131,947 research outputs found
Intermittenza e Interferenza
No full textIl contributo ripercorre l'impostazione teorica sottesa all'elaborazione delle sperimentazioni progettuali sul tema dell'abitare condotte dagli studenti napoletani nell'ambito del seminario itinerante di progettazione architettonica Villard 11. Le specificità del contesto romano dell'area portuale ostiense sono considerate come opportunità per implementare le abitazioni con servizi aperti al quartiere
Harris Galante cementless acetabular replacement in avascular necrosis
No full textWe describe the results of 76 total arthroplasties of the hip for stage-III or stage-IV avascular necrosis of the femoral head. Harris Galante Porous cups were used in 63 patients between 1986 and 1994 and followed prospectively. We reviewed 70 hips with a follow-up of more than five years (mean 7.6). At the latest review the mean Harris Hip Score had improved from a preoperative value of 29 +/- 14.7 to 94 +/- 6.8. Radiologically, there was no evidence of acetabular migration. The rate of revision for the femoral component was 8.6%, three being undertaken for loosening and three to allow downsizing of the femoral head. The rate of revision for the acetabular component was 7.1% (five cups). At the time of revision none of the cups was clinically loose, and only required the liner to be changed. The rate of complications was low with no case of deep infection or dislocation, but nine of the 76 hips (11.8%) showed grade-III heterotopic ossification. Previous studies of patients undergoing cemented total hip arthroplasty for the treatment of advanced avascular necrosis have indicated a high incidence of loosening of the acetabular component. Our findings show good medium-term results using the Harris Galante Porous cup for acetabular reconstruction, together with a variety of cemented femoral components, for the treatment of this difficult problem
Modified special relativity on a fluctuating spacetime
No full textIt was recently proposed that deformations of the relativistic symmetry, as those considered in deformed
special relativity (DSR), can be seen as the outcome of a measurement theory in the presence of nonnegligible
(albeit small) quantum gravitational fluctuations [S. Liberati, S. Sonego, and M. Visser, Phys.
Rev. D 71, 045001 (2005).][R. Aloisio, A. Galante, A. Grillo, S. Liberati, E. Luzio, and F. Mendez, Phys.
Rev. D 73, 045020 (2006).]. In this paper we explicitly consider the case of a spacetime described by a flat
metric endowed with stochastic fluctuations and, for a free particle, we show that DSR-like nonlinear
relations between the spaces of the measured and classical momenta, can result from the average of the
stochastic fluctuations over a scale set to be the de Broglie wavelength of the particle. As illustrative
examples we consider explicitly the averaging procedure for some simple stochastic processes and discuss
the physical implications of our results
Modified Special Relativity on a fluctuating spacetime
No full textIt was recently proposed that deformations of the relativistic symmetry, as those considered in deformed special relativity (DSR), can be seen as the outcome of a measurement theory in the presence of non-negligible (albeit small) quantum gravitational fluctuations [S. Liberati, S. Sonego, and M. Visser, Phys. Rev. D 71, 045001 (2005).][R. Aloisio, A. Galante, A. Grillo, S. Liberati, E. Luzio, and F. Mendez, Phys. Rev. D 73, 045020 (2006).]. In this paper we explicitly consider the case of a spacetime described by a flat metric endowed with stochastic fluctuations and, for a free particle, we show that DSR-like nonlinear relations between the spaces of the measured and classical momenta, can result from the average of the stochastic fluctuations over a scale set to be the de Broglie wavelength of the particle. As illustrative examples we consider explicitly the averaging procedure for some simple stochastic processes and discuss the physical implications of our results
The GALANTE photometric system
No full textThis paper describes the characterization of the GALANTE photometric system, a seven intermediate-and narrow-band filter system with a wavelength coverage from 3000 Å to 9000 Å. We describe the photometric system presenting the full sensitivity curve as a product of the filter sensitivity, CCD, telescope mirror, and atmospheric transmission curves, as well as some first-and second-order moments of this sensitivity function. The GALANTE photometric system is composed of four filters from the J-PLUS photometric system, a twelve broad-to-narrow filter system, and three exclusive filters, specifically designed to measure the physical parameters of stars such as effective temperature T, log (g), metallicity, colour excess E(4405-5495), and extinction type R. Two libraries, the Next Generation Spectral Library (NGSL) and the one presented in Maíz Apellániz & Weiler (2018), have been used to determine the transformation equations between the Sloan Digital Sky Survey (SDSS) ugriz photometry and the GALANTE photometric system. We will use this transformation to calibrate the zero-points of GALANTE images. To this end, a preliminary photometric calibration of GALANTE has been made based on two different griz libraries (SDSS DR12 and ATLAS All-Sky Stellar Reference Catalog, hereinafter RefCat2). A comparison between both zero-points is performed leading us to the choice of RefCat2 as the base catalogue for this calibration, and applied to a field in the Cyg OB2 association.© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.AL-G, EJA, and JMA acknowledge support from the Spanish Government Ministerio de Ciencia, Innovacion y Universidades though grants AYA2013-40 611-P and AYA2016-75 931-C2-1/2-P. A.L.-G and EJA also acknowledge support from the State Agency for Research of the Spanish MCIU through the 'Center of Excellence Severo Ochoa' award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709).Peer Reviewe
Scalable Layer-2/Layer-3 Multistage Switching Architectures for Software Routers
No full textSoftware routers are becoming an important alternative to proprietary and expensive network devices, because they exploit the economy of scale of the PC market and open-source software. When considering maximum performance in terms of throughput, PC-based routers suffer from limitations stemming from the single PC architecture, e.g., limited bus bandwidth, and high memory access latency. To overcome these limitations, in this paper we present a multistage architecture that combines a layer-2 load-balancer front-end and a layer-3 routing back-end, interconnected by standard Ethernet switches. Both the front-end and the back-end are implemented using standard PCs and open- source software. After describing the architecture, evaluation is performed on a lab test-bed, to show its scalability. While the proposed solution allows to increase performance of PC- based routers, it also allows to distribute packet manipulation functionalities, and to automatically recover from component failures
Lo stretto
No full textIl contributo esamina la forma geografica dello stretto di Messina traendo informazioni per un progetto urbano di ricostruzione del significato degli insediamenti urbani
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