26 research outputs found

    Control of a multivariable web winding system

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    To guarantee a good productivity and a better quality of the industrial systems, it is necessary to know the evolution of its various parameters but also its operation mode. The main goal of this work is to carry out a study to improve a flatness control in a reversing cold rolling mill, precisely the web winding system part. We designate by a winding process any system applying the cycles of unwinding, transport, treatment and winding to various flat products. This system knows several constraints such as the thermal effects caused by the frictions, and the mechanical effects provoked by metal elongation, that generates dysfunctions due to the influence of the process conditions. For this installations type, the various automatisms functions, often very advanced, are realized in modular systems with distributed architecture. Our main goal is to obtain a precise thickness, with the best possible regularity. With this intention, we are preceded to the modelling and the control of the nonlinear dynamic behaviour of a web winding process

    Modeling and Simulation of Radiative Compressible Flows in Aerodynamic Heating Arc-Jet Facility

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    Numerical simulations of an arc heated flow inside NASA's 20 [MW] Aerodynamics heating facility (AHF) are performed in order to investigate the three-dimensional swirling flow and the current distribution inside the wind tunnel. The plasma is considered in Local Thermodynamics Equilibrium(LTE) and is composed of Air-Argon gas mixture. The governing equations are the Navier-Stokes equations that include source terms corresponding to Joule heating and radiative cooling. The former is obtained by solving an electric potential equation, while the latter is calculated using an innovative massively parallel ray-tracing algorithm. The fully coupled system is closed by the thermodynamics relations and transport properties which are obtained from Chapman-Enskog method. A novel strategy was developed in order to enable the flow solver and the radiation calculation to be preformed independently and simultaneously using a different number of processors. Drastic reduction in the computational cost was achieved using this strategy. Details on the numerical methods used for space discretization, time integration and ray-tracing algorithm will be presented. The effect of the radiative cooling on the dynamics of the flow will be investigated. The complete set of equations were implemented within the COOLFluiD Framework. Fig. 1 shows the geometry of the Anode and part of the constrictor of the Aerodynamics heating facility (AHF). Fig. 2 shows the velocity field distribution along (x-y) plane and the streamline in (z-y) plane

    Informatics progress of the Global Burden of Animal Diseases programme towards data for One Health

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    The Global Burden of Animal Diseases (GBADs) programme will provide data-driven evidence that policy-makers can use to evaluate options, inform decisions, and measure the success of animal health and welfare interventions. The GBADs' Informatics team is developing a transparent process for identifying, analysing, visualising and sharing data to calculate livestock disease burdens and drive models and dashboards. These data can be combined with data on other global burdens (human health, crop loss, foodborne diseases) to provide a comprehensive range of information on One Health, required to address such issues as antimicrobial resistance and climate change. The programme began by gathering open data from international organisations (which are undergoing their own digital transformations). Efforts to achieve an accurate estimate of livestock numbers revealed problems in finding, accessing and reconciling data from different sources over time. Ontologies and graph databases are being developed to bridge data silos and improve the findability and interoperability of data. Dashboards, data stories, a documentation website and a Data Governance Handbook explain GBADs data, now available through an application programming interface. Sharing data quality assessments builds trust in such data, encouraging their application to livestock and One Health issues. Animal welfare data present a particular challenge, as much of this information is held privately and discussions continue regarding which data are the most relevant. Accurate livestock numbers are an essential input for calculating biomass, which subsequently feeds into calculations of antimicrobial use and climate change. The GBADs data are also essential to at least eight of the United Nations Sustainable Development Goals

    Prevalencia y factores asociados a calculo dental y enfermedades periodontal en los perros del distrito de Huánuco

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    TesisSe estudiaron 120 caninos para determinar la prevalencia de cálculo y enfermedad periodontal (Gingivitis y Periodontitis) en la ciudad de Huánuco. A los 120 canes se les realizo un examen clínico estomatognático con la finalidad de diagnosticar la presencia de cálculos dentales, gingivitis y periodontitis y determinar la relación según la edad a la que se agrupo de 1-3 años, 4-7 años y de 8-10 años, tipo de alimentación (balanceado, casero y mixto) y estructura anatómica del cráneo (dolicocefalicos, mesocefalicos y braquiocefálico), mediante observación directa y la anamnesis Encontrando la prevalencia de cálculo dental de 60.80%, gingivitis 24.13% y de periodontitis 60.70% Al realizar un análisis comparativo entre la gingivitis y las variables edad existe relación estadística pero no se encontró relación entre gingivitis con la estructura anatómica y el tipo de alimento lo que significa que la dieta y el tipo de cráneo no influye sobre la enfermedad gingival, pero sí la periodontitis tiene relación con la edad, tipo de alimentación y tipo de cráneo
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