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Organic form and evolution: the morphological problem in twentieth-century italian biology
No full textThis paper examines the efforts in evolution research to understand form’s structure that developed in Italy during the first half of the twentieth century. In particular, it analyzes how the organic approach in biology and the study of organic form merged in the morphological research agendas of Giuseppe Colosi (1892–1975) and Giuseppe Levi (1872–1965). These biologists sought to understand form’s inner composition and structure. First, I will briefly outline the morphological practices and frameworks used to study form changes and structures in the early twentieth century. Second, I will discuss what the Italian biologist Antonio Pensa (1874–1970) called the morphological problem. Third, I will examine Colosi’s response to the morphological problem. Fourth, I will analyze Levi’s morphological research program. As a result, this paper paves the way for a more nuanced and varied picture of the so-called "organicism movement" in the first half of the twentieth century by calling attention to morphology as practiced in Italian-speaking biology. In fact, alongside dialectical materialism and holistic biology, two of the main strands within organicism, the architectural approach to evolution as practiced in Italy and elsewhere had a profound impact on twentieth- and twenty-first-century organicism specifically and on evolutionary biology generally
„Diego ist tot, es lebe Diego!“ – Soziologische Beobachtungen zur ungebrochenen Popularität Maradonas in Argentinien
No full textIm November 2020 starb Diego Armando Maradona. Das öffentliche Trauergeschehen und die Kommunikation in Reaktion auf seinen Tod verdeutlichen den außerordentlichen Symbolwert Maradonas in Argentinien auf besondere Weise. Betrachtet man jedoch die Vielzahl an Eskapaden, Regelverstößen, Gesetzesbrüchen und sonstigen Grenzüberschreitungen Maradonas, erscheinen seine fast ungebrochene Popularität und regelrecht sakrale Überhöhung zu Lebzeiten und über den Tod hinaus in einem anderen Licht. Neben seinen beiden Dopingfällen, Schlägereien auf dem Fußballplatz oder obszönen Gesten gegen sportliche Kontrahenten ist gerade auch die Liste seiner außersportlichen Verfehlungen lang. Erklärungsbedürftig ist dabei nicht nur, wie Maradona trotz aller Skandale Held bleiben konnte, sondern auch, in welchem Maße die Widersprüche, Ambivalenzen und Unzulänglichkeiten seinen Heldenstatus erst erzeugten. Aus diesem Grund werden im vorliegenden Beitrag die Leitsemantiken, Legitimationsrhetoriken, Neutralisierungstechniken, Rechtfertigungsgeschichten und sonstigen Präfigurationen identifiziert, die im allgemeinen Reden über Maradona wiederkehrend auftauchen. Es wird gezeigt, wie Gemeinschaftsfiktionen, Protestsymbole, Geniekonzept, Opfernarrative und Gottessemantik seinen Heldenstatus kommunikativ immunisieren, kontrafaktisch stabilisieren und zusätzlich befördern
Fatigue life design of components under variable amplitude loading with respect to cyclic material behaviour
No full textLoad carrying components are subjected to variable amplitude loading for an extensive proportion of their life time. The available methods for fatigue life design can be divided into global and local approaches with reference to the system in which they evaluate the stress vs. endurance relation. The so called material based approach considers the elastic-plastic material behaviour through a combination of the local and the global approach, improving the transferability of material fatigue properties to arbitrary geometries while reducing the numerical effort for fatigue life estimation
Ernst May: Städtebauer, Visionär und Kosmopolit
No full textDas Städtebauprojekt »Neues Frankfurt«, der Wiederaufbau Wiesbadens und die »Siedlung Kranichstein« sind eng mit dem Namen Ernst Georg May verbunden. Auch an der TH Darmstadt hinterließ er als Dozent für Städtebau in der Fakultät für Architektur seine Spuren
Deep learning study of induced stochastic pattern formation in the gravure printing fluid splitting process
No full textWe use deep learning (DL) algorithms for the phenomenological classification of Saffman-Taylor-instability-driven spontaneous pattern formation at the liquid meniscus in the fluid splitting in a gravure printing press. The DL algorithms are applied to high-speed video recordings of the fluid splitting process between the rotating gravure cylinder and the co-moving planar target substrate. Depending on rotation velocity or printing velocity and gravure raster of the engraved printing cylinder, a variety of transient liquid wetting patterns, e.g., a raster of separate drops, viscous fingers, or more complex, branched liquid bridges appear in the printing nip. We discuss how these patterns are classified with DL methods, and how this could serve the identification of different hydrodynamic flow regimes in the nip, e.g., point or lamella splitting
Johnson, J. (2021). Artificial Intelligence and The Future of Warfare. The USA China and Strategic Stability. Manchester: Manchester University Press, 240 S., ISBN: 978-1526145055, € 90,72.
No full textTechnological and scientific progress, especially the rapid development of information technology (IT), plays a crucial role in peace and security issuesFootnote1. Artificial Intelligence (AI) is one example. AI is a sub-discipline of computer science, dealing with computer systems capable of performing tasks which require human intelligenceFootnote2. According to James Johnson, PhD, Lecturer in Strategic Studies in the Department of Politics & International Relations at the University of Aberdeen and author of the book Artificial Intelligence and the Future of Warfare, the hype around this has made it easy to overstate the opportunities and challenges posed by the development and deployment of AI in the military sphere. The author argues, that “speculations about super intelligent AI or the threat of superman AI to humanity” are entirely disconnected from today’s capabilities of AI. The book aims to address this problem by deciphering “proven capabilities and applications from mere speculation”, with a strong focus on the challenges AI poses to strategic stability, nuclear deterrence and how AI might influence nuclear weapon systems. The author concludes with implications and policy recommendations on how states could manage the escalatory risks posed by AI
Ls(Lq)-estimates of the pressure - The proof of Sohr-von Wahl and its impact on mathematical fluid dynamics
No full textThe article On the regularity of the pressure of weak solutions of Navier–Stokes equations by H. Sohr and W. von Wahl (1986) is one of the most-cited papers of the journal Archiv der Mathematik. Our aim is to describe not only the content of the paper, but especially the novelty of its results on maximal regularity of the Stokes operator considered from a point of view of the eighties and from a modern point of view
DEMO: Illuminating the BlindSpot: Efficient Single-Node Selective Jamming for LoRaWAN
No full textLoRaWAN has become a widely adopted, cost-effective solution for Low-Power Wide-Area Networks (LPWANs), bridging the gap between short-range wireless protocols and high-power cellular networks. Its affordable hardware and robust physical layer make it a key enabler for Internet of Things (IoT) applications across sectors like agriculture, smart cities, and industrial automation-domains where security is of central importance. Investigating LoRaWAN's resilience against physical-layer attacks, we developed BlindSpot, a novel jamming attack targeting state-of-the-art LoRaWAN gateways. Unlike traditional jammers, BlindSpot does not rely on overpowering transmissions but prevents their reception by exhausting resources at the gateway. This is possible since commercial gateway processors have only a limited number of demodulators for parallel frame reception. In this demo, we show the effectiveness of the attack against a commercial LoRaWAN gateway, compare it to traditional jamming, and show how our Software-Defined Radio (SDR)-based receiver can overcome the attack
Multi-Person Pose Tracking Using Dynamically Gated Similarities
No full textHuman pose tracking is a crucial task for many applications, such as human-robot interaction or video surveillance. Most current methods use a tracking-by-detection approach, which has shown to be very successful. These methods either use the location and movement of the detected humans or their visual appearance to track them. In recent years, some models started using heuristic approaches to combine both the pose and the appearance information. Even these newer models are still using fixed weights for these combinations. Therefore, the weights are dataset-dependent and need to be tuned for each dataset.
In this thesis, we propose a new model that uses dynamically learned weights to combine the pose, appearance, and or other information. The so-called Dynamically-Gated Similarities (DGS) model is highly modular and customizable. Weights can be used and trained mostly dataset independent. Additionally, the weights are computed individually for every detection, allowing the model to adapt more freely to the current situation. The DGS model is evaluated on the PoseTrack21 and the DanceTrack datasets. The proposed algorithm does not outperform current state-of-the-art models due to the simplicity of the used parts, but it is shown that dynamically learned weights can increase the tracking performance of the basic modules slightly.
The implementation and results will be made publicly available at: https://github.com/bmmtstb/dynamically-gated-similarities. The modules are structured in a way that they can be easily replaced by more complex models, which should increase the overall performance of the dynamically gated similarities model. Thus, this thesis only provides a proof of concept and baseline models for the dynamically gated similarities algorithm
Precise Resonance Frequency Tracking Based on a DSP-Implemented Virtual Vector Voltmeter
No full textMaintaining the resonance frequency of high-power ultrasound transducers is essential for applications such as sonochemistry, acoustic levitation and acousto-optic manipulation. This work presents a method to achieve resonance frequency tracking using a digital signal processor (DSP) implemented virtual vector voltmeter (VVV) for accurate phase detection. The system integrates three subsystems: a DSP for signal generation and phase detection, a microcontroller for control algorithms, and a custom PCB for signal amplification and measurement. Phase detection accuracy was evaluated over target phases from -5° to +5° using two bolt-clamped Langevin transducers with resonant frequencies of 28 kHz and 40 kHz, respectively. A 50-minute long-term performance test with the 40 kHz transducer showed phase tracking errors within ±0.35°, with maximum phase measurement uncertainties of ±0.0229° at 28 kHz and ±0.0213° at 40 kHz. These results demonstrate the DSP-implemented VVV’s ability to maintain precise phase tracking and resonance frequency adjustment, ensuring optimal performance in various ultrasound applications