Tesi sul tema "Shape"
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1
SOUZA, MARCIO ALBUQUERQUE DE. "ARBITRARILY SHAPED OBJECT CODING USING SHAPE-ADAPTATIVE DWT AND SHAPE-ADAPTATIVE SPIHT". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2001. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=1748@1.
Testo completoAbstract (sommario):
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORCodificação de objetos de forma arbitrária extraídos de imagens regulares é um dos assuntos de maior desafio nos mais recentes padrões de codificação de vídeo (MPEG-4). Neste estudo, é proposta uma nova estratégia de codificação de objetos envolvendo maior eficiência na decomposição e quantização de sub-bandas. A técnica de transformação proposta envolve Transformada Wavelet Discreta (DWT) e a de quantização é baseada no algoritmo de Partição de Conjuntos em Árvores Hierárquicas (SPIHT).
Coding of arbitrarily shaped objects extracted from regular images is one of the most challenging issues on the latest video coding standards (MPEG-4). In this work, a new object coding strategy is proposed, involving greater efficiency on subband splitting and quantization. The proposed transform technique involves Discrete Wavelet Transform (DWT) and the proposed quantization technique is based on the Set Partitioning in Hierarchical Trees (SPIHT) algorithm.
La codificación de objetos de forma arbitraria extraídos de imágenes regulares es uno de los asuntos de mayor desafío en los más recientes padrones de codificación de video (MPEG-4). En este estudio, se propone una nueva estrategia de codificación de objetos con mayor eficiencia en la descomposición y cuantización de subbandas. La técnica de transformación propuesta incluye Transformada Wavelet Discreta (DWT) y la de cuantización tiene como base el algoritmo de Partición de Conjuntos en Árboles Jerárquicas (SPIHT).
2
Kelly, Brian L. "Beam shape control using shape memory alloys". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA358806.
Testo completoAbstract (sommario):
Thesis (M.S. in Astronautical Engineering) Naval Postgraduate School, December 1998."December 1998." Thesis advisor(s): Brij N. Agrawal, Gangbing Song. Includes bibliographical references (p. 55). Also available online.
3
Su, Z. "Statistical shape modelling : automatic shape model building". Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1213097/.
Testo completoAbstract (sommario):
Statistical Shape Models (SSM) have wide applications in image segmentation, surface registration and morphometry. This thesis deals with an important issue in SSM, which is establishing correspondence between a set of shape surfaces on either 2D or 3D. Current methods involve either manual annotation of the data (current ‘gold standard’); or establishing correspondences by using segmentation or registration algorithms; or using an information technique, Minimum Description Length (MDL), as an objective function that measures the utility of a model (the state-of-the-art). This thesis presents in principle another framework for establishing correspondences completely automatically by treating it as a learning process. Shannon theory is used extensively to develop an objective function, which measures the performance of a model along each eigenvector direction, and a proper weighting is automatically calculated for each energy component. Correspondence finding can then be treated as optimizing the objective function. An efficient optimization method is also incorporated by deriving the gradient of the cost function. Experimental results on various data are presented on both 2D and 3D. In the end, a quantitative evaluation between the proposed algorithm and MDL shows that the proposed model has better Generalization Ability, Specificity and similar Compactness. It also shows a good potential ability to solve the so-called “Pile Up” problem that exists in MDL. In terms of application, I used the proposed algorithm to help build a facial contour classifier. First, correspondence points across facial contours are found automatically and classifiers are trained by using the correspondence points found by the MDL, proposed method and direct human observer. These classification schemes are then used to perform gender prediction on facial contours. The final conclusion for the experiments is that MEM found correspondence points built classification scheme conveys a relatively more accurate gender prediction result. Although, we have explored the potential of our proposed method to some extent, this is not the end of the research for this topic. The future work is also clearly stated which includes more validations on various 3D datasets; discrimination analysis between normal and abnormal subjects could be the direct application for the proposed algorithm, extension to model-building using appearance information, etc.
4
Yalim, Keles Hacer. "Part Embedding For Shape Grammars". Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612231/index.pdf.
Testo completoAbstract (sommario):
Computational modeling of part relations of shapes is a challenging problem that has been addressed by many researchers since sixties. The most important source of the difficulty is the continuous nature of shapes, which makes the expression of shape very difficult in terms of discrete parts. When discrete parts are combined, they fuse and yield new parts, i.e. parts emerge. There is a number of methods that support emergent part detection. However all of these methods are based on strong assumptions in terms of what constitute a part. There is a need for a generic solution that treats a shape independently of any restriction resulting from
analytical, geometrical, or logical abstractions. To this end, we have developed two novel strategies, which can be used both separately and jointly. Both strategies are relatable to the algebraic formalization of shape grammars (by Stiny). In the course of this thesis work, we have introduced a novel data structure called Over-Complete Graph to address the problem of part embedding in the existence of discrete registration marksand we have developed a novel and robust method for the automatic selection of registration marks. Both developments are certainly useful for other visual problems. On the application side, we have tested our techniques on puzzling Seljuk patterns (from Kayseri) to demonstrate how the developed techniques give way to computational creativity. Apart from the techniques we have developed, the most important contribution of our work is that shapes are treated as perceived wholes rather than composed, as compellingly demonstrated by Seljuk pattern experiments.
5
Jowers, Iestyn. "Computation with curved shapes : towards freeform shape generation in design". Thesis, Open University, 2007. http://oro.open.ac.uk/43671/.
Testo completoAbstract (sommario):
Shape computations are a formal representation that specify particular aspects of the design process with reference to form. They are defined according to shape grammars, where manipulations of pictorial representations of designs are formalised by shapes and rules applied to those shapes. They have frequently been applied in architecture in order to formalise the stylistic properties of a given corpus of designs, and also to generate new designs within those styles. However, applications in more general design fields have been limited. This is largely due to the initial definitions of the shape grammar formalism which are restricted to rectilinear shapes composed of lines, planes or solids. In architecture such shapes are common but in many design fields, for example industrial design, shapes of a more freeform nature are prevalent. Accordingly, the research described in this thesis is concerned with extending the applicability of the shape grammar formalism such that it enables computation with freeform shapes. Shape computations utilise rules in order to manipulate subshapes of a design within formal algebras. These algebras are specified according to embedding properties and have previously been defined for rectilinear shapes. In this thesis the embedding properties of freeform shapes are explored and the algebras are extended in order to formalise computations with such shapes. Based on these algebras, shape operations are specified and algorithms are introduced that enable the application of rules to shapes composed of freeform B´ezier curves. Implementation of the algorithms enables the application of shape grammars to shapes of a more freeform nature than was previously possible. Within this thesis shape grammar implementations are introduced in order to explore both theoretical issues that arise when considering computation with freeform shapes and practical issues concerning the application of shape computation as a model for design and as a mode for generating freeform shapes.
6
黃美香 e Mee-heung Cecilia Wong. "Shape analysis". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31211999.
Testo completo
7
Aktas, Mehmet Ali. "Shape descriptors". Thesis, University of Exeter, 2012. http://hdl.handle.net/10871/9663.
Testo completoAbstract (sommario):
Every day we recognize a numerous objects and human brain can recognize objects under many conditions. The way in which humans are able to identify an object is remarkably fast even in different size, colours or other factors. Computers or robots need computational tools to identify objects. Shape descriptors are one of the tools commonly used in image processing applications. Shape descriptors are regarded as mathematical functions employed for investigating image shape information. Various shape descriptors have been studied in the literature. The aim of this thesis is to develop new shape descriptors which provides a reasonable alternative to the existing methods or modified to improve them. Generally speaking shape descriptors can be categorized into various taxonomies based on the information they use to compute their measures. However, some descriptors may use a combination of boundary and interior points to compute their measures. A new shape descriptor, which uses both region and contour information, called centeredness measure has been defined. A new alternative ellipticity measure and sensitive family ellipticity measures are introduced. Lastly familiy of ellipticity measures, which can distinguish between ellipses whose ratio between the length of the major and minor axis differs, have been presented. These measures can be combined and applied in different image processing applications such as image retrieval and classification. This simple basis is demonstrated through several examples.
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Baumgardner, Thomas A. "Shape Matters". ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1903.
Testo completoAbstract (sommario):
An analysis of the production of the University of New Orleans thesis film, Shape Matters, a period film, written and directed by Thomas Baumgardner. The film is concerned with the practice of Phrenology and follows a nervous preacher who becomes entangled in the bizarre "science" and a local murder. This paper describes the director's experiences and details the challenges encountered, and lessons learned, from attempting to bring the project to fruition.
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Wong, Mee-heung Cecilia. "Shape analysis /". [Hong Kong : University of Hong Kong], 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13637642.
Testo completo
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Larsen, Shane H. "Recognizing Parametric Geometry from Topology Optimization Results". BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2072.
Testo completoAbstract (sommario):
Topology Optimization has been proven to be a useful tool in discovering non-intuitive optimal designs subject to certain design constraints. The results of Topology Optimization are either represented as a tessellation object composed of thousands of triangular surfaces, or as a point cloud. In either case, the results of Topology Optimization are not suited for use in subsequent steps of the design process which require 3D parametric CAD (Computer Aided Design) models. Converting Topology Optimization results into parametric CAD geometry by hand is an extremely tedious and time consuming process which is highly subjective. This thesis presents a shape recognition algorithm that uses a feature by feature CAD-centric approach to convert Topology Optimization results into parametric CAD geometry. This is accomplished by fitting 2D cross section geometry to various parts of a given feature through the use of Shape Templates and then constructing 3D surfaces through the set of 2D cross sections. This algorithm aids in measuring the geometric approximation error of the generated geometry as compared to the optimal model, and standardizes the process through automation techniques. It also aids the designer / engineer in managing the direct tradeoff between closeness of geometric approximation (measured by volumetric comparison) and model complexity (measured by the number of parameters required to represent the geometry).
11
Lin, Cong. "Digital shape classification using local and global shape descriptors". Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2492875.
Testo completo
12
Erdem, Ibrahim Aykut. "Category Knowledge, Skeleton-based Shape Matching And Shape Classification". Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12610118/index.pdf.
Testo completoAbstract (sommario):
Skeletal shape representations, in spite of their structural instabilities, have proven themselves as effective representation schemes for recognition and classification of visual shapes. They capture part structure in a compact and natural way and provide insensitivity to visual transformations such as occlusion and articulation of parts.
In this thesis, we explore the potential use of disconnected skeleton representation for shape recognition and shape classification. Specifically, we first investigate the importance of contextual information in recognition where we extend the previously proposed disconnected skeleton based shape matching methods in different ways by incorporating category knowledge into matching process. Unlike the view in syntactic matching of shapes, our interpretation differentiates the semantic roles of the shapes in comparison in a way that a query shape is being matched with a database shape whose category is known a priori. The presence of context, i.e. the knowledge about the category of the database shape, influences the similarity computations, and helps us to obtain better matching performance. Next, we build upon our category-influenced matching framework in which both shapes and shape categories are represented with depth-1 skeletal trees, and develop a similarity-based shape classification method where the category trees formed for each shape category provide a reference set for learning the relationships between categories. As our classification method takes into account both within-category and between-category information, we attain high classification performance. Moreover, using the suggested classification scheme in a retrieval task improves both the efficiency and accuracy of matching by eliminating unrelated comparisons.
13
Alkan, Sencer. "Fuzzy evolutionary shape and shape recognition for log modelling". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq23858.pdf.
Testo completo
14
Tykac, Michal. "Protein shape description and its application to shape comparison". Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/284410.
Testo completoAbstract (sommario):
There are currently over 138, 000 known macromolecular structures deposited in the wwPDB (Worldwide Protein Data Bank) database. While all the macromolecular structure files contain information about a particular structure, the collection of these files also allows combining the macromolecular structures to obtain statistical information about macromolecules in general. This fact has been the basis for many structural biology methods including the molecular replacement method used in X-ray crystallography or homologous structure restraints in the refinement methods. With the success of methods based on prior information, it is feasible that novel methods could be developed and current methods improved using further prior information; more specifically, by using the structure density-map shape similarity instead of sequence or model similarity. Therefore, this project introduces a mathematical framework for computing three different measures of macromolecular three-dimensional shape similarity and demonstrates how these descriptors can be applied in symmetry detection and protein-domain clustering. The ability to detect cyclic (C), dihedral (D), tetrahedral (T), octahedral (O) and icosahedral (I) symmetry groups as well as computing all associated symmetry elements has direct applications in map averaging and reducing the storage requirements by storing only the asymmetric information. Moreover, by having the capacity to find structures with similar shape, it was possible to reduce the size of the BALBES protein domain database by more than 18.7% and thus achieve proportional speed-up in the searching parts of its applications. Finally, the development of the method described in this project has many possible applications throughout structural biology. The method could, for example, facilitate matching and fitting of protein domains into the density maps produced by the electron-microscopy techniques, or it could allow for molecular-replacement candidate search using shape instead of sequence similarity. To allow for the development of any further applications, software for applying the methods described here is also presented and released for the community.
15
Li, Zongcheng. "Conceptual design of shapes by reusing existing heterogeneous shape data through a multi-layered shape description model and for VR applications". Thesis, Paris, ENSAM, 2015. http://www.theses.fr/2015ENAM0025/document.
Testo completoAbstract (sommario):
Les récentes avancées en matière de systèmes d'acquisition et de modélisation ont permis la mise à disposition d'une très grande quantité de données numériques (e.g. images, vidéos, modèles 3D) dans différents domaines d'application. En particulier, la création d'Environnements Virtuels (EVs) nécessite l'exploitation de données nu-mériques pour permettre des simulations et des effets proches de la réalité. Malgré ces avancées, la conception d'EVs dédiés à certaines applications requiert encore de nombreuses et parfois laborieuses étapes de modélisation et de traitement qui impliquent plusieurs experts (e.g. experts du domaine de l'application, experts en modélisation 3D et programmeur d'environnements virtuels, designers et experts communication/marketing). En fonction de l'application visée, le nombre et le profil des experts impliqués peuvent varier. Les limitations et difficultés d'au-jourd'hui sont principalement dues au fait qu'il n'existe aucune relation forte entre les experts du domaine qui ont des besoins, les experts du numérique ainsi que les outils et les modèles qui prennent part au processus de déve-loppement de l'EV. En fait, les outils existants focalisent sur des définitions souvent très détaillées des formes et ne sont pas capables de supporter les processus de créativité et d'innovation pourtant garants du succès d'un pro-duit ou d'une application. De plus, la grande quantité de données numériques aujourd'hui accessible n'est pas réellement exploitée. Clairement, les idées innovantes viennent souvent de la combinaison d'éléments et les don-nées numériques disponibles pourraient être mieux utilisées. Aussi, l'existence de nouveaux outils permettant la réutilisation et la combinaison de ces données serait d'une grande aide lors de la phase de conception conceptuelle de formes et d'EVs. Pour répondre à ces besoins, cette thèse propose une nouvelle approche et un nouvel outil pour la conception conceptuelle d'EVs exploitant au maximum des ressources existantes, en les intégrant et en les combinant tout en conservant leurs propriétés sémantiques. C'est ainsi que le Modèle de Description Générique de Formes (MDGF) est introduit. Ce modèle permet la combinaison de données multimodales (e.g. images et maillages 3D) selon trois niveaux : Conceptuel, Intermédiaire et Données. Le niveau Conceptuel exprime quelles sont les différentes parties de la forme ainsi que la façon dont elles sont combinées. Chaque partie est définie par un Elément qui peut être soit un Composant soit un Groupe de Composants lorsque ceux-ci possèdent des carac-téristiques communes (e.g. comportement, sens). Les Eléments sont liés par des Relations définies au niveau Con-ceptuel là où les experts du domaine interagissent. Chaque Composant est ensuite décrit au niveau Données par sa Géométrie, sa Structure et ses informations Sémantiques potentiellement attachées. Dans l'approche proposée, un Composant est une partie d'image ou une partie d'un maillage triangulaire 3D. Quatre Relations sont proposées (fusion, assemblage, shaping et localisation) et décomposées en un ensemble de Contraintes qui contrôlent la po-sition relative, l'orientation et le facteur d'échelle des Composants au sein de la scène graphique. Les Contraintes sont stockées au niveau Intermédiaire et agissent sur des Entités Clés (e.g. points, des lignes) attachées à la Géo-métrie ou à la Structure des Composants. Toutes ces contraintes sont résolues en minimisant une fonction énergie basée sur des grandeurs physiques. Les concepts du MDGF ont été implémentés et intégrés au sein d'un outil de design conceptuel développé par l'auteur. Différents exemples illustrent le potentiel de l'approche appliquée à différents domaines d'applicationDue to the great advances in acquisition devices and modeling tools, a huge amount of digital data (e.g. images, videos, 3D models) is becoming now available in various application domains. In particular, virtual envi-ronments make use of those digital data allowing more attractive and more effectual communication and simula-tion of real or not (yet) existing environments and objects. Despite those innovations, the design of application-oriented virtual environment still results from a long and tedious iterative modeling and modification process that involves several actors (e.g. experts of the domain, 3D modelers and VR programmers, designers or communica-tions/marketing experts). Depending of the targeted application, the number and the profiles of the involved actors may change. Today's limitations and difficulties are mainly due to the fact there exists no strong relationships between the expert of the domain with creative ideas, the digitally skilled actors, the tools and the shape models taking part to the virtual environment development process. Actually, existing tools mainly focus on the detailed geometric definition of the shapes and are not suitable to effectively support creativity and innovation, which are considered as key elements for successful products and applications. In addition, the huge amount of available digital data is not fully exploited. Clearly, those data could be used as a source of inspiration for new solutions, being innovative ideas frequently coming from the (unforeseen) combination of existing elements. Therefore, the availability of software tools allowing the re-use and combination of such digital data would be an effective support for the conceptual design phase of both single shapes and VR environments. To answer those needs, this thesis proposes a new approach and system for the conceptual design of VRs and associated digital assets by taking existing shape resources, integrating and combining them together while keeping their semantic meanings. To support this, a Generic Shape Description Model (GSDM) is introduced. This model allows the combination of multimodal data (e.g. images and 3D meshes) according to three levels: conceptual, intermediate and data levels. The conceptual level expresses what the different parts of a shape are, and how they are combined together. Each part of a shape is defined by an Element that can either be a Component or a Group of Components when they share common characteristics (e.g. behavior, meaning). Elements are linked with Relations defined at the Concep-tual level where the experts in the domain are acting and exchanging. Each Component is then further described at the data level with its associated Geometry, Structure and potentially attached Semantics. In the proposed ap-proach, a Component is a part of an image or a part of a 3D mesh. Four types of Relation are proposed (merging, assembly, shaping and location) and decomposed in a set of Constraints which control the relative position, orien-tation and scaling of the Components within the 3D viewer. Constraints are stored at the intermediate level and are acting on Key Entities (such as points, a lines, etc.) laying on the Geometry or Structure of the Components. All these constraints are finally solved while minimizing an additional physically-based energy function. At the end, most of the concepts of GSDM have been implemented and integrated into a user-oriented conceptual design tool totally developed by the author. Different examples have been created using this tool demonstrating the potential of the approach proposed in this document
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Walls-Bruck, Marcus. "Shape adaptive self-fixing structures using shape memory alloy actuation". Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556738.
Testo completoAbstract (sommario):
Shape changing or morphing structures enable optimisation of structural configuration to suit current operating conditions. Conventional techniques for achieving shape change often result in weight and complexity penalties, which may outweigh the potential benefits of greater shape changing ability. The research presented in this thesis focuses on the use of shape memory materials to achieve a reversible change in shape of an innovative compliant composite structure, which may enable shape change without the drawbacks of conventional shape changing techniques. An initial concept was evaluated using a glass fibre reinforced shape memory polymer which was heated and deformed locally to fix the actuated shape. It was found that a large change in shape can be achieved. However, due to the high shear strain between the fibres during large deformations, fibre/matrix debonding occurred and propagated with repeated cycling. An alternative topology, consisting of a shape memory polymer reinforced with comparatively large diameter precured CFRP composite rods, was proposed and successfully demonstrated to reduce matrix shear strains, thereby reducing damage during deformation. The increased reinforcement size also improved load carrying ability when the shape memory polymer was in its low stiffness state. Initial testing of a rod reinforced composite beam with a low stiffness elastomer matrix indicated that shape memory alloy actuators wound helically around the composite beam could be effectively used to provide Significant rotational actuation. A constitutive model of the shape memory alloy thermo-mechanical behaviour was compared to the experimental findings for different configurations of shape memory alloy winding around the composite beam. A composite beam with a shape memory polymer matrix was found capable of 'locking' and 'releasing' mechanically introduced rotational shape change. The composite beam topology used initially consisted of circular rods and relied upon an adhesive for torsional rod restraint within the end alignment fittings, often resulting in failure of the adhesive and large non- returnable rotations at the temperatures required for softening of the shape memory polymer matrix. Rectangular cross section rods were used to enable the end fittings to mechanically restrain the rods in torsion. The rectangular rod topology also gave a large increase in bending stiffness compared to circular rods, with both topologies having similar torsional rigidities. A key aspect of the actuator performance was found to be the rate at which the shape memory materials could be activated by heating or cooling. This was found to be a particular problem for the shape memory polymer. To increase the rate of heating for the composite beam with a shape memory polymer matrix, efforts were made to incorporate carbon nanotubes to improve the thermal response of the material. However, only a modest change in thermal properties was achieved, combined with some undesirable detrimental effects on mechanical and therrno- mechanical properties. Further work is needed to optimise this combination. A final composite beam demonstrator combining both helically wound shape memory alloy wires for actuation and a shape memory polymer matrix for shape fixing was constructed. The shape memory polymer matrix was heated using an embedded heating element. By activating the shape memory alloy actuators when the shape memory polymer matrix was in its soft state, a rotation was achieved. Cooling the shape memory polymer matrix before the shape memory alloy actuators fixed the rotated, which was returned upon reheating the shape memory polymer matrix.
17
Rodriguez, Garcia Alberto. "Shape For Contact". Thesis, Carnegie Mellon University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3575524.
Testo completoAbstract (sommario):
Given a desired function for an effector, what is its appropriate shape? This thesis addresses the problem of designing the shape of a rigid end effector to perform a given manipulation task. It presents three main contributions: First, it describes the contact kinematics of an effector as the product of both its shape and its motion, and assumes a fixed motion model to explore the role of shape in satisfying a certain manipulation task. Second, it formulates that manipulation task as a set of constraints on the geometry of contact between the effector and the world. Third, it develops tools to transform those contact constraints into an effector shape for general 1-DOF planar mechanisms and general 1-DOF spatial mechanisms, and discusses the generalization to mechanisms with more than one degree of freedom.
We describe the case studies of designing grippers with invariant grasp geometry, grippers with improved grasp stability, and grippers with extended grasp versatility. We further showcase the techniques with the design of the fingers of the MLab hand, a three-fingered gripper actuated with a single motor, capable of exerting any combination of geometrically correct enveloping or fingertip grasps of spherical, cylindrical, and prismatic objects of varying size.
18
Kim, Jeong-Gyoo. "Probabilistic shape models :". Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433472.
Testo completo
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West, G. "Automated shape anthropometry". Thesis, Loughborough University, 1993. https://dspace.lboro.ac.uk/2134/7430.
Testo completoAbstract (sommario):
In medicine, ergonomics, the clothing Industry and many other areas such as the design of 'g' suits for military aeroplane pilots and protective clothing for chemical warfare, there is a requirement for the accurate 3-D measurement of the size and shape of the human form. To meet this need a novel whole body scanner has been designed which is capable of measuring both the size and shape of people in a non invasive socially acceptable manner. The scanner uses structured light and an array of television cameras to view free standing subjects while they are being rotated on an electrically driven turntable. The accuracy and repeatability of the scanner is as good as trained anthropometrists using traditional manual methods. A computer program has been written which uses a cubic spline interpolation method to edit and interrogate the data from the scanner and arrange it in a shape matrix form. This is a new way of arranging the data which allows for the 3-D average of several bodies to be obtained and also for the comparison of one body with another. A technique which is essential if 3-D survey work is to be undertaken. Using master files which contain information from a data base of previously scanned people and eight circumferential measurements it is possible to re-create body forms of any size but which correspond to the average shape for that size. The re-creation of body shapes from eight circumferences is accurate enough for the manufacture of all but the most close fitting garments but may be more useful in the future as a replacement for somatotyping (physique classification). It is perfectly possible to manipulate the eight circumferences to create body torsos of almost any shape. Conversely a torso of almost any shape could be defined by eight two digit numbers.
20
Sroufe, Paul. "E‐Shape Analysis". Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc12201/.
Testo completoAbstract (sommario):
The motivation of this work is to understand E-shape analysis and how it can be applied to various classification tasks. It has a powerful feature to not only look at what information is contained, but rather how that information looks. This new technique gives E-shape analysis the ability to be language independent and to some extent size independent. In this thesis, I present a new mechanism to characterize an email without using content or context called E-shape analysis for email. I explore the applications of the email shape by carrying out a case study; botnet detection and two possible applications: spam filtering and social-context based finger printing. The second part of this thesis takes what I apply E-shape analysis to activity recognition of humans. Using the Android platform and a T-Mobile G1 phone I collect data from the triaxial accelerometer and use it to classify the motion behavior of a subject.
21
Vittert, Liberty. "Facial shape analysis". Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6669/.
Testo completoAbstract (sommario):
Stereophotogrammetric imaging systems produce representations of surfaces (two-dimensional manifolds in three-dimensional space) through triangulations of a large number of estimated surface points. Traditional forms of analysis of these surfaces are based on point locations (manually marked anatomical landmarks) as described in Chapter 1. An advanced application of these types of landmarks will be thoroughly examined in Chapter 2 through the concept of Ghost Imaging. The results of this chapter necessitated a reliability study of stereophotogrammetric imaging systems which is discussed in Chapter 3. Given the results of the reliability study, an investigation info new definitions of landmarks and facial shape description is undertaken in Chapter 4. A much richer representation is expressed by the curves which track the ridges and valleys of the dense surface and by the relatively smooth surface patches which lie between these curves. New automatic methods for identifying anatomical curves and the resulting full surface representation, based on shape index, curvature, smoothing techniques, warping, and bending energy, are described. Chapter 5 discussed new and extended tools of analysis that are necessary for this richer representation of facial shape. These methods will be applied in Chapter 6 to different shape objects, including the human face, mussel shells, and computational imaging comparisons. Issues of sexual dimorphism (differences in shapes between males and females), change in shape with age, as well as pre- and post-facial surgical intervention will be explored. These comparisons will be made using new methodological tools developed specifically for the new curve and surface identification method. In particular, the assessment of facial asymmetry and the questions involved in comparing facial shapes in general, at both the individual and the group level, will also be considered. In Chapter 7, Bayesian methods are explored to determine further ways in which to understand and compare human facial features. In summary, this thesis shows a novel method of curve and full facial mesh identification that is used, successfully, in pilot case studies of multiple types of surfaces. It then shows a novel proof of principle for using Bayesian methods to create a fully automatic process in facial shape characterisation. In order to view this thesis in full, please view in Adobe Reader.
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Varón, González Ceferino. "Shape and phylogeny". Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/shape-and-phylogeny(f432d494-9755-41f9-b067-431023ad3248).html.
Testo completoAbstract (sommario):
Geometric morphometrics, the science about the study of shape, has developed much in the last twenty years. In this thesis I first study the reliability of the phylogenies built using geometric morphometrics. The effect of different evolutionary models, branch-length combinations, dimensionality and degrees of integration is explored using computer simulations. Unfortunately in the most common situations (presence of stabilizing selection, short distance between internal nodes and presence of integration) the reliability of the phylogenies is very low. Different empirical studies are analysed to estimate the degree of evolutionary integration usually found in nature. This gives an idea about how powerful the effect of integration is over the reliability of the phylogenies in empirical studies. Evolutionary integration is studied looking at the decrease of variance in the principal components of the tangent shape space using the independent contrasts of shape. The results suggest that empirical data usually show strong degrees of integration in most of the organisms and structures analysed. These are bad news, since strong degree of integration has devastating effects over the phylogenetic reliability, as suggested by our simulations. However, we also propose the existence of other theoretical situations in which strong integration may not translate into convergence between species, like perpendicular orientation of the integration patterns or big total variance relative to the distance between species in the shape space. Finally, geometric morphometrics is applied to the study of the evolution of shape in proteins. There are reasons to think that, because of their modular nature and huge dimensionality, proteins may show different patterns of evolutionary integration. Unfortunately, proteins also show strong functional demands, which influence their evolution and that cause strong integration patterns. Integration is then confirmed as a widespread property in the evolution of shape, which causes poor phylogenetic estimates.
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Sroufe, Paul Dantu Ram. "E-shape analysis". [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/ark:/67531/metadc12201.
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Mio, Giulia <1991>. "SYLVIA PLATH:TAKING SHAPE". Master's Degree Thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/9826.
Testo completoAbstract (sommario):
Unveiling a side of Sylvia Plath that remained hidden for a long time: her passion for visual arts, this work involves discovering the other side of the artistic experience of the young woman, who was fascinated by painting but enraptured by writing.
Retracing the growing path of the poet, it is possible to observe how, during her life, she shared the tensions and beauties of modernity being divided between the two major arts: painting and poetry. Shedding light on the events that brought her to the mental breakdown, the effort to share her sensations and thoughts works as a therapeutic experience.
From her childhood, she tended to tangle drawing and writing in her family letters or invented stories. It was during her student years at Smith College where she attended art lessons that she got closer to painting. Experimenting different range of techniques, her diaries became the canvas on which imprint her life vision, sketches and writing were often mixed up revealing an unexpected outcome.
Plath attachment and dedication to visual arts is the testimony of her versatile nature, which allowed her to investigate the deepened layers of human emotions and uncertainties.
In most cases, different ways of expression work as necessities of the artist to find new artistic methods to shape the perceptions and emotions that otherwise would not find an appropriate realization through their usual technique.
Starting from this point of view, the intrinsic relationship between painting and writing can assume a different connotation. The two arts often move in binary correlation; it was with the Latin poet Horace, that the formula ut pictura poesis took place. Both figurative arts are employed in order to provide beneficiary aesthetic pleasure, and for this reason, their link cannot be underestimated.
Focusing on the double nature of the artist, this work moves on to show and analyse the natural connection between Plath’s writing and figurative art. How one depends on the other and how the visual has influenced the artistic process of the poet in a course that allows the viewer to observe the result of Sylvia Plath artistic effort from a different point of view.
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Fonn, Eivind. "Computing Metrics on Riemannian Shape Manifolds : Geometric shape analysis made practical". Thesis, Norwegian University of Science and Technology, Department of Mathematical Sciences, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9868.
Testo completoAbstract (sommario):
Shape analysis and recognition is a field ripe with creative solutions and innovative algorithms. We give a quick introduction to several different approaches, before basing our work on a representation introduced by Klassen et. al., considering shapes as equivalence classes of closed curves in the plane under reparametrization, and invariant under translation, rotation and scaling. We extend this to a definition for nonclosed curves, and prove a number of results, mostly concerning under which conditions on these curves the set of shapes become manifolds. We then motivate the study of geodesics on these manifolds as a means to compute a shape metric, and present two methods for computing such geodesics: the shooting method from Klassen et. al. and the ``direct'' method, new to this paper. Some numerical experiments are performed, which indicate that the direct method performs better for realistically chosen parameters, albeit not asymptotically.
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Wang, Binhai. "Contour-based shape description and analysis for shape retrieval and classification". Thesis, University of East Anglia, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443090.
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Lu, Bin. "3D Die Shape Optimisation For Net Shape Forging of Aerofoil Blades". Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501609.
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Maurel, Pierre. "Shape gradients, shape warping and medical application to facial expression analysis". Paris 7, 2008. http://www.theses.fr/2008PA077151.
Testo completoAbstract (sommario):
Cette thèse porte sur le domaine des statistiques de formes. Une forme peut être une courbe plane en 2D ou une surface en 3D. Afin de pouvoir définir ces statistiques (moyenne, modes de variation), nous avons étudié plus précisément, dans une première partie plutôt théorique, le recalage et la mise en correspondance de deux formes entre elle. Cela consiste à développer des moyens de déformer une forme sur une autre. Des distances sont définies entre deux formes et une descente de gradient est effectuée pour déformer la première en la seconde. Nous avons donc défini la notion de gradient sur l'espace des formes et généralisé cette définition pour définir des champs de déformations qui ne dérivent plus d'un gradient. Cette notion a été appliquée pour construire une méthode permettant de déformer une courbe en une autre en étant guidé par des points d'amers définissant des correspondances entre ces deux courbes. Dans une seconde partie, nous présentons une application de ces méthodes à l'analyse d'expressions faciales de patients épileptiques en collaboration avec l'équipe du Professeur Patrick Chauvel à l'hôpital de La Timone à Marseille. Nous avons développé des techniques pour quantifier ces expressions faciales, et ainsi pouvoir les comparer entre elles. Nous avons ensuite étudié un moyen de mettre en relation ces expressions faciales (enregistrées pendant des crises d'épilepsies) avec le signal électrique enregistré simultanément dans le cerveau des patients. Cette mise en relation répond à une demande de l'équipe médicale qui se sert de cette information parmi d'autres pour affiner leur diagnosticThis work focuses on the issue of modeling prior knowledge about shapes, an essential problem in Computer Vision. A shape can be a planar curve in 2D or a surface in 3D. In order to model shape statistics, we studied in a first part, rather theoretical, shape warping and matching. We start by defining distances between shapes? Then, in order to deform a shape onto another, we define the gradient of this shape functional and apply a gradient descent scheme. We also developed a generalization of the gradient notion which can take priors into account and which do not derive from any inner product. We used this new notion for defining an extension of the very well-known level set method that can handle landmarks knowledge. On the application side and in collaboration with professor Patrick Chauvel at La Timone Hospital, Marseille, we worked on the task of correlating facial expressions and the electrical activity in the brain during the epileptic seizures. Therefore, we developed a method for fitting a three-dimensional face model under uncontrolled imaging conditions and used this method for analyzing facial expressions of epileptic patients. Finally we present a first step in the direction of being able to interrelate electrical activity produced by the brain during the seizure (and recorded by stereoelectroencephalography electrodes) and the facial expressions
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Ruiz, Pujadas Esmeralda [Verfasser], e Thomas [Akademischer Betreuer] Brox. "Medical image segmentation with shape priors = Medizinische Bildsegmentierung mit Shape Priors". Freiburg : Universität, 2014. http://d-nb.info/1123478627/34.
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Dolog, Rostyslav. "Shape Memory Behavior of Ionomers and Their Compounds". University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1386656054.
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31
Nain, Delphine. "Scale-based decomposable shape representations for medical image segmentation and shape analysis". Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11192006-184858/.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--Computing, Georgia Institute of Technology, 2007.Aaron Bobick, Committee Chair ; Allen Tannenbaum, Committee Co-Chair ; Greg Turk, Committee Member ; Steven Haker, Committee Member ; W. Eric. L. Grimson, Committee Member.
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Valdés, Amaro Daniel Alejandro. "Statistical shape analysis for bio-structures : local shape modelling, techniques and applications". Thesis, University of Warwick, 2009. http://wrap.warwick.ac.uk/3810/.
Testo completoAbstract (sommario):
A Statistical Shape Model (SSM) is a statistical representation of a shape obtained from data to study variation in shapes. Work on shape modelling is constrained by many unsolved problems, for instance, difficulties in modelling local versus global variation. SSM have been successfully applied in medical image applications such as the analysis of brain anatomy. Since brain structure is so complex and varies across subjects, methods to identify morphological variability can be useful for diagnosis and treatment. The main objective of this research is to generate and develop a statistical shape model to analyse local variation in shapes. Within this particular context, this work addresses the question of what are the local elements that need to be identified for effective shape analysis. Here, the proposed method is based on a Point Distribution Model and uses a combination of other well known techniques: Fractal analysis; Markov Chain Monte Carlo methods; and the Curvature Scale Space representation for the problem of contour localisation. Similarly, Diffusion Maps are employed as a spectral shape clustering tool to identify sets of local partitions useful in the shape analysis. Additionally, a novel Hierarchical Shape Analysis method based on the Gaussian and Laplacian pyramids is explained and used to compare the featured Local Shape Model. Experimental results on a number of real contours such as animal, leaf and brain white matter outlines have been shown to demonstrate the effectiveness of the proposed model. These results show that local shape models are efficient in modelling the statistical variation of shape of biological structures. Particularly, the development of this model provides an approach to the analysis of brain images and brain morphometrics. Likewise, the model can be adapted to the problem of content based image retrieval, where global and local shape similarity needs to be measured.
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Peter, Adrian M. "Information geometry for shape analysis probabilistic models for shape matching and indexing /". [Gainesville, Fla.] : University of Florida, 2008. http://purl.fcla.edu/fcla/etd/UFE0022484.
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34
Kockar, Benat. "Shape memory behavior of ultrafine grained NiTi and TiNiPd shape memory alloys". Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2543.
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35
Geurtz, Alexander. "Model based shape estimation /". Lausanne : EPFL, 1993. http://library.epfl.ch/theses/?nr=1180.
Testo completo
36
Schamberger, Stefan. "Shape optimized graph partitioning". [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983282455.
Testo completo
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Alexa, Marc. "Shape spaces from morphing". Phd thesis, [S.l. : s.n.], 2002. http://elib.tu-darmstadt.de/diss/000213.
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38
Zubi, Stephan al. "Active shape structural model". [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=97445107X.
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39
Olsson, Karin, e Therese Persson. "Shape from Silhouette Scanner". Thesis, Linköping University, Department of Science and Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1348.
Testo completoAbstract (sommario):
The availability of digital models of real 3D objects is becoming more and more important in many different applications (e-commerce, virtual visits etc). Very often the objects to be represented cannot be modeled by means of the classical 3D modeling tools because of the geometrical complexity or color texture. In these cases, devices for the automatic acquisition of the shape and the color of the objects (3D scanners or range scanners) have to be used.
The scanner presented in this work, a Shape from silhouette scanner, is very cheap (it is based on the use of a simple digital camera and a turntable) and easy to use. While maintaining the camera on a tripod and the object on the turntable, the user acquires images with different rotation angles of the table. The fusion of all the acquired views enables the production of a digital 3D representation of the object.
Existing Shape from silhouette scanners operate in an indirect way. They subdivide the object definition space in a regular 3D grid and verify that a voxel belongs to the object by verifying that its 2D projection falls inside the silhouette of the corresponding image. Our scanner adopts a direct method: by using a new 3D representation scheme and algorithm, the Marching Intersections data structure, we can directly intersect all the 3D volumes obtained by the silhouettes extracted from the images.
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Dodds, Jake Steven. "Particle Shape and Stiffness". Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/8063.
Testo completoAbstract (sommario):
Particle shape is evaluated on three scales corresponding to form, roundness and roughness. Shape at each of these scales uniquely influences material behavior. The shape of sand grains is largely formed as magma cools. Subsequent cleavage and abrasion change the roundness and roughness of particles. Published results indicate that particle shape influences several aspects of granular systems behavior including stiffness, strength, the evolution of strength anisotropy, dilation, and the development of strain localization.
The crushing of granite creates a particulate material with a unique angular shape. A wide range of experimental studies implemented as part of this research permit assembling a unique database of material parameters and comparing the behavior of several crushed and natural sands. In general, the low roundness of crushed sands leads to higher maximum void ratios, lower small strain stiffnesses, and higher critical state friction angles than more rounded natural sands. It also impacts mortar strength and workability.
Previous studies have emphasized size-controlled segregation. New experimental results show that differences in particle shape can also lead to segregation in a binary granular material. Round or spherical particles are more mobile than angular or flat particles. Then, the greater motion of round or spherical particles in a binary mixture subjected to horizontal or vertical vibration results in their segregation from their angular or flat neighbors.
Particle shape may change significantly with stress in the case of soft particles. Therefore, the presence of shape-deformable particles decreases the stiffness of binary rigid-soft particle mixtures. However, macro-scale measurements with rigid-soft mixtures show higher stiffness than would be expected by volume averaging techniques. A subsequent microscale study shows the formation of backbone chains made of the rigid particles, partially supported by the soft particles which prevent the buckling of the load-carrying chains.
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McKnight, Lorrita L. "Two-dimensional shape blending". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0020/MQ45097.pdf.
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42
Schenk, Merijn. "Shape selectivity in zeolites". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/70569.
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43
Crumley, Zacharia. "Voxel-Space Shape Grammars". Thesis, University of Cape Town, 2012. http://pubs.cs.uct.ac.za/archive/00000783/.
Testo completoAbstract (sommario):
The field of Procedural Generation is being increasingly used in modern content generation for its ability to significantly decrease the cost and time involved. One such area of Procedural Generation is Shape Grammars, a type of formal grammar that operates on geometric shapes instead of symbols.
Conventional shape grammar implementations use mesh representations of shapes, but this has two significant drawbacks. Firstly, mesh representations make Boolean geometry operations on shapes difficult to accomplish. Boolean geometry operations allow us to combine shapes using Boolean operators (and, or, not), producing complex, composite shapes. A second drawback is that sub-, or trans-shape detailing is challenging to achieve. To address these two problems with conventional mesh-based shape grammars, we present a novel extension to shape grammars, in which a voxel representation of the generated shapes is used.
We outline a five stage algorithm for using these extensions and discuss a number of optional enhancements and optimizations. The final output of the algorithm is a detailed mesh model, suitable for use in real-time or offline graphics applications. We also test our extension’s performance and range of output with three categories of testing: performance testing, output range testing, and variation testing.
The results of the testing with our proof-of-concept implementation show that our unoptimized algorithm is slower than conventional shape grammar implementations, with a running time that is O(N^3) for an N^3 voxel grid. However, there is scope for further optimization to our algorithm, which would significantly reduce running times and memory consumption. We outline and discuss several such avenues for performance enhancement.
Additionally, testing reveals that our algorithm is able to successfully produce a broad range of detailed outputs, exhibiting many features that would be very difficult to accomplish using mesh-based shape grammar implementations. This range of 3D models includes fractals, skyscraper buildings, space ships, castles, and more. Further, stochastic rules can be used to produce a variety of models that share a basic archetype, but differ noticeably in their details.
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Dimitrov, Pavel. "Flux invariants for shape". Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19679.
Testo completoAbstract (sommario):
This thesis focuses on a particular class of representations of visual form, those based on the Blum skeleton [6]. We shall argue that such a representation has a number of desirable properties, which any good shape descriptor should possess. We shall begin this discussion in Section 1.1 but will keep it on a relatively high level leaving the details to Chapter 2. We shall then, in Section 1.2, review some of the previous work on skeletonization and identify the major computational difficulties encountered in the past. Finally, in Section 1.3, we shall briefly discuss how the method presented in this thesis deals with those issues and we shall identify the contributions of this work.
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Deghani, Ali. "Shape separation by screening". Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395671.
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46
Ritchie, David W. "Parametric protein shape recognition". Thesis, University of Aberdeen, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266898.
Testo completoAbstract (sommario):
This thesis investigates the use of parametric representations of protein surface shape as a computational method of recognising similar and complementary protein surfaces. Both two-dimensional and three-dimensional shape parametrisations are described. The 2D parametrisation is constructed as an expansion of real spherical harmonic basis functions. These may be augmented by special shape-scaled radial functions, using the Laguerre polynomials, to give a novel 3D parametric "surface skin" representation. Using the special rotational properties of the spherical harmonic functions, the 2D parametric surfaces of a pair of proteins may be rotated into superposition rapidly and accurately. In a similar manner, complementary arrangements of a pair of proteins are generated by finding orientations which maximise the degree of overlap between opposing pairs of 3D skins, thus "docking" the two surfaces. This novel approach to the "protein docking problem" has the form of six-dimensional Fourier correlation. Protein docking using parametric skins is at least as accurate as comparable three-dimensional grid-based Fourier docking correlations, but is around two orders of magnitude faster.
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Underhill, Daniel Martin Lennard. "Ferromagnetic shape memory alloys". Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607746.
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Janan, Faraz. "Shape analysis in mammograms". Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:96aaecce-a7bd-404f-9916-778603dbb396.
Testo completoAbstract (sommario):
The number of women diagnosed with the breast cancer continues to rise year on year. Breast cancer is now the most common type of cancer in the UK, with over 55000 cases reported last year. In most cases, mammography is the first step towards diagnosing breast cancer. However, it continues to have many practical limitations as compared to more sophisticated modalities such as MRI. The relatively low cost of mammography, together with the ever increasing risk of women contracting the disease, has led to many developed countries having a breast screening program. These routine breast screens are taken at different points in time and are called temporal mammograms. Currently, a radiologist tends to qualitatively assess temporal mammograms and look for any abnormalities or suspicious regions that might be of a concern. In this thesis, we develop an automatic shape analysis model that can detect and quantify such changes inside the breast. This will not only help in early diagnosis of the disease, which is key to survival, but will potentially aid prognosis and post treatment care. The core to this thesis is the use of Circular Integral Invariants. We explore its multi-scale properties and use it for image smoothing to reduce image noise and enhance features for segmentation. We implement, modify and enhance a segmentation method which previously has been successfully used to acquire breast regions of interest. We applied such Integral Invariants for shape description, to be used for shape matching as well as for subdividing shapes into sub-regions and quantifying the differences between two such shapes. We combine boundary information with the information from inside a shape, thus eccentrically transforming shapes before describing their structure. We develop a novel false positives reduction method based on Integral Invariants scale space. A second aspect of the thesis is the evaluation of and emphasis on the use of breast density maps against the commonly used intensity maps or x-rays. We find density maps sufficient to use in clinical practice. The methods developed in this thesis aim to help clinicians in making diagnostic decision at the point of case. Our shape analysis model is easy to compute, fast and very general in nature that could be deployed in a wide range of applications, beyond mammography.
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Coates-Muller, Christine. "The shape of shadows". Master's thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/8019.
Testo completoAbstract (sommario):
This is a woman's journey backwards to her people and her place, taking her into deep memory and reconstruction of memory; and yielding moments of darkness she knows she must face, though she is hardly able. It is focused on her need to know her grandmother, and to understand her father's suicide and be reconciled to it. The narrator/protagonist, Catrina, artist and poet, writes a poem raising questions about her family: her grandfather who 'wears his face like blank feathers, night in his throat', her khaki father, her grandmother silently kneading bread. Sensing the presence of her grandmother, Nella, Catrina, keeps receiving small prompts which, because she is open to suggestion, draw her always towards family and home. She is encouraged in this task by Flame, erstwhile TRC Councillor and psychologist practising in London - where Catrina is on a year's sabbatical - to respond to these calls from 'the ancestors', the import of which Flame is fully aware. 'Stories may not be literally or historically true but they could be emotionally true,' Flame tells her. Catrina resists going back, but Flame says that the struggle is now, the past continues in the present and what you do with it, how you use your history, is really about today, not yesterday.
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Schlebusch, Stephen A. "Events that shape genomes". Doctoral thesis, Faculty of Science, 2018. http://hdl.handle.net/11427/30987.
Testo completoAbstract (sommario):
The invention and development of Next Generation Sequencing has opened up new possibilities for exploring the genomes of non-model organisms. For this thesis, a diverse range of non-model species from both plants and animals were used to identify and answer questions of evolutionary interest in four case studies. In doing so, a wide assortment of methodologies were used and developed, taking full advantage of the versatility that whole genome sequencing can provide. The genome of the Natal Long Fingered Bat, Miniopterus natalensis, was assembled to investigate the genetic mechanisms responsible for the evolution of the bat wing. The assembled genome was required to facilitate RNA-seq and ChIP-seq analysis. In addition to the genome assembly and annotation, dN/dS analysis and lncRNA prediction were also conducted. This resulted in a high quality genome assembly with just over 24000 genes being annotated and 227 putative lncRNAs being identified. None of the genetic pathways highlighted by the RNA-seq analysis showed any elevated dN/dS signal, suggesting this was not the loci of evolutionary change. The Amboseli National Park in Kenya has a local population of Yellow baboons (Papio cynocephalus) that has recently come into contact and hybridised with a population of Olive baboons (Papio anubis). A genome assembly of P. cynocephalus was created and used to align low coverage sequencing from 45 baboons, including admixed individuals along with unadmixed individuals from each species. By identifying SNPs that were predictive of the species, hybrid individuals were confirmed and evidence for previous admixture events discovered, such as P. anubis SNPs already at fixation in the P. cynocephalus population at Amboseli. The Ruschioideae are a clade of plants that encompasses the prolific tribe, the Ruschieae, which is comprised of approximately 1500 recently diverged species. An exploratory analysis sequenced two Ruschieae genomes (Polymita steenbokensis and Faucaria felina) along with a sister taxon (Cleretum herrei) from a neighbouring tribe (Dorotheantheae). The three plants were compared to each other in order to try and identify any genetic signatures that could be influencing the rapid speciation. The two Ruschieae species were found to have increased levels of non-tandem duplication within the genome as well as on going transposable element activity when compared to C. herrei. Xerohpyta humilis is a desiccation tolerant plant. In order to further facilitate research into how this is possible, the genome was sequenced and assembled. Irregular data led to the discovery that the plant had a genome duplication as well as a large amount of somatic mutations in its genome. Further analysis confirmed that this pattern of somatic mutations was only present in plants that had undergone multiple cycles of desiccation and rehydration. These apparently disparate topics explored the possibilities and limitations for whole genome sequencing in the study of non-model organisms. Mechanisms of genetic change were examined at the genomic scale, from adaptation and hybridisation to various forms of duplication and mutation. In this way, a large variety of events responsible for the evolutionary change of genomes in plants and animals were analysed in a diverse set of systems.