Let P be a finite classical polar space of rank d . An m -regular system with respect to ( k − 1 ) -dimensional projective spaces , ≤ is set R generators the property that every lies on exactly Regular systems are investigated. Some non-existence results about certain 1-regular low proved and procedure obtain ′ from given described. Finally, three different construction methods regular w.r.t. p...

A subset $S$ of vertex set $V(D)$ is an {em indpendent dominating set} of $D$ if $S$ is both an independent and a dominating set of $D$. The {em indpendent domination number}, $i(D)$ is the cardinality of the smallest independent dominating set of $D$. In this paper we calculate the independent domination number of the { em cartesian product} of two {em directed paths} $P_m$ and $P_n$ for arbi...

[1] The record of recent climate change on Mars is encoded in the polar layered deposits within the north polar cap. Individual Mars Orbiter Camera (MOC) images of exposed layer sequences in cliffs and troughs provide the equivalent of high resolution ‘‘cores’’ through many sections in the upper part of the north polar layered terrain. In order to decode this record it is necessary 1) to quanti...

We present a big-M method for solving general linear programming problems with a recently developed exterior point simplex algorithm (EPSA). We also provide intuitive motivations to EPSA. We describe major steps in implementing EPSA for large-scale linear programming. Our implementation was carried out under the MATLAB environment. This algorithm seems to be more efficient than the classical pr...