429 research outputs found

    Development of Small and Medium-Sized Regional Enterprises: Creation of Priority Areas (the Case of Sverdlovsk Region)

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    This article presents the results of the research which deals with the current level of development of small and medium enterprises (SMEs) in Sverdlovsk region. The study analyses the statistics of entrepreneurship development as well as Russian and international experience in this sphere. It also includes a sociological survey of entrepreneurs’ satisfaction with the business climate in the region. The research was aimed at elaborating guidelines for the long-term development of a regional entrepreneurship support system. This system seeks to facilitate the implementation of the ‘Strategy for the Development of Small and Medium Enterprises in Sverdlovsk Region before 2030’. As a result, an amalgam of strategic responses for the development of SMEs is presented. The completed response comprises measures intended to address the problems entrepreneurs face by developing SME support tools; to solve the endemic problems of the sector by improving the system of regional SME support; and to promote the realization of concrete priority areas for entrepreneurship development.The research work was carried out in collaboration with the Ural Federal University n.a. the First President of Russia B. N. Yeltsin and OOO “Analytical Centre Expert-Ural’” at the request of Sverdlovsk Regional Entrepreneurship Support Fund. The research was conducted in the period of September-November 2014. The state programme of Sverdlovsk region ‘Development of Industry and Science in Sverdlovsk Region Before 2020’ (approved by the Order of Sverdlovsk government of 24 October 2013 № 1293-ПП)

    Modeling the burnout of solid polydisperse fuel under the conditions of external heat transfer

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    A self-similar burnout mode of solid polydisperse fuel is considered taking into consideration heat transfer between fuel particles, gases, and combustion chamber walls. A polydisperse composition of fuel is taken into account by introducing particle distribution functions by radiuses obtained for the kinetic and diffusion combustion modes. Equations for calculating the temperatures of particles and gases are presented, which are written for particles average with respect to their distribution functions by radiuses taking into account the fuel burnout ratio. The proposed equations take into consideration the influence of fuel composition, air excess factor, and gas recirculation ratio. Calculated graphs depicting the variation of particle and gas temperatures, and the fuel burnout ratio are presented for an anthracite-fired boiler. © 2013 Pleiades Publishing, Inc

    Formation and development of the processing industry in the AIC of the region

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    The theoretical grounding of the management system of animal feedingstuff milling of the region was performed. The facilities of animal feedingstuff milling are divided according to the degree of independence of business conducting and directions of sales of the products manufactured. The factors of the internal and external environment of the animal feedingstuff milling of the region were considered. The analysis was performed and the tendencies in the development of animal feedingstuff milling of the region and the system of its management were revealed; the directions of the development of animal feedingstuff milling of the agrarian region were grounded. The potential capacity of the regional market of animal feedingstuff for livestock breeding of the region was calculated. It was offered to form the body of economic management in the form of an independent legal entity bearing the responsibility for execution of the functions imposed on it to develop and implement the plan of development of animal feedingstuff milling – JSC Animal Feedingstuff Cluster of the Altai Territory.peer-reviewe

    МАГНИТНЫЕ СВОЙСТВА МНОГОКОМПОНЕНТНЫХ ГЕТЕРОГЕННЫХ СРЕД С ДВОЯКОПЕРИОДИЧЕСКОЙ СТРУКТУРОЙ

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    Heterogeneous media have a wide range of practical applications. Media with a doubly periodic structure (matrices of high-gradient magnetic separators, etc.) occupy an important place. Their study is usually based on experimental and approximate methods and is limited to simple two-phase systems. The development of universal and accurate methods of mathematical modelling of electrophysical processes in such environments is an urgent task. The aim of the paper is to develop a method for calculating local and effective parameters of a magnetostatic field with minimal restrictions on the number of phases, their geometry, concentration, and magnetic properties. Based on the theory of elliptic functions and secondary sources, an integral equation is formulated with respect to the magnetization vector of the elements of the main parallelogram of the periods. The calculated expressions for the complex potential, field strength, and components of the effective magnetic permeability tensor are obtained. The results of a series of computational experiments confirming the universality and effectiveness of the method are presented. As an example of a practical application, a detailed study of the field of the magnetic forces of the matrix is carried out: the lines of magnetic isodine and potential extraction areas for a complex version of the matrix are constructed. Within the framework of the developed method, the calculation of local and effective field characteristics is carried out by solving the field problem in the field of an arbitrary parallelogram of periods without specifying boundary conditions on its sides with a comprehensive consideration of significant interdependent factors. The practical value of the method is to create new opportunities for improving the technical characteristics of electrophysical devices for which the universality and accuracy of calculating local and effective field characteristics is decisive. An algorithm for optimizing the characteristics of the separator is proposed. Изложен метод расчета магнитостатического поля в двоякопериодической гетерогенной среде. Сформулировано интегральное уравнение относительно вектора намагниченности элементов среды. Расчет характеристик поля осуществляется путем решения полевой задачи в области основного параллелограмма периодов без задания граничных условий на его сторонах. Получены расчетные выражения для напряженности поля и тензора магнитной проницаемости. Приведены результаты вычислительных экспериментов, подтверждающих универсальность и эффективность метода. Проведено детальное исследование поля магнитных сил матрицы высокоградиентного магнитного сепаратора. Метод открывает новые возможности повышения технических характеристик электрофизических устройств, для которых универсальность и точность расчета локальных и эффективных характеристик поля является определяющей

    Cooper pair dispersion relation for weak to strong coupling

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    Cooper pairing in two dimensions is analyzed with a set of renormalized equations to determine its binding energy for any fermion number density and all coupling assuming a generic pairwise residual interfermion interaction. \ Also considered are Cooper pairs (CPs) with nonzero center-of-mass momentum (CMM)--usually neglected in BCS theory--and their binding energy is expanded analytically in powers of the CMM up to quadratic terms. A Fermi-sea-dependent {\it linear} term in the CMM dominates the pair excitation energy in weak coupling (also called the BCS regime) while the more familiar quadratic term prevails in strong coupling (the Bose regime). The crossover, though strictly unrelated to BCS theory {\it per se,} is studied numerically as it is expected to play a central role in a model of superconductivity as a Bose-Einstein condensation of CPs where the transition temperature vanishes for all dimensionality d2d\leq 2 for quadratic dispersion, but is {\it nonzero} for all d1d\geq 1 for linear dispersion.Comment: 11 pages plus 3 figures, revised version accepted in Physical Review

    Short-Wave Excitations in Non-Local Gross-Pitaevskii Model

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    It is shown, that a non-local form of the Gross-Pitaevskii equation allows to describe not only the long-wave excitations, but also the short-wave ones in the systems with Bose-condensate. At given parameter values, the excitation spectrum mimics the Landau spectrum of quasi-particle excitations in superfluid Helium with roton minimum. The excitation wavelength, at which the roton minimum exists, is close to the inter-particle interaction range. It is shown, that the existence domain of the spectrum with a roton minimum is reduced, if one accounts for an inter-particle attraction.Comment: 5 pages, 5 figures, UJP style; presented at Bogolyubov Kyiv Conference "Modern Problems of Theoretical and Mathematical Physics", September 15-18, 200

    Adiabatic approximation, Gell-Mann and Low theorem and degeneracies: A pedagogical example

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    We study a simple system described by a 2x2 Hamiltonian and the evolution of the quantum states under the influence of a perturbation. More precisely, when the initial Hamiltonian is not degenerate,we check analytically the validity of the adiabatic approximation and verify that, even if the evolution operator has no limit for adiabatic switchings, the Gell-Mann and Low formula allows to follow the evolution of eigenstates. In the degenerate case, for generic initial eigenstates, the adiabatic approximation (obtained by two different limiting procedures) is either useless or wrong, and the Gell-Mann and Low formula does not hold. We show how to select initial states in order to avoid such failures.Comment: 6 pages, 2 figure

    Bose-Einstein Condensation in the Relativistic Pion Gas: Thermodynamic Limit and Finite Size Effects

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    We consider the Bose-Einstein condensation (BEC) in a relativistic pion gas. The thermodynamic limit when the system volume VV goes to infinity as well as the role of finite size effects are studied. At VV\to \infty the scaled variance for particle number fluctuations, ω=/\omega=/, converges to finite values in the normal phase above the BEC temperature, T>TCT>T_C. It diverges as ωV1/3\omega \propto V^{1/3} at the BEC line T=TCT=T_C, and ωV\omega \propto V at T<TCT<T_C in a phase with the BE condensate. Possible experimental signals of the pion BEC in finite systems created in high energy proton-proton collisions are discussed
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