On Optimization of Tax Functions

Mathematical Notes - We consider the problem of maximization of an integral functional on the space of increasing functions, which is motivated by economic concerns for tax mechanisms optimization....     

Investigations and Modeling of the Effect of Magnetic Nanoparticles on MR Image Contrast

The investigations of nuclear magnetic resonance (NMR) relaxation of protons in aqueous solution and 2% agar–agar gel in the presence of magnetic nanoparticles were performed. To identify the effect of magnetic nanoparticles on the contrast of magnetic resonance images, the dependences of the MR signal intensity on the parameters of the two pulse radio-frequency (RF) sequences (spin-echo, gradient-echo) most commonly used in MRI for different values of the magnetic nanoparticle (MNP) concentration were simulated and analyzed. Recommendations for choosing the optimal values of pulse RF sequence parameters for MR imaging (MRI) in the presence of MNPs are formulated. MRI studies of phantom samples with 2% agar–agar gel containing MNPs have been performed for choosing the fast pulse RF sequence which shows the greatest contrast effect on MR images. A program for modeling magnetic resonance tomograms and determination of optimal values of pulse RF sequence parameters to achieve the best contrast of magnetic resonance images is developed. This program allows to reduce the time of MRI studies, to assess the possibility of using MNPs for contrast of MR images and to simulate the MR image in the presence of magnetic nanoparticles at the planning stage of procedures in MR-guided theranostics.     

Nanostructure Evolution of Oxide Dispersion Strengthened Steels under Fe Ion Irradiation at 350°C

Physics of Atomic Nuclei - Improved mechanical properties of oxide dispersion strengthened (ODS) steels, the advanced materials for the reactor core, are due to the high density of uniformly...     

Strong solutions to stochastic equations with a Lévy noise and a non-constant diffusion coefficient

The goal of this study is to prove an existence and uniqueness theorem for the solution of a stochastic differential equation with Lévy noise in the case where the drift coefficient can be discontinuous. Additionally, the differentiability of the solution with respect to the initial condition is proved.     

Weighted Zolotarev metrics and the Kantorovich metric

In this paper we study properties of weighted Zolotarev metrics and compare them with the Kantorovich metric.     

Identifying the elastic properties of an inhomogeneously thick layer

We consider the problem of reconstructing inhomogeneously thick elasticity moduli of an isotropic layer in analyzing steady-state vibration. The problem reduces to a one-dimensional coefficient of an inverse problem whose solution is constructed with the use of iteration schemes for integral Fredholm equations of the first and second kind. We consider model examples of reconstructing the layer characteristics and discuss various aspects of numerical realization.     

A Solution-Solid Phase Equilibrium in Ternary Systems Containing d-Elements Salts and Mixed Oxygen-Donor Solvent

Russian Journal of General Chemistry - The results of the study of ternary systems containing copper, cobalt, nickel, and cadmium halides and sulfates in binary water-organic and mixed organic...