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Magnetic Actuation for Mechanomedicine
No full textIn the perspective of this article, the emergence of materials and systems for magneto-mechanical actuation in the field of mechanobiology is presented, and their potential to promote and advance biomedical research is discussed. These materials, ranging from single particles to compliant 2D substrates to 3D scaffolds, enable mechanical modulation of cells in a remote, dynamic, and reversible fashion. These features represent a major advance enabling researchers to reproduce time-evolving physiological and pathological processes in vitro and transmit mechanical forces and deformations to activate cellular responses or promote directed cell migration. As smart in vitro platforms, magneto-responsive systems may accelerate the discovery of mechanically mediated cellular mechanisms as therapeutic targets. In addition, the low magnetic susceptibility of biological tissues may facilitate the translation of in vitro approaches to in vivo settings, opening new routes for biomedical applications.D.G.G. acknowledges support from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Program (grant agreement no. 947723, project: 4D-BIOMAP, and grant agreement no. 101081713, project: ISBIOMECH). R.R. acknowledges support from the NSF CAREER Award, the ARO ECP Award, and the ONR YIP Award. S.S. thanks the ETH Zurich Research Program. A.T. acknowledges the NUS Presidential Young Professorship, Ministry of Education Tier 1, and iHT OOE support
GENIE Learn: Human-Centered Generative AI-Enhanced Smart Learning Environments
No full textProceedings of the 17th International Conference on Computer Supported Education (CSEDU), April 1-3, 2025, Porto, PortugalThis paper presents the basis of the GENIE Learn project, a coordinated three-year research project funded by the Spanish Research Agency. The main goal of GENIE Learn is to improve Smart Learning Environments (SLEs) for Hybrid Learning (HL) support by integrating Generative Artificial Intelligence (GenAI) tools in a way that is aligned with the preferences and values of human stakeholders. This article focuses on analyzing the problems of this research context, as well as the affordances that GenAI can bring to solve these problems, but considering also the risks and challenges associated with the use of GenAI in education. The paper also details the objectives, methodology, and work plan, and expected contributions of the project in this context.This work was supported by grants PID2023-146692OB-C31, PID2023-146692OB-C32 and PID2023-146692OB-C33 funded by MICIU/AEI/10.13039/501100011033 and by ERDF/EU, Project GENIELearn. DHL (Serra Húnter) acknowledges support by ICREA Academia
Mechanical properties of two novel non-equiatomic Zr-Hf-Ti-Cu-Ni-Co-Al High Entropy Alloys with high glass forming ability
No full textThis manuscript aims to study the microstructure and mechanical properties of two novel non-equiatomic Zr27.5Hf11.1Ti6.2Cu32.4Ni10.7Co5.5Al6.6 and Zr29.7Hf16.8Ti5.2Cu6.3Ni12.1Co8.4Al21.5 at% High Entropy Alloys (HEAs) obtained at two different average cooling rates (~1000 K/s and ~250 K/s, for 2 and 4 mm diameter samples, respectively). For each casted sample, the cooling rate also changes with the distance from the centre (lowest) to the edge (fastest) thus enabling to explore the evolution of the microstructures at a wide range of cooling rates. For the Zr27.5Hf11.1Ti6.2Cu32.4Ni10.7Co5.5Al6.6 alloy, the mechanical properties variation between the highest and lowest cooled regions, from the narrow amorphous ring edge (nanoindentation hardness H = 8.2 ± 0.42 GPa) to the centre of the largest sample (H = 8.8 ± 0.35 GPa), is very small. This is attributed to the small microstructural differences, mostly formation of a solid solution BCC crystalline phase, although with some HCP phase. The amorphous phase is in a very relaxed state, about to crystallize. However, for the Zr29.7Hf16.8Ti5.2Cu6.3Ni12.1Co8.4Al21.5 alloy, larger microstructural differences, and therefore mechanical properties, between the highest and lowest cooled regions are detected. From a fully amorphous region far from equilibrium (H = 8.5 ± 0.44 GPa) to a solid solution of BCC (~80 % vol.) and HCP (~20 % vol.) crystalline phase (H = 10.8 ± 0.6 GPa) and free from brittle intermetallic phases. This suggests, the latter alloy is a nearer eutectic composition and therefore the microstructure is more sensitive to changes of the cooling rate, something to take into consideration when designing microstructures for engineering applications.Sergio González is grateful for the Royal Society International Exchanges grant IES\R3|223106 and to the Spanish Ministry of Science, Innovation and Universities for the financial support through the “Beatriz Galindo” Program (BG23/00159)
DiWi: A Transformer-Based Digital Twin for Wireless Mobility
No full textUnderstanding device mobility in wireless networks is essential for multiple purposes: optimizing space usage, managing intelligent buildings, or improving network efficiency. However, the use of real mobility data raises significant privacy concerns. In this work, we propose DiWi (a Digital twin for Wireless mobility), a Transformer-based model to generate spatiotemporal mobility traces that mimic real-life behavior while preserving user privacy. We validate the utility of DiWi by comparing real and synthetic datasets, and by demonstrating its usefulness in a series of use cases related to mobility management, resource consumption, and privacy enhancements. We also confirm that DiWi is secure by evaluating empirical privacy metrics, such as, direct leakage, similarity searches, or membership inference. Our results illustrate that DiWi serves to generate realistic and useful mobility patterns without exposing identifiable user traces, making it a valuable tool for privacy-preserving mobility analysis. Furthermore, we investigate how enforcing differential privacy affects the generative performance of the model.This article is part of the project 6GINSPIRE PID2022-137329OB-C42, funded by MCIN/AEI/10.13039/501100011033 and the TUCAN6-CM project (TEC-2024/COM-460), funded by CM (ORDEN 5696/2024). This work is also partly funded by the SNS JU under the European Union’s Horizon Europe research and innovation programme under Grant Agreement No 101139198, iTrust6G project
Static Output-Feedback Path-Tracking Controller Tolerant to Steering Actuator Faults for Distributed Driven Electric Vehicles
No full textThe steering system plays a critical role in the vehicle¿s handling and directly influences its lateral dynamics. Faults or abnormal behavior in this system can affect performance, cause vehicle instability, and even lead to accidents. Therefore, considering these potential events is essential for designing robust controllers for autonomous vehicles. For this reason, in this work, a fault-tolerant path-tracking Static Output-Feedback controller is designed to handle steering actuator faults in autonomous vehicle steering systems. The controller adopts a Linear Parameter Varying approach to effectively handle nonlinearities associated with varying vehicle speeds and tire behavior. Furthermore, it only uses information from sensors, avoiding estimation stages. This controller can operate in two modes: a no-fault mode where only the steering is controlled to follow the reference path and a fault mode where the controller manages both the steering and torque vectoring. In fault mode, torque vectoring compensates for faults in the steering actuator. The design of the controller is completed considering gain faults in the steering system. The simulation results show that the proposed controller successfully maintains vehicle stability and significantly reduces tracking errors during high-risk maneuvers, achieving reductions of up to 50.65% in lateral error and 47.26% in heading error under worst-case fault scenarios.The work was supported in part by the grant [PID2022-136468OB-I00] funded by MCIN/AEI/ 10.13039/501100011033 by “ERDF A way of making Europe”
Aprendizaje automático aplicado en redes eléctricas inteligentes, para incidencias de tecnologías de la información y de la infraestructura eléctrica
No full textUna red eléctrica inteligente conocida comúnmente como Smart Grid SG es un sistema ciber físico que utiliza tecnologías avanzadas de la información y de las comunicaciones Su propósito es monitorear y gestionar la transmisión y o distribución de electricidad de todas las fuentes de generación para satisfacer las demandas de los consumidores Esto requiere la coordinación de las necesidades y capacidades de generadores operadores usuarios finales organismos de control y otras organizaciones involucradas con la finalidad de operar todas las partes de la red de la manera más eficiente posible minimizando los costos e impactos ambientales y maximizando la fiabilidad resistencia y estabilidad del sistema eléctrico Los trabajos orientados a la resiliencia de este tipo de infraestructuras se apoyan cada vez más en el empleo de técnicas de inteligencia artificial Big Data e internet de las cosas con la finalidad de buscar soluciones eficientes para diversos escenarios de la operación en el suministro transporte o generación de energía
En este documento se estudia la aplicación de modelos de aprendizaje automático en las dos grandes perspectivas de las SG la informática y la infraestructura eléctrica Para ello se dispone de datos proporcionados por un operador real los cuales han sido etiquetados y anonimizados para evitar la identificación de la organización facilitadora El objetivo que se persigue es proponer metodologías aplicables a la SG presentar modelos de aprendizaje y evaluarlos
La literatura revisada sugiere una tendencia al estudio principalmente de la detección de anomalías y en menor medida a la predicción de fallos con un gran énfasis transversal en la ciber seguridad nuevas técnicas de aprendizaje y Big Data Abordando limitaciones como la disponibilidad de pocos datos tiempos cada vez más cortos en los que se requiere resultados o mayor conectividad con internet Hay una propensión a no depender de forma estricta de los modelos de red y generar soluciones híbridas combinando varios modelos de aprendizaje o técnicas de inteligencia artificial
Este trabajo de investigación emplea una metodología científica que se puede describir como una combinación cuantitativa y descriptiva es un enfoque mixto que integra elementos cualitativos Para el análisis de datos se empleó proceso estándar intersectorial para la minería de datos CRISP-DM El primer escenario es buscar modelos para predecir el número semanal de incidencias relacionadas a las tecnologías de la información de las comunicaciones como parte de servicios de soporte y mantenimiento del software de la SG El segundo escenario es la predicción del número de clientes o consumidores afectados a partir del conjunto de incidencias de interrupción del suministro de energía eléctrica registradas en un sistema OMS Se evalúan cinco modelos orientados a las series de tiempo y la regresión para aportar a las necesidades de predicción planteadas como objetivos
Finalmente se proponen las metodologías de gestión de predicción de incidencias de TIC GPITIC y gestión de predicciones de clientes afectados por dispositivo otra orientada a las interrupciones de servicio en la SG GPCADPrograma de Doctorado en Ciencia y Tecnología Informática por la Universidad Carlos III de MadridPresidenta: Ana María Iglesias Maqueda.- Secretario: Manuel Eugenio Morocho Cayamcela.- Vocal: Iván Danilo García Santillá
Cavity control of topological qubits: fusion rule, anyon braiding, and Majorana-Schrödinger cat states
No full textWe investigate the effects of coupling a local electromagnetic cavity to a segment of a topological Kitaev chain (KC), with particular emphasis on the interplay between photons and Majorana zero modes (MZMs). In addition to the well-known scissor effect-which effectively partitions the chain and isolates free MZMs in the bulk-we provide evidence of non-trivial fusion rules and braiding operations, hallmark signatures of non-Abelian anyons, enabled by spatially selective ultrastrong KC-cavity coupling. We propose that these distinctive MZM properties can be experimentally probed via fermionic parity measurements and photon-induced Berry phases. Furthermore, we demonstrate that, in the so-called sweet-spot regime, the coupled system can be mapped onto a Rabi-like model with a homodyne-rotated quadrature, offering a simplified yet powerful theoretical description. Exploiting the symmetry of fermionic modes within a two-site cavity configuration, we also show the feasibility of generating hybrid MZM-polariton Schrödinger cat states. Our findings offer a novel approach to manipulating topological quantum matter through local light–matter interactions and provide theoretical tools for future experimental realizations in platforms such as quantum materials or superconducting circuits.L.Q. and F.J.R. would like to thank Facultad de Ciencias-UniAndes projects: INV-2021-128-2292 and INV-2023-162-2833 for financial support and institutional support provided during the STAI research period. F.J.G-R and I.A.B-G acknowledge financial support from Spanish MCIN with funding from European Union Next Generation EU (PRTRC17.I1) and Consejería de Educación from Junta de Castilla y León through QCAYLE project. Additional support from the Department of Education, Junta de Castilla y Leon, and FEDER funds (CLU-2023-1-05) is also acknowledged. C.T. acknowledges financial support from the project ‘Nanofotonica para Computacion Cuantica’ (NanoQuCo) with reference Y2020/TCS-6545 of the Comunidad de Madrid (CAM)
Drift-gradient instabilities in a plasma with 2D gradient effects: Application to a magnetic nozzle
No full textInstabilities common to E x B partially magnetized plasmas can ultimately lead to anomalous electron cross-field transport. This work presents a local linear analysis of fluid instabilities driven by the electron E x B drift and gradients in the equilibrium magnitudes of an essentially collisionless plasma. Effects of magnetic curvature, finite electron Larmor radius, and 3D wave propagation are included. Expanding on previous works, the role of gradients both perpendicular and parallel to the magnetic field is analyzed. The analysis of the dispersion relation for the complex frequency of the modes shows that a generalization of the classical lower-hybrid drift instability (LHDI) develops when paral-lel gradients or parallel propagation are accounted for. Furthermore, this LHDI becomes a generalized modified two-stream instability when perpendicular gradients are absent. Weak collisionality can reduce or enhance the growth rate of the collisionless LHDI, depending on the parametric range of parallel effects. The application of the LHDI dispersion relation to the simulation data of a magnetic nozzle plasma at equilibrium highlights the importance of parallel inhomogeneities in the instability developing in certain nozzle regions. The qualitative agreement with available experimental data on magnetic nozzles is discussed, too. Finally, quasi-linear analysis suggests that the LHDI-induced cross-field transport in the outward direction acts to smooth out the zeroth-order drifts which cause the plasma to destabilize in the first place, and may be an essential mechanism partaking in electron detachment from a magnetic nozzle.This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Starting Grant project ZARATHUSTRA, grant agreement No. 950466). The participation of E. Ahedo lies within the R&D project PID2022-140035OB-I00 (HEEP) funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe.
Fundamentos de Ingeniería Eléctrica
No full textEste libro está dirigido a estudiantes de la asignatura Fundamentos de Ingeniería Eléctrica, impartida en el segundo curso de los Grados en Tecnologías Industriales, Ingeniería Eléctrica, Ingeniería Mecánica e Ingeniería Electrónica y Automática de la Universidad Carlos III de Madrid. Su contenido puede resultar útil también en otras titulaciones vinculadas con la electrotecnia y el análisis de circuitos eléctricos. El texto se organiza en cuatro capítulos. El primero presenta los elementos básicos de los circuitos eléctricos, sus propiedades, las relaciones entre tensión y corriente y el intercambio de potencia. El segundo aborda los métodos de resolución de circuitos en corriente continua incluyendo los equivalentes de Thevenin y Norton. El tercero se centra en los circuitos de corriente alterna sinusoidal en régimen permanente, justifica el uso de la corriente alterna en los sistemas eléctricos, analiza el papel de los transformadores y estudia la potencia en sistemas de corriente alterna. El cuarto introduce los sistemas trifásicos equilibrados, sus magnitudes características y el análisis de la potencia en estos sistemas. El libro incluye ejemplos resueltos paso a paso que pueden facilitar la comprensión de los contenidos teóricos
The fall of the Asad Dynasty in Syria: local, regional and global factors
Get PDFEste artículo explora los factores que llevaron al colapso del régimen de la dinastía Asad en Siria a finales de 2024. A través de un enfoque histórico-estructural y geopolítico, se analizan las dinámicas locales, regionales y globales que influyeron en el desarrollo del conflicto desde las protestas de 2011. El estudio destaca cómo la interacción de estos factores, incluidos los cambios internos, la retirada del apoyo de actores internacionales clave y el creciente peso de las fuerzas opositoras, favoreció la caída del régimen. Además, se examina la evolución de grupos armados como Hayat Tahrir al-Sham y cómo su relación con patrocinadores externos aceleró el desenlace. También se considera la transformación de las alianzas internacionales y regionales, que marcaron las políticas de apoyo y oposición al régimen. Este análisis proporciona una visión integral del fin de medio siglo de dictadura en Siria, subrayando la necesidad de comprender cómo las interacciones entre los distintos niveles fueron fundamentales en la desestabilización del poder.This article explores the factors that led to the collapse of the Asad dynasty regime in Syria by the end of 2024. Using a historical-structural and geopolitical approach, it examines the local, regional and global dynamics that influenced the course of the conflict since the protests of 2011. The study highlights how the interaction of these factors, including internal changes, the withdrawal of support from key international actors, and the growing strength of opposing forces, contributed to the regime’s downfall. Additionally, the evolution of armed groups like Hayat Tahrir al- Sham is analyzed, along with how their relationship with external sponsors accelerated the collapse. The transformation of international and regional alliances, which shaped policies of support and resistance to the regime, is also considered. This analysis provides a comprehensive view of the end of half a century of dictatorship in Syria, emphasizing the need to understand how the interactions between different levels were crucial in destabilizing the regime’s power