Dissertations / Theses: 'Agnosie'

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Urbain, Pascal. "De l'indifférence à l'architecture." Aix-Marseille 1, 2010. http://theses.univ-amu.fr.lama.univ-amu.fr/2010AIX10126.pdf.

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Le public, quand il vaque à ses occupations, est souvent indifférent à l’architecture. Son indifférence est une conquête libératrice. L’architecte, quand il conçoit un projet, est souvent indifférent à l’existence de l’ouvrage. Son indifférence est nécessaire à la conception. Les indifférences conjointes du public et de l’architecte fondent leurs rapports contractuels
When people go about their business, they are frequently indifferent to architecture. Their indifference is a liberating conquest. At the moment of designing a project, the architect is often indifferent to the existence of the construction work. His indifference is necessary in the design. The joint indifference of people and the architect establish their contractual relationships

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Keïta, Luc Koenig Olivier Bedoin Nathalie. "Approche développementale et neuropsychologique de processus visuo-attentionnels traitements global et local selon la catégorie /." Lyon : Université Lumière Lyon 2, 2007. http://theses.univ-lyon2.fr/sdx/theses/lyon2/2007/keita_l.

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Martinaud, Olivier. "Reconnaissance visuelle et modules fonctionnels : étude neuropsychologique, anatomique et fonctionnelle." Paris 6, 2011. http://www.theses.fr/2011PA066355.

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Ce travail est consacré à l’étude du rôle du cortex occipitotemporal dans la reconnaissance visuelle des mots, ainsi que d’autres catégories d’objets : visages, lieux, outils. A cette fin, nous avons associé l’étude de patients cérébrolésés et l’imagerie cérébrale anatomique et fonctionnelle. Dans la 1ère étude en IRM anatomique et fonctionnelle, nous avons (a) établi que les lésions affectant une région précise du cortex occipitotemporal gauche (Visual Word Form Area, VWFA) sont critiques pour l’apparition d’une alexie pure, (b) corrélé d’autres types de troubles de la lecture avec des lésions définies du cortex ou de la substance blanche postérieure, (c) mis en évidence des voies de suppléances autorisant une compensation fonctionnelle. Dans la 2ème étude, nous avons (a) développé des tests comportementaux originaux, qui nous ont permis de montrer, dans une série consécutive de lésions du territoire des artères cérébrales postérieures, que les troubles agnosiques visuels sont bien plus fréquents qu’il n’est habituellement reconnu, (b) montré que si les corrélations anatomocliniques sont robustes dans le domaine de la lecture, elles le sont moins pour les autres catégories d’objets visuels, notamment du fait de la bilatéralité des régions impliquées (FFA, PPA, LOC) et de leur variabilité individuelle. La 3ème étude rapporte le cas exceptionnel d'une jeune patiente présentant une agnosie visuelle développementale majeure, contrastant avec la préservation des fonctions visuo-spatiales associées à la voie visuelle dorsale. Nous avons analysé ses déficits perceptifs, et tenté de les corréler avec la configuration des activations fonctionnelles et les anomalies focales de l’électrogenèse cérébrale. Conclusion : L’étude des patients cérébrolésés, enrichie par l’imagerie fonctionnelle, demeure indispensable à la démonstration des liens de causalité entre structures cérébrales et fonctions cognitives. Nous avons appliqué cette approche au domaine de la reconnaissance visuelle, apportant notamment une contribution majeure à la dissection anatomo-fonctionnelle des mécanismes cérébraux de la lecture. Nous avons également développé des outils directement utiles dans la prise en charge diagnostique des troubles neurovisuels acquis ou de développement

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Lallier, Marie. "Spécificités des troubles auditivo- et visuo-attentionnels dans la dyslexie développementale." Grenoble 2, 2009. http://www.theses.fr/2009GRE29025.

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Ce travail de thèse a pour objectif d'identifier les spécificités des troubles attentionnels dans les modalités visuelle et auditive dans le cadre de la dyslexie développementale. Ancré dans une approche multifactorielle de la dyslexie, ce travail évalue, à la fois en vision et en audition, l'indépendance de deux théories supposant un déficit attentionnel différent à l'origine du trouble dyslexique. Il a été en effet proposé que certaines dyslexies proviendraient d’un trouble phonologique causé par un déficit amodal du déplacement automatique de l'attention, alors que d'autres seraient la conséquence directe d'un déficit de l'attention simultanée dans la modalité visuelle et s'exprimeraient indépendamment de tout trouble phonologique (i. E. Trouble de l'empan visuo-attentionnel). Pour la première fois, des paradigmes expérimentaux similaires en modalité visuelle et auditive ont été utilisés chez les mêmes sujets afin d'évaluer leurs performances sur un ensemble d'épreuves permettant de contraster ces deux approches théoriques. Les résultats montrent que le trouble de la lecture est fortement relié à un déficit de l'attention séquentielle uniquement dans la modalité auditive, et remet en cause l'amodalité du déficit de l'attention séquentielle dans la dyslexie. Par ailleurs, nos résultats suggèrent que le traitement attentionnel séquentiel est lié au trouble phonologique et dissocié du trouble de l'attention visuelle simultanée chez les mêmes sujets dyslexiques. Enfin, nos résultats mettent en évidence une association entre le déficit de l'attention simultanée auditive et le déficit de l'empan visuo-attentionnel chez les mêmes sujets dyslexiques. Ce résultat suggère un trouble amodal de l'attention simultanée dans la dyslexie. Ainsi, le travail de thèse apporte de nouveaux éléments théoriques concernant les processus attentionnels déficitaires dans le trouble de lecture en tenant compte du profil cognitif des sujets et fournit des pistes concernant de futurs outils de diagnostic potentiels
This doctoral thesis aims at identifying the auditory and visual attentional specificities in the framework of developmental dyslexia. Grounded in an original multifactorial approach of the reading disorder, this work assesses in both visual and auditory domains the independency of two theoretical frameworks assuming different attentional causes leading to dyslexia. It has indeed been stated that some dyslexias would stem from a phonological deficit caused by an amodal sluggish attentional shifting, whereas others would stem from simultaneous attentional limitations in the visual modality (i. E. Visual attentional span deficit). For the first time, similar visual and auditory experimental paradigms are used in the same participants to assess their skills in a set of tasks contrasting the two theories. First, the results show that the reading disorder is strongly related to sequential attentional deficit in the auditory domain only, thus reconsidering the hypothesis of the amodal attentional sequential deficit in dyslexia. Moreover, our results suggest that phonological processing is linked to sequential attentional skills, and that sequential and simultaneous visual attentional disorders dissociate in developmental dyslexia. Finally, the auditory simultaneous attentional deficit is related to the visual attentional span disorder in the same dyslexic participants, thus suggesting the amodality of simultaneous attentional deficits in dyslexia. Overall, the results bring new theoretical insights about attentional disorders in dyslexia regarding the cognitive profile of participants, and give a framework to the design of future potential diagnostic tools

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Charnallet, Annik. "Reconnaissance visuelle d'objets et agnosie : revue critique de la littérature et étude de deux cas d'agnosie." Grenoble 2, 1993. http://www.theses.fr/1993GRE29015.

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Ce travail, qui se situe dans le courant de la neuropsychologie cognitive, etudie l'identification visuelle d'objet a partir de l'observation de deux cas d'agnosie visuelle. La partie theorique expose les deux grands types de modeles de l'identification : les modeles abstractifs classiques, inspires en grande partie de l'intelligence artificielle, et les modeles episodiques de la connaissances, jusqu'a present moins utilises que les premiers dans le domaine de la neuropsychologie. La partie experimentale consiste en l'etude de deux cas d'agnosie visuelle (un cas d'agnosie "integrative" et un cas d'agnosie "semantique) et confronte les donnees obtenues au differentes conceptions theoriques. Les interpretations proposees remettent en question les modeles abstractifs et tendent a valider les conceptions episodiques de l'identification visuelle d'objet
This thesis, which falls within the field of cognitive neuropsychology, studies visual object identification from the observation of two cases of visual agnosia. The litterature review presents the two main types of identification models : classical abstrative models, mostly inspired by artificial intelligences theories, and episodic models of knowledge which up to date have been much less used than the former in the field of neuropsychology. The experimental part consists in the study of two cases of visual agnosia (one "integrative" and the other "semantic") and confronts the data obtained abstractive models and tend to validate episodic conceptions of visual abject. Identification

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Lê, Sandra. "Neuropsychologie et neuro-imagerie fonctionnelle des troubles acquis de la perception visuelle : plasticité neuronale et adaptation comportementale." Toulouse 2, 2002. http://www.theses.fr/2002TOU20051.

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Cette étude a porté sur la neuropsychologie et la neuro-imagerie fonctionnelle d'un cas exceptionnel d'agnosie visuelle (SB) acquise dans l'enfance. Les lésions ont touché la voie ventrale (VV) bilatéralement, et la voie dorsale (VD) à droite. Les tests visuels ont montré que SB utilise une stratégie de reconnaissance visuelle au "trait par trait", et semble avoir préservé un module de traitement implicite des visages. Une expérience de détection de formes en IRM a montré que SB utilise des stratégies visuelles impliquant la VD gauche pouvant pallier une quasi-abence de la VV. Ces observations nous ont montré la nécessité de prolonger l'étude du "rôle" des voies ventrale et dorsale dans la perception visuelle. Enfin, une étude en neuro-imagerie sur la perception visuelle résiduelle du mouvement chez des hémianopsiques a montré que l'activité des aires occipitales latérales, mais pas celle du cortex clcarin, est nécessaire pour la discrimination du mouvement chez ces patients
Through an exceptional case of visual agnosia (SB) acquired in childhood, this thesis constitutes a neuropsychological and neuro-imaging approach to visual perception. Lesions affected the ventral stream (VS) bilaterally and the right dorsal stream (DS). Visual tests showed that SB uses a "feature by feature" visual recognition strategy. Two experiments revealed that SB may have retained a spared module for implicit face processing. A visual form detection experiment in fMRI showed that SB may have developed visual stategies involving the left DS and palliating for the quasi-absence of the VS. These observations showed us the necessity to further investigate the "role" palyed by the ventral and dorsal streams in visual perception. Finally, a neuro-imaging study was conducted on the visual residual discrimination of motion in hemianopes and showed that activation in the lateral occipital areas, but not in the calcarine cortex, is necessary for motion discrimination in these patients

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Guibert, Clément de. "Troubles dans le langage de l'éthique et de la pulsion : de la clinique psychiatrique à l'anthropologie clinique." Rennes 2, 1998. http://www.theses.fr/1997REN20032.

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Dans la perspective fondée par J. Gagnepain sous l'appellation d'anthropologie clinique, le langage est aborde en tant que lieu d'une déconstruction de déterminismes analogues. Au déterminisme du signe qui spécifie le langage proprement dit, s'adjoignent l'outil, la personne et la norme qui le font respectivement écriture, langue et discours. Plus précisément ici, dans le signe, ce travail veut contribuer a formaliser la fonction gnosique, capacité naturelle de cognition perceptive dont le rapport dialectique avec l'analyse grammaticale abstraite fait l'ambiguïté du langage humain. Concernant la norme, il s'agit, analogiquement a la gnosie, de préciser la fonction boulique, capacité naturelle de pulsion dont le rapport avec la mesure éthique abstraite fait l'ambivalence de la volonté humaine. Théoriquement, nous présentons le modèle hypothétique du langage, conçu comme dialectique de la gnosie et de la grammaticalité ; le modèle est transpose au plan de la norme, conçue comme dialectique de la boulie et de la moralité. Epistémologiquement, est argumentée la nécessité d'une conception dialectique du langage, au-delà du formalisme et de l'empirisme, contre la conception classique et structuraliste de la référence en linguistique et la conception positiviste de la perception en psychologie. De la même façon est défendue une conception dialectique de la volonté, contre le formalisme psychanalytique et l'économisme psychologique. Cliniquement, nous défendons une méthode ou se confrontent inséparablement modèle et nosographie, ou il s'agit de formaliser dans la pathologie, a contrario révélatrice du normal, la cohérence et la cohésion spécifiques des syndromes. Nous nous fondons donc ici sur l'expérimentation de l'agnosie, pathologie (neurologique) de la perception, pour laquelle nous argumentons la prévalence d'une analyse grammaticale privée de discernement référentiel ; y sont opposées systématiquement l'aphasie et la schizophasie du bégaiement. Analogiquement, est présentée l'observation de deux patientes dites maniaco-dépressives en psychiatrie pour lesquelles est défendue l'hypothèse de l'aboulie, opposée aux psychopathies et aux névroses ; nous y argumentons l'existence d'une mesure éthique sans préférence pulsionnelle
In the perspective based on by J. Gagnepain and known under the term of clinical anthropology, language is understood like the place of a deconstruction of analogic determinism. At the determinism of sign that specifies the language proper, appoint the << outil >>, the << personne >> and the << norme >> that make it respectively writing, speaking and speech. Particularly, this work contributes to explain, about the sign, the gnosical function, natural ability to perceptive cognition which relation to grammaticality makes the ambiguity of human language. Similarly, about the norm, we took interest in what we name aboulia that is natural ability to drive (or wish), and which relation to morality makes the ambivalence of human will. Theoretically, we present the hypothetical model of language, understood like dialectic of gnosia and grammaticality ; the model is transposed to the norm, understood like dialectic of drive (or interest) and morality. Epistemologically, we argue the necessity of dialectic conception of language, against classical conception of the reference in linguistic and against the conception of perception in psychology ; in the same order, we argue the interest of dialectic conception of will, between wish (or drive) and ethic moderation, against structuralism in psychoanalysis and economism in psychology. Clinically, we defend a method where model and nosographia are inseparably compared, and where it is matter of coherence and cohesion's syndromes. We based here on the investigation of agnosia, neurological disorder of perception, that we put up against aphasia (disorder of grammatical analysis) and schizophasia of stuttering ; for agnosia, we argue dominance of grammatical analysis, without cognitive perception. Similarly, we present an investigation of two so-called maniac-depressive patients in psychiatry, for which we suppose an aboulia, put up against caracteriels, addiction and neurosis ; about aboulia, we argue dominance of ethic moderation, without wish preference (or comportemental direction)

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Teixeira, Ferreira Carla. "Architecture anatomo-fonctionnelle de la connaissance des objets : apport de la neuropsychologie clinique." Lyon 1, 1997. http://www.theses.fr/1997LYO1T111.

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Benelhadj, Mustapha. "Perception visuelle de l'action : approche neuropsychologique." Aix-Marseille 2, 2003. http://www.theses.fr/2003AIX20699.

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Ce travail porte sur l'approche neuropsychologique des substrats neuronaux de la perception visuelle des actions. La première partie est consacrée à une revue des connaissances actuelles sur le système visuel, en particulier de ceux issus de la neurophysiologie. Ces travaux soulignent l'existence d'une ségrégation anatomique et fonctionnelle entre deux voies corticales visuelles, la voie ventrale, formée des cortex occipito-temporaux internes, impliquée essentiellement dans la reconnaissance visuelle des objets (" what ") et la voie dorsale, constituée de cortex occipito-temporaux externes et de cortex occipito-pariétaux, et dont la fonction serait dévolue aux traitements spatiaux et visuo-moteurs (" where " et " how "). Nous nous sommes interrogés sur les contributions respectives de ces deux voies dans la perception, l'identification et le maintien de représentations d'actions présentées visuellement. La première expérience est consacrée à l'étude des capacités de discrimination visuelle de deux actions de locomotion humaine - marcher et courir - présentées sous la forme de pattern de points (" biological motion ") sous des angles de vue canoniques et non canoniques. Les sujets sains sont capables de discriminer ces deux actions, même quand certains indices de forme (détérioration de la symétrie des membres) sont escamotés. La présence de mouvement permet aux sujets d'organiser de manière cohérente la perception de ces patterns de points complexes en actions finalisées de locomotion humaine. La suppression du mouvement rend l'interprétation de ces patterns difficile mais n'abolit pas les capacités de discrimination visuelle de ces actions, ce qui implique que ces patterns contiennent des informations " suggestives " de mouvement. Nous avons ensuite étudié les performances de deux patients cérébro-lésés JR et AK dans des tâches de détection de cibles statiques, de discrimination de direction de cibles en mouvement linéaire et de mouvement cohérent, ainsi que dans des tâches d'identification d'objets animés et de " biological motion ". Une double dissociation concernant l'identification de formes et la perception visuelle du mouvement est retrouvée entre JR, qui présente une agnosie visuelle aperceptive secondaire à des lésions étendues des régions occipito-temporales et AK qui présente une akinétopsie en relation avec des lésions dorsales. Par contre nos résultats suggèrent que l'intégrité des deux voies visuelles - ventrale et dorsale - est nécessaire à la reconnaissance de stimuli combinant des informations de formes et de mouvement. La troisième section expérimentale concerne l'étude des performances de sujets sains, de celles de JR et de X, patient affecté d'une pathologie (dégénérescence cortico-basale) affectant les praxies, dans une tâche d'identification de photographies de gestes transitifs. Ces résultats montrent que chez le sujet sain et chez JR, la forme du geste prend le pas sur l'identité de l'objet, alors que le contraire est retrouvé chez X. La dernière partie est consacrée à l'étude de l'imagerie visuelle de JR. Nos données retrouvent une préservation relative de l'imagerie visuelle de JR pour le mouvement, et sont en accord avec la conception selon laquelle il existe un substrat neuronal commun pour la perception visuelle et l'imagerie mentale
This work concerns neuropsychological approach of neuronal substrates of visual perception of actions. In the first part, we present current views on the visual system, especially those obtained from neurophysiological studies. These studies have underlined the anatomical and functional segregation between two visual cortical pathways: the " ventral pathway " (system of " what ") and the " dorsal pathway " (system of " where " and " how "). Our work is devoted to the study of respective contributions of each visual pathway to perception, identification and mental representation of actions, which are visually presented [. . . ]

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Van, Assche Mitsouko. "Rôle des processus de groupement automatiques et contrôlés dans les troubles de l’organisation visuo-perceptive dans la schizophrénie : approche en psychologie expérimentale et en imagerie par résonance magnétique fonctionnelle." Strasbourg, 2010. https://publication-theses.unistra.fr/public/theses_doctorat/2010/VAN_ASSCHE_Mitsouko_2010.pdf.

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Les capacités d’organisation visuo-perceptive sont altérées dans la schizophrénie. Les mécanismes précis de ces altérations demeurent toutefois mal connus. L’objectif de cette thèse est d’identifier l’origine de ces déficits, à l’aide d’outils issus de la psychologie cognitive et de l’IRMf. Une première étude a montré une difficulté spécifique chez les patients pour re-grouper mentalement deux figures appartenant à des groupes perceptifs différents. Leurs capacités à comparer deux figures appartenant à un même groupe perceptif (groupement automatique) étaient par contre préservée. Nous avons formulé l’hypothèse d’un déficit des processus contrôlés, ceux-ci étant nécessaires pour pouvoir re-grouper des informations séparées. Une deuxième étude chez le sujet sain a révélé que le re-groupement mental et le groupement automatique donnaient lieu à des représentations de nature qualitativement différentes. L’objectif de la troisième étude a été de tester si les déficits d’organisation chez les patients pouvaient s’expliquer en termes d’une difficulté fondamentale à re-grouper mentalement des informations séparées, ou à construire une représentation intégrée de l’environnement qui inclut des groupements de nature différente. Les résultats convergent vers cette dernière hypothèse
Visuo-perceptual organization is impaired in schizophrenia. However, the precise mechanisms leading to this deficit are not clear. The present work aimed at understanding the basis of this deficit, with methods issued from cognitive psychology and fMRI. A first study has shown that patients are impaired at mentally comparing two figures which are part of different perceptual groups. However, patients showed preserved abilities to compare two figures belonging to the same perceptual group (automatic grouping). We have proposed that the deficits reflect impaired controlled processes, preventing patients from re-grouping information that is initially segregated. A second study in healthy subjects has shown that mental re-grouping and automatic grouping lead to qualitatively distinct representations. The goal of the third study was to test whether patients’ deficits would best be described in terms of a basic difficulty to establish links between segregated figures, or in terms of a difficulty to build a coherent representation of the visual environment, integrating qualitatively different groupings. The data favour the latter hypothesis

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Keïta, Luc. "Approche développementale et neuropsychologique de processus visuo-attentionnels : traitements global et local selon la catégorie." Lyon 2, 2007. http://theses.univ-lyon2.fr/documents/lyon2/2007/keita_l.

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Notre thèse porte sur l'implication de processus attentionnels dans les traitements global et local de stimuli visuels complexes et s'appuie sur des données comportementales issues d'expériences présentant des stimuli hiérarchisés en champ visuel divisé. Nous montrons l'influence d’un processus de haut niveau, qui module l'implication de mécanismes latéralisés selon leur spécialisation pour l'analyse globale ou locale, mais aussi pour des catégories (Lettre / Dessin d'objet). Nous étudions aussi le processus attentionnel permettant d'alterner le traitement des détails et de la forme globale et montrons qu'il s’appuie sur plusieurs opérations : l’une d'elles, la désélection du mode d'analyse inapproprié, s'appuie sur un mécanisme d'inhibition qui se distingue par une dominance de l'hémisphère droit. La sélection d'un niveau est enfin étudiée à travers les effets d'interférence induits par l'information concurrente située au niveau devant être inhibé. Après le Chapitre I proposant 8 expériences sur ces processus auprès de jeunes adultes, le Chapitre II étudie leur mise en place avec 2 expériences chez des enfants de 6 à 10 ans. Les 2 expériences du Chapitre III isolent enfin des anomalies spécifiques à des types de dyslexie différents. Les enfants atteints de dyslexie avec des troubles phonologiques majeurs présentent une latéralisation hémisphérique fonctionnelle anormale pour traiter les catégories Lettre et Dessin d'objet, alors qu'un déficit spécifique du mécanisme d'inhibition d'information issue du niveau local caractérise les enfants dyslexiques sans trouble phonologique. La spécificité de ces déficits conforte l'hypothèse d’un trouble des représentations linguistiques dans le premier type de dyslexie, et l'existence d'un autre type de dyslexie, caractérisé par des troubles de l'attention visuo-spatiale dont cette recherche contribue à préciser la nature
Our doctoral dissertation concerns the involvement of neural mechanisms of attention on global and local processing and is based upon behavioral data from experimentation presenting hierarchically organized stimuli in divided visual fields. We have shown the influence of high-level processing which modulates the involvement of lateralized mechanisms according to their specialization for global or local analysis as well as for categories (Letter/Object). We have also studied the neural mechanism that allows switching attention between processing details and the global form, which we have shown it to rely on several mechanisms: one of which, unselecting the inappropriate analysis mode, relies on an inhibition mechanism that is differentiated by its right hemisphere dominance. The selection of a processing level was then studied through the effects of interference inferred by concurrent information situated on a level needing to be inhibited. Chapter I presents 8 experiments on these mechanisms for young adults, Chapter II studies their implementation with 2 experiments among children from 6 to 10 years old. The 2 experiments from Chapter III isolate specific anomalies in different types of dyslexia. Children suffering from dyslexia with major phonological disorders present an abnormal functional hemispheric lateralization for processing the Letter and Object categories, whereas a specific deficit of an inhibition mechanism for information on a local level characterize dyslexic children without phonological disorders. The specificity of these deficits reinforces the hypothesis of a linguistic representation disorder in the first type of dyslexia, and the existence of another type of dyslexia characterized by visuo-spatial attention difficulties

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Suchocka-Chainay, Hanna. "Asymétrie entre les catégories naturelles et les artefacts dans les tâches de dénomination et de reconnaissance visuelle : la pathologie Alzheimer et le fonctionnement normal." Lyon 1, 1998. http://www.theses.fr/1998LYO1T077.

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Schnider, Armin. "Agnosien - Störungen des Erkennens /." [S.l.] : [s.n.], 1996. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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Whitney, Hannah L. "Object agnosia and face processing." Thesis, University of Southampton, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.548326.

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Decter, Matthew. "Visual object processing in a case of category-specific agnosia." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60486.

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A single case study of a brain damaged patient with a category-specific visual agnosia for living things is described. The patient's deficit is manifested as a profound inability to identify, label or classify biological visual objects at the basic level. Most similar cases in the literature have been described as due to damage to a pre-categorical structural description system. However, all these cases also displayed content-specific impairments in activating knowledge from words. ELM's ability to activate basic-level knowledge from pictures and words is investigated using accuracy-based and chronometric measures. The pattern of ELM's category-specific visual agnosia is concomitant with his failure to show priming and typicality effects for words. This suggests that ELM's deficit resides within the semantic memory system. Tests of the integrity of structural descriptions reveal that this patient retains implicit access to pre-categorical structural knowledge.

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Lacoste, Alexandre. "Agnostic Bayes." Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25671.

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Tableau d'honneur de la Faculté des études supérieures et postdorales, 2014-2015
L’apprentissage automatique correspond à la science de l’apprentissage à partir d’exemples. Des algorithmes basés sur cette approche sont aujourd’hui omniprésents. Bien qu’il y ait eu un progrès significatif, ce domaine présente des défis importants. Par exemple, simplement sélectionner la fonction qui correspond le mieux aux données observées n’offre aucune garantie statistiques sur les exemples qui n’ont pas encore été observées. Quelques théories sur l’apprentissage automatique offrent des façons d’aborder ce problème. Parmi ceux-ci, nous présentons la modélisation bayésienne de l’apprentissage automatique et l’approche PACbayésienne pour l’apprentissage automatique dans une vue unifiée pour mettre en évidence d’importantes similarités. Le résultat de cette analyse suggère que de considérer les réponses de l’ensemble des modèles plutôt qu’un seul correspond à un des éléments-clés pour obtenir une bonne performance de généralisation. Malheureusement, cette approche vient avec un coût de calcul élevé, et trouver de bonnes approximations est un sujet de recherche actif. Dans cette thèse, nous présentons une approche novatrice qui peut être appliquée avec un faible coût de calcul sur un large éventail de configurations d’apprentissage automatique. Pour atteindre cet objectif, nous appliquons la théorie de Bayes d’une manière différente de ce qui est conventionnellement fait pour l’apprentissage automatique. Spécifiquement, au lieu de chercher le vrai modèle à l’origine des données observées, nous cherchons le meilleur modèle selon une métrique donnée. Même si cette différence semble subtile, dans cette approche, nous ne faisons pas la supposition que le vrai modèle appartient à l’ensemble de modèles explorés. Par conséquent, nous disons que nous sommes agnostiques. Plusieurs expérimentations montrent un gain de généralisation significatif en utilisant cette approche d’ensemble de modèles durant la phase de validation croisée. De plus, cet algorithme est simple à programmer et n’ajoute pas un coût de calcul significatif à la recherche d’hyperparamètres conventionnels. Finalement, cet outil probabiliste peut également être utilisé comme un test statistique pour évaluer la qualité des algorithmes sur plusieurs ensembles de données d’apprentissage.
Machine learning is the science of learning from examples. Algorithms based on this approach are now ubiquitous. While there has been significant progress, this field presents important challenges. Namely, simply selecting the function that best fits the observed data was shown to have no statistical guarantee on the examples that have not yet been observed. There are a few learning theories that suggest how to address this problem. Among these, we present the Bayesian modeling of machine learning and the PAC-Bayesian approach to machine learning in a unified view to highlight important similarities. The outcome of this analysis suggests that model averaging is one of the key elements to obtain a good generalization performance. Specifically, one should perform predictions based on the outcome of every model instead of simply the one that best fits the observed data. Unfortunately, this approach comes with a high computational cost problem, and finding good approximations is the subject of active research. In this thesis, we present an innovative approach that can be applied with a low computational cost on a wide range of machine learning setups. In order to achieve this, we apply the Bayes’ theory in a different way than what is conventionally done for machine learning. Specifically, instead of searching for the true model at the origin of the observed data, we search for the best model according to a given metric. While the difference seems subtle, in this approach, we do not assume that the true model belongs to the set of explored model. Hence, we say that we are agnostic. An extensive experimental setup shows a significant generalization performance gain when using this model averaging approach during the cross-validation phase. Moreover, this simple algorithm does not add a significant computational cost to the conventional search of hyperparameters. Finally, this probabilistic tool can also be used as a statistical significance test to evaluate the quality of learning algorithms on multiple datasets.

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Poliva, Oren. "Neuroanatomical and perceptual deficits in auditory agnosia : a study of an auditory agnosia patient with inferior colliculus damage." Thesis, Bangor University, 2014. https://research.bangor.ac.uk/portal/en/theses/neuroanatomical-and-perceptual-deficits-in-auditory-agnosia--a-study-of-an-auditory-agnosia-patient-with-inferior-colliculus-damage(d6c753aa-4c94-4d45-b639-92767ead661e).html.

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Auditory agnosia is a rare disorder in which individuals lose the ability to understand sounds. In this thesis, I examine an auditory agnosia patient with brainstem damage, but intact cortex. The patient was severely impaired when instructed to type the names of sounds. The patient, however, was only mildly impaired when instructed to choose the correct sound out of four written alternatives, which implies partial auditory perception. In two fMRI scans, conducted a year apart, passive listening to sounds resulted with a unique activation pattern in her auditory cortices. In particular, her anterior primary and associative auditory fields were much less responsive to sounds than more posterior primary and associative auditory fields. The functional dissociation between these regions suggests connections between the anterior primary and associative regions, and between the posterior primary and associative regions. Hitherto, these connections were only reported in monkeys. An EEG study that examined mismatch negativity for frequency, duration, and intensity of sounds, demonstrated that the patient’s ability of detecting changes to frequency and duration of sounds is bilaterally impaired, whereas the detection of changes to sound’s intensity is impaired in the left hemisphere but intact in the right hemisphere. Behavioral studies also show that the patient’s auditory perceptual deficit is partially due to impaired perception of the duration of sounds. For instance, when the patient heard two subsequent clicks, she was impaired at discriminating these sounds by the duration of their intervening interval. In a spoken word discrimination task, she was also impaired at discriminating words that could only be distinguished by their temporal properties (voice onset-time). Based on these findings, I argue that the patient experiences auditory agnosia be- cause the brain stem injury prevents the transmission of critical auditory information to the auditory cortex. As a result of this absence, the auditory fields responsible for sound recognition, the anterior auditory fields, are not recruited. In a dichotic listening task, the patient extinguished sounds presented to the right ear, and in a sound localization task she perceived sounds as emerging from the left auditory hemi-field. Given cumulative evidence that associates the posterior auditory cortex with sound localization and phonological-acoustic analysis of verbal material from the contra-lateral hemi-field, the patient’s performance in these tasks suggest that her spared auditory abilities is due to processing in her right posterior auditory cortex. This role of the patient’s right posterior auditory cortex is consistent with both the fMRI study, in which the right posterior auditory cortex was consistently responsive to sounds, and the EEG study, in which detection of changes to sound intensity was restricted to the right hemisphere.

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Daar, Waqas. "Distribution Agnostic Video Server." Thesis, KTH, School of Information and Communication Technology (ICT), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-24269.

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With the advances of network and communication technology, real time audio and video streaming services are becoming progressively popular over the Internet. In order to enable universal access of multimedia streaming content and thus the desired end-to-end QoS, it is very desirable to design a video server. A video server, that can dynamically coupled to dierent streaming engines and deployed in a test bed for conducting dierent streaming experiments.

In this thesis we present the design of a video server that implement an agnostic" experiments using dierent engines. Proposed video server is also deployed in a test bed for evaluating dierent performance measurement parameters like CPU load, memory utilization etc. The results of test bed also support our proposed idea and unfold many opportunities for the research community to perform dierent multimedia streaming experiments with proposed video server. "engine-abstraction that will help to automate and repeat deterministic streaming

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Hamdy, Ronald C., Amber Kinser, Jennifer E. Culp, Tracey Kendall-Wilson, Audrey Depelteau, Rebecca Copeland, and Kathleen Whalen. "Agnosia Interferes With Daily Hygiene in Patients With Dementia." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/2735.

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Patients with dementia, particularly Alzheimer’s disease, may not recognize that their clothes are dirty. They may see the food stains and discoloration of the clothes and yet because of their agnosia are unable to integrate these observations and deduce that their clothes are dirty and need to be changed. They will, therefore, resist attempts to get them to change clothes, especially if these clothes happen to be their favorite ones. This often causes caregivers to become frustrated, especially, if it represents a change in the patient’s previous habits of only wearing clean clothes. In this case study, we present a 72-year-old woman with moderate Alzheimer’s disease who lives with her daughter, who adamantly refuses to change the clothes she has been wearing for a few days and which are now clearly dirty. We report the interaction, highlight what went wrong in the patient–daughter interaction, and discuss how the catastrophic ending could have been avoided or averted.

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Osei, Raymond N. "The case for agnostic materialism." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264299.

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Schiavetto, Alessandra. "Plasticity and compensation in a childhood case of visual agnosia." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ26734.pdf.

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Duval, Céline. "Pain perception in schizophrenia, and relationships between emotion and visual organization : is emotion flattened in patients, and how does it affect cognition?" Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAJ052/document.

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La schizophrénie touche 1% de la population et comprend des symptômes positifs (hallucinations) et négatifs (affect émoussé), mais aussi des troubles cognitifs. Ici nous présentons deux expériences qui explorent l’interaction entre cognition, douleur et émotion chez les patients et les sujets sains. La première étude montre que des images émotionnelles peuvent détourner l’attention jusqu’à renverser les effets de groupement automatique. Cet effet est présent chez les patients comme chez les témoins. La deuxième étude est centrée sur la perception de la douleur en prenant en compte les différents mécanismes sollicités, dont le traitement émotionnel. Nos résultats, et notamment une P50 élevée chez les patients après la stimulation douloureuse montrent une hypersensibilité à un niveau très précoce. Les deux études montrent que les patients sont plus sensibles aux stimuli émotionnels et douloureux que ce que l’on pensait, ce qui devrait être pris en compte lors de leur prise en charge
Schizophrenia is a severe mental illness affecting 1% of the population, and comprises positive (hallucinations) and negative symptoms (blunted affect), but also cognitive deficits. Here we describe two distinct studies which address the question of how emotion and cognition interact, in healthy subjects and in schizophrenia. In the first study we created a paradigm that shows how emotional stimuli distract subjects and thus interfere during the organization of visual stimuli. The effect is the same in patients and healthy controls.In our second study we explored pain perception by taking into account different mechanisms, and especially emotion processing. The results show that patients are more sensitive to pain than healthy controls as they present an elevated P50 which indicates an alteration at an early stage of processing. Both studies reveal that patients are more sensitive as previously thought which has to be considered when dealing with patients in hospitals and everyday life

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Lecerf, Jason. "Designing language-agnostic code transformation engines." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I077.

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Les transformations automatiques de code apparaissent dans diverses situations, les refactorings, les migrations inter-langages ou encore la spécialisation de code. Les moteurs supportant ces transformations cherchent dans le code source les occurrences de motifs spécifiés par l’utilisateur, puis les réécrivent grâce à une transformation. Cette transformation peut soit modifier les occurrences elles-mêmes, des éléments de la représentation intermédiaire (IR) du langage, en nouveaux éléments ou réécrire leur code source. Nous nous concentrons sur la réécriture de code source qui offre une meilleure flexibilité grâce à des transformations arbitraires particulièrement utiles à la migration et à la spécialisation de code. Les motifs sont divisés en deux catégories : les motifs explicites et syntaxiques. Les premiers demandent que l’utilisateur connaisse l’IR du langage, un effort d’apprentissage non négligeable. Les seconds demandent seulement de connaître la syntaxe du langage et non son IR, mais requièrent un effort d’implémentation supplémentaire pour les back-ends de langage du moteur. Tandis que les experts en langage connaissent l’IR et la syntaxe du langage, les autres utilisateurs connaissent seulement la syntaxe. Nous proposons un moteur de reconnaissance de motifs offrant une représentation hybride des motifs : les motifs peuvent être à la fois explicites et syntaxiques. Par défaut, le moteur se rabat sur un fonctionnement syntaxique, car la barrière à l’entrée est plus basse. Pour pallier au coup d’implémentation des back-ends de langage pour la reconnaissance syntaxique, nous prenons une approche générative. Le moteur de reconnaissance hybride est couplé avec un moteur de génération d’analyseurs syntaxiques. Ce dernier génère des analyseurs syntaxiques LR généralisés (GLR) capables d’analyser non seulement le code source à réécrire, mais également le motif à reconnaitre. L’implémenteur du back-end de langage n’a alors qu’à ajouter une ligne à la grammaire pour avoir accès au moteur de reconnaissance de motifs pour ce langage. L’approche est basée sur des analyseurs syntaxiques GLR pouvant se dupliquer et traquant ses sous-analyseurs. Ces implémentations particulières de GLR ne passent pas à l’échelle quand trop de duplications sont nécessaires pour gérer les ambiguïtés et notre approche ajoute de la duplication. Pour éviter une explosion du temps d’exécution, nos analyseurs syntaxiques FGLR fusionnent plus régulièrement et permettent une désambiguïsation à la volée pendant l’analyse via des effets de bord
Code transformations are needed in various cases: refactorings, migrations, code specialization, and so on. Code transformation engines work by finding a pattern in the source code and rewriting its occurrences according to the transformation. The transformation either rewrites the occurrences, elements of the intermediate representation (IR) of the language, into new elements or directly rewrites the source code. In this work, we focused on source rewriting since it offers more flexibility through arbitrary transformations, especially for migrations and specializations. Matching patterns come in two different flavors, explicit and syntactic. The former requires the user to know the IR of the language, a heavy knowledge burden. The latter only relies on the syntax of the matched language and not its IR, but requires significantly more work to implement the language back-ends. Language experts tend to know the IR and the syntax of a language, while other users know only the syntax. We propose a pattern matching engine offering a hybrid pattern representation: both explicit and syntactic matching are available in the same pattern. The engine always defaults to syntactic as it is the lowest barrier to entry for patterns. To counterbalance the implementation cost of language back-ends for syntactic pattern matching, we take a generative approach. We combine the hybrid pattern matching engine with a parser generator. The parser generator generates generalized LR (GLR) parsers capable of not only parsing the source but also the hybrid pattern. The back-end implementer only needs to add one line to the grammar of the language to activate the pattern matching engine. This approach to pattern matching requires GLR parsers capable of forking and keeping track of each individual fork. These GLR implementations suffer the more forking is done to handle ambiguities and patterns require even more forking. To prevent an explosion, our Fibered-GLR parsers merge more often and allow for classic disambiguation during the parse through side-effects

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Ruffolo, Jessica Somerville. "Visuoconstructional impairement : what are we assessing, and how are we assessing it? /." View online ; access limited to URI, 2004. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3147803.

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Norozi, Muhammad Ali. "The Contextual Features in Schema-Agnostic Environment." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24361.

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Relevance scoring and estimation deals with both finding the relevant set of answers and ordering them according to the degree of their relevance to the user-intent. The traditional information retrieval (IR) systems successfully find and order the relevant documents and leave them to the users, who then have to locate the relevant information embedded somewhere within the document. In contrast, estimating relevance in semi-structured retrieval means not only retrieving and ordering the relevant documents but also locating the relevant information within the document as well. When it comes to semi-structured retrieval, the traditional IR style retrieval is simply insufficient. The main focus of this thesis is estimating relevance in a schema-agnostic environment. Here, “schema-agnostic” means that the schema or the structure exists explicitly within the documents but the user does not or need not know that schema. In such an environment, the structure is generally defined loosely, which means: (a) it can evolve over time, (b) it can constitute a large part of the data, and (c) it might exist seamlessly within the document. The natural question that comes into mind is, why is such a structure there at all? The structure in a schemaagnostic environment is there to be used by retrieval systems for several useful tasks. This thesis is about unveiling the capabilities of the structural constructs within semi-structured documents in schema-agnostic settings. Structural constructs can form what we call the structural context of the relevant item. A structural context builds up the internal and external contextual features of a semi-structured document. These contextual features help with a series of tasks. The work presented in this thesis contributes towards understanding and utilizing the contextual features in the retrieval of focused information in schema-agnostic settings. During the course of this study we have identified, implemented and experimented with several intuitive types of contextual features in semi-structured retrieval settings. Contextualization is the generic process of utilizing features in the structural context of the retrievable units in relevance scoring. The proposed retrieval approaches, based mainly on contextual features, exhibited notable improvements in retrieval effectiveness, during empirical analyses. The evaluations and empirical analyses are performed in several tasks, spread across different phases of this study. The tasks are performed by looking at different aspects and challenges of the semi-structured retrieval domain. The following tasks are performed at different phases of this study: ad-hoc tasks, granulation tasks, and standard tasks offered by INitiative for the Evaluation of Xml retrieval (INEX). The contributions of this thesis are also grouped by these tasks.

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Yang, Jean Ph D. Massachusetts Institute of Technology. "Preventing information leaks with policy-agnostic programming." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101468.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged student-submitted from PDF version of thesis.
Includes bibliographical references (pages 103-115).
As a solution to the problem of information leaks, I propose a policy-agnostic programming paradigm that enforces security and privacy policies by construction. I present the implementation of this paradigm in a new language, Jeeves, that automatically enforces information flow policies describing how sensitive values may flow through computations. In Jeeves, the programmer specifies expressive information flow policies separately from other functionality and relies on the language runtime to customize program behavior based on the policies. Jeeves allows programmers to implement information flow policies once instead of as repeated checks and filters across the program. To provide strong guarantees about Jeeves programs, I present a formalization of the dynamic semantics of Jeeves, define non-interference and policy compliance properties, and provide proofs that Jeeves enforces these properties. To demonstrate the practical feasibility of policy-agnostic programming, I present Jacqueline, a web framework built on Jeeves that enforces policies in database-backed web applications. I provide a formalization of Jacqueline as an extension of Jeeves to include relational operators and proofs that this preserves the policy compliance guarantees. Jacqueline enforces information flow policies end-to-end and runs using an unmodified Python interpreter and SQL database. I show, through several case studies, that Jacqueline reduces the amount of policy code required while incurring limited overheads
by Jean Yang.
Ph. D.

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Byun, Jiwon. "Thomas Henry Huxley's agnostic philosophy of science." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62665.

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This dissertation examines Thomas Henry Huxley’s notion of agnosticism and its bearings on his conception of science. Although agnosticism is commonly regarded as a position that recognizes the limits of human knowledge, Huxley – who coined the term “agnostic” – characterized it as more than a theory of ignorance or limits. I argue that Huxley intended his agnosticism to be a guide to knowledge that can work regardless of our ignorance or limits. To this end, I draw attention to Huxley’s less famous philosophical works. I examine his discussions of Descartes to show that he had an epistemological project and to clarify the structure of agnosticism; I analyze his Hume to illuminate the reasoning behind his claim that verification is the only justificatory method and to highlight his reasons for situating agnosticism within what he called “modern critical philosophy”; I investigate his other essays to argue that his agnosticism concerns a claim to knowledge and should not be understood as ethics of belief. Based on his epistemological inquiry, Huxley offered a quick guide to knowledge, consisting of an account of legitimate evidence and an ethics of knowing: agnosticism. It can be summarized as follows. Propositions concerning anything beyond phenomena lack evidential value; verified propositions have evidential value; if one wishes to make a claim about the knowledge status of a proposition, one should evaluate the evidence and be honest about the result without further pretension. Huxley discussed the realm of ignorance to show its lack of justificatory value. The signature remark of Huxleyan agnostics is “Show me evidence,” rather than “I don’t know.” This interpretation undermines the widely accepted view that Huxley’s endorsement of agnosticism poses philosophical obstacles to his larger project of promoting science in Victorian society. His intention behind agnosticism was to establish and maintain epistemic merit of science without any unknowable, metaphysical or theological, apparatus. Science is the practice of agnosticism, and for this reason, our best way to knowledge. Our understandings of his life-long project and of the growth of science’s autonomy during the 19th century would remain incomplete without due appreciation of this notion of agnosticism.
Arts, Faculty of
Philosophy, Department of
Graduate

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Murphy, Eoin. "Wavelength agnostic WDM strategies for avionic telecommunications." Thesis, University of Strathclyde, 2015. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=26018.

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This thesis investigates the possibility of deploying a fibre optic network on aircraft; the network should provide 1.25 Gbps links between various end nodes throughout the aircraft. Particular attention has been paid to Wavelength Division Multiplexing (WDM) in Passive Optical Networks (PONs) and how the network is affected by the harsh environment found on aircraft. The harsh environment presents a particular challenge with respect to the operational temperature range. Over this range it is desirable to minimise any additional weight and power consumption associated with cooling network components. One technique assessed to implement WDM with minimised cooling is to use spectrum slicing to seed reflective semiconductor optical amplifiers which will be positioned at each end node. In theory these 'colourless' nodes will be temperature insensitive and capable of uncooled operation. This has been thoroughly studied and temperature ranges for uncooled operation identified with different end node components. Different cooling techniques have also been studied; one technique using a phase change material for passive cooling with no direct power consumption and the other using a thermo-electric cooler. The efficiencies of these techniques have been compared by analysing their impact on fuel burn. The use of distributed feedback lasers in a WDM PON has also been investigated and a novel method for reducing power consumption has been proposed. It has been predicted that this could reduce the power consumption of the optical transmitters in a realistic avionic environment by up to 20 %. This network has been compared to the network using the spectrum slicing technique with particular attention paid to the relative power consumptions. The merits of both networks in the avionic context have been discussed and different scenarios where each network is suitable have been identified.

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Duran, Marcos Henrique Coelho 1960. "Sindrome de Landau Kleffner aspectos clinicos, eletrencefalograficos e psicossociais : estudo de seguimento a longo prazo." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/311184.

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Orientador: Marilisa Mantovani Guerreiro
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-11T07:46:37Z (GMT). No. of bitstreams: 1 Duran_MarcosHenriqueCoelho_M.pdf: 1539945 bytes, checksum: 0b921a2ebbf75d5589e891134344723b (MD5) Previous issue date: 2008
Resumo: Objetivos: A Síndrome de Landau-Kleffner (SLK) é uma entidade rara, caracterizada por epilepsia e afasia. Ocorre em crianças com aquisição normal da linguagem, geralmente, entre 3 e 7 anos de idade. A evolução a longo prazo é controversa e pouco estudada. O presente estudo tem como objetivo verificar a evolução em uma série de sujeitos com diagnóstico de SLK, enfocando os aspectos clínicos, eletrencefalográficos, psicossociais e da qualidade de vida. Métodos: Trata-se de um estudo transversal. Entre novembro de 2006 e abril de 2007 foram entrevistados sete pacientes, todos do sexo masculino com idade variando entre oito e 27 anos. Todos os pacientes apresentaram afasia/agnosia auditiva verbal no início do quadro e apenas um paciente não apresentou crises epilépticas durante a evolução da SLK. Todos os pacientes apresentaram descargas epileptiformes interictais no início da SLK e dois pacientes apresentaram estado de mal elétrico do sono. Os pacientes e/ou pais foram entrevistados através de um questionário estruturado. Foram aplicados em todos os pacientes a Escala de Comportamento Adaptativo Vineland, a Escala de Conners para pais na versão longa revisada e o questionário a respeito de sua qualidade de vida (SF 36, ). Foi realizado em cada paciente eletrencefalograma interictal em vigília e sono prolongado. Resultados: O presente estudo revelou que dois pacientes continuavam a apresentar crises epilépticas. Um paciente apresentou remissão total da afasia/agnosia auditiva verbal e três pacientes apresentaram remissão parcial da afasia/agnosia auditiva, ao passo que três pacientes mantiveram a afasia/agnosia auditiva verbal. Quanto a qualidade de vida, apenas um paciente não apresentava limitações dentre os pacientes da presente série. Os demais pacientes apresentaram alguma limitação de sua qualidade de vida, sendo a afasia/agnosia auditiva verbal o principal fator limitante no curso da SLK. Cinco pacientes apresentaram eletrencefalograma normal. Conclusões: O presente estudo revelou que a epilepsia e as alterações eletrencefalográficas tendem a desaparecer enquanto que a afasia/agnosia auditiva verbal tende a persistir na maioria dos pacientes. A idade de início não está correlacionada com o prognóstico. Os pacientes com SLK apresentam uma qualidade de vida comprometida, principalmente devido a afasia/agnosia auditiva verbal
Abstract: Purpose: Landau-Kleffner syndrome (LKS) is a rare entity characterized by epilepsy and aphasia. It occurs in previously normal children, usually between 3 and 7 years of age. The long-term outcome of the LKS is not completely clear. The aim of this study is to verify the long-term follow-up of a group of patients with LKS, focusing on clinical aspects, EEG, and quality of life. Methods: This was a transversal study. Between November 2006 and April 2007 seven patients with LKS were interviewed. They were seven males and were between eight and 27 years old. At onset, all patients had aphasia and verbal auditory agnosia and only one never had seizures. At onset, all patients had interictal epileptiform discharges, and two of them presented with ESES. Parents and/or patients were interviewed by one of the authors according to a structured questionnaire. The Vineland Adaptive Scales, the Conner¿s Rating Scales Revised and Short-Form Health Survey (SF 36) were used. Each patient had a prolonged interictal electroencephalographic recording. Results: The present investigation revealed that two patients still have seizures. One patient had total and three others had partial remission of language disturbance, while three patients still have aphasia and verbal auditory agnosia. Concerning quality of life, only one of our patients has a normal life nowadays. All six patients with some sort of limitation refer that aphasia/agnosia is the main difficulty of their lives. Five patients have normal EEG. Conclusions: The long-term follow-up of patients with LKS show that epilepsy and EEG abnormalities tend to disappear while language disturbance tend to persist in most of them. Age of onset does not correlate with the prognosis. Patients with LKS have an overall poor quality of life mostly due to language difficulties
Mestrado
Neurologia
Mestre em Ciências Médicas

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Giovanelli, Francesco. "Model Agnostic solution of CSPs with Deep Learning." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18633/.

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Negli ultimi anni, le tecniche di Deep Learning sono state notevolmente migliorate, permettendo di affrontare con successo numerosi problemi. Il Deep Learning ha un approccio sub-simbolico ai problemi, perciò non si rende necessario descrivere esplicitamente informazioni sulla struttura del problema per fare sì che questo possa essere affrontato con successo; l'idea è quindi di utilizzare reti neurali di Deep Learning per affrontare problemi con vincoli (CSPs), senza dover fare affidamento su conoscenza esplicita riguardo ai vincoli dei problemi. Chiamiamo questo approccio Model Agnostic; esso può rivelarsi molto utile se usato sui CSP, dal momento che è spesso difficile esprimerne tutti i dettagli: potrebbero esistere vincoli, o preferenze, che non sono menzionati esplicitamente, e che sono intuibili solamente dall'analisi di soluzioni precedenti del problema. In questi casi, un modello di Deep Learning in grado di apprendere la struttura del CSP potrebbe avere applicazioni pratiche rilevanti. In particolar modo, in questa tesi si è indagato sul fatto che una Deep Neural Network possa essere capace di risolvere il rompicapo delle 8 regine. Sono state create due diverse reti neurali, una rete Generatore e una rete Discriminatore, che hanno dovuto apprendere differenti caratteristiche del problema. La rete Generatore è stata addestrata per produrre un singolo assegnamento, in modo che questo sia globalmente consistente; la rete Discriminatore è stata invece addestrata a distinguere tra soluzioni ammissibili e non ammissibili, con l'idea che possa essere utilizzata come controllore dell'euristica. Infine, sono state combinate le due reti in un unico modello, chiamato Generative Adversarial Network (GAN), in modo che esse possano scambiarsi conoscenza riguardo al problema, con l'obiettivo di migliorare le prestazioni di entrambe.

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Kang, Kathryn Muriel. "Agnostic democracy : the decentred "I" of the 1990s." University of Sydney. Economics and Political Science, 2005. http://hdl.handle.net/2123/667.

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The thesis concerns the dynamics during the 1990s of political action by many groups of people, in what came to be called the movement of movements. The activists, who held that corporations were overstepping some mark, worked on alternative arrangements for self-rule. The thesis views the movement as micropolitics, using concepts devised by Deleuze and Guattari. It sets out particulars of the rhizomic make -up of the movement. A key point is that the movement trains participants in decentred organisation, which entails the forming of subject-groups as opposed to subjugated groups. The thesis records how the movement was shaped by earlier events in political action and thinking, especially from the 1960s on. The movement had previously been read as a push for absolute democracy (Hardt and Negri). The thesis shows that reading to have been incomplete: the movement is, in part, a push for agonistic democracy. More a practice than a form of rule, agonistic democracy is found where state power is bent on not moulding peoples into any unified polity. It is found where state power fosters conflicted-self-rule, so that every citizen may engage in the polity as a decentred "I". The thesis throws light on relations between the movement and the constitutionalist state. Part of the movement, while cynical about the existing form of state rule, wears a mask of obedience to constituted authority. When one upholds the fiction of legitimate rule, one can use the fiction as a restraint on the cynics-in-power. The play creates a shadow social contract, producing detente within the polity and within the �I.� The thesis also reports on a search in mainstream cinema for some expression of the movement's dynamics. The search leads to a cycle of thrillers, set in a nonfiction frame story about a coverup of gross abuse of state power.

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Kang, Kathryn M. "Agnostic democracy the decentred "I" of the 1990s /." Connect to full text, 2005. http://hdl.handle.net/2123/667.

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Thesis (Ph. D.)--University of Sydney, 2005.
Title from title screen (viewed 22 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Economics and Business. Includes bibliographical references. Also available in print form.

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Bober, James Marian. "The late agnostic : William Bronk as religious poet." Thesis, University of Leicester, 2014. http://hdl.handle.net/2381/29249.

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This thesis examines the poetry of William Bronk (1918-99). Through close readings of individual texts and broader thematic explorations it demonstrates that Bronk can and should be viewed as a religious poet. In agreement with previous scholars, via original thematic and formal comparisons of the poets’ work, it positions Bronk as a poet of the sublime and a follower of Wallace Stevens. Based initially on distinct differences in the ideas expressed by Bronk and Stevens, it progresses to demonstrate that Bronk should be understood in a context of postmodernity, and reveals key parallels and similarities between his work and that of notable post-structuralist theorists. It offers the first sustained and detailed overview of the unique place that sleep and dreaming hold in his poetry. These aspects of the discussion variously contribute to a fuller understanding of Bronk as a religious poet. The later chapters of the thesis offer an important overview of the development of his religious outlook, from his first published work in the 1950s to his death in 1999. This is vital to understanding the poetry because previous published criticism has invariably presented a single religious or atheistic stance and overlooked the often contradictory theological dialogue sustained across his poetry. The thesis therefore provides a critical overview of his changing ideas of God, and their interaction with concepts of life and the self, identifying key moments in their development. Beyond original contribution to the existing knowledge and critical understanding of Bronk’s work through original close readings of many poems from across his career, and the hitherto unremarked explorations of its post-structuralist character, the general argument of this thesis – that Bronk is a religious poet of positive agnosticism – will aid all serious readers of his poetry.

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Szymanek, Larissa. "Oculomotor behaviour in healthy subjects, stroke patients and a case of visual form agnosia." Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3444/.

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In my thesis I mainly focus on Milner and Goodale’s model (1995, 2006, 2008) of two visual pathways. While the dorsal stream is supposed to be involved in on-line action, i.e. to deal with the immediate and accurate response to a present target, they state that the ventral stream comes to action when previously perceived and memorised visual target characteristics are required for memory-guided action (off-line action). A lot of evidence for the existence of these separate pathways has come from visual form agnosia patient DF who has repeatedly shown an impaired performance for off-line tasks while she has repeatedly shown an almost flawless performance on on-line tasks (e.g. Goodale et al., 1994a). In DF, this functional dissociation is supposed to be corroborated by her relatively spared dorsal and impaired ventral streams respectively (James et al., 2003). Likewise patients with hemispatial neglect show a pattern similar to patient DF with off-line reaching impairments such as deficits in anti-pointing and delay tasks and relatively spared on-line actions (Rossit et al., 2009b, 2011). Indeed, hemispatial neglect occurs frequently after lesions to the right inferior parietal lobe (e.g. Mort et al., 2003) and Milner and Goodale (1995) speculate that the IPL gets input from ventral stream regions, which would explain the observed deficits in off-line actions. However, due to the heterogeneity of the lesions in patients with hemispatial neglect, an anatomical argument is much more difficult to make. In this thesis I firstly aimed to examine the oculomotor behaviour of neglect patients and secondly of visual form agnosia patient DF in a series of experiments that tap into either on-line or off-line eye-movement tasks to establish whether Milner and colleagues’ (Milner & Harvey, 2006) action dichotomy can be upheld for the oculomotor domain. In the first experiment I aimed to find an answer to the question of whether the bilateral anti-saccade impairment (Butler et al., 2009) is the result of a vector inversion deficit (inability to perform off-line actions) or an inhibition problem. To do that I expanded Butler et al.’s study (2009) on pro- and anti-saccade tasks by testing the patients’ ability to inhibit saccades in an additional fixation condition. In line with Butler et al.’s (2009) study my neglect patients executed many erroneous pro-saccades in the anti-saccade condition and they also showed neglect typical leftward biases in the pro-saccade condition. Furthermore, the results showed that most of the neglect patients were able to withhold eye movements towards targets. As they did not show a general severe inhibition problem it is very likely that the erroneous pro-saccades in the anti-saccade task were caused by a deficit to perform off-line actions rather than by an inhibition problem. These findings were further corroborated in experiment 2 in which neglect patients were asked to perform a more complex fixation task with interleaved fixation and pro-saccade trials. Although the patients performed worse than the controls, they were able to withhold most eye-movements during the fixation trials. Thus the occasionally executed erroneous pro-saccades in fixation trials might reflect the greater demands of the complex fixation task rather than a general inhibition problem. The third experiment examined immediate, stimulus-driven (on-line) and delayed, memory-guided (off-line) saccades. The results showed that all patients were more impaired for the off-line saccades than for on-line action. However this impairment might not be neglect specific as no difference was found between stroke patients with and without neglect. The fourth experiment focused on the ability to perform oculomotor on-line corrections towards perturbed targets that could suddenly and unpredictably change in location. This task required the on-line adjustment of eye-movements to follow the target. Most of the neglect patients were able to correct their saccades in these perturbed trials and general impairments were often connected to parietal lobe lesions, which might involve the visual dorsal stream. Experiment 1, 3 and 4 were also carried out on patient DF. She showed no general problems in performance in the pro-saccade (on-line) and fixation condition in experiment 1, yet she was impaired on anti-saccades (off-line). In experiment 3 she was able to execute saccades towards presented lines but was again impaired in the off-line condition (delayed lines). In experiment 4 she showed no problems to perform on-line corrections towards perturbed stimuli. In summary, on a functional level my results support the distinction between on- and off-line tasks that has been established through the use of pointing and grasping tasks, which I have now extended to the oculomotor domain. The neglect patients, as well as patient DF, were impaired for the tested off-line actions while they showed no general deficits for on-line actions.

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Wisnowski, Jessica Lee. "The specificity of visual recognition impairments following focal brain damage." Diss., University of Iowa, 2007. http://ir.uiowa.edu/etd/136.

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Dennis, Jacob Henry. "On Quaternions and Activity Classification Across Sensor Domains." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/51196.

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Activity classification based on sensor data is a challenging task. Many studies have focused on two main methods to enable activity classification; namely sensor level classification and body-model level classification. This study aims to enable activity classification across sensor domains by considering an e-textile garment and provide the groundwork for transferring the e-textile garment to a vision-based classifier. The framework is comprised of three main components that enable the successful transfer of the body-worn system to the vision-based classifier. The inter-class confusion of the activity space is quantified to allow an ideal prediction of known class accuracy for varying levels of error within the system. Methods for quantifying sensor and garment level error are undertaken to identify challenges specific to a body-worn system. These methods are then used to inform decisions related to the classification accuracy and threshold of the classifier. Using activities from a vision-based system known to the classifier, a user study was conducted to generate an observed set of activities from the body-worn system. The results indicate that the vision-based classifier used is user-independent and can successfully handle classification across sensor domains.
Master of Science

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Silverman, Marjorie L. "A critical examination of the agnostic Buddhism of Stephen Batchelor /." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33926.

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The current study examines the agnostic Buddhism of contemporary scholar and practitioner Stephen Batchelor. The main question under examination is whether the essence of Buddhism is undermined when interpreted through Batchelor's agnostic and "belief-free" lens. In an attempt to answer this question, Batchelor's main philosophical texts---Alone With Others, The Faith to Doubt, and Buddhism Without Beliefs---are analysed, as are three critiques of his work written by Bhikkhu Punnadhammo, Bhikkhu Bodhi, and Sangharakshita. It is concluded that while Batchelor is discarding many of the conventional trappings of Buddhism, he is not placing its integrity at risk.

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Desai, Kalpit V. Bishop Gary. "Agnostic tracking nanoscale, high bandwidth, 3D particle tracking for biology /." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1883.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2007.
Title from electronic title page (viewed Dec. 11, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the joint Department of Biomedical Engineering." Discipline: Biomedical Engineering; Department/School: Medicine.

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Saitas-Zarkias, Konstantinos. "Insights into Model-Agnostic Meta-Learning on Reinforcement Learning Tasks." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290903.

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Meta-learning has been gaining traction in the Deep Learning field as an approach to build models that are able to efficiently adapt to new tasks after deployment. Contrary to conventional Machine Learning approaches, which are trained on a specific task (e.g image classification on a set of labels), meta-learning methods are meta-trained across multiple tasks (e.g image classification across multiple sets of labels). Their end objective is to learn how to solve unseen tasks with just a few samples. One of the most renowned methods of the field is Model-Agnostic Meta-Learning (MAML). The objective of this thesis is to supplement the latest relevant research with novel observations regarding the capabilities, limitations and network dynamics of MAML. For this end, experiments were performed on the meta-reinforcement learning benchmark Meta-World. Additionally, a comparison with a recent variation of MAML, called Almost No Inner Loop (ANIL) was conducted, providing insights on the changes of the network’s representation during adaptation (meta-testing). The results of this study indicate that MAML is able to outperform the baselines on the challenging Meta-World benchmark but shows little signs actual ”rapid learning” during meta-testing thus supporting the hypothesis that it reuses features learnt during meta-training.
Meta-Learning har fått dragkraft inom Deep Learning fältet som ett tillvägagångssätt för att bygga modeller som effektivt kan anpassa sig till nya uppgifter efter distribution. I motsats till konventionella maskininlärnings metoder som är tränade för en specifik uppgift (t.ex. bild klassificering på en uppsättning klasser), så metatränas meta-learning metoder över flera uppgifter (t.ex. bild klassificering över flera uppsättningar av klasser). Deras slutmål är att lära sig att lösa osedda uppgifter med bara några få prover. En av de mest kända metoderna inom området är Model-Agnostic Meta-Learning (MAML). Syftet med denna avhandling är att komplettera den senaste relevanta forskningen med nya observationer avseende MAML: s kapacitet, begränsningar och nätverksdynamik. För detta ändamål utfördes experiment på metaförstärkningslärande riktmärke Meta-World. Dessutom gjordes en jämförelse med en ny variant av MAML, kallad Almost No Inner Loop (ANIL), som gav insikter om förändringarna i nätverkets representation under anpassning (metatestning). Resultaten av denna studie indikerar att MAML kan överträffa baslinjerna för det utmanande Meta-Worldriktmärket men visar små tecken på faktisk ”snabb inlärning” under metatestning, vilket stödjer hypotesen att den återanvänder funktioner som den lärt sig under metaträning.

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Amundberg, Joel, and Martin Moberg. "System Agnostic GUI Testing : Analysis of Augmented Image Recognition Testing." Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-21441.

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Makris, Athanasios, and Andreas Strikos. "Daedalus: A media agnostic peer-to-peer architecture for IPTV distribution." Thesis, KTH, Kommunikationssystem, CoS, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91855.

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IPTV is gaining increasing attention. It is an expanding field where a lot of people are working hard to solve the problems that delay its wide-spread use. One major problem is that the existing IPTV distribution mechanisms do not seem to work well when applied on a large scale. Especially, IP multicast does not seem to meet the requirements of highly demanding IPTV services. In contrast, peer-to-peer architectures for distributing content have been available for a number of years (since the late 1990’s), and their success suggests that this is a promising alternative means of distributing content. Although peer-to-peer architectures are well known for file transfer, this kind of architecture has been used in this thesis for distributing streaming video flows. We combine results from two different approaches - IPTV and peer-to-peer systems - as part of our design and implementation of a new solution for distributing IPTV. Our proposal aims to avoid any weaknesses that the existing solutions have, whilst offering a viable solution for distributing live content.
Intresset kring IPTV ökar hela tiden, och många människor arbetar på att lösa de problem som hindrar området från att växa snabbt. Ett av huvudproblemen är att den existerande IPTV-distributionstekniken inte fungerar bra då den appliceras på stora lösningar. Bland de största problemen är att IP-Multicast inte möter de krav som marknaden ställer på global distribution av material. I motsats till detta har peer-to-peer teknik, som funnits sedan 90-talet, visat sin styrka för fil distribution på en mycket global skala på existerande infrastruktur. I denna uppstats kombinerar vi dessa två områden för att utröna vilka möjligheterna som finns för att optimera kostnaden för distrubition av live-tv samtidigt som vi försöker att undvika de svagheter som normalt associeras med de olika arkitekturerna. Vårt mål är att utnyttja de bästa egenskaperna från de olika teknikerna för att skapa en livsduglig och långsiktig lösning för TV-distribution.

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Richardson, Darren Paul. "The domain agnostic generation of natural language explanations from provenance graphs." Thesis, University of Southampton, 2018. https://eprints.soton.ac.uk/423465/.

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In a data-driven world, being able to record from where data was derived, and by whom is key. The way to represent this information, provenance, on the Web has been standardised by the World Wide Web Consortium as PROV. Furthermore, once provenance has been recorded, it is often necessary to be able to present it back to users. In the state-of-the-art, the interfaces to such provenance tend to be diagrammatic, or rely on very application-specific template-based natural language generation. Both of these approaches have their drawbacks, motivating the search for techniques for generating natural language explanations from domain-generic provenance graphs. This work presents several contributions to the state-of-the-art in this regard. Firstly it presents a novel template-based architecture for natural language generation. This is followed by the novel application of set-cover optimisation techniques to the challenge of sentence selection. Thirdly, this work extends previous research into the role of URIs for lexicalising Linked Data resources, making use of the specific nature of PROV instance data to inform the heuristics used. Fourthly, these techniques are then evaluated in a user study demonstrating that they improve upon the state-of-the-art across the three dimensions of grammatical correctness, fluency, and comprehensibility. This evaluation also showed that the participants preferred the sentences generated using these techniques 56.4% of the time. Following on from these advances, an investigation is conducted into how to structure larger natural language explanations of provenance graphs. This is done by inviting a number of provenance experts to describe a sequence of provenance graphs presented diagrammatically, and analysing the way they approach this task. This reveals that the responses of the experts correlated strongly with the visual layout of the diagrams, and also that the experts were split as to whether to structure those explanations in a chronological or anti-chronological order. Finally, a further study was conducted to investigate how chronology affects the perceived quality of the generated natural language explanations, revealing that in aggregate the participants considered the chronological ordering to be more logical. This dissertation concludes with a summary of the contributions made to the state-of-the-art, as well as by proposing a number of possible areas for future research.

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Gaugaz, Julien [Verfasser]. "Schema-agnostic entity retrieval in highly heterogeneous semi-structured environments / Julien Gaugaz." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2015. http://d-nb.info/1077019424/34.

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Pozzoli, Susanna. "Domain Expertise–Agnostic Feature Selection for the Analysis of Breast Cancer Data." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254661.

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At present, high-dimensional data sets are becoming more and more frequent. The problem of feature selection has already become widespread, owing to the curse of dimensionality. Unfortunately, feature selection is largely based on ground truth and domain expertise. It is possible that ground truth and/or domain expertise will be unavailable, therefore there is a growing need for unsupervised feature selection in multiple fields, such as marketing and proteomics.Now, unlike in past time, it is possible for biologists to measure the amount of protein in a cancer cell. No wonder the data is high-dimensional, the human body is composed of thousands and thousands of proteins. Intuitively, only a handful of proteins cause the onset of the disease. It might be desirable to cluster the cancer sufferers, but at the same time we want to find the proteins that produce good partitions.We hereby propose a methodology designed to find the features able to maximize the clustering performance. After we divided the proteins into different groups, we clustered the patients. Next, we evaluated the clustering performance. We developed a couple of pipelines. Whilst the first focuses its attention on the data provided by the laboratory, the second takes advantage both of the external data on protein complexes and of the internal data. We set the threshold of clustering performance thanks to the biologists at Karolinska Institutet who contributed to the project.In the thesis we show how to make a good selection of features without domain expertise in case of breast cancer data. This experiment illustrates how we can reach a clustering performance up to eight times better than the baseline with the aid of feature selection.
Högdimensionella dataseter blir allt vanligare. Problemet med funktionsval har redan blivit utbrett på grund av dimensionalitetens förbannelse. Dessvärre är funktionsvalet i stor utsträckning baserat på grundläggande sanning och domänkunskap. Det är möjligt att grundläggande sanning och/eller domänkunskap kommer att vara otillgänglig, därför finns det ett växande behov av icke-övervakat funktionsval i flera områden, såsom marknadsföring och proteomics.I nuläge, till skillnad från tidigare, är det möjligt för biologer att mäta mängden protein i en cancercell. Inte undra på att data är högdimensionella, människokroppen består av tusentals och tusentals proteiner. Intuitivt orsakar bara en handfull proteiner sjukdomsuppkomsten. Det kan vara önskvärt att klustrera cancerlidarna, men samtidigt vill vi hitta proteiner som producerar goda partitioner.Vi föreslår härmed en metod som är utformad för att hitta funktioner som kan maximera klustringsprestandan. Efter att vi delat proteinerna i olika grupper klustrade vi patienterna. Därefter utvärderade vi klustringsprestandan. Vi utvecklade ett par pipelines. Medan den första fokuserar på de data som laboratoriet tillhandahåller, utnyttjar den andra både extern data på proteinkomplex och intern data. Vi ställde gränsen för klusterprestationen tack vare biologerna vid Karolinska Institutet som bidragit till projektet.I avhandlingen visar vi hur man gör ett bra utbud av funktioner utan domänkompetens vid bröstcancerdata. Detta experiment illustrerar hur vi kan nå en klusterprestation upp till åtta gånger bättre än baslinjen med hjälp av funktionsval.

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Reinholdsen, Fredrik. "A Blind Constellation Agnostic VAE Channel Equalizer and Non Data-Assisted Synchronization." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-86062.

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High performance and high bandwidth wireless digital communication underlies much of modern society. Due to its high value to society, new and improved digital communication technologies, allowing even higher speeds, better coverage, and lower latency are constantly being developed. The field of Machine Learning has exploded in recent years, showing incredible promise and performance at many tasks in a wide variety of fields. Channel Equalization and synchronization are critical parts of any wireless communication system, to ensure coherence between the transmitter and receiver, and to compensate for the often severe channel conditions. This study mainly explores the use of a Variational Autoencoder (VAE) architecture, presented in a previous study, for blind channel equalization without access to pilot symbols or ground-truth data. This thesis also presents a new, non data-assisted method of carrier frequency synchronization based around the k-means clustering algorithm. The main addition of this thesis however is a constellation agnostic implementation of the reference VAE architecture, for equalization of all rectangular QAM constellations. The approach significantly outperforms the traditional blind adaptive Constant Modulus algorithm (CMA) on all tested constellations and signal to noise ratios (SNRs), nearly equaling the performance of a non-blind Least Mean Squares (LMS) based Decision Feedback Equalizer (DFE).

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Smith, Wendy. "A study of the relationship between reversals and several factors in the grade 2 learner." Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-10142009-174408/.

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Makitla, Mokone Ishmael. "A conceptual model of an access-technology-agnostic delivery mechanism for ICT4D services." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1019756.

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Information and Communication Technology for Development (ICT4D) is an emerging research area that is concerned with the beneficial applications of Information and Communications Technology (ICT) to achieve developmental goals. ICT4D is thus concerned with designing and developing innovative technologies for resource-constrained environments for applications in key areas of social development such as health, agriculture and education. The ICT4D initiatives, therefore, are driving three main tasks, namely developing the required infrastructure (connectivity, electricity and computing devices) sustainably, building the required ICT human capacity, and providing access to digital content and services. Each of these three main thrusts necessitates innovation. This study addresses the evident lack of delivery mechanisms to facilitate access to digital content and services to end-users through the technologies that these end-users already possess. This lack of innovative delivery mechanisms is both an impediment to achieving equitable access to digital content and service and an opportunity to innovate. Therefore, drawing from the theoretical background of ICT4D, this study develops a set of technical and socio-technical requirements that the missing delivery mechanisms should satisfy. The study also explores the Service Delivery Platform (SDP) concept as a technically viable basis for the required delivery mechanisms. The study then develops a conceptual model of an Access-Technology-Agnostic Delivery Mechanism as a possible delivery mechanism that facilitates equitable access to digital content and services within an ICT4D context. The relevance of the conceptual model is established and, through a prototype implementation, the technical feasibility and utility of the conceptual model is demonstrated. The conceptual model is demonstrated through a proof of concept implementation using standards-based open source technologies. The proof of concept clearly demonstrates that the access-technology-agnostic delivery of digital content and services is achievable, thus making the same service accessible through different access technologies. In developing the Access-Technology-Agnostic Delivery Mechanism, this study contributes through innovation to providing access to digital content and services in an access-technology-agnostic manner.

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Thomas, R. M. "The anatomical and functional correlates of category-specificity." Thesis, Aston University, 2004. http://publications.aston.ac.uk/12262/.

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The dramatic effects of brain damage can provide some of the most interesting insights into the nature of normal cognitive performance. In recent years a number of neuropsychological studies have reported a particular form of cognitive impairment where patients have problems recognising objects from one category but remain able to recognise those from others. The most frequent ‘category-specific’ pattern is an impairment identifying living things, compared to nonliving things. The reverse pattern of dissociation, i.e., an impairment recognising and naming nonliving things relative to living things, has been reported albeit much less frequently. The objective of the work carried out in this thesis was to investigate the organising principles and anatomical correlates of stored knowledge for categories of living and nonliving things. Three complementary cognitive neuropsychological research techniques were employed to assess how, and where, this knowledge is represented in the brain: (i) studies of normal (neurologically intact) subjects, (ii) case-studies of neurologically impaired patients with selective deficits in object recognition, and (iii) studies of the anatomical correlates of stored knowledge for living and nonliving things on the brain using magnetoencephalography (MEG). The main empirical findings showed that semantic knowledge about living and nonliving things is principally encoded in terms of sensory and functional features, respectively. In two case-study chapters evidence was found supporting the view that category-specific impairments can arise from damage to a pre-semantic system, rather than the assumption often made that the system involved must be semantic. In the MEG study, rather than finding evidence for the involvement of specific brain areas for different object categories, it appeared that, when subjects named and categorised living and nonliving things, a non-differentiated neural system was involved.

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Dzhartova, Viliana, Hrishabh Sandilya, Sierra Flanigan, and Alena Iuzefovich. "Integrating Sustainability into Sector Agnostic Innovation Hubs: The Case of Venture Café Global Network." Thesis, Blekinge Tekniska Högskola, Institutionen för strategisk hållbar utveckling, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-18333.

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Given the increasing complexity of global ecological and social problems, innovation plays a key role in solutions for sustainable development. Within innovation ecosystems, intermediaries such as innovation hubs play an important part in influencing other actors like startups, investors and policymakers to create solutions for change. Therefore, it is essential that innovation hubs incorporate sustainability into their practices, if they are to contribute to addressing the Global Sustainability Challenge (GSC). To see how this could be done, this study examines the case of the Venture Café Global Network (VCGN) a type of sector agnostic innovation hub. The study used a multi-method qualitative approach. Data was gathered through semi-structured interviews with different players in the innovation ecosystem, as well as with actors from within VCGN, and through a documentary analysis. The results and discussion are presented according to certain overarching themes that emerged from the interviews and answer the research questions. Along with a longer list of recommendations, this study concludes that the adoption of a shared organisational definition of sustainability is the bedrock for any sustainability integration and vital for innovation hubs to impact other actors in their innovation ecosystems, to address the GSC.

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Boyd, William Robert Dawson III. "Reactor agnostic multi-group cross section generation for fine-mesh deterministic neutron transport simulations." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/112525.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 487-495).
A key challenge for full-core transport methods is reactor agnostic multi-group cross section (MGXS) generation. Monte Carlo (MC) presents the most accurate method for MGXS generation since it does not require any approximations to the neutron flux. This thesis develops novel methods that use MC to generate the fine-spatial mesh MGXS that are needed by high-fidelity transport codes. These methods employ either engineering-based or statistical clustering algorithms to accelerate the convergence of MGXS tallied on fine, heterogeneous spatial meshes by Monte Carlo. The traditional multi-level approach to MGXS generation is replaced by full-core MC calculations that generate MGXS for multi-group deterministic transport codes. Two pinwise spatial homogenization schemes are introduced to model the clustering of pin-wise MGXS due to spatial self-shielding spectral effects. The Local Neighbor Symmetry (LNS) scheme uses a nearest neighbor-like analysis of a reactor geometry to determine which fuel pins should be assigned the same MGXS. The inferential MGXS (iMGXS) scheme applies unsupervised machine learning algorithms to "noisy" MC tally data to identify clustering of pin-wise MGXS without any knowledge of the reactor geometry. Both schemes simultaneously account for spatial self-shielding effects while also accelerating the convergence of the MC tallies used to generate MGXS. The LNS and iMGXS schemes were used to model MGXS clustering from radial geometric heterogeneities in a suite of 2D PWR benchmarks. Both schemes reduced U-238 capture rate errors by up to a factor of four with respect to schemes which neglect to model MGXS clustering. In addition, the schemes required an order of magnitude fewer MC particle histories to converge MGXS for multi-group deterministic calculations than a reference MC calculation. These results demonstrate the potential for single-step MC simulations of the complete heterogeneous geometry as a means to generate reactor agnostic MGXS for deterministic transport codes. The LNS and iMGXS schemes may be valuable for reactor physics analyses of advanced LWR core designs and next generation reactors with spatial heterogeneities that are poorly modeled by the engineering approximations in today's methods for MGXS generation.
by William Robert Dawson Boyd, III.
Ph. D.

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