The concept of strong almost convergence was introduced by Maddox in 1978 [Math. Proc. Camb. Philos. Soc., 83 (1978), 61-64] which has various applications. In this paper we introduce some new sequence spaces which arise from the notions of strong almost convergence and an Orlicz function in a seminormed space. A new concept of uniform statistical convergence in a seminormed space has also been...

A generalization of the cosine of the Friedrichs angle between two subspaces to several closed subspaces in a Hilbert space is given. This is used to analyze the rate of convergence in the von Neumann-Halperin method of cyclic alternating projections. General dichotomy theorems are proved, in the Hilbert or Banach space situation, providing conditions under which the alternative QUC/ASC (quick ...

In this paper we study the approximation by rectangular partial sums of a double Fourier series with respect to the Walsh–Kaczmarz system in the spaces C and L. From our results we obtain different criteria of the uniform convergence and L-convergence of a double Fourier–Kaczmarz series. 2000 Mathematics Subject Classification: Primary 41A50; Secondary 42C10.