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In this thesis, a contribution to explainable artificial intelligence is made. More specifically, the aspect of artificial intelligence which focusses on recreating the human perception is tackled from a previously neglected direction. A variant of human perception is building a mental model of the extents of semantic objects which appear in the field of view. If this task is performed by an algorithm, it is termed image segmentation. Recent methods in this area are mostly trained in a superv...
Modern automotive systems integrate a variety of electrical and electronic components. To estimate the radiated emissions, the standard CISPR 25 describes the absorber-lined shielded enclosure (ALSE) method, which is the most important standardized field measurement method. However, it suffers from the need for a large anechoic chamber. To reduce costs and more conveniently integrate radiated emission investigations into the product design cycle, alternative methods that predict emissions wit...
Die Datenvernetzung innerhalb des Fahrzeuges hat Einfluss auf das Gewicht, das Volumen und die Komplexität des Fahrzeugkabelbaums. Mit den traditionellen Kfz-Bussystemen und der großen Vielfalt an Funktionen, die in Zukunft noch zunehmen wird, lässt sich ein Optimum hinsichtlich dieser Kriterien nur schwer erreichen. Eine mögliche Lösung könnte die Datenübertragung über das Kfz-Energiebordnetz darstellen. Die sogenannte Powerline Communication (PLC) ist eine Technologie, die die vorhandenen E...
The increasing use of electric vehicles (EV) brings up the need to invest in the charg- ing infrastructure and extend the number of charging sites and stations. Especially the integration of fast charging sites increases the convenience for the user. The growing utilization of charging sites is also a chance to learn about charging be- haviour and future needs. In this thesis, usage data of a charging site in Norway is processed by a self-developed modelling tool, to create charging prof...
Die vorgestellte integrierte Fahrdynamikregelung bestimmt aus einer Bewegungsvorgabe auf Beschleunigungsebene, Messgrößen vom Fahrzeug und momentanen Umweltparametern Stellgrößen, die das Fahrzeug die Bewegungsanforderung möglichst exakt umsetzen lassen. Die Stellgrößen werden unter gleichzeitiger Berücksichtigung jeder Komponente der Bewegungsvorgabe und der Gesamtheit der verfügbaren Stellmöglichkeiten ermittelt. Verbleiben nach Umsetzen der Vorgabe Freiheitsgrade in den Stellgrößen, so wer...
Ester-based insulation fluids are being increasingly used in high-voltage insulation systems. The reasons are the advantages in the area of ecological compatibility and resource-saving provision. The intention to use ester-based insulation fluids in high voltage direct current (HVDC) equipment is new. The major challenge in designing the HVDC insulation system is, that the systems do not only experience an alternating voltage, but also a direct voltage Offset. This presents a challenge to pre...
We measured methane (CH4) and stable carbon isotope of methane (δ13C-CH4) concentrations in ambient air and within a red wood-ant (RWA; Formica polyctena) nest in the Neuwied Basin (Germany) using high-resolution in-situ sampling to detect microbial, thermogenic, and abiotic fault-related micro-seepage of CH4. Methane degassing from RWA nests was not synchronized with earth tides, nor was it influenced by micro-earthquake degassing or concomitantly measured RWA activity. Two δ13C-CH4 signatur...
For the design of the next generation of microelectronic packages, thermal management is one of the key aspects and must be met by the development of polymers with enhanced thermal conductivity. While all polymer classes show a very low thermal conductivity, this shortcoming can be compensated for by the addition of fillers, yielding polymer-based composite materials with high thermal conductivity. The inorganic fillers, however, are often available only in submicron- and micron-scaled dimens...
In a world where service robots are increasingly becoming an inherent part of our lives, it has become essential to provide robots with superior perception capabilities and acute semantic knowledge of the environment. In recent years, the computer vision field has advanced immensely, providing rich information at a fraction of the cost. It has thereby become an essential part of many autonomous systems and the sensor of choice while tackling the most challenging perception problems. Neverth...
Die Flexibilität der elektrischen Leistung ist eine wesentliche Eigenschaft elektrischer Energiesysteme, die zum Ausgleich absehbarer oder unvorhergesehener Schwankungen von Stromerzeugung und -verbrauch benötigt wird. Durch den steigenden Anteil Erneuerbarer Energien an der Stromerzeugung entsteht somit auch ein erhöhter Bedarf an betrieblicher Flexibilität. Zeitgleich sorgt der Rückbau konventioneller Kraftwerke zu einem verminderten Flexibilitätsangebot, wodurch zukünftig die Erschließung ...
Geochemical tracers of crustal fluids (CO2, He, Rn) provide a useful tool for the identification of buried fault structures. We acquired geochemical data during 7-months of continual sampling to identify causal processes underlying correlations between ambient air and degassing patterns of three gases (CO2, He, Rn) in a nest of red wood ants (Formica polyctena; “RWA”) and the soil at Goloring in the Neuwied Basin, a part of the East Eifel Volcanic Field (EEVF). We explored whether temporal re...
We present a comprehensive study on how to design and fabricate low loss electro-optic phase shifters based on an electro-optic polymer and the silicon nitride and silicon oxynitride waveguide material systems. The loss mechanisms of phase shifters with an electro-optic (EO) polymer cladding are analyzed in detail and design solutions to achieve lowest losses are presented. In order to verify the low loss design a proof of concept prototype phase shifter was fabricated, which exhibits an atte...
Electro-static discharge (ESD) event can cause upset or permanent damage of integrated circuits (IC) and electrical systems. The risk of ESD fails needs to be mitigated or prevented. ESD robustness of IC products and electrical systems is specified, verified and qualified according to respective ESD standards. For high-voltage IC products based on smart power semiconductor technologies for industrial, power and automotive applications, design of effective and cost-efficient ESD protection is ...
This thesis deals with the development and analysis of novel time-optimal model predictive control concepts for nonlinear systems. Common realizations of model predictive controllers apply direct transcription methods to first discretize and then optimize the subordinate optimal control problems. The key idea of the proposed concepts is to introduce discretization grids in which the underlying discretization is explicitly treated as temporally variable during optimization. A single optimizati...
All of the objects in the real world are envisioned to be connected and/or represented, through an infrastructure layer, in the virtual world of the Internet, becoming Things with status information. Services are then using the available data from this Internet-of-Things (IoT) for various social and economical benefits which explain its extreme broad usage in very heterogeneous fields. Domain administrations of diverse areas of application developed and deployed their own IoT systems and serv...
Silicon oxycarbide deposited by plasma enhanced chemical vapor deposition is investigated regarding its application as a material for optical waveguides. The dependence of the infrared absorption, the refractive index, and the surface roughness on the precursor gas flow ratios is studied by Fourier transform infrared spectroscopy, ellipsometry, and atomic force microscopy, respectively. Results show that the refractive index can be tuned over a significant wider range compared to silicon oxyn...
Fast 10 Jahre nach Veröffentlichung des Nationalen Entwicklungsplan Elektromobilität liegt der Bestand an batterieelektrischen Elektrofahrzeugen und Plug-In Hybriden bei ca. 100.000 und damit bei 10 % des Ziels der Bundesregierung für das Jahr 2020. Der gewerbliche Verkehrssektor mit insgesamt ca. 6 Mio. Fahrzeugen an Pkw und leichten Nutzfahrzeugen verfügt über Voraussetzungen ein Eintrittssegment darzustellen und die Marktintegration stärker voranzutreiben, und begründet dadurch den Fokus d...
We present a geochemical dataset acquired during continual sampling over 7 months (bi-weekly) and 4 weeks (every 8 h) in the Neuwied Basin, a part of the East Eifel Volcanic Field (EEVF, Germany). We used a combination of geochemical, geophysical, and statistical methods to describe and identify potential causal processes underlying the correlations of degassing patterns of CO2, He, Rn, and tectonic processes in three investigated mineral springs (Nette, Kärlich and Kobern). We provide for th...
Energy conversion and distribution of heat and electricity is characterized by long planning horizons, investment periods and depreciation times, and it is thus difficult to plan and tell the technology that optimally fits for decades. Uncertainties include future energy prices, applicable subsidies, regulation, and even the evolution of market designs. To achieve higher adaptability to arbitrary transition paths, a technical concept based on integrated energy systems is envisioned and descri...