884 research outputs found

    Exchange Diffusion Effect and Euryhalinity in Teleosts

    Full text link

    3D arrayed microwave tomographic system for medical imaging

    Get PDF
    In this paper, a combined tomographic imaging system comprising the rotation of a multiplexed linear antenna array around the object under test is designed. With this system a cylindrical sampling is obtained, allowing to scan realistic phantoms without important restrictions on its shape. This, combined with the non-application specific 3D ultrawide band (UWB) Hybrid Focusing reconstruction algorithm, allows to use this system in a wide range of applications. The design of a multiplexed array of UWB antennas for medical applications entails significant challenges including a large impedance bandwidth, small size and low coupling between elements, which will be treated in this paper.Peer ReviewedPostprint (published version

    ElaboraciĂł d'una guia sobre aprenentatge cooperatiu a la Universitat de Girona

    Get PDF
    L’any 2009, l’Institut de CiĂšncies de l’EducaciĂł Josep Pallach de la Universitat de Girona va impulsar la creaciĂł de diverses Xarxes d’InnovaciĂł Docent (XID). Aquestes xarxes agrupen professors de disciplines diverses que volen compartir experiĂšncies relatives a la millora docent. Una d’aquestes xarxes Ă©s la relativa a l’Aprenentatge Cooperatiu (XIDAC). Es compon de vuit professors que utilitzen aquest mĂštode d’aprenentatge a la seva docĂšncia. Un dels seus objectius Ă©s produir una guia o petit manual sobre aprenentatge cooperatiu (AC) a la UdG. Es tracta d’orientar els professors que vulguin posar- lo en prĂ ctica, o que ja ho estiguin fent i necessitin un material de suport. A la present comunicaciĂł es descriu el procĂ©s d’elaboraciĂł d’aquesta guia. En primer lloc, s’exposen caracterĂ­stiques de la UdG que poden determinarne en algun sentit el perfil i continguts. DesprĂ©s, es resumeixen els resultats d’entrevistes amb professors que apliquen l’AC tot i no pertĂ nyer a la Xarxa. A continuaciĂł, es resumeixen els resultats d’una enquesta elaborada al professorat de la UdG (actualment estĂ  en fase de resposta). Amb posterioritat, es fa una presentaciĂł general de la futura guia i es descriu breument un exemple de fitxa d’activitat d’AC. Finalment, es fa referĂšncia al procĂ©s de debat obert de part d’aquests continguts a travĂ©s d’una pĂ gina web, per tal de recollir punts de vista externs i millorar la proposta.Peer Reviewe

    Review Paper on Road Vehicle Vibration Simulation for Packaging Testing Purposes

    Get PDF
    Inefficient packaging constitutes a global problem that costs hundreds of billions of dollars, not to mention the additional environmental impacts. An insufficient level of packaging increases the occurrence of product damage, while an excessive level increases the packages' weight and volume, thereby increasing distribution cost. This problem is well known, and for many years, engineers have tried to optimize packaging to protect products from transport hazards for minimum cost. Road vehicle shocks and vibrations, which is one of the primary causes of damage, need to be accurately simulated to achieve optimized product protection. Over the past 50 years, road vehicle vibration physical simulation has progressed significantly from simple mechanical machines to sophisticated computer-driven shaking tables. There now exists a broad variety of different methods used for transport simulation. Each of them addresses different particularities of the road vehicle vibration. Because of the nature of the road and vehicles, different sources and processes are present in the vibration affecting freight. Those processes can be simplified as the vibration generated by the general road surface unevenness, road surface aberrations (cracks, bumps, potholes, etc.) and the vehicle drivetrain system (wheels, drivetrain, engine, etc.). A review of the transport vibration simulation methods is required to identify and critically evaluate the recent developments. This review begins with an overview of the standardized methods followed by the more advanced developments that focus on the different random processes of vehicle vibration by simulating non-Gaussian, non-stationary, transient and harmonic signals. As no ideal method exists yet, the review presented in this paper is a guide for further research and development on the topic

    Observation of an Excited Bc+ State

    Get PDF
    Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+Îł decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date

    Study of charmonium production in b -hadron decays and first evidence for the decay Bs0

    Get PDF
    Using decays to φ-meson pairs, the inclusive production of charmonium states in b-hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0 fb−1, collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. Denoting byBC ≡ B(b → C X) × B(C → φφ) the inclusive branching fraction of a b hadron to a charmonium state C that decays into a pair of φ mesons, ratios RC1C2 ≡ BC1 /BC2 are determined as Rχc0ηc(1S) = 0.147 ± 0.023 ± 0.011, Rχc1ηc(1S) =0.073 ± 0.016 ± 0.006, Rχc2ηc(1S) = 0.081 ± 0.013 ± 0.005,Rχc1 χc0 = 0.50 ± 0.11 ± 0.01, Rχc2 χc0 = 0.56 ± 0.10 ± 0.01and Rηc(2S)ηc(1S) = 0.040 ± 0.011 ± 0.004. Here and below the first uncertainties are statistical and the second systematic.Upper limits at 90% confidence level for the inclusive production of X(3872), X(3915) and χc2(2P) states are obtained as RX(3872)χc1 < 0.34, RX(3915)χc0 < 0.12 andRχc2(2P)χc2 < 0.16. Differential cross-sections as a function of transverse momentum are measured for the ηc(1S) andχc states. The branching fraction of the decay B0s → φφφ is measured for the first time, B(B0s → φφφ) = (2.15±0.54±0.28±0.21B)×10−6. Here the third uncertainty is due to the branching fraction of the decay B0s → φφ, which is used for normalization. No evidence for intermediate resonances is seen. A preferentially transverse φ polarization is observed.The measurements allow the determination of the ratio of the branching fractions for the ηc(1S) decays to φφ and p p asB(ηc(1S)→ φφ)/B(ηc(1S)→ p p) = 1.79 ± 0.14 ± 0.32
    • 

    corecore