Dissertations / Theses: 'Tree motion'

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Kowalska, Jolanta. "Tree of life dance : cultural universals in motion /." Warsaw : Institute of the history of material culture, Polish academy of sciences, 1991. http://catalogue.bnf.fr/ark:/12148/cb374876094.

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Mathew, Reji Kuruvilla Electrical Engineering &amp Telecommunications Faculty of Engineering UNSW. "Quad-tree motion models for scalable video coding applications." Awarded by:University of New South Wales. Electrical Engineering & Telecommunications, 2009. http://handle.unsw.edu.au/1959.4/44600.

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Modeling the motion that occurs between frames of a video sequence is a key component of video coding applications. Typically it is not possible to represent the motion between frames by a single model and therefore a quad-tree structure is employed where smaller, variable size regions or blocks are allowed to take on separate motion models. Quad-tree structures however suffer from two fundamental forms of redundancy. First, quad-trees exhibit structural redundancy due to their inability to exploit the dependence between neighboring leaf nodes with different parents. The second form of redundancy is due to the quad-tree structure itself being limited to capture only horizontal and vertical edge discontinuities at dyadically related locations; this means that general discontinuities in the motion field, such as those caused by boundaries of moving objects, become difficult and expensive to model. In our work, we address the issue of structural redundancy by introducing leaf merging. We describe how the intuitively appealing leaf merging step can be incorporated into quad-tree motion representations for a range motion modeling contexts. In particular, the impact of rate-distortion (R-D) optimized merging for two motion coding schemes, these being spatially predictive coding, as used by H.264, and hierarchical coding, are considered. Our experimental results demonstrate that the merging step can provide significant gains in R-D performance for both the hierarchical and spatial prediction schemes. Hierarchical coding has the advantage that it offers scalable access to the motion information; however due to the redundancy it introduces hierarchical coding has not been traditionally pursued. Our work shows that much of this redundancy can be mitigated with the introduction of merging. To enable scalable decoding, we employ a merging scheme which ensures that the dependencies introduced via merging can be hierarchically decoded. Theoretical investigations confirm the inherent advantages of leaf merging for quad-tree motion models. To enable quad-tree structures to better model motion discontinuity boundaries, we introduce geometry information to the quad-tree representation. We choose to model motion and geometry using separate quad-tree structures; thereby enabling each attribute to be refined separately. We extend the leaf merging paradigm to incorporate the dual tree structure allowing regions to be formed that have both motion and geometry attributes, subject to rate-distortion optimization considerations. We employ hierarchical coding for the motion and geometry information and ensure that the merging process retains the property of resolution scalability. Experimental results show that the R-D performance of the merged dual tree representation, is significantly better than conventional motion modeling schemes. Theoretical investigations show that if both motion and boundary geometry can be perfectly modeled, then the merged dual tree representation is able to achieve optimal R-D performance. We explore resolution scalability of merged quad-tree representations. We consider a modified Lagrangian cost function that takes into account the possibility of scalable decoding. Experimental results reveal that the new cost objective can considerably improve scalability performance without significant loss in overall efficiency and with competitive performance at all resolutions.

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Fredriksson, Mattias. "Tree structured neural network hierarchy for synthesizing throwing motion." Thesis, Blekinge Tekniska Högskola, Institutionen för datavetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-20812.

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Realism in animation sequences requires movements to be adapted to changing environments within the virtual world. To enhance visual experiences from animated characters, research is being focused on recreating realistic character movement adapted to surrounding environment within the character's world. Existing methods as applied to the problem of controlling character animations are often poorly suited to the problem as they focus on modifying and adapting static sequences, favoring responsiveness and reaching the motion objective rather than realism in characters movements. Algorithms for synthesizing motion sequences can then bridge the gap between motion quality and responsiveness, and recent methods have shown to open the possibility to recreate specific motions and movement patterns. Effectiveness of proposed methods to synthesize motion can however be questioned, particularly due to the sparsity and quality of evaluations between methods. An issue which is further complicated by variations in learning tasks and motion data used to train models. Rather than directly propose a new synthesis method, focus is put on refuting existing methods by applying them to the task of synthesizing objective-oriented motion involving the action of throwing a ball. To achieve this goal, two experiments are designed. The first experiment evaluates if a phase-functioned neural network (PFNN) model based on absolute joint configurations can generate objective oriented motion. To achieve this objective, a separate approach utilizing a hierarchy of phase-function networks is designed and implemented. By comparing application of the two methods on the learning task, the proposed hierarchy model showed significant improvement regarding the ability to fit generated motion to intended end effector trajectories. To be able to refute the idea of using dense feed-forward neural networks, a second experiment is performed comparing PFNN and feed-forward based network hierarchies. Outcome from the experiment show significant differences in favor for the hierarchy model utilizing phase-function networks. To facilitate experimentation, objective oriented motion data for training network models are obtained by researching and implementing methods for processing optical motion capture data over repeated practices of over-arm ball throws. Contribution is then threefold: creation of a dataset containing motion sequences of ball throwing actions, evaluation of PFNN on the task of learning sequences of objective oriented motion, and definition of a hierarchy based neural network model applicable to the motion synthesis task.

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Miller, Jordan Mitchell. "Estimation of individual tree metrics using structure-from-motion photogrammetry." Thesis, University of Canterbury. Geography, 2015. http://hdl.handle.net/10092/11035.

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The deficiencies of traditional dendrometry mean improvements in methods of tree mensuration are necessary in order to obtain accurate tree metrics for applications such as resource appraisal, and biophysical and ecological modelling. This thesis tests the potential of SfM-MVS (Structure-fromMotion with Multi-View Stereo-photogrammetry) using the software package PhotoScan Professional, for accurately determining linear (2D) and volumetric (3D) tree metrics. SfM is a remote sensing technique, in which the 3D position of objects is calculated from a series of photographs, resulting in a 3D point cloud model. Unlike other photogrammetric techniques, SfM requires no control points or camera calibration. The MVS component of model reconstruction generates a mesh surface based on the structure of the SfM point cloud. The study was divided into two research components, for which two different groups of study trees were used: 1) 30 small, potted ‘nursery’ trees (mean height 2.98 m), for which exact measurements could be made and field settings could be modified, and; 2) 35 mature ‘landscape’ trees (mean height 8.6 m) located in parks and reserves in urban areas around the South Island, New Zealand, for which field settings could not be modified. The first component of research tested the ability of SfM-MVS to reconstruct spatially-accurate 3D models from which 2D (height, crown spread, crown depth, stem diameter) and 3D (volume) tree metrics could be estimated. Each of the 30 nursery trees was photographed and measured with traditional dendrometry to obtain ground truth values with which to evaluate against SfM-MVS estimates. The trees were destructively sampled by way of xylometry, in order to obtain true volume values. The RMSE for SfM-MVS estimates of linear tree metrics ranged between 2.6% and 20.7%, and between 12.3% and 47.5% for volumetric tree metrics. Tree stems were reconstructed very well though slender stems and branches were reconstructed poorly. The second component of research tested the ability of SfM-MVS to reconstruct spatially-accurate 3D models from which height and DBH could be estimated. Each of the 35 landscape trees, which varied in height and species, were photographed, and ground truth values were obtained to evaluate against SfM-MVS estimates. As well as this, each photoset was thinned to find the minimum number of images required to achieve total image alignment in PhotoScan and produce an SfM point cloud (minimum photoset), from which 2D metrics could be estimated. The height and DBH were estimated by SfM-MVS from the complete photosets with RMSE of 6.2% and 5.6% respectively. The height and DBH were estimated from the minimum photosets with RMSE of 9.3% and 7.4% respectively. The minimum number of images required to achieve total alignment was between 20 and 50. There does not appear to be a correlation between the minimum number of images required for alignment and the error in the estimates of height or DBH (R2 =0.001 and 0.09 respectively). Tree height does not appear to affect the minimum number of images required for image alignment (R 2 =0.08).

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Selino, Anthony Frank. "Coherent Turbulence: Synthesizing tree motion in the wind using CFD and noise." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/3015.

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Animating trees in wind has long been a problem in computer graphics. Progress on this problem is important for both visual effects and biomechanics and may inform future work on two-way coupling between turbulent flows and deformable objects. Synthetic turbulence added to a coarse fluid simulation has been used to produce convincing animations of turbulent flows, but only considers one-way coupling between fluid and solid. We produce accurate animations of tree motion by creating a two-way coupling between synthetic turbulence and semipermeable proxy geometry. The resulting animations exhibit global wind sheltering effects and branch tips have motion paths which match paths collected from branch tips using motion capture.

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Sari, Huseyin. "Motion Estimation Using Complex Discrete Wavelet Transform." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1223205/index.pdf.

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The estimation of optical flow has become a vital research field in image sequence analysis especially in past two decades, which found applications in many fields such as stereo optics, video compression, robotics and computer vision. In this thesis, the complex wavelet based algorithm for the estimation of optical flow developed by Magarey and Kingsbury is implemented and investigated. The algorithm is based on a complex version of the discrete wavelet transform (CDWT), which analyzes an image through blocks of filtering with a set of Gabor-like kernels with different scales and orientations. The output is a hierarchy of scaled and subsampled orientation-tuned subimages. The motion estimation algorithm is based on the relationship between translations in image domain and phase shifts in CDWT domain, which is satisfied by the shiftability and interpolability property of CDWT. Optical flow is estimated by using this relationship at each scale, in a coarse-to-fine (hierarchical) manner, where information from finer scales is used to refine the estimates from coarser scales. The performance of the motion estimation algorithm is investigated with various image sequences as input and the effects of the options in the algorithm like curvature-correction, interpolation kernel between levels and some parameter values like confidence threshold iv maximum number of CDWT levels and minimum finest level of detail are also experimented and discussed. The test results show that the method is superior to other well-known algorithms in estimation accuracy, especially under high illuminance variations and additive noise.

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Chang, Ming. "Example-Based Fluid Simulation." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20310.

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We present a novel method for example-based simulation of fluid flow. We reconstruct fluid animation from physically based fluid simulation examples. Our framework shows how to decompose a given series of fluid motion example data into small units and then recompose them. We capture the properties of local fluid behavior by dicing the fluid motion example data into sequences of fragments, which have smaller volume and shorter length. We build a database out of these fragments, and propose a matching strategy to generate new fluid animation. To achieve highly efficient database query, we project our fragments onto lower dimensional subspace using Principal Component Analysis (PCA) approach, and construct our data structure as a kd-tree by treating each fragment as a point in this subspace. Our method has been implemented in synthesizing both two-dimensional (2D) and three-dimensional (3D) fluid’s velocity fields.

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Mukora, Wanjiku Beatrice. "Disrupting binary divisions : representation of identity in Saikati and Battle of the sacred tree." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0016/MQ55002.pdf.

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Aumann, Craig Alvan. "Development, parameterization and numerical solution of an unsaturated flow model for water in the sapwood of a Douglas-fir tree /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/6374.

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Fredriksson, Tomas, and Rickard Svensson. "Analysis of machine learning for human motion pattern recognition on embedded devices." Thesis, KTH, Mekatronik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246087.

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With an increased amount of connected devices and the recent surge of artificial intelligence, the two technologies need more attention to fully bloom as a useful tool for creating new and exciting products. As machine learning traditionally is implemented on computers and online servers this thesis explores the possibility to extend machine learning to an embedded environment. This evaluation of existing machine learning in embedded systems with limited processing capa-bilities has been carried out in the specific context of an application involving classification of basic human movements. Previous research and implementations indicate that it is possible with some limitations, this thesis aims to answer which hardware limitation is affecting clas-sification and what classification accuracy the system can reach on an embedded device. The tests included human motion data from an existing dataset and included four different machine learning algorithms on three devices. Support Vector Machine (SVM) are found to be performing best com-pared to CART, Random Forest and AdaBoost. It reached a classification accuracy of 84,69% between six different included motions with a clas-sification time of 16,88 ms per classification on a Cortex M4 processor. This is the same classification accuracy as the one obtained on the host computer with more computational capabilities. Other hardware and machine learning algorithm combinations had a slight decrease in clas-sification accuracy and an increase in classification time. Conclusions could be drawn that memory on the embedded device affect which al-gorithms could be run and the complexity of data that can be extracted in form of features. Processing speed is mostly affecting classification time. Additionally the performance of the machine learning system is connected to the type of data that is to be observed, which means that the performance of different setups differ depending on the use case.
Antalet uppkopplade enheter ökar och det senaste uppsvinget av ar-tificiell intelligens driver forskningen framåt till att kombinera de två teknologierna för att både förbättra existerande produkter och utveckla nya. Maskininlärning är traditionellt sett implementerat på kraftfulla system så därför undersöker den här masteruppsatsen potentialen i att utvidga maskininlärning till att köras på inbyggda system. Den här undersökningen av existerande maskinlärningsalgoritmer, implemen-terade på begränsad hårdvara, har utförts med fokus på att klassificera grundläggande mänskliga rörelser. Tidigare forskning och implemen-tation visar på att det ska vara möjligt med vissa begränsningar. Den här uppsatsen vill svara på vilken hårvarubegränsning som påverkar klassificering mest samt vilken klassificeringsgrad systemet kan nå på den begränsande hårdvaran. Testerna inkluderade mänsklig rörelsedata från ett existerande dataset och inkluderade fyra olika maskininlärningsalgoritmer på tre olika system. SVM presterade bäst i jämförelse med CART, Random Forest och AdaBoost. Den nådde en klassifikationsgrad på 84,69% på de sex inkluderade rörelsetyperna med en klassifikationstid på 16,88 ms per klassificering på en Cortex M processor. Detta är samma klassifikations-grad som en vanlig persondator når med betydligt mer beräknings-resurserresurser. Andra hårdvaru- och algoritm-kombinationer visar en liten minskning i klassificeringsgrad och ökning i klassificeringstid. Slutsatser kan dras att minnet på det inbyggda systemet påverkar vilka algoritmer som kunde köras samt komplexiteten i datan som kunde extraheras i form av attribut (features). Processeringshastighet påverkar mest klassificeringstid. Slutligen är prestandan för maskininlärningsy-stemet bunden till typen av data som ska klassificeras, vilket betyder att olika uppsättningar av algoritmer och hårdvara påverkar prestandan olika beroende på användningsområde.

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Ismail, Ofa. "Planning Method for a Reversing Single Joint Tractor-Trailer System." Thesis, Linköpings universitet, Fordonssystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177800.

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This thesis investigates the design of a local planning method for a reversing single joint tractor-trailer system that can be used in a sampling-based motion planner. The motion planner used is a Rapidly-exploring Random Tree (RRT) developed by Scania. The main objective of a local planning method is to generate a feasible path between two poses, which is needed when expanding the search tree in an RRT. The local planning method described in this thesis uses a set of curves, similar to Reeds-Shepp curves, feasible for a single joint tractor-trailer system. The curves are found by solving a constrained optimization problem that adheres to the kinematic model of the system. The reference for the tractor is generated by discretizing the path between curves. The reference for the trailer is generated by simulating the mission backwards where the curve radiuses are used as input. Simulating the mission backwards circumvents the instability of the system when reversing. The generated references are then compared to references generated by a lattice-based motion planner. The length of the references generated by the RRT are smaller than those generated by the lattice-based motion planner in simple open environments. The RRT had issues finding a path in cases where the environment was complex while the lattice-based motion planner found a path in every scenario. The computational time was significantly lower for the RRT in all simulations. The RRT generates all references between any two given poses while the lattice-based motion planner approximate the start and goal poses to the closest vertex in the search-space. The references generated by the RRT did not perform optimally when small turns were needed along the curves due to the distance needed for maneuvering the tractor. Therefore, a new optimization problem has to be defined for which the small turns are considered.

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Bartozel, Zdeněk. "Plánování cesty v reálném čase." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402500.

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The thesis deals with the path planning and movement of the holonomic robot in a dynamic environment. The aim of this work is implementation of several algorithms based on Rapidly-explored random tree algorithm and their comparison in designed dynamic environment.

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Adam, Andrew. "Planning dynamic vehicle motion using move trees." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31505.

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Generating skilled and well-planned behaviours for autonomous agents is a challenging problem common to both computer animation and robotics. This thesis presents a system that uses motion graphs for online motion planning, resulting in skilled driving behaviours for a dynamic model of a car in a constrained environment. The result reproduces skilled driving behaviors. It is a particular challenge to get the cars to produce skidding-into-turn behaviors when approaching sharp corners, which can achieve the fastest speeds around a track. The techniques explored in this thesis are potentially generalizable to other dynamic vehicle behaviours, in computer games or simulations. We demonstrate that a well-formed move tree or motion graph, created from the output of a physics-based simulation can be used to produce realistic steering behaviours on a variety of tracks. We show that a finite-horizon A * search algorithm is well suited to this task. We have produced a number of smooth animations that demonstrate considerable anticipation and agility, be it through acceleration/deceleration around tricky obstacles, or a hard skidding turn into a corner after approaching at high speed. Finally, we offer a number of ways that we could speed up the algorithms for future work in this area.
Science, Faculty of
Computer Science, Department of
Graduate

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Acar, Esra. "Efficient index structures for video databases." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609322/index.pdf.

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Content-based retrieval of multimedia data has been still an active research area. The efficient retrieval of video data is proven a difficult task for content-based video retrieval systems. In this thesis study, a Content-Based Video Retrieval (CBVR) system that adapts two different index structures, namely Slim-Tree and BitMatrix, for efficiently retrieving videos based on low-level features such as color, texture, shape and motion is presented. The system represents low-level features of video data with MPEG-7 Descriptors extracted from video shots by using MPEG-7 reference software and stored in a native XML database. The low-level descriptors used in the study are Color Layout (CL), Dominant Color (DC), Edge Histogram (EH), Region Shape (RS) and Motion Activity (MA). Ordered Weighted Averaging (OWA) operator in Slim-Tree and BitMatrix aggregates these features to find final similarity between any two objects. The system supports three different types of queries: exact match queries, k-NN queries and range queries. The experiments included in this study are in terms of index construction, index update, query response time and retrieval efficiency using ANMRR performance metric and precision/recall scores. The experimental results show that using BitMatrix along with Ordered Weighted Averaging method is superior in content-based video retrieval systems.

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Guo, Peili. "Heuristic for vehicle motion planning with search trees." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-432185.

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Motion planning is an essential part of an autonomous system. It finds a sequence of actions for the vehicle to move from start to goal. In this thesis, we study the use of heuristic in the context of motion planning. We propose a heuristic method using a pre-computed heuristic look up table for sampling based motion planning method Rapidly-exploring random trees (RRT). The proposed method is successfully implemented and evaluated in nine different scenarios. We have found improvement in the quality of the path at a short time out in at least six out of the nine scenarios. In certain scenarios, we are able to observe up to 20% reduction of execution time and up to 90% of improvement of the path quality.

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Abbadi, Ahmad. "Expert Systems and Advanced Algorithms in Mobile Robots Path Planning." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-234415.

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Metody plánování pohybu jsou významnou součástí robotiky, resp. mobilních robotických platforem. Technicky je realizace plánování pohybu z globální úrovně převedena do posloupnosti akcí na úrovni specifické robotické platformy a definovaného prostředí, včetně omezení. V rámci této práce byla provedena recenze mnoha metod určených pro plánování cest, přičemž hlavním těžištěm byly metody založené na tzv. rychle rostoucích stromech (RRT), prostorovém rozkladu (CD) a využití fuzzy expertních systémů (FES). Dosažené výsledky, resp. prezentované algoritmy, využívají dostupné informace z pracovního prostoru mobilního robotu a jsou aplikovatelné na řešení globální pohybové trajektorie mobilních robotů, resp. k řešení specifických problémů plánování cest s omezením typu úzké koridory či překážky s proměnnou polohou v čase. V práci jsou představeny nové plánovací postupy využívající výhod algoritmů RRT a CD. Navržené metody jsou navíc efektivně rozšířeny s využitím fuzzy expertního systému, který zlepšuje jejich chování. Práce rovněž prezentuje řešení pro plánovací problémy typu identifikace úzkých koridorů, či významných oblastí prostoru řešení s využitím přístupů na bázi dekompozice prostoru. V řešeních jsou částečně zahrnuty sub-optimalizace nalezených cest založené na zkracování nalezené cesty a vyhlazování cesty, resp. nahrazení trajektorie hladkou křivkou, respektující lépe předpokládanou dynamiku mobilního zařízení. Všechny prezentované metody byly implementovány v prostředí Matlab, které sloužilo k simulačnímu ověření efektivnosti vlastních i převzatých metod a k návrhu prostoru řešení včetně omezení (překážky). Získané výsledky byly vyhodnoceny s využitím statistických přístupů v prostředí Minitab a Matlab.

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Leckman, Glen. "The use of the "Jesus" film and travelling evangelists a study of proclaiming the Word of God and its long-term effects /." Theological Research Exchange Network (TREN) Access this title online, 1988. http://dx.doi.org/10.2986/tren.017-0084.

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Ahmady, Phoulady Hady. "Brownian Motions and Scaling Limits of Random Trees." Thesis, Uppsala universitet, Matematisk statistik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-164700.

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Jin, Hanxiang. "Periodic Motions and Bifurcation Tree in a Periodically Excited Duffing Oscillator with Time-delay." Thesis, Southern Illinois University at Edwardsville, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1567592.

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Analytical solutions of periodic motions in a periodically excited, Duffing oscillator with a time-delayed displacement are developed through the Fourier series, and the stability and bifurcation of such periodic motions are discussed through eigenvalue analysis. The analytical bifurcation trees of period-1 motions to chaos in the time-delayed Duffing oscillator is presented through asymmetric period-1 to period-4 motions. Four independent symmetric period-3 motions were obtained. Two independent symmetric period-3 motions are not relative to chaos, while the other two includes bifurcation trees of period-3 motion to chaos, which are presented through period-3 to period-6 motions. Stable periodic motions are illustrated from numerical and analytical solutions. The appropriate initial history functions for periodic motions are analytically computed from the analytical solutions of periodic motions. Without the appropriate initial history functions, such a time-delayed system cannot yield periodic motions directly.

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Lin, Shen. "Marche aléatoire indexée par un arbre et marche aléatoire sur un arbre." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112379/document.

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L’objet de cette thèse est d’étudier plusieurs modèles probabilistes reliant les marches aléatoires et les arbres aléatoires issus de processus de branchement critiques.Dans la première partie, nous nous intéressons au modèle de marche aléatoire à valeurs dans un réseau euclidien et indexée par un arbre de Galton–Watson critique conditionné par la taille. Sous certaines hypothèses sur la loi de reproduction critique et la loi de saut centrée, nous obtenons, dans toutes les dimensions, la vitesse de croissance asymptotique du nombre de points visités par cette marche, lorsque la taille de l’arbre tend vers l’infini. Ces résultats nous permettent aussi de décrire le comportement asymptotique du nombre de points visités par une marche aléatoire branchante, quand la taille de la population initiale tend vers l’infini. Nous traitons également en parallèle certains cas où la marche aléatoire possède une dérive constante non nulle.Dans la deuxième partie, nous nous concentrons sur les propriétés fractales de la mesure harmonique des grands arbres de Galton–Watson critiques. On comprend par mesure harmonique la distribution de sortie, hors d’une boule centrée à la racine de l’arbre, d’une marche aléatoire simple sur cet arbre. Lorsque la loi de reproduction critique appartient au domaine d’attraction d’une loi stable, nous prouvons que la masse de la mesure harmonique est asymptotiquement concentrée sur une partie de la frontière, cette partie ayant une taille négligeable par rapport à celle de la frontière. En supposant que la loi de reproduction critique a une variance finie, nous arrivons à évaluer la masse de la mesure harmonique portée par un sommet de la frontière choisi uniformément au hasard
The aim of this Ph. D. thesis is to study several probabilistic models linking the random walks and the random trees arising from critical branching processes.In the first part, we consider the model of random walk taking values in a Euclidean lattice and indexed by a critical Galton–Watson tree conditioned by the total progeny. Under some assumptions on the critical offspring distribution and the centered jump distribution, we obtain, in all dimensions, the asymptotic growth rate of the range of this random walk, when the size of the tree tends to infinity. These results also allow us to describe the asymptotic behavior of the range of a branching random walk, when the size of the initial population goes to infinity. In parallel, we treat likewise some cases where the random walk has a non-zero constant drift.In the second part, we focus on the fractal properties of the harmonic measure on large critical Galton–Watson trees. By harmonic measure, we mean the exit distribution from a ball centered at the root of the tree by simple random walk on this tree. If the critical offspring distribution is in the domain of attraction of a stable distribution, we prove that the mass of the harmonic measure is asymptotically concentrated on a boundary subset of negligible size with respect to that of the boundary. Assuming that the critical offspring distribution has a finite variance, we are able to calculate the mass of the harmonic measure carried by a random vertex uniformly chosen from the boundary

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Ma, Haolin. "Periodic Motions and Bifurcation Trees in a Parametric Duffing Oscillator." Thesis, Southern Illinois University at Edwardsville, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10242344.

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This thesis is a study of bifurcation trees of periodic motions in a parametric Duffing oscillator. The bifurcation trees from period-1 to period-4 motions are investigated by a semi-analytic method. For the semi-analytic method, the discretization of differential equations of nonlinear dynamical systems is obtained to attain the implicit mapping structure. Following the development of implicit mapping structure, the periodic nodes of periodic motions are computed. The stability and bifurcation conditions are carried out by the eigenvalue analysis. For a better understanding of nonlinear behaviors of periodic motions, the harmonic frequency-amplitude characteristics are presented by the finite Fourier series. Numerical simulations are illustrated to verify the analytical predictions. Based on the comparison of numerical and analytical result, the trajectory, time history, harmonic amplitude and harmonic phase plots of period-1 to period-4 motions are completed.

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22

Grepne-Takle, Ruben. "Simulator Studies on the Effectiveness of a Collision Avoidance Display in True Motion." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-15565.

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A major concern for the navigator during a voyage is collision avoidance. The IBS (Integrated Bridge System) has a large quantity of marine traffic data available. Complicated and congested traffic may challenge the navigational safety. It is of vital importance that the navigator is equipped with the necessary tools to be able to do a fast assessment of the situation. Visual observation, ARPA and AIS are the main information sources today. The introduction of a collision avoidance display that focus on real-time presentation of danger areas in true motion enables the navigator to judge collision risk for any acquired target and simultaneously identify suitable evasive manoeuvres. The simulator study focused on evaluating two collision avoidance displays, CDP (Collision Danger Presentation) and RTM (Room To Manoeuvre) versus standard ARPA. In addition CDP versus RTM was evaluated. The subjects consisted of experienced navigators from the Royal Norwegian Navy and final year marine cadets from the Royal Norwegian Naval Academy. The study was conducted on a full mission bridge simulator by three trial scenarios with increasing difficulty level. The evaluation was based on descriptive methods and parametric tests. A reflection on making decisions in collision avoidance is given in the thesis. The excellence of both collision avoidance displays was proven, where the major benefit was reduction in reaction time. Between the populations it was found that the cadets benefitted from the collision avoidance displays in both the simple and the congested scenario, whilst the experienced navigators mainly improved their performance in the congested scenario. The evaluation of CDP versus RTM indicated that the CDP display was preferred. As for the collision avoidance tools existing today, the CDP does not take into account the COLREGs. This aspect is, and will in the nearest future, be the navigator’s task to incorporate in his choice of evasive manoeuvres. Proposals for improvement of the beta version the collision avoidance display are given in the end of the document.

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23

Fazeli, Neishabour Sepideh [Verfasser], Stefan [Akademischer Betreuer] Treue, and Peter [Akademischer Betreuer] Dechent. "Attention modulation of complex motion patterns in human visual cortex / Sepideh Fazeli Neishabour. Gutachter: Stefan Treue ; Peter Dechent. Betreuer: Stefan Treue." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://d-nb.info/1064148239/34.

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24

Stein, Maximilian [Verfasser], Uwe [Akademischer Betreuer] Mattler, Uwe [Gutachter] Mattler, and Stefan [Gutachter] Treue. "Spatial and temporal dependencies of the motion bridging effect: Investigations of an illusory motion / Maximilian Stein ; Gutachter: Uwe Mattler, Stefan Treue ; Betreuer: Uwe Mattler." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1211173658/34.

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25

Sorwar, Golam 1969. "A novel distance-dependent thresholding strategy for block-based performance scalability and true object motion estimation." Monash University, Gippsland School of Computing and Information Technology, 2003. http://arrow.monash.edu.au/hdl/1959.1/5510.

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26

Lindström, Stefan. "Motion – och föreningsaktiviteter bland barn i årskurs 5 – 6 på tre skolor i Malmö kommun." Thesis, Malmö högskola, Lärarutbildningen (LUT), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-34157.

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För många skolor är daglig motion ett omdiskuterat ämne. Som verksam pedagog är det viktigt att nå ut med idrottsämnets innebörd till alla elever och framför allt till de som bäst behöver aktivera sig. Jag har skrivit ett arbete som handlar om barns motion- och föreningsaktiviteter i två diametralt olika stadsdelar i Malmö. Jag har studerat litteratur och gjort en enkätundersökning för att få ett svar på min problemformulering. Undersökningen har ägt rum på tre skolor i Malmö, där jag har gjort enkätundersökningar, det vill säga den kvantitativa metoden bland elever i årskurs fem och sex på skolorna Nydalaskolan, Ängslättskolan och Sundsbroskolan. Min utgångspunkt i examensarbetet är att undersöka om bakomliggande faktorer som boendemiljö, etnicitet och klass kan påverka barns motion- och föreningsaktiviteter. Problemformuleringen som jag har ställt är följande: Min problemformulering i den här undersökningen är att jämföra två skolor i Malmö, nämligen Nydalaskolan med Sundsbroskolan/Ängslättskolan som har fler idrottstimmar/vecka i skolan. Nydalaskolan har två idrottstimmar per vecka. Sundsbroskolan och Ängslättskolan är med i Bunkefloprojektet, det innebär att de varje dag har minst 45 minuter fysisk aktivitet. Är de sistnämnda eleverna mer fysiskt aktiva på sin fritid jämfört med dem som har ett mindre antal idrottstimmar/vecka, och vad beror det på i så fall? Mitt resultat från undersökningen visar att 55,4 % av eleverna från Nydalaskolan är aktiva med någon idrott på sin fritid. Av 74 tillfrågade elever på Nydalaskolan svarade 51,4 % att de var medlem i någon idrottsförening. De populäraste idrottsaktiviteterna på skolan är fotboll, samt någon annan idrott än de förslagna idrotterna på enkäten till exempel kampsport och friidrott. Den tredje populäraste idrottsaktiviteten hos eleverna är ridning. Jämför man skolorna finner man att Ängslättskolan/Sundsbroskolans elever är betydligt aktivare inom föreningslivet än vad Nydalaskolans elever är, samma sak gäller också när det gäller elevernas motionsvanor på fritiden. Detta stämmer väl överens med den hypotes som jag ställt.
Sporting activity among grade 5 – 6 students in three Malmoe schools.

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27

Bigot, Thomas. "Recherche automatisée de motifs dans les arbres phylogénétiques." Phd thesis, Université Claude Bernard - Lyon I, 2013. http://tel.archives-ouvertes.fr/tel-01044878.

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La phylogénie permet de reconstituer l'histoire évolutive de séquences ainsi que des espèces qui les portent. Les récents progrès des méthodes de séquençage ont permis une inflation du nombre de séquences disponibles et donc du nombre d'arbres de gènes qu'il est possible de construire. La question qui se pose est alors d'optimiser la recherche d'informations dans ces arbres. Cette recherche doit être à la fois exhaustive et efficace. Pour ce faire, mon travail de thèse a consisté en l'écriture puis en l'utilisation d'un ensemble de programmes capables de parcourir et d'annoter les arbres phylogénétiques. Cet ensemble de programmes porte le nom de TPMS (Tree Pattern Matching Suite). Le premier de ces programmes (tpms_query) permet d'effectuer l'interrogation de collections à l'aide d'un formalisme dédie. Les possibilités qu'il offre sont : La détection de transferts horizontaux : Si un arbre de gènes présente une espèce branchée dans un arbre au milieu d'un groupe monophylétique d'espèces avec lesquelles elle n'est pas apparentée, on peut supposer qu'il s'agit d'un transfert horizontal, si ces organismes sont des procaryotes ou des eucaryotes unicellulaires. La détection d'orthologie : Si une partie d'un arbre de gènes correspond exactement à l'arbre des espèces, on peut alors supposer que ces gènes sont un ensemble de gènes d'orthologues. La validation de phylogénies connues : Quand l'arbre des espèces donne lieu à des débats, il peut est possible d'interroger une large collection d'arbres de gènes pour voir combien de familles de gènes correspondent à chaque hypothèse. Un autre programme, tpms_computations, permet d'effectuer des opérations en parallèle sur tous les arbres, et propose notamment l'enracinement automatique des arbres via différents critères, ainsi que l'extraction de sous arbres d'orthologues (séquence unique par espèce). Il propose aussi une méthode de détection automatique d'incongruences. La thèse présente le contexte, les différents algorithmes à la base de ces programmes, ainsi que plusieurs utilisations qui en ont été faites

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Xing, Siyuan. "Periodic Motions and Bifurcation Trees in a Periodically Excited Duffing Oscillator with Time-delay." Thesis, Southern Illinois University at Edwardsville, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10147051.

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In this paper, bifurcation trees of periodic motions in a periodically forced, time-delayed, hardening Duffing oscillator are analytically predicted by a semi-analytical method. Such a semi-analytical method is based on the differential equation discretization of the time-delayed, non-linear dynamical system. Bifurcation trees for the stable and unstable solutions of periodic motions to chaos in such a time-delayed, Duffing oscillator are achieved analytically. From the finite discrete Fourier series, harmonic frequency-amplitude curves for stable and unstable solutions of period-1 to period-4 motions are developed for a better understanding of quantity levels, singularity and catastrophes of harmonic amplitudes in the frequency domain. From the analytical prediction, numerical results of periodic motions in the time-delayed, hardening Duffing oscillator are completed. Through the numerical illustrations, the complexity and asymmetry of period-1 motions to chaos in nonlinear dynamical systems are strongly dependent on the distributions and quantity levels of harmonic amplitudes. With the quantity level increases of specific harmonic amplitudes, effects of the corresponding harmonics on the periodic motions become strong, and the certain complexity and asymmetry of periodic motion and chaos can be identified through harmonic amplitudes with higher quantity levels.

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29

Bernardi, Daniel. "Star trek and history : race-ing toward a white future /." New Brunswick, NJ [u.a.] : Rutgers University Press, 1999. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=018615232&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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30

Dikbas, Salih. "A low-complexity approach for motion-compensated video frame rate up-conversion." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42730.

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Video frame rate up-conversion is an important issue for multimedia systems in achieving better video quality and motion portrayal. Motion-compensated methods offer better quality interpolated frames since the interpolation is performed along the motion trajectory. In addition, computational complexity, regularity, and memory bandwidth are important for a real-time implementation. Motion-compensated frame rate up-conversion (MC-FRC) is composed of two main parts: motion estimation (ME) and motion-compensated frame interpolation (MCFI). Since ME is an essential part of MC-FRC, a new fast motion estimation (FME) algorithm capable of producing sub-sample motion vectors at low computational-complexity has been developed. Unlike existing FME algorithms, the developed algorithm considers the low complexity sub-sample accuracy in designing the search pattern for FME. The developed FME algorithm is designed in such a way that the block distortion measure (BDM) is modeled as a parametric surface in the vicinity of the integer-sample motion vector; this modeling enables low computational-complexity sub-sample motion estimation without pixel interpolation. MC-FRC needs more accurate motion trajectories for better video quality; hence, a novel true-motion estimation (TME) algorithm targeting to track the projected object motion has been developed for video processing applications, such as motion-compensated frame interpolation (MCFI), deinterlacing, and denoising. Developed TME algorithm considers not only the computational complexity and regularity but also memory bandwidth. TME is obtained by imposing implicit and explicit smoothness constraints on block matching algorithm (BMA). In addition, it employs a novel adaptive clustering algorithm to keep the low-complexity at reasonable levels yet enable exploiting more spatiotemporal neighbors. To produce better quality interpolated frames, dense motion field at the interpolation instants are obtained for both forward and backward motion vectors (MVs); then, bidirectional motion compensation using forward and backward MVs is applied by mixing both elegantly.

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31

Arslan, Oktay. "Machine learning and dynamic programming algorithms for motion planning and control." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54317.

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Robot motion planning is one of the central problems in robotics, and has received considerable amount of attention not only from roboticists but also from the control and artificial intelligence (AI) communities. Despite the different types of applications and physical properties of robotic systems, many high-level tasks of autonomous systems can be decomposed into subtasks which require point-to-point navigation while avoiding infeasible regions due to the obstacles in the workspace. This dissertation aims at developing a new class of sampling-based motion planning algorithms that are fast, efficient and asymptotically optimal by employing ideas from Machine Learning (ML) and Dynamic Programming (DP). First, we interpret the robot motion planning problem as a form of a machine learning problem since the underlying search space is not known a priori, and utilize random geometric graphs to compute consistent discretizations of the underlying continuous search space. Then, we integrate existing DP algorithms and ML algorithms to the framework of sampling-based algorithms for better exploitation and exploration, respectively. We introduce a novel sampling-based algorithm, called RRT#, that improves upon the well-known RRT* algorithm by leveraging value and policy iteration methods as new information is collected. The proposed algorithms yield provable guarantees on correctness, completeness and asymptotic optimality. We also develop an adaptive sampling strategy by considering exploration as a classification (or regression) problem, and use online machine learning algorithms to learn the relevant region of a query, i.e., the region that contains the optimal solution, without significant computational overhead. We then extend the application of sampling-based algorithms to a class of stochastic optimal control problems and problems with differential constraints. Specifically, we introduce the Path Integral - RRT algorithm, for solving optimal control of stochastic systems and the CL-RRT# algorithm that uses closed-loop prediction for trajectory generation for differential systems. One of the key benefits of CL-RRT# is that for many systems, given a low-level tracking controller, it is easier to handle differential constraints, so complex steering procedures are not needed, unlike most existing kinodynamic sampling-based algorithms. Implementation results of sampling-based planners for route planning of a full-scale autonomous helicopter under the Autonomous Aerial Cargo/Utility System Program (AACUS) program are provided.

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32

Stephan, Valeska Marija [Verfasser], Stefan [Akademischer Betreuer] Treue, Alexander [Akademischer Betreuer] Gail, and Julia [Akademischer Betreuer] Fischer. "The influence of attention on motion processing / Valeska Marija Stephan. Gutachter: Alexander Gail ; Julia Fischer. Betreuer: Stefan Treue." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044770627/34.

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33

Ketonen, Joakim, and Daniel Walldén. "Motiv till fusioner : en jämförelse mellan branscher utifrån tre perspektiv." Thesis, Linköping University, Department of Management and Economics, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1040.

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During the twentieth century, mergers&aquisitions have occured in waves where times of low activityfrequently has turned into periods of high activity. M&A:s have been of increasing numbers and growing size, which was extra evident during the last wave during the 1990:s. What are the motives that has made M&A such a widely used strategy? Are there similarities within and across industries regarding merger motives? The empirical material consists of primary and secundary data collected from two mergers in three industries respectively; manufacturing, banking and IT. The analysis make use of three different perspectives, the reason for this being to create understanding and furthermore illuminate the complexity of the problem. The results clearly demonstrate similarities in merger motives within the industries, but also give some support for similarities across the industries. Furthermore, using a multi perspective approach has proved to be a good way of illuminating the problem.

Under 1900-talet har företagsfusioner förekommit i vågformade mönster där tider med lugnare aktivitet har avlösts av tider med något som närmast kan beskrivas som fusionsyra. Fusionsvågornas antal och storlek har efterhand ökat och vågtopparna har vuxit sig allt högre, något som inte minst varit tydligt under de senaste 6-7 åren Vilka är de motiv som har gjort fusioner till ett så vanligt förekommande strategiskt agerande? Finns det likheter inom och mellan branscher avseende motiven att fusionera? Det empiriska materialet består av primär- och sekundärdata insamlat från sex fusioner fördelat på tre branscher; tillverkningsindustrin, bankbranschen och IT-branschen. I analysen används tre skilda perspektiv, och syftet med detta är att skapa bred förståelse och belysa komplexiteten i fenomenet. Resultaten visar på tydliga likheter i motiv inom branscher, samt att det även finns vissa motiv som är branschöverskridande. Vidare innebär de tre perspektiven ett medningsfullt sätt att skapa förståelse och belysa komplexiteten kring motiv till fusioner.

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Söderholm, Richard, and Simon Birging. "Ett maratonarbete : en trendstudie om konditionens förändring på tre olika svenska populationer." Thesis, Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:gih:diva-502.

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Syfte och frågeställningar

Syftet med uppsatsen är att undersöka GIH-studenters kondition och jämföra den trend som finns på GIH gentemot trender för konditionen hos mönstrande samt löpare i Stockholm Marathon. De frågeställningar som användes var:

1. Hur har GIH-studenters maximala syreupptagningsförmåga förändrats från 1977 till 2008?

2. Hur har mäns arbetskapacitet under mönstringen förändrats mellan åren 1969-83 samt 1986-93?

3. Hur har medeltiden förändrats för de löpare som deltog i och slutförde Stockholm Marathon mellan åren 1979-2008?

Metod

Dels deltog vi i framtagande av ny data i egenskaper av testledare i ett projekt för att undersöka GIH-studenters maximala syreupptagningsförmåga under hösten 2008 (n=28). Dessa data jämfördes sedan med tidigare framtagna data från ett liknande test på GIH-studenter från 1977 (n=44). Resterande del av undersökningen var bearbetning av befintlig data. Totalt studerades 183 216 löpare i Stockholm Marathon samt i snitt 45 000 mönstrande för varje studerat år.

Resultat

De resultat som framkom av studien var att en negativ utveckling gick att utläsa på GIH-studenternas maximala syreupptagningsförmåga, från 4,50 l O2/min hos männen till 4,24 l O2/min, medan utvecklingen hos kvinnorna var minimal, 2,88 l O2/min till 2,86 l O2/min. Utvecklingen blev större när korrelation mellan vikt och syreupptagningsförmåga gjorts, 61,6ml O2/min*min-1 till 55,6ml O2/min*min-1 för männen medan en förändring från 47,8ml O2/min*min-1 till 44,9ml O2/min*min-1 hos kvinnorna kunde konstateras. Hos mönstrande män var utvecklingen tvådelad; under åren 1969-83 ökade arbetskapaciteten per kilo kroppsvikt något, 3,53W/kg till 3,69W/kg, medan det skedde en minskning mellan 1986 och 1993; 4,34W/kg till 4,17W/kg. För löpare i Stockholm Marathon ökade sluttiden stadigt mellan 1979 och 2008 från att ha legat i medel på 215 min för herrar 1979 till 243 min 2008. Motsvarande tider för damer låg 1979 på 233 min för att stiga till 257 min 2008.

Slutsats

Utvecklingen för konditionen hos GIH-studenter ligger väl i linje med befintlig forskning som visar på en försämring hos den manliga delen hos befolkningen mot en svagt negativ eller oförändrad kondition hos kvinnorna. Denna trend går dock inte att utläsa på bearbetad mönstringsdata, vars förändring var för liten för att statistiskt kunna säkerställas. En tydlig försämring uppmättes av sluttiden i Stockholm Marathon vilket tros bero på en försämring i konditionen hos löparna. De framtagna resultaten bekräftas i stort av tidigare forskning som visar på en försämring av konditionen men samtidigt visar statistik på att träningsfrekvensen inte sjunkit. Därför drar vi slutsatsen att en annan typ av träning är mer vanligt förekommande idag, såsom koordinations- och styrketräning. Detta är dock inte säkerställt utan en slutsats baserad på forskningsläget.

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35

Torres, Álvarez Hernán. "Reflexiones con motivo de los tres primeros años de aplicación del Protocolo de Kioto." IUS ET VERITAS, 2015. http://repositorio.pucp.edu.pe/index/handle/123456789/122592.

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36

Pettersson, Per Olof. "Sampling-based Path Planning for an Autonomous Helicopter." Licentiate thesis, Linköping : Univ, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5270.

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37

Viana, Evelyn da Silva. "Estimação de velocidade de composições usando processamento de vídeo." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3416.

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Esta dissertação tem como objetivo estudar um método para estimar a velocidade de veículos ferroviários usando processamento de vídeo. O sistema proposto consiste na utilização de câmeras ao longo das vias férreas que permitam não só o monitoramento do tráfego ferroviário, mas cujo vídeo captado possa ser utilizado para a obtenção de estimativas para a velocidade instantânea dos trens que por ela trafegam. Tal sistema seria utilizado independentemente dos sistemas de controle já utilizados pela operadora do sistema ferroviário, permitindo que os controladores possam ter uma segunda análise no caso de falha da primeira, assim como um modelo que permita avaliar a velocidade instantânea do veículo ferroviário ao longo do percurso. Os algoritmos de rastreamento empregados para esse fim abordaram diferentes métodos. Confrontaram-se os resultados obtidos com os algoritmos propostos com os dados empíricos de forma a determinar aquele com melhor resposta dada as características do sistema. O algoritmo que apresentou os melhores resultados emprega um único bloco de referência para todos os quadros comparados. A métrica de similaridade responsável por determinar quais blocos são mais ou menos similares dentro do universo de busca estipulado é a soma de diferenças absolutas (SAD, Sum of Absolute Differences). O tempo de processamento requerido por cada um dos métodos de rastreamento estudados também foi considerado nas avaliações de resultados apresentadas. Uma comparação realizada entre as velocidades coletadas e aquelas informadas pelo sistema de controle mostraram que os resultados obtidos com o sistema atual, utilizando a sinalização apenas por circuito de via apresenta resultados pouco confiáveis com erros bastante significativos. Os resultados obtidos com o sistema proposto apresentaram erros menores quando comparados àqueles obtidos pelo sistema vigente, apresentando-se assim como uma solução viável e de baixo custo quando comparada às técnicas atualmente empregadas para a medida de velocidade de trens.
This dissertation aims to study a method of estimating the speed of railway vehicles using video processing. The proposed system uses cameras disposed alongside railways to monitor traffic as well as estimate train speeds. Such a system would allow the machinist to have a backup control system, regardless of the control systems already used by the operator of the rail system. In this dissertation, tracking algorithms with different methods are discussed. By comparing results obtained with the proposed algorithm and results from empirical data, it was possible to determine the one that best provided the desired results given the characteristics of the system. The algorithm which presented the best results was the one that employs a single block for all reference frames compared. The metric of similarity used for determining which blocks are most similar within the searched universe is the sum of absolute differences (SAD). The processing time required by each of the screening methods studied was also considered in assessing the results presented. A comparison between the rates collected and those informed by the control system showed that the results obtained with the current system, which only uses the signal track circuit, provides unreliable results with very significant errors. The results obtained with the proposed system had errors smaller than those obtained with the current system, suggesting the proposed system is viable and cost-effective compared to currently employed techniques.

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38

Gandrillon, Catherine. ""Albion's vital tree" : arbre, société et identité dans la peinture du portrait britannique de 1709 à 1792." Paris 7, 2003. http://www.theses.fr/2003PA070039.

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Constatant à la fois l'omniprésence de l'arbre dans la peinture de portrait britannique du dix-huitième siècle, et l'importance de l'arbre dans la culture et la société britanniques en général à la même époque, cette thèse pose la question du lien entre les deux phénomènes. Les portraits avec arbres sont replacés dans leur double contexte : la peinture de portrait et la place de l'arbre dans la société, l'économie, la culture et l'imaginaire. Puis, la thèse examine les diverses manières de représenter l'arbre. Les formules stéréotypées montrent que l'arbre est un élément clé d'une mise en scène culturelle, sociale et économique de l'individu et de la famille. On remarque ensuite que l'arbre est au cœur de plusieurs mythes constitutifs de l'imaginaire britannique. Ceux-ci ont un impact certain sur la peinture de portrait, dans le cadre d'une définition politique des modèles. Enfin, on s'intéresse à l'esthétique de l'arbre, indissociable du contexte scientifique et philosophique de l'époque. L'apparence de l'arbre dans le portrait dépend entièrement de la manière d'envisager l'identité du modèle et la nature profonde de la représentation picturale
Trees often appear in the backgrounds of British portraits from 1709 to 1792. At the same time, they come under unprecedented scrutiny in economic, social, patriotic, political, artistic and scientific discourse. This research explores the specificity of the representation of trees in British portraits of the eighteenth century by establishing a link between the texts and the images of the period. Trees are undeniably considered as key elements in a representational process that aims primarily at staging cultural, social and economic identity by stressing values shared by many members of the 'polite classes'. Moreover, trees are at the heart of several myths that contribute to a new definition of national and political identity and this too impacts on portraits. Ultimately, however, the representation and physical aspect of trees also depend on individual interest in the scientific, philosophical or artistic theories of the time, and on the way the artist or the sitter understands the depiction of identity through art and the very nature of a work of art

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39

Gaillard, Anne-Laure. "Identification de motifs au sein des structures biologiques arborescentes." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2011. http://tel.archives-ouvertes.fr/tel-00652227.

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Avec l'explosion de la quantité de données biologiques disponible, développer de nouvelles méthodes de traitements efficaces est une problématique majeure en bioinformatique. De nombreuses structures biologiques sont modélisées par des structures arborescentes telles que les structures secondaires d'ARN et l'architecture des plantes. Ces structures contiennent des motifs répétés au sein même de leur structure mais également d'une structure à l'autre. Nous proposons d'exploiter cette propriété fondamentale afin d'améliorer le stockage et le traitement de tels objets. En nous inspirant du principe de filtres sur les séquences, nous définissons dans cette thèse une méthode de filtrage sur les arborescences ordonnées, permettant de rechercher efficacement dans une base de données, un ensemble d'arborescences ordonnées proches d'une arborescence requête. La méthode se base sur un découpage de l'arborescence en graines et sur une recherche de graines communes entre les structures. Nous définissons et résolvons le problème de chaînage maximum sur des arborescences. Nous proposons dans le cas des structures secondaires d'ARN une définition de graines (l−d) centrées. Dans un second temps, en nous basant sur des techniques d'instanciations utilisées, par exemple, en infographie et sur la connaissance des propriétés de redondances au sein des structures biologiques, nous présentons une méthode de compression permettant de réduire l'espace mémoire nécessaire pour le stockage d'arborescences non-ordonnées. Après une détermination des redondances, nous utilisons une structure de données plus compacte pour représenter notamment l'architecture de la plante, celle-ci pouvant contenir des informations topologiques mais également géométriques.

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Baloni, Sonia Verfasser], Stefan [Akademischer Betreuer] Treue, Alexander [Akademischer Betreuer] Gail, Fred [Akademischer Betreuer] Wolf, Melanie [Akademischer Betreuer] Wilke, Tobias [Akademischer Betreuer] [Moser, and Hansjörg [Akademischer Betreuer] Scherberger. "Spatial, feature and temporal attentional mechanisms in visual motion processing / Sonia Baloni. Gutachter: Alexander Gail ; Fred Wolf ; Melanie Wilke ; Tobias Moser ; Hansjörg Scherberger. Betreuer: Stefan Treue." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044362081/34.

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Maazoun, Mickaël. "Permutons limites universels de permutations aléatoires à motifs exclus." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEN064.

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Les permutations à motifs exclus sont un thème important de la combinatoire énumérative et leur étude probabiliste un sujet récent en pleine expansion, notamment l'étude de la limite d'échelle, au sens des permutons, du diagramme d'une permutation aléatoire uniforme dont la taille tent vers l'infini dans une classe définie par exclusion de motifs. Le cas des permutations séparables a été étudié par Bassino, Bouvel, Féray, Gerin et Pierrot, qui ont démontré la convergence vers un objet aléatoire, permuton séparable Brownien. Nous fournissons une construction explicite à partir de processus stochastiques permettant d'étudier les propriétés fractales et de calculer certaines statistiques de cet objet. Nous étudions la classe d'universalité de ce permuton dans le cadre des classes admettant une spécification finie au sens de la décomposition par substitution. Pour nombre d'entre elles, sous une condition combinatoire simple, leur limite est une déformation à un paramètre du permuton séparable Brownien. Dans le cas des classes closes par substitution, nous considérons également des conditions suffisantes pour sortir de cette classe d'universalité, et introduisons la famille des permutons stables. Les cographes sont les graphes d'inversion des permutations séparables. Nous étudions par des méthodes similaires la convergence au sens des graphons du cographe étiqueté ou non-étiqueté uniforme, et montrons que le degré normalisé d'un sommet uniforme dans un cographe uniforme est asymptotiquement uniforme. Finalement, nous étudions les limites d'échelle et locale de la famille à motifs vinculaires exclus des permutations de Baxter. Cette classest en bijection avec de nombreux objets combinatoires remarquables, notamment les cartes bipolaires orientées. Notre résultat s'interprète en terme de la convergence de telles cartes au sens de la Peanosphere, complétant un résultat de Gwynne, Holden et Sun
Pattern-avoiding permutations are an important theme of enumerative combinatorics, and their study from a probabilistic point of view form a recently expanding subject, for instance by considering the scaling limit behavior, in the permuton sense, of the diagram of a large uniform permutation in a pattern-avoiding class. The case of separable permutations was studied by Bassino, Bouvel, Féray, Gerin and Pierrot, who showed convergence to a random object, the Brownian separable permuton. We provide an explicit construction through stochastic processes, allowing to study the fractal properties, and compute some statistics, of this object. We study the universality class of this permuton among classes admitting a finite specification in the sense of the so-called decomposition substitution. For many of them, under a simple combinatorial condition, their limit is a one-parameter deformation of the Brownian permuton. In the specific instance of substitution-closed classes, we also consider sufficient conditions to escape this universality class, and introduct the family of stable permutons. Cographs are the inversion graphs of separable permutations. Using similar methods, we investigate the scaling limit in the graphon sense of uniform labeled and unlabeled cographs. We also show that the normalized degree of a uniform vertex in a uniform cograph is asymptotically uniform. Finally, we study local and scaling limits of Baxter permutations, a class avoiding vincular patterns. This family is in bijection with many remarkable combinatorial objects, in particular bipolar oriented maps. Our result has interpretations in terms of the Peanosphere convergence of such maps, completing a result of Gwynne, Holden and Sun

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Pavret, de la Rochefordière Julie. "Narrations et témoinages dans True History of the Kelly Gang de Peter Carey, La main coupée de Blaise Cendrars et Absalom! Absalom! de William Faulkner." Toulouse 2, 2010. http://www.theses.fr/2010TOU20037.

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Le témoignage, initialement utilisé par la justice, constitue désormais un support à la création littéraire. Mais pourquoi témoigner ? Quelles sont les options que la littérature permet d’envisager ? True History of the Kelly Gang, La main coupée et Absalom ! Absalom ! rapportent individuellement trois formes de témoignages, à la fois différentes mais aussi complémentaires. Peter Carey appréhende ce type de récit à travers les lettres fictives que le bandit australien Ned Kelly aurait adressées à sa fille. La galerie de portraits rassemblés par Blaise Cendrars décrit l'expérience d'un soldat lors de la première Guerre Mondiale ; ses traits sont similaires avec ceux de l'auteur au point de semer la confusion entre l'identité des deux hommes. William Faulkner poursuit sa saga des familles du Sud : Quentin Comspon tente de reconstituer l'histoire de Thomas Sutpen à travers les nombreux récits de témoins pour découvrir la vérité, celle d'un homme mais surtout celle d'une société déchue. Ces auteurs ont cependant en commun de faire cohabiter la fiction et la réalité, deux notions contradictoires mais pourtant indissociables dans le cadre du témoignage. Chacun propose une narration originale pour « mettre en forme » ce type de récit appréhendé dans la perspective de Derrida. Ces trois propositions illustrent à premier abord la volonté de leurs auteurs respectifs de restituer la vérité : le but que poursuit le témoin. Mais chacune de ces tentatives représente également un défi pour l'écrivain. Le témoignage ne constitue plus seulement une quête pour ces personnages mais davantage un « tour de force » littéraire pour celui qui en est l'instigateur
Testimonies, initially used by judiciary institutions, have found their way into literary creation. Why do people testify? What are the options suggested by literature? True History of the Kelly Gang, La main coupée and Absalom! Absalom! present three types of testimony, which are both different and complementary. Peter Carey approaches this kind of narrative through the fictional letters that the Australian outlaw Ned Kelly is supposed to have written to his daughter. The gallery of portraits assembled by Blaise Cendrars describes a soldier's experience during WWI ; this soldier's features are so similar to the author's that the two men's identities appear to merge. William Faulkner continues his saga of southern families : Quentin Compson tries to recreate Thomas Sutpen's story by confronting the narratives of various witnesses in order to discover the truth about that man and above all about an extinct or fallen society. What is common to the three authors is the way in which fiction and ‘real life' - two contradictory yet inseparable notions - coexist in their narratives. Each of them offers an original narrative method (examined here from the perspective developed by Derrida) to “condition” this type of story. The three methods seem to be answers to the conundrum of how to produce a narrative that is ‘true' to reality. But in addition to being a quest where the characters are concerned, each of them is also a distinct challenge for the writer who needs to pull off a literary tour de force

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Andersson, Carl-Johan, and Stefan Olsson. "På jakt efter kunskap i Idrott och hälsa : En studie om idrottslärarutbildares syn på kunskap genom de tre vanligaste aktiviteterna i ämnet." Thesis, Kristianstad University, School of Teacher Education, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-6649.

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Syftet med studien är att undersöka vilka uppfattningar idrottslärarutbildare har om vad som är viktig kunskap för eleverna i grundskolan att utveckla genom de tre vanligaste aktiviteterna i ämnet Idrott och hälsa, enligt NU-03. De tre vanligaste aktiviteterna är bollaktiviteter, lekar och träning/motion. Sju intervjuer genomfördes med idrottslärarutbildare från fem olika lärosäten i det svenska utbildningssystemet. De analytiska verktygen som användes var Arnolds (1979;1985) teorier med bildning om, genom och i samt Carlgrens (2002) beskrivning av de fyra kunskapsformerna. Resultatet visade att de förtrogenhetskunskaper som enligt idrottslärarutbildarna var viktiga att utveckla i de tre aktiviteterna handlade om att kunna värdera olika aktiviteter i förhållande till varandra eller använda kunskapen individen har i en aktivitet i ett nytt sammanhang. Förtrogenhetskunskapen gick inte att utveckla i ämnet enligt en del av respondenterna. Fakta- och förståelsekunskaperna visade sig vara att få kunskap om regler och vad olika lekar och bollsporter går ut på för att kunna delta eller vara åskådare. Att känna till olika träningsformer och vad som är viktigt att tänka på i utförandet samt varför de är bra för hälsan var andra kunskaper som var viktiga att eleverna utvecklar. Bollaktiviteter och lekar visade sig även fungera som ett förmedlande redskap av viktiga kunskaper om kroppen, en förståelse för deltagandets positiva effekter för hälsan samt ett utökat socialt nätverk. Genom leken utvecklas kunskap om och förståelse för varför det är viktigt med sociala regler gentemot sin omgivning. Det var också viktigt att utveckla rörelsekompetensen, framförallt motoriska grundfärdigheter samt färdigheten att kunna utföra den rörelse som förknippas med respektive aktivitet, en bildning i rörelse.

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Janbrink, Sven. ""Detta och sommarnatten är jag satt att förvalta" : En stilistisk studie av tre romaner av Stig Claesson." Thesis, Högskolan Dalarna, Svenska språket, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:du-4827.

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I uppsatsen studeras stilen i Stig Claessons romaner Vem älskar Yngve Frej, På palmblad och rosor samt Henrietta ska du också glömma. Syftet är undersöka syntax, disposition och innehållsaspekter som motiv, symboler och tema och jämföra resultatet med tidigare forskning. I uppsatsen studeras också romanernas textbindning. Undersökningen visar att Claesson använder sig av repetition avseende både syntax, motiv och innehåll vilket skapar en väl sammanhållen, långsamt framskridande och rytmisk text med betydelseglidningar.

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Powell, Ellen Grace. "Scaling limits of critical systems in random geometry." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/270147.

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This thesis focusses on the properties of, and relationships between, several fundamental objects arising from critical physical models. In particular, we consider Schramm--Loewner evolutions, the Gaussian free field, Liouville quantum gravity and the Brownian continuum random tree. We begin by considering branching diffusions in a bounded domain $D\subset$ $R^{d}$, in which particles are killed upon hitting the boundary $\partial D$. It is known that such a system displays a phase transition in the branching rate: if it exceeds a critical value, the population will no longer become extinct almost surely. We prove that at criticality, under mild assumptions on the branching mechanism and diffusion, the genealogical tree associated with the process will converge to the Brownian CRT. Next, we move on to study Gaussian multiplicative chaos. This is the rigorous framework that allows one to make sense of random measures built from rough Gaussian fields, and again there is a parameter associated with the model in which a phase transition occurs. We prove a uniqueness and convergence result for approximations to these measures at criticality. From this point onwards we restrict our attention to two-dimensional models. First, we give an alternative, ``non-Gaussian" construction of Liouville quantum gravity (a special case of Gaussian multiplicative chaos associated with the 2-dimensional Gaussian free field), that is motivated by the theory of multiplicative cascades. We prove that the Liouville (GMC) measures associated with the Gaussian free field can be approximated using certain sequences of ``local sets" of the field. This is a particularly natural construction as it is both local and conformally invariant. It includes the case of nested CLE$_{4}$, when it is coupled with the GFF as its set of ``level lines". Finally, we consider this level line coupling more closely, now when it is between SLE$_{4}$ and the GFF. We prove that level lines can be defined for the GFF with a wide range of boundary conditions, and are given by SLE$_{4}$-type curves. As a consequence, we extend the definition of SLE$_{4}(\rho)$ to the case of a continuum of force points.

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Kutil, Brandi Lynn. "The evolution of LOL, the secondary metabolite gene cluster for insecticidal loline alkaloids in fungal endophytes of grasses." Thesis, [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1122.

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Younis, Maya. "Skogens vänner och värden -En motivstudie av djur och natur i tre bilderböcker." Thesis, Örebro universitet, Institutionen för humaniora, utbildnings- och samhällsvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-92507.

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Denna motivstudie analyserar vilka teman och motiv som finns i tre bilderböcker: Puttes äventyr i blåbärsskogen (1901) av Elsa Beskow, Bus och Frö på varsin ö (2012) av Maria Nilsson Thore och Lille Lustig och skogens vänner (2015) av Inger Kvillner och Eva Kvillner. Syftet med analysen är att undersöka hur naturskildring och gestaltning av djur framställs i tre utvalda bilderböcker för barn, vilka motiv som finns i dessa böcker samt samspelet mellan bild och text. Studien utgår från en kvalitativ metod och använder sig av Nikolajevas och Ulla Rehdins bilderbokenskategorier. Analysen visar hur bilderböckerna använder sig av följande tema och motiv: natur och djur, vänskap, utanförskap och olikhet. Resultatet visar att bilderböckerna har skapats för ett didaktiskt syfte, där ansvaret placeras på den individuella snarare än på samhälleliga nivån. I min analys ser jag att en stor del av bilderna utgår från textens beskrivningar, och vissa detaljer och färgglada bilder har anpassats till yngre barn.

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Willocks, Remy M. "Masculinity on Every Channel: The Development and Demonstration of American Masculinity of the Postwar Period via 1960s Television." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1574024599256381.

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49

Zoumboulaki, Sophia. "L' Arbre de Jessé et la représentation des philosophes grecs et autres sages païens dans la peinture murale byzantine et post-byzantine." Thesis, Paris 1, 2015. http://www.theses.fr/2015PA010516.

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L'Arbre de Jessé est une image particulièrement complexe qui a connu plusieurs variantes iconographiques. Le type christologique complexe est une création byzantine du sujet. Ce type est constitué de plusieurs éléments iconographiques, comme des scènes prophétiques, des figures des ancêtres et des prophètes. A ce noyau iconographique s 'ajouteront à partir de la fin du XIIIe siècle et le début du XIVe siècle les figures des sages et philosophes païens. Dans la présente étude nous examinons l'iconographie de ce type et nous essayons de comprendre, à travers les images et les inscriptions écrites sur les rouleaux des sages païens, cette association afin de retracer ses étapes d'évolution principales dans la peinture murale byzantine et post-byzantine
The Tree of Jesse is a particularly complicated pictorial theme, which can be found in many different versions. The complex christological type is a purely Byzantine creation. Towards the end of 13th and early 14th century, figures of sages and philosophers of the Greek antiquity are added to this type, which already contains many iconographic elements such as prophetic and evangelical scene and independent figures of prophets and ancestors of Christ. In this study we examine the compositions and the texts of the inscriptions written on the pagan's scrolls this iconographic combination in order to trace its key evolutional stages in Byzantine and post-Byzantine mural painting

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Neto, Domingos Soares. "Filtros para a busca e extração de padrões aproximados em cadeias biológicas." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-19102009-002745/.

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Esta dissertação de mestrado aborda formulações computacionais e algoritmos para a busca e extração de padrões em cadeias biológicas. Em particular, o presente texto concentra-se nos dois problemas a seguir, considerando-os sob as distâncias de Hamming e Levenshtein: a) como determinar os locais nos quais um dado padrão ocorre de modo aproximado em uma cadeia fornecida; b) como extrair padrões que ocorram de modo aproximado em um número significativo de cadeias de um conjunto fornecido. O primeiro problema, para o qual já existem diversos algoritmos polinomiais, tem recebido muita atenção desde a década de 60, e ganhou novos ares com o advento da biologia computacional, nos idos dos anos 80, e com a popularização da Internet e seus mecanismos de busca: ambos os fenômenos trouxeram novos obstáculos a serem superados, em razão do grande volume de dados e das bastante justas restrições de tempo inerentes a essas aplicações. O segundo problema, de surgimento um pouco mais recente, é intrinsicamente desafiador, em razão de sua complexidade computacional, do tamanho das entradas tratadas nas aplicações mais comuns e de sua dificuldade de aproximação. Também é de chamar a atenção o seu grande potencial de aplicação. Neste trabalho são apresentadas formulações adequadas dos problemas abordados, assim como algoritmos e estruturas de dados essenciais ao seu estudo. Em especial, estudamos a extremamente versátil árvore dos sufixos, assim como uma de suas generalizações e sua estrutura irmã: o vetor dos sufixos. Grande parte do texto é dedicada aos filtros baseados em q-gramas para a busca aproximada de padrões e algumas de suas mais recentes variações. Estão cobertos os algoritmos bit-paralelos de Myers e Baeza-Yates-Gonnet para a busca de padrões; os algoritmos de Sagot para a extração de padrões; os algoritmos de filtragem de Ukkonen, Jokinen-Ukkonen, Burkhardt-Kärkkäinen, entre outros.
This thesis deals with computational formulations and algorithms for the extraction and search of patterns from biological strings. In particular, the present text focuses on the following problems, both considered under Hamming and Levenshtein distances: 1. How to find the positions where a given pattern approximatelly occurs in a given string; 2. How to extract patterns which approximatelly occurs in a certain number of strings from a given set. The first problem, for which there are many polinomial time algorithms, has been receiving a lot of attention since the 60s and entered a new era of discoveries with the advent of computational biology, in the 80s, and the widespread of the Internet and its search engines: both events brought new challenges to be faced by virtue of the large volume of data usually held by such applications and its time constraints. The second problem, much younger, is very challenging due to its computational complexity, approximation hardness and the size of the input data usually held by the most common applications. This problem is also very interesting due to its potential of application. In this work we show computational formulations, algorithms and data structures for those problems. We cover the bit-parallel algorithms of Myers, Baeza-Yates-Gonnet and the Sagots algorithms for patterns extraction. We also cover here the oustanding versatile suffix tree, its generalised version, and a similar data structure: the suffix array. A significant part of the present work focuses on q-gram based filters designed to solve the approximate pattern search problem. More precisely, we cover the filter algorithms of Ukkonen, Jokinen-Ukkonen and Burkhardt-Kärkkäinen, among others.

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Dissertations / Theses on the topic 'Tree motion'

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