Magíster en Ciencias de la Ingeniería, Mención Eléctrica / Ingeniero Civil Eléctrico / Tanto en ingeniería en minas como en astronomía existen problemas inversos en los cuales técnicas del procesamiento de señales juegan un rol importante al momento de procesar la información existente de manera óptima. En este trabajo de Tesis los problemas de clasifi- cación de texturas de roca y astronometría son abordados usando técnicas del procesamiento estadístico de señales. En ingeniería en minas es de gran importancia contar con una buena caracterización del subsuelo. Para ello diversas fuentes de información son utilizadas, encontrándose entre ellas la información visual de la textura de las rocas. Pese al amplio uso de estas fuentes para hacer inferencia del tipo de roca, no se ha logrado el desarrollo de técnicas de procesamiento computacional y automático que las implementen de manera exitosa. En este trabajo de tesis, seis clases de textura de roca son analizadas utilizando técnicas avanzadas del procesamiento de imágenes. Específicamente, para cada clase se propone la extracción de características especialmente diseñadas para esa clase. Las características propuestas ofrecen un alto poder discriminador y baja dimensionalidad. Adicionalmente, se propone un esquema de banco de detectores binarios con el fin de poner a prueba las características diseñadas. Finalmente, el desempeño de clasificación del método propuesto es comparado con métodos en el estado del arte de clasificación de texturas, mostrando ganancias importantes en cuanto a error de clasificación. El problema de astrometría corresponde a la determinación de la posición de astros me- diante dispositivos detectores, comúnmente CCDs (Charged Coupled Devices). Dichos dis- positivos presentan fuentes de ruido que afectan negativamente los métodos de localización. En este trabajo de tesis el método de mínimos cuadrados es analizado en detalle. En este contexto dicho método corresponde a un problema de regresión no lineal, por lo cual el desempeño o varianza del estimador resultante no puede ser caracterizado de manera aná- litica. Para ello se propone un método de aproximación de la varianza del estimador, que permite la comparación analítica con la cota de Cramér-Rao. Finalmente, análisis empíricos son desarrollados utilizando diversas configuraciones experimentales, encontrándose que, en determinadas condiciones de medición, el estimador es eficiente con respecto a la cota de Cramér-Rao.

We consider the smoothing problem for a class of conditionally linear Gaussian state-space (CLGSS) models, referred to as mixed linear/nonlinear models. In contrast to the better studied hierarchical CLGSS models, these allow for an intricate cross dependence between the linear and the nonlinear parts of the state vector. We derive a Rao-Blackwellized particle smoother (RBPS) for this model class by exploiting its tractable substructure. The smoother is of the forward filtering/backward simulation type. A key feature of the proposed method is that, unlike existing RBPS for this model class, the linear part of the state vector is marginalized out in both the forward direction and in the backward direction. / CNDM / CADICS

Prior to signal demodulation, blind recognition of the modulation scheme of the received signal is an important task for intelligent radios in various commercial and military applications such as spectrum management, surveillance of broadcasting activities and adaptive transmission. Antenna arrays provide spatial diversity and increase channel capacity. This thesis focuses on the algorithms and performance analysis of the blind modulation classification (MC) for a multiple antenna receiver configuration. For a single-input-multiple-output (SIMO) configuration with unknown channel amplitude, phase, and noise variance, we investigate likelihood-based algorithms for linear digital MC. The existing algorithms are presented and extended to SIMO. Using recently proposed blind estimates of the unknown parameters, a new algorithm is developed. In addition, two upper bounds on the classification performance of MC algorithms are provided. We derive the exact Cramer-Rao Lower Bounds (CRLBs) of joint estimates of the unknown parameters for one- and two-dimensional amplitude modulations. The asymptotic behaviors of the CRLBs are obtained for the high signal-to-noise-ratio (SNR) region. Numerical results demonstrate the accuracy of the CRLB expressions and confirm that the expressions in the literature are special cases of our results. The classification performance of the proposed algorithm is compared with the existing algorithm and upper bounds. It is shown that the proposed algorithm outperforms the existing one significantly with reasonable computational complexity. The proposed algorithm in this thesis can be used in modern intelligent radios equipped with multiple antenna receivers and the provided performance analysis, i.e., the CRLB expressions, can be employed to design practical systems involving estimation of the unknown parameters and is not limited to MC. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2012-09-21 00:51:43.938

Analysing migrating cells in microscopy time-lapse images has already helped the understanding of many biological processes and may be of importance in the development of new medical treatments. Today’s biological experiments tend to produce a huge amount of dynamic image data and tracking the individual cells by hand has become a bottleneck for the further analysis work. A number of cell tracking methods have therefore been developed over the past decades, but still many of the techniques have a limited performance. The aim of this Master Project is to develop a particle filter algorithm that automatically detects and tracks a large number of individual cells in an image sequence. The solution is based on a Rao-Blackwellized particle filter for multiple object tracking. The report also covers a review of existing automatic cell tracking techniques, a review of well-known filter techniques for single target tracking and how these techniques have been developed to handle multiple target tracking. The designed algorithm has been tested on real microscopy image data of neutrophils with 400 to 500 cells in each frame. The designed algorithm works well in areas of the images where no cells touch and can in these situations also correct for some segmentation mistakes. In areas where cells touch, the algorithm works well if the segmentation is correct, but often makes mistakes when it is not. A target effectiveness of 77 percent and a track purity of 80 percent are then achieved.

xi, 246 leaves : ill. ; 25 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1975) from the Dept. of English, University of Adelaide

Abstract In time delay estimation the correlator or, equivalently, matched filter estimator is widely used. Examples of its usage can be found in the global positioning system (GPS), radars and code division multiple access (CDMA) communication systems. Although widely used its performance is not studied in general case until recently. Partially this study is done in this thesis. If interfering signals like multipath or multiple access signals exist in addition to additive white Gaussian noise, as in GPS and CDMA, the correlator is not a maximum likelihood (ML) estimator. However, it is known that the correlator produces consistent estimates in the existence of multipath interference if the delay separation is larger than the correlation time of the signal (in direct sequence spread spectrum applications such as GPS and CDMA, the correlation time approximately equals the chip duration of the spreading code). It also performs well in the existence of multiple access interference (MAI), if the powers of the MAI signals are equal to the power of the desired signal. In this thesis the asymptotic distribution of the correlator estimator is derived in multisignal environments. Using the result, it can be analytically shown, that in these benign interference cases the exact ML estimator and the correlator estimators perform equally well in the sense that their asymptotic covariance matrices are equal. The thesis also verifies the well known result that if the signals are orthogonal, then the correlator and ML estimators perform equally. In addition, the correlator's asymptotic performance is investigated also in the inconsistent case by slightly extending the earlier results found in the literature. Also the resolution of the correlator estimator is investigated. It is numerically shown that the correlator estimator can produce consistent estimators even if the delay separation is less that the chip duration, which is commonly believed to be the resolution limit of the correlator. This can happen in fading channels where the multipath amplitudes are uncorrelated or just slightly correlated. This result seems to be fairly unknown. In addition to the classical ML estimator, where all the unknowns are assumed to be deterministic, also an improved ML estimator is investigated. This other ML estimator is obtained by assuming that the amplitudes are Gaussian distributed. It is an improved estimator in the sense that its asymptotic covariance, say CML, is less positive definite than that of the classical ML estimator CCML, i.e., CCML-CML is positive semidefinite. More importantly, this result is valid independent of the fact are the amplitudes really deterministic or Gaussian. This well known result is shown in this thesis to be valid also if the signals contain more than one unknown parameter, which occurs, for example, in direction-of-arrival estimation when two angles per arrival are to be estimated.

Asthma is a chronic disease of airway hyper-responsiveness, airway inflammation and episodic bronchoconstriction. With asthma forecasted to increase by an additional 100 million cases by 2025, there is a critical and immediate need to address new asthma therapies. Guidelines for asthma treatment in the emergency department conditionally recommend intravenous magnesium sulfate (MgSO4). However, some investigations have failed to demonstrate beneficial effects. Ethical constraints limit evaluation of the bronchodilatory effects of MgSO4 alone in patients with acute asthma exacerbation, independent of other conventional therapeutics. To address this ethical dilemma, this study consisted of two phases: 1) quantification of the independent pulmonary effect of three doubling doses of MgSO4 in the spontaneous equine model of asthma during naturally occurring exacerbations of bronchoconstriction, and 2) evaluation of arterial blood gas parameters in response to administration of MgSO4 at a dose identified in phase 1 that yielded greatest efficacy without deleterious side effects.

Pulmonary surfactant is synthesized in the alveoli and lines the respiratory epithelium of the airways. Phospholipids, the main component of surfactant, confer it its ability to lower surface tension and to prevent alveolar collapse. Airway surfactant helps maintain smaller airway patency, improves muco-ciliary clearance, decreases bronchoconstriction, and modulates pulmonary immunity. Surfactant alterations in human asthma are therefore believed to contribute to the severity of airway obstruction. The goal of our first study was to characterize surfactant phospholipid composition and function in healthy horses, and to investigate the influence of age and bronchoalveolar lavage fluid (BALF) sample characteristics on surfactant. For that purpose, BALF was collected from 17 healthy horses and evaluated for BALF recovery percentage, cell count, and cell differential. BALF was separated into crude surfactant pellets (CSP) and supernatant and was analyzed for phospholipid content, protein content, phospholipid composition, and surface tension. Interestingly, phospholipid (surfactant) content in CSP significantly decreased with age. BALF recovery percentage, nucleated cell count, and cytological profile did not affect surfactant composition or function. The hypothesis of our second study was that surfactant alterations in RAO-affected horses are related to clinical stage of RAO. The objectives were 1) to compare surfactant phospholipid composition and function between Non-RAO and RAO horses at clinical stages and 2) to investigate relationships between surfactant alterations and variables assessing clinical stage of RAO. Seven horses with confirmed RAO and seven Non-RAO horses were evaluated in pairs (RAO/Non-RAO) at baseline, during exposure to hay, and post-exposure. Assessments included: clinical scoring, measure of maximal change in pleural pressure (ΔPplmax), airway endoscopy, and BALF cell counts and differentials. Samples were processed and analyzed as described above. Phospholipid levels in BALF were significantly lower in RAO versus Non-RAO horses, even in the absence of clinical signs. In the group of RAO horses, phospholipid content was significantly lower during exposure versus baseline. Furthermore, exposure to hay led to an increase in the protein versus phospholipid ratio in BALF from RAO horses. No significant differences were found in BALF protein content, phospholipid composition, or surface tension between or within groups of horses. Phosphatidylglycerol percentage had a tendency to be lower in RAO horses with higher clinical scores. Supernatant protein content was related to BALF neutrophilia in RAO crisis and overall ΔPplmax . In conclusion, our study demonstrated that surfactant alterations in RAO horses are present in remission and are exacerbated following exposure to hay. It is conceivable that a lower amount of surfactant in bronchioli of RAO horses may contribute to the horses' propensity to develop airway obstruction, mucous accumulation, and bronchial hyperresponsiveness. This may be exacerbated during crisis by a relatively higher protein versus phospholipid ratio. Furthermore, a progressive decrease of surfactant levels in older horses may contribute to a worsening of clinical signs in older RAO-affected horses. / Ph. D.

La connaissance de l'environnement marin est nécessaire pour un grand nombre d'applications dans le domaine de l'acoustique sous-marine comme la communication, la localisation et détection sonar et la surveillance des mammifères marins. Il constitue le moyen principal pour éviter les interférences néfastes entre le milieu naturel et les actions industriels et militaires conduites en zones côtières.Notre travail de thèse se place dans un contexte de sonar actif avec des fréquences allant de 1 kHz à 10 kHz pour des distances de propagations allant de 1 km à plusieurs dizaines de kilomètres. Nous nous intéressons particulièrement aux environnements de propagation grands fonds, à l'utilisation des antennes industrielles comme les antennes de flancs, les antennes cylindriques et les antennes linéaires remorquées, et à l'utilisation de signaux large bande afin de travailler avec des résolutions en distance et en vitesse très élevées. Le travail de recherche présenté dans ce mémoire est dédié à la recherche de nouveaux paramètres discriminants pour la classification de cible sous-marine en sonar actif et notamment à l'estimation de l'immersion instantanée.Cette étude présente : (1) les calculs de nouvelles bornes de Cramer-Rao pour la position d'une cible en distance en et en profondeur, (2) l'estimation conjointe de la distance et de l'immersion d'une cible à partir de la mesure des temps d'arrivées et des angles d'élévations sur une antenne surfacique et (3) l'estimation conjointe de la distance, de l'immersion et du gisement d'une cible à partir de la mesure des temps d'arrivées et des pseudo-gisements sur une antenne linéaire remorquée.Les méthodes développées lors de cette étude ont été validées sur des simulations, des données expérimentales à petite échelle et des données réelles en mer. / The knowledge of the marine environment is required for many underwater applications such as communications, sonar localization and detection, and marine mammals monitoring. It enables preventing harmful interference between the natural environment and industrial and military actions in coastal areas.This thesis work concentrates upton the context of active sonar with frequencies from 1 kHz to 10 kHz and long propagation ranges from 1 km to several tens of kilometers. We also concentrates upon deep water environment, the use of industrial arrays such as cylindrical arrays, flank arrays and linear towed arrays, and the use of large time-bandwidth signals in order to obtain high distance and speed resolutions. This research work is dedicated to the research of new features for the underwater target classification in active sonar, and specifically to the instantaneous target-depth estimation.This thesis presents: (1) calculations of new Cramer-Rao bounds for the target-position in range and in depth, (2) the joint estimation of the target-depth and the target-range from the arrival time and elevation angle measures with a surface array, (3) the joint estimation of the target-depth, the target-range and the target-bearing from the arrival time and pseudo-bearing angle measures with a linear towed array.The methods presented in this manuscript have been benchmarked on simulation, on reduced-scale experimental data and real marine data.

No abstract available / Religious Studies / M.A. (Religious Studies)