01.00.00 Physical-mathematical sciences
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SIMULATION OF TURBULENT FLOW IN A CAVITY ON THE NAVIER-STOKES EQUATIONS
01.00.00 Physical-mathematical sciences
DescriptionThe article deals with the numerical solution of the Navier-Stokes equations describing turbulent flow in a rectangle cavity or in a cuboid with one open face at high Reynolds numbers. It is known, that there is a mechanism of turbulent mixing in natural systems, leading to an increase in the viscosity of the continuous medium. In this regard, we suggest methods of regularization of the Navier-Stokes equations, similar to the natural mechanisms of mixing. We proposed the models based on the properties of the turbulent environment. For this we modified the continuity equation taking into account the pressure fluctuations. It is shown that the incompressibility condition is can be violated due to pressure fluctuation even for flows with low Mach numbers. Modification of continuity equation by the introduction of turbulent viscosity allows the regularization of the Navier-Stokes equations to solve the problems with rapidly changing dynamic parameters. It was shown that the modification of the continuity equation taking into account turbulent fluctuations leads to a system of nonlinear equations of parabolic type. A numerical model of turbulent flow in the cavity with the rapid change in the parameters of the main flow developed. Discovered type of instability of the turbulent flow associated with the rapid changes in the main flow velocity. In numerical simulations found that due to the acceleration of the main flow there is the unsteady vortex flow in the cavity, which is characterized by the integral of energy not vanishing with time, vibrations that have a certain period, depending on the turbulent viscosity
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SIMULATION OF BALL LIGHTNING IN CONDUCTING ENVIRONMENT
01.00.00 Physical-mathematical sciences
DescriptionIn this work, a model is developed to describe the formation of streamers, plasmoid, and ball lightning in a conducting medium. To describe the contribution of the conductivity currents, we modified the standard electrostatic equation taking into account the vortex component of the electric field. As a result of this generalization, a system of parabolic-type nonlinear equations is formulated that describes the formation of streamers, plasma long-lived formations and ball lightning. As is known, in laboratories it is possible to create a plasmoid with a lifetime of 300-500 ms and a diameter of 10-20 cm, which is interpreted as a ball lightning. With high-speed photography, a complex structure is detected, consisting of a plasmoid and surrounding streamers. Within the framework of the proposed model, problems are posed about the formation of a plasmoid and the propagation of streamers in an external electric field. In this model, the plasmoid is considered to be a long-lived streamer. The range of parameters in which a plasmoid of spherical shape is formed is indicated. It is established that there are three streamer branching mechanisms. The first mechanism is related to the instability of the front, which leads to the separation of the head of the streamer into two parts. The second mechanism is associated with the instability of the streamer in the base region, which leads to the branching of the streamer with the formation of a large number of lateral streamers closing the main channel of the streamer to the cathode. In numerical experiments, the third branching mechanism observed in experiments connected with the branching of the plasmoid in the cathode region with the closure of the space charge to the anode through the streamer system was observed. The results of modeling the evolution of globular clusters in a scale of hundreds of milliseconds are given. Plasma exchange recharge modes leading to the formation of a positive or negative charge of the system are found
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01.00.00 Physical-mathematical sciences
DescriptionMovement of geographical and magnetic poles versus celestial bodies’ positions is examined on the basis of the special and general relativity theory.
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A MODEL FOR MINORITY CARRIER MOBILITY IN POLYSILICON EMITTERS
01.00.00 Physical-mathematical sciences
DescriptionA model for minority carrier mobility in polysilicon emitter contacts is developed. It is based on the effect of the segregation of electrically active dopants to polysilicon grain boundaries and the thermionic emission - diffusion theory of the hole current. An analytical equation is derived which allows to calculate hole mobility in polysilicon emitter contacts and its dependence on dopant concentration and polysilicon grain size
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01.00.00 Physical-mathematical sciences
DescriptionThe article examines the historical aspect of the appearance of the concept of the photon, which was introduced through the works of Planck, Einstein, Compton, Lewis. It is noted that the photon has both corpuscular characteristics (momentum, mass, energy) and wave (frequency, wavelength), which are interconnected. Thus, the photon has dual properties – of a particle and a wave. The article deals with the analysis described in the literature of the photon model proposed by S.M. Polyakov and O.S. Polyakova, F.M. Konarevym-Krauzerom, V.G.Kozlovym and S.I. Chervyakov, as well as with their advantages and disadvantages. A version of the model in the form of a photon of two identical but oppositely charged halfmass, which simultaneously perform translational, rotational and vibrational motion was suggested. We have shown derivation of the amplitude of vibration of the two half-mass photon connected with simple relation with wavelength, described with this photon. On this basis, it is concluded that the state of a photon is characterized by a rotational movement of its oppositely charged half-stuff, which radius (r) is the amplitude of the oscillation process of each of the half-mass, and described by oppositely charged half-mass circumference length S in expanded form in a result of the progressive movement is the length wave l. This work displays the wave equation describing the motion of photons in the form of a standing wave which is a complete analog-independent Schrödinger equation for the motion of an electron in a hydrogen atom
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01.00.00 Physical-mathematical sciences
DescriptionThe method of ordinary least squares (OLS) is widely known and deservedly popular. However, some attempts to improve this method. The result of one of such attempts is the weighted least squares (WMNC), the essence of which is to give the observation a weight which is inversely proportional to the errors of their approximation. Thereby, in fact, monitoring is ignored the more the difficult to approximate it. The result of this approach, formally, is the approximation error decreasing, but in fact, this occurs by partial refusal to consider the "problem" of observations, making a big mistake. If the idea underlying WMNC to bring to the extreme (and absurd), then in the limit, this approach will lead to the fact that from the entire set of observations there will be only those that lie almost exactly on the trend obtained by the method of least squares, and the rest will simply be ignored. However, according to the author, it's not a problem, and the failure of its decision, though it might look like a solution. In the work we have proposed a solution, based on the theory of information: to consider the weight of observations, the number of the argument of the value function. This approach was validated in the framework of a new innovative method of artificial intelligence: methods for automated system-cognitive analysis (ASA-analysis) and implemented 30 years ago in its software toolkit, which is "Eidos" intelligent system in the form of so-called "cognitive functions". This article presents an algorithm and software implementation of this approach, illustrated in detailed numerical example. In the future it is planned to give a detailed mathematical basis of the method of weighted least squares, which is modified by the application of information theory to calculate the weights of the observations, and investigate its properties
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01.00.00 Physical-mathematical sciences
DescriptionThis article briefly discusses the mathematical nature of the author's proposed modification of the weighted least squares, in which the amount of the data is used as the weights of observations. There are two variants of this modification. In the first one, the weighting of the observations was made by replacing one observation with a certain amount of the information in it by the corresponding number of observations for unit weight, and then we applied the standard method of least squares. In the second method, the weighting of the observations was performed for each value of the argument by replacing all observations with a certain amount of information in one observation of unit weight which had been obtained as a weighted average of them, and then we applied the standard method of least squares. We have described in detail the technique of numerical calculations of the amount of information in the observations, based on the theory of automated system-cognitive analysis (ASC-analysis) and implemented it with a help of software tools - intelligent system called "Eidos". The article provides an illustration of the proposed approach on a simple numerical example. In the future, we are planning to give more detailed mathematical basis of the method of weighted least squares, which is modified by using the amount of information as weights, but also to explore its properties
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01.00.00 Physical-mathematical sciences
DescriptionAdequate and effective assessment of the efficiency, effectiveness and the quality of scientific activities of specific scientists and research teams is crucial for any information society and a society based on knowledge. The solution to this problem is the subject of scientometrics and its purpose. The current stage of development scientometrics differs greatly from his previous appearance in the open as well as paid on-line access to huge amount of detailed data on a large number of indicators on individual authors and on scientific organizations and universities. The world has well-known bibliographic databases: Web of Science, Scopus, Astrophysics Data System, PubMed, MathSciNet, zbMATH, Chemical Abstracts, Springer, Agris, or GeoRef. In Russia, it is primarily the Russian scientific citing index (RSCI). RSCI is a national information-analytical system, accumulating more than 9 million publications of Russian scientists, as well as the information about citation of these publications from more than 6,000 Russian journals. There is too much information; it is so-called "Big data". But the problem is how to make sense of these large data, more precisely, to identify the meaning of scientometric indicators) and thus to convert them into great information ("great information"), and then apply this information to achieve the objective of scientometrics, i.e. to transform it into a lot of knowledge ("great knowledge") about the specific scientists and research teams. The solution to this problem is creating a "Scientific smart metering system" based on the use of the automated system-cognitive analysis and its software tools – an intellectual system called "Eidos". The article provides a numerical example of the creation and application of Scientometric intelligent measurement system based on a small amount of real scientific data that are publicly available using free on-line access to the RSCI
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THE HIGHER ASYMPTOTIC EXPANSIONS FINDING FOR BOUNDARY VALUE PROBLEM OF THE ZOM MODEL
01.00.00 Physical-mathematical sciences
DescriptionIn this article authors propose the asymptotic solution of the boundary value problem modeling the transport of salt ions in the cell electrodialysis desalination unit. The domain of the camera desalting broken into two subdomains: electroneutrality and space charge. Subdomains has own asymptotic expansion. The subdomain of the space charge has unique solvability of the current approach used by the solvability condition of the next approximation
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MODELS OF NEURONET INFLATION IN RUSSIA
01.00.00 Physical-mathematical sciences
DescriptionThe article’s conclusion is that for adequate and effective inflation modeling in Russia by means of modern neuronet technologies it is necessary to consider tendencies of economic development. For training and forecast, it is necessary to use only those periods of time within the limits of which identical economic tendencies work. The article uses modern tool means, such as neuronet, which is offered to technology, for approximation and forecasting of rates of inflation