Subspaces of $L\sb {p,q}$

Comment on frame's of subspaces

Covering of subspaces by subspaces

Lower and upper bounds on the size of a covering of subspaces in the Grassmann graph Gq(n, r) by subspaces from the Grassmann graph Gq(n, k), k ≥ r , are discussed. The problem is of interest from four points of view: coding theory, combinatorial designs, q-analogs, and projective geometry. In particular we examine coverings based on lifted maximum rank distance codes, combined with spreads and...

Frameness bound for frame of subspaces

In this paper, we show that in each nite dimensional Hilbert space, a frame of subspaces is an ultra Bessel sequence of subspaces. We also show that every frame of subspaces in a nite dimensional Hilbert space has frameness bound.

Factoring N = pq

We discuss the problem of factoring N = pq and survey some approaches. We then present a specialized factoring algorithm that runs in time Õ(q0.31), which is comparable to the runtime Õ(p) of the factoring algorithm for integers of the form N = pq presented in [1]. We then survey the factoring algorithm of [1] and discuss the number of advice bits needed for it to run in polynomial time. Furthe...

Eigenvalues-based LSB steganalysis

So far, various components of image characteristics have been used for steganalysis, including the histogram characteristic function, adjacent colors distribution, and sample pair analysis. However, some certain steganography methods have been proposed that can thwart some analysis approaches through managing the embedding patterns. In this regard, the present paper is intended to introduce a n...