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The growing need for computational performance is resulting in an increase in the energy consumption of HPC systems, which is a major challenge to reach Exascale computing. To overcome this challenge, we developed a tuning plugin that targets applications that exhibit dynamically changing characteristics between iterations of the time loop as well as change in the control flow within the time loop itself. To analyze the inter-loop dynamism, we propose features to characterize the behaviour of loops for clustering via DBSCAN and spectral clustering. To save tuning time and costs, we implemented a random search strategy with a Gaussian probability distribution model to test a large number of system configurations in a single application run. The goal is to select the best configurations of the CPU and uncore frequencies for groups of similarly behaving loops, as well as individual instances of regions called within these loops based on their unique computational characteristics. During production runs, the configurations are dynamically switched for different code regions. The results of our experiments for two highly dynamic real-world applications highlight the effectiveness of our methodology in optimizing energy-efficiency.

Gasification is considered to be a promising way to use biomass with high efficiency in combined heatand power production, for the production of second generation biofuels and in the chemical industry.Especially allothermal fluidized bed steam gasification produces a medium calorific, nitrogen free gassuitable for a variety of downstream processes. In general the raw product gas has to be cleaned fromcondensable hydrocarbons (tar) and conditioned (e.g. adjustment of the H2/CO-ratio) before downstreamuse. The operating conditions of the gasification reactor have a large impact on the quality of the productgas. Hence first steps to a product gas low in tar content can be undertaken directly in the reactor. In thisstudy the capability of influencing the tar content and gas composition by changing temperature (750?840 C), steam to biomass (S/B) ratio (0.8?1.2) and pressure (0.1?0.25 MPa) in an allothermal bubblingfluidized bed steam gasifier is investigated. It is found that rising temperature reduces the total tar contentand affects especially heterocyclic and light aromatic compounds. At atmospheric pressure the naphthalenecontent increases slightly with increasing temperature in contrary to pressurized gasificationwhere naphthalene decreases significantly with increasing temperature. An increase in the S/B ratio leadsto a decreasing total tar content, this tar reduction according to a higher steam content is higher at highertemperatures. Increasing pressure leads to increasing total tar content mainly due to naphthalene, theeffect is most distinct for low S/B ratios.

Abstract The Organic Rankine Cycle can be applied to convert low temperature heat to electrical power using organic working fluids. Recently, a new generation of working fluids has been introduced with almost no Ozone Depletion Potential and significantly smaller Global Warming Potential, compared to currently used refrigerants. R1233zd-E is a promising low-GWP (global warming potential) alternative to R245fa, a widely used fluid in ORC (Organic Rankine Cycle) systems. This paper analyzes the applicability of the new fluid as drop-in replacement for R245fa in existing systems and compares system parameters such as cycle efficiency and power output. To this end, the influence of the process parameters mass-flow rate, condensation temperature and expander rotational speed is investigated experimentally for both fluids. The test rig used has an electrical heater as a heat source and a scroll compressor as an expander. As a conclusion, R1233zd-E can be used as a substitute for R245fa in existing ORC systems. In addition to the advantage of having a much smaller GWP, the use of R1233zd-E may lead to higher thermal efficiencies. Comparing the highest achieved thermal efficiency, R1233zd-E performs 6.92% better than R245fa. However, comparing the maximal gross power output, R245fa performs 12.17% better than R1233zd-E.

Application of aroma extract dilution analysis to Bartlett pears and the fermented mash produced thereof revealed 24 and 34 aroma-active compounds in the flavor dilution (FD) factor range between 8 and 8192. Twenty-eight compounds, which have not been described before in Bartlett pears or in fermented pear mash, were identified. While ethyl (E,Z)-2,4-decadienoate (pear-like, metallic odor impression), hexyl acetate (green, fruity), and acetic acid (vinegar-like) showed the highest concentrations in Bartlett pears, ethanol (ethanolic), acetic acid, 3-methyl-1-butanol (malty), 1-hexanol (grassy, marzipan-like), (S)-2- and 3-methylbutanoic acid (sweaty), and 2-phenylethanol (flowery, honey-like) were present at the highest amounts in the fermented mash. The key aroma compounds were quantitated in each pear brandy production step (pears, fermented mash, distillate, and aged distillate) by stable isotope dilution analysis showing a clear influence of each step on the overall aroma of the spirit and, consequently, revealing clearly changing concentrations (e.g., of ethyl (S)-2-methylbutanoate, (E)-β-damascenone, ethyl (E,Z)-2,4-decadienoate, and ethyl (E,E)-2,4-decadienoate) and different aroma perceptions during the manufacturing process. In addition, the concentrations of the so-called "pear esters" ethyl (E,Z)-2,4-decadienoate and ethyl (E,E)-2,4-decadienoate were determined in 6 different pear varieties (Abate Fetel, Anjou, Bartlett, Forelle, Kaiser Alexander, and Packham's Triumph) clearly demonstrating the aroma potential of the variety Bartlett, which is mostly used for brandy production due to the high amounts of both esters eliciting a typical pear-like odor impression.

Los nuevos sistemas inteligentes para ayudar a la transición energética y mejorar la sostenibilidad y la vida de las personas se pueden implementar a diferentes escalas, desde una casa hasta una región entera. Los campus universitarios son un tamaño intermedio interesante (lo suficientemente grande como para importar y lo suficientemente pequeño como para ser manejable) para la investigación, el desarrollo, las pruebas y la capacitación sobre la integración de la inteligencia en todos los niveles, lo que llevó a la aparición del concepto de "campus inteligente" en los últimos años. Este artículo de revisión propone un amplio análisis de la literatura científica sobre campus inteligentes de la última década (2010-2020). Las 182 publicaciones seleccionadas se distribuyen en siete categorías de inteligencia: edificio inteligente, entorno inteligente, movilidad inteligente, vida inteligente, personas inteligentes, gobierno inteligente y datos inteligentes. Las principales preguntas y desafíos abiertos con respecto a los campus inteligentes se presentan al final de la revisión y abordan la sostenibilidad y la transición energética, la aceptabilidad y la ética, los modelos de aprendizaje, las políticas de datos abiertos y la interoperabilidad. El presente trabajo se realizó en el marco de la Red de Energía de la Cumbre de Líderes Regionales (RLS-Energy) como parte de sus esfuerzos de investigación multilateral sobre regiones inteligentes. De nouveaux systèmes intelligents pour aider à la transition énergétique et améliorer la durabilité et la vie des gens peuvent être déployés à différentes échelles, allant d'une maison à une région entière. Les campus universitaires sont une taille intermédiaire intéressante (assez grande pour compter et assez petite pour être maniable) pour la recherche, le développement, les tests et la formation sur l'intégration de l'intelligence à tous les niveaux, ce qui a conduit à l'émergence du concept de « campus intelligent » au cours des dernières années. Cet article de synthèse propose une analyse approfondie de la littérature scientifique sur les campus intelligents de la dernière décennie (2010-2020). Les 182 publications sélectionnées sont réparties en sept catégories d'intelligence : smart building, smart environment, smart mobility, smart living, smart people, smart governance et smart data. Les principales questions et défis ouverts concernant les campus intelligents sont présentés à la fin de l'examen et traitent de la durabilité et de la transition énergétique, de l'acceptabilité et de l'éthique, des modèles d'apprentissage, des politiques de données ouvertes et de l'interopérabilité. Le présent travail a été réalisé dans le cadre du Réseau de l'énergie du Sommet des dirigeants régionaux (RLS-Energy) dans le cadre de ses efforts multilatéraux de recherche sur les régions intelligentes. Novel intelligent systems to assist the energy transition and improve sustainability and people's life can be deployed at different scales, ranging from a house to an entire region. University campuses are an interesting intermediate size (big enough to matter and small enough to be tractable) for research, development, test and training on the integration of smartness at all levels, which led to the emergence of the concept of "smart campus" over the last few years. This review article proposes an extensive analysis of the scientific literature on smart campuses from the last decade (2010-2020). The 182 selected publications are distributed into seven categories of smartness: smart building, smart environment, smart mobility, smart living, smart people, smart governance and smart data. The main open questions and challenges regarding smart campuses are presented at the end of the review and deal with sustainability and energy transition, acceptability and ethics, learning models, open data policies and interoperability. The present work was carried out within the framework of the Energy Network of the Regional Leaders Summit (RLS-Energy) as part of its multilateral research efforts on smart regions. يمكن نشر أنظمة ذكية جديدة للمساعدة في انتقال الطاقة وتحسين الاستدامة وحياة الناس على مستويات مختلفة، تتراوح من منزل إلى منطقة بأكملها. تعتبر الجامعات ذات حجم متوسط مثير للاهتمام (كبيرة بما يكفي لتكون مهمة وصغيرة بما يكفي لتكون قابلة للتتبع) للبحث والتطوير والاختبار والتدريب على تكامل الذكاء على جميع المستويات، مما أدى إلى ظهور مفهوم "الحرم الجامعي الذكي" على مدى السنوات القليلة الماضية. تقترح مقالة المراجعة هذه تحليلاً شاملاً للأدبيات العلمية حول الجامعات الذكية من العقد الماضي (2010-2020). يتم توزيع المنشورات الـ 182 المختارة على سبع فئات من الذكاء: البناء الذكي، والبيئة الذكية، والتنقل الذكي، والمعيشة الذكية، والأشخاص الأذكياء، والحوكمة الذكية، والبيانات الذكية. يتم تقديم الأسئلة والتحديات الرئيسية المفتوحة المتعلقة بالحرم الجامعي الذكي في نهاية المراجعة والتعامل مع الاستدامة وانتقال الطاقة والقبول والأخلاقيات ونماذج التعلم وسياسات البيانات المفتوحة وقابلية التشغيل البيني. تم تنفيذ العمل الحالي في إطار شبكة الطاقة التابعة لقمة القادة الإقليميين (RLS - Energy) كجزء من جهودها البحثية متعددة الأطراف حول المناطق الذكية.

Abstract We present a procedure for the efficient assessment of component importance and network reliability in power transmission grids subject to wind hazards. A stochastic wind load model is learned from windstorm data. Component fragility models are established by combining information on the design wind loads prescribed by the relevant structural codes and the observed failure rate in the network as a whole. Network performance is assessed by a DC power flow model, which accounts for cascading failures and potential islanding due to load redistribution after initial failure events caused by the windstorms. Besides evaluating the network reliability, selected importance measures are defined to rank single components according to their influence on the overall system reliability. We thereby distinguish component importance related to initial failures triggered by the windstorms and component importance related to potential subsequent cascading failures. The procedure is demonstrated by application to the Nordic Grid model of the electrical power transmission network in Denmark, Norway, Sweden, and Finland. We find that the procedure can provide an efficient basis for planning network improvements in terms of (1) strengthening vulnerable line segments against wind loads and (2) increasing line capacities to limit cascading failures.

This dataset fulfils the requirements for deliverable 4.1 of the EERAdata project and contains general data which models the building stock in three European cities - Andalusia, Copenhagen and Velenje. This dataset comprises local building data as well as research and scientific data. The dataset is still being built and will continue to be updated as more data is collected. A report describing this dataset in more detail has also been attached.

In this paper the design evolution from rolling piston compressor (RP) to revolving vane compressor (RV) and finally to cross-vane expander-compressor unit (CVEC) is presented and discussed. The details in the design philosophy which initiated this evolution will be presented and discussed.It is estimated that more than 90% of the room air-conditioners uses RP in its compressor. This is because of its advantages: it has the few parts, it is simple geometrically and it is reliable. However, it is with no weaknesses. RP's weaknesses lie in three parts:too many rubbing surfaces with high relative rubbing velocity with each other which give rise to high frictional losses;components (eccentric and roller) are not rotating at their centres and resulted in unnecessary inherent vibration;vane tip is constantly rubbing against the roller making it a weakest part in design.To overcome RP's weaknesses, RV is introduced. As compared to RP, RV has fewer rubbing surfaces, and the relative velocities among these surfaces are reduced Components in RV rotate at their own centres and there is no inherent vibration; the rubbing at the vane tip has been eliminated completely.However, like RP, RV also has a large rotor which occupied "useful" space and making the working chamber relatively small. To overcome this latter problem, CVEC is introduced. In this newly invented CVCE, not only parts are all concentric and rotate at their own centres, the unit also recovers expansion energy and hence significantly reduces energy required by the refrigeration systems. And, more importantly, all these are carried out not at the expense of the additional cost.In this paper, details on these three compressors are explained, compared and their respective uniqueness are shown and discussed.