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Evolving Spatially Aggregated Features for Regional Modeling and its Application to Satellite ImageryKriegman, Sam 01 January 2016 (has links)
Satellite imagery and remote sensing provide explanatory variables at relatively high resolutions for modeling geospatial phenomena, yet regional summaries are often desirable for analysis and actionable insight. In this paper, we propose a novel method of inducing spatial aggregations as a component of the statistical learning process, yielding regional model features whose construction is driven by model prediction performance rather than prior assumptions. Our results demonstrate that Genetic Programming is particularly well suited to this type of feature construction because it can automatically synthesize appropriate aggregations, as well as better incorporate them into predictive models compared to other regression methods we tested. In our experiments we consider a specific problem instance and real-world dataset relevant to predicting snow properties in high-mountain Asia.
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The Effects of Pet Ownership on Physical Well-Being in Older AdultsPohnert, Tami 01 January 2010 (has links)
A large percentage of Americans own pets which may impact their health. This study examines pet ownership’s effect on well being in older adults looking at race/ethnicity. A sample of 6,565 older adults (>60) was selected from the Third National Health and Nutrition Survey. Pet owners comprised 28.3% of the sample. The theories of symbolic interaction and social integration were used to examine pet ownership’s effect on physical components of well-being. The descriptive results showed statistically significant differences in age, education, income, and marital status between pet owners and non-pet owners. Pet owners were younger, more educate, higher income and married. Similar results were found for Caucasians, African Americans and Mexican Americans. Logistic regression for the entire sample revealed pet owners were more likely to have a positive self perception of health, normal blood pressure, improved function, less chronic conditions, improved function and more falls. Multiple regression revealed pet owners had more hospital stays, but fewer physician visits and nursing home stays than non-pet owners. When examined by race/ethnicity differences were found between pet owners and non-pet owners that differed from the general sample results. This research revealed that pets overall positively impact their owners’ health but it appears to differ based on race/ethnicity. Further research is needed on pet ownership’s effect on older adults specifically in regards to race.
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Abstraction discovery and refinement for model checking by symbolic trajectory evaluationAdams, Sara Elisabeth January 2014 (has links)
This dissertation documents two contributions to automating the formal verification of hardware – particularly memory-intensive circuits – by Symbolic Trajectory Evaluation (STE), a model checking technique based on symbolic simulation over abstract sets of states. The contributions focus on improvements to the use of BDD-based STE, which uses binary decision diagrams internally. We introduce a solution to one of the major hurdles in using STE: finding suitable abstractions. Our work has produced the first known algorithm that addresses this problem by automatically discovering good, non-trivial abstractions. These abstractions are computed from the specification, and essentially encode partial input combinations sufficient for determining the specification’s output value. They can then be used to verify whether the hardware model meets its specification using a technique based on and significantly extending previous work by Melham and Jones [2]. Moreover, we prove that our algorithm delivers correct results by construction. We demonstrate that the abstractions received by our algorithm can greatly reduce verification costs with three example hardware designs, typical of the kind of problems faced by the semiconductor design industry. We further propose a refinement method for abstraction schemes when over- abstraction occurs, i.e., when the abstraction hides too much information of the original design to determine whether it meets its specification. The refinement algorithm we present is based on previous work by Chockler et al. [3], which selects refinement candidates by approximating which abstracted input is likely the biggest cause of the abstraction being unsuitable. We extend this work substantially, concentrating on three aspects. First, we suggest how the approach can also work for much more general abstraction schemes. This enables refining any abstraction allowed in STE, rather than just a subset. Second, Chockler et al. describe how to refine an abstraction once a refinement candidate has been identified. We present three additional variants of refining the abstraction. Third, the refinement at its core depends on evaluating circuit logic gates. The previous work offered solutions for NOT- and AND-gates. We propose a general approach to evaluating arbitrary logic gates, which improves the selection process of refinement candidates. We show the effectiveness of our work by automatically refining an abstraction for a content-addressable memory that exhibits over-abstraction, and by evaluating some common logic gates. These two contributions can be used independently to help automate the hard- ware verification by STE, but they also complement each other. To show this, we combine both algorithms to create a fully automatic abstraction discovery and refinement loop. The only inputs required are the hardware design and the specification, which the design should meet. While only small circuits could be verified completely automatically, it clearly shows that our two contributions allow the construction of a verification framework that does not require any user interaction.
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Incidences subjectives de l'annonce du pronostic létal / Subjective effects of announcement of a lethal prognosticBernard Lemonnier, Sophie 30 March 2012 (has links)
S’entendre annoncer, lors d’une consultation médicale, que la mort est proche, n’est pas sans effet subjectif. Effroi et traumatisme : violence faite à cette illusion d’immortalité protectrice qui soutient le sujet dans sa quotidienneté, ouverture faite sur le gouffre de la déréliction. La clinique que l’on rencontre dans une unité de soins palliatifs met en évidence les effets subjectifs, trop souvent délétères, d’une telle annonce. C’est à partir de celle-ci que se déploie cette interrogation concernant le sujet et ce qu’il parvient à faire –ou non– de cette annonce. Nous serons alors amenés à rendre compte de ce que la mort réelle, annoncée du lieu de l’Autre, a cet effet de produire une néantisation de la fonction symbolique qu’il supporte, en ce que son manque vient subitement à manquer. La clinique propre aux soins palliatifs montre alors les incidences subjectives d’une telle vacillation et les possibles recours du sujet dans ses tentatives pour pallier au défaut del’Autre. / Agree announce during a medical consultation, that death is near, is not without subjective effect. Fear and trauma: violence against the illusion of immortality, which supports the protective subject his everyday life, opening made on the gulf of abandonment. The clinic encountered in a palliative care unit highlights the subjective effects, often deleterious, suchan announcement. It is from this that unfolds this question on the subject and he manages to do-or not-of this announcement. We will then be brought to account for what the actual death, announced the place of the Other, this has to produce an annihilation of the symbolic function that it supports, in that its lack is suddenly missing. The clinic-specific palliative care then shows the implications of such a subjective vacillation and the possible use of the subject inhis attempts to overcome the lack of the Other.
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Automatic verification of cryptographic protocols : privacy-type properties / Vérification automatique des protocoles cryptographiques : propriétés d'équivalenceCheval, Vincent 03 December 2012 (has links)
Plusieurs outils ont été développé pour vérifier automatiquement les propriétés de sécurité sur des protocoles cryptographiques. Jusqu'à maintenant, la plupart de ces outils permettent de vérifier des propriétés de trace (ou propriétés d'accessibilité) tel que le secret simple ou l'authentification. Néanmoins, plusieurs propriétés de sécurité ne peuvent pas être exprimés en tant que propriété de trace, mais peuvent l'être en tant que propriété d'équivalence. L'anonymat, la non-tracabilité ou le secret fort sont des exemples classique de propriété d'équivalence. Typiquement, deux protocoles P et Q sont équivalent si les actions d'un adversaire (intrus) ne lui permettent pas de distinguer P de Q. Dans la littérature, plusieurs notions d'équivalence ont été étudiés, par exemple l'équivalence de trace ou l'équivalence observationnelle. Néanmoins, ces équivalences se relèvent être très difficiles à démontrer , d'où l'importance de développer des outils de vérification automatique efficaces de ces équivalences. Au sein de cette thèse, nous avons dans un premier temps travaillé sur une approche reposant sur des techniques de résolution de contraintes et nous avons créé un nouvel algorithme pour décider l'équivalence de trace entre deux protocoles pouvant contenir des conditionnelles avec branches "else", et pouvant également être non-déterministe. Cet algorithme a été appliqué sur des exemples concrets comme le "Private authentification protocol" ainsi que le "E-passport protocol". Cette thèse propose également des résultats de composition pour l'équivalence de trace. En particulier, nous nous sommes intéressé à la composition parallèle de protocoles partageant certains secrets. Ainsi dans cette thèse, nous avons démontré que, sous certaines conditions, la composition parallèle de protocoles préserve les propriétés d'équivalence. Ce résultat fut appliqué au "E-passport protocol". Enfin, cette thèse présente une extension à l'outil de vérification automatique ProVerif afin de démontrer automatiquement plus de propriétés d'équivalence. Cette extension a été implémenté au sein de ProVerif ce qui a permis de démontrer la propriété d'anonymat pour le "Private authentification protocol" . / Many tools have been developed to automatically verify security properties on cryptographic protocols. But until recently, most tools focused on trace properties (or reachability properties) such as authentication and secrecy. However, many security properties cannot be expressed as trace properties, but can be written as equivalence properties. Privacy, unlinkability, and strong secrecy are typical examples of equivalence properties. Intuitively, two protocols P, Q are equivalent if an adversary can not distinguish P from Q by interacting with these processes. In the literature, several notions of equivalence were studied, e.g. trace equivalence or a stronger one, observational equivalence. However, it is often very difficult to prove by hand any of these equivalences, hence the need for efficient and automatic tools. We first worked on an approach that rely on constraint solving techniques and that is well suited for bounded number of sessions. We provided a new algorithm for deciding the trace equivalence between processes that may contain negative tests and non-determinism. We applied our results on concrete examples such as anonymity of the Private Authentication protocol and the E-passport protocol. We also investigated composition results. More precisely, we focused on parallel composition under shared secrets. We showed that under certain conditions on the protocols, the privacy type properties are preserved under parallel composition and under shared secrets. We applied our result on the e-passport protocol. At last this work presents an extension of the automatic protocol verifier ProVerif in order to prove more observational equivalences. This extension have been implemented in ProVerif and allows us to automatically prove anonymity in the private authentication protocol.
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Transmission de l'information et complexité des activités de populations neuronalesBlanc, Jean-luc 22 February 2012 (has links)
Dans cette thèse, nous abordons les problèmes de la transmission et du traitement de l'information par les assemblées de neurones, du point de vue de l'approche inter-disciplinaire des systèmes complexes en nous référant principalement aux formalismes de la théorie de l'information et de la théorie des systèmes dynamiques. Dans ce contexte, nous nous focalisons sur les mécanismes de représentation de l'information sensorielle par les activités neuronales à travers le codage neuronal. Nous explorons la structure de ce code, à plusieurs échelles grâce à l'étude de différents signaux électrophysiologiques issus de populations de neurones (signaux unitaires, LFP et EEG). Sur le plan méthodologique, nous avons implémenté différents indices permettant d'extraire objectivement l'information des activités neuronales, mais également d'en caractériser la dynamique sous-jacente à partir de séries temporelles de taille finie (le taux d'entropie). Nous avons également étudié un indicateur peu utilisé (le taux d'information mutuelle), qui permet de quantifier l'auto-organisation et les relations de couplage entre deux systèmes. Grâce à des approches théoriques et numériques, nous analysons les propriétés caractéristiques de ces indices et proposons leur utilisation dans le cadre de l'étude des systèmes neuronaux. Ce travail permet de caractériser la complexité de différentes activités neuronales associées aux dynamiques de transmission de l'information. / In this thesis, we address the problem of transmission and information processing by neuronal assemblies, in terms of the interdisciplinary approach of complex systems by referring mainly to the formalisms of information theory and dynamical systems. In this context, we focus on the mechanisms underlying sensory information representation by neuronal activity through neural coding. We explore the structure of this code under several scales through the study of different neuronal population electrophysiological signals (singel unit, LFP and EEG). We have implemented various indices in order to extract objectively information from neural activity, but also to characterize the underlying dynamics from finite size time series (the entropy rate). We also defined a new indicator (the mutual information rate), which quantifies self-organization and relations of coupling between two systems. Using theoretical and numerical approaches, we analyze some characteristic properties of these indices and propose their use in the context of the study of neural systems. This work allows us to characterize the complexity of different neuronal activity associated to information transmission dynamics.
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Dynamique commune des fractals de rauzy de même matrice d' incidence.Sellami, Tarek 25 June 2012 (has links)
On sait que la matrice d'incidence associée à une substitution ne suffit pas pour déterminer complètement le système dynamique associé, même dans des cas très simples, il existe plusieurs substitutions associées à une même matrice car il existe de nombreux mots ayant le même abélianisé. Dans cette thèse, on étudie les points communs de deux lignes brisées associées à deux substitutions $sigma_1$ et $sigma_2$ irréductibles unimodulaires de type Pisot qui ont la même matrice d'incidence. On identifie les points communs de ces deux lignes brisées à partir d'un algorithme. On montre ainsi que l'intersection de ces deux lignes brisées est aussi une ligne brisée associée au point fixe d'une nouvelle substitution. On montre plus précisément que si $sigma_1$ vérifie la conjecture Pisot et $0$ est un point intérieur à son fractal de Rauzy alors ces points communs peuvent être engendrés par une substitution définie sur un alphabet appelé alphabet des paires équilibrées. Cette substitution est obtenue à partir d'un algorithme, l'algorithme des paires équilibrées. On obtient ainsi l'intersection des intérieurs des deux fractals de Rauzy. En prenant la clôture de cet ensemble on obtient un ensemble substitutif. La condition que $0$ est un point intérieur au fractal de Rauzy associé à la substitution $sigma_1$ nous permet de montrer que l'intersection des deux fractals de Rauzy est de mesure positive. Dans une deuxième partie du travail on s'intéresse à l'étude de la frontière du fractal de Rauzy. Le fractal de Rauzy est dit fractal mais c'est en fait sa frontière qui est fractale. / The matrix of a substitution is not sufficient to completely determine the dynamics associated with it, even in the simplest cases since there are many words with the same abelianization. In this paper we study the common points of the canonical broken lines associated with two different irreducible Pisot unimodular substitutions σ1 and σ2 having the same incidence matrix. We prove that if σ1 verifies the Pisot conjecture and 0 is an inner point to the Rauzy fractal associated with the substitution σ1 then these common points can be generated with a substitution on an alphabet of so-called balanced pairs, and we obtain in this way the intersection of the interior of two Rauzy fractals.
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Možnosti využití symbolického rámce v projektovém vyučování / Application possibilities of symbolical frame in project learningHořavová, Kateřina January 2012 (has links)
The thesis explores possibilities of linking the symbolic frameworks and project method into a functional complex, which would enrich education. The reason of connection can be mainly found in strengthening the internal motivation of pupils and in bringing themes coming from the world of children into education as well.
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Etymologická analýza označení barev a úsloví barvy obsahujících / Etymological analysis of colour names and related idiomsHořejší, Anna January 2014 (has links)
TITLE: The etymological analysis of colour names and related idioms AUTHOR: Anna Hořejší DEPARTMENT: Department of the French language and literature SUPERVISOR: Mgr. Jiří Jančík ABSTRACT: This diploma thesis concerns the etymological analyses of colour names in the French language and related idioms. In the theoretical part we present the basic linguistic terminology necessary for the accomplishment of the etymological analyses; the practical part concerns the analyses itself. The objective of the thesis is to deeply analyze the six basic colours both from the etymological and symbolic point of view. Furthermore, the thesis concerns the etymological analyses of colours the names of which are to some extend specific and remarkable. We talk about colours like: fox tail, bonbon, the Berlin blue, tea, khaki, pearl or snow, divided into groups according to the word they contain (colours containing a name of an animal, food, liquid, material, the place of origin, etc.). These colours are examined not only etymologically; we are also interested in the reason for which they are called so. In the last part of the thesis we scrutinize also idioms containing a name of a colour; we talk about idioms like white night, yellow danger, to be bad like a red donkey, cordon bleu or green tongue. In this case, our goal is to...
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Factions and class fictions : investigating narratives of resistance in representations of lower-class men in post-War British literature in the New Wave & Thatcherite years, &, If I'm ever to find these trees meaningful I must have you by the thighs : a collection of poemsSmith, Wayne January 2015 (has links)
This thesis combines an academic investigation and creative writing practice in an attempt to understand the politics at work within mainstream notions of working-class masculine identity, and the role of literature in these discourses. Beginning with an academic analysis, the formulations and intersection of class and masculinity are outlined, explicating how systems, implemented by the middle-class creation of values, form social narratives whereby men of certain settings with associative lifestyles and practices, are privileged over other less valued groups of men. In this respect, its concerns are primarily with the socio-symbolic. Locating this discourse within an Aristotelian dichotomy of the mind and the body, this theoretical position is then applied in the scrutiny of six mainstream fictional narratives of two historic periods, each originally held to be politically subversive. In calling to question the validity of these original claims, further questions are raised regarding the nature of the mainstream fictional narrative at large, and whether it is an effective way of representing the politics of working-class identity, or whether, by its nature, it serves to reproduce its working-class characters as fixed subjects, immovable from their positions in a stable class system. This line of inquiry is then further explored in the deconstruction of my own creative work, in which I initially sought to represent the concerns of my own working-class heritage. The resulting issues raised with respect to mainstream, linear narrative leading to the investigation of other potential forms of representation for the working-class male, culminating in the exploration of my own shifting identity in a non-linear, multi-directional collection of poetry.
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