Cosmic magnetic fields and dark energy in extended electromagnetism

We discuss an extended version of electromagnetism in which the usual gauge fixing term is promoted into a physical contribution that introduces a new scalar state in the theory. This new state can be generated from vacuum quantum fluctuations during an inflationary era and, on super-Hubble scales, gives rise to an effective cosmological constant. The value of such a cosmological constant coincides with the one inferred from observations as long as inflation took place at the electroweak scale. On the other hand, the new state also generates an effective electric charge density on sub-Hubble scales that produces both vorticity and magnetic fields with coherent lengths as large as the present Hubble horizon.Comment: 4 pages, 2 figures. Contribution to the proceedings of Spanish Relativity Meeting 2010, Granada, Spain, 6-10 September 201

Vida y muerte en la Inclusa de Madrid en el primer año de posguerra

Tras finalizar la Guerra Civil buena parte de la población española, sobre todo los habitantes de las grandes ciudades se vieron abocados a una política de supervivencia, para vencer el hambre, la miseria y la desolación. Uno de los conjuntos poblacionales más castigado, fue sin duda la infancia, y dentro de este grupo, el exponente más claro de la degradación a la que se llegó fueron los niños abandonados. En el «año de la victoria» Madrid abandonó a muchos niños, unos fueron acogidos en Auxilio Social (organización falangista realizada a imagen y semejanza de la organización nazi winterhilfe) mientras que otros fueron asilados en una institución de gran tradición en la capital de España: la Inclusa. Este articulo analiza la situación de los niños que fueron abandonados en el Instituto Provincial de Puericultura (como así se denominaba) dependiente de la Excelentísima Diputación Provincial Madrileña durante el periodo comprendido entre el 1 de abril de 1939 y el 31de marzo de 1940 el primer año de posguerra. After finishing the Civil war, a great part of the Spanish population, especially the inhabitants of the big cities were doomed to the politics of survival, to conquer the hunger, the misery and the desolation. One of the population sets at harshly punished, was undoubtedly infants, and inside this group, the clearest exponent of the degradation was visible by those who were abandoned. In the «year of the victory» the people of Madrid abandoned many children, some were received in Social Aid (Falangist organization formed in the image of similar to the Nazi winterhilfe organization) whereas others were sheltered in an institution of great tradition in the capital of Spain: the Inclusa. This article analyses the situation of the children who were recieved in the Provincial Institute of Puericulture (this is what it is known as) belonging to Diputacion Provincial of Madrid during this period between April 1, 1939 and March 31, 1940; the first year of this post war period

Mobile device-based Bluetooth Low Energy Database for range estimation in indoor environments

The demand to enhance distance estimation and location accuracy in a variety of Non-Line-of-Sight (NLOS) indoor environments has boosted investigation into infrastructure-less ranging and collaborative positioning approaches. Unfortunately, capturing the required measurements to support such systems is tedious and time-consuming, as it requires simultaneous measurements using multiple mobile devices, and no such database are available in literature. This article presents a Bluetooth Low Energy (BLE) database, including Received-Signal-Strength (RSS) and Ground-Truth (GT) positions, for indoor positioning and ranging applications, using mobile devices as transmitters and receivers. The database is composed of three subsets: one devoted to the calibration in an indoor scenario; one for ranging and collaborative positioning under Non-Line-of-Sight conditions; and one for ranging and collaborative positioning in real office conditions. As a validation of the dataset, a baseline analysis for data visualization, data filtering and collaborative distance estimation applying a path-loss based on the Levenberg-Marquardt Least Squares Trilateration method are included

Influence of Clocking Strategies on the Design of Low Switching-Noise Digital and Mixed-Signal VLSI Circuits

This communication shows the influence of clocking schemes on the digital switching noise generation. It will be shown how the choice of a suited clocking scheme for the digital part reduces the switching noise, thus alleviating the problematic associated to limitations of performances in mixed-signal Analog/Digital Integrated Circuits. Simulation data of a pipelined XOR chain using both a single-phase and a two-phase clocking schemes, as well as of two nbit counters with different clocking styles lead, as conclusions, to recommend multiple clock-phase and asynchronous styles for reducing switching noise

Damage tolerance assessment by bend and shear tests of two multilayer composites: Glass fibre reinforced metal laminate and aluminium roll-bonded laminate

The damage tolerance of an aluminium roll-bonded laminate (ALH19) and a glass fibre reinforced laminate (GLARE) (both based in Al 2024-T3) has been studied. The composite laminates have been tested under 3-point bend and shear tests on the interfaces to analyze their fracture behaviour. During the bend tests different fracture mechanisms were activated for both laminates, which depend on the constituent materials and their interfaces. The high intrinsic toughness of the pure Al 1050 layers present in the aluminium roll-bonded laminate (ALH19), together with extrinsic toughening mechanisms such as crack bridging and interface delamination were responsible for the enhanced toughness of this composite laminate. On the other hand, crack deflection by debonding between the glass fibres and the plastic resin in GLARE, was the main extrinsic toughening mechanism present in this composite laminateFinancial support from CICYT (Project MAT2003-01172) is gratefully acknowledged. C.M. Cepeda-Jiménez thanks the Spanish Ministry of Education and Science for a Juan de la Cierva contract. Authors also thank Delft University of Technology for providing the GLARE.Peer reviewe

Reconocimiento de actividades en el desplazamiento por interiores mediante un teléfono inteligente y señales de oportunidad

[Resumen] En este trabajo se estudia cómo las señales de oportunidad pueden ser utilizadas no sólo para mejorar la precisión del posicionamiento en interiores, sino también para obtener información valiosa de las actividades que está realizando el usuario. Las señales de oportunidad son aquellas no diseñadas específicamente para posicionamiento, pero presentes de forma natural en muchos entornos, y que pueden ser captadas, por ejemplo, a través de los sensores con los que cuenta cualquier teléfono móvil actual. Se introducen diferentes posibilidades de las señales de oportunidad, dentro de un marco de estimación de la posición bayesiano, y se ilustra su utilidad mediante trayectorias reales realizadas en un edificio de gran tamaño.Este trabajo ha sido financiado por los proyectos LORIS (MINECO ref. TIN2012-38080-C04) y TARSIUS (MINECO/FEDER ref. TIN2015-71564-C4-2-R)https://doi.org/10.17979/spudc.978849749808

Reversal of gulf stream circulation in a vertically vibrated triangular fluidized bed

Proceeding of: Fifteenth International Conference on Fluidization, Fluidization XV, Fluidization for Emerging Green Technologies, Montebello, Canada, May 22nd to 27th, 2016The present work experimentally assesses the effect of vibration on the dynamics of particles in a fluidized bed of triangular shape. The base of the bed is composed of two inclined walls, each one forming an angle of 45 with the horizontal. The bed has 0.206 m span and 0.01 m thickness. The bed vessel is made of antistatic PMMA in order to allow optical access with a high-speed camera. The bed is mounted on an electrodynamic shaker which produces vertical vibration. The bed material is ballotini particles with a mean diameter of 1.15 mm up to the top of the inclined walls. Air was injected through the inclined bed walls to fluidize the bed to explore whether vibration of the bed vessel together with gas injection can make the dynamics of this bed different to that found when no gas is injected. A high speed camera was used to record the motion of particles in the bed. The velocity of the particles in the bed was obtained via Particle Image Velocimetry (PIV). The results show that several circulation patterns are observed as a function of vibration amplitude and frequency when the fluidization velocity is just below and above the minimum fluidization velocity. Noticeably, for zero gas velocity, particles ascend close to the side walls and descend in the center of the bed. By injecting fluidization gas, the circulation pattern of the bed can be reversed (i.e. particles descending near the inclined walls and ascending in the center of the bed). Conditions for which this reversal of the gulf stream circulation of particles appears in the triangular bed are explored in this work and these include gas superficial velocities higher than the minimum fluidization velocity and sufficiently high values of the vibration strength.This work has been partially funded by the Universidad Carlos IIIde Madrid (Ayudas a la movilidad 2015) and by the Spanish Ministry of Economy and Competitiveness (project ENE2015/00188/001)

A tripartite filter design for seamless pedestrian navigation using recursive 2-means clustering and Tukey update

Mobile devices are desired to guide users seamlessly to diverse destinations indoors and outdoors. The positioning fixing subsystems often provide poor quality measurements with gaps in an urban environment. No single position fixing technology works continuously. Many sensor fusion variations have been previously trialed to overcome this challenge, including the particle filter that is robust and the Kalman filter which is fast. However, a lack exists, of context aware, seamless systems that are able to use the most fit sensors and methods in the correct context. A novel adaptive and modular tripartite navigation filter design is presented to enable seamless navigation. It consists of a sensor subsystem, a context inference and a navigation filter blocks. A foot-mounted inertial measurement unit (IMU), a Global Navigation Satellite System (GNSS) receiver, Bluetooth Low Energy (BLE) and Ultrawideband (UWB) positioning systems were used in the evaluation implementation of this design. A novel recursive 2-means clustering method was developed to track multiple hypotheses when there are gaps in position fixes. The closest hypothesis to a new position fix is selected when the gap ends. Moreover, when the position fix quality measure is not reliable, a fusion approach using a Tukey-style particle filter measurement update is introduced. Results show the successful operation of the design implementation. The Tukey update improves accuracy by 5% and together with the clustering method the system robustness is enhanced

New CMOS VLSI Linear Self-Timed Architectures

The implementation of digital signal processor circuits via self-timed techniques is currently a valid altemative to solve some problems encountered in synchronous VLSI circuits. However; a main difference between synchronous and asynchronous circuits is the hardware resources needed to implement asynchronous circuits. This communication presents four less-costly alternatives to a previously reported linear selftimed architecture, and their application in the design of FIFO memories. Furthermore, the integration and characterization in the laboratory of prototypes of these FIFOs are presented