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Design of reinforced concrete enclosures infilled with clay block masonry (Part 1)
Im Rahmen des europäischen Verbundprojekts INSYSME wurden von den deutschen Partnern die Systeme IMES und INODIS zur Verbesserung des seismischen Verhaltens von ausgefachten Stahlbetonrahmen entwickelt. Ziel beider Systeme ist es, Stahlbetonrahmen und Ausfachung zu entkoppeln, anstatt die Tragfähigkeit durch aufwendige und kostspielige zusätzliche Bewehrungseinlagen zu erhöhen. Erste Ergebnisse des Systems IMES für Belastungen in und senkrecht zu der Wandebene werden vorgestellt.Within the scope of the joint European project INSYSME, the German partners developed two systems - IMES and INODIS - for improving the seismic behaviour of masonry infilled reinforced concrete frames. The purpose of both systems is to decouple frame and infill instead of working to improve their load-bearing capacity by means of elaborate, expensive, supplementary reinforcing elements. Initial findings for the IMES system with regard to the loads acting in-plane and perpendicular to the wall plane (out-of-plane) are presented
Seismic performance of multi-component systems in special risk industrial facilities
Past earthquakes demonstrated the high vulnerability of industrial facilities equipped with complex process technologies leading to serious damage of the process equipment and multiple and simultaneous release of hazardous substances in industrial facilities. Nevertheless, the design of industrial plants is inadequately described in recent codes and guidelines, as they do not consider the dynamic interaction between the structure and the installations and thus the effect of seismic response of the installations on the response of the structure and vice versa. The current code-based approach for the seismic design of industrial facilities is considered not enough for ensure proper safety conditions against exceptional event entailing loss of content and related consequences. Accordingly, SPIF project (Seismic Performance of Multi- Component Systems in Special Risk Industrial Facilities) was proposed within the framework of the European H2020 - SERA funding scheme (Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe). The objective of the SPIF project is the investigation of the seismic behavior of a representative industrial structure equipped with complex process technology by means of shaking table tests. The test structure is a three-story moment resisting steel frame with vertical and horizontal vessels and cabinets, arranged on the three levels and connected by pipes. The dynamic behavior of the test structure and installations is investigated with and without base isolation. Furthermore, both firmly anchored and isolated components are taken into account to compare their dynamic behavior and interactions with each other. Artificial and synthetic ground motions are applied to study the seismic response at different PGA levels. After each test, dynamic identification measurements are carried out to characterize the system condition. The contribution presents the numerical simulations to calibrate the tests on the prototype, the experimental setup of the investigated structure and installations, selected measurement data and finally describes preliminary experimental results
Novel analytical tools reveal that local synchronization of cilia coincides with tissue-scale metachronal waves in zebrafish multiciliated epithelia
Motile cilia are hair-like cell extensions that beat periodically to generate fluid flow along various epithelial tissues within the body. In dense multiciliated carpets, cilia were shown to exhibit a remarkable coordination of their beat in the form of traveling metachronal waves, a phenomenon which supposedly enhances fluid transport. Yet, how cilia coordinate their regular beat in multiciliated epithelia to move fluids remains insufficiently understood, particularly due to lack of rigorous quantification. We combine experiments, novel analysis tools, and theory to address this knowledge gap. To investigate collective dynamics of cilia, we studied zebrafish multiciliated epithelia in the nose and the brain. We focused mainly on the zebrafish nose, due to its conserved properties with other ciliated tissues and its superior accessibility for non-invasive imaging. We revealed that cilia are synchronized only locally and that the size of local synchronization domains increases with the viscosity of the surrounding medium. Even though synchronization is local only, we observed global patterns of traveling metachronal waves across the zebrafish multiciliated epithelium. Intriguingly, these global wave direction patterns are conserved across individual fish, but different for left and right noses, unveiling a chiral asymmetry of metachronal coordination. To understand the implications of synchronization for fluid pumping, we used a computational model of a regular array of cilia. We found that local metachronal synchronization prevents steric collisions, i.e., cilia colliding with each other, and improves fluid pumping in dense cilia carpets, but hardly affects the direction of fluid flow. In conclusion, we show that local synchronization together with tissue-scale cilia alignment coincide and generate metachronal wave patterns in multiciliated epithelia, which enhance their physiological function of fluid pumping
A human factors-aware assistance system in manufacturing based on gamification and hardware modularisation
Assistance systems have been widely adopted in the manufacturing sector to facilitate various processes and tasks in production environments. However, existing systems are mostly equipped with rigid functional logic and do not provide individual user experiences or adapt to their capabilities. This work integrates human factors in assistance systems by adjusting the hardware and instruction presented to the workers’ cognitive and physical demands. A modular system architecture is designed accordingly, which allows a flexible component exchange according to the user and the work task. Gamification, the use of game elements in non-gaming contexts, has been further adopted in this work to provide level-based instructions and personalised feedback. The developed framework is validated by applying it to a manual workstation for industrial assembly routines
Bambus als Baumaterial : eine nachhaltige Alternative zu herkömmlichen Rohstoffen?
"Das Editorial greift die Thematik der aktuellen Klimakrise auf und beleuchtet diese im Bereich des nachhaltigen Bauens. Denn durch das stetige Wachstum der menschlichen Bevölkerung in Kombination mit dem Anstieg des Pro-Kopf-Verbrauchs werden globale Ressourcen immer stärker belastet. Ziel der Arbeit ist es, die aktuelle Situation des Klimawandels aus einer Perspektive zu betrachten, der sich die meisten nicht bewusst sind. Denn besonders das Bauwesen trägt einen erheblichen Anteil zum Klimawandel bei. In der Publikation werden Texte zum Thema Klimawandel und nachhaltiges Bauen behandelt sowie fotografische Anwendungsbeispiele im Bereich der Bambus-Architektur gezeigt. Das Projekt präsentiert Lösungsansätze, wie herkömmliche Rohstoffe durch verarbeiteten Bambus ergänzt bzw. ersetzt werden können. Dadurch kann ein entscheidender Beitrag zur Bekämpfung des Klimawandels geleistet werden. Bambus bietet dahingehend viele Möglichkeiten. Bei richtiger Verarbeitung vereint er viele der geforderten Ansprüche nachhaltigen Bauens. Der Rohstoff ist stark und flexibel zugleich. Er bindet Kohlenstoff, reinigt kontaminierte Böden, beugt Erosionen vor und weist eine nahezu negative CO2-Bilanz auf. Wie kann es gelingen, diesen Rohstoff in westlichen Ländern als Baumaterial zu integrieren?
ADIE : Keramische Fassaden- und Wandverkleidung - Funktion und Wirkung von Schönheit im Design
„ADIE“ ist eine Produktfamilie von Keramikplatten und Fliesen mit dreidimensionaler Oberfläche, welche durch Form und Farbe Schönheit zum Ausdruck bringen. Sie sind sowohl im Kontext der Architektur als Fassadenverkleidung anwendbar als auch im Innenbereich als Wandverkleidung. Die Fähigkeit von Schönheit, unsere Umgebung zu transformieren, nimmt eine leitende Rolle in dieser Arbeit ein. Als Inspirationsquelle für die Entwürfe dienten Dinge, die dem allgemeinen Schönheitsempfinden entsprechen: Wasser, Blüten, der Himmel und andere Naturphänomene. Diese wurden abstrahiert, in Reliefs übersetzt und in drei unterschiedliche Module weiterentwickelt. Sie sind konzeptionell frei skalierbar und wurden in Kleinserie im Gussverfahren prototypisiert. Mit „ADIE“ sollte auf die Funktion von Schönheit im Design Bezug genommen werden und etwas entstehen, das einfach „nur“ schön ist
X Plore: human hybrid submarine
Das „X Plore“ ist ein human hybrid angetriebenes Tauchboot, welches sowohl für den touristischen als auch privaten Gebrauch konzipiert ist. Das immersive Design des „X Plore" sorgt für ein eindrucksvolles Taucherlebnis. Das Konzept soll die Menschen über die aktuelle Not der Meere und ihrer Lebewesen aufklären und ihnen gleichzeitig die Möglichkeit geben, der Unterwasserwelt näher zukommen. Zudem soll es diese erhalten und ihre Bewohner:innen schützen. Des Weiteren thematisiert die Arbeit zukunftsorientierte Antriebs- und Batterietechniken und setzt sich mit der sinnvollen Integrierung dieser auseinander
Framework to provide a simulative comparison of different energy market designs
Useful market simulations are key to the evaluation of diferent market designs existing of multiple market mechanisms or rules. Yet a simulation framework which has a comparison of diferent market mechanisms in mind was not found. The need to create an objective view on different sets of market rules while investigating meaningful agent strategies concludes that such a simulation framework is needed to advance the research on this subject. An overview of diferent existing market simulation models is given which also shows the research gap and the missing capabilities of those systems. Finally, a methodology is outlined how a novel market simulation which can answer the research questions can be developed
System concept and realization of a scalable neurocomputing architecture
This paper describes the realization of a novel neurocomputer which is based on the concepts of a coprocessor. In contrast to existing neurocomputers the main interest was the realization of a scalable, flexible system, which is capable of computing neural networks of arbitrary topology and scale, with full independence of special hardware from the software's point of view. On the other hand, computational power should be added, whenever needed and flexibly adapted to the requirements of the application. Hardware independence is achieved by a run time system which is capable of using all available computing power, including multiple host CPUs and an arbitrary number of neural coprocessors autonomously. The realization of arbitrary neural topologies is provided through the implementation of the elementary operations which can be found in most neural topologies
What is the best spectroscopic method for simultaneous analysis of organic acids and (poly)saccharides in biological matrices: Example of Aloe vera extracts?
Several species of (poly)saccharides and organic acids can be found often simultaneously in various biological matrices, e.g., fruits, plant materials, and biological fluids. The analysis of such matrices sometimes represents a challenging task. Using Aloe vera (A. vera) plant materials as an example, the performance of several spectro-scopic methods (80 MHz benchtop NMR, NIR, ATR-FTIR and UV–vis) for the simultaneous analysis of quality parameters of this plant material was compared. The determined parameters include (poly)saccharides such as aloverose, fructose and glucose as well as organic acids (malic, lactic, citric, isocitric, acetic, fumaric, benzoic and sorbic acids). 500 MHz NMR and high-performance liquid chromatography (HPLC) were used as the reference methods.
UV–vis data can be used only for identification of added preservatives (benzoic and sorbic acids) and drying agent (maltodextrin) and semiquantitative analysis of malic acid. NIR and MIR spectroscopies combined with multivariate regression can deliver more informative overview of A. vera extracts being able to additionally quantify glucose, aloverose, citric, isocitric, malic, lactic acids and fructose. Low-field NMR measurements can be used for the quantification of aloverose, glucose, malic, lactic, acetic, and benzoic acids. The benchtop NMR method was successfully validated in terms of robustness, stability, precision, reproducibility and limit of detection (LOD) and quantification (LOQ), respectively. All spectroscopic techniques are useful for the screening of (poly)saccharides and organic acids in plant extracts and should be applied according to its availability as well as information and confidence required for the specific analytical goal. Benchtop NMR spectroscopy seems to be the most feasible solution for quality control of A. vera products