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Floods including sediment transport are a significant threat to communities in Austria. With climate change impacting the Alps, it is crucial to enhance and reassess protective measures. Predictions for the future of the Alpine climate indicate that there will be more winter precipitation and stronger, convective rain in the summer, even if the temperature goals set by the Paris Agreement are met.However, analyzing the impact of increased extreme precipitation on flood events in small Alpine catchments remains a challenge, and knowledge of the subsequent impacts on sediment transport is still insufficient. The catchment area of the Schöttlbach and thus the town of Oberwölz (Murtal, Styria) were affected by extreme flood events with extreme sediment transport in both 2011 and 2017, which caused heavy damage. The region was therefore selected to work with local stakeholders (especially the Austrian Torrent and Avalanche Control authorities) to improve the process understanding of flood events and sediment transport in a torrent catchment area and to draw possible climate change scenarios for the future.It was the aim of the project „RunSed-CC“ (i) to estimate future runoff and sediment transport in an Alpine catchment using the latest climate projections (ÖKS15), (ii) to consider them in the light of the associated model uncertainties, and (iii) the potential for extrapolating the results to other Alpine catchments to test.One focus of the project was the collection of natural data using a wide variety of measurements in the catchment area of an alpine torrent.The project RunSed-CC developed further a model that connects rainfall and runoff to sediment transport. The hydrological model WaSiM was used, in combination with data on the evolution of sediment source areas, to drive the 2D numerical models Telemac-2D (hydrodynamics) & Sisyphe (sediment transport). The main focus of the project was to understand the potential impacts of future climate change on the hydrologic regime, changes in sediment dynamics and sediment yield, and associated uncertainties in the model.This article is intended to provide a brief outline of the results of the extensive project, with a focus on the final findings of the sediment balances at the outlet of the catchment area.

ZusammenfassungBeckenartige Fischaufstiegshilfen lassen sich auf Basis ihrer Charakteristik grundsätzlich in Schlitzpässe mit einheitlicher Sohlneigung und Beckenpässe, welche durch Anrampung im Übergang errichtet werden, unterteilen. Dabei gelten der Vertical-Slot-Schlitzpass und der naturnahe Beckenpass als beprobte Bautypen. Im Zuge der Umsetzung der Wasserrahmenrichtlinie wurden zahlreiche Beckenpässe, entgegen der naturnahen Variante, welche sich durch die Gestaltung der Übergänge mit Wasserbausteinen auszeichnet, mit technischen, betonierten Übergängen errichtet. Da technische Beckenpässe baulich-wirtschaftliche Vorteile gegenüber der naturnahen Variante bieten sowie mit einer exakten Bemessungs- bzw. Errichtungsmöglichkeit gegenüber dem naturnahen Beckenpass punkten und daher vermehrt zur Ausführung kommen, widmet sich der vorliegende Beitrag der hydraulischen und biotischen Analyse dieser Variante.

We explain how to optimize the image analysis of mixed clusters of red and green droplets in solvents with various degrees of sharpness, brightness, contrast and density. The circular Hough Transform is highly efficient for separated circles with reasonable background contrast, but not for large amounts of partially overlapping shapes, some of them blurred, as in the images of our dense droplet suspensions. We explain why standard approaches for image improvement fail and present a “shootout” approach, where already detected circles are masked, so that the removal of sharp outlines improves the relative optical quality of the remaining droplets. Nevertheless, for intrinsic reasons, there are limits to the accuracy of data which can be obtained on very dense clusters.

Within the scope of the European Horizon 2020 project ACDC – Artificial Cells with Distributed Cores to Decipher Protein Function, we aim at the development of a chemical compiler governing the three-dimensional arrangement of droplets, which are filled with various chemicals. Neighboring droplets form bilayers containing pores through which chemicals can move from one droplet to its neighbors. When achieving a desired three-dimensional configuration of droplets, we can thus enable gradual biochemical reaction schemes for various purposes, e.g., for the production of some desired macromolecules for pharmaceutical purposes. In this paper, we focus on geometric restrictions to possible arrangements of droplets. We present analytic results for the buttercup problem and a heuristic optimization method for the kissing number problem, which we then apply to find (quasi) optimum values for a bidisperse kissing number problem, in which the center sphere exhibits a larger radius.

We aim at planning and creating specific agglomerations of droplets to study synergic communication using these as programmable units. In this paper, we give an overview of preliminary obstacles for the various research issues, namely of how to create droplets, how to set up droplet agglomerations using DNA technology, how to prepare them for confocal microscopy, how to make a computer see droplets on photos, how to analyze networks of droplets, how to perform simulations mimicking experiments, and how to plan specific agglomerations of droplets.

ZusammenfassungIn diesem Beitrag wird auf die hydrodynamische Modellierung mit frei verfügbaren Softwarepaketen eingegangen. Besonderes Augenmerk liegt hierbei auf den Rollen von Personen in der Entwicklung und Anwendung sowie auf deren Stellenwert im Laufe der Zeit. Charakteristiken von frei verfügbarer und kommerzieller Software werden vorgestellt und die jeweiligen Vor- und Nachteile diskutiert. Mittels vier Anwendungsbeispielen werden die Möglichkeiten der Adaptierung von frei verfügbarer Software für neue Entwicklungen bzw. für die Lösung von projektspezifischen Aufgabenstellungen vorgestellt: (i) Berücksichtigung von hydraulischen Verlusten in einem 2D tiefengemittelten Modell, (ii) Implementierung von internen Randbedingungen, (iii) Serielle Kopplung von Modellen, (iv) Auswertung von Zeitreihen mittels Python. Die vorgestellten Überlegungen werden zum Schluss diskutiert und zusammengefasst.

Exponential growth of computational power in the past decade on one hand and the success of numerical models in studying hydro-environmental flows on the other hand lead to an increasing usage of this technique in hydraulic engineering problems. In particular, three-dimensional numerical models are becoming the industry standard, especially in problems where capturing three-dimensional flow characteristics are important. Additionally, with availability of open-source computational fluid dynamic (CFD) codes, this type of modelling is more accessible. Among these codes, OpenFOAM (Open Source Field Operation and Manipulation) is a state-of-the-art CFD code with an extensive range of features for engineering and scientific applications. In this paper, selected studies are presented which the authors carried out using OpenFOAM. These studies include a wide range of applications from implementation of the new algorithms to modelling a practical application in hydraulic engineering.

In this publication, the model by Ramsey, Pierce, and Bowman for finding the hierarchical order of the various sectors of an economy, conceiving each of them as users or suppliers for other sectors of the economy, is investigated. Computational results for a benchmark instance are provided.

We simulate the movement and agglomeration of oil droplets in water under constraints, like confinement, using a simplified stochastic-hydrodynamic model. In the analysis of the network created by the droplets in the agglomeration, we focus on the paths between pairs of droplets and compare the computational results for various system sizes.

Unlined pressure tunnels in sound rock, combined with pressurized sand traps at the downstream end, allow for low-cost construction of hydropower tunnel systems. This design concept is utilized in hydropower plants across the world. Currently, many such power plants are being upgraded with higher installed capacity, which may result in challenges with the sand trap efficiency. A physical scale model test, accompanied by 3D CFD simulations of a case study pressurized sand trap, has been studied for economic retrofitting. The geometric model scale is 1:36.67 while the velocity scale and sediment scale are 1:1 (same average flow velocity and sediment size in model and prototype). This is currently an uncommon scaling approach but with several advantages, as presented in this paper. Various options for retrofitting were investigated. A combined structure of ramp and ribs was found to significantly improve the sediment trap efficiency. The main novelties from this work are the proposed design of the combined ramp and rib structure. Secondary results include an efficient setup for physical scale models of pressurized sand traps and a methodology that combines the benefits of 3D CFD simulations with physical scale models testing for sand trap engineering and design.

Resumo: No capítulo 5 do Livro III De anima (430a10-19) Aristóteles distingue entre o νοῦς ποιητικός (nous poietikós), chamado pelos Latinos intellectus agens (intelecto agente), e νοῦς παθητικός (nous pathetikós), chamado pelos Latinos intellectus passivus, ou seja, intellectus possibilis (intelecto possível), termos técnicos e filosóficos mais comuns. O capítulo 5 é de grande importância não só para a filosofia antiga e para os comentadores das obras de Aristóteles, como os comentários de Teofrasto, de Alexander de Afrodisias, de Simplício e Themístius entre outros, mas também para a filosofia do mundo árabe e da Europa latina. Sabe-se que Aristóteles não escreveu um tratado próprio sobre o intelecto, embora possam ser encontradas várias observações acerca do intelecto em suas obras. Os tratados do Intelecto começam com Al-Kindi, Al-Farabi, Avicena e sobretudo Averróis, e se refletem, num sentido crítico e afirmativo, (nos debates) dos tratados latinos, por exemplo, nos tratados de Alberto Magno, de Tomás de Aquino, de Sigério de Brabant entre outros. Este artigo apresenta observações preliminares e preparatórias ao projeto de traduções bilíngue (Latim-Português) dos tratados medievais sobre o intelecto ‘Teorias do Intelecto na Idade Média’ que está em desenvovlimento no Centro Internacional de Estudos Medievais da UFU. Palavras-chaves: Unidade do intelecto; Imaginação; Intencionalidade; Luz intelectual e cognição. Theories of the Intellect in the Latin Middle Ages. De anima III, cap. 5 of Aristotle and his Medieval Tradition Abstract: In the chapter 5 of the III. Book of De anima (430a10-19) Aristotle distinguishes between the νοῦς ποιητικός (nous poietikós) called by the Latins intellectus agens (agent intellect) and the νοῦς παθητικός (nous pathetikós) called by the Latins intellectus passivus, or intellectus possibilis (possible intellect), most common technical and philosophical terms. The chapter 5 is of great importance not only to ancient philosophy and to the commentators of Aristotle’s works such as the commentaries of Theophrastus, Alexander of Aphrodisias, of Simplicius, and Themistius among others, but also to the philosophy of the Arabic World and the Latin Europe. One knows well that Aristotle does not have written a proper treatise on intellect; although there are several observations about the intellect in his works. Separate treatises begin with Al-Kindi, Al-Farabi, Avicenna, and especially Averroes, which Latin treatises as of Albert the Great, Thomas Aquinas, Siger of Brabant among others reflect in a critical as well as an affirmative sense. This article can be read as preliminary and preparatory observations to a bilingual (Latin-Portuguese) translation project of treatises corresponding to ‘Theories of Intellect in the Middle Ages’ which is ongoing at the International Center for Medieval Studies at UFU. Key-words: Unity of the Intellect; Imagination; Intentionality; Intellectual Light; and Cognition. Theorien des Intellekts im Lateinischen Mittelalter. De anima III, 5 des Aristoteles und seine mittelalterliche Tradition Zusammenfassung: Im 5. Kapitel des III. Buchs von De anima (430a10-19) unterscheidet Aristoteles zwischen dem νοῦς ποιητικός (nous poietikós), von den Lateinern intellectus agens (tätiger Intellekt) genannt und dem νοῦς παθητικός (nous pathetikós), von den Lateinern intellectus passivus oder auch intellectus possibilis (möglicher Intellekt) genannt, gemeinhin bekannte technische und philosophische Begriffe. Dieses 5. Kapitel ist von grösster Bedeutung nicht nur für die antike Philosophie und die Kommentatoren der Werke des Aristoteles wie die Kommentare des Theophrastus, des Alexander von Aphrodisias, Simplicius und Themistius unter anderen, sondern auch für die Philosophie der arabischen Welt und des lateinischen Europas. Bekanntlich hat Aristoteles keinen eigenen Traktat über den Intellekt geschrieben, obgleich sich viele Beobachtungen zum Intellekt in seinem Werk antreffen. Selbständige Traktate über den Intellekt beginnen mit Al-Kindi, Al-Farabi, Avicenna und besonders Averroes, die sich in den lateinischen Traktaten, z.B. des Albertus Magnus, Thomas von Aquin, Siger von Brabant und anderen zustimmend wie kritisch widerspiegeln. Dieser Artikel kann als vorläufige und vorbereitende Bemerkungen zu einem zweisprachigen (lateinisch-portugiesischen) Übersetzungsprojekt von Texten gelesen werden, welche „Theorien des Intellekts im Lateinischen Mittelalter“ betreffen. Dieses Projekt ist am Internationalen Zentrum für Mittelalterstudien der UFU in Arbeit genommen worden. Schlüsselwörter: Verstand; Vernunft; Intentionalität; Anschauung und Erkenntnis. Data de registro: 12/03/2020 Data de aceite: 21/10/2020

Resumo O presente estudo aborda a articulação entre ciência natural e cosmologia em Tomás de Aquino. Para tanto, são investigadas as concepções da noção de cosmo, mediante a questão: o cosmo (mundo ou universo) pode ser o assunto central da ciência natural em Tomás? No intuito de refletir sobre essa questão, são apresentadas três concepções de cosmo. A primeira é a concepção da metafísica, na qual o cosmo é uma hierarquia de entes. A segunda, por sua vez, é a concepção da cosmografia segundo a qual o cosmo é a relação de esferas intercaladas. A terceira, por fim, é a concepção da cosmologia que entende o cosmo como o conjunto dos corpos simples em perene locomoção natural. Abstract The present study aims to articulate natural science and cosmology in Thomas Aquinas. Accordingly, I want to investigate the conceptions of cosmos by the following question: can the cosmos (world or universe) be the central topic of natural science in Aquinas? I present three conceptions of cosmos in order to reflect upon this question. The first is the metaphysical one in which the cosmos is a hierarchy of entities. The second is related to cosmography according to which the cosmos is a relation of intercalated spheres. The third, finally, is the cosmological conception that understands the cosmos as the set of simple bodies in perennial natural locomotion.