Дисертації з теми "Data localisation"
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Romero, Marcelo. "Landmark localisation in 3D face data." Thesis, University of York, 2010. http://etheses.whiterose.ac.uk/1147/.
Повний текст джерелаNelson, Peter. "Driven by data : city-scale localisation at night." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:d67f91ea-5a9c-47b3-be07-7a46875ed503.
Повний текст джерелаFarchi, Alban. "On the localisation of ensemble data assimilation methods." Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC1034.
Повний текст джерелаData assimilation is the mathematical discipline which gathers all the methods designed to improve the knowledge of the state of a dynamical system using both observations and modelling results of this system. In the geosciences, data assimilation it mainly applied to numerical weather prediction. It has been used in operational centres for several decades, and it has significantly contributed to the increase in quality of the forecasts.Ensemble methods are powerful tools to reduce the dimension of the data assimilation systems. Currently, the two most widespread classes of ensemble data assimilation methods are the ensemble Kalman filter (EnKF) and the particle filter (PF). The success of the EnKF in high-dimensional geophysical systems is largely due to the use of localisation. Localisation is based on the assumption that correlations between state variables in a dynamical system decrease at a fast rate with the distance. In this thesis, we have studied and improved localisation methods for ensemble data assimilation.The first part is dedicated to the implementation of localisation in the PF. The recent developments in local particle filtering are reviewed, and a generic and theoretical classification of local PF algorithms is introduced, with an emphasis on the advantages and drawbacks of each category. Alongside the classification, practical solutions to the difficulties of local particle filtering are suggested. The local PF algorithms are tested and compared using twin experiments with low- to medium-order systems. Finally, we consider the case study of the prediction of the tropospheric ozone using concentration measurements. Several data assimilation algorithms, including local PF algorithms, are applied to this problem and their performances are compared.The second part is dedicated to the implementation of covariance localisation in the EnKF. We show how covariance localisation can be efficiently implemented in the deterministic EnKF using an augmented ensemble. The proposed algorithm is tested using twin experiments with a medium-order model and satellite-like observations. Finally, the consistency of the deterministic EnKF with covariance localisation is studied in details. A new implementation is proposed and compared to the original one using twin experiments with low-order models
Engin, Zeynep. "Biologically plausible pattern localisation and parameter estimation on visual data." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511987.
Повний текст джерелаZaman, Munir uz. "Mobile robot localisation : error modelling, data synchronisation and vision techniques." Thesis, University of Surrey, 2006. http://epubs.surrey.ac.uk/844082/.
Повний текст джерелаStrumia, Maddalena [Verfasser], and Thomas [Akademischer Betreuer] Brox. "Localisation and characterisation of brain pathology from structural MRI data." Freiburg : Universität, 2016. http://d-nb.info/1122594186/34.
Повний текст джерелаJagbrant, Gustav. "Autonomous Crop Segmentation, Characterisation and Localisation." Thesis, Linköpings universitet, Institutionen för systemteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-97374.
Повний текст джерелаEftersom fruktodlingar kräver stora markområden är de ofta belägna långt från större befolkningscentra. Detta gör det svårt att finna tillräckligt med arbetskraft och begränsar expansionsmöjligheterna. Genom att integrera autonoma robotar i drivandet av odlingarna skulle arbetet kunna effektiviseras och behovet av arbetskraft minska. Ett nyckelproblem för alla autonoma robotar är lokalisering; hur vet roboten var den är? I jordbruksrobotar är standardlösningen att använda GPS-positionering. Detta är dock problematiskt i fruktodlingar, då den höga och täta vegetationen begränsar användandet till större robotar som når ovanför omgivningen. För att möjliggöra användandet av mindre robotar är det istället nödvändigt att använda ett GPS-oberoende lokaliseringssystem. Detta problematiseras dock av den likartade omgivningen och bristen på distinkta riktpunkter, varför det framstår som osannolikt att existerande standardlösningar kommer fungera i denna omgivning. Därför presenterar vi ett GPS-oberoende lokaliseringssystem, speciellt riktat mot fruktodlingar, som utnyttjar den naturliga strukturen hos omgivningen.Därutöver undersöker vi och utvärderar tre relaterade delproblem. Det föreslagna systemet använder ett 3D-punktmoln skapat av en 2D-LIDAR och robotens rörelse. Först visas hur en dold semi-markovmodell kan användas för att segmentera datasetet i enskilda träd. Därefter introducerar vi ett antal deskriptorer för att beskriva trädens geometriska form. Vi visar därefter hur detta kan kombineras med en dold markovmodell för att skapa ett robust lokaliseringssystem.Slutligen föreslår vi en metod för att detektera segmenteringsfel när nya mätningar av träd associeras med tidigare uppmätta träd. De föreslagna metoderna utvärderas individuellt och visar på goda resultat. Den föreslagna segmenteringsmetoden visas vara noggrann och ge upphov till få segmenteringsfel. Därutöver visas att de introducerade deskriptorerna är tillräckligt konsistenta och informativa för att möjliggöra lokalisering. Ytterligare visas att den presenterade lokaliseringsmetoden är robust både mot brus och segmenteringsfel. Slutligen visas att en signifikant majoritet av alla segmenteringsfel kan detekteras utan att felaktigt beteckna korrekta segmenteringar som inkorrekta.
Graham, Caroline C. "Scale model seismicity : a detailed study of deformation localisation from laboratory acoustic emission data." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4654.
Повний текст джерелаDanielsson, Simon, and Jakob Flygare. "A Multi-Target Graph-Constrained HMM Localisation Approach using Sparse Wi-Fi Sensor Data." Thesis, KTH, Optimeringslära och systemteori, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231090.
Повний текст джерелаI det här examensarbetet har lokalisering av gångtrafikanter med hjälp av Hidden Markov Models utförts. Lokaliseringen är byggd på data från Wi-Fi sensorer i ett område i Stockholm. Området är modellerat som ett graf-baserat nätverk där linjerna mellan noderna representerar möjliga vägar för en person att befinna sig på. Resultatet för varje individ är aggregerat för att visa förväntat antal personer på varje segment över en hel dag. Två metoder för att analysera hur event påverkar området introduceras och beskrivs. Den första är baserad på tidsserieanalys och den andra är en maskinlärningsmetod som bygger på Baum-Welch algoritmen. Båda metoderna visar vilka segment som drabbas mest av en snabb ökning av trafik i området och var trängsel är troligt att förekomma.
Ahmed, Bacha Adda Redouane. "Localisation multi-hypothèses pour l'aide à la conduite : conception d'un filtre "réactif-coopératif"." Thesis, Evry-Val d'Essonne, 2014. http://www.theses.fr/2014EVRY0051/document.
Повний текст джерела“ When we use information from one source,it's plagiarism;Wen we use information from many,it's information fusion ”This work presents an innovative collaborative data fusion approach for ego-vehicle localization. This approach called the Optimized Kalman Particle Swarm (OKPS) is a data fusion and an optimized filtering method. Data fusion is made using data from a low cost GPS, INS, Odometer and a Steering wheel angle encoder. This work proved that this approach is both more appropriate and more efficient for vehicle ego-localization in degraded sensors performance and highly nonlinear situations. The most widely used vehicle localization methods are the Bayesian approaches represented by the EKF and its variants (UKF, DD1, DD2). The Bayesian methods suffer from sensitivity to noises and instability for the highly non-linear cases. Proposed for covering the Bayesian methods limitations, the Multi-hypothesis (particle based) approaches are used for ego-vehicle localization. Inspired from monte-carlo simulation methods, the Particle Filter (PF) performances are strongly dependent on computational resources. Taking advantages of existing localization techniques and integrating metaheuristic optimization benefits, the OKPS is designed to deal with vehicles high nonlinear dynamic, data noises and real time requirement. For ego-vehicle localization, especially for highly dynamic on-road maneuvers, a filter needs to be robust and reactive at the same time. The OKPS filter is a new cooperative-reactive localization algorithm inspired by dynamic Particle Swarm Optimization (PSO) metaheuristic methods. It combines advantages of the PSO and two other filters: The Particle Filter (PF) and the Extended Kalman filter (EKF). The OKPS is tested using real data collected using a vehicle equipped with embedded sensors. Its performances are tested in comparison with the EKF, the PF and the Swarm Particle Filter (SPF). The SPF is an interesting particle based hybrid filter combining PSO and particle filtering advantages; It represents the first step of the OKPS development. The results show the efficiency of the OKPS for a high dynamic driving scenario with damaged and low quality GPS data
Nowakowski, Mathieu. "Localisation d'un robot humanoïde en milieu intérieur non-contraint." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEM026/document.
Повний текст джерелаAfter the democratization of industrial robots, the current trend is the development of social robots that create strong interactions with their users. The deployment of such platforms in shops, museums or train stations raises various issues including the autonomous localization of mobile robots. This thesis focuses on the localization of Pepper robots in a non-constrained indoor environment. Pepper robots are daily used in many shops in Japan and must be as autonomous as possible. However, localization solutions in the literature suffer from the limitations of the platform. This thesis is split into two main themes. First, the problem of relocalization in a visually redundant environment is studied. The proposed solution combines vision and Wi-Fi in a probabilistic approach based on the appearance. Then, the question of a consistent metrical mapping is examined. In order to compensate the numerous losses of tracking caused by the low acquisition frequency, odometric constraints are added to a bundle adjustment optimization. These solutions have been tested and validated on several Pepper robots, from data collected in different indoor environments over more than 7 km
ANDREOLETTI, Pierre. "Localisation et Concentration de la Marche de Sinai." Phd thesis, Université de la Méditerranée - Aix-Marseille II, 2003. http://tel.archives-ouvertes.fr/tel-00004116.
Повний текст джерелаWelte, Anthony. "Spatio-temporal data fusion for intelligent vehicle localization." Thesis, Compiègne, 2020. http://bibliotheque.utc.fr/EXPLOITATION/doc/IFD/2020COMP2572.
Повний текст джерелаLocalization is an essential basic capability for vehicles to be able to navigate autonomously on the road. This can be achieved through already available sensors and new technologies (Iidars, smart cameras). These sensors combined with highly accurate maps result in greater accuracy. In this work, the benefits of storing and reusing information in memory (in data buffers) are explored. Localization systems need to perform a high-frequency estimation, map matching, calibration and error detection. A framework composed of several processing layers is proposed and studied. A main filtering layer estimates the vehicle pose while other layers address the more complex problems. High-frequency state estimation relies on proprioceptive measurements combined with GNSS observations. Calibration is essential to obtain an accurate pose. By keeping state estimates and observations in a buffer, the observation models of these sensors can be calibrated. This is achieved using smoothed estimates in place of a ground truth. Lidars and smart cameras provide measurements that can be used for localization but raise matching issues with map features. In this work, the matching problem is addressed on a spatio-temporal window, resulting in a more detailed pictur of the environment. The state buffer is adjusted using the observations and all possible matches. Although using mapped features for localization enables to reach greater accuracy, this is only true if the map can be trusted. An approach using the post smoothing residuals has been developed to detect changes and either mitigate or reject the affected features
Héry, Elwan. "Localisation coopérative de véhicules autonomes communicants." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2516.
Повний текст джерелаTo be able to navigate autonomously, a vehicle must be accurately localized relatively to all obstacles, such as roadside for lane keeping and vehicles and pedestrians to avoid causing accidents. This PhD thesis deals with the interest of cooperation to improve the localization of cooperative vehicles that exchange information. Autonomous navigation on the road is often based on coordinates provided in a Cartesian frame. In order to better represent the pose of a vehicle with respect to the lane in which it travels, we study curvilinear coordinates with respect to a path stored in a map. These coordinates generalize the curvilinear abscissa by adding a signed lateral deviation from the center of the lane and an orientation relative to the center of the lane taking into account the direction of travel. These coordinates are studied with different track models and using different projections to make the map-matching. A first cooperative localization approach is based on these coordinates. The lateral deviation and the orientation relative to the lane can be known precisely from a perception of the lane borders, but for autonomous driving with other vehicles, it is important to maintain a good longitudinal accuracy. A one-dimensional data fusion method makes it possible to show the interest of the cooperative localization in this simplified case where the lateral deviation, the curvilinear orientation and the relative positioning between two vehicles are accurately known. This case study shows that, in some cases, lateral accuracy can be propagated to other vehicles to improve their longitudinal accuracy. The correlation issues of the errors are taken into account with a covariance intersection filter. An ICP (Iterative Closest Point) minimization algorithm is then used to determine the relative pose between the vehicles from LiDAR points and a 2D polygonal model representing the shape of the vehicle. Several correspondences of the LiDAR points with the model and different minimization approaches are compared. The propagation of absolute vehicle pose using relative poses with their uncertainties is done through non-linear equations that can have a strong impact on consistency. The different dynamic elements surrounding the ego-vehicle are estimated in a Local Dynamic Map (LDM) to enhance the static high definition map describing the center of the lane and its border. In our case, the agents are only communicating vehicles. The LDM is composed of the state of each vehicle. The states are merged using an asynchronous algorithm, fusing available data at variable times. The algorithm is decentralized, each vehicle computing its own LDM and sharing it. As the position errors of the GNSS receivers are biased, a marking detection is introduced to obtain the lateral deviation from the center of the lane in order to estimate these biases. LiDAR observations with the ICP method allow to enrich the fusion with the constraints between the vehicles. Experimental results of this fusion show that the vehicles are more accurately localized with respect to each other while maintaining consistent poses
Joubert, Deon. "Saliency grouped landmarks for use in vision-based simultaneous localisation and mapping." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/40834.
Повний текст джерелаDissertation (MEng)--University of Pretoria, 2013.
gm2014
Electrical, Electronic and Computer Engineering
unrestricted
Laby, Romain. "Détection et localisation d'anomalies dans des données hétérogènes en utilisant des modèles graphiques non orientés mixtes." Electronic Thesis or Diss., Paris, ENST, 2017. http://www.theses.fr/2017ENST0026.
Повний текст джерелаThis thesis revolves around an industrial need of Thales Système Aéroportés and the RBE2 combat radar equipping Dassault Rafale fighter aircraft. It develops a methodology for locating anomalies in heterogeneous data stream using a mixed, non-orientation and peer-to-peer graphical model. The data are a mixture of categorical and quantitative variables, and the model is learned from a data set that is assumed not to contain abnormal data. Anomaly localization algorithms use an adapted version of the CUSUM algorithm, whose decision function is based on the calculation of conditional likelihood ratios. This function allows the detection of variable anomalies per variable and the precise localization of the variables involved in the anomaly
Okeya, Olanrewaju Isaac. "Detection and localisation of pipe bursts in a district metered area using an online hydraulic model." Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/33823.
Повний текст джерелаKueviakoe, Kangni. "Localisation multi-capteurs garantie : résolution d'un problème de satisfaction de contraintes." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112241/document.
Повний текст джерелаThis thesis deals with the vehicle locationand addresses the problem of SLAM (simultaneous localization and mapping). Several methods are used to solve this kind of problem. They can be classified into two broad categories of approaches: probabilistic approach and deterministic approaches. This work addresses the deterministic approaches and more precisely the approach based on interval analysis. The work has been conducted on real data sets collected in outdoor environments with proprioceptive and exteroceptive sensors.When multiple sensors providing complementary or redundant information are put into play, it is important to merge the data to improve the estimated pose. The approach detailed in this document uses the intervals methods and presents the localization problem as a constraint satisfaction problem.The resolution is done using a solver interval. Several solvers were compared. One thing is clear: local consistency algorithms do not address the uncertainty of the orientation. This thesis proposes a method of locating usable in real time applications and corrects the uncertainty in the heading of the vehicle. We compared our results with those of the extended Kalman filter (probabilistic reference method) and highlighted one of the interests of our method: the assurance of consistency of the pose (position and orientation of the mobile).This thesis proposes two contributions. The first is methodological. In the state of the art all works affirm the need (or obligation) to pre-decompose the constraints of the problem before the resolution step. Our work allows to prove otherwise. The second contribution relates to the reduction of the orientation uncertainty by combining constraint propagation and a bisection approach
Lassoued, Khaoula. "Localisation de robots mobiles en coopération mutuelle par observation d'état distribuée." Thesis, Compiègne, 2016. http://www.theses.fr/2016COMP2289/document.
Повний текст джерелаIn this work, we study some cooperative localization issues for mobile robotic systems that interact with each other without using relative measurements (e.g. bearing and relative distances). The considered localization technologies are based on beacons or satellites that provide radio-navigation measurements. Such systems often lead to offsets between real and observed positions. These systematic offsets (i.e, biases) are often due to inaccurate beacon positions, or differences between the real electromagnetic waves propagation and the observation models. The impact of these biases on robots localization should not be neglected. Cooperation and data exchange (estimates of biases, estimates of positions and proprioceptive measurements) reduce significantly systematic errors. However, cooperative localization based on sharing estimates is subject to data incest problems (i.e, reuse of identical information in the fusion process) that often lead to over-convergence problems. When position information is used in a safety-critical context (e.g. close navigation of autonomous robots), one should check the consistency of the localization estimates. In this context, we aim at characterizing reliable confidence domains that contain robots positions with high reliability. Hence, set-membership methods are considered as efficient solutions. This kind of approach enables merging adequately the information even when it is reused several time. It also provides reliable domains. Moreover, the use of non-linear models does not require any linearization. The modeling of a cooperative system of nr robots with biased beacons measurements is firstly presented. Then, we perform an observability study. Two cases regarding the localization technology are considered. Observability conditions are identified and demonstrated. We then propose a set-membership method for cooperativelocalization. Cooperation is performed by sharing estimated positions, estimated biases and proprioceptive measurements. Sharing biases estimates allows to reduce the estimation error and the uncertainty of the robots positions. The algorithm feasibility is validated through simulation when the observations are beacons distance measurements with several robots. The cooperation provides better performance compared to a non-cooperative method. Afterwards, the cooperative algorithm based on set-membership method is tested using real data with two experimental vehicles. Finally, we compare the interval method performance with a sequential Bayesian approach based on covariance intersection. Experimental results indicate that the interval approach provides more accurate positions of the vehicles with smaller confidence domains that remain reliable. Indeed, the comparison is performed in terms of accuracy and uncertainty
Vincke, Bastien. "Architectures pour des systèmes de localisation et de cartographie simultanées." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00770323.
Повний текст джерелаBalakrishnan, Arjun. "Integrity Analysis of Data Sources in Multimodal Localization System." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASG060.
Повний текст джерелаIntelligent vehicles are a key component in humanity’s vision for safer, efficient, and accessible transportation systems across the world. Due to the multitude of data sources and processes associated with Intelligent vehicles, the reliability of the total system is greatly dependent on the possibility of errors or poor performances observed in its components. In our work, we focus on the critical task of localization of intelligent vehicles and address the challenges in monitoring the integrity of data sources used in localization. The primary contribution of our research is the proposition of a novel protocol for integrity by combining integrity concepts from information systems with the existing integrity concepts in the field of Intelligent Transport Systems (ITS). An integrity monitoring framework based on the theorized integrity protocol that can handle multimodal localization problems is formalized. As the first step, a proof of concept for this framework is developed based on cross-consistency estimation of data sources using polynomial models. Based on the observations from the first step, a 'Feature Grid' data representation is proposed in the second step and a generalized prototype for the framework is implemented. The framework is tested in highways as well as complex urban scenarios to demonstrate that the proposed framework is capable of providing continuous integrity estimates of multimodal data sources used in intelligent vehicle localization
Karlsson, Anders, and Jon Bjärkefur. "Simultaneous Localisation and Mapping of Indoor Environments Using a Stereo Camera and a Laser Camera." Thesis, Linköpings universitet, Institutionen för systemteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-64447.
Повний текст джерелаPelassa, Véronique. "Détection, localisation et étude des propriétés spectrales de sursauts gamma observés à haute énergie avec l'expérience Fermi." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20161/document.
Повний текст джерелаGamma-Ray Bursts (GRB) are among the brightest gamma-ray sources in the sky. The current standard framework associates their prompt gamma-ray emission to charged particles accelerated in relativistic jets issued by newly-formed stellar-mass black holes. The radio to X-ray afterglow emission is due to the interaction between these jets and the interstellar medium.The LAT, pair-creation instrument onboard Fermi gamma-ray space telescope, performs unprecedented observation of the gamma-ray sky at energies of 20 MeV to over 300 GeV since its launch in june 2008. Fermi's transient sources detector, GBM, observed prompt emissions of ~450 GRB between 8 keV and 40 MeV. ~18 of these GRB were also studied up to GeV energies with the LAT. Accurate GRB localizations and Fermi's synergy with other observatories allows the study of GRB afterglows, and therefore a better interpretation of these observations.The analyses of GRB emissions between 8 keV to GeV energies is presented here. Localizations based on LAT data and their biases are studied. Spectral analyses of combined GBM and LAT data are shown, and their theoretical interpretations explained.An alternative analysis based on a relaxed selection of LAT data is presented and fully characterized. It allows to recover and use low-energy LAT statistics in temporal and spectral analyses of GRB prompt emission.Searches for long-lived high-energy emission from GRB are presented. The analysis of GRB 090510 afterglow emission from eV to GeV energies is described.Finally, Fermi bright GRB prompt emissions are compared to an internal shock model developed at IAP
Courcoux-Caro, Milan. "Conception optimisée d’antenne pour de la localisation passive de sources acoustiques." Thesis, Brest, École nationale supérieure de techniques avancées Bretagne, 2022. http://www.theses.fr/2022ENTA0001.
Повний текст джерелаThe objective of this thesis work is to propose an approach of array design for the localization of aerial or underwater acoustic sources. First, we will see how to describe the propagation of waves emitted by the sources. Then we will draw up the different methods allowing to estimate the positions of the sources from the measurements acquired by the sensors and from the propagation model. The bibliographic work on the field of acoustic source localization will highlight the importance of the sensors’ positions in the performance of the source position estimators. This will lead to a second bibliographic work on antenna design, and more precisely on the selection of sensor positions. The state of the art on antenna design methods will allow us to propose the following method: a sequential Bayesian data-driven selection. This approach takes into account the information contained in the measurements previously acquired in the pre-designed antenna, in order to select the future sensors. The application of this approach is innovative in the context of acoustic source localization. In a second step, first results realized on synthetic data prove to be promising for the application of this approach in an underwater acoustic source localization context. The analyses provided in this manuscript will allow to judge the relevance of this approach in the tested context, as well as to evaluate and compare the performance of this antenna design with the literature. Finally, we will apply this approach on real data from an experiment set up during the thesis. The propagation environment will be aerial in a closed reverberant room with a large number of available sensors. Acquiring real data will allow, in addition to evaluating the performance of our approach, to provide a new antenna design. This is designed from synthetic data and then applied to real data
Essouayed, Elyess. "Développement d'une stratégie de localisation d'une source de contaminants en nappe : mesures innovantes et modélisation inverse." Thesis, Bordeaux 3, 2019. http://www.theses.fr/2019BOR30006/document.
Повний текст джерелаContaminated sites management and remediation can be complex and require a significant investment to locate the contaminant source, which delivers the higher pollutant mass fluxes. The study proposes a strategy for contaminant source localisation using in situ measurement and inverse modelling. First, an innovative tool was developed to measure groundwater velocity in a well. The developed tool called DVT (Direct Velocity Tool) made it possible to measure a low Darcy flux. Laboratory and field tests were performed with the DVT and compared to other velocity measurement tools. By combining the DVT with a local concentration measurement, it is possible to calculate the mass fluxes passing through wells. Then the thesis present the inverse modeling used for source localisation and parameters estimation. The study was done on two synthetics cases using the non-linear optimisation method. To adapt the method to a real management of polluted sites, an iterative strategy is developed by imposing a limited addition of new observations to each modeling phase. This strategy is base on the Data Worth approach. Source localisation results on the two synthetic cases made it possible to judge the method applicability to a real site problem. The source localisation strategy is then applied to a real site with (i) mass flux measurement with velocities (DVT) and concentrations and (ii) inverse modeling. The modeling phases made it possible to locate the new wells and helped the source localisation. Nevertheless, by analysing the results more precisely, the hydraulic conductivity field estimated by the optimisation did not correspond to reality. In addition, contaminant mass fluxes highlightes two distinct zones of flux. By analysing the pollutant ratio of the site, it appears that two plumes are potentially present. Thus, another inverse modeling phase has been tested (i) to locate the two potential sources and (ii) to estimate the chemistry of the site. Results of the strategy were compared to the geoprobe campaign which confirmed the second source location
Dine, Abdelhamid. "Localisation et cartographie simultanées par optimisation de graphe sur architectures hétérogènes pour l’embarqué." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS303/document.
Повний текст джерелаSimultaneous Localization And Mapping is the process that allows a robot to build a map of an unknown environment while at the same time it determines the robot position on this map.In this work, we are interested in graph-based SLAM method. This method uses a graph to represent and solve the SLAM problem. A graph optimization consists in finding a graph configuration (trajectory and map) that better matches the constraints introduced by the sensors measurements. Graph optimization is characterized by a high computational complexity that requires high computational and memory resources, particularly to explore large areas. This limits the use of graph-based SLAM in real-time embedded systems. This thesis contributes to the reduction of the graph-based computational complexity. Our approach is based on two complementary axes: data representation in memory and implementation on embedded heterogeneous architectures. In the first axis, we propose an incremental data structure to efficiently represent and then optimize the graph. In the second axis, we explore the use of the recent heterogeneous architectures to speed up graph-based SLAM. We propose an efficient implementation model for embedded applications. We highlight the advantages and disadvantages of the evaluated architectures, namely GPU-based and FPGA-based System-On-Chips
Awang, Salleh Dayang Nur Salmi Dharmiza. "Study of vehicle localization optimization with visual odometry trajectory tracking." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS601.
Повний текст джерелаWith the growing research on Advanced Driver Assistance Systems (ADAS) for Intelligent Transport Systems (ITS), accurate vehicle localization plays an important role in intelligent vehicles. The Global Positioning System (GPS) has been widely used but its accuracy deteriorates and susceptible to positioning error due to factors such as the restricting environments that results in signal weakening. This problem can be addressed by integrating the GPS data with additional information from other sensors. Meanwhile, nowadays, we can find vehicles equipped with sensors for ADAS applications. In this research, fusion of GPS with visual odometry (VO) and digital map is proposed as a solution to localization improvement with low-cost data fusion. From the published works on VO, it is interesting to know how the generated trajectory can further improve vehicle localization. By integrating the VO output with GPS and OpenStreetMap (OSM) data, estimates of vehicle position on the map can be obtained. The lateral positioning error is reduced by utilizing lane distribution information provided by OSM while the longitudinal positioning is optimized with curve matching between VO trajectory trail and segmented roads. To observe the system robustness, the method was validated with KITTI datasets tested with different common GPS noise. Several published VO methods were also used to compare improvement level after data fusion. Validation results show that the positioning accuracy achieved significant improvement especially for the longitudinal error with curve matching technique. The localization performance is on par with Simultaneous Localization and Mapping (SLAM) SLAM techniques despite the drift in VO trajectory input. The research on employability of VO trajectory is extended for a deterministic task in lane-change detection. This is to assist the routing service for lane-level direction in navigation. The lane-change detection was conducted by CUSUM and curve fitting technique that resulted in 100% successful detection for stereo VO. Further study for the detection strategy is however required to obtain the current true lane of the vehicle for lane-level accurate localization. With the results obtained from the proposed low-cost data fusion for localization, we see a bright prospect of utilizing VO trajectory with information from OSM to improve the performance. In addition to obtain VO trajectory, the camera mounted on the vehicle can also be used for other image processing applications to complement the system. This research will continue to develop with future works concluded in the last chapter of this thesis
Avril, Arnaud. "Isolement de fragments d'anticorps recombinants neutralisant des toxines à partir de primates non humains et localisation de l'épitope d'un anticorps." Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENV044/document.
Повний текст джерелаRecombinant antibodies represent a promising approach to improve the treatment andprophylaxis of diseases caused by bioweapons. Such antibodies may be isolated from nonhumanprimates, whose immunization is much easier to conceive and realized thanimmunization of humans. Chimpanzees (Pan troglodytes) and macaques (Macaca mulattaand M. fascicularis, particularly) have been utilized for such purposes, and our sequenceanalysis has demonstrated that using chimpanzees does not bring a significant advantagedespite their closer phylogenetic proximity with humans. The rest of this thesis has thusutilized macaques, easier to access in France than chimpanzees. In the context of theEuropean AntiBotABE project, phage-displayed immune libraries have been constructed fromimmunized macaques (M. fascicularis) then screened, and scFv simultaneously neutralizingbotulinum toxins (BoNT) A1 and A2 by targeting their heavy chains, and BoNT/E3 bytargeting its light chain were isolated. On the other side, an antibody cross-neutralizing thelethal toxin and the edema toxin of Bacillus anthracis had been formerly isolated. Its epitopeshave been mapped in the course of the present thesis by a method taking advantage of itscross-reactivity. They correspond to the [229-230]-[234-236] region of LF (Lethal Factor)subunit and to the [229-230]-[234-236] region of EF (Edema Factor) subunit. The principle ofthis epitope mapping could be re-employed to map the epitopes of BoNT-neutralizing scFv
Semaan, Bernard. "Raffinement de la localisation d’images provenant de sites participatifs pour la mise à jour de SIG urbain." Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0055/document.
Повний текст джерелаCities are active spots in the earth globe. They are in constant change. New building constructions, demolitions and business changes may apply on daily basis. City managers aim to keep as much as possible an updated digital model of the city. The model may consist of 2D maps but may also be a 3D reconstruction or a street imagery sequence. In order to share the geographical information and keep a 2D map updated, collaborative cartography was born. "OpenStreetMap.org" platform is one of the most known platforms in this field. In order to create an active collaborative database of street imagery we suggest using 2D images available on image sharing platforms like "Flickr", "Twitter", etc. Images downloaded from such platforms feature a rough localization and no orientation information. We propose a system that helps finding a better localization of the images and providing an information about the camera orientation they were shot with. The system uses both visual and semantic information existing in a single image. To do that, we present a fully automatic processing chain composed of three main layers: Data retrieval and preprocessing layer, Features extraction layer, Decision Making layer. We then present the whole system results combining both semantic and visual information processing results. We call our system Data Gathering system for image Pose Estimation (DGPE). We also present a new automatic method for simple architecture building detection we have developed and used in our system. This method is based on segments detected in the image and was called Segments Based Building Detection (SBBD). We test our method against some weather changes and occlusion problems. We finally compare our building detection results with another state-of-the-art method using several images databases
Boscaro, Anthony. "Analyse multimodale et multicritères pour l'expertise et la localisation de défauts dans les composants électriques modernes." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCK014/document.
Повний текст джерелаThe purpose of this manuscript is to exhibit the research work solving the issue of data processing stem from defect localization techniques. This step being decisive in the failure analysis process, scientists have to harness data coming from light emission and laser techniques. Nevertheless, this analysis process is sequential and only depends on the expert’s decision. This factor leads to a not quantified probability of localization. Consequently to solve these issues, a multimodaland multicriteria analysis has been developped, taking advantage of the heterogeneous and complementary nature of light emission and laser probing techniques. This kind of process is based on advanced level tools such as signal/image processing and data fusion. The final aim being to provide a quantitive and qualitative decision help for the experts.The first part of this manuscript is dedicated to the description of the entire process for 1D and 2D data enhancement. Thereafter, the spatio-temporal analysis of laser probing waveforms will be tackled. Finally, the last part highlights the decision support brought by data fusion
Braga, Reinaldo. "LIDU : une approche basée sur la localisation pour l'identification de similarités d'intérêts entre utilisateurs dans les réseaux sociaux." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00771457.
Повний текст джерелаKinnaert, Xavier. "Data processing of induced seismicity : estimation of errors and of their impact on geothermal reservoir models." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAH013/document.
Повний текст джерелаInduced seismicity location and focal mechanisms are commonly used to image the sub-surface designin reservoirs among other tasks. In this Ph.D. the inaccuracies and uncertainties on earthquake location and focal mechanisms are quantified using a three-step method. The technique is applied to the geothermal sites of Soultz and Rittershoffen to investigate the effect of several criteria on thee arthquake location. A good azimuthal seismic coverage and the use of seismic down-hole sensors seriously decrease the location uncertainty. On the contrary, velocity model uncertainties, represented by a 5% Gaussian distribution of the velocity model around the reference model, will multiply location uncertainties by a factor of 2 to 3. An incorrect knowledge of the sub-surface or the simplifications performed before the earthquake location can lead to biases of 10% of the vertical distance separating the source and the stations with a non-isotropic spatial distribution. Hence the sub-surface design maybe distorted in the interpretations. To prevent from that fact, the calibration shot method was proved to be efficient. The study on focal mechanism errors seems to lead to different conclusions. Obviously, the angular bias may be increased by neglecting the fault in the velocity. But, it may also be the same as or even smaller than the bias calculated for the case simulating a perfect knowledge of the medium of propagation. Furthermore a better seismic coverage always leads to smaller angular biases. Hence,it is worth advising to use more than only earthquake location in order to image a reservoir. Other geothermal sites and reservoirs may benefit from the method developed here
Die korrekte Lokalisierung von induzierter Seismizität und den dazugehörigen Herdflächenlösungensind sehr wichtige Parameter. So werden zum Beispiel die Verteilung der Erdbeben und die Orientierung ihrer Herdflächenlösungen dazu benutzt um in der Tiefe liegende Reservoirs zulokalisieren und abzubilden. In dieser Doktorarbeit wird eine Technik vorgeschlagen um diemethodisch bedingten Fehler zu quantifizieren. Mit dieser Methode werden die verschiedenen Fehlerquellen, die Unsicherheiten und die Fehler im Modell getrennt. Die Technik wird für die geothermischen Felder in Soultz und in Rittershoffen benutzt um den Einfluss verschiedener Parameter (Annahmen) auf die Lokalisierung der induzierten Seismizität zu bestimmen. Es wurde festgestellt, dass Bohrlochseismometer und eine gute azimutale Verteilung der seismischen Stationen die Unbestimmtheiten verkleinern. Die Geschwindigkeitsunbestimmheiten, die durch eine Gauss-Verteilung mit 5% Fehler dargestellt werden, vervielfachen die Lokalisierungsungenauigkeiten um einen Faktor 2 bis 3. Eine ungenaue Kenntnis des Untergrunds oder die verwendete vereinfachte Darstellung der Geschwindigkeitsverhältnisse im Untergrund (notwendig um die synthetischen Rechnungen durchführen zu können) führen zu anisotropen Abweichungen und Fehlern in der Herdtiefe von bis zu 10%. Diese können die Interpretationen des Untergrunds deutlich verfälschen. Ein “calibration shot” kann diese Fehler korrigieren. Leider können die Fehler für die Herdflächenlösungen nicht in derselben Weise korrigiert werden. Es erscheint daher als keine gute Idee, ein Reservoir nur über die Lokalisierung von Erdbeben zu bestimmen. Eine Kombination mehrerer seismischer Methoden scheint angezeigt. Die hier besprochene Methode kann als Grundlage dienen für die Erkundung anderer (geothermischer)
Alhmiedat, Tareq Ali. "Tracking mobile targets through Wireless Sensor Networks." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/5524.
Повний текст джерелаToussaint, Renaud. "Fracturation des roches en compression : le processus de localisation en tant que phénomène critique." Phd thesis, Université Rennes 1, 2001. http://tel.archives-ouvertes.fr/tel-00012208.
Повний текст джерелаfortes pressions de confinement présente des traits communs avec une transition de phase thermodynamique: la déformation se localise rapidement à l'échelle des grains dès la sortie du régime élastique réversible, tout en restant d'abord homogène aux grandes échelles. Alors que les microfractures individuelles croissent encore de façon stable, apparaissent autour de la contrainte pic des structures de grande échelle (bandes de cisaillement) qui brisent spontanément les symétries translationnelle et rotationnelle du problème.
Analysant des données déformation/contrainte obtenues sur diverses
roches et conditions de charge, on montre que celles-ci présentent
un haut degré d'universalité, à savoir que la pente de charge est une loi de puissance de l'écart à la contrainte pic, avec un exposant identique dans les différentes experiences à la résolution expérimentale près. Cette loi est vérifiée pratiquement de la sortie du régime élastique, à la contrainte pic.
Le fait que cet exposant semble indépendant de la roche, conjoint aux brisures de symétries et à l'émergence d'une structuration macroscopique, est typique d'un point critique. En conséquence, on développe à partir d'un simple postulat de maximisation d'entropie un formalisme de physique statistique adapté à ce problème. On obtient ainsi une distribution de probabilité sur les configurations de microfractures, en fonction de l'énergie nécessaire à leur formation. partir d'un modèle pour ces énergies basé sur des interactions élastiques, on obtient un système présentant deux transitions de phase: la première correspond à l'initiation de l'activité des microfractures, la seconde à la localisation macroscopique.
Ce modèle prédit à l'approche de la seconde transition le comportement quadratique observé dans les données, alors que le module d'Young effectif du matériau reste fini.
Chemloul, Mohamed. "Etude et réalisation d'un système rapide pour la localisation des rayons X dans les détecteurs gazeux." Université Joseph Fourier (Grenoble), 1995. http://www.theses.fr/1995GRE10014.
Повний текст джерелаBader, Kaci. "Tolérance aux fautes pour la perception multi-capteurs : application à la localisation d'un véhicule intelligent." Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP2161/document.
Повний текст джерелаPerception is a fundamental input for robotic systems, particularly for positioning, navigation and interaction with the environment. But the data perceived by these systems are often complex and subject to significant imprecision. To overcome these problems, the multi-sensor approach uses either multiple sensors of the same type to exploit their redundancy or sensors of different types for exploiting their complementarity to reduce the sensors inaccuracies and uncertainties. The validation of the data fusion approach raises two major problems. First, the behavior of fusion algorithms is difficult to predict, which makes them difficult to verify by formal approaches. In addition, the open environment of robotic systems generates a very large execution context, which makes the tests difficult and costly. The purpose of this work is to propose an alternative to validation by developing fault tolerance mechanisms : since it is difficult to eliminate all the errors of the perceptual system, We will try to limit impact in their operation. We studied the inherently fault tolerance allowed by data fusion by formally analyzing the data fusion algorithms, and we have proposed detection and recovery mechanisms suitable for multi-sensor perception, we implemented the proposed mechanisms on vehicle localization application using Kalman filltering data fusion. We evaluated the proposed mechanims using the real data replay and fault injection technique
Boskovitz, Agnes, and abvi@webone com au. "Data Editing and Logic: The covering set method from the perspective of logic." The Australian National University. Research School of Information Sciences and Engineering, 2008. http://thesis.anu.edu.au./public/adt-ANU20080314.163155.
Повний текст джерелаMichot, Julien. "Recherche linéaire et fusion de données par ajustement de faisceaux : application à la localisation par vision." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2010. http://tel.archives-ouvertes.fr/tel-00626489.
Повний текст джерелаSigwarth, Olivier. "Localisation faible de la lumière par un gaz d'atomes froids en présence d'un champ magnétique." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2004. http://tel.archives-ouvertes.fr/tel-00006473.
Повний текст джерелаd'atomes froids en présence d'un champ magnétique. Plus précisément,
elle est consacrée à l'augmentation cohérente de l'intensité diffuse
dans la direction arrière, due à l'interférence entre chemins de
diffusion multiple rencontrant les mêmes diffuseurs dans l'ordre inverse.
Nous présentons des résultats théoriques rendant compte d'observations
expérimentales récentes sur la forme et l'amplitude du profil d'intensité.
En particulier, nous montrons qu'un champ
magnétique peut en augmenter l'amplitude si les atomes possèdent un niveau
fondamental dégénéré, à l'opposé de ce qui se produit pour des
diffuseurs classiques. Nous discutons l'intérêt de ce résultat en vue
de la localisation forte de la lumière.
Vellettaz, Nicolas. "Optimisation d'un détecteur gazeux à micro-pistes destiné à la localisation à deux dimensions des neutrons thermiques." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10091.
Повний текст джерелаLi, Franck. "Lane-level vehicle localization with integrity monitoring for data aggregation." Thesis, Compiègne, 2018. http://www.theses.fr/2018COMP2458/document.
Повний текст джерелаThe information stored in digital road maps has become very important for intelligent vehicles. As intelligent vehicles address more complex environments, the accuracy requirements for this information have increased. Regarded as a geographic database, digital road maps contain contextual information about the road network, crucial for a good understanding of the environment. When combined with data acquired from on-board sensors, a better representation of the environment can be made, improving the vehicle’s situation understanding. Sensors performance can vary drastically depending on the location of the vehicle, mainly due to environmental factors. Comparatively, a map can provide prior information more reliably but to do so, it depends on another essential component: a localization system. Global Navigation Satellite Systems (GNSS) are commonly used in automotive to provide an absolute positioning of the vehicle, but its accuracy is not perfect: GNSS are prone to errors, also depending greatly on the environment (e.g., multipaths). Perception and localization systems are two important components of an intelligent vehicle whose performances vary in function of the vehicle location. This research focuses on their common denominator, the digital road map, and its use as a tool to assess their performance. The idea developed during this thesis is to use the map as a learning canvas, to store georeferenced information about the performance of the sensors during repetitive travels. This requires a robust localization with respect to the map to be available, through a process of map-matching. The main problematic is the discrepancy between the accuracy of the map and of the GNSS, creating ambiguous situations. This thesis develops a map-matching algorithm designed to cope with these ambiguities by providing multiple hypotheses when necessary. The objective is to ensure the integrity of the result by returning a hypothesis set containing the correct matching with high probability. The method relies on proprioceptive sensors via a dead-reckoning approach aided by the map. A coherence checking procedure using GNSS redundant information is then applied to isolate a single map-matching result that can be used to write learning data with confidence in the map. The possibility to handle the digital map in read/write operation has been assessed and the whole writing procedure has been tested on data recorded by test vehicles on open roads
Rollings, Graham. "Using evolutionary algorithms to resolve 3-dimensional geometries encoded in indeterminate data-sets." Thesis, University of Exeter, 2011. http://hdl.handle.net/10036/4326.
Повний текст джерелаAmadou, Kountché Djibrilla. "Localisation dans les bâtiments des personnes handicapées et classification automatique de données par fourmis artificielles." Thesis, Tours, 2013. http://www.theses.fr/2013TOUR4021/document.
Повний текст джерелаThe concept of « smart » invades more and more our daily life. A typical example is the smartphone, which becames by years an essential device. Soon, it’s the city, the car and the home which will become « smart ». The intelligence is manifested by the ability for the environment to interact and to take decisons in its relationships with users and other environments. This needs information on state changes occurred on both sides. Sensor networks allow to collect these data, to apply on them some pre-processings and to transmit them. Sensor network, towards some of their caracteristics are closed to Swarm Intelligence in the sense that small entities with reduced capababilities can cooperate automatically, in unattended, decentralised and distributed manner in order to accomplish complex tasks. These bio-inspired methods have served as basis for the resolution of many problems, mostly optimization and this insipired us to apply them on problems met in Ambient Assisted Living and on the data clustering problem. AAL is a sub-field of context-aware services, and its goals are to facilitate the everyday life of elderly and disable people. These systems determine the context and then propose different kind of services. We have used two important elements of the context : the position and the disabilty. Although positioning has very good precision outdoor, it faces many challenges in indoor environments due to the electromagnetic wave propagation in harsh conditions, the cost of systems, interoperabilty, etc. Our works have been involved in positioning disabled people in indoor environment by using wireless sensor network for determining the caracteristics of the electromagnetic wave (signal strenght, time, angle) for estimating the position by geometric methods (triangulation, lateration), fingerprinting methods (k-nearest neighbours), baysiens filters (Kalman filter). The application is to offer AAL services like navigation. Therefore we extend the definition of sensor node to take into account any device, in the environment, capable of emiting and receiving a signal. Also, we have studied the possibility of using Pachycondylla Apicalis for data clustering and for indoor localization by casting this last problem as data clustering problem. Finally we have proposed a system based on a middleware architecture
Bachir, Danya. "Estimating urban mobility with mobile network geolocation data mining." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLL004/document.
Повний текст джерелаIn the upcoming decades, traffic and travel times are expected to skyrocket, following tremendous population growth in urban territories. The increasing congestion on transport networks threatens cities efficiency at several levels such as citizens well-being, health, economy, tourism and pollution. Thus, local and national authorities are urged to promote urban planning innovation by adopting supportive policies leading to effective and radical measures. Prior to decision making processes, it is crucial to estimate, analyze and understand daily urban mobility. Traditionally, the information on population movements has been gathered through national and local reports such as census and surveys. Still, such materials are constrained by their important cost, inducing extremely low-update frequency and lack of temporal variability. On the meantime, information and communications technologies are providing an unprecedented quantity of up-to-date mobility data, across all categories of population. In particular, most individuals carry their mobile phone everywhere through their daily trips and activities. In this thesis, we estimate urban mobility by mining mobile network data, which are collected in real-time by mobile phone providers at no extra-cost. Processing the raw data is non-trivial as one must deal with temporal sparsity, coarse spatial precision and complex spatial noise. The thesis addresses two problematics through a weakly supervised learning scheme (i.e., using few labeled data) combining several mobility data sources. First, we estimate population densities and number of visitors over time, at fine spatio-temporal resolutions. Second, we derive Origin-Destination matrices representing total travel flows over time, per transport modes. All estimates are exhaustively validated against external mobility data, with high correlations and small errors. Overall, the proposed models are robust to noise and sparse data yet the performance highly depends on the choice of the spatial resolution. In addition, reaching optimal model performance requires extra-calibration specific to the case study region and to the transportation mode. This step is necessary to account for the bias induced by the joined effect of heterogeneous urban density and user behavior. Our work is the first successful attempt to characterize total road and rail passenger flows over time, at the intra-region level.Although additional in-depth validation is required to strengthen this statement, our findings highlight the huge potential of mobile network data mining for urban planning applications
Li, Hao. "Cooperative perception : Application in the context of outdoor intelligent vehicle systems." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2012. http://pastel.archives-ouvertes.fr/pastel-00766986.
Повний текст джерелаAhriz, Roula Iness. "Application des techniques d'apprentissage à la géolocalisation par radio fingerprint." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2010. http://pastel.archives-ouvertes.fr/pastel-00546952.
Повний текст джерелаNuñez, del Prado Cortez Miguel. "Inference attacks on geolocated data." Thesis, Toulouse, INSA, 2013. http://www.theses.fr/2013ISAT0028/document.
Повний текст джерелаIn recent years, we have observed the development of connected and nomad devices suchas smartphones, tablets or even laptops allowing individuals to use location-based services(LBSs), which personalize the service they offer according to the positions of users, on a dailybasis. Nonetheless, LBSs raise serious privacy issues, which are often not perceived by the endusers. In this thesis, we are interested in the understanding of the privacy risks related to thedissemination and collection of location data. To address this issue, we developed inferenceattacks such as the extraction of points of interest (POI) and their semantics, the predictionof the next location as well as the de-anonymization of mobility traces, based on a mobilitymodel that we have coined as mobility Markov chain. Afterwards, we proposed a classificationof inference attacks in the context of location data based on the objectives of the adversary.In addition, we evaluated the effectiveness of some sanitization measures in limiting the efficiencyof inference attacks. Finally, we have developed a generic platform called GEPETO (forGEoPrivacy Enhancing Toolkit) that can be used to test the developed inference attacks
Féraud, Thomas. "Rejeu de chemin et localisation monoculaire : application du Visual SLAM sur carte peu dense en environnement extérieur contraint." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00697028.
Повний текст джерелаIrain, Malik. "Plateforme d'analyse de performances des méthodes de localisation des données dans le cloud basées sur l'apprentissage automatique exploitant des délais de messages." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30195.
Повний текст джерелаCloud usage is a necessity today, as data produced and used by all types of users (individuals, companies, administrative structures) has become too large to be stored otherwise. It requires to sign, explicitly or not, a contract with a cloud storage provider. This contract specifies the levels of quality of service required for various criteria. Among these criteria is the location of the data. However, this criterion is not easily verifiable by a user. This is why research in the field of data localization verification has led to several studies in recent years, but the proposed solutions can still be improved. The work proposed in this thesis consists in studying solutions of location verification by a user, i.e. solutions that estimate data location and operate using landmarks. The implemented approach can be summarized as follows: exploiting communication delays and using network time models to estimate, with some distance error, data location. To this end, the work carried out is as follows: • A survey of the state of the art on the different methods used to provide users with location information. • The design of a unified notation for the methods studied in the survey, with a proposal of two scores to assess methods. • Implementation of a network measurements collecting platform. Thanks to this platform, two datasets were collected, at both national level and international level. These two data sets are used to evaluate the different methods presented in the state of the art survey. • Implementation of an evaluation architecture based on the two data sets and the defined scores. This allows us to establish the quality of the methods (success rate) and the quality of the results (accuracy of the result) thanks to the proposed scores
Hofleitner, Aude. "Développement d'un modèle d'estimation des variables de trafic urbain basé sur l'utilisation des technologies de géolocalisation." Phd thesis, Université Paris-Est, 2012. http://tel.archives-ouvertes.fr/tel-00798239.
Повний текст джерела