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Fast determination of the monostatic radar channel in the near-field of electrically large targets
No full textThis contribution addresses the determination of the radar channel when operating in the near field of electrically large targets, which is a common scenario in modern short-range radar applications such as vital-sign sensing. With the focus on computational simplicity and the inclusion of near-field scattering phenomena, the proposed approach combines physical optics (PO) concepts and the far-field radiation pattern of the radar antenna to determine both amplitude and phase of the receive signal. The numerical implementation relies on basic scalar evaluations. The agreement between the simulated and measured radar channel of a metallized human-body-shaped object at 24 GHz and 61 GHz proves the effectiveness of the approach
Material mechanisms of the nanostructured metallic multilayer post-weld treatment for fatigue strength increase
No full textWhile traditional post weld treatments intend to reduce the fatigue failure potential by changing the weld seam geometry, introduction of compressive residual stresses and shielding off environmental impacts, the novel nanostructured metallic multilayer (NMM) post-weld treatment covers all three mechanisms simultaneously. NMM offer combined high strength and ductility and a significantly enhanced fatigue resistance. In a recent study a strong enhancement in fatigue resistance was detected. Utilizing energy-dispersive X-Ray diffraction techniques at the P61A-beamline at the German Synchrotron (DESY), it was found that residual stresses generated during the deposition process play a crucial role in this enhancement. Specifically, tensile stresses within the nanolaminate induce beneficial compressive stresses in the underlying substrate, effectively inhibiting fatigue crack initiation and resulting in an unprecedented increase in fatigue strength. NMM treatment of the double-V weld increases the fatigue strength from FAT class 80 to 225. This paper investigates which process parameters optimize the compressive stress profile in the steel base material, paving the way for the NMM post-weld treatment to reliably and economically contribute to longevity of cyclically loaded metal infrastructure
Gender and age-related decline in lower limb standing muscle strength: benchmarking for rehabilitation assessment
No full textThis study aimed to demonstrate a novel sensor-based measuring stand for objective assessment of multi-directional lower limb muscle strength and to establish essential, age- and gender-stratified normative benchmarks. This cross-sectional study measured relative leg strength (N/kg) across six standing movements in 99 healthy, non-professional athletes (males and females aged 20–30, 40–50, and 60–70 years). Results confirmed that men exhibited significantly greater strength than women across all six directions (17% to 35% difference). Furthermore, a marked age-related decline was consistently observed in both sexes, with the largest and most clinically relevant differences (often exceeding 30%) concentrated in the transition to the 60–70-year range. Methodologically, these findings are limited to demonstrating age-related differences rather than longitudinal decline and are specific to an active, healthy cohort. This study demonstrates the sensor-based stand as an efficient, objective tool for comprehensive strength assessment, but its clinical utility is prospective and requires further validation against diverse and pathological patient populations
Multiplikator:innen der kulturellen Bildung - Länderportrait Jugendkunstschulen in Schleswig-Holstein
No full textRadarbasierte Atemerfassung auf einer Palliativstation
No full textZusammenfassung: In der Palliativversorgung werden technische Hilfsmittel wie EKG oder Pulsoxymetrie nur sparsam eingesetzt, um Zuwendung und Beziehungsarbeit nicht zu stören. Gleichzeitig ist Symptomerkennung essenziell und viele Patient*innen können diese nicht selbst äußern. Diese Studie untersucht erstmals den Einsatz eines Radarsystems zum berührungslosen Atemfrequenzmonitoring bei Palliativpatient*innen.
In einer prospektiven Studie wurde radarbasiertes Atemfrequenzmonitoring mit einer Goldstandardmethode bei stationär behandelten Palliativpatient*innen verglichen.
Die Auswertung bei 13 Patient*innen zeigte eine Übereinstimmung der Atemfrequenzerfassungen durch Radar und Gold-Standardverfahren (n=13, Korrelation r=0,93; 88% der Atemfrequenzen innerhalb ±2 Atemzügen im Vergleich zu Goldstandard). Verlaufsanalysen ergaben Hinweise auf ein Potenzial zur Symptomerkennung.
Radarbasiertes Atemfrequenzmonitoring unter klinischen Bedingungen ist zuverlässig und hat das Potenzial, Symptome zu erkennen
Evaluating Magic Leap 2 controller tracking for sensor tool guidance in AR-based industrial inspections
No full textRigorous evaluation of commercial Augmented Reality (AR) hardware is crucial, yet public benchmarks for tool tracking on modern Head-Mounted Displays (HMDs) are limited. This paper addresses this gap by systematically assessing the Magic Leap 2 (ML2) controller’s tracking performance. Using a robotic arm for repeatable motion (EN ISO 9283) and an optical tracking system as ground truth, our protocol evaluates static and dynamic performance under various conditions, including realistic paths from a hydrogen leak inspection use case. The results provide a quantitative baseline of the ML2 controller’s accuracy and repeatability and present a robust, transferable evaluation methodology. The findings provide a basis to assess the controller’s suitability for the inspection use case and similar industrial sensor-based AR guidance tasks
Bernd Gössling, Antje Barabasch, Julia Bock-Schappelwein & Karin Heinrichs (2025) (Hrsg.): Berufsbildung in Zeiten des Mangels. Konferenzband zur 9. Berufsbildungsforschungskonferenz (BBFK)
No full textBerufsbildung in Zeiten des Mangels - Handlungserfordernisse neu denken: Unter diesem Leitthema stand die 9. Österreichische Berufsbildungsforschungskonferenz (BBFK), die vom 03. bis 05. Juli 2024 erstmals in Innsbruck stattfand. Der Tagungsband dokumentiert zentrale Ergebnisse der Konferenz und vereint 18 Fachbeiträge aus Vorträgen und Foren, ergänzt um drei Keynotes sowie Kurzbeiträge der beiden Preisträgerinnen des Berufsbildungsforschungspreises 2024. Er bietet Einblicke in aktuelle empirische Forschung, theoretische Perspektiven und praxisorientierte Ansätze der Berufsbildungsforschung und richtet sich an Forschende, Lehrende, Entscheidungsträger:innen in Bildungspolitik und -praxis sowie an alle, die an fundierten Analysen und zukunftsorientierten Impulsen zur Berufsbildung interessiert sind.Vocational training in times of shortage – rethinking the need for action: this was the theme of the 9th Austrian Vocational Training Research Conference (BBFK), which took place for the first time in Innsbruck from July 3 to 5, 2024. The conference proceedings document the key findings of the conference and bring together 18 specialist contributions from lectures and forums, supplemented by three keynotes and short contributions from the two winners of the 2024 Vocational Training Research Award. It offers insights into current empirical research, theoretical perspectives, and practice-oriented approaches to vocational education and training research and is aimed at researchers, teachers, decision-makers in education policy and practice, and anyone interested in well-founded analyses and forward-looking ideas on vocational education and training
An embedded computing approach for vibration-based system identification using reduced-order finite elements
No full textSystem identification (SID) constitutes a focal point in experimental testing of civil infrastructure as well as in structural health monitoring (SHM). Conventional SID approaches have relied on creating finite element (FE) models of civil infrastructure assets and on calibrating the models against in-situ derived information from testing equipment or against SHM data. FE models are capable of providing valuable information on the structural condition. However, the equations governing the FE method are coupled, usually calling for centralized data collection, which may be unsuitable for modern wireless SHM systems that employ independently operating wireless sensor nodes. In this paper, a SID approach for making full use of FE models on board wireless sensor nodes is presented, based on embedded computing and on reduced-order finite elements. Specifically, FE models of civil infrastructure assets are reduced, using model-order reduction, and partitioned into partial models, which represent different substructures and are computationally efficient for embedment in wireless sensor nodes. Using the partial models and structural response data from the substructures, insights into the structural condition of the civil infrastructure assets are obtained. The proposed approach is suitable for vibration-based SID, applied as part of long-term SHM strategies, and implementable in wireless SHM systems. Validation tests using SHM data recorded from a real-world road bridge showcase the validity of the proposed SID approach
Finding subdigraphs in digraphs of bounded directed treewidth
No full textIt is well known that directed treewidth does not enjoy the nice algorithmic properties of its undirected counterpart. There exist, however, some positive results that, essentially, present XP algorithms for the problem of finding, in a given digraph D, a subdigraph isomorphic to a digraph H that can be formed by the union of k directed paths (with some extra properties), parameterized by k and the directed treewidth of D. Our motivation is to tackle the following question: Are there subdigraphs, other than the directed paths, that can be found efficiently in digraphs of bounded directed treewidth? In a nutshell, the main message of this article is that, other than the directed paths, the only digraphs that seem to behave well with respect to directed treewidth are the stars. For this, we present a number of positive and negative results, generalizing several results in the literature, as well as some directions for further research