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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.
251

Observatoire de trajectoire de piétons à l'aide d'un réseau de télémètre laser à balayage : application à l'intérieur des bâtiments / Pedestrian path monitoring using a scanning laser rangefinder network : application inside buildings

Adiaviakoye, Ladji 10 September 2015 (has links)
Dans la vie de tous les jours, nous assistons à des chorégraphies surprenantes dans les déplacements de foules de piétons. Les mécanismes qui sont à la base de la dynamique des foules humaines restent peu connus. Un des modes d’observation des piétons consiste à réaliser des mesures en conditions réelles (exemple : aéroport, gare, etc.). La trajectoire empruntée, la vitesse et l’accélération sont les données de base pour une telle analyse. C’est dans ce contexte que se placent nos travaux qui combinent étroitement observations en milieu naturel et expérimentations contrôlées. Nous avons proposé un système pour le suivi de plusieurs piétons dans un environnement fermé, à l’aide d’un réseau de télémètres lasers à balayage. Nous avons fait avancer l’état de l’art sur quatre plans.Premièrement, nous avons introduit une méthode de fusion automatique des données, permettant de discriminer les objets statiques (murs, poteaux, etc.) et aussi d’augmenter le taux de détection.Deuxièmement, nous avons proposé une méthode de détection non paramétrique basée sur la modélisation de la marche. L’algorithme estime la position du piéton, que celui-ci soit immobile ou en mouvement.Finalement, notre suivi repose sur la méthode Rao-Blackwell Monte Carlo Association de Données, avec la particularité de suivre un nombre variable de piétons.L’algorithme a été évalué quantitativement par des expériences de comportement social à différents niveaux de densité. Ces expériences ont eu lieu dans une école, près de 300 piétons ont été suivis dont une trentaine simultanément. / In everyday life, we witness surprising choreographies in the movements of crowds of pedestrians. The mechanisms that underlie the dynamics of human crowd dynamics remain poorly understood. One of the ways of observing pedestrians consists in taking measurements in real conditions (e. g. airport, station, etc.). The trajectory, speed and acceleration are the basic data for such an analysis. It is in this context that our work is placed, which closely combines observations in the natural environment with controlled experiments. We proposed a system for tracking multiple pedestrians in a closed environment using a network of scanning laser rangefinders. We have advanced the state of the art on four levels: first, we have introduced an automatic data fusion method to discriminate static objects (walls, poles, etc.) and also to increase the detection rate; second, we have proposed a non-parametric detection method based on walking modeling. The algorithm estimates the position of the pedestrian, whether stationary or moving, and finally, our monitoring is based on the Rao-Blackwell Monte Carlo Association Data Method, with the particularity of tracking a variable number of pedestrians, which was quantitatively evaluated by experiments in social behaviour at different levels of density. These experiments took place in a school, nearly 300 pedestrians were followed, about thirty of them simultaneously.
252

Caractérisation automatique d’organisations cellulaires dans des mosaïques d’images microscopiques de bois / Automatic characterization of the cell organization in light microscopic images of wood : application to the identification of the cell file

Brunel, Guilhem 01 October 2014 (has links)
Ce travail porte sur l'analyse d'images numériques biologiques. Il vise à définir et mettre en œuvre des processus de mesures automatiques de données biologiques à partir d'images numériques dans un cadre de traitement de masse, et aborde notamment : l'incidence des choix méthodologiques sur la stabilité des résultats, l'étude de la validation des mesures produites et les limites de la généricité des méthodes et modèles appliquées à la biologie végétale.La réflexion est menée dans le cadre de l'étude de certaines organisations cellulaires, et plus particulièrement de l'identification et l'analyse automatique de files cellulaires dans des mosaïques d'images microscopiques de bois. En effet, l'étude des tendances biologiques le long de ces structures est nécessaire pour comprendre la mise en place des différentes organisations et maturations de cellule. Elle ne peut être conduite qu'à partir d'une grande zone d'observation du plan ligneux. Pour cela,- nous avons mis en place un nouveau protocole de préparation (rondelles de bois poncées) et de numérisation des échantillons permettant d'acquérir entièrement la zone d'observation sans biais- nous avons développé une chaîne de traitement permettant l'extraction automatique des files cellulaires dans des mosaïques images numériques.- nous avons proposé des indices de fiabilité pour chaque mesure effectuée afin de mieux cibler les études statistiques à venir.Les méthodes développées dans la thèse permettent l'acquisition et le traitement rapide d'un volume important de données. Ces données devraient servir de base à de nombreuses investigations : des analyses architecturales des arbres avec le suivi de file cellulaire et/ou la détection de perturbations biologiques, des analyses de variabilité intra et inter arbres permettant de mieux comprendre la croissance endogène des arbres. / This study focuses on biological numeric picture processes. It aims to define and implement new automated measurements at large scale analysis. Moreover, this thesis addresses: The incidence of the proposed methodology on the results reliability measurements accuracy definition and analysis proposed approaches reproducibility limits when applied to plant biology.This work is part of cells organization study, and aims to automatically identify and analyze the cell lines in microscopic mosaic wood slice pictures. Indeed, the study of biological tendencies among the cells lines is necessary to understand the cell migration and organization. Such a study can only be realized from a huge zone of observation of wood plane. To this end, this work proposes:- a new protocol of preparation (slices of sanded wood) and of digitizing of samples, in order to acquire the entire zone of observation without bias,- a novel processing chain that permit the automated cell lines extraction in numeric mosaic pictures,- reliability indexes for each measurement for further efficient statistical analysis.The methods developed during this thesis enable to acquire and treat rapidly an important volume of information. Those data define the basis of numerous investigations, such as tree architectural analysis cell lines following and/or detection of biological perturbations. And it finally helps the analysis of the variability intra- or inter- trees, in order to better understand the tree endogenous growth.
253

Mesure et suivi d'activité de plusieurs personnes dans un Living Lab en vue de l'extraction d'indicateurs de santé et de bien-être / Activity measurement and monitoring of several people in a Living Lab in order to extract health and well being indicators

Sevrin, Loic 20 September 2016 (has links)
Le vieillissement de la population est un phénomène mondial qui s'accompagne d'une augmentation du nombre de patients atteints de maladies chroniques, ce qui oblige à repenser le système de santé en amenant le suivi de santé et les soins au domicile et dans la cité.En considérant que l'activité est un signe visible de l'état de santé, cette thèse cherche à proposer un moyen technologique pour le suivi des activités de plusieurs personnes dans un living lab composé d'un appartement et de la cité qui l'entoure.En effet, le maintien d'une activité physique soutenue, et en particulier d'une activité sociale fait partie intégrante de la bonne santé d'une personne, il doit donc être étudié au même titre que les capacités à effectuer les activités de la vie quotidienne.Cette étude a permis la mise en place d'une plateforme de conception collaborative et de test grandeur nature autour de la santé à domicile et dans la cité : le living lab de l'INL.Ce dernier a été le théâtre de premières expérimentations permettant de valider la capacité du living lab à la fois de fusionner des données d'activité venant d'un ensemble de capteurs hétérogènes, mais également d'évoluer en intégrant des nouvelles technologies et services.Les scénarios collaboratifs étudiés permettent une première approche de l'analyse de la collaboration par la détection des présences simultanées de plusieurs personnes dans la même pièce. Ces résultats préliminaires sont encourageants et seront complétés lors de captures d'activité plus fines et incluant plus de capteurs dans les mois à venir / The ageing of the population is a global phenomenon which comes with an increase of the amount of patients suffering from chronic diseases. It forces to rethink the healthcare by bringing health monitoring and care at home and in the city.Considering the activity as a visible indication of the health status, this thesis seeks to provide technological means to monitor several people's activities in a living lab composed of an apartment and the city around.Indeed, maintaining substantial physical activity, in particular social activity accounts fo an important part of a person's good health status. Hence, it must be studied as well as the ability to perform the activities of daily living.This study enabled the implementation of a platform for collaborative design and full-scale experimentation concerning healthcare at home and in the city: the INL living lab.The latest was the theatre of some first experimentations which highlighted the living lab ability to perform activity data fusion from a set of heterogeneous sensors, and also to evolve by integrating new technologies and services.The studied collaborative scenarios enable a first approach of the collaboration analysis by detecting the simultaneous presence of several people in the same room. These preliminary results are encouraging and will be completed by more precise measurements which will include more sensors in the coming months
254

Geographic Indexing and Data Management for 3D-Visualisation

Ottoson, Patrik January 2001 (has links)
No description available.
255

Automatic Bayesian Segmentation Of Human Facial Tissue Using 3d Mr-ct Fusion By Incorporating Models Of Measurement Blurring, Noise And Partial Volume

Sener, Emre 01 September 2012 (has links) (PDF)
Segmentation of human head on medical images is an important process in a wide array of applications such as diagnosis, facial surgery planning, prosthesis design, and forensic identification. In this study, a new Bayesian method for segmentation of facial tissues is presented. Segmentation classes include muscle, bone, fat, air and skin. The method incorporates a model to account for image blurring during data acquisition, a prior helping to reduce noise as well as a partial volume model. Regularization based on isotropic and directional Markov Random Field priors are integrated to the algorithm and their effects on segmentation accuracy are investigated. The Bayesian model is solved iteratively yielding tissue class labels at every voxel of an image. Sub-methods as variations of the main method are generated by switching on/off a combination of the models. Testing of the sub-methods are performed on two patients using single modality three-dimensional (3D) images as well as registered multi-modal 3D images (Magnetic Resonance and Computerized Tomography). Numerical, visual and statistical analyses of the methods are conducted. Improved segmentation accuracy is obtained through the use of the proposed image models and multi-modal data. The methods are also compared with the Level Set method and an adaptive Bayesiansegmentation method proposed in a previous study.
256

A gaming perspective on command and control

Brynielsson, Joel January 2006 (has links)
In emergency management and in military operations, command and control comprises the collection of functions, systems and staff personnel that one or several executives draw on to arrive at decisions and seeing that these decisions are carried out. The large amount of available information coupled with modern computers and computer networks brings along the potential for making well-informed and quick decisions. Hence, decision-making is a central aspect in command and control, emphasizing an obvious need for development of adequate decision-supporting tools to be used in command and control centers. However, command and control takes place in a versatile environment, including both humans and artifacts, making the design of useful computer tools both challenging and multi-faceted. This thesis deals with preparatory action in command and control settings with a focus on the strategic properties of a situation, i.e., to aid commanders in their operational planning activities with the utmost goal of ensuring that strategic interaction occurs under the most favorable circumstances possible. The thesis highlights and investigates the common features of interaction by approaching them broadly using a gaming perspective, taking into account various forms of strategic interaction in command and control. This governing idea, the command and control gaming perspective, is considered an overall contribution of the thesis. Taking the gaming perspective, it turns out that the area ought to be approached from several research directions. In particular, the persistent gap between theory and applications can be bridged by approaching the command and control gaming perspective using both an applied and a theoretical research direction. On the one hand, the area of game theory in conjunction with research findings stemming from artificial intelligence need to be modified to be of use in applied command and control settings. On the other hand, existing games and simulations need to be adapted further to take theoretical game models into account. Results include the following points: (1) classification of information with proposed measurements for a piece of information's precision, fitness for purpose and expected benefit, (2) identification of decision help and decision analysis as the two main directions for development of computerized tools in support of command and control, (3) development and implementation of a rule based algorithm for map-based decision analysis, (4) construction of an open source generic simulation environment to support command and control microworld research, (5) development of a generic tool for prediction of forthcoming troop movements using an algorithm stemming from particle filtering, (6) a non-linear multi-attribute utility function intended to take prevailing cognitive decision-making models into account, and (7) a framework based on game theory and influence diagrams to be used for command and control situation awareness enhancements. Field evaluations in cooperation with military commanders as well as game-theoretic computer experiments are presented in support of the results. / QC 20100825
257

Multisensor Segmentation-based Noise Suppression for Intelligibility Improvement in MELP Coders

Demiroglu, Cenk 18 January 2006 (has links)
This thesis investigates the use of an auxiliary sensor, the GEMS device, for improving the quality of noisy speech and designing noise preprocessors to MELP speech coders. Use of auxiliary sensors for noise-robust ASR applications is also investigated to develop speech enhancement algorithms that use acoustic-phonetic properties of the speech signal. A Bayesian risk minimization framework is developed that can incorporate the acoustic-phonetic properties of speech sounds and knowledge of human auditory perception into the speech enhancement framework. Two noise suppression systems are presented using the ideas developed in the mathematical framework. In the first system, an aharmonic comb filter is proposed for voiced speech where low-energy frequencies are severely suppressed while high-energy frequencies are suppressed mildly. The proposed system outperformed an MMSE estimator in subjective listening tests and DRT intelligibility test for MELP-coded noisy speech. The effect of aharmonic comb filtering on the linear predictive coding (LPC) parameters is analyzed using a missing data approach. Suppressing the low-energy frequencies without any modification of the high-energy frequencies is shown to improve the LPC spectrum using the Itakura-Saito distance measure. The second system combines the aharmonic comb filter with the acoustic-phonetic properties of speech to improve the intelligibility of the MELP-coded noisy speech. Noisy speech signal is segmented into broad level sound classes using a multi-sensor automatic segmentation/classification tool, and each sound class is enhanced differently based on its acoustic-phonetic properties. The proposed system is shown to outperform both the MELPe noise preprocessor and the aharmonic comb filter in intelligibility tests when used in concatenation with the MELP coder. Since the second noise suppression system uses an automatic segmentation/classification algorithm, exploiting the GEMS signal in an automatic segmentation/classification task is also addressed using an ASR approach. Current ASR engines can segment and classify speech utterances in a single pass; however, they are sensitive to ambient noise. Features that are extracted from the GEMS signal can be fused with the noisy MFCC features to improve the noise-robustness of the ASR system. In the first phase, a voicing feature is extracted from the clean speech signal and fused with the MFCC features. The actual GEMS signal could not be used in this phase because of insufficient sensor data to train the ASR system. Tests are done using the Aurora2 noisy digits database. The speech-based voicing feature is found to be effective at around 10 dB but, below 10 dB, the effectiveness rapidly drops with decreasing SNR because of the severe distortions in the speech-based features at these SNRs. Hence, a novel system is proposed that treats the MFCC features in a speech frame as missing data if the global SNR is below 10 dB and the speech frame is unvoiced. If the global SNR is above 10 dB of the speech frame is voiced, both MFCC features and voicing feature are used. The proposed system is shown to outperform some of the popular noise-robust techniques at all SNRs. In the second phase, a new isolated monosyllable database is prepared that contains both speech and GEMS data. ASR experiments conducted for clean speech showed that the GEMS-based feature, when fused with the MFCC features, decreases the performance. The reason for this unexpected result is found to be partly related to some of the GEMS data that is severely noisy. The non-acoustic sensor noise exists in all GEMS data but the severe noise happens rarely. A missing data technique is proposed to alleviate the effects of severely noisy sensor data. The GEMS-based feature is treated as missing data when it is detected to be severely noisy. The combined features are shown to outperform the MFCC features for clean speech when the missing data technique is applied.
258

Variation modeling, analysis and control for multistage wafer manufacturing processes

Jin, Ran 10 May 2011 (has links)
Geometric quality variables of wafers, such as BOW and WARP, are critical in their applications. A large variation of these quality variables reduces the number of conforming products in the downstream production. Therefore, it is important to reduce the variation by variation modeling, analysis and control for multistage wafer manufacturing processes (MWMPs). First, an intermediate feedforward control strategy is developed to adjust and update the control actions based on the online measurements of intermediate wafer quality measurements. The control performance is evaluated in a MWMP to transform ingots into polished wafers. However, in a complex multistage manufacturing process, the quality variables may have nonlinear relationship with the parameters of the predictors. In this case, piecewise linear regression tree (PLRT) models are used to address nonlinear relationships in MWMP to improve the model prediction performance. The obtained PLRT model is further reconfigured to be complied with the physical layout of the MWMP for feedforward control purposes. The procedure and effectiveness of the proposed method is shown in a case study of a MWMP. Furthermore, as the geometric profiles and quality variables are important quality features for a wafer, fast and accurate measurements of those features are crucial for variation reduction and feedforward control. A sequential measurement strategy is proposed to reduce the number of samples measured in a wafer, yet provide adequate accuracy for the quality feature estimation. A Gaussian process model is used to estimate the true profile of a wafer with improved sensing efficiency. Finally, we study the multistage multimode process monitoring problem. We propose to use PLRTs to inter-relate the variables in a multistage multimode process. A unified charting system is developed. We further study the run length distribution, and optimize the control chart system by considering the modeling uncertainties. Finally, we compare the proposed method with the risk adjustment type of control chart systems based on global regression models, for both simulation study and a wafer manufacturing process.
259

Geographic Indexing and Data Management for 3D-Visualisation

Ottoson, Patrik January 2001 (has links)
No description available.
260

Bayesian 3D multiple people tracking using multiple indoor cameras and microphones

Lee, Yeongseon. January 2009 (has links)
Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Rusell M. Mersereau; Committee Member: Biing Hwang (Fred) Juang; Committee Member: Christopher E. Heil; Committee Member: Georgia Vachtsevanos; Committee Member: James H. McClellan. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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