262 research outputs found

    Advanced turboprop multidisciplinary design and optimization within agile project

    Get PDF
    The present paper deals with the design, analysis and optimization of a 90 passengers turboprop aircraft with a design range of 1200 nautical miles and a cruise Mach number equal to 0.56. The prescribed aircraft is one of the use cases of the AGILE European project, aiming to provide a 3rd generation of multidisciplinary design and optimization chain, following the collaborative and remote aircraft design paradigm, through an heterogenous team of experts. The multidisciplinary aircraft design analysis is set-up involving tools provided by AGILE partners distributed worldwide and run locally from partners side. A complete design of experiment, focused on wing planform variables, is performed to build response surfaces suitable for optimization purposes. The goal of the optimization is the direct operating cost, subject to wing design variables and top-level aircraft requirements

    Methodological enhancements in MDO process investigated in the AGILE European project

    Get PDF
    This paper presents methodological investigations performed in research activities in the field of MDO in overall aircraft design in the ongoing EU funded research project AGILE. AGILE is developing the next generation of aircraft Multidisciplinary Design and Optimization processes, which target significant reductions in aircraft development costs and time to market, leading to cheaper and greener aircraft solutions. The paper introduces the AGILE project structure and describes the achievements of the 1st year (Design Campaign 1) leading to a reference distributed MDO system. A focus is then made on the different novel optimization techniques studied during the 2nd year, all willing to ease the optimization of complex work flows, characterized by high degree of discipline interdependencies, high number of design variables in the context of multi-level and multi-partner collaborative engineering projects. Then the implementation of these methods in the enhanced MDO framework is discussed

    A search for anomalously heavy isotopes of low Z nuclei

    Full text link
    We present preliminary results of a search for anomalously heavy isotopes of certain light elements using an electrostatic charged particle spectrometer in conjunction with the MP tandem accelerator facility at the Nuclear Structure Research Laboratory of the University of Rochester. New limits for the existence of anomalous, heavy isotopes (100–10,000 amu) in ordinary, terrestrial Li, Be, B and F samples and enriched H2, C13, and O18 samples are reported.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87394/2/1143_1.pd

    Docker experience at INFN-Pisa Grid Data Center

    Get PDF
    Clouds and virtualization offer typical answers to the needs of large-scale computing centers to satisfy diverse sets of user communities in terms of architecture, OS, etc. On the other hand, solutions like Docker seems to emerge as a way to rely on Linux kernel capabilities to package only the applications and the development environment needed by the users, thus solving several resource management issues related to cloud-like solutions. In this paper, we present an exploratory (though well advanced) test done at a major Italian Tier2, at INFN-Pisa, where a considerable fraction of the resources and services has been moved to Docker. The results obtained are definitely encouraging, and Pisa is transitioning all of its Worker Nodes and services to Docker containers. Work is currently being expanded into the preparation of suitable images for a completely virtualized Tier2, with no dependency on local configurations

    A first measurement of the interaction cross section of the tau neutrino

    Get PDF
    The DONuT experiment collected data in 1997 and published first results in 2000 based on four observed Μτ\nu_\tau charged-current (CC) interactions. The final analysis of the data collected in the experiment is presented in this paper, based on 3.6×10173.6 \times 10^{17} protons on target using the 800 GeV Tevatron beam at Fermilab. The number of observed Μτ\nu_\tau CC interactions is 9, from a total of 578 observed neutrino interactions. We calculated the energy-independent part of the tau-neutrino CC cross section (Îœ+Μˉ\nu + \bar \nu), relative to the well-known Îœe\nu_e and ΜΌ\nu_\mu cross sections. The ratio σ(Μτ)\sigma(\nu_\tau)/σ(Îœe,ÎŒ)\sigma(\nu_{e,\mu}) was found to be 1.37±0.35±0.771.37\pm0.35\pm0.77. The Μτ\nu_\tau CC cross section was found to be 0.72±0.24±0.36×10−380.72 \pm 0.24\pm0.36 \times 10^{-38} cm2GeV−1^{2}\rm{GeV}^{-1}. Both results are in agreement the Standard Model.Comment: 37 pages, 15 figure

    A precise measurement of the non‐leptonic weak decay parameters α and ϕ in the spin 3/2 decay ω−→Λ0+K−

    Full text link
    Experiment E800 at Fermilab using the E800 spectrometer has made a precise measurement of the non‐leptonic weak decay parameters for the spin 3/2 decay, Ω−→Δ°+K−. The paratmeters determined are αΎαΩ=0.0126±0.0042, αΩ=0.0196±0.0066, and ϕπ=−3.4°±10.3°. This measurement of αΩ is nearly four times more precise than the previous world average value of −0.026±0.026 and shows this parameter to be inconsistent with zero. Also, E800 has made the first measurement of ϕΩ. (AIP) © 1995 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87479/2/692_1.pd

    A precision measurement of the Ω− magnetic moment

    Full text link
    The structure of baryons can be probed at long range by measuring their magnetic moments. The particulary simple valence quark structure (three strange quarks with their spins aligned) of the Ω− should make a precise measurments its magnetic moment a useful test of models of baryon structure. The only previous measurement of the Ω− magnetic moment to a precision of 10%, could not clearly differentiate between these models. © 1995 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87480/2/478_1.pd

    Enhancing optimization capabilities using the AGILE collaborative MDO framework with application to wing and nacelle design

    Get PDF
    This paper presents methodological investigations performed in research activities in the field of Multi-disciplinary Design and Optimization (MDO) for overall aircraft design in the EU funded research project AGILE (2015–2018). In the AGILE project a team of 19 industrial, research and academic partners from Europe, Canada and Russia are working together to develop the next generation of MDO environment that targets significant reductions in aircraft development costs and time to market, leading to cheaper and greener aircraft. The paper introduces the AGILE project structure and describes the achievements of the 1st year that led to a reference distributed MDO system. A focus is then made on different novel optimization techniques studied during the 2nd year, all aiming at easing the optimization of complex workflows that are characterized by a high number of discipline interdependencies and a large number of design variables in the context of multi-level processes and multi-partner collaborative engineering projects. Three optimization strategies are introduced and validated for a conventional aircraft. First, a multi-objective technique based on Nash Games and Genetic Algorithm is used on a wing design problem. Then a zoom is made on the nacelle design where a surrogate-based optimizer is used to solve a mono-objective problem. Finally a robust approach is adopted to study the effects of uncertainty in parameters on the nacelle design process. These new capabilities have been integrated in the AGILE collaborative framework that in the future will be used to study and optimize novel unconventional aircraft configurations

    Localization of a continuous CO2 leak from an isotropic flat-surface structure using acoustic emission detection and near-field beamforming techniques

    Get PDF
    Seal capacity is of great importance for the safety operation of pressurized vessels. It is crucial to locate the leak hole timely and accurately for reasons of safety and maintenance. This paper presents the principle and application of a linear acoustic emission sensor array and a near-field beamforming technique to identify the location of a continuous CO2 leak from an isotropic flat-surface structure on a pressurized vessel in the Carbon Capture and Storage system. Acoustic signals generated by the leak hole are collected using a linear high-frequency sensor array. Time-frequency analysis and a narrow-band filtering technique are deployed to extract effective information about the leak. The impacts of various factors on the performance of the localization technique are simulated, compared and discussed, including the number of sensors, distance between the leak hole and sensor array and spacing between adjacent sensors. Experiments were carried out on a laboratory-scale test rig to assess the effectiveness and operability of the proposed method. The results obtained suggest that the proposed method is capable of providing accurate and reliable localization of a continuous CO2 leak
    • 

    corecore