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Institute
Stability of control systems is one of the central subjects in control theory. The classical asymptotic stability theorem states that the norm of the residual between the state trajectory and the equilibrium is zero in limit. Unfortunately, it does not in general allow computing a concrete rate of convergence particularly due to algorithmic uncertainty which is related to numerical imperfections of floating-point arithmetic. This work proposes to revisit the asymptotic stability theory with the aim of computation of convergence rates using constructive analysis which is a mathematical tool that realizes equivalence between certain theorems and computation algorithms. Consequently, it also offers a framework which allows controlling numerical imperfections in a coherent and formal way. The overall goal of the current study also matches with the trend of introducing formal verification tools into the control theory. Besides existing approaches, constructive analysis, suggested within this work, can also be considered for formal verification of control systems. A computational example is provided that demonstrates extraction of a convergence certificate for example dynamical systems.
The intention of this thesis is to examine the beneficial impact of renewable energies in general and biogas technologies in particular on socioeconomic status of people, by considering all applicable sides affecting its development as per political, cultural, environmental, and institutional means. As energy and development are very much correlative with each other, biogas technologies figure prominently as part of a decentralized, sustainable, renewable, energy network especially in rural areas of Nepal.
Cancer is one of the main causes of death in developed countries, and cancer treatment heavily depends on successful early detection and diagnosis. Tumor biomarkers are helpful for early diagnose. The goal of this discovery method is to identify genetic variations as well as changes in gene expression or activity that can be linked to a typical cancer state.
First, several cancer gene signaling pathways were introduced and then combined. 27 candidate genes were selected, through the analysis of several data sets in the GEO database, a few expression difference matrices were established. Those candidate genes were tested in the matrices and found five genes PLA1A, MMP14, CCND1, BIRC5 and MYC that have the potential to be tumor biomarkers. Two of these genes have been further discussed, PLA1A is a potential biomarker for prostate cancer, and MMP14 can be considered as a biomarker for NSC lung cancer.
Finally, the significance of this study and the potential value of the two genes are discussed, and the future research in this direction is a prospect.
The loss of photoreceptors is a major course for visual impairment and blindness with no cure currently established. Photoreceptor replacement into mouse models of retinal degeneration is currently investigated as a potential future therapy. To evaluate visual function in mice before and after treatment two vision-based behavioral tests (optomotor tracking and the light/dark box) were investigated including their feasibility to distinguish between rod and cone photoreceptor function. Both methods turned out to be an objective and reliable readout for vision ability in wildtype mice and mice with vision impairment due to retinal degeneration. The capability of the methods to assess slight vision improvements have to be further evaluated.
Therefore options for improvement of the established tests and an idea for a new test paradigm have been introduced.
This thesis was written in order to prove the expediency of startup ecosystem support and to develop practical recommendations for Belarusian government based on the analysis of successful practices in the U.S. and Lithuania.
It covers the essence of a “startup company” and a “startup ecosystem” as well as provides the analysis of socioeconomic impact of startup companies with particular focus on job creation. It sheds light on the best startup support policies in the U.S., where most prominent startup ecosystems are operating, and Lithuania as a country with similar to Belarusian preconditions and a rapidly
developing ecosystem. Furthermore, this paper deals with Belarus‘s peculiarities regarding fostering startup ecosystem growth. It assesses recent economic development of Belarusian IT sector and gives an insight into its competitive advantages and challenges.
The subsequent paper is based on internet research using articles, presentations, reports and studies, websites and official legal documents.
Classification of time series has received an important amount of interest over the past years due to many real-life applications, such as environmental modeling, speech recognition, and computer vision.
In my thesis, I focus on classification of time series by LVQ classifiers. To learn a classifiers, we need a training set. In our case, every data point in the training set contains a sequence (an ordered set) of feature vectors. Thus, the first task is to construct a new feature vector (or matrix) for each sequence.
Inspired by [2], I use Hankel matrices to construct the new feature vectors. This choice comes from a basic assumption that each time series is generated by a single or a set of unknown Linear Time Invariant (LTI) systems.
After generating new feature vectors by Hankel matrices, I use two approaches to learn a classifier: Generalized Learning Vector Quntization (GLVQ) and Median variant of Generalized Learning Vector Quantization (mGLVQ).
Large bone defects are a major clinical problem affecting elderly disproportionally, particularly indeveloped countries where this population is the fastest growing. Current treatments include autologous and allogenous bone grafts, bone elongation with the Ilizarov technique, bone graft substitutes, and electrical stimulation. Each of these approaches enjoys varying degrees of success, however, each also has its associated problems and complications. A new, still experimental, treatment is Tissue Engineering that combines scaffolds, osteogenic stem cells and growth factors, and is showing encouraging early results in preclinical and initial clinical studies.
Electrical stimulation has been shown to enhance bone healing by promoting mesenchymal stem cell migration, proliferation, and differentiation. In the present study we combine Tissue Engineering with Electrical Stimulation and hypothesize that this combined approach will have a synergistic effect resulting in enhanced new bone formation. In our in vitro experiments we observed that the levels of electrical stimulation we tested had no cytotoxic effect, instead increased osteogenic differentiation, as determined by enhanced expression of the osteogenic marker, Alkaline Phosphatase. These findings support our hypothesis by demonstrating that in the tissue-engineering environment electrical stimulation promotes bone formation. The bioinformatics part of this project consisted of gene network analysis, identification of the top 10 osteogenic markers and analyzis of genegene interactions. We observed that in studies of stem cells from both human and rat the genes, BMPR1A, BMP5, TGFßR1, SMAD4, SMAD2, BMP4, BMP7, RUNX3, and CDKN1A, are associated with osteogenesis and interact with each other. We observed a total of 31 interactions for human and 29 interactions for rat stem cells. While this approach needs to be proven experimentally, we believed that these in vitro and in silico analyses could compliment each other and in doing so contribute to the field of bone healing research.
Die vorliegende Diplomarbeit befasst sich mit der Analyse, Auswertung und Empfehlung einer Berechnungsmethode für die axiale Klemmkraft und Wellenmuttern-Anzugsmoment bei Hochgenauigkeits-Axial-Schrägkugellagern für Gewindetriebe. Des Weiteren wird der Einfluss der Klemmkraft bzw. WellenmutternAnzugsmomentes auf unterschiedliche Lagersätze und –anordnungen überprüft und Korrekturfaktoren dafür erarbeitet
The design of an interview model based on competencies arises from the need to have highly qualified people that contribute to the achievement of organizational objectives. It intendes to shape the department of human resources into a strategic area of the company. To achieve this, organizational competencies are defined, and guidelines for the elaboration of a portfolio of questions, as well as the design of a competency dictionary, are established. These serve as tools for the human resources processes of the company Visbal Moreno y Sucesores Ltd. Through this work, the importance of the human factor is exposed as part of the organizational strategy.