Loss Allocation in Distribution Networks Based on Aumann-Shapley

This paper outlines a procedure for loss allocation in both radial and meshed distribution networks with distributed generation that could be regulated in various ways. The method is analytically developed based on the theory of electrical circuits combined with game theory based on Aumann&-Shapley, which guarantees both the electrical principles and the fair axioms of game theory. The proposed method obtains unitary participation coefficients for each network user based on the currents demanded/injected by each user and the network topology. The proposed allocation method based on Aumann&-Shapley has been compared with other traditional allocation methods, is adaptable to distribution networks, and shows great potential and ease of implementation. Moreover, it can be applied to any kind of distribution network (radial or meshed) with distributed energy resources

Photovoltaic reactive power limits

Today, Photovoltaic (PV) inverters are working with very small values of reactive power. Then, the Power Factor (PF) is very close to the unit. So, the PV installations only inject active power into the grid. This paper aims to investigate the limits of reactive power capacity in PV generators. In this way, PV generators could be used as a controlled reactive power sources. In this paper, an introduction to the voltage control in photovoltaic generators is described and implemented in Simulink/Matlab and PSS/E.The Spanish Ministry of Education and Science has supported this research under contract ENE2009-13883-C02-C1.Publicad

Inequality and psychological well-being in times of COVID-19: evidence from Spain

Mediante dos nuevas encuestas online llevadas a cabo en mayo y noviembre de 2020, en este documento estudiamos las consecuencias de las primeras etapas de la pandemia de COVID-19 para los hogares españoles. Documentamos un efecto importante y negativo sobre los ingresos de los hogares. En mayo de 2020, el hogar promedio había perdido el 16 % de sus ingresos prepandemia. Además, esta caída fue muy desigual: mientras que los hogares del quintil más rico perdieron el 6,8 % de sus ingresos, los del quintil más pobre perdieron el 27 %. También mostramos que la pandemia hizo más profunda la brecha de género en ingresos: en promedio, las mujeres experimentaron una pérdida de ingresos tres puntos porcentuales mayor que la de los hombres. Si bien esto es coherente con hallazgos anteriores de la literatura, en este trabajo documentamos que este efecto se debe a la evolución de los ingresos de las mujeres en hogares de ingresos medios. Finalmente, proporcionamos evidencia de que los españoles experimentaron descensos moderados en sus niveles de bienestar psicológico. Este efecto es similar para las personas de diferentes niveles de ingresos. Sin embargo, las razones que hay detrás de las pérdidas de bienestar difieren: las personas más ricas están más preocupadas por la pérdida de contacto con sus seres queridos, mientras que las personas de bajos ingresos es más probable que mencionen la pérdida de ingresos y del empleo como un motivo clave de deterioro emocional.Using two novel online surveys collected in May and November 2020, we study the consequences of the first stages of the COVID-19 pandemic on Spanish households. We document a large and negative effect on household income. By May 2020 the average individual lived in a household that had lost 16% of their pre-pandemic monthly income. Furthermore, this drop was highly unequal: while households in the richest quintile lost 6.8% of their income, those in the poorest quintile lost 27%. We also document that the pandemic deepened the gender-income gap: on average, women experienced a three-percentage-point larger income loss than men. While this is consistent with previous findings in the literature, in this paper we document that this effect is driven by women from middle-income households with kids. Finally, we provide evidence that Spanish individuals experienced moderate declines in their levels of psychological well-being. This effect is not different for individuals living in rich or poor households, but the reasons behind well-being losses do differ: richer individuals are more concerned about loss of contact with dear ones, while low-income individuals are more likely to mention loss of income and employment as a key source of emotional distress

Morpho-Functional Architecture of the Golgi Complex of Neuroendocrine Cells

In neuroendocrine cells, prohormones move from the endoplasmic reticulum to the Golgi complex (GC), where they are sorted and packed into secretory granules. The GC is considered the central station of the secretory pathway of proteins and lipids en route to their final destination. In most mammalian cells, it is formed by several stacks of cisternae connected by tubules, forming a continuous ribbon. This organelle shows an extraordinary structural and functional complexity, which is exacerbated by the fact that its architecture is cell type specific and also tuned by the functional status of the cell. It is, indeed, one the most beautiful cellular organelles and, for that reason, perhaps the most extensively photographed by electron microscopists. In recent decades, an exhaustive dissection of the molecular machinery involved in membrane traffic and other Golgi functions has been carried out. Concomitantly, detailed morphological studies have been performed, including 3D analysis by electron tomography, and the precise location of key proteins has been identified by immunoelectron microscopy. Despite all this effort, some basic aspects of Golgi functioning remain unsolved. For instance, the mode of intra-Golgi transport is not known, and two opposing theories (vesicular transport and cisternal maturation models) have polarized the field for many years. Neither of these theories explains all the experimental data so that new theories and combinations thereof have recently been proposed. Moreover, the specific role of the small vesicles and tubules which surround the stacks needs to be clarified. In this review, we summarize our current knowledge of the Golgi architecture in relation with its function and the mechanisms of intra-Golgi transport. Within the same framework, the characteristics of the GC of neuroendocrine cells are analyzed

Memoria de las prácticas profesionales

Treball Final de Màster Universitari en Traducció Medicosanitària. Codi: SBA031. Curs: 2021/2022Este trabajo de fin de máster (TFM) representa la culminación del Máster Universitario en Traducción Médico-Sanitaria realizado en la Universitat Jaume I (UJI) durante el curso académico 2021-22. El TFM se realiza en el contexto de la asignatura SBA033 - Prácticas Profesionales, que permite a los estudiantes llevar a cabo un encargo de traducción para un cliente real. Así, el TFM constituye el trabajo académico que plasma la reflexión sobre esta experiencia profesional, tanto sobre el proceso como sobre el resultado de la traducción realizada. Aunque se permite a los estudiantes realizar las prácticas en empresas de su elección, la UJI ya dispone de un convenio con la Editorial Médica Panamericana, editorial de larga trayectoria y gran renombre en el ámbito biomédico hispanohablante. Además, desde un punto de vista personal, la traducción en el sector editorial me resulta de gran interés porque me permite explotar al máximo mi bagaje científico y ponerlo al servicio de la traducción de textos especializados. Por este motivo, realizar las prácticas profesionales en la Editorial Médica Panamericana no solo representaba una gran oportunidad, sino que también era la opción más adecuada a mi perfil y mis futuros intereses profesionales. Con el espíritu de ofrecer al estudiante una experiencia profesional lo más real posible, las prácticas simularon el proceso al que un traductor profesional se enfrenta en su día a día. A tal efecto, unos días antes de iniciar las prácticas se nos pidió redactar una carta de presentación para la editorial y realizamos una prueba de traducción. Finalmente, firmamos también un contrato de prácticas. En cuanto a la organización de las prácticas, se nos ofrecieron dos itinerarios posibles para realizarlas. A grandes rasgos, el itinerario intensivo consistía en realizar las prácticas en grupo, con un volumen de traducción de unas 1.500 palabras, mientras que en el itinerario estándar las prácticas se realizaban de manera individual y con un volumen de traducción mayor, de unas 3.000 palabras aproximadamente. Opté por este último itinerario ya que consideré que ofrecía una experiencia más real y que me permitiría poner a prueba en mayor grado las competencias adquiridas a lo largo del máster, además de facilitar el desarrollo de un método de trabajo propio, con total autonomía para organizar y realizar el trabajo. A continuación se describen las características del encargo de traducción, se ofrece una síntesis de los principales contenidos del fragmento traducido y se lleva a cabo un análisis textual de la obra traducida

Gestión óptima de potencia reactiva en sistemas eléctricos con generación eólica

En las últimas décadas se está produciendo una evolución creciente de la demanda que sitúa el punto de trabajo de los sistemas de potencia próximos a sus límites físicos de funcionamiento. Muchos son los ejemplos de problemas de estabilidad de tensión relacionados con este aumento de carga a lo largo de todo el mundo. Los sistemas de compensación de reactiva se presentan como una buena alternativa para aliviar los problemas relacionados con la estabilidad de tensión; por lo que, la planificación de potencia reactiva en grandes sistemas eléctricos cobra especial importancia, desarrollándose nuevas técnicas para su resolución. Las técnicas metaheurísticas se perfilan como una buena alternativa para resolver el problema de gestión óptima de la potencia reactiva, entendido como operación, localización y dimensionado óptimo de estas unidades. Entre ellas, los algoritmos genéticos destacan por su rapidez de cálculo y su sencillez. El incremento de la penetración de la energía eólica en los sistemas de potencia, motivado por los incentivos del uso de las fuentes de energía renovables, ha supuesto la creación en diferentes países de códigos de conexión a red. Estos códigos establecen requisitos de operación para los parques eólicos encaminados a favorecer la máxima incorporación de energía eólica en los sistemas eléctricos a la vez que se exige a esta generación un comportamiento similar al de las centrales convencionales. Entre todas las tecnologías empleadas para la generación de electricidad a partir del recurso eólico, el generador asíncrono doblemente alimentado ha experimentado un gran auge gracias a la capacidad de controlar la potencia activa y reactiva entregada a la red. En esta tesis se ha desarrollado un algoritmo genético para la gestión óptima de la potencia reactiva en sistemas eléctricos con generación eólica. Las unidades generadoras de potencia reactiva consideradas son los dispositivos estáticos de compensación de potencia reactiva y los aerogeneradores asíncronos doblemente alimentados, empleados para controlar la tensión en toda la red. Las estrategias de optimización propuestas permiten localizar de forma óptima las unidades de compensación de reactiva y gestionar la inyección de potencia reactiva para satisfacer diferentes escenarios de carga y generación de los sistemas de eléctricos. Finalmente, se comprueban los beneficios asociados a la incorporación óptima de unidades de generación de potencia reactiva en el sistema en cuanto a criterios de seguridad de red se refiere.---------------------------------------------------------------------------------------------------------During the last decades there has been an upward trend in demand, which places the operating point of power systems closer to their physical limits of operation. There are many examples of voltage stability problems caused due to the demand increase throughout the world. Reactive power compensation systems are presented as a good alternative that aims to alleviate problems related to voltage stability. Therefore reactive power planning in large power systems has become a particularly important point in recent years since it is necessary to develop new techniques to solve any problem that may arise. Moreover, Metaheuristic techniques has come up to be a good alternative to resolve the problem of optimal management of reactive power, which involves operation, location and optimal size of these units. Among these techniques genetic algorithms stand out because of their speed of calculation and simplicity. The increased penetration trend of wind energy in power systems, caused mostly by the incentives to use renewable energy sources, has led to the creation of grid codes in different countries throughout the world. These codes establish operational requirements for wind farms to enhance the maximum integration of wind energy electrical systems and to make this generation process to occur in the same way as conventional plants. Among all the technologies implemented in generating electricity from wind resource, the doubly-fed induction generator has experienced an unprecedented boom thanks to its ability to control active and reactive power delivered to the network. This thesis develops a genetic algorithm for optimal management of reactive power in power systems with wind energy. The here considered reactive power generating units are static devices of reactive power compensation and doubly fed induction wind turbines, which are used to control the voltage and the voltage stability along the network. The proposed optimization strategies will enable not only to determinate in an optimal way the reactive power compensation units location, but also to manage the reactive power injection to fulfill the needs of different scenarios of load and generation in power systems. Finally, the benefits associated with the optimal implementation of reactive power generation units in the system will be verified in terms of network security standards

Spatial distribution of HD-EMG improves identification of task and force in patients with incomplete spinal cord injury

Background: Recent studies show that spatial distribution of High Density surface EMG maps (HD-EMG) improves the identification of tasks and their corresponding contraction levels. However, in patients with incomplete spinal cord injury (iSCI), some nerves that control muscles are damaged, leaving some muscle parts without an innervation. Therefore, HD-EMG maps in patients with iSCI are affected by the injury and they can be different for every patient. The objective of this study is to investigate the spatial distribution of intensity in HD-EMG recordings to distinguish co-activation patterns for different tasks and effort levels in patients with iSCI. These patterns are evaluated to be used for extraction of motion intention.; Method: HD-EMG was recorded in patients during four isometric tasks of the forearm at three different effort levels. A linear discriminant classifier based on intensity and spatial features of HD-EMG maps of five upper-limb muscles was used to identify the attempted tasks. Task and force identification were evaluated for each patient individually, and the reliability of the identification was tested with respect to muscle fatigue and time interval between training and identification. Results: Three feature sets were analyzed in the identification: 1) intensity of the HD-EMG map, 2) intensity and center of gravity of HD-EMG maps and 3) intensity of a single differential EMG channel (gold standard).; Results show that the combination of intensity and spatial features in classification identifies tasks and effort levels properly (Acc = 98.8 %; S = 92.5 %; P = 93.2 %; SP = 99.4 %) and outperforms significantly the other two feature sets (p < 0.05).; Conclusion: In spite of the limited motor functionality, a specific co-activation pattern for each patient exists for both intensity, and spatial distribution of myoelectric activity. The spatial distribution is less sensitive than intensity to myoelectric changes that occur due to fatigue, and other time-dependent influences.Peer ReviewedPostprint (published version

Prediction of isometric motor tasks and effort levels based on high-density EMG in patients with incomplete spinal cord injury

Objective. The development of modern assistive and rehabilitation devices requires reliable and easy-to-use methods to extract neural information for control of devices. Group-specific pattern recognition identifiers are influenced by inter-subject variability. Based on high-density EMG (HD-EMG) maps, our research group has already shown that inter-subject muscle activation patterns exist in a population of healthy subjects. The aim of this paper is to analyze muscle activation patterns associated with four tasks (flexion/extension of the elbow, and supination/pronation of the forearm) at three different effort levels in a group of patients with incomplete Spinal Cord Injury (iSCI). Approach. Muscle activation patterns were evaluated by the automatic identification of these four isometric tasks along with the identification of levels of voluntary contractions. Two types of classifiers were considered in the identification: linear discriminant analysis and support vector machine. Main results. Results show that performance of classification increases when combining features extracted from intensity and spatial information of HD-EMG maps (accuracy = 97.5%). Moreover, when compared to a population with injuries at different levels, a lower variability between activation maps was obtained within a group of patients with similar injury suggesting stronger task-specific and effort-level-specific co-activation patterns, which enable better prediction results. Significance. Despite the challenge of identifying both the four tasks and the three effort levels in patients with iSCI, promising results were obtained which support the use of HD-EMG features for providing useful information regarding motion and force intentionPeer ReviewedPostprint (author's final draft

Xaperones bacterianes per millorar la producció de proteïnes a cèl·lules d'insecte

La possibilitat d'obtenir proteïnes amb aplicacions industrials o terapèutiques mitjançant la tecnologia del DNA recombinant ha revolucionat la indústria biotecnològica. Malgrat això, la producció de proteïnes recombinants en sistemes heteròlegs encara no està optimitzada, i moltes vegades aquestes proteïnes s'obtenen en forma insoluble. La selecció d'un sistema d'expressió adequat és important per aconseguir obtenir la proteïna en una forma funcional i soluble. En aquesta tesi s'ha utilitzat una GFP recombinant com a proteïna model per a estudiar l'agregació i activitat durant la producció de proteïnes recombinants en Escherichia coli i en el sistema d'expressió de baculovirus.La posibilidad de obtener proteínas con aplicaciones industriales o terapéuticas mediante la tecnología del DNA recombinante ha revolucionado la industria biotecnológica. A pesar de esto, la producción de proteínas recombinantes en sistemas heterólogos aún no está optimizada y, muchas veces, estas proteínas se obtienen en forma insoluble. La selección de un sistema de expresión adecuado es importante para conseguir obtener la proteína en una forma funcional y soluble. En esta tesis se ha utilizado una GFP recombinante como proteína modelo para estudiar agregación y actividad durante la producción de proteínas recombinantes en Escherichia coli y en el sistema de expresión de baculovirus.Recombinant DNA technology boosted the production of recombinant proteins with industrial or therapeutic applications, which transformed biotechnological industry. Despite this, recombinant protein production in heterologous systems is not yet optimized, and these proteins are often obtained as insoluble deposits. Choice of an appropriate expression system is important for proteins to be produced in a soluble and functional form. In this thesis, a recombinant GFP has been used as a model protein to study aggregation and biological activity during recombinant protein production in Escherichia coli and the baculovirus expression system

Knowledge of the concepts of 'black spot', 'grey spot' and 'high accident concentration sections' among drivers

One of the major problems related to road injuries and deaths are the presence of Black Spots. This problem has received a growing amount of attention from road managers thorough last decades, taking into account its importance for the safety of road users. In fact, knowledge about these strategic areas among drivers seems to be quite important, since this conceptualization may affect their behavior and assumed risks on the road. The main objective of this research was to assess the knowledge that drivers have on the concept of black spot and other closely related terms: 'grey spot' and 'high accident concentration sections'. For this study, it was used a random sample of 200 drivers from the province of Valencia (Spain), between 18 and 64 years of age. Through data analysis it was found that, while most of drivers does know the concept of black spot properly (87.5% of them), this trend is not stable when knowledge of related concepts is assessed. In regard to the further technical terms addressed by this study (grey spot and high accident concentration sections), there is an elevated relative percentage of drivers who have very biased misconceptions about these concepts. With respect to the 'grey spots', in which knowledge barely reached 13% of the driving population, unfamiliarity rate increased significantly. As conclusion, in regard to the concept of 'high accident concentration sections', it was found that it is a really misunderstood, relativized and biased concept among population of drivers and, furthermore, in general, unknown to most of road users. Finally, it has been suggested that the public administrations should work to increase this knowledge, as it would allow drivers to adopt more cautious behavior when confronted with this potentially dangerous sections throughout their routes