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Item type:Publication, Access status: with files , Methods and tools for the quantification and improvement of measurement uncertainty in light field measurement for projection systemsProjection-type optical systems, such as Head-Up Displays (HUDs), Virtual Reality (VR), and Augmented Reality (AR), provide immersive experiences in virtual worlds or ergonomically present supplementary information in real-world contexts. These systems play a crucial role in modifying the light emitted by imagers to generate virtual images in front of the user, greatly enhancing user engagement and interaction. In VR and AR applications, the immersive quality and usability of the system depend critically on the fidelity and stability of these virtual images. Central to these experiences is the concept of a virtual image, an image plane created in a space without physical representation. A virtual image typically arises when projection systems modify and direct light to form the perception of an object or scene at a specific location in space. However, a significant challenge in such optical systems is image distortion, which occurs as light passes through complex optical paths. A wide range of optical technologies including holograms, Fresnel lenses, traditional lenses, and mirror optics are employed to construct these systems. As images propagate through these elements, distortions can cause elements of the virtual image to be projected at varying distances. This results in visual inconsistencies that can disrupt the immersive experience. While the human visual system can often compensate for these distortions unconsciously, evidence shows that persistent image distortion may lead to discomfort, motion sickness, and headaches. These effects hinder long-term ergonomic usage and holistic user experience. Image distortion in these systems is inherently three-dimensional due to the complex arrangement of optical components. This 3D distortion is a major challenge for optical design, impacting device quality and user satisfaction, especially for AR applications. Accurately measuring and characterizing these distortions requires advanced methods. To address this, a light field measurement system has been developed, with the ability to reconstruct images and analyze spatial and angular light information far beyond the limits of human perception. This thesis addresses the sources and impacts of three-dimensional distortion in projection-type optical systems. It presents a comprehensive measurement methodology for evaluating image quality. By tackling these challenges and optimizing projection systems, this work contributes to improved user experience and long-term usability in next-generation immersive display technologies.Publicationtype: Doctoral Thesis60 22 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Quantifying and optimizing the complexity: a comprehensive method to modeling and simulation in electrical DC systems : a maritime and mechatronic case study(2026); The development of maritime electrical energy systems is a key technology for greener shipping. In this work, a comprehensive methodology for creating models and simulations of electrical DC power systems to an appropriate level of accuracy is developed. The proposed methodology aims to optimize the simulation and model complexity a priori as to avoid an overly costly and excessively accurate simulation.Publicationtype: Doctoral Thesis81 38 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Multi-sensor system design for in-situ ocean surface monitoring using wave-energy-harvesting(2023); This thesis proposes a design approach for a modular multi-sensor monitoring system to improve accessibility to in-situ observations of the sea surface. The design includes a flexible measurement module for hardware agnostic sensor extensions, an embedded conductivity and temperature sensor for cost-effective salinity measurements, and a wave energy harvester for long-term deployments. Model-based design methods are used to derive fundamental design principles and allow multi-physics optimization. The low-cost system enables large-scale deployment of in-situ measurements and may pave the way for the next generation of in-situ sea surface monitoring.Publicationtype: Doctoral Thesis185 137 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Entwicklung einer Methodik zur systemischen Optimierung elektrischer Antriebseinheiten durch weiterentwickelte Kühlkonzepte und antriebsinternes Thermomanagement(2023); The mobility sector is undergoing a radical change towards electromobility. This leads to increasing demands on the development of new electric powertrains of future electric vehicles. The electric drive unit should be cost-effective, compact, durable and be as effcient as possible in all driving scenarios under different environmental conditions. With increasing complexity and component integration of the drive units, the influence of the thermal behavior of the components (electric motor, power electronics and transmission) and their mutual coupling increases. Some of the components have strong divergent, optimal operating temperature ranges, which leads to opposite requirements for the drive unit cooling system. The cooling system and associated drive unit internal thermal management represent the interfaces between the components and offer additional possibilities to increase the effciency of the system. In order to develop the optimal overall concept of an electric drive unit for a vehicle platform, a systemic consideration of costs, effciency, mass and lifetime under compliance with installation space and limit temperatures for use in various vehicles is necessary. Within the scope of this thesis, a methodology for the systemic evaluation of cooling concepts and thermal management measures of electric drive units is developed. The components the tool chain (thermal component models, cost models and transmission design models) as well as the thermal drive model are validated on the basis of various different measurements. The presented tool chain enables the evaluation and optimization of cooling concepts for electric drive units under consideration of different drive cycles. In order to assess the overall system under the above aspects a cost equivalent number approach based on vehicle-speci c properties is used. Furthermore, additional drive unit internal thermal management measures are evaluated and optimized in order to reduce energy consumption and at the same time provide the best drive unit solutions. The application possibilities of the tool chain are shown based on various parameter studies and optimizations.Publicationtype: Doctoral Thesis327 198 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Development and implementation of a manufacturing concept for a low-cost inductive conductivity sensor for maritime applications(2021-12-09); In this work, a conductivity sensor based on a dual transformer is developed for use on self-sufficient buoys. The design and optimization of the physical sensor are based on simulation models in MATLAB. Based on the design of the double transformer and a given microcontroller, circuits for excitation and measurement amplification are designed. The circuits, microcontroller, and transformer are combined on a printed circuit board to form an embedded sensor. Based on the microcontroller and the cell constant required in conductivity measurement, software concepts are presented. The cell constant is determined through a series of experiments on the potted dual transformer.Publicationtype: Master Thesis206 1648