14 research outputs found

    Symmetries and conservation laws in the Gunther k-symplectic formalism of field theory

    Get PDF
    This paper is devoted to studying symmetries of k-symplectic Hamiltonian and Lagrangian first-order classical field theories. In particular, we define symmetries and Cartan symmetries and study the problem of associating conservation laws to these symmetries, stating and proving Noether's theorem in different situations for the Hamiltonian and Lagrangian cases. We also characterize equivalent Lagrangians, which lead to an introduction of Lagrangian gauge symmetries, as well as analyzing their relation with Cartan symmetries.Comment: 29 page

    Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

    Get PDF
    A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN

    Drons col·laboratius

    Get PDF
    La robòtica col·laborativa és senzillament robots dissenyats per dur a terme treballs de col·laboració amb els humans. Els robots col·laboratius o cobots són cada cop més utilitzats a les indústries. La robòtica col·laborativa és un dels àmbits d'actualitat en aquests moments. Però també és un dels més interessants en més d'un sentit. Com es comuniquen dos drons autònoms que col·laboren per fer una tasca? Com són aquests missatges que s'envien? Que poden fer que no podrien fer sols? Aquestes són algunes de les preguntes que ens volem respondre en aquest projecte. En aquest treball es presenta un disseny i implementació de dos drons terrestres que es comuniquen per col·laborar entre ells per resoldre una tasca.Collaborative robotics is simply robots designed to perform collaborative work with humans. Collaborative robots or cobots are increasingly used in industries. Collaborative robotics is one of the current topics now. But it is also one of the most interesting in more ways than one. How do two autonomous drones that collaborate to perform a task communicate? How are these messages sent? What can they do that they could not do alone? These are some of the questions we want to answer in this project. This work presents a design and implementation of two ground drones that communicate to collaborate with each other to solve a task.La robótica colaborativa es sencillamente robots diseñados para llevar a cabo trabajos de colaboración con los humanos. Los robots colaborativos o cobots son cada vez más utilizados en las industrias. La robótica colaborativa es uno de los ámbitos de actualidad. Pero también es uno de los más interesantes en más de un sentido. ¿Cómo se comunican drones autónomos que colaboran para hacer una tarea? ¿Cómo son estos mensajes que es envían? ¿Qué pueden hacer que no lo podrían hacer solos? Estas son algunas de las preguntas que queremos responder con este proyecto. En este trabajo se presenta un diseño e implementación de dos drones terrestres que se comunican para colaborar entre ellos para resolver una tarea

    Hamiltonian systems on k-cosymplectic manifolds

    Get PDF
    The Hamiltonian framework on symplectic and cosymplectic manifolds is extended in order to consider classical field theories. To do this, the notion of k-cosymplectic manifold is introduced, and a suitable Hamiltonian formalism is developed so that the field equations for scalar and vector Hamiltonian functions are derived. © 1998 American Institute of Physics.This work has been partially supported through grants DGICYT (Spain) (Project No. PB94- 0106) and XUNTA DE GALICIA (Projects No. XUGA13101A94 and No. XUGA13101A96). MdL also acknowledges the support by FAPERJ-Proc. E-26/170.236/96. info:eu-repo/grantAgreement/EC/FP7/Peer Reviewe

    Characteristics, treatment patterns and outcomes of patients presenting with venous thromboembolic events after knee arthroscopy in the RIETE Registry

    No full text
    Knee arthroscopy is the most common orthopedic procedure worldwide. While incidence of post-arthroscopy venous thromboembolic events (VTE) is low, treatment patterns and patient outcomes have not been described. Patients from the "Registro Informatizado Enfermedad TromboEmbolica" who had confirmed post-arthroscopy VTE were compared to patients with provoked, post bone-fracture, and to patients with unprovoked VTE. Baseline characteristics, presenting signs and symptoms, treatment and outcomes including recurrent VTE, bleeds or death were compared. A total of 101 patients with post-arthroscopy VTE and 19,218 patients with unprovoked VTE were identified. Post-arthroscopy patients were younger (49.5 vs. 66 years, P\u2009<\u20090.0001) and had less history of VTE [5.9% vs. 20%, OR 0.26 (0.11-0.59)]. Among patients with isolated DVT, there were fewer proximal DVT in the post-arthroscopy group [40% vs. 86%, OR 0.11 (0.06-0.19)]. Treatment duration was shorter in the post-arthroscopy group (174\u2009\ub1\u2009140 vs. 311\u2009\ub1\u2009340 days, P\u2009<\u20090.0001) and more often with DOAC [OR 3.67 (1.95-6.89)]. Recurrent VTE occurred in 6.18 (1.96-14.9) and 11.9 (11.0-12.8) per 100 patient years [HR 0.52 (0.16-1.26)] after treatment in the post-arthroscopy and unprovoked groups, respectively. Recurrent VTE occurred in 5.17 (1.31-14.1) per 100 patient years in a separate post bone-fracture group (n\u2009=\u2009147), also not statistically different than the post-arthroscopy recurrence rate. After anticoagulation cessation, some patients post-knee arthroscopy develop VTE. While our small sample size precludes drawing firm conclusions, this signal should warrant further research into the optimal treatment duration for these patients, as some patients may be at increased risk for long-term recurrence

    ATLAS

    No full text
    % ATLAS \\ \\ ATLAS is a general-purpose experiment for recording proton-proton collisions at LHC. The ATLAS collaboration consists of 144 participating institutions (June 1998) with more than 1750~physicists and engineers (700 from non-Member States). The detector design has been optimized to cover the largest possible range of LHC physics: searches for Higgs bosons and alternative schemes for the spontaneous symmetry-breaking mechanism; searches for supersymmetric particles, new gauge bosons, leptoquarks, and quark and lepton compositeness indicating extensions to the Standard Model and new physics beyond it; studies of the origin of CP violation via high-precision measurements of CP-violating B-decays; high-precision measurements of the third quark family such as the top-quark mass and decay properties, rare decays of B-hadrons, spectroscopy of rare B-hadrons, and Bs0 B ^0 _{s} -mixing. \\ \\The ATLAS dectector, shown in the Figure includes an inner tracking detector inside a 2~T~solenoid providing an axial field, electromagnetic and hadronic calorimeters outside the solenoid and in the forward regions, and barrel and end-cap air-core-toroid muon spectrometers. The precision measurements for photons, electrons, muons and hadrons, and identification of photons, electrons, muons, τ\tau-leptons and b-quark jets are performed over η| \eta | < 2.5. The complete hadronic energy measurement extends over η| \eta | < 4.7. \\ \\The inner tracking detector consists of straw drift tubes interleaved with transition radiators for robust pattern recognition and electron identification, and several layers of semiconductor strip and pixel detectors providing high-precision space points. \\ \\The e.m. calorimeter is a lead-Liquid Argon sampling calorimeter with an integrated preshower detector and a presampler layer immediately behind the cryostat wall for energy recovery. The end-cap hadronic calorimeters also use Liquid Argon technology, with copper absorber plates. The end-cap cryostats house the e.m., hadronic and forward calorimeters (tungsten-Liquid Argon sampling). The barrel hadronic calorimeter is an iron-scintillating tile sampling calorimeter with longitudinal tile geometry. \\ \\Air-core toroids are used for the muon spectrometer. Eight superconducting coils with warm voussoirs are used in the barrel region complemented with superconducting end-cap toroids in the forward regions. The toroids will be instrumented with Monitored Drift Tubes (Cathode Strip Chambers at large rapidity where there are high radiation levels). The muon trigger and second coordinate measurement for muon tracks are provide
    corecore