The problem of steady, laminar and incompressible natural convection flow in an octagonalenclosure was studied. In this investigation, two horizontal walls were maintained at a constant hightemperature, two vertical walls were kept at a constant low temperature and all inclined walls wereconsidered adiabatic. The enclosure was assumed to be filled with a Bousinessq fluid. The studyincludes comp...

The octagonal mesh is a variation of the two-dimensional (2D) mesh topology in which each processing element is connected to its eight closest neighbors. This paper studies the octagonal mesh as a topology for a wormhole-routed multiprocessor. A unicast routing algorithm and two multicast routing algorithms are presented and shown to be deadlock-free. Simulation results are given that compare m...

In this study, an octagonal-based self-organizing network’s lattice structure is proposed to allow more exploration and exploitation in updating the weights for better mapping and classification performances. The neighborhood of the octagonal-based lattice structure provides more nodes for the weights updating than standard hexagonal-based lattice structure. Based on our experiment, the octagon...

we present a new renormalization-group calculation of the octagonal tiling excitation spectrum. Two new self-;imilar octagonal tilings are introduced, a triangle-Lite and a triangle-dan tiling, which are entangled with the standard rhombus-~quare tiling. The decimation procedure involved in the renormalization group calculation transforms each tiling enta a different one and goe; back tu the (r...

In this paper a geometric approach is suggested to ®nd the closest approximation to Euclidean metric based on geometric measures of the digital circles in 2D and the digital spheres in 3D for the generalized octagonal distances. First we show that the vertices of the digital circles (spheres) for octagonal distances can be suitably approximated as a function of the number of neighborhood types ...

Symmetric spiral inductors are used for differential circuit applications for their robustness and superior noise rejection properties. In this work, characteristics of quality factor and inductance of symmetric inductors having octagonal structures, and the methods to improve performance have been suggested using the Agilent Momentum simulator [1]. From the results, we get differential quality...

In this paper we prove that the transitive closure of a nondeterministic octagonal relation using integer counters can be expressed in Presburger arithmetic. The direct consequence of this fact is that the reachability problem is decidable for flat counter automata with octagonal transition relations. This result improves the previous results of Comon and Jurski [7] and Bozga, Iosif and Lakhnec...

The theory of magnetic symmetry in quasicrystals, described in a companion paper [Acta Crystallographica AXX (2003) xxx-xxx], is used to enumerate all 3-dimensional octagonal spin point groups and spin space-group types, and calculate the resulting selection rules for neutron diffraction experiments. 1. Introduction We enumerate here all three-dimensional octagonal spin groups and calculate the...