Listing 1 - 10 of 140 | << page >> |
Sort by
|
Choose an application
By restricting to Gaussian distributions, the optimal Bayesian filtering problem can be transformed into an algebraically simple form, which allows for computationally efficient algorithms. Three problem settings are discussed in this thesis: (1) filtering with Gaussians only, (2) Gaussian mixture filtering for strong nonlinearities, (3) Gaussian process filtering for purely data-driven scenarios. For each setting, efficient algorithms are derived and applied to real-world problems.
Zustandsschätzung --- GaußprozesseBayesian statistics --- Kalman filter --- Gaussian processes --- Kalman-Filter --- state estimation --- filtering --- Bayes'sche Statistik
Choose an application
In dieser Arbeit wird ein Verfahren entwickelt, das die Online-Schätzung fraktionaler Impedanzmodelle im Zeitbereich ermöglicht. Hierzu wird ein neuartiges Verfahren vorgestellt, welches die Beschreibung der Impedanz durch ein Zustandsraummodell im Zeitbereich ermöglicht. Zur Schätzung der Modellparameter werden Sigma-Punkt-Kalman-Filter eingesetzt. Die Einsetzbarkeit des Verfahrens wird durch Simulationsbeispiele belegt.
Choose an application
State estimation techniques for centralized, distributed, and decentralized systems are studied. An easy-to-implement state estimation concept is introduced that generalizes and combines basic principles of Kalman filter theory and ellipsoidal calculus. By means of this method, stochastic and set-membership uncertainties can be taken into consideration simultaneously. Different solutions for implementing these estimation algorithms in distributed networked systems are presented.
distributed estimation --- Kalman filter --- set-membership estimation --- Bayesian state estimation
Choose an application
A ubiquitous challenge in many technical applications is to estimate an unknown state by means of data that stems from several, often heterogeneous sensor sources. In this book, information is interpreted stochastically, and techniques for the distributed processing of data are derived that minimize the error of estimates about the unknown state. Methods for the reconstruction of dependencies are proposed and novel approaches for the distributed processing of noisy data are developed.
Schätztheorie --- Kalman Filter --- estimation theory --- Sensornetze --- Verteilte SystemsData fusion --- distributed systems --- Datenfusion --- sensor networks --- Kalman filtering
Choose an application
A nonparametric identification method for highly nonlinear systems is presented that is able to reconstruct the underlying nonlinearities without a priori knowledge of the describing nonlinear functions. The approach is based on nonlinear Kalman Filter algorithms using the well-known state augmentation technique that turns the filter into a dual state and parameter estimator, of which an extension towards nonparametric identification is proposed in the present work.
Choose an application
In dieser Arbeit werden zur Überwachung von Drei-Wege-Katalysatoren zwei neue modellbasierte On-Board-Diagnoseverfahren vorgestellt. Zunächst wurde ein die Alterung mit berücksichtigendes physikalisches Katalysatormodell entwickelt. Dieses bildet die Grundlage der neuen Diagnoseverfahren, bei denen ein den aktuellen Zustand des Katalysators schätzender Sigma-Punkt-Kalman-Filter zum Einsatz kommt. Das große Potential dieser neuen Diagnoseverfahren zeigen die abschließend präsentierten Ergebnisse.
Abgastemperatur --- Spektrale Verfahren --- Constrained Sigma-Punkt-Kalman-Filter --- Drei-Wege-Katalysator-Modell --- On-Board-Diagnose
Choose an application
In dieser Arbeit wird eine gleisselektive, bordautonome Ortungsplattform für Schienenfahrzeuge unter Verwendung diversitärer, redundanter Sensoren vorgestellt. Durch die Verwendung eines neuartigen Wirbelstrom-Sensorsystems in Kombination mit inertialer Sensorik, GPS und einer digitalen Streckenkarte werden die Anforderungen an eine sicherheitsrelevante Ortungsplattform erfüllt. Hierbei werden unterschiedliche Fusionsansätze hergeleitet und anhand realer Messdaten bewertend verglichen.
Map-Matching --- Schienenfahrzeuge --- Ortung --- Weichenerkennung --- Kalman-Filter --- Wirbelstrom-Sensorsystem --- Integriertes Navigationssystem --- Informationsfusion
Choose an application
Nowadays, football is by far the most popular sport in the world. Its huge audience obviously attracts many fields, including the field of game analysis. In recent years, deep learning has brought progress to automated match analysis but a challenge remains strenuous: the ball tracking on football sequences. Indeed, the ball is often represented by few pixels on the football videos and many other object have a similar appearance. In addition, the ball can be occluded by a player or in front of a line with similar color. All these circumstances make the ball tracking a challenging objective. In this work, an offline ball tracking system based on deep learning for soccer sequences is implemented. The system is divided into two main parts: a ball detector followed by a ball tracking method. The detector is based on a deep convolutional neural network for image segmentation. A dataset composed of semi-synthetic images representing a synthetic ball in front of a real frame from a football video sequence is created to train the network. The objective of the detector is to identify ball candidates on each frame of the sequence. Then the tracking method treats all the candidates of the sequence to generate candidate trajectories with the exploitation of the Kalman filter. A score is assigned to each trajectory thanks to the use of a deep neural network for image classification. The trajectories with the highest score are selected as ball trajectories. Finally, a cubic spline interpolation estimates the ball positions between the trajectories. Evaluated on sequences of professional competitions, this ball tracking system allows an identification of the ball position on more than 80% of the images of most of the evaluated sequences, without having any false detection. Moreover, the evaluation highlights the ability of the system to estimate the ball positions during occlusion on a few frames.
Deep Learning --- Ball Tracking --- Neural Network --- Ball Detector --- Kalman Filter --- Ingénierie, informatique & technologie > Sciences informatiques
Choose an application
The drone industry is currently experiencing a fast-paced development which leads to the creation of multitude of various products. An emerging trend is the search of increased smartness and autonomy of the machines. A prerequisite for this quest of autonomy is however the need of having a robust and reliable state estimate over time. In this Master Thesis, we explore different possibilities of achieving this in real-time by using an on-board mounted camera in pair with other sensors for the Fleye, a drone developed by Aerobot. More specifically, we focus our attention on the Multi-State Constraints Kalman Filter for which we provide a detailed explanation and an implementation designed for the Fleye. The strength of this filter resides in its relatively good computational efficiency compared to its alternatives and in its ability to deal with some hardware uncertainties such as an approximative knowledge of the relative position of the different sensors. A method developed to generate synthetic data allowing to test the performance of visual-inertial odometry algorithms is presented in this work. Performance tests made on synthetic and experimental data show that the implemented filter is consistent but still requires further improvements in order to compete with current state-of-the-art solutions.
Choose an application
This thesis aims at finding whether equity mutual fund managers react to changes in the macroeconomy by reallocating their funds in diverse industries. To do so, we conducted an asset allocation model, through a Kalman filter, using Fama and French industry portfolios. Among other findings, we found that equity mutual funds increase their allocation towards the consumer goods industry in times of economic uncertainty, managers do not exhibit significant selection skill and equity mutual funds adopt different behaviours depending on their defined strategy. Finally, we could not provide evidence that equity mutual fund managers were able to time the market.
Listing 1 - 10 of 140 | << page >> |
Sort by
|