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The objective of this dissertation is to propose circuit architectures and techniques for built-in test and calibration of phase-locked loops. The design of phase-locked loops is first investigated to achieve a robust performance over process, temperature, voltage corners with minimum overhead. Different design techniques including adding loop programmability, increasing area efficiency, reducing noise immunity, and increasing frequency coverage are discussed. Secondly, built-in testing of phase-lock loops using sensors are proposed for loop dynamic parameters and reference spur. An integrator is designed to extract the subtle response from the system so that target parameters can be predicted. Different testing methodologies are applied different specification testing as well. Finally, an on chip phase-locked loop design is implemented for reference spur calibration. The phase-locked loop is designed with a programmable reference spur range. A static phase offset detector is included to identify the optimal setting of reference spur in the feedback system. The integrated jitter performance is improved by the calibration mechanism. The results of this thesis serve as an on-chip built-in self-test and self-calibration solution for embedded phase-locked loops in a high integration system.

Wir beginnen mit der Herleitung der asymptotischen Entwicklung der Spur des Wärmeleitungskernes, $\tr e^{-t\Delta}$, für $t\to0+$, wobei $\Delta$ der Laplace-Beltrami-Operator auf einer Mannigfaltigkeit mit Kegel-Singularitäten ist; dabei folgen wir der Arbeit von Brüning und Seeley. Dann untersuchen wir, wie die Koeffizienten der Entwicklung mit der Geometrie der Mannigfaltigkeit zusammenhängen, insbesondere fragen wir, ob die (mögliche) Singularität der Mannigfaltigkeit aus den Koeffizienten - und damit aus dem Spektrum des Laplace-Beltrami-Operators - abgelesen werden kann. In wurde gezeigt, dass im zweidimensionalen Fall ein logarithmischer Term und ein nicht lokaler Term im konstanten Glied genau dann verschwinden, wenn die Kegelbasis ein Kreis der Länge $2\pi$ ist, die Mannigfaltigkeit also geschlossen ist. Dann untersuchen wir wir höhere Dimensionen. Im vier-dimensionalen Fall zeigen wir, dass der logarithmische Term genau dann verschwindet, wenn die Kegelbasis eine sphärische Raumform ist. Wir vermuten, dass das Verschwinden eines nicht lokalen Beitrags zum konstanten Term äquivalent ist dazu, dass die Kegelbasis die runde Sphäre ist; das kann aber bisher nur im zyklischen Fall gezeigt werden. Für geraddimensionale Mannigfaltigkeiten höherer Dimension und mit Kegelbasis von konstanter Krümmung zeigen wir weiter, dass der logarithmische Term ein Polynom in der Krümmung ist, das Wurzeln ungleich 1 haben kann, so dass erst das Verschwinden von mehreren Termen - die derzeit noch nicht explizit behandelt werden können - die Geschlossenheit der Mannigfaltigkeit zur Folge haben könnte. / We derive a detailed asymptotic expansion of the heat trace for the Laplace-Beltrami operator on functions on manifolds with one conic singularity, using the Singular Asymptotics Lemma of Jochen Bruening and Robert T. Seeley. Then we investigate how the terms in the expansion reflect the geometry of the manifold. Since the general expansion contains a logarithmic term, its vanishing is a necessary condition for smoothness of the manifold. It is shown in the paper by Bruening and Seeley that in the two-dimensional case this implies that the constant term of the expansion contains a non-local term that determines the length of the (circular) cross section and vanishes precisely if this length equals $2\pi$, that is, in the smooth case. We proceed to the study of higher dimensions. In the four-dimensional case, the logarithmic term in the expansion vanishes precisely when the cross section is a spherical space form, and we expect that the vanishing of a further singular term will imply again smoothness, but this is not yet clear beyond the case of cyclic space forms. In higher dimensions the situation is naturally more difficult. We illustrate this in the case of cross sections with constant curvature. Then the logarithmic term becomes a polynomial in the curvature with roots that are different from 1, which necessitates more vanishing of other terms, not isolated so far.

Orientador: Aparecido Carlos Gonçalves / Banca: Gilberto Pechoto de Melo / Banca: Jorge Nei Brito / Resumo: Todo sistema ou equipamento mecânico está sujeito a processos de deterioração. Esta deterioração leva ao aparecimento de defeitos que podem atrapalhar a continuidade e qualidade do serviço (produção). Uma quebra não prevista traduz-se por uma parada brusca, levando geralmente a grandes prejuízos e a perda de tempo de produção. Para evitar paradas inesperadas eficientemente e reduzir os custo de manutenção são utilizadas técnicas de manutenção preditiva. Entre todas as técnicas existentes, as mais importantes na manutenção de redutores são a análise de vibrações e a análise de partículas de desgaste. A determinação da severidade, modos e tipos de desgaste em máquinas pode ser feita pela identificação da morfologia, acabamento superficial, coloração, natureza, quantidade e tamanho das partículas encontradas em amostras de óleo ou graxas. Pela análise do sinal vibratório é possível tomar decisões de intervir ou não na operação da máquina, aumentando a disponibilidade e confiabilidade da mesma. A integração destas técnicas tem o potencial para revolucionar práticas industriais e proporcionar para as companhias um significante alívio econômico. Para estudo destas duas técnicas, neste trabalho foi construída uma bancada experimental com o propósito de se realizar a manutenção preditiva em um redutor de velocidades. O Sistema foi posto para funcionar até o limite de utilização. Foram utilizados lubrificantes recomendados pelo fabricante do redutor, lubrificantes com contaminação líquida em várias porcentagens e lubrificantes com contaminação sólida em duas porcentagens. Foram observadas que para baixas rotações a análise de partículas foi vantajosa em relação à análise de vibrações e que a contaminação por água, embora tenha ocasionado uma maior oxidação do sistema, proporcionou menor desgaste do que o lubrificante sem contaminação. / Abstract: Every system or mechanical equipment is subject to deterioration processes. This deterioration takes to the apparition of defects that can disturb the continuity and quality of the service (production). One break not foreseen translates for an abrupt stop, usually taking to great damages and waste of time of production. For avoid unexpected stops efficiently and reduce the cost, predictive maintenance techniques are used. Among all the existent techniques, the most important in the maintenance of reducers are vibration analysis and wear particle analysis. The determination of the severity, wear modes and types in machines can be done through the identification of the morphology, surface finishing, coloration, nature, quantity and size of the particles found in oil samples or lubricating greases. Vibration Analysis is one of the oldest techniques in the maintenance. By vibration sign analysis it is possible to make decisions of intervening or not in the machine operation, improving its availability and reliability. The integration of these techniques has the potential to revolutionize industry practices and provide a significant industrial economic relief. For the study of these two techniques, in this work, an experimental bench was built with the purpose of doing the predictive maintenance in a reducer. The System was put to work until the limit. It was observed that for low rotations the wear particle analysis were advantageous in relation to the vibration analysis and for oil with water contamination, although causing a larger oxidation in the system, a smaller wear than the lubricant without contamination was provided. / Mestre

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The aim of this master's thesis is to build artificial neural network that is able to calculate varying single tooth-pair mesh stiffness of spur gear for given input parameters. The training set for this network was determined by computational modelling by finite element method. Therefore, creating of computational model and mesh stiffness calculating were a partial aim of this thesis. Input parameters for stiffness calculation were number of driving and driven gear teeth and gear loading. Creating of computational model and performing series of simulations was followed by creating artificial neural network. Multilayer neural network with backpropagation training was chosen as a type of the network. Created neural network is sufficiently efficient and can determine varying mesh stiffness in input set range for learned input parameters and for values of parameters that are not included in training set as well. This neural network can be used for varying single tooth-pair mesh stiffness estimation in input set range.

The diploma thesis deals with the perpendicular crossing of tram track with railway siding. The structure of crossing is described both in the Czech Republic and in the world. The aim of the thesis is to find the recommended design solution for the crossing of tram and railway tracks with regard to legislation and feasibility. After a comparison of the existing structures is chosen which satisfies the conditions of feasibility.

This diploma thesis is focused on the implementation of the educational role of the experimental station for measuring the effectiveness of gears. The proposed laboratory task "Experimental measurement of the effectiveness of gears" is intended to familiarize students with the basic principles of gears and especially highlight the issue of the effectiveness of gears. In this presented thesis, it is also suggested the possibility of expanding the educational use of the experimental station. This extension deals with vibration diagnostics of frequencies of gears.

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No description available.