401 research outputs found
Sincronización y Estimación de canal eficiente y robusta en sistemas CoMP OFDM
Este trabajo fue presentado en el XXIX Simposium Nacional de la Unión Científica Internacional de Radio, celebrado los días 3-5 de septiembre de 2014 en la Universidad Politécnica de Valencia (España).In this paper, an efficient and robust simultaneous timing synchronization and channel estimation method for Cooperative MultiPoint Transmission and Reception (CoMP) is proposed. Efficiency is obtained by using the same two Orthogonal Frequency Division Multiplexing (OFDM) symbols for simultaneously transmitting preambles by all the base stations. Robustness is achieved by specially designed orthogonal sequences both in time and frequency domain. The proposed method is able to estimate the channels from several base stations without losing anything in performance with respect to the single transmission scenario. Furthermore, our proposed synchronization outperforms single transmitter methods and so, it could also be adapted for single base station OFDM systems.Este trabajo ha sido financiado parcialmente por los proyectos
GRE3NSYST (TEC2011-29006-C03-03) y COMONSENS
(CSD2008-00010).Publicad
Using FPGA for visuo-motor control with a silicon retina and a humanoid robot
The address-event representation (AER) is a
neuromorphic communication protocol for transferring
asynchronous events between VLSI chips. The event
information is transferred using a high speed digital parallel
bus. This paper present an experiment based on AER for
visual sensing, processing and finally actuating a robot. The
AER output of a silicon retina is processed by an AER filter
implemented into a FPGA to produce a mimicking behaviour
in a humanoid robot (The RoboSapiens V2). We have
implemented the visual filter into the Spartan II FPGA of the
USB-AER platform and the Central Pattern Generator (CPG)
into the Spartan 3 FPGA of the AER-Robot platform, both
developed by authors.Unión Europea IST-2001-34124 (CAVIAR)Ministerio de Ciencia y Tecnología TIC-2003-08164-C03-0
Capacidad de realizar esprints repetidos en jugadores profesionales de fútbol vs. Fútbol sala
Objetivo: Investigar los cambios producidos ante acciones de esprines repetidos (20+20 metros con cambio de dirección ), el CMJ, la respuesta metabólica (lactato) , y la relación entre estas variables y la fuerza y resistencia en jugadores profesionales de fútbol y fútbol sala. Métodos: Jugadores profesionales (n=30, doce de fútbol sala y veinte de fútbol) completaron tres sesiones de evaluación; VO2max en tapiz rodante, el salto CMJ y la RM en sentadilla completa y finalmente, se realizó el test de RSA (6 x 40 (20+20)). Resultados: Se obtuvieron valores similares de fuerza en sentadilla, en CMJ, de LAC después de la prueba RSA y de VO2max ( 95,12 kg vs 94,73 kg ; 34,5 cm vs 35,9 cm ; 13,65 mmol vs 14,33 mmol ; 62,78 ml·kg·min-1 vs . 62,95 ml·kg·min-1 fútbol vs. fútbol sala, respectivamente). Se obtuvieron diferencias significativas cuando se analizó la pérdida de rendimiento en velocidad (total y entre los tres primeros y tres últimos bloques de esprines) y en salto (2,67% vs 4,4%**; 1,28% vs 2,1%*; 2,88% vs 6,1%**; 9,71% vs 14,3%* de fútbol vs. fútbol sala, respectivamente). Conclusiones: Ambos deportes presentan diferencias significativas en las pérdidas de rendimiento en velocidad y salto a pesar de tener valores similares de fuerza, de VO2max, de lactato tras RSA y de CMJ. Podría atribuirse a los esfuerzos propios de cada deporte y puede sugerir que debería incrementarse el volumen de entrenamiento orientado a la capacidad de realizar esfuerzos repetidos frente a otro tipo de objetivo como la mejora de la capacidad aeróbica, sobre todo a nivel profesional.To investigate the changes through repeated explosive effort sequences (20+20-m sprint with change of direction), jumping, metabolic response (lactate), as well as the relationship between these variables and fitness qualities (strength and endurance) in professional futsal and soccer players. Methods: Male players (n =30, Twelve futsal and twenty soccer players) completed three testing sessions. In the first session was measured VO2max on a motorized treadmill. In the second session was measured counter movement jump (CMJ) and full squat RM in Smith Machine. Finally, in the third session six repeated-explosive effort sequences (RES) was performed. Results: Similar values of lower limbs strength, CMJ height, LAC after RSA test and VO2max (95,12 vs. 94,73; 34,5 vs. 35,9; 13,65 vs. 14,33; 62,78 vs. 62,95 soccer vs. futsal respectively) and significant differences when are analysed the loss of performance in velocity (total and between three first and three last) and vertical jump height (2,67 vs. 4,4**; 1,28 vs. 2,1*; 2,88 vs. 6,1**; 9,71 vs. 14,3* soccer vs. futsal respectively). Conclusions: Professional futsal and soccer obtain significant differences in speed and vertical jump height (CMJ) loss despite having similar values in squat, oxygen consumption, lactate after RSA test and CMJ height. Issue that could be attributed to the characteristics of the sport. This suggests that the volume should be increased oriented ability to perform repeated sprint actions over other type of training aimed at improving aerobic capacity especially at professional level.peerReviewe
Performance study of synthetic AER generation on CPUs for Real-Time Video based on Spikes
Address-Event-Representation (AER) is a neuromorphic interchip communication protocol that allows for real-time virtual massive connectivity between huge number neurons located on different chips. When building multi-chip muti-layered AER systems it is absolutely necessary to have a computer interface that allows (a) to read AER interchip traffic into the computer and visualize it on screen, and (b) convert conventional frame-based video stream in the computer into AER and inject it at some point of the AER structure. This is necessary for test and debugging of complex AER systems. Previous work presented several software methods for converting digital frames into AER format. Those methods were not feasible for real-time conversion those days because the processor performance was insufficient. Nowadays, Multi-core processor architectures and cache hierarchies have evolved and the performance is much better than Pentium 4 Mobile of those years. In this paper we study frame-to-AER methods for realtime video applications (40ms per frame) using modern processor architectures, compilers, and processors oriented for stand-alone applications (mini-PC processors
AER Building Blocks for Multi-Layer Multi-Chip Neuromorphic Vision Systems
A 5-layer neuromorphic vision processor whose components
communicate spike events asychronously using the address-eventrepresentation
(AER) is demonstrated. The system includes a retina
chip, two convolution chips, a 2D winner-take-all chip, a delay line
chip, a learning classifier chip, and a set of PCBs for computer
interfacing and address space remappings. The components use a
mixture of analog and digital computation and will learn to classify
trajectories of a moving object. A complete experimental setup and
measurements results are shown.Unión Europea IST-2001-34124 (CAVIAR)Ministerio de Ciencia y Tecnología TIC-2003-08164-C0
Presentación. Conociendo otros saberes: aportaciones a los estudios afroamericanos desde Centroamérica y el Caribe
The multidisciplinary angle with which FILHA Journal opens its pages in each biannual publication, gave the possibility of launching an extremely fruitful, albeit complex at times, international collaboration exercise, managing to include in this issue writings by academics and academics from different latitudes and various areas of knowledge of Latin American Social Sciences and Humanities.El ángulo multidisciplinario con que la Revista FILHA abre sus páginas en cada publicación semestral, dio la posibilidad de poner en marcha un ejercicio de colaboración internacional sumamente fructífero, aunque complejo por momentos, logrando incluir en el presente número escritos de académicas y académicos de distintas latitudes y diversas áreas del conocimiento de las Ciencias Sociales y las Humanidades latinoamericanas
Exploring the socio-ecological factors behind the (in)active lifestyles of Spanish post-bariatric surgery patients
Purpose: Physical activity (PA) is considered essential for the treatment of morbid obesity and the optimization of bariatric surgery outcomes. The objective of this article was to identify the facilitators and barriers that bariatric patients perceived to do PA one year after finishing a PA programme for the promotion of a long-term active lifestyle. This objective was addressed from a socio-ecological and qualitative perspective.
Methods: Nine patients (eight women and one man), aged between 31 and 59 years, participated in semi-structured interviews directly following the PA programme and one year after it. A content analysis was carried out to analyze the qualitative data.
Results: Weight loss, improvement of physical fitness, perceived competence, and enjoyment were the main facilitators of PA. Complexes related to skin folds, osteoarthritis, perceived unfavourable weather conditions, lack of social support and economic resources, long workdays, lack of specific PA programmes, and other passive leisure preferences were the main barriers to participate in PA.
Conclusions: Results highlight the important interplay between personal, social environmental, and physical environmental factors to explain (in)active behaviours of bariatric patients. The findings of this article could be useful for future research and interventions aimed at promoting PA in bariatric patients
Activity-Dependent Reconnection of Adult-Born Dentate Granule Cells in a Mouse Model of Frontotemporal Dementia
Frontotemporal dementia (FTD) is characterized by neuronal loss in the frontal and temporal lobes of the brain. Here, we provide the first evidence of striking morphological alterations in dentate granule cells (DGCs) of FTD patients and in a mouse model of the disease, Tau VLW mice. Taking advantage of the fact that the hippocampal dentate gyrus (DG) gives rise to newborn DGCs throughout the lifetime in rodents, we used RGB retroviruses to study the temporary course of these alterations in newborn DGCs of female Tau VLW mice. In addition, retroviruses that encode either PSD95:GFP or Syn:GFP revealed striking alterations in the afferent and efferent connectivity of newborn Tau VLW DGCs, and monosynaptic retrograde rabies virus tracing showed that these cells are disconnected from distal brain regions and local sources of excitatory innervation. However, the same cells exhibited a predominance of local inhibitory innervation. Accordingly, the expression of presynaptic and postsynaptic markers of inhibitory synapses was markedly increased in the DG of Tau VLW mice and FTD patients. Moreover, an increased number of neuropeptide Y-positive interneurons in the DG correlated with a reduced number of activated egr-1 + DGCs in Tau VLW mice. Finally, we tested the therapeutic potential of environmental enrichment and chemoactivation to reverse these alterations in mice. Both strategies reversed the morphological alterations of newborn DGCs and partially restored their connectivity in a mouse model of the disease. Moreover, our data point to remarkable morphological similarities between the DGCs of Tau VLW mice and FTD patients.Fil: Terreros Roncal, Julia. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Flor García, Miguel. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Moreno Jiménez, Elena P.. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Pallas Bazarra, Noemí. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Rábano, Alberto. No especifíca;Fil: Sah, Nirnath. National Institutes of Health; Estados UnidosFil: Van Praag, Henriette. National Institutes of Health; Estados UnidosFil: Giacomini, Damiana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Schinder, Alejandro Fabián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Ávila, Jesús. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Llorens Martín, Maria. Universidad Autónoma de Madrid. Facultad de Ciencias; Españ
Clutter Suppression for Indoor Self-Localization Systems by Iteratively Reweighted Low-Rank Plus Sparse Recovery
Self-localization based on passive RFID-based has many potential applications. One of the main challenges it faces is the suppression of the reflected signals from unwanted objects (i.e., clutter). Typically, the clutter echoes are much stronger than the backscattered signals of the passive tag landmarks used in such scenarios. Therefore, successful tag detection can be very challenging. We consider two types of tags, namely low-Q and high-Q tags. The high-Q tag features a sparse frequency response, whereas the low-Q tag presents a broad frequency response. Further, the clutter usually showcases a short-lived response. In this work, we propose an iterative algorithm based on a low-rank plus sparse recovery approach (RPCA) to mitigate clutter and retrieve the landmark response. In addition to that, we compare the proposed approach with the well-known time-gating technique. It turns out that RPCA outperforms significantly time-gating for low-Q tags, achieving clutter suppression and tag identification when clutter encroaches on the time-gating window span, whereas it also increases the backscattered power at resonance by approximately 12 dB at 80 cm for high-Q tags. Altogether, RPCA seems a promising approach to improve the identification of passive indoor self-localization tag landmarks
MOOC as a Way of Dissemination, Training and Learning of Telecommunication Engineering
In this chapter, the use of massive open online courses (MOOCs) for the dissemination, training capabilities and learning of telecommunication engineering is described taking as example the successful MOOC ‘Ultra- Dense Networks for 5G and its Evolution’ developed under the European innovative training network (ITN) TeamUp5G. MOOCs are usually understood as a way of teaching or learning for massive potential students. Indeed, this is the main goal of any MOOC. However, we also propose its use for training and dissemination. The ITN TeamUp5G is a training network for 15 PhD students of seven different institutions (universities and companies) where the students make research on different interconnected topics for the common goal of Ultra dense networks for 5G. At the same time they researched, they prepared a MOOC to disseminate their most recent advances and their challenges. For the MOOC, they needed to collect their thoughts, organizse their knowledge and establish a common vision of the whole system. The cooperative work, the cross-related meetings and, the preparation of all the materials for the MOOC were very interesting and useful in their training process. The whole experience of designing and creating the MOOC is described in detail along with the challenges and lessons learned.info:eu-repo/semantics/acceptedVersio
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