1,935 research outputs found
Spike Processing on an Embedded Multi-task Computer: Image Reconstruction
There is an emerging philosophy, called Neuro-informatics, contained
in the Artificial Intelligence field, that aims to emulate how living beings do tasks
such as taking a decision based on the interpretation of an image by emulating spiking
neurons into VLSI designs and, therefore, trying to re-create the human brain at
its highest level. Address-Event-Representation (AER) is a communication protocol
that has embedded part of the processing. It is intended to transfer spikes between
bioinspired chips. An AER based system may consist of a hierarchical structure with
several chips that transmit spikes among them in real-time, while performing some
processing. There are several AER tools to help to develop and test AER based systems.
These tools require the use of a computer to allow the higher level processing of
the event information, reaching very high bandwidth at the AER communication level.
We propose the use of an embedded platform based on a multi-task operating system
to allow both, the AER communication and processing without the requirement of either
a laptop or a computer. In this paper, we present and study the performance of a
new philosophy of a frame-grabber AER tool based on a multi-task environment. This
embedded platform is based on the Intel XScale processor which is governed by an
embedded GNU/Linux system. We have connected and programmed it for processing
Address-Event information from a spiking generator.Ministerio de Educación y Ciencia TEC2006-11730-C03-0
Calibration process on the study of new antenna array architectures for space communications
This paper introduces novel calibration processes
applied to antenna arrays with new architectures and
technologies designed to improve the performance of traditional earth stations for satellite communications due to the increasing requirement of data capacity during last decades. Besides, the Radiation Group from the Technical University of Madrid has been working on the development of new antenna arrays based on novel architecture and technologies along many projects as a solution for the ground segment in the early future. Nowadays, the calibration process is an interesting and cutting edge
research field in a period of expansion with a lot of work to do for calibration in transmission and also for reception of these novel antennas under development
Calibration proposal for new antenna array architectures and technologies for space communications
In large antenna arrays with a large number of antenna elements, the required number of measurements for the characterization of the antenna array is very demanding in cost and time. This letter presents a new offline calibration process for active antenna arrays that reduces the number of measurements by subarray-level characterization. This letter embraces measurements, characterization, and calibration as a global procedure assessing about the most adequate calibration technique and computing of compensation matrices. The procedure has been fully validated with measurements of a 45-element triangular panel array designed for Low Earth Orbit (LEO) satellite tracking that compensates the degradation due to gain and phase imbalances and mutual coupling
Annual report on Sunspot Counting Program 2018
Este programa de observación nació a finales del año 2012 en la Universidad de Extremadura (Badajoz, 38°53′ N 6°58′ W) con el fin de ampliar aún más nuestra investigación en la reconstrucción de la actividad solar. Desde el 1 de Enero de 2013, nuestros recuentos de manchas solares se han presentado al Real Observatorio de Bélgica (ROB) como contribución a los esfuerzos internacionales de mantener y actualizar el número internacional de Manchas Solares. Para ello, hemos utilizado un pequeño refractor apocromático de 80 mm de diámetro de objetivo y 550 mm de longitud focal, a fin de proyectar una imagen de 150 mm de diámetro en una plantilla. Después se hace un dibujo para obtener el recuento de manchas solares. Además, se realizan observaciones solares desde una estación secundaria en Valencia de las Torres (38°24′ N 6°00′ W) con un refractor –70 mm de diámetro objetivo y 700 mm de distancia focal– cuando algunos días la estación principal (en Badajoz) falla.
Este informe proporciona un conjunto completo de los datos obtenidos durante el año 2018, con cuatro tablas que muestran nuestros datos. Por otra parte, el índice de referencia de las manchas solares se compara con nuestros resultados.
Esperamos que esta publicación sea de utilidad a la comunidad científica que estudia el número de manchas solares: la mayor serie de índices solares derivadas de la observación directa del Sol.This program was born in late 2012 at the University of Extremadura (Badajoz, 38°53′ N 6°58′ W) in order to further extend our research in the reconstruction of past solar activity (see, for example, Vaquero, 2007). Since 1st January 2013, our sunspot counts have been submitted to the Royal Observatory of Belgium (ROB) as a contribution to the international effort of maintaining and updating the International Sunspot Number. For this purpose, we use a small apochromatic refractor –80 mm of objective diameter and 550 mm of focal length– to project a 150 mm diameter image onto a template. Then, a drawing is done so we obtain our sunspot counts from it. Moreover, solar observations from a secondary station located in Valencia de las Torres (38°24′ N 6°00′ W) with a refractor –70 mm of objective diameter and 700 mm of focal length– are carried out some days when the main station (in Badajoz) fails.
In this report, we provide a complete set of data obtained throughout the year 2018, with four tables including our data. Moreover, the reference sunspot index is compared with our results.
We hope that this publication is useful to the scientific community studying the sunspot number: the longest solar index series derived from direct observation of the Sun.• Ministerio de Educación, Cultura y Deporte: Ayuda FPU / grant FPU. • Fondos FEDER-Junta de Extremadura: Ayuda al Grupo de Investigación GR18097 y Proyecto IB16127 / Research Group Grant GR18097 and project IB16127 • Ministerio de Economía y Competitividad of the Spanish Government proyecto CGL2017-87917-P / project CGL2017-87917-
Annual report on Sunspot Counting Program 2013
Este programa nació a fines del 2012 en la Universidad de Extremadura con el fin de ampliar aún más nuestra investigación en la reconstrucción de la actividad solar. Desde el 1 de Enero de 2013, nuestro recuento de manchas solares se han presentado al Real Observatorio de Bélgica (ROB) como contribución a los esfuerzos internacionales de mantener y actualizar el número internacional de Manchas Solares. Para ello, hemos utilizado un pequeño refractor apocromático de 80 mm de diámetro de objetivo y 550 mm de longitud focal, a fin de proyectar una imagen de 150 mm de diámetro en una plantilla.
Este informe proporciona un conjunto completo de los datos obtenidos durante el año 2013, con cuatro tablas que muestran nuestros datos. Por otra parte, el índice de referencia de las manchas solares se compara con nuestros resultados.
Esperamos que esta publicación sea de utilidad a la comunidad científica que estudia el número de manchas solares: la mayor serie de índices solares derivadas de la observación directa del Sol.This program was born in late 2012 at the University of Extremadura in order to further extend our research in the reconstruction of past solar activity. Since 1st January 2013, our sunspot counts have been submitted to the Royal Observatory of Belgium (ROB) as a contribution to the international effort of maintaining and updating the International Sunspot Number. For this purpose, we have used a small apochromatic refractor –80mm of objective diameter and 550mm of focal length– to project a 150mm diameter image onto a template.
In this report, we provide a complete set of data obtained throughout the year 2013, with four Tables showing our data. Moreover, the reference sunspot index is compared with our results.
We hope that this publication be useful to the scientific community studying the sunspot number: the longest solar index series derived from direct observation of the Sun
Annual report on Sunspot Counting Program 2013
Este programa nació a fines del 2012 en la Universidad de Extremadura con el fin de ampliar aún más nuestra investigación en la reconstrucción de la actividad solar. Desde el 1 de Enero de 2013, nuestro recuento de manchas solares se han presentado al Real Observatorio de Bélgica (ROB) como contribución a los esfuerzos internacionales de mantener y actualizar el número internacional de Manchas Solares. Para ello, hemos utilizado un pequeño refractor apocromático de 80 mm de diámetro de objetivo y 550 mm de longitud focal, a fin de proyectar una imagen de 150 mm de diámetro en una plantilla.
Este informe proporciona un conjunto completo de los datos obtenidos durante el año 2013, con cuatro tablas que muestran nuestros datos. Por otra parte, el índice de referencia de las manchas solares se compara con nuestros resultados.
Esperamos que esta publicación sea de utilidad a la comunidad científica que estudia el número de manchas solares: la mayor serie de índices solares derivadas de la observación directa del Sol.This program was born in late 2012 at the University of Extremadura in order to further extend our research in the reconstruction of past solar activity. Since 1st January 2013, our sunspot counts have been submitted to the Royal Observatory of Belgium (ROB) as a contribution to the international effort of maintaining and updating the International Sunspot Number. For this purpose, we have used a small apochromatic refractor –80mm of objective diameter and 550mm of focal length– to project a 150mm diameter image onto a template.
In this report, we provide a complete set of data obtained throughout the year 2013, with four Tables showing our data. Moreover, the reference sunspot index is compared with our results.
We hope that this publication be useful to the scientific community studying the sunspot number: the longest solar index series derived from direct observation of the Sun
New Conjugated Compound T5 Epidioxy-Sterol-ANB Inhibits the Growth of Mycobacterium tuberculosis Affecting the Cholesterol and Folate Pathways
ABSTRACT: The upsurge and persistence of drug resistant strains of Mycobacterium tuberculosis
(Mtb) is an important limitant to the battery of drugs available for the elimination of
tuberculosis (TB). To avoid future scarcity of antibiotics against Mtb, it is important to
discover new effective anti-mycobacterial agents. In this study, we present data from a
series of experiments to determine in vitro and in vivo anti-mycobacterial activity of a
library of epidioxy-sterol analogs. We test 15 compounds for their ability to reduce the
viability of Mtb. We found that one compound called T5 epidioxy-sterol-ANB display
significant potency against Mtb in vitro specifically inside macrophages but without
effectivity in axenic cultures. A viability assay confirms that this T5 compound is less
toxic for macrophages in vitro as compared to the current Mtb drug Rifampicin at higher
concentrations. We use a transcriptomic analysis of Mtb inside macrophages after T5
epidioxy-sterol-ANB treatment, and we found a significant down-regulation of enzymes
involved in the cholesterol and folic acid pathways. In vivo, significant differences were
found in the lungs and spleen CFUs of Mtb infected mice treated with the T5 epidioxysterol-ANB as compared with the untreated control group, which provides additional
evidence of the effectivity of the T5 compound. Altogether these results confirm the
potential of this T5 epidioxy-sterol-ANB compound against Mtb
Annual report on Sunspot Counting Program 2016
Este programa observación nació a finales del año 2012 en la Universidad de Extremadura con el fin de ampliar aún más nuestra investigación en la reconstrucción de la actividad solar. Desde el 1 de Enero de 2013, nuestros recuentos de manchas solares se han presentado al Real Observatorio de Bélgica (ROB) como contribución a los esfuerzos internacionales de mantener y actualizar el número internacional de Manchas Solares. Para ello, hemos utilizado un pequeño refractor apocromático de 80 mm de diámetro de objetivo y 550 mm de longitud focal, a fin de proyectar una imagen de 150 mm de diámetro en una plantilla.
Este informe proporciona un conjunto completo de los datos obtenidos durante el año 2016, con cuatro tablas que muestran nuestros datos. Por otra parte, el índice de referencia de las manchas solares se compara con nuestros resultados.
Esperamos que esta publicación sea de utilidad a la comunidad científica que estudia el número de manchas solares: la mayor serie de índices solares derivadas de la observación directa del Sol.This program was born in late 2012 at the University of Extremadura (Badajoz, 38°53′ N
6°58′ W) in order to further extend our research in the reconstruction of past solar activity
(see, for example, Vaquero, 2007). Since 1st January 2013, our sunspot counts have been
submitted to the Royal Observatory of Belgium (ROB) as a contribution to the
international effort of maintaining and updating the International Sunspot Number. For
this purpose, we use a small apochromatic refractor –80 mm of objective diameter and
550 mm of focal length– to project a 150 mm diameter image onto a template. Then, a
drawing is done so we obtain our sunspot counts from it.
In this report, we provide a complete set of data obtained throughout the year 2016, with
four Tables showing our data. Moreover, the reference sunspot index is compared with
our results.
We hope that this publication is useful to the scientific community studying the sunspot
number: the longest solar index series derived from direct observation of the Sun
Annual report on Sunspot Counting Program 2019
Este programa nació a finales de 2012 en la Universidad de Extremadura (Badajoz, 38 ° 53 ′ N 6 ° 58 ′ O) para ampliar aún más nuestra investigación en la reconstrucción de la actividad solar pasada (ver, por ejemplo, Vaquero, 2007) . Desde el 1 de enero de 2013, nuestros recuentos de manchas solares se han enviado al Observatorio Real de Bélgica (ROB) como una contribución al esfuerzo internacional de mantener y actualizar el número internacional de manchas solares. Para este propósito, usamos un pequeño refractor apocromático –80 mm de diámetro objetivo y 550 mm de distancia focal– para proyectar una imagen de 150 mm de diámetro en una plantilla. Luego, se realiza un dibujo para que podamos obtener nuestros recuentos de manchas solares. Además, las observaciones solares de estaciones secundarias se llevan a cabo algunos días cuando falla la estación principal (en Badajoz). Una de estas estaciones también está en Badajoz (en una parte diferente de la ciudad) y está equipada con un refractor –90 mm de diámetro objetivo y 910 mm de distancia focal–, y la otra está en Valencia de las Torres (38 ° 24 ′ N 6 ° 00 ′ W) y está equipado con un refractor más pequeño –70 mm de diámetro objetivo y 700 mm de distancia focal–. En este informe, proporcionamos un conjunto completo de datos obtenidos a lo largo del año 2019, con cuatro tablas que incluyen nuestros datos. Además, el índice de referencia del número de manchas solares se compara con nuestros resultados. Esperamos que esta publicación sea útil para la comunidad científica que estudia el número de manchas solares: la serie de índice solar más larga derivada de la observación directa del Sol.This program was born in late 2012 at the University of Extremadura (Badajoz, 38°53′ N 6°58′ W) in order to further extend our research in the reconstruction of past solar activity (see, for example, Vaquero, 2007). Since 1st January 2013, our sunspot counts have been submitted to the Royal Observatory of Belgium (ROB) as a contribution to the international effort of maintaining and updating the International Sunspot Number. For this purpose, we use a small apochromatic refractor –80 mm of objective diameter and 550 mm of focal length– to project a 150 mm diameter image onto a template. Then, a drawing is done so we obtain our sunspot counts from it. Moreover, solar observations from secondary stations are carried out some days when the main station (in Badajoz) fails. One of these stations is in Badajoz too (in a different part of the city) and is equipped with a refractor –90 mm of objective diameter and 910 mm of focal length–, and the other one is in Valencia de las Torres (38°24′ N 6°00′ W) and is equipped with a smaller refractor –70 mm of objective diameter and 700 mm of focal length–. In this report, we provide a complete set of data obtained throughout the year 2019, with four tables including our data. Moreover, the reference sunspot number index is compared with our results.
We hope that this publication is useful to the scientific community studying the sunspot number: the longest solar index series derived from direct observation of the Sun.• Fondos FEDER-Junta de Extremadura: Ayuda al Grupo de Investigación GR18097 y Proyecto IB16127
• Ministerio de Economía y Competitividad of the Spanish Government proyecto CGL2017-87917-P
• Agencia Estatal de Investigación (Ministerio de Ciencia, Innovación y Universidades) del Gobierno español: beca predoctoral PRE2018-08489
Progresos en sub-sistemas RF y control de la Antena Adaptativa Multihaz GEODA
GEODA project started in 2006 as a complex and ambitious project in the smart antenna field. GEODA is a multiple planar array smart antenna working at 1.7 GHz designed to receive and automatically track several LEO satellite signals simultaneously [1-4]. GEODA evolved to GEODA-GRUA since transmission capabilities were given to the original idea [5-6], so that radiofrequency sub-systems had to be re-designed and digital management subsystem modified accordingly. In this paper, improvements in the reception/transmission (T/R) modules as well as in the Control Subsystem are presented, keeping the original radiating element
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