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Geo-Spatial Information Science 2018年第3期21卷 257-271页

作者： Gloria Bordogna Steven Capelli daniele e.ciriello Giuseppe Psaila CNR IReA MilanoItaly DISCo Universitádegli studi di Milano BicoccaSesto San GiovanniItaly DIGIP University of BergamoDalmineItaly

The paper discusses the need of a high-level query language to allow analysts,geographers and,in general,non-programmers to easily cross-analyze multi-source VGI created by means of apps,crowd-sourced data from social networks and authoritative geo-referenced data,usually represented as JSON data sets(nowadays,the de facto standard for data exported by social networks).Since an easy to use high-level language for querying and manipulating collections of possibly geo-tagged JSON objects is still unavailable,we propose a truly declarative language,named J-CO-QL,that is based on a well-defined execution model.A plug-in for a GIS permits to visualize geo-tagged data sets stored in a NoSQL database such as MongoDB;furthermore,the same plug-in can be used to write and execute J-CO-QL queries on those *** paper introduces the language by exemplifying its operators within a real study case,the aim of which is to understand the mobility of people in the neighborhood of Bergamo ***-analysis of data about transportation networks and VGI from travelers is performed,by means of J-CO-QL language,capable to manipulate and transform,combine and join possibly geo-tagged JSON objects,in order to produce new possibly geo-tagged JSON objects satisfying users’needs.

关键词： Cross-analysis framework comparing VGI crowd-sourced and authoritative geographical data JSON data-sets declarative query language heterogeneous data-sets

On “Over-Sized” High-Gain Practical Observers for Nonlinear Systems

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Ieee/CAA Journal of Automatica Sinica 2018年第3期5卷 691-698页

作者： daniele Carnevale Corrado Possieri Antonio Tornambè Dipartimento di Ingegneria Civile e Ingegneria Informatica Universita di Roma Tor Vergata

In this paper,it is shown that the performances of a class of high-gain practical observers can be improved by estimating the time derivatives of the output up to an order that is greater than the dimension of the system, which is assumed to be in observability form and, possibly, time-varying. Such an improvement is achieved without increasing the gain of the observers, thus allowing their use in a wide variety of control and identification applications.

关键词： Filtering properties nonlinear systems observability observer design

Myelin positron emission tomography(PeT) imaging in multiple sclerosis

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Neural Regeneration Research 2020年第10期15卷 1842-1843页

作者： daniele de Paula Faria Laboratory of Nuclear Medicine (LIM-43) Departamento de Radiologia e Oncologia Faculdade de Medicina Universidade de Sao Paulo

Multiple sclerosis(MS)is a neurodegenerative disease characterized by inflammation and *** are focused on encountering remyelination therapies that can be applied to delaying,or even decreasing,the motor and cognitive disabilities caused by the *** cellular/molecular changes in MS are dynamic,with inflammation,demyelination and remyelination inducing progressive neurodegenerative changes in the central nervous system,as a ***,the imaging methods for accompanying the process are,as yet,shortcoming.

关键词： inflammation sclerosis myelin

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.

Zooming in Ree and Other Trace elements on Conodonts:Does Taxonomy Guide Diagenesis?

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Journal of earth Science 2021年第3期32卷 501-511页

作者： Luca Medici Martina Savioli Annalisa Ferretti daniele Malferrari National Research Council of Italy Institute of Methodologies for Environmental AnalysisC.da S.Loja-Zona Industriale85050 Tito ScaloPotenzaItaly Department of Chemical and Geological Sciences University of Modena and Reggio EmiliaVia Campi 10341125 ModenaItaly

Conodont elements are calcium phosphate(apatite structure)mineralized remains of the cephalic feeding apparatus of an extinct marine *** to the high affinity of apatite for rare earth elements(Ree)and other high field strength elements(HFSe),conodont elements were frequently assumed to be a reliable archive of sea-water composition and changes that had occurred during ***,the crystallinity index of bioapatite,i.e.,the rate of crystallinity of biologically mediated apatite,should be generally linearly dependent on diagenetic alteration as the greater(and longer)the pressure and temperature to which a crystal is exposed,the greater the resulting *** this study,we detected the uptake of HFSe in conodont elements recovered from a single stratigraphic horizon in the Upper Ordovician of Normandy(France).Assuming therefore that all the specimens have undergone an identical diagenetic history,we have assessed whether conodont taxonomy(and morphology)impacts HFSe uptake and crystallinity *** found that all conodont elements are characterized by a clear diagenetic signature,with minor but significant differences among *** distinctions are evidenced also by the crystallinity index values which show positive correlations with some elements and,accordingly,with diagenesis;however,correlations with the crystallinity index strongly depend on the method adopted for its calculation.

关键词： bioapatite crystallinity index HFSe laser ablation mass spectrometry microdiffraction Normandy Ordovician

On the calibration of rotational augmentation models for wind turbine load estimation by means of CFD simulations

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Acta Mechanica Sinica 2020年第2期36卷 306-319页

作者： Belen Soledad Burgos Tafur elia daniele Bernhard Stoevesandt Philipp Thomas Fraunhofer IWeS Am Seedeich 4527572 BremerhavenGermany Flensburg University of Applied Sciences Wind Energy Technology InstituteNordstraße224943 FlensburgGermany

In this work the improved version of an engineering model which accounts for rotational augmentation effects by means of computational fluid dynamics(CFD)calibration is explored and *** on an analysis of the NReL Phase VI wind turbine,the novel modeling is presented,which uses as base line the formulation proposed by Chaviaropoulos and *** model is calibrated based on CFD simulations using *** corresponding correction of the two dimensional polars is straightforward implemented within MoWiT,an in-house software for load *** novel formulation results in improved lift and drag coefficients prediction in all considered cases,reducing the deviation with respect to the rotating CFD cases down to few *** optimal configuration including the correction for tip effects of Shen shows better agreements at the very tip of the *** the range of applicability for large wind turbine rotor blades based on a virtual 10MW rotor model is discussed.

关键词： calculation. rotational correction

A Semi-Lagrangian Spectral Method for the Vlasov-Poisson System Based on Fourier, Legendre and Hermite Polynomials

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Communications on Applied Mathematics and Computation 2019年第3期1卷 333-360页

作者： Lorella Fatone daniele Funaro Gianmarco Manzini Dipartimento di Matematica University degli Studi di CamerinoCamerinoItaly Dipartimento di Scienze Chimiche e Geologiche Universita degli Studi di Modena e Reggio EmiliaModenaItaly Group T-5 Applied Mathematics and Plasma PhysicsTheoretical DivisionLos Alamos National LaboratoryLos AlamosNMUSA

In this work, we apply a semi-Lagrangian spectral method for the Vlasov-Poisson system, previously designed for periodic Fourier discretizations, by implementing Legendre polynomials and Hermite functions in the approximation of the distribution function with respect to the velocity variable. We discuss second-order accurate-in-time schemes, obtained by coupling spectral techniques in the space-velocity domain with a BDF timestepping scheme. The resulting method possesses good conservation properties, which have been assessed by a series of numerical tests conducted on some standard benchmark problems including the two-stream instability and the Landau damping test cases. In the Hermite case, we also investigate the numerical behavior in dependence of a scaling parameter in the Gaussian weight. Confirming previous results from the literature, our experiments for different representative values of this parameter, indicate that a proper choice may significantly impact on accuracy, thus suggesting that suitable strategies should be developed to automatically update the parameter during the time-advancing procedure.

关键词： Spectral methods Semi-Lagrangian methods High-order Hermite functions Vlasov-Poisson equations Mass conservation

Discrete element method model calibration and validation for the spreading step of the powder bed fusion process to predict the quality of the layer surface

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Particuology 2024年第11期94卷 261-273页

作者： Marco Lupo Sina Zinatlou Ajabshir daniele Sofia Diego Barletta Massimo Poletto Department of Industrial engineering University of SalernoVia Giovanni Paolo II13284084FiscianoSAItaly Granutools Rue Jean Lambert Defrene 1074340 AwansBelgium Dipartimento di Ingegneria Informatica ModellisticaElettronica e Sistemistica dell’Universita’della CalabriaVia Pietro Bucci87036 Rende CS(CS)Italy

A Discrete element Method model,including interparticle cohesive forces,was calibrated and validated to develop a tool to predict the powder layer’s quality in the powder bed fusion *** elastic contact model was used to describe cohesive interparticle *** surface energy of the model particles was estimated by assuming that the pull-off force should provide the strength of the material evaluated at low consolidation with shear test *** particle rolling friction was calibrated considering the bulk density of the layer produced by the spreading *** model was validated with the experiments by comparing the wavelet power spectra obtained with the simulations with those of the experimental layers illuminated by grazing *** calibration proposed in this study demonstrated superior performance compared to our previous methods,which relied on measuring the angle of repose and unconfined yield strength.

关键词： Additive manufacturing Powder bed fusion Laser sintering Powder spreading Discrete element method Wavelet transform

Three Gorges Dam stability monitoring with time-series InSAR image analysis

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Science China earth Sciences 2011年第5期54卷 720-732页

作者： WANG Teng daniele PeRISSIN Fabio ROCCA LIAO Ming-Sheng State Key Laboratory of Information engineering in Surveying Mapping andRemote Sensing Wuhan University Wuhan 430079 China Dipartimento di elettronica e lnformazione Politecnico di Milano Milan 20133 Italy Institute of Space and earth Information Science Chinese University of Hong Kong Hong Kong China

In this paper,we carried out a combination of permanent scatterer and quasi permanent scatterer time-series InSAR image analyses to extract geometric information over the area of the Three Gorges *** the first time,we measured and analyzed the deformation of the Three Gorges Dam and its surrounding area using 40 SAR images acquired from 2003 to *** results indicate that the temporal deformation of the left part of the dam has ceased and that the deformation of the dam was influenced by the changing level of the Yangtze *** deformation due to varying temperature is also *** obtained results agree well with the published results of the Three Gorges Dam deformation obtained by employing conventional survey *** also found that there is an area of abnormal subsidence near Zigui *** paper demonstrates the potential of time-series InSAR image analysis in the monitoring of dam stability and measurement of subsidence.

关键词： Three Gorges Project deformation monitoring InSAR permanent scatterer analysis

experimental and Numerical Analysis of Cavity/Mean-Flow Interaction in Low Pressure Axial Flow Turbines

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Journal of Thermal Science 2021年第6期30卷 2178-2185页

作者： BARSI Dario COSTA Carlo LeNGANI Davide SIMONI daniele VeNTURINO Giulio ZUNINO Pietro DIMe-Universita di Genova Via Montallegro 11-16145 Genova

The increasing performance of modern aeroengines led the research towards the optimization of machine components not deeply analyzed in the *** this context,the mechanisms driving the interaction process between the secondary flows evolving at the hub of low-pressure turbines with the rotor-stator cavity systems have been poorly investigated in the *** this work,an experimental and numerical analysis of the interaction between the endwall near wall flow and the leakage flow of a real cavity system is *** experimental results were carried out in the annular low-pressure axial flow turbine of the University of *** blade loading and pressure distributions into the cavity,as well as the measured total pressure loss coefficient,have been used for a proper validation of CFD *** steady and unsteady calculations were carried out through the commercial solver ***,several numerical approaches have been tested into this work:RANS,Non Linear Harmonic(NLH),and *** most promising CFD techniques have been firstly identified by comparison with experimental results and then systematically employed to extend the analysis of secondary flow-cavity flow interaction to positions and quantities not available from the *** characterizing the mean flow-cavity flow interaction process will be shown to cover a great amount of the overall stage losses and should be properly accounted for the design of future optimized cavity configurations.

关键词： axial flow turbine cavity mean-flow interaction experimental analysis CFD