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Design, synthesis, in silico studies, and antiproliferative activity of a novel series of thiazole/1,2,3-triazole hybrids as apoptosis inducers and multi-kinase inhibitors endowed with anti-breast cancer activity
No full textA novel series of thiazole/1,2,3-triazole hybrids has been developed and evaluated for their in vitro anticancer efficacy. Compounds 10c, 10e, 10k, 10m, 10n, and 10o exhibited superior anticancer efficacy against the evaluated cancer cell lines, demonstrating a favorable safety profile, particularly against MCF-7 breast cancer, compared to erlotinib. The in vitro anti-breast cancer assay of compounds 10e and 10k demonstrated potent antiproliferative activity against the MCF-7 breast cancer cell line, with IC values of 24 nM and 21 nM, respectively, relative to the reference erlotinib, which exhibited an IC value of 40 nM. To elucidate their antiproliferative mechanism, tests for EGFR, HER-2, VEGFR-2, and BRAF kinases were performed. Compounds 10e and 10k exhibited the highest potency as multi-EGFR/HER-2/VEGFR-2 kinase inhibitors, with IC values of 73 ± 4 nM (EGFR), 31 ± 2 nM (HER-2), and 20 ± 1 nM (VEGFR-2), and 69 ± 4 nM (EGFR), 29 ± 1 nM (HER-2), and 21 ± 1 nM (VEGFR-2), respectively. The BRAF inhibitory testing results indicated weak to moderate effectiveness for the evaluated compounds. Findings from assays of apoptotic markers (Bax, Bcl2, and p53) indicate that apoptosis may contribute to the antiproliferative effects of the examined compounds. Analysis revealed that the 1,2,3-triazole moiety, the para-substituted methoxy group, and the chalcone moiety are essential variables in enhancing activity. The in silico docking studies against EGFR, HER-2, and VEGFR-2 revealed the importance of the phenyl 1,2,3-triazole moiety and the chalcone side chain in anticancer activity. The most potent compounds demonstrated drug-like properties and could serve as prototypes for future optimization. Compounds 10e and 10k may serve as examples of multi-targeting anticancer agents that function by blocking the EGFR, HER-2, and VEGFR-2 kinases
STAR-APTV: Deep learning-enabled 3D flow reconstruction in evaporating multicomponent droplets
No full textMulticomponent droplet evaporation generates inherently three-dimensional, solutal-Marangoni flows that challenge single-camera velocimetry. We present STAR-APTV (Segmentation and Tracking Anything-based Robust Astigmatic Particle Tracking Velocimetry), a zero-shot, deep-learning-assisted, astigmatic particle tracking framework for time-resolved 3D-3C flow reconstruction with minimal optical hardware. We leverage zero-shot segmentation using SAM to detect particles in microscopic images without any task-specific labels or training. To characterize each detected particle under optical aberration, we combine shape-aware refinement using elliptic Fourier descriptors with intensity-based features within the refined mask region. We then estimate depth using an uncertainty-aware deep learning model, in which the estimated 3D trajectories are stabilized with a multi-object tracking algorithm and Kalman filter. Against a representative baseline (DefocusTracker), STAR-APTV detects up to six times more particles at high seeding density, while maintaining temporally coherent tracks, and preserving positional accuracy of particles in the presence of noise. Through synthetic validation, the proposed algorithm exhibited AEE = 0.077 px/frame and AAE = 1.45° in a known analytical flow field reconstruction. Experimental validation in two droplet regimes confirms robustness in complex, refractive samples and cross-setup transfer without any task-specific training. Among these flows, in the more challenging flow with relatively dense particle seeding, the detection rate was increased by nearly 70%, with increased retention rates and extended trajectories by almost three times compared to the conventional method. These results altogether demonstrate high-fidelity, single-camera, volumetric velocimetry in refractive, densely seeded environments, extending defocusing/astigmatic PTV toward complex droplet flows
Methode zur referenzbasierten Herstellkostenschätzung mit semantischen Technologien am Beispiel von Getriebekomponenten elektrischer Antriebssysteme = Method for reference-based manufacturing cost estimation using semantic technologies on the example of gear components for electric drive systems
No full textIn schwierigen Marktsituationen gestalten Unternehmen zur Sicherung der Profitabilität aktiv ihre Produktkosten. Dabei werden Herstellkostenschätzungen als Grundlage für Design- und Managemententscheidungen verwendet. Herstellkostenschätzungen erfordern fundiertes Wissen an der Schnittstelle zwischen Konstruktion und Fertigung und verursachen einen hohen manuellen Zeitaufwand bei der Erstellung. Daher ist das Ziel der vorliegenden Arbeit die Entwicklung einer Methode, die die Erstellung von Herstellkostenschätzungen durch die zielgerichtete Identifikation und Verwendung von Referenzsystemelementen unterstützt. Hierzu werden semantische Technologien eingesetzt.
Zunächst wird im Stand der Forschung ein Verständnis für das Modell der SGE – Systemgenerationsentwicklung nach Albers, das Cost Engineering und semantische Technologien geschaffen. Als nächstes werden Herausforderungen bei der Erstellung von Herstellkostenschätzungen in der Praxis identifiziert. Herauszuheben sind eine geringe Datenverfügbarkeit und Datenqualität, sowie ein fehlender Zusammenhang von Produkt- und Fertigungsinformationen. Darauf aufbauend wird iterativ die Cost Engineering Ontologie entwickelt, die detaillierte Zusammenhänge zwischen Komponenten und deren Fertigung beschreiben kann. Aufbauend auf der Cost Engineering Ontologie und dem Modell der SGE – Systemgenerationsentwicklung wird die Methode zur referenzbasierten Herstellkostenschätzung entwickelt. Der Mensch steht dabei im Mittelpunkt. Die Methode umfasst sechs Schritte: Bauteilinformationen erfassen, Referenz identifizieren, Prozesskette übernehmen und anpassen, Prozesskette in Herstellkosten überführen, Ergebnis prüfen und Ergebnis speichern. Anschließend wird ein Funktionsdemonstrator mit einem Softwareprototyp realisiert, der die Anwendung der Methode in der Praxis unterstützt. Der Softwareprototyp beinhaltet einen Wissensgraphen, der basierend auf der Cost Engineering Ontologie, am Beispiel von Getriebekomponenten für elektrische Antriebe erstellt wurde und die für die Methode notwendigen Zusammenhänge zwischen Bauteilen und Fertigung enthält. Mit dem Softwareprototyp ist es möglich, basierend auf einer STEP-Datei eines Bauteils, innerhalb einer Minute eine Herstellkostenschätzung zu erstellen.
Einer initialen Evaluation folgend, werden die Methode und der Softwareprototyp in einer Studie validiert. Dazu werden Interviews, Fragebögen und Beobachtungen verwendet. Während eine Reduktion des Zeitaufwandes verifiziert wird, kann eine positive Wirkung der Methode und des Softwareprototyps auf die Transparenz und die Wissensbasis nur eingeschränkt bestätigt werden. Insbesondere die automatisiert ablaufende Identifikation von Referenzsystemelementen und die Herstellkostenschätzung mit prozessspezifischen Kostenmodellen reduziert den manuellen Zeitaufwand bei der Erstellung von Herstellkostenschätzungen
Influence of the backbone chemistry and side-chain spacer flexibility in sodium single-ion conducting polymer electrolyte for sodium-batteries
No full textDecision support for energy system transformation – A systematic analysis of MADM software for sustainability assessment
No full textMulti-criteria decision analysis (MCDA) methods for sustainability assessment (SA) have been used in various decision-making processes for energy system transformation. However, concerns remain about the complexity and resource intensity of their application. The literature on MCDA and SA involves methodological advances and case studies, but lacks of systematic analysis of MCDA software for decision support. This study conducts a systematic analysis on multi-attribute decision making (MADM) software and their functionality for SA from a theoretical and user perspective. The users are SA practitioners with different levels of knowledge and expertise of MADM methods. The functionality is determined by a set of features gathered from a literature review of studies conducting SA with MADM software and from dedicated literature exploring the capabilities of MADM methods for SA. These features and capabilities are translated into assessment criteria and domains that encompass the entire MADM process, from supporting problem formulation and preference elicitation to robustness analysis. A sample of 25 free MADM software was assessed using 29 criteria across eight domains. Finally, recommendations are provided based on an effort estimation required to extend the software functionality. Results show that the MCDA community aims to provide practitioners with reliable free MADM software. However, weaknesses are identified in the software assessed, particularly in the functionality for stakeholder\u27s involvement, output variability analysis, and problem structuring. Collaborative initiatives involving SA practitioners, software developers and the MCDA community, can help to accordingly enhance MADM software for SA
Präferenzen und Verkehrsentwicklung mit automatisierten Fahrzeugen
No full textDer Schwerpunkt der Bearbeitung liegt auf der Ermittelung von relevanten verkehrlichen Verhaltensparametern, die anschliessend im Nationalen Personenverkehrsmodell des UVEK abgebildet werden. Dadurch sollen die zu erwartenden verkehrlichen Effekte einer Verbreitung von automatisierten Fahrzeugen in der Schweiz abgeschätzt werden. In einer Initialisierungsphase erfolgt eine detaillierte Analyse von relevanten und modellierbaren Parametern und Bevölkerungssegmenten auf Basis einer tiefgehenden Literaturstudie und Erkenntnissen aus anderen Projekten. In Abstimmung mit der Begleitkommission werden “Referenzsituationen” festgelegt, die im Mittelpunkt der Diskussionen in den Fokusgruppen stehen. Vorab-Fragebögen sowie Diskussions-Leitfäden (auch zur Ableitung eines ersten Code-Schemas für die spätere Auswertung der Diskussionen in den Fokusgruppen) werden ebenso erstellt wie ein Konzept für die Abbildung im Verkehrsmodell. Dies erfolgt in einer engen Abstimmung zwischen den erhobenen empirischen und strukturellen Aspekten des Verkehrsmodells. Dazu wird das Design der Studie verfeinert, um sicherzustellen, dass in der Empirie diejenigen Aspekte des automatisierten Fahrens erfragt werden, die zum einen heute (für die Schweiz) noch nicht erforscht sind und zum anderen im Verkehrsmodell auch abgebildet werden können
Online Motion Planning for Robot Manipulators in Dynamic Environments
No full textThis thesis focuses on the development of motion planning algorithms for dynamic environments. A dynamic environment is defined as one that evolves over time, necessitating that planning algorithms be efficient in terms of planning and replanning and capable of adapting to the robot\u27s current state and to potential changes in the environment.
To address these challenges, this thesis proposes three contributions, each targeting a different aspect of motion planning in dynamic settings.
In order to achieve efficient planning and replanning with short planning time and small variations, the first research question is formulated to address the bottleneck of speeding up motion planning methods. Since collision checking is a major bottleneck for rapid motion planning, a motion planning method is proposed to identify and eliminate unnecessary collision checks during planning.
This method uses a precomputed deterministic roadmap to capture the collision-free space of the static environment. It then performs a heuristic-informed search on the roadmap and introduces a novel safe zones concept for edge examination to find a feasible solution.
When exploring the precomputed roadmap for a solution, the heuristic-informed search minimizes the number of edge examinations by prioritizing edges based on heuristics derived from path costs in the roadmap. The concept of safe zones utilizes the spatial relation between the robot and the environment to identify regions that do not require collision checks. As a result, the method achieves both a reduced number of edge examinations and a decrease in collision checks for each examination.
Despite the significant speedup by reducing the number of collision checks, the planning time naturally increases with problem complexity and remains unbounded. The second contribution is a method to generate subgoals for decomposing complex motion planning problems into small, easily solvable subproblems. Iteratively planning the subproblems ensures short planning time in dynamic environments. This method begins with a pipeline to collect a dataset of suitable subgoals, which can be planned within a specific bounded time. Using this dataset, a conditional generative model captures the distribution of subgoals based on the given planning problems. During inference, a time estimator acts as a critic to evaluate whether the generated subgoals can meet the desired time constraints and lead the robot toward the final goal. Based on this evaluation, the proposed method makes informed decisions to select a suitable subgoal for planning.
The contributions above solely consider the current geometric state of dynamic environments and overlook the temporal aspect. This short-sightedness over the time horizon can result in frequent replanning and local-minima issues. The third contribution addresses this issue by using episodic reinforcement learning to implicitly account for potential changes in the environment over time. The learned policy refines reference trajectories based on the dynamic environment.
Three trajectory refinement strategies based on B-spline movement primitives are introduced to modify the reference trajectories while ensuring smooth trajectory transitions. The planning results of the contributions above can be used as reference trajectories. This spatiotemporally aware method achieves superior task performance compared to methods that solely depend on geometric information and other spatiotemporal planners.
Comprehensive evaluations and ablation studies in simulation and real robot experiments are conducted to demonstrate the effectiveness and limitations of the proposed methods
