Results 1 to 10 of about 55 (55)
Improving KKM Theory on General Metric Type Spaces
Topological Algebra and its Applications, 2021 A generalized metric type space is a generic name for various spaces similar to hyperconvex metric spaces or extensions of them. The purpose of this article is to introduce some KKM theoretic works on generalized metric type spaces and to show that they ...
Park Sehie
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On the Borel Classes of Set-Valued Maps of Two Variables
Annales Mathematicae Silesianae, 2020 Using the Borel classification of set-valued maps, we present here some new results on set-valued maps which are similar to some of the well known theorems on functions due to Lebesgue and Kuratowski.
Holá Ľubica, Kwiecińska Grażyna
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Borsuk’s antipodal fixed points theorems for compact or condensing set-valued maps
Advances in Nonlinear Analysis, 2018 We give a generalized version of the well-known Borsuk’s antipodal fixed point theorem for a large class of antipodally approachable condensing or compact set-valued maps defined on closed subsets of locally convex topological vector spaces.
Altwaijry Najla +3 more
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An Ulam stability result on quasi-b-metric-like spaces
Open Mathematics, 2016 In this paper a class of general type α-admissible contraction mappings on quasi-b-metric-like spaces are defined. Existence and uniqueness of fixed points for this class of mappings is discussed and the results are applied to Ulam stability problems ...
Alsulami Hamed H. +3 more
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Periodic solutions for nonautonomous differential equations and inclusions in tubes
Abstract and Applied Analysis, Volume 2004, Issue 12, Page 1057-1079, 2004., 2004 We study the existence of periodic trajectories for nonautonomous differential equations and inclusions remaining in a prescribed compact subset of an extended phase space. These sets of constraints are nonconvex right‐continuous tubes not satisfying the viability tangential condition on the whole boundary.
Grzegorz Gabor
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On common fixed points, periodic points, and recurrent points of continuous functions
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 39, Page 2465-2473, 2003., 2003 It is known that two commuting continuous functions on an interval need not have a common fixed point. However, it is not known if such two functions have a common periodic point. we had conjectured that two commuting continuous functions on an interval will typically have disjoint sets of periodic points.
Aliasghar Alikhani-Koopaei
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A convex-valued selection theorem with a non-separable Banach space
Advances in Nonlinear Analysis, 2018 In the spirit of Michael’s selection theorem [6, Theorem 3.1”’], we consider a nonempty convex-valued lower semicontinuous correspondence φ:X→2Y{\varphi:X\to 2^{Y}}.
Gourdel Pascal, Mâagli Nadia
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KKM theorem with applications to lower and upper bounds equilibrium problem in G‐convex spaces
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 51, Page 3267-3276, 2003., 2003 We give some new versions of KKM theorem for generalized convex spaces. As an application, we answer a question posed by Isac et al. (1999) for the lower and upper bounds equilibrium problem.
M. Fakhar, J. Zafarani
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On S‐cluster sets and S‐closed spaces
International Journal of Mathematics and Mathematical Sciences, Volume 23, Issue 9, Page 597-603, 2000., 2000 A new type of cluster sets, called S‐cluster sets, of functions and multifunctions between topological spaces is introduced, thereby providing a new technique for studying S‐closed spaces. The deliberation includes an explicit expression of S‐cluster set of a function.
M. N. Mukherjee, Atasi Debray
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Semilocal connectedness of product spaces and s‐continuity of maps
International Journal of Mathematics and Mathematical Sciences, Volume 24, Issue 4, Page 257-264, 2000., 2000 We consider the problem of the transfer of semilocal connectedness from factors to the product space and vice versa. Some sufficient conditions are given under which the product of semilocally connected spaces is semilocally connected. Obtained theorems are not invertible, suitable examples are given.
Janina Ewert
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