In this work I develop numerical algorithms that can be applied directly to differential equations of the general form f (t, x, x') = 0, without the need to cleared x'. My methods are hybrid algorithms between standard methods of solving differential equations and methods of solving algebraic equations, with which the variable x' is numerically cleared. The application of these methods ranges from the ordinary differential equations of order one, to the more general case of systems of m equations of order n. These algorithms are applied to the solution of different physical-mathematical equations. Finally, the corresponding numerical analysis of existence, uniqueness, stability, consistency and convergence is made, mainly for the simplest case of a single ordinary differential equation of the first order.
Abstract
In this work I develop numerical algorithms that can be applied directly to differential equations of the general form f (t, x, x') = 0, without the need to cleared x'. My methods are hybrid algorithms between standard methods of solving differential equations and methods [...]
In this paper we have studied some physical characteristics of gypsum composites incorporated with two different tire rubber granulometry. The experimental program was formed by the following tests: consistency (mini-slump), compressive strength and scanning electron microscopy (SEM). The rubber used in the composites came from the retreading of tires with 5 and 10% incorporation in relation to the plaster mass and the two different granulometry used were denominated thicknesses (# 0.6 mm) and thick (# 1.19 mm ). The results were compared with the control paste, in which there was no incorporation of rubber. The rubbers of different granulometry stood out in different points. The thin rubber presented a compressive strength close to the value observed in the control, with an addition of 5% by mass, which may be due to its adherence to gypsum paste, which occurred in a less porous manner and with a closer interface between the rubber particles and pulp, observed through the SEM. The thick rubber presented the best results in consistency, contributing to the workability of the pulp, which was also observed in SEM, where the thick rubber presents less adherence to the gypsum plaster, compared to the composite with incorporation of fine rubber. It was possible to affirm, then, that rubber as residual material presented interesting characteristics in applications in plaster composites.
Abstract
In this paper we have studied some physical characteristics of gypsum composites incorporated with two different tire rubber granulometry. The experimental program was formed by the following tests: consistency (mini-slump), compressive strength and scanning electron microscopy [...]
Métodos numéricos generales no estándar para la solución directa de ecuaciones diferenciales no despejadas en formas canónicas. 