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МатеріалAlmost geodesic mappings of affinely connected spaces that preserve the Riemannian curvature(Líceum University Press, 2015) Березовський, Володимир Євгенійович ; Berezovskii, V. E.In the present paper the authors give some conditions preserved Riemannian curvature tensor with respect to almost geodesic mappings of affinely connected spaces. It is noteworthy that these conditions are valid for other types of mappings. For the almost geodesic mappings of first type, when the Riemannian curvature tensor is invariant, the authors deduce a differential equations system of Cauchy type. In addition the authors investigate almost geodesic mappings of first type, where the Weyl tensor of projective curvature is invariant and Riemannian tensor is not invariant.
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МатеріалAlmost geodesic mappings of first type on spaces with affine connection onto symmetric spaces(Kharkiv Mathematical Society, 2016) Березовський, Володимир Євгенійович ; Berezovsky, V.E.
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МатеріалAlmost geodesic mappings of spaces with affine connection(Springer US, 2015) Березовський, Володимир Євгенійович ; Berezovskii, V. E.This paper is devoted to the further development of the theory of almost geodesic mappings of spaces with affine connection.
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МатеріалAlmost geodesic mappings of the fist type onto symmetric spaces(Slovak University of Technology in Bratislava, 2017) Березовський, Володимир ЄвгенійовичThe artscle is devoted to the theory of almost geodesic mappings of the first type onto symmetric spaces. There are found certain necessary and sufficient conditions when a space with affine connection admits a canonical almost geodesic mappings of the first type onto symmetric spaces.
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МатеріалAlmost geodesic mappings of the second type of spaces with affine connection onto two-symmetric spaces(Spektrum STU, 2019) Березовський, Володимир Євгенійович ; Лещенко, Світлана Валентинівна ; Ненька, Руслана ВолодимирівнаIn the paper we consider canonical almost geodesic mappings of type _2(e) of spaces with affine connection onto two-symmetric spaces. The main equations for the mappings are obtained as a closed mixed system of PDEs of Cauchy type. We have found the maximum number of essential parameters which the solution of the system depends on.
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МатеріалALMOST GEODESIC MAPPINGS OF TYPE pi1 OF SPACES WITH AFFINE CONNECTION(Society of mathematicians and physicists of Montenegro and Department of Mathematics of The University of Montenegro, 2021) Березовський, Володимир ЄвгенійовичWe consider almost geodesic mappings of spaces with affine connections. This mappings are a special case of firsttype almost geodesic mappings. We have found the objects which are invariants of the mappings pi1. The fundamental equations of these mappings are in Cauchy form. We study mappings of constant curvature spaces.
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МатеріалAlmost geodesic mappings onto generalized Ricci-symmetric manifolds(College of Nyíregyháza, 2010) Березовський, Володимир Євгенійович ; Berezovskii, V. E.Our aim is to continue investigations concerning existence of almost geodesic mappings of manifolds with linear connection. We deduce necessary and sufficient conditions for existence of the so-called canonical almost geodesic mappings of type π of a manifold endowed with a linear connection onto generalized Ricci-symmetric manifolds. Our result is a generalization of some previous results by N. S. Sinyukov.
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МатеріалAnalysis of innovative development of Ukrainian enterprises in the context of European innovative development(VUZF University, 2020) Бурляй, Аліна Павлівна ; Бурляй, Олександр Леонідович ; Ковальов, Леонід ЄвгенійовичThis article is devoted to the study of the level of innovative development of Ukraine in comparison with the level of innovative development of European countries. The main problems of innovative development of the country are considered and the factors influencing this process are analyzed. The essence of the concept of “innovation” is studied and the characteristic features inherent in them are highlighted. The own definition of innovative development of enterprises is formulated. The weaknesses and strengths of Ukraineʼs innovation development were assessed in terms of the parameters of the global innovation index using SWOT-analysis.
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МатеріалApproximation of the Dependence of the Radius of the Atomic Nucleus on Its Parameters Using a Fuzzy Hybrid Network Model(Springer, 2018) Ковальов, Леонід ЄвгенійовичIn the present investigation, the model of the hybrid network in the form of an adaptive system neuro-fuzzy inference is developed for approximating the dependence of the radius of an atomic nucleus vs. its charge and mass number. With the use of developed model, the radii of 84 nuclides for which experimental data on their sizes were not available were estimated.
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МатеріалCanonical almost geodesic mappings of the first type of spaces with affine connection onto generalized 2-Ricci-symmetric spaces(Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 2021) Березовський, Володимир Євгенійович ; Лещенко, Світлана ВалентинівнаIn the paper we consider almost geodesic mappings of the first type of spaces with affine connections onto generalized 2-Ricci-symmetric spaces. The main equations for the mappings are obtained as a closed system of linear differential equations of Cauchy type in the covariant derivatives. The obtained result extends an amount of research produced by Sinyukov, Berezovski and Mikeš.
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МатеріалCanonical Almost Geodesic Mappings of the First Type of Spaces with Affine Connections onto Generalized m-Ricci-Symmetric Spaces(MDPI, 2021) Березовський, Володимир ЄвгенійовичIn the paper we consider almost geodesic mappings of the first type of spaces with affine connections onto generalized 2-Ricci-symmetric spaces, generalized 3-Ricci-symmetric spaces, and generalized m-Ricci-symmetric spaces. In either case the main equations for the mappings are obtained as a closed system of linear differential equations of Cauchy type in the covariant derivatives. The obtained results extend an amount of research produced by N.S. Sinyukov, V.E. Berezovski, J. Mikeš.
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МатеріалCanonical Almost Geodesic Mappings of the First Type onto Generalized Ricci Symmetric Spaces(University of Nis, Serbia, 2022) Березовський, Володимир ЄвгенійовичIn the paper we consider canonical almost geodesic mappings of spaces with affine connection onto m-Ricci-symmetric spaces. In particular, we studied in detail canonical almost geodesic mappings of the first type of spaces with affine connections onto 2- and 3-Ricci-symmetric spaces. In either case the main equations for the mappings have been obtained as a closed mixed system of PDEs of Cauchy type. We have found the maximum number of essential parameters which the solution of the system depends on.
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МатеріалCanonical almost geodesic mappings of type π1 onto pseudo-Riemannian manifolds(Hackensack, NJ: World Scientific, 2008) Березовський, Володимир Євгенійович ; Berezovskii, V. E.In this paper, the authors study properties of canonical almost geodesic mappings of type π˜1 onto pseudo-Riemannian manifolds. They find necessary and sufficient conditions for existence of the canonical almost geodesic mappings of type π˜1 of a manifold endowed with a linear connection onto pseudo-Riemannian manifolds. The conditions are described by means of a closed system of partial differential equations of first order of Cauchy type.
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МатеріалCanonical F-Planar Mappings of Spaces with Affine Connection onto m-Symmetric Spaces(MDPI, 2023) Березовський, Володимир ЄвгенійовичIn this paper, we consider canonical F-planar mappings of spaces with affine connection onto m-symmetric spaces. We obtained the fundamental equations of these mappings in the form of a closed system of Chauchy-type equations in covariant derivatives. Furthermore, we established the number of essential parameters on which its general solution depends.
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МатеріалComplex Submanifolds of LCK-manifold, Pseudo-Vaisman and Vaisman Manifolds(Slovak University of Technology in Bratislava, 2017) Березовський, Володимир ЄвгенійовичStudy the immersions of submanifolds in LCK-manifolds that a tangent space in all points of the submanifolds to be normal to Lee field and we find conditions under which LCK-manifold admits the immersion of complex submanifolds. Also we explore properties of Lee form of Vaisman and pseudo-Vaisman manifold.
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МатеріалCONFORMAL AND GEODESIC MAPPINGS ONTO RICCI SYMMETRIC SPACES(Institute of Mathematics and Physics, SjF STU in Bratislava, 2020) Березовський, Володимир ЄвгенійовичIn this paper, we consider the conformal and geodesic mappings onto Ricci symmetric spaces. We obtained fundamental equations in the Cauchy type form, which depend on finite real parameters.
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МатеріалConformal and Geodesic Mappings onto Some Special Spaces(MDPI AG, Basel, Switzerland, 2019) Березовський, Володимир ЄвгенійовичIn this paper, we consider conformal mappings of Riemannian spaces onto Ricci-2-symmetric Riemannian spaces and geodesic mappings of spaces with affine connections onto Ricci-2-symmetric spaces. The main equations for the mappings are obtained as a closed system of Cauchy-type differential equations in covariant derivatives. We find the number of essential parameters which the solution of the system depends on. A similar approach was applied for the case of conformal mappings of Riemannian spaces onto Ricci-m-symmetric Riemannian spaces, as well as geodesic mappings of spaces with affine connections onto Ricci-m-symmetric spaces.
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МатеріалConformal mappings of Riemannian manifolds preserving the generalized Einstein tensor(Slovak University of Technology in Bratislava, 2018) Березовський, Володимир ЄвгенійовичWe study conformal mappings preserving the generalized Einstein tensor. We have derived corresponding partial differential equations and their integrability conditions. In addition to the generalized Einstein tensor we got other invariants of the mappings. Also we have proved that orientable compact manifolds equipped by positive definite metric, do not admit conformal mappings preserving the generalized Einstein tensor.
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МатеріалConformal Mappings of Riemannian Spaces onto Ricci Symmetric Spaces(Pleiades Publishing, 2018) Березовський, Володимир ЄвгенійовичIn this paper consider conformal mappings of Riemannian spaces Vn onto Ricci symmetric Riemannian spaces. Note that Ricci symmetric spaces are characterized by the covariant constancy of the Ricci tensor; thereby, they are a natural generalization of Einstein spaces.
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МатеріалConharmonic Transformations of Locally Conformal Kahler Manifolds(Odessa National Academy of Food Technologies, 2021) Березовський, Володимир Євгенійович