Diffusion dynamics on multiplex networks

We study the time scales associated to diffusion processes that take place on multiplex networks, i.e. on a set of networks linked through interconnected layers. To this end, we propose the construction of a supra-Laplacian matrix, which consists of a dimensional lifting of the Laplacian matrix of each layer of the multiplex network. We use perturbative analysis to reveal analytically the structure of eigenvectors and eigenvalues of the complete network in terms of the spectral properties of the individual layers. The spectrum of the supra-Laplacian allows us to understand the physics of diffusion-like processes on top of multiplex networks.Comment: 6 Pages including supplemental material. To appear in Physical Review Letter

A Semantically Enhanced UPnP Control Point for Sharing Multimedia Content

The Universal Plug and Play (UPnP) protocol lets users share multimedia content across devices and display it in multimedia renderers in homebased LANs. However, UPnP doesn’t support sharing this content between homes (for example, with friends, relatives, or workmates), and content can be difficult to find. A UPnP extension provides uniform access to multimedia content belonging to different homes, such as content from a user’s Facebook friends. In addition, an extended UPnP control point lets users add semantic annotations to their multimedia resources and link them to the linked data cloud to facilitate their discovery by others

Towards a Catalog of OWL-based Ontology Design Patterns

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Electro-optical characterization of IC compatible microcantilevers

The aim of this work is to simulate and optically characterize the piezoelectric performance of complementary metal oxide semiconductor (CMOS) compatible microcantilevers based on aluminium nitride (AlN) and manufactured at room temperature. This study should facilitate the integration of piezoelectric micro-electro-mechanical systems (MEMS) such as microcantilevers, in CMOS technology. Besides compatibility with standard integrated circuit manufacturing procedures, low temperature processing also translates into higher throughput and, as a consequence, lower manufacturing costs. Thus, the use of the piezoelectric properties of AlN manufactured by reactive sputtering at room temperature is an important step towards the integration of this type of devices within future CMOS technology standards. To assess the reliability of our fabrication process, we have manufactured arrays of free-standing microcantilever beams of variable dimension and studied their piezoelectric performance. The characterization of the first out-of-plane modes of AlN-actuated piezoelectric microcantilevers has been carried out using two optical techniques: laser Doppler vibrometry (LDV) and white light interferometry (WLI). In order to actuate the cantilevers, a periodic chirp signal in certain frequency ranges was applied between the device electrodes. The nature of the different vibration modes detected has been studied and compared with that obtained by a finite element model based simulation (COMSOL Multiphysics), showing flexural as well as torsional modes. The correspondence between theoretical and experimental data is reasonably good, probing the viability of this high throughput and CMOS compatible fabrication process. To complete the study, X-ray diffraction as well as d33 piezoelectric coefficient measurements were also carried out

Testing for private information using trade duration models with unobserved market heterogeneity: The case of Banco Popular

In this paper, we attempt to assess the potential importance of different types of traders (i.e., those with public and private information) in financial markets using a specification of the standardized duration. This approach allows us to test unobserved heterogeneity in a nonlinear version based on a self-exciting threshold autoregressive conditional duration model. We illustrate the relevance of this procedure for identifying the presence of private information in the final days of trading of Banco Popular, the first bank rescued by the European Single Resolution Board

Semantically enabling UPnP Networks of Multimedia Home Content

There is plenty of multimedia content available in our homes, stored in multimedia disk drives, personal computers, or digital cameras. Protocols like Universal Plug and Play (UPnP) allow sharing this content among storage devices and displaying them in multimedia renderers in the local area networks of our homes. However, UPnP does not provide native support for the exchange of resources across homes neither does it provide means to describe multimedia content so as to facilitate search across multimedia resources. In this paper we describe a set of extensions to the UPnP protocol to provide a uniform access to multimedia content belonging to different homes, as well as mechanisms to create tag-based and ontology-based metadata, allowing search and Linked-Data publishing of these multimedia resources

Spike-based VITE control with Dynamic Vision Sensor applied to an Arm Robot.

Spike-based motor control is very important in the field of robotics and also for the neuromorphic engineering community to bridge the gap between sensing / processing devices and motor control without losing the spike philosophy that enhances speed response and reduces power consumption. This paper shows an accurate neuro-inspired spike-based system composed of a DVS retina, a visual processing system that detects and tracks objects, and a SVITE motor control, where everything follows the spike-based philosophy. The control system is a spike version of the neuroinspired open loop VITE control algorithm implemented in a couple of FPGA boards: the first one runs the algorithm and the second one drives the motors with spikes. The robotic platform is a low cost arm with four degrees of freedom.Ministerio de Ciencia e Innovación TEC2009-10639-C04-02/01Ministerio de Economía y Competitividad TEC2012-37868-C04-02/0

Análisis DEA de los proveedores de servicios de navegación aérea en el marco de cielo único europeo

Una de las últimas medidas acometidas dentro del marco del programa de Cielo Único Europeo ha sido el desarrollo de un sistema de evaluación de rendimiento (eficiencia) de los servicios de navegación aérea y de las funciones de red en cuatro ámbitos clave: la seguridad, el medio ambiente, la capacidad y la rentabilidad (cost - efficiency). El sistema de evaluación establece en cada ámbito "indicadores" y "objetivos obligatorios"; y para alcanzar estos objetivos los Estados europeos deben establecer "planes de rendimiento" y "sistemas de incentivos". Este articulo realiza un análisis comparativo de la eficiencia y la productividad de los proveedores de servicios de navegación europeos, para determinar el posicionamiento inicial relativo de cada uno de ellos en términos de eficiencia, su potencial para alcanzar unos objetivos de rendimiento específicos, y como de cerca o lejos se encuentra cada organización respecto del nivel optimo de eficiencia determinado por el más eficiente de sus semejantes. El trabajo utiliza el análisis de envolvente de datos o DEA, una técnica de programación matemática no paramétrica, basada en la obtención de una frontera de eficiencia a partir de un conjunto de observaciones sin necesidad de conocer ninguna forma de relación funcional entre inputs y outputs.One of the last measures undertaken within the framework of the Single European Sky program has been the development of a performance evaluation framework (efficiency) of Air Navigation Services and network functions in four key areas: safety, environment, capacity and cost-efficiency. The evaluation framework establish "indicators" and "binding targets" and to achieve these objectives the European states must define "performance plans" and "incentive systems". This article makes a comparative analysis of the efficiency and productivity of the Air Navigation Service Providers in Europe, to determine the initial position on each of them in terms of efficiency, the potential for achieving specific performance targets, and how near or far is each organization from the optimal level of efficiency determined by the most efficient among their peers. The study uses data envelopment analysis or DEA, a nonparametric mathematical programming technique, based on obtaining an efficient frontier from a set of observations without knowing any form of functional relationship between inputs and outputs.Grupo de Transporte Aéreo - Grupo de Ingeniería Aplicada a la Industri