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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.
231

Método de ajuste para MPC baseado em multi-cenários para sistemas não quadrados

Santos, José Eduardo Weber dos January 2016 (has links)
A utilização de controladores preditivos multivariáveis na indústria de processos cresceu significativamente nos últimos anos principalmente devido à versatilidade e a confiabilidade que essa ferramenta proporciona em termos de controle avançado. No entanto, aspectos relacionados à aplicação prática do que vem sendo desenvolvido no meio acadêmico possui pouca difusão na indústria devido às configurações clássicas adotadas, como sistemas quadrados (com o mesmo número de variáveis controladas e manipuladas), modelos lineares, utilização de setpoint e etc. diferindo daquilo que está disponível e é amplamente utilizado industrialmente: sistemas não-quadrados (geralmente com mais variáveis controladas do que manipuladas), modelos não-lineares e utilização de soft-constraints. Esse trabalho propõe uma metodologia para ajuste dos parâmetros presentes em um controlador preditivo, atento à variedade de algoritmos presentes na indústria de processos. Essa metodologia se baseia na obtenção do melhor desempenho alcançável para cada cenário de um modelo global do processo, atendendo as restrições de Número de Desempenho Robusto relativo (rRPN), Máxima Sensibilidade e restrições nas ações de controle. Baseado em um desempenho que é alcançável, o modelo linear global é escalonado (assim como a planta não-linear) e os pesos que levam o sistema para a melhor condição operacional são estimados. Essa técnica abrange controladores operando em faixas e/ou setpoint e configurações não-quadradas, i.e., com mais variáveis controladas do que manipuladas. A abordagem proposta foi testada em uma planta de quatro tanques esféricos com aquecimento apresentando resultados coerentes, corroborando seu potencial de aplicação industrial. / Due to their versatility and reliability, Model Predictive Controllers (MPCs) are the standard solution for advanced process control in the process industry. However, there is a gap between the academic developments and the actual industrial applications, since the most academic studies focus on systems working with set-points and same number of manipulated and controlled variables, whereas the industrial application cope with non-squared configuration usually with several controlled variables in ranging and a reduced number of manipulated variables. This work proposes a tuning methodology for the countable parameters presents in a typical industrial predictive controller, considering the variety of the algorithms presents commercially in the process industry. This methodology is based on the estimation of the best attainable performance for each scenario of the global model of the process, constrained by the relative Robust Performance Number (rRPN), Maximal Sensitivity and restrictions in the control actions. Based on a performance that is attainable, the linear global model is scaled (and the non-linear) and the weights that lead the system to the best operational condition are estimated. This technique covers controllers operating in zones of control and/or set-point tracking and non-square configurations, i.e., with more controlled variables than manipulated. The proposed approach was tested in a Quadruple-Spherical tanks heating system presenting coherent results indicating its potential for industrial applications.
232

Water Efficiency in Agriculture: a Study of the Adoption of Water Conserving and Profitable Irrigation Technology in Arizona.

January 2014 (has links)
abstract: With the projected population growth, the need to produce higher agricultural yield to meet projected demand is hindered by water scarcity. Out of many the approaches that could be implemented to meet the water gap, intensification of agriculture through adoption of advanced agricultural irrigation techniques is the focus for this research. Current high water consumption by agricultural sector in Arizona is due to historical dominance in the state economy and established water rights. Efficiency gained in agricultural water use in Arizona has the most potential to reduce the overall water consumption. This research studies the agricultural sector and water management of several counties in Arizona (Maricopa, Pinal, and Yuma). Several research approaches are employed: modeling of agricultural technology adoption using replicator dynamics, interview with water managers and farmers, and Arizona water management law and history review. Using systems thinking, the components of the local farming environment are documented through socio-ecological system/robustness lenses. The replicator dynamics model is employed to evaluate possible conditions in which water efficient agricultural irrigation systems proliferate. The evaluation of conditions that promote the shift towards advanced irrigation technology is conducted through a combination of literature review, interview data, and model analysis. Systematic shift from the currently dominant flood irrigation toward a more water efficient irrigation technologies could be attributed to the followings: the increase in advanced irrigation technology yield efficiency; the reduction of advanced irrigation technology implementation and maintenance cost; the change in growing higher value crop; and the change in growing/harvesting time where there is less competition from other states. Insights learned will further the knowledge useful for this arid state's agricultural policy decision making that will both adhere to the water management goals and meet the projected food production and demand gap. / Dissertation/Thesis / Masters Thesis Sustainability 2014
233

The Semiotic Nature of Power in Social-Ecological Systems

January 2017 (has links)
abstract: Anderies (2015); Anderies et al. (2016), informed by Ostrom (2005), aim to employ robust feedback control models of social-ecological systems (SESs), to inform policy and the design of institutions guiding resilient resource use. Cote and Nightingale (2012) note that the main assumptions of resilience research downplay culture and social power. Addressing the epistemic gap between positivism and interpretation (Rosenberg 2016), this dissertation argues that power and culture indeed are of primary interest in SES research. Human use of symbols is seen as an evolved semiotic capacity. First, representation is argued to arise as matter achieves semiotic closure (Pattee 1969; Rocha 2001) at the onset of natural selection. Guided by models by Kauffman (1993), the evolution of a symbolic code in genes is examined, and thereon the origin of representations other than genetic in evolutionary transitions (Maynard Smith and Szathmáry 1995; Beach 2003). Human symbolic interaction is proposed as one that can support its own evolutionary dynamics. The model offered for wider dynamics in society are “flywheels,” mutually reinforcing networks of relations. They arise as interactions in a domain of social activity intensify, e.g. due to interplay of infrastructures, mediating built, social, and ecological affordances (An- deries et al. 2016). Flywheels manifest as entities facilitated by the simplified interactions (e.g. organizations) and as cycles maintaining the infrastructures (e.g. supply chains). They manifest internal specialization as well as distributed intention, and so can favor certain groups’ interests, and reinforce cultural blind spots to social exclusion (Mills 2007). The perspective is applied to research of resilience in SESs, considering flywheels a semiotic extension of feedback control. Closer attention to representations of potentially excluded groups is justified on epistemic in addition to ethical grounds, as patterns in cul- tural text and social relations reflect the functioning of wider social processes. Participatory methods are suggested to aid in building capacity for institutional learning. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2017
234

Diffusion in Networks: Source Localization, History Reconstruction and Real-Time Network Robustification

January 2018 (has links)
abstract: Diffusion processes in networks can be used to model many real-world processes, such as the propagation of a rumor on social networks and cascading failures on power networks. Analysis of diffusion processes in networks can help us answer important questions such as the role and the importance of each node in the network for spreading the diffusion and how to top or contain a cascading failure in the network. This dissertation consists of three parts. In the first part, we study the problem of locating multiple diffusion sources in networks under the Susceptible-Infected-Recovered (SIR) model. Given a complete snapshot of the network, we developed a sample-path-based algorithm, named clustering and localization, and proved that for regular trees, the estimators produced by the proposed algorithm are within a constant distance from the real sources with a high probability. Then, we considered the case in which only a partial snapshot is observed and proposed a new algorithm, named Optimal-Jordan-Cover (OJC). The algorithm first extracts a subgraph using a candidate selection algorithm that selects source candidates based on the number of observed infected nodes in their neighborhoods. Then, in the extracted subgraph, OJC finds a set of nodes that "cover" all observed infected nodes with the minimum radius. The set of nodes is called the Jordan cover, and is regarded as the set of diffusion sources. We proved that OJC can locate all sources with probability one asymptotically with partial observations in the Erdos-Renyi (ER) random graph. Multiple experiments on different networks were done, which show our algorithms outperform others. In the second part, we tackle the problem of reconstructing the diffusion history from partial observations. We formulated the diffusion history reconstruction problem as a maximum a posteriori (MAP) problem and proved the problem is NP hard. Then we proposed a step-by- step reconstruction algorithm, which can always produce a diffusion history that is consistent with the partial observations. Our experimental results based on synthetic and real networks show that the algorithm significantly outperforms some existing methods. In the third part, we consider the problem of improving the robustness of an interdependent network by rewiring a small number of links during a cascading attack. We formulated the problem as a Markov decision process (MDP) problem. While the problem is NP-hard, we developed an effective and efficient algorithm, RealWire, to robustify the network and to mitigate the damage during the attack. Extensive experimental results show that our algorithm outperforms other algorithms on most of the robustness metrics. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2018
235

Analyse et amélioration de la robustesse des circuits asynchrones QDI / Robustness analysis and improvement of QDI self-timed circuits

Ouchet, Florent 02 December 2011 (has links)
La conception de circuits intégrés asynchrones, notamment de circuits QDI (Quasi-Delay Insensitive), offrent la possibilité de disposer de circuits très robustes aux conditions environnementales (tension, température) ainsi qu'aux variations des procédés de fabrication. Ces bonnes propriétés sont dues à une conception ne comportant pas d'hypothèses temporelles à l'exception de la fourche isochrone --hypothèse finalement très faible. Ainsi, une variation de la tension se traduit par une réduction de la vitesse de fonctionnement sans pour autant altérer la fonctionnalité du circuit. Cette thèse étudie la robustesse des circuits asynchrones dans des environnements de fonctionnement très sévères susceptibles de mettre en défaut la correction fonctionnelle des circuits asynchrones QDI. Cette situation se présente par exemple quand les transitions des signaux sur les portes deviennent très lentes. Cette situation exceptionnelle peut-être directement provoquée par un environnement agressif (émission électromagnétique, particules à haute énergie, ...) ou par les effets du vieillissement du circuit intégré. Dans un contexte où le circuit est employé à des fins sécuritaires telles que les applications aéronautiques, spatiales ou médicales, il s'avère nécessaire de quantifier les limites de fonctionnement des circuits asynchrones et de trouver des moyens pour améliorer leur robustesse. Ce manuscrit propose une étude complète du comportement des circuits asynchrones et propose des techniques de conception pour en améliorer la robustesse. Les résultats obtenus ont été validés sur des technologies CMOS avancées de ST Microelectronics par des simulations analogiques d'une part, et avec l'aide d'un outil de preuve formelle développé à l'Université British Columbia au Canada d'autre part. / The design of self-timed integrated circuits, including QDI (Quasi-Delay Insensitive) circuits, lead to robust circuits against variabilities in manufacturing processes and in running conditions (voltage, temperature). These qualities are consequences of the synthesys flow that does not create timing assumptions excepted a weak one related to isochronic forks. In self-timed circuits, the running speed automatically adjusts to the available supply voltage with no behavioral changes. This work focuses on the self-timed circuit robustness in the context of environments where running conditions can make QDI self-timed circuits failing. For instance, this happens when transition speeds at gate entrances become very slow. This uncommonly encountered situation can be triggered in harsh environments (with electromagnetic disturbences, high-energy particulesdots) or because of age effects on manufactured chips. If the integrated circuit is designed for critical operations such as in aeronautical, spatial or medical applications, the self-timed circuit limits have to be carrefully evaluated and eventually shifted in order to improve the circuit robustness. This publication includes a complete study of the self-timed circuit behaviors and some design proposals in order to enhance the circuit robustness. Experimental results were obtained firstly, during analog simulations targetting advanced CMOS technologies from STMicroelectronics and secondly, using formal methods implemented in a tool from the University of British Columbia.
236

Robustesse par conception de circuits implantés sur FPGA SRAM et validation par injection de fautes / Robustness improvement by designing circuits implemented on SRAM FPGAs and validation by fault injection

Ben Jirad, Mohamed 01 July 2013 (has links)
Cette thèse s'intéresse en premier lieu à l'évaluation des effets fonctionnels des erreurs survenant dans la mémoire SRAM de configuration de certains FPGAs. La famille Virtex II Pro de Xilinx est utilisée comme premier cas pratique d'expérimentation. Des expérimentations sous faisceau laser nous ont permis d'avoir une bonne vue d'ensemble sur les motifs d'erreurs réalistes qui sont obtenus par des sources de perturbations réelles. Une méthodologie adaptée d'injection de fautes a donc été définie pour permettre une meilleure évaluation, en phase de conception, de la robustesse d'un circuit implanté sur ce type de technologie. Cette méthodologie est basée sur de la reconfiguration dynamique. Le même type d'approche a ensuite été évalué sur plusieurs cibles technologiques, ce qui a nécessité le développement de plusieurs environnements d'injection de fautes. L'étude a pour la première fois inclus la famille AT40K de ATMEL, qui permet un type de reconfiguration unique et efficace. Le second type de contribution concerne l'augmentation à faible coût de la robustesse de circuits implantés sur des plateformes FPGA SRAM. Nous proposons une approche de protection sélective exploitant les ressources du FPGA inutilisées par l'application. L'approche a été automatisée sur plusieurs cibles technologiques (Xilinx, Altera) et l'efficacité est analysée en utilisant les méthodes d'injection de fautes précédemment développées. / This thesis focuses primarily on the evaluation of the functional effects of errors occurring in the SRAM configuration memory of some FPGAs. Xilinx Virtex II Pro family is used as a first case study. Experiments under laser beam allowed us to have a good overview of realistic error patterns, related to real disturbance sources. A suited fault injection methodology has thus been defined to improve design-time robustness evaluations of a circuit implemented on this type of technology. This methodology is based on runtime reconfiguration. The approach has then been evaluated on several technological targets, requiring the development of several fault injection environments. The study included for the first time the ATMEL AT40K family, with a unique and efficient reconfiguration mode. The second type of contribution is focused on the improvement at low cost of the robustness of designs implemented on SRAM-based FPGA platforms. We propose a selective protection approach exploiting resources unused by the application. The approach has been automated on several technological targets (Xilinx, Altera) and the efficiency has been analyzed by taking advantage of the fault injection techniques previously developed.
237

Vers des protocoles de tolérance aux fautes Byzantines efficaces et robustes / Efficient and Robust Byzantine Fault Tolerant Replication Protocols

Aublin, Pierre-Louis 21 January 2014 (has links)
Les systèmes d'information deviennent de plus en plus complexes et il est difficile de les garantir exempts de fautes. La réplication de machines à états est une technique permettant de tolérer les fautes, quelque soit leur nature, qu'elles soient logicielles ou matérielles. Cette thèse traite des protocoles de réplication de machines à états tolérant les fautes arbitraires, également appelées Byzantines. Ces protocoles doivent relever deux défis : (i) ils doivent être efficaces, c'est-à-dire que leurs performances doivent être les meilleurs possibles, afin de masquer le coût supplémentaire dû à la réplication et (ii) ils doivent être robustes, c'est-à-dire qu'une attaque ne doit pas faire baisser leurs performances de manière importante. Dans cette thèse nous observons qu'aucun protocole ne relève ces deux défis en même temps : les protocoles que nous connaissons aujourd'hui sont soit conçus pour être efficaces au détriment de leur robustesse, soit conçus pour être robustes au détriment de leurs performances. Une première contribution de cette thèse est la conception d'un nouveau protocole qui réunit le meilleur des deux mondes. Ce protocole, R-Aliph, combine un protocole efficace mais peu robuste avec un protocole robuste afin de fournir un protocole à la fois efficace et robuste. Nous évaluons ce protocole de manière expérimentale et montrons que ses performances en cas d'attaque sont égales aux performances du protocole robuste sous-jacent. De plus, ses performances dans le cas sans faute sont très proches des performances du protocole connu le plus efficace : la différence maximale de débit est inférieure à 6%. Dans la seconde partie de cette thèse nous observons que les protocoles conçus pour être robustes sont peu robustes en réalité. En effet, il est possible de concevoir une attaque dans laquelle leur perte de débit est supérieure à 78%. Nous identifions le problème de ces protocoles et nous concevons un nouveau protocole plus robuste que les précédents : RBFT. L'idée de base de ce protocole est d'exécuter en parallèle plusieurs instances d'un même protocole. Les performances de ces différentes instances sont surveillées de près afin de détecter tout comportement malicieux. Nous évaluons RBFT dans le cas sans faute et en cas d'attaque. Nous montrons que ses performances dans le cas sans faute sont comparables aux performances des protocoles considérés comme robustes. De plus, nous observons que la dégradation maximale de performance qu'un attaquant peut causer sur le système est inférieure à 3%, même dans le cas de la pire attaque possible. / Information systems become more and more complex and it is difficult to guarantee that they are bug-free. State Machine Replication is a technique for tolerating faults, regardless their nature, whether they are software or hardware faults. This thesis studies Fault Tolerant State Machine Replication protocols that tolerate arbitrary, also called Byzantine, faults. These protocols face two challenges: (i) they must be efficient, i.e., their performance have to be the best ones, in order to mask the cost of the replication and (ii) they must be robust, i.e., an attack should not cause an important performance degradation. In this thesis, we observe that no protocol addresses both of these challenges: current protocols are either designed to be efficient but fail to be robust, or designed to be robust but exhibit poor performance. A first contribution of this thesis is the design of a new protocol which achieves the best of both worlds. This protocol, R-Aliph, combines an efficient but not robust protocol with a protocol designed to be robust. The result is a protocol that is both robust and efficient. We evaluate this protocol experimentally and show that its performance under attack equals the performance of the underlying robust protocol. Moreover, its performance in the fault-free case is close to the performance of the best known efficient protocol: the maximal throughput difference is less than 6%. In the second part of this thesis we analyze the state-of-the-art robust protocols and demonstrate that they are not effectively robust. Indeed, one can run an attack on each of these protocols such that the throughput loss is at least equal to 78%. We identify the problem of these protocols and design a new, effectively robust, protocol called RBFT. The main idea of this protocol is to execute several instances of a robust protocol in parallel and closely monitor their performance, in order to detect a malicious behaviour. We evaluate RBFT in the fault-free case and under attack. We observe that its performance in the fault-free case is equivalent to the performance of the other so-called robust BFT protocols. Moreover, we show that the maximal throughput degradation, under the worst possible attack, is less than 3%.
238

Contribution à l'optimisation en conception préliminaire de produit / Contribution to optimization in product's preliminary design

Mazhoud, Issam 07 May 2014 (has links)
L'optimisation en conception de produit constitue une activité à forte valeur ajoutée en entreprise. Ceci est d'autant plus important qu'elle est appliquée dans les premières phases du processus de conception. Les travaux dans cette thèse se placent dans ce contexte et proposent des outils adaptés d'aide à la décision en pré-dimensionnement de produits suivant deux critères: présence ou non de fonctionnelles dans le modèle, prise en compte ou non des incertitudes dans le modèle. Une méthode à base de calcul d'intervalles et de propagation de contraintes qui permet de faire de l'optimisation déterministe est introduite. Cette méthode permet de traiter les modèles d'optimisation sans fonctionnelles et sans prise en compte d'incertitudes. Une reformulation qui permet d'améliorer la convergence de l'algorithme est introduite. Une méthode d'optimisation stochastique à base d'essaims particulaires est présentée pour traiter les modèles de plus grande dimension. Un nouveau mécanisme de gestion de contraintes est introduit. Cet algorithme a aussi été étendu pour traiter les problèmes de conception en présence de contraintes du type équations différentielles. Afin de traiter les incertitudes dans les modèles, une méthode d'optimisation robuste est présentée. Elle combine un algorithme d'optimisation stochastique avec une méthode de propagation d'incertitude (PoV). Cette méthode de propagation d'incertitude est étendu aux modèles incluant des fonctionnelles. / The optimization in product design is a high added-value activity. This is all the more important when it is performed at the early stages of the design process. The work presented in this thesis is placed in this context. It proposes adapted decision making tools in preliminary design following two criteria: whether or not the model contains functionals, and whether it takes into considerations the uncertainties. A method based on interval arithmetic and constraint propagation allowing to perform deterministic global optimization is introduced. This method allows handling optimization models without functionals and without considering uncertainties. A reformulation that permits to improve the algorithm convergence is introduced. A stochastic optimization method based on particular swarms is introduced in order to handle higher dimensional problems. A new constraint handling mechanism is introduced and tested on engineering problems. This algorithm has also been extended to design problems with ordinary differential equations constraints. In order to consider uncertainties, a robust optimization method is introduced. It combines a stochastic optimization method with an uncertainty propagation method called PoV. An extension of PoV to models involving functionals is introduced.
239

Estrutura das interações abelhas-plantas: uso de plantas-iscas e análises polínicas para a determinação do nicho alimentar e descrição das redes ecológicas em sistemas naturais e cultivados / Structure of bee-plant interactions: the use of plant-baits and pollen analyzis to determine the food niche and description of ecological networks in natural and crop systems

Rabelo, Laíce Souza 17 February 2016 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The food niche and the interactions between different groups of bees and plants can be studied, in dissimilar systems, using the association of tools, such as plant-bait, pollen analysis and interaction network approach. In this context, the general aim of this work was to study the interactions between bees and plants in two ecological systems: one natural, using species of Malpighiaceae as plant-baits, and other crop area, using the consortium between eggplant (Solanum melongena) and pumpkin (Cucurbita moschata) as bait plants. In the natural system, observations of the foraging behaviour and the analysis of pollen loads of oil-collecting bees sampled in Byrsonima spp. showed that: 1) the behaviour of foraging for pollen and oil was significantly associated with the taxonomic groups; 2) the main pollen source for these bees was Byrsonima spp. and 3) the robustness of interaction networks was influenced by the removal of bees according to the abundance, body size and taxonomic groups. Additionally, in this system we also studied the food niche of Exomalopsis fulvofasciata. This species foraged in five floral sources (being Byrsonima the most important) and used predominantly small pollen grains and flowers with non poricidal anthers. In the agrosystem, we observed a low similarity in the communities of flower visitors between the two crops that have been exploited for the collection of complementary resources (pollen and nectar). Furthermore, we observed that the complete system, formed by all bee species, both crops and surrounding plants, showed a greater robustness to the removal of species than all the simplest scenarios, except for the exclusion of bees according to their abundance. Thus, the results obtained in this study contributed to a greater understanding of bees-plants interactions in natural areas in Cerrado and crop areas. Information about the foraging behaviour and food niche, associated with simulations of possible extinction scenarios can be used to support actions of conservation and management of pollinators. / O nicho alimentar e as interações entre diferentes grupos de abelhas e plantas podem ser estudados, em sistemas distintos, usando a associação de ferramentas, como planta-isca, análise polínica e abordagem de redes de interações. Nesse contexto, o objetivo geral deste trabalho foi estudar as interações entre abelhas e plantas em dois sistemas ecológicos: um natural, utilizando espécies de Malpighiaceae como plantas-iscas, e outro cultivado, utilizando-se consórcio de cultivos de abóbora-menina (Cucurbita moschata) e berinjela (Solanum melongena) como plantas-iscas. No sistema natural, a observação do comportamento de forrageamento e a análise das cargas polínicas das abelhas coletoras de óleo amostradas em Byrsonima spp. mostraram que: 1) os comportamentos de forrageamentos para pólen e óleo foram significativamente associados aos grupos taxonômicos; 2) a principal fonte de pólen para esses insetos foi Byrsonima spp. e 3) a robustez das redes de interações foi influenciada pela remoção das abelhas de acordo com a abundância, tamanho corporal e grupos taxonômicos. Além disso, nesse sistema também foi estudado o nicho alimentar de Exomalopsis fulvofasciata (Apidae). Essa espécie forrageou em cinco fontes florais (sendo Byrsonima a principal delas) e usou predominantemente grãos de pólen pequenos e flores com anteras não poricidas. Já no agrossistema, foi verificada uma baixa similaridade entre as comunidades de visitantes florais dos cultivos que foram explorados para a coleta de recursos complementares (pólen e néctar). Além disso, observou-se que o sistema completo, formado por todas as espécies de abelhas, ambos os cultivos e as plantas do entorno, apresentou maior robustez quanto à remoção de espécies do que todos os cenários mais simples, exceto quanto a eliminação das abelhas de acordo com a abundância. Assim, os resultados obtidos contribuiram com o Bmaior entendimento das interações abelhas-plantas em reservas naturais de Cerrado e áreas cultivadas. As informações sobre os comportamentos de forrageamento e o nicho alimentar, associada às simulações de possíveis cenários de extinções, podem ser usadas como subsídio para ações de conservação e manejo dos polinizadores. / Doutor em Ecologia e Conservação de Recursos Naturais
240

Método de ajuste para MPC baseado em multi-cenários para sistemas não quadrados

Santos, José Eduardo Weber dos January 2016 (has links)
A utilização de controladores preditivos multivariáveis na indústria de processos cresceu significativamente nos últimos anos principalmente devido à versatilidade e a confiabilidade que essa ferramenta proporciona em termos de controle avançado. No entanto, aspectos relacionados à aplicação prática do que vem sendo desenvolvido no meio acadêmico possui pouca difusão na indústria devido às configurações clássicas adotadas, como sistemas quadrados (com o mesmo número de variáveis controladas e manipuladas), modelos lineares, utilização de setpoint e etc. diferindo daquilo que está disponível e é amplamente utilizado industrialmente: sistemas não-quadrados (geralmente com mais variáveis controladas do que manipuladas), modelos não-lineares e utilização de soft-constraints. Esse trabalho propõe uma metodologia para ajuste dos parâmetros presentes em um controlador preditivo, atento à variedade de algoritmos presentes na indústria de processos. Essa metodologia se baseia na obtenção do melhor desempenho alcançável para cada cenário de um modelo global do processo, atendendo as restrições de Número de Desempenho Robusto relativo (rRPN), Máxima Sensibilidade e restrições nas ações de controle. Baseado em um desempenho que é alcançável, o modelo linear global é escalonado (assim como a planta não-linear) e os pesos que levam o sistema para a melhor condição operacional são estimados. Essa técnica abrange controladores operando em faixas e/ou setpoint e configurações não-quadradas, i.e., com mais variáveis controladas do que manipuladas. A abordagem proposta foi testada em uma planta de quatro tanques esféricos com aquecimento apresentando resultados coerentes, corroborando seu potencial de aplicação industrial. / Due to their versatility and reliability, Model Predictive Controllers (MPCs) are the standard solution for advanced process control in the process industry. However, there is a gap between the academic developments and the actual industrial applications, since the most academic studies focus on systems working with set-points and same number of manipulated and controlled variables, whereas the industrial application cope with non-squared configuration usually with several controlled variables in ranging and a reduced number of manipulated variables. This work proposes a tuning methodology for the countable parameters presents in a typical industrial predictive controller, considering the variety of the algorithms presents commercially in the process industry. This methodology is based on the estimation of the best attainable performance for each scenario of the global model of the process, constrained by the relative Robust Performance Number (rRPN), Maximal Sensitivity and restrictions in the control actions. Based on a performance that is attainable, the linear global model is scaled (and the non-linear) and the weights that lead the system to the best operational condition are estimated. This technique covers controllers operating in zones of control and/or set-point tracking and non-square configurations, i.e., with more controlled variables than manipulated. The proposed approach was tested in a Quadruple-Spherical tanks heating system presenting coherent results indicating its potential for industrial applications.

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