The topography of the field and flux inside and above the surfaces of ferromagnetic plates during their contact and contactless magnetization

Modeling and experimental studies of the spatial distributions of the field and flux inside and above the surface of ferromagnetic plates of different dimension types, which were locally magnetized by U-shaped electromagnets, were performed. It was established that the location of a magnetic inhomogeneity in the interpole zone of an electromagnet substantially affects the results of a local measurement of the coercive force using a demagnetization current. It is shown that the presence of a gap in the magnetic circuit impairs the magnetization of the interpole zone of an object to a higher degree than the magnetization of the near-pole zone. Recommendations on the concentration of the magnetic flux in the interpole zone via a decrease in the interpole distance of the electromagnet are given. Possible locations of internal-field probes that provide local measurements of the magnetic properties of a substance are determined. © 2013 Pleiades Publishing, Ltd

Magnetic and acoustic characteristics of steel 30CrMnSiA after rolling and pressing

A group of magnetic and acoustic parameters of the cold-deformed 30CrMnSiA steel is determined. It has been revealed that the coercive force of this steel starts to decrease steadily at degrees of plastic deformation higher than 6%. A hypothesis is put forward on the relaxation of stresses of the first kind as a result of flat pressing after rolling of steel plates. To test the possibility of determining the degree of deformation of the 30CrMnSiA steel by ultrasound measurements, the propagation velocities of longitudinal, transverse, and Rayleigh waves are determined. The change in the velocity of longitudinal ultrasonic waves is 0.8% at deformation degrees ranging from 10 to 20%. The velocity of transverse and Rayleigh ultrasonic waves increases monotonically over the entire range of deformations, with a change in their velocity of 2.5% and 2.2% respectively. Thus, the most suitable parameter for determining the degree of deformation is the propagation velocity of transversal ultrasonic waves. © 2018 Author(s)

Synchronization transitions and sensitivity to asymmetry in the bimodal Kuramoto systems with Cauchy noise

We analyze the synchronization dynamics of the thermodynamically large systems of globally coupled phase oscillators under Cauchy noise forcings with bimodal distribution of frequencies and asymmetry between two distribution components. The systems with the Cauchy noise admit the application of the Ott-Antonsen ansatz, which has allowed us to study analytically synchronization transitions both in the symmetric and asymmetric cases. The dynamics and the transitions between various synchronous and asynchronous regimes are shown to be very sensitive to the asymmetry degree whereas the scenario of the symmetry breaking is universal and does not depend on the particular way to introduce asymmetry, be it the unequal populations of modes in bimodal distribution, the phase delay of the Kuramoto-Sakaguchi model, the different values of the coupling constants, or the unequal noise levels in two modes. In particular, we found that even small asymmetry may stabilize the stationary partially synchronized state, and this may happen even for arbitrarily large frequency difference between two distribution modes (oscillator subgroups). This effect also results in the new type of bistability between two stationary partially synchronized states: one with large level of global synchronization and synchronization parity between two subgroups and another with lower synchronization where the one subgroup is dominant, having higher internal (subgroup) synchronization level and enforcing its oscillation frequency on the second subgroup. For the four asymmetry types, the critical values of asymmetry parameters were found analytically above which the bistability between incoherent and partially synchronized states is no longer possible

Methods for estimating the optical constants of atmospheric hazes based on complex optical measurements

The methods of multifrequency laser sounding (MLS) are the most effective remote methods for investigating the atmospheric aerosols, since it is possible to obtain complete information on aerosol microstructure and the effective methods for estimating the aerosol optical constants can be developed. The MLS data interpretation consists in the solution of the set of equations containing those of laser sounding and equations for polydispersed optical characteristics. As a rule, the laser sounding equation is written in the approximation of single scattering and the equations for optical characteristics are written assuming that the atmospheric aerosol is formed by spherical and homogeneous particles. To remove the indeterminacy of equations, the method of optical sounding of atmospheric aerosol, consisting in a joint use of a mutifrequency lidar and a spectral photometer in common geometrical scheme of the optical experiment was suggested. The method is used for investigating aerosols in the cases when absorption by particles is small and indicates the minimum necessary for interpretation of a series of measurements

MODERN CONDITION AND PROSPECTS OF THE DEVELOPMENT OF ROUTE TRANSPORT OF PASSENGERS

The article analyzes the condition and prospects for the development of passenger route transport in the Russian Federation, provides the rationale for the need to improve the efficiency of public transport, which will contribute to the economic and social development of the city, region and the country as a whole. The existing problems were identified and a set of measures aimed at improving the efficiency of urban passenger transport was defined