12,196 research outputs found

    The impact of in-season national team soccer play on injury and player availability in a professional club

    Get PDF
    This study investigated the impact of in-season national team duty on injury rates and player availability in a professional soccer club. Time-loss injuries and exposure time during club and national team duties were recorded prospectively over 5 seasons (2009–2014). A time-loss injury was sustained by 37.7% of squad members participating in national duty, all injuries occurring in match-play. The incidence (per 1000 h exposure) for national team player match-play injuries did not differ (P = 0.608) to that for all players in club competitions: 48.0 (95% CI 20.9–75.5) vs. 41.9 (95% CI 36.5–47.4), incidence rate ratio = 1.2 (CI: 0.8–2.4). The majority (58%) of national team injuries resulted in a layoff ≤1 week. Of all working days lost to injury generally, 5.2% were lost through injury on national duty. Injury incidence in the week following national duty was comparable (P = 0.818) in players participating or not: 7.8 (95% CI 3.6–12.0) vs. 7.1 (95% CI: 4.6–9.6), incidence rate ratio = 1.1 (CI: 0.7–2.7). While approximately 40% of participating players incurred a time-loss injury on national duty, no training injuries were sustained and injuries made up a negligible part of overall club working days lost to injury. Following duty, players had a similar injury risk to peers without national obligations

    A MLM-Based Order Entry System: The Use of Knowledge in a Traditional HIS Application

    Get PDF
    Conference PaperBiomedical Informatic

    Burial Recording Mines: a valid technique to study bedform migration and storm impact above the sea-floor

    Get PDF
    Initially, Burial Recording Mines (BRMs) were used to understand the sea mine burial. It was a technique predominantly related to military purpose. The first experiment was made 1974. Now a day, it is used as a valid tool for marine science. This methodology gives the rare opportunity to observe and analyze the processes acting on the seafloor directly, making the estimation closer to the reality. During MARIDIV, we present the results of 3 months experiment using burial recording mines. The experiment was performed between September 2008 and January 2009. The Wandelaar region on the Belgian Continental Shelf was chosen as suitable test area. 10,000 measurements of the sediment height around the cylindrical object were recorded, each one of those every 15 minutes. The dataset collected, together with sediment characterization and hydrological and meteorological information, allowed the understanding of the bedform migration. During the experiment, 2 storms passed the test area, in October and November 2008. Using Burial Recording Mines gave the rare opportunity to observe and analyze the storm impact directly on the sea-floor. Processes during and after the second storm will be revealed

    Storms: a challenge of knowledge [POSTER]

    Get PDF

    Kinetics study and modelling of steam methane reforming process over a NiO/Al2O3 catalyst in an adiabatic packed bed reactor

    No full text
    Kinetic rate data for steam methane reforming (SMR) coupled with water gas shift (WGS) over an 18 wt. % NiO/α-Al2O3 catalyst are presented in the temperature range of 300-700 °C at 1 bar. The experiments were performed in a plug flow reactor under the conditions of diffusion limitations and away from the equilibrium conditions. The kinetic model was implemented in a one-dimensional heterogeneous mathematical model of catalytic packed bed reactor, developed on gPROMS model builder 4.1.0®. The mathematical model of SMR process was simulated, and the model was validated by comparing the results with the experimental values. The simulation results were in excellent agreement with the experimental results. The effect of various operating parameters such as temperature, pressure and steam to carbon ratio on fuel and water conversion (%), H2 yield (wt. % of CH4) and H2 purity was modelled and compared with the equilibrium values

    Chemical equilibrium analysis of hydrogen production from shale gas using sorption enhanced chemical looping steam reforming

    Get PDF
    Detailed chemical equilibrium analysis based on minimisation of Gibbs Energy is conducted to illustrate the benefits of integrating sorption enhancement (SE) and chemical looping (CL) together with the conventional catalytic steam reforming (C-SR) process for hydrogen production from a typical shale gas feedstock. CaO(S) was chosen as the CO2 sorbent and Ni/NiO is the oxygen transfer material (OTM) doubling as steam reforming catalyst. Up to 49 % and 52 % rise in H2 yield and purity respectively were achieved with SE-CLSR with a lower enthalpy change compared to C-SR at S:C 3 and 800 K. A minimum energy of 159 kJ was required to produce 1 mole of H2 at S:C 3 and 800 K in C-SR process, this significantly dropped to 34 kJ/mol of produced H2 in the CaO(S) /NiO system at same operating condition without regeneration of the sorbent, when the energy of regenerating the sorbent at 1170 K was included, the enthalpy rose to 92 kJ/mol H2, i.e., significantly lower than the Ca-free system. The presence of inert bed materials in the reactor bed such as catalyst support or degraded CO2 sorbent introduced a very substantial heating burden to bring these materials from reforming temperature to sorbent regeneration temperature or to Ni oxidation temperature. The choice of S:C ratio in conditions of excess steam represents a compromise between the higher H2 yield and purity and lower risk of coking, balanced by the increased enthalpy cost of raising excess steam

    Effect of hydrocarbon fractions, Nâ‚‚ and COâ‚‚ in feed gas on hydrogen production using sorption enhanced steam reforming: Thermodynamic analysis

    Get PDF
    Hâ‚‚ yield and purity from sorption enhanced steam reforming (SE-SR) are determined by temperature, S:C ratio in use, and feed gas composition in hydrocarbons, Nâ‚‚ and COâ‚‚. Gases with high hydrocarbons composition had the highest Hâ‚‚ yield and purity. The magnitude of sorption enhancement effects compared to conventional steam reforming (C-SR), i.e. increases in Hâ‚‚ yield and purity, and drop in CHâ‚„ yield were remarkably insensitive to alkane (C1-C3) and COâ‚‚ content (0.1-10 vol%), with only Nâ‚‚ content (0.4-70 vol%) having a minor effect. Although the presence of inert (Nâ‚‚) decreases the partial pressure of the reactants which is beneficial in steam reforming, high inert contents increase the energetic cost of operating the reforming plants. The aim of the study is to investigate and demonstrate the effect of actual shale gas composition in the SE-SR process, with varied hydrocarbon fractions, COâ‚‚ and Nâ‚‚ in the feedstock

    Search for anisotropic effects of hcp solid helium on optical lines of cesium impurities

    Full text link
    The anisotropic effect of a hcp 4He solid matrix on cesium atoms has been proposed as a tool to reveal the parity violating anapole moment of its nucleus. It should also result in splitting the D2 optical excitation line in a way depending on the light polarization. An experimental investigation has been set up using oriented hcp helium crystals in which cesium metal grains are embedded. Atoms are created by laser sputtering from this grains. Optical absorption spectra of the D2 line have been recorded in the temperature range of 1.0 to 1.4 K at liquid/solid coexistence pressure by monitoring the fluorescence on the D2 line at 950 nm. No significant effect of the light polarization has been found, suggesting a statistically isotropic disordered solid environment for the cesium atoms.Comment: The original publication will be available at http://www.springerlink.co

    Modelling of H2 production via sorption enhanced steam methane reforming at reduced pressures for small scale applications

    Get PDF
    The production of H2 via sorption enhanced steam reforming (SE-SMR) of CH4 using 18 wt. % Ni/ Al2O3 catalyst and CaO as a CO2-sorbent was simulated for an adiabatic packed bed reactor at the reduced pressures typical of small and medium scale gas producers and H2 end users. To investigate the behaviour of reactor model along the axial direction, the mass, energy and momentum balance equations were incorporated in the gPROMS modelbuilder®. The effect of operating conditions such as temperature, pressure, steam to carbon ration (S/C) and gas mass flow velocity (Gs) was studied under the low-pressure conditions (2 – 7 bar). Independent equilibrium based software, chemical equilibrium with application (CEA), was used to compare the simulation results with the equilibrium data. A good agreement was obtained in terms of CH4 conversion, H2 yield (wt. % of CH4 feed), purity of H2 and CO2 capture for the lowest (Gs) representing conditions close to equilibrium under a range of operating temperatures pressures, feed steam to carbon ratio. At Gs of 3.5 kg m-2s-1, 3 bar, 923 K and S/C of 3, CH4 conversion and H2 purity were up to 89% and 86% respectively compared to 44% and 63% in the conventional reforming process

    Commissioning of the CMS Cryogenic System After Final Installation in the Underground Cavern

    Get PDF
    After having served for the surface tests of the Compact Muon Solenoid (CMS) magnet, the cold box and ancillaries of the CMS helium refrigerator have been dismantled, moved and re-installed in the USC55 cavern in 2007. The full re-commissioning in the cavern has been followed by several tests of the refrigerator to confirm its nominal performance before it was used for the magnet and detector tests in 2008. During these tests the safety modes of the refrigeration system have been tested and improved. After a nine-year project both, the magnet and the refrigeration system are now ready for the CMS operation
    • …
    corecore