A DECOMPOSITION PROCEDURE BASED ON APPROXIMATE NEWTON DIRECTIONS

The efficient solution of large-scale linear and nonlinear optimization problems may require exploiting any special structure in them in an efficient manner. We describe and analyze some cases in which this special structure can be used with very little cost to obtain search directions from decomposed subproblems. We also study how to correct these directions using (decomposable) preconditioned conjugate gradient methods to ensure local convergence in all cases. The choice of appropriate preconditioners results in a natural manner from the structure in the problem. Finally, we conduct computational experiments to compare the resulting procedures with direct methods, as well as to study the impact of different preconditioner choices.

Stochastic Optimal Power Flow Based on Data-Driven Distributionally Robust Optimization

We propose a data-driven method to solve a stochastic optimal power flow (OPF) problem based on limited information about forecast error distributions. The objective is to determine power schedules for controllable devices in a power network to balance operation cost and conditional value-at-risk (CVaR) of device and network constraint violations. These decisions include scheduled power output adjustments and reserve policies, which specify planned reactions to forecast errors in order to accommodate fluctuating renewable energy sources. Instead of assuming the uncertainties across the networks follow prescribed probability distributions, we assume the distributions are only observable through a finite training dataset. By utilizing the Wasserstein metric to quantify differences between the empirical data-based distribution and the real data-generating distribution, we formulate a distributionally robust optimization OPF problem to search for power schedules and reserve policies that are robust to sampling errors inherent in the dataset. A simple numerical example illustrates inherent tradeoffs between operation cost and risk of constraint violation, and we show how our proposed method offers a data-driven framework to balance these objectives

Empleo y comunidad gitana: claves de actuación

.Gypsies are the community at greatest risk of exclusion from the job market, and facing the most difficulties f or access to proper work. Construction of a modern , united and socially integrated Europe depends on overcoming inequalities of not only a territorial but also a social nature. That is why the identification of the factors that act as barriers to equality, as well as the implementation ofrealistic, relevant and innovative insertion steps oriented loward excluded groups are essential processes to promote ajob marketthat is opento all citizens.La población gitana es la comunidad que sufre un mayor riego de exclusión del mercado laboral y mayores dificultades de acceso al trabajo normalizado. La construcción de una Europa moderna , cohesionada y socialmente integrada pasa por la supera ción de los desequilibrios, no solo territoriales, sino también sociales. Es por ello, que la identificación de los factores que actúan como barreras para la igualdad, así como la adopción de medidas de inserción realistas, pertin entes e innovadoras dirigidas a los colectivos excluidos son procesos básicos para promover un mercado de trabajo abierto a todos

A ferrofluid-based sensor to measure bottom shear stresses under currents and waves

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Journal of Hydraulic Research on 2018, available online at: http://www.tandfonline.com/10.1080/00221686.2017.1397779The measurement of the near-bottom flow characteristics is crucial to correctly understand coastal processes. To overcome some of the limits of present state-of-the-art measuring instruments, we propose a novel approach to measure bottom shear stress under currents and waves based on the exploitation of magneto-rheological fluids, named ferrofluids. In particular, the deformation of a magnetically controlled ferrofluid drop O(0.01 ml) is transformed by a conditioning circuit into an output voltage which is proportional to the bottom shear stress. Calibration curves are presented for both steady-current and regular wave conditions, over fixed and weakly mobile beds, showing that the behaviour of the proposed measuring system can be assumed linear. In the range of the investigated parameters, it is shown that the working range is comprised between 0.08 N m-2 and an upper limit which is a function of the controlling magnetic field and the flow type.Peer ReviewedPostprint (author's final draft

The Gothic element in Victorian Female Narrative

El propósito de este trabajo es explicar los elementos del género gótico que aparecen en la narrativa escrita por las hermanas Brontë y Elizabeth Gaskell. La primera sección se centra en las características de la narrativa gótica y en su influencia en autores posteriores. Esta parte está dividida en dos subapartados. El primer subapartado ofrece una explicación sobre la invención de los primeros elementos góticos creados por el escritor Horace Walpole mientras que el segundo subapartado trata sobre el nacimiento del Gótico Femenino gracias a los trabajos de Ann Radcliffe y las diferencias de éste con el gótico escrito por hombres. La segunda sección está centrada en el análisis de obras escritas por mujeres durante el período Victoriano: dos novelas escritas por Charlotte y Anne Brontë respectivamente y dos historias cortas de Elizabeth Gaskell. La última sección ofrece un análisis más detallado de la novela Cumbres Borrascosas de Emily Brontë.The purpose of this study is to explain the elements from the gothic genre which appear in the narrative written by the Brontë sisters and Elizabeth Gaskell. The first section focuses on the characteristics of Gothic fiction and how it influences in subsequent authors. This part will be divided in two subsections. The first subsection offers an explanation about the introduction of the first gothic elements by Horace Walpole whereas the second subsection deals with the rise of Female gothic through the works of Ann Radcliffe and its differences with traditional male Gothic fiction. The second section focuses on the analysis of works written by female authors in the Victorian period: two novels written by Charlotte and Anne Brontë respectively, and two short stories written by Elizabeth Gaskell. The final section offers a more detailed analysis of the novel Wuthering Heights written by the novelist Emily Brontë.Departamento de Filología InglesaGrado en Estudios Inglese

d8···d10 RhI···AuI Interactions in Rh 2,6-Xylylisocyanide Complexes with [Au(CN)2]: Bond Analysis and Crystal Effects

Producción CientíficaThe well known [RhL4]n(anion)n structures, with RhI···RhI d8···d8 interactions, are replaced by others with RhI···AuI d8···d10 interactions such as [{RhL4}{Au(CN)2}] (L = 2,6-Xylylisocyanide) or [{RhL4}{Au(CN)2} {RhL4}{Au2(CN)3}·4(CHCl3)]∞ when the anion is [Au(CN)2]–. Orbital (Rh···Au), coulombic, and inter-unit π-π aryl stacking interactions stabilize these crystal structures.Ministerio de Economía, Industria y Competitividad (grant CTQ2017-89217-P)Junta de Castilla y León (project VA038G18

El discurso de género más allá de los términos de los diccionarios

Los diccionarios son herramientas de consulta que se toman como referentes del eje de comprensión y expresión común. Como intermediarios en el hecho comunicativo, pueden interceder en el diálogo entre la individualidad y el paradigma social de una lengua dada. Al intervenir de forma puntual, se puede obviar que hilando la interpretación de los lemas, un diccionario conlleva una o varias políticas-lingüísticas, ideologías, o corrientes de pensamiento no exentas de una interpretación de género que, en su conjunto, ejemplifican el ámbito simbólico de un idioma, tampoco ajeno a interpretaciones sesgadas. Como auctoritas, se hace necesario analizar la perspectiva de género de estas herramientas proponiendo tres niveles de análisis del discurso más allá del simple análisis de sus términos

A decomposition procedure based on approximate newton directions

The efficient solution of large-scale linear and nonlinear optimization problems may require exploiting any special structure in them in an efficient manner. We describe and analyze some cases in which this special structure can be used with very little cost to obtain search directions from decomposed subproblems. We also study how to correct these directions using (decomposable) preconditioned conjugate gradient methods to ensure local convergence in all cases. The choice of appropriate preconditioners results in a natural manner from the structure in the problem. Finally, we conduct computational experiments to compare the resulting procedures with direct methods, as well as to study the impact of different preconditioner choices