Now showing items 21-30 of 265
Numerical Techniques for the Treatment of Quasistatic Solid Viscoelastic Stress Problems
For quasistatic stress problems two alternative constitutive relationships expressing the stress in a linear viscoelastic solid body as a linear functional of the strain are derived. In conjunction with the equations of ...
On the Formulation of the Primal-Dual Newton Interior-Point Method for Nonlinear Programming
In this work we first study in detail the formulation of the primal-dual interior-point method for linear programming. We show that, contrary to popular belief, it cannot be viewed as the damped Newton's method applied to ...
On Alternative Problem Formulations for Multidisciplinary Design Optimization
In this paper we introduce a perspective on multidisciplinary design optimization (MDO) problem formulation that provides a basis for choosing among existing formulations and suggests provocative, new ones. MDO problems ...
On the Quadratic Convergence of the Simplified Mizuno-Todd-Ye Algorithm for Linear Programming
It is known that the Mizuno-Todd-Ye predictor-corrector primal-dual Newton interior-point method generates a duality gap sequence which converges quadratically to zero, and this is accomplished with an iteration complexity ...
On the Convergence of the Mizuno-Todd-Ye Algorithm to the Analytic Center of the Solution Set
In this work we demonstrate that the Mizuno-Todd-Ye predictor corrector primal-dual interior-point method for linear programming generates iteration sequences that converge to the analytic center of the solution set.
Schwarz Methods with Local Refinement for the p-Version Finite Element Method
We study local refinement for an additive Schwarz method with overlap using the p-version finite element method, introduced in a previous paper. We consider linear, scalar, self-adjoint, second order elliptic problems and ...
C++ and Fortran 77 Timing Comparisons
Recently there has been considerable debate within the scientific computation community over the suitability of C++ for large scale numerical computation. This note reports on timing studies of Fortran 77 and C++ conducted ...
On the Quadratic Convergence of the Singular Newton's Method
The purpose of this essay is to describe a situation that we have found particularly exciting in our recent work in interior-point methods for linear programming. To our surprise, we have seen considerable theory developed ...
Sizing the BFGS and DFP Updates: A Numerical Study
In this study we develop and test a strategy for selectively sizing (multiplying by an appropriate scalar) the approximate Hessian matrix before it is updated in the BFGS and DFP trust-region methods for unconstrained ...
Simulation of Flow in Root-Soil Systems
In this paper we develop a mathematical model of a root-soil system, and also accurate and efficient finite element and finite difference algorithms for approximating this model. The goal of our work is to develop an ...