State of Chromium in Solid Solutions of Complex Bismuth Niobates Bi2BaCrxNb2-xO9(0.01 < x < 0.3)

Magnetic susceptibility and electric properties of complex bismuth niobates with the layered perovskite structure, containing chromium(III) atoms in niobium(V) sites, were studied. Clusters of chromium(III) atoms with a high antiferromagnetic exchange parameter (−45 cm⁻¹) were found, whose formation along the c axis of the structure is associated with the presence of vacancies in the oxygen sublattice.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 1, 2005, pp. 24–28.Original Russian Text Copyright © 2005 by Chezhina, Piir, Zhuk.     

Optimal algorithm of panoramic sewing of images in the presence of inaccuracies of mutual positioning

An optimal algorithm of panoramic sewing of images in the presence of alignment errors has been synthesized on the basis of the criterion of a posteriori probability maximum. It was shown that in case of stationary images and equal a priori probabilities of image shifts, the shift estimate is determined by a maximum of the cross-correlation function of a pair of overlapping images. The sewing algorithm proposed was illustrated by the sewing of real images.     

Reports read at the international conference on the theory of approximation of functions held at Kaluga,july 24–28, 1975

Mathematical Notes -     

Sharp Estimates for the Norms of Differences in Terms of the Norms of the Derivatives and the Best Majorants of Moduli of Continuity of Periodic Functions

Let C be the space of 2-periodic continuous functions with uniform norm, let _r(f,h) be a modulus of continuity of order r of a function f, and let

Axisymmetric Dynamic Problem of Coupled Thermoviscoplasticity

An axisymmetric dynamic thermoviscoelastic problem is formulated with allowance for the coupling of mechanical and thermal fields. The behavior of the material is described by the Bodner–Partom model. A technique for numerical solution of the problem is developed. The laws governing the stress–strain state and the temperature field of a circular disk under forced flexural vibrations are studied