Fast spreading unknown viruses have caused major damage on computer systems upon their initial release. Current detection methods have lacked capabilities to detect unknown virus quickly enough to avoid mass spreading and damage. This dissertation has presented a behavior based approach to detecting known and unknown viruses based on their attempt to replicate. Replication is the qualifying fundamental characteristic of a virus and is consistently present in all viruses making this approach applicable to viruses belonging to many classes and executing under several conditions. A form of replication called self-reference replication, (SR-replication), has been formalized as one main type of replication which specifically replicates by modifying or creating other files on a system to include the virus itself. This replication type was used to detect viruses attempting replication by referencing themselves which is a necessary step to successfully replicate files. The approach does not require a priori knowledge about known viruses. Detection was accomplished at runtime by monitoring currently executing processes attempting to replicate. Two implementation prototypes of the detection approach called SRRAT were created and tested on the Microsoft Windows operating systems focusing on the tracking of user mode Win32 API system calls and Kernel mode system services. The research results showed SR-replication capable of distinguishing between file infecting viruses and benign processes with little or no false positives and false negatives.

Abstract This thesis aims to analyze metadramatic elements in Shakespearean history plays mainly from the interplay between the actor and the audience. I do not focus on a particular history play but on two characters: Richard III and Prince Hal. Different from most critics of metadrama, I do not search for ruptures in a dramatic text or interpret those ruptures from the deconstructionist¡¦s perspective. Nor do I view metadrama as an established theory when I notice that most critics of metadrama fail to offer a succinct definition to the term. To be specific, metadrama is a kind of dramatic practice on the Renaissance stage. Furthermore, matadrama is constituted of types of metadramatic modes, and during my research, I gradually realize that self-reference is a peculiar phenomenon in history plays. The function of self-reference is to challenge the audience¡¦s fixed perception of things and to reexamine the part of exaggeration and counterfeit in the historical documents. Shakespeare uses self-reference to develop not only the personality of dramatic personae but also his theatrical perspective of historical characters.¡@By analyzing self-reference, I wish to clarify Shakespeare¡¦s attitude toward historical characters. Also, I shall argue that Shakespeare modifies the historical portrayals of Richard III and Prince Hal and authenticates the theatrical perspective of them.

Damage to the brain can affect the core of the individual, i.e. the self. Results from a small number of studies with amnesic individuals indicate that patients' ability to show preserved knowledge of self may vary. The present study explored self-knowledge in patients with memory impairment as a result of confabulation, mild cognitive impairment, Alzheimer's disease and acquired brain damage. We found that different memory disorders differentially affected patients' self-knowledge. At least some patients showed a preserved sense of self, and were able to acquire information about another person that they had met postmorbidly. Frontal function and stability of cognitive impairments over time appear to be two variables important in determining whether patients can have a consistent and updated sense of self. We also explored the extent to which self-referential and other-referential processing might enhance memory in individuals with memory-impairment. The self-reference effect (SRE) and other-reference effect (ORE) have been consistently found in normal adults. Results indicated that patients showed a normal SRE and ORE. The SRE and ORE appeared to be at least partly dependent on degree of knowledge of the person being referenced, and were also related to general memory and frontal function. Only the SRE, however, was also related to patients' ability to improve memory as a result of emotional processing. These findings may have important implications for caregivers and healthcare professionals working with memory-impaired patients, and may pave the way to novel memory rehabilitation methods.

国立情報学研究所で電子化したコンテンツを使用している。

Cette recherche, qui porte sur la référence à soi dans le langage de l’enfant atteint d’autisme, vise deux objectifs. Le premier d’entre eux est de montrer que la référence à soi dépend de la cognition de la personne. Il en ressort que du fait de sa cognition particulière la personne avec autisme use d’un langage différent qualitativement et ce, de manière durable. Le deuxième objectif consiste à intégrer la référence à soi tant dans son usage typique qu’autistique au sein d’une théorie sémantique pragmatique et cognitive. Pour le premier objectif, je me suis appuyée sur l’analyse de trois corpus de langue française : un corpus longitudinal d’un enfant neuro-typique et deux corpus d’enfants atteints d’autisme. L’analyse des corpus a montré que ces trois enfants construisent pareillement la référence à soi à partir de leurs intentions communicatives et de l’input. Pourtant, chez l’enfant atteint d’autisme, le modèle mental de référence à soi est déterminé par des mécanismes cognitifs qui fonctionnent différemment chez lui. Il en découle une expression de référence à soi particulière, qui se caractérise par une priorité donnée à des formes non-standard, qui persistent à travers les âges parallèlement à l’usage standard de la première personne.Pour le second objectif, j’ai confronté deux théories contemporaines liées au concept de référence : la théorie de la référence directe (David Kaplan) et la théorie néo-frégéenne (Gareth Evans), qui sont reconnues comme deux philosophies de la référence (au locuteur). Il en ressort que la position mentaliste d’Evans pourrait mieux rendre compte de ce qui se passe au niveau mental lorsque l’on réfère à soi : c’est sous un mode de présentation épistémique spécifique que l’on réfère en réalité à soi-même, quelle que soit la situation. / This research focuses on self-reference in the speech of autistic children. Throughout this work, two main objectives were developed. The first was to show that self-reference depends on the cognition of the person. Consequently, the autistic person will manifest a different cognition over the long term, expressed qualitatively in terms of speech. The second objective was to integrate self-reference in its typical and autistic use into a semantic, pragmatic and cognitive theory.For the first objective, I based my analysis on three French corpora: a longitudinal corpus of a neurotypical child and two corpora of two children with autism. The analysis of the corpora showed that the three children construct their self-reference similarly, they build on their communicative intentions and the input. However, the two autistic children’s mental model of self-reference is determined by cognitive mechanisms that function differently for them. This results in self-reference expression characterized by the long-term use of non-standard forms, in parallel with the standard first person forms.For the second objective, I compared two contemporary theories of reference: the direct reference theory (David Kaplan) and the neo-Fregean theory (Gareth Evans) which are known as two philosophies of reference (in relation to the speaker). Evans’ mentalist position can make sense of what happens at the mental level when one refers to oneself: in all cases, reference to oneself is actually achieved through a specific and epistemic presentation.

Orientador: Antonio Trajano Menezes Arruda / Banca: Mariana Cláudia Broens / Banca: André Leclerc / Resumo: Este trabalho consiste num esforço para compreender a noção filosófica de identidade pessoal ao longo do tempo. O procedimento para atingir tal compreensão é o de analisar e discutir as principais soluções, encontradas na literatura, que foram propostas para o problema da identidade pessoal. Este problema é descrito como a dificuldade de fundamentar e explicar a nossa crença de que uma pessoa em um dado momento de sua vida e ela em um outro momento são a mesma pessoa, a despeito das grandes alterações biopsicossociais pelas quais ela passa. A primeira solução proposta para este problema é aquela que centra a identidade pessoal em critérios substanciais, que podem ser físicos ou metafísicos. A segunda solução analisada é aquela que recorre à noção de continuidade, seja física, seja psicológica, para buscar explicar como as pessoas permanecem as mesmas ao longo do tempo. Uma terceira solução investigada propõe o entendimento do problema em questão como um problema passível de ser resolvido pela análise linguístico-conceitual; nesta parte, discutimos as seguintes idéias: concepção cética de identidade pessoal, auto-referência, auto-consciência e perspectiva de primeira pessoa. E, por fim, utilizando as noções de auto-organização e de emergência, discutimos as possíveis contribuições da sistêmica na busca de uma solução para o problema. / Abstract: This work consists of an effort to understand the philosophical notion of personal identity over time. The means to reach this understanding is to analyse and to discuss the most important solutions found in the literature that were proposed to the problem of personal identity. This problem is described as the difficulty of grounding and explaining our belief that a person in a given moment of her life and herself in another moment are one and the same person, despite all the great biopsychosocial changes which she undergoes. The first proposed solution to this problem makes substantial criteria, whether physical or metaphysical, central to personal identity. The second solution appeals to the notion of continuity, whether physical or psychological, to explain how people remain the same over time. A third solution suggests that the problem can be solved through linguistic-conceptual analysis; here, we discuss such ideas as the sceptical conception of personal identity, selfreference, self-consciousness and the first-person perspective. And, finally, with the help of the notions of self-organization and emergence, we discuss possible contributions of systemic theory to solving the problem. / Mestre

Different studies have shown that faces seen with a direct gaze (creating eye contact) are more likely to be recognized than faces seen with a laterally deviated gaze. The present work was aimed at determining underlying processes of this gaze direction effect. More precisely, whether this effect was due to a more elaborated encoding of faces with direct gaze because of the social importance of the eye contact was tested. Results obtained showed that the gaze direction effect is a highly sensitive effect which influence on memory for faces is probably more incidental than previously hypothesized./ Différentes études ont montré que les visages vus avec un regard direct (créant un contact visuel) ont plus de chance dêtre reconnus que les visages vus avec un regard dévié latéralement. Ce travail avait pour but de déterminer la nature des processus sous-jacents à cet effet de la direction du regard. Plus précisément, nous avons testé lhypothèse dun encodage plus élaboré des visages avec un regard direct dû à la signification sociale du contact visuel. Les résultats obtenus ont montré que leffet de la direction du regard est un effet très sensible dont linfluence sur la mémoire pourrait être plus incidente que ce qui avait été proposé dans la littérature.

Mindfulness training cultivates momentary awareness, a form of attention directed to non-evaluative, immediate sensation. This form of attention stands in contrast to a more temporally extended awareness, which allows for the evaluative organization of experience into a personal narrative. The neural mechanisms underlying such awareness, and their role in regulating emotions, are poorly understood. Thus, in three functional magnetic resonance imaging (fMRI) experiments, I explored the thesis that momentary and extended awareness represent dissociable modes of self-reference, with momentary self-reference reducing ruminative elaboration of events by biasing attention towards interoceptive signals from the body. I compared individuals who were randomly-assigned to either an 8-week Mindfulness-Based Stress Reduction (MBSR) training course against a waitlisted group (Controls). Three distinct studies examined the impact of Mindfulness on: 1) the contrast between explicitly directed momentary and extended self referential processing; 2) reactions to an induced sadness challenge; and 3) the contrast between interoceptive (breath-monitoring) and exteroceptive (visual) attention. In all three studies MBSR led to a shift in neural activity away from cortical midline structures, such as the medial prefrontal and posterior cingulate cortices, to predominantly right-lateralized viscerosomatic structures, and specifically the insular cortex. Cortical midline activity is thought to support habitual patterns of evaluation, and stands as the neural correlate of a narrated, extended self, while right-lateralized insula activity is thought to represent the recurrent integration of present moment context, the neural correlate of the momentary self. These data revealed that MBSR may enhance the distinction between momentary and extended self-reference, reducing cortical midline responses and recruiting a novel, right-lateralized viscerosomatic network. Additionally, MBSR graduates demonstrated reduced emotional reactivity to a film-based sadness mood induction, reducing cortical midline activity and inhibition of the right insula. Moreover, the MBSR group demonstrated enhanced right middle insula recruitment during the monitoring of sensory experience associated with breath monitoring, a core mindfulness practice. The data from this final study also suggest that MBSR promoted an integration of posterior insular sensory representations with anterior insular subjective representations of present moment status. Preserved viscerosomatic activity in the face of emotional challenge may be a predictor of enhanced well-being following mindfulness training.

L'objectif de cette thèse était la modélisation et la démonstration expérimentale des fonctionnalités de lecture et écriture d'une nouvelle structure de mémoire magnétoresistive à accès aléatoire thermiquement assistée, la MRAM autoréférencée. L'empilement magnétique de la MRAM autoréférencée s'obtient à partir de celui de la MRAM thermiquement assistée en retirant la couche antiferromagnétique de référence, remplaçant de ce fait la couche de référence piégée par une couche libre la couche de lecture. En commutant indirectement l'aimantation de la couche de lecture par le biais d'un champ externe, la direction d'aimantation de la couche de stockage piégée, et ainsi le niveau logique stocké, peut être mesuré in-situ. Grace à la possibilité de programmer individuellement les deux couches magnétiques, la MRAM autoréférencée peut être considérée comme une unité logique magnétique, combinant la fonctionnalité mémoire avec la logique comparative dans un même dispositif, ce qui ouvre de nouveau champs d'applications. La fonctionnalité des modes de lecture et d'écriture de la MRAM autoréférencée ont été démontrées expérimentalement sur un premier jeu d'échantillons. Cependant, les champs requis se sont avérés être incompatible avec une application dans un produit industriel fonctionnel. Dans le but d'optimiser les champs requis pour l'écriture et la lecture, un modèle macrospin, inspiré du modèle de Stoner-Wohlfarth de retournement de l'aimantation, a été développé. En introduisant les phénomènes de couplages magnétostatiques, RKKY et d'échange entre matériaux ferromagnetiques et antiferromagnétiques, une forme générale de l'énergie applicable à n'importe quel empilement magnétique MRAM a été obtenue. Un mode d'écriture à basse amplitude de champ, basé sur le couplage magnétostatique entre les couches de lecture et de stockage, a été prédit par le modèle puis démontré expérimentalement sur un nouveau lot d'échantillons. Un excellent accord a été obtenu entre le modèle et les mesures expérimentales. Afin d'étudier la reproductibilité de l'écriture, l'influence de l'activation thermique a été introduite par le calcul des barrières d'énergies reliées aux transitions magnétiques effectuées lors de l'écriture, puis comparée aux mesures expérimentales de la probabilité d'écriture d'un nouveau lot d'échantillons. Une fois encore, un excellent accord a été obtenu entre le modèle et l'expérience. A l'aide du modèle développé et validé, une roadmap définissant les empilements magnétiques permettant de conserver des champs de fonctionnement faible pour des points mémoires jusqu'à 45 nm a été établie. En raison de limitations technologiques fondamentales dans les MRAM commutées par champ, il est apparu indispensable d'augmenter la capacité de stockage individuelle de chaque point mémoire pour atteindre de plus grande densité de stockage. Une nouvelle méthode de stockage angulaire exploitant la mobilité de l'aimantation de la couche de lecture a été explorée. A l'aide du modèle développé précédemment des échantillons adéquat ont été produits et ont permis de démontrer expérimentalement une capacité de stockage allant jusqu'à 4 bits par point mémoire individuel. Cependant, les champs de fonctionnement requis se sont avérés être bien supérieurs à ce qui est compatible avec une application industrielle. A l'aide du modèle, une nouvelle méthode d'écriture a été proposée et a permis d'établir une seconde roadmap vers le nœud technologique de 45 nm. Des structures miroirs à double barrières ont ensuite été étudiées, avec une démonstration expérimentale de faisabilité de leur fabrication, ainsi que de leurs fonctionnalités. Plus particulièrement, un mode d'écriture à faible champ, similaire à celui observé dans les MRAM autoréférencées à simple barrière, a été obtenu. Enfin, l'adaptation du stockage angulaire à ces structures miroirs a été modélisée, aboutissant à la proposition d'une méthode permettant de stocker jusqu'à 8 bits par point mémoire. / The goal of this thesis was to model and demonstrate experimentally the read and write functionalities of a new thermally assisted magnetic random access memory structure, the self-referenced MRAM. The self-referenced MRAM stack is obtained from the thermally assisted MRAM one by removing the reference antiferromagnetic, effectively replacing the pinned reference layer by a free layer: the sense layer. By remotely switching the sense layer magnetization, by means of an external field, the storage layer magnetization direction, and as such the stored bit state, can be probed in-situ. Due the possibility to program both magnetic layers individually, self-referenced MRAM can be operated as a Magnetic Logic Unit, combining in-stack the storage and exclusive-or logic functions and thereby opening new application ranges. The read and write functionality of self-referenced MRAM were experimentally demonstrated on a first batch of samples. However, the field requirements were found to be higher than the target requirements for fully functional industrial products. In order to optimize the read and write field requirements, we developed a macrospin model based on the Stoner-Wohlfarth model of magnetization reversal. By introducing magnetostatic, RKKY and ferromagnet/antiferromagnet exchange coupling phenomena, we calculated a general form of the energy for any type of MRAM magnetic stack. A previously proposed highly efficient switching mode, relying on the magnetostatic interactions between the sense and the storage layer, was effectively predicted by the model and experimentally demonstrated in new samples. An excellent agreement was obtained between the model and the experimental results. Increasing the stiffness of the storage layer was found to be critical in order to minimize the read field requirements at decreasing patterning dimensions. Material developments were performed to maximize the RKKY coupling in the synthetic ferrimagnet storage layer. In order to study the reproducibility of the write operation, the influence of thermal activation was modelled by calculating energy barriers and transition paths and compared with on-the-fly measurements of switching probabilities on the new set of samples with a stiffer storage layer. Again, an excellent agreement was obtained between the model and the experiments. Based on the model developed, we built a roadmap describing the magnetic stack to use, that allows a downscaling of the self-referenced MRAM down to 45 nm while conserving manageable field requirements. Due to fundamental limitations in field-induced switching MRAM technology, reaching higher densities was found to require increasing the individual storage capacity of each MTJ, i.e. storing multiple bits per unit cell. A new angle-based storage method taking advantage of the sense layer free magnetization was investigated. Using the magnetic model developed previously, suitable samples were designed and allowed to experimentally demonstrate up to 4 bits per single MTJ. The field requirements were however found to be substantially higher than those compatible with a fully functional product. A new write method, predicted by the model, was investigated and exploited in the building of a second roadmap down to 45 nm. Mirrored dual barrier structures were then studied, with the experimental demonstration of their manufacturability and functionality. Notably, a highly efficient write mechanism similar to that observed in single barrier self-referenced MRAM was obtained. Finally, the adaptation of angle-based storage to these dual barrier devices was modeled, leading to the proposition of a method to store up to 8 bits per single cell.

Made available in DSpace on 2014-06-11T19:25:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-03-30Bitstream added on 2014-06-13T20:53:23Z : No. of bitstreams: 1 viana_ca_me_mar.pdf: 1931238 bytes, checksum: 0ab6d79e4636a04ef562ac6fc8ec4c9b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho consiste num esforço para compreender a noção filosófica de identidade pessoal ao longo do tempo. O procedimento para atingir tal compreensão é o de analisar e discutir as principais soluções, encontradas na literatura, que foram propostas para o problema da identidade pessoal. Este problema é descrito como a dificuldade de fundamentar e explicar a nossa crença de que uma pessoa em um dado momento de sua vida e ela em um outro momento são a mesma pessoa, a despeito das grandes alterações biopsicossociais pelas quais ela passa. A primeira solução proposta para este problema é aquela que centra a identidade pessoal em critérios substanciais, que podem ser físicos ou metafísicos. A segunda solução analisada é aquela que recorre à noção de continuidade, seja física, seja psicológica, para buscar explicar como as pessoas permanecem as mesmas ao longo do tempo. Uma terceira solução investigada propõe o entendimento do problema em questão como um problema passível de ser resolvido pela análise linguístico-conceitual; nesta parte, discutimos as seguintes idéias: concepção cética de identidade pessoal, auto-referência, auto-consciência e perspectiva de primeira pessoa. E, por fim, utilizando as noções de auto-organização e de emergência, discutimos as possíveis contribuições da sistêmica na busca de uma solução para o problema. / This work consists of an effort to understand the philosophical notion of personal identity over time. The means to reach this understanding is to analyse and to discuss the most important solutions found in the literature that were proposed to the problem of personal identity. This problem is described as the difficulty of grounding and explaining our belief that a person in a given moment of her life and herself in another moment are one and the same person, despite all the great biopsychosocial changes which she undergoes. The first proposed solution to this problem makes substantial criteria, whether physical or metaphysical, central to personal identity. The second solution appeals to the notion of continuity, whether physical or psychological, to explain how people remain the same over time. A third solution suggests that the problem can be solved through linguistic-conceptual analysis; here, we discuss such ideas as the sceptical conception of personal identity, selfreference, self-consciousness and the first-person perspective. And, finally, with the help of the notions of self-organization and emergence, we discuss possible contributions of systemic theory to solving the problem.