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Prompt-guided semantic verification with Vision Language Model :A post-detection framework for UAV-based vehicle detection in adverse weather conditions
No full textAccurate vehicle detection from aerial imagery is critical for many modern applications, yet conventional object detectors often struggle under adverse conditions such as snow, low light, and occlusion. This thesis presents a hybrid detection–verification system designed to enhance robustness in such environments. The proposed system integrates a custom YOLO-based detector (YOLOv11s) with the Vision Language Model Gemma-3, which serves as a post-detection verifier to filter false positives through prompt-guided semantic analysis.
Systematic prompt engineering was applied to guide Gemma-3 in interpreting visual content alongside contextual language cues, enabling it to assess the validity of detections. Multiple prompting strategies were systematically evaluated, including zero-shot prompting with manually authored and meta-generated prompts, as well as few-shot, region-based, chain-of-thought, and cascade prompting techniques. Among these, zero-shot prompting with meta-prompts and cascade prompting achieved the highest verification performance on the Nordic Vehicle Dataset (NVD), demonstrating superior precision in filtering false positives from YOLOv11s detections. Experimental results show that Vision Language Models, such as Gemma-3, demonstrate effective semantic verification under challenging Nordic weather conditions, significantly reducing false positives in UAV-based vehicle detection. The results show that verification performance strongly depends on prompt design, with well-scaffolded
prompts that support reasoning across visibility, terrain, and object plausibility. Overall, they provide a reliable post-detection layer, particularly valuable in scenarios where precision must be prioritized
Structured all-optical domain inversion in iron-doped lithium niobate
No full textRecently, a promising technique for all-optical domain inversion in photovoltaic lithium niobate by visible laser irradiation has been demonstrated. However, only Gaussian light beams have been used to induce the inversion process. Here, we successfully exploit this emergent technique with structured light to fabricate a variety of 2D domain patterns. We use amplitude-modulated continuous-wave visible laser light controlled by a spatial light modulator. Our analysis investigates the relationship between domain growth dynamics and exposure parameters. Domains are evaluated using 3D second-harmonic generation laser scanning microscopy, second-harmonic generation k-spectroscopy, and scanning electron microscopy. The results demonstrate that initial nanodomain growth aligns with crystallographic directions, while the final domain shapes are influenced by both the amplitude of the induction light field and the exposure duration. By controlling light exposure, we create uniform single and multiple spatially shaped domains with lateral extensions ranging from 300 nm to over 400 μm. The correlation between domain formation dynamics and second-harmonic nonlinear diffraction measurements indicates the effectiveness of this structuring method for shaping quasi-phase-matched optical processes
Use of the superficial inferior epigastric vein in breast reconstruction with a deep inferior epigastric artery perforator flap
No full textBackground: Autologous breast reconstruction is highly regarded in reconstructive surgery after mastectomy. DIEP flap reconstruction represents the gold standard for autologous breast reconstruction. The major advantages of DIEP flap reconstruction are its adequate volume, large vascular caliber and pedicle length. Despite reliable anatomy, there are procedures where the plastic surgeon's creativity is required, not only to shape the new breast, but also to overcome microsurgical challenges. An important tool in these cases is the superficial epigastric vein (SIEV). Methods: 150 DIEP flap procedures performed between 2018 and 2021 were retrospectively evaluated for SIEV use. Intraoperative and postoperative data were analyzed. Rate of anastomosis revision, total and partial flap loss, fat necrosis and donor site complications were evaluated. Results: In a total of 150 breast reconstructions with a DIEP flap performed in our clinic, the SIEV was used in 5 cases. The indication for using the SIEV was to improve the venous drainage of the flap or as a graft to reconstruct the main artery perforator. Among the 5 cases, no flap loss occurred. Conclusions: Use of the SIEV is an excellent method to expand the microsurgical options in breast reconstruction with DIEP flap surgery. It provides a safe and reliable procedure to improve venous outflow in cases of inadequate outflow from the deep venous system. The SIEV could also provide a very good option for fast and reliable application as an interposition device in case of arterial complications
Al-doped ZnO-Coated LiNi1/3Mn1/3Co1/3O2 Powder Electrodes: The Effect of a Coating Layer on The Structural and Chemical Stability of The Electrode / Electrolyte Interface
No full textLiNi1/3Mn1/3Co1/3O2 (NMC-111) is one of the most popular cathode materials in Li-ion batteries. However, chemical and structural instabilities of the cathode/electrolyte interface at high charge cut-off voltages cause capacity fading. Surface modifications using metal oxides are promising candidates to suppress capacity fading. Here a systematic study on the degradation mechanism of an uncoated NMC-111 powder electrode is presented. Moreover, the effect of an Al-doped ZnO (Al:ZnO) coating layer on the structural and chemical stabilities of NMC-111 electrode cycled at high charge cut-off voltages is analyzed using X-ray photoelectron spectroscopy, scanning electron microscopy and analytical transmission electron microscopy as well as electrochemical testing. The coating is applied to commercial NMC-111 powder using a microwave-assisted sol-gel synthesis method. In the case of uncoated NMC-111 electrodes, pitting corrosion due to hydrofluoric acid attacking the electrode surface, cation mixing, and an irreversible phase transformation from a trigonal layered to a rock-salt phase occurs, causing capacity fading. While, in the case of Al:ZnO – coated NMC-111 electrodes, pitting corrosion, cation mixing, and the irreversible phase transformation are mitigated. Therefore, the capacity retention and rate capability are improved as the coating layer protects the electrode surface from the direct electrolyte exposure
Das letzte Mittel staatlicher Gewalt: Juristische Rahmenbedingungen, Prävalenz und Forschungsstand zum polizeilichen Schusswaffengebrauch
No full textDer Beitrag gibt einen Überblick über die rechtlichen Rahmenbedingungen, die vorhandene Datengrundlage sowie den aktuellen Forschungsstand zum polizeilichen Schusswaffengebrauch. Zunächst werden die in Deutschland geltenden rechtlichen Rahmenbedingungen analysiert, unter denen Polizeikräfte von ihrer Schusswaffe Gebrauch machen dürfen, wobei sowohl die öffentlich-rechtliche Ermächtigung als auch die strafrechtliche Rechtfertigung betrachtet werden. Bei der Auswertung des Ausmaßes des Schusswaffengebrauchs werden sowohl die offiziellen Statistiken, beauftragt durch die Innenministerkonferenz, als auch zivilgesellschaftlich gesammelte Medienberichte herangezogen. Dabei zeigt sich, dass insbesondere die offizielle Dokumentation bislang unzureichend ist. Darüber hinaus wird innerhalb des Beitrags der gegenwärtige Forschungsstand referiert, wobei deutlich wird, dass die empirische Forschung in Deutschland noch am Anfang steht. Internationale Studien, insbesondere aus den USA, geben Hinweise auf relevante Forschungsperspektiven, etwa zu ethnischen Disparitäten oder der Rolle psychischer Erkrankungen im Zusammenhang mit polizeilichem Schusswaffengebrauch. Diese Erkenntnisse sind aufgrund unterschiedlicher rechtlicher und gesellschaftlicher Kontexte jedoch nur begrenzt übertragbar. Der Beitrag macht deutlich, dass mehr empirische Forschung zum polizeilichen Schusswaffengebrauch in Deutschland erforderlich ist – sowohl für den wissenschaftlichen Erkenntnisgewinn als auch zum Schutz aller in entsprechende Situationen involvierten Personen.This article examines the legal framework, empirical evidence, and current research on police firearm use. The analysis begins with a comprehensive review of German legal provisions governing police firearm deployment, encompassing both public law authorizations and criminal law justifications. To assess the prevalence of firearm use, the study synthesizes official statistics from the Standing Conference of Interior Ministers with media reports documented by civil society organizations in Germany. This comparative analysis reveals significant deficiencies in official documentation practices. The article then evaluates the current state of research, highlighting the nascent nature of empirical studies in Germany. While international research, particularly from the United States, offers valuable insights into crucial aspects such as ethnic disparities and the role of mental illness in police firearm incidents, the transferability of these findings is constrained by distinct legal and sociocultural contexts. This analysis underlines the urgent need for expanded empirical research on police firearm use in Germany, both to advance scholarly understanding and to enhance safety protocols for all parties involved
Early Endosomes Act as Local Exocytosis Hubs to Repair Endothelial Membrane Damage
No full textThe plasma membrane of a cell is subject to stresses causing ruptures that must be repaired immediately to preserve membrane integrity and ensure cell survival. Yet, the spatio-temporal membrane dynamics at the wound site and the source of the membrane required for wound repair are poorly understood. Here, it is shown that early endosomes, previously only known to function in the uptake of extracellular material and its endocytic transport, are involved in plasma membrane repair in human endothelial cells. Using live-cell imaging and correlative light and electron microscopy, it is demonstrated that membrane injury triggers a previously unknown exocytosis of early endosomes that is induced by Ca2+ entering through the wound. This exocytosis is restricted to the vicinity of the wound site and mediated by the endosomal soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) VAMP2, which is crucial for efficient membrane repair. Thus, the newly identified Ca2+-evoked and localized exocytosis of early endosomes supplies the membrane material required for rapid resealing of a damaged plasma membrane, thereby providing the first line of defense against damage in mechanically challenged endothelial cells
Harmonic morphisms, eigenfamilies, and symmetry
No full textDiese Dissertation behandelt harmonische Morphismen, Eigenfamilien und Minimalflächen.
Wir entwickeln neue Reduktionstheoreme für harmonische Morphismen und zeigen, dass
sie genau die horizontal konformen Abbildungen sind, die bestimmte minimale
Untermannigfaltigkeiten zurückziehen. Außerdem analysieren wir globale und infinitesimale
Bedingungen für weitere Kodimensionen. Es folgt eine Strukturtheorie für Eigenfamilien auf
kompakten Riemannschen Mannigfaltigkeiten. Weiter untersuchen wir polynomielle
harmonische Morphismen zwischen euklidischen Räumen. Neue Beispiele und
Klassifikationen in niedrigen Dimensionen werden präsentiert. Abschließend wenden wir
unsere Theoreme an, um neue minimale Kegel zu erzeugen
Overcoming biodiversity blindness: Secondary data in primary citizen science observations
No full text1. In the face of the global biodiversity crisis, collecting comprehensive data and making the best use of existing data are becoming increasingly important to understand patterns and drivers of environmental and biological phenomena at different scales. 2. Here we address the concept of secondary data, which refers to additional information unintentionally captured in species records, especially in multimedia-based citizen science reports. We argue that secondary data can provide a wealth of ecologically relevant information, the utilisation of which can enhance our understanding of traits and interactions among individual organisms, populations and biodiversity dynamics in general. 3. We explore the possibilities offered by secondary data and describe their main types and sources. An overview of research in this field provides a synthesis of the results already achieved using secondary data and different approaches to information extraction. 4. Finally, we discuss challenges to the widespread use of secondary data, such as biases, licensing issues, use of metadata and lack of awareness of this trove of data due to a missing common terminology, as well as possible solutions to overcome these barriers. 5. Although the exploration and use of secondary data is only emerging, the many opportunities identified show how these data can enrich biodiversity research and monitoring
Stealthy Hyperuniform Surface Structures for Efficiency Enhancement of Organic Solar Cells
No full textLow absorption in the thin active layer of conventional organic solar cells limits their power conversion efficiency. Structured surface layers are a common approach to diffracting incoming light, thus elongating its path through the active layer, thereby increasing the probability of absorption and hence the power conversion efficiency. While standard periodic structures diffract light into discrete angles, making them optimal only for specific wavelengths, random structures induce broadband, but nontailorable diffraction. Thus, instead, a stealthy hyperuniform structure, designed to exhibit beneficial diffraction properties is implemented: it directs the light into a predefined range of higher angles, prevents diffraction into small angles, and is thus ideal for a strong active path length enhancement. After numerical optimization of the feature height and diameter, the stealthy hyperuniform structure is fabricated in silicon by electron beam lithography and subsequently transferred into a transparent polymer via replica molding. Experimental diffraction images reveal a circular symmetric spectrum, inducing diffraction independent of the azimuthal angle and polarization of the incident light. The application of the stealthy hyperuniform structure on a poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5′,7′-bis(2-ethylhexyl)benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione)]:3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d’]-s-indaceno[1,2-b:5,6-b′]dithiophene organic solar cell leads to a sharp increase in current density and power conversion efficiency
Supply chain network resilience:a guideline for investigating and adapting the structure of supply chain networks for resilience
No full textEreignisse der letzten Jahre wie die Corona-Pandemie oder die Blockade des Suez Kanals haben gezeigt wie störungsempfindlich moderne Lieferketten sind. Bestehend aus einem komplexen Netz an Zulieferern und Produktionsstandorten wird es nahezu unmöglich konkrete Risiken zu identifizieren und zu beseitigen. Stattdessen ist es wichtig die Resilienz von Lieferketten zu stärken, welche es ihnen erlaubt die direkten Folgen von Störungen abzumildern und sich schnell von den negativen Konsequenzen zu erholen. Diese Dissertation untersucht das Konzept der Lieferkettenresilienz mit Hilfe der Graphentheorie, welche es erlaubt Strukturen von Lieferketten zu modellieren, im Hinblick auf Schwachstellen zu analysieren und mit Hilfe geeigneter Algorithmen zu verbessern. Besonderen Wert wird hierbei daraufgelegt, die Ergebnisse mit realen Datensätzen zu evaluieren.The events of recent years, such as the COVID-19 pandemic or the blockage of the Suez Canal, have shown how vulnerable modern supply chains are to disruptions. Consisting of a complex network of suppliers and production sites, it becomes nearly impossible to identify and eliminate specific risks. Instead, it is crucial to strengthen the resilience of supply chains, allowing them to mitigate the immediate consequences of disruptions and recover quickly from their negative effects. This dissertation explores the concept of supply chain resilience using graph theory, which allows for the modeling of supply chain structures, analyzing them for weaknesses, and improving them through appropriate algorithms. Special emphasis is placed on evaluating the results with real-world datasets