New perturbation theorems for bases of singular subspaces are proved. These theorems complement the known sinΘ theorems for singular subspace perturbations, taking into account a kind of sensitivity of singular vectors discarded by previous theorems. Furthermore these results guarantee that high relative accuracy algorithms for the SVD are able to compute reliably simultaneous bases of left and...

Perturbation bounds for the relative error in the eigenvalues of diagonalizable and singular matrices are derived by using perturbation theory for simple invariant subspaces of a matrix and the group inverse of a matrix. These upper bounds are supplements to the related perturbation bounds for the eigenvalues of diagonalizable and nonsingular matrices. © 2006 Elsevier Inc. All rights reserved. ...

A new concept of “an imperfect singular solution” is defined as an approximate solution which becomes a singular solution by adding a suitable small perturbation to the original equations. A numerical method is presented for proving the existence of imperfect singular solutions of nonlinear equations with guaranteed accuracy. A few numerical examples are also presented for illustration. key wor...

In this paper, a steganography technique for JPEG2000 compressed images using singular value decomposition in wavelet transform domain is proposed. In this technique, DWT is applied on the cover image to get wavelet coefficients and SVD is applied on these wavelet coefficients to get the singular values. Then secret data is embedded into these singular values using scaling factor. Different com...

We expand a partial difference equation (P∆E) on multiple lattices and obtain the P∆E which governs its far field behaviour. The perturbative–reductive approach is here performed on well known nonlinear P∆Es, both integrable and non integrable. We study the cases of the lattice modified Korteweg–de Vries (mKdV) equation, the Hietarinta equation, the lattice Volterra–Kac–Van Moerbeke (VKVM) equa...