285 research outputs found
Computer Simulation of a Plasma Vibrator Antenna
The use of new plasma technologies in antenna technology is widely discussed nowadays. The plasma antenna must receive and transmit signals in the frequency range of a transceiver. Many experiments have been carried out with plasma antennas to transmit and receive signals. Due to lack of experimental data and because experiments are difficult to carry out, there is a need for computer (numerical) modeling to calculate the parameters and characteristics of antennas, and to verify the parameters for future studies. Our study has modeled plasma vibrator (dipole) antennas (PDA) and metal vibrator (dipole) antennas (MDA), and has calculated the characteristics of PDAs and MDAs in the full KARAT electro-code. The correctness of the modeling has been tested by calculating a metal antenna using the MMANA program
PROBLEMS OF DIGITALIZATION OF THE RUSSIAN INDUSTRY
The article is devoted to the substantiation of the model of the formation of an industrial development ecosystem based on modern digital technologies in industry.The article deals with the problems of technological sovereignty of the Russian economy. It is shown that the solution of this problem is possible only on the basis of an industrial development ecosystem â a system of production chains of the most important types of industrial products, a technological development platform, interaction of subjects of industrial production with consumers of its products in the domestic and foreign markets. The necessity of concentration of industrial potential, resources of technological development, qualified personnel potential and direction to create conditions for providing the Russian economy with products corresponding to the world technological level is shown. The article analyzes the main existing and promising models of the functioning of an industrial enterprise. A detailed description of the barriers and difficulties on the way of digitalization of industrial enterprises in the Russian Federation is given.In order to form the ecosystem of industrial development of the Russian Federation, the directions of identifying and assessing the state of production and technological personnel potential, its compliance with the needs of the domestic market are formulated. Recommendations are given on the creation of an ecosystem structure, mechanisms for the interaction of its various elements, a management and coordination system based on digital technologies for creating a system of individual elements that form information and analytical centers in various functional areas of the ecosystem.A model of the ecosystem of industrial and technological development of the Russian economy based on digital technologies is proposed.A set of mechanisms that contribute to reducing the level of uncertainty is proposed, and a design method of interaction within the framework of the digital industrial enterprise technology platform model is described.The article formulates recommendations for the digitalization of an industrial enterprise in the new technological conditions of economic and social development, in the so-called new technological paradigm âIndustry 4.0â, the characteristic features of which are minimal use of manual and mechanized labor, as well as a low level of transaction costs.A new approach is proposed, on the basis of which industrial enterprises will interact on the basis of shared access to information and digital resources and the ability to combine the development of innovative projects and value chains necessary to create competitive products in order to increase the operational efficiency of enterprises
Uniform shrinking and expansion under isotropic Brownian flows
We study some finite time transport properties of isotropic Brownian flows.
Under a certain nondegeneracy condition on the potential spectral measure, we
prove that uniform shrinking or expansion of balls under the flow over some
bounded time interval can happen with positive probability. We also provide a
control theorem for isotropic Brownian flows with drift. Finally, we apply the
above results to show that under the nondegeneracy condition the length of a
rectifiable curve evolving in an isotropic Brownian flow with strictly negative
top Lyapunov exponent converges to zero as with positive
probability
Light Baryon Resonances: Restrictions and Perspectives
The problem of nucleon resonances N' with masses below the Delta is
considered. We derive bounds for the properties of such states. Some of these
are new, while others improve upon existing limits. We discuss the nature of N'
states, and their unitary partners, assuming their existence can be verified.Comment: 11 pages, 11 figur
Calculus and heat flow in metric measure spaces and applications to spaces with Ricci bounds from below
This paper is devoted to a deeper understanding of the heat flow and to the
refinement of calculus tools on metric measure spaces (X,d,m). Our main results
are:
- A general study of the relations between the Hopf-Lax semigroup and
Hamilton-Jacobi equation in metric spaces (X,d).
- The equivalence of the heat flow in L^2(X,m) generated by a suitable
Dirichlet energy and the Wasserstein gradient flow of the relative entropy
functional in the space of probability measures P(X).
- The proof of density in energy of Lipschitz functions in the Sobolev space
W^{1,2}(X,d,m).
- A fine and very general analysis of the differentiability properties of a
large class of Kantorovich potentials, in connection with the optimal transport
problem.
Our results apply in particular to spaces satisfying Ricci curvature bounds
in the sense of Lott & Villani [30] and Sturm [39,40], and require neither the
doubling property nor the validity of the local Poincar\'e inequality.Comment: Minor typos corrected and many small improvements added. Lemma 2.4,
Lemma 2.10, Prop. 5.7, Rem. 5.8, Thm. 6.3 added. Rem. 4.7, Prop. 4.8, Prop.
4.15 and Thm 4.16 augmented/reenforced. Proof of Thm. 4.16 and Lemma 9.6
simplified. Thm. 8.6 corrected. A simpler axiomatization of weak gradients,
still equivalent to all other ones, has been propose
Bosonization method for second super quantization
A bosonic-fermionic correspondence allows an analytic definition of
functional super derivative, in particular, and a bosonic functional calculus,
in general, on Bargmann- Gelfand triples for the second super quantization. A
Feynman integral for the super transformation matrix elements in terms of
bosonic anti-normal Berezin symbols is rigorously constructed.Comment: In memoriam of F. A. Berezin, accepted in Journal of Nonlinear
Mathematical Physics, 15 page
Evolution of microstructure in advanced ferritic-martensitic steels under irradiation : the origin of low temperature radiation embrittlement
Advanced reduced activation ferritic/martensitic steels and oxide dispersion-strengthened steels exhibit significant radiation embrittlement under low temperature neutron irradiation. In this study we focused on atom probe tomography (APT) of Eurofer97 and ODS Eurofer steels irradiated with neutrons and heavy ions at low temperatures. Previous TEM studies revealed dislocation loops in the neutron-irradiated f\m steels. At the same time, our APT showed early stages of solid solution decomposition. High density (10 m) of âŒ3â5 nm clusters enriched in chromium, manganese, and silicon atoms were found in Eurofer 97 irradiated in BOR-60 reactor to 32 dpa at 332°C. In this steel irradiated with Fe ions up to the dose of 24 dpa, pair correlation functions calculated using APT data showed the presence of Cr-enriched pre-phases.
APT study of ODS Eurofer found a significant change in the nanocluster composition after neutron irradiation to 32 dpa at 330 °C and an increase in cluster number density. APT of ODS steels irradiated with Fe ions at low temperatures revealed similar changes in nanoclusters.
These results suggest that irradiation-induced nucleation and evolution of very small precipitates may be the origin of low temperature radiation embrittlement of f\m steels
Supersymmetry and LHC
The motivation for introduction of supersymmetry in high energy physics as
well as a possibility for supersymmetry discovery at LHC (Large Hadronic
Collider) are discussed. The main notions of the Minimal Supersymmetric
Standard Model (MSSM) are introduced. Different regions of parameter space are
analyzed and their phenomenological properties are compared. Discovery
potential of LHC for the planned luminosity is shown for different channels.
The properties of SUSY Higgs bosons are studied and perspectives of their
observation at LHC are briefly outlined.Comment: Lectures given at the 9th Moscow International School of Physics
(XXXIV ITEP Winter School of Physics
Uniqueness for continuity equations in Hilbert spaces with weakly differentiable drift
Effect of heavy-ion irradiation on the nanoscale state of advanced reactor ferritic-martensitic steels
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