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It’s not all in your feet: Improving penalty kick performance with humanavatar interaction and machine learning

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The Innovation 2024年第2期5卷 115-121页

作者： Jean-Luc Bloechle Julien Audiffren Thibaut Le Naour Andrea Alli Dylan simoni Gabriel Wüthrich Jean-pierre Bresciani Control and perception Laboratory University of FribourgBd Perolles 901700 FribourgSwitzerland Motion-up Le PrismePlace Albert Einstein56000 VannesFrance FC Basel 1893 Birsstrasse 320A4002 BaselSwitzerland

penalty kicks are increasingly decisive in major international football ***,over 30%of shootout kicks are *** outcome of the kick often relies on the ability of the penalty taker to exploit anticipatory movements of the goalkeeper to redirect the kick toward the open side of the ***,this ability is difficult to train using classical *** used an augmented reality simulator displaying an holographic goalkeeper to test and train penalty kick performance with 13 young elite *** learning algorithms were used to optimize the learning rate by maintaining an optimal level of training *** training sessions of 20 kicks reduced the redirection threshold by 120 ms,which constituted a 28%reduction with respect to the baseline ***,redirection threshold reduction was observed for all trained players,and all things being equal,it corresponded to an estimated 35%improvement of the success rate.

关键词： kick penalty learning

Gate-controlled supercurrent effect in dry-etched Dayem bridges of non-centrosymmetric niobium rhenium

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Nano Research 2024年第7期17卷 6575-6581页

作者： Jennifer Koch Carla Cirillo Sebastiano Battisti Leon Ruf Zahra Makhdoumi Kakhaki Alessandro paghi Armen Gulian Serafim Teknowijoyo Giorgio De simoni Francesco Giazotto Carmine Attanasio Elke Scheer Angelo Di Bernardo Department of physics University of KonstanzUniversitätsstraße 1078464 KonstanzGermany CNR-Spin c/o Universitàdegli Studi di Salernovia Giovanni Paolo II 13284084 Fisciano(SA)Italy NEST Istituto Nanoscienze-CNR and Scuola Normale SuperiorePiazza San Silvestro 1256127 PisaItaly Dipartimento di Fisica“E.R.Caianiello” Universitàdegli Studi di SalernoVia Giovanni Paolo II 13284084 Fisciano(SA)Italy Advanced physics Laboratory Institute for Quantum StudiesChapman UniversityBurtonsvilleMD 20866USA

The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction,named as gate-controlled supercurrent(GCS),has raised great interest for fundamental and technological *** gain a deeper understanding of this effect and develop superconducting technologies based on it,the material and physical parameters crucial for the GCS effect must be ***-down fabrication protocols should also be optimized to increase device scalability,although studies suggest that top-down fabricated devices are more resilient to show a ***,we investigate gated superconducting nanobridges made with a top-down fabrication process from thin films of the noncentrosymmetric superconductor niobium rhenium with varying ratios of the constituents(NbRe).Unlike other devices previously reported and made with a top-down approach,our NbRe devices systematically exhibit a GCS effect when they were fabricated from NbRe thin films with small grain size and etched in specific *** observations pave the way for the realization of top-down-made GCS devices with high *** results also imply that physical parameters like structural disorder and surface physical properties of the nanobridges,which can be in turn modified by the fabrication process,are crucial for a GCS observation,providing therefore also important insights into the physics underlying the GCS effect.

关键词： superconductivity non-centrosymmetric superconductors superconducting devices gated devices gate-controlled supercurrent top-down fabrication

比较全身MRI(WB-MRI)与中轴骨MRI(AS-MRI)对前列腺癌(pCa)骨转移瘤的检出与计量

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国际医学放射学杂志 2011年第1期34卷 101-102页

作者： F.E.Lecouvet M.Simon B.Tombal J.Jamart B.C.Vande Berg p.simoni 许亮 Department of Radiology and Medical Imaging Université Catholique de LouvainCliniques Universitaires St Luc

目的比较全身MRI(WB-MRI)和中轴骨MRI(AS-MRI)对前列腺癌(pCa)骨转移瘤的检出与计量。方法对60例存在转移瘤高风险的pCa病人行WB-MRI和AS-

关键词：前列腺癌骨 MRI 转移瘤

Experimental Investigation of Flow Instabilities in a Laminar Separation Bubble

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Journal of Thermal Science 2014年第3期23卷 203-214页

作者： simoni D. Ubaldi M. Zunino p. DIME-Università di GenovaVia Montallegro 1 I-16145 Genova Italy DIME-Università di Genova Via Montallegro 1 I-16145 Genova Italy

The present paper reports the results of a detailed experimental study aimed at investigating the dynamics of a laminar separation bubble, from the origin of separation up to the breakdown to turbulence of the large scale co- herent structures generated as a consequence of the Kelvin-Helmholtz instability process. Measurements have been performed along a fiat plate installed within a double contoured test section, designed to produce an adverse pressure gradient typical of Ultra-High-Lift turbine blade profiles, which induces the formation of a laminar separation bubble at low Reynolds number condition. Measurements have been carried out by means of comple- mentary techniques： hot-wire （HW） anemometry, Laser Doppler Velocirnetry （LDV） and particle Image Veloci- metry （pIV）. The high accuracy 2-dimensional LDV results allow investigating reverse flow magnitude and both Reynolds normal and shear stress distributions along the separated flow region, while the high frequency response of the HW anemometer allows analyzing the amplification process of flow oscillations induced by instability mechanisms. pIV results complement the flow field analysis providing information on the generation and evolu- tion of the large scale coherent structures shed as a consequence of the separated shear layer roll-up, through in- stantaneous velocity vector maps. The simultaneous analysis of the data obtained by means of the different meas- uring techniques allows an in depth view of the instability mechanisms involved in the transition/reattachrnent processes of the separated shear layer.

关键词： Ultra-High-Lift turbine profiles separated flow transition mode streaks Kelvin-Helmholtz instabil- ity linear stability theory

Experimental Investigation of Separation and Transition processes on a High-Lift Low-pressure Turbine profile Under Steady and Unsteady Inflow at Low Reynolds Number

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Journal of Thermal Science 2010年第1期19卷 26-33页

作者： Satta F simoni D Ubaldi M Zunino p Bertini F DIMSET-Università di Genova Via Montallegro 1I-16145 GenovaItaly Avio R&D V.I Maggio99 I-10040 Rivalta(TO)-Italy

The effects induced by the presence of incoming wakes on the boundary layer developing over a high-lift low-pressure turbine profile have been investigated in a linear cascade at *** tested Reynolds number is 70000,typical of the cruise operating *** results of the investigations performed under steady and unsteady inflow conditions are *** unsteady investigations have been performed at the reduced frequency of f+=0.62,representative of the real engine operating *** aerodynamic loadings as well as boundary layer velocity profiles have been measured to survey the separation and transition *** analysis has been also performed to better understand the phenomena associated with the transition process under steady *** the unsteady case,a phase-locked ensemble averaging technique has been employed to reconstruct the time-resolved boundary layer velocity distributions from the hot-wire instantaneous signal *** ensemble-averaging technique allowed a detailed analysis of the effects induced by incoming wakes-boundary layer interaction in separation ***-resolved results are presented in terms of mean velocity and unresolved unsteadiness time-space plots.

关键词： boundary layer separation boundary layer transition wake-boundary layer interaction high-liftprofile low-pressure turbine

Free-stream Turbulence Effects on the Boundary Layer of a High-lift Low-pressure-Turbine Blade

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Journal of Thermal Science 2016年第3期25卷 195-206页

作者： simoni D. Ubaldi M. Zunino p. Ampellio E. DIME-Universita di Genova Via MontaUegro 11-16145 GenovaItaly GE AvioAero S.p.A. V.I Maggio99 1-10040 Rivalta(TO)-Italy

The suction side boundary layer evolution of a high-lift low-pressure turbine cascade has been experimentally in- vestigated at low and high free-stream turbulence intensity conditions. Measurements have been carded out in order to analyze the boundary layer transition and separation processes at a low Reynolds nttmber, under both steady and unsteady inflows. Static pressure distributions along the blade surfaces as well as total pressure distri- butions in a downstream tangential plane have been measured to evaluate the overall aerodynamic efficiency of the blade for the different conditions. particle. Image Velocimetry has been adopted to analyze the time-mean and time-varying velocity fields. The flow field has been surveyed in two orthogonal planes （a blade-to-blade plane and a wall-parallel one）. These measurements allow the identification of the Kelvin-Helmholtz large scale cohe- rent structures shed as a consequence of the boundary layer laminar separation under steady inflow, as well as the investigation of the three-dimensional effects induced by the intermittent passage of low and high speed streaks. A close inspection of the time-mean velocity profiles as well as of the boundary layer integral parameters helps to characterize the suction side boundary layer state, thus justifying the influence of free-stream turbulence intensity on the blade aerodynamic losses measured under steady and unsteady inflows.

关键词： profile losses high-lift profiles free-stream turbulence streaks unsteady flows.

profile and Secondary Flow Losses in a High-Lift LpT Blade Cascade at Different Reynolds Numbers under Steady and Unsteady Inflow Conditions

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Journal of Thermal Science 2012年第6期21卷 483-491页

作者： Satta F. simoni D. Ubaldi M. Zunino p. Bertini F. DIMSET-Università di Genova Via Montallegro 1I-16145 GenovaItaly Avio S.p.A. Viale I Maggio 56I-10040 Rivalta(TO)-Italy

The aerodynamic flow field downstream of a Low-pressure High-Lift(HL)turbine cascade has been experimentally investigated for different Reynolds numbers under both steady and unsteady inflows,in order to analyse the cascade performance under real engine operating *** Reynolds number has been varied in the range 100000pper limits are typical of cruise and take-off/landing conditions,*** effects induced by the incoming wakes at the reduced frequency f+=0.62 on both profile and secondary flow losses have been *** pressure,velocity and secondary kinetic energy distributions at the downstream tangential plane have been measured by means of a miniaturized 5-hole *** quantities provide information on both blade wake and secondary flow structures(passage and horse-shoe vortices).The analysis of the results allows the evaluation of the aerodynamic performance of the HL front-loaded blade in terms of both profile and secondary losses.

关键词： profile losses secondary flow losses high-lift profdes unsteady inflow LpT blade.

Turbine Blade Boundary Layer Separation Suppression via Synthetic Jet: an Experimental and Numerical Study

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Journal of Thermal Science 2012年第5期21卷 404-412页

作者： Bernardini C. Carnevale M. Manna M. Martelli F. simoni D. Zunino p. Università degli Studi di Firenze Firenze Italy Università degli Studi di Napoli Federico Ⅱ Napoli Italy Università degli Studi di Firenze FirenzeItaly Università degli Studi di Genova Genova Italy

The present paper focuses on the analysis of a synthetic jet device (with a zero net massflow rate) on a separated boundary layer. Separation has been obtained on a flat plate installed within a converging-diverging test section specifically designed to attain a local velocity distribution typical of a high-lift LpT blade. Both experimental and numerical investigations have been carried out. Unsteady RANS results have been compared with experiments in terms of time-averaged velocity and turbulence intensity distributions. Two different Reynolds number cases have been investigated, namely Re = 200,000 and Re = 70,000, which characterize low-pressure turbine operating conditions during take-off/landing and cruise. A range of synthetic jet aerodynamic parameters (Strouhal number and blowing ratio) has been tested in order to analyze the features of control-separated boundary layer interaction for the aforementioned Reynolds numbers.

关键词： Synthetic Jet Separated Flow Active Flow Control Unsteady Flow Ultra High Lift LpT.

An Experimental Investigation of the Dissipation Mechanisms in the Suction Side Boundary Layer of a Turbine Blade

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Journal of Thermal Science 2008年第4期17卷 289-297页

作者： Francesca Satta Daniele simoni Marina Ubaldi pietro Zunino Dipartimento di Macchine Sistemi Energetici e Trasporti-Università di Genova

The present work is part of an extensive experimental activity carried out by the authors in recent years aimed at investigating the boundary layer transition phenomenon in turbine blades. The large scale of the cascade and the use of advanced LDV instrumentation and precision probe traversing mechanism resulted in high degree of spatial resolution and high accuracy of measurements. The main dissipation mechanism determining the profile losses in turbomachinery blades is the work of deformation of the mean motion within the boundary layer operated by both viscous and turbulent shear stresses. In the present paper, the local viscous and turbulent deformation works have been directly evaluated from the detailed measurements of boundary layer mean velocity and Reynolds shear stress. The results show the distributions and the relative importance of the viscous and turbulent contributions to the loss production, in relation with the boundary layer states occurring along the turbine profile.

关键词： Axial flow turbines profile boundary layer Energy dissipation mechanism Boundary layer transition Laser Doppler measurements.