Optimization models in solar power tower plant design. Design of the heliostat field and the tower receivers

Falta palabras clavesEl diseño de plantas solares con tecnología de torre (utilizaremos las siglas en inglés SPT) comenzó a ser estudiado en los años 70 y sigue siendo hoy en día un área de investigación muy activa. En esta tesis doctoral se estudia el diseño óptimo de la planta solar bajo distintos aspectos, enfocándose en el diseño del sistema torre-receptor y del campo de heliostatos. El primer capítulo presenta una idea general sobre SPT, describiendo los componentes que intervienen en el problema y detallando el modelado matemático utilizado a lo largo de este documento. Un algoritmo para resolver el problema de base se propone en el Capítulo 2. Se trata de un algoritmo, basado en la heurística voraz, que introduce un enfoque innovador al resolver el problema de la localización de heliostatos sin pre-establecer ningún patrón geométrico. Este algoritmo se extiende en el Capítulo 3 para resolver el diseño del campo solar con heliostatos en bloques llamados “pod” (estructuras triangulares que albergan varios heliostatos). Los capítulos 4 y 5 versan sobre los procedimientos heurísticos adaptados para dar solución a nuevos problemas que surgen en este tipo de tecnologías: diseño de sistemas con receptores múltiples y diseño de campos multi-talla. Ambos son problemas desafiantes debido a su alto grado de complejidad. El algoritmo heurístico presentado en el Capítulo 2 ha sido modificado y combinado con distintos procedimientos de optimización para facilitar una solución, que aunque no óptima, sea competitiva y pueda ser considerada como una buena solución. A lo largo de todos los capítulos, los resultados han sido comparados con los resultados disponibles en la literatura. Esto ha permitido validar los algoritmos propuestos. Las conclusiones generales y algunos comentarios sobre trabajos futuros se comentan en el último capítulo.The design of solar power tower (SPT) plants started to be studied in 1970s and is still being an active field of research nowadays. In this dissertation, the optimal design of an SPT plant under different considerations is addressed, focusing on the tower-receiver and heliostat field design. The first chapter provides the general ideas on SPT plants, with a description of the components involved in the problem and a presentation of the mathematical modelling used in this document. An algorithm to solve the basic problem is proposed in Chapter 2. It is a greedy-based heuristic algorithm, which introduces an innovative approach solving the heliostat location problem without fixing geometrical patterns. This algorithm is extended in Chapter 3 to address the solar field design with heliostat pod systems (triangular structures having several heliostats on it). Chapters 4 and 5 concern heuristic procedures adapted to the solution of innovative problems arising in this technology: multiple receivers system design and multi-size-heliostat field design. Both are challenging problems due to their high complexity. The heuristic algorithm in Chapter 2 has been modified and combined with different optimization procedures in order to furnish a solution which, although not optimal, is competitive and can be considered as a good solution. Along all the chapters, the results have been compared to the state-ofthe- art results, when available. This has allowed to validate the proposed algorithms. The general conclusions and some comments on further work are commented in the last chapter

An optimization tool to design the field of a solar power tower plant allowing heliostats of different sizes

The design of a Solar Power Tower plant involves the optimization of the heliostat field layout. Fields are usually designed to have all heliostats of identical size. Although the use of a single heliostat size has been questioned in the literature, there are no tools to design fields with heliostats of several sizes at the same time. In this paper, the problem of optimizing the heliostat field layout of a system with heliostats of different sizes is addressed. We present an optimization tool to design solar plants allowing two heliostat sizes. The methodology is illustrated with a particular example considering different heliostat costs.Ministerio de Economía y CompetitividadJunta de AndalucíaGobierno VascoUnión Europe

Optimization of multiple receivers solar power tower systems

In this article a new procedure to optimize the design of a Multiple Receivers Solar Power Tower system is presented. The proposed procedure allows to optimize the different receivers (height, aperture tilt angle, azimuth angle and aperture size) as well as the heliostat field layout, seeking to minimize the levelized cost of thermal energy. The optimization problem is high dimensional, with a black-box nonconvex objective function that is hard to compute. Our method is based on an alternating greedy-based heuristic method, already used by the authors to design a system with a single receiver, which simultaneously optimizes the receivers and the heliostat field. The proposed procedure allows one to determine the overall number of heliostats, their locations and the aiming region of each field.Abengoa Solar New TechnologiesInstituto de Matemáticas de la Universidad de SevillaMinisterio de Ciencia e InnovaciónMinisterio de Economía y CompetitividadJunta de AndalucíaEuropean Unio

A heuristic method for simultaneous tower and pattern-free field optimization on solar power systems

A heuristic method for optimizing a solar power tower system is proposed, in which both heliostat field (heliostat locations and number) and the tower (tower height and receiver size) are simultaneously considered. Maximizing the thermal energy collected per unit cost leads to a difficult optimization problem due to its characteristics: it has a nonconvex black-box objective function with computationally expensive evaluation and nonconvex constraints. The proposed method sequentially optimizes the field layout for a given tower configuration and then, the tower design is optimized for the previously obtained field layout. A greedy-based heuristic algorithm is presented to address the heliostat location problem. This algorithm follows a pattern-free method. The only constraints to be considered are: the field region and the nonconvex constraints (which allow heliostats to not collide). The absence of a geometrical pattern to design the field and the simultaneous optimization of the field and the tower designs make this approach different from the existing ones. Our method is compared against other proposals in the literature of heliostat field optimization.Abengoa Solar New TechnologiesInstituto de Matemáticas (Universidad de Sevilla)Ministerio de Economía y CompetitividadJunta de AndalucíaEuropean Cooperation in Science and Technolog

Protagonismo del mentor en una actividad tutorial de carácter multidisciplinar en Ingeniería

XIX Congreso Universitario de Innovación Educativa en las Enseñanzas Técnicas : Barcelona, 6 a 8 de julio de 2011En la Escuela Politécnica Superior (EPS) de la Universidad de Sevilla se ha trabajado, por tercer curso consecutivo, en un Plan de Acción Tutorial desarrollado por 16 profesores tutores y 20 alumnos mentores de 5 titulaciones de Ingeniería Técnica. El objetivo perseguido en este curso ha sido potenciar actividades que han surgido del propio albedrío de los alumnos mentores, lo que ha dado como resultado la realización de una serie de actividades de mentoría motivadas y dirigidas desde el principio por los alumnos mentores. La actividad conjunta de todos ellos ha llevado a organizar unos subgrupos de mentorías en función de determinadas características del alumnado de primer curso (deportistas, trabajadores, becarios de otras universidades…), a realizar reuniones presenciales de mentores para puesta a punto de estas actividades así como de puesta al día de los resultados que se iban consiguiendo, además de organizar una segunda captación de mentorizados tras las notas del primer cuatrimestre, y la protagonización de una Jornada de Mentoría al final del curso.A third edition with 16 tutorial lecturers and 20 tutorial students from five different degrees (Technical Engineering of the Polytechnical School, EPS, at University of Seville) in a Tutorial Plan development, has been prepared. During the present year, the main characteristic has been a serial of mentoring actions motivated and directed by these mentors. This activity has been organized considering several subgroups of mentoring depending on special characteristics in first year students (sportsplayers, workers, grant holders from other universities…), moreover the organization of a second recruiting of new students after the first term marks, updating meetings for mentors only, and to be main figures in a Congress on Mentoring at the end of the academic year

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

COVID-19 vaccine failure

COVID-19 affects the population unequally with a higher impact on aged and immunosuppressed people. Hence, we assessed the effect of SARS-CoV-2 vaccination in immune compromised patients (older adults and oncohematologic patients), compared with healthy counterparts. While the acquired humoral and cellular memory did not predict subsequent infection 18 months after full immunization, spectral and computational cytometry revealed several subsets within the CD8+ T-cells, B-cells, NK cells, monocytes and CD45RA+ CCR7- Tγδ cells differentially expressed in further infected and non-infected individuals not just following immunization, but also prior to that. Of note, up to 7 subsets were found within the CD45RA+ CCR7- Tγδ population with some of them being expanded and other decreased in subsequently infected individuals. Moreover, some of these subsets also predicted COVID-induced hospitalization in oncohematologic patients. Therefore, we hereby have identified several cellular subsets that, even before vaccination, strongly related to COVID-19 vulnerability as opposed to the acquisition of cellular and/or humoral memory following vaccination with SARS-CoV2 mRNA vaccines.This study has been funded through Programa Estratégico Instituto de Biología y Genética Molecular (IBGM Junta de Castilla y León. Ref. CCVC8485), Junta de Castilla y León (Proyectos COVID 07.04.467B04.74011.0) and the European Commission – NextGenerationEU (Regulation EU 2020/2094), through CSIC's Global Health Platform (PTI Salud Global; SGL21-03-026 and SGL2021-03-038)N

Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| &lt; 0.03 at 95% confidence level. [Figure not available: see fulltext.

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

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