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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

Evaluation de produits d'effacement sur un ensemble de consommateurs par modélisation bottom-up d'un parc de logements / Assessment of heating loads shedding at large scale through bottom-up modelling of housing stocks

Carloganu, Sinziana 08 December 2016 (has links)
Cette thèse se propose d’évaluer les produits d’effacement réalisés sur un ensemble de consommateurs, chacun étant défini par le triplet {bâtiment, systèmes, ménage}. On définit un produit d’effacement par la caractérisation de la déformation de la courbe de charge de l’ensemble des consommateurs suite à l’envoi d’un signal de contrôle (pilotage direct ou signal tarifaire).Deux dimensions ont été considérées dans le cadre de ce travail : l’étude des variables d’influence sur les effacements de consommation en s’appuyant sur des données issues d’expérimentations ainsi que l’élaboration d’un modèle global permettant de reproduire une partie de la diversité observée sur les courbes de charge des clients expérimentateurs.Afin d’analyser un échantillon {bâtiments, systèmes, ménages}, une attention particulière est portée à la dispersion des caractéristiques du bâti (enveloppes, expositions, ...) et aux éventuelles corrélations entre le ménage (mode de vie, choix des équipements, ...) et les systèmes (caractéristiques techniques), notamment pour l’usage "chauffage et climatisation".Un travail de réconciliation de données (issues de statistiques, de travaux sur la caractérisation des logements métropolitains, d’études sur les habitudes de vie des ménages, ...) a permis de proposer une première évaluation en simulation d’effacement de l’usage chauffage au périmètre d’un parc de quelques milliers de logements.L’approche bottom-up proposée permet ainsi de rendre compte de la diversité technique, fonctionnelle et d’origine comportementale de l’usage étudié. / This thesis aims at evaluating load curtailments packages over a set of electricity users, each being defined by the triolet {building, system, household}. We define a load curtailment package by the quantification of the load curve's deformation due to the emission of a control signal (direct control or price incentive).Two dimensions were considered through this work: first the study of the different variables' influence using experimental data, and secondly the construction of a global model which can effectively reproduce the diversity observed on experimental load curves.In order to analyse a sample {building, system, household}, the dispersion of the different caracteristics of the building (envelope, exposure,...) were carefully studied, as well as the possible links between the household (lifestyle, choice of household equipments,...) and the systems (technical caracteristics) especially for the electrical heaters and HVAC systems.We work to reconcile data from different sources (statistical data, data from research on urban building caracterization, on households' habits,...) and we are able to give a first evaluation of load curtailment products over the electrical heating usage in urban environment through numerical simulations of a few thousand housings. The bottom-up approach used accounts for the technical diversity, as well as the functional and behavioral diversity of the studied electrical usage.
22

Uma disciplina de análise e projeto para aplicações concorrentes, baseada no RUP

Godoi de Albuquerque Maranhão, Robson January 2005 (has links)
Made available in DSpace on 2014-06-12T16:01:13Z (GMT). No. of bitstreams: 2 arquivo7234_1.pdf: 3108647 bytes, checksum: 005c566b9ea912b4246e213ae0704e2f (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2005 / O desenvolvimento crescente de sistemas concorrentes e de tempo real vem provocando uma evolução nos conceitos e paradigmas da Engenharia de Software. Recentemente, entre outras abordagens, destacamos o surgimento de UML-RT, visando adaptar e estender as estruturas já consagradas de UML para os conceitos de concorrência e tempo real. Complementarmente, já existem modelos teóricos de concorrência e tempo real bem consolidados, como álgebra de processos, que contam com estratégias e ferramentas de validação, verificação e transformação de modelos. Por outro lado, processos de software bem definidos, que integrem estratégias formais de análise com orientações menos formais (mas sistemáticas) de desenvolvimento, são, ainda, negligenciados. O Rational Unified Process (RUP), um dos processos de desenvolvimento de software mais extensivamente usado e aceito, introduziu vários conceitos e orientações que objetivam sistematizar o desenvolvimento com UML-RT; no entanto, vários aspectos importantes e críticos de aplicações concorrentes, como a transformação de uma classe de análise (passiva) em uma classe ativa (cápsula ou processo), com um fluxo de execução independente, são tratados de forma superficial e informal; outros exemplos são a decomposição de cápsulas e a análise de uma aplicação com relação a propriedades clássicas de concorrência (como ausência de deadlock) ou específicas do negócio. As orientações fornecidas pelo RUP parecem sugerir que é simples garantir estes resultados, quando, na verdade, requerem grande atenção e conhecimento do desenvolvedor. O foco deste trabalho é a adaptação e extensão de uma das disciplinas mais afetadas do RUP, Análise e Projeto, a fim de integrar de forma mais detalhada e rigorosa os conceitos e implicações do desenvolvimento de aplicação concorrentes ao processo, incluindo a aplicação de leis de transformação de modelos, sugeridas em estratégias formais de desenvolvimento. A grosso modo, o objetivo pode ser resumido à adaptação do RUP ao paradigma de desenvolvimento baseado em modelos (MDE, Model Driven software Engineering). Apesar do foco em Análise e Projeto, outras disciplinas e fases são também revisadas. A proposta é validada através de sua aplicação a um estudo de caso sobre o projeto de um Sistema Automático de Produção SAP (Automatic Manufacturing System AMS), inicialmente explorado em [18]
23

UM FRAMEWORK BASEADO EM PADRÕES DE SEGURANÇA PARA TRANSFORMAÇÕES DE MODELOS / A FRAMEWORK BASED ON SECURITY PATTERNS FOR TRANSFORMATIONS OF MODELS

Prass, Fábio Sarturi 18 April 2012 (has links)
The increased automation in the process of systems development is becoming more popular in the current context because of the increased complexity. With this increasingly arise tools based on the idea of automatic code generation from models. As result of this complexity, information systems may have errors and vulnerabilities. So, there is a need for increasing the level of abstraction and automation in the software development processes, thereby allowing greater security in the application. These needs are answered by using the approaches of Model-Driven Engineering that allows the modeling and the application of transformations onto models aiming at obtaining software in an automatized way. This study proposes a framework based on security patterns oriented to model is proposed in this paper. This provides guidelines for implementing the model application abd the correct validation of using patterns. The security is implicitly included into the system through a transformation between models, which automatically encodes the security pattern, ensuring that the generated code is not susceptible to errors or changes in code. These transformations are defined through XML syntax and a set of rule implemented in Java and ATL language. They can be further executed in a unidirectional way, through the transformation application implemented to support the use of the proposed approach. It is also presented an example of model transformation for the Java platform. / O aumento da automatização nos processos de desenvolvimento de sistemas vem ganhando espaço no contexto atual devido ao aumento da complexidade. Com isto, cada vez mais surgem ferramentas baseadas na ideia de geração automática de código a partir de modelos. Por causa desta complexidade, os sistemas de informação estão sujeitos a erros e vulnerabilidades. Com isso, surgem as necessidades do aumento da automatização e do nível de abstração no desenvolvimento de software, permitindo assim maior segurança na aplicação. Essas necessidades são respondidas pela utilização da abordagem da Engenharia Dirigida por Modelos que permite a modelagem e aplicação de transformações sobre os modelos, visando à obtenção do software de forma automatizada. Este trabalho propõe um framework baseado em padrões de segurança orientado a modelo, fornecendo diretrizes para implementação do modelo e a validação correta do uso dos padrões. A segurança é inserida implicitamente no sistema por meio de transformação entre modelos e codificação automática, garantindo que a segurança não será violada em nenhum nível e não será suscetível a erros ou alterações do código. Estas transformações são definidas através de uma sintaxe XMI e um conjunto de regras implementadas em linguagem Java e ATL, e podem ser posteriormente executadas de maneira unidirecional, através da aplicação de transformações implementada para apoiar o uso da abordagem proposta. É apresentado também, um exemplo de transformação de modelos para a plataforma Java.
24

Uma abordagem dirigida por modelos para comunicação em tempo real / A model driven approach to real-time communication

Vieira, Marcelo Barros de Azevedo 09 October 2018 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-13T10:34:43Z No. of bitstreams: 2 Dissertação - Marcelo Barros de Azevedo Vieira - 2018.pdf: 2090852 bytes, checksum: cea29f7c5b0e3e434fef63a6866bc625 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-13T11:09:32Z (GMT) No. of bitstreams: 2 Dissertação - Marcelo Barros de Azevedo Vieira - 2018.pdf: 2090852 bytes, checksum: cea29f7c5b0e3e434fef63a6866bc625 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-13T11:09:32Z (GMT). No. of bitstreams: 2 Dissertação - Marcelo Barros de Azevedo Vieira - 2018.pdf: 2090852 bytes, checksum: cea29f7c5b0e3e434fef63a6866bc625 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-10-09 / The technological advances in recent years have allowed the development of new applications for communication. These applications allow multiple types of media to be switched between their users, with lower latency providing a better experience for the user. However, the development of applications for communication using general purpose languages has as a focus the development of the application and not the solution of the problems in a domain. In this way, domain-specific modeling languages, originated in Model-Driven Engineering, raise the level of abstraction and reduce the complexity of software development. Specificaly, modeling languages for the real-time communication domain aim to model applications that allow real-time communication among users, not only reducing the development time but also offering users the possibility of creating their own applications. The objective of this work was to propose a new communication modeling language, RBCML, which enables the definition of communication applications based on the roles that users play in a communication session, as well as their requirements in terms of the types of media and data that they can exchange. An implementation of the language was developed on top of the standards-based WebRTC platform in order to carry out evaluation experiments to demonstrate its usability and performance. / Os avanços tecnológicos ocorridos nos últimos anos, permitiram o desenvolvimento de novas aplicações para comunicação. Essas aplicações permitem que diversos tipos de mídia sejam usadas na comunicação entre os usuários, com menor latência e proporcionando uma melhor experiência para o usuário. No entanto, o desenvolvimento de aplicações para comunicação utilizando linguagens de propósito geral tem como característica o foco no desenvolvimento da aplicação e não na resolução de problemas no domínio. Isso motivou o surgimento de linguagens de modelagem específicas de domínio, originadas na Engenharia Dirigida por Modelos, que elevam o nível de abstração e reduzem a complexidade do desenvolvimento de software. Linguagens de modelagem específicas para o domínio de comunicação em tempo real têm como objetivo modelar aplicações que permitam a comunicação em tempo real, reduzindo o esforço no desenvolvimento deste tipo de aplicação e permitindo que os usuários criem suas próprias aplicações. O objetivo deste trabalho foi propor uma nova linguagem de comunicação, RBCML, que permite a definição de aplicações de comunicação com base nos papéis que os usuários desempenham nas sessões de comunicação, bem como em seus requisitos com respeito aos tipos de mídia e dados por meio dos quais a comunicação ocorre. Uma implementação da linguagem foi desenvolvida usando o padrão WebRTC para permitir a realização de experimentos para demonstrar sua usabilidade e desempenho.
25

Ingénierie dirigée par les modèles pour la conception et la mise en œuvre des réseaux de capteurs / Model-driven engineering for the design and implementation of sensor networks

Kifouche, Abdenour 11 September 2019 (has links)
Le cycle de vie d'un réseau de capteurs implique plusieurs étapes, telles que le dimensionnement du réseau, le développement de logiciels embarqués, la réalisation de matériels, des analyses et des simulations, le déploiement physique, l'exploitation des données et la maintenance du réseau. Tout au long de ce cycle, plusieurs outils spécifiques sont utilisés. Il est donc nécessaire de décrire manuellement les caractéristiques du réseau de capteurs dans chacun de ces outils en utilisant leurs propres langages. Il en résulte des coûts de développement importants et éventuellement des incohérences entre les différentes descriptions. Pour répondre à cette problématique, nous proposons une méthodologie basée sur l'approche MDE (Model Driven Engineering). Elle vise à couvrir toutes les étapes du cycle de vie d'un réseau de capteurs. Tous les concepts et les caractéristiques d'un réseau de capteurs sont décrits à l'aide d'un métamodèle. A partir de ce référentiel, il est possible d'extraire, à chaque étape du cycle de vie, une ou plusieurs facettes. Chaque facette est présentée et éditée avec l'outil le plus adéquat en créant des passerelles vers des outils tiers. Afin de mettre en œuvre la méthodologie proposée, un Framework est développé pour offrir un environnement de description multi-facettes : architecture réseau, architecture matérielle, architecture logicielle, flux de données et environnement physique. Un exemple de passerelle entre le Framework et un simulateur existant (Omnet++) a été développé pour estimer les performances des réseaux de capteurs. Le Framework permet la génération automatique des scripts de simulation ainsi que des codes sources pour les nœuds du réseau / The life cycle of a sensor network involves several steps, including network sizing, embedded software development, hardware design, analysis and simulation, physical deployment, data exploitation, and network maintenance. Throughout this cycle, several specific tools are used. It is therefore necessary to manually describe the characteristics of the sensor network in each of these tools using their own languages. This results in significant development costs and potential inconsistencies between the different descriptions. To address this problem, we propose a methodology based on model driven engineering approach. It aims to cover all life cycle steps of a sensor network. All concepts and characteristics of a sensor network are described using a metamodel. From this referential, it is possible to extract, at each step of the life cycle, one or more facets. Each facet is presented and edited with the most appropriate tool by creating gateways to external tools.In order to implement the proposed methodology, a Framework is developed to provide a multi-facets environment: network architecture, hardware architecture, software architecture, data flow and physical environment. An example of a gateway between the Framework and an existing simulator (Omnet++) has been developed to estimate sensor network performances. The Framework allows automatic generation of simulation scripts as well as source codes for network nodes
26

Diversidade de pteridófitas em gradientes de altitude na Mata Atlântica do estado do Paraná / Diversity of pteridophytes along altitudinal gradients in the Atlantic Rain Forest of the Paraná State, Brazil

Paciencia, Mateus Luís Barradas 22 August 2008 (has links)
A fim de se compreender como varia a diversidade de pteridófitas em função do aumento da elevação do terreno e quais os potenciais mecanismos responsáveis pelas mudanças na riqueza e na abundância de espécies ao longo do gradiente de altitude, foram estudadas as vertentes leste-nordeste de três montanhas do complexo costeiro da Serra do Mar, no Estado do Paraná Serra da Graciosa, Pico do Marumbi e Serra da Prata. As amostragens foram conduzidas em 10 parcelas de 10m x 60m, ao longo do gradiente florestal altitudinal de cada montanha. Os sítios de amostragem foram distribuídos em intervalos aproximados de 200 m em elevação, desde localidades próximas à linha de costa (áreas de Restinga arbórea e de Floresta Ombrófila Densa de Terras Baixas, entre 0-10 m de altitude) até os pontos mais altos das serras de (1.500 m.s.n.m., aproximadamente). Considerando todos os sítios, foram registradas 166 espécies, distribuídas em 61 gêneros e 21 famílias. Enquanto Hymenophyllaceae, Lycopodiaceae e as gramitidóides são observadas em altitudes mais elevadas, Polypodiaceae, Cyatheaceae, Thelypteridaceae, Lomariopsidaceae e Schizaeceae tendem a ocorrer em localidades mais baixas. Os resultados indicaram que existe um forte efeito da altitude sobre a determinação da riqueza de espécies, tanto em escala local (cada montanha, individualmente) quanto em escala regional (conjunto das três montanhas): a riqueza interpolada e a observada variaram segundo uma curva em forma de sino, ao longo dos gradientes, atingindo um pico a 800-1.000 m.s.n.m.. Análises de regressão múltipla evidenciaram que os principais fatores abióticos capazes de explicar o padrão de riqueza encontrado foram, em ordem decrescente, as restrições geométricas verificadas nos extremos do gradiente (modelo nulo baseado no efeito do domínio central MDE), a estrutura da floresta e a constituição físico-química do solo, para =0,05. Essas três variáveis, juntas, foram capazes de explicar 46,7% a 95,4% da variação da riqueza de espécies, dependendo da escala em questão. A riqueza interpolada foi mais bem amplamente explicada pelo MDE, enquanto que a riqueza observada foi explicada, primordialmente, pelos solos e pela estrutura florestal (valores resumidos segundo os primeiros eixos de análises não-métricas de escalas multidimensionais NMDS). A abundância, por sua vez, variou apenas no gradiente de altitude da Serra da Prata, apresentando relações positivas com a complexidade estrutural da floresta. Conforme vem sendo discutido na literatura para diversos grupos biológicos, os MDE mostraram-se os principais fatores determinantes da riqueza de espécies, atribuindo um forte peso à estocasticidade na explicação de padrões de distribuição das espécies. / In order to better understand how diversity of pteridophytes varies in function of the terrain elevation and what are the potential mechanisms driving species richness and abundance changes, the eastern-northeastern slopes of three mountains at Serra do Mar, State of Paraná, Brazil Serra da Graciosa, Marumbi Peak and Serra da Prata were studied. The surveys were done in 10 plots of 10m x 60m along forested altitudinal gradient at each mountain. Sites were distributed on 200 m-elevation intervals, from near sea level (forests on sandbanks Restinga and Lowland Rain Forest, between 0-10 m-elevation) up to the tops of mountains (1,500 m a.s.l., approximately). Considering all sites combined, we found 166 species of pteridophytes from 61 genera and 21 families. While Hymenophyllaceae, Lycopodiaceae, and grammitids are mainly observed at high elevations, Polypodiaceae, Cyatheaceae, Thelypteridaceae, Lomariopsidaceae, and Schizaceae tend to occur at lower places of the mountains. Results showed a strong altitudinal effect over the pteridophyte species richness for both local and regional scales (the three mountains separately or treated as a set): both interpolated and observed species richness had described a hump-shaped pattern along all gradients, peaking at 800-1,000 m a.s.l. Multiple regression analysis provided evidences that the main factors able to explain richness pattern were, in decreasing order, the geometric constraints noticed in the ends of the gradient (Mid-Domain Effect - MDE), the forest structure, and the physiochemical constitution of the soil, for =0.05. These three variables together explained 46.7% to 95.4% of species richness variation, depending on the scale. Interpolated richness was better explained by MDE, while the observed richness was firstly explained by soils and forest structure (summarized by the first dimensions of the non-metric multidimensional scaling analysis NMDS). Moreover, the abundance varied only in the altitudinal gradient at Serra da Prata, where a positive relationship to the structural complexity of the forest was remarked. According to the present results and to data found in the current literature for many taxonomic groups, MDE has been the most important factor determining the species richness. Thus, sthocasticity can get an original play in species distribution patterns.
27

ESTIMATIVA DOS PARÂMETROS GENÉTICOS DE CARACTERES MORFOMÉTRICOS EM GUPPY (Poecilia reticulata)

Gomide, Jefferson Mendes 17 December 2008 (has links)
Made available in DSpace on 2016-08-10T10:39:23Z (GMT). No. of bitstreams: 1 Jefferson Mendes Gomide.pdf: 1020338 bytes, checksum: 0191262649084f3b90170c5b28b340dd (MD5) Previous issue date: 2008-12-17 / The invasion of new environments is related to the genetic variability of the species. The guppy (Poecilia reticulata) is a species introduced accidentally or artificially, arisen from different populations of captivity around the world. In some countries, these introductions are made repeatedly, particularly to control the growth of disease-transmitting mosquitoes in small lakes and streams in tropical countries. The Guppy is feeding the larvae of mosquitoes, preventing it from coming into adult life. Because of the need to obtain a better understanding of the differentiation of introduced populations, and this may reduce the impact of the introduction of exotic species, since it is the third leading cause of extinction of native species, three populations in different cities of the state of Goias were collected, and their metric features analyzed. The review sought to determine the rate of divergence among populations of free life, which contribute to the understanding of the process of colonization of natural environments by this alien species. The results indicated that the divergence between the populations analyzed, for most of the features is very large, ie the rate of divergence is greater than expected by neutral evolution, so that directional selection is expected to be acting on these characteristics. / A invasão de novos ambientes se relaciona com a variabilidade genética das espécies. O Guppy (Poecilia reticulata) é uma destas espécies introduzidas acidentalmente ou artificialmente, advindo de várias populações de cativeiro em todo o mundo. Em alguns países, estas introduções se deram várias vezes, particularmente para o controle do crescimento de mosquitos transmissores de doenças, em lagos e pequenos riachos nos países tropicais. O Guppy se alimenta das larvas desses mosquitos, impedindo que cheguem à fase adulta. Devido à necessidade de se obter uma maior compreensão da diferenciação de populações introduzidas, e com isto poder reduzir o impacto da introdução de espécies exóticas, já que é a terceira causa de extinção de espécies nativas, foram coletadas três populações em cidades diferentes do estado de Goiás, e as suas características métricas analisadas. A análise procurou determinar a taxa de divergência, entre populações de vida livre, que contribuirá para a compreensão do processo de colonização dos ambientes naturais por esta espécie exótica. Os resultados indicaram que a divergência entre as populações analisadas, para a maioria das características é muito grande, ou seja, a taxa de divergência é maior do que a esperada pela evolução neutra, de modo que seleção direcional deve estar atuando sobre estas características.
28

Diversidade de pteridófitas em gradientes de altitude na Mata Atlântica do estado do Paraná / Diversity of pteridophytes along altitudinal gradients in the Atlantic Rain Forest of the Paraná State, Brazil

Mateus Luís Barradas Paciencia 22 August 2008 (has links)
A fim de se compreender como varia a diversidade de pteridófitas em função do aumento da elevação do terreno e quais os potenciais mecanismos responsáveis pelas mudanças na riqueza e na abundância de espécies ao longo do gradiente de altitude, foram estudadas as vertentes leste-nordeste de três montanhas do complexo costeiro da Serra do Mar, no Estado do Paraná Serra da Graciosa, Pico do Marumbi e Serra da Prata. As amostragens foram conduzidas em 10 parcelas de 10m x 60m, ao longo do gradiente florestal altitudinal de cada montanha. Os sítios de amostragem foram distribuídos em intervalos aproximados de 200 m em elevação, desde localidades próximas à linha de costa (áreas de Restinga arbórea e de Floresta Ombrófila Densa de Terras Baixas, entre 0-10 m de altitude) até os pontos mais altos das serras de (1.500 m.s.n.m., aproximadamente). Considerando todos os sítios, foram registradas 166 espécies, distribuídas em 61 gêneros e 21 famílias. Enquanto Hymenophyllaceae, Lycopodiaceae e as gramitidóides são observadas em altitudes mais elevadas, Polypodiaceae, Cyatheaceae, Thelypteridaceae, Lomariopsidaceae e Schizaeceae tendem a ocorrer em localidades mais baixas. Os resultados indicaram que existe um forte efeito da altitude sobre a determinação da riqueza de espécies, tanto em escala local (cada montanha, individualmente) quanto em escala regional (conjunto das três montanhas): a riqueza interpolada e a observada variaram segundo uma curva em forma de sino, ao longo dos gradientes, atingindo um pico a 800-1.000 m.s.n.m.. Análises de regressão múltipla evidenciaram que os principais fatores abióticos capazes de explicar o padrão de riqueza encontrado foram, em ordem decrescente, as restrições geométricas verificadas nos extremos do gradiente (modelo nulo baseado no efeito do domínio central MDE), a estrutura da floresta e a constituição físico-química do solo, para =0,05. Essas três variáveis, juntas, foram capazes de explicar 46,7% a 95,4% da variação da riqueza de espécies, dependendo da escala em questão. A riqueza interpolada foi mais bem amplamente explicada pelo MDE, enquanto que a riqueza observada foi explicada, primordialmente, pelos solos e pela estrutura florestal (valores resumidos segundo os primeiros eixos de análises não-métricas de escalas multidimensionais NMDS). A abundância, por sua vez, variou apenas no gradiente de altitude da Serra da Prata, apresentando relações positivas com a complexidade estrutural da floresta. Conforme vem sendo discutido na literatura para diversos grupos biológicos, os MDE mostraram-se os principais fatores determinantes da riqueza de espécies, atribuindo um forte peso à estocasticidade na explicação de padrões de distribuição das espécies. / In order to better understand how diversity of pteridophytes varies in function of the terrain elevation and what are the potential mechanisms driving species richness and abundance changes, the eastern-northeastern slopes of three mountains at Serra do Mar, State of Paraná, Brazil Serra da Graciosa, Marumbi Peak and Serra da Prata were studied. The surveys were done in 10 plots of 10m x 60m along forested altitudinal gradient at each mountain. Sites were distributed on 200 m-elevation intervals, from near sea level (forests on sandbanks Restinga and Lowland Rain Forest, between 0-10 m-elevation) up to the tops of mountains (1,500 m a.s.l., approximately). Considering all sites combined, we found 166 species of pteridophytes from 61 genera and 21 families. While Hymenophyllaceae, Lycopodiaceae, and grammitids are mainly observed at high elevations, Polypodiaceae, Cyatheaceae, Thelypteridaceae, Lomariopsidaceae, and Schizaceae tend to occur at lower places of the mountains. Results showed a strong altitudinal effect over the pteridophyte species richness for both local and regional scales (the three mountains separately or treated as a set): both interpolated and observed species richness had described a hump-shaped pattern along all gradients, peaking at 800-1,000 m a.s.l. Multiple regression analysis provided evidences that the main factors able to explain richness pattern were, in decreasing order, the geometric constraints noticed in the ends of the gradient (Mid-Domain Effect - MDE), the forest structure, and the physiochemical constitution of the soil, for =0.05. These three variables together explained 46.7% to 95.4% of species richness variation, depending on the scale. Interpolated richness was better explained by MDE, while the observed richness was firstly explained by soils and forest structure (summarized by the first dimensions of the non-metric multidimensional scaling analysis NMDS). Moreover, the abundance varied only in the altitudinal gradient at Serra da Prata, where a positive relationship to the structural complexity of the forest was remarked. According to the present results and to data found in the current literature for many taxonomic groups, MDE has been the most important factor determining the species richness. Thus, sthocasticity can get an original play in species distribution patterns.
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Concevoir et partager des workflows d’analyse de données : application aux traitements intensifs en bioinformatique / Design and share data analysis workflows : application to bioinformatics intensive treatments

Moreews, François 11 December 2015 (has links)
Dans le cadre d'une démarche d'Open science, nous nous intéressons aux systèmes de gestion de workflows (WfMS) scientifiques et à leurs applications pour l'analyse de données intensive en bioinformatique. Nous partons de l'hypothèse que les WfMS peuvent évoluer pour devenir des plates-formes pivots capables d'accélérer la mise au point et la diffusion de méthodes d'analyses innovantes. Elles pourraient capter et fédérer autour d'une thématique disciplinaire non seulement le public actuel des consommateurs de services mais aussi celui des producteurs de services. Pour cela, nous considérons que ces environnements doivent à la fois être adaptés aux pratiques des scientifiques concepteurs de méthodes et fournir un gain de productivité durant la conception et le traitement. Ces contraintes nous amènent à étudier la capture rapide des workflows, la simplification de l'intégration des tâches techniques, comme le parallélisme nécessaire au haut-débit, et la personnalisation du déploiement. Tout d'abord, nous avons défini un langage graphique DataFlow expressif, adapté à la capture rapide des workflows. Celui-ci est interprétable par un moteur de workflows basé sur un nouveau modèle de calcul doté de performances élevées, obtenues par l'exploitation des multiples niveaux de parallélisme. Nous présentons ensuite une approche de conception orientée modèle qui facilite la génération du parallélisme de données et la production d'implémentations adaptées à différents contextes d'exécution. Nous décrivons notamment l'intégration d'un métamodèle des composants et des plates-formes, employé pour automatiser la configuration des dépendances des workflows. Enfin, dans le cas du modèle Container as a Service (CaaS), nous avons élaboré une spécification de workflows intrinsèquement diffusable et ré-exécutable. L'adoption de ce type de modèle pourrait déboucher sur une accélération des échanges et de la mise à disposition des chaînes de traitements d'analyse de données. / As part of an Open Science initiative, we are particularly interested in the scientific Workflow Management Systems (WfMS) and their applications for intensive data analysis in bioinformatics. We start from the assumption that WfMS can evolve to become efficient hubs able to speed up the development and the dissemination of innovative analysis methods. These software platforms could rally and unite not only the current stakeholders, who are service consumers, but also the service producers, around a disciplinary theme. We therefore consider that these environments must be both adapted to the practices of the scientists who are method designers and also enhanced with increased productivity during design and treatment. These constraints lead us to study the rapid capture of workflows, the simplification of technical tasks integration, like parallelisation and the deployment customization. First, we define an expressive graphic worfklow language, adapted to the quick capture of workflows. This is interpreted by a workflow engine based on a new model of computation with high performances obtained by the use of multiple levels of parallelism. Then, we present a Model-Driven design approach that facilitates the data parallelism generation and the production of suitable implementations for different execution contexts. We describe in particular the integration of a components and platforms meta-model used to automate the configuration of workflows’ dependencies. Finally, in the case of the cloud model Container as a Service (CaaS), we develop a workflow specification intrinsically re-executable and readily disseminatable. The adoption of this kind of model could lead to an acceleration of exchanges and a better availability of data analysis workflows.
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Model-oriented Programming with Bigraphical Reactive Systems: Theory and Implementation

Grzelak, Dominik 25 April 2024 (has links)
It is well-recognized among computer scientists that prospective informatics systems will become more and more complex and will increasingly accumulate non-linear behaviour that is difficult to orchestrate, to configure, and to reason about. Certainly, large-scale mobile computing systems will challenge our understanding, similar to climate systems, bio-chemical systems, physical systems, or social networks. This suggests a rigorous formalization and study of non-trivial computational systems. In this regard, bigraphs are a groundbreaking novel theory for distributed and parallel systems, treating mobile locality and mobile interaction as first-class citizens. The theory was devised by Robin Milner as a process algebra with rewrite capabilities based on graph equations and an algebraic type system. Bigraphs have been the subject of extensive investigation from various perspectives, including agent-based modelling, cyber-physical games, language construction, graph rewriting, and as a unifying metamodel for other rewrite theories and process calculi, but particularly in the context of the categorical reactive system approach. In this approach, a labelled transition system, over which bisimilarity is a congruent equivalence relation, is generated from reduction semantics that can be freely specified. The bigraph theory treats two-dimensional graphs as arrows and their interfaces as objects while category theory provides the underlying mathematical framework for their axiomatization. Fortunately, category theory makes the theory future-proof, competitive and extensible. The recently developed categorical concepts of relative and idempotent pushouts facilitate the categorical construction of minimal context labels enabling the development of a behavioural theory, where bisimulation is a congruence. The metamodel character of bigraphs enables the comparison of other formalisms and algebraic theories of concurrent computation at a very abstract level, thus, regaining their behavioural theory and computational notion, with the ultimate goal of exploiting synergies. Indeed, bigraphs are much more than a computational model for understanding, analysing, and verifying systems. They provide both a formal and practical foundation for context-oriented reactive system modelling and programming languages. Consequently, the development of software solutions based on the bigraph theory necessitates suitable tools, frameworks, and languages for putting bigraphs into practice. These tools are essential for evaluating the model’s effectiveness in both academic research and the software industry. Only this permits rigorous testing of the theory. But moreover, reaching this goal is the result of the motivation to lower the barrier to entry for model-driven context-adaptive programming using the bigraph theory. So far, several tools and libraries have been developed to model and simulate bigraphical reactive systems. These tools can roughly be referred to as bigraphical calculators and are meant for experimentation and comprehension of the theory. Without them, this work could not have been written. However, we elevate the initial efforts to a level more conducive to enable advanced bigraphical software engineering practises. Therefore, the Bigraph Toolkit Suite was developed—a collection of tools and methods for the research and development of reactive systems for real-world applications. The suite consists of model-based integration frameworks, architectural guidelines, integrated development environments, command-line tools, and an uncomplicated language engineering workbench with an extensible grammar and interpreter. Each product of the Bigraph Toolkit Suite serves a distinct function, ranging from the manipulation and simulation of bigraphs to bigraphical language engineering and distributed storage of bigraph models. The tools are finely tuned to each other via a common metamodel, which facilitates implementation of novel bigraphical tool chains as well as the integration of arbitrary tools and public programming interfaces. Certainly, the following ambient question paved the path of this research: Is there a formalism or theory that supports context modelling, computation and verification, and that can be used as a programming language? The work shows that bigraphs can be used to lay such a foundation to regain the understanding of new informatics systems, with model-driven engineering contributing to this. According to this, the latent objective of this work is the cross-fertilization process of model-driven engineering and bigraphical reactive systems on a practical basis. A discussion is developed of whether there is evidence to support the view that the presence of MDE-related model operations and practices may be related to bigraph operations and vice versa. A relation can be established by a consistent and complete canonical mapping on the x-axis based on a systematic four-layer metamodelling framework; and on the y-axis between three different yet interoperable technical spaces. Thus, the result of this thesis is developed along two axes from a strict software engineering perspective. On the one hand, practical observations of the bigraph theory are provided about other graph structures, categories and model-driven operations. On the other, a novel software ecosystem for bigraphical reactive systems is provided together with several generic experimental approaches such as event-based execution of sub-bigraphical reactive systems. The theory already stimulated much other research works and therefore advancing fundamental computer science, this work may additionally—hopefully, the reader will agree—solidify and advance bigraphical research.:1 Introduction 1.1 Background and Motivation 1.1.1 Typical Application Scenarios 1.1.2 The Dilemma of Complex Reactive Systems 1.2 Field of Work 1.2.1 Reactive Systems 1.2.2 Model-driven Engineering 1.2.3 Context Adoption in Software: A Novel Taxonomy 1.3 Research Project 1.3.1 Hypothesis 1.3.2 Research Aim 1.3.3 Research Objectives 1.3.4 Contributions 1.4 Outline 2 The Theory of Bigraphical Reactive Systems for Software Engineers 2.1 Graph Theory: Basic Notation 2.2 Categories for Context-adaptive Software 2.2.1 Elementary Category Theory 2.2.2 Reactive System Categories: s-category and spm category 2.2.3 Type Graphs and Type Morphisms 2.2.4 Observations 2.3 On the Static Structure of Bigraphs 2.3.1 Signatures 2.3.2 Pure Bigraphs: Place Graphs and Link Graphs 2.3.3 Compositional Structures: Interfaces and Operators 2.3.4 Algebra of Bigraphs 2.3.5 Graphical s-categories 2.4 Type Systems and Sortings 2.4.1 Basic Terminology 2.4.2 Sortings and Bigraphs 2.5 Dynamics of Reactive Systems 2.5.1 Operational Semantics of Reactive Systems 2.5.2 Reactive System Theory: General Categories 2.5.3 Bigraphical Reactive Systems 2.5.4 Labelled Transition Systems 2.5.5 Behavioural Equivalences 2.5.6 Observations 2.6 Formal Verification 2.6.1 Model Checking in Detail 2.6.2 Properties of Sequential and Parallel Programs 2.6.3 State-Space Explosion Problem 3 Model-driven Concepts in Bigraphs 3.1 A Canonical Mapping: From Bigraphs to Ecore 3.1.1 The Four-layer Metamodelling Framework Revisited 3.1.2 Formal Relations between Bigraphs, Type Graphs and Ecore 3.1.3 Model Constraints at the 𝑀1 and 𝑀0 layer 3.1.4 Design Level Variability and Extensibility 3.2 Bigraphical Models: Specification and Generation 3.2.1 Typing and Subtyping via (Un-)Sorted Signatures and their Instantiation from Metamodels 3.2.2 Bigraphs and their Instantiation from Metamodels 3.2.3 Observations 3.3 Modelling Techniques: A Bigraphical Perspective 3.3.1 Bigraphs and UML Class Diagrams 3.3.2 Signature Operations 3.3.3 Abstraction 3.3.4 View Modelling with Place Graphs 3.4 Design Patterns for Implementing Variation Points 3.5 Summary 4 Bigraph Toolkit Suite: A Complete Software Development Ecosystem 4.1 The Bigraphical Tool Landscape 4.1.1 High-level Architecture 4.1.2 Overview of the Constituents 4.1.3 Design Qualities 4.1.4 Project Organisation 4.2 Modelling and Visualization 4.2.1 Programmatic Approach: Builders and Operators 4.2.2 Domain-specific Language 4.2.3 Converters: Model Translations 4.2.4 Visual Modelling: Bigellor 4.3 Simulation and Verification 4.3.1 Specification of BRSs 4.3.2 Implementation Aspects: Entity Classes 4.3.3 Implementation Aspects: Business Classes 4.3.4 Model Checking Algorithm 4.3.5 Coordination of BRSs: Higher-order Execution Strategies 4.3.6 Error Handling: Chain of Responsibility and Exceptions 4.4 Bigraphical Domain-specific Language 4.4.1 Overview of BDSL’s Grammar 4.4.2 Language Features 4.4.3 Interpreter: Decoupling the Grammar from Application-Specific Code 4.4.4 BDSL-CLI: A Command-line Interpreter Tool for BDSL 4.4.5 Theia: An Integrated Development Environment for BDSL 4.5 Persistence: Distributed Model Storage 4.5.1 Basic Filesystem Storage Facilities 4.5.2 Spring Data CDO: Spring Data and Connected Data Objects 4.5.3 Arbitrary Hierarchical Layouts for Bigraphical Models 4.5.4 Event Listeners 4.6 Performance and Quality Analysis 4.6.1 Functional Tests 4.6.2 Dependency Analysis 4.6.3 Runtime Analysis 4.7 Summary 5 Related Work: The Bigraphical Tool Landscape 5.1 A Lightweight Qualitative Comparison Framework 5.1.1 Conceptual Foundations 5.1.2 Considerations 5.2 Method and Tool Candidates 5.2.1 Selection Process 5.2.2 Excluded Tool Candidates 5.2.3 Tool Overview 5.3 Results 5.3.1 jLibBig 5.3.2 bigraphspace 5.3.3 BigRED 5.3.4 BigM 5.3.5 BigraphER 5.3.6 BigMC 5.3.7 BPL Tool 5.3.8 BiGMTE 5.3.9 DBtk 5.4 Evaluation and Discussion 5.4.1 Assessment Criteria 5.4.2 Comparison of Non-Functional Aspects 5.4.3 Comparison of Functional Aspects 5.4.4 Term Language 5.4.5 Interoperability 5.4.6 Accessibility 5.5 Summary 6 Conclusion List of Figures List of Tables List of Listings Bibliography Online Resources Appendices A Theoretical Addendum B Design Patterns, Techniques and Technologies C Code Listings: Related Work Abbreviations

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