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Fiorentino, Robert D. "Lexical structure and the nature of linguistic representations." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3896.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.Thesis research directed by: Linguistics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Moore, Barbara Kirsten. "An analysis of representations for protein structure prediction." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/32620.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.Includes bibliographical references (p. 270-279).
by Barbara K. Moore Bryant.
Ph.D.
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LeBlanc, David C. "The generation of phrase-structure representations from principles." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29338.
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Implementations of grammatical theory have traditionally been based upon Context-
Free Grammar (CFG) formalisms which all but ignore questions of learnability. Even implementations which are based upon theories of Generative Grammar (GG), a paradigm which is supposedly motivated by learnability, rarely address such questions. In this thesis we will examine a GG theory which has been formulated primarily to address questions of learnability and present an implementation based upon this theory. The theory argues from Chomsky's definition of epistemological priority that principles which match elements and structures from prelinguistic systems
with elements and structures in linguistic systems are preferable to those which are defined purely linguistically or non-linguistically. A procedure for constructing phrase-structure representations from prelinguistic relations using principles of node percolation (rather than the traditional X-theory of GG theories or phrase-structure rules of CFG theories) is presented and this procedure integrated into a left-right, primarily bottom-up parsing mechanism. Specifically, we present a parsing mechanism
which derives phrase-structure representations of sentences from Case- and 0-relations using a small number of Percolation Principles. These Percolation Principles
simply determine the categorial features of the dominant node of any two adjacent nodes in a representational tree, doing away with explicit phrase structure
rules altogether. The parsing mechanism also instantiates appropriate empty categories using a filler-driven paradigm for leftward argument and non-argument movement. Procedures modelling learnability are not implemented in this work, but the applicability of the presented model to a computational model of language is discussed.Science, Faculty of
Computer Science, Department of
Graduate
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Rateau, Patrick. "Structure et fonctionnement du systeme central des representations sociales." Montpellier 3, 1995. http://www.theses.fr/1995MON30002.
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Un point fondamental de la theorie du noyau central des representations sociales est que le noyau a avant tout une dimension qualitative. Ce n'est pas l'importance quantitative d'un element qui definit sa centralite, mais c'est le fait qu'il donne sa signification a la representation. Ceci explique que l'on peut observer deux elements dont l'importance quantitative est identique et tres forte mais dont l'un est dans le noyau central et l'autre non. Or, l'etude des travaux portant sur la representation du groupe (flament, 1971, 1984 ; moliner, 1988) et la mise en oeuvre d'une serie d'experience amenent a poser l'existence d'une difference qualitative de deux elements pourtant centraux de la representation : l'un serait prioritaire, c'est lui qui gererait veritablement sa signification. Ses liens avec l'ideologie, la culture et l'histoire des sujets semblent par ailleurs tres fort, il s'agirait d'un element normatif. L'autre serait adjoint et aurait davantage un role de mediateur, il specifierait le sens de la representation et serait lie aux pratiques sociales que les sujets developpent frequemment envers l'objet (il s'agirait donc d'un element fonctionnel). On abandonnerait ainsi la notion classique de noyau, pour lui substituer celle de systeme central hierarchise, impliquant un certain nombre de visees theoriques nouvellesOne fundamental point of the social representations' central core theory is that the core gets a quantative dimension above all. This is not the quantitative importance of an element which define is centrality but the fact that it gives sens to the representation. That's why it can be observed two elements quantitatively equals and strong with one in the central core and the other not. However, both the study of works about social representation of an ideal group (flament, 1971,1984 ; moliner, 1988) and the implementation of a series of experimentations, lead to the conclusion that there is a qualitative difference between the two central elements of the representation : one would be an "having priority element". It would really generate the meaning of the representation. Its relation with ideology, culture and history of the group seems to be strong. Then, it would have a normative function. The other one should be an "adjunct element". It would have a mediating role, specificating the meaning of the representation in relation with the social practices that subjects frequently entertain with the object (then it would have a functional function). The classical notion of "core" should be replace with the term of hierarchical central system which implies some new theorical developments
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Livingstone, Sonia M. "Social knowledge and programme structure in representations of television characters." Thesis, University of Oxford, 1987. http://ora.ox.ac.uk/objects/uuid:2adf1878-f117-4c32-870c-9d0ec539bb11.
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It was argued that the social psychology of person perception, mass communications and cultural studies can be related to viewers' representations of television characters. Mass communications needs to incorporate viewers' interpretations and programme structure. Social cognition could satisfy the former need and cultural studies the latter. A literature review showed little research on viewers' interpretations of television programmes. There is a considerable body of research on person perception, gender stereotypes, the effects of viewing and programme structure. A study of viewers' accounts of viewing soap opera showed that they become involved with the characters and find the programmes realistic. Soap opera plays an important role in their lives. Viewers' representations of soap opera characters were examined using multidimensional scaling. This revealed stable, replicable character representations for Dallas, Coronation Street and EastEnders. The representations were compared with the oppositions which structure the programmes, Implicit Personality Theory and Gender Schema Theory. Dallas characters were represented by themes of morality and power/activity. Power was correlated with gender, with some counter-stereotypic females. Coronation Street characters were organised around morality/potency, gender (matriarchal) and approach to life. This related to person prototypes and contrasted with interaction patterns between characters. EastEnders characters were represented by themes of morality/power, gender and approach to life/centrality. Free descriptions validated the attribute ratings and showed further features of the representation. No socio-structural group differences in representation were found. Viewers' character representations were a constructive integration of programme structure and social knowledge. The application of abstract knowledge to a structured domain was discussed. Textual analysis of a narrative identified the 'role of the reader' and textual openness. This was related to stereotypes, narrative expectancies, myth and character representation. Distinct types of divergence in viewers' interpretations of narrative were discovered. Further, a narrative containing two readings was interpreted in four distinct ways by viewers, depending on their perceived relationships with characters. The conclusions and limitations of the research were discussed. Implications for person perception, stereotyping and textual analysis were examined. A taxonomy of factors relating to the interpretation and representation of television drama was presented.
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Peche, Irissarry Macarena. "The reduction of G-ordinary crystalline representations with G-structure." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066467/document.
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Le foncteur D_cris de Fontaine nous permet d'obtenir des isocristaux à partir des représentations cristallines. Pour un groupe reductif G, on s'intéresse à étudier la réduction des réseaux dans une représentation cristalline avec G-structure V, vers les cristaux avec G-structure contenus dans D_cris(V). En utilisant la théorie des modules de Kisin, on donne une description de cette réduction en termes du groupe G, dans le cas où la représentation est (G-)ordinaire. Pour cela, il faut d'abord généraliser la construction de la filtration de Harder-Narasimhan des groupes p-divisibles, donnée par Fargues, aux modules de KisinFontaine’s D_cris functor allows us to associate an isocrystal to any crystalline representation. For a reductive group G, we study the reduction of lattices inside a germ of crystalline representations with G-structure V, to lattices (which are crystals) with G-structure inside D_cris(V). Using Kisin modules theory, we give a description of this reduction in terms of G, in the case when the representation V is (G-)ordinary. In order to do that, first we need to generalize Fargues’ construction of the Harder-Narasimhan filtration for p-divisible groups to Kisin modules
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Hall, Johan. "Transition-Based Natural Language Parsing with Dependency and Constituency Representations." Doctoral thesis, Växjö : Växjö University Press, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2367.
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Komninos, Alexandros. "Leveraging structure for learning representations of words, sentences and knowledge bases." Thesis, University of York, 2018. http://etheses.whiterose.ac.uk/21616/.
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This thesis presents work on learning representations of text and Knowledge Bases by taking into consideration their respective structures. The tasks for which the methods are developed and evaluated on are: Short-text classification, Word Sense Induction and Disambiguation, Knowledge Base Completion with linked text corpora, and large-scale Knowledge Base Question Answering. An introductory chapter states the aims and scope of the thesis, followed by a chapter on technical background and definitions. In chapter 3, the impact of dependency syntax on word representation learning in the context of short-text classification is investigated. A new definition of context in dependency graphs is proposed, which generalizes and extends previous definitions used in word representation learning. The resulting word and dependency feature embeddings are used together to represent dependency graph substructures in text classifiers. In chapter 4, a probabilistic latent variable model for Word Sense Induction and Disambiguation is presented. The model estimates sense clusters using pretrained continuous feature vectors of multiple context types: syntactic, local lexical and global lexical, while the number of sense clusters is determined by the Integrated Complete Likelihood criterion. A model for Knowledge Base Completion with linked text corpora is presented in chapter 5. The proposed model represents potential facts by merging subgraphs of the knowledge base with text through linked entities. The model learns to embed the merged graphs into a lower dimensional space and score the plausibility of the fact with a Multilayer Perceptron. Chapter 6 presents a system for Question Answering on Knowledge Bases. The system learns to decompose questions into entity and relation mentions and score their compatibility with queries on the knowledge base expressed as subgraphs. The model consists of several components trained jointly in order to match parts of the question with parts of a potential query by embedding their corresponding structures in lower dimensional spaces.
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Feiman, Roman. "The Structure and Development of Logical Representations in Thought and Language." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:23845487.
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The expressive power of human thought and language comes from the ability to systematically combine a finite vocabulary of concepts into a boundless number of meaningful thoughts. What properties of conceptual representations enable their combination? Three papers investigate different aspects of the combinatorial system in the context of a single general approach – taking logical concepts as a special case of concepts whose content is completely specified by their combinatorial properties. The first paper looks at infants’ ability to represent two types of goals: approach and avoid, where each goal-type could be represented as the negation of the other. Consistent with past literature, we find evidence of children representing approach at 7 month, but failing to represent avoid at both 7 and 14 months. This suggests that these children cannot combine their representation of approach with a negation operator, possibly because they do not yet have this operator. In the second paper, we continue to look at the emergence of logical negation through the relationship between the emergence of the concept and the words that label it. We find that, although 15-month-olds say the word “no”, they do not understand its logical meaning until 24 months. This is the same age at which they begin to produce the word “not”, comprehend its logical meaning, and use both “no” and “not” to deny the truth of others’ statements. This pattern of results suggest a common limiting factor on the mapping of any word to the concept of logical negation. This factor could be the emergence of the concept, or a linguistic limitation common to both “no” and “not”. The third paper looks at the properties of the combinatorial system in adults, taking linguistic quantifier scope ambiguity phenomena as a case study. Using a priming paradigm, we find evidence for independent combinatorial operations for the universal quantifiers EACH, EVERY and ALL, but common operations for the numbers THREE, FOUR and FIVE. We also find that the semantic operations that compose quantifier meanings abstract away from the verb and noun content of sentences. This suggests a division of labor in adult combinatorial thought, with conceptual content represented separately from the combinatorial properties of concepts.Psychology
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Iyer, Preeti Ramesh [Verfasser]. "Multi-faceted Structure-Activity Relationship Analysis Using Graphical Representations / Preeti Ramesh Iyer." Bonn : Universitäts- und Landesbibliothek Bonn, 2014. http://d-nb.info/1048091465/34.
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Al-Jayrudy, Lubna. "Ideological representations in English and Arabic news reports : a thematic structure analysis." Thesis, Heriot-Watt University, 2011. http://hdl.handle.net/10399/2459.
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The broad aim of this study is to investigate the efficacy of Theme/Rheme analysis in identifying underlying ideologies in English and Arabic news reports. The study takes as its starting point the assumption that the different choices of Theme/Rheme, their organization at the local and global structures and the presentation of Given/New information can elucidate ideological factors that underlie news presentation in English and Arabic. This thesis designs a conceptual framework which combines structural, ideological and linguistic approaches to Discourse Analysis. It also develops an innovative methodological model to analyse Theme/Rheme in Arabic Verbal and Nominal clauses and enhances the linguistic tools to analyse the thematic structures in English and Arabic texts. The thesis applies the developed model, methods and tools to a selected corpus of English and Arabic news reports in order to identify ideological representations of Syria in mainstream online news media. The study seeks to analyse and compare the different choices of Theme/Rheme, nominalization and lexical variations in the thematic structures, on the one hand, and their implications and attribution of causality and responsibility, on the other hand. These issues are investigated in a corpus of English and Arabic news reports during times of political assassinations in Lebanon and the implication of Syrian involvement. Based on the recurrent preferences in the thematic structures of the selected corpus, the study concludes that developed model, methods and tools help identify underlying ideologies in the presentations of Syria in both English and Arabic news reports.
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Jin, Meilan. "Signal Structure for a Class of Nonlinear Dynamic Systems." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6829.
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The signal structure is a partial structure representation for dynamic systems. It characterizes the causal relationship between manifest variables and is depicted in a weighted graph, where the weights are dynamic operators. Earlier work has defined signal structure for linear time-invariant systems through dynamical structure function. This thesis focuses on the search for the signal structure of nonlinear systems and proves that the signal structure reduces to the linear definition when the systems are linear. Specifically, this work: (1) Defines the complete computational structure for nonlinear systems. (2) Provides a process to find the complete computational structure given a state space model. (3) Defines the signal structure for dynamic systems in general. (4) Provides a process to find the signal structure for a class of dynamic systems from their complete computational structure.
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Boucher, Luke. "Learning the structure of artificial grammars : computer simulations and human experiments." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298103.
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Rai, Suranjana, Jagdish Rai, and Andreas Cap@esi ac at. "Group--Theoretical Structure of the Entangled States of N Identical." ESI preprints, 2000. ftp://ftp.esi.ac.at/pub/Preprints/esi904.ps.
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CLEMENT, JULIETTE. "Structure des representations prosodiques developpement normal et pathologique du traitement de la prosodie." Paris 5, 1999. http://www.theses.fr/1999PA05H003.
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Cette these a pour objectifs de determiner la nature des traitements cognitifs de la prosodie, et d'etablir la structure des representations prosodiques. La prosodie de la parole transmet diverses informations dans la communication. Comme les composantes prosodiques peuvent se retrouver dans la musique au niveau de la surface des formes sonores, ce parallele peut inspirer un modele du traitement prosodique. Nous adoptons alors l'hypothese que les traitements de bas-niveau des formes sonores ne dependent pas forcement des dimensions verbale ou musicale, mais qu'ils seraient specifiques aux composantes intonatives et temporelles des sons. A l'etape perceptive, ces parametres acoustiques auraient un statut de "primitives" auditives et a un niveau ulterieur d'integration, nous supposons l'existence de representations prosodiques, ou le resultat des traitements perceptifs specifiques est organise en une configuration. Ces suppositions sont basees sur les resultats de deux series d'experiences. La premiere, realisee avec le paradigme d'interference, met en evidence des traitements elementaires particuliers des indices prosodiques chez les adultes. La deuxieme est effectuee avec la procedure de neutralisation semantique qui permet de se focaliser sur les informations semanticopragmatiques uniquement transmises par la prosodie. Cette deuxieme serie examine la production et l'identification de formes prosodiques significatives lors d'etudes developpementales et comparatives, et etudie la construction progressive des representations prosodiquesThe goals of this thesis is to specify the nature of prosodic cognitive processes, and to highlight the structure of prosodic representations. Speech prosody transmits various information during communication. As prosodic components can be found as well in music at the surface level of sound forms, this parallelism can inspire a model of prosodic processing. We postulate that low level processing of sound forms does not depend on verbal or musical dimensions, but is specific to intonational and temporal components of sounds. During the perceptive stage, the acoustical parameters would have a status of auditory primitives, and at a later integration level, we assume the existence of prosodic representations, in which the result of specific perceptive processing is organized in one single configuration. These assumptions are based on the results of two sets of experiments. The first one, relying on an interference paradigm, demonstrated the existence of specific elementary processing on prosodic cues among adults. The second one is based on a semantic neutralization procedure which allows focusing on semantic and pragmatic information only transmitted by prosody ; in this second set of studies, which examined the production and identification of significant prosodic patterns in developmental and comparative studies, we studied the progressive building of prosodic representations
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De, Daruvar Vincent. "Représentations triangulines avec G-structure." Thesis, Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAX033.
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Soit |G| un groupe réductif déployé sur |mathbf{Q}_p|, |B subset G| un sous-groupe de Borel de |G| et |Tsubset B| un tore maximal déployé. Dans cette thèse nous définissons la notion de représentation trianguline |G|-valuée de |text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p)| et initions l'étude de la variété trianguline correspondante en suivant les travaux de Breuil, Hellmann et Schraen. Pour cela nous introduisons la notion de |(G,varphi,Gamma)|-module sur l'anneau de Robba. Ce sont des |G|-torseurs sur l'anneau de Robba munis d'actions continues d'un Frobenius et du groupe |Gamma = mathbf{Z}_p^times| commutant entre elles. Comme pour les |(varphi,Gamma)|-modules classiques il existe un foncteur pleinement fidèle |D_{text{rig}}^dagger| de la catégorie des représentations |p|-adiques |G|-valuées de |text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p)| vers celle des |(G,varphi,Gamma)|-modules sur l'anneau de Robba.On dit qu'une représentation |p|-adique |G|-valuée |rho : text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p) to G(mathbf{Q}_p)| est trianguline si il existe un |(B,varphi,Gamma)|-module |Theta| tel que |D_{text{rig}}^dagger(rho)| provient de |Theta| par fonctorialité le long de l'inclusion |B subset G|. Un tel |Theta| est appelé une triangulation de |rho|. A une telle triangulation on peut associer un caractère |delta_Theta : T^vee(mathbf{Q}_p) to mathbf{Q}_p^times| que l'on appelle le paramètre de |Theta|. Le premier résultat de la thèse est le fait que les représentations |G|-valuées cristallines sont triangulines. Nous donnons une description explicite des paramètres correspondants.Soit |overline{rho} : text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p) to G(mathbf{F}_p)| une représentation résiduelle, |mathfrak{X}_{overline{rho}}| l'espace rigide analytique paramétrant les déformations de |overline{rho}| et |widehat{T^vee}| l'espace rigide analytique paramétrant les caractères de |T^vee|. On définit |U^{text{tri}}_{text{vreg}} subset mathfrak{X}_{overline{rho}} times widehat{T^vee}| comme étant l'ensemble des couples |(rho,delta)| tel que |delta| est suffisamment régulier et |rho| admet une triangulation de paramètre |delta|. La variété trianguline |X^{text{tri}}_{text{vreg}}(overline{rho})| est définie comme étant l'adhérence de Zariski de |U^{text{tri}}_{text{vreg}}(overline{rho})| dans |mathfrak{X}_{overline{rho}} times widehat{T^vee}|. Le résultat principal de la thèse est le fait que |U^{text{tri}}_{text{vreg}}(overline{rho})| est un ouvert lisse de |X^{text{tri}}_{text{vreg}}(overline{rho})| généralisant ainsi un résultat de Breuil, Hellmann et Schraen au cas des représentations |G|-valuéesLet |G| be a split reductive group over |mathbf{Q}_p|, |B subset G| be a Borel subgroup and |T subset B| be a split maximal torus. In this thesis we define the notion of a |G|-valued trianguline representation of |text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p)| and initiate the study of the corresponding trianguline variety following the works of Breuil, Hellmann and Schraen. For this we introduce the notion of a |(G,varphi,Gamma)|-module over the Robba ring. These are |G|-torsors over the Robba ring endowed with continuous commuting actions of a Frobenius automorphism and of |Gamma = mathbf{Z}_p^times|. As it is the case with classical |(varphi,Gamma)|-modules there exists a fully faithful functor |D_{text{rig}}^dagger| from the category of |G|-valued |p|-adic representations of |text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p)| to the one the |(G,varphi,Gamma)|-modules over the Robba ring.We say that a |p|-adic |G|-valued representation |rho : text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p) to G(mathbf{Q}_p)| is trianguline if there exists a |(B,varphi,Gamma)|-module |Theta| such that |D_{text{rig}}^dagger(rho)| comes from |Theta| by functoriality along the inclusion |B subset G|. Such a |Theta| is called a triangulation of |rho|. To such a triangulation we can associate a caracter |delta_Theta : T^vee(mathbf{Q}_p) to mathbf{Q}_p^times| which we call the parameter of |Theta|. The first result of this thesis is that |G|-valued crystalline representations are trianguline. We also give a concrete description of the corresponding parameters.Let |overline{rho} : text{Gal}(overline{mathbf{Q}_p}/mathbf{Q}_p) to G(mathbf{F}_p)| be a residual representation, |mathfrak{X}_{overline{rho}}| be the rigid analytic space parametrizing deformations of |overline{rho}| and |widehat{T^vee}| be the rigid analytic space parametrizing caracters of |T^vee|. We define |U^{text{tri}}_{text{vreg}} subset mathfrak{X}_{overline{rho}} times widehat{T^vee}| to be the set of couples |(rho,delta)| such that |delta| is sufficiently regular and such that |rho| admits a triangulation of parameter|delta|. The trianguline variety |X^{text{tri}}_{text{vreg}}(overline{rho})| is defined as the Zariski closure of |U^{text{tri}}_{text{vreg}}(overline{rho})| in |mathfrak{X}_{overline{rho}} times widehat{T^vee}|. The principal result of the thesis is that |U^{text{tri}}_{text{vreg}}(overline{rho})| is Zariski open and smooth inside |X^{text{tri}}_{text{vreg}}(overline{rho})|. This generalizes a result of Breuil, Hellmann and Schraen to the setting of |G|-valued representations
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Prindle, Paige Ann. "Publishing, property, and problematic heiresses representations of inheritance in nineteenth-century American women's popular fiction /." Diss., [La Jolla] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p3355845.
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Thesis (Ph. D.)--University of California, San Diego, 2009.Title from first page of PDF file (viewed July 7, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 237-258).
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Tanaka, Junko. "Structure of tensor products of the defining representations of the Lie algebra W1 of Cartan type." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/150387.
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Regnier-Coudert, Olivier. "Bayesian network structure learning using characteristic properties of permutation representations with applications to prostate cancer treatment." Thesis, Robert Gordon University, 2013. http://hdl.handle.net/10059/834.
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Over the last decades, Bayesian Networks (BNs) have become an increasingly popular technique to model data under presence of uncertainty. BNs are probabilistic models that represent relationships between variables by means of a node structure and a set of parameters. Learning efficiently the structure that models a particular dataset is a NP-hard task that requires substantial computational efforts to be successful. Although there exist many families of techniques for this purpose, this thesis focuses on the study and improvement of search and score methods such as Evolutionary Algorithms (EAs). In the domain of BN structure learning, previous work has investigated the use of permutations to represent variable orderings within EAs. In this thesis, the characteristic properties of permutation representations are analysed and used in order to enhance BN structure learning. The thesis assesses well-established algorithms to provide a detailed analysis of the difficulty of learning BN structures using permutation representations. Using selected benchmarks, rugged and plateaued fitness landscapes are identified that result in a loss of population diversity throughout the search. The thesis proposes two approaches to handle the loss of diversity. First, the benefits of introducing the Island Model (IM) paradigm are studied, showing that diversity loss can be significantly reduced. Second, a novel agent-based metaheuristic is presented in which evolution is based on the use of several mutation operators and the definition of a distance metric in permutation spaces. The latter approach shows that diversity can be maintained throughout the search while exploring efficiently the solution space. In addition, the use of IM is investigated in the context of distributed data, a common property of real-world problems. Experiments prove that privacy can be preserved while learning BNs of high quality. Finally, using UK-wide data related to prostate cancer patients, the thesis assesses the general suitability of BNs alongside the proposed learning approaches for medical data modeling. Following comparisons with tools currently used in clinical settings and with alternative classifiers, it is shown that BNs can improve the predictive power of prostate cancer staging tools, a major concern in the field of urology.
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Barch, Jon Craig. "On Measuring Student-Teacher Relationships: Sorting Out Predictors, Outcomes, And Schematic Structure Of Students’ Internal Relationship Representations." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1950.
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Student-teacher relationships have been studied by numerous researchers from a variety of perspectives. Evidence consistently suggests that the quality of student-teacher relationships can have a profound impact on children’s social and cognitive development. Although researchers seem to agree on this point, their theoretical conceptualizations of the relationships and how they measure them are often quite different. This study provides empirical insights for both measurement integration and theory integration regarding students’ internal relationship representations.
Items from 14 different student-teacher relationship instruments were systematically combined and administered as a composite instrument to 628 college students. The participants responded to all items in reference to a single, recent relationship with a high school instructor. This allowed comparative examination of the original 14 scales independently for internal consistency and predictive validity. The study also examined a hypothesized multidimensional structural model of students’ internal representation of their relationship with a teacher based off relational schema theory. An alternative, more parsimonious model was examined as well.
The hypothesized model was not supported by the data. The study demonstrated that multiple measurement models of various items could produce acceptable fit. The study provided evidence as to which of the 170 items from the 14 original scales most closely measure the core of student-teacher relationship quality. The study exemplified the method effect dangers of negative item wording. Finally, the study provided strong evidence for conceptualizing student-teacher relationships as a single, global relationship quality construct.
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Jesper, Segeblad. "Putting a spin on SPINN : Representations of syntactic structure in neural network sentence encoders for natural language inference." Thesis, Linköpings universitet, Interaktiva och kognitiva system, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-139229.
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This thesis presents and investigates a dependency-based recursive neural network model applied to the task of natural language inference. The dependency-based model is a direct extension of a previous constituency-based model used for natural language inference. The dependency-based model is tested on the Stanford Natural Language Inference corpus and is compared to the previously proposed constituency-based model as well as a recurrent Long-Short Term Memory network. The experiments show that the Long-Short Term Memory outperform both the dependency-based models as well as the constituency-based model. It is also shown that what is to be explicitly represented depends on the model dimensionality that one use. With 50-dimensional models, more explicit representations of the dependency structure provides higher accuracies, and the best dependency-based model performs on par with the LSTM. Higher model dimensionalities seem to favor less explicit representations of the dependency structure. We hypothesize that a smaller dimensionality requires a more explicit representation of the relevant linguistic features of the input, while the explicit representation becomes limiting when a higher model dimensionality is used.
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Chai, Yi. "A novel progressive mesh representation method based on the half-edge data structure and √3 subdivision." Thesis, Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5797.
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Progressive mesh (PM) representation can perfectly meet the requirements of generating multi-resolutions for a detailed 3D model. This research proposes a new PM representation method to improve the PM representation storage efficiency and reduce PM generation time. In existing PM representation methods, more than 4 adjacent vertices will be stored for one vertex in the PM representation. Furthermore, the methods always use the inefficient vertex and face list representation during the generation process. In our proposed method, only three vertices are stored by using the √3 subdivision scheme and the efficient half-edge data structure replaces the vertex and face list representation. To evaluate the proposed method, a designed experiment is conducted by using three common testing 3D models. The result illustrates the improvements by comparing to other previous methods.0707671386
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Brito, Matheus Batagini 1985. "Classification and structure of certain representations of quantum affine algebras = Classificação e estrutura de certas representações de álgebras afim quantizadas." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307020.
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Orientadores: Adriano Adrega de Moura, Evgeny MukhinTese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica
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Resumo: Estudamos representações de dimensão finita para uma álgebra afim quantizada a partir de dois pontos de vista distintos. Na primeira parte deste trabalho estudamos o limite graduado de uma certa subclasse de representações irredutíveis. Seja V uma representação de dimensão finita para uma álgebra do tipo A e suponha que V é isomorfa ao produto tensorial de uma afinização minimal por partes cujo peso máximo é a soma de distintos pesos fundamentais por módulos de Kirillov--Reshetikhin cujos pesos máximos são o dobro de um peso fundamental. Provamos que V admite limite graduado L e que L é isomorfo a um módulo de Demazure de nível dois bem como ao produto de fusão dos limites graduados de cada um dos supramencionados fatores tensoriais de V. Provamos ainda que, se a álgebra for do tipo clássica (resp. G), o limite graduado das afinizações minimais (regulares) (resp. módulos de Kirillov--Reshetikhin) são isomorfos ao módulos CV para alguma R^+ partição descrita explicitamente. Na segunda parte provamos que um módulo para a álgebra afim quantizada do tipo B e posto n é manso se, e somente se, ele é fino. Em outras palavras, os geradores da subálgebra de Cartan afim são diagonalizáveis se, e somente se, os autoespaços generalizados associados têm dimensão um. Classificamos tais módulos e descrevemos seus respectivos q-caracteres. Em alguns casos, o q-caracter é descrito por super standard Young tableaux do tipo (2n|1)
Abstract: We study finite--dimensional representations for a quantum affine algebra from two different points of view. In the first part of this work we study the graded limit of a certain subclass of irreducible representations. Let V be a finite--dimensional representation for a quantum affine algebra of type A and assume that V is isomorphic to the tensor product of a minimal affinization by parts whose highest weight is a sum of distinct fundamental weights by Kirillov-Reshetkhin modules whose highest weights are twice a fundamental weight. We prove that V admits a graded limit L and that L is isomorphic to a level-two Demazure module as well as to the fusion product of the graded limits of each of the aforementioned tensor factors of V. We also prove that if the quantum affine algebra is of classical type (resp. type G), the graded limit of (regular) minimal affinizations (resp. Kirillov--Reshetkin modules) are isomorphic to CV-modules for some R^+ partition explicitly described. In the second part we show that a module for the quantum affine algebra of type B and rank n is tame if and only if it is thin. In other words, the Cartan currents are diagonalizable if and only if all joint generalized eigenspaces have dimension one. We classify all such modules and describe their q-characters. In some cases, the q-characters are described by super standard Young tableaux of type (2n|1)
Doutorado
Matematica
Doutor em Matemática
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Milette, Greg P. "Analogical matching using device-centric and environment-centric representations of function." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-050406-145255/.
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Thesis (M.S.)--Worcester Polytechnic Institute.Keywords: Analogy, Design, Functional Modeling, Functional Reasoning, Knowledge Representation, Repertory Grid, SME, Structure Mapping Engine, AI in design. Includes bibliographical references (p.106).
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Piotroski, Janina. "THE EFFECTIVENESS OF USING AN ABSTRACTION-DECOMPOSITION SPACE AS A TOOL FOR CHARACTERIZING A KNOWLEDGE DOMAIN AND ENHANCING LEARNING." Miami University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=miami1161869699.
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Franieck, Maria Leticia Castreghini Fernandes. "Mental representations of parents and family structure of first grade elementary school children from two countries Brazil & Germany ; similarities and differences /." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974365165.
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Franieck, Maria Leticia Castreghini Fernandes. "Mental representations of parents and family structure of the first grade elementary school children from two countries Brazil and Germany: similarities and differences /." [S.l. : s.n.], 2005.
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Brandenburg, Jeffrey Lynn. "Timetrees : a branching-time structure for modeling activity and state in the human-computer interface /." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06062008-164012/.
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Spagnolo, Simone. "Each tale chases another : metaphorical representations, non-linearity and openness of narrative structure in Italian opera from post-WWII to 'It makes no difference'." Thesis, City University London, 2015. http://openaccess.city.ac.uk/13570/.
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This work addresses the demands of framing a theoretical problem and practice-based research and it therefore comprises two parts: a thesis and a composition. The thesis discusses the narrative structure of post-WWII Italian avant-garde opera in conceptual terms and demonstrates how it develops on three principal features: the metaphorical representation of socio-political conditions, the non-linearity of the dramaturgy, and openness to a plurality of interpretations. My composition It makes no difference contributes both as a new musico-theatrical work and an outcome of the discussion presented in the thesis. The main text is composed of three main chapters, each respectively dedicated to the features of socio-political representation, non-linearity and openness. Each chapter is in turn divided into two sub-chapters: the first presents the contextualisation and analysis of post-WWII Italian experimental operas, the second explores It makes no difference in relation to both these operas and the above three features. The discussion examines those works that have most significantly experimented with socio-political representations, non-linearity and openness. These include Luigi Nono’s Intolleranza 1960 (1961), Sylvano Bussotti’s La Passion selon Sade (1966) and Luciano Berio’s Opera (1977). At the same time, it omits both those operas relying on traditional operatic principles and those others that, although being experimental, do not focus on the three features this thesis puts forward. This study considers post-WWII Italian avant-garde opera in cross-disciplinary terms and highlights the necessity of discussing it in relation to disciplines other than those proper to the genre of opera, including prose-theatre, literature, politics and philosophy. The composition, on the other hand, provides a synthesis of the above three features: It makes no difference develops a multi-narrative structure whilst providing a representation of contemporary Italian socio-political life and epitomising the concept of openness. At the same time, it integrates theatrical and literary elements and combines traditional notation and graphic scores.
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Schnackenberg, Andrew K. "Symbolizing Institutional Change: Media Representations and Legality in the Payday Loan and Medical Marijuana Industries." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1405090956.
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Chagheri, Samaneh. "An XML document representation method based on structure and content : application in technical document classification." Thesis, Lyon, INSA, 2012. http://www.theses.fr/2012ISAL0085.
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L’amélioration rapide du nombre de documents stockés électroniquement représente un défi pour la classification automatique de documents. Les systèmes de classification traditionnels traitent les documents en tant que texte plat, mais les documents sont de plus en plus structurés. Par exemple, XML est la norme plus connue et plus utilisée pour la représentation de documents structurés. Ce type des documents comprend des informations complémentaires sur l'organisation du contenu représentées par différents éléments comme les titres, les sections, les légendes etc. Pour tenir compte des informations stockées dans la structure logique, nous proposons une approche de représentation des documents structurés basée à la fois sur la structure logique du document et son contenu textuel. Notre approche étend le modèle traditionnel de représentation du document appelé modèle vectoriel. Nous avons essayé d'utiliser d'information structurelle dans toutes les phases de la représentation du document: -procédure d'extraction de caractéristiques, -La sélection des caractéristiques, -Pondération des caractéristiques. Notre deuxième contribution concerne d’appliquer notre approche générique à un domaine réel : classification des documents techniques. Nous désirons mettre en œuvre notre proposition sur une collection de documents techniques sauvegardés électroniquement dans la société CONTINEW spécialisée dans l'audit de documents techniques. Ces documents sont en format représentations où la structure logique est non accessible. Nous proposons une solution d’interprétation de documents pour détecter la structure logique des documents à partir de leur présentation physique. Ainsi une collection hétérogène en différents formats de stockage est transformée en une collection homogène de documents XML contenant le même schéma logique. Cette contribution est basée sur un apprentissage supervisé. En conclusion, notre proposition prend en charge l'ensemble de flux de traitements des documents partant du format original jusqu’à la détermination de la ses classe Dans notre système l’algorithme de classification utilisé est SVMRapid improvement in the number of documents stored electronically presents a challenge for automatic classification of documents. Traditional classification systems consider documents as a plain text; however documents are becoming more and more structured. For example, XML is the most known and used standard for structured document representation. These documents include supplementary information on content organization represented by different elements such as title, section, caption etc. We propose an approach on structured document classification based on both document logical structure and its content in order to take into account the information present in logical structure. Our approach extends the traditional document representation model called Vector Space Model (VSM). We have tried to integrate structural information in all phases of document representation construction: -Feature extraction procedure, -Feature selection, -Feature weighting. Our second contribution concerns to apply our generic approach to a real domain of technical documentation. We desire to use our proposition for classifying technical documents electronically saved in CONTINEW; society specialized in technical document audit. These documents are in legacy format in which logical structure is inaccessible. Then we propose an approach for document understanding in order to extract documents logical structure from their presentation layout. Thus a collection of heterogeneous documents in different physical presentations and formats is transformed to a homogenous XML collection sharing the same logical structure. Our contribution is based on learning approach where each logical element is described by its physical characteristics. Therefore, our proposal supports whole document transformation workflow from document’s original format to being classified. In our system SVM has been used as classification algorithm
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Bonetto, Eric. "Représentations sociales et identité sociale : le rôle des représentations sociales et de leur structure dans l'affiliation au groupe." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0282.
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L’observation de Jahoda (1988) concernant le manque de test de la théorie des représentations sociales demeure pertinente à propos des enjeux identitaires portés par les représentations sociales. Cette thèse s’intéresse tout particulièrement au rôle de ces représentations dans l’affiliation au groupe. Selon une telle perspective, elle se place à l’articulation de l’approche structurale des représentations sociales et de la perspective de l’identité sociale. Douze études testent différentes hypothèses dans le cadre de cette articulation. Les études 1a (N = 324) et 1b (N = 268) s’intéressent au potentiel effet de la structure des représentations sociales sur l’identification au groupe. Les études 2, 3a et b, 4a et b (de N = 143 à N = 358) s’intéressent au potentiel rôle des RS dans la reconnaissance des membres du groupe et la prototypicalité de ceux-ci. Les études 3a et b, 4a et b, 5a et b (de N = 161 à N = 358) explorent la valeur sociale des représentations sociales. Enfin, les études 6a, b et c (de N = 49 à N = 52) traitent du partage perçu dans le cadre de l’approche structurale des représentations sociales. Les conséquences pour la théorie des représentations sociales des résultats inconsistants observés sont discutées à la lumière des considérations d’ordre épistémologique de Popper et Lakatos. Différentes perspectives de recherches sont également présentées,certaines étant assorties d’études empiriquesThe observation of Jahoda (1988) about the lack of test of the theory of social representations remains relevant about the identity features of SRs. This PhD thesis is particularly interested in the role of these representations in the affiliation to the group. In this perspective, it takes place at the articulation between the structural approach to social representations and the social identity perspective. Twelve studies test different hypotheses in the framework of this articulation. Studies 1a (N = 324) and 1b (N = 268) are interested in the potential effect of the structure of social representations on group identification. Studies 2, 3a and b, 4a and b (from N = 143 to N = 358) are interested in the potential role of SRs in the recognition of group members and in their prototypicality. Studies 3a and b, 4a and b, 5a and b (from N = 161 to N = 358) explore the social value of social representations. Finally, studies 6a, b and c (from N = 49 to N = 52) deal with perceived sharedness in the structural approach to social representations. The consequences for the theory of social representations of theinconsistent results observed are discussed in the light of Popper’s and Lakatos’ epistemological considerations. Different research perspectives are also presented, some being accompanied of empirical studies
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Gurung, Topraj. "Compact connectivity representation for triangle meshes." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47709.
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Many digital models used in entertainment, medical visualization, material science, architecture, Geographic Information Systems (GIS), and mechanical Computer Aided Design (CAD) are defined in terms of their boundaries. These boundaries are often approximated using triangle meshes. The complexity of models, which can be measured by triangle count, increases rapidly with the precision of scanning technologies and with the need for higher resolution. An increase in mesh complexity results in an increase of storage requirement, which in turn increases the frequency of disk access or cache misses during mesh processing, and hence decreases performance. For example, in a test application involving a mesh with 55 million triangles in a machine with 4GB of memory versus a machine with 1GB of memory, performance decreases by a factor of about 6000 because of memory thrashing. To help reduce memory thrashing, we focus on decreasing the average storage requirement per triangle measured in 32-bit integer references per triangle (rpt).
This thesis covers compact connectivity representation for triangle meshes and discusses four data structures:
1. Sorted Opposite Table (SOT), which uses 3 rpt and has been extended to support tetrahedral meshes.
2. Sorted Quad (SQuad), which uses about 2 rpt and has been extended to support streaming.
3. Laced Ring (LR), which uses about 1 rpt and offers an excellent compromise between storage compactness and performance of mesh traversal operators.
4. Zipper, an extension of LR, which uses about 6 bits per triangle (equivalently 0.19 rpt), therefore is the most compact representation.
The triangle mesh data structures proposed in this thesis support the standard set of mesh connectivity operators introduced by the previously proposed Corner Table at an amortized constant time complexity. They can be constructed in linear time and space from the Corner Table or any equivalent representation. If geometry is stored as 16-bit coordinates, using Zipper instead of the Corner Table increases the size of the mesh that can be stored in core memory by a factor of about 8.
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Campagnolo, Alberto. "Transforming structured descriptions to visual representations : an automated visualization of historical bookbinding structures." Thesis, University of the Arts London, 2015. http://ualresearchonline.arts.ac.uk/8749/.
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In cultural heritage, the documentation of artefacts can be both iconographic and textual, i.e. both pictures and drawings on the one hand, and text and words on the other are used for documentation purposes. This research project aims to produce a methodology to transform automatically verbal descriptions of material objects, with a focus on bookbinding structures, into standardized and scholarly-sound visual representations. In the last few decades, the recording and management of documentation data about material objects, including bookbindings, has switched from paper-based archives to databases, but sketches and diagrams are a form of documentation still carried out mostly by hand. Diagrams hold some unique information, but often, also redundant information already secured through verbal means within the databases. This project proposes a methodology to harness verbal information stored within a database and automatically generate visual representations. A number of projects within the cultural heritage sector have applied semantic modelling to generate graphic outputs from verbal inputs. None of these has considered bookbindings and none of these relies on information already recorded within databases. Instead they develop an extra layer of modelling and typically gather more data, specifically for the purpose of generating a pictorial output. In these projects qualitative data (verbal input) is often mixed with quantitative data (measurements, scans, or other direct acquisition methods) to solve the problems of indeterminateness found in verbal descriptions. Also, none of these projects has attempted to develop a general methodology to ascertain the minimum amount ii of information that is required for successful verbal-to-visual transformations for material objects in other fields. This research has addressed these issues. The novel contributions of this research include: (i) a series of methodological recommendations for successful automated verbal-to-visual intersemiotic translations for material objects — and bookbinding structures in particular — which are possible when whole/part relationships, spatial configurations, the object’s logical form, and its prototypical shapes are communicated; (ii) the production of intersemiotic transformations for the domain of bookbinding structures; (iii) design recommendations for the generation of standardized automated prototypical drawings of bookbinding structures; (iv) the application — never considered before — of uncertainty visualization to the field of the archaeology of the book. This research also proposes the use of automatically generated diagrams as data verification tools to help identify meaningless or wrong data, thus increasing data accuracy within databases.
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Kanning, Nils. "On the integrable structure of super Yang-Mills scattering amplitudes." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17663.
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Die maximal supersymmetrische Yang-Mills-Theorie im vierdimensionalen Minkowski-Raum ist ein außergewöhnliches Modell der mathematischen Physik. Dies gilt vor allem im planaren Limes, in dem die Theorie integrabel zu sein scheint. So sind etwa ihre Streuamplituden auf Baumgraphenniveau Invarianten einer Yangschen Algebra, die die superkonforme Algebra psu(2,2|4) beinhaltet. Diese unendlichdimmensionale Symmetrie ist ein Kennzeichen für Integrabilität. In dieser Dissertation untersuchen wir Verbindungen zwischen solchen Amplituden und integrablen Modellen, um Grundlagen für eine effiziente, auf der Integrabilität basierende Berechnung von Amplituden zu legen. Dazu charakterisieren wir Yangsche Invarianten innerhalb der Quanten-Inverse-Streumethode, die Werkzeuge zur Behandlung integrabler Spinketten bereitstellt. In diesem Rahmen entwickeln wir Methoden zur Konstruktion Yangscher Invarianten. Wir zeigen, dass der algebraische Bethe-Ansatz für die Erzeugung von Yangschen Invarianten für u(2) anwendbar ist. Die zugehörigen Bethe-Gleichungen lassen sich leicht lösen. Unser Zugang erlaubt es zudem diese Invarianten als Zustandssummen von Vertexmodellen zu interpretieren. Außerdem führen wir ein unitäres Graßmannsches Matrixmodell zur Berechnung Yangscher Invarianten mit Oszillatordarstellungen von u(p,q|m) ein. In einem Spezialfall reduziert es sich zu dem Brezin-Gross-Witten-Model. Wir wenden eine auf Bargmann zurückgehende Integraltransformation auf unser Matrixmodell an, welche die Oszillatoren in Spinor-Helizitäts-artige Variablen überführt. Dadurch gelangen wir zu einer Weiterentwicklung der Graßmann-Integralformulierung bestimmter Amplituden. Die maßgeblichen Unterschiede sind, dass wir in der Minkowski-Signatur arbeiten und die Integrationskontur auf die unitäre Gruppenmannigfaltigkeit festgelegt ist. Wir vergleichen durch unser Integral gegebene Yangsche Invarianten mit Amplituden und kürzlich eingeführten Deformationen derselben.The maximally supersymmetric Yang-Mills theory in four-dimensional Minkowski space is an exceptional model of mathematical physics. Even more so in the planar limit, where the theory is believed to be integrable. In particular, the tree-level scattering amplitudes were shown to be invariant under the Yangian of the superconformal algebra psu(2,2|4). This infinite-dimensional symmetry is a hallmark of integrability. In this dissertation we explore connections between these amplitudes and integrable models. Our aim is to lay foundations for an efficient integrability-based computation of amplitudes. To this end, we characterize Yangian invariants within the quantum inverse scattering method, which is an extensive toolbox for integrable spin chains. Making use of this setup, we develop methods for the construction of Yangian invariants. We show that the algebraic Bethe ansatz can be specialized to yield Yangian invariants for u(2). Our approach also allows to interpret these Yangian invariants as partition functions of vertex models. What is more, we establish a unitary Graßmannian matrix model for the construction of u(p,q|m) Yangian invariants with oscillator representations. In a special case our formula reduces to the Brezin-Gross-Witten model. We apply an integral transformation due to Bargmann to our unitary Graßmannian matrix model, which turns the oscillators into spinor helicity-like variables. Thereby we are led to a refined version of the Graßmannian integral formula for certain amplitudes. The most decisive differences are that we work in Minkowski signature and that the integration contour is fixed to be a unitary group manifold. We compare Yangian invariants defined by our integral to amplitudes and recently introduced deformations thereof.
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Soares, Telma Woerle de Lima. "Estruturas de dados eficientes para algoritmos evolutivos aplicados a projeto de redes." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-28052009-163303/.
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Problemas de projeto de redes (PPRs) são muito importantes uma vez que envolvem uma série de aplicações em áreas da engenharia e ciências. Para solucionar as limitações de algoritmos convencionais para PPRs que envolvem redes complexas do mundo real (em geral modeladas por grafos completos ou mesmo esparsos de larga-escala), heurísticas, como os algoritmos evolutivos (EAs), têm sido investigadas. Trabalhos recentes têm mostrado que estruturas de dados adequadas podem melhorar significativamente o desempenho de EAs para PPRs. Uma dessas estruturas de dados é a representação nó-profundidade (NDE, do inglês Node-depth Encoding). Em geral, a aplicação de EAs com a NDE tem apresentado resultados relevantes para PPRs de larga-escala. Este trabalho investiga o desenvolvimento de uma nova representação, baseada na NDE, chamada representação nó-profundidade-grau (NDDE, do inglês Node-depth-degree Encoding). A NDDE é composta por melhorias nos operadores existentes da NDE e pelo desenvolvimento de novos operadores de reprodução possibilitando a recombinação de soluções. Nesse sentido, desenvolveu-se um operador de recombinação capaz de lidar com grafos não-completos e completos, chamado EHR (do inglês, Evolutionary History Recombination Operator). Foram também desenvolvidos operadores de recombinação que lidam somente com grafos completos, chamados de NOX e NPBX. Tais melhorias tem como objetivo manter relativamente baixa a complexidade computacional dos operadores para aumentar o desempenho de EAs para PPRs de larga-escala. A análise de propriedades de representações mostrou que a NDDE possui redundância, assim, foram propostos mecanismos para evitá-la. Essa análise mostrou também que o EHR possui baixa complexidade de tempo e não possui tendência, além de revelar que o NOX e o NPBX possuem uma tendência para árvores com topologia de estrela. A aplicação de EAs usando a NDDE para PPRs clássicos envolvendo grafos completos, tais como árvore geradora de comunicação ótima, árvore geradora mínima com restrição de grau e uma árvore máxima, mostrou que, quanto maior o tamanho das instâncias do PPR, melhor é o desempenho relativo da técnica em comparação com os resultados obtidos com outros EAs para PPRs da literatura. Além desses problemas, um EA utilizando a NDE com o operador EHR foi aplicado ao PPR do mundo real de reconfiguração de sistemas de distribuição de energia elétrica (envolvendo grafos esparsos). Os resultados mostram que o EHR possibilita reduzir significativamente o tempo de convergência do EANetwork design problems (NDPs) are very important since they involve several applications from areas of Engineering and Sciences. In order to solve the limitations of traditional algorithms for NDPs that involve real world complex networks (in general, modeled by large-scale complete or sparse graphs), heuristics, such as evolutionary algorithms (EAs), have been investigated. Recent researches have shown that appropriate data structures can improve EA performance when applied to NDPs. One of these data structures is the Node-depth Encoding (NDE). In general, the performance of EAs with NDE has presented relevant results for large-scale NDPs. This thesis investigates the development of a new representation, based on NDE, called Node-depth-degree Encoding (NDDE). The NDDE is composed for improvements of the NDE operators and the development of new reproduction operators that enable the recombination of solutions. In this way, we developed a recombination operator to work with both non-complete and complete graphs, called EHR (Evolutionary History Recombination Operator). We also developed two other operators to work only with complete graphs, named NOX and NPBX. These improvements have the advantage of retaining the computational complexity of the operators relatively low in order to improve the EA performance. The analysis of representation properties have shown that NDDE is a redundant representation and, for this reason, we proposed some strategies to avoid it. This analysis also showed that EHR has low running time and it does not have bias, moreover, it revealed that NOX and NPBX have bias to trees like stars. The application of an EA using the NDDE to classic NDPs, such as, optimal communication spanning tree, degree-constraint minimum spanning tree and one-max tree, showed that the larger the instance is, the better the performance will be in comparison whit other EAs applied to NDPs in the literatura. An EA using the NDE with EHR was applied to a real-world NDP of reconfiguration of energy distribution systems. The results showed that EHR significantly decrease the convergence time of the EA
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Large, Edward Wilson. "Dynamic representation of musical structure." Connect to resource, 1994. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osub42551808.
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Thesis (Ph. D.)--Ohio State University, 1994.Advisor: J.B. Pollack, Dept. of Computer and Information Sciences. Includes bibliographical references (leaves 197-208). Available online via OhioLINK's ETD Center.
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Plate, Tony A. "Holographic reduced representation : distributed representation for cognitive structures /." Stanford, Calif. : CSLI, 2003. http://www.loc.gov/catdir/toc/uchi051/2003043513.html.
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Mintram, Robert C. "Vector representations of structured data." Thesis, Southampton Solent University, 2002. http://ssudl.solent.ac.uk/624/.
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The connectionist approach to creating vector representations (VREPs) of structured data is usually implemented by artificial neural network (ANN) architectures. ANNs are trained on a representative corpus and can then demonstrate some degree of generalization to novel data. In this context, structured data are typically trees, the leaf nodes of which are assigned some n-element (often binary) vector representation. The strategy used to encode the leaf data and the width of the consequent vectors can have an impact on the encoding performance of the ANN architecture. In this thesis the architecture of principle interest is called simplified recursive auto associative memory, (S)RAAM, which was devised to provide a theoretical model for abother architecture called recursive auto associative memory, RAAM. Research continues in RAAMs in terms of improving their learning ability, understanding the features that are encoded and improving generalization. (S)RAAM is a mathematical model that lends itself more readily to addressing these issues. Usually ANNs designed to encode structured data will, as a result of training, simultaneously create an encoder function to transform the data into vectors and a decoder function to perform the reverse transformation. (S)RAAM is a mathematical model that lends itself more readily to addressing these issues. Usually ANNs designed to encode structured data will, as a result of training, simultaneously create an encoder function to transform the data into vectors and a decoder function to perform the reverse transformation. (S)RAAM as a model of this process was designed to follow this paradigm. It is shown that this is not strictly necessary and that encoder and decoder functions can be created at separate times, their connection being maintained by the data unpon which they operate. This leads to a new, more versatile model called, in this thesis, the General Encoder Decoder, GED. The GED, like (S)RAAM, is implemented as an algorithm rather than a neural network architecture. The thesis contends that the broad scope of the GED model makes it a versatile experimental vehicle supporting research into key properties of VREPs. In particular these properties include the strategy used to encode the leaf tokens within tree structures and the features of these structures that are preferentially encoded
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LIBERATI, BRUNO. "CAPITALISM REPRESENTATIONS IN BRAZILIAN MODERN CINEMA: ANALYSIS OF THE MOVIES UNDER THE INFLUENCE OF A STRUCTURE OF FEELING THAT STIMULATED THE FLOURISHING OF A CULTURAL SCENE DURING THE 50 S AND 60 S." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2013. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=26933@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
O objetivo desta pesquisa é identificar e analisar as representações do capitalismo observadas em obras da fase moderna do cinema brasileiro. Inaugurada na década de 1950, tal etapa desdobra-se no Cinema Novo, cuja trajetória estende-se até o fim dos anos 1970. Compreende-se que os filmes analisados estão sob influência de um tipo de estrutura de sentimento romântico - de afirmação de uma brasilidade revolucionária - que vicejou e se reconfigurou naquele período considerado utópico. O estudo identifica uma transformação nessa estrutura do sentir, a partir do golpe de 1964 e, sobretudo, dos desdobramentos do AI-5. Percebe-se, contudo, que certos conteúdos mobilizadores desse sentir permanecem como elementos residuais, influindo na ideologia, nos procedimentos estéticos e na prática cinematográfica de artistas e intelectuais que resistiram à chamada modernização-autoritária-conservadora da sociedade brasileira. Tal consideração permite a análise de filmes que fogem à cronologia associada ao esgotamento do movimento do Cinema Novo, incluindo obras que avançam pela década de 1980.
The goal was to identify and analyze the representations of capitalism observed in Brazilian s modern Cinema. Beginning in the 50 s, with an introduction of a neorealistic approach, this phase in the country s movie scene became what s known as Cinema Novo, that happened during the 60 s. It s understood that the movies being analyzed were under a romantic structure of feeling – an affirmation of revolutionary Brazility – that bloom and changed that period, considered utopic. Under that investigation eleven movies produced between 1950 and 1969 were analyzed.
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Coelho, Mollo Dimitri. "Deflating representation : computation, structure, and content." Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/deflating-representation(12dbb208-d5af-4695-a628-2a87556c8e8e).html.
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The present work focuses on the notions of representation and computation, and the explanatory role they play in the cognitive sciences. I put forward a deflationary view of representational content, and argue that explanatory internal states in the cognitive sciences are primarily individuated by their computational structure, rather than by content. In Part I, I survey the mainstream accounts of representation and content present in the philosophical literature: functional role semantics, informational semantics, teleosemantics, and structural representation. I also briey examine some of the crucial issues that any satisfactory theory of content has to tackle, with special attention to the problem of indeterminacy of content. I present and develop, in Part II, a version of the mechanistic view of concrete computation able to account for how cognitive systems compute, and for how to individuate their computational structures. The account avoids pancomputationalism and triviality of computation, yielding a robust, objective theory of computation in physical systems. With this mechanistic view of concrete computation in hand, in Part III I present my deflationary approach to representation, which shifts much of the explanatory burden in making sense of cognition onto computational structures. I examine interpretational semantics as a promising precursor of my view. I propose several modifications to interpretational semantics, producing a theory close to structural representation, but with marked deflationary leanings. On that basis, two deflationary paths are examined: content pragmatism, and mild realism about content. I provide reasons to prefer the latter approach, though I take both paths to be promising. The resulting deflated notion of representation, wedded to a solid notion of computational structure, is advantageous insofar as it dissolves metaphysical puzzles related to content-fixation and indeterminacy, while preserving a notion of representation robust enough to play an important explanatory role in the contemporary study of cognition.
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Brady, Timothy F. "Structured representations in visual working memory." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68420.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 177-195).
How much visual information can we hold in mind at once? A large body of research has attempted to quantify the capacity of visual working memory by focusing on how many individual objects or visual features can be actively maintained in memory. This thesis presents a novel theoretical framework for understanding working memory capacity, suggesting that our memory representations are complex and structured even for simple visual displays, and formalizing such structured representations is necessary to understand the architecture and capacity of visual working memory. Chapter 1 reviews previous empirical research on visual working memory capacity, and argues that an understanding of memory capacity requires moving beyond quantifying how many items people can remember and instead focusing on the content of our memory representations. Chapter 2 argues for structured memory representations by demonstrating that we encode a summary of all of the items on a display in addition to information about particular items, and use both item and summary information to complete working memory tasks. Chapter 3 describes a computational model that formalizes the roles of perceptual organization and the encoding of summary statistics in visual working memory, and provides a way to quantify capacity even in the presence of richer, more structured memory representations. This formal framework predicts how well observers will be able to remember individual working memory displays, rather than focusing on average performance across many displays. Chapter 4 uses information theory to examine visual working memory through the framework of compression, and demonstrates that introducing regularities between items allows us to encode more colors in visual working memory. Thus, working memory capacity needs to be understood by taking into account learned knowledge, rather than simply focusing on the number of items to be remembered. Together, this research suggests that visual working memory capacity is best characterized by structured representations where prior knowledge influences how much can be stored and displays are encoded at multiple levels of abstraction.
by Timothy F. Brady.
Ph.D.
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Bandyopadhyay, Bortik. "Querying Structured Data via Informative Representations." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595447189545086.
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Eidehall, Andreas. "Tensor representation of 3D structures." Thesis, Linköping University, Department of Electrical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1241.
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This is a thesis written for a master's degree at the Computer Vision Laboratory, University of Linköping. An abstract outer product is defined and used as a bridge to reach 2:nd and 4:th order tensors. Some applications of these in geometric analysis of range data are discussed and illustrated. In idealized setups, simple geometric objects, like spheres or polygons, are successfully detected. Finally, the generalization to n:th order tensors for storing and analysing geometric information is discussed.
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Muadz, Husni. "Coordinate structures: A planar representation." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185527.
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In this dissertation, I pursue the idea suggested in Chomsky (1982) that coordination should be treated as an object with three dimensions. I propose a planar model to account for the longstanding problems of coordination. The types of phenomena studied here are related to Phrasal Coordinations, Gapping, Verb Phrase Deletion, and Right-Node Raising. I claim that a coordinate sentence, unlike a simple one, is too expansive a domain for the Principles of Universal Grammar (UG) to hold. The relevant domain for the application of UG principles is each separate "component part" of the coordinate sentence. The "component parts", referred to here as planes, are elements of the coordinate sentence which have the same formal properties as simple sentences. Thus, under the planar model, a coordinate sentence has a number of "simple sentences" or planes. Intuitively, a plane, like a simple sentence, can be thought of as a complete functional complex in which all grammatical functions compatible with its head are realized. Given this, I argue that the well-formedness of a coordinate structure depends on whether or not each of its planes obeys the principles of UG. The planar model adopts the idea that conjuncts or disjuncts in coordination are based generated at D-Structure. It is claimed that no deletions or empty nodes exists in any type of coordinate structures. I show that the absence of some elements in coordination, e.g. a verb in Gapping, is a phonetic phenomenon, which occurs only as a result of the linearization process. At the other levels of representation, such as D-Structure, S-Structure, and Logical Form, all materials are present in each plane; thus, under the planar model, we do not need to invoke a deletion rule or the existence of some empty node in those levels of representation. Given this model, I show that the principles and parameters approach of GB can in fact give a unified treatment of coordination. I demonstrate that this can be done without recourse to construction-specific stipulation.
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Su, Guolong Ph D. Massachusetts Institute of Technology. "Composition structures for system representation." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111999.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 171-183).
This thesis discusses parameter estimation algorithms for a number of structures for system representation that can be interpreted as different types of composition. We refer to the term composition as the systematic replacement of elements in an object by other object modules, where the objects can be functions that have a single or multiple input variables as well as operators that work on a set of signals of interest. In general, composition structures can be regarded as an important class of constrained parametric representations, which are widely used in signal processing. Different types of composition are considered in this thesis, including multivariate function composition, operator composition that naturally corresponds to cascade systems, and modular composition that we refer to as the replacement of each delay element in a system block diagram with an identical copy of another system module. There are a number of potential advantages of the use of composition structures in signal processing, such as reduction of the total number of independent parameters that achieves representational and computational efficiency, modular structures that benefit hardware implementation, and the ability to form more sophisticated models that can represent significantly larger classes of systems or functions. The first part of this thesis considers operator composition, which is an alternative interpretation of the class of cascade systems that has been widely studied in signal processing. As an important class of linear time-invariant (LTI) systems, we develop new algorithms to approximate a two-dimensional (2D) finite impulse response (FIR) filter as a cascade of a pair of 2D FIR filters with lower orders, which can gain computational efficiency. For nonlinear systems with a cascade structure, we generalize a two-step parameter estimation algorithm for the Hammerstein model, and propose a generalized all-pole modeling technique with the cascade of multiple nonlinear memoryless functions and LTI subsystems. The second part of this thesis discusses modular composition, which replaces each delay element in a FIR filter with another subsystem. As an example, we propose the modular Volterra system where the subsystem has the form of the Volterra series. Given statistical information between input and output signals, an algorithm is proposed to estimate the coefficients of the FIR filter and the kernels of the Volterra subsystem, under the assumption that the coefficients of the nonlinear kernels have sufficiently small magnitude. The third part of this thesis focuses on composition of multivariate functions. In particular, we consider two-level Boolean functions in the conjunctive or disjunctive normal forms, which can be considered as the composition of one-level multivariate Boolean functions that take the logical conjunction (or disjunction) over a subset of binary input variables. We propose new optimization-based approaches for learning a two-level Boolean function from a training dataset for classification purposes, with the joint criteria of accuracy and simplicity of the learned function.
by Guolong Su.
Ph. D.
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Sadeghi, Kayvan. "Graphical representation of independence structures." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:86ff6155-a6b9-48f9-9dac-1ab791748072.
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In this thesis we describe subclasses of a class of graphs with three types of edges, called loopless mixed graphs (LMGs). The class of LMGs contains almost all known classes of graphs used in the literature of graphical Markov models. We focus in particular on the subclass of ribbonless graphs (RGs), which as special cases include undirected graphs, bidirected graphs, and directed acyclic graphs, as well as ancestral graphs and summary graphs. We define a unifying interpretation of independence structure for LMGs and pairwise and global Markov properties for RGs, discuss their maximality, and, in particular, prove the equivalence of pairwise and global Markov properties for graphoids defined over the nodes of RGs. Three subclasses of LMGs (MC, summary, and ancestral graphs) capture the modified independence model after marginalisation over unobserved variables and conditioning on selection variables of variables satisfying independence restrictions represented by a directed acyclic graph (DAG). We derive algorithms to generate these graphs from a given DAG or from a graph of a specific subclass, and we study the relationships between these classes of graphs. Finally, a manual and codes are provided that explain methods and functions in R for implementing and generating various graphs studied in this thesis.
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Dias, Pierre. "Les représentations spatiales de la ville et les mobilités quotidiennes au prisme des positions sociales : une approche socio-cognitive des ségrégations socio-spatiales." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAG003/document.
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Depuis les premières formes d’urbanisme, les villes sont façonnées par des constructions idéologiques qui impactent sur le quotidien des individus et sur les ségrégations socio-spatiales. Notre questionnement général porte sur ce contexte, et plus particulièrement sur la façon dont s’objectivent les différentes positions occupées dans la structure sociale par les représentations et les pratiques quotidiennes de l’espace urbain. L’étude de cinq différentes représentations socio-spatiales au sein des agents de l’Université de Strasbourg aura permis de mettre en évidence l’existence d’un principe d’homologie structurale entre les dimensions cognitives, spatiales et sociales de la relation individu-milieu. Certains groupes entretiennent une relation fonctionnelle à la ville traduisant la complexité des lieux fréquentés. À l’inverse, d’autres groupes entretiennent une relation évaluative qui se détache des fréquentations pour se concentrer sur des lieux plus ou moins « emblématiques ». Or, ces deux rapports distinguent les identités sociales de ces groupes. Lorsque les premiers sont dominés et peuvent se valoriser par leurs pratiques, les seconds sont dominants et le peuvent par une comparaison à d’autres villes qui se rapproche de l’idéologie de la ville-mondiale. Les enjeux identitaires des représentations et pratiques spatiales socialement intériorisées participeraient ainsi aux ségrégationsEver since the earliest forms of urbanism, cities have been shaped by ideological constructs that impact the everyday life of individuals and socio-spatial segregations. This PhD thesis focuses specifically on how positions in the social structure are objectified in the representations and everyday practice of urban space. Based on study of five different socio-spatial representations among University of Strasbourg staffers, it evidences a principle of structural homology between the cognitive, spatial and social dimensions of the individual-environment relationship. Some groups have a functional relationship to the city that reflects the complexity of the places they frequent. Conversely, others have an evaluative relationship that focuses on ‘emblematic’ places. These two relationships are markers of these groups’ social identities. Whereas the former are dominated and may seek to enhance their status through their practices, the latter are dominant and do so by making reference to the global city and comparing their city to others. The identity stakes of socially internalized spatial practices and representations ultimately contribute to segregation
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Albrecht, Birgit. "Novel representation and analysis of protein structure." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418641.
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Lee, Jamie. "The structure and representation of criminal actions." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266137.
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