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Verlässliche Identifikation logistischer Entitäten anhand inhärenter visueller Merkmale
(2025) Rutinowski, Jérôme; Kirchheim, Alice; Müller, Emmanuel
Im industriellen Umfeld und insbesondere in der Logistikbranche ist die Kenntnis über den Aufenthaltsort von Gütern und die Möglichkeit der Identifikation ebenjener von großem Nutzen. Sofern diese Informationen erhoben werden, geschieht dies durch die Nutzung extrinsischer Merkmale, wie etwa Barcodes. Jedoch sind häufig kostengünstige Entitäten, wie etwa Paletten, bislang nicht serialisiert und können somit nicht über ihren Lebenszyklus verfolgt werden. Die Serialisierung dieser Entitäten anhand ihrer inhärenten visuellen Merkmale bringt jedoch erhebliche Vorteile hinsichtlich der Nachverfolgbarkeit und Prozessoptimierung mit sich. Die dadurch gewonnene Prozesstransparenz wiederum stärkt das Vertrauen in sonst intransparente Vorgänge. Diese Promotionsschrift befasst sich deshalb mit der Bearbeitung der beiden folgenden Forschungsziele: Das erste Forschungsziel dieser Arbeit ist die Identifikation logistischer Entitäten anhand ihrer inhärenten visuellen Merkmale. Hierbei sollen geeignete logistische Entitäten ausgewählt und entsprechende Datensätze erstellt werden. Anschließend werden verschiedene Identifikationsmethoden auf die Datensätze angewendet und verglichen. Das zweite Forschungsziel ist die erstmalige Definition und anschließende Quantifikation des Begriffs der Verlässlichkeit im Maschinellen Lernen im Allgemeinen und des Identifikationsverfahrens im Spezifischen. Es wird eine Definition des Begriffs basierend auf seinen Komponenten, die aus der relevanten Literatur deduziert werden, entwickelt und eine geeignete Quantifikationsmetrik erarbeitet. Zuletzt werden die erstellten Datensätze qualitativ evaluiert und die Identifikationsmethoden anhand ihrer Prädiktionsgenauigkeit bemessen. Es wird weiterhin ein industrienahes Szenario der Identifikation zur Evaluation der Umsetzbarkeit des Verfahrens umgesetzt. Wiederum werden die Definition und Quantifikationsmetrik der Verlässlichkeit anhand ihrer Reliabilität in der Nutzung von Experten evaluiert.
Engineering a synthetic RNA segregation system
(2023-01-22) Hürtgen, Daniel; Mascarenhas, Judita; Vibhute, Mahesh A.; Weise, Laura I.; Mayr, Viktoria S.; Sourjik, Victor; Mutschler, Hannes
Cells possess a number of active segregation machineries for both chromosomal and large extrachromosomal DNA elements to avoid stochastic loss during cell division. In contrast, system that can be exploited for active, general segregation of RNA molecules including mRNAs or self-replicating RNA constructs are currently lacking. Here, we present an artificial RNA segregation system derived from the bacterial type II ParMRC plasmid segregation system and the RNA coliphage MS2. We show that fusing the partition protein ParR with the MS2 RNA coat protein enables specific binding to microbeads decorated with RNA-repeats of the archetypical MS2 RNA operator hairpin. Addition of the actin homologue ParM protein triggers efficient and rapid microbeads segregation via ATP-dependent ParM polymerization. Our new RNA partitioning system could be used for specific localization of mRNAs and/or the stable maintenance of self-replicating RNA vectors in various contexts such as living and artificial cells.
Predictive modeling of lower extremity injury risk in male elite youth soccer players using least absolute shrinkage and selection operator regression
(2023-01-26) Kolodziej, Mathias; Groll, Andreas; Nolte, Kevin; Willwacher, Steffen; Alt, Tobias; Schmidt, Marcus; Jaitner, Thomas
Purpose:
To (1) identify neuromuscular and biomechanical injury risk factors in elite youth soccer players and (2) assess the predictive ability of a machine learning approach.
Material and Methods:
Fifty-six elite male youth soccer players (age: 17.2 ± 1.1 years; height: 179 ± 8 cm; mass: 70.4 ± 9.2 kg) performed a 3D motion analysis, postural control testing, and strength testing. Non-contact lower extremities injuries were documented throughout 10 months. A least absolute shrinkage and selection operator (LASSO) regression model was used to identify the most important injury predictors. Predictive performance of the LASSO model was determined in a leave-one-out (LOO) prediction competition.
Results:
Twenty-three non-contact injuries were registered. The LASSO model identified concentric knee extensor peak torque, hip transversal plane moment in the single-leg drop landing task and center of pressure sway in the single-leg stance test as the three most important predictors for injury in that order. The LASSO model was able to predict injury outcomes with a likelihood of 58% and an area under the ROC curve of 0.63 (sensitivity = 35%; specificity = 79%).
Conclusion:
The three most important variables for predicting the injury outcome suggest the importance of neuromuscular and biomechanical performance measures in elite youth soccer. These preliminary results may have practical implications for future directions in injury risk screening and planning, as well as for the development of customized training programs to counteract intrinsic injury risk factors. However, the poor predictive performance of the final model confirms the challenge of predicting sports injuries, and the model must therefore be evaluated in larger samples.
Aromatic volatile organic compounds absorption with phenyl-based deep eutectic solvents: a molecular thermodynamics and dynamics study
(2023-01-24) Yu, Gangqiang; Gajardo-Parra, Nicolás F.; Chen, Min; Chen, Biaohua; Sadowski, Gabriele; Held, Christoph
The suitability of phenyl-based deep eutectic solvents (DESs) as absorbents for toluene absorption was investigated by means of thermodynamic modeling and molecular dynamics (MD). The thermodynamic models perturbed-chain statistical associating fluid theory (PC-SAFT) and conductor-like screening model for real solvents (COSMO-RS) were used to predict the vapor–liquid equilibrium of DES–toluene systems. PC-SAFT yielded quantitative results even without using any binary fitting parameters. Among the five DESs studied in this work, [TEBAC][PhOH] consisting of triethyl benzyl ammonium chloride (TEBAC) and phenol (PhOH), was considered as the most suitable absorbent. Systems with [TEBAC][PhOH] had lowest equilibrium pressures of the considered DES–toluene mixtures, the best thermodynamic characteristics (i.e., Henry's law constant, excess enthalpy, Gibbs free energy of solvation of toluene), and the highest self-diffusion coefficient of toluene. The molecular-level mechanism was explored by MD simulations, indicating that [TEBAC][PhOH] has the strongest interaction of DES–toluene compared to the other DESs under study. This work provides guidance to rationally design novel DESs for efficient aromatic volatile organic compounds absorption.
Wetting behaviour of nickel-based brazing alloy BNi-5a on conventionally cast and laser-melted austenitic stainless steel 316L
(2024-10-30) Tillmann, Wolfgang; Bültena, Julia; Wojarski, Lukas; Zajaczkowski, Jonas; Donnerbauer, Kai; Walther, Frank
Laser beam melting is an additive manufacturing process that enables the production of highly complex components. In this process, metal powder is locally melted using a laser beam and built up layer by layer to form a physical component. Due to the layer-by-layer process manufacturing technique of the additive manufacturing process, the microstructure of a laser-melted 316L austenitic stainless steel differs from that of a conventionally cast material. For brazing technology, the different microstructure morphology is important because it affects the known wetting and diffusion behavior with a brazing filler metal, which affects the ability to produce high-strength brazed joints. Brazeability can be determined by examining the wetting of the brazing filler metal with the material to be joined. Therefore, this study investigates the wetting behavior of nickel-base brazing alloy BNi-5a on conventionally cast and laser-melted 316L austenitic stainless steel. Wetting tests were performed to evaluate the spreading area and wetting angle of BNi-5a on both 316L substrates. The wetting tests were performed in a high-temperature vacuum furnace at 1190 °C for 15 min. The results show that the laser-melted 316L stainless steel exhibits enhanced wettability compared to the conventionally cast material. This is related to a higher surface energy and a more pronounced diffusion mechanism called grain boundary grooving on the surface of the material.