Browsing Statistical Physics by Title
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Gaussian processes in complex media: new vistas on anomalous diffusion
(201909)Normal or Brownian diffusion is historically identified by the linear growth in time of the variance and by a Gaussian shape of the displacement distribution. Processes departing from the at least one of the above conditions ... 
A generalized Stefan model accounting for system memory and nonlocality
(202005)The Stefan problem, involving the tracking of an evolving phasechange front, is the prototypical example of a moving boundary problem. In basic one dimensional problems it is well known that the front advances as the ... 
Gut microbiota ecology: Biodiversity estimated from hybrid neutralniche model increases with health status and aging
(20201030)In this work we propose an index to estimate the gut microbiota biodiversity using a modeling approach with the aim of describing its relationship with health and aging. The gut microbiota, a complex ecosystem that links ... 
A hypothesis about parallelism vs. seriality in dreams
(20191010)The current article discusses the hypothesis about parallelism vs. Seriality in dreams. The process of dream building implies the construction of a complex network of closely interrelated sources. On the other hand, the ... 
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 ... 
The MWright function as a generalization of the Gaussian density for fractional diffusion processes
(20131231)The leading role of a special function of the Wrighttype, referred to as MWright or Mainardi function, within a parametric class of selfsimilar stochastic processes with stationary increments, is surveyed. This class ... 
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. ... 
Modeling nonstationarities in highfrequency financial time series
(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 ... 
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 ... 
Modelling and simulation of wildland fire in the framework of the level set method
(20160101)Among the modelling approaches that have been proposed for the simulation of wildfire propagation, two have gained considerable attention in recent years: the one based on a reactiondiffusion equation, and the one based ... 
Modelling wildland fire propagation by tracking random fronts
(20141231)Abstract. Wildland fire propagation is studied in the liter ature by two alternative approaches, namely the reaction– diffusion equation and the levelset method. These two ap proaches are considered alternatives to each ... 
Numerical valuation of twoasset options under jump diffusion models using GaussHermite quadrature
(20170419)In this work a finite difference approach together with a bivariate Gauss–Hermite quadrature technique is developed for partial integrodifferential equations related to option pricing problems on two underlying asset ... 
On the merits of sparse surrogates for global sensitivity analysis of multiscale nonlinear problems: Application to turbulence and firespotting model in wildland fire simulators
(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, ... 
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 ... 
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 random diffusivity approach for diffusion in heterogeneous systems
(20201216)The two hallmark features of Brownian motion are the linear growth $\langle x^2(t) \rangle = 2 D d t$ of the mean squared displacement (MSD) with diffusion coefficient $D$ in $d$ spatial dimensions, and the Gaussian ... 
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 ... 
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 ... 
Reduced description method in the kinetic theory of Brownian motion with active fluctuations
(20190901)We develop a microscopic approach to the kinetic theory of manyparticle systems with dissipative and potential interactions in presence of active fluctuations. The approach is based on a generalization of Bogolyubov–Peletminskii ... 
A renewal model for the emergence of anomalous solute crowding in liposomes
(20151231)A fundamental evolutionary step in the onset of living cells is thought to be the spontaneous formation of lipid vesicles (liposomes) in the prebiotic mixture. Even though it is well known that hydrophobic forces drive ...