522 research outputs found
Data Science and Big Data in Energy Forecasting
This editorial summarizes the performance of the special issue entitled Data Science and Big Data in Energy Forecasting, which was published at MDPI’s Energies journal. The special issue took place in 2017 and accepted a total of 13 papers from 7 different countries. Electrical, solar and wind energy forecasting were the most analyzed topics, introducing new methods with applications of utmost relevance.Ministerio de Competitividad TIN2014-55894-C2-RMinisterio de Competitividad TIN2017-88209-C2-
The Dionysean-apollonian composition of Goethe’s promethean idea, in the form of feeling and thought
Utilizando el pensamiento expuesto la obra El Origen de la Tragedia, de Friedrich
Nietzsche, en particular lo relacionado con los dioses Apolo y Dionisios, se analizan los
componentes dionisíacos y apolíneos en la evolución de lo prometeico en la obras poéticas
Prometeo, Límites de lo humano, Lo divino y Uno y todo, de Johann Wolfgang von
GoetheUsing the ideas articulated in Friedrich Nietzsche's The Birth of Tragedy, especially
those related to the gods Apollo and Dionysus, the present essay analyzes the Dionysian
and Apollonian elements of the evolution of the Promethean idea in Johann Wolfgang von
Goethe's poetic works Prometheus, The Boundaries of Humanity, The Godlike, and One
and Al
A novel ensemble method for electric vehicle power consumption forecasting: Application to the Spanish system
The use of electric vehicle across the world has become one of the most challenging issues for environmental policies. The galloping climate change and the expected running out of fossil fuels turns the use of such non-polluting cars into a priority for most developed countries. However, such a use has led to major concerns to power companies, since they must adapt their generation to a new scenario, in which electric vehicles will dramatically modify the curve of generation. In this paper, a novel approach based on ensemble learning is proposed. In particular, ARIMA, GARCH and PSF algorithms' performances are used to forecast the electric vehicle power consumption in Spain. It is worth noting that the studied time series of consumption is non-stationary and adds difficulties to the forecasting process. Thus, an ensemble is proposed by dynamically weighting all algorithms over time. The proposal presented has been implemented for a real case, in particular, at the Spanish Control Centre for the Electric Vehicle. The performance of the approach is assessed by means of WAPE, showing robust and promising results for this research field.Ministerio de Economía y Competitividad Proyectos ENE2016-77650-R, PCIN-2015-04 y TIN2017-88209-C2-R
Undershoot and order quantity probability distributions in periodic review, reorder point, order-up-to-level inventory systems with continuous demand
The undershoot of the reorder point in the periodic review, order-up-to-level (R, s, S) inventory system is known to follow a complex probability distribution which depends on the value of S-s (Δ) and the distribution of the demand during the review interval (R). We focus on the continuous demand case with full backlogging and variable lead-time. For this case, a generic formulation of the undershoot probability density function (p.d.f.) is developed. The order quantity probability distribution in (R, s, S) systems is the same as the undershoot probability distribution with a shift of Δ in the random variable. Therefore, the latter opens the possibility of calculating valuable managerial information such as the expected average order quantity, its standard deviation, and the probability that the order quantity is lower than or exceeds a predetermined value. Based on the proposed formulation, we derive an analytical expression of the undershoot p.d.f. (and hence the order quantity p.d.f.) for the case of gamma distributed demand, as well as a tractable approximation for the normal distributed demand. Both expressions are shown to be dependent upon two nondimensional parameters, Δ/μR and the coefficient of variation, with the mean demand during the review interval (μR) acting as a scale parameter. We thus define a nondimensional undershoot p.d.f. (NUPDF). The relevance of full nondimensionalization stems from the fact that gamma and normal NUPDF analyses can be scaled to any case of gamma and normal distributed demands. Although we focus on the inventory management viewpoint, the results for the gamma distributed case can be directly adapted for use in any renewal process.The authors would like to acknowledge the Spanish Agencia Estatal de Investigacion, for the support provided throughout the research project code RTI2018-094614-B-I00 (SMASHING) into the "Programa Estatal de I+D+i Orientada a los Retos de la Sociedad"
Partitioning-Clustering Techniques Applied to the Electricity Price Time Series
Clustering is used to generate groupings of data from a large dataset, with the intention of representing the behavior of a system as accurately as possible. In this sense, clustering is applied in this work to extract useful information from the electricity price time series. To be precise, two clustering techniques, K-means and Expectation Maximization, have been utilized for the analysis of the prices curve, demonstrating that the application of these techniques is effective so to split the whole year into different groups of days, according to their prices conduct. Later, this information will be used to predict the price in the short time period. The prices exhibited a remarkable resemblance among days embedded in a same season and can be split into two major kind of clusters: working days and festivities
El deporte y la(s) política(s). Formas de abordar y desafíos desde la disciplina histórica en Chile
In the present article, a panoramic vision of the social and historical studies that make a relation between politics and sports is proposed; three major groups are identified, theorists, political frameworks and political sports such as network theory or the concept of instrumental friendship, which can help illuminate the phenomena explored prematurely. The vision of all this is that we are still analyzing the sport in a very static way and that it is based on the traditional conceptions of "the political", and that even more it problematizes that concept, more questions about the investigations that do it in it; that is why we choose to see the "political" as a process and not as something given, and from that point, history becomes fundamental.El presente artículo propone una visión panorámica de los estudios sociales e históricos que hacen relación entre política y deportes; en él se identifican tres grandes grupos (política institucional del deporte, relación clubes deportivos y asociaciones políticas no-estatales, y el club como política) de las cuales daremos cuenta con sus principales significaciones y variantes, sumado a entregar nuevos retos, marcos teóricos—como la teoría de redes o el concepto de amistad instrumental—que pueden ayudar a iluminar fenómenos explorados de manera prematura. La visión de todo esto, demuestra que aún estamos analizando el deporte de forma muy estática y que se basa en concepciones tradicionales de “lo político”, y que mientras más problematizamos dicho concepto, más fecundas serán las investigaciones que se basen en ello; es por eso que se opta por ver lo “político” como un proceso y no como algo dado, y desde ese punto la historia se vuelve fundamental
Estudio de líneas de manipulación de fruta de hueso y cítricos con ayuda de frutos electrónicos
Se emplearon dos frutos electrónicos simulados IS-lOO de diferente tamaño (grande: 300.6 g y 8.8 cm de diámetro; pequeño: 114.7 g y 6.2 cm de diámetro) para evaluar la calidad de las operaciones de post-recolección. Con la ayuda de los frutos electrónicos IS-100 es posible detectar en qué lugar y con qué intensidad se produce un impacto, 'así como el tipo de material contra el que estos frutos están impactando. Se estudiaron cuatro líneas de manipulación en varias cooperativas (dos de fruta de hueso y dos de cítricos). En la mayoría de puntos de transferencia se registran impactos con intensidades superiores a 50 g's. Los impactos registrados en las líneas de manipulación de cítricos son mayores que los correspondientes a las líneas de fruta de hueso. Para estudiar el efecto de las líneas sobre diferentes variedades de las especies manipuladas en ellas, se diseñó un ensayo de interacción fruta-línea de manipulación, a través del cual se comparan lotes de fruta manipulados y sin manipular, cualificándose los daños atribuibles a la recolección y a la manipulación. En todos los casos estudiados, más del 50% de los frutos ya manipulados presentan algún tipo de daño. La observación de.ejstps daños al cabo de 2 días, en el caso de la fruta de hueso, y 10 días, en el caso de los cítricos, revela que estos daños evolucionan, siendo mayores y más patentes en la segunda fecha de observación
Efeitos do solo e clima numa vinha de uva de mesa com cultura de cobertura. Gestão da rega utilizando redes de sensores
[ENG] TThe use of mulches in vineyards and orchards is a traditional agricultural practice used with the aim of saving moisture, reducing weed growth and improving organic matter content in the soil. In table grape vineyards trained to overhead system in Puglia region (Southeastern Italy), plastic sheets covering the canopy are often used to either advance ripening or delay harvest. In this environment, the living mulches could contribute to the modification of the microclimate around the canopy below the plastic sheets. This condition has an influence on the climatic demand and on both the vegetative and productive activities, mainly in stages with a high evapotranspiration. However, the presence of living mulches could increase the demand of available water and nutrient resources and this could cause a lower yield. The aim of this study was to acquire a suitable knowledge to manage irrigation and verify the influences of living mulches on the vine by using wireless sensor networks to measure the vapor pressure deficit, soil water potential and content.[POR] A utilização de coberturas do solo em vinhas e pomares é uma prática agrícola tradicional, utilizada com o objetivo de preservar a humidade do solo, reduzir o crescimento de infestantes e melhorar o teor de matéria orgânica no solo. Em vinhas de uva de mesa, conduzidas em sistema de pérgula na região de Puglia (sudeste da Itália), são frequentemente usadas coberturas de plástico para promover o avanço da maturação ou o atraso da colheita. Neste ambiente a utilização de enrelvamentos pode contribuir para a modificação do microclima do copado. Esta condição pode influenciar a demanda atmosférica, bem como a atividade vegetativa e reprodutiva da videira, principalmente em períodos de elevada evapotranspiração. No entanto, a presença do enrelvamento pode originar um aumento da demanda dos recursos disponíveis, nomeadamente água e nutrientes, o que poderá provocar uma quebra de produção. O objetivo deste estudo foi adquirir conhecimento para a gestão da rega e, simultaneamente, verificar a influência dos enrelvamentos na atividade da videira, usando para o efeito redes de sensores “sem fio” para medir o déficit de pressão de vapor, o potencial e o conteúdo de água no solo.The development of this work was supported by: The Spanish Ministry of Science and Innovation through the project RIDEFRUT (ref. AGL2013-49047-C2-1-R), the “Fundacion Seneca, Agencia de Ciencia y Tecnologia” of the Region of Murcia under the “Excelence Group Program”, and the Technical University of Cartagena under the PMPDI Program
Afrontamiento psicológico de los procedimientos médicos invasivos y dolorosos aplicados para el tratamiento del cáncer infantil y adolescente: la perspectiva cognitivo-conductual
El afrontamiento psicológico del cáncer infantil implica el uso de estrategias y recursos que ayuden al niño y a su familia a vivenciar la enfermedad con la menor afectación emocional y comportamental posible. En este sentido, desde la Psicología se han desarrollado y adaptado técnicas y programas con el objetivo de minimizar el impacto psicológico que implica el diagnóstico y tratamiento del cáncer en la infancia y la adolescencia. En el presente artículo se revisan los procedimientos psicológicos fundamentados en el paradigma cognitivo-conductual como la transmisión de información, el entrenamiento en habilidades de afrontamiento, el audiovisual, el juego, la biblioterapia y el humor, considerando su aplicación en niños y adolescentes, y el papel de los padres en la preparación.Psychological coping with childhood cancer involves the use of strategies and resources that help children and their families undergo the disease with the fewest possible emotional and behavioural problems. In the field of Psychology, techniques and programs have been developed and adapted with the aim of minimising the psychological impact of the diagnosis and treatment of childhood and adolescent cancer. The present paper reviews psychological procedures based on the cognitive- behavioural paradigm, such as transmission of information, coping skills training, the use of audiovisual materials, games, bibliotherapy, and humour. It considers the use of such procedures in children and adolescents and the role of parents in the preparation
Improving Time Series Forecasting by Discovering Frequent Episodes in Sequences
This work aims to improve an existing time series forecasting algorithm –LBF– by the application of frequent episodes techniques as a complementary step to the model. When real-world time series are forecasted, there exist many samples whose values may be specially unexpected. By the combination of frequent episodes and the LBF algorithm, the new procedure does not make better predictions over these outliers but, on the contrary, it is able to predict the apparition of such atypical samples with a great accuracy. In short, this work shows how to detect the occurrence of anomalous samples in time series improving, thus, the general forecasting scheme. Moreover, this hybrid approach has been successfully tested on electricity-related time series
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