The transient drift di usion model describing the charge transport in semiconductors is con sidered Poisson s equation which is usually used is replaced by Maxwell s equations The di usion and mobility coe cients and the dielectric and magnetic susceptibilities may depend on the space variables Global existence and convergence to the thermal equilibrium is shown

nonlinear model and its inverse of an audio system alessandro loriga Alessandro Loriga: Modello nonlineare di un sistema audio e suo inverso: Non-linear model and its inverse of an audio system, Corso di Laurea Magistrale in Informatica,

In this paper we consider N−phased investment opportunities where the time evolution of the project value follows a jump-di usion process. An explicit valuation formula is derived under two di erent scenarios: in the rst case we consider xed and certain investment costs and in the second case we consider cost uncertainty and assume that investment costs follow a jump-di usion process.

A ®rm's ability to compete in new product markets is vital to its pro®tability and long-term survival. Therefore, it is important to understand the development and growth of these markets. Following a pioneering study by Bass (1969), di€usion models have traditionally provided this understanding in marketing. The great appeal of the Bass model is that it is a simple one that ®ts the data very w...

We consider a nonstationary Markov multiserver queueing model where waiting customers may abandon and subsequently retry. In this paper we derive uid and di usion approximations for the associated waiting time process. The uid and di usion approximations for the corresponding queue length process were obtained in [4] (see also [5]).

The solution of a two dimensional di usion problem with discontinuous coefcients is analyzed on a particular two-regions domain. The solution is shown to contain a singular part, and the particular behavior is quantitatively evaluated. It is well kown that the degree of regularity of the solution for such problem determines the accuracy of the numerical techniques used to approximate the soluti...

This work introduces a generalised hybridisation strategy which utilises the information sharing mechanism deployed in Stochastic Di usion Search when applied to a number of population-based algorithms, e ectively merging this nature-inspired algorithm with some population-based algorithms. The results reported herein demonstrate that the hybrid algorithm, exploiting information-sharing within ...

We derive a cell-centered 3-D di usion di erencing scheme for arbitrary hexahedral meshes using the local support-operators method. Our method is said to be local because it yields a sparse matrix representation for the di usion equation, whereas the traditional support-operators method yields a dense matrix representation. The di usion discretization scheme that we have developed o ers several...

We compare two load balancing techniques for Cayley graphs based on information and load exchange between neighboring vertices. In the rst scheme, called natural di usion, each vertex gives (or receives) a xed part of the load di erence to (from) its direct neighbors. In the second scheme, called Cayley di usion, each vertex successively gives (or receives) a part of the load di erence to (or f...

The article is concerned with eÆcient edge-preserving numerical techniques for noise removal via anisotropic di usion. New minimum-biased (MB) nite di erence formulas are introduced to minimize di usion on both the piecewise smooth portions and their boundaries. Locally one-dimensional time-stepping algorithms are analyzed and a formula for eÆcient timestep sizes is suggested, to remove the hig...