With the burgeoning computing power available, multiscale modelling and simulation has these days become increasingly capable of capturing the details of physical processes on different scales. The mechanical behavior of solids is oftentimes the result of interaction between multiple spatial and temporal scales at different levels and hence it is a typical phenomena of interest exhibiting multiscale characteristic. At the most basic level, properties of solids can be attributed to atomic interactions and crystal structure that can be described on nano scale. Mechanical properties at the macro scale are modeled using continuum mechanics for which we mention stresses and strains. Continuum models, however they offer an efficient way of studying material properties they are not accurate enough and lack microstructural information behind the microscopic mechanics that cause the material to behave in a way it does. Atomistic models are concerned with phenomenon at the level of lattice thereby allowing investigation of detailed crystalline and defect structures, and yet the length scales of interest are inevitably far beyond the reach of full atomistic computation and is rohibitively expensive. This makes it necessary the need for multiscale models. The bottom line and a possible avenue to this end is, coupling different length scales, the continuum and the atomistics in accordance with standard procedures. This is done by recourse to the Cauchy-Born rule and in so doing, we aim at a model that is efficient and reasonably accurate in mimicking physical behaviors observed in nature or laboratory. In this work, we focus on concurrent coupling based on energetic formulations that links the continuum to atomistics. At the atomic scale, we describe deformation of the solid by the displaced positions of atoms that make up the solid and at the continuum level deformation of the solid is described by the displacement field that minimize the total energy. In the coupled model, continuum-atomistic, a continuum formulation is retained as the overall framework of the problem and the atomistic feature is introduced by way of constitutive description, with the Cauchy-Born rule establishing the point of contact. The entire formulation is made in the framework of nonlinear elasticity and all the simulations are carried out within the confines of quasistatic settings. The model gives direct account to measurable features of microstructures developed by crystals through sequential lamination.

A new and systematic approach to machine vision-based robot manipulation of deformable (non-rigid) linear objects is introduced. This approach reduces the computational needs by using a simple state-oriented model of the objects. These states describe the relation of the object with respect to an obstacle and are derived from the object image and its features. Therefore, the object is segmented from a standard video frame using a fast segmentation algorithm. Several object features are presented which allow the state recognition of the object while being manipulated by the robot.

A geoscientifically relevant wavelet approach is established for the classical (inner) displacement problem corresponding to a regular surface (such as sphere, ellipsoid, actual earth's surface). Basic tools are the limit and jump relations of (linear) elastostatics. Scaling functions and wavelets are formulated within the framework of the vectorial Cauchy-Navier equation. Based on appropriate numerical integration rules a pyramid scheme is developed providing fast wavelet transform (FWT). Finally multiscale deformation analysis is investigated numerically for the case of a spherical boundary.

In this work the investigation of a (Ti, Al, Si) N system was done. The main point of investigation was to study the possibility of getting the nanocomposite coatings structures by deposition of multilayer films from TiN, AlSiN, . This tries to understand the relation between the mechanical properties (hardness, Young s modulus), and the microstructure (nanocrystalline with individual phases). Particularly special attention was given to the temperature effects on microstructural changes in annealing at 600 °C for the coatings. The surface hardness, elastic modulus, and the multilayers diffusion and compositions were the test tools for the comparison between the different coated samples with and without annealing at 600 °C. To achieve this object a rectangular aluminum vacuum chamber with three unbalanced sputtering magnetrons for the deposition of thin film coatings from different materials was constructed The chamber consists mainly of two chambers, the pre-vacuum chamber to load the workpiece, and the main vacuum chamber where the sputtering deposition of the thin film coatings take place. The workpiece is moving on a car travel on a railway between the two chambers to the position of the magnetrons by step motors. The chambers are divided by a self constructed rectangular gate controlled manually from outside the chamber. The chamber was sealed for vacuum use using glue and screws. Therefore, different types of glue were tested not only for its ability to develop an uniform thin layer in the gap between the aluminum plates to seal the chamber for vacuum use, but also low outgassing rates which made it suitable for vacuum use. A epoxy was able to fulfill this tasks. The evacuation characteristics of the constructed chamber was improved by minimizing the inner surface outgassing rate. Therefore, the throughput outgassing rate test method was used in the comparisons between the selected two aluminum materials (A2017 and A5353) samples short time period (one hour) outgassing rates. Different machining methods and treatments for the inner surface of the vacuum chamber were tested. The machining of the surface of material A (A2017) with ethanol as coolant fluid was able to reduce its outgassing rate a factor of 6 compared with a non-machined sample surface of the same material. The reduction of the surface porous oxide layer on the top of the aluminum surface by the pickling process with HNO3 acid, and the protection of it by producing another passive non-porous oxides layer using anodizing process will protect the surface for longer time and will minimize the outgassing rates even under humid atmosphere The residual gas analyzer (RGA) 6. Summary test shows that more than 85% of the gases inside the test chamber were water vapour (H2O) and the rests are (N2, H2, CO), so liquid nitrogen water vapor trap can enhance the chamber pumping down process. As a result it was possible to construct a chamber that can be pumped down using a turbo molecular pump (450 L/s) to the range of 1x10-6 mbar within one hour of evacuations where the chamber volume is 160 Litters and the inner surface area is 1.6 m2. This is a good base pressure for the process of sputtering deposition of hard thin film coatings. Multilayer thin film coating was deposited to demonstrate that nanostructured thin film within the (Ti, Al, Si) N system could be prepared by reactive magnetron sputtering of multi thin film layers of TiN, AlSiN. The (SNMS) spectrometry of the test samples show that a complete diffusion between the different deposited thin film coating layers in each sample takes place, even at low substrate deposition temperature. The high magnetic flux of the unbalanced magnetrons and the high sputtering power were able to produce a high ion-toatom flux, which give high mobility to the coated atoms. The interactions between the high mobility of the coated atoms and the ion-to-atom flux were sufficient to enhance the diffusion between the different deposited thin layers. It was shown from the XRD patterns for this system that the structure of the formed mixture consists of two phases. One phase is noted as TiN bulk and another detected unknown amorphous phase, which can be SiNx or AlN or a combination of Ti-Al-Si-N. As a result we where able to deposit a nanocomposite coatings by the deposition of multilayers from TiN, AlSiN thin film coatings using the constructed vacuum chamber

Recently, many online social networks, such as MySpace, Orkut, and Friendster, have faced inactivity decay of their members, which contributed to the collapse of these networks. The reasons, mechanics, and prevention mechanisms of such inactivity decay are not fully understood. In this work, we analyze decayed and alive subwebsites from the Stack Exchange platform. The analysis mainly focuses on the inactivity cascades that occur among the members of these communities. We provide measures to understand the decay process and statistical analysis to extract the patterns that accompany the inactivity decay. Additionally, we predict cascade size and cascade virality using machine learning. The results of this work include a statistically significant difference of the decay patterns between the decayed and the alive subwebsites. These patterns are mainly cascade size, cascade virality, cascade duration, and cascade similarity. Additionally, the contributed prediction framework showed satisfactorily prediction results compared to a baseline predictor. Supported by empirical evidence, the main findings of this work are (1) there are significantly different decay patterns in the alive and the decayed subwebsites of the Stack Exchange; (2) the cascade’s node degrees contribute more to the decay process than the cascade’s virality, which indicates that the expert members of the Stack Exchange subwebsites were mainly responsible for the activity or inactivity of the Stack Exchange subwebsites; (3) the Statistics subwebsite is going through decay dynamics that may lead to it becoming fully-decayed; (4) the decay process is not governed by only one network measure, it is better described using multiple measures; (5) decayed subwebsites were originally less resilient to inactivity decay, unlike the alive subwebsites; and (6) network’s structure in the early stages of its evolution dictates the activity/inactivity characteristics of the network.

Building interoperation among separately developed software units requires checking their conceptual assumptions and constraints. However, eliciting such assumptions and constraints is time consuming and is a challenging task as it requires analyzing each of the interoperating software units. To address this issue we proposed a new conceptual interoperability analysis approach which aims at decreasing the analysis cost and the conceptual mismatches between the interoperating software units. In this report we present the design of a planned controlled experiment for evaluating the effectiveness, efficiency, and acceptance of our proposed conceptual interoperability analysis approach. The design includes the study objectives, research questions, statistical hypotheses, and experimental design. It also provides the materials that will be used in the execution phase of the planned experiment.

In the literature, there are at least two equivalent two-factor Gaussian models for the instantaneous short rate. These are the original two-factor Hull White model (see [3]) and the G2++ one by Brigo and Mercurio (see [1]). Both these models first specify a time homogeneous two-factor short rate dynamics and then by adding a deterministic shift function '(·) fit exactly the initial term structure of interest rates. However, the obtained results are rather clumsy and not intuitive which means that a special care has to be taken for their correct numerical implementation.

Anwendung neuronaler Netze in der Finanzwirtschaft

In der vorliegenden Arbeit wird das Tragverhalten von durchlaufenden stahlfaserbewehrten Stahlverbunddecken analysiert. Auf der Basis von experimentellen und rechnerischen Untersuchungen werden zwei Bemessungsmodelle entwickelt. Anhand der experimentellen Untersuchungen an einfeldrigen und durchlaufenden stahlfaserbewehrten Verbunddecken werden Aufschlüsse über das Trag- und Verformungsverhalten der Decken gewonnen. Dabei werden sowohl offene trapezförmige als auch hinterschnittene Profilbleche verwendet. Auf eine konventionelle Betonstahlbewehrung wird gänzlich verzichtet. Das Stützmoment wird vom Stahlfaserbeton alleine aufgenommen. In vier Versuchsserien mit insgesamt 18 Versuchen werden einzelne Parameter wie z. B. unterschiedliche Deckenstärken, unterschiedliche Profilblechgeometrien sowie unterschiedliche Stahlfaserbetonmischungen untersucht. Für die Berechnung und Bemessung werden die im Verbundbau üblichen Nachweisverfahren aufgegriffen und modifiziert. Die Traganteile des Stahlfaserbetons werden über den Ansatz von Spannungsblöcken implementiert. Bei der Nachrechnung der einzelnen Versuche zeigt sich die Eignung der Verfahren. Für die einzelnen Nachweise werden in Parameterstudien Bemessungsdiagramme und –tabellen erstellt, die dem anwendenden Ingenieur ein einfaches und sicheres Bemessen ermöglichen. Anhand der experimentellen Ergebnisse und der rechnerischen Untersuchungen werden zwei mögliche Bemessungsmodelle entwickelt, mit denen die Tragfähigkeit von stahlfaserbewehrten durchlaufenden Verbunddecken nachgewiesen werden kann. Dabei kann der Nachweis entweder nach den Verfahren Elastisch-Plastisch oder Plastisch-Plastisch erfolgen.

In 2006 Jeffrey Achter proved that the distribution of divisor class groups of degree 0 of function fields with a fixed genus and the distribution of eigenspaces in symplectic similitude groups are closely related to each other. Gunter Malle proposed that there should be a similar correspondence between the distribution of class groups of number fields and the distribution of eigenspaces in ceratin matrix groups. Motivated by these results and suggestions we study the distribution of eigenspaces corresponding to the eigenvalue one in some special subgroups of the general linear group over factor rings of rings of integers of number fields and derive some conjectural statements about the distribution of \(p\)-parts of class groups of number fields over a base field \(K_{0}\). Where our main interest lies in the case that \(K_{0}\) contains the \(p\)th roots of unity, because in this situation the \(p\)-parts of class groups seem to behave in an other way like predicted by the popular conjectures of Henri Cohen and Jacques Martinet. In 2010 based on computational data Malle has succeeded in formulating a conjecture in the spirit of Cohen and Martinet for this case. Here using our investigations about the distribution in matrixgroups we generalize the conjecture of Malle to a more abstract level and establish a theoretical backup for these statements.

Dealing with information in modern times involves users to cope with hundreds of thousands of documents, such as articles, emails, Web pages, or News feeds. Above all information sources, the World Wide Web presents information seekers with great challenges. It offers more text in natural language than one is capable to read. The key idea for this research intends to provide users with adaptable filtering techniques, supporting them in filtering out the specific information items they need. Its realization focuses on developing an Information Extraction system, which adapts to a domain of concern, by interpreting the contained formalized knowledge. Utilizing the Resource Description Framework (RDF), which is the Semantic Web's formal language for exchanging information, allows extending information extractors to incorporate the given domain knowledge. Because of this, formal information items from the RDF source can be recognized in the text. The application of RDF allows a further investigation of operations on recognized information items, such as disambiguating and rating the relevance of these. Switching between different RDF sources allows changing the application scope of the Information Extraction system from one domain of concern to another. An RDF-based Information Extraction system can be triggered to extract specific kinds of information entities by providing it with formal RDF queries in terms of the SPARQL query language. Representing extracted information in RDF extends the coverage of the Semantic Web's information degree and provides a formal view on a text from the perspective of the RDF source. In detail, this work presents the extension of existing Information Extraction approaches by incorporating the graph-based nature of RDF. Hereby, the pre-processing of RDF sources allows extracting statistical information models dedicated to support specific information extractors. These information extractors refine standard extraction tasks, such as the Named Entity Recognition, by using the information provided by the pre-processed models. The post-processing of extracted information items enables representing these results in RDF format or lists, which can now be ranked or filtered by relevance. Post-processing also comprises the enrichment of originating natural language text sources with extracted information items by using annotations in RDFa format. The results of this research extend the state-of-the-art of the Semantic Web. This work contributes approaches for computing customizable and adaptable RDF views on the natural language content of Web pages. Finally, due to the formal nature of RDF, machines can interpret these views allowing developers to process the contained information in a variety of applications.

Both theoretical and experimental results for the dynamics of photoexcited electrons at surfaces of Cu and the ferromagnetic transition metals Fe, Co, and Ni are presented. A model for the dynamics of excited electrons is developed, which is based on the Boltzmann equation and includes effects of photoexcitation, electron-electron scattering, secondary electrons (cascade and Auger electrons), and transport of excited carriers out of the detection region. From this we determine the time-resolved two-photon photoemission (TR-2PPE). Thus a direct comparison of calculated relaxation times with experimental results by means of TR-2PPE becomes possible. The comparison indicates that the magnitudes of the spin-averaged relaxation time t and of the ratio t_up/t_down of majority and minority relaxation times for the different ferromagnetic transition metals result not only from density-of-states effects, but also from different Coulomb matrix elements M. Taking M_Fe > M_Cu > M_Ni = M_Co we get reasonable agreement with experiments.

Abstract The main theme of this thesis is about Graph Coloring Applications and Defining Sets in Graph Theory. As in the case of block designs, finding defining sets seems to be difficult problem, and there is not a general conclusion. Hence we confine us here to some special types of graphs like bipartite graphs, complete graphs, etc. In this work, four new concepts of defining sets are introduced: • Defining sets for perfect (maximum) matchings • Defining sets for independent sets • Defining sets for edge colorings • Defining set for maximal (maximum) clique Furthermore, some algorithms to find and construct the defining sets are introduced. A review on some known kinds of defining sets in graph theory is also incorporated, in chapter 2 the basic definitions and some relevant notations used in this work are introduced. chapter 3 discusses the maximum and perfect matchings and a new concept for a defining set for perfect matching. Different kinds of graph colorings and their applications are the subject of chapter 4. Chapter 5 deals with defining sets in graph coloring. New results are discussed along with already existing research results, an algorithm is introduced, which enables to determine a defining set of a graph coloring. In chapter 6, cliques are discussed. An algorithm for the determination of cliques using their defining sets. Several examples are included.

Hydrogels are known to be covalently or ionic cross-linked, hydrophilic three-dimensional polymer networks, which exist in our bodies in a biological gel form such as the vitreous humour that fills the interior of the eyes. Poly(N-isopropylacrylamide) (poly(NIPAAm)) hydrogels are attracting more interest in biomedical applications because, besides others, they exhibit a well-defined lower critical solution temperature (LCST) in water, around 31–34°C, which is close to the body temperature. This is considered to be of great interest in drug delivery, cell encapsulation, and tissue engineering applications. In this work, the poly(NIPAAm) hydrogel is synthesized by free radical polymerization. Hydrogel properties and the dimensional changes accompanied with the volume phase transition of the thermosensitive poly(NIPAAm) hydrogel were investigated in terms of Raman spectra, swelling ratio, and hydration. The thermal swelling/deswelling changes that occur at different equilibrium temperatures and different solutions (phenol, ethanol, propanol, and sodium chloride) based on Raman spectrum were investigated. In addition, Raman spectroscopy has been employed to evaluate the diffusion aspects of bovine serum albumin (BSA) and phenol through the poly(NIPAAm) network. The determination of the mutual diffusion coefficient, \(D_{mut}\) for hydrogels/solvent system was achieved successfully using Raman spectroscopy at different solute concentrations. Moreover, the mechanical properties of the hydrogel, which were investigated by uniaxial compression tests, were used to characterize the hydrogel and to determine the collective diffusion coefficient through the hydrogel. The solute release coupled with shrinking of the hydrogel particles was modelled with a bi-dimensional diffusion model with moving boundary conditions. The influence of the variable diffusion coefficient is observed and leads to a better description of the kinetic curve in the case of important deformation around the LCST. A good accordance between experimental and calculated data was obtained.

This thesis presents a novel, generic framework for information segmentation in document images. A document image contains different types of information, for instance, text (machine printed/handwritten), graphics, signatures, and stamps. It is necessary to segment information in documents so that to process such segmented information only when required in automatic document processing workflows. The main contribution of this thesis is the conceptualization and implementation of an information segmentation framework that is based on part-based features. The generic nature of the presented framework makes it applicable to a variety of documents (technical drawings, magazines, administrative, scientific, and academic documents) digitized using different methods (scanners, RGB cameras, and hyper-spectral imaging (HSI) devices). A highlight of the presented framework is that it does not require large training sets, rather a few training samples (for instance, four pages) lead to high performance, i.e., better than previously existing methods. In addition, the presented framework is simple and can be adapted quickly to new problem domains. This thesis is divided into three major parts on the basis of document digitization method (scanned, hyper-spectral imaging, and camera captured) used. In the area of scanned document images, three specific contributions have been realized. The first of them is in the domain of signature segmentation in administrative documents. In some workflows, it is very important to check the document authenticity before processing the actual content. This can be done based on the available seal of authenticity, e.g., signatures. However, signature verification systems expect pre-segmented signature image, while signatures are usually a part of document. To use signature verification systems on document images, it is necessary to first segment signatures in documents. This thesis shows that the presented framework can be used to segment signatures in administrative documents. The system based on the presented framework is tested on a publicly available dataset where it outperforms the state-of-the-art methods and successfully segmented all signatures, while less than half of the found signatures are false positives. This shows that it can be applied for practical use. The second contribution in the area of scanned document images is segmentation of stamps in administrative documents. A stamp also serves as a seal for documents authenticity. However, the location of stamp on the document can be more arbitrary than a signature depending on the person sealing the document. This thesis shows that a system based on our generic framework is able to extract stamps of any arbitrary shape and color. The evaluation of the presented system on a publicly available dataset shows that it is also able to segment black stamps (that were not addressed in the past) with a recall and precision of 83% and 73%, respectively. %Furthermore, to segment colored stamps, this thesis presents a novel feature set which is based on intensity gradient, is able to extract unseen, colored, arbitrary shaped, textual as well as graphical stamps, and outperforms the state-of-the-art methods. The third contribution in the scanned document images is in the domain of information segmentation in technical drawings (architectural floorplans, maps, circuit diagrams, etc.) containing usually a large amount of graphics and comparatively less textual components. Further, as in technical drawings, text is overlapping with graphics. Thus, automatic analysis of technical drawings uses text/graphics segmentation as a pre-processing step. This thesis presents a method based on our generic information segmentation framework that is able to detect the text, which is touching graphical components in architectural floorplans and maps. Evaluation of the method on a publicly available dataset of architectural floorplans shows that it is able to extract almost all touching text components with precision and recall of 71% and 95%, respectively. This means that almost all of the touching text components are successfully extracted. In the area of hyper-spectral document images, two contributions have been realized. Unlike normal three channels RGB images, hyper-spectral images usually have multiple channels that range from ultraviolet to infrared regions including the visible region. First, this thesis presents a novel automatic method for signature segmentation from hyper-spectral document images (240 spectral bands between 400 - 900 nm). The presented method is based on a part-based key point detection technique, which does not use any structural information, but relies only on the spectral response of the document regardless of ink color and intensity. The presented method is capable of segmenting (overlapping and non-overlapping) signatures from varying backgrounds like, printed text, tables, stamps, logos, etc. Importantly, the presented method can extract signature pixels and not just the bounding boxes. This is substantial when signatures are overlapping with text and/or other objects in image. Second, this thesis presents a new dataset comprising of 300 documents scanned using a high-resolution hyper-spectral scanner. Evaluation of the presented signature segmentation method on this hyper-spectral dataset shows that it is able to extract signature pixels with the precision and recall of 100% and 79%, respectively. Further contributions have been made in the area of camera captured document images. A major problem in the development of Optical Character Recognition (OCR) systems for camera captured document images is the lack of labeled camera captured document images datasets. In the first place, this thesis presents a novel, generic, method for automatic ground truth generation/labeling of document images. The presented method builds large-scale (i.e., millions of images) datasets of labeled camera captured / scanned documents without any human intervention. The method is generic and can be used for automatic ground truth generation of (scanned and/or camera captured) documents in any language, e.g., English, Russian, Arabic, Urdu. The evaluation of the presented method, on two different datasets in English and Russian, shows that 99.98% of the images are correctly labeled in every case. Another important contribution in the area of camera captured document images is the compilation of a large dataset comprising 1 million word images (10 million character images), captured in a real camera-based acquisition environment, along with the word and character level ground truth. The dataset can be used for training as well as testing of character recognition systems for camera-captured documents. Various benchmark tests are performed to analyze the behavior of different open source OCR systems on camera captured document images. Evaluation results show that the existing OCRs, which already get very high accuracies on scanned documents, fail on camera captured document images. Using the presented camera-captured dataset, a novel character recognition system is developed which is based on a variant of recurrent neural networks, i.e., Long Short Term Memory (LSTM) that outperforms all of the existing OCR engines on camera captured document images with an accuracy of more than 95%. Finally, this thesis provides details on various tasks that have been performed in the area closely related to information segmentation. This includes automatic analysis and sketch based retrieval of architectural floor plan images, a novel scheme for online signature verification, and a part-based approach for signature verification. With these contributions, it has been shown that part-based methods can be successfully applied to document image analysis.

The advent of heterogeneous many-core systems has increased the spectrum of achievable performance from multi-threaded programming. As the processor components become more distributed, the cost of synchronization and communication needed to access the shared resources increases. Concurrent linearizable access to shared objects can be prohibitively expensive in a high contention workload. Though there are various mechanisms (e.g., lock-free data structures) to circumvent the synchronization overhead in linearizable objects, it still incurs performance overhead for many concurrent data types. Moreover, many applications do not require linearizable objects and apply ad-hoc techniques to eliminate synchronous atomic updates. In this thesis, we propose the Global-Local View Model. This programming model exploits the heterogeneous access latencies in many-core systems. In this model, each thread maintains different views on the shared object: a thread-local view and a global view. As the thread-local view is not shared, it can be updated without incurring synchronization costs. The local updates become visible to other threads only after the thread-local view is merged with the global view. This scheme improves the performance at the expense of linearizability. Besides the weak operations on the local view, the model also allows strong operations on the global view. Combining operations on the global and the local views, we can build data types with customizable consistency semantics on the spectrum between sequential and purely mergeable data types. Thus the model provides a framework that captures the semantics of Multi-View Data Types. We discuss a formal operational semantics of the model. We also introduce a verification method to verify the correctness of the implementation of several multi-view data types. Frequently, applications require updating shared objects in an “all-or-nothing” manner. Therefore, the mechanisms to synchronize access to individual objects are not sufficient. Software Transactional Memory (STM) is a mechanism that helps the programmer to correctly synchronize access to multiple mutable shared data by serializing the transactional reads and writes. But under high contention, serializable transactions incur frequent aborts and limit parallelism, which can lead to severe performance degradation. Mergeable Transactional Memory (MTM), proposed in this thesis, allows accessing multi-view data types within a transaction. Instead of aborting and re-executing the transaction, MTM merges its changes using the data-type specific merge semantics. Thus it provides a consistency semantics that allows for more scalability even under contention. The evaluation of our prototype implementation in Haskell shows that mergeable transactions outperform serializable transactions even under low contention while providing a structured and type-safe interface.

We present a constructive theory for locally supported approximate identities on the unit ball in \(\mathbb{R}^3\). The uniform convergence of the convolutions of the derived kernels with an arbitrary continuous function \(f\) to \(f\), i.e. the defining property of an approximate identity, is proved. Moreover, an explicit representation for a class of such kernels is given. The original publication is available at www.springerlink.com

The goal of this work is to develop statistical natural language models and processing techniques based on Recurrent Neural Networks (RNN), especially the recently introduced Long Short- Term Memory (LSTM). Due to their adapting and predicting abilities, these methods are more robust, and easier to train than traditional methods, i.e., words list and rule-based models. They improve the output of recognition systems and make them more accessible to users for browsing and reading. These techniques are required, especially for historical books which might take years of effort and huge costs to manually transcribe them. The contributions of this thesis are several new methods which have high-performance computing and accuracy. First, an error model for improving recognition results is designed. As a second contribution, a hyphenation model for difficult transcription for alignment purposes is suggested. Third, a dehyphenation model is used to classify the hyphens in noisy transcription. The fourth contribution is using LSTM networks for normalizing historical orthography. A size normalization alignment is implemented to equal the size of strings, before the training phase. Using the LSTM networks as a language model to improve the recognition results is the fifth contribution. Finally, the sixth contribution is a combination of Weighted Finite-State Transducers (WFSTs), and LSTM applied on multiple recognition systems. These contributions will be elaborated in more detail. Context-dependent confusion rules is a new technique to build an error model for Optical Character Recognition (OCR) corrections. The rules are extracted from the OCR confusions which appear in the recognition outputs and are translated into edit operations, e.g., insertions, deletions, and substitutions using the Levenshtein edit distance algorithm. The edit operations are extracted in a form of rules with respect to the context of the incorrect string to build an error model using WFSTs. The context-dependent rules assist the language model to find the best candidate corrections. They avoid the calculations that occur in searching the language model and they also make the language model able to correct incorrect words by using context- dependent confusion rules. The context-dependent error model is applied on the university of Washington (UWIII) dataset and the Nastaleeq script in Urdu dataset. It improves the OCR results from an error rate of 1.14% to an error rate of 0.68%. It performs better than the state-of-the-art single rule-based which returns an error rate of 1.0%. This thesis describes a new, simple, fast, and accurate system for generating correspondences between real scanned historical books and their transcriptions. The alignment has many challenges, first, the transcriptions might have different modifications, and layout variations than the original book. Second, the recognition of the historical books have misrecognition, and segmentation errors, which make the alignment more difficult especially the line breaks, and pages will not have the same correspondences. Adapted WFSTs are designed to represent the transcription. The WFSTs process Fraktur ligatures and adapt the transcription with a hyphenations model that allows the alignment with respect to the varieties of the hyphenated words in the line breaks of the OCR documents. In this work, several approaches are implemented to be used for the alignment such as: text-segments, page-wise, and book-wise approaches. The approaches are evaluated on German calligraphic (Fraktur) script historical documents dataset from “Wan- derungen durch die Mark Brandenburg” volumes (1862-1889). The text-segmentation approach returns an error rate of 2.33% without using a hyphenation model and an error rate of 2.0% using a hyphenation model. Dehyphenation methods are presented to remove the hyphen from the transcription. They provide the transcription in a readable and reflowable format to be used for alignment purposes. We consider the task as classification problem and classify the hyphens from the given patterns as hyphens for line breaks, combined words, or noise. The methods are applied on clean and noisy transcription for different languages. The Decision Trees classifier returns better performance on UWIII dataset and returns an accuracy of 98%. It returns 97% on Fraktur script. A new method for normalizing historical OCRed text using LSTM is implemented for different texts, ranging from Early New High German 14th - 16th centuries to modern forms in New High German applied on the Luther bible. It performed better than the rule-based word-list approaches. It provides a transcription for various purposes such as part-of-speech tagging and n-grams. Also two new techniques are presented for aligning the OCR results and normalize the size by using adding Character-Epsilons or Appending-Epsilons. They allow deletion and insertion in the appropriate position in the string. In normalizing historical wordforms to modern wordforms, the accuracy of LSTM on seen data is around 94%, while the state-of-the-art combined rule-based method returns 93%. On unseen data, LSTM returns 88% and the combined rule-based method returns 76%. In normalizing modern wordforms to historical wordforms, the LSTM delivers the best performance and returns 93.4% on seen data and 89.17% on unknown data. In this thesis, a deep investigation has been done on constructing high-performance language modeling for improving the recognition systems. A new method to construct a language model using LSTM is designed to correct OCR results. The method is applied on UWIII and Urdu script. The LSTM approach outperforms the state-of-the-art, especially for unseen tokens during training. On the UWIII dataset, the LSTM returns reduction in OCR error rates from 1.14% to 0.48%. On the Nastaleeq script in Urdu dataset, the LSTM reduces the error rate from 6.9% to 1.58%. Finally, the integration of multiple recognition outputs can give higher performance than a single recognition system. Therefore, a new method for combining the results of OCR systems is explored using WFSTs and LSTM. It uses multiple OCR outputs and votes for the best output to improve the OCR results. It performs better than the ISRI tool, Pairwise of Multiple Sequence and it helps to improve the OCR results. The purpose is to provide correct transcription so that it can be used for digitizing books, linguistics purposes, N-grams, and part-of-speech tagging. The method consists of two alignment steps. First, two recognition systems are aligned using WFSTs. The transducers are designed to be more flexible and compatible with the different symbols in line and page breaks to avoid the segmentation and misrecognition errors. The LSTM model then is used to vote the best candidate correction of the two systems and improve the incorrect tokens which are produced during the first alignment. The approaches are evaluated on OCRs output from the English UWIII and historical German Fraktur dataset which are obtained from state-of-the-art OCR systems. The Experiments show that the error rate of ISRI-Voting is 1.45%, the error rate of the Pairwise of Multiple Sequence is 1.32%, the error rate of the Line-to-Page alignment is 1.26% and the error rate of the LSTM approach has the best performance with 0.40%. The purpose of this thesis is to contribute methods providing correct transcriptions corresponding to the original book. This is considered to be the first step towards an accurate and more effective use of the documents in digital libraries.

The Context and Its Importance: In safety and reliability analysis, the information generated by Minimal Cut Set (MCS) analysis is large. The Top Level event (TLE) that is the root of the fault tree (FT) represents a hazardous state of the system being analyzed. MCS analysis helps in analyzing the fault tree (FT) qualitatively-and quantitatively when accompanied with quantitative measures. The information shows the bottlenecks in the fault tree design leading to identifying weaknesses of the system being examined. Safety analysis (containing the MCS analysis) is especially important for critical systems, where harm can be done to the environment or human causing injuries, or even death during the system usage. Minimal Cut Set (MCS) analysis is performed using computers and generating a lot of information. This phase is called MCS analysis I in this thesis. The information is then analyzed by the analysts to determine possible issues and to improve the design of the system regarding its safety as early as possible. This phase is called MCS analysis II in this thesis. The goal of my thesis was developing interactive visualizations to support MCS analysis II of one fault tree (FT). The Methodology: As safety visualization-in this thesis, Minimal Cut Set analysis II visualization-is an emerging field and no complete checklist regarding Minimal Cut Set analysis II requirements and gaps were available from the perspective of visualization and interaction capabilities, I have conducted multiple studies using different methods with different data sources (i.e., triangulation of methods and data) for determining these requirements and gaps before developing and evaluating visualizations and interactions supporting Minimal Cut Set analysis II. Thus, the following approach was taken in my thesis: 1- First, a triangulation of mixed methods and data sources was conducted. 2- Then, four novel interactive visualizations and one novel interaction widget were developed. 3- Finally, these interactive visualizations were evaluated both objectively and subjectively (compared to multiple safety tools) from the point of view of users and developers of the safety tools that perform MCS analysis I with respect to their degree in supporting MCS analysis II and from the point of non-domain people using empirical strategies. The Spiral tool supports analysts with different visions, i.e., full vision, color deficiency protanopia, deuteranopia, and tritanopia. It supports 100 out of 103 (97%) requirements obtained from the triangulation and it fills 37 out of 39 (95%) gaps. Its usability was rated high (better than their best currently used tools) by the users of the safety and reliability tools (RiskSpectrum, ESSaRel, FaultTree+, and a self-developed tool) and at least similar to the best currently used tools from the point of view of the CAFTA tool developers. Its quality was higher regarding its degree of supporting MCS analysis II compared to the FaultTree+ tool. The time spent for discovering the critical MCSs from a problem size of 540 MCSs (with a worst case of all equal order) was less than a minute while achieving 99.5% accuracy. The scalability of the Spiral visualization was above 4000 MCSs for a comparison task. The Dynamic Slider reduces the interaction movements up to 85.71% of the previous sliders and solves the overlapping thumb issues by the sliders provides the 3D model view of the system being analyzed provides the ability to change the coloring of MCSs according to the color vision of the user provides selecting a BE (i.e., multi-selection of MCSs), thus, can observe the BEs' NoO and provides its quality provides two interaction speeds for panning and zooming in the MCS, BE, and model views provide a MCS, a BE, and a physical tab for supporting the analysis starting by the MCSs, the BEs, or the physical parts. It combines MCS analysis results and the model of an embedded system enabling the analysts to directly relate safety information with the corresponding parts of the system being analyzed and provides an interactive mapping between the textual information of the BEs and MCSs and the parts related to the BEs. Verifications and Assessments: I have evaluated all visualizations and the interaction widget both objectively and subjectively, and finally evaluated the final Spiral visualization tool also both objectively and subjectively regarding its perceived quality and regarding its degree of supporting MCS analysis II.

This research explores the development of web based reference software for characterisation of surface roughness for two-dimensional surface data. The reference software used for verification of surface characteristics makes the evaluation methods easier for clients. The algorithms used in this software are based on International ISO standards. Most software used in industrial measuring instruments may give variations in the parameters calculated due to numerical changes in calculation. Such variations can be verified using the proposed reference software. The evaluation of surface roughness is carried out in four major steps: data capture, data align, data filtering and parameter calculation. This work walks through each of these steps explaining how surface profiles are evaluated by pre-processing steps called fitting and filtering. The analysis process is then followed by parameter evaluation according to DIN EN ISO 4287 and DIN EN ISO 13565-2 standards to extract important information from the profile to characterise surface roughness.

LinTim is a scientific software toolbox that has been under development since 2007, giving the possibility to solve the various planning steps in public transportation. Although the name originally derives from "Lineplanning and Timetabling", the available functions have grown far beyond this scope. This document is the documentation for version 2020.02. For more information, see https://www.lintim.net

Es wurden Untersuchungen zur Expression und Wechsel von Serotypproteinen bei Paramecium primaurelia, Stamm 156 durchgeführt. Zum Nachweis der unterschiedlichen Serotypexpressionen wurden Immunofluoreszenzfärbungen und eine spezifische RT-PCR etabliert. Mit dieser Methode wurde der Ablauf eines temperaturinduzierten Serotypwechsels dokumentiert. Es wurde der Einfluss weiterer Umweltparameter auf die Ausprägung des Serotyps untersucht. Freilandexperimente sollten die Ausprägung der Serotypen unter multifaktorieller Reizeinwirkung zeigen. Zusätzlich konnte die Koexpression von zwei Serotypproteinen auf einer Zelle nachgewiesen werden.

Using molecular dynamics simulation, we study the cutting of an Fe single crystal using tools with various rake angles α. We focus on the (110)[001] cut system, since here, the crystal plasticity is governed by a simple mechanism for not too strongly negative rake angles. In this case, the evolution of the chip is driven by the generation of edge dislocations with the Burgers vector b = 1 2 [111], such that a fixed shear angle of φ = 54.7◦ is established. It is independent of the rake angle of the tool. The chip form is rectangular, and the chip thickness agrees with the theoretical result calculated for this shear angle from the law of mass conservation. We find that the force angle χ between the direction of the force and the cutting direction is independent of the rake angle; however, it does not obey the predictions of macroscopic cutting theories, nor the correlations observed in experiments of (polycrystalline) cutting of mild steel. Only for (strongly) negative rake angles, the mechanism of plasticity changes, leading to a complex chip shape or even suppressing the formation of a chip. In these cases, the force angle strongly increases while the friction angle tends to zero.

This thesis consists of five chapters: Chapter 1 contains the basics of the theory and is essential for the rest of the thesis. Chapters 2-5 are to a large extent independent of each other and can be read separately. - Chapter 1: Foundations of tropical intersection theory In this first chapter we set up the foundations of a tropical intersection theory covering many concepts and tools of its counterpart in algebraic geometry such as affine tropical cycles, Cartier divisors, morphisms of tropical cycles, pull-backs of Cartier divisors, push-forwards of cycles and an intersection product of Cartier divisors and cycles. Afterwards, we generalize these concepts to abstract tropical cycles and introduce a concept of rational equivalence. Finally, we set up an intersection product of cycles and prove that every cycle is rationally equivalent to some affine cycle in the special case that our ambient cycle is R^n. We use this result to show that rational and numerical equivalence agree in this case and prove a tropical Bézout's theorem. - Chapter 2: Tropical cycles with real slopes and numerical equivalence In this chapter we generalize our definitions of tropical cycles to polyhedral complexes with non-rational slopes. We use this new definition to show that if our ambient cycle is a fan then every subcycle is numerically equivalent to some affine cycle. Finally, we restrict ourselves to cycles in R^n that are "generic" in some sense and study the concept of numerical equivalence in more detail. - Chapter 3: Tropical intersection products on smooth varieties We define an intersection product of tropical cycles on tropical linear spaces L^n_k and on other, related fans. Then, we use this result to obtain an intersection product of cycles on any "smooth" tropical variety. Finally, we use the intersection product to introduce a concept of pull-backs of cycles along morphisms of smooth tropical varieties and prove that this pull-back has all expected properties. - Chapter 4: Weil and Cartier divisors under tropical modifications First, we introduce "modifications" and "contractions" and study their basic properties. After that, we prove that under some further assumptions a one-to-one correspondence of Weil and Cartier divisors is preserved by modifications. In particular we can prove that on any smooth tropical variety we have a one-to-one correspondence of Weil and Cartier divisors. - Chapter 5: Chern classes of tropical vector bundles We give definitions of tropical vector bundles and rational sections of tropical vector bundles. We use these rational sections to define the Chern classes of such a tropical vector bundle. Moreover, we prove that these Chern classes have all expected properties. Finally, we classify all tropical vector bundles on an elliptic curve up to isomorphisms.

The enzyme carbonic anhydrase isoform II (CAII), catalysing the hydration and dehydration of CO2, enhances transport activity of the monocarboxylate transporter isoform I (MCT1, SLC16A1) expressed in Xenopus oocytes by a mechanism that does not require CAII catalytic activity (Becker et al. (2005) J. Biol. Chem., 280). In the present study, we have investigated the mechanism of the CAII induced increase in transport activity by using electrophysiological techniques and a mathematical model of the MCT1 transport cycle. The model consists of six states arranged in cyclic fashion and features an ordered, mirror-symmetric, binding mechanism were binding and unbinding of the proton to the transport protein is considered to be the rate limiting step under physiological conditions. An explicit rate expression for the substrate °ux is derived using model reduction techniques. By treating the pools of intra- and extracellular MCT1 substrates as dynamic states, the time dependent kinetics are obtained by integration using the derived expression for the substrate °ux. The simulations were compared with experimental data obtained from MCT1-expressing oocytes injected with di®erent amounts of CAII. The model suggests that CAII increases the e®ective rate constants of the proton reactions, possibly by working as a proton antenna.

The various uses of fiber-reinforced composites, for example in the enclosures of planes, boats and cars, generates the demand for a detailed analysis of these materials. The final goal is to optimize fibrous materials by the means of “virtual material design”. New fibrous materials are virtually created as realizations of a stochastic model and evaluated with physical simulations. In that way, materials can be optimized for specific use cases, without constructing expensive prototypes or performing mechanical experiments. In order to design a practically fabricable material, the stochastic model is first adapted to an existing material and then slightly modified. The virtual reconstruction of the existing material requires a precise knowledge of the geometry of its microstructure. The first part of this thesis describes a fiber quantification method by the means of local measurements of the fiber radius and orientation. The combination of a sparse chord length transform and inertia moments leads to an efficient and precise new algorithm. It outperforms existing approaches with the possibility to treat different fiber radii within one sample, with high precision in continuous space and comparably fast computing time. This local quantification method can be directly applied on gray value images by adapting the directional distance transforms on gray values. In this work, several approaches of this kind are developed and evaluated. Further characterization of the fiber system requires a segmentation of each single fiber. Using basic morphological operators with specific structuring elements, it is possible to derive a probability for each pixel describing if the pixel belongs to a fiber core in a region without overlapping fibers. Tracking high probabilities leads to a partly reconstruction of the fiber cores in non crossing regions. These core parts are then reconnected over critical regions, if they fulfill certain conditions ensuring the affiliation to the same fiber. In the second part of this work, we develop a new stochastic model for dense systems of non overlapping fibers with a controllable level of bending. Existing approaches in the literature have at least one weakness in either achieving high volume fractions, producing non overlapping fibers, or controlling the bending or the orientation distribution. This gap can be bridged by our stochastic model, which operates in two steps. Firstly, a random walk with the multivariate von Mises-Fisher orientation distribution defines bent fibers. Secondly, a force-biased packing approach arranges them in a non overlapping configuration. Furthermore, we provide the estimation of all parameters needed for the fitting of this model to a real microstructure. Finally, we simulate the macroscopic behavior of different microstructures to derive their mechanical and thermal properties. This part is mostly supported by existing software and serves as a summary of physical simulation applied to random fiber systems. The application on a glass fiber reinforced polymer proves the quality of the reconstruction by our stochastic model, as the effective properties match for both the real microstructure and the realizations of the fitted model. This thesis includes all steps to successfully perform virtual material design on various data sets. With novel and efficient algorithms it contributes to the science of analysis and modeling of fiber reinforced materials.

Evaluation is an important issue for every scientific field and a necessity for an emerging soft-ware technology like case- based reasoning. This paper is a supplementation to the review of industrial case-based reasoning tools by K.-D. Althoff, E. Auriol, R. Barletta and M. Manago which describes the most detailed evaluation of commercial case-based reasoning tools currently available. The author focuses on some important aspects that correspond to the evaluation ofcase-based reasoning systems and gives links to ongoing research.

INRECA offers tools and methods for developing, validating, and maintaining decision support systems. INRECA's basic technologies are inductive and case-based reasoning, namely KATE -INDUCTION (cf., e.g., Manago, 1989; Manago, 1990) and S3-CASE, a software product based on PATDEX (cf., e.g., Wess,1991; Richter & Wess, 1991; Althoff & Wess, 1991). Induction extracts decision knowledge from case databases. It brings to light patterns among cases and helps monitoring trends over time. Case-based rea -soning relates the engineer's current problem to past experiences.

In this paper we will present a design model (in the sense of KADS) for the domain of technical diagnosis. Based on this we will describe the fully implemented expert system shell MOLTKE 3.0, which integrates common knowledge acquisition methods with techniques developed in the fields of Model-Based Diagnosis and Machine Learning, especially Case-Based Reasoning.

Within this paper we focus on both the solution of real, complex problems using expert system technology and the acquisition of the necessary knowledge from a case-based reasoning point of view. The development of systems which can be applied to real world problems has to meet certain requirements. E.g., all available information sources have to be identified and utilized. Normally, this involves different types of knowledge for which several knowledge representation schemes are needed, because no scheme is equally natural for all sources. Facing empirical knowledge it is important to complement the use of manually compiled, statistic and otherwise induced knowledge by the exploitation of the intuitive understandability of case-based mechanisms. Thus, an integration of case-based and alternative knowledge acquisition and problem solving mechanisms is necessary. For this, the basis is to define the "role" which case-based inference can "play" within a knowledge acquisition workbench. We will discuss a concrete casebased architecture, which has been applied to technical diagnosis problems, and its integration into a knowledge acquisition workbench which includes compiled knowledge and explicit deep models, additionally.

Fallbasiertes Schliessen ist ein derzeit viel diskutierter Problemlösesansatz. Dieser Beitrag gibt einen Überblick über den aktuellen Stand der Forschung auf diesem Gebiet, insbesondere im Hinblick auf die Entwicklung von Expertensystemen (einen ersten Schritt in diese Richtung stellte bereits der Beitrag von Bartsch-Spörl, [BS87] dar). Dazu stellen wir die dem fallbasierten Schliessen zugrundeliegenden Mechanismen vor. Ergänzt wird dies durch den Vergleich mit alternativen Verfahren wie z.B. regelbasiertes, analoges und induktives Schliessen sowie eine ausführliche Literaturübersicht.

We propose an integrated approach to decision support and diagnostic problems based on top-down induction of decision trees (TDIDT) and case-based reasoning (CBR).

In DS-CDMA, spreading sequences are allocated to users to separate different links namely, the base-station to user in the downlink or the user to base station in the uplink. These sequences are designed for optimum periodic correlation properties. Sequences with good periodic auto-correlation properties help in frame synchronisation at the receiver while sequences with good periodic cross- correlation property reduce cross-talk among users and hence reduce the interference among them. In addition, they are designed to have reduced implementation complexity so that they are easy to generate. In current systems, spreading sequences are allocated to users irrespective of their channel condition. In this thesis, the method of allocating spreading sequences based on users’ channel condition is investigated in order to improve the performance of the downlink. Different methods of dynamically allocating the sequences are investigated including; optimum allocation through a simulation model, fast sub-optimum allocation through a mathematical model, and a proof-of-concept model using real-world channel measurements. Each model is evaluated to validate, improvements in the gain achieved per link, computational complexity of the allocation scheme, and its impact on the capacity of the network. In cryptography, secret keys are used to ensure confidentiality of communication between the legitimate nodes of a network. In a wireless ad-hoc network, the broadcast nature of the channel necessitates robust key management systems for secure functioning of the network. Physical layer security is a novel method of profitably utilising the random and reciprocal variations of the wireless channel to extract secret key. By measuring the characteristics of the wireless channel within its coherence time, reciprocal variations of the channel can be observed between a pair of nodes. Using these reciprocal characteristics of common shared secret key is extracted between a pair of the nodes. The process of key extraction consists of four steps namely; channel measurement, quantisation, information reconciliation, and privacy amplification. The reciprocal channel variations are measured and quantised to obtain a preliminary key of vector bits (0; 1). Due to errors in measurement, quantisation, and additive Gaussian noise, disagreement in the bits of preliminary keys exists. These errors are corrected by using, error detection and correction methods to obtain a synchronised key at both the nodes. Further, by the method of secure hashing, the entropy of the key is enhanced in the privacy amplification stage. The efficiency of the key generation process depends on the method of channel measurement and quantisation. Instead of quantising the channel measurements directly, if their reciprocity is enhanced and then quantised appropriately, the key generation process can be made efficient and fast. In this thesis, four methods of enhancing reciprocity are presented namely; l1-norm minimisation, Hierarchical clustering, Kalman filtering, and Polynomial regression. They are appropriately quantised by binary and adaptive quantisation. Then, the entire process of key generation, from measuring the channel profile to obtaining a secure key is validated by using real-world channel measurements. The performance evaluation is done by comparing their performance in terms of bit disagreement rate, key generation rate, test of randomness, robustness test, and eavesdropper test. An architecture, KeyBunch, for effectively deploying the physical layer security in mobile and vehicular ad-hoc networks is also proposed. Finally, as an use-case, KeyBunch is deployed in a secure vehicular communication architecture, to highlight the advantages offered by physical layer security.

Business-relevant domain knowledge can be found in plain text across message exchanges among customer support tickets, employee message exchanges and other business transactions. Decoding text-based domain knowledge can be a very demanding task since traditional methods focus on a comprehensive representation of the business and its relevant paths. Such a process can be highly complex, time-costly and of high maintenance effort, especially in environments that change dynamically. In this thesis, a novel approach is presented for developing hybrid case-based reasoning (CBR) systems that bring together the benefits of deep learning approaches with CBR advantages. Deep Knowledge Acquisition Framework (DeepKAF) is a domain-independent framework that features the usage of deep neural networks and big data technologies to decode the domain knowledge with the minimum involvement from the domain experts. While this thesis is focusing more on the textual data because of the availability of the datasets, the target CBR systems based on DeepKAF are able to deal with heterogeneous data where a case can be represented by different attribute types and automatically extract the necessary domain knowledge while keeping the ability to provide an adequate level of explainability. The main focus within this thesis are automatic knowledge acquisition, building similarity measures and cases retrieval. Throughout the progress of this research, several sets of experiments have been conducted and validated by domain experts. Past textual data produced over around 15 years have been used for the needs of the conducted experiments. The text produced is a mixture between English and German texts that were used to describe specific domain problems with a lot of abbreviations. Based on these, the necessary knowledge repositories were built and used afterwards in order to evaluate the suggested approach towards effective monitoring and diagnosis of business workflows. Another public dataset has been used, the CaseLaw dataset, to validate DeepKAF when dealing with longer text and cases with more attributes. The CaseLaw dataset represents around 22 million cases from different US states. Further work motivated by this thesis could investigate how different deep learning models can be used within the CBR paradigm to solve some of the chronic CBR challenges and be of benefit to large-scale multi-dimensional enterprises.

In this paper we construct spline functions based on a reproducing kernel Hilbert space to interpolate/approximate the velocity field of earthquake waves inside the Earth based on traveltime data for an inhomogeneous grid of sources (hypocenters) and receivers (seismic stations). Theoretical aspects including error estimates and convergence results as well as numerical results are demonstrated.

In this paper we study the space-time asymptotic behavior of the solutions and derivatives to th incompressible Navier-Stokes equations. Using moment estimates we obtain that strong solutions to the Navier-Stokes equations which decay in \(L^2\) at the rate of \(||u(t)||_2 \leq C(t+1)^{-\mu}\) will have the following pointwise space-time decay \[|D^{\alpha}u(x,t)| \leq C_{k,m} \frac{1}{(t+1)^{ \rho_o}(1+|x|^2)^{k/2}} \] where \( \rho_o = (1-2k/n)( m/2 + \mu) + 3/4(1-2k/n)\), and \(|a |= m\). The dimension n is \(2 \leq n \leq 5\) and \(0\leq k\leq n\) and \(\mu \geq n/4\)

Der vorliegende Arbeits- und Forschungsbericht bietet eine Handreichung für Studiengangsentwickler_innen, um sie bei der Erstellung von Kompetenzprofilen zu unterstützen. Zu diesem Zweck werden drei verschiedene Tools der Kompetenzprofilerstellung vorgestellt. Diese umfassen die Stellenanzeigenanalyse, den Curriculumabgleich und Lehrendeninterviews. Diese Tools haben sich als sehr nützlich für die Entwicklung von kompetenzorientierten Studiengängen erwiesen. Die drei Verfahren werden einander gegenübergestellt und Implikationen für die Praxis abgeleitet. Dieser Bericht soll dazu beitragen, bedarfsorientierte Weiterbildungsangebote für die Region zu gestalten.

This study presents an energy-efficient ultra-low voltage standard-cell based memory in 28nm FD-SOI. The storage element (standard-cell latch) is replaced with a full- custom designed latch with 50 % less area. Error-free operation is demonstrated down to 450mV @ 9MHz. By utilizing body bias (BB) @ VDD = 0.5 V performance spans from 20 MHz @ BB=0V to 110MHz @ BB=1V.

A prime motivation for using XML to directly represent pieces of information is the ability of supporting ad-hoc or 'schema-later' settings. In such scenarios, modeling data under loose data constraints is essential. Of course, the flexibility of XML comes at a price: the absence of a rigid, regular, and homogeneous structure makes many aspects of data management more challenging. Such malleable data formats can also lead to severe information quality problems, because the risk of storing inconsistent and incorrect data is greatly increased. A prominent example of such problems is the appearance of the so-called fuzzy duplicates, i.e., multiple and non-identical representations of a real-world entity. Similarity joins correlating XML document fragments that are similar can be used as core operators to support the identification of fuzzy duplicates. However, similarity assessment is especially difficult on XML datasets because structure, besides textual information, may exhibit variations in document fragments representing the same real-world entity. Moreover, similarity computation is substantially more expensive for tree-structured objects and, thus, is a serious performance concern. This thesis describes the design and implementation of an effective, flexible, and high-performance XML-based similarity join framework. As main contributions, we present novel structure-conscious similarity functions for XML trees - either considering XML structure in isolation or combined with textual information -, mechanisms to support the selection of relevant information from XML trees and organization of this information into a suitable format for similarity calculation, and efficient algorithms for large-scale identification of similar, set-represented objects. Finally, we validate the applicability of our techniques by integrating our framework into a native XML database management system; in this context we address several issues around the integration of similarity operations into traditional database architectures.

Buses not arriving on time and then arriving all at once - this phenomenon is known from busy bus routes and is called bus bunching. This thesis combines the well studied but so far separate areas of bus-bunching prediction and dynamic holding strategies, which allow to modulate buses’ dwell times at stops to eliminate bus bunching. We look at real data of the Dublin Bus route 46A and present a headway-based predictive-control framework considering all components like data acquisition, prediction and control strategies. We formulate time headways as time series and compare several prediction methods for those. Furthermore we present an analytical model of an artificial bus route and discuss stability properties and dynamic holding strategies using both data available at the time and predicted headway data. In a numerical simulation we illustrate the advantages of the presented predictive-control framework compared to the classical approaches which only use directly available data.

Im vorliegenden Bericht werden die Erfahrungen und Ergebnisse aus dem Projekt OptCast zusammengestellt. Das Ziel dieses Projekts bestand (a) in der Anpassung der Methodik der automatischen Strukturoptimierung für Gussteile und (b) in der Entwicklung und Bereitstellung von gießereispezifischen Optimierungstools für Gießereien und Ingenieurbüros. Gießtechnische Restriktionen lassen sich nicht vollständig auf geometrische Restriktionen reduzieren, da die lokalen Eigenschaften nicht nur von der geometrischen Form des Gussteils, sondern auch vom verwendeten Material abhängen. Sie sind jedoch über eine Gießsimulation (Erstarrungssimulation und Eigenspannungsanalyse) adäquat erfassbar. Wegen dieser Erkenntnis wurde ein neuartiges Topologieoptimierungsverfahren unter Verwendung der Level-Set-Technik entwickelt, bei dem keine variable Dichte des Materials eingeführt wird. In jeder Iteration wird ein scharfer Rand des Bauteils berechnet. Somit ist die Gießsimulation in den iterativen Optimierungsprozess integrierbar.

Beim Bauen im Bestand werden häufig neue Stahlbetonbauteile kraftschlüssig an bestehende Tragstrukturen angeschlossen. Dies wird bei Ortbetonbauteilen günstig mit dem Übergreifungsstoß realisiert. Bis Ende der 1950-er Jahre wurden im Stahlbetonbau überwiegend glatte Betonstähle verwendet, bevor sie mit einer Übergangszeit bis Ende der 1970-er Jahre von den heute eingesetzten gerippten Betonstählen abgelöst wurden. Im Gegensatz zu den seit 1925 genormten Übergreifungsstößen mit Betonstählen gleicher Art und Güte sind kombinierte Übergreifungsstöße von Glatt- und Rippenstählen jedoch bis heute nicht geregelt. Zur Beseitigung dieses Defizits wurden im Rahmen dieser Arbeit differenzierte Bewehrungsregeln hergeleitet, die wissenschaftlich abgesicherte und gleichzeitig wirtschaftliche Lösungen für kombinierte Übergreifungsstöße ermöglichen, denn unter Einbeziehung des Rückbaus bestehender Altbetonsubstanz verlangt eine ökonomische Bauweise für Übergreifungsstöße von freigelegten historischen Glattstählen mit aktuell verwendeten Rippenstählen nach Vollstößen mit kleinstmöglichen Übergreifungslängen. Dabei sind die Anforderungen nach heute gültigem Regelwerk an die Zuverlässigkeit gegen Versagen im Grenzzustand der Tragfähigkeit (GZT) und die Sicherstellung der vorgegebenen Nutzung durch Begrenzung der Rissbreiten im Grenzzustand der Gebrauchstauglichkeit (GZG) zu beachten. Für verschiedene kombinierte Übergreifungsstöße von mit Endhaken versehenen glatten Betonstählen BStI und gerippten Betonstählen B500 mit geraden Stabenden oder Endhaken wurden die erforderlichen Übergreifungslängen anhand systematisch aufgebauter Versuchsreihen empirisch ermittelt. Dabei wurde ein grundlegendes Verständnis für die Tragwirkung kombinierter Übergreifungsstöße gewonnen und ein allgemeingültiges Lastübertragungsmodell erarbeitet. Zur Bemessung kombinierter Übergreifungsstöße wurde weiter ein Ingenieurmodell abgeleitet, welches die Tragwirkung derartiger Stöße zuverlässig beschreibt und die experimentell ermittelten Übergreifungslängen bestätigt. Dabei wurde unter Berücksichtigung der für den Verbund maßgebenden Betonzugfestigkeit, der Stahlspannungen und den Stabdurchmessern auf Basis statistischer Methoden ein Bemessungsdiagramm für die erforderliche Übergreifungslänge bestimmter Stoßkombinationen erarbeitet und eine ergänzende FE-Modellierung durchgeführt. Darauf aufbauend werden allgemeingültige Gleichungen zur Ermittlung der Bemessungswerte der Übergreifungslängen kombinierter Übergreifungsstöße mit Glattstahl BStI und Rippenstahl B500 angegeben und Konstruktionsregeln für in der Praxis regelmäßig vorkommende Kombinationen von Stabdurchmessern, Betongüten und Verbundbedingungen erarbeitet, die für Kombi-Stöße gleichwertig zu den Regeln des EC2 für den Neubaufall angewendet werden können.

The paper presents some adaptive load balance techniques for the simulation of rarefied gas flows on parallel computers. It is shown that a static load balance is insufficient to obtain a scalable parallel efficiency. Hence, two adaptive techniques are investigated which are based on simple algorithms. Numerical results show that using heuristic techniques one can achieve a sufficiently high efficiency over a wide range of different hardware platforms.

Durch den kontinuierlichen Anstieg von aussortierten, nicht mehr verwendbaren Fast Fashion Produkten wird die Textilbranche zu einem allgegenwärtigen Problem in der heutigen Gesellschaft. Ein Bericht der Ellen MacArthur Foundation zeigte auf, dass bisher weniger als 1% des für die Herstellung von Kleidung verwendeten Materials recycelt wird. Um die Wiederverwendung und -verwertung von Kleidung zu ermöglichen, müssen weitreichende Veränderungen innerhalb der Textilindustrie stattfinden, aber sich auch das Verhalten von Konsumenten verändern. Diese Arbeit soll deshalb die zentrale Fragestellung untersuchen, welche Maßnahmen unter Berücksichtigung des aktuellen Konsumentenverhaltens notwendig sind, um die Post-Verwendung von Kleidung nachhaltiger zu gestalten. In der vorliegenden Arbeit werden neue Erkenntnisse durch einen Mixed-Methods-Ansatz gewonnen. Um das Konsumentenverhalten hinsichtlich des Kleidungskonsums sowie der Verwendung und Verwertung von Gebrauchtkleidung beleuchten zu können, wird eine quantitative Online-Umfrage erstellt und durchgeführt. Im Zuge der Interpretation der quantitativen Forschung unterstützen zwei qualitative Experteninterviews den Erkenntnisgewinn. Darüber hinaus geben diese inhaltliche Unterstützung, um weitere Lösungsansätze für ein erfolgreiches Textilrecycling zu entwickeln. Der theoretische Rahmen der Arbeit wird durch eine Literaturrecherche unterstützt.

In this thesis, we present the basic concepts of isogeometric analysis (IGA) and we consider Poisson's equation as model problem. Since in IGA the physical domain is parametrized via a geometry function that goes from a parameter domain, e.g. the unit square or unit cube, to the physical one, we present a class of parametrizations that can be viewed as a generalization of polar coordinates, known as the scaled boundary parametrizations (SB-parametrizations). These are easy to construct and are particularly attractive when only the boundary of a domain is available. We then present an IGA approach based on these parametrizations, that we call scaled boundary isogeometric analysis (SB-IGA). The SB-IGA derives the weak form of partial differential equations in a different way from the standard IGA. For the discretization projection on a finite-dimensional space, we choose in both cases Galerkin's method. Thanks to this technique, we state an equivalence theorem for linear elliptic boundary value problems between the standard IGA, when it makes use of an SB-parametrization, and the SB-IGA. We solve Poisson's equation with Dirichlet boundary conditions on different geometries and with different SB-parametrizations.

As it is well known in statistical physics the stationary distribution can be obtained by maximizing entropy. We show how one can reconstruct the formula for entropy knowing the formula for the stationary distribution. A general case is discussed and some concrete physical examples are considered.

Die Zielsetzung dieser Arbeit bestand in der Entwicklung effizienter und nachhaltiger Verfahren zur Addition von N-H Nukleophilen an terminale Alkine und für die Insertion von CO2 in die C-H Bindung terminaler Alkine. Im ersten Teil dieser Dissertation wurde der Mechanismus der Ruthenium-katalysierten Addition von Amiden an terminale Alkine eingehend durch eine Kombination von Kontrollexperimenten, kinetischen Studien, spektroskopischen Untersuchungen und theoretischen Berechnungen untersucht. Zunächst wurden vier literaturbekannte Katalysezyklen identifiziert, die plausible Mechanismen für die Hydroamidierung terminaler Alkine darstellen. Aufbauend auf nachgewiesenen Elementarschritten chemisch verwandter Reaktionen wurde zusätzlich ein weiterer Mechanismus für die Hydroamidierung abgeleitet. Anschließend wurde eine Reihe von Kontrollexperimenten durchgeführt, mit deren Hilfe einzelne Elementarschritte der Katalysezyklen falsifiziert und somit Mechanismen ausgeschlossen werden konnten. Um herauszufinden, ob die Hydroamidierung mit dem einzig verbliebenen Mechanismus zutreffend beschrieben werden kann, wurden spektroskopische Studien durchgeführt. Diese Untersuchungen wurden vor, während und nach Hydroamidierungstestreaktionen durchgeführt, und auf diese Weise konnten zahlreiche postulierte Intermediate nachgewiesen und der verbleibende Katalysezyklus bekräftigt werden. Die in diesen mechanistischen Studien gewonnenen Erkenntnisse wurden zur Entwicklung einer neuen Katalysatorgeneration mit ausgesprochen hoher Selektivität für die Bildung wertvoller Z-Enamide und Z-Enimide genutzt. Das synthetische Potential wurde zudem durch die Darstellung der biologisch aktiven Naturstoffe Lansiumamid A und B, Lansamid I sowie Botryllamid C und E demonstriert. Im zweiten Teil dieser Arbeit gelang es, hocheffiziente Silber(I)/DMSO-katalysierte Methoden zur Carboxylierung terminaler Alkine mit CO2 bei Normaldruck zu entwickeln.

The rotational spinning of viscous jets is of interest in many industrial applications, including pellet manufacturing [4, 14, 19, 20] and drawing, tapering and spinning of glass and polymer fibers [8, 12, 13], see also [15, 21] and references within. In [12] an asymptotic model for the dynamics of curved viscous inertial fiber jets emerging from a rotating orifice under surface tension and gravity was deduced from the three-dimensional free boundary value problem given by the incompressible Navier-Stokes equations for a Newtonian fluid. In the terminology of [1], it is a string model consisting of balance equations for mass and linear momentum. Accounting for inner viscous transport, surface tension and placing no restrictions on either the motion or the shape of the jet’s center-line, it generalizes the previously developed string models for straight [3, 5, 6] and curved center-lines [4, 13, 19]. Moreover, the numerical results investigating the effects of viscosity, surface tension, gravity and rotation on the jet behavior coincide well with the experiments of Wong et.al. [20].

This work deals with the modeling and simulation of slender viscous jets exposed to gravity and rotation, as they occur in rotational spinning processes. In terms of slender-body theory we show the asymptotic reduction of a viscous Cosserat rod to a string system for vanishing slenderness parameter. We propose two string models, i.e. inertial and viscous-inertial string models, that differ in the closure conditions and hence yield a boundary value problem and an interface problem, respectively. We investigate the existence regimes of the string models in the four-parametric space of Froude, Rossby, Reynolds numbers and jet length. The convergence regimes where the respective string solution is the asymptotic limit to the rod turn out to be disjoint and to cover nearly the whole parameter space. We explore the transition hyperplane and derive analytically low and high Reynolds number limits. Numerical studies of the stationary jet behavior for different parameter ranges complete the work.