Assessment on the Efficiency of an Active Solar Thermal Facade: Study of the Effect of Dynamic Parameters and Experimental Analysis When Coupled/Uncoupled to a Heat Pump

The building sector presents poor performance in terms of energy efficiency and is looking for effective alternatives aimed at reducing the use of fossil fuels. The facade is a key element able to harness renewable energy as an Active Solar Thermal Facade (ASTF). The main purpose of this study is the assessment of a novel design concept based on a steel sandwich panel technology. The performance of the active system will be first addressed by a parametric study in order to analyze its behavior and secondly, by describing a real case based on an experimental test by connecting the active panels to a heat pump. The study shows the impact of solar irradiation and mass flow on the thermal jump achieved, while ambient and fluid inlet temperatures are the most influencing parameters in the efficiency of the facade. When coupled to the heat pump, results from a measurement campaign demonstrate a remarkable improvement in the performance of the ASTF. The results presented provide significant proof about the benefits of a synergetic combination of both technologies—solar facades and heat pumps—as efficient alternatives for the building sector, aiming to improve energy efficiency as well as reduce their dependence on non-renewable sources.This research was partially funded by the Basque Government through IT781-13 and IT1314-19 research groups and by the University of the Basque Country UPV/EHU through PES17/25. Additionally, TECNALIA Research & Innovation supported the research activities research through a cooperation agreement (PT10516) with UPV/EHU

Estado del arte en procesos de zonificacion

Los procesos de partición espacial implican la división de un espacio geográfico en diferentes unidades o zonas según un conjunto específico de criterios. En ámbitos relacionados con las ciencias geoespaciales, la delimitación de estas zonas se realiza por agrupación de otras unidades básicas de área existentes en el espacio de trabajo. En este artículo se ofrece una revisión de los métodos de solución diseñados para este tipo de problemas, comenzando por una introducción a las técnicas heurísticas y modelos matemáticos más utilizados desde los años 60, para finalizar describiendo los recientes algoritmos aplicados a diagramas de Voronoi. También se revisan las aplicaciones en las que se han implementado algunos de estos modelos, quedando patente que son herramientas diseñadas para el tratamiento de problemas específicos, dada la dificultad de diseñar modelos genéricos y versátiles para este tipo de particiones espaciales o zonificacione

Determinantes sociales de la salud en la tasa de mortalidad por Covid 19 en ciudadanos de Lima, 2020-2022

La presente tesis se desarrolló con el objetivo general de determinar la influencia de los determinantes sociales de la salud en la tasa de mortalidad por Covid-19 en los Ciudadanos de Lima, 2020-2022, empleó el enfoque cuantitativo, tipo de investigación básica, diseño no experimental, de tipo explicativa, causal, descriptivo, método hipotético deductivo. Resultado principal, el 25% de los Ciudadanos encuestados perciben alto nivel de influencia de los determinantes sociales de la salud en la tasa demortalidad por Covid 19, seguido del 8.3% quienes perciben moderado nivel influencia de los determinantes sociales de la salud en la tasa de mortalidad por Covid-19. Asimismo, en la dimensión sociopolítica y económica el 32.8% perciben bajo nivel, el 22.2% perciben moderado nivel y el 45% perciben alto nivel; en la dimensión estructural, el 33.3% perciben bajo nivel, el 23.9% perciben moderado nivel y el 42.8% perciben alto nivel y, en la dimensión intermedios, el 13.9% perciben bajo nivel, el 43.9% perciben moderado nivel y el 42.2% perciben alto nivel en las dimensiones de las determinantes sociales de la salud en los Ciudadanos de Lima, 2020-2022.Conclusiones, los determinantes sociales de la salud tienen influencia significativa en la tasa de mortalidad por la Covid19 de acuerdo con el coeficiente Wald > 4.00 (6.796 > 4.00) además p_valor < 0.05. Así como también, las dimensiones determinantes sociales, políticos y económicos, estructural e intermedios influenciaron significativamente en la tasa de mortalidad por Covid19 en los Ciudadanos de Lima, 2020-2022

Mathematical Modeling Of Cell Migration

Cell migration is an essential process, involved in immune defense, cancer spread, wound healing, and embryo development. This work presents modeling efforts to understand various mechanisms of cell migration. We first discuss the modeling of bleb-driven cell migration, where the cell membrane detaches from the cytoskeleton and generates a protrusion that is completely devoid of structural proteins. Cell migration in this case is driven essentially by pressure and motor contractility exerted by myosin. I will introduce a stochastic model of bleb-driven migration offering support for theories on blebbing cell polarization and the potential involvement of water channels. We then turn to the involvement of ion channels and ionic electrodiffusion in cell processes, first in cell volume control, and then in cell migration, presenting a model that combines electrodiffusion-driven migration with a mechanical model of actin polymerization

Evaluación de la vulnerabilidad de sistemas eléctricos por medio de programación multinivel: una revisión bibliográfica

Vulnerability studies can identify critical elements in electric power systems in order to take protective measures against possible scenarios that may result in load shedding, which can be caused by natural events or deliberate attacks. This article is a literature review on the latter kind, i.e., the interdiction problem, which assumes there is a disruptive agent whose objective is to maximize the damage to the system, while the network operator acts as a defensive agent. The non-simultaneous interaction of these two agents creates a multilevel optimization problem, and the literature has reported several interdiction models and solution methods to address it. The main contribution of this paper is presenting the considerations that should be taken into account to analyze, model, and solve the interdiction problem, including the most common solution techniques, applied methodologies, and future studies. This literature review found that most research in this area is focused on the analysis of transmission systems considering linear approximations of the network, and a few interdiction studies use an AC model of the network or directly treat distribution networks from a multilevel standpoint. Future challenges in this field include modeling and incorporating new defense options for the network operator, such as distributed generation, demand response, and the topological reconfiguration of the system.f the system.Los estudios de vulnerabilidad pueden identificar elementos críticos en los sistemas de distribución de potencia eléctrica con el fin de tomar medidas de protección contra posibles escenarios que pueden resultar en desconexión de carga (también llamado deslastre de carga), que puede ser ocasionada por eventos naturales o ataques deliberados. Este artículo es una reseña bibliográfica sobre el segundo tipo de casos, es decir, los del problema de interdicción, en el que se asume la existencia de un agente disruptivo cuyo objetivo es maximizar los daños ocasionados al sistema mientras el operador de red actúa como agente de defensa del mismo. La interacción no simultánea de estos dos agentes crea un problema de optimización multinivel y en la bibliografía se reportan varios modelos de interdicción y soluciones para abordar el problema. La contribución principal de este artículo es la presentación de consideraciones que deben tomarse en cuenta para analizar, modelar y resolver el problema de la interdicción, incluyendo las soluciones, métodos y técnicas más comunes para solucionarlo, así como futuros estudios al respecto. Esta revisión encontró que la mayoría de la investigación en el tema se enfoca en el análisis de los sistemas de transmisión, considerando las aproximaciones lineales de la red; algunos estudios en interdicción usan un modelo AC de la red o tratan las redes de distribución directamente desde un enfoque multinivel. Algunos retos en este campo son el modelado y la inclusión de nuevas opciones de defensa para el operador de la red, como la generación distribuida, la respuesta a la demanda y la reconfiguración topológica del sistema.&nbsp

Revisión de Metodologías de Arranque Óptimo de Generación para el Restablecimiento de Sistemas de Potencia Considerando Fuentes de Energía Convencionales y Renovables No Convencionales

After a large-scale blackout power system restoration must be accomplished as soon as possible. For this, the generation must be initially restored, then the transmission system, and finally the load pick up must be completed. To obtain a faster restoration process, it is necessary to establish start-up methodologies for generating units that first start those units that provide black start, and then take the starting power to other generation units without this characteristic, by means of a feasible transmission route. This paper presents a review of different methodologies of optimal generation start-up for power system restoration reported in the scientific literature taking into account the integration of non-conventional renewable energy sources. Within this review it is highlighted that heuristic methods, despite of being effective, are not used in real-time operation due to their high computational cost.Después de un apagón a gran escala, el restablecimiento del Sistema Eléctrico de Potencia (SEP) debe realizarse rápidamente. Para ello, se debe restablecer el parque de generación, el sistema de transmisión y finalmente, la demanda desatendida. Para obtener un proceso acelerado de restablecimiento es necesario establecer metodologías de arranque de unidades de generación que pongan en marcha primero las unidades con arranque en negro y después se les lleve potencia de arranque a otras unidades de generación sin esta característica, mediante una ruta de transmisión factible. En este artículo se presenta una revisión de diferentes metodologías de arranque óptimo de generadores para el restablecimiento del SEP reportadas en la literatura científica teniendo en cuenta la integración de fuentes de energía renovables no convencionales. Dentro de esta revisión se destaca que los métodos heurísticos aunque son efectivos, no se utilizan en la operación de tiempo real por su alto costo computacional

Caloric restriction, physical exercise, and CB1 receptor blockade as an efficient combined strategy for bodyweight control and cardiometabolic status improvement in male rats

Obesity is critically associated with the development of insulin resistance and related cardiovascular and kidney diseases. Several strategies for weight loss have been developed but most of them exhibit a post-intervention rebound effect. Here, we aimed to design combined weight-loss strategies of caloric restriction, physical exercise, and administration of a CB1 receptor blocker to inhibit food intake that also accomplish the objectives of lost-weight maintenance and improvement of cardiovascular and renal function. Diet-induced obesity (DIO) was generated in Sprague Dawley rats for 12 weeks to test the effects of single or combined strategies (i.e. caloric restriction, mixed training protocol, and/or administration of appetite suppressant) on caloric intake, body weight, cardiovascular and renal functionality resulting from a weight-loss intervention period of 3 weeks followed by 6 weeks of weight maintenance. Consumption of a high-fat diet (HFD) caused a significant increase in body weight (5th week of the experimental period) and led to the development of insulin resistance, cardiovascular, and renal alterations. The different interventions tested, resulted in a significant body weight loss and improved glucose metabolism, aerobic capacity, electrocardiographic parameters, vascular expression of adhesion molecules and inflammatory mediators, and renal functionality, reaching values similar to the control normocaloric group or even improving them. Successful maintenance of lost weight was achieved along a 6-week maintenance period in addition to adequate health status. In conclusion, the weight-loss and maintenance intervention strategies tested were efficient at reversing the obesity-related alterations in body weight, glucose metabolism, aerobic capacity, cardiovascular and renal functionality. The beneficial action was very consistent for caloric restriction and physical exercise, whereas administration of a CB1 receptor blocker complemented the effects of the prior interventions in some parameters like body weight or aerobic capacity, and showed specific actions in renal status, increasing glomerular filtration rate and diuresis. Overall, the novelty of our study relies on the easy implementation of combined strategies for effective weight management that resulted in significant health benefits.Spanish Ministry of Science, Innovation and UniversitiesEuropean Commission DEP2014-58296-R RTC-2017-6540-1 RTI2018-100934-B-I00European Commissio

Non-linear classifiers applied to EEG analysis for epilepsy seizure detection

This work presents a novel approach for automatic epilepsy seizure detection based on EEG analysis that exploits the underlying non-linear nature of EEG data. In this paper, two main contributions are presented and validated: the use of non-linear classifiers through the so-called kernel trick and the proposal of a Bag-of-Words model for extracting a non-linear feature representation of the input data in an unsupervised manner. The performance of the resulting system is validated with public datasets, previously processed to remove artifacts or external disturbances, but also with private datasets recorded under realistic and non-ideal operating conditions. The use of public datasets caters for comparison purposes whereas the private one shows the performance of the system under realistic circumstances of noise, artifacts, and signals of different amplitudes. Moreover, the proposed solution has been compared to state-of-the-art works not only for pre-processed and public datasets but also with the private datasets. The mean F1-measure shows a 10% improvement over the second-best ranked method including cross-dataset experiments. The obtained results prove the robustness of the proposed solution to more realistic and variable conditions. (C) 2017 Elsevier Ltd. All rights reserved