Ten experimentally naive children between the ages of six and eight served in three generalized imitation experiments using symbolic models. Subjects were presented videotaped behaviors to imitate via closed circuit television, and their responses were mechanically defined, recorded, and reinforced in an effort to control social influences from the presence of the experimenter. In Experiment 1, imitation of three behaviors was reinforced and imitation of a fourth behavior was never reinforced for four subjects. Two other subjects received noncontingent reinforcement. The following independent variables were tested: (1) the presence and absence of an experimenter, (2) instructions to "Do that," and (3) contingent and noncontingent reinforcement. Results of Experiment 1 demonstrated the apparatus could be used to produce and maintain generalized imitation, even in the absence of the experimenter, so long as differential reinforcement was available. ''Do that'' instructions were not necessary, and the presence of the experimenter served to maintain imitation when contingent reinforcement was not available. In Experiment 2, four subjects produced generalized imitation in the absence of both a n experimenter and any instructions with two reinforced and two nonreinforced imitations. Using the same four subjects in Experiment 3, congruent, incongruent, and "Do what you want" instructions given before sessions demonstrated that instructions could override the effect of reinforcers or produce differential responding in most subjects. When given a choice to imitate or not imitate, subjects continued generalized imitation. The data tend to support the theory that imitation is itself a response class, and the effect of instructions is to divide that response class into a class of imitated responses and a class of instruction-following responses. The influence of instructions, even in the absence of an adult experimenter, was obvious.

Les systèmes réactifs sont modélisés avec différents types d'automates, tels que les systèmes de transitions symboliques à entrée sortie (IOSTS). L'exécution symbolique d'un IOSTS permet la génération de cas de test qui peuvent être exécutés sur une implantation concrète, afin de déterminer si elle est conforme à son modèle. Dans ce document, nous étendons les IOSTS avec des appels de fonctions utilisateur et analysons leur impact sur le système entier et viceversa. Cette thèse comble l'écart entre une approche basée sur le modèle où les fonctions utilisateur sont abstraites et une approche basée sur le code où les petits morceaux de code sont considérés séparément, indépendamment de la façon dont ils sont combinés. Selon le niveau de connaissance que nous avons sur ces fonctions, elles sont modélisées soit par une spécification complète, soit par une spécification partielle, soit juste comme des boîtes noires fournies sans aucune connaissance. Premièrement, lorsque les fonctions sont partiellement connues, nous utilisons des bouchons définis par des tables contenant des tuples représentatifs des données d'entrée/sortie. L'approche proposée emprunte au test "concolic", l'idée de mélanger l'exécution symbolique avec l'information obtenue à partir d'exécutions concrètes des fonctions (tables). Deuxièmement, si l'utilisateur est prêt à fournir d'autres spécifications, il serait intéressant d'utiliser des représentations plus complètes pour les fonctions. Par conséquent, nous proposons d'abstraire des comportements des fonctions par des contrats pré/post. Ensuite, nous étendons l'exécution symbolique en analysant les fonctions via leurs contrats. Enfin, lorsque les fonctions appelées sont complètement inconnues, nous présentons une approche pour extraire de nouveaux contrats pour eux en explorant les contraintes issues de l'exécution symbolique de l'IOSTS. De tels contrats reflètent les contraintes des fonctions qui rendent possible un certain comportement (exigence). / Reactive systems are modeled with various kinds of automata, such as Input Output Symbolic Transition Systems (IOSTS). Symbolic execution over an IOSTS allows test cases generation that can be executed on a concrete implementation, in order to determine whether it is conforming to its model. In this dissertation, we aim at extending the IOSTS framework with explicit user-defined function calls and analyze their impact on a whole system and vice-versa. The thesis bridges the gap between a model-based approach in which user-defined functions are abstracted away and a code-based approach in which small pieces of code are considered separately regardless of the way they are combined. According to the level of knowledge we have about these functions, they are modeled either by a complete specification, a partial specification, or even just as black-boxes provided without any knowledge. First, when functions are partially known, we use function stubs defined by tables containing representative input/output data tuples. The proposed approach borrows from concolic testing, the idea of mixing symbolic execution with information obtained from instrumented concrete executions (function tables). Second, if the user is willing to provide further specifications, it would be interesting to use more complete representations for called functions. Hence, we propose to abstract function behaviors by means of pre/post contracts. Then we extend symbolic execution by analyzing the functions through their contracts. Finally, when called functions are completely unknown, we present an approach to extract new contracts for them by exploring constraints coming from the IOSTS symbolic execution. Such contracts reflect constraints on the functions that make some behavior (requirement) feasible.

Cette thèse traite de problèmes d'intégration symbolique en calcul formel. L'objectif principal est de mettre au point des algorithmes permettant de calculer rapidement des fonctions qui sont présentées sous la forme d'intégrales de contour dépendant d'un paramètre.On commence par aborder le problème du calcul de l'intégrale d'une fraction rationnelle bivariée par rapport à l'une de ses variables. Le résultat est alors une fonction algébrique qui s'exprime comme une somme de résidus de l'intégrande. On met au point deux algorithmes qui calculent efficacement un polynôme annulateur pour chacun des résidus, et ensuite pour la somme, ce qui donne accès à un polynôme annulateur pour l'intégrale elle-même.Ces algorithmes s'appliquent presque directement au calcul d'un polynôme annulateur pour la diagonale d'une fraction rationnelle bivariée, c'est-à-dire la série univariée obtenue à partir du développement en série d'une fraction rationnelle bivariée en ne gardant que les coefficients diagonaux. En effet, ces diagonales peuvent s'écrire comme des intégrales de fractions rationnelles. Dans une autre application, on donne un nouvel algorithme pour le développement des séries génératrices de plusieurs familles de marches unidimensionnelles sur les entiers. Il repose sur une analyse fine des tailles des équations algébriques et différentielles satisfaites par ces séries.Dans un second temps, on s'intéresse au calcul de l'intégrale d'un terme mixte hypergéométrique et hyperexponentiel. Cette fois-ci le résultat est une suite polynomialement récursive. On élabore une méthode pour mettre sous forme normale les divers décalages d'un terme donné. Ceci permet d'appliquer la méthode du télescopage créatif par réductions pour calculer efficacement une récurrence à coefficients polynomiaux satisfaite par l'intégrale. / In this thesis, we provide solutions to some symbolic integration problems in computer algebra. The main objective is to effectively and efficiently compute functions that appear as contour integrals depending on one parameter.First, we consider the computation of the integral of a bivariate rational function with regard to one of the variables. The result is then an algebraic function that can be expressed as a sum of residues of the integrand. We design two algorithms that efficiently compute an annihilating polynomial for each residue, and then for their sum, which yields an annihilating polynomial for the integral itself.These algorithms apply almost directly to the computation of an annihilating polynomial for the diagonal of a rational function, that is, the univariate power series obtained from the expansion of a bivariate rational function by only keeping the diagonal coefficients. Indeed, these diagonals can be written as integrals of rational functions. In another application, we give a new algorithm for the Taylor expansion of the generating functions for several families of unidimensional lattice walks. It relies on a fine analysis of the sizes of the algebraic and differential equations satisfied by these generating functions.Secondly, we consider integrals of mixed hypergeometric and hyperexponential terms. In this case, the result is a polynomially recursive sequence. We devise a method to rewrite the various shifts of a given term under a normal form. This allows us to apply the method of reduction-based creative telescoping in order to efficiently compute a recurrence with polynomial coefficients for the integral.

Cette thèse s'inscrit dans le domaine de la vérification de protocoles cryptographiques dans le modèle symbolique. Plus précisément, il s'agit de s'assurer à l'aide de méthodes formelles que de petits programmes distribués satisfont à des propriétés d'indistinguabilité, c'est-à-dire qu'un attaquant n'est pas capable de deviner quelle situation (parmi deux)il observe. Ce formalisme permet d'exprimer des propriétés de sécurité comme le secret fort, l'intraçabilité ou l'anonymat. De plus, les protocoles sont exécutés simultanément par un grand nombre d'agents, à plusieurs reprises si bien que nous nous heurtons très rapidement à des résultats d'indécidabilité. Dès lors, il faut ou bien tenir compte du nombre arbitraire de sessions et rechercher des méthodes de semi-décision ou identifier des classes décidables ;ou bien établir des procédures de décision pour un nombre fini de sessions. Au moment où nous avons commencé les travaux présentés dans cette thèse les outils de vérification de propriétés d'indistinguabilité pour un nombre borné de sessions ne permettaient de traiter que très peu de sessions :dans certains cas il était tout juste possible de modéliser un échange complet. Cette thèse présente des procédures de décision efficaces dans ce cadre. Dans un premier temps, nous établissons des résultats de petite attaque. Pour des protocoles déterministes nous démontrons qu'il existe une attaque si, et seulement s’il existe une attaque bien typée lorsque toute confusion entre les types des variables est évitée. De plus, nous prouvons que, lorqu'il existe une attaque l'attaquant peut la trouver en utilisant au plus trois constantes. Dans un second temps, nous traduisons le problème d'indistinguabilité en termes d'accessibilité dans un système de planification qui est résolu par l'algorithme du graphe de planification associé à un codage SAT. Nous terminons en confirmant l'efficacité de la démarche ,à travers l'implémentation de l'outil SAT-Equivet sa comparaison vis-à-vis des outils analogues. / This thesis presents methods to verify cryptographic protocolsin the symbolic model: formal methods allowto verify that small distributed programssatisfy equivalence properties.Those properties state that an attackercannot decide what scenario is beeing played.Strong secrecy, and privacy type properties, like anonymityand unlinkeability, can be modelled through this formalism.Moreover, protocols are executed simultaneouslyby an unbounded number of agents, for an unbounded numberof sessions,which leads to indecidability results.So, we have either to consider an arbitrary number of sessions,and search for semi-decision proceduresand decidable classes;or to establish decision procedures for a finite numberof sessions.When we started the work presented in this thesis,the existing equivalence checkers in the bounded modelwere highly limited. They could only handlea~very small number of sessions (sometimes no more than three).This thesis presents efficient decision proceduresfor bounded verification of equivalence properties.Our first step is to provide small attack results.First, for deterministic processes, there existsan attack if, and ony if, there is a well-typed attack,assuming that there is no confusion between variable types.Second, when there exists a flaw,the attacker needs at most three constants to find it.Then, our second step is to translatethe indistinguishability problem as a reachability problemin a planning system. We solve this second problemthrough planning graph algorithm and SAT encoding.In a final step, we present the implementation ofthe SAT-Equiv tool, which allows us to evaluate our approach.In particular, a benchmark with comparable tools provesthe efficiency of SAT-Equiv.

Jerome Skolnick’s (2011) "symbolic assailant" is a result of police attributing particular demeanor, gestures, language, and a style of dress to people they believed were most likely to commit violent crimes. The challenge became when police applied these characteristics to specific groups such as juveniles. Literature published before and after Skolnick (2011) indicated police were more likely to stop, arrest, interrogate, or surveille juveniles based on their demeanor, gestures, style of dress, lack of respect, deference to authority, the severity, and remorse for their offenses in addition to race. However, current research indicated race, gender, and Socioeconomic Status (SES) determined if police perceived juveniles as the symbolic assailant regardless of offense type. The current research also suggested the symbolic assailant is the foundation for related theories such as racial profiling and the “juvenile offender type-script.” Thus, this dissertation sought to determine if juveniles’ demeanor, gestures, race, gender, and offense type predicted if police perceived them as having characteristics analogous to the symbolic assailant. The researcher conducted a nonexperimental predictive correlational research design analyzing secondary data from Connecticut’s Effective Police Interactions with Youth’s Pretest Survey. The results showed weak to moderate relationships between the predictor and criterion variables such as police believed juveniles’ fidgeting, pacing, and mouthing off as signs of guilt indicated a weak relationship. The strongest predictor was a combination of race and offense type as the patrol officers responded all races and ethnicities were most likely to carry weapons equally in the past 30 days, which differed from the current symbolic assailant and related literature.

Notre travail de recherche propose d'envisager et d'étudier la danse en tant qu'activité constructrice de sens. Cette notion complexe a été diversement thématisée et explorée au cours de l'histoire de la danse, mais n'a que rarement été questionnée frontalement. Nous nous appuyons, pour mener à bien cette entreprise, sur les travaux de Susanne Langer, philosophe américaine du XXe siècle dont les ouvrages explorent la question du symbolique. Elle a développé au sujet de la danse une pensée originale, et élaboré des concepts proposant de circonscrire au mieux les processus symboliques à l'oeuvre dans les pratiques non discursives, et en particulier dans l'art. Nous choisissons, plutôt que d’aborder la danse d’un point de vue ontologique, comme une catégorie en soi sous laquelle seraient subsumés certains mouvements, de la considérer comme un événement, dont la survenue peut être intermittente. Approcher la danse sous cet angle offre la possibilité de rendre compte de son éventuelle apparition dans toute forme de mouvement, de la danse artistique à la danse festive, du mime au cinéma, du rite à la création numérique. Ce choix de ne pas réduire a priori le champ d'étude permet a posteriori de redessiner une frontière nette entre la danse et les autres formes de mouvement ou de pratiques corporelles. En effet, notre travail tend à réaffirmer la spécificité fondamentale de la danse, quels que soient les environnements, moments et corps dans lesquels elle apparaît – une spécificité tenant à ses processus symboliques uniques, et aux sens qu'elle peut ainsi construire ou faire émerger. / The aim of our work is to consider and study dance as a sense-Building activity. Sense is a complex notion, which has been variously conceptualized in the course of dance history but merely investigated. In order to do so, we build upon the works of Suzanne Langer, a 20th century American philosopher whose writings explore the concept of “symbol”. She elaborated an original thought about dance and came up with concepts that allowed her to circumscribe the symbolic processes happening during the non-Discursive practices, in art especially. Rather than looking at dance from an ontological point of view or as a category that gathers certain types of moves, we choose to study it as something that may appear on an intermittent basis. Watching dance this way makes it possible for us to give an account of the possibility of its emergence in any kind of movement, whether it happens in the course of artistic dance, festal dance, mime, cinema, rite or within a digital creation. This decision not to reduce a priori the field of study allows us to draw a posteriori a clear distinction between dance and any other kind of moves or bodily practices. Indeed, our work tends to claim the fundamental specificity of dance, whatever environments, moments or bodies in or during which it occurs – a specificity that may be explained by its unique symbolic processes and the meanings or senses it may build or give birth to.

Symbolic dynamics is a current interest in the area of anomaly detection, especially in mechanical systems.  Symbolic dynamics reduces the overall dimensionality of system responses while maintaining a high level of robustness to noise.  Rolling element bearings are particularly common mechanical components where anomaly detection is of high importance.  Harsh operating conditions and manufacturing imperfections increase vibration innately reducing component life and increasing downtime and costly repairs.  This thesis presents a novel way to detect bearing vibrational anomalies through Symbolic Aggregate Approximation (SAX) in the two-dimensional time-frequency domain.  SAX reduces computational requirements by partitioning high-dimensional sensor data into discrete states.  This analysis specifically suits bearing vibration data in the time-frequency domain, as the distribution of data does not greatly change between normal and faulty conditions. Under ground truth synthetically-generated experiments, two-dimensional SAX in conjunction with Markov model feature extraction is successful in detecting anomalies (> 99%) using short time spans (< 0.1 seconds) of data in the time-frequency domain with low false alarms (< 8%).  Analysis of real-world datasets validates the performance over the commonly used one-dimensional symbolic analysis by detecting 100% of experimental anomalous vibration with 0 false alarms in all fault types using less than 1 second of data for the basis of 'normality'. Two-dimensional SAX also demonstrates the ability to detect anomalies in predicative monitoring environments earlier than previous methods, even in low Signal-to-Noise ratios. / Master of Science

We model hyperbolic toral automorphisms by two types of Smale spaces; shifts of finite type and substitution tilings spaces. Smale spaces are dynamical systems with local hyperbolic product structure. In 1970, Bowen showed that an irreducible Smale space is a factor of a shift of finite type by showing that it has Markov partitions. Putnam extended Bowen's theorem by showing that every irreducible Smale space has a factor map that can be split into a s-bijective and u-bijective map; thereby better modelling a Smale space on its characterizing expanding and contracting spaces separately. In this thesis, we define two new constructions of Markov partitions for hyperbolic toral automorphisms inspired by the work of Adler, Weiss, and Praggastis. With one of the constructions, we investigate when a factor map from a shift of finite type to a hyperbolic toral automorphism can be written as a composition of a s-bijective and u-bijective map and we show that if such a splitting exists then the Markov partition must satisfy a Border Continuity condition. The second construction can be thought of as an explicit example of Putnam's theorem for the case of hyperbolic toral automorphisms whose defining matrix is in dimension 2 and has positive entries. We define a full splitting for all such hyperbolic toral automorphisms with one exception; the Arnold Cat map. / Graduate

Biometric identification uses individuals' characteristics to attempt to match a sample to a database of existing samples. An increasingly commonly used characteristic is the iris section of the eye, which is valued for its uniqueness among individuals and stability over time. One key concern with iris recognition systems is the time required to find a test sample's match in a database of subjects. This work considers methods for categorizing irises within a database, so that a search for a match to a test sample can be focused on the test sample's category. The main method for categorization used in this work is texton learning. Texton learning involves creating a vocabulary of features and determining how much of each feature a given sample has. Once images are represented by textons, they are clustered in an unsupervised process. Success of the system is assessed as its ability to take a previously unseen image from a subject and classify it the same as the database reference for the subject. This work improves upon the past applications of texton learning with more thorough experiments to determine the optimal number of textons and image clusters. This system also investigates different accuracy metrics, with this work detailing two key methods and their relative benefits. Additionally, more in depth analysis is given for potential time saving impacts for finding a database match. Beyond the improvements to texton learning, symbolic features (ethnicity and gender) have been incorporated into the categorization process using a probabilistic metric. This is an innovative combination of using the numerical representation of the iris along with demographic information.

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