Numerical Non-Linear Modelling Algorithm Using Radial Kernels on Local Mesh Support

Estimation problems are frequent in several fields such as engineering, economics, and physics, etc. Linear and non-linear regression are powerful techniques based on optimizing an error defined over a dataset. Although they have a strong theoretical background, the need of supposing an analytical expression sometimes makes them impractical. Consequently, a group of other approaches and methodologies are available, from neural networks to random forest, etc. This work presents a new methodology to increase the number of available numerical techniques and corresponds to a natural evolution of the previous algorithms for regression based on finite elements developed by the authors improving the computational behavior and allowing the study of problems with a greater number of points. It possesses an interesting characteristic: Its direct and clear geometrical meaning. The modelling problem is presented from the point of view of the statistical analysis of the data noise considered as a random field. The goodness of fit of the generated models has been tested and compared with some other methodologies validating the results with some experimental campaigns obtained from bibliography in the engineering field, showing good approximation. In addition, a small variation on the data estimation algorithm allows studying overfitting in a model, that it is a problematic fact when numerical methods are used to model experimental values.This research has been partially funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-101148-B-I00

What Matters Most to Patients and Rheumatologists? A Discrete Choice Experiment in Rheumatoid Arthritis

Introduction: To determine patient and rheumatologist preferences for rheumatoid arthritis (RA) treatment attributes in Spain and to evaluate their attitude towards shared decision-making (SDM). Methods: Observational, descriptive, exploratory and cross-sectional study based on a discrete choice experiment (DCE). To identify the attributes and their levels, a literature review and two focus groups (patients [P] = 5; rheumatologists [R] = 4) were undertaken. Seven attributes with 2–4 levels were presented in eight scenarios. Attribute utility and relative importance (RI) were assessed using a conditional logit model. Patient preferences for SDM were assessed using an ad hoc questionnaire. Results: Ninety rheumatologists [52.2% women; mean years of experience 18.1 (SD: 9.0); seeing an average of 24.4 RA patients/week (SD: 15.3)] and 137 RA patients [mean age: 47.5 years (SD: 10.7); 84.0% women; mean time since diagnosis of RA: 14.2 years (SD: 11.8) and time in treatment: 13.2 years (SD: 11.2), mean HAQ score 1.2 (SD: 0.7)] participated in the study. In terms of RI, rheumatologists and RA patients viewed: time with optimal QoL: R: 23.41%/P: 35.05%; substantial symptom improvement: R: 13.15%/P: 3.62%; time to onset of treatment action: R: 16.24%/P: 13.56%; severe adverse events: R: 10.89%/P: 11.20%; mild adverse events: R: 4.16%/P: 0.91%; mode of administration: R: 25.23%/P: 25.00%; and added cost: R: 6.93%/P: 10.66%. Nearly 73% of RA patients were involved in treatment decision-making to a greater or lesser extent; however, 27.4% did not participate at all. Conclusion: Both for rheumatologists and patients, the top three decision-making drivers are time with optimal quality, treatment mode of administration and time to onset of action, although in different ranking order. Patients were willing to be more involved in the treatment decision-making process

Predicting the spread of epidemiological diseases by using a multi-objective algorithm

The epidemiological models are able to predict the spread of diseases, but a previous work on calibrating some involved parameters must be done. In this work, we propose a methodology to adjust those parameters based on solving a multi-objective optimization problem whose objective functions measure the accuracy of the model. More precisely, we have considered the Between-Countries Disease Spread model because it involves a set of countries taking into account the migratory movements among them. As a result, using some real data about the number of detected cases and the number of deaths for the Ebola virus disease, we have shown that the methodology is able to find a set of values for the parameters so that the model fits the outbreak spread for a set of countries

Assessment of the mechanical and thermal properties of injection-molded poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)/hydroxyapatite nanoparticles parts for use in bone tissue engineering

In the present study, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] was reinforced with hydroxyapatite nanoparticles (nHA) to produce novel nanocomposites for potential uses in bone reconstruction. Contents of nHA in the 2.5–20 wt % range were incorporated into P(3HB-co-3HHx) by melt compounding and the resulting pellets were shaped into parts by injection molding. The addition of nHA improved the mechanical strength and the thermomechanical resistance of the microbial copolyester parts. In particular, the addition of 20 wt % of nHA increased the tensile (Et) and flexural (Ef) moduli by approximately 64% and 61%, respectively. At the highest contents, however, the nanoparticles tended to agglomerate, and the ductility, toughness, and thermal stability of the parts also declined. The P(3HB-co-3HHx) parts filled with nHA contents of up to 10 wt % matched more closely the mechanical properties of the native bone in terms of strength and ductility when compared with metal alloys and other biopolymers used in bone tissue engineering. This fact, in combination with their biocompatibility, enables the development of nanocomposite parts to be applied as low-stress implantable devices that can promote bone reconstruction and be reabsorbed into the human body.L.Q.-C. wants to thank GVA for his FPI grant (ACIF/2016/182) and the Spanish Ministry of Education, Culture, and Sports (MECD) for his FPU grant (FPU15/03812). S.T.-G. acknowledges MICI for his Juan de la Cierva–Incorporación contract (IJCI-2016-29675). J.I.-M. wants to thank Universitat Politècnica de València for his FPI grant (PAID-2019- SP20190011). Microscopy services of the Universitat Politècnica de València (UPV) are acknowledged for their help in collecting and analyzing the FESEM images. Authors also thank Ercros S.A. for kindly supplying ErcrosBio® PH110.This research work was funded by the Spanish Ministry of Science and Innovation (MICI) project numbers RTI2018-097249-B-C21 and MAT2017-84909-C2-2-R and the POLISABIO program with grant number 2019-A02

The domestication syndrome in Phoenix dactylifera seeds : toward the identification of wild date palm populations

Investigating crop origins is a priority to understand the evolution of plants under domestication, develop strategies for conservation and valorization of agrobiodiversity and acquire fundamental knowledge for cultivar improvement. The date palm(Phoenix dactylifera L.) belongs to the genus Phoenix, which comprises 14 species morphologically very close, sometimes hardly distinguishable. It has been cultivated for millennia in the Middle East and in North Africa and constitutes the keystone of oasis agriculture. Yet, its origins remain poorly understood as no wild populations are identified. Uncultivated populations have been described but they might represent feral, i.e. formerly cultivated, abandoned forms rather than truly wild populations. In this context, this study based on morphometrics applied to 1625 Phoenix seeds aims to (1) differentiate Phoenix species and (2) depict the domestication syndrome observed in cultivated date palm seeds using other Phoenix species as a "wild" reference. This will help discriminate truly wild from feral forms, thus providing new insights into the evolutionary history of this species. Seed size was evaluated using four parameters: length, width, thickness and dorsal view surface. Seed shape was quantified using outline analyses based on the Elliptic Fourier Transform method. The size and shape of seeds allowed an accurate differentiation of Phoenix species. The cultivated date palm shows distinctive size and shape features, compared to other Phoenix species: seeds are longer and elongated. This morphological shift may be interpreted as a domestication syndrome, resulting from the long-term history of cultivation, selection and human-mediated dispersion. Based on seed attributes, some uncultivated date palms from Oman may be identified as wild. This opens new prospects regarding the possible existence and characterization of relict wild populations and consequently for the understanding of the date palm origins. Finally, we here describe a pipeline for the identification of the domestication syndrome in seeds that could be used in other crops

Construcción de esculturas de hormigón con elementos procedentes del reciclado

This paper shows the conceptual development, project, constructive and execution processes of a group of seven sculptures designed to act as containers of other art works carried out by the Spanish artist Jesús Soler. This sculptural group bases its message on the sustainability and the recycling of materials. Its fundamental boundary conditions are the capacity to be mounted and dismounted without any anchorage to the soil, durability and protection of the art work in front of meteorological agents. The sculptural group transmits by itself an environmental message. This paper describes the geometry and proportions, based on the “Le Corbusier Modulor” and the golden section, as well as all the constructive techniques applied for the correct design of each sculpture: formwork systems, concrete with recycled arid, corten steel frames, anchorages, etc. Finally the first assembly process of this itinerant sculptural work is described; it is mounted in the Parque del Retiro in the city of Madrid (Spain).Este trabajo recoge el desarrollo conceptual, de proyecto, construcción y de ejecución de un conjunto de siete esculturas disenadas para actuar como contenedores de otras obras de arte (17 cuadros) realizadas por el artista Jesús Soler. Este conjunto escultórico basa su mensaje en la sostenibidad y el reciclaje. Presenta, como condiciones de contorno fundamentales, la capacidad de ser montado y desmontado sin necesidad de anclar al terreno, durabilidad y protección de las obras frente a agentes meteorológicos y todo ello transmitiendo por sí mismas un mensaje medioambiental. Se describe en el documento la geometría y proporciones basadas en el “Modulor” de Le Corbusier y, por consiguiente, en la sección áurea, así como todas las técnicas constructivas aplicadas para el correcto diseno de cada obra: sistemas de encofrado, hormigones con áridos reciclados, marcos de acero corten, anclajes, etc. Finalmente se describe el primer proceso de montaje de esta obra itinerante, en el Parque del Retiro de Madrid

Estudio de la fluencia de una calcarenita: la Piedra de San Julián (Alicante)

Rocks creep has a great importance in the evaluation of the long-term behaviour of elements built with or within these materials. In this work, a porous well-known limestone locally named as San Julián stone has been physically and mechanically characterized. Uniaxial compressive tests for 96 h. at constant stress are carried out. Long-term behaviour has been modelled by means of a well-known creep model, the CEB-FIP Model code 2010, used for modelling other stony-material (i.e. concrete). Furthermore, a rheological model has been proposed. The main aim of this work is to investigate the possibility of exploiting the vast experience accumulated in the study of concrete deformational long-term behaviour in order to obtaining a reasonable approach to the behaviour of the rock, for too long testing times difficult to implement in laboratory. A creep function adapted to the studied rock only dependent on its elastic and mechanical characteristics is also proposed in this work.La fluencia de las rocas tiene gran importancia en la evaluación del comportamiento a largo plazo de elementos construidos con estos materiales. En este trabajo, se ha caracterizado física y mecánicamente una calcarenita porosa bien conocida localmente como Piedra de San Julián. Se han realizado ensayos de compresión uniaxial de 96 h. a carga constante. Se ha utilizado un modelo de fluencia bien conocido, el Código-modelo CEB-FIP 2010, usado para modelizar otro material pétreo (hormigón). Además, se ha propuesto un modelo reológico. El objetivo principal de este trabajo es investigar la posibilidad de aprovechar la gran experiencia acumulada en el estudio del hormigón, con el fin de obtener un enfoque para el comportamiento de la roca, para tiempos de prueba muy largos difíciles de implementar en laboratorio. Se propone una función de fluencia adaptada a la roca estudiada dependiente sólo de sus características elásticas y mecánicas

Diseño y análisis de productos y espacios con técnicas de prototipado virtual interactivo

[ES] El trabajo muestra cómo el empleo de técnicas de visualización inmersiva influyen en el proceso creativo, mejorando las ideas proyectadas y facilitando un análisis de los productos y espacios ideados. Se plasma el proceso innovador de la asignatura “Visualizaciones avanzadas. Realidad virtual aplicada al diseño de productos” impartida en el Máster Universitario de Ingeniería del Diseño, de la ETSID-UPV, en donde el alumnado idea, diseña y experimenta con modelos tridimensionales, visualizados en soportes bidimensionales y maquetas y prototipos virtuales inmersivos. Se muestra el trabajo desde la motivación, la sorpresa, la aproximación a la realidad más tangible y un conjunto de acciones derivadas de esa aproximación que posibilita al estudiante ver su proyecto hecho realidad. La evolución de la tecnología y su implementación en la universidad permite, a su vez, implementar la docencia con herramientas que ya están al alcance del alumnado, convirtiendo la experiencia docente en la máxima aproximación a la realidad laboral que en breve les espera.[EN] This work shows how the use of immersive visualization techniques can influence the creative process, improving the projected ideas and making the analysis of the products and spaces designed easier. The innovative process of the course "Advanced Visualizations. Virtual reality applied to the design of products" taught in the Master's Degree in Design Engineering, ETSID-UPV, where the students think, design and experiment with three-dimensional models visualized on two-dimensional media, models and immersive virtual prototypes. The work is shown from the motivation, the surprise and the approach to the most tangible reality and a set of actions derived from that approach that allows the student to see his project come real. The evolution of technology and its implementation at the university allows, to improve teaching with tools that are already available to students, making the teaching experience the maximum approach to the career that will soon come to them.Saiz Mauleón, B.; Ivorra Martínez, E.; Verdejo Gimeno, P.; Cisneros Vivó, JJ. (2021). Diseño y análisis de productos y espacios con técnicas de prototipado virtual interactivo. En IN-RED 2020: VI Congreso de Innovación Educativa y Docencia en Red. Editorial Universitat Politècnica de València. 388-401. https://doi.org/10.4995/INRED2020.2020.11953OCS38840

Dynamic behaviour of a novel transition wedge composed by prefabricated reinforced concrete slabs

Abrupt variations of track stiffness in transitions from conventional to slab track, e.g., over bridges and tunnels, usually lead to passenger discomfort, vehicle and track damage and even safety issues. Therefore, to minimize this negative effect, it is very convenient to smooth the stiffness changes in such transitions; and wedges arise as a very effective technique. Although granular wedges are commonly suggested by railroad managers as a solution, this typology presents some disadvantages, e.g., high construction time and costs, that should be addressed. In this paper, a new solution based on prefabricated, reinforced concrete slabs is presented and its dynamical performance is assessed by means of a 3D FEM model. Results indicate that track vibrations both on the rail and over a sleeper are considerably reduced when the new slab-based wedge is considered instead of a traditional granular wedge