We present the results of an empirical study of the performance of the QR algorithm (with and without shifts) and the Toda algorithm on random symmetric matrices. The random matrices are chosen from six ensembles, four of which lie in the Wigner class. For all three algorithms, we observe a form of universality for the deflation time statistics for random matrices within the Wigner class. For t...

The locally optimal block preconditioned 4-d conjugate gradient method (LOBP4dCG) for the linear response eigenvalue problem was proposed in [SIAM J. Matrix Anal. Appl., 34(2):392–416, 2013] and later was extended to the generalized linear response eigenvalue problem in [BIT Numer. Math., 54(1):31–54, 2014]. In this paper, we put forward two improvements to the method: a shifting deflation tech...

For quite some times, deflation preconditioner has been proposed and used to accelerate the convergence of Krylov subspace methods. For symmetric positive definite linear systems, convergence of CG combined with deflation has been analyzed and compared with other preconditioners, e.g. with the abstract balancing preconditioner [Nabben and Vuik, SIAM J. Sci. Comput., 27 (2006), pp. 1742–1759]. I...

Countries around the world have fallen into one of the deepest recessions since the Great Depression—a recession exacerbated by a severe financial crisis. Among the challenges that face monetary policymakers in such uncertain times is the danger economies worldwide, including the United States, Japan, and the euro area, may enter a period of deflation, in which the prices of goods and services ...

[1] The Bodélé Depression, Chad is the planet’s largest single source of dust. Deflation from the Bodélé could be seen as a simple coincidence of two key prerequisites: strong surface winds and a large source of suitable sediment. But here we hypothesise that long term links between topography, winds, deflation and dust ensure the maintenance of the dust source such that these two apparently co...

STUDY OBJECTIVE The influence of occlusion of the thoracic aorta by an intraluminal balloon on plasma atrial natriuretic peptide (ANP) levels was evaluated in humans. METHODS The changes in plasma ANP and plasma norepinephrine levels, and hemodynamic parameters were measured in 10 patients under general anesthesia undergoing regional chemotherapy treatment involving the 15-min inflation and s...

We tackle two questions in this paper: In the sovereign debt crisis, what moves the euro area inflation outlook and has the firm anchoring of medium to long-term inflation expectations been touched? Deriving densities from a new data set on options on the euro area harmonized index of consumer prices provides us with the full distribution of inflation expectations. The daily data set allows us ...

BACKGROUND In this prospective study we aimed at examining the effects of pneumatic tourniquet on intraocular pressure during elective knee surgery. METHOD Twenty patients undergoing elective knee surgery under general anesthesia with tracheal intubation were inluded the study. Anesthesia was induced with pentothal, rocuronium and fentanyl, then maintained with sevoflurane and nitrous oxide i...

Locking is a popular deflation technique followed by many eigensolvers, where a converged eigenvector is frozen and removed from the iteration search space. Other deflation techniques that do not modify the matrix have less favorable numerical properties, so the alternative to locking is not to perform deflation at all. Without deflation, which we refer to as non-locking, converged eigenvectors...

Radiographic imaging of magma dynamics in a volcanic conduit provides detailed information about ascent and descent of magma, the magma flow rate, the conduit diameter and inflation and deflation of magma due to volatile expansion and release. Here we report the first radiographic observation of the ascent and descent of magma along a conduit utilizing atmospheric (cosmic ray) muons (muography)...