Iranian Journal of Mathematical Sciences and Informatics
Year:2012 | Volume:7 | Issue:1|Papers Count:8

In this paper, we study the class of C 3-like Finsler metrics which contains the class of semi-C-reducible Finsler metric. We find a condition on C 3-like metrics under which the notions of Landsberg curvature and mean Landsberg curvature are equivalent.

In this paper, by using the notion of fuzzy subsets, the concept of F-permutation is introduced. Then by applying this notion the concepts of presentation of an F-polygroup, graph of an F-permutation and F-permutation matrices are investigated.

Some common fixed point theorems for Cq -commuting generalized nonexpansive mappings have been proved in metric spaces. As applications, invariant approximation results are also obtained. The results proved in the paper extend and generalize several known results including those of M. Abbas and J.K. Kim [Bull. Korean Math. Soc.44 (2007) 537-545], I. Beg, N. Shahzad and M. Iqbal [Approx. Theory Appl.8 (1992) 97-105], W.G. Dotson [J. London Math. Soc.4 (1972) 408-410, Proc.Amer. Math. Soc.38 (1973) 155-156.], M. D. Guay, K. L. Singh and J.H. M. Whitfield [Proc. Conference on nonlinear analysis (Ed. S.P.Singh and J. H. Bury) Marcel Dekker 80 (1982) 179-189], L. Habiniak [J. Approx.Theory 56 (1989) 241-244], N. Hussain and B.E. Rhoades [Fixed Point Theory Appl. Vol.2006, Article ID 24543, 1-9], T.D. Narang and S. Chandok [Indian J. Math.51 (2009) 293-303, Ukrainian Math. J.62 (2010) 1367-1376], N. Shahzad [Fixed point Theory Appl.1 (2005) 79-86] and of Y. Song [Comm. Math. Anal.2 (2007) 17-26].

Finite tight frames have many applications and some interesting physical interpretations. One of the important subjects in this area is the ways for constructing such frames. In this article we give a concrete method for constructing finite normalized frames using Platonic solids.

In this paper, stability for uncertain time variant linear systems with time delay is studied. A new sufficient condition for delay-dependent systems is given in matrix inequality form which depends on the range of delay. Then, we introduce a new direct computational method to solve delay systems. This method consists of reducing the delay problem to a set of algebraic equations by first expanding the candidate function as hybrid functions with unknown coefficients. By using collocation method, the coefficients of the hybrid functions are obtained.Some numerical examples are given to illustrate and compare our results with other existing methods in the literature.

In this article, first we generalize the concept of complete parts in hyperrings by introducing the concept Â-parts in hyperrings and then we study Â-closures in hyperrings. Finally we characterize Â- closures in hyperfields.

Let G and H be graphs. The tensor product GÄH of G and H has vertex set V (G Ä H) = V (G) × V (H) and edge set E(G  Ä H) = {(a, b)(c, d)|ac ∈ E(G) and bd ∈ E(H)}. In this paper, some results on this product are obtained by which it is possible to compute the Wiener and Hyper Wiener indices of Kn Ä G.

We provide some new sharp embeddings for p-Carleson measures and some related measures in the unit disk of the complex plane.