A modern approach to the evolution of a mixed (stars and gas) self–gravitating system is the fully Lagrangian particle approach. The gaseous (particle) phase differs from the compact because the mutual force is given by the sum of gravity and pressure gradient. In this note we report of some characteristics, advantages and limitations of this approach for what regards the evaluation of forces i...

This work presents a new Fast Multipole Method (FMM) based on plane wave expansions (PWFMM), combining the advantages of the low and high frequency formulations. We revisit the method of Greengard et al. [1] devoted to the low frequency regime and based on the splitting of the Green’s function into a propagative and an evanescent part. More precisely, we give an explicit formula of the filtered...

There has been a large increase in the amount of work on hierarchical lowrank approximation methods, where the interest is shared by multiple communities that previously did not intersect. This objective of this article is two-fold; to provide a thorough review of the recent advancements in this field from both analytical and algebraic perspectives, and to present a comparative benchmark of two...

Ab initio fully differential cross-sections for electron scattering in liquid xenon are developed from a solution of the Dirac–Fock scattering equations, using a recently developed framework (Boyle et al 2015 J. Chem. Phys. 142 154507) which considers multipole polarizabilities, a non-local treatment of exchange, and screening and coherent scattering effects. A multi-term solution of Boltzmann’...

The Coupled Dipole method, as originally formulated by Purcell and Pennypacker, is a very powerful method to simulate the Elastic Light Scattering from arbitrary particles. This method however has one major drawback: if the size of the particles grows, or if scattering from an ensemble of randomly oriented particles has to be simulated, the computational demands of the Coupled Dipole method soo...

In this paper, we present a real-time face detection method based on hybrid neural networks. We propose a modified version of fuzzy min-max (FMM) neural network for feature analysis and face classification. A relevance factor between features and pattern classes is defined to analyze the saliency of features. The measure can be utilized for the feature selection to construct an adaptive skin-co...

In this letter we describe the pseudoparticle multipole method (PM), a new method to express multipole expansion by a distribution of pseudoparticles. We can use this distribution of particles to calculate high order terms in both the Barnes-Hut treecode and FMM. The primary advantage of PM is that it works on GRAPE. GRAPE is a special-purpose hardware for the calculation of gravitational force...

Solution of periodic boundary value problems is of interest in various branches of science and engineering such as optics, electromagnetics and mechanics. In our previous studies we have developed a periodic Fast Multipole Method (FMM) as a fast solver of wave problems in periodic domains. It has been found, however, that the convergence of the iterative solvers for linear equations slows down ...

Fast-multipole and precorrected-FFT accelerated iterative methods have substantially improved the eeciency of Method-of-Moments (MOM) based 3-D electromagnetic analysis programs. In this paper we present a novel second-kind integral formulation and discretization approach for electrostatic analysis, as well as a projection technique for electroquasistatic analysis. We show that when these new a...