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For the numerical solution of the boundary value problem of convective heat transfer in a ladle while blowing steel argon proposed finite-difference approximation of the original mathematical model of convective heat transfer in a continuous divergence form. Used stable and economical implicit monotone conservative difference scheme. 1. Берковский Б. М., Ноготов Е. Ф. Разностные ...

Compact presentations for solution of the generalized Padè problem are presented, that have been known only for the Padè problem (so called compact Nutall presentation). Using them determinant presentations for the approximants [M – 1 / M], [M / M] и [M / M – 1] were obtained. 1. Бейкер Дж. мл., Грейвс-Моррис П. Аппроксимации Паде. M., 1986. 2. Stoer J., Bulirsch R. Introduction to numerical analysis. New York, 1992....

... work the problem of electron bound to 3d linear atom chain scattering on impurity atoms is considered. In order to describe zone electrons the Bloch functions are constructed with respect to symmetry consideration. In addition, zero range potential approximation is used to model both atoms in chain and impurity atoms. Botman S. A., Leble S. B. Bloch wavefunction, scattering, impurity, zero range potential 29-34

Differences methods of the approximate solution of the two-dimensional equation of ions diffusion with the mixed derivatives and the first derivatives of a divergent look are considered. Test calculations on a modeling task with the known analytical decision are carried out. Operability ...

... pairs for higher-dimensional evolution PDE’s and a 3+1 dimensional integrable generalization of the Burgers equation // Proc. Amer. Math. Soc. 2007. 135. P. 731—741 [ArXiv:nlin. SI/0411061]. Yurova A. A. bottom current, boundary layer approximation, Painlevé criterion. 42-48 10.5922/2223-2095-2009-4-9

In this note we study the problem of a function reconstruction in a con­text of a Laplace method application. We use a unitary space of splines with a double dimension of one, that approximate the set of points, representing the results of observation. The conventional scalar product allows to project the approximation onto the subspace of observations. The use of the same scalar product yields the norm that we use to estimate error ...

An approximate solution of the problem of the structure and characteris­tics of a stationary nonlinear periodic wave on the surface of a liquid of finite depth has been obtained. The solution is as follows: first, the kinematic and dynamic conditions are ...

... contrast-enhanced ultrasound. The most important factors affecting the results of liver stiffness measurements include using SWE method, the diagnostic equipment and the sensors, the measurement depth and acoustic access; the reliability of various SWE methods is approximately equivalent. Among modern ultrasonic SWE technologies, the most efficient to visualize the measurement area are ARFI technologies — point shear wave elastography (pSWE) and two-di­men­sional shear wave elastography (2D-SWE). Two-dimensional ...

... peculiar character. The most vibrant and attractive areas of the suburbs are located at a distance of 14—32 km from the centre of Saint Petersburg, between the isochrones of forty- and ninety-minute transport accessibility. Lying at a distance of approximately 60 km from the city centre, the two-hour travel time band marks the border of both the commuter zone and the Saint Petersburg agglomeration. A new settlement system is emerging within the suburban area of Saint Petersburg — the most economically,...

... above properties, often this is the stability property of the solution with re­spect to initial conditions. The solution of such problems is sensitive even to a small change in the values of the input data, and so we do not guarantee an acceptable approximation to the answer at the level of the existing error in the measurement of initial values. The paper discusses the use of the instability ef­fect for the synthesis of cryptographic transformations using natural noise in radio channels. ...

The article describes numerical modelling of fluctuations of an aerosol column in pipes at resonant frequencies. The author suggests a mathematical model of dynamics of the heterogeneous medium-mix with approximately equal component mass fractions. The mathematical model suggests the solu­tion of a dynamics equation system for each of the mix component. The carrier medium is a viscous, compressible, heat-conducting gas. The dispersed com­ponent of ...

... reasoning and activating the visual-figurative reasoning of users. The use of such systems in the practice of solving problems, in particular when managing regional electric networks, will allow users to «see» the problem situation and its possible approximate solutions, which can subsequently be justified and refined by the methods of logical-mathematical reasoning. 1. Medsker L. R. Hybrid Intelligent Systems. Boston, 1995. 2. Колесников А. В. Гибридные интеллектуальные ...

... which is an urgent task for clinical medicine. It is directly connected to the need for an objective quantitative assessment of organ size. The complexity of calculating the volume is due to an irregular geometric shape of the organ, which can not be approximated to an ellipse or any other geometric figure. The aim of the study is to ex vivo evaluate the possibilities of measuring the volume of the liver based on the linear dimensions of the organ according to the formulas proposed for ultrasonic ...

... can be neglected. The boundary value problem is solves with the standard numerical method, the Mathcad in particular. The least squares method was used to find the empirical dependence of the heat nitrogen on the temperature. Third order polynomial approximation gives the average deviation from experimental data of less than 0.5 %. The paper also shows that with increase of the wall temperature of channel increases the required pressure at the inlet of the lance and the speed of the output. The ...

... horizontal neutral wind and plasma heating by superthermal electrons. The article presents numerical calculation results of variations of charged particles concentration in the ionosphere and the plasmasphere. The comparative analysis of various hydrodynamic approximations for the description of the ionospheric and the magnetospheric plasma is carried out. It is made on the basis of the numerical solution of the system of equations of energy, continuity and motion for O+, H+ ions and electrons along a power ...

The work of analog-to-digital converter and the problems arising in the reduction of the input signal are investigated. A solution to the problem of aperture uncertainty is presented by using a constructive method with an approximate analysis of the reconstructed signal. 1. Балакай В. Г., Крюк И. П., Лукьянов Л. М. Интегральные схемы аналого-цифровых преобразователей. М., 2008. 2. Гельман ...

... problem: II. Polyhedral results // Ibid. 1995. Vol. 25. P. 199–216. 5. Focacci F., Lodi A., Milano M. A hybrid exact algorithm for the TSPTW // INFORMS Journal on Computing. 2002. № 14 (4). Р. 403—417. 6. Bar-Yehuda R., Evenb G., Shahar S.(M.) On Approximating a Geometric Prize-Collecting Traveling Salesman Problem with Time Windows // Journal of Algorithms. 2005. April. P. 76–93. Muzychin V. freight rail transportation, combinatorial optimization, database, railways graph, mathematical modeling ...

... components of the velocity and pressure. It is noted that it will generalize the problem under consideration in the event of a multi-layer liquid. The results, including the dispersion relation, fully consistent with the known. Specially considered long-wave approximation. 1. Сретенский Л. Н. Теория волновых движений идеальной жидкости. М., 1977. Zaitsev A., Kulakov P. homogeneous ideal fluid, a new method of studying of sinusoidal waves, horizontal ...

... колебаниях многослойной вращающей жидкости // Физика атмосферы и океана. 1967. Т. 111, № 3. С. 284—290. Zaitsev A., Kulakov P. two-layer liquid, sinusoidal waves, dispersion relations, Boussinesq approximation, phase velocity of short and long waves, new technique 32-43

... finite-differential scheme for solution of the cross convection-diffusion equations within models of the Rayleigh — Taylor instability in the equatorial region of the Earth ionosphere is considered. For test problems the experimental value of the approximation order of the offered method of non-linear correction of the finite-differential scheme for different types of limiters is received numerically. 1. Гайдуков В. Ю., Кащенко Н. М., Мациевский С. В. и др....

For describe the hydrodynamic and thermal processes in the ladle in the time of blowing argon Steel developed a mathematical model of convective heat transfer in the Boussinesq approximation. We give a statement of the problem of this description, the translation model in dimensionless criterial form diver-gent representation in the form (Θ, ω, Ψ)-system. 1. Берковский Б. М., Ноготов Е. Ф. Разностные ...

... Современные информационные технологии и ИТ-образование : матер. III Международной научно-практической конференции. М., 2008. 9. Mamdani Е. Н. Application of fuzzy logic to approximate reasoning using linguistic synthesis // IЕЕЕ Transactions оn Computers. 1977. Vol. 26, № 12. Р. 1182—1191. 10. Zadeh L. А. Fuzzy sets // Information and Control. 1965. Vol. 8. P. 338—353. Kondratenko A., Bedrik A. military, ...

... convection-diffusion equation in the field of models of Rayleigh-Taylor instability in the equatorial region of Earth ionosphere is considered. For test tasks monotony of the constructed scheme is in number confirmed. Experimental value of an order of approximation of the offered method of nonlinear correction of the finitedifferential scheme is received. 1. Гайдуков В. Ю., Кащенко Н. М., Мациевский С. В. и др. Запуск экваториальных пузырей ...

... углеводородов : свидетельство о государственной регистрации базы данных № 2013620133, 09.01.2013. Alsynbaev K., Kozlov A. micro-seismic monitoring, a point cloud, faults, visual environment, approximation, a least square method, a convex shell, recognition algorithms 127-134

Often while seismic data processing one gets time dependent images (time cuts, time migration), in which time plays the role of the «depth» variable. If in some approximation the wave propagation velocity is known, these images can be transformed into the true ones. In this article for this purpose it is proposed to use semi-geodesic transform associated with the normal to the boundary rays. The results of simulations ...

... A model of heat transfer in a newborn cadaver presented as a finite cylinder is examined in detail. An important factor in constructing a mathematical model of postmortem heat transfer in a newborn aimed at identifying the time of death is body form approximation. It is shown that heat transfer in a cadaver is not sufficient for identifying the time of death, which should be based on a comprehensive assessment of postmortem changes. 1. Вавилов А. Ю. Судебно-медицинская ...

... на аппроксимациях Паде // Математическое моделирование. 2006. Т. 1, № 4. С. 89—99. 6. Stoer J., Bulirsch R. Introduction to numerical analysis. N. Y., 1992. 7. Baker G. A. P. Graves-Morris Pad'e Approximants. L., 1981 Buzdin A., Vasilyeva E. large system of linear equations, block decomposition, block-tridiagonal matrix, frequency-filtering method 161-169

... океанологических исследований» (МСОИ-2013). М., 2013. Т. 2. С. 181—184. 6. Smith W. H. F., Wessel P. Gridding with continuous curvature splines in tension// Geophysics. 1990. Vol. 55, No. 3. P. 293—305. Mysherin A. fishery oceanology, approximation of functions, interpolation, remote sensing data, Gridding algorithm 169-173

This article presents a method for approximate calculation of the compo-nents of an electromagnetic field produced by a cable system. This approach contributes to an efficient solution to the problem of electromagnetic compati-bility of radioelectronic equipment in a wide range of cable ...

... article considers the issues of trust in banks in terms of the rationality of clients’ behavior and behavioural economy. The author’s empirical study of 370 owners of small and microfirms located in the Warmian-Masurian voivodeship suggests that approximately 69 % of the respondents prefer the services of Polish banks (or those dominated by Polish capital) and 10.1 % prefer banks with foreign capital. The rest of the respondents (20.9 %) have no particular opinion on the subject. 1. Akerlof ...

The step-strip anodic dissolution technique was used to obtain concentration profiles of cathodic evolved H2 across the depth of Cr-Ni1810 steel under corrosion in water-salt media in the presence of SRB. The proposed approximation of the experimentally obtained distribution of hydrogen along the depth of steel by means of standard Gaussian function made it possible to establish the integral hydrogen content of the sub-layer (up to 80 μm) with high degree of accuracy....

... water body primary production. A numerical assessment of the filtration rate of these molluscs shows that they can filter daily an average of 2.41 ± 1.01 m3 of water per a square meter of the river bed. During the vegetation season, molluscs can clear approximately 380 m3 of water in estuaries removing up to 558.9 ± 65.7 g of suspended organic matters. 1. Алимов А. Ф. Некоторые общие закономерности процесса фильтрации у двустворчатых ...

... which allows us to identify the contribution of certain types of waves in the observed wave field. This work presents a procedure for constructing the projection operators for the Poincare and Rossby planetary waves in the spherical atmosphere in the approximation of "shallow water". The proposed procedure allows to obtain the generalized form of the projection operator approach without the use of β-plane. 1. Педлоски Дж. Геофизическая гидродинамика....

... Ранцман Е. Я. Морфоструктурные узлы — места активизации природных процессов // Вестник РАН. Сер. География. 1991. № 1. C. 5—9. 6. Gordon R. G. The plate tectonic approximation: Plate nonrigidity, diffuse plate boundaries, and global plate motions // Ann. Revs. Earth Plannet. Sci. 1998. Vol. 26.P.615—642. 7. Press F., Siever R. Understanding Earth. N. Y., 2000. 8. Vidyakina S. V., Averina N. G., Rassadina V....

Mathematical model of interaction between low density thermal plasma with charged simple shape space probe was considered. Molecular dynamics simulation method was used. Modeling result shows a positive cloud of protons before the satellite and ion shadow behind it. 1. Гальпеpин Ю. И., Гpигоpьев С. А., Зинин Л. В. и др. Расчеты распределения электрического потенциала вокруг спутника «Авpоpальный зонд» проекта Интербол // Препринт Институт космических исследований РАH. Пp-1879. 1993 ...

A variant of multigrid method for solving large systems of linear equations with block tridiagonal matrices that have higher robustness properties is presented.In this method the construction of coarse grid correction operators is based on approximation of the Schur complement. Numerical experiments show high efficiency of presented methods. 1.   Ольшанский М. А. Лекции и упражнения по многосеточным методам. М ., 2005. 2.  Hackbusch W ...

... of intramolecular tautomeric transformation is offered, accounts for the vibration of a proton as a result of its interaction with the surrounding medium simulated by the quantized field of radiation. Effective adiabatic potentials of the proton are approximated by the parabolas of various curvatures. The estimation for the vibrational relaxation time and the formula for the constant of tautomeric equilibrium. 1.  Грибов Л. А., Дементьев В. А., Завалий М. В. и др....

A multivalue method for decision of differential equations including fractional derivatives is offered. A research of approximation and stability of the method is carried out. 1.  Чукбар К. В. Стохастический перенос и дробные производные // Журн. эксперим. и теор. физики. 1995. Т. 108, вып....

... опыт их применения // УФН. 2000. 170. С . 565—568. 6. http :// geo - radar . ru 7. Polat B ., Meincke P . A forward model for ground penetrating radar imaging of buried pefect electric conductors within the physical optics approximation, Int. J. Electron. Commun. 2004. 58. P. 362—366. 8 . Jackson J. D. , Classical Electrodynamics, 3rd ed. Wiley , 1999. Yalunin S. V., Bessarab F. S., Karpov I. V., Radievsky A. V. ground penetrating radar, scattering problem. ...

The articles analyses orientation properties оn a vertical flat model of bulk layer from isosceles triangles. The authors present the distribution by angles, the height of the layer, and horizontal position and approximate empiric formula for probability density distribution by angles. 1. Займан Дж. Теоретическая физика однородно неупорядоченных систем. М., 1982. 2 . Клеман М., Лаврентович ...

... antenna is obtained. The equation of balance of power in the waveguide is evolved. The loss of the wave power from the waveguide through the slit is taken into account. To calculate the damping factor, the equation is obtained. The possibility of an approximate simplification of this equation is investigated. 1. Воскресенский Д.   И., Гостюхин В.   Л., Максимов В.   М. и др. Антенны и устрой­ства СВЧ / под ред. Д.   И. Воскресенского....

Difference methods an approximate solution of a three-dimensional equation of ions diffusion with mixed derivatives and divergence first derivatives are considered. The task is reduced to a chain of three two-dimensional parabolic equations on base of the summary approximation ...

... overview of Russian philosophers’ publications in German periodicals of the late 19th/early 20th centuries. At the time, Germany boasted a significant number of journals dedicated to philosophy or addressing philosophical problems. Even in the first approximation, there are several dozen journals featuring either texts by Russian scientists or works dedicated to Russian philosophy. Of special importance are two journals with the most pronounced presence of Russian authors, namely, Kant-Studien and ...

... increased tenfold since 2000 to reach over $14 billion by the end of 2012. According to the Central Bank of Belarus, Finnish firms have invested nearly $100 million in Belarus making Finland the sixteenth most active foreign investor in the country. Approximately 7,000 companies with foreign capital were registered in Belarus by the beginning of 2013. Finnish companies founded three dozen of these foreign firms. A lack of scientific reports on the perception of foreign businesspeople in the Belarusian ...

... identified in the case of the two regions — the Kaliningrad and Grodno: organisational and analytical support, methodological and technological support, and the development of a complex cooperation programme. The working version of the model includes approximately 150 events. As to its purpose, it is a representation of a well-balanced established international coordination programme of transboundary cooperation at a level of two regions. 1. Bilchak, V. S. 2001, Prigranichnaja jekonomika [Frontier ...

... websites. The authors identify the principle areas and leading centres of such cooperation. The NWFD universities have significant experience in cooperation with Finnish universities. Cooperation with Swedish universities is proved to be less developed. Approximately 50 NFWD universities, 29 of which are located in Saint Petersburg, are involved in cooperation; most NWFD universities do not cooperate with the mentioned countries. Such low degree of cooperation in the field of education is a serious inhibiting ...

... non-contractual obligations (Rome II), 2007, OJ L, no 199, p. 40. 17. European Parliament Resolution of 26 May 1989, 1989, OJ, p. 158/400. 18. European Parliament Resolution of 6 May 1994,1994, OJ, p. 205/518. 19. European Parliament Resolution on the approximation of the civil and commercial law of the Member States, 2001, COM, no 398. 20. Green Paper on Conflicts of Laws in Matters Concerning Matrimonial Property Regimes, Including the Question of Jurisdiction and Mutual recognition of 17 July 2006,...