scholarly journals Probabilities of Atomic Departures from the Slit System

2021 ◽  
Vol 248 ◽  
pp. 01023
Author(s):  
Leonid Pletnev
Keyword(s):  
Gas Flow ◽  
Open Systems ◽  
Computer Experiments ◽  
Complex Problem ◽  
Theoretical Description ◽  
Point Of View ◽  
Atomic Collisions ◽  
Single Collision ◽  
Mathematical Problems ◽  
Molecular Mode

The theoretical description of experimental data on transport in open systems has been of interest for more than a hundred years. Boltzmann proposed a new view of the transfer of matter. Now it is possible to describe the transfer processes from a microscopic point of view. The solution of the Boltzmann equation and the equations derived from it is a complex problem related to the mathematical problems of solving such equations. On the other hand, the complexity of the solution is related to the geometry of the system in which the transfer process takes place. Fundamental physical calculations are made for systems: flat, slotted, cylindrical, rectangular, etc. In the free molecular mode of gas flow, collisions of molecules occur mainly with the walls of systems. In this connection, there was a direction related to the calculation of the probabilities of atomic transport in the system. In this paper, we propose an approach for determining the probabilities of atomic outcomes from slit systems depending on the relative height of the walls of H systems. Exact formulas are obtained for calculating the probabilities of atomic departures from systems without colliding with walls, the distribution of atomic collisions over the height of the system wall, the probabilities of atoms entering the condensed phase after a single collision with the system walls, and the probabilities of atomic departures from systems after a single collision with walls. The accuracy of the obtained formulas was compared with the data obtained from computer experiments using the Monte Carlo method.

scholarly journals Modeling and theoretical description of magnetic hybrid materials—bridging from meso- to macro-scales

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Andreas M. Menzel ◽  
Hartmut Löwen
Keyword(s):  
Colloidal Particles ◽  
Colloidal Particle ◽  
Theoretical Description ◽  
Point Of View ◽  
Material Behavior ◽  
Theoretical Point ◽  
Mechanical Stiffness ◽  
Theoretical Approaches ◽  
Theoretical Predictions ◽  
Particle Level

Abstract Magnetic gels and elastomers consist of magnetic or magnetizable colloidal particles embedded in an elastic polymeric matrix. Outstanding properties of these materials comprise reversible changes in their mechanical stiffness or magnetostrictive distortions under the influence of external magnetic fields. To understand such types of overall material behavior from a theoretical point of view, it is essential to characterize the substances starting from the discrete colloidal particle level. It turns out that the macroscopic material response depends sensitively on the mesoscopic particle arrangement. We have utilized and developed several theoretical approaches to this end, allowing us both to reproduce experimental observations and to make theoretical predictions. Our hope is that both these paths help to further stimulate the interest in these fascinating materials.

scholarly journals The system of chemical and mathematical problems as a tool for the development of motivation of students of technical universities

2019 ◽  
Vol 69 ◽  
pp. 00052
Author(s):  
Galiya Igtisamova ◽  
Zemfira Yangirova ◽  
Doniyor Nosirov ◽  
Aydar Yangirov
Keyword(s):  
Student Learning ◽  
Empirical Data ◽  
Point Of View ◽  
Learning Motivation ◽  
Self Development ◽  
Creative Personality ◽  
Mathematical Problems ◽  
Personal Approach ◽  
Level Of Motivation ◽  
Development Of Students

The research relevance is connected with the orientation of the modern model of education towards the formation of a competitive creative personality, with the need for constant self-improvement and self-development. It should be noted that the effectiveness of student learning is largely determined by the level of motivation, interest and personal participation of subjects. Therefore, the article is aimed at disclosing mechanisms for the development of students' learning motivation through a system of differentiated tasks. The leading approach to study of a problem was a personal approach, the purpose of which is to identify the issue under discussion from the point of view of dialogism, subjectivity and individuality. This document presents the characteristics of the developed and tested system of differentiated problems of mathematics, focused on the development of student learning motivation, as well as the provision of empirical data on the results of implementation. It also describes the principles on which we defined three levels of tasks in mathematics: “palgorithms”, “tasks of finding tasks” and “creative tasks”.

scholarly journals MATHEMATICAL MODELING AND CALCULATION OF GAS DYNAMIC CHARACTERISTICS OF FREE THERMAL AIR VORTEX

2017 ◽  
pp. 93-98
Author(s):  
D. D. Barannikova ◽  
A. G. Obukhov
Keyword(s):  
Gas Flow ◽  
Local Heating ◽  
Three Dimensional ◽  
Vertical Cylinder ◽  
Point Of View ◽  
Underlying Surface ◽  
Heat Conducting ◽  
Gas Dynamics Equations ◽  
Viscous Heat ◽  
Flow Formation

The article analyzes experimental and analytical studies of ascending swirling air flows. In experimental works such flows are considered from the point of view of the direction of twist, the thermal regimes of heating the underlying surface, the estimation of integral parameters, the method of influence on them, and various methods of visualization. In analytical papers, by constructing solutions of the system of gas dynamics equations, the emergence of a twist of the corresponding direction is proven when there is a gas flow into a vertical cylinder of nonzero radius. In addition, in the numerical modeling of thermal ascending swirling flows, a feature was observed in the behavior of a moving gas at the initial moments of flow formation when the underlying surface was heated locally. This feature consists in the appearance on the boundary of the heating region of counter propagating gas flows with opposite directions of twist. The paper presents the results of numerical simulation of three-dimensional unsteady flows of a compressible viscous heat-conducting gas in thermal swirled vortices with local heating of the underlying surface, taking into account the action of gravity and Coriolis forces.

Analytic program derivation in type theory

1998 ◽  
Author(s):  
Petri Mäenpää
Keyword(s):  
Mathematical Method ◽  
Problem Solving ◽  
Type Theory ◽  
Mathematical Problem ◽  
Geometric Analysis ◽  
Algebraic Method ◽  
Point Of View ◽  
Program Derivation ◽  
Mathematical Problems ◽  
The Given

This work proposes a new method of deriving programs from their specifications in constructive type theory: the method of analysis-synthesis. It is new as a mathematical method only in the area of programming methodology, as it is modelled upon the most successful and widespread method in the history of exact sciences. The method of analysis-synthesis, also known as the method of analysis, was devised by Ancient Greek mathematicians for solving geometric construction problems with ruler and compass. Its most important subsequent elaboration is Descartes’s algebraic method of analysis, which pervades all exact sciences today. The present work expands this method further into one that aims at systematizing program derivation in a heuristically useful way, analogously to the way Descartes’s method systematized the solution of geometric and arithmetical problems. To illustrate the method, we derive the Boyer-Moore algorithm for finding an element that has a majority of occurrences in a given list. It turns out that solving programming problems need not be too different from solving mathematical problems in general. This point of view has been emphasized in particular by Martin-Löf (1982) and Dijkstra (1986). The idea of a logic of problem solving originates in Kolmogorov (1932). We aim to refine the analogy between programming and mathematical problem solving by investigating the mathematical method of analysis in the context of programming. The central idea of the analytic method, in modern terms, is to analyze the functional dependencies between the constituents of a geometric configuration. The aim is to determine how the sought constituents depend on the given ones. A Greek analysis starts by drawing a diagram with the sought constructions drawn on the given ones, in the relation required by the problem specification. Then the sought constituents of the configuration are determined in terms of the given ones. Analysis was the Greeks’ method of discovering solutions to problems. Their method of justification was synthesis, which cast analysis into standard deductive form. First it constructed the sought objects from the given ones, and then demonstrated that they relate as required to the given ones. In his Geometry, Descartes developed Greek geometric analysis-synthesis into the modern algebraic method of analysis.

scholarly journals A methodology for the professional training of the management and evaluation of HPC systems

2018 ◽  
Vol 8 (1) ◽  
pp. 68-79
Author(s):  
Jarmila Skrinarova ◽  
Adam Dudas
Keyword(s):  
Professional Training ◽  
Job Scheduling ◽  
Complex Problem ◽  
Point Of View ◽  
System Management ◽  
Specific Content ◽  
Scientific Project ◽  
Job Scheduling Problem ◽  
Using Data ◽  
New Education

Abstract The paper is motivated by critical demand for experts and scientists working in areas of mathematical modeling, simulations, big data techniques and who are familiar with management of HPC systems from user and administrator point of view. We created a new course entitled “HPC system management”. Our goal is focused on students to provide them with knowledge and understanding of complex problem of the HPC system management concerning job scheduling. Important fact is that the job scheduling problem is an NP-complete problem. Next objective of our course is to educate skilled experts, who are able to design and implement programs, scripts and models doing job management to solve specific parts of this complex problem. The course is innovative from several points of view. Our new approach lies in specific content, which is oriented to the HPC system management in contrast to existing courses, which are usually focused on development of HPC applications. Also we developed and provide new education methodology in a form of scientific project, which decomposes the complex problem into subproblems and subsequently brings together solutions to the subproblems to form united model. New education methodology is focused on generation of (pseudo-) optimal jobs schedule using data from real systems. The huge volume of used data leads to ideas and methodologies of problem solving, which are suitable for problems not solvable in polynomial time. Educational methodology also contains implementation of a job scheduling simulator. The paper presents a pilot course, in which students explore various scheduling algorithms and research their properties with the use of data gained from NorduGrid

scholarly journals Theoretical Assessment of Thermodynamic Stability in Nanocrystalline Metallic Alloys

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3408 ◽  
Author(s):  
Antonio Mario Locci
Keyword(s):  
Thermodynamic Stability ◽  
Theoretical Description ◽  
Point Of View ◽  
Theoretical Point ◽  
Qualitative Comparison ◽  
Theoretical Approaches ◽  
Model Predictions ◽  
Cr System ◽  
Experimental Findings ◽  
Theoretical Assessment

Thermal stability in nanocrystalline alloys has been extensively explored while using both experimental and theoretical approaches. From the theoretical point of view, the vast majority of the models proposed in the literature have been implicitly limited to immiscible or dilute systems and thus lack the necessary generality to make predictions for different alloying interactions and in the case of intermetallic compounds formation. In this work, a general theoretical description for the case of binary W-based alloys is presented. It is shown that a critical value Ω ∗ of the interaction energy in the grain boundary Ω ( g b ) exists, such that the condition Ω ( g b ) < Ω ∗ can be regarded as a criterion for thermodynamic stability assessment. A procedure for calculating the value of Ω ∗ for each specific alloy is illustrated. A preliminary qualitative comparison between the model predictions and properly selected experimental findings taken from the literature and related to the W-Cr system is also provided.

scholarly journals Kloning as selektiewe voortplanting: ’n Voorlopige teologies-etiese beoordeling

2000 ◽  
Vol 34 (4) ◽  
Author(s):  
A.L. Rheeder ◽  
P.J. De Bruyn ◽  
J.H. Van Wyk ◽  
N.T. Malan
Keyword(s):  
Human Embryo ◽  
Significant Degree ◽  
Complex Problem ◽  
Point Of View ◽  
Reproductive Choice ◽  
Ethical Assessment ◽  
The Bible ◽  
Christian Couples ◽  
Ethical Point ◽  
Final Answer

Cloning as selective reproduction: A preliminary theological-ethical assessment Although a significant degree of doubt about cloning initially existed, it is a well-known fact that cloning has successfully been applied in mammals. It is, therefore, not strange that some couples are indeed interested in this procreation option – especially since a human embryo has already been created in this way. This article thus attempts to evaluate cloning as a reproductive choice for Christian couples in the light of the view of marriage and reproduction expressed in the Bible. However, from a theological-ethical point of view, the answer given in this article should be seen as merely provisional as cloning is an extremely recent phenomenon. As such, academics should be careful not to be too hasty in giving a final answer to this very complex problem.

PRINCIPLES OF SUSTAINABLE SPATIAL NONEQUILIBRIUM

2018 ◽  
Vol 3 (2) ◽  
Author(s):  
A. A. Kaganovich ◽  
S. P. Prisyazhnyuk ◽  
A. S. Prisyazhnyuk ◽  
A.A. Petrov
Keyword(s):  
Open Systems ◽  
Point Of View ◽  
Self Organization ◽  
Nonequilibrium Systems ◽  
Ongoing Research ◽  
Evolutionary Changes ◽  
Self Development ◽  
Development Processes ◽  
Multi Level ◽  
Equilibrium Economic

<p>On the basis of ongoing research and development the authors substantiate the need to improve the theoretical and methodological foundations of self-development processes for equilibrium and non-equilibrium economic multi-level systems.Particular attention is paid to the analysis of the functioning of the so-called «microscopic open nonequilibrium systems»</p><p>In the article, the economic system is viewed from the point of view of synergy - as dual entities consisting of a continuous and discrete sphere.Classification of possible evolutionary changes in the kinetic and constitutional spheres in the process of self-development for economic equilibrium and nonequilibrium systems.Particular attention is paid to the continuous self-organization of microscopic open systems.</p>

Russian Scanners for Eddy Current Testing of Drilling Pipe Elements in the Oil and Gas Industry

NDT World ◽  
2020 ◽  
pp. 5-8
Author(s):  
Aleksandr Kazachenko
Keyword(s):  
Control Charts ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Complex Problem ◽  
Point Of View ◽  
Destructive Testing ◽  
Gas Industry ◽  
Shewhart Control ◽  
Inspection Process ◽  
Composite Pipes

Composite materials appear to be an ideal solution to a complex problem with conflicting conditions: how to simultaneously obtain sufficient strength, reliability and durability of the structure, while providing the minimum possible mass of it. However, non-destructive testing of products from them raises more and more questions. In the mass production of composite pipes for pipelines, the only possible option from the point of view of ensuring the necessary reliability, information capacity of the results of the performed inspection of products and productivity is the automation of the inspection process, which includes special methods for identifying defects. Statistical methods, including capability ratio and Shewhart control charts, should be used to estimate the error in determining the size of defects.

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