Now showing items 120-139 of 204

• #### Necking in 2D incompressible polyconvex materials: theoretical framework and numerical simulations ﻿

(2017-06-15)
We show examples of 2D incompressible isotropic homogeneous hyperelastic materials with a poly-convex stored-energy function that present necking. The construction of the stored-energy function of amaterial satisfying all ...
• #### A new acoustic assumption for orthorhombic media ﻿

(2020-11)
In exploration seismology, the acquisition, processing and inversion of P-wave data is a routine. However, in orthorhombic anisotropic media, the governing equations that describe the P-wave propagation are coupled with ...
• #### New post processing method for interpretation of through casing resistivity (TCR) measurements ﻿

(2011-03)
We propose a new iterative method for post processing through casing resistivity (TCR) measurements. This method can be seen as a correction or extension of Kaufman´s theory to more complex scenarios, in which the casing ...
• #### Non-conforming curved finite element schemes for time-dependent elastic-acoustic coupled problems ﻿

(2016-01-01)
High-order numerical methods for solving time-dependent acoustic-elastic coupled problems are introduced. These methods, based on Finite Element techniques, allow for a flexible coupling between the fluid and the solid ...
• #### Nonhyperbolic normal moveout stretch correction with deep learning automation ﻿

(2022-02-15)
Normal-moveout (NMO) correction is a fundamental step in seismic data processing. It consists of mapping seismic data from recorded traveltimes to corresponding zero-offset times. This process produces wavelet stretching ...
• #### Nonobtuse local tetrahedral refinements towards a polygonal face/interface ﻿

(2011-12-31)
In this note we show how to generate and conformally refine nonobtuse tetrahedral meshes locally in the neighbourhood of a polygonal face or a polygonal interior interface of a three-dimensional domain. The technique ...
• #### A Numerical 1.5D Method for the Rapid Simulation of Geophysical Resistivity Measurements ﻿

(2018-06-14)
In some geological formations, borehole resistivity measurements can be simulated using a sequence of 1D models. By considering a 1D layered media, we can reduce the dimensionality of the problem from 3D to 1.5D via a ...
• #### Numerical Investigation of Wet Inflow in Steam Turbine Cascades Using NURBS-based Mesh Generation Method ﻿

(2020)
In this paper, the impact of existence of wetness in the inflow of stationary cascades of steam turbine blades has been numerically investigated. A new mesh generation method based on non-uniform rational B-splines (NURBS) ...
• #### Offsets and front tire tracks to projective hedgehogs ﻿

(2022-07-25)
There are some known properties on curves of constant width and Zindler curves and their relationship with offsets and front tire-track curves in convex geometry. In this work, a generalization of all these concepts and ...
• #### On Conforming Tetrahedralisations of Prismatic Partitions ﻿

(2013-12-31)
We present an algorithm for conform (face-to-face) subdividing prismatic partitions into tetrahedra. This algorithm can be used in the finite element calculations and analysis.
• #### On continuous and discrete maximum principles for elliptic problems with the third boundary condition ﻿

(2013-12-31)
In this work, we present and discuss some continuous and discrete maximum principles for linear elliptic problems of the second order with the third boundary condition (almost never addressed to in the available literature ...
• #### On global and local mesh refinements by a generalized conforming bisection algorithm ﻿

(2010-12-31)
We examine a generalized conforming bisection (GCB-)algorithm which allows both global and local nested refinements of the triangulations without generating hanging nodes. It is based on the notion of a mesh density function ...
• #### On initialization of milling paths for 5-axis flank CNC machining of free-form surfaces with general milling tools ﻿

(2019-03-27)
We propose a path-planning algorithm for 5-axis flank CNC machining with general tools of varying curvature. Our approach generalizes the initialization strategy introduced for conical tools [Bo et al., 2017] to arbitrary ...
• #### On isoptics and isochordal-viewed curves ﻿

(2021)
In this paper, some results involving isoptic curves and constant $\phi$-width curves are given for any closed curve. The non-convex case, as well as non-simple shapes with or without cusps are considered. Relating the ...
• #### On modifications of continuous and discrete maximum principles for reaction-diffusion problems ﻿

(2011-12-31)
In this work, we present and discuss some modifications, in the form of two-sided estimation (and also for arbitrary source functions instead of usual sign-conditions), of continuous and discrete maximum principles for the ...
• #### On nonobtuse refinements of tetrahedral finite element meshes ﻿

(2014-12-31)
It is known that piecewise linear continuous finite element (FE) approximations on nonobtuse tetrahedral FE meshes guarantee the validity of discrete analogues of various maximum principles for a wide class of elliptic ...
• #### On numerical quadrature for $C^1$ quadratic Powell-Sabin 6-split macro-triangles ﻿

(2018-08-01)
The quadrature rule of Hammer and Stroud [16] for cubic polynomials has been shown to be exact for a larger space of functions, namely the $C^1$ cubic Clough-Tocher spline space over a macro-triangle if and only if the ...
• #### On numerical regularity of the face-to-face longest-edge bisection algorithm for tetrahedral partitions ﻿

(2014-12-31)
The finite element method usually requires regular or strongly regular families of partitions in order to get guaranteed a priori or a posteriori error estimates. In this paper we examine the recently invented longest-edge ...
• #### On numerical solution of Fredholm and Hammerstein integral equations via Nystr\"{o}m method and Gaussian quadrature rules for splines ﻿

(2022-01)
Nystr\"{o}m method is a standard numerical technique to solve Fredholm integral equations of the second kind where the integration of the kernel is approximated using a quadrature formula. Traditionally, the quadrature ...
• #### On quadrature rules for solving Partial Differential Equations using Neural Networks ﻿

(2022-04-01)
Neural Networks have been widely used to solve Partial Differential Equations. These methods require to approximate definite integrals using quadrature rules. Here, we illustrate via 1D numerical examples the quadrature ...