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Propuesta metodológica para la creación, adaptación y disolución de sesgos en los sistemas de organización del conocimiento
Get PDFLa organización del conocimiento, como área del saber, tiene como objetivo el generar representaciones del conocimiento para poder ser organizadas y posteriormente recuperadas. La construcción de estas representaciones debe realizarse tomando en cuenta la comunidad a la que va dirigida. Construir representaciones tomando en consideración la forma de percibir el mundo que tiene una determinada comunidad, ayuda a que estos puedan hacer uso de las colecciones de forma fácil e intuitiva. Sin embargo, y principalmente a consecuencia de la heterogeneidad de las comunidades, es muy complejo generar representaciones que satisfagan las necesidades de todos los grupos. El sesgo, por su parte, es una cualidad que contienen estas representaciones, y que, de forma voluntaria o no, se transforman en un vehículo de aspectos ideológicos, culturales, étnicos, políticos, escuelas teóricas, entre otros tantos. Un sesgo bien empleado es un elemento que puede servir para adaptar una representación a las necesidades de una comunidad. Sin embargo, un sesgo mal generado, puede ocasionar no solo la pérdida de información, a raíz de que los usuarios no logran encontrar la información bajo la denominación o el lugar asignado, sino que también puede mostrar ideas prejuiciosas o arcaicas sobre determinados tópicos. En esta investigación se proponen pautas metodológicas específicas en función de las tres perspectivas de sesgo trabajadas, según su ideología, según su presentación y según el tipo de representación. Estos cambios se presentan en dos grupos, por un lado, los cambios masivos en las estructuras de los sistemas de organización del conocimiento y por otro, los cambios menores en los sistemas. A modo de conclusión y a partir de los objetivos propuestos y la metodología planteada se pudo evaluar distintos enfoques metodológicos para la creación y actualización de los sesgos en las estructuras de los sistemas de organización del conocimiento. Esto permitió identificar estrategias necesarias para la generación de sesgos. Así como también responder a las preguntas de investigación planteadas.Knowledge organization aims to generate representations of knowledge so that they can be organized and subsequently retrieved. The construction of these representations should take into account the community for which they are intended. Creating representations that consider how a particular community perceives the world helps ensure that users can easily and intuitively use the collections. However, due to the heterogeneity of communities, it is very complex to generate representations that meet the needs of all groups. Bias, in turn, is a quality inherent in these representations, which, whether intentionally or not, becomes a vehicle for ideological, cultural, ethnic, political, or theoretical aspects, among others. Well-applied bias can serve as a tool to adapt a representation to the needs of a community. However, poorly generated bias can result not only in the loss of information, as users may fail to find information under the assigned term or location, but it can also perpetuate prejudiced or outdated ideas about certain topics. This research proposes specific methodological guidelines based on three perspectives of bias: according to its ideology, its presentation, and the type of representation. These changes are presented in two groups: on one hand, massive changes to the structures of knowledge organization systems, and on the other, minor changes to the systems. In conclusion, based on the proposed objectives and the methodology outlined, different methodological approaches for the creation and updating of biases in the structures of knowledge organization systems were evaluated. This allowed for the identification of necessary strategies for the generation of biases, as well as addressing the research questions posed.Programa de Doctorado en Documentación: Archivos y Bibliotecas en el Entorno Digital por la Universidad Carlos III de MadridPresidente: Isidora Gil Leiva.- Secretario: Daniel Martínez Ávila.- Vocal: Ana María Muñoz Muño
Detecting sparse cointegration
Get PDFWe propose a two-step procedure to detect cointegration in high-dimensional settings, focusing on sparse relationships. First, we use the adaptive LASSO to identify the small subset of integrated covariates driving the equilibrium relationship with a target series, ensuring model-selection consistency. Second, we adopt an information-theoretic model choice criterion to distinguish between stationarity and nonstationarity in the resulting residuals, avoiding dependence on asymptotic distributional assumptions. Monte Carlo experiments confirm robust finite-sample performance, even under endogeneity and serial correlation.Jesus Gonzalo gratefully acknowledges financial support from the Spanish Ministerio de Ciencia e Innovacion: PID2019-104960GB-I00; TED2021-129784B-I00; CEX2021-001181-M and Spanish Ministerio de Ciencia, Innovacion y Universidades: PID2023-147593NB-I00, financed by MICIU/AEI /10.13039/501100011033. Jean-Yves Pitarakis gratefully acknowledges financial support from the UK Economic and Social Research Council through grant ES/W000989/1
Exploring eye-movement changes as digital biomarkers and endophenotypes in subclinical eating disorders: an eye tracking study
No full textObjective
Previous research has indicated that patients with Anorexia Nervosa (AN) exhibit specific eye movement changes, identified through eye tracking sensor technology. These changes have been proposed as potential digital biomarkers and endophenotypes for early diagnosis and preventive clinical interventions. This study aims to explore whether these eye movement changes are also present in individuals with subclinical eating disorder (ED) symptomatology compared to control participants.
Method
The study recruited participants using convenience sampling and employed the Eating Disorder Examination Questionnaire for initial screening. The sample was subsequently divided into two groups: individuals exhibiting subclinical ED symptomatology and control participants. Both groups performed various tasks, including a fixation task, prosaccade/antisaccade task, and memory-guided task. Alongside these tasks, anxiety and premorbid intelligence were measured as potential confounding variables. The data were analyzed through means comparison and exploratory Pearson"s correlations.
Results
No significant differences were found between the two groups in the three eye tracking tasks.
Discussion
The findings suggest that the observed changes in previous research might be more related to the clinical state of the illness rather than a putative trait. Implications for the applicability of eye movement changes as early biomarkers and endophenotypes for EDs in subclinical populations are discussed. Further research is needed to validate these findings and understand their implications for preventive diagnostics.This publication is supported by the project grant “MAGIC outFIT” I + D + i / PID2019-105579RB-I00 funded by the Spanish Agencia Estatal de Investigación MCIN/AEI/https://doi.org/10.13039/501100011033/, where ATJ and MSM are the Principal Investigators; the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement nr 101002711; project BODYinTRANSIT, where ATJ is Principal Investigator). SNL was supported by the FPU program from the Spanish Ministerio de Educación, Cultura y Deporte (FPU20/00089). LDC acknowledges support from the CONEX‑Plus programme funded by Universidad Carlos III de Madrid and the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska‑Curie grant agreement No. 801538
RF Challenge: The Data-Driven Radio Frequency Signal Separation Challenge
Get PDFWe address the critical problem of interference rejection in radio-frequency (RF) signals using a data-driven approach that leverages deep-learning methods. A primary contribution of this paper is the introduction of the RF Challenge, which is a publicly available, diverse RF signal dataset for data-driven analyses of RF signal problems. Specifically, we adopt a simplified signal model for developing and analyzing interference rejection algorithms. For this signal model, we introduce a set of carefully chosen deep learning architectures, incorporating key domain-informed modifications alongside traditional benchmark solutions to establish baseline performance metrics for this intricate, ubiquitous problem. Through extensive simulations involving eight different signal mixture types, we demonstrate the superior performance (in some cases, by two orders of magnitude) of architectures such as UNet and WaveNet over traditional methods like matched filtering and linear minimum mean square error estimation. Our findings suggest that the data-driven approach can yield scalable solutions, in the sense that the same architectures may be similarly trained and deployed for different types of signals. Moreover, these findings further corroborate the promising potential of deep learning algorithms for enhancing communication systems, particularly via interference mitigation. This work also includes results from an open competition based on the RF Challenge, hosted at the 2024 IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP’24).This work was supported in part by the United States Air Force Research Laboratory and the United States Air Force Artificial Intelligence Accelerator under Cooperative Agreement under Grant FA8750-19-2-1000, and in part by the National Science Foundation (NSF) under Grant CCF-2131115. The work of Alejandro Lancho was supported in part by the Comunidad de Madrid’s 2023 Cesar Nombela program under Grant 2023-T1/COM-29065; in part by the Comunidad de Madrid under Grant TEC-2024/COM-89; and in part by the Ministerio de Ciencia, Innovación y Universidades, Spain, under Grant PID2023-148856OA-I00
In situ synthesis of biocompatible NaY1−xGdxF4 :Yb/Er nanoparticles for cell labeling and temperature sensing
No full textBiocompatible, up-converting NaY1-xGdxF4:Yb/Er nanoparticles have been successfully obtained in situ by chitosan assisted solvothermal synthesis, and were further characterized to check their potential for optical thermometry. The temperature dependent change in the green emission intensity, originating from the thermalization between 4S3/2 and 2H11/2 levels, implied maximum relative sensitivity of 1.3 %K-1 in the physiologically interesting temperature range. Presence of chitosan ligands at the nanoparticles surface promotes their biocompatibility. The nanoparticles concentration ranging from 10 to 50 µg/mL yielded viability higher than 80 % for HS-5 fibroblast and SCC-25 oral cancer cells. Efficient visualization of alfaNaY0.65Gd0.15F4:Yb0.18Er0.02 nanoparticles in cytoplasmic region of cells, under excitation at 976 nm, validates their potential to be used for cell labeling and temperature sensing in tissue.The research was supported by the Ministry of Science, Technological Development and Innovation of the Republic of Serbia on the research programs of Institute of Physics Belgrade and Institute of Technical Sciences of SASA (Grant No. 451-03-136/2025-03/200175)
Harnessing Orbital Energy with Bare Tape-Like Electrodynamic Tethers for Efficient Space Debris Mitigation
Get PDFProceedings of: 9th European Conference on Space Debris, 1-4 april 2025. Bonn (Germany)Electrodynamic tethers (EDTs) have a unique attribute that distinguishes them from any other in-orbit propulsion technology: they can convert orbital energy into electrical energy as they deorbit space debris from Low Earth Orbit. The harvested energy can be used immediately or stored to be utilized later. This study explores energy-repurposing cases with the goal of incentivizing space sustainability and opening new market opportunities. The work starts by integrating DISCOS and Spacetrack databases. The combined database is then filtered to identify the most promising scenarios in terms of object removal effectiveness, taking into account the orbits addressable by EDTs and the total harvestable energy. A simulation of such scenarios, which involve orbits with a 35◦ inclination and objects weighing 300–500 kg, shows that a 1–2-km-long EDT can deorbit from an 800-km altitude within a few months, generating tens to hundreds of watts continuously during the deorbiting process.This work was supported by the European Union’s Horizon Europe Research and Innovation Programme (No 101161603, E.T.COMPACT project)
Technology Progress and In-orbit Demonstration of Electrodynamic Tethers in the framework of the E.T.PACK Initiative
Get PDFProceedings of: 9th European Conference on Space Debris, 1 April 2025 - 4 April 2025, Bonn, GermanyThe results of the qualification campaign of the engineering qualification model of a 12 U and 20 kg deorbit device based on electrodynamic tether (EDT) technology are presented. The campaign included pressure, leak, functional, partial tether deployment, vibration, shock, thermal vacuum cycling, electromagnetic compatibility, module separation, and full tether deployment tests. The flight model of the deorbit device is currently under development and will pass the acceptance test campaign in Q3 2025. The flight of the DD, planned in an orbit of 49◦ of inclination and about 550 km of altitude, is scheduled in Q2 2026.This work was supported by the European Union’s Horizon Europe Research and Innovation Programme (No 101058166, E.T.PACK-F project)
InP/Si3N4 Hybrid Integrated Lasers for RF Local Oscillator Signal Generation in Satellite Payloads
Get PDFThis paper presents an integrated tunable hybrid multi-laser module designed to simultaneously generate multiple radiofrequency (RF) local oscillator (LO) signals through optical heterodyning. The device consists of five hybrid InP/Si3N4 integrated lasers, each incorporating an intracavity wavelength-selective optical filter formed by two micro-ring resonators. Through beating the wavelengths generated from three of these lasers, we demonstrate the simultaneous generation of two LO signals within bands crucial for satellite communications (SatCom): one in the Ka-band and the other in the V-band. The device provides an extensive wavelength tuning range across the entire C-band and exhibits exceptionally narrow optical linewidths, below 40 kHz in free-running mode. This results in ultra-wideband tunable RF signals with narrow electrical linewidths below 100 kHz. The system is compact and highly scalable, with the potential to generate up to 10 simultaneous LO signals, being a promising solution for advanced RF signal generation in high throughput satellite payloads.This work has been supported by the European Space Agency through the TRP program “Tuneable Photonic RF Demultiplexer for Broadband Satellites—THORMUX” (GA 870421), by the European Union through the projects TERA6G (GA 101096949), SPRINTER (GA 101070581), and POLYNICES (G.A. 101070549), and by a Spanish national project, “6G-Xtreme” (Ref. TSI-063000-2021-136)
Innovative cases on working time reduction and flexible working time arrangements in Europe
Get PDFThe book is the result of the European InnovaWorking (Innovative and flexible approaches to working time, no. 101126491) project that was coordinated by the Universidad Carlos III of Madrid with funding from the European Union.
We are very thankful to have received the support of an excellent scientific committee made up of the European Trade Union Institute (Aude Cefaliello), the European Trade Union Confederation (Giovanni Casale and Joakim Smedman), the University of Valencia (Adrián Todolí) and the VU-Amsterdam (Klara Boonstra).
We also appreciate the support provided by the Fundación 1º de Mayo (CCOO), UGT, CEOE and PRLInnovación in conducting the interviews with the social agents within the framework of the project.Contiene: Is there a future for working time in the digital age? / Jesús R. Mercader Uguina (pp. 5-16). -- Innovative cases on working time reduction and flexible working time arrangements: findings of the InnovaWorking project / Ana Belén Muñoz Ruiz, Francisco Javier Gómez Abelleira and Pablo Gimeno Díaz de Atauri (pp. 17-49). -- Case study on Finland: examples of innovative working time arrangements in the inflexible low-wage sectors / Aino Salmi, Garima Singh, Minna van Gerven and Satu Ojala (pp. 50-72). -- Case study on France: pioneers of Woking Time Reduction / Nuria Ramos Martín (pp. 73-102). -- Case study on Hungary: employer-driven working time innovation within institutional constraints / Sára Hungler (pp. 103-122). -- Case study on Ireland: bargaining for flexible work in Higher Education and Banking / Dagmar Schiek and Mary Naughton (pp. 123-142). -- Case study on the Netherlands: flexible working time arrangements / Nuria Ramos Martín (pp. 143-171). -- Case study on Spain: company-level initiatives on working time reduction across sectors / Francisco Javier Gómez Abelleira, Pablo Gimeno Díazde Atauri and Ana Belén Muñoz Ruiz (pp. 172-192)
La Antigüedad grecorromana como modelo e instrumento de modernización y transformación cultural en España y Latinoamérica
Get PDFEste libro trata de explicar, a través de distintas vías, cómo la Antigüedad
grecorromana se convirtió en un instrumento de modernización y
transformación cultural en España y en los países de Latinoamérica. Esta
idea modernizadora de la Antigüedad, asociada a conceptos como civilización,
orden y progreso, permitió una constante actualización de lo
«clásico», consolidándolo como un símbolo de prestigio y buen gusto
que es analizado a través de veinticuatro capítulos escritos por expertos
de siete países diferentes. Estos muestran el uso variado que la Antigüedad
ha tenido en un amplio marco cronológico y en un nutrido ámbito
temático que abarca la historiografía, la literatura, la prensa, la formación
académica, el arte, las colecciones, las artes escénicas, el viaje y la polític