In recent years a number of methods have been developed for subdividing the surface of the earth to meet the needs of applications in dynamic modeling, survey sampling, and information storage and display. One set of methods uses the surfaces of Platonic solids, or regular polyhedra, as approximations to the surface of the earth. Diamond partitions are similar to recursive subdivisions of the t...

A global model of the atmosphere is presented governed by the shallow water equations and discretized by a Runge–Kutta discontinuous Galerkin method on an unstructured triangular grid. The shallow water equations on the sphere, a two-dimensional surface in R, are locally represented in terms of spherical triangular coordinates, the appropriate local coordinate mappings on triangles. On every tr...

‎In this paper‎, ‎we present an algorithm for generating approximate nondominated points of a multiobjective optimization problem (MOP)‎, ‎where the constraints and the objective functions are convex‎. ‎We provide outer and inner approximations of nondominated points and prove that inner approximations provide a set of approximate weakly nondominated points‎. ‎The proposed algorithm can be appl...

An iterative predictor-corrector technique for the elimination of the approximate factorization errors which result from the factorization of linearized 0-methods in multidimensional reaction~iiffusion equations is proposed, and its convergence and linear stability are analyzed. Four approximate factorization techniques which do not account for the approximate factorization errors are developed...

danehkhoshk anticline is a typical growing anticline in kermanshah province which is located in folded zagros belt. the purpose of this research is to evaluate the effect of tectonic on the triangular facet characteristics, the drainage density and on the drainage pattern formed on anticline. dimensions of triangular facets were determined by means of quickbird satellite images and field works....

This paper presents a comparative analysis of six different iterative power flow methods applied to AC distribution networks, which have been recently reported in the scientific literature. These are (i) successive approximations, (ii) matricial backward/forward method, (iii) triangular-based approach, (iv) product linearization (v) hyperbolic and (vi) diagonal approximation method. The first t...

We consider the numerical solution of the steady-state Navier–Stokes equations with uncertain data. Specifically, we treat the case of uncertain viscosity, which results in a flow with an uncertain Reynolds number. After linearization, we apply a stochastic Galerkin finite element method, combining standard inf-sup stable Taylor–Hood approximation on the spatial domain (on highly stretched grid...

For grid terrain data, we propose a Lepp-surface triangulation method that starts with a coarse initial triangulation of the input data, and incrementally adds data points that reduce the worst edge approximation error in the mesh. The method generalizes a previous Lepp-centroid method in two dimensions as follows: for the edge E, having highest error in the mesh, one or two points close to (on...

Given two polynomials with coeecients over Zk], the associated Bezout matrix B(k) with entries over Zk] deenes a parametric family of Bezout matrices with entries over Z. It is intended in this paper to propose a hybrid approach for determining the inertia of B(k) for any value of k in some real interval. This yields an eecient solution to certain root-location problems for bivariate polynomial...

In this paper, we introduce an extension of Van Leer’s slope limiter for two-dimensional discontinuous Galerkin (DG) methods on arbitrary unstructured quadrangular or triangular grids. The aim is to construct a non-oscillatory shock capturing DG method for the approximation of hyperbolic conservative laws without adding excessive numerical dispersion. Unlike some splitting techniques that are l...