Browsing by browse.metadata.contributordepartment "Electromagnetismo y Electrónica"
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- PublicationOpen AccessA Comparison Between Refraction From an Adaptive Optics Visual Simulator and Clinical Refractions(2020) Tabernero de Paz, Juan Francisco; Otero, C.; Pardhan, S.; Electromagnetismo y Electrónica
- PublicationOpen AccessApplication of LCA Methodology to the Production of Strawberry on Substrates with Peat and Sediments from PortsLegua, P.; Hernández, F.; Martínez-font, R.; Jorquera, D.; Rosique Jimenez, C.; Electromagnetismo y Electrónica
- PublicationOpen AccessAugmented reality in teaching instrumentation in STEM subjects: immersive learning through PEARL in higher education(Universidad de Murcia, Servicio de Publicaciones, 2026-01-01) Morales Méndez, Ginés; Robles-Robles, Jesús; Lozano Avilés, Ana Belén; Electromagnetismo y Electrónica; Facultades de la UMU::Facultad de EducaciónLa comprensión y el manejo de la instrumentación es una habilidad fundamental para los estudiantes, especialmente en los campos de ciencia, tecnología, ingeniería y matemáticas (STEM). No obstante, el acceso restringido a laboratorios, la complejidad en el manejo de equipos reales y la exigencia de una supervisión experta presentan obstáculos considerables para un aprendizaje seguro y efectivo. En este marco, PEARL (Paderborner Elektrotechnik Augmented Reality Labor) emerge como una aplicación formativa innovadora que utiliza la realidad aumentada (RA). Esta plataforma permite a los usuarios interactuar de manera inmersiva con herramientas como osciloscopios, generadores de funciones, y multímetros, enriqueciendo los ambientes físicos con información aumentada para simular operaciones y procedimientos en tiempo real. Este estudio analiza su impacto en el aprendizaje a través de un enfoque cuasi-experimental que incluye grupos de control y experimental. Los resultados muestran mejoras significativas en el rendimiento técnico y en la autoconfianza del grupo que utilizó RA, así como una valoración alta en términos de usabilidad y experiencia de uso. Estos hallazgos refuerzan la efectividad de PEARL como recurso para la enseñanza de la instrumentación electrónica en educación superior, ayudando a mitigar las limitaciones de los laboratorios tradicionales y promoviendo metodologías de aprendizaje activas, accesibles y seguras.
- PublicationOpen AccessEnergías renovables y Eficiencia energética(Universidad de Murcia, 2025-09-03) Alarcón García, Mariano; Cerro Velázquez, Francisco del; Electromagnetismo y ElectrónicaDiapositivas de las presentaciones de aula de la asignatura Energías renovables y Eficiencia energética del Grado en Ingeniería Química.
- PublicationOpen AccessFunctional visual tests to evaluate the effect of small astigmatism correction with toric contact lenses(Optica Publishing Group, 2023-06-01) Gil Fernández, Pedro; Farcas, Alexandra; Benito Galindo, Antonio; Tabernero de Paz, Juan Francisco; Electromagnetismo y ElectrónicaThe prescription of daily contact lenses does not often include a full astigmatic correction. We question here whether this full astigmatic correction (for low to moderate astigmatism) provides a substantial improvement in the overall visual performance compared to a more conservative approach based only on the prescription of spherical contact lenses. The visual performance of 56 contact lens neophytes divided in two contact lens fitting groups (toric versus spherical lens fit) was assessed using standard visual acuity and contrast sensitivity tests. A new set of functional tests simulating everyday tasks was also used. Results showed that subjects with toric lenses had significantly better visual acuity and contrast sensitivity than those with spherical lenses. Functional tests did not render significant differences between groups, which was explained by several factors like i) the visual demand of the functional tests, ii) the dynamic blur due to misalignments and iii) small misfits between the available and measured axis of the astigmatic contact lens.
- PublicationOpen AccessHead motion elicited by affective pictures as measured by a new LED-based technique(Brill Academic Publishers, 2019-04-26) Kosonogov, Vladimir; Torrente Hernández, Ginesa; Arenas Dalla Vecchia, Aurelio; Carrillo Verdejo, María Eduvigis; Martínez Selva, José María; Sánchez Navarro, Juan Pedro; Electromagnetismo y ElectrónicaThe complex sensory input and motor reflexes that keep body posture and head position aligned are influenced by emotional reactions evoked by visual or auditory stimulation. Several theoretical approaches have emphasized the relevance of motor reactions in emotional response. Emotions are considered as a tendency or predisposition to act that depends on two motivational systems in the brain — the appetitive system, related to approach behaviours, and the defensive system, related to withdrawal or fight-or-flight behaviours. Few studies on emotion have been conducted employing kinematic methods, however. Motion analysis of the head may be a promising method for studying the impact of viewing affective pictures on emotional response. For this purpose, we presented unpleasant, neutral and pleasant affective pictures. Participants were instructed to view the pictures and to remain still. Two light-emitting diodes (LEDs) were attached to the foreheads of participants, and a Wii Remote controller, positioned 25 cm away, detected the position of the LEDs in the medial–lateral and anterior–posterior axes. We found more sway in response to unpleasant pictures. In addition, unpleasant pictures also provoked faster movements than both neutral and pleasant pictures. This response to unpleasant pictures, in contrast to pleasant ones, might reflect the readiness or predisposition to act. Our data also revealed that men moved faster than women, which is in accordance with previous findings related to gender differences.
- PublicationOpen Access"Hearin" Electromagnetic waves(2014) Rojo Martínez, Marta María; Muñoz Madrid, Juan; Electromagnetismo y Electrónica
- PublicationOpen AccessImpact of peripheral refractive errors in mobility performance(Association for Research in Vision and Ophthalmology, ) García Pedreño, Clara; Tabernero de Paz, Juan Francisco; Benito Galindo, Antonio; Artal Soriano, Pablo; Electromagnetismo y ElectrónicaPurpose: The purpose of this study was to investigate the functional effects of peripheral refractive errors on mobility performance through a stair negotiation task. Methods: Twenty-one young, normal sighted subjects navigated through an obstacle with steps, wearing spectacles that altered only their peripheral refraction. Lenses were used to induce positive defocus (+2 diopters [D] and +4 D), negative defocus (−2 D and −4 D), or astigmatism (+1.75 D and −3.75 D, axis 45 degrees) in the periphery. Feet trajectories were analyzed, and several gait assessment parameters were obtained. Statistical tests were conducted to determine significant performance differences between the lenses. Peripheral refraction in each subject was measured using a scanning Hartmann-Shack wavefront sensor to assess the impact of intrinsic peripheral refraction on the experiment. Results: Statistically significant differences in performance appeared when peripheral errors were superimposed. Crossing time with respect to plano lenses increased by 6.2%, 7.6%, 19.2%, and 29.6% for the −2 D, +2 D, −4 D, and +4 D lenses, respectively (P < 0.05 in the last 3 cases). Subjects exhibited slower walking speeds, increased step count, and adopted precautionary measures. High-power positive defocus lenses had the biggest impact on performance, and differences were observed in distance to steps between induced positive and negative defocus. Conclusions: In this laboratory-based study without an adaptation period, peripheral refractive errors affected stair negotiation, causing cautious behavior in subjects. Performance differences among types of peripheral defocus may result from magnification effects and intrinsic peripheral refraction. These results highlight the importance of understanding the effects of induced peripheral errors by myopia
- PublicationOpen AccessIn vivo SS-OCT imaging of crystalline lens suturesGupta, A.; Ruminski, D.; Jimenez Villar, A.; Duarte Toledo, R.; Manzanera Román, Salvador; Panezai, S.; Mompeán Esteban, Juan; Artal Soriano, Pablo; Grulkowski, I.; Electromagnetismo y Electrónica
- PublicationRestrictedMechanical evaluation of the resistance of Theraband CLX(PubMed, Human Kinetic Journals, 2023-01-27) Martín San Agustín, Rodrigo; Arenas Dalla Vecchia, Aurelio; Cánovas Ambit, Germán; Medina Mirapeix, Francesc; Gacto Sánchez, Mariano L.; Electromagnetismo y ElectrónicaContext: Calculating the resistance provided by elastic resistance is essential with the aim of adjusting the load and controlling the progression of the exercises in programs using elastic resistance. This study aimed (1) to establish a model of the force elongation for CLX bands; (2) to examine whether these models are altered by different aspects of band elongation: the phase of elongation and shortening (concentric and eccentric phases), the elongation speed, and the initial resting length; and (3) to determine the resistance value for 100% of elongation in each color and to compare it with the values reported by Theraband. Design: Cross-sectional. Methods: Ten CLX bands of each color were elongated by 2 experienced researchers to establish their elongation force curves in series of 10 repetitions per band using a Smith machine for an anchor, examining whether elongation force models were affected by elongation and shortening phases using one 4-loop CLX band stretched to 100% and at 0.50 m/s, elongation speed stretching two 4-loop CLX bands at 0.50 m/s and at 0.70 m/s, and different starting lengths using 3 CLX bands (2, 3, and 4 loops) stretched at 0.50 m/s. Results: No differences were found in the comparisons between phases, speeds, or different start lengths (mean errors ranged from 0.01 [0.07 N] for the blue band to 2.97 [0.94 N] for the gold band). Our values were higher than the reference values provided by Theraband for all colors, ranging from 2.3% to 33.1%. Conclusions: Our findings show that the values provided by the brand underestimate the resistance provided by CLX bands. To solve this, regression equations are provided so professionals can calculate the resistance of CLX bands based on their elongation. In addition, these models are not influenced by the phase of elongation and shortening, the elongation speed, and the initial resting length.
- PublicationOpen AccessMethodology for Energy Optimization in Wastewater Treatment Plants. Phase I: Control of the Best Operating Conditions(MDPI, 2019-07-18) Lozano Avilés, Ana Belén; Del Cerro Velazquez, Francisco; Llorens Pascual del Riquelme, Mercedes; Ingeniería Química; Electromagnetismo y ElectrónicaMost purification systems work correctly from the point of view of water quality; purification, like any industrial process, must also be carried out efficiently with a minimization of costs. The overall project examined the potential benefits of using a recommended methodology for process evaluation and energy optimization in the aeration stage of activated sludge in the biological reactor at wastewater treatment plants (WWTP), which accounts for more than 44% of total operating costs. This energy control methodology encompasses the process, the installation and the control system. These three phases are examined in separate articles to make it easier to guide the user in the arduous task of optimizing energy efficiency of the WWTP from start to finish. This article focuses on Phase I of the methodology, the stage in charge of selecting the correct variables to control the best process conditions in the activated sludge system of the WWTP. Operating conditions that are a function of the recommended sludge age are influenced by exogenous factors such as temperature. The implementation of a real-time control system of the selected process variables, adapted to the needs, achieves reductions in the overall energy consumption of the installation, in this phase alone, of more than 15%, by reducing the oxygen requirements of the system and the recirculation ratios.
- PublicationRestrictedOn the thermal performance of flat and cavity receivers for a parabolic dish concentrator and low/medium temperatures(Elsevier, 2020-09) López Espinosa, Ovidio; Baños Torrico, Alfonso; Arenas Dalla Vecchia, Aurelio; Electromagnetismo y Electrónica; Informática y SistemasApplication of parabolic dish collector systems working in a range of low/medium temperatures is of great importance in industrial practice. In this work, a thermal efficiency analysis will be performed for different receivers such as a flat-plate receiver and a cavity receiver (with and without a glass cover). Most of the previous receivers analyses found in the literature have been performed for applications with high temperatures. Moreover, a detailed analysis including losses such as reradiation, natural and forced convection, and conduc tion, have been performed, developing new correlations for natural and forced convention. The obtained results are discussed in detail, obtaining a significant increasing of efficiency of the cavity receivers against the flat-plat receiver with much less working temperatures: up to 20% for the covered cavity receiver in comparison with the flat-plate receiver, with a temperature reduction at the receiver of more than 450 °C
- PublicationRestrictedReceptor solar de cavidad para colector de disco parabólico(OEPM, 2023-04-26) Baños Torrico, Alfonso; Arenas Dalla Vecchia, Aurelio; López Espinosa, Ovidio; Electromagnetismo y Electrónica; Informática y SistemasReceptor solar para colector de disco parabólico. Consiste en un absorbedor cilíndrico con cavidad que, estando situado en el punto focal de la parábola, capta la radiación solar reflejada desde el colector. Por la parte más caliente del receptor entra un fluido caloportador que recorre el receptor a lo largo de un circuito en forma de espiral practicado en el interior del mismo. El fluido, finalmente, sale del receptor a una temperatura considerablemente más alta y es conducido al intercambiador de calor de una caldera para generar vapor. El circuito en espiral obliga al fluido a circular a velocidad constante en todo su recorrido, evitando zonas de estancamiento del fluido que provocarían puntos calientes donde pueden generarse gases por evaporación del fluido. Estos gases podrían provocar golpes de ariete en el interior del receptor y por las tuberías de la instalación y poner en riesgo su integridad mecánica.
- PublicationRestrictedReset-and-hold control of systems with time delay(IEEE, 2022) Sáez Pérez, José F.; Baños Torrico, Alfonso; Arenas Dalla Vecchia, Aurelio; Electromagnetismo y Electrónica; Informática y Sistemas— Reset control is a kind of hybrid control which is ca pable of overcoming fundamental limitations on the performance intrinsic to linear time invariant (LTI) systems. In this work, we develop a novel parallel control strategy for first order LTI plants with delay based on the proportional-integral plus Clegg integrator (PI+CI) controller, a hybrid extension of the proportional-integral (PI) controller, augmented with a mechanism for keeping its state constant during a given interval of time (reset-and-hold strategy). This strategy is capable of producing an approximation of a flat response which greatly improves the performance in compari son with non-hybrid linear strategies, extending previous results developed for first order systems without delay. An example is developed that showcases the possibilities of this new approach.
PublicationOpen AccessThe Low-Altitude Ionosphere of the Ice Giant PlanetsMolina-Cuberos, Gregorio José; Electromagnetismo y Electrónica- PublicationOpen AccessTwo-dimensional peripheral refraction and retinal image quality in orthoqueratology lens wearers(2020) Zhenghua, L.; Duarte Toledo, R.; Manzanera Román, Salvador; Lan, W.; Artal Soriano, Pablo; Yang, Z.; Electromagnetismo y Electrónica
- PublicationOpen AccessValidity and realiability of a new optoelectronic system for measuring active range of motion of upper limb joints in asymptomatic and symptomatic subjects(MDPI, 2019-11-02) Martín San Agustín, Rodrigo; García Vidal, José A.; Cánovas Ambit, Germán; Arenas Dalla Vecchia, Aurelio; López Nicolás, Manuel; Medina Mirapeix, Francesc; Electromagnetismo y ElectrónicaThe aim of this study was to evaluate the validity of the Veloflex infrared dynamic angle-meter (Veloflex-IDA) and the intra- and inter-rater reliability when measuring the ranges of motion (ROMs) of the upper limb joints. Thirty-five healthy and 20 symptomatic participants were evaluated. Twelve upper limb movements were measured in two sessions with the Veloflex-IDA, which is a device composed of a camera that tracks the trajectory of retro-reflective markers. In addition, a goniometer was used in the first session to evaluate concurrent validity. Validity and agreement were evaluated by Pearson correlation coefficient (r) and Bland-Altmann plots. Intra- and inter-rater reliability were evaluated using intra-class correlation (ICC), standard error of measurement (SEM), and minimal detectable change (MDC). Both instruments showed excellent correlation for all movements (r range from 0.992 to 0.999). The intra- and inter-rater reliability were excellent (ICC range from 0.95 to 0.99 and 0.90 to 0.98, respectively). Intra-rater reliability showed SEMs <1.38% and <5.19% and inter-rater reliability SEMs <2.26% and <5.22% for asymptomatic and symptomatic, respectively. Veloflex-IDA is a valid and reliable alternative to measure the upper limb joints' ROM and it can be used in clinical practice and research after basic training.
- PublicationOpen AccessValidity and reliability of Veloflex to measure active cervical range of motion in healthy participants(Peer J, 2021-04-05) Cánovas Ambit, Germán; García Vidal, José A.; Martín San Agustín, Rodrigo; Arenas Dalla Vecchia, Aurelio; Sánchez Barbadora, Mariana; Medina Mirapeix, Francesc; Electromagnetismo y ElectrónicaBackground Neck pain has a high annual incidence and decreases the cervical active range of motion (ROM). Clinicians use various methods to evaluate cervical range of motion (CROM) that some of them have also been proposed to give instant feedback. Accordingly, this study aimed to examine the validity and reliability of Veloflex (VF) to measure the CROM by comparison with the cervical range of motion (CROM) device, and to examine their test-retest reliability. Methods Thirty-eight healthy and 20 symptomatic participants were evaluated. Cervical flexion-extension, side bending, and rotations were tested in two sessions, first by the CROM and VF and in the second only with the VF. To evaluate the concurrent validity and agreement between CROM and VF, Pearson correlation coefficient ( r ) and Bland–Altmann plots were used. Reliability were evaluated using intra-class correlation (ICC), standard error of measurement (SEM) and minimal detectable change (MDC). Results CROM and VF showed excellent correlation for all movements ( r > 0.960). Both devices provided small mean ‘bias’ (≤1.29%) in all movements regarding CROM measures. The intra-rater and inter-rater reliability of the VF was excellent (ICC > 0.98). SEMs ranging from 0.72% to 2.38% and the MDC ranging from 1.22° to 2.60° in all participants. The results support the validity and reliability of VF to measure CROM. For its use, with a basic training is enough to get reliable measurements.
- PublicationOpen AccessVision with pulsed infrared light is mediated by nonlinear optical processes(2020) Manzanera Román, Salvador; Sola Martínez, Daniel; Khalifa, N.; Artal Soriano, Pablo; Electromagnetismo y ElectrónicaWhen the eye is exposed to pulsed infrared (IR) light, it is perceived as visible of the corresponding half wavelength. Previous studies have reported evidence that this is due to a non-linear two-photon absorption process. We have carried out a study which provides additional support to this nonlinear hypothesis. To this end, we have measured the spectral sensitivity at 2 different pulse repetition rates and have developed a theoretical model to account for the experimental observations. This model predicts a ratio between the minimum powers needed to detect the visual stimulus at the 2 pulse repetition rates employed of 0.45 if the stimulus were detected through a nonlinear effect and 1 if it were caused by a linear effect as in normal vision. The value experimentally found was 0.52 ± 0.07, which supports the hypothesis of a nonlinear origin of the two-photon vision phenomena.