Multi-Output Kernel Adaptive Filtering Algorithms

RESUMEN: El aprendizaje supervisado tradicional es una herramienta de gran utilidad capaz de ayudar a la hora de tomar decisiones rápidas y precisas en tareas de regresión y predicción. El objetivo de este tipo de aprendizaje es aprender una función que mapee desde el espacio de instancias de entrada al espacio de salida, donde la salida puede ser una etiqueta o un valor escalar. No obstante, la complejidad creciente de las tareas y los problemas hacen necesaria la creación de nuevos modelos de Machine Learning que realicen una toma de decisiones más sofisticada, de tal forma que sean capaces de resolver varios problemas de este tipo al mismo tiempo, lo que se conoce con el nombre de Multitask Learning. Por ello, este proyecto se centrará en el desarrollo de nuevos modelos de Multitask Learning y, más concretamente, de algoritmos de filtrado adaptativo kernel de tipo Multi-Output, que consigan aprovechar la correlación existente entre las distintas series temporales para mejorar los resultados obtenidos. Además, se pretende que su complejidad sea mucho menor que la de otros modelos desarrollados hasta el momento, como pueden ser los procesos Gaussianos (GPs). Para evaluar las prestaciones de los métodos propuestos, se utiliza en primer lugar una base de datos generados mediante simulación, sobre la que se tiene un cierto control de sus parámetros, para realizar un completo análisis de las prestaciones de todos los algoritmos desarrollados y, a continuación, se seleccionan aquellos dos que han presentado unas mejores prestaciones para su aplicación sobre una base de datos real. Los resultados obtenidos para todos los algoritmos desarrollados son bastante buenos, destacando especialmente los de las versiones Multi-Output del KLMS con limitación del tamaño del diccionario mediante el empleo del criterio de distancia Euclídea (QKLMS-MO) y con aproximaciones de dimensiones finitas de las funciones kernel empleadas (RFF-KLMS-MO). Estos dos algoritmos obtienen unos resultados considerablemente buenos en términos del error cuadrático medio (del orden de 10-1), resultando bastante mejor el RFF-KLMS-MO en términos de complejidad computacional y tiempo empleado en el entrenamiento.ABSTRACT: Traditional supervised learning is a very useful tool that helps in making fast and accurate decisions for regression and prediction tasks. The main goal of this type of learning is to learn a function that maps from the input feature space to the output space, where the output is either a single label or a single value. However, the increasing complexity of tasks and problems urges the need of new Machine Learning models that have more sophisticated decision making mechanisms so they can solve several problems simultaneously, which is known as Multitask Learning. Thus, this project will focus on the development of new Multitask Learning models and, more precisely, of multi-output kernel adaptive-ltering algorithms, that take advantage of the existing correlation between time series to improve their results. Besides, its computational complexity is intended to be much lower than that of other models that have been developed up to now, such as Gaussian Processes (GPs). In order to evaluate their performance, a simulated and parameter-controlled dataset is first used to carry out a complete analysis of all algorithms capabilities. Then, a real dataset is used to evaluate the performance of the two bestperforming algorithms. The results obtained for all algorithms are valid, especially those obtained by the Multi-Output versions of the KLMS with dictionary size limitations based on the Euclidean distance criterion (QKLMS-MO) and with-nite-dimensional approximations of the kernel functions (RFF-KLMS-MO). These two algorithms provide very good results in terms of mean squared error (around 10-1), proving RFF-KLMS-MO to be a better choice in terms of computational complexity and training time.Máster en Ingeniería de Telecomunicació

Multi-output kernel adaptive filtering with reduced complexity

In this paper, two new multi-output kernel adaptive filtering algorithms are developed that exploit the temporal and spatial correlations among the input-output multivariate time series. They are multi-output versions of the popular kernel least mean squares (KLMS) algorithm with two different sparsification criteria. The first one, denoted as MO-QKLMS, uses the coherence criterion in order to limit the dictionary size. The second one, denoted as MO-RFF-KLMS, uses random Fourier features (RFF) to approximate the kernel functions by linear inner products. Simulation results with synthetic and real data are presented to assess convergence speed, steady-state performance and complexities of the proposed algorithms.This work was supported by the Ministerio de Ciencia, Innovación y Universidades and AEI/FEDER funds of the E.U., under grant PID2019-104958RB-C43 (ADELE)

History of the technical evolution of pressurized water nuclear reactors

El complejo sistema técnico que forma un reactor nuclear es un interesante caso desde la perspectiva de los Estudios Sociales de la Ciencia y la Tecnología. Dentro de las diferentes variantes que han sido diseñadas a lo largo de la historia, la variante pressurized water reactor (pwr) ha sido la más implantada alrededor del mundo. Para acometer el estudio de su evolución técnica se desarrolla una perspectiva «combinada» de los enfoques utilizados tradicionalmente en la Historia y la Sociología de la Tecnología: (i) el determinismo tecnológico, para estudiar la evolución autónoma de la tecnología en su etapa de desarrollo (en la década de los cincuenta); (ii) el constructivismo social, para una etapa posterior de influencia social (en la década de los setenta); y (iii) el enfoque de sistemas, en una etapa de transición entre las dos anteriores, para analizar factores políticos, económicos y también para abrir la caja negra del diseño pwr./n The complex technical system forming a nuclear reactor is an interesting case from the perspective of Studies Science, Technology and Society. Among the different variants that were designed along the history, the most implemented variant has been the pressurized water reactor (pwr). To undertake the study of its technical evolution, an evolutionary perspective approach is developed within the History and Sociology of Technology: (i) the technological determinism, to study the autonomous evolution of technology in its development stage (in the fifties); (ii) the social constructivism, to study the later stage of social influence (in the seventies); and (iii) the systems approach, in a stage of transition between the two previous stages, to analyze political and economic factors, as well as to open the black box of pwr design

Union bound minimization approach for designing grassmannian constellations

In this paper, we propose an algorithm for designing unstructured Grassmannian constellations for noncoherent multiple-input multiple-output (MIMO) communications over Rayleigh block-fading channels. Unlike the majority of existing unitary space-time or Grassmannian constellations, which are typically designed to maximize the minimum distance between codewords, in this work we employ the asymptotic pairwise error probability (PEP) union bound (UB) of the constellation as the design criterion. In addition, the proposed criterion allows the design of MIMO Grassmannian constellations specifically optimized for a given number of receiving antennas. A rigorous derivation of the gradient of the asymptotic UB on a Cartesian product of Grassmann manifolds, is the main technical ingredient of the proposed gradient descent algorithm. A simple modification of the proposed cost function, which weighs each pairwise error term in the UB according to the Hamming distance between the binary labels assigned to the respective codewords, allows us to jointly solve the constellation design and the bit labeling problem. Our simulation results show that the constellations designed with the proposed method outperform other structured and unstructured Grassmannian designs in terms of symbol error rate (SER) and bit error rate (BER), for a wide range of scenarios.This work was supported by Huawei Technologies, Sweden under the project GRASSCOM. The work of D. Cuevas was also partly supported under grant FPU20/03563 funded by Ministerio de Universidades (MIU), Spain. The work of Carlos Beltr´an was also partly supported under grant PID2020-113887GB-I00 funded by MCIN/ AEI /10.13039/501100011033. The work of I. Santamaria was also partly supported under grant PID2019-104958RB-C43 (ADELE) funded by MCIN/ AEI /10.13039/501100011033

A measure preserving mapping for structured Grassmannian constellations in SIMO channels

In this paper, we propose a new structured Grassmannian constellation for noncoherent communications over single-input multiple-output (SIMO) Rayleigh block-fading channels. The constellation, which we call Grass-Lattice, is based on a measure preserving mapping from the unit hypercube to the Grassmannian of lines. The constellation structure allows for on-the-fly symbol generation, low-complexity decoding, and simple bit-to-symbol Gray coding. Simulation results show that Grass-Lattice has symbol error rate performance close to that of a numerically optimized unstructured constellation, and is more power efficient than other structured constellations proposed in the literature.This work was supported by Huawei Technologies Sweden, under the project GRASSCOM. The work of D. Cuevas was also partly supported under grant FPU20/03563 funded by Ministerio de Universidades (MIU), Spain. The work of Carlos Beltr´an was also partly supported under grant PID2020-113887GB-I00 funded by MCIN/AEI /10.13039/501100011033. The work ofI. Santamaria was also partly supported under grant PID2019-104958RB-C43(ADELE) funded by MCIN/ AEI /10.13039/501100011033

SEM-EDX study of bentonite alteration under the influence of cement alkaline solutions

Bentonite is a key barrier for the isolation of high-level radioactive waste within Deep Geological Repository. However, bentonite may be altered by contact with cementitious materials and their alkaline pore fluids. This study offers an extensive morphological and semi-quantitative characterization of the bentonite surface exposed to three types of alkaline pore fluids released by different cement-based materials. The bentonite surfaces were studied using a thorough scanning electron microscopy exploration and analysed using an energy-dispersive ꭕ-ray detector (SEM-EDX). In addition, statistical, element mappings, ꭕ-ray diffraction and infrared spectroscopy analyses were performed. The aim was to have a picture of the morphological and chemical alterations of bentonite at very early stages in accordance with the integrated approach necessary to address bentonite stability in the long-term. As a consequence of the reactivity, two types of morphologies stood out in the matrix of bentonite: platelets and coatings-like crusts characterized by their high Mg and Ca content. These alterations presented a different scope depending on the type of alkaline pore solution involved and suggested the precipitation of authigenic magnesium silicate hydrates (M-S-H) and/or trioctahedral clay minerals and Ca‑carbonates. The knowledge of the performance of bentonite subjected to these alkaline solutions can help in the evaluation of the most suitable cement-based materials to be used next to bentoniteThe experimental work was supported by funding from the European Union‘s Horizon 2020 Research and Training programme from EURATOM [H2020-NFRP 2014, 2015] under grant agreement n◦662147; CEBAM

The yeast prefoldin-like URI-orthologue Bud27 associates with the RSC nucleosome remodeler and modulates transcription

Bud27, the yeast orthologue of human URI/RMP, is a member of the prefoldin-like family of ATPindependent molecular chaperones. It has recently been shown to mediate the assembly of the three RNA polymerases in an Rpb5-dependent manner. In this work, we present evidence of Bud27 modulating RNA pol II transcription elongation. We show that Bud27 associates with RNA pol II phosphorylated forms (CTD-Ser5P and CTD-Ser2P), and that its absence affects RNA pol II occupancy of transcribed genes. We also reveal that Bud27 associatesin vivo with the Sth1 component of the chromatin remodeling complex RSC and mediates its association with RNA pol II. Our data suggest that Bud27, in addition of contributing to Rpb5 folding within the RNA polymerases, also participates in the correct assembly of other chromatin-associated protein complexes, such as RSC, thereby modulating their activit

Renovación metodológica de la asignatura "Experimentación en ingeniería química" por incorporación del simulador comercial de procesos químicos Hysys. Simulación de prácticas de laboratorio y resultados docentes

[SPA]Las Tecnologías de la Información y la Comunicación (TIC) están promoviendo el uso de nuevas fórmulas de enseñanza y aprendizaje en el seno de la Universidad. En este sentido, los laboratorios virtuales pueden ser usados como complemento de las metodologías tradicionales de trabajo. Esta comunicación describe el uso del simulador comercial Hysys para el desarrollo de cinco sesiones de laboratorio virtuales en el área de Ingeniería Química. El progama permitió la simulación de tres importantes operaciones unitarias (destilación, extracción líquido-líquido e intercambio de calor) proporcionando un camino atractivo para introducir a los estudiantes en el análisis e interpretación de los resultados de laboratorio. La efectividad del proyecto de innovación fue evaluada a través de cuestionarios, y los resultados mostraron que, en promedio, más del 85% de los estudiantes consideraron Hysys de gran utilidad. [ENG]Information and Communication Technologies (ICT) are promoting the use of new teaching and learning styles in the University. Virtual labs can be adopted as a complement of the traditional laboratory methodologies. This communication describes the use of the commercial simulator Hysys in the implementation of five virtual labs for chemical engineering education. The program allowed the simulation of three important unit operations (distillation, liquid-liquid extraction and heat exchange) and it provided an attractive way to introduce students to the analysis and interpretation of the lab results. The effectiveness of the innovation project was evaluated through questionnaries and the results showed that, in average, more of 85% of the students considered Hysys of great utility in the classroom.Campus Mare Nostrum, Universidad Politécnica de Cartagena, Universidad de Murcia, Región de Murci

Effect of the aniline fragment in Pt(II) and Pt(IV) complexes as anti-proliferative agents. Standard reduction potential as a more reliable parameter for Pt(IV) compounds than peak reduction potential

The problems of resistance and side effects associated with cisplatin and other chemotherapeutic drugs have boosted research aimed at finding new compounds with improved properties. The use of platinum(IV) prodrugs is one alternative, although there is some controversy regarding the predictive ability of the peak reduction potentials. In the work described here a series of fourteen chloride Pt(II) and Pt(IV) compounds was synthesised and fully characterised. The compounds contain different bidentate arylazole heterocyclic ligands. Their cytotoxic properties against human lung carcinoma (A549), human breast carcinoma (MCF7) and human colon carcinoma (HCT116 and HT29) cell lines were studied. A clear relationship between the type of ligand and the anti-proliferative properties was found, with the best results obtained for the Pt(II) compound that contains an aniline fragment, (13), thus evidencing a positive effect of the NH2 group. Stability and aquation studies in DMSO, DMF and DMSO/water mixtures were carried out on the active complexes and an in-depth analysis of the two aquation processes, including DFT analysis, of 13 was undertaken. It was verified that DNA was the target and that cell death occurred by apoptosis in the case of 13. Furthermore, the cytotoxic derivatives did not exhibit haemolytic activity. The reduction of the Pt(IV) compounds whose Pt(II) congeners were active was studied by several techniques. It was concluded that the peak reduction potential was not useful to predict the ability for reduction. However, a correlation between the cytotoxic activity and the standard reduction potential was found.This work has been funded by the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU), Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) (RTI2018-100709-B-C21 to BRM, RTI2018-100709-B-C22 to AM, RTI2018-094093-B-I00 to RSP), Junta de Comunidades de Castilla-La Mancha-FEDER (JCCM) (grant SBPLY/19/180501/000260 to BRM), Ministerio de Economía y Competitividad (Project PID2019-104381GB-I00 to GC), Fundación Leticia Castillejo Castillo to MJRH, Junta de Castilla y León, Consejería de Educación y Cultura y Fondo Social Europeo (Projects BU263P18 and BU087G19 to JVC) as well as UCLM-FEDER (grants 2019-GRIN-27183 and 2019-GRIN-27209 to BRM) and University of Girona (MPCUdG2016/076 to AM)