Now showing items 26-42 of 42

    • Quasi-probability Approach for Modelling Local Extinction and Counter-gradient in Turbulent Premixed Combustion 

      Pagnini G.; Trucchia A. (Proceedings/Extended Abstract Book (6 pages) of the XLI Meeting of the Italian Section of the Combustion Institute, 2018-05-23)
      In opposition to standard probability distributions, quasi-probability distributions can have negative values which highlight nonclassical properties of the corresponding system. In quantum mechanics, such negative values ...
    • Random diffusivity from stochastic equations: comparison of two models for Brownian yet non-Gaussian diffusion 

      Sposini V.; Chechkin A. V.; Seno F.; Pagnini G.; Metzler R. (New Journal of Physics, 2018-04)
      A considerable number of systems have recently been reported in which Brownian yet non-Gaussian dynamics was observed. These are processes characterised by a linear growth in time of the mean squared displacement, yet the ...
    • RandomFront 2.3 A physical parametrisation of fire-spotting for operational fire spread models: Implementation in WRF-Sfire and response analysis with LSFire+ 

      Trucchia A.; Egorova V.; Butenko A.; Kaur I.; Pagnini G. (Geoscientific Model Development, 2018-12)
      Fire-spotting is often responsible for a dangerous flare up in the wildfire and causes secondary ignitions isolated from the primary fire zone leading to perilous situations. The main aim of the present research to provide ...
    • The role of the environment in front propagation 

      Trucchia A.; Pagnini G. (Proceedings of the 18th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2018 July 9–14, 2018, 2018-07-09)
      In this work we study the role of a complex environment in the propagation of a front with curvature-dependent speed. The motion of the front is split into a drifting part and a fluctuating part. The drifting part is ...
    • Scaling law of diffusivity generated by a noisy telegraph signal with fractal intermittency 

      Paradisi P.; Allegrini P. (Chaos, Solitons and Fractals, 2015-12-31)
      In many complex systems the non-linear cooperative dynamics determine the emergence of self-organized, metastable, structures that are associated with a birth-death process of cooperation. This is found to be described by ...
    • Self-similar stochastic models with stationary increments for symmetric space-time fractional diffusion 

      Pagnini G. (MESA 2014 - 10th IEEE/ASME International Conference on Mechatronic and Embedded Systems and Applications, Conference Proceedings, 2014-12-31)
      An approach to develop stochastic models for studying anomalous diffusion is proposed. In particular, in this approach the stochastic particle trajectory is based on the fractional Brownian motion but, for any realization, ...
    • Short note on the emergence of fractional kinetics 

      Pagnini G. (Physica A: Statistical Mechanics and its Applications, 2014-12-31)
      In the present Short Note an idea is proposed to explain the emergence and the observation of processes in complex media that are driven by fractional non-Markovian master equations. Particle trajectories are assumed to ...
    • Stochastic spatial models in ecology: a statistical physics approach 

      Pigolotti S.; Cencini M.; Molina-Garcia D.; Muñoz M.A. (Journal of Statistical Physics, 2017-11-21)
      Ecosystems display a complex spatial organization. Ecologists have long tried to characterize them by looking at how different measures of biodiversity change across spatial scales. Ecological neutral theory has provided ...
    • Surrogate-based uncertainty and sensitivity analysis for bacterial invasion in multi-species biofilm modeling 

      Trucchia A.; Mattei M.R.; Luongo V.; Frunzo L.; Rochoux M.C. (Communications Nonlinear Sciences and Numerical Simulation, 2019)
      In this work, we present a probabilistic analysis of a detailed one-dimensional biofilm model that explicitly accounts for planktonic bacterial invasion in a multi-species biofilm. The objective is (1) to quantify and ...
    • The emergence of self-organization in complex systems-Preface 

      Paradisi P.; Kaniadakis G.; Scarfone A.M. (Chaos, Solitons and Fractals, 2015-12-31)
      [No abstract available]
    • The M-Wright function as a generalization of the Gaussian density for fractional diffusion processes 

      Pagnini G. (Fractional Calculus and Applied Analysis, 2013-12-31)
      The leading role of a special function of the Wright-type, referred to as M-Wright or Mainardi function, within a parametric class of self-similar stochastic processes with stationary increments, is surveyed. This class ...
    • Turbulence and fire-spotting effects into wild-land fire simulators 

      Kaur I.; Mentrelli A.; Bosseur F.; Filippi J.-B.; Pagnini G. (Communications in Nonlinear Science and Numerical Simulation, 2016-01-01)
      This paper presents a mathematical approach to model the effects and the role of phenomena with random nature such as turbulence and fire-spotting into the existing wildfire simulators. The formulation proposes that the ...
    • Two-particle anomalous diffusion: Probability density functions and self-similar stochastic processes 

      Pagnini G.; Mura A.; Mainardi F. (Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2013-12-31)
      Two-particle dispersion is investigated in the context of anomalous diffusion. Two different modeling approaches related to time subordination are considered and unified in the framework of self-similar stochastic processes. ...
    • Velocity and energy distributions in microcanonical ensembles of hard spheres 

      Scalas E.; Gabriel A.T.; Martin E.; Germano G. (Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 2015-12-31)
      In a microcanonical ensemble (constant NVE, hard reflecting walls) and in a molecular dynamics ensemble (constant NVEPG, periodic boundary conditions) with a number N of smooth elastic hard spheres in a d-dimensional volume ...
    • Wildfire propagation modelling 

      Pagnini G.; Egorova V.; Trucchia A.; Mentrelli A.; Kaur I. (Geophysical Research Abstracts Vol. 20, 2018)
      Wildfires are a concrete problem with a strong impact on human life, property and the environment, because they cause disruption and are an important source of pollutants. Climate change and ...
    • Wildland fire propagation modeling: fire-spotting parametrisation and energy balance 

      Egorova V. N.; Pagnini G.; Trucchia A. (Proceedings of the 17th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2017, pp. 805 - 813, 2017-07-04)
      Present research concerns the physical background of a wild-fire propagation model based on the split of the front motion into two parts - drifting and fluctuating. The drifting part is solved by the level set method and ...
    • Wildland fire propagation modelling 

      Egorova V. N.; Pagnini G.; Trucchia A. (MODELLING FOR ENGINEERING AND HUMAN BEHAVIOUR 2017 Extended abstract, 2017-12)
      Wildfire propagation modelling is a challenging problem due to its complex multi-scale multi-physics nature. This process can be described by a reaction- diffusion equation based on the energy balance principle. Alternative ...