Person:
Tirado Fernández, José Francisco

First Name

José Francisco

Last Name

Tirado Fernández

URI

https://hdl.handle.net/20.500.14352/75059

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Físicas

Department

Arquitectura de Computadores y Automática

Area

Arquitectura y Tecnología de Computadores

Identifiers

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Search Results

Now showing 1 - 10 of 27

2-D wavelet transform enhancement on general-purpose microprocessors: memory hierarchy and SIMD parallelism exploitation
(High performance computing - HIPC 2002, proceedings, 2002) Chaver Martínez, Daniel Ángel; Tenllado Van Der Reijden, Christian Tomás; Piñuel Moreno, Luis; Prieto Matías, Manuel; Tirado Fernández, José Francisco
This paper addresses the implementation of a 2-D Discrete Wavelet Transform on general-purpose microprocessors, focusing on both memory hierarchy and SIMD parallelization issues. Both topics are somewhat related, since SIMD extensions are only useful if the memory hierarchy is efficiently exploited. In this work, locality has been significantly improved by means of a novel approach called pipelined computation, which complements previous techniques based on loop tiling and non-linear layouts. As experimental platforms we have employed a Pentium-III (P-III) and a Pentium-4 (P-4) microprocessor. However, our SIMD-oriented tuning has been exclusively performed at source code level. Basically, we have reordered some loops and introduced some modifications that allow automatic vectorization. Taking into account the abstraction level at which the optimizations are carried out, the speedups obtained on the investigated platforms are quite satisfactory, even though further improvement can be obtained by dropping the level of abstraction (compiler intrinsics or assembly code).
Optimization of a Line detection algorithm for autonomous vehicles on a RISC-V with accelerator
(Journal of computer science & technology, 2022) Belda Beneyto, María José; Olcoz Herrero, Katzalin; Castro Rodríguez, Fernando; Tirado Fernández, José Francisco
In recent years, autonomous vehicles have attracted the attention of many research groups, both in academia and business, including researchers from leading companies such as Google, Uber and Tesla. This type of vehicles are equipped with systems that are subject to very strict requirements, essentially aimed at performing safe operations -both for potential passengers and pedestrians- as well as carrying out the processing needed for decision making in real time. In many instances, general-purpose processors alone cannot ensure that these safety, reliability and real-time requirements are met, so it is common to implement paper explores the acceleration of a line detection aprunning without accelerator.
Robust motion estimation on a low-power multi-core DSP
(Eurasip journal on advances in signal processing, 2013) Igual Peña, Francisco Daniel; Botella Juan, Guillermo; García Sánchez, Carlos; Prieto Matías, Manuel; Tirado Fernández, José Francisco
Medical imaging has become an absolutely essential diagnostic tool for clinical practices; at present, pathologies can be detected with an earliness never before known. Its use has not only been relegated to the field of radiology but also, increasingly, to computer-based imaging processes prior to surgery. Motion analysis, in particular, plays an important role in analyzing activities or behaviors of live objects in medicine. This short paper presents several low-cost hardware implementation approaches for the new generation of tablets and/or smartphones for estimating motion compensation and segmentation in medical images. These systems have been optimized for breast cancer diagnosis using magnetic resonance imaging technology with several advantages over traditional X-ray mammography, for example, obtaining patient information during a short period. This paper also addresses the challenge of offering a medical tool that runs on widespread portable devices, both on tablets and/or smartphones to aid in patient diagnostics.
Analysing value substitution and confidence estimation for value prediction
(Journal of systems architecture, 2001) Piñuel Moreno, Luis; Moreno-Vozmediano, Rafael; Tirado Fernández, José Francisco
Value Prediction is one of the newest techniques used to break down ILP limits. Despite being under continuous study during the last few years, a few aspects related to this emerging technique remain unanalysed in depth. Exhaustively investigated in the context of control speculation, confidence estimation has usually played a secondary role on value prediction and speculation. Closely linked to confidence estimation, value substitution also represents a relegated subject of research. This paper is focussed on analysing, in an isolated way, the respective impact on predictor performance of both confidence estimation and value substitution mechanisms. By using detailed pipeline-level simulations, we prove that improvements in these mechanisms are as important as reducing the predictor aliasing or even improving the prediction model.
Offset printing plate quality sensor on a low-cost processor
(Sensors, 2013) Poljak, Jelena; Botella Juan, Guillermo; García Sánchez, Carlos; Poljacek, Sanja Mahovic; Prieto Matías, Manuel; Tirado Fernández, José Francisco
The aim of this work is to develop a microprocessor-based sensor that measures the quality of the offset printing plate through the introduction of different image analysis applications. The main features of the presented system are the low cost, the low amount of power consumption, its modularity and easy integration with other industrial modules for printing plates, and its robustness against noise environments. For the sake of clarity, a viability analysis of previous software is presented through different strategies, based on dynamic histogram and Hough transform. This paper provides performance and scalability data compared with existing costly commercial devices. Furthermore, a general overview of quality control possibilities for printing plates is presented and could be useful to a system where such controls are regularly conducted.
Low complexity bit-parallel polynomial basis multipliers over binary fields for special irreducible pentanomials
(Integration, 2013) Imaña Pascual, José Luis; Hermida Correa, Román; Tirado Fernández, José Francisco
Finite field GF(2m) arithmetic is becoming increasingly important for a variety of different applications including cryptography, error coding theory and computer algebra. Among finite field arithmetic operations, GF(2m) multiplication is of special interest because it is considered the most important building block. GF(2m) multipliers present reduced space and time complexities when the field is generated by some special irreducible polynomials. Among these, irreducible pentanomials of degree m are specially important because they are abundant and there are several eligible candidates for a given m. In this paper, we consider bit-parallel polynomial basis multipliers over the finite field GF(2m) generated using type 2 irreducible pentanomials, for which explicit formulas and algorithms for the computation of the products are given. In this contribution, two new subclasses of type 2 irreducible pentanomials are also introduced. The theoretical complexity analysis proves that the bit-parallel multipliers here presented have the lowest number of XOR gates known to date for similar polynomial basis multipliers based on this type of irreducible pentanomials, while the number of AND gates and the time complexity match the best known results found in the literature.
CEPRAM: Compression for Endurance in PCM RAM
(Journal of circuits systems and computers, 2017) González Alberquilla, Rodrigo; Castro Rodríguez, Fernando; Piñuel Moreno, Luis; Tirado Fernández, José Francisco
We deal with the endurance problem of Phase Change Memories (PCM) by proposing Compression for Endurance in PCM RAM (CEPRAM), a technique to elongate the lifespan of PCM-based main memory through compression. We introduce a total of three compression schemes based on already existent schemes, but targeting compression for PCM-based systems. We do a two-level evaluation. First, we quantify the performance of the compression, in terms of compressed size, bit-flips and how they are affected by errors. Next, we simulate these parameters in a statistical simulator to study how they affect the endurance of the system. Our simulation results reveal that our technique, which is built on top of Error Correcting Pointers (ECP) but using a high-performance cache-oriented compression algorithm modified to better suit our purpose, manages to further extend the lifetime of the memory system. In particular, it guarantees that at least half of the physical pages are in usable condition for 25% longer than ECP, which is slightly more than 5% more than a scheme that can correct 16 failures per block.
Project number: 283
Aprendizaje Servicio e Innovación Social desde la Universidad
(2018) Carabantes Alarcón, David; Ancochea Soto, Eumenio; Arias Astray, Andrés; Dupont Sfez, Samuelle; Iglesias Recuero, Silvia; Manjón-Cabeza Olmeda, Araceli; Martín Martín, Óliver; Montero, Javier; Romero Ruiz del Portal, Francisco; San Andrés Moya, Margarita; Sastre Castillo, Miguel Ángel; Tirado Fernández, José Francisco
El Aprendizaje Servicio es una estrategia docente necesaria para el desarrollo de iniciativas de emprendimiento e innovación social, que partan desde la Universidad, y que se puedan incorporar en las diferentes áreas de conocimiento de la UCM
A low cost matching motion estimation sensor based on the NIOS II microprocessor.
(Sensors, 2012) González, Diego; Botella Juan, Guillermo; Meyer Baese, Uwe; García Sánchez, Carlos; Sanz, Concepción; Prieto Matías, Manuel; Tirado Fernández, José Francisco
Medical imaging has become an absolutely essential diagnostic tool for clinical practices; at present, pathologies can be detected with an earliness never before known. Its use has not only been relegated to the field of radiology but also, increasingly, to computer-based imaging processes prior to surgery. Motion analysis, in particular, plays an important role in analyzing activities or behaviors of live objects in medicine. This short paper presents several low-cost hardware implementation approaches for the new generation of tablets and/or smartphones for estimating motion compensation and segmentation in medical images. These systems have been optimized for breast cancer diagnosis using magnetic resonance imaging technology with several advantages over traditional X-ray mammography, for example, obtaining patient information during a short period. This paper also addresses the challenge of offering a medical tool that runs on widespread portable devices, both on tablets and/or smartphones to aid in patient diagnostics.
bioNMF: a web-based tool for nonnegative matrix factorization in biology
(Nucleic acids research, 2008) Mejia Roa, E.; Carmona Saez, P.; Nogales, R.; Vicente, C.; Vázquez, M.; Yang, X. Y.; García, C.; Tirado Fernández, José Francisco; Pascual Montano, Alberto
Medical imaging has become an absolutely essential diagnostic tool for clinical practices; at present, pathologies can be detected with an earliness never before known. Its use has not only been relegated to the field of radiology but also, increasingly, to computer-based imaging processes prior to surgery. Motion analysis, in particular, plays an important role in analyzing activities or behaviors of live objects in medicine. This short paper presents several low-cost hardware implementation approaches for the new generation of tablets and/or smartphones for estimating motion compensation and segmentation in medical images. These systems have been optimized for breast cancer diagnosis using magnetic resonance imaging technology with several advantages over traditional X-ray mammography, for example, obtaining patient information during a short period. This paper also addresses the challenge of offering a medical tool that runs on widespread portable devices, both on tablets and/or smartphones to aid in patient diagnostics.