Sample records for GEOMETRIA DIFERENCIAL (differential geometry)
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1

Corchete y curvatura

Di Scala, Antonio J.
2005-12-01

Resumen en español La primera parte del artículo presenta al corchete de Lie asociado al problema de la comutatividad de dos flujos. En la segunda parte se introducen las definiciones básicas de conexión y curvatura en fibrados vectoriales, subrayando la relación corchete-curvatura. Finalmente, usando conexiones afines localmente definidas, se da una demostración original y sencilla de un teorema de Eugenio Beltrami. Este artículo apunta a un lector no especialista (e.g. un estudiante de doctorado en matemática o física, etc) en geometría diferencial local. Resumen en inglés The first part of this article presents the definition of Lie Bracket related to commuting flows of vector fields. In the second part, basic definitions and of connections and curvature are given in order to emphasize the link between Lie Brackets and curvature. Finally, by using locally-defined connections, we give a short and original proof of a classical theorem of Beltrami. The article is addressed to a non specialist in local differential geometry.

Scientific Electronic Library Online (Spanish)

2

Detección y localización de fallas mediante el uso de observadores no lineales para procesos de copolimerización en emulsión/ Fault detection and isolation using nonlinear observers for emulsion copolimerization processes

Téllez Anguiano, Adriana del Carmen; Astorga Zaragoza, Carlos Manuel; Reyes Reyes, Juan; Álvarez Castillo, Alberto; Medina, Manuel Adam
2009-09-01

Resumen en español En este trabajo se presenta el diseño e implementación de un sistema de detección y localización de fallas para un proceso de copolimerización en emulsión. El enfoque propuesto para el diseño de los generadores de residuos está basado en técnicas de desacoplo usando geometría diferencial y el uso de observadores no lineales de alta ganancia, en el cual cada uno de los residuos se encuentra dedicado a la detección y a la localización de una falla en particular. (mas) Las fallas consideradas en este trabajo son de tipo aditivo, presentes en los actuadores del proceso, que representan un mal funcionamiento de las bombas de alimentación de flujo de monómeros hacia el interior del reactor. Una de las principales ventajas del método propuesto son los observadores utilizados como generadores de residuos, los cuales son fáciles de implementar y de sencilla calibración, lo que favorece su aplicación en línea. La eficacia del método se valida en simulación para el caso de un proceso de copolimerización en emulsión entre el acrilato de butilo y el estireno. Resumen en inglés In this work the design and implementation of a fault detection and isolation system for a process of copolymerization in emulsion are presented. The proposed approach used to design the residual generators is based on decoupling techniques using differential geometry and high gain nonlinear observers; every residue is dedicated to the detection and the location of a particular fault. The faults considered in this work are additive, presented in the actuators of the proce (mas) ss and they represent a malfunction in the feeding flow pumps of the monomer towards the interior of the reactor. The observers used to generate residuals are one of the main advantages of the proposed method, these are easy to implement and have a simple calibration, which make their on-line application suitable. The effectiveness of this method was validated by simulation for the process of copolymerization in emulsion between butyl acrylate and styrene.

Scientific Electronic Library Online (Spanish)

3

Geometría y cinemática de la Zona de Cizalle Seno Arcabuz, Andes patagónicos, Chile

Olivares, Beatriz; Cembrano, José; Hervé, Francisco; López, Gloria; Prior, David
2003-01-01

Resumen en español La Zona de Cizalle Seno Arcabuz (ZCSA) de rumbo general nornoroeste yuxtapone dos unidades de rocas metamórficas de distintas edades y niveles estructurales en la isla Diego de Almagro (51°15'-51°40'S): una unidad occidental, de facies esquistos verdes y esquistos azules; y otra unidad oriental, de rocas metasedimentarias. Las rocas de la ZCSA están deformadas dúctilmente y presentan, al menos, dos eventos de deformación documentados por sendas fábricas coexistente (mas) s y sobrepuestas: una foliación y lineación milonítica tempranas y una foliación y lineación de bajo 'strain' tardías originadas por plegamiento de la fábrica milonítica. La lineación milonítica está bien preservada y posee buzamiento general hacia el norte (~40°). El grado metamórfico de la deformación corresponde a la facies esquistos verdes y se incrementa hacia el sur donde se encuentran rocas de más alto 'strain'. La deformación dúctil es de naturaleza triclínica, evidenciada por una lineación de estiramiento oblicua la que es típica de zonas de cizalle transpresionales. Así lo corroboran los indicadores cinemáticos, principalmente sinistrales inversos. Se proponen y discuten dos diferentes escenarios que dan cuenta de la relación espacial entre la ZCSA y los dos niveles estructurales yuxtapuestos: (1) La ZCSA es coetánea a la exhumación diferencial del bloque oeste, en cuyo caso las lineaciones minerales buzantes al norte se habrían formado durante este evento, lo que implicaría un movimiento sinistral inverso, consistente con la cinemática de la ZCSA. (2) La ZCSA no es coetánea a la exhumación, en este caso la zona de cizalle habría generado lineaciones minerales horizontales formadas durante un evento transcurrente sinistral y la exhumación habría ocurrido con posterioridad, debido a un basculamiento tectónico cuyo pivote estaría al norte de la zona de estudio Resumen en inglés Geometry and kinematics of Seno Arcabuz Shear Zone, Patagonian Andes, Chile. Metamorphic units of different age and structural levels occur at Isla Diego de Almagro (51°30'S), where they are juxtaposed by the Seno Arcabuz Shear Zone (SASZ). The SASZ strikes NNW and exposes deeper structural levels to the west of it. The SASZ rocks are ductilely deformed and document, at least, two deformation events evidenced by coexistent superposed fabrics. An early mylonitic foliation (mas) and lineation, and a late low strain foliation and lineation originated by folding of the early fabric. The mylonitic lineation is well preserved and plunges moderately to the north (ca. 40°); the rock strain and metamorphic grade increase progressively to the south. Ductile deformation is triclinic, as documented by oblique stretching lineations, typical of transpressional shear zones. Kinematic indicators, which are mainly sinistral-reverse, are consistent with bulk transpressional kinematics. According to field geology, shear zone kinematics and available geologic and chronologic data, two possible scenarios are proposed to account for the spatial relationship between the SASZ and the two different structural levels juxtaposed by it: (1) The SASZ is coeval with the differential exhumation of the western block, and then the north-plunging lineations formed during sinistral-reverse motion or (2) The SASZ is not coeval with differential exhumation of the western block, in such case the mylonitic lineation formed in a formerly sinistral strike-slip shear zone and the exhumation of the western block took place later, by block tilting to the north

Scientific Electronic Library Online (Spanish)

4

Tomography of high-redshift clusters with OSIRIS

Fernández-Soto, Alberto; Bland-Hawthorn, J.; González Serrano Moreno, José Ignacio; Carballo, R.
2003-03-20

Digital.CSIC (Spain)

6

Nonholonomic systems on Lie algebroids

Cortés, Jorge; León, Manuel de; Marrero, Juan Carlos; Martínez, Eduardo

To appear in Discrete and Continuous Dynamical Systems A.-- 56 pages.-- 2000 MSC Classes: 70F25, 70H03, 70H33, 37J60, 53D17. | This paper presents a geometric description on Lie algebroids of Lagrangian systems subject to nonholonomic constraints. The Lie algebroid framework provides a natural gener...

DRIVER (Spanish)

7

Nonholonomic systems on Lie algebroids

Cortés, Jorge; León, Manuel de; Marrero, Juan Carlos; Martínez, Eduardo
2008-04-28

Digital.CSIC (Spain)

8

Non-Hamiltonian Actions and Lie-Algebra Cohomology of Vector Fields

Ferreiro Pérez, Roberto; Muñoz Masqué, Jaime
2009-06-16

Digital.CSIC (Spain)

9

Linear almost Poisson structures and Hamilton-Jacobi theory. Applications to nonholonomic Mechanics

León, Manuel de; Marrero, Juan Carlos; Martín de Diego, David

36 pages, 1 figure.-- MSC classes: 70H20; 70F25; 70G45; 70H05. | In this paper, we study the underlying geometry in the classical Hamilton-Jacobi theory. The proposed formalism is also valid for nonholonomic systems. We first introduce the essential geometric ingredients: a vector bundle, a linear a...

DRIVER (Spanish)

10
11

Geometric principles of surface growth

Escudero, Carlos

PACS nrs.: 68.35.Fx; 02.40.Hw; 05.40.-a; 64.60.Ht.-- ArXiv pre-print available at: http://arxiv.org/abs/0811.2890 | I introduce a new equation describing epitaxial growth processes. This equation is derived from a simple variational geometric principle and it has a straightforward interpretation in ...

DRIVER (Spanish)

13

Functionally Graded Media

Campos, Cédric M.; Epstein, Marcelo; León, Manuel de

20 pages, 5 figures.-- MSC classes: 74B20 (Primary), 58H05 (Secondary), 53C10 | The notions of uniformity and homogeneity of elastic materials are reviewed in terms of Lie groupoids and frame bundles. This framework is also extended to consider the case Functionally Graded Media, which allows us to ...

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14

Functionally Graded Media

Campos, Cédric M.; Epstein, Marcelo; León, Manuel de
2007-11-16

Digital.CSIC (Spain)

15

Fourier-Mukai and Nahm transforms for holomorphic triples on elliptic curves

García Prada, Oscar; Hernández Ruipérez, Daniel; Pioli, Fabio; Tejero, Carlos

39 pages, LaTeX2e, no figures; new proofs added in Version nr. 2, some arguments rewritten and typos corrected. Final version to appear in Journal of Geometry and Physics. | We define a Fourier-Mukai transform for a triple consisting of two holomorphic vector bundles over an elliptic curve and a hom...

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16

Fourier-Mukai and Nahm transforms for holomorphic triples on elliptic curves

García Prada, Oscar; Hernández Ruipérez, Daniel; Pioli, Fabio; Tejero, Carlos
2004-12-22

Digital.CSIC (Spain)

19

Children's Gestures from 18 to 30 months

Andrén, Mats

This thesis concerns the nature of the gestures performed by five Swedish children. The children are followed from 18 to 30 months of age: an age range which is characterized by a rapid succession of developmental changes in children's abilities to communicate by means of both spoken language and ge...

DRIVER (Spanish)

20

Causal structure of acoustic spacetimes

Barceló, Carlos; Liberati, Stefano; Sonego, Sebastiano; Visser, Matt
2004-09-01

Digital.CSIC (Spain)

22

A new geometric setting for classical field theories

León, Manuel de; Marrero, Juan Carlos; Martín de Diego, David

"The paper is in final form and no version of it will be published elsewhere". | A new geometrical setting for classical field theories is introduced. This description is strongly inspired in the one due to Skinner and Rusk for singular lagrangians systems. For a singular field theory a constraint a...

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23

A new geometric setting for classical field theories

León, Manuel de; Marrero, Juan Carlos; Martín de Diego, David
2002-02-07

Digital.CSIC (Spain)