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The industry of safety-critical and dependable embedded systems calls for even cheaper, high performance platforms that allow flexibility and an efficient verification of safety and real-time requirements. In this sense, flexibility denotes the ability to (online) adapt a system to changes (e.g. changing environment, application dynamics, errors) and the reuse-ability for different use cases. To cope with the increasing complexity of interconnected functions and to reduce the cost and power consumption of the system, multicore systems are used to efficiently integrate different processing units in the same chip. Networks-on-chip (NoCs), as a modular interconnect, are used as a promising solution for such multiprocessor systems on chip (MPSoCs), due to their scalability and performance. Hence, future NoC designs must face the aforementioned challenges.For safety-critical systems, a major goal is the avoidance of hazards. For this, safety-critical systems are qualified or even certified to prove the correctness of the functioning under all possible cases. A predictable behavior of the NoC can help to ease the qualification process (e.g. formal analysis) of the system. To achieve the required predictability, designers have two classes of solutions: isolation (quality of service (QoS) mechanisms) and (formal) analysis. For mixed-criticality systems, isolation and analysis approaches must be combined to efficiently achieve the desired predictability. Isolation techniques are used to bound interference between different application classes. And analysis can then be applied verifying the real-time applications and sufficient isolation properties.Traditional NoC analysis and architecture concepts tackle only a subpart of the challenges-they focus on either performance or predictability. Existing, predictable NoCs are deemed too expensive and inflexible to host a variety of applications with opposing constraints. And state-of-the-art analyses neglect certain platform properties (e.g. they assume sufficient buffer sizes to avoid backpressure) to verify the behaviour. Together this leads to a high over-provisioning of the hardware resources as well as adverse impacts on system performance (especially for the non safety-critical applications), and on the flexibility of the system.In this work we tackle these challenges and develop a predictable and runtime-adaptable NoC architecture that efficiently integrates mixed-critical applications with opposing constraints. Additionally, we present a modeling and analysis framework for NoCs that accounts for backpressure (i.e. full buffers in network routers delaying the progress of network packets). This framework enables to evaluate the performance and reliability early at design time. Hence, the designer can assess multiple design decisions and trade-offs (such as area, voltage, reliability, performance) by using abstract models and formal approaches.

Successful miniaturization of complex electro-optic devices is a prerequisite for bringing quantum optical sensors to work outside optical labs in a real-world application scenario. Monolithic, i.e. chip-scale integration, holds the promise of achieving the highest level of compactness, robustness, and reliability at the lowest production cost possible.This work focuses on modelling, simulation, design, manufacturing, and testing of functional building blocks for photonic integrated circuits. GaAs-based waveguides, NxM multi-mode interference couplers, and electro-optic phase modulators were developed for applications of rubidium precision spectroscopy at 780 nm for the first time. As an example for photonic integrated circuits a monolithic amplitude modulator based on a Mach-Zehnder-interferometer was demonstrated. Further, GaAs-based phase modulators were developed for applications at 1064 nm. For operation at 780 nm single-mode waveguides with an exceptionally small loss of 1.2 dB/cm and phase modulators with an efficiency as large as 16 deg/(Vxmm) were demonstrated.This work additionally advances the experimental methods available to investigate the electro-optic properties of phase modulators: a novel method based on the I&Q-demodulation of time domain modulation signals derived with a heterodyne interferometer does not only provide access to the phase but also to the (residual) amplitude modulation and allows to separate linear from quadratic phase modulation effects. This provides novel experimental insights into the physical effects governing phase modulation. In fact, it is shown that the current understanding according to which carrier-density related effects contribute solely to the linearly of phase modulation is questionable.

In search of an alternative for chemicals and energy from fossil fuels, lignin pyrolysis is experimentally investigated in a circulating fluidized bed. Deviation in pyrolysis behavior of a softwood Kraft lignin and a wheat straw hydrolysis lignin is analyzed by means of char morphology as well as overall yield and composition determination for gas, oil, and char. The influence of catalytically active mineral matter in lignin on the product distribution is investigated. Progressively, the fluidized bed pyrolysis process is modeled semi-empirically considering fluid dynamics, feedstock composition, micro-particle pyrolysis reactions and mass balances. The lignin secondary reaction kinetics from oil-to-gas are obtained from the Kraft lignin experimental data and a pyrolysis plant with integrated char and permanent gas combustion is modeled with a flowsheeting tool.

Egon Petri, one of the most admired musicians of his generation, brought the sensibilities of the nineteeth century to his students in the mid-twentieth century. In his youth, his parents' home hosted the likes of Brahms, Tchaikovsky, and Clara Schumann, and he studied with Ferruccio Busoni and other great musicians of the prewar and interwar periods. As a prolific and magisterial pianist, he performed prodigious programs throughout Europe and Russia, both solo recitals and concerts with the great orchestral conductors of the time, before settling in Oakland, California in the United States. With ongoing interest in Petri's life, artistry, and teaching intensified by a re-release of his 1929-1951 recordings, Alfred Kanwischer returned to transcripts of interviews he had conducted with Petri in the period 1960-1962 to create this engaging narrative, replete with treasured memories and extensive direct quotations revealing Petri's charm, humor, and wisdom.The narrative is divided into chapters focusing on Petri's youth, influences, performance artistry, and teaching, with engaging interludes on conductors and "dream pianos." Fans of classical music will find the world revealed in this book fascinating, while pianists and piano teachers will find it useful and inspiring.A facsmile of a booklet detailing Petri's concert repertoire during the period 1892-1929 is also included.

Two novel nanoarchitectures - including the highly branched spikecube exemplified by ß-SnWO4 and the biomimetic nanopeapod manifested in Au@Nb@HxK1-xNbO3 - were put forward for the first time in this dissertation, particularly aiming at enriching the library of pattern designs for sunlight-driven photo(electro)chemical applications. Specifically, ß-SnWO4 spikecubes were entitled on the basis of the peculiar morphology, wherein bundles of nanopillars were self-aligned with quasi-periodicity onto each sharp face of hexahedral cube cores. Moreover, this geometric engineering was particularly carried out on a Scheelite-type (ABO4) ß-SnWO4 crystal with a visible-light-active band gap of 2.91 eV and subtle conduction and valence band positions, endowing the photoexcited electron-hole pairs on ß-SnWO4 with strong reducing and oxidizing power, respectively. Consequently, an outstanding photocatalytic activity in degrading organic dyes was observed for the ß-SnWO4 spikecube with an enhancement more than 150% in comparison with a benchmark visible-light-active WO3 photocatalyst. By contrast, the design of Au@Nb@HxK1-xNbO3 emulates the growth pattern of a natural plant - a peapod -, wherein sub-10 nm core-shell Au@Nb plasmonic bimetallics as the particulate peas seeded discretely inside the unidirectional cavity of the tubular HxK1-xNbO3 semiconductor as the pod. The biomimicry of this configuration endows the Au@Nb@HxK1-xNbO3 nanopeapods with strong light harvesting abilities, wherein the HxK1-xNbO3 nanopod and the Au@Nb nanopeas absorb ultraviolet and visible light via interband transition and surface plasmon resonance, respectively. More importantly, the strong near-field plasmon-plasmon coupling between neighboured Au@Nb nanoparticles allows the Au@Nb@HxK1-xNbO3 nanopeapod absorbing near-infrared light. Last but not least, dye photodegradation and water photoelectrolysis as proofs-of-concept manifested the full-spectrum utilization of diffusive solar energy by the Au@Nb@HxK1-xNbO3 nanopeapod for environmental remediation and fuel generation, respectively.

Low Bond number open capillary channel flows have been shown to exhibit collapsing free surfaces when a critical flow rate is exceeded, a phenomenon that is referred to as choking. As shown in this work, the critical flow rate can be pre-determined with sufficient accuracy for the presented channel geometry when certain boundary conditions are known a priori. The presented model that describes the flow rate limitation of stable liquid flow through the open channel is examined and compared to numerical simulations and experimental studies. In addition, the characteristics of the supercritical domain, in which bubbles are ingested passively into the flow in the channel, are described and a new model for bubble formation via choking is proposed.

BeschreibungDie Dissertation "Risk Assessment of Covered Bonds in the International Secondary Market - An Empirical Analysis" beschäftigt sich mit der Risikobewertung von Covered Bonds im internationalen Sekundärmarkt. Covered Bonds sind verzinsliche Wertpapiere, die von Finanzinstituten emittiert werden und durch Vermögenswerte besichert sind, welche in einem sogenannten Cover Pool zusammengefasst werden. In der großen Mehrheit der Fälle handelt es sich bei diesen Vermögensgegenständen entweder um Hypothekendarlehen oder um Kredite an öffentliche Stellen, wie z. B. Staaten oder sonstige Gebietskörperschaften. Die durch diese Arten von Vermögensgegenständen besicherten Covered Bonds werden dementsprechend als Hypotheken-Covered-Bonds bzw. öffentliche Covered Bonds bezeichnet. Während Covered Bonds in der Vergangenheit häufig generell als nahezu ausfallrisikofrei angesehen wurden, hat sich diese Ansicht bedingt durch die Finanzkrise sowie die sich anschließende Staatsschuldenkrise geändert. Vor diesem Hintergrund wird in dieser Arbeit im Rahmen von empirischen Analysen sowohl für öffentliche als auch für Hypotheken-Covered-Bonds untersucht, welche Faktoren die Höhe der Risikoprämien beeinflussen und es werden diesbezügliche Unterschiede zwischen den beiden Covered-Bond-Arten aufgezeigt.

Coal is a rock composed of organic and inorganic materials, which contains 50% or more than 75% organic material (Fig. 1). The organic matter mostly consists of carbon ©, but is also comprised of hydrogen (H), oxygen (O), sulphur (S) and nitrogen (N). Besides organic matter, coal contains some inorganic compounds (minerals) and water (H2O). Naturally, coal is formed from vegetation that has been consolidated between other rock strata and altered by the combined effects of pressure and heat over millions of years to ultimately form coal seams (World Coal Institute, 200

Der deutsche Strommarkt unterliegt durch den zunehmenden Anteil der Stromerzeugung aus Erneuerbaren Energien einem fundamentalen Wandel. Von zentraler Bedeutung ist der Merit-Order-Effekt, der die Verdrängung konventioneller Stromerzeugung und damit einhergehende Preisminderungseffekte beschreibt. In der vorliegenden Arbeit werden in diesem Zusammenhang grundlegende Preiszusammenhänge des Großhandelsmarktes unter Berücksichtigung der Stromerzeugung aus Wind und Photovoltaik analysiert. Dies erfolgt zum einen über Paneldaten-Modelle, zum anderen werden über Zeitreihenmodelle Kurzfristprognosen erstellt. Dabei werden die folgenden Kernfragen der Arbeit thematisiert: Was ist der aktuelle Stand der wissenschaftlichen Forschung im Bereich Zeitreihenanalyse auf Großhandelsmärkten für Strom? Welche Zeitreihenmodelle weisen die beste Prognosequalität auf? Und: Welche Preiseffekte hat die Stromerzeugung aus Erneuerbaren Energien? Die Beantwortung erfolgt über umfangreiche Literaturanalysen und empirische Studien.

In recent years, Silicon Photomultipliers (SiPMs) developed into mature photon detectors which are chosen in a wide field of applications. However, the dark count rate (DCR) of SiPMs sets strong limitations to such detector systems. This quantity describes the rate at which pulses are generated in the absence of light (dark pulses) and deteriorate the photon counting performance of SiPMs.In the course of the presented research, two innovative characterization methods were developed for the identification and evaluation of the physical effects which underlie the generation of dark pulses in SiPMs.The first method is based on the temperature dependence of the DCR. It allows for the extraction of different contributions to the dark count rate, which (a) depend on the applied voltage, (b) depend on the applied overvoltage and © are quasi-independent of the electric field. The second method is based on the detection and mapping of the light intensity which is emitted by the effect of hot carrier luminescence during the avalanche breakdowns of SiPM micro-cells. This method enables a sub-micro-cell, 2D spatially resolved measurement of the dark count rate within the plane of the active area. In particular, the individual contributions of implantation and radiation induced defects to the DCR were evaluated via this method.The acquired knowledge was used to successfully suppress the dark count rate of KETEK SiPMs down to a level of 40 kHz/mm².

BeschreibungGases have to be specifically mixed with a continuous liquid phase to perform a reaction with high yield and selectivity. The time scales of mixing are determined by the transport processes in the boundary layer close to the phase boundary and by bubble swarm turbulence. For clarification of the local mass transfer in bubbly flows, an experimental setup is developed and successfully used to investigate single rectilinear (spherical), helical (ellipsoid) and irregular rising bubbles with and without chemical reaction. Therefore, the time resolved scanning laser induced fluorescence technique is further developed and applied for the first time to bubbly flows to allow new insights in the mass transfer processes.

As digitalization has caused major changes within various traditional industries, firms are forced to explore new technological paths and access knowledge beyond their boundaries. This dissertation focuses on knowledge provided by startups. Besides introducing search approaches and successful search strategies to identify startups, this work also provides insights into how corporations may become attractive partners for startups. In addition, the quality of startup ideas is compared with ideas originating from established suppliers. Finally, this dissertation examines the implications of engaging with startups

The natural behavior of pigs is adapted to very complex environments and is characterized by a high proportion of exploratory behaviour. In modern, intensive husbandry systems, the behaviour pigs would show in natural environments cannot be expressed to the degree that is necessary for the animals to maintain a positive emotional state. Health and behaviour problems arise in intensive pig husbandry, leading to stress and negative emotional states in the animals. This animal welfare problem fuels growing concerns of the public. As negative emotional states, such as stress, are more intensely expressed and potentially life threatening, they are easier to study. The expression of positive emotion, even though it is expressed more subtle, is no less important. This study was therefore conducted with the objective to identify, elicit and measure behavioural and physiological indicators of positive emotion in pigs. With the ability to facilitate a positive emotional state, the welfare of pigs kept in intensive livestock production systems can be greatly improved.

Thermal barrier coatings (TBCs) are ceramic coating systems developed to reduce the heat transfer from a hot medium to the coated parts. This technology can be used in automotive exhaust systems to reduce the heat transfer from the exhaust gases to the metal pipes. As a result, catalytic converters can reach the ideal temperature for the conversion of gases more quickly, reducing emissions. In order to be effective, coatings must be applied to the inside of pipes. However, conventional techniques for the preparation of ceramic coatings are not suitable for the deposition of coatings inside of long pipes with small diameter, or are too expensive. In this work, a TBC system was developed using the polymer-derived ceramics (PDC) technique. In this method, ceramic coatings are obtained by the thermal conversion of preceramic polymers into ceramics, after deposition of the coatings by simple lacquer techniques. Fillers are used to tailor the microstructure and the properties of the coatings. This book contains a review of the literature on PDC coatings, the procedures for the preparation of the TBCs, as well as their properties.

In the present work, both in silico and in vivo methods for flux analysis in plants were successfully developed and applied for enhanced understanding of plant physiology. Taken together, the in silico metabolic simulations provide detailed molecular insights into plant functioning, particularly by linking in vivo with in silico data. The knowledge gained from such a systems-biological approach, together with the proposed high potential of plants as biotechnological production platforms, especially for compounds requiring much redox power, will help to establish plants as biotechnological factories.For the first time, the in vivo metabolism of an agriculturally relevant crop, O. sativa, was investigated, through non-stationary 13C-metabolic flux analysis. This allowed elucidation of the in vivo intracellular carbon partitioning in rice plants and of the plants' necessity for futile cycling of resources, thus, contributing significantly to our current knowledge on plant metabolism. In addition, the effect of imazapyr, an industrially relevant herbicide, on rice metabolism was inspected using the newly established workflow. This first real-life case-study provides a valuable proof-of-principle and enabled a deeper understanding of the immediate metabolic effects of the treatment. This method can now be adopted to other crops, cell lines and stress inducers, such as abiotic stresses, herbicides and fungicides, and therefore, has great potential in green biotechnology.