Time dynamics of spins-fermional models in Cu2O

2021 ◽  
pp. 110-113
Author(s):  
V.S. Kirchanov ◽  
Keyword(s):  
System Of Equations ◽  
Spin Polaron ◽  
Harmonic Oscillations ◽  
Fermion Model ◽  
Time Dynamics ◽  
Coupling Operator ◽  
Frequency Harmonic

The solution of the system of equations for the basic operators of the spin-fermion model is obtained in the form of harmonic oscillations of Fermi operators at two frequencies, and three-frequency harmonic oscillations of the spin-fermion coupling operator (spin-polaron).

scholarly journals The Kinematic Analysis of the Screw Conveyor Vibration Exciter

2019 ◽  
Vol 297 ◽  
pp. 03004
Author(s):  
Dmitriy Kobylyansky ◽  
Viacheslav Gogolin
Keyword(s):  
The Body ◽  
Calculation Scheme ◽  
Polar Coordinates ◽  
Screw Conveyor ◽  
Vibration Exciter ◽  
System Of Equations ◽  
Harmonic Oscillations ◽  
Triangle Center ◽  
The Given ◽  
Rotating Bodies

The article presents a method of calculating the parameters of the screw conveyor vibration exciter. The calculation scheme of the new design of the vibration exciter, which allows to determine the parameters of the vibrations excited by this device taking into account the structural novelty and the specifics of the vibration exciter, in particular, in the screw reloader is also given. A system of equations describing the harmonic oscillations of the auger shaft axis, including the amplitudes of horizontal and vertical oscillations, is presented. As a result, a system of parametric equations describing the external and internal envelope line is obtained. When solving the system of equations, the equations of the boundary curves of internal and external rotating bodies are derived. The equations allow to calculate the trajectory of any point by its given polar coordinates. Examples of rotating bodies for different types of displacements of the triangle center in the calculation scheme, which are described by harmonic oscillations, are shown. The dependences of the body shape on the direction of oscillations along the coordinate axes are illustrated. It is shown that the transition from horizontal to vertical oscillations leads to a loss of symmetry of the body. The amplitude and frequency of oscillations also have a significant impact on the shape of the body. The forms of the rotating bodies, giving the possibility of combining the rotation and oscillation when driving on rollers are determined. The problem is generalized to an arbitrary number of regularly arranged rollers. The given technique gives the principal opportunity to create designs of vibrators that combine vibrations with rotation on rollers.

scholarly journals Spin-polaron damping in the spin-fermion model for cuprate superconductors

1998 ◽  
Vol 58 (10) ◽  
pp. 6194-6207 ◽  
Author(s):  
R. O. Kuzian ◽  
R. Hayn ◽  
A. F. Barabanov ◽  
L. A. Maksimov
Keyword(s):  
Cuprate Superconductors ◽  
Spin Polaron ◽  
Fermion Model

Canonical Submersion and Lie Homomorphisms Normal Subgroup

2020 ◽  
Vol 23 (1) ◽  
pp. 97-101
Author(s):  
Mikhail Petrichenko ◽  
Dmitry W. Serow
Keyword(s):  
Normal Subgroup ◽  
Canonical System ◽  
System Of Equations ◽  
Core Group ◽  
The Core ◽  
Switch Group

Normal subgroup module f (module over the ring F = [ f ] 1; 2-diffeomorphisms) coincides with the kernel Ker Lf derivations along the field. The core consists of the trivial homomorphism (integrals of the system v = x = f (t; x )) and bundles with zero switch group Lf , obtained from the condition ᐁ( ω × f ) = 0. There is the analog of the Liouville for trivial immersion. In this case, the core group Lf derivations along the field replenished elements V ( z ), such that ᐁz = ω × f. Hence, the core group Lf updated elements helicoid (spiral) bundles, in particular, such that f = ᐁU. System as an example Crocco shown that the canonical system does not permit the trivial embedding: the canonical system of equations are the closure of the class of systems that permit a submersion.

LIQUIDUS THERMO-BAROMETER FOR THE MODELING OF MAGNETITE — MELT EQUILIBRIUM

2018 ◽  
pp. 71-80
Author(s):  
N. S. Aryaeva ◽  
E. V. Koptev-Dvornikov ◽  
D. A. Bychkov
Keyword(s):  
Experimental Data ◽  
Liquidus Temperature ◽  
Vertical Structure ◽  
Maximum Error ◽  
Silicate Melt ◽  
System Of Equations ◽  
Wide Range ◽  
Basaltic Melts ◽  
Multidimensional Statistics

A system of equations of thermobarometer for magnetite-silicate melt equilibrium was obtained by method of multidimensional statistics of 93 experimental data of a magnetite solubility in basaltic melts. Equations reproduce experimental data in a wide range of basalt compositions, temperatures and pressures with small errors. Verification of thermobarometers showed the maximum error in liquidus temperature reproducing does not exceed ±7 °C. The level of cumulative magnetite appearance in the vertical structure of Tsypringa, Kivakka, Burakovsky intrusions predicted with errors from ±10 to ±50 m.

The spin-polaron concept in the theory of normal and superconducting states of cuprate

2020 ◽  
Author(s):  
Valerii V. Val'kov ◽  
Dmitrii M. Dzebisashvili ◽  
Maksim M. Korovushkin ◽  
Aleksandr F. Barabanov
Keyword(s):  
Spin Polaron

Study on the Modes of Operation of a Multi-Machine Installations with Mechanical Reduction

2019 ◽  
pp. 12-22
Author(s):  
A. M. Oleynikov ◽  
L. N. Kanov
Keyword(s):  
Mathematical Description ◽  
Reactive Power ◽  
Maximum Efficiency ◽  
Wind Flow ◽  
System Of Equations ◽  
Mechanical Equilibrium ◽  
Synchronous Generators ◽  
Electromagnetic Excitation ◽  
Number Of Generators ◽  
Wide Range

The paper gives the description of the original wind electrical installation with mechanical reduction in which the output of vertical axis wind turbine with rather low rotation speed over multiplicator is distributed to a certain number of generators. The number of acting generators is determined by the output of actual operating wind stream at each moment. According to this constructive scheme, it is possible to provide effective and with maximum efficiency installation work in a wide range of wind speeds and under any schedule issued to the consumer of electricity. As there are no any experience in using such complexes, mathematical description of its main elements is given, namely windwheels, generators with electromagnetic excitation of magnetic electrical type, then their interaction with windwheel, and also the results of mathematical modeling of work system regimes under using the offered system of equations. The basis for the mathematical description of the main elements of the installation – synchronous generators – are the system of equations of electrical and mechanical equilibrium in relative units in rotating coordinates without considering saturation of the magnetic circuit. The equation of mechanical equilibrium systems includes torque and brake windwheel electromagnetic moments of generators with taking into account the reduction coefficients and friction. In addition, we specify the alternator rotor dynamics resulting from continuous torque of windwheel fluctuations under the influence of unsteady wind flow and wind speed serving as the original variable is modeled by a set of sinusoids. Model simplification is achieved by equivalization of similar generators and by disregarding these transitions with a small time constant. Calculation the installation with synchronous generators of two types of small and medium capacity taking into account the operational factors allowed us to demonstrate the logic of interactions in the main elements of the reported complex in the process of converting wind flow into the generated active and reactive power. We have shown the possibility of stable system work under changeable wind stream condition by regulating of the plant blade angle and with simultaneous varying of generator number of different types. All these are in great interest for project organizations and power producers.

Sign in / Sign up

Export Citation Format

Share Document