RESUMEN
We present (geometric) multigrid methods for isogeometric discretization of scalar second order elliptic problems. The smoothing property of the relaxation method, and the approximation property of the intergrid transfer operators are analyzed. These properties, when used in the framework of classical multigrid theory, imply uniform convergence of two-grid and multigrid methods. Supporting numerical results are provided for the smoothing property, the approximation property, convergence factor and iterations count for V-, W- and F-cycles, and the linear dependence of V-cycle convergence on the smoothing steps. For two dimensions, numerical results include the problems with variable coefficients, simple multi-patch geometry, a quarter annulus, and the dependence of convergence behavior on refinement levels [Formula: see text], whereas for three dimensions, only the constant coefficient problem in a unit cube is considered. The numerical results are complete up to polynomial order [Formula: see text], and for [Formula: see text] and [Formula: see text] smoothness.
RESUMEN
Tumor resection and trauma may leave devastating defects in the head and neck area complicating and preventing patient rehabilitation; therefore, plastic surgery methods are required which are able to prevent further complications and provide efficient functional and aesthetic reconstruction. In this review article typical cases and the interdisciplinary management of plastic surgery are presented.
Asunto(s)
Traumatismos Craneocerebrales/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Procedimientos de Cirugía Plástica/métodos , Complicaciones Posoperatorias/cirugía , Cráneo/lesiones , Cráneo/cirugía , Traumatismos de los Tejidos Blandos/cirugía , Neoplasias de los Tejidos Blandos/cirugía , Conducta Cooperativa , Humanos , Comunicación Interdisciplinaria , Microcirugia/métodos , Reoperación , Colgajos Quirúrgicos/cirugíaRESUMEN
A modified implantable pulse generator (MIPG) for intraoperative test stimulation in chronic deep brain stimulation is described. The MIPG can be used for bipolar stimulation with quadripolar electrodes. The device is programmed and controlled with a standard console programmer. It can also be used for postoperative test stimulation with externalized electrodes. In our experience, the MIPG has several advantages as compared to the screener that is usually used.