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Journal of Thermal Science 2015年第6期24卷 526-534页

作者： Michele Marconcini roberto Pacciani Andrea Arnone University of Florence Department of Industrial Engineering Via Santa Marta

The aerodynamic performance of a gas turbine nozzle vane cascade was investigated over a range of Mach and Reynolds *** work is part of a vast research project aimed at the analysis of fluid dynamics and heat transfer phenomena in cooled *** this paper computed results on the"solid vane"(without cooling devices)are presented and discussed in comparison with experimental *** measurements were provided by the University of Bergamo where the experimental campaign was carried out by means of a subsonic wind *** impact of boundary layer transition is investigated by using a novel laminar kinetic energy transport model and the widely used Langtry-Menterγ-Reθ,t *** comparison between calculations and measurements is presented in terms of blade loading distributions,total pressure loss coefficient contours downstream of the cascade,and velocity/turbulence-intensity profiles within the boundary layer at selected blade surface locations at *** will be shown how transitional calculations compare favorably with experiments.

关键词： Gas turbine CFD validation transition model secondary flows

Comparative Analysis of PSO Algorithms for PID Controller Tuning

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Chinese Journal of Mechanical Engineering 2014年第5期27卷 928-936页

作者： TIMAC Goranka BRAUT Sanjin ZIGULI roberto Faculty of Engineering University of Rijeka

The active magnetic bearing（AMB）suspends the rotating shaft and maintains it in levitated position by applying controlled electromagnetic forces on the rotor in radial and axial *** the development of various control methods is rapid,PID control strategy is still the most widely used control strategy in many applications,including *** order to tune PID controller,a particle swarm optimization（PSO）method is ***,a comparative analysis of particle swarm optimization（PSO）algorithms is carried out,where two PSO algorithms,namely（1）PSO with linearly decreasing inertia weight（LDW-PSO）,and（2）PSO algorithm with constriction factor approach（CFA-PSO）,are independently tested for different PID *** computer simulations are carried out with the aim of minimizing the objective function defined as the integral of time multiplied by the absolute value of error（ITAE）.In order to validate the performance of the analyzed PSO algorithms,one-axis and two-axis radial rotor/active magnetic bearing systems are *** results show that PSO algorithms are effective and easily implemented methods,providing stable convergence and good computational efficiency of different PID structures for the rotor/AMB ***,the PSO algorithms prove to be easily used for controller tuning in case of both SISO and MIMO system,which consider the system delay and the interference among the horizontal and vertical rotor axes.

关键词： PID gain tuning rotor/AMB system PID structures particle swarm optimization

Detecting the filamentary structure of 3D point clouds:Proposal of a wavelet-based method

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International Journal of Modeling, Simulation, and Scientific Computing 2017年第3期8卷 311-336页

作者： roberto D’Ercole Department of Biomedical and Clinical Sciences“L.Sacco”University of Milan Via G.B.Grassi 74 Milan 20157Italy

The analysis of the filamentary structure of the cosmo as well as that of the internal structure of the polar ice suggests the development of models based on three-dimensional(3D)point processes.A point process,regarded as a random measure,can be expressed as a sum of Delta Dirac measures concentrated at some random *** integration with respect to the point process leads the continuous wavelet transform of the process *** possible mother wavelets,we propose the application of the Mexican hat and the Morlet wavelet in order to implement the scale-angle energy density of the process,depending on the dilation parameter and on the three angles which define the direction in the Euclidean *** indicator proves to be a sensitive detector of any variation in the direction and it can be successfully implemented to study the isotropy or the filamentary structure in 3D point patterns.

关键词： 3D Continuous wavelet transform energy density scale-angle energy density Mexican hat Morlet mother wavelet random measure filamentary structure rotation matrix Euler angles isotropy anisotropy

Combining X-ray microtomography with computer simulation for analysis of granular and porous materials

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Particuology 2010年第2期8卷 81-99页

作者： roberto Moreno-Atanasio Richard A. Williams Institute of Particle Science and Engineering School of Process Environmental and Materials Engineering University of Leeds Leeds LS2 9JT UK

The use of X-ray microtomographic （XMT） methods in analysing particulate systems has expanded rapidly in recent years with the availability of affordable desk-top apparatus. This review presents a summary of the major applications in which computer simulations are explicitly coupled with XMT in the area of granular and porous materials. We envisage two main ways of establishing the coupling between both techniques, based on the transference or exchange of information by using physical or geometrical parameters （i.e. a parametric link through fitting to a process model） or through the direct use of3D XMT digital images （i.e. comparing image pixels and features directly）. Examples of coupled applications are shown for the study of transport properties of rocks, particle packing, mechanical loading and sintering. Often, the link between XMT and computer simulations is based on visual comparisons and we conclude that the use of quantitative parameters such as the number of interparticle contacts, force networks or granule shape to link both techniques is still underrepresented in the literature. Strategies to provide a more robust and quantitative approach to optimise the information obtained from such tomography analyses are proposed. 2010 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

关键词： X-ray microtomographyGranular flowComputer modellingLattice Boltzmann methodDiscrete element method

Measuring nonlinearity by means of static parameters in Bernoulli binary sequences distribution:A brief approach

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第3期11卷 68-77页

作者： Charles roberto Telles Secretary of State for Education and Sport of ParanáAv.Água Verde 2140Curitiba 80240-070/Vila IzabelBrazil

This paper analyzes Bernoulli’s binary sequences in the representation of empirical nonlinear events,analyzing the distribution of natural resources,population sizes and other variables that influence the possible outcomes of resource’s *** the event as a nonlinear system and the metrics of analysis consisting of two dependent random variables 0 and 1,with memory and probabilities in maximum finite or infinite lengths,constant and equal to 1/2 for both variables(stationary process).The expressions of the possible trajectories of metric space represented by each binary parameter remain constant in sequences that are repeated alternating the presence or absence of one of the binary variables at each iteration(symmetric or asymmetric).It was observed that the binary variables X_(1)and X_(2)assume on time T_(k)→∞specific behaviors(geometric variable)that can be used as management tools in discrete and continuous nonlinear systems aiming at the optimization of resource’s usage,nonlinearity analysis and probabilistic distribution of trajectories occurring about random *** this way,the paper presents a model of detecting fixed-point attractions and its probabilistic distributions at a given population-resource *** means that coupling oscillations in the event occur when the binary variables X_(1)and X_(2)are limited as a function of time Y.

关键词： Coupling functions and nonparametric statistics Bernoulli binary sequences nonlinearity metrics pattern formation stability and predictive analysis

On the electrophysiology of the atrial fast conduction system:an uncertain quantification study

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Acta Mechanica Sinica 2021年第2期37卷 264-278页

作者： Giulio Del Corso roberto Verzicco Francesco Viola GSSI(Gran Sasso Science Institute) L'AquilaItaly University of Roma Tor Vergata RomeItaly POF Group University of TwenteEnschedeThe Netherlands

Cardiac modeling entails the epistemic uncertainty of the input parameters,such as bundles and chambers geometry,electrical conductivities and cell parameters,thus calling for an uncertainty quantification(UQ)*** the cardiac activation and the subsequent muscular contraction is provided by a complex electrophysiology system made of interconnected conductive media,we focus here on the fast conductivity structures of the atria(internodal pathways)with the aim of identifying which of the uncertain inputs mostly influence the propagation of the depolarization ***,the distributions of the input parameters are calibrated using data available from the literature taking into account gender *** output quantities of interest(Qols)of medical relevance are defined and a set of metamodels(one for each Qol)is then trained according to a polynomial chaos expansion(PCE)in order to run a global sensitivity analysis with non-linear variance-based SoboF indices with confidence intervals evaluated through the bootstrap *** most sensitive parameters on each Qol are then identified for both genders showing the same order of importance of the model inputs on the electrical ***,the probability distributions of the Qols are obtained through a forward sensitivity analysis using the same trained *** results that several input parameters-including the position of the internodal pathways and the electrical impulse applied at the sinoatrial node一have a little influence on the Qols ***-versa the electrical activation of the atrial fast conduction system is sensitive on the bundles geometry and electrical conductivities that need to be carefully measured or calibrated in order for the electrophysiology model to be accurate and predictive.

关键词： Uncertainty quantification Global sensitivity analysis Forward analysis Atrial modelling Electrophysiology Monodomain model

Inverse synthetic aperture radar imaging based on sparse signal processing

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Journal of Central South University 2011年第5期18卷 1609-1613页

作者：邹飞黎湘 roberto Togneri Institute of Space Electronic Technology National University of Defense Technology School of Electrical Electronic and Computer EngineeringThe University of Western AustraliaTerthAustralia

Based on the measurement model of inverse synthetic aperture radar (ISAR) within a small aspect sector,an imaging method was presented with the application of sparse signal *** method can form higher resolution inverse synthetic aperture radar images from compensating incomplete measured data,and improves the clarity of the images and makes the feature structure much more clear,which is helpful for target *** simulation results indicate that this method can provide clear ISAR images with high contrast under complex motion case.

关键词： ISAR imaging sparse component analysis target recognition high resolution target image

The local mammalian target of rapamycin(mTOR) modulation:a promising strategy to counteract neurodegeneration

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Neural Regeneration Research 2019年第10期14卷 1711-1712页

作者： Diego Dolcetta roberto Dominici Neuroscience Center RomeItaly (Dolcetta D) Clinical Chemistry LaboratoryMagenta HospitalASST Ovest MilaneseMilanItaly

Alzheimer’s disease (AD) and the evolution of the “Amyloid Hypothesis”: The primary risk factor for dementia is aging, as the overwhelming majority of individuals who have the disease (~95%) are 65 years old or older, and the rate of development of AD doubles roughly every five years from that age, peaking at a nearly 50% population prevalence by the age of 85. The disease is progressive and irreversible, with an average time course of 8 to 10 years. Regardless of catastrophic forecasts for the next decades, its actual prevalence has huge family and social costs.

关键词： Alzheimer’s disease primary risk factor family and social costs

Moment Maps and Equivariant Volumes

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2155-2188页

作者： Alberto DELLA VEDOVA roberto PAOLETTI Dipartimento di Matematica Università degli Studi di Parma Viale Dipartimento di Matematica e Applicazioni Università degli Studi di Milano Bicocca

The study of the volume of big line bundles on a complex projective manifold M has been one of the main veins in the recent interest in the asymptotic properties of linear series. In this article, we consider an equiv... 详细信息

关键词： big line bundle asymptotic invariant moment map GIT quotient

Lights and shadows in the evolutionary patterns of insular bovids

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Integrative Zoology 2014年第2期9卷 213-228页

作者： roberto ROZZI Maria Rita PALOMBO Department of Earth Sciences SapienzaUniversity of RomeRomeItaly Consiglio Nazionale delle Ricerche-Istituto di Geologia Ambientale e Geoingegneria(DNR-IGAG) RomeItaly

Endemic bovids are intriguing elements of insular *** living species include the Japanese serow(Cap-ricornis crispus)and the Formosan serow(***),the tamaraw from Mindoro,Philippines,(Bubalus min-dorensis)and the anoas(*** and ***),2 species of dwarf buffalos endemic to Sulawesi,*** endemic bovids are only recorded in some Asian,North American and Western Mediterranean *** we present a comprehensive overview of the changes in body size and evolutionary patterns ex-hibited by both extant and extinct insular *** appraisal indicates that each insular representative of Bo-vidae shows its own peculiar evolutionary model,albeit some parallel trends exist(*** in body size,allometric changes in limb bones,alteration of the life history traits).Some changes in morphology(*** simplification of horn cores,the increase in hypsodonty,the acquisition of a‘low-gear’locomotion),for in-stance,appear as common,albeit not general,patterns triggered by a combination of selective *** size patterns support the‘generality of the island rule’and suggest that biotic interaction had/have a major role in in-fluencing body size evolution in these species,although in different ways on different *** things consid-ered,available evidence suggest that a major role in the evolution of insular bovids is played by the structure of the insular community,the nature of available niches and by the dynamics of ecological interactions.

关键词： evolutionary island shadow