204 research outputs found
Classical and Quantum Nonultralocal Systems on the Lattice
We classify nonultralocal Poisson brackets for 1-dimensional lattice systems
and describe the corresponding regularizations of the Poisson bracket relations
for the monodromy matrix . A nonultralocal quantum algebras on the lattices for
these systems are constructed.For some class of such algebras an
ultralocalization procedure is proposed.The technique of the modified
Bethe-Anzatz for these algebras is developed.This technique is applied to the
nonlinear sigma model problem.Comment: 33 pp. Latex. The file is resubmitted since it was spoiled during
transmissio
Drinfeld-Sokolov reduction for difference operators and deformations of W-algebras. II. General Semisimple Case
The paper is the sequel to q-alg/9704011. We extend the Drinfeld-Sokolov
reduction procedure to q-difference operators associated with arbitrary
semisimple Lie algebras. This leads to a new elliptic deformation of the Lie
bialgebra structure on the associated loop algebra. The related classical
r-matrix is explicitly described in terms of the Coxeter transformation. We
also present a cross-section theorem for q-gauge transformations which
generalizes a theorem due to R.Steinberg.Comment: 19 pp., AMS-LaTeX. The paper replaces a temporarily withdrawn text;
the first part (written by E. Frenkel, N. Reshetikhin, and M. A.
Semenov-Tian-Shansky) is available as q-alg/970401
Higgsless Electroweak Theory following from the Spherical Geometry
A new formulation of the Electroweak Model with 3-dimensional spherical
geometry in the target space is suggested. The free Lagrangian in the spherical
field space along with the standard gauge field Lagrangian form the full
Higgsless Lagrangian of the model, whose second order terms reproduce the same
fields with the same masses as the Standard Electroweak Model. The vector
bosons and electron masses are generated automatically, so there is no need in
special mechanism.Comment: 6 page
Multiplicative slices, relativistic Toda and shifted quantum affine algebras
We introduce the shifted quantum affine algebras. They map homomorphically
into the quantized -theoretic Coulomb branches of SUSY
quiver gauge theories. In type , they are endowed with a coproduct, and they
act on the equivariant -theory of parabolic Laumon spaces. In type ,
they are closely related to the open relativistic quantum Toda lattice of type
.Comment: 125 pages. v2: references updated; in section 11 the third local Lax
matrix is introduced. v3: references updated. v4=v5: 131 pages, minor
corrections, table of contents added, Conjecture 10.25 is now replaced by
Theorem 10.25 (whose proof is based on the shuffle approach and is presented
in a new Appendix). v6: Final version as published, references updated,
footnote 4 adde
Processing of basalt fiber production waste
The production of mineral rock wool forms a large proportion of off-test waste products. In addition to the cost of their production, there are costs for processing and utilization, such as transportation, disposal and preservation. Besides, wastes have harmful effect on the environment. This necessitates research aimed to study the stress-related characteristics of materials, their recyclability and use in the production of heat-saving product
Schwinger particle production: rapid switch off of the external field versus dynamical assistance
We consider the process of electron-positron pair production in the presence
of strong electric backgrounds being rapidly switched on and off and examine
the total particle yield. For sufficiently sharp field profiles, the particle
number can be substantially enhanced. It is demonstrated that this enhancement
is quite similar to the phenomenon of dynamical assistance by a weak
high-frequency field superimposed on a strong background. Both these mechanisms
are analyzed by means of exact numerical computations and the locally-constant
field approximation. We identify the time scale of the switching profile
leading to the pair-production enhancement and argue that the particle yield is
highly unlikely to be increased by shaping the switch off of realistic laser
pulses. On the other hand, we confirm that it is feasible to observe the
dynamically assisted Schwinger effect by adding a rapidly oscillating field to
a strong electric background.Comment: 9 pages, 5 figures, 1 tabl
Kinetic description of vacuum production in strong electric fields of arbitrary polarization
We present a detailed analysis of the self-consistent system of kinetic
equations (KEs) describing electron-positron pair production from vacuum under
the action of a spatially homogeneous time-dependent electric field of
arbitrary polarization. The physical significance of all the basic functions of
the kinetic theory is ascertained. It is demonstrated that the total system of
the KEs consists of two coupled quasiparticle and spin subsystems with their
integrals of motion. A projection method is proposed in order to obtain the KE
system in two particular cases: linearly polarized external electric field and
(2+1)-dimensional description of quasiparticles in graphene. We also address
the energy conservation law taking into account the internal plasma field and
describe an alternative rigorous derivation of the KE system.Comment: 15 page
Process organisation modelling for maintaining rail track geometry
Introduction. The increase in freight traffic density and axial loads on the Eastern polygon is affecting the condition of the railway and reducing the time available for maintenance. The increased workload caused by track deformation in difficult operating conditions makes the planning and organisation of railway maintenance work much more difficult. One of the main factors affecting the safety and smooth running of trains is the geometry of the rail track, which is kept in a normal condition by track maintenance. The study examines the problem of increasing the efficiency of maintaining rail track geometry.Materials and methods. Mathematical modelling and statistical methods were used to solve the problem. A process organisation model was created based on formalising the process of incoming and outgoing work. The estimated workload required to rectify the identified deviations was determined on the basis of the results of the track condition assessment using track measuring devices, taking into account the regulatory time standards for their rectification.Results. The mathematical model for the process organisation of rail track geometry maintenance is presented, which allows to determine the necessary level of daily workload on a linear section to perform the full scope of works within the regulated terms, which would reduce the desicion time during the planning of works.Discussion and conclusion. The use of this model makes it possible to simplify the planning and organisation of work on a section of track, which is particularly important at a high level of urgent and high-priority work on particularly heavy-traffic sections. Further research would focus on the development of a mathematical model, the development of a software product and its implementation into a unified enterprise automated infrastructure management system
Constructive and Technological Features of Units for Milling Polymer Material
Constructive and Technological Features of Units for Milling Polymer Material / V. S.Sevostyanov [et al.] // IOP Conf. Series: Journal of Physics. - 2018. - Vol.1066. - 012006.This article presents specific physical and mechanical properties of techno genic poly-mer materials. The features of their processing are revealed. The ways of constructive and techno-logical perfection of grinders are proposed, namely, the creation of units based on needle-milling working parts that ensure selective complex influence on the processed materials with the cantile-vered ends of their rod elements and the creation of energy-efficient mechanisms of destruction
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