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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.
31

Reasoning Tradeoffs in Implicit Invocation and Aspect Oriented Languages

Sanchez Salazar, Jose 01 January 2015 (has links)
To reason about a program means to state or conclude, by logical means, some properties the program exhibits; like its correctness according to certain expected behavior. The continuous need for more ambitious, more complex, and more dependable software systems demands for better mechanisms to modularize them and reason about their correctness. The reasoning process is affected by the design decisions made by the developer of the program and by the features supported by the programming language used. Beyond Object Orientation, Implicit Invocation and Aspect Oriented languages pose very hard reasoning challenges. Important tradeoffs must be considered while reasoning about a program: modular vs. non-modular reasoning, case-by-case analysis vs. abstraction, explicitness vs. implicitness; are some of them. By deciding a series of tradeoffs one can configure a reasoning scenario. For example if one decides for modular reasoning and explicit invocation a well-known object oriented reasoning scenario can be used. This dissertation identifies various important tradeoffs faced when reasoning about implicit invocation and aspect oriented programs, characterize scenarios derived from making choices regarding these tradeoffs, and provides sound proof rules for verification of programs covered by all these scenarios. Guidance for program developers and language designers is also given, so that reasoning about these types of programs becomes more tractable.
32

Verificação de Projetos de Sistemas Embarcados através de Cossimulação Hardware/Software

Silva Junior, José Cláudio Vieira e 17 August 2015 (has links)
Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2016-02-16T14:54:49Z No. of bitstreams: 1 arquivovotal.pdf: 4473573 bytes, checksum: 152c2f0d263c50dcbea7d500d5f7f5da (MD5) / Made available in DSpace on 2016-02-16T14:54:49Z (GMT). No. of bitstreams: 1 arquivovotal.pdf: 4473573 bytes, checksum: 152c2f0d263c50dcbea7d500d5f7f5da (MD5) Previous issue date: 2015-08-17 / Este trabalho propõe um ambiente para verificação de sistemas embarcados heterogêneos através da cossimulação distribuída. A verificação ocorre de maneira síncrona entre o software do sistema e o sistema embarcado usando a High Level Architecture (HLA) como middeware. A novidade desta abordagem não é apenas fornecer suporte para simulações, mas também permitir a integração sincronizada com todos os dispositivos de hardware físico. Neste trabalho foi utilizado o Ptolemy como uma plataforma de simulação. A integração do HLA com Ptolemy e os modelos de hardware abre um vasto conjunto de aplicações, como o de teste de vários dispositivos ao mesmo tempo, executando os mesmos, ou diferentes aplicativos ou módulos, a execução de multiplos dispositivos embarcados para a melhoria de performance. Além disso a abordagem de utilização do HLA, permite que sejam interligados ao ambiente, qualquer tipo de robô, assim como qualquer outro simulador diferente do Ptolemy. Estudo de casos são apresentado para provar o conceito, mostrando a integração bem sucedida entre o Ptolemy e o HLA e a verificação de sistemas utilizando Hardware-in-the-loop e Robot-in-the-loop. / This work proposes an environment for verification of heterogeneous embedded systems through distributed co-simulation. The verification occurs in real-time co-simulating the system software and hardware platform using the High Level Architecture (HLA) as a middleware. The novelty of this approach is not only providing support for simulations, but also allowing the synchronous integration with any physical hardware devices. In this work we use the Ptolemy framework as a simulation platform. The integration of HLA with Ptolemy and the hardware models open a vast set of applications, like the test of many devices at the same time, running the same, or different applications or modules, the usage of Ptolemy for real-time control of embedded systems and the distributed execution of different embedded devices for performance improvement. Furthermore the use of HLA approach allows them to be connected to the environment, any type of robot, as well as any other Ptolemy simulations. Case studies are presented to prove the concept, showing the successful integration between Ptolemy and the HLA and verification systems using Hardware-in-the-loop and Robot-in-the-loop.
33

Desenvolvimento e Avaliação de Simulação Distribuída para Projeto de Sistemas Embarcados com Ptolemy

Negreiros, ângelo Lemos Vidal de 29 January 2014 (has links)
Made available in DSpace on 2015-05-14T12:36:43Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3740448 bytes, checksum: df44ddc74f1029976a1e1beb1c698bf6 (MD5) Previous issue date: 2014-01-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nowadays, embedded systems have a huge amount of computational power and consequently, high complexity. It is quite usual to find different applications being executed in embedded systems. Embedded system design demands for method and tools that allow the simulation and verification in an efficient and practical way. This paper proposes the development and evaluation of a solution for embedded modeling and simulation of heterogeneous Models of Computation in a distributed way by the integration of Ptolemy II and the High Level Architecture (HLA), a middleware for distributed discrete event simulation, in order to create an environment with high-performance execution of large-scale heterogeneous models. Experimental results demonstrated that the use of a non distributed simulation for some situations as well as the use of distributed simulation with few machines, like one, two or three computers can be infeasible. It was also demonstrated the feasibility of the integration of both technologies and so the advantages in its usage in many different scenarios. This conclusion was possible because the experiments captured some data during the simulation: execution time, exchanged data and CPU usage. One of the experiments demonstrated that a speedup of factor 4 was acquired when a model with 4,000 thousands actors were distributed in 8 different machines inside an experiment that used up to 16 machines. Furthermore, experiments have also shown that the use of HLA presents great advantages in fact, although with certain limitations. / Atualmente, sistemas embarcados têm apresentado grande poder computacional e consequentemente, alta complexidade. É comum encontrar diferentes aplicações sendo executadas em sistemas embarcados. O projeto de sistemas embarcados demanda métodos e ferramentas que possibilitem a simulação e a verificação de um modo eficiente e prático. Este trabalho propõe o desenvolvimento e a avaliação de uma solução para a modelagem e simulação de sistemas embarcados heterogêneos de forma distribuída, através da integração do Ptolemy II com o High Level Architecture (HLA), em que o último é um middleware para simulação de eventos discretos distribuídos. O intuito dessa solução é criar um ambiente com alto desempenho que possibilite a execução em larga escala de modelos heterogêneos. Os resultados dos experimentos demonstraram que o uso da simulação não distribuída para algumas situações assim como o uso da simulação distribuída utilizando poucas máquinas, como, uma, duas ou três podem ser inviável. Demonstrou-se também a viabilidade da integração das duas tecnologias, além de vantagens no seu uso em diversos cenários de simulação, através da realização de diversos experimentos que capturavam dados como: tempo de execução, dados trocados na rede e uso da CPU. Em um dos experimentos realizados consegue-se obter o speedup de fator quatro quando o modelo com quatro mil atores foi distribuído em oito diferentes computadores, em um experimento que utilizava até 16 máquinas distintas. Além disso, os experimentos também demonstraram que o uso do HLA apresenta grandes vantagens, de fato, porém com certas limitações.
34

Formal and incremental verification of SysML for the design of component-based system / Vérification formelle et incrémentale de spécifications SysML pour la conception de systèmes à base de composants

Carrillo Rozo, Oscar 17 December 2015 (has links)
Vérification Formelle et Incrémentale de Spécifications SysML pour la Conception de Systèmes à Base de ComposantsLe travail présenté dans cette thèse est une contribution à la spécification et la vérification des Systèmes à Base de Composants (SBC) modélisé avec le langage SysML. Les SBC sont largement utilisés dans le domaine industrielet ils sont construits en assemblant différents composants réutilisables, permettant ainsi le développement de systèmes complexes en réduisant leur coût de développement. Malgré le succès de l'utilisation des SBC, leur conception est une étape de plus en plus complexe qui nécessite la mise en {\oe}uvre d'approches plus rigoureuses.Pour faciliter la communication entre les différentes parties impliquées dans le développement d'un SBC, un des langages largement utilisé est SysML, qui permet de modéliser, en plus de la structure et le comportement du système, aussi ses exigences. Il offre un standard de modélisation, spécification et documentation de systèmes, dans lequel il est possible de développer un système, partant d'un niveau abstrait, vers des niveaux plus détaillés pouvant aboutir à une implémentation. %Généralement ces systèmes sont faits plus grands parce qu'ils sont développés avec des cadres logiciels.Dans ce contexte nous avons traité principalement deux problématiques.La première est liée au développement par raffinement d'un SBC modélisé uniquement par ses interfaces SysML. Notre contribution permet au concepteur des SBC de garantir formellement qu'une composition d'un ensemble de composants élémentaires et réutilisables raffine une spécification abstraite d'un SBC. Dans cette contribution, nous exploitons les outils: Ptolemy pour la vérification de la compatibilité des composants assemblés, et l'outil MIO Workbench pour la vérification du raffinementLa deuxième problématique traitée concerne la difficulté de déterminer quoi construire et comment le construire, en considérant seulement les exigences du système et des composants réutilisables, donc la question qui en découle est la suivante: comment spécifier une architecture SBC qui satisfait toutes les exigences du système? Nous proposons une approche de vérification formelle incrémentale basée sur des modèles SysML et des automates d'interface pour guider, par les exigences, le concepteur SBC afin de définir une architecture de système cohérente, qui satisfait toutes les exigences SysML proposées. Dans cette approche nous exploitons le model-checker SPIN et la LTL pour spécifier et vérifier les exigences.Mots clés: {Modélisation, Spécifications SysML, Architecture SBC, Raffinement, Compatibilité, Exigences, Propriétés LTL, Promela/SPIN, Ptolemy, MIO Workbench} / Formal and Incremental Verification of SysML Specifications for the Design of Component-Based SystemsThe work presented in this thesis is a contribution to the specification and verification of Component-Based Systems (CBS) modeled in SysML. CBS are widely used on the industrial field, and they are built by assembling various reusable components, allowing developing complex systems at lower cost.Despite the success of the use of CBS, their design is an increasingly complex step that requires the implementation of more rigorous approaches.To ease the communication between the various stakeholders in a CBS development project, one of the widely used modeling languages is SysML, which besides allowing modeling of structure and behavior, it has capabilities to model requirements. It offers a standard for modeling, specifying and documenting systems, wherein it is possible to develop a system, starting from an abstract level, to more detailed levels that may lead to an implementation.In this context, we have dealt mainly two issues. The first one concerns the development by refinement of a CBS, which is described only by its SysML interfaces and behavior protocols. Our contribution allows the designer of CBS to formally ensure that a composition of a set of elementary and reusable components refines an abstract specification of a CBS. In this contribution, we use the tools: Ptolemy for the verification of compatibility of the assembled components and MIO Workbench for refinement verification.The second one concerns the difficulty to decide what to build and how to build it, considering only system requirements and reusable components. Therefore, the question that arises is: how to specify a CBS architecture, which satisfies all system requirements? We propose a formal and incremental verification approach based on SysML models and interface automata to guide, by the requirements, the CBS designer to define a coherent system architecture that satisfies all proposed SysML requirements. In this approach we use the SPIN model-checker and LTL properties to specify and verify requirements.Keywords: {Modeling, SysML specifications, CBS architecture, Refinement, Compatibility, Requirements, LTL properties, Promela/SPIN, Ptolemy, MIO Workbench}
35

Algoritmy souběžného technického a programového návrhu / Hardware-Software Codesign Algorithms

Vlach, Jan January 2007 (has links)
This master's thesis deals with a parallel design of the program and a technical equipment of embedded systems. It involves both a general description of the whole process and an illustration of the design, a simulation and implementation of the FIR filter. It also includes a description of the proposed program Polis and the simulation system Ptolemy. The conclusion of the project is devoted to a generation of simulation models in VHDL language incl. a subsequent synthesis.
36

Pythagoras at the smithy : science and rhetoric from antiquity to the early modern period

Tang, Andy chi-chung 07 November 2014 (has links)
It has been said that Pythagoras discovered the perfect musical intervals by chance when he heard sounds of hammers striking an anvil at a nearby smithy. The sounds corresponded to the same intervals Pythagoras had been studying. He experimented with various instruments and apparatus to confirm what he heard. Math, and in particular, numbers are connected to music, he concluded. The discovery of musical intervals and the icon of the musical blacksmith have been familiar tropes in history, referenced in literary, musical, and visual arts. Countless authors since Antiquity have written about the story of the discovery, most often found in theoretical texts about music. However, modern scholarship has judged the narrative as a myth and a fabrication. Its refutation of the story is peculiar because modern scholarship has failed to disprove the nature of Pythagoras’s discovery with valid physical explanations. This report examines the structural elements of the story and traces its evolution since Antiquity to the early modern period to explain how an author interprets the narrative and why modern scholarship has deemed it a legend. The case studies of Nicomachus of Gerasa, Claudius Ptolemy, Boethius, and Marin Mersenne reveal not only how the story about Pythagoras’s discovery functions for each author, but also how the alterations in each version uncover an author’s views on music. / text
37

Modelagem e simulação do deslocamento de pessoas para estimativa de formação de grupos

Véras, Frank César Lopes 25 February 2013 (has links)
Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2016-02-05T15:54:58Z No. of bitstreams: 1 arquivototal.pdf: 4833402 bytes, checksum: 88ffcf3db8082fc50d986d744b72fd34 (MD5) / Made available in DSpace on 2016-02-05T15:54:58Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 4833402 bytes, checksum: 88ffcf3db8082fc50d986d744b72fd34 (MD5) Previous issue date: 2013-02-25 / The use of Wireless Sensor Networks (WSN) has been widespread in many areas of research and application. The purpose of this work is a study on how to use sensors to monitor people on the move, having a WSN as a way in which the search will occur, but in order to predict the formation of groups in certain regions. For this work the network was designed and tested in the simulator Ptolemy II, using the ZigBee Communication protocol, where the sensors were positioned according to a Cartesian coordinate system. The WSN will detect people and identify common patterns of movement, such as speed, direction and type of movement, using parameters set in the simulator. People involved in the groups will be identified by RFID (Radio Frequency Identification) attached to his body. The movement of the crowd had its mathematical formalization based on parameters such as position of the group, number of people per group and duration of movement that define the characteristics necessary to simulate this scenario. From the formalization of the movement of the crowd, many data are collected at predetermined time intervals and interpreted by an algorithm, through the exchange of messages between sensors, estimates the crowd forming in the region defined as the target. In this work, were inserted charts and graphs that reflect the actual number of people moving towards the real target. These data are generated from the intense exchange of messages between sensors, obeying some parameters that favor established and the algorithm that estimates the crowd at the target formation at any given time. The accuracy of the prediction was measured by the amount of alarms issued that estimate and the formation of agglomerations of people in a given region. Thus, the identification of individuals by sensors is interpreted according to the possibility of formation of groups and their values disseminated by the network. The proposal is that this action will facilitate the process of decision making and thus help to characterize the formation of crowds. / O uso das Redes de Sensores sem Fio (RSSF) tem sido difundido em diversas áreas de pesquisa e aplicação. A proposta deste trabalho é um estudo sobre como utilizar sensores para monitorar pessoas em movimento, tendo uma RSSF como meio no qual a pesquisa deverá ocorrer, porém com o intuito de prever a formação de grupos em determinadas regiões. Para a realização deste trabalho a rede foi projetada e testada no simulador Ptolemy II, usando o protocolo ZigBee de comunicação, e os sensores foram posicionados de acordo com um sistema de coordenadas cartesianas. A RSSF deverá detectar as pessoas e identificar características comuns de movimento, como velocidade, direção e tipo de movimento, por meio de parâmetros configurados no simulador. As pessoas envolvidas nos grupos serão identificadas por etiquetas RFID (Radio Frequency Identification) presas ao seu corpo. O movimento de multidão teve sua formalização matemática baseada em parâmetros como posição do grupo, quantidade de pessoas por grupo e duração do movimento, que definem as características necessárias para a simulação desse cenário. A partir da formalização do movimento da multidão, vários dados foram coletados em intervalos de tempo previamente determinados e interpretados por um algoritmo que, por meio da troca de mensagens entre sensores, estima a formação de multidão na região definida como alvo. Neste trabalho, foram inseridos tabelas e gráficos que refletem o número real de pessoas que se deslocam em direção ao alvo real. Esses dados foram gerados a partir da intensa troca de mensagens entre os sensores, obedecendo alguns parâmetros estabelecidos e que favorecem o algoritmo que estima a formação de multidão no alvo, em determinado tempo. A acurácia da previsão foi medida pela quantidade de alarmes emitidos e que estimam a formação de aglomerações de pessoas em determinada região. Assim, a detecção de pessoas pelos sensores é interpretada de acordo com a possibilidade de formação de grupos, tendo seus valores disseminados pela rede. A proposta é que essa ação facilite o processo de tomada de decisão e, consequentemente, ajude na caracterização da formação de multidões
38

MAC-E-Filter characterization for PTOLEMY : a relic neutrino direct detection experiment

Strid, Carl-Fabian January 2019 (has links)
The cosmic neutrino background (CNB) can be composed of both active and hypothetical sterileneutrinos. At approximately one second after big bang, neutrinos decoupled from radiationand matter at a temperature of approximately one MeV. Neutrinos played an important role inthe origin and evolution of our universe and have been indirectly verified by cosmological dataon the BBN (Big Bang nucleosynthesis) of the Big Bang.It was Steven Weinberg in 1962 that first theorized on the direct detection of relic neutrinos.The signal of the relic neutrino capture on a tritium target can be observed by studying theendpoint of the electrons kinetic energy that are above the endpoint energy of the beta decayspectrum. The PTOLEMY project aims to archive direct detection of the relic neutrinobackground with a large tritium target of 100 gram, MAC-E-Filter, RF-tracking, Time of flighttracking and a cryogenic calorimetry.In this thesis the MAC-E-Filter have been simulated in two filter configurations. In the firstconfiguration, the electron were simulated five times in the filter. Two in the opposite sideof the detector, one in the middle, and two at the detector. In the second configuration theelectrons was simulated in the entrance solenoid at a fixed position of y = -0.19634954 m fromthe center of the filter and in random positions. Both multiple electrons and single electronswere simulated in the second configuration.In the single electron configuration the electron had a starting position of y = -0.19634954 mfrom the center of the filter, and an initial kinetic energy of 18.6 KeV. The first filter configurationsuccessfully accomplished to simulate the electron track, as the electron was reflectedback and forth between the entry and detector solenoid. The electric and magnetic field profilediered at the entry and detector solenoid. The second filter configuration successfully showedthat the electron will reach the end solenoid, when the filter length was 0.5 m. When the filterlength was increased to 0.7 m, then the electron was reflected in the middle of the filter. Thesimulation showed that the electron energy dropped below 1 eV from 18.6 KeV as the electronpropagated through the filter. The magnetic and electric fields decreased exponentially in thedirection of the detector solenoid. The Simulation of multiple electrons showed mixed resultsand would need more modifications in order to come to a final conclusion.
39

Artefatos e modelos da música na antiguidade ocidental / Musical artifacts and models in Western Antiquity

Gusmão, Cynthia Sampaio de 08 July 2015 (has links)
Este trabalho investiga o lugar da téchne no mundo antigo por meio dos instrumentos musicais, enquanto artefatos físicos e modelos matemáticos, geométricos e mecânicos. A escassez de informações sobre as técnicas de construção dos instrumentos leva a examinar outras atividades artesanais, especialmente aquelas ligadas à carpintaria e ao trabalho com metais. O exame da natureza do poder encantatório da música e sua relação com os instrumentos será realizado por meio da abordagem de figuras como as musas e os daimónes, e também da organização concebida pelos filósofos no período clássico. Apesar do lugar de inferioridade que importantes pensadores conferiram aos artesãos, evidências mostram que a téchne dos artífices marcou profundamente o pensamento grego. No que diz respeito à música, o papel do luthier foi fundamental na medida em que proporcionou o substrato material para desenvolvimentos na linguagem musical. Além dos artefatos, os modelos matemáticos, geométricos e mecânicos da música também nasceram nas oficinas. Ao serem dominados pelos músicos, tais rtefatos e modelos serão igualmente responsáveis por grandes transformações musicais. / This work investigates the Greek notion of téchne in the ancient world through its musical instruments, in the form of physical artifacts and mathematical, geometrical and mechanical models. Because of the lack of information about ancient lutherie, it examines other forms of craftsmanship, like carpentry and metallurgy. The inquire into the nature of the musical powers of music, and its relation to musical instruments, will be done by the examination of characters like muses and daimónes, and also of the organization models of the classical philosophers. Despite the inferior place that great philosophers give to the technicians, this study sustains that they had deeply influenced the Greek thought. Regarding music, its possible to say that the luthiers role was fundamental because the material foundation conducted developments in the musical language. Besides the artifacts, the mathematical, geometrical and mechanical musical models were born in the workshops. Artifacts and models, mastered by the musicians, will be equally responsible for the musical developments.
40

Firmicus Maternus' Mathesis and the intellectual culture of the fourth century AD

Mace, Hannah Elizabeth January 2017 (has links)
The focus of this thesis is Firmicus Maternus, his text the Mathesis, and their place in the intellectual culture of the fourth century AD. There are two sections to this thesis. The first part considers the two questions which have dominated the scholarship on the Mathesis and relate to the context of the work: the date of composition and Firmicus' faith at the time. Chapter 1 separates these questions and reconsiders them individually through an analysis of the three characters which appear throughout the text: Firmicus, the emperor, and the addressee Mavortius. The second part of the thesis considers the Mathesis within the intellectual culture of the fourth century. It examines how Firmicus establishes his authority as a didactic astrologer, with an emphasis on Firmicus' use of his sources. Chapter 2 examines which sources are credited. It considers the argument that Manilius is an uncredited source through an analysis of the astrological theory of the Mathesis and the Astronomica. In addition, the astrological theory of Ptolemy's Tetrabiblos is compared to the Mathesis to assess Firmicus' use of his named sources. The methods that Firmicus uses to assert his authority, including his use of sources, are compared to other didactic authors, both astrological or Late Antique in Chapter 3. This chapter examines whether Firmicus' suppression and falsifying of sources is found in other didactic literature. Chapter 4 considers possible reasons for the omission of Manilius' name and also the effect that this has had on intellectual culture and the place of the Mathesis within it.

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