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Ausgleichszahlung nach FluggastrechteVO bei vorweggenommener Beförderungsverweigerung auch ohne rechtzeitiges Einfinden zur Abfertigung (EuGH 26.10.2023 - C-238/22)
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Requirement analysis for an AI-based AR assistance system for surgical tools in the operating room: stakeholder requirements and technical perspectives
Abstract
Purpose
We aim to investigate the integration of augmented reality (AR) within the context of increasingly complex surgical procedures and instrument handling toward the transition to smart operating rooms (OR). In contrast to cumbersome paper-based surgical instrument manuals still used in the OR, we wish to provide surgical staff with an AR head-mounted display that provides in-situ visualization and guidance throughout the assembly process of surgical instruments. Our requirement analysis supports the development and provides guidelines for its transfer into surgical practice.
Methods
A three-phase user-centered design approach was applied with online interviews, an observational study, and a workshop with two focus groups with scrub nurses, circulating nurses, surgeons, manufacturers, clinic IT staff, and members of the sterilization department. The requirement analysis was based on key criteria for usability. The data were analyzed via structured content analysis.
Results
We identified twelve main problems with the current use of paper manuals. Major issues included sterile users’ inability to directly handle non-sterile manuals, missing details, and excessive text information, potentially delaying procedure performance. Major requirements for AR-driven guidance fall into the categories of design, practicability, control, and integration into the current workflow. Additionally, further recommendations for technical development could be obtained.
Conclusion
In conclusion, our insights have outlined a comprehensive spectrum of requirements that are essential for the successful implementation of an AI- and AR-driven guidance for assembling surgical instruments. The consistently appreciative evaluation by stakeholders underscores the profound potential of AR and AI technology as valuable assistance and guidance
Level-set-based topology optimization of threedimensional structures considering the manufacturing process with realistic milling tools
Abstract
In this work, we develop an approach for the level set based topology optimization of millable 3D structures. We focus on the 3-axis machining with realistic formed milling tools. The basis of the method lies in the identification of surface areas that cannot be reached by a given milling tool during optimization. For this purpose, we present an interpolation method that identifies these areas by an interpolation of the level set function along the outer contours of realistic milling tools, considering available machining directions. To minimize inaccessible surfaces, we define a potential field whose values decrease linearly into the outer normal direction of the structure. The inaccessible boundaries are pushed outward by minimizing their respective potential and therefore become accessible. Manufacturability is integrated into the optimization problem as an explicit constraint
Envisioning Secure and Private 6G-Enabled Cognitive Personal Informatics
This Paper explores how emergent technologies such as 6G and tactile Internet can potentially enhance cognitive, personal informatics (CPI) in participatory healthcare, promoting patient-centered healthcare models through high-speed, reliable communication networks. It highlights the transition to improved patient engagement and better health outcomes facilitated by these technologies, underscoring the importance of ultra-reliable, low-latency communications (URLLC) and realizing the tactile Internet’s potential in healthcare. This innovation could dramatically transform telemedicine and mobile health (mHealth) by enabling remote healthcare delivery while providing a better understanding of the inner workings of the patient. While generating many advantages, these developments have disadvantages and risks. Therefore, this study addresses the critical security and privacy concerns related to the digital transformation of healthcare. Our work focuses on the challenges of managing and understanding cognitive data within the CPI and the potential threats from analyzing such data. It proposed a comprehensive analysis of potential vulnerabilities and cyber threats, emphasizing the need for robust security frameworks designed with resilience in mind to protect sensitive cognitive data. We present scenarios for reward and punishment systems and their impacts on users. In conclusion, we outline a vision for the future of secure, resilient, and patient-centric digital healthcare systems that leverage 6G and the tactile Internet to enhance the CPI. We offer policy recommendations and strategic directions for stakeholders to create a secure, empowering environment for patients to manage their cognitive health information
Design, Manufacturing, Microstructure, and Surface Properties of Brazed Co-Based Composite Coatings Reinforced with Tungsten Carbide Particles
Brazing is a joining process that involves melting a filler metal and flowing it into the joint between two closely fitting parts. While brazing is primarily used for joining metals, it can also be adapted for certain coating deposition applications. The present study investigates the microstructure and corrosion behavior and sliding wear resistance of WC (Tungsten Carbide)-CoCr-Ni reinforced Co-based composite coatings deposited onto the surface of AISI 904L stainless steel using a vacuum brazing method. The primary objective of this experimental work was to evaluate the influence of WC-based particles added to the microstructure and the properties of the brazed Co composite coating. The focus was on enhancing the sliding wear resistance of the coatings while ensuring that their corrosion resistance in chloride media was not adversely affected. The morphology and microstructure of the composite coatings were investigated using scanning electron microscopy (SEM) and phase identification by X-ray diffraction (XRD). The SEM analysis revealed in the coating the presence of intermetallic compounds and carbides, which increase the hardness of the material. The sliding wear resistance was assessed using the pin-on-disk method, and the corrosion properties were determined using electrochemical measurements. The results obtained showed that as the WC particle ratio in the Co-based composite coating increased, the mechanical properties improved, the alloy became harder, and the tribological properties were improved. The evaluation of the electrochemical tests revealed no significant alterations of the manufactured composite in comparison with the Co-based alloys. In all cases, the corrosion behavior was better compared with that of the stainless-steel substrate
Steckbriefe zur Energiewende
In dem Bericht werden insbesondere auf Daten der Bundesnetzagentur (2022) basierende Steckbriefe sämtlicher bei der simulatorischen Behandlung der generellen Leistungsverhält-nisse in einem der geplanten Energiewende unterworfenen Energieversorgungssystem darge stellt. Die Steckbriefe umfassen die auftretenden Leistungsverläufe der Versorgung aus Photovoltaik, Windkraft, Biomasse usw. und des Verbrauchs mit Stromdirektverbrauchern, Wärmepumpen und Elektro-Fahrzeugen. Für den Verbrauch werden zwei Lastvarianten angegeben. Elektrolyseure sind in beiden Varianten nicht berücksichtigt, da sie trotz ihrer hohen Verluste dem Bereich der Wasserstoffspeicherung zugeordnet werden. Ebenso werden Wasserstoff-Kraftwerke weder dem Bereich der Erzeuger oder, aufgrund ihrer hohen Verluste, der Verbraucher zugeordnet; diese sind ebenfalls dem Bereich der Wasserstoffspeicherung zuzuordnen.
Die Leistungsverläufe werden ergänzt durch „Heatmaps“, mit deren Hilfe sich die Leistungsverläufe in vorteilhafter Weise tages- und stundenweise auflösen lassen. Im Gegensatz zur normalen Darstellung der Leistungsverläufe, aus denen sich saisonale Leistungsgänge und Leistungswerte sehr gut ablesen lassen, lassen sich aus diesen Heatmaps auch Tagesgänge aufgrund menschlicher Verhaltensweisen ermitteln. Statistiken zur Verteilung der Leistungswerte und Tabellen mit den wichtigsten Eckwerten der entsprechenden EE-Erzeuger und Verbraucher vervollständigen die Steckbriefe. In Einzelfällen werden noch Zusatzerläuterungen gegeben, ohne die sich die entsprechenden Steckbriefe unvollständig wären.
Insgesamt ergibt sich, dass der Stromverbrauch ab 2045 saisonal enorm ausgeprägte Maxima und Minima aufweist, die erheblich von den Maxima und Minima des heutigen Stromverbrauchs abweichen. Dies ist das Resultat des Stromverbrauchs aus Wärmepumpen und Elektro-Fahr-zeugen. Die Verbrauchsmaxima können dabei Werte von etwa 170 GW erreichen, was im Gegensatz zu heutigen Maxima von weniger als 90 GW als bemerkenswert bezeichnet werden muss.
In jedem Fall wird ein steuerbarer Backup-Kraftwerkspark benötigt, dessen kontinuierliche Verfügbarkeit während eines Tages größer wie 2 Stunden sein muss. Er muss gezielt zur Morgenzeit, typischerweise zwischen 05:00 und 07:00, mit Leistungshüben von 20 GW/h eingeschaltet und abends, typischerweise zwischen 18:00 und 20:00, mit Lastabwürfen von über 22 GW/h gezielt wieder abgeschaltet werden können. Grund hierfür ist der Wechsel menschlicher Tagesaktivität auf Nachtpassivität und umgekehrt, was sich im täglichen Strombedarf widerspiegelt