Results for "M. Angeli"

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Valley Jahn-Teller effect in twisted bilayer grapheneApr 12 2019Apr 16 2019The surprising insulating and superconducting states of narrow-band graphene twisted bilayers have been mostly discussed so far in terms of strong electron correlation, with little or no attention to phonons and electron-phonon effects. We found that, ... More
Limit theorems for cloning algorithmsFeb 01 2019Large deviations for additive path functionals of stochastic processes have attracted significant research interest, in particular in the context of stochastic particle systems and statistical physics. Efficient numerical `cloning' algorithms have been ... More
Decoherence and collective effects in critical mediaMar 29 2019We investigate the influence of critical phenomena on two distinct physical processes: the center-of-mass decoherence of a single emitter, and the collective radiation of two emitters. We address these different physical mechanisms with an unified formalism ... More
Asymptotic estimates related to an integro differential equationApr 14 2014The paper deals with an integrodifferential operator which models numerous phenomena in superconductivity, in biology and in viscoelasticity. Initialboundary value problems with Neumann, Dirichlet and mixed boundary conditions are analyzed. An asymptotic ... More
A priori estimates for excitable modelsApr 16 2013The reaction-diffusion system of Fitzhugh Nagumo is considered. The initial- boundary problems with Neumann and Dirichlet conditions are analyzed. By means of an equivalent semilinear integrodifferential equation which characterizes several dissipative ... More
On hereditary models of polymersMar 02 2012An equivalence between an integro-differential operator M and an evolution operator Ln is determined. From this equivalence the fundamental solution of Ln is estimated in terms of the fundamental solution related to the third-order operator L1 whose behavior ... More
Asymptotic analysis for the strip problem related to a parabolic third - order operatorMar 10 2012Aim of this paper is the qualitative analysis of a boundary value problem for a third order non linear parabolic equation which describes several dissipative models. When the source term is linear, the problem is explictly solved by means of a Fourier ... More
On exponentially shaped Josephson junctionsFeb 23 2012The paper deals with a third order semilinear equation which char- acterizes exponentially shaped Josephson junctions in superconductivity. The initial-boundary problem with Dirichlet conditions is analyzed. When the source term F is a linear function, ... More
Parabolic - hyperbolic boundary layerJul 09 2012A boundary value problem related to a parabolic higher order operator with a small parameter is analized. When the small parameter tends to zero, the reduced operator is hyperbolic. When t tends to infinity a parabolic hyperbolic boundary layer appears. ... More
A wave equation perturbed by viscous terms: fast and slow times diffusion effects in a Neumann problemOct 21 2018A Neumann problem for a wave equation perturbed by viscous terms with small parameters is considered. The interaction of waves with the diffusion effects caused by a higher-order derivative with small coefficient {\epsilon}, is investigated. Results obtained ... More
On a Model of Superconductivity and BiologyMar 02 2012The paper deals with a semilinear integrodifferential equation that characterizes several dissipative models of Viscoelasticity, Biology and Superconductivity. The initial - boundary problem with Neumann conditions is analyzed. When the source term F ... More
Mathematical Contributions to the Dynamics of the Josephson Junctions: State of the Art and Open ProblemsSep 10 2015Mathematical models related to some Josephson junctions are pointed out and attention is drawn to the solutions of certain initial boundary problems and to some of their estimates. In addition, results of rigorous analysis of the behaviour of these solutions ... More
From optimal stopping boundaries to Rost's reversed barriers and the Skorokhod embeddingMay 11 2015Jan 08 2017We provide a new probabilistic proof of the connection between Rost's solution of the Skorokhod embedding problem and a suitable family of optimal stopping problems for Brownian motion with finite time-horizon. In particular we use stochastic calculus ... More
Existence, uniqueness and a priori estimates for a non linear integro-differential equationMar 02 2012The paper deals with the explicit calculus and the properties of the fundamental solution K of a parabolic operator related to a semilinear equation that models reaction diffusion systems with excitable kinetics. The initial value problem in all of the ... More
On the Fitzhugh-Nagumo modelFeb 26 2012The initial value problem P0, in all of the space, for the spatio - temporal FitzHugh - Nagumo equations is analyzed. When the reaction kinetics of the model can be outlined by means of piecewise linear approximations, then the solution of P0 is explicitly ... More
Diffusion effects on a superconductive modelNov 06 2012A superconductive model characterized by a third order parabolic operator L" is analysed. When the viscous terms, represented by higher - order deriva- tives, tend to zero, a hyperbolic operator L0 appears. Furthermore, if P" is the Dirichlet initial ... More
Asymptotic effects of boundary perturbations in excitable systemsApr 14 2013A Neumann problem in the strip for the Fitzhugh Nagumo system is consid- ered. The transformation in a non linear integral equation permits to deduce a priori estimates for the solution. A complete asymptotic analysis shows that for large t the effects ... More
Non linear travelling waves with diffusionMar 04 2012A third order parabolic operator L_\epsilon typical of a non linear wave operator cal L_0 perturbed by viscous terms, is analyzed. Some particular solutions related to L_0 are explicitly determined and the initial value problem for L_\epsilon is considered. ... More
Generalized crested products of Markov chainsJun 24 2010We define a finite Markov chain, called generalized crested product, which naturally appears as a generalization of the first crested product of Markov chains. A complete spectral analysis is developed and the $k$-step transition probability is given. ... More
Wreath product of matricesJul 09 2015We introduce a new matrix product, that we call the wreath product of matrices. The name is inspired by the analogous product for graphs, and the following important correspondence is proven: the wreath product of the adjacency matrices of two graphs ... More
Diffusion and wave behaviour in linear Voigt modelMar 10 2012A boundary value problem related to a third- order parabolic equation with a small parameter is analized. This equation models the one-dimensional evolution of many dissipative media as viscoelastic fluids or solids, viscous gases, superconducting materials, ... More
Valley Jahn-Teller effect in twisted bilayer grapheneApr 12 2019The surprising insulating and superconducting states of narrow-band graphene twisted bilayers have been mostly discussed so far in terms of strong electron correlation, with little or no attention to phonons and electron-phonon effects. We found that, ... More
Global $C^1$ Regularity of the Value Function in Optimal Stopping ProblemsDec 11 2018We show that if either the process is strong Feller and the boundary point is probabilistically regular for the stopping set, or the process is strong Markov and the boundary point is probabilistically regular for the interior of the stopping set, then ... More
Existence and uniqueness of solutions of a class of 3rd order dissipative problems with various boundary conditions describing the Josephson effectMay 11 2012We prove existence and uniqueness of solutions of a large class of initial-boundary-value problems characterized by a quasi-linear third order equation (the third order term being dissipative) on a finite space interval with Dirichlet, Neumann or pseudoperiodic ... More
Optimal stopping for the exponential of a Brownian bridgeMar 29 2019In this paper we study the problem of stopping a Brownian bridge $X$ in order to maximise the expected value of an exponential gain function. In particular, we solve the stopping problem $$\sup_{0\le \tau\le 1}\E[\mathrm{e}^{X_\tau}]$$ which was posed ... More
On the free boundary of an annuity purchaseJul 29 2017Jul 12 2018It is known that the decision to purchase an annuity may be associated to an optimal stopping problem. However, little is known about optimal strategies, if the mortality force is a generic function of time and if the `subjective' life expectancy of the ... More
On asymptotic effects of boundary perturbations in exponentially shaped Josephson junctionsNov 25 2013Jan 02 2014A parabolic integro differential operator L, suitable to describe many phenomena in various physical fields, is considered. By means of equivalence between L and the third order equation describing the evolution inside an exponentially shaped Josephson ... More
New Approach to the Stability of Chemical Reaction Networks: Piecewise Linear in Rates Lyapunov FunctionsJul 02 2014Sep 07 2016Piecewise-Linear in Rates (PWLR) Lyapunov functions are introduced for a class of Chemical Reaction Networks (CRNs). In addition to their simple structure, these functions are robust with respect to arbitrary monotone reaction rates, of which mass-action ... More
Analysing Multiple Epidemic Data SourcesAug 13 2018Evidence-based knowledge of infectious disease burden, including prevalence, incidence, severity and transmission, in different population strata and locations, and possibly in real time, is crucial to the planning and evaluation of public health policies. ... More
Data Mining in Gamma Astrophysics ExperimentsMar 24 2005Data mining techniques, including clustering and classification tasks, for the automatic information extraction from large datasets are increasingly demanded in several scientific fields. In particular, in the astrophysical field, large archives and digital ... More
Perspects in astrophysical databasesFeb 09 2004Astrophysics has become a domain extremely rich of scientific data. Data mining tools are needed for information extraction from such large datasets. This asks for an approach to data management emphasizing the efficiency and simplicity of data access; ... More
Data Management and Mining in Astrophysical DatabasesJul 12 2003Jul 16 2003We analyse the issues involved in the management and mining of astrophysical data. The traditional approach to data management in the astrophysical field is not able to keep up with the increasing size of the data gathered by modern detectors. An essential ... More
Robust Lyapunov Functions for Reaction Networks: An Uncertain System FrameworkSep 07 2015We present a framework to transform the problem of finding a Lyapunov function of a Chemical Reaction Network (CRN) in concentration coordinates with arbitrary monotone kinetics into finding a common Lyapunov function for a linear parameter varying system ... More
Non linear problems in dissipative modelsMar 09 2012Aim of the paper is the qualitative analysis of a quasi-linear parabolic third order equation, which describes the evolution in a large class of dissipative models. As examples of some typical boundary problems, both Dirichlet's and Neumann's type boundary ... More
Optimal stopping of a Hilbert space valued diffusion: an infinite dimensional variational inequalityJul 03 2012Jan 31 2015A finite horizon optimal stopping problem for an infinite dimensional diffusion $X$ is analyzed by means of variational techniques. The diffusion is driven by a SDE on a Hilbert space $\mathcal{H}$ with a non-linear diffusion coefficient $\sigma(X)$ and ... More
Wave hierarchies in viscoelasticityMar 02 2012An evolution operator L_n with n arbitrary, typical of several models, is analyzed. When n= 1, the operator characterizes the standard linear solid of viscoelasticity, whose properties are already established in previous papers. The fundamental solution ... More
Existence and uniqueness results for a class of non linear modelsMar 11 2012The qualitative analysis of the initial value problem P related to a non linear third order parabolic equation typical of diffusive models is discussed. Some basic properties of the the fundamental solution of a related linear operator are determined ... More
Localization of light in subradiant Dicke states: a mobility edge in the imaginary axisFeb 15 2017May 24 2018Anderson localization of light in three dimensions has challenged experimental and theoretical research for the last decades. Localization of light in cold atomic systems presents strong differences from the standard problem of localization since one ... More
Counting dimer coverings on self-similar Schreier graphsSep 06 2011Sep 12 2011We study partition functions for the dimer model on families of finite graphs converging to infinite self-similar graphs and forming approximation sequences to certain well-known fractals. The graphs that we consider are provided by actions of finitely ... More
Nash equilibria of threshold type for two-player nonzero-sum games of stoppingAug 17 2015Aug 02 2017This paper analyses two-player nonzero-sum games of optimal stopping on a class of linear regular diffusions with not non-singular boundary behaviour (in the sense of It\^o and McKean (1974), p.\ 108). We provide sufficient conditions under which Nash ... More
Partition functions of the Ising model on some self-similar Schreier graphsMar 02 2010We study partition functions and thermodynamic limits for the Ising model on three families of finite graphs converging to infinite self-similar graphs. They are provided by three well-known groups realized as automorphism groups of regular rooted trees: ... More
Minimising Unserved Energy Using Heterogeneous Storage UnitsJul 24 2018Feb 23 2019This paper considers the optimal dispatch of energy-constrained heterogeneous storage units to maximise security of supply. A policy, requiring no knowledge of the future, is presented and shown to minimise unserved energy during supply-shortfall events, ... More
Photon propagation and the VHE gamma-ray spectra of blazars: how transparent is really the Universe?Jul 26 2008Nov 23 2008Recent findings by gamma-ray Cherenkov telescopes suggest a higher transparency of the Universe to very-high-energy (VHE) photons than expected from current models of the Extragalactic Background Light. It has been shown that such transparency can be ... More
On fast and slow times in models with diffusionMar 09 2012The linear Kelvin{Voigt operator L_\epsilon is a typical example of wave operator L_0 perturbed by higher-order viscous terms as \epsilonu_xxt. If P\epsilon is a prefixed boundary value problem for L_\epsilon, when \epsilon = 0, L_\epsilon turns into ... More
Study of dynamical supersymmetry breaking for the two dimensional lattice Wess-Zumino modelDec 13 2004A new approach to the study of the transition point in a class of two dimensional Wess-Zumino models is presented. The method is based on the calculation of rigorous lower bounds on the ground state energy density in the infinite lattice limit. Such bounds ... More
Homogeneous isotropic turbulence in dilute polymers: scale by scale budgetAug 09 2002The turbulent energy cascade in dilute polymers solution is addressed here by considering a direct numerical simulation of homogeneous isotropic turbulence of a FENE-P fluid in a triply periodic box. On the basis of the DNS data, a scale by scale analysis ... More
Rare event simulation for stochastic dynamics in continuous timeOct 01 2018Large deviations for additive path functionals and convergence properties for numerical approaches based on population dynamics have attracted recent research interest. The aim of this paper is twofold. Extending results from the literature of particle ... More
Self-Organising Networks for Classification: developing Applications to Science Analysis for Astroparticle PhysicsFeb 09 2004Physics analysis in astroparticle experiments requires the capability of recognizing new phenomena; in order to establish what is new, it is important to develop tools for automatic classification, able to compare the final result with data from different ... More
Evidence synthesis for stochastic epidemic modelsJun 08 2017In recent years the role of epidemic models in informing public health policies has progressively grown. Models have become increasingly realistic and more complex, requiring the use of multiple data sources to estimate all quantities of interest. This ... More
On Path-Complete Lyapunov Functions: Geometry and ComparisonDec 01 2017We study optimization-based criteria for the stability of switching systems, known as Path-Complete Lyapunov Functions, and ask the question "can we decide algorithmically when a criterion is less conservative than another". Our contribution is twofold. ... More
Path-Complete Graphs and Common Lyapunov FunctionsDec 13 2016A Path-Complete Lyapunov Function is an algebraic criterion composed of a finite number of functions, called its pieces, and a directed, labeled graph defining Lyapunov inequalities between these pieces. It provides a stability certificate for discrete-time ... More
ABC in Nuclear ImagingJul 29 2016We consider the application of approximate Bayesian Computation (ABC) in the context of medical imaging data. We consider the parameter estimation of compartmental models in PET imaging analysis, and provide a simple ABC algorithm for its estimation. ... More
Orbit Expandability of Automaton Semigroups and GroupsDec 18 2018We introduce the notion of expandability in the context of automaton semigroups and groups: a word is k-expandable if one can append a suffix to it such that the size of the orbit under the action of the automaton increases by at least k. This definition ... More
Connectedness and isomorphism properties of the zig-zag product of graphsApr 16 2014In this paper we investigate the connectedness and the isomorphism problems for zig-zag products of two graphs. A sufficient condition for the zig-zag product of two graphs to be connected is provided, reducing to the study of the connectedness property ... More
Predicate Pairing for Program VerificationAug 04 2017Jun 27 2018It is well-known that the verification of partial correctness properties of imperative programs can be reduced to the satisfiability problem for constrained Horn clauses (CHCs). However, state-of-the-art solvers for CHCs (CHC solvers) based on predicate ... More
Schreier graphs of the Basilica groupNov 15 2009Apr 29 2010With any self-similar action of a finitely generated group $G$ of automorphisms of a regular rooted tree $T$ can be naturally associated an infinite sequence of finite graphs $\{\Gamma_n\}_{n\geq 1}$, where $\Gamma_n$ is the Schreier graph of the action ... More
Chance-Constrained Ancillary Service Specification for Heterogeneous Storage DevicesApr 06 2019We present a method to find the maximum magnitude of any supply-shortfall service that an aggregator of energy storage devices is able to sell to a grid operator. This is first demonstrated in deterministic settings, then applied to scenarios in which ... More
Towards soliton solutions of a perturbed sine-Gordon equationJul 01 2005Nov 24 2005We give arguments for the existence of {\it exact} travelling-wave (in particular solitonic) solutions of a perturbed sine-Gordon equation on the real line or on the circle, and classify them. The perturbation of the equation consists of a constant forcing ... More
Neutrinos, Cosmic Rays and the MeV BandMar 13 2019The possible association of the blazar TXS 0506+056 with a high-energy neutrino detected by IceCube holds the tantalizing potential to answer three astrophysical questions: 1. Where do high-energy neutrinos originate? 2. Where are cosmic rays produced ... More
Emergent $\text{D}_6$ symmetry in fully-relaxed magic-angle twisted bilayer grapheneSep 28 2018Oct 23 2018We present a tight-binding calculation of a twisted bilayer graphene at magic angle $\theta\sim 1.08^\circ$, allowing for full, in- and out-of-plane, relaxation of the atomic positions. The resulting band structure displays as usual four narrow mini bands ... More
Open Universe for Blazars: a new generation of astronomical products based on 14 years of Swift-XRT dataApr 12 2019Open Universe for blazars is a set of high-transparency data products for blazar science, and the tools designed to generate them. Blazar astrophysics is becoming increasingly data driven, depending on the integration and combined analysis of large quantities ... More
Nonradiative emission and absorption rates of quantum emitters embedded in metallic systems: microscopic description and their determination from electronic transportMay 29 2018We investigate nonradiative emission and absorption rates of two-level quantum emitters embedded in a metal at low temperatures. We obtain the expressions for both nonradiative transition rates and identify a unique, experimentally accessible way to obtain ... More
Neural networks for gamma-hadron separation in MAGICMar 24 2005Neural networks have proved to be versatile and robust for particle separation in many experiments related to particle astrophysics. We apply these techniques to separate gamma rays from hadrons for the MAGIC Cerenkov Telescope. Two types of neural network ... More
Search and analysis of blue straggler stars in open clustersAug 22 2006Aims: This paper presents a new homogeneous catalogue of blue straggler stars (BSS) in Galactic open clusters. Methods: Photometric data for 216 clusters were collected from the literature and 2782 BSS candidates were extracted from 76 of them. Results: ... More
Isospin symmetry breaking at high spins in the mirror pair 67Se and 67AsNov 27 2010Recent experimental data have revealed large mirror energy differences (MED) between high-spin states in the mirror nuclei 67Se and 67As, the heaviest pair where MED have been determined so far. The MED are generally attributed to the isospin symmetry ... More
MultiBUGS: A parallel implementation of the BUGS modelling framework for faster Bayesian inferenceApr 11 2017Nov 29 2018MultiBUGS ( is a new version of the general-purpose Bayesian modelling software BUGS that implements a generic algorithm for parallelising Markov chain Monte Carlo (MCMC) algorithms to speed up posterior inference of Bayesian ... More
Drag Reduction by Polymers in Turbulent Channel Flows: Energy Redistribution Between Invariant Empirical ModesOct 29 2002We address the phenomenon of drag reduction by dilute polymeric additive to turbulent flows, using Direct Numerical Simulations (DNS) of the FENE-P model of viscoelastic flows. It had been amply demonstrated that these model equations reproduce the phenomenon, ... More
Isospin Symmetry violation in mirror E1 transitions: Coherent contributions from the Giant Isovector Monopole Resonance in 67As - 67SeSep 24 2012The assumption of an exact isospin symmetry would imply equal strengths for mirror E1 transitions (at least, in the long-wavelength limit). Actually, large violations of this symmetry rule have been indicated by a number of experimental results, the last ... More
Review of methods for assessing the causal effect of binary interventions from aggregate time-series observational dataApr 20 2018Researchers are often interested in assessing the impact of an intervention on an outcome of interest in situations where the intervention is non-randomised, information is available at an aggregate level, the intervention is only applied to one or few ... More
Conflict Diagnostics in Directed Acyclic Graphs, with Applications in Bayesian Evidence SynthesisOct 02 2013Complex stochastic models represented by directed acyclic graphs (DAGs) are increasingly employed to synthesise multiple, imperfect and disparate sources of evidence, to estimate quantities that are difficult to measure directly. The various data sources ... More
Conflict diagnostics for evidence synthesis in a multiple testing frameworkFeb 23 2017Sep 13 2017Evidence synthesis models that combine multiple datasets of varying design, to estimate quantities that cannot be directly observed, require the formulation of complex probabilistic models that can be expressed as graphical models. An assessment of whether ... More
Estimation of HIV Burden through Bayesian Evidence SynthesisMay 19 2014Planning, implementation and evaluation of public health policies to control the human immunodeficiency virus (HIV) epidemic require regular monitoring of disease burden. This includes the proportion living with HIV, whether diagnosed or not, and the ... More
Plasmon-Assisted Suppression of Surface Trap States and Enhanced Band-Edge Emission in a Bare CdTe Quantum DotMar 08 2019Colloidal quantum dots have emerged as a versatile photoluminescent and optoelectronic material. Issues like fluorescence intermittency, non-radiative Auger recombination and surface traps are commonly addressed by growing a wide-bandgap shell around ... More
Model surgery: joining and splitting models with Markov meldingJul 22 2016Sep 02 2016Analysing multiple evidence sources is often feasible only via a modular approach, with separate submodels specified for smaller components of the available evidence. Here we introduce a generic framework that enables fully Bayesian analysis in this setting. ... More
Sources and fluxes of scale-energy in the overlap layer of wall turbulenceMar 30 2017Direct Numerical Simulations of turbulent channel flows at friction Reynolds number 550, 1000, 1500, are used to analyse the turbulent production, transfer and dissipation mechanisms in the compound space of scales and wall-distances by means of the Kolmogorov ... More
Plasmon-Assisted Suppression of Surface Trap States and Enhanced Band-Edge Emission in a Bare CdTe Quantum DotMar 08 2019Apr 16 2019Colloidal quantum dots have emerged as a versatile photoluminescent and optoelectronic material. Limitations like fluorescence intermittency, non-radiative Auger recombination and surface traps are commonly addressed by growing a wide-bandgap shell. However, ... More
Boundary action of automaton groups without singular points and Wang tilingsApr 26 2016We study automaton groups without singular points, that is, points in the boundary for which the map that associates to each point its stabilizer, is not continuous. This is motivated by the problem of finding examples of infinite bireversible automaton ... More
Joining and splitting models with Markov meldingJul 22 2016Sep 12 2017Analysing multiple evidence sources is often feasible only via a modular approach, with separate submodels specified for smaller components of the available evidence. Here we introduce a generic framework that enables fully Bayesian analysis in this setting. ... More
On the existence of superradiant excitonic states in microtubulesAug 12 2018Microtubules are biological protein polymers with critical and diverse functions. Their structures share some similarities with photosynthetic antenna complexes, particularly in the ordered arrangement of photoactive molecules with large transition dipole ... More
A Homogenous Set of Globular Cluster Relative Distances and ReddeningsAug 25 2004We present distance modulus and reddening determinations for 72 Galactic globular clusters from the homogeneous photometric database of Piotto et al. (2002), calibrated to the HST flight F439W and F555W bands. The distances have been determined by comparison ... More
The Red Giant Branch Luminosity Function BumpAug 25 2003We present observational estimates of the magnitude difference between the luminosity function RGB bump and the HB (Delta(bump-zahb)), and of star counts in the bump region (R_bump), for a sample of 54 Galactic globular clusters (GCs) observed by the ... More
Is our Sun a Singleton?Sep 19 2007Most stars are formed in a cluster or association, where the number density of stars can be high. This means that a large fraction of initially-single stars will undergo close encounters with other stars and/or exchange into binaries. We describe how ... More
Recent results from VHE gamma astrophysics related to fundamental physics and cosmic raysApr 27 2011High-energy photons are a powerful probe for astrophysics and for fundamental physics under extreme conditions. During the recent years, our knowledge of the most violent phenomena in the universe has impressively progressed thanks to the advent of new ... More
GLAST, the Gamma-ray Large Area Space TelescopeSep 18 2000GLAST, a detector for cosmic gamma rays in the range from 20 MeV to 300 GeV, will be launched in space in 2005. Breakthroughs are expected in particular in the study of particle acceleration mechanisms in space and of gamma ray bursts, and maybe on the ... More
A note on the continuity of free-boundaries in finite-horizon optimal stopping problems for one dimensional diffusionsMay 06 2013We provide sufficient conditions for the continuity of the free-boundary in a general class of finite-horizon optimal stopping problems arising for instance in finance and economics. The underlying process is a strong solution of one dimensional, time-homogeneous ... More
On the transition from parabolicity to hyperbolicity for a nonlinear equation under Neumann boundary conditionsOct 21 2018An integro differential equation which is able to describe the evolution of a large class of dissipative models, is considered. By means of an equivalence, the focus shifts to the perturbed sine- Gordon equation that in superconductivity finds interesting ... More
On diffusion effects of the perturbed sine-Gordon equation with Neumann boundary conditionsFeb 29 2016The Neumann boundary problem for the perturbed sine-Gordon equation describing the electrodynamics of Josephson junctions has been considered. The behavior of a viscous term, described by a higher-order derivative with small diffusion coefficient, is ... More
On a parabolic operator of dissipative systemsJul 07 2013A parabolic integro differential operator operator L suitable to describe many phenomena in various physical fields,is considered. By means of equivalence between L and the third order equation which describe the evolution inside an exponentially shaped ... More
On a non linear third - order parabolic equationJul 09 2012Aim of this paper is the qualitative analysis of the solution of a boundary value problem for a third-order non linear parabolic equation which describes several dissipative models. When the source term is linear, the problem is explictly solved by means ... More
(Very)-High-Energy Gamma-Ray Astrophysics: the FutureJan 12 2016Several projects planned or proposed can significantly expand our knowledge of the high-energy Universe in gamma rays. Construction of the Cherenkov telescope array CTA is started, and other detectors are planned which will use the reconstruction of extensive ... More
Hadronic Events at LEPAug 05 2003The hadronic events collected by LEP between 1989 and 2000 have changed dramatically our understanding of QCD, which has now been established as a part of the Standard Model. Still in many sectors (nonperturbative in particular) science analysis needs ... More
Study of Hadronic Decays of the Z Boson at LEPAug 04 2000This report summarizes four recent papers on the characteristics of the hadronic decays of the Z by the LEP collaborations ALEPH, DELPHI and OPAL.
The Stern diatomic sequence via generalized Chebyshev polynomialsNov 08 2015Nov 15 2015Let a(n) be the Stern's diatomic sequence, and let x1,...,xr be the distances between successive 1's in the binary expansion of the (odd) positive integer n. We show that a(n) is obtained by evaluating generalized Chebyshev polynomials when the variables ... More
Domenico Pacini, uncredited pioneer of the discovery of cosmic raysMar 22 2011During a series of experiments performed between 1907 and 1911, Domenico Pacini (Marino 1878-Roma 1934), at that time researcher at the Central Bureau of Meteorology and Geodynamics in Roma, studied the origin of the radiation today called "cosmic rays", ... More
Bo Andersson's contribution to experimental multiparticle production physics: an incomplete and biased selectionFeb 25 2003Among the many topics related to soft QCD in which Bo Andersson gave an important contribution to experiments, this report selects a few for which the final word has not yet been pronounced.
Interconnection Effects in Multiparticle Production from WW Events at LEPMay 07 1998Interactions between the products of the hadronic decays of different Ws in WW pair events can occur at several stages: from the colour rearrangement between the quarks coming from the primary branching, to the gluon exchange during the parton cascade, ... More
The simulation of astroparticle experiments and the GEANT4 toolkitDec 15 2001The new generation of astroparticle experiments will use technologies common to High Energy Physics. Among such technologies a central place is given to the role of simulation.
Fundamental Physics With Cosmic High-Energy Gamma RaysOct 26 2016High-energy photons (above the MeV) are a powerful probe for astrophysics and for fundamental physics under extreme conditions. During the recent years, our knowledge of the high-energy gamma-ray sky has impressively progressed thanks to the advent of ... More
Optimal dividends with partial information and stopping of a degenerate reflecting diffusionMay 30 2018Motivated by the optimal dividend problem, we study a problem of singular stochastic control with partial information on the drift of the underlying process and with absorption. In the Markovian formulation, we have a 2-dimensional degenerate diffusion, ... More
On Adversary Robust Consensus protocols through joint-agent interactionsJan 09 2019A generalized family of Adversary Robust Consensus protocols is proposed and analyzed. These are distributed algorithms for multi-agents systems seeking to agree on a common value of a shared variable, even in the presence of faulty or malicious agents ... More