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Simulation models enable designers and operators to test different settings of the real systems while avoiding the large costs associated with experimental or practical systems. However, creating models that resemble the real physical system with acceptable accuracy and computational time remains a challenge for developers of such tools. With this motivation, a new simulation tool, the Virtual Solar Field (VSF), has been developed for line-focus power plants with single-phase heat transfer fluid (HTF) to assist in plant control during transient processes. VSF is a whole-field model based on an efficient coupling of hydraulic and thermal solvers that take into account the flow distribution in the parallel loops, as well as the transient conditions in the field. In this paper, some validation cases for VSF using data from Andasol-3 power plant are shown. Five test cases are examined, which include normal operation, start-up and evening operation during clear-sky and strong transients. The results show very good agreement with the real plant and some discrepancies are discussed and studied. The main sources of discrepancies are associated with difficulties in modelling all fine details of reality using the current technologies in some commercial power plants. For example, small cloud passage are not detected by the few weather stations in the power plant, as well as knowing the exact loop valve settings is not possible in Andasol-3. In addition, an overview of the potential applications of VSF are mentioned and briefly discussed. VSF offers a suitable platform for testing novel control strategies and assessing the performance of the solar fields.

Due to their thermal storage capability, concentrated solar power (CSP) plants have flexibility on electricity dispatch, being able to participate in balancing power markets. The development of an optimum electricity delivery schedule should be fast to react to updated forecast and the dynamic electricity markets, apart from considering best operational practices, as it brings significant cost reductions and improvement in plant performance. Therefore, dispatch optimization tools should combine financial and operational optimization with acceptable computational time. In this context, an innovative dispatch optimization algorithm used to derive a CSP plant operation schedule is presented. FRED is a heuristic rule-based algorithm used to optimize financial income while considering plant best operational practices. Simulations performed with a CSP plant tower model following FRED optimization strategy show the possibility of improved financial results with fast dispatch planning, ensuring the importance of this technology in the pathway to a highly renewable energy mix.

Las actividades relacionadas con la obtención de energía en las que las condiciones meteorológicas tengan un impacto crítico pueden beneficiarse de importantes mejoras en su rendimiento si las previsiones meteorológicas son acertadas. Con el surgimiento de la predicción probabilista este beneficio puede ser aún mayor pues, como se describe en otras partes de este libro y más adelante en este mismo capítulo, pueden tomarse mejores decisiones si se conocen las probabilidades asociadas a la superación de distintos umbrales de ocurrencia de eventos meteorológicos. Utilizando el lenguaje económico, usar predicciones probabilistas tiene un valor relativo mayor, si se saben utilizar y serán, por tanto, más rentables. Nuestro futuro sólo puede encontrarse en la energía sostenible, como es el caso de la solar o la eólica.

Einleitung: Verletzungen des Metakarpophalangealgelenkes gehen häufig mit einer vollständigen oder partiellen Ruptur des ulnaren Kollateralbandes des Daumens einher. Dies ist mit einer Instabilität des betroffenen Gelenkes assoziiert. Das ulnare Kollateralband ist oft an der Ansatzstelle[for full text, please go to the a.m. URL], 127. Kongress der Deutschen Gesellschaft für Chirurgie

Einleitung: Die aggressive Fibromatose ist eine benigne Neoplasie, welche mit einer hohen Rezidivrate nach erfolgter Operation einhergeht. Ziel dieser Studie war die Untersuchung des krankheitsfreien Überlebens und des Gesamtüberlebens bei Patienten mit aggressiver Fibromatose. Material[for full text, please go to the a.m. URL], 127. Kongress der Deutschen Gesellschaft für Chirurgie

Einleitung: Die hypertrophe Narbenbildung ist bei Brandverletzten eine großes frunktionenelles ästhetisches Problem und von hohem sozioökonomisches Interesse. Ziel dieser prospektiven randomisierten Studie war die objektive Evaluation der Narbenentstehung. Material und Methoden: Die[for full text, please go to the a.m. URL], 127. Kongress der Deutschen Gesellschaft für Chirurgie