idUS. Depósito de Investigación Universidad de Sevilla
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Integer fuzzy production possibility set and slack-based integer fuzzy DEA model with hybrid extension
No full textThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.This paper introduces an axiomatic approach to integer fuzzy DEA for efficiency assessment. To this end, we model the information by means of a new class of trapezoidal integer fuzzy numbers, also considering a hybrid scenario. Using integer fuzzy arithmetic and partial orders, we propose a non-oriented slacks-based integer fuzzy DEA approach that allows computing inefficiency scores as well as efficient fuzzy targets. The proposed approach involves two phases, with the phase II model required to distinguish between efficient, weakly efficient, and inefficient units. Several numerical examples are provided to illustrate and explain the new concepts and the proposed approach
Funcionalidad de la hoja del olivo y sus compuestos fenólicos en la respuesta inmunoinflamatoria articular
No full textIntroducción: La inflamación es uno de los principales aspectos en común entre la gran mayoría de las enfermedades crónicas. Esto se debe a la descompensación de los mecanismos reguladores de la misma, y al envejecimiento junto a su fenotipo proinflamatorio crónico progresivo, o inflammaging. La necesidad de buscar nuevos tratamientos para el abordaje de estas enfermedades crónicas se ve impulsada por la gran variedad de efectos adversos y desventajas que presenta la actual línea de tratamiento. Debido a esto, surge un gran interés entorno a la investigación de ciertos elementos utilizados en la medicina tradicional, entre los que encontramos la hoja de olivo. Objetivos: Evaluar el papel de los compuestos fenólicos presentes en la hoja de olivo y sus metabolitos en la modulación de la respuesta inmunoinflamatoria así como el estudio de las posibles vías de señalización implicadas. Materiales y métodos: El ensayo de capacidad antioxidante de los compuestos se realizó por el método ABTS. El estudio de viabilidad celular se realizó siguiendo el método del MTT. La cuantificación de la producción de las citoquinas proinflamatorias IL-6 y TNFα se llevó a cabo mediante el método ELISA. El estudio de la modulación de las vías celulares NFB y Nrf2/HO-1, relacionadas con la inflamación, se hizo mediante la técnica de Western blot. Resultados: El pretratamiento con las concentraciones más altas de OLE y los compuestos fenólicos presentes en la hoja de olivo provocó una disminución significativa en la producción de IL-6 y mostraron una tendencia a la disminución de la producción de TNFα. Tras el pretratamiento con OLE, se observó activación del eje Nrf2/HO-1 y una tendencia en la protección de IBα. Conclusión: El OLE junto a algunos de los compuestos fenólicos presentes en la hoja de olivo presenta actividad antiinflamatoria al reducir significativamente la producción de IL-6. Esto se vio acompañado de una activación del eje Nrf2/HO-1 y una tendencia de la protección del IBα.Grado en Biomedicina Básica y Experimenta
A High-Level-of-Assurance EUDI Wallet with a Remote WSCD Supporting Biometrics and Passkeys
No full textThe European Digital Identity (EUDI) Wallet is a user-controlled digital environment that is being developed to be used by all citizens of the European Union. The Architecture and Reference Framework (ARF) of the EUDI Wallet is a set of specifications designed to ensure their interoperability and security. Among specifications, a Wallet Secure Cryptographic Device (WSCD) with a high Level of Assurance must be used. A high LoA is achieved through the multifactor authentication of the Wallet User and the use of secure hardware for implementing the needed cryptographic and biometric algorithms. Also, EUDI Wallets should include a functionality to generate and manage user-chosen pseudonyms,
to authenticate Users when accessing online services. This paper describes a high LoA EUDI Wallet using a remote WSCD, which is the most inclusive, userfriendly and scalable type of WSCD. User authentication is done through something you know (a password), something you have (a smartphone), and who you are (with facial biometrics). As secure hardware for the remote WSCD, we use an Intel SGX enclave. The WSCD allows the generation and management of Passkeys, which are a kind of pseudonyms following the W3C WebAuthn specification. A demonstrator has been developed using a Samsung Galaxy A52 as User device with the Wallet Instance, and a laptop with an Intel® Core ™ i7-10750H at 2.60 GHz and 16 GB RAM with Ubuntu 20.04.6 LTS, Intel SGX1 and disabled hyper-threading to implement the remote WSCD. The experimental results show that the WSCD needs 128MB of RAM and takes 374.2 ms to be bound to a User, 375.2 ms to authenticate the User and create a new Passkey, and 373.8 ms to authenticate the User and sign with an already existing Passkey
An inf-sup stable phase-field formulation for fracture of thermo-responsive hydrogels: Isotropic and transversely isotropic material models
No full textThis investigation presents a comprehensive phase-field formulation for fracture analysis of thermo-responsive hydrogels, encompassing both isotropic and transversely isotropic material models within an integrated thermo-chemo-mechanical framework. The proposed numerical approach addresses computational challenges through a mixed variational formulation that ensures inf-sup stability while maintaining robust fracture simulation capabilities. The finite element implementation employs quadratic interpolation functions for the displacement field and linear shape functions for the chemical potential (fluid pressure), temperature, and fracture fields. This formulation is implemented as a user-element subroutine UEL in ABAQUS, utilizing a Q2Q1Q1Q1 finite element formulation. The validation strategy comprises two key investigations. First, a comparative analysis against the foundational work of Böger et al. (2017), pinpoints the capacity of the current formulation to achieve numerical stability while accurately capturing fracture limit states across varying temperature conditions. Second, the methodology is applied to simulate complex material behavior through the analysis of pre-notched specimens under combined swelling and mechanical loading conditions. This thorough assessment provides valuable insights into the coupled chemical and mechanical responses of thermo-responsive hydrogels, demonstrating the ability of the proposed formulation in simulating these advanced materials
Electrochemical tailoring of graphite properties for tunable catalytic selectivity of glucose conversion to 5-hydroxymethylfurfural
No full textThis study presents a novel approach for boosting the selectivity of 5-hydroxymethylfurfural (HMF) production from glucose through electrochemical modification of graphite materials. Three distinct graphitic substrates were subjected to controlled electrochemical treatments utilizing sodium sulfate or phosphoric acid as electrolytes. The process expanded the graphite particles/pieces and introduced oxygenated functional groups to the exposed surfaces while preserving the structural integrity of the bulk material. The resulting modifications influenced the type and quantity of Lewis and Brønsted acidic sites, providing exhaustive control over reaction pathways leading to HMF. This electrochemically modified graphite demonstrated superior tunability compared to traditional metal-based catalysts, enabling dynamic optimization of reaction conditions for enhanced HMF yield. The controlled introduction of functional groups facilitated the tailoring of active sites, significantly impacting the kinetics of glucose conversion and achieving HMF selectivity up to 95%. This level of precision in controlling catalytic properties is essential for maximizing HMF yield while minimizing undesired by-product formation, addressing a critical challenge in HMF production
Red torulene from yeast: Isolation, characterization, bioprocess development, and its underexplored pioneering application as a natural food colorant
No full textTorulene, a red carotenoid produced by Rhodotorula species, has gained significant attention for its vibrant color and potential health benefits. However, while several reviews have explored its properties, there remains a lack of research on its practical applications across diverse industries. This study aims to fill this gap by isolating and characterizing a novel R. mucilaginosa strain (PUCV 645) from Chile, with a focus on evaluating the use of edible oils as extraction agents for the recovery of torulene-rich extracts (TRE). The COSMO-SAC predictive model was employed to explain the interactions involved in the green extraction process. Additionally, TRE has two innovative applications: its use as a natural food colorant in pasta and as a component in colored vegan mayonnaise, where it is combined with residual aquafaba as a potential egg replacer. Through molecular identification, phylogenetic analysis, and carotenoid characterization, this work provides the first comprehensive exploration of R. mucilaginosa PUCV 645's potential for food industrial applications. The findings highlight the promise of TRE as a sustainable, natural alternative in food manufacturing, paving the way for its integration into the food industry. This study also contributes to the understanding torulene's versatility and potential market applications
Solving an Unrelated Parallel Machines Scheduling Problem with machine- and job-dependent setups and precedence constraints considering Support Machines
No full textSingle-stage production planning problems are common in the academic literature and in real-world environments. One of the least studied scenarios in the literature for this environment is that with Unrelated Parallel Machines. In this work, this type of problem is inspired by a real station within the wind tower production process. The problem presents characteristics that have already been studied, such as mandatory precedences and setup times that depend on the machine and the job. However, a new and real feature is presented: the existence of “support machines”, which are machines that can continue to work but cannot complete jobs due to reduced capacity for some operational reason. In this case, instead of abandoning their work, support machines can still be used to assist other machines by performing partial jobs before handing them over to full-capacity machines for completion. This innovative concept of support machines, never before presented in this context of production planning, introduces a unique approach to dealing with reduced-capacity machines without sacrificing their operational potential. A Mixed-Integer Linear Programming (MILP) model is formulated to mathematically represent this problem.
This work explores the impact of these support machines on production planning. For this purpose, Tabu Search and Simulated Annealing metaheuristics have been adapted for their solution, and a novel Constructive Heuristic has been developed based on the real and manual process currently performed in the aforementioned factory. These three algorithms are run and compared on a real database in order to minimise the makespan. Their analysis shows that although the use of support machines generally gives positive results, an improvement is not achieved in all cases. Furthermore, contrary to what might be expected, the use of full-capacity machines in the role of support machines sometimes improves completion times
Los orígenes del ejército moderno en el reino de Castilla, siglos XIV-XV
No full textLa tesis doctoral titulada “Los orígenes del Ejército Moderno en el reino de Castilla, siglos XIV-XV” tiene por objeto mejorar el conocimiento histórico de la hueste castellana bajomedieval en su evolución hacia el ejército Moderno, mediante el estudio y análisis de las transformaciones en su organización militar; de sus planeamientos estratégicos y sus actuaciones tácticas en conflictos armados internos y externos; de sus necesidades, capacidades y limitaciones logísticas; y la incidencia de dichos aspectos en la ideología y actitudes, y su repercusión material y mental en la sociedad de la época, haciendo especial hincapié en frontera con Granada.
En definitiva, desvelar los factores que hicieron posible a una hueste plenamente medieval como la castellana, sentar las bases de lo que con el tiempo, llegaría a ser el Ejército Moderno, que tanta fama alcanzó en siglos posteriores.
En cuanto a la estructura de la tesis, tras presentar las diferentes corrientes historiográficas y el preceptivo estado de la cuestión -Capítulos 1 y 2-, se expone el método de investigación usado para el análisis histórico de las acciones bélicas, fruto de la adaptación del método militar empleado para la resolución del problema táctico-logístico -Capítulo 3-. Tras un breve análisis de las fuentes -Capítulo 4-, se aborda la esencia de la tesis a través del estudio de la organización militar terrestre bajomedieval castellana -Capítulo 5-, sus tácticas -Capítulo 6-, y la logística -Capítulo 7-, para acabar con la resolución de las cuestiones planteadas a través de las conclusiones -Capítulo 8-