Now showing items 160-179 of 245

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      New examples of generalized Sasakian-space-forms  [Article]

      Carriazo Rubio, Alfonso; Alegre Rueda, Pablo Sebastián; Özgür, Cihan; Sular, Sibel (Università di Torino, 2015)
      In this paper we study when a non-anti-invariant slant submanifold of a generalized Sasakian-space-form inherits such a ...
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      New relationships involving the mean curvature of slant submanifolds in S-space-forms  [Article]

      Fernández Fernández, Luis Manuel; Hans Uber, María Belén (Korean Mathematical Society, 2007)
      Relationships between the Ricci curvature and the squared mean curvature and between the shape operator associated with ...
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      Normal approximations of regular curves and surfaces  [Article]

      Carriazo Rubio, Alfonso; Márquez García, María del Carmen; Ugail, Hassan (Faculty of Sciences and Mathematics, University of Nis, Serbia, 2015)
      Bezier curves and surfaces are two very useful tools in Geometric Modeling, with many applications. In this paper, we will ...
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      Null pseudo-isotropic Lagrangian surfaces  [Article]

      Carriazo Rubio, Alfonso; Martín Molina, Verónica; Vrancken, Luc (Polish Academy of Sciences, Institute of Mathematics, 2017)
      In this paper we will show that a Lagrangian, Lorentzian surface M 2 1 in a complex pseudo space form Mf2 1 (4c) is ...
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      Nullification and cellularization of classifying spaces of finite groups  [Article]

      Flores Díaz, Ramón Jesús (American Mathematical Society, 2007-04)
      In this note we discuss the effect of the BZ/p-nullification PBZ/p and the BZ/p-cellularization CWBZ/p over classifying ...
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      Nullification functors and the homotopy type of the classifying space for proper bundles  [Article]

      Flores Díaz, Ramón Jesús (Mathematical Sciences Publishers, 2005-09)
      Let G be a discrete group for which the classifying space for proper G-actions is finite-dimensional. We find a space W ...
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      Obtaining combinatorial structures associated with low-dimensional Leibniz algebras  [Presentation]

      Ceballos González, Manuel; Núñez Valdés, Juan; Tenorio Villalón, Ángel Francisco (2013)
      In this paper, we analyze the relation between Leibniz algebras and combinatorial structures. More concretely, we study ...
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      On abelian subalgebras and ideals of maximal dimension in supersolvable Lie algebras  [Article]

      Ceballos González, Manuel; Towers, David A. (Elsevier, 2014-02)
      In this paper, the main objective is to compare the abelian subalgebras and ideals of maximal dimension for finite-dimensional ...
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      On certain anti-invariant submanifolds of an S-manifold  [Article]

      Cabrerizo Jaraíz, José Luis; Fernández Fernández, Luis Manuel (Sociedade Portuguesa de Matemática, 1993)
      In this paper, the geometry of certain anti-invariant submanifolds of an S-manifold, namely those which are normal to the structure vector fields, is studied.
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      On generalized Sasakian-space-forms  [Presentation]

      Carriazo Rubio, Alfonso; Blair, David E.; Alegre Rueda, Pablo Sebastián (2004)
      We study contact metric and trans-Sasakian generalized Sasakian-space-forms. We also give some interesting examples of generalized Sasakian-space-forms by using warped products and conformal changes of metric.
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      On manifolds with nonhomogeneous factors  [Article]

      Cárdenas Escudero, Manuel Enrique; Fernández Lasheras, Francisco Jesús; Quintero Toscano, Antonio Rafael; Repovš, Dušan (Springer, 2012-06)
      We present simple examples of finite-dimensional connected homogeneous spaces (they are actually topological manifolds) ...
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      On pseudo-Einstein hypersurfaces of ℋ2n+s  [Article]

      Cabrerizo Jaraíz, José Luis; Fernández Fernández, Luis Manuel; Fernández Andrés, Manuel (Indian National Science Academy, 1996-05)
      In this paper, some properties of the geometry of pseudo-Einstein hypersurfaces of the S-manifold ℋ 2n+s are studied and a theorem concerning their principal curvatures is obtained.
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      On slant submanifolds of neutral Kaehler manifolds  [Article]

      Arslan, Kadri; Carriazo Rubio, Alfonso; Chen, Bang-Yen; Murathan, Cengizhan (Mathematical Society of the Republic of China, 2010-04)
      An indefinite Riemannian manifold is called neutral it its index is equal to one half of its dimension and an indefinite ...
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      On surfaces in digital topology  [Presentation]

      Ayala Gómez, Rafael; Domínguez Murillo, Eladio; Francés Román, Ángel Ramón; Quintero Toscano, Antonio Rafael; Rubio Sender, Julio (1995)
      In R. Ayala, E. Domínguez, A.R. Francés, A. Quintero, J. Rubio. A Polyhedral Approach to Digital Topology a new framework ...
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      On the classifying space for proper actions of groups with cyclic torsion  [Article]

      Antolín Pichel, Yago; Flores Díaz, Ramón Jesús (De Gruyter, 2014-01)
      In this paper we introduce a common framework for describing the topological part of the Baum-Connes conjecture for a ...
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      On the connectivity of skeletons of pseudomanifolds with boundary  [Article]

      Ayala Gómez, Rafael; Chávez de Diego, María José; Márquez Pérez, Alberto; Quintero Toscano, Antonio Rafael (Mathematical Institute, Academy of Sciences of the Czech Republic, 2002)
      In this note we show that 1-skeletons and 2-skeletons of n-pseudomanifolds with full boundary are (n+ 1)-connected graphs and n-connected 2-complexes, respectively. This generalizes previous results due to Barnette and Woon.
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      On the existence of almost contact structure and the contact magnetic field  [Article]

      Cabrerizo Jaraíz, José Luis; Fernández Andrés, Manuel; Gómez Casanueva, Juan Salvador (Springer, 2009-10)
      In this short note we give a simple proof of the existence of an almost contact metric structure on any orientable ...
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      On the Freudenthal extensions of proper confluent maps  [Article]

      Charatonik, Wlodzimierz J; Fernández Bayort, Tomás; Quintero Toscano, Antonio Rafael (University of Houston, 2012)
      In this paper we study when Freudenthal extensions of proper maps preserve the (weak, semi) confluency. Also the extensions to the Alexandroff one-point compactificaton are considered.
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      On the idempotency of some composite functors  [Article]

      Flores Díaz, Ramón Jesús (Springer, 2012-01)
      We present examples of localization functors whose composition with certain cellularization functors is not idempotent, and vice versa.
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      On the locally finite chain algebra of a proper homotopy type  [Article]

      Baues, Hans Joachim; Quintero Toscano, Antonio Rafael (Belgian Mathematical Society, 1996)
      In the classical paper [A-H] Adams-Hilton constructed a free chain algebra which is an important algebraic model of a ...