Optimization of Methodological Support of the Tax Benefits Implementation in the Regions: the Practice of the Perm Territory

In the article, the problem of the methodological process support of regional tax benefits is reviewed. The method of tax benefits assessment, accepted in Perm Region, was chosen as an analysis object because the relatively long period of application of benefits has allowed to build enough statistics base. In the article, the reliability of budget, economic, investment, and social effectiveness assessments of application benefits, based on the Method, is investigated. The suggestions of its perfection are formulated

Flux domes in superconducting films without edges

Domelike magnetic-flux-density distributions previously have been observed experimentally and analyzed theoretically in superconducting films with edges, such as in strips and thin plates. Such flux domes have been explained as arising from a combination of strong geometric barriers and weak bulk pinning. In this paper we predict that, even in films with bulk pinning, flux domes also occur when vortices and antivortices are produced far from the film edges underneath current-carrying wires, coils, or permanent magnets placed above the film. Vortex-antivortex pairs penetrating through the film are generated when the magnetic field parallel to the surface exceeds H_{c1}+K_c, where H_{c1} is the lower critical field and K_c = j_c d is the critical sheet-current density (the product of the bulk critical current density j_c and the film thickness d). The vortices and antivortices move in opposite directions to locations where they join others to create separated vortex and antivortex flux domes. We consider a simple arrangement of a pair of current-carrying wires carrying current I_0 in opposite directions and calculate the magnetic-field and current-density distributions as a function of I_0 both in the bulk-pinning-free case (K_c = 0) and in the presence of bulk pinning, characterized by a field-independent critical sheet-current density (K_c > 0).Comment: 15 pages, 23 figure

Phonon assisted tunneling in Josephson junctions

The expression for additional subgap current in the presence of electron-phonon interaction is derived. We show that the phonon assisted tunneling leads to appearance of peaks on current-voltage characteristics at the Josephson frequencies corresponding to the Raman-active phonons. The relation of the obtained results to experimental observations are discussed.Comment: 8 pages, submitted to PR

On an algorithm for dynamic reconstruction of the input

We consider the problem of dynamic reconstruction of the input in a system described by a vector differential equation and nonlinear in the state variable. We indicate an algorithm that is stable under information noises and computational errors and is aimed at infinite system operation time. The algorithm is based on the dynamic regularization method. © 2013 Pleiades Publishing, Ltd

On a reconstruction algorithm for the trajectory and control in a delay system

We discuss a problem of the dynamic reconstruction of unmeasured coordinates of the phase vector and unknown controls in nonlinear vector equations with delay. A regularizing algorithm is proposed for the reconstruction of both controls and unmeasured coordinates simultaneously with the processes. The algorithm is stable with respect to information noises and computational errors. © 2013 Pleiades Publishing, Ltd

Critical temperature and giant isotope effect in presence of paramagnons

We reconsider the long-standing problem of the effect of spin fluctuations on the critical temperature and isotope effect in a phonon-mediated superconductor. Although the general physics of the interplay between phonons and paramagnons had been rather well understood, the existing approximate formulas fail to describe the correct behavior of $$ for general phonon and paramagnon spectra. Using a controllable approximation, we derive an analytical formula for $T_{c}$ which agrees well with exact numerical solutions of the Eliashberg equations for a broad range of parameters. Based on both numerical and analytical results, we predict a strong enhancement of the isotope effect when the frequencies of spin fluctuation and phonons are of the same order. This effect may have important consequences for near-magnetic superconductors such as MgCNi$_{3}$Comment: 5 pages, 2 figure

On an Algorithmfor the Reconstruction of a Perturbation in a Nonlinear System

A problem of reconstruction of an unknown perturbation in a system of nonlinear ordinary differential equations is considered. The methods of solution of such problems are well known. In this paper we study a problem with two peculiarities. First, it is assumed that the phase coordinates of the dynamical system are measured (with error) at discrete sufficiently frequent times. Second, the only information known about the perturbation acting on the system is that its Euclidean norm is square integrable; i.e., the perturbation can be unbounded. Since the exact reconstruction is impossible under these assumptions, we design a solution algorithm that is stable under information noise and computation errors. The algorithm is based on the combination of elements of the theory of ill-posed problems with the extremal shift method known in the theory of positional differential games. © 2020 Krasovskii Institute of Mathematics and Mechanics. All rights reserved