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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.
21

A Class of Stochastic Petri Nets with Step Semantics and Related Equivalence Notions

Buchholz, Peter, Tarasyuk, Igor V. 15 January 2013 (has links)
This paper presents a class of Stochastic Petri Nets with concurrent transition firings. It is assumed that transitions occur in steps and that for every step each enabled transition decides probabilistically whether it wants to participate in the step or not. Among the transitions which what to participate in a step, a maximal number is chosen to perform the firing step. The observable behavior is defined and equivalence relations are introduced. The equivalence relations extend the well-known trace and bisimulation equivalences for systems with step semantics to Stochastik Petri Nets with concurrent transition firing. It is shown that the equivalence notions form a lattice of interrelations.
22

Clones sous-maximaux inf-réductibles

Grecianu, Andrei-Paul January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
23

Relações emergentes avaliadas em testes de transferência de função em pombos / Emergent relations evaluated in transfer of function tests in pigeons

Campos, Heloisa Cursi 06 December 2013 (has links)
Os resultados de Campos et al. (2011) indicaram a emergência de simetria, mas não de transitividade e equivalência em pombos com o procedimento go/no-go com estímulos compostos. O presente experimento investigou a formação de classes em testes de transferência de função após treino com o procedimento go/no-go com estímulos compostos. Quatro pombos foram treinados a responder aos estímulos compostos A1B1, A2B2, B1C1 e B2C2 e a não responder aos compostos A1B2, A2B1, B1C2 e B2C1. Posteriormente, os sujeitos foram treinados a responder em DRL 3 s a A1 e FR20 a A2. Testes de transferência de função apresentaram os estímulos de treino A1 e A2 e os estímulos de teste B1, C1, B2 e C2 para verificar se os sujeitos apresentariam taxa de respostas mais baixa a A1, B1 e C1 e mais alta a A2, B2 e C2. Os sujeitos apresentaram taxas de respostas mais baixas tanto para alguns estímulos do Conjunto 1 quanto para alguns estímulos do Conjunto 2. Portanto, os resultados dos testes de transferência de função não indicaram a formação de classes de equivalência após treino com o procedimento go/no-go com estímulos compostos em pombos. Sendo assim, independentemente dos testes empregados (testes das propriedades com o procedimento go/no-go com estímulos compostos ou teste de transferência de função), desempenhos emergentes não são verificados em pombos após treino com o procedimento go/no-go com estímulos compostos / Campos et al.s (2011) results indicated the emergence of symmetry, but not transitivity and equivalence with pigeons in a go/no-go procedure with compound stimuli. The present experiment investigated stimulus class formation in transfer of function tests after training in a go/no-go procedure with compound stimuli. Four pigeons were trained to respond to A1B1, A2B2, B1C1, and B2C2 compound stimuli e not to respond to A1B2, A2B1, B1C2, and B2C1 compounds. Subsequently, subjects were trained to respond in DRL 3 s to A1 and in FR20 to A2. Transfer of function tests presented the A1 and A2 training stimuli and the B1, C1, B2, and C2 test stimuli to verify if subjects would show a lower response rate to A1, B1, C1 and a higher response rate to A2, B2, C2. Subjects showed lower response rates to some Set-1 stimuli as well as to some Set-2 stimuli. Thus, the results of the transfer of function tests indicate that equivalence classes were not established after training with the go/no-go procedure with compound stimuli in pigeons. Therefore, regardless of the test used (tests of the properties with the go/no-go procedure with compound stimuli or transfer of function tests), emergent performances are not verified in pigeons after training with the go/no-go procedure with compound stimuli
24

O ensino de discriminações condicionais para idosos com comprometimento cognitivo

Souza, Fabiana Satiro de 04 November 2011 (has links)
Made available in DSpace on 2016-04-28T20:56:27Z (GMT). No. of bitstreams: 1 Fabiana Satiro de Souza.pdf: 2534530 bytes, checksum: d17c93970283e4cf5cc88f4fd3ff93a7 (MD5) Previous issue date: 2011-11-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Old age brings cognitive impairment and the memory s loss is the most frequent. So, it is necessary to implement cognitive stimulation s procedures in order to minimize or to stabilize such losses. Studies based on Behavior Analysis, particularly in equivalence relations have shown the possibility of forming new relational networks by the elderly and that relational network could help to restore repertoires that are being affected by aging, such as remembering of names of people or objects. The present research had four studies, three of them with the objective to verify if conditional relations teaching, to the participants, could help them remembering names of people or objects and the fourth study with the objective to verify if conditional discriminations teaching biographical data could form equivalence relations. The participants were four old women diagnosed with Alzheimer's disease. Before submitting them to the experimental procedures, the initial repertoire was evaluated. In the Studies 1, 2 and 3, the conditional relations were trained with sound (word dictated), image (representative of the word) and text (written word); these stimuli were presented or in simultaneous pairing or also with successive pairing (0 and 5 seconds). In the Study 4 only visual stimuli were used with simultaneous pairing. The emergence of new relations was tested, and the final repertoire was evaluated. The results of the first three studies showed improvement in remembering names behavior, but it was observed significant variation, among the participants, in the emergence of new relations. In the Study 4 was observed the emergence of equivalence relations. Some possible variables that may have interfered in the participants performance were pointed out, and suggestions for future studies were presented / Considerando-se que idosos enfrentam perdas cognitivas, sendo a mais frequente a perda de memória, torna-se necessário desenvolver atividades de estimulação cognitiva para minimizar ou estabilizar tais perdas. Na Análise do Comportamento, estudos pautados nas relações de equivalência têm mostrado a possibilidade de formação de novas redes relacionais pelo idoso, o que pode auxiliar também na reinstalação de repertórios que estão sendo afetados pelo envelhecimento, como o comportamento de lembrar nomes. O presente trabalho contou com quatro estudos, sendo que os três primeiros verificaram se o ensino de relações condicionais poderia favorecer o comportamento de lembrar nomes e o último estudo verificou se o ensino de discriminações condicionais de dados biográficos poderia favorecer a ocorrência de relações de equivalência. Participaram quatro idosas com diagnóstico de Doença de Alzheimer. Antes de submetê-las aos procedimentos experimentais, realizou-se a avaliação do repertório inicial. Nos Estudos 1, 2 e 3, o procedimento de ensino de relações condicionais utilizou estímulos nas modalidades som (palavra ditada), imagem (representativa da palavra) e texto (palavra escrita), sendo que os estímulos foram apresentados, ou apenas com pareamento simultâneo, ou também com pareamento sucessivo sem atraso e com atraso de 5 segundos. No Estudo 4, utilizaram-se apenas estímulos visuais, com pareamento simultâneo. Foi testada a emergência de novas relações, não treinadas, e se avaliou o repertório final. Os resultados dos três primeiros estudos indicaram melhora no comportamento de lembrar nomes, sendo que houve grande variação nos índices indicativos de emergência de relações não treinadas; no Estudo 4 não foi observada a emergência de relações de equivalência. Apontaram-se possíveis variáveis que podem ter interferido no desempenho das participantes, apresentando-se sugestões para futuras pesquisas
25

Relações emergentes avaliadas em testes de transferência de função em pombos / Emergent relations evaluated in transfer of function tests in pigeons

Heloisa Cursi Campos 06 December 2013 (has links)
Os resultados de Campos et al. (2011) indicaram a emergência de simetria, mas não de transitividade e equivalência em pombos com o procedimento go/no-go com estímulos compostos. O presente experimento investigou a formação de classes em testes de transferência de função após treino com o procedimento go/no-go com estímulos compostos. Quatro pombos foram treinados a responder aos estímulos compostos A1B1, A2B2, B1C1 e B2C2 e a não responder aos compostos A1B2, A2B1, B1C2 e B2C1. Posteriormente, os sujeitos foram treinados a responder em DRL 3 s a A1 e FR20 a A2. Testes de transferência de função apresentaram os estímulos de treino A1 e A2 e os estímulos de teste B1, C1, B2 e C2 para verificar se os sujeitos apresentariam taxa de respostas mais baixa a A1, B1 e C1 e mais alta a A2, B2 e C2. Os sujeitos apresentaram taxas de respostas mais baixas tanto para alguns estímulos do Conjunto 1 quanto para alguns estímulos do Conjunto 2. Portanto, os resultados dos testes de transferência de função não indicaram a formação de classes de equivalência após treino com o procedimento go/no-go com estímulos compostos em pombos. Sendo assim, independentemente dos testes empregados (testes das propriedades com o procedimento go/no-go com estímulos compostos ou teste de transferência de função), desempenhos emergentes não são verificados em pombos após treino com o procedimento go/no-go com estímulos compostos / Campos et al.s (2011) results indicated the emergence of symmetry, but not transitivity and equivalence with pigeons in a go/no-go procedure with compound stimuli. The present experiment investigated stimulus class formation in transfer of function tests after training in a go/no-go procedure with compound stimuli. Four pigeons were trained to respond to A1B1, A2B2, B1C1, and B2C2 compound stimuli e not to respond to A1B2, A2B1, B1C2, and B2C1 compounds. Subsequently, subjects were trained to respond in DRL 3 s to A1 and in FR20 to A2. Transfer of function tests presented the A1 and A2 training stimuli and the B1, C1, B2, and C2 test stimuli to verify if subjects would show a lower response rate to A1, B1, C1 and a higher response rate to A2, B2, C2. Subjects showed lower response rates to some Set-1 stimuli as well as to some Set-2 stimuli. Thus, the results of the transfer of function tests indicate that equivalence classes were not established after training with the go/no-go procedure with compound stimuli in pigeons. Therefore, regardless of the test used (tests of the properties with the go/no-go procedure with compound stimuli or transfer of function tests), emergent performances are not verified in pigeons after training with the go/no-go procedure with compound stimuli
26

Clones sous-maximaux inf-réductibles

Grecianu, Andrei-Paul January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
27

Quelques propriétés de rigidité des algèbres de von Neumann / Some Rigidity Properties of von Neumann Algebras

Marrakchi, Amine 06 June 2018 (has links)
Dans cette thèse, je m'intéresse à diverses propriétés de rigidité des algèbres de von Neumann. Dans le Chapitre 1, je démontre la solidité relative des produits croisés issus d'actions Bernoulli de type quelconque. Ce résultat repose sur la théorie de la déformation/rigidité de Popa et généralise un théorème de Chifan et Ioana en type II. Comme conséquence, dès que le groupe qui agit est non-moyennable, ces produits croisés sont premiers (n'admettent pas de décomposition non triviale en produit tensoriel de deux facteurs) et la relation d'équivalence associée est solide. Le Chapitre 2 a pour thème les facteurs pleins et les phénomènes de trous spectraux. Je montre notamment que tout facteur plein de type $III$ vérifie une propriété de trou spectral similaire à celle obtenue par Connes dans le cas II_1. Le trou spectral permet d'analyser plus finement la structure de ces facteurs et de leur groupe d'automorphismes. Je généralise ainsi un théorème de Jones en donnant une condition suffisante pour qu'un produit croisé soit plein. Cette condition est de plus nécessaire dans le cas où le groupe qui agit est abélien. Ceci permet de caractériser complètement les facteurs de type III_1 dont le cœur est plein. Dans un travail en collaboration avec C. Houdayer et P. Verraedt, nous montrons aussi qu'un produit tensoriel de deux facteurs pleins est encore plein et nous calculons ses invariants de Connes. Nous obtenons aussi un théorème d'unique décomposition McDuff qui généralise un résultat de Popa dans le cas II_1.Dans le Chapitre 3, je m'intéresse aux facteurs McDuff, i.e. qui ont la propriété d'absorber tensoriellement le facteur hyperfini, ainsi qu'à leur analogue en théorie ergodique, les relations d'équivalences stables. Je donne notamment une nouvelle caractérisation de cette propriété de stabilité qui repose sur un argument de maximalité. Cette caractérisation de type "trou spectral", plus fine que celle connue jusqu'alors, permet de démontrer le résultat de rigidité suivant: un produit direct de deux relations d'équivalences est stable si et seulement si l'une des deux est stable. Le problème similaire pour les facteurs McDuff reste ouvert, mais je donne quelques résultats partiels. / In this dissertation, I study several rigidity properties of von Neumann algebras. In Chapter 1, we prove the relative solidity of Bernoulli crossed products of arbitrary type. This result is based on Popa's deformation/rigidity and generalizes a theorem of Chifan and Ioana in the tracial case. As a consequence, when the acting group is non-amenable, the crossed product is prime (cannot be decomposed nontrivially as a tensor product of two factors) and the associated equivalence relation is solid.In Chapter 2, we study full factors in relation with the spectral gap property. The main result is a spectral gap characterization of full type III factors which is similar to Connes' characterization in the tracial case. This allows us to better understand the structure of these factors and their automorphism group. We generalize a theorem of Jones by giving a sufficient condition for a crossed product to be full. This condition is necessary when the group is abelian. In particular, we obtain a complete characterization of the type III_1 whose core is full. In a joint work with C. Houdayer and P. Verraedt, we show that a tensor product of two full factors is also full and we compute its Connes invariants. We also prove a unique McDuff decomposition theorem that generalizes a result of Popa in the II_1 case. In Chapter 3, we study McDuff factors, i.e. those factors that can absorb tensorially the hyperfinite factor, as well as their counterpart in ergodic theory, the so-called stable equivalence relations. We obtain a new "spectral gap like" characterization of these properties, based on a maximality argument. With this refined characterization, we are able to prove the following rigidity result: a direct product of two stable equivalence relations is stable if and only if one of them is already stable. The analoguous problem on McDuff factors remains open, but we do give some partial results.
28

Forcing, deskriptivní teorie množin, analýza / Forcing, deskriptivní teorie množin, analýza

Doucha, Michal January 2013 (has links)
The dissertation thesis consists of two thematic parts. The first part, i.e. chapters 2, 3 and 4, contains results concerning the topic of a new book of the supervisor and coauthors V. Kanovei and M. Sabok "Canonical Ramsey Theory on Polish Spaces". In Chapter 2, there is proved a canonization of all equivalence relations Borel reducible to equivalences definable by analytic P-ideals for the Silver ideal. Moreover, it investigates and classifies sube- quivalences of the equivalence relation E0. In Chapter 3, there is proved a canonization of all equivalence relations Borel reducible to equivalences de- finable by Fσ P-ideals for the Laver ideal and in Chapter 4, we prove the canonization for all analytic equivalence relations for the ideal derived from the Carlson-Simpson (Dual Ramsey) theorem. The second part, consisting of Chapter 5, deals with the existence of universal and ultrahomogeneous Polish metric structures. For instance, we construct a universal Polish metric space which is moreover equipped with countably many closed relations or with a Lipschitz function to an arbitrarily chosen Polish metric space. This work can be considered as an extension of the result of P. Urysohn who constructed a universal and ultrahomogeneous Polish metric space.
29

Análise das topografias de controle de estímulos envolvidas em escolhas de acordo com o modelo em indivíduos com Síndrome de Down / Analysis of topographies of stimuli control related to choice according to model in individuals with Down syndrome

Vasconcellos, Mariliz 30 June 2009 (has links)
Made available in DSpace on 2016-06-02T19:44:06Z (GMT). No. of bitstreams: 1 2963.pdf: 938446 bytes, checksum: 51bf8a04d7160d87fa142f9dc4d6c0c4 (MD5) Previous issue date: 2009-06-30 / Financiadora de Estudos e Projetos / The formation of equivalent stimuli classes is a psychological phenomenon that has important characteristics for the experimentation of processes involving symbolic behavior acquisition. This kind of behavior has been the target of a wide variety of contemporary studies which have also demonstrated the possibility of such approach to generate symbolic behavioral repertoires based only on the teaching of some relations between stimuli. It is vital to investigate the parameters that optimize the establishment of equivalent stimuli classes desired by the researcher when defining the behavior to be installed through the procedure of matching-to-sample (MTS). Studies in the area have widely shown that after training A1B1 and B1C1, there is an emergency of some relations, such as B1A1, C1B1, A1C1 and C1A1, which demonstrate, respectively, the properties of reflexivity, symmetry, transitivity and equivalence. One of the parameters that determine the effectiveness of a procedure on class formation is the type of control relation exercised by the comparison stimuli in MTS attempts. Therefore, the present study aimed to identify the role of specific types of training of conditional discriminations in the establishment of relations of control for selection and rejection. Study participants were two teenagers with Down syndrome. The training consisted on MTS sessions with and without mask in two training types: non-nodular and nodular. The former occurred by presenting stimuli which function was either model or comparison only, and the latter was characterized by presenting stimuli with dual function, i.e. model and comparison simultaneously. Verification testing of the control relations established at baseline was made after non-nodular training and after nodular training, and only then verification testing of behavioral emergency was made. Two stimuli sets involved attempts with mask, while other two consisted of attempts without a mask. The experiment was specifically designed in a way that the training of a stimuli set with mask has occurred almost simultaneously with the training of a stimuli set without mask. Thus, the influence of historical undesirable variables was avoided on deductions made from performance comparison of the two different attempts (with or without mask). Results demonstrated, generally, that the training procedure used was very effective in teaching and formation of classes, what made difficult even to compare the greater effectiveness of the procedures with or without use of mask in the training of conditional relations. It is suggested the replication of this study, with a larger number of participants of this same population, so that it is possible to evaluate the data generality. / A formação de classes de estímulos equivalentes é um fenômeno psicológico que possui características importantes para a experimentação de processos relacionados à aquisição do comportamento simbólico. Esse tipo de comportamento tem sido alvo de uma grande variedade de estudos contemporâneos que tem demonstrado, inclusive, a possibilidade desse tipo de abordagem em gerar repertórios comportamentais simbólicos com base no ensino de apenas algumas relações entre estímulos. É de fundamental importância investigar os parâmetros que aperfeiçoam o estabelecimento das classes de estímulos equivalentes desejadas pelo pesquisador, ao definirem o comportamento instalado por meio do procedimento de matching-to-sample (MTS). Estudos da área verificaram amplamente que, após o treino de A1B1 e B1C1, há emergência de algumas relações, tais como, B1A1, C1B1, A1C1 e C1A1, que demonstram, respectivamente, as propriedades de reflexividade, simetria, transitividade e equivalência. Um dos parâmetros que determinam a efetividade de um procedimento na formação de classes é o tipo de relação de controle exercido em tentativas de emparelhamento com o modelo. A partir disso, o presente estudo teve como objetivo identificar o papel de tipos específicos de treino de discriminações condicionais no estabelecimento de relações de controle por seleção e rejeição. Participaram do estudo dois jovens com síndrome de Down. O treino consistiu em sessões de MTS com e sem máscara, aonde houve treinos dos tipos não nodular, com um estímulo apresentando função única de modelo ou de comparação exclusivamente, e houve também treino do tipo nodular, caracterizado por estímulos com dupla função, ou seja, modelo e comparação simultaneamente. Os testes de verificação das relações de controle estabelecidas na linha de base foram feitos após o treino não nodular, em seguida, após o treino nodular, e só então os testes de verificação de emergência comportamental foi aplicado. Duas estruturas envolveram tentativas com máscara, enquanto as outras duas estruturas constituíram-se de tentativas sem máscara. O desenho experimental foi especificamente planejado para que, o treino de uma estrutura de treino com máscara ocorresse quase simultaneamente com o de uma estrutura sem máscara. Desse modo, evitou-se o papel de variáveis históricas indesejáveis para a inferência derivada da comparação do desempenho nos dois tipos diferentes de estruturas e tentativas. Os resultados mostraram, de um modo geral, que o procedimento de treino empregado foi bastante eficiente no ensino e formação de classes, o que dificultou, inclusive, a comparação da maior efetividade do procedimento com ou sem uso de máscara no treino das relações condicionais. Sugere-se que o estudo, embora extenso no que diz respeito ao ensino e teste de relações, considerando ainda o tipo de população envolvida, seja replicado com um número maior de participantes para que a generalidade dos dados seja avaliada.

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