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Thèses sur le sujet « D Estimation »

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Publié le 10 mars 2023

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1

Tewfik, Ahmed H. « Recursive estimation and spectral estimation for 2-D isotropic random fields ». Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14928.

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Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1987.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaves 180-188.
by Ahmed Hossam Tewfik.
Sc.D.

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2

Kacete, Amine. « Unconstrained Gaze Estimation Using RGB-D Camera ». Thesis, CentraleSupélec, 2016. http://www.theses.fr/2016SUPL0012/document.

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Dans ce travail, nous avons abordé le problème d’estimation automatique du regard dans des environnements utilisateur sans contraintes. Ce travail s’inscrit dans la vision par ordinateur appliquée à l’analyse automatique du comportement humain. Plusieurs solutions industrielles sont aujourd’hui commercialisées et donnent des estimations précises du regard. Certaines ont des spécifications matérielles très complexes (des caméras embarquées sur un casque ou sur des lunettes qui filment le mouvement des yeux) et présentent un niveau d’intrusivité important, ces solutions sont souvent non accessible au grand public. Cette thèse vise à produire un système d’estimation automatique du regard capable d’augmenter la liberté du mouvement de l’utilisateur par rapport à la caméra (mouvement de la tête, distance utilisateur-capteur), et de réduire la complexité du système en utilisant des capteurs relativement simples et accessibles au grand public. Dans ce travail, nous avons exploré plusieurs paradigmes utilisés par les systèmes d’estimation automatique du regard. Dans un premier temps, Nous avons mis au point deux systèmes basés sur deux approches classiques: le premier basé caractéristiques et le deuxième basé semi apparence. L’inconvénient majeur de ces paradigmes réside dans la conception des systèmes d'estimation du regard qui supposent une indépendance totale entre l'image d'apparence des yeux et la pose de la tête. Pour corriger cette limitation, Nous avons convergé vers un nouveau paradigme qui unifie les deux blocs précédents en construisant un espace regard global, nous avons exploré deux directions en utilisant des données réelles et synthétiques respectivement
In this thesis, we tackled the automatic gaze estimation problem in unconstrained user environments. This work takes place in the computer vision research field applied to the perception of humans and their behaviors. Many existing industrial solutions are commercialized and provide an acceptable accuracy in gaze estimation. These solutions often use a complex hardware such as range of infrared cameras (embedded on a head mounted or in a remote system) making them intrusive, very constrained by the user's environment and inappropriate for a large scale public use. We focus on estimating gaze using cheap low-resolution and non-intrusive devices like the Kinect sensor. We develop new methods to address some challenging conditions such as head pose changes, illumination conditions and user-sensor large distance. In this work we investigated different gaze estimation paradigms. We first developed two automatic gaze estimation systems following two classical approaches: feature and semi appearance-based approaches. The major limitation of such paradigms lies in their way of designing gaze systems which assume a total independence between eye appearance and head pose blocks. To overcome this limitation, we converged to a novel paradigm which aims at unifying the two previous components and building a global gaze manifold, we explored two global approaches across the experiments by using synthetic and real RGB-D gaze samples

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Müller, Werner, et Dale L. Zimmerman. « Optimal Design for Variogram Estimation ». Department of Statistics and Mathematics, WU Vienna University of Economics and Business, 1997. http://epub.wu.ac.at/756/1/document.pdf.

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The variogram plays a central role in the analysis of geostatistical data. A valid variogram model is selected and the parameters of that model are estimated before kriging (spatial prediction) is performed. These inference procedures are generally based upon examination of the empirical variogram, which consists of average squared differences of data taken at sites lagged the same distance apart in the same direction. The ability of the analyst to estimate variogram parameters efficiently is affected significantly by the sampling design, i.e., the spatial configuration of sites where measurements are taken. In this paper, we propose design criteria that, in contrast to some previously proposed criteria oriented towards kriging with a known variogram, emphasize the accurate estimation of the variogram. These criteria are modifications of design criteria that are popular in the context of (nonlinear) regression models. The two main distinguishing features of the present context are that the addition of a single site to the design produces as many new lags as there are existing sites and hence also produces that many new squared differences from which the variograrn is estimated. Secondly, those squared differences are generally correlated, which inhibits the use of many standard design methods that rest upon the assumption of uncorrelated errors. Several approaches to design construction which account for these features are described and illustrated with two examples. We compare their efficiency to simple random sampling and regular and space-filling designs and find considerable improvements. (author's abstract)
Series: Forschungsberichte / Institut für Statistik

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Vanhems, Anne. « Estimation non paramétrique de solutions d' équations différentielles ». Toulouse 1, 2001. http://www.theses.fr/2001TOU10102.

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Notre travail a pour objet l' étude statistique de paramètres fonctionnels définis comme solutions d' équations différentielles dépendant de la loi de probabilité des données. De tels problèmes se posent fréquemment en économie, physique, finance où les modèles définissent les paramètres d' intérêt comme solutions d' équations différentielles
The objective of our work is to make statistical inference on functional parameters which are solutions of differential equations depending on the data distribution. Such problems are often encountered in economics, physics, finance, where the interest parameters are solutions of differential equations

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Oyini, Mbouna Ralph. « 3-D Face Modeling from a 2-D Image with Shape and Head Pose Estimation ». Diss., Temple University Libraries, 2014. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/305734.

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Electrical and Computer Engineering
Ph.D.
This paper presents 3-D face modeling with head pose and depth information estimated from a 2-D query face image. Many recent approaches to 3-D face modeling are based on a 3-D morphable model that separately encodes the shape and texture in a parameterized model. The model parameters are often obtained by applying statistical analysis to a set of scanned 3-D faces. Such approaches tend to depend on the number and quality of scanned 3-D faces, which are difficult to obtain and computationally intensive. To overcome the limitations of 3-D morphable models, several modeling techniques from 2-D images have been proposed. We propose a novel framework for depth estimation from a single 2-D image with an arbitrary pose. The proposed scheme uses a set of facial features in a query face image and a reference 3-D face model to estimate the head pose angles of the face. The depth information of the subject at each feature point is represented by the depth information of the reference 3-D face model multiplied by a vector of scale factors. We use the positions of a set of facial feature points on the query 2-D image to deform the reference face dense model into a person specific 3-D face by minimizing an objective function. The objective function is defined as the feature disparity between the facial features in the face image and the corresponding 3-D facial features on the rotated reference model projected onto 2-D space. The pose and depth parameters are iteratively refined until stopping criteria are reached. The proposed method requires only a face image of arbitrary pose for the reconstruction of the corresponding 3-D face dense model with texture. Experiment results with USF Human-ID and Pointing'04 databases show that the proposed approach is effective to estimate depth and head pose information with a single 2-D image.
Temple University--Theses

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Rose, Christopher James. « An adaptive D-STATCOM control scheme utilising impedance estimation ». Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32915/.

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Concerns for energy security and the environment are driving significant changes in the way electrical power is generated and distributed. In many parts of the world, electrical power systems are gradually changing from centralised systems with a small number of large generators and substations performing most control operations to distributed systems, with a large number of devices providing control at a local level. Power electronic converters have an increasingly important role to play in modern electrical power systems. One example of power electronics in such systems is the STATCOM, a power electronic device which can be used to provide an efficient and effective means of controlling power system voltages. This thesis presents an investigation into STATCOM voltage control for distribution level power networks. In this work, a STATCOM voltage control structure is proposed and an impedance estimation algorithm is used to tune the controller gains in order to achieve the desired dynamic performance. This work demonstrates that the use of impedance estimation for controller tuning allows the STATCOM dynamics to remain consistent when installed on different systems or if the system impedance should change. In addition to proposing the voltage control structure, this thesis also proposes improvements to an earlier impedance estimation method, taking into account changes in converter structures and control methods since the method was first proposed.

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Azarbayejani, Ali J. « Nonlinear probabilistic estimation of 3-D geometry from images ». Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/29122.

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Yu, Xiaoju, et Hao Xin. « 3-D Direction of Arrival Estimation with Two Antennas ». International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595622.

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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada
Inspired by human auditory system, an improved direction of arrival (DOA) technique using only two antennas with a scatterer in between them to achieve additional magnitude cues is proposed. By exploiting the incident-angle-dependent magnitude and phase differences between the two monopole antennas and applying 2-D / 3-D multiple signal classification algorithms (MUSIC), the DOA of an incident microwave signal can be estimated. Genetic algorithm is applied to optimize the scatterer geometry for the 3-D DOA estimation. The simulated results of both the azimuth and three-dimensional DOA estimation have shown an encouraging accuracy and sensitivity by incorporating a lossy scatterer.

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Marti, Lucas. « Estimation de la posture humaine par capteur RGB-D ». Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30394.

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Dans le contexte du vieillissement de la population, le problème de la chute est un problème de santé publique. L'utilisation de la technologie est un axe important pour la prise en compte des enjeux liés à la chute. Nous voulons développer un système complet de détection et d'estimation de la chute à destination des maison de retraites et des particuliers dans un but d'amélioration de la prise en charge médicale et de limitation des conséquences de la chute. La solution de détection à l'aide d'un capteur ambiant déporté nous a semblé être la solution la plus adaptée. Les capteurs RGB-D (couleurs + profondeur) développés récemment sont un atout pour cela car ils sont peu chers, très commun et performants.La première partie de la thèse traite du problème de segmentation de la silhouette de la personne dans la scène observée. Nous présentons un algorithme qui fourni, grâce à une utilisation conjointe des images de couleurs et de profondeur, les silhouettes des différents personnes dans la pièce dans laquelle est situé le capteur. L'algorithme est robuste au changement de configuration de la pièce et notamment au déplacement d'objets. L'utilisation de caractéristiques propres à la profondeur nous permet d'atteindre des niveaux de performances suffisant pour une utilisation industrielle. Dans la seconde partie de la thèse nous abordons le problème de l'estimation de la posture humaine. Une fois les silhouettes segmentées grâce à l'algorithme de la première partie, nous voulons avoir les positions des articulations de la personne. Nous incrémentons sur les algorithmes déjà existants utilisant l'apprentissage et notamment les algorithmes des randoms forests en investiguant de nouvelles idées pour augmenter les performances. Nous déterminons les valeurs optimales de certains paramètres qui ne sont pas explorés dans les travaux précedents. Nous présentons un nouveau type de caractéristique à calculer sur les images de profondeur. Nous examinons enfin l'impact de l'équilibrage de la collection d'apprentissage dans notre contexte. L'algorithme fourni alors un ensemble de prédiction pour chaque articulation.Dans la troisième partie, nous traitons le problème du filtrage spatio-temporel des poses. Nous présentons différentes approches et nous intéressons à l'ambiguïté droite/gauche des membres et cherchons à traiter ce problème. Les approches utilisées se fonde sur le filtrage bayesien
In a world with an increasingly aging population, elderly people falling are a public health issue. The use of technology is a major development axis for fall management. We want to design a complete system for detection and estimation of falls. The target market for this system is medicalized retirement homes and individual homes. We want to improve the medical care of people after the fall in order to lower its consequences. A solution based on an ambient sensor seems to be the most adapted solution. Recent development in RGB-D (Color+Depth) sensing are a great asset thanks to their relatively low cost, wide availability and good performances. The first part of the thesis deals with the problem of segmenting people for the surrounding scene in our images. We present an algorithm that gives, thanks to use simultaneous use of color and depth, the silhouettes of each person in the room in which the sensor is installed. The algorithm is robust to the change of configuration of the room and especially to moving furniture. We use special consideration of depth to reach a performance level sufficient for an industrial application. The second part of the thesis deals with the estimation of the human posture. Once the silhouettes have been segmented with the algorithm of the first part, we want to get an estimation of every articulation of the person. We build on existing algorithms that use machine learning and in particular Random Forest by investigating new ideas to improve performances. We found optimal values for some parameters that were not previously investigated. We present a new feature to be computed on depth images. Finally we evaluate the impact of balancing the training database in our context. The algorithm provides a set of predictions for the position of every articulation. In the third part, we are interested in spatio-temporal filtering of the postures. We present different approaches and in particular we deal with the issue of left/right ambiguity that arises in the algorithm of the previous part. The approaches are based on Bayesian filtering

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Kaval, Huseyin. « 2-d Mesh-based Motion Estimation And Video Object Manipulation ». Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608869/index.pdf.

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Motion estimation and compensation plays an important role in video processing applications. Two-dimensional block-based and mesh-based models are widely used in this area. A 2-D mesh-based model provides a better representation of complex real world motion than a block-based model. Mesh-based motion estimation algorithms are employed in both frame-based and object-based video compression and coding. A hierarchical mesh-based algorithm is applied to improve the motion field generated by a single-layer algorithm. 2-D mesh-based models also enable the manipulation of video objects which is included in the MPEG-4 standard. A video object in a video clip can be replaced by another object by the use of a dynamic mesh structure. In this thesis, a comparative analysis of 2-D block-based and mesh-based motion estimation algorithms in both frame-based and object-based video representations is performed. The experimental results indicate that a mesh-based algorithm produces better motion compensation results than a block-based algorithm. Moreover, a two-layer mesh-based algorithm shows improvement over a one-layer mesh-based algorithm. The application of mesh-based motion estimation and compensation to video object replacement and animation is also performed.

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Mukherjee, Nandini. « 3-D deormable contour surface reconstruction an optimized estimation method / ». Cincinnati, Ohio : University of Cincinnati, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=ucin1078255615.

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12

Reinert, Regina Miriam [Verfasser]. « Unbounded number line estimation : A purer measure of numerical estimation ? / Regina Miriam Reinert ». Tübingen : Universitätsbibliothek Tübingen, 2021. http://d-nb.info/1227924488/34.

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Reinert, Regina M. [Verfasser]. « Unbounded number line estimation : A purer measure of numerical estimation ? / Regina Miriam Reinert ». Tübingen : Universitätsbibliothek Tübingen, 2021. http://d-nb.info/1227924488/34.

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Demetz, Oliver [Verfasser], et Joachim [Akademischer Betreuer] Weickert. « Feature invariance versus change estimation in variational motion estimation / Oliver Demetz. Betreuer : Joachim Weickert ». Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2015. http://d-nb.info/1077211600/34.

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Rosenhahn, Bodo [Verfasser]. « Pose Estimation Revisited / Bodo Rosenhahn ». Kiel : Universitätsbibliothek Kiel, 2003. http://d-nb.info/1080332448/34.

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Chi, Hongbo. « An Improved Framework for Dynamic Origin-Destination (O-D) Matrix Estimation ». FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/289.

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This dissertation aims to improve the performance of existing assignment-based dynamic origin-destination (O-D) matrix estimation models to successfully apply Intelligent Transportation Systems (ITS) strategies for the purposes of traffic congestion relief and dynamic traffic assignment (DTA) in transportation network modeling. The methodology framework has two advantages over the existing assignment-based dynamic O-D matrix estimation models. First, it combines an initial O-D estimation model into the estimation process to provide a high confidence level of initial input for the dynamic O-D estimation model, which has the potential to improve the final estimation results and reduce the associated computation time. Second, the proposed methodology framework can automatically convert traffic volume deviation to traffic density deviation in the objective function under congested traffic conditions. Traffic density is a better indicator for traffic demand than traffic volume under congested traffic condition, thus the conversion can contribute to improving the estimation performance. The proposed method indicates a better performance than a typical assignment-based estimation model (Zhou et al., 2003) in several case studies. In the case study for I-95 in Miami-Dade County, Florida, the proposed method produces a good result in seven iterations, with a root mean square percentage error (RMSPE) of 0.010 for traffic volume and a RMSPE of 0.283 for speed. In contrast, Zhou’s model requires 50 iterations to obtain a RMSPE of 0.023 for volume and a RMSPE of 0.285 for speed. In the case study for Jacksonville, Florida, the proposed method reaches a convergent solution in 16 iterations with a RMSPE of 0.045 for volume and a RMSPE of 0.110 for speed, while Zhou’s model needs 10 iterations to obtain the best solution, with a RMSPE of 0.168 for volume and a RMSPE of 0.179 for speed. The successful application of the proposed methodology framework to real road networks demonstrates its ability to provide results both with satisfactory accuracy and within a reasonable time, thus establishing its potential usefulness to support dynamic traffic assignment modeling, ITS systems, and other strategies.

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Howell, Randy Keith. « d-MUSIC : an algorithm for single snapshot direction-of-arrival estimation ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ37346.pdf.

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Elbornsson, Jonas. « Analysis, estimation and compensation of mismatch effects in A/D converters / ». Linköping : Univ, 2003. http://www.bibl.liu.se/liupubl/disp/disp2003/tek811s.pdf.

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Burzlaff, Marcus. « Aircraft Fuel Consumption - Estimation and Visualization ». Aircraft Design and Systems Group (AERO), Department of Automotive and Aeronautical Engineering, Hamburg University of Applied Sciences, 2017. http://d-nb.info/1148997490.

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In order to uncover the best kept secret in today's commercial aviation, this project deals with the calculation of fuel consumption of aircraft. With only the reference of the aircraft manufacturer's information, given within the airport planning documents, a method is established that allows computing values for the fuel consumption of every aircraft in question. The aircraft's fuel consumption per passenger and 100 flown kilometers decreases rapidly with range, until a near constant level is reached around the aircraft's average range. At longer range, where payload reduction becomes necessary, fuel consumption increases significantly. Numerical results are visualized, explained, and discussed. With regard to today's increasing number of long-haul flights, the results are investigated in terms of efficiency and viability. The environmental impact of burning fuel is not considered in this report. The presented method allows calculating aircraft type specific fuel consumption based on publicly available information. In this way, the fuel consumption of every aircraft can be investigated and can be discussed openly.

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Maurin, Véronique. « Tentative de mise au point d' une batterie d' estimation des états déficitaires (B. E. D) chez trente sujets âgés ». Clermont-Ferrand 1, 1987. http://www.theses.fr/1987CLF13034.

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L' estimation d' un état déficitaire du sujet âgé est faite à l' aide de tests psychométriques. L' objet du travail est de présenter un test composé d' une part d' épreuves et de l' autre d' échelles comportementales : la batterie d' estimation des démences du Professeur SIGNORET. Comme gage de fiabilité, on a choisi la traduction française de l' échelle de Blessed, seul test reconnu comme ayant une bonne corrélation anatomo-clinique. Trente sujets de plus de soixante ans aphasiques, ayant un état mental permettant de participer aux tests, ont répondu au cours de deux entretiens à la Batterie d' estimation des démences puis à l' échelle de Blessed. L' analyse des résultats reportés sur des histogrammes, retrouve une bonne comparaison des résultats obtenus à chacun des deux tests. Cette batterie n' est pas la batterie définitive, et a subi des modifications de cotation essentiellement. La batterie d' estimation des démences actuelle est présentée en fin de travail : ce test ne nécessite pas de formation de psychométricien et s' adresse au clinicien.

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Wagh, Ameya Yatindra. « A Deep 3D Object Pose Estimation Framework for Robots with RGB-D Sensors ». Digital WPI, 2019. https://digitalcommons.wpi.edu/etd-theses/1287.

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The task of object detection and pose estimation has widely been done using template matching techniques. However, these algorithms are sensitive to outliers and occlusions, and have high latency due to their iterative nature. Recent research in computer vision and deep learning has shown great improvements in the robustness of these algorithms. However, one of the major drawbacks of these algorithms is that they are specific to the objects. Moreover, the estimation of pose depends significantly on their RGB image features. As these algorithms are trained on meticulously labeled large datasets for object's ground truth pose, it is difficult to re-train these for real-world applications. To overcome this problem, we propose a two-stage pipeline of convolutional neural networks which uses RGB images to localize objects in 2D space and depth images to estimate a 6DoF pose. Thus the pose estimation network learns only the geometric features of the object and is not biased by its color features. We evaluate the performance of this framework on LINEMOD dataset, which is widely used to benchmark object pose estimation frameworks. We found the results to be comparable with the state of the art algorithms using RGB-D images. Secondly, to show the transferability of the proposed pipeline, we implement this on ATLAS robot for a pick and place experiment. As the distribution of images in LINEMOD dataset and the images captured by the MultiSense sensor on ATLAS are different, we generate a synthetic dataset out of very few real-world images captured from the MultiSense sensor. We use this dataset to train just the object detection networks used in the ATLAS Robot experiment.

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Smith, Taryn J. « Vitamin D and adolescents : estimation of evidence-based dietary requirements and health outcomes related to vitamin D status ». Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/841753/.

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Vitamin D deficiency and inadequacy are worldwide public health concerns and occur across all age, sex and ethnic groups, with significant implications for human health. Adolescents are a population group at high risk of low vitamin D status, yet the evidence base for establishing vitamin D requirements remains weak. The primary aim of this Thesis was to estimate the dietary vitamin D intakes required to maintain serum 25-hydroxyvitamin D [25(OH)D] concentrations above specific cut-off thresholds (25, 30, 40 and 50 nmol/l) during the winter-time in white Caucasian adolescents residing in the UK (51°N). Secondary aims were to: 1) investigate vitamin D status in relation to musculoskeletal and cardiometabolic health outcomes and; 2) explore familial associations in vitamin D status, dietary intakes and musculoskeletal health in mother-child pairs. This was achieved via a dose-response trial in 110 adolescents (14-18 years), who were randomly allocated to receive 0 (placebo), 10 or 20 μg vitamin D3 daily for 20 weeks during the winter-time. A final aim of this Thesis was to assess the vitamin D status and prevalence of vitamin D deficiency in a small study of African Caribbean and South Asian adolescent and young adult females (16-25 years) in comparison to their white Caucasian counterparts. It was estimated that vitamin D intakes of 10.1, 13.1, 23.3 and ~30 μg/day would maintain serum 25(OH)D concentrations > 25, 30, 40 and 50 nmol/l respectively in 97.5% of the adolescents. Adolescents with serum 25(OH)D concentrations below 50 nmol/l had significantly lower radial trabecular volumetric bone mineral density and presented with a poorer cardiometabolic profile, with greater waist circumference and higher triglyceride and glucose concentrations than their more replete counterparts. However cardiometabolic risk was lost after controlling for potential confounders. Positive, sex-specific associations were found for serum 25(OH)D concentrations and radial mass, total area and cortical volumetric bone mineral density in mother-child pairs, but not for dietary vitamin D and calcium intakes. A high prevalence of vitamin D deficiency was found in African Caribbean and South Asian females (serum 25(OH)D < 30 nmol/l: 75% and 63% respectively) and serum 25(OH)D concentrations in these ethnic minority populations was half that of their white Caucasian counterparts (22.7 [14.5, 34.0], 22.8 [19.2, 37.1] and 44.4 [36.6, 60.3] nmol/l respectively). In conclusion, dietary vitamin D intakes of between 10 and ~30 μg/day are required by adolescents during the winter-time to maintain serum 25(OH)D concentrations > 25-50 nmol/l, depending on the cut-off threshold selected. These data will allow for future refinement of evidence-based dietary requirements for adolescents. Further studies are now urgently needed to investigate the vitamin D requirements of ethnic minority populations via targeted dose-response vitamin D trials. Finally, the beneficial effects of maintaining serum 25(OH)D concentrations above 50 nmol/l on musculoskeletal health parameters requires confirmation in further randomised trials.

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Ren, Shanshan. « d-Limonene, a Renewable Component for Polymer Synthesis ». Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35849.

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d-Limonene (Lim) was used in various polymer formulations to achieve a more sustainable polymerization. Lim is a renewable and essentially non-toxic compound, derived from citrus fruit peels, that may replace some of the many toxic and fossil-based chemicals used in polymer synthesis. Bulk free-radical polymerizations of n-butyl acrylate (BA) with Lim were performed to investigate Lim co-polymerization kinetics and estimate the monomer reactivity ratios, important parameters in the prediction of copolymer composition. Kinetic modeling of the BA/Lim copolymerization was performed with PREDICI simulation software. The model supports the presence of a significant degradative chain transfer reaction due to Lim. This reaction mechanism is due to the presence of allylic hydrogen in Lim. Nonetheless, relatively high molecular weight polymers were produced. It was concluded that Lim behaves more like a chain transfer agent than a co-monomer. Terpolymerizations of BA, butyl methacrylate (BMA) with Lim were then performed. In order to predict the terpolymer composition, the monomer reactivity ratios for BA/BMA were estimated. By applying the three pairs of co-monomer reactivity ratios to the integrated Mayo-Lewis equation, terpolymer compositions were ably predicted up to high monomer conversion levels. Lim was then used as a chain transfer agent to prepare core-shell latex-based pressure sensitive adhesives (PSA) comprising BA and styrene via seeded semi-batch emulsion polymerization. By varying the concentration of Lim and divinylbenzene crosslinker, the core polymer microstructure was modified to yield different molecular weights and degrees of crosslinking. The core latex was then used as a seed to prepare core-shell latexes. By changing the Lim concentration during the shell-stage polymerization, the molecular weight of shell polymer was also modified. The latexes were characterized for their microstructure and were cast as films for PSA performance evaluation. The PSA performance was shown to be highly related to the polymer microstructure. Tack and peel strength showed a decrease with increasing Lim concentration. Shear strength went through a maximum with a core Lim concentration increase from 0 to 5 phm.

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Lerche, Veronika [Verfasser], et Andreas [Akademischer Betreuer] Voß. « Parameter Estimation in Diffusion Modeling : Guidelines on Requisite Trial Numbers and Estimation Procedures / Veronika Lerche ; Betreuer : Andreas Voß ». Heidelberg : Universitätsbibliothek Heidelberg, 2016. http://d-nb.info/1180737725/34.

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Uhlich, Stefan [Verfasser]. « Parameter Estimation with Additional Information / Stefan Uhlich ». München : Verlag Dr. Hut, 2012. http://d-nb.info/1028783981/34.

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Rosas-Romero, Roberto. « Tracking of 3-D objects with non-rigid deformation estimation in medical images / ». Thesis, Connect to this title online ; UW restricted, 1999. http://hdl.handle.net/1773/6076.

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Sinn, Mathieu. « Estimation of ordinal pattern probabilities in stochastic processes ». Lübeck Zentrale Hochschulbibliothek Lübeck, 2010. http://d-nb.info/1002256178/34.

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Richter, Andreas [Verfasser]. « Estimation of radio channel parameters / von Andreas Richter ». Ilmenau : ISLE, 2005. http://d-nb.info/981051421/34.

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Zablotskaya, Ksenia [Verfasser]. « Automatic estimation of users' verbal intelligence / Ksenia Zablotskaya ». Ulm : Universität Ulm, 2016. http://d-nb.info/1108434827/34.

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Bartke, Philipp [Verfasser]. « Demand Estimation in Airline Revenue Management / Philipp Bartke ». Berlin : Freie Universität Berlin, 2014. http://d-nb.info/1048558584/34.

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Diether, Michael [Verfasser]. « Wavelet estimation in diffusions with periodicity / Michael Diether ». Mainz : Universitätsbibliothek Mainz, 2012. http://d-nb.info/1022300369/34.

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Strübbe, Simon [Verfasser]. « Insect-Inspired Visual Self-Motion Estimation / Simon Strübbe ». Bielefeld : Universitätsbibliothek Bielefeld, 2019. http://d-nb.info/1184476365/34.

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Wissel, Daniel [Verfasser]. « Intrinsic Dimension Estimation using Simplex Volumes / Daniel Wissel ». Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1153467011/34.

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Stefer, Markus [Verfasser]. « DoA Estimation With Reduced Hardware Complexity / Markus Stefer ». München : Verlag Dr. Hut, 2016. http://d-nb.info/1100969071/34.

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Jildeh, Hanin [Verfasser]. « Liquid-Liquid Extraction Columns : Parameter Estimation / Hanin Jildeh ». München : Verlag Dr. Hut, 2015. http://d-nb.info/107976903X/34.

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Çiçek, Özgün [Verfasser], et Thomas [Akademischer Betreuer] Brox. « Uncertainty estimation and its applications in computer vision ». Freiburg : Universität, 2021. http://d-nb.info/1232644889/34.

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Ireta, Munoz Fernando Israel. « Estimation de pose globale et suivi pour la localisation RGB-D et cartographie 3D ». Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4054/document.

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Ce rapport de thèse présente une analyse détaillée de nouvelles techniques d'estimation de pose à partir des images de couleur et de profondeur provenant de capteurs RGB-D. Etant donné que l'estimation de la pose nécessite d'établir une cartographie en simultanée, la reconstruction 3D de la scène sera aussi étudié dans cette thèse. La localisation et la cartographie ont été largement étudiés par la communauté de robotique et de vision par ordinateur, et ces techniques ont aussi été largement employés pour la robotique mobile et les systèmes autonomes afin d'exécuter des tâches telles que le suivi de caméra, la reconstruction 3D dense ou encore la localisation robuste. Le défi de l'estimation de pose réside dans la façon de relier les mesures des capteurs pour estimer l'état système en position et en orientation. Lorsqu'une multitude de capteurs fournisse différentes observations des mêmes variables, il devient alors complexe de fusionner au mieux ces informations acquises à des instants différents. De manière à développer un algorithme efficace pour traiter ces problèmes, une nouvelle méthode de recalage nommée Point-to-hyperplane sera introduite, analysée, comparée et appliquée à l'estimation de pose et à la cartographie basée sur des frames-clés. La méthode proposée permet de minimiser différentes métriques sous la forme d'un seul vecteur de mesure en n-dimensions, sans avoir besoin de définir un facteur d'échelle qui pondère l'influence de chaque terme durant la minimisation d'énergie. Au sein du concept Point-to-hyperplane, deux lignes principales ont été examinées. Premièrement, la méthode proposée sera employée dans des applications d'odométrie visuelle et de cartographie 3D. Compte-tenu des résultats expérimentaux, il a été montré que la méthode proposée permet d'estimer la pose localement avec précision en augmentant le domaine et la vitesse de convergence. L'invariance est mathématiquement prouvée et des résultats sont fournis à la fois pour environnements réels et synthétiques. Deuxièmement, une méthode pour la localisation globale a été proposée qui adresse les problèmes de reconnaissance et de détection de lieux. Cette méthode s'appuie sur l'utilisation du Point-to-hyperplane combinée à une optimisation Branch-and-bound pour estimer la pose globalement. Étant donné que les stratégies de Branch-and-Bound permettent d'obtenir des alignements grossiers sans la nécessité d'avoir la pose initiale entre les images, le Point-tohyperplane peut être utiliser pour raffiner l'estimation. Il sera démontré que cette stratégie est mieux contrainte quand davantage de dimensions sont utilisées. Cette stratégie s'avère être utile pour résoudre les problèmes de désalignement et pour obtenir des cartes 3D globalement consistantes. Pour finir cette thèse et pour démontrer la performance des méthodes proposées, des résultats sur des applications de SLAM visuel et de cartographie 3D sont présentés
This thesis presents a detailed account of novel techniques for pose estimation by using both, color and depth information from RGB-D sensors. Since pose estimation simultaneously requires an environment map, 3D scene reconstruction will also be considered in this thesis. Localization and mapping has been extensively studied by the robotics and computer vision communities and it is widely employed in mobile robotics and autonomous systems for performing tasks such as tracking, dense 3D mapping and robust localization. The central challenge of pose estimation lies in how to relate sensor measurements to the state of position and orientation. When a variety of sensors, which provide different information about the same data points, are available, the challenge then becomes part of how to best fuse acquired information at different times. In order to develop an effective algorithm to deal with these problems, a novel registration method named Point-to-hyperplane Iterative Closest Point will be introduced, analysed, compared and applied to pose estimation and key-frame mapping. The proposed method allows to jointly minimize different metric errors as a single measurement vector with n-dimensions without requiring a scaling factor to tune their importance during the minimization process. Within the Point-to-hyperplane framework two main axes have been investigated. Firstly, the proposed method will be employed for performing visual odometry and 3D mapping. Based on actual experiments, it has been shown that the proposed method allows to accurately estimate the pose locally by increasing the domain of convergence and by speeding up the alignment. The invariance is mathematically proven and results in both, simulated and real environments, are provided. Secondly, a method is proposed for global localization for enabling place recognition and detection. This method involves using the point-to-hyperplane methods within a Branch-and-bound architecture to estimate the pose globally. Therefore, the proposed method has been combined with the Branch-and-bound algorithm to estimate the pose globally. Since Branch-and-bound strategies obtain rough alignments regardless of the initial position between frames, the Point-to-hyperplane can be used for refinement. It will be demonstrated that the bounds are better constrained when more dimensions are considered. This last approach is shown to be useful for solving mistracking problems and for obtaining globally consistent 3D maps. In a last part of the thesis and in order to demonstrate the proposed approaches and their performance, both visual SLAM and 3D mapping results are provided

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Lima, João Paulo Silva do Monte. « Object detection and pose estimation from rectification of natural features using consumer RGB-D sensors ». Universidade Federal de Pernambuco, 2014. https://repositorio.ufpe.br/handle/123456789/12143.

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Submitted by Nayara Passos (nayara.passos@ufpe.br) on 2015-03-12T13:53:20Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE João Paulo Silva do Monte Lima.pdf: 5689244 bytes, checksum: e6e2c3f1da85d18b6bb7049e458f50e7 (MD5)
Made available in DSpace on 2015-03-12T13:53:20Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE João Paulo Silva do Monte Lima.pdf: 5689244 bytes, checksum: e6e2c3f1da85d18b6bb7049e458f50e7 (MD5) Previous issue date: 2014
CAPES , CNPq
Sistemas de Realidade Aumentada são capazes de realizar registro 3D em tempo real de objetos virtuais e reais, o que consiste em posicionar corretamente os objetos virtuais em relação aos reais de forma que os elementos virtuais pareçam ser reais. Uma maneira bastante popular de realizar esse registro é usando detecção e rastreamento de objetos baseado em vídeo a partir de marcadores fiduciais planares. Outra maneira de sensoriar o mundo real usando vídeo é utilizando características naturais do ambiente, o que é mais complexo que usar marcadores planares artificiais. Entretanto, detecção e rastreamento de características naturais é mandatório ou desejável em alguns cenários de aplicação de Realidade Aumentada. A detecção e o rastreamento de objetos a partir de características naturais pode fazer uso de um modelo 3D do objeto obtido a priori. Se tal modelo não está disponível, ele pode ser adquirido usando reconstrução 3D, por exemplo. Nesse caso, um sensor RGB-D pode ser usado, que se tornou nos últimos anos um produto de fácil acesso aos usuários em geral. Ele provê uma imagem em cores e uma imagem de profundidade da cena e, além de ser usado para modelagem de objetos, também pode oferecer informações importantes para a detecção e o rastreamento de objetos em tempo real. Nesse contexto, o trabalho proposto neste documento tem por finalidade investigar o uso de sensores RGB-D de consumo para detecção e estimação de pose de objetos a partir de características naturais, com o propósito de usar tais técnicas para desenvolver aplicações de Realidade Aumentada. Dois métodos baseados em retificação auxiliada por profundidade são propostos, que transformam características extraídas de uma imagem em cores para uma vista canônica usando dados de profundidade para obter uma representação invariante a rotação, escala e distorções de perspectiva. Enquanto um método é adequado a objetos texturizados, tanto planares como não-planares, o outro método foca em objetos planares não texturizados. Avaliações qualitativas e quantitativas dos métodos propostos são realizadas, mostrando que eles podem obter resultados melhores que alguns métodos existentes para detecção e estimação de pose de objetos, especialmente ao lidar com poses oblíquas.
Augmented Reality systems are able to perform real-time 3D registration of virtual and real objects, which consists in correctly positioning the virtual objects with respect to the real ones such that the virtual elements seem to be real. A very popular way to perform this registration is using video based object detection and tracking with planar fiducial markers. Another way of sensing the real world using video is by relying on natural features of the environment, which is more complex than using artificial planar markers. Nevertheless, natural feature detection and tracking is mandatory or desirable in some Augmented Reality application scenarios. Object detection and tracking from natural features can make use of a 3D model of the object which was obtained a priori. If such model is not available, it can be acquired using 3D reconstruction. In this case, an RGB-D sensor can be used, which has become in recent years a product of easy access to general users. It provides both a color image and a depth image of the scene and, besides being used for object modeling, it can also offer important cues for object detection and tracking in real-time. In this context, the work proposed in this document aims to investigate the use of consumer RGB-D sensors for object detection and pose estimation from natural features, with the purpose of using such techniques for developing Augmented Reality applications. Two methods based on depth-assisted rectification are proposed, which transform features extracted from the color image to a canonical view using depth data in order to obtain a representation invariant to rotation, scale and perspective distortions. While one method is suitable for textured objects, either planar or non-planar, the other method focuses on texture-less planar objects. Qualitative and quantitative evaluations of the proposed methods are performed, showing that they can obtain better results than some existing methods for object detection and pose estimation, especially when dealing with oblique poses.

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Costa, João Paulo Carvalho Lustosa da. « Parameter estimation techniques for multi-dimensional array signal processing ». Aachen Shaker, 2010. http://d-nb.info/1000960765/04.

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Dangl, Markus A. « Iterative estimation and detection for single carrier block transmission ». Tönning Lübeck Marburg Der Andere Verl, 2007. http://d-nb.info/986923419/04.

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Sawo, Felix. « Nonlinear state and parameter estimation of spatially distributed systems ». Karlsruhe Univ.-Verl. Karlsruhe, 2009. http://d-nb.info/994500211/04.

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Knievel, Christopher [Verfasser]. « Multi-Dimensional Channel Estimation for MIMO-OFDM / Christopher Knievel ». Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/1063330807/34.

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Schneider, René [Verfasser]. « Iterative Partition-Based Moving-Horizon State Estimation / René Schneider ». Aachen : Shaker, 2017. http://d-nb.info/1138178179/34.

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Norrenbrock, Christoph [Verfasser]. « Instrumental Quality Estimation for Synthesized Speech Signals / Christoph Norrenbrock ». Aachen : Shaker, 2014. http://d-nb.info/1050341694/34.

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Körbitz, Paul [Verfasser]. « Aspects of estimation uncertainty in risk management / Paul Körbitz ». Ulm : Universität Ulm. Fakultät für Mathematik und Wirtschaftswissenschaften, 2013. http://d-nb.info/1038005051/34.

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Jensen, Katrin [Verfasser]. « Estimation and optimization problems in power markets / Katrin Jensen ». Ulm : Universität Ulm. Fakultät für Mathematik und Wirtschaftswissenschaften, 2012. http://d-nb.info/1024126935/34.

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Patschkowski, Tim [Verfasser], et Angelika [Akademischer Betreuer] Rohde. « New approaches to locally adaptive nonparametric estimation and inference ». Freiburg : Universität, 2017. http://d-nb.info/1135134197/34.

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Rath, Alexander [Verfasser]. « Global Error Estimation for Stiff Differential Equations / Alexander Rath ». München : Verlag Dr. Hut, 2017. http://d-nb.info/1135596077/34.

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Schopp, Patrick [Verfasser], et Yiannos [Akademischer Betreuer] Manoli. « State estimation, calibration, and self-calibration for accelerometer arrays ». Freiburg : Universität, 2018. http://d-nb.info/1166053725/34.

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Sümer, Ömer [Verfasser]. « Multimodal Visual Sensing : Automated Estimation of Engagement / Ömer Sümer ». Tübingen : Universitätsbibliothek Tübingen, 2021. http://d-nb.info/1230796487/34.

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