Aggressive early deflation has proven to significantly enhance the convergence of the QR algorithm for computing the eigenvalues of a nonsymmetric matrix. One purpose of this paper is to point out that this deflation strategy is equivalent to extracting converged Ritz vectors from certain Krylov subspaces. As a special case, the single-shift QR algorithm enhanced with aggressive early deflation...

This article proposes an anti-fake QR codes watermarking algorithm based on the DWT and SVD, aiming at the security problem of QR code in the actual application. Firstly, this paper analyses the advantage of QR code as well as its problems. Secondly, the principle of the chaos encryption and discrete wavelet transform are introduced in detail. Then, we design a new watermarking barcode by the c...

In this paper we discuss the deflation criterion used in the extended QR algorithm based on the chasing of rotations. We provide absolute and relative perturbation bounds for this deflation criterion. Further, we present a generalization of aggressive early deflation to the extended QR algorithms. Aggressive early deflation is the key technique for the identification and deflation of already co...

In this paper we propose an e-voting authentication scheme combined with QR-codes and visual cryptography. We focus on the usability, in order to supply voters with less technical experience with a usable scheme. The only requirement is that the user needs to handle a device containing a QR-code reader, most probably a smartphone. This approach is based on visual cryptography as the work horse:...

In this paper, we present a new QR based algorithm for IIR adaptive filtering. This algorithm achieves a reduction of complexity with regard to the IIR-QR algorithm by using a block reduction transformation. Moreover, this new approach make it possible to directly transform fast FIR algorithm into fast O (N) versions of the IIR algorithm. Therefore, we derive a fast version of the algorithm fro...

The implementation on vector computers of the QR algorithm and of iterative schemes based on obtaining the determinant and its derivatives by Hyman's method are presented. It is shown that iterative schemes based on Hyman's method will probably be more efficient than the QR algorithm on vector computers for large matrices. A theoretical comparison of the Laguerre iterative scheme with the QR al...

Though the rapid development and spread of Information and Communication Technology (ICT) making people's life much more easier, on the other hand it causing some serious threats to the society. Phishing is one of the most common cyber threat, that most users falls in. This research investigate on QR code based phishing attacks which is a newly adopted intrusive method and how to enhance the aw...

Recently, quantile regression (QR) models are often applied for longitudinal data analysis. When the distribution of responses seems to be skew and asymmetric due to outliers and heavy-tails, QR models may work suitably. In this paper, a semi-parametric quantile regression model is developed for analysing continuous longitudinal responses. The error term's distribution is assumed to be Asymmetr...