Informationen aus dem Lehrstuhl für Fertigungstechnik und Betriebsorganisation

Der vorliegende Beitrag basiert auf einer Umfrage von 2019, die in kleinen und mittleren Unternehmen (KMU) in Rheinland-Pfalz durchgeführt wurde. Seit Jahren ist in den Medien, der Politik und der Wirtschaft verstärkt von Digitalisierung und Industrie 4.0 die Rede. Diese Entwicklung stellt Unternehmen aller Größen und Branchen vor Herausforderungen, jedoch liegt der Fokus hauptsächlich auf großen Unternehmen. Ziel der in diesem Beitrag vorgestellten Studie ist es, herauszufinden wie KMU in Rheinland-Pfalz den Herausforderungen und Chancen der Digitalisierung begegnen, welche Rolle das Controlling bei der digitalen Transformation spielt und welche Implikationen sich daraus für das Controlling ergeben.

Ziel dieser Arbeit ist die Entwicklung einer optimierungsbasierten Betriebsstrategie von Plug-In-Hybridfahrzeugen (PHEV), welche basierend auf Vorausschauinformationen die Freiheitsgrade Lastpunktverschiebung und Motor-An/Aus-Entscheidung kraftstoffoptimal einstellt. Der Hauptfokus der Arbeit liegt dabei auf der Entwicklung einer echtzeitfähigen Strategie für Serienfahrzeuge. Hierfür wird ein neuartiger Ansatz auf Basis des Minimumprinzips nach Pontryagin (PMP) vorgestellt, durch welchen die Freiheitsgrade des PHEV kraftstoffoptimal eingestellt werden können. Dabei werden Informationen über die vorausliegende Strecke effizient berücksichtigt. Die Qualität der in der Realität verfügbaren Vorausschaudaten stellt jedoch eine besondere Herausforderung dar, da dadurch zwei in der Praxis besonders relevante Aspekte auftreten: 1) Bei der Verwendung von PMP können durch das besonders starke Auftreten sogenannter Singularitäten die Randbedingungen des Optimalsteuerungsproblems nicht exakt eingehalten werden. Um dieses Problem zu lösen, wurde in dieser Arbeit eine neuartige, PMP basierte Methodik entwickelt. 2) Die für die Optimierung zur Verfügung stehenden Informationen sind zwangsweise unsicher, und das reale Fahrzeugverhalten weicht von dem der Navi-Vorausschau ab. Um mit dieser Unsicherheit umgehen zu können, wurde in dieser Arbeit eine Feedback-Struktur entwickelt, welche eine Anpassung der Strategie auf ein abweichendes Fahrzeugverhalten ermöglicht. Des Weiteren wurde eine Verallgemeinerung der vorgestellten PMP-Methodik entwickelt, wodurch eine Integration von Motorstartkosten und externen Anforderungen an die Motor-An/Aus-Entscheidung ermöglicht werden kann. Zu diesem Zweck wurde eine Kombination von Dynamischer Programmierung und PMP betrachtet. Die entwickelten Strategien wurden sowohl in der Simulation wie auch auf einem Prüfstand analysiert und validiert. Abschließend wurde hierfür ein Vergleich mit regelbasierten Betriebsstrategien vorgestellt. Dabei konnte ein deutlicher Verbrauchsvorteil durch die Verwendung der entwickelten, optimierungsbasierten Betriebsstrategie ausgewiesen werden.

Risk management is an indispensable component of the financial system. In this context, capital requirements are built by financial institutions to avoid future bankruptcy. Their calculation is based on a specific kind of maps, so-called risk measures. There exist several forms and definitions of them. Multi-asset risk measures are the starting point of this dissertation. They determine the capital requirements as the minimal amount of money invested into multiple eligible assets to secure future payoffs. The dissertation consists of three main contributions: First, multi-asset risk measures are used to calculate pricing bounds for European type options. Second, multi-asset risk measures are combined with recently proposed intrinsic risk measures to obtain a new kind of a risk measure which we call a multi-asset intrinsic (MAI) risk measure. Third, the preferences of an agent are included in the calculation of the capital requirements. This leads to another new risk measure which we call a scalarized utility-based multi-asset (SUBMA) risk measure. In the introductory chapter, we recall the definition and properties of multi-asset risk measures. Then, each of the aforementioned contributions covers a separate chapter. In the following, the content of these three chapters is explained in more detail: Risk measures can be used to calculate pricing bounds for financial derivatives. In Chapter 2, we deal with the pricing of European options in an incomplete financial market model. We use the common risk measures Value-at-Risk and Expected Shortfall to define good deals on a financial market with log-normally distributed rates of return. We show that the pricing bounds obtained from Value-at-Risk may have a non-smooth behavior under parameter changes. Additionally, we find situations in which the seller's bound for a call option is smaller than the buyer's bound. We identify the missing convexity of the Value-at-Risk as main reason for this behavior. Due to the strong connection between the obtained pricing bounds and the theory of risk measures, we further obtain new insights in the finiteness and the continuity of multi-asset risk measures. In Chapter 3, we construct the MAI risk measure. Therefore, recall that a multi-asset risk measure describes the minimal external capital that has to be raised into multiple eligible assets to make a future financial position acceptable, i.e., that it passes a capital adequacy test. Recently, the alternative methodology of intrinsic risk measures was introduced in the literature. These ask for the minimal proportion of the financial position that has to be reallocated to pass the capital adequacy test, i.e., only internal capital is used. We combine these two concepts and call this new type of risk measure an MAI risk measure. It allows to secure the financial position by external capital as well as reallocating parts of the portfolio as an internal rebooking. We investigate several properties to demonstrate similarities and differences to the two aforementioned classical types of risk measures. We find out that diversification reduces the capital requirement only in special situations depending on the financial positions. With the help of Sion's minimax theorem we also prove a dual representation for MAI risk measures. Finally, we determine capital requirements in a model motivated by the Solvency II methodology. In the final Chapter 4, we construct the SUBMA risk measure. In doing so, we consider the situation in which a financial institution has to satisfy a capital adequacy test, e.g., by the Basel Accords for banks or by Solvency II for insurers. If the financial situation of this institution is tight, then it can happen that no reallocation of the initial endowment would pass the capital adequacy test. The classical portfolio optimization approach breaks down and a capital increase is needed. We introduce the SUBMA risk measure which optimizes the hedging costs and the expected utility of the institution simultaneously subject to the capital adequacy test. We find out that the SUBMA risk measure is coherent if the utility function has constant relative risk aversion and the capital adequacy test leads to a coherent acceptance set. In a one-period financial market model we present a sufficient condition for the SUBMA risk measure to be finite-valued and continuous. Finally, we calculate the SUBMA risk measure in a continuous-time financial market model for two benchmark capital adequacy tests.

By mapping the boundaries of Kant’s categorical imperative to the point where it permits the committing of a crime against Hume’s three principles of justice, it shall be demonstrated how far the area is in which these two concepts persist alongside each other and how narrow the border zone is in which they do not. Indeed, the latter is a forbidden place that can only be accessed through destiny and never by choice. Whoever is witnessed to stay there, must wish for Justice to draw her sword against him, and whoever dares to try reaching it, will only wander about a deserted land where both justice and morality are left behind.

The main objects of study in this thesis are abelian varieties and their endomorphism rings. Abelian varieties are not just interesting in their own right, they also have numerous applications in various areas such as in algebraic geometry, number theory and information security. In fact, they make up one of the best choices in public key cryptography and more recently in post-quantum cryptography. Endomorphism rings are objects attached to abelian varieties. Their computation plays an important role in explicit class field theory and in the security of some post-quantum cryptosystems. There are subexponential algorithms to compute the endomorphism rings of abelian varieties of dimension one and two. Prior to this work, all these subexponential algorithms came with a probability of failure and additional steps were required to unconditionally prove the output. In addition, these methods do not cover all abelian varieties of dimension two. The objective of this thesis is to analyse the subexponential methods and develop ways to deal with the exceptional cases. We improve the existing methods by developing algorithms that always output the correct endomorphism ring. In addition to that, we develop a novel approach to compute endomorphism rings of some abelian varieties that could not be handled before. We also prove that the subexponential approaches are simply not good enough to cover all the cases. We use some of our results to construct a family of abelian surfaces with which we build post-quantum cryptosystems that are believed to resist subexponential quantum attacks - a desirable property for cryptosystems. This has the potential of providing an efficient non interactive isogeny based key exchange protocol, which is also capable of resisting subexponential quantum attacks and will be the first of its kind.

Membrane proteins are of high pharmacological interest as they are involved in a variety of vital functions. However, to make them accessible to in vitro studies, they often need to be extracted from their natural lipid environment and stabilized with the aid of membrane-mimetic systems. Such membrane mimics can consist of diverse amphiphilic molecules. Small-molecule amphiphiles that can solubilize lipid bilayers, so-called detergents, have been invaluable tools for membrane-protein research in recent decades. Herein, novel small-molecule glyco-amphiphiles embodying three distinct design principles are introduced, and their biophysical and physicochemical properties are investigated. In doing so, the major aims consist in establishing new promising amphiphiles and in determining structure–efficacy relationships for their synthesis and application. First, the software package D/STAIN was introduced to facilitate the analysis of demicellization curves obtained by isothermal titration calorimetry. The robustness of the underlying algorithm was demonstrated by analyzing demicellization curves representing large variations in amphiphile concentrations and thermodynamic parameters. Second, the interactions of diastereomeric cyclopentane maltoside amphiphiles (CPMs) with lipid bilayers and membrane proteins were investigated. To this end, lipid model membranes, cellular membranes, and model membrane proteins were treated with different stereoisomer CPMs. These investigations pointed out the importance of stereochemical configuration in the solubilization of lipid bilayers, in the extraction of membrane proteins, and, ultimately, in the stabilization of the latter. Ultimately, CPM C12 could be identified as a particularly stabilizing agent. Third, the influence of a polymerizable group attached to detergent-like amphiphiles was characterized regarding their micellization, micellar properties, and ability to solubilize lipid membranes. This revealed that such chemical modifications can have different degrees of impact regarding the investigated properties. In particular, micellization was influenced substantially, whereas the sizes of the resulting micelles varied slightly. The polymerizable amphiphiles were shown to solubilize artificial and natural lipid membranes and, consequently, to extract membrane proteins. Last, the self-assembly of diglucoside amphiphiles bearing either a hydrocarbon or a lipophobic fluorocarbon chain to form native nanodiscs was investigated. It was shown that the presence of a fluorocarbon hydrophobic chain conveys superior stabilization properties onto the amphiphile and the resulting nanodiscs. Moreover, the kinetics of lipid exchange were fundamentally altered by the presence of the fluorocarbon amphiphiles in the nanodisc rim.

Industrial manufacturing companies have different IT control functions that can be represented with a so-called hierarchical automation pyramid. While these conventional software systems especially support the mass production with consistent demand, the future project “Industry 4.0” focuses on customer-oriented and adaptable production processes. In order to move from conventional production systems to a factory of the future, the control levels must be redistributed. With the help of cyber-physical production systems, an interoperable architecture must be, implemented which removes the hierarchical connection of the former control levels. The accompanied digitalisation of industrial companies makes the transition to modular production possible. At the same time, the requirements for production planning and control are increasing, which can be solved with approaches such as multi-agent systems (MASs). These software solutions are autonomous and intelligent objects with a distinct collaborative ability. There are different modelling methods, communication and interaction structures, as well as different development frameworks for these new systems. Since multi-agent systems have not yet been established as an industrial standard due to their high complexity, they are usually only tested in simulations. In this bachelor thesis, a detailed literature review on the topic of MASs in the field of production planning and control is presented. In addition, selected multi-agent approaches are evaluated and compared using specific classification criteria. In addition, the applicability of using these systems in digital and modular production is assessed.

In recent months, sustainable development and the achievement of the United Nations Sus- tainable Development Goals has gained unprecedented prominence. SDG 7 aspires to achieve access to electricity for the entire world population by 2030 and - at the same time - to significantly increase the share of renewable energy in the power mix. This target trans- lates into ambitious electricity supply and renewable energy asset growth scenarios for Sub- Saharan Africa, the least developed region worldwide. Though theoretical renewable energy potential is abundant and capital generally available, progress has been slow. Aside funds from donors and Development Finance Institutions, private commercial capital is required to accelerate the progress. Project Finance has successfully attracted private funds for renew- able energy assets in other jurisdictions but has played a negligible role in the energy tran- sition in Sub-Saharan Africa. A variety of reasons are identified that impede their implemen- tation, which are categorised into (i) unsatisfactory project pre-requisites and preparation, (ii) challenging host country conditions, (iii) elevated non-financial project risks and (iv) risky financial transaction structures. While a review of potential mitigation measures reveals that the risk factors are theoretically addressable, most require a multi-stakeholder alignment and exhibit some implementation complexity. Putting them into practice will therefore take time and will require a high level of commitment from host governments, sponsors, and fi- nancial institutions. While pressure and urgency are mounting, time will tell whether the pro- ject parties are more successful going forward.

In the field of measurement technology, the use of unmanned aerial vehicles is becoming more and more popular. For many measurement tasks, the use of such devices offers many advantages in terms of cost and measurement effort. However, the occurring vibrations and disturbances are a significant disadvantage for the application of these devices for several measurement tasks. Within the scope of this work, a platform for measurement devices is developed. The platform is designed specifically for use on drones. The task of the platform is to isolate measurement equipments mounted on it from the drone disturbances. For this purpose we go through the product development process according to VDI 2221 to design a mechanical model of the platform. Then, control strategies are applied to isolate the platform. Since the disturbances acting on a drone are not always stationary, two control strategies known for their ability to handle uncertain systems are used. One of them comes from the field of acoustic.

Der Terminus der „Geringqualifizierten“ ist eine ebenso verbreitete wie eingeschränkte Beschreibung einer heterogenen Zielgruppe, welche vor dem Hintergrund steigender arbeitsmarktbezogener Kompetenzanforderungen sowie des Zusammenhangs zwischen formalem Bildungsstatus und Risiken der Erwerbslosigkeit im Zentrum arbeitsmarktpolitischer Diskussionen steht. Geringqualifizierung drückt sich nicht nur im Fehlen formaler, berufsqualifizierender Abschlüsse aus, sondern besitzt angesichts sich dynamisch verändernder Arbeitsfelder und Anforderungen an die Qualifikation der Mitarbeitenden auch eine relative Dimension. So können vorhandene Kompetenzen aufgrund fehlender Aktualisierung veralten und damit als „zu gering“ eingestuft werden. Vor diesem Hintergrund nähert sich der Bericht der Personengruppe der Geringqualifizierten an, indem er bestehende Definitionen kritisch betrachtet, Verbindungen zu anderen Begriffen aufzeigt und aus den Erkenntnissen eine eigene relative Beschreibung ableitet. Ergänzt wird dieser Report durch die Betrachtung von Weiterbildungsangeboten für diese Zielgruppe.

Untersucht wurde das mechanische Verformungsverhalten des massiven metallischen Glases Zr52,5Cu17,9Ni14,6Al10Ti5 (Vitreloy 105) an Luft und im wässrigen Umgebungsmedium 0,01 M Na2SO4 (+ 0,01 M NaCl). Die Belastung erfolgte im Dreipunktbiegeversuch unter quasistatischer sowie zyklischer Beanspruchung und mit Hilfe der instrumentierten Schlagprüfung. Neben dem Umgebungseinfluss wurde der Effekt von zyklisch-kryogenen Vorbehandlungen und Oberflächenbearbeitungen mittels Mikrostrahlen, -fräsen, -erodieren und -laserablation auf die Schädigungsentwicklung und die ertragbaren Spannungen analysiert. Während eine Modifikation der Oberfläche stets in einer Erhöhung der Plastizität infolge einer verstärkten Scherbandbildung resultierte, wiesen diese Proben i.d.R. deutlich niedrigere Dauerfestigkeiten unter zyklischer Wechselbeanspruchung auf. Die tiefkühlbehandelten Zustände zeigten in allen mechanischen Tests ein optimiertes Verformungsverhalten. Mit Hilfe der anodischen Polarisation wurde außerdem im chloridhaltigen Medium ein signifikanter Effekt auf die Lebensdauer der unbehandelten Ermüdungsproben verzeichnet. Die Detektion der scherbandgetriebenen Deformationsprozesse sowie der Rissinitiierung und -ausbreitung erfolgte sowohl mittels Licht- und Rasterelektronenmikroskopie als auch unter Ausnutzung elektrochemischer Messsignale im wässrigen Medium bzw. resistometrischer Methoden an Luft. Auf Basis der Untersuchungsergebnisse wurden abschließend Schädigungsmodelle für die jeweiligen Versuchsbedingungen aufgestellt und diskutiert.

Die Felix-Klein-Modellierungswoche ist eine Projektwoche für Schülerinnen und Schüler der gymnasialen Oberstufe. Wir beschreiben hier die Projekte, die während der Modellierungswoche im Februar 2022 durchgeführt wurden. Der Themenschwerpunkt der Veranstaltung lautete "Winter".

Das Allgemeine Gleichbehandlungsgesetz hat durch seine gesetzlich verankerten Regelungen bedeutsame Auswirkungen auf die Personalbeschaffung und birgt deshalb für Unternehmen gewisse Risiken im Rahmen des Prozesses rund um das Thema Stellenausschreibungen. Die Mastarbeit gibt neben Beispielen zu diskriminierenden Stellenanzeigen, einen Einblick in mögliche Rechtsfolgen für Unternehmen im Zusammenhang mit diskriminierenden Stellenanzeigen, sowie Handlungsempfehlungen zur Umsetzung von diskriminierungsfreien Stellenanzeigen.

A double dissociation impressively demonstrates that visual perception and visual awareness can be independent of each other and do not have to rely on the same source of information (T. Schmidt & Vorberg, 2006). Traditionally, an indirect measure of stimulus processing and a direct measure of visual awareness are compared (dissociation paradigm or classic dissociation paradigm, Erdelyi, 1986; formally described by Reingold & Merikle, 1988; Merikle & Reingold, 1990; Reingold, 2004). If both measures exhibit opposite time courses, a double dissociation is demonstrated. One tool that is well suited to measure stimulus processing as fast visuomotor response activation is the response priming method (Klotz & Neumann, 1999; Klotz & Wolff, 1995; see also F. Schmidt et al., 2011; Vorberg et al., 2003). Typically, observers perform speeded responses to a target stimulus preceded by a prime stimulus, which can trigger the same motor response by sharing consistent features (e.g., shape) or different responses due to inconsistent features. While consistent features cause speeded motor responses, inconsistent trials can induce response conflicts and result in slowed responses. These response time differences describe the response priming effect (Klotz & Neumann, 1999; Klotz & Wolff, 1995; see also F. Schmidt et al., 2011; Vorberg et al., 2003). The theoretical background of this method forms the Rapid-Chase Theory (T. Schmidt et al., 2006, 2011; see also T. Schmidt, 2014), which assumes that priming is based on neuronal feedforward processing within the visuomotor system. Lamme and Roelfsema (2000; see also Lamme, 2010) claim that this feedforward processing does not generate visual awareness because neuronal feedback and recurrent processes are needed. Fascinatingly, while prime visibility can be manipulated by visual masking techniques (Breitmeyer & Öğmen, 2006), priming effects can still increase over time. Masking effects are used as a direct measure of prime awareness. Based on their time course, type-A and type-B masking functions are distinguished (Breitmeyer & Öğmen, 2006; see also Albrecht & Mattler, 2010, 2012, 2016). Type-A masking is most commonly shown with a typically increasing function over time. In contrast, type-B masking functions are rarely observed, which demonstrate a decreasing or u-shaped time course. This masking type is usually only found under metacontrast backward masking (Breitmeyer & Öğmen, 2006; see also Albrecht & Mattler, 2010, 2012, 2016). While priming effects are expected to increase over time by Rapid-Chase Theory (T. Schmidt et al., 2006, 2011; see also T. Schmidt, 2014), the masking effect can show an opposite trend with a decreasing or u-shaped type-B masking curve, forming a double dissociation. In empirical practice, double dissociations are a rarity, while historically simple dissociations have been the favored data pattern to demonstrate perception without awareness, despite suffering from statistical measurement problems (T. Schmidt & Vorberg, 2006). Motivated by this shortcoming, I aim to demonstrate that a double dissociation is the most powerful and convincing data pattern, which provides evidence that visual perception does not necessarily generate visual awareness, since both processes are based on different neuronal mechanisms. I investigated which experimental conditions allow for a double dissociation between priming and prime awareness. The first set of experiments demonstrated that a double-dissociated pattern between priming and masking can be induced artificially, and that the technique of induced dissociations is of general utility. The second set of experiments used two awareness measures (objective vs. subjective) and a response priming task in various combinations, resulting in different task settings (single-, dual-, triple tasks). The experiments revealed that some task types constitute an unfavorable experimental environment that can prevent a double dissociation from occurring naturally, especially when a pure feedforward processing of the stimuli seems to be disturbed. The present work provides further important findings. First, stimulus perception and stimulus awareness show a general dissociability in most of the participants, supporting the idea that different neuronal processes are responsible for this kind of data pattern. Second, any direct awareness measure (no matter whether objective or subjective) is highly observer-dependent, requiring the individual analysis at the level of single participants. Third, a deep analysis of priming effects at the micro level (e.g., checking for fast errors) can provide further insights regarding information processing of different visual stimuli (e.g., shape vs. color) and under changing experimental conditions (e.g. single- vs. triple tasks).

The knowledge of structural properties in microscopic materials contributes to a deeper understanding of macroscopic properties. For the study of such materials, several imaging techniques reaching scales in the order of nanometers have been developed. One of the most powerful and sophisticated imaging methods is focused-ion-beam scanning electron microscopy (FIB-SEM), which combines serial sectioning by an ion beam and imaging by a scanning electron microscope. FIB-SEM imaging reaches extraordinary scales below 5 nm with large representative volumes. However, the complexity of the imaging process results in the addition of artificial distortion and artifacts generating poor-quality images. We introduce a method for the quality evaluation of images by analyzing general characteristics of the images as well as artifacts exclusively for FIB-SEM, namely curtaining and charging. For the evaluation, we propose quality indexes, which are tested on several data sets of porous and non-porous materials with different characteristics and distortions. The quality indexes report objective evaluations in accordance with visual judgment. Moreover, the acquisition of large volumes at high resolution can be time-consuming. An approach to speed up the imaging is by decreasing the resolution and by considering cuboidal voxel configurations. However, non-isotropic resolutions may lead to errors in the reconstructions. Even if the reconstruction is correct, effects are visible in the analysis. We study the effects of different voxel settings on the prediction of material and flow properties of reconstructed structures. Results show good agreement between highly resolved cases and ground truths as is expected. Structural anisotropy is reported as resolution decreases, especially in anisotropic grids. Nevertheless, gray image interpolation remedies the induced anisotropy. These benefits are visible at flow properties as well. For highly porous structures, the structural reconstruction is even more difficult as a consequence of deeper parts of the material visible through the pores. We show as an application example, the reconstruction of two highly porous structures of optical layers, where a typical workflow from image acquisition, preprocessing, reconstruction until a spatial analysis is performed. The study case shows the advantages of 3D imaging for optical porous layers. The analysis reveals geometrical structural properties related to the manufacturing processes.

Durch die zunehmende Erzeugungsleistung auf Niederspannungsnetzebene (NS-Netzebene) durch Photovoltaikanlagen, sowie die Elektrifizierung des Wärme- und des Verkehrssektors sind Investitionen in die NS-Netze notwendig. Ein höherer Digitalisierungsgrad im NS-Netz birgt das Potential, die notwendigen Investitionen genauer zu identifizieren, und damit ggf. zu reduzieren oder zeitlich zu verschieben. Hierbei stellt die Markteinführung intelligenter Messsysteme, sog. Smart Meter, eine neue Möglichkeit dar, Messwerte aus dem NS-Netz zu erhalten und auf deren Grundlage die Stellgrößen verfügbarer Aktoren zu optimieren. Dazu stellt sich die Frage, wie Messdaten unterschiedlicher Messzyklen in einem Netzautomatisierungssystem genutzt werden können und wie sich das nicht-lineare ganzzahlige Optimierungsproblem der Stellgrößenoptimierung effizient lösen lässt. Diese Arbeit befasst sich mit der Lösung des Optimierungsproblems. Dazu kommt eine Stellgrößenoptimierung nach dem Merit-Order-Prinzip zur Anwendung.

Sequence learning describes the process of understanding the spatio-temporal relations in a sequence in order to classify it, label its elements or generate new sequences. Due to the prevalence of structured sequences in nature and everyday life, it has many practical applications including any language related processing task. One particular such task that has seen recent success using sequence learning techniques is the optical recognition of characters (OCR). State-of-the-art sequence learning solutions for OCR achieve high performance through supervised training, which requires large amounts of transcribed training data. On the other hand, few solutions have been proposed on how to apply sequence learning in the absence of such data, which is especially common for hard to transcribe historical documents. Rather than solving the unsupervised training problem, research has focused on creating efficient methods for collecting training data through smart annotation tools or generating synthetic training data. These solutions come with various limitations and do not solve all of the related problems. In this work, first the use of erroneous transcriptions for supervised sequence learning is introduced and it is described how this concept can be applied in unsupervised training scenarios by collecting or generating such transcriptions. The proposed OCR pipeline reduces the need of domain specific expertise to apply OCR, with the goal of making it more accessible. Furthermore, an approach for evaluating sequence learning OCR models in the absence of reference transcriptions is presented and its different properties compared to the standard method are discussed. In a second approach, unsupervised OCR is treated as an alignment problem between the latent features of the different language modalities. The outlined solution is to extract language properties from both the text and image domain through adversarial training and learn to align them by adding a cycle consistency constraint. The proposed approach has some strict limitations on the input data, but the results encourage future research into more widespread applications.

Reinforcing sand soils using tyre rubber chips is a novel technology that is under investigation to optimize its engineering application. Previous studies concentrated on static behaviour and very few on cyclic and dynamic behaviour of sand rubber mixtures leaving gaps that need to be addressed. This research focuses on evaluating the static, cyclic and dynamic behaviours of sand rubber mixtures. The basic properties of sands S2, S3, S4, rubber chips and sand rubber chips mixtures at 10/20/30% rubber chips content by dry mass were first evaluated in order to obtain the parameters essential for subsequent testing. Oedometer, direct shear with larger box 300x300 mm and static triaxial compression tests were performed to assess the static behaviour of the composite material. Further, dynamic cyclic triaxial tests were performed to evaluate the cyclic behaviour of saturated, dry and wet mixtures. All specimens were first isotropically consolidated at 100 kPa. For saturated material a static deviatoric stress of 45 kPa was imposed prior to cycling to simulate the field anisotropic consolidation condition. Cycling was applied stress-controlled with amplitude of 50kPa. Both undrained and drained tests were performed. Cyclic tests in dry or wet conditions were also performed under anisotropic consolidation condition with the application of different stress amplitudes. For all cyclic tests the loading frequency was 1 Hz. With regard to dynamic behaviour of the mixtures, the resonant column tests were conducted. Calibration was first performed yielding a frequency dependent drive head inertia. Wet mixture specimens were prepared at relative density of 50% and tested at various confining stresses. Note that all specimens tested in both triaxial and resonant column were 100 mm diameter. The results from the entire investigation are promising. In summary, rubber chips in the range of 4 to 14 mm mixed with sands were found to increase the shear resistance of the mixtures. They yield an increase of the cyclic resistance under saturated condition, to a decrease of stiffness and to an increase of damping ratio. Increased confining stress increased the shear modulus reduction and decreased damping ratio of the mixtures. Increased rubber content increased both shear modulus reduction and damping ratio. Several new design equations were proposed that can be used to compute the compression deformation, pore pressure ratio, maximum shear modulus and minimum damping ratio, as well as the modulus reduction with shear strain. Finally, chips content around 20% to 30% by dry mass can be used to reinforce sandy soils. The use of this novel composite material in civil engineering application could consume a large volume of scrap tyres and at the same time contribute to cleaning environment and saving natural resources.

Verkündungsblatt der TU Kaiserslautern Nr. 2/17.02.2022

The hazard and operability (HAZOP) method is widely used in chemical and process industries to identify and evaluate hazards. Due to its human-centered nature, it is time-consuming, and the results depend on the team composition. In addition, the factors time pressure, type of implementation, experience of the participants, and participant involvement affect the results. This research aims to digitize the HAZOP method. The investigation shows that knowledge-based systems with ontologies for knowledge representation are suitable to achieve the objective. Complex interdisciplinary knowledge regarding facility, process, substance, and site information must be represented to perform the task. A result of this work is a plant part taxonomy and a developed object-oriented equipment entity library. During ontology development, typical HAZOP scenarios, as well as their structure, components, and underlying causal model, were investigated. Based on these observations, semantic relationships between the scenario components were identified. The likelihood of causes and severity of consequences were determined as part of an automatic risk assessment using a risk matrix to determine safeguards reliably. An inference algorithm based on semantic reasoners and case-based reasoning was developed to exploit the ontology and evaluate the input data object containing the plant representation. With consideration given to topology, aspects like the propagation of sub-scenarios through plant parts were considered. The results of the developed knowledge-based system were automatically generated HAZOP worksheets. Evaluation of the achieved results was based on representative case studies in which the relevance, comprehensibility, and completeness of the automatically identified scenarios were considered. The achieved results were compared with conventionally prepared HAZOP tables for benchmark purposes. By paying particular attention to the causal relationships between scenario components, the risk assessment, and with consideration of safeguards, the quality of the automatically generated results was comparable to conventional HAZOP worksheets. This research shows that formal ontologies are suitable for representing complex interdisciplinary knowledge in the field of process and plant safety. The results contribute to the use of knowledge-based systems for digitizing the HAZOP method. When used correctly, knowledge-based systems can help decrease the preparation time and repetitious nature of HAZOP studies and standardize results.

We present an identification benchmark data set for a full robot movement with an KUKA KR300 R2500 ultra SE industrial robot. It is a robot with a nominal payload capacity of 300 kg, a weight of 1120 kg and a reach of 2500mm. It exhibits 12 states accounting for position and velocity for each of the 6 joints. The robot encounters backlash in all joints, pose-dependent inertia, pose-dependent gravitational loads, pose-dependent hydraulic forces, pose- and velocity dependent centripetal and Coriolis forces as well as a nonlinear friction, which is temperature dependent and therefore potentially time varying. We supply the prepared dataset for black-box identification of the forward or the inverse robot dynamics. Additional to the data for black-box modelling, we supply high-frequency raw data and videos of each experiment. A baseline and figures of merit are defined to make results compareable across different identification methods.

Recommender systems recommend items (e.g., movies, products, books) to users. In this thesis, we proposed two comprehensive and cluster-induced recommendation-based methods: Orthogonal Inductive Matrix Completion (OMIC) and Burst-induced Multi-armed Bandit (BMAB). Given the presence of side information, the first method is categorized as context-aware. OMIC is the first matrix completion method to approach the problem of incorporating biases, side information terms and a pure low-rank term into a single flexible framework with a well-principled optimization procedure. The second method, BMAB, is context-free. That is, it does not require any side data about users or items. Unlike previous context-free multi-armed bandit approaches, our method considers the temporal dynamics of human communication on the web and treats the problem in a continuous time setting. We built our models' assumptions under solid theoretical foundations. For OMIC, we provided theoretical guarantees in the form of generalization bounds by considering the distribution-free case: no assumptions about the sampling distribution are made. Additionally, we conducted a theoretical analysis of community side information when the sampling distribution is known and an adjusted nuclear norm regularization is applied. We showed that our method requires just a few entries to accurately recover the ratings matrix if the structure of the ground truth closely matches the cluster side information. For BMAB, we provided regret guarantees under mild conditions that demonstrate how the system's stability affects the expected reward. Furthermore, we conducted extensive experiments to validate our proposed methodologies. In a controlled environment, we implemented synthetic data generation techniques capable of replicating the domains for which OMIC and BMAB were designed. As a result, we were able to analyze our algorithms' performance across a broad spectrum of ground truth regimes. Finally, we replicated a real-world scenario by utilizing well-established recommender datasets. After comparing our approaches to several baselines, we observe that they achieved state-of-the-art results in terms of accuracy. Apart from being highly accurate, these methods improve interpretability by describing and quantifying features of the datasets they characterize.

Grinding is one of the effective manufacturing processes with which to produce highly accurate parts with an ultra-fine surface finish. The tool used to remove materials in grinding is called the grinding wheel. Abrasive grains made of extremely hard materials (alumina, silica, cubic boron nitride, and diamond) having a definite grit size but a random shape are bonded on the circumferential surface of the grinding wheel. The fabrication process is controlled so that the wheel exhibits a prescribed structure (in the scale of soft to hard). At the same time, the distribution of grains must follow a prescribed grade (in the scale of dense to open). After the fabrication, the wheel is dressed to make sure of its material removal effectiveness, which itself depends on the surface topography. The topography is quantified by the distribution and density of active abrasive grains located on the circumferential surface, the grains’ protrusion heights, and their pore volume ratio. The prediction of the surface topography mentioned above requires a model that considers the entire manufacturing process and the influences on the grinding wheel properties. This study fills this gap in modelling the grinding wheel by presenting a surface topography model and simulation framework for the effect of the grinding wheel fabrication process on the surface topography. The simulation results have been verified by conducting experiments. This study will thus help grinding wheel manufacturers in developing more effective grinding wheels.

The scaffolding protein family Fe65, composed of Fe65, Fe65L1, and Fe65L2, was identified as an interaction partner of the amyloid precursor protein (APP), which plays a key function in Alzheimer’s disease. All three Fe65 family members possess three highly conserved interaction domains, forming complexes with diverse binding partners that can be assigned to different cellular functions, such as transactivation of genes in the nucleus, modulation of calcium homeostasis and lipid metabolism, and regulation of the actin cytoskeleton. In this article, we rule out putative new intracellular signaling mechanisms of the APP-interacting protein Fe65 in the regulation of actin cytoskeleton dynamics in the context of various neuronal functions, such as cell migration, neurite outgrowth, and synaptic plasticity.

This review aims to provide a concise overview of the role of (digital) data and new data practices in schools. By focusing on the impact of data on pedagogical practices, it aims to shed light on how the everyday tasks of teachers and other pedagogical staff in schools are changing, particularly as a result of the generation and use of digital data. For this purpose, existing studies and previous theoretical debates on this topic are examined for their perspectives on data and data practices in schools. The pedagogical data practices of (improving) teaching and learning, assessment and counseling, (data-driven) decision-making, and cooperation and collaboration by “doing data” will be elaborated and discussed. Likewise, data practices that are missing from the studies are identified. We conclude with an overview of blind spots and further research needs.

Impaired genome integrity has severe consequences for the viability of any cell. Unrepaired DNA lesions can lead to genomically unstable cells, which will often become predisposed for malignant growth and tumorigenesis, where genomic instability turns into a driving factor through the selection of more aggressive clones. Aneuploidy and polyploidy are both poorly tolerated in somatic cells, but frequently observed hallmarks of cancer. Keeping the genome intact requires the concentrated action of cellular metabolism, cell cycle and DNA damage response. This study presents multi-omics analysis as a versatile tool to understand the various causes and consequences of impaired genome integrity. The possible computational approaches are demonstrated on three different datasets. First, an analysis of a collection of DNA repair experiments is shown, which features the creation of a high-fidelity dataset for the identification and characterization of DNA damage factors. Additionally, a web-application is presented that allows scientists without a computational background to interrogate this dataset. Further, the consequences of chromosome loss in human cells are analyzed by an integrated analysis of TMT labeled mass spectrometry and sequencing data. This analysis revealed heterogeneous cellular responses to chromosome losses that differ from chromosome gains. My analysis further revealed that cells possess both transcriptional and post-transcriptional mechanisms that compensate for the loss of genes encoded on a monosomic chromosome to alleviate the detrimental consequences of reduced gene expression. In my final project, I present a multi-omics analysis of data obtained from SILAC labeled mass spectrometry and dynamic transcriptome analysis of yeast cells of different ploidy, from haploidy to tetraploid. This analysis revealed that unlike cell volume, the proteome of a cell does not scale linearly with increasing ploidy. While the expression of most proteins followed this scaling, several proteins showed ploidy-dependent regulation that could not be explained by transcriptome expression. Hence, this ploidy-dependent regulation occurs mostly on a post-transcriptional level. The analysis uncovered that ribosomal and translation related proteins are downregulated with increasing ploidy, emphasizing a remodeling of the cellular proteome in response to increasing ploidy to ensure survival of cells after whole genome doubling. Altogether this study intends to show how state-of-the-art multi-omics analysis can uncover cellular responses to impaired genome integrity in a highly diverse field of research.

Acrylamid ist eine α,β-ungesättigte Carbonylverbindung, die beim Erhitzen von Lebensmitteln durch die Maillard-Reaktion aus Aminosäuren wie Asparagin und reduzierenden Zuckern gebildet wird. Da für diese prozessbedingte Lebensmittelkontaminante neuro- und gentoxische Effekte beschrieben sind und die mittlere alimentäre Exposition in Europa auf 0,4–1,9 μg/kg KG/d geschätzt wurde, ist Acrylamid von Bedeutung für die Risikobewertung von Lebensmitteln. Acrylamid und sein gentoxischer Metabolit Glycidamid werden zu den Mercaptursäuren N-Acetyl-S-(2-carbamoylethyl)-L-cystein (AAMA) bzw. N-Acetyl-S-(2-hydroxy-2-carbamoylethyl)-L-cystein (GAMA) metabolisiert, die als renale Biomarker zur Abschätzung der internen Exposition Verwendung finden. Frühere Befunde deuteten bereits auf eine potentielle endogene Bildung hin, die einer Acrylamid-Exposition von 0,2–0,7 µg/kg KG entsprach und somit nennenswert zur Biomarker-Ausscheidung beitragen kann, die exogen durch Acrylamid-Aufnahme durch Lebensmittel, Tabakrauch oder Exposition am Arbeitsplatz beeinflusst werden kann. Um diese verschiedenen Einflussfaktoren weiter zu untersuchen, wurden zwei Humanstudien durchgeführt. Im Rahmen einer Duplikat-Studie unter streng kontrollierten Bedingungen wurde die Toxikokinetik der Mercaptursäuren und Hämoglobin-Addukte nach Acrylamid-Aufnahme durch den Verzehr von Kaffee (0,15–0,17 µg/kg KG/d) bzw. hitzebehandelten Lebensmitteln (14,1–15,9 μg/kg KG/d) in sechs Probanden untersucht. Während der Kaffeekonsum nur zu einer leicht erhöhten Mercaptursäure-Antwort führte, konnte die renale Ausscheidungskinetik nach Aufnahme von 14,1–15,9 μg/kg KG/d Acrylamid erfasst werden. Weitere sechs Probanden erhielten eine Acrylamid-minimierte Diät, die eine Acrylamid-Aufnahme von 0,05–0,06 µg/kg KG/d nicht überschritt (Washout), und zusätzlich einen einmaligen Bolus von 1 μg/kg KG 13C3D3-Acrylamid. Am Ende des 13-tägigen Washout wurde ein AAMA-Level erfasst, das einer Hintergrundbelastung von 0,3–0,4 µg/kg KG/d entsprach, während die Ausscheidung von 13C3D3-Acrylamid als 13C3D3-AAMA innerhalb von 72–96 h praktisch abgeschlossen war, welches die Hypothese einer anhaltenden endogenen Acrylamid-Bildung in vivo unterstützt. Dies wurde durch Modell-Reaktionen untermauert, die eine Acrylamid-Bildung unter physiologischen Bedingungen zeigten. Eine zweite Duplikat-Studie mit Gemischtköstlern und Veganern befasste sich mit dem Einfluss der Ernährung und Lebensstils auf die Acrylamid-Exposition und Ausscheidung von AAMA, GAMA sowie Tabakrauch-Expositionsbiomarkern. Die mittlere Acrylamid-Aufnahme betrug 0,32±0,19 µg/kg KG/d, es zeigten sich jedoch deutliche Variabilitäten zwischen den Tagen und den Probanden. So nahmen Veganer mehr Acrylamid auf (0,38±0,23 µg/kg KG/d) als Gemischtköstler (0,26±0,10 µg/kg KG/d). Die Ausscheidungskinetik von AAMA und GAMA im Urin stimmte im Wesentlichen mit der jeweiligen alimentären Acrylamid-Aufnahme überein. Erhöhte Werte konnten auf eine umwelt-bezogene Belastung mit Tabakrauch zurückgeführt werden.

Multicore processors and Multiprocessor System-on-Chip (MPSoC) have become essential in Real-Time Systems (RTS) and Mixed-Criticality Systems (MCS) because of their additional computing capabilities that help reduce Size, Weight, and Power (SWaP), required wiring, and associated costs. In distributed systems, a single shared multicore or MPSoC node executes several applications, possibly of different criticality levels. However, there is interference between applications due to contention in shared resources such as CPU core, cache, memory, and network. Existing allocation and scheduling methods for RTS and MCS often rely on implicit assumptions of the constant availability of individual resources, especially the CPU, to provide guaranteed progress of tasks. Most existing approaches aim to resolve contention in only a specific shared resource or a set of specific shared resources. Moreover, they handle a limited number of events such as task arrivals and task completions. In distributed RTS and MCS with several nodes, each having multiple resources, if the applications, resource availability, or system configurations change, obtaining assumptions about resources becomes complicated. Thus, it is challenging to meet end-to-end constraints by considering each node, resource, or application individually. Such RTS and MCS need global resource management to coordinate and dynamically adapt system-wide allocation of resources. In addition, the resource management can dynamically adapt applications to changing availability of resources and maintains a system-wide (global) view of resources and applications. The overall aim of global resource management is twofold. Firstly, it must ensure real-time applications meet their end-to-end deadlines even in the presence of faults and changing environmental conditions. Secondly, it must provide efficient resource utilization to improve the Quality of Service (QoS) of co-executing Best-Effort (BE) (or non-critical) applications. A single fault in global resource management can render it useless. In the worst case, the resource management can make faulty decisions leading to a deadline miss in real-time applications. With the advent of Industry 4.0, cloud computing, and Internet-of-Things (IoT), it has become essential to combine stringent real-time constraints and reliability requirements with the need for an open-world assumption and ensure that the global resource management does not become an inviting target for attackers. In this dissertation, we propose a domain-independent global resource management framework for distributed RTS and MCS consisting of heterogeneous nodes based on multicore processors or MPSoC. We initially developed the framework with the French Aerospace Lab -- ONERA and Thales Research & Technology during the DREAMS project and later extended it during SECREDAS and other internal projects. Unlike previous resource management frameworks RTS and MCS, we consider both safety and security for the framework itself. To enable real-time industries to use cloud computing and enter a new market segment -- real-time operation as a cloud-based service, we propose a Real-Time-Cloud (RT-Cloud) based on global resource management for hosting RTS and MCS. Finally, we present a mixed-criticality avionics use case for evaluating the capabilities of the global resource management framework in handling permanent core failures and temporal overload condition, and a railway use case to motivate the use of RT-Cloud with global resource management.

Biertreber stellt einen wichtigen Vertreter eines nachwachsenden Rohstoffes dar, da es sich dabei um ein niedrigpreisiges Nebenprodukt des Brauprozesses handelt, welches jedes Jahr in großen Mengen anfällt. In der vorliegenden Arbeit wurde Biertreber aus sieben verschiedenen Braurezepten, sowohl aus eigener Herstellung als auch industriellen Ursprungs, analysiert und in Bezug auf die zugrundeliegenden Braugänge klassifiziert. Darüber hinaus wurde der Treber durch Pressen in zwei separate Stoffströme aufgeteilt: eine flüssige und eine feste Fraktion. Für beide Fraktionen wurden Bioprozesse etabliert, um einerseits das flüssige Substrat (Treberpresssaft) mit einem Milchsäurebakterium (Lactobacillus delbrueckii subsp. lactis) zu Milchsäure und andererseits das feste Substrat (Treberrückstand) mit einem lignocellulolytischen und gemischtsäuregärung-betreibenden Stamm (Cellulomonas uda) zu Ethanol und Essigsäure umzusetzen. Außerdem wurde ein kinetisches Modell aufgestellt, welches u.a. die Milchsäurebildung und das Zellwachstum von L. delbrueckii subsp. lactis für drei Treberpresssäfte unterschiedlicher Braurezepturen, d.h. mit unterschiedlicher Nährstoffausstattung, in einer simultanen Verzuckerung und Fermentation vorhersagen konnte. Des Weiteren konnten die entwickelten Fermentationsstrategien zur Verwertung des Treberpresssaftes und Treberrückstandes sowie die zugrundeliegenden Prozessüberwachungs- und Regelungsstrategien auf Fermentationen mit den gleichen Organismen aber dem Substrat Wiesenschnitt – also einen weiteren nachwachsenden Rohstoff – übertragen werden.

Der Klimawandel hat gravierende sowohl schleichende als auch plötzlich eintretende Folgen. Entwicklungsländer und hier besonders die ärmsten Länder sind hiervon massiv betroffen, da dort weitere sozio-ökonomische und andere Faktoren zu einer erhöhten Vulnerabilität bestimmter Bevölkerungsgruppen beitragen. Daraus resultiert eine wachsende klimabedingte Migration. 2019 sind etwa 3,5 % der Weltbevölkerung internationale Migranten. Migration ist multikausal. Wie viele Menschen aufgrund des Klimawandels emigrieren, ist daher schwer abschätzbar. Allerdings ist davon auszugehen, dass die Zahl zunehmen wird. Globale Governance spiegelt diese zunehmende Virulenz wider. Relevante Rahmenwerke wie der Global Compact for Migration, die Agenda 2030 und der Migrations- und Asylpakt der Europäischen Union werden in dieser Masterarbeit im Hinblick auf klimainduzierte Migration analysiert. Ein globales Rahmenwerk, das in der Lage wäre, klimainduzierte Migration zu regulieren, den Schutz Betroffener zu gewährleisten und das Phänomen im Sinne der nachhaltigen Entwicklung kohärent zu adressieren, existiert bislang nicht. Die Vielzahl der heranzuziehenden Rahmenwerke bedeutet eine Herausforderung für die internationale Zusammenarbeit, die diese Arbeit untersucht. Am Beispiel der Deutschen Gesellschaft für Internationale Zusammenarbeit GmbH als nationaler Durchführungsorganisation der deutschen Entwicklungszusammenarbeit wird diese Herausforderung anhand eines Fallbeispieles verdeutlicht.

Data is the new gold and serves as a key to answer the five W’s (Who, What, Where, When, Why) and How’s of any business. Companies are now mining data more than ever and one of the most important aspects while analyzing this data is to detect anomalous patterns to identify critical patterns and points. To tackle the vital aspects of timeseries analysis, this thesis presents a novel hybrid framework that stands on three pillars: Anomaly Detection, Uncertainty Estimation, and Interpretability and Explainability. The first pillar is comprised of contributions in the area of time-series anomaly detection. Deep Anomaly Detection for Time-series (DeepAnT), a novel deep learning-based anomaly detection method, lies at the foundation of the proposed hybrid framework and addresses the inadequacy of traditional anomaly detection methods. To the best of the author’s knowledge, Convolutional Neural Network (CNN) was used for the first time in Deep Anomaly Detection for Time-series (DeepAnT) to robustly detect multiple types of anomalies in the tricky and continuously changing time-series data. To further improve the anomaly detection performance, a fusion-based method, Fusion of Statistical and Deep Learning for Anomaly Detection (FuseAD) is proposed. This method aims to combine the strengths of existing wellfounded statistical methods and powerful data-driven methods. In the second pillar of this framework, a hybrid approach that combines the high accuracy of the deterministic models with the posterior distribution approximation of Bayesian neural networks is proposed. In the third pillar of the proposed framework, mechanisms to enable both HOW and WHY parts are presented.

The handling of oxygen sensitive samples and growth of obligate anaerobic organisms requires the stringent exclusion of oxygen, which is omnipresent in our normal atmospheric environment. Anaerobic workstations (aka. Glove boxes) enable the handling of oxygen sensitive samples during complex procedures, or the long-term incubation of anaerobic organisms. Depending on the application requirements, commercial workstations can cost up to 60.000 €. Here we present the complete build instructions for a highly adaptive, Arduino based, anaerobic workstation for microbial cultivation and sample handling, with features normally found only in high cost commercial solutions. This build can automatically regulate humidity, H2 levels (as oxygen reductant), log the environmental data and purge the airlock. It is built as compact as possible to allow it to fit into regular growth chambers for full environmental control. In our experiments, oxygen levels during the continuous growth of oxygen producing cyanobacteria, stayed under 0.03 % for 21 days without needing user intervention. The modular Arduino controller allows for the easy incorporation of additional regulation parameters, such as CO2 concentration or air pressure. This paper provides researchers with a low cost, entry level workstation for anaerobic sample handling with the flexibility to match their specific experimental needs.

Mit der Agenda 2030 für nachhaltige Entwicklung will die Staatengemeinschaft den globalen Herausforderungen gemeinsam unter Berücksichtigung der wirtschaftlichen, sozialen, ökologischen und politischen Dimension begegnen. Eine zunehmend fragile politische Weltlage prägt das Aufwachsen der jungen Generation und bedroht ihre Zukunft. Die 2015 von den Vereinten Nationen verabschiedeten 17 nachhaltigen Entwicklungsziele sind ein konkreter Aktionsplan, um die Welt bis zum Jahr 2030 zum Besseren zu verändern – auch für Kinder und Jugendliche und vor allem mit ihnen gemeinsam. Seit dem Jahr 2000 gibt es beachtliche Fortschritte bei der Erreichung des Ziels der universellen Grundschulbildung. Die Gesamteinschulungsrate erreichte 2015 in den Entwicklungsregionen 91 Prozent und die weltweite Zahl der Kinder, die nicht zur Schule gehen, ist um fast die Hälfte gesunken. Auch in Nepal wurden im Bildungssektor bedeutende Erfolge in Bezug auf Zugang und Teilhabe erzielt, insbesondere in den Bereichen Schulbildung, Alphabetisierung und Weiterbildung. Trotzdem gibt es in Nepal viele Kinder, darunter besonders viele Mädchen, die nicht zur Schule gehen oder diese abbrechen, weil die Familien sich den Schulbesuch nicht leisten können, die Schulen zu weit entfernt sind oder sie ethnischen Minderheiten angehören. Als zentrale Fragestellung der Masterarbeit soll das seit zehn Jahren bestehende UNICEF-Bildungsprogramm Let Us Learn in Nepal im Kontext der Agenda 2030 evaluiert werden. Es soll erforscht werden, inwieweit die Implementierung des Bildungsprogramms Let Us Learn von UNICEF in Nepal auf die SDGs einzahlt. In diesem Zusammenhang sollen die direkten Auswirkungen von Bildungsprogrammen für Kinder, insbesondere Mädchen, in Nepal mit Blick auf die 17 SDGs der Agenda 2030 eruiert werden. Gleichzeitig soll geklärt werden, ob und inwieweit bei diesen Bildungsprogrammen die Prinzipien der Paris-Deklaration über die Wirksamkeit von nachhaltiger Entwicklungszusammenarbeit, insbesondere die Eigenverantwortung der Empfängerländer und die gegenseitigen Rechenschaftspflicht Berücksichtigung finden. Mittels Experteninterviews von Personen aus dem direkten Umfeld der Entwicklungszusammenarbeit und mit Expertise zur Situation in Nepal sowie Fallstudien sollen die notwendigen Daten für die Analyse und Evaluation generiert werden. Ausgangspunkt der Forschungsfrage ist die Hypothese, dass das Erreichen einer inklusiven und qualitativ hochwertigen Bildung für alle (SDG 4) die Überzeugung bekräftigt, dass Bildung eines der stärksten und bewährtesten Mittel für eine nachhaltige Entwicklung ist. Erfolge im Bildungssektor sollen einen gleichberechtigten Zugang zu einer soliden Berufsausbildung erleichtern oder gar den Zugang zu einer hochwertigen Hochschulbildung ermöglichen und können somit dazu beitragen, Ungleichheiten zwischen den Geschlechtern zu beseitigen, Wohlstand zu schaffen, Armut und Hunger einzudämmen und damit die Chance auf Ernährungssicherheit zu erhöhen. Insbesondere Bildungsprojekte für Grundschüler haben große Potenziale, Chancen für Kinder zu eröffnen, frühzeitig für alle 17 SDGs der Agenda 2030 sensibilisiert zu werden.

Aufbauend auf früheren Arbeiten wurden Reduktionsversuche von [RCpNi(μ-Br)]2 (im Folgenden ist RCp stets C5H2tBu3-1,2,4 = Cp''' oder C5HiPr4 = 4Cp) in nicht-aromatischen Lösungsmitteln untersucht. Die Ausgangsverbindungen [Cp'''Ni(μ-Br)]2 und [4CpNi(μ-Br)]2 wurden synthetisiert und mit verschiedenen Hydridquellen zu [Cp'''Ni(μ-H)]2 und [4CpNi(μ-H)]2 umgesetzt. Die Umsetzung mit einem Äquivalent Kaliumhydroxid führte zu [(RCpNi)2(μ-Br)(μ-OH)]. [(RCpNi)2(μ-Br)(μ-H)] konnten nur als Produktgemisch mit [RCpNi(μ-Br)]2 oder [RCpNi(μ-H)]2 erhalten werden. Durch Reduktion von [Cp'''Ni(μ-Br)]2 in aromatischen Lösungsmitteln konnten [(Cp'''Ni)2(μ-Toluol)] und [(Cp'''Ni)2(μ-Benzol)] erhalten werden. Mit jeweils zwei Äquivalenten Triphenylphosphan, 1,3-Diisopropyl-4,5-dimethylimidazol-2- yliden und Diphenylacetylen wurden paramagnetische Komplexe mit 17 VE der Form [Cp'''Ni(L)] (L = PPh3, IiPr2Me2, C2Ph2) synthetisiert und röntgenkristallograpisch untersucht. Die einkernigen Ni(I)-Komplexe [Cp'''Ni(dppe)] und [Cp'''Ni(bipy)] zeigten im 1H-NMR-Spektrum keine Signale. Deren Entstehung konnte mittels ESI-MS belegt werden. Die Chlorido- und Iodido-verbrückten Cp''' - und 4Cp-Komplexe konnten ausgehend von [(RCpNi)2(μ-Toluol)] mit CuCl oder CuI erhalten werden. Mit einem Äquivalent Diphenylacetylen wurde der zweikernige Komplex [(Cp'''Ni)2(μ-C2Ph2)] erhalten, der in der Kristallstruktur eine Ni-Ni-Bindung zeigt. Der einkernige Ni(II)- Komplex [Cp'''Ni(TEMPO)] zeigte einen side-on koordinierten TEMPO-Liganden. Mittels NMR-Spektroskopie wurde für [(Cp'''Ni)2(μ-Toluol)] mit C6D6 ein Aromatenaustausch beobachtet. Die diamagnetischen Ni(II)-Komplexe [Cp'''NiCl(PPh3)], [Cp'''NiI(PPh3)], [Cp'''Ni(dppe)]Br und [Cp'''NiBr(IiPr2Me2)] konnten durch Umsetzung der entsprechenden Halogenido-verbrückten Cp'''Ni-Komplexe mit PPh3, IiPr2Me2 bzw. dppe erhalten werden. [Cp'''NiBr(IiPr2)] wurde durch Reaktion von [Cp'''NiN(SiMe3)2] mit 1,3-Diisopropylimidazoliumbromid erhalten. Ausgehend von [RCpNiN(SiMe3)2] wurden einkernige Nickelkomplexe mit Chelatliganden unter Eliminierung von HN(SiMe3)2 synthetisiert. Für [Cp'''Ni(8-hydroxychinolin)] konnte eine Kristallstruktur erhalten werden. [Cp'''Ni(naphthalimid)], [Cp'''Ni(curcumin)] und [4CpNi(curcumin)] wurden mittels NMR- und IR-Spektroskopie untersucht.

One of the most efficient measures to reduce energy consumption in buildings is using passive thermal comfort strategies. This paper shows the potential of coconut oil as a bio-based phase change material (PCM) incorporated into construction components to improve the thermal performance of buildings for several climates, due to its environmental advantages, wide availability, and economic feasibility. The thermophysical properties of coconut oil were determined through differential scanning calorimetry. Numerical simulations were conducted in ESP-r, comparing an office space with a gypsum ceiling to one with coconut oil as PCM for 12 climate types in the Köppen– Geiger classification. The results show that coconut oil is a suitable PCM for construction applications under tropical and subtropical climates. This PCM can provide year-round benefits for these climates, even though a higher melting point is needed for optimum performance during hotter months. The highest demand reduction of 32% and a maximum temperature reduction of 3.7 °C were found in Mansa, Zambia (Cwa climate). The best results occur when average outdoor temperatures are within the temperature range of phase change. The higher the diurnal temperature range, the better the results. Our findings contribute to a better understanding of coconut oil in terms of its properties and potential for application in the building sector as PCM.

Metal-directed self-assembly with metals such as Pd(II) and Pt(II), that prefer a square planar coordination geometry, has been showing remarkable potential to construct supramolecular architectures such as helices, tubes, locks and cages. Some of these complexes have also been shown to assemble by means of metal-metal interactions and, more remarkably, the luminescent properties of certain complexes can also be used for sensing. For instance, Pt(II) and Pd(II) complexes display strong phosphorescence which is strongly reduced in the presence of oxygen. The work developed for this thesis is divided into three main chapters dealing with the different properties of Pd(II) and Pt(II) metal complexes. Chapter I was mainly developed at Technische Universität Kaiserslautern with a short partnership with the Kekulé-Institut für Organische Chemie und Biochemie at the Universität Bonn and addressed the construction of coordination macrocycles and cages from suitable Pd(II) sources and cyclopeptide-derived ligands. Cyclopeptide derived hollow coordination compounds were obtained through Pd(II)-directed self-assembly. Specifically, the treatment of the pyridine containing cyclopeptides CP1 and CP2 with [Pd(en)(NO3)2] afforded the metallamacrocycle CP12Pd2 and the cage CP22Pd3. These products were characterized by means of NMR spectroscopy and mass spectrometry. The reaction between CP1 and [Pd(CH3CN)4](BF4)2] afforded, according to ESI-MS and NMR measurements, a complex with the composition CP16Pd3 and the smaller cage CP14Pd2. Binding studies indicated that CP12Pd2 incorporated different dicarboxylates, sodium 1,3- benzenedisulfonate (BDS), and sodium 2,6-naphthalenedisulfonate (NDS) into its cavity. In the case of BDS a 1:1 complex was formed that had a log Ka of 4.8 ± 0.2 in D2O/CD3OD, 1:1 (v/v). In the case of NDS, binding was slow on the NMR time-scale and involved the binding of two guest molecules as confirmed by a crystal structure of the complex. Based on these first examples of Pd(II)-containing cyclopeptide-derived coordination compounds, future work should focus on the design of molecular architectures that can, for example, be used as receptors for biorelevant guests. In Chapter II, the aggregation abilities and photophysical properties of Pt(II) complexes bearing tridentate-azolate-based ligands and cyclopeptides with peripheral pyridyl moieties were investigated. This project was the result of a short-term secondment developed at the Institut de Science et d'Ingénierie Supramoléculaires in Strasbourg. Efforts were made at creating luminescent cyclopeptide-derived Pt(II) complexes by coordinating CP1 or CP2 to suitable Pt(II)-containing precursors. The coordination of both peptides to a known Pt(II) complex afforded insoluble products that could not be characterized further. To circumvent these solubility issues, the synthesis of the analogous cyclopeptide complexes containing more polar ligands was attempted. Although mass spectrometry provided evidence for the formation of the target complexes PtDeg-CP1 and PtDeg-CP2 in the crude reaction mixtures, the products could not be isolated in pure form. The impure samples of PtDeg-CP1 and PtDegCP2 both exhibited orange emission. Further work is necessary to improve the preparation of such complexes. Only then can the characterization of their photophysical properties and self-assembling behavior be addressed. Chapter III was the result of a project executed at Micronit Micro Technologies B.V. in Enschede, in which a microfluidic device with oxygen sensing abilities was produced from nanoparticles containing Pt(II)-porphyrins. To this end, microfluidic devices containing the Pt(II) complex PtTPTBPF incorporated in different polymeric matrices were prepared and their oxygen sensing abilities characterized. It was shown that chips containing the Pt(II) complex incorporated into OXNANO nanoparticles were highly sensitive to oxygen, easy to fabricate, and allowed reliable oxygen quantification. Chips made by using other polymeric matrices such as PDMS, Elastosil®E43 or polystyrene were less suitable for the measurements. The OXNANO-containing chips furthermore allowed measuring the oxygen consumption of HUVEC cells in a biological assay even in repeated measurements. Future studies should now involve using these chips for monitoring in real time small scale biological processes.

In separation processes not only thermodynamic bulk but also interfacial properties play a crucial role. In classical theory, a vapour-liquid interface is a two-dimensional object. In reality it is a region in which properties change over a few nanometres and the density changes continuously from its liquid bulk to its gas bulk value. Many mixtures show unexpected effects in that transition region. While the total density changes monotonously from the bulk vapour to the bulk liquid, this does not hold for the molarities of the components. The molarities of the light boiling component can have a distinct maximum at the interface. That maximum would be an insurmountable obstacle to mass transfer according to Fickian theory. Even if that argument is not adopted, it shows that there is good reason to believe that the maximum may affect mass transfer and, hence, fluid separation processes like absorption or distillation. Unfortunately, there are currently no experimental methods that can be used for direct studies of density profiles in such interfacial regions. But such data can be obtained with theoretical methods, namely with molecular dynamics simulations (MD) as well as with density gradient theory (DGT) or with density functional theory (DFT) combined with an equation of state (EOS). Studies from our group on the vapour-liquid interface of several real mixtures and a model fluid using these methods yield consistent results and reveal an important enrichment in some cases. Strong enrichment is found at vapour-liquid interfaces in the systems in which one of the components is supercritical. These results indicate that mixtures, which are typical for absorption processes usually show an important enrichment, whereas this is not the case for mixtures that are typically separated by distillation.

In order to improve performance or conserve energy, modern hardware implementations have adopted weak memory models; that is, models of concurrency that allow more outcomes than the classic sequentially consistent (SC) model of execution. Modern programming languages similarly provide their own language-level memory models, which strive to allow all the behaviors allowed by the various hardware-level memory models, as well as those that can occur as a result of desired compiler optimizations. As these weak memory models are often rather intricate, it can be difficult for programmers to keep track of all the possible behaviors of their programs. It is therefore very useful to have an abstraction layer over the model that can be used to ensure program correctness without reasoning about the underlying memory model. Program logics are a way of constructing such an abstraction—one can use their syntactic rules to reason about programs, without needing to understand the messy details of the memory model for which the logic has been proven sound. Unfortunately, most of the work on formal verification in general, and program logics in particular, has so far assumed the SC model of execution. This means that new logics for weak memory have to be developed. This thesis presents two such logics—fenced separation logic (FSL) and weak separation logic (Weasel)—which are sound for reasoning under two different weak memory models. FSL considers the C/C++ concurrency memory model, supporting several of its advanced features. The soundness of FSL depends crucially on a specific strengthening of the model which eliminates a certain class of undesired behaviors (so-called out-of-thin-air behaviors) that were inadvertently allowed by the original C/C++ model. Weasel works under weaker assumptions than FSL, considering a model which takes a more fine-grained approach to the out-of-thin-air problem. Weasel's focus is on exploring the programming constructs directly related to out-of-thin-air behaviors, and is therefore significantly less feature-rich than FSL. Using FSL and Weasel, the thesis explores the key challenges in reasoning under weak memory models, and what effect different solutions to the out-of-thin-air problem have on such reasoning. It explains which reasoning principles are preserved when moving from a stronger to a weaker model, and develops novel proof techniques to establish soundness of logics under weaker models.

In past decades, many cities and regions have underwent structural transformations—e.g., in old industrialized “rust belts” or in peripheral rural areas. Many of these shrinking cities have to face the challenges of long-term demographic and economic changes. While shrinkage is often related to post-industrial transformations in the USA, in other countries, such as Germany, for example, the causes are related to changing demographics with declining birth rates and the effects of the German reunification. Many cities have tried to combat shrinkage and have thus developed a variety of policies and strategies such as the establishing of substitute industries. To assess the sustainability of this approach, this paper investigates the cities of Cleveland, USA and Bochum, Germany in a comparative analysis following the most similar/most different research design. The paper shows that substitute industries might lead to new development paths for shrinking cities.

Phototrophic biofilms, in particular terrestrial cyanobacteria, offer a variety of biotechnologically interesting products such as natural dyes, antibiotics or dietary supplements. However, phototrophic biofilms are difficult to cultivate in submerged bioreactors. A new generation of biofilm photobioreactors imitates the natural habitat resulting in higher productivity. In this work, an aerosol-based photobioreactor is presented that was characterized for the cultivation of phototrophic biofilms. Experiments and simulation of aerosol distribution showed a uniform aerosol supply to biofilms. Compared to previous prototypes, the growth of the terrestrial cyanobacterium Nostoc sp. could be almost tripled. Different surfaces for biofilm growth were investigated regarding hydrophobicity, contact angle, light- and temperature distribution. Further, the results were successfully simulated. Finally, the growth of Nostoc sp. was investigated on different surfaces and the biofilm thickness was measured noninvasively using optical coherence tomography. It could be shown that the cultivation surface had no influence on biomass production, but did affect biofilm thickness.

The nondestructive testing of multilayered materials is increasingly applied in both scientific and industrial fields. In particular, developments in millimeter wave and terahertz technology open up novel measurement applications, which benefit from the nonionizing properties of this frequency range. One example is the noncontact inspection of layer thicknesses. Frequently used measuring and analysis methods lead to a resolution limit that is determined by the bandwidth of the setup. This thesis analyzes the reliable evaluation of thinner layer thicknesses using model-based signal processing.

Getrieben durch nötige Energie- und Kosteneinsparungen finden Kunststoffe vermehrt Anwendung als Primärkomponenten in tribologischen Systemen. Der Trend zeichnet sich durch stete Forschung und Entwicklung hinsichtlich der Effektivität unterschiedlicher Materialkombinationen zur Reduktion von Reibung und Verschleiß aus, wobei die reibinduzierte Wärme zu den größten Herausforderungen zählt. Insbesondere bei variablen Lastbedingungen sowie beim Einsatz technischer Thermoplaste wirkt sich die Kontakttemperatur negativ auf die Leistungsfähigkeit des Systems aus. Die gezielte Nutzung chemischer Umwandlungsprozesse durch Einbringung reaktiver Füllstoffe wie Magnesiumhydroxid verspricht Abhilfe. Die Arbeit befasst sich mit dem Einfluss dieses Füllstoffes auf die werkstofflichen Eigenschaften eines Polyamid 66 und beleuchtet durch umfassende tribologische und oberflächenanalytische Methoden dessen grundlegende Wirkmechanismen. So konnte eine durch Reibungswärme induzierte Umwandlung bestätigt werden, die jedoch eine Schwachstelle im niedrigen Lastbereich aufgrund eines kurzzeitig ungünstigen Zusammenspiels tribochemischer und abrasiver Effekte hervorruft. Im Vergleich zu einer ungefüllten Referenz und zwei Kontrollmaterialien wird insgesamt eine deutliche und über ein großes Lastspektrum stabile Leistungssteigerung erreicht, wobei die Wirkung der Reaktionspartikel durch das Verhindern von Schäden an den integrierten Fasern sowie durch einen reaktionsumsatzabhängigen Vernarbungseffekt hervorsticht. Die Nutzung von Stoffen wie Magnesiumhydroxid stellt einen neuen Ansatz für die Polymertribologie dar und könnte zukünftig intelligente Werkstoffe hervorbringen, die durch lastabhängige Beeinflussung des tribologischen Kontakts dynamisch auf veränderliche Umgebungsbedingungen reagieren.

Beamforming performs spatial filtering to preserve the signal from given directions of interest while suppressing interfering signals and noise arriving from other directions. For example, a microphone array equipped with beamforming algorithm could preserve the sound coming from a target speaker and suppress sounds coming from other speakers. Beamformer has been widely used in many applications such as radar, sonar, communication, and acoustic systems. A data-independent beamformer is the beamformer whose coefficients are independent on sensor signals, it normally uses less computation since the coefficients are computed once. Moreover, its coefficients are derived from the well-defined statistical models, then it produces less artifacts. The major drawback of this beamforming class is its limitation to the interference suppression. On the other hand, an adaptive beamformer is a beamformer whose coefficients depend on or adapt to sensor signals. It is capable of suppressing the interference better than a data-independent beamforming but it suffers from either too much distortion of the signal of interest or less noise reduction when the updating rate of coefficients does not synchronize with the changing rate of the noise model. Besides, it is computationally intensive since the coefficients need to be updated frequently. In acoustic applications, the bandwidth of signals of interest extends over several octaves, but we always expect that the characteristic of the beamformer is invariant with regard to the bandwidth of interest. This can be achieved by the so-called broadband beamforming. Since the beam pattern of conventional beamformers depends on the frequency of the signal, it is common to use a dense and uniform array for the broadband beamforming to guarantee some essential performances together, such as frequency-independence, less sensitive to white noise, high directivity factor or high front-to-back ratio. In this dissertation, we mainly focus on the sparse array of which the aim is to use fewer sensors in the array, while simultaneously assuring several important performances of the beamformer. In the past few decades, many design methodologies for sparse arrays have been proposed and were applied in a variety of practical applications. Although good results were presented, there are still some restrictions, such as the number of sensors is large, the designed beam pattern must be fixed, the steering ability is limited and the computational complexity is high. In this work, two novel approaches for the sparse array design taking a hypothesized uniform array as a basis are proposed, that is, one for data-independent beamformers and the another for adaptive beamformers. As an underlying component of the proposed methods, the dissertation introduces some new insights into the uniform array with broadband beamforming. In this context, a function formulating the relations between the sensor coefficients and its beam pattern over frequency is proposed. The function mainly contains the coordinate transform and inverse Fourier transform. Furthermore, from the bijection of the function and broadband beamforming perspective, we propose the lower and upper bounds for the inter-distance of sensors. Within these bounds, the function is a bijective function that can be utilized to design the uniform array with broadband beamforming. For data-independent beamforming, many studies have focused on optimization procedures to seek the sparse array deployment. This dissertation presents an alternative approach to determine the location of sensors. Starting with a weight spectrum of a virtual dense and uniform array, some techniques are used, such as analyzing a weight spectrum to determine the critical sensors, applying the clustering technique to group the sensors into different groups and selecting representative sensors for each group. After the sparse array deployment is specified, the optimization technique is applied to find the beamformer coefficients. The proposed method helps to save the computation time in the design phase and its beamformer performance outperforms other state-of-the-art methods in several aspects such as the higher white noise gain, higher directivity factor or more frequency-independence. For adaptive beamforming, the dissertation attempts to design a versatile sparse microphone array that can be used for different beam patterns. Furthermore, we aim to reduce the number of microphones in the sparse array while ensuring that its performance can continue to compete with a highly dense and uniform array in terms of broadband beamforming. An irregular microphone array in a planar surface with the maximum number of distinct distances between the microphones is proposed. It is demonstrated that the irregular microphone array is well-suited to sparse recovery algorithms that are used to solve underdetermined systems with subject to sparse solutions. Here, a sparse solution is the sound source's spatial spectrum that need to be reconstructed from microphone signals. From the reconstructed sound sources, a method for array interpolation is presented to obtain an interpolated dense and uniform microphone array that performs well with broadband beamforming. In addition, two alternative approaches for generalized sidelobe canceler (GSC) beamformer are proposed. One is the data-independent beamforming variant, the other is the adaptive beamforming variant. The GSC decomposes beamforming into two paths: The upper path is to preserve the desired signal, the lower path is to suppress the desired signal. From a beam pattern viewpoint, we propose an improvement for GSC, that is, instead of using the blocking matrix in the lower path to suppress the desired signal, we design a beamformer that contains the nulls at the look direction and at some other directions. Both approaches are simple beamforming design methods and they can be applied to either sparse array or uniform array. Lastly, a new technique for direction-of-arrival (DOA) estimation based on the annihilating filter is also presented in this dissertation. It is based on the idea of finite rate of innovation to reconstruct the stream of Diracs, that is, identifying an annihilating filter/locator filter for a few uniform samples and the position of the Diracs are then related to the roots of the filter. Here, an annihilating filter is the filter that suppresses the signal, since its coefficient vector is always orthogonal to every frame of signal. In the DOA context, we regard an active source as a Dirac associated with the arrival direction, then the directions of active sources can be derived from the roots of the annihilating filter. However, the DOA obtained by this method is sensitive to noise and the number of DOAs is limited. To address these issues, the dissertation proposes a robust method to design the annihilating filter and to increase the degree-of-freedom of the measurement system (more active sources can be detected) via observing multiple data frames. Furthermore, we also analyze the performance of DOA with diffuse noise and propose an extended multiple signal classification algorithm that takes diffuse noise into account. In the simulation, it shows, that in the case of diffuse noise, only the extended multiple signal classification algorithm can estimate the DOAs properly.

α-Diimine haben die Fähigkeit starke sigma-Donorbindungen aufzubauen und gleichzeitig als π-Akzeptoren zu fungieren. Damit können sie an eine große Anzahl an Übergangsmetallzentren koordinieren. Durch Funktionalisierung mit einer Phosphanoxid oder -sulfidgruppe können flexible hemilabile Liganden synthetisiert werden, die die Kombination harten und weichen Donorfunktionen vereint. Gepaart mit unterschiedlichen Liganden-Rückgraten, haben diese Liganden die strukturelle Eigenschaft, zwei Metalle in unmittelbarer Nähe koordinieren zu können. In dieser Arbeit werden die Bindungseigenschaften dieser Metalle an bekannten, katalytisch aktiven Übergangsmetallzentren analysiert und verglichen. Die Liganden, 1,4-Bis(2-diphenyl-(thio))phosphorylphenyl)-1,4-diaza-2,3-dimethyl-1,3-butadien (dab-O/S) und [N,N‘-1,2-Acenaphthylenediyliden(2-diphenyl(thio-)phosphorylphenylamin (bian-O/S) können in einer zweistufigen Templatsynthese aus den Edukten 2-Aminophenylendiphenylphosphanoxid oder -sulfid in guten Ausbeuten synthetisiert werden. Sie koordinieren an einwertiges Kupfer in einer tetraedrischen Koordinationsumgebung deren stark verdrehte und schaukelnde Verzerrung durch die τ4- und θx,y,z-Winkelparameter klassifiziert wurde. Mit zweiwertigem Platin gelang die Synthese von monometallischen dab-O- und bian-O-Komplexen und bimetallischen Komplexen mit Zink(II) als zusätzlichen Metall. Durch 195 Pt-NMR-Spektroskopie konnte gezeigt werden, dass trotz der höheren Lewisacidität von Zink(II) die Elektronendichte am Platinzentrum erhöht wird. Mit Ruthenium(II) konnten je nach Zugabe eines schwach koordinierenden Anions monometallische Komplexe oder homobimetallische Komplexe synthetisiert werden. Weiterhin konnten Iridium(III), Rhodium(I) und Nickel(II) Komplexe mit den dab-O und bian-O und bian-S Liganden synthetisiert werden. Die Verbindungen wurden neben den gängigen Verfahren auch cyclovoltammetrisch, spektroelektrochemisch und durch DFT-Rechnungen untersucht.

The present thesis investigates the interaction of size selected transition metal cluster cations with \(N_2\) adsorbate molecules under cryogenic conditions. A tandem cryo ion trap mass spectrometer facilitates the recording of the adsorption kinetics of gases onto size selected transition metals clusters under isothermal cryo conditions. The combination with a tunable OPO/OPA laser system allows for the recording of Infrared-(Multiple) Photodissociation (IR-(M)PD) spectra of the resulting cluster adsorbate complexes. The comparison of the experimental results with DFT modelling allows for structural assignments and the evaluation of the clusters’ electronic properties. We apply the combination of these methods on rhodium, rhodium-iron alloy and tantalum clusters and present the results in seven research studies. The IR-(M)PD spectra of rhodium cluster adsorbate complexes indicate co-existing isomers and a spin quench with increasing number of adsorbed \(N_2\). Adsorption kinetics allowed to assign clusters with rough and smooth surfaces and to find features of adsorption reluctance. Calculated spin valley curves reveal a spin quench upon \(N_2\) adsorption onto the \(Rh_5^+\) cluster. Band shifts in the IR-(M)PD spectra of sequential \(N_2\) adsorption onto the \(Rh_6^+\) cluster are interpreted in terms of adsorbate induced charge dilution, which is supported by DFT calculations. Our combined approach reveals alloy like mixed rhodium iron clusters with adsorption site dependent \(N_2\) stretching vibrations, where \(N_2\) preferentially adsorbs onto rhodium sites. The \(Ta_4^+\) cluster facilitates the cleavage of the initial two \(N_2\) adsorbate molecules. By help of IR-(M)PD spectroscopy and DFT modelling we are able to assign a novel AEAS (across edge-above surface) mechanism and to assign an activated side-on intermediate of the third adsorbate molecule. The investigation sequential \(N_2\) adsorption onto the \(Ta_5^+\) cluster does not reveal any evidence for \(N_2\) activation. DFT modelling reveals low spin states.

We introduce Property-Driven Design, a tool-flow that guarantees formal soundness be- tween ESL and RTL and thus enables a shift-left of general functional verification by moving HW verification to higher abstraction layers. In addition, by generating a formal Verification IP (VIP) automatically from ESL descriptions, the entry hurdle to formal methods is reduced considerably, opening them to a wider audience, which effectively ‘democratizes’ them. Short feedback cycles reduce time spent on RTL verification and lead to higher-quality designs.

Im Rahmen dieser Arbeit wurden Liganden des Typs 2-(2‘-Pyridinyl)pyrimidin untersucht, funktionalisiert und in Folgereaktionen eingesetzt. Dabei wurden verschiedene Substituenten in 4- und 6-Position der Pyridineinheit eingeführt, sowie die daraus resultierenden Liganden mit verschiedenen Metallen insbesondere Iridium und Palladium umgesetzt. Erhaltene N,N-koordinierte Komplexe konnten in der Gasphase hinsichtlich ihrer Aktivierungsbarriere für eine sogenannte roll-over Cyclometallierung untersucht werden. Mit Hilfe der Ergebnisse dieser Untersuchungen konnte identifiziert werden konnte, dass stark elektronenschiebende Substituenten den roll-over Prozess erleichtern. Die Schlussfolgerungen der Voruntersuchungen konnten anschließend in die Praxis umgesetzt werden und in der Folge stabile roll-over cyclometallierte Iridium(III)komplexe in Lösung erhalten werden. Diese C,N-koordinierten Komplexe wurden in Folgereaktionen intensiv weitererforscht. Beispielsweise wurden mehrere bimetallische Komplexe synthetisiert, charakterisiert und für den Einsatz in Katalyse und Photochemie untersucht. Neben den Umsetzungen der Liganden mit Iridium(III), zeigte ein Palladium(II)komplex äußert interessante Eigenschaften. Beim Vergleich mit ähnlichen Liganden, die unter den gleichen Bedingungen umgesetzt wurden, konnte beim erwähnten Komplex ein deutlicher Unterschied der Bindung zwischen Palladium(II)zentrum und Ligand festgestellt werden. Während andere Komplexe ebenfalls eine roll-over Cyclometallierung durchlaufen, wird beim genannten Komplex ein sp3-hybridisiertes Wasserstoffatom substituiert und eine C,N,N-Koordination erhalten. Die Schlussfolgerungen aus beiden Bereichen brachten die interessante Erkenntnis, dass für den untersuchten Typ Ligand die benötigte Elektronendichte innerhalb eines engen Fensters liegen muss, was die Entwicklung eines Pyrimidinylpyrimidinliganden zur Folge hatte. In einem gesonderten Teilbereich wurden außerdem Platin(II)komplexe für die Etablierung einer stopped-flow Messzelle an der Technischen Universität Kaiserslautern entwickelt. Dazu wurde die sehr elektronenreiche Vorstufe Bis(dimethylsulfoxid)dimethylplatin(II) mit einer Reihe verschieden konfigurierter Bipyridine umgesetzt. Die erhaltenen Komplexe wurden durch den Arbeitskreis Gerhards der physikalischen Chemie mit Acetylchlorid zur Reaktion gebracht und die unterschiedlichen Reaktionsgeschwindigkeiten IR-spektroskopisch untersucht.

Die realkalisierende Wirkung von mineralischen Mörteln ist aus der Instandsetzung von carbonatisierten Betonen im Hochbau bekannt. Die Anwendungsgrenzen beziehen sich dabei entsprechend der DAfStb-Richtlinie „Schutz und Instandsetzung von Betonbauteilen“ auf die Verwendung eines Portlandzement basierten (CEM I) Instandsetzungsmaterials sowie darauf, dass die mittlere carbonatisierungstiefe um nicht mehr als 20 mm hinter die Bewehrung vorgedrungen ist. Bei der Instandsetzung von Trinkwasserbehältern wird die Realkalisierung von mineralischen Beschichtungen ebenfalls bei der Anwendung der Auskleidungsprinzipien unter Berücksichtigung zusätzlicher technischer und hygienischer Randbedingungen zugrunde gelegt. Für die Anwendung in Trinkwasserbehältern wird das Realkalisierungsdepot mineralischer Beschichtungen zwar als Fähigkeit zur Erhöhung der Alkalität des Altbetons definiert, jedoch fehlen bisher hinreichende wissenschaftliche Erkenntnisse, damit die Realkalisierung für Anwender und Planer im Trinkwasserbereich fassbar und abschätzbar wird. Unter Berücksichtigung der maßgebenden Einflussgrößen werden in dieser Arbeit die Mechanismen der Realkalisierung anhand experimenteller Untersuchungen abgeleitet und erläutert. Das Realkalisierungsvermögen von Instandsetzungsmörteln wird näher spezifiziert, sodass es dem Anwender ermöglicht wird, Mörtelsysteme auszuwählen, die für das jeweilige Auskleidungsprinzip angewendet werden können. Da der Realkalisierungsfortschritt unter Berücksichtigung der Einflussgrößen bisher nicht berechnet werden kann, wird auf Grundlage der experimentellen Untersuchungen ein vereinfachtes Berechnungsmodell zur Beschreibung der Realkalisierung entwickelt. Anhand von theoretischen Simulationen wird abschließend das Modell validiert.

The semantics of programming languages assign a meaning to the written program syntax. Currently, the meaning of synchronous programming languages, which are especially designed to develop programs for reactive and embedded systems, is based on a formal semantics definition similar to Fitting`s fixpoint semantics for logic programs. Nevertheless, it is possible to write a synchronous program code that does not evaluate to concrete values with the current semantics, which means those programs are currently seen to be not constructive. In the last decades, the theoretical knowledge and representation of semantics for logic programming has increased, but not all theoretical results and achievements have found their way to practice and application in system design. This thesis, in a first part, focuses on extensions to the semantics of synchronous programming languages to an evaluation similar to a well-founded semantics as defined in logic programming by van Gelder, Ross and Schlipf and to the stable model semantics as defined by Gelfond and Lifschitz. Particularly, this allows an evaluation for some of the currently not constructive programs where the semantics based on Fitting`s fixpoint fails. It is shown that the extension to well-founded semantics is a conservative extension of Fitting`s semantics, so that the meaning for programs which were already constructive does not change. Finally, it is considered how one can still generate circuits that implement the considered synchronous programs with the well-founded semantics. Again, this is a conservative approach that does not modify the circuits generated by the so-far used synthesis procedures. Answer set programming and the underlying stable model semantics describe problems by constraints and the related answer set solvers give all solutions to that problem as so-called answers. This allows the formulation of searching and planning problems as well as efficient solutions without having the need to develop special and possibly error-prone algorithms for every single application. The semantics of the synchronous programming language Quartz is also extended to the stable model semantics. For this extension, two alternatives are discussed: First of all, a direct extension similar to the extension to well-founded semantics is discussed. Second, a transformation of synchronous programs to the available answer set programming languages is given, as this allows to directly use answer set solvers for the synthesis and optimization of synchronous systems. The second part of the thesis contains further examples of the use of answer set programming in system design to emphasis their benefits for system design in general. The first example is hereby the generation of optimal/minimal interconnection-networks which allow non-blocking connections between n sources and n targets in parallel. As a second example, the stable model semantics is used to build a complete compiler chain, which transforms a given program to an optimal assembler code (called move code) for the new SCAD processor architecture which was developed at the University of Kaiserslautern. As a final part, the lessons learned from the two examples are shown by the means of some enhancement ideas for the synchronous programming language paradigm.