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Sample records for 3c high performance

  1. Test results for the Oasis 3C high performance water-pumping windmill

    Energy Technology Data Exchange (ETDEWEB)

    Eggleston, D.M. [DME Engineering, Midland, TX (United States)

    1997-12-31

    The WINDTech International, L.L.C. Oasis 3C, a 3 m diameter, high-performance water-pumping windmill, was tested at the DME Engineering Wind Test Site just south of Midland, Texas from August through December, 1996. This machine utilizes a 3:1 gearbox with rotating counterweights, similar to a conventional oilfield pumping unit, driven by a multibladed rotor. The rotating counterweight system balances most of the pumping loads and reduces gear loads and starting torque by a factor of at least two and often by a factor of four or more. The torque reduction substantially extends gear and bearing life, and reduces wind speeds required for starting by 30 to 50% or more. The O3C was tested pumping from a quiescent fluid depth of 12.2 m (40 ft) from a 28.3 m (93 ft)-deep well, with additional pumping depth simulated using a pressure regulator valve system. A 9.53 cm (3.75 in.) diameter Harbison-Fischer seal-less single-acting piston pump was used to eliminate pump seal friction as a variable, and standard O3C stroke lengths of 30.5 and 15.2 cm (12 and 6 inches) were used. The regulator spring was set to give a maximum stroke rate of 33 strokes per minute. The water pumped was returned to the well after flowing through a settling tank. The tests were performed in accordance with AWEA WECS testing standards. Instrumentation provided 16 channels of data to accurately measure machine performance, including starting wind speeds, flow rates, O3C azimuth, tail furl angle, wind direction tracking errors, RPM, sucker rod loads, and other variables. The most significant performance data is summarized herein. A mathematical model of machine performance was developed that fairly accurately predicts performance for each of three test conditions. The results verify that the O3C is capable of pumping water at wind speeds from 30% to more than 50% lower than comparable un-counterbalanced units.

  2. Ni3Mo3C as anode catalyst for high-performance microbial fuel cells.

    Science.gov (United States)

    Zeng, Li-Zhen; Zhao, Shao-Fei; Li, Wei-Shan

    2015-03-01

    Ni3Mo3C was prepared by a modified organic colloid method and explored as anode catalyst for high-performance microbial fuel cell (MFC) based on Klebsiella pneumoniae (K. pneumoniae). The prepared sample was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET). The activity of the sample as anode catalyst for MFC based on K. pneumoniae was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and polarization curve measurement. The results show that the adding of nickel in Mo2C increases the BET surface area of Mo2C and improves the electrocatalytic activity of Mo2C towards the oxidation of microbial fermentation products. The power density of MFC with 3 mg cm(-2) Ni3Mo3C anode is far higher than that of the MFC with carbon felt as anode without any catalyst, which is 19 % higher than that of Mo2C anode and produced 62 % as much as that of Pt anode, indicating that Ni3Mo3C is comparative to noble metal platinum as anode electrocatalyst for MFCs by increasing the loading.

  3. α-Fe{sub 2}O{sub 3}@C nanorings as anode materials for high performance lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Le; Li, Zhenzhen; Fu, Wenming; Li, Fagen [Department of Physics, Faculty of Science, Ningbo University, Ningbo (China); Wang, Jun, E-mail: wjnaf@ustc.edu [Department of Physics, Faculty of Science, Ningbo University, Ningbo (China); Wang, Wenzhong [School of Science, Minzu University of China, Beijing 100081 (China)

    2015-10-25

    α-Fe{sub 2}O{sub 3}@C core–shell nanorings are prepared by a facile large-scale two-step route incorporating a hydrothermal method and a carbon coated progress. Its structure and morphology are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, and thermogravimetry. It is found that the as-prepared composite is composed of α-Fe{sub 2}O{sub 3}@C nanorings of about 148 nm in outer diameter, 50 nm in thickness, and 115 nm in length. These α-Fe{sub 2}O{sub 3}@C nanorings are enwrapped with ∼3 nm thick carbon shell. And the electrodes exhibit longer cycle life (815 mAhg{sup −1} after cycling 160 times) at high current rate (1000 mAg{sup −1}) compared with that of bare α-Fe{sub 2}O{sub 3} nanorings (810 mAhg{sup −1} after cycling 30 times). The improved performance of the composite is attributed to the bondage from carbon shell, which can enhance the electronic conductivity and structural stability of α-Fe{sub 2}O{sub 3} nanorings. - Highlights: • α-Fe{sub 2}O{sub 3}@C core–shell nanorings are prepared by a facile two-step route. • The α-Fe{sub 2}O{sub 3}@C nanorings are firstly reported as anode materials for LIBs. • The nanorings show a high capacity of 815 mAhg{sup −1} at 1 Ag{sup -1} after 160 cycles.

  4. Synthesis and electrochemical performance of Ti3C2Tx with hydrothermal process

    Science.gov (United States)

    Wang, Libo; Zhang, Heng; Wang, Bo; Shen, Changjie; Zhang, Chuanxiang; Hu, Qianku; Zhou, Aiguo; Liu, Baozhong

    2016-09-01

    In this study, a simple hydrothermal method has been developed to prepare Ti3C2Tx from Ti3AlC2 as a high-performance electrode material for supercapacitors. This method is environmentally friendly and has a low level of danger. The morphology and structure of the Ti3C2Tx can be controlled by hydrothermal reaction time, temperature and NH4F amounts. The prepared Ti3C2Tx was characterized by X-ray diffraction, field emission scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and Brunauer-Emmet-Teller. The results show that the prepared Ti3C2Tx is terminated by O, OH, and F groups. The electrochemical properties of the Ti3C2Tx sample exhibit specific capacitance up to 141 Fcm-3 in 3 M KOH aqueous electrolyte, and even after 1000 cycles, no significant degradation of the volumetric capacitance was observed. These results indicate that the Ti3C2Tx material prepared by this hydrothermal method can be used in high performance supercapacitors.

  5. The high energy spectrum of 3C 273

    CERN Document Server

    Esposito, V; Jean, P; Tramacere, A; Türler, M; Lähteenmäki, A; Tornikoski, M

    2015-01-01

    Aims. The high energy spectrum of 3C 273 is usually understood in terms of inverse-Compton emission in a relativistic leptonic jet. This model predicts variability patterns and delays that could be tested with simultaneous observations from the radio to the GeV range. Methods. The instruments IBIS, SPI, JEM-X on board INTEGRAL, PCA on board RXTE, and LAT on board Fermi have enough sensitivity to follow the spectral variability of 3C 273 from the keV to the GeV. We looked for correlations between the different energy bands, including radio data at 37 GHz collected at the Mets\\"ahovi Radio Observatory and built quasi-simultaneous multiwavelength spectra in the high energy domain when the source is flaring either in the X-rays or in the {\\gamma} rays. Results. Both temporal and spectral analysis suggest a two-component model to explain the complete high energy spectrum. X-ray emission is likely dominated by a Seyfert-like component while the {\\gamma}-ray emission is dominated by a blazar-like component produced ...

  6. Self-assembled Ti3C2Tx MXene film with high gravimetric capacitance.

    Science.gov (United States)

    Hu, Minmin; Li, Zhaojin; Zhang, Hui; Hu, Tao; Zhang, Chao; Wu, Zhen; Wang, Xiaohui

    2015-09-11

    Binder-free MXene films comprising Ti3C2Tx nanoflakes in a face-to-face fashion, achieved by a simple dropping-mild baking approach, exhibit high gravimetric capacitances up to 499 F g(-1) with excellent cyclability and rate performances. The entire electrode system including Ni-foam and MXene film shows volumetric capacitances in the range of 84-226 F cm(-3) depending on the loadings of MXene as active material.

  7. The effect of high glucose levels on the hypermethylation of protein phosphatase 1 regulatory subunit 3C (PPP1R3C) gene in colorectal cancer

    Indian Academy of Sciences (India)

    Soo Kyung Lee; Ji Wook Moon; Yong Woo Lee; Jung Ok Lee; Su Jin Kim; Nami Kim; Jin Kim; Hyeon Soo Kim; Sun-Hwa Park

    2015-03-01

    DNA methylation is an epigenetic event that occurs frequently in colorectal cancer (CRC). Increased glucose level is a strong risk factor for CRC. Protein phosphatase 1 regulatory subunit 3C (PPP1R3C) modulates glycogen metabolism, particularly glycogen synthesis. The aim of this study was to investigate the effect of high glucose levels on DNA methylation of PPP1R3C in CRC. PPP1R3C was significantly hypermethylated in CRC tissues (76/105, 72.38%, < 0.05) and colon cancer cell lines ( < 0.05). CRC tissues obtained from patients with high glucose levels showed that the methylation of PPP1R3C was lower than in patients who had normal levels of glucose. When DLD-1 cells were cultured under conditions of high glucose, the methylation of PPP1R3C was repressed. The expression of PPP1R3C was inversely related to methylation status. In addition, a promoter luciferase assay showed that the transcriptional activity of PPP1R3C was increased in high glucose culture conditions. The number of cells decreased when PPP1R3C was silenced in DLD-1 cells. These results suggest that PPP1R3C, a novel hypermethylated gene in CRC, may play a critical role in cancer cell growth in association with glucose levels.

  8. Thermodynamic properties of solid face centered cubic Rb3C60 at high temperature and pressure

    Science.gov (United States)

    Yang, W.; Sun, J. X.; Liu, H.; Yan, G. F.

    2014-03-01

    Analytic equation of state and thermodynamic quantities of solid fcc Rb3C60 are derived by using an analytic mean field potential method. For intermolecular forces, the double-exponential potential is utilized. Four potential parameters are determined by fitting experimental compression data of Rb3C60 up to 14 GPa at 296 K. Various physical quantities including isothermals, thermal expansion, isochoric heat capacity, Helmholtz free energy and internal energy are calculated and analyzed. Calculated results are consistent with available experimental data in literature. Furthermore, spinodal temperature for Rb3C60 is found to be 2,860 K. Results verify that analytic mean field potential method is a useful approach to consider the anharmonic effect at high temperatures. Numerous reasonable predictions and the change trend of the properties for Rb3C60 at high temperature and pressure have been given.

  9. Multiwavelength Variability of the Blazars Mrk 421 and 3C 454.3 in the High-State

    CERN Document Server

    Gaur, Haritma; Wiita, Paul J

    2011-01-01

    We report the results of photometric observations of the blazars Mrk 421 and 3C 454.3 designed to search for intraday variability (IDV) and short-term variability (STV). Optical photometric observations were spread over eighteen nights for Mrk 421 and seven nights for 3C 454.3 during our observing run in 2009-2010 at the 1.04 m telescope at ARIES, India. Genuine IDV is found for the source 3C 454.3 but not for Mrk 421. Genuine STV is found for both sources. Mrk 421 was revealed by the MAXI X-ray detector on the International Space Station to be in an exceptionally high flux state in 2010 January - February. We performed a correlation between the X-ray and optical bands to search for time delays and found a weak correlation with higher frequencies leading the lower frequencies by about ten days. The blazar 3C 454.3 was found to be in high flux state in November-December 2009. We performed correlations in optical observations made at three telescopes, along with X-ray data from the MAXI satellite and public rel...

  10. Visible Photoluminescence from Cubic (3C) Silicon Carbide Microdisks Coupled to High Quality Whispering Gallery Modes

    CERN Document Server

    Radulaski, Marina; Müller, Kai; Lagoudakis, Konstantinos G; Zhang, Jingyuan Linda; Buckley, Sonia; Kelaita, Yousif A; Alassaad, Kassem; Ferro, Gabriel; Vučković, Jelena

    2014-01-01

    We present the design, fabrication and characterization of cubic (3C) silicon carbide microdisk resonators with high quality factor modes at visible and near infrared wavelengths (600 - 950 nm). Whispering gallery modes with quality factors as high as 2,300 and corresponding mode volumes V ~ 2 ({\\lambda}/n)^3 are measured using laser scanning confocal microscopy at room temperature. We obtain excellent correspondence between transverse-magnetic (TM) and transverse-electric (TE) polarized resonances simulated using Finite Difference Time Domain (FDTD) method and those observed in experiment. These structures based on ensembles of optically active impurities in 3C-SiC resonators could play an important role in diverse applications of nonlinear and quantum photonics, including low power optical switching and quantum memories.

  11. 3C 286: a bright, compact, stable, and highly polarized calibrator for millimeter-wavelength observations

    CERN Document Server

    Agudo, Ivan; Wiesemeyer, Helmut; Molina, Sol N; Casadio, Carolina; Gomez, Jose L; Emmanoulopoulos, Dimitrios

    2012-01-01

    Context. A number of millimeter and submillimeter facilities with linear polarization observing capabilities have started operating during last years. These facilities, as well as other previous millimeter telescopes and interferometers, require bright and stable linear polarization calibrators to calibrate new instruments and to monitor their instrumental polarization. The current limited number of adequate calibrators implies difficulties in the acquisition of these calibration observations. Aims. Looking for additional linear polarization calibrators in the millimeter spectral range, in mid-2006 we started monitoring 3C 286, a standard and highly stable polarization calibrator for radio observations. Methods. Here we present the 3 and 1mm monitoring observations obtained between September 2006 and October 2011 with the XPOL polarimeter on the IRAM 30m Millimeter Telescope. Results. Our observations show that 3C 286 is a bright source of constant total flux with 3mm flux density S_3mm = (0.90 \\pm 0.02) Jy. ...

  12. Very high energy observations of the BL Lac objects 3C 66A and OJ 287

    CERN Document Server

    Lindner, T; Kildea, J; Ball, J; Bramel, D A; Carson, J; Covault, C E; Driscoll, D; Fortin, P; Gingrich, D M; Jarvis, A; Müller, C; Mukherjee, R; Ong, R A; Ragan, K; Scalzo, R A; Williams, D A; Zweerink, J

    2007-01-01

    Using the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE), we have observed the BL Lac objects 3C 66A and OJ 287. These are members of the class of low-frequency-peaked BL Lac objects (LBLs) and are two of the three LBLs predicted by Costamante and Ghisellini to be potential sources of very high energy (>100 GeV) gamma-ray emission. The third candidate, BL Lacertae, has recently been detected by the MAGIC collaboration. Our observations have not produced detections; we calculate a 99% CL upper limit of flux from 3C 66A of 0.15 Crab flux units and from OJ 287 our limit is 0.52 Crab. These limits assume a Crab-like energy spectrum with an effective energy threshold of 185 GeV.

  13. High Temperature Behavior of Cr3C2-NiCr Coatings in the Actual Coal-Fired Boiler Environment

    Science.gov (United States)

    Bhatia, Rakesh; Sidhu, Hazoor Singh; Sidhu, Buta Singh

    2015-03-01

    Erosion-corrosion is a serious problem observed in steam-powered electricity generation plants, and industrial waste incinerators. In the present study, four compositions of Cr3C2-(Ni-20Cr) alloy coating powder were deposited by high-velocity oxy-fuel spray technique on T-91 boiler tube steel. The cyclic studies were performed in a coal-fired boiler at 1123 K ± 10 K (850 °C ± 10 °C). X-ray diffraction, scanning electron microscopy/energy dispersive X-ray analysis and elemental mapping analysis techniques were used to analyze the corrosion products. All the coatings deposited on T-91 boiler tube steel imparted hot corrosion resistance. The 65 pctCr3C2 -35 pct (Ni-20Cr)-coated T-91 steel sample performed better than all other coated samples in the given environment.

  14. Possible light-induced superconductivity in K3C60 at high temperature.

    Science.gov (United States)

    Mitrano, M; Cantaluppi, A; Nicoletti, D; Kaiser, S; Perucchi, A; Lupi, S; Di Pietro, P; Pontiroli, D; Riccò, M; Clark, S R; Jaksch, D; Cavalleri, A

    2016-02-25

    The non-equilibrium control of emergent phenomena in solids is an important research frontier, encompassing effects such as the optical enhancement of superconductivity. Nonlinear excitation of certain phonons in bilayer copper oxides was recently shown to induce superconducting-like optical properties at temperatures far greater than the superconducting transition temperature, Tc (refs 4-6). This effect was accompanied by the disruption of competing charge-density-wave correlations, which explained some but not all of the experimental results. Here we report a similar phenomenon in a very different compound, K3C60. By exciting metallic K3C60 with mid-infrared optical pulses, we induce a large increase in carrier mobility, accompanied by the opening of a gap in the optical conductivity. These same signatures are observed at equilibrium when cooling metallic K3C60 below Tc (20 kelvin). Although optical techniques alone cannot unequivocally identify non-equilibrium high-temperature superconductivity, we propose this as a possible explanation of our results.

  15. Core–shell structure carbon coated ferric oxide (Fe{sub 2}O{sub 3}@C) nanoparticles for supercapacitors with superior electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Yipeng [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Zhang, Haiyan [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Chen, Yiming, E-mail: chenym@gdut.edu.cn [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Deng, Peng; Huang, Zhikun [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Liu, Liying; Qian, Yannan; Li, Yunyong [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Li, Qingyu [School of Chemistry and Chemistry Engineering, Guangxi Normal University, Guilin 541004 (China)

    2015-08-05

    Highlights: • Fe{sub 2}O{sub 3}@C was prepared by using arc discharge method followed by heat treatment. • KOH activation made the core–shell structure Fe{sub 2}O{sub 3}@C porous. • The activated-Fe{sub 2}O{sub 3}@C supercapacitor exhibited superior electrochemical performance. - Abstract: Core–shell structure carbon coated ferric oxide nanoparticles (Fe{sub 2}O{sub 3}@C) were fabricated by the oxidation of carbon coated iron nanoparticles (Fe@C) prepared by a direct current carbon arc discharge method. Porous activated-Fe{sub 2}O{sub 3}@C was prepared by KOH activation of Fe{sub 2}O{sub 3}@C at the temperature of 750 °C. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to characterize the structure and morphology of the Fe{sub 2}O{sub 3}@C and activated-Fe{sub 2}O{sub 3}@C. The specific surface area and pore size distribution of the samples were also tested. The activated-Fe{sub 2}O{sub 3}@C electrodes exhibited good electrochemical performance with a maximum specific capacitance of 612 F g{sup −1} at the charge/discharge current density of 0.5 A g{sup −1} with 5 M NaOH electrolyte. After 10,000 cycling DC tests at the charge/discharge current density of 4 A g{sup −1}, a high level specific capacitance of 518 F g{sup −1} was obtained (90.6% retention of the initial capacity), suggesting excellent long-term cycling stability.

  16. ON THE REDSHIFT OF THE VERY HIGH ENERGY BLAZAR 3C 66A

    Energy Technology Data Exchange (ETDEWEB)

    Furniss, A.; Williams, D. A. [Santa Cruz Institute of Particle Physics and Department of Physics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Fumagalli, M. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Danforth, C. [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Prochaska, J. X. [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2013-03-20

    As a bright gamma-ray source, 3C 66A is of great interest to the high-energy astrophysics community, having a potential for placing cosmological constraints on models for the extragalactic background light (EBL) and the processes which contribute to this photon field. No firm spectroscopic redshift measurement has been possible for this blazar due to a lack of intrinsic emission and absorption features in optical spectra. We present new far-ultraviolet spectra from the Hubble Space Telescope/Cosmic Origins Spectrograph (HST/COS) of the BL Lac object 3C 66A covering the wavelength range 1132-1800 A. The data show a smooth continuum with intergalactic medium absorption features which can be used to place a firm lower limit on the blazar redshift of z {>=} 0.3347. An upper limit is set by statistically treating the non-detection of additional absorbers beyond z = 0.3347, indicating a redshift of less than 0.41 at 99% confidence and ruling out z {>=} 0.444 at 99.9% confidence. We conclude by showing how the redshift limits derived from the COS spectra remove the potential for this gamma-ray emitting blazar to place an upper limit on the flux of the EBL using high energy data from a flare in 2009 October.

  17. The Hot Corrosion Performance of NiCr-Cr3 C2 Cermet Coating to Boiler Tube

    Institute of Scientific and Technical Information of China (English)

    DINGZhang-xiong; TUGuo-fu

    2004-01-01

    Three kinds of NiCr-Cr3 C2 cermet coatings were designed and deposited by the subsonic velocity flame spraying, and their performances of hot corrosion performance were evaluated in comt)arison with 102G,20G boiler tube steel, FeCrAl, NiCrTi, Ni5OCr and NiCrAIMoFe-Cr3 C2 coatings, which are widely used at present for protection of boiler tubes. Meanwhile, the influence of sealer on the hot corrosion resistance of warious coatings and the mechanisms of coating corrosion were explored.

  18. Multiwavelength Observations of a Dramatic High Energy Flare in the Blazar 3C 279

    CERN Document Server

    Wehrle, A E; Urry, C M; Maraschi, L; Ghisellini, G; Hartman, R C

    1997-01-01

    The blazar 3C 279, one of the brightest identified extragalactic objects in the gamma-ray sky, underwent a flare of a factor 10 amplitude in gamma-rays towards the end of a 3-week pointing by CGRO, in 1996 January-February. The flare peak represents the highest gamma-ray intensity ever recorded for this object. During the high state, extremely rapid gamma-ray variability was seen. Coordinated multifrequency observations were carried out with RXTE, ASCA, ROSAT and IUE and from many ground-based observatories, covering most accessible wavelengths. The well-sampled, simultaneous RXTE light curve shows an outburst of lower amplitude (factor of ~3) well correlated with the gamma-ray flare without any apparent lag. The optical-UV light curves, which are not well sampled during the high energy flare, exhibit more modest variations (factor of ~2) and a lower degree of correlation. The flux at millimetric wavelengths was near an historical maximum during the gamma-ray flare peak, with suggestion of a correlated decay....

  19. The High Energy view of the Broad Line Radio Galaxy 3C 111

    CERN Document Server

    Ballo, L; Reeves, J N; Sambruna, R M; Tombesi, F

    2011-01-01

    We present the analysis of Suzaku and XMM-Newton observations of the broad-line radio galaxy (BLRG) 3C 111. Its high energy emission shows variability, a harder continuum with respect to the radio quiet AGN population, and weak reflection features. Suzaku found the source in a minimum flux level; a comparison with the XMM-Newton data implies an increase of a factor of 2.5 in the 0.5-10 keV flux, in the 6 months separating the two observations. The iron K complex is detected in both datasets, with rather low equivalent width(s). The intensity of the iron K complex does not respond to the change in continuum flux. An ultra-fast, high-ionization outflowing gas is clearly detected in the XIS data; the absorber is most likely unstable. Indeed, during the XMM-Newton observation, which was 6 months after, the absorber was not detected. No clear roll-over in the hard X-ray emission is detected, probably due to the emergence of the jet as a dominant component in the hard X-ray band, as suggested by the detection above...

  20. Unexpected High Brightness Temperature 140 PC from the Core in the Jet of 3C 120

    CERN Document Server

    Roca-Sogorb, Mar; Agudo, Ivan; Marscher, Alan P; Jorstad, Svetlana G

    2009-01-01

    We present 1.7, 5, 15, 22 and 43 GHz polarimetric multi--epoch VLBA observations of the radio galaxy 3C 120. The higher frequency observations reveal a new component, not visible before April 2007, located 80 mas from the core (which corresponds to a deprojected distance of 140 pc), with a brightness temperature about 600 times higher than expected at such distances. This component (hereafter C80) is observed to remain stationary and to undergo small changes in its brightness temperature during more than two years of observations. A combination of jet bending, significant flow acceleration, and a very strong shock --for such large distance from the core-- may explain the unusually high Tb of C80, but it seems very unlikely that this corresponds to the usual shock that emerges from the core and travels downstream to the location of C80. It appears that some other intrinsic process in the jet, capable of providing a local burst in particle and/or magnetic field energy, may be responsible for the enhanced bright...

  1. Influence of oxides on high velocity arc sprayed Fe-Al/Cr3C2 composite coatings

    Institute of Scientific and Technical Information of China (English)

    XU Bin-shi; ZHANG Wei; XU Wei-pu

    2005-01-01

    Fe-Al/Cr3 C2 coatings were sprayed on low steel by high velocity arc spraying(HVAS) technology. The influences of oxides on erosion, corrosion and wear behavior for high velocity arc sprayed Fe-Al/Cr3C2 coatings were studied. The results show that HVAS-sprayed Fe-Al/Cr3 C2 coatings have good erosion, heat corrosion and wear resistance. The erosion resistance improves with the increase of the temperature. On one hand, the ferrous oxides are incompact, so they peel off the surface of the coatings easily during the high temperature erosion. On the other hand, compact Al2O3 films on the surface can protect the coatings.

  2. Erosion-Corrosion Behaviors of High Velocity Arc Sprayed Fe-Al/Cr3C2 Coating

    Institute of Scientific and Technical Information of China (English)

    XU Weipu; XU Binshi; ZHANG Wei; WU Yixiong

    2006-01-01

    Iron aluminide intermetallic coatings were prepared from Fe-Al/Cr3C2 cored wires using High Velocity Arc Spraying (HVAS) technology. Erosion and corrosion properties of HVAS sprayed Fe-Al/Cr3C2 coatings were investigated. Results show that the erosion at impingement angle of 30° is more than that of 90°. The erosion resistance of coatings was enhanced with the increase of temperature. Coatings had a better erosion resistance than substrates. The erosion changed from ductile behaviors to brittle behaviors above 450 ℃. At high temperature, the erosion resistances were superior to those at low temperature and room temperature. Coatings had much higher corrosion properties than substrates. The temperature had a little effect on the corrosion resistance of coatings; The corrosion losing of coatings increased slowly with the increase of corrosion time. The HVAS-sprayed Fe-Al/Cr3C2 coatings exhibited a high bond strength and hardness.

  3. High-Fidelity VLA Imaging of the Radio Structure of 3C273

    CERN Document Server

    Perley, R A

    2016-01-01

    3C273, the nearest bright quasar, comprises a strong nuclear core and a bright, one-sided jet extending ~ 23 arcseconds to the SW. The source has been the subject of imaging campaigns in all wavebands. Extensive observations of this source have been made with the Very Large Array and other telescopes as part of a campaign to understand the jet emission mechanisms. Partial results from the VLA radio campaign have been published, but to date, the complete set of VLA imaging results has not been made available. We have utilized the VLA to determine the radio structure of 3C273 in Stokes I, Q, and U, over the widest possible frequency and resolution range. The VLA observed the source in all four of its configurations, and with all eight of its frequency bands, spanning 73.8 MHz to 43 GHz. The data were taken in a pseudo-spectral line mode to minimize the VLA's correlator errors, and were fully calibrated with subsequent self-calibration techniques to maximise image fidelity. Images in Stokes parameters I, Q, and ...

  4. High-Temperature (1200-1400°C) Dry Oxidation of 3C-SiC on Silicon

    Science.gov (United States)

    Sharma, Y. K.; Li, F.; Jennings, M. R.; Fisher, C. A.; Pérez-Tomás, A.; Thomas, S.; Hamilton, D. P.; Russell, S. A. O.; Mawby, P. A.

    2015-11-01

    In a novel approach, high temperatures (1200-1400°C) were used to oxidize cubic silicon carbide (3C-SiC) grown on silicon substrate. High-temperature oxidation does not significantly affect 3C-SiC doping concentration, 3C-SiC structural composition, or the final morphology of the SiO2 layer, which remains unaffected even at 1400°C (the melting point of silicon is 1414°C). Metal-oxide-semiconductor capacitors (MOS-C) and lateral channel metal-oxide-semiconductor field-effect-transistors (MOSFET) were fabricated by use of the high-temperature oxidation process to study 3C-SiC/SiO2 interfaces. Unlike 4H-SiC MOSFET, there is no extra benefit of increasing the oxidation temperature from 1200°C to 1400°C. All the MOSFET resulted in a maximum field-effect mobility of approximately 70 cm2/V s.

  5. High-energy lithium-ion hybrid supercapacitors composed of hierarchical urchin-like WO3/C anodes and MOF-derived polyhedral hollow carbon cathodes.

    Science.gov (United States)

    Xu, Juan; Li, Yuanyuan; Wang, Lei; Cai, Qifa; Li, Qingwei; Gao, Biao; Zhang, Xuming; Huo, Kaifu; Chu, Paul K

    2016-09-22

    A lithium-ion hybrid supercapacitor (Li-HSC) comprising a Li-ion battery type anode and an electrochemical double layer capacitance (EDLC) type cathode has attracted much interest because it accomplishes a large energy density without compromising the power density. In this work, hierarchical carbon coated WO3 (WO3/C) with a unique mesoporous structure and metal-organic framework derived nitrogen-doped carbon hollow polyhedra (MOF-NC) are prepared and adopted as the anode and the cathode for Li-HSCs. The hierarchical mesoporous WO3/C microspheres assembled by radially oriented WO3/C nanorods along the (001) plane enable effective Li(+) insertion, thus exhibit high capacity, excellent rate performance and a long cycling life due to their high Li(+) conductivity, electronic conductivity and structural robustness. The WO3/C structure shows a reversible specific capacity of 508 mA h g(-1) at a 0.1 C rate (1 C = 696 mA h g(-1)) after 160 discharging-charging cycles with excellent rate capability. The MOF-NC achieved the specific capacity of 269.9 F g(-1) at a current density of 0.2 A g(-1). At a high current density of 6 A g(-1), 92.4% of the initial capacity could be retained after 2000 discharging-charging cycles, suggesting excellent cycle stability. The Li-HSC comprising a WO3/C anode and a MOF-NC cathode boasts a large energy density of 159.97 W h kg(-1) at a power density of 173.6 W kg(-1) and 88.3% of the capacity is retained at a current density of 5 A g(-1) after 3000 charging-discharging cycles, which are better than those previously reported for Li-HSCs. The high energy and power densities of the Li-HSCs of WO3/C//MOF-NC render large potential in energy storage.

  6. Extremely high polarization in 2010 outburst of blazar 3C 454.3

    CERN Document Server

    Sasada, Mahito; Fukazawa, Yasushi; Yasuda, Hajimu; Itoh, Ryosuke; Sakimoto, Kiyoshi; Ikejiri, Yuki; Yoshida, Michitoshi; Kawabata, Koji S; Akitaya, Hiroshi; Ohsugi, Takashi; Yamanaka, Masayuki; Komatsu, Tomoyuki; Miyamoto, Hisashi; Nagae, Osamu; Nakaya, Hidehiko; Tanaka, Hiroyuki; Sato, Shuji; Kino, Masaru

    2014-01-01

    The gamma-ray-detected blazar 3C 454.3 exhibits dramatic flux and polarization variations in the optical and near-infrared bands. In December 2010, the object emitted a very bright outburst. We monitored it for approximately four years (including the 2010 outburst) by optical and near-infrared photopolarimetry. During the 2010 outburst, the object emitted two rapid, redder brightenings, at which the polarization degrees (PDs) in both bands increased significantly and the bands exhibited a frequency-dependent polarization. The observed frequency-dependent polarization leads us to propose that the polarization vector is composed of two vectors. Therefore, we separate the observed polarization vectors into short and long-term components that we attribute to the emissions of the rapid brightenings and the outburst that varied the timescale of days and months, respectively. The estimated PD of the short-term component is greater than the maximum observed PD and is close to the theoretical maximum PD. We constrain ...

  7. Extremely high polarization in the 2010 outburst of blazar 3C 454.3

    Energy Technology Data Exchange (ETDEWEB)

    Sasada, Mahito; Kino, Masaru [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Uemura, Makoto; Yoshida, Michitoshi; Kawabata, Koji S.; Akitaya, Hiroshi [Hiroshima Astrophysical Science Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Fukazawa, Yasushi; Yasuda, Hajimu; Itoh, Ryosuke; Sakimoto, Kiyoshi; Ikejiri, Yuki; Ohsugi, Takashi; Komatsu, Tomoyuki; Miyamoto, Hisashi; Nagae, Osamu; Tanaka, Hiroyuki [Department of Physical Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan); Yamanaka, Masayuki [Kwasan Observatory, Kyoto University, 17-1 Kitakazan-ohmine-cho, Yamashina-ku, Kyoto 607-8471 (Japan); Nakaya, Hidehiko [National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588 (Japan); Sato, Shuji, E-mail: sasada@kusastro.kyoto-u.ac.jp [Department of Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)

    2014-04-01

    The gamma-ray-detected blazar 3C 454.3 exhibits dramatic flux and polarization variations in the optical and near-infrared bands. In 2010 December, the object emitted a very bright outburst. We monitored it for approximately four years (including the 2010 outburst) by optical and near-infrared photopolarimetry. During the 2010 outburst, the object emitted two rapid, redder brightenings, at which the polarization degrees (PDs) in both bands increased significantly and the bands exhibited a frequency-dependent polarization. The observed frequency-dependent polarization leads us to propose that the polarization vector is composed of two vectors. Therefore, we separate the observed polarization vectors into short- and long-term components that we attribute to the emissions of the rapid brightenings and the outburst that varied the timescale of days and months, respectively. The estimated PD of the short-term component is greater than the maximum observed PD and is close to the theoretical maximum PD. We constrain the bulk Lorentz factors and inclination angles between the jet axis and the line of sight from the estimated PDs. In this case, the inclination angle of the emitting region of short-term component from the first rapid brightening should be equal to 90°, because the estimated PD of the short-term component was approximately equal to the theoretical maximum PD. Thus, the Doppler factor at the emitting region of the first rapid brightening should be equal to the bulk Lorentz factor.

  8. High-Temperature Erosion of HVOF Sprayed Cr3C2-NiCr Coating and Mild Steel for Boiler Tubes

    Science.gov (United States)

    Yang, Guan-Jun; Li, Chang-Jiu; Zhang, Shi-Jun; Li, Cheng-Xin

    2008-12-01

    The comparison of the high-temperature erosion behavior of a High-velocity oxyfuel (HVOF) sprayed Cr3C2-NiCr coating with mild steel for circulating fluidized bed boiler tubes was investigated. Results showed that the erosion rate of the mild steel at 800 °C was four times that at 300 °C at an erosion angle of 30°. However, the erosion rate of the HVOF sprayed Cr3C2-NiCr coating was not influenced by the temperature in the range of 300-800 °C. It was found that the erosion resistance of HVOF sprayed Cr3C2-NiCr coating was more than three times higher than that of the mild steel at 700-800 °C. In addition to the ploughing on the coating surface, the cracking along splat interfaces in the coating was clearly observed on the cross-sectional microstructure. The results indicate that the erosion performance of the HVOF sprayed Cr3C2-NiCr coating is controlled by the cohesion between splats and can be further enhanced by improving splat cohesion.

  9. VERITAS Observations of a Very High Energy Gamma-ray Flare from the Blazar 3C 66A

    CERN Document Server

    Acciari, V A; Arlen, T; Beilicke, M; Benbow, W; Böttcher, M; Bradbury, S M; Buckley, J H; Bugaev, V; Butt, Y; Byrum, K; Cannon, A; Celik, O; Cesarini, A; Chow, Y C; Ciupik, L; Cogan, P; Cui, W; Daniel, M K; Dickherber, R; Ergin, T; Falcone, A; Fegan, S J; Finley, J P; Fortin, P; Fortson, L; Furniss, A; Gall, D; Gibbs, K; Gillanders, G H; Godambe, S; Grube, J; Guenette, R; Gyuk, G; Hanna, D; Hays, E; Holder, J; Horan, D; Hui, C M; Humensky, T B; Imran, A; Kaaret, Philip; Karlsson, N; Kertzman, M; Kieda, D; Kildea, J; Konopelko, A; Krawczynski, H; Krennrich, F; Lang, M J; Le Bohec, S; Maier, G; McCann, A; McCutcheon, M; Millis, J; Moriarty, P; Mukherjee, R; Nagai, T; Ong, R A; Otte, A N; Pandel, D; Perkins, J S; Petry, D; Pizlo, F; Pohl, M; Quinn, J; Ragan, K; Reyes, L C; Reynolds, P T; Roache, E; Rose, H J; Schroedter, M; Sembroski, G H; Smith, A W; Steele, D; Swordy, S P; Theiling, M; Toner, J A; Varlotta, A; Vasilev, V V; Wagner, R G; Wakely, S P; Ward, J E; Weekes, T C; Weinstein, A; Williams, D A; Wissel, S; Wood, M; Zitzer, B

    2009-01-01

    The intermediate-frequency peaked BL Lacertae (IBL) object 3C 66A is detected during 2007 - 2008 in VHE (very high energy: E > 100 GeV) gamma-rays with the VERITAS stereoscopic array of imaging atmospheric Cherenkov telescopes. An excess of 1791 events is detected, corresponding to a significance of 21.2 standard deviations (sigma), in these observations (32.8 hours live time). The observed integral flux above 200 GeV is 6% of the Crab Nebula's flux and shows evidence for variability on the time-scale of days. The measured energy spectrum is characterized by a soft power law with photon index Gamma = 4.1 +- 0.4_stat +- 0.6_sys. The radio galaxy 3C 66B is excluded as a possible source of the VHE emission.

  10. Piezoresistive effect in p-type 3C-SiC at high temperatures characterized using Joule heating.

    Science.gov (United States)

    Phan, Hoang-Phuong; Dinh, Toan; Kozeki, Takahiro; Qamar, Afzaal; Namazu, Takahiro; Dimitrijev, Sima; Nguyen, Nam-Trung; Dao, Dzung Viet

    2016-06-28

    Cubic silicon carbide is a promising material for Micro Electro Mechanical Systems (MEMS) applications in harsh environ-ments and bioapplications thanks to its large band gap, chemical inertness, excellent corrosion tolerance and capability of growth on a Si substrate. This paper reports the piezoresistive effect of p-type single crystalline 3C-SiC characterized at high temperatures, using an in situ measurement method. The experimental results show that the highly doped p-type 3C-SiC possesses a relatively stable gauge factor of approximately 25 to 28 at temperatures varying from 300 K to 573 K. The in situ method proposed in this study also demonstrated that, the combination of the piezoresistive and thermoresistive effects can increase the gauge factor of p-type 3C-SiC to approximately 20% at 573 K. The increase in gauge factor based on the combination of these phenomena could enhance the sensitivity of SiC based MEMS mechanical sensors.

  11. Piezoresistive effect in p-type 3C-SiC at high temperatures characterized using Joule heating

    Science.gov (United States)

    Phan, Hoang-Phuong; Dinh, Toan; Kozeki, Takahiro; Qamar, Afzaal; Namazu, Takahiro; Dimitrijev, Sima; Nguyen, Nam-Trung; Dao, Dzung Viet

    2016-06-01

    Cubic silicon carbide is a promising material for Micro Electro Mechanical Systems (MEMS) applications in harsh environ-ments and bioapplications thanks to its large band gap, chemical inertness, excellent corrosion tolerance and capability of growth on a Si substrate. This paper reports the piezoresistive effect of p-type single crystalline 3C-SiC characterized at high temperatures, using an in situ measurement method. The experimental results show that the highly doped p-type 3C-SiC possesses a relatively stable gauge factor of approximately 25 to 28 at temperatures varying from 300 K to 573 K. The in situ method proposed in this study also demonstrated that, the combination of the piezoresistive and thermoresistive effects can increase the gauge factor of p-type 3C-SiC to approximately 20% at 573 K. The increase in gauge factor based on the combination of these phenomena could enhance the sensitivity of SiC based MEMS mechanical sensors.

  12. A search for flaring Very-High-Energy cosmic-ray sources with the L3+C muon spectrometer

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Van den Akker, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Bähr, J; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, G J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, M; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiarusi, T; Chiefari, G; Cifarelli, L; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; De Asmundis, R; Dglon, P; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Ding, L K; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Durán, I; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Faber, G; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, F; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, K; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, H; Grabosch, G; Grimm, O; Groenstege, H; Grünewald, M W; Guida, M; Guo, Y N; Gupta, S K; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Haller, C; Hatzifotiadou, D; Hayashi, Y; He, Z X; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Huo, A X; Ito, N; Jin, B N; Jindal, P; Jing, C L; Jones, L W; de Jong, P; Josa-Mutuberría, M I; Kantserov, V A; Kaur, i; Kawakami, S; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, W; Klimentov, A; König, A C; Kok, E; Korn, A; Kopal, M; Koutsenko, V F; Kräber, M; Kuang, H H; Krämer, R W; Krüger, A; Kuijpers, J; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Lei, Y; Leich, H; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Li, L; Li, Z C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma, W G; Ma, X H; Ma, Y Q; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Meng, X W; Merola, L; Meschini, M; Metzger, W J; Mihul, A; van Mil, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Monteleoni, B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Nahnhauer, R; Naumov, V A; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Parriaud, J F; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, F; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pieri, M; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Qing, C R; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Ravindran, K C; Razis, P; Ren, D; Rescigno, M; Reucroft, S; Rewiersma, P A M; Riemann, S; Riles, K; Roe, B P; Rojkov, A; Romero, L; Rosca, A; Rosemann, C; Rosenbleck, C; Rosier-Lees, S; Roth, S; Rubio, J A; Ruggiero, G; Rykaczewski, H; Saidi, R; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schmitt, V; Schöneich, B; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shen, C Q; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sulanke, H; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, L; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Trowitzsch, G; Tully, C; Tung, K L; Ulbricht, J; Unger, M; Valente, E; Verkooijen, H; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, G; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, R G; Wang, Q; Wang, X L; Wang, X W; Wang, Z M; Weber, M; Van Wijk, R F; Wijnen, T A M; Wilkens, H; Wynhoff, S; Xia, L; Xu, Y P; Xu, J S; Xu, Z Z; Yang, B Z; Yang, C G; Yang, H J

    2006-01-01

    The L3+C muon detector at the Cern electron-position collider, LEP, is used for the detection of very-high-energy cosmic \\gamma-ray sources through the observation of muons of energies above 20, 30, 50 and 100 GeV. Daily or monthly excesses in the rate of single-muon events pointing to some particular direction in the sky are searched for. The periods from mid July to November 1999, and April to November 2000 are considered. Special attention is also given to a selection of known \\gamma-ray sources. No statistically significant excess is observed for any direction or any particular source.

  13. High-pressure phase transition makes B4.3C boron carbide a wide-gap semiconductor

    Science.gov (United States)

    Hushur, Anwar; Manghnani, Murli H.; Werheit, Helmut; Dera, Przemyslaw; Williams, Quentin

    2016-02-01

    Single-crystal B4.3C boron carbide is investigated through the pressure-dependence and inter-relation of atomic distances, optical properties and Raman-active phonons up to ~70 GPa. The anomalous pressure evolution of the gap width to higher energies is striking. This is obtained from observations of transparency, which most rapidly increases around 55 GPa. Full visible optical transparency is approached at pressures of  >60 GPa indicating that the band gap reaches ~3.5 eV at high pressure, boron carbide is a wide-gap semiconductor. The reason is that the high concentration of structural defects controlling the electronic properties of boron carbide at ambient conditions initially decreases and finally vanishes at high pressures. The structural parameters and Raman-active phonons indicate a pressure-dependent phase transition in single-crystal natB4.3C boron carbide near 40 GPa, likely related to structural changes in the C-B-C chains, while the basic icosahedral structure appears to be less affected.

  14. High-pressure phase transition makes B4.3C boron carbide a wide-gap semiconductor.

    Science.gov (United States)

    Hushur, Anwar; Manghnani, Murli H; Werheit, Helmut; Dera, Przemyslaw; Williams, Quentin

    2016-02-01

    Single-crystal B4.3C boron carbide is investigated through the pressure-dependence and inter-relation of atomic distances, optical properties and Raman-active phonons up to ~70 GPa. The anomalous pressure evolution of the gap width to higher energies is striking. This is obtained from observations of transparency, which most rapidly increases around 55 GPa. Full visible optical transparency is approached at pressures of  >60 GPa indicating that the band gap reaches ~3.5 eV; at high pressure, boron carbide is a wide-gap semiconductor. The reason is that the high concentration of structural defects controlling the electronic properties of boron carbide at ambient conditions initially decreases and finally vanishes at high pressures. The structural parameters and Raman-active phonons indicate a pressure-dependent phase transition in single-crystal (nat)B4.3C boron carbide near 40 GPa, likely related to structural changes in the C-B-C chains, while the basic icosahedral structure appears to be less affected.

  15. Performance, Performance System, and High Performance System

    Science.gov (United States)

    Jang, Hwan Young

    2009-01-01

    This article proposes needed transitions in the field of human performance technology. The following three transitions are discussed: transitioning from training to performance, transitioning from performance to performance system, and transitioning from learning organization to high performance system. A proposed framework that comprises…

  16. Novel and scalable solid-state synthesis of a nanocrystalline FeF3/C composite and its excellent electrochemical performance.

    Science.gov (United States)

    Lee, Jangwook; Kang, Byoungwoo

    2016-07-19

    A scalable solid-state reaction is presented to synthesize an FeF3 cathode material by using PTFE as a source of both fluorine and carbon. The method yields nanocrystalline FeF3/C showing excellent electrochemical performance even without any conducting additive. This method can be utilized for engineering MFs' properties and developing other fluorine compounds.

  17. Constructing B and N separately co-doped carbon nanocapsules-wrapped Fe/Fe3C for oxygen reduction reaction with high current density.

    Science.gov (United States)

    Feng, He; Wang, Lei; Zhao, Lu; Tian, Chungui; Yu, Peng; Fu, Honggang

    2016-09-29

    The exploration of low-cost and highly efficient non-platinum electrocatalysts for the oxygen reduction reaction (ORR) is vital for renewable systems. Herein, we report a novel non-platinum electrocatalyst consisting of B and N separately co-doped graphitic carbon encapsulated Fe/Fe3C nanoparticles (BNGFe), which were synthesized from a facile method by adopting melamine, iron nitrate and boric acid as the precursors. In this synthesis, the N atoms in melamine first bond with the iron ions in iron nitrate, which could prevent the formation of BN covalent bonds during the subsequent pyrolysed process, resulting in the formation of effective B and N separately co-doped graphitic carbon encapsulated on the Fe/Fe3C nanoparticles. The synthetic BNGFe catalyst shows outstanding catalytic performance for ORR with an onset potential of 0.98 V (vs. RHE) and a high limiting diffusion current density, which could be comparable to the state-of-the-art commercial Pt/C catalyst in alkaline electrolyte.

  18. The high activity of 3C 454.3 in autumn 2007. Monitoring by the WEBT during the AGILE detection

    CERN Document Server

    Raiteri, C M; Chen, W P; Hsiao, W -S; Kurtanidze, O M; Nilsson, K; Larionov, V M; Gurwell, M A

    2008-01-01

    The quasar-type blazar 3C 454.3 underwent a phase of high activity in summer and autumn 2007, which was intensively monitored in the radio-to-optical bands by the Whole Earth Blazar Telescope (WEBT). The gamma-ray satellite AGILE detected this source first in late July, and then in November-December 2007. In this letter we present the multifrequency data collected by the WEBT and collaborators during the second AGILE observing period, complemented by a few contemporaneous data from UVOT onboard the Swift satellite. The aim is to trace in detail the behaviour of the synchrotron emission from the blazar jet, and to investigate the contribution from the thermal emission component. Optical data from about twenty telescopes have been homogeneously calibrated and carefully assembled to construct an R-band light curve containing about 1340 data points in 42 days. This extremely well-sampled optical light curve allows us to follow the dramatic flux variability of the source in detail. In addition, we show radio-to-UV...

  19. Synthesis and performance of Li3Ve(PO4)3/C composites as cathode materials

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Carbon-coated Li3V2(PO4)3 cathode materials for lithium-ion batteries were prepared by a carbon-thermal reduction (CTR) method using sucrose as carbon source.The Li3V2(PO4)3/C composite cathode materials were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),and electrochemical measurement.The results show that the Li3V2(PO4)3 samples synthesized using sucrose as carbon source have the same monoclinic structure as the Li3V2(PO4)3 sample synthesized using acetylene black as carbon Source.SEM image exhibits that the particle size is about 1 μm together with homogenous distribution.Electrochemical test shows that the initial discharge capacity of Li3V2(PO4)3 powders is 122 mAh·g-1 at the rate of 0.2C,and the capacity retains 111 mAh·g-1 after 50 cycles.

  20. A frogspawn-inspired hierarchical porous NaTi2(PO4)3-C array for high-rate and long-life aqueous rechargeable sodium batteries

    Science.gov (United States)

    Zhao, Baidan; Lin, Bo; Zhang, Sen; Deng, Chao

    2015-11-01

    Hollow micro/nano-arrays have attracted tremendous attention in the field of energy conversion and storage, but such structures usually compromise the volumetric energy density of the electrode materials. Frogspawn consists of a spawn core and a transparent jelly shell organized in a hierarchical porous array, which exhibits superior mechanical strength and high-efficiency oxygen permeability. It can be used as a model for designing a new high-performance electrode material, which has advantages such as a high surface area, fast mass transport and superior durability. Herein, we report a frogspawn-like NaTi2(PO4)3/C array prepared by a facile preform impregnation strategy. The framework is formed by a hollow carbon sphere connected by the NaTi2(PO4)3/C skeleton, and its hollow is filled with the NaTi2(PO4)3 nanospheres. The whole hierarchical porous three-dimensional array copies the structure of a frogspawn. This unique structure not only enables easy electrolyte percolation and fast electron/ion transport, but also enhances the reversible capacity and cycling durability. When it is applied as an anode of the aqueous sodium ion battery, it exhibits favorable high rate capability and superior cycling stability, and retains 89% of the initial capacity after two thousand cycles at 20 C. Moreover, the full cell using the frogspawn-inspired NaTi2(PO4)3-C as the anode and Na0.44MnO2 as the cathode is capable of ultralong cycling up to one thousand cycles at alternate 10 and 60 C, which is among the best of state-of-the-art aqueous sodium ion systems. Therefore, the frogspawn-inspired architecture provides a new strategy to the tailored design of polyanion materials for high-power applications.Hollow micro/nano-arrays have attracted tremendous attention in the field of energy conversion and storage, but such structures usually compromise the volumetric energy density of the electrode materials. Frogspawn consists of a spawn core and a transparent jelly shell organized in

  1. Direct Synthesis of Fe3C-Functionalized Graphene by High Temperature Autoclave Pyrolysis for Oxygen Reduction

    DEFF Research Database (Denmark)

    Hu, Yang; Jensen, Jens Oluf; Zhang, Wei

    2014-01-01

    We present a novel approach to direct fabrication of few-layer graphene sheets with encapsulated Fe3C nanoparticles from pyrolysis of volatile non-graphitic precursors without any substrate. This one-step autoclave approach is facile and potentially scalable for production. Tested as an electroca......We present a novel approach to direct fabrication of few-layer graphene sheets with encapsulated Fe3C nanoparticles from pyrolysis of volatile non-graphitic precursors without any substrate. This one-step autoclave approach is facile and potentially scalable for production. Tested...... as an electrocatalyst, the graphene-based composite exhibited excellent catalytic activity towards the oxygen reduction reaction in alkaline solution with an onset potential of ca. 1.05 V (vs. the reversible hydrogen electrode) and a half-wave potential of 0.83 V, which is comparable to the commercial Pt/C catalyst....

  2. Is there an interaction between BDKRB2 -9/+9 and GNB3 C825T polymorphisms and elite athletic performance?

    Science.gov (United States)

    Eynon, N; Meckel, Y; Alves, A J; Nemet, D; Eliakim, A

    2011-12-01

    The -9 deletion allele in the BDKRB2 -9/+9 polymorphism was associated previously with improved endurance performance. We compared the frequency distribution of the BDKRB2 -9/+9 (rs5810761) polymorphism between athletes (n=155) of sports with different demands (endurance runners; n=74 vs sprinters; n=81) as well as between athletes of different competitive levels (elite level; n=46 vs national level; n=109). These results were compared with those of 240 non-athletic healthy individuals. We also tested the influence of the interaction between the BDKRB2 -9/+9 and the GNB3 C825T (rs5443) genotypes in relation to endurance performance. Genotype distribution and allele frequencies were found to be similar in the endurance athlete, sprinter, and control groups (P=0.83 for genotype distribution and P=0.9 for allele frequencies). Similarly, no statistical differences were found between the subgroups of elite-level endurance athletes and national-level endurance athletes, or between elite-level and national-level sprinters (P>0.09 for all comparisons). There was no interaction between BDKRB2 -9/+9 and GNB3 C825T polymorphisms in relation to endurance performance (P=0.16 for interaction effect). In conclusion, the BDKRB2 +9/-9 polymorphism is not associated with endurance performance, at least among Israeli athletes, and the GNB3TT+BDKRB2 -9/-9 "optimal genotype" is not associated with endurance performance.

  3. Direct synthesis of Fe3 C-functionalized graphene by high temperature autoclave pyrolysis for oxygen reduction.

    Science.gov (United States)

    Hu, Yang; Jensen, Jens Oluf; Zhang, Wei; Huang, Yunjie; Cleemann, Lars N; Xing, Wei; Bjerrum, Niels J; Li, Qingfeng

    2014-08-01

    We present a novel approach to direct fabrication of few-layer graphene sheets with encapsulated Fe3 C nanoparticles from pyrolysis of volatile non-graphitic precursors without any substrate. This one-step autoclave approach is facile and potentially scalable for production. Tested as an electrocatalyst, the graphene-based composite exhibited excellent catalytic activity towards the oxygen reduction reaction in alkaline solution with an onset potential of ca. 1.05 V (vs. the reversible hydrogen electrode) and a half-wave potential of 0.83 V, which is comparable to the commercial Pt/C catalyst.

  4. High performance homes

    DEFF Research Database (Denmark)

    Beim, Anne; Vibæk, Kasper Sánchez

    2014-01-01

    Can prefabrication contribute to the development of high performance homes? To answer this question, this chapter defines high performance in more broadly inclusive terms, acknowledging the technical, architectural, social and economic conditions under which energy consumption and production occur....... Consideration of all these factors is a precondition for a truly integrated practice and as this chapter demonstrates, innovative project delivery methods founded on the manufacturing of prefabricated buildings contribute to the production of high performance homes that are cost effective to construct, energy...

  5. Microstructural investigation of Si-ion-irradiated single crystal 3C-SiC and SA-Tyrannohex SiC fiber-bonded composite at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Chun-Yu [Institute of Nuclear Engineering and Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); Tsai, Shuo-Cheng [Department of Engineering and System Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); Lin, Hua-Tay [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Chen, Fu-Rong [Department of Engineering and System Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); Kai, Ji-Jung, E-mail: ceer0001@gmail.com [Institute of Nuclear Engineering and Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); Department of Engineering and System Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China)

    2013-11-15

    Silicon carbides (SiCs) are considered as one of the promising candidates for structural and core materials used in fusion reactor and high temperature gas-cooled reactor (HTGR) due to its high thermal stability, and good resistance to irradiation and chemical attack. Single crystal 3C-SiC with less intrinsic defects was used to precisely characterize the radiation-induced defects in 3C-SiC. In addition, there are limited discussions related to radiation effect of SA-Tyrannohex fiber-bonded composite at high temperatures. Therefore, in this study, single crystal 3C-SiC thin film and SA-Tyrannohex SiC fiber-bonded composite were irradiated at 1000–1350 °C with 7 MeV Si{sup 3+} ion to simulate the neutron irradiation in reactors. The microstructure of the irradiated SiC was examined by using high resolution transmission electron microscope (HRTEM). In irradiated single crystal 3C-SiC, high resolution images showed that the planar defects were extrinsic stacking faulted loop with changing atomic sequences and intrinsic stacking faulted loop, i.e. vacancy loop. In addition, dislocation loops, voids, and edge dislocations in SA-Tyrannohex SiC fiber-bonded composite after irradiation were investigated. Besides, larger voids (with diameter 10–40 nm) formed in alumina with preferred orientation after irradiation perhaps resulting in degradation of strength of the SA-Tyrannohex SiC fiber-bonded composite.

  6. The acclimation of photosynthesis and respiration to temperature in the C3 -C4 intermediate Salsola divaricata: induction of high respiratory CO2 release under low temperature.

    Science.gov (United States)

    Gandin, Anthony; Koteyeva, Nuria K; Voznesenskaya, Elena V; Edwards, Gerald E; Cousins, Asaph B

    2014-11-01

    Photosynthesis in C(3) -C(4) intermediates reduces carbon loss by photorespiration through refixing photorespired CO(2) within bundle sheath cells. This is beneficial under warm temperatures where rates of photorespiration are high; however, it is unknown how photosynthesis in C(3) -C(4) plants acclimates to growth under cold conditions. Therefore, the cold tolerance of the C(3) -C(4) Salsola divaricata was tested to determine whether it reverts to C(3) photosynthesis when grown under low temperatures. Plants were grown under cold (15/10 °C), moderate (25/18 °C) or hot (35/25 °C) day/night temperatures and analysed to determine how photosynthesis, respiration and C(3) -C(4) features acclimate to these growth conditions. The CO(2) compensation point and net rates of CO(2) assimilation in cold-grown plants changed dramatically when measured in response to temperature. However, this was not due to the loss of C(3) -C(4) intermediacy, but rather to a large increase in mitochondrial respiration supported primarily by the non-phosphorylating alternative oxidative pathway (AOP) and, to a lesser degree, the cytochrome oxidative pathway (COP). The increase in respiration and AOP capacity in cold-grown plants likely protects against reactive oxygen species (ROS) in mitochondria and photodamage in chloroplasts by consuming excess reductant via the alternative mitochondrial respiratory electron transport chain.

  7. High Performance Marine Vessels

    CERN Document Server

    Yun, Liang

    2012-01-01

    High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs. In summary, this book: Focuses on technology at the aero-marine interface Covers the full range of high performance marine vessel concepts Explains the historical development of various HPMVs Discusses ferries, racing and pleasure craft, as well as utility and military missions High Performance Marine Vessels is an ideal book for student...

  8. Effects of phosphorous-doping and high temperature annealing on CVD grown 3C-SiC

    Energy Technology Data Exchange (ETDEWEB)

    Rooyen, I.J. van, E-mail: Isabella.vanrooyen@inl.gov [CSIR, National Laser Centre, PO Box 395, Pretoria 0001 (South Africa); Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa); Fuel Design, PBMR, 1279 Mike Crawford Avenue, Centurion 0046 (South Africa); Neethling, J.H. [Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa); Henry, A.; Janzen, E. [Department of Physics, Chemistry and Biology, Semiconductor Materials, Linkoeping University, Linkoeping 58183 (Sweden); Mokoduwe, S.M. [Fuel Design, PBMR, 1279 Mike Crawford Avenue, Centurion 0046 (South Africa); Janse van Vuuren, A.; Olivier, E. [Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa)

    2012-10-15

    The integrity and property behavior of the SiC layer of the Tri-isotropic (TRISO) coated particle (CP) for high temperature reactors (HTR) are very important as the SiC layer is the main barrier for gaseous and metallic fission product release. This study describes the work done on un-irradiated SiC samples prepared with varying phosphorus levels to simulate the presence of phosphorus due to transmutation. {sup 30}Si transmutes to phosphorous ({sup 31}P) and other transmutation products during irradiation, which may affect the integrity of the SiC layer. The P-doping levels of the SiC samples used in this study cover the range from 1.1 Multiplication-Sign 10{sup 15} to 1.2 Multiplication-Sign 10{sup 19} atom/cm{sup 3} and are therefore relevant to the PBMR operating conditions. Annealing from 1000 Degree-Sign C to 2100 Degree-Sign C was performed to study the possible changes in nanostructures and various properties due to temperature. Characterization results by X-ray diffraction (XRD), secondary ion mass spectrometry (SIMS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM), are reported in this article. As grain boundary diffusion is identified as a possible mechanism by which {sup 110m}Ag, one of the fission activation products, might be released through intact SiC layer, grain size measurements is also included in this study. Temperature is evidently one of the factors/parameters amongst others known to influence the grain size of SiC and therefore it is important to investigate the effect of high temperature annealing on the SiC grain size. The ASTM E112 method as well as electron back scatter diffraction (EBSD) was used to determine the grain size of various commercial SiC samples and the SiC layer in experimental PBMR Coated Particles (CPs) after annealing at temperatures ranging from 1600 Degree-Sign C to 2100 Degree-Sign C. The HRTEM micrograph of the decomposition of Si

  9. High energy variability of 3C 273 during the AGILE multiwavelength campaign of December 2007-January 2008

    Science.gov (United States)

    Pacciani, L.; Donnarumma, I.; Vittorini, V.; D'Ammando, F.; Fiocchi, M. T.; Impiombato, D.; Stratta, G.; Verrecchia, F.; Bulgarelli, A.; Chen, A. W.; Giuliani, A.; Longo, F.; Pucella, G.; Vercellone, S.; Tavani, M.; Argan, A.; Barbiellini, G.; Boffelli, F.; Caraveo, P. A.; Cattaneo, P. W.; Cocco, V.; Costa, E.; Del Monte, E.; Di Cocco, G.; Evangelista, Y.; Feroci, M.; Froysland, T.; Fuschino, F.; Galli, M.; Gianotti, F.; Labanti, C.; Lapshov, I.; Lazzarotto, F.; Lipari, P.; Marisaldi, M.; Mereghetti, S.; Morselli, A.; Pellizzoni, A.; Perotti, F.; Picozza, P.; Prest, M.; Rapisarda, M.; Soffitta, P.; Trifoglio, M.; Tosti, G.; Trois, A.; Vallazza, E.; Zanello, D.; Antonelli, L. A.; Colafrancesco, S.; Cutini, S.; Gasparrini, D.; Giommi, P.; Pittori, C.; Salotti, L.

    2009-01-01

    Context: We report the results of a 3-week multi-wavelength campaign targeting the flat spectrum radio quasar 3C 273 carried out with the AGILE gamma-ray mission, covering the 30 MeV-50 GeV and 18-60 keV, the REM observatory (covering the near-IR and optical), Swift (near-UV/Optical, 0.2-10 keV and 15-50 keV), INTEGRAL (3-200 keV) and Rossi XTE (2-12 keV). This is the first observational campaign including gamma-ray data, after the last EGRET observations, more than 8 years ago. Aims: This campaign has been organized by the AGILE team with the aim of observing, studying and modelling the broad band energy spectrum of the source, and its variability on a week timescale, testing the emission models describing the spectral energy distribution of this source. Methods: Our study was carried out using simultaneous light curves of the source flux from all the involved instruments, in the different energy ranges, to search for correlated variability. Then a time-resolved spectral energy distribution was used for a detailed physical modelling of the emission mechanisms. Results: The source was detected in gamma-rays only in the second week of our campaign, with a flux comparable to the level detected by EGRET in June 1991. We found an indication of a possible anti-correlation between the emission at gamma-rays and at soft and hard X-rays, supported by the complete set of instruments. Instead, optical data do not show short term variability, as expected for this source. Only in two preceding EGRET observations (in 1993 and 1997) 3C 273 showed intra-observation variability in gamma-rays. In the 1997 observation, flux variation in gamma-rays was associated with a synchrotron flare. The energy-density spectrum with almost simultaneous data partially covers the regions of synchrotron emission, the big blue bump, and the inverse-Compton. We adopted a leptonic model to explain the hard X/gamma-ray emissions, although from our analysis hadronic models cannot be ruled out. In the

  10. High performance systems

    Energy Technology Data Exchange (ETDEWEB)

    Vigil, M.B. [comp.

    1995-03-01

    This document provides a written compilation of the presentations and viewgraphs from the 1994 Conference on High Speed Computing given at the High Speed Computing Conference, {open_quotes}High Performance Systems,{close_quotes} held at Gleneden Beach, Oregon, on April 18 through 21, 1994.

  11. 3C DUCT DESIGN METHOD

    Institute of Scientific and Technical Information of China (English)

    Huan-RueiShiu; Feng-ChuOu; Sih-LiChen

    2002-01-01

    A new 3C duct design method is proposed for designing a high quality, energy-efficiency cost-effective air duct system. It not only considers the demand of volume flow rate, but also takes into consideration a number of issues including system pressure balance, noise, vibration, space limitation and total system cost. This new method comprises three major calculation procedures:initial computer-aided design (CAD), computer-aided simulation (CAS) and correction processes (CP). An example is presented in this study to understand the characteristics of 3C method. It shows that 3C duct design method provides a simple computation procedure for an optimum air duct system. It also shortens the design schedule, prevents human calculation errors, and reduces the dependence on designer experience. In addition to apply in a new duct system design, 3C duct design method is also a powerful design tool for the expansion of an existing duct system.

  12. Parsec-Scale Jet Behavior of the Quasar 3C 454.3 during the High Gamma-Ray States in 2009 and 2010

    CERN Document Server

    Jorstad, S G; Joshi, M; MacDonald, N R; Scott, T L; Williamson, K E; Smith, P S; Larionov, V M; Agudo, I; Gurwell, M

    2012-01-01

    We analyze total and polarized intensity images of the quasar 3C 454.3 obtained monthly with the VLBA at 43 GHz within the ongoing Boston U. monitoring program of gamma-ray blazars started in June 2007. The data are supplemented by VLBA observations performed during intense campaigns of 2 week duration when the quasar was observed 3 times per campaign. We find a strong increase of activity in the parsec-scale jet of the quasar during high gamma-ray states in December 2009, April 2010, and November 2010. We detect new superluminal knots, K09 and K10, associated with the autumn 2009 and 2010 outbursts, respectively, and compare their kinematic parameters. We analyze optical polarimetric behavior along with polarization parameters of the parsec-scale jet and outline similarities and differences in polarization properties across wavelengths. The results of the analysis support the conclusions that the optical polarized emission is produced in a region located in the vicinity of the mm-wave core of the jet of the ...

  13. Responsive design high performance

    CERN Document Server

    Els, Dewald

    2015-01-01

    This book is ideal for developers who have experience in developing websites or possess minor knowledge of how responsive websites work. No experience of high-level website development or performance tweaking is required.

  14. High-Temperature Behavior of a High-Velocity Oxy-Fuel Sprayed Cr3C2-NiCr Coating

    Science.gov (United States)

    Kaur, Manpreet; Singh, Harpreet; Prakash, Satya

    2012-08-01

    High-velocity oxy-fuel (HVOF) sprayed coatings have the potential to enhance the high-temperature oxidation, corrosion, and erosion-corrosion resistance of boiler steels. In the current work, 75 pct chromium carbide-25 pct (nickel-20 pct chromium) [Cr3C2-NiCr] coating was deposited on ASTM SA213-T22 boiler steel using the HVOF thermal spray process. High-temperature oxidation, hot corrosion, and erosion-corrosion behavior of the coated and bare steel was evaluated in the air, molten salt [Na2SO4-82 pct Fe2(SO4)3], and actual boiler environments under cyclic conditions. Weight-change measurements were taken at the end of each cycle. Efforts were made to formulate the kinetics of the oxidation, corrosion, and erosion-corrosion. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM)/energy dispersive spectroscopy (EDS) techniques were used to analyze the oxidation products. The coating was found to be intact and spallation free in all the environments of the study in general, whereas the bare steel suffered extensive spallation and a relatively higher rate of degradation. The coating was found to be useful to enhance the high-temperature resistance of the steel in all the three environments in this study.

  15. Intestinal CX3C chemokine receptor 1(high) (CX3CR1(high)) myeloid cells prevent T-cell-dependent colitis.

    Science.gov (United States)

    Kayama, Hisako; Ueda, Yoshiyasu; Sawa, Yukihisa; Jeon, Seong Gyu; Ma, Ji Su; Okumura, Ryu; Kubo, Atsuko; Ishii, Masaru; Okazaki, Taku; Murakami, Masaaki; Yamamoto, Masahiro; Yagita, Hideo; Takeda, Kiyoshi

    2012-03-27

    Adequate activation of CD4(+) T lymphocytes is essential for host defense against invading pathogens; however, exaggerated activity of effector CD4(+) T cells induces tissue damage, leading to inflammatory disorders such as inflammatory bowel diseases. Several unique subsets of intestinal innate immune cells have been identified. However, the direct involvement of innate immune cell subsets in the suppression of T-cell-dependent intestinal inflammation is poorly understood. Here, we report that intestinal CX(3)C chemokine receptor 1(high) (CX(3)CR1(high)) CD11b(+) CD11c(+) cells are responsible for prevention of intestinal inflammation through inhibition of T-cell responses. These cells inhibit CD4(+) T-cell proliferation in a cell contact-dependent manner and prevent T-cell-dependent colitis. The suppressive activity is abrogated in the absence of the IL-10/Stat3 pathway. These cells inhibit T-cell proliferation by two steps. Initially, CX(3)CR1(high) CD11b(+) CD11c(+) cells preferentially interact with T cells through highly expressed intercellular adhesion molecule-1/vascular cell adhesion molecule-1; then, they fail to activate T cells because of defective expression of CD80/CD86. The IL-10/Stat3 pathway mediates the reduction of CD80/CD86 expression. Transfer of wild-type CX(3)CR1(high) CD11b(+) CD11c(+) cells prevents development of colitis in myeloid-specific Stat3-deficient mice. Thus, these cells are regulatory myeloid cells that are responsible for maintaining intestinal homeostasis.

  16. Intestinal CX3C chemokine receptor 1high (CX3CR1high) myeloid cells prevent T-cell-dependent colitis

    Science.gov (United States)

    Kayama, Hisako; Ueda, Yoshiyasu; Sawa, Yukihisa; Jeon, Seong Gyu; Ma, Ji Su; Okumura, Ryu; Kubo, Atsuko; Ishii, Masaru; Okazaki, Taku; Murakami, Masaaki; Yamamoto, Masahiro; Yagita, Hideo; Takeda, Kiyoshi

    2012-01-01

    Adequate activation of CD4+ T lymphocytes is essential for host defense against invading pathogens; however, exaggerated activity of effector CD4+ T cells induces tissue damage, leading to inflammatory disorders such as inflammatory bowel diseases. Several unique subsets of intestinal innate immune cells have been identified. However, the direct involvement of innate immune cell subsets in the suppression of T-cell-dependent intestinal inflammation is poorly understood. Here, we report that intestinal CX3C chemokine receptor 1high (CX3CR1high) CD11b+ CD11c+ cells are responsible for prevention of intestinal inflammation through inhibition of T-cell responses. These cells inhibit CD4+ T-cell proliferation in a cell contact-dependent manner and prevent T-cell-dependent colitis. The suppressive activity is abrogated in the absence of the IL-10/Stat3 pathway. These cells inhibit T-cell proliferation by two steps. Initially, CX3CR1high CD11b+ CD11c+ cells preferentially interact with T cells through highly expressed intercellular adhesion molecule-1/vascular cell adhesion molecule-1; then, they fail to activate T cells because of defective expression of CD80/CD86. The IL-10/Stat3 pathway mediates the reduction of CD80/CD86 expression. Transfer of wild-type CX3CR1high CD11b+ CD11c+ cells prevents development of colitis in myeloid-specific Stat3-deficient mice. Thus, these cells are regulatory myeloid cells that are responsible for maintaining intestinal homeostasis. PMID:22403066

  17. Clojure high performance programming

    CERN Document Server

    Kumar, Shantanu

    2013-01-01

    This is a short, practical guide that will teach you everything you need to know to start writing high performance Clojure code.This book is ideal for intermediate Clojure developers who are looking to get a good grip on how to achieve optimum performance. You should already have some experience with Clojure and it would help if you already know a little bit of Java. Knowledge of performance analysis and engineering is not required. For hands-on practice, you should have access to Clojure REPL with Leiningen.

  18. High Performance Concrete

    OpenAIRE

    Traian Oneţ

    2009-01-01

    The paper presents the last studies and researches accomplished in Cluj-Napoca related to high performance concrete, high strength concrete and self compacting concrete. The purpose of this paper is to raid upon the advantages and inconveniences when a particular concrete type is used. Two concrete recipes are presented, namely for the concrete used in rigid pavement for roads and another one for self-compacting concrete.

  19. High-Temperature Exposure Studies of HVOF-Sprayed Cr3C2-25(NiCr)/(WC-Co) Coating

    Science.gov (United States)

    Singh, Harpreet; Kaur, Manpreet; Prakash, Satya

    2016-08-01

    In this research, development of Cr3C2-25(NiCr) + 25%(WC-Co) composite coating was done and investigated. Cr3C2-25(NiCr) + 25%(WC-Co) composite powder [designated as HP2 powder] was prepared by mechanical mixing of [75Cr3C2-25(NiCr)] and [88WC-12Co] powders in the ratio of 75:25 by weight. The blended powders were used as feedstock to deposit composite coating on ASTM SA213-T22 substrate using High Velocity Oxy-Fuel (HVOF) spray process. High-temperature oxidation/corrosion behavior of the bare and coated boiler steels was investigated at 700 °C for 50 cycles in air, as well as, in Na2SO4-82%Fe2(SO4)3 molten salt environment in the laboratory. Erosion-corrosion behavior was investigated in the actual boiler environment at 700 ± 10 °C under cyclic conditions for 1500 h. The weight-change technique was used to establish the kinetics of oxidation/corrosion/erosion-corrosion. X-ray diffraction, field emission-scanning electron microscopy/energy-dispersive spectroscopy (FE-SEM/EDS), and EDS elemental mapping techniques were used to analyze the exposed samples. The uncoated boiler steel suffered from a catastrophic degradation in the form of intense spalling of the scale in all the environments. The oxidation/corrosion/erosion-corrosion resistance of the HVOF-sprayed HP2 coating was found to be better in comparison with standalone Cr3C2-25(NiCr) coating. A simultaneous formation of protective phases might have contributed the best properties to the coating.

  20. Danish High Performance Concretes

    DEFF Research Database (Denmark)

    Nielsen, M. P.; Christoffersen, J.; Frederiksen, J.

    1994-01-01

    In this paper the main results obtained in the research program High Performance Concretes in the 90's are presented. This program was financed by the Danish government and was carried out in cooperation between The Technical University of Denmark, several private companies, and Aalborg University...

  1. High performance AC drives

    CERN Document Server

    Ahmad, Mukhtar

    2010-01-01

    This book presents a comprehensive view of high performance ac drives. It may be considered as both a text book for graduate students and as an up-to-date monograph. It may also be used by R & D professionals involved in the improvement of performance of drives in the industries. The book will also be beneficial to the researchers pursuing work on multiphase drives as well as sensorless and direct torque control of electric drives since up-to date references in these topics are provided. It will also provide few examples of modeling, analysis and control of electric drives using MATLAB/SIMULIN

  2. High Performance FORTRAN

    Science.gov (United States)

    Mehrotra, Piyush

    1994-01-01

    High performance FORTRAN is a set of extensions for FORTRAN 90 designed to allow specification of data parallel algorithms. The programmer annotates the program with distribution directives to specify the desired layout of data. The underlying programming model provides a global name space and a single thread of control. Explicitly parallel constructs allow the expression of fairly controlled forms of parallelism in particular data parallelism. Thus the code is specified in a high level portable manner with no explicit tasking or communication statements. The goal is to allow architecture specific compilers to generate efficient code for a wide variety of architectures including SIMD, MIMD shared and distributed memory machines.

  3. High Performance Liquid Chromatography

    Science.gov (United States)

    Talcott, Stephen

    High performance liquid chromatography (HPLC) has many applications in food chemistry. Food components that have been analyzed with HPLC include organic acids, vitamins, amino acids, sugars, nitrosamines, certain pesticides, metabolites, fatty acids, aflatoxins, pigments, and certain food additives. Unlike gas chromatography, it is not necessary for the compound being analyzed to be volatile. It is necessary, however, for the compounds to have some solubility in the mobile phase. It is important that the solubilized samples for injection be free from all particulate matter, so centrifugation and filtration are common procedures. Also, solid-phase extraction is used commonly in sample preparation to remove interfering compounds from the sample matrix prior to HPLC analysis.

  4. High Performance RAIT

    Institute of Scientific and Technical Information of China (English)

    JamesHughes; CharlesMilligan; 等

    2001-01-01

    The ability to move 10s of TeraBytes in reasonable amounts of time are critical to many of the High Energy Physics applications.This paper examines the issues of high performance,high reliability tape storage systems,and presents the results of a 2-year ASCI Path Forward program to be able to reliably move 1GB/s to an archive that can last 20 years.This paper will cover the requirements.approach,hardware,application software,interface descriptions,performance,measured reliability and predicted reliability.This paper will also touch on future directions for this research.The current research allows systems to sustain 80MB/s of uncompressable data per Fibre Channel interface which is striped out to 8 or more drives.This looks to the application as a single tape drive from both mout and data transfer perspectives .Striping 12 RAIT systems together will provide nearly 1GB/s to tape.The reliability is provided by a method of adding parity tapes to the data stripes.For example,adding 2 parity tapes to an 8-stripe group will allow any 2 of the 10 tapes to be lost or damaged without loss of information.The reliability of RAIT with 8 stripes and 2 parities exceeds that of mirrored tapes while RAIT uses 10 tapes instead of the 16 tapes that a mirror would require.The results of this paper is to be abloe to understand the applicability of RAIT and to be able to understand when it may be useful in High Energy Physics applications.

  5. Application of high-resolution 2D-3C seismic for characterization of the perspective Jurassic shale play in Central Poland

    Science.gov (United States)

    Cyz, M.; Malinowski, M.; Krzywiec, P.; Mulińska, M.; Słonka, Ł.

    2016-10-01

    Here we show the application of broadband (4-120 Hz) 2D-3C seismic for characterization of the perspective Jurassic shale play in Central Poland. Data were acquired along a network of 250 km 2D profiles using single-point, densely spaced receivers (digital 3C sensors) and acquisition was focused on providing both high-resolution and broadband seismic that would enable structural imaging and quantitative interpretation of the key stratigraphic horizons in the Mesozoic sedimentary cover. Such acquisition parameters resulted in good quality data and allowed for more flexibility during processing, e.g., unaliased F-K filtering or digital group forming for ground-roll removal. Processing was oriented to preserve relative amplitudes and the broadband character of the dataset as the input for future quantitative interpretation. We obtained a high-resolution stratigraphic image of the target Upper Jurassic (Upper Kimmeridgian-Tithonian) sequence as well as overall structural portrait of this part of Mid-Polish Trough characterized by strong imprint of the salt tectonics. Lateral continuity of particular stratigraphic sequences has been determined and a more precise structural context for deposition and present-day structure of the Upper Kimmeridgian-Tithonian has been established.

  6. High performance work practices, innovation and performance

    DEFF Research Database (Denmark)

    Jørgensen, Frances; Newton, Cameron; Johnston, Kim

    2013-01-01

    Research spanning nearly 20 years has provided considerable empirical evidence for relationships between High Performance Work Practices (HPWPs) and various measures of performance including increased productivity, improved customer service, and reduced turnover. What stands out from...

  7. Lamb Waves Propagation along 3C-SiC/AlN Membranes for Application in Temperature-Compensated, High-Sensitivity Gravimetric Sensors

    Directory of Open Access Journals (Sweden)

    Cinzia Caliendo

    2013-01-01

    Full Text Available The propagation of the fundamental quasi-symmetric Lamb mode S0 travelling along 3C-SiC/c-AlN composite plates is theoretically studied with respect to the AlN and SiC film thickness, the acoustic wave propagation direction and the electrical boundary conditions. The temperature effects on the phase velocity have been considered for four AlN/SiC-based electroacoustic coupling configurations, specifically addressing the design of temperature-compensated, enhanced-coupling, GHz-range electroacoustic devices. The gravimetric sensitivity and resolution of the four temperature-stable SiC/AlN composite structures are theoretically investigated with respect to both the AlN and SiC sensing surface. The SiC/AlN-based sensor performances are compared to those of surface acoustic waves and Lamb S0 mode mass sensors implemented on bulk conventional piezoelectric materials and on thin suspended membranes.

  8. Lamb Waves Propagation along 3C-SiC/AlN Membranes for Application in Temperature-Compensated, High-Sensitivity Gravimetric Sensors

    Science.gov (United States)

    Caliendo, Cinzia; D'Amico, Arnaldo; Castro, Fabio Lo

    2013-01-01

    The propagation of the fundamental quasi-symmetric Lamb mode S0 travelling along 3C-SiC/c-AlN composite plates is theoretically studied with respect to the AlN and SiC film thickness, the acoustic wave propagation direction and the electrical boundary conditions. The temperature effects on the phase velocity have been considered for four AlN/SiC-based electroacoustic coupling configurations, specifically addressing the design of temperature-compensated, enhanced-coupling, GHz-range electroacoustic devices. The gravimetric sensitivity and resolution of the four temperature-stable SiC/AlN composite structures are theoretically investigated with respect to both the AlN and SiC sensing surface. The SiC/AlN-based sensor performances are compared to those of surface acoustic waves and Lamb S0 mode mass sensors implemented on bulk conventional piezoelectric materials and on thin suspended membranes. PMID:23282585

  9. Lamb waves propagation along 3C-SiC/AlN membranes for application in temperature-compensated, high-sensitivity gravimetric sensors.

    Science.gov (United States)

    Caliendo, Cinzia; D'Amico, Arnaldo; Lo Castro, Fabio

    2013-01-02

    The propagation of the fundamental quasi-symmetric Lamb mode S(0) travelling along 3C-SiC/c-AlN composite plates is theoretically studied with respect to the AlN and SiC film thickness, the acoustic wave propagation direction and the electrical boundary conditions. The temperature effects on the phase velocity have been considered for four AlN/SiC-based electroacoustic coupling configurations, specifically addressing the design of temperature-compensated, enhanced-coupling, GHz-range electroacoustic devices. The gravimetric sensitivity and resolution of the four temperature-stable SiC/AlN composite structures are theoretically investigated with respect to both the AlN and SiC sensing surface. The SiC/AlN-based sensor performances are compared to those of surface acoustic waves and Lamb S(0) mode mass sensors implemented on bulk conventional piezoelectric materials and on thin suspended membranes.

  10. High Performance Work Systems and Firm Performance.

    Science.gov (United States)

    Kling, Jeffrey

    1995-01-01

    A review of 17 studies of high-performance work systems concludes that benefits of employee involvement, skill training, and other high-performance work practices tend to be greater when new methods are adopted as part of a consistent whole. (Author)

  11. High quality epitaxial graphene by hydrogen-etching of 3C-SiC(111) thin-film on Si(111).

    Science.gov (United States)

    Mondelli, Pierluigi; Gupta, Bharati; Betti, Maria Grazia; Mariani, Carlo; Duffin, Josh Lipton; Motta, Nunzio

    2017-03-17

    Etching with atomic hydrogen, as a preparation step before the high-temperature growth process of graphene onto a thin 3C-SiC film grown on Si(111), greatly improves the structural quality of topmost graphene layers. Pit formation and island coalescence, which are typical of graphene growth by SiC graphitization, are quenched and accompanied by widening of the graphene domain sizes to hundreds of nanometers, and by a significant reduction in surface roughness down to a single substrate bilayer. The surface reconstructions expected for graphene and the underlying layer are shown with atomic resolution by scanning tunnelling microscopy. Spectroscopic features typical of graphene are measured by core-level photoemission and Raman spectroscopy.

  12. High quality epitaxial graphene by hydrogen-etching of 3C-SiC(111) thin-film on Si(111)

    Science.gov (United States)

    Mondelli, Pierluigi; Gupta, Bharati; Grazia Betti, Maria; Mariani, Carlo; Lipton Duffin, Josh; Motta, Nunzio

    2017-03-01

    Etching with atomic hydrogen, as a preparation step before the high-temperature growth process of graphene onto a thin 3C-SiC film grown on Si(111), greatly improves the structural quality of topmost graphene layers. Pit formation and island coalescence, which are typical of graphene growth by SiC graphitization, are quenched and accompanied by widening of the graphene domain sizes to hundreds of nanometers, and by a significant reduction in surface roughness down to a single substrate bilayer. The surface reconstructions expected for graphene and the underlying layer are shown with atomic resolution by scanning tunnelling microscopy. Spectroscopic features typical of graphene are measured by core-level photoemission and Raman spectroscopy.

  13. Advanced Reservoir Characterization and Development through High-Resolution 3C3D Seismic and Horizontal Drilling: Eva South Marrow Sand Unit, Texas County, Oklahoma

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler,David M.; Miller, William A.; Wilson, Travis C.

    2002-03-11

    The Eva South Morrow Sand Unit is located in western Texas County, Oklahoma. The field produces from an upper Morrow sandstone, termed the Eva sandstone, deposited in a transgressive valley-fill sequence. The field is defined as a combination structural stratigraphic trap; the reservoir lies in a convex up -dip bend in the valley and is truncated on the west side by the Teepee Creek fault. Although the field has been a successful waterflood since 1993, reservoir heterogeneity and compartmentalization has impeded overall sweep efficiency. A 4.25 square mile high-resolution, three component three-dimensional (3C3D) seismic survey was acquired in order to improve reservoir characterization and pinpoint the optimal location of a new horizontal producing well, the ESU 13-H.

  14. R high performance programming

    CERN Document Server

    Lim, Aloysius

    2015-01-01

    This book is for programmers and developers who want to improve the performance of their R programs by making them run faster with large data sets or who are trying to solve a pesky performance problem.

  15. GHRSST L3C global sub-skin Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on Metop satellites (currently Metop-B) (GDS V2) produced by OSI SAF (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 3 Collated (L3C) dataset derived from the Advanced Very High Resolution Radiometer (AVHRR)...

  16. GHRSST L3C global sub-skin Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on Metop satellites (currently Metop-A) (GDS V2) produced by OSI SAF (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 3 Collated (L3C) dataset derived from the Advanced Very High Resolution Radiometer (AVHRR)...

  17. Powerful Activity in the Bright Ages. I. A Visible/IR Survey of High Redshift 3C Radio Galaxies and Quasars

    CERN Document Server

    Hilbert, Bryan; Kotyla, JohnPaul; Tremblay, Grant R; Stanghellini, Carlo; Sparks, William B; Baum, Stefi A; Capetti, Alessandro; Macchetto, F Duccio; Miley, George K; O'Dea, Christopher P; Perlman, Eric S; Quillen, Alice C

    2016-01-01

    We present new rest frame UV and visible observations of 22 high-redshift (1 < z < 2.5) 3C radio galaxies and QSOs obtained with the Hubble Space Telescope's (HST) Wide Field Camera 3 (WFC3) instrument. Using a custom data reduction strategy in order to assure the removal of cosmic rays, persistence signal, and other data artifacts, we have produced high-quality science-ready images of the targets and their local environments. We observe targets with regions of UV emission suggestive of active star formation. In addition, several targets exhibit highly distorted host galaxy morphologies in the rest frame visible images. Photometric analyses reveals that brighter QSOs tend to be generally redder than their dimmer counterparts. Using emission line fluxes from the literature, we estimate that emission line contamination is relatively small in the rest frame UV images for the QSOs. Using archival VLA data, we have also created radio map overlays for each of our targets, allowing for analysis of the optical ...

  18. Low-frequency study of two giant radio galaxies: 3C 35 and 3C 223

    Science.gov (United States)

    Orrù, E.; Murgia, M.; Feretti, L.; Govoni, F.; Giovannini, G.; Lane, W.; Kassim, N.; Paladino, R.

    2010-06-01

    Aims: Radio galaxies with a projected linear size ⪆1 Mpc are classified as giant radio sources. According to the current interpretation these are old sources which have evolved in a low-density ambient medium. Because radiative losses are negligible at low frequency, extending spectral aging studies in this frequency range will allow us to determine the zero-age electron spectrum injected and then to improve the estimate of the synchrotron age of the source. Methods: We present Very Large Array images at 74 MHz and 327 MHz of two giant radio sources: 3C 35 and 3C 223. We performed a spectral study using 74, 327, 608 and 1400 GHz images. The spectral shape is estimated in different positions along the source. Results: The radio spectrum follows a power-law in the hotspots, while in the inner region of the lobe the shape of the spectrum shows a curvature at high frequencies. This steepening agrees with synchrotron aging of the emitting relativistic electrons. In order to estimate the synchrotron age of the sources, the spectra were fitted with a synchrotron model of emission. They show that 3C 35 is an old source of 143 ± 20 Myr, while 3C 223 is a younger source of 72 ± 4 Myr.

  19. Python high performance programming

    CERN Document Server

    Lanaro, Gabriele

    2013-01-01

    An exciting, easy-to-follow guide illustrating the techniques to boost the performance of Python code, and their applications with plenty of hands-on examples.If you are a programmer who likes the power and simplicity of Python and would like to use this language for performance-critical applications, this book is ideal for you. All that is required is a basic knowledge of the Python programming language. The book will cover basic and advanced topics so will be great for you whether you are a new or a seasoned Python developer.

  20. NGINX high performance

    CERN Document Server

    Sharma, Rahul

    2015-01-01

    System administrators, developers, and engineers looking for ways to achieve maximum performance from NGINX will find this book beneficial. If you are looking for solutions such as how to handle more users from the same system or load your website pages faster, then this is the book for you.

  1. High performance germanium MOSFETs

    Energy Technology Data Exchange (ETDEWEB)

    Saraswat, Krishna [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States)]. E-mail: saraswat@stanford.edu; Chui, Chi On [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States); Krishnamohan, Tejas [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States); Kim, Donghyun [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States); Nayfeh, Ammar [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States); Pethe, Abhijit [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States)

    2006-12-15

    Ge is a very promising material as future channel materials for nanoscale MOSFETs due to its high mobility and thus a higher source injection velocity, which translates into higher drive current and smaller gate delay. However, for Ge to become main-stream, surface passivation and heterogeneous integration of crystalline Ge layers on Si must be achieved. We have demonstrated growth of fully relaxed smooth single crystal Ge layers on Si using a novel multi-step growth and hydrogen anneal process without any graded buffer SiGe layer. Surface passivation of Ge has been achieved with its native oxynitride (GeO {sub x}N {sub y} ) and high-permittivity (high-k) metal oxides of Al, Zr and Hf. High mobility MOSFETs have been demonstrated in bulk Ge with high-k gate dielectrics and metal gates. However, due to their smaller bandgap and higher dielectric constant, most high mobility materials suffer from large band-to-band tunneling (BTBT) leakage currents and worse short channel effects. We present novel, Si and Ge based heterostructure MOSFETs, which can significantly reduce the BTBT leakage currents while retaining high channel mobility, making them suitable for scaling into the sub-15 nm regime. Through full band Monte-Carlo, Poisson-Schrodinger and detailed BTBT simulations we show a dramatic reduction in BTBT and excellent electrostatic control of the channel, while maintaining very high drive currents in these highly scaled heterostructure DGFETs. Heterostructure MOSFETs with varying strained-Ge or SiGe thickness, Si cap thickness and Ge percentage were fabricated on bulk Si and SOI substrates. The ultra-thin ({approx}2 nm) strained-Ge channel heterostructure MOSFETs exhibited >4x mobility enhancements over bulk Si devices and >10x BTBT reduction over surface channel strained SiGe devices.

  2. An energy-conserving, particle dominated, time-dependent model of 3C58 and its observability at high-energies

    CERN Document Server

    Torres, Diego F; Rodriguez, Jonatan Martin

    2012-01-01

    We present a time-dependent spectral model of the nebula 3C58 and compare it with available data. The model is for a leptonic nebula, in which particles are subject to synchrotron, inverse Compton, self-synchrotron Compton, adiabatic, and bremsstrahlung processes. We find that 3C58 is compatible with being a particle dominated nebula, with a magnetic field of 35$\\mu$G. A broken power law injection fits well the multi-frequency data, with a break energy at about 40 GeV. We find that 3C58 is not expected to appear in VERITAS or MAGIC II, unless the local IR background is a factor of \\sim20 off Galactic models averages. For cases in which the CMB dominates the inverse Compton contribution, we find that 3C58 will not be visible either for the Cherenkov Telescope Array.

  3. Effect of Cr/C Ratio on Microstructure and Corrosion Performance of Cr3C2-NiCr Composite Fabricated by Laser Processing

    Science.gov (United States)

    Lou, Deyuan; Liu, Dun; He, Chunlin; Bennett, Peter; Chen, Lie; Yang, Qibiao; Fearon, Eamonn; Dearden, Geoff

    2016-01-01

    The present study focuses on the effect of different Cr/C ratios on the microstructure, microhardness, and corrosion resistance of Ni-based laser clad hardfacings, reinforced by in situ synthesized chromium carbide particles. Cr3C2-NiCr composites have been laser processed with graphite/Cr/Ni powder blends with varying Cr/C ratios. Following phase analysis (x-ray diffraction) and microstructure investigation (scanning electron microscopy; energy dispersive x-ray analysis; transmission electron microscopy), the solidification of laser melt pool is discussed, and the corrosion resistances are examined. Several different zones (planar, dendritic, eutectic and re-melt zone) were formed in these samples, and the thicknesses and shapes of these zones vary with the change of Cr/C ratio. The sizes and types of carbides and the content of reserved graphite in the composites change as the Cr/C ratio varies. With the content of carbides (especially Cr3C2) grows, the microhardness is improved. The corrosive resistance of the composites to 0.2M H2SO4 aqueous solution decreases as the Cr/C ratio reduces owing to not only the decreasing Cr content in the NiCr matrix but also the galvanic corrosion formed within the carbide and graphite containing Ni matrix.

  4. High performance collectors

    Science.gov (United States)

    Ogawa, H.; Hozumi, S.; Mitsumata, T.; Yoshino, K.; Aso, S.; Ebisu, K.

    1983-04-01

    Materials and structures used for flat plate solar collectors and evacuated tubular collectors were examined relative to their overall performance to project effectiveness for building heating and cooling and the feasibility of use for generating industrial process heat. Thermal efficiencies were calculated for black paint single glazed, selective surface single glazed, and selective surface double glazed flat plate collectors. The efficiencies of a single tube and central tube accompanied by two side tube collectors were also studied. Techniques for extending the lifetimes of the collectors were defined. The selective surface collectors proved to have a performance superior to other collectors in terms of the average annual energy delivered. Addition of a black chrome-coated fin system to the evacuated collectors produced significant collection efficiency increases.

  5. High Performance Magnets

    Science.gov (United States)

    2000-03-29

    Our efforts in this project were focused on three different materials, namely; interstitial Sm-Fe carbides and nitrides, high energy product Nd2Fe14B ...magnets with MgO addition, and nanocomposite Nd2Fe14B /alpha-Fe consisting of a fine mixture of hard and soft phases. In the Sm-Fe carbides and

  6. High Performance Biocomputation

    Science.gov (United States)

    2005-03-01

    ab initio calculation of a small protein has been reported (1PNH, a scorpion toxin with 31 residues and 500 atoms; [3]). Hybrid classical and first...challenge can be characterized as highly computationally-savvy and fully capable of effectively exploiting state-of-the-art capability. However, there...enilarrassingly parallel comlrltations, where little or no comnmiinication is required), capacity computing is an effective approac-h. A recent extension of

  7. High performance steam development

    Energy Technology Data Exchange (ETDEWEB)

    Duffy, T.; Schneider, P. [Solar Turbines Inc., San Diego, CA (United States)

    1995-10-01

    Over 30 years ago U.S. industry introduced the world`s highest temperature (1200{degrees}F at 5000 psig) and most efficient power plant, the Eddystone coal-burning steam plant. The highest alloy material used in the plant was 316 stainless steel. Problems during the first few years of operation caused a reduction in operating temperature to 1100{degrees}F which has generally become the highest temperature used in plants around the world. Leadership in high temperature steam has moved to Japan and Europe over the last 30 years.

  8. High performance polymer concrete

    Directory of Open Access Journals (Sweden)

    Frías, M.

    2007-06-01

    Full Text Available This paper studies the performance of concrete whose chief components are natural aggregate and an organic binder —a thermosetting polyester resin— denominated polymer concrete or PC. The material was examined macro- and microscopically and its basic physical and mechanical properties were determined using mercury porosimetry, scanning electron microscopy (SEM-EDAX, X-ray diffraction (XRD and strength tests (modulus of elasticity, stress-strain curves and ultimate strengths. According to the results of these experimental studies, the PC exhibited a low density (4.8%, closed pore system and a concomitantly continuous internal microstructure. This would at least partially explain its mechanical out-performance of traditional concrete, with average compressive and flexural strength values of 100 MPa and over 20 MPa, respectively. In the absence of standard criteria, the bending test was found to be a useful supplement to compressive strength tests for establishing PC strength classes.Este trabajo de investigación aborda el estudio de un hormigón de altas prestaciones, formado por áridos naturales y un aglomerante orgánico constituido por una resina termoestable poliéster, denominado hormigón polimérico HP. Se describe el material a nivel microscópico y macroscópico, presentando sus propiedades físicas y mecánicas fundamentales, mediante diferentes técnicas experimentales, tales como: porosimetría de mercurio, microscopía electrónica (SEM-EDAX, difracción de rayos X (DRX y ensayos mecánicos (módulo de elasticidad, curvas tensión- deformación y resistencias últimas. Como consecuencia del estudio experimental llevado a cabo, se ha podido apreciar cómo el HP está formado por porosidad cerrada del 4,8%, proporcionando una elevada continuidad a su microestructura interna, lo que justifica, en parte, la mejora de propiedades mecánicas respecto al hormigón tradicional, con unos valores medios de resistencia a compresión de 100

  9. Tentative Research on 3C-Based TBI Performance Evaluation Index System%基于3C的TBI绩效评价指标体系初探

    Institute of Scientific and Technical Information of China (English)

    李恒光; 齐中英

    2007-01-01

    对TBI绩效评价的研究,应放在对作为TBI母系统的科技中介的绩效评价研究的大框架下来考虑.科技中介绩效评价研究的意义集中体现在对科技中介发展评价指标的研究方面.科技中介绩效评价指标体系的设计依据、设计原则及必含指标,同样适用于TBI的绩效评价.归纳分析我国TBI绩效评价研究的现状可知,存在着研究不深入、绩效指标体系建立不完整等问题.基于"3C"的TBI绩效评价理论体系的提出,能够使现存的问题得以有效的解决.

  10. High Performance Space Pump Project

    Data.gov (United States)

    National Aeronautics and Space Administration — PDT is proposing a High Performance Space Pump based upon an innovative design using several technologies. The design will use a two-stage impeller, high temperature...

  11. Identification of high-risk Listeria monocytogenes serotypes in lineage I (serotype 1/2a, 1/2c, 3a and 3c) using multiplex PCR

    Science.gov (United States)

    Aims: Using molecular subtyping techniques, Listeria monocytogenes is divided into three major phylogenetic lineages, and a multiplex PCR method can differentiate five L. monocytogenes subgroups: 1/2a-3a, 1/2c-3c, 1/2b-3b-7, 4b-4d-4e, and 4a-4c. In the current study, we conducted genome comparison...

  12. High-Performance Data Converters

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    Novel techniques for multi-bit oversampled data conversion are described. State-of-the-art oversampled data converters are analyzed, leading to the conclusion that their performance is limited mainly by low-resolution signal representation. To increase the resolution, high-performance, high...

  13. High Performance Thin Layer Chromatography.

    Science.gov (United States)

    Costanzo, Samuel J.

    1984-01-01

    Clarifies where in the scheme of modern chromatography high performance thin layer chromatography (TLC) fits and why in some situations it is a viable alternative to gas and high performance liquid chromatography. New TLC plates, sample applications, plate development, and instrumental techniques are considered. (JN)

  14. Radio Polarimetry of 3C119, 3C318, and 3C343 at milliarcsecond resolution

    CERN Document Server

    Mantovani, F; Junor, W; Saikia, D J; Salter, C J

    2010-01-01

    We report VLBA polarimetric observations of the CSS sources 3C119, 3C318, and 3C343 at 5 and 8.4 GHz. The CSS source 3C119 has source rest-frame RM values up to ~10200 rad/m**2 in a region which coincides with a change in the direction of the inner jet. This component is located ~325 pc from the core, which is variable and has a peaked radio spectrum. In the case of 3C318, a rest-frame RM of ~3030 rad/m**2 has been estimated for the brightest component which contributes almost all of the polarised emission. Further, two more extended components have been detected, clearly showing "wiggles" in the jet towards the southern side of the source. The CSS source 3C343 contains two peaks of emission and a curved jet embedded in more diffuse emission. It exhibits complex field directions near the emission peaks, which indicate rest-frame RM values in excess of ~6000 rad/m**2. The locations of the cores in 3C318 and 3C343 are not clear. The available data on mas-scale rest-frame RM estimates for CSS sources show that t...

  15. High Performance Networks for High Impact Science

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Mary A.; Bair, Raymond A.

    2003-02-13

    This workshop was the first major activity in developing a strategic plan for high-performance networking in the Office of Science. Held August 13 through 15, 2002, it brought together a selection of end users, especially representing the emerging, high-visibility initiatives, and network visionaries to identify opportunities and begin defining the path forward.

  16. RavenDB high performance

    CERN Document Server

    Ritchie, Brian

    2013-01-01

    RavenDB High Performance is comprehensive yet concise tutorial that developers can use to.This book is for developers & software architects who are designing systems in order to achieve high performance right from the start. A basic understanding of RavenDB is recommended, but not required. While the book focuses on advanced topics, it does not assume that the reader has a great deal of prior knowledge of working with RavenDB.

  17. High-Performance Operating Systems

    DEFF Research Database (Denmark)

    Sharp, Robin

    1999-01-01

    Notes prepared for the DTU course 49421 "High Performance Operating Systems". The notes deal with quantitative and qualitative techniques for use in the design and evaluation of operating systems in computer systems for which performance is an important parameter, such as real-time applications......, communication systems and multimedia systems....

  18. High-Performance Ball Bearing

    Science.gov (United States)

    Bursey, Roger W., Jr.; Haluck, David A.; Olinger, John B.; Owen, Samuel S.; Poole, William E.

    1995-01-01

    High-performance bearing features strong, lightweight, self-lubricating cage with self-lubricating liners in ball apertures. Designed to operate at high speed (tens of thousands of revolutions per minute) in cryogenic environment like liquid-oxygen or liquid-hydrogen turbopump. Includes inner race, outer race, and cage keeping bearing balls equally spaced.

  19. A Two-Dimensional Zirconium Carbide by Selective Etching of Al3C3 from Nanolaminated Zr3Al3C5.

    Science.gov (United States)

    Zhou, Jie; Zha, Xianhu; Chen, Fan Y; Ye, Qun; Eklund, Per; Du, Shiyu; Huang, Qing

    2016-04-11

    The room-temperature synthesis of a new two-dimensional (2D) zirconium-containing carbide, Zr3C2T(z) MXene is presented. In contrast to traditional preparation of MXene, the layered ternary Zr3Al3C5 material instead of MAX phases is used as source under hydrofluoric acid treatment. The structural, mechanical, and electronic properties of the synthesized 2D carbide are investigated, combined with first-principles density functional calculations. A comparative study on the structrual stability of our obtained 2D Zr3C2T(z) and Ti3C2T(z) MXenes at elevated temperatures is performed. The obtained 2D Zr3C2T(z) exhibits relatively better ability to maintain 2D nature and strucural integrity compared to Ti-based Mxene. The difference in structural stability under high temperature condition is explained by a theoretical investigation on binding energy.

  20. High performance scalable image coding

    Institute of Scientific and Technical Information of China (English)

    Gan Tao; He Yanmin; Zhu Weile

    2007-01-01

    A high performance scalable image coding algorithm is proposed. The salient features of this algorithm are the ways to form and locate the significant clusters. Thanks to the list structure, the new coding algorithm achieves fine fractional bit-plane coding with negligible additional complexity. Experiments show that it performs comparably or better than the state-of-the-art coders. Furthermore, the flexible codec supports both quality and resolution scalability, which is very attractive in many network applications.

  1. INL High Performance Building Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Jennifer D. Morton

    2010-02-01

    High performance buildings, also known as sustainable buildings and green buildings, are resource efficient structures that minimize the impact on the environment by using less energy and water, reduce solid waste and pollutants, and limit the depletion of natural resources while also providing a thermally and visually comfortable working environment that increases productivity for building occupants. As Idaho National Laboratory (INL) becomes the nation’s premier nuclear energy research laboratory, the physical infrastructure will be established to help accomplish this mission. This infrastructure, particularly the buildings, should incorporate high performance sustainable design features in order to be environmentally responsible and reflect an image of progressiveness and innovation to the public and prospective employees. Additionally, INL is a large consumer of energy that contributes to both carbon emissions and resource inefficiency. In the current climate of rising energy prices and political pressure for carbon reduction, this guide will help new construction project teams to design facilities that are sustainable and reduce energy costs, thereby reducing carbon emissions. With these concerns in mind, the recommendations described in the INL High Performance Building Strategy (previously called the INL Green Building Strategy) are intended to form the INL foundation for high performance building standards. This revised strategy incorporates the latest federal and DOE orders (Executive Order [EO] 13514, “Federal Leadership in Environmental, Energy, and Economic Performance” [2009], EO 13423, “Strengthening Federal Environmental, Energy, and Transportation Management” [2007], and DOE Order 430.2B, “Departmental Energy, Renewable Energy, and Transportation Management” [2008]), the latest guidelines, trends, and observations in high performance building construction, and the latest changes to the Leadership in Energy and Environmental Design

  2. FUNDAMENTALS OF HIGH PERFORMANCE ORGANIZATIONS.

    Directory of Open Access Journals (Sweden)

    Maria Lúcia Gili Massi

    2013-06-01

    Full Text Available The objective of this article is to verify whether organizations’ high performance rests on their culture, which adjusts their cultural values, strategy, and external environment. A strong organizational culture has been reported as determinant of organizations’ performance. These studies approach the influence of values guiding and adjusting the organization’s strategic actions regarding its external environment. The bibliographic research showed that there are other variables impacting of organizations’ performance and it was concluded that the objective of this study was partially achieved.

  3. High Performance Bulk Thermoelectric Materials

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhifeng [Boston College, Chestnut Hill, MA (United States)

    2013-03-31

    Over 13 plus years, we have carried out research on electron pairing symmetry of superconductors, growth and their field emission property studies on carbon nanotubes and semiconducting nanowires, high performance thermoelectric materials and other interesting materials. As a result of the research, we have published 104 papers, have educated six undergraduate students, twenty graduate students, nine postdocs, nine visitors, and one technician.

  4. High-Performance Polymeric Materials.

    Science.gov (United States)

    1987-12-07

    interactions, Chain packing, Polybenzobisoxazoles Electrical conductivity Polybenzobisthiazoles Ceramic particles Chain flexibility Elastomer reinforcement...structures for the polybenzobisoxazole (PBO) and polybenzobisthiazole (PBT) chains originally synthesized and much studied because of their utility as...high-performance fibers and films. For cts-PBO, trans-PBO. and trans-PBT chains in their coplanar conformations, the band gaps in the axial direction

  5. High performance in software development

    CERN Document Server

    CERN. Geneva; Haapio, Petri; Liukkonen, Juha-Matti

    2015-01-01

    What are the ingredients of high-performing software? Software development, especially for large high-performance systems, is one the most complex tasks mankind has ever tried. Technological change leads to huge opportunities but challenges our old ways of working. Processing large data sets, possibly in real time or with other tight computational constraints, requires an efficient solution architecture. Efficiency requirements span from the distributed storage and large-scale organization of computation and data onto the lowest level of processor and data bus behavior. Integrating performance behavior over these levels is especially important when the computation is resource-bounded, as it is in numerics: physical simulation, machine learning, estimation of statistical models, etc. For example, memory locality and utilization of vector processing are essential for harnessing the computing power of modern processor architectures due to the deep memory hierarchies of modern general-purpose computers. As a r...

  6. High Performance Tools And Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Collette, M R; Corey, I R; Johnson, J R

    2005-01-24

    This goal of this project was to evaluate the capability and limits of current scientific simulation development tools and technologies with specific focus on their suitability for use with the next generation of scientific parallel applications and High Performance Computing (HPC) platforms. The opinions expressed in this document are those of the authors, and reflect the authors' current understanding and functionality of the many tools investigated. As a deliverable for this effort, we are presenting this report describing our findings along with an associated spreadsheet outlining current capabilities and characteristics of leading and emerging tools in the high performance computing arena. This first chapter summarizes our findings (which are detailed in the other chapters) and presents our conclusions, remarks, and anticipations for the future. In the second chapter, we detail how various teams in our local high performance community utilize HPC tools and technologies, and mention some common concerns they have about them. In the third chapter, we review the platforms currently or potentially available to utilize these tools and technologies on to help in software development. Subsequent chapters attempt to provide an exhaustive overview of the available parallel software development tools and technologies, including their strong and weak points and future concerns. We categorize them as debuggers, memory checkers, performance analysis tools, communication libraries, data visualization programs, and other parallel development aides. The last chapter contains our closing information. Included with this paper at the end is a table of the discussed development tools and their operational environment.

  7. Toward high performance graphene fibers.

    Science.gov (United States)

    Chen, Li; He, Yuling; Chai, Songgang; Qiang, Hong; Chen, Feng; Fu, Qiang

    2013-07-07

    Two-dimensional graphene and graphene-based materials have attracted tremendous interest, hence much attention has been drawn to exploring and applying their exceptional characteristics and properties. Integration of graphene sheets into macroscopic fibers is a very important way for their application and has received increasing interest. In this study, neat and macroscopic graphene fibers were continuously spun from graphene oxide (GO) suspensions followed by chemical reduction. By varying wet-spinning conditions, a series of graphene fibers were prepared, then, the structural features, mechanical and electrical performances of the fibers were investigated. We found the orientation of graphene sheets, the interaction between inter-fiber graphene sheets and the defects in the fibers have a pronounced effect on the properties of the fibers. Graphene fibers with excellent mechanical and electrical properties will yield great advances in high-tech applications. These findings provide guidance for the future production of high performance graphene fibers.

  8. High Efficiency, High Performance Clothes Dryer

    Energy Technology Data Exchange (ETDEWEB)

    Peter Pescatore; Phil Carbone

    2005-03-31

    This program covered the development of two separate products; an electric heat pump clothes dryer and a modulating gas dryer. These development efforts were independent of one another and are presented in this report in two separate volumes. Volume 1 details the Heat Pump Dryer Development while Volume 2 details the Modulating Gas Dryer Development. In both product development efforts, the intent was to develop high efficiency, high performance designs that would be attractive to US consumers. Working with Whirlpool Corporation as our commercial partner, TIAX applied this approach of satisfying consumer needs throughout the Product Development Process for both dryer designs. Heat pump clothes dryers have been in existence for years, especially in Europe, but have not been able to penetrate the market. This has been especially true in the US market where no volume production heat pump dryers are available. The issue has typically been around two key areas: cost and performance. Cost is a given in that a heat pump clothes dryer has numerous additional components associated with it. While heat pump dryers have been able to achieve significant energy savings compared to standard electric resistance dryers (over 50% in some cases), designs to date have been hampered by excessively long dry times, a major market driver in the US. The development work done on the heat pump dryer over the course of this program led to a demonstration dryer that delivered the following performance characteristics: (1) 40-50% energy savings on large loads with 35 F lower fabric temperatures and similar dry times; (2) 10-30 F reduction in fabric temperature for delicate loads with up to 50% energy savings and 30-40% time savings; (3) Improved fabric temperature uniformity; and (4) Robust performance across a range of vent restrictions. For the gas dryer development, the concept developed was one of modulating the gas flow to the dryer throughout the dry cycle. Through heat modulation in a

  9. Neo4j high performance

    CERN Document Server

    Raj, Sonal

    2015-01-01

    If you are a professional or enthusiast who has a basic understanding of graphs or has basic knowledge of Neo4j operations, this is the book for you. Although it is targeted at an advanced user base, this book can be used by beginners as it touches upon the basics. So, if you are passionate about taming complex data with the help of graphs and building high performance applications, you will be able to get valuable insights from this book.

  10. GHRSST Level 3C North Atlantic Regional Subskin Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on NOAA-19 (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) dataset for the North Atlantic Region (NAR) from the Advanced Very High Resolution Radiometer (AVHRR) on...

  11. High performance MEAs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-15

    The aim of the present project is through modeling, material and process development to obtain significantly better MEA performance and to attain the technology necessary to fabricate stable catalyst materials thereby providing a viable alternative to current industry standard. This project primarily focused on the development and characterization of novel catalyst materials for the use in high temperature (HT) and low temperature (LT) proton-exchange membrane fuel cells (PEMFC). New catalysts are needed in order to improve fuel cell performance and reduce the cost of fuel cell systems. Additional tasks were the development of new, durable sealing materials to be used in PEMFC as well as the computational modeling of heat and mass transfer processes, predominantly in LT PEMFC, in order to improve fundamental understanding of the multi-phase flow issues and liquid water management in fuel cells. An improved fundamental understanding of these processes will lead to improved fuel cell performance and hence will also result in a reduced catalyst loading to achieve the same performance. The consortium have obtained significant research results and progress for new catalyst materials and substrates with promising enhanced performance and fabrication of the materials using novel methods. However, the new materials and synthesis methods explored are still in the early research and development phase. The project has contributed to improved MEA performance using less precious metal and has been demonstrated for both LT-PEM, DMFC and HT-PEM applications. New novel approach and progress of the modelling activities has been extremely satisfactory with numerous conference and journal publications along with two potential inventions concerning the catalyst layer. (LN)

  12. High Performance Proactive Digital Forensics

    Science.gov (United States)

    Alharbi, Soltan; Moa, Belaid; Weber-Jahnke, Jens; Traore, Issa

    2012-10-01

    With the increase in the number of digital crimes and in their sophistication, High Performance Computing (HPC) is becoming a must in Digital Forensics (DF). According to the FBI annual report, the size of data processed during the 2010 fiscal year reached 3,086 TB (compared to 2,334 TB in 2009) and the number of agencies that requested Regional Computer Forensics Laboratory assistance increasing from 689 in 2009 to 722 in 2010. Since most investigation tools are both I/O and CPU bound, the next-generation DF tools are required to be distributed and offer HPC capabilities. The need for HPC is even more evident in investigating crimes on clouds or when proactive DF analysis and on-site investigation, requiring semi-real time processing, are performed. Although overcoming the performance challenge is a major goal in DF, as far as we know, there is almost no research on HPC-DF except for few papers. As such, in this work, we extend our work on the need of a proactive system and present a high performance automated proactive digital forensic system. The most expensive phase of the system, namely proactive analysis and detection, uses a parallel extension of the iterative z algorithm. It also implements new parallel information-based outlier detection algorithms to proactively and forensically handle suspicious activities. To analyse a large number of targets and events and continuously do so (to capture the dynamics of the system), we rely on a multi-resolution approach to explore the digital forensic space. Data set from the Honeynet Forensic Challenge in 2001 is used to evaluate the system from DF and HPC perspectives.

  13. 1,4-二氨基-3,6-二硝基吡唑[4,3-c]并吡唑的合成、热性能及量子化学研究%Synthesis, Thermal Performance and Quantum Chemistry Study on 1,4-Diamino-3,6-dinitropyrazolo[4,3-c]pyrazole

    Institute of Scientific and Technical Information of China (English)

    李亚南; 唐婷; 廉鹏; 罗义芬; 杨威; 王友兵; 李辉; 张志忠; 王伯周

    2012-01-01

    Using 3,5-dimethyl-4-aminopyrazole as primary substance, l,4-diamino-3,6-dinitropyrazolo[4,3-c]pyrazole (LLM-119) was synthesized by six steps of diazotisation, intramolecular cyclic condensation, nitration, oxidation, decarboxy-lation nitration and N-amination. The structures of intermediates and target compound were confirmed by means of IR, 'H NMR, I3C NMR and elemental analysis. The post-treatment method of 4-diazonium-3,5-dimethylpyrazole salt was improved, the yield was increased from 77.0% to 86.1% because of using the freezing crystallization method instead of extractive method, which could avoid the use of organic reagent and shorten operation process. The mechanism of N-amination reaction was discussed in order to analyze the reason of low-yield theoretically. Using differential scanning calorimetry (DSC) and thermogravimetric (TG) as thermal analysis methods, the thermal performance of LLM-119 was studied with thermal decomposition peak temperature of 232.05 ℃ and the results showed that LLM-119 had preferable thermal stability. The structure of LLM-119 was also estimated by a B3LYP method on 6-31G(d,p) basis set in order that its steady geometric configuration and bond order were obtained. The vibrational frequencies, IR spectra and thermodynamics properties in different temperatures of the system were obtained on the basis of vibrational analysis, the relations of the effects of temperatures on thermodynamics properties were also obtained. The density of LLM-119 calculated through the Monte-Carlo method was 1.8S g/cm3, which approached with the experiment value, and the predicted detonation velocity was 8733.94 m/s by the formula of Kamlet.%以自制的3,5-二甲基-4-氨基吡唑为原料,经重氮化、环化、硝化、氧化、脱羧硝化以及N-胺化等反应合成了1,4-二氨基-3,6-二硝基吡唑[4,3-c]并吡唑(LLM-119),采用红外光谱、核磁共振、质谱及元素分析等手段表征了中间体及目标物的结构;对4-

  14. High performance solar Stirling system

    Science.gov (United States)

    Stearns, J. W.; Haglund, R.

    1981-01-01

    A full-scale Dish-Stirling system experiment, at a power level of 25 kWe, has been tested during 1981 on the Test Bed Concentrator No. 2 at the Parabolic Dish Test Site, Edwards, CA. Test components, designed and developed primarily by industrial contractors for the Department of Energy, include an advanced Stirling engine driving an induction alternator, a directly-coupled solar receiver with a natural gas combustor for hybrid operation and a breadboard control system based on a programmable controller and standard utility substation components. The experiment demonstrated practicality of the solar Stirling application and high system performance into a utility grid. This paper describes the design and its functions, and the test results obtained.

  15. High Performance Perovskite Solar Cells.

    Science.gov (United States)

    Tong, Xin; Lin, Feng; Wu, Jiang; Wang, Zhiming M

    2016-05-01

    Perovskite solar cells fabricated from organometal halide light harvesters have captured significant attention due to their tremendously low device costs as well as unprecedented rapid progress on power conversion efficiency (PCE). A certified PCE of 20.1% was achieved in late 2014 following the first study of long-term stable all-solid-state perovskite solar cell with a PCE of 9.7% in 2012, showing their promising potential towards future cost-effective and high performance solar cells. Here, notable achievements of primary device configuration involving perovskite layer, hole-transporting materials (HTMs) and electron-transporting materials (ETMs) are reviewed. Numerous strategies for enhancing photovoltaic parameters of perovskite solar cells, including morphology and crystallization control of perovskite layer, HTMs design and ETMs modifications are discussed in detail. In addition, perovskite solar cells outside of HTMs and ETMs are mentioned as well, providing guidelines for further simplification of device processing and hence cost reduction.

  16. On the interplay between Si(110) epilayer atomic roughness and subsequent 3C-SiC growth direction

    Science.gov (United States)

    Khazaka, Rami; Michaud, Jean-François; Vennéguès, Philippe; Nguyen, Luan; Alquier, Daniel; Portail, Marc

    2016-11-01

    In this contribution, we performed the growth of a 3C-SiC/Si/3C-SiC layer stack on a Si(001) substrate by means of chemical vapor deposition. We show that, by tuning the growth conditions, the 3C-SiC epilayer can be grown along either the [111] direction or the [110] direction. The key parameter for the growth of the desired 3C-SiC orientation on the Si(110)/3C-SiC(001)/Si(001) heterostructure is highlighted and is linked to the Si epilayer surface morphology. The epitaxial relation between the layers has been identified using X-ray diffraction and transmission electron microscopy (TEM). We showed that, regardless of the top 3C-SiC epilayer orientation, domains rotated by 90° around the growth direction are present in the epilayer. Furthermore, the difference between the two 3C-SiC orientations was investigated by means of high magnification TEM. The results indicate that the faceted Si(110) epilayer surface morphology results in a (110)-oriented 3C-SiC epilayer, whereas a flat hetero-interface has been observed between 3C-SiC(111) and Si(110). The control of the top 3C-SiC growth direction can be advantageous for the development of new micro-electro-mechanical systems.

  17. ALMA Polarization Science Verification: 3C 286

    Science.gov (United States)

    Nagai, H.; Nakanishi, K.; Paladino, R.; Moellenbrock, G.; Fomalont, E.; Amigano, A.; Vlahakis, C.; Remijan, A.; ALMA Polarization Team

    2015-12-01

    The ALMA polarization science verification results on 3C 286 are presented. The measured polarization percentage and polarization position angle of the continuum emission at 1.3 mm are about 16% and 39 degrees, respectively. They are quite similar to those at longer wavelength, but seem to increase slightly. Similar trends were also found in the previous measurement using the IRAM 30-m telescope (Agudo et al. 2012). The final image rms on the polarization image is better than 0.1% of the total intensity, demonstrating the very high polarization sensitivity of ALMA.

  18. NCI's Transdisciplinary High Performance Scientific Data Platform

    Science.gov (United States)

    Evans, Ben; Antony, Joseph; Bastrakova, Irina; Car, Nicholas; Cox, Simon; Druken, Kelsey; Evans, Bradley; Fraser, Ryan; Ip, Alex; Kemp, Carina; King, Edward; Minchin, Stuart; Larraondo, Pablo; Pugh, Tim; Richards, Clare; Santana, Fabiana; Smillie, Jon; Trenham, Claire; Wang, Jingbo; Wyborn, Lesley

    2016-04-01

    additional communities practices, and a foundation for new exploratory developments. To that end, NCI is already participating in numerous current and emerging collaborations internationally including the Earth System Grid Federation (ESGF); Climate and Weather Data from International agencies such as NASA, NOAA, and UK Met Office; Remotely Sensed Satellite Earth Imaging through collaborations through GEOS and CEOS; EU-led Ocean Data Interoperability Platform (ODIP) and Horizon2020 Earth Server2 project; as well as broader data infrastructure community activities such as Research Data Alliance (RDA). Each research community is heavily engaged in international standards such as ISO, OGC and W3C, adopting community-led conventions for data, supporting improved data organisation such as controlled vocabularies, and creating workflows that use mature APIs and data services. NCI is engaging with these communities on NERDIP to ensure that such standards are applied uniformly and tested in practice by working with the variety of data and technologies. This includes benchmarking exemplar cases from individual communities, documenting their use of standards, and evaluating their practical use of the different technologies. Such a process fully establishes the functionality and performance, and is required to safely transition when improvements or rationalisation is required. Work is now underway to extend the NERDIP platform for better utilisation in the subsurface geophysical community, including maximizing national uptake, as well as better integration with international science platforms.

  19. Two-Dimensional Titanium Carbide/RGO Composite for High-Performance Supercapacitors.

    Science.gov (United States)

    Zhao, Chongjun; Wang, Qian; Zhang, Huang; Passerini, Stefano; Qian, Xiuzhen

    2016-06-22

    Ti3C2Tx, a 2D titanium carbide in the MXenes family, is obtained from Ti3AlC2 through selective etching of the Al layer. Due to its good conductivity and high volumetric capacitance, Ti3C2Tx is regarded as a promising candidate for supercapacitors. In this paper, the fabrication of Ti3C2Tx/RGO composites with different proportions of Ti3C2Tx and RGO is reported, in which RGO acts as a conductive "bridge" to connect different Ti3C2Tx blocks and a matrix to alleviate the volume change during charge/discharge process. In addition, RGO nanosheets can serve as a second nanoscale current collector and support as well for the electrode. The electrochemical performance of the as-fabricated Ti3C2Tx/RGO electrodes, characterized by CV, GCD, and EIS, are also reported. A highest specific capacitance (Cs) of 154.3 F/g at 2 A/g is obtained at the Ti3C2Tx: RGO weight ratio of 7:1 combined with an outstanding capacity retention (124.7 F/g) after 6000 cycles at 4 A/g.

  20. High Performance Torso Cooling Garment

    Science.gov (United States)

    Conger, Bruce; Makinen, Janice

    2016-01-01

    The concept proposed in this paper is to improve thermal efficiencies of the liquid cooling and ventilation garment (LCVG) in the torso area, which could facilitate removal of LCVG tubing from the arms and legs, thereby increasing suited crew member mobility. EVA space suit mobility in micro-gravity is challenging, and it becomes even more challenging in the gravity of Mars. By using shaped water tubes that greatly increase the contact area with the skin in the torso region of the body, the heat transfer efficiency can be increased. This increase in efficiency could provide the required liquid cooling via torso tubing only; no arm or leg LCVG tubing would be required. Benefits of this approach include increased crewmember mobility, enhanced evaporation cooling, increased comfort during Mars EVA tasks, and easing of the overly dry condition in the helmet associated with the Advanced Extravehicular Mobility Unit (EMU) ventilation loop currently under development. This report describes analysis and test activities performed to evaluate the potential improvements to the thermal performance of the LCVG. Analyses evaluated potential tube shapes for improving the thermal performance of the LCVG. The analysis results fed into the selection of flat flow strips to improve thermal contact with the skin of the suited test subject. Testing of small segments was performed to compare thermal performance of the tubing approach of the current LCVG to the flat flow strips proposed as the new concept. Results of the testing is presented along with recommendations for future development of this new concept.

  1. Learning Apache Solr high performance

    CERN Document Server

    Mohan, Surendra

    2014-01-01

    This book is an easy-to-follow guide, full of hands-on, real-world examples. Each topic is explained and demonstrated in a specific and user-friendly flow, from search optimization using Solr to Deployment of Zookeeper applications. This book is ideal for Apache Solr developers and want to learn different techniques to optimize Solr performance with utmost efficiency, along with effectively troubleshooting the problems that usually occur while trying to boost performance. Familiarity with search servers and database querying is expected.

  2. High-Performance Composite Chocolate

    Science.gov (United States)

    Dean, Julian; Thomson, Katrin; Hollands, Lisa; Bates, Joanna; Carter, Melvyn; Freeman, Colin; Kapranos, Plato; Goodall, Russell

    2013-01-01

    The performance of any engineering component depends on and is limited by the properties of the material from which it is fabricated. It is crucial for engineering students to understand these material properties, interpret them and select the right material for the right application. In this paper we present a new method to engage students with…

  3. Carpet Aids Learning in High Performance Schools

    Science.gov (United States)

    Hurd, Frank

    2009-01-01

    The Healthy and High Performance Schools Act of 2002 has set specific federal guidelines for school design, and developed a federal/state partnership program to assist local districts in their school planning. According to the Collaborative for High Performance Schools (CHPS), high-performance schools are, among other things, healthy, comfortable,…

  4. High performance Mo adsorbent PZC

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-10-01

    We have developed Mo adsorbents for natural Mo(n, {gamma}){sup 99}Mo-{sup 99m}Tc generator. Among them, we called the highest performance adsorbent PZC that could adsorb about 250 mg-Mo/g. In this report, we will show the structure, adsorption mechanism of Mo, and the other useful properties of PZC when you carry out the examination of Mo adsorption and elution of {sup 99m}Tc. (author)

  5. High performance Vernier racetrack resonators.

    Science.gov (United States)

    Boeck, Robert; Flueckiger, Jonas; Yun, Han; Chrostowski, Lukas; Jaeger, Nicolas A F

    2012-12-15

    We demonstrate record performance of series-coupled silicon racetrack resonators exhibiting the Vernier effect. Our device has an interstitial peak suppression (IPS) of 25.5 dB, which is 14.5 dB larger than previously reported results. We also demonstrate the relationship between the inter-ring gap distance and the IPS as well as the 3 dB bandwidth (BW) both theoretically and experimentally. Namely, we show that as the inter-ring gap distance increases, the IPS increases and the 3 dB BW decreases.

  6. High Performance JavaScript

    CERN Document Server

    Zakas, Nicholas

    2010-01-01

    If you're like most developers, you rely heavily on JavaScript to build interactive and quick-responding web applications. The problem is that all of those lines of JavaScript code can slow down your apps. This book reveals techniques and strategies to help you eliminate performance bottlenecks during development. You'll learn how to improve execution time, downloading, interaction with the DOM, page life cycle, and more. Yahoo! frontend engineer Nicholas C. Zakas and five other JavaScript experts -- Ross Harmes, Julien Lecomte, Steven Levithan, Stoyan Stefanov, and Matt Sweeney -- demonstra

  7. High-performance solar collector

    Science.gov (United States)

    Beekley, D. C.; Mather, G. R., Jr.

    1979-01-01

    Evacuated all-glass concentric tube collector using air or liquid transfer mediums is very efficient at high temperatures. Collector can directly drive existing heating systems that are presently driven by fossil fuel with relative ease of conversion and less expense than installation of complete solar heating systems.

  8. Functional High Performance Financial IT

    DEFF Research Database (Denmark)

    Berthold, Jost; Filinski, Andrzej; Henglein, Fritz

    2011-01-01

    , or applicablity, to finance. Research in HIPERFIT draws on and aims at producing new research in its different scientific fields, and it fosters synergies between them to deliver showcases of modern language technology and advanced functional methods with the potential for disruptive impact on an area......The world of finance faces the computational performance challenge of massively expanding data volumes, extreme response time requirements, and compute-intensive complex (risk) analyses. Simultaneously, new international regulatory rules require considerably more transparency and external...... auditability of financial institutions, including their software systems. To top it off, increased product variety and customisation necessitates shorter software development cycles and higher development productivity. In this paper, we report about HIPERFIT, a recently etablished strategic research center...

  9. Photosynthesis of C3, C3-C4, and C4 grasses at glacial CO2.

    Science.gov (United States)

    Pinto, Harshini; Sharwood, Robert E; Tissue, David T; Ghannoum, Oula

    2014-07-01

    Most physiology comparisons of C3 and C4 plants are made under current or elevated concentrations of atmospheric CO2 which do not reflect the low CO2 environment under which C4 photosynthesis has evolved. Accordingly, photosynthetic nitrogen (PNUE) and water (PWUE) use efficiency, and the activity of the photosynthetic carboxylases [Rubisco and phosphoenolpyruvate carboxylase (PEPC)] and decarboxylases [NADP-malic enzyme (NADP-ME) and phosphoenolpyruvate carboxykinase (PEP-CK)] were compared in eight C4 grasses with NAD-ME, PCK, and NADP-ME subtypes, one C3 grass, and one C3-C4 grass grown under ambient (400 μl l(-1)) and glacial (180 μl l(-1)) CO2. Glacial CO2 caused a smaller reduction of photosynthesis and a greater increase of stomatal conductance in C4 relative to C3 and C3-C4 species. Panicum bisulcatum (C3) acclimated to glacial [CO2] by doubling Rubisco activity, while Rubisco was unchanged in Panicum milioides (C3-C4), possibly due to its high leaf N and Rubisco contents. Glacial CO2 up-regulated Rubisco and PEPC activities in concert for several C4 grasses, while NADP-ME and PEP-CK activities were unchanged, reflecting the high control exerted by the carboxylases relative to the decarboxylases on the efficiency of C4 metabolism. Despite having larger stomatal conductance at glacial CO2, C4 species maintained greater PWUE and PNUE relative to C3-C4 and C3 species due to higher photosynthetic rates. Relative to other C4 subtypes, NAD-ME and PEP-CK grasses had the highest PWUE and PNUE, respectively; relative to C3, the C3-C4 grass had higher PWUE and similar PNUE at glacial CO2. Biomass accumulation was reduced by glacial CO2 in the C3 grass relative to the C3-C4 grass, while biomass was less reduced in NAD-ME grasses compared with NADP-ME and PCK grasses. Under glacial CO2, high resource use efficiency offers a key evolutionary advantage for the transition from C3 to C4 photosynthesis in water- and nutrient-limited environments.

  10. High performance polyethylene nanocomposite fibers

    Directory of Open Access Journals (Sweden)

    A. Dorigato

    2012-12-01

    Full Text Available A high density polyethylene (HDPE matrix was melt compounded with 2 vol% of dimethyldichlorosilane treated fumed silica nanoparticles. Nanocomposite fibers were prepared by melt spinning through a co-rotating twin screw extruder and drawing at 125°C in air. Thermo-mechanical and morphological properties of the resulting fibers were then investigated. The introduction of nanosilica improved the drawability of the fibers, allowing the achievement of higher draw ratios with respect to the neat matrix. The elastic modulus and creep stability of the fibers were remarkably improved upon nanofiller addition, with a retention of the pristine tensile properties at break. Transmission electronic microscope (TEM images evidenced that the original morphology of the silica aggregates was disrupted by the applied drawing.

  11. High performance soft magnetic materials

    CERN Document Server

    2017-01-01

    This book provides comprehensive coverage of the current state-of-the-art in soft magnetic materials and related applications, with particular focus on amorphous and nanocrystalline magnetic wires and ribbons and sensor applications. Expert chapters cover preparation, processing, tuning of magnetic properties, modeling, and applications. Cost-effective soft magnetic materials are required in a range of industrial sectors, such as magnetic sensors and actuators, microelectronics, cell phones, security, automobiles, medicine, health monitoring, aerospace, informatics, and electrical engineering. This book presents both fundamentals and applications to enable academic and industry researchers to pursue further developments of these key materials. This highly interdisciplinary volume represents essential reading for researchers in materials science, magnetism, electrodynamics, and modeling who are interested in working with soft magnets. Covers magnetic microwires, sensor applications, amorphous and nanocrystalli...

  12. HIGH-PERFORMANCE COATING MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA,T.

    2007-01-01

    Corrosion, erosion, oxidation, and fouling by scale deposits impose critical issues in selecting the metal components used at geothermal power plants operating at brine temperatures up to 300 C. Replacing these components is very costly and time consuming. Currently, components made of titanium alloy and stainless steel commonly are employed for dealing with these problems. However, another major consideration in using these metals is not only that they are considerably more expensive than carbon steel, but also the susceptibility of corrosion-preventing passive oxide layers that develop on their outermost surface sites to reactions with brine-induced scales, such as silicate, silica, and calcite. Such reactions lead to the formation of strong interfacial bonds between the scales and oxide layers, causing the accumulation of multiple layers of scales, and the impairment of the plant component's function and efficacy; furthermore, a substantial amount of time is entailed in removing them. This cleaning operation essential for reusing the components is one of the factors causing the increase in the plant's maintenance costs. If inexpensive carbon steel components could be coated and lined with cost-effective high-hydrothermal temperature stable, anti-corrosion, -oxidation, and -fouling materials, this would improve the power plant's economic factors by engendering a considerable reduction in capital investment, and a decrease in the costs of operations and maintenance through optimized maintenance schedules.

  13. Scheduling in high performance buffered crossbar switches

    NARCIS (Netherlands)

    Mhamdi, L.

    2007-01-01

    High performance routers are the basic building blocks of the Internet. Most high performance routers built today use crossbars and a centralized scheduler. Due to their high scheduling complexity, crossbar-based routers are not scalable and cannot keep pace with the explosive growth of the Internet

  14. High performance heat pump absorption cycles

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Longo, G.; Rossetto, L.

    1988-10-01

    Absorption heat pumps can provide high performances when operating in suitable cycles with multiple effects. This report describes some multistage cycles and evaluates the coefficient of performance realistically obtainable both in winter and summer working conditions.

  15. Attaining High Performance Communications A Vertical Approach

    CERN Document Server

    Gavrilovska, Ada

    2009-01-01

    Technological Advances and Problems of High Performance Communications. An ecosystem of solutions along a stack of technology layers. Cohesively collecting state-of-the-art contributions from leading researchers in industry, national laboratories, and academia, Attaining High Performance Communications: A Vertical Approach discusses various issues pertaining to high performance communications in a particular layer of a vertical stack. It explores efficient interconnection hardware, the architectural aspects of network adapters and their integration with processor cores, the design of scalable

  16. High performance carbon nanocomposites for ultracapacitors

    Science.gov (United States)

    Lu, Wen

    2012-10-02

    The present invention relates to composite electrodes for electrochemical devices, particularly to carbon nanotube composite electrodes for high performance electrochemical devices, such as ultracapacitors.

  17. High Performance Spaceflight Computing (HPSC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In 2012, the NASA Game Changing Development Program (GCDP), residing in the NASA Space Technology Mission Directorate (STMD), commissioned a High Performance...

  18. High Performance Work Systems, Performance and Innovativeness in Small Firms

    OpenAIRE

    Jan Kok; Deanne den Hartog

    2006-01-01

    The research presented in this paper focuses on the effectiveness of a high performance work system. This system is comprised of practices in the areas of extensiveness of staffing, performance based pay, pay level, job rotation, training and participation. In particular, this study focuses on the effects of such a system on the performance of small and medium-sized enterprises. Results of our study, among small and medium size enterprises in the Netherlands, show that firms with such a syste...

  19. Impacts of synthesis temperature and carbon content on the electrochemical performances of the Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C composite synthesized by a polyol method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Juan, E-mail: juanwang168@gmail.com [Shaanxi Key Laboratory of Nanomaterials and Nanotechnology, Xi' an University of Architecture and Technology, 710055 Xi' an (China); Zhang, Haipeng; Zheng, Siqi [Shaanxi Key Laboratory of Nanomaterials and Nanotechnology, Xi' an University of Architecture and Technology, 710055 Xi' an (China); Hojamberdiev, Mirabbos [Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori, Yokohama, Kanagawa 226-8503 (Japan); Ren, Bing; Xu, Yunhua; Shao, Chongyang [Shaanxi Key Laboratory of Nanomaterials and Nanotechnology, Xi' an University of Architecture and Technology, 710055 Xi' an (China)

    2014-12-15

    As a cathode material for Li-ion battery, Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} was synthesized by a polyol method using LiOH·H{sub 2}O, V{sub 2}O{sub 5}, NH{sub 4}H{sub 2}PO{sub 4}, sucrose, and ethylene glycol as starting materials. Under the polyol process, the impacts of synthesis parameters, including the sintering temperature, holding time, and carbon content, on the morphological evolution and electrochemical properties of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} were investigated. The XRD results show the formation of pure Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} with monoclinic crystal structure. The images of SEM show the similar-spherical morphology with uniform and optimized particles size, which greatly improves the electrochemical performance. The carbon coated on the Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} particles was clearly observed by electron microscopy. The particle size of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} powders gradually decreases with the increase of carbon content in composite. In the potential range of 3.0–4.3 V, the composite synthesized at 800 °C for 10 h with 10% carbon content shows the highest discharge capacity of 128 mAh g{sup −1} at 0.1C, which is nearly close to the theoretical capacity, and it remains fairly stable (more than 126 mAh g{sup −1}) even after the 20th cycles. Based on the results from the electrochemical impedance spectroscopy (EIS) analysis, the apparent diffusion coefficients of Li ions in the composite materials are between 1.82 × 10{sup −10} and 3.79 × 10{sup −9} cm{sup 2} s{sup −1}, which are much higher than those of olivine LiFePO{sub 4}. - Highlights: • As a cathode material, Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C was successfully synthesized by polyol method. • Impacts of synthesis temperature, holding time and carbon content were studied. • Electrochemical performance of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} was affected by particle morphology and size. • Li{sub 3}V{sub 2}(PO{sub 4

  20. Strategy Guideline: High Performance Residential Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Holton, J.

    2012-02-01

    The Strategy Guideline: High Performance Residential Lighting has been developed to provide a tool for the understanding and application of high performance lighting in the home. The high performance lighting strategies featured in this guide are drawn from recent advances in commercial lighting for application to typical spaces found in residential buildings. This guide offers strategies to greatly reduce lighting energy use through the application of high quality fluorescent and light emitting diode (LED) technologies. It is important to note that these strategies not only save energy in the home but also serve to satisfy the homeowner's expectations for high quality lighting.

  1. High Performance Grinding and Advanced Cutting Tools

    CERN Document Server

    Jackson, Mark J

    2013-01-01

    High Performance Grinding and Advanced Cutting Tools discusses the fundamentals and advances in high performance grinding processes, and provides a complete overview of newly-developing areas in the field. Topics covered are grinding tool formulation and structure, grinding wheel design and conditioning and applications using high performance grinding wheels. Also included are heat treatment strategies for grinding tools, using grinding tools for high speed applications, laser-based and diamond dressing techniques, high-efficiency deep grinding, VIPER grinding, and new grinding wheels.

  2. Capacitance of Ti3C2Tx MXene in ionic liquid electrolyte

    Science.gov (United States)

    Lin, Zifeng; Barbara, Daffos; Taberna, Pierre-Louis; Van Aken, Katherine L.; Anasori, Babak; Gogotsi, Yury; Simon, Patrice

    2016-09-01

    Ti3C2Tx MXene, a two-dimensional (2D) early transition metal carbide, has shown an extremely high volumetric capacitance in aqueous electrolytes, but in a narrow voltage window (less than 1.23 V). The utilization of MXene materials in ionic liquid electrolytes with a large voltage window has never been addressed. Here, we report the preparation of the Ti3C2Tx MXene ionogel film by vacuum filtration for use as supercapacitor electrodes operating in 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) neat ionic liquid electrolyte. Due to the disordered structure of the Ti3C2Tx hydrogel film and a stable spacing after vacuum drying, achieved through ionic liquid electrolyte immersion of the Ti3C2Tx hydrogel film, the Ti3C2Tx surface became accessible to EMI+ and TFSI- ions. A capacitance of 70 F g-1 together with a large voltage window of 3 V was obtained at a scan rate of 20 mV s-1 in neat EMI-TFSI electrolyte. The electrochemical signature indicates a capacitive behavior even at a high scan rate (500 mV s-1) and a high power performance. This work opens up the possibilities of using MXene materials with various ionic liquid electrolytes.

  3. China's High Performance Computer Standard Commission Established

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ China's High Performance Computer Standard Commission was established on March 28, 2007, under the guidance of the Science and Technology Bureau of the Ministry of Information Industry. It will prepare relevant professional standards on high performance computers to break through the monopoly in the field by foreign manufacturers and vendors.

  4. A High-performance Small Signal Amplifier

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    According to questions in the design of high quality small signal amplifier, this paper gave a new-type high performance small signal amplifier. The paper selected the operational amplifier of ICL Company and designed a new-type circuit with simple, low cost and excellent performance.

  5. Failure analysis of high performance ballistic fibers

    OpenAIRE

    Spatola, Jennifer S

    2015-01-01

    High performance fibers have a high tensile strength and modulus, good wear resistance, and a low density, making them ideal for applications in ballistic impact resistance, such as body armor. However, the observed ballistic performance of these fibers is much lower than the predicted values. Since the predictions assume only tensile stress failure, it is safe to assume that the stress state is affecting fiber performance. The purpose of this research was to determine if there are failure mo...

  6. Thermoluminescence dosimetric properties of a new thin beta detector (LiF:Mg, Cu, P; GR-200F) in comparison with highly sensitive Al{sub 2}O{sub 3}:C beta dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    El-Faramawy, N A [GSF-National Research Centre for Environment and Health, Institute for Radiation Protection, D-85758 Neuherberg (Germany); Goeksu, H Y [GSF-National Research Centre for Environment and Health, Institute for Radiation Protection, D-85758 Neuherberg (Germany); Panzer, W [GSF-National Research Centre for Environment and Health, Institute for Radiation Protection, D-85758 Neuherberg (Germany)

    2004-09-01

    There is an increasing need for efficient beta detectors to fulfil ICRU recommendations for new quantities especially in the field of medical physics and retrospective dosimetry. The thermoluminescence properties of thin LiF:Mg, Cu, P (GR-200F) tapes produced in 1998 by Sange Company, People's Republic of China, are investigated and compared with those of highly sensitive thin Al{sub 2}O{sub 3}:C beta detectors as regards their applicability in the detection of low energy photons and beta particles. The radiation dose response, minimum detectable dose, reproducibility of measurements and effect of residual signal at low dose are assessed for the possible low level beta dosimetry use. The radiation dose response and photon and beta detection efficiencies are tested under practical laboratory conditions. The effects of indoor fluorescent light and residual signal after the first read-out are investigated with a view to optimising handling conditions such as post-irradiation and pre-heating treatments for routine dosimetry. The photon energy responses of the detectors are investigated using 150 keV filtered x-rays and {sup 60}Co {gamma}-rays.

  7. Strategy Guideline. Partnering for High Performance Homes

    Energy Technology Data Exchange (ETDEWEB)

    Prahl, Duncan [IBACOS, Inc., Pittsburgh, PA (United States)

    2013-01-01

    High performance houses require a high degree of coordination and have significant interdependencies between various systems in order to perform properly, meet customer expectations, and minimize risks for the builder. Responsibility for the key performance attributes is shared across the project team and can be well coordinated through advanced partnering strategies. For high performance homes, traditional partnerships need to be matured to the next level and be expanded to all members of the project team including trades, suppliers, manufacturers, HERS raters, designers, architects, and building officials as appropriate. This guide is intended for use by all parties associated in the design and construction of high performance homes. It serves as a starting point and features initial tools and resources for teams to collaborate to continually improve the energy efficiency and durability of new houses.

  8. Analog circuit design designing high performance amplifiers

    CERN Document Server

    Feucht, Dennis

    2010-01-01

    The third volume Designing High Performance Amplifiers applies the concepts from the first two volumes. It is an advanced treatment of amplifier design/analysis emphasizing both wideband and precision amplification.

  9. High-performance computing using FPGAs

    CERN Document Server

    Benkrid, Khaled

    2013-01-01

    This book is concerned with the emerging field of High Performance Reconfigurable Computing (HPRC), which aims to harness the high performance and relative low power of reconfigurable hardware–in the form Field Programmable Gate Arrays (FPGAs)–in High Performance Computing (HPC) applications. It presents the latest developments in this field from applications, architecture, and tools and methodologies points of view. We hope that this work will form a reference for existing researchers in the field, and entice new researchers and developers to join the HPRC community.  The book includes:  Thirteen application chapters which present the most important application areas tackled by high performance reconfigurable computers, namely: financial computing, bioinformatics and computational biology, data search and processing, stencil computation e.g. computational fluid dynamics and seismic modeling, cryptanalysis, astronomical N-body simulation, and circuit simulation.     Seven architecture chapters which...

  10. Radiation Hard High Performance Optoelectronic Devices Project

    Data.gov (United States)

    National Aeronautics and Space Administration — High-performance, radiation-hard, widely-tunable integrated laser/modulator chip and large-area avalanche photodetectors (APDs) are key components of optical...

  11. High Performance Methane Thrust Chamber (HPMTC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop a High-Performance Methane Thrust Chamber (HPMRE) to meet the demands of advanced chemical propulsion systems for deep-space mission...

  12. Strip Casting of High Performance Structural Alloys

    Institute of Scientific and Technical Information of China (English)

    S S Park; J G Lee; Nack J Kim

    2004-01-01

    There exists a great need for the development of high performance alloys due to increasing demands for energy conservation and environmental protection. Application of strip casting shows a strong potential for the improvement of properties of existing alloys and also for the development of novel alloy systems with superior properties. The present paper reviews our Center's activities in the development of high performance alloys by strip casting. Examples include (1) Al alloys, (2) wrought Mg alloys, and (3) bulk metallic glass (BMG) alloys.

  13. Introduction to High Performance Scientific Computing

    OpenAIRE

    2016-01-01

    The field of high performance scientific computing lies at the crossroads of a number of disciplines and skill sets, and correspondingly, for someone to be successful at using high performance computing in science requires at least elementary knowledge of and skills in all these areas. Computations stem from an application context, so some acquaintance with physics and engineering sciences is desirable. Then, problems in these application areas are typically translated into linear algebraic, ...

  14. Architecture Analysis of High Performance Capacitors (POSTPRINT)

    Science.gov (United States)

    2009-07-01

    includes the measurement of heat dissipated from a recently developed fluorenyl polyester (FPE) capacitor under an AC excitation. II. Capacitor ...AFRL-RZ-WP-TP-2010-2100 ARCHITECTURE ANALYSIS OF HIGH PERFORMANCE CAPACITORS (POSTPRINT) Hiroyuki Kosai and Tyler Bixel UES, Inc...2009 4. TITLE AND SUBTITLE ARCHITECTURE ANALYSIS OF HIGH PERFORMANCE CAPACITORS (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c

  15. Study on performance of Li3V2(PO4)3/C composite material for lithium-ion batteries%Li3V2(PO4)3/C复合材料及其电池性能研究

    Institute of Scientific and Technical Information of China (English)

    任丽彬; 杨凯; 彭庆文; 卢志威; 刘兴江

    2012-01-01

    Li3V2(PO4)3/c composite cathode material was prepared by spray drying method. The characteristic of the Li3V,(PO4)3/C composite material was investigated by means of XRO, SEM and DSC. The 18650 lithium-ion batteries were prepared with Li3V2(PO4)3/C composite cathode material and CMS-G25 anodic material. The rate ability, cycling performance and safety characteristic of the LIB were studied. The results indicate that the Li3V2 (PO4)3/C composite material is pure monoclinic phase, and the spherical secondary particles can be prepared by spray drying method. The samples have excellent thermal stability, the exotherm in the 4.3 V and 4.7 V charged state is 240.1 J/g and 259.4 J/g, respectively. The 18650 LIB shows good high-rate ability, cycling performance and safety characteristic. The discharge capacity of 15 C/1 C is 95%, the discharge capacity retention is 95.02% after 100 cycles. The punch, nail, short circuit and heat test were carried out; the 18650 LIB had no fire and no explosion.z%采用喷雾干燥法合成了Li3V2 (PO4)3/C复合正极材料,通过X射线衍射光谱法(XRD)、扫描电子显微镜法(SEM)和差示扫描量热法(DSC)对合成的复合材料进行了表征;以Li3V2(PO4)3/C复合材料为正极、CMS-G25为负极,制备18650锂离子电池,考察了该电池的倍率性能、循环性能和安全性能.结果表明:合成的Li3V2(PO4)3/C复合材料为单斜晶体结构,可以得到微米级的球形Li3V2(PO4)3/C二次颗粒;该复合材料具有优异的热稳定性,在4.3 V和4.7 V满电态下的放热量分别为240.1 J/g和259.4 J/g,明显低于其它几种正极材料.制备的18650锂离子电池具有良好的高倍率放电性能、循环性能,其15C/1 C放电容量可达95%,100次容量保持率为95.02%;同时还具有优异的安全性能,顺利通过了挤压、针刺、短路、热箱等实验,电池均不爆炸、不起火.

  16. Research on High Performance New Refractories

    Institute of Scientific and Technical Information of China (English)

    Zhong Xiangchong

    2007-01-01

    @@ At the age of 86,Prof.Zhong Xiangchong has his new book-"Research on High Performance New Refractories" published by Henan Science and Technology Publishing House to commemorate his 65 years service in the refractories science and technology including the recent 6 years at High Temperature Ceramics Institute which he founded in Zhengzhou University in 2001.

  17. High Performance Work Systems for Online Education

    Science.gov (United States)

    Contacos-Sawyer, Jonna; Revels, Mark; Ciampa, Mark

    2010-01-01

    The purpose of this paper is to identify the key elements of a High Performance Work System (HPWS) and explore the possibility of implementation in an online institution of higher learning. With the projected rapid growth of the demand for online education and its importance in post-secondary education, providing high quality curriculum, excellent…

  18. Teacher Accountability at High Performing Charter Schools

    Science.gov (United States)

    Aguirre, Moises G.

    2016-01-01

    This study will examine the teacher accountability and evaluation policies and practices at three high performing charter schools located in San Diego County, California. Charter schools are exempted from many laws, rules, and regulations that apply to traditional school systems. By examining the teacher accountability systems at high performing…

  19. Noise of High Performance Aircraft at Afterburner

    Science.gov (United States)

    2016-02-10

    aircraft carrier, navy personnel work in close proximity to high performance jets at takeoffs and landings. The noise level emitted by these jets is...any major differences between the dominant noise components of these jets and those of a standard high temperature laboratory supersonic jet . It is...noise. For the F18E aircraft, we find that its noise, at high engine power settings, also includes new noise components in addition to the usual fine

  20. A low-cost cementite (Fe3C) nanocrystal@N-doped graphitic carbon electrocatalyst for efficient oxygen reduction.

    Science.gov (United States)

    Wu, Tianxing; Zhang, Haimin; Zhang, Xian; Zhang, Yunxia; Zhao, Huijun; Wang, Guozhong

    2015-11-01

    In this work, chitosan whiskers (CWs) were first extracted using low-cost and earth-abundant crab shells as materials by a series of chemical processes, and then assembled into chitosan whisker microspheres (CWMs) via a simple photochemical polymerization approach. Subsequently, a cementite (Fe3C) nanocrystal@N-doped graphitic carbon (Fe3C@NGC) nanocomposite was successfully fabricated by high temperature pyrolysis of CWMs adsorbed with ferric acetylacetonate (Fe(acac)3) at 900 °C. It was found that a suitable growth atmosphere generated inside CWMs during high temperature pyrolysis is critically important to form Fe3C nanocrystal cores, concurrently accompanying a structural transformation from chitosan whiskers to mesoporous graphitic carbon shells with natural nitrogen (N) doping properties, resulting in the formation of a core-shell structure Fe3C@NGC nanocomposite. The resulting samples were evaluated as electrocatalysts for oxygen reduction reaction (ORR). In comparison with sole N-doped graphitic carbon without Fe3C nanocrystals obtained by direct pyrolysis of chitosan whisker microspheres at 900 °C (CWMs-900), Fe3C@NGC showed significantly improved ORR catalytic activity. The tolerance to fuel cell molecules (e.g., methanol) and the durability of Fe3C@NGC are obviously superior to commercial Pt/C catalysts in alkaline media. The high ORR performance of Fe3C@NGC could be due to its large surface area (313.7 m(2) g(-1)), a synergistic role of Fe3C nanocrystals, N doping in graphitic carbon creating more catalytic active sites, and a porous structure of the nanocomposite facilitating mass transfer to efficiently improve the utilization of these catalytic active sites.

  1. Position Measurements of the Core in 3C 66B

    Indian Academy of Sciences (India)

    G.-Y. Zhao; Y.-J. Chen; Z.-Q. Shen; H. Sudou; S. Iguchi; Y. Murata; Y. Taniguchi

    2011-03-01

    It was argued that 3C 66B, a nearby radio galaxy, harbors a supermassive black hole binary (SMBHB). To investigate this, a 4-epoch VLBA phase referencing imaging observation was performed in 2004–2005. Here we present some preliminary results of this project. We found a large position difference compared to previous results.

  2. NATO-3C/Delta launch

    Science.gov (United States)

    1978-01-01

    NATO-3C, the third in a series of NATO defense-related communication satellites, is scheduled to be launched on a delta vehicle from the Eastern Test Range no earlier than November 15, 1978. NATO-3A and -3B were successfully launched by Delta vehicles in April 1976 and January 1977, respectively. The NATO-3C spacecraft will be capable of transmitting voice, data, facsimile, and telex messages among military ground stations. The launch vehicle for the NATO-3C mission will be the Delta 2914 configuration. The launch vehicle is to place the spacecraft in a synchronous transfer orbit. The spacecraft Apogee Kick motor is to be fired at fifth transfer orbit apogee to circularize its orbit at geosynchronous altitude of 35,900 km(22,260 miles) above the equator over the Atlantic Ocean somewhere between 45 and 50 degrees W longitude.

  3. Basic prinicipal of high performance liquid chromatography

    OpenAIRE

    Ivanova, Violeta

    2016-01-01

    High-performance liquid chromatography (HPLC) is an analytical technique based on the separation of molecules due to differences in their structure and/or composition. Separation is performed between two phases, mobile and stationary. The molecules in the sample have different affinities and interactions with the stationary support, leading to separation of molecules. Compounds which are longer retained at the stationary phase will elute later, compared to those which are distributed into the...

  4. vSphere high performance cookbook

    CERN Document Server

    Sarkar, Prasenjit

    2013-01-01

    vSphere High Performance Cookbook is written in a practical, helpful style with numerous recipes focusing on answering and providing solutions to common, and not-so common, performance issues and problems.The book is primarily written for technical professionals with system administration skills and some VMware experience who wish to learn about advanced optimization and the configuration features and functions for vSphere 5.1.

  5. High Performance Interconnect Network for Tianhe System

    Institute of Scientific and Technical Information of China (English)

    廖湘科; 庞征斌; 王克非; 卢宇彤; 谢旻; 夏军; 董德尊; 所光

    2015-01-01

    In this paper, we present the Tianhe-2 interconnect network and message passing services. We describe the architecture of the router and network interface chips, and highlight a set of hardware and software features effectively supporting high performance communications, ranging over remote direct memory access, collective optimization, hardware-enable reliable end-to-end communication, user-level message passing services, etc. Measured hardware performance results are also presented.

  6. Optimizations for High Performance Network Virtualization

    Institute of Scientific and Technical Information of China (English)

    Fan-Fu Zhou; Ru-Hui Ma; Jian Li; Li-Xia Chen; Wei-Dong Qiu; Hai-Bing Guan

    2016-01-01

    The increasing requirements of intensive interoperaterbility among the distributed nodes desiderate the high performance network connections, owing to the substantial growth of cloud computing and datacenters. Network I/O virtualization aggregates the network resource and separates it into manageable parts for particular servers or devices, which provides effective consolidation and elastic management with high agility, flexibility and scalability as well as reduced cost and cabling. However, both network I/O virtualization aggregation and the increasing network speed incur higher traffic density, which generates a heavy system stress for I/O data moving and I/O event processing. Consequently, many researchers have dedicated to enhancing the system performance and alleviating the system overhead for high performance networking virtualization. This paper first elaborates the mainstreaming I/O virtualization methodologies, including device emulation, split-driver model and hardware assisted model. Then, the paper discusses and compares their specific advantages in addition to performance bottlenecks in practical utilities. This paper mainly focuses on the comprehensive survey of state-of-the-art approaches for performance optimizations and improvements as well as the portability management for network I/O virtualization. The approaches include various novel data delivery schemes, overhead mitigations for interrupt processing and adequate resource allocations for dynamic network states. Finally, we highlight the diversity of I/O virtualization besides the performance improvements in network virtualization infrastructure.

  7. Analyzing polarization swings in 3C 279

    CERN Document Server

    Kiehlmann, S; Jorstad, S G; Sokolovsky, K V; Schinzel, F K; Agudo, I; Arkharov, A A; Benitez, E; Berdyugin, A; Blinov, D A; Bochkarev, N G; Borman, G A; Burenkov, A N; Casadio, C; Doroshenko, V T; Efimova, N V; Fukazawa, Y; Gomez, J L; Hagen-Thorn, V A; Heidt, J; Hiriart, D; Itoh, R; Joshi, M; Kimeridze, G N; Konstantinova, T S; Kopatskaya, E N; Korobtsev, I V; Kovalev, Y Y; Krajci, T; Kurtanidze, O; Kurtanidze, S O; Larionov, V M; Larionova, E G; Larionova, L V; Lindfors, E; Lopez, J M; Marscher, A P; McHardy, I M; Molina, S N; Morozova, D A; Nazarov, S V; Nikolashvili, M G; Nilsson, K; Pulatova, N G; Reinthal, R; Sadun, A; Sergeev, S G; Sigua, L A; Sorcia, M; Spiridonova, O I; Takalo, L O; Taylor, B; Troitsky, I S; Ugolkova, L S; Zensus, J A; Zhdanova, V E

    2013-01-01

    Quasar 3C 279 is known to exhibit episodes of optical polarization angle rotation. We present new, well-sampled optical polarization data for 3C 279 and introduce a method to distinguish between random and deterministic electric vector position angle (EVPA) variations. We observe EVPA rotations in both directions with different amplitudes and find that the EVPA variation shows characteristics of both random and deterministic cases. Our analysis indicates that the EVPA variation is likely dominated by a random process in the low brightness state of the jet and by a deterministic process in the flaring state.

  8. Dawning4000A high performance computer

    Institute of Scientific and Technical Information of China (English)

    SUN Ninghui; MENG Dan

    2007-01-01

    Dawning4000A is an AMD Opteron-based Linux Cluster with 11.2Tflops peak performance and 8.06Tflops Linpack performance.It was developed for the Shanghai Supercomputer Center (SSC)as one of the computing power stations of the China National Grid (CNGrid)project.The Massively Cluster Computer (MCC)architecture is proposed to put added-value on the industry standard system.Several grid-enabling components are developed to support the running environment of the CNGrid.It is an achievement for a high performance computer with the low-cost approach.

  9. Achieving High Performance Perovskite Solar Cells

    Science.gov (United States)

    Yang, Yang

    2015-03-01

    Recently, metal halide perovskite based solar cell with the characteristics of rather low raw materials cost, great potential for simple process and scalable production, and extreme high power conversion efficiency (PCE), have been highlighted as one of the most competitive technologies for next generation thin film photovoltaic (PV). In UCLA, we have realized an efficient pathway to achieve high performance pervoskite solar cells, where the findings are beneficial to this unique materials/devices system. Our recent progress lies in perovskite film formation, defect passivation, transport materials design, interface engineering with respect to high performance solar cell, as well as the exploration of its applications beyond photovoltaics. These achievements include: 1) development of vapor assisted solution process (VASP) and moisture assisted solution process, which produces perovskite film with improved conformity, high crystallinity, reduced recombination rate, and the resulting high performance; 2) examination of the defects property of perovskite materials, and demonstration of a self-induced passivation approach to reduce carrier recombination; 3) interface engineering based on design of the carrier transport materials and the electrodes, in combination with high quality perovskite film, which delivers 15 ~ 20% PCEs; 4) a novel integration of bulk heterojunction to perovskite solar cell to achieve better light harvest; 5) fabrication of inverted solar cell device with high efficiency and flexibility and 6) exploration the application of perovskite materials to photodetector. Further development in film, device architecture, and interfaces will lead to continuous improved perovskite solar cells and other organic-inorganic hybrid optoelectronics.

  10. High performance parallel I/O

    CERN Document Server

    Prabhat

    2014-01-01

    Gain Critical Insight into the Parallel I/O EcosystemParallel I/O is an integral component of modern high performance computing (HPC), especially in storing and processing very large datasets to facilitate scientific discovery. Revealing the state of the art in this field, High Performance Parallel I/O draws on insights from leading practitioners, researchers, software architects, developers, and scientists who shed light on the parallel I/O ecosystem.The first part of the book explains how large-scale HPC facilities scope, configure, and operate systems, with an emphasis on choices of I/O har

  11. High Performance Binder for EMCDB Propellants

    Directory of Open Access Journals (Sweden)

    V. K. Bhat

    1995-01-01

    Full Text Available A novel block polymer has been synthesised from caprolactone using hydroxy terminated polybutadiene as ring opening initiator. Usefulness of this polymer as propellant binder has been studied by generating data on physico-chemical properties of the polymer. The polymer exhibited high miscibility with nitrate ester and high solid loading capability. Preliminary data generated on typical propellant formulation indicated higher performance as compared to composite propellant.

  12. LIQUID ARGON CALORIMETER PERFORMANCE AT HIGH RATES

    CERN Document Server

    Kukhtin, V; The ATLAS collaboration

    2011-01-01

    The performance of the ATLAS liquid argon endcap and forward calorimeters has been projected at the planned high luminosity LHC option HL-LHC by exposing small calorimeter modules of the electromagnetic, hadronic, and forward calorimeters to high intensity proton beams at IHEP/Protvino accelerator. The results of HV current and of pulse shape analysis, and also the dependence of signal amplitude on beam intensity are presented.

  13. Strategy Guideline: Partnering for High Performance Homes

    Energy Technology Data Exchange (ETDEWEB)

    Prahl, D.

    2013-01-01

    High performance houses require a high degree of coordination and have significant interdependencies between various systems in order to perform properly, meet customer expectations, and minimize risks for the builder. Responsibility for the key performance attributes is shared across the project team and can be well coordinated through advanced partnering strategies. For high performance homes, traditional partnerships need to be matured to the next level and be expanded to all members of the project team including trades, suppliers, manufacturers, HERS raters, designers, architects, and building officials as appropriate. In an environment where the builder is the only source of communication between trades and consultants and where relationships are, in general, adversarial as opposed to cooperative, the chances of any one building system to fail are greater. Furthermore, it is much harder for the builder to identify and capitalize on synergistic opportunities. Partnering can help bridge the cross-functional aspects of the systems approach and achieve performance-based criteria. Critical success factors for partnering include support from top management, mutual trust, effective and open communication, effective coordination around common goals, team building, appropriate use of an outside facilitator, a partnering charter progress toward common goals, an effective problem-solving process, long-term commitment, continuous improvement, and a positive experience for all involved.

  14. L3+C air shower array

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    Photo 01: a view of the L3+C air shower array; 50 scintillators on the roof of the SX-hall above L3. Photo 02: view of one of the detectors of the array.Photo 04: detectors seen against the background of the LEP Point 2 facilities.

  15. Project materials [Commercial High Performance Buildings Project

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-01-01

    The Consortium for High Performance Buildings (ChiPB) is an outgrowth of DOE'S Commercial Whole Buildings Roadmapping initiatives. It is a team-driven public/private partnership that seeks to enable and demonstrate the benefit of buildings that are designed, built and operated to be energy efficient, environmentally sustainable, superior quality, and cost effective.

  16. Debugging a high performance computing program

    Science.gov (United States)

    Gooding, Thomas M.

    2013-08-20

    Methods, apparatus, and computer program products are disclosed for debugging a high performance computing program by gathering lists of addresses of calling instructions for a plurality of threads of execution of the program, assigning the threads to groups in dependence upon the addresses, and displaying the groups to identify defective threads.

  17. An Introduction to High Performance Fortran

    Directory of Open Access Journals (Sweden)

    John Merlin

    1995-01-01

    Full Text Available High Performance Fortran (HPF is an informal standard for extensions to Fortran 90 to assist its implementation on parallel architectures, particularly for data-parallel computation. Among other things, it includes directives for specifying data distribution across multiple memories, and concurrent execution features. This article provides a tutorial introduction to the main features of HPF.

  18. Towards High Performance in Industrial Refrigeration Systems

    DEFF Research Database (Denmark)

    Thybo, C.; Izadi-Zamanabadi, Roozbeh; Niemann, H.

    2002-01-01

    Achieving high performance in complex industrial systems requires information manipulation at different system levels. The paper shows how different models of same subsystems, but using different quality of information/data, are used for fault diagnosis as well as robust control design...... in industrial refrigeration systems....

  19. Toward High Performance in Industrial Refrigeration Systems

    DEFF Research Database (Denmark)

    Thybo, C.; Izadi-Zamanabadi, Roozbeh; Niemann, H.

    2002-01-01

    Achieving high performance in complex industrial systems requires information manipulation at different system levels. The paper shows how different models of same subsystems, but using different quality of information/data, are used for fault diagnosis as well as robust control design...... in industrial refrigeration systems....

  20. High Performance Electronics on Flexible Silicon

    KAUST Repository

    Sevilla, Galo T.

    2016-09-01

    Over the last few years, flexible electronic systems have gained increased attention from researchers around the world because of their potential to create new applications such as flexible displays, flexible energy harvesters, artificial skin, and health monitoring systems that cannot be integrated with conventional wafer based complementary metal oxide semiconductor processes. Most of the current efforts to create flexible high performance devices are based on the use of organic semiconductors. However, inherent material\\'s limitations make them unsuitable for big data processing and high speed communications. The objective of my doctoral dissertation is to develop integration processes that allow the transformation of rigid high performance electronics into flexible ones while maintaining their performance and cost. In this work, two different techniques to transform inorganic complementary metal-oxide-semiconductor electronics into flexible ones have been developed using industry compatible processes. Furthermore, these techniques were used to realize flexible discrete devices and circuits which include metal-oxide-semiconductor field-effect-transistors, the first demonstration of flexible Fin-field-effect-transistors, and metal-oxide-semiconductors-based circuits. Finally, this thesis presents a new technique to package, integrate, and interconnect flexible high performance electronics using low cost additive manufacturing techniques such as 3D printing and inkjet printing. This thesis contains in depth studies on electrical, mechanical, and thermal properties of the fabricated devices.

  1. Using LEADS to shift to high performance.

    Science.gov (United States)

    Fenwick, Shauna; Hagge, Erna

    2016-03-01

    Health systems across Canada are tasked to measure results of all their strategic initiatives. Included in most strategic plans is leadership development. How to measure leadership effectiveness in relation to organizational objectives is key in determining organizational effectiveness. The following findings offer considerations for a 21(st)-century approach to shifting to high-performance systems.

  2. Commercial Buildings High Performance Rooftop Unit Challenge

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-12-16

    The U.S. Department of Energy (DOE) and the Commercial Building Energy Alliances (CBEAs) are releasing a new design specification for high performance rooftop air conditioning units (RTUs). Manufacturers who develop RTUs based on this new specification will find strong interest from the commercial sector due to the energy and financial savings.

  3. High performance computing on vector systems

    CERN Document Server

    Roller, Sabine

    2008-01-01

    Presents the developments in high-performance computing and simulation on modern supercomputer architectures. This book covers trends in hardware and software development in general and specifically the vector-based systems and heterogeneous architectures. It presents innovative fields like coupled multi-physics or multi-scale simulations.

  4. High Performance Builder Spotlight: Imagine Homes

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-01-01

    Imagine Homes, working with the DOE's Building America research team member IBACOS, has developed a system that can be replicated by other contractors to build affordable, high-performance homes. Imagine Homes has used the system to produce more than 70 Builders Challenge-certified homes per year in San Antonio over the past five years.

  5. High-Performance, Low Environmental Impact Refrigerants

    Science.gov (United States)

    McCullough, E. T.; Dhooge, P. M.; Glass, S. M.; Nimitz, J. S.

    2001-01-01

    Refrigerants used in process and facilities systems in the US include R-12, R-22, R-123, R-134a, R-404A, R-410A, R-500, and R-502. All but R-134a, R-404A, and R-410A contain ozone-depleting substances that will be phased out under the Montreal Protocol. Some of the substitutes do not perform as well as the refrigerants they are replacing, require new equipment, and have relatively high global warming potentials (GWPs). New refrigerants are needed that addresses environmental, safety, and performance issues simultaneously. In efforts sponsored by Ikon Corporation, NASA Kennedy Space Center (KSC), and the US Environmental Protection Agency (EPA), ETEC has developed and tested a new class of refrigerants, the Ikon (registered) refrigerants, based on iodofluorocarbons (IFCs). These refrigerants are nonflammable, have essentially zero ozone-depletion potential (ODP), low GWP, high performance (energy efficiency and capacity), and can be dropped into much existing equipment.

  6. Dynamic and static behaviors of N-Z-N σ(3c-4e) (Z = S, Se, and Te) interactions: atoms-in-molecules dual functional analysis with high-resolution X-ray diffraction determination of electron densities for 2-(2-pyridylimino)-2H-1,2,4-thiadiazolo[2,3-a]pyridine.

    Science.gov (United States)

    Nakanishi, Waro; Hayashi, Satoko; Pitak, Mateusz B; Hursthouse, Michael B; Coles, Simon J

    2011-10-27

    The structure of 2-(2-pyridylimino)-2H-1,2,4-thiadiazolo[2,3-a]pyridine (NSN) indicates that the molecule has a planar geometry with a linear N···S···N linkage, creating a tetracyclic structure of the formal C(2v) symmetry. To clarify the nature of the NSN σ(3c-4e) bonding, together with the related NSeN and NTeN, the dynamic and static behaviors are investigated by applying atoms-in-molecules (AIM) dual functional analysis to both the fully optimized and perturbed structures. The structures were optimized computationally, retaining C(2v) symmetry. All bond critical points are detected as expected and exhibited on both sides of the N···Z···N moiety which supports the formation of NZN σ(3c-4e). It is confirmed that N···S···N is of the covalent nature close to Me(2)S(+)-∗-Cl or Me(2)Se(+)-∗-Br, whereas N···Se···N and N···Te···N have the (regular) CS nature close to the CT adducts of Me(2)S(-∗-Cl)(2) (TBP) and Me(2)Se-∗-Br(2) (MC), respectively. An experimental high-resolution charge density determination has been performed on NSN, which thoroughly supports the theoretical results. Very similar results are obtained in the analogous pyrimidyl derivatives for N···S···N, N···Se···N, and N···Te···N. AIM dual functional analysis, as validated by experimental high-resolution charge densities, is thus confirmed to be an excellent method to elucidate the nature of these interactions.

  7. Strategy Guideline. High Performance Residential Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Holton, J. [IBACOS, Inc., Pittsburgh, PA (United States)

    2012-02-01

    This report has been developed to provide a tool for the understanding and application of high performance lighting in the home. The strategies featured in this guide are drawn from recent advances in commercial lighting for application to typical spaces found in residential buildings. This guide offers strategies to greatly reduce lighting energy use through the application of high quality fluorescent and light emitting diode (LED) technologies. It is important to note that these strategies not only save energy in the home but also serve to satisfy the homeowner’s expectations for high quality lighting.

  8. NINJA: Java for High Performance Numerical Computing

    Directory of Open Access Journals (Sweden)

    José E. Moreira

    2002-01-01

    Full Text Available When Java was first introduced, there was a perception that its many benefits came at a significant performance cost. In the particularly performance-sensitive field of numerical computing, initial measurements indicated a hundred-fold performance disadvantage between Java and more established languages such as Fortran and C. Although much progress has been made, and Java now can be competitive with C/C++ in many important situations, significant performance challenges remain. Existing Java virtual machines are not yet capable of performing the advanced loop transformations and automatic parallelization that are now common in state-of-the-art Fortran compilers. Java also has difficulties in implementing complex arithmetic efficiently. These performance deficiencies can be attacked with a combination of class libraries (packages, in Java that implement truly multidimensional arrays and complex numbers, and new compiler techniques that exploit the properties of these class libraries to enable other, more conventional, optimizations. Two compiler techniques, versioning and semantic expansion, can be leveraged to allow fully automatic optimization and parallelization of Java code. Our measurements with the NINJA prototype Java environment show that Java can be competitive in performance with highly optimized and tuned Fortran code.

  9. High performance anode for advanced Li batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lake, Carla [Applied Sciences, Inc., Cedarville, OH (United States)

    2015-11-02

    The overall objective of this Phase I SBIR effort was to advance the manufacturing technology for ASI’s Si-CNF high-performance anode by creating a framework for large volume production and utilization of low-cost Si-coated carbon nanofibers (Si-CNF) for the battery industry. This project explores the use of nano-structured silicon which is deposited on a nano-scale carbon filament to achieve the benefits of high cycle life and high charge capacity without the consequent fading of, or failure in the capacity resulting from stress-induced fracturing of the Si particles and de-coupling from the electrode. ASI’s patented coating process distinguishes itself from others, in that it is highly reproducible, readily scalable and results in a Si-CNF composite structure containing 25-30% silicon, with a compositionally graded interface at the Si-CNF interface that significantly improve cycling stability and enhances adhesion of silicon to the carbon fiber support. In Phase I, the team demonstrated the production of the Si-CNF anode material can successfully be transitioned from a static bench-scale reactor into a fluidized bed reactor. In addition, ASI made significant progress in the development of low cost, quick testing methods which can be performed on silicon coated CNFs as a means of quality control. To date, weight change, density, and cycling performance were the key metrics used to validate the high performance anode material. Under this effort, ASI made strides to establish a quality control protocol for the large volume production of Si-CNFs and has identified several key technical thrusts for future work. Using the results of this Phase I effort as a foundation, ASI has defined a path forward to commercialize and deliver high volume and low-cost production of SI-CNF material for anodes in Li-ion batteries.

  10. A Linux Workstation for High Performance Graphics

    Science.gov (United States)

    Geist, Robert; Westall, James

    2000-01-01

    The primary goal of this effort was to provide a low-cost method of obtaining high-performance 3-D graphics using an industry standard library (OpenGL) on PC class computers. Previously, users interested in doing substantial visualization or graphical manipulation were constrained to using specialized, custom hardware most often found in computers from Silicon Graphics (SGI). We provided an alternative to expensive SGI hardware by taking advantage of third-party, 3-D graphics accelerators that have now become available at very affordable prices. To make use of this hardware our goal was to provide a free, redistributable, and fully-compatible OpenGL work-alike library so that existing bodies of code could simply be recompiled. for PC class machines running a free version of Unix. This should allow substantial cost savings while greatly expanding the population of people with access to a serious graphics development and viewing environment. This should offer a means for NASA to provide a spectrum of graphics performance to its scientists, supplying high-end specialized SGI hardware for high-performance visualization while fulfilling the requirements of medium and lower performance applications with generic, off-the-shelf components and still maintaining compatibility between the two.

  11. The path toward HEP High Performance Computing

    CERN Document Server

    Apostolakis, John; Carminati, Federico; Gheata, Andrei; Wenzel, Sandro

    2014-01-01

    High Energy Physics code has been known for making poor use of high performance computing architectures. Efforts in optimising HEP code on vector and RISC architectures have yield limited results and recent studies have shown that, on modern architectures, it achieves a performance between 10% and 50% of the peak one. Although several successful attempts have been made to port selected codes on GPUs, no major HEP code suite has a 'High Performance' implementation. With LHC undergoing a major upgrade and a number of challenging experiments on the drawing board, HEP cannot any longer neglect the less-than-optimal performance of its code and it has to try making the best usage of the hardware. This activity is one of the foci of the SFT group at CERN, which hosts, among others, the Root and Geant4 project. The activity of the experiments is shared and coordinated via a Concurrency Forum, where the experience in optimising HEP code is presented and discussed. Another activity is the Geant-V project, centred on th...

  12. High Performance Commercial Fenestration Framing Systems

    Energy Technology Data Exchange (ETDEWEB)

    Mike Manteghi; Sneh Kumar; Joshua Early; Bhaskar Adusumalli

    2010-01-31

    A major objective of the U.S. Department of Energy is to have a zero energy commercial building by the year 2025. Windows have a major influence on the energy performance of the building envelope as they control over 55% of building energy load, and represent one important area where technologies can be developed to save energy. Aluminum framing systems are used in over 80% of commercial fenestration products (i.e. windows, curtain walls, store fronts, etc.). Aluminum framing systems are often required in commercial buildings because of their inherent good structural properties and long service life, which is required from commercial and architectural frames. At the same time, they are lightweight and durable, requiring very little maintenance, and offer design flexibility. An additional benefit of aluminum framing systems is their relatively low cost and easy manufacturability. Aluminum, being an easily recyclable material, also offers sustainable features. However, from energy efficiency point of view, aluminum frames have lower thermal performance due to the very high thermal conductivity of aluminum. Fenestration systems constructed of aluminum alloys therefore have lower performance in terms of being effective barrier to energy transfer (heat loss or gain). Despite the lower energy performance, aluminum is the choice material for commercial framing systems and dominates the commercial/architectural fenestration market because of the reasons mentioned above. In addition, there is no other cost effective and energy efficient replacement material available to take place of aluminum in the commercial/architectural market. Hence it is imperative to improve the performance of aluminum framing system to improve the energy performance of commercial fenestration system and in turn reduce the energy consumption of commercial building and achieve zero energy building by 2025. The objective of this project was to develop high performance, energy efficient commercial

  13. The Resolved Outflow from 3C 48

    Science.gov (United States)

    Shih, Hsin-Yi; Stockton, Alan

    2014-10-01

    We investigate the properties of the high-velocity outflow driven by the young radio jet of 3C 48, a compact-steep-spectrum source. We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telecope to obtain (1) low-resolution UV and optical spectra and (2) multi-slit medium-resolution spectra of the ionized outflow. With supporting data from ground-based spectrographs, we are able to accurately measure the ratios of diagnostic emission lines such as [O III] λ5007, [O III] λ3727, [N II] λ6548, Hα, Hβ, [Ne V] λ3425, and [Ne III] λ3869. We fit the observed emission-line ratios using a range of ionization models, powered by active galactic nucleus (AGN) radiation and shocks, produced by the MAPPINGS code. We have determined that AGN radiation is likely the dominant ionization source. The outflow's density is estimated to be in the range n = 103-104 cm-3, the mass is ~6 × 106 M ⊙, and the metallicity is likely equal to or higher than solar. Compared with the typical outflows associated with more evolved radio jets, this young outflow is denser, less massive, and more metal rich. Multi-slit observations allow us to construct a two-dimensional velocity map of the outflow that shows a wide range of velocities with distinct velocity components, suggesting a wide-angle clumpy outflow. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO-11574. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Some of the

  14. Linear algebra on high-performance computers

    Energy Technology Data Exchange (ETDEWEB)

    Dongarra, J.J.; Sorensen, D.C.

    1986-01-01

    This paper surveys work recently done at Argonne National Laboratory in an attempt to discover ways to construct numerical software for high-performance computers. The numerical algorithms are taken from several areas of numerical linear algebra. We discuss certain architectural features of advanced-computer architectures that will affect the design of algorithms. The technique of restructuring algorithms in terms of certain modules is reviewed. This technique has proved successful in obtaining a high level of transportability without severe loss of performance on a wide variety of both vector and parallel computers. The module technique is demonstrably effective for dense linear algebra problems. However, in the case of sparse and structured problems it may be difficult to identify general modules that will be as effective. New algorithms have been devised for certain problems in this category. We present examples in three important areas: banded systems, sparse QR factorization, and symmetric eigenvalue problems. 32 refs., 10 figs., 6 tabs.

  15. High-performance liquid chromatography of biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Regnier, F.E.

    1983-10-21

    The ability to separate biological macromolecules with good resolution on liquid chromatographic columns has depended on the development of suitable packing materials. In size exclusion chromatography, molecules are separated by size on the basis of differential permeation of the packing. Ion exchange, hydrophobic interaction (or reversed-phase), and affinity chromatography are all surface-mediated separation methods, although they depend on different retention mechanisms. High-performance liquid chromatographic columns designed for biopolymers offer major advantages over conventional columns in both speed and resolving power. The exponential growth of literature on the high-performance separation of peptides and proteins in particular indicates that the techniques will become the dominant form of column liquid chromatography. 92 refs., 4 figs.

  16. High-Power Wind Turbine: Performance Calculation

    Directory of Open Access Journals (Sweden)

    Goldaev Sergey V.

    2015-01-01

    Full Text Available The paper is devoted to high-power wind turbine performance calculation using Pearson’s chi-squared test the statistical hypothesis on distribution of general totality of air velocities by Weibull-Gnedenko. The distribution parameters are found by numerical solution of transcendental equation with the definition of the gamma function interpolation formula. Values of the operating characteristic of the incomplete gamma function are defined by numerical integration using Weddle’s rule. The comparison of the calculated results using the proposed methodology with those obtained by other authors found significant differences in the values of the sample variance and empirical Pearson. The analysis of the initial and maximum wind speed influence on performance of the high-power wind turbine is done

  17. Evaluation of high-performance computing software

    Energy Technology Data Exchange (ETDEWEB)

    Browne, S.; Dongarra, J. [Univ. of Tennessee, Knoxville, TN (United States); Rowan, T. [Oak Ridge National Lab., TN (United States)

    1996-12-31

    The absence of unbiased and up to date comparative evaluations of high-performance computing software complicates a user`s search for the appropriate software package. The National HPCC Software Exchange (NHSE) is attacking this problem using an approach that includes independent evaluations of software, incorporation of author and user feedback into the evaluations, and Web access to the evaluations. We are applying this approach to the Parallel Tools Library (PTLIB), a new software repository for parallel systems software and tools, and HPC-Netlib, a high performance branch of the Netlib mathematical software repository. Updating the evaluations with feed-back and making it available via the Web helps ensure accuracy and timeliness, and using independent reviewers produces unbiased comparative evaluations difficult to find elsewhere.

  18. Heteroarenes as high performance organic semiconductors.

    Science.gov (United States)

    Jiang, Wei; Li, Yan; Wang, Zhaohui

    2013-07-21

    The design, synthesis, and characterization of new organic semiconductors (OSCs) are important aspects for the development of next-generation optoelectronic devices. Structurally, organic semiconductors based on π-conjugated molecules can be easily modified via rational synthesis to tune multi-level self-assembled structures and discover novel chemical, optical, and electronic properties. Heteroarenes, which contain chalcogens and nitrogens in fused aromatic rings, are being developed as promising semiconducting materials for applications in a variety of electronic devices due to their outstanding optoelectronic properties. We highlight recent approaches toward realizing high performance p-channel field effect transistors based on linear heteroacenes and heteroatom annulated polycyclic aromatics (PAHs) as key functional components. These comprehensive, but carefully orchestrated approaches simultaneously address (i) practical synthesis, (ii) tunable self-assembled packing arrangement as well as (iii) high electronic performance.

  19. High performance cloud auditing and applications

    CERN Document Server

    Choi, Baek-Young; Song, Sejun

    2014-01-01

    This book mainly focuses on cloud security and high performance computing for cloud auditing. The book discusses emerging challenges and techniques developed for high performance semantic cloud auditing, and presents the state of the art in cloud auditing, computing and security techniques with focus on technical aspects and feasibility of auditing issues in federated cloud computing environments.   In summer 2011, the United States Air Force Research Laboratory (AFRL) CyberBAT Cloud Security and Auditing Team initiated the exploration of the cloud security challenges and future cloud auditing research directions that are covered in this book. This work was supported by the United States government funds from the Air Force Office of Scientific Research (AFOSR), the AFOSR Summer Faculty Fellowship Program (SFFP), the Air Force Research Laboratory (AFRL) Visiting Faculty Research Program (VFRP), the National Science Foundation (NSF) and the National Institute of Health (NIH). All chapters were partially suppor...

  20. Monitoring SLAC High Performance UNIX Computing Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lettsome, Annette K.; /Bethune-Cookman Coll. /SLAC

    2005-12-15

    Knowledge of the effectiveness and efficiency of computers is important when working with high performance systems. The monitoring of such systems is advantageous in order to foresee possible misfortunes or system failures. Ganglia is a software system designed for high performance computing systems to retrieve specific monitoring information. An alternative storage facility for Ganglia's collected data is needed since its default storage system, the round-robin database (RRD), struggles with data integrity. The creation of a script-driven MySQL database solves this dilemma. This paper describes the process took in the creation and implementation of the MySQL database for use by Ganglia. Comparisons between data storage by both databases are made using gnuplot and Ganglia's real-time graphical user interface.

  1. Toward a theory of high performance.

    Science.gov (United States)

    Kirby, Julia

    2005-01-01

    What does it mean to be a high-performance company? The process of measuring relative performance across industries and eras, declaring top performers, and finding the common drivers of their success is such a difficult one that it might seem a fool's errand to attempt. In fact, no one did for the first thousand or so years of business history. The question didn't even occur to many scholars until Tom Peters and Bob Waterman released In Search of Excellence in 1982. Twenty-three years later, we've witnessed several more attempts--and, just maybe, we're getting closer to answers. In this reported piece, HBR senior editor Julia Kirby explores why it's so difficult to study high performance and how various research efforts--including those from John Kotter and Jim Heskett; Jim Collins and Jerry Porras; Bill Joyce, Nitin Nohria, and Bruce Roberson; and several others outlined in a summary chart-have attacked the problem. The challenge starts with deciding which companies to study closely. Are the stars the ones with the highest market caps, the ones with the greatest sales growth, or simply the ones that remain standing at the end of the game? (And when's the end of the game?) Each major study differs in how it defines success, which companies it therefore declares to be worthy of emulation, and the patterns of activity and attitude it finds in common among them. Yet, Kirby concludes, as each study's method incrementally solves problems others have faced, we are progressing toward a consensus theory of high performance.

  2. High performance forward swept wing aircraft

    Science.gov (United States)

    Koenig, David G. (Inventor); Aoyagi, Kiyoshi (Inventor); Dudley, Michael R. (Inventor); Schmidt, Susan B. (Inventor)

    1988-01-01

    A high performance aircraft capable of subsonic, transonic and supersonic speeds employs a forward swept wing planform and at least one first and second solution ejector located on the inboard section of the wing. A high degree of flow control on the inboard sections of the wing is achieved along with improved maneuverability and control of pitch, roll and yaw. Lift loss is delayed to higher angles of attack than in conventional aircraft. In one embodiment the ejectors may be advantageously positioned spanwise on the wing while the ductwork is kept to a minimum.

  3. Playa: High-Performance Programmable Linear Algebra

    Directory of Open Access Journals (Sweden)

    Victoria E. Howle

    2012-01-01

    Full Text Available This paper introduces Playa, a high-level user interface layer for composing algorithms for complex multiphysics problems out of objects from other Trilinos packages. Among other features, Playa provides very high-performance overloaded operators implemented through an expression template mechanism. In this paper, we give an overview of the central Playa objects from a user's perspective, show application to a sequence of increasingly complex solver algorithms, provide timing results for Playa's overloaded operators and other functions, and briefly survey some of the implementation issues involved.

  4. Multifrequency observations of extended radio galaxies V - 3C 31, 3C 33.1, 3C 35, 3C 66B, 3C 129, 3C 130, 3C 223, 3C 310, 3C 390.3 and 4C 48.29

    Science.gov (United States)

    van Breugel, W.; Jagers, W.

    1982-08-01

    A sample of 3C radio sources of large angular size has been observed in total and polarized intensity at several wavelengths with the Westerbork Synthesis Radio Telescope. The sources were selected such that their largest angular size was greater than about 200 arcsec and their declination greater than about 25 degrees. Some additional sources with radio jets or peculiar morphology were also included. The name of each source, its structural type classification, wavelength of observation, and data references are given.

  5. High-Performance Liquid Chromatography: An Overview

    OpenAIRE

    Tandia N; Singh SK1; Kumar N; Singh S

    2013-01-01

    Chromatography is considered extremely powerful separation technique for variety of samples. Thecommon feature of all these techniques is that the different components in a sample mixture aredistributed between two phases, one of which remains stationary while the other the mobile phase, runsthrough the interstices or over the surface of the fixed phase. The movement of the mobile phase resultsin differential migration of the sample components. High performance thin layer chromatography is an...

  6. High performance microsystem packaging: A perspective

    Energy Technology Data Exchange (ETDEWEB)

    Romig, A.D. Jr.; Dressendorfer, P.V.; Palmer, D.W.

    1997-10-01

    The second silicon revolution will be based on intelligent, integrated microsystems where multiple technologies (such as analog, digital, memory, sensor, micro-electro-mechanical, and communication devices) are integrated onto a single chip or within a multichip module. A necessary element for such systems is cost-effective, high-performance packaging. This paper examines many of the issues associated with the packaging of integrated microsystems, with an emphasis on the areas of packaging design, manufacturability, and reliability.

  7. Domain Decomposition Based High Performance Parallel Computing

    CERN Document Server

    Raju, Mandhapati P

    2009-01-01

    The study deals with the parallelization of finite element based Navier-Stokes codes using domain decomposition and state-ofart sparse direct solvers. There has been significant improvement in the performance of sparse direct solvers. Parallel sparse direct solvers are not found to exhibit good scalability. Hence, the parallelization of sparse direct solvers is done using domain decomposition techniques. A highly efficient sparse direct solver PARDISO is used in this study. The scalability of both Newton and modified Newton algorithms are tested.

  8. Optics of high-performance electron microscopes*

    OpenAIRE

    H H Rose

    2016-01-01

    During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by...

  9. High performance pattern matching on heterogeneous platform.

    Science.gov (United States)

    Soroushnia, Shima; Daneshtalab, Masoud; Plosila, Juha; Pahikkala, Tapio; Liljeberg, Pasi

    2014-10-23

    Pattern discovery is one of the fundamental tasks in bioinformatics and pattern recognition is a powerful technique for searching sequence patterns in the biological sequence databases. Fast and high performance algorithms are highly demanded in many applications in bioinformatics and computational molecular biology since the significant increase in the number of DNA and protein sequences expand the need for raising the performance of pattern matching algorithms. For this purpose, heterogeneous architectures can be a good choice due to their potential for high performance and energy efficiency. In this paper we present an efficient implementation of Aho-Corasick (AC) which is a well known exact pattern matching algorithm with linear complexity, and Parallel Failureless Aho-Corasick (PFAC) algorithm which is the massively parallelized version of AC algorithm without failure transitions, on a heterogeneous CPU/GPU architecture. We progressively redesigned the algorithms and data structures to fit on the GPU architecture. Our results on different protein sequence data sets show that the new implementation runs 15 times faster compared to the original implementation of the PFAC algorithm.

  10. Computational Biology and High Performance Computing 2000

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Horst D.; Zorn, Manfred D.; Spengler, Sylvia J.; Shoichet, Brian K.; Stewart, Craig; Dubchak, Inna L.; Arkin, Adam P.

    2000-10-19

    The pace of extraordinary advances in molecular biology has accelerated in the past decade due in large part to discoveries coming from genome projects on human and model organisms. The advances in the genome project so far, happening well ahead of schedule and under budget, have exceeded any dreams by its protagonists, let alone formal expectations. Biologists expect the next phase of the genome project to be even more startling in terms of dramatic breakthroughs in our understanding of human biology, the biology of health and of disease. Only today can biologists begin to envision the necessary experimental, computational and theoretical steps necessary to exploit genome sequence information for its medical impact, its contribution to biotechnology and economic competitiveness, and its ultimate contribution to environmental quality. High performance computing has become one of the critical enabling technologies, which will help to translate this vision of future advances in biology into reality. Biologists are increasingly becoming aware of the potential of high performance computing. The goal of this tutorial is to introduce the exciting new developments in computational biology and genomics to the high performance computing community.

  11. High performance computing and communications panel report

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    In FY92, a presidential initiative entitled High Performance Computing and Communications (HPCC) was launched, aimed at securing U.S. preeminence in high performance computing and related communication technologies. The stated goal of the initiative is threefold: extend U.S. technological leadership in high performance computing and computer communications; provide wide dissemination and application of the technologies; and spur gains in U.S. productivity and industrial competitiveness, all within the context of the mission needs of federal agencies. Because of the importance of the HPCC program to the national well-being, especially its potential implication for industrial competitiveness, the Assistant to the President for Science and Technology has asked that the President's Council of Advisors in Science and Technology (PCAST) establish a panel to advise PCAST on the strengths and weaknesses of the HPCC program. The report presents a program analysis based on strategy, balance, management, and vision. Both constructive recommendations for program improvement and positive reinforcement of successful program elements are contained within the report.

  12. High Performance Database Management for Earth Sciences

    Science.gov (United States)

    Rishe, Naphtali; Barton, David; Urban, Frank; Chekmasov, Maxim; Martinez, Maria; Alvarez, Elms; Gutierrez, Martha; Pardo, Philippe

    1998-01-01

    The High Performance Database Research Center at Florida International University is completing the development of a highly parallel database system based on the semantic/object-oriented approach. This system provides exceptional usability and flexibility. It allows shorter application design and programming cycles and gives the user control via an intuitive information structure. It empowers the end-user to pose complex ad hoc decision support queries. Superior efficiency is provided through a high level of optimization, which is transparent to the user. Manifold reduction in storage size is allowed for many applications. This system allows for operability via internet browsers. The system will be used for the NASA Applications Center program to store remote sensing data, as well as for Earth Science applications.

  13. [High-performance society and doping].

    Science.gov (United States)

    Gallien, C L

    2002-09-01

    Doping is not limited to high-level athletes. Likewise it is not limited to the field of sports activities. The doping phenomenon observed in sports actually reveals an underlying question concerning the notion of sports itself, and more widely, the society's conception of sports. In a high-performance society, which is also a high-risk society, doping behavior is observed in a large number of persons who may or may not participate in sports activities. The motivation is the search for individual success or profit. The fight against doping must therefore focus on individual responsibility and prevention in order to preserve athlete's health and maintain the ethical and educational value of sports activities.

  14. Hybrid ventilation systems and high performance buildings

    Energy Technology Data Exchange (ETDEWEB)

    Utzinger, D.M. [Wisconsin Univ., Milwaukee, WI (United States). School of Architecture and Urban Planning

    2009-07-01

    This paper described hybrid ventilation design strategies and their impact on 3 high performance buildings located in southern Wisconsin. The Hybrid ventilation systems combined occupant controlled natural ventilation with mechanical ventilation systems. Natural ventilation was shown to provide adequate ventilation when appropriately designed. Proper control integration of natural ventilation into hybrid systems was shown to reduce energy consumption in high performance buildings. This paper also described the lessons learned from the 3 buildings. The author served as energy consultant on all three projects and had the responsibility of designing and integrating the natural ventilation systems into the HVAC control strategy. A post occupancy evaluation of building energy performance has provided learning material for architecture students. The 3 buildings included the Schlitz Audubon Nature Center completed in 2003; the Urban Ecology Center completed in 2004; and the Aldo Leopold Legacy Center completed in 2007. This paper included the size, measured energy utilization intensity and percentage of energy supplied by renewable solar power and bio-fuels on site for each building. 6 refs., 2 tabs., 6 figs.

  15. Automatic Energy Schemes for High Performance Applications

    Energy Technology Data Exchange (ETDEWEB)

    Sundriyal, Vaibhav [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    Although high-performance computing traditionally focuses on the efficient execution of large-scale applications, both energy and power have become critical concerns when approaching exascale. Drastic increases in the power consumption of supercomputers affect significantly their operating costs and failure rates. In modern microprocessor architectures, equipped with dynamic voltage and frequency scaling (DVFS) and CPU clock modulation (throttling), the power consumption may be controlled in software. Additionally, network interconnect, such as Infiniband, may be exploited to maximize energy savings while the application performance loss and frequency switching overheads must be carefully balanced. This work first studies two important collective communication operations, all-to-all and allgather and proposes energy saving strategies on the per-call basis. Next, it targets point-to-point communications to group them into phases and apply frequency scaling to them to save energy by exploiting the architectural and communication stalls. Finally, it proposes an automatic runtime system which combines both collective and point-to-point communications into phases, and applies throttling to them apart from DVFS to maximize energy savings. The experimental results are presented for NAS parallel benchmark problems as well as for the realistic parallel electronic structure calculations performed by the widely used quantum chemistry package GAMESS. Close to the maximum energy savings were obtained with a substantially low performance loss on the given platform.

  16. Building Trust in High-Performing Teams

    Directory of Open Access Journals (Sweden)

    Aki Soudunsaari

    2012-06-01

    Full Text Available Facilitation of growth is more about good, trustworthy contacts than capital. Trust is a driving force for business creation, and to create a global business you need to build a team that is capable of meeting the challenge. Trust is a key factor in team building and a needed enabler for cooperation. In general, trust building is a slow process, but it can be accelerated with open interaction and good communication skills. The fast-growing and ever-changing nature of global business sets demands for cooperation and team building, especially for startup companies. Trust building needs personal knowledge and regular face-to-face interaction, but it also requires empathy, respect, and genuine listening. Trust increases communication, and rich and open communication is essential for the building of high-performing teams. Other building materials are a shared vision, clear roles and responsibilities, willingness for cooperation, and supporting and encouraging leadership. This study focuses on trust in high-performing teams. It asks whether it is possible to manage trust and which tools and operation models should be used to speed up the building of trust. In this article, preliminary results from the authors’ research are presented to highlight the importance of sharing critical information and having a high level of communication through constant interaction.

  17. High-performance computing in seismology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The scientific, technical, and economic importance of the issues discussed here presents a clear agenda for future research in computational seismology. In this way these problems will drive advances in high-performance computing in the field of seismology. There is a broad community that will benefit from this work, including the petroleum industry, research geophysicists, engineers concerned with seismic hazard mitigation, and governments charged with enforcing a comprehensive test ban treaty. These advances may also lead to new applications for seismological research. The recent application of high-resolution seismic imaging of the shallow subsurface for the environmental remediation industry is an example of this activity. This report makes the following recommendations: (1) focused efforts to develop validated documented software for seismological computations should be supported, with special emphasis on scalable algorithms for parallel processors; (2) the education of seismologists in high-performance computing technologies and methodologies should be improved; (3) collaborations between seismologists and computational scientists and engineers should be increased; (4) the infrastructure for archiving, disseminating, and processing large volumes of seismological data should be improved.

  18. High performance robotic traverse of desert terrain.

    Energy Technology Data Exchange (ETDEWEB)

    Whittaker, William (Carnegie Mellon University, Pittsburgh, PA)

    2004-09-01

    This report presents tentative innovations to enable unmanned vehicle guidance for a class of off-road traverse at sustained speeds greater than 30 miles per hour. Analyses and field trials suggest that even greater navigation speeds might be achieved. The performance calls for innovation in mapping, perception, planning and inertial-referenced stabilization of components, hosted aboard capable locomotion. The innovations are motivated by the challenge of autonomous ground vehicle traverse of 250 miles of desert terrain in less than 10 hours, averaging 30 miles per hour. GPS coverage is assumed to be available with localized blackouts. Terrain and vegetation are assumed to be akin to that of the Mojave Desert. This terrain is interlaced with networks of unimproved roads and trails, which are a key to achieving the high performance mapping, planning and navigation that is presented here.

  19. Intel Xeon Phi coprocessor high performance programming

    CERN Document Server

    Jeffers, James

    2013-01-01

    Authors Jim Jeffers and James Reinders spent two years helping educate customers about the prototype and pre-production hardware before Intel introduced the first Intel Xeon Phi coprocessor. They have distilled their own experiences coupled with insights from many expert customers, Intel Field Engineers, Application Engineers and Technical Consulting Engineers, to create this authoritative first book on the essentials of programming for this new architecture and these new products. This book is useful even before you ever touch a system with an Intel Xeon Phi coprocessor. To ensure that your applications run at maximum efficiency, the authors emphasize key techniques for programming any modern parallel computing system whether based on Intel Xeon processors, Intel Xeon Phi coprocessors, or other high performance microprocessors. Applying these techniques will generally increase your program performance on any system, and better prepare you for Intel Xeon Phi coprocessors and the Intel MIC architecture. It off...

  20. GA binding protein augments autophagy via transcriptional activation of BECN1-PIK3C3 complex genes.

    Science.gov (United States)

    Zhu, Wan; Swaminathan, Gayathri; Plowey, Edward D

    2014-09-01

    Macroautophagy is a vesicular catabolic trafficking pathway that is thought to protect cells from diverse stressors and to promote longevity. Recent studies have revealed that transcription factors play important roles in the regulation of autophagy. In this study, we have identified GA binding protein (GABP) as a transcriptional regulator of the combinatorial expression of BECN1-PIK3C3 complex genes involved in autophagosome initiation. We performed bioinformatics analyses that demonstrated highly conserved putative GABP sites in genes that encode BECN1/Beclin 1, several BECN1 interacting proteins, and downstream autophagy proteins including the ATG12-ATG5-ATG16L1 complex. We demonstrate that GABP binds to the promoter regions of BECN1-PIK3C3 complex genes and activates their transcriptional activities. Knockdown of GABP reduced BECN1-PIK3C3 complex transcripts, BECN1-PIK3C3 complex protein levels and autophagy in cultured cells. Conversely, overexpression of GABP increased autophagy. Nutrient starvation increased GABP-dependent transcriptional activity of BECN1-PIK3C3 complex gene promoters and increased the recruitment of GABP to the BECN1 promoter. Our data reveal a novel function of GABP in the regulation of autophagy via transcriptional activation of the BECN1-PIK3C3 complex.

  1. High Performance Network Security Using NIDS Approach

    Directory of Open Access Journals (Sweden)

    Sutapa Sarkar

    2014-06-01

    Full Text Available Ever increasing demand of good quality communication relies heavily on Network Intrusion Detection System (NIDS. Intrusion detection for network security demands high performance. This paper gives a description of the available approaches for a network intrusion detection system in both software and hardware implementation. This paper gives a description of the structure of Snort rule set which is a very popular software signature and anomaly based Intrusion Detection and prevention system. This paper also discusses the merit of FPGA devices to be used in network intrusion detection system implementation and the approaches used in hardware implementation of NIDS.

  2. High Performance Single Nanowire Tunnel Diodes

    DEFF Research Database (Denmark)

    Wallentin, Jesper; Persson, Johan Mikael; Wagner, Jakob Birkedal;

    for planar growth, many new materials combinations can be grown in a single NW. This opens up exciting opportunities for NW-based high-performance solar cells, where previously inaccessible materials combinations can now be chosen to match the solar spectrum. A key component of a multi-junction solar cell......Semiconductor nanowires (NWs) have emerged as a promising technology for future electronic and optoelectronic devices. Epitaxial growth of III-V materials on Si substrates have been demonstrated, allowing for low-cost production. As the lattice matching requirements are much less strict than...

  3. Applications of modern high performance networks

    CERN Document Server

    Zubairi, Junaid Ahmed

    2009-01-01

    This Ebook presents state-of-the-art solutions in applications of modern high performance networks. The topics covered in this Ebook include mobile ad-hoc networks, clusters for distance computing, clustering technologies and deployment, emerging wireless sensor network technologies, ultra wideband wireless sensor networks, and smart agriculture with sensor networks. This Ebook stands out from others in the field by bringing together the most diverse applications of networks under one title. It is aimed at academicians, students and working professionals in hospitals, agriculture, government,

  4. High Performance Piezoelectric Actuated Gimbal (HIERAX)

    Energy Technology Data Exchange (ETDEWEB)

    Charles Tschaggeny; Warren Jones; Eberhard Bamberg

    2007-04-01

    This paper presents a 3-axis gimbal whose three rotational axes are actuated by a novel drive system: linear piezoelectric motors whose linear output is converted to rotation by using drive disks. Advantages of this technology are: fast response, high accelerations, dither-free actuation and backlash-free positioning. The gimbal was developed to house a laser range finder for the purpose of tracking and guiding unmanned aerial vehicles during landing maneuvers. The tilt axis was built and the test results indicate excellent performance that meets design specifications.

  5. Initial performance of the High Speed Photometer

    Science.gov (United States)

    Richards, Evan; Percival, Jeff; Nelson, Matt; Hatter, ED; Fitch, John; White, Rick

    1991-01-01

    The Hubble Space Telescope High Speed Photometer has four image dissector tubes, two with UV sensitive photocathodes, two sensitive to the near UV and to visual light, and a single red sensitive photomultiplier tube. The HSP is capable of photometric measurements from 1200 to 7500 A with time resolution of 11 microseconds and has no moving parts. An initial analysis of the on-orbit engineering performance of the HSP is presented with changes in operating procedures resulting from the primary mirror spherical aberration and experience gained during the verification period.

  6. Porous Core-Shell Fe3C Embedded N-doped Carbon Nanofibers as an Effective Electrocatalysts for Oxygen Reduction Reaction.

    Science.gov (United States)

    Ren, Guangyuan; Lu, Xianyong; Li, Yunan; Zhu, Ying; Dai, Liming; Jiang, Lei

    2016-02-17

    The development of nonprecious-metal-based electrocatalysts with high oxygen reduction reaction (ORR) activity, low cost, and good durability in both alkaline and acidic media is very important for application of full cells. Herein, we developed a facile and economical strategy to obtain porous core-shell Fe3C embedded nitrogen-doped carbon nanofibers (Fe3C@NCNF-X, where X denotes pyrolysis temperature) by electrospinning of polyvinylidene fluoride (PVDF) and FeCl3 mixture, chemical vapor phase polymerization of pyrrole, and followed by pyrolysis of composite nanofibers at high temperatures. Note that the FeCl3 and polypyrrole acts as precursor for Fe3C core and N-doped carbon shell, respectively. Moreover, PVDF not only plays a role as carbon resources, but also provides porous structures due to hydrogen fluoride exposure originated from thermal decomposition of PVDF. The resultant Fe3C@NCNF-X catalysts, particularly Fe3C@NCNF-900, showed efficient electrocatalytic performance for ORR in both alkaline and acidic solutions, which are attributed to the synergistic effect between Fe3C and N-doped carbon as catalytic active sites, and carbon shell protects Fe3C from leaching out. In addition, the Fe3C@NCNF-X catalyst displayed a better long-term stability, free from methanol crossover and CO-poisoning effects than those of Pt/C, which is of great significance for the design and development of advanced electrocatalysts based on nonprecious metals.

  7. High performance visual display for HENP detectors

    CERN Document Server

    McGuigan, M; Spiletic, J; Fine, V; Nevski, P

    2001-01-01

    A high end visual display for High Energy Nuclear Physics (HENP) detectors is necessary because of the sheer size and complexity of the detector. For BNL this display will be of special interest because of STAR and ATLAS. To load, rotate, query, and debug simulation code with a modern detector simply takes too long even on a powerful work station. To visualize the HENP detectors with maximal performance we have developed software with the following characteristics. We develop a visual display of HENP detectors on BNL multiprocessor visualization server at multiple level of detail. We work with general and generic detector framework consistent with ROOT, GAUDI etc, to avoid conflicting with the many graphic development groups associated with specific detectors like STAR and ATLAS. We develop advanced OpenGL features such as transparency and polarized stereoscopy. We enable collaborative viewing of detector and events by directly running the analysis in BNL stereoscopic theatre. We construct enhanced interactiv...

  8. Parallel Algebraic Multigrid Methods - High Performance Preconditioners

    Energy Technology Data Exchange (ETDEWEB)

    Yang, U M

    2004-11-11

    The development of high performance, massively parallel computers and the increasing demands of computationally challenging applications have necessitated the development of scalable solvers and preconditioners. One of the most effective ways to achieve scalability is the use of multigrid or multilevel techniques. Algebraic multigrid (AMG) is a very efficient algorithm for solving large problems on unstructured grids. While much of it can be parallelized in a straightforward way, some components of the classical algorithm, particularly the coarsening process and some of the most efficient smoothers, are highly sequential, and require new parallel approaches. This chapter presents the basic principles of AMG and gives an overview of various parallel implementations of AMG, including descriptions of parallel coarsening schemes and smoothers, some numerical results as well as references to existing software packages.

  9. The multiwavelength variability of 3C 273

    CERN Document Server

    Soldi, S; Paltani, S; Aller, H D; Aller, M F; Bürki, G; Chernyakova, M; Lähteenmäki, A; McHardy, I M; Robson, E I; Staubert, R; Tornikoski, M; Walter, R; Courvoisier, T J -L

    2008-01-01

    We present an update of 3C 273's database hosted by the ISDC, completed with data from radio to gamma-ray observations over the last 10 years. We use this large data set to study the multiwavelength properties of this quasar,especially focussing on its variability behaviour. We study the amplitude of the variations and the maximum variability time scales across the broad-band spectrum and correlate the light curves in different bands, specifically with the X-rays, to search for possible connections between the emission at different energies. 3C 273 shows variability at all frequencies, with amplitudes and time scales strongly depending on the energy and being the signatures of the different emission mechanisms. The variability properties of the X-ray band imply the presence of either two separate components (possibly a Seyfert-like and a blazar-like) or at least two parameters with distinct timing properties to account for the X-ray emission below and above ~20 keV. The dominant hard X-ray emission is most pr...

  10. Development of a High Performance Spacer Grid

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kee Nam; Song, K. N.; Yoon, K. H. (and others)

    2007-03-15

    A spacer grid in a LWR fuel assembly is a key structural component to support fuel rods and to enhance the heat transfer from the fuel rod to the coolant. In this research, the main research items are the development of inherent and high performance spacer grid shapes, the establishment of mechanical/structural analysis and test technology, and the set-up of basic test facilities for the spacer grid. The main research areas and results are as follows. 1. 18 different spacer grid candidates have been invented and applied for domestic and US patents. Among the candidates 16 are chosen from the patent. 2. Two kinds of spacer grids are finally selected for the advanced LWR fuel after detailed performance tests on the candidates and commercial spacer grids from a mechanical/structural point of view. According to the test results the features of the selected spacer grids are better than those of the commercial spacer grids. 3. Four kinds of basic test facilities are set up and the relevant test technologies are established. 4. Mechanical/structural analysis models and technology for spacer grid performance are developed and the analysis results are compared with the test results to enhance the reliability of the models.

  11. Low cost high performance uncertainty quantification

    KAUST Repository

    Bekas, C.

    2009-01-01

    Uncertainty quantification in risk analysis has become a key application. In this context, computing the diagonal of inverse covariance matrices is of paramount importance. Standard techniques, that employ matrix factorizations, incur a cubic cost which quickly becomes intractable with the current explosion of data sizes. In this work we reduce this complexity to quadratic with the synergy of two algorithms that gracefully complement each other and lead to a radically different approach. First, we turned to stochastic estimation of the diagonal. This allowed us to cast the problem as a linear system with a relatively small number of multiple right hand sides. Second, for this linear system we developed a novel, mixed precision, iterative refinement scheme, which uses iterative solvers instead of matrix factorizations. We demonstrate that the new framework not only achieves the much needed quadratic cost but in addition offers excellent opportunities for scaling at massively parallel environments. We based our implementation on BLAS 3 kernels that ensure very high processor performance. We achieved a peak performance of 730 TFlops on 72 BG/P racks, with a sustained performance 73% of theoretical peak. We stress that the techniques presented in this work are quite general and applicable to several other important applications. Copyright © 2009 ACM.

  12. Performance of the CMS High Level Trigger

    CERN Document Server

    Perrotta, Andrea

    2015-01-01

    The CMS experiment has been designed with a 2-level trigger system. The first level is implemented using custom-designed electronics. The second level is the so-called High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. For Run II of the Large Hadron Collider, the increases in center-of-mass energy and luminosity will raise the event rate to a level challenging for the HLT algorithms. The increase in the number of interactions per bunch crossing, on average 25 in 2012, and expected to be around 40 in Run II, will be an additional complication. We present here the expected performance of the main triggers that will be used during the 2015 data taking campaign, paying particular attention to the new approaches that have been developed to cope with the challenges of the new run. This includes improvements in HLT electron and photon reconstruction as well as better performing muon triggers. We will also present the performance of the improved trac...

  13. High-Performance Broadcasting Algorithms on Cluster

    Institute of Scientific and Technical Information of China (English)

    舒继武; 魏英霞; 王鼎兴

    2004-01-01

    In many clusters connected by high-speed communication networks, the exact structure of the underlying communication network and the latency difference between different sending and receiving pairs may be ignored when they broadcast, such as in the approach adopted by the broadcasting method in MPICH,a widely used MPI implementation. However, the underlying network cluster topologies are becoming more and more complicated and the performance of traditional broadcasting algorithms, such as MPICH's MPI_Bcast, is far from good. This paper analyzed the impact of communication latencies and the underlying topologies on the performance of broadcasting algorithms for multilevel clusters. A multilevel model was developed for broadcasting in clusters with complicated topologies, which divides the cluster topology into many levels based on the underlying topology. The multilevel model was used to develop a new broadcast algorithm,MLM broadcast-2 (MLMB-2), that adapts to a wide range of clusters. Comparison of the performance of the counterpart MPI operation MPI_Bcast and MLMB-2 shows that MLMB-2 outperforms MPl_Bcast by decreasing the broadcast running time by 60%-90%.

  14. High-performance laboratories and cleanrooms

    Energy Technology Data Exchange (ETDEWEB)

    Tschudi, William; Sartor, Dale; Mills, Evan; Xu, Tengfang

    2002-07-01

    The California Energy Commission sponsored this roadmap to guide energy efficiency research and deployment for high performance cleanrooms and laboratories. Industries and institutions utilizing these building types (termed high-tech buildings) have played an important part in the vitality of the California economy. This roadmap's key objective to present a multi-year agenda to prioritize and coordinate research efforts. It also addresses delivery mechanisms to get the research products into the market. Because of the importance to the California economy, it is appropriate and important for California to take the lead in assessing the energy efficiency research needs, opportunities, and priorities for this market. In addition to the importance to California's economy, energy demand for this market segment is large and growing (estimated at 9400 GWH for 1996, Mills et al. 1996). With their 24hr. continuous operation, high tech facilities are a major contributor to the peak electrical demand. Laboratories and cleanrooms constitute the high tech building market, and although each building type has its unique features, they are similar in that they are extremely energy intensive, involve special environmental considerations, have very high ventilation requirements, and are subject to regulations--primarily safety driven--that tend to have adverse energy implications. High-tech buildings have largely been overlooked in past energy efficiency research. Many industries and institutions utilize laboratories and cleanrooms. As illustrated, there are many industries operating cleanrooms in California. These include semiconductor manufacturing, semiconductor suppliers, pharmaceutical, biotechnology, disk drive manufacturing, flat panel displays, automotive, aerospace, food, hospitals, medical devices, universities, and federal research facilities.

  15. SISYPHUS: A high performance seismic inversion factory

    Science.gov (United States)

    Gokhberg, Alexey; Simutė, Saulė; Boehm, Christian; Fichtner, Andreas

    2016-04-01

    In the recent years the massively parallel high performance computers became the standard instruments for solving the forward and inverse problems in seismology. The respective software packages dedicated to forward and inverse waveform modelling specially designed for such computers (SPECFEM3D, SES3D) became mature and widely available. These packages achieve significant computational performance and provide researchers with an opportunity to solve problems of bigger size at higher resolution within a shorter time. However, a typical seismic inversion process contains various activities that are beyond the common solver functionality. They include management of information on seismic events and stations, 3D models, observed and synthetic seismograms, pre-processing of the observed signals, computation of misfits and adjoint sources, minimization of misfits, and process workflow management. These activities are time consuming, seldom sufficiently automated, and therefore represent a bottleneck that can substantially offset performance benefits provided by even the most powerful modern supercomputers. Furthermore, a typical system architecture of modern supercomputing platforms is oriented towards the maximum computational performance and provides limited standard facilities for automation of the supporting activities. We present a prototype solution that automates all aspects of the seismic inversion process and is tuned for the modern massively parallel high performance computing systems. We address several major aspects of the solution architecture, which include (1) design of an inversion state database for tracing all relevant aspects of the entire solution process, (2) design of an extensible workflow management framework, (3) integration with wave propagation solvers, (4) integration with optimization packages, (5) computation of misfits and adjoint sources, and (6) process monitoring. The inversion state database represents a hierarchical structure with

  16. Multi-Frequency VLBA Studies of the Parsec-Scale Jets in 3C 66A and 3C 66B

    Indian Academy of Sciences (India)

    G.-Y. Zhao; Y.-J. Chen; Z.-Q. Shen; H. Sudou; S. Iguchi; F. Gao; Y. Murata; Y. Taniguchi

    2014-09-01

    We report multi-frequency VLBA phase-referencing observation results of 3C 66A and 3C 66B, including high resolution maps and relative position measurements. The resulting images show similar morphology with that presented in previous works. We find core shift variations in both sources, indicating some physical condition changes in the jets.

  17. HST Polarimetry of the 3C 273 Jet

    Science.gov (United States)

    Clautice, Devon; Perlman, Eric S.; Sparks, William B.; Biretta, John A.; O'Dea, Christopher P.; Baum, Stefi Alison; Cheung, Chi C.; Birkinshaw, Mark; Worrall, Diana M.; Martel, Andre; Urry, C. Megan; Stawarz, Lukasz; Coppi, Paolo S.; Uchiyama, Yasunobu; Cara, Mihai; Meisenheimer, Klaus; Begelman, Mitchell C.

    2017-01-01

    We present preliminary results using HST polarimetry of the jet of 3C 273. Polarization is a critical parameter for understanding jet flows, and has proven essential in characterizing the physics of FR I jets; high-quality HST polarimetry has been done for just two other FR II jets previously. Our recent work on two quasar jets, where we measured high optical polarization in the brightest X-ray knots, has favored the synchrotron emission model over the alternative IC/CMB model for their optical to X-ray emission. These new observations of 3C 273 allow for the determination of the magnetic field structure and confirmation of which emission mechanisms are operating to create its optical to X-ray emission, and will allow us to greatly advance modeling efforts for this jet and nail down its kinetic power, a key unknown parameter for understanding quasars and their cosmological effects.

  18. PREFACE: High Performance Computing Symposium 2011

    Science.gov (United States)

    Talon, Suzanne; Mousseau, Normand; Peslherbe, Gilles; Bertrand, François; Gauthier, Pierre; Kadem, Lyes; Moitessier, Nicolas; Rouleau, Guy; Wittig, Rod

    2012-02-01

    HPCS (High Performance Computing Symposium) is a multidisciplinary conference that focuses on research involving High Performance Computing and its application. Attended by Canadian and international experts and renowned researchers in the sciences, all areas of engineering, the applied sciences, medicine and life sciences, mathematics, the humanities and social sciences, it is Canada's pre-eminent forum for HPC. The 25th edition was held in Montréal, at the Université du Québec à Montréal, from 15-17 June and focused on HPC in Medical Science. The conference was preceded by tutorials held at Concordia University, where 56 participants learned about HPC best practices, GPU computing, parallel computing, debugging and a number of high-level languages. 274 participants from six countries attended the main conference, which involved 11 invited and 37 contributed oral presentations, 33 posters, and an exhibit hall with 16 booths from our sponsors. The work that follows is a collection of papers presented at the conference covering HPC topics ranging from computer science to bioinformatics. They are divided here into four sections: HPC in Engineering, Physics and Materials Science, HPC in Medical Science, HPC Enabling to Explore our World and New Algorithms for HPC. We would once more like to thank the participants and invited speakers, the members of the Scientific Committee, the referees who spent time reviewing the papers and our invaluable sponsors. To hear the invited talks and learn about 25 years of HPC development in Canada visit the Symposium website: http://2011.hpcs.ca/lang/en/conference/keynote-speakers/ Enjoy the excellent papers that follow, and we look forward to seeing you in Vancouver for HPCS 2012! Gilles Peslherbe Chair of the Scientific Committee Normand Mousseau Co-Chair of HPCS 2011 Suzanne Talon Chair of the Organizing Committee UQAM Sponsors The PDF also contains photographs from the conference banquet.

  19. Scalable resource management in high performance computers.

    Energy Technology Data Exchange (ETDEWEB)

    Frachtenberg, E. (Eitan); Petrini, F. (Fabrizio); Fernandez Peinador, J. (Juan); Coll, S. (Salvador)

    2002-01-01

    Clusters of workstations have emerged as an important platform for building cost-effective, scalable and highly-available computers. Although many hardware solutions are available today, the largest challenge in making large-scale clusters usable lies in the system software. In this paper we present STORM, a resource management tool designed to provide scalability, low overhead and the flexibility necessary to efficiently support and analyze a wide range of job scheduling algorithms. STORM achieves these feats by closely integrating the management daemons with the low-level features that are common in state-of-the-art high-performance system area networks. The architecture of STORM is based on three main technical innovations. First, a sizable part of the scheduler runs in the thread processor located on the network interface. Second, we use hardware collectives that are highly scalable both for implementing control heartbeats and to distribute the binary of a parallel job in near-constant time, irrespective of job and machine sizes. Third, we use an I/O bypass protocol that allows fast data movements from the file system to the communication buffers in the network interface and vice versa. The experimental results show that STORM can launch a job with a binary of 12MB on a 64 processor/32 node cluster in less than 0.25 sec on an empty network, in less than 0.45 sec when all the processors are busy computing other jobs, and in less than 0.65 sec when the network is flooded with a background traffic. This paper provides experimental and analytical evidence that these results scale to a much larger number of nodes. To the best of our knowledge, STORM is at least two orders of magnitude faster than existing production schedulers in launching jobs, performing resource management tasks and gang scheduling.

  20. High Performance Computing in Science and Engineering '15 : Transactions of the High Performance Computing Center

    CERN Document Server

    Kröner, Dietmar; Resch, Michael

    2016-01-01

    This book presents the state-of-the-art in supercomputer simulation. It includes the latest findings from leading researchers using systems from the High Performance Computing Center Stuttgart (HLRS) in 2015. The reports cover all fields of computational science and engineering ranging from CFD to computational physics and from chemistry to computer science with a special emphasis on industrially relevant applications. Presenting findings of one of Europe’s leading systems, this volume covers a wide variety of applications that deliver a high level of sustained performance. The book covers the main methods in high-performance computing. Its outstanding results in achieving the best performance for production codes are of particular interest for both scientists and engineers. The book comes with a wealth of color illustrations and tables of results.

  1. High-performance phase-field modeling

    KAUST Repository

    Vignal, Philippe

    2015-04-27

    Many processes in engineering and sciences involve the evolution of interfaces. Among the mathematical frameworks developed to model these types of problems, the phase-field method has emerged as a possible solution. Phase-fields nonetheless lead to complex nonlinear, high-order partial differential equations, whose solution poses mathematical and computational challenges. Guaranteeing some of the physical properties of the equations has lead to the development of efficient algorithms and discretizations capable of recovering said properties by construction [2, 5]. This work builds-up on these ideas, and proposes novel discretization strategies that guarantee numerical energy dissipation for both conserved and non-conserved phase-field models. The temporal discretization is based on a novel method which relies on Taylor series and ensures strong energy stability. It is second-order accurate, and can also be rendered linear to speed-up the solution process [4]. The spatial discretization relies on Isogeometric Analysis, a finite element method that possesses the k-refinement technology and enables the generation of high-order, high-continuity basis functions. These basis functions are well suited to handle the high-order operators present in phase-field models. Two-dimensional and three dimensional results of the Allen-Cahn, Cahn-Hilliard, Swift-Hohenberg and phase-field crystal equation will be presented, which corroborate the theoretical findings, and illustrate the robustness of the method. Results related to more challenging examples, namely the Navier-Stokes Cahn-Hilliard and a diusion-reaction Cahn-Hilliard system, will also be presented. The implementation was done in PetIGA and PetIGA-MF, high-performance Isogeometric Analysis frameworks [1, 3], designed to handle non-linear, time-dependent problems.

  2. The structure and emission model of the relativistic jet in the quasar 3C 279 inferred from radio to high-energy gamma-ray observations in 2008-2010

    CERN Document Server

    Hayashida, M; Nalewajko, K; Sikora, M; Wehrle, A E; Ogle, P; Collmar, W; Larsson, S; Fukazawa, Y; Itoh, R; Chiang, J; Stawarz, L; Blandford, R D; Richards, J L; Max-Moerbeck, W; Readhead, A; Buehler, R; Cavazzuti, E; Ciprini, S; Gehrels, N; Reimer, A; Szostek, A; Tanaka, T; Tosti, G; Uchiyama, Y; Kawabata, K S; Kino, M; Sakimoto, K; Sasada, M; Sato, S; Uemura, M; Yamanaka, M; Greiner, J; Kruehler, T; Rossi, A; Macquart, J P; Bock, D C -J; Villata, M; Raiteri, C M; Agudo, I; Aller, H D; Aller, M F; Arkharov, A A; Bach, U; Benitez, E; Berdyugin, A; Blinov, D A; Blumenthal, K; Boettcher, M; Buemi, C S; Carosati, D; Chen, W P; Di Paola, A; Dolci, M; Efimova, N V; Forne, E; Gomez, J L; Gurwell, M A; Heidt, J; Hiriart, D; Jordan, B; Jorstad, S G; Joshi, M; Kimeridze, G; Konstantinova, T S; Kopatskaya, E N; Koptelova, E; Kurtanidze, O M; Lahteenmaki, A; Lamerato, A; Larionov, V M; Larionova, E G; Larionova, L V; Leto, P; Lindfors, E; Marscher, A P; McHardy, I M; Molina, S N; Morozova, D A; Nikolashvili, M G; Nilsson, K; Reinthal, R; Roustazadeh, P; Sakamoto, T; Sigua, L A; Sillanpaa, A; Takalo, L; Tammi, J; Taylor, B; Tornikoski, M; Trigilio, C; Troitsky, I S; Umana, G

    2012-01-01

    We present time-resolved broad-band observations of the quasar 3C 279 obtained from multi-wavelength campaigns conducted during the first two years of the Fermi Gamma-ray Space Telescope mission. While investigating the previously reported gamma-ray/optical flare accompanied by a change in optical polarization, we found that the optical emission appears delayed with respect to the gamma-ray emission by about 10 days. X-ray observations reveal a pair of `isolated' flares separated by ~90 days, with only weak gamma-ray/optical counterparts. The spectral structure measured by Spitzer reveals a synchrotron component peaking in the mid-infrared band with a sharp break at the far-infrared band during the gamma-ray flare, while the peak appears in the mm/sub-mm band in the low state. Selected spectral energy distributions are fitted with leptonic models including Comptonization of external radiation produced in a dusty torus or the broad-line region. Adopting the interpretation of the polarization swing involving pr...

  3. Integrating advanced facades into high performance buildings

    Energy Technology Data Exchange (ETDEWEB)

    Selkowitz, Stephen E.

    2001-05-01

    Glass is a remarkable material but its functionality is significantly enhanced when it is processed or altered to provide added intrinsic capabilities. The overall performance of glass elements in a building can be further enhanced when they are designed to be part of a complete facade system. Finally the facade system delivers the greatest performance to the building owner and occupants when it becomes an essential element of a fully integrated building design. This presentation examines the growing interest in incorporating advanced glazing elements into more comprehensive facade and building systems in a manner that increases comfort, productivity and amenity for occupants, reduces operating costs for building owners, and contributes to improving the health of the planet by reducing overall energy use and negative environmental impacts. We explore the role of glazing systems in dynamic and responsive facades that provide the following functionality: Enhanced sun protection and cooling load control while improving thermal comfort and providing most of the light needed with daylighting; Enhanced air quality and reduced cooling loads using natural ventilation schemes employing the facade as an active air control element; Reduced operating costs by minimizing lighting, cooling and heating energy use by optimizing the daylighting-thermal tradeoffs; Net positive contributions to the energy balance of the building using integrated photovoltaic systems; Improved indoor environments leading to enhanced occupant health, comfort and performance. In addressing these issues facade system solutions must, of course, respect the constraints of latitude, location, solar orientation, acoustics, earthquake and fire safety, etc. Since climate and occupant needs are dynamic variables, in a high performance building the facade solution have the capacity to respond and adapt to these variable exterior conditions and to changing occupant needs. This responsive performance capability

  4. Optics of high-performance electron microscopes.

    Science.gov (United States)

    Rose, H H

    2008-01-01

    During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by multipole fields and to a discussion of the most advanced design that take advantage of these techniques. The theory of electron mirrors is developed and it is shown how this can be used to correct aberrations and to design energy filters. Finally, different types of energy filters are described.

  5. High performance nano-composite technology development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Whung Whoe; Rhee, C. K.; Kim, S. J.; Park, S. D. [KAERI, Taejon (Korea, Republic of); Kim, E. K.; Jung, S. Y.; Ryu, H. J. [KRICT, Taejon (Korea, Republic of); Hwang, S. S.; Kim, J. K.; Hong, S. M. [KIST, Taejon (Korea, Republic of); Chea, Y. B. [KIGAM, Taejon (Korea, Republic of); Choi, C. H.; Kim, S. D. [ATS, Taejon (Korea, Republic of); Cho, B. G.; Lee, S. H. [HGREC, Taejon (Korea, Republic of)

    1999-06-15

    The trend of new material development are being to carried out not only high performance but also environmental attraction. Especially nano composite material which enhances the functional properties of components, extending the component life resulting to reduced the wastes and environmental contamination, has a great effect on various industrial area. The application of nano composite, depends on the polymer matrix and filler materials, has various application from semiconductor to medical field. In spite of nano composite merits, nano composite study are confined to a few special materials as a lab, scale because a few technical difficulties are still on hold. Therefore, the purpose of this study establishes the systematical planning to carried out the next generation projects on order to compete with other countries and overcome the protective policy of advanced countries with grasping over sea's development trends and our present status. (author).

  6. Study of High Performance Coronagraphic Techniques

    Science.gov (United States)

    Crane, Phil (Technical Monitor); Tolls, Volker

    2004-01-01

    The goal of the Study of High Performance Coronagraphic Techniques project (called CoronaTech) is: 1) to verify the Labeyrie multi-step speckle reduction method and 2) to develop new techniques to manufacture soft-edge occulter masks preferably with Gaussian absorption profile. In a coronagraph, the light from a bright host star which is centered on the optical axis in the image plane is blocked by an occulter centered on the optical axis while the light from a planet passes the occulter (the planet has a certain minimal distance from the optical axis). Unfortunately, stray light originating in the telescope and subsequent optical elements is not completely blocked causing a so-called speckle pattern in the image plane of the coronagraph limiting the sensitivity of the system. The sensitivity can be increased significantly by reducing the amount of speckle light. The Labeyrie multi-step speckle reduction method implements one (or more) phase correction steps to suppress the unwanted speckle light. In each step, the stray light is rephased and then blocked with an additional occulter which affects the planet light (or other companion) only slightly. Since the suppression is still not complete, a series of steps is required in order to achieve significant suppression. The second part of the project is the development of soft-edge occulters. Simulations have shown that soft-edge occulters show better performance in coronagraphs than hard-edge occulters. In order to utilize the performance gain of soft-edge occulters. fabrication methods have to be developed to manufacture these occulters according to the specification set forth by the sensitivity requirements of the coronagraph.

  7. High-Performance Monopropellants and Catalysts Evaluated

    Science.gov (United States)

    Reed, Brian D.

    2004-01-01

    The NASA Glenn Research Center is sponsoring efforts to develop advanced monopropellant technology. The focus has been on monopropellant formulations composed of an aqueous solution of hydroxylammonium nitrate (HAN) and a fuel component. HAN-based monopropellants do not have a toxic vapor and do not need the extraordinary procedures for storage, handling, and disposal required of hydrazine (N2H4). Generically, HAN-based monopropellants are denser and have lower freezing points than N2H4. The performance of HAN-based monopropellants depends on the selection of fuel, the HAN-to-fuel ratio, and the amount of water in the formulation. HAN-based monopropellants are not seen as a replacement for N2H4 per se, but rather as a propulsion option in their own right. For example, HAN-based monopropellants would prove beneficial to the orbit insertion of small, power-limited satellites because of this propellant's high performance (reduced system mass), high density (reduced system volume), and low freezing point (elimination of tank and line heaters). Under a Glenn-contracted effort, Aerojet Redmond Rocket Center conducted testing to provide the foundation for the development of monopropellant thrusters with an I(sub sp) goal of 250 sec. A modular, workhorse reactor (representative of a 1-lbf thruster) was used to evaluate HAN formulations with catalyst materials. Stoichiometric, oxygen-rich, and fuelrich formulations of HAN-methanol and HAN-tris(aminoethyl)amine trinitrate were tested to investigate the effects of stoichiometry on combustion behavior. Aerojet found that fuelrich formulations degrade the catalyst and reactor faster than oxygen-rich and stoichiometric formulations do. A HAN-methanol formulation with a theoretical Isp of 269 sec (designated HAN269MEO) was selected as the baseline. With a combustion efficiency of at least 93 percent demonstrated for HAN-based monopropellants, HAN269MEO will meet the I(sub sp) 250 sec goal.

  8. Optimizing High Performance Self Compacting Concrete

    Directory of Open Access Journals (Sweden)

    Raymond A Yonathan

    2017-01-01

    Full Text Available This paper’s objectives are to learn the effect of glass powder, silica fume, Polycarboxylate Ether, and gravel to optimizing composition of each factor in making High Performance SCC. Taguchi method is proposed in this paper as best solution to minimize specimen variable which is more than 80 variations. Taguchi data analysis method is applied to provide composition, optimizing, and the effect of contributing materials for nine variable of specimens. Concrete’s workability was analyzed using Slump flow test, V-funnel test, and L-box test. Compressive and porosity test were performed for the hardened state. With a dimension of 100×200 mm the cylindrical specimens were cast for compressive test with the age of 3, 7, 14, 21, 28 days. Porosity test was conducted at 28 days. It is revealed that silica fume contributes greatly to slump flow and porosity. Coarse aggregate shows the greatest contributing factor to L-box and compressive test. However, all factors show unclear result to V-funnel test.

  9. Ultra High Performance, Highly Reliable, Numeric Intensive Processors and Systems

    Science.gov (United States)

    1989-10-01

    to design high-performance DSP/IP systems using either off-the-shelf components or application specific integrated circuitry [ ASIC ]. -9 - HSDAL . ARO...are the chirp-z transform ( CZT ) [13] and (Rader’s) Prime Factor Transform (PFT) [11]. The RNS/ CZT is being studied by a group a MITRE [14] and is given...PFT RNS/CRNS/QRNS implementation has dynamic range requirements on the order of NQ2 (vs NQ4 for the CZT and much higher for the FFT). Therefore, the

  10. High performance internal reforming unit for high temperature fuel cells

    Science.gov (United States)

    Ma, Zhiwen; Venkataraman, Ramakrishnan; Novacco, Lawrence J.

    2008-10-07

    A fuel reformer having an enclosure with first and second opposing surfaces, a sidewall connecting the first and second opposing surfaces and an inlet port and an outlet port in the sidewall. A plate assembly supporting a catalyst and baffles are also disposed in the enclosure. A main baffle extends into the enclosure from a point of the sidewall between the inlet and outlet ports. The main baffle cooperates with the enclosure and the plate assembly to establish a path for the flow of fuel gas through the reformer from the inlet port to the outlet port. At least a first directing baffle extends in the enclosure from one of the sidewall and the main baffle and cooperates with the plate assembly and the enclosure to alter the gas flow path. Desired graded catalyst loading pattern has been defined for optimized thermal management for the internal reforming high temperature fuel cells so as to achieve high cell performance.

  11. Multiwavelength and Polarimetric Analysis of the Flat Spectrum Radio Quasars 3C 273 and 3C 279

    Science.gov (United States)

    Fernandes, Sunil; Patiño-Álvarez, Victor; Chavushyan, Vahram; Schlegel, Eric M.; Lopez-Rodriguez, Enrique; León-Tavares, Jonathan; Carrasco, Luis; Valdés, José; Carramiñana, Alberto

    2017-01-01

    This poster presents results of multiwavelength analyses of 3C 273 and 3C 279. The main goals were to identify the gamma-ray emission region and dominant high-energy emission processes. Our methodology consisted of analyzing light curves from radio to gamma-rays over 6 - 8 years and polarimetric, spectral and line emission behavior.In 3C 279, we found that the emission from millimeter to ultraviolet was simultaneous and therefore co-spatial. We identified two active states where different high-energy emission processes were dominant. We found multiwavelength flaring events consistent with component ejections and shocks. We proposed that the gamma-ray emission region changed over time based on observations of both simultaneous and delayed gamma-rays emission with respect to low-energy emission during different time-frames.In 3C 273, we identified a non-thermal flare related to a component ejection and a thermal flare related to accretion. From reverberation mapping we found that the broad line region dynamical behavior over time possibly affects the derived supermassive black hole mass.In both objects we found that the gamma-ray spectral index was variable, and a trend of harder spectral index with higher gamma-ray luminosity. From the identification of different dominant high-energy emission processes, we concluded that the dominant high-energy emission mechanism changes with time. Overall, we concluded that similar results from both objects points to behavior that is potentially common to flat spectrum radio quasars. Increasing the sample size of objects analyzed with similar methodologies will provide more results to confirm or refine our conclusions.

  12. High-performance computers for unmanned vehicles

    Science.gov (United States)

    Toms, David; Ettinger, Gil J.

    2005-10-01

    The present trend of increasing functionality onboard unmanned vehicles is made possible by rapid advances in high-performance computers (HPCs). An HPC is characterized by very high computational capability (100s of billions of operations per second) contained in lightweight, rugged, low-power packages. HPCs are critical to the processing of sensor data onboard these vehicles. Operations such as radar image formation, target tracking, target recognition, signal intelligence signature collection and analysis, electro-optic image compression, and onboard data exploitation are provided by these machines. The net effect of an HPC is to minimize communication bandwidth requirements and maximize mission flexibility. This paper focuses on new and emerging technologies in the HPC market. Emerging capabilities include new lightweight, low-power computing systems: multi-mission computing (using a common computer to support several sensors); onboard data exploitation; and large image data storage capacities. These new capabilities will enable an entirely new generation of deployed capabilities at reduced cost. New software tools and architectures available to unmanned vehicle developers will enable them to rapidly develop optimum solutions with maximum productivity and return on investment. These new technologies effectively open the trade space for unmanned vehicle designers.

  13. New high performance Si for optical devices

    Science.gov (United States)

    Tenma, T.; Matsuzaka, M.; Sako, R.; Takase, K.; Chiba, K.

    2016-05-01

    Against the backdrop of a growing demand in the areas of smart buildings, security, vehicle installation, and other applications, the market for far infrared cameras is expected to grow significantly in the future. However, since germanium (Ge) and chalcogenide glass, which have been used as the lens materials of far infrared cameras, are very expensive or highly toxic, there are some problems supporting the growing demand. We have therefore focused attention on silicon, which is inexpensive and less toxic. Although silicon has been used as a lens material of far infrared cameras, there are some problems remaining to be solved: Cz silicon is inexpensive but delivers low transmittance, and Fz silicon delivers sufficient transmittance but is expensive. We have developed New Cz silicon, which delivers high transmittance as Fz silicon does, and is inexpensive as conventional Cz silicon is. We have already started its sample work at both companies in Japan and overseas and have obtained excellent performance results. Mass production is scheduled to start in this fiscal year.

  14. High performance BGMI circuit for VLWIR FPAs

    Science.gov (United States)

    Hao, Li-chao; Chen, Hong-lei; Huang, Ai-bo; Zhang, Jun-ling; Ding, Rui-jun

    2013-09-01

    An improved CMOS readout integrated circuit (ROIC) for N-on-P very long wavelength (VLWIR) detectors is designed, which has the ability to operate with a simple background suppression. It increases the integration time and the signal-to-noise ratio (SNR) of image data. A buffered gate modulation input (BGMI) cell as input circuit provides a low input resistance, high injection efficiency, and precise biasing voltage to the photodiode. By theoretically analyzing the characteristic parameters of MOS device at low temperature, a high gain's feedback amplifier is devised which using a differential stage to provide the inverting gain to improve linearity and to provide tight control of the detector bias. The final chip is fabricated with HHNEC 0.35um 1P4M process technology. The measurement results of the fabricated readout chip under 50K have successfully verified both readout function and performance improvement. With the 5.0V power supply, ROIC provides the output dynamic range over 2.5V. At the same time, the total power dissipation is less than 200mW, and the maximum readout speed is more than 2.5MHz.

  15. THE STRUCTURE AND EMISSION MODEL OF THE RELATIVISTIC JET IN THE QUASAR 3C 279 INFERRED FROM RADIO TO HIGH-ENERGY {gamma}-RAY OBSERVATIONS IN 2008-2010

    Energy Technology Data Exchange (ETDEWEB)

    Hayashida, M.; Madejski, G. M.; Chiang, J.; Blandford, R. D.; Buehler, R. [Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford University, 2575 Sand Hill Road M/S 29, Menlo Park, CA 94025 (United States); Nalewajko, K. [University of Colorado, UCB 440, Boulder, CO 80309 (United States); Sikora, M. [Nicolaus Copernicus Astronomical Center, 00-716 Warsaw (Poland); Wehrle, A. E. [Space Science Institute, Boulder, CO 80301 (United States); Ogle, P. [Infrared Processing and Analysis Center, California Institute of Technology Pasadena, CA 91125 (United States); Collmar, W. [Max-Planck Institut fuer Extraterrestrische Physik, 85748 Garching (Germany); Larsson, S. [Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden); Fukazawa, Y.; Itoh, R. [Department of Physical Sciences, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Stawarz, L. [Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Richards, J. L.; Max-Moerbeck, W.; Readhead, A. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Cavazzuti, E.; Ciprini, S. [Agenzia Spaziale Italiana (ASI) Science Data Center, I-00044 Frascati (Roma) (Italy); Gehrels, N., E-mail: mahaya@slac.stanford.edu, E-mail: madejski@slac.stanford.edu, E-mail: knalew@Colorado.edu, E-mail: sikora@camk.edu.pl [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); and others

    2012-08-01

    We present time-resolved broadband observations of the quasar 3C 279 obtained from multi-wavelength campaigns conducted during the first two years of the Fermi Gamma-ray Space Telescope mission. While investigating the previously reported {gamma}-ray/optical flare accompanied by a change in optical polarization, we found that the optical emission appears to be delayed with respect to the {gamma}-ray emission by about 10 days. X-ray observations reveal a pair of 'isolated' flares separated by {approx}90 days, with only weak {gamma}-ray/optical counterparts. The spectral structure measured by Spitzer reveals a synchrotron component peaking in the mid-infrared band with a sharp break at the far-infrared band during the {gamma}-ray flare, while the peak appears in the millimeter (mm)/submillimeter (sub-mm) band in the low state. Selected spectral energy distributions are fitted with leptonic models including Comptonization of external radiation produced in a dusty torus or the broad-line region. Adopting the interpretation of the polarization swing involving propagation of the emitting region along a curved trajectory, we can explain the evolution of the broadband spectra during the {gamma}-ray flaring event by a shift of its location from {approx}1 pc to {approx}4 pc from the central black hole. On the other hand, if the {gamma}-ray flare is generated instead at sub-pc distance from the central black hole, the far-infrared break can be explained by synchrotron self-absorption. We also model the low spectral state, dominated by the mm/sub-mm peaking synchrotron component, and suggest that the corresponding inverse-Compton component explains the steady X-ray emission.

  16. Hydrodynamical Simulations of Colliding Jets: Modeling 3C 75

    Science.gov (United States)

    Molnar, S. M.; Schive, H.-Y.; Birkinshaw, M.; Chiueh, T.; Musoke, G.; Young, A. J.

    2017-01-01

    Radio observations suggest that 3C 75, located in the dumbbell shaped galaxy NGC 1128 at the center of Abell 400, hosts two colliding jets. Motivated by this source, we perform three-dimensional hydrodynamical simulations using a modified version of the GPU-accelerated Adaptive-MEsh-Refinement hydrodynamical parallel code (GAMER) to study colliding extragalactic jets. We find that colliding jets can be cast into two categories: (1) bouncing jets, in which case the jets bounce off each other keeping their identities, and (2) merging jets, when only one jet emerges from the collision. Under some conditions the interaction causes the jets to break up into oscillating filaments of opposite helicity, with consequences for their downstream stability. When one jet is significantly faster than the other and the impact parameter is small, the jets merge; the faster jet takes over the slower one. In the case of merging jets, the oscillations of the filaments, in projection, may show a feature that resembles a double helix, similar to the radio image of 3C 75. Thus we interpret the morphology of 3C 75 as a consequence of the collision of two jets with distinctly different speeds at a small impact parameter, with the faster jet breaking up into two oscillating filaments.

  17. High-performance commercial building systems

    Energy Technology Data Exchange (ETDEWEB)

    Selkowitz, Stephen

    2003-10-01

    This report summarizes key technical accomplishments resulting from the three year PIER-funded R&D program, ''High Performance Commercial Building Systems'' (HPCBS). The program targets the commercial building sector in California, an end-use sector that accounts for about one-third of all California electricity consumption and an even larger fraction of peak demand, at a cost of over $10B/year. Commercial buildings also have a major impact on occupant health, comfort and productivity. Building design and operations practices that influence energy use are deeply engrained in a fragmented, risk-averse industry that is slow to change. Although California's aggressive standards efforts have resulted in new buildings designed to use less energy than those constructed 20 years ago, the actual savings realized are still well below technical and economic potentials. The broad goal of this program is to develop and deploy a set of energy-saving technologies, strategies, and techniques, and improve processes for designing, commissioning, and operating commercial buildings, while improving health, comfort, and performance of occupants, all in a manner consistent with sound economic investment practices. Results are to be broadly applicable to the commercial sector for different building sizes and types, e.g. offices and schools, for different classes of ownership, both public and private, and for owner-occupied as well as speculative buildings. The program aims to facilitate significant electricity use savings in the California commercial sector by 2015, while assuring that these savings are affordable and promote high quality indoor environments. The five linked technical program elements contain 14 projects with 41 distinct R&D tasks. Collectively they form a comprehensive Research, Development, and Demonstration (RD&D) program with the potential to capture large savings in the commercial building sector, providing significant economic benefits to

  18. Photometric reverberation mapping of 3C120

    CERN Document Server

    Nuñez, F Pozo; Westhues, C; Bruckmann, C; Haas, M; Chini, R; Steenbrugge, K; Murphy, M; 10.1051/0004-6361/201219107

    2013-01-01

    We present the results of a five month monitoring campaign of the local active galactic nuclei (AGN) 3C120. Observations with a median sampling of two days were conducted with the robotic 15cm telescope VYSOS-6 located near Cerro Armazones in Chile. Broad band (B,V) and narrow band (NB) filters were used in order to measure fluxes of the AGN and the H_beta broad line region (BLR) emission line. The NB flux is constituted by about 50% continuum and 50% H_beta emission line. To disentangle line and continuum flux, a synthetic H_beta light curve was created by subtracting a scaled V-band light curve from the NB light curve. Here we show that the H_beta emission line responds to continuum variations with a rest frame lag of 23.6 +/- 1.69 days. We estimate a virial mass of the central black hole M_BH = 57 +/- 27 * 10^6 solar masses, by combining the obtained lag with the velocity dispersion of a single contemporaneous spectrum. Using the flux variation gradient (FVG) method, we determined the host galaxy subtracte...

  19. Compact high performance spectrometers using computational imaging

    Science.gov (United States)

    Morton, Kenneth; Weisberg, Arel

    2016-05-01

    Compressive sensing technology can theoretically be used to develop low cost compact spectrometers with the performance of larger and more expensive systems. Indeed, compressive sensing for spectroscopic systems has been previously demonstrated using coded aperture techniques, wherein a mask is placed between the grating and a charge coupled device (CCD) and multiple measurements are collected with different masks. Although proven effective for some spectroscopic sensing paradigms (e.g. Raman), this approach requires that the signal being measured is static between shots (low noise and minimal signal fluctuation). Many spectroscopic techniques applicable to remote sensing are inherently noisy and thus coded aperture compressed sensing will likely not be effective. This work explores an alternative approach to compressed sensing that allows for reconstruction of a high resolution spectrum in sensing paradigms featuring significant signal fluctuations between measurements. This is accomplished through relatively minor changes to the spectrometer hardware together with custom super-resolution algorithms. Current results indicate that a potential overall reduction in CCD size of up to a factor of 4 can be attained without a loss of resolution. This reduction can result in significant improvements in cost, size, and weight of spectrometers incorporating the technology.

  20. Initial rheological description of high performance concretes

    Directory of Open Access Journals (Sweden)

    Alessandra Lorenzetti de Castro

    2006-12-01

    Full Text Available Concrete is defined as a composite material and, in rheological terms, it can be understood as a concentrated suspension of solid particles (aggregates in a viscous liquid (cement paste. On a macroscopic scale, concrete flows as a liquid. It is known that the rheological behavior of the concrete is close to that of a Bingham fluid and two rheological parameters regarding its description are needed: yield stress and plastic viscosity. The aim of this paper is to present the initial rheological description of high performance concretes using the modified slump test. According to the results, an increase of yield stress was observed over time, while a slight variation in plastic viscosity was noticed. The incorporation of silica fume showed changes in the rheological properties of fresh concrete. The behavior of these materials also varied with the mixing procedure employed in their production. The addition of superplasticizer meant that there was a large reduction in the mixture's yield stress, while plastic viscosity remained practically constant.

  1. Durability of High Performance Color Hardener

    Institute of Scientific and Technical Information of China (English)

    MA Bao-guo; DONG Rong-zhen; ZHU Hong-bo; ZHANG Li; JIAN Shou-wei

    2004-01-01

    The properties of high performance color hardener (HPCH) and the mechanism were studied.HPCH is a composite system, which is composed of cementitious and auxiliary cementing materials, composite additives, abrasion resistance component (aggregate) and pigment. The porosity and pore structure of the material are obviously improved due to the activation, filling and adsorption of auxiliary cementing materials, thus resulting in a great increase of binding capacity for ions in HPCH and the obstacles of ion migrating.The density of material structure, bonding capacity of cementitious material to the abrasion-resisting component and the corrosion resistance are greatly and effectively improved by adding the auxiliary cementing materials and compound additives. According to the tests of dry shrinkage, sulphate resistance, chloride permeability and Ca(OH)2 content distribution, the property superiority of HPCH is analyzed.The mechanism of materials modification of HPCH is explained from the microscopic point of view by testing the pore structure and pore distribution via the mercury intrusion pressure method.

  2. Alternative High-Performance Ceramic Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Sundaram, S. K. [Alfred Univ., NY (United States)

    2017-02-01

    This final report (M5NU-12-NY-AU # 0202-0410) summarizes the results of the project titled “Alternative High-Performance Ceramic Waste Forms,” funded in FY12 by the Nuclear Energy University Program (NEUP Project # 12-3809) being led by Alfred University in collaboration with Savannah River National Laboratory (SRNL). The overall focus of the project is to advance fundamental understanding of crystalline ceramic waste forms and to demonstrate their viability as alternative waste forms to borosilicate glasses. We processed single- and multiphase hollandite waste forms based on simulated waste streams compositions provided by SRNL based on the advanced fuel cycle initiative (AFCI) aqueous separation process developed in the Fuel Cycle Research and Development (FCR&D). For multiphase simulated waste forms, oxide and carbonate precursors were mixed together via ball milling with deionized water using zirconia media in a polyethylene jar for 2 h. The slurry was dried overnight and then separated from the media. The blended powders were then subjected to melting or spark plasma sintering (SPS) processes. Microstructural evolution and phase assemblages of these samples were studied using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion analysis of x-rays (EDAX), wavelength dispersive spectrometry (WDS), transmission electron spectroscopy (TEM), selective area x-ray diffraction (SAXD), and electron backscatter diffraction (EBSD). These results showed that the processing methods have significant effect on the microstructure and thus the performance of these waste forms. The Ce substitution into zirconolite and pyrochlore materials was investigated using a combination of experimental (in situ XRD and x-ray absorption near edge structure (XANES)) and modeling techniques to study these single phases independently. In zirconolite materials, a transition from the 2M to the 4M polymorph was observed with increasing Ce content. The resulting

  3. 添加WS2/(Ni-P)包覆的激光制备高温自润滑耐磨复合涂层%High temperature self-lubricating wear-resistant NiCr-Cr3 C2/30 % WS2 (Ni-P)composite coating fabricated by laser cladding

    Institute of Scientific and Technical Information of China (English)

    郑晨; 刘秀波; 杨茂盛; 王明娣; 石世宏; 傅戈雁; 齐龙浩

    2013-01-01

    为抑制WS2在激光熔覆过程中的分解,增加其与金属基体的相容性,采用化学镀的方法,在WS2粉末颗粒表面包覆一层微米级Ni-P合金,对比研究了添加包覆粉末和未包覆粉末所制备的高温自润滑耐磨复合涂层的微观组织和室温、300℃和600℃下的摩擦学性能.NiCr-Cr3C2/30% WS2(Ni-P)涂层组织主要为初生树枝状Cr7C3、共晶γ-(Fe,Ni)/Cr7C3和CrS,以及少量弥散分布的WS2;对涂层进行摩擦学实验表明,添加包覆粉末所制备的涂层摩擦学性能更佳,室温和300℃时,NiCr-Cr3C2/30%WS2(Ni-P)涂层有较低的摩擦系数,且室温、300℃和600℃时,NiCr-Cr3C2/30% WS2(Ni-P)涂层磨损率都低于NiCr-Cr3C2/30%WS2涂层.%In order to decrease WS2 decomposition and increase its compatibility with the metal matrix during the process of laser cladding,the WS2 powder was encapsulated with a micron-Ni-P layer by electroless plating.The microstructure and tribological properties of the NiCr-Cr3C2/30% WS2 and NiCr-Cr3C2/30% WS2 (Ni-P) high temperature self-lubricating wear-resistant composite coatings at RT(room temperature),300 ℃ and 600 ℃ were investigated,respectively.The results show that the NiCr-Cr3 C2/30% WS2 (Ni-P) coating consists of primary Cr7 C3 dendrite,γ-(Fe,Ni)/Cr7 C3 eutectic and CrS,Ni-P electroless plating decreases the decomposition of WS2 to some extent,the WS2 solid lubrication particles are uniformly dispersed in the ductile γ,-(Fe,Ni) /Cr7 C3 matrix.Friction and wear experiments indicate that the tribological properties of the NiCr-Cr3 C2/30% WS2 (Ni-P) coating is better than that of the NiCr-Cr3 C2/30% WS2 coating,the NiCr-Cr3C2/30% WS2 (Ni-P) coating presents lower friction coefficient at RT and 300 ℃ and lower wear rate from RT to the elevated temperature of 600 ℃.

  4. Novel synergistic 0.9LiMn0.9Fe0.1PO4·0.1Na3V2(PO4)2F3/C nano-hybrid cathode with enhanced electrochemical performance for lithium-ion batteries

    Science.gov (United States)

    Zhang, Zhijian; Hu, Guorong; Cao, Yanbing; Duan, Jianguo; Du, Ke; Peng, Zhongdong

    2016-01-01

    The nanostructured 0.9LiMn0.9Fe0.1PO4·0.1Na3V2(PO4)2F3/C composites are successfully synthesized by a facile solvothermal method followed by mechanical activation and subsequent carbonthermal reduction process. Behaviours of bi-phase co-existence and element mutual-substitution have been investigated by XRD, TEM/EDX and FTIR. The result shows that the composites have dual phase boundaries including the semi-coherent phase interface and incoherent phase interface, as well as the advantage of Na3V2(PO4)2F3 acting as ionic conductor. Due to the multifunctional phase and (Mn,Fe)-V mutual doping as well as nano-carbon continual conducting network, enhanced Li+ migration and charge transfer of nano-hybrid is obtained. Compared with pristine one, the 0.9LiMn0.9Fe0.1PO4·0.1Na3V2(PO4)2F3/C composites exhibit high rate capability and cycling ability, showing 125.5, 106.4 mAh g-1 at 1.0 C, 3.0 C at room temperature, respectively, with high capacity retention up to 93.9% after 600th at 2 C.

  5. High-performance commercial building systems

    Energy Technology Data Exchange (ETDEWEB)

    Selkowitz, Stephen

    2003-10-01

    This report summarizes key technical accomplishments resulting from the three year PIER-funded R&D program, ''High Performance Commercial Building Systems'' (HPCBS). The program targets the commercial building sector in California, an end-use sector that accounts for about one-third of all California electricity consumption and an even larger fraction of peak demand, at a cost of over $10B/year. Commercial buildings also have a major impact on occupant health, comfort and productivity. Building design and operations practices that influence energy use are deeply engrained in a fragmented, risk-averse industry that is slow to change. Although California's aggressive standards efforts have resulted in new buildings designed to use less energy than those constructed 20 years ago, the actual savings realized are still well below technical and economic potentials. The broad goal of this program is to develop and deploy a set of energy-saving technologies, strategies, and techniques, and improve processes for designing, commissioning, and operating commercial buildings, while improving health, comfort, and performance of occupants, all in a manner consistent with sound economic investment practices. Results are to be broadly applicable to the commercial sector for different building sizes and types, e.g. offices and schools, for different classes of ownership, both public and private, and for owner-occupied as well as speculative buildings. The program aims to facilitate significant electricity use savings in the California commercial sector by 2015, while assuring that these savings are affordable and promote high quality indoor environments. The five linked technical program elements contain 14 projects with 41 distinct R&D tasks. Collectively they form a comprehensive Research, Development, and Demonstration (RD&D) program with the potential to capture large savings in the commercial building sector, providing significant economic benefits to

  6. High Performance Input/Output Systems for High Performance Computing and Four-Dimensional Data Assimilation

    Science.gov (United States)

    Fox, Geoffrey C.; Ou, Chao-Wei

    1997-01-01

    The approach of this task was to apply leading parallel computing research to a number of existing techniques for assimilation, and extract parameters indicating where and how input/output limits computational performance. The following was used for detailed knowledge of the application problems: 1. Developing a parallel input/output system specifically for this application 2. Extracting the important input/output characteristics of data assimilation problems; and 3. Building these characteristics s parameters into our runtime library (Fortran D/High Performance Fortran) for parallel input/output support.

  7. High Performance Liquid Chromatography/Video Fluorometry. Part I. Instrumentation.

    Science.gov (United States)

    1981-09-30

    High Performance Liquid Chromatography /Video...PERIOD COVERED High Performance Liquid Chromatography /Video .. / Fluorometry. Part I. Instrumentation. . Interim/ echnicaliepart,. 6. PERFORMING ORG...34Entered SECURITY CLASSIFICATION OF THIS OlAGE (When Data Entered) II1| III I I I I E I II ... .. High Performance Liquid Chromatography

  8. High performance MEMS micro-gyroscope

    Science.gov (United States)

    Bae, S. Y.; Hayworth, K. J.; Yee, K. Y.; Shcheglov, K.; Challoner, A. D.; Wiberg, D. V.

    2002-01-01

    This paper reports on JPL's on-going research into MEMS gyroscopes. This paper will describe the gyroscope's fabrication-methods, a new 8-electrode layout developed to improve performance, and performance statistics of a batch of six gyroscopes recently rate tested.

  9. pH值和螯合剂复合作用对正极材料Li3V2(PO4)3/C性能的影响%Influence of pH value and chelating reagent on performance of Li3V2(PO4)3/C cathode material

    Institute of Scientific and Technical Information of China (English)

    向伟; 唐艳; 王雁英; 钟本和; 方为茂; 刘恒; 郭孝东

    2013-01-01

    The Li3V2(PO4)3/C composite cathode material was synthesized via sol-gel method using three different chelating agents (citric acid,salicylic acid and polyacrylic acid) at pH value of 3 or 7.The crystal structure,morphology,specific surface area and electrochemical performance of the prepared samples were investigated by X-ray diffraction (XRD),scanning electron microscopy (SEM),cyclic voltammetry (CV),electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge test.The results show that the effects of pH value on the performance of the prepared materials are greatly related to the chelating agents.With salicylic acid or polyacrylic acid as the chelating reagent,the structure,morphology and electrochemical performance of the samples are greatly influenced by the pH values.However,the structure of the materials with citric acid as the chelating agent does not change as pH value changes,and the materials own uniform particle size distribution and good electrochemical performance.It delivers an initial discharge capacity of 113.58 mA·h/g at 10C,remaining as high as 108.48 mA·h/g after 900 cycles,with a capacity retention of 95.51%.%使用不同的螯合剂(柠檬酸、水杨酸和聚丙烯酸)在不同的pH值条件下,采用溶胶-凝胶法合成Li3V2(PO4)3/C正极材料.通过X射线衍射(XRD)、扫描电镜(SEM)、循环伏安(CV)、电化学阻抗谱(EIS)以及恒流充放电测试等方法,研究材料的结构、形貌及电化学性能.结果表明,pH值对材料性能的影响与所采用的螯合剂有很大的关系.当采用水杨酸和聚丙烯酸为螯合剂时,升高pH值对材料的结构、形貌和电化学性能有较大的负面影响.而采用柠檬酸为螯合剂时,材料结构无变化且颗粒分布更均匀,高倍率放电性能和循环性能也得到改善,10C首次放电容量为113.58 mA·h/g,循环900次后容量保持率为95.51%.

  10. Durability and Performance of High Performance Infiltration Cathodes

    DEFF Research Database (Denmark)

    Samson, Alfred Junio; Søgaard, Martin; Hjalmarsson, Per

    2013-01-01

    The performance and durability of solid oxide fuel cell (SOFC) cathodes consisting of a porous Ce0.9Gd0.1O1.95 (CGO) infiltrated with nitrates corresponding to the nominal compositions La0.6Sr0.4Co1.05O3-δ (LSC), LaCoO3-δ (LC), and Co3O4 are discussed. At 600°C, the polarization resistance, Rp......, varied as: LSC (0.062Ωcm2)cathode was found to depend on the infiltrate firing temperature and is suggested to originate...... of the infiltrate but also from a better surface exchange property. A 450h test of an LSC-infiltrated CGO cathode showed an Rp with final degradation rate of only 11mΩcm2kh-1. An SOFC with an LSC-infiltrated CGO cathode tested for 1,500h at 700°C and 0.5Acm-2 (60% fuel, 20% air utilization) revealed no measurable...

  11. High Performance Computing in Science and Engineering '02 : Transactions of the High Performance Computing Center

    CERN Document Server

    Jäger, Willi

    2003-01-01

    This book presents the state-of-the-art in modeling and simulation on supercomputers. Leading German research groups present their results achieved on high-end systems of the High Performance Computing Center Stuttgart (HLRS) for the year 2002. Reports cover all fields of supercomputing simulation ranging from computational fluid dynamics to computer science. Special emphasis is given to industrially relevant applications. Moreover, by presenting results for both vector sytems and micro-processor based systems the book allows to compare performance levels and usability of a variety of supercomputer architectures. It therefore becomes an indispensable guidebook to assess the impact of the Japanese Earth Simulator project on supercomputing in the years to come.

  12. Final Report on DTRA Basic Research Project #BRCALL08-Per3-C-2-0006 "High-Z Non-Equilibrium Physics and Bright X-ray Sources with New Laser Targets"

    Energy Technology Data Exchange (ETDEWEB)

    Colvin, Jeffrey D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-06-01

    This project had two major goals. Final Goal: obtain spectrally resolved, absolutely calibrated x-ray emission data from uniquely uniform mm-scale near-critical-density high-Z plasmas not in local thermodynamic equilibrium (LTE) to benchmark modern detailed atomic physics models. Scientific significance: advance understanding of non-LTE atomic physics. Intermediate Goal: develop new nano-fabrication techniques to make suitable laser targets that form the required highly uniform non-LTE plasmas when illuminated by high-intensity laser light. Scientific significance: advance understanding of nano-science. The new knowledge will allow us to make x-ray sources that are bright at the photon energies of most interest for testing radiation hardening technologies, the spectral energy range where current x-ray sources are weak. All project goals were met.

  13. Toward high performance in Powder Metallurgy

    Directory of Open Access Journals (Sweden)

    Torralba, José M.

    2014-06-01

    Full Text Available Powder Metallurgy (PM is technology well known for mass production of parts at low cost but usually with worse mechanical properties than same parts obtained by alternative routes. But using this technology, high performance materials can be obtained, depending of the processing route and the type and amount of porosity. In this paper, a brief review of the capabilities of powder technology is made with the objective of attaining the highest level of mechanical and physical properties. For this purpose, different strategies over the processing can be chosen: to act over the density/porosity level and properties of the pores, to act over strengthening mechanisms apart from the density of the material (the alloying system, the microstructure, the grain size,.., to improve the sintering activity by different routes and to use techniques that avoid the grain growth during sintering.La Pulvimetalurgia es una tecnología bien conocida por su faceta de producir piezas de forma masiva a bajo coste, pero habitualmente con una pérdida de propiedades mecánicas si se la compara con tecnologías alternativas para obtener las mismas piezas. Sin embargo, mediante esta tecnología, también se pueden obtener piezas de altas prestaciones, dependiendo de la ruta de procesado y del nivel de porosidad. En este trabajo, se realiza una sucinta revisión de las posibilidades de la tecnología de polvos que permitirían obtener los mayores niveles de prestaciones en cuanto a propiedades mecánicas y físicas. Se pueden elegir distintas estrategias en el procesado: actuar sobre el nivel de densidad/porosidad y las propiedades de los poros, actuar sobre mecanismos de endurecimiento distintos a la densidad (el sistema de aleación, la microestructura, el tamaño de grano,…, mejorar la activación durante la sinterización y utilizar técnicas que inhiban el tamaño de grano durante la sinterización.

  14. From adaptive to high-performance structures

    NARCIS (Netherlands)

    Teuffel, P.

    2011-01-01

    Multiple design aspects influence the building performance such as architectural criteria, various environmental impacts and user behaviour. Specific examples are sun, wind, temperatures, function, occupancy, socio-cultural aspects and other contextual aspects and needs. Even though these aspects ar

  15. High Performance Electrolyzers for Hybrid Thermochemical Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Dr. John W. Weidner

    2009-05-10

    Extensive electrolyzer testing was performed at the University of South Carolina (USC). Emphasis was given to understanding water transport under various operating (i.e., temperature, membrane pressure differential and current density) and design (i.e., membrane thickness) conditions when it became apparent that water transport plays a deciding role in cell voltage. A mathematical model was developed to further understand the mechanisms of water and SO2 transport, and to predict the effect of operating and design parameters on electrolyzer performance.

  16. Facile Synthesis of Layer Structured GeP3/C with Stable Chemical Bonding for Enhanced Lithium-Ion Storage

    Science.gov (United States)

    Qi, Wen; Zhao, Haihua; Wu, Ying; Zeng, Hong; Tao, Tao; Chen, Chao; Kuang, Chunjiang; Zhou, Shaoxiong; Huang, Yunhui

    2017-01-01

    Recently, metal phosphides have been investigated as potential anode materials because of higher specific capacity compared with those of carbonaceous materials. However, the rapid capacity fade upon cycling leads to poor durability and short cycle life, which cannot meet the need of lithium-ion batteries with high energy density. Herein, we report a layer-structured GeP3/C nanocomposite anode material with high performance prepared by a facial and large-scale ball milling method via in-situ mechanical reaction. The P-O-C bonds are formed in the composite, leading to close contact between GeP3 and carbon. As a result, the GeP3/C anode displays excellent lithium storage performance with a high reversible capacity up to 1109 mA h g−1 after 130 cycles at a current density of 0.1 A g−1. Even at high current densities of 2 and 5 A g−1, the reversible capacities are still as high as 590 and 425 mA h g−1, respectively. This suggests that the GeP3/C composite is promising to achieve high-energy lithium-ion batteries and the mechanical milling is an efficient method to fabricate such composite electrode materials especially for large-scale application. PMID:28240247

  17. Benchmarking: More Aspects of High Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Ravindrudu, Rahul [Iowa State Univ., Ames, IA (United States)

    2004-01-01

    The original HPL algorithm makes the assumption that all data can be fit entirely in the main memory. This assumption will obviously give a good performance due to the absence of disk I/O. However, not all applications can fit their entire data in memory. These applications which require a fair amount of I/O to move data to and from main memory and secondary storage, are more indicative of usage of an Massively Parallel Processor (MPP) System. Given this scenario a well designed I/O architecture will play a significant part in the performance of the MPP System on regular jobs. And, this is not represented in the current Benchmark. The modified HPL algorithm is hoped to be a step in filling this void. The most important factor in the performance of out-of-core algorithms is the actual I/O operations performed and their efficiency in transferring data to/from main memory and disk, Various methods were introduced in the report for performing I/O operations. The I/O method to use depends on the design of the out-of-core algorithm. Conversely, the performance of the out-of-core algorithm is affected by the choice of I/O operations. This implies, good performance is achieved when I/O efficiency is closely tied with the out-of-core algorithms. The out-of-core algorithms must be designed from the start. It is easily observed in the timings for various plots, that I/O plays a significant part in the overall execution time. This leads to an important conclusion, retro-fitting an existing code may not be the best choice. The right-looking algorithm selected for the LU factorization is a recursive algorithm and performs well when the entire dataset is in memory. At each stage of the loop the entire trailing submatrix is read into memory panel by panel. This gives a polynomial number of I/O reads and writes. If the left-looking algorithm was selected for the main loop, the number of I/O operations involved will be linear on the number of columns. This is due to the data access

  18. High Performance Home Building Guide for Habitat for Humanity Affiliates

    Energy Technology Data Exchange (ETDEWEB)

    Lindsey Marburger

    2010-10-01

    This guide covers basic principles of high performance Habitat construction, steps to achieving high performance Habitat construction, resources to help improve building practices, materials, etc., and affiliate profiles and recommendations.

  19. Yap: A High-Performance Cursor on Target Message Router

    Science.gov (United States)

    2014-09-01

    Yap: A High-Performance Cursor on Target Message Router by Jesse Kovach ARL-TR-7096 September 2014...High-Performance Cursor on Target Message Router Jesse Kovach Computational and Information Sciences Directorate, ARL...

  20. High performance SMC matrix for structural applications

    Science.gov (United States)

    Salard, T.; Lortie, F.; Gérard, J. F.; Peyre, C.

    2016-07-01

    Mechanical properties of a common SMC (Sheet Molding Compound) matrix constituted of a vinylester resin and a Low-Profile Additive (LPA) were compared to those of vinylester modified with core-shell rubber (CSR) particles. Valuable properties are brought by CSR, especially high impact strength, high fracture toughness with little loss in stiffness, in spite of the presence of CSR agglomerates in blends.

  1. Robust High Performance Aquaporin based Biomimetic Membranes

    DEFF Research Database (Denmark)

    Helix Nielsen, Claus; Zhao, Yichun; Qiu, C.;

    2013-01-01

    on top of a support membrane. Control membranes, either without aquaporins or with the inactive AqpZ R189A mutant aquaporin served as controls. The separation performance of the membranes was evaluated by cross-flow forward osmosis (FO) and reverse osmosis (RO) tests. In RO the ABM achieved a water...

  2. Mastering JavaScript high performance

    CERN Document Server

    Adams, Chad R

    2015-01-01

    If you are a JavaScript developer with some experience in development and want to increase the performance of JavaScript projects by building faster web apps, then this book is for you. You should know the basic concepts of JavaScript.

  3. High performance management bij franchise-supermarkten

    NARCIS (Netherlands)

    Sloot, Laurens; van Nierop, Erjen; de Waal, Andre

    2016-01-01

    In dit artikel wordt een onderzoek gepresenteerd naar de mate waarin franchise-supermarkten voldoen aan de vijf factoren van high performanceorganisaties (HPO): hoge kwaliteit managers, hoge kwaliteit medewerkers, openheid en actiegerichtheid, continue verbetering en vernieuwing, en langetermijngeri

  4. High Power Performance of Rod Fiber Amplifiers

    DEFF Research Database (Denmark)

    Johansen, Mette Marie; Michieletto, Mattia; Kristensen, Torben;

    2015-01-01

    An improved version of the DMF rod fiber is tested in a high power setup delivering 360W of stable signal power. Multiple testing degrades the fiber and transverse modal instability threshold from >360W to ~290W.......An improved version of the DMF rod fiber is tested in a high power setup delivering 360W of stable signal power. Multiple testing degrades the fiber and transverse modal instability threshold from >360W to ~290W....

  5. Thermal Hysteresis of MEMS Packaged Capacitive Pressure Sensor (CPS) Based 3C-SiC

    Science.gov (United States)

    Marsi, N.; Majlis, B. Y.; Mohd-Yasin, F.; Hamzah, A. A.; Mohd Rus, A. Z.

    2016-11-01

    Presented herein are the effects of thermal hysteresis analyses of the MEMS packaged capacitive pressure sensor (CPS). The MEMS CPS was employed on Si-on-3C-SiC wafer that was performed using the hot wall low-pressure chemical vapour deposition (LPCVD) reactors at the Queensland Micro and Nanotechnology Center (QMNC), Griffith University and fabricated using the bulk-micromachining process. The MEMS CPS was operated at an extreme temperature up to 500°C and high external pressure at 5.0 MPa. The thermal hysteresis phenomenon that causes the deflection, strain and stress on the 3C-SiC diaphragm spontaneously influence the MEMS CPS performances. The differences of temperature, hysteresis, and repeatability test were presented to demonstrate the functionality of the MEMS packaged CPS. As expected, the output hysteresis has a low hysteresis (less than 0.05%) which has the hardness greater than the traditional silicon. By utilizing this low hysteresis, it was revealed that the MEMS packaged CPS has high repeatability and stability of the sensor.

  6. Clusters of galaxies associated with quasars. I. 3C 206

    Energy Technology Data Exchange (ETDEWEB)

    Ellingson, E.; Yee, H.K.C.; Green, R.F.; Kinman, T.D. (Steward Observatory, Tucson, AZ (USA); Montreal Universite (Canada); Kitt Peak National Observatory, Tucson, AZ (USA))

    1989-06-01

    Multislit spectroscopy and three-color CCD photometry of the galaxies in the cluster associated with the quasar 3C 206 (PKS 0837-12) at z = 0.198 are presented. This cluster is the richest environment of any low-redshift quasar observed in an Abell richness class 1 cluster. The cluster has a very flattened structure and a very concentrated core about the quasar. Most of the galaxies in this field have colors and luminosities consistent with normal galaxies at this redshift. The background-corrected blue fraction of galaxies is consistent with values for other rich clusters. The existence of several blue galaxies in the concentrated cluster core is an anomaly for a region of such high galaxy density, however, suggesting the absence of a substantial intracluster medium. This claim is supported by the Fanaroff-Riley (1974) class II morphology of the radio source. The velocity dispersion calculated from 11 spectroscopically confirmed cluster members is 500 + or - 110 km/s, which is slightly lower than the average for Abell class 1 clusters. A high frequency of interaction between the quasar host galaxy and cluster core members at low relative velocities, and a low intracluster gas pressure, may comprise a favorable environment for quasar activity. The properties of the cluster of galaxies associated with 3C 206 are consistent with this model. 59 refs.

  7. High Performance Green LEDs by Homoepitaxial

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, Christian; Schubert, E Fred

    2009-11-22

    This work's objective was the development of processes to double or triple the light output power from green and deep green (525 - 555 nm) AlGaInN light emitting diode (LED) dies within 3 years in reference to the Lumileds Luxeon II. The project paid particular effort to all aspects of the internal generation efficiency of light. LEDs in this spectral region show the highest potential for significant performance boosts and enable the realization of phosphor-free white LEDs comprised by red-green-blue LED modules. Such modules will perform at and outperform the efficacy target projections for white-light LED systems in the Department of Energy's accelerated roadmap of the SSL initiative.

  8. High performance compound semiconductor SPAD arrays

    Science.gov (United States)

    Harmon, Eric S.; Naydenkov, Mikhail; Bowling, Jared

    2016-05-01

    Aggregated compound semiconductor single photon avalanche diode (SPAD) arrays are emerging as a viable alternative to the silicon photomultiplier (SiPM). Compound semiconductors have the potential to surpass SiPM performance, potentially achieving orders of magnitude lower dark count rates and improved radiation hardness. New planar processing techniques have been developed to enable compound semiconductor SPAD devices to be produced with pixel pitches of 11 - 25 microns, with thousands of SPADs per array.

  9. Menhir: An Environment for High Performance Matlab

    Directory of Open Access Journals (Sweden)

    Stéphane Chauveau

    1999-01-01

    Full Text Available In this paper we present Menhir a compiler for generating sequential or parallel code from the Matlab language. The compiler has been designed in the context of using Matlab as a specification language. One of the major features of Menhir is its retargetability to generate parallel and sequential C or Fortran code. We present the compilation process and the target system description for Menhir. Preliminary performances are given and compared with MCC, the MathWorks Matlab compiler.

  10. High Performance Computing for Medical Image Interpretation

    Science.gov (United States)

    1993-10-01

    Ongerubriceerd All rights reserved.abtctOgr ried No part of this publication may bebtac neubier reproduced and/or published by print , photoprint...behalen miet de performance die verreist is in de medische kiniek, waardoor routinemnatig gebruik veelal tegen hoge personeels- kosten wordt uitgevoerd...166. D.R. Hush and B.G. Home (1993). "Progress in Supervised Neural Networks," IEEE Signal Process. Magazine , pp.8-39. S.H. Izen and E.M. Haacke (1990

  11. High performance flat plate solar collector

    Science.gov (United States)

    Lansing, F. L.; Reynolds, R.

    1976-01-01

    The potential use of porous construction is presented to achieve efficient heat removal from a power producing solid and is applied to solar air heaters. Analytical solutions are given for the temperature distribution within a gas-cooled porous flat plate having its surface exposed to the sun's energy. The extracted thermal energy is calculated for two different types of plate transparency. Results show the great improvement in performance obtained with porous flat plate collectors as compared with analogous nonporous types.

  12. High Performance Computing in Science and Engineering '99 : Transactions of the High Performance Computing Center

    CERN Document Server

    Jäger, Willi

    2000-01-01

    The book contains reports about the most significant projects from science and engineering of the Federal High Performance Computing Center Stuttgart (HLRS). They were carefully selected in a peer-review process and are showcases of an innovative combination of state-of-the-art modeling, novel algorithms and the use of leading-edge parallel computer technology. The projects of HLRS are using supercomputer systems operated jointly by university and industry and therefore a special emphasis has been put on the industrial relevance of results and methods.

  13. High Performance Computing in Science and Engineering '98 : Transactions of the High Performance Computing Center

    CERN Document Server

    Jäger, Willi

    1999-01-01

    The book contains reports about the most significant projects from science and industry that are using the supercomputers of the Federal High Performance Computing Center Stuttgart (HLRS). These projects are from different scientific disciplines, with a focus on engineering, physics and chemistry. They were carefully selected in a peer-review process and are showcases for an innovative combination of state-of-the-art physical modeling, novel algorithms and the use of leading-edge parallel computer technology. As HLRS is in close cooperation with industrial companies, special emphasis has been put on the industrial relevance of results and methods.

  14. High Performance Atomically Thin Flat Lenses

    CERN Document Server

    Lin, Han; Qiu, Chengwei; Jia, Baohua; Bao, Qiaoliang

    2016-01-01

    We experimentally demonstrate ultrathin flat lenses with a thickness of 7 {\\AA}, which corresponds to the fundamental physical limit of the thickness of the material, is fabricated in a large area, monolayer, CVD-prepared tungsten chalcogenides single crystals using the low-cost flexible laser writing method. The lenses apply the ultra-high refractive index to introduce abrupt amplitude modulation of the incident light to achieve three-dimensional (3D) focusing diffraction-limited resolution (0.5{\\lambda}) and a focusing efficiency as high as 31%. An analytical physical model based diffraction theory is derived to simulate the focusing process, which shows excellent agreement with the experimental results.

  15. High-performance commercial building facades

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eleanor; Selkowitz, Stephen; Bazjanac, Vladimir; Inkarojrit, Vorapat; Kohler, Christian

    2002-06-01

    This study focuses on advanced building facades that use daylighting, sun control, ventilation systems, and dynamic systems. A quick perusal of the leading architectural magazines, or a discussion in most architectural firms today will eventually lead to mention of some of the innovative new buildings that are being constructed with all-glass facades. Most of these buildings are appearing in Europe, although interestingly U.S. A/E firms often have a leading role in their design. This ''emerging technology'' of heavily glazed fagades is often associated with buildings whose design goals include energy efficiency, sustainability, and a ''green'' image. While there are a number of new books on the subject with impressive photos and drawings, there is little critical examination of the actual performance of such buildings, and a generally poor understanding as to whether they achieve their performance goals, or even what those goals might be. Even if the building ''works'' it is often dangerous to take a design solution from one climate and location and transport it to a new one without a good causal understanding of how the systems work. In addition, there is a wide range of existing and emerging glazing and fenestration technologies in use in these buildings, many of which break new ground with respect to innovative structural use of glass. It is unclear as to how well many of these designs would work as currently formulated in California locations dominated by intense sunlight and seismic events. Finally, the costs of these systems are higher than normal facades, but claims of energy and productivity savings are used to justify some of them. Once again these claims, while plausible, are largely unsupported. There have been major advances in glazing and facade technology over the past 30 years and we expect to see continued innovation and product development. It is critical in this process to be able to

  16. High performance image processing of SPRINT

    Energy Technology Data Exchange (ETDEWEB)

    DeGroot, T. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    This talk will describe computed tomography (CT) reconstruction using filtered back-projection on SPRINT parallel computers. CT is a computationally intensive task, typically requiring several minutes to reconstruct a 512x512 image. SPRINT and other parallel computers can be applied to CT reconstruction to reduce computation time from minutes to seconds. SPRINT is a family of massively parallel computers developed at LLNL. SPRINT-2.5 is a 128-node multiprocessor whose performance can exceed twice that of a Cray-Y/MP. SPRINT-3 will be 10 times faster. Described will be the parallel algorithms for filtered back-projection and their execution on SPRINT parallel computers.

  17. High performance flexible electronics for biomedical devices.

    Science.gov (United States)

    Salvatore, Giovanni A; Munzenrieder, Niko; Zysset, Christoph; Kinkeldei, Thomas; Petti, Luisa; Troster, Gerhard

    2014-01-01

    Plastic electronics is soft, deformable and lightweight and it is suitable for the realization of devices which can form an intimate interface with the body, be implanted or integrated into textile for wearable and biomedical applications. Here, we present flexible electronics based on amorphous oxide semiconductors (a-IGZO) whose performance can achieve MHz frequency even when bent around hair. We developed an assembly technique to integrate complex electronic functionalities into textile while preserving the softness of the garment. All this and further developments can open up new opportunities in health monitoring, biotechnology and telemedicine.

  18. HIGH PERFORMANCE CERIA BASED OXYGEN MEMBRANE

    DEFF Research Database (Denmark)

    2014-01-01

    The invention describes a new class of highly stable mixed conducting materials based on acceptor doped cerium oxide (CeO2-8 ) in which the limiting electronic conductivity is significantly enhanced by co-doping with a second element or co- dopant, such as Nb, W and Zn, so that cerium and the co...

  19. High performance carbon-carbon composites

    Indian Academy of Sciences (India)

    Lalit M Manocha

    2003-02-01

    Carbon-carbon composites rank first among ceramic composite materials with a spectrum of properties and applications in various sectors. These composites are made of fibres in various directions and carbonaceous polymers and hydrocarbons as matrix precursors. Their density and properties depend on the type and volume fraction of reinforcement, matrix precursor used and end heat treatment temperature. Composites made with thermosetting resins as matrix precursors possess low densities (1.55–1.75 g/cm3) and well-distributed microporosity whereas those made with pitch as the matrix precursor, after densification exhibit densities of 1.8–2.0 g/cm3 with some mesopores, and those made by the CVD technique with hydrocarbon gases, possess intermediate densities and matrices with close porosities. The former (resin-based) composites exhibit high flexural strength, low toughness and low thermal conductivity, whereas the latter (pitch- and CVD-based) can be made with very high thermal conductivity (400–700 W/MK) in the fibre direction. Carbon-carbon composites are used in a variety of sectors requiring high mechanical properties at elevated temperatures, good frictional properties for brake pads in high speed vehicles or high thermal conductivity for thermal management applications. However, for extended life applications, these composites need to be protected against oxidation either through matrix modification with Si, Zr, Hf etc. or by multilayer oxidation protection coatings consisting of SiC, silica, zircon etc.

  20. High-performance thresholding with adaptive equalization

    Science.gov (United States)

    Lam, Ka Po

    1998-09-01

    The ability to simplify an image whilst retaining such crucial information as shapes and geometric structures is of great importance for real-time image analysis applications. Here the technique of binary thresholding which reduces the image complexity has generally been regarded as one of the most valuable methods, primarily owing to its ease of design and analysis. This paper studies the state of developments in the field, and describes a radically different approach of adaptive thresholding. The latter employs the analytical technique of histogram normalization for facilitating an optimal `contrast level' of the image under consideration. A suitable criterion is also developed to determine the applicability of the adaptive processing procedure. In terms of performance and computational complexity, the proposed algorithm compares favorably to five established image thresholding methods selected for this study. Experimental results have shown that the new algorithm outperforms these methods in terms of a number of important errors measures, including a consistently low visual classification error performance. The simplicity of design of the algorithm also lends itself to efficient parallel implementations.

  1. High Performance, Three-Dimensional Bilateral Filtering

    Energy Technology Data Exchange (ETDEWEB)

    Bethel, E. Wes

    2008-06-05

    Image smoothing is a fundamental operation in computer vision and image processing. This work has two main thrusts: (1) implementation of a bilateral filter suitable for use in smoothing, or denoising, 3D volumetric data; (2) implementation of the 3D bilateral filter in three different parallelization models, along with parallel performance studies on two modern HPC architectures. Our bilateral filter formulation is based upon the work of Tomasi [11], but extended to 3D for use on volumetric data. Our three parallel implementations use POSIX threads, the Message Passing Interface (MPI), and Unified Parallel C (UPC), a Partitioned Global Address Space (PGAS) language. Our parallel performance studies, which were conducted on a Cray XT4 supercomputer and aquad-socket, quad-core Opteron workstation, show our algorithm to have near-perfect scalability up to 120 processors. Parallel algorithms, such as the one we present here, will have an increasingly important role for use in production visual analysis systems as the underlying computational platforms transition from single- to multi-core architectures in the future.

  2. HIGH PERFORMANCE PHOTOGRAMMETRIC PROCESSING ON COMPUTER CLUSTERS

    Directory of Open Access Journals (Sweden)

    V. N. Adrov

    2012-07-01

    Full Text Available Most cpu consuming tasks in photogrammetric processing can be done in parallel. The algorithms take independent bits as input and produce independent bits as output. The independence of bits comes from the nature of such algorithms since images, stereopairs or small image blocks parts can be processed independently. Many photogrammetric algorithms are fully automatic and do not require human interference. Photogrammetric workstations can perform tie points measurements, DTM calculations, orthophoto construction, mosaicing and many other service operations in parallel using distributed calculations. Distributed calculations save time reducing several days calculations to several hours calculations. Modern trends in computer technology show the increase of cpu cores in workstations, speed increase in local networks, and as a result dropping the price of the supercomputers or computer clusters that can contain hundreds or even thousands of computing nodes. Common distributed processing in DPW is usually targeted for interactive work with a limited number of cpu cores and is not optimized for centralized administration. The bottleneck of common distributed computing in photogrammetry can be in the limited lan throughput and storage performance, since the processing of huge amounts of large raster images is needed.

  3. Analysis list: Nr3c1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Nr3c1 Adipocyte,Blood,Breast,Embryo,Embryonic fibroblast,Liver,Neural + mm9 http://...dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr3c1.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr3c1....5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr3c1.10.tsv http://dbarchive.bioscie...ncedbc.jp/kyushu-u/mm9/colo/Nr3c1.Adipocyte.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Nr3c1....Blood.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Nr3c1.Breast.tsv,http

  4. 锰掺杂对锂离子电池正极材料Li3V2(PO4)3/C性能的影响%Effect of Mn-doping on performance of Li3V2(PO4)3/C cathode material for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    翟静; 赵敏寿; 王丹丹

    2011-01-01

    采用溶胶-凝胶法合成Li3V2-2/3xMnx(PO4)3(0≤x≤0.12).采用XRD、SEM、XPS、恒流充放电和电化学阻抗谱(EIS)研究Mn掺杂对Li3v2(PO4)3/C结构和电化学性能的影响.XRD研究表明:掺杂少量的Mn2+不会影响材料的结构,所有样品均具有单一相态的单斜结构(P21/n空间群).XPS分析表明:在Li3V1.94Mn0.09(PO4)3/C中,V和Mn的化合价分别为+3和+2,原料中的柠檬酸在煅烧过程中分解成C而残留在Li3V1.94Mn0.09(PO4)3/C中.电化学测试表明:掺杂Mn改善了电极材料的循环性能和倍率性能,正极材料Li3V1.94Mn0.09(PO4)3/C表现出最好的循环稳定性和倍率性能.在40 mA/g的放电电流密度下,循环100次后,Li3V1.94Mn0.09(PO4)3/C的放电容量从158.8mA·h/g衰减到120.5 mA·h/g,容量保持率为75.9%,而未掺杂样品的放电容量从164.2 mA·h/g衰减到72.6 mA·h/g,容量保持率为44.2%.当放电电流密度增加到lC时,Li3V1.94Mn0.09(PO4)3/C的初始放电容量仍能达到146.4mA·h/g,循环100次后,放电容量保持为107.5 mA·h/g.EIS测试表明,掺杂适量的Mn2+减小了电荷转移阻抗,这有利于Li+的脱嵌.%Li3V2-2/3xMnx(PO4)3(0≤x≤0.12) powders were synthesized by sol-gel method. The effect of Mn2+-doping on the structure and electrochemical performances of Li3V2(PO4)3/C was characterized by XRD,SEM,XPS,galvanostatic charge/discharge and electrochemical impedance spectroscopy(ElS). The XRD study shows that a small amount of Mn2+-doped does not alter the structure of Li3V2(PO4)3/C materials,and all Mn2+-doped samples are of pure single phase with a monoclinic structure (space group P21/n).The XPS analysis indicates that valences state of V and Mn are +3 and +2 in Li3V1.94Mn0.09(PO4)3/C,respectively,and the citric acid in raw materials was decomposed into carbon during calcination,and residual carbon exists in Li3V1.94Mn0.09(PO4)/C. The results of electrochemical measurements show that Mn2+-doping can improve the cyclic stability and rate

  5. High-Performance Synthetic Fibers for Composites

    Science.gov (United States)

    1992-04-01

    required wastewater treatment . In short, this new process can easily produce the current standard high-quality precursor fiber, but it also has the...FMI Composites LTD); Formation of fibergLass\\preform for composite coupling shaft; Undulating ribbon structure of graphene layers for a PAN-based c...ongoing research and development in areas that are of general importance to fiber science and technology (surface properties and treatments , fiber-matrix

  6. Noise of High Performance Aircraft at Afterburner

    Science.gov (United States)

    2016-05-04

    Mathematics Florida State University Email: tam@math.fsu.edu Grant Monitor Dr. John Spyropoulous Email: John.Spyropoulous@jsf.mil...of equations (1) and (2). Obviously, the computed spectrum is unacceptable. It is overwhelmed by spurious high frequency oscillations. Figure 2...reasoning suggests that we may, as a first approximation, insert a boxcar window function in the integral of equation (4). That is, equation (4) is

  7. High performance cyclo olefin polymer ZEONEX

    Science.gov (United States)

    Konishi, Yuichiro; Sawaguchi, Taichi; Kubomura, Kyoichi; Minami, Koji

    2005-09-01

    Zeon Corporation developed quite new optical plastic Cyclo Olefin Polymer; COP(ZEONEX) with own technology in 1990 then started sales for ZEONEX for optical application with its very unique properties such as low birefringence, low water absorption, high glass-transition temperature 136 °C and high light transmission etc. Currently, ZEONEX is well known in optical market and used widely as optical plastic for pick up lens and other many kinds of optical parts for laser beam printer and digital camera. Addition to those ZEONEX grades, in last year, Zeon Corporation developed a new ZEONEX grade called ZEONEX340R, which was designed for blue laser devices requiring more severe specification. ZEONEX340R has high transmission at 405nm which is used laser wavelength for Blu-ray Disk / HD-DVD as well as enough durability under exposure of 405nm laser, addition to those new properties, keeps other optical properties such as low birefringence and very low water absorption.

  8. HIGH TEMPERATURE OXIDATION PERFORMANCE OF ALUMINIDE COATINGS

    Energy Technology Data Exchange (ETDEWEB)

    Pint, B.A.; Zhang, Y.; Haynes, J.A.; Wright, I.G.

    2003-04-22

    In order to determine the potential benefits and limitations of aluminide coatings, coatings made by chemical vapor deposition (CVD) on Fe- and Ni-base alloy substrates are being evaluated in various high-temperature environments. Testing of coatings on representative ferritic (Fe-9Cr-1Mo) and austenitic (type 304L stainless steel) alloys has found that high frequency thermal cycling (1h cycle time) can significantly degrade the coating. Based on comparison with similar specimens with no thermal cycling or a longer cycle time (100h), this degradation was not due to Al loss from the coating but most likely because of the thermal expansion mismatch between the coating and the substrate. Several coated Ni-base alloys were tested in a high pressure (20atm) steam-CO2 environment for the ZEST (zero-emission steam turbine) program. Coated specimens showed less mass loss than the uncoated specimens after 1000h at 900 C and preliminary characterization examined the post-test coating structure and extent of attack.

  9. High temperature performance of polymer composites

    CERN Document Server

    Keller, Thomas

    2014-01-01

    The authors explain the changes in the thermophysical and thermomechanical properties of polymer composites under elevated temperatures and fire conditions. Using microscale physical and chemical concepts they allow researchers to find reliable solutions to their engineering needs on the macroscale. In a unique combination of experimental results and quantitative models, a framework is developed to realistically predict the behavior of a variety of polymer composite materials over a wide range of thermal and mechanical loads. In addition, the authors treat extreme fire scenarios up to more than 1000°C for two hours, presenting heat-protection methods to improve the fire resistance of composite materials and full-scale structural members, and discuss their performance after fire exposure. Thanks to the microscopic approach, the developed models are valid for a variety of polymer composites and structural members, making this work applicable to a wide audience, including materials scientists, polymer chemist...

  10. Information processing among high-performance managers

    Directory of Open Access Journals (Sweden)

    S.C. Garcia-Santos

    2010-01-01

    Full Text Available The purpose of this study was to evaluate the information processing of 43 business managers with a professional superior performance. The theoretical framework considers three models: the Theory of Managerial Roles of Henry Mintzberg, the Theory of Information Processing, and Process Model Response to Rorschach by John Exner. The participants have been evaluated by Rorschach method. The results show that these managers are able to collect data, evaluate them and establish rankings properly. At same time, they are capable of being objective and accurate in the problems assessment. This information processing style permits an interpretation of the world around on basis of a very personal and characteristic processing way or cognitive style.

  11. Photoluminescence Properties of Nanocrystalline 3C-SiC Films

    Institute of Scientific and Technical Information of China (English)

    YU Wei; LU Xue-qin; LU Wan-bing; HAN Li; FU Guang-sheng

    2006-01-01

    Nanocrystalline (nc) 3C-SiC films on the Si substrate were prepared by the helicon wave plasma enhanced chemical vapor deposition (HW-PECVD) technique. With the SiH4-CH4 gas flow ratio changing, the films exhibit different photoluminescence (PL) characteristics. Under the stoichiometric condition, the PL peak redshift from 470 nm to 515 nm is detected with the increase of excitation wavelength, which can be attributed to the quantum confinement effect radiation of 3C-SiC nanocrystals of different sizes. However, the appearance of an additional PL band at 436 nm in Si-rich film might be sourced back to the excess of Si defect centers in it. This is also the case for C-rich film for its PL band lying at 570 nm. The results above quoted indicate an important influence of gas flow ratio on the PL properties of the SiC films providing an effective guidance for analyzing the luminescence mechanism and exploring the high-efficiency light emission of the SiC films.

  12. The Multifrequency Campaign on 3C 279 in January 2006

    CERN Document Server

    Collmar, W; Krichbaum, T P; Agudo, I; Bottacini, E; Bremer, M; Burwitz, V; Cuccchiara, A; Grupe, D; Gurwell, M

    2010-01-01

    We present the results of a multifrequency campaign from radio to hard X-ray energies on the blazar 3C 279 during an optical high-state in January 2006. We give the observational results (multifrequency light curves and spectra) and compile an SED. This complements an SED from an optical low-state in June 2003. Surprisingly the two SEDs differ only in their high-energy synchrotron emission (near-IR - UV), while the low-energy inverse-Compton emission (X- to Gamma-rays) remained unchanged. By interpreting with a steady-state leptonic emission model, the variability among the SED can be reproduced by a change solely of the low-energy cutoff of the relativistic electron distribution. In an internal shock model for blazar emission, such a change could e.g. achieved through a varying relative Lorentz factor of colliding shells producing internal shocks in the jet.

  13. High Performance Calcium Titanate Nanoparticle ER Fluids

    Science.gov (United States)

    Wang, Xuezhao; Shen, Rong; Wen, Weijia; Lu, Kunquan

    A type of calcium titanate (CTO) nanoparticles was synthesized by means of wet chemical method [1] without coating on the particles. The CTO/silicone oil ER fluid exhibits excellent electrorheological properties: high shear stress (~50-100 kPa) under dc electric field, a low current density (less than 2μA/cm2 at 5kV/mm), and long term stability against sedimentation. Although there are not special additives in the ER fluids, it is found from the chemical analysis that a trace of alkyl group, hydroxyl group, carbonyl group and some ions is remained in the particles which may dominate the ER response.

  14. High Performance Polymer Memory and Its Formation

    Science.gov (United States)

    2007-04-26

    bio-inorganic hybrid nanocomposite embedded in a polyvinyl alcohol matrix between two aluminum electrodes. Figu rete PtMnti of dvi-e L - -2rwJ scan...The most common candidate for the acceptor material is [6,6]-phenyl C61- butyric acid methyl ester (PCBM).23 On the other hand, several small molecules...community, is regioregular poly(3-hexylthiophene) or RR-P3HT. Highly efficient solar cells based on BHJ of P3HT with [6,6]-phenyl-C 61- butyric acid methyl

  15. Very High Performance Organic Photonic Devices

    Science.gov (United States)

    2008-01-15

    warta,.w. Stehie, R.& Karl, N, Ultraput. high moability organic pluonocondluctors. Appi Phys. A36. cold weld. Finally, the strike layer between the...Roman, and 0. Inganas. J1. AppI . Phys. C. Silva. Phys. Rev. Lett. 92, 247402 (2004). 86. 487 (1999). 36T Offermans, P. A. van Hal, S. C. J. Meskers. M... AppI . Phys. 97. 103706 093502( (2005). (2005). 38K. L. Mutolo. E. 1. Mayo, B. P. Rand, S. R. Forre%t. and M. E. 27 . Riedel. J. Parisi. V. Dyakonov. L

  16. High-performance silicon nanowire bipolar phototransistors

    Science.gov (United States)

    Tan, Siew Li; Zhao, Xingyan; Chen, Kaixiang; Crozier, Kenneth B.; Dan, Yaping

    2016-07-01

    Silicon nanowires (SiNWs) have emerged as sensitive absorbing materials for photodetection at wavelengths ranging from ultraviolet (UV) to the near infrared. Most of the reports on SiNW photodetectors are based on photoconductor, photodiode, or field-effect transistor device structures. These SiNW devices each have their own advantages and trade-offs in optical gain, response time, operating voltage, and dark current noise. Here, we report on the experimental realization of single SiNW bipolar phototransistors on silicon-on-insulator substrates. Our SiNW devices are based on bipolar transistor structures with an optically injected base region and are fabricated using CMOS-compatible processes. The experimentally measured optoelectronic characteristics of the SiNW phototransistors are in good agreement with simulation results. The SiNW phototransistors exhibit significantly enhanced response to UV and visible light, compared with typical Si p-i-n photodiodes. The near infrared responsivities of the SiNW phototransistors are comparable to those of Si avalanche photodiodes but are achieved at much lower operating voltages. Compared with other reported SiNW photodetectors as well as conventional bulk Si photodiodes and phototransistors, the SiNW phototransistors in this work demonstrate the combined advantages of high gain, high photoresponse, low dark current, and low operating voltage.

  17. Liquid argon calorimeter performance at high rates

    CERN Document Server

    Seifert, F; The ATLAS collaboration

    2012-01-01

    The expected increase of luminosity at HL-LHC by a factor of ten with respect to LHC luminosities has serious consequences for the signal reconstruction, radiation hardness requirements and operations of the ATLAS liquid argon calorimeters in the endcap, respectively forward region. Small modules of each type of calorimeter have been built and exposed to a high intensity proton beam of 50 GeV at IHEP/Protvino. The beam is extracted via the bent crystal technique, offering the unique opportunity to cover intensities ranging from $10^6$ p/s up to $10^{12}$ p/s. This exceeds the deposited energy per time expected at HL-LHC by more than a factor of 100. The correlation between beam intensity and the read-out signal has been studied. The data show clear indications of pulse shape distortion due to the high ionization build-up, in agreement with MC expectations. This is also confirmed from the dependence of the HV currents on beam intensity.

  18. Liquid Argon Calorimeter performance at High Rates

    CERN Document Server

    Seifert, F; The ATLAS collaboration

    2013-01-01

    The expected increase of luminosity at HL-LHC by a factor of ten with respect to LHC luminosities has serious consequences for the signal reconstruction, radiation hardness requirements and operations of the ATLAS liquid argon calorimeters in the endcap, respectively forward region. Small modules of each type of calorimeter have been built and exposed to a high intensity proton beam of 50 GeV at IHEP/Protvino. The beam is extracted via the bent crystal technique, offering the unique opportunity to cover intensities ranging from $10^6$ p/s up to $3\\cdot10^{11}$ p/s. This exceeds the deposited energy per time expected at HL-LHC by more than a factor of 100. The correlation between beam intensity and the read-out signal has been studied. The data show clear indications of pulse shape distortion due to the high ionization build-up, in agreement with MC expectations. This is also confirmed from the dependence of the HV currents on beam intensity.

  19. A high performance field-reversed configuration

    Energy Technology Data Exchange (ETDEWEB)

    Binderbauer, M. W.; Tajima, T.; Steinhauer, L. C.; Garate, E.; Tuszewski, M.; Smirnov, A.; Gota, H.; Barnes, D.; Deng, B. H.; Thompson, M. C.; Trask, E.; Yang, X.; Putvinski, S.; Rostoker, N.; Andow, R.; Aefsky, S.; Bolte, N.; Bui, D. Q.; Ceccherini, F.; Clary, R. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); and others

    2015-05-15

    Conventional field-reversed configurations (FRCs), high-beta, prolate compact toroids embedded in poloidal magnetic fields, face notable stability and confinement concerns. These can be ameliorated by various control techniques, such as introducing a significant fast ion population. Indeed, adding neutral beam injection into the FRC over the past half-decade has contributed to striking improvements in confinement and stability. Further, the addition of electrically biased plasma guns at the ends, magnetic end plugs, and advanced surface conditioning led to dramatic reductions in turbulence-driven losses and greatly improved stability. Together, these enabled the build-up of a well-confined and dominant fast-ion population. Under such conditions, highly reproducible, macroscopically stable hot FRCs (with total plasma temperature of ∼1 keV) with record lifetimes were achieved. These accomplishments point to the prospect of advanced, beam-driven FRCs as an intriguing path toward fusion reactors. This paper reviews key results and presents context for further interpretation.

  20. Analysis of silt cavitation erosion resistance of Cr,C2/NiCr coating prepared by high velocity oxy-fuel thermal spraying%超音速火焰喷涂Cr3C2/NiCr涂层抗加沙空蚀性分析

    Institute of Scientific and Technical Information of China (English)

    王倩; 吴玉萍; 李改叶; 郭文敏

    2013-01-01

    采用HVOF技术在1Cr18Ni9Ti不锈钢基体上制备了Cr3C2/NiCr涂层,借助XRD,TEM,SEM等方法分析了涂层的组织形貌及相组成.以1Cr18Ni9Ti奥氏体不锈钢作为对比材料,用磁致伸缩空蚀仪配备扬沙装置测试了涂层在清水以及含沙水中抗空蚀性能.结果表明,涂层呈层状结构,含有未熔颗粒和少量孔隙,涂层由Cr3C2,Cr7C3,Cr23C6及NiCr等相组成;在清水试验中,1Cr18Ni9Ti不锈钢抗空蚀性能良好,与空蚀过程中1Cr18Ni9Ti奥氏体不锈钢产生加工硬化有直接关系;在含沙40 kg/m3试验水中,Cr3C2/NiCr涂层呈现出较好的抗空蚀性能,与涂层自身相组成以及较高硬度有关.Cr3C2/NiCr涂层破坏总是从孔隙等薄弱环节开始,而1Cr18Ni9Ti奥氏体不锈钢的破坏起始于晶界和孪晶界.%A Cr3C2/NiCr coating was prepared on 1Cr18Ni9Ti stainless steel by high velocity oxy-fuel (HVOF) thermal spraying. Phases and microstructures of the coating were analyzed by X-ray diffraction (XRD) , transmission electron microscope (TEM) and scanning election microscopy (SEM) , respectively. The cavitation erosion resistance and silt erosion resistance of the coating were evaluated under two experimental conditions (fresh water and water contained fine silt) , and compared with hydro machine material lCrl8Ni9Ti stainless steel. The result shows that the coating shows a layered structure and contains un-melted particles and some pores. The phases of the coating are composed of Cr3C2, Cr7C3, Cr23 C6 and NiCr. The 1Cr18Ni9Ti stainless steel produces the work hardening, which results in the resistance to cavitation erosion. The Cr3C2/NiCr coating exhibits significantly higher microhardness than 1Cr18Ni9Ti stainless steel, which leads to the resistance to silt erosion of the coating. The mass loss of the coating usually happens at the edges of the pores while the cavitation damage of the 1Cr18Ni9Ti stainless steel happens at the grain boundary and twin boundary.

  1. High performance magnet power supply optimization

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, L.T.

    1988-01-01

    The power supply system for the joint LBL--SLAC proposed accelerator PEP provides the opportunity to take a fresh look at the current techniques employed for controlling large amounts of dc power and the possibility of using a new one. A basic requirement of +- 100 ppM regulation is placed on the guide field of the bending magnets and quadrupoles placed around the 2200 meter circumference of the accelerator. The optimization questions to be answered by this paper are threefold: Can a firing circuit be designed to reduce the combined effects of the harmonics and line voltage combined effects of the harmonics and line voltage unbalance to less than 100 ppM in the magnet field. Given the ambiguity of the previous statement, is the addition of a transistor bank to a nominal SCR controlled system the way to go or should one opt for an SCR chopper system running at 1 KHz where multiple supplies are fed from one large dc bus and the cost--performance evaluation of the three possible systems.

  2. Development of high performance hybrid rocket fuels

    Science.gov (United States)

    Zaseck, Christopher R.

    . In order to examine paraffin/additive combustion in a motor environment, I conducted experiments on well characterized aluminum based additives. In particular, I investigate the influence of aluminum, unpassivated aluminum, milled aluminum/polytetrafluoroethylene (PTFE), and aluminum hydride on the performance of paraffin fuels for hybrid rocket propulsion. I use an optically accessible combustor to examine the performance of the fuel mixtures in terms of characteristic velocity efficiency and regression rate. Each combustor test consumes a 12.7 cm long, 1.9 cm diameter fuel strand under 160 kg/m 2s of oxygen at up to 1.4 MPa. The experimental results indicate that the addition of 5 wt.% 30 mum or 80 nm aluminum to paraffin increases the regression rate by approximately 15% compared to neat paraffin grains. At higher aluminum concentrations and nano-scale particles sizes, the increased melt layer viscosity causes slower regression. Alane and Al/PTFE at 12.5 wt.% increase the regression of paraffin by 21% and 32% respectively. Finally, an aging study indicates that paraffin can protect air and moisture sensitive particles from oxidation. The opposed burner and aluminum/paraffin hybrid rocket experiments show that additives can alter bulk fuel properties, such as viscosity, that regulate entrainment. The general effect of melt layer properties on the entrainment and regression rate of paraffin is not well understood. Improved understanding of how solid additives affect the properties and regression of paraffin is essential to maximize performance. In this document I investigate the effect of melt layer properties on paraffin regression using inert additives. Tests are performed in the optical cylindrical combustor at ˜1 MPa under a gaseous oxygen mass flux of ˜160 kg/m2s. The experiments indicate that the regression rate is proportional to mu0.08rho 0.38kappa0.82. In addition, I explore how to predict fuel viscosity, thermal conductivity, and density prior to testing

  3. High-Performance Energy Applications and Systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Barton [Univ. of Wisconsin, Madison, WI (United States)

    2014-01-01

    The Paradyn project has a history of developing algorithms, techniques, and software that push the cutting edge of tool technology for high-end computing systems. Under this funding, we are working on a three-year agenda to make substantial new advances in support of new and emerging Petascale systems. The overall goal for this work is to address the steady increase in complexity of these petascale systems. Our work covers two key areas: (1) The analysis, instrumentation and control of binary programs. Work in this area falls under the general framework of the Dyninst API tool kits. (2) Infrastructure for building tools and applications at extreme scale. Work in this area falls under the general framework of the MRNet scalability framework. Note that work done under this funding is closely related to work done under a contemporaneous grant, “Foundational Tools for Petascale Computing”, SC0003922/FG02-10ER25940, UW PRJ27NU.

  4. High-Performance Energy Applications and Systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Barton

    2014-05-19

    The Paradyn project has a history of developing algorithms, techniques, and software that push the cutting edge of tool technology for high-end computing systems. Under this funding, we are working on a three-year agenda to make substantial new advances in support of new and emerging Petascale systems. The overall goal for this work is to address the steady increase in complexity of these petascale systems. Our work covers two key areas: (1) The analysis, instrumentation and control of binary programs. Work in this area falls under the general framework of the Dyninst API tool kits. (2) Infrastructure for building tools and applications at extreme scale. Work in this area falls under the general framework of the MRNet scalability framework. Note that work done under this funding is closely related to work done under a contemporaneous grant, “Foundational Tools for Petascale Computing”, SC0003922/FG02-10ER25940, UW PRJ27NU.

  5. High Dynamic Performance Nonlinear Source Emulator

    DEFF Research Database (Denmark)

    Nguyen-Duy, Khiem; Knott, Arnold; Andersen, Michael A. E.

    2016-01-01

    As research and development of renewable and clean energy based systems is advancing rapidly, the nonlinear source emulator (NSE) is becoming very essential for testing of maximum power point trackers or downstream converters. Renewable and clean energy sources play important roles in both...... terrestrial and nonterrestrial applications. However, most existing NSEs have only been concerned with simulating energy sources in terrestrial applications, which may not be fast enough for testing of nonterrestrial applications. In this paper, a high-bandwidth NSE is developed that is able to simulate...... change in the input source but also to a load step between nominal and open circuit. Moreover, all of these operation modes have a very fast settling time of only 10 μs, which is hundreds of times faster than that of existing works. This attribute allows for higher speed and a more efficient maximum...

  6. Leptonic and Lepto-Hadronic Modeling of the Nov. 2010 flare from 3C 454.3

    CERN Document Server

    Diltz, Christopher S

    2016-01-01

    In this study, we use a one-zone leptonic and a lepto-hadronic model to investigate the multi-wavelength emission and the prominent flare of the flat spectrum radio quasar 3C 454.3 in Nov 2010. We perform a parameter study with both models to obtain broadband fits to the spectral energy distribution of 3C 454.3. Starting with the baseline parameters obtained from the fits, we then investigate different flaring scenarios for both models to explain an extreme outburst and spectral hardening of 3C 454.3 that occurred in Nov 2010. We find that the one zone lepto-hadronic model can successfully explain both the broadband multi-wavelength spectral energy distribution and light curves in the optical R, Swift XRT and Fermi gamma-ray bandpasses for 3C 454.3 during quiescence and the peak of the Nov. 2010 flare. We also find that the one-zone leptonic model produces poor fits to the broadband spectra in the X-ray and high energy gamma-ray band passes for the Nov. 2010 flare.

  7. Leptonic and Lepto-Hadronic Modeling of the 2010 November Flare from 3C 454.3

    Science.gov (United States)

    Diltz, C.; Böttcher, M.

    2016-07-01

    In this study, we use a one-zone leptonic and a lepto-hadronic model to investigate the multi-wavelength emission and prominent flare of the flat spectrum radio quasar 3C 454.3 in 2010 November. We perform a parameter study with both models to obtain broadband fits to the spectral energy distribution (SED) of 3C 454.3. Starting with the baseline parameters obtained from the fits, we then investigate different flaring scenarios for both models to explain an extreme outburst and spectral hardening of 3C 454.3 that occurred in 2010 November. We find that the one-zone lepto-hadronic model can successfully explain both the broadband multi-wavelength SED and light curves in the optical R, Swift X-Ray Telescope, and Fermi γ-ray band passes for 3C 454.3 during quiescence and the peak of the 2010 November flare. We also find that the one-zone leptonic model produces poor fits to the broadband spectra in the X-ray and high-energy γ-ray band passes for the 2010 November flare.

  8. Performance evaluation of high speed compressors for high speed multipliers

    Directory of Open Access Journals (Sweden)

    Nirlakalla Ravi

    2011-01-01

    Full Text Available This paper describes high speed compressors for high speed parallel multipliers like Booth Multiplier, Wallace Tree Multiplier in Digital Signal Processing (DSP. This paper presents 4-3, 5-3, 6-3 and 7-3 compressors for high speed multiplication. These compressors reduce vertical critical path more rapidly than conventional compressors. A 5-3 conventional compressor can take four steps to reduce bits from 5 to 3, but the proposed 5-3 takes only 2 steps. These compressors are simulated with H-Spice at a temperature of 25°C at a supply voltage 2.0V using 90nm MOSIS technology. The Power, Delay, Power Delay Product (PDP and Energy Delay Product (EDP of the compressors are calculated to analyze the total propagation delay and energy consumption. All the compressors are designed with half adder and full Adders only.

  9. High Performance Multiple Stream Data Transfer

    Institute of Scientific and Technical Information of China (English)

    F.Rademakers; P.Saiz; 等

    2001-01-01

    The ALICE detector at LHC( CERN),will record raw data at a rate of 1.2 Gigabytes per second.Trying to analyse all this data at CRN will not be feasible.As originally proposed by the MONARC project,dta collected at CERN will be transferred to remote centres to use their computing infrastructure,The remote centres will reconstruct and analyse the events.and make available the results.Therefore high-rate data transfer between computing centres(Tiers)will become of paramount importance.This paper will present several tests that have been made between CERN and remote centres in Padova(Italy),Torino(Italy),Catania(Italy),Lyon(France),Ohio(United States),Warsaw(Poland)and Calcutta( India),These tests consisted,in a first stage,of sending raw data from CERN to the remote centres and back,using a ftp method that allows connections of several streams at the same time.Thanks to these multiple streams,it is possilble to increase the rate at which the data is transferred.While several "multiple stream ftp solutions" already exist,our method is based on a parallel socket implementation which allows,besides files,also objects(or any large message)to be send in parallel.A prototype will be presented able to manage different transfers.This is the first step of a system to be implemented that will be able to take care of the connections with the remote centres to exchange data and monitor the status of the transfer.

  10. Poliovirus protease 3C(pro) kills cells by apoptosis.

    Science.gov (United States)

    Barco, A; Feduchi, E; Carrasco, L

    2000-01-20

    The tetracycline-based Tet-Off expression system has been used to analyze the effects of poliovirus protease 3C(pro) on human cells. Stable HeLa cell clones that express this poliovirus protease under the control of an inducible, tightly regulated promoter were obtained. Tetracycline removal induces synthesis of 3C protease, followed by drastic morphological alterations and cellular death. Degradation of cellular DNA in nucleosomes and generation of apoptotic bodies are observed from the second day after 3C(pro) induction. The cleavage of poly(ADP-ribose) polymerase, an enzyme involved in DNA repair, occurs after induction of 3C(pro), indicating caspase activation by this poliovirus protease. The 3C(pro)-induced apoptosis is blocked by the caspase inhibitor z-VAD-fmk. Our findings suggest that the protease 3C is responsible for triggering apoptosis in poliovirus-infected cells by a mechanism that involves caspase activation.

  11. Vortices in high-performance high-temperature superconductors

    Science.gov (United States)

    Kwok, Wai-Kwong; Welp, Ulrich; Glatz, Andreas; Koshelev, Alexei E.; Kihlstrom, Karen J.; Crabtree, George W.

    2016-11-01

    The behavior of vortex matter in high-temperature superconductors (HTS) controls the entire electromagnetic response of the material, including its current carrying capacity. Here, we review the basic concepts of vortex pinning and its application to a complex mixed pinning landscape to enhance the critical current and to reduce its anisotropy. We focus on recent scientific advances that have resulted in large enhancements of the in-field critical current in state-of-the-art second generation (2G) YBCO coated conductors and on the prospect of an isotropic, high-critical current superconductor in the iron-based superconductors. Lastly, we discuss an emerging new paradigm of critical current by design—a drive to achieve a quantitative correlation between the observed critical current density and mesoscale mixed pinning landscapes by using realistic input parameters in an innovative and powerful large-scale time dependent Ginzburg-Landau approach to simulating vortex dynamics.

  12. Vortices in high-performance high-temperature superconductors.

    Science.gov (United States)

    Kwok, Wai-Kwong; Welp, Ulrich; Glatz, Andreas; Koshelev, Alexei E; Kihlstrom, Karen J; Crabtree, George W

    2016-11-01

    The behavior of vortex matter in high-temperature superconductors (HTS) controls the entire electromagnetic response of the material, including its current carrying capacity. Here, we review the basic concepts of vortex pinning and its application to a complex mixed pinning landscape to enhance the critical current and to reduce its anisotropy. We focus on recent scientific advances that have resulted in large enhancements of the in-field critical current in state-of-the-art second generation (2G) YBCO coated conductors and on the prospect of an isotropic, high-critical current superconductor in the iron-based superconductors. Lastly, we discuss an emerging new paradigm of critical current by design-a drive to achieve a quantitative correlation between the observed critical current density and mesoscale mixed pinning landscapes by using realistic input parameters in an innovative and powerful large-scale time dependent Ginzburg-Landau approach to simulating vortex dynamics.

  13. High Performance Liquid Chromatography/Video Fluorometry. Part II. Applications.

    Science.gov (United States)

    1981-09-30

    HIGH PERFORMANCE LIQUID CHROMATOGRAPHY /VIDEO FLUOROMETRY. PART...REP«T_N&:-ŗ/ High Performance Liquid Chromatography /Video Fluorometry» Part II. Applications« by | Dennis C./Shelly* Michael P./Vogarty and...Data EnlirtdJ REPORT DOCUMENTATION PAGE t. REPORT NUMBER 2 GOVT ACCESSION NO 4. T1TI.F (and Submit) lP-^fffsyva High Performance Liquid Chromatography

  14. Development of Synthetic Spider Silk Fibers for High Performance Applications

    Science.gov (United States)

    2013-08-08

    REPORT Development of Synthetic Spider Silk Fibers for High Performance Applications 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: The overall goal of...this project is to demonstrate the feasibility of synthetic production of high-performance spider silk fibers for use in next-generation automotives...Z39.18 - 31-May-2013 Development of Synthetic Spider Silk Fibers for High Performance Applications Report Title ABSTRACT The overall goal of this

  15. High Performance Monopropellants for Future Planetary Ascent Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Inc. proposes to design, develop, and demonstrate, a novel high performance monopropellant for application in future planetary ascent vehicles. Our...

  16. High Performance Low Mass Nanowire Enabled Heatpipe Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Heat pipes are widely used for passive, two-phase electronics cooling. As advanced high power, high performance electronics in space based and terrestrial...

  17. Innovative Deep Throttling, High Performance Injector Concept Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Science and Technology Applications, LLC's (STA) vision for a versatile space propulsion system is a highly throttleable, high performance, and cost effective Liquid...

  18. High Performance Computing in Science and Engineering '08 : Transactions of the High Performance Computing Center

    CERN Document Server

    Kröner, Dietmar; Resch, Michael

    2009-01-01

    The discussions and plans on all scienti?c, advisory, and political levels to realize an even larger “European Supercomputer” in Germany, where the hardware costs alone will be hundreds of millions Euro – much more than in the past – are getting closer to realization. As part of the strategy, the three national supercomputing centres HLRS (Stuttgart), NIC/JSC (Julic ¨ h) and LRZ (Munich) have formed the Gauss Centre for Supercomputing (GCS) as a new virtual organization enabled by an agreement between the Federal Ministry of Education and Research (BMBF) and the state ministries for research of Baden-Wurttem ¨ berg, Bayern, and Nordrhein-Westfalen. Already today, the GCS provides the most powerful high-performance computing - frastructure in Europe. Through GCS, HLRS participates in the European project PRACE (Partnership for Advances Computing in Europe) and - tends its reach to all European member countries. These activities aligns well with the activities of HLRS in the European HPC infrastructur...

  19. Complement C3c as a Biomarker in Heart Failure

    Directory of Open Access Journals (Sweden)

    A. Frey

    2013-01-01

    Full Text Available Introduction. Experimental data indicates an important role of the innate immune system in cardiac remodeling and heart failure (HF. Complement is a central effector pathway of the innate immune system. Animals lacking parts of the complement system are protected from adverse remodeling. Based on these data, we hypothesized that peripheral complement levels could be a good marker for adverse remodeling and prognosis in patients with HF. Methods and Results. Since complement activation converges on the complement factor C3, we measured serum C3c, a stable C3-conversion product, in 197 patients with stable systolic HF. Subgroups with normal and elevated C3c levels were compared. C3c levels were elevated in 17% of the cohort. Patients with elevated C3c levels exhibited a trend to better survival, slightly higher LVEF, and lower NTpro-BNP values in comparison to patients with normal C3c values. No differences were found regarding NYHA functional class. Significantly more patients with elevated C3c had preexisting diabetes. The prevalence of CAD, arterial hypertension, and atrial fibrillation was not increased in patients with elevated C3c. Conclusion. Elevated C3c levels are associated with less adverse remodeling and improved survival in patients with stable systolic heart failure.

  20. Chaotic Feature in the Light Curve of 3C 273

    Institute of Scientific and Technical Information of China (English)

    Lei Liu

    2006-01-01

    Some nonlinear dynamical techniques, including state-space reconstruction and correlation integral, are used to analyze the light curve of 3C 273. The result is compared with a chaotic model. The similarities between them suggest there is a low-dimension chaotic attractor in the light curve of 3C 273.

  1. RFID Reader System Based on S3C64 1 0 and CR95HF%S3C6410和CR95HF的RFID读卡系统设计

    Institute of Scientific and Technical Information of China (English)

    刘占杰; 张艳; 赵阳

    2014-01-01

    For the lack of readers'weak performance,slow speed and poor portability,a design method of RFID reader system based on S3C6410 is proposed.Using S3C6410 microprocessor as a core,choosing CR95HF radio chip,a new kind of handled RFID reader is de-veloped which performs at high frequency and runs Android OS.The reader works at 13.56MHz HF frequency,supporting ISO 14443 and ISO 1 5 6 9 3 protocols.Experiment shows that the reader can read and write tags compiled with the protocols ,and the communication distance can meet the requirement.The reader has the features of portability,high stability and fast speed.%针对目前读卡器主频低、速度慢、便携性差等不足,提出了一种基于 S3 C6410的 RFID读卡系统设计方案。本文以高性能的S3C6410嵌入式微处理器为核心,选用新型的CR95HF射频芯片,开发设计了一款高主频的搭载Android嵌入式系统的新型手持式 RFID读卡器。该读卡器工作在高频13.56 MHz,支持 ISO14443、ISO15693等多种协议。实验证明,该读卡器能对符合协议的标签进行读写操作,读写距离能够满足需要,具有便携、稳定性高、处理速度快等特点。

  2. Control switching in high performance and fault tolerant control

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2010-01-01

    The problem of reliability in high performance control and in fault tolerant control is considered in this paper. A feedback controller architecture for high performance and fault tolerance is considered. The architecture is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization. By usi...

  3. Mechanical Properties of High Performance Cementitious Grout Masterflow 9300

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes tests carried out on the high performance grout MASTERFLOW 9300, developed by BASF Construction Chemicals A/S.......The present report describes tests carried out on the high performance grout MASTERFLOW 9300, developed by BASF Construction Chemicals A/S....

  4. Building Synergy: The Power of High Performance Work Systems.

    Science.gov (United States)

    Gephart, Martha A.; Van Buren, Mark E.

    1996-01-01

    Suggests that high-performance work systems create the synergy that lets companies gain and keep a competitive advantage. Identifies the components of high-performance work systems and critical action steps for implementation. Describes the results companies such as Xerox, Lever Brothers, and Corning Incorporated have achieved by using them. (JOW)

  5. A Theoretical Structure of High School Concert Band Performance

    Science.gov (United States)

    Bergee, Martin J.

    2015-01-01

    This study used exploratory (EFA) and confirmatory factor analysis (CFA) to verify a theoretical structure for high school concert band performance and to test that structure for viability, generality, and invariance. A total of 101 university students enrolled in two different bands rated two high school band performances (a "first"…

  6. The far-infrared emission of the radio-loud quasar 3C318

    CERN Document Server

    Podigachoski, P; Peletier, R F; Steendam, S

    2016-01-01

    3C318, a radio-loud quasar at z=1.574, is a subgalactic-sized radio source, and a good test-bed for the interplay between black hole and galaxy growth in the high-z Universe. Based on its IRAS, ISO, and SCUBA detections, it has long been considered as one of the most intrinsically luminous (L$_{\\mathrm{IR}}$ > 10$^{13}$ L$_{\\odot}$) infrared sources in the Universe. Recent far-infrared data from the Herschel Space Observatory reveal that most of the flux associated with 3C318 measured with earlier instruments in fact comes from a bright nearby source. Optical imaging and spectroscopy show that this infrared-bright source is a strongly star-forming pair of interacting galaxies at z=0.35. Adding existing Spitzer and SDSS photometry, we perform a spectral energy distribution analysis of the pair, and find that it has a combined infrared luminosity of L$_{\\mathrm{IR}}$ = 1.5 $\\times$ 10$^{12}$ L$_{\\odot}$, comparable to other intermediate-redshift ultra-luminous infrared galaxies studied with Herschel. Isolating ...

  7. Doping and stability of 3C-SiC: from thinfilm to bulk growth

    DEFF Research Database (Denmark)

    Jokubavicius, V.; Sun, J.; Linnarsson, M. K.

    Cubic silicon carbide (3C-SiC) could pave the way for development of advanced electronic and optoelectronic devices. It could be an excellent substrate for growth of nitride and epitaxial graphene layers. Boron doped 3C-SiC films could reach up to 60% efficiency and pave the way for a new solar...... cell technology. Nitrogen and boron doped 3C-SiC layers can depict a new infrared LED. Hexagonal SiC is an excellent substrate for heteropeitaxial growth of 3C-SiC due to excellent compatibility in lattice constant and thermal expansion coefficient. However, the growth of 3C-SiC on such substrates...... is still being followed by a number of obstacles like polytype stabilization and high density of double positioning boundaries in the grown material. The polytype stability during epitaxial growth of doped 3C-SiC has not been explored. Consequently, the polytype stability during bulk growth of doped 3C...

  8. Ti3C2 MXene co-catalyst on metal sulfide photo-absorbers for enhanced visible-light photocatalytic hydrogen production

    Science.gov (United States)

    Ran, Jingrun; Gao, Guoping; Li, Fa-Tang; Ma, Tian-Yi; Du, Aijun; Qiao, Shi-Zhang

    2017-01-01

    Scalable and sustainable solar hydrogen production through photocatalytic water splitting requires highly active and stable earth-abundant co-catalysts to replace expensive and rare platinum. Here we employ density functional theory calculations to direct atomic-level exploration, design and fabrication of a MXene material, Ti3C2 nanoparticles, as a highly efficient co-catalyst. Ti3C2 nanoparticles are rationally integrated with cadmium sulfide via a hydrothermal strategy to induce a super high visible-light photocatalytic hydrogen production activity of 14,342 μmol h-1 g-1 and an apparent quantum efficiency of 40.1% at 420 nm. This high performance arises from the favourable Fermi level position, electrical conductivity and hydrogen evolution capacity of Ti3C2 nanoparticles. Furthermore, Ti3C2 nanoparticles also serve as an efficient co-catalyst on ZnS or ZnxCd1-xS. This work demonstrates the potential of earth-abundant MXene family materials to construct numerous high performance and low-cost photocatalysts/photoelectrodes.

  9. High Performance Walls in Hot-Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, M.; Springer, D.; Dakin, B.; German, A.

    2015-01-01

    High performance walls represent a high priority measure for moving the next generation of new homes to the Zero Net Energy performance level. The primary goal in improving wall thermal performance revolves around increasing the wall framing from 2x4 to 2x6, adding more cavity and exterior rigid insulation, achieving insulation installation criteria meeting ENERGY STAR's thermal bypass checklist, and reducing the amount of wood penetrating the wall cavity.

  10. High performance pipelined multiplier with fast carry-save adder

    Science.gov (United States)

    Wu, Angus

    1990-01-01

    A high-performance pipelined multiplier is described. Its high performance results from the fast carry-save adder basic cell which has a simple structure and is suitable for the Gate Forest semi-custom environment. The carry-save adder computes the sum and carry within two gate delay. Results show that the proposed adder can operate at 200 MHz for a 2-micron CMOS process; better performance is expected in a Gate Forest realization.

  11. Microstructure and mechanical properties of thermal sprayed nanostructured Cr3C2-Ni20Cr coatings

    OpenAIRE

    Cecilio Alvares da Cunha; Nelson Batista de Lima; Jose Roberto Martinelli; Ana Helena de Almeida Bressiani; Armando Guilherme Fernando Padial; Lalgudi Venkataraman Ramanathan

    2008-01-01

    Cr3C2-Ni20Cr coatings have been used for corrosion and wear resistant applications. However, one of the shortcomings of these coatings is its low hardness, and consequent low wear resistance, for long term high temperature applications. Nanostructured coatings of many materials have exhibited higher hardness and strength compared with conventional coatings of the same material. Consequently, nanostructured coatings of other materials, including Cr3C2-Ni20Cr have been attempted to enhance over...

  12. A High Performance Track and Hold Circuit for High-Resolution High-Speed ADC

    Institute of Scientific and Technical Information of China (English)

    Hua Cai; Ping Li

    2011-01-01

    Design of a high performance track and hold (T/H) circuit for high-resolution high-speed analog-to-digital converter (ADC) is presented,which has been implemented in 0.18 μm CMOS process.An improved bootstrapped and bulk-switching technique is introduced to greatly minimize the nonlinearity of sampling network over a wide bandwidth,and the addition of a modified pre-charge circuit helps reducing the total power consumption.The experimental results show that the proposed T/H circuit achieves over 77 dB SFDR (spurious-free dynamic range) and 70 dB THD (total harmonic distortion) at 100 MHz sampling rate and maintains the performance with input frequency up to 305 MHz while consuming 47 mW power.

  13. Mapping the Conjugate Gradient Algorithm onto High Performance Heterogeneous Computers

    Science.gov (United States)

    2014-05-01

    HLL High Level Language HPC High-Performance Computing HPHC High-Performance Heterogeneous Computer I/O Input/Output IP Intellectual Property IPI...core manufacturing by automatically generating optimized floating-point IP cores within the FPGA itself. Such IPs have been successfully mapped onto...parallelism, which is perhaps the most important mapping consideration (Morris and Abed 2013). In 17 3 addition , portions of this thesis is referenced from

  14. Development of high performance vinyl acetate monomer (VAM) catalysts

    OpenAIRE

    2009-01-01

    The focus of this study was to develop high performance catalysts for the synthesis of vinyl acetate monomer (VAM). By systematic variation of different preparation parameters a multitude of shell catalysts consisting of PdAu nanoparticles supported on a bentonite carrier was explored. In order to investigate the influence of these alterations on catalytic performance, a catalyst classification was accomplished in a high-throughput Temkin test unit by comparison with a highly efficient commer...

  15. Fabrication and characterization of 3C-silicon carbide micro sensor for wireless blood pressure measurements

    Science.gov (United States)

    Basak, Nupur

    A potentially implantable single crystal 3C-SiC pressure sensor for blood pressure measurement was designed, simulated, fabricated, characterized and optimized. This research uses a single crystal 3C-SiC, for the first time, to demonstrate its application as a blood pressure measurement sensor. The sensor, which uses the epitaxial grown 3C-SiC membrane to measure changes in pressure, is designed to be wireless, biocompatible and linear. The SiC material was chosen for its superior physical, chemical and mechanical properties; the capacitive sensor uses a 3C-SiC membrane as one of the electrodes; and, the sensor system is wireless for comfort and to allow for convenient reading of real-time pressure data (wireless communication is enabled by connecting the sensor parallel to a planar inductor). Together, the variable capacitive sensor and planar inductor create a pressure sensitive resonant circuit. The sensor system described above allows for implantation into a human patient's body, after which the planar inductor can be coupled with an external inductor to receive data for real-time blood pressure measurement. Electroplating, thick photo-resist characterization, RIE etching, oxidation, CVD, chemical mechanical polishing and wafer bonding were optimized during the process of fabricating the sensor system and, in addition to detailing the sensor system simulation and characterization; the optimized processes are detailed in the dissertation. This absolute pressure sensor is designed to function optimally within the human blood pressure range of 50-350mmHg. The layout and modeling of the sensor uses finite element analysis (FEA) software. The simulations for membrane deflection, stress analysis and electro-mechanical analysis are performed for 100 μm2 and 400μm2sensors. The membrane deflection-pressure, capacitance-pressure and resonant frequency-pressure graphs were obtained, and detailed in the dissertation, along with the planar inductor simulation for

  16. Biglycan is a novel binding partner of fibroblast growth factor receptor 3c (FGFR3c) in the human testis

    DEFF Research Database (Denmark)

    Winge, S B; Nielsen, J; Jørgensen, Anders

    2015-01-01

    identified FGF1, FGF2, and FGF9 as the best candidates for natural ligands of FGFR3c in the testis. In addition, we screened non-FGF proteins and found that a proteoglycan biglycan (BGN) contains a sequence homologous to the FGFR3c binding site on FGF1, and is expressed in peritubular cells adjacent to FGFR3......-expressing spermatogonia. Experiments in a cell-free system confirmed that BGN binds to FGFR3c and FGF1. In conclusion, our findings further clarify the complex regulation of FGFR3c in the human testis. We postulate that BGN is a factor secreted by peritubular cells to modulate FGFR3c signaling and thus...

  17. Design method of water jet pump towards high cavitation performances

    Science.gov (United States)

    Cao, L. L.; Che, B. X.; Hu, L. J.; Wu, D. Z.

    2016-05-01

    As one of the crucial components for power supply, the propulsion system is of great significance to the advance speed, noise performances, stabilities and other associated critical performances of underwater vehicles. Developing towards much higher advance speed, the underwater vehicles make more critical demands on the performances of the propulsion system. Basically, the increased advance speed requires the significantly raised rotation speed of the propulsion system, which would result in the deteriorated cavitation performances and consequently limit the thrust and efficiency of the whole system. Compared with the traditional propeller, the water jet pump offers more favourite cavitation, propulsion efficiency and other associated performances. The present research focuses on the cavitation performances of the waterjet pump blade profile in expectation of enlarging its advantages in high-speed vehicle propulsion. Based on the specifications of a certain underwater vehicle, the design method of the waterjet blade with high cavitation performances was investigated in terms of numerical simulation.

  18. Characteristics of spent fuel, high-level waste, and other radioactive wastes which may require long-term isolation: Appendix 3A, ORIGEN2 decay tables for immobilized high-level waste, Appendix 3B, Interim high-level waste forms, Appendix 3C, User's guide to the high-level waste PC data base

    Energy Technology Data Exchange (ETDEWEB)

    1987-12-01

    The purpose of this report, and the information contained in the associated computerized data bases, is to establish the DOE/OCRWM reference characteristics of the radioactive waste materials that may be accepted by DOE for emplacement in he mined geologic disposal system. This report provides relevant technical data for use by DOE and its supporting contractors and is not intended to be a policy document. This document is backed up by five PC-compatible data bases, written in a user-oriented, menu-driven format, which were developed for this purpose. The data bases are the LWR Assemblies Data Base; the LWR Radiological Data Base; the LWR Quantities Data Base; the LWR NFA Hardware Data Base; and the High-Level Waste Data Base. The above data bases may be ordered using the included form. Volume 6 contains decay tables for immobilized high-level waste, information on interim high-level waste forms, and a user's guide to the high-level waste PC data base.

  19. High Performance Work System, HRD Climate and Organisational Performance: An Empirical Study

    Science.gov (United States)

    Muduli, Ashutosh

    2015-01-01

    Purpose: This paper aims to study the relationship between high-performance work system (HPWS) and organizational performance and to examine the role of human resource development (HRD) Climate in mediating the relationship between HPWS and the organizational performance in the context of the power sector of India. Design/methodology/approach: The…

  20. High School Employment, School Performance, and College Entry

    Science.gov (United States)

    Lee, Chanyoung; Orazem, Peter F.

    2010-01-01

    The proportion of U.S. high school students working during the school year ranges from 23% in the freshman year to 75% in the senior year. This study estimates how cumulative work histories during the high school years affect probability of dropout, high school academic performance, and the probability of attending college. Variations in…

  1. High performance current controller for particle accelerator magnets supply

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Bidoggia, Benoit; Munk-Nielsen, Stig;

    2013-01-01

    The electromagnets in modern particle accelerators require high performance power supply whose output is required to track the current reference with a very high accuracy (down to 50 ppm). This demands very high bandwidth controller design. A converter based on buck converter topology is used in ...

  2. Privacy Issues of the W3C Geolocation API

    CERN Document Server

    Doty, Nick; Wilde, Erik

    2010-01-01

    The W3C's Geolocation API may rapidly standardize the transmission of location information on the Web, but, in dealing with such sensitive information, it also raises serious privacy concerns. We analyze the manner and extent to which the current W3C Geolocation API provides mechanisms to support privacy. We propose a privacy framework for the consideration of location information and use it to evaluate the W3C Geolocation API, both the specification and its use in the wild, and recommend some modifications to the API as a result of our analysis.

  3. The Role of Performance Management in Creating and Maintaining a High-Performance Organization

    Directory of Open Access Journals (Sweden)

    André A. de Waal

    2015-04-01

    Full Text Available There is still a good deal of confusion in the literature about how the use of a performance management system affects overall organizational performance. Some researchers find that performance management enhances both the financial and non-financial results of an organization, while others do not find any positive effects or, at most, ambiguous effects. An important step toward getting more clarity in this relationship is to investigate the role performance management plays in creating and maintaining a high-performance organization (HPO. The purpose of this study is to integrate performance management analysis (PMA and high-performance organization (HPO. A questionnaire combining questions on PMA dimensions and HPO factors was administered to two European-based multinational firms. Based on 468 valid questionnaires, a correlation analysis was performed on the PMA dimensions and the HPO factors in order to test the impact of performance management on the factors of high organizational performance. The results show strong and significant correlations between all the PMA dimensions and all the HPO factors, indicating that a performance management system that fosters performance-driven behavior in the organization is of critical importance to strengthen overall financial and non-financial performance.

  4. High-Performance Management Practices and Employee Outcomes in Denmark

    DEFF Research Database (Denmark)

    Cristini, Annalisa; Eriksson, Tor; Pozzoli, Dario

    2013-01-01

    High-performance work practices are frequently considered to have positive effects on corporate performance, but what do they do for employees? After assessing the correlation between organizational innovation and firm performance, this article investigates whether high-involvement work practices...... affect workers in terms of wages, wage inequality and workforce composition. The analysis is based on a survey directed at Danish firms matched with linked employer–employee data and also examines whether the relationship between high-involvement work practices and employee outcomes is affected...

  5. High-Performance Management Practices and Employee Outcomes in Denmark

    DEFF Research Database (Denmark)

    Cristini, Annalisa; Eriksson, Tor; Pozzoli, Dario

    High-performance work practices are frequently considered to have positive effects on corporate performance, but what do they do for employees? After showing that organizational innovation is indeed positively associated with firm performance, we investigate whether high-involvement work practices...... are associ- ated with higher wages, changes in wage inequality and workforce composition, using data from a survey directed at Danish private sector firms matched with linked employer-employee data. We also examine whether the relationship be- tween high-involvement work practices and employee outcomes...

  6. Evaluation of GPFS Connectivity Over High-Performance Networks

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, Jay; Canon, Shane; Andrews, Matthew

    2009-02-17

    We present the results of an evaluation of new features of the latest release of IBM's GPFS filesystem (v3.2). We investigate different ways of connecting to a high-performance GPFS filesystem from a remote cluster using Infiniband (IB) and 10 Gigabit Ethernet. We also examine the performance of the GPFS filesystem with both serial and parallel I/O. Finally, we also present our recommendations for effective ways of utilizing high-bandwidth networks for high-performance I/O to parallel file systems.

  7. Spectroscopic monitoring of the Blazar 3C 454.3

    CERN Document Server

    Benítez, E; Raiteri, C M; Villata, M; Dultzin, D; Martínez, O; Perez-Camargo, B; Torrealba, J

    2009-01-01

    We performed an optical spectroscopic monitoring of the blazar 3C 454.3 from September 2003 to July 2008. Sixteen optical spectra were obtained during different runs, which constitute the first spectroscopic monitoring done in the rest-frame UV region (z=0.859). An overall flux variation of the MgII (2800 A) by a factor ~ 3 was observed, while the corresponding UV continuum (F_cont at 3000 A) changed by a factor ~ 14. The MgII emission lines respond proportionally to the continuum variations when the source is in a low-activity state. In contrast, near the optical outbursts detected in 2005 and 2007, the MgII emission lines showed little response to the continuum flux variations. During the monitored period the UV FeII flux changed by a factor ~ 6 and correlated with F_cont (r = 0.92). A negative correlation between EW(Mg II) and F_cont was found, i.e. the so-called "Intrinsic Baldwin Effect".

  8. Integral field spectroscopy of the radio galaxy 3C 171

    CERN Document Server

    Márquez, I; Durret, F; Petitjean, P

    2000-01-01

    We have performed integral field spectroscopy of the radio galaxy 3C 171 (redshift z=0.238) with the TIGER instrument at the Canada France Hawaii telescope in the Hbeta-[OIII]4959-5007 wavelength region. We present the reconstructed Hbeta and [OIII] images and compare them to the HST and radio maps. We discuss the variations of the [OIII]/Hbeta line ratio throughout the nebulosity. We also analyze the velocity field in detail, in particular the presence of several components. We find that the kinematics derived with emission lines in the central region (inside 1 arcsec) are compatible with a disk-like rotation of low amplitude (50 km/s). The continuum surface brightness profile follows an r^{1/4} law, suggesting that the underlying galaxy is an elliptical with an effective radius of 15 kpc. We have fit two components in the region centered 2.7 arcsec to the West and of extension 3 arcsec^2. We find that the blueshifted component is an extension of the central part, whereas the second one is redshifted by 600 ...

  9. Doped Polycrystalline 3C-SiC Films Deposited by LPCVD for Radio-Frequency MEMS Applications

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yong-Mei; SUN Guo-Sheng; NING Jin; LIU Xing-Fang; ZHAO Wan-Shun; WANG Lei; LI Jin-Min

    2008-01-01

    Polycrystalline 3C-SiC films are deposited on SiO2 coated Si substrates by low pressure chemical vapour deposition (LPCVD) with C3H8 and SiH4 as precursors. Controlled nitrogen doping is performed by adding NH3 during SiC growth to obtain the low resistivity 3C-SiC films. X-ray diffraction (XRD) patterns indicate that the deposited films are highly textured (111) orientation. The surface morphology and roughness are determined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The surface features are spherulitic texture with average grain size of 100nm, and the rms roughness is 20nm (AFM 5 × 5μm images). Polycrysta/line 3C-SiC films with highly orientational texture and good surface morphology deposited on SiO2 coated Si substrates could be used to fabricate rf microelectromechanical systems (MEMS) devices such as SiC based filters.

  10. Progress and Challenges in High Performance Computer Technology

    Institute of Scientific and Technical Information of China (English)

    Xue-Jun Yang; Yong Dou; Qing-Feng Hu

    2006-01-01

    High performance computers provide strategic computing power in the construction of national economy and defense, and become one of symbols of the country's overall strength. Over 30 years, with the supports of governments, the technology of high performance computers is in the process of rapid development, during which the computing performance increases nearly 3 million times and the processors number expands over 10 hundred thousands times. To solve the critical issues related with parallel efficiency and scalability, scientific researchers pursued extensive theoretical studies and technical innovations. The paper briefly looks back the course of building high performance computer systems both at home and abroad,and summarizes the significant breakthroughs of international high performance computer technology. We also overview the technology progress of China in the area of parallel computer architecture, parallel operating system and resource management,parallel compiler and performance optimization, environment for parallel programming and network computing. Finally, we examine the challenging issues, "memory wall", system scalability and "power wall", and discuss the issues of high productivity computers, which is the trend in building next generation high performance computers.

  11. Molecular Gas in the Powerful Radio Galaxies 3C~31 and 3C~264 Major or Minor Mergers?

    CERN Document Server

    Lim, J; Combes, F

    2000-01-01

    We report the detection of $^{12}$CO~($1 \\to 0$) and $^{12}$CO~($2 \\to 1$) emission from the central regions ($\\lesssim 5$--$10 {\\rm kpc}$) of the two powerful radio galaxies 3C~31 and 3C~264. Their individual CO emission exhibits a double-horned line profile that is characteristic of an inclined rotating disk with a central depression at the rising part of its rotation curve. The inferred disk or ring distributions of the molecular gas is consistent with the observed presence of dust disks or rings detected optically in the cores of both galaxies. For a CO to H$_2$ conversion factor similar to that of our Galaxy, the corresponding total mass in molecular hydrogen gas is $(1.3 \\pm 0.2) \\times 10^9 {\\rm M_{\\odot}}$ in 3C~31 and $(0.31 \\pm 0.06) \\times 10^9 {\\rm M_{\\odot}}$ in 3C~264. Despite their relatively large molecular-gas masses and other peculiarities, both 3C~31 and 3C~264, as well as many other powerful radio galaxies in the (revised) 3C catalog, are known to lie within the fundamental plane of normal...

  12. High Performance Low Mass Nanowire Enabled Heatpipe Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Illuminex Corporation proposes a NASA Phase I SBIR project to develop high performance, lightweight, low-profile heat pipes with enhanced thermal transfer properties...

  13. Energy Design Guidelines for High Performance Schools: Tropical Island Climates

    Energy Technology Data Exchange (ETDEWEB)

    None

    2004-11-01

    Design guidelines outline high performance principles for the new or retrofit design of K-12 schools in tropical island climates. By incorporating energy improvements into construction or renovation plans, schools can reduce energy consumption and costs.

  14. Affordable High Performance Electromagnetically Clean Solar Arrays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an Electromagnetically Clean Solar Array (ECSA) with enhanced performance, in Watts/kg and Watts/m2, using flight proven, high efficiency solar cells. For...

  15. DEVELOPING A NEW GENERATION OF HIGH PERFORMANCE COMPOSITE CEMENT

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper proposed a new generation of high performance composite cement which is designed according to the optimization of composition and structure of cement paste and is manufactured by blending the different components with special composite techniques. Each of these components has its different special property, and should be compatible with each other and match each other, and the properties of them are complementary mutually. At present, such kind of high performance composite cement can be manufactured with high reactivity cement clinker, ground granulated blast-furnace slag, high grade fly ash, silica fume etc.

  16. A DRAM compiler algorithm for high performance VLSI embedded memories

    Science.gov (United States)

    Eldin, A. G.

    1992-01-01

    In many applications, the limited density of the embedded SRAM does not allow integrating the memory on the same chip with other logic and functional blocks. In such cases, the embedded DRAM provides the optimum combination of very high density, low power, and high performance. For ASIC's to take full advantage of this design strategy, an efficient and highly reliable DRAM compiler must be used. The embedded DRAM architecture, cell, and peripheral circuit design considerations and the algorithm of a high performance memory compiler are presented .

  17. Optical Periodicity Analysis of 3C 446 using Period04

    Indian Academy of Sciences (India)

    Fei Guo; Hao Jing Zhang

    2014-09-01

    All the data of the blazar 3C446 at 8, 4.8, 14 and 22 GHz, presented in publications from 1977 to 2006, have been compiled to generate light curves. The light curves show violent activity of 3C446. Using Period04 analysis method, we have found that there is a period of 7.2 yr, which is consistent with the results that we found using wavelet analysis method. We get the instability region as = 123.83.

  18. Accelerating R with high performance linear algebra libraries

    Directory of Open Access Journals (Sweden)

    Bogdan Oancea

    2015-09-01

    Full Text Available Linear algebra routines are basic building blocks for the statistical software. In this paper we analyzed how can we improve R performance for matrix computations. We benchmarked few matrix operations using the standard linear algebra libraries included in the R distribution and high performance libraries like OpenBLAS, GotoBLAS and MKL. Our tests showed the best results are obtained with the MKL library, the other two libraries having similar performances, but lower than MKL.

  19. Understanding Structure-Function Relationship in Hybrid Co3O4-Fe2O3/C Lithium-Ion Battery Electrodes.

    Science.gov (United States)

    Sultana, Irin; Rahman, Md Mokhlesur; Ramireddy, Thrinathreddy; Sharma, Neeraj; Poddar, Debasis; Khalid, Abbas; Zhang, Hongzhou; Chen, Ying; Glushenkov, Alexey M

    2015-09-23

    A range of high-capacity Li-ion anode materials (conversion reactions with lithium) suffer from poor cycling stability and limited high-rate performance. These issues can be addressed through hybridization of multiple nanostructured components in an electrode. Using a Co3O4-Fe2O3/C system as an example, we demonstrate that the cycling stability and rate performance are improved in a hybrid electrode. The hybrid Co3O4-Fe2O3/C electrode exhibits long-term cycling stability (300 cycles) at a moderate current rate with a retained capacity of approximately 700 mAh g(-1). The reversible capacity of the Co3O4-Fe2O3/C electrode is still about 400 mAh g(-1) (above the theoretical capacity of graphite) at a high current rate of ca. 3 A g(-1), whereas Co3O4-Fe2O3, Fe2O3/C, and Co3O4/C electrodes (used as controls) are unable to operate as effectively under identical testing conditions. To understand the structure-function relationship in the hybrid electrode and the reasons for the enhanced cycling stability, we employed a combination of ex situ and in situ techniques. Our results indicate that the improvements in the hybrid electrode originate from the combination of sequential electrochemical activity of the transition metal oxides with an enhanced electronic conductivity provided by percolating carbon chains.

  20. Variational formulation of high performance finite elements: Parametrized variational principles

    Science.gov (United States)

    Felippa, Carlos A.; Militello, Carmello

    1991-01-01

    High performance elements are simple finite elements constructed to deliver engineering accuracy with coarse arbitrary grids. This is part of a series on the variational basis of high-performance elements, with emphasis on those constructed with the free formulation (FF) and assumed natural strain (ANS) methods. Parametrized variational principles that provide a foundation for the FF and ANS methods, as well as for a combination of both are presented.

  1. Optical Thermal Characterization Enables High-Performance Electronics Applications

    Energy Technology Data Exchange (ETDEWEB)

    2016-02-01

    NREL developed a modeling and experimental strategy to characterize thermal performance of materials. The technique provides critical data on thermal properties with relevance for electronics packaging applications. Thermal contact resistance and bulk thermal conductivity were characterized for new high-performance materials such as thermoplastics, boron-nitride nanosheets, copper nanowires, and atomically bonded layers. The technique is an important tool for developing designs and materials that enable power electronics packaging with small footprint, high power density, and low cost for numerous applications.

  2. Systematic Design of High-performance Hybrid Feedback Algorithms

    Science.gov (United States)

    2015-06-24

    AFRL-AFOSR-VA-TR-2015-0280 Systematic design of high-performance hybrid feedback algorithms Andrew Teel UNIVERSITY OF CALIFORNIA SANTA BARBARA Final...ADDRESS(ES) Andrew R. Teel Department of Electrical and Computer Engineering University of California Santa Barbara, CA 93106-9560 8. PERFORMING...interest to the Air Force because of the high degree of autonomy and cooperation that future reconnaissance and fighter aircraft will maintain. Complex

  3. Teacher Performance Trajectories in High- and Lower-Poverty Schools

    Science.gov (United States)

    Xu, Zeyu; Özek, Umut; Hansen, Michael

    2015-01-01

    This study explores whether teacher performance trajectory over time differs by school-poverty settings. Focusing on elementary school mathematics teachers in North Carolina and Florida, we find no systematic relationship between school student poverty rates and teacher performance trajectories. In both high- (=60% free/reduced-price lunch [FRPL])…

  4. Contemporary high performance computing from petascale toward exascale

    CERN Document Server

    Vetter, Jeffrey S

    2015-01-01

    A continuation of Contemporary High Performance Computing: From Petascale toward Exascale, this second volume continues the discussion of HPC flagship systems, major application workloads, facilities, and sponsors. The book includes of figures and pictures that capture the state of existing systems: pictures of buildings, systems in production, floorplans, and many block diagrams and charts to illustrate system design and performance.

  5. Manufacturing Advantage: Why High-Performance Work Systems Pay Off.

    Science.gov (United States)

    Appelbaum, Eileen; Bailey, Thomas; Berg, Peter; Kalleberg, Arne L.

    A study examined the relationship between high-performance workplace practices and the performance of plants in the following manufacturing industries: steel, apparel, and medical electronic instruments and imaging. The multilevel research methodology combined the following data collection activities: (1) site visits; (2) collection of plant…

  6. Two Profiles of the Dutch High Performing Employee

    Science.gov (United States)

    de Waal, A. A.; Oudshoorn, Michella

    2015-01-01

    Purpose: The purpose of this study is to explore the profile of an ideal employee, to be more precise the behavioral characteristics of the Dutch high-performing employee (HPE). Organizational performance depends for a large part on the commitment of employees. Employees provide their knowledge, skills, experiences and creativity to the…

  7. High-Performance Java Codes for Computational Fluid Dynamics

    Science.gov (United States)

    Riley, Christopher; Chatterjee, Siddhartha; Biswas, Rupak; Biegel, Bryan (Technical Monitor)

    2001-01-01

    The computational science community is reluctant to write large-scale computationally -intensive applications in Java due to concerns over Java's poor performance, despite the claimed software engineering advantages of its object-oriented features. Naive Java implementations of numerical algorithms can perform poorly compared to corresponding Fortran or C implementations. To achieve high performance, Java applications must be designed with good performance as a primary goal. This paper presents the object-oriented design and implementation of two real-world applications from the field of Computational Fluid Dynamics (CFD): a finite-volume fluid flow solver (LAURA, from NASA Langley Research Center), and an unstructured mesh adaptation algorithm (2D_TAG, from NASA Ames Research Center). This work builds on our previous experience with the design of high-performance numerical libraries in Java. We examine the performance of the applications using the currently available Java infrastructure and show that the Java version of the flow solver LAURA performs almost within a factor of 2 of the original procedural version. Our Java version of the mesh adaptation algorithm 2D_TAG performs within a factor of 1.5 of its original procedural version on certain platforms. Our results demonstrate that object-oriented software design principles are not necessarily inimical to high performance.

  8. Hybrids of Two-Dimensional Ti3C2 and TiO2 Exposing {001} Facets toward Enhanced Photocatalytic Activity.

    Science.gov (United States)

    Peng, Chao; Yang, Xianfeng; Li, Yuhang; Yu, Hao; Wang, Hongjuan; Peng, Feng

    2016-03-09

    Effectively harvesting light to generate long-lived charge carriers to suppress the recombination of electrons and holes is crucial for photocatalytic reactions. Exposing the highly active facets has been regarded as a powerful approach to high-performance photocatalysts. Herein, a hybrid comprised of {001} facets of TiO2 nanosheets and layered Ti3C2, an emerging 2D material, was synthesized by a facile hydrothermal partial oxidation of Ti3C2. The in situ growth of TiO2 nanosheets on Ti3C2 allows for the interface with minimized defects, which was demonstrated by high-resolution transmission electron microscopy and density functional theory calculations. The highly active {001} facets of TiO2 afford high-efficiency photogeneration of electron-hole pairs, meanwhile the carrier separation is substantially promoted by the hole trapping effect by the interfacial Schottky junction with 2D Ti3C2 acting as a reservoir of holes. The improved charge separation and exposed active facets dramatically boost the photocatalytic degradation of methyl orange dye, showing the promise of 2D transition metal carbide for fabricating functional catalytic materials.

  9. 3C 273 with NuSTAR: Unveiling the AGN

    CERN Document Server

    Madsen, Kristin K; Walton, Dominic J; Harrison, Fiona A; Ballantyne, David R; Boggs, Steve E; Brenneman, Laura W; Christensen, Finn E; Craig, William W; Fabian, Andrew C; Forster, Karl; Grefenstette, Brian W; Guainazzi, Matteo; Hailey, Charles J; Madejski, Greg M; Matt, Giorgio; Stern, Daniel; Zhang, William W

    2015-01-01

    We present results from a 244 ks $NuSTAR$ observation of 3C 273, obtained during a cross-calibration campaign with the $Chandra$, $INTEGRAL$, $Suzaku$, $Swift$, and $XMM-Newton$ observatories. We show that the spectrum, when fit with a power-law model using data from all observatories except $INTEGRAL$ over the 1-78 keV band, leaves significant residuals in the $NuSTAR$ data between 30-78 keV. The $NuSTAR$ 3-78 keV spectrum is well-described by an exponentially cutoff power-law ($\\Gamma = 1.646 \\pm 0.006$, E$_\\mathrm{cutoff} = 202_{-34}^{+51}$ keV) with a weak reflection component from cold, dense material. There is also evidence for a weak ($EW = 23 \\pm 11$ eV) neutral iron line. We interpret these features as arising from coronal emission plus reflection off an accretion disk or distant material. Beyond 80 keV $INTEGRAL$ data show clear excess flux relative to an extrapolation of the AGN model fit to $NuSTAR$. This high-energy power-law is consistent with the presence of a beamed jet, which begins to domina...

  10. Target cell APOBEC3C can induce limited G-to-A mutation in HIV-1.

    Directory of Open Access Journals (Sweden)

    Khaoula Bourara

    2007-10-01

    Full Text Available The evolutionary success of primate lentiviruses reflects their high capacity to mutate and adapt to new host species, immune responses within individual hosts, and, in recent years, antiviral drugs. APOBEC3G (A3G and APOBEC3F (A3F are host cell DNA-editing enzymes that induce extensive HIV-1 mutation that severely attenuates viral replication. The HIV-1 virion infectivity factor (Vif, expressed in vivo, counteracts the antiviral activity of A3G and A3F by inducing their degradation. Other APOBECs may contribute more to viral diversity by inducing less extensive mutations allowing viral replication to persist. Here we show that in APOBEC3C (A3C-expressing cells infected with the patient-derived HIV-1 molecular clones 210WW, 210WM, 210MW, and 210MM, and the lab-adapted molecular clone LAI, viral G-to-A mutations were detected in the presence of Vif expression. Mutations occurred primarily in the GA context and were relatively infrequent, thereby allowing for spreading infection. The mutations were absent in cells lacking A3C but were induced after transient expression of A3C in the infected target cell. Inhibiting endogenous A3C by RNA interference in Magi cells prevented the viral mutations. Thus, A3C is necessary and sufficient for G-to-A mutations in some HIV-1 strains. A3C-induced mutations occur at levels that allow replication to persist and may therefore contribute to viral diversity. Developing drugs that inhibit A3C may be a novel strategy for delaying viral escape from immune or antiretroviral inhibition.

  11. Target Cell APOBEC3C Can Induce Limited G-to-A Mutation in HIV-1

    Science.gov (United States)

    Bourara, Khaoula; Liegler, Teri J; Grant, Robert M

    2007-01-01

    The evolutionary success of primate lentiviruses reflects their high capacity to mutate and adapt to new host species, immune responses within individual hosts, and, in recent years, antiviral drugs. APOBEC3G (A3G) and APOBEC3F (A3F) are host cell DNA-editing enzymes that induce extensive HIV-1 mutation that severely attenuates viral replication. The HIV-1 virion infectivity factor (Vif), expressed in vivo, counteracts the antiviral activity of A3G and A3F by inducing their degradation. Other APOBECs may contribute more to viral diversity by inducing less extensive mutations allowing viral replication to persist. Here we show that in APOBEC3C (A3C)-expressing cells infected with the patient-derived HIV-1 molecular clones 210WW, 210WM, 210MW, and 210MM, and the lab-adapted molecular clone LAI, viral G-to-A mutations were detected in the presence of Vif expression. Mutations occurred primarily in the GA context and were relatively infrequent, thereby allowing for spreading infection. The mutations were absent in cells lacking A3C but were induced after transient expression of A3C in the infected target cell. Inhibiting endogenous A3C by RNA interference in Magi cells prevented the viral mutations. Thus, A3C is necessary and sufficient for G-to-A mutations in some HIV-1 strains. A3C-induced mutations occur at levels that allow replication to persist and may therefore contribute to viral diversity. Developing drugs that inhibit A3C may be a novel strategy for delaying viral escape from immune or antiretroviral inhibition. PMID:17967058

  12. CRPC research into linear algebra software for high performance computers

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J.; Walker, D.W. [Oak Ridge National Lab., TN (United States). Mathematical Sciences Section; Dongarra, J.J. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Computer Science]|[Oak Ridge National Lab., TN (United States). Mathematical Sciences Section; Pozo, R. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Computer Science; Sorensen, D.C. [Rice Univ., Houston, TX (United States). Dept. of Computational and Applied Mathematics

    1994-12-31

    In this paper the authors look at a number of approaches being investigated in the Center for Research on Parallel Computation (CRPC) to develop linear algebra software for high-performance computers. These approaches are exemplified by the LAPACK, templates, and ARPACK projects. LAPACK is a software library for performing dense and banded linear algebra computations, and was designed to run efficiently on high-performance computers. The authors focus on the design of the distributed-memory version of LAPACK, and on an object-oriented interface to LAPACK.

  13. Contemporary high performance computing from petascale toward exascale

    CERN Document Server

    Vetter, Jeffrey S

    2013-01-01

    Contemporary High Performance Computing: From Petascale toward Exascale focuses on the ecosystems surrounding the world's leading centers for high performance computing (HPC). It covers many of the important factors involved in each ecosystem: computer architectures, software, applications, facilities, and sponsors. The first part of the book examines significant trends in HPC systems, including computer architectures, applications, performance, and software. It discusses the growth from terascale to petascale computing and the influence of the TOP500 and Green500 lists. The second part of the

  14. High-Performance Matrix-Vector Multiplication on the GPU

    DEFF Research Database (Denmark)

    Sørensen, Hans Henrik Brandenborg

    2012-01-01

    In this paper, we develop a high-performance GPU kernel for one of the most popular dense linear algebra operations, the matrix-vector multiplication. The target hardware is the most recent Nvidia Tesla 20-series (Fermi architecture), which is designed from the ground up for scientific computing....... We show that it is essentially a matter of fully utilizing the fine-grained parallelism of the many-core GPU in order to achieve high-performance for dense matrix-vector multiplication. We show that auto-tuning can be successfully employed to the GPU kernel so that it performs well for all matrix...

  15. Driver Design of Touch Screen Based on S3C2410 Embedded System%基于S3C2410嵌入式系统的触摸屏驱动设计

    Institute of Scientific and Technical Information of China (English)

    冯先成; 李小鹏; 司擎华

    2012-01-01

    In order to meet the requirements of the good performance, stable operation, high precision for touch screen in the embedded system, a kind of driver design of touch screen in embedded system is put forward. The scheme is based on the S3C2q10 microprocessor with touch screen hardware interface in embedded ucos operating system software implementation, using external transistor connected with the touch screen to the S3C2410 interface circuit. The designed driver can read out the voltage value of X-Y coordinates and control the touch-screen by using S3C2410's waiting interrupt mode and automatic X-Y coordinate conversion mode. The touch state detection and touch data conversion are completed efficiently. The realiza- tion method is simple and efficient, and is easily to be implemented.%为满足性能良好、运行稳定、精度高的触摸屏在嵌入式系统中的广泛应用,提出了一种嵌入式系统的触摸屏驱动设计,这种方案基于S3C2410微处理器与触摸屏的硬件接口在嵌入式UCOS操作系统中的软件驱动实现,采用外部晶体管连接触摸屏到S3C2410的接口电路,并利用S3C2410的等待中断模式和自动X-Y坐标转换工作模式,读出与X-Y坐标有关的电压值。高效地完成了触摸状态的检测以及触摸数据的转换,其实现方法具有简便高效,易于实现等特点。

  16. RAID-M: A high performance RAID Matrix mass storage

    Institute of Scientific and Technical Information of China (English)

    LIU Peng; LI Sanli; Francis C.M.Lau; SHI Yao; HUANG Feng

    2005-01-01

    In the light of the increasingly serious I/O bottleneck problem, the paper puts forward a method named RAID-M (RAID Matrix) to build high performance mass storage from cheap PC components based on the idea of multi-channel I/O and parallel access.Theoretical analyses prove that different RAID-M configurations vary their performance,space utilization and reliability, meeting various application goals. Experiments show that both the sequential read performance and sequential write performance of a RAID-M prototype machine have broken through the limitation of 32 bit/33 MHz PCI bus.

  17. Performance measurement and modeling of component applications in a high performance computing environment : a case study.

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Robert C.; Ray, Jaideep; Malony, A. (University of Oregon, Eugene, OR); Shende, Sameer (University of Oregon, Eugene, OR); Trebon, Nicholas D.

    2003-11-01

    We present a case study of performance measurement and modeling of a CCA (Common Component Architecture) component-based application in a high performance computing environment. We explore issues peculiar to component-based HPC applications and propose a performance measurement infrastructure for HPC based loosely on recent work done for Grid environments. A prototypical implementation of the infrastructure is used to collect data for a three components in a scientific application and construct performance models for two of them. Both computational and message-passing performance are addressed.

  18. A Component Architecture for High-Performance Scientific Computing

    Energy Technology Data Exchange (ETDEWEB)

    Bernholdt, David E; Allan, Benjamin A; Armstrong, Robert C; Bertrand, Felipe; Chiu, Kenneth; Dahlgren, Tamara L; Damevski, Kostadin; Elwasif, Wael R; Epperly, Thomas G; Govindaraju, Madhusudhan; Katz, Daniel S; Kohl, James A; Krishnan, Manoj Kumar; Kumfert, Gary K; Larson, J Walter; Lefantzi, Sophia; Lewis, Michael J; Malony, Allen D; McInnes, Lois C; Nieplocha, Jarek; Norris, Boyana; Parker, Steven G; Ray, Jaideep; Shende, Sameer; Windus, Theresa L; Zhou, Shujia

    2006-07-03

    The Common Component Architecture (CCA) provides a means for software developers to manage the complexity of large-scale scientific simulations and to move toward a plug-and-play environment for high-performance computing. In the scientific computing context, component models also promote collaboration using independently developed software, thereby allowing particular individuals or groups to focus on the aspects of greatest interest to them. The CCA supports parallel and distributed computing as well as local high-performance connections between components in a language-independent manner. The design places minimal requirements on components and thus facilitates the integration of existing code into the CCA environment. The CCA model imposes minimal overhead to minimize the impact on application performance. The focus on high performance distinguishes the CCA from most other component models. The CCA is being applied within an increasing range of disciplines, including combustion research, global climate simulation, and computational chemistry.

  19. A Component Architecture for High-Performance Scientific Computing

    Energy Technology Data Exchange (ETDEWEB)

    Bernholdt, D E; Allan, B A; Armstrong, R; Bertrand, F; Chiu, K; Dahlgren, T L; Damevski, K; Elwasif, W R; Epperly, T W; Govindaraju, M; Katz, D S; Kohl, J A; Krishnan, M; Kumfert, G; Larson, J W; Lefantzi, S; Lewis, M J; Malony, A D; McInnes, L C; Nieplocha, J; Norris, B; Parker, S G; Ray, J; Shende, S; Windus, T L; Zhou, S

    2004-12-14

    The Common Component Architecture (CCA) provides a means for software developers to manage the complexity of large-scale scientific simulations and to move toward a plug-and-play environment for high-performance computing. In the scientific computing context, component models also promote collaboration using independently developed software, thereby allowing particular individuals or groups to focus on the aspects of greatest interest to them. The CCA supports parallel and distributed computing as well as local high-performance connections between components in a language-independent manner. The design places minimal requirements on components and thus facilitates the integration of existing code into the CCA environment. The CCA model imposes minimal overhead to minimize the impact on application performance. The focus on high performance distinguishes the CCA from most other component models. The CCA is being applied within an increasing range of disciplines, including combustion research, global climate simulation, and computational chemistry.

  20. WOMBAT: A Scalable and High-performance Astrophysical Magnetohydrodynamics Code

    Science.gov (United States)

    Mendygral, P. J.; Radcliffe, N.; Kandalla, K.; Porter, D.; O’Neill, B. J.; Nolting, C.; Edmon, P.; Donnert, J. M. F.; Jones, T. W.

    2017-02-01

    We present a new code for astrophysical magnetohydrodynamics specifically designed and optimized for high performance and scaling on modern and future supercomputers. We describe a novel hybrid OpenMP/MPI programming model that emerged from a collaboration between Cray, Inc. and the University of Minnesota. This design utilizes MPI-RMA optimized for thread scaling, which allows the code to run extremely efficiently at very high thread counts ideal for the latest generation of multi-core and many-core architectures. Such performance characteristics are needed in the era of “exascale” computing. We describe and demonstrate our high-performance design in detail with the intent that it may be used as a model for other, future astrophysical codes intended for applications demanding exceptional performance.

  1. High Performance Computing in Science and Engineering '14

    CERN Document Server

    Kröner, Dietmar; Resch, Michael

    2015-01-01

    This book presents the state-of-the-art in supercomputer simulation. It includes the latest findings from leading researchers using systems from the High Performance Computing Center Stuttgart (HLRS). The reports cover all fields of computational science and engineering ranging from CFD to computational physics and from chemistry to computer science with a special emphasis on industrially relevant applications. Presenting findings of one of Europe’s leading systems, this volume covers a wide variety of applications that deliver a high level of sustained performance. The book covers the main methods in high-performance computing. Its outstanding results in achieving the best performance for production codes are of particular interest for both scientists and   engineers. The book comes with a wealth of color illustrations and tables of results.  

  2. Performance characterization of solid oxide cells under high pressure

    DEFF Research Database (Denmark)

    Sun, Xiufu; Bonaccorso, Alfredo Damiano; Graves, Christopher R.;

    2014-01-01

    Solid oxide electrolysis cells (SOECs) offer a great potential for large scale conversion of renewable electrical energy into chemical energy via electrolysis of H2O and CO2 to produce syngas (H2 + CO). The produced syngas can be further catalytically converted into various gaseous or liquid...... hydrocarbon fuels, which is normally performed at high pressure to achieve a high yield. Operation of SOECs at elevated pressure will therefore facilitate integration with the downstream fuel synthesis and is furthermore advantageous as it increases the cell performance. In this work, recent pressurised test...... results of a planar Ni-YSZ (YSZ: Yttria stabilized Zirconia) supported solid oxide cell are presented. The test was performed at 800 °C at pressures up to 15 bar. A comparison of the electrochemical performance of the cell at 1 and 3 bar shows a significant and equal performance gain at higher pressure...

  3. Design and Modeling of High Performance Permanent Magnet Synchronous Machines

    NARCIS (Netherlands)

    Van der Geest, M.

    2015-01-01

    The electrification of transportation, and especially aerospace transportation, increases the demand for high performance electrical machines. Those machines often need to be fault-tolerant, cheap, highly efficient, light and small, and interface well with the inverter. In addition, the development

  4. Ideation High Performers: A Study of Motivational Factors

    Science.gov (United States)

    Bergendahl, Magnus; Magnusson, Mats; Björk, Jennie

    2015-01-01

    As innovation today is one of the keys to success for firms, creativity among employees becomes an important asset and the understanding about what motivates employees in ideation is consequently of high interest. This article addresses differences in motivation among high and low performers in ideation and contributes to existing theory by…

  5. High performance installation for drill and blast advance Mitholz, Switzerland

    Institute of Scientific and Technical Information of China (English)

    Jost Wenk

    2004-01-01

    The section Mitholz of the L tschberg Alp - Transit tunnel consists basically of 3 drill & blast advances with a cross section of 63 - 69m2 and a total length of 25 km.The high - performance back - up installation in use distinguishes itself by the following substantial innovations:The joint venture SATCO ( STRABAG AG, Rothpletz, Lienhard & Cie. , Walo Bertschinger AG, Vinci Construction,Skanska Europe AB), the c ontractor in charge, is achieving very high rates of advance, thanks to the high - performance back - up installations.- The chosen heading system has a positive effect on the entire construction program. Supplementary work can be done within the planned time schedule - Owing to the excellent performance, the joint venture SATCO is ahead on the construction program by about 700m.- The high rates of advance result for the customer in a positive return on investment - The installed equipment results in a higher safety at the workplace for the workers

  6. High Performance Fiber Reinforced Cement Composites 6 HPFRCC 6

    CERN Document Server

    Reinhardt, Hans; Naaman, A

    2012-01-01

    High Performance Fiber Reinforced Cement Composites (HPFRCC) represent a class of cement composites whose stress-strain response in tension undergoes strain hardening behaviour accompanied by multiple cracking, leading to a high strain prior to failure. The primary objective of this International Workshop was to provide a compendium of up-to-date information on the most recent developments and research advances in the field of High Performance Fiber Reinforced Cement Composites. Approximately 65 contributions from leading world experts are assembled in these proceedings and provide an authoritative perspective on the subject. Special topics include fresh and hardening state properties; self-compacting mixtures; mechanical behavior under compressive, tensile, and shear loading; structural applications; impact, earthquake and fire resistance; durability issues; ultra-high performance fiber reinforced concrete; and textile reinforced concrete. Target readers: graduate students, researchers, fiber producers, desi...

  7. Inorganic nanostructured materials for high performance electrochemical supercapacitors.

    Science.gov (United States)

    Liu, Sheng; Sun, Shouheng; You, Xiao-Zeng

    2014-02-21

    Electrochemical supercapacitors (ES) are a well-known energy storage system that has high power density, long life-cycle and fast charge-discharge kinetics. Nanostructured materials are a new generation of electrode materials with large surface area and short transport/diffusion path for ions and electrons to achieve high specific capacitance in ES. This mini review highlights recent developments of inorganic nanostructure materials, including carbon nanomaterials, metal oxide nanoparticles, and metal oxide nanowires/nanotubes, for high performance ES applications.

  8. Multiwavelength Observations of 3C66A in 2003

    Science.gov (United States)

    Boettcher, M.; Joshi, M.; Fossati, G.; Smith, I. A.; Mukherjee, R.; Bramel, D.; Cui, W.; WEBT Collaboration

    2004-08-01

    The radio-selected BL Lac object 3C66A was the target of an intensive multiwavelength observing campaign in the last quarter of 2003 and early 2004. It was monitored by the Whole Earth Blazar Telescope (WEBT) collaboration of optical observers, in tandem with 20 X-ray monitoring observations by the Rossi X-Ray Timing Explorer (RXTE), VHE gamma-ray observations by STACEE and VERITAS, and long-term monitoring at radio frequencies. In addition, 9 high-spatial-resolution observations using the VLA are being carried out during the campaign and throughout the year 2004 to follow possible structural changes of the source. A gradual brightening of the source over the course of the campaign was observed at all optical frequencies, culminating in a very bright flare at the end of January 2004. Optical light curves indicate intraday microvariability on time scales down to about 1.3 hours. No significant color-magnitude correlation for the entire data set was evident, but there is a slight indication of a hardness - intensity anti-correlation on intraday time scales. The X-ray spectrum is consistent with a power-law with a photon spectral index of ˜ 2.1, indicating that the RXTE energy band might be located right at the intersection of the synchrotron and the high-energy emission components of the broadband spectral energy distribution. No significant flux or spectral variability at X-ray energies was detected. We extracted snapshot spectral energy distributions at various times throughout the campaign, and present first spectral fits to those SEDs. This work was partially supported by NASA RXTE GO grant no. NNG 04GB13G.

  9. High-performance work systems and workplace performance in small, medium-sized and large firms

    OpenAIRE

    Wu, N; Hoque, K.; Bacon, N.; Bou Llusar, JC

    2015-01-01

    This paper draws on the Organisational Growth and Development (OGD) lifecycle model to extend understanding of congruence or ‘best fit’ theory within strategic human resource management (SHRM) debates on the relationship between high performance work systems (HPWS) and performance. With reference to management control theory, economies of scale and the availability of specialist managerial skills, the paper hypothesises that while an HPWS-performance relationship might exist in small, medium-...

  10. Unlocking the Black Box: Exploring the Link between High-Performance Work Systems and Performance

    Science.gov (United States)

    Messersmith, Jake G.; Patel, Pankaj C.; Lepak, David P.

    2011-01-01

    With a growing body of literature linking systems of high-performance work practices to organizational performance outcomes, recent research has pushed for examinations of the underlying mechanisms that enable this connection. In this study, based on a large sample of Welsh public-sector employees, we explored the role of several individual-level…

  11. Optical interconnection networks for high-performance computing systems.

    Science.gov (United States)

    Biberman, Aleksandr; Bergman, Keren

    2012-04-01

    Enabled by silicon photonic technology, optical interconnection networks have the potential to be a key disruptive technology in computing and communication industries. The enduring pursuit of performance gains in computing, combined with stringent power constraints, has fostered the ever-growing computational parallelism associated with chip multiprocessors, memory systems, high-performance computing systems and data centers. Sustaining these parallelism growths introduces unique challenges for on- and off-chip communications, shifting the focus toward novel and fundamentally different communication approaches. Chip-scale photonic interconnection networks, enabled by high-performance silicon photonic devices, offer unprecedented bandwidth scalability with reduced power consumption. We demonstrate that the silicon photonic platforms have already produced all the high-performance photonic devices required to realize these types of networks. Through extensive empirical characterization in much of our work, we demonstrate such feasibility of waveguides, modulators, switches and photodetectors. We also demonstrate systems that simultaneously combine many functionalities to achieve more complex building blocks. We propose novel silicon photonic devices, subsystems, network topologies and architectures to enable unprecedented performance of these photonic interconnection networks. Furthermore, the advantages of photonic interconnection networks extend far beyond the chip, offering advanced communication environments for memory systems, high-performance computing systems, and data centers.

  12. Two failures to replicate high-performance-goal priming effects.

    Directory of Open Access Journals (Sweden)

    Christine R Harris

    Full Text Available Bargh et al. (2001 reported two experiments in which people were exposed to words related to achievement (e.g., strive, attain or to neutral words, and then performed a demanding cognitive task. Performance on the task was enhanced after exposure to the achievement related words. Bargh and colleagues concluded that better performance was due to the achievement words having activated a "high-performance goal". Because the paper has been cited well over 1100 times, an attempt to replicate its findings would seem warranted. Two direct replication attempts were performed. Results from the first experiment (n = 98 found no effect of priming, and the means were in the opposite direction from those reported by Bargh and colleagues. The second experiment followed up on the observation by Bargh et al. (2001 that high-performance-goal priming was enhanced by a 5-minute delay between priming and test. Adding such a delay, we still found no evidence for high-performance-goal priming (n = 66. These failures to replicate, along with other recent results, suggest that the literature on goal priming requires some skeptical scrutiny.

  13. Superior oxygen reduction electrocatalysis enabled by integrating hierarchical pores, Fe3C nanoparticles and bamboo-like carbon nanotubes

    Science.gov (United States)

    Yang, Wenxiu; Yue, Xiaoyu; Liu, Xiangjian; Chen, Lulu; Jia, Jianbo; Guo, Shaojun

    2015-12-01

    Hierarchical porous carbon nanostructures doped with nitrogen or other active elements have been demonstrated to be of importance in enhancing the oxygen reduction reaction (ORR) activity. However, their intrinsic limited active sites usually make them exhibit lower ORR activity than commercial Pt/C. In order to solve well this challenging issue, herein we develop a simple method for encapsulating more electrochemically active Fe3C nanoparticles (NPs) into the channels of bamboo-like carbon nanotubes (bCNTs) with interesting 3D hierarchical micro-, meso- and macropores by impregnating the bCNTs with a Fe(NO3)3 solution, followed by the calcination of the composite under a N2 atmosphere. The resulting bCNT/Fe3C hybrid electrocatalysts with much more active sites exhibit excellent ORR activity in acidic media with the half-wave potential of 0.710 V comparable to the commercial Pt/C catalyst (0.782 V). Furthermore, they show very high ORR activity in 0.10 M KOH with the half-wave potential of 0.879 V, 67 mV more positive than that of the Pt/C catalyst. Most importantly, the as-prepared new catalysts are very stable for ORR in both acidic and alkaline solutions with almost no ORR polarization curve shift after 3000 cycles, much better than that of the Pt/C catalyst. To the best of our knowledge, our new bCNT/Fe3C catalyst is the best non-noble-metal catalyst ever reported for ORR under both acidic and alkaline conditions. The present work highlights the important roles of introducing more stable Fe3C NPs and hierarchical micro-, meso- and macropores as much more active sites in maximizing the ORR electrocatalysis performance.Hierarchical porous carbon nanostructures doped with nitrogen or other active elements have been demonstrated to be of importance in enhancing the oxygen reduction reaction (ORR) activity. However, their intrinsic limited active sites usually make them exhibit lower ORR activity than commercial Pt/C. In order to solve well this challenging issue

  14. Phonons in A3C60 Lattice and Structural Dynamics

    Directory of Open Access Journals (Sweden)

    Sven Larsson

    2010-01-01

    Full Text Available The critical temperature ( of superconductivity in A3C60 compounds is generally lower smaller with alkali atoms (A. Furthermore decreases with applied pressure. In the BCS model, these trends are explained by the lower density of states at the Fermi level for a decreased lattice constant (R. There is more than one counterexample, however, suggesting that BCS does not give the whole truth. The most important one is that the compound with the largest lattice constant, Cs3C60, is not superconducting at all at ambient pressure. In this paper we derive a novel model where a negative lattice contribution to Hubbard U, proportional to 1/R, is taken into account. It is possible to explain why A3C60 compounds with A = Li, and Na have a low or are not superconducting at all, and why Cs3C60 is superconducting only at applied pressure and then with the highest of all C60 alkali fullerides. It is concluded that the density of states mechanism derived in the BCS model is in doubt. Nevertheless superconductivity in A3C60 depends on electron-phonon coupling. The dominating phonon is the bond stretching Ag phonon, a breathing phonon for the whole fullerene molecular ion.

  15. Chronic Pancreatitis, Type 3c Diabetes, and Pancreatic Cancer Risk

    Directory of Open Access Journals (Sweden)

    David C Whitcomb

    2014-09-01

    Full Text Available About half of all patients with chronic pancreatitis (CP develop diabetes mellitus (DM due to the loss of islet cell mass, not just beta cells as in Type 1 DM (T1DM, or due to insulin resistance, as in Type 2 DM (T2DM. Patients with DM from loss of islets due to pancreatic disease or resection are diagnosed with pancreatogenic or Type 3c DM (T3cDM. Patients with T3cDM also lose counter-regulatory hormones, such as glucagon and pancreatic polypeptide, and experience maldigestion associated with pancreatic exocrine insufficiency. Patients with T3cDM are therefore more susceptible to hypoglycemia and a mismatch (asynchrony between food ingestion and nutrient absorption. At the same time, the use of incretin therapy is likely useless, since maldigestion leads to the release of higher levels of hind gut hormones, including GLP1. Thus, T3cDM caused by CP or destruction of the islets involves a special class of potential risks and comorbidity that may be overlooked if the CP has not been diagnosed.

  16. Resource estimation in high performance medical image computing.

    Science.gov (United States)

    Banalagay, Rueben; Covington, Kelsie Jade; Wilkes, D M; Landman, Bennett A

    2014-10-01

    Medical imaging analysis processes often involve the concatenation of many steps (e.g., multi-stage scripts) to integrate and realize advancements from image acquisition, image processing, and computational analysis. With the dramatic increase in data size for medical imaging studies (e.g., improved resolution, higher throughput acquisition, shared databases), interesting study designs are becoming intractable or impractical on individual workstations and servers. Modern pipeline environments provide control structures to distribute computational load in high performance computing (HPC) environments. However, high performance computing environments are often shared resources, and scheduling computation across these resources necessitates higher level modeling of resource utilization. Submission of 'jobs' requires an estimate of the CPU runtime and memory usage. The resource requirements for medical image processing algorithms are difficult to predict since the requirements can vary greatly between different machines, different execution instances, and different data inputs. Poor resource estimates can lead to wasted resources in high performance environments due to incomplete executions and extended queue wait times. Hence, resource estimation is becoming a major hurdle for medical image processing algorithms to efficiently leverage high performance computing environments. Herein, we present our implementation of a resource estimation system to overcome these difficulties and ultimately provide users with the ability to more efficiently utilize high performance computing resources.

  17. High Performance Computing in Science and Engineering '16 : Transactions of the High Performance Computing Center, Stuttgart (HLRS) 2016

    CERN Document Server

    Kröner, Dietmar; Resch, Michael

    2016-01-01

    This book presents the state-of-the-art in supercomputer simulation. It includes the latest findings from leading researchers using systems from the High Performance Computing Center Stuttgart (HLRS) in 2016. The reports cover all fields of computational science and engineering ranging from CFD to computational physics and from chemistry to computer science with a special emphasis on industrially relevant applications. Presenting findings of one of Europe’s leading systems, this volume covers a wide variety of applications that deliver a high level of sustained performance. The book covers the main methods in high-performance computing. Its outstanding results in achieving the best performance for production codes are of particular interest for both scientists and engineers. The book comes with a wealth of color illustrations and tables of results.

  18. Design of High Performance Permanent-Magnet Synchronous Wind Generators

    Directory of Open Access Journals (Sweden)

    Chun-Yu Hsiao

    2014-11-01

    Full Text Available This paper is devoted to the analysis and design of high performance permanent-magnet synchronous wind generators (PSWGs. A systematic and sequential methodology for the design of PMSGs is proposed with a high performance wind generator as a design model. Aiming at high induced voltage, low harmonic distortion as well as high generator efficiency, optimal generator parameters such as pole-arc to pole-pitch ratio and stator-slot-shoes dimension, etc. are determined with the proposed technique using Maxwell 2-D, Matlab software and the Taguchi method. The proposed double three-phase and six-phase winding configurations, which consist of six windings in the stator, can provide evenly distributed current for versatile applications regarding the voltage and current demands for practical consideration. Specifically, windings are connected in series to increase the output voltage at low wind speed, and in parallel during high wind speed to generate electricity even when either one winding fails, thereby enhancing the reliability as well. A PMSG is designed and implemented based on the proposed method. When the simulation is performed with a 6 Ω load, the output power for the double three-phase winding and six-phase winding are correspondingly 10.64 and 11.13 kW. In addition, 24 Ω load experiments show that the efficiencies of double three-phase winding and six-phase winding are 96.56% and 98.54%, respectively, verifying the proposed high performance operation.

  19. Reliable Generation of High-Performance Matrix Algebra

    CERN Document Server

    Belter, Geoffrey; Nelson, Thomas; Norris, Boyana; Siek, Jeremy G

    2012-01-01

    Scientific programmers often turn to vendor-tuned Basic Linear Algebra Subprograms (BLAS) to obtain portable high performance. However, many numerical algorithms require several BLAS calls in sequence, and those successive calls result in suboptimal performance. The entire sequence needs to be optimized in concert. Instead of vendor-tuned BLAS, a programmer could start with source code in Fortran or C (e.g., based on the Netlib BLAS) and use a state-of-the-art optimizing compiler. However, our experiments show that optimizing compilers often attain only one-quarter the performance of hand-optimized code. In this paper we present a domain-specific compiler for matrix algebra, the Build to Order BLAS (BTO), that reliably achieves high performance using a scalable search algorithm for choosing the best combination of loop fusion, array contraction, and multithreading for data parallelism. The BTO compiler generates code that is between 16% slower and 39% faster than hand-optimized code.

  20. Flexible nanoscale high-performance FinFETs

    KAUST Repository

    Sevilla, Galo T.

    2014-10-28

    With the emergence of the Internet of Things (IoT), flexible high-performance nanoscale electronics are more desired. At the moment, FinFET is the most advanced transistor architecture used in the state-of-the-art microprocessors. Therefore, we show a soft-etch based substrate thinning process to transform silicon-on-insulator (SOI) based nanoscale FinFET into flexible FinFET and then conduct comprehensive electrical characterization under various bending conditions to understand its electrical performance. Our study shows that back-etch based substrate thinning process is gentler than traditional abrasive back-grinding process; it can attain ultraflexibility and the electrical characteristics of the flexible nanoscale FinFET show no performance degradation compared to its rigid bulk counterpart indicating its readiness to be used for flexible high-performance electronics.

  1. Superior oxygen reduction electrocatalysis enabled by integrating hierarchical pores, Fe3C nanoparticles and bamboo-like carbon nanotubes.

    Science.gov (United States)

    Yang, Wenxiu; Yue, Xiaoyu; Liu, Xiangjian; Chen, Lulu; Jia, Jianbo; Guo, Shaojun

    2016-01-14

    Hierarchical porous carbon nanostructures doped with nitrogen or other active elements have been demonstrated to be of importance in enhancing the oxygen reduction reaction (ORR) activity. However, their intrinsic limited active sites usually make them exhibit lower ORR activity than commercial Pt/C. In order to solve well this challenging issue, herein we develop a simple method for encapsulating more electrochemically active Fe3C nanoparticles (NPs) into the channels of bamboo-like carbon nanotubes (bCNTs) with interesting 3D hierarchical micro-, meso- and macropores by impregnating the bCNTs with a Fe(NO3)3 solution, followed by the calcination of the composite under a N2 atmosphere. The resulting bCNT/Fe3C hybrid electrocatalysts with much more active sites exhibit excellent ORR activity in acidic media with the half-wave potential of 0.710 V comparable to the commercial Pt/C catalyst (0.782 V). Furthermore, they show very high ORR activity in 0.10 M KOH with the half-wave potential of 0.879 V, 67 mV more positive than that of the Pt/C catalyst. Most importantly, the as-prepared new catalysts are very stable for ORR in both acidic and alkaline solutions with almost no ORR polarization curve shift after 3000 cycles, much better than that of the Pt/C catalyst. To the best of our knowledge, our new bCNT/Fe3C catalyst is the best non-noble-metal catalyst ever reported for ORR under both acidic and alkaline conditions. The present work highlights the important roles of introducing more stable Fe3C NPs and hierarchical micro-, meso- and macropores as much more active sites in maximizing the ORR electrocatalysis performance.

  2. Family and academic performance: identifying high school student profiles

    Directory of Open Access Journals (Sweden)

    Alicia Aleli Chaparro Caso López

    2016-01-01

    Full Text Available The objective of this study was to identify profiles of high school students, based on variables related to academic performance, socioeconomic status, cultural capital and family organization. A total of 21,724 high school students, from the five municipalities of the state of Baja California, took part. A K-means cluster analysis was performed to identify the profiles. The analyses identified two clearly-defined clusters: Cluster 1 grouped together students with high academic performance and who achieved higher scores for socioeconomic status, cultural capital and family involvement, whereas Cluster 2 brought together students with low academic achievement, and who also obtained lower scores for socioeconomic status and cultural capital, and had less family involvement. It is concluded that the family variables analyzed form student profiles that can be related to academic achievement.

  3. Software Tools for High-Performance Computiing: Survey and Recommendations

    Directory of Open Access Journals (Sweden)

    Bill Appelbe

    1996-01-01

    Full Text Available Applications programming for high-performance computing is notoriously difficult. Al-though parallel programming is intrinsically complex, the principal reason why high-performance computing is difficult is the lack of effective software tools. We believe that the lack of tools in turn is largely due to market forces rather than our inability to design and build such tools. Unfortunately, the poor availability and utilization of parallel tools hurt the entire supercomputing industry and the U.S. high performance computing initiative which is focused on applications. A disproportionate amount of resources is being spent on faster hardware and architectures, while tools are being neglected. This article introduces a taxonomy of tools, analyzes the major factors that contribute to this situation, and suggests ways that the imbalance could be redressed and the likely evolution of tools.

  4. High voltage stability performance of a gamma ray detection device

    Science.gov (United States)

    Abdullah, Nor Arymaswati; Lombigit, Lojius; Rahman, Nur Aira Abd

    2014-02-01

    An industrial grade digital radiation survey meter device is currently being developed at Malaysian Nuclear Agency. This device used a cylindrical type Geiger Mueller (GM) which acts as a detector. GM detector operates at relatively high direct current voltages depend on the type of GM tube. This thin/thick walled cylindrical type of GM tube operates at 450-650 volts range. Proper value and stability performance of high voltage are important parameters to ensure that this device give a reliable radiation dose measurement. This paper will present an assessment of the stability and performance of the high voltage supply for radiation detector. The assessment is performed using System Identification tools box in MATLAB and mathematical statistics.

  5. High Performance Ethernet Packet Processor Core for Next Generation Networks

    Directory of Open Access Journals (Sweden)

    Raja Jitendra Nayaka

    2012-10-01

    Full Text Available As the demand for high speed Internet significantly increasing to meet the requirement of large datatransfers, real-time communication and High Definition ( HD multimedia transfer over IP, the IP basednetwork products architecture must evolve and change. Application specific processors require highperformance, low power and high degree of programmability is the limitation in many general processorbased applications. This paper describes the design of Ethernet packet processor for system-on-chip (SoCwhich performs all core packet processing functions, including segmentation and reassembly, packetizationclassification, route and queue management which will speedup switching/routing performance making itmore suitable for Next Generation Networks (NGN. Ethernet packet processor design can be configuredfor use with multiple projects targeted to a FPGA device the system is designed to support 1/10/20/40/100Gigabit links with a speed and performance advantage. VHDL has been used to implement and simulatedthe required functions in FPGA.

  6. Achieving High Performance on the i860 Microprocessor

    Science.gov (United States)

    Lee, King; Kutler, Paul (Technical Monitor)

    1998-01-01

    The i860 is a high performance microprocessor used in the Intel Touchstone project. This paper proposes a paradigm for programming the i860 that is modelled on the vector instructions of the Cray computers. Fortran callable assembler subroutines were written that mimic the concurrent vector instructions of the Cray. Cache takes the place of vector registers. Using this paradigm we have achieved twice the performance of compiled code on a traditional solve.

  7. High performance APCS conceptual design and evaluation scoping study

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, N.; Liekhus, K.; Chambers, A.; Anderson, G.

    1998-02-01

    This Air Pollution Control System (APCS) Conceptual Design and Evaluation study was conducted to evaluate a high-performance (APC) system for minimizing air emissions from mixed waste thermal treatment systems. Seven variations of high-performance APCS designs were conceptualized using several design objectives. One of the system designs was selected for detailed process simulation using ASPEN PLUS to determine material and energy balances and evaluate performance. Installed system capital costs were also estimated. Sensitivity studies were conducted to evaluate the incremental cost and benefit of added carbon adsorber beds for mercury control, specific catalytic reduction for NO{sub x} control, and offgas retention tanks for holding the offgas until sample analysis is conducted to verify that the offgas meets emission limits. Results show that the high-performance dry-wet APCS can easily meet all expected emission limits except for possibly mercury. The capability to achieve high levels of mercury control (potentially necessary for thermally treating some DOE mixed streams) could not be validated using current performance data for mercury control technologies. The engineering approach and ASPEN PLUS modeling tool developed and used in this study identified APC equipment and system performance, size, cost, and other issues that are not yet resolved. These issues need to be addressed in feasibility studies and conceptual designs for new facilities or for determining how to modify existing facilities to meet expected emission limits. The ASPEN PLUS process simulation with current and refined input assumptions and calculations can be used to provide system performance information for decision-making, identifying best options, estimating costs, reducing the potential for emission violations, providing information needed for waste flow analysis, incorporating new APCS technologies in existing designs, or performing facility design and permitting activities.

  8. Performance evaluation of two highly interconnected Data Center networks

    DEFF Research Database (Denmark)

    Andrus, Bogdan-Mihai; Mihai Poncea, Ovidiu; Vegas Olmos, Juan José;

    2015-01-01

    In this paper we present the analysis of highly interconnected topologies like hypercube and torus and how they can be implemented in data centers in order to cope with the rapid increase and demands for performance of the internal traffic. By replicating the topologies and subjecting them...... of the network was increased by a factor of 32. The performance measurements are supported by abstract metrics that also give a cost and complexity indication in choosing the right topology for the required application....

  9. Capillary flow of amorphous metal for high performance electrode

    OpenAIRE

    Se Yun Kim; Suk Jun Kim; Sang Soo Jee; Jin Man Park; Keum Hwan Park; Sung Chan Park; Eun Ae Cho; Jun Ho Lee; In Yong Song; Sang Mock Lee; In Taek Han; Ka Ram Lim; Won Tae Kim; Ju Cheol Park; Jürgen Eckert

    2013-01-01

    Metallic glass (MG) assists electrical contact of screen-printed silver electrodes and leads to comparable electrode performance to that of electroplated electrodes. For high electrode performance, MG needs to be infiltrated into nanometer-scale cavities between Ag particles and reacts with them. Here, we show that the MG in the supercooled state can fill the gap between Ag particles within a remarkably short time due to capillary effect. The flow behavior of the MG is revealed by computation...

  10. Optimum selection of high performance mirror substrates for diamond finishing

    Science.gov (United States)

    Woodard, Kenneth S.; Comstock, Lovell E.; Wamboldt, Leonard; Sutherland, James S.

    2016-05-01

    Due to advances in manufacturing processes, the substrate options for high performance diamond machined mirrors are expanding. Fewer compromises have to be made to achieve the needed weight, stiffness and finish while maintaining reasonable costs. In addition to the traditional mirror materials like aluminum and beryllium, there are some less common materials that can now be included in the trade space that fill the cost and performance continuum between wrought aluminum and beryllium mirrors. Aluminum and beryllium, respectively, had been the low cost/fair performance and very high cost/very high performance bounds for substrate selection. These additional substrates provide multiple near net shape blank options and processes, mostly within these bounds, that can be considered in a mirror cost versus performance trade analysis. This paper will include a summary of some advances in manufacturing processes that provide more substrate options for diamond machined mirrors with some sample performance analysis and data. This is merged with the traditional substrate options to illustrate the now larger mirror substrate trade space. Some benchmark structural analysis is provided to back up a generic mirror design trade study.

  11. High Performance Walls in Hot-Dry Climates

    Energy Technology Data Exchange (ETDEWEB)

    Hoeschele, Marc [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Springer, David [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Dakin, Bill [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); German, Alea [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2015-01-01

    High performance walls represent a high priority measure for moving the next generation of new homes to the Zero Net Energy performance level. The primary goal in improving wall thermal performance revolves around increasing the wall framing from 2x4 to 2x6, adding more cavity and exterior rigid insulation, achieving insulation installation criteria meeting ENERGY STAR's thermal bypass checklist. To support this activity, in 2013 the Pacific Gas & Electric Company initiated a project with Davis Energy Group (lead for the Building America team, Alliance for Residential Building Innovation) to solicit builder involvement in California to participate in field demonstrations of high performance wall systems. Builders were given incentives and design support in exchange for providing site access for construction observation, cost information, and builder survey feedback. Information from the project was designed to feed into the 2016 Title 24 process, but also to serve as an initial mechanism to engage builders in more high performance construction strategies. This Building America project utilized information collected in the California project.

  12. New infrared spectral component of the quasar 3C273

    Energy Technology Data Exchange (ETDEWEB)

    Robson, E.I.; Gear, W.K.; Brown, L.M.J.; Courvoisier, T.J.-L.; Smith, M.G.; Griffin, M.J.; Blecha, A.

    1986-09-11

    Following the dramatic infrared to millimetre-wavelength flare seen in the quasar 3C273 during 1983, the authors have continued to monitor its overall continuum emission. Recent measurements show that the 10-..mu..m to 3-mm emission has decayed to a level well below any seen previously, while the 1-4-..mu..m emission has remained relatively constant. This behaviour has revealed the presence of an apparently non-variable component which dominates the near-infrared emission in 3C273 and includes the small 'bump' at approx. 3.5 ..mu..m in the power-law continuum.

  13. Path-integral molecular dynamics simulation of 3C-SiC

    Science.gov (United States)

    Ramírez, Rafael; Herrero, Carlos P.; Hernández, Eduardo R.; Cardona, Manuel

    2008-01-01

    Molecular dynamics simulations of 3C-SiC have been performed as a function of pressure and temperature. These simulations treat both electrons and atomic nuclei by quantum mechanical methods. While the electronic structure of the solid is described by an efficient tight-binding Hamiltonian, the nuclei dynamics is treated by the path-integral formulation of statistical mechanics. To assess the relevance of nuclear quantum effects, the results of quantum simulations are compared to others where either the Si nuclei, the C nuclei, or both atomic nuclei are treated as classical particles. We find that the experimental thermal expansion of 3C-SiC is realistically reproduced by our simulations. The calculated bulk modulus of 3C-SiC and its pressure derivative at room temperature show also good agreement with the available experimental data. The effect of the electron-phonon interaction on the direct electronic gap of 3C-SiC has been calculated as a function of temperature and related to results obtained for bulk diamond and Si. Comparison to available experimental data shows satisfactory agreement, although we observe that the employed tight-binding model tends to overestimate the magnitude of the electron-phonon interaction. The effect of treating the atomic nuclei as classical particles on the direct gap of 3C-SiC has been assessed. We find that nonlinear quantum effects related to the atomic masses are particularly relevant at temperatures below 250K .

  14. Comparative performance of wavelets and JPEG coders at high quality

    Science.gov (United States)

    Algazi, V. Ralph; Estes, Robert R., Jr.

    1997-04-01

    In recent work, we have examined the performance of wavelet coders using a perceptually relevant image quality metric, the picture quality scale (PQS). In that study, we considered some of the design options available with respect to choice of wavelet basis, quantizer, and method for error- free encoding of the quantized coefficients, including the EZW methodology. A specific combination of these design options provides the best trade off between performance and PQS quality. Here, we extend this comparison by evaluating the performance of JPEG and the previously chosen optimal wavelet scheme, focusing principally on the high quality range.

  15. High Performance Flat Plate Solar Thermal Collector Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Rockenbaugh, Caleb [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dean, Jesse [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lovullo, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lisell, Lars [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barker, Greg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hanckock, Ed [National Renewable Energy Lab. (NREL), Golden, CO (United States); Norton, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    This report was prepared for the General Services Administration by the National Renewable Energy Laboratory. The Honeycomb Solar Thermal Collector (HSTC) is a flat plate solar thermal collector that shows promising high efficiencies over a wide range of climate zones. The technical objectives of this study are to: 1) verify collector performance, 2) compare that performance to other market-available collectors, 3) verify overheat protection, and 4) analyze the economic performance of the HSTC both at the demonstration sites and across a matrix of climate zones and utility markets.

  16. Performance of high-rate gravel-packed oil wells

    Energy Technology Data Exchange (ETDEWEB)

    Unneland, Trond

    2001-05-01

    Improved methods for the prediction, evaluation, and monitoring of performance in high-rate cased-hole gravel-packed oil wells are presented in this thesis. The ability to predict well performance prior to the gravel-pack operations, evaluate the results after the operation, and monitor well performance over time has been improved. This lifetime approach to performance analysis of gravel-packed oil wells contributes to increase oil production and field profitability. First, analytical models available for prediction of performance in gravel-packed oil wells are reviewed, with particular emphasis on high-velocity flow effects. From the analysis of field data from three North Sea oil fields, improved and calibrated cased-hole gravel-pack performance prediction models are presented. The recommended model is based on serial flow through formation sand and gravel in the perforation tunnels. In addition, new correlations for high-velocity flow in high-rate gravel-packed oil wells are introduced. Combined, this improves the performance prediction for gravel-packed oil wells, and specific areas can be targeted for optimized well design. Next, limitations in the current methods and alternative methods for evaluation and comparison of well performance are presented. The most widely used parameter, the skin factor, remains a convenient and important parameter. However, using the skin concept in direct comparisons between wells with different reservoir properties may result in misleading or even invalid conclusions. A discussion of the parameters affecting the skin value, with a clarification of limitations, is included. A methodology for evaluation and comparison of gravel-packed well performance is presented, and this includes the use of results from production logs and the use of effective perforation tunnel permeability as a parameter. This contributes to optimized operational procedures from well to well and from field to field. Finally, the data sources available for

  17. High-performance silicon photonics technology for telecommunications applications.

    Science.gov (United States)

    Yamada, Koji; Tsuchizawa, Tai; Nishi, Hidetaka; Kou, Rai; Hiraki, Tatsurou; Takeda, Kotaro; Fukuda, Hiroshi; Ishikawa, Yasuhiko; Wada, Kazumi; Yamamoto, Tsuyoshi

    2014-04-01

    By way of a brief review of Si photonics technology, we show that significant improvements in device performance are necessary for practical telecommunications applications. In order to improve device performance in Si photonics, we have developed a Si-Ge-silica monolithic integration platform, on which compact Si-Ge-based modulators/detectors and silica-based high-performance wavelength filters are monolithically integrated. The platform features low-temperature silica film deposition, which cannot damage Si-Ge-based active devices. Using this platform, we have developed various integrated photonic devices for broadband telecommunications applications.

  18. Structures and energies of Cu clusters on Fe and Fe3C surfaces from density functional theory computation.

    Science.gov (United States)

    Tian, Xinxin; Wang, Tao; Yang, Yong; Li, Yong-Wang; Wang, Jianguo; Jiao, Haijun

    2014-12-28

    Spin-polarized density functional theory computations have been carried out to study the stable adsorption configurations of Cun (n = 1-7, 13) on Fe and Fe3C surfaces for understanding the initial stages of copper promotion in catalysis. At low coverage, two-dimensional aggregation is more preferred over dispersion and three-dimensional aggregation on the Fe(110) and Fe(100) surfaces as well as the metallic Fe3C(010) surfaces, while dispersion is more favorable over aggregation on the Fe(111) surface. On the Fe3C(001) and Fe3C(100) surfaces with exposed iron and carbon atoms, the adsorbed Cu atoms prefer dispersion at low coverage, while aggregation along the iron regions at high coverage. On the iron surfaces, the adsorption energies of Cun (n = 2-7) are highest on Fe(111), medium on Fe(100) and lowest on Fe(110). On the Fe3C surfaces, the adsorption energies of Cun (n = 1-3) are highest on Fe3C(100), medium on Fe3C(010) and lowest on Fe3C(001), while, for n = 4-7 and 13, Fe3C(010) has stronger adsorption than Fe3C(100). On the basis of their differences in electronegativity, the adsorbed Cu atoms can oxidize the metallic Fe(110), Fe(100) and Fe3C(010) surfaces and become negatively charged. On the Fe3C(001) and Fe3C(100) surfaces with exposed iron and carbon atoms, the adsorbed Cu atoms interacting with surface carbon atoms are oxidized and positively charged. Unlike the most stable Fe(110) and Fe3C(001) surfaces, where the Fe(110) surface has stronger Cu affinity than the Fe3C(001) surface, which is in agreement with the experimental finding, the less and least stable Fe3C(010) and Fe3C(100) surfaces have stronger Cu affinities than the Fe(110) and Fe(100) surfaces. Since less stable facets are not preferably formed thermodynamically, it is crucial to prepare such surfaces to explore Cu adsorption and promotion, and this provides challenges to surface sciences.

  19. Visualization and Data Analysis for High-Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Sewell, Christopher Meyer [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-27

    This is a set of slides from a guest lecture for a class at the University of Texas, El Paso on visualization and data analysis for high-performance computing. The topics covered are the following: trends in high-performance computing; scientific visualization, such as OpenGL, ray tracing and volume rendering, VTK, and ParaView; data science at scale, such as in-situ visualization, image databases, distributed memory parallelism, shared memory parallelism, VTK-m, "big data", and then an analysis example.

  20. Flex Fatigue Property and Fractography of High Performance Fibers

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hua-peng; LIU Xiao-yan; SHI Mei-wu; ZHANG Jian-chun; LAI Kan; WANG Shan-yuan

    2002-01-01

    The effects of pre-stress and bending angle on the flex fatigue lifetimes of para- aramds have been studied choosing the Twaron 2000 high performance filament as the studying subject by use of the self-developed flex fatigue apparatus. The fractography of the fatiguebreaking end of the single filaments has been obtained and the fatigue-breaking mechanisms have been analyzed using the LM and SEM. The differences of the fatigue properties and fractography of a variety of high performance fibers such as Kevlar 129, Kevlar 29 and UHMW PE have been discussed.

  1. RESEARCH ON THE HIGH PERFORMANCE COMPOSITE ROAD CONCRETE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Ordinary concrete presents short service life when used for building and repairing high-grade road with heavy traffic due to its large brittleness, poor bending flexibility and serious shrinkage on drying. In this paper,a new kind of high performance concrete has been designed by means of combination of organic, inorganic material as well as metal material.The research and application have shown that this new concrete can significantly counteract the deficiency of ordinary concrete and give excellent mechanical properties and pavement performances. The application of this new kind of concrete is of great social and economic significance.

  2. High performance computing and communications: FY 1997 implementation plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The High Performance Computing and Communications (HPCC) Program was formally authorized by passage, with bipartisan support, of the High-Performance Computing Act of 1991, signed on December 9, 1991. The original Program, in which eight Federal agencies participated, has now grown to twelve agencies. This Plan provides a detailed description of the agencies` FY 1996 HPCC accomplishments and FY 1997 HPCC plans. Section 3 of this Plan provides an overview of the HPCC Program. Section 4 contains more detailed definitions of the Program Component Areas, with an emphasis on the overall directions and milestones planned for each PCA. Appendix A provides a detailed look at HPCC Program activities within each agency.

  3. GPU-based high-performance computing for radiation therapy.

    Science.gov (United States)

    Jia, Xun; Ziegenhein, Peter; Jiang, Steve B

    2014-02-21

    Recent developments in radiotherapy therapy demand high computation powers to solve challenging problems in a timely fashion in a clinical environment. The graphics processing unit (GPU), as an emerging high-performance computing platform, has been introduced to radiotherapy. It is particularly attractive due to its high computational power, small size, and low cost for facility deployment and maintenance. Over the past few years, GPU-based high-performance computing in radiotherapy has experienced rapid developments. A tremendous amount of study has been conducted, in which large acceleration factors compared with the conventional CPU platform have been observed. In this paper, we will first give a brief introduction to the GPU hardware structure and programming model. We will then review the current applications of GPU in major imaging-related and therapy-related problems encountered in radiotherapy. A comparison of GPU with other platforms will also be presented.

  4. An Object Oriented and High Performance Platform for Aerothermodynamics Simulation

    OpenAIRE

    Lani, Andrea

    2008-01-01

    This thesis presents the author's contribution to the design and implementation of COOLFluiD,an object oriented software platform for the high performance simulation of multi-physics phenomena on unstructured grids. In this context, the final goal has been to provide a reliable tool for handling high speed aerothermodynamic applications. To this end, we introduce a number of design techniques that have been developed in order to provide the framework with flexibilityand reusability, allowing ...

  5. Dynamic Resource Management and Job Scheduling for High Performance Computing

    OpenAIRE

    2016-01-01

    Job scheduling and resource management plays an essential role in high-performance computing. Supercomputing resources are usually managed by a batch system, which is responsible for the effective mapping of jobs onto resources (i.e., compute nodes). From the system perspective, a batch system must ensure high system utilization and throughput, while from the user perspective it must ensure fast response times and fairness when allocating resources across jobs. Parallel jobs can be divide...

  6. Data of evolutionary structure change: 1V37A-2YW3C [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1V37A-2YW3C 1V37 2YW3 A C --------MELWLVRH--------GETLWNREGRLLGWT...41 ALA CA 498 2YW3 C 2YW3C...CA 453 2YW3 C 2YW3C.../pdbChain> 2YW3C LEITL-RTEKG EEE - HH...VID> 3 2YW3 C 2YW3C

  7. High performance flexible CMOS SOI FinFETs

    KAUST Repository

    Fahad, Hossain M.

    2014-06-01

    We demonstrate the first ever CMOS compatible soft etch back based high performance flexible CMOS SOI FinFETs. The move from planar to non-planar FinFETs has enabled continued scaling down to the 14 nm technology node. This has been possible due to the reduction in off-state leakage and reduced short channel effects on account of the superior electrostatic charge control of multiple gates. At the same time, flexible electronics is an exciting expansion opportunity for next generation electronics. However, a fully integrated low-cost system will need to maintain ultra-large-scale-integration density, high performance and reliability - same as today\\'s traditional electronics. Up until recently, this field has been mainly dominated by very weak performance organic electronics enabled by low temperature processes, conducive to low melting point plastics. Now however, we show the world\\'s highest performing flexible version of 3D FinFET CMOS using a state-of-the-art CMOS compatible fabrication technique for high performance ultra-mobile consumer applications with stylish design. © 2014 IEEE.

  8. The Double–Double Radio Galaxy 3C293

    Indian Academy of Sciences (India)

    S. A. Joshi; S. Nandi; D. J. Saikia; C. H. Ishwara-Chandra; C. Konar

    2011-12-01

    We present the results of radio continuum observations at frequencies ranging from ∼ 150–5000 MHz of the misaligned double–double radio galaxy (DDRG) 3C293 (J1352+3126) using the GMRT and the VLA, and estimate the time-scale of interruption of jet activity to be less than ∼ 0.1 Myr.

  9. Search for exotic events from the L3+C data

    Institute of Scientific and Technical Information of China (English)

    DING Lin-Kai; HE Zuo-Xiu; HUO An-Xiang; JING Cai-Liu; KUANG Hao-Huai; LEI Yu; LI Li; MA Xin-Hua; MA Yu-Qian; QING Cheng-Rui; WANG Rui-Guang; YAO Zhi-Guo; YU Zhong-Qiang; ZHANG Chao; ZHANG Feng; ZHANG Jing; ZHU Qing-Qi

    2009-01-01

    An effort to search for Kolar-like events within the data set of the L3+C experiment is reported. From a total of 0.89×1010 triggered events there are no reliable two-prong Kolar-like events observed. The some reasonable assumptions.

  10. A microelectromechanical system digital 3C array seismic cone penetrometer

    NARCIS (Netherlands)

    Ghose, R.

    2012-01-01

    A digital 3C array seismic cone penetrometer has been developed for multidisciplinary geophysical and geotechnical applications. Seven digital triaxial microelectromechanical system accelerometers are installed at 0.25-m intervals to make a 1.5-m-long downhole seismic array. The accelerometers have

  11. A decade of 3C technologies: insights into nuclear organization

    NARCIS (Netherlands)

    de Wit, E.; de Laat, W.

    2012-01-01

    Over the past 10 years, the development of chromosome conformation capture (3C) technology and the subsequent genomic variants thereof have enabled the analysis of nuclear organization at an unprecedented resolution and throughput. The technology relies on the original and, in hindsight, remarkably

  12. Discovery of a faint optical jet in 3C 120

    DEFF Research Database (Denmark)

    Hjorth, J.; Vestergaard, Marianne; Sorensen, A. N.;

    1995-01-01

    the optical condensation A of the galaxy, which includes the bright 4" radio knot, is found to be 12 % polarized with the electric field vectors perpendicular to the jet. These findings indicate that 3C 120 contains the 6th known extragalactic optical synchrotron jet, quite similar in its properties...

  13. Microwave Radiometer – 3 Channel (MWR3C) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Cadeddu, MP

    2012-05-04

    The microwave radiometer 3-channel (MWR3C) provides time-series measurements of brightness temperatures from three channels centered at 23.834, 30, and 89 GHz. These three channels are sensitive to the presence of liquid water and precipitable water vapor.

  14. QsNetII : Defining High-Performance Network Design

    Energy Technology Data Exchange (ETDEWEB)

    Beecroft, Jon; Addison, David; Hewson, David; McLaren, Moray; Roweth, Duncan; Petrini, Fabrizio; Nieplocha, Jarek

    2005-07-05

    Cluster computers—parallel computers built from commodity processors—are becoming the predominant supercomputer architecture because of their combined scalable performance and attractive price. As of June 2005, 61 percent of the world’s top-500 supercomputers were clusters (http://www.top500.org). This is a significant paradigm shift from a few decades ago, when supercomputers were special purpose, like the Cray vector machines, and designers built them from expensive, custom components. Clusters that use commodity processors still require high-performance, low-latency networks, if their applications are fine-grained, or if the cluster has many processors. Clusters can use commodity networks, such as Gigabit Ethernet, but these fall short in many scalability and performance aspects.1 Consequently, the core of several successful cluster-based supercomputers is a highperformance network. On the one hand, this component interfaces with standard I/O buses, such as peripheral component interconnect (PCI), its extended version (PCI-X), and PCI-Express, thus everaging commodity computing nodes. On the other hand, it provides scalable erformance and cluster aggregation through specialized protocols.2 Thus, in a sense, the high-performance network in a cluster computer is the computer because it largely defines achievable performance, widening the range of the applications a cluster can efficiently execute, as well as defining its scalability, fault tolerance, system software, and overall usability. Because of their key performance-enhancing role, cluster computer networks must meet high standards in four design spects—performance, scalability, reliability, and programmability. The “Four Critical Design Criteria” sidebar describes these in more detail. QsNetII, the latest generation Quadrics interconnect, meets these standards, extending previous work on high-performance networks with an aggressive design to achieve ultra-low latency. At the design’s core are

  15. Mallow carotenoids determined by high-performance liquid chromatography

    Science.gov (United States)

    Mallow (corchorus olitorius) is a green vegetable, which is widely consumed either fresh or dry by Middle East population. This study was carried out to determine the contents of major carotenoids quantitatively in mallow, by using a High Performance Liquid Chromatography (HPLC) equipped with a Bis...

  16. Determination of Caffeine in Beverages by High Performance Liquid Chromatography.

    Science.gov (United States)

    DiNunzio, James E.

    1985-01-01

    Describes the equipment, procedures, and results for the determination of caffeine in beverages by high performance liquid chromatography. The method is simple, fast, accurate, and, because sample preparation is minimal, it is well suited for use in a teaching laboratory. (JN)

  17. Multichannel Detection in High-Performance Liquid Chromatography.

    Science.gov (United States)

    Miller, James C.; And Others

    1982-01-01

    A linear photodiode array is used as the photodetector element in a new ultraviolet-visible detection system for high-performance liquid chromatography (HPLC). Using a computer network, the system processes eight different chromatographic signals simultaneously in real-time and acquires spectra manually/automatically. Applications in fast HPLC…

  18. High-Performance Liquid Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Vestal, Marvin L.

    1984-01-01

    Reviews techniques for online coupling of high-performance liquid chromatography with mass spectrometry, emphasizing those suitable for application to nonvolatile samples. Also summarizes the present status, strengths, and weaknesses of various techniques and discusses potential applications of recently developed techniques for combined liquid…

  19. Analysis of Tocopherols by High Performance Liquid Chromatography

    OpenAIRE

    Edison, B.

    2009-01-01

    : Gas chromatography is the key technique for organic components and also for tocopherols analysis. High performance liquid chromatography has an important role to take part in applications such as the handling of less usual samples, prevention of degradation of heat sensitive functional groups and for micro preparative purposes. Many approaches for development of improved methods are suggested, especially for reversed phase applications.

  20. Ultra high performance liquid chromatography of seized drugs

    NARCIS (Netherlands)

    Lurie, I.S.

    2010-01-01

    The primary goal of this thesis is to investigate the use of ultra high performance liquid chromatography (UHPLC) for the analysis of seized drugs. This goal was largely achieved and significant progress was made in achieving improved separation and detection of drugs of forensic interest.

  1. Replica-Based High-Performance Tuple Space Computing

    DEFF Research Database (Denmark)

    Andric, Marina; De Nicola, Rocco; Lluch Lafuente, Alberto

    2015-01-01

    We present the tuple-based coordination language RepliKlaim, which enriches Klaim with primitives for replica-aware coordination. Our overall goal is to offer suitable solutions to the challenging problems of data distribution and locality in large-scale high performance computing. In particular,...

  2. Quantification of Tea Flavonoids by High Performance Liquid Chromatography

    Science.gov (United States)

    Freeman, Jessica D.; Niemeyer, Emily D.

    2008-01-01

    We have developed a laboratory experiment that uses high performance liquid chromatography (HPLC) to quantify flavonoid levels in a variety of commercial teas. Specifically, this experiment analyzes a group of flavonoids known as catechins, plant-derived polyphenolic compounds commonly found in many foods and beverages, including green and black…

  3. Dynamic Social Networks in High Performance Football Coaching

    Science.gov (United States)

    Occhino, Joseph; Mallett, Cliff; Rynne, Steven

    2013-01-01

    Background: Sports coaching is largely a social activity where engagement with athletes and support staff can enhance the experiences for all involved. This paper examines how high performance football coaches develop knowledge through their interactions with others within a social learning theory framework. Purpose: The key purpose of this study…

  4. Developments on HNF based high performance and green solid propellants

    NARCIS (Netherlands)

    Keizers, H.L.J.; Heijden, A.E.D.M. van der; Vliet, L.D. van; Welland-Veltmans, W.H.M.; Ciucci, A.

    2001-01-01

    Worldwide developments are ongoing to develop new and more energetic composite solid propellant formulations for space transportation and military applications. Since the 90's, the use of HNF as a new high performance oxidiser is being reinvestigated. Within European development programmes, signific

  5. Training Needs for High Performance in the Automotive Industry.

    Science.gov (United States)

    Clyne, Barry; And Others

    A project was conducted in Australia to identify the training needs of the emerging industry required to support the development of the high performance areas of the automotive machining and reconditioning field especially as it pertained to auto racing. Data were gathered through a literature search, interviews with experts in the field, and…

  6. Sensitivity Study of Strapdown Inertial Sensors in High Performance Applications

    Science.gov (United States)

    1980-12-01

    system error varied with a change in heading 7K. ( xii 1 SENSITIVITY STUDY OF STRAPDOWN INERTIAL SENSORS IN HIGH PERFORMANCE APPLICATIONS I. Introduction...given in Tabla 10. 23 State Meaning o Basic Altitude Damped INS x(1) Error in East Longitude 5.7735 x 1O Ŗ arc min x(2) Error in North Latitude

  7. Teacher and Leader Effectiveness in High-Performing Education Systems

    Science.gov (United States)

    Darling-Hammond, Linda, Ed.; Rothman, Robert, Ed.

    2011-01-01

    The issue of teacher effectiveness has risen rapidly to the top of the education policy agenda, and the federal government and states are considering bold steps to improve teacher and leader effectiveness. One place to look for ideas is the experiences of high-performing education systems around the world. Finland, Ontario, and Singapore all have…

  8. Managing School Districts for High Performance: Instructor's Guide

    Science.gov (United States)

    Childress, Stacey, Ed.; Elmore, Richard F., Ed.; Grossman, Allen, Ed.; Johnson, Susan Moore, Ed.

    2007-01-01

    This companion Instructor's Guide to "Managing School Districts for High Performance: Cases in Public Education Leadership" includes detailed teaching notes on each case in the coursebook, with an emphasis on making cases drawn from other disciplines relevant to education administrators. Both experienced instructors and those new to the…

  9. Enabling High-Performance Computing as a Service

    KAUST Repository

    AbdelBaky, Moustafa

    2012-10-01

    With the right software infrastructure, clouds can provide scientists with as a service access to high-performance computing resources. An award-winning prototype framework transforms the Blue Gene/P system into an elastic cloud to run a representative HPC application. © 2012 IEEE.

  10. High-performance inhoudsstoffen vinden hun weg naar de markt

    NARCIS (Netherlands)

    Meer, van der I.M.; Vollebregt, M.

    2015-01-01

    High-performance inhoudsstoffen uit biomassa ontstijgen de onderzoekslaboratoria en duiken op in proefprojecten met bedrijven en concrete toepassingen in eindproducten. Het tempo waarmee dit gebeurt en de onderliggende markt drivers verschillen per productgebied, zo blijkt uit een rondje langs bioba

  11. Seeking Solution: High-Performance Computing for Science. Background Paper.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Office of Technology Assessment.

    This is the second publication from the Office of Technology Assessment's assessment on information technology and research, which was requested by the House Committee on Science and Technology and the Senate Committee on Commerce, Science, and Transportation. The first background paper, "High Performance Computing & Networking for…

  12. The high-producing dairy cow and its reproductive performance

    DEFF Research Database (Denmark)

    Dobson, H; Smith, Rf; Royal, Md;

    2007-01-01

    There is evidence that the reproductive performance of dairy cows has declined as milk yields have increased over the last 40 years. Identifying the precise cause(s) of this problem may provide focused solutions. Intensive genetic selection for very high yields has reduced fertility, due mainly t...

  13. High performance fuel electrode for a solid oxide electrochemical cell

    DEFF Research Database (Denmark)

    2013-01-01

    A high performance anode (fuel electrode) for use in a solid oxide electrochemical cell is obtained by a process comprising the steps of (a) providing a suitably doped, stabilized zirconium oxide electrolyte, such as YSZ,ScYSZ, with an anode side having a coating of electronically conductive...

  14. Design methodology to enhance high impedance surfaces performances

    Directory of Open Access Journals (Sweden)

    Michael Grelier

    2014-04-01

    Full Text Available A methodology is introduced for designing wideband, compact and ultra-thin high impedance surfaces (HIS. A parametric study is carried out to examine the effect of the periodicity on the electromagnetic properties of an HIS. This approach allows designers to reach the best trade-off for HIS performances.

  15. The Case for High-Performance, Healthy Green Schools

    Science.gov (United States)

    Carter, Leesa

    2011-01-01

    When trying to reach their sustainability goals, schools and school districts often run into obstacles, including financing, training, and implementation tools. Last fall, the U.S. Green Building Council-Georgia (USGBC-Georgia) launched its High Performance, Healthy Schools (HPHS) Program to help Georgia schools overcome those obstacles. By…

  16. Computer science of the high performance; Informatica del alto rendimiento

    Energy Technology Data Exchange (ETDEWEB)

    Moraleda, A.

    2008-07-01

    The high performance computing is taking shape as a powerful accelerator of the process of innovation, to drastically reduce the waiting times for access to the results and the findings in a growing number of processes and activities as complex and important as medicine, genetics, pharmacology, environment, natural resources management or the simulation of complex processes in a wide variety of industries. (Author)

  17. High Performance Computing tools for the Integrated Tokamak Modelling project

    Energy Technology Data Exchange (ETDEWEB)

    Guillerminet, B., E-mail: bernard.guillerminet@cea.f [Association Euratom-CEA sur la Fusion, IRFM, DSM, CEA Cadarache (France); Plasencia, I. Campos [Instituto de Fisica de Cantabria (IFCA), CSIC, Santander (Spain); Haefele, M. [Universite Louis Pasteur, Strasbourg (France); Iannone, F. [EURATOM/ENEA Fusion Association, Frascati (Italy); Jackson, A. [University of Edinburgh (EPCC) (United Kingdom); Manduchi, G. [EURATOM/ENEA Fusion Association, Padova (Italy); Plociennik, M. [Poznan Supercomputing and Networking Center (PSNC) (Poland); Sonnendrucker, E. [Universite Louis Pasteur, Strasbourg (France); Strand, P. [Chalmers University of Technology (Sweden); Owsiak, M. [Poznan Supercomputing and Networking Center (PSNC) (Poland)

    2010-07-15

    Fusion Modelling and Simulation are very challenging and the High Performance Computing issues are addressed here. Toolset for jobs launching and scheduling, data communication and visualization have been developed by the EUFORIA project and used with a plasma edge simulation code.

  18. High-performance perovskite-graphene hybrid photodetector.

    Science.gov (United States)

    Lee, Youngbin; Kwon, Jeong; Hwang, Euyheon; Ra, Chang-Ho; Yoo, Won Jong; Ahn, Jong-Hyun; Park, Jong Hyeok; Cho, Jeong Ho

    2015-01-01

    A high-performance novel photodetector is demonstrated, which consists of graphene and CH3 NH3 PbI3 perovskite layers. The resulting hybrid photodetector exhibits a dramatically enhanced photo responsivity (180 A/W) and effective quantum efficiency (5× 10(4) %) over a broad bandwidth within the UV and visible ranges.

  19. Resolution of RNA using high-performance liquid chromatography

    NARCIS (Netherlands)

    Mclaughlin, L.W.; Bischoff, Rainer

    1987-01-01

    High-performance liquid chromatographic techniques can be very effective for the resolution and isolation of nucleic acids. The characteristic ionic (phosphodiesters) and hydrophobic (nucleobases) properties of RNAs can be exploited for their separation. In this respect anion-exchange and reversed-p

  20. Maintaining High-Performance Schools after Construction or Renovation

    Science.gov (United States)

    Luepke, Gary; Ronsivalli, Louis J., Jr.

    2009-01-01

    With taxpayers' considerable investment in schools, it is critical for school districts to preserve their community's assets with new construction or renovation and effective facility maintenance programs. "High-performance" school buildings are designed to link the physical environment to positive student achievement while providing such benefits…

  1. Frequency selective surfaces based high performance microstrip antenna

    CERN Document Server

    Narayan, Shiv; Jha, Rakesh Mohan

    2016-01-01

    This book focuses on performance enhancement of printed antennas using frequency selective surfaces (FSS) technology. The growing demand of stealth technology in strategic areas requires high-performance low-RCS (radar cross section) antennas. Such requirements may be accomplished by incorporating FSS into the antenna structure either in its ground plane or as the superstrate, due to the filter characteristics of FSS structure. In view of this, a novel approach based on FSS technology is presented in this book to enhance the performance of printed antennas including out-of-band structural RCS reduction. In this endeavor, the EM design of microstrip patch antennas (MPA) loaded with FSS-based (i) high impedance surface (HIS) ground plane, and (ii) the superstrates are discussed in detail. The EM analysis of proposed FSS-based antenna structures have been carried out using transmission line analogy, in combination with the reciprocity theorem. Further, various types of novel FSS structures are considered in desi...

  2. High Performance Nano-Ceria Electrodes for Solid Oxide Cells

    DEFF Research Database (Denmark)

    Graves, Christopher R.; Martinez Aguilera, Lev; Sudireddy, Bhaskar Reddy

    2016-01-01

    In solid oxide electrochemical cells, the conventional Ni-based fuel-electrodes provide high electrocatalytic activity but they are often a major source of long-term performance degradation due to carbon deposition, poisoning of reaction sites, Ni mobility, etc. Doped-ceria is a promising mixed...... ionic-electronic conducting oxide that could solve these issues if it can be integrated into an appropriate electrode structure. Two new approaches to obtain high-performance nanostructured doped-ceria electrodes are highlighted. The first is an infiltration-based architecture with Ce0.8Pr0.2O2-δ...... an unprecedented electrode polarization resistance of ~0.01 Ω cm2 at 650 °C in H2/H2O. These results demonstrate that nano-ceria has the ability to achieve higher performance than Ni-based electrodes and show that the main challenge is obtaining sufficient electronic current collection without adding too much...

  3. Building and measuring a high performance network architecture

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, William T.C.; Toole, Timothy; Fisher, Chuck; Dugan, Jon; Wheeler, David; Wing, William R; Nickless, William; Goddard, Gregory; Corbato, Steven; Love, E. Paul; Daspit, Paul; Edwards, Hal; Mercer, Linden; Koester, David; Decina, Basil; Dart, Eli; Paul Reisinger, Paul; Kurihara, Riki; Zekauskas, Matthew J; Plesset, Eric; Wulf, Julie; Luce, Douglas; Rogers, James; Duncan, Rex; Mauth, Jeffery

    2001-04-20

    Once a year, the SC conferences present a unique opportunity to create and build one of the most complex and highest performance networks in the world. At SC2000, large-scale and complex local and wide area networking connections were demonstrated, including large-scale distributed applications running on different architectures. This project was designed to use the unique opportunity presented at SC2000 to create a testbed network environment and then use that network to demonstrate and evaluate high performance computational and communication applications. This testbed was designed to incorporate many interoperable systems and services and was designed for measurement from the very beginning. The end results were key insights into how to use novel, high performance networking technologies and to accumulate measurements that will give insights into the networks of the future.

  4. High-Performance Image Synthesis for Radio Interferometry

    CERN Document Server

    Muscat, Daniel

    2014-01-01

    A radio interferometer indirectly measures the intensity distribution of the sky over the celestial sphere. Since measurements are made over an irregularly sampled Fourier plane, synthesising an intensity image from interferometric measurements requires substantial processing. Furthermore there are distortions that have to be corrected. In this thesis, a new high-performance image synthesis tool (imaging tool) for radio interferometry is developed. Implemented in C++ and CUDA, the imaging tool achieves unprecedented performance by means of Graphics Processing Units (GPUs). The imaging tool is divided into several components, and the back-end handling numerical calculations is generalised in a new framework. A new feature termed compression arbitrarily increases the performance of an already highly efficient GPU-based implementation of the w-projection algorithm. Compression takes advantage of the behaviour of oversampled convolution functions and the baseline trajectories. A CPU-based component prepares data ...

  5. A HIGH PERFORMANCE OPTIMIZATION TECHNIQUE FOR POLE BALANCING PROBLEM

    Directory of Open Access Journals (Sweden)

    Bahadır KARASULU

    2008-02-01

    Full Text Available High performance computing techniques can be used effectively for solution of the complex scientific problems. Pole balancing problem is a basic benchmark tool of robotic field, which is an important field of Artificial Intelligence research areas. In this study, a solution is developed for pole balancing problem using Artificial Neural Network (ANN and high performance computation technique. Algorithm, that basis of the Reinforcement Learning method which is used to find the force of pole's balance, is transfered to parallel environment. In Implementation, C is preferred as programming language and Message Passing Interface (MPI is used for parallel computation technique. Self–Organizing Map (SOM ANN model's neurons (artificial neural nodes and their weights are distributed to six processors of a server computer which equipped with each quad core processor (total 24 processors. In this way, performance values are obtained for different number of artificial neural nodes. Success of method based on results is discussed.

  6. Connection Between X-Ray Emission and Relativistic Jets in the Radio Galaxies 3C 111 and 3C 120

    Science.gov (United States)

    Aller, Margo F.

    2005-01-01

    This work represents a part of a longterm study of the X-ray flux variability in radio galaxies and its relation to flux and structural changes in the associated radio jet. The work described here included: 1) continued study of the emission properties of the FR I radio galaxy 3C 120 known to exhibit a jet/disk connection from our past work; and 2) the commencement of monitoring of a second radio galaxy, the FR I1 object 3C 111 which was selected because of similar radio and X-ray properties to 3C 120, including the presence of Fe K a emission. The association between X-ray dips and new superluminal components, suggesting a picture in which the radio jet is fed by accretion events near the black hole, was identified in 3C 120 using combined RXTE and radio flux monitoring data and bi-monthly to monthly imaging data from the VLBA at 43 GHz. Such data were also obtained for both targets during the period described here. Specific goals were to more broadly investigate the X-ray dip/superluminal connection in 3C 120, thereby determining the epochs of X-ray minima and superluminal ejections more accurately (and hence more precisely determining the distance between the accretion disk and the core of the radio jet), and to determine whether a similar pattern is present in the data for a second radio galaxy. In 3C 111 a different time scale (longer time delays between X-ray dips and superluminal ejections) was expected due to the higher black hole mass implied by its higher radio luminosity: no black hole mass is published for this object but one can be determined from a PDS analysis of the RXTE data. The addition of the second source to the study would identify whether a similar connection was present in other sources and, if found, would provide important information on how time scale (and hence size scale) of accretion disk/jet systems depends on black hole mass. The grant included funding for the reduction and analysis of data obtained during the time period of Rossi

  7. High performance protection circuit for power electronics applications

    Energy Technology Data Exchange (ETDEWEB)

    Tudoran, Cristian D., E-mail: cristian.tudoran@itim-cj.ro; Dădârlat, Dorin N.; Toşa, Nicoleta; Mişan, Ioan [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, PO 5 Box 700, 400293 Cluj-Napoca (Romania)

    2015-12-23

    In this paper we present a high performance protection circuit designed for the power electronics applications where the load currents can increase rapidly and exceed the maximum allowed values, like in the case of high frequency induction heating inverters or high frequency plasma generators. The protection circuit is based on a microcontroller and can be adapted for use on single-phase or three-phase power systems. Its versatility comes from the fact that the circuit can communicate with the protected system, having the role of a “sensor” or it can interrupt the power supply for protection, in this case functioning as an external, independent protection circuit.

  8. High performance protection circuit for power electronics applications

    Science.gov (United States)

    Tudoran, Cristian D.; Dǎdârlat, Dorin N.; Toşa, Nicoleta; Mişan, Ioan

    2015-12-01

    In this paper we present a high performance protection circuit designed for the power electronics applications where the load currents can increase rapidly and exceed the maximum allowed values, like in the case of high frequency induction heating inverters or high frequency plasma generators. The protection circuit is based on a microcontroller and can be adapted for use on single-phase or three-phase power systems. Its versatility comes from the fact that the circuit can communicate with the protected system, having the role of a "sensor" or it can interrupt the power supply for protection, in this case functioning as an external, independent protection circuit.

  9. The architecture of the High Performance Storage System (HPSS)

    Energy Technology Data Exchange (ETDEWEB)

    Teaff, D.; Coyne, B. [IBM Federal, Houston, TX (United States); Watson, D. [Lawrence Livermore National Lab., CA (United States)

    1995-01-01

    The rapid growth in the size of datasets has caused a serious imbalance in I/O and storage system performance and functionality relative to application requirements and the capabilities of other system components. The High Performance Storage System (HPSS) is a scalable, next-generation storage system that will meet the functionality and performance requirements of large-scale scientific and commercial computing environments. Our goal is to improve the performance and capacity of storage systems by two orders of magnitude or more over what is available in the general or mass marketplace today. We are also providing corresponding improvements in architecture and functionality. This paper describes the architecture and functionality of HPSS.

  10. High-performance Scientific Computing using Parallel Computing to Improve Performance Optimization Problems

    Directory of Open Access Journals (Sweden)

    Florica Novăcescu

    2011-10-01

    Full Text Available HPC (High Performance Computing has become essential for the acceleration of innovation and the companies’ assistance in creating new inventions, better models and more reliable products as well as obtaining processes and services at low costs. The information in this paper focuses particularly on: description the field of high performance scientific computing, parallel computing, scientific computing, parallel computers, and trends in the HPC field, presented here reveal important new directions toward the realization of a high performance computational society. The practical part of the work is an example of use of the HPC tool to accelerate solving an electrostatic optimization problem using the Parallel Computing Toolbox that allows solving computational and data-intensive problems using MATLAB and Simulink on multicore and multiprocessor computers.

  11. Memory Benchmarks for SMP-Based High Performance Parallel Computers

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, A B; de Supinski, B; Mueller, F; Mckee, S A

    2001-11-20

    As the speed gap between CPU and main memory continues to grow, memory accesses increasingly dominates the performance of many applications. The problem is particularly acute for symmetric multiprocessor (SMP) systems, where the shared memory may be accessed concurrently by a group of threads running on separate CPUs. Unfortunately, several key issues governing memory system performance in current systems are not well understood. Complex interactions between the levels of the memory hierarchy, buses or switches, DRAM back-ends, system software, and application access patterns can make it difficult to pinpoint bottlenecks and determine appropriate optimizations, and the situation is even more complex for SMP systems. To partially address this problem, we formulated a set of multi-threaded microbenchmarks for characterizing and measuring the performance of the underlying memory system in SMP-based high-performance computers. We report our use of these microbenchmarks on two important SMP-based machines. This paper has four primary contributions. First, we introduce a microbenchmark suite to systematically assess and compare the performance of different levels in SMP memory hierarchies. Second, we present a new tool based on hardware performance monitors to determine a wide array of memory system characteristics, such as cache sizes, quickly and easily; by using this tool, memory performance studies can be targeted to the full spectrum of performance regimes with many fewer data points than is otherwise required. Third, we present experimental results indicating that the performance of applications with large memory footprints remains largely constrained by memory. Fourth, we demonstrate that thread-level parallelism further degrades memory performance, even for the latest SMPs with hardware prefetching and switch-based memory interconnects.

  12. Performance evaluation of high modulus asphalt concrete mixes

    Science.gov (United States)

    Haritonovs, V.; Tihonovs, J.; Zaumanis, M.

    2016-04-01

    Dolomite is one of the most available sedimentary rocks in the territory of Latvia. Dolomite quarries contain about 1000 million tons of this material. However, according to Latvian Road Specifications, this dolomite cannot be used for average and high intensity roads because of its low quality (mainly, LA index). Therefore, mostly imported magmatic rocks (granite, diabase, gabbro, basalt) or imported dolomite are used which makes asphalt expensive. However, practical experience shows that even with these high quality materials roads exhibit rutting, fatigue and thermal cracks. The aim of the research is to develop a high performance asphalt concrete for base and binder courses using only locally available aggregates. In order to achieve resistance against deformations at a high ambient temperature, a hard grade binder was used. Workability, fatigue and thermal cracking resistance, as well as sufficient water resistance is achieved by low porosity (3-5%) and higher binder content compared to traditional asphalt mixtures. The design of the asphalt includes a combination of empirical and performance based tests, which in laboratory circumstances allow simulating traffic and environmental loads. High performance AC 16 base asphalt concrete was created using local dolomite aggregate with polymer modified (PMB 10/40-65) and hard grade (B20/30) bitumen. The mixtures were specified based on fundamental properties in accordance to EN 13108-1 standard.

  13. X-ray Emission from the Radio Jet in 3C 120

    DEFF Research Database (Denmark)

    Harris, D. E.; Hjorth, J.; Sadun, A. C.;

    1999-01-01

    We report the discovery of X-ray emission from a radio knot at a projected distance of 25" from the nucleus of the Seyfert galaxy, 3C 120. The data were obtained with the ROSAT High Resolution Imager (HRI). Optical upper limits for the knot preclude a simple power law extension of the radio spect...

  14. Designing high-performance layered thermoelectric materials through orbital engineering.

    Science.gov (United States)

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K H; Fischer, Karl F F; Zhang, Wenqing; Shi, Xun; Iversen, Bo B

    2016-01-01

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials.

  15. Micromachined high-performance RF passives in CMOS substrate

    Science.gov (United States)

    Li, Xinxin; Ni, Zao; Gu, Lei; Wu, Zhengzheng; Yang, Chen

    2016-11-01

    This review systematically addresses the micromachining technologies used for the fabrication of high-performance radio-frequency (RF) passives that can be integrated into low-cost complementary metal-oxide semiconductor (CMOS)-grade (i.e. low-resistivity) silicon wafers. With the development of various kinds of post-CMOS-compatible microelectromechanical systems (MEMS) processes, 3D structural inductors/transformers, variable capacitors, tunable resonators and band-pass/low-pass filters can be compatibly integrated into active integrated circuits to form monolithic RF system-on-chips. By using MEMS processes, including substrate modifying/suspending and LIGA-like metal electroplating, both the highly lossy substrate effect and the resistive loss can be largely eliminated and depressed, thereby meeting the high-performance requirements of telecommunication applications.

  16. Designing high-Performance layered thermoelectric materials through orbital engineering

    DEFF Research Database (Denmark)

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K. H.

    2016-01-01

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited...... insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach...... naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth...

  17. Designing high-performance layered thermoelectric materials through orbital engineering

    Science.gov (United States)

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K. H.; Fischer, Karl F. F.; Zhang, Wenqing; Shi, Xun; Iversen, Bo B.

    2016-03-01

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials.

  18. Low Cost High Performance Nanostructured Spectrally Selective Coating

    Energy Technology Data Exchange (ETDEWEB)

    JIN, SUNGHO

    2017-04-05

    Sunlight absorbing coating is a key enabling technology to achieve high-temperature high-efficiency concentrating solar power operation. A high-performance solar absorbing material must simultaneously meet all the following three stringent requirements: high thermal efficiency (usually measured by figure of merit), high-temperature durability, and oxidation resistance. The objective of this research is to employ a highly scalable process to fabricate and coat black oxide nanoparticles onto solar absorber surface to achieve ultra-high thermal efficiency. Black oxide nanoparticles have been synthesized using a facile process and coated onto absorber metal surface. The material composition, size distribution and morphology of the nanoparticle are guided by numeric modeling. Optical and thermal properties have been both modeled and measured. High temperature durability has been achieved by using nanocomposites and high temperature annealing. Mechanical durability on thermal cycling have also been investigated and optimized. This technology is promising for commercial applications in next-generation high-temperature concentration solar power (CSP) plants.

  19. High Involvement Management, High Performance Work Systems and Well-being

    OpenAIRE

    Wood, S; Menezes, L. M.

    2011-01-01

    Studies on the impact of high-performance work systems on employees' well-being are emerging but the underlying theory remains weak. This paper attempts to develop theory of the effects on well-being of four dimensions of high-performance work systems: enriched jobs, high involvement management, employee voice, and motivational supports. Hypothesized associations are tested using multilevel models and data from Britain's Workplace Employment Relations Survey of 2004 (WERS2004). Results show t...

  20. Highlighting High Performance: Blackstone Valley Regional Vocational Technical High School; Upton, Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    2006-10-01

    This brochure describes the key high-performance building features of the Blackstone Valley High School. The brochure was paid for by the Massachusetts Technology Collaborative as part of their Green Schools Initiative. High-performance features described are daylighting and energy-efficient lighting, indoor air quality, solar energy, building envelope, heating and cooling systems, and water conservation. Energy cost savings are also discussed.