1,344 research outputs found
Non-monotonic entanglement of physical EM field states in non-inertial frames
We develop a general technique to analyse the quantum effects of acceleration
on realistic spatially-localised electromagnetic field states entangled in the
polarization degree of freedom. We show that for this setting, quantum
entanglement may build up as the acceleration increases, providing a clear
signature of the quantum effects of relativistic acceleration.Comment: 5 pages, 3 figure
Estimativos del error a posteriori para problemas de valores iniciales no lineales en el contexto de los espacios de Banach y los semigrupos
Un discretización en tiempo basada en el método de Euler regresivo para el problema parab´olico no lineal abstracto
u = F(u), u(0) = u0,
es considerada. En el presente trabajo se obtienen estimativos a posteriori para la citada discretización en tiempo en el marco de los espacios de Banach, los semigrupos y la regularidad maximal. Los estimativos obtenidos resultan ser de tipo condicional, es decir están sujetos a hipótesis que son verificables en la práctica como son las condiciones sobre la propia solución numérica
Entanglement of arbitrary spin fields in noninertial frames
We generalize the study of fermionic and bosonic entanglement in noninertial frames to fields of arbitrary spin and beyond the single-mode approximation. After the general analysis we particularize for two interesting cases: entanglement between an inertial and an accelerated observer for massless fields of spin 1 (electromagnetic) and spin 3/2 (Rarita-Schwinger). We show that, in the limit of infinite acceleration, no significant differences appear between the different spin fields for the states considered. © 2011 American Physical Society.s. E. M.-M. was supported by a CSIC Grant No. JAE-PREDOC2007 and by the Spanish MICINN Project No. FIS2008-05705/FIS and the QUITEMAD consortium.Peer Reviewe
Wind Field Diagnostic Model
[EN]This chapter describes Wind3D, a mass-consistent diagnostic model with an updated vertical wind profile and atmospheric parameterization. First, a description of Wind3D is provided, along with their governing equations. Next, the finite element formulation of the model and the description of the solver of the corresponding linear system are presented. The model requires an initial wind field, interpolated from data obtained in a few points of the domain. It is constructed using a logarithmic wind profile that considers the effect of both stable boundary layer (SBL) and the convective boundary layer (CBL). One important aspect of mass-consistent models is that they are quite sensitive to the values of some of their parameters. To deal with this problem, a strategy for parameter estimation based on a memetic algorithm is presented. Finally, a numerical experiment over complex terrain is presented along with some concluding remarks
Three-dimensional finite element modelling of stack pollutant emissions
In this paper we propose a finite element method approach formodelling the air quality in a local scale over complex terrain. The area of interest is up to tens of kilometres and it includes pollutant sources. The proposed methodology involves the generation of an adaptive tetrahedral mesh, the computation of an ambient wind field, the inclusion of the plume rise effect in the wind field, and the simulation of transport and reaction of pollutants. The methodology is used to simulate a fictitious pollution episode in La Palma island (Canary Island, Spain).Peer ReviewedPostprint (published version
Enhanced manufacturing storage management using data mining prediction techniques
Performing an efficient storage management is a key issue for reducing costs in the manufacturing process. And the first step to accomplish this task is to have good estimations of the consumption of every storage component.
For making accurate consumption estimations two main approaches are possible: using past utilization values (time series); and/or considering other external factors affecting the spending rates.
Time series forecasting is the most common approach due to the fact that not always is clear the causes affecting consumption. Several classical methods have extensively been used, mainly ARIMA models.
As an alternative, in this paper it is proposed to use prediction techniques based on the data mining realm.
The use of consumption prediction algorithms clearly increases the storage management efficiency. The predictors based on data mining can offer enhanced solutions in many cases.Telefónica, through the “Cátedra de Telefónica Inteligencia en la Red”Paloma Luna Garrid
El Taller lítico LY 041-La Divisoria (Departamento Pilcaniyeu, Provincia de Río Negro)
En el taller lítico LY 041-La Divisoria, situado en el sudoeste de la estepa rionegrina, se
prepararon artefactos bifaciales en rocas dacíticas procedentes de la cercana cantera Paso
Limay. Habría sido un satélite del alero Carriqueo, un pequeño sitio de vivienda muy
próximo, del cual se habrían segregado algunas tareas de talla, que generan muchos
desechos potencialmente molestos o peligrosos. Además, desde el sitio se tiene buena
visibilidad del paisaje. Subsidiariamente, en LY 041-La Divisoria se habrían realizado
algunas tareas de procesamiento de materiales orgánicos.
Este sitio corrobora que para los cazadores-recolectores de la comarca, la cantera Paso
Limay tuvo un papel central en el aprovisionamiento de roca para puntas de proyectil.LY 041-La Divisoria is a lithic workshop in the southwestern steppe of the Río Negro
Province, Argentina, where dacite brought from the Paso Limay quarry was reduced
bifacially.
This workshop would have been a satellite of close-by Carriqueo rockshelter, a small
living cite from which certain tasks were sometimes shifted because they generated
encumbering refuse. LY 041-La Divisoria provided also a good view of the environment.
Subsidiarily, some processing of organic materials was carried out.
LY 041-La Divisoria corroborates that for the local hunter-gatherers, the Paso Limay
quarry was of major importance for the provisioning of raw material for projectile-points.Fil: Crivelli Montero, Eduardo A. .
Universidad de Buenos AiresFil: Ramos, Mariano S. .
Universidad Nacional de Lujá
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