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1

Xing, Huajing. "Impact of thiamine and pyridoxine on alcoholic fermentations of synthetic grape juice". Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Summer2007/h_xing_072607.pdf.

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2

Saxton, Valerie Patricia. "Influence of ripening grape compounds on behavioural responses of birds". Phd thesis, Lincoln University. Agriculture and Life Sciences Division, 2004. http://theses.lincoln.ac.nz/public/adt-NZLIU20061207.121738/.

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Vineyards in New Zealand suffer bird damage caused by several avian species, including blackbirds and silvereyes. The introduced European Blackbird takes whole grapes which reduces yield. The self-introduced Australasian Silvereye pecks on grapes, leaving them on the vine to be further attacked by fungi and bacteria, and the subsequent off-odours can cause grapes to be refused by the winery or to suffer a price-reduction. Bird control methods remain primitive and largely ineffective during the long ripening period of wine grapes. An ecologically sound method to manage and reduce bird pressure requires deeper understanding of why some birds eat grapes, especially since grapes are not particularly nutritious. This work investigated the extent to which blackbirds and silvereyes are attracted by various compounds in ripening grapes. Since in natural grapes these compounds develop and change simultaneously, I developed an artificial grape in which a single parameter could be investigated. Artificial grapes (and sometimes nectar) were presented on a bird feeder table and the responses of birds to hexose sugars, the aromas 2-3-isobutylmethoxypyrazine and geraniol, tartaric and malic acids, grape tannins, and purple and green colour were recorded on timelapse video and analysed.
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3

Saxton, V. P. "Influence of ripening grape compounds on behavioural responses of birds". Diss., Lincoln University, 2004. http://hdl.handle.net/10182/28.

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Vineyards in New Zealand suffer bird damage caused by several avian species, including blackbirds and silvereyes. The introduced European Blackbird takes whole grapes which reduces yield. The self-introduced Australasian Silvereye pecks on grapes, leaving them on the vine to be further attacked by fungi and bacteria, and the subsequent off-odours can cause grapes to be refused by the winery or to suffer a price-reduction. Bird control methods remain primitive and largely ineffective during the long ripening period of wine grapes. An ecologically sound method to manage and reduce bird pressure requires deeper understanding of why some birds eat grapes, especially since grapes are not particularly nutritious. This work investigated the extent to which blackbirds and silvereyes are attracted by various compounds in ripening grapes. Since in natural grapes these compounds develop and change simultaneously, I developed an artificial grape in which a single parameter could be investigated. Artificial grapes (and sometimes nectar) were presented on a bird feeder table and the responses of birds to hexose sugars, the aromas 2-3-isobutylmethoxypyrazine and geraniol, tartaric and malic acids, grape tannins, and purple and green colour were recorded on timelapse video and analysed.
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4

Yildiz, Ali. "Resource-aware Load Balancing System With Artificial Neural Networks". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607613/index.pdf.

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As the distributed systems becomes popular, efficient load balancing systems taking better decisions must be designed. The most important reasons that necessitate load balancing in a distributed system are the heterogeneous hosts having different com- puting powers, external loads and the tasks running on different hosts but communi- cating with each other. In this thesis, a load balancing approach, called RALBANN, developed using graph partitioning and artificial neural networks (ANNs) is de- scribed. The aim of RALBANN is to integrate the successful load balancing deci- sions of graph partitioning algorithms with the efficient decision making mechanism of ANNs. The results showed that using ANNs to make efficient load balancing can be very beneficial. If trained enough, ANNs may load the balance as good as graph partitioning algorithms more efficiently.
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5

Chang, Kaiwen. "Apprentissage artificiel pour la segmentation d'image". Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEM058.

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La présente thèse vise à développer une méthodologie générale basée sur des méthodes d’apprentissage pour effectuer la segmentation d’une base de données constituée d’images similaires, à partir d’un nombre limité d’exemples d’entraînement. Cette méthodologie est destinée à être appliquée à des images recueillies dans le cadre d’observations de la terre ou lors d’expériences menées en science des matériaux, pour lesquelles il n’y a pas suffisamment d’exemples d’entraînement pour appliquer des méthodes basées sur des techniques d’apprentissage profond. La méthodologie proposée commence par construire une partition de l’image en superpixels, avant de fusionner progressivement les différents superpixels obtenus jusqu’à l’obtention d’une segmentation valide. Les deux principales contributions de cette thèse sont le développement d’un nouvel algorithme de superpixel basé sur l’équation eikonale, et le développement d’un algorithme de fusion de superpixels basé sur une adaptation de l’équation eikonale au contexte des graphes. L’algorithme de fusion des superpixels s’appuie sur un graphe d’adjacence construit à partir de la partition en superpixels. Les arêtes de ce graphe sont valuées par une mesure de dissimilarité prédite par un algorithme d’apprentissage à partir des caractéristiques de bas niveau calculées sur les superpixels. A titre d’application, l’approche de segmentation est évaluée sur la base de données SWIMSEG, qui contient des images de nuages. Pour cette base de données, avec un nombre limité d’images d’entraînement, nous obtenons des résultats de segmentation similaires à ceux de l’état de l’art
In this PhD thesis, our aim is to establish a general methodology for performing the segmentation of a dataset constituted of similar images with only a few annotated images as training examples. This methodology is directly intended to be applied to images gathered in Earth observation or materials science applications, for which there is not enough annotated examples to train state-of-the-art deep learning based segmentation algorithms. The proposed methodology starts from a superpixel partition of the image and gradually merges the initial regions until anactual segmentation is obtained. The two main contributions described in this PhD thesis are the development of a new superpixel algorithm which makes use of the Eikonal equation, and the development of a superpixel merging algorithm steaming from the adaption of the Eikonal equation to the setting of graphs. The superpixels merging approach makes use of a region adjacency graph computed from the superpixel partition. The edges are weighted by a dissimilarity measure learned by a machine learning algorithm from low-level cues computed on the superpixels. In terms of application, our approach to image segmentation is finally evaluated on the SWIMSEG dataset, a dataset which contains sky cloud images. On this dataset, using only a limited amount of images for training our algorithm, we were able to obtain segmentation results similar to the ones obtained with state-of-the-art algorithms
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6

Filho, Flavio Guilherme Vaz de Almeida. "Variação temporal do campo gravitacional detectada pelo satélite GRACE: aplicação na bacia Amazônica". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-10112009-094808/.

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O objetivo deste trabalho é investigar o processo das variações do campo gravitacional, obtidas através da missão espacial GRACE e seu relacionamento com a dinâmica das águas na região Amazônica. A partir disto, procurou-se desenvolver uma metodologia para as estimativas das cotas dágua em áreas inundáveis não monitoradas ou de difícil acesso. Para isso, os coeficientes de Stokes, disponibilizados pelo GRGS de Toulouse, foram convertidos, por um processo denominado inversão, no equivalente à altura dágua (EqW) para o período de aproximadamente 4 anos (julho de 2002 a maio de 2006) e os valores comparados às cotas do nível dágua in-situ obtidas pela Agência Nacional de Águas (ANA). A escolha da bacia Amazônica está relacionada ao fato da mesma apresentar, próximo ao centro, amplitudes de aproximadamente 1250 mm no nível do EqW, sendo as maiores do mundo. A regionalização dos modelos globais das variações deste campo pôde ser aplicada para uma boa estimativa nas cotas dágua in-situ. Assim, foram estimados os erros desta metodologia, que são da ordem de ~160 mm para o EqW, oriundos dos erros nos coeficientes de Stokes, truncamento do espectro e erros de vazamento de informações hidrológicas das bacias vizinhas. Esta metodologia trata, portanto, de estimar as cotas onde não existam estações de monitoramento, avaliando a ordem de grandeza dos erros. Por fim, são apresentadas cartas que relacionam hidrogeologicamente as defasagens apresentadas nos ciclos semi-anuais e as áreas onde a metodologia poderá ser melhor aplicada com estimativas mais precisas do EqW e com maior coerência entre os dados satelitais e terrestres.
A comparison between vertically-integrated equivalent water height (EWH) derived from GRACE gravity anomalies with in situ water level time series measured at ground-based hydrometric stations (HS) in the Amazon basin is figure out in the thesis. A methodology for EWH estimation at ungauged sites is presented. The Stokes coefficients disponibilized by GRGS - Toulouse at a 10-day interval were converted into EWH for a ~4-year period (July-2002 to May-2006) using the methodology so-called inversion, and then compared to HS level. In the basin, the amplitudes of EWH signal are the largest on the Earth and can reach on the order of 1250 mm at the center of the basin (e.g. Manaus station). The uncertainties represent ~160 mm of EWH, including Stokes coefficient uncertainties, leakage errors and spectrum truncation. A methodology for acquire water level historical series at ungauged places is proposed with the estimated incertitude. A hydrological map is compared with a correlation chart and figure out areas where this methodology works better, in addition, compared also with shift phased semi-annual cycles.
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7

Zhang, Jiaxin. "Power-law Graph Cuts". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1418749967.

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8

Kothari, Bhavin Chandrakant. "Structural optimisation of artificial neural networks by the genetic algorithm using a new encoding scheme". Thesis, Brunel University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389263.

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9

Lima, Fernando Correa. "\"Um resolvedor SAT paralelo com BSP sobre uma grade\"". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-03062007-144527/.

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O Objetivo deste trabalho foi implementar um resolvedor distribuído para o problema de satisfabilidade em lógica proposicional (SAT) que pudesse ser executado em uma grade de computadores. Foi analisada a influência que o número de máquinas utilizadas pela grade para resolver diversas instâncias do SAT exerce sobre o desempenho do resolvedor implementado
O Objetivo deste trabalho foi implementar um resolvedor distribuído para o problema de satisfabilidade em lógica proposicional (SAT) que pudesse ser executado em uma grade de computadores. Foi analisada a influência que o número de máquinas utilizadas pela grade para resolver diversas instâncias do SAT exerce sobre o desempenho do resolvedor implementado
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10

Garcia, Edward T. "Multi-Agent Narrative Experience Management as Story Graph Pruning". ScholarWorks@UNO, 2019. https://scholarworks.uno.edu/td/2694.

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In this thesis I describe a method where an experience manager chooses actions for non-player characters (NPCs) in intelligent interactive narratives through story graph representation and pruning. The space of all stories can be represented as a story graph where nodes are states and edges are actions. By shaping the domain as a story graph, experience manager decisions can be made by pruning edges. Starting with a full graph, I apply a set of pruning strategies that will allow the narrative to be finishable, NPCs to act believably, and the player to be responsible for how the story unfolds. By never pruning player actions, the experience manager can accommodate any player choice. This experience management technique was first implemented on a training simulation, where participants’ performance improved over repeated sessions. This technique was also employed on an adventure game where players generally found the NPCs’ behaviors to be more believable than the control.
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11

Shaikh, Amir. "Artificial neural network optimisation using configuration invariant graph syntax and genetic algorithms". Thesis, Brunel University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412429.

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12

Sales, Raquel Pinto. "Influências do esforço muscular respiratório e da assincronia paciente-ventilador sobre o “stress” e o “strain” pulmonares em modelo mecânico de síndrome da angústia respiratória aguda". reponame:Repositório Institucional da UFC, 2014. http://www.repositorio.ufc.br/handle/riufc/9387.

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SALES, Raquel Pinto. Influências do esforço muscular respiratório e da assincronia paciente-ventilador sobre o “stress” e o “strain” pulmonares em modelo mecânico de síndrome da angústia respiratória aguda. 2014. 59 f. Dissertação (Mestrado em Ciências Médicas) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2014.
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Acute Respiratory Distress Syndrome (ARDS) is an inflammatory disease characterized by pulmonary edema, stiff lungs and hypoxemia. Patients with ARDS are more susceptible to VILI (ventilator induced lung injury). Under mechanical ventilation, lung stress and strain are the main determinants of VILI and in patients with muscle effort patient-ventilator asynchrony may enhance this phenomenon. Ventilation modes PCV and VCV with auto-flow can minimize patient-ventilator asynchrony, but then can liberate the offer of flow and tidal volume, compromising the protective ventilatory strategy in ARDS. This study aimed to evaluate the influence of muscle effort and patient-ventilator asynchrony on pulmonary stress and strain in a mechanic lung model of acute respiratory distress syndrome. An experimental bench study was performed, using a lung simulator, ASL 5000TM, in which was configured a lung model with restrictive respiratory mechanics with complacency of 25ml/cmH2O and resistance of 10 cmH2O/L/sec. Muscle effort was adjusted in three situations: no muscular effort (Pmus = 0), with inspiratory muscle effort (Pmus = -5 cmH2O) and inspiratory and expiratory effort (Pmus = -5/+5 cmH2O), all with breathe rate (b) of 20 bpm. Five ventilators were connected to the simulator through and endotracheal tube No 8.0 mm and adjusted on VCV, VCV with Auto-flowTM (in the ventilator in which it was available) and PCV modes, all with tidal volume (VT): 420 ml, PEEP: 10 cmH2O and breath rate set in two situations: b = 15 bpm (lower than b of the respiratory muscle effort) and b = 25 bpm (higher than b of the respiratory muscle effort). Variables analyzed were: maximum VT, alveolar pressure at the end of inspiration, effective PEEP, driving pressure, transpulmonary pressure at the end of inspiration and expiration, average transpulmonary pressure, inspiratory peak flow and analysis of mechanic curves. In the studied lung model the b of the ventilator adjusted higher of the b of the patient and not the muscle effort was the main determinant for the development of patient-ventilator asynchrony, causing large variations of the VT and pulmonary pressures, intensifying the lung stress and strain. The ventilatory modes had similar behavior, although VCV Auto-flowTM and PCV have presented slightly higher values of VT and pulmonary pressures. Thus it is concluded that the proper adjustment of the programed breath rate in the assisted/controlled modes can minimize patient-ventilator asynchrony, reducing lung stress and strain.
A Síndrome da Angústia Respiratória Aguda (SARA) é uma doença inflamatória caracterizada por edema pulmonar, pulmões rígidos e hipoxemia. Pacientes com SARA estão mais suscetíveis à VILI (ventilator induced lung injury). Sob ventilação mecânica, o stress e o strain pulmonares são os principais determinantes da VILI e nos pacientes com esforço muscular a assincronia paciente-ventilador pode potencializar este fenômeno. Os modos ventilatórios PCV e VCV com AutoFlow® podem minimizar a assincronia paciente-ventilador, mas por outro lado podem liberar a oferta de fluxo e volume corrente, comprometendo a estratégia ventilatória protetora na SARA. Objetivou-se avaliar as influências do esforço muscular e da assincronia paciente-ventilador sobre o “strain” e o “stress” pulmonares em modelo pulmonar mecânico de síndrome da angústia respiratória aguda. Foi realizado um estudo experimental de bancada, utilizando um simulador de pulmão, ASL 5000® no qual foi configurado um modelo pulmonar com mecânica respiratória restritiva, com complacência de 25ml/cmH2O e resistência de 10 cmH2O/L/sec. O esforço muscular foi ajustado em três situações: sem esforço muscular (Pmus=0), com esforço muscular inspiratório (Pmus= -5cmH2O) e esforço inspiratório e expiratório (Pmus= -5/+5 cmH2O), todos com frequência respiratória (f) de 20rpm. Ao simulador foram conectados cinco ventiladores através de um tubo orotraqueal nº 8,0 mm e ajustados nos modos VCV, VCV com sistema AutoFlow® (no ventilador que tinha o sistema disponível) e PCV, todos com volume corrente (VC): 420 ml, PEEP: 10 cmH2O e frequência respiratória programada em duas situações: f=15rpm (< que a f de esforço muscular respiratório) e f=25rpm (> que a f de esforço muscular respiratório). As variáveis analisadas foram: VC máximo, a pressão alveolar no final da inspiração, PEEP efetiva, driving pressure, pressão transpulmonar no final da inspiração e expiração, pressão transpulmonar média, pico de fluxo inspiratório e análise das curvas de mecânica. No modelo pulmonar estudado a f do ventilador pulmonar ajustada acima da f do paciente e não o esforço muscular o principal determinante para o desenvolvimento de assincronia paciente ventilador, causando grandes variações de VC e pressões pulmonares, o que intensificou o stress e strain pulmonares. Os modos ventilatórios tiveram comportamento semelhante, embora os modos VCV AutoFlow® e PCV tenham apresentado valores discretamente maiores de VC e pressões pulmonares. Desta forma conclui-se que o ajuste adequado da frequência programada nos modos assistido/controlado podem pode minimizar a assincronia paciente ventilador reduzindo o stress e strain pulmonares. Palavras-
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13

Goodman, Genghis. "A Machine Learning Approach to Artificial Floorplan Generation". UKnowledge, 2019. https://uknowledge.uky.edu/cs_etds/89.

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The process of designing a floorplan is highly iterative and requires extensive human labor. Currently, there are a number of computer programs that aid humans in floorplan design. These programs, however, are limited in their inability to fully automate the creative process. Such automation would allow a professional to quickly generate many possible floorplan solutions, greatly expediting the process. However, automating this creative process is very difficult because of the many implicit and explicit rules a model must learn in order create viable floorplans. In this paper, we propose a method of floorplan generation using two machine learning models: a sequential model that generates rooms within the floorplan, and a graph-based model that finds adjacencies between generated rooms. Each of these models can be altered such that they are each capable of producing a floorplan independently; however, we find that the combination of these models outperforms each of its pieces, as well as a statistic-based approach.
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14

Kapageridis, Ioannis K. "Application of artificial neural network systems to ore grade estimation from exploration data". Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301663.

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15

Yekollu, Srikar. "Graph Based Regularization of Large Covariance Matrices". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1237243768.

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Lele, Omkar M. "Building a Computational Model for Graph Comprehension Using BiSoar". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243999359.

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17

Ferroni, Nicola. "Exact Combinatorial Optimization with Graph Convolutional Neural Networks". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17502/.

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Combinatorial optimization problems are typically tackled by the branch-and-bound paradigm. We propose to learn a variable selection policy for branch-and-bound in mixed-integer linear programming, by imitation learning on a diversified variant of the strong branching expert rule. We encode states as bipartite graphs and parameterize the policy as a graph convolutional neural network. Experiments on a series of synthetic problems demonstrate that our approach produces policies that can improve upon expert-designed branching rules on large problems, and generalize to instances significantly larger than seen during training.
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Cori, Marcel. "Modèles pour la représentation et l'interrogation de données textuelles et de connaissances". Paris 7, 1987. http://www.theses.fr/1987PA077047.

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Ces modèles combinent à des réseaux sémantiques des bases de connaissances formées de règles. Les données sont représentées par des graphes sans circuit, ordonnés ou semi-ordonnés, ainsi que par des grammaires de graphes. La recherche de la réponse à une question se ramène à la recherche de morphismes entre structures. Les réprésentations sont construites automatiquement par l'appel à des règles de réécriture de graphes
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Nunes, Anderson Afonso. "Restringindo o espaço de busca na geração de estruturas de coalizão utilizando grafos". Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1412.

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O problema de geração de estruturas de coalizão (CSG) envolve o particionamento do conjunto de agentes em todos os subconjuntos(ou, coalizões) possíveis. O que torna esse problema desafiador é o número de coalizões possíveis crescer exponencialmente a medida que novos agentes são inseridos, o número de coalizões é (2n − 1) onde n é o número de agentes. Entretanto, em muitas aplicações do mundo real, existem limitações inerentes nas coalizões possíveis: por exemplo, determinados agentes podem ser proibidos de estar na mesma coalizão, ou a estrutura de coalizão pode ser obrigada a conter coalizões do mesmo tamanho. Quando consideramos CSG restrito por grafos, onde a viabilidade de uma coalizão é restrita por um grafo de sinergia dos agentes, a complexidade computacional pode ser a mesma ou menor, dependendo do que se considera uma coalizão válida. Os grafos de sinergia são representações dos agentes como sendo os vértices e as suas relações são as arestas. Este trabalho é um estudo sobre a utilização de restrições envolvendo grafos como uma heurística sobre as coalizões para o problema enumeração de coalizão, de forma a considerar uma coalizão factível ou não de acordo com a densidade do subgrafo induzido pelos agentes. Os trabalhos atuais, que utilizam os grafos de restrição como heurística para reduzir a complexidade computacional, consideram uma coalizão válida somente se o subgrafo formado pelos agentes da coalizão é conexo. Verificou-se experimentalmente para grafos com a propriedade power law, comum em uma variedade de grafos reais, que restringir uma coalizão válida como sendo um subgrafo conexo pode não ser uma redução significativa. Entretanto a utilização de um subgrafo com restrições mais fortes, em particular uma clique garante uma redução exponencial do número de coalizões consideradas. Não existem teoremas que possam calcular qual a quantidade de subgrafos conexos ou mesmo o número de cliques em um grafo do tipo power law. No presente trabalho foi possível calcular experimentalmente para grafos power law com ate 17 vértices, sendo que também são apresentados resultados analíticos para grafos estrela (Kn−1,1 ). Os grafos estrela são uma aproximação aceitável, pois formam um hub, estrutura característica de grafos power law. Como trabalhos futuros podem ser citados: o mapeamento de domínios para os quais a restrição de clique seria adequada, além do desenvolvimento de um algoritmo que incorpore a restrição diretamente na contagem de coalizões validas.
The coalition structures generating problem (CSG) involves partitioning the set of agents in all possible subsets (or coalitions). What makes this problem challenging is the number of possible coalitions that grows exponentially as new agents are inserted. The number of coalitions is (2n − 1) where n is the number of agents. However, in many real-world applications, there are inherent limitations on possible coalitions: for example, some individuals may be prohibited from being in the same coalition or coalition structure may be required to contain coalitions of the same size. When we consider CSG restricted by graphs where the viability of a coalition is restricted by a synergy graph, the computational complexity can be maintained or eventually be smaller depending on what is considered a valid coalition. Synergy graphs are representations of the agents as being the vertices and their relationships are the edges. This work is a study on the use of restrictions involving graphs as a heuristic about coalitions for the problem coalition enumeration in order to consider a feasible coalition or not according to the density of the subgraph induced by the agents. Current works using the restriction graphs as heuristics to reduce the computational complexity, consider a coalition valid only if the subgraph formed by the agents of the coalition is connected. In this work it as experimentally verify for power law graphs, present in a variety of real graphs, that restricting availability coalition as a connected subgraph may in not prohibited a significant gain. However, they using a subgraphs with strong restrictions, in particular a clique, guarantees an exponential reduction in the number of considered coalition. There no are theorems calculate subgraphs or even the number of cliques on a type power law graph. In the present work it was possible to calculate values experimental for graphs of up to 17 vértices, being also presented analytics results for star graphs (Kn−1,1 ). Star graphs are an acceptable approximation, was they account for hubs, a characteristic structure of power law graphs. As future works can be cited the study of domains where the clique restriction is adequate as well as the development of an algorithm that incorporates the restriction for coalition counting.
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Javar, Shima. "Measurement and comparison of clustering algorithms". Thesis, Växjö University, School of Mathematics and Systems Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-1735.

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In this project, a number of different clustering algorithms are described and their workings explained. They are compared to each other by implementing them on number of graphs with a known architecture.

These clustering algorithm, in the order they are implemented, are as follows: Nearest neighbour hillclimbing, Nearest neighbour big step hillclimbing, Best neighbour hillclimbing, Best neighbour big step hillclimbing, Gem 3D, K-means simple, K-means Gem 3D, One cluster and One cluster per node.

The graphs are Unconnected, Directed KX, Directed Cycle KX and Directed Cycle.

The results of these clusterings are compared with each other according to three criteria: Time, Quality and Extremity of nodes distribution. This enables us to find out which algorithm is most suitable for which graph. These artificial graphs are then compared with the reference architecture graph to reach the conclusions.

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21

Braunschweig, Bertrand. "Aides à l'interprétation de simulations dynamiques : Application aux modèles de cinétique chimique". Paris 9, 1998. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=1998PA090018.

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Abstract (sommario):
La simulation dynamique est couramment utilisée dans de nombreux domaines scientifiques et techniques. Des simulateurs dynamiques sont mis entre les mains de plus en plus d’utilisateurs, grâce à l’accroissement des performances et aux progrès des interfaces homme machine, qui rend les modèles accessibles à tous. Mais les simulateurs sont toujours, et avant tout, des programmes qui produisent des séries de nombres à partir de séries de nombres, même si elles sont représentées par des graphiques. Cette thèse présente de nouvelles approches de l’interaction entre un simulateur numérique et son utilisateur. Le simulateur s’auto-examine pour fournir une interprétation de ses résultats, reposant sur une représentation des objets du domaine, exhibant les mécanismes cycliques dominants grâce à l’estimation de leurs gains instantanés, utilisant la notion d’épisodes pour découper la simulation en tranches homogènes, et accompagnant le tout de visualisations animées utilisant la structure du système modélisé. Ces nouvelles approches sont expérimentées dans le cadre de la modélisation en cinétique chimique, domaine d’application qui a un caractère exemplaire vue la variété des modèles et des comportements rencontrés; elles sont matérialisées au sein du programme Spike d’aide à la conduite d’expérimentation en cinétique chimique. Les mêmes concepts sont également mis en œuvre dans les deux domaines très différents que sont la propagation des ondes sismiques et la simulation de projet. L’ensemble a pour but d ‘apporter une contribution nouvelle pour la conception et la réalisation d’une véritable « intelligence des systèmes dynamiques »
Numerous scientific and technical domains make constant use of dynamical simulations. Such simulators are put in the hands of a growing number of users. This phenomenon is due both to the extraordinary increase in computing performance, and to better graphical user interfaces which make simulation models easy to operate. But simulators are still computer programs which produce series of numbers from other series of numbers, even if they are displayed graphically. This thesis presents new interaction paradigms between a dynamical simulator and its user. The simulator produces a self-made interpretation of its results, thanks to a dedicated representation of its domain with objects. It shows dominant cyclic mechanisms identified by their instantaneous loop gain estimates, it uses a notion of episodes for splitting the simulation into homogeneous time intervals, and completes this by animations which rely on the graphical structure of the System. These new approaches are demonstrated with examples from Chemical kinetics, because of the generic and exemplary characteristics of the encountered behaviors. They are implemented in the Spike software, a Software Platform for Interactive Chemical Kinetics Experiments. Similar concepts are also shown in two other domains: interpretation of seismic wave propagation, and simulation of large projects. Altogether the thesis is a step towards the delivery of a "Systems dynamics intelligence"
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22

Ahlberg, Helgee Ernst. "Improving drug discovery decision making using machine learning and graph theory in QSAR modeling". Göteborg : Dept. of Chemistry, University of Gothenburg, 2010. http://gupea.ub.gu.se/dspace/handle/2077/21838.

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23

Kinoshita, Yuji, Chiyomi Miyajima, Norihide Kitaoka e Kazuya Takeda. "Spoken dialog strategy based on understanding graph search". IEEE, 2009. http://hdl.handle.net/2237/13900.

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24

Muñoz, Mauro Enrique de Souza. "Desenvolvimento artificial autônomo de um grafo sensório-motor auto-organizável". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-28062016-081717/.

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Abstract (sommario):
A teoria de Jean Piaget sobre o desenvolvimento da inteligência tem sido utilizada na área de inteligência computacional como inspiração para a proposição de modelos de agentes cognitivos. Embora os modelos propostos implementem aspectos básicos importantes da teoria de Piaget, como a estrutura do esquema cognitivo, não consideram o problema da fundamentação simbólica e, portanto, não se preocupam com os aspectos da teoria que levam à aquisição autônoma da semântica básica para a organização cognitiva do mundo externo, como é o caso da aquisição da noção de objeto. Neste trabalho apresentamos um modelo computacional de esquema cognitivo inspirado na teoria de Piaget sobre a inteligência sensório-motora que se desenvolve autonomamente construindo mecanismos por meio de princípios computacionais pautados pelo problema da fundamentação simbólica. O modelo de esquema proposto tem como base a classificação de situações sensório-motoras utilizadas para a percepção, captação e armazenamento das relações causais determiníscas de menor granularidade. Estas causalidades são então expandidas espaço-temporalmente por estruturas mais complexas que se utilizam das anteriores e que também são projetadas de forma a possibilitar que outras estruturas computacionais autônomas mais complexas se utilizem delas. O modelo proposto é implementado por uma rede neural artificial feed-forward cujos elementos da camada de saída se auto-organizam para gerar um grafo sensóriomotor objetivado. Alguns mecanismos computacionais já existentes na área de inteligência computacional foram modificados para se enquadrarem aos paradigmas de semântica nula e do desenvolvimento mental autônomo, tomados como base para lidar com o problema da fundamentação simbólica. O grafo sensório-motor auto-organizável que implementa um modelo de esquema inspirado na teoria de Piaget proposto neste trabalho, conjuntamente com os princípios computacionais utilizados para sua concepção caminha na direção da busca pelo desenvolvimento cognitivo artificial autônomo da noção de objeto.
In artificial intelligence some cognitive agent models based on Jean Piaget\'s intelligence development theory have been proposed. Although the proposed models implement some fundamental aspects of this theory, like the cognitive schema struture, they do not consider the symbol grounding problem. Therefore, they are not concerned about the theoretical aspects that lead to the autonomous aquisition of the basic semantics needed by the cognitive organization of the agent\'s external world, as for the object concept aquisition. A computational cognitive scheme model inspired on Piaget\'s theory of the sensorimotor intelligence is presented. The scheme is autonomously built by computational mechanisms using principles considering the symbol grounding problem. The proposed scheme model uses sensory-motor situations to perceive, capture and store the finest grain deterministic causal relations. These causal relations are then expanded in time and space by more complex computational structures using the first ones. Those complex structures itselves are also designed in a way they can be used by more complex structures, expanding even further the causal relations in time and space. The proposed scheme model is implemented by an artificial neural network using feedforward architecture. The neural network output layer units progressively organized to compose a sensory-motor graph. Some known computational mechanisms from artificial inteligence were modified to fit to the zero semantic and the autonomous mental development paradigms, conceived in this work as the premises to handle the symbol grounding problem. The scheme model inspired by Piaget\'s theory implemented by the proposed self organizing sensorimotor graph in conjunction with the computational principles used, goes toward to the artificial autonomous cognitive development of the object concept.
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25

Livi, Federico. "Supervised Learning with Graph Structured Data for Transprecision Computing". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19714/.

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Abstract (sommario):
Nell'era dell'Internet of things, dei Big Data e dell'industria 4.0, la crescente richiesta di risorse e strumenti atti ad elaborare la grande quantità di dati e di informazioni disponibili in ogni momento, ha posto l'attenzione su problemi oramai non più trascurabili inerenti al consumo di energia e ai costi che ne derivano. Si tratta del cosiddetto powerwall, ovvero della difficoltà fisica dei macchinari di sostenere il consumo di potenza necessario per il processamento di moli di dati sempre più grandi e per l'esecuzione di task sempre più sofisticati. Tra le nuove tecniche che si sono affermate negli ultimi anni per tentare di arginare questo problema è importante citare la cosiddetta Transprecision Computing, approccio che si impegna a migliorare il consumo dell'energia a discapito della precisione. Infatti, tramite la riduzione di bit di precisione nelle operazioni di floating point, è possibile ottenere una maggiore efficienza energetica ma anche una decrescita non lineare della precisione di computazione. A seconda del dominio di applicazione, questo tradeoff può portare effettivamente ad importanti miglioramenti, ma purtroppo risulta ancora complesso trovare la precisione ottimale per tutte le variabili rispettando nel mentre un limite superiore relativo all'errore. In letteratura, questo problema è perciò affrontato utilizzando euristiche e metodologie che coinvolgono direttamente modelli di ottimizzazione e di machine learning. Nel presente elaborato, si cerca di migliorare ulteriormente questi approcci, introducendo nuovi modelli di machine learning basati anche sull'analisi di relazioni complesse tra le variabili. In questo senso, si arriva anche ad esaminare tecniche che lavorano direttamente su dati strutturati a grafo, tramite lo studio di reti neurali più complesse, le cosiddette graph convolutional networks.
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26

James, Andrew Michael. "A link-quality-aware graph model for cognitive radio network routing topology management /". Online version of thesis, 2007. http://hdl.handle.net/1850/5209.

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27

Hodé, Yann. "Contribution à l'interprétation d'images et vérification de la consistance d'un graphe". Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAD041/document.

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Abstract (sommario):
Dans cette thèse nous montrons que le raisonnement symbolique associé à la vérification de la consistance d'arc avec propagation de contraintes est un outil efficace pour interpréter les images. Nous montrons dans un premier temps que ce cadre théorique permet de vérifier l'organisation spatiale de différentes composantes d'un objet complexe dans une image. Nous proposons ensuite d'étendre l'utilisation de celui-ci à la reconnaissance sélective des formes décrites par des équations mathématiques, grâce à la notion de consistance d'hyper-arc à deux niveaux de contraintes. La pertinence et la faisabilité de cette approche ont été validées par de multiples tests. En outre, les résultats obtenus sur des images sur-segmentées montrent que la méthode proposée est résistante au bruit, même dans des conditions où les humains (dans certains cas d'agnosie visuelle) peuvent échouer. Ces résultats soutiennent l'intérêt du raisonnement symbolique dans la compréhension de l'image
In this thesis we show that symbolic reasoning associated with arc consistency checking is an efficient tool for images interpretation. We first show that this theoretical framework makes it possible to verify the spatial organization of different components of a complex object in an image. We then propose to extend the use of this framework to the selective recognition of shapes described by mathematical equations, thanks to the notion of hyper-arc consistency with bi-levels constraint. The relevance and feasibility of this approach have been validated by multiple tests. In addition, the results obtained on over-segmented images show that the proposed method is noise-resistant, even under conditions where humans (in some cases visual agnosia) may fail. These results support the interest of symbolic reasoning in image understanding
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28

Ghasemian, Davood, e Davood Ghasemian. "Groundwater Management Using Remotely Sensed Data in High Plains Aquifer". Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/623170.

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Abstract (sommario):
Groundwater monitoring in regional scales using conventional methods is challenging since it requires a dense network monitoring well system and regular measurements. Satellite measurement of time-variable gravity from the Gravity Recovery and Climate Experiment (GRACE) mission since 2002 provided an exceptional opportunity to observe the variations in Terrestrial Water Storage (TWS) from space. This study has been divided into 3 parts: First different satellite and hydrological model data have been used to validate the TSW measurements derived from GRACE in High Plains Aquifer (HPA). Terrestrial Water Storage derived from GRACE was compared to TWS derived from a water budget whose inputs determined from independent datasets. The results were similar to each other both in magnitude and timing with a correlation coefficient of 0.55. The seasonal groundwater storage changes are also estimated using GRACE and auxiliary data for the period of 2004 to 2009, and results are compared to the local in situ measurements to test the capability of GRACE in detecting groundwater changes in this region. The results from comparing seasonal groundwater changes from GRACE and in situ measurements indicated a good agreement both in magnitude and seasonality with a correlation coefficient of 0.71. This finding reveals the worthiness of GRACE satellite data in detecting the groundwater level anomalies and the benefits of using its data in regional hydrological modelling. In the second part of the study the feasibility of the GRACE TWS for predicting groundwater level changes is investigated in different locations of the High Plains Aquifer. The Artificial Neural Networks (ANNs) are used to predict the monthly groundwater level changes. The input data employed in the ANN include monthly gridded GRACE TWS based on Release-05 of GRACE Level-3, precipitation, minimum and maximum temperature which are estimated from Parameter elevation Regression on Independent Slopes Model (PRISM), and the soil moisture estimations derived from Noah Land Surface Model for the period of January 2004 to December 2009. All the values for mentioned datasets are extracted at the location of 21 selected wells for the study period. The input data is divided into 3 parts which 60% is dedicated to training, 20% to validation, and 20% to testing. The output to the developed ANNs is the groundwater level change which is compared to the US Geological Survey's National Water Information well data. Results from statistical downscaling of GRACE data leaded to a significant improvement in predicting groundwater level changes, and the trained ensemble multi-layer perceptron shows a "good" to a "very good" performance based on the obtained Nash-Sutcliff Efficiency which demonstrates the capability of these data for downscaling. In the third part of this study the soil moisture from 4 different Land Surface models (NOAH, VIC, MOSAIC, and CLM land surface models) which are accessible through NASA Global Land Data Assimilation System (GLDAS) is included in developing the ANNs and the results are compared to each other to quantify the effect of soil moisture in the downscaling process of GRACE. The relative importance of each predictor was estimated using connection weight technique and it was found that the GRACE TWS is a significant parameter in the performance of Artificial Neural Network ensembles, and based on the Root Mean Squared (RMSE) and the correlation coefficients associated to the models in which the soil moisture from Noah and CLM Land Surface Models are used, it is found that using these datasets in process of downscaling GRACE delivers a higher correlated simulation values to the observed values.
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29

Muncy, David. "Automated Conjecturing Approach for Benzenoids". VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4608.

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Benzenoids are graphs representing the carbon structure of molecules, defined by a closed path in the hexagonal lattice. These compounds are of interest to chemists studying existing and potential carbon structures. The goal of this study is to conjecture and prove relations between graph theoretic properties among benzenoids. First, we generate conjectures on upper bounds for the domination number in benzenoids using invariant-defined functions. This work is an extension of the ideas to be presented in a forthcoming paper. Next, we generate conjectures using property-defined functions. As the title indicates, the conjectures we prove are not thought of on our own, rather generated by a process of automated conjecture-making. This program, named Cᴏɴᴊᴇᴄᴛᴜʀɪɴɢ, is developed by Craig Larson and Nico Van Cleemput.
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30

Stefanoni, Giorgio. "Evaluating conjunctive and graph queries over the EL profile of OWL 2". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:232978e9-90a2-41cc-afd5-319518296894.

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OWL 2 EL is a popular ontology language that is based on the EL family of description logics and supports regular role inclusions,axioms that can capture compositional properties of roles such as role transitivity and reflexivity. In this thesis, we present several novel complexity results and algorithms for answering expressive queries over OWL 2 EL knowledge bases (KBs) with regular role inclusions. We first focus on the complexity of conjunctive query (CQ) answering in OWL 2 EL and show that the problem is PSpace-complete in combined complexity, the complexity measured in the total size of the input. All the previously known approaches encode the regular role inclusions using finite automata that can be worst-case exponential in size, and thus are not optimal. In our PSpace procedure, we address this problem by using a novel, succinct encoding of regular role inclusions based on pushdown automata with a bounded stack. Moreover, we strengthen the known PSpace lower complexity bound and show that the problem is PSpace-hard even if we consider only the regular role inclusions as part of the input and the query is acyclic; thus, our algorithm is optimal in knowledge base complexity, the complexity measured in the size of the KB, as well as for acyclic queries. We then study graph queries for OWL 2 EL and show that answering positive, converse- free conjunctive graph queries is PSpace-complete. Thus, from a theoretical perspective, we can add navigational features to CQs over OWL 2 EL without an increase in complexity. Finally, we present a practicable algorithm for answering CQs over OWL 2 EL KBs with only transitive and reflexive composite roles. None of the previously known approaches target transitive and reflexive roles specifically, and so they all run in PSpace and do not provide a tight upper complexity bound. In contrast, our algorithm is optimal: it runs in NP in combined complexity and in PTime in KB complexity. We also show that answering CQs is NP-hard in combined complexity if the query is acyclic and the KB contains one transitive role, one reflexive role, or nominals—concepts containing precisely one individual.
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31

Hammadi, Youssef. "Réduction d'un modèle 0D instationnaire et non-linéaire de thermique habitacle pour l’optimisation énergétique des véhicules automobiles". Thesis, Université Paris sciences et lettres, 2020. http://www.theses.fr/2020UPSLM027.

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L’utilisation de la climatisation automobile engendre physiquement une surconsommation de carburant. Pour diminuer cette surconsommation, il existe deux leviers principaux. Le premier consiste à travailler en amont sur la définition technique de l’habitacle et du système de climatisation. Le second levier consiste à optimiser les stratégies de contrôle. Dans les deux cas, il s’avère incontournable de construire des modèles de thermique habitacle précis et rapides à évaluer. Ce qui fait l’objet de cette thèse CIFRE du Groupe Renault. Dans un premier temps, une méthodologie de réduction de modèles est exploitée pour passer d’un modèle éléments finis 3D à un modèle 0D. Ce modèle 0D est basé sur des bilans de masse et d’énergie sur les différentes parois et zones d’air de la cabine. Il prend la forme d’un système d’équations algébro-différentielles non-linéaire qui peut être transcrit en Bond Graph. De plus, le modèle 0D exploite un couplage faible entre la thermique et la mécanique des fluides issue des calculs CFD (aéraulique et aérodynamique externe). Dans un deuxième temps, on applique une méthode d’apprentissage automatique aux données générées par le modèle 0D en vue de construire un modèle 0D réduit. Un plan d’expériences est considéré à cette étape. Du fait de la non-linéarité des échanges thermiques, nous avons développé une approche qui s’inspire des méthodes Gappy POD et EIM. La base réduite utilisée est une base multiphysique qui tient compte de plusieurs contributions (températures, enthalpies, flux thermiques et humidités). Le modèle réduit obtenu est un modèle hybride qui couple quelques équations physiques d’origine à un réseau de neurones artificiel. La méthodologie de réduction a été déployée sur des véhicules Renault. Les modèles réduits ont été intégrés dans la plateforme GREEN de synthèse énergétique qui modélise différentes thermiques (moteur, transmission, circuit de refroidissement, batterie, HVAC, boucle froide, sous-capot) en vue de faire des études de gestion thermique qui revêtent une importance particulière pour les véhicules électriques et hybrides. Les modèles réduits ont été validés sur plusieurs scénarios (boucle de régulation pour le confort thermique, cycle d’homologation, couplage HVAC) et ont permis d’obtenir des gains CPU allant jusqu’à 99% avec des erreurs moyennes de 0,5°C sur les températures et 0,6% sur les humidités relatives
The use of automotive air conditioning leads to a fuel overconsumption. To reduce this overconsumption, we can either work upstream on the technical definitions of the cabin and the HVAC system or optimize control strategies. In both cases, it is essential to build a cabin thermal model that well balances accuracy and complexity. This is the topic of this PhD thesis driven by Renault Group. First, a model reduction methodology is used to build a 0D model starting from a 3D finite element cabin thermal model. This 0D model is based on mass and energy balances on the different cabin walls and air zones. It consists of a nonlinear differential algebraic equations system which can be reinterpreted as a Bond Graph. In addition, the 0D model is based on a weak coupling between the thermal equations and the fluid mechanics ones resulting from CFD calculations (internal airflow and external aerodynamics). Secondly, we apply a machine learning method to the data generated by the 0D model in order to build a reduced 0D model. A design of experiment is considered at this stage. Due to the nonlinearity of the heat exchanges, we have developed an approach which is inspired by the Gappy POD and EIM methods. We use a multiphysics reduced basis that takes several contributions into account (temperatures, enthalpies, heat fluxes and humidities). The resulting reduced model is a hybrid model that couples some of the original physical equations to an artificial neural network. The reduction methodology has been validated on Renault vehicles. The reduced order models have been integrated into a vehicle system-level energetic simulation platform (GREEN) which models different thermics (engine, transmission, cooling system, battery, HVAC, refrigerant circuit, underhood) in order to perform thermal management studies which are of particular importance for electric and hybrid vehicles. The reduced order models have been validated on several scenarios (temperature control for thermal comfort, driving cycles, HVAC coupling) and have achieved CPU gains of up to 99% with average errors of 0.5 °C on temperatures and 0.6% on relative humidities
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Vicente, Elisa Lopes Santana 1985. "Geleia de uva 'BRS violeta' convencional e light : produção, caracterização e aceitabilidade /". Botucatu, 2016. http://hdl.handle.net/11449/144600.

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Orientador: Rogério Lopes Vieites
Banca: Elisangela Marques Jeronimo Torres
Banca: Flavia Aparecida de Carvalho Mariano Nasser
Resumo: O presente trabalho visou o desenvolvimento, aceitabilidade, análise nutricional e vida de prateleira de geleia convencional e light de uva cultivar BRS Violeta, utilizando a sucralose como edulcorante. Foram avaliados quatro tratamentos, sendo T1 - Convencional (60 % polpa: 40 % açúcar cristal), T2 - Light 1 (60 % polpa: 30 % açúcar cristal + 10 % sucralose), T3 - Light 2 (60 % polpa: 28 % açúcar cristal + 12 % sucralose), T4 - Light 3 (60 % polpa: 24 % açúcar cristal + 16 % sucralose). Para ocorrer à formação do gel característico da geleia, foram adicionados às formulações, pectina cítrica e ácido cítrico. As geleias foram avaliadas quanto teores de sólidos solúveis, pH, acidez total titulável, açúcar redutor e açúcar total, compostos fenólicos totais, atividade antioxidante total, pigmentos e flavonoides, cor instrumental, análise microbiológica, análise sensorial e avaliação energética, durante um período de 120 dias de armazenamento. Os teores de sólidos solúveis diminuíram durante o tempo avaliado. Houve pequena elevação nos teores de acidez total titulável, principalmente nas formulações light. Os compostos fenólicos e os antioxidantes decaíram durante o armazenamento. As versões de geleia Convencional e Light 2 demonstraram maior estabilidade no tempo armazenado, considerando assim viáveis para fabricação. Não ocorreu contaminação microbiológica nas geleias até os 120 dias de armazenamento, apresentando-se satisfatórias ao consumo. Todas as versões de geleias foram ...
Abstract:This work aimed at the development, acceptability, nutritional analysis and shelf life of conventional and light grape jam BRS Violeta using sucralose as a sweetener. We evaluated four treatments: T1 - Conventional (60% pulp: 40% crystal sugar), T2 - Light 1 (60% pulp: 30% granulated sugar + 10% sucralose), T3 - Light 2 (60% pulp: 28% crystal sugar + 12% sucralose), T4 - Light 3 (60% pulp 24% granulated sugar + 16% sucralose). For the formation of the characteristic occurs gel jam were added to the formulations, citric pectin and citric acid. The jams were evaluated for soluble solids, pH, titratable acidity, reducing sugar and the total sugar, total phenolics, total antioxidant activity, pigments and flavonoids, instrumental color, microbiological analysis, sensory analysis and energy assessment for a period of 120 days' storage. The soluble solids decreased during the evaluated time. There was a slight increase in levels of total acidity, especially in light formulations. The phenolics and antioxidants declined during storage. The Conventional and Light 2 jam versions showed greater stability in storage time, thus considering feasible to manufacture. There was no microbiological contamination jam until 120 days of storage, presenting satisfactory consumption. All versions of jams were well accepted by the consumer showing potential commercial value...
Mestre
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33

Almeida, Leonardo Jesus. "Detecção de comunidades em redes complexas utilizando estratégia multinível". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-29032010-161550/.

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Abstract (sommario):
O grande volume de dados armazenados em meio digital dificulta a anáalise e extração de informações por um ser humano sem que seja utilizada alguma ferramenta computacional inteligente. A área de Aprendizado de Máquina (AM) estuda e desenvolve algoritmos para o processamento e obtenção automática de conhecimento em dados digitais. Tradicionalmente, os algoritmos de AM modelam os dados analisados com base na abordagem proposicional; entretanto, recentemente com a disponibilidade de conjuntos de dados relacionais novas abordagens têm sido estudadas, como a modelagem utilizando redes complexas. Redes complexas é uma área de pesquisa recente e ativa que têm atraíido a atenção de pesquisadores e tem sido aplicada em diversos domínios. Mais especificamente, o estudo de detecção de comunidades em redes complexas é o tema principal deste trabalho. Detectar comunidades consiste em buscar grupos de vértices densamente conectados entre si em uma rede. Detectar a melhor divisão em comunidades de uma rede é um problema NP-completo, o que requer que o desenvolvimento de soluções viáveis baseiem-se em heurísticas como, por exemplo, medidas de qualidade. Newman prop^os a medida de modularidade Q que tem se mostrado eficiiente na análise de comunidades em redes. Este trabalho apresenta o Algoritmo Multinível de Otimização de Modularidade (AMOM) que é baseado a na otimização da medida de modularidade e integrado na estratégia multinível. A estratégia multinível é composta de três fases: (i) sucessivas compactações da rede inicial com base em contrações de arestas e fus~oes de vértices, (ii) particionamento da rede reduzida utilizando Algoritmo de Otimização de Modularidade (AOM) modificado, e (iii) sucessivas descompactações das redes intermediárias até que se retorne a rede inicial. O principal atrativo da estratégia é viabilizar a utilização de algoritmos custosos no particionamento do grafo compactado, uma vez que neste grafo a quantidade de vértices e arestas é uma fração reduzida em relação ao grafo inicial. O trabalho também propõe dois novos métodos para refinamento dos particionamentos durante a fase de uncoasening. A fiim de avaliar a escalabilidade e eficiiência da metodologia proposta foram realizados experimentos empíricos em redes consideradas benchmark. Os resultados demonstram um significativo ganho de desempenho, mantendo bons resultados qualitativos
Human based analysis of large amount of data is a hard task when no intelligent computer aid is provided. In this context, Machine Learning (ML) algorithms are aimed at automatically processing and obtaining knowledge from data. In general, ML algorithms use a propositional representation of data such as an attribute-value table. However, this model is not suitable for relational information modeling, which can be better accomplished using graphs or networks. In this context, complex networks have been call attention of scientific community recently and many applications in different domains have been developed. In special, one of complex networks research trends is the community detection field which is the main focus of this work. Community detection is the problem of finding dense and disjoint connected groups of vertices in a network. The problem is a well know NP-complete task which requires heuristics approaches, like quality measures, to be addressed. Newman introduced a specific quality measure called modularity that proved to be useful for analysis communities in networks. This work presents a new algorithm, called Multilevel Modularity Optimization Algorithm, based on modularity measure optimization integrated in a multilevel graph partitioning strategy. The multilevel graph partitioning scheme consists of three phases: (i) reduction of the size (coarsen) of original graph by collapsing vertices and edges, (ii) partitioning the coarsened graph, and (iii) uncoarsen it to construct a partition for the original graph. The rationale behind this strategy is to apply a computationally expensive method in a coarsened graph, i.e., with a significantly reduced number of vertices and edges. In addition, it is proposed two new methods that uses modularity and clustering coefficient for partition refinement. Empirical evaluation on benchmarks networks using this approach demonstrate a significant speed up gain compared to the original modularity-based algorithm, keeping a good quality clusters partitioning
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34

Watkins, Gregory Shroll. "A framework for interpreting noisy, two-dimensional images, based on a fuzzification of programmed, attributed graph grammars". Thesis, Rhodes University, 1998. http://hdl.handle.net/10962/d1004862.

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This thesis investigates a fuzzy syntactic approach to the interpretation of noisy two-dimensional images. This approach is based on a modification of the attributed graph grammar formalism to utilise fuzzy membership functions in the applicability predicates. As far as we are aware, this represents the first such modification of graph grammars. Furthermore, we develop a method for programming the resultant fuzzy attributed graph grammars through the use of non-deterministic control diagrams. To do this, we modify the standard programming mechanism to allow it to cope with the fuzzy certainty values associated with productions in our grammar. Our objective was to develop a flexible framework which can be used for the recognition of a wide variety of image classes, and which is adept at dealing with noise in these images. Programmed graph grammars are specifically chosen for the ease with which they allow one to specify a new two-dimensional image class. We implement a prototype system for Optical Music Recognition using our framework. This system allows us to test the capabilities of the framework for coping with noise in the context of handwritten music score recognition. Preliminary results from the prototype system show that the framework copes well with noisy images.
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35

MEDEIROS, Francisco Petrônio Alencar de. "Projeto e implementação de módulo TAOS-Graph da ferramenta iTAOS para análise e modelagem da tarefa". Universidade Federal de Campina Grande, 2003. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1557.

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Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-08-27T17:05:09Z No. of bitstreams: 1 FRANCISCO PETRÔNIO ALENCAR DE MEDEIROS - DISSERTAÇÃO PPGCC 2003..pdf: 3495874 bytes, checksum: 26f2cedd183b05f7571147e29242352b (MD5)
Made available in DSpace on 2018-08-27T17:05:09Z (GMT). No. of bitstreams: 1 FRANCISCO PETRÔNIO ALENCAR DE MEDEIROS - DISSERTAÇÃO PPGCC 2003..pdf: 3495874 bytes, checksum: 26f2cedd183b05f7571147e29242352b (MD5) Previous issue date: 2003-02-26
Esse trabalho apresenta o processo de construção e implementação do módulo TAOSGraph da ferramenta iTAOS. iTAOS é uma ferramenta gráfica que implementa o formalismo TAOS (Task and Action Oriented System) concebida para acompanhar o projetista de interfaces durante a fase de análise e descrição da tarefa dentro de um processo de desenvolvimento de interfaces, verificando a completude e consistência da representação. TAOS-Graph foi desenvolvido utilizando a metodologia MEDITE, uma metodologia guiada por modelos e baseada na tarefa para construção de interfaces ergonômicas. Os artefatos gerados ao final de cada etapa do processo de desenvolvimento de TAOS-Graph foram: a descrição TAOS da tarefa, a especificação conceitual da interação e o código da interface. Como recomenda a metodologia, foi realizada uma inspeção de conformidade da ferramenta iTAOS com as partes 14 (Menus), 16 (Manipulação direta) e 17 (Formulários) do padrão ISO 9241.
This work presents the process of construction and implementation of the TAOSGraph module of the iTAOS tool. iTAOS is a graphical tool that implements the TAOS formalism (Task and Action Oriented System) and is responsible for accompanying the interface designer (iTAOS user) during domain task’s description and analysis phases within the interface development process, verifying the completeness and the consistency of the representation. TAOS-Graph was developed using the methodology MEDITE, a methodology guided for models and based in the task for construction of ergonomic interfaces. The artefacts generated to the end of each stage of the development process of TAOS-Graph had been: description TAOS of the task, the conceptual specification of the interaction and the code of the interface. As recommends the methodology, iTAOS was carried through an inspection of conformity with the parts 14, 16 and 17 of the standard ISO 9241.
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36

Chennupati, Nikhil. "Recommending Collaborations Using Link Prediction". Wright State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1621899961924795.

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37

Fages, Jean-Guillaume. "Exploitation de structures de graphe en programmation par contraintes". Thesis, Nantes, Ecole des Mines, 2014. http://www.theses.fr/2014EMNA0190/document.

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De nombreuses applications informatiques nécessitent de résoudre des problèmes de décision qui sont difficiles d’un point de vue mathématique. La programmation par contraintes permet de modéliser et résoudre certains de ces problèmes, parfois définis sur des graphes. Au delà des difficultés intrinsèques aux problèmes étudiés, la taille des instances à traiter contribue à la difficulté de la résolution. Cette thèse traite de l’utilisation des graphes en programmation par contraintes, dans le but d’en améliorer la capacité de passage à l’échelle. Une première partie porte sur l’utilisation de contraintes pour résoudre des problèmes de graphes impliquant la recherche d’arbres, de chemins et de cycles Hamiltoniens. Ce sont des problèmes importants que l’on retrouve dans de nombreuses applications industrielles. Nous étudions à la fois le filtrage et les stratégies d’exploration de l’espace de recherche. Nous chercherons ensuite à nous extraire progressivement des problèmes classiquement définis sur les graphes pour exploiter ce concept sur des problèmes définis sur les entiers, voire les réels. Une seconde partie porte ainsi sur l’utilisation des graphes pour le filtrage de contraintes globales très répandues. Nous proposerons entre autres d’utiliser des graphes comme support pour décomposer dynamiquement des algorithmes de filtrage, de manière générique. Le fil conducteur de ces travaux sera d’une part l’utilisation du concept de graphe à la base de chaque raisonnement et d’autre part, la volonté pratique d’augmenter la taille des problèmes pouvant être traités en programmation par contraintes
Many IT applications require to solve decision problems which are hard from a mathematical point of view. Constraint-programming enables to model and solve some of these problems. Among them, some are defined over graphs. Beyond the difficulty stemming from each of these problems, the size of the instance to solve increases the difficulty of the task. This PhD thesis is about the use of graphs within constraint programming, in order to improve its scalability. First, we study the use of constraint-programming to solve some graph problems involving the computation of trees and Hamiltonian paths and cycles. These problems are important and can be found in many industrial applications. Both filtering and search are investigated. Next, we move on problems which are no longer defined in terms of graph properties. We then study the use of graphs to propagate global constraints. In particular, we suggest a generic schema, relying ona graph structure, to dynamically decompose filtering algorithms. The central theme in this work is the use of graph concepts at the origin of every reasoning and the practical will to increase the size of problems that can be addressed in constraint-programming
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38

Chrun, Ivan Rossato. "Mapas cognitivos fuzzy dinâmicos aplicados em vida artificial e robótica de enxame". Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2512.

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ANP
Este trabalho propõe o uso de Mapas Cognitivos Fuzzy Dinâmicos (DFCM, do inglês Dynamic Fuzzy Cognitive Maps), uma evolução dos Mapas Cognitivos Fuzzy (FCM), para o desenvolvimento de sistemas autônomos para tomada de decisões. O FCM representa o conhecimento de forma simbólica, através de conceitos e relações causais dispostas em um grafo. Na sua versão clássica, os FCMs são usados no desenvolvimento de modelos estáticos, sendo inapropriados para o desenvolvimento de modelos temporais ou dinâmicos devido à ocorrência simultânea de todas as causalidades em uma estrutura fixa dos grafos, i.e., os conceitos e suas relações causais são invariantes no tempo. O DFCM utiliza o mesmo formalismo matemático do FCM através de grafos, acrescentando funcionalidades, como por exemplo, a capacidade de auto adaptação através de algoritmos de aprendizagem de máquina e a possibilidade de inclusão de novos tipos de conceitos e relações causais ao modelo FCM clássico. A partir dessas inclusões, é possível construir modelos DFCM para tomada de decisões dinâmicas, as quais são necessárias no desenvolvimento de ferramentas inteligentes em áreas de conhecimento correlatas à engenharia, de modo especifico a construção de modelos aplicados em Robótica Autônoma. Em especial, para as áreas de Robótica de Enxame e Vida artificial, como abordados nesta pesquisa. O sistema autônomo desenvolvido neste trabalho aborda problemas com diferentes objetivos (como desviar de obstáculos, coletar alvos ou alimentos, explorar o ambiente), hierarquizando as ações necessárias para atingi-los, através do uso de uma arquitetura para o planejamento, inspirada no modelo clássico de Subsunção de Brooks, e uma máquina de estados para o gerenciamento das ações. Conceitos de aprendizagem de máquina, em especial Aprendizagem por Reforço, são empregadas no DFCM para a adaptação dinâmica das relações de casualidade, possibilitando o controlador a lidar com eventos não modelados a priori. A validação do controlador DFCM proposto é realizada por meio de experimentos simulados através de aplicações nas áreas supracitadas.
This dissertation proposes the use of Dynamic Fuzzy Cognitive Maps (DFCM), an evolution of Fuzzy Cognitive Maps (FCM), for the development of autonomous system to decision-taking. The FCM represents knowledge in a symbolic way, through concepts and causal relationships disposed in a graph. In its standard form, the FCMs are limited to the development of static models, in other words, classical FCMs are inappropriate for development of temporal or dynamic models due to the simultaneous occurrence of all causalities in a permanent structure, i.e., the concepts and the causal relationships are time-invariant. The DFCM uses the same mathematical formalism of the FCM, adding features to its predecessor, such as self-adaptation by means of machine learning algorithms and the possibility of inclusion of new types of concepts and causal relationships into the classical FCM model. From these inclusions, it is possible to develop DFCM models for dynamic decision-making problems, which are needed to the development of intelligent tools in engineering and other correlated areas, specifically, the construction of autonomous systems applied in Autonomous Robotic. In particular, to the areas of Swarm Robotics and Artificial Life, as approached in this research. The developed autonomous system deals with multi-objective problems (such as deviate from obstacle, collect target or feed, explore the environment), hierarchizing the actions needed to reach them, through the use of an architecture for planning, inspired by the Brook’s classical Subsumption model, and a state machine for the management of the actions. Learning machine algorithms, in particular Reinforcement Learning, are implemented in the DFCM to dynamically tune the causalities, enabling the controller to handle not modelled event a priori. The proposed DFCM model is validated by means of simulated experiments applied in the aforementioned areas.
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39

Faucheux, Cyrille. "Segmentation supervisée d'images texturées par régularisation de graphes". Thesis, Tours, 2013. http://www.theses.fr/2013TOUR4050/document.

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Dans cette thèse, nous nous intéressons à un récent algorithme de segmentation d’images basé sur un processus de régularisation de graphes. L’objectif d’un tel algorithme est de calculer une fonction indicatrice de la segmentation qui satisfait un critère de régularité ainsi qu’un critère d’attache aux données. La particularité de cette approche est de représenter les images à l’aide de graphes de similarité. Ceux-ci permettent d’établir des relations entre des pixels non-adjacents, et ainsi de procéder à un traitement non-local des images. Afin d’en améliorer la précision, nous combinons cet algorithme à une seconde approche non-locale : des caractéristiques de textures. Un nouveau terme d’attache aux données est dans un premier temps développé. Inspiré des travaux de Chan et Vese, celui-ci permet d’évaluer l’homogénéité d’un ensemble de caractéristiques de textures. Dans un second temps, nous déléguons le calcul de l’attache aux données à un classificateur supervisé. Entrainé à reconnaitre certaines classes de textures, ce classificateur permet d’identifier les caractéristiques les plus pertinentes, et ainsi de fournir une modélisation plus aboutie du problème. Cette seconde approche permet par ailleurs une segmentation multiclasse. Ces deux méthodes ont été appliquées à la segmentation d’images texturées 2D et 3D
In this thesis, we improve a recent image segmentation algorithm based on a graph regularization process. The goal of this method is to compute an indicator function that satisfies a regularity and a fidelity criteria. Its particularity is to represent images with similarity graphs. This data structure allows relations to be established between similar pixels, leading to non-local processing of the data. In order to improve this approach, combine it with another non-local one: the texture features. Two solutions are developped, both based on Haralick features. In the first one, we propose a new fidelity term which is based on the work of Chan and Vese and is able to evaluate the homogeneity of texture features. In the second method, we propose to replace the fidelity criteria by the output of a supervised classifier. Trained to recognize several textures, the classifier is able to produce a better modelization of the problem by identifying the most relevant texture features. This method is also extended to multiclass segmentation problems. Both are applied to 2D and 3D textured images
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40

Camonin, Martine. "Mephisto : un outil de validation de modèles tridimensionnels". Nancy 1, 1987. http://www.theses.fr/1987NAN10149.

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Le système présente a été développé dans le cadre d'un système d'interprétation de scènes tridimentionnelles (Trident). Le modèle choisi permet de décrire des familles d'objets génériques construits par unions de primitives. La tache du système Mephisto est de décider de la cohérence d'un modèle fourni par l'utilisateur avant qu'il ne soit utilisé par trident. Dans le contexte de la représentation choisie, un modèle peut être vu comme un graphe et/ou avec contraintes. Une stratégie de recherche de chemin dans un graphe et/ou, minimisant en moyenne les coûts de construction, à partir d'une évaluation des espérances de succès de cette construction
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41

Weninger, Timothy Edwards. "Link discovery in very large graphs by constructive induction using genetic programming". Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/1087.

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42

Gao, Xi. "Graph-based Regularization in Machine Learning: Discovering Driver Modules in Biological Networks". VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3942.

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Curiosity of human nature drives us to explore the origins of what makes each of us different. From ancient legends and mythology, Mendel's law, Punnett square to modern genetic research, we carry on this old but eternal question. Thanks to technological revolution, today's scientists try to answer this question using easily measurable gene expression and other profiling data. However, the exploration can easily get lost in the data of growing volume, dimension, noise and complexity. This dissertation is aimed at developing new machine learning methods that take data from different classes as input, augment them with knowledge of feature relationships, and train classification models that serve two goals: 1) class prediction for previously unseen samples; 2) knowledge discovery of the underlying causes of class differences. Application of our methods in genetic studies can help scientist take advantage of existing biological networks, generate diagnosis with higher accuracy, and discover the driver networks behind the differences. We proposed three new graph-based regularization algorithms. Graph Connectivity Constrained AdaBoost algorithm combines a connectivity module, a deletion function, and a model retraining procedure with the AdaBoost classifier. Graph-regularized Linear Programming Support Vector Machine integrates penalty term based on submodular graph cut function into linear classifier's objective function. Proximal Graph LogisticBoost adds lasso and graph-based penalties into logistic risk function of an ensemble classifier. Results of tests of our models on simulated biological datasets show that the proposed methods are able to produce accurate, sparse classifiers, and can help discover true genetic differences between phenotypes.
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43

Ge, Shengjie. "GPS radio occultation and the role of atmospheric pressure on spaceborne gravity estimation over Antarctica". Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1149070384.

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44

Chandra, Nagasai. "Node Classification on Relational Graphs using Deep-RGCNs". DigitalCommons@CalPoly, 2021. https://digitalcommons.calpoly.edu/theses/2265.

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Knowledge Graphs are fascinating concepts in machine learning as they can hold usefully structured information in the form of entities and their relations. Despite the valuable applications of such graphs, most knowledge bases remain incomplete. This missing information harms downstream applications such as information retrieval and opens a window for research in statistical relational learning tasks such as node classification and link prediction. This work proposes a deep learning framework based on existing relational convolutional (R-GCN) layers to learn on highly multi-relational data characteristic of realistic knowledge graphs for node property classification tasks. We propose a deep and improved variant, Deep-RGCNs, with dense and residual skip connections between layers. These skip connections are known to be very successful with popular deep CNN-architectures such as ResNet and DenseNet. In our experiments, we investigate and compare the performance of Deep-RGCN with different baselines on multi-relational graph benchmark datasets, AIFB and MUTAG, and show how the deep architecture boosts the performance in the task of node property classification. We also study the training performance of Deep-RGCNs (with N layers) and discuss the gradient vanishing and over-smoothing problems common to deeper GCN architectures.
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45

Doan, Le Anh. "Du micro véhicule aérien au nano véhicule aérien : études théoriques et expérimentales sur un insecte artificiel à ailes battantes". Thesis, Valenciennes, 2019. http://www.theses.fr/2019VALE0004/document.

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Au cours des dernières décennies, la possibilité d’exploiter les capacités de vol exceptionnelles des insectes a été à l’origine de nombreuses recherches sur l’élaboration de nano-véhicules aériens (NAVs) à ailes battantes. Cependant, lors de la conception de tels prototypes, les chercheurs doivent analyser une vaste gamme de solutions liées à la grande diversité des insectes volants pour identifier les fonctionnalités et les paramètres adaptés à leurs besoins. Afin d’alléger cette tâche, le but de ce travail est de développer un outil permettant à la fois d’examiner le comportement cinématique et énergétique d’un nano-véhicule aérien à ailes flexibles résonantes, et donc d'évaluer son efficacité. Cet objectif reste néanmoins extrêmement difficile à atteindre car il concerne des objets de très petites tailles. Aussi, nous avons choisi tout d’abord de travailler sur un micro-véhicule aérien (MAV) à ailes battantes. Il s’agit avant tout de valider l’outil de modélisation à travers une comparaison systématique des simulations avec des résultats expérimentaux effectués lors de l’actionnement des ailes, puis au cours du décollage et du vol stationnaire du prototype. Une partie des connaissances et expériences acquises pourra ensuite être utilisée afin de mieux comprendre le fonctionnement et identifier la distribution d'énergie au sein du NAV. Bien que les deux véhicules s’inspirent directement de la cinématique des ailes d'insectes, les mécanismes d'actionnement des ailes artificielles des deux prototypes ne sont pas les mêmes en raison de la différence de taille. Comme le NAV est plus petit, ces ailes ont un mouvement de battement à une fréquence plus élevée que celles du MAV, à l’instar de ce qui existe dans la nature. En conséquence, lorsque l’on passe du MAV au NAV, le mécanisme d’actionnement des ailes doit être adapté et cette différence nécessite d’une part, de revoir la conception, l'approche de modélisation et le processus d'optimisation, et d’autre part, de modifier le procédé de fabrication. Une fois ces améliorations apportées, nous avons obtenu des résultats de simulations en accord avec les tests expérimentaux. Le principal résultat de ce travail concerne l’obtention pour les deux prototypes, le MAV et le NAV, d’une cinématique appropriée des ailes, qui conduit à une force de portance équivalente au poids. Nous avons d’ailleurs démontré que le MAV était capable de décoller et d’avoir un vol stationnaire stable selon l’axe vertical. En tirant parti des modèles basés sur le langage Bond Graph, il est également possible d'évaluer les performances énergétiques de ces prototypes en fonction de la dynamique de l'aile. En conclusion, cette étude contribue à la définition des paramètres essentiels à prendre en compte lors de la conception et l'optimisation énergétique de micro et nano-véhicules à ailes battantes
In recent decades, the prospect of exploiting the exceptional flying capacities of insects has prompted much research on the elaboration of flapping-wing nano air vehicles (FWNAV). However, when designing such a prototype, designers have to wade through a vast array of design solutions that reflects the wide variety of flying insects to identify the correct combination of parameters to meet their requirements. To alleviate this burden, the purpose of this work is to develop a suitable tool to analyze the kinematic and power behavior of a resonant flexible-wing nano air vehicle. The key issue is evaluating its efficiency. However, this ultimate objective is extremely challenging as it is applied to the smallest flexible FWNAV. However, in this work, we worked first with a flapping-wing micro air vehicle (FWMAV) in order to have a tool for the simulation and experimentation of wing actuation, take-off and hovering. Some of the knowledge and experience acquired will then be transferred to better understand how our FWNAV works and identify the energy, power distribution. Although both of the vehicles employ the insect wing kinematics, their wings actuation mechanisms are not the same due to their sizes difference. Since the FWNAV is smaller, their wings flap at a higher frequency than the FWMAV as inspired by nature. As a consequence, from MAV to NAV, the wing actuation mechanism must be changed. Throughout this work, it can be seen clearly that this difference affects the whole vehicles development including the design, the manufacturing method, the modeling approach and the optimizing process. It has been demonstrated that the simulations are in good correlation with the experimental tests. The main result of this work is the proper wing kinematics of both FWMAV and FWNAV which leads to a lift to the weight ratio bigger and equal to one respectively. The FWMAV is even success to take-off and vertically stable hover. Moreover, taking advantage of the Bond Graph-based models, the evolution power according to the wing dynamic and the efficiency of the subsystem can be evaluated. In conclusion, this study shows the key parameters for designing and optimizing efficiency and the lift generated for two flapping wing vehicles in different size regimes
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46

Heinze, Joseph John. "A retrospective study of the treatment of grade II furcations with a tricomponent bioresorbable membrane". Oklahoma City : [s.n.], 2006.

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47

Koessler, Denise Renee. "A Predictive Model for Secondary RNA Structure Using Graph Theory and a Neural Network". Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etd/1684.

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In this work we use a graph-theoretic representation of secondary RNA structure found in the database RAG: RNA-As-Graphs. We model the bonding of two RNA secondary structures to form a larger structure with a graph operation called merge. The resulting data from each tree merge operation is summarized and represented by a vector. We use these vectors as input values for a neural network and train the network to recognize a tree as RNA-like or not based on the merge data vector. The network correctly assigned a high probability of RNA-likeness to trees identified as RNA-like in the RAG database, and a low probability of RNA-likeness to those classified as not RNA-like in the RAG database. We then used the neural network to predict the RNA-likeness of all the trees of order 9. The use of a graph operation to theoretically describe the bonding of secondary RNA is novel.
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Vaz, De Almeida Flavio-Guilherm. "Etudes des variations temporelles du champ de pesanteur terrestre à partir des données de la mission GRACE : application au bassin amazonien". Toulouse 3, 2009. http://thesesups.ups-tlse.fr/583/.

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L'objectif de ce travail est d'analyser les variations temporelles du champ de gravité, déterminées par la mission spatiale Gravity Recovery and Climate Experiment (GRACE), et ses relations avec la dynamique des eaux dans la région Amazonienne. À ce titre, nous avons cherché à développer une méthodologie pour les estimations des stocks d'eau dans des zones innondables non contrôlées ou difficilement accessibles. Pour ce faire, les coefficients de Stokes, calculés par le Groupe de Recherche de Geodesie Spatiale (GRGS) de Toulouse, ont été convertis en hauteur d'eau équivalente (HEE, Equivalent water Height - EWH en anglais) sur une période d'environ 4 ans (juillet de 2002 à mai 2006). Les valeurs d'HEE ainsi obtenues ont été comparées aux niveaux d'eau in-situ collectés par l'Agence Nationale de lEau brésilienne (ANA). Le choix du bassin Amazonien pour ce travail tient au fait qu'il présente en son centre, des amplitudes d'environ 1250mm de HEE, soit les plus grandes du monde. Cette amplitude est validée indirectement par comparaison entre les déplacements crustaux verticaux équivalents à cette charge superficielle et les mouvements verticaux de la stations GPS permanente de Manaus, à proximité du centre du bassin. Nous estimons que les erreurs associées à ces HEE sont au maximum de l'ordre de ~160mm HEE. Elles proviennent des erreurs des coefficients de Stokes, de la troncation du spectre et des erreurs de contamination (leakage) d'informations hydrologiques des bassins voisins. Finalement, HEE et les données de hauteur d'eau sont comparées dans les fleuves en terme d'hydrogéologie
The objective of this work is to analyze the temporal variations of the gravitational field, determined by the space mission Gravity Recovery and Climate Experiment (GRACE), and its relationships to the dynamics of water in the Amazon basin area. For this reason, was developed a methodology to estimate the water level in not controlled stocks or difficult to reach floodplains. With this intention, the Stokes coefficients, calculated by the Groupe de Recherche de Geodesie Spatiale (GRGS) Toulouse-FR, were converted into equivalent water height (EWH) for a ~4-year period (July-2002 to May-2006). In this basin, the amplitudes of EWH signal are the largest on Earth and can reach about 1250mm at the center of the basin. Analysis of the uncertainties indicate that it represents ~160 mm of EWH in this basin, including Stokes coefficient uncertainties (~130 mm), leakage errors (12 ~ 21 mm) and spectrum truncation (10 ~ 15 mm). This amplitude was indirectly validated by the comparison between equivalent vertical crustal displacements due to surface water load and the vertical movements of the Manaus GPS permanent monitoring stations, near to the center of the basin. The values of EWH thus obtained were compared with the in-situ water level collected by the Brazilian National Agency of Water (ANA) at 233 ground-based hydrometric stations (HS). Although EWH and HS measure different water bodies, high correlation, up to ~80% in most of the cases, is detected. This high correlation allows adjusting linear relationships between both series for the major tributaries of the Amazon. The regression coefficients decrease from upstream to downstream along the rivers reaching the theoretical value 1 at the mouth of the Amazon in the Atlantic Ocean
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49

Wu, Qinghua. "Problèmes de clique maximum avec applications à la coloration de graphe". Phd thesis, Université d'Angers, 2013. http://tel.archives-ouvertes.fr/tel-01005886.

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Le problème de la clique maximum (MCP) est un problème d'optimisation combinatoire important avec un large éventail d'applications pratiques dans de nombreux domaines, y compris la recherche d'information, l'analyse de la transmission du signal, la théorie de la classification, l'économie, la planification et l'ingénierie biomédicale. En outre, un certain nombre de problèmes d'optimisation combinatoire sont étroitement liés au MCP, tels que la coloration de graphe, la somme coloration, réglez détermination du gagnant emballage et optimale. Cette thèse est consacrée à l'élaboration d'approches heuristiques efficaces pour s'attaquer au problème de la clique maximum et ses généralisations. Pour atteindre cet objectif, nous avons développé une approche de recherche tabou adaptative multistart pour le problème de clique maximum classique, un algorithme recherche tabou multi-voisinage pour la clique maximum de sommets pondérés, et une méthode métaheuristique hybride pour le problème de la clique maximum d'arêtes pondérés. En outre, nous appliquons ces méthodes heuristiques développées pour résoudre ces problèmes difficiles qui sont étroitement liés au problème de la clique maximum. Tous les algorithmes sont mis en oeuvre et testés avec succès sur un certain nombre de cas de référence provenant de divers domaines d'application. Les méthodes proposées concurrencent favorablement les autres approches de l'état de l'art.
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50

Ishida, Shoichi. "Development of an AI-Driven Organic Synthesis Planning Approach with Retrosynthesis Knowledge". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263605.

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