№ 133(9), November, 2017
Public date: 30.11.2017
Archive of journal: Articles count 94, 254 kb
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01.00.00 Physical-mathematical sciences
TO THE QUESTION OF MATHEMATICAL MODELS OF MATERIAL FLOW MANAGEMENT
01.00.00 Physical-mathematical sciences
Description
The article concentrates on the matters of current interest in the sphere of product flows. The object of research is the relocation of product flows from the supply sphere, represented by supply and sales organizations or other commercial-intermediary agencies, to the sphere of business enterprise. The ultimate goal of the production and economic system modeling is the preparation for managerial decision-making. The choice of the model depends on the purposes of the modeling, management functions, automation manufacturing step, applied mathematical tools technique. The article considers the main characteristics of the flow, which while retaining their individuality at the same time depend on each other and function logically in the economic space. The advantages and disadvantages of the material inventory and flows management in micrologistic intraproductive systems are being analyzed. External and internal environment, taken as a basis for the real logistical process modeling, determine the type of the principal stock regulation system and the type of the corresponding mathematical model. Methods and models of the stock theory, the primary objective of which is to determine the most important incoming product flow parameters of the system, are still in demand and their primary goal is to adapt the manufacturing company to the consumers’ needs
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01.00.00 Physical-mathematical sciences
Description
The article is dedicated to a numerical investigation of a plane problem of the oscillation amplitude of a buried source, depending on the frequency and motion speed in various isotropic media. Three types of the medium are considered: a two-layer package with a rigidly fixed base, a two-layer package with a mechanically free base, a half-space. The source, in the form of a stress jump simulating a rigid inclusion of small dimensions, moves in the interface plane at a constant speed. Homogeneous boundary value problems are considered in a moving coordinate system associated with a source. The solution method is based on the usage of integral Fourier transforms, the method of direct contour integration and algorithms for constructing symbols of Green's matrices. The method of direct contour integration significantly simplifies calculations in comparison with the traditional approaches to the calculation of Fourier integrals. We have presented calculations of nine amplitude-frequency and amplitude-velocity characteristics for different combinations of medium and source types, that give an exhaustive qualitative and quantitative description of the solutions for boundary value problems in a wide range of velocities and frequencies. Comparative analysis of calculations showed a primary influence of the type of an elastic medium on the investigated characteristics, as well as the large influence of the source type. Which, in turn, revealed some substantial connections between the boundary value problems with a moving source and the corresponding problems with a stationary source
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THE LIMIT THEORY OF THE SOLUTIONS OF EXTREMAL STATISTICAL PROBLEMS
01.00.00 Physical-mathematical sciences
Description
Many procedures of applied mathematical statistics are based on the solution of extreme problems. As examples it is enough to name methods of least squares, maximum likelihood, minimal contrast, main components. In accordance with the new paradigm of applied mathematical statistics, the central part of this scientific and practical discipline is the statistics of non-numerical data (it is also called the statistics of objects of non-numerical nature or non-numeric statistics) in which the empirical and theoretical averages are determined by solving extreme problems. As shown in this paper, the laws of large numbers are valid, according to which empirical averages approach the theoretical ones with increasing sample size. Of great importance are limit theorems describing the asymptotic behavior of solutions of extremal statistical problems. For example, in the method of least squares, selective estimates of the parameters of the dependence approach the theoretical values, the maximum likelihood estimates tend to the estimated parameters, etc. It is quite natural to seek to study the asymptotic behavior of solutions of extremal statistical problems in the general case. The corresponding results can be used in various special cases. This is the theoretical and practical use of the limiting results obtained under the weakest assumptions. The present article is devoted to a series of limit theorems concerning the asymptotics of solutions of extremal statistical problems in the most general formulations. Along with the results of probability theory, the apparatus of general topology is used. The main differences between the results of this article and numerous studies on related topics are: we consider spaces of a general nature; the behavior of solutions is studied for extremal statistical problems of general form; it is possible to weaken ordinary requirements of bicompactness type by introducing conditions of the type of asymptotic uniform divisibility
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BAER’S LAW AND EINSTEIN’S VORTEX HYPOTHESES
01.00.00 Physical-mathematical sciences
Description
We consider numerical solutions of the Navier-Stokes equations describing laminar and turbulent flows in channels of various geometries and in the cavity at large Reynolds numbers. An original numerical algorithm for integrating a system of nonlinear partial differential equations is developed, based on the convergence of the sequence of solutions of the Dirichlet problem. Based on this algorithm, a numerical model is created for the fusion of two laminar flows in a T-shaped channel. A new mechanism of meandering is established, which consists in the fact that when the two streams merge, a jet is formed containing the zones of return flow. Vortex motion in a rectangular cavity is studied. It is established that the numerical solution of the problem with discontinuous boundary conditions loses stability at Reynolds number Re> 2340. The trajectories of passive impurity particles in a cylindrical cavity are investigated. An explanation of the behavior of tea leaves in a cup of tea in the formation of a toroidal vortex because of circular stirring is confirmed, which is confirms the wellknown hypothesis of Einstein. A numerical model of flow in an open channel with a bottom incline in a rotating system is developed. It is shown that in both laminar and turbulent flow under certain conditions a secondary vortex flow arises in the channel due to the Coriolis force, which explains the well-known Baer law and confirms the Einstein hypothesis
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INTERRELATION OF THE MODEL OF CALCULATIONS OF ATOMIC RADIUS AND VARIOUS SYSTEM CHARACTERISTICS
Description
In this article, we discuss the relationship between the previously obtained model for calculating atomic radii with electrodynamics, the hydrodynamic model of the planets of the Solar System, and the R-function of the structural organization of electronic systems. It is shown that the curve of the dependence of the value of the correction coefficient e x on the atomic number of the element in form coincides with the dependence of the ionization energy on the mass of the atom and the R-function on the nuclear charge. The concept of the "atomic nucleus potential", which takes into account the energy of the nucleus and the charge of the nucleus of the atom, is introduced. It is shown that the radius of an atom is the product of the nuclear potential by a factor kx , taking into account the characteristics of electronic levels; the energy of the nuclear reaction is the work of the forces of the field (potential) of the atomic nucleus along the displacement of the atomic charge. The dependence of the potential of the nucleus on the charge number in the Mendeleev’s Periodic Table is shown. It is shown that any system of satellites (or atomic shells) has a constant ratio of its Kepler number to the mass of the central body around which they rotate. It is shown that in the Table of Mendeleev's chemical elements and in the solar system, the fundamental value is the mass of the center (the nucleus of the atom or the center of the orbit). The ratio of the Kepler number to the mass of the central body is a constant, within the accuracy of construction and calculations
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Description
The study of agronomy plants history, its distribution and use through image analysis and iconography have been presented. As an object of study, the image of wheat has been taken as the ancient culture of the world among agricultural plants. After many years, the illustrative series takes on a completely different meaning, namely, it becomes an independent resource of information. The analysis includes images of wheat in painting, sculpture, mosaic, tapestries, murals, botanical illustrations, stamps, porcelain and scientific drawings. In the work, we have made an attempt to analyze the images of wheat in the works of art in order to search for species diversity, directions of selection and genetic research, and also to present the morphological characteristics of culture. The method of analysis is a method of visual notes or sketches, which consists in comparing and searching information by image. The analysis is carried out on grounds: tall wheat, multiflorous forms of wheat, nonspreading, thickness of straw. The visual analysis of the images of wheat in works of art by the method of sketches made it possible to reveal the species diversity of culture along the ear, to see the ancient forms that were cultivated in the world before the "green revolution". The analysis included works of art from the 14th to the 21st century, the masters of painting in Italy, Germany, Russia, the Netherlands, France, the United States, and others
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DESIGN OF THERAPEUTIC PHAGE COCKTAILS BASED ON T4-TYPE BACTERIOPHAGES: ADVANTAGES AND DISADVANTAGES
Description
In the review, the stages of designing therapeutic cocktails of T4 type bacteriophages based on works by Harald Brüssow from Nestlé S.A. (Switzerland) are considered. The main stages of this process are identified: analysis of existing cocktails, selection of phages; creating a collection; cultivation of the host bacterium, multiplication of viruses; purification of the preparation; contamination testing; preservation, stabilization and storage; preclinical and clinical trials. H. Brüssow first studied the Russian drug " Coli-Proteus bacteriophage " of "Microgen" with the help of metagenomic analysis, electron microscopy and conducted its clinical studies. Prof. Brüssow considered the advantages of T4 bacteriophages for the treatment of Escherichia coli infections. Researchers studied methods of cultivation in Erlenmeyer flasks, in a bioreactor, in disposable sack cultivators for the propagation of viruses. For its purification the chromatography, centrifugation, filtration and polyethylene glycol precipitation were studied. To quickly check the contamination of phage cocktails, a mass spectrometry method is proposed. Researchers considered basic strategies, such as lyophilization, spray drying, the formation of microcrystals and microspheres to stabilize the preparations. They also reviewed the results of clinical trials of phage cocktails. We have listed the problems of selecting T4 bacteriophages from the point of view of modern knowledge. H. Brüssow and his colleagues carried out an interesting work on the construction of phage cocktails based on T4 type bacteriophages, and also revealed the problems of the current state of phage therapy
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Description
In the course of the work, 33 ISSR markers were evaluated for efficacy in the detection of genetic changes in regenerants of Galanthus woronowii Losinsk.. Ten markers were found suitable for genotyping according to the species under study. Five samples from the selected ten were analyzed for a sample of 20 plants of regenerants and a mother plant. The obtained data testify to genetic stability of plant material in the process of microclonal propagation
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SIMULATION OF A POWER TRANSFORMER WORK WITH A HIGH LEVEL OF HIGHER HARMONICS
Description
The importance of improving the quality of electrical energy was growing along with the development and wide implementation in the production of valve converters and various highperformance processing units, such as arc furnace, welding machines etc. The main causes of potential and existing non-compliances of non-sinusoidal voltages can be joining sources and non-sinusoidal reactive power sources, including resonant filters, to existing electric grids without taking into account their possible impact on the distortion of the sinusoidal voltage. Transformers are affected by the non-sinusoidal shapes of the curves of current and voltage. The effect is characterized by the fact that the harmonics of current and voltage increase transformer temperature, compared to purely sinusoidal current and voltage. The aim of this work is to study the influence of higher harmonics on power loss in power transformers. Experimental study of operation of power transformers was carried out on the developed model of the transformer substation. The experiments were conducted with different capacities of transformers that have variables in the range of 250-1000 kVA. By using programmable voltage source a sinusoidal voltage is formed containing the third, fifth, sixth, seventh, ninth and twelfth harmonics. The level of harmonics is changed in the range of 2-12 %
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A SURFACE RUNOFF CLEANING PLANT FOR THE TERRITORY OF THE NOVOROSSIYSK SEA PORT
Description
The article considers scheme of sewage treatment plants AG-STOK of Novorossiysk trading sea port, designed to clean the surface runoff from the territory of industrial sites and residential areas to the norms of discharge in the drainage network. The installation includes a well-separator, a storage tank, mechanical cleaning of solids on a mechanical filter, filtration through a filter with granular loading and filtration through a filter with sorption loading. The treated runoff, which corresponds to the conditions of discharge into the urban drainage network, accumulates in a tank of clean water and is diverted to the storm sewer network. There are: the scheme of treatment facilities, the explication of equipment, a photo of a mechanical filter, a filter with a granular load and a filter with a sorption load. The indicators of surface runoff correspond to the norms of the maximum permissible discharge
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