Antón Civit
University of Seville
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Publication
Featured researches published by Antón Civit.
ubiquitous computing | 2001
Julio Abascal; Antón Civit
The rise of mobile telephony has opened a vast diversity of new opportunities for older people with different levels of physical restrictions due to ageing. Mobile technology allows not only ubiquitous communications but also anytime access to some services that are vital for elderly peoples security and autonomy. Nevertheless, with the numerous advantages, remote services can also introduce important social and ethical risks for this group of users. This paper tries to analyse the novelties that mobile technology may introduce into the lives of older users, points out some dangers and challenges arising from the use of these technologies and revises some future applications of the present mobile technologies.
international symposium on circuits and systems | 2006
Francisco Gomez-Rodriguez; R. Paz; Alejandro Linares-Barranco; Manuel Rivas; L. Miro; S. Vicente; Gabriel Jiménez; Antón Civit
Address-event-representation (AER) is a communications protocol for transferring spikes between bio-inspired chips. Such systems may consist of a hierarchical structure with several chips that transmit spikes among them in real time, while performing some processing. To develop and test AER based systems it is convenient to have a set of instruments that would allow to: generate AER streams, monitor the output produced by neural chips and modify the spike stream produced by an emitting chip to adapt it to the requirements of the receiving elements. In this paper we present a set of tools that implement these functions developed in the CAVIAR EU project
international conference on artificial neural networks | 2005
R. Paz; Francisco Gomez-Rodriguez; M. A. Rodriguez; Alejandro Linares-Barranco; Gabriel Jiménez; Antón Civit
Address-Event-Representation (AER) is a communication protocol for transferring spikes between bio-inspired chips. Such systems may consist of a hierarchical structure with several chips that transmit spikes among them in real time, while performing some processing. To develop and test AER based systems it is convenient to have a set of instruments that would allow to: generate AER streams, monitor the output produced by neural chips and modify the spike stream produced by an emitting chip to adapt it to the requirements of the receiving elements. In this paper we present a set of tools that implement these functions developed in the CAVIAR EU project.
international conference on artificial neural networks | 2005
Francisco Gomez-Rodriguez; R. Paz; L. Miro; Alejandro Linares-Barranco; Gabriel Jiménez; Antón Civit
Address-Event-Representation (AER) is a communications protocol for transferring images between chips, originally developed for bio-inspired image processing systems. In [6], [5] various software methods for synthetic AER generation were presented. But in neuro-inspired research field, hardware methods are needed to generate AER from laptop computers. In this paper two real time implementations of the exhaustive method, proposed in [6], [5], are presented. These implementations can transmit, through AER bus, images stored in a computer using USB-AER board developed by our RTCAR group for the CAVIAR EU project.
Neurocomputing | 2007
Alejandro Linares-Barranco; Matthias Oster; D. Cascado; Gabriel Jiménez; Antón Civit; Bernabé Linares-Barranco
Address-Event-Representation (AER) is a communication protocol for transferring images between chips, originally developed for bio-inspired image-processing systems. Such systems may consist of a complicated hierarchical structure with many chips that transmit images among them in real time, while performing some processing (for example, convolutions). In developing AER-based systems it is very convenient to have available some means of generating AER streams from on-computer stored images. Rank order coding (ROC) and Poisson rate coding are the extremes of spikes coding. In this paper, we present a pseudo-random hardware method for generating AER streams in real time from a sequence of images stored in a computers memory. The Kolmogorov-Smirnov test has been applied to quantify that this method follows a Poisson distribution of the spikes. A USB-AER board, developed by our RTCAR group, have been used for the measurements. An example scenario of use under the EU CAVIAR project is presented.
international symposium on circuits and systems | 2010
Alejandro Linares-Barranco; Rafael Paz-Vicente; Francisco Gomez-Rodriguez; A. Jiménez; Manuel Rivas; Gabriel Jiménez; Antón Civit
Image convolution operations in digital computer systems are usually very expensive operations in terms of resource consumption (processor resources and processing time) for an efficient Real-Time application. In these scenarios the visual information is divided into frames and each one has to be completely processed before the next frame arrives in order to warranty the real-time. A spike-based philosophy for computing convolutions based on the neuro-inspired Address-Event-Representation (AER) is achieving high performances. In this paper we present two FPGA implementations of AER-based convolution processors for relatively small Xilinx FPGAs (Spartan-II 200 and Spartan-3 400), which process 64×64 images with 11×11 convolution kernels. The maximum equivalent operation rate that can be reached is 163.51 MOPS for 11×11 kernels, in a Xilinx Spartan 3 400 FPGA with a 50MHz clock. Formulations, hardware architecture, operation examples and performance comparison with frame-based convolution processors are presented and discussed.
international symposium on circuits and systems | 2006
Rafael Paz-Vicente; Alejandro Linares-Barranco; D. Cascado; M. A. Rodriguez; Gabriel Jiménez; Antón Civit; José Luis Sevillano
Address event representation (AER) is a neuromorphic interchip communication protocol that allows for real-time connectivity between huge number neurons located on different chips. By exploiting high speed digital communication circuits (nano-seconds), synaptic neural connections can be time multiplexed (mili-seconds). 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; and (b) inject a sequence of events to the AER structure. This paper presents a PCI to AER interface, that dispatches a sequence of events with timing information. It is able to recovery the possible delays introduced by AER bus. It has been implemented in real time hardware using VHDL and tested in a PCI-AER board, developed by authors, that currently capable to send and receive events at a peak rate of 16 Mev/sec, and a typical rate of 10 Mev/sec
international symposium on circuits and systems | 2008
Angel Jiménez-Fernandez; Rafael Paz-Vicente; Manuel Rivas; Alejandro Linares-Barranco; Gabriel Jiménez; Antón Civit
Address-event-representation (AER) is an asynchronous protocol for transferring the information of spiking neuro-inspired systems. Actually AER systems are able to see, to ear, to process information, and to learn. Regarding to the actuation step, the AER has been used for implementing central pattern generator algorithms, but not for controlling the actuators in a closed-loop spike-based way. In this paper we analyze an AER based model for a real-time neuro-inspired closed-loop control system. We demonstrate it into a differential control system for a two-wheel vehicle using feedback AER information. PFM modulation has been used to power the DC motors of the vehicle and translation into AER of encoder information is also presented for the close-loop. A codesign platform (called AER-Robot), based into a Xilinx Spartan 3 FPGA and an 8051 USB microcontroller, with power stages for four DC motors has been used for the demonstrator.
international symposium on neural networks | 2010
A. Jimenez Fernandez; Alejandro Linares-Barranco; Rafael Paz-Vicente; Gabriel Jiménez; Antón Civit
Neuromorphic engineers study models and implementations of systems that mimic neurons behavior in the brain. Neuro-inspired systems commonly use spikes to represent information. This representation has several advantages: its robustness to noise thanks to repetition, its continuous and analog information representation using digital pulses, its capacity of pre-processing during transmission time, …, Furthermore, spikes is an efficient way, found by nature, to codify, transmit and process information. In this paper we propose, design, and analyze neuro-inspired building blocks that can perform spike-based analog filters used in signal processing. We present a VHDL implementation for FPGA. Presented building blocks take advantages of the spike rate coded representation to perform a massively parallel processing without complex hardware units, like floating point arithmetic units, or a large memory. Those low requirements of hardware allow the integration of a high number of blocks inside a FPGA, allowing to process fully in parallel several spikes coded signals.
international conference on electronics, circuits, and systems | 2008
Angel Jiménez-Fernandez; Alejandro Linares-Barranco; Rafael Paz-Vicente; Carlos Lujan-Martinez; Gabriel Jiménez; Antón Civit
Address-event representation (AER) is a neuromorphic communication protocol for transferring information of spiking neurons implemented into VLSI chips. These neuro-inspired implementations have been used to design sensor chips (retina, cochleas), processing chips (convolutions, filters) and learning chips, what makes possible the development of complex, multilayer, multichip neuromorphic systems. In biology one of the last steps of the processing is to move a muscle, to apply the results of these complex neuromorphic processing to the real world. One interesting question is to be able to transform, or translate, the AER information into robot movements, like for example, moving a DC motor. This paper presents several ways to translate AER spikes into DC motor power, and to control a DC motor speed, based on Pulse Frequency Modulation. These methods have been simulated into Simulink with Xilinx system generator, and tested into the AER-Robot platform.