Computing the phase diagram of binary mixtures: a patchy particle case study

We investigate the phase behaviour of 2D mixtures of bi-functional and three-functional patchy particles and 3D mixtures of bi-functional and tetra-functional patchy particles by means of Monte Carlo simulations and Wertheim theory. We start by computing the critical points of the pure systems and then we investigate how the critical parameters change upon lowering the temperature. We extend the Successive Umbrella Sampling method to mixtures to make it possible to extract information about the phase behaviour of the system at a fixed temperature for the whole range of densities and compositions of interest.Comment: 13 pages, 13 figure

La conquista de Antequera, con la Leyenda de la Peña de los Enamorados

Copia digital : Diputación de Málaga. Biblioteca Canovas del Castillo, 201

Natural frequencies for bending vibrations of Timoshenko cracked beams

The natural frequencies for bending vibrations of Timoshenko cracked beams with simple boundary conditions have been obtained. The beam is modelled as two segments connected by two massless springs (one extensional and another one rotational). This model promotes discontinuities in both vertical displacement and rotation due to bending, which are proportional to shear force and bending moment transmitted by the cracked section, respectively. The differential equations for the free bending vibrations are established and then solved individually for each segment with the corresponding boundary conditions and the appropriated compatibility conditions at the cracked section. The problem is also solved by the perturbation method and both procedures are applied to the case of a simply supported cracked beam. The results show that the perturbation method provides simple expressions for the natural frequencies of cracked beams and it gives good results for shallow cracks.Publicad

Numerical Model to Analyze the Physicochemical Mechanisms Involved in CO₂ Absorption by an Aqueous Ammonia Droplet

This article belongs to the Special Issue Mechanical and Biomedical Engineering in Paradigm[Abstract] CO₂ is the main anthropogenic greenhouse gas and its reduction plays a decisive role in reducing global climate change. As a CO₂ elimination method, the present work is based on chemical absorption using aqueous ammonia as solvent. A CFD (computational fluid dynamics) model was developed to study CO₂ capture in a single droplet. The objective was to identify the main mechanisms responsible for CO₂ absorption, such as diffusion, solubility, convection, chemical dissociation, and evaporation. The proposed CFD model takes into consideration the fluid motion inside and outside the droplet. It was found that diffusion prevails over convection, especially for small droplets. Chemical reactions increase the absorption by up to 472.7% in comparison with physical absorption alone, and evaporation reduces the absorption up to 41.9% for the parameters studied in the present work

Improving Bi-Objective Shortest Path Search with Early Pruning.

Bi-objective search problems are a useful generalization of shortest path search. This paper reviews some recent contributions for the solution of this problem with emphasis on the efficiency of the dominance checks required for pruning, and introduces a new algorithm that improves time efficiency over previous proposals. Experimental results are presented to show the performance improvement using a set of standard problems over bi-objective road maps.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Financiado por Plan Propio de Investigación de la Universidad de Málaga (UMA), Campus de Excelencia Internacional Andalucía Tech. Work supported by the Spanish Ministry of Science and Innovation, European Regional Development Fund (FEDER), Junta de Andalucía, and Universidad de Málaga through the research projects with reference IRIS PID2021-122812OB-I00, PID2021-122381OB-I00 and UMA20-FEDERJA-065

Modelos de indexación de informes estructurados dicom-sr basados en grafos sobre infraestructuras grid avanzadas trencadis

[ES] El continuo crecimiento exponencial de la información en los entornos empresariales comienza a suponer una amenaza para los analistas de datos. Es necesario disponer de nuevas capacidades, tecnologías y modelos que nos permitan obtener ventajas sobre los actuales, basados en herramientas tradicionales de gestión de datos. Al igual que los entornos empresariales, los entes hospitalarios tienen el mismo problema, por lo que el volumen de información que generan, su velocidad de cambio y su variedad necesitan disponer de una serie de herramientas que permitan su tratamiento y visualización. Esto se enmarca en el ámbito Big Data, por lo que, es necesario solucionar la problemática expuesta siguiendo dicho término. Por ello, este proyecto desarrolla una solución a la problemática existente con la indexación de los informes estructurados asociados a las imágenes DICOM, gestionados a través de infraestructuras avanzadas basadas en TRENCADIS, dentro del contexto de Big Data. En esta tesis se ha desarrollado un modelo en el contexto Big Data basado en la teoría de grafos y se han diseñado e implementado los componentes necesarios para la integración del mismo en TRENCADIS, de forma que la indexación se realizará bajo un entorno Grid y con una base de datos noSQL basada en grafos. Se presentan una serie de pruebas para comparar los modelos propuestos con los ya existentes, y, aunque en un primer modelo el resultado no es el esperado, al refinarlo y generar un segundo modelo los resultados obtenidos mejoran la implementación actual, dando pie a futuros trabajos de tratamiento y visualización de datos.[EN] The continued exponential growth of information in enterprise environments posses many challenges to data analysis, which cannot be resolved using traditional tools. To cope with these challenges, new skills, technologies and models are needed that allow us to leverage the information. This problem is not exclusively related to business, but also public health is facing an unprecedented increase in the amount and diversity of data that needs to be stored and analysed. Big Data is providing the new generation tools for data processing and visualization. This work presents a new system to index DICOM structured reports using TRENCADIS, an advanced data infrastructure for DICOM objects. The system developed in this thesis uses graph theory to model structured reports and their interrelationships in a large noSQL database. We describe the design and the implementation of the system, as well as the integration in a Grid environment. Finally, we present a series of experiments that compare the new model to other previously published results. A second, refined model is also presented that further improves performance. The conclusions suggest the need for future lines of work in the context of data processing and visualization.Díaz De Haro, LJ. (2013). Modelos de indexación de informes estructurados dicom-sr basados en grafos sobre infraestructuras grid avanzadas trencadis. http://hdl.handle.net/10251/37561Archivo delegad

Caregiver's distress related to the patient's neuropsychiatric symptoms as a function of the care-setting

[Abstract] Prevalence of neuropsychiatric symptoms (NPS) and correlation between its intensity and caregiver distress were evaluated as a function of the care-setting in a cross-sectional study including 72 patient-caregiver dyads. The Neuropsychiatric Inventory and the Caregiver Distress Scale were administered. The most prevalent symptoms were: in the formal care-setting, agitation/aggression and depression/dysphoria (42.4%), and in the informal care-setting, aberrant motor behavior (59.0%). While changes in appetite and eating behaviors, depression/dysphoria and irritability/lability were more prevalent in the formal care-setting (p < .0001, p = .011, p = .021), aberrant motor behavior was more prevalent in the informal care-setting (p = .007). NPS were positively correlated with caregiver distress. High patients' scores in hallucinations, sleep and night-time disturbances, anxiety, and aberrant motor behavior were the best predictors of professional caregiver's distress. Agitation/aggression, delusions, disinhibition, apathy/indifference, depression/dysphoria, and elation/euphoria were the best predictors of informal caregiver's distress. Findings may have important clinical implications

Improvement of chatter stability in boring operations with passive vibration absorbers

This paper is focused on the behavior of boring bars with a passive dynamic vibration absorber (DVA) for chatter suppression. The boring bar was modeled as a cantilever Euler–Bernoulli beam and only its first mode of vibration was considered. The stability of the two-degree-of-freedom model was analyzed constructing the stability diagram, dependent on the bar characteristics and on the absorber parameters (mass, stiffness, damping, and position). Two analytical approaches for tuning the absorber parameters were compared. The selection criterion consisted on the maximization of the minimum values of the stability-lobes diagram. Subsequent analysis performed in this work, allowed formulating of new analytical expressions for the tuning frequency improving the behavior of the system against chatter.Publicad

Analysis of a thermoelastic problem with the Moore–Gibson–Thompson microtemperatures

In this paper, we study, from both an analytical and a numerical point of view, a poro-thermoelastic problem with microtemperatures. The so-called Moore–Gibson–Thompson equation is used to model the contribution for the temperature and microtemperatures. An existence and uniqueness result is proved by using the theory of linear semigroups of contractions and, for the one-dimensional case, the exponential energy decay is found under some conditions on the constitutive coefficients. Then, a fully discrete approximation is introduced by using the finite element method and the implicit Euler scheme. We show that the discrete energy decays and we obtain some a priori error estimates from which, under some adequate additional regularity conditions on the continuous solution, we derive the linear convergence of the approximations. Finally, we perform some numerical simulations to demonstrate the accuracy of the approximations and the behavior of the discrete energy and the solutionPeer ReviewedPostprint (published version