SDS2 is a system to discover and identify the quantitative model consisting of simultaneous equations re ecting the rst principles underlying the objective process through experiments. It consists of SSF and SDS, where the former is to discover the structure of the simultaneous equations and the latter to discover a quantitative formula of each complete equation. The power of SDS2 comes from th...

This paper treats the stress distribution in an ellipsoidal shell of revolution with a hole. The problem is reduced to the solution of sets of eight simultaneous equations. If interest is restricted to the neighborhood of the hole, a simplification occurs requiring the solution of sets of four simultaneous equations.

abstract export of nonoil goods in economic activities is so important and its effect on economic and comparative growth is undeniable. so, emphasize on agricultural sector and development of export in this sector prepares good conditions, for iran, to be present at international markets relying its advantages. the study tries to recognize necessary policies to enhance agricultural export poten...

In this paper, we consider singular and degenerate parabolic equations$$u_t =(x^alpha u_x)_x +u^m (x_0,t)v^{n} (x_0,t),quadv_t =(x^beta v_x)_x +u^q (x_0,t)v^{p} (x_0,t),$$ in $(0,a)times (0,T)$, subject to nullDirichlet boundary conditions, where $m,n, p,qge 0$, $alpha, betain [0,2)$ and $x_0in (0,a)$. The optimal classification of non-simultaneous and simultaneous blow-up solutions is determin...