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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

Autonomous Motion Learning for Near Optimal Control

Jennings, Alan Lance 21 August 2012 (has links)
No description available.
452

Fibonacci Numbers and Associated Matrices

Meinke, Ashley Marie 18 July 2011 (has links)
No description available.
453

A Study of Bioluminescent and Magnetic Resonance Imaging in Murine Glioblastoma Models.

Boyer, Peter Gerard January 2014 (has links)
No description available.
454

Inference of string mappings for speech technology

Jansche, Martin 15 October 2003 (has links)
No description available.
455

The Infimum Problem as a Generalization of the Inclusion Problem for Automata

Borgwardt, Stefan 03 January 2024 (has links)
This thesis is concerned with automata over infinite trees. They are given a labeled infinite tree and accept or reject this tree based on its labels. A generalization of these automata with binary decisions are weighted automata. They do not just decide 'yes' or 'no', but rather compute an arbitrary value from a given algebraic structure, e.g., a semiring or a lattice. When passing from unweighted to weighted formalisms, many problems can be translated accordingly. The purpose of this work is to determine the feasibility of solving the inclusion problem for automata on infinite trees and its generalization to weighted automata, the infimum aggregation problem.
456

A BRAIN MODEL FOR THE STUDY OF MR SUSCEPTIBILITY INDUCED PHASE BEHAVIOR

Buch, Sagar 10 1900 (has links)
<p>MR phase images contain essential information about local magnetic susceptibility sources in the brain, creating a new type of contrast in magnetic resonance imaging (MRI). The goal of this thesis is to demonstrate with a model of the brain how accurately the transformation of phase to susceptibility takes place.</p> <p>A 3D brain model uses the Forward process to calculate magnetic field perturbations caused by susceptibility properties of the tissues in the model. Homodyne High Pass (HP) filter and SHARP algorithm are used to process the simulated phase images. Similarly, MR magnitude data are simulated using tissue properties such as T<sub>1</sub>, T<sub>2</sub><sup>*</sup> relaxation times and spin density.</p> <p>The halo ring around red nucleus in the real phase data is believed to be an indicator of a capsule around red nucleus. Similar effect is seen in the simulated phase images without including the capsule of red nucleus in the model, this comparison explains that the halo effect may just be entirely or a part of the phase behavior around red nucleus. A negative susceptibility in the internal capsule region, seen in both simulated and real susceptibility maps, is discussed as a possible artifact caused by the processing techniques after comparing the simulated susceptibility maps produced from unprocessed and processed phase data. The brain model is used to determine the optimum echo time of the initial gradient echo sequence in order to produce a high quality susceptibility map with reasonably low error and better time efficiency.</p> / Master of Applied Science (MASc)
457

Imagerie pondérée en diffusion dans la narcolepsie et l’hypersomnie idiopathique

Groulx, William 12 1900 (has links)
Introduction : Les analyses de connectivité cérébrale dans les trois troubles majeurs d'hypersomnolence centrale, la narcolepsie de type I (NT1), de type II (NT2) et de l’hypersomnie idiopathique (HI) sont rares dans la littérature. Les études de connectivité structurelle indiquent comment les réseaux de fibres de matière blanche sont organisés et affectés dans le cas de patients atteints de troubles du système nerveux central. L’objectif principal de cette étude est d’observer si la connectivité structurelle est affectée dans la NT1, NT2 et l’HI comparativement à des sujets sains. Une diminution dans les mesures de connectivité globale dans les troubles d’hypersomnolence centrale et leur association à la sévérité des symptômes comme la somnolence sont supposées. Méthodes : Des sujets sains (HC, n=8) et des patients diagnostiqués avec soit l’HI (n=14), la NT1 (n=15) ou la NT2 (n=14) ont suivi une séance d'IRM avec l’imagerie pondérée en diffusion. Les mesures d’intégration (efficacité globale) et de ségrégation (efficacité locale et transitivité), l’index de petit monde, et le degré nodal ont été utilisés. Les variables cliniques d’inertie de sommeil, la somnolence, la dépression, l’anxiété, la sévérité d’hypersomnolence et la durée symptomatique ont été évaluées. Résultats et conclusion : Seul le groupe HI a démontré une efficacité globale significativement plus élevée que le groupe HC, qui pourrait être expliquée par une augmentation de la transmission GABAergique. Le groupe NT2 a démontré une association entre l’efficacité globale et les scores au ESS et HSI. Aucune autre différence significative n’a été démontrée pour les autres mesures globales ni pour les mesures régionales entre les groupes. / Introduction: Structural connectivity studies comparing all three central primary hypersomnolence disorder types, i.e., narcolepsy type I (NT1), type II (NT2) and idiopathic hypersomnia (IH) have been scarce. Differences in structural connectivity may indicate how circuits in the brain are affected in hypersomnolence disorders compared to healthy controls. The main goal of this study is to assess if differences exist between NT1, NT2 and IH patients compared to controls using structural imaging analyses. A decrease in global connectivity measures in all three central hypersomnolence disorders compared to healthy controls and an association to symptom severity like sleepiness is hypothesized. Methods: Patients diagnosed with either NT1 (n=15), NT2 (n=13) or IH (n=14), as well as healthy participants (HC, n=8) were recruited and underwent a DWI session. Data were preprocessed and analyzed using a model based on constrained spherical deconvolution with multi-shell and multi-tissue parameters. Integration (global efficiency) and segregation measures, small-world index and nodal degree were used to evaluate structural connectivity. Clinical variables of sleep inertia, sleepiness, hypersomnia severity, depression, anxiety, and disease duration were evaluated. Results and conclusion: Only IH patients showed a significantly higher global efficiency than HC. An increase in GABAergic transmission is a potential mechanism, but how it relates to IH symptoms is unclear. Global efficiency was also demonstrated to be associated with ESS and HSI scores in the NT2 group. There were no differences between groups for any of the other global or local measures.
458

The data processing to detect correlated movement of Cerebral Palsy patient in early phase

Pyon, Okmin 03 February 2016 (has links)
The early diagnosis of CP (Cerebral Palsy) in infants is important for developing meaningful interventions. One of the major symptoms of the CP is lack of the coordinated movements of a baby. The bilateral coordinated movement (BCM) is that a baby shows in the early development stage. Each limb movement shows various ranges of speed and angle with fluency in a normal infant. When a baby has CP the movements are cramped and more synchronized. A quantitative method is needed to diagnose the BCM. Data is collected from 3-axis accelerometers, which are connected, to each limb of the baby. Signal processing the collected data using short time Fourier transforms, along with the formation of time-dependent transfer functions and the coherence property is the key to the diagnostic approach. Combinations of each limb's movement and their relationship can represent the correlated movement. Data collected from a normal baby is used to develop the technique for identifying the fidgety movement. Time histories and the resulting diagnostic tool are presented to show the regions of the described movement. The evaluation of the transduction approach and the analysis is discussed in detail. The application of the quantitative tool for the early diagnosis of CP offers clinicians the opportunity to provide interventions that may reduce the debilitating impact this condition has on children. Tools such as this can also be used to assess motor development in infants and lead to the identification and early intervention for other conditions. / Master of Science
459

Integrated Enhancement of Testability and Diagnosability for Digital Circuits

Rahagude, Nikhil Prakash 29 November 2010 (has links)
While conventional test point insertions commonly used in design for testability can improve fault coverage, the test points selected may not necessarily be the best candidates to aid <em>silicon diagnosis</em>. In this thesis, test point insertions are conducted with the aim to detect more faults and also synergistically distinguish currently indistinguishable fault-pairs. We achieve this by identifying those points in the circuit, which are not only hard-to-test but also lie on distinguishable frontiers, as Testability-Diagnosability (TD) points. To this end, we propose a novel low-cost metric to identify such TD points. Further, we propose a new DFT + DFD architecture, which adds just one pin (to identify test/functional mode) and small additional combinational logic to the circuit under test. Our experiments indicate that the proposed architecture can distinguish 4x more previously indistinguishable fault-pairs than existing DFT architectures while maintaining similar fault coverages. Further, the experiments illustrate that quality results can be achieved with an area overhead of around 5%. Additional experiments conducted on hard-to-test circuits show an increase in <em>fault coverage</em> by 48% while maintaining similar diagnostic resolution. Built-in Self Test (BIST) is a technique of adding additional blocks of hardware to the circuits to allow them to perform self-testing. This enables the circuits to test themselves thereby reducing the dependency on the expensive external automated test equipment (ATE). At the end of a test session, BIST generates a signature which is a compaction of the obtained output responses of the circuit for that session. Comparison of this signature with the reference signature categorizes the circuit as error free or buggy. While BIST provides a quick and low cost alternative to check circuit's correctness, diagnosis in BIST environment remains poor because of the limited information present in the lossily compacted final signature. The signature does not give any information about the possible defect location in the circuit. To facilitate diagnosis, researchers have proposed the use of two additional on-chip embedded memories,response memory to store reference responses and fail memory to store failing responses. We propose a novel architecture in which only one additional memory is required. Experimental results conducted on benchmark circuits substantiate that the same fault coverage can be maintained using just 5% of the available test vectors. This reduces the size of memory required to store responses which in turn reduces area overhead. Further, by adding test points to the circuit using our proposed architecture, we can improve the diagnostic resolution by 60% with respect to external testing. / Master of Science
460

Weighing in on the HOM-Problem: A Study of Weighted Tree Automata and Homomorphisms

Nász, Andreea-Teodora 05 August 2024 (has links)
Theoretical computer science is inconceivable without the concept of finite automata. These devices and their upgraded versions, weighted automata, are widely used to implement (quantitative) evaluations of inputs in image compression, probabilistic systems or natural language processing. In particular, the handling of natural language requires more sophisticated input structures such as trees. Together with the quantitative dimension, this leads to the model of weighted tree automata and the regular weighted tree languages they recognize. From a computational point of view, regular languages have many advantages: They allow compact representations, many of their fundamental properties are decidable and they are closed under several natural operations. One exception to this, however, are tree homomorphisms. It is long known that these deterministic transformations do not necessarily preserve regularity, but for decades, it was an open problem whether regularity of the homomorphic image is decidable. In 2010, this so-called HOM-problem was solved by Godoy, Giménez, Ramos and Àlvarez. More precisely, given a tree automaton and a tree homomorphism, it can be decided in exponential time whether the homomorphic image of the recognized language is again regular. In this thesis, we approach different weighted versions of this problem, where the input automaton is a weighted device over a certain semiring. We prove the decidability of this problem, both for restricted and unrestricted input, for different classes of weight domains. For this, we introduce a novel extension of weighted tree automata with explicit constraints, which we use to represent and study the homomorphic images. Moreover, we demonstrate an additional application of this automata model as we use it to describe the ranges of bottom-up and top-down weighted tree transformations.:1 Introduction 1.1 About this Work 1.2 Publications 2 Background 2.1 Preliminaries 2.1.1 Trees 2.1.2 Semirings 2.1.3 Tree Homomorphisms 2.2 Tree Automata and the HOM-Problem 3 Weighted Tree Automata with Constraints 3.1 The Model 3.2 Closure Properties 3.3 Hom-Regular Languages and the Subclass WTAh 3.4 Recognizing Homomorphic Images 3.5 A Pumping Lemma for WTAh 3.6 Conclusion 4 Unambiguity and the Weighted HOM-Problem 4.1 Translating TAh into TAhom 4.2 Deciding Regularity for Unambiguous WTAh 4.3 Unambiguity and the Instances of the HOM-Problem 4.4 Conclusion and Perspective 5 The N-Weighted HOM-Problem 5.1 The Large Duplication Property 5.2 Deciding the N-Weighted HOM-Problem 5.3 Conclusion 6 The HOM-Problem for Fields 6.1 Relating WTAh to WTA 6.2 A Pumping Lemma for WTAh over Fields 6.3 The Tetris-Free Weighted HOM-Problem 6.4 Conclusion 7 Weighted Tree Transducers in Light of Hom-Regular Tree Languages 7.1 Preliminaries: Transformations 7.2 Weighted Bottom-up Tree Transducers 7.2.1 Separating Weighted TOP and BOT – Part I 7.2.2 The Range of a Weighted Bottom-up Tree Transducer 7.3 Weighted Top-down Tree Transducers 7.3.1 Separating Weighted TOP and BOT – Part II 7.3.2 The Range of a Weighted Top-down Tree Transducer 7.4 Conclusion 8 Conclusion 8.1 Summary 8.2 FutureWork Bibliography Lebenslauf Selbständigkeitserklärung

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