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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.
131

Proposta de um procedimento para a modelagem de sistemas de controle de edifícios inteligentes utilizando a rede de Petri colorida. / A procedure for modelling the control system in intelligent buildings based on colored Petri nets.

Igei Kaneshiro, Percy Javier 22 August 2011 (has links)
Os avanços tecnológicos das últimas décadas têm motivado o desenvolvimento dos edifícios inteligentes, visando à criação de ambientes mais confortáveis e seguros para os ocupantes, economicamente vantajosos para os proprietários e ambientalmente corretos. Considerando-se que nestes ambientes emergem novas formas de interação entre os usuários e os sistemas prediais, as quais não são adequadamente tratadas por técnicas convencionais de modelagem, torna-se necessário o estudo de novas soluções que abordem essas interações. Assim, este trabalho apresenta a proposta de uma abordagem sistemática para modelar e simular os sistemas de controle de edifícios inteligentes. Considera-se o sistema de controle como um sistema orientado por eventos discretos, no qual a comunicação entre os dispositivos que o constituem é realizada por meio da troca assíncrona de mensagens. Nesta abordagem, é utilizada a rede de Petri colorida para especificar as funcionalidades do edifício inteligente e a interação entre os dispositivos que constituem o seu sistema de controle. Assim, fornece-se um procedimento estruturado para desenvolver modelos que facilita a especificação do algoritmo de controle dos subsistemas do edifício inteligente. Para avaliar as principais características do procedimento proposto, foi apresentado um exemplo de aplicação que aborda a integração das funcionalidades de um sistema de telefonia distribuído e um sistema de vigilância predial. A abordagem de modelagem possibilitou a identificação das funcionalidades dos dispositivos inteligentes que integram o sistema de controle em diferentes níveis de abstração e as interações que ocorrem durante o seu funcionamento. A realização deste trabalho contribui para o aprimoramento de novas abordagens para o desenvolvimento de sistemas de controle com arquiteturas heterárquicas. Estes sistemas são constituídos por dispositivos inteligentes colaborativos, que possuem um elevado grau de autonomia. / Technological advances in recent decades have motivated the development of intelligent buildings, aimed at creating environments more productive for the occupants, economically advantageous for the owners and environmentally correct. New ways of interaction between users and the buildings systems are emerging from these kinds of systems, which are not adequately treated by conventional modeling techniques. In this sense, it is necessary the study of new approaches which address these new functionalities. Thus, this work presents a proposal for a systematic approach to model and simulate the control system of the intelligent buildings. The control system is considered to be a discrete event system, where the communication between the devices that integrate it is oriented by means of asynchronous messages exchange. This approach uses the colored Petri nets in order to specify the functionalities of the building system and their devices interactions. The approach provides a structured procedure to develop models that facilitate the algorithm specification of the control system. In order to verify the main characteristics of the proposed procedure, it is presented an example that is a control system that integrates a distributed telephony system and a surveillance building system. The approach proposed enabled the identification of the main functionalities and interactions of the intelligent devices constituting the control system. The achievement of this thesis contributes to the development of new approaches to develop heterarchical control system architectures. This kind of system architectures is constituted by collaborative intelligent devices that have a high degree of autonomy.
132

Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida. / Policies analysis of role based access control with colored Petri net.

Ueda, Eduardo Takeo 24 May 2012 (has links)
Controle de acesso é um tópico de pesquisa importante tanto para a academia quanto para a indústria. Controle de Acesso Baseado em Papéis (CABP) foi desenvolvido no início dos anos 1990, tornando-se um padrão generalizado para controle de acesso em vários produtos e soluções computacionais. Embora modelos CABP sejam largamente aceitos e adotados, ainda existem questões para responder. Um dos principais desafios de pesquisa em segurança baseada em papéis é determinar se uma política de controle de acesso é consistente em um ambiente altamente dinâmico. Nossa pesquisa visa preencher essa lacuna fornecendo um método para analisar políticas CABP com respeito a dois aspectos significativos: segurança e dinamismo envolvendo papéis e objetos. Para este propósito, desenvolvemos um modelo de descrição e simulação de política usando rede de Petri colorida e CPN Tools. O modelo descreve e é capaz de simular vários estados CABP em um contexto de educação a distância típico. Usando este modelo, foi possível analisar o espaço de estados produzido pela rede de Petri colorida em um cenário dinâmico envolvendo a criação de novos papéis e objetos. O resultado da análise de alcançabilidade da rede de Petri da política demonstrou que é possível verificar a consistência de políticas de controle de acesso considerando a dinamicidade de papéis e objetos, e apontou vantagens de aplicabilidade da modelagem de políticas de segurança em ambientes distribuídos utilizando rede de Petri colorida. / Access control is an important research topic both for academia and industry. Role Based Access Control (RBAC) was developed in the early 1990s, becoming a generalized standard of access control for many products and computing solutions. Although RBAC models have been widely accepted and adopted, there are issues to answer. One of the key challenges for role-based security research is to characterize whether an access control policy is consistent in a highly dynamic environment. Our research aims filling this gap providing a method to analyze RBAC policies with respect to two significant aspects: security and dynamics involving roles and objects. For this purpose, we developed a policy description and simulation model using colored Petri net and the CPN Tools. The model describes and is capable to simulate many RBAC states in a typical distance education context. Using this model it was possible to analyze the state space provided by colored Petri net that simulates a dynamic environment and the creation of new roles and objects. The result of the reachability analysis of Petri net policy showed that it is possible to check the consistency of access control policies considering dynamic of roles and objects, and point out the advantages and applicability of modeling security policies in distributed environments using colored Petri net.
133

Sémantique formelle et vérification automatique de scénarios hiérarchiques multimédia avec des choix interactifs / Formal semantics and automatic verification of hierarchical multimedia scenarios with interactive choices

Arias Almeida, Jaime E. 27 November 2015 (has links)
Notre propos est la conception assistée par ordinateur des scénarios comprenant des contenus multimédia qui interagissent avec les actions extérieures, notamment celles de l’interprète (e.g., spectacles vivants, installations muséales interactives et jeux vidéo). Le contenu multimédia est structuré dans un ordre spatial et temporel selon les exigences de l’auteur. Par conséquent, la complexité potentiellement élevée de ces scénarios nécessite des langages de spécification adéquats pour leur complète description et vérification.Partitions Interactives est un formalisme qui a été proposé comme un modèle pour la composition et l’exécution des scénarios multimédias interactifs. En outre, un séquenceur inter-médias, appelé ISCORE,a été élaboré à partir de la sémantique Petri net proposée par ce formalisme. Au cours des dernières années, I-SCORE a été utilisé avec succès pour la composition et l’exécution des spectacles et des expositions interactives. Néanmoins, ces applications et les applications émergentes telles queles jeux vidéo et les installations muséales interactives, de plus en plus exigent deux caractéristiques que la version stable actuelle de I-SCORE ainsi que son modèle sous-jacent ne supportent pas : (1)des structures de contrôle flexibles comme des conditionnelles et des boucles ; et (2) des mécanismes pour la vérification automatique de scénarios.Dans cette thèse, nous présentons deux modèles formels pour la composition et la vérification automatique de scénarios interactifs multimédia avec des choix interactifs, i.e., des scénarios où l’interprète ou le système peut prendre des décisions au sujet de leur état d’exécution avec un certain degré de liberté définie par le compositeur.Dans notre première approche, nous définissons un nouveau langage de programmation appelé REACTIVEIS dont les programmes sont définis comme des arbres représentant l’aspect hiérarchique des scénarios interactifs et dont les noeuds contiennent les conditions nécessaires pour démarrer et arrêter les objets temporels (TOS). En outre, nous définissons une sémantique opérationnelle basé sur des arbres marqués, contenant dans leurs noeuds, les informations sur le début et la fin de chaque TO. Nous définissons également une interprétation déclarative de REACTIVEIS comme formules de la logique linéaire intuitionniste avec sous exponentiels (SELL). Nous montrons que cette interprétation est adéquate : les dérivations dans la logique correspondent à des traces du programme et vice-versa.Dans notre deuxième approche, nous présentons un système basé sur des Automates Temporisés.Dans le système proposé, nous modélisons des scénarios interactifs comme un réseau d’automates temporisés et les étendons avec des points interactifs gardés par des conditions, permettant ainsi la spécification de comportements avec branchements. Par ailleurs, nous profitons des outils matures et efficaces pour simuler et vérifier automatiquement des scénarios modélisés comme des automates temporisés. Dans notre système, les scénarios peuvent être synthétisés dans un matériel reconfigurable afin de fournir une faible latence et l’exécution en temps réel.Dans cette thèse, nous explorons également une nouvelle façon de définir et mettre en oeuvre des scénarios interactifs, visant à un modèle plus dynamique en utilisant le langage réactif REACTIVEML.Enfin, nous présentons une extension des scénarios interactifs utilisant des réseaux de Petri colorés(CPN) qui vise à traiter des données complexes, en particulier, les données statiques et dynamiques de flux audio. / Interactive multimedia deals with the computer-based design of scenarios consisting of multimediacontent that interacts with external actions and those of the performer (e.g., multimedialive-performance arts, interactive museum installations, and video games). The multimedia content is structured in a spatial and temporal order according to the author’s requirements. Therefore, thepotentially high complexity of these scenarios requires adequate specification languages for theircomplete description and verification.Interactive scores is a formalism which has been proposed as a model for composing and performing interactive multimedia scenarios. In addition, an inter-media sequencer, called I-SCORE, hasbeen developed following the Petri Net semantics proposed by this formalism. During the last years,I-SCORE has been used successfully for the composition and performance of live performances and interactive exhibitions. Nevertheless, these applications and emergent applications such as videogames and interactive museum installations, increasingly demand two features that the current stable version of I-SCORE as well as its underlying model do not support: (1) flexible control structures such as conditionals and loops; and (2) mechanisms for the automatic verification of scenarios.In this dissertation we present two formal models for composition and automatic verification of multimedia interactive scenarios with interactive choices, i.e., scenarios where the performer or thesystem can take decisions about their execution state with a certain degree of freedom defined bythe composer.In our first approach, we define a novel programming language called REACTIVEIS. This language extends the full capacity of temporal organization of interactive scenarios by allowing the composerto use a defined logical system for the specification of the starting and stopping conditions of temporal objects (TOs). REACTIVEIS programs are formally defined as tree-like structures representing the hierarchical aspect of interactive scenarios and whose nodes contain the conditions needed to startand stop the TOs. Moreover, we define an operational semantics based on labeled trees, containing in their nodes, the information about the start and stop times of each TO.We show that this operational semantics offers an intuitive yet precise description of the behavior of interactive scenarios.We also endowed REACTIVEIS with a declarative interpretation as formulas in Intuitionistic LinearLogic with Subexponentials (SELL). We shall show that such interpretation is adequate: derivations in the logic correspond to traces of the program and vice-versa. Hence, we can use all the meta-theory of Intuitionistic Linear Logic (ILL) to reason about interactive scenarios and develop tools for theverification and analysis of interactive scenarios.In our second approach, we present a Timed Automata (TA) based framework. In the proposed framework, we model interactive scenarios as a network of timed automata and extend them with interactive points (IPs) guarded by conditions, thus allowing for the specification of branching behaviors.Moreover, we take advantage of the mature and efficient tools for TA to simulate and automatically verify scenarios. In our framework, scenarios can be synthesized into a reconfigurable hardware in order to provide a low-latency and real-time execution by taking advantage of the physical parallelism,low-latency, and high-reliability of these devices. Furthermore, we implemented a tool to systematically construct bottom-up TA models from the composition environment of I-SCORE. Doing that, we provide a friendly and specialized environment for composing and automatic verification of interactive scenarios. Finally, we present an extension of interactive scenarios using Colored Petri Nets (CPNs) thataims to handle complex data, in particular, dynamic and static data audio streams. [...]
134

Les Libres de couleur face au préjugé : franchir la barrière à la Martinique aux XVIIe-XVIIIe siècles / Free colored people confronted with prejudice : crossing lines in Martinique in the seventeenth and eighteenth centuries

Pierre-Louis, Jessica 20 June 2015 (has links)
À la Martinique au XVIIIe siècle, les « libres de couleur », qu’ils soient nés libres ou affranchis, noirs ou métis, forment une catégorie juridique distincte des Blancs et des esclaves. L’étude comparée, avec les territoires espagnols ou anglais, montre qu’aucune réglementation légale n’a officialisé un passage de la catégorie Libre de couleur à celle de Blanc dans les colonies françaises de la fin du XVIIe siècle à la Révolution française. Aussi, cette thèse se propose de montrer les processus officieux qui ont permis à certaines personnes – les « assimilés » – de franchir la barrière de couleur. Une réflexion a été menée sur le préjugé de couleur, système raciste dont l’idéologie, soutenue par la réglementation locale, a légitimé la construction collective d’un ordre public et social. Puis, on a examiné l’élaboration de la barrière de couleur. Les libres de couleur ont été les premiers à faire les frais de l’imperméabilisation de la ligne de démarcation et des problèmes posés par la pureté de sang ; mais les Blancs mésalliés, dans le cadre d’unions interraciales, et les Amérindiens ont aussi été visés. Enfin nous avons réfléchi à ce qui faisait la blancheur et aux stratégies adoptées pour réussir ce changement de statut. Le notariat et les 33 000 actes des registres paroissiaux traités ont donné lieu à la reconstitution de généalogies pour examiner des individus et des familles sur plusieurs générations ; on a ainsi observé l’importance du phénotype, le blanchiment, la légitimité des relations, les conjoints privilégiés, le choix des réseaux, les niveaux de fortune et l’usage de l’espace. / In Martinique in the eighteenth century, the "free people of color", both those free by birth and freedmen, black or mixed race, form a legal category, which was distinct from those of whites and slaves. Comparative studies with Spanish or English territories show that no legal regulation formalized a shift - from the category of free colored people to that of White - in the French colonies between the late seventeenth century and the French Revolution. Also, this thesis proposes to show the informal process that enabled some people - the "assimilated" - to cross the color barrier. I analysed the color prejudice, a racist system, whose ideology, supported by local regulations, legitimized the collective construction of a public and social order. In a second step, I examined the development of the color bar. The free colored people were the first to bear the brunt of the impermeability of the demarcation line and of the problems posed by the purity of blood; but some whites, through interracial unions, and Native Americans have also been targeted. Finally I thought about what made the whiteness, and the strategies to achieve whiteness, change in status. Notarial acts and 33,000 acts of parish registers treaties led to the reconstitution of genealogies, in order to examine individuals and families over generations; I observed the importance of the phenotype, whitening, legitimacy relations, privileged partners, choice of networks, wealth levels and the use of space.
135

Relations entre les propriétés optiques de la matière organique dissoute colorée et le carbone organique dissous dans des eaux côtières aux caractéristiques contrastées / Relationships between colored dissolved organic matter optical properties and dissolved organic carbon in contrasted coastal waters

Danhiez, François-Pierre 18 December 2015 (has links)
A l'heure actuelle le rôle des zones côtières dans le cycle global du carbone est encore relativement mal documenté. Ceci est lié à la forte hétérogénéité et au fort dynamisme de ces zones au sein desquelles de nombreux processus physiques et biologiques interagissent sur les stocks et les flux de carbone. Le carbone organique dissous (DOC) est un élément essentiel à la compréhension du cycle du carbone océanique, notamment dans les zones côtières où il peut représenter jusqu'à 90% du carbone organique total. Compte tenu des nombreuses incertitudes qui résident encore sur la dynamique de cette matière carbonée, l'objectif général de cette thèse visait à améliorer les connaissances sur la distribution du DOC au niveau de ces interfaces "continent/océan" en s'appuyant sur les propriétés optiques de la fraction colorée de ce DOC, la matière organique dissoute (CDOM). Pour cela, des échantillonnages ont été réalisés entre 2010 et 2015 dans trois sites côtiers fortement contrastés (Manche orientale, Guyane Française, Vietnam) et ont permis de : (i) caractériser la dynamique de la CDOM et du DOC et d'identifier une forte hétérogénéité de la relation entre ces deux paramètres au sein de ces sites côtiers aux caractéristiques contrastés, (ii) de proposer une relation novatrice applicable à la télédétection "couleur de l'eau" permettant de dériver les concentrations en DOC à partir des propriétés optiques de la CDOM potentiellement généralisable dans des sites côtiers dominés par les apports terrigènes. Dans un second temps, des études en milieu contrôle (45 jours) couplées à un suivi de terrain (2012-2014) ont été effectuées afin de caractériser spécifiquement la cinétique et l'impact d'une production biologique de matière organique dissoute sur les relations entre CDOM et DOC. Elles ont permis d'identifier un marquage optique (i.e. S320-412) de cette production autochtone de MOD lors de l'efflorescence printanière de Phaeocystis.globosa caractéristique des eaux côtières de la Manche et de proposer une approche pour estimer les contenus en DOC depuis les propriétés optiques du CDOM dans de telles situations de production marine de matière organique dissoute. / The coastal ocean represents an important component of the global carbon cycle however its participation to the overall carbon flux is currently not well constrained. Information on DOC stock and its variability in the coastel ocean is however still very scarce and its represents a strong limitation to our current understanding of the exact role of these ecosystems in the oceanic carbon cycle. In this context, the general aims of this study was to get more insights on dissolved organic carbon dynamics in the coastal ocean through the optical properties of dissolved organic matter (CDOM) that present the advantage to be easily measured from in situ or satellite observations. In practice, in situ data gathered during several sampling cruises conducted in three constrasted continental margins (Eastern Channel, French Guiana, Vietnam) have allowed : (i) the characterization of the strong regional discrepancies in the CDOM-DOC relationships between the three coastal sites investigated, (ii) the possible use of a generalized parameterization to retrieve DOC concentrations from CDOM optical properties (estimated in situ or from ocean color remote sensing)over a large range of coastal sites dominated by terrestrial imput of DOM. A further objective of this work was to investigate the impact on DOM dynamics of the phytoplankton bloom event of Phaeocystis.globosa known to affect the coastal waters of the eastern English Channel during the spring period. In practice, this DOM production was investigated during a 45 days mesocom experiment coupled to field survey data (2012-1014) leading to the identification of an optical marker of this marine CDOM production (i.e. S320-412). We further demonstrated that this optical parameter provides useful information to enhance our ability to retrieve DIC 1 from CDOM optical properties in a context of an algal bloom event.
136

DiagnÃstico de Faltas em Sistemas ElÃtricos baseado em Redes de Petri Coloridas e TÃcnicas de Sistemas Especialistas / Fault Diagnosis on Electric Systems, Based on Colored Petri Nets and Expert Systems Techniques

Francisco Gualberto Santos Filho 30 July 2007 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Quando o sistema elÃtrico experimenta qualquer distÃrbio uma avalanche de alarmes à reportada ao Centro de OperaÃÃo do Sistema (COS) dificultando ao operador na identificaÃÃo da causa do distÃrbio. O grande volume de informaÃÃes disponibilizado pelos sistemas supervisÃrios em condiÃÃo de falta no sistema elÃtrico à de pouco valor se nÃo possibilitar um rÃpido diagnÃstico, para uma pronta e correta tomada de decisÃo e restabelecimento à condiÃÃo normal de operaÃÃo. Usando como entrada os dados informados pelo SCADA foi desenvolvido um Sistema de DiagnÃstico de Faltas (SDF), baseado em Redes de Petri Coloridas (RPC), que filtra as informaÃÃes do SCADA e à capaz de fornecer em tempo real aos operadores o diagnÃstico para as faltas no sistema. O diagnÃstico à obtido a partir da simulaÃÃo off-line de um expressivo nÃmero de possÃveis faltas no sistema em que a marcaÃÃo final da RPC para cada falta à convertida em diagnÃstico. Um Programa Especialista foi desenvolvido para a interpretaÃÃo da marcaÃÃo final fornecida pela RPC para geraÃÃo automÃtica do diagnÃstico de falta. O Programa Especialista interpreta os resultados do modelo RPC independente do sistema elÃtrico monitorado, diagnosticando os eventos que ocorrem tanto em uma subestaÃÃo quanto nas linhas de transmissÃo que ligam as subestaÃÃes, fornecendo um diagnÃstico rÃpido, sucinto, e com formato e linguagem comuns ao operador. / When a fault occurs in an electrical system often an avalanche of information is made available to the System Operation Center making it difficult to the operator to identify the cause of the fault. The great deal of information provided by the supervisory system is of any value if it does not make easy to the operator, to take a right and prompt decision to bring the system back to normal operation. Based on the SCADA information a Fault Diagnosis System (SDF) was developed, which uses the Colored Petri Nets (CPN) method to filter out the large amount of information made available by the SCADA system and then to give the fault diagnosis. The drawback of the SDF is that the fault diagnosis is developed off line from the CPN final markings for all the likely fault conditions on the power system. In this work an Expert Program is developed to automatically convert the CPN final markings into the system fault diagnosis. The Expert Program interprets the results of the CPN model independent of the monitored electrical system, it diagnosis events that occur in substations as much as the transmission lines that connect the substations, providing a fast and concise diagnosis with common format and language to the operator.
137

Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida. / Policies analysis of role based access control with colored Petri net.

Eduardo Takeo Ueda 24 May 2012 (has links)
Controle de acesso é um tópico de pesquisa importante tanto para a academia quanto para a indústria. Controle de Acesso Baseado em Papéis (CABP) foi desenvolvido no início dos anos 1990, tornando-se um padrão generalizado para controle de acesso em vários produtos e soluções computacionais. Embora modelos CABP sejam largamente aceitos e adotados, ainda existem questões para responder. Um dos principais desafios de pesquisa em segurança baseada em papéis é determinar se uma política de controle de acesso é consistente em um ambiente altamente dinâmico. Nossa pesquisa visa preencher essa lacuna fornecendo um método para analisar políticas CABP com respeito a dois aspectos significativos: segurança e dinamismo envolvendo papéis e objetos. Para este propósito, desenvolvemos um modelo de descrição e simulação de política usando rede de Petri colorida e CPN Tools. O modelo descreve e é capaz de simular vários estados CABP em um contexto de educação a distância típico. Usando este modelo, foi possível analisar o espaço de estados produzido pela rede de Petri colorida em um cenário dinâmico envolvendo a criação de novos papéis e objetos. O resultado da análise de alcançabilidade da rede de Petri da política demonstrou que é possível verificar a consistência de políticas de controle de acesso considerando a dinamicidade de papéis e objetos, e apontou vantagens de aplicabilidade da modelagem de políticas de segurança em ambientes distribuídos utilizando rede de Petri colorida. / Access control is an important research topic both for academia and industry. Role Based Access Control (RBAC) was developed in the early 1990s, becoming a generalized standard of access control for many products and computing solutions. Although RBAC models have been widely accepted and adopted, there are issues to answer. One of the key challenges for role-based security research is to characterize whether an access control policy is consistent in a highly dynamic environment. Our research aims filling this gap providing a method to analyze RBAC policies with respect to two significant aspects: security and dynamics involving roles and objects. For this purpose, we developed a policy description and simulation model using colored Petri net and the CPN Tools. The model describes and is capable to simulate many RBAC states in a typical distance education context. Using this model it was possible to analyze the state space provided by colored Petri net that simulates a dynamic environment and the creation of new roles and objects. The result of the reachability analysis of Petri net policy showed that it is possible to check the consistency of access control policies considering dynamic of roles and objects, and point out the advantages and applicability of modeling security policies in distributed environments using colored Petri net.
138

Proposta de um procedimento para a modelagem de sistemas de controle de edifícios inteligentes utilizando a rede de Petri colorida. / A procedure for modelling the control system in intelligent buildings based on colored Petri nets.

Percy Javier Igei Kaneshiro 22 August 2011 (has links)
Os avanços tecnológicos das últimas décadas têm motivado o desenvolvimento dos edifícios inteligentes, visando à criação de ambientes mais confortáveis e seguros para os ocupantes, economicamente vantajosos para os proprietários e ambientalmente corretos. Considerando-se que nestes ambientes emergem novas formas de interação entre os usuários e os sistemas prediais, as quais não são adequadamente tratadas por técnicas convencionais de modelagem, torna-se necessário o estudo de novas soluções que abordem essas interações. Assim, este trabalho apresenta a proposta de uma abordagem sistemática para modelar e simular os sistemas de controle de edifícios inteligentes. Considera-se o sistema de controle como um sistema orientado por eventos discretos, no qual a comunicação entre os dispositivos que o constituem é realizada por meio da troca assíncrona de mensagens. Nesta abordagem, é utilizada a rede de Petri colorida para especificar as funcionalidades do edifício inteligente e a interação entre os dispositivos que constituem o seu sistema de controle. Assim, fornece-se um procedimento estruturado para desenvolver modelos que facilita a especificação do algoritmo de controle dos subsistemas do edifício inteligente. Para avaliar as principais características do procedimento proposto, foi apresentado um exemplo de aplicação que aborda a integração das funcionalidades de um sistema de telefonia distribuído e um sistema de vigilância predial. A abordagem de modelagem possibilitou a identificação das funcionalidades dos dispositivos inteligentes que integram o sistema de controle em diferentes níveis de abstração e as interações que ocorrem durante o seu funcionamento. A realização deste trabalho contribui para o aprimoramento de novas abordagens para o desenvolvimento de sistemas de controle com arquiteturas heterárquicas. Estes sistemas são constituídos por dispositivos inteligentes colaborativos, que possuem um elevado grau de autonomia. / Technological advances in recent decades have motivated the development of intelligent buildings, aimed at creating environments more productive for the occupants, economically advantageous for the owners and environmentally correct. New ways of interaction between users and the buildings systems are emerging from these kinds of systems, which are not adequately treated by conventional modeling techniques. In this sense, it is necessary the study of new approaches which address these new functionalities. Thus, this work presents a proposal for a systematic approach to model and simulate the control system of the intelligent buildings. The control system is considered to be a discrete event system, where the communication between the devices that integrate it is oriented by means of asynchronous messages exchange. This approach uses the colored Petri nets in order to specify the functionalities of the building system and their devices interactions. The approach provides a structured procedure to develop models that facilitate the algorithm specification of the control system. In order to verify the main characteristics of the proposed procedure, it is presented an example that is a control system that integrates a distributed telephony system and a surveillance building system. The approach proposed enabled the identification of the main functionalities and interactions of the intelligent devices constituting the control system. The achievement of this thesis contributes to the development of new approaches to develop heterarchical control system architectures. This kind of system architectures is constituted by collaborative intelligent devices that have a high degree of autonomy.
139

Avaliação de pilares de concreto armado colorido de alta resistência, submetidos a elevadas temperaturas. / Evaluation of reinforced HSCC columns at high temperature.

Britez, Carlos Amado 23 March 2011 (has links)
Apesar da quantidade de variáveis envolvidas, ainda persiste uma dúvida na comunidade acadêmica sobre o comportamento do concreto de alta resistência em situação de incêndio, considerando-o como mais ou menos suscetível à ocorrência do fenômeno de desplacamento (spalling) tipo explosivo. Em parte, essa dúvida decorre do fato de que, muitas vezes, os programas experimentais são conduzidos em amostras envolvendo corpos-de-prova padronizados, cilíndricos ou cúbicos, que não levam em consideração a influência de parâmetros relacionados com as dimensões dos elementos estruturais nem com a taxa e configuração das armaduras. Outros aspectos relevantes, como o tipo de agregado utilizado na mistura de concreto, bem como a idade e umidade interna do elemento ensaiado, dificilmente são abordados nas pesquisas e, muitas vezes, simplesmente são omitidos, o que dificulta a visão ampla e real do comportamento térmico do concreto de alta resistência. Esta pesquisa apresenta um programa experimental pioneiro realizado no Brasil em um pilar de concreto de alta resistência, armado, colorido, com idade de oito anos, fc,8anos de 140MPa, agregado graúdo basáltico, agregado miúdo quartzoso, seção transversal de 70cm x 70cm, 200cm de altura, ensaiado sem carregamento e com exposição de três faces pelo período de 180 minutos (3h), sob as temperaturas da curva-padrão de incêndio ISO 834. O pilar protótipo ensaiado é réplica dos pilares reais do edifício e-Tower, construído em 2002, na cidade de São Paulo, Brasil. Os resultados obtidos demonstraram que, neste caso, o concreto colorido de alta resistência comportou-se de forma íntegra frente ao fogo e que a utilização de pigmento à base de óxido de ferro, pode atuar também como um excelente termômetro natural, auxiliando na avaliação da condição da estrutura pósincêndio. / In spite of the several factors that influence the behavior of concrete columns under fire conditions, there is a belief among the research community, that the high-strength concrete is more susceptible to explosive spalling than normal-strength concrete. This doubt, in part, is attributed to the small unreinforced concrete samples (specimens) used in experimental programs, to evaluate the fire resistance of structural concrete. On the other hand, relevant aspects as the coarse aggregate type used in the concrete mixture, as well as the age and content moisture (relative humidity) are not considered in the researches and sometimes simply omitted. This research presents a pioneer experimental program, carried out in Brazil on a high strength colored reinforced concrete column (HSCC) with 200cm high, eight yearsold, fc,8years of 140MPa, basalt coarse aggregate, cross section of 700mm x 700mm, tested under no load and with three faces exposed to a standard fire curve ISO 834 for a period of 180min (3h). The column prototype is a replica of the actual columns of the e-Tower Building, constructed in 2002 in São Paulo city, Brazil. The results demonstrated concrete column integrity under experimental fire and that the iron oxide pigments can work as an excellent natural thermometer, contributing in the evaluation of the structure post-fire.
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Some People Call Them Dolls: Capturing the Iconic Power of the Female Form in Non-ferrous Metals.

Pack, Alison Greer 01 May 2003 (has links)
The artist discusses her Master of Fine Arts exhibition at East Tennessee State University, Slocumb Galleries, Johnson City, Tennessee, October 28-November 8, 2002. Her exhibition was a personal narrative of her southern upbringing in small town Appalachia as well as a reflection of her inner thoughts and feelings towards feminism, adolescence, sexuality and Barbie. She chose to reference the female form, void of an actual body, implied through clothing. Works are figurative and sculptural and are constructed of copper, sterling and fine silver. They are sculptural hollow vessels, raised, formed, and colored with gesso and prismacolor pencils. Topics discussed: the artist's experiences as a woman, development in graduate school, casting versus raising, a detailed technical discussion on each piece, the influences of Marilyn da Silva’s use of the narrative and color on metal, and Judith Shea’s use of clothing to reference the human form. Includes images and discussions of twenty-six works and images of the exhibition.

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