Now showing items 1-20 of 238

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      Bi-slant submanifolds of para Hermitian manifolds  [Article]

      Alegre Rueda, Pablo Sebastián; Carriazo Rubio, Alfonso (MDPI, 2019-07-11)
      In this paper, we introduce the notion of bi-slant submanifolds of a para Hermitian manifold. They naturally englobe CR, semi-slant, and hemi-slant submanifolds. We study their first properties and present a whole gallery ...
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      The curvature tensor of almost cosymplectic and almost Kenmotsu (κ,μ,ν)-spaces  [Presentation]

      Carriazo Rubio, Alfonso; Martín Molina, Verónica (2013)
      We study the Riemann curvature tensor of (κ,μ, ν)-spaces when they have almost cosymplectic and almost Kenmotsu structures, giving its writing explicitly. This leads to the definition and study of a natural generalisation ...
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      Invariant functions and contractions of algebras.  [PhD Thesis]

      Escobar Rica, Jose María (2019-04-08)
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      The curvature tensor of almost cosymplectic and almost Kenmotsu ( κ, μ, ν ) -space  [Article]

      Carriazo Rubio, Alfonso; Martín Molina, Verónica (Springer, 2013-08)
      We study the Riemann curvature tensor of (κ, µ, ν)-spaces when they have almost cosymplectic and almost Kenmotsu structures, giving its writing explicitly. This leads to the definition and study of a natural generalisation of ...
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      Un ejemplo de teoría de bordismo equivalente al PL-bordismo  [Article]

      Quintero Toscano, Antonio Rafael (Academia de Ciencias Exactas, Físicas, Químicas y Naturales de Zaragoza, 1983)
      In this paper we define the CPL-manifolds and we prove, by using a desingularization procedure, that these objects give a bordism theory which is equivalente to the PL-bordism. It's interesting to note that the famíly CPL ...
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      Cellular covers of local groups  [Article]

      Flores Díaz, Ramón Jesús; Scherer, Jérôme (Springer, 2018-12)
      We prove that, in the category of groups, the composition of a cellularization and a localization functor need not be idempotent. This provides a negative answer to a question of Emmanuel Dror Farjoun.
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      La forma de Maslov de las subvariedades Slant.  [PhD Thesis]

      Barrera López, Joaquín (2018-11-30)
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      Some special types of developable ruled surface  [Article]

      Alegre Rueda, Pablo Sebastián; Arslan, Kadri; Carriazo Rubio, Alfonso; Murathan, Cengizhan; Özturk, Günay (Hacettepe University (Faculty of Science), 2010)
      In this study we consider the focal curve Cγ of a space curve γ and its focal curvatures. We characterize some special types of ruled surface, choosing one of the base curves or director curves as the focal curve of the ...
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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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      CR-products of S-manifolds  [Article]

      Fernández Fernández, Luis Manuel (Sociedade Portuguesa de Matemática, 1990)
      In this paper certain CR-submanifolds namely the CR-products, are studied. A characterization theorem is given and the case of CR-products of S-manifolds whose invariant f-sectional curvature is constant, is investigated.
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      Irreducible triangulations of the once-punctured torus  [Article]

      Lawrecenko, Serge; Sulanke, Thom; Villar Liñán, María Trinidad; Zgonnik, Lyudmila Vladimirovna; Chávez de Diego, María José (Sobolev Institute of Mathematics, 2018)
      A triangulation of a surface with fixed topological type is called irreducible if no edge can be contracted to a vertex while remaining in the category of simplicial complexes and preserving the topology of the surface. A ...
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      A historical perspective of the theory of isotopisms  [Article]

      Falcón Ganfornina, Raúl Manuel; Falcón Ganfornina, Óscar Jesús; Núñez Valdés, Juan (MDPI, 2018-08-03)
      In the middle of the twentieth century, Albert and Bruck introduced the theory of isotopisms of non-associative algebras and quasigroups as a generalization of the classical theory of isomorphisms in order to study and ...
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      A classification of totally geodesic and totally umbilical Legendrian submanifolds of (κ, μ)-spaces  [Article]

      Carriazo Rubio, Alfonso; Martín Molina, Verónica; Vrancken, Luc (Springer, 2018)
      We present classifications of totally geodesic and totally umbilical Legendrian submanifolds of (κ, µ)-spaces with Boeckx invariant I ≤ −1. In particular, we prove that such submanifolds must be, up to local isometries, ...
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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 offer a new method to provide approximations of regular curves and surfaces by Bezier ones, with ...
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      Pyramidal values  [Article]

      Flores Díaz, Ramón Jesús; Molina Ferragut, Elisenda; Tejada Cazorla, Juan Antonio (Springer, 2014-06)
      We propose and analyze a new type of values for cooperative TU-games, which we call pyramidal values. Assuming that the grand coalition is sequentially formed, and all orderings are equally likely, we define a pyramidal ...
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      The cellular structure of the classifying spaces of finite groups  [Article]

      Flores Díaz, Ramón Jesús; Foote, Richard M. (Springer, 2011-08)
      In this paper we obtain a description of the BZ/p-cellularization (in the sense of Dror-Farjoun) of the classifying spaces of all finite groups, for all primes p.
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      El papel de las webquest en las NTIC  [Presentation]

      Falcón Ganfornina, Óscar Jesús; Falcón Ganfornina, Raúl Manuel; Núñez Valdés, Juan; Tenorio Villalón, Ángel Francisco (2008-07)
      La ponencia que aquí se presenta persigue un triple objetivo. Por una parte, mostrarle al lector en general, y al profesorado de Secundaria y Bachillerato en particular, el concepto de WebQuest (WQ) y sus principales ...
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      Basic concepts on Lorentz simmetry and Minkowsky isogeometry by using the MCIM isotopic model  [Presentation]

      Falcón Ganfornina, Raúl Manuel; Núñez Valdés, Juan (2004-09)
      At 1978, R.M. Santilli proposed to generalize the conventional Lie theory by using isotopies. To do it, he considered that the basic unit of any mathematical structure can depend on external factors (such as positions, ...
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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 structure, on the assumption that it is totally geodesic, totally umbilical, totally contact geodesic ...
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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 pseudo-isotropic if and only if M is minimal. Next we will obtain a complete classification of all ...