Energy Technology Data Exchange (ETDEWEB)

    Somers, D M [Airfoils, Inc., State College, PA (United States)

    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.

  16. Experimental Study on Current-Driven Domain Wall Motion

    Science.gov (United States)

    Ono, T.; Yamaguchi, A.; Tanigawa, H.; Yano, K.; Kasai, S.

    2006-06-01

    Current-driven domain wall (DW) motion for a well-defined single DW in a micro-fabricated magnetic wire with submicron width was investigated by real-space observation with magnetic force microscopy. Magnetic force microscopy visualizes that a single DW introduced in a wire is displaced back and forth by positive and negative pulsed-current, respectively. Effect of the Joule heating, reduction of the threshold current density by shape control, and magnetic ratchet effect are also presented.

  17. A Comparison of Experimental and Theoretical Results for Magnetic Bearings

    Science.gov (United States)

    Hibbs, Robert I., Jr.; Scharrer, Joseph K.; Galvin, Bonnie A.; Galvin, Mark W.

    2000-01-01

    A comprehensive program was undertaken to experimentally characterize the static and dynamic characteristics of a heteropolar magnetic bearing and to develop nonlinear theoretical models capable of accurately predicting magnetic bearing performance. This paper presents the results for the static characteristics of the magnetic bearing and a comparison with the predictions from the analytical model. The results indicate that the nonlinear theoretical model can accurately predict the static characteristics of the magnetic bearing.

  18. Experimental study of the dynamics of a thin current sheet

    Science.gov (United States)

    Gekelman, W.; DeHaas, T.; Van Compernolle, B.; Daughton, W.; Pribyl, P.; Vincena, S.; Hong, D.

    2016-05-01

    Many plasmas in natural settings or in laboratory experiments carry currents. In magnetized plasmas the currents can be narrow field-aligned filaments as small as the electron inertial length ≤ft(\\tfrac{c}{{ω }pe}\\right) in the transverse dimension or fill the entire plasma column. Currents can take the form of sheets, again with the transverse dimension the narrow one. Are laminar sheets of electric current in a magnetized plasma stable? This became an important issue in the 1960s when current-carrying plasmas became key in the quest for thermonuclear fusion. The subject is still under study today. The conditions necessary for the onset for tearing are known, the key issue is that of the final state. Is there a final state? One possibility is a collection of stable tubes of current. On the other hand, is the interaction between the current filaments which are the byproduct endless, or does it go on to become chaotic? The subject of three-dimensional current systems is intriguing, rich in a variety of phenomena on multiple scale sizes and frequencies, and relevant to fusion studies, solar physics, space plasmas and astrophysical phenomena. In this study a long (δz = 11 m) and narrow (δx = 1 cm, δy = 20 cm) current sheet is generated in a background magnetoplasma capable of supporting Alfvén waves. The current is observed to rapidly tear into a series of magnetic islands when viewed in a cross-sectional plane, but they are in essence three-dimensional flux ropes. At the onset of the current, magnetic field line reconnection is observed between the flux ropes. The sheet on the whole is kink-unstable, and after kinking exhibits large-scale, low-frequency (f ≪ f ci ) rotation about the background field with an amplitude that grows with distance from the source of the current. Three-dimensional data of the magnetic and electric fields is acquired throughout the duration of the experiment and the parallel resistivity is derived from it. The parallel

  19. Correlates of experimentation with smoking and current cigarette consumption among adolescents

    Directory of Open Access Journals (Sweden)

    Amanda Gimenes Bonilha

    2014-12-01

    Full Text Available OBJECTIVE: The aim of this study was to analyze social characteristics and stress as correlates of cigarette smoking in adolescence. The main intent was to identify elements that distinguish adolescents who had experimented with smoking and did not progress to regular smoking from those who became current smokers. METHODS: Students at 10 high schools in the city of Ribeirão Preto, Brazil, completed a questionnaire based on an instrument employed in a similar large-scale study. The students were classified as never-smokers or experimenters. The experimenters were subcategorized as having become current smokers or nonprogressors. Analyses were performed using adjusted logistic models. RESULTS: A total of 2,014 students (mean age, 16.2 ± 1.1 years; females, 53% completed the questionnaire. We categorized 1,283 students (63.7% as never-smokers, 244 (12.1% as current smokers, and 487 (24.2% as nonprogressors. We found that experimentation with smoking was associated with being held back a grade in school (OR = 1.80, alcohol intake (low/occasional, OR = 8.92; high/regular, OR = 2.64, illicit drug use (OR = 9.32, having a sibling or cousin who smokes (OR = 1.39, having a friend who smokes (OR = 2.08, and high levels of stress (in females only, OR = 1.32. Factors associated with an increased risk of transitioning from experimenter to current smoker were alcohol intake (low/occasional, OR = 3.28; high/regular, OR = 2.16, illicit drug use (OR = 3.61, and having a friend who smokes (OR = 7.20. CONCLUSIONS: Current smoking was associated with a profile of socioeconomic correlates different from that associated with experimentation only. Our data (showing that current smoking was associated with having a friend who smokes, alcohol intake, and illicit drug use suggest the need for comprehensive approaches to discourage substance use during adolescence.

  20. Feedback control of a cupola - concepts and experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Moore, K.L. [Idaho State Univ., Pocatello, ID (United States); Abdelrahman, M.A. [Tenn. Technological Univ., Cookeville, TN (United States); Larsen, E.; Clark, D. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States); King, P. [US Dept. of Energy Albany Research Center, Albany, OR (United States)

    1998-10-01

    In this paper we present some final results from a research project focused on introducing automatic control to the operation of cupola iron furnaces. The main aim of this research is to improve the operational efficiency and performance of the cupola furnace, an important foundry process used to melt iron. Previous papers have described the development of appropriate control system architectures for the cupola. These results are summarized. Then we describe the experimental results obtained with the U.S. Department of Energy Albany Research Center`s research cupola. First, experimental data is used to calibrate the model, which is taken as a first-order multivariable system with time delay. Then relative gain analysis is used to select loop pairings to be used in a multi-loop controller. The resulting controller pairs meltrate with blast volume, iron temperature with oxygen addition, and carbon composition with percent coke. Special (nonlinear) filters are used to compute meltrate from actual scale readings of the amount of iron produced and to smooth the temperature measurement. The temperature and meltrate loops use single-loop PI control. The composition loop uses a Smith predictor to discount the deadtime associated with mass transport through the furnace. Experimental results validate the conceptual controller design and provide proof-of-concept of the idea of controlling a foundry cupola. Future research directions are discussed, including the concept of an integrated, intelligent industrial process controller, or I{sup 3}PC.

  1. As it happens: current directions in experimental evolution.

    Science.gov (United States)

    Bataillon, Thomas; Joyce, Paul; Sniegowski, Paul

    2013-02-23

    Recent decades have seen a significant rise in studies in which evolution is observed and analysed directly-as it happens-under replicated, controlled conditions. Such 'experimental evolution' approaches offer a degree of resolution of evolutionary processes and their underlying genetics that is difficult or even impossible to achieve in more traditional comparative and retrospective analyses. In principle, experimental populations can be monitored for phenotypic and genetic changes with any desired level of replication and measurement precision, facilitating progress on fundamental and previously unresolved questions in evolutionary biology. Here, we summarize 10 invited papers in which experimental evolution is making significant progress on a variety of fundamental questions. We conclude by briefly considering future directions in this very active field of research, emphasizing the importance of quantitative tests of theories and the emerging role of genome-wide re-sequencing.

  2. Experimental and theoretical investigations on the singularity of the intensity factor of the current in high temperature superconductors

    Science.gov (United States)

    Zhang, Xingyi; Huang, Yi; Zhou, Jun; Zhou, Youhe

    2013-08-01

    This paper presents experimental and analytical investigations into the distribution of current around a through-edge crack located in an infinitely long cylindrical high temperature superconductor (HTS) on the basis of the Bean model. Current distributions around the crack in the HTS without deformation are obtained by a simple conformal mapping. It is shown that the current is singular at the tip of the crack. An intensity factor of the current is introduced to characterize the singularity, the order of which is equal to -1. Additionally, an experimental verification according to the trapped field distributions around the crack is carried out, and the experimental results show little difference with the theoretical analysis.

  3. First experimental results on CMOS Integrated Nickel Electroplated Resonators

    DEFF Research Database (Denmark)

    Yalcinkaya, Arda Deniz; Hansen, Ole

    2004-01-01

    This paper presents experimental results on MEMS metallic add-on post-fabrication effects on complementary metal oxide semiconductor (CMOS) transistors. Two versions of add-on processing, that use either e-beam evaporation or magnetron sputtering, are compared through investigation of the electri......This paper presents experimental results on MEMS metallic add-on post-fabrication effects on complementary metal oxide semiconductor (CMOS) transistors. Two versions of add-on processing, that use either e-beam evaporation or magnetron sputtering, are compared through investigation...... of the electrical parameters of n-channel and p-channel transistors. The magnetron sputtering technique is shown to be compatible with standard CMOS electronics without any restriction of the metal types and annealing requirements....

  4. Simulation of ATPG Neural Network and Its Experimental Results

    Institute of Scientific and Technical Information of China (English)

    张中

    1995-01-01

    This paper first establishes a neural network model for logic circuits from the truth tableby using linear equations theory,presents a kind of ATPG neural network model,and investigates energy local minima for the network.And then,it proposes the corresponding techniques to reduce the number of energy local minima as well as some approaches to escaping from local minimum of energy.Finally,two simulation systems,the binary ATPG neural network and the continuous ATPG neural network,are implemented on SUN 3/260 workstation in C language.The experimental results and their analysis and discussion are given.The preliminary experimental results show that this method is feasible and promising.

  5. Realizing life-scalable experimental pyroclastic density currents

    Science.gov (United States)

    Cronin, S. J.; Lube, G.; Breard, E.; Jones, J.; Valentine, G.; Freundt, A.; Hort, M. K.; Bursik, M. I.

    2013-12-01

    Pyroclastic Density Currents (PDCs) - the most deadly threat from volcanoes - are extremely hot, ground-hugging currents of rock fragments and gas that descend slopes at hundreds of kilometers per hour. These hostile flows are impossible to internally measure, thus volcanologists are persistently blocked in efforts to realistically forecast their internal mechanics and hazards. Attempts to fill this gap via laboratory-scale experiments continue to prove difficult, because they usually mismatch the dynamic and kinematic scaling of real-world flows by several orders of magnitude. In a multi-institutional effort, the first large-scale pyroclastic flow generator that can synthesize repeatable hot high-energy gas-particle mixture flows in safety has been commissioned in New Zealand. The final apparatus stands 15 m high, consisting of a tower/elevator system; an instrumented hopper that can hold >6000 kg (or 3.2 m3) of natural volcanic materials, which can be discharged at a range of controlled rates onto an instrumented, variably inclinable (6-25°) glass-sided chute for examining the vertical profiles of PDCs in motion. The use of rhyolitic pyroclastic material from the 1800 AD Taupo Eruption (with its natural grain-size, sorting and shape characteristics) and gas ensures natural coupling between the solids and fluid phases. PDC analogues with runout of >15 meters and flow depths of 1.5-6 meters are created by generating variably heated falling columns of natural volcanic particles (50-1300 kg/s), dispersed and aerated to controlled particle densities between 3 and 60 vol.% at the base of the elevated hopper. The descending columns rapidly generate high-velocity flows (up to 14 m/s) once impacting on the inclined channel, reproducing many features of natural flows, including segregation into dense and dilute regimes, progressive aggradational and en masse deposition of particles and the development of high internal gas-pore-pressures during flow. The PDC starting

  6. Microconfined equiviscous droplet deformation: Comparison of experimental and numerical results

    Science.gov (United States)

    Vananroye, Anja; Janssen, Pieter J. A.; Anderson, Patrick D.; Van Puyvelde, Peter; Moldenaers, Paula

    2008-01-01

    The dynamics of confined droplets in shear flow is investigated using computational and experimental techniques for a viscosity ratio of unity. Numerical calculations, using a boundary integral method (BIM) in which the Green's functions are modified to include wall effects, are quantitatively compared with the results of confined droplet experiments performed in a counter-rotating parallel plate device. For a viscosity ratio of unity, it is experimentally seen that confinement induces a sigmoidal droplet shape during shear flow. Contrary to other models, this modified BIM model is capable of predicting the correct droplet shape during startup and steady state. The model also predicts an increase in droplet deformation and more orientation toward the flow direction with increasing degree of confinement, which is all experimentally confirmed. For highly confined droplets, oscillatory behavior is seen upon startup of flow, characterized by an overshoot in droplet length followed by droplet retraction. Finally, in the case of a viscosity ratio of unity, a minor effect of confinement on the critical capillary number is observed both numerically and experimentally.

  7. Experimental results on charge fluctuations in heavy-ion collisions

    CERN Document Server

    Mishra, D K; Netrakanti, P K; Pant, L M; Mohanty, A K

    2016-01-01

    We present a subset of experimental results on charge fluctuation from the heavy-ion collisions to search for phase transition and location of critical point in the QCD phase diagram. Measurements from the heavy-ion experiments at the SPS and RHIC energies observe that total charge fluctuations increase from central to peripheral collisions. The net-charge fluctuations in terms of dynamical fluctuation measure $\

  8. Experimental results for a novel rotary active magnetic regenerator

    DEFF Research Database (Denmark)

    Engelbrecht, Kurt; Eriksen, Dan; Bahl, Christian

    2012-01-01

    in a solid refrigerant rather than the temperature change that occurs when a gas is compressed/expanded. This paper presents the general considerations for the design and construction of a high frequency rotary AMR device. Experimental results are presented at various cooling powers for a range of operating...... conditions near room temperature. The device exhibited a no-load temperature span of over 25 K and can absorb a 100 W cooling load at a 20.5 K temperature span....

  9. Experimental Results and Theoretical Developments of Muon g-2

    CERN Document Server

    Deng, H; Bennett, G W; Bousquet, B; Brown, H N; Bunce, G; Carey, R M; Cushman, P; Danby, G T; Debevec, P T; Deile, M; Dhawan, S K; Druzhinin, V P; Duong, L; Farley, F J M; Fedotovich, G V; Gray, F E; Grigoriev, D; Grosse-Perdekamp, M; Grossmann, A; Hare, M; Hertzog, D W; Huang, X; Hughes, V W; Iwasaki, M; Jungmann, Klaus; Kawall, D; Khazin, B I; Krienen, F; Kronkvist, I J; Lam, A; Larsen, R; Lee, Y Y; Logashenko, I; McNabb, R; Meng, W; Miller, J P; Morse, W M; Nikas, D; Onderwater, Gerco; Orlov, Y; Ozben; Paley, J M; Peng, Q; Polly, C C; Pretz, J; Prigl, R; zu Putlitz, Gisbert; Qian, T; Redin, S I; Rind, O; Roberts, B L; Ryskulov, N M; Semertzidis, Y K; Shagin, P; Shatunov, Yu M; Sichtermann, E P; Solodov, E; Sossong, M; Sulak, L R; Trofimov, A; Von Walter, P; Yamamoto, A

    2004-01-01

    The anomalous magnetic moments of both positive and negative muons are measured to the precision of 0.7 parts per million. Two values are in good agreement. The standard model calculations of muon g-2 are under further studies, especially the descrepancies between $e^+e^-$ and $\\tau$ data. The differences between experimental result and the standard model calculations are $2.4\\sigma$ for $e^+e^-$ data and $0.9\\sigma$ for $\\tau$ data.

  10. Experimental results on spin physics at the AGS

    Energy Technology Data Exchange (ETDEWEB)

    Makdisi, Y.I.

    1986-01-01

    The AGS ran with polarized protons towards the end of 1985 and through the first two months of 1986. This comprised commissioning periods interleaved with two runs for physics at 13.5 GeV/c with beam polarization of 50 to 60%, and 18.5 GeV/c with an average beam polarization of 40%. Later, the AGS polarized beam reached peak energy of 22 GeV/c and polarization of 46%. This article describes the various spin related experimental efforts since the VI Symposium at Marseille. These will be grouped into those using unpolarized beams and the rest are the polarized proton beam users. Afterwards the future of the program is described as extensions of current experiments in addition to other measurements that are yet to be proposed.

  11. EXPERIMENTAL INVESTIGATIONS ON DIFFUSION CHARACTERISTICS OF HIGH CONCENTRATION JETS IN ENVIRONMENTAL CURRENTS

    Institute of Scientific and Technical Information of China (English)

    张燕; 王道增; 樊靖郁

    2002-01-01

    By means of flow visualization and quantitative measurement, the diffusionpattern and concentration distribution characteristics of high concentration jets verticallydischarged into shallow moving waterbody were experimentally investigated in waterchannel. The interactions between the high concentration jets and environmental flowconditions were analysed, and the formulae of impinging point coordinate and transversespread angle are gained from data analysis. Experimental results indicate that the jets showcomplicated flow patterns and diffusion characteristics in near region, which are differentfrom common submerged jets, and spread downstream in the manner of density currents.

  12. Current experimental situation in heavy-ion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Scott, D.K.

    1978-06-01

    A detailed survey of the present experimental situation in heavy-ion physics is presented. The discussion begins by considering the simple excitation of discrete states in elastic scattering, transfer, and compound-nucleus reactions; it then turns to more drastic perturbations of the nucleus high in the continuum through fusion, fission, and deeply inelastic scattering, and concludes with the (possibly) limiting asymptotic phenomena of relativistic heavy-ion collisions. 138 figures, 5 tables, 451 references. (RWR)

  13. OIL DECONTAMINATION OF BOTTOM SEDIMENTS EXPERIMENTAL WORK RESULTS

    Directory of Open Access Journals (Sweden)

    Lushnikov Sergey V.

    2006-08-01

    Full Text Available This article presents the results of experimental work during 2004-2005 on oil decontamination of bottom sediments of Lake Schuchye, situated in the Komi Republic (Northern Russia. The cause of thecontamination were huge oil spills occurred after a series of accidental ruptures on the Harjaga-Usinsk and Vozej-Usinsk oil-pipe lines in 1994. Flotation technology was used for the cleaning of bottom sediments.157 tons of crude oil were removed during the course of 2-year experimental work from an area of 4,1 ha.The content of aliphatic and alicyclic oil hydrocarbons was reduced from 53,3 g/kg to 2,2 g/kg, on average.Hydrobiological investigations revealed that bottom sediments started to be inhabited by benthos organisms, dominantly Oligochaeta. Besides Oligochaeta, Chironomidae maggots and Bivalvia were detected. Theappearance of Macrozoobenthos organisms can serve as a bioindicator of water quality.

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

    Science.gov (United States)

    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.

  15. Experimental Results on Low Alpha Electron-Storage Rings

    Science.gov (United States)

    Robin, D.; Hama, H.; Nadji, A.

    1996-04-01

    We report on experiments performed in two synchrotron light sources, UVSOR and Super-ACO, where the momentum compaction factor is reduced in order to reduce the bunch length. By controlling the second-order momentum compaction factor, UVSOR and Super-ACO have managed to reduce the first-order momentum compaction factor by a a factor of 100. At low current the resulting bunch lengths are less than 10 ps, a factor of 10 smaller than normal. Measurements of current-dependent bunch lengthening in UVSOR are presented, and the cause of the bunch lengthening is determined to be potential-well distortion. We also show that by operating with a negative momentum compaction factor, Super-ACO has achieved shorter bunch lengthening and higher peak currents than at positive momentum compaction.

  16. Experimental manifestation of the breakpoint region in the current-voltage characteristics of intrinsic Josephson junctions

    Science.gov (United States)

    Irie, A.; Shukrinov, Yu. M.; Oya, G.

    2008-10-01

    The experimental evidence of the breakpoint on the current-voltage characteristics (IVCs) of the stacks of intrinsic Josephson junctions (IJJs) is presented. The influence of the capacitive coupling on the IVCs of Bi2Sr2CaCu2Oy IJJs has been investigated. At 4.2K, clear breakpoint region is observed on the branches in the IVCs. It is found that due to the coupling between junctions, the hysteresis observed on the IVC is small compared to that expected from the McCumber parameter. Measurements agree well with the results predicted by the capacitively coupled Josephson junction model including the diffusion current.

  17. Recent results on current profile shaping on tore supra

    Energy Technology Data Exchange (ETDEWEB)

    Becoulet, A.

    1994-12-31

    The link between the current profile and the confinement is studied, involving various regimes: high power minority ion cyclotron resonant heating, high power lower hybrid current drive, fast wave direct electron heating and current drive and pellet enhanced performance. It is shown that the electron heat diffusivity decreases when the magnetic shear increases in the confinement zone and/or when it decreases in the plasma centre. (authors). 13 refs., 6 figs.

  18. Experimental Investigation of a Direct Methanol Fuel Cell with Hilbert Fractal Current Collectors

    Directory of Open Access Journals (Sweden)

    Jing-Yi Chang

    2014-01-01

    Full Text Available The Hilbert curve is a continuous type of fractal space-filling curve. This fractal curve visits every point in a square grid with a size of 2×2, 4×4, or any other power of two. This paper presents Hilbert fractal curve application to direct methanol fuel cell (DMFC current collectors. The current collectors are carved following first, second, and third order Hilbert fractal curves. These curves give the current collectors different free open ratios and opening perimeters. We conducted an experimental investigation into DMFC performance as a function of the free open ratio and opening perimeter on the bipolar plates. Nyquist plots of the bipolar plates are made and compared using electrochemical impedance spectroscopy (EIS experiments to understand the phenomena in depth. The results obtained in this paper could be a good reference for future current collector design.

  19. Experimental Research of Harmonic Spectrum of Currents at Traction Drive with PMSM

    Directory of Open Access Journals (Sweden)

    J. Novak

    2011-06-01

    Full Text Available The paper deals with the significant results of the experimental research of current harmonic spectrum of traction drive with permanent magnet synchronous motor. The experiments were done on a special workplace with a real traction drive for wheel vehicles. Current harmonic spectrum was analyzed by a specialized device on the base of central measuring station. The knowledge of current marked subharmonic components of stator winding is the most significant finding of experiments. The frequencies of these components are given by multiples of frequency of mechanical speeds. The subharmonic components also pass to input DC current of drive. This fact is important in particular from the point of view of legislative requirements to electromagnetic compatibility of drive with railway interlocking devices.

  20. Experimental Results on Charge Fluctuations in Heavy-Ion Collisions

    Directory of Open Access Journals (Sweden)

    D. K. Mishra

    2017-01-01

    Full Text Available We present a subset of experimental results on charge fluctuation from the heavy-ion collisions to search for phase transition and location of critical point in the QCD phase diagram. Measurements from the heavy-ion experiments at the SPS and RHIC energies observe that total charge fluctuations increase from central to peripheral collisions. The net-charge fluctuations in terms of dynamical fluctuation measure ν(+-,dyn are studied as a function of collision energy (sNN and centrality of the collisions. The product of ν(+-,dyn and 〈Nch〉 shows a monotonic decrease with collision energies, which indicates that at LHC energy the fluctuations have their origin in the QGP phase. The fluctuations in terms of higher moments of net-proton, net-electric charge, and net-kaon have been measured for various sNN. Deviations are observed in both Sσ and κσ2 for net-proton multiplicity distributions from the Skellam and hadron resonance gas model for sNN<39 GeV. Higher moment results of the net-electric charge and net-kaon do not observe any significant nonmonotonic behavior as a function of collision energy. We also discuss the extraction of the freeze-out parameters using particle ratios and experimentally measured higher moments of net-charge fluctuations. The extracted freeze-out parameters from experimentally measured moments and lattice calculations are found to be in agreement with the results obtained from the fit of particle ratios to the thermal model calculations.

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

    Directory of Open Access Journals (Sweden)

    Vercelli A.

    2010-06-01

    Full Text Available 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Xin, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Belomestnykh, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Brutus, J. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Skaritka, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wu, Q. [Brookhaven National Lab. (BNL), Upton, NY (United States); Xiao, B. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    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.

  3. Test results of the 18 kA EDIPO HTS current leads

    Energy Technology Data Exchange (ETDEWEB)

    Wesche, Rainer, E-mail: rainer.wesche@psi.ch [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom - Confederation Suisse, 5232 Villigen PSI (Switzerland); Bagnasco, Maurizio; Bruzzone, Pierluigi; Felder, Roland; Guetg, Marc; Holenstein, Manuel; Jenni, Markus; March, Stephen; Roth, Felix; Vogel, Martin [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom - Confederation Suisse, 5232 Villigen PSI (Switzerland)

    2011-10-15

    For the new test facility EDIPO (European DIPOle), to be hosted by CRPP, two 18 kA HTS current leads were manufactured and successfully tested. The HTS module, made of AgMgAu/Bi-2223 tapes, is cooled only by heat conduction to the cold end, while the copper part is cooled by forced flow helium gas. The current leads were tested at low voltage up to the maximum current of 18 kA. The helium mass flow rates required for stable operation at various currents were determined. In addition to the steady state operation, the transient behavior in the case of a loss of flow was studied experimentally. The test results provide an estimate of the operational limits of the EDIPO HTS current leads.

  4. Evaluating the osseointegration of nanostructured titanium implants in animal models: Current experimental methods and perspectives (Review).

    Science.gov (United States)

    Babuska, Vaclav; Moztarzadeh, Omid; Kubikova, Tereza; Moztarzadeh, Amin; Hrusak, Daniel; Tonar, Zbynek

    2016-09-15

    The aim of this paper is to review the experimental methods currently being used to evaluate the osseointegration of nanostructured titanium implants using animal models. The material modifications are linked to the biocompatibility of various types of oral implants, such as laser-treated, acid-etched, plasma-coated, and sand-blasted surface modifications. The types of implants are reviewed according to their implantation site (endoosseous, subperiosteal, and transosseous implants). The animal species and target bones used in experimental implantology are carefully compared in terms of the ratio of compact to spongy bone. The surgical technique in animal experiments is briefly described, and all phases of the histological evaluation of osseointegration are described in detail, including harvesting tissue samples, processing undemineralized ground sections, and qualitative and quantitative histological assessment of the bone-implant interface. The results of histological staining methods used in implantology are illustrated and compared. A standardized and reproducible technique for stereological quantification of bone-implant contact is proposed and demonstrated. In conclusion, histological evaluation of the experimental osseointegration of dental implants requires careful selection of the experimental animals, bones, and implantation sites. It is also advisable to use larger animal models and older animals with a slower growth rate rather than small or growing experimental animals. Bones with a similar ratio of compact to spongy bone, such as the human maxilla and mandible, are preferred. A number of practical recommendations for the experimental procedures, harvesting of samples, tissue processing, and quantitative histological evaluations are provided.

  5. Experimental results of breakdown in "Dena" plasma focus device

    Science.gov (United States)

    Goudarzi, Shervin; Hoseinian, S. M.; Raeisdana, A.

    2014-06-01

    In spite of the intense research activities on Plasma Focus devices, the physics of the initial breakdown and surface discharge phase has not been realized completely. In this paper we have analyzed the surface discharge and initial breakdown phase in Filippov-type Plasma Focus Facility "Dena" (90 kJ, 25 kV) on the base of the current and current derivative measured signals by using Argon, Neon and Krypton as working gases at different discharge voltages and gas pressures, and the effects of working conditions (atomic weight, discharge voltage and gas pressure) on the breakdown and surface discharge phase have expressed. Also, on the base of these results, we have investigated about the relation of this phase with final pinch phase.

  6. Experimental investigation of current free double layers in helicon plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, B. B. [Department of Applied Sciences and Humanities, Dronacharya College of Engineering, Gurgaon 123506 (India); Tarey, R. D. [Department of Physics, Indian Institute of Technology, New Delhi 110016 (India); Ganguli, A. [Centre for Energy Studies, Indian Institute of Technology, New Delhi 110016 (India)

    2014-02-15

    The paper presents investigations of current free double layer (CFDL) that forms in helicon plasmas. In contrast to the other work reporting on the same subject, in the present investigations the double layer (DL) forms in a mirror-like magnetic field topology. The RF compensated Langmuir probe measurements show multiple DLs, which are in connection with, the abrupt fall of densities along with potential drop of about 24 V and 18 V. The DLs strengths (e ΔV{sub p})/(k T{sub e}) are about 9.5 and 6, and the corresponding widths are about 6 and 5 D lengths. The potential drop is nearly equal to the thermal anisotropies between the two plasma regions forming the DL, which is present in the plateau region of mirror, unlike the earlier studies on the DL formation in the region of strong gradients in the magnetic field. Also, it presents a qualitative discussion on the mechanism of DL formation.

  7. Comparison of ATHENA/RELAP results against ice experimental data

    CERN Document Server

    Moore-Richard, L

    2002-01-01

    In order to demonstrate the adequacy of the International Thermonuclear Experimental Reactor design from a safety stand point as well as investigating the behavior of two-phase flow phenomena during an ingress of coolant event, an integrated ICE test facility was constructed in Japan. The data generated from the ICE facility offers a valuable means to validate computer codes such as ATHENA /RELAP5, which is one of the codes used at the Idaho National Engineering And Environmental Laboratory (INEEL) to evaluate the safety of various fusion reactor concepts. In this paper we compared numerical results generated by the ATHENA code with corresponding test data from the ICE facility. Overall we found good agreement between the test data and the predicted results.

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

    Science.gov (United States)

    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.

  9. Computational and experimental studies of laser cutting of the current collectors for lithium-ion batteries

    Science.gov (United States)

    Lee, Dongkyoung; Patwa, Rahul; Herfurth, Hans; Mazumder, Jyotirmoy

    2012-07-01

    Sizing electrodes is an important step during Lithium-ion battery manufacturing processes since poor cut edge affects battery performance significantly and sometime leads to fire hazard. Mechanical cutting could result in a poor cut quality with defects. The cutting quality can be improved by using a laser, due to its high energy concentration, fast processing time, small heat-affected zone, and high precision. The cutting quality is highly influenced by operating parameters such as laser power and scanning speed. Thus, we studied a numerical simulation to provide a guideline for achieving clear edge quality. In order to simulate electrodes laser cutting for Lithium-Ion batteries, understanding the behavior of current collectors is crucial. This study focuses on current collectors, such as pure copper and aluminium. Numerical studies utilized a 3D self-consistent mathematical model for laser-material interaction. Observations of penetration time, depth, and threshold during laser cutting processes of current collectors are described. The model is validated experimentally by cutting current collectors and single side-coated electrodes with a single mode fiber laser. The copper laser cutting is laser intensity and interaction time dependent process. The aluminium laser cutting depends more on laser intensity than the interaction time. Numerical and experimental results show good agreement.

  10. Automation in dairy cattle milking: experimental results and considerations

    Directory of Open Access Journals (Sweden)

    Marisanna Speroni

    2010-01-01

    Full Text Available The results of two experimental programs financed to the Istituto Sperimentale per la Zootecnia are presented. The objective of the two Italian programs was the verify if automatic milking is a suitable practice for Italian dairy system. Results are summarised and compared to those obtained in other international projects. Results refer to animal behaviour, milk yield, milk quality an animal welfare. In a trial comparing cows milked with an automatic milking system and cows milked in a milking parlour, we observed that when the temperature and humidity are very high cows reduce their activity, have lower milking frequency and milk yield than in cold seasons. In comparison to milking parlour, automatic milking system did not increase milk yield which was affected significantly by season, stage of lactation, parity, season per treatment and parity per treatment. The causes of the negative results obtained by this group and by other international groups are discussed. We also presented the results obtained in four trials thereby four appetizers or flavourings were tested to improve efficiency of automatic milking system. Comparing the two milking systems, automatic milking determined a worsening of milk quality, but from these data is not possible to exclude the possibility to use automatic milking for Grana Padano and Parmigiano Reggiano-type cheeses. Animal welfare is not negatively influenced by automatic milking system, which has the potentiality to improve the control and care of cows.

  11. DoSSiER: Database of Scientific Simulation and Experimental Results

    CERN Document Server

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

    2017-01-01

    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 article, we describe the functionality and the current status of various components of DoSSiER as well as the technology choices we made.

  12. Current Trends in Nursing Informatics: Results of an International Survey.

    Science.gov (United States)

    Peltonen, Laura-Maria; Alhuwail, Dari; Ali, Samira; Badger, Martha K; Eler, Gabrielle Jacklin; Georgsson, Mattias; Islam, Tasneem; Jeon, Eunjoo; Jung, Hyunggu; Kuo, Chiu-Hsiang; Lewis, Adrienne; Pruinelli, Lisiane; Ronquillo, Charlene; Sarmiento, Raymond Francis; Sommer, Janine; Tayaben, Jude L; Topaz, Maxim

    2016-01-01

    Nursing informatics (NI) can help provide effective and safe healthcare. This study aimed to describe current research trends in NI. In the summer 2015, the IMIA-NI Students Working Group created and distributed an online international survey of the current NI trends. A total of 402 responses were submitted from 44 countries. We identified a top five NI research areas: standardized terminologies, mobile health, clinical decision support, patient safety and big data research. NI research funding was considered to be difficult to acquire by the respondents. Overall, current NI research on education, clinical practice, administration and theory is still scarce, with theory being the least common. Further research is needed to explain the impact of these trends and the needs from clinical practice.

  13. Experimental active control results from the SPICES smart structure demonstrations

    Science.gov (United States)

    Flamm, David S.; Toth, G. K.; Chou, Kenneth C.; Heck, Larry P.; Nowlin, William C.; Titterton, Paul J., Sr.

    1996-05-01

    The final demonstrations of the ARPA SPICES (Synthesis and Processing of Intelligent Cost Effective Structures) program test the control of two active vibration mounts manufactured from composites with embedded actuators and sensors. Both mount demonstrations address wide band control problems for real disturbances, one at low frequency and the other at high frequency. The control systems for both are two-level hierarchies, with an inner active damping augmentation loop and an outer vibration control loop. We first review the control design requirements for the demonstration and summarize our control design approach. Then we focus on presenting the experimental results of the final demonstrations. For the low frequency demonstration, two alternative control approaches were demonstrated, one involving finite impulse response modeling and the other state space modeling. For the high frequency demonstration only the finite impulse response modeling approach was used because of computational limitations due to the complex system dynamics.

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

    Science.gov (United States)

    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.

  15. Selected Experimental Results from Heavy-Ion Collisions at LHC

    Directory of Open Access Journals (Sweden)

    Ranbir Singh

    2013-01-01

    Full Text Available We review 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 energy sNN=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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  18. Registration of multimodal brain images: some experimental results

    Science.gov (United States)

    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.

  19. EXPERIMENTAL RESULTS OF THE NEPHELINE PHASE III STUDY

    Energy Technology Data Exchange (ETDEWEB)

    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

  20. San Juan Fracture Characterization Project: Status and current results

    Energy Technology Data Exchange (ETDEWEB)

    Majer, E.L.; Daley, T.M.; Myer, L.R.; Nihei, K.; Queen, J.; Sinton, J.; Murphy, J.; Fortuna, M.; Lynn, H.B.; Imhoff, M.A.; Wilson, R.

    2001-02-26

    The overall objectives of this report are to extend current state-of-the-art 3-D imaging to extract the optimal information for fracture quantification and to develop next generation capability in fracture imaging for true 3-D imaging of the static and dynamic fracture properties.

  1. Principle and experimental investigation of current-driven negative-inductance superconducting quantum interference device

    Science.gov (United States)

    Li, Hao; Liu, Jianshe; Zhang, Yingshan; Cai, Han; Li, Gang; Liu, Qichun; Han, Siyuan; Chen, Wei

    2017-03-01

    A negative-inductance superconducting quantum interference device (nSQUID) is an adiabatic superconducting logic device with high energy efficiency, and therefore a promising building block for large-scale low-power superconducting computing. However, the principle of the nSQUID is not that straightforward and an nSQUID driven by voltage is vulnerable to common mode noise. We investigate a single nSQUID driven by current instead of voltage, and clarify the principle of the adiabatic transition of the current-driven nSQUID between different states. The basic logic operations of the current-driven nSQUID with proper parameters are simulated by WRspice. The corresponding circuit is fabricated with a 100 A cm‑2 Nb-based lift-off process, and the experimental results at low temperature confirm the basic logic operations as a gated buffer.

  2. RESULTS OF EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF THE HERRING SALTING

    Directory of Open Access Journals (Sweden)

    M. V. Shumanova

    2015-01-01

    Full Text Available To the salting process of fish many studies are devoted, both in experimental and in theoretical terms. Study of features of fish salting in historical terms can be divided into 3 groups. One group of researchers believes that osmotic pressure has a major influence during the salting process. Another group attributed this process to the influence of molecular diffusion. The third group considers that during this process takes place both osmosis and diffusion. Determination of the main characteristics (salinity, diffusion coefficients, time of salting, etc. is a very time-consuming task. This leads to the idea of searching for innovative research methods. Current state of science, in addition to theoretical solutions points to the possibility to determine the basic characteristics of salting and applying methods associated with the interaction of ultrasound and electromagnetic radiation with matter. In our studies, we have been producing laser beam scanning of salt solution and fish meat thickness. Scattered radiation is determined by the salt concentration, diffusion coefficients, the size of the diffusing particles. This method is called a photon correlation spectroscopy. It has been applied in our work. The dependence of the scattered light intensity on the concentration of sodium chloride solution (brine has been investigated. According to diffusion coefficient a diffusion in solution to herring skin a conclusion was made that salt solution obtains fractal structure and its size was determined. Also we determined diffusion coefficients depending on the temperature in the layers. The layers are brine-leather, leather, and herring meat thickness. The process of diffusion-osmotic equilibrium revealed at temperatures of 10-12 ° C. Suggested the possibility of higher quality of fish salting at low temperatures. On the basis of the selfsimilar solution of the differential diffusion equation, a formula for calculating time salting fish was obtained

  3. Mean field approaches for $\\Xi^-$ hypernuclei and current experimental data

    CERN Document Server

    Sun, T T; Sagawa, H; Schulze, H -J; Meng, J

    2016-01-01

    Motivated by the recently observed hypernucleus (Kiso event) $^{15}_{\\Xi}$C ($^{14}$N$+\\Xi^-$), we identify the state of this system theoretically within the framework of the relativistic-mean-field and Skyrme-Hartree-Fock models. The $\\Xi N$ interactions are constructed to reproduce the two possibly observed $\\Xi^-$ removal energies, $4.38\\pm 0.25$ MeV or $1.11\\pm 0.25$ MeV. The present result is preferable to be $^{14}{\\rm N}({\\rm g.s.})+\\Xi^-(1p)$, corresponding to the latter value.

  4. EXPERIMENTAL STUDY ON BED-LOAD SEDIMENT TRANSPORT IN IRREGULAR WAVE-CURRENT COEXISTENT FIELD

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to evaluate bed-load sediment transport in an irregular wave-current coexistent field, a series of experiments were completed in laboratory with an irregularly oscillating tray, which was specially designed to simulate the irregular wave-current coexistent field. Experimental results are presented on the initial motion of sediment and the rates of transport over flat horizontal bed. Testing conditions included three interaction angles, 0°, 45°, 90° and six kinds of grain sizes. Four kinds (0.2mm, 0.46mm, 0.85mm and 1.3mm) were used for the tests of initial motion, while the other two kinds (0.38mm and 1.1mm) for the tests of transport rate. Comparisons between experimental results of initial motion and modified Shields curve indicate that the Shields curve is still valid for the case of irregular wave-current coexistent field. Analysis of flow regime shows that initial conditions fall within smooth-turbulent transitional region. The results of transport rate show us that net sediment transport rate can be expressed approximately as the function of the maximum bottom shear stress and mean shear stress. A dimensionless formula is proposed on the basis of mechanism "Waves erode sediments, tides transport sediments".

  5. Internal wave emission from baroclinic jets: experimental results

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.''

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

    Science.gov (United States)

    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. Results of experimental investigations of cobalt beta decay rate variation

    CERN Document Server

    Baurov, Yu A; Nikitin, V A; Dunin, V B; Tihomirov, V V; Sergeev, S V; Demchuk, N A

    2013-01-01

    Results of long-term investigations of variation of cobalt beta decay rate from 28.12.2010 till 08.02.2012 are presented. The scintillation spectrometer with two LaBr3 detectors is used to register of gamma-quanta with energy 1.173 and 1.332 MeV accompanying cobalt beta decay. Counting rate of each detector and their gamma-quanta coincidence are collected in successive time intervals 10 s. The statistical Kolmogorov-Smirnov method for data analysis is used. Temperature influence on experimental results is also analyzed. Deviations of beta decay counting rate from constant distribution during the days were detected in those decades: from 11.03 to 21.03 with significance level a = 0.1; from 22.04 to 02.05 with a=0.0125; from 24.06 to 04.07 with a=0.05; from 04.08 to 14.08 with a=0.05.

  10. Experimental study of the velocity of density currents in convergent and divergent channels

    Institute of Scientific and Technical Information of China (English)

    Hasan Torabi POUDEH; Samad EMAMGHOLIZADEH; Manoocher Fathi-MOGHADAM

    2014-01-01

    The head velocity of the density current in the convergent and divergent channel is a key parameter for evaluating the extent to which suspended material travels, and for determining the type and distribution of sediment in the water body. This study experimentally evaluated the effects of the reach degree of convergence and divergence on the head velocity of the density current. Experiments were conducted in the flume with 6.0 m long, 0.72 m width and 0.6 m height. The head velocity was measured at three convergent degrees (-8o;-12o;-26o), at three divergent degrees (8o; 12o; 26o) and two slopes (0.009, 0.016) for various discharges. The measured head velocity of the density current is compared with the head velocity of the density current in the constant cross section channel. Based on non-dimensional and statistical analysis, relations as linear multiple regression are offered for predicting head velocity of the density current in the convergent, divergent and constant cross section channel. Also the results of this research show that for the same slope and discharge, the head velocity of the density current in the convergent and divergent channel are greater and less than the head velocity of the constant cross section, respectively.

  11. Experimental results on V-M type pulse tube refrigerator

    Science.gov (United States)

    Dai, Wei; Matsubara, Yoichi; Kobayashi, Hisayasu

    2002-06-01

    This article mainly introduces experimental results on a new type pulse tube refrigerator named as V-M type pulse tube refrigerator. The main difference from Stirling type or G-M type pulse tube refrigerator is that thermal compressor similar to that of a V-M cryocooler is used instead of mechanical compressor. By using temperature difference between room temperature and liquid nitrogen, pressure wave with high to low pressure ratio around 1.2 is obtained. This pressure wave is used to generate cooling effect at the cold end. With a 20 K pre-cooler, this machine reaches lowest temperature 5.25 K by using helium 4 at 0.77 Hz, 19 bar charge pressure. DC flow plays an important role in our system. It not only influences the final obtainable lowest temperature, but also is used to increase cold end cool-down speed. Total volume of the V-M type pulse tube refrigerator is around 3.3 l. However, dead volume inside rotor housing occupies about 2.8 l and can be much reduced.

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

    Science.gov (United States)

    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. .

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

    Science.gov (United States)

    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.

  14. Experimental results for an experimental condensation heat exchanger with a spiral minichanel tube. Comparison to numerical imulations

    Directory of Open Access Journals (Sweden)

    Hrubý J.

    2013-04-01

    Full Text Available The paper describes new results for an experimental heat exchanger equipped with a single corrugated capillary tube, basic information about the measurements and the experimental setup. Some of the results were compared with numerical simulations.

  15. Bilateral cochlear implantation: current concepts, indications, and results.

    Science.gov (United States)

    Basura, Gregory J; Eapen, Rose; Buchman, Craig A

    2009-12-01

    The optimal treatment for bilateral hearing loss continues to evolve as cochlear implant (CI) and hearing aid technologies advance, as does our understanding of the central auditory system. Ongoing discussions continue on the validity and feasibility of bilateral CI in terms of performance, justification of need, medical/surgical safety concerns, and economics. The purpose of this review article is to provide an update on the advantages and disadvantages of bilateral CI and to provide a discussion on timing (simultaneous vs. sequential), technology (bimodal vs. binaural) and feasibility. Binaural advantages are found in both adult and pediatric bilateral CI recipients, the greatest being the head shadow effect and improvements in localization and loudness summation. This theoretically offers an advantage over their unilateral implanted counterparts in terms of improved sound localization and enhanced speech perception under noisy conditions. Most investigators agree that bilateral stimulation during critical periods of development is paramount for optimizing auditory functioning in children. Currently, bilateral CI is widely accepted as a safe and effective means of bilateral auditory stimulation.

  16. Numerical simulation and experimental validation of a direct current air corona discharge under atmospheric pressure

    Institute of Scientific and Technical Information of China (English)

    Liu Xing-Hua; He Wei; Yang Fan; Wang Hong-Yu; Liao Rui-Jin; Xiao Han-Guang

    2012-01-01

    Air corona discharge is one of the critical problems associated with high-voltage equipment.Investigating the corona mechanism plays a key role in enhancing the electrical insulation performance.An improved self-consistent multi-component two-dimensional plasma hybrid model is presented for the simulation of a direct current atmospheric pressure corona discharge in air.The model is based on plasma hydrodynamic and chemical models,and includes 12 species and 26 reactions.In addition,the photoionization effect is introduced into the model.The simulation on a bar-plate electrode configuration with an inter-electrode gap of 5.0 mm is carried out.The discharge voltage-current characteristics and the current density distribution predicted by the hybrid model agree with the experimental measurements.In addition,the dynamics of volume charged species generation,discharge current waveform,current density distribution at an electrode,charge density,electron temperature,and electric field variations are investigated in detail based on the model.The results indicate that the model can contribute valuable insights into the physics of an air plasma discharge.

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

    Science.gov (United States)

    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.

  18. Comparison of experimental and theoretical gain-current relations in GaInP quantum well lasers

    Energy Technology Data Exchange (ETDEWEB)

    Smowton, P.M.; Chow, W.W.; Blood, P.

    2000-01-10

    The authors compare the results of a microscopic laser theory with gain and recombination currents obtained from experimental spontaneous emission spectra. The calculated absorption spectrum is first matched to that measured on a laser, ensuring that the quasi-Fermi levels for the calculation and the experiment (spontaneous emission and gain) are directly related. This allows one to determine the inhomogeneous broadening in their experimental samples. The only other inputs to the theory are literature values of the bulk material parameter. The authors then estimate the non-radiative recombination current associated with the well and wave-guide core from a comparison of measured and calculated recombination currents.

  19. Immobilized cell technology in beer brewing: Current experience and results

    Directory of Open Access Journals (Sweden)

    Leskošek-Čukalov Ida J.

    2005-01-01

    Full Text Available Immobilized cell technology (ICT has been attracting continual attention in the brewing industry over the past 30 years. Some of the reasons are: faster fermentation rates and increased volumetric productivity, compared to those of traditional beer production based on freely suspended cells, as well as the possibility of continuous operation. Nowadays, ICT technology is well established in secondary fermentation and alcohol- free and low-alcohol beer production. In main fermentation, the situation is more complex and this process is still under scrutiny on both the lab and pilot levels. The paper outlines the most important ICT processes developed for beer brewing and provides an overview of carrier materials, bioreactor design and examples of their industrial applications, as well as some recent results obtained by our research group. We investigated the possible applications of polyvinyl alcohol in the form of LentiKats®, as a potential porous matrices carrier for beer fermentation. Given are the results of growth studies of immobilized brewer's yeast Saccharomyces uvarum and the kinetic parameters obtained by using alginate microbeads with immobilized yeast cells and suspension of yeast cells as controls. The results indicate that the immobilization procedure in LentiKat® carriers has a negligible effect on cell viability and growth. The apparent specific growth rate of cells released in medium was comparable to that of freely suspended cells, implying preserved cell vitality. A series of batch fermentations performed in shaken flasks and an air-lift bioreactor indicated that the immobilized cells retained high fermentation activity. The full attenuation in green beer was reached after 48 hours in shaken flasks and less than 24 hours of fermentation in gas-lift bioreactors.

  20. Current concepts, classification, and results in short stem hip arthroplasty.

    Science.gov (United States)

    Falez, Francesco; Casella, Filippo; Papalia, Matteo

    2015-03-01

    Various short hip stems have been introduced with differing implant concepts of femoral fixation and implant length. There is a lack of proper classification for short hip stems, with a clear and accepted definition for implant length and extent of bone preservation in the metaphyseal and diaphyseal femur. This study analyzed the length of short hip stems. Stems were divided into collum, partial collum, and trochanter-sparing implants. An additional category was added, trochanter harming, which was defined as interruption of the circumferential integrity of the femoral neck. For all of the femoral components described, the designs were compared, excluding stems with insufficient clinical data. The 15 finally selected stems were classified as collum (1 stem), partial collum (7 stems), trochanter sparing (4 stems), and trochanter harming (3 stems). Mid-term results (>5 years of follow-up) were available for only 3 designs in the partial collum group. Taking into account the results of short-term studies (<5 years of follow-up), the femoral revision rate per 100 observed component years was <1 for most total hip arthroplasties. However, the studies varied greatly regarding level of significance, and short hip stems without published results are available commercially. Short hip stems cannot be circumscribed by a simple length limit. For some designs, clinical data collected from large patient cohorts showed a survivorship comparable to traditional stems. In cases that must be revised, this often can be performed with a conventional primary stem, fulfilling the promise to preserve bone for potential future revisions in younger patients.

  1. New results on inclusive nu Fe charged current interactions

    CERN Document Server

    Abramowicz, H; De Groot, J G H; Dydak, F; Eisele, F; Flottmann, T; Geweniger, C; Guyot, C; He, J T; Klasen, H; Kleinknecht, K; Knobloch, J; Królikowski, J; Lierl, H; May, J; Merlo, J P; Palazzi, P; Para, A; Peyaud, B; Pszola, B; Rander, J; Ranjard, F; Rothberg, J E; Ruan, T Z; Schlatter, W D; Schuller, J P; Steinberger, J; Tittel, K; Turlay, René; von Rüden, Wolfgang; Wahl, H; Willutzki, H J; Wotschack, J; Wu, W M

    1981-01-01

    Based on 60000(25000) nu ( nu ) events obtained recently in the CERN 200 GeV narrow band neutrino beam, the authors present new results on the nucleon structure functions F/sub 2/(x, Q/sup 2/) and xF/sub 3/(x, Q/sup 2/) and on the Callan Gross relation. The observed scaling violations of F/sub 2/ and xF/sub 3/ are interpreted in terms of QCD. The strong coupling constant alpha /sub s/ is measured in agreement with the QCD predicted behaviour. (8 refs).

  2. Currents, HF Radio-derived, Monterey Bay, 1 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  3. Currents, HF Radio-derived, SF Bay, 1 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  4. Currents, HF Radio-derived, SF Bay Outlet, 1 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  5. Currents, HF Radio-derived, SF Bay Outlet, 1 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  6. Currents, HF Radio-derived, Bodega Bay, 1 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  7. Currents, HF Radio-derived, Bodega Bay, 1 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  8. Currents, HF Radio-derived, Ano Nuevo, 1 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  9. Currents, HF Radio-derived, Ano Nuevo, 1 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  10. Early Results in Capella's Prior Learning Assessment Experimental Site Initiative

    Science.gov (United States)

    Klein, Jillian

    2017-01-01

    In July 2014, the U.S. Department of Education announced a new round of experimental sites focusing on competency-based education. Capella University was selected to participate in three of the Department of Education's competency-based education (CBE) experiments and began by implementing the prior learning assessment experiment, which allows…

  11. Stemless shoulder arthroplasty-current results and designs.

    Science.gov (United States)

    Churchill, R Sean; Athwal, George S

    2016-03-01

    Stemless shoulder arthroplasty was originally introduced in 2004 by a single manufacturer. Now, over a decade later, numerous designs are available outside the USA, but as yet, only one implant has been cleared by the Food and Drug Administration (FDA) and is available for use within the USA. Often referred to as "canal sparing," these implants are designed for metaphyseal fixation to minimize humeral bone removal, avoid intraoperative and postoperative humeral fracture complications, and to decrease morbidity associated with revision operations. Recently, the second generation of stemless arthroplasty, a convertible implant allowing use in either anatomic or reverse arthroplasty configuration, was released for use outside the USA. This paper will review the available designs, reported results, and raise potential concerns for this emerging technology.

  12. Deep penetrating eddy current for copper canister inspection. Main results

    Energy Technology Data Exchange (ETDEWEB)

    Tadeusz Stepinski [TSonic, Uppsala (Sweden)

    2004-02-01

    The aim of this project was to optimize the detection and characterization of deep flaws (voids) in copper plates. Two types of voids were investigated and compared: circular and rectangular. The circular voids had the form of cylindrical cavities while the rectangular ones were cavities with a rectangular cross section. All probes were of the same type, transmit-receive transducers with four pick-ups connected in a double differential configuration. Comparison of the EC responses to circular and rectangular voids obtained using the MDF12 probe has shown that both types of voids can be characterized using phase and amplitude of their responses in the complex impedance plane. Phase of the response in the impedance plane appeared to be a reliable measure of void depth. Phase dependence on the void depth is linear (which agrees with the theory) and its slope is approx -37 deg/mm. Magnitude of the EC response contains information on the void size provided that the void depth is known. It has been shown that magnitude of the EC responses is correlated to the lengths of the rectangular voids and hole diameter, this is, similar lengths and diameters result in similar response magnitudes. It should be noted, however, that multi-differential MDF probes generate responses with different shapes for circular and rectangular voids. First, shapes of the MDF probe responses in the impedance plane depend on the probe's orientation with respect to scanning direction. Second, they also depend upon the direction of scanning with respect to the void orientation. The measurements presented in this report were performed for the probe axis aligned along with the scanning direction and, in case of rectangular voids, for scanning direction along the void lengths. Comparison of the responses obtained from flat bottom holes in copper material taken from different canister parts has not shown any essential differences between the material samples. Conductivity measurement performed using

  13. CP Violation in B Meson Decays: Experimental Results

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Timelike Compton Scattering - New Theoretical Results and Experimental Possibilities

    CERN Document Server

    Pire, Bernard; Wagner, Jakub

    2012-01-01

    We review recent progress in the study of timelike Compton scattering (TCS), the crossed process of deeply virtual Compton scattering. We emphasize the need to include NLO corrections to any phenomenological program to extract Generalized Parton Distributions (GPDs) from near future experimental data. We point out that TCS at high energy should be available through a study of ultraperipheral collisions at RHIC and LHC, opening a window on quark and gluon GPDs at very small skewness.

  15. Experimental results of guided wave travel time tomography

    NARCIS (Netherlands)

    Volker, A.W.F.; Mast, A.; Bloom, J.G.P.

    2009-01-01

    Corrosion is one of the industries major issues regarding the integrity of assets. Currently inspections are conducted at regular intervals to ensure a sufficient integrity level of these assets. Both economical and social requirements are pushing the industry to even higher levels of availability,

  16. Experimental results of guided wave travel time tomography

    NARCIS (Netherlands)

    Volker, A.W.F.; Vos, H.

    2011-01-01

    Corrosion is one of the industries major issues regarding the integrity of assets. Currently inspections are conducted at regular intervals to ensure a sufficient integrity level of these assets. Cost reduction while maintaining a high level of reliability and safety of installations is a major chal

  17. Observer Based Sliding Mode Attitude Control: Theoretical and Experimental Results

    Directory of Open Access Journals (Sweden)

    U. Jørgensen

    2011-07-01

    Full Text Available In this paper we present the design of a sliding mode controller for attitude control of spacecraft actuated by three orthogonal reaction wheels. The equilibrium of the closed loop system is proved to be asymptotically stable in the sense of Lyapunov. Due to cases where spacecraft do not have angular velocity measurements, an estimator for the generalized velocity is derived and asymptotic stability is proven for the observer. The approach is tested on an experimental platform with a sphere shaped Autonomous Underwater Vehicle SATellite: AUVSAT, developed at the Norwegian University of Science and Technology.

  18. Characterization and experimental results in PEM fuel cell electrical behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Kunusch, Cristian; Puleston, Paul F.; More, Jeronimo J. [LEICI, Departamento de Electrotecnia, Universidad Nacional de La Plata, calle 48 y 116 s/n (CC 91), La Plata B1900TAG (Argentina); CONICET, Consejo de Investigaciones Cientificas y Tecnicas, Av. Rivadavia 1917, Buenos Aires C1033AAJ (Argentina); Mayosky, Miguel A. [LEICI, Departamento de Electrotecnia, Universidad Nacional de La Plata, calle 48 y 116 s/n (CC 91), La Plata B1900TAG (Argentina); CICpBA, Comision de Investigaciones Cientificas de la Provincia de Buenos Aires, Calle 526 entre 10 y 11, La Plata 1900 (Argentina)

    2010-06-15

    A control oriented electrochemical static model of a proton exchange membrane fuel cell (PEMFC) stack is developed in this paper. Even though its validation is performed on a specific 7-cell PEMFC stack fed by humidified air and pure hydrogen, the methodology and fit parameters can be applied to different fuel cell systems with minor changes. The fuel cell model was developed combining theoretical considerations and semi-empirical analysis based on the experimental data. The proposed model can be successfully included into a larger dynamic subsystem to complete the power generation system. (author)

  19. Optimal active vibration absorber - Design and experimental results

    Science.gov (United States)

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

    1993-01-01

    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.

  20. Optimal active vibration absorber: Design and experimental results

    Science.gov (United States)

    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.

  1. Experimental program on debris reflooding (PEARL) results on prelude facility

    Energy Technology Data Exchange (ETDEWEB)

    Repetto, G.; Garcin, T.; Eymery, S.; March, P.; Fichot, F., E-mail: georges.repetto@irsn.fr, E-mail: thierry.garcin@irsn.fr, E-mail: philippe.march@irsn.fr, E-mail: stephane.eymery@irsn.fr, E-mail: florian.fichot@irsn.fr [Inst. de Radioprotection et de Surete Nucleaire, Cadarache (France)

    2011-07-01

    The “Institut de Radioprotection et de Surete Nucleaire” is developing simulation tools to be used in the safety studies, for the optimization of the Severe Accident Management strategy and to assess the probabilities to stop the progress of In-vessel core degradation in a Nuclear Power Plant. The objective of the experimental program PEARL is to extend the validation of debris reflooding models in 2D and 3D situations. The aim is to predict the consequences of the water reflooding of a severely damaged reactor core where a significant part of the core has collapsed and formed a debris bed. (author)

  2. Review of JT-60U experimental results in 1997

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, H.; Akasaka, H.; Akino, N. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment] [and others

    1998-08-01

    The JT-60U experiments in 1997 focused mainly on the steady-state tokamak research with the newly installed W-shaped pumped divertor and the negative ion based neutral beam (NNB) in addition to the existing profile and shape control techniques developed in JT-60U. In particular, the research on divertor physics was accelerated under the new divertor system with many of fine diagnostics: Detachment characteristics, pumping control, impurity control, recycling characteristics, etc. in the W-shaped divertor were investigated in detail. The main purpose of confinement and stability studies in 1997 was to improve steadiness of high confinement plasmas with the new divertor. Researches progressed also for the formation conditions of the internal and the surface transport barriers in the high-{beta}{sub p} mode, the reversed shear mode and the H-mode. Toward the advanced feedback controls of multiple parameters, the JT-60U started new feedback controls of central line density and divertor neutral gas pressure in addition to the existing controls of off-axis line density, radiation power and neutron production rate. The JT-60U team also carefully studied characteristics of halo current during disruptions. Optimization of NNB operation progressed steadily and injection power increased up to 4.2MW. The NNB-driven current was identified directly from the internal magnetic measurement and driven current profile was confirmed to be consistent with the ACCOME calculation. The current profile control with LHCD successfully sustained the internal transport barrier in reversed shear plasmas. Continuous TAE modes were observed with NNB for the first time as beam-driven TAE modes. (J.P.N.)

  3. Overview of recent experimental results from the Aditya tokamak

    Science.gov (United States)

    Tanna, R. L.; Ghosh, J.; Chattopadhyay, P. K.; Raj, Harshita; Patel, Sharvil; Dhyani, P.; Gupta, C. N.; Jadeja, K. A.; Patel, K. M.; Bhatt, S. B.; Panchal, V. K.; Patel, N. C.; Chavda, Chhaya; Praveenlal, E. V.; Shah, K. S.; Makawana, M. N.; Jha, S. K.; Gopalkrishana, M. V.; Tahiliani, K.; Sangwan, Deepak; Raju, D.; Nagora, Umesh; Pathak, S. K.; Atrey, P. K.; Purohit, S.; Raval, J.; Joisa, Y. S.; Rao, C. V. S.; Chowdhuri, M. B.; Banerjee, S.; Ramaiya, N.; Manchanda, R.; Thomas, J.; Kumar, Ajai; Ajay, Kumar; Sharma, P. K.; Kulkarni, S. V.; Sathyanarayana, K.; Shukla, B. K.; Das, Amita; Jha, R.; Saxena, Y. C.; Sen, A.; Kaw, P. K.; Bora, D.; the ADITYA Team

    2017-10-01

    Several experiments, related to controlled thermonuclear fusion research and highly relevant for large size tokamaks, including ITER, have been carried out in ADITYA, an ohmically heated circular limiter tokamak. Repeatable plasma discharges of a maximum plasma current of ~160 kA and discharge duration beyond ~250 ms with a plasma current flattop duration of ~140 ms have been obtained for the first time in ADITYA. The reproducibility of the discharge reproducibility has been improved considerably with lithium wall conditioning, and improved plasma discharges are obtained by precisely controlling the position of the plasma. In these discharges, chord-averaged electron density ~3.0-4.0  ×  1019 m-3 using multiple hydrogen gas puffs, with a temperature of the order of ~500-700 eV, have been achieved. Novel experiments related to disruption control are carried out and disruptions, induced by hydrogen gas puffing, are successfully mitigated using the biased electrode and ion cyclotron resonance pulse techniques. Runaway electrons are successfully mitigated by applying a short local vertical field (LVF) pulse. A thorough disruption database has been generated by identifying the different categories of disruption. Detailed analysis of several hundred disrupted discharges showed that the current quench time is inversely proportional to the q edge. Apart from this, for volt-sec recovery during the plasma formation phase, low loop voltage start-up and current ramp-up experiments have been carried out using electron cyclotron resonance heating (ECRH). Successful recovery of volt-sec leads to the achievement of longer plasma discharge durations. In addition, the neon gas puff assisted radiative improved confinement mode has also been achieved in ADITYA. All of the above mentioned experiments will be discussed in this paper.

  4. Flux quantum tunneling effect and its influence on the experimental critical current density

    Institute of Scientific and Technical Information of China (English)

    闻海虎; 赵忠贤; GriessenR.

    1995-01-01

    By using magnetic sweeping method, the temperature and magnetic field dependencies of the experimental current density and the normalized relaxation rate have been obtained. The true critical current density corresponding to the zero activation energy has been carried out based on the collective-pinning and the thermally-activated flux motion models, and therefore the influences of the quantum tunneling effect and the thermal activation effect on the experimental critical current density are distinguished. It is found that, with temperature lower than 10 K, the relaxation rate will not drop to zero when T approaches zero K because of the occurrence of the flux quantum tunneling. This additional flux motion further reduces the experimental critical current density j making it saturated with lowering temperature.

  5. CSI Flight Computer System and experimental test results

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  7. The ISR Asymmetrical Capacitor Thruster: Experimental Results and Improved Designs

    Science.gov (United States)

    Canning, Francis X.; Cole, John; Campbell, Jonathan; Winet, Edwin

    2004-01-01

    A variety of Asymmetrical Capacitor Thrusters has been built and tested at the Institute for Scientific Research (ISR). The thrust produced for various voltages has been measured, along with the current flowing, both between the plates and to ground through the air (or other gas). VHF radiation due to Trichel pulses has been measured and correlated over short time scales to the current flowing through the capacitor. A series of designs were tested, which were increasingly efficient. Sharp features on the leading capacitor surface (e.g., a disk) were found to increase the thrust. Surprisingly, combining that with sharp wires on the trailing edge of the device produced the largest thrust. Tests were performed for both polarizations of the applied voltage, and for grounding one or the other capacitor plate. In general (but not always) it was found that the direction of the thrust depended on the asymmetry of the capacitor rather than on the polarization of the voltage. While no force was measured in a vacuum, some suggested design changes are given for operation in reduced pressures.

  8. Preliminary Experimental Results for Indirect Vector-Control of Induction Motor Drives with Forced Dynamics

    Directory of Open Access Journals (Sweden)

    Jan Vittek

    2003-01-01

    Full Text Available The contribution presents an extension of indirect vector control of electric drives employing induction motors to 'Forced Dynamic Control'. This method of control offers an accurate realisation of dynamic response profiles, which can be selected by the user. The developed system can be integrated into a drive with a shaft position encoder or a shaft sensoriess drive, in which only the stator currents are measured. The applied stator voltages are determined by a computed inverter switching algorithm. Simulation results and preliminary experimental results for indirect vector control of an idle running induction motor indicate good agreement with the theoretical predictions.

  9. Forward and inverse problems in MHD: numerical and experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Stefani, F.; Gerbeth, G.; Gundrum, T.; Xu, M. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany); Gailitis, A. [Inst. of Physics, Latvian Univ., Salaspils (Latvia)

    2007-07-01

    When a conducting fluid comes under the influence of a magnetic field, electrical currents are induced that give rise to a modification of this magnetic field. The ratio of induced magnetic field to applied magnetic field is characterized by the magnetic Reynolds number Rm of the flow. For large Rm, even self-excitation of a magnetic field can occur. This hydromagnetic dynamo effect is responsible for the maintenance of the magnetic fields of planets, stars and galaxies. In the present paper, we delineate some recent developments in the numerical treatment of induction effects in arbitrary geometry, and their application for dynamo experiments as well as for a ''contactless inductive flow tomography (CIFT).'' (orig.)

  10. General Motors sulfate dispersion experiment: experimental procedures and results

    Energy Technology Data Exchange (ETDEWEB)

    Cadle, S.H.; Chock, D.P.; Monson, P.R.; Heuss, J.M.

    1977-01-01

    A massive experiment was conducted at the General Motors Proving Ground to measure the dispersion of sulfates generated by catalyst equipped vehicles. 352 cars equipped with catalysts and air pumps were driven on a 10 kilometer test track to provide a simulated freeway situation with a traffic density of 5462 cars/hour. Experiments were conducted on 17 days in October 1975, providing sixty-six 30 min data sets. On most days, the experiment was carried out early in the morning in order to run under the most adverse meteorological conditions available. Samples of airborne sulfate and a gas tracer, sulfur hexafluoride, as well as extensive meteorological data were collected simultaneously at 20 sampling points under a wide variety of meteorological conditions. The maximum measured increase in sulfate from each 30 min data set was generally found next to the roadway at the lowest level and varied from 3 to 15 ..mu..g/m/sup 3/. This increase in sulfate over background fell off rapidly with height and distance. Sulfate increases in vehicles (2 hr averages) ranged from 0 to 20 ..mu..g/m/sup 3/, and averaged 4 ..mu..g/m/sup 3/. Within experimental uncertainty, the sulfate aerosol and the gas tracer were found to disperse in the same manner. The tracer data have also been used to calculate the sulfate emission rate of the vehicles.

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

    Directory of Open Access Journals (Sweden)

    R. Silva-Ortigoza

    2013-01-01

    Full Text Available 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.

  12. Recent Experimental Results in the VX-10 Device

    Science.gov (United States)

    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.

  13. Review of JT-60U experimental results in 1998

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, H.; Akasaka, H.; Akino, N. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment] [and others

    1999-09-01

    Based on the high confinement regimes such as reversed shear mode, high-{beta}{sub p} mode and H-mode, the JT-60U experiment in 1998 was devoted to expand the discharge regimes in terms of 1) achievement of high fusion gain, 2) concept optimization for long sustainment of the advanced modes for >>{tau}{sub E} and >{tau}{sub p}* with the current profile close to the steady-state solution, 3) high confinement by electron heating (T{sub e}>T{sub i}), 4) high confinement at high electron density and/or at high divertor radiation and 5) active control of multiple parameters including both core and divertor plasmas. As for the reversed shear mode, high performance discharges satisfying Q{sub DT}{sup eq} (DT equivalent fusion gain ) >1 were obtained reproducibly and the record value of Q{sub DT}{sup eq}=1.25 was achieved in a reactor-relevant thermonuclear dominant regime due to the optimized discharge scenario using feedback control of the neutron production rate where {beta}-values were kept in the MHD stable region during the I{sub p} ramping phase with a large radius of the internal transport barrier (ITB). The reduction of Z{sub eff} obtained after installation of W-shaped pumped divertor increased fusion reaction rate. Concerning long sustainment, the reversed shear ELMy H-mode with H{sup 89PL}-factor{approx}1.5-2 and {beta}{sub N}=1.0-1.4 was kept for 5.5 s with NB heating. By off axis LH current drive, the reversed shear current profile with the ITB was kept constant for 4.7 s under full non- inductive current drive condition (LHCD=77%, bootstrap=23%) at T{sub e}-1.2T{sub i}. In the high-{beta}{sub p} ELMy H-mode regime, benefits of the high triangularity shape were demonstrated. At a high triangularity {delta}{sub X}{approx}0.46, {beta}{sub N}=2.5-2.7 was sustained for 3.5 s even at the low value of q{sub 95}=2.9-3.3. The product of {beta}{sub N}xH-factor sustainable for >5{tau}{sub E} (>{tau}{sub p}*) increases with {delta}{sub x} and reaches {approx}6 at {delta

  14. A review of experimental results at the knee

    CERN Document Server

    Hörandel, J R

    2005-01-01

    Results of experiments investigating air showers in the energy region of the knee are summarized. The all-particle energy spectrum, the mean logarithmic mass, and the average depth of the shower maximum will be discussed. Spectra for groups of elements from air shower data are compared to results from direct measurements.

  15. Advanced Supersonic Nozzle Concepts: Experimental Flow Visualization Results Paired With LES

    Science.gov (United States)

    Berry, Matthew; Magstadt, Andrew; Stack, Cory; Gaitonde, Datta; Glauser, Mark; Syracuse University Team; The Ohio State University Team

    2015-11-01

    Advanced supersonic nozzle concepts are currently under investigation, utilizing multiple bypass streams and airframe integration to bolster performance and efficiency. This work focuses on the parametric study of a supersonic, multi-stream jet with aft deck. The single plane of symmetry, rectangular nozzle, displays very complex and unique flow characteristics. Flow visualization techniques in the form of PIV and schlieren capture flow features at various deck lengths and Mach numbers. LES is compared to the experimental results to both validate the computational model and identify limitations of the simulation. By comparing experimental results to LES, this study will help create a foundation of knowledge for advanced nozzle designs in future aircraft. SBIR Phase II with Spectral Energies, LLC under direction of Barry Kiel.

  16. Experimental identification of an azimuthal current in a magnetic nozzle of a radiofrequency plasma thruster

    Science.gov (United States)

    Takahashi, Kazunori; Chiba, Aiki; Komuro, Atsushi; Ando, Akira

    2016-10-01

    The azimuthal plasma current in a magnetic nozzle of a radiofrequency plasma thruster is experimentally identified by measuring the plasma-induced magnetic field. The axial plasma momentum increases over about 20 cm downstream of the thruster exit due to the Lorentz force arising from the azimuthal current. The measured current shows that the azimuthal current is given by the sum of the electron diamagnetic drift and \\mathbf{E}× \\mathbf{B} drift currents, where the latter component decreases with an increase in the magnetic field strength; hence the azimuthal current approaches the electron diamagnetic drift one for the strong magnetic field. The Lorentz force calculated from the measured azimuthal plasma current and the radial magnetic field is smaller than the directly measured force exerted to the magnetic field, which indicates the existence of a non-negligible Lorentz force in the source tube.

  17. STATISTICAL ANALYSIS OF SOME EXPERIMENTAL FATIGUE TESTS RESULTS

    OpenAIRE

    Adrian Stere PARIS; Gheorghe AMZA; Claudiu BABIŞ; Dan Niţoi

    2012-01-01

    The paper details the results of processing the fatigue data experiments to find the regression function. Application software for statistical processing like ANOVA and regression calculi are properly utilized, with emphasis on popular software like MSExcel and CurveExpert

  18. Experimental Results from Initial Operation of Plasma Injector 1

    Science.gov (United States)

    Howard, Stephen

    2010-11-01

    General Fusion has begun operation of its first full-scale plasma injector, designed to accelerate high density spheromak plasmas into the compression chamber of a proposed MTF reactor. The geometry of Plasma Injector 1 (PI-1) is that of a two stage coaxial Marshal gun with a conical converging accelerator electrodes, similar in shape to the MARAUDER device, while pulsed power is applied in the same configuration as the RACE device. PI-1 is 5 meters in length and 1.9 m in diameter at the expansion region where a high aspect ratio (4.4) spheromak is formed with a minimum lambda of 9 m-1. The acceleration/compression stage is 4 m long and tapers to a final outer diameter of 40 cm. PI-1 is now operating at 1 MJ of total capacitor power, which will be doubled again before it reaches its design parameters. Diagnostics include 3 interferometer chords, 21 magnetic probes (2 axis poloidal/toroidal), 13 fast photodiode chords, as well as one Thomson scattering chord, a visible light survey spectrometer, and a Langmuir triple probe. Electrode voltage and current are also monitored. So far spheromaks of poloidal flux exceeding 100 mWb have been formed in the expansion region, and spheromaks of 40-50 mWb have been formed and accelerated out the end of the accelerator into a flux conserving target chamber. Expansion region densities are typically ˜5 x10^14cm-3, while conditions in the target chamber have reached ne˜10^16cm-3, and lifetimes of 300 μs.

  19. Experimental Investigation and Modelling for the Optimisation of Conduction Cooled HTS Hybrid Current Leads for SMES

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    It′s important that HTS tapes have lower thermal conductivity and higher transversal resistivity in order to reduce the heat leaks conducted along the tapes and AC losses in the high temperature superconducting system conduction-cooled by GM coolers. This paper presents an experimental investigation into the effects of pure Ag and AgAu alloys sheath materials on the properties of Bi(2223) multifilamentary tapes and the optimisation of conduction-cooled hybrid current leads made from copper and Bi(2223)/Ag or Bi(2223)/AgAu tapes. The thermal conductivity of the tapes were measured by cryogenic steady heat flux method and the resistance was measured by using standard DC four-probe method at low temperature. The results showed that the reduction of thermal conductivity by the addition of Au into the sheath material of Bi(2223) tapes was 650%, 750% and 850% lower than that of pure Ag sheathed Bi(2223) tapes and the increase of resistivity was 4.9, 10 and 19.4 times higher than that of pure Ag for the addition of 2.20%, 5.70% and 10.70%Au(atom ratio) respectively. And the study also attempts to optimise thermodynamically the conduction-cooled hybrid current lead by using a developed model, which took the irreversibility of commercial GM coolers, the contact resistance and thermal conductance into account. Predictions from the model showed that AgAu alloys were suitable candidate materials to replace Ag as sheath material of Bi(2223) tapes applied in HTS current leads. In addition, Bi(2223)/AgAu was a suitable material to be applied as the HTS section of hybrid current leads in conduction-cooled superconducting electric systems.

  20. Seismic techniques of enhanced oil recovery: experimental and field results

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, O.L.; Simkin, E.M.; Chilingar, G.V.; Gorfunkel, M.V.; Robertson, J.O. Jr.

    2002-09-15

    Application of secondary and tertiary oil recovery techniques during late field development stages usually yields poor results. The reasons are principally due to the low efficiency of these technologies, probably because the gravity and capillary forces are not properly considered. Improved efficiency for hydrocarbon recovery produced by seismic vibration is discussed. (author)

  1. STATISTICAL ANALYSIS OF SOME EXPERIMENTAL FATIGUE TESTS RESULTS

    Directory of Open Access Journals (Sweden)

    Adrian Stere PARIS

    2012-05-01

    Full Text Available The paper details the results of processing the fatigue data experiments to find the regression function. Application software for statistical processing like ANOVA and regression calculi are properly utilized, with emphasis on popular software like MSExcel and CurveExpert

  2. Experimental Study on Vortex-Induced Vibrations of Submarine Pipeline near Seabed Boundary in Ocean Currents

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Unlike most previous studies on vortex-induced vibrations of a cylinder far from a boundary, this paper focuses on the influences of close proximity of a submarine pipeline to a rigid seabed boundary upon the dynamic responses of the pipeline in ocean currents. The effects of gap-to-diameter ratio and those of the stability parameter on the amplitude and frequency responses of a pipeline are investigated experimentally with a novel hydro-elastic facility. A comparison is made between the present experimental results of the amplitude and frequency responses for the pipes with seabed boundary effects and those for wall-free cylinders given by Govardhan and Williamson (2000) and Anand (1985). The comparison shows that the close proximity of a pipeline to seabed has much influence on the vortex-induced vibrations of the pipeline. Both the width of the lock-in ranges in terms of Vr and the dimensionless amplitude ratio Amax/D become larger with the decrease of the gap-to-diameter ratio e/D. Moreover, the vibration of the pipeline becomes easier to occur and its amplitude response becomes more intensive with the decrease of the stability parameter, while the pipeline frequency responses are affected slightly by the stability parameter.

  3. Diamond mosaic crystals for neutron instrumentation: First experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Freund, A.K., E-mail: kafreund@free.f [Via Cordis, 92 Rue Abbe de l' Epee, F-33000 Bordeaux (France); Institut Max von Laue-Paul Langevin, B.P. 156, F-38042 Grenoble Cedex (France); Gsell, S.; Fischer, M.; Schreck, M. [Institut fuer Physik, Universitaet Augsburg, D-86135 Augsburg (Germany); Andersen, K.H.; Courtois, P. [Institut Max von Laue-Paul Langevin, B.P. 156, F-38042 Grenoble Cedex (France); Borchert, G. [Forschungsneutronenquelle FRM2, D-85747 Garching (Germany); Skoulatos, M. [Helmholtz Center Berlin for Materials and Energy, D-14109 Berlin (Germany)

    2011-04-01

    Diamond single crystals were recently proposed as monochromators of unprecedented performance (Freund, 2009). In the present paper we describe how diamond crystals with a suitable mosaic spread can be produced using a specific plasma CVD technique. Up to 2 mm thick samples with an average mosaic spread of 0.2{sup o} have been produced. We report on X- and gamma-ray characterisation checking the uniformity of the mosaic structure and present the results of a first study regarding the neutron reflection properties of this outstanding material. These promising results show that the diamond diffraction properties are not too far from the theoretical expectations. For example, 34% peak reflectivity has been obtained for a 1 mm thick crystal at 1 A wavelength.

  4. Design and Experimental Results for the S407 Airfoil

    Science.gov (United States)

    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

  5. Boston Community Information System 1986 Experimental Test Results.

    Science.gov (United States)

    1987-08-01

    participants in the Boston CommnS. The questionnaire results showed a large interest in major corporations such as IBM, Digital Equipment, Data...DATA FROM THE FIS YEAR ’Computer, Electronic, Accounting’ - 1132 OIEEE Proceedings, Science, Communicatins of the ACM’ - 1137 ’American Political...higher if corporate . Since I moved it to the ofice to shape data with our [Oxfam Americal Press office and Ex. Dir. I have lez discretionary leisure

  6. Simulation and experimental results of hybrid electric machine with a novel flux control strategy

    Directory of Open Access Journals (Sweden)

    Paplicki Piotr

    2015-03-01

    Full Text Available The paper presents selected simulation and experimental results of a hybrid ECPMS-machine (Electric Controlled Permanent Magnet Synchronous Machine. This permanent magnets (PMs excited machine offers an extended magnetic field control capability which makes it suitable for battery electric vehicle (BEV drives. Rotor, stator and the additional direct current control coil of the machine are analyzed in detail. The control system and strategy, the diagram of power supply system and an equivalent circuit model of the ECPMS-machine are presented. Influence of the additional excitation on the performance parameters of the machine, such as: torque, efficiency, speed limits and back-EMF have also been discussed.

  7. HAMLET -Human Model MATROSHKA for Radiation Exposure Determination of Astronauts -Current status and results

    Science.gov (United States)

    Reitz, Guenther; Berger, Thomas; Bilski, Pawel; Burmeister, Soenke; Labrenz, Johannes; Hager, Luke; Palfalvi, Jozsef K.; Hajek, Michael; Puchalska, Monika; Sihver, Lembit

    contribute essentially to radiation risk estimations for future interplanetary space exploration by humans, putting them on a solid experimental and theoretical basis. The talk will give an overview of the current status of the MATROSHKA data evaluation and results and comparisons of the first three MTR experimental phases (MTR-1, 2A and 2B). The HAMLET project is funded by the European Commission under the EUs Seventh Frame-work Programme (FP7) under Project Nr: 218817 and coordinated by the German Aerospace Center (DLR) http://www-fp7-hamlet.eu

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

    CERN Document Server

    Sonsky, J; Huizenga, John R; Hollander, R W; 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 sup + 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 mu m, we have measured the maximum number of fully confined electrons as a function of the potential gutter depth induced by different sawtooth angles.

  9. Numerical Simulation of Micronozzles with Comparison to Experimental Results

    Science.gov (United States)

    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.

  10. The Italsat network: A first analysis of the experimental results

    Science.gov (United States)

    Soccodato, G.; Saitto, A.; Melani, M.; Maritti, M.

    1991-10-01

    The Italsat system, after four years of development has reached is final phase. The satellite was launched at the beginning of 1991, the first traffic stations being installed at the end of the Summer of 1991. Considering that this is the first time that a regenerative payload will be used on a communications satellite, a long test campaign was carried out on the ground to integrate the different components of the network, using the satellite EM payload and three traffic stations, with one of them hosting the control center. This activity was very helpful in calibrating some parameters of the regenerative payload. The test environment and philosophy are described and the major results obtained are analyzed. All is seen as the first step to integrate a network of 64 stations in the Italian domestic telephone network.

  11. Experimental Results on Statistical Approaches to Page Replacement Policies

    Energy Technology Data Exchange (ETDEWEB)

    LEUNG,VITUS J.; IRANI,SANDY

    2000-12-08

    This paper investigates the questions of what statistical information about a memory request sequence is useful to have in making page replacement decisions: Our starting point is the Markov Request Model for page request sequences. Although the utility of modeling page request sequences by the Markov model has been recently put into doubt, we find that two previously suggested algorithms (Maximum Hitting Time and Dominating Distribution) which are based on the Markov model work well on the trace data used in this study. Interestingly, both of these algorithms perform equally well despite the fact that the theoretical results for these two algorithms differ dramatically. We then develop succinct characteristics of memory access patterns in an attempt to approximate the simpler of the two algorithms. Finally, we investigate how to collect these characteristics in an online manner in order to have a purely online algorithm.

  12. Stimulating Contributions to Public Goods through Information Feedback: Some Experimental Results.

    Science.gov (United States)

    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.

  13. Numerical and experimental study of the interaction between two marine current turbines

    CERN Document Server

    Mycek, Paul; Germain, Grégory; Pinon, Grégory; Rivoalen, Elie

    2013-01-01

    The understanding of interaction effects between marine energy converters represents the next step in the research process that should eventually lead to the deployment of such devices. Although some a priori considerations have been suggested recently, very few real condition studies have been carried out concerning this issue. Trials were run on 1/30th scale models of three-bladed marine current turbine prototypes in a flume tank. The present work focuses on the case where a turbine is placed at different locations in the wake of a first one. The interaction effects in terms of performance and wake of the second turbine are examined and compared to the results obtained on the case of one single turbine. Besides, a three-dimensional software, based on a vortex method is currently being developed, and will be used in the near future to model more complex layouts. The experimental study shows that the second turbine is deeply affected by the presence of an upstream device and that a compromise between individu...

  14. First experimental results on the IShTAR testbed

    Energy Technology Data Exchange (ETDEWEB)

    D’Inca, R.; Jacquot, J.; Ochoukov, R.; Morgal, I.; Fünfgelder, H.; Faugel, H. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Crombe, K.; Louche, F.; Van Eester, D. [LPP-ERM-KMS, TEC partner, Brussels (Belgium); Heuraux, S.; Devaux, S.; Moritz, J.; Faudot, E. [Institut Jean Lamour UMR 7198 CNRS-Université de Lorraine, Nancy (France); Noterdaeme, J.-M. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Department of Applied Physics, Ghent University (Belgium)

    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.

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

    Science.gov (United States)

    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.

  16. Augmented dry cooling surface test program: analysis and experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Parry, H.L.; MacGowan, L.J.; Kreid, D.K.; Wiles, L.E.; Faletti, D.W.; Johnson, B.M.

    1979-09-01

    Experiments were performed to assess the operating characteristics and potential performance of water-augmented dry cooling systems. The work was aimed at evaluating a deluged air-cooled HOETERV plate fin heat exchanger surface proposed for integrated dry/wet cooling systems and using test results to guide the development of a predictive analytical model. In the process, all-dry performance data were obtained for the HOETERV surface as well as for two Curtiss-Wright chipped fin surfaces. The dry heat transfer data indicate that a slotted Curtiss-Wright surface slightly outperforms the HOETERV and nonslotted Curtiss-Wright surfaces based on heat rejection rate per unit of fan power. However, all three surfaces are so close in performance that other factors, such as surface cost and piping and mounting costs, will probably determine which surface is preferred at a given installation. Comparisons of deluged HOETERV performance with dry HOETERV and Curtiss-Wright performance under prototypic conditions have established that deluging can provide considerable heat rejection enhancement, particularly at low ITD and low air humidity. A deluged HOETERV core operating at a 115/sup 0/F primary fluid temperature in 105/sup 0/F air at 10% relative humidity can reject over 7 times as much heat as a dry HOETERV core operating under the same conditions at the same air-side pressure drop. Deluged tests were performed to evaluate the effect of airflow rate, deluge flow rate and core tilt angle on performance. Both increased airflow and increased deluge flow increase both heat rejection rate and required fan power. Optimal airflow rate will thus be determined for a given location by the competing costs of heat exchanger surface area versus fan operation. Changes in core tilt angle from vertical to 16/sup 0/ from vertical have a negligible effect on performance.

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

    Science.gov (United States)

    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.

  18. Impact Flash Physics: Modeling and Comparisons With Experimental Results

    Science.gov (United States)

    Rainey, E.; Stickle, A. M.; Ernst, C. M.; Schultz, P. H.; Mehta, N. L.; Brown, R. C.; Swaminathan, P. K.; Michaelis, C. H.; Erlandson, R. E.

    2015-12-01

    horizontal. High-speed radiometer measurements were made of the time-dependent impact flash at wavelengths of 350-1100 nm. We will present comparisons between these measurements and the output of APL's model. The results of this validation allow us to determine basic relationships between observed optical signatures and impact conditions.

  19. Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results

    Science.gov (United States)

    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. SUSY effects in $R_b$: revisited under current experimental constraints

    CERN Document Server

    Su, Wei

    2016-01-01

    In this note we revisit the effects of natural SUSY in $R_b$ under current experimental constraints including the LHC Higgs data, the $B$-physics measurements, the dark matter relic density and direct detection limits, as well as the precision electroweak data. We first perform a scan to figure out the currently allowed parameter space of natural SUSY and then display the SUSY effects in $R_b$. We find that although the SUSY parameter space has been severely restrained by current experimental data, natural SUSY can still alter $R_b$ with a magnitude sizable enough to be observed at future $Z$-factories (ILC, CEPC, FCC-ee, Super $Z$-factory) which produce $10^9-10^{12}$ $Z$-bosons.

  1. Survey of Experimental Results in High-Contrast Imaging for Future Exoplanet Missions

    Science.gov (United States)

    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.

  2. Erosion Control of Scour during Construction; Report 3. Experimental Measurements of Refraction, Diffraction, and Current Patterns Near Jetties.

    Science.gov (United States)

    1980-09-01

    predict the probable magnitude of (Continued) DD vi’Ra 03 1wom or INov OM @ISDETR Unclassified S.CUm TY CLAS-.lCATIO OF THIS PAS.. (..m 0. Yw...transport of the bottom material at the particular site. The purpose of this study was to obtain detailed and precise experimental data regarding wave...currents. This removal of material from around structures is often not compensated by an influx of additional material ; the result is scour, or

  3. Experimental investigations of electric current under transverse and longitudinal electric field in uniaxially deformed p-Ge

    Science.gov (United States)

    Abramov, A. A.; Akimov, V. I.; Dalakyan, A. T.; Tulupenko, Victor N.; Zaitsev, A. M.; Danilov, S. N.; Firsov, D. A.; Shalygin, V. A.

    1999-11-01

    Comparison between cases of longitudinal and transverse directions of uniaxial pressure and strong electric field, affected the bulk hole germanium, to use it for lasting in far IR region has been carried out. Conclusion about preference of crossed directions is made. Threshold pressure, at which stimulated radiation arises, independence of crystallographic direction, along which external influences are applied, is also discussed. The results of experimental investigations of the crossed directions of uniaxial pressure and electric current are given.

  4. Experimental study on a wide range of wave and current conditions of the WEPTOS Wave Energy Converter

    DEFF Research Database (Denmark)

    Pecher, Arthur; Kofoed, Jens Peter

    This report presents the results of an experimental study that was performed on small scale model that was a replication of the full-scale Weptos WEC intended for DanWEC. The tests were performed in the circular basin at FloWave at Edinburgh University in October 2014. The laboratory facilities h...... the capabilities to have simultaneously currents and waves from any possible direction and also to produce advanced wave specifications....

  5. High performance predictive current control of a three phase VSI: An experimental assessment

    Indian Academy of Sciences (India)

    Vikas Kumar; Prerna Gaur; A P Mittal

    2014-12-01

    Delay has a significant role to play in the implementation of the predictive current control scheme as large amount of calculations are involved. Compensating delay in the predictive current controller design can lead to an improved load current total harmonic distortion (THD) and also an increased switching frequency. Minimization of switching frequency while maintaining the lower value of load current THD requires multiple objective optimization which is achieved by optimizing a single objective function, constructed using weighting factors as a linear combination of individual objective function. The effect of weighting factor on the switching frequency minimization and the current tracking error with delay compensation for the two level voltage source inverter (VSI) are investigated in this paper. The outcomes of the predictive current control using an optimized weighting factor which is calculated using branch and bound algorithm with the delay compensation are compared with the PWM based current control scheme. The experimental tests are conducted on a 2.2 kW VSI to verify the simulation observations.

  6. Retained gas sampler extractor mixing and mass transfer rate study: Experimental and simulation results

    Energy Technology Data Exchange (ETDEWEB)

    Recknagle, K.P.; Bates, J.M.; Shekarriz, A.

    1997-11-01

    Research staff at Pacific Northwest National Laboratory conducted experimental testing and computer simulations of the impeller-stirred Retained Gas Sampler (RGS) gas extractor system. This work was performed to verify experimentally the effectiveness of the extractor at mixing viscous fluids of both Newtonian and non-Newtonian rheology representative of Hanford single- and double-shell wastes, respectively. Developing the computational models and validating their results by comparing them with experimental results would enable simulations of the mixing process for a range of fluid properties and mixing speeds. Five tests were performed with a full-scale, optically transparent model extractor to provide the data needed to compare mixing times for fluid rheology, mixer rotational direction, and mixing speed variation. The computer model was developed and exercised to simulate the tests. The tests demonstrated that rotational direction of the pitched impeller blades was not as important as fluid rheology in determining mixing time. The Newtonian fluid required at least six hours to mix at the hot cell operating speed of 3 rpm, and the non-Newtonian fluid required at least 46 hours at 3 rpm to become significantly mixed. In the non-Newtonian fluid tests, stagnant regions within the fluid sometimes required days to be fully mixed. Higher-speed (30 rpm) testing showed that the laminar mixing time was correlated to mixing speed. The tests demonstrated that, using the RGS extractor and current procedures, complete mixing of the waste samples in the hot cell should not be expected. The computer simulation of Newtonian fluid mixing gave results comparable to the test while simulation of non-Newtonian fluid mixing would require further development. In light of the laboratory test results, detailed parametric analysis of the mixing process was not performed.

  7. Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures.

    Science.gov (United States)

    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.

  8. Noninvasive surface measurement of corrosion impedance of reinforcing bar in concrete - part 1: experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jieying; Monteiro, Paulo J.M.; Morrison, H. Frank

    2000-11-01

    The corrosion state of a reinforcing steel bar in concrete can be characterized by the electrical impedance of the interface between the steel bar and the concrete. The experimental part of this study, has shown that changes in the interfacial impedance that are diagnostic of the rate and extent of the corrosion can be measured indirectly with an array of current and voltage electrodes on the concrete surface. The measured impedance, however depends on the electrical resistivity of the concrete, and the depth and diameter of the steel reinforcing bar as well as the interfacial properties. To relate the measured impedance directly to the interfacial properties, a closed-form solution to the governing Poisson's equation was developed and programmed for the potentials from arbitrary, current sources in the vicinity of the reinforcing bar. The solution uses an impedance boundary, condition for the complex impedance at the steel-concrete interface. The response of an arbitrary corrosion state can be simulated in this model by embedding the appropriate complex, frequency-dependent impedance at the interface and computing the voltage/current response that would be measured for an arbitrary placement of electrodes on the concrete surface. To simulate the experimental findings, this paper presents the modeling results by various interfacial impedances but constant concrete resistivity and constant geometry of the steel reinforcing bar This simulation confirms that important parameters of the interfacial impedance controlling corrosion kinetics such as polarization resistance and double layer capacitance are clearly, observed in the measured surface data. [References: 10

  9. Assessment of in-furnace dry sorbent injection experimental results burning low sulphur content coals

    Energy Technology Data Exchange (ETDEWEB)

    Collado, F.J. [Univ. de Zaragoza (Spain)

    1995-12-31

    In an effort to adjust the SO{sub 2} emissions of coal power stations to the current air pollutant standards, established by the EC, flue gas desulfurization tests with in-furnace dry sorbent injection technology in the Spanish coal power station ``Litoral`` (tangentially-fired) were performed. The measured retentions were lower than predicted through a one-dimensional model. Then, it was thought that a CFD 3D simulation of the injection would help to understand the complex relationships of the process. The simulation was divided in two stages: in the first one, the turbulent velocity and the temperature field were solved. In the second one, representative sorbent particles were injected in the turbulent field previously solved, the focus of this work being the global sulphur capture modeling and its validation through the experimental measurements obtained. After a revision of the models proposed in the specialized literature, a global sulfation model is chosen, being compared with the experimental data obtained in the power station. Because of the main results of this work, the authors can highlight the testing of the laboratory-scale correlations against full-scale results, and can mitigate the difficulty of estimating the actual temperature profile by experimenting with the particle and its residence time without the aid of a CFD code.

  10. Influence of a stationary magnetic field on water relations in lettuce seeds. Part II: experimental results.

    Science.gov (United States)

    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.

  11. NACA 0012 benchmark model experimental flutter results with unsteady pressure distributions

    Science.gov (United States)

    Rivera, Jose A., Jr.; Dansberry, Bryan E.; Bennett, Robert M.; Durham, Michael H.; Silva, Walter A.

    1992-01-01

    The Structural Dynamics Division at NASA Langley Research Center has started a wind tunnel activity referred to as the Benchmark Models Program. The primary objective of the program is to acquire measured dynamic instability and corresponding pressure data that will be useful for developing and evaluating aeroelastic type CFD codes currently in use or under development. The program is a multi-year activity that will involve testing of several different models to investigate various aeroelastic phenomena. This paper describes results obtained from a second wind tunnel test of the first model in the Benchmark Models Program. This first model consisted of a rigid semispan wing having a rectangular planform and a NACA 0012 airfoil shape which was mounted on a flexible two degree-of-freedom mount system. Experimental flutter boundaries and corresponding unsteady pressure distribution data acquired over two model chords located at the 60 and 95 percent span stations are presented.

  12. Experimental geothermal well at Bad Schinznach. First results; Geothermiebohrung Bad Schinznach. Erste Resultate

    Energy Technology Data Exchange (ETDEWEB)

    Haering, M.O. [Haering Geo-Project, Steinmaur (Switzerland)

    1997-12-01

    The spa of Bad Schinznach (Canton Argovia, Switzerland) endeavours to cover its heating requirements with geothermal energy. A recently drilled well to a depth of 890 meters encountered the regional acquifer of thermal water (Oberer Muschelkalk, Triassic) in three levels. Preliminary results indicate a productive aquifer in the uppermost level with a wellhead temperature of 42 C. An additional exploitation of the bottomhole formation temperature of 63 C is envisaged. (orig.) [Deutsch] Das Bad Schinznach (Kanton Aargau, Schweiz) moechte im Rahmen der wirtschaftlichen Moeglichkeiten seinen Waermebedarf mit der Nutzung des Thermalwassers aus dem Oberen Muschelkalk (Trias) decken. Eine neulich abgeteufte Bohrung bis auf 890 Meter Tiefe hat die Formation auf drei Niveaus angetroffen. Erste Resultate deuten auf ein nutzbares Vorkommen im obersten Horizont mit einer Austrittstemperatur von 42 C. Eine zusaetzliche Nutzung der hohen Formationstemperatur von 63 C auf Endtiefe wird erwogen. (orig.)

  13. Stimulating Contributions to Public Goods through Information Feedback: Some Experimental Results.

    Directory of Open Access Journals (Sweden)

    Marco A Janssen

    Full Text Available 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.

  14. Experimental and numerical results on the fluid flow driven by a traveling magnetic field

    Science.gov (United States)

    Lantzsch, R.; Galindo, V.; Grants, I.; Zhang, C.; Pätzold, O.; Gerbeth, G.; Stelter, M.

    2007-07-01

    A traveling magnetic field (TMF) driven flow and its transition from a laminar to a time-dependent flow is studied by means of ultrasonic Doppler velocimetry and numerical simulations. The experimental setup comprises a cylindrical cavity containing the electrically conducting model fluid GaInSn and a system of six equidistant coils, which are fed by an out-of-phase current to create an up- or downward directed TMF. Hence, a Lorentz force is induced in the melt which leads to meridional flow patterns. For numerical simulations commercial codes (Opera/Fidap) and a spectral code are used. The characteristic parameters of the magnetohydrodynamic model system are chosen close to the conditions used for vertical gradient freeze (VGF) crystal growth. The axisymmetric basic flow and its dependence on the dimensionless shielding parameter S are examined. It is shown that, for S>10, the flow velocity decreases significantly, whereas almost no influence is found for a smaller shielding parameter. The critical Reynolds number for the onset of instability is found in the range of 300-450. Good agreement between experimental results and the numerical simulations is achieved.

  15. Experimental and Numerical Study of Wave-Induced Long-Shore Currents on A Mild Slope Beach

    Institute of Scientific and Technical Information of China (English)

    SUN Tao; TAO Jian-hua

    2005-01-01

    The long-shore current distribution on a mild slope beach is studied by combining the numerical model and the physical experiment. The experiments of long-shore currents under the action of regular and irregular waves are conducted on mild beaches with different slopes in a wave basin. A numerical model is established, which includes a wave propagation model, a wave breaking model and a long-shore current model. The validity of the numerical model is proved by the comparison of its results with the results of the experimental model. It is concluded that the wave-induced long-shore current is influenced significantly by the incident wave height, the wave angle and the beach slope. Its application to the Bohai Bay indicates that the wave-induced currents have the same order of magnitude as the tide currents in the near-shore zone of mill slope beach. In the design of wastewater outfall locations on a mild-slope beach with shallow water of the Bohai Bay, the position of the outfall should be 10 km away from the shoreline, which is outside of the surf-zone.

  16. Experimental manifestation of the breakpoint region in the current-voltage characteristics of intrinsic Josephson junctions

    OpenAIRE

    Irie, A.; Shukrinov, Yu M.; Oya, G.

    2008-01-01

    The experimental evidence of the breakpoint on the current-voltage characteristics (IVCs) of the stacks of intrinsic Josephson junctions (IJJs) is presented. The influence of the capacitive coupling on the IVCs of Bi$_2$Sr$_2$CaCu$_2$O$_y$ IJJs has been investigated. At 4.2 K, clear breakpoint region is observed on the branches in the IVCs. It is found that the hysteresis observed on the IVC is suppressed due to the coupling compared with that expected from the McCumber parameter. Measurement...

  17. Experimental study on directional solidification of Al-Si alloys under the influence of electric currents

    Science.gov (United States)

    Räbiger, D.; Zhang, Y.; Galindo, V.; Franke, S.; Willers, B.; Eckert, S.

    2016-07-01

    The application of electric currents during solidification can cause grain refinement in metallic alloys. However, the knowledge about the mechanisms underlying the decrease in grain size remains fragmentary. This study considers the solidification of Al-Si alloys under the influence of electric currents for the configuration of two parallel electrodes at the free surface. Solidification experiments were performed under the influence of both direct currents (DC) and rectangular electric current pulses (ECP). The interaction between the applied current and its own induced magnetic field causes a Lorentz force which produces an electro-vortex flow. Numerical simulations were conducted to calculate the Lorentz force, the Joule heating and the induced melt flow. The numerical predictions were confirmed by isothermal flow measurements in eutectic GaInSn. The results demonstrate that the grain refining effect observed in our experiments can be ascribed solely to the forced melt flow driven by the Lorentz force.

  18. Experimental Investigations on PV Powered SVM-DTC Induction Motor without AC Phase Current Sensors

    Directory of Open Access Journals (Sweden)

    T. Muthamizhan

    2014-05-01

    Full Text Available The paper presents a low-cost, phase-current reconstruction algorithm for space vector modulated direct torque controlled induction motor using the information obtained from only one shunt resistor which is in series with low side switches in a conventional three-phase inverter. The aim is to develop a low-cost high - performance induction motor drive. It uses the dc-link voltage and dc current to reconstruct the stator currents needed to estimate the motor flux and the electromagnetic torque. Photovoltaic arrays convert solar power to dc electric power; uses chopper and dc-ac inverter to fed three phase Induction Motor. The chopper used here is current fed full bridge boost dc-dc converter, which is preferred and extensively used in high voltage applications and advantageous over voltage fed converters. The inverter switches are controlled by PWM techniques obtained from SVM-DTC of IM. The experimental investigations are given to prove the ability of the proposed scheme of reproducing the performances of a SVM- DTC IM drive.

  19. Safety and efficacy of transcranial direct current stimulation in acute experimental ischemic stroke.

    Science.gov (United States)

    Peruzzotti-Jametti, Luca; Cambiaghi, Marco; Bacigaluppi, Marco; Gallizioli, Mattia; Gaude, Edoardo; Mari, Silvia; Sandrone, Stefano; Cursi, Marco; Teneud, Luis; Comi, Giancarlo; Musco, Giovanna; Martino, Gianvito; Leocani, Letizia

    2013-11-01

    Transcranial direct current stimulation is emerging as a promising tool for the treatment of several neurological conditions, including cerebral ischemia. The therapeutic role of this noninvasive treatment is, however, limited to chronic phases of stroke. We thus ought to investigate whether different stimulation protocols could also be beneficial in the acute phase of experimental brain ischemia. The influence of both cathodal and anodal transcranial direct current stimulation in modifying brain metabolism of healthy mice was first tested by nuclear magnetic resonance spectroscopy. Then, mice undergoing transient proximal middle cerebral artery occlusion were randomized and treated acutely with anodal, cathodal, or sham transcranial direct current stimulation. Brain metabolism, functional outcomes, and ischemic lesion volume, as well as the inflammatory reaction and blood brain barrier functionality, were analyzed. Cathodal stimulation was able, if applied in the acute phase of stroke, to preserve cortical neurons from the ischemic damage, to reduce inflammation, and to promote a better clinical recovery compared with sham and anodal treatments. This finding was attributable to the significant decrease of cortical glutamate, as indicated by nuclear magnetic resonance spectroscopy. Conversely, anodal stimulation induced an increase in the postischemic lesion volume and augmented blood brain barrier derangement. Our data indicate that transcranial direct current stimulation exerts a measurable neuroprotective effect in the acute phase of stroke. However, its timing and polarity should be carefully identified on the base of the pathophysiological context to avoid potential harmful side effects.

  20. Experimentally determined mechanical properties of, and models for, the periodontal ligament: critical review of current literature.

    Science.gov (United States)

    Fill, Ted S; Carey, Jason P; Toogood, Roger W; Major, Paul W

    2011-01-01

    Introduction. This review is intended to highlight and discuss discrepancies in the literature of the periodontal ligament's (PDL) mechanical properties and the various experimental approaches used to measure them. Methods. Searches were performed on biomechanical and orthodontic publications (in databases: Compendex, EMBASE, MEDLINE, PubMed, ScienceDirect, and Scopus). Results. The review revealed that significant variations exist, some on the order of six orders of magnitude, in the PDL's elastic constants and mechanical properties. Possible explanations may be attributable to different experimental approaches and assumptions. Conclusions. The discrepancies highlight the need for further research into PDL properties under various clinical and experimental loading conditions. Better understanding of the PDL's biomechanical behavior under physiologic and traumatic loading conditions might enhance the understanding of the PDL's biologic reaction in health and disease. Providing a greater insight into the response of the PDL would be instrumental to orthodontists and engineers for designing more predictable, and therefore more efficacious, orthodontic appliances.

  1. Experimental Determination of DT Yield in High Current DD Dense Plasma Focii

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, D. R. [National Security Technologies, LLC; Hagen, E. C. [National Security Technologies, LLC; Meehan, B. T. [National Security Technologies, LLC; Springs, R. K. [University of Nevada, Las Vegas; O' Brien, R. J. [University of Nevada, Las Vegas

    2013-06-18

    Dense Plasma Focii (DPF), which utilize deuterium gas to produce 2.45 MeV neutrons, may in fact also produce DT fusion neutrons at 14.1 MeV due to the triton production in the DD reaction. If beam-target fusion is the primary producer of fusion neutrons in DPFs, it is possible that ejected tritons from the first pinch will interact with the second pinch, and so forth. The 2 MJ DPF at National Security Technologies’ Losee Road Facility is able to, and has produced, over 1E12 DD neutrons per pulse, allowing an accurate measurement of the DT/DD ratio. The DT/DD ratio was experimentally verified by using the (n,2n) reaction in a large piece of praseodymium metal, which has a threshold reaction of 8 MeV, and is widely used as a DT yield measurement system1. The DT/DD ratio was experimentally determined for over 100 shots, and then compared to independent variables such as tube pressure, number of pinches per shot, total current, pinch current and charge voltage.

  2. Experimental demonstration of a new radiation mechanism: emission by an oscillating, accelerated, superluminal polarization current

    CERN Document Server

    Ardavan, A; Ardavan, H; Fopma, J; Halliday, D; Hayes, W

    2004-01-01

    We describe the experimental implementation of a superluminal ({\\it i.e.} faster than light {\\it in vacuo}) polarization current distribution that both oscillates and undergoes centripetal acceleration. Theoretical treatments lead one to expect that the radiation emitted from each volume element of such a polarization current will comprise a \\v{C}erenkov-like envelope with two sheets that meet along a cusp. The emission from the experimental machine is in good agreement with these expectations, the combined effect of the volume elements leading to tightly-defined beams of a well-defined geometry, determined by the source speed and trajectory. In addition, over a restricted range of angles, we detect the presence of cusps in the emitted radiation. These are due to the detection over a short time period (in the laboratory frame) of radiation emitted over a considerably longer period of source time. Consequently, the intensity of the radiation at these angles was observed to decline more slowly with increasing d...

  3. Prediction of SFL Interruption Performance from the Results of Arc Simulation during High-Current Phase

    Science.gov (United States)

    Lee, Jong-Chul; Lee, Won-Ho; Kim, Woun-Jea

    2015-09-01

    The design and development procedures of SF6 gas circuit breakers are still largely based on trial and error through testing although the development costs go higher every year. The computation cannot cover the testing satisfactorily because all the real processes arc not taken into account. But the knowledge of the arc behavior and the prediction of the thermal-flow inside the interrupters by numerical simulations are more useful than those by experiments due to the difficulties to obtain physical quantities experimentally and the reduction of computational costs in recent years. In this paper, in order to get further information into the interruption process of a SF6 self-blast interrupter, which is based on a combination of thermal expansion and the arc rotation principle, gas flow simulations with a CFD-arc modeling are performed during the whole switching process such as high-current period, pre-current zero period, and current-zero period. Through the complete work, the pressure-rise and the ramp of the pressure inside the chamber before current zero as well as the post-arc current after current zero should be a good criterion to predict the short-line fault interruption performance of interrupters.

  4. A study of experimental evaluations of neural network learning algorithms: current research practice

    OpenAIRE

    Prechelt, Lutz

    2007-01-01

    113 articles about neural network learning algorithms published in 1993 and 1994 are examined for the amount of experimental evaluation they contain. Every third of them does employ not even a single realistic or real learning problem. Only 6% of all articles present results for more than one problem using real world data.Furthermore, one third of all articles does not present any quantitative comparison with a previously known algorithm. These results indicate that the q...

  5. Complementary numerical–experimental benchmarking for shape optimization and validation of structures subjected to wave and current forces

    DEFF Research Database (Denmark)

    Markus, D.; Ferri, Francesco; Wüchner, R.

    2015-01-01

    that focuses on differences in load curves resulting from 2D and 3D flows. It is shown that the major trends predicted by the numerical simulations are also captured in the experiment, highlighting the potential of CFD as a powerful tool for shape optimization studies. The overall aim of the paper...... variations of the structure on the resulting horizontal forces. Steady current conditions, dynamic loading due to waves, and combined wave–current scenarios are considered. A clear focus is put on simplicity and reproducibility, allowing for efficient testing of related methods and codes. This is achieved...... by defining a simple test geometry, altered in one design variable only, and by designing the test case such that a two dimensional analysis of the flow fields is possible. The force sensitivities to changes in the geometry are determined both numerically and experimentally for a great bandwidth of different...

  6. Test results of 12/18 kA ReBCO coated conductor current leads

    Science.gov (United States)

    Kovalev, I. A.; Surin, M. I.; Naumov, A. V.; Novikov, M. S.; Novikov, S. I.; Ilin, A. A.; Polyakov, A. V.; Scherbakov, V. I.; Shutova, D. I.

    2017-07-01

    A pair of hybrid current leads (brass + stacked & soldered ReBCO tapes) rated for 12 kA in steady state and for up to 18 kA at pulsed over current conditions was designed, developed and tested at NRC ;Kurchatov Institute; (NRC ;KI;). During the experiment at LN2 temperature, the current leads (CLs) were successfully charged with 18 kA at 100 A/s ramp rate. To date, as far as we know, this is the highest current capacity achieved for 2G HTS current leads. The feasibility of ;stack-and-soldering technique; for 10 kA+ class coated conductor CLs for accelerators and fusion was demonstrated. This paper gives an overview of the leads design and presents the preliminary test results. Detailed studies of magnetic properties and current sharing process for the stacked and staggered HTS joints are also reported.

  7. Clinical and experimental studies on polyherbal formulations for diabetes:current status and future prospective

    Institute of Scientific and Technical Information of China (English)

    Ahmad Ghorbani

    2014-01-01

    Diabetes is a leading cause of morbidity and mortality in the world. There is currently an active search for antidiabetic drugs with greater effectiveness with fewer and less adverse side effects. Although numerous individual herbs have been experimentally or clinically reported to possess antidiabetic effects, considerably less research has been conducted on polyherbal compounds. It is believed that herbal compounds containing multiple plant products have synergistic antidiabetic effects and could enhance the desired actions. Several polyherbal formulations have been studied as therapeutic agents in diabetes management. To describe the current state of research on polyherbal compounds in the treatment of diabetes, an extensive review of literature was undertaken on several major databases. This paper presents what is known about the efifcacy of these polyherbal formulations and compare their antidiabetic effects with those of current oral hypoglycemic drugs as reference. The percent decrease in blood glucose, lipids and other biochemical parameters achieved by each product in diabetic animals and patients is reported. Also, the possible mechanisms responsible for hypoglycemic action of polyherbal formulations are discussed.

  8. Minimum quench power dissipation and current non-uniformity in international thermonuclear experimental reactor type NbTi cable-in-conduit conductor samples under direct current conditions

    Science.gov (United States)

    Rolando, G.; van Lanen, E. P. A.; Nijhuis, A.

    2012-05-01

    The level of current non-uniformity in NbTi cable-in-conduit conductors (CICCs) sections near the joints in combination with the magnetic field profile needs attention in view of proper joint design. The strand joule power and current distribution at quench under DC conditions of two samples of ITER poloidal field coil conductors, as tested in the SULTAN facility, and of the so called PFCI model coil insert, have been analyzed with the numerical cable model JackPot. The precise trajectories of all individual strands, joint design, cabling configuration, spatial distribution of the magnetic field, sample geometry, and experimentally determined interstrand resistance distributions have been taken into account. Although unable to predict the quench point due to the lack of a thermal-hydraulic routine, the model allows to assess the instantaneous strand power at quench and its local distribution in the cable once the quench conditions in terms of current and temperature are experimentally known. The analysis points out the relation of the above mentioned factors with the DC quench stability of both short samples and coils. The possible small scale and local electrical-thermal interactions were ignored in order to examine the relevance of such effects in the overall prediction of the CICC performance. The electromagnetic code shows an excellent quantitative predictive potential for CICC transport properties, excluding any freedom for matching the results. The influence of the local thermal effects in the modeling is identified as being marginal and far less than the generally accepted temperature margin for safe operation.

  9. Are current disease-modifying therapeutics in multiple sclerosis justified on the basis of studies in experimental autoimmune encephalomyelitis?

    Science.gov (United States)

    Farooqi, Nasr; Gran, Bruno; Constantinescu, Cris S

    2010-11-01

    The precise aetio-pathology of multiple sclerosis remains elusive. However, important recent advances have been made and several therapies have been licensed for clinical use. Many of these were developed, validated or tested in the animal model, experimental autoimmune encephalomyelitis (EAE). This systematic review aims to assess whether the current disease modifying treatments and those that are the closest to the clinic are justified on the basis of the results of EAE studies. We discuss some aspects of the utility and caveats of EAE as a model for multiple sclerosis drug development.

  10. Numerical simulation and experimental study of the hydrodynamics of a modeled reef located within a current

    Institute of Scientific and Technical Information of China (English)

    姜昭阳; 梁振林; 唐衍力; 黄六一; 于定勇; 姜曼松

    2010-01-01

    The hydrodynamic forces and flow field of artificial reef models in steady flow were numerically investigated using the RNG k–εturbulent model.The numerical simulation results are consistent with results observed by experimental means.A comparative study indicates that the corresponding errors of forces between calculated values and values observed in the experiment vary in the range of 2.3%–11.2%and that the corresponding errors of velocities vary in the range of 1.3%–15.8%. The flow field numerical result...

  11. Removal of arsenic from wastewaters by cryptocrystalline magnesite: complimenting experimental results with modelling

    CSIR Research Space (South Africa)

    Masindi, Vhahangwele

    2016-02-01

    Full Text Available -1 Journal of Cleaner Production Removal of arsenic from wastewaters by cryptocrystalline magnesite: complimenting experimental results with modelling Vhahangwele Masindi W. Mugera Gitari Keywords: Arsenic Mine leachates Cryptocrystalline...

  12. ANALYS OF EXPERIMENTAL HYBRID CAR TESTING RESULTS ON URBAN DRIVING CYCLE

    Directory of Open Access Journals (Sweden)

    S. Serikov

    2014-02-01

    Full Text Available The experimental hybrid car testing results are presented. The estimation of hybrid car draft-speed characteristics, energy and ecological indicators on urban driving cycle are given.

  13. Experimental and modelling results of a parallel-plate based active magnetic regenerator

    DEFF Research Database (Denmark)

    Tura, A.; Nielsen, Kaspar Kirstein; Rowe, A.

    2012-01-01

    The performance of a permanent magnet magnetic refrigerator (PMMR) using gadolinium parallel plates is described. The configuration and operating parameters are described in detail. Experimental results are compared to simulations using an established twodimensional model of an active magnetic...

  14. Experimental pain processing in individuals with cognitive impairment: current state of the science.

    Science.gov (United States)

    Defrin, Ruth; Amanzio, Martina; de Tommaso, Marina; Dimova, Violeta; Filipovic, Sasa; Finn, David P; Gimenez-Llort, Lydia; Invitto, Sara; Jensen-Dahm, Christina; Lautenbacher, Stefan; Oosterman, Joukje M; Petrini, Laura; Pick, Chaim G; Pickering, Gisele; Vase, Lene; Kunz, Miriam

    2015-08-01

    Cognitive impairment (CI) can develop during the course of ageing and is a feature of many neurological and neurodegenerative diseases. Many individuals with CI have substantial, sustained, and complex health care needs, which frequently include pain. However, individuals with CI can have difficulty communicating the features of their pain to others, which in turn presents a significant challenge for effective diagnosis and treatment of their pain. Herein, we review the literature on responsivity of individuals with CI to experimental pain stimuli. We discuss pain responding across a large number of neurological and neurodegenerative disorders in which CI is typically present. Overall, the existing data suggest that pain processing is altered in most individuals with CI compared with cognitively intact matched controls. The precise nature of these alterations varies with the type of CI (or associated clinical condition) and may also depend on the type of pain stimulation used and the type of pain responses assessed. Nevertheless, it is clear that regardless of the etiology of CI, patients do feel noxious stimuli, with more evidence for hypersensitivity than hyposensitivity to these stimuli compared with cognitively unimpaired individuals. Our current understanding of the neurobiological mechanisms underpinning these alterations is limited but may be enhanced through the use of animal models of CI, which also exhibit alterations in nociceptive responding. Further research using additional behavioural indices of pain is warranted. Increased understanding of altered experimental pain processing in CI will facilitate the development of improved diagnostic and therapeutic approaches for pain in individuals with CI.

  15. Analytical magnetic torque calculations and experimental testing of radial flux permanent magnet-type eddy current brakes

    Science.gov (United States)

    Choi, Jang-Young; Jang, Seok-Myeong

    2012-04-01

    This paper reports on analytical magnetic torque calculations and experimental tests of a radial flux permanent magnet (RFPM)-type eddy current brake (ECB). Analytical solutions for permanent magnet-generated magnetic fields that consider the eddy current reaction are obtained by using a magnetic vector potential and a two dimensional (2D) polar coordinate system. On the basis of these solutions, the analytical expressions for a magnetic torque are also derived. All analytical results are validated extensively by non-linear finite element calculations. In particular, magnetic torque measurements are obtained in tests to confirm the analyses. Finally, practical issues related to the analytical study of RFPM-type ECBs are fully discussed.

  16. Flashover Measurement On A Solar Array- Results of EMAGS3 Experimental Campaign

    Science.gov (United States)

    Inguimbert, V.; Sarrailh, P.; Sarrail, D.; Baur, C.; Payan, D.; Gerhard, A.; Boulanger, B.; Pelissou, P.; Wuersching, C.

    2011-10-01

    This paper describes the results obtained during the experimental campaign conducted in the frame of the ESA EMAGS3 project "Flash-over evaluation on large solar panels". The objective of this experimental campaign was to understand the characteristics of the so-called flash-over phenomenon. Therefore, a real solar panel has been tested in a large vacuum chamber under representative conditions. The results of the conducted experiments as well as the modelling of the data are presented.

  17. Experimental study on bed-load sediment transport under irregular wave and current combined flow

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using an irregularly oscillating tray and flume, a series of experiments are completed to evaluate bed-load sediment transport rate under irregular wave- current coexistent fild. Testing conditions include three interaction angles 0°, 45°, 90° and two kinds of median sizes (0.38 and 1.10 mm).The results of transport rate show that the net sediment transport rate can be expressed approximately as the function of the maximum bottom shear stress of waves, mean shear stress of current and the grain size.

  18. Experimental and theoretical analysis of an optical current sensor for high power systems

    Science.gov (United States)

    Brigida, A. C. S.; Nascimento, I. M.; Mendonça, S.; Costa, J. C. W. A.; Martinez, M. A. G.; Baptista, J. M.; Jorge, P. A. S.

    2013-03-01

    A magneto-optical sensor, using a dual quadrature polarimetric processing scheme, was evaluated for current metering and protection applications in high voltage lines. Sensor calibration and resolution were obtained in different operational conditions using illumination in the 1550-nm band. Results obtained indicated the feasibility of interrogating such sensor via the optical ground wire (OPGW) link installed in standard high power grids. The polarimetric bulk optical current sensor also was theoretically studied, and the effects of different sources of error considering practical deployment were evaluated. In particular, the interference from external magnetic fields in a tree-phase system was analyzed.

  19. Synthesizing large-scale pyroclastic flows: Experimental design, scaling, and first results from PELE

    Science.gov (United States)

    Lube, G.; Breard, E. C. P.; Cronin, S. J.; Jones, J.

    2015-03-01

    Pyroclastic flow eruption large-scale experiment (PELE) is a large-scale facility for experimental studies of pyroclastic density currents (PDCs). It is used to generate high-energy currents involving 500-6500 m3 natural volcanic material and air that achieve velocities of 7-30 m s-1, flow thicknesses of 2-4.5 m, and runouts of >35 m. The experimental PDCs are synthesized by a controlled "eruption column collapse" of ash-lapilli suspensions onto an instrumented channel. The first set of experiments are documented here and used to elucidate the main flow regimes that influence PDC dynamic structure. Four phases are identified: (1) mixture acceleration during eruption column collapse, (2) column-slope impact, (3) PDC generation, and (4) ash cloud diffusion. The currents produced are fully turbulent flows and scale well to natural PDCs including small to large scales of turbulent transport. PELE is capable of generating short, pulsed, and sustained currents over periods of several tens of seconds, and dilute surge-like PDCs through to highly concentrated pyroclastic flow-like currents. The surge-like variants develop a basal surge (1.5-3 m thick) with 100 to 10-4 vol % particles. Their deposits include stratified, massive, normally and reversely graded beds, lobate fronts, and laterally extensive veneer facies beyond channel margins.

  20. Experimental results on rock resistivity and its applications in monitoring and predicting natural disasters

    Science.gov (United States)

    Zhou, Jianguo; Zhu, Tao; Tang, Baolin

    2017-04-01

    There have been many earthquakes occurring in Chinese Mainland. These earthquakes, especially large earthquakes, often cause immeasurable loss. For instance, the 2008 Wenchuan Ms8.0 earthquake killed 70, 000 people and caused 17, 000 people missing. It is well known that this earthquake was not predicted. Why? Were there no precursors? After analyzing the geo-electrical resistivity recording at Chengdu station which is only about 36 km to the epicenter, we find that resistivity had changed abnormally very significantly along NE direction but no outstanding abnormal changes had been observed along NW direction before the earthquake. Perhaps this non-consistent changes result in that this earthquake was not predicted. However, in another standpoint, can another observation way be found to supplement the current geo-electrical resistivity observation in Chinese Mainland in order to improve the probability of catching the precursor? This motivates us to conduct experiments in lab and field. Apparent resistivity data are acquired along three common-midpoint measuring lines during the fixed-rate uniaxial compression on two sets of dry man-made samples and a Magnetite sample. We construct the relative resistivity change images (RRCIs). Our results indicate that all RRCIs show a trending change with stress: with the increase of stress, the resistivity-decreased region (RDR) in the RRCIs shrinks/expands, while the resistivity-increased region (RIR) expands/shrinks gradually, which is in agreement with the field experimental results of earthquake monitoring (Feng et al., 2001). Our results encourage us to conclude that the trending changes in RRCI with stress could probably become a useful indicator in monitoring and predicting earthquakes, volcanic eruptions and large-scale geologic movements. This work is supported by National Natural Science Foundation of China (NSFC, Grant 41574083).

  1. Experimental determination of two-dimensional critical current density distribution in YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, Naoyuki; Shinkai, Yoshichika [Faculty of Engineering, Yokohama National University, Tokiwadai, Hodogaya, Yokohama (Japan); Iijima, Yasuhiro; Kakimoto, Kazuomi; Takeda, Kaoru [Materials Research Laboratory, Fujikura Ltd., Kiba, Koto, Tokyo (Japan)

    2001-08-01

    The critical current density (J{sub c}) distribution in YBCO coated conductors is attracting interest from the viewpoint of its influence on their AC loss characteristics as well as from material science and process engineering. A two-dimensional J{sub c} distribution in a YBCO coated conductor made by the IBAD (ion-beam assisted deposition) and the PLD (pulse-laser deposition) method can be determined by the magnetic-knife method with spatial resolutions of 0.2 mm lateral and 10 mm longitudinal directions, respectively. In an up-to-date 80A-class YBCO coated conductor, the J{sub c} is relatively uniform in the central part and reaches mbox{l_brace}7$x$10{sup 9} A m{sup -2}, {r_brace} while the J{sub c} fluctuates spatially in the central part of a tape fabricated earlier and with less critical current. Near the edges of the tapes, the J{sub c} is higher or lower than in the central part and the experimentally determined J{sub c} distributions are far from uniform. This suggests that a presumption of a uniform J{sub c} for AC loss estimations is not always reasonable and can lead to a large error in the estimated AC losses. (author)

  2. Experimental and numerical assessment of low-frequency current distributions from UMTS and GSM mobile phones.

    Science.gov (United States)

    Gosselin, Marie-Christine; Kühn, Sven; Kuster, Niels

    2013-12-07

    The evaluation of the exposure from mobile communication devices requires consideration of electromagnetic fields (EMFs) over a broad frequency range from dc to GHz. Mobile phones in operation have prominent spectral components in the low-frequency (LF) and radio-frequency (RF) ranges. While the exposure to RF fields from mobile phones has been comprehensively assessed in the past, the LF fields have received much less attention. In this study, LF fields from mobile phones are assessed experimentally and numerically for the global system for mobile (GSM) and universal mobile telecommunications system (UMTS) communication systems and conclusions about the global (LF and RF) EMF exposure from both systems are drawn. From the measurements of the time-domain magnetic fields, it was found that the contribution from the audio signal at a normal speech level, i.e., -16 dBm0, is the same order of magnitude as the fields induced by the current bursts generated from the implementation of the GSM communication system at maximum RF output level. The B-field induced by currents in phones using the UMTS is two orders of magnitude lower than that induced by GSM. Knowing that the RF exposure from the UMTS is also two orders of magnitude lower than from GSM, it is now possible to state that there is an overall reduction of the exposure from this communication system.

  3. Experimental diabetes induced by alloxan and streptozotocin: The current state of the art.

    Science.gov (United States)

    Radenković, Miroslav; Stojanović, Marko; Prostran, Milica

    2016-01-01

    Diabetes mellitus is a chronic metabolic disorder with a high prevalence worldwide. Animal models of diabetes represent an important tool in diabetes investigation that helps us to avoid unnecessary and ethically challenging studies in human subjects, as well as to obtain a comprehensive scientific viewpoint of this disease. Although there are several methods through which diabetes can be induced, chemical methods of alloxan- and streptozotocin-induced diabetes represent the most important and highly preferable experimental models for this pathological condition. Therefore, the aim of this article was to review the current knowledge related to quoted models of diabetes, including to this point available information about mechanism of action, particular time- and dose-dependent protocols, frequent problems, as well as major limitations linked to laboratory application of alloxan and sterptozotocin in inducing diabetes. Given that diabetes is known to be closely associated with serious health consequences it is of fundamental importance that current animal models for induction of diabetes should be continuously upgraded in order to improve overall prevention, diagnosis and treatment of this pathological condition.

  4. MEASURING RESULTS NUMERAL TREATMENT OF IMPULSIVE CURRENTS BY MEANS OF ROGOVSKY BELT APPLICATION

    Directory of Open Access Journals (Sweden)

    U. Batygin

    2009-01-01

    Full Text Available The technique of numerical processing of measurement results of pulse currents by means of Rogovsky belt application is offered in the given work. It is shown that at measurement of signals by digital oscillographs and further numerical transformation of target signals, the possibilities of Rogovsky belt without the application of additional devices that in turn allows to define parameters of pulse currents with any peak-time characteristics essentially expand.

  5. First Experimental Results Using Sparse Aperture Mask for Low Order Wavefront Sensing

    Science.gov (United States)

    Subedi, Hari; Zimmerman, Neil T.; Kasdin, N. Jeremy; Eldorado Riggs, A. J.

    2016-01-01

    We can determine the existence of life outside of earth by analyzing the spectra of exoplanets. Such direct imaging will provide the capability to thoroughly characterize an exoplanet's atmosphere. Direct imaging of exoplanets, however, has many technical challenges and difficulties: scattering and diffraction of light and the large difference in contrast, which is the ratio of brightness between the bright star and the dimmer planet. A coronagraph is an optical device that manipulates the diffraction of starlight and creates a region of high contrast (dark hole) where the dimmer planets can be seen. While in principle the level of contrast required for direct imaging of exoplanets can be achieved by stellar coronagraphic imaging, the resulting dark hole is highly sensitive to phase aberrations. In order to effectively suppress starlight for exoplanet imaging applications, low-order wavefront aberrations entering a coronagraph such as tip-tilt, defocus and coma must be determined and compensated for. A sparse-aperture mask (SAM) can be integrated in the telescopic imaging system to make precise estimate of low-order wavefront aberrations. In this technique, the starlight rejected by the coronagraph's focal plane stop is collimated to a relay pupil, where the mask forms an interference fringe pattern on a detector and the phase aberrations are inferred from this fringe pattern. At Princeton's High Contrast Imaging Lab (HCIL), we have numerically proved this concept and we are currently working on verifying it experimentally.

  6. Transcranial direct-current stimulation induced in stroke patients with aphasia: a prospective experimental cohort study

    Directory of Open Access Journals (Sweden)

    Michele Devido Santos

    Full Text Available CONTEXT AND OBJECTIVE: Previous animal and human studies have shown that transcranial direct current stimulation can induce significant and lasting neuroplasticity and may improve language recovery in patients with aphasia. The objective of the study was to describe a cohort of patients with aphasia after stroke who were treated with transcranial direct current stimulation. DESIGN AND SETTING: Prospective cohort study developed in a public university hospital. METHODS: Nineteen patients with chronic aphasia received 10 transcranial direct current stimulation sessions lasting 20 minutes each on consecutive days, using a current of 2 mA. The anode was positioned over the supraorbital area and the cathode over the contralateral motor cortex. The following variables were analyzed before and after the 10 neuromodulation sessions: oral language comprehension, copying, dictation, reading, writing, naming and verbal fluency. RESULTS: There were no adverse effects in the study. We found statistically significant differences from before to after stimulation in relation to simple sentence comprehension (P = 0.034, naming (P = 0.041 and verbal fluency for names of animals (P = 0.038. Improved scores for performing these three tasks were seen after stimulation. CONCLUSIONS: We observed that excitability of the primary motor cortex through transcranial direct current stimulation was associated with effects on different aspects of language. This can contribute towards future testing in randomized controlled trials.

  7. Qualitative comparisons of experimental results on deterministic freak wave generation based on modulational instability

    CERN Document Server

    Karjanto, N

    2016-01-01

    A number of qualitative comparisons of experimental results on unidirectional freak wave generation in a hydrodynamic laboratory are presented in this paper. A nonlinear dispersive type of wave equation, the nonlinear Schr\\"{o}dinger equation, is chosen as the theoretical model. A family of exact solutions of this equation the so-called Soliton on Finite Background describing modulational instability phenomenon is implemented in the experiments. It is observed that all experimental results show an amplitude increase according to the phenomenon. Both the carrier wave frequency and the modulation period are preserved during the wave propagation. As predicted by the theoretical model, a phase singularity is also observed in the experiments. Due to frequency downshift phenomenon, the experimental signal and spectrum lose their symmetric property. Another qualitative comparison indicates that the Wessel curves for the experimental results are the perturbed version of the theoretical ones.

  8. Overview of HIT-SI3 experiment: Simulations, Diagnostics, and Summary of Current Results

    Science.gov (United States)

    Penna, James; Jarboe, Thomas; Nelson, Brian; Hossack, Aaron; Sutherland, Derek; Morgan, Kyle; Hansen, Chris; Benedett, Thomas; Everson, Chris; Victor, Brian

    2016-10-01

    The Helicity Injected Torus - Steady Inductive 3(HIT-SI3)experiment forms and maintains spheromaks via Steady Inductive Helicity Injection (SIHI). Three injector units allow for continuous injection of helicity into a copper flux conserver in order to sustain a spheromak. Firing of the injectors with a phase difference allows finite rotation of the plasma to provide a stabilizing effect. Simulations in the MHD code NIMROD and the fluid-model code PSI-TET provide validation and a basis for interpretation of the observed experimental data. Thompson Scattering (TS) and Far Infrared (FIR) Interferometer systems allow temperature and line-averaged density measurements to be taken. An Ion Doppler Spectroscopy (IDS) system allows measurement of the plasma rotation and velocity. HIT-SI3 data has been used for validation of IDCD predictions, in particular the projected impedance of helicity injectors according to the theory. The experimental impedances have been calculated here for the first time for different HIT-SI3 regimes. Such experimental evidence will contribute to the design of future experiments employing IDCD as a current-drive mechanism. Work supported by the D.O.E., Office of Science, Office of Fusion Science.

  9. Calcification in Chronically-Implanted Blood Pumps: Experimental Results and Review of the Literature

    OpenAIRE

    Turner, Stephen A.; Bossart, Mattie I.; Milam, John D.; Fuqua, John M.; Igo, Stephen R.; McGee, Michael G.; Frazier, O. Howard

    1982-01-01

    Blood compatibility is a major objective in the development of long-term, implantable circulatory assist (left ventricular assist devices) and replacement (total artificial heart) devices. An important problem in experimental studies in animals has been the propensity for calcification to occur at the blood/material interface. Presented is a summary of our experience (27 studies) with blood pump calcification and a review of the current literature regarding this complication.

  10. Comparison of experimental and theoretical reaction rail currents, rail voltages, and airgap fields for the linear induction motor research vehicle

    Science.gov (United States)

    Elliott, D. G.

    1977-01-01

    Measurements of reaction rail currents, reaction rail voltages, and airgap magnetic fields in tests of the Linear Induction Motor Research Vehicle (LIMRV) were compared with theoretical calculations from the mesh/matrix theory. It was found that the rail currents and magnetic fields predicted by the theory are within 20 percent of the measured currents and fields at most motor locations in most of the runs, but differ by as much as a factor of two in some cases. The most consistent difference is a higher experimental than theoretical magnetic field near the entrance of the motor and a lower experimental than theoretical magnetic field near the exit. The observed differences between the theoretical and experimental magnetic fields and currents do not account for the differences of as much as 26 percent between the theoretical and experimental thrusts.

  11. Prior doctor shopping resulting from differential treatment correlates with differences in current patient-provider relationships.

    Science.gov (United States)

    Gudzune, Kimberly A; Bennett, Wendy L; Cooper, Lisa A; Clark, Jeanne M; Bleich, Sara N

    2014-09-01

    To determine the prevalence of doctor shopping resulting from differential treatment and to examine associations between this shopping and current primary care relationships. In 2012, a national internet-based survey of 600 adults receiving primary care in the past year with a BMI ≥ 25 kg/m(2) was conducted. Our independent variable was "switching doctors because I felt treated differently because of my weight." Logistic regression models to examine the association of prior doctor shopping with characteristics of current primary care relationships: duration, trust in primary care provider (PCP), and perceived PCP weight-related judgment, adjusted for patient factors were used. Overall, 13% of adults with overweight/obesity reported previously doctor shopping resulting from differential treatment. Prior shoppers were more likely to report shorter durations of their current relationships [73% vs. 52%; p = 0.01] or perceive that their current PCP judged them because of their weight [74% vs. 11%; p shop resulting from perceived differential treatment. These prior negative experiences have no association with trust in current relationships, but our results suggest that patients may remain sensitive to provider weight bias. © 2014 The Obesity Society.

  12. Current methods of the modeling of experimental diabetes mellitus type 2: a literature review

    Directory of Open Access Journals (Sweden)

    Yu. M. Kolesnyk

    2016-01-01

    Full Text Available Background. Diabetes mellitus (DM became a major problem of the healthcare in Ukraine. The rapid increase in the incidence was noticed especially in recent decade. The treatment of diabetes and its complications become a difficult task. From this standpoint the experimental modeling of diabetes is rather essential. Using the experimental models gives the possibility to assess the significance of the activity of pharmacological substances or to find out new mechanism in the action of medicaments. The aim of this review is to light up the most studied and common experimental models of diabetes mellitus type 2 (T2DM in small rodents and find out their drawbacks. It is known the background of T2DM is the violation of the insulin homeostasis such as the resistance of peripheral tissues to insulin as well as the dysfunction of the pancreatic beta-cells, which both lead to appearance of such phenomena as the glucosetoxicity and the lipotoxicity. In the end they both could result in life threatening vascular complications. Considering the steady growth of T2DM patients, the development both of the drug and non-drug methods of its treatment with the high therapeutically efficiency and the perfect safety profile becomes essential. The most important stage of the search of new ways of influence on pathogenetic links of T2DM is the preclinical stage. From this standpoint the usage of experimental models of T2DM has a huge importance. There are a lot of models of T2DM developed by different scientists. These models could be spontaneous or be induced by different chemical diabetogenic substances, diet or surgical interventions or be a combination of methods listed above. Conclusions. We should underline the adequate modeling of DM2T is the necessary basis for the pre-clinical study of drug-based and not-drug methods of correction of the hyperglycemic states. Using different models makes it possible for infer the obtained experimental results to the society

  13. They see a rat, we seek a cure for diseases: the current status of animal experimentation in medical practice.

    Science.gov (United States)

    Kehinde, Elijah O

    2013-01-01

    The objective of this review article was to examine current and prospective developments in the scientific use of laboratory animals, and to find out whether or not there are still valid scientific benefits of and justification for animal experimentation. The PubMed and Web of Science databases were searched using the following key words: animal models, basic research, pharmaceutical research, toxicity testing, experimental surgery, surgical simulation, ethics, animal welfare, benign, malignant diseases. Important relevant reviews, original articles and references from 1970 to 2012 were reviewed for data on the use of experimental animals in the study of diseases. The use of laboratory animals in scientific research continues to generate intense public debate. Their use can be justified today in the following areas of research: basic scientific research, use of animals as models for human diseases, pharmaceutical research and development, toxicity testing and teaching of new surgical techniques. This is because there are inherent limitations in the use of alternatives such as in vitro studies, human clinical trials or computer simulation. However, there are problems of transferability of results obtained from animal research to humans. Efforts are on-going to find suitable alternatives to animal experimentation like cell and tissue culture and computer simulation. For the foreseeable future, it would appear that to enable scientists to have a more precise understanding of human disease, including its diagnosis, prognosis and therapeutic intervention, there will still be enough grounds to advocate animal experimentation. However, efforts must continue to minimize or eliminate the need for animal testing in scientific research as soon as possible. © 2013 S. Karger AG, Basel.

  14. Analysis and presentation of experimental results with examples, problems and programs

    CERN Document Server

    Christodoulides, Costas

    2017-01-01

    This book is intended as a guide to the analysis and presentation of experimental results. It develops various techniques for the numerical processing of experimental data, using basic statistical methods and the theory of errors. After presenting basic theoretical concepts, the book describes the methods by which the results can be presented, both numerically and graphically. The book is divided into three parts, of roughly equal length, addressing the theory, the analysis of data, and the presentation of results. Examples are given and problems are solved using the Excel, Origin, Python and R software packages. In addition, programs in all four languages are made available to readers, allowing them to use them in analyzing and presenting the results of their own experiments. Subjects are treated at a level appropriate for undergraduate students in the natural sciences, but this book should also appeal to anyone whose work involves dealing with experimental results.

  15. Monitoring tooth profile faults in epicyclic gearboxes using synchronously averaged motor currents: Mathematical modeling and experimental validation

    Science.gov (United States)

    Ottewill, J. R.; Ruszczyk, A.; Broda, D.

    2017-02-01

    Time-varying transmission paths and inaccessibility can increase the difficulty in both acquiring and processing vibration signals for the purpose of monitoring epicyclic gearboxes. Recent work has shown that the synchronous signal averaging approach may be applied to measured motor currents in order to diagnose tooth faults in parallel shaft gearboxes. In this paper we further develop the approach, so that it may also be applied to monitor tooth faults in epicyclic gearboxes. A low-degree-of-freedom model of an epicyclic gearbox which incorporates the possibility of simulating tooth faults, as well as any subsequent tooth contact loss due to these faults, is introduced. By combining this model with a simple space-phasor model of an induction motor it is possible to show that, in theory, tooth faults in epicyclic gearboxes may be identified from motor currents. Applying the synchronous averaging approach to experimentally recorded motor currents and angular displacements recorded from a shaft mounted encoder, validate this finding. Comparison between experiments and theory highlight the influence of operating conditions, backlash and shaft couplings on the transient response excited in the currents by the tooth fault. The results obtained suggest that the method may be a viable alternative or complement to more traditional methods for monitoring gearboxes. However, general observations also indicate that further investigations into the sensitivity and robustness of the method would be beneficial.

  16. Survey of Current Experimental Studies of Effects of Traditional Chinese Medicine on Peripheral Nerve Regeneration

    Institute of Scientific and Technical Information of China (English)

    WU Qun-li; LIANG Xiao-chun

    2006-01-01

    The repairing and regeneration of peripheral nerves is a very complex biological and cytological process, its mechanism is unclear so far, and thus results in the lack of specific and effectual therapy and medicament. Chinese herbs and their effective components have their own inimitable predominance in promoting peripheral nerve regeneration, such as their multi-factorial, multi-target and multi-functional action, abundant source, inexpensive, etc. In this paper, the experimental studies reported in recent 5 years concerning the effects of Chinese herbs or their active components on peripheral nerve repairing and regeneration are reviewed in respects of the integral level, cellular level, molecular level and gene level.

  17. An experimental study on counter current flow limitation in annular narrow gaps with large diameter

    Energy Technology Data Exchange (ETDEWEB)

    Park, Rae Joon; Jeong, Ji Whan; Lee, Sung Jin; Cho, Young Ro; Ha, Kwang Sun; Kim, Sang Baik; Kim, Hee Dong [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-04-01

    The present study intends to carry out CCFL experiment with the same gap size as the CHFG facility and suggest an empirical correlation in order to provide basic information useful to development of an empirical critical-power correlation. The present facility consists of water accumulator tank, test section, DC pump, air regulator, valves and sensors. Air and water are used as working fluids. The experiments are carried out at the atmospheric pressure. Differential pressure between the gap ends, liquid and gas phase flow rates, temperature, lower plenum pressure are measured.Measured values are expressed in terms of Wallis' parameter using gap size as a characteristic length. There is a big difference between the present experimental results and the Koizumi et al.'s results, but the present experimental results are very similar to the Richter et al.'s results. The present results agree well with the Osakabe and Kawasaki's results. In comparison of present experiments with the Koizumi et al.'s experiments, gap thickness is similar, but the diameter of the present is bigger than that of Koizumi et al.'s experiments. In comparison of present experiments with the Richter et al.'s experiments, diameter is similar, but the gap thickness of the present is smaller than that of Richter et al.'s experiments. It is judged from these results that correlation development on CCFL to consider gap thickness is reasonable at similar condition of diameter.The developed correlation will be used to develop the CHFG model. 36 refs., 26 figs., 7 tabs. (Author)

  18. Comparison of Simulation and Experimental Results of Class - D Inverter Fed Induction Heater

    Directory of Open Access Journals (Sweden)

    S. Rama Reddy

    2010-10-01

    Full Text Available This research deals w ith simulation and experimentation of closed loop controlled class-D inverter fed induction heater system. This converter has reduced switching losses, stress and increased power density. The inverter system is designed and the simulation is done using Matlab. The results of simulation and experimentation are presented. The induction heater system uses embedded controller to generate driving pulses. The objective is to develop an induction heater system with minimum hardware.

  19. Experimental results from the CEA Reactor Physics Programme on MARIUS III

    Energy Technology Data Exchange (ETDEWEB)

    Bosser, R.; Langlet, G.; Morier, F.

    1971-01-15

    A programme of experimental studies on the physics of HTR lattices was proposed in 1968. Under the authority of the EDF-CEA joint comittee, decision to achieve this programmes was taken in Jyly 1969. Less than one year after, MARIUS III had its first divergence in its new configuration and the experiments began in August 1970. After preliminary experiments, phase one of the programme was achieved in October, November and December 1970. Experimental results are presented.

  20. Updating Finite Element Model of a Wind Turbine Blade Section Using Experimental Modal Analysis Results

    DEFF Research Database (Denmark)

    Luczak, Marcin; Manzato, Simone; Peeters, Bart;

    2014-01-01

    of model parameters was selected for the model updating process. Design of experiment and response surface method was implemented to find values of model parameters yielding results closest to the experimental. The updated finite element model is producing results more consistent with the measurement...... is to validate finite element model of the modified wind turbine blade section mounted in the flexible support structure accordingly to the experimental results. Bend-twist coupling was implemented by adding angled unidirectional layers on the suction and pressure side of the blade. Dynamic test and simulations...... were performed on a section of a full scale wind turbine blade provided by Vestas Wind Systems A/S. The numerical results are compared to the experimental measurements and the discrepancies are assessed by natural frequency difference and modal assurance criterion. Based on sensitivity analysis, set...

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

    Science.gov (United States)

    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.

  2. Thermodiffusion in concentrated ferrofluids: Experimental and numerical results on magnetic thermodiffusion

    Energy Technology Data Exchange (ETDEWEB)

    Sprenger, Lisa, E-mail: Lisa.Sprenger@tu-dresden.de; Lange, Adrian; Odenbach, Stefan [Institute of Fluid Mechanics, Chair of Magnetofluiddynamics, Measuring and Automation Technology, TU Dresden, 01062 Dresden (Germany)

    2014-02-15

    Ferrofluids consist of magnetic nanoparticles dispersed in a carrier liquid. Their strong thermodiffusive behaviour, characterised by the Soret coefficient, coupled with the dependency of the fluid's parameters on magnetic fields is dealt with in this work. It is known from former experimental investigations on the one hand that the Soret coefficient itself is magnetic field dependent and on the other hand that the accuracy of the coefficient's experimental determination highly depends on the volume concentration of the fluid. The thermally driven separation of particles and carrier liquid is carried out with a concentrated ferrofluid (φ = 0.087) in a horizontal thermodiffusion cell and is compared to equally detected former measurement data. The temperature gradient (1 K/mm) is applied perpendicular to the separation layer. The magnetic field is either applied parallel or perpendicular to the temperature difference. For three different magnetic field strengths (40 kA/m, 100 kA/m, 320 kA/m) the diffusive separation is detected. It reveals a sign change of the Soret coefficient with rising field strength for both field directions which stands for a change in the direction of motion of the particles. This behaviour contradicts former experimental results with a dilute magnetic fluid, in which a change in the coefficient's sign could only be detected for the parallel setup. An anisotropic behaviour in the current data is measured referring to the intensity of the separation being more intense in the perpendicular position of the magnetic field: S{sub T‖} = −0.152 K{sup −1} and S{sub T⊥} = −0.257 K{sup −1} at H = 320 kA/m. The ferrofluiddynamics-theory (FFD-theory) describes the thermodiffusive processes thermodynamically and a numerical simulation of the fluid's separation depending on the two transport parameters ξ{sub ‖} and ξ{sub ⊥} used within the FFD-theory can be implemented. In the case of a parallel aligned magnetic field

  3. Single-Case Experimental Designs: A Systematic Review of Published Research and Current Standards

    Science.gov (United States)

    Smith, Justin D.

    2013-01-01

    This article systematically reviews the research design and methodological characteristics of single-case experimental design (SCED) research published in peer-reviewed journals between 2000 and 2010. SCEDs provide researchers with a flexible and viable alternative to group designs with large sample sizes. However, methodological challenges have precluded widespread implementation and acceptance of the SCED as a viable complementary methodology to the predominant group design. This article includes a description of the research design, measurement, and analysis domains distinctive to the SCED; a discussion of the results within the framework of contemporary standards and guidelines in the field; and a presentation of updated benchmarks for key characteristics (e.g., baseline sampling, method of analysis), and overall, it provides researchers and reviewers with a resource for conducting and evaluating SCED research. The results of the systematic review of 409 studies suggest that recently published SCED research is largely in accordance with contemporary criteria for experimental quality. Analytic method emerged as an area of discord. Comparison of the findings of this review with historical estimates of the use of statistical analysis indicates an upward trend, but visual analysis remains the most common analytic method and also garners the most support amongst those entities providing SCED standards. Although consensus exists along key dimensions of single-case research design and researchers appear to be practicing within these parameters, there remains a need for further evaluation of assessment and sampling techniques and data analytic methods. PMID:22845874

  4. Glazed clay pottery and lead exposure in Mexico: Current experimental evidence.

    Science.gov (United States)

    Diaz-Ruiz, Araceli; Tristán-López, Luis Antonio; Medrano-Gómez, Karen Itzel; Torres-Domínguez, Juan Alejandro; Ríos, Camilo; Montes, Sergio

    2017-11-01

    Lead exposure remains a significant environmental problem; lead is neurotoxic, especially in developing humans. In Mexico, lead in human blood is still a concern. Historically, much of the lead exposure is attributed to the use of handcrafted clay pottery for cooking, storing and serving food. However, experimental cause-and-effect demonstration is lacking. The present study explores this issue with a prospective experimental approach. We used handcrafted clay containers to prepare and store lemonade, which was supplied as drinking water to pregnant rats throughout the gestational period. We found that clay pots, jars, and mugs leached on average 200 µg/l lead, and exposure to the lemonade resulted in 2.5 µg/dl of lead in the pregnant rats' blood. Neonates also showed increased lead content in the hippocampus and cerebellum. Caspase-3 activity was found to be statistically increased in the hippocampus in prenatally exposed neonates, suggesting increased apoptosis in that brain region. Glazed ceramics are still an important source of lead exposure in Mexico, and our results confirm that pregnancy is a vulnerable period for brain development.

  5. A comparison between numerical predictions and theoretical and experimental results for laminar core-annular flow

    NARCIS (Netherlands)

    Beerens, J.C.; Ooms, G.; Pourquie, M.J.B.M.; Westerweel, J.

    2014-01-01

    high-viscosity liquid core surrounded by a laminar low-viscosity liquid annular layer through a vertical pipe. The numerical results are compared with theoretical results from linear stability calculations and with experimental data. The comparison is good and the general conclusion of our study is

  6. Experimental study on hydrodynamic characteristics of vertical-axis floating tidal current energy power generation device

    Science.gov (United States)

    Ma, Yong; Li, Teng-fei; Zhang, Liang; Sheng, Qi-hu; Zhang, Xue-wei; Jiang, Jin

    2016-10-01

    To study the characteristics of attenuation, hydrostatic towage and wave response of the vertical-axis floating tidal current energy power generation device (VAFTCEPGD), a prototype is designed and experiment is carried out in the towing tank. Free decay is conducted to obtain attenuation characteristics of the VAFTCEPGD, and characteristics of mooring forces and motion response, floating condition, especially the lateral displacement of the VAFTCEPGD are obtained from the towing in still water. Tension response of the #1 mooring line and vibration characteristics of the VAFTCEPGD in regular waves as well as in level 4 irregular wave sea state with the current velocity of 0.6 m/s. The results can be reference for theoretical study and engineering applications related to VAFTCEPGD.

  7. Participation in a trauma-focused epidemiological investigation may result in sensitization for current health problems

    NARCIS (Netherlands)

    Verschuur, M.J.; Spinhoven, Ph.; van Emmerik, A.A.P.; Rosendaal, F.R.

    2008-01-01

    Objectives - Participation in health survey research may result in a worsening of self-assessed health status and enhanced service-use by increasing self-awareness of current health status. The present study investigated whether participation in a traumafocused epidemiological study sensitized parti

  8. Harmonic Analysis of Currents and Voltages Obtained in the Result of Computational Experiment

    Directory of Open Access Journals (Sweden)

    I. V. Novash

    2011-01-01

    Full Text Available The paper considers a methodology for execution of a harmonic analysis of current and voltage numerical values obtained in the result of a computational experiment and saved in an external data file. The harmonic analysis has been carried out in the Mathcad mathematical packet environment.

  9. Current Parental Depression and Offspring Perceived Self-Competence: A Quasi-Experimental Examination

    Science.gov (United States)

    Class, Quetzal A.; D’Onofrio, Brian M.; Singh, Amber L.; Ganiban, Jody M.; Spotts, E. L.; Lichtenstein, Paul; Reiss, David; Neiderhiser, Jenae M.

    2013-01-01

    A genetically-informed, quasi-experimental design was used to examine the genetic and environmental processes underlying associations between current parental depressive symptoms and offspring perceived self-competence. Participants, drawn from a population-based Swedish sample, were 852 twin pairs and their male (52%) and female offspring aged 15.7 ± 2.4 years. Parental depressive symptoms were measured using the Center for Epidemiological Studies Depression scale. Offspring perceived self-competence was measured using a modified Harter Perceived Competence Scale. Cousin comparisons and Children of Twins (CoT) designs suggested that associations between maternal depressive symptoms and offspring perceived self-competence were due to shared genetic/environmental liability. The mechanism responsible for father-offspring associations, however, was independent of genetic factors and of extended-family environmental factors, supporting a causal inference. Thus, mothers and fathers may impact offspring perceived self-competence via different mechanisms and unmeasured genetic and environmental selection factors must be considered when studying the intergenerational transmission of cognitive vulnerabilities for depression. PMID:22692226

  10. Hazards by shock waves during explosive eruptions: preliminary results of experimental investigations.

    Science.gov (United States)

    Scolamacchia, Teresa; Alatorre Ibarguengoïtia, Miguel; Spieler, Oliver; Dingwell, Donald B.

    2010-05-01

    velocities (205 to 257 m/s) were obtained for smaller grain-sizes, in a range of fine lapilli-medium ash (2.8 to 177 μm). Lower velocities, 40 m/s to 85 m/s, were attained by medium (8 mm) and fine lapilli (4 mm), respectively. These values seem not directly related to the the material composition. Impacts craters on steel plates were experimentally obtained, but we did not observe a modification of the steel inner structure, as observed in the original impacted pole. These results are in agreement with impacts occurred at low particle velocities, typical for gravity driven currents, as those reached in these experiments. We observed a great reduction in grain-size of samples recovered after all experiments with respect to the original material. Such evidence coud be due not only to the disruption of grains when impacting the metal plate, but also to processes stricly related to shock wave propagation and gas expansion. These preliminary results need to be further investigated.

  11. Experimental and numerical results of a high frequency rotating active magnetic refrigerator

    DEFF Research Database (Denmark)

    Lozano, Jaime; Engelbrecht, Kurt; Bahl, Christian

    2012-01-01

    Experimental results for a recently developed prototype magnetic refrigeration device at The Technical University of Denmark (DTU) were obtained and compared with numerical simulation results. A continuously rotating active magnetic regenerator (AMR) using 2.8 kg packed sphere regenerators...... experimentally and implemented in a one-dimensional numerical AMR model that includes also the parasitic losses from the prototype. The temperature span for a thermal load of 200 W as a function of frequency was measured and modelled. Moreover, the temperature span dependence on the cooling capacity...

  12. Armature reaction effects on a high temperature superconducting field winding of an synchronous machine: experimental results

    DEFF Research Database (Denmark)

    Mijatovic, Nenad; Jensen, Bogi Bech

    2014-01-01

    This paper presents experimental results from the Superwind laboratory setup. Particular focus in the paper has been placed on describing and quantifying the influence of armature reaction on performance of the HTS filed winding. Presented experimental results have confirmed the HTS field winding...... sensitivity to both armature reaction intensity and angular position with respect to the HTS coils. Furthermore, the characterization of the HTS field winding has been correlated to the electromagnetic torque of the machine where the maximal Ic reduction of 21% has been observed for the maximum torque....

  13. Armature reaction effects on a high temperature superconducting field winding of an synchronous machine: experimental results

    Science.gov (United States)

    Mijatovic, Nenad; Jensen, Bogi Bech

    2014-05-01

    This paper presents experimental results from the Superwind laboratory setup. Particular focus in the paper has been placed on describing and quantifying the influence of armature reaction on performance of the HTS filed winding. Presented experimental results have confirmed the HTS field winding sensitivity to both armature reaction intensity and angular position with respect to the HTS coils. Furthermore, the characterization of the HTS field winding has been correlated to the electromagnetic torque of the machine where the maximal Ic reduction of 21% has been observed for the maximum torque.

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

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, Louise F. [NorthernSTAR, St. Paul, MN (United States); Harmon, Anna C. [NorthernSTAR, St. Paul, MN (United States)

    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.

  15. High fidelity studies of exploding foil initiator bridges, Part 2: Experimental results

    Science.gov (United States)

    Neal, William; Bowden, Mike

    2017-01-01

    Simulations of high voltage detonators, such as Exploding Bridgewire (EBW) and Exploding Foil Initiators (EFI), have historically been simple, often empirical, one-dimensional models capable of predicting parameters such as current, voltage, and in the case of EFIs, flyer velocity. Experimental methods have correspondingly generally been limited to the same parameters. With the advent of complex, first principles magnetohydrodynamic codes such as ALEGRA MHD, it is now possible to simulate these components in three dimensions and predict greater range of parameters than before. A significant improvement in experimental capability was therefore required to ensure these simulations could be adequately verified. In this second paper of a three part study, data is presented from a flexible foil EFI header experiment. This study has shown that there is significant bridge expansion before time of peak voltage and that heating within the bridge material is spatially affected by the microstructure of the metal foil.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  17. Synthetic analyses of the LAVA experimental results on in-vessel corium retention through gap cooling

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Kyoung Ho; Cho, Young Ro; Koo, Kil Mo; Park, Rae Joon; Kim, Jong Hwan; Kim, Jong Tae; Ha, Kwang Sun; Kim, Sang Baik; Kim, Hee Dong

    2001-03-01

    LAVA(Lower-plenum Arrested Vessel Attack) has been performed to gather proof of gap formation between the debris and lower head vessel and to evaluate the effect of the gap formation on in-vessel cooling. Through the total of 12 tests, the analyses on the melt relocation process, gap formation and the thermal and mechanical behaviors of the vessel were performed. The thermal behaviors of the lower head vessel were affected by the formation of the fragmented particles and melt pool during the melt relocation process depending on mass and composition of melt and subcooling and depth of water. During the melt relocation process 10.0 to 20.0 % of the melt mass was fragmented and also 15.5 to 47.5 % of the thermal energy of the melt was transferred to water. The experimental results address the non-adherence of the debris to the lower head vessel and the consequent gap formation between the debris and the lower head vessel in case there was an internal pressure load across the vessel abreast with the thermal load induced by the thermite melt. The thermal behaviors of the lower head vessel during the cooldown period were mainly affected by the heat removal characteristics through this gap, which were determined by the possibilities of the water ingression into the gap depending on the melt composition of the corium simulant. The enhanced cooling capacity through the gap was distinguished in the Al{sub 2}O{sub 3} melt tests. It could be inferred from the analyses on the heat removal capacity through the gap that the lower head vessel could effectively cooldown via heat removal in the gap governed by counter current flow limits(CCFL) even if 2mm thick gap should form in the 30 kg Al{sub 2}O{sub 3} melt tests, which was also confirmed through the variations of the conduction heat flux in the vessel and rapid cool down of the vessel outer surface in the Al{sub 2}O{sub 3} melt tests. In the case of large melt mass of 70 kg Al{sub 2}O{sub 3} melt, however, the infinite

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

    Science.gov (United States)

    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. Studies of challenge in lower hybrid current drive capability at high density regime in experimental advanced superconducting tokamak

    Science.gov (United States)

    Ding, B. J.; Li, M. H.; Li, Y. C.; Wang, M.; Liu, F. K.; Shan, J. F.; Li, J. G.; Wan, B. N.; Wan

    2017-02-01

    Aiming at a fusion reactor, two issues must be solved for the lower hybrid current drive (LHCD), namely good lower hybrid wave (LHW)-plasma coupling and effective current drive at high density. For this goal, efforts have been made to improve LHW-plasma coupling and current drive capability at high density in experimental advanced superconducting tokamak (EAST). LHW-plasma coupling is improved by means of local gas puffing and gas puffing from the electron side is taken as a routine way for EAST to operate with LHCD. Studies of high density experiments suggest that low recycling and high lower hybrid (LH) frequency are preferred for LHCD experiments at high density, consistent with previous results in other machines. With the combination of 2.45 GHz and 4.6 GHz LH waves, a repeatable high confinement mode plasma with maximum density up to 19~\\text{m}-3$ was obtained by LHCD in EAST. In addition, in the first stage of LHCD cyclic operation, an alternative candidate for more economical fusion reactors has been demonstrated in EAST and further work will be continued.

  20. Updating Finite Element Model of a Wind Turbine Blade Section Using Experimental Modal Analysis Results

    Directory of Open Access Journals (Sweden)

    Marcin Luczak

    2014-01-01

    Full Text Available This paper presents selected results and aspects of the multidisciplinary and interdisciplinary research oriented for the experimental and numerical study of the structural dynamics of a bend-twist coupled full scale section of a wind turbine blade structure. The main goal of the conducted research is to validate finite element model of the modified wind turbine blade section mounted in the flexible support structure accordingly to the experimental results. Bend-twist coupling was implemented by adding angled unidirectional layers on the suction and pressure side of the blade. Dynamic test and simulations were performed on a section of a full scale wind turbine blade provided by Vestas Wind Systems A/S. The numerical results are compared to the experimental measurements and the discrepancies are assessed by natural frequency difference and modal assurance criterion. Based on sensitivity analysis, set of model parameters was selected for the model updating process. Design of experiment and response surface method was implemented to find values of model parameters yielding results closest to the experimental. The updated finite element model is producing results more consistent with the measurement outcomes.

  1. Resonant pickups for non-destructive single-particle detection in heavy-ion storage rings and first experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Sanjari, Mohammad Shahab

    2013-04-26

    Nuclear astrophysics studies on highly charged radionuclides benefit from accelerator facilities with storage rings, where exotic nuclides produced with small yields can be efficiently investigated. Currently there are two accelerator facilities capable of storing highly charged heavy ions, GSI in Darmstadt and IMP in Lanzhou. Non-destructive detection methods are often used for in-flight measurements based on frequency analysis. The sensitivity of such detection systems are of primary importance specially when number of stored ions is small. Furthermore, since the exotic nuclides of interest are as a rule short-lived, the detectors must be fast. One common form of such detectors are parallel plate SCHOTTKY monitors, on which particles induce a mirror charge at each passage. This method has been successfully used at ESR experimental storage ring of GSI since 1991. In this work we describe a new resonant SCHOTTKY pickup operating as a high sensitive cavity current monitor which was mounted and commissioned in the ESR early 2010. It was successfully used in several storage ring experiments. A very similar pickup was mounted in CSRe at IMP Lanzhou in 2011. First in-ring tests have been performed and new experimental results are pending. The spectral analysis of acquired signals by the new detector has enabled a broad range of new physics experiments. The theory of operation and first experimental results and future perspectives are presented in this thesis.

  2. Experimental Measurement of Asymmetric Fluctuations of Poloidal Magnetic Field in Damavand Tokomak at Different Plasma Currents

    Science.gov (United States)

    Moslehi-Fard, Mahmoud; Alinejad, Naser; Rasouli, Chapar; Sadigzadeh, Asghar

    2012-08-01

    Toroidal and Poloidal magnetic fields have an important effect on the tokomak topology. Damavand Tokomak is a small size tokomak characterized with k = 1.2, B t = 1T, R 0 = 36 cm, maximum plasma current is about 35 KA with a discharge time of 21 ms. In this experimental work, the variation of poloidal magnetic field on the torodial cross section is measured and analyzed. In order to measure the polodial magnetic field, 18 probes were installed on the edge of tokomak plasma with ∆θ = 18°, while a limiter was installed inside the torus. Plasma current, I p, induces a polodial magnetic field, B p, smaller than the torodial magnetic field B t. Magnetic lines B produced as a combination of B t and B p, are localized on the nested toroidal magnetic surfaces. The presence of polodial magnetic field is necessary for particles confinement. Mirnov oscillations are the fluctuations of polodial magnetic field, detected by magnetic probes. Disrupted instability in Tokomak typically starts with mirnov oscillations which appear as fluctuations of polodial magnetic field and is detected by magnetic probes. Minor disruptions inside the plasma can contain principal magnetic islands and their satellites can cause the annihilation of plasma confinement. Production of thin layer of turbulent magnetic field lines cause minor disruption. Magnetic limiter may cause the deformation of symmetric equilibrium configuration and chaotic magnetic islands reveal in plasma occurring in thin region of chaotic field lines close to their separatrix. The width of this chaotic layer in the right side of poloidal profile of Damavand Tokomak is smaller than the width in the left side profile because of Shafranov displacement. Ergodic region in the left side of profile develops a perturbation on the magnetic polodial field lines, B p, that are greater in magnitude than that in the right side, although the values of B p on the left side are smaller than that on the right side of the profile. The Left

  3. Experimental study of a high-current FEM with a broadband microwave system

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, G.G.; Bratman, V.L.; Ginzburg, N.S. [Institute of Applied Physics, Nizhny Novgorod (Russian Federation)] [and others

    1995-12-31

    One of the main features of FELs and FEMs is the possibility of fast and wideband tuning of the resonant frequency of active media, which can be provided by changing the particle energy. For a frequency adjustable FEM-oscillator, a broadband microwave system, which is simply combined with an electron-optical FEM system and consists of an oversized waveguide and reflectors based on the microwave beams multiplication effect has been proposed and studied successfully in {open_quotes}cold{close_quotes} measurements. Here, the operating ability of a cavity, that includes some key elements of the broadband microwave system, was tested in the presence of an electron beam. To provide large particle oscillation velocities in a moderate undulator field and the presence of a guide magnetic field, the FEM operating regime of double resonance was chosen. In this regime the cyclotron as well as undulator resonance conditions were satisfied. The FEM-oscillator was investigated experimentally on a high-current accelerator {open_quotes}Sinus-6{close_quotes} that forms an electron beam with particle energy 500keV and pulse duration 25ns. The aperture with a diameter 2.5mm at the center of the anode allows to pass through only the central fraction of the electron beam with a current about 100A and a small spread of longitudinal velocities of the particles. Operating transverse velocity was pumped into the electron beam in the pulse plane undulator of a 2.4cm period. The cavity with a frequency near 45GHz consists of a square waveguide and two reflectors. The broadband up-stream reflector based on the multiplication effect had the power reflectivity coefficient more than 90% in the frequency band 10% for the H{sup 10} wave of the square waveguide with the maximum about 100% at a frequency 45GHz. The down-stream narrow-band Bragg reflector had the power reflection coefficient approximately 80% in the frequency band of 4% near 45GHz for the operating mode.

  4. A Failure Mode in Dense Infrared Detector Arrays Resulting in Increased Dark Current

    Science.gov (United States)

    Pinkie, Benjamin; Bellotti, Enrico

    2016-09-01

    In this paper, we investigate a failure mode that arises in dense infrared focal plane detector arrays as a consequence of the interactions of neighboring pixels through the minority carrier profiles in the common absorber layer. We consider the situation in which one pixel in a hexagonal array becomes de-biased relative to its neighbors and show that the dark current in the six neighboring pixels increases exponentially as a function of the difference between the nominal and anomalous biases. Moreover, we show that the current increase in the six nearest-neighbor pixels is in total larger than that by which the current in the affected pixel decreases, causing a net increase in the dark current. The physical origins of this effect are explained as being due to increased lateral diffusion currents that arise as a consequence of breaking the symmetry of the minority carrier profiles. We then perform a parametric study to quantify the magnitude of this effect for a number of detector geometric parameters, operating temperatures, and spectral bands. Particularly, numerical simulations are carried out for short-, mid-, and long-wavelength HgCdTe infrared detectors operating between 77 K and 210 K. We show that this effect is most prevalent in architectures for which the lateral diffusion current is the largest component of the total dark current—high operating temperature devices with narrow epitaxial absorber thicknesses and pitches small compared to the diffusion length of minority carriers. These results could prove significant particularly for short- and mid-wave infrared detectors, which are typically designed to fit these conditions.

  5. Simulation and experimental results of kaleidoscope homogenizers for longitudinal diode pumping.

    Science.gov (United States)

    Bartnicki, Eric; Bourdet, Gilbert L

    2010-03-20

    With the goal to set a homogenizer to allow coupling of a stack of diodes with a disk amplifier medium for a longitudinally pumped laser or amplifier, we report simulation and experimental results on homogenization of the light supplied by a large stack of diodes. We investigate various kaleidoscope cross-section shapes and various optical coupling configurations.

  6. Results of experimental research of the modes of short circuit in a traction network

    Directory of Open Access Journals (Sweden)

    P.Ye. Mykhalichenko

    2012-08-01

    Full Text Available In the article the results, namely oscillograms of the transitional feeder electric values obtained by the experimental tests of the short circuit modes in case of setting off different types of substation fast-acting switches are presented. The experiments were conducted on the operating electrified track sections of the Prydniprovs’ka Railway.

  7. Neuro-fuzzy control synthesis for hydrostatic type servoactuators. Experimental results

    Directory of Open Access Journals (Sweden)

    Felicia URSU

    2009-12-01

    Full Text Available Continuing recent works of the authors, the paper shows the developing and the application of aneuro-fuzzy control law to the positioning outer loop of a hydrostatic type servoactuator.Experimental results are presented concerning dynamical behavior of the system by using this“intelligent” controller. Finally, arguments about the advantages of the new designed controller aresummarized.

  8. Results of an Experimental Study of the Langlee Wave Energy Converter

    DEFF Research Database (Denmark)

    Pecher, Arthur; Kofoed, Jens Peter; Espedal, J.

    2010-01-01

    This paper presents the results of the first experimental study of the Langlee wave energy converter (WEC), a semi-submerged oscillating wave surge converter. Its design extracts the energy from the surge motion of the waves through two pairs of working flaps, called water wings, which are placed...

  9. Experimental results for the Poincar\\'e center problem (including an Appendix with Martin Cremer)

    OpenAIRE

    Bothmer, Hans-Christian Graf v.

    2005-01-01

    Comment: 16 pages, 2 figures, source code of programs at http://www-ifm.math.uni-hannover.de/~bothmer/strudel/. Added references, the result of Example 6.2 is not new. Added two new sections on rationally reversible systems. The 4th codim 7 component we saw only experimentally can now also be identified geometricaly

  10. Photon Detection with Cooled Avalanche Photodiodes: Theory and Preliminary Experimental Results

    Science.gov (United States)

    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.

  11. Experimental validation of the twins prediction program for rolling noise. Pt.2: results

    NARCIS (Netherlands)

    Thompson, D.J.; Fodiman, P.; Mahé, H.

    1996-01-01

    Two extensive measurement campaigns have been carried out to validate the TWINS prediction program for rolling noise, as described in part 1 of this paper. This second part presents the experimental results of vibration and noise during train pass-bys and compares them with predictions from the TWIN

  12. Fuzzy logic analysis optimizations for pattern recognition - Implementation and experimental results

    Science.gov (United States)

    Hires, Matej; Habiballa, Hashim

    2017-07-01

    The article presents an practical results of optimization of the fuzzy logic analysis method for pattern recognition. The theoretical background of the proposed theory is shown in the former article extending the original fuzzy logic analysis method. This article shows the implementation and experimental verification of the approach.

  13. At Odds: Reconciling Experimental and Theoretical Results in High School Physics

    Science.gov (United States)

    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.)

  14. Experimental validation of the twins prediction program for rolling noise. Pt.2: results

    NARCIS (Netherlands)

    Thompson, D.J.; Fodiman, P.; Mahé, H.

    1996-01-01

    Two extensive measurement campaigns have been carried out to validate the TWINS prediction program for rolling noise, as described in part 1 of this paper. This second part presents the experimental results of vibration and noise during train pass-bys and compares them with predictions from the

  15. [Regeneration of endocrine gastroenteropancreatic system in experimental and clinical pathology: concept development and current problems].

    Science.gov (United States)

    Ivanova, V F

    2013-01-01

    Literature review contains the literature data and the results of author's own investigations describing the coming into being and the development of the concepts on the regeneration of endocrine gastroenteropancreatic (GEP) system under the conditions of norm, experimental and clinical pathology. Data analysis permitted to reveal the similarities and differences in the course of this process in various organs of the digestive system. Endocrine GEP system renewal occurs at different levels of its organization. At the tissue level, the endocrine cells renewal occurs via the transformation of exocrine cells into the endocrine ones and as a result of differentiation from stem cells via the "agranular" cell stage which are precursors of the endocrine cells. This pathway of regeneration is the major one after the damage. Regeneration at cellular level occurs through mitotic division of the differentiated endocrine cells (early stage of regeneration) and as a result of the formation granules with different hormonal profile in D-cells. At the intracellular level, the regeneration is realized through the intracellular structure restoration after their damage induced by the increase of cell functional activity accompanied by degranulation and dystrophic changes development

  16. Current and experimental treatments of Parkinson disease: A guide for neuroscientists.

    Science.gov (United States)

    Oertel, Wolfgang; Schulz, Jörg B

    2016-10-01

    Over a period of more than 50 years, the symptomatic treatment of the motor symptoms of Parkinson disease (PD) has been optimized using pharmacotherapy, deep brain stimulation, and physiotherapy. The arsenal of pharmacotherapies includes L-Dopa, several dopamine agonists, inhibitors of monoamine oxidase (MAO)-B and catechol-o-methyltransferase (COMT), and amantadine. In the later course of the disease, motor complications occur, at which stage different oral formulations of L-Dopa or dopamine agonists with long half-life, a transdermal application or parenteral pumps for continuous drug supply can be subscribed. Alternatively, the patient is offered deep brain stimulation of the subthalamic nucleus (STN) or the internal part of the globus pallidus (GPi). For a more efficacious treatment of motor complications, new formulations of L-Dopa, dopamine agonists, and amantadine as well as new MAO-B and COMT inhibitors are currently tested in clinical trials, and some of them already yielding positive results in phase 3 trials. In addition, non-dopaminergic agents have been tested in the early clinical phase for the treatment of motor fluctuations and dyskinesia, including adenosine A2A antagonists (istradefylline, preladenant, and tozadenant) and modulators of the metabolic glutamate receptor 5 (mGluR5 - mavoglurant) and serotonin (eltoprazine) receptors. Recent clinical trials testing coenzyme Q10, the dopamine agonist pramipexole, creatine monohydrate, pioglitazone, or AAV-mediated gene therapy aimed at increasing expression of neurturin, did not prove efficacious. Treatment with nicotine, caffeine, inosine (a precursor of urate), and isradipine (a dihydropyridine calcium channel blocker), as well as active and passive immunization against α-synuclein and inhibitors or modulators of α-synuclein-aggregation are currently studied in clinical trials. However, to date, no disease-modifying treatment is available. We here review the current status of treatment options for

  17. Vertical Instability in EAST: Comparison of Model Predictions with Experimental Results

    Institute of Scientific and Technical Information of China (English)

    QIAN Jinping; WAN Baonian; SHEN Biao; XIAO Bingjia; SUN Youwen; SHI Yuejiang; LIN Shiyao; LI Jiangang; GONG Xianzu

    2008-01-01

    Growth rates of the axisymmetric mode in elongated plasmas in the experimental advanced superconducting tokamak (EAST) are measured with zero feedback gains and then compared with numerically calculated growth rates for the reconstructed shapes. The comparison is made after loss of vertical position control. The open-loop growth rates were scanned with the number of vessel eigenmodes, which up to 20 is enough to make the growth rates settled. The agreement between the growth rates measured experimentally and the growth rates determined numerically is good. The results show that a linear RZIP model is essentially good enough for the vertical position feedback control.

  18. Experimental Results of the Superluminescent Fiber Laser Sources for Fiber Optic Sensors

    Directory of Open Access Journals (Sweden)

    E. F. Pinzón-Escobar

    2012-03-01

    Full Text Available We are presenting experimental work on an erbium-doped fiber operating in the superluminescent regime. Experimental results for different pump power levels and fiber length show that the theoretical and numerical model could render useful information for predicting the total output power as a function of fiber doped length and the input pump power. These types of sources could have direct application in wavelength multiplexed arrangements of fiber sensors, fiber gyroscopes or, in general, in any sensors in which a broad wavelength and stable light source is required.

  19. 'I think it will eventually be done away with': Attitudes among healthcare professionals towards the current system of animal experimentation.

    Science.gov (United States)

    Dignon, Andrée

    2016-08-01

    This article describes a study of attitudes to the current system of animal experimentation (for the production of health interventions) among 52 UK healthcare professionals. These healthcare professionals participated in three separate focus groups (of 18, 17 and 17 participants) and were invited to respond to the question 'what is your opinion about the current system of animal testing?' The study focused specifically on their views of the current system (rather than their views of animal testing in general). The healthcare professionals were critical of the current system, particularly with regard to regulation, secrecy, validity, unnecessary suffering and welfare. © The Author(s) 2014.

  20. Isothermal (vapour + liquid) equilibrium of (cyclic ethers + chlorohexane) mixtures: Experimental results and SAFT modelling

    Energy Technology Data Exchange (ETDEWEB)

    Bandres, I.; Giner, B.; Lopez, M.C.; Artigas, H. [Departamento de Quimica Organica y Quimica Fisica, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); Lafuente, C. [Departamento de Quimica Organica y Quimica Fisica, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain)], E-mail: celadi@unizar.es

    2008-08-15

    Experimental data for the isothermal (vapour + liquid) equilibrium of mixtures formed by several cyclic ethers (tetrahydrofuran, tetrahydropyran, 1,3-dioxolane, and 1,4-dioxane) and chlorohexane at temperatures of (298.15 and 328.15) K are presented. Experimental results have been discussed in terms of both, molecular characteristics of pure compounds and potential intermolecular interaction between them using thermodynamic information of the mixtures obtained earlier. Furthermore, the influence of the temperature on the (vapour + liquid) equilibrium of these mixtures has been explored and discussed. Transferable parameters of the SAFT-VR approach together with standard combining rules have been used to model the phase equilibrium of the mixtures and a description of the (vapour + liquid) equilibrium of them that is in excellent agreement with the experimental data are provided.

  1. Comparison of ONIX simulation results with experimental data from the BATMAN testbed for the study of negative ion extraction

    Science.gov (United States)

    Mochalskyy, Serhiy; Fantz, Ursel; Wünderlich, Dirk; Minea, Tiberiu

    2016-10-01

    The development of negative ion (NI) sources for the ITER neutral beam injector is strongly accompanied by modelling activities. The ONIX (Orsay Negative Ion eXtraction) code simulates the formation and extraction of negative hydrogen ions and co-extracted electrons produced in caesiated sources. In this paper the 3D geometry of the BATMAN extraction system, and the source characteristics such as the extraction and bias potential, and the 3D magnetic field were integrated in the model. Calculations were performed using plasma parameters experimentally obtained on BATMAN. The comparison of the ONIX calculated extracted NI density with the experimental results suggests that predictive calculations of the extraction of NIs are possible. The results show that for an ideal status of the Cs conditioning the extracted hydrogen NI current density could reach ~30 mA cm-2 at 10 kV and ~20 mA cm-2 at 5 kV extraction potential, with an electron/NI current density ratio of about 1, as measured in the experiments under the same plasma and source conditions. The dependency of the extracted NI current on the NI density in the bulk plasma region from both the modeling and the experiment was investigated. The separate distributions composing the NI beam originating from the plasma bulk region and the PG surface are presented for different NI plasma volume densities and NI emission rates from the plasma grid (PG) wall, respectively. The extracted current from the NIs produced at the Cs covered PG surface, initially moving towards the bulk plasma and then being bent towards the extraction surfaces, is lower compared to the extracted NI current from directly extracted surface produced ions.

  2. Numerical analysis of temperature field during hardfacing process and comparison with experimental results

    Directory of Open Access Journals (Sweden)

    Lazić Vukić N.

    2014-01-01

    Full Text Available The three-dimensional transient nonlinear thermal analysis of the hard facing process is performed by using the finite element method. The simulations were executed on the open source Salome platform using the open source finite element solver Code_Aster. The Gaussian double ellipsoid was selected in order to enable greater possibilities for the calculation of the moving heat source. The numerical results were compared with available experimental results.

  3. In-medium properties of hadrons – Recent experimental results and perspectives

    Indian Academy of Sciences (India)

    Volker Metag

    2006-05-01

    Recent experimental results on the modification of hadron properties in a nuclear medium are discussed. Experiments using hadron, heavy-ion and photon beams are described. Particular emphasis is given to the photonuclear production of light vector mesons and scalar mesons off nuclei. Recent results on the search for meson-nucleus bound states are presented. Perspectives for extending these studies to the charm sector are outlined.

  4. New hadronic currents in TAUOLA: for confrontation with the experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Was, Z. [Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Cracow (Poland); CERN, 1211 Geneva (Switzerland)

    2012-04-15

    The status of implementation of new hadronic currents into the Monte Carlo system for simulation of {tau}-lepton production and decay in high-energy accelerator experiments is reviewed. Since the {tau}-lepton conference in 2010 substantial progress was achieved: (i) For the TAUOLA Monte Carlo generator of {tau}-lepton decays, automated and simultaneous use of many versions of form factors for the calculation of optional weights for fits was developed and checked to work in the Belle and BaBar software environment. Alternative parameterizations of hadronic currents based on the Resonance Chiral approach are available now. This was achieved for more than 88% of the total {tau} hadronic width. (ii) the TAUOLA universal interface based on HepMC (the C++ event record) is available. This is the case for C++ users of PHOTOS Monte Carlo for radiative corrections in decays, as well. An algorithm for weighted events to explore spin effects in analysis of hard processes was prepared. (iii) Kernels featuring a complete first-order matrix element are available now for PHOTOS users interested in decays of Z and W bosons. New tests with different options of matrix elements for those and for K{sub l3} decays are available as well. Presented results illustrate the status of the projects performed in collaboration with Zofia Czyczula, Nadia Davidson, Tomasz Przedzinski, Olga Shekhovtsova, Elzbieta Richter-Was, Pablo Roig, Qingjun Xu and others.

  5. An Experimental Study on the Darrieus-Savonius Turbine for the Tidal Current Power Generation

    Science.gov (United States)

    Kyozuka, Yusaku

    The Darrieus turbine is popular for tidal current power generation in Japan. It is simple in structure with straight wings rotating around a vertical axis, so that it has no directionality against the motion of tidal flow which changes its direction twice a day. However, there is one defect in the Darrieus turbine; its small starting torque. Once it stops, a Darrieus turbine is hard to re-start until a fairly fast current is exerted on it. To improve the starting torque of the Darrieus turbine used for tidal power generation, a hybrid turbine, composed of a Darrieus turbine and a Savonius rotor is proposed. Hydrodynamic characteristics of a semi-circular section used for the Savonius bucket were measured in a wind tunnel. The torque of a two bucket Savonius rotor was measured in a circulating water channel, where four different configurations of the bucket were compared. A combined Darrieus and Savonius turbine was tested in the circulating water channel, where the effect of the attaching angle between Darrieus wing and Savonius rotor was studied. Finally, power generation experiments using a 48 pole electric generator were conducted in a towing tank and the power coefficients were compared with the results of experiments obtained in the circulating water channel.

  6. Automated detection of discourse segment and experimental types from the text of cancer pathway results sections.

    Science.gov (United States)

    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

  7. Development of A Super High Speed Permanent Magnet Synchronous Motor (PMSM Controller and Analysis of The Experimental Results

    Directory of Open Access Journals (Sweden)

    Limei Zhao

    2005-02-01

    Full Text Available This paper presents the design and implementation of a DSP-based controller for a super high-speed (>80,000 rpm permanent magnet synchronous motor (PMSM. The PMSM is a key component of the centrifugal compressor drive of a reverse Brayton cryocooler that is currently under development for NASA and Florida Solar Energy Center. The design of the PMSM open-loop control is presented. Experimental results with open-loop control schemes are presented. System optimization and analysis are also illustrated. They verify the effectiveness of the controller design and the optimization scheme.

  8. Analysis and experimental results of a single-stage high-power-factor electronic ballast based on flyback converter

    Energy Technology Data Exchange (ETDEWEB)

    Calleja, A.J.; Alonso, J.M.; Lopez, E.; Ribas, J.; Martinez, J.A.; Rico-Secades, M.

    1999-11-01

    A new single-stage high-power-factor electronic ballast based on a flyback converter is presented in this paper. The ballast is able to supply a fluorescent lamp assuring a high-input power factor for the utility line. Other features are lamp power regulation against line voltage variations and low lamp current crest factor, both assuring long lamp life. The ballast is analyzed at steady-state operation, and design equations and characteristics are obtained. Also, a procedure for the ballast design is presented. Finally, simulation and experimental results from a laboratory prototype are shown.

  9. Results of many-year subsatellite measurements of current fine structure in northeastern Black Sea

    Science.gov (United States)

    Lavrova, Olga; Krayushkin, Evgeny; Kalashnikova, Nina

    Results of subsatellite measurements of coastal currents in the shelf zone of northeastern Black Sea are presented. The measurements have been performed every year since 2006 in June and September-October months near the Gelendzhik Bay. The main instruments used are Acoustic Doppler Current Profilers (ADCP) and CTD probes. Ground and ship measurements were conducted simultaneously with satellite imaging in microwave (ASAR Envisat, ERS-2, RADARSAT-2, TerraSAR-X), visible and infrared (OLI Landsat-8, ETM+ Landsat-7, TM Landsat-5, MODIS Terra/Aqua, AVHRR NOAA) ranges. The investigations performed revealed spatial, depth and temporal variability of current direction and velocity in the shelf zone. Multiple instances of counter-currents opposing to the Ring Current were registered. In our view, they are associated with a passage of small-scale anticyclonic eddies across the region of interest. The 3D structure of the eddies in the upper quasi-uniform layer was analyzed based on ADCP data. The use of high resolution (3 m) SAR data in combination with ADCP measurements at the resolution of 0.5 m allowed us to detect a number of internal wave trains. Form ADCP and thermistors records, their amplitudes were estimated to reach 5-8 m. Joint analysis of satellite SAR and subsatellite data gave an assessment of their typical wavelength at 90-100 m. Generation mechanisms of these internal waves are suggested. Another phenomenon of interest observed in the region of the measurements is surface manifestations of ring waves near localized natural and anthropogenic generation sources. Such ring waves are most frequently found in the anchor area for ships, whose oscillations can be the source of their generation. The work was in part supported by the Russian Foundation for Basic Research (projects #14-05-00520-а, and 13-07-12017-ofi_m). SAR data from RADARSAT-2 and TerraSAR-X were obtained under SOAR RADARSAT-2/TerraSAR-X Project #5074.

  10. Current situation of depression healthcare in Spain: results of a psychiatrists' survey

    Directory of Open Access Journals (Sweden)

    Belén Martín-Águeda

    2006-12-01

    Full Text Available Objective: To analyze the current situation of healthcare for depression in Spain, according to psychiatrists opinion, and how it has evolved over the last 20 years, comparativily with the results reported in previous studies of our group. Methods: Throughout 2002, we recorded the opinions of 101 specialists in psychiatry after asking them to fill out structured questionnaires in which they rated care, clinical, therapeutic and care quality. Results: The presence of depressive disorders in healthcare is substantial, despite the high figures for "concealed epidemiology", with an increase in these last 20 years of disorders comorbid with anxiety. Currently, most patients arrive at the psychiatrist having been referred by their general practitioners (GP, as there is now less reluctance in depressive patients to such referral. In the last years there has been an increase in pharmacological treatment, with adverse effects of the drugs representing the major obstacle to non-adherence to such treatment. Selective serotonin reuptake inhibitors (SSRIs constitute the pharmacological group of choice, and are the drugs most commonly used in the treatment of depression, together with venlafaxine. Areas where there is a need for improvement are time devoted to consultation, coordination between GPs and psychiatrists, waiting lists, and resources available to Mental Health Units. Conclusions: Current situation of depression healthcare in Spain has substantially changed in recent years, improving in some aspects, thanks, in part, to the attitudes of GPs with this disorder and to evolution of pharmacological treatment.

  11. Application of a LiFePO4 Battery Energy Storage System to Primary Frequency Control: Simulations and Experimental Results

    Directory of Open Access Journals (Sweden)

    Fabio Massimo Gatta

    2016-10-01

    Full Text Available This paper presents an experimental application of LiFePO4 battery energy storage systems (BESSs to primary frequency control, currently being performed by Terna, the Italian transmission system operator (TSO. BESS performance in the primary frequency control role was evaluated by means of a simplified electrical-thermal circuit model, taking into account also the BESS auxiliary consumptions, coupled with a cycle-life model, in order to assess the expected life of the BESS. Numerical simulations have been carried out considering the system response to real frequency measurements taken in Italy, spanning a whole year; a parametric study taking into account different values of governor droop and of BESS charge/discharge rates (C-rates was also performed. Simulations, fully validated by experimental results obtained thus far, evidenced a severe trade-off between expected lifetime and overall efficiency, which significantly restricts the choice of operating parameters for frequency control.

  12. Two current experimental problems in heavy lepton physics: tau decay modes and close mass pairs

    Energy Technology Data Exchange (ETDEWEB)

    Perl, M.L.

    1987-08-01

    This paper investigates tau lepton decay modes and close-mass lepton pairs. The major part of the paper discusses branching functions from experimental and theoretical viewpoints. Finally, the lack of experimental signatures of close-mass lepton pairs are reviewed. 15 refs., 2 figs., 11 tabs. (JDH)

  13. Results of Current Density Distribution Mapping in PEM Fuel Cells Dependent on Operation Parameters

    Directory of Open Access Journals (Sweden)

    Zbigniew A. Styczynski

    2013-07-01

    Full Text Available This paper presents in situ measurements of a newly developed current density measurement system for proton exchange membrane fuel cells (PEMFC. While the functional principle and technical evaluation of the measurement system were presented in a previous paper, this paper analyzes the influence of various operation parameters, including multiple start-stop operation, at the anode, cathode and cooling locations on the distribution and long-term development of the current density. The system was operated for 500 h over two years with long periods of inactivity between measurements. The measurement results are evaluated and provide additional information on how to optimize the operation modes of fuel cells, including the start and stop of such systems as well as the water balance.

  14. Experimental Investigation of an Automobile Air-Conditioning System using Integrated Brushless Direct Current Motor Rotary Compressor

    Directory of Open Access Journals (Sweden)

    Sukri M.F.

    2016-01-01

    Full Text Available The present study presents an experimental investigation on the effect of condenser air inlet temperature and dimensionless parameter of X on the performance of automobile air-conditioning (AAC system using integrated brushless direct current motor-rotary compressor and electronic expansion valve. The other components of AAC system are from original component of AAC system used for medium size passenger car. The experimental results showed that the increment of the condenser air inlet temperature and X caused an increase in condensing temperature, cooling capacity and compressor work, while decreasing the coefficient of performance (COP. Meanwhile, the evaporating temperature increase with the increment of condenser air inlet temperature, but decrease with decrement of X. In general, AAC system have to work at higher value of X in order to produce more cooling capacity, thereby increment in compressor work also occurs due to energy balance. However, at higher value of X, the COP of the system dropped due to dominant increase in compressor power, as opposed to a rise in cooling capacity. Due to this reason, the best operation of this compressor occurs at X = 4.96 for constant T5 (35ºC, or at T5 = 30ºC for constant X (4.96.

  15. How modeling can reconcile apparently discrepant experimental results: the case of pacemaking in dopaminergic neurons.

    Directory of Open Access Journals (Sweden)

    Guillaume Drion

    2011-05-01

    Full Text Available Midbrain dopaminergic neurons are endowed with endogenous slow pacemaking properties. In recent years, many different groups have studied the basis for this phenomenon, often with conflicting conclusions. In particular, the role of a slowly-inactivating L-type calcium channel in the depolarizing phase between spikes is controversial, and the analysis of slow oscillatory potential (SOP recordings during the blockade of sodium channels has led to conflicting conclusions. Based on a minimal model of a dopaminergic neuron, our analysis suggests that the same experimental protocol may lead to drastically different observations in almost identical neurons. For example, complete L-type calcium channel blockade eliminates spontaneous firing or has almost no effect in two neurons differing by less than 1% in their maximal sodium conductance. The same prediction can be reproduced in a state of the art detailed model of a dopaminergic neuron. Some of these predictions are confirmed experimentally using single-cell recordings in brain slices. Our minimal model exhibits SOPs when sodium channels are blocked, these SOPs being uncorrelated with the spiking activity, as has been shown experimentally. We also show that block of a specific conductance (in this case, the SK conductance can have a different effect on these two oscillatory behaviors (pacemaking and SOPs, despite the fact that they have the same initiating mechanism. These results highlight the fact that computational approaches, besides their well known confirmatory and predictive interests in neurophysiology, may also be useful to resolve apparent discrepancies between experimental results.

  16. Results of Numerical Modeling and Experimental Activities in Preparation of the Maxus-5 Experiment

    Science.gov (United States)

    Bassano, Edmondo; Castagnolo, Dario; Albano, Floriana; Fortezza, Raimondo

    2002-01-01

    The present paper describes numerical and experimental research activities carried out at MARS center for the preparation of an experiment on the Marangoni migration of a dissolving drop, composed by a liquid binary mixture having a miscibility gap. The paper integrates the results already presented in the previous congress, the emphasis is set on the determination of the parameters to be used for the MAXUS 5 sounding rocket mission, which is scheduled for spring 2003. Level set technique has been used for the calculation of the non-steady thermo-solutal capillary flow evolution in a bounded medium.Migration velocities and volume variation are calculated for different Marangoni numbers. The results of the numerical simulations provide the determination of drop radii and temperature gradients to be used during 12 minutes of low gravity, as provided by a MAXUS rocket. Experimental results provide accurate information on the refraction index gradient variation, due to the improvement of the interpretation of the fringe pattern. These results have allowed us to determine the optical parameters that optimize the Wollaston interferometer features. Comparison between numerical and experimental results shows a good agreement.

  17. Quality metrics currently used in academic radiology departments: results of the QUALMET survey.

    Science.gov (United States)

    Walker, Eric A; Petscavage-Thomas, Jonelle M; Fotos, Joseph S; Bruno, Michael A

    2017-03-01

    We present the results of the 2015 quality metrics (QUALMET) survey, which was designed to assess the commonalities and variability of selected quality and productivity metrics currently employed by a large sample of academic radiology departments representing all regions in the USA. The survey of key radiology metrics was distributed in March-April of 2015 via personal e-mail to 112 academic radiology departments. There was a 34.8% institutional response rate. We found that most academic departments of radiology commonly utilize metrics of hand hygiene, report turn around time (RTAT), relative value unit (RVU) productivity, patient satisfaction and participation in peer review. RTAT targets were found to vary widely. The implementation of radiology peer review and the variety of ways in which peer review results are used within academic radiology departments, the use of clinical decision support tools and requirements for radiologist participation in Maintenance of Certification also varied. Policies for hand hygiene and critical results communication were very similar across all institutions reporting, and most departments utilized some form of missed case/difficult case conference as part of their quality and safety programme, as well as some form of periodic radiologist performance reviews. Results of the QUALMET survey suggest many similarities in tracking and utilization of the selected quality and productivity metrics included in our survey. Use of quality indicators is not a fully standardized process among academic radiology departments. Advances in knowledge: This article examines the current quality and productivity metrics in academic radiology.

  18. Treatment of gastric outlet obstruction that results fromunresectable gastric cancer: Current evidence

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Malignant gastric outlet obstruction (GOO) is a commoncondition that results from locally advanced malignanciesin the upper gastrointestinal tract, such aspancreatic, gastric, and other carcinomas. Two typesof procedures for malignant GOO, namely, gastrojejunostomy(GJ) with laparotomy or a laparoscopicapproach and endoscopic stenting (ES), are currentlyavailable. Although numerous previous reports haveclarified the benefits and drawbacks of each procedure,whether GJ or ES should be used in patients with GOOthat results from gastric cancer who may have a longerlife expectancy than patients with other malignancieshas not been determined. In this review, which focuseson gastric cancer-induced GOO, we analyzed the twosystematic reviews and a meta-analysis that comparedGJ and ES and outlined the current status of GOOtreatment. We also provide an updated review thatincludes laparoscopic GJ. Various data from 13 studiesin one review and 6 studies in another review wereanalyzed. Although the main results of the presentreview indicated that both GJ and ES were efficacioustreatments in patients with GOO that resulted fromgastric cancer, current evidence suggests that GJ maybe the preferable procedure given its good performancestatus and improved prognosis in gastric cancer patients.

  19. Iterative reconstruction for quantitative computed tomography analysis of emphysema: consistent results using different tube currents

    Directory of Open Access Journals (Sweden)

    Yamashiro T

    2015-02-01

    Full Text Available Tsuneo Yamashiro,1 Tetsuhiro Miyara,1 Osamu Honda,2 Noriyuki Tomiyama,2 Yoshiharu Ohno,3 Satoshi Noma,4 Sadayuki Murayama1 On behalf of the ACTIve Study Group 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa, Japan; 2Department of Radiology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan; 3Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan; 4Department of Radiology, Tenri Hospital, Tenri, Nara, Japan Purpose: To assess the advantages of iterative reconstruction for quantitative computed tomography (CT analysis of pulmonary emphysema. Materials and methods: Twenty-two patients with pulmonary emphysema underwent chest CT imaging using identical scanners with three different tube currents: 240, 120, and 60 mA. Scan data were converted to CT images using Adaptive Iterative Dose Reduction using Three Dimensional Processing (AIDR3D and a conventional filtered-back projection mode. Thus, six scans with and without AIDR3D were generated per patient. All other scanning and reconstruction settings were fixed. The percent low attenuation area (LAA%; < -950 Hounsfield units and the lung density 15th percentile were automatically measured using a commercial workstation. Comparisons of LAA% and 15th percentile results between scans with and without using AIDR3D were made by Wilcoxon signed-rank tests. Associations between body weight and measurement errors among these scans were evaluated by Spearman rank correlation analysis. Results: Overall, scan series without AIDR3D had higher LAA% and lower 15th percentile values than those with AIDR3D at each tube current (P<0.0001. For scan series without AIDR3D, lower tube currents resulted in higher LAA% values and lower 15th percentiles. The extent of emphysema was significantly different between each pair among scans when not using AIDR3D (LAA%, P<0.0001; 15th percentile, P<0.01, but was not

  20. JT-60 negative ion beam NBI apparatus. Present state of its construction and initial experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, Masaaki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1997-02-01

    The NBI (Neutral Beam Injection) apparatus used for negative ion at first in the world, has an aim to actually prove heating and electric current drive with high density plasma at the JT-60 and to constitute physical and technical bases for selection and design of heating apparatus of ITER (International Thermal Nuclear Fusion Experimental Reactor). Construction of 500 KeV negative ion NBI apparatus for the JT-60 started to operate on 1993 was completed at March, 1996. On the way, at a preliminary test on forming and acceleration of the negative ion beam using a portion of this apparatus, 400 KeV and 13.5 A/D of the highest deuterium negative ion beam acceleration in the world was obtained successfully, which gave a bright forecasting of the plasma heating and electric current drive experiment using the negative ion NBI apparatus. After March, 1996, some plans to begin beam incident experiment at the JT-60 using the negative ion NBI apparatus and to execute the heating and electric current drive experiment at the JT-60 under intending increase of beam output are progressed. (G.K.)

  1. Test result communication in primary care: a survey of current practice.

    Science.gov (United States)

    Litchfield, Ian; Bentham, Louise; Lilford, Richard; McManus, Richard J; Hill, Ann; Greenfield, Sheila

    2015-11-01

    The number of blood tests ordered in primary care continues to increase and the timely and appropriate communication of results remains essential. However, the testing and result communication process includes a number of participants in a variety of settings and is both complicated to manage and vulnerable to human error. In the UK, guidelines for the process are absent and research in this area is surprisingly scarce; so before we can begin to address potential areas of weakness there is a need to more precisely understand the strengths and weaknesses of current systems used by general practices and testing facilities. We conducted a telephone survey of practices across England to determine the methods of managing the testing and result communication process. In order to gain insight into the perspectives from staff at a large hospital laboratory we conducted paired interviews with senior managers, which we used to inform a service blueprint demonstrating the interaction between practices and laboratories and identifying potential sources of delay and failure. Staff at 80% of practices reported that the default method for communicating normal results required patients to telephone the practice and 40% of practices required that patients also call for abnormal results. Over 80% had no fail-safe system for ensuring that results had been returned to the practice from laboratories; practices would otherwise only be aware that results were missing or delayed when patients requested results. Persistent sources of missing results were identified by laboratory staff and included sample handling, misidentification of samples and the inefficient system for collating and resending misdirected results. The success of the current system relies on patients both to retrieve results and in so doing alert staff to missing and delayed results. Practices appear slow to adopt available technological solutions despite their potential for reducing the impact of recurring errors in the

  2. An experimental investigation of the dynamics of submarine leveed channel initiation as sediment-laden density currents experience sudden unconfinement

    Energy Technology Data Exchange (ETDEWEB)

    Rowland, Joel C [Los Alamos National Laboratory; Hilley, George E [STANFORD UNIV; Fildani, Andrea [CHEVRON ETC

    2009-01-01

    Leveed submarine channels play a critical role in the transfer of sediment from the upper continental slopes to interslope basins and ultimately deepwater settings. Despite a reasonable understanding of how these channels grow once established, how such channels initiate on previously unchannelized portions of the seafloor remains poorly understood. We conducted a series of experiments that elucidate the influence of excess density relative to flow velocity on the dynamics of, and depositional morphologies arising from, density currents undergoing sudden unconfinement across a sloped bed. Experimental currents transported only suspended sediment across a non-erodible substrate. Under flow conditions ranging from supercritical to subcritical (bulk Richardson numbers of 0.02 to 1.2) our experiments failed to produce deposits resembling or exhibiting the potential to evolve into self-formed leveed channels. In the absence of excess density, a submerged sediment-laden flow produced sharp crested lateral deposits bounding the margins of the flow for approximately a distance of two outlet widths down basin. These lateral deposits terminated in a centerline deposit that greatly exceeded marginal deposits in thickness. As excess density increased relative to the outlet velocity, the rate of lateral spreading of the flow increased relative to the downstream propagation of the density current, transitioning from a narrow flow aligned with the channel outlet to a broad radially expanding flow. Coincident with these changes in flow dynamics, the bounding lateral deposits extended for shorter distances, had lower, more poorly defined crests that were increasingly wider in separation than the initial outlet, and progressively became more oblong rather than linear. Based on our results, we conclude that leveed channels cannot initiate from sediment-laden density currents under strictly depositional conditions. Partial confinement of these currents appears to be necessary to

  3. Test Results For a 25-m Prototype Fault Current Limiting HTS Cable for Project Hydra

    Energy Technology Data Exchange (ETDEWEB)

    Rey, Christopher M [ORNL; Duckworth, Robert C [ORNL; Demko, Jonathan A [ORNL; Ellis, Alvin R [ORNL; Gouge, Michael J [ORNL; James, David Randy [ORNL; Tuncer, Enis [ORNL

    2010-01-01

    The Oak Ridge National Laboratory (ORNL) has tested a 25-m long prototype High Temperature Superconducting (HTS) cable with inherent Fault-Current Limiting (FCL) capability at its recently upgraded HTS cable test facility in Oak Ridge, TN. The HTS-FCL cable and terminations were designed and fabricated by Ultera, which is a joint venture of Southwire and nkt cables with FCL features and HTS wire provided by American Superconductor Corporation. The overall project is sponsored by the U.S. Department of Homeland Security. The ultimate goal of the 25-m HTS-FCL cable test program was to verify the design and ensure the operational integrity for the eventual installation of a ~ 200-m fully functional HTS-FCL cable in the Consolidated Edison electric grid located in downtown New York City. The 25-m HTS-FCL cable consisted of a three-phase (3- ) Triax design with a cold dielectric between the phases. The HTS-FCL cable had an operational voltage of 13.8 kV phase-to-phase and an operating current of 4000 Arms per phase, which is the highest operating current to date of any HTS cable. The 25-m HTS-FCL cable was subjected to a series of cryogenic and electrical tests. Test results from the 25-m HTS-FCL cable are presented and discussed.

  4. Experimental and numerical examination of eddy (Foucault) currents in rotating micro-coils: Generation of heat and its impact on sample temperature.

    Science.gov (United States)

    Aguiar, Pedro M; Jacquinot, Jacques-François; Sakellariou, Dimitris

    2009-09-01

    The application of nuclear magnetic resonance (NMR) to systems of limited quantity has stimulated the use of micro-coils (diameter Foucault (eddy) currents, which generate heat. We report the first data acquired with a 4mm MACS system and spinning up to 10kHz. The need to spin faster necessitates improved methods to control heating. We propose an approximate solution to calculate the power losses (heat) from the eddy currents for a solenoidal coil, in order to provide insight into the functional dependencies of Foucault currents. Experimental tests of the dependencies reveal conditions which result in reduced sample heating and negligible temperature distributions over the sample volume.

  5. Current regional stress field and the resultant crustal deformation in SE Korea and their tectonic implication

    Science.gov (United States)

    Kim, M. C.; Cho, H.; Son, M.

    2014-12-01

    To determine current regional stress field and to characterize the resultant crustal deformation in SE Korea, Quaternary fault, focal mechanism, and geotechnical in-situ stress data were synthetically analyzed. The Quaternary faults are extensively observed along major inherited fault zones and show compatible orientations with general trends of the inherited faults. Most of the Quaternary faults have a top-to-the-west thrust geometry and kinematics and show a tendency of upward-decreasing dip angle and upward-narrowing gouge zone. Slip-sense indicators and paleo-stress field reconstructions indicate that the faults resulted from reverse or transpressional faulting under an E-W compression. All the magnetic fabrics (AMS) of the fault gouges also indicate the prevailing reverse-slip faulting under an ENE-WNW compression. The dominant oblate magnetic fabrics parallel to fault plane and the degrees of anisotropy increasing in proportion to their oblatenesses indicate that the fabrics have formed by a progressive deformation due to continuous simple shear during the last reactivation stage as reverse faulting. The focal mechanism study in and around the Korean Peninsula show the horizontally clustered P-axes in ENE-WSW direction and the girdle-distributed T-axes in NNW trend. The geotechnical in-situ stress data in south Korea also show NE- or ENE-trending maximum horizontal stress. The current crustal deformation in Korea thus can be characterized by contractional structures produced under a regional E-W or ENE-WSW compression stress field, and most of the Quaternary faults resulted from the local re-activation of appropriately oriented inherited major faults. Considering the tectonic setting and structural features in Asia during the Neogene, the current stress regime is interpreted to have been caused by the cooperation of westward shallow subduction of Pacific Plate and collision of Indian and Eurasian continents since about 5-3.5 Ma.

  6. Experimental results and numerical simulations for transonic flow over the ONERA M4R model

    Directory of Open Access Journals (Sweden)

    Marius Gabriel COJOCARU

    2013-06-01

    Full Text Available This paper presents a comparison between experimental results of transonic flow over the ONERA M4R calibration model obtained in the INCAS Trisonic wind tunnel and the numerical results. The first purpose, emphasized in this paper is to compare and validate the computational fluid dynamics (CFD techniques for internal transonic flows and to try to find the most suitable numerical methodology for these flows in both accuracy and computational resources. The second purpose is to develop a general method in experimental data correction and flight Reynolds extrapolation, using numerical simulations for both global and local pressure coefficients, as a replacement for the classical vortex lattices based method. That will be developed in a future paper. Besides the computational work, the periodic wind tunnel calibration is required as a quality insurance operation and a numerical model is developed such that future hardware modifications to be included and their impact to be properly considered.

  7. Development of Si-based electrical biosensors: Simulations and first experimental results

    Directory of Open Access Journals (Sweden)

    Marco Favetta

    2015-12-01

    Full Text Available In this work, we simulated and experimentally assessed the possibility to detect, through electrical transduction, hybridization of DNA molecules on MOS-like devices, having different dielectrics: SiO2, Si3N4 and SiO2/Si3N4/SiO2 (ONO. The electrical characterization was performed after the various functionalization steps, consisting of dielectric activation, silanization, DNA spotting and anchoring, and after the hybridization process, to test the devices effectiveness as DNA recognition biosensors. The experimental results were used to validate device simulations. The comparison shows the ability to determine a priori the DNA probe density needed to maximize the response. The results confirm that the structures analyzed are sensitive to the immobilization of DNA and its hybridization.

  8. Parallel Path Magnet Motor: Development of the Theoretical Model and Analysis of Experimental Results

    Science.gov (United States)

    Dirba, I.; Kleperis, J.

    2011-01-01

    Analytical and numerical modelling is performed for the linear actuator of a parallel path magnet motor. In the model based on finite-element analysis, the 3D problem is reduced to a 2D problem, which is sufficiently precise in a design aspect and allows modelling the principle of a parallel path motor. The paper also describes a relevant numerical model and gives comparison with experimental results. The numerical model includes all geometrical and physical characteristics of the motor components. The magnetic flux density and magnetic force are simulated using FEMM 4.2 software. An experimental model has also been developed and verified for the core of switchable magnetic flux linear actuator and motor. The results of experiments are compared with those of theoretical/analytical and numerical modelling.

  9. Overall Buckling and Wringkling of Debonded Sandwich Beams: Finite Element and Experimental Results

    Directory of Open Access Journals (Sweden)

    Bambang K. Hadi

    2006-05-01

    Full Text Available Overall buckling and wrinkling of debonded sandwich beams under compressive loads were analyzed by both finite element and experimental methods. In the finite element method, a quarter and a half models of the specimens were analyzed. It shows that a quarter model is not adequate to analyze buckling of debonded sandwich beams, since it will disregard overall buckling mode that may occur in sandwich beams having compressive loads. At least a half model should be used to analyze buckling of sandwich beams. A finite element program UNA was used extensively to analyze the buckling loads. Experimental buckling of sandwich beams was carried out using a compression testing machine. Two LVDTs were used to measure deflections of the specimen during experimental loading. The loads were measured using load cells available in the machine. Specimens having core thickness of 45 and 75 mm were tested to represent overall and wrinkling modes respectively. The delamination lengths were 20, 60 and 80 mm, which represent 10, 30 and 40% of the beam length. The results show that the differences between experimental and finite element methods were less than 10%. Both overall buckling and wrinkling modes were shown in these specimens.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  11. Recent experimental results and developments on the resistive plate chambers for the CMS experiment

    CERN Document Server

    Altieri, S; Bruno, G; Guida, R; Merlo, M; Ratti, S P; Riccardi, C; Torre, P; Vitulo, P; Abbrescia, M; Colaleo, A; Iaselli, Giuseppe; Loddo, F; Maggi, M; Marangelli, B; Natali, S; Nuzzo, S; Pugliese, G; Ranieri, A; Romano, F

    2001-01-01

    Resistive plate chambers (RPC) have been chosen as dedicated trigger detectors for the CMS experiment at the LHC. The expected severe operating conditions have required an intense research and development activity on these detectors over the past years. Experimental results on overall performance of large chambers, rate capability, ageing and photon sensitivity are reviewed. In all of these tests the detector has proven to achieve good enough performance for successful use at the LHC. (6 refs).

  12. Parallel Guided Local Search and Some Preliminary Experimental Results for Continuous Optimization

    Directory of Open Access Journals (Sweden)

    Nasser Tairan

    2014-02-01

    Full Text Available This paper proposes a Parallel Guided Local Search (PGLS framework for continuous optimization. In PGLS, several guided local search (GLS procedures (agents are run for solving the optimization problem. The agents exchan ge information for speeding up the search. For example, the information exchanged could be kno wledge about the landscape obtained by the agents. The proposed algorithm is applied to co ntinuous optimization problems. The preliminary experimental results show that the algo rithm is very promising .

  13. Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results

    OpenAIRE

    2004-01-01

    A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerge...

  14. Experimental results and model simulation of the non-fall top

    OpenAIRE

    古川, 不二夫; 藤川, 卓爾

    2007-01-01

     The ordinary top spins for about 10 minutes. The spinning duration of the non-fall top is prolonged to more than 100 minutes in a vacuum, because friction loss due to air viscosity is reduced and the friction at fulcrum of the top's stem is mainly responsible for spinning loss. This paper introduces experimental results of non-fall tops and simulation using a simplified model.

  15. Electron emission at very low electron impact energy: experimental and Monte-Carlo results

    CERN Document Server

    Belhaj, M.; Jbara, O.; Puech, J.; Balcon, N.; Payan, D.

    2013-04-22

    The behaviour of electron emission under electron impact at very low energy is of great importance in many applications such as high energy physics, satellites, nuclear reactors, etc. However the question of the total electron reflectivity is still in discussion. Our experimental and theoretical studies show that the total reflectivity at very low energy is far from being an obvious fact. Moreover, our results show that the yield is close to zero and not equal to one for low energy incident electron.

  16. Kinematic Viscosities for Ether + Alkane Mixtures: Experimental Results and UNIFAC-VISCO Parameters

    Science.gov (United States)

    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.

  17. A digital computer propulsion control facility: Description of capabilities and summary of experimental program results

    Science.gov (United States)

    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. Defining Dynamic Characteristics of Multilink Pendulum System with Comparison of the Calculated and Experimental Results

    Directory of Open Access Journals (Sweden)

    V. A. Gribkov

    2015-01-01

    Full Text Available We consider the multilink pendulum system consisting of six physical pendulums. A pendulum (carrier has inertia parameters, which significantly exceed the remaining (carried ones placed on the carrier. In addition to the system under analysis, in particular, the paper presents a design scheme for a two-stage liquid fuel rocket using pendulums as the analogues of fluctuating fuel. Pendulum models also find application to solve problems of stabilization of space tether systems. The objective of the study is to determine dynamic characteristics of the said sixmembered pendulum system, as well as to identify specific dynamic properties inherent in objects of this kind. Dynamic characteristics of the system are determined by calculations. A physical model of the pendulum allowed us to compare the calculated and experimental results. To conduct the frequency tests of the pendulum model three pilot units have been created. The first two units turned out to be inappropriate for fulfilling the experimental tasks for various reasons. The third unit enabled us to obtain desirable experimental results. The "calculation–experiment” discrepancy on the natural frequencies of the pendulum model for the majority of frequencies was less than 5%. We analyzed the dynamic features of multilink pendulum systems "carried by the carrier unit links". The analysis results are applicable to the above-noted object classes of rocket and space technology.

  19. Estimating the hyperfine coupling parameters of the avian compass by comprehensively considering the available experimental results

    Science.gov (United States)

    Xu, Bao-Ming; Zou, Jian; Li, Jun-Gang; Shao, Bin

    2013-09-01

    Migratory birds can utilize the geomagnetic field for orientation and navigation through a widely accepted radical-pair mechanism. Although many theoretical works have been done, the available experimental results have not been fully considered, especially the temporary disorientation induced by the field which is increased by 30% of the geomagnetic field and the disorientation of the very weak resonant field of 15 nT. In this paper, we consider the monotonicity of the singlet yield angular profile as the prerequisite of direction sensitivity, and find that for some optimal values of the hyperfine coupling parameters (that is, the order of 10-7˜10-6 meV) the experimental results available so far can be satisfied. We also investigate the effects of two decoherence environments and demonstrate that, in order to satisfy the available experimental results, the decoherence rate should be lower than the recombination rate. Finally, we investigate the effects of the fluctuating magnetic noises and find that the vertical noise destroys the monotonicity of the profile completely, but the parallel noise preserves the monotonicity perfectly and even can enhance the direction sensitivity.

  20. Estimating the HF coupling parameters of the avian compass by comprehensively considering the available experimental results

    CERN Document Server

    Xu, Bao-Ming; Li, Jun-Gang; Shao, Bin

    2013-01-01

    Migratory birds can utilize the geomagnetic field for orientation and navigation through a widely accepted radical-pair mechanism. Although many theoretical works have been done the available experimental results have not been fully considered, especially, the temporary disorientation induced by the field which is increased by 30% of geomagnetic field and the disorientation of the very weak resonant field of $15nT$. In this paper, we consider the monotonicity of the singlet yield angular profile as the prerequisite of direction sensitivity, and find that for some optimal values of the hyperfine coupling parameters, that is the order of $10^{-7}\\sim10^{-6}meV$, the experimental results available by far can be satisfied. We also investigate the effects of two decoherence environments and demonstrate that, in order to satisfy the available experimental results, the decoherence rate should be much lower than the recombination rate. Finally we investigate the effects of the fluctuating magnetic noises, and find th...

  1. The HIT-II Spherical Torus: Physics and Key Experimental Results

    Science.gov (United States)

    Redd, A. J.; Hamp, W. T.; Izzo, V. A.; Jarboe, T. R.; Nelson, B. A.; O'Neill, R. G.; Raman, R.; Sieck, P. E.; Smith, R. J.

    2004-11-01

    Discharges in the HIT-II spherical torus device [Redd et al., Phys. Plasmas 9, 2006 (2002)] can be driven by either Ohmic or Coaxial Helicity Injection (CHI) current drive. A new CHI operating regime has been explored, with toroidal plasma currents of up to 350 kA, I_p/I_TF ratios of up to 1.2, and internal probing data which may demonstrate the formation of a closed-flux core. The key to acheiving these results is the magnetic field shear in the CHI injector region, with a minimum shear necessary for current build-up. Ohmic plasma performance has also improved, with peak currents up to 300 kA, with and without transient CHI startup. The CHI startup technique [Raman et al., Phys. Plasmas 11, 2565 (2004)] provides more robust discharges, with a wider operating space and more efficient use of the transformer Volt-seconds, than unassisted Ohmic. Finally, CHI can be used to enhance an Ohmic plasma current without significantly degrading the quality of the discharge. Results will be presented for each HIT--II operating regime, including empirical performance scalings and applicable parametric operating spaces.

  2. First results from solid state neutral particle analyzer on experimental advanced superconducting tokamak

    Science.gov (United States)

    Zhang, J. Z.; Zhu, Y. B.; Zhao, J. L.; Wan, B. N.; Li, J. G.; Heidbrink, W. W.

    2016-11-01

    Full function integrated, compact solid state neutral particle analyzers (ssNPA) based on absolute extreme ultraviolet silicon photodiode have been successfully implemented on the experimental advanced superconducting tokamak to measure energetic particle. The ssNPA system has been operated in advanced current mode with fast temporal and spatial resolution capabilities, with both active and passive charge exchange measurements. It is found that the ssNPA flux signals are increased substantially with neutral beam injection (NBI). The horizontal active array responds to modulated NBI beam promptly, while weaker change is presented on passive array. Compared to near-perpendicular beam, near-tangential beam brings more passive ssNPA flux and a broader profile, while no clear difference is observed on active ssNPA flux and its profile. Significantly enhanced intensities on some ssNPA channels have been observed during ion cyclotron resonant heating.

  3. The results of decontamination and decommissioning of experimental DUPIC equipment at PIEF 9405 hot cell

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H. H.; Park, J. J.; Shin, J. M.; Cho, K. H.; Yang, M. S.; Lee, E. P. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-02-01

    The characterization experiment for powder and sintered fuel had been performed using about 1 kg-U spent PWR fuel at No. 9405 hot-cell in PIEF(Post Irradiated Experiment Facility) since early in 1999. Currently, the experiments in PIEF have been completed. Since all DUPIC equipment in hot-cell are contaminated by high radioactive material, the decontamination and dismantlement must be performed remotely by M/S manipulator. During the radioactive waste packing and transportation, the reduction method of radiation exposure has to be considered. This report describes the basic plan for dismantlement/decontamination of the characterization equipment (power and sintered fuel). And methods of measurement/packing/transportation, method of dismantlement/decontamination of the experimental apparatus and the reduction method of radiation dose exposure, etc. are explained in order. 7 refs., 42 figs., 10 tabs. (Author)

  4. Faculty perceptions of the strengths, weaknesses and future prospects of the current medical undergraduate experimental physiology curriculum in Gujarat, India.

    Science.gov (United States)

    Paralikar, Swapnil; Shah, Chinmay

    2015-01-01

    Over the past several years, an opinion has emerged in India that the current practical curricula in medical schools fail to meet many of the objectives for which they were instituted. Hence, this study has assessed the perception of physiology faculty members regarding the current experimental physiology curriculum in one Indian state, Gujarat. The faculty were of the opinion that many of the topics currently taught in experimental physiology (amphibian nerve-muscle and heart muscle experiments) were outdated and clinically irrelevant: Therefore, the faculty advocated that duration of teaching time devoted to some of these topics should be reduced and topics with clinical relevance should be introduced at the undergraduate level. The faculty also felt that more emphasis should be laid on highlighting the clinical aspect related to each concept taught in experimental physiology . Moreover, a majority of faculty members were in favour of replacing the current practice in Gujarat of teaching experimental physiology only by explanation of graphs obtained from experiments conducted in the previous years, with computer assisted learning in small groups.

  5. Theoretical and Experimental Study of the Primary Current Distribution in Parallel-Plate Electrochemical Reactors

    Science.gov (United States)

    Vazquez Aranda, Armando I.; Henquin, Eduardo R.; Torres, Israel Rodriguez; Bisang, Jose M.

    2012-01-01

    A laboratory experiment is described to determine the primary current distribution in parallel-plate electrochemical reactors. The electrolyte is simulated by conductive paper and the electrodes are segmented to measure the current distribution. Experiments are reported with the electrolyte confined to the interelectrode gap, where the current…

  6. Experimental Phenomena of Improved Ohmic Confinement Induced by Modulated Toroidal Current on the HT-7 Tokamak

    Institute of Scientific and Technical Information of China (English)

    毛剑珊; 罗家融; P.Phillips; 赵君煜; 揭银先; 吴振伟; 胡立群; 李建刚

    2002-01-01

    The phenomena of improved ohmic confinement have been observed during the modulation of the toroidal curranton the Hefei superconducting Tokamak-7 (HT-7). In the experiment, the programming ohmic heating field wasmodulated. A toroidal frequency-modulated current induced by modulated loop voltage was added on the plasmaequilibrium current. The ratio of ac amplitude of the plasma current to the main plasma current is about 12-30%.These improved plasma confinement phenomena include the facts that the average electron density and the centralelectron temperature both increase, the Dα radiation from the edge is reduced, the magnetohydrodynamics isobviously suppressed by oscillating plasma current, eand the global energy confinement time increases by 27-45%o.It is found that the faster the modulation is, the more effective the improved ohmic confinement phase.

  7. Experimental Results of NWCF Run H4 Calcine Dissolution Studies Performed in FY-98 and -99

    Energy Technology Data Exchange (ETDEWEB)

    Garn, Troy Gerry; Herbst, Ronald Scott; Batcheller, Thomas Aquinas; Sierra, Tracy Laureena

    2001-08-01

    Dissolution experiments were performed on actual samples of NWCF Run H-4 radioactive calcine in fiscal years 1998 and 1999. Run H-4 is an aluminum/sodium blend calcine. Typical dissolution data indicates that between 90-95 wt% of H-4 calcine can be dissolved using 1gram of calcine per 10 mLs of 5-8M nitric acid at boiling temperature. Two liquid raffinate solutions composed of a WM-188/aluminum nitrate blend and a WM-185/aluminum nitrate blend were converted into calcine at the NWCF. Calcine made from each blend was collected and transferred to RAL for dissolution studies. The WM-188/aluminum nitrate blend calcine was dissolved with resultant solutions used as feed material for separation treatment experimentation. The WM-185/aluminum nitrate blend calcine dissolution testing was performed to determine compositional analyses of the dissolved solution and generate UDS for solid/liquid separation experiments. Analytical fusion techniques were then used to determine compositions of the solid calcine and UDS from dissolution. The results from each of these analyses were used to calculate elemental material balances around the dissolution process, validating the experimental data. This report contains all experimental data from dissolution experiments performed using both calcine blends.

  8. SIMULATION AND EXPERIMENTAL RESULTS FOR THE CLOSED LOOP CONTROLLED DC TO DC FORWARD CONVERTER

    Directory of Open Access Journals (Sweden)

    A. Palamalai VIJAYAKUMAR

    2017-06-01

    Full Text Available A Closed loop controlled DC to DC forward converter is a requisite for the server SMPS system. High efficiency, Isolation, Steady state voltage, Transient response, High switching frequency, reduced noises and range of steady state are all necessary requirements for the forward converter. In this paper, a 40 V forward converter for charging the battery of server SMPS is proposed. The proposed converter consists of a NPC-ARS circuit for soft switching on the primary side and an isolation transformer and a rectifier structure on the secondary side. With this modified NPC-ARS circuit topology, soft switching occurs during conversion and reduces the switching loss in this system. This paper proposed the simulation of closed loop controlled circuit, for the forward converter with RCD snubber, double forward converter and the Modified forward converter are analyzed and discussed in this paper. From comparison of performance in the closed loop model, a suitable converter is proposed for the sever SMPS system. The proposed circuit achieves steady state voltage, when the disturbance occurs. A 40 V proposed circuit is designed as experimental model to verify and compare the simulation and experimental results. This paper proposed the simulation and experimental results of the forward converter.

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

    Science.gov (United States)

    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. JFIT: a framework to obtain combined experimental results through joint fits

    CERN Document Server

    AUTHOR|(CDS)2080561; Echenard, Bertrand; Latham, Thomas E

    2014-01-01

    A framework is presented for obtaining combined experimental results through joint fits of datasets from several experiments. The JFIT framework allows such fits to be performed keeping the data separated, in its original format, and using independent fitting environments, thus simplifying the process with respect to data access policies. It is based on a master-server architecture, using the network communication classes from ROOT. The framework provides an optimal way to exploit data from several experiments: it ensures that correlations are correctly taken into account and results in a better determination of nuisance parameters. Its advantages are discussed and illustrated by two examples from the domain of high energy physics.

  11. Experimental and numerical results of a high frequency rotating active magnetic refrigerator

    DEFF Research Database (Denmark)

    Lozano, Jaime; Engelbrecht, Kurt; Bahl, Christian R.H.

    2014-01-01

    Experimental results for a recently developed prototype magnetic refrigeration device at the Technical University of Denmark (DTU) were obtained and compared with numerical simulation results. A continuously rotating active magnetic regenerator (AMR) using 2.8 kg packed sphere regenerators...... and implemented in a one-dimensional numerical AMR model that includes also the parasitic losses from the prototype. The temperature span for a thermal load of 200 W as a function of frequency was measured and modelled. Moreover, the temperature span dependence on the cooling capacity as a function of cycle...

  12. Theoretical and Experimental Results of Substrate Effects on Microstrip Power Divider Designs

    Directory of Open Access Journals (Sweden)

    Suhair Mansoor Mahmood

    2011-01-01

    Full Text Available The effects of substrate materials on the design of microstrip power divider are investigated theoretically and experimentally. Three dielectric substrate materials, Duroid 3003, G10/FR4 epoxy Glass, and Duroid 3010, are chosen to be studied. A three-way two-stage power divider is designed at S-band frequency of 2.25 GHz and etched on each studied substrate separately. The substrate effects on the characteristics and performance of the microsrip circuits are studied taking into consideration the large difference in dielectric constant and the dissipation factor. The circuit designs presented here are analyzed using the Genesys CAD program and implemented and tested experimentally. The simulated and measured results are compared and discussed, and they indicate that significant changes in the characteristics of the microstrip power divider are observed.

  13. Formation of surfactant-laden drops: comparison of experimental and numerical results

    Science.gov (United States)

    Kovalchuk, Nina; Kahouadji, Lyes; Simmons, Mark; Craster, Richard; Matar, Omar; Juric, Damir; Chergui, Jalel; Shin, Seungwon

    2016-11-01

    Drop formation is ubiquitous in many industrial processes, with surfactants being commonly used to stabilise drops. Thus, understanding the regularities of drop formation and accompanying processes, such as formation of satellite droplets in the presence of surfactant is of high importance. Here we present the results of a comparative experimental and numerical study on formation of surfactant-laden drops over a range of flow rates and surfactant concentrations. The precise parameters of the surface tension isotherm for surfactants used in the experimental study are implemented in the numerical code enabling quantitative comparison between the two approaches. It is shown that the effect of surfactant depends not only on concentration, but also on the value of critical micellar concentration (cmc). The transition to the regime where satellite droplets are no longer released was observed when the flow rate exceeded a threshold value depending on surfactant concentration and cmc value. EPSRC UK Programme Grant MEMPHIS (EP/K003976/1).

  14. Current radiological techniques used to evaluate unilateral partial ureteral obstruction: an experimental rabbit study.

    Science.gov (United States)

    Yazıcı, Mehmet; Celebi, Suleyman; Kuzdan, Özgür; Koçan, Hüseyin; Ayyıldız, Halil Suat; Bayrak, İlkay Koray; Bilgici, Meltem Ceyhan; Yapıcı, Oktay; Kefeli, Mehmet; Arıtürk, Ender

    2015-07-01

    The aim of this study was to evaluate functional and prognostic benefits of Doppler ultrasonography (DU), diuretic renal scintigraphy (DRS), and magnetic resonance urography (MRU) during diagnosis and follow-up of ureteropelvic junction obstruction (UPJO) and to examine apoptosis rates caused by UPJO in an experimental rabbit model. Twenty-four rabbits were divided randomly into two groups. The left kidneys of 15 rabbits from the first group underwent Ulm-Miller surgery to create UPJO, whereas the left kidneys of nine rabbits from the second group underwent sham surgery. A pressure flow study (Whitaker's test) was done during postoperative week 6. Based on the Whitaker test, the DU, DRS, and MRU findings were compared. The number of apoptotic renal cells was counted after death. The Whitaker test run during postoperative week 6 revealed obstructions in 15 rabbits from group 1; the nine rabbits of the sham group had no obstructions. Sensitivity and specificity of DRS were 93.3 and 88.8 %, respectively, and those of MRU were 93.3 and 88.8 %, respectively. The postoperative mean RI values were significantly higher than the preoperative values, associated with sensitivity of 86.6 % and specificity of 77.5 % for detecting UPJO. DRS, MRU, and RI could not predict UPJO in one (8 %), one (8 %), and two (16 %) kidneys, respectively. Likelihood ratio (LR) was 8.4 for MRU and scintigraphy, while for RI, LR was 3.9. Pathology specimens revealed that all kidneys with UPJO underwent apoptosis, and the number of apoptotic cells was significantly higher on the UPJO-created side than on the contralateral and in the sham group (p < 0.05). No test predicted all apoptosis related to UPJO. The RI, DRS, and DMRU results correlated with the pressure flow results for detecting UPJO. No single radiological technique predicted all initial UPJO-created kidneys that concluded with apoptosis. Further studies are required to seek with better methods for diagnosing an obstruction or to define a

  15. The entrapment of organic dyes into sol gel matrix: Experimental results and modeling for photonic applications

    Science.gov (United States)

    Costa, Sheila C. S.; Gester, Rodrigo M.; Guimarães, Jeconias R.; Amazonas, Jarlesson G.; Nero, Jordan Del; Silva, Sidicleia B. C.; Galembeck, Andre

    2008-05-01

    To better understand the electronic absorption spectra in the UV-vis region of the methyl red (MR) dye in its anionic, isoelectronic and zwitterionic forms in aqueous solution, high level sequential-Monte Carlo/quantum mechanics (s-MC/QM) methodology was performed and compared to experimental measurements. The theoretical procedure consists in treating the solute-solvent system separately using classical MC simulations to build the MR aqueous solution and then, the MC structures are treated by quantum approaches. Thus, the solvent effects were investigated including on the INDO/CI-S calculations initially the micro and further the first hydration shells. As we excepted the absorption spectra are characterized by a strong band placed in the region of lowest energies. To the basic form we computed shoulders at 434.33 ± 0.09 and 436.34 ± 0.56 nm corresponding to the micro and first hydration shells, respectively. Our experimental measurements display this shoulder at 431 nm. Under acidic forms (isoelectronic and zwitterionic), we computed the red shift in relation to the basic compound. To the isoelectronic structure we found the absorption maximum located at 485.80 ± 0.34 and 480.66 ± 0.67 nm to the micro and first shells, respectively. The experimental prediction of 513 nm is in good agreement with theoretical result. Finally the zwitterionic form we did not obtain a micro layer, therefore we used only the first shell. Our theoretical results are converged to 502.13 ± 0.79 nm in good concordance with the experimental confirmation of 511 nm. These samples were optically transparent, hard and resistant to dye leaching and to chemical attacks, being promising materials to be used in optical devices.

  16. Bad results obtained from the current public health policies and recommendations of hydration

    Directory of Open Access Journals (Sweden)

    Ismael San Mauro Martín

    Full Text Available Introduction: Achieving an adequate intake of water is crucial within a balanced diet. For that purpose, dietary guidelines for healthy eating and drinking are an important consideration and need to be updated and disseminated to the population. Aim: We aimed to evaluate the liquid intake habits of a Mediterranean and Latin American population (Spain-Portugal and Mexico-Uruguay and if they support the current recommendations of hydration by the EFSA. Methods: A record of fluid intake was obtained from 1,168 participants from 4 countries above; and then compared with current consensus about hydration 1,600 mL/day (female and 2,000 mL/day (male. Results: The average fluid intake slightly surpassed the recommended: mean of 2,049 mL/day (2,223 mL in males, 1,938 mL in females. Portugal stood out due to its lower intake (mean of 1,365 mL/day. Water contributed the largest part to total fluid intake (37% in all countries (mean of 1,365 mL/day. Hot beverages (18% and milk and derivates (17% follow water in highest consumption. The 20% of males and only 0.3% of females knew recommendations of hydration, while 63.3% of males and 62% of females followed them. Only 8.4% of people who follow the recommendations know them. Conclusion: The people studied surpassed the recommendation, although the majority did not realize. Future research should examine actual beverage consumption patterns and evaluate if the current consensuses are correctly adapted to the population needs. Hydration's policies should be transmitted to the population for their knowledge and adequate compliance.

  17. SOURCES OF DIFFERENCES IN CALCULATIONS AND EXPERIMENTAL TEST RESULTS OF FATIGUE LIFE OF STRUCTURAL ELEMENTS

    Directory of Open Access Journals (Sweden)

    Józef SZALA

    2014-06-01

    Full Text Available Calculation results are the base for evaluation of fatigue life of structural elements during machine design processes. It results from the fact that there are no material objects in the phase of existence of a product. Reliability of tests results is an essential element in the calculation fatigue life evaluation method and it can be evaluated by comparison of the results with experimental ones. In the paper there was performed an analysis of the chosen factors essentially influencing conformity of calculation results and experimental test ones connected with basic elements of a calculation algorithm including: - elaboration and analysis of service loadings of a structural element, - determination and analysis of cyclic properties of structural elements, - selection of fatigue damage accumulation hypothesis being a description of fatigue life processes. The mentioned analysis was illustrated with examples of fatigue life tests performed in the Machine Design Department of the University of Technology and Agriculture within the research grant no. 2221/B/T02/2010/39 financed by The Ministry of Science and Higher Education and National Science Centre.

  18. The Current State of Knowledge of Hepatic Ischemia-Reperfusion Injury Based on Its Study in Experimental Models

    Science.gov (United States)

    Mendes-Braz, M.; Elias-Miró, M.; Jiménez-Castro, M. B.; Casillas-Ramírez, A.; Ramalho, F. S.; Peralta, C.

    2012-01-01

    The present review focuses on the numerous experimental models used to study the complexity of hepatic ischemia/reperfusion (I/R) injury. Although experimental models of hepatic I/R injury represent a compromise between the clinical reality and experimental simplification, the clinical transfer of experimental results is problematic because of anatomical and physiological differences and the inevitable simplification of experimental work. In this review, the strengths and limitations of the various models of hepatic I/R are discussed. Several strategies to protect the liver from I/R injury have been developed in animal models and, some of these, might find their way into clinical practice. We also attempt to highlight the fact that the mechanisms responsible for hepatic I/R injury depend on the experimental model used, and therefore the therapeutic strategies also differ according to the model used. Thus, the choice of model must therefore be adapted to the clinical question being answered. PMID:22649277

  19. Technological insights: Combined impedance manometry for esophageal motility testing-current results and further implications

    Institute of Scientific and Technical Information of China (English)

    Huan Nam Nguyen; Gerson Ricardo Souza Domingues; Frank Lammert

    2006-01-01

    This review focuses on current aspects of the novel technology of combined impedance manometry for esophageal motility testing. It presents methodological features, summarizes current results and discusses implications for further research. The combined technique assesses simultaneously bolus transport and associated peristalsis, thus allowing detailed analysis of the relationships between bolus transit and esophageal motility. Recent studies demonstrate that combined impedance manometry provides important additional information about esophageal motility as compared to conventional manometry: (1) monitoring of bolus transport patterns, (2) calculation of bolus transit parameters, (3) evaluation of bolus clearance,(4) monitoring of swallow associated events such as air movement and reflux, and (5) investigation of the relationships between bolus transit and LES relaxation.Studies with healthy subjects have identified several useful parameters for comprehensive assessment of eosphageal function. These parameters were found to be pathological in patients with classical achalasia,mild GERD, and ineffective esophageal motility. The technology of combined impedance manometry provides an important new tool for esophageal function testing,advancing both clinical and basic research. However,several important issues remain to be standardized to make the technique suitable for widely clinical use.

  20. Experimental evaluation of IGBT junction temperature measurement via peak gate current

    DEFF Research Database (Denmark)

    Baker, Nick; Munk-Nielsen, Stig; Iannuzzo, Francesco

    2015-01-01

    Temperature sensitive electrical parameters allow junction temperature measurements on power semiconductors without modification to module packaging. The peak gate current has recently been proposed for IGBT junction temperature measurement and relies on the temperature dependent resistance of th...

  1. Currents, HF Radio-derived, Monterey Bay, 25 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  2. Currents, HF Radio-derived, Ano Nuevo, Normal Model, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal...

  3. Currents, HF Radio-derived, SF Bay Outlet, 25 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  4. Currents, HF Radio-derived, SF Bay, 33 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 33 hour running average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  5. Currents, HF Radio-derived, Bodega Bay, 25 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  6. Currents, HF Radio-derived, Ano Nuevo, 25 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  7. Currents, HF Radio-derived, Ano Nuevo, Normal Model, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal model....

  8. Currents, HF Radio-derived, Ano Nuevo, 25 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  9. Currents, HF Radio-derived, SF Bay Outlet, Normal Model, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal model....

  10. Experimental pain processing in individuals with cognitive impairment: current state of the science

    DEFF Research Database (Denmark)

    Defrin, R; Amanzio, Martina; de Tomasso, M

    2015-01-01

    to cognitively unimpaired individuals. Our current understanding of the neurobiological mechanisms underpinning these alterations is limited, but may be enhanced through the use of animal models of CI which also exhibit alterations in nociceptive responding. Further research employing additional behavioural...

  11. Currents, HF Radio-derived, Monterey Bay, Normal Model, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal model....

  12. Currents, HF Radio-derived, Monterey Bay, Normal Model, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal...

  13. Currents, HF Radio-derived, SF Bay Outlet, 25 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  14. Currents, HF Radio-derived, Bodega Bay, 25 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  15. Currents, HF Radio-derived, Monterey Bay, 25 hr, Zonal, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 25 hour running average of the zonal component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  16. Currents, HF Radio-derived, SF Bay Outlet, Normal Model, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal...

  17. Single-Case Experimental Designs: A Systematic Review of Published Research and Current Standards

    Science.gov (United States)

    Smith, Justin D.

    2012-01-01

    This article systematically reviews the research design and methodological characteristics of single-case experimental design (SCED) research published in peer-reviewed journals between 2000 and 2010. SCEDs provide researchers with a flexible and viable alternative to group designs with large sample sizes. However, methodological challenges have…

  18. Current and future experimental strategies for structural analysis of trichothecene mycotoxins--a prospectus.

    Science.gov (United States)

    Shank, Roxanne A; Foroud, Nora A; Hazendonk, Paul; Eudes, François; Blackwell, Barbara A

    2011-12-01

    Fungal toxins, such as those produced by members of the order Hypocreales, have widespread effects on cereal crops, resulting in yield losses and the potential for severe disease and mortality in humans and livestock. Among the most toxic are the trichothecenes. Trichothecenes have various detrimental effects on eukaryotic cells including an interference with protein production and the disruption of nucleic acid synthesis. However, these toxins can have a wide range of toxicity depending on the system. Major differences in the phytotoxicity and cytotoxicity of these mycotoxins are observed for individual members of the class, and variations in toxicity are observed among different species for each individual compound. Furthermore, while diverse toxicological effects are observed throughout the whole cellular system upon trichothecene exposure, the mechanism of toxicity is not well understood. In order to comprehend how these toxins interact with the cell, we must first have an advanced understanding of their structure and dynamics. The structural analysis of trichothecenes was a subject of major interest in the 1980s, and primarily focused on crystallographic and solution-state Nuclear Magnetic Resonance (NMR) spectroscopic studies. Recent advances in structural determination through solution- and solid-state NMR, as well as computation based molecular modeling is leading to a resurgent interest in the structure of these and other mycotoxins, with the focus shifting in the direction of structural dynamics. The purpose of this work is to first provide a brief overview of the structural data available on trichothecenes and a characterization of the methods commonly employed to obtain such information. A summary of the current understanding of the relationship between structure and known function of these compounds is also presented. Finally, a prospectus on the application of new emerging structural methods on these and other related systems is discussed.

  19. Current and Future Experimental Strategies for Structural Analysis of Trichothecene Mycotoxins—A Prospectus

    Directory of Open Access Journals (Sweden)

    Barbara A. Blackwell

    2011-12-01

    Full Text Available Fungal toxins, such as those produced by members of the order Hypocreales, have widespread effects on cereal crops, resulting in yield losses and the potential for severe disease and mortality in humans and livestock. Among the most toxic are the trichothecenes. Trichothecenes have various detrimental effects on eukaryotic cells including an interference with protein production and the disruption of nucleic acid synthesis. However, these toxins can have a wide range of toxicity depending on the system. Major differences in the phytotoxicity and cytotoxicity of these mycotoxins are observed for individual members of the class, and variations in toxicity are observed among different species for each individual compound. Furthermore, while diverse toxicological effects are observed throughout the whole cellular system upon trichothecene exposure, the mechanism of toxicity is not well understood. In order to comprehend how these toxins interact with the cell, we must first have an advanced understanding of their structure and dynamics. The structural analysis of trichothecenes was a subject of major interest in the 1980s, and primarily focused on crystallographic and solution-state Nuclear Magnetic Resonance (NMR spectroscopic studies. Recent advances in structural determination through solution- and solid-state NMR, as well as computation based molecular modeling is leading to a resurgent interest in the structure of these and other mycotoxins, with the focus shifting in the direction of structural dynamics. The purpose of this work is to first provide a brief overview of the structural data available on trichothecenes and a characterization of the methods commonly employed to obtain such information. A summary of the current understanding of the relationship between structure and known function of these compounds is also presented. Finally, a prospectus on the application of new emerging structural methods on these and other related systems is

  20. Solubility of water in fluorocarbons: Experimental and COSMO-RS prediction results

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Mara G.; Carvalho, Pedro J. [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Santos, Luis M.N.B.F. [CIQ, Departamento de Quimica, Faculdade de Ciencias da Universidade do Porto, R. Campo Alegre 687, 4169-007 Porto (Portugal); Gomes, Ligia R. [REQUIMTE, Departamento de Quimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, P-4169-007 Porto (Portugal); Marrucho, Isabel M. [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Coutinho, Joao A.P., E-mail: jcoutinho@ua.p [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal)

    2010-02-15

    This work aims at providing experimental and theoretical information about the water-perfluorocarbon molecular interactions. For that purpose, experimental solubility results for water in cyclic and aromatic perfluorocarbons (PFCs), over the temperature range between (288.15 and 318.15) K, and at atmospheric pressure, were obtained and are presented. From the experimental solubility dependence on temperature, the partial molar solution and solvation thermodynamic functions such as Gibbs free energy, enthalpy and entropy were determined and are discussed. The process of dissolution of water in PFCs is shown to be spontaneous for cyclic and aromatic compounds. It is demonstrated that the interactions between the non-aromatic PFCs and water are negligible while those between aromatic PFCs and water are favourable. The COSMO-RS predictive capability was explored for the description of the water solubility in PFCs and others substituted fluorocompounds. The COSMO-RS is shown to be a useful model to provide reasonable predictions of the solubility values, as well as to describe their temperature and structural modifications dependence. Moreover, the molar Gibbs free energy and molar enthalpy of solution of water are predicted remarkably well by COSMO-RS while the main deviations appear for the prediction of the molar entropy of solution.

  1. Recovery of yttrium from cathode ray tubes and lamps' fluorescent powders: experimental results and economic simulation.

    Science.gov (United States)

    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.

  2. Modeled and experimental results of an omnidirectional free-space optical receiver architecture

    Science.gov (United States)

    Murshid, Syed H.; Lovell, Gregory L.; Finch, Michael F.

    2017-03-01

    Free-space optical (FSO) communications provide point-to-point connectivity while offering many advantages in size, weight, and power as compared to radio frequency. It has the potential to provide fiber-optic data rates without the need for lengthy fiber cables. Omnidirectional FSO, also known as O-FSO systems, provide a non-line-of-sight option for data communications. They are gaining popularity in short-distance networks. Most existing O-FSO links range from 1 to 100 m and present experimental/simulated data rates ranging between 5 kb/s and 1 Mb/s. A 2.5-Gb/s O-FSO system was recently reported with a range of 25 cm. This paper employs a fiber bundle as an O-FSO receiver. The energy collected by the receiver is related to the acceptance cone of each fiber. The fiber bundle integrates the optical power gathered by the individual fibers and couples it to the photodetector. Experimental data rates approaching 100 kb/s over a meter long system are presented, whereas simulated results support a data rate up to 52 Mb/s for distances approaching a kilometer. Theoretical and experimental optical power versus range is also presented for the proposed O-FSO architecture, using on-off keying.

  3. Investigating dynamic parameters in HWZPR ased on the experimental and calculated results

    Energy Technology Data Exchange (ETDEWEB)

    Nasrazadani, Zahra; Behfamia, Manochehar; Khosandi, Jamshid; Mirvakili, Mohammad [Reactors Research School, Nuclear Science And Technology Research Institute, Atomic Energy Organization of Iran, Esfahan (Iran, Islamic Republic of)

    2016-10-15

    The neutron decay constant, α, and effective delayed neutron fraction, β{sub eff}, are important parameters for the control of the dynamic behavior of nuclear reactors. For the heavy water zero power reactor (HWZPR), this document describes the measurements of the neutron decay constant by noise analysis methods, including variance to mean (VTM) ratio and endogenous pulse source (EPS) methods. The measured α is successively used to determine the experimental value of the effective delayed neutron fraction as well. According to the experimental results, β{sub eff} of the HWZPR reactor under study is equal to 7.84e-3. This value is finally used to validate the calculation of the effective delayed neutron fraction by the Monte Carlo methods that are discussed in the document. Using the Monte Carlo N-Particle (MCNP)-4C code, a β{sub eff} value of 7.58e-3 was obtained for the reactor under study. Thus, the relative difference between the β{sub eff} values determined experimentally and by Monte Carlo methods was estimated to be < 4%.

  4. Current IGEX Results for Neutrinoless Double-Beta Decay of {sup 76}Ge

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, D.; Aalseth, C.E.; Avignone, F.T.; Brodzinski, R.L.; Cebrian, S.; Garcia, E.; Hensley, W.K.; Irastorza, I.G.; Kirpichnikov, I.V.; Klimenko, A.A.; Miley, H.S.; Morales, A.; Morales, J.; Ortiz de Solorzano, A.; Osetrov, S.B.; Pogosov, V.S.; Puimedon, J.; Reeves, J.H.; Sarsa, M.L.; Scopel, S.; Smolnikov, A.A.; Tamanyan, A.G.; Vasenko, A.A.; Vasiliev, S.I.; Villar, J.A

    2000-06-01

    The International Germanium Experiment (IGEX) is currently operating three 2-kg enriched germanium detectors in the Canfranc Underground Laboratory (Spain) at 2450 mwe, in a search for the neutrinoless double-beta decay of {sup 76}Ge. The detectors are equipped with Pulse Shape Analysis electronics. This implementation of Pulse Shape Discrimination results in a rejection of 60%-80% of the background in the 2.0-2.5 MeV energy interval. Analysis of 116.75 mole-years of data yields a lower bound {>=} 1.57 x 10{sup 25}y (or T{sup 0{nu}}{sub 1/2} {>=} 1.13 x 10{sup 25}y without PSD) (90% C.L.) corresponding to (m{sub {nu}}) < (0.33 - 1.31) eV, depending on the theoretical nuclear matrix elements used to extract the neutrino mass parameter.

  5. Current IGEX Results for Neutrinoless Double-Beta Decay of 76Ge

    Science.gov (United States)

    González, D.; Aalseth, C. E.; Avignone, F. T., Jr.; Brodzinski, R. L.; Cebrián, S.; García, E.; Hensley, W. K.; Irastorza, I. G.; Kirpichnikov, I. V.; Klimenko, A. A.; Miley, H. S.; Morales, A.; Morales, J.; Ortiz de Solórzano, A.; Osetrov, S. B.; Pogosov, V. S.; Puimedón, J.; Reeves, J. H.; Sarsa, M. L.; Scopel, S.; Smolnikov, A. A.; Tamanyan, A. G.; Vasenko, A. A.; Vasiliev, S. I.; Villar, J. A.

    2000-06-01

    The International Germanium Experiment (IGEX) is currently operating three 2-kg enriched germanium detectors in the Canfranc Underground Laboratory (Spain) at 2450 mwe, in a search for the neutrinoless double- beta decay of 76Ge. The detectors are equipped with Pulse Shape Analysis electronics. This implementation of Pulse Shape Discrimination results in a rejection of 60%-80% of the background in the 2.0-2.5 MeV energy interval. Analysis of 116.75 mole-years of data yields a lower bound ≥ 1.57 × 10 25y ( or T {1}/{2}0ν ≥ 1.13 × 10 25y without PSD) (90% C.L.) corresponding to < (0.33 - 1.31) eV, depending on the theoretical nuclear matrix elements used to extract the neutrino mass parameter.

  6. Parathyroid scintigraphy protocols in Finland in 2010. Results of the query and current status

    Energy Technology Data Exchange (ETDEWEB)

    Tunninen, V. [The Dept. of Nuclear Medicine, Satakunta Central Hospital, Pori (Finland); Kauppinen, T. [HUS Helsinki Medical Imaging Centre, Helsinki Univ. Hospital (Finland); Eskola, H. [The Dept. of Biomedical Engineering, Tampere Univ. of Technology (Finland); Koskinen, M.O. [Medical Imaging Centre, Tampere Univ. Hospital (Finland)

    2010-07-01

    The goal of this study was to describe current clinical parathyroid scintigraphy (PS) protocols in Finland. Methods: All departments of nuclear medicine in Finland were contacted, and instructions regarding PS were requested. Results: Instructions regarding PS were received from all of the departments that perform PS (n = 19). Seven hundred and sixty-nine PS studies were performed in 2009 (between 7 and 209 per hospital). Three methods of PS were used. The dual-phase method with {sup 99m}Tc-sestamibi is used in seven hospitals, the dual-tracer method with {sup 123}I/{sup 99m}Tc-sestamibi in eleven, and {sup 99m}TcO{sub 4}/{sup 99m}Tc-sestamibi in one hospital. The activities of {sup 99m}Tc-sestamibi, {sup 123}I and {sup 99m}TcO{sub 4} were 150-800 MBq, 10-30 MBq and 50 MBq, respectively. The anterior image with parallel-hole collimators, the anterior image with pinhole collimator, the oblique angles with pinhole collimator, SPECT and hybrid CT with SPECT were acquired in 84%, 26%, 16%, 63%, and 42% of the hospitals, respectively. Because the imaging techniques were combined, one to four acquisitions were performed per patient. Scatter and attenuation correction were used in five protocols. A correction for crosstalk of {sup 123}I and {sup 99m}Tc gamma energies was not used, but the amount of crosstalk was decreased by using narrow or asymmetric energy windows in all dual isotope protocols. Conclusion: 19 hospitals used 18 different study protocols. Thus, significant variability exists in the current practice of PS in Finland. The protocols should be tested with known phantoms to determine any differences in sensitivities for detecting small active structures. Further studies with phantoms are needed to determine the optimal imaging techniques. The results of these phantom studies will provide guidelines for proposing national recommendations for PS. (orig.)

  7. Comparison of experimental data with results of some drying models for regularly shaped products

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, Ahmet [Aksaray University, Department of Mechanical Engineering, Aksaray (Turkey); Aydin, Orhan [Karadeniz Technical University, Department of Mechanical Engineering, Trabzon (Turkey); Dincer, Ibrahim [University of Ontario Institute of Technology, Faculty of Engineering and Applied Science, Oshawa, ON (Canada)

    2010-05-15

    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 {phi}=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 x 10{sup -5} and 5.981 x 10{sup -5} m{sup 2}/h for slab products, 0.818 x 10{sup -5} and 6.287 x 10{sup -5} m{sup 2}/h for cylindrical products and 1.213 x 10{sup -7} and 7.589 x 10{sup -7} m{sup 2}/h spherical products using the model-I and 0.316 x 10{sup -5}-5.072 x 10{sup -5} m{sup 2}/h for slab products, 0.580 x 10{sup -5}-9.587 x 10{sup -5} m{sup 2}/h for cylindrical products and 1.408 x 10{sup -7}-13.913 x 10{sup -7} m{sup 2}/h spherical products using the model-II. (orig.)

  8. Wind refrigeration : design and results of an experimental facility; Refrigeracion eolica: Diseno y resultados de una instalacion experimental

    Energy Technology Data Exchange (ETDEWEB)

    Beltran, R. G.; Talero, A.

    2004-07-01

    This article describes the experimental setup used to obtain design parameters for a wind driven refrigeration equipment. The system compressor is directly coupled to the wind mill and will provide refrigeration to a community located in La Guajira in northern Colombia. The testing on the experimental installation assessed the refrigeration capacity that could be provided by an open type commercial compressor coupled to the wind mill axis. Power and torque requirements have been evaluated for different wind mill rotational speeds. An assessment of the local conditions relating to wind speed, frequency and preferred direction for the installation site has been made based on measurements by the Meteorological National Institute and independent data from other sources. (Author)

  9. Parametric correlations between experimental results and the base isolation, in situ, structural ones

    Directory of Open Access Journals (Sweden)

    Polidor Bratu

    2014-03-01

    Full Text Available The paper addresses the topic of the inconsistency between experimental, laboratory results for antiseismic devices and the dynamic stiffness, internal damping and dissipation parameters through additional devices. The necessary corrections of the stiffness and dissipation (damping parameters will be presented when the antiseismic devices are equipped to satisfy the adequate functions in a complex structural system (buildings, viaducts, bridges under the conditions of seismic motions characteristic to the Romanian territory. In this context, the kinematic excitation method, compared to the dynamic evaluation method of the vibration dissipation capacity, produced by a seismic shock is shown.

  10. Development of X-ray microcalorimeters based on SOI technology and experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Szeflinski, V. [CEA, Irfu, Service d' Astrophysique, F-91191 Gif-sur-Yvette (France)], E-mail: virginie.szeflinski@cea.fr; Aliane, A.; De Moro, F. [CEA, Irfu, LETI-MINATEC, F-38053 Grenoble (France); Pigot, C.; Sauvageot, J-L. [CEA, Irfu, Service d' Astrophysique, F-91191 Gif-sur-Yvette (France); Agnese, P.; Gasse, A.; Ribot, H. [CEA, Irfu, LETI-MINATEC, F-38053 Grenoble (France); Gremion, E.; De La Broise, X.; Navick, X.F. [CEA, Irfu, Service d' electronique, detecteur et informatique, F-91191 Gif-sur-Yvette (France)

    2009-10-21

    We are developing an X-ray spectro-imaging detector at cryogenic temperature (<100 mK) for next space generation missions, using silicon technology. Each pixel of this array detector is made of a tantalum absorber bonded by indium bump hybridization, to an implanted and high-temperature diffused silicon thermistor. The thermo-mechanical link, provided by the indium bump hybridization, is being improved in terms of thermal capacitance. We present the state of development and experimental results on this new generation of X-ray microcalorimeters.

  11. Preliminary Results on the Experimental Investigation of the Structure Functions of Bound Nucleons

    Energy Technology Data Exchange (ETDEWEB)

    Bodek, Arie [Univ. of Rochester, NY (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    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, $R_A< R_D$.

  12. Cacao roasting in rural areas of Peru using concentrated solar thermal energy: experimental results

    Directory of Open Access Journals (Sweden)

    Veynandt François

    2016-01-01

    Full Text Available Solar food processing is gaining interest for income generation. Our solar cacao roaster, designed for rural areas, consists in a horizontal rotating drum, opened at one end to collect solar radiation from Scheffler concentrators of 2.7 or 8 m2. The experimental results presented bring knowledge on the system's behavior and optimal operation. The influence of the most significant parameters is studied: quantity of cacao, absorptivity of drum's coating, thermal insulation, inclination and rotational speed of the drum. Cacao temperature and direct solar irradiance are monitored to evaluate the performance in roasting time per kilogram of cacao.

  13. An experimental result of surface roughness machining performance in deep hole drilling

    Directory of Open Access Journals (Sweden)

    Mohamad Azizah

    2016-01-01

    Full Text Available This study presents an experimental result of a deep hole drilling process for Steel material at different machining parameters which are feed rate (f, spindle speed (s, the depth of the hole (d and MQL, number of drops (m on surface roughness, Ra. The experiment was designed using two level full factorial design of experiment (DoE with centre points to collect surface roughness, Ra values. The signal to noise (S/N ratio analysis was used to discover the optimum level for each machining parameters in the experiment.

  14. Preliminary Results on the Experimental Investigation of the Structure Functions of Bound Nucleons

    CERN Document Server

    Bodek, A

    2015-01-01

    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, $R_A< R_D$.

  15. Experimental results for optimal placement of piezoelectric plates for active vibration control of a cantilever beam

    Directory of Open Access Journals (Sweden)

    F. Botta

    2013-10-01

    Full Text Available The fatigue phenomena correlated to the gas turbine blades vibrations can lead to catastrophic failure. To damp the vibrations amplitude typically damping passive systems are used. In the last years the interest in the piezoelectric materials, and their use as damping elements, has received considerable attention by many researchers. Recently different research groups have started to study their use in blades of turbomachinery. Because of their effectiveness strongly depends on their position, some of the authors have proposed ([15], [17] a new model to find the optimal position to control the multimode vibrations. Such model has been corroborated by experimental results for different combinations of excited eigenmodes ([16], [18

  16. First X-ray fluorescence CT experimental results at the SSRF X-ray imaging beamline

    Institute of Scientific and Technical Information of China (English)

    DENG Biao; YANG Qun; XIE Hong-Lan; DU Guo-Hao; XIAO Wi-Qiao

    2011-01-01

    X-ray fluorescence CT is a non-destructive technique for detecting elemental composition and distribution inside a specimen. In this paper, the first experimental results of X-ray fluorescence CT obtained at the SSRF X-ray imaging beamline (BL13W1) are described. The test samples were investigated and the 2D elemental image was reconstructed using a filtered back-projection algorithm. In the sample the element Cd was observed. Up to now, the X-ray fluorescence CT could be carried out at the SSRF X-ray imaging beamline.

  17. Cacao roasting in rural areas of Peru using concentrated solar thermal energy: experimental results

    Directory of Open Access Journals (Sweden)

    Veynandt François

    2016-01-01

    Full Text Available Solar food processing is gaining interest for income generation. Our solar cacao roaster, designed for rural areas, consists in a horizontal rotating drum, opened at one end to collect solar radiation from Scheffler concentrators of 2.7 or 8 m2. The experimental results presented bring knowledge on the system's behavior and optimal operation. The influence of the most significant parameters is studied: quantity of cacao, absorptivity of drum's coating, thermal insulation, inclination and rotational speed of the drum. Cacao temperature and direct solar irradiance are monitored to evaluate the performance in roasting time per kilogram of cacao.

  18. Active vibration absorber for the CSI evolutionary model - Design and experimental results. [Controls Structures Interaction

    Science.gov (United States)

    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.

  19. EFFICENCY OF PHOTOACTIVATED DISINFECTION ON EXPERIMENTAL BIOFILM - SCANING ELECTRON MICROSCOPY RESULTS

    Directory of Open Access Journals (Sweden)

    Ivan Filipov

    2013-10-01

    Full Text Available Photoactivated disinfection is a new antimicrobial method for root canal disinfection, based on photodynamic therapy.Purpose: The goal of this study is to investigate the antimicrobial effect of photoactivated disinfection on experimental biofilm from Enterococcus faecalis and Candida albicans, through scanning electron microscopy.Material and Methods: Freshly extracted, one root teeth were prepared with a sequence of rotary nickel-titanium files (ProTaper ; Dentsply ; Mailefer , irrigated, the external root canal surfaces isolated with nail polish and autoclaved. After the incubation with the experimental biofilm, the root canals were filled with photosensitizer - Toluidine Blue – 0,01% and irradiated with Foto San(CMS Dental, 630 nm, 2000mW/cm2 for 30 seconds.SEM was performed on the coronal, middle and apical third of the root canal, for evaluation of the results.Results and discussion: In the range of 600 to 8000, SEM showed significant reduction of microorganisms from the canal system. A large increase in microorganisms was observed, showing a disturbance in the cell membrane, as effect from the activation of chromophore with the laser and the penetration of the photosensitizer in dental tubules. In the apical third single microorganisms were observed. This may due to decreased penetration of the photosensitizer, incomplete pervasion of MB in the biofilm or insufficient oxygenation.Conclusion: FAD has the potential to be a good alternative and addition to the conventional root canal disinfection methods.SEM is a precise method for endodontic treatment result evaluation.

  20. Investigation of sonar transponders for offshore wind farms: modeling approach, experimental setup, and results.

    Science.gov (United States)

    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.

  1. Femtosecond laser for glaucoma treatment: the comparison between simulation and experimentation results on ocular tissue removal

    Science.gov (United States)

    Hou, Dong Xia; Ngoi, Bryan K. A.; Hoh, Sek Tien; Koh, Lee Huat K.; Deng, Yuan Zi

    2005-04-01

    In ophthalmology, the use of femtosecond lasers is receiving more attention than ever due to its extremely high intensity and ultra short pulse duration. It opens the highly beneficial possibilities for minimized side effects during surgery process, and one of the specific areas is laser surgery in glaucoma treatment. However, the sophisticated femtosecond laser-ocular tissue interaction mechanism hampers the clinical application of femtosecond laser to treat glaucoma. The potential contribution in this work lies in the fact, that this is the first time a modified moving breakdown theory is applied, which is appropriate for femtosecond time scale, to analyze femtosecond laser-ocular tissue interaction mechanism. Based on this theory, energy deposition and corresponding thermal increase are studied by both simulation and experimentation. A simulation model was developed using Matlab software, and the simulation result was validated through in-vitro laser-tissue interaction experiment using pig iris. By comparing the theoretical and experimental results, it is shown that femtosecond laser can obtain determined ocular tissue removal, and the thermal damage is evidently reduced. This result provides a promising potential for femtosecond laser in glaucoma treatment.

  2. Single-Case Experimental Design: Current Standards and Applications in Occupational Therapy.

    Science.gov (United States)

    Lane, Justin D; Ledford, Jennifer R; Gast, David L

    Occupational therapy is a field with a long-standing history of recommending and implementing interventions designed to improve the quality of life of clients with disabilities. Often, the interventions are individualized to meet the needs of this diverse group of clients in dynamic settings. Identifying effective and efficient interventions for such a diverse group of clients and settings requires a flexible research approach. Single-case experimental designs (SCEDs) allow practitioners and researchers to answer experimental questions within the context of rigorous research designs. The purpose of this article is to highlight the similarities between the mission of occupational therapy and SCEDs. Recommendations for designing single-case studies with the framework provided by the Single-Case Reporting Guideline in Behavioral Interventions are provided. In addition, common problems and proposed solutions, along with implications for practitioners and researchers, are provided. Copyright © 2017 by the American Occupational Therapy Association, Inc.

  3. The case for a directional dark matter detector and the status of current experimental efforts

    CERN Document Server

    Ahlen, S; Battat, J B R; Billard, J; Bozorgnia, N; Burgos, S; Caldwell, T; Carmona, J M; Cebrián, S; Colas, P; Dafni, T; Daw, E; Dujmic, D; Dushkin, A; Fedus, W; Ferrer, E; Finkbeiner, D; Fisher, P H; Forbes, J; Fusayasu, T; Galan, J; Gamble, T; Ghag, C; Giomataris, Yu; Gold, M; Gomez, H; Gómez, M E; Gondolo, P; Green, A; Grignon, C; Guillaudin, O; Hagemann, C; Hattori, K; Henderson, S; Higashi, N; Ida, C; Iguaz, F J; Inglis, A; Irastorza, I G; Iwaki, S; Kaboth, A; Kabuki, S; Kadyk, J; Kallivayalil, N; Kubo, H; Kurosawa, S; Kudryavtsev, V A; Lamy, T; Lanza, R; Lawson, T B; Lee, A; Lee, E R; Lin, T; Loomba, D; López, J; Luzón, G; Manobu, T; Martoff, J; Mayet, F; McCluskey, B; Miller, E; Miuchi, K; Monroe, J; Morgan, B; Muna, D; Murphy, A St J; Naka, T; Nakamura, K; Nakamura, M; Nakano, T; Nicklin, G G; Nishimura, H; Niwa, K; Paling, S M; Parker, J; Petkov, A; Pipe, M; Pushkin, K; Robinson, M; Rodríguez, A; Rodríguez-Quintero, J; Sahin, T; Sanderson, R; Sanghi, N; Santos, D; Sato, O; Sawano, T; Sciolla, G; Sekiya, H; Slatyer, T R; Snowden-Ifft, D P; Spooner, N J C; Sugiyama, A; Takada, A; Takahashi, M; Takeda, A; Tanimori, T; Taniue, K; Tomas, A; Tomita, H; Tsuchiya, K; Turk, J; Tziaferi, E; Ueno, K; Vahsen, S; Vanderspek, R; Vergados, J; Villar, J A; Wellenstein, H; Wolfe, I; Yamamoto, R K; Yegoryan, H

    2010-01-01

    We present the case for a dark matter detector with directional sensitivity. This document was developed at the 2009 CYGNUS workshop on directional dark matter detection, and contains contributions from theorists and experimental groups in the field. We describe the need for a dark matter detector with directional sensitivity; each directional dark matter experiment presents their project's status; and we close with a feasibility study for scaling up to a one ton directional detector, which would cost around $150M.

  4. Experimental Test of Alternating-Current Zeeman Interference Effect in Ramsey Separated Oscillating Fields

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jun-Hai; WANG Feng-Zhi; YANG Dong-Hai

    2004-01-01

    An experimental test of ac Zeeman effect in an optically pumped caesium beam frequency standard is reported and analysed. An interference pattern of the atomic energy level shift as a function of the applied microwave field near the atomic transition frequency was observed. It was superimposed on the dispersion lineshape of a normal ac Zeeman effect. This effect was analysed with the atomic wavefunction phase analysing method.

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

    Directory of Open Access Journals (Sweden)

    Matthew W Peterson

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  7. Height of burst explosions: a comparative study of numerical and experimental results

    Science.gov (United States)

    Omang, M.; Christensen, S. O.; Børve, S.; Trulsen, J.

    2009-06-01

    In the current work, we use the Constant Volume model and the numerical method, Regularized Smoothed Particle Hydrodynamics (RSPH) to study propagation and reflection of blast waves from detonations of the high explosives C-4 and TNT. The results from simulations of free-field TNT explosions are compared to previously published data, and good agreement is found. Measurements from height of burst tests performed by the Norwegian Defence Estates Agency are used to compare against numerical simulations. The results for shock time of arrival and the pressure levels are well represented by the numerical results. The results are also found to be in good agreement with results from a commercially available code. The effect of allowing different ratios of specific heat capacities in the explosive products are studied. We also evaluate the effect of changing the charge shape and height of burst on the triple point trajectory.

  8. Hip resurfacing arthroplasty: mid-term results in 486 cases and current indication in our institution.

    Science.gov (United States)

    Ribas, Manuel; Cardenas, Carlomagno; Astarita, Emanuele; Moya, Esther; Bellotti, Vittorio

    2014-10-02

    In the previous decade, metal-on-metal hip resurfacing has been considered an attractive option and theoretically advantageous over conventional total hip arthroplasty, especially in young active patients. Different authors have reported favourable mid-term clinical and functional results with acceptable survival rates. Proper indication and planning, as accurate technical execution have been advocated to be crucial elements for success.Concerns regarding serum metal ion levels and possible clinical implications have led in the last years to a decline in the use of metal-on-metal hip resurfacing and metal-on-metal bearings in general.The aim of this study is to present the results of our first 486 cases of hybrid hip resurfacing arthroplasties with a second generation cementing technique, and to describe our current restricted indication of this type of prosthesis, in the light of recent findings in the literature about the possible complications related to metallosis or improper patient selection. Global survivorship of our series was 97.9% at a mean follow-up of 7.2 years.In the second season of our experience the indication is restrictive. The candidate for a resurfacing hip replacement is a young and active male patient, with good bone quality, that has been made aware of the risks and benefits of this type of prosthesis.

  9. Resonance Chiral Lagrangian Currents and Experimental Data for $\\tau^-\\to\\pi^{-}\\pi^{-}\\pi^{+}\

    CERN Document Server

    Nugent, I M; Roig, P; Shekhovtsova, O; Was, Z

    2013-01-01

    In this paper we document the modifications introduced to the previous version of the Resonance Chiral Lagrangian current ({\\it Phys.Rev.} {\\bf D86} (2012) 113008) of the $\\tau^\\pm \\to \\pi^\\pm \\pi^\\pm \\pi^\\mp \

  10. Experimental Study on the Influence of AC Stray Current on the Cathodic Protection of Buried Pipe

    Directory of Open Access Journals (Sweden)

    Qingmiao Ding

    2016-01-01

    Full Text Available The size of the damaged area of the coating and its position on the pipeline impacted the cathodic protection potential, and there was a damaged area of the greatest impact value. When damaged area was 300 mm2, the IR drop was the largest, and this situation could easily lead to inadequate protection; when the parallel spacing between pipeline and interference source was unchanged, the measured value curves of cathodic protection potential presented “U” shaped trend with the increasing stray current interference intensity. Under certain parallel spacing between pipeline and interference source, high alternating stray current intensity would cause serious negative offsets, so that the overprotection of the pipeline occurred, and make the coating crack; there was a parallel threshold length. When less than the threshold, the pipe-ground potential increases rapidly with the parallel length increasing. In order to judge whether a pipeline was interference by AC stray current and the risk of stray current corrosion, we should make a comprehensive analysis of the cathodic protection energizing potential, the switch-off potential, AC pipe-soil potential, IR drops, and so on.

  11. Simulation and experimental results of optical and thermal modeling of gold nanoshells

    Energy Technology Data Exchange (ETDEWEB)

    Ghazanfari, Lida; Khosroshahi, Mohammad E., E-mail: khosrom@mie.utoronto.ca

    2014-09-01

    This paper proposes a generalized method for optical and thermal modeling of synthesized magneto-optical nanoshells (MNSs) for biomedical applications. Superparamagnetic magnetite nanoparticles with diameter of 9.5 ± 1.4 nm are fabricated using co-precipitation method and subsequently covered by a thin layer of gold to obtain 15.8 ± 3.5 nm MNSs. In this paper, simulations and detailed analysis are carried out for different nanoshell geometry to achieve a maximum heat power. Structural, magnetic and optical properties of MNSs are assessed using vibrating sample magnetometer (VSM), X-ray diffraction (XRD), UV–VIS spectrophotometer, dynamic light scattering (DLS), and transmission electron microscope (TEM). Magnetic saturation of synthesized magnetite nanoparticles are reduced from 46.94 to 11.98 emu/g after coating with gold. The performance of the proposed optical–thermal modeling technique is verified by simulation and experimental results. - Highlights: • Proposing a generalized method for optical and thermal modeling of nanoshells • Verification of the proposed modeling technique by simulation and experimental results • Simulations for different nanoshell geometry to achieve a maximum heat power • Synthesis and characterization of magneto-optical nanoshells.

  12. Fuel-rich, catalytic reaction experimental results. [fuel development for high-speed civil transport aircraft

    Science.gov (United States)

    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.

  13. Epistemology and expectations survey about experimental physics: Development and initial results

    Science.gov (United States)

    Zwickl, Benjamin M.; Hirokawa, Takako; Finkelstein, Noah; Lewandowski, H. J.

    2014-06-01

    In response to national calls to better align physics laboratory courses with the way physicists engage in research, we have developed an epistemology and expectations survey to assess how students perceive the nature of physics experiments in the contexts of laboratory courses and the professional research laboratory. The Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS) evaluates students' epistemology at the beginning and end of a semester. Students respond to paired questions about how they personally perceive doing experiments in laboratory courses and how they perceive an experimental physicist might respond regarding their research. Also, at the end of the semester, the E-CLASS assesses a third dimension of laboratory instruction, students' reflections on their course's expectations for earning a good grade. By basing survey statements on widely embraced learning goals and common critiques of teaching labs, the E-CLASS serves as an assessment tool for lab courses across the undergraduate curriculum and as a tool for physics education research. We present the development, evidence of validation, and initial formative assessment results from a sample that includes 45 classes at 20 institutions. We also discuss feedback from instructors and reflect on the challenges of large-scale online administration and distribution of results.

  14. Tilted wheel satellite attitude control with air-bearing table experimental results

    Science.gov (United States)

    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.

  15. Attitudes towards the Government’s Remembrance Policy in Poland: Results of an Experimental Study

    Directory of Open Access Journals (Sweden)

    Wawrzyński Patryk

    2015-12-01

    Full Text Available The paper presents the results of an experimental study of Polish students’ attitudes towards their government’s remembrance policy (or, in other words, the intentional narration and interpretation of the past by the government. It includes four parts: a justification of why remembrance is a significant political asset in post-Communist Poland; a classification of remembrance policy instruments; a presentation of general results of the study; and a discussion of participants’ attitudes to particular policy instruments. In our assessment of the general results, we discuss three types of collected data: the results of the initial measurement of attitudes; the results of measurement after the manipulation of emotions (neutral vs. positive vs. negative and commitment (no commitment vs. low commitment; and the results in terms of attitude change. In the section on attitudes to particular instruments, we compare participants’ support for different commemorative actions with their support for the governments’ dominant role in the popularising of remembrance narratives. The study’s results lead us to formulate three conclusions about the relationships between attitudes to the policy and Polish political culture.

  16. An Experimental Investigation of the Droplet Deformation Process Resulting from Binary Collisions of a Viscous Fluid

    Science.gov (United States)

    Willis, Keeney; Orme, Melissa

    1997-11-01

    An experimental investigation of the collisional dynamics of equal sized drops of a viscous, silicone based oil, DC 200, has been conducted for head-on impacts in a vacuum. Results show that the range of droplet Weber numbers necessary to describe the boundaries between permanent coalescence and what has been previously described as reflexive separation, is several orders of magnitude higher than has been reported in studies involving water and hydrocarbon fuel droplets. Energy dissipation during the deformation process has been measured, and the results show a wide discrepancy with available theory. Detailed observations of the post-impact deformation process reveals that in this case, the formation of multiple drops is due solely to the growth of Rayleigh instabilities on the extended fluid ligament.

  17. Comparison of results of experimental research with numerical calculations of a model one-sided seal

    Directory of Open Access Journals (Sweden)

    Joachimiak Damian

    2015-06-01

    Full Text Available 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.

  18. Experimental results for improving the matrix condition using a hybrid optical system.

    Science.gov (United States)

    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.

  19. EQUIVALENT EXCITATION METHOD FOR VIBRATION ISOLATION DESIGN:THEORETICAL ANALYSIS AND EXPERIMENTAL RESULTS

    Institute of Scientific and Technical Information of China (English)

    Huo Rui; Shi Yin

    2005-01-01

    In view of difficulties concerned with direct measurement of excitations inside source equipments and their significant influence on vibration isolation effectiveness, a dynamical model, for vibration isolation of a rigid machine with six-degree-of-freedom mounted on a flexible foundation through multiple mounts, is analyzed, in which the complicated and multiple disturbances inside the machine are described as an equivalent excitation spectrum. And a method for the estimation of the equivalent excitation spectrum according to system dynamic responses is discussed for the quantitative prediction of isolation effectiveness.Both theoretical analysis and experimental results are demonstrated. Further work shows the quantitative prediction of transmitted power flow in a flexible vibration isolation experiment system using the proposed equivalent excitation spectrum method, by comparison with its testing results.

  20. Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results

    Directory of Open Access Journals (Sweden)

    Tor A. Johansen

    2004-01-01

    Full Text Available A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerged vessel with a moonpool shows that wave synchronization leads to significant improvements in performance. Depending on the sea state and payload, the results indicate that the reduction in the standard deviation of the wire tension may be up to 50

  1. The 3D structure of the hadrons: recents results and experimental program at Jefferson Lab

    Directory of Open Access Journals (Sweden)

    Muñoz Camacho C.

    2014-04-01

    Full Text Available The understanding of Quantum Chromodynamics (QCD at large distances still remains one of the main outstanding problems of nuclear physics. Studying the internal structure of hadrons provides a way to probe QCD in the non-perturbative domain and can help us unravel the internal structure of the most elementary blocks of matter. Jefferson Lab (JLab has already delivered results on how elementary quarks and gluons create nucleon structure and properties. The upgrade of JLab to 12 GeV will allow the full exploration of the valence-quark structure of nucleons and the extraction of real threedimensional pictures. I will present recent results and review the future experimental program at JLab.

  2. Subionospehric VLF perturbations of red sprites: 3D FDTD modeling and experimental results

    Science.gov (United States)

    Iwamoto, M.; Hobara, Y.; Ohta, K.; Minatohara, T.; Otsuyama, T.; Hayakawa, M.

    2012-04-01

    Majority of red sprites occurs in association with large positive cloud to ground discharges. Although the red sprite consists of highly ionized structure, physical properties of the ionization columns such as electron density and spatial extent have not understood well. In this paper 3D finite-difference time-domain (FDTD) method carried out to compute the subionospheric VLF signal perturbations due to the sprite ionization columns. Spatial scales of columns are determined by the sprite images obtained from our optical observations during winter lightning activities over the sea of Japan. Numerical results indicate that the multiple sprites generate the complicated scattering pattern of the VLF transmitter waves depending on special orientation and extent of sprite ionization columns. Spatial dependence of the scattered amplitude are compared with those from the experimental results of VLF observation network.

  3. Soil gas and radon entry into a simple test structure: Comparison of experimental and modelling results

    DEFF Research Database (Denmark)

    Andersen, C.E.; Søgaard-Hansen, J.; Majborn, B.

    1994-01-01

    A radon test structure has been established at a field site at Riso National Laboratory. Measurements have been made of soil gas entry rates, pressure couplings and radon depletion. The experimental results have been compared with results obtained from measured soil parameters and a two......-dimensional steady-state numerical model of Darcy flow and combined diffusive and advective transport of radon. For most probe locations, the calculated values of the pressure couplings and the radon depletion agree well with the measured values, thus verifying important elements of the Darcy flow approximation......, and the ability of the model to treat combined diffusive and advective transport of radon. However, the model gives an underestimation of the soil gas entry rate. Even if it is assumed that the soil has a permeability equal to the highest of the measured values, the model underestimates the soil gas entry rate...

  4. Follow-the-leader control for a train-like-vehicle. Implementation and experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Micaelli, A.; Louveau, F.; Sabourin, D. [CEA Centre d`Etudes de Grenoble, 38 (France). Direction des Technologies Avancees; Canudas de Wit, C.; Ndoudi-Likoho, A.D. [Laboratoire d`Automatique de Grenoble, 38 - Saint-martin d`Heres (France)

    1994-12-31

    This paper presents some practical implementation aspects and results of a particular control law dedicated to Train-Like-Vehicles (TLV) for trajectory tracking purpose. The CEA`s demonstrator consists of two modules. It is a partial but representative mockup of a future 4-modules vehicle devoted to maintenance and intervention in nuclear plants, which is now on development within the frame of the Teleman/MESSINA project. The main principles of the control are first recalled; then the reference trajectory and its on line computation, and the robot`s reference configuration are investigated; tuning the control parameters and control saturation are studied. Experimental and successful results of a real implementation on a TLV mockup are given and discussed. 10 figs., 3 refs.

  5. Dimethyl Ether: New Advances in Wear Testing: Theoretical and Experimental Results

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Sorenson, Spencer C; Jakobsen, J.;

    2003-01-01

    ) on the ball. Up to now, all analyses indicated that fuel viscosity influences the wear scar size and fuel performance in full-scale pumps. The wear scar size could then be a result of hydrodynamic lubrication (at least a significant part of it) and not of boundary lubrication as it was the original intention...... viscosity sensibility issue is seriously aggravated for this fuel. Molecular dynamics calculations involving straight alkanes with lengths from 3 to 14 carbon atoms have been performed. The model is based on simple inter-atomic and surface interactions and it simulates an asperity contact between curved...... surfaces with long-range elasticity. This last property has enabled the model to correlate well with experimental results. The outcome of the alkane calculations indicates that the longer ones lubricate better than the shorts ones but not necessarily because of viscosity differences. The reason is more...

  6. Protobacco Media Exposure and Youth Susceptibility to Smoking Cigarettes, Cigarette Experimentation, and Current Tobacco Use among US Youth.

    Directory of Open Access Journals (Sweden)

    Erika B Fulmer

    Full Text Available Youth are exposed to many types of protobacco influences, including smoking in movies, which has been shown to cause initiation. This study investigates associations between different channels of protobacco media and susceptibility to smoking cigarettes, cigarette experimentation, and current tobacco use among US middle and high school students.By using data from the 2012 National Youth Tobacco Survey, structural equation modeling was performed in 2013. The analyses examined exposure to tobacco use in different channels of protobacco media on smoking susceptibility, experimentation, and current tobacco use, accounting for perceived peer tobacco use.In 2012, 27.9% of respondents were never-smokers who reported being susceptible to trying cigarette smoking. Cigarette experimentation increased from 6.3% in 6th grade to 37.1% in 12th grade. Likewise, current tobacco use increased from 5.2% in 6th grade to 33.2% in 12th grade. Structural equation modeling supported a model in which current tobacco use is associated with exposure to static advertising through perception of peer use, and by exposure to tobacco use depicted on TV and in movies, both directly and through perception of peer use. Exposure to static advertising appears to directly increase smoking susceptibility but indirectly (through increased perceptions of peer use to increase cigarette experimentation. Models that explicitly incorporate peer use as a mediator can better discern the direct and indirect effects of exposure to static advertising on youth tobacco use initiation.These findings underscore the importance of reducing youth exposure to smoking in TV, movies, and static advertising.

  7. Heat Transfer Enhancement for Finned-Tube Heat Exchangers with Vortex Generators: Experimental and Numerical Results

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Folding and necking across the scales: a review of theoretical and experimental results and their applications

    Science.gov (United States)

    Markus Schmalholz, Stefan; Mancktelow, Neil Sydney

    2016-10-01

    The shortening and extension of mechanically layered ductile rock generates folds and pinch-and-swell structures (also referred to as necks or continuous boudins), which result from mechanical instabilities termed folding and necking, respectively. Folding and necking are the preferred deformation modes in layered rock because the corresponding mechanical work involved is less than that associated with a homogeneous deformation. The effective viscosity of a layered rock decreases during folding and necking, even when all material parameters remain constant. This mechanical softening due to viscosity decrease is solely the result of fold and pinch-and-swell structure development and is hence termed structural softening (or geometric weakening). Folding and necking occur over the whole range of geological scales, from microscopic up to the size of lithospheric plates. Lithospheric folding and necking are evidence for significant deformation of continental plates, which contradicts the rigid-plate paradigm of plate tectonics. We review here some theoretical and experimental results on folding and necking, including the lithospheric scale, together with a short historical overview of research on folding and necking. We focus on theoretical studies and analytical solutions that provide the best insight into the fundamental parameters controlling folding and necking, although they invariably involve simplifications. To first order, the two essential parameters to quantify folding and necking are the dominant wavelength and the corresponding maximal amplification rate. This review also includes a short overview of experimental studies, a discussion of recent developments involving mainly numerical models, a presentation of some practical applications of theoretical results, and a summary of similarities and differences between folding and necking.

  9. Experimental Verification of Overlimiting Current by Surface Conduction and Electro-osmotic Flow in Microchannels

    CERN Document Server

    Nam, Sungmin; Heo, Joonseong; Lim, Geunbae; Bazant, Martin Z; Sung, Gunyong; Kim, Sung Jae

    2014-01-01

    Possible mechanisms of overlimiting current in unsupported electrolytes, exceeding diffusion limitation, have been intensely studied for their fundamental significance and applications to desalination, separations, sensing, and energy storage. In bulk membrane systems, the primary physical mechanism is electro-convection, driven by electro-osmotic instability on the membrane surface. It has recently been predicted that confinement by charged surfaces in microchannels or porous media favors two new mechanisms, electro-osmotic flow (EOF) and surface conduction (SC), driven by large electric fields in the depleted region acting on the electric double layers on the sidewalls. Here, we provide the first direct evidence for the transition from SC to EOF above a critical channel height, using in situ particle tracking and current-voltage measurements in a micro/nanofluidic device. The dependence of the over-limiting conductance on channel depth (d) is consistent with theoretical predictions, scaling as d^-1 for SC a...

  10. Foreign Languages in Vienna Primary Schools – in Mainstream Education and in Current Experimental Models

    Directory of Open Access Journals (Sweden)

    Renate Seebauer

    2015-05-01

    Full Text Available Starting with a short retrospective and an overview of the incorporation of foreign language learning into the Austrian curriculum for primary schools the paper in hand describes the current situation of foreign language teaching in primary schools as well as various current models of foreign language education in primary schools in Vienna (school year 1 to 4. In terms of objectives these models exceed the requirements of the curriculum of the formal education system or regard themselves as quantitative and qualitative enrichment. They follow different didactic approaches and/or site-specific characteristics and needs. The formulation of basic skills is to be understood as an attempt to find a common basis of output indicators and to facilitate the transition to secondary education. Although English is the most commonly chosen resp. offered language the paper also refers to school experiments that focus on Romance or Slavic languages or on languages of Austra’s neighbouring countries.

  11. Experimental investigation of quasiperiodic-chaotic-quasiperiodic-chaotic transition in a direct current magnetron sputtering plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sabavath, Gopi Kishan; Banerjee, I.; Mahapatra, S. K., E-mail: skmahapatra@bitmesra.ac.in [Plasma Laboratory, Department of Physics, Birla Institute of Technology-Mesra, Ranchi 835215 (India); Shaw, Pankaj Kumar; Sekar Iyengar, A. N. [Plasma Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India)

    2015-08-15

    Floating potential fluctuations from a direct current magnetron sputtering plasma have been analysed using time series analysis techniques like phase space plots, power spectra, frequency bifurcation plot, etc. The system exhibits quasiperiodic-chaotic-quasiperiodic-chaotic transitions as the discharge voltage was increased. The transitions of the fluctuations, quantified using the largest Lyapunov exponent, have been corroborated by Hurst exponent and the Shannon entropy. The Shannon entropy is high for quasiperiodic and low for chaotic oscillations.

  12. Photospheric Current Spikes and Their Possible Association with Flares - Results from an HMI Data Driven Model

    Science.gov (United States)

    Goodman, Michael; Kwan, Chiman; Ayhan, Bulent; Shang, Eric L.

    2016-01-01

    A data driven, near photospheric magnetohydrodynamic model predicts spikes in the horizontal current density, and associated resistive heating rate per unit volume Q. The spikes appear as increases by orders of magnitude above background values in neutral line regions (NLRs) of active regions (ARs). The largest spikes typically occur a few hours to a few days prior to M or X flares. The spikes correspond to large vertical derivatives of the horizontal magnetic field. The model takes as input the photospheric magnetic field observed by the Helioseismic & Magnetic Imager (HMI) on the Solar Dynamics Observatory (SDO) satellite. This 2.5 D field is used to determine an analytic expression for a 3 D magnetic field, from which the current density, vector potential, and electric field are computed in every AR pixel for 14 ARs. The field is not assumed to be force-free. The spurious 6, 12, and 24 hour Doppler periods due to SDO orbital motion are filtered out of the time series of the HMI magnetic field for each pixel using a band pass filter. The subset of spikes analyzed at the pixel level are found to occur on HMI and granulation scales of 1 arcsec and 12 minutes. Spikes are found in ARs with and without M or X flares, and outside as well as inside NLRs, but the largest spikes are localized in the NLRs of ARs with M or X flares. The energy to drive the heating associated with the largest current spikes comes from bulk flow kinetic energy, not the electromagnetic field, and the current density is highly non-force free. The results suggest that, in combination with the model, HMI is revealing strong, convection driven, non-force free heating events on granulation scales, and that it is plausible these events are correlated with subsequent M or X flares. More and longer time series need to be analyzed to determine if such a correlation exists. Above an AR dependent threshold value of Q, the number of events N(Q) with heating rates greater than or equal to Q obeys a scale

  13. Carbon Dioxide Sequestration by Direct Mineral Carbonation: Results from Recent Studies and Current Status

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, William K.; Dahlin, David C.; Nilsen, David N.; Rush, G.E.; Walters, Richard P.; Turner, Paul C.

    2001-01-01

    Direct mineral carbonation has been investigated as a process to convert gaseous CO2 into a geologically stable, solid final form. The process utilizes a solution of sodium bicarbonate (NaHCO3), sodium chloride (NaCl), and water, mixed with a mineral reactant, such as olivine (Mg2SiO4) or serpentine [Mg3Si2O5(OH)4]. Carbon dioxide is dissolved into this slurry, by diffusion through the surface and gas dispersion within the aqueous phase. The process includes dissolution of the mineral and precipitation of magnesium carbonate (MgCO3) in a single unit operation. Optimum results have been achieved using heat pretreated serpentine feed material, with a surface area of roughly 19 m2 per gram, and high partial pressure of CO2 (PCO2). Specific conditions include: 155?C; PCO2=185 atm; 15% solids. Under these conditions, 78% stoichiometric conversion of the silicate to the carbonate was achieved in 30 minutes. Studies suggest that the mineral dissolution rate is primarily surface controlled, while the carbonate precipitation rate is primarily dependent on the bicarbonate concentration of the slurry. Current studies include further examination of the reaction pathways, and an evaluation of the resource potential for the magnesium silicate reactant, particularly olivine. Additional studies include the examination of various pretreatment options, the development of a continuous flow reactor, and an evaluation of the economic feasibility of the process.

  14. Estimation of the yield of poplars in plantations of fast-growing species within current results

    Directory of Open Access Journals (Sweden)

    Martin Fajman

    2009-01-01

    Full Text Available Current results are presented of allometric yield estimates of the poplar short rotation coppice. According to a literature review it is obvious that yield estimates, based on measurable quantities of a growing stand, depend not only on the selected tree specie or its clone, but also on the site location. The Jap-105 poplar clone (P. nigra x P. maximowiczii allometric relations were analyzed by regression methods aimed at the creation of the yield estimation methodology at a testing site in Domanínek. Altogether, the twelve polynomial dependences of particular measured quantities approved the high empirical data conformity with the tested regression model (correlation index from 0.9033 to 0.9967. Within the forward stepwise regression, factors were selected, which explain best examined estimates of the total biomass DM; i.e. d.b.h. and stem height. Furthermore, the KESTEMONT’s (1971 mo­del was verified with a satisfying conformity as well. Approving presented yield estimation methods, the presented models will be checked in a large-scale field trial.

  15. Current and future delivery of diagnostic electron microscopy in the UK: results of a national survey.

    Science.gov (United States)

    de Haro, Tracey; Furness, Peter

    2012-04-01

    Electron microscopy (EM) remains essential to delivering several specialist areas of diagnosis, especially the interpretation of native renal biopsies. However, there is anecdotal evidence of EM units struggling to survive, for a variety of reasons. The authors sought to obtain objective evidence of the extent and the causes of this problem. An online survey was undertaken of Fellows of the Royal College of Pathologists who use EM in diagnosis. A significant number of EM units anticipate having to close and hence outsource their EM work in the coming years. Yet most existing units are working to full capacity and would be unable to take on the substantial amounts of extra work implied by other units outsourcing their needs. Equipment and staffing are identified by most EM units as the major barriers to growth and are also the main reasons cited for units facing potential closure. In the current financial climate it seems unlikely that units will be willing to make the large investment in equipment and staff needed to take on extra work, unless they can be reasonably confident of an acceptable financial return as a result of increased external referral rates. The case is thus made for a degree of national coordination of the future provision of this specialist service, possibly through the National Commissioning Group or the new National Commissioning Board. Without this, the future of diagnostic EM services in the UK is uncertain. Its failure would pose a threat to good patient care.

  16. STUDENT SATISFACTION, RESULTANT OF MARKETING ORIENTATION OF UNIVERSITY UNDER CURRENT CONDITIONS

    Directory of Open Access Journals (Sweden)

    Florentina DINESCU

    2012-12-01

    Full Text Available The purpose of this work is to present a relevant aspect of marketing approach of the activities carried by universities, respectively knowing, understanding and satisfying students’ needs, the main consumer category of the university product, in the conditions of current market of high education institutions. The universities are put in the position to find solutions to the problems caused by the stakeholders’ characteristics and by the existing competition on the educational market. The approach of marketing orientation in the university implies adapting the educational and scientific research step to create for the institution a brand image as a warranty of its sustainability on a competitive market by considering the needs and expectations of students. The conclusion is that there is a wide specialized literature that shows models that allow an adequate quantification of the students’ satisfaction as a resultant of concerning the insurance of high education quality by using univeristy marketing tools. Starting from the specialized literature, in the work was handled the quantification of the students’ satisfaction that have completed Bachelor and Master cycle in order to improve the activity of the university

  17. HIV-1 Tat protein increases microglial outward K(+ current and resultant neurotoxic activity.

    Directory of Open Access Journals (Sweden)

    Jianuo Liu

    Full Text Available Microglia plays a crucial role in the pathogenesis of HIV-1-associated neurocognitive disorders. Increasing evidence indicates the voltage-gated potassium (Kv channels are involved in the regulation of microglia function, prompting us to hypothesize Kv channels may also be involved in microglia-mediated neurotoxic activity in HIV-1-infected brain. To test this hypothesis, we investigated the involvement of Kv channels in the response of microglia to HIV-1 Tat protein. Treatment of rat microglia with HIV-1 Tat protein (200 ng/ml resulted in pro-inflammatory microglial activation, as indicated by increases in TNF-α, IL-1β, reactive oxygen species, and nitric oxide, which were accompanied by enhanced outward K(+ current and Kv1.3 channel expression. Suppression of microglial Kv1.3 channel activity, either with Kv1.3 channel blockers Margatoxin, 5-(4-Phenoxybutoxypsoralen, or broad-spectrum K(+ channel blocker 4-Aminopyridine, or by knockdown of Kv1.3 expression via transfection of microglia with Kv1.3 siRNA, was found to abrogate the neurotoxic activity of microglia resulting from HIV-1 Tat exposure. Furthermore, HIV-1 Tat-induced neuronal apoptosis was attenuated with the application of supernatant collected from K(+ channel blocker-treated microglia. Lastly, the intracellular signaling pathways associated with Kv1.3 were investigated and enhancement of microglial Kv1.3 was found to correspond with an increase in Erk1/2 mitogen-activated protein kinase activation. These data suggest targeting microglial Kv1.3 channels may be a potential new avenue of therapy for inflammation-mediated neurological disorders.

  18. Structural and vibrational study of graphene oxide via coronene based models: theoretical and experimental results

    Science.gov (United States)

    Almeida de Mendonça, João Paulo; Henrique de Lima, Alessandro; Amaral Junqueira, Georgia Maria; Gianini Quirino, Welber; Legnani, Cristiano; Oliveira Maciel, Indhira; Sato, Fernando

    2016-05-01

    We use the Coronene (C24H12), a simple and finite molecule, to make a model to study the spectroscopic and structural alterations generated by oxygenated groups in graphene oxide (GO). Based on the Lerf-Klinowski model, we chose the hydroxyl [OH-], the carboxyl [COOH-] and the epoxy [the ring C2O inside the molecule] as our radicals of interest and study their collective and isolated effects. We perform geometry optimization, vibrational IR (via AM1 and DFT-B3LYP) and Raman spectra (via DFT-B3LYP) of a series of functionalized coronene molecules. As results, we obtain some useful data for the analysis of IR and Raman spectra of GO, which facilitate the understanding and identification of the peaks found in the experiment. Finally, we suggest a new model to study GO, producing an accurate signature when compared to our experimental data. Such molecule shows in more details of the structural effects caused by functionalization when compared to experimental data.

  19. RC Beams Strengthened with Mechanically Fastened Composites: Experimental Results and Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Enzo Martinelli

    2014-03-01

    Full Text Available The use of mechanically-fastened fiber-reinforced polymer (MF-FRP systems has recently emerged as a competitive solution for the flexural strengthening of reinforced concrete (RC beams and slabs. An overview of the experimental research has proven the effectiveness and the potentiality of the MF-FRP technique which is particularly suitable for emergency repairs or when the speed of installation and immediacy of use are imperative. A finite-element (FE model has been recently developed by the authors with the aim to simulate the behavior of RC beams strengthened in bending by MF-FRP laminates; such a model has also been validated by using a wide experimental database collected from the literature. By following the previous study, the FE model and the assembled database are considered herein with the aim of better exploring the influence of some specific aspects on the structural response of MF-FRP strengthened members, such as the bearing stress-slip relationship assumed for the FRP-concrete interface, the stress-strain law considered for reinforcing steel rebars and the cracking process in RC members resulting in the well-known tension stiffening effect. The considerations drawn from this study will be useful to researchers for the calibration of criteria and design rules for strengthening RC beams through MF-FRP laminates.

  20. Experimentation with projectiles of flat retouch and their functional analysis results

    Directory of Open Access Journals (Sweden)

    María Amparo LABORDA MARTÍNEZ

    2016-07-01

    Full Text Available A varied repertoire of buildings of monumental architecture, which are located in the upper and middle basin of the Ebro valley, have been interpreted as collective graves of diachronic use along the III millennium BC. Numerous arrowheads have been recovered in the filling deposits of some burial chambers. Most of them have been registered among the skeletal remains, but only very few of them were nailed in bones of certain buried individuals. The purpose of this work is to reconstruct its function as projectiles through experimentation and traceology, with the aim of approaching to the meaning of these weapons in funerary contexts, and taking the arrowheads collections from the dolmens of Aizibita and Charracadía (Salado valley, Navarre as a reference. The experimental program developed has included the use of different morphologies of flint arrowheads of flat retouch which were propelled by bow. A session of shot has been carried out, during which the replicas were fired in the most adjusted way to the alleged prehistoric reality. A subsequent use-wear analysis has identified impact traces of macroscopic and microscopic nature. Issues relating to effectiveness, use and longevity of these lithic projectiles are addressed from the obtained results.

  1. Fate and Transport of Graphene Oxide in Granular Porous Media: Experimental Results and Modeling

    Science.gov (United States)

    Gao, Bin

    2014-05-01

    Although graphene oxide (GO) has been used in many applications to improve human life quality, its environmental fate and behavior are still largely unknown. In this work, a range of laboratory experiments were conducted to explore the aggregation, deposition, and transport mechanisms of GO nano-sheets in porous media under various conditions. Stability experimental data showed that both cation valence and pH showed significant effect on the aggregation of GO sheets. The measured critical coagulation concentrations were in good agreement with the predictions of the extended Schulze-Hardy rule. Sand column experimental results indicated that deposition and transport of GO in porous media were strongly dependent on solution ionic strength. Particularly, GO showed high mobility under low ionic strength conditions in both saturated and unsaturated columns. Increasing ionic strength dramatically increased the retention of GO in porous media, mainly through secondary-minimum deposition. Recovery rates of GO in unsaturated sand columns were lower than that in saturated columns under the same ionic strength conditions, suggesting moisture content also played an important role in the retention of GO in porous media. Findings from the bubble column experiments showed that the GO did not attach to the air-water interface, which is consistent with the XDLVO predictions. Additional retention mechanisms, such as film straining, thus could be responsible to the reduced mobility of GO in unsaturated porous media. The breakthrough curves of GO in saturated and unsaturated columns could be accurately simulated by an advection-dispersion-reaction model.

  2. Numerical and experimental study of local heat transfer enhancement in helically coiled pipes. Preliminary results.

    Science.gov (United States)

    Bozzoli, F.; Cattani, L.; Rainieri, S.; Zachár, A.

    2015-11-01

    In the last years, the attention of heat transfer equipments manufacturers turned toward helically coiled-tube heat exchangers, especially with regards to applications for viscous and/or particulate products. The recent progress achieved in numerical simulation motivated many research groups to develop numerical models for this kind of apparatuses. These models, intended both to improve the knowledge of the fundamental heat transfer mechanisms in curved geometries and to support the industrial design of this kind of apparatuses, are usually validated throughout the comparison with either theoretical or experimental evidences by considering average heat transfer performances. However, this approach doesn't guarantee that the validated models are able to reproduce local effects in details, which are so important in this kind of non-standard geometries. In the present paper a numerical model of convective heat transfer in coiled tubes for laminar flow regime was formulated and discussed. Its goodness was checked throughout the comparison with the latest experimental outcomes of Bozzoli et al. [1] in terms of convective heat flux distribution along the boundary of the duct, by ensuring the effectiveness of the model also in the description of local behaviours. Although the present paper reports only preliminary results of this simulation/validation process, it could be of interest for the research community because it proposes a novel approach that could be useful to validate many numerical models for nonstandard geometries.

  3. Experimental results obtained with the simulated cold moderator system. System characteristics and technical issues

    CERN Document Server

    Aso, T; Hino, R; Kaminaga, M; Kinoshita, H; Takahashi, T

    2002-01-01

    The Japan Atomic Energy Research Institute and the High Energy Accelerator Research Organization have been developing a Mega-Watt scale spallation target system. In the system, neutrons generated in a target are sorted out their energy to the proper values in liquid-hydrogen moderators. Then, the liquid-hydrogen is forced to circulate in order to suppress hydrogen temperature increase. In the operation of moderators, it is very important to establish a safety protection system against emergency shutdown of the accelerator or accidents of the cold moderator system. In order to obtain a technical data for design and safety review of the liquid-hydrogen system, we have fabricated an experimental apparatus simulated the cold moderator system using liquid nitrogen (max. 1.5 MPa, mini. 77 K) instead of liquid hydrogen. The experiments on a controllability of the system were carried out to investigate dynamic characteristics of the system. This report presents the experimental results and technical issues for the co...

  4. Non-linear spacecraft component parameters identification based on experimental results and finite element modelling

    Science.gov (United States)

    Vismara, S. O.; Ricci, S.; Bellini, M.; Trittoni, L.

    2016-06-01

    The objective of the present paper is to describe a procedure to identify and model the non-linear behaviour of structural elements. The procedure herein applied can be divided into two main steps: the system identification and the finite element model updating. The application of the restoring force surface method as a strategy to characterize and identify localized non-linearities has been investigated. This method, which works in the time domain, has been chosen because it has `built-in' characterization capabilities, it allows a direct non-parametric identification of non-linear single-degree-of-freedom systems and it can easily deal with sine-sweep excitations. Two different application examples are reported. At first, a numerical test case has been carried out to investigate the modelling techniques in the case of non-linear behaviour based on the presence of a free-play in the model. The second example concerns the flap of the Intermediate eXperimental Vehicle that successfully completed its 100-min mission on 11 February 2015. The flap was developed under the responsibility of Thales Alenia Space Italia, the prime contractor, which provided the experimental data needed to accomplish the investigation. The procedure here presented has been applied to the results of modal testing performed on the article. Once the non-linear parameters were identified, they were used to update the finite element model in order to prove its capability of predicting the flap behaviour for different load levels.

  5. Experimental results obtained with the simulated cold moderator system. System characteristics and technical issues

    Energy Technology Data Exchange (ETDEWEB)

    Aso, Tomokazu; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Takahashi, Toshio; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-12-01

    The Japan Atomic Energy Research Institute and the High Energy Accelerator Research Organization have been developing a Mega-Watt scale spallation target system. In the system, neutrons generated in a target are sorted out their energy to the proper values in liquid-hydrogen moderators. Then, the liquid-hydrogen is forced to circulate in order to suppress hydrogen temperature increase. In the operation of moderators, it is very important to establish a safety protection system against emergency shutdown of the accelerator or accidents of the cold moderator system. In order to obtain a technical data for design and safety review of the liquid-hydrogen system, we have fabricated an experimental apparatus simulated the cold moderator system using liquid nitrogen (max. 1.5 MPa, mini. 77 K) instead of liquid hydrogen. The experiments on a controllability of the system were carried out to investigate dynamic characteristics of the system. This report presents the experimental results and technical issues for the construction of a practical liquid-hydrogen moderator system of the Mega-Watt scale target system. (author)

  6. Theory, simulation and experimental results of the acoustic detection of magnetization changes in superparamagnetic iron oxide

    Directory of Open Access Journals (Sweden)

    Borgert Jörn

    2011-06-01

    Full Text Available Abstract Background Magnetic Particle Imaging is a novel method for medical imaging. It can be used to measure the local concentration of a tracer material based on iron oxide nanoparticles. While the resulting images show the distribution of the tracer material in phantoms or anatomic structures of subjects under examination, no information about the tissue is being acquired. To expand Magnetic Particle Imaging into the detection of soft tissue properties, a new method is proposed, which detects acoustic emissions caused by magnetization changes in superparamagnetic iron oxide. Methods Starting from an introduction to the theory of acoustically detected Magnetic Particle Imaging, a comparison to magnetically detected Magnetic Particle Imaging is presented. Furthermore, an experimental setup for the detection of acoustic emissions is described, which consists of the necessary field generating components, i.e. coils and permanent magnets, as well as a calibrated microphone to perform the detection. Results The estimated detection limit of acoustic Magnetic Particle Imaging is comparable to the detection limit of magnetic resonance imaging for iron oxide nanoparticles, whereas both are inferior to the theoretical detection limit for magnetically detected Magnetic Particle Imaging. Sufficient data was acquired to perform a comparison to the simulated data. The experimental results are in agreement with the simulations. The remaining differences can be well explained. Conclusions It was possible to demonstrate the detection of acoustic emissions of magnetic tracer materials in Magnetic Particle Imaging. The processing of acoustic emission in addition to the tracer distribution acquired by magnetic detection might allow for the extraction of mechanical tissue parameters. Such parameters, like for example the velocity of sound and the attenuation caused by the tissue, might also be used to support and improve ultrasound imaging. However, the method

  7. Objective assessment of vocal hyperfunction: an experimental framework and initial results.

    Science.gov (United States)

    Hillman, R E; Holmberg, E B; Perkell, J S; Walsh, M; Vaughan, C

    1989-06-01

    This report describes the experimental design and initial results of an ongoing clinical investigation of voice disorders. Its major focus is the development and use of quantitative measures to provide objective descriptions of conditions referred to as "vocal hyperfunction." The experimental design for this project is based on a descriptive theoretical framework, which holds that there are different types and stages of hyperfunctionally related voice disorders. Data consist of indirect measures derived from noninvasive aerodynamic and acoustic recordings including (a) parameters derived from inverse filtered approximations of the glottal air flow waveform; (b) estimates of transglottal pressure, average glottal air flow, glottal resistance and vocal efficiency; and (c) measures of vocal intensity and fundamental frequency. Initial results (based on comparisons among 15 voice patients and 45 normal speakers) support major assumptions that underlie the theoretical framework, and indicate that the measurement approach being utilized is capable of differentiating hyperfunctional from normal voices and hyperfunctional conditions from one another. Organic manifestations of vocal hyperfunction (nodules, polyps, contact ulcers) are accompanied by abnormally high values for the glottal waveform parameters of AC flow and maximum flow declination rate, suggesting increased potential for vocal fold trauma due to high vocal fold closure velocities and collision forces. In contrast, nonorganic manifestations of hyperfunction (functional disorders) tend to be associated with abnormally high levels of unmodulated DC flow, without high values for AC flow and maximum flow declination rate, suggesting reduced potential for vocal fold trauma. Measures also suggest different underlying mechanisms for nodules and polyps as compared to contact ulcers. Results are discussed relative to predictions based on the theoretical framework for vocal hyperfunction.

  8. Smectite clays in Mars soil - Evidence for their presence and role in Viking biology experimental results

    Science.gov (United States)

    Banin, A.; Rishpon, J.

    1979-01-01

    Evidence for the presence of smectite clays in Martian soils is reviewed and results of experiments with certain active clays simulating the Viking biology experiments are reported. Analyses of Martian soil composition by means of X-ray fluorescence spectrometry and dust storm spectroscopy and Martian geological history strongly suggest the presence of a mixture of weathered ferro-silicate minerals, mainly nontronite and montmorillonite, accompanied by soluble sulphate salts, as major constituents. Samples of montmorillonite and nontronite incubated with (C-14)-formate or the radioactive nutrient medium solution used in the Viking Labeled Release experiment, were found to produce patterns of release of radioactive gas very similar to those observed in the Viking experiments, indicating the iron-catalyzed decomposition of formate as the reaction responsible for the Viking results. The experimental results of Hubbard (1979) simulating the results of the Viking Pyrolytic Release experiment using iron montmorillonites are pointed out, and it is concluded that many of the results of the Viking biology experiments can be explained in terms of the surface activity of smectite clays in catalysis and adsorption.

  9. Results of Experiments on Convective Precipitation Enhancement in the Camaguey Experimental Area, Cuba.

    Science.gov (United States)

    Koloskov, Boris; Zimin, Boris; Beliaev, Vitaly; Seregin, Yury; Chernikov, Albert; Petrov, Victor; Valdés, Mario; Martínez, Daniel; Pérez, Carlos A.; Puente, Guillermo

    1996-09-01

    Experiments on randomized seeding of individual convective clouds and cloud clusters were conducted in the Camaguey experimental area, Cuba, from 1985 through 1990 in order to elucidate whether cold-cloud dynamic seeding can be used to augment convective rainfall. An information measuring system was set up, and primary tools included three instrumented aircraft (AN-26, AN-12 CYCLONE, IL-14), MRL-5 and ARS-3 radars, a system for radiosounding, two special rain gauge networks, and surface weather stations.A total of 232 randomized experiments were carried out during this experimentation period, and 117 individual clouds and 115 cloud clusters were studied during 136 `go' days. Pyrotechnic flares containing silver iodide were ejected in a selected cloud when the seeder aircraft was flying through its top. The seeding effects were monitored by the MRL-5 radar, which was equipped with an automated system for digital processing of data.A total of 46 convective clouds, 29 seeded and 17 nonseeded, were studied during an exploratory experiment in 1985. Analyses of the radar properties of seeded and nonseeded clouds have indicated that the response of convective clouds to AgI seeding is dependent on their type, and the treatment within the range of cloud tops from 6 to 8 km—that is, at top temperatures between 10° and 20°C, is found to increase their maximum height by 13% and the lifetime by 30%, and to enhance rainfall.A confirmatory phase of the experiment in the Camaguey experimental area was conducted during 1986 90. A total of 46 individual convective clouds, 24 seeded and 22 nonseeded, were identified, and their properties were determined using three-dimensional radar data. The results have shown that the AgI seeding of growing clouds with top temperatures over the range from 10° to 20°C increases their lifetime by 24%, maximum height by 9%, area by 64%, and rain volume by 120%, as compared to unseeded clouds. The lifetime, area, and rainfall results are

  10. Experimental results of fingerprint comparison validity and reliability: A review and critical analysis.

    Science.gov (United States)

    Haber, Ralph Norman; Haber, Lyn

    2014-09-01

    Our purpose in this article is to determine whether the results of the published experiments on the accuracy and reliability of fingerprint comparison can be generalized to fingerprint laboratory casework, and/or to document the error rate of the Analysis-Comparison-Evaluation (ACE) method. We review the existing 13 published experiments on fingerprint comparison accuracy and reliability. These studies comprise the entire corpus of experimental research published on the accuracy of fingerprint comparisons since criminal courts first admitted forensic fingerprint evidence about 120years ago. We start with the two studies by Ulery, Hicklin, Buscaglia and Roberts (2011, 2012), because they are recent, large, designed specifically to provide estimates of the accuracy and reliability of fingerprint comparisons, and to respond to the criticisms cited in the National Academy of Sciences Report (2009). Following the two Ulery et al. studies, we review and evaluate the other eleven experiments, considering problems that are unique to each. We then evaluate the 13 experiments for the problems common to all or most of them, especially with respect to the generalizability of their results to laboratory casework. Overall, we conclude that the experimental designs employed deviated from casework procedures in critical ways that preclude generalization of the results to casework. The experiments asked examiner-subjects to carry out their comparisons using different responses from those employed in casework; the experiments presented the comparisons in formats that differed from casework; the experiments enlisted highly trained examiners as experimental subjects rather than subjects drawn randomly from among all fingerprint examiners; the experiments did not use fingerprint test items known to be comparable in type and especially in difficulty to those encountered in casework; and the experiments did not require examiners to use the ACE method, nor was that method defined

  11. Is Current CMBR Temperature: The Scale Independent Quantum Gravitational Result of Black Hole Cosmology?

    Science.gov (United States)

    Seshavatharam, U. V. S.; Lakshminarayana, S.

    If one is willing to consider the current cosmic microwave back ground temperature as a quantum gravitational effect of the evolving primordial cosmic black hole (universe that constitutes dynamic space-time and exhibits quantum behavior) automatically general theory of relativity and quantum mechanics can be combined into a `scale independent' true unified model of quantum gravity. By considering the `Planck mass' as the initial mass of the baby Hubble volume, past and current physical and thermal parameters of the cosmic black hole can be understood. Current rate of cosmic black hole expansion is being stopped by the microscopic quantum mechanical lengths. In this new direction authors observed 5 important quantum mechanical methods for understanding the current cosmic deceleration. To understand the ground reality of current cosmic rate of expansion, sensitivity and accuracy of current methods of estimating the magnitudes of current CMBR temperature and current Hubble constant must be improved and alternative methods must be developed. If it is true that galaxy constitutes so many stars, each star constitutes so many hydrogen atoms and light is coming from the excited electron of galactic hydrogen atom, then considering redshift as an index of `whole galaxy' receding may not be reasonable. During cosmic evolution, at any time in the past, in hydrogen atom emitted photon energy was always inversely proportional to the CMBR temperature. Thus past light emitted from older galaxy's excited hydrogen atom will show redshift with reference to the current laboratory data. As cosmic time passes, in future, the absolute rate of cosmic expansion can be understood by observing the rate of increase in the magnitude of photon energy emitted from laboratory hydrogen atom. Aged super novae dimming may be due to the effect of high cosmic back ground temperature. Need of new mathematical methods & techniques, computer simulations, advanced engineering skills seem to be essential

  12. An Experimental Investigation of Passive Variable-Pitch Vertical-Axis Ocean Current Turbine

    Directory of Open Access Journals (Sweden)

    Ridho Hantoro

    2011-04-01

    Full Text Available Vertical-axis hydrokinetic turbines with fixed pitch blades typically suffer from poor starting torque, low efficiency and shaking due to large fluctuations in both radial and tangential force with azimuth angle. Maximizing the turbine power output can be achieved only if the mechanism of generation of the hydrodynamic force on the blades is clearly identified and tools to design high-performance rotors are developed. This paper describes an initial experimental investigation to understand more of the performance on vertical-axis turbine related to the effect of fixed-pitch and passive variable-pitch application using airfoil NACA 0018. Comparative analysis according to aspects of rotation and tip speed ratios was discussed. Information regarding the changes of foil position in passive variable-pitch during rotation at a limited range of flow velocity variations test was obtained and analyzed.

  13. Current Status of Clinical and Experimental Researches on Cognitive Impairment in Diabetes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This article reviews the clinical and experimental researches on cognitive impairment related to diabetes in the recent decade. Most clinical studies indicate that the cognitive impairment in patients with type 1 diabetes mellitus is related to recurrent hypoglycemia closely. There is little research about whether or not hyperglycemia is related to cognitive impairment in patients with type 1 diabetes mellitus. Most studies indicate that the cognitive impairment in type 2 diabetes involves multiple factors through multiple mechanisms, including blood glucose, blood lipid, blood pressure, level of insulin, medication, chronic complication, etc. But, there has been no large-scale, multi-center, randomized controlled clinical trial in China recently. And what is more, some problems exist in this field of research, such as the lack of golden criterion of cognitive function measurement, different population of studied objects, and incomprehensive handling of confounding factors. Experimental studies found that hippocampal long-term potentiation (LTP) was impaired,which were manifested by impairment of spatial memory and decreased expression of LTP, but its relation to hyperglycemia, the duration of diabetes, learning and memory has always been differently reported by different researches. Thus, there are a lot of unknown things to be explored and studied in order to clarify its mechanism. TCM has abundant clinical experience in treating cerebral disease with medicine that enforces the kidney and promotes wit. However, there has been no research on treating diabetic cognitive impairment,which requires work to be done actively and TCM to be put into full play, in order to improve the treatment of diabetes and enhance living quality of patients.

  14. Spatial distribution of charged particles along the ion-optical axis in electron cyclotron resonance ion sources. Experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Panitzsch, Lauri

    2013-02-08

    The experimental determination of the spatial distribution of charged particles along the ion-optical axis in electron cyclotron resonance ion sources (ECRIS) defines the focus of this thesis. The spatial distributions of different ion species were obtained in the object plane of the bending magnet ({approx}45 cm downstream from the plasma electrode) and in the plane of the plasma electrode itself, both in high spatial resolution. The results show that each of the different ion species forms a bloated, triangular structure in the aperture of the plasma electrode. The geometry and the orientation of these structures are defined by the superposition of the radial and axial magnetic fields. The radial extent of each structure is defined by the charge of the ion. Higher charge states occupy smaller, more concentrated structures. The total current density increases towards the center of the plasma electrode. The circular and star-like structures that can be observed in the beam profiles of strongly focused, extracted ion beams are each dominated by ions of a single charge state. In addition, the spatially resolved current density distribution of charged particles in the plasma chamber that impinge on the plasma electrode was determined, differentiating between ions and electrons. The experimental results of this work show that the electrons of the plasma are strongly connected to the magnetic field lines in the source and thus spatially well confined in a triangular-like structure. The intensity of the electrons increases towards the center of the plasma electrode and the plasma chamber, as well. These electrons are surrounded by a spatially far less confined and less intense ion population. All the findings mentioned above were already predicted in parts by simulations of different groups. However, the results presented within this thesis represent the first (and by now only) direct experimental verification of those predictions and are qualitatively transferable to

  15. Anomalous attenuation of extraordinary waves in ionosphere heating experiments experimental results of 2000-2001

    CERN Document Server

    Zabotin, N A; Kovalenko, E S; Frolov, V L; Komrakov, G P; Mityakov, N A; Sergeev, E N

    2001-01-01

    Multiple scattering from artificial random irregularities HF-induced in the ionosphere F region causes significant attenuation of both ordinary and extraordinary radio waves together with the conventional anomalous absorption of ordinary waves due to their conversion into the plasma waves. To study in detail features of this effect, purposeful measurements of the attenuation of weak probing waves of the extraordinary polarization have been performed at the Sura heating facility. Characteristic scale lengths of the involved irregularities are ~0.1-1 km across the geomagnetic field lines. To determine the spectral characteristics of these irregularities from the extraordinary probing wave attenuation measurements, a simple procedure of the inverse problem solving has been implemented and some conclusions about the artificial irregularity features have been drawn. Theory and details of experiments have been stated earlier. This paper reports results of two experimental campaigns carried out in August 2000 and Ju...

  16. Gold Nanoparticles as Probes for Nano-Raman Spectroscopy: Preliminary Experimental Results and Modeling

    Directory of Open Access Journals (Sweden)

    V. Le Nader

    2012-01-01

    Full Text Available This paper presents an effective Tip-Enhanced Raman Spectrometer (TERS in backscattering reflection configuration. It combines a tip-probe nanopositioning system with Raman spectroscope. Specific tips were processed by anchoring gold nanoparticles on the apex of tapered optical fibers, prepared by an improved chemical etching method. Hence, it is possible to expose a very small area of the sample (~20 nm2 to the very strong local electromagnetic field generated by the lightning rod effect. This experimental configuration was modelled and optimised using the finite element method, which takes into account electromagnetic effects as well as the plasmon resonance. Finally, TERS measurements on single-wall carbon nanotubes were successfully performed. These results confirm the high Raman scattering enhancement predicted by the modelling, induced by our new nano-Raman device.

  17. Simulation and experimental results of optical and thermal modeling of gold nanoshells.

    Science.gov (United States)

    Ghazanfari, Lida; Khosroshahi, Mohammad E

    2014-09-01

    This paper proposes a generalized method for optical and thermal modeling of synthesized magneto-optical nanoshells (MNSs) for biomedical applications. Superparamagnetic magnetite nanoparticles with diameter of 9.5 ± 1.4 nm are fabricated using co-precipitation method and subsequently covered by a thin layer of gold to obtain 15.8 ± 3.5 nm MNSs. In this paper, simulations and detailed analysis are carried out for different nanoshell geometry to achieve a maximum heat power. Structural, magnetic and optical properties of MNSs are assessed using vibrating sample magnetometer (VSM), X-ray diffraction (XRD), UV-VIS spectrophotometer, dynamic light scattering (DLS), and transmission electron microscope (TEM). Magnetic saturation of synthesized magnetite nanoparticles are reduced from 46.94 to 11.98 emu/g after coating with gold. The performance of the proposed optical-thermal modeling technique is verified by simulation and experimental results.

  18. Numerical and Experimental Results of a Passive Free Yawing Downwind Wind Turbine

    DEFF Research Database (Denmark)

    Verelst, David Robert; Van Wingerden, Jan-Willem

    by coning angle, blade sweep, and blade flexibility using both numerical and experimental methods. The wind tunnel tests were organized in the Open Jet Facility of the TU Delft, and the thesis discusses the experiment’s design, construction, operation, and gives an analysis of the results. It provides...... the PhD study is a parametric blade sweep investigation for the NREL 5MW turbine, and a detailed study on load extrapolation methods based on aeroelastic simulations. It is concluded that the 3 bladed, free yawing, and downwind wind turbine can operate in a stable manner. However, numerical studies...... downwind concept is pursued in an attempt to increase the robustness of a wind turbine by eliminating the traditionally actively controlled, and sometimes failure prone yawing mechanism. Under certain conditions, such as for remote (off shore) and off grid applications, a decreased failure rate can...

  19. Angiography of the temporomandibular joint. Description of an experimental technique with initial results.

    Science.gov (United States)

    Takagi, R; Shimoda, T; Westesson, P L; Takahashi, A; Morris, T W; Sano, T; Moses, J J

    1994-10-01

    The vascular supply to the temporomandibular joint is not completely understood. To form a base for advancement in this area we developed a method for experimental angiography of the temporomandibular joint that was applied to fresh temporomandibular joint autopsy specimens. Via the external carotid artery the vessels were infused with a mixture of barium and an acrylic resin. The specimens were sectioned and contact radiographs were obtained. These showed the vascularity of the joint and the surrounding structures with great detail. Most of the vascular supply appears to come from the lateral and medial aspects of the condyle head and from the anterior and posterior disk attachments. The method was applied to both normal and abnormal joints and the results suggest that this method could be used to gather further understanding of the vascularity of the temporomandibular joint relative to disease.

  20. Benchmark of Space Charge Simulations and Comparison with Experimental Results for High Intensity, Low Energy Accelerators

    CERN Document Server

    Cousineau, Sarah M

    2005-01-01

    Space charge effects are a major contributor to beam halo and emittance growth leading to beam loss in high intensity, low energy accelerators. As future accelerators strive towards unprecedented levels of beam intensity and beam loss control, a more comprehensive understanding of space charge effects is required. A wealth of simulation tools have been developed for modeling beams in linacs and rings, and with the growing availability of high-speed computing systems, computationally expensive problems that were inconceivable a decade ago are now being handled with relative ease. This has opened the field for realistic simulations of space charge effects, including detailed benchmarks with experimental data. A great deal of effort is being focused in this direction, and several recent benchmark studies have produced remarkably successful results. This paper reviews the achievements in space charge benchmarking in the last few years, and discusses the challenges that remain.

  1. Model On DROID Response With Imperfect Trapping Tested On Experimental Results

    Science.gov (United States)

    Hijmering, R. A.; Kozorezov, A. G.; Verhoeve, P.; Martin, D. D. E.; Wigmore, J. K.; Venn, R.

    2009-12-01

    The DROID (Distributed Read-Out Imaging Detector) is being developed to overcome the limitation in sensitive area with the use of single STJ's (Superconducting Tunnel Junctions). The DROID configuration allows the reconstruction of the position of the photon absorption and therefore it can replace a number of single STJ's in a detector array. We present a 2D model which describes the response of DROIDs with partial trapping in the STJs. The model describes diffusion of quasiparticles (qps) and imperfect confinement via exchange of qps between the absorber and STJ. It incorporates possible diffusion mismatch between absorber and STJ, possible asymmetry between the STJs as well as between the base and top electrodes of the STJs, and photon absorption in the absorber or base or top film of the STJ. Dedicated experiments have been conducted to test the different aspects of the model. We find a good agreement between the model and experimental results.

  2. Results of experimental testing of hee girl students’ motor skills at aerobic trainings

    Directory of Open Access Journals (Sweden)

    Martinova N. P.

    2015-10-01

    Full Text Available Purpose: to analyze dynamic of motor skills’ formation in girl students, who practice aerobic by experimental program. Material: in the research 40 girl students participated. Motor skills level was tested with the help of state and additional tests. Results: it was found that for training quickness it is necessary to use rope skipping in mode, corresponding to development of this quality. For training maximal strength it is purposeful to use more complex power exercises in ground part of the complex. Conclusions: implementation of rope skipping means in dance aerobic trainings increases training influence on practically all motor skills. Rope skipping permits to doze and regulate training load. The same under musical accompaniment develop sense of rhythm. In some modes such jumps facilitate training of speed power qualities and power endurance.

  3. Experimental results for oscillatory water flow in 10-ppi metal foam at low-frequencies

    Science.gov (United States)

    Bağcı, Ö.; Arbak, A.; De Paepe, M.; Dukhan, N.

    2016-09-01

    This experimental study presents results and interpretation of oscillatory water flow in open-cell metal foam. The tested foam had 10 pores per inch and a porosity of 88%. At relatively low frequencies, three flow displacements were employed in the experiment. The influence of frequency and displacement on pressure loss and friction factor is discussed. A correlation of friction factor as a function of the kinetic Reynolds number was determined. Porous media parameters, permeability and drag coefficient, were also found for the same foam via steady-state flow experiments in the Darcy and Forchheimer regimes. The friction factor of oscillating flow was found to be higher than that of steady state. The findings of this study are considered important for oscillating heat transfer in metal foam.

  4. Results of experimental tests simulating supply pressure decrease in a K process tube

    Energy Technology Data Exchange (ETDEWEB)

    Toyoda, K.G.; Calkin, J.F.

    1957-11-13

    Simultaneous reduction of coolant to several or all reactor tubes raises concern not only for the adequacy of protection in the individual process tube but also the reactor as a whole. In event of such flow reduction, the heat generation does not decrease until at least 1.4 seconds have elapsed following the accident. Thus, the water temperature from each tube will rise, and result in an increase in the bulk water temperature. If the increase in bulk water temperature is such that saturation temperature at the top of downcomer is reached, pressurization may occur at that point and exceed the maximum recommended working pressure limit (approximately 1 to 2 psig). The purpose of this report is to present experimental data on a series of tests which were made to simulate flow reductions to a K type process tube by simulated front header pressure decreases.

  5. Preliminary Results on the Experimental Investigation of the Structure Functions of Bound Nucleons

    Energy Technology Data Exchange (ETDEWEB)

    Bodek, Arie [University of Rochester, Rochester, NY

    2015-09-01

    We present preliminary results on an experimental study of the nuclear modification of the longitudinal (σL) and transverse (σT) 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= σLT for nuclei (RA) and for deuterium (RD) 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, RA < RD.

  6. An epistemology and expectations survey about experimental physics: Development and initial results

    CERN Document Server

    Zwickl, Benjamin M; Finkelstein, Noah; Lewandowski, H J

    2013-01-01

    In response to national calls to better align physics laboratory courses with the way physicists engage in research, we have developed an epistemology and expectations survey to assess how students perceive the nature of physics experiments in the contexts of laboratory courses and the professional research laboratory. The Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS) evaluates students' shifts in epistemology and affect at the beginning and end of a semester. Also, at the end of the semester, the E-CLASS assesses students' reflections on their course's expectations for earning a good grade. By basing survey statements on widely embraced learning goals and common critiques of teaching labs, the E-CLASS serves as an assessment tool for lab courses across the undergraduate curriculum and as a tool for PER research. We present the development, evidence of validation, and initial formative assessment results from a sample that includes 45 classes at 20 institutions. We also d...

  7. Carbide Type Influence on Tribological Properties of Hard Faced Steel Layer Part II- Experimental Results

    Directory of Open Access Journals (Sweden)

    V. Lazic

    2010-09-01

    Full Text Available In this paper is presented a preceding procedure that should be conducted in order to successfully regenerate damaged forging dies by the hard facing process. After the tool damage types identification, as well as their causes, we have chosen the procedure and the parameters of hard facing that we further corrected by conducting the test hard facings on models. Thus, we were able to relate the experimental results outputs with the repair technology, taking as a criterion the quality of the surface layers wear resistance such as friction coefficient and width of hard faced zone, hardness and its distribution in cross section, then microstructure of characteristic of hard faced zones, etc. This research points out significancy of tribological properties of certain types of carbides and their effects on metal matrix, in which carbides are embedded. Our tribological investigations have shown that the working life of the hard faced tool can be longer than that of the new tool.

  8. Structure of krypton gas: Monte Carlo results, virial expansions, and real experimental data

    Science.gov (United States)

    Egelstaff, P. A.; Teitsma, Albert; Wang, S. S.

    1980-10-01

    We have made Monte Carlo calculations of the pair correlation function g(r) of a dense gas along the 297 K isotherm using a published pair potential for krypton. Eleven states were simulated, and then, using the pair potential plus the Axilrod-Teller triple-dipole potential, seven states were simulated. The effect of the triplet potential was very small except near the principal peak of g(r). We compare, in real and Fourier space, these results to the virial expansion of g(r) at low densities to test its range of validity. This work provided the background for the interpretation of the experimental data of Teitsma and Egelstaff on real krypton gas, and examples are given involving the extraction of the pair- and triplet-potential terms.

  9. Preliminary experimental results on studying possibility of variable mass liner (VML) formation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The main objective of the present experiment was to study the formation process and initial stage of acceleration of a variable-mass plasma liner (VML). The method is based on magnetic acceleration of a liner with the mass reduced during such acceleration. The experiment was carried out on February 16 at VNIIEF. This report describes the results of measurements obtained in the experiment and preliminary analysis of the results characterizing operation of the test facility main units: helical EMG; 5-module disk EMG 400 mm in diameter (DEMG); ponderomotive unit (PU) with a cylindric condensed liner and a special tooth-cutoff. The first part of the report presents measurement results obtained on the VNIIEF`s diagnostic equipment that are compared with those obtained by American specialists on their diagnostic equipment. Information submitted by American specialists is included in part 2 of this report. The second part of the report presents preliminary computational-theoretic analysis of the main measured results describing operation of DEMG TL system in the experiment; experimental data are compared with theoretical ones obtained before and after the experiment. But more emphasis is placed on the data preliminary analysis indicating that in the experiment a variable mass liner is formed (VML or plasma bubble).

  10. Secondary current properties generated by wind-induced water waves in experimental conditions

    Directory of Open Access Journals (Sweden)

    Michio Sanjou

    2014-06-01

    Full Text Available Secondary currents such as the Langmuir circulation are of high interest in natural rivers and the ocean because they have striking impacts on scour, sedimentation, and mass transport. Basic characteristics have been well-studied in straight open-channel flows. However, little is known regarding secondary circulation induced by wind waves. The presented study describes the generation properties of wind waves observed in the laboratory tank. Wind-induced water waves are known to produce large scale circulations. The phenomenon is observed together with high-speed and low-speed streaks, convergence and divergence zones, respectively. Therefore, it is important to determine the hydrodynamic properties of secondary currents for wind-induced water waves within rivers and lakes. In this study, using two high-speed CMOS cameras, stereoscopic particle image velocimetry (PIV measurements were conducted in order to reveal the distribution of all three components of velocity vectors. The experiments allowed us to investigate the three-dimensional turbulent structure under water waves and the generation mechanism of large-scale circulations. Additionally, a third CMOS camera was used to measure the spanwise profile of thefree-surface elevation. The time-series of velocity components and the free-surface were obtained simultaneously. From our experiments, free-surface variations were found to influence the instantaneous velocity distributions of the cross-sectional plane. We also considered thegeneration process by the phase analysis related to gravity waves and compared the contribution of the apparent stress.

  11. New hadronic currents in TAUOLA: for confrontation with the experimental data

    CERN Document Server

    Was, Z

    2012-01-01

    The status of implementation of new hadronic currents into the Monte Carlo system for simulation of tau-lepton production and decay in high-energy accelerator experiments is reviewed. Since the tau-lepton conference in 2010 substantial progress was achieved: (i) For the TAUOLA Monte Carlo generator of tau-lepton decays, automated and simultaneous use of many versions of form factors for the calculation of optional weights for fits was developed and checked to work in the Belle and BaBar software environment. Alternative parameterizations of hadronic currents based on the Resonance Chiral approach are available now. This was achieved for more than 88% of the total tau hadronic width. (ii) the TAUOLA universal interface based on HepMC (the C++ event record) is available. This is the case for C++ users of PHOTOS Monte Carlo for radiative corrections in decays, as well. An algorithm for weighted events to explore spin effects in analysis of hard processes was prepared. (iii) Kernels featuring a complete first-ord...

  12. Pb-16Li/water interaction: Experimental results and preliminary modelling activities

    Energy Technology Data Exchange (ETDEWEB)

    Ciampichetti, Andrea, E-mail: andrea.ciampichetti@enea.it [ENEA C.R. Brasimone, 40032 Camugno (Italy); Ricapito, Italo [Fusion for Energy, 08019 Barcelona (Spain); Forgione, Nicola; Pesetti, Alessio [Università di Pisa, DIMNP, Largo Lucio Lazzarino 2, 56122 Pisa (Italy)

    2013-10-15

    Highlights: • We studied the interaction between pressurised water and liquid Pb16Li. • The free volume is more impacting than the water enthalpy in determining the pressure evolution of the system. • If a large quantity of water is injected in Pb16Li the temperature increase is very high. • The pressure trends computed by the SIMMER code show a quite good agreement with the experimental data. • From the results some recommendations about the WCLL blanket design can be derived. -- Abstract: The Water Cooled Lithium Lead (WCLL) blanket is based on the eutectic liquid alloy Pb16Li as breeder material and neutron multiplier, and pressurised water as coolant. The liquid breeder flows at few mm/s in the blanket module while the pressurised water is circulated inside double-wall tubes. In spite of the adoption of double-wall tubes for the coolant, the probability of a water large leak because of a tube rupture accident cannot be considered negligible. As a consequence, the Pb16Li/water interaction due to a large break in one or more cooling tubes still remains one of the biggest concerns for this blanket concept. This paper reports the results of three experimental tests on Pb16Li/water interaction carried out at ENEA-Brasimone operating the LIFUS 5 facility. Water was injected into the reaction tank, containing Pb16Li at 330 °C, at a pressure of 155 bar with different values of sub-cooling and with different free volumes in the reaction system. In addition, post test analyses with SIMMER III code are presented in order to compare the pressure evolution measured during the experiments with that calculated by the code.

  13. Theory, simulation and experimental results of the acoustic detection of magnetization changes in superparamagnetic iron oxide.

    Science.gov (United States)

    Gleich, Bernhard; Weizenecker, Jürgen; Borgert, Jörn

    2011-06-29

    Magnetic Particle Imaging is a novel method for medical imaging. It can be used to measure the local concentration of a tracer material based on iron oxide nanoparticles. While the resulting images show the distribution of the tracer material in phantoms or anatomic structures of subjects under examination, no information about the tissue is being acquired. To expand Magnetic Particle Imaging into the detection of soft tissue properties, a new method is proposed, which detects acoustic emissions caused by magnetization changes in superparamagnetic iron oxide. Starting from an introduction to the theory of acoustically detected Magnetic Particle Imaging, a comparison to magnetically detected Magnetic Particle Imaging is presented. Furthermore, an experimental setup for the detection of acoustic emissions is described, which consists of the necessary field generating components, i.e. coils and permanent magnets, as well as a calibrated microphone to perform the detection. The estimated detection limit of acoustic Magnetic Particle Imaging is comparable to the detection limit of magnetic resonance imaging for iron oxide nanoparticles, whereas both are inferior to the theoretical detection limit for magnetically detected Magnetic Particle Imaging. Sufficient data was acquired to perform a comparison to the simulated data. The experimental results are in agreement with the simulations. The remaining differences can be well explained. It was possible to demonstrate the detection of acoustic emissions of magnetic tracer materials in Magnetic Particle Imaging. The processing of acoustic emission in addition to the tracer distribution acquired by magnetic detection might allow for the extraction of mechanical tissue parameters. Such parameters, like for example the velocity of sound and the attenuation caused by the tissue, might also be used to support and improve ultrasound imaging. However, the method can also be used to perform imaging on its own.

  14. Theoretical and experimental study of superradiance pulse generation by heavy-current subnanosecond electron bunches moving in periodic slowing down system

    CERN Document Server

    Ginzburg, N S; Novozhilova, Y V; Sergeev, A S; Shpak, V G; Shunailov, S A; Ul'maskulov, M R; Yalandin, M I

    2002-01-01

    One studied both theoretically and experimentally the Cherenkov superradiance at liner motion of an electron bunch through the periodic slowing down system. Simulations in terms of the KARAT code show that peak intensity of microwave pulses is proportional to the square of total number of particles in a bunch. This finding os conformed experimentally. As a results, at 39 GHz frequency one obtained ultrashort pulses of up to 140 MW high intensity and with 30 ps duration. The RADAN 303 high-current subnanosecond accelerator injected electron bunches with up to 2 A current, 0.5-1.5 ns duration and 200-300 keV particle energy was used as a source of electrons. Simulation shows possibility of further intensification of electromagnetic pulses up to 300-400 MW due to optimization of parameters of accelerating voltage pulse

  15. Current Arabian Plate Motion From Campaign GPS Measurements in Saudi Arabia: Preliminary Results

    Science.gov (United States)

    Almuslmani, B.; Teferle, F. N.; Bingley, R. M.; Moore, T.

    2007-12-01

    Current investigations of the motions of the Arabian and its neighboring plates are primarily based on GPS measurements obtained in the surrounding areas of the Arabian plate, with few stations actually located on the Arabian plate itself in the Kingdom of Saudi Arabia. In order to advance the knowledge of the dynamics of the Arabian plate and its intra-plate deformations, the General Directorate of Military Survey (GDMS), through collaboration with the Institute of Engineering Surveying and Space Geodesy (IESSG), densified the GPS network in Saudi Arabia, covering nearly two thirds of the tectonic plate. Since July 2002, a network of 32 GPS stations has been established at locations of the Saudi Arabia geodetic network. At all of these GPS stations a concrete pillar has been used as the monument and the locations have been selected in order to give the broadest distribution of observing sites. During 2005, 27 additional GPS stations in the Hejaz and Asser Mountains, and the Farasan Islands, all in south-western Saudi Arabia, have been established, for which the past and future campaign GPS measurements will provide valuable data for investigations of crustal deformations close to the plate boundaries between the Nubia, Somalian and Arabian plates. In this presentation we will show results in the form of velocity field and plate motion estimates based on data from at least three campaigns occupying the initial 32 GDMS GPS network stations, but also from a number of IGS stations in the region. Our reference frame is aligned to ITRF2005 and uses approximately 40 IGS reference frame stations located on all major tectonic plates, e.g. Nubia and Somalia, surrounding the Arabian plate. Furthermore, we apply absolute satellite and receiver antenna phase center models together with newly available GPS products from a recent global re-processing effort.

  16. Soil structure modeling with different correlation functions: current results and future perspectives

    Science.gov (United States)

    Karsanina, M.; Gerke, K.; Vasilyev, R.; Skvortsova, E.

    2012-04-01

    One of the main factors defining numerous flow phenomena in soils and other porous media, including fluid and solute movements, is pore structure, e.g., pore volume and its connectivity. In recent decades different numerical methods were developed to quantify single and multi-phase flow in such media on microscale. Among most popular ones are: 1) a wide range of finite difference/element/volume solutions of Navier-Stokes equations and its simplifications; 2) lattice-Boltzmann method; 3) pore-network models. Each method has some advantages and weak sides, so that different research teams usually utilize more than one, depending on the study case. Recent progress in X-ray tomography and some other techniques allows precise determination of soil three-dimensional structure, however, a trade-off between resolution and sample size is usually unavoidable. There are situations then only standard two-dimensional information of porous structure is known due to tomography high cost or resolution limitations. But physical modeling on microscale, there most interfacial processes take place requires 3D information. There are three main approaches to reconstruct (using 2D cut(s) or some other limited information/properties) porous media: 1) statistical methods (correlation functions and simulated annealing, multi-point statistics, entropy methods), 2) sequential methods (sphere or other granular packs) and 3) morphological methods. Multi-point statistical method is believed to excel others due to its simplicity with respect to practical applications and better results (in particular pore space connectivity and anisotropy issues). Recently it was shown that cluster function implication significantly improve reconstruction quality, especially in comparison with original Yeong-Torquato technique based on two-point probability and linear functions. Another possible reason for these correlation functions poorer performance is computer power limitations of that time, e.g., high energy

  17. Experimental design, operation, and results of a 4 kW high temperature steam electrolysis experiment

    Science.gov (United States)

    Zhang, Xiaoyu; O'Brien, James E.; Tao, Greg; Zhou, Can; Housley, Gregory K.

    2015-11-01

    High temperature steam electrolysis (HTSE) is a promising technology for large-scale hydrogen production. However, research on HTSE performance above the kW level is limited. This paper presents the results of 4 kW HTSE long-term test completed in a multi-kW test facility recently developed at the Idaho National Laboratory (INL). The 4 kW HTSE unit consisted of two solid oxide electrolysis stacks electrically connected in parallel, each of which included 40 electrode-supported planar cells. A current density of 0.41 A cm-2 was used for the long-term operating at a constant current mode, resulting in a theoretical hydrogen production rate about 23 slpm. A demonstration of 830 h stable operation was achieved with a degradation rate of 3.1% per 1000 h. The paper also includes detailed descriptions of the piping layout, steam generation and delivery system, test fixture, heat recuperation system, hot zone, instrumentation, and operating conditions. This successful demonstration of multi-kW scale HTSE unit will help to advance the technology toward near-term commercialization.

  18. Experimental Results for the Multipath Performance of Galileo Signals Transmitted by GIOVE-A Satellite

    Directory of Open Access Journals (Sweden)

    Andrew Simsky

    2008-01-01

    Full Text Available Analysis of GIOVE-A signals is an important part of the in-orbit validation phase of the Galileo program. GIOVE-A transmits the ranging signals using all the code modulations currently foreseen for the future Galileo and provides a foretaste of their performance in real-life applications. Due to the use of advanced code modulations, the ranging signals of Galileo provide significant improvement of the multipath performance as compared to current GPS. In this paper, we summarize the results of about 1.5 years of observations using the data from four antenna sites. The analysis of the elevation dependence of averaged multipath errors and the multipath time series for static data indicate significant suppression of long-range multipath by the best Galileo codes. The E5AltBOC signal is confirmed to be a multipath suppression champion for all the data sets. According to the results of the observations, the Galileo signals can be classified into 3 groups: high-performance (E5AltBOC, L1A, E6A, medium-performance (E6BC, E5a, E5b and an L1BC signal, which has the lowest performance among Galileo signals, but is still better than GPS-CA. The car tests have demonstrated that for kinematic multipath the intersignal differences are a lot less pronounced. The phase multipath performance is also discussed.

  19. The Results of Experimental Investigation Recycling Meat and Plant Waste in the Periodic Operation Bioreactor

    Directory of Open Access Journals (Sweden)

    Antonas Misevičius

    2011-12-01

    Full Text Available Waste is unwanted materials that are mainly the result of human activities and one of the sources of environmental pollution. An increase in the world’s population causes a growth in the amounts of waste in the modern world. Every year, the increasing quantities of waste are the major problems these days; therefore, calls for taking effective measures to tackle this problem could be effective tools. The article presents the results of experimental studies on using meat waste and their mixes with herbal waste. The conducted experiments observed the concentrations of methane, hydrogen sulphide and oxygen under periodic mesophilic conditions in the bioreactor. Research has shown that the use of herbal supplements with meat waste produces better results than using only meat waste. The digestion of meat wastes points to an average amount of biogas which is 0.5 m3/m3d, that of meat and herbal waste mixture (19:1 – 0.51 m3/m3d, meat and herbal waste mixture (9:1 – 0.56 m3/m3d. The content of biogas methane was 0.074 m3/m3d, 0.083 m3/m3d, 0.101 m3/m3d respectively.Article in Lithuanian

  20. High Contrast Imaging in the Visible: First Experimental Results at the Large Binocular Telescope

    CERN Document Server

    Pedichini, F; Ambrosino, A; Puglisi, A; Pinna, E; Bailey, V; Carbonaro, L; Centrone, M; Christou, J; Esposito, S; Farinato, J; Fiore, F; Giallongo, E; Hill, J M; Hinz, P M; Sabatini, L

    2016-01-01

    In February 2014, the SHARK-VIS (System for High contrast And coronography from R to K at VISual bands) Forerunner, a high contrast experimental imager operating at visible wavelengths, was installed at LBT (Large Binocular Telescope). Here we report on the first results obtained by recent on-sky tests. These results show the extremely good performance of the LBT ExAO (Extreme Adaptive Optics) system at visible wavelengths, both in terms of spatial resolution and contrast achieved. Similarly to what was done by (Amara et al. 2012), we used the SHARK-VIS Forerunner data to quantitatively assess the contrast enhancement. This is done by injecting several different synthetic faint objects in the acquired data and applying the ADI (angular differential imaging) technique. A contrast of the order of $5 \\times 10^{-5}$ is obtained at 630 nm for angular separations from the star larger than 100 mas. These results are discussed in light of the future development of SHARK-VIS and compared to those obtained by other hi...

  1. Experimental characterisation of sprays resulting from impacts of liquid-containing projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Hostikka, Simo, E-mail: simo.hostikka@aalto.fi [Aalto University, Espoo (Finland); Silde, Ari; Sikanen, Topi; Vepsä, Ari; Paajanen, Antti [VTT Technical Research Centre of Finland Ltd, Espoo (Finland); Honkanen, Markus [Pixact Oy, Tampere (Finland)

    2015-12-15

    Highlights: • Detailed characterisation of sprays resulting from the impacts of water-filled metal projectiles on a hard wall. • Experimental measurements of spray speed, direction and droplet size. • Detailed analysis of overall spray evolution. • The spray characterisation information can be used in CFD analyses of aircraft impact fires. - Abstract: Modelling and analysing fires following aircraft impacts requires information about the behaviour of liquid fuel. In this study, we investigated sprays resulting from the impacts of water-filled metal projectiles on a hard wall. The weights of the projectiles were in the range of 38–110 kg, with 8.6–68 kg water, and the impact speeds varied between 96 and 169 m/s. The overall spray behaviour was observed with high-speed video cameras. Ultra-high-speed cameras were used in backlight configuration for measuring the droplet size and velocity distributions. The results indicate that the liquid leaves the impact position as a thin sheet of spray in a direction perpendicular to the projectile velocity. The initial spray speeds were 1.5–2.5 times the impact speed, and the Sauter mean diameters were in the 147–344 μm range. This data can be used as boundary conditions in CFD fire analyses, considering the two-phase fuel flow. The overall spray observations, including the spray deceleration rate, can be used for validating the model.

  2. Two-Dimensional Simulation of Electrospun Nanofibrous Structures: Connection of Experimental and Simulated Results

    Directory of Open Access Journals (Sweden)

    Panu Danwanichakul

    2014-01-01

    Full Text Available Nanofibrous mats were obtained from electrospinning Nylon-6 solutions with concentrations of 30 and 35 wt% and were tested for filtration of polystyrene particles in suspension. Some experimental results were compared with the simulated ones. In the simulation, the two-dimensional structures were constructed by randomly depositing a nanofiber, which was assumed as an ellipse with an aspect ratio of 100, one by one. The nanofiber size is assumed to be polydisperse. The results showed that simulated configurations resembled real nanofibers with polydisperse diameters. Fibers from higher solution concentration were larger, resulting in larger pore size, which was confirmed with simulations. Varying the size distribution around the same average value did not make any difference to the surface coverage but it affected 2D pore areas for the systems at low fiber density. In addition, the probability for a particle to pass through the porous structure was less when the fiber density was higher and the particle diameter was larger, which was consistent with the filtration test. Lastly, water flux measurement could yield the void volume fraction as well as the volume-averaged pore diameter, which was found to be greater than the averaged 2D pore diameter from SEM micrographs by the quantity related to the fiber size.

  3. Comparison Between Numerical and Experimental Results on Mechanical Stirrer and Bubbling in a Cylindrical Tank - 13047

    Energy Technology Data Exchange (ETDEWEB)

    Lima da Silva, M.; Sauvage, E.; Brun, P. [CEA-Marcoule, BP 17171, 30207 Bagnols sur Ceze (France); Gagnoud, A.; Fautrelle, Y. [SIMaP, Grenoble INP, UJF, CNRS, BP 75, 38402 Saint Martin D' Heres (France); Riva, R. [CEA-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France)

    2013-07-01

    The process of vitrification in a cold crucible heated by direct induction is used in the fusion of oxides. Its feature is the production of high-purity materials. The high-level of purity of the molten is achieved because this melting technique excludes the contamination of the charge by the crucible. The aim of the present paper is to analyze the hydrodynamic of the vitrification process by direct induction, with the focus in the effects associated with the interaction between the mechanical stirrer and bubbling. Considering the complexity of the analyzed system and the goal of the present work, we simplified the system by not taking into account the thermal and electromagnetic phenomena. Based in the concept of hydraulic similitude, we performed an experimental study and a numerical modeling of the simplified model. The results of these two studies were compared and showed a good agreement. The results presented in this paper in conjunction with the previous work contribute to a better understanding of the hydrodynamics effects resulting from the interaction between the mechanical stirrer and air bubbling in the cold crucible heated by direct induction. Further works will take into account thermal and electromagnetic phenomena in the presence of mechanical stirrer and air bubbling. (authors)

  4. Review of JT-60U experimental results from February to October, 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-02-01

    In 1999, the plasma parameters of reversed shear (RS) plasmas had been extended in (1) DT-equivalent fusion power gain Q{sub DT}{sup eq} - 0.5 (n{sub D}(0){tau}{sub E}T{sub i}(0) - 4x10{sup 20} m{sup -3}{center_dot}keV{center_dot}s) for 0.8 s and (2) full non-inductive current drive with 80% of the bootstrap current fraction. Physics of the internal transport barriers (ITBs) in RS plasmas, including the energy transport and the formation of ITB, were extensively studied. A nearly full current drive (92% non-inductively) was obtained with negative ion based neutral beam (NNB) injection (360 keV, 3.4 MW) in a high {beta}{sub p} H-mode plasma (I{sub p}=1.5 MA, B{sub T}=3.7 T, q{sub 95}=4.2) with high plasma performance ({beta}{sub N}=2.4 and H{sub 89}=2.56). Rise in the central electron temperature (T{sub e} - 9 keV) resulted in the current drive efficiency {eta}{sub CD} of NNB reached 1.3x10{sup 19} A/W/m{sup 2}, the highest for the neutral beam current drive. As for the H-mode plasmas, decrease in the pedestal ion temperature due to strong gas was found cause degradation in core plasma confinement. The operation of an ECRF system of 110 GHz, 0.75 MW (torus injection power) had been started in 1999. Changes in plasma current profiles and suppressions of tearing modes and sawtooth oscillations were observed with ECRF heating. The highest {beta}{sub N} in RS experiments ({beta}{sub N} - 2.8) was obtained in the plasma configuration with a large wall stabilizing effect and resistive wall modes were observed before the disruptions. New real-time feedback control schemes including plasma stored energy, plasma radiation power and so on were used in routine plasma operations. Runaway electron current was terminated when the plasma surface safety factor was forced to drop below 2 or 3. In order to increase pumping efficiency of deuterium and impurity neutrals, the outer pumping slot was opened and the both sides pumping was enabled in the W-shaped divertor in 1999. In the

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

    Science.gov (United States)

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

    1988-01-01

    , and have established conclusively the feasibility and desirability of this approach. We discuss, in summary, recent advances in analog and digital video processing methodology, actuation methods, and bring them to bear on the structural identification problem. We include a brief discussion of our experimental hardware and some recent experimental results which support the practical feasibility of this structural vibration sensing approach.

  6. Dynamics of dual prism adaptation: relating novel experimental results to a minimalistic neural model.

    Directory of Open Access Journals (Sweden)

    Orlando Arévalo

    Full Text Available In everyday life, humans interact with a dynamic environment often requiring rapid adaptation of visual perception and motor control. In particular, new visuo-motor mappings must be learned while old skills have to be kept, such that after adaptation, subjects may be able to quickly change between two different modes of generating movements ('dual-adaptation'. A fundamental question is how the adaptation schedule determines the acquisition speed of new skills. Given a fixed number of movements in two different environments, will dual-adaptation be faster if switches ('phase changes' between the environments occur more frequently? We investigated the dynamics of dual-adaptation under different training schedules in a virtual pointing experiment. Surprisingly, we found that acquisition speed of dual visuo-motor mappings in a pointing task is largely independent of the number of phase changes. Next, we studied the neuronal mechanisms underlying this result and other key phenomena of dual-adaptation by relating model simulations to experimental data. We propose a simple and yet biologically plausible neural model consisting of a spatial mapping from an input layer to a pointing angle which is subjected to a global gain modulation. Adaptation is performed by reinforcement learning on the model parameters. Despite its simplicity, the model provides a unifying account for a broad range of experimental data: It quantitatively reproduced the learning rates in dual-adaptation experiments for both direct effect, i.e. adaptation to prisms, and aftereffect, i.e. behavior after removal of prisms, and their independence on the number of phase changes. Several other phenomena, e.g. initial pointing errors that are far smaller than the induced optical shift, were also captured. Moreover, the underlying mechanisms, a local adaptation of a spatial mapping and a global adaptation of a gain factor, explained asymmetric spatial transfer and generalization of prism

  7. Beryllium metal I. experimental results on acute oral toxicity, local skin and eye effects, and genotoxicity.

    Science.gov (United States)

    Strupp, Christian

    2011-01-01

    The toxicity of soluble metal compounds is often different from that of the parent metal. Since no reliable data on acute toxicity, local effects, and mutagenicity of beryllium metal have ever been generated, beryllium metal powder was tested according to the respective Organisation for Economical Co-Operation and Development (OECD) guidelines. Acute oral toxicity of beryllium metal was investigated in rats and local effects on skin and eye in rabbits. Skin-sensitizing properties were investigated in guinea pigs (maximization method). Basic knowledge about systemic bioavailability is important for the design of genotoxicity tests on poorly soluble substances. Therefore, it was necessary to experimentally compare the capacities of beryllium chloride and beryllium metal to form ions under simulated human lung conditions. Solubility of beryllium metal in artificial lung fluid was low, while solubility in artificial lysosomal fluid was moderate. Beryllium chloride dissolution kinetics were largely different, and thus, metal extracts were used in the in vitro genotoxicity tests. Genotoxicity was investigated in vitro in a bacterial reverse mutagenicity assay, a mammalian cell gene mutation assay, a mammalian cell chromosome aberration assay, and an unscheduled DNA synthesis (UDS) assay. In addition, cell transformation was tested in a Syrian hamster embryo cell assay, and potential inhibition of DNA repair was tested by modification of the UDS assay. Beryllium metal was found not to be mutagenic or clastogenic based on the experimental in vitro results. Furthermore, treatment with beryllium metal extracts did not induce DNA repair synthesis, indicative of no DNA-damaging potential of beryllium metal. A cell-transforming potential and a tendency to inhibit DNA repair when the cell is severely damaged by an external stimulus were observed. Beryllium metal was also found not to be a skin or eye irritant, not to be a skin sensitizer, and not to have relevant acute oral

  8. Some comments on resolution and the analysis and interpretation of experimental results from differential neutron measurements

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.L.

    1979-11-01

    Effects of finite resolution in differential neutron measurements are examined. General procedures for deriving the experimental resolution functions from a knowledge of the experimental parameters are presented. Problems encountered in the comparison of different data sets, when the measured cross section is known to fluctuate with energy, are discussed. The objective is to encourage closer attention to the matter of resolution by experimenters, evaluators and users of neutron nuclear data.

  9. Current treatment for venom-induced consumption coagulopathy resulting from snakebite.

    Directory of Open Access Journals (Sweden)

    Kalana Maduwage

    2014-10-01

    Full Text Available Venomous snakebite is considered the single most important cause of human injury from venomous animals worldwide. Coagulopathy is one of the commonest important systemic clinical syndromes and can be complicated by serious and life-threatening haemorrhage. Venom-induced consumption coagulopathy (VICC is the commonest coagulopathy resulting from snakebite and occurs in envenoming by Viperid snakes, certain elapids, including Australian elapids, and a few Colubrid (rear fang snakes. Procoagulant toxins activate the clotting pathway, causing a broad range of factor deficiencies depending on the particular procoagulant toxin in the snake venom. Diagnosis and monitoring of coagulopathy is problematic, particularly in resource-poor countries where further research is required to develop more reliable, cheap clotting tests. MEDLINE and EMBASE up to September 2013 were searched to identify clinical studies of snake envenoming with VICC. The UniPort database was searched for coagulant snake toxins. Despite preclinical studies demonstrating antivenom binding toxins (efficacy, there was less evidence to support clinical effectiveness of antivenom for VICC. There were no placebo-controlled trials of antivenom for VICC. There were 25 randomised comparative trials of antivenom for VICC, which compared two different antivenoms (ten studies, three different antivenoms (four, two or three different doses or repeat doses of antivenom (five, heparin treatment and antivenom (five, and intravenous immunoglobulin treatment and antivenom (one. There were 13 studies that compared two groups in which there was no randomisation, including studies with historical controls. There have been numerous observational studies of antivenom in VICC but with no comparison group. Most of the controlled trials were small, did not use the same method for assessing coagulopathy, varied the dose of antivenom, and did not provide complete details of the study design (primary outcomes

  10. Design considerations and experimental results for MRI systems using HTS magnets

    Science.gov (United States)

    Parkinson, Ben

    2017-01-01

    An increasing number of magnetic resonance imaging (MRI) systems using high temperature superconductors (HTS) magnets have been designed and constructed, with detailed results of their performance now available. Features of REBCO and BSCCO conductors are described as they pertain to use in high homogeneity magnets, with emphasis placed on the practical use of these conductors in magnets. Methods of coil winding are discussed, in particular the differences between pancake and layer winding techniques. Design considerations for HTS magnets are presented in light of the difficulties presented by quench in these magnets, but also in terms of the features of HTS magnets afforded by their high operating temperatures, namely robust cryogen free operation and the potential to use unshielded gradient coils. Drawing on two example MRI systems, namely a 3 T BSCCO brain imaging magnet developed in Japan and a 1.5 T REBCO orthopaedic imaging system developed in New Zealand, the report details real-world stability and homogeneity of HTS-MRI systems, in particular with regards to the screening current effects observed in these systems. It is concluded that, apart from conductor cost, there are currently no technical obstacles to use of HTS-MRI systems.

  11. Current experimental perspectives on the clinical progression of alcoholic liver disease.

    Science.gov (United States)

    Breitkopf, Katja; Nagy, Laura E; Beier, Juliane I; Mueller, Sebastian; Weng, Honglei; Dooley, Steven

    2009-10-01

    Chronic alcohol abuse is an important cause of morbidity and mortality throughout the world. Liver damage due to chronic alcohol intoxication initially leads to accumulation of lipids within the liver and with ongoing exposure this condition of steatosis may first progress to an inflammatory stage which leads the way for fibrogenesis and finally cirrhosis of the liver. While the earlier stages of the disease are considered reversible, cirrhotic destruction of the liver architecture beyond certain limits causes irreversible damage of the organ and often represents the basis for cancer development. This review will summarize current knowledge about the molecular mechanisms underlying the different stages of alcoholic liver disease (ALD). Recent observations have led to the identification of new molecular mechanisms and mediators of ALD. For example, plasminogen activator inhibitor 1 was shown to play a central role for steatosis, the anti-inflammatory adipokine, adiponectin profoundly regulates liver macrophage function and excessive hepatic deposition of iron is caused by chronic ethanol intoxication and increases the risk of hepatocellular carcinoma development.

  12. Experimental Estimating Deflection of a Simple Beam Bridge Model Using Grating Eddy Current Sensors

    Directory of Open Access Journals (Sweden)

    Hui Zhao

    2012-07-01

    Full Text Available A novel three-point method using a grating eddy current absolute position sensor (GECS for bridge deflection estimation is proposed in this paper. Real spatial positions of the measuring points along the span axis are directly used as relative reference points of each other rather than using any other auxiliary static reference points for measuring devices in a conventional method. Every three adjacent measuring points are defined as a measuring unit and a straight connecting bar with a GECS fixed on the center section of it links the two endpoints. In each measuring unit, the displacement of the mid-measuring point relative to the connecting bar measured by the GECS is defined as the relative deflection. Absolute deflections of each measuring point can be calculated from the relative deflections of all the measuring units directly without any correcting approaches. Principles of the three-point method and displacement measurement of the GECS are introduced in detail. Both static and dynamic experiments have been carried out on a simple beam bridge model, which demonstrate that the three-point deflection estimation method using the GECS is effective and offers a reliable way for bridge deflection estimation, especially for long-term monitoring.

  13. Structural Characterization of Phase Separation in Fe-Cr: A Current Comparison of Experimental Methods

    Science.gov (United States)

    Xu, Xin; Odqvist, Joakim; Colliander, Magnus Hörnqvist; Thuvander, Mattias; Steuwer, Axel; Westraadt, Johan E.; King, Stephen; Hedström, Peter

    2016-12-01

    Self-assembly due to phase separation within a miscibility gap is important in numerous material systems and applications. A system of particular interest is the binary alloy system Fe-Cr, since it is both a suitable model material and the base system for the stainless steel alloy category, suffering from low-temperature embrittlement due to phase separation. Structural characterization of the minute nano-scale concentration fluctuations during early phase separation has for a long time been considered a major challenge within material characterization. However, recent developments present new opportunities in this field. Here, we present an overview of the current capabilities and limitations of different techniques. A set of Fe-Cr alloys were investigated using small-angle neutron scattering (SANS), atom probe tomography, and analytical transmission electron microscopy. The complementarity of the characterization techniques is clear, and combinatorial studies can provide complete quantitative structure information during phase separation in Fe-Cr alloys. Furthermore, we argue that SANS provides a unique in-situ access to the nanostructure, and that direct comparisons between SANS and phase-field modeling, solving the non-linear Cahn Hilliard equation with proper physical input, should be pursued.

  14. Molecular hyperpolarizabilities of push–pull chromophores: A comparison between theoretical and experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Capobianco, A. [Dipartimento di Fisica E.R. Caianiello, Università di Salerno, via ponte don Melillo, I-84084 Fisciano (Italy); Centore, R. [Dipartimento di Chimica P. Corradini, Università di Napoli, via Cintia, I-80126 Napoli (Italy); Noce, C. [Dipartimento di Fisica E.R. Caianiello, Università di Salerno, via ponte don Melillo, I-84084 Fisciano (Italy); Peluso, A., E-mail: apeluso@unisa.it [Dipartimento di Chimica e Biologia, Università di Salerno, via ponte don Melillo, I-84084 Fisciano (Italy)

    2013-01-16

    Highlights: ► Electro-optical determined and MP2/DFT computed NLO properties have been compared. ► Significant dependence of dipole moments of elongated NLO chromophores on conformations has been found. ► A thorough comparison between MP2 and DFT/TD-DFT computational approaches has been carried out. ► The two-state model overestimates hyperpolarizability. - Abstract: Electric dipole moments and static first order hyperpolarizabilities of two push–pull molecules with an extended π electron systems have been evaluated at different computational levels and compared with the results of electro-optical absorption measurements, based on the two state model. Calculations show that: (i) the dipole moments of such elongated systems depend significantly on conformation, a thorough conformational search is necessary for a meaningful comparison between theoretical and experimental results; (ii) DFT methods, in particular CAM-B3LYP and M05-2X, yield dipole moments which compare well with those obtained by post Hartree–Fock methods (MP2) and by EOA measurements; (iii) theoretical first order hyperpolarizabilities are largely underestimated, both by MP2 and DFT methods, possibly because of the failure of two state model used in electro-optical measurements.

  15. BRAKE TEST OF SiCp/A356 BRAKE DISK AND INTERPRETATION OF EXPERIMENTAL RESULTS

    Institute of Scientific and Technical Information of China (English)

    YANG Zhiyong; HAN Jianmin; LI Weijing; WANG Jinhua

    2007-01-01

    Material properties are obvious different between aluminum matrix composites and iron and steel materials. After the brake disk braked at the same speed, the average temperature of the aluminum brake disk is 1.5 times as high as one of iron and steel brake disk, the thermal expansion value of the aluminum brake disk is 2 times as big as one of iron and steel brake disk. Mechanical property of the material decreases with the temperature increasing generally during braking, on the other hand, the big thermal stress in the brake disk happens because the material expansion is constrained. Firstly, the reasons of the thermal stress generation and the fracture failure of brake disks during braking are analyzed qualitatively by virtue of three-bar stress frame and sandwich deformation principles in physic, and then the five constraints which cause the thermal stress are summarized. On the base of the experimental results on the 1:1 emergency brake test, the thermal stress and temperature fields are simulated; The behavior of the fracture failure is interpreted semi-quantitatively by finite element analysis. There is the coincident forecast for the fraction position in term of the two methods. In the end, in the light of the analysis and calculation results, it is the general principles observed by the structure design and assembly of the brake disk that are summarized.

  16. Simulation of energy barrier distributions using real particle parameters and comparison with experimental obtained results

    Energy Technology Data Exchange (ETDEWEB)

    Büttner, M., E-mail: Markus.Buettner@uni-jena.de [Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Helmholtzweg 5, 07743 Jena (Germany); Schiffler, M. [Institut für Geowissenschaften, Friedrich-Schiller-Universität Jena, Burgweg 11, 07749 Jena (Germany); Weber, P.; Seidel, P. [Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Helmholtzweg 5, 07743 Jena (Germany)

    2013-11-15

    Distributions of energy barriers in systems of magnetic nanoparticles have been calculated by means of the path integral method and the results have been compared with distributions previously obtained in our experiments by means of the temperature dependent magnetorelaxation method. The path integral method allowed to obtain energies of the interactions of magnetic moments of nanoparticles with axes of their easy magnetisation as well as energies of mutual interactions of magnetic moments. Calculated distributions of energy barriers have been described satisfactorily by curves of the lognormal distribution. We found an agreement between the theory and the experiment at temperatures above approximately 100 K. The influence of the volume concentration of nanoparticles and agglomeration on the energy barrier distribution has been investigated. - Highlights: • The path integral method of calculation allows to satisfactorily reproduce the quantitative experimental results. • The simulations of the energy barrier distributions reflect the lognormal distribution of the MNP found in real experiments. • Higher particle volume concentration leads to a broadening of the simulated energy barrier distribution. • At low particle concentration there is only anisotropy energy. • In case of agglomeration the energy barrier distribution broadens.

  17. Liquid Flow Field on Evaporator of Wiped Short Path Distillation--Experimental Results and Computer Simulation

    Institute of Scientific and Technical Information of China (English)

    XU Songlin; WANG Junwu; XIANG Aishuang; XU Shimin

    2005-01-01

    Short path distillation (SPD) is a kind of high vacuum distillation method, which is suitable for the separation of high boiling, heat sensitivity and viscidity products.In this paper,through measuring the phase-averaged velocity distributions with a conditional sampling method of the particle imaging velocimetry (PIV), the liquid flow field that affects the heat and mass transfer of evaporating thin-film in an SPD evaporator is investigated.Measured results show that the flow velocities decrease rapidly apart from the wiper at different wiper velocities, the maximum velocity appears before wipers, and the quicker the wiping, the larger the flow velocity. Meanwhile, the evaluation of numerical calculations is carried out.The measured velocity distributions indicate clearly the effect of the wiper both on the flow field along its moving direction and on the vortices behind the wiper.Simulation data show that the performance of liquid flow field on the heating surface not only agrees with the experimental results well,but also can give further more information, such as the distribution of turbulent kinetic energy.In this study,turbulent kinetic energy mainly distributes before wipers and laminar flow appears far away from the wipers.

  18. [Acoustic and optical perceptual disorders in depressive diseases--an overview of results from experimental studies].

    Science.gov (United States)

    Kallert, T W

    1996-01-01

    This literature review concentrates on a disregarded part of depressive disorders' symptomatology (especially concerning present-day classifications of mental disorders) that can be approached with a great number of experimental procedures. From the acoustical field the following findings are demonstrated and discussed: elevated click thresholds in auditory signal detection, changed ear asymmetry in dichotic click detection and differences in dichotic listening asymmetries according to symptomatology. The most important results from the so far investigated optical perceptual disturbances in depressive disorders are: breakdown of perceptual defence in the form of greater access to emotionally unpleasant stimuli referring to the tachistoscopic recognition of neutral/unpleasant words, impairments at near-distance assessments, disturbances in recognition and discrimination of facial emotions-especially concerning the perception of emotional chimeric faces. Interpretational attempts for these acoustical and optical disturbances of perception reach from developmental psychology to biological psychiatry. Changes in hemisphere functions hold the dominating position in this discussion. Up to now it remains open to what extent the reported results correlate with the clinical phenomenology of depressive disorders, of what diagnostic specifity they are and if the can be viewed with sufficient reliability as state marker and indicators for theraopeutical effects.

  19. SSI on the Dynamic Behaviour of a Historical Masonry Building: Experimental versus Numerical Results

    Directory of Open Access Journals (Sweden)

    Francesca Ceroni

    2014-11-01

    Full Text Available A reliable procedure to identify the dynamic behaviour of existing masonry buildings is described in the paper, referring to a representative case study: a historical masonry palace located in Benevento (Italy. Since the building has been equipped with a permanent dynamic monitoring system by the Department of Civil Protection, some of the recorded data, acquired in various operating conditions, have been analysed with basic instruments of the Operational Modal Analysis in order to identify the main eigenfrequencies and vibration modes of the structure. The obtained experimental results have been compared to the numerical outcomes provided by three detailed Finite Element (FE models of the building. The influence of Soil-Structure Interaction (SSI has been also introduced in the FE model by a sub-structure approach where concentrated springs were placed at the base of the building to simulate the effect of soil and foundation on the global dynamic behaviour of the structure. The obtained results evidence that subsoil cannot a priori be disregarded in identifying the dynamic response of the building.

  20. Chronic ischaemic mitral regurgitation. Current treatment results and new mechanism-based surgical approaches

    NARCIS (Netherlands)

    Bouma, Wobbe; van der Horst, Iwan C. C.; Wijdh-den Hamer, Inez J.; Erasmus, Michiel E.; Zijlstra, Felix; Mariani, Massimo A.; Ebels, Tjark

    2010-01-01

    Chronic ischaemic mitral regurgitation (CIMR) remains one of the most complex and unresolved aspects in the management of ischaemic heart disease. This review provides an overview of the present knowledge about the different aspects of CIMR with an emphasis on mechanisms, current surgical treatment