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Item Determination of correlated color temperature in ex vivo porcine eyes during intraocular illumination(Technische Hochschule Ulm, 2023-04-21) Fehler, Nicole; Hessling, Martin(1) Background: In ophthalmic surgery, white light is mostly applied to illuminate the intraocular space, and ophthalmologists are comfortable working with it. Diaphanoscopic illumination changes the spectral composition of light, resulting in a change in the correlated color temperature (CCT) of the intraocular illumination. This color change makes it difficult for surgeons to recognize the structures in the eye. CCT during intraocular illumination has not yet been measured before, and it is the aim of this study to perform such measurement. (2) Methods: CCT was measured inside ex vivo porcine eyes during diaphanoscopic illumination and endoillumination using a current ophthalmic illumination system with a detection fiber inside the eye. By applying pressure on the eye with a diaphanoscopic fiber, the dependency of CCT on pressure was examined. (3) Results: The intraocular CCT values during endoillumination were 3923 K and 5407 K for the halogen and xenon lamps, respectively. During diaphanoscopic illumination, a strong unwanted red shift was observed, resulting in 2199 K and 2675 K for the xenon and the halogen lamps, respectively. Regarding different applied pressures, the CCT did not differ considerably. (4) Conclusions: This red shift should be compensated for in the development of new illumination systems since surgeons are used to white light illumination, which also simplifies the identification of retinal structures.Item Luminous flux in ex-vivo porcine eyes during endoillumination and during transscleral illumination depending on the transmission properties of the eyewall(Technische Hochschule Ulm, 2023-03-23) Fehler, Nicole; Hessling, Martin(1) Background: During eye surgery, it is important that sufficient light enlightens the inside of the eye for small structures to become visible. The intraocular brightness is influenced by the luminous flux of the illumination system. However, the intraocular luminous flux during surgery has not been investigated so far. Insufficient luminous flux makes vision difficult for the surgeon, whereas excessive luminous flux can cause damage to the retina. Therefore, the luminous flux in lightly and strongly pigmented eyes is determined by endoillumination and diaphanoscopic illumination. (2) Methods: First, the luminous flux emitted from a diaphanoscopic illumination fiber is measured. For determining the intraocular luminous flux, this is multiplied with the transmission properties of the eyewall, which are determined for ex vivo porcine eyes. In order to compare the luminous flux of transscleral illumination with that of endoillumination, the luminous flux of various endoillumination fibers is examined. (3) Results: The results reveal that the total transmission of the eyewall is up to 2.5 times higher for blue/lightly pigmented eyes than for brown/strongly pigmented eyes. With this, the intraocular luminous flux in ex vivo porcine eyes is around 95% higher for less pigmented eyes than for strong pigmented eyes, considering intraocular reflections. (4) Conclusion: To obtain the same brightness in blue and brown eyes, the surgeon can reduce the intensity of the light source when illuminating blue eyes to reduce their retinal risk.Item Enhanced cellular migration and prolonged chondrogenic differentiation in decellularized cartilage scaffolds under dynamic culture conditions(Technische Hochschule Ulm, 2021-10-23) Goldberg-Bockhorn, Eva; Wenzel, Ulla; Theodoraki, Marie-Nicole; Döscher, Johannes; Riepl, Ricarda; Wigand, Marlene C.; Brunner, Cornelia; Hessling, Martin; Hoffmann, Thomas K.; Kern, Johann; Rotter, NicoleLesions of aural, nasal and tracheal cartilage are frequently reconstructed by complex surgeries which are based on harvesting autologous cartilage from other locations such as the rib. Cartilage tissue engineering (CTE) is regarded as a promising alternative to attain vital cartilage. Nevertheless, CTE with nearly natural properties poses a significant challenge to research due to the complex reciprocal interactions between cells and extracellular matrix which have to be imitated and which are still not fully understood. Thus, we used a custom-made glass bioreactor to enhance cell migration into decellularized porcine cartilage scaffolds (DECM) and mimic physiological conditions. The DECM seeded with human nasal chondrocytes (HPCH) were cultured in the glass reactor for 6 weeks and examined by histological and immunohistochemical staining, biochemical analyses and real time-PCR at 14, 28 and 42 days. The migration depth and the number of migrated cells were quantified by computational analysis. Compared to the static cultivation, the dynamic culture (DC) fostered migration of HPCH into deeper tissue layers. Furthermore, cultivation in the bioreactor enhanced differentiation of the cells during the first 14 days, but differentiation diminished in the course of further cultivation. We consider the DC in the presented bioreactor as a promising tool to facilitate CTE and to help to better understand the complex physiological processes during cartilage regeneration. Maintaining differentiation of chondrocytes and improving cellular migration by further optimizing culture conditions is an important prerequisite for future clinical application.Item Disinfection properties of conventional white LED illumination and their potential increase by violet LEDs for applications in medical and domestic environments(Technische Hochschule Ulm, 2021-04-30) Buehler, Jule; Sommerfeld, Florian; Meurle, Tobias; Hönes, Katharina; Hessling, MartinThe antimicrobial impact of visible violet and blue light has been known for more than a century but hardly been applied for purposeful pathogen reduction or prevention. The disinfecting properties of wide-spread warm-white and cool-white light emitting diodes (LEDs) are investigated by irradiation of staphylococci with different LEDs and varying doses. Additionally, the combination of a white and a violet LED illumination is examined. Both white LEDs exhibit an antimicrobial effect, which seems to be dominated by the blue parts of the LED emissions. Unfortunately, the antimicrobial effect is weak in realistic illumination applications. Additional violet LEDs can significantly enhance this impact without a large change in human color perception. This allows reasonable applications in certain medical and domestic environments without endangering humans.Item Comparison of different far-UVC sources with regards to intensity stability, estimated antimicrobial efficiency and Potential Human Hazard in Comparison to a Conventional UVC Lamp(Universität Ulm, 2024-11-19) Sicks, Ben; Maiss, Florian; Lingenfelder, Christian; Wiegand, Cornelia; Hessling, Martin; Giannetti, AmbraThe recently much noticed Far-UVC spectral range offers the possibility of inactivating pathogens without necessarily posing a major danger to humans. Unfortunately, there are various Far-UVC sources that differ significantly in their longer wavelength UVC emission and, subsequently, in their risk potential. Therefore, a simple assessment method for Far-UVC sources is presented here. In addition, the temporal intensity stability of Far-UVC sources was examined in order to reduce possible errors in irradiation measurements. For this purpose, four Far-UVC sources and a conventional Hg UVC lamp were each spectrally measured for about 100 h and mathematically evaluated for their antimicrobial effect and hazard potential using available standard data. The two filtered KrCl lamps were found to be most stable after a warm-up time of 30 min. With regard to the antimicrobial effect, the radiation efficiencies of all examined (Far-) UVC sources were more or less similar. However, the calculated differences in the potential human hazard to eyes and skin were more than one order of magnitude. The two filtered KrCl lamps were the safest, followed by an unfiltered KrCl lamp, a Far-UVC LED and, finally, the Hg lamp. When experimenting with these Far-UVC radiation sources, the irradiance should be checked more than once. If UVC radiation is to be or could be applied in the presence of humans, filtered KrCl lamps are a much better choice than any other available Far-UVC sources.Item DilatedToothSegNet: tooth segmentation network on 3D dental meshes through increasing receptive vision(Universität Ulm, 2024-03-05) Krenmayr, Lucas; Schwerin, Reinhold von; Schaudt, Daniel; Riedel, Pascal; Hafner, AlexanderThe utilization of advanced intraoral scanners to acquire 3D dental models has gained significant popularity in the fields of dentistry and orthodontics. Accurate segmentation and labeling of teeth on digitized 3D dental surface models are crucial for computer-aided treatment planning. At the same time, manual labeling of these models is a time-consuming task. Recent advances in geometric deep learning have demonstrated remarkable efficiency in surface segmentation when applied to raw 3D models. However, segmentation of the dental surface remains challenging due to the atypical and diverse appearance of the patients’ teeth. Numerous deep learning methods have been proposed to automate dental surface segmentation. Nevertheless, they still show limitations, particularly in cases where teeth are missing or severely misaligned. To overcome these challenges, we introduce a network operator called dilated edge convolution, which enhances the network’s ability to learn additional, more distant features by expanding its receptive field. This leads to improved segmentation results, particularly in complex and challenging cases. To validate the effectiveness of our proposed method, we performed extensive evaluations on the recently published benchmark data set for dental model segmentation Teeth3DS. We compared our approach with several other state-of-the-art methods using a quantitative and qualitative analysis. Through these evaluations, we demonstrate the superiority of our proposed method, showcasing its ability to outperform existing approaches in dental surface segmentation.Item Augmentation strategies for an imbalanced learning problem on a novel COVID-19 severity dataset(Universität Ulm, 2023-10-25) Schaudt, Daniel; von Schwerin, Reinhold; Hafner, Alexander; Riedel, Pascal; Reichert, Manfred; von Schwerin, Marianne; Beer, Meinrad; Kloth, ChristopherAbstract Since the beginning of the COVID-19 pandemic, many different machine learning models have been developed to detect and verify COVID-19 pneumonia based on chest X-ray images. Although promising, binary models have only limited implications for medical treatment, whereas the prediction of disease severity suggests more suitable and specific treatment options. In this study, we publish severity scores for the 2358 COVID-19 positive images in the COVIDx8B dataset, creating one of the largest collections of publicly available COVID-19 severity data. Furthermore, we train and evaluate deep learning models on the newly created dataset to provide a first benchmark for the severity classification task. One of the main challenges of this dataset is the skewed class distribution, resulting in undesirable model performance for the most severe cases. We therefore propose and examine different augmentation strategies, specifically targeting majority and minority classes. Our augmentation strategies show significant improvements in precision and recall values for the rare and most severe cases. While the models might not yet fulfill medical requirements, they serve as an appropriate starting point for further research with the proposed dataset to optimize clinical resource allocation and treatment. © In Copyright http://rightsstatements.org/vocab/InC/1.0/Item Inbetriebnahme und Weiterentwicklung eines Prüfstandes für die versuchsgestützte thermodynamische Untersuchung eines Druckwasserstoff-Speichersystems(Technische Hochschule Ulm, 2024-11-04) Mak, Pascal; Frenz, Hartmut; Schlick, Michael; Weiß, AlexandraDiese Abschlussarbeit bietet einen umfassenden Einblick in die Inbetriebnahme einer Prüfvorrichtung für einen Druckwasserstoff-Systemspeicher, konzipiert zur Durchführung einer Feuersicherheitsprüfung gemäß der Regelung Nr. 134 der Wirtschaftskommission der Vereinten Nationen für Europa. In den durchgeführten Prüfungen ist der Wasserstofftank drucklos und nicht befüllt. Um das Auslösen der thermischen Druckentlastungsvorrichtung zu registrieren, wurden das „On Tank Valve“ und das „End Plug“ modifiziert. Hauptziel dieser Arbeit war es, den Prüfstand in Betrieb zu nehmen und die Redundanz einer mittig verbauten thermischen Druckentlastungsvorrichtung nachzuweisen, um das Wasserstoffspeichersystem zu optimieren und die Produktionskosten zu senken. Die Arbeit gliedert sich in mehrere Phasen: Zunächst wird der Grundaufbau des Prüfstands und dessen Gefahrenpotenzial untersucht. Anschließend werden bauliche Veränderungen zur Veranschaulichung des Auslösezeitpunkts der thermischen Druckentlastungsvorrichtung beschrieben, eine optimierte Messtechnik entwickelt und im Versuchsaufbau implementiert. Die erzielten Ergebnisse werden ausgewertet und interpretiert, gefolgt von einer Verbesserungsanalyse des Versuchsaufbaus. Zusammenfassend zeigte die Inbetriebnahme des Prüfstandes für die Feuerprüfung des Wasserstofftanks wichtige Schwachstellen auf, die behoben werden müssen. Geplante Verbesserungen und zusätzliche Prüfungen sollen sicherstellen, dass der Prüfstand zukünftig zuverlässig und sicher arbeitet, um die strengen Anforderungen der Feuerprüfungen zu erfüllen. Trotz des Verbesserungspotenzials des Prüfstandes wird angenommen, dass die Hauptprüfungskonfiguration die Feuerprüfung bestehen könnte und ein Auslösen der thermischen Druckentlastungsvorrichtung bei ausreichender thermischer Widerstandsfähigkeit des Tanks wahrscheinlich ist.Item Dynamic allocation of service robot resources to an order picking task considering functional and non-functional properties(Technische Hochschule Ulm, 2022-07-11) Blender, Timo; Schlegel, ChristianIndustry 4.0 processes have often varying requirements. A service robot and a team of service robots respectively represent a flexible resource. That means, it possesses variability that can possibly be configured in such a way that it is able to fulfill the requirements of industry 4.0 processes. Determining whether that is the case and how that has to happen is an important part of variability management. Based on a model-driven general method for variability management in a robotics software ecosystem, we present here a concrete use case (model) in which we allocate for an order picking task with specific time requirements either a single fitting service robot or a collaboration of two fitting service robots. Relevant properties of the service robots considered are both functional (are the capabilities to execute the tasks available?) as well as non-functional (the desired velocity parameterization while executing the individual navigation sub tasks limited by the respective maximum speed of a service robot).Item Surface disinfection with white-violet illumination device(Technische Hochschule Ulm, 2022-04-02) Hessling, Martin; Meurle, Tobias; Hoenes, KatharinaThe spread of infections, as in the coronavirus pandemic, leads to the desire to perform disinfection measures even in the presence of humans. UVC radiation is known for its strong antimicrobial effect, but it is also harmful to humans. Visible light, on the other hand, does not affect humans and laboratory experiments have already demonstrated that intense visible violet and blue light has a reducing effect on bacteria and viruses. This raises the question of whether the development of pathogen-reducing illumination is feasible for everyday applications. For this purpose, a lighting device with white and violet LEDs is set up to illuminate a work surface with 2,400 lux of white light and additionally with up to 2.5 mW/cm2 of violet light (405 nm). Staphylococci are evenly distributed on the work surface and the decrease in staphylococci concentration is observed over a period of 46 hours. In fact, the staphylococci concentration decreases, but with the white illumination, a 90% reduction occurs only after 34 hours; with the additional violet illumination the necessary irradiation time is shortened to approx. 3.5 hours. Increasing the violet component probably increases the disinfection effect, but the color impression moves further away from white and the low disinfection durations of UVC radiation can nevertheless not be achieved, even with very high violet emissions.Item A critical assessment of generative models for synthetic data augmentation on limited pneumonia X-ray data(Universität Ulm, 2023-12-14) Schaudt, Daniel; Späte, Christian; von Schwerin, Reinhold; Reichert, Manfred; von Schwerin, Marianne; Beer, Meinrad; Kloth, Christopher; Mesin, LucaIn medical imaging, deep learning models serve as invaluable tools for expediting diagnoses and aiding specialized medical professionals in making clinical decisions. However, effectively training deep learning models typically necessitates substantial quantities of high-quality data, a resource often lacking in numerous medical imaging scenarios. One way to overcome this deficiency is to artificially generate such images. Therefore, in this comparative study we train five generative models to artificially increase the amount of available data in such a scenario. This synthetic data approach is evaluated on a a downstream classification task, predicting four causes for pneumonia as well as healthy cases on 1082 chest X-ray images. Quantitative and medical assessments show that a Generative Adversarial Network (GAN)-based approach significantly outperforms more recent diffusion-based approaches on this limited dataset with better image quality and pathological plausibility. We show that better image quality surprisingly does not translate to improved classification performance by evaluating five different classification models and varying the amount of additional training data. Class-specific metrics like precision, recall, and F1-score show a substantial improvement by using synthetic images, emphasizing the data rebalancing effect of less frequent classes. However, overall performance does not improve for most models and configurations, except for a DreamBooth approach which shows a +0.52 improvement in overall accuracy. The large variance of performance impact in this study suggests a careful consideration of utilizing generative models for limited data scenarios, especially with an unexpected negative correlation between image quality and downstream classification improvement.Item Über einen möglichen Turing Test auf Bewusstsein(Technische Hochschule Ulm, 2024-09-19) Otte, RalfIn earlier articles it was explained that physical systems with inherent quantum processes are capable of expressing hypercomplex system states. These system states have no real energies, which is why they are not measurable in principle, although they exist physically and can store information. Hypercomplex system states can be aggregated into consciousness in certain systems, such as the human brain. But technical systems could also use their hypercomplex system states. Systems that are able to do so must and will differ significantly in terms of their performance from systems that cannot use such states. This difference in performance can be used to differentiate systems with technical consciousness (so-called "machine consciousness") from systems without "consciousness". Based on this, the article introduces a so-called Turing test for consciousness for technical systems.Item Neuer Knorpel aus dem Reaktor? Entwicklung eines Tissue-Engineering-Bioreaktors für Knorpel des Kopf-Hals-Bereichs(Technische Hochschule Ulm, 2017-09) Wenzel, Ulla; Princz, Sascha; Dettmann, Christian; Goldberg-Bockhorn, Eva; Hasch, Katja; Körber, Ludwig; Lepiarz, Thomas; Munz, Michael; Riepl, Ricarda; Rotter, Nicole; Hessling, MartinKnorpel in Ohren, Nase und Luftröhre bestimmt deren Form und biomechanische Eigenschaften. Kommt es aufgrund von Unfällen oder Erkrankungen zu einem Knorpelverlust, kann dies bei Ohr und Nase zu einer erheblichen funktionellen und psychischen Belastung des Patienten führen. Bei der Luftröhre sind sogar lebensbedrohliche Folgen möglich. Bisherige Behandlungsoptionen bestehen darin, entweder dem Patienten Knorpel an anderer Stelle zu entnehmen oder Knorpelersatzmaterialien einzusetzen. Bei der ersten Variante ist zu beachten, dass nur eine begrenzte Knorpelmenge verfügbar ist und der zusätzliche operative Eingriff zu Komplikationen führen kann. Körperfremde Ersatzmaterialien weisen oft nicht die gewünschten mechanischen Eigenschaften auf und können zu Immunreaktionen führen. Besser wäre es, aus eigenen Zellen des Patienten Knorpel zu züchten und dann zu replantieren. Im BMBF-Projekt BioopTiss wurde an der Hochschule Ulm in Kooperation mit der HNO-Klinik des Universitätsklinikums Ulm die Entwicklung eines dafür geeigneten Bioreaktors begonnen und soll auch zukünftig fortgesetzt werden.Item Towards logistics 4.0: a skill-based OPC UA communication between WMS and the PLC of an automated storage and retrieval system(Technische Hochschule Ulm, 2023-05-15) Lober, Andreas; Ollinger, Lisa; Völker, Sven; Baumgärtel, HartwigIn order to bring intralogistics systems to the same level of interoperability as today’s modern production systems, logistics must take the essential steps towards Industry 4.0. This requires an increasing abstraction level of control logic as an enabler for horizontal and vertical integration. The abstraction will lead to the interconnection of manufacturing and logistics control with the production planning and warehouse management systems (WMS). A main enabler for these communication paths are service-oriented architectures (SoA). OPC UA has established itself as a widely used and already adopted SoA-based communication standard in industry. The paper describes the realization of an OPC UA-based approach for the communication between a WMS and a PLC of an automated storage and retrieval system (ASRS). The conceptual basis of communication design are skills of the ASRS. The work is supported by an architectural design with a subsequent prototypical implementation.Item Flexible operation of electrolysis under local conditions and its impact on the medium voltage grid : a study case of an industrial area in the city of Ulm(Technische Hochschule Ulm, 2023-05-25) Langer, David E.; Idlbi, Basem; Ruf, Holger; Kleiser, GeorgVarious industrial processes need hydrogen (e.g. steel production), which is commonly produced by fossil energy sources and causes a high amount of greenhouse gases. Hydrogen made of sustainably generated electrical power with the Power-to-gas technology (PtG) can substitute fossil-based hydrogen. Distributed generation (DG) of electrical power, e.g. Photovoltaic (PV), in industry areas is increasing. Due to legal requirements, industrial companies must install PV when they expand their premises. Large ground areas and roofs of this buildings result high peak power of feed-in. An increasing shortage of fossil fuels, such as natural gas because of the sanctions in the Ukraine crisis in 2022, also increases the prices and economic risk which in turn makes PV even more attrac tive. The high feed-in peak power of PV force distribution system operators (DSO) to reinforce the electrical grid. A smart grid approach to tackle this challenge is the active balancing of feed-in on a local level, e.g. by PtG. In Germany economic constraints impede so far the utilization of PtG as flexible load. This contribution presents an economic comparison of the costs and the rev enue of electrolysis systems coupled with an electrical grid impact analysis based on simulation results. Furthermore, balancing power at distribution grid level will be considered. Using the data of a real industrial MV grid area near the city of Ulm enable close realistic assumptions. The analysis shows technical results by the grid simulation and economic results. A result of the simulation is detailed data for loading of assets and voltage values for grid operation. The amount and influence of grid reinforcement point quantitative out technical reserve of robust constructed electrical MV grids and set this in context of local PV potential. In comparison to that was with the simula tion demonstrated that flexible load (electrolysis) can be operated to avoiding grid reinforcement. The economic analysis shows the value and allow a quantitative comparison. Thereby was the electrolysis much more profitable than grid rein forcement. Different services and benefits of flexible operated loads were point out in the conclusion, where the outlook discuss gaps in the approach and further analysis that must be taken into consideration.Item Flexible skill-based production systems through novel OPC UA design approaches(Technische Hochschule Ulm, 2023) Lober, Andreas; Lehmann, Joel; Reichwald, Julian; Ollinger, Lisa; Baumgärtel, HartwigIn order to align future forms of production with flexibility, interoperability, and adaptability, the essential steps toward horizontal and vertical integration are indispensable. This paper discusses a conventional and conceptual approach to OPC UA communication and intelligent orchestration of skill-based control logic. The conceptual approach synthesizes this idea with agent structures to provide the possibility to access and combine production capabilities in a reconfigurable manner whilst ensuring the stringent technical requirements on lower automation layers realized by Programmable Logic Controllers (PLCs).Item UV radiation sensitivity of bacteriophage PhiX174 - A potential surrogate for SARS-CoV-2 in terms of radiation inactivation(Technische Hochschule Ulm, 2023-05-05) Weyersberg, Laura; Sommerfeld, Florian; Vatter, Petra; Hessling, MartinTo minimize health risks, surrogates are often employed to reduce experiments with pathogenic microorganisms and the associated health risk. Due to structural similarities between the enveloped RNA-viruses SARS-CoV-2 and Phi6, the latter has been established as a nonpathogenic coronavirus surrogate for many applications. However, large discrepancies in the UV log-reduction doses between SARS-CoV-2 and Phi6 necessitate the search for a better surrogate for UV inactivation applications. A literature study provided the bacteriophage PhiX174 as a potentially more suitable nonpathogenic coronavirus surrogate candidate. In irradiation experiments, the sensitivity of PhiX174 was investigated upon exposure to UV radiation of wavelengths 222 nm (Far-UVC), 254 nm (UVC), 302 nm (broad-band UVB), 311 nm (narrow-band UVB) and 366 nm (UVA) using a plaque assay. The determined log-reduction doses for PhiX174 were 1.3 mJ/cm2 @ 222 nm, 5 mJ/cm2 @ 254 nm, 17.9 mJ/cm2 @ 302 nm, 625 mJ/cm2 @ 311 nm and 42.5 J/cm2 @ 366 nm. The comparison of these results with published log-reduction doses of SARS-CoV-2 in the same spectral region, led to the conclusion that the bacteriophage PhiX174 exhibits larger log-reduction doses than SARS-CoV-2, nevertheless, it is a better UV-surrogate at 222 nm (Far-UVC), 254 nm (UVC) and 302 nm (UVB) than the often applied Phi6.Item Assessing the future hydrogen demand in the mobility sector for the Ulm region in southern Germany(Technische Hochschule Ulm, 2023-09-01) Willich, Caroline; Königsberger, Christopher; Prickler, Pauline; Aydin, Mustafa; Heilmann, Oliver; Schlick, MichaelAs part of a roadmap for the transition to a hydrogen-based infrastructure, the potential hydrogen demand in the mobility as well as the energy sector for the city of Ulm/Neu-Ulm in southern Germany until 2030 was assessed. Possible consumers were identified and their future consumption was estimated. Results showed that the mobile sector can be the driving force for the introduction of a hydrogen-based economy. A demand of about 200 t per year can be expected from commercial transport applications, which will grow to about 1226 t per year in 2028. The sector with the second largest potential is public transportation where a demand of 289 t per year can be expected until 2028, which will grow to a demand of up to 400 t per year until 2030. The demand for trains and garbage trucks were found to remain negligible in comparison until at least 2027.Item Leveraging human expert image annotations to improve pneumonia differentiation through human knowledge distillation(Technische Hochschule Ulm, 2023-06-06) Schaudt, Daniel; Schwerin, Reinhold von; Hafner, Alexander; Riedel, Pascal; Späte, Christian; Reichert, Manfred; Hinteregger, Andreas; Beer, Meinrad; Kloth, ChristopherIn medical imaging, deep learning models can be a critical tool to shorten time-to-diagnosis and support specialized medical staff in clinical decision making. The successful training of deep learning models usually requires large amounts of quality data, which are often not available in many medical imaging tasks. In this work we train a deep learning model on university hospital chest X-ray data, containing 1082 images. The data was reviewed, differentiated into 4 causes for pneumonia, and annotated by an expert radiologist. To successfully train a model on this small amount of complex image data, we propose a special knowledge distillation process, which we call Human Knowledge Distillation. This process enables deep learning models to utilize annotated regions in the images during the training process. This form of guidance by a human expert improves model convergence and performance. We evaluate the proposed process on our study data for multiple types of models, all of which show improved results. The best model of this study, called PneuKnowNet, shows an improvement of + 2.3% points in overall accuracy compared to a baseline model and also leads to more meaningful decision regions. Utilizing this implicit data quality-quantity trade-off can be a promising approach for many scarce data domains beyond medical imaging.Item Simulation der Betriebsstrategie eines hybriden Batterie-Brennstoffzellenfahrzeuges(Technische Hochschule Ulm, 2024-07-03) Grabow, Andreas; Heilmann, Oliver; Schlick, Michael; Dettmann, ChristianDiese Bachelorarbeit untersucht die Erstellung und den Vergleich von zwei Simulationsmodellen eines Wasserstofffahrzeuges. Dabei wird eine mögliche Betriebsstrategie erstellt. Die Modelle basieren größtenteils auf einer physikalischen Modellierung. Ziel ist es, eine mögliche Betriebss trategie der Modelle zu erstellen und statistisch zu vergleichen. Die statistische Untersuchung einiger Simulationsergebnisse belegen dabei die Gleichheit der Ergebnisse der beiden Modelle. Unterschiede der Modellierung werden aufgezeigt. Die Arbeit trägt dazu bei, eine Validierung der Simulationsmodelle anhand eines realen Fahrzeugs vorzubereiten, mit dem wiederum virtuelle Testfahrten durchgeführt werden können.