Browsing Statistical Physics by Issue Date
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Wildland fire propagation modeling: firespotting parametrisation and energy balance
(Proceedings of the 17th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2017, pp. 805  813, 20170704)Present research concerns the physical background of a wildfire 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 ... 
Stochastic spatial models in ecology: a statistical physics approach
(Journal of Statistical Physics, 20171121)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 ... 
Wildland fire propagation modelling
(MODELLING FOR ENGINEERING AND HUMAN BEHAVIOUR 2017 Extended abstract, 201712)Wildfire propagation modelling is a challenging problem due to its complex multiscale multiphysics nature. This process can be described by a reaction diffusion equation based on the energy balance principle. Alternative ... 
Concurent multiscale physical parametrization of firespotting: A study on the role of macro and mesoscale characteristics of the system
(Advances in Forest Fire Research, 2018)The strong impact of wildfires in terms of lives and homes lost and of damage to ecosystems, calls for an urgent improvement in the risk management. The aim of the present research is the improvement of these software ... 
Wildfire propagation modelling
(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 ... 
Random diffusivity from stochastic equations: comparison of two models for Brownian yet nonGaussian diffusion
(New Journal of Physics, 201804)A considerable number of systems have recently been reported in which Brownian yet nonGaussian dynamics was observed. These are processes characterised by a linear growth in time of the mean squared displacement, yet the ... 
Effective selfsimilar expansion for the GrossPitaevskii equation
(Physical Review A, 201804)We consider an effective scaling approach for the free expansion of a onedimensional quantum wave packet, consisting in a selfsimilar evolution to be satisfied on average, i.e., by integrating over the coordinates. A ... 
Modeling of birthdeath and diffusion processes in biological complex environments
(20180420)This thesis is centered on the theory of stochastic processes and their applications in biological systems characterized by a complex environment. Three case studies have been modeled by the use of the three fundamental ... 
Quasiprobability Approach for Modelling Local Extinction and Countergradient in Turbulent Premixed Combustion
(Proceedings/Extended Abstract Book (6 pages) of the XLI Meeting of the Italian Section of the Combustion Institute, 20180523)In opposition to standard probability distributions, quasiprobability distributions can have negative values which highlight nonclassical properties of the corresponding system. In quantum mechanics, such negative values ... 
The role of the environment in front propagation
(Proceedings of the 18th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2018 July 9–14, 2018, 20180709)In this work we study the role of a complex environment in the propagation of a front with curvaturedependent speed. The motion of the front is split into a drifting part and a fluctuating part. The drifting part is ... 
Langevin equation in complex media and anomalous diffusion
(Journal of the Royal Society Interface, 20180730)The problem of biological motion is a very intriguing and topical issue. Many efforts are being focused on the development of novel modelling approaches for the description of anomalous diffusion in biological systems, such ... 
Crossover from anomalous to normal diffusion: truncated powerlaw noise correlations and applications to dynamics in lipid bilayers
(New Journal of Physics, 20181018)The emerging diffusive dynamics in many complex systems shows a characteristic crossover behaviour from anomalous to normal diffusion which is otherwise fitted by two independent powerlaws. A prominent example for a ... 
Centreofmass like superposition of OrnsteinUhlenbeck processes: A pathway to nonautonomous stochastic differential equations and to fractional diffusion
(Fractional Calculus and Applied Analysis, 20181025)We consider an ensemble of Ornstein–Uhlenbeck processes featuring a population of relaxation times and a population of noise amplitudes that characterize the heterogeneity of the ensemble. We show that the centreofmass ... 
Modeling anomalous heat diffusion: Comparing fractional derivative and nonlinear diffusivity treatments
(International Journal of Thermal Sciences, 201811)In the Fourier heat conduction equation, when the flux definition is expressed as the product of a constant diffusivity and the temperature gradient, the characteristic length scale evolves as the square root of time. ... 
RandomFront 2.3 A physical parametrisation of firespotting for operational fire spread models: Implementation in WRFSfire and response analysis with LSFire+
(Geoscientific Model Development, 201812)Firespotting 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 ... 
Surrogatebased uncertainty and sensitivity analysis for bacterial invasion in multispecies biofilm modeling
(Communications Nonlinear Sciences and Numerical Simulation, 2019)In this work, we present a probabilistic analysis of a detailed onedimensional biofilm model that explicitly accounts for planktonic bacterial invasion in a multispecies biofilm. The objective is (1) to quantify and ... 
Fractional kinetics in random/complex media
(Handbook of Fractional Calculus with Applications Volume 5 Applications in Physics, Part B, 2019)In this chapter, we consider a randomlyscaled Gaussian process and discuss a number of applications to model fractional diffusion. Actually, this approach can be understood as a Gaussian diffusion in a medium characterized ... 
Modeling nonstationarities in highfrequency financial time series
(Physica A: Statistical Mechanics and its Applications, 201901)We study tickbytick financial returns for the FTSE MIB index of the Italian Stock Exchange (Borsa Italiana). We confirm previously detected nonstationarities. Scaling properties reported before for other highfrequency ... 
On the merits of sparse surrogates for global sensitivity analysis of multiscale nonlinear problems: Application to turbulence and firespotting model in wildland fire simulators
(Communications in Nonlinear Science and Numerical Simulation, 201902)Many nonlinear phenomena, whose numerical simulation is not straightforward, depend on a set of parameters in a way which is not easy to predict beforehand. Wildland fires in presence of strong winds fall into this category, ... 
Firespotting generated fires. Part I: The role of atmospheric stability
(Applied Mathematical Modelling, 201902)This is the first part of two papers concerning firespotting generated fires. In this part we deal with the impact of macroscale factors, such as the atmospheric stability, and in the second part we deal with mesoscale ...