Surrogate-based optimization of tidal turbine arrays: a case study for the Faro-Olhão inlet

This paper presents a study for estimating the size of a tidal turbine array for the Faro-Olhão Inlet (Potugal) using a surrogate optimization approach. The method compromises problem formulation, hydro-morphodynamic modelling, surrogate construction and validation, and constraint optimization. A total of 26 surrogates were built using linear RBFs as a function of two design variables: number of rows in the array and Tidal Energy Converters (TECs) per row. Surrogates describe array performance and environmental effects associated with hydrodynamic and morphological aspects of the multi inlet lagoon. After validation, surrogate models were used to formulate a constraint optimization model. Results evidence that the largest array size that satisfies performance and environmental constraints is made of 3 rows and 10 TECs per row.Eduardo González-Gorbeña has received funding for the OpTiCA project (http://msca-optica.eu/) from the Marie Skłodowska-Curie Actions of the European Union's H2020-MSCA-IF-EF-RI-2016 / GA#: 748747. The paper is a contribution to the SCORE pro-ject, funded by the Portuguese Foundation for Science and Technology (FCT–PTDC/AAG-TEC/1710/2014). André Pacheco was supported by the Portuguese Foun-dation for Science and Technology under the Portuguese Researchers’ Programme 2014 entitled “Exploring new concepts for extracting energy from tides” (IF/00286/2014/CP1234).info:eu-repo/semantics/publishedVersio

Analysis of the efficiency of wind turbine gearboxes using the temperature variable

The aim of this paper is to evaluate how lubricant selection affects gearbox efficiency and overall energy production by analysing real data from wind farms, monitored and controlled by a Supervisory Control and Data Acquisition (SCADA system). The turbines analysed worked with two or more oil types for the same amount of hours, which allowed to establish relations between the active power curves and wind velocity; oil temperature inside gearboxes and wind velocity; and oil temperature inside gearboxes and active power production. The results of this study evidenced a direct relation between oil characteristics and energy efficiency i.e. gearboxes working with mineral oil perform better then gearboxes working with synthetic oils. Those differences can be significant in terms of active power production. Also, it was observed oil degradation as function of temperature increase, with changes on viscosity, which reveals that temperature behaviour along the active power curve is strongly related to oil' characteristics. (C) 2018 Elsevier Ltd. All rights reserved.Agência financiadora Portuguese Foundation for Science and Technology (FCT) PTDC/AAG-TEC/1710/2014 MONITOR project - Atlantic Area EAPA_333/2016 Portuguese Foundation for Science and Technology under the Portuguese Researchers' Programme 2014 IF/00286/2014/CP1234 Marie Sklodowska-Curie Actions of the European Union's H2020-MSCA-IF-EF-RI-2016/under REA - 748747info:eu-repo/semantics/publishedVersionhttp://creativecommons.org/licenses/by/4.0

Marine energy prototype testing at Ria Formosa

Economic growth and increasing human demands are among the most important factors for growing world energy consumption. Energy is present in everything around us: it is a property of all objects and is essential to life. We find various forms of energy in the world around us. When plants grow, for example, they are converting sunlight energy into chemical energy in the form of carbohydrates and other compounds stored in your body (e.g. sugars). The form of energy that man uses most today is the chemical energy contained in fossil fuels, such as oil, coal and natural gas. About 80% of the energy we use comes from these sources. However, these sources are very polluting, since their use releases substances harmful to the environment and to public health. An example of this is the increased concentration of greenhouse gases such as carbon dioxide (CO2) in the atmosphere, which is a cause of climate change. In addition to pollutants, these sources of energy are non-renewable, which means that they are being consumed at a faster rate than is necessary for their production, so their availability is decreasing. Due to the increasing oil and natural gas prices, reduced fuel reserves and the requirement for reduced CO2 emissions to avert climate change, the use of alternative energy sources is both financially unavoidable and environmentally preferable (UN, 2015). Hence, generating renewable energy is nowadays one of the most relevant endeavours for research. Countries worldwide now recognise the need to incorporate renewable energy resources in their energy policy as an alternative to finite fossil fuel resources in order to achieve future energy security and to mitigate the effects of climate change induced by human activities. Today, renewable energy is now firmly entrenched as the world's fastest growing energy sector (IEA, 2017).info:eu-repo/semantics/publishedVersio

Reflexión estratégica sobre Airlan Industrial S.A.

[spa] En este trabajo de fin de grado se propone una reflexión estratégica personal en torno a la empresa Airlan Industrial, S.A., en la que efectué mi estancia en el itinerario dual del Grado en Administración y Dirección de Empresa, que me ha servido como caso de estudio en este ejercicio. Para ello he utilizado distintas herramientas propias de la dirección estratégica que hemos trabajado a lo largo de los estudios del grado, como son: el análisis PESTEL, las Cinco fuerzas de Porter, el análisis de los recursos y capacidades, la matriz DAFO y la propuesta de líneas estratégicas.[eus] Gradu amaierako lan honetan Airlan Industrial, S.A. enpresari buruzko hausnarketa estrategiko pertsonala egiten da. Enpresa horretan Enpresen Administrazio eta Zuzendaritza Graduko ibilbide dualean egin nuen egonaldia adibide gisa erabili dudalarik. Horretarako, graduaren ikasketetan landu dugun zuzendaritza estrategikoari dagozkion hainbat tresna erabili ditut: PESTEL analisia, Porterren Bost indarrak, baliabideen eta gaitasunen azterketa, AMIA matrizea eta ildo estrategikoen proposamena.[eng] In this end-of-degree project, a personal strategic reflection is made about the company Airlan Industrial, S.A., in which I have done my internship in the dual itinerary of the Degree in Business Administration and Management and which has served me as a case study in this exercise. To do this, I have used different tools of strategic management that we have worked throughout the studies of the degree, such as: the PESTEL analysis, Porter's Five Forces, the analysis of resources and capabilities, the SWOT matrix and the proposal of strategic line

Dialogamos de sexo en la escuela

Proyecto interdisciplinario de Educación Sexual desarrollado a traves de talleres en todos los años y divisiones de la Escuela normal "Ramón J. Cárcano" de la Ciudad de Monte Caseros, Corrientes durante el ciclo lectivo 2008 . La áreas involucradas fuerosn Ciencias Naturales,Educación Física,Educación Artística y Matematica. Se realizó un diagnóstico a partir de una encuasta anónima individual a cada alumno participante de los talleres, la misma nos sirvió pra trabajar preconceptos sobre Educación Sexual que poseen los alumnos. A partir de alli se realizarón varios encuentros donde a través de juegos de comunicación , de contacto corporal con música figuras ,representaciones se abordaron contenidos conceptuales ,procedimentales y actitudinales que permiten educacar en sexualidad apuntando al desarrollo integral del individuo

Influencia de las votaciones en la elección social

En este trabajo, se tratarán los distintos tipos de votaciones y cómo éstas influyen en la elección social. Se analizarán desde dos puntos de vista: primero, con qué precisión se representan en la votación las preferencias de los votantes, y segundo, cómo de manipulables son estos métodos

Calidad de atención y satisfacción personal en pacientes de salud mental de un hospital del Cusco, 2022

Se realiza esta investigación, con el objeto de lograr: Determinar la relación entre Calidad de atención y satisfacción personal en pacientes de Salud Mental de un Hospital del Cusco. La metodología fue de enfoque cuantitativo, pues precisa el grado de relación existente entre sus variables, midiéndose estas variables y posteriormente verificar las hipótesis estadísticamente. Con diseño de tipo correlacional, no experimental, puesto que la variable independiente no sufrirá modificación intencional, recolectando datos propios de la realidad. Por su temporalidad es transversal, realizándose la recopilación de la información en un periodo de tiempo corto, con una muestra constituida por 100 usuarios. La encuesta fue utilizada como técnica, con el fin de obtener la opinión de una población determinada referente al problema en cuestión y como instrumento se hizo el uso de un cuestionario en la escala de Likert, consistiendo este en un conjunto de interrogantes realizados para conocer la opinión que tiene cada uno de los pacientes, concluyéndose al finalizar, que hay la existencia de una significativa y directa relación entre calidad de atención y satisfacción personal en los usuarios que recurren al hospital regional del Cusco; teniendo un coeficiente de correlación, Rho de Spearman 0.77, el mismo que es inferior a α = 0.05; por lo que se acepta la hipótesis alterna y rechaza la hipótesis nula

Influencia del campo magnético variable de onda sinusoidal de 10 – 50 KHz y de intensidades comprendidas entre 10 -100 miliGauss sobre el crecimiento de Lactobacillus plantarum utilizado como probiótico en alimentos

El campo magnético puede provocar efectos dañinos o beneficiosos sobre los sistemas biológicos de todos los seres vivos. El uso de dicha radiación como tratamiento magnético puede aplicarse en la modalidad de campo magnético estático u oscilante, es decir, un campo magnético que oscila según la frecuencia de la corriente eléctrica que lo induce en KHz. Las frecuencias menores de 3 KHz se clasifican como frecuencias extremadamente bajas (Paunesku T, 2007). Los efectos del tratamiento magnético sobre los microorganismos se clasifican en no observables, inhibitorios o estimulantes, dependiendo de la densidad del campo magnético (CM) expresada en teslas (T) o en gauss (G), así como de la frecuencia de la corriente eléctrica que lo indujo, si es oscilante, y del tiempo de exposición (Barbosa G, 2000).Trabado de investigació

An evaluation of offshore wind power production by floatable systems: a case study from SW Portugal

The challenge for floating offshore wind structures is to reduce costs. The industry needs a wind turbine support solution that can be fabricated and deployed from existing shipyards and port facilities, while investors need accurate estimations and forecasts of wind resources and quantified information on the inherent variability in wind power generation. This paper merges hindcast model data with observed in situ data to characterize the wind resource potential off the SW coast of Portugal. The validation procedure adopted allows an estimation of the coefficient used for power-law extrapolation of the wind measurements and a reduction in the uncertainty of the power density calculations. Different types of turbine model are compared and site metocean characteristics are examined as a basis for choosing between existing wind floatable solutions. The calculations using four different wind turbine models indicate a preferable installed capacity of 3-4 MW for a hub height of 90-120 m (i.e., representing the best capacity factor and load hours). There is a consistent difference in power density of about 20% from a location 5 nautical miles (NM) offshore to one 10 NM offshore, which represents an increment of 20% -25% in energy production depending on the particular wind turbine capacity factor. (C) 2017 Elsevier Ltd. All rights reserved.Portuguese Foundation for Science and Technology [FCT - PTDC/AAG-TEC/1710/2014]Portuguese Foundation for Science and Technology under the Portuguese Researchers' Programme [IF/00286/2014/CP1234]Portuguese Foundation for Science and Technology Investigator Programme [IF/01142/2015

Assessing the effects of Tidal Energy Converter array size on hydrodynamics of Ria Formosa (Portugal)

info:eu-repo/semantics/publishedVersio