2,531 research outputs found
Three Hopf algebras from number theory, physics & topology, and their common background II: general categorical formulation
We consider three a priori totally different setups for Hopf algebras from number theory, mathematical physics and algebraic topology. These are the Hopf algebra of Goncharov for multiple zeta values, that of Connes-Kreimer for renormalization, and a Hopf algebra constructed by Baues to study double loop spaces. We show that these examples can be successively unified by considering simplicial objects, co-operads with multiplication and Feynman categories at the ultimate level. These considerations open the door to new constructions and reinterpretations of known constructions in a large common framework which is presented step-by-step with examples throughout. In this second part of two papers, we give the general categorical formulation
Isolated singularities of the prescribed mean curvature equation in Minkowski -space
We give a classification of non-removable isolated singularities for real
analytic solutions of the prescribed mean curvature equation in Minkowski
-space
The Codazzi Equation for Surfaces
In this paper we develop an abstract theory for the Codazzi equation on
surfaces, and use it as an analytic tool to derive new global results for
surfaces in the space forms {\bb R}^3, {\bb S}^3 and {\bb H}^3. We give
essentially sharp generalizations of some classical theorems of surface theory
that mainly depend on the Codazzi equation, and we apply them to the study of
Weingarten surfaces in space forms. In particular, we study existence of
holomorphic quadratic differentials, uniqueness of immersed spheres in
geometric problems, height estimates, and the geometry and uniqueness of
complete or properly embedded Weingarten surfaces
Failure and impact behavior of facade panels made of glass fiber reinforced cement(GRC)
GRC is a cementitious composite material made up of a cement mortar matrix and chopped glass fibers. Due to its outstanding mechanical properties, GRC has been widely used to produce cladding panels and some civil engineering elements. Impact failure of cladding panels made of GRC may occur during production if some tool falls onto the panel, due to stone or other objects impacting at low velocities or caused by debris projected after a blast. Impact failure of a front panel of a building may have not only an important economic value but also human lives may be at risk if broken pieces of the panel fall from the building to the pavement. Therefore, knowing GRC impact strength is necessary to prevent economic costs and putting human lives at risk.
One-stage light gas gun is an impact test machine capable of testing different materials subjected to impact loads. An experimental program was carried out, testing GRC samples of five different formulations, commonly used in building industry. Steel spheres were shot at different velocities on square GRC samples. The residual velocity of the projectiles was obtained both using a high speed camera with multiframe exposure and measuring the projectile’s penetration depth in molding clay blocks. Tests were performed on young and artificially aged GRC samples to compare GRC’s behavior when subjected to high strain rates. Numerical simulations using a hydrocode were made to analyze which parameters are most important during an impact event.
GRC impact strength was obtained from test results. Also, GRC’s embrittlement, caused by GRC aging, has no influence on GRC impact behavior due to the small size of the projectile. Also, glass fibers used in GRC production only maintain GRC panels’ integrity but have no influence on GRC’s impact strength. Numerical models have reproduced accurately impact tests
Hibridaciones de género en el videoarte español
Comunicaciones del IV Congreso Internacional sobre análisis fĂlmico celebrado en la Universitat Jaume I de CastellĂłn 4,5 y 6 de mayo de 201
The right to sufragge in the xxth century
En el presente trabajo se aborda el estudio del derecho de sufragio en el siglo
XX, aquel en el que se expande con fuerza y se consolida de manera irreversible
con el carácter de fundamental. Y se hace desde una perspectiva, no solo histórica,
sino también general y comparada, pues toma como base el significado y
evoluciĂłn del sufragio en el conjunto de los paĂses occidentales en un determinado
momento histórico, sin perjuicio de constantes referencias al caso español
y a otras épocas pasadas y aún posteriores. El análisis se articula en torno a
tres cuestiones básicas: la delimitación básica de la naturaleza del derecho de
sufragio, el principio de universalidad del mismo y las limitaciones que ha experimentado
durante el siglo XX.This paper deals with the study of the right of suffrage in the twentieth century,
which has strongly grown and irreversibly consolidated with the character of
fundamental right. And the perspective is not only historical, but also global
and comparative, since its ground it’s the meaning and evolution of suffrage
in Western countries as a whole in a particular historical moment, thought
there are constant references to the Spanish case and other past and even later
historical stages. The analysis is organized around three basic issues: the basic
definition of the nature of the right to suffrage, its principle of universality and
the limitations experienced during the twentieth century
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