Let S be a semigroup. In certain cases we give some characterizations of extreme amenability of S and we show that in these cases extreme left amenability and extreme right amenability of S are equivalent. Also when S is a compact topological semigroup, we characterize extremely left amenable subalgebras of C(S), where C(S) is the space of all continuous bounded real valued functions on S

The duality between “regular” and “topological” as convergence space properties extends in a natural way to the more general properties “p-regular” and “p-topological.” Since earlier papers have investigated regular,p-regular, and topological Cauchy completions, we hereby initiate a study of p-topological Cauchy completions. A p-topological Cauchy space has a p-topological completion if and onl...

We describe a new multi-level algorithm to draw graphs based on the topological features they contain. Topological features are recursively detected and their subgraphs are collapsed into single nodes, forming a graph hierarchy. Once the hierarchy is computed, we draw the subgraphs of the hierarchy, using an appropriate algorithm for each topological feature. Our layout algorithms are areaaware...

Introduction. In an earlier article [9] the author developed at some length the theory of certain mathematical objects which he called linear systems. It is the purpose of the present paper to apply this theory to the study of convex topological linear spaces. This application is based on the many-to-one correspondence between convex topological linear spaces and linear systems which may be set...

Recently there has been an extensive study on Relative Semi-Dynamical Systems (RSD-Systems). In this paper, we explore some topological properties of RSD-systems. Here, in particular, minimal RSD-systems are characterized and transitive homeomorphisms are investigated. Moreover, α-level relative topological entropy is extended to RSD-systems. Finally, as a computational example, we develop an R...

This article describes a navigation system for a mobile robot which must execute motions in a building; the robot is equipped with a belt of ultrasonic sensors and with a camera. The environment is represented by a topological model based on a Generalized Voronoi Graph (GVG) and by a set of visual landmarks. Typically, the topological graph describes the free space in which the robot must navig...

We study the topologically twisted string theory on the general back-ground AdS3× N which is compatible with the world-sheet N = 2 superconformal symmetry and is extensively discussed in the recent works [20]. After summarizing the algebraic structure of the world-sheet topological theory, we show that the space-time (boundary) conformal theory should be also topological. We directly construct ...

By using the representational power of Chu spaces we define the notion of a generalized topological space (or GTS, for short), i.e., a mathematical structure that generalizes the notion of a topological space. We demonstrate that these topological spaces have as special cases known topological spaces. Furthermore, we develop the various topological notions and concepts for GTS. Moreover, since ...

In this paper we deal with a concrete example of a generalized topological space and we shall examine some topological properties such as, the usual continuity, the net-continuity and the net-closure property for it. We will show that a generalized topological space has net-continuous property or net-closure property if and only if it is a topological space. Finally we give examples of continuo...