Offenburg University of Applied Sciences
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Steps Toward Microstructure-Based Modeling of the Influence of Hydrogen on the Fatigue Behavior of Duplex Steels: Non-local Cyclic Polycrystal Plasticity
No full textWind energy from offshore wind turbines is an important part of the renewable energy revolution. Due to their good combination of strength and ductility and their corrosion resistance, duplex steels, such as 1.4462, are mainly used in these systems. Due to cathodic polarization, the material is exposed to the negative influence of hydrogen, which is known as hydrogen embrittlement. The influence of hydrogen on the material is affected by various aspects, such as the hydrogen activity in the environment and the mechanical loads. In addition, microstructural properties such as grain size, phase distribution, or different grain boundary types also influence hydrogen diffusion and mechanical behavior. Therefore, it is necessary to understand the influence of hydrogen on the fatigue behavior of the duplex steels. This requires modeling of both, diffusion and mechanical behavior, at the microstructural level. In this work, the mechanical behavior as the first step toward microstructure-based modeling of hydrogen-influenced duplex steels is addressed. Since hydrogen traps, such as dislocations, can have a significant influence on diffusion kinetics and hydrogen concentration in the material, a non-local gradient-based single-crystal plasticity model is used accounting for geometrically necessary dislocations. A computational model is developed for the analysis of the micromechanical behavior of the two-phase material and the evolution of the geometrically necessary dislocation densities
Maschinen wie wir und Menschen als Maschinen
No full textKaum etwas wird derzeit (mal wieder) so intensiv und kontrovers diskutiert wie Anwendungen der automatisierten Datenverarbeitung, die unter dem Label „Künstliche Intelligenz“ (KI) wahlweise alle Probleme der Menschheit lösen (soll) oder zu Untergang und Vernichtung der Spezies Mensch führen (würde). Die Extrempositionen von Heilsversprechen bis Weltuntergang (Doom) sind prominent besetzt, das Spektrum fantasievoll ausbuchstabiert. Ausgeblendet werden wirtschaftliche Interessen und Akteure. Dabei stellen sich bei diesem (mittlerweile dritten) KI-Hype die gleichen Fragen wie vor 50 oder 70 Jahren: Ist das Axiom der Kybernetik, die Gleichsetzung von Mensch und Maschine als steuerbares Regelsystem, tragfähig oder ein de-humanisierender Irrweg? Ist die Einflussnahme auf menschliches Verhalten durch automatisierte technische Systeme und algorithmisches Management zulässig oder führen digital transformierte Sozialsysteme notwendig in Kontrollgesellschaften? Was sind Alternativen
An Innovative, Fully 3D-Printed, Inherent Actuatorless, Concentric Gripper for Robotic Applications
No full textRecent advances in 3D printing technology have made it possible to produce functional objects and structures applying a variety of 3D printing processes and materials. This opens up new possibilities for gripping technology, enabling the flexible design of grippers for specific tasks. In this contribution we present an innovative, fully 3D-printed concentric gripper for robotic applications. A special feature of the gripper is that it does not require an inherent actuator, since the rotary axis on the robot flange is employed for this purpose. The gripper’s central component is a 3D-printed torque sensor, fabricated employing a five-axis 3D printing system. The sensor enables the measurement of forces occurring during the gripping process. The gripper concept is validated in a series of experiments in which different objects are gripped. The sensor signals during the gripping process are analysed and the functionality and reproducibility are demonstrated
SUDEM Foresight: Advanced Air Mobility Drone Operations Based on Future Advanced Communication Systems – as Crucial Elements of a System of Systems for Effective Disaster Management and Emergency Operations
No full textAdvanced Air Mobility (AAM), having drones (aerial robots) as a core, is becoming an integral additional part of Disaster Management (DM) systems in metropolitan regions, and of future smart urban development and systems. Unmanned Aircraft Systems (UAS) are able to transport efficiently high added value goods and to provide efficient monitoring during the disaster events and their development. This paper provides a foresight on the overall System of Systems (SoS) needed including the UAS application in the studied use cases, as well as the crucial integration of relevant advanced communication systems (ACS), for the safe and sustainable UAS operation. In the evolving AAM, ACS is a crucial enabler and core element of a functioning SoS -- for the purposes of UAS navigation and operations safety, DM data collection and processing. The emphasised SoS enables emergency goods deliveries and the complete and efficient deployment and operation of an entire DM system (meant for monitoring, search and rescue, and decision making support), where UASs are used as logistic tools, and simultaneously for the monitoring of the environment and the disaster events in the affected regions. AAM is being operated mainly in the third dimension (airspace), which enables us to be minimally dependent on any types of ground transport infrastructure. Due to this, its precise navigation and management as well as relevant data streams transfer are crucial for the operational efficiency and safety. This foresight study provides a comprehensive, SUDEM (EU), REGUAS (DE), 5G!Drones (EU), and ETHER (EU) projects' lessons learnt-based path for understanding and efficiently deploying the SUDEM SoS including AAM and ACS for the purpose of the described 2 combined use cases: (i) high-added value goods transport and (ii) live monitoring, and the necessary educational model
Die Risikolandschaft der KI-Transformation
No full textUnternehmen stehen in einem harten Wettbewerb und müssen sich konse-quent am Postulat des monetären Erfolgs orientieren. Die Formulierung dieses wirtschaftlichen Ziels lautet Gewinnmaximierung, dessen Realisierung aber Nebenbedingungen zu beachten hat. Eine aktuell herausfordernde Bündelung von Nebenbedingungen besteht in Form von Risiken der künstlichen Intelli-genz (KI). Aus diesem Grund existiert das Risikomanagement, um nicht hand-habbare Unsicherheiten weitestgehend in kontrollierbare Risiken zu überfüh-ren. Diese Systematik ist wiederum in den größeren Kontext der Corporate Governance eingebunden, der insgesamt unter Berücksichtigung der neuen technologischen Herausforderungen ausgestaltet sein muss. Eine KI-Governance auf der Grundlage des OECD-Ansatzes soll dabei helfen, die Notwendigkeiten und Prinzipien zu verstehen, um ein angemessenes KI-Risikomanagement auf Basis des NIST-Rahmenwerks durchführen zu kön-nen. Für ein besseres Verständnis, wie stark die Herausforderungen mittlerweile geworden sind, wird auf vier verschiedene Taxonomien zurückgegriffen. Die strategische Darstellung thematisiert dabei auch ein Verständnis der generati-ven Sprachmodelle und deren Risiken
Deep Learning Based 6D Pose Estimation of Unknown Objects
No full text6D pose estimation of unknown objects is an unsolved research problem in computer vision. This contribution proposes a novel method for estimating an object's pose using a monocular camera and an artificially created point cloud from the geometric object data. Point cloud generation and pose estimation are done with deep learning methods, combining several neural network-based approaches in one system. This paper describes the architecture and methods and compares and evaluates several ideas
A Foresight study on Sustainable Disaster and Emergency Management SUDEM processes digitalisation: the European Higher Education and Life-Long Learning perspective
No full textUsability als Erfolgsfaktor digitaler Medienplattformen
No full textEntwicklungsfirmen stehen vor der Herausforderung, ihre digitalen Medienplattformen erfolgreich zu vermarkten. Mit einer zunehmenden funktionalen Parität der Plattformen wird insbesondere Usability als Differenzierungsmerkmal relevant. Gebrauchstaugliche Plattformen haben nachweislich höhere Akzeptanzraten, steigern das Arbeitsengagement und reduzieren Stress. Eine durchdachte Usability-Strategie ist somit nicht nur ein Designziel, sondern auch ein wesentliches Marketinginstrument. Vermarktungsstrategien mit Fokus auf Usability können in primäre, sekundäre und tertiäre Ansätze unterteilt werden. Primäre Strategien zielen darauf ab, Usability direkt zu steigern und das Auftreten von Nutzungsproblemen zu vermeiden. Sekundäre Präventionsmaßnahmen konzentrieren sich darauf, entstandene Usability-Probleme möglichst gut zu reduzieren. Tertiäre Vermarktungsstrategien zielen schließlich darauf ab, Unzufriedenheit durch negative Usability zu reduzieren und Vertrauen wiederaufzubauen
Mathematical Modeling of Binary and Multicomponent Distillation
No full textNumerous types of distillation processes are employed for multiple purposes. To comprehend and assimilate all of these, it is vital to have a comprehensive understanding of this procedure. Any process can be better understood and analyzed by its mathematical modeling. This chapter presents the distillation process and mathematical modeling methods. Different feed compositions are used to assess the process, including binary distillation (simple distillation), multicomponent distillation and batch and continuous operation. Making the necessary assumptions, defining the variables, formulating the mass and energy balance and then using preexisting mathematical formulas and equations to solve them yield the mathematical modeling of these processes. This aids in providing a clear-cut perception of the distillation process. In the petrochemical industry, distillation is used for crude oil fractionation and natural gas processing, separating crude oil into fractions like gasoline, kerosene and diesel and natural gas into methane, ethane, propane and butane