Existence of fixed point in orthogonal metric spaces has been initiated recently by Eshaghi and et al. [On orthogonal sets and Banach fixed Point theorem, Fixed Point Theory, in press]. In this paper, we introduce the notion of the strongly orthogonal sets and prove a genuine generalization of Banach' fixed point theorem and Walter's theorem. Also, we give an example showing that our main theor...

a compact formulation of the set of tours neither in a graph nor its complement is presented and illustrates a general methodology proposed for constructing polyhedral models of decision problems based upon permutations, projection and lifting techniques. directed hamilton tours on n vertex graphs are interpreted as (n-1)- permutations. sets of extrema of birkhoff polyhedra are mapped to tours ...

In this paper we study the set of tensors that admit a special type decomposition called an orthogonal tensor train decomposition. Finding equations defining varieties low-rank is generally hard problem, however, orthogonally decomposable defined by appealing quadratic equations. The consider are extension tensors. We show they similar equations, as well interesting higher-degree additional equ...