Vertical wind profile characterization and identification of patterns based on a shape clustering algorithm

Wind power plants are becoming a generally accepted resource in the generation mix of many utilities. At the same time, the size and the power rating of individual wind turbines have increased considerably. Under these circumstances, the sector is increasingly demanding an accurate characterization of vertical wind speed profiles to estimate properly the incoming wind speed at the rotor swept area and, consequently, assess the potential for a wind power plant site. The present paper describes a shape-based clustering characterization and visualization of real vertical wind speed data. The proposed solution allows us to identify the most likely vertical wind speed patterns for a specific location based on real wind speed measurements. Moreover, this clustering approach also provides characterization and classification of such vertical wind profiles. This solution is highly suitable for a large amount of data collected by remote sensing equipment, where wind speed values at different heights within the rotor swept area are available for subsequent analysis. The methodology is based on z-normalization, shape-based distance metric solution and the Ward-hierarchical clustering method. Real vertical wind speed profile data corresponding to a Spanish wind power plant and collected by using a commercialWindcube equipment during several months are used to assess the proposed characterization and clustering process, involving more than 100000 wind speed data values. All analyses have been implemented using open-source R-software. From the results, at least four different vertical wind speed patterns are identified to characterize properly over 90% of the collected wind speed data along the day. Therefore, alternative analytical function criteria should be subsequently proposed for vertical wind speed characterization purposes.The authors are grateful for the financial support from the Spanish Ministry of the Economy and Competitiveness and the European Union —ENE2016-78214-C2-2-R—and the Spanish Education, Culture and Sport Ministry —FPU16/042

Factores predictores de supresión virológica a largo plazo en pacientes VIH y caracterización de la respuesta inmunológica

Describir los factores determinantes de supresión virológica a largo plazo en personas infectadas por el VIH tras inicio de una pauta antiretroviral supresora. Caracterizar la evolución de la respuesta inmunológica mediante la recuperación de CD4.Material y métodos: estudio de cohortes retrospectivo que incluyó a 337 pacientes que habían alcanzado la supresión virológica tras inicio de TAR y con un seguimiento posterior de al menos 10 años. Se utilizó como variable dependiente el mantener la CVS de forma continua vs discontinua en el tiempo. Resultados: de los 337 pacientes incluidos, 57 (16,91%) pacientes habían mantenido la CVS de forma continua frente a 280 (83,09%) que lo habían mantenido de forma intermitente. Se encontró que el grupo de CVS no mantenida presentaba una edad de adquisición menor (29 años vs 31años, p=0,018), mientras que era mayor el tabaquismo (83,6%vs 70,2%, p=0,018), el ser UDVP (53,1%vs 31,6%, p=0,004) y la coinfección por VHC(54,9% vs 40,9%, p=0,046). En pacientes con CVS continua no se recogió ninguna muerte (p=0,003). El análisis multivariante confirmó que el ser UDVP era un factor de riesgo para no mantener CVS de forma continua (RR 3,879 (IC 95% (1,07-14,067), p=0,003). La recuperación de CD4 fue mayor en los pacientes con CVS mantenida (350(-357 ¿ 929) vs 157(-1410- 1354), p=0,001).Conclusiones: El ser UDVP es un factor de riesgo para no mantener la carga viral suprimida. La respuesta inmunológica mediante recuperac ión de CD4 es mayor en los pacientes con CVS mantenida. Los pacientes con CVS no mantenida podrían tener mayor mortalidad

Derecho disciplinario y seguridad jurídica

La potestad sancionadora de la Administración tiene su reconocimiento constitucional en el art. 25, donde además se señala una clara limitación máxima en cuanto a la naturaleza de las sanciones a imponer, que no podrán implicar directa o subsidiariamente privación de libertad. Pero poco más ilustra el precepto al respecto. Este reconocimiento lleva implícito otro: y es el de la autosuficiencia sancionadora de la Administración que, en primera instancia, se vale por si sola para sancionar a su personal, sin necesidad de la intervención judicial. De ahí precisamente que se pueda concluir que el reconocimiento de esa potestad pone en riesgo el principio de jurisdiccionalidad de la sanción, en virtud del cual, son los juzgados y tribunales los que las imponen, ya que en el ámbito interno de la Administración, si el sancionado no recurre la sanción que le ha sido impuesta, cobrará firmeza sin intervención jurisdiccional. Por este motivo, dada la excepcionalidad que supone que las sanciones no sean impuestas por los juzgados y Tribunales, es preciso controlar esa potestad y mantenerla siempre al amparo del principio de legalidad

A Controller for Optimum Electrical Power Extraction from a Small Grid-Interconnected Wind Turbine

[EN] Currently, wind power is the fastest-growing means of electricity generation in the world. To obtain the maximum efficiency from the wind energy conversion system, it is important that the control strategy design is carried out in the best possible way. In fact, besides regulating the frequency and output voltage of the electrical signal, these strategies should also extract energy from wind power at the maximum level of efficiency. With advances in micro-controllers and electronic components, the design and implementation of efficient controllers are steadily improving. This paper presents a maximum power point tracking controller scheme for a small wind energy conversion system with a variable speed permanent magnet synchronous generator. With the controller, the system extracts optimum possible power from the wind speed reaching the wind turbine and feeds it to the grid at constant voltage and frequency based on the AC-DC-AC conversion system. A MATLAB/SimPowerSystems environment was used to carry out the simulations of the system. Simulation results were analyzed under variable wind speed and load conditions, exhibiting the performance of the proposed controller. It was observed that the controllers can extract maximum power and regulate the voltage and frequency under such variable conditions. Extensive results are included in the paper.This work was partially supported by the Spanish Ministry of Education, Culture and Sports-reference FPU16/04282.García-Sánchez, TM.; Mishra, AK.; Hurtado-Perez, E.; Puche-Panadero, R.; Fernández-Guillamón, A. (2020). A Controller for Optimum Electrical Power Extraction from a Small Grid-Interconnected Wind Turbine. Energies. 13(21):1-16. https://doi.org/10.3390/en13215809S1161321Fernández-Guillamón, A., Villena-Lapaz, J., Vigueras-Rodríguez, A., García-Sánchez, T., & Molina-García, Á. (2018). An Adaptive Frequency Strategy for Variable Speed Wind Turbines: Application to High Wind Integration Into Power Systems. Energies, 11(6), 1436. doi:10.3390/en11061436Fernández-Guillamón, A., Sarasúa, J. I., Chazarra, M., Vigueras-Rodríguez, A., Fernández-Muñoz, D., & Molina-García, Á. (2020). Frequency control analysis based on unit commitment schemes with high wind power integration: A Spanish isolated power system case study. International Journal of Electrical Power & Energy Systems, 121, 106044. doi:10.1016/j.ijepes.2020.106044Huber, M., Dimkova, D., & Hamacher, T. (2014). Integration of wind and solar power in Europe: Assessment of flexibility requirements. Energy, 69, 236-246. doi:10.1016/j.energy.2014.02.109Fernández-Guillamón, A., Martínez-Lucas, G., Molina-García, Á., & Sarasua, J.-I. (2020). Hybrid Wind–PV Frequency Control Strategy under Variable Weather Conditions in Isolated Power Systems. Sustainability, 12(18), 7750. doi:10.3390/su12187750Fernández‐Guillamón, A., Vigueras‐Rodríguez, A., & Molina‐García, Á. (2019). Analysis of power system inertia estimation in high wind power plant integration scenarios. IET Renewable Power Generation, 13(15), 2807-2816. doi:10.1049/iet-rpg.2019.0220Fernández-Guillamón, A., Das, K., Cutululis, N. A., & Molina-García, Á. (2019). Offshore Wind Power Integration into Future Power Systems: Overview and Trends. Journal of Marine Science and Engineering, 7(11), 399. doi:10.3390/jmse7110399Muñoz-Benavente, I., Hansen, A. D., Gómez-Lázaro, E., García-Sánchez, T., Fernández-Guillamón, A., & Molina-García, Á. (2019). Impact of Combined Demand-Response and Wind Power Plant Participation in Frequency Control for Multi-Area Power Systems. Energies, 12(9), 1687. doi:10.3390/en12091687Gil-García, I. C., García-Cascales, M. S., Fernández-Guillamón, A., & Molina-García, A. (2019). 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Modelling Type 1 and 2 Wind Turbines based on IEC 61400-27-1: Transient Response under Voltage Dips

[EN] Wind power plants depend greatly on weather conditions, thus being considered intermittent, uncertain and non-dispatchable. Due to the massive integration of this energy resource in the recent decades, it is important that transmission and distribution system operators are able to model their electrical behaviour in terms of steady-state power flow, transient dynamic stability, and short-circuit currents. Consequently, in 2015, the International Electrotechnical Commission published Standard IEC 61400-27-1, which includes generic models for wind power generation in order to estimate the electrical characteristics of wind turbines at the connection point. This paper presents, describes and details the models for wind turbine topologies Types 1 and 2 following IEC 61400-27-1 for electrical simulation purposes, including the values for the parameters for the different subsystems. A hardware-in-the-loop combined with a real-time simulator is also used to analyse the response of such wind turbine topologies under voltage dips. The evolution of active and reactive powers is discussed, together with the wind turbine rotor and generator rotational speeds.This work was partially supported by the Spanish Ministry of Economy and Competitiveness and the European Union -FEDER Funds, ENE2016-78214-C2-1-R-; and the Spanish Ministry of Education, Culture and Sports -ref. FPU16/04282-.García-Sánchez, TM.; Muñoz-Benavente, I.; Gómez-Lázaro, E.; Fernández-Guillamón, A. (2020). Modelling Type 1 and 2 Wind Turbines based on IEC 61400-27-1: Transient Response under Voltage Dips. Energies. 13(16):1-19. https://doi.org/10.3390/en13164078S1191316Fernández-Guillamón, A., Villena-Lapaz, J., Vigueras-Rodríguez, A., García-Sánchez, T., & Molina-García, Á. (2018). An Adaptive Frequency Strategy for Variable Speed Wind Turbines: Application to High Wind Integration Into Power Systems. Energies, 11(6), 1436. doi:10.3390/en11061436Fernández-Guillamón, A., Das, K., Cutululis, N. A., & Molina-García, Á. (2019). Offshore Wind Power Integration into Future Power Systems: Overview and Trends. Journal of Marine Science and Engineering, 7(11), 399. doi:10.3390/jmse7110399Fernández-Guillamón, A., Gómez-Lázaro, E., Muljadi, E., & Molina-García, Á. (2019). Power systems with high renewable energy sources: A review of inertia and frequency control strategies over time. Renewable and Sustainable Energy Reviews, 115, 109369. doi:10.1016/j.rser.2019.109369Cardozo, C., van Ackooij, W., & Capely, L. (2018). Cutting plane approaches for frequency constrained economic dispatch problems. Electric Power Systems Research, 156, 54-63. doi:10.1016/j.epsr.2017.11.001Fernández-Guillamón, A., Martínez-Lucas, G., Molina-García, Á., & Sarasua, J. I. (2020). An Adaptive Control Scheme for Variable Speed Wind Turbines Providing Frequency Regulation in Isolated Power Systems with Thermal Generation. Energies, 13(13), 3369. doi:10.3390/en13133369Global Wind Report 2019https://gwec.net/global-wind-report-2019/Muñoz-Benavente, I., Hansen, A. D., Gómez-Lázaro, E., García-Sánchez, T., Fernández-Guillamón, A., & Molina-García, Á. (2019). Impact of Combined Demand-Response and Wind Power Plant Participation in Frequency Control for Multi-Area Power Systems. Energies, 12(9), 1687. doi:10.3390/en12091687Villena-Ruiz, R., Lorenzo-Bonache, A., Honrubia-Escribano, A., Jiménez-Buendía, F., & Gómez-Lázaro, E. (2019). Implementation of IEC 61400-27-1 Type 3 Model: Performance Analysis under Different Modeling Approaches. Energies, 12(14), 2690. doi:10.3390/en12142690Kumar, D., & Chatterjee, K. (2016). A review of conventional and advanced MPPT algorithms for wind energy systems. 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Physica A: Statistical Mechanics and its Applications, 392(18), 4106-4120. doi:10.1016/j.physa.2013.04.038Fernández‐Guillamón, A., Vigueras‐Rodríguez, A., & Molina‐García, Á. (2019). Analysis of power system inertia estimation in high wind power plant integration scenarios. IET Renewable Power Generation, 13(15), 2807-2816. doi:10.1049/iet-rpg.2019.0220Heredia, F.-J., Cuadrado, M. D., & Corchero, C. (2018). On optimal participation in the electricity markets of wind power plants with battery energy storage systems. Computers & Operations Research, 96, 316-329. doi:10.1016/j.cor.2018.03.004Zhang, W., & Fang, K. (2017). Controlling active power of wind farms to participate in load frequency control of power systems. IET Generation, Transmission & Distribution, 11(9), 2194-2203. doi:10.1049/iet-gtd.2016.1471Honrubia-Escribano, A., Gómez-Lázaro, E., Fortmann, J., Sørensen, P., & Martin-Martinez, S. (2018). 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Real-time monitoring system for shelf life estimation of fruit and vegetables

The control of the main environmental factors that influence the quality of perishable products is one of the main challenges of the food industry. Temperature is the main factor affecting quality, but other factors like relative humidity and gas concentrations (mainly C2H4, O2 and CO2) also play an important role in maintaining the postharvest quality of horticultural products. For this reason, monitoring such environmental factors is a key procedure to assure quality throughout shelf life and evaluate losses. Therefore, in order to estimate the quality losses that a perishable product can suffer during storage and transportation, a real-time monitoring system has been developed. This system can be used in all post-harvest steps thanks to its Wi-Fi wireless communication architecture. Several laboratory trials were conducted, using lettuce as a model, to determine quality-rating scales during shelf life under different storage temperature conditions. As a result, a multiple non-linear regression (MNLR) model is proposed relating the temperature and the maximum shelf life. This proposed model would allow to predict the days the commodities will reduce their theoretical shelf-life when an improper temperature during storage or in-transit occurs. The system, developed as a sensor-based tool, has been tested during several land transportation trips around Europe.The authors are grateful to Fruca Marketing S.L. for providing the lettuce used in this research, and to Transportes Directos del Segura SL and Transportes Mesa SL for the logistic support. We also are grateful to Miriam Montoya Gómez for the translation services

Tectonic Control on Sedimentary Dynamics in Intraplate Oceanic Settings: A Geomorphological Image of the Eastern Canary Basin and Insights on its Middle-Upper Miocene to Quaternary Volcano-Tectonic-Sedimentary Evolution

This paper integrates sedimentary, tectonic and volcanic geological processes inside a model of volcano-tectonic activity in oceanic intraplate domains related to rifted continental margins. The study case, the eastern Canary Basin (NE Atlantic), is one of the few places in the world where giant MDTs and Quaternary volcanic and hydrothermal edifices take place in intraplate domains. In this paper, we analyse how two structural systems (WNW-ESE and NNE-SSW) matching with the oceanic fabric control the location of volcanic systems, seafloor tectonic reliefs and subsequently the distribution of main sedimentary systems. Linear turbidite channels, debris flow lobes and the lateral continuity of structural and volcanic reliefs follow a WNW-ESE trend matching the tracks of the oceanic fracture zones. Furthermore, escarpments, anticline axes and volcanic ridges follow a NNE-SSW trend matching normal faults delimiting blocks of oceanic basement. The morpho-structural analysis of all the above geomorphological features shows evidence of a volcanic and tectonic activity from the middle–upper Miocene to the Lower–Middle Pleistocene spread over the whole of the eastern Canary Basin that reached the western Canary Islands. This reactivation changes the paradigm in the seamount province of Canary Islands reported inactive since Cretaceous. A tecto-sedimentary model is proposed for this period of time that can be applied in other intraplate domains of the world. A tectonic uplift in the study area with a thermal anomaly triggered volcanic and hydrothermal activity and the subsequent flank collapse and emplacement of mass transport deposits on the Western Canary Slope. Furthermore, this uplift reactivated the normal basement faults, both trending WNW-ESE and NNE-SSW, generating folds and faults that control the location of turbidite channels, escarpments, mass transport deposits and volcanic edifices.Versión del edito

Ansiedad entre cuidadores de pacientes con Enfermedad Pulmonar Obstructiva Crónica tras el alta hospitalaria

Objective: To identify the factors that influence changes in caregivers anxiety status three months after discharge for acute exacerbation of Chronic Obstructive Pulmonary Disease (COPD).Methodology: Longitudinal study. Participants included 87 caregivers of patients hospitalized for acute exacerbation of COPD. Anxiety was measured at the time of hospitalization and three months after discharge. We measured factors from four domains: context of care, caregiving demands, caregiver resources, and patient characteristics. We used multiple univariate and multivariate logistic regressions to determine changes in anxiety three months later. Univariate and multivariate multiple logistic regressions were used to determine changes in anxiety three months later.Results: A total of 57.5% of caregivers reported anxiety at the time of hospitalization. Of these, 44% had a remission of their anxiety three months after discharge. However, 22% of caregivers who had not experienced anxiety at the hospitalization became anxious at 3 months. The severity of COPD and not receiving help from another caregiver decreased the likelihood of remission of anxiety. Moderately high overload increases the likelihood of experiencing anxiety symptoms.Conclusions: The perception of anxious symptoms is dynamic. Caregivers are likely to recover from anxiety when they receive help from another caregiver and if the patient they are caring for does not have severe COPD.Objetivo: Identificar los factores que influyen en cambios en la ansiedad de los cuidadores tres meses después del alta hospitalaria por exacerbación aguda de la Enfermedad Pulmonar Obstructiva Crónica (EPOC).  Metodología: Estudio longitudinal. Participaron 87 cuidadores de pacientes hospitalizados por exacerbación aguda de EPOC. Se midió la ansiedad en el momento de la hospitalización y tres meses después del alta. Además, se midieron potenciales factores asociados a su cambio en cuatro dominios: Contexto del cuidado, demandas del cuidado, recursos y características del paciente. Utilizamos regresiones logísticas múltiples univariadas y multivariadas para determinar los cambios en la ansiedad tres meses después. Resultados: Presentaron ansiedad en el momento de la hospitalización el 57,5% de los cuidadores. De ellos, el 44% había remitido su ansiedad tres meses después del alta hospitalaria. Sin embargo, el 22% de los cuidadores quienes no habían presentado ansiedad en el momento de la hospitalización se mostraron ansiosos a los 3 meses. La gravedad de la EPOC y no recibir apoyo de otro cuidador disminuyó las probabilidades de remisión de la ansiedad. La sobrecarga moderadamente alta incrementa las probabilidades de presentar  nuevos síntomas de ansiedad. Conclusiones: La percepción de los síntomas de la ansiedad es dinámica. Los cuidadores pueden recuperarse si reciben ayuda de otro cuidador o si el paciente al que cuidan no está en un estado severo de EPOC

Morfometría de montículos submarinos del talud inferior del margen continental canario (O de las Islas Canarias): Análisis basado en un MDT

We present a morphometric analysis of 41 mounded edifices located on the seafloor to the west of Canary Islands, using a 150 m resolution DEM and very high-resolution seismic profiles. In order to carry out morphometric computation a set of variables (slope, size and shape) were calculated using ArcGIS Analyst tools. A mapping cluster has been generated using Grouping Analyst ArcGIS Statistics toolset where seven differents morphometric groups have been distinguished. Four main types of edifice shapes have been identified within the seven morphometric groups. The first type is a single giant dome elevation that can be considered as an outlier mound. The second type is the most frequent and can be considered as the standard type mound on the Canary continental slope due to its intermediate morphology. They show extrusive seismic characteristics in seismic profiles. The third type is morphologically derived from type 2, representing steeper and higher mounds related with extrusive processes whereas the fourth type represents smoother and flatter mounds related to faulting. This study shows that an elaborated geomorphometry resolves between types of extrusive edifices from those under tectonic conditionsVersión del edito

Acute and subchronic 90-days toxicity assessment of propyl-propane-thiosulfinate (PTS) in rats

The organosulfur compounds (OSC) extracted from Allium spp. exhibit antibacterial, antifungal, and antioxidant properties. The agri-food industry is taking advantage of these properties by using them as natural feed and food additives. In the present work, an acute and a subchronic 90-days toxicity studies have been conducted for the first time to assess the safety of the OSC propyl-propane-thiosulfinate (PTS). Both studies were carried out following the Organization for Economic Co-operation and Development test guidelines (425 and 408, respectively). The acute study provided a maximum tolerated dose (MTD) of 175 mg/kg and the subchronic study established the Non Observed Adverse Effect Level (NOAEL) ≥ 55 mg/kg body weight (b.w.)/day in both sexes. In addition, the subchronic study performed on rats exposed to 14, 28 and 55 mg/kg b.w./day PTS, revealed no changes in any of the hematological parameters measured as well as no differences in body weight and water/food consumption. However, biochemical parameters were altered in some groups, although they were not biologically significant (Ca2+ in female rats, and the thyroids hormones T3 and T4 in rat males). Furthermore, the histopathological assessment evidenced no abnormality on the gastrointestinal, respiratory, lymphoid, urinary, circulatory, nervous, musculoskeletal, and reproductive systems.Ministerio de Ciencia e Innovación RTC-2017-6199-2Junta de Andalucía AT 2017–5323 and P18-TP-214