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Migration patterns and survival of Busseola fusca larvae in maize plantings with different ratios of Bt and non-Bt seed / Jaco MaraisMarais, Jaco January 2014 (has links)
The high-dose/refuge strategy is used globally to manage insect resistance development in genetically modified crops with insecticidal properties (Bt crops). The “refuge in a bag” (RIB) strategy is also being considered for deployment against several pest species. Busseola fusca, the target pest of Bt maize in South Africa, evolved resistance to Cry1Ab proteins. The objective of this study was to determine whether migrating B. fusca larvae are effectively controlled using the RIB strategy. A field study with a single-gene event (Cry1Ab) and a “pyramid” event (Cry1A.105 + Cry2Ab2) was conducted in which the migration patterns of B. fusca larvae in plots with different seed mixture treatments were studied. The experiment consisted of five seed mixture ratios (5%, 10%, 15%, 20% non-Bt seed and 100 % non-Bt seed as control). Natural infestation was augmented by artificial inoculation with neonate larvae into the central non-Bt maize plant of each plot. Rate of larval survival and migration, measured in terms of increase in number of plants per plot that exhibited borer damage was recorded at weekly intervals until flowering. A laboratory study was conducted to determine larval growth and survival when simulating migration between Bt and non-Bt maize plants. A feeding experiment in which larvae were reared on different types of maize (Bt and non-Bt) was conducted and larval survival and mass recorded after a 7-day feeding period. The incidence of damaged ears, stem damage and damaged internodes per stem were recorded and relationships between these variables determined by means of correlation analyses. A review was conducted in order to identify and discuss similarities and differences between the high-dose/refuge and seed mixture strategies. This was done to determine which strategy would be the most appropriate insect resistance management (IRM) strategy against B. fusca. The rate of survival and migration of B. fusca larvae was significantly higher in the plots with maize expressing Cry1Ab and control plots, than in plots with the pyramid Bt event. Older larvae exhibited improved growth and survival in the laboratory experiment when they were transferred from non-Bt to Bt plants. Positive correlations were found between early and late season damage, although some weaker than others. Plants of the “pyramid event” suffered less late-season damage than those of the single-gene event. Since the increase in number of damaged maize plants over time is associated with migration of older and larger larvae, the observed tendencies may indicate that the assumed high-dose does not kill larvae above a certain developmental stage. The high-dose refuge strategy seems to be the better option for delaying resistance development. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
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Stability studies of intravenous cyclosporine preparations stored in non-PVC containersLi, Mengqing 12 1900 (has links)
Dans cette étude, la stabilité de préparations intraveineuses de cyclosporine (0.2 et 2.5 mg/mL dans NaCl 0.9% ou dextrose 5%) entreposées dans des seringues de polypropylène, des sacs de polypropylène-polyoléfine et des sacs de vinyle acétate d’éthylène a été évaluée. Une méthode HPLC indicatrice de la stabilité à base de méthanol a été développée et validée suite a des études de dégradation forcée. Les solutions évaluées ont été préparées de façon aseptique, puis entreposées à 25°C. La stabilité chimique a été évaluée par HPLC et la stabilité physique a été évaluée par inspection visuelle et aussi par diffusion dynamique de la lumière (DLS). Tous les échantillons sont demeurés stables chimiquement et physiquement dans des sacs de polypropylène-polyoléfine (>98% de cyclosporine récupérée après 14 jours). Lorsqu’entreposés dans des seringues de polypropylène, des contaminants ont été extraits des composantes de la seringue. Toutefois, aucune contamination n’a été observée après 10 min de contact entre la préparation de cyclosporine non-diluée et ces mêmes seringues. Les préparations de 2.5 mg/mL entreposées dans des sacs de vinyle acétate d’éthylène sont demeurés stables chimiquement et physiquement (>98% de cyclosporine récupérée après 14 jours). Toutefois, une adsorption significative a été observée avec les échantillons 0.2 mg/mL entreposés dans des sacs de vinyle acétate d’éthylène (<90% de cyclosporine récupéré après 14 jours). Une étude cinétique a démontré une bonne corrélation linéaire entre la quantité adsorbée et la racine carrée du temps de contact (r2 > 0.97). Un nouveou modèle de diffusion a été établi. En conclusion, les sacs de polypropylène-polyoléfine sont le meilleur choix; les seringues de polypropylène présentent un risque de contamination, mais sont acceptables pour un transfert rapide. Les sacs de vinyle acétate d’éthylène ne peuvent être recommandés à cause d’un problème d’adsorption. / In the present study, the stability of intravenous cyclosporine preparations (0.2 and 2.5 mg/mL in 0.9% sodium chloride injection or 5% dextrose injection) stored in polypropylene (PP) syringes, polypropylene–polyolefin (PP-PO) bags and ethylene vinyl acetate (EVA) bags was evaluated. A methanol-based high-performance liquid chromatography (HPLC) method was developed and validated to be stability-indicating by stress degradation tests. The test solutions were aseptically prepared and stored at 25 °C. Chemical stability was evaluated by HPLC assay. Physical stability was assessed by visual inspection and a dynamic light scattering (DLS) method. All samples were chemically stable (> 98% of recovered cyclosporine) and physically stable when stored in polypropylene–polyolefin bags for 14 days. When stored in polypropylene syringes, some impurities were leached. However, no leaching was detected when the syringes were exposed to undiluted intravenous cyclosporine for 10 minutes. The preparations of 2.5 mg/mL were chemically and physically stable as stored in ethylene vinyl acetate bags for a period of 14 days (> 98% of recovered cyclosporine), while significant cyclosporine adsorption occurred on the samples of 0.2 mg/mL (< 90 % of recovered cyclosporine) after 14 days. Kinetic study showed that good linear correlations were achieved by plotting the adsorption amount versus square root of contact time (r2 > 0.97). A novel diffusion model was established and successfully predicted long-term drug stability. In conclusion, polypropylene–polyolefin bags were the best choice; syringes were inferior because of leachables. However, they were safe for preparation and transferring undiluted intravenous cyclosporine. Ethylene vinyl acetate bags cannot be recommended due to cyclosporine adsorption.
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Evaluation of Membrane Treatment Technology to Optimize and Reduce Hypersalinity Content of Produced Brine for Reuse in Unconventional Gas WellsEboagwu, Uche 2011 August 1900 (has links)
Over 18 billion barrels of waste fluids are generated annually from oil and gas production in the United States. As a large amount of water is used for oilfield operations, treating and reusing produced water can cut the consumption of fresh water in well sites. This research has helped to develop a membrane process train for a mobile produced water treatment unit for treating oilfield produced brine for reuse.
To design the process train, over 30 sets of combination tests at pilot laboratory scale were performed using pretreatment, microfiltration and nanofiltration processes.
Membrane performance was selected based on high flux separation efficiency, high tolerance for solids and fluid treatments. Over 95 % solids rejection and greater than 80 % oil removal efficiency were obtained in all these tests.
Process train (pre-treatment and membrane) performance was monitored by chemical analysis of permeate and models fitting experimental data for the process. From the results, hydrocarbon rejection was analyzed; total organic carbon rejection was 47.9 %, total carbon content averaged 37.3 % rejection and total inorganic carbon rejection was at 3.66 %. BTEX removal efficiency ranged from 0.98 % to 52.7 % with the progressive pretreatment methods of using cartridge filters. The nanofiltration membrane showed significant reduction in total dissolved solids and in both anionic and cationic species.
The process train is seen to follow a sequence of treatment from cartridge and oil removal filter treatment to microfiltration treatment to ultrafiltration, followed by nanofiltration for the purpose of this research. Further research still needs to be done on to determine the kind of analytical test which will give real time feedback on effectiveness of filters.
In summary, the process train developed by TAMU-GPRI possesses distinct advantages in treating oilfield produced brine using membrane technology. These advantages include high quality of permeate, reduced sludge and the possibility of total recycle water systems. The small space requirement, moderate capital costs and ease of operation associated with the use of the mobile unit membrane technology also makes it a very competitive alternative to conventional technologies.
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Regulated rewriting in formal language theoryTaha, Mohamed A. M. S 03 1900 (has links)
Thesis (MSc (Mathematical Sciences))--University of Stellenbosch, 2008. / Context-free grammars are well-studied and well-behaved in terms of decidability, but many
real-world problems cannot be described with context-free grammars. Grammars with regulated
rewriting are grammars with mechanisms to regulate the applications of rules, so that
certain derivations are avoided. Thus, with context-free rules and regulated rewriting mechanisms,
one can often generate languages that are not context-free.
In this thesis we study grammars with regulated rewriting mechanisms. We consider problems
in which context-free grammars are insufficient and in which more descriptive grammars
are required. We compare bag context grammars with other well-known classes of grammars
with regulated rewriting mechanisms. We also discuss the relation between bag context grammars
and recognizing devices such as counter automata and Petri net automata. We show
that regular bag context grammars can generate any recursively enumerable language. We
reformulate the pumping lemma for random permitting context languages with context-free
rules, as introduced by Ewert and Van der Walt, by using the concept of a string homomorphism.
We conclude the thesis with decidability and complexity properties of grammars with
regulated rewriting.
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Verificação distribuída de modelos: investigando o uso de grades computacionais. / Distributed verification of models: investigating the use of computational grids.BARBOSA, Paulo Eduardo e Silva. 29 August 2018 (has links)
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Previous issue date: 2007-02-23 / Todo programador ou engenheiro de software lida com um problema crônico na concepção
de seus sistemas: violações das especificações ou requisitos de projeto. Essas violações
necessitam de uma captura imediata, pois geralmente originam falhas que só podem
ser descobertas tardiamente, a um custo de reparo bastante elevado. Nos últimos anos, pesquisadores da ciência da computação estão conseguindo um progressonotávelnodesenvolvimentodetécnicaseferramentasqueverificamautomaticamente
requisitos e projeto. A abordagem em maior evidência chama-se verificação de modelos
(model-checking). Verificação de modelos é uma técnica formal e algorítmica de se fazer
verificação de propriedades de sistemas com um espaço de estados finito. Suas principais
vantagens são o poder de automação e a qualidade dos resultados produzidos. Porém, esta técnica sofre de um problema fundamental — a explosão do espaço de estados — que se deve ao crescimento exponencial na estrutura que representa o comportamento de sistemas e à falta de recursos computacionais disponíveis para lidar com grandes quantidades de informação sobre o comportamento dos sistemas sob verificação. Este trabalho concentra-se em verificação de modelos utilizando plataformas de distribuição como tentativa de aliviar o problema citado. Mais detalhadamente, investigamos o uso de grades computacionais que rodam aplicações bag-of-tasks e formulamos algoritmos
específicos para o processo de verificação. Aplicações bag-of-tasks são aplicações paralelas cujas tarefas são independentes entre si. Elas são as aplicações mais apropriadas para grades computacionais por permitirem heterogeneidade dos recursos. Aplicamos ferramentas de grades computacionais como uma camada entre a ferramenta de verificação e os recursos distribuídos compartilhados existentes e comparamos os quesitos desempenho e escala nos sistemas a serem verificados em relação às versões centralizadas de verificadores. A plataforma empregada na distribuição é muito atrativa no quesito custo, controle e escala. Através do compartilhamento de uma simples máquina, o engenheiro de sistemas ganha acesso a uma comunidade provedora de uma grande quantidade de recursos heterogêneos e automaticamente gerenciados para se fazer computação paralela seguindo sua filosofia. Durante o trabalho, essas vantagens são comparadas com suas desvantagens, como o alto custo de comunicação e a dificuldade de particionar o processo, por exemplo. O trabalho envolveu a produção das seguintes ferramentas: uma API genérica para a geração distribuída de grafos que representam o comportamento de sistemas concorrentes sobre plataformas de grades computacionais bag-of-tasks, um protótipo de verificação CTL que age de duas maneiras distintas, sendo on-the-fly durante a geração do espaço de estados ou sobre esse espaço de estados distribuído representado explicitamente seguindo a mesma filosofia de comunicação e versões simplificadas de simuladores de sistemas concorrentes sob alguns formalismos baseados em redes de Petri. Resultados experimentais sobre a aplicação deste ferramental são apresentados. / Every programmer or software engineer deals with a chronic problem during the conception of their systems: violations in the project requirements. These violations need to be discovered early be cause they generally produce errors that can be discovered later, at a very expensive cost to repair. In recent years, researchers in computer science are obtaining a notable progress in the development of techniques and tools to automatically verify requirements and designs. The most evidently approach is called model-checking. Model checking is a formal and algorithmic technique to perform properties verification in a finite state space of systems. Its main advantages are the automation power and the quality of the produced results. However this technique suffers from one big and foundamental problem - the state space explosion which is the absense of computational resources available today’s to deal with large amounts of information about the behavior of the systems under verification. This work investigates a solution to verify models in a distributed way using computational grids which runs bag-of-tasks applications, alleviating the mentioned problem. Bagof-tasks applications are those parallel applications which tasks arei ndependent of each other and are the applications most suited for computational grids because they allow heterogeneity between resources. We employ computational grid tools as a layer between between the verificationtooland the distributed shared resources. This verification is performed by adapted CTL algorithms to the bag-of-tasks philosophy.
So we intend to obtain improvements in speed-up and scalability in the systems to be checked when compared to centralized versions of verifiers produced in side the group. Moreover,the employed middleware in the distribution is very attractive in the cost and control aspects. By sharing a single machine, the system engineer obtains access to a community that provides large amounts of heterogeneous resources automatically managed to perform parallel computation. This work included the production of the following tools: a generic API to the distributed generation of graphs that describes the behavior of concurrent systems under bag-of-tasks computational grids platforms, a prototype to check for CTL properties using on-the-fly algorithms or iterating over the generated fragments of the distributed graph. We also implemented simplified versions of simulators of concurrent systems following some formalisms based on Petri nets. Experimental results are also presented.
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Image-based detection and classification of allergenic pollen / Détection et classification des pollens allergisants basée sur l'imageLozano Vega, Gildardo 18 June 2015 (has links)
Le traitement médical des allergies nécessite la caractérisation des pollens en suspension dans l’air. Toutefois, cette tâche requiert des temps d’analyse très longs lorsqu’elle est réalisée de manière manuelle. Une approche automatique améliorerait ainsi considérablement les applications potentielles du comptage de pollens. Les dernières techniques d’analyse d’images permettent la détection de caractéristiques discriminantes. C’est pourquoi nous proposons dans cette thèse un ensemble de caractéristiques pertinentes issues d’images pour la reconnaissance des principales classes de pollen allergènes. Le cœur de notre étude est l’évaluation de groupes de caractéristiques capables de décrire correctement les pollens en termes de forme, texture, taille et ouverture. Les caractéristiques sont extraites d’images acquises classiquement sous microscope, permettant la reproductibilité de la méthode. Une étape de sélection des caractéristiques est appliquée à chaque groupe pour évaluer sa pertinence.Concernant les apertures présentes sur certains pollens, une méthode adaptative de détection, localisation et comptage pour différentes classes de pollens avec des apparences variées est proposée. La description des apertures se base sur une stratégie de type Sac-de-Mots appliquée à des primitives issues des images. Une carte de confiance est construite à partir de la confiance donnée à la classification des régions de l’image échantillonnée. De cette carte sont extraites des caractéristiques propres aux apertures, permettant leur comptage. La méthode est conçue pour être étendue de façon modulable à de nouveaux types d’apertures en utilisant le même algorithme mais avec un classifieur spécifique.Les groupes de caractéristiques ont été testés individuellement et conjointement sur les classes de pollens les plus répandues en Allemagne. Nous avons montré leur efficacité lors d’une classification de type SVM, notamment en surpassant la variance intra-classe et la similarité inter-classe. Les résultats obtenus en utilisant conjointement tous les groupes de caractéristiques ont abouti à une précision de 98,2 %, comparable à l’état de l’art. / The correct classification of airborne pollen is relevant for medical treatment of allergies, and the regular manual process is costly and time consuming. An automatic processing would increase considerably the potential of pollen counting. Modern computer vision techniques enable the detection of discriminant pollen characteristics. In this thesis, a set of relevant image-based features for the recognition of top allergenic pollen taxa is proposed and analyzed. The foundation of our proposal is the evaluation of groups of features that can properly describe pollen in terms of shape, texture, size and apertures. The features are extracted on typical brightfield microscope images that enable the easy reproducibility of the method. A process of feature selection is applied to each group for the determination of relevance.Regarding apertures, a flexible method for detection, localization and counting of apertures of different pollen taxa with varying appearances is proposed. Aperture description is based on primitive images following the Bag-of-Words strategy. A confidence map is built from the classification confidence of sampled regions. From this map, aperture features are extracted, which include the count of apertures. The method is designed to be extended modularly to new aperture types employing the same algorithm to build individual classifiers.The feature groups are tested individually and jointly on of the most allergenic pollen taxa in Germany. They demonstrated to overcome the intra-class variance and inter-class similarity in a SVM classification scheme. The global joint test led to accuracy of 98.2%, comparable to the state-of-the-art procedures.
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Reconnaissance perceptuelle des objets d’Intérêt : application à l’interprétation des activités instrumentales de la vie quotidienne pour les études de démence / Perceptual object of interest recognition : application to the interpretation of instrumental activities of daily living for dementia studiesBuso, Vincent 30 November 2015 (has links)
Cette thèse est motivée par le diagnostic, l’évaluation, la maintenance et la promotion de l’indépendance des personnes souffrant de maladies démentielles pour leurs activités de la vie quotidienne. Dans ce contexte nous nous intéressons à la reconnaissance automatique des activités de la vie quotidienne.L’analyse des vidéos de type égocentriques (où la caméra est posée sur une personne) a récemment gagné beaucoup d’intérêt en faveur de cette tâche. En effet de récentes études démontrent l’importance cruciale de la reconnaissance des objets actifs (manipulés ou observés par le patient) pour la reconnaissance d’activités et les vidéos égocentriques présentent l’avantage d’avoir une forte différenciation entre les objets actifs et passifs (associés à l’arrière plan). Une des approches récentes envers la reconnaissance des éléments actifs dans une scène est l’incorporation de la saillance visuelle dans les algorithmes de reconnaissance d’objets. Modéliser le processus sélectif du système visuel humain représente un moyen efficace de focaliser l’analyse d’une scène vers les endroits considérés d’intérêts ou saillants,qui, dans les vidéos égocentriques, correspondent fortement aux emplacements des objets d’intérêt. L’objectif de cette thèse est de permettre au systèmes de reconnaissance d’objets de fournir une détection plus précise des objets d’intérêts grâce à la saillance visuelle afin d’améliorer les performances de reconnaissances d’activités de la vie de tous les jours. Cette thèse est menée dans le cadre du projet Européen Dem@care.Concernant le vaste domaine de la modélisation de la saillance visuelle, nous étudions et proposons une contribution à la fois dans le domaine "Bottom-up" (regard attiré par des stimuli) que dans le domaine "Top-down" (regard attiré par la sémantique) qui ont pour but d’améliorer la reconnaissance d’objets actifs dans les vidéos égocentriques. Notre première contribution pour les modèles Bottom-up prend racine du fait que les observateurs d’une vidéo sont normalement attirés par le centre de celle-ci. Ce phénomène biologique s’appelle le biais central. Dans les vidéos égocentriques cependant, cette hypothèse n’est plus valable.Nous proposons et étudions des modèles de saillance basés sur ce phénomène de biais non central.Les modèles proposés sont entrainés à partir de fixations d’oeil enregistrées et incorporées dans des modèles spatio-temporels. Lorsque comparés à l’état-de-l’art des modèles Bottom-up, ceux que nous présentons montrent des résultats prometteurs qui illustrent la nécessité d’un modèle géométrique biaisé non-centré dans ce type de vidéos. Pour notre contribution dans le domaine Top-down, nous présentons un modèle probabiliste d’attention visuelle pour la reconnaissance d’objets manipulés dans les vidéos égocentriques. Bien que les bras soient souvent source d’occlusion des objets et considérés comme un fardeau, ils deviennent un atout dans notre approche. En effet nous extrayons à la fois des caractéristiques globales et locales permettant d’estimer leur disposition géométrique. Nous intégrons cette information dans un modèle probabiliste, avec équations de mise a jour pour optimiser la vraisemblance du modèle en fonction de ses paramètres et enfin générons les cartes d’attention visuelle pour la reconnaissance d’objets manipulés. [...] / The rationale and motivation of this PhD thesis is in the diagnosis, assessment,maintenance and promotion of self-independence of people with dementia in their InstrumentalActivities of Daily Living (IADLs). In this context a strong focus is held towardsthe task of automatically recognizing IADLs. Egocentric video analysis (cameras worn by aperson) has recently gained much interest regarding this goal. Indeed recent studies havedemonstrated how crucial is the recognition of active objects (manipulated or observedby the person wearing the camera) for the activity recognition task and egocentric videospresent the advantage of holding a strong differentiation between active and passive objects(associated to background). One recent approach towards finding active elements in a sceneis the incorporation of visual saliency in the object recognition paradigms. Modeling theselective process of human perception of visual scenes represents an efficient way to drivethe scene analysis towards particular areas considered of interest or salient, which, in egocentricvideos, strongly corresponds to the locus of objects of interest. The objective of thisthesis is to design an object recognition system that relies on visual saliency-maps to providemore precise object representations, that are robust against background clutter and, therefore,improve the recognition of active object for the IADLs recognition task. This PhD thesisis conducted in the framework of the Dem@care European project.Regarding the vast field of visual saliency modeling, we investigate and propose a contributionin both Bottom-up (gaze driven by stimuli) and Top-down (gaze driven by semantics)areas that aim at enhancing the particular task of active object recognition in egocentricvideo content. Our first contribution on Bottom-up models originates from the fact thatobservers are attracted by a central stimulus (the center of an image). This biological phenomenonis known as central bias. In egocentric videos however this hypothesis does not alwayshold. We study saliency models with non-central bias geometrical cues. The proposedvisual saliency models are trained based on eye fixations of observers and incorporated intospatio-temporal saliency models. When compared to state of the art visual saliency models,the ones we present show promising results as they highlight the necessity of a non-centeredgeometric saliency cue. For our top-down model contribution we present a probabilisticvisual attention model for manipulated object recognition in egocentric video content. Althougharms often occlude objects and are usually considered as a burden for many visionsystems, they become an asset in our approach, as we extract both global and local featuresdescribing their geometric layout and pose, as well as the objects being manipulated. We integratethis information in a probabilistic generative model, provide update equations thatautomatically compute the model parameters optimizing the likelihood of the data, and designa method to generate maps of visual attention that are later used in an object-recognitionframework. This task-driven assessment reveals that the proposed method outperforms thestate-of-the-art in object recognition for egocentric video content. [...]
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Analyse et interprétation de scènes visuelles par approches collaboratives / Analysis and interpretation of visual scenes through collaborative approaches / Analiza si interpretarea scenelor vizuale prin abordari colaborativeStrat, Sabin Tiberius 04 December 2013 (has links)
Les dernières années, la taille des collections vidéo a connu une forte augmentation. La recherche et la navigation efficaces dans des telles collections demande une indexation avec des termes pertinents, ce qui nous amène au sujet de cette thèse, l’indexation sémantique des vidéos. Dans ce contexte, le modèle Sac de Mots (BoW), utilisant souvent des caractéristiques SIFT ou SURF, donne de bons résultats sur les images statiques. Notre première contribution est d’améliorer les résultats des descripteurs SIFT/SURF BoW sur les vidéos en pré-traitant les vidéos avec un modèle de rétine humaine, ce qui rend les descripteurs SIFT/SURF BoW plus robustes aux dégradations vidéo et qui leurs donne une sensitivité à l’information spatio-temporelle. Notre deuxième contribution est un ensemble de descripteurs BoW basés sur les trajectoires. Ceux-ci apportent une information de mouvement et contribuent vers une description plus riche des vidéos. Notre troisième contribution, motivée par la disponibilité de descripteurs complémentaires, est une fusion tardive qui détermine automatiquement comment combiner un grand ensemble de descripteurs et améliore significativement la précision moyenne des concepts détectés. Toutes ces approches sont validées sur les bases vidéo du challenge TRECVid, dont le but est la détection de concepts sémantiques visuels dans un contenu multimédia très riche et non contrôlé. / During the last years, we have witnessed a great increase in the size of digital video collections. Efficient searching and browsing through such collections requires an indexing according to various meaningful terms, bringing us to the focus of this thesis, the automatic semantic indexing of videos. Within this topic, the Bag of Words (BoW) model, often employing SIFT or SURF features, has shown good performance especially on static images. As our first contribution, we propose to improve the results of SIFT/SURF BoW descriptors on videos by pre-processing the videos with a model of the human retina, thereby making these descriptors more robust to video degradations and sensitivite to spatio-temporal information. Our second contribution is a set of BoW descriptors based on trajectories. These give additional motion information, leading to a richer description of the video. Our third contribution, motivated by the availability of complementary descriptors, is a late fusion approach that automatically determines how to combine a large set of descriptors, giving a high increase in the average precision of detected concepts. All the proposed approaches are validated on the TRECVid challenge datasets which focus on visual concept detection in very large and uncontrolled multimedia content.
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Produção, qualidade e sanidade de frutos de bananeira 'BRS Conquista' ensacados com polipropileno de diferentes cores / Production, quality and sanitation of banana plants 'BRS Conquista' bagged with polipropilen of different colorsMartins, Rafaelly Calsavara 23 February 2018 (has links)
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Previous issue date: 2018-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A bananeira é a segunda fruta com maior volume comercializado no mundo. Pelo fato de ser uma fruta muito apreciada pelo consumidor brasileiro, nos últimos anos surgiram diversas tecnologias que auxiliam no cultivo da bananeira, principalmente relacionadas à qualidade dos frutos. Nesse contexto, o trabalho teve como objetivo avaliar a influência da coloração dos sacos plásticos empregados no ensacamento de cachos de bananeira ‘BRS Conquista’. Os tratamentos consistiram no uso de sacos de polietileno comerciais, nas cores branco, preto, vermelho e azul, além da testemunha (sem ensacamento). O delineamento experimental foi em blocos casualizados, com cinco tratamentos, quatro repetições e quatro plantas por parcela, totalizando 80 plantas. Avaliou-se a qualidade fitossanitária dos frutos, sendo o número de pontuações de danos causados por tripes da erupção e a porcentagem de área lesionada causada por antracnose, além das características físicas dos frutos, como massa do cacho, massa da ráquis, massa dos frutos, número de frutos por cacho, número de pencas por cacho, massa das pencas, número, comprimento e diâmetro de frutos da segunda penca, e as características físico-químicas dos frutos, como sólidos solúveis, acidez titulável, relação polpa/casca, índice de maturação e período de maturação. Verificou-se que os cachos que foram ensacados com sacos de coloração branca e preto apresentaram menor número de pontuações provocadas por tripes. Enquanto que para antracnose, os cachos que receberam sacos de coloração branca, vermelha e azul, apresentaram as menores porcentagens de área lesionada. O ensacamento dos cachos com sacos plásticos de diferentes colorações não interferiu nas variáveis produtivas. Contudo, nos cachos que não receberam ensacamento observaram-se maiores teores de sólidos solúveis que naquelas ensacadas. / Banana is the second most commercialized fruit crop in the world. Since it is very appreciated by the Brazilian consumer, in the last years, several technologies have come out to help in the development of the crop, mainly related to the quality of fruits. In this context, the objective of this work was to use banana bagging techniques for improvements in the banana cultivation process. Polyethylene bags of white, black, red, blue colors and the control (no bagging) were used in this technique. A randomized complete block design with five treatments, four replications, two plants per plot, totaling 80 plants was used. The evaluated characteristics in the post-harvest were the bunch mass, fruit mass, number of fruits per bunch, bunch number, second bunch mass, number of fruits of second batch, length, diameter, pH, soluble solids, titratable acidity, pulp/peel ratio, maturation index and maturation days. The phytosanitary quality of the fruits was evaluated, and the symptoms of thrips and anthracnose were assessed. In addition, the physical characteristics of the fruit, which is represented by the mass of the bunch, mass of the rachis, mass of the fruit, number of fruit per bunch, number of penca by bunch, productivity, mass of the second bunch, number of fruit in the second bunch, length and diameter of the fruit in the second bunch and physical chemical characteristics of the fruit, soluble solids, acidity, relation pulp/peel, index of maturation and period of maturation were evaluated. It was verified that for the variable mass of the second bunch, the white and black bags presented better results, whereas for pH variable the blue staining was the one which showed better results, and for the soluble solids it was the control group. This work showed that the efficiency of bagging is associated with the type and color of the bag which is used, since the coverings assign a thermal role inside the bunches / 130371/2016-5
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Performance of pulse-jet bag filter regarding particle removal for nano-waste incineration conditions / Performances d’un filtre à manche pour la capture de particules en conditions représentatives de l’incinération de nano-déchetsBoudhan, Rachid 05 July 2017 (has links)
Les performances de filtration d’un filtre à manche vis-à-vis de particules submicroniques et nanométriques ont été évaluées à l’échelle du laboratoire durant plusieurs cycles de colmatage/décolmatage. La distribution granulométrique des particules (aérosol de combustion) était représentative de celle rencontrée en incinération de nano-déchets en sortie de chambre de combustion à l’échelle du laboratoire. Le filtre à manche opérait en conditions réalistes, représentatives de celles rencontrées dans les lignes de traitement des fumées d’incinération de déchets en termes de température, humidité, vitesse de filtration, présence de réactifs et conditions de décolmatage. Le flux d’air et le filtre à manche étaient chauffés à 150°C, la teneur en eau était de 10-12% (soit 3% d’humidité relative HR), et la vitesse de filtration était fixée à 1,9 cm.s⁻¹. Un mélange de particules de taille submicronique de charbon actif et de bicarbonate de sodium, utilisées dans les lignes de traitement des fumées d’incinération pour l’abattement des dioxines/furanes et des gaz acides, était généré simultanément avec l’aérosol de combustion. L’étude s’est centrée sur les performances de filtration au début de la durée de vie du filtre à manche, avant stabilisation de la perte de charge résiduelle du filtre résultant des précédents cycles de filtration. La perte de charge maximale du filtre était fixée à 150 Pa pour tous les cycles de filtration avant décolmatage par rétro-soufflage à air comprimé. Les performances du filtre à manche ont été évaluées en termes d’évolution de sa perte de charge et de son efficacité de collecte (totale et fractionnelle) au cours des cycles de colmatage/décolmatage. De plus, des études expérimentales et théoriques ont été menées afin d’étudier l’influence de divers paramètres sur les performances de filtration du filtre en configuration manche ou plane, tels que l’humidité de l’air (3% HR versus 0% HR à 150°C), la température (150°C versus 24°C), la vitesse de filtration (1,9 cm.s⁻¹ versus 1,4 cm.s⁻¹) et l’influence de l’injection de réactifs. Les principaux résultats de cette étude sont : (i) importante efficacité de capture des particules du filtre à manche en conditions représentatives des lignes de traitement des fumées d’incinération : efficacité minimale de collecte de 98,5% mesurée pour des particules de taille 74 ± 15 nm (diamètre de mobilité électrique), (ii) influence du gâteau résiduel de particules au début de chaque cycle de filtration sur les performances de traitement, (iii) influence significative de l’humidité de l’air sur la structure du gâteau de particules probablement due à l’augmentation des forces d’adhésion entre les particules en présence d’humidité (150°C – 3% HR soit environ 100 g d’eau par kg d’air sec) ; augmentation plus rapide de la perte de charge du filtre à manche en présence d’humidité (150°C – 3% HR) qu’en conditions d’air sec (150°C – 0% HR). / Filtration performance of a pulse-jet bag filter was evaluated at the laboratory-scale regarding submicronic particles with a nanosized fraction during clogging/unclogging cycles. The particle size distribution was representative to those encountered at the outlet of a nano-waste incineration device at laboratory-scale. The bag filter was operated in conditions as similar as possible to those found in flue gas treatment of waste incineration plants, in terms of temperature, humidity, filtration velocity, injection of sorbent reagents and unclogging conditions. The air flow and the bag filter were heated to 150°C, the water content was maintained in the air flow in the range of 10-12% (3% of relative humidity RH), and filtration velocity throughout the bag filter was fixed at 1.9 cm.s⁻¹. A mixture of submicronic suspended particles of activated carbon and sodium bicarbonate, both used in flue gas treatment systems mainly for the removal of dioxins/furans and acid gases, was generated simultaneously with the aerosol representative of combustion emissions.The study focused on the filtration performance at the beginning of the bag filter’s lifetime filter for the 11 first clogging-unclogging cycles before stabilizing the residual pressure drop reached after pulse-jet unclogging. The maximum pressure drop was set at 150 Pa for all filtration cycles. Once the maximum pressure drop was reached, the filter was unclogged using the pulse-jet system. The performance of the bag filter was evaluated in terms of the evolution of pressure drop, fractional and total particle collection efficiencies, during the clogging/unclogging cycles.Moreover, an experimental and theoretical study was carried out on the influence of different parameters on the filtration performance of bag filter and flat filter, such as influence of humidity (3% RH versus 0% RH at 150°C), temperature (150°C versus 24°C), filtration velocity (1.9 cm.s⁻¹ versus 1.4 cm.s⁻¹) and the influence of the injection of sorbent reagents.The main results of this study are: (i) high collection efficiency of the bag filter in representative conditions of flue gas treatment of waste incineration: minimun particle collection efficiency of 98.5% for particle diameter of 74 ± 15 nm (electrical mobility diameter), (ii) influence of residual particle cake at the beginning of the filtration cycles on the bag filter performance, (iii) significant influence of humidity on the porosity of the particle cake due to the capillary condensation of water between the particles in presence of humidity (150°C - 3% RH i.e. almost 100 g of water per kg of dry air). Faster increase of bag filter pressure drop in presence of humidiy (150°C - 3% RH) as compared to the dry conditions (150°C - 0% RH).
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