88,657 research outputs found
Convergence Analysis of High Order Algebraic Fractional Step Schemes for Time-Dependent Stokes Equations.
No full textIn this paper we analyze the family of Yosida algebraic fractional step schemes proposed in [A. Quarteroni, F. Saleri, and A. Veneziani, Comput. Methods Appl. Mech. Engrg., 188 (2000), pp. 505–526], [F. Saleri and A. Veneziani, SIAM J. Numer. Anal., 43 (2005), pp. 174–194], and [P. Gervasio, F. Saleri, and A. Veneziani, J. Comput. Phys., 214 (2006), pp. 347–365] when applied to time-dependent Stokes equations. Under suitable regularity assumptions on the data, splitting error estimates both for velocity and pressure are established. In particular we analyze the first three methods of this family, providing, respectively, convergence (of the fractional step solution towards the numerical solution achieved without any operator splitting) of orders 3/2, 5/2, 7/2 for the velocity and 1, 2, 3 for the pressure. Moreover a general way to set up higher-order schemes is proposed. The present analysis is carried out when spectral element methods are employed for space discretization
Exploring complex protein-ligand recognition mechanisms with coarse metadynamics
No full textThe metadynamics method has been shown to be a valuable tool to study the mechanism of molecular recognition in atomistic detail [Gervasio, F. L.; et al. J. Am. Chem. Soc. 2005, 127, 2600]. However, it requires an a priori knowledge of all slow degrees of freedom relevant to the docking/undocking mechanism. Here we investigate a combination of docking/clustering with metadynamics performed with a subset of the necessary degrees of freedom (coarse metadynamics), and show that it provides a full mechanistic insight on the protein-ligand docking mechanism. Moreover, the proposed protocol is able to clearly distinguish between crystallographic and noncrystallographic poses of protein-ligand complexes, and also to find the transition state of the full undocking mechanism, thus giving an indication on the binding free energy
Algebraic fractional-step schemes with spectral methods for the incompressible Navier-Stokes equations
No full textThe numerical investigation of a recent family of algebraic fractional-step methods for the solution of the incompressible
time-dependent Navier–Stokes equations is presented. These methods are improved versions of the Yosida
method proposed in [A. Quarteroni, F. Saleri, A. Veneziani, Factorization methods for the numerical approximation
of Navier–Stokes equations Comput. Methods Appl. Mech. Engrg. 188(1–3) (2000) 505–526; A. Quarteroni, F. Saleri,
A. Veneziani, J. Math. Pures Appl. (9), 78(5) (1999) 473–503] and one of them (the Yosida4 method) is proposed in this
paper for the first time. They rely on an approximate LU block factorization of the matrix obtained after the discretization
in time and space of the Navier–Stokes system, yielding a splitting in the velocity and pressure computation. In
this paper, we analyze the numerical performances of these schemes when the space discretization is carried out with a
spectral element method, with the aim of investigating the impact of the splitting on the global accuracy of the
computation
Algebraic fractional-step schemes for time-dependent incompressible Navier-Stokes equations.
No full textThe numerical investigation of a recent family of algebraic fractional-step methods (the so called Yosida methods) for the solution of the incompressible time-dependent Navier–Stokes equations is presented. A comparison with the Karniadakis–Israeli–Orszag method Karniadakis et al. (1991, J. Comput. Phys. 97, 414–443) is carried out. The high accuracy in time of these schemes well combines with the high accuracy in space of spectral methods
Scrivere la guerra. Corso avanzato di Lingua e cultura araba per lauree specialistiche (units 1-6, 9-10, 20; 19.3, 19.4, 19.5)
No full textIl volume mette a disposizione degli studenti di lauree magistrali i risultati delle ricerche degli autori su questioni letterarie, sociali e politiche relative al mondo arabo contemporane
TERMOCRONO. Un semplice sistema economico e flessibile per misure di temperatura in tempo reale
No full textIl ruolo del marketing del territorio per una migliore valorizzazione qualitativa dei prodotti agro-alimnetari
No full text
Methematical Bioeconomic Modelling in the Interaction between Aquaculture and Open-Sea Fisheries
No full text- …
