Browsing Statistical Physics by Issue Date
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Wildland fire propagation modeling: firespotting parametrisation and energy balance
(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
(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
(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
(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
(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
(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
(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
(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
(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
(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
(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
(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
(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+
(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 ... 
Front Propagation in Random Media
(2019)This PhD thesis deals with the problem of the propagation of fronts under random circumstances. A statistical model to represent the motion of fronts when are evolving in a media characterized by microscopical randomness ... 
Stochastic processes for anomalous diffusion
(2019)Anomalous diffusion is a diffusion process which Mean Square Displacement (MSD) is not a linear funtion of time, what is known as normal diffusion. When the relation is faster than linear, it is called superdiffusion and ... 
On the propagation of nonlinear transients of temperature and pore pressure in a thin porous boundary layer between two rocks.
(2019)The dynamics of transients of fluidrock temperature, pore pressure, pollutants in porous rocks are of vivid interest for fundamental problems in hydrological, volcanic, hydrocarbon systems, deep oil drilling. This can ... 
Surrogatebased uncertainty and sensitivity analysis for bacterial invasion in multispecies biofilm modeling
(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 ... 
Restoring property of the MichelsonSivashinsky equation
(2019)In this paper we propose a derivation of the MichelsonSivashinsky (MS) equation that is based on front propagation only, in opposition to the classical derivation based also on the flow field. Hence, the characteristics ...