Equivariant version of uniform flow is introduced in order to study the notions of the complete invariance property, and also that of the complete invariance property with respect to a homeomorphism, in the category of topological transformation groups.

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In this paper, we propose an equivalent form of the restricted generalized absolute continuity, which characterizes the Denjoy integral of real valued functions.

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In this paper, we prove a fixed point theorem for widely more generalized hybrid non-self mappings in Hilbert spaces. Furthermore, we prove mean convergence theorems of Baillon’s type for widely more generalized hybrid non-self mappings in a Hilbert space.

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In this paper, by considering the notions of left-right and right-left derivations of BCI-algebras, we generalize some results on regular derivations and classify this derivation in P-semisimple BCI-algebra and BCK-algebra. Then we make a congruence relation, for any derivation d of X and defined the concept of conjugate derivations. In the sequel, we show that the set of all equivalence classes of X with respect to this relation forms a BCI-algebra and we denote it by X/d. Finally, we get some interesting result about these quotient algebras.

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We investigate conditions under which a convex or co-convex set in a normed space is tightly bordered, in the sense that a point of the set that is bounded away from its boundary lies in the interior of the set. The investigation lies entirely within a constructive framework.

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We give a general and explicit formula for the moments of the limiting distribution of symmetric self-nomalized sum of i.i.d. random variables, which belong to the domain of attraction of a stable law. The result shows that the finite order moments for symmetric selfnormalized sums are always finite. As an application, tail index can be estimated through our result by using moment estimators.

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In the present paper we introduce some double sequence spaces defined by a sequence of Orlicz functionsM= (Mk,l) over n-normed spaces. We study some topological properties and prove some inclusion relations between these spaces.

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In this paper we introduce the notion of ˆω-closed sets in topological spaces and obtain some of the basic properties of this class of sets. Further more their relationships with other generalized closed sets are investigated. It turns out that this class lies between the class of a-closed sets and the class of gα-closed sets. And some ˆω-closure formulas in subspaces are investigated in the end of the present paper.

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A combinatorial optimization problem, namely k-Cardinality Tree Problem, is to find a subtree with exactly k edges in an undirected graph G, such that the sum of edges’ weights is minimal. Since this problem is NP-hard, though many heuristic and metaheuristic methods are widely adopted, the precision of these methods is not well enough. In this paper we shall give a Memetic Algorithm based on Tabu Search for solving this problem. The crossover in Memetic Algorithm acts as a powerful diversitification strategy, which enlarges search area effectively. The experimental results show that the proposed algorithm is superior to existing algorithms both in precision and computing time. We arrive at a conclusion that a well designed hybrid metaheuristic algorithm is efficient for solving the k-Cardinality Tree Problem.

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We revisit and study the Euler characteristic for C* -algebras and obtain the Euler-Poincar´e formula for C* -algebras, as a noncommutative version of the classical Euler-Poincar´e formula for spaces.

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Let A be a C*-algebra and let X be a Hilbert C*-module over A. Isidro[2] showed the theorem that X becomes a JB*-triple in a canonical way. We give a simple and alternative proof of Isidro’s theorem.

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