3 resultados para Differential approach

em Archivo Digital para la Docencia y la Investigación - Repositorio Institucional de la Universidad del País Vasco


Relevância:

60.00% 60.00%

Publicador:

Resumo:

El presente documento hace parte del Proyecto Técnico “Centro de Acogida Inmediata –CAI- para víctimas de violencia de género”, elaborado para la Asociación BETA, Asociación para el Desarrollo de Proyectos de Intervención Social, presentado a la convocatoria del Departamento de Asuntos Sociales y de las Personas Mayores (Nº Expediente 2014//CONASP0148; CÓDIGO CPV: 85311000 Servicios de Asistencia Social con alojamiento).

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This paper presents a model-based approach for reconstructing 3D polyhedral building models from aerial images. The proposed approach exploits some geometric and photometric properties resulting from the perspective projection of planar structures. Data are provided by calibrated aerial images. The novelty of the approach lies in its featurelessness and in its use of direct optimization based on image rawbrightness. The proposed framework avoids feature extraction and matching. The 3D polyhedral model is directly estimated by optimizing an objective function that combines an image-based dissimilarity measure and a gradient score over several aerial images. The optimization process is carried out by the Differential Evolution algorithm. The proposed approach is intended to provide more accurate 3D reconstruction than feature-based approaches. Fast 3D model rectification and updating can take advantage of the proposed method. Several results and evaluations of performance from real and synthetic images show the feasibility and robustness of the proposed approach.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We present a new efficient numerical approach for representing anisotropic physical quantities and/or matrix elements defined on the Fermi surface (FS) of metallic materials. The method introduces a set of numerically calculated generalized orthonormal functions which are the solutions of the Helmholtz equation defined on the FS. Noteworthy, many properties of our proposed basis set are also shared by the FS harmonics introduced by Philip B Allen (1976 Phys. Rev. B 13 1416), proposed to be constructed as polynomials of the cartesian components of the electronic velocity. The main motivation of both approaches is identical, to handle anisotropic problems efficiently. However, in our approach the basis set is defined as the eigenfunctions of a differential operator and several desirable properties are introduced by construction. The method is demonstrated to be very robust in handling problems with any crystal structure or topology of the FS, and the periodicity of the reciprocal space is treated as a boundary condition for our Helmholtz equation. We illustrate the method by analysing the free-electron-like lithium (Li), sodium (Na), copper (Cu), lead (Pb), tungsten (W) and magnesium diboride (MgB2)