Artículos (Electrónica y Electromagnetismo)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10839

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Mostrando 1 - 20 de 531

Workload Compression Techniques to Scale Defect-Centric BTI Models to the Circuit Level
(Institute of Electrical and Electronics Engineers (IEEE), 2025-05) Santana Andreo, Andrés; van Santen, Victor M.; Castro-López, Rafael; Roca, Elisenda; Amrouch, Hussam; Fernández Fernández, Francisco Vidal; Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España
Bias Temperature Instability (BTI) poses a significant challenge in ensuring the reliability of digital systems, affecting the delay of digital logic gates, which ultimately can lead into timing failures. Sophisticated defect-centric models have been developed and successfully calibrated against empirical data to forecast the impacts of BTI at the device level. However, their application to large-scale digital circuits operating under realistic workloads over typical system lifetimes is limited because of the computational complexity of defect-centric models. To make the application of aging models in that context feasible, a useful technique is to compress the transistor workloads into simplified and hence manageable representative workloads. While fast in terms of execution speed, previous techniques struggle with accuracy when predicting aging degradation, and can reach a very high average error in threshold voltage increase prediction. In this work, we review the compression techniques described in the literature and propose two novel approaches that surpass existing ones in terms of accuracy, which is demonstrated for a complex digital design used as benchmark. Specifically, our best compression technique matches the predictions obtained through the reference uncompressed workloads, introducing negligible error, and maintains low execution times to efficiently and accurately scale defect-centric models to the circuit level.
Low-Cost and Fully Metallic Reconfigurable Leaky-Wave Antenna Based on 3D-Printing Technology for Multi-Beam Operation
(MDPI, 2025-11-30) Díaz-Martín, Miguel; Molero Jiménez, Carlos; Martínez-García, Ginés; Baena Molina, Marcos; Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España
Global data consumption is experiencing exponential growth, driving the demand for wireless links with higher transmission speeds, lower latency, and support for emerging applications such as 6G. A promising approach to address these requirements is the use of higher-frequency bands, which in turn necessitates the development of advanced antenna systems. This work presents the design and experimental validation of a reconfigurable, low-cost leaky-wave antenna capable of controlling the propagation direction of single-, dual-, and triple-beam configurations in the FR3 frequency band. The antenna employs slotted periodic patterns to enable directional electromagnetic field leakage, and it is based on a cost-effective and simple 3D-printing fabrication process. Laboratory testing confirms the theoretical and simulated predictions, demonstrating the feasibility of the proposed antenna solution.
In-Pixel Time-Gating: Handling Activity in a PFM Event-Based Image Sensor with AER Readout
(IEEE, 2025-12) Palomeque Mangut, Sergio; Leñero Bardallo, Juan Antonio; Gómez Merchán, Rubén; De La Rosa Vidal, Rafael; Rodríguez Vázquez, Ángel Benito; Electrónica y Electromagnetismo
The spiking camera, which encodes light intensities into an asynchronous pulse stream, holds great promise for event-based and high dynamic range (HDR) applications. However, standard address event representation (AER) circuits can saturate due to intense pixel firing activity, creating greedy paths in arbitration trees that give exclusive attention to certain regions. This article addresses that challenge through a novel in-pixel spike filter, which blocks new spikes from being transmitted while the readout circuits process previously stored requests, effectively distributing the attention of the arbiter tree. To evaluate the technique, we designed and fabricated a 96 × 64 spiking image sensor in a standard 180-nm CMOS technology. Experimental results confirm that this time-gating mechanism ensures a sparser readout of the spike data, managing the activity load in the arbiters while preserving the original information of the spike data. Besides, the window indirectly extends the sensor’s DR and throughput by allowing higher spiking rates under high activity and short integration times without saturating the readout channel. Also, it provides a tunable tradeoff between data compression and image quality, opening new methods for event-driven applications requiring efficient data usage.
From Systematic to Intelligent: Assessing AI-Empowered Optimization Techniques for Analog Building Block Sizing
(IEEE Access, 2025-10) Hao, Yijia; Gandara, Miguel; Mitra, Srinjoy; Strackx, Maarten; Cochran, Sandy; Fernández Fernández, Francisco Vidal; Li, Shaolan; Liu, Bo; Electrónica y Electromagnetismo; Consejo de Investigación en Ingeniería y Ciencias Físicas
This paper presents a comprehensive, design-insight-based comparison between an artificial intelligence (AI)-empowered optimization-based analog building block sizing framework and the conventional manual design methodology. Although recent AI-empowered approaches are showing high performance, conventional systematic manual design methods such as the gm/ID-based sizing are still the most widely used methods in the analog IC design community. This raises the necessity of the comprehensive comparative analyses between the two kinds of methods. To fill this gap, this paper compares the optimal designs obtained by a typical method of the former with those obtained by the latter method in the literature/industry. Four case studies, including a comparator, an amplifier (both standard and low power design), and an oscillator, using technology nodes ranging from 0.35 µm to 65 nm, are presented. Detailed performance evaluations and design insights are presented for each case study, with silicon validation provided for three designs. Our findings highlight that AI-empowered sizing not only meets but often surpasses conventional designs in key performance metrics, while still benefiting from designer interaction to align with design intents.
ColorPhAST: a visual rapid colorimetric assay for detecting phage-susceptibility in Escherichia coli
(Frontiers Media S.A., 2025-07-11) Gómez Estévez, Paula; Rodríguez Villodres, Ángel; Gálvez Benítez, Lydia; Martín Gutiérrez, Guillermo; Cisneros, José Miguel; Rosa Utrera, José Manuel de la; Lepe Jiménez, José Antonio; Genética; Medicina; Electrónica y Electromagnetismo; Instituto de Salud Carlos III; Ministerio de Ciencia, Innovación y Universidades (MICIU). España
The alarming increase in the prevalence of multidrug-resistant microorganisms, which in some cases has left no available treatment options, has led to a renewed interest in previously abandoned therapeutic approaches such as bacteriophage therapy. Therefore, the development of rapid methods for determining phage susceptibility will be essential in the near future because phage-based treatments could provide a viable alternative for patients with infections caused by multidrugresistant microorganisms. In response to this need, a new test named ColorPhAST (Color Phage Activity Susceptibility Test) based on color change of red phenol has been designed to detect phage-susceptibility in just 2 h. A total of 100 Escherichia coli isolates were used to evaluate the performance of the test, 55 being resistant to the isolated phage through the double agar overlay spot assay (gold standard method). The sensitivity and specificity of the test were 95.6 and 100%, respectively. The ColorPhAST is a fast, easy-to-performed, and accurate method with great potential for identifying susceptibility to bacteriophages.
A Selective Chromogenic Medium for Detecting Meropenem-Resistant Pseudomonas aeruginosa in Respiratory Samples
(MDPI, 2025-05-09) Cintora Mairal, Carmen; Martín Gutiérrez, Guillermo; Rodríguez Villodres, Ángel; Cisneros, José Miguel; Lepe Jiménez, José Antonio; Rosa Utrera, José Manuel de la; Microbiología; Medicina; Electrónica y Electromagnetismo; Instituto de Salud Carlos III; Ministerio de Ciencia, Innovación y Universidades (MICIU). España
Background/Objectives: Meropenem is widely used to treat Pseudomonas aeruginosa infections; however, the pathogen’s increasing resistance compromises its efficacy. In this study, we aimed to develop a selective culture medium for detecting the presence of meropenem-resistant Pseudomonas aeruginosa in respiratory specimens within 24 h. Methods: The medium’s performance was challenged using a collection of 130 clinical Pseudomonas aeruginosa strains (of which 85 were meropenem-susceptible, 14 were meropenemintermediate, and 21 were meropenem resistant). Subsequently, clinical validation was carried out using 130 respiratory samples. Results: The selective medium demonstrated excellent sensitivity (average 98.7%) and specificity (average 90%) across bacterial concentrations ranging from 1 × 104 to 1 × 108 CFU/mL, and a high negative predictive value (average 99.2%) compared to the broth microdilution (BMD) method. Clinical validation with bronchoalveolar lavage (BAL) and tracheobronchial aspirate (TBA) clinical specimens (N = 130) revealed a strong performance, with 92,3% categorical agreement. Conclusions: This method accelerates susceptibility testing, is user-friendly, and delivers reliable results, contributing to the optimization of empirical treatment for respiratory tract infections.
Highly Scalable Real Time Epilepsy Diagnosis Architecture Via Phase Correlation
(Elsevier BV, 2017-07-13) Romaine, James Brian; Delgado Restituto, Manuel; Rodríguez Vázquez, Ángel Benito; Electrónica y Electromagnetismo; Ministerio de Economia, Industria y Competitividad (MINECO). España; Junta de Andalucía; Office of Naval Research (ONR). United States; European Union (UE)
Accurate Ray-Tracing Modeling of Radiation From Leaky-Wave Antennas
(Institute of Electrical and Electronics Engineers, 2025-09-08) Poveda García, Miguel; Mesa Ledesma, Francisco Luis; Gómez Tornero, José Luis; Quevedo Teruel, Óscar; Algaba Brazalez, Astrid; Electrónica y Electromagnetismo; Física Aplicada I; Ministerio de Ciencia e Innovación (MICIN). España; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Gobierno de España; TIC112: Microondas
In this letter, we propose the use of a radial ray-tracing approach to accurately model the radiation from leaky-wave antennas (LWAs). The technique involves the launching of several sets of rays that emanate radially from different source points along the LWA aperture. The trajectory of the emitted rays is determined and applied to accurately evaluate the impact of every source point on the radiation pattern of the LWA, with particular attention to complex setups incorporating dielectric lenses. Each source point’s contribution is superimposed, weighted by a complex factor related to the LWA’s leaky mode. The method demonstrates both efficiency and accuracy in modeling radiation patterns for different taperings of the leaky mode used to generate shaped beams, leading to a significant reduction in computation time compared to commercial full-wave solvers.
Design of Broadband Aperture-Stacked Patch Microstrip Antennas Based on Third Order Filtering Equivalent Circuits
(Institute of Electrical and Electronics Engineers, 2025-12-05) Delgado Lozano, Ignacio María; Rodríguez Boix, Rafael; Losada Torres, Vicente; Fernández Prieto, Armando; Electrónica y Electromagnetismo; Física Aplicada I; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); TIC112: Microondas
In this paper the authors describe the design of a broadband aperture-stacked patch (ASP) microstrip antenna based on a filtering equivalent circuit. The antenna consists of two stacked microstrip patches that are fed by a microstrip line through a resonant aperture. An equivalent circuit is proposed for the antenna consisting of three LC parallel resonators, out of which two resonators are inductively coupled and two resonators are capacitively coupled. The equivalent circuit is de-embedded from the antenna response by means of the least squares method, and the dimensions of the antenna are adjusted in such a way their equivalent circuit matches the response of a broadband third order filter. The reference filter is used as a mean to ensure broadband matching of the antenna. Following this design strategy, a broadband ASP antenna has been designed, fabricated and measured at a center frequency of 5.5 GHz with a bandwidth of roughly 45%.
Modeling the Photovoltaic Diode Region for High Dynamic Range Image Sensor Design
(Institute of Electrical and Electronics Engineers, 2025-11-27) Fernández Peramo, Pablo; Leñero Bardallo, Juan Antonio; Rodríguez Vázquez, Ángel Benito; Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; Ministerio para la Transformación Digital y de la Función Pública. España
This work presents an analytical model for the dependence of the open-circuit voltage of CMOS diodes operating in the photovoltaic (PV) regime versus illuminance and temperature. The model is targeted for image sensor design and provides insights into key behavioral features relevant to high dynamic range (HDR) image acquisition, including the steady-state response, sensitivity, bandwidth, noise, and signal-to-noise ratio (SNR) under varying illuminance and temperature conditions. The article also includes experimental data to confirm the adequacy of the proposed model in predicting the behavior of practical photodiodes. These findings highlight the suitability of a PV diode as the photoreceptor stage for HDR imaging applications, offering improved compactness and noise performance over conventional logarithmic photoreceptors while operating without static power consumption as a result of its self-biased nature.
Sample-Controlled analysis under high pressure for accelerated process studies
(Wiley, 2018-07-23) Perejón Pazo, Antonio; Sánchez Jiménez, Pedro Enrique; Soria del Hoyo, Carlos; Valverde Millán, José Manuel; Criado, José Manuel; Pérez Maqueda, Luis A.; Química Inorgánica; Electrónica y Electromagnetismo; Ministerio de Economía y Competitividad (MINECO). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
The potential of controlled rate thermal analysis (CRTA) for studying high-pressure gas-solid processes has been evaluated. CRTA is a type of smart temperature program based on a feedback system that uses any experimental signal related to the process evolution for commanding the temperature evolution. In this work, an instrument that uses the gravimetric signal for CRTA control has been designed and used for the study of two high-pressure gas-solid reactions: the highly exothermic thermal oxidation of TiC under high pressure of oxygen and the reduction in Fe2O3 under high pressure of hydrogen. Advantages of CRTA for discriminating overlapping processes and appraising kinetic reaction mechanisms are shown.
Kyber AHE: An Easy-to-Implement Additive Homomorphic Encryption Scheme Based on Kyber and Its Application in Biometric Template Protection
(MDPI, 2025-09-09) Román Hajderek, Roberto; Arjona López, María Rosario; Baturone Castillo, María Iluminada; Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Union (UE); Ministerio para la Transformación Digital y de la Función Pública. España
Homomorphic encryption solutions tend to be costly in terms of memory and computational resources, making them difficult to implement. In this paper, we present Kyber AHE, a lightweight additive homomorphic encryption scheme for computing the addition modulo 2 of two binary strings in the encrypted domain. It is based on the CRYSTALS-Kyber public key encryption (PKE) scheme, which is the basis of the NIST module-lattice-based key-encapsulation mechanism standard. Apart from being quantum-safe, Kyber PKE has other interesting features such as the use of compressed ciphertexts, reduced sizes of keys, low execution times, and the ability to easily increase the security level. The operations performed in the encrypted domain by Kyber AHE are the decompression of ciphertexts, the component-wise modulo q addition of polynomials, and the compression of the results. A great advantage of Kyber AHE is that it can be easily implemented along with CRYSTALS-Kyber without the need for additional libraries. Among the applications of homomorphic encryption, biometric template protection schemes are a promising solution to provide data privacy by comparing biometric features in the encrypted domain. Therefore, we present the application of Kyber AHE for the protection of biometric templates. Experimental results have been obtained using Kyber AHE in an iris biometric template protection scheme with 256-byte features using Kyber512, Kyber768, and Kyber1024 instances. The sizes of the encrypted iris features are 6.0, 8.5, and 12.5 kB for NIST security levels I, III, and V, respectively. Using a commercial laptop, the encryption ranges from 0.755 to 1.73 ms, the evaluation from 0.096 to 0.161 ms, and the decryption from 0.259 to 0.415 ms, depending on the security level.
Prediction-Based Spectrum Sensing Framework for Cognitive Radio
(IEEE, 2025-08-27) Rojas Bustos, Andrés Bolívar; Follet, Gawen; Rosa Utrera, José Manuel de la; Liñan-Cembrano, Gustavo; Electrónica y Electromagnetismo; Ministerio de Economia, Industria y Competitividad (MINECO). España; Agencia Estatal de Investigación. España
This paper presents a hardware-software deep learning architecture for prediction-based spectrum sensing in Cognitive Radio (CR) applications. A convolutional neural network-based predictor for spectrum occupancy was trained using the band power from I/Q samples acquired by a software- defined radio (SDR). Additionally, a second neural engine was trained for radio frequency (RF) frame detection based on spectrograms. We implemented a transfer-learning solution using a You-Only-Look-Once version 8 nano model with a synthetic dataset comprising thousands of wireless signals, including Wi-Fi, Bluetooth, and collision frames. Once trained, the two neural networks were transferred to a Raspberry Pi 5 – an affordable single-board computer – connected to two (one for Rx, one for Tx) ADALM-PLUTO SDR systems for benchmarking using over-the-air signals in the 2.4 GHz band. Together with our methodology and experimental results, the paper also presents an overview of current spectrum prediction proposals and RF frame detectors. Remarkably, to the best of our knowledge, this proposed framework is the first approach towards an Internet of Things-suitable implementation of prediction-based spectrum sensing for CR applications.
Water-resistant hybrid perovskite solar cell - drop triboelectric energy harvester
(Elsevier, 2026) Núñez Gálvez, Fernando; García Casas, Xabier; Contreras-Bernal, Lidia; Descalzo Ruiz, Alejandro; Obrero-Pérez, José Manuel; Castillo Seoane, Javier; Ginés Arteaga, Antonio José; Leger, Gildas; Sánchez López, Juan Carlos; Espinós, Juan P.; Barranco, Ángel; Borrás, Ana; Sánchez Valencia, Juan Ramón; López Santos, Carmen; Física Aplicada I; Química Física; Física de la Materia Condensada; Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España
Hybrid energy-harvesting systems that combine perovskite solar cells (PSCs) with drop-driven triboelectric nanogenerators (D-TENGs) offer a compelling solution for continuous power generation under diverse weather conditions. Yet, the inherent vulnerability of halide perovskites to moisture and environmental stressors remains a critical barrier to their widespread deployment. To overcome this bottleneck, we introduce plasma-deposited fluorinated polymers (CFₓ) films as multifunctional encapsulation layers that simultaneously provide water resistance, triboelectric functionality, and optical transparency (>90 %). Plasma deposition enables conformal, room temperature, and solvent-free coating of complex surfaces, ensuring uniform protection without compromising photovoltaic performance. After encapsulation of PSCs with CFx films, power conversion efficiency remained virtually unchanged, and champion cells preserved a PCE of 17.9 %. More importantly, the devices exhibited high environmental stability, retaining over 50 % of their initial PCE for 10 days under high humidity and temperature. Furthermore, CFx layers enabled Spiro-OMeTAD compatibility with commercial UV-curable resins, leading to a thin-film hybrid PSC/D-TENG device capable of simultaneous solar and rain energy harvesting. This device maintained 80 % of its initial performance after 300 h of continuous illumination under humid conditions and demonstrated stability under continuous dripping and illumination for more than 5 h. We demonstrated that optimizing the chemical composition of CFx layers significantly enhances their triboelectric performance. In standalone operation, the optimized CFₓ-based D-TENG, enriched with 36.4 % of (CF2 + CF3) functional species, delivered open-circuit voltage peaks up to 110 V and a maximum power density of ∼4 mW/cm2 under rainwater droplets, while retaining over 85 % of its initial output after more than 17,000 droplet impacts. As a proof of concept, using the same CFx layer for both encapsulation and triboelectric functionality, the hybrid PSC/D-TENG device achieved short-circuit current densities of 11.6 mA/cm2 under 0.5 sun illumination and peak voltages of 12 V per raindrop, enabling simultaneous solar and rain energy harvesting. A self-charging prototype powered LED arrays via a custom boost converter, demonstrating practical multisource energy harvesting for low-power electronics.
Alternative Input Architecture for Balanced Diplexers Based on Over-Coupled H-Shaped Resonators With Independent Dual-Band Response
(Institute of Electrical and Electronics Engineers (IEEE) Xplore, 2025-10-22) Medrán del Río, José Luis; Fernández Prieto, Armando; Martel Villagrán, Jesús; Medina Mena, Francisco; Electrónica y Electromagnetismo; Física Aplicada II; Ministerio de Ciencia, Innovación y Universidades (MICIU). España
A novel technique for designing balanced-to-balanced diplexers with enhanced common-mode rejection is presented. In this approach, the conventional T-junction typically used to feed the diplexer output channels is replaced by a pair of over-coupled H-shaped resonators. Each output channel is implemented using a second-order balanced filter, also based on H-shaped resonators. These filters are independently designed using standard coupled-resonator theory and are subsequently electromagnetically coupled to a common differential input port to achieve diplexing functionality. For performance comparison, two diplexers are designed: one employing the traditional T-junction and the other utilizing the proposed over-coupled H-shaped resonators. Both simulation and measurement results confirm the superiority of the proposed architecture in terms of common-mode rejection and overall performance.
Stable levitation of a magnet over a pair of counter-rotating cylinders: The Alcon levitator
(American Institute of Physics, 2025) Pérez Izquierdo, Alberto Tomás; García Sánchez, Pablo; Electrónica y Electromagnetismo; Ministerio de Ciencia y Tecnología (MCYT). España; FQM253: Electrohidrodinámica y Medios Granulares Cohesivos
The Alcon levitator is an experimental setup that demonstrates the levitation of a bar magnet above two counter-rotating metal cylinders. Stable levitation is achieved only above a critical angular velocity – about 9000 rpm in our setup. The precise physical mechanism behind this stability remains under investigation. In this work, we combine theoretical analysis and numerical simulations to examine the mechanism, which originates from the interplay between lift and braking forces acting on the magnet and their dependence on the magnetic Reynolds number, i.e., the angular velocity of the cylinders.
Wall Repulsion of Charged Brownian Particles Subjected to Alternating Current Electric Fields in Microfluidic Channels
(American Institute of Physics, 2025-08-26) Arcenegui Troya, Juan Jesús; Fernández Mateo, Raúl; Ramos Reyes, Antonio; García Sánchez, Pablo; Electrónica y Electromagnetismo; Ministerio de Ciencia e Innovación (MICIN). España; FQM253: Electrohidrodinámica y Medios Granulares Cohesivos
This study investigates the wall repulsion of submicron particles (0.5 µm and 0.75 µm in diameter) under an alternating current (AC) electric field and evaluates whether this phenomenon can be explained by the wall-particle interaction due to Concentration Polarization Electro-Osmosis (CPEO), a theory previously validated for larger particles. Our findings confirm that CPEO, rather than electric repulsion, is the primary mechanism driving particle-wall repulsion. Experimental results show that the particle distribution across the channel width aligns with predictions from a one-dimensional Fokker-Planck model incorporating CPEO-induced repulsion. The repulsion strength decreases with increasing frequency and electrolyte conductivity, consistent with CPEO theory. This work enhances the understanding of CPEO-driven particle repulsion from walls in the Brownian regime, offering valuable insights for microfluidic applications involving submicron particles.
Concentration-Polarization Electrophoresis of charged colloidal dimers: A numerical study
(American Physical Society (APS), 2025) Flores-Mena, Jose Eladio; García-Sánchez, Pablo; Ramos Reyes, Antonio; Electrónica y Electromagnetismo; Ministerio de Ciencia e Innovación; FQM253: Electrohidrodinámica y Medios Granulares Cohesivos
We present a numerical analysis of the translational motion of dimers composed of charged dielectric particles immersed in aqueous electrolytes under AC electric fields. The dimers consist of two spheres with different radii and are studied in two distinct configurations: (i) spheres connected by a negligibly thin wire, and (ii) spheres joined by a narrow neck. We explain their net motion as a consequence of steady electro-osmotic flows generated on the particle surfaces, a phenomenon known as Concentration-Polarization Electrophoresis (CPEP). Our numerical results are compared with recent experimental observations, and we discuss the similarities and discrepancies between the two.
Integration of calcium looping and calcium hydroxide thermochemical systems for energy storage and power production in concentrating solar power plants
(Elsevier, 2023-11-15) Carro Paulete, Andrés; Chacartegui, Ricardo; Ortiz, Carlos; Arcenegui Troya, Juan Jesús; Pérez Maqueda, L. A.; Becerra González, Juan Antonio; Ingeniería Energética; Electrónica y Electromagnetismo; Junta de Andalucía; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); European Union; Ministerio de Ciencia e Innovación (MICIN). España
Energy storage is a key factor in the development of renewables-based electrical power systems. In recent years, the thermochemical energy storage system based on calcium-looping has emerged as an alternative to molten salts for energy storage in high-temperature concentrated solar power plants. This technology still presents some challenges that could be solved by integrating the thermochemical energy storage system based on calcium hydroxide. This work studies a novel concentrated solar power system integrating calcium-looping and calcium hydroxide thermochemical energy storage systems. The results show that the combined use of hydration-dehydration cycles in the calcination-carbonation processes of the calcium looping for energy storage could partially solve the issue related to the multicyclic deactivation of calcium oxide. The improvement in the conversion of calcium oxide during carbonation is demonstrated experimentally when hydration-dehydration cycles are combined. Numerical simulations demonstrate the technical feasibility of the integrated process, with efficiencies ranging between 38-46%, improved with the increase in calcium oxide conversion in the carbonator, showing the potential of the proposed integration.
Advancing infantile hemangioma diagnosis by integrating temperature, color, and texture
(Society of Photo-Optical Instrumentation Engineers (SPIE), 2025) Pérez Carrasco, José Antonio; Serrano Gotarredona, María del Carmen; Leñero Bardallo, Juan Antonio; Bernabeu Wittel, José; Acha Piñero, Begoña; Teoría de la Señal y Comunicaciones; Electrónica y Electromagnetismo; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Junta de Andalucía
Significance: Infantile hemangiomas are one of the most prevalent benign tumors in childhood. Typically, diagnosis relies on visual assessment of area, texture, and color. A few studies have focused on various color attributes in superficial and mixed Infantile hemangioma types, neglecting the deep category. Limited research has explored temperature in the location of hemangioma lesions. Aim: We seek, for the first time, to quickly identify and classify infantile hemangioma lesions using a portable, programmable handheld device. The system aims to (1) replicate a physician’s assessment of infantile hemangioma and (2) deliver an easy way to understand automatic diagnosis. Approach: The custom-built device comprises an infrared sensor and a visible light spectrum sensor to assess color and depth through computations of different color and texture features. Over a 3-year period, 53 patients were monitored, and 83 hemangioma images were captured. Results: The device accurately localized all lesions in real time and classified hemangioma lesions into three primary types using selected color and texture features. Evaluation metrics showed an average sensitivity of 0.8948 and specificity of 0.7313 for an accuracy of 0.7572 and an average sensitivity of 0.7803 and specificity of 0.8720 for an F-score of 0.7826 in the three-class classification. Conclusions: The two-sensor device accurately identifies and categorizes infantile hemangioma lesions, providing a clear automated diagnosis based on computerized features.

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