Artículos (Tecnología Electrónica)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/11417

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Gestión óptima en microrredes con soporte fotovoltaico e hidrógeno verde
(Comité Español de Automática, 2025) Moliner Heredia, Rubén; Vivas Venegas, Carlos; Rodríguez Rubio, Francisco; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Ingeniería de Sistemas y Automática; Agencia Estatal de Investigación. España
La gestión de la energía es esencial para un correcto control de una microrred. Es importante que dicha gestión tenga en cuenta la optimización de la vida útil de los componentes de la microrred. Uno de los posibles comportamientos que se desean evitar es el apagado y encendido continuo de determinados componentes, tales como las celdas de combustible y los electrolizadores. En este artículo se ha propuesto un algoritmo usando control predictivo basado en modelo (MPC) utilizando diversas restricciones de tiempos mínimos de activación de dichos componentes para evitar efectos perjudiciales sobre los equipos de hidrógeno verde. Además, se ha propuesto un método de transmisión entre iteraciones del algoritmo para que la aplicación de dichas restricciones sea compatible con errores en las predicciones del algoritmo y de perturbaciones en el sistema. Para validar el algoritmo propuesto, se ha desarrollado un modelo simplificado de la microrred, y se han realizado simulaciones y comparaciones con varios algoritmos utilizando Matlab.
Low-Cost Full Correlated-Power-Noise Generator to Counteract Side-Channel Attacks
(MDPI, 2025-03-12) Tena Sánchez, Erica; Potestad Ordóñez, Francisco Eugenio; Zúñiga González, Virginia; Acosta Jiménez, Antonio José; Universidad de Sevilla. Departamento de Tecnología Electrónica; Ministerio de Ciencia e Innovación (MICIN). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Junta de Andalucía; European Union (UE). H2020; Ministerio para la Transformacion Digital y Función Pública; European Commission. Fondo Social Europeo (FSO); Universidad de Sevilla. TIC180: Diseño de Circuitos Integrados Digitales y Mixtos
Considerable attention has been given to addressing side-channel attacks to improve the security of cryptographic hardware implementations. These attacks encourage the exploration of various countermeasures across different levels of abstraction, through masking and hiding techniques, mainly. In this paper, we introduce a novel hiding countermeasure designed to mitigate Correlation Power Analysis (CPA) attacks without significant overhead. The new countermeasure interferes with the processed data, minimizing the power correlation with the secret key. The proposed method involves using a Correlated-Power-Noise Generator (CPNG). This study is supported by experimental results using CPA attacks on a SAKURA-G board with a SPARTAN-6 Xilinx FPGA. An Advanced Encryption Standard (AES) cipher with 128/256-bit key size is employed for this purpose. The proposed secure design of AES has an area overhead of 29.04% compared to unprotected AES. After conducting a CPA attack, the acquisition of information about the private key has been reduced drastically by 44.5%.
Assessing the impact of vaccines on COVID-19 efficacy in survival rates: a survival analysis approach for clinical decision support
(Frontiers Media, 2024-11) González Rodríguez, Juan Luis; Oprescu, Andreea M.; Muñoz Lezcano, Sergio; Cordero Ramos, Jaime; Romero Cabrera, Juan Luis; Armengol de la Hoz, Miguel Ángel; Estella, Ángel; Universidad de Sevilla. Departamento de Tecnología Electrónica
Background: The global COVID-19 pandemic, caused by the SARS-CoV-2 virus, has presented significant challenges to healthcare systems worldwide. Objective: This study, based on an analysis of a cohort from the Public Health System of Andalusia (Spain), aims to evaluate how vaccination affects case-fatality rate in patients hospitalized due to COVID-19 infection in Andalusia. Methods: The cohort consists of 37,274 individuals after applying the inclusion criteria. We conducted survival analyses employing the Cox proportional hazards models and generated adjusted survival curves to examine the outcomes. The analyses were performed from three perspectives: vaccinated vs. unvaccinated patients, vaccinated and unvaccinated patients grouped by age, and stratified by vaccination status. Results: Results indicate a substantial correlation between vaccination and a 20% reduction in the risk of case-fatality. Age-specific effects reveal varying degrees of protection across different age groups. Conclusion: These findings emphasize the pivotal role of vaccination status in COVID-19 risk assessment, supporting the development of a clinical decision support system for accurate predictions and optimizing healthcare management at admission.
TinyJAMBU Hardware Implementation For Low Power
(2024-08-05) Fernández García, Carlos; Mora Gutiérrez, José Miguel; Jiménez Fernández, Carlos Jesús; Universidad de Sevilla. Departamento de Tecnología Electrónica
In this paper, we present hardware implementations of the lightweight TinyJAMBU cipher with reduced power consumption using a mechanism based on shift register parallelization. The power consumption in digital circuits depends linearly on the switching activity of the logic gates. The parallelization technique reduces the number of switches per clock cycle of the shift registers, which can significantly reduce power consumption. This technique has been applied to the TinyJAMBU cipher, a f inalist in the NIST lightweight cryptography standardization process with the lowest resource and power consumption. The implementations we present use the logical parallelization technique in the cipher’s NLFSR, which is the basic block of TinyJAMBU, and in the key register. Simulation results are presented to demonstrate the effectiveness of the proposed technique in reducing power consumption, achieving a reduction of more than 30% in dynamic power consumption compared to the standard implementation, with almost no increase in resource consumption. Therefore, the ciphers proposed in this paper are highly suitable for use in applications with severe constraints on available resources and power.
Application specific integrated circuit solution for multi-input multi-output piecewise-affine functions
(Wiley, 2016-01) Brox Jiménez, Piedad; Martínez Rodríguez, Macarena Cristina; Tena Sánchez, Erica; Baturone Castillo, María Iluminada; Acosta Jiménez, Antonio José; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; European Commission (EC); Gobierno de España; Consejo Superior de Investigaciones Científicas (CSIC); Universidad de Sevilla. TIC180: Diseño de Circuitos Integrados Digitales y Mixtos
This paper presents a fully-digital architecture and its ASIC implementation for computing Multi- Input Multi-Output (MIMO) Piecewise-Affine (PWA) functions. The work considers both PWA functions defined over regular hyper-rectangular and simplicial partitions of the input domains and also lattice piecewise-affine representations. The proposed architecture is able to implement PWA functions following different realization strategies, using a common structure with a minimized number of blocks, thus reducing power consumption and hardware resources. Experimental results obtained with an ASIC integrated in a 90-nm CMOS standard technology are provided. The proposed architecture is compared with other digital architectures in the state-of-the-art habitually used to implement model predictive control applications. The proposal is superior in power consumption (saving up to 86%) and economy of hardware resources (saving up to 40% in comparison with a mere replication of the three representations) to other proposals described in literature, being ready to be used in applications where high-performance and minimum unitary cost are required.
A Methodology for Optimized Design of Secure Differential Logic Gates for DPA Resistant Circuits
(Institute of Electrical and Electronics Engineers, 2014-06) Tena Sánchez, Erica; Castro, Javier; Acosta Jiménez, Antonio José; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; Consejo Superior de Investigaciones Científicas (CSIC); Gobierno de España; Universidad de Sevilla. TIC180: Diseño de Circuitos Integrados Digitales y Mixtos
Cryptocircuits can be attacked by third parties using differential power analysis (DPA), which uses power consumption dependence on data being processed to reveal critical information. To protect security devices against this issue, differential logic styles with (almost) constant power dissipation are widely used. However, to use such circuits effectively for secure applications it is necessary to eliminate any energy-secure flaw in security in the shape of memory effects that could leak information. This paper proposes a design methodology to improve pull-down logic configuration for secure differential gates by redistributing the charge stored in internal nodes and thus, removing memory effects that represent a significant threat to security. To evaluate the methodology, it was applied to the design of AND/NAND and XOR/XNOR gates in a 90 nm technology, adopting the sense amplifier based logic (SABL) style for the pull-up network. The proposed solutions leak less information than typical SABL gates, increasing security by at least two orders of magnitude and with negligible performance degradation. A simulation-based DPA attack on the Sbox9 cryptographic module used in the Kasumi algorithm, implemented with complementary metal-oxide-semiconductor, SABL and proposed gates, was performed. The results obtained illustrate that the number of measurements needed to disclose the key increased by much more than one order of magnitude when using our proposal. This paper also discusses how the effectivenness of DPA attacks is influenced by operating temperature and details how to insure energy-secure operations in the new proposals.
Logic Minimization and Wide Fan-In Issues in DPL-Based Cryptocircuits Against Power Analysis Attacks
(Wiley, 2019-02) Tena Sánchez, Erica; Acosta Jiménez, Antonio José; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; Consejo Superior de Investigaciones Científicas (CSIC); Gobierno de España; Universidad de Sevilla. TIC180: Diseño de Circuitos Integrados Digitales y Mixtos
This paper discusses the use of logic minimization techniques and wide fan-in primitives and how the design and evaluation of combinational blocks for full-custom dual-precharge-logic-based cryptocircuits affect security, power consumption, and hardware resources. Generalized procedures for obtaining optimized solutions were developed and applied to the gate-level design of substitution boxes, widely used in block ciphers, using sense-amplifier–based logic in a 90-nm technology. The security of several proposals was evaluated with simulation-based correlation power analysis attacks, using the secret key measurements to disclosure metric. The simulation results showed increased security-power-delay figures for our proposals and, surprisingly, indicated that those solutions which minimized area occupation were both the most secure and the most power-efficient.
Potential of Large Language Models in Health Care: Delphi Study
(JMIR Publications, INC, 2024-05-13) Denecke, Kerstin; May, Richard; Rivera Romero, Octavio; de Arriba-Muñoz, Antonio; Chapman, Wendy; Chow, James C.L.; Lacalle Remigio, Juan Ramón; Ropero Rodríguez, Jorge; Sevillano Ramos, José Luis; Verspoor, Karin; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Medicina Preventiva y Salud Pública; Universidad de Sevilla. Departamento de Arquitectura y Tecnología de Computadores
Background: A large language model (LLM) is a machine learning model inferred from text data that captures subtle patterns of language use in context. Modern LLMs are based on neural network architectures that incorporate transformer methods. They allow the model to relate words together through attention to multiple words in a text sequence. LLMs have been shown to be highly effective for a range of tasks in natural language processing (NLP), including classification and information extraction tasks and generative applications. Objective: The aim of this adapted Delphi study was to collect researchers’ opinions on how LLMs might influence health care and on the strengths, weaknesses, opportunities, and threats of LLM use in health care. Methods: We invited researchers in the fields of health informatics, nursing informatics, and medical NLP to share their opinions on LLM use in health care. We started the first round with open questions based on our strengths, weaknesses, opportunities, and threats framework. In the second and third round, the participants scored these items. Results: The first, second, and third rounds had 28, 23, and 21 participants, respectively. Almost all participants (26/28, 93% in round 1 and 20/21, 95% in round 3) were affiliated with academic institutions. Agreement was reached on 103 items related to use cases, benefits, risks, reliability, adoption aspects, and the future of LLMs in health care. Participants offered several use cases, including supporting clinical tasks, documentation tasks, and medical research and education, and agreed that LLM-based systems will act as health assistants for patient education. The agreed-upon benefits included increased efficiency in data handling and extraction, improved automation of processes, improved quality of health care services and overall health outcomes, provision of personalized care, accelerated diagnosis and treatment processes, and improved interaction between patients and health care professionals. In total, 5 risks to health care in general were identified: cybersecurity breaches, the potential for patient misinformation, ethical concerns, the likelihood of biased decision-making, and the risk associated with inaccurate communication. Overconfidence in LLM-based systems was recognized as a risk to the medical profession. The 6 agreed-upon privacy risks included the use of unregulated cloud services that compromise data security, exposure of sensitive patient data, breaches of confidentiality, fraudulent use of information, vulnerabilities in data storage and communication, and inappropriate access or use of patient data. Conclusions: Future research related to LLMs should not only focus on testing their possibilities for NLP-related tasks but also consider the workflows the models could contribute to and the requirements regarding quality, integration, and regulations needed for successful implementation in practice.
Transformer Models in Healthcare: A Survey and Thematic Analysis of Potentials, Shortcomings and Risks
(Springer Nature, 2024) Denecke, Kerstin; May, Richard; Rivera Romero, Octavio; Universidad de Sevilla. Departamento de Tecnología Electrónica
Large Language Models (LLMs) such as General Pretrained Transformer (GPT) and Bidirectional Encoder Representations from Transformers (BERT), which use transformer model architectures, have significantly advanced artificial intelligence and natural language processing. Recognized for their ability to capture associative relationships between words based on shared context, these models are poised to transform healthcare by improving diagnostic accuracy, tailoring treatment plans, and predicting patient outcomes. However, there are multiple risks and potentially unintended consequences associated with their use in healthcare applications. This study, conducted with 28 participants using a qualitative approach, explores the benefits, shortcomings, and risks of using transformer models in healthcare. It analyses responses to seven open-ended questions using a simplified thematic analysis. Our research reveals seven benefits, including improved operational efficiency, optimized processes and refined clinical documentation. Despite these benefits, there are significant concerns about the introduction of bias, auditability issues and privacy risks. Challenges include the need for specialized expertise, the emergence of ethical dilemmas and the potential reduction in the human element of patient care. For the medical profession, risks include the impact on employment, changes in the patient-doctor dynamic, and the need for extensive training in both system operation and data interpretation.
Engine and oil condition analysis using a hybrid supervised model with multi-layer neural network and expert rules
(Institute of Electrical and Electronics Engineers, 2024-10) Ochando Terreros, Francisco José; Guerrero Alonso, Juan Ignacio; Luque Rodríguez, Joaquín; León de Mora, Carlos; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. TIC150: Tecnología Electrónica e Informática Industrial
This article relies on using machine learning algorithms for improving maintenance in military vehicles by means of a condition-based approach, allowing more precise maintenance task scheduling. The engine was chosen among several vehicle systems for its faults, effects, and criticality. We adopt a novel approach, using real-time captured operational engine data for condition-based and prognostic methods without additional sensors. Unlike other work that transmits data externally or performs oil chemical analysis, this research leverages data and expert rules for simultaneous analysis of oil use and engine health. The methodology involves data processing techniques, model training, and model testing with operational data. Operational data are used to predict friction power based on several engine parameters. The model combines expert lubrication rules with machine learning algorithms. These rules serve as the foundation for unknown friction power prediction using a multilayer perceptron, among other algorithms. Consequently, the model provides a crucial indicator of engine wear based on friction power. Unlike other models, the proposed model eliminates the need for incorporating viscosity sensors, thus avoiding the complexity of installing such sensors in vehicles. A performance analysis was conducted to identify the most efficient algorithm for developing a lightweight model suitable for installation on an edge computer. Empirical validation revealed a correlation between the cumulative friction power and metal concentration in the oil samples.
The use of high-intensity focused ultrasound for the rewarming of cryopreserved biological material
(IEEE, 2021) Olmo Fernández, Alberto; Barroso, Pablo; Barroso, Fátima; Risco, Ramón; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Física Aplicada III
High-intensity focused ultrasound (HIFU) has been used in differentmedical applications in the last years. In this work, we present for the first time the use of HIFU in the field of cryopreservation, the preservation of biological material at low temperatures. An HIFU system has been designed with the objective of achieving a fast and uniform rewarming in organs, key to overcome the critical problem of devitrification. The finite-element simulations have been carried out using COMSOL Multiphysics software. An array of 26 ultrasonic transducers was simulated, achieving an HIFU focal area in the order of magnitude of a model organ (ovary). A parametric study of the warming rate and temperature gradients, as a function of the frequency and power of ultrasonicwaves,was performed.An optimal value for these parameters was found. The results validate the appropriateness of the technique,which is of utmost importance for the future creation of cryopreserved organ banks.
Alternative General Fitting Methods for Real-Time Cell-Count Experimental Data Processing
(Institute of Electrical and Electronics Engineers, 2020-07-20) Serrano Viseas, Juan Alfonso; Pérez García, Pablo; Huertas Sánchez, Gloria; Yúfera García, Alberto; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICINN). España
This paper reports two general methods for extraction of cell-electrode electrical model parameters in cell culture (CC) assays. The presented approaches can be applied to CC assays based on electrical cell-substrate impedance spectroscopy (ECIS) technique for real-time supervision, providing the cell number per square centimeter, i.e., the cell density, as main result. Both of the proposed methods - minimization of system equations and data predictive model - search, during the experiment, the optimum values of the electrical model parameters employed for the electrode-cell model. The results of this search enable a fast and efficient calculation of the involved cell-electrode model parameters and supply real-time information on the cell number. For the sake of experimental validation, we applied the proposed methods to practical CCs in cell growth assays with a cell line of AA8 Chinese hamster ovarian fibroblasts and the Oscillation Based Test technique for bioimpedance measurements. These methods can be easily extrapolated to any general cell lines and/or other bioimpedance test methodologies.
Bioimpedance Spectroscopy-Based Edema Supervision Wearable System for Noninvasive Monitoring of Heart Failure
(Institute of Electrical and Electronics Engineers, 2023-05-17) Fernández Scagliusi, Santiago Joaquín; Giménez Miranda, Luis; Pérez García, Pablo; Martín Fernández, Daniel; Medrano Ortega, Francisco Javier; Huertas Sánchez, Gloria; Yúfera García, Alberto; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Medicina; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; Universidad de Sevilla. Departamento de Biología Celular; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; Instituto de Salud Carlos III
Heart failure (HF) is a complex syndrome in which the heart is unable to pump enough blood containing oxygen and nutrients to meet the body's demands. HF is the leading cause of hospitalization for patients over 65 years of age. After a patient is diagnosed with HF, the mortality rate is 50% within the first five years. Presently, there are no unanimous diagnostic criteria for HF. Bioimpedance (BI) analysis has been proposed in recent years as a technique to detect one of the main symptoms: changes in body volume due to edema. This research presents a portable device (Volum), capable of performing real-time BI measurements in a low-cost and noninvasive way. The goal is to improve patient monitoring at home to ensure rapid intervention in cases of worsening conditions, either with timely hospitalizations or adjustments to a patient's usual treatment. Volum is a small, wearable, wireless, lightweight, low-power clinical pilot prototype that takes measurements through four electrodes and sends the data via Bluetooth to an Android device.
A Plethysmography Capacitive Sensor for Real-Time Monitoring of Volume Changes in Acute Heart Failure
(Institute of Electrical and Electronics Engineers, 2021-06-23) Rando, Enrique; Pérez García, Pablo; Scagliusi, Santiago F.; Medrano Ortega, Francisco Javier; Huertas Sánchez, Gloria; Yúfera García, Alberto; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Medicina; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; Instituto de Salud Carlos III
A small, wearable, low-weight, and low-power-consumption device for plethysmography capacitive sensing is proposed herein. The device allows carrying out real-time monitoring of leg volume changes in patients suffering from heart failure (HF) conditions. The dynamic of fluid overload in patients with acute HF serves as a prognosis marker for this type of severe disease and, consequently, these patients can benefit from a wearable monitoring system to measure their body volume evolution during and after hospitalization. Our approach is based on contactless capacitive wearable structures implemented by two different sensor realizations located in the ankle: 180°-parallel capacitor plates (two modes of operations are compared, with the patient's body connected to ground and to the average voltage between plates) and planar-parallel capacitor plates whose overlapped surface varies with the volume of the patient's leg. Both realizations exhibit good sensitivity to leg volume changes. The acquisition of capacitance values is performed via a simple circuit that achieves notable performance in simulated volume analysis. A preliminary pilot clinical prototype is described as well.
Design of Wearable Textile Electrodes for the Monitorization of Patients with Heart Failure
(MDPI, 2024-06-04) Sánchez, María Jesús; Fernández Scagliusi, Santiago Joaquín; Giménez Miranda, Luis; Pérez García, Pablo; Medrano Ortega, Francisco Javier; Olmo Fernández, Alberto; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Medicina; La Caixa Banking Foundation; Instituto de Salud Carlos III; Universidad de Sevilla. TIC178: Diseño y Test de Circucitos Integrados de Señal Mixta
Heart failure is a severe medical condition with an important worldwide incidence that occurs when the heart is unable to efficiently pump the patient’s blood throughout the body. The monitoring of edema in the lower limbs is one of the most efficient ways to control the evolution of the condition. Impedance spectroscopy has been proposed as an efficient technique to monitor body volume in patients with heart failure. It is necessary to research new wearable devices for remote patient monitoring, which can be easily worn by patients in a continuous way. In this work, we design and implement new wearable textile electrodes for the monitoring of edema evolution in patients with heart failure. Impedance spectroscopy measurements were carried out in 5 healthy controls and 2 patients with heart failure using our wearable electrodes for 3 days. The results show the appropriateness of impedance spectroscopy and our wearable electrodes to monitor body volume evolution. Impedance spectroscopy is shown to be an efficient marker of the presence of edema in heart failure patients. Initial patient positive feedback was obtained for the use of the wearable device.
Design and Implementation of a Smart AC Current Source for Impedance Spectroscopy Using ARM Microcontrollers
(MDPI, 2024-11-28) Meléndez-Muñoz, Salvador; Silvestre Mérida, Emilio; Fernández Scagliusi, Santiago Joaquín; Oprescu, Andreea M. ; Algarín Pérez, Antonio; Pérez García, Pablo; Universidad de Sevilla. Departamento de Tecnología Electrónica; Ministerio de Asuntos Económicos y Transformación Digital; Universidad de Sevilla. TIC178: Diseño y Test de Circucitos Integrados de Señal Mixta
This paper explores the development of a low-cost alternating current (AC) smart current generator using ARM Cortex-M33 microcontrollers with integrated peripherals, Digital to Analog Converters (DAC) and Operational amplifiers (OPAMPS). The system generates an AC voltage signal through the DAC, which is then converted to an AC using integrated operational amplifiers and passive components. The proposed design provides a compact, low-power, cost-effective solution which is suitable for optimized embedded system sensor design. Results show a signal-to-noise ratio (SNR) of up to 70 dB and a total harmonic distortion (THD) as low as 0.2%, illustrating the potential for advanced sensing applications.
Wearable Devices Based on Bioimpedance Test in Heart-Failure: Design Issues
(IMR Press, 2024-09-09) Fernández Scagliusi, Santiago Joaquín; Giménez Miranda, Luis; Pérez García, Pablo; Olmo Fernández, Alberto; Huertas Sánchez, Gloria; Medrano Ortega, Francisco Javier; Yúfera García, Alberto; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla. Departamento de Medicina; Universidad de Sevilla; Hospital Universitario Virgen del Rocío; Fundación FISEVI; La Caixa Banking Foundation; Universidad de Sevilla. TIC178: Diseño y Test de Circucitos Integrados de Señal Mixta
Heart-failure (HF) is a severe medical condition. Physicians need new tools to monitor the health status of their HF patients outside the hospital or medical supervision areas, to better know the evolution of their patients’ main biomarker values, necessary to evaluate their health status. Bioimpedance (BI) represents a good technology for sensing physiological variables and processes on the human body. BI is a non-expensive and non-invasive technique for sensing a wide variety of physiological parameters, easy to be implemented on biomedical portable systems, also called “wearable devices”. In this systematic review, we address the most important specifications of wearable devices based on BI used in HF real-time monitoring and how they must be designed and implemented from a practical and medical point of view. The following areas will be analyzed: the main applications of BI in heart failure, the sensing technique and impedance specifications to be met, the electrode selection, portability of wearable devices: size and weight (and comfort), the communication requests and the power consumption (autonomy). The different approaches followed by biomedical engineering and clinical teams at bibliography will be described and summarized in the paper, together with results derived from the projects and the main challenges found today.
Integrated sensors for electric stimulation of stem cells: A review on microelectrode arrays (MEAs) based systems
(Elsevier, 2025-06) Algarín Pérez, Antonio; Martín Fernández, Daniel; Daza Navarro, María Paula; Huertas Sánchez, Gloria; Yúfera García, Alberto; Universidad de Sevilla. Departamento de Biología Celular; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; Universidad de Sevilla. Departamento de Tecnología Electrónica; Ministerio de Ciencia e Innovación (MICIN). España
This paper provides an update on the sensors and actuators involved in Stem Cells (SC) differentiation processes based on electric stimulation (STIM), including both current and future progress. These techniques are applied in a range of biological and medical protocols, including cell linage derivation, tissue engineering, cellular therapy, cancer research, and cell motility. The typical methodology of SC electric STIM endeavors to emulate biological processes by applying an electrical signal to the cell culture and evaluating the cell response. Cell metabolism is electrically sensitive, responding in some manner to a given stimulus. The precise mechanism by which this occurs is not fully understood, but it is evident that changes in ion density at the cell membrane proximity must excite the cell metabolism (receptors), thereby activating its “differentiation” in response. In order to gain a deeper insight into the cellular mechanisms involved in this process, the physical variables should be better recognized, measured, and quantified during the protocol execution. This work is contributing to the development of a compilation of proposed systems, and specifications required, to identify and better understand the local conditions within the cell environment that are responsible for the activation of the differentiation processes. It is crucial that STIM systems are optimally designed and that the cell response is correctly understood. Two features will be reviewed: the setup employed and the circuits for STIM and monitoring. The nexus between these two elements are the electrodes, and this work will therefore be devoted to the realization of integrated Micro-Electrode Arrays (MEAs), and the design problems associated with it. The focus will be on MEAs, with the same size scale as the cells, and the design issues related to integrated electrodes, under electric stimulation, voltage or current modes.
The Role of Kano Model in Revealing the Most Significant Physicochemical Properties of Wines
(IEEE. Institute of Electrical and Electronics Engineers, 2024-11-06) Luque Sendra, Amalia; Mazzoleni, Mirko; Heras García de Vinuesa, Ana de las; Ferramosca, Antonio; Previdi, Fabio; Carrasco Muñoz, Alejandro; Universidad de Sevilla. Departamento de Ingeniería del Diseño; Universidad de Sevilla. Departamento de Tecnología Electrónica; Universidad de Sevilla; Universidad de Sevilla. TEP990: Proyectos de Ingeniería
In this article a methodology, based on the Kano model, to prioritize the features of a product or service is proposed. Instead of using detailed, lengthy, burdensome, time-demanding, and biased-prone questionnaires, enquiring the user satisfaction with each product feature, a simplified survey asking for the overall satisfaction with the product is used. The proposed method starts by training a machine learning (ML) model using a dataset of different instances of the product and the corresponding perceived quality. This model is then employed to derive the relationship between each feature and the satisfaction associated with them. The shape of this relationship is interpreted according to a Kano model placing each attribute in a bidimensional Kano map which is later partitioned using ML clustering techniques. This methodology has been applied to an open dataset containing the physicochemical characteristics of hundreds of wines and the corresponding scores obtained in a blind tasting evaluation. The research has shown that ML models get very remarkable results predicting the perceived quality of a wine and is able to build a Kano map of the wine features. The ML clustering techniques employed partitioning this Kano map has clearly overperformed conventional rectangular or polar segmentation. It has also been shown that using four categories of features, as it is proposed in the Kano model, is the most reasonable partition from an ML clustering perspective.
NanoBoot: A Field-Programmable Gate Array/System-on-Chip Hardware Boot Loader for IoT Devices
(MDPI, 2024-09-20) Ruiz de Clavijo Vázquez, Paulino; Cano Quiveu, Germán; Juan Chico, Jorge; Bellido Díaz, Manuel Jesús; Viejo Cortés, Julián; Guerrero Martos, David; Ostúa Arangüena, Enrique; Universidad de Sevilla. Departamento de Tecnología Electrónica; Ministerio de Transformación Digital y Función Pública. España; European Union; Universidad de Sevilla. TIC204: Investigación y Desarrollo Digital
This paper presents a new boot loader scheme for embedded devices with file system support built as a hardware module. The work focuses on improving the boot loader hardware and the possibility of carrying out a full boot-up process from the dedicated on-chip hardware, using a light file system to store an operating system kernel. To do so, the new full-hardware boot loader is integrated into two Field-Programmable Gate Array (FPGA) System-on-Chip (SoC), capable of launching a Linux kernel from a formatted removable media.

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