On the extensions of uniformly continuous mappings
Nguyen To Nhu (1979)
Colloquium Mathematicae
Ofelia Alas, Lucia Junqueira, Jan Mill, Vladimir Tkachuk, Richard Wilson (2011)
Open Mathematics
For a topological property P, we say that a space X is star Pif for every open cover Uof the space X there exists Y ⊂ X such that St(Y,U) = X and Y has P. We consider star countable and star Lindelöf spaces establishing, among other things, that there exists first countable pseudocompact spaces which are not star Lindelöf. We also describe some classes of spaces in which star countability is equivalent to countable extent and show that a star countable space with a dense σ-compact subspace can have...
Jack G. Ceder (1992)
Mathematica Bohemica
Let and be closed subsets of [0,1] with a subset of the limit points of . Necessary and sufficient conditions are found for the existence of a continuous function such that is an -limit set for and is the set of fixed points of in .
Galvin, Fred (1981)
Abstracta. 9th Winter School on Abstract Analysis
M. Ghadermazi, O. A. S. Karamzadeh, M. Namdari (2013)
Rendiconti del Seminario Matematico della Università di Padova
Taras Radul (1998)
Commentationes Mathematicae Universitatis Carolinae
We introduce a functor of order-preserving functionals which contains some known functors as subfunctors. It is shown that this functor is weakly normal and generates a monad.
Stanisław Spież (1983)
Fundamenta Mathematicae
Marek Balcerzak (1986)
Mathematica Slovaca
Gabor, Grzegorz (2003)
Zeszyty Naukowe Uniwersytetu Jagiellońskiego. Universitatis Iagellonicae Acta Mathematica
R. Ayala, E. Dominguez, A. Márquez (1995)
Mathematica Scandinavica
Piotr Bartłomiejczyk, Piotr Nowak-Przygodzki (2014)
Open Mathematics
We prove that for n > 1 the space of proper maps P 0(n, k) and the space of local maps F 0(n, k) are not homotopy equivalent.
J. Krasinkiewicz (1974)
Fundamenta Mathematicae
Tomasz Natkaniec, Piotr Szuca (2016)
Fundamenta Mathematicae
For any Borel ideal ℐ we describe the ℐ-Baire system generated by the family of quasi-continuous real-valued functions. We characterize the Borel ideals ℐ for which the ideal and ordinary Baire systems coincide.
Aleksander Maliszewski (1998)
Fundamenta Mathematicae
The main goal of this paper is to characterize the family of all functions f which satisfy the following condition: whenever g is a Darboux function and f < g on ℝ there is a Darboux function h such that f < h < g on ℝ.
Yampolsky, Alexander L. Yampolsky, Alexander L. (2002)
Commentationes Mathematicae Universitatis Carolinae
We study the geometrical properties of a unit vector field on a Riemannian 2-manifold, considering the field as a local imbedding of the manifold into its tangent sphere bundle with the Sasaki metric. For the case of constant curvature , we give a description of the totally geodesic unit vector fields for and and prove a non-existence result for . We also found a family of vector fields on the hyperbolic 2-plane of curvature which generate foliations on with leaves of constant intrinsic...
Çiçek, Mustafa (1997)
International Journal of Mathematics and Mathematical Sciences
Robert Skiba (2001)
Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica
Jan Baars, Joost de Groot (1991)
Fundamenta Mathematicae
Oleg Okunev (2009)
Commentationes Mathematicae Universitatis Carolinae
We study relations between the Lindelöf property in the spaces of continuous functions with the topology of pointwise convergence over a Tychonoff space and over its subspaces. We prove, in particular, the following: a) if is Lindelöf, , and the point has countable character in , then is Lindelöf; b) if is a cozero subspace of a Tychonoff space , then and .
Ennio De Giorgi, Giuseppe Buttazzo, Gianni Dal Maso (1983)
Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni
Si dimostra che il funzionale è semicontinuo inferiormente su , rispetto alla topologia indotta da , qualora l’integrando sia una funzione non-negativa, misurabile in , convessa in , limitata nell’intorno dei punti del tipo , e tale che la funzione sia semicontinua inferiormente su .