Visual Spike-based Convolution Processing with a Cellular Automata Architecture

this paper presents a first approach for implementations which fuse the Address-Event-Representation (AER) processing with the Cellular Automata using FPGA and AER-tools. This new strategy applies spike-based convolution filters inspired by Cellular Automata for AER vision processing. Spike-based systems are neuro-inspired circuits implementations traditionally used for sensory systems or sensor signal processing. AER is a neuromorphic communication protocol for transferring asynchronous events between VLSI spike-based chips. These neuro-inspired implementations allow developing complex, multilayer, multichip neuromorphic systems and have been used to design sensor chips, such as retinas and cochlea, processing chips, e.g. filters, and learning chips. Furthermore, Cellular Automata is a bio-inspired processing model for problem solving. This approach divides the processing synchronous cells which change their states at the same time in order to get the solution.Ministerio de Educación y Ciencia TEC2006-11730-C03-02Ministerio de Ciencia e Innovación TEC2009-10639-C04-02Junta de Andalucía P06-TIC-0141

EL CONTENIDO CURRICULAR COMO ESTRATEGIA DE CONTENCION DE ALUMNOS DE 1º AÑO DE LA CARRERA DE ARQUITECTURA. FAUD.UNC.

El ingreso a la Universidad implica una inflexión en la vida y en la formación del estudiante. Es una etapa crítica del proceso de crecimiento y maduración, que debería generar un mayor grado de autonomía y autogestión. Los alumnos ingresantes en Arquitectura, presentan un grado importante de dispersión en cuanto a los contenidos curriculares aprendidos en el nivel medio y una gran disparidad de habilidades y hábitos de trabajo adquiridos en las etapas formativas previas. El curso de nivelación intenta paliar algunos de estas debilidades, pero es necesario que las asignaturas de primer año asuman en forma conjunta el objetivo nivelador para evitar la frustración de un grupo importante de estudiantes que fracasa en esta etapa. En los últimos años se detecta, además, una importante deserción de estudiantes al promediar el primer año. La propuesta pedagógica debe proveer alternativas para afrontar el escenario de un ingreso masivo, con condiciones infraestructurales deficitarias y una relación docente - alumno que dista mucho de ser óptima. Las asignaturas de los ciclos básicos universitarios son mediadoras en el proceso de aprendizaje que produce el paso de la escuela media a los estudios superiores y por lo tanto desempeñan un papel fundamental. Deben aportar instrumentos formativos acerca de los roles profesionales, de las posibilidades y alcances de la formación disciplinar y del contexto social y cultural de inserción. Nuestra Cátedra propone la implementación de un conjunto de estrategias de abordaje que permitan superar algunas de las disfunciones detectadas, potenciar las fortalezas y aprovechar las oportunidades, a través de una visión histórico-crítica de los ambientes humanos que, creemos, puede posibilitar la comprensión de los procesos de desarrollo profesional, y no solamente proveer información acerca de obras, autores o escenario

A Report on New Antennas for Satellite Communications on-the-move in Ka-band

This project was initiated in 2017 within the framework of the Spanish national research program, funded by the ministry of economics, industry and competitiveness. The scope of this project is focused on the design of ground terminals for the new generation of high-throughput satellites operating in the Ka band (from 19 to 31 GHz

Comments on “Ka-Band Coplanar Magic-T Based on Gap Waveguide Technology”

In the title paper, the author proposes a Ka-Band Coplanar Magic-T Based on Gap-Waveguide (GW) Technology. The major novelty claimed in the paper is the combination of ridge-gap and E-plane groove-gap waveguides for Ka-band applications. However, such combination of these two types of waveguides in GW technology was firstly proposed in 2017. This combination allows for the realization of numerous devices, and distribution networks in the millimeter-wave band. This comment aims to properly frame the evolution of the use of RGW-GGW networks and how their use can be useful for new mm-wave band devices. While the author’s Magic-T introduces a new feature by using a 4-port network, it is clear that the concept relies on previous ideas not mentioned in the manuscript and this can lead to confusion about its actual novel contributions. In addition, we intend to give the microwave community a proper perspective of the above work’s frame of reference

Polyamines as Quality Control Metabolites Operating at the Post-Transcriptional Level

[EN] Plant polyamines (PAs) have been assigned a large number of physiological functions with unknown molecular mechanisms in many cases. Among the most abundant and studied polyamines, two of them, namely spermidine (Spd) and thermospermine (Tspm), share some molecular functions related to quality control pathways for tightly regulated mRNAs at the level of translation. In this review, we focus on the roles of Tspm and Spd to facilitate the translation of mRNAs containing upstream ORFs (uORFs), premature stop codons, and ribosome stalling sequences that may block translation, thus preventing their degradation by quality control mechanisms such as the nonsense-mediated decay pathway and possible interactions with other mRNA quality surveillance pathways.A.F. was funded by the Spanish Ministry of Science, Innovation and Universities, grant number BIO2015-70483-R, and B.B.-P. was funded by the Generalitat Valenciana grant, VALi+d GVA APOSTD/2017/039. 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60-GHz Single-Layer Slot-Array Antenna fed by Groove Gap Waveguide

[EN] A V-band single-layer low-loss slot-array antenna is presented in this letter. Radiating slots are backed by coaxial cavities, which are fed through a groove gap waveguide E-plane corporate feed network. Cavity resonances are created by shortening nails with respect to the surrounding ones. This fact enables a compact single-layer architecture since coaxial cavities and feeding network can share the same bed of nails. A 16 x 16 array is designed, constructed, and measured to demonstrate the viability of this concept for high-gain single-layer slot-array antennas. In addition, this solution can be extended to circular polarization by seamlessly adding a polarizer above the slots without changing the feeding network piece. Measurements show a relative bandwidth of 10% with input reflection coefficient better than -10 dB and a mean antenna efficiency above 70% within the operating frequency band (57-66 GHz).This work was supported by the Spanish Ministry of Economy and Competitiveness under Project TEC2016-79700-C2-1-R.Ferrando-Rocher, M.; Valero-Nogueira, A.; Herranz Herruzo, JI.; Teniente, J. (2019). 60-GHz Single-Layer Slot-Array Antenna fed by Groove Gap Waveguide. IEEE Antennas and Wireless Propagation Letters. 18(5):846-850. https://doi.org/10.1109/LAWP.2019.2903475S84685018

Low-Sidelobe Flat Panel Array Fed by a 3D-Printed Half-Mode Gap Waveguide Amplitude-Tapering Network

[EN] This article presents the design and evaluation of an 8 x 8 Ka-band low-sidelobe slot array antenna using gap waveguide technology. The slot array is fed by a single-layer amplitude-tapering network implemented in half-mode groove gap waveguide, resulting in a low-profile, low-sidelobe antenna. The simplicity of the proposed feeding network, composed of a novel design of asymmetrical dividers, enables precise fabrication using cost-effective additive techniques. Experimental results demonstrate a significant reduction in sidelobe levels compared to traditional uniform arrays, with a radiation efficiency exceeding 84%. This design, featuring simple and robust asymmetrical splitters, is well-suited for applications requiring high gain and low interference.This work was supported in part by MCIN/AEI/10.13039/501100011033, and in part by ERDF A Way of Making Europe under Project PID2019-107688RB-C22 and Project PID2022-141055NB-C21.Castellá-Montoro, A.; Ferrando-Rocher, M.; Herranz Herruzo, JI.; Valero-Nogueira, A. (2024). Low-Sidelobe Flat Panel Array Fed by a 3D-Printed Half-Mode Gap Waveguide Amplitude-Tapering Network. IEEE Access. 12:2607-2614. https://doi.org/10.1109/ACCESS.2023.3347222260726141

A Novel Circularly-Polarized T-shaped Slot Array Antenna in Ka-band

[EN] A T-shaped slot-array antenna fed through a Groove Gap Waveguide (GGW) is presented in this paper. The array antenna operates at 30 GHz. The way the slots are excited, along with the T-shape on its lid allows a compact single-layer architecture. A uniform linear array of 12 elements is designed to demonstrate the viability of this concept for high-efficient singlelayer slot-array antennas. Preliminary results show a frequency bandwidth of 1 GHz with input reflection coefficient better than ¿12 dB. In addition, being a full-metal antenna, the expected efficiency is high. It is worth stressing the good polarization purity achieved, being below 1.5 dB within the band of interest.This work has been supported by the Spanish Ministry of Science, Innovation and Universities (Ministerio de Ciencia, Innovacion y Universidades) under project TEC2016-79700-C2-1-R.Ferrando-Rocher, M.; Herranz Herruzo, JI.; Sánchez-Escuderos, D.; Valero-Nogueira, A. (2020). A Novel Circularly-Polarized T-shaped Slot Array Antenna in Ka-band. IEEE. 1-3. https://doi.org/10.23919/EuCAP48036.2020.9135490S1

Dual Circularly-Polarized Slot-Array Antenna in Ka-Band fed by Groove Gap Waveguide

[EN] A dual circularly-polarized slot-array antenna fed by a Groove Gap Waveguide (GGW) and operating in the KaBand is presented in this paper. A simple mechanism is proposed to switch the polarization, from RHCP to LHCP, and viceversa. The lid of the antenna has two pieces: one fixed and one sliding. The fixed piece hosts T-shaped slots, and the sliding block is in charge of adjusting the offset of the perpendicular grooves with respect to the longitudinal slots. Preliminary results show an axial ratio below 1.5 dB for both, RHCP and LHCP, within a bandwidth of 1 GHz centered at 30 GHz.This work has been supported by the Spanish Ministry of Science, Innovation and Universities (Ministerio de Ciencia, Innovacion y Universidades) under project TEC2016-79700-C2-1-R.Ferrando-Rocher, M.; Herranz Herruzo, JI.; Sánchez-Escuderos, D.; Valero-Nogueira, A. (2020). Dual Circularly-Polarized Slot-Array Antenna in Ka-Band fed by Groove Gap Waveguide. IEEE. 421-422. https://doi.org/10.1109/IEEECONF35879.2020.9329473S42142

True-Time-Delay Mechanical Phase Shifter in Gap Waveguide Technology for Slotted Waveguide Arrays in Ka-band

This paper proposes a novel all-metal mechanical phase shifter in gap waveguide technology. The phase shifter is aimed at providing beam-scanning capabilities to conventional slot array antennas along the elevation plane. To validate experimentally the beam-steering functionality, a 4×8 slot-array antenna has been designed and fabricated, along with the phase-shifting mechanism. The whole antenna consists of two pieces: a lower rotatable block, which changes the length of concentric Groove Gap Waveguides, and an upper fixed block, where the slot-array antenna is placed. Experimental results validate the proposed concept, having obtained steering angles of up to 25∘, with gain levels around 20 dBi with an antenna efficiency close to 90%. A reflection coefficient below –10 dB is achieved for a wide range of rotation angles from 29.5 GHz to 30.5 GHz. The proposed phase shifter is completely scalable to any array size and its true-time-delay nature enables wide steering ranges for closely-spaced slot arrays with wideband radiation performance.This work was supported by the Spanish Ministry of Economics and competitiveness under project TEC2016-79700-C2-1-R