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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Modellierung von On-Chip-Trace-Architekturen für eingebettete Systeme

Irrgang, Kai-Uwe 13 July 2015 (has links) (PDF)
Das als Trace bezeichnete nicht-invasive Aufzeichnen von Systemzuständen, während ein eingebettetes System unter realen Einsatzbedingungen in Echtzeit läuft und mit der Systemumgebung interagiert, ist ein wichtiger Teil von Softwaretests. Die Notwendigkeit für den On-Chip-Trace resultiert aus der rückläufigen Einsetzbarkeit etablierter Werkzeuge für den Off-Chip-Trace. Ein wesentlicher Bestandteil von On-Chip-Trace-Architekturen ist die Volumenreduktion der Tracedaten in deren Entstehungsgeschwindigkeit direkt auf dem Chip. Der Schwerpunkt liegt auf dem Trace des Instruktionsflusses von Prozessoren. Der aktuelle Stand der Forschung zeigt zwei Ausprägungen. Bei einfachen Lösungen ist der Kompressionsfaktor zu klein. Aufwendigere Lösungen liefern einen unvollständigen Instruktionstrace, wenn auch sequentielle Befehle bedingt ausgeführt werden. Bisher existieren keine Lösungen, die einen vollständigen Instruktionstrace mit hoher Kompression realisieren. Diese Lücke wird in der vorliegenden Arbeit geschlossen. Der systematische Entwurf der neuen On-Chip-Trace-Architektur beginnt mit der umfassenden Analyse typischer Benchmarkprogramme. Aus den Ergebnissen werden grundlegende Entwurfsentscheidungen abgeleitet. Diese Bitsequenzen von Ausführungsbits, die bei der bedingten Befehlsausführung entstehen, und die Zieladressen ausgeführter indirekter Sprünge werden in unabhängigen Kompressoren verarbeitet. Ein nachgeschalteter Kompressor für die Messages der anderen beiden Kompressoren ist optional und kann die Kompression weiter steigern. Diese Aufteilung stellt ein architektonisches Novum dar. Die Kompression von Bitsequenzen ist bisher ein weitestgehend unbehandeltes Feld. Implementiert worden ist hierfür ein gleitendes Wörterbuch mit der Granularität von Einzelbits. Die Vergleiche mit den untersuchten existierenden Architekturen zeigen die Überlegenheit der neuen Architektur bei der Kompression. Ein vollständiger Instruktionstrace ist für Prozessoren mit und ohne bedingt ausführbaren sequentiellen Befehlen realisiert worden.
222

Increasing the Performance and Predictability of the Code Execution on an Embedded Java Platform / Ansätze zur Steigerung der Leistungsfähigkeit und Vorhersagbarkeit der Codeausführung auf einer eingebetteten Java-Plattform

Preußer, Thomas 21 October 2011 (has links) (PDF)
This thesis explores the execution of object-oriented code on an embedded Java platform. It presents established and derives new approaches for the implementation of high-level object-oriented functionality and commonly expected system services. The goal of the developed techniques is the provision of the architectural base for an efficient and predictable code execution. The research vehicle of this thesis is the Java-programmed SHAP platform. It consists of its platform tool chain and the highly-customizable SHAP bytecode processor. SHAP offers a fully operational embedded CLDC environment, in which the proposed techniques have been implemented, verified, and evaluated. Two strands are followed to achieve the goal of this thesis. First of all, the sequential execution of bytecode is optimized through a joint effort of an optimizing offline linker and an on-chip application loader. Additionally, SHAP pioneers a reference coloring mechanism, which enables a constant-time interface method dispatch that need not be backed a large sparse dispatch table. Secondly, this thesis explores the implementation of essential system services within designated concurrent hardware modules. This effort is necessary to decouple the computational progress of the user application from the interference induced by time-sharing software implementations of these services. The concrete contributions comprise a spill-free, on-chip stack; a predictable method cache; and a concurrent garbage collection. Each approached means is described and evaluated after the relevant state of the art has been reviewed. This review is not limited to preceding small embedded approaches but also includes techniques that have proven successful on larger-scale platforms. The other way around, the chances that these platforms may benefit from the techniques developed for SHAP are discussed.
223

The cognitive basis of goal-directed behaviour

Carroll, Ellen Laura January 2014 (has links)
An unresolved issue exists in the study of mental ability: which aspect of cognition is responsible for the emergence of psychometric “g” (Spearman, 1904, 1927), a general factor that predicts performance in all kinds of cognitive tasks and many important life outcomes? On the basis of themes present in the literature on fluid intelligence (Chapter 1), this thesis explores the relative contributions of processing, storage, and task modelling demands to the recruitment of g in task performance. Six experiments are presented which employed two computer-based tasks. The tasks were designed such that the level of demand for processing and storage was separated and manipulated in order to establish their relationship to scores on a standard test of g. Task manipulations were implemented in the context of varying the number of distinct verbal chunks in which task instructions were presented, whilst controlling for the presented amount of operative task-relevant information. The findings showed that the recruitment of g in task performance was strengthened by the presence (versus the absence) of a requirement to inhibit a prepotent response tendency (Experiments 1, 2, and 3), and by the presence of requirements to inhibit a prepared response and to maintain and update information in working memory (Experiments 4 and 5). However, these effects were observed only when task instructions were presented as four (and not as two) distinct rules. Additional findings showed that reconceptualisation of task requirements—that is, flexibly imposing order on a complex set of instructions thus reducing the number of distinct verbal chunks—was dependent on performance on the test of Spearman’s g (Experiments 3 through 6). These findings are deemed consistent with a task conceptualisation theory of g, with real-time execution demand, particularly inhibition, posing as a risk factor for the recruitment of g only when task requirements are maintained in mind as a relatively large number of chunks or rules.
224

Slurs in speech and thought / Les péjoratifs dans le langage et la pensée

Thommen, Tristan 19 June 2018 (has links)
Cette thèse s'intéresse à la structure, aux fonctions, et aux bases cognitives des termes d'offense (tels que le terme "boche"). Les termes d'offense, ainsi que leurs équivalents psychologiques, posent des problèmes intéressants et possiblement fondationnels à propos de la nature de la signification, de l'expressivité dans les langues naturelles, du rôle des émotions dans la catégorisation. Ce travail discute de ces questions - ainsi que de nombreuses autres - en s'intéressant à différentes théories existantes ou originalesdu phénomène. De nouvelles données linguistiques sont mises en avant qui remettent en cause des théories linguistiques telles que les visions vériconditionnelles ou présuppositionnelles du phénomène, et de nouvelles théories non-linguistiques du phénomène sont développées, invoquant les concepts de qualité seconde ou la notion d'essence. Les propriétés linguistiques particulières des termes d'offense, telles que la projection ou l'expressivité, apparaissent dans ce travail être des conséquences linguistiques d'un phénomène essentiellement psychologique : la possibilité d'une composante émotionnelle ou évaluative dans la structure même des concepts. / The present work investigates the structure, function and cognitive underpinnings of slurring terms (such as "boche"). Slurring terms, and the mental correlates that I posit they have, raise interesting and possibly foundational issues about the nature of meaning, about expressivity in natural language, about the role of emotions in categorization. I discuss these questions - among many others - by studying different existing or original accounts of the phenomenon. I present novel linguistic evidence against linguistic views such as truth-conditional or presuppositional accounts, and develop new psychological (i.e. non-linguistic) theories of the phenomenon based on a connection with responsedependent concepts, or with essentialist concepts. The interesting linguistic properties of slurs, such as projection and expressivity, appear to be the linguistic consequences of the essentially mental fact that concepts may be loaded with emotional or evaluative content.
225

Modélisation bayésienne du développement conjoint de la perception, l'action et la phonologie / Bayesian modeling of the joint development of perception, action and phonology

Barnaud, Marie-Lou 19 January 2018 (has links)
A travers les tâches de perception et de production, les humains peuvent manipuler non seulement des mots et des phrases mais également des unités de plus bas niveau tels des syllabes et des phonèmes. Les études en phonétique sont principalement focalisées sur ces seconds types d'unitées. Un des objectif majeur dans ce domaine et de comprendre comment les humains acquiert et manipulent ces unités.Dans cette thèse, nous nous intéressons à cette question à travers l'utilisation de la modélisation computationnelle en réalisant des simulation informatiques à l'aide d'un modèle bayésien de la communication nommé COSMO (“Communicating Objects using Sensory-Motor Operations”). Nos études s'étendres à trois aspects.Dans une première partie, nous étudions les représentations cognitives des unités phonétiques. Il est maintenant bien établie que les unités sont caractérisées par des représentations auditives et motrices. En examinant leur rôle respectifs durant le développement, nous établissons leur complémentarité à travers ce que nous nommons la propriété <<bande étroite/bande large>>.Dans une seconde partie, nous nous intéressons à la variabilité des unités phonétiques, notamment à travers l'étude de la corrélation des idiosyncrasies en perception et en production. En comparant plusieurs conditions de développement, nous établissons qu'elles s'acquiert à travers un processus de reproduction des catégories plutôt qu'à une répétition des sons.Dans une troisième partie, nous analysons la nature des catégories phonétiques. En phonétique, il y a un débat autour du statut des syllabes vs. des phonèmes dans la communication de la parole. Dans nos simulations, nous examinons leurs acquisitions respectives à travers un apprentissage non supervisée et montrons les particularités nécessaires à la communication. / Through perception and production tasks, humans are able to manipulate not only high-level units like words or sentences but also low-level units like syllables and phonemes. Studies in phonetics mainly focus on the second type of units. One of the main goal in this field is to understand how humans acquire and manipulate these units and how they are stored in the brain. In this PhD thesis, we address this set of issues by using computer modeling, performing computer simulations with a Bayesian model of communication, named COSMO (“Communicating Objects using Sensory-Motor Operations”). Our studies extend in three ways.In a first part, we investigate the cognitive content of phonetic units. It is well established that phonetic units are characterized by both auditory and motor representations. It also seems that these representations are both used during speech processing. We question the functional role of a double representation of phonetic units in the human brain, specifically in a perception task. By examining their respective development, we show that these two representations have a complementary role during perception: the auditory representation is tuned to recognize nominal stimuli whereas the motor representation has generalization properties and can deal with stimuli typical of adverse conditions. We call this the “auditory-narrow/motor-wide” property.In a second part, we investigate the variability of phonetic units. Despite the universality of phonetic units, their characterization varies from one person to another, both in their articulatory/motor and acoustic content. This is called idiosyncrasies. In our study, we aim at understanding how they appear during speech development. We specifically compare two learning algorithms, both based on an imitation process. The first version consists in sound imitation while the second version exploits phoneme imitation. We show that idiosyncrasies appear only in the course of a phoneme imitation process. We conclude that motor learning seems rather driven by a linguistic/communication goal than motivated by the reproduction of the stimulus acoustic properties.In a third part, we investigate the nature of phonetic units. In phonetics, there is a debate about the specific status of the syllable vs phoneme in speech communication. In adult studies, a consensus is now found: both units would be stored in the brain. But, in infant studies, syllabic units seem to be primary. In our simulation study, we investigate the acquisition of both units and try to understand how our model could “discover” phonemes starting from purely syllabic representations. We show that contrary to syllables and vowels, consonants are poorly characterized in the auditory representation, because the categories overlap. This is due to the influence of one phoneme on its neighbors, the well-known “coarticulation”. However, we also show that the representation of consonants in the motor space is much more efficient, with a very low level of overlap between categories. This is in line with classical theories about motor/articulatory invariance for plosives. In consequence, phonemes, i.e. vowels and consonants, seem well displayed and likely to clearly emerge in a sensory-motor developmental approach such as ours.Through these three axes, we implemented different versions of our model. Based on data from the literature, we specifically cared about the cognitive viability of its variables and distributions and of its learning phases. In this work, modeling computation has been used in two kinds of studies: comparative and explanatory studies. In the first ones, we compared results of two models differing by one aspect and we selected the one in accordance with experimental results. In the second ones, we interpreted a phenomenon observed in literature with our model. In both cases, our simulations aim at better understanding data from the literature and provide new predictions for future studies.
226

Développement du raisonnement analogique : rôle de la composante éxécutive d'inhibition / The development of analogical reasoning : role of the executive component of inhibition

Vezneva, Milena 24 October 2011 (has links)
Nous avons étudié le développement du raisonnement par analogie. La conception traditionnelle de ce développement est qu’il dépend de l’accroissement des connaissances des enfants (Gentner, 1983, 1988 ; Goswami & Brown, 1989, 1990). Nous l’avons abordé sous l’angle du développement des fonctions exécutives, en particulier - de la composante d’inhibition. La capacité d’inhibition permet la suppression des informations saillantes mais non pertinentes pour faire l’analogie. Elle est requise lors de la recherche de la solution analogique. Neuf études ont été réalisées dans le cadre de cette thèse. Nous avons utilisé une tâche classique d’analogie du type A : B :: C : ?. Le rôle de la capacité d’inhibition a été testé par la présence de distracteurs perceptifs ou sémantiques qui entrent en compétition avec la solution analogique. Ils doivent être inhibés lors de sa recherche. Les résultats montrent que les informations saillantes mais non pertinentes pour trouver la solution analogique interfèrent avec sa découverte ou sa construction. Par conséquent, les performances des enfants à la tâche d’analogie dépendraient du degré de développement de leurs fonctions exécutives. Ces résultats sont compatibles avec les résultats de Richland, Morrison & Holyoak (2006) qui expliquent les performances des enfants à une tâche d’analogie par les limitations dans leur fonctionnement exécutif. / We explored the development of the analogical reasoning. The traditional conception of this development is that it is dependent of knowledge accretion in children (Gentner, 1983, 1988; Goswami & Brown, 1989, 1990). We used a different approach which explains it as dependent of the development of the executive functions, particularly of the component of inhibition. The capacity of inhibition allows the suppression of the salient but irrelevant information for analogy-making in children. It is required while searching for the analogical solution. Nine studies involving a classical analogy-making task A : B :: C : ? were performed in this dissertation. The role of the capacity of inhibition was tested using perceptual or semantic distractors conflicting with the analogical solution. The distractors must be inhibited while searching for the analogical solution. Results show that all salient but irrelevant information for analogy-making interferes with the discovery or the construction of the analogical solution. Therefore, children’s performances of the analogy-making task depend on the degree of development of their executive functions. These results are consistent with the results of Richland, Morrison & Holyoak (2006) explaining children’s performances on an analogy-making task by the limitations of their executive functioning.
227

Comprehension of complex animation : cueing, segmentation and 2D / 3D presentations / Comprehension d'animations complexes : signalisation, segmentation et présentations en 2D et 3D

Putri, Dian Kemala 25 November 2011 (has links)
Pas de résumé en français / The goal of our studies was to test the effect of segmentation, cueing, and 2D/3D presentations to foster complex animation rocessing. The material was an upright mechanical piano system. We used an eye tracking system which provides information about learners’ attention direction during the animation processing. We analyzed the effect of the format presentations and the eye movements during learning. Based on animation and multimedia research background, four experiments were conducted. In the first experiment the effect of the presentation of simplified external representations on learning from complex animation was investigated. Experiment two and three aimed at studying the cognitive processes involved in learning to complex mechanism system with new cueing techniques with spatial-temporal colored tokens. In the fourth experiment, 2D and 3D presentation of the same animated content were compared. Results of these experiments showed that (1) the use of a dual format presentation is better for developing a dynamic mental model from the animation than a single format, (2) the signaling strategies using cued tokens of dual format can guide efficiently learner’s building of mental model and can enhance learner’s comprehension of complex system, (3) a sequential format presentation followed by an animation format presentation helps the learner to understand the key stages of a dynamic process and to create a high quality mental model, (4) 3D animation presentation is better than 2D animation presentation to direct attention on relevant component of the animation. For depth processing, comprehension with 3D animation presentation is better than 2D animation format. Eye tracking measures provided insights into how people understood and learned complex systems. The analysis of eye tracking also contributed to the understanding of the subject’s perceptual processing during learning. Overall, results provide a significant contribution in the field of learning with complex animation. Recommendations in the ergonomics area for the design of animations are proposed.
228

Évolution des liens entre théorie de l'esprit, syntaxe et fonctions exécutives au cours du développement chez les personnes avec ou sans troubles du spectre autistique / Evolution of the links between theory of mind, syntax, and executive functions during development in children and adults with or without autism spectrum disorders

Burnel, Morgane 01 December 2017 (has links)
Le déficit de Théorie de l’Esprit (TE), c'est-à-dire de la capacité à prédire et à interpréter le comportement d’autrui sur la base des états mentaux (e.g., pensées, désirs, croyances) qu’on lui prête, reste un problème cognitif majeur dans les Troubles du Spectre Autistique (TSA). D'après la littérature différentes composantes syntaxiques et exécutives sont susceptibles d’intervenir dans la compréhension des états mentaux. Dans ce travail de thèse nous nous sommes intéressées à l’apport de la syntaxe d’enchâssement (i.e., Phrases Complétives, PC ; Phrases Relatives, PR) ainsi qu’au rôle des Fonctions Exécutives (FE) telles que l’inhibition, la flexibilité et la Mémoire de Travail (MT). Les objectifs principaux de cette thèse étaient : (1) Évaluer le développement de la TE au-delà de l’attribution de Fausses Croyances (FC) et indépendamment du langage chez les enfants avec ou sans TSA, (2) Déterminer quelles composantes syntaxiques et exécutives sont les plus utiles à la TE, (3) Évaluer l’évolution des liens entre syntaxe, Fonctions Exécutives (FE) et TE au cours du développement et (4) Évaluer l’existence de déficits syntaxiques et exécutifs ainsi que la nature des stratégies de compensation de la TE dans les TSA. Sur la base de nos résultats, à plus long terme nous souhaitons développer des protocoles de remédiation de la TE ciblant les fonctions cognitives qui la sous-tendent en fonction de l’âge des individus. Pour cela, nous avons mené plusieurs études comportementales chez des enfants et des adultes avec ou sans TSA en utilisant des tâches de TE à la demande verbale et exécutive réduite. Nos travaux ont mené à la créaction d’un outil permettant d’évaluer ledéveloppement de la TE au-delà des tâches de FC et en minimisant l’impact des variables confondues telles que le langage. Ils ont également permis de mettre en évidence une implication particulière des PC et de la MT pour la TE pendant l’enfance mais pas à l’âge adulte, suggérant que ces composantes cognitives sont utiles au développement de la TE plutôt qu’au raisonnement de TE en tant que tel. Nos résultats n’ont pas toujours permis de mettre en évidence l’existence de déficits syntaxiques ou exécutifs dans les TSA. Ceci suggère que ces déficits ne sont peut-être pas présents chez tous les individus avec TSA et soulèvent également l’importance d’utiliser des tâches écologiques pour évaluer la présence de déficits subtils. Par ailleurs, l’étude de la nature des stratégies de compensation de la TE dans les TSA s’est avérée plus compliquée que prévue. Nous suggérons que cela provient de la difficulté à identifier précisément les individus qui les mettent en oeuvre. / Theory of Mind (ToM), that is to say the ability to predict and interpret others’ behavior based on their mental states (e.g., thoughts, desires, beliefs) is affected in Autism Spectrum Disorders (ASD). According to the literature, several syntactic and executive abilities are likely to be implied in mental state understanding. In this thesis, we were interested in the role of the syntax of embedding (i.e., Complement Sentences, CS; Relative Clause Sentences, RCS) and in the role of Executive Functions (EF) such as inhibition, flexibility and Working Memory (WM). The main goals of this thesis were to (1) Assess ToM development beyond False Belief (FB) attribution and independently from language in children with or without ASD, (2) Determine the syntactic and executive components that are the most useful for ToM, (3) Highlight the evolution of the links between syntax, Executive Functions (EF) and ToM during development (4) Identify the existence of syntactic and executive deficits, as well as the nature of compensation strategies for ToM in ASD. The long term goal was to allow the development of remediation protocols for ToM targeting cognitive abilities which underlie it depending on people’s age. For that purpose, we ran several behavioral studies in children and adults with or without ASD using ToM tasks entailing reduced verbal and executive demands. Our work lead to the creation of a tool enabling the assessment of ToM development beyond FB tasks while minimizing the impact of confounding variables such as language. Our findings highlighted a particular role of CS and WM in ToM during childhood but not during adulthood, suggesting that these cognitive abilities are useful for ToM development rather than ToM reasoning per se. Our results did not always highlight the existence of syntactic and executive deficits in ASD and thus illustrated the marked heterogeneity of these skills in this population but also importance of using ecological tasks to assess subtle deficits. Moreover, the study of the nature of compensation strategies for ToM in ASD turned out to be more challenging than expected and we propose that this may have resulted from the difficulty to precisely identify peoplewho implement them.
229

Estudos sobre a formacao do complexo do sup(153)Sm com EDTMP (acido etilenodiaminotetrametileno-fosfonico) e dos complexos do sup(153)Sm com outros fosfonatos, em temperatura ambiente

GASIGLIA, HAROLDO T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:09Z (GMT). No. of bitstreams: 1 07013.pdf: 6587866 bytes, checksum: e1c1d18518e5c83a812cb4dc4c0cb496 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
230

Desenvolvimento de metodos de medida de atividade de radionuclideos utilizados em medicina nuclear - aplicacao na padronizacao do sup(51) Cr e sup(153) Sm

LAVRAS, WILSON de O. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:39Z (GMT). No. of bitstreams: 1 08346.pdf: 3889708 bytes, checksum: 998810087525503d37c9b42eac89fcec (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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