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Abstract. The concept of wake steering on wind farms for power maximization has gained significant popularity over the last decade. Recent field trials described in the literature not only demonstrate the real potential of wake steering on commercial wind farms but also show that wake steering does not yet consistently lead to an increase in energy production for all inflow conditions. Moreover, a recent survey among experts shows that validation of the concept currently remains the largest barrier to adoption. In response, this article presents the results of a field experiment investigating wake steering in three-turbine arrays at an onshore wind farm in Italy. This experiment was performed as part of the European CL-Windcon project. While important, this experiment excludes an analysis of the structural loads and focuses solely on the effects of wake steering on power production. The measurements show increases in power production of up to 35 % for two-turbine interactions and up to 16 % for three-turbine interactions. However, losses in power production are seen for various regions of wind directions too. In addition to the gains achieved through wake steering at downstream turbines, more interesting to note is that a significant share in gains is from the upstream turbines, showing an increased power production of the yawed turbine itself compared to baseline operation for some wind directions. Furthermore, the surrogate model, while capturing the general trends of wake interaction, lacks the details necessary to accurately represent the measurements. This article supports the notion that further research is necessary, notably on the topics of wind farm modeling and experiment design, before wake steering will lead to consistent energy gains on commercial wind farms.

The current energy transition imposes a rapid implementation of energy storage systems with high energy density and eminent regeneration and cycling efficiency. Metal hydrides are potential candidates for generalized energy storage, when coupled with fuel cell units and/or batteries. An overview of ongoing research is reported and discussed in this review work on the light of application as hydrogen and heat storage matrices, as well as thin films for hydrogen optical sensors. These include a selection of single-metal hydrides, Ti-V(Fe) based intermetallics, multi-principal element alloys (high-entropy alloys), and a series of novel synthetically accessible metal borohydrides. Metal hydride materials can be as well of important usefulness for MH-based electrodes with high capacity (e.g. MgH2 ~ 2000 mAh g-1) and solid-state electrolytes displaying high ionic conductivity suitable, respectively, for Li-ion and Li/Mg battery technologies. To boost further research and development directions some characterization techniques dedicated to the study of M-H interactions, their equilibrium reactions, and additional quantification of hydrogen concentration in thin film and bulk hydrides are presented at the end of this manuscript.

We summarize and critically evaluate the available data on nuclear fusion cross sections important to energy generation in the Sun and other hydrogen-burning stars and to solar neutrino production. Recommended values and uncertainties are provided for key cross sections, and a recommended spectrum is given for 8B solar neutrinos. We also discuss opportunities for further increasing the precision of key rates, including new facilities, new experimental techniques, and improvements in theory. This review, which summarizes the conclusions of a workshop held at the Institute for Nuclear Theory, Seattle, in January 2009, is intended as a 10-year update and supplement to Reviews of Modern Physics 70 (1998) 1265. 54 pages, 20 figures, version to be published in Reviews of Modern Physics; various typos corrected and several updates made

AbstractConversion of semi-natural habitats, such as field margins, fallows, hedgerows, grassland, woodlots and forests, to agricultural land could increase agricultural production and help meet rising global food demand. Yet, the extent to which such habitat loss would impact biodiversity and wild species is unknown. Here we survey species richness for four taxa (vascular plants, earthworms, spiders, wild bees) and agricultural yield across a range of arable, grassland, mixed, horticulture, permanent crop, for organic and non-organic agricultural land on 169 farms across 10 European regions. We find that semi-natural habitats currently constitute 23% of land area with 49% of species unique to these habitats. We estimate that conversion of semi-natural land that achieves a 10% increase in agricultural production will have the greatest impact on biodiversity in arable systems and the least impact in grassland systems, with organic practices having better species retention than non-organic practices. Our findings will help inform sustainable agricultural development.

Impacts in the form of innovation and commercialization are essential components of publicly funded research projects. PHUSICOS ("According to nature" in Greek), an EU Horizon 2020 program (H2020) Innovation Action project, aims to demonstrate the use of nature-based solutions (NBS) to mitigate hydrometeorological hazards in rural and mountainous areas. The work program is built around key innovation actions, and each Work Package (WP) leader is specifically responsible for nurturing innovation processes, maintaining market focus, and ensuring relevance for the intended recipients of the project results. Key success criteria for PHUSICOS include up-scaling and mainstream implementation of NBS to achieve broader market access. An innovation strategy and supporting tools for implementing this within PHUSICOS has been developed and key concepts forming the basis for this strategy are presented in this research note.

La physique ouverte et cachée des saveurs lourdes dans les collisions nucléaires à haute énergie entre dans une nouvelle étape passionnante vers une compréhension plus claire des nouveaux résultats expérimentaux avec la possibilité de les lier directement à l'avancement de la chromodynamique quantique en treillis (QCD). Des résultats récents d'expériences et de développements théoriques concernant la dynamique des saveurs lourdes ouvertes et cachées ont été débattus lors de l'atelier de Lorentz Tomography of the Quark-Gluon Plasma with Heavy Quarks, qui s'est tenu en octobre 2016 à Leiden, aux Pays-Bas. Dans cette contribution, nous résumons les compréhensions communes identifiées et les stratégies développées pour les cinq prochaines années, qui visent à acquérir une connaissance approfondie des propriétés dynamiques du plasma quark-gluon. La física de sabor intenso abierta y oculta en colisiones nucleares de alta energía está entrando en una nueva y emocionante etapa para alcanzar una comprensión más clara de los nuevos resultados experimentales con la posibilidad de vincularlos directamente con el avance en la cromodinámica cuántica reticular (QCD). Los resultados recientes de experimentos y desarrollos teóricos sobre dinámicas abiertas y ocultas de sabor intenso se han debatido en el Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, que se celebró en octubre de 2016 en Leiden, Países Bajos. En esta contribución, resumimos los entendimientos comunes identificados y las estrategias desarrolladas para los próximos cinco años, que tienen como objetivo lograr un conocimiento profundo de las propiedades dinámicas del plasma de quarks y gluones. Open and hidden heavy-flavor physics in high-energy nuclear collisions are entering a new and exciting stage towards reaching a clearer understanding of the new experimental results with the possibility to link them directly to the advancement in lattice Quantum Chromo-Dynamics (QCD). Recent results from experiments and theoretical developments regarding open and hidden heavy-flavor dynamics have been debated at the Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, which was held in October 2016 in Leiden, The Netherlands. In this contribution, we summarize identified common understandings and developed strategies for the upcoming five years, which aim at achieving a profound knowledge of the dynamical properties of the quark-gluon plasma. تدخل فيزياء النكهة الثقيلة المفتوحة والمخفية في التصادمات النووية عالية الطاقة مرحلة جديدة ومثيرة نحو الوصول إلى فهم أوضح للنتائج التجريبية الجديدة مع إمكانية ربطها مباشرة بالتقدم في الديناميكيات الكمومية الشبكية (QCD). تمت مناقشة النتائج الأخيرة من التجارب والتطورات النظرية المتعلقة بديناميكيات النكهة الثقيلة المفتوحة والمخفية في ورشة لورنتز للتصوير المقطعي لبلازما كوارك- غلوون مع الكواركات الثقيلة، والتي عقدت في أكتوبر 2016 في ليدن، هولندا. في هذه المساهمة، نلخص التفاهمات المشتركة المحددة والاستراتيجيات المطورة للسنوات الخمس القادمة، والتي تهدف إلى تحقيق معرفة عميقة بالخصائص الديناميكية لبلازما كوارك- غلوون.