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Efficient online generation of fuzzy measures via aggregation functions
No full textDiscrete fuzzy integrals (F-integrals) are fusion functions that leverage discrete fuzzy measures to capture interactions within the data. However, their scalability is often limited by the computational overhead of evaluating the measure across the entire measurable space. This paper introduces an efficient online approach for generating fuzzy measures using aggregation functions. The online methodology allows to calculate the F-integral alongside the fuzzy measure without increasing its asymptotic complexity and without requiring previous calculations. The role of the aggregation functions is to establish the properties of the generated measure. To this end, we define and study non-conjunctive aggregation functions, designed to prevent vanishing measures and ensure that the resulting measures retain meaningful and useful properties. In addition the methodology includes an optimizable component, enabling the learning of fuzzy measures and therefore the use of F-Integrals in learning environments. A complexity analysis confirms the method's efficiency, and experiments on supervised classification tasks demonstrate its practical utility.This work was supported in part by Oracle Cloud credits and related resources provided by the Oracle Strategic Partner & Innovation program. Open access funding provided by Universidad Pública de Navarra. Xabier Gonzalez-Garcia's and Humberto Bustince's research has been supported by the PID2022-136627NB-I00 project funded by MCIN/AEI/10.13039/501100011033/FEDER, UE. L'ubomíra Horanská has been supported by the project VEGA 1/0239/24 and VEGA
1/0318/25. Thanks to Dr. Javier Fumanal-Idocín for his support with the Ex-Fuzzy library
Paradoxes of co-opting women into leadership positions: disparities in their identities as labour leaders in Spain
No full textThis article examines how women trade unionists in Spain construct and negotiate their leadership identities within organisations historically shaped by masculine norms. Drawing on a qualitative study based on 25 semi-structured interviews with women who currently hold or have held positions of responsibility within the main trade unions in the Basque Country or as union delegates representing them in various contexts, it explores the meanings attributed to leadership and the trajectories to power as narratives that underpin political identity. From a theoretical approach combining social constructionism and feminist poststructuralism, the article proposes a discursive reading of leadership as an unstable, situated and contested identity. The analysis identifies two key dynamics. Firstly, co-optation mechanisms enable access to power but also generate ambivalence and identity gaps that condition recognition while opening spaces for resistance and alternative forms of leadership. Secondly, when leadership is not linked to feminist objectives, women's identification as leaders becomes more fragile and less politicised. Rather than consolidating itself as a fixed identity, leadership is often exercised as a contextual and deliberative strategy that challenges normative frameworks of authority. The study offers a situated but potentially transferable perspective on the discursive construction of leadership in gendered terms, highlighting precarious yet significant forms of female agency in masculinised contexts and providing tools for rethinking their possibilities for re-signification.This work was supported by Emakunde – Basque Institute for Women, Government of the Basque Country (Spain) [Grant number Resolution of 5 July 2022]. Open access funding provided by Universidad Pública de Navarra
A systematic literature review of emergency communications assisted by unnamed aerial vehicles
No full textReliable communication systems are critical during emergency scenarios such as floods, earthquakes, fires, and hurricanes to ensure timely information exchange and minimize damage. However, traditional communication infrastructure is often severely compromised during such events. Unmanned Aerial Vehicles (UAVs) have emerged as a promising solution to deploy temporary communication networks in disaster-affected areas. Although several studies have proposed architectures and deployment strategies for UAV-assisted communication, and reviews have addressed their potential, comprehensive discussions on protocol configurations, architectural considerations, and deployment parameter optimization remain limited. This paper presents a systematic literature review covering the period from 2014 to 2024, focusing on the use of UAVs in emergency communication systems. The reviewed articles are classified into a structured taxonomy according to the emergency scenario, UAV role, communication architecture, and protocol layer. Additionally, common communication parameters optimized for deployment, such as coverage and throughput, and the optimization methods employed, including heuristic and artificial intelligence techniques, are identified. The findings reveal that UAVs are predominantly deployed as aerial base stations for large-scale dynamic disasters, with protocol development focusing mainly on the physical, data link, and network layers. However, the lack of standardized deployment guidelines and limited real-world experimentation highlight a significant research gap. This review underscores the need for benchmark methodologies to support the effective and comparable deployment of UAV-assisted emergency communication systems.The authors thank Tecnologico de Monterrey for its financial support. Isaac Lopez-Villegas and Erick Axel Martinez-Rios are funded by Secretaria de Ciencia, Humanidades, Tecnologia e Innovacion (SECIHTI) (scholarships 162978 and 1010770, respectively)
Precise and low-cost computationally efficient method for operational modal analysis in wind turbines
No full textStructural Health Monitoring of wind turbines using Operational Modal Analysis techniques has become increasingly important in the wind industry. This importance is underscored by the fact that many installed wind farms are nearing the end of their operational lifespan and require life extension strategies that ensure safe operation. However, most existing techniques in the state of the art are either imprecise or necessitate complex calculations and high computational costs. These limitations often require extensive data extraction for external processing, the use of complex processors, and the engagement of external services for data analysis, posing significant challenges for wind farm owners. This paper presents an Operational Modal Analysis algorithm designed for Structural Health Monitoring of wind turbines, addressing the aforementioned issues. The proposed algorithm is highly computationally efficient, allowing for implementation on a low-cost electronic node that can autonomously analyze the structural health of the wind turbine with high precision. To achieve this, the algorithm employs a combination of techniques, some of which are novel, such as the modeling of modes and harmonic elimination using linear Kalman filters. Other techniques, such as the Random Decrement Technique and the Ibrahim Time Domain, are well-established in literature. However, the specific combination of these techniques as presented in this paper is also a novelty. All these techniques involve simple calculations, resulting in an efficient algorithm with low computational cost. Moreover, this paper validates the algorithm using both synthetic signals from OpenFAST and real signals from wind turbines. The results are highly satisfactory, outperforming leading techniques in this context and confirming the algorithm's precision. Notably, the algorithm excels in damping estimation, a challenging aspect of Operational Modal Analysis applied to wind turbines, for which no existing Operational Modal Analysis techniques provide precise estimates. In conclusion, the algorithm presented in this paper offers a precise, efficient, and low-cost solution for Structural Health Monitoring of wind turbines, eliminating the need for extensive data processing and external analysis, thereby simplifying and improving the maintenance and operation of wind farms.This paper has been supported by the Spanish Research Agency, and the EU/PTR Next Generation Funds under grants PID2019-107258RB-C32, TED2021-131052B-C21, and PID2022-138491OB-C32. I. Vilella is supported by a grant for Industrial Doctorates 2021 from the Government of Navarre. Open access funding provided by Universidad Pública de Navarra
Compact fluorine-doped multimode fiber sensor for refractometry in the visible spectrum
No full textWe present the design and experimental validation of a compact refractive index sensor based on a multimodefluorine-doped-multimode (MFM) fiber structure. The sensor exploits modal interference eects in the visible spectrum by incorporating a FG105LCA multimode fiber segment with a fluorine-doped cladding. By varying the length and diameter of the central fiber segment, we achieve a significant shift in
the attenuation peaks, enabling a high-resolution and compact design. Experimental results demonstrate a maximum sensitivity of 137.07 nm/RIU and a sensitivity of the wavelength shift to the refractive index up to 41.66 nm/RIU. Furthermore, a miniaturized reflective configuration using a 15 mm segment is proposed, oering both performance and integration advantages.This work was supported by Open Access funding provided by the Universidad Pública de Navarra
Choquet-inspired aggregation functions
No full textIn this work, we propose a new family of aggregation functions inspired by the well-known Choquet integral. To build these functions, we replace the measure in the definition of the Choquet integral by an appropriate function. We study the properties of these aggregation functions and explore the relations with some other common aggregation functions such as order statistics and overlap and grouping functions.H. Bustince, J. Fernandez and G.P. Dimuro are partially supported by research project PID2022-136627NB-I00, Spain ( MCIN/AEI/10.13039/501100011033/ FEDER, UE ). G.P. Dimuro also thanks FAPERGS (Proc. 23/2551-0000126-8 ) and CNPq (Proc. 304118/2023-0 , 407206/2023-0 ). R. Mesiar is supported by Project VEGA 1/0036/23
Coffee and cocoa by-products as valuable sources of bioactive compounds: the influence of ethanol on extraction
No full textCocoa and coffee are two of the world’s most important crops. Therefore, their by-products are generated in large quantities. This work proposes a simple method for the valorization of these residues by obtaining phenolic compounds and melanoidins by solid–liquid extraction using different hydroalcoholic solutions as extracting solvents (0, 25, 50, 75, 100% ethanol). Extracts of both by-products presented the highest antioxidant capacity and total phenolic and melanoidin content when using 50–75% ethanol in the solvent. Among all the extracts, those obtained from spent coffee grounds at 75% ethanol showed the highest concentrations of total phenolic compounds (13.5 ± 1.3 mmol gallic acid equivalents/g dry matter) and melanoidins (244.4 ± 20.1 mg/g dry matter). Moreover, the sun protection factor values of the coffee extracts obtained with 50 and 75% of ethanol as extraction solvent (7.8 ± 0.9 and 8.5 ± 0.7, respectively) showed their potential for use in the cosmetic sector. The most important phenolic compounds identified in the coffee by-products extracts were phenolic acids, and most of them were found in higher concentration in extracts obtained with lower percentages of ethanol (0–25%). Protocatechuic acid was the most abundant phenolic in cocoa extracts, with concentrations ranging from 18.49 ± 2.29 to 235.35 ± 5.55 µg/g dry matter, followed by 4-hydroxybenzoic acid, (-)-epicatechin and (+)-catechin. Esculetin was found in both coffee and cocoa extracts, which had not been reported to date in these residues. In summary, the use of 75% ethanol as an extraction solvent seems a good strategy to obtain extracts rich in phenolic compounds from food by-products rich in melanoidins, such as coffee and cocoa by-products. The high antioxidant potential of these extracts makes them of great interest for the cosmetic and nutraceutical industries.This research was financially supported by the grant PID2021-122675OB-C21 founded by MICIU/AEI/10.13039/501100011033 and, as appropriate, by 'ERDF A way of making Europe', by 'ERDF/EU', by the 'European Union'. The acquisition of the HPLC-ESI-QTRAP equipment was possible thanks to the co-financing of the Ministry of Science, Innovation and Universities of the Spanish Government, the FEDER program of the European Union (Project: EQC2018-005202-P), and the Universidad Pública de Navarra
Nursing scope of practice determinants in hospitalization units
No full textLa presente tesis doctoral se enmarca dentro del área temática de recursos humanos en el ámbito de la salud, más concretamente en el área de enfermería. Se justifica en la dificultad actual de dotar de enfermeras a los servicios de salud, ante la situación de crecientes demandas de los sistemas sanitarios por parte de la población y la situación de escasez de profesionales a nivel mundial. Las enfermeras son uno de los recursos más numerosos y costosos para la provisión de los servicios de salud por lo que una de las prioridades en materia de gestión es perseguir su eficiencia.
A partir de ahí, se planteó medir en qué grado las enfermeras empleaban su tiempo en realizar aquellas actividades para las que habían sido formadas, lo que se conoce como el alcance de práctica de las enfermeras. Para ello, se adaptó, tradujo y validó al español el Cuestionario del Alcance de Práctica de las Enfermeras, utilizado a nivel internacional. Mediante un análisis secuencial exploratorio con una muestra de 310 enfermeras, pertenecientes a los tres hospitales de la red pública de Navarra, y tras comprobar las propiedades psicométricas, se obtuvo la versión española del Cuestionario del Alcance de Práctica de las Enfermeras que mostró buena validez y fiabilidad adaptado a nuestro contexto.
Posteriormente, y como principal objetivo de esta investigación, se identificaron los determinantes del alcance de práctica de las enfermeras de hospitalización médico-quirúrgica y unidades de cuidados intensivos. Se realizó un diseño observacional de tipo transversal y con el empleo de modelos lineales mixtos se estableció la relación de las características de las enfermeras, tanto personales como laborales, con su alcance de práctica. De igual forma, se estimó el efecto adicional de pertenecer o no a una unidad de cuidados intensivos. Las características capaces de predecir de manera positiva el alcance de práctica de las enfermeras fueron la demanda psicológica, el entorno de práctica y la necesidad de autodesarrollo, mientras que la ambigüedad del rol demostró ser un determinante para que las enfermeras implementen menos su alcance de práctica.
Con todos estos resultados, se ha generado una herramienta que puede ser de utilidad para gestionar los recursos de enfermería de manera más eficiente. La versión española del Cuestionario del Alcance de Práctica de las Enfermeras proporciona una evidencia sólida que ayudará a proponer medidas no necesariamente relacionadas con un aumento de personal, sino dirigidas a mejorar las condiciones de las enfermeras como mejorar los entornos de práctica, incentivar los programas de desarrollo y disminuir aquellas situaciones laborales que puedan generar ambigüedad o confusión en las tareas. Es decir, este estudio sirve de punto de partida para proponer estrategias de gestión que favorezcan que las enfermeras sean más eficientes para el sistema de salud, incidiendo en medidas que afecten a los determinantes que hacen que estas desarrollen su alcance de práctica.The following lines present a doctoral dissertation that is framed within the topic area of Nursing Resource Management. The justification for this thesis is the current difficulty in providing nurses due to increasing demands for health services and a shortage of nursing professionals worldwide. Efficiency in nursing staff is a top priority in health service management due to its high cost and large number of staff.
In order to measure nurses' scope of practice, or in other words, the extent to which nurses spend their time performing the activities for which they are professionally trained, we first adapted, translated and validated the nurses' scope of practice questionnaire into Spanish. For this purpose, we conducted an exploratory sequential analysis. We tested the psychometric properties of a scope of practice questionnaire for nurses with 310 nurses from the three main hospitals in the public health system in Navarra, and obtained a questionnaire with good validity and reliability adapted to our context. Subsequently, and as the main objective of this research, a cross-sectional observational design was used to analyse the determinants of the scope of practice of nurses in medical-surgical hospitalisation and intensive care units. Linear mixed models were used to establish the relationship between nurses' personal and occupational characteristics and their scope of practice. The additional effect of belonging to an intensive care unit was also estimated. Psychological demand, practice environment, and growth need strength were found to positively predict nurses' scope of practice, while role ambiguity was shown to be a factor that reduces nurses' implementation of their scope of practice. All these findings have created a tool that can be useful in managing nursing resources more efficiently, providing solid evidence to help propose measures not necessarily related to increasing staffing levels, but aimed at improving conditions, such as improving the practice environment, promoting development programs, and reducing those work situations that may lead to ambiguity or confusion of tasks. This study can therefore be used as a starting point for proposing management strategies that help nurses to be more efficient for the system, focusing on measures that affect the determinants that lead nurses to develop their scope of practice to a greater extent.Tesis financiada a través de la Conferencia Nacional de Decanos y Decanas de Enfermería (CNDE), como resultado del proyecto de investigación de la Convocatoria de Proyectos de Investigación 2017.Programa de Doctorado en Ciencias de la Salud (RD 99/2011)Osasun Zientzietako Doktoretza Programa (ED 99/2011
Integrales difusas discretas y sus aplicaciones
No full textThis doctoral thesis introduces new generalizations of discrete fuzzy integrals with three distinct applications. We introduce four new families of discrete fuzzy integrals, including the d-XChoquet integral, the dCF -integrals, and the extended families of discrete
Choquet and Sugeno integrals. These new generalizations are designed to provide better flexibility and performance in applications. In addition, we investigate the theoretical properties of these new integral generalizations, such as monotonicity. Furthermore,
extensive experiments are conducted to compare the performance of the new, proposed, integrals with existing ones in three distinct applications: in classification, decision-making analysis, and in brain signal processing. The results demonstrate that
the proposed generalizations perform better than other discrete fuzzy integrals in most applications.Programa de Doctorado en Ciencias y Tecnologías Industriales (RD 99/2011)Industria Zientzietako eta Teknologietako Doktoretza Programa (ED 99/2011
Towards a heat-resistant tethered micro-aerial vehicle for structure fire sensing
No full textThe collapse of structures during firefighter intervention is one of the greatest risks that firefighters must face when entering buildings. To reduce these risks, situational awareness is key. Although many advances have already been developed in wildland and outdoor fires, there is still room for improvement in structure fires. The development of a heat-resistant micro-aerial vehicle for indoor fires poses a series of challenges such as component cooling, battery management, and protection from impacts. In this paper, a heat-resistant tethered micro-aerial vehicle is designed, modeled through thermal analysis, and successfully tested in real-world conditions. This platform has been equipped with a micro-sized thermal sensing camera and first-person-view (FPV) camera, optimized for thermal management, to allow for situational awareness in structure fires.This work has been supported in part by the Government of Navarre (Departamento de Desarrollo Económico) under the research grants 0011-1411-2024-000038-H2DRON, and 0011-1365-2023-000087-SIMB-IA. Paper submitted for review in December 2024