Iranian Journal of Mathematical Sciences and Informatics
Volume:1 Issue: 2, Nov 2006

For a unital foundation topological -semigroup S whose representationsseparate points of S, we show that the spectrum of theFourier-Stieltjes algebra B(S) is a compact semitopological semigroup.We also calculate B(S) for several examples of S.Keywords: Fourier algebra, Fourier-Stieltjes algebra, amenability, weaklyand strongly almost periodic functions, spectrum, foundation topologicalsemigroups

ABSTRACT. In this paper we consider a kind of higher-order evolution equation asku ¶tk + ¶k−1u ¶tk−1 +···+ut −4u= f (u,5u,x). For this equation, we investigate nonglobal solution, blow-up in finite time and instantaneous blow-up under some assumption on k, f and initial data. In this paper we employ the Test function method, the Generalized convexity method and Galerkin’s method for some of our proofs. Moreover, occasionally by changing P.D.E problems to some ordinary differential inequalities, we investigate this kind of higher-order evolution equations.

Involving the Ricci curvature and the squared mean curvature, we obtain basic inequalities for different kind of submaniforlds of a Sasakian space form tangent to the structure vector field of the ambient manifold. Contrary to already known results, we find a different necessary and sufficient condition for the equality for Ricci curvature of C-totally real submanifolds of a Sasakian space form, and (2) of the fact that if a C-totally real submanifold of maximum dimension satisfies the equality case, then it must be must be minimal. Two basic inequalities for submanifolds of any Riemannian manofild, one involving scaler curvature and the squared mean curvature and the other involving the invariant and the squared mean curvature are also obtained. These results are applied to get corresponding results for submanifolds of Sasakian space forms.

A tree T of order n is called k-placement if there are k edge-disjoint copies of T into K_{n}. In this paper we prove some results about 4-placement of rooted trees.

In this paper, we consider characterizations based on the Bhattacharyya matrices. We characterize, under certain constraint, distributions such as normal, compound poisson and gamma via the diagonality of the 2 × 2 Bhattacharyya matrix.