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1

Leutwyler, Nicolás. „Flexible and Scalable methods for Formal Concept Analysis in Distributed Architectures“. Electronic Thesis or Diss., Université de Lorraine, 2024. http://www.theses.fr/2024LORR0112.

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Cette thèse explore l'adaptation de l'Analyse Formelle de Concepts (AFC) pour relever les défis posés par les environnements de données distribués et dynamiques. Cette recherche répond à la nécessité de techniques de fouille de données efficaces dans le contexte de l'Industrie 4.0 et de l'Internet des Objets (IoT), où la génération de données est vaste et continue. Les objectifs principaux incluent le développement de méthodes scalables et flexibles pour éviter la perte de concepts significatifs lors de la construction de réticulé de concepts, la proposition d'algorithmes incrémentaux adaptés aux flux de données en temps réel, et la démonstration des applications pratiques de ces méthodes. La thèse commence par une revue exhaustive de l'état de l'art, définissant les concepts clés de la représentation des connaissances, de la scalabilité et de l'AFC, en soulignant les défis inhérents à la gestion de grands ensembles de données et la nécessité de techniques de fouille de données efficaces. Une revue systématique de la littérature identifie les lacunes des méthodes d'AFC existantes, particulièrement celles applicables aux architectures distribuées, mettant en évidence la nécessité de nouvelles approches pour gérer la croissance exponentielle des concepts formels et la nature dynamique des flux de données. La thèse introduit des algorithmes novateurs pour la fusion des réticulés afin de récupérer des concepts potentiellement perdus et des méthodes incrémentales pour la construction de réticulé de concepts. Ces algorithmes, conçus pour des exécutions mono-thread et parallélisées, améliorent leur scalabilité et flexibilité. Des cas pratiques, comme un système de recommandation pour l'École de Ski Française, démontrent les avantages réels des méthodes proposées. Des évaluations empiriques utilisant des ensembles de données synthétiques et réels valident la performance de ces méthodes, montrant des améliorations significatives dans la gestion de données larges et distribuées. La thèse conclut en résumant les contributions et en suggérant des directions pour de futures recherches afin de renforcer les capacités de l'AFC dans les environnements distribués
This thesis explores adapting Formal Concept Analysis (FCA) to tackle challenges in distributed and dynamic data environments. This research addresses the need for efficient data mining techniques in Industry 4.0 and the Internet of Things (IoT), where data is vast and continuous. The primary goals include developing scalable, flexible methods to prevent the loss of significant concepts during concept lattice construction, proposing incremental algorithms for real-time data streams, and demonstrating practical applications of these methods. The thesis starts with a comprehensive review of current knowledge representation, scalability, and FCA, emphasizing the challenges of large datasets and efficient mining techniques. A systematic literature review identifies gaps in existing FCA methods, particularly for distributed architectures, highlighting the need for new approaches to manage the exponential growth of formal concepts and dynamic data streams. Novel algorithms are introduced for merging lattices to recover lost concepts and incremental methods for constructing concept lattices. These algorithms, designed for both single-threaded and parallel execution, enhance scalability and flexibility. Practical use cases, such as an e-commerce recommendation system for the French Ski School, demonstrate the real-world benefits of the proposed methods. Empirical evaluations using synthetic and real-world datasets validate the performance, showing significant improvements in handling large, distributed data. The thesis concludes by summarizing the contributions and suggesting future research directions to further enhance FCA capabilities in distributed settings
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Popescu, Adrian. „Structures conceptuelles pour la recherche d'images sur Internet“. Télécom Bretagne, 2008. http://www.theses.fr/2008TELB0093.

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La recherche d'images représente une partie importante du nombre total des requêtes sur Internet. Malgré leur utilité et leur popularité, les systèmes de recherche actuels souffrent de certaines limitations, comme le manque de sémantique dans le traitement des requêtes, l'imprécision des résultats, une faible interactivité, ou encore, un manque d'intégration de techniques de traitement d'images. Dans cette thèse, nous démontrons que l'exploitation de structures linguistiques à large échelle représente une réponse viable aux problèmes des systèmes actuels de recherche d'images. Cette thèse est constituée de trois parties : La première partie s'intéresse au cadre de notre étude. Pour commencer, nous essayons de répondre à la question " quelles images cherchons-nous ? " en étudiant un fichier de log qui met en évidence quelques domaines conceptuels importants en recherche d'images, comme les noms communs, les noms géographiques ou les personnalités. Ensuite, nous analysons la relation entre les concepts et leur représentation imagée, puis nous introduisons et définissons les structures linguistiques qui sont le cœur de notre approche. Nous concluons cette première partie par la proposition d'une architecture générique d'un système de recherche d'images intégrant des ressources sémantiques et des fonctionnalités de traitements d'images. La deuxième partie étudie la possibilité d'adapter et/ou de construire automatiquement des structures linguistiques à large échelle pour la recherche d'images sur Internet. Cette tâche est particulièrement ardue car il est nécessaire d'acquérir des connaissances de bonne qualité et d'assurer également une bonne couverture des domaines conceptuels analysés. Notre approche combine la réutilisation de ressources existantes, dans une forme adaptée à la recherche d'images et la structuration de nouvelles connaissances. Nous proposons par exemple un algorithme permettant une extraction totalement automatique d'un thésaurus géographique à partir de sources hétérogènes du Web. Nous proposons plusieurs évaluations permettant de valider notre approche. La troisième partie correspond à la dimension applicative de ce travail avec le développement de trois applications permettant le traitement de requêtes traitant des noms communs, des noms géographiques et des personnalités. Les architectures de ces applications sont des déclinaisons de notre architecture générique présentée dans la première partie. Elles intègrent les nouvelles ressources sémantiques que nous avons produites et proposent une recherche par le contenu dirigée par la sémantique. Ces applications sont décrites, illustrées, puis évaluées par rapport à des systèmes existants.
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3

Gratzmuller-Salamitou, Nicole. „Essai sur la représentation des connaissances en droit, structures conceptuelles“. Paris 1, 1986. http://www.theses.fr/1986PA010287.

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4

Covington, J. „Universal ultrahomogeneous structures“. Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376905.

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5

Aïmeur, Esma. „Metis : un systeme et une methode d'explication de taxinomies destinees a l'identification de structures conceptuelles“. Paris 6, 1994. http://www.theses.fr/1994PA066005.

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Dans les sciences d'observation telles que l'archeologie, la mineralogie ou la zoologie, de grandes quantites d'objets sont repertoriees sous forme de taxinomies et exprimees dans des catalogues au moyen d'un langage de description textuel, varie et nuance. La lourde gestion de ces catalogues et les problemes lies a la description et a la caracterisation des classes d'objets, ont fait naitre le besoin de construire d'une part une base de connaissances permettant d'integrer des informations coherentes, homogenes et non redondantes, d'autre part une structure de discrimination fiable, permettant de caracteriser les classes de maniere pertinente. Le principe d'explicitation des connaissances retenu dans le cadre de notre travail repose sur une approche incrementale. Notre systeme metis explicite progressivement les connaissances de l'expert et raffine le langage de description (appele modele structurel) a partir d'une suite de descriptions de classes qui lui sont presentees. Chaque nouvelle classe fournie au systeme, constitue un enrichissement et une nouvelle vision du modele de l'expertise, soit par specialisation d'une description deja acquise, soit par l'ajout d'une nouvelle description. Metis modifie ainsi dynamiquement le modele structurel des descriptions de classes explicitees. La taxinomie du domaine sert de fil conducteur pour guider le processus d'explicitation des connaissances. Elle est progressivement enrichie, permettant ainsi au systeme de presenter les traits discriminants et d'evaluer leur pertinence par apprentissage, ou avec le concours de l'expert
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6

Zhou, Chao Ying. „Effects of combination motions on cylinders in waves and currents“. Thesis, Imperial College London, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339445.

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7

Millán, Nebot Claudia Lucía. „Phase Combination and its Application to the Solution of Macromolecular Structures: Developing ALIXE and SHREDDER“. Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663022.

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Phasing X-ray data within the frame of the ARCIMBOLDO programs requires very accurate models and a sophisticated evaluation of the possible hypotheses. ARCIMBOLDO uses small fragments, that are placed with the maximum likelihood molecular replacement program Phaser, and are subject to density modification and autotracing with the program SHELXE. The software receives its name from the Italian painter Giuseppe Arcimboldo, who used to compose portraits out of common objects such as vegetables or flowers. Out of most possible arrangements of such objects, only a still-life will result, and just a few ones will truly produce a portrait. In a similar way, from all possible placements with small protein fragments, only a few will be correct and will allow to get the full “protein’s portrait”. The work presented in this thesis has explored new ways to exploit partial information and increase the signal in the process of phasing with fragments. This has been achieved through two main pieces of software, ALIXE and SHREDDER. With the spherical mode in ARCIMBOLDO_SHREDDER, the aim is to derive compact fragments starting from a distant homolog to our unknown protein of interest. Then, locations for these fragments are searched with Phaser. These include strategies for refining the fragments against the experimental data and giving them more degrees of freedom. With ALIXE, the aim is to combine information in reciprocal space from partial solutions, such as the ones produced by SHREDDER, and use the coherence between them to guide their merging and to increase the information content, so that the step of density modification and autotracing starts from a more complete solution. Even if partial solutions contain both correct and incorrect information, the combination of solutions that share some similarity will allow to get a better approximation to the correct structure. Both ARCIMBOLDO_SHREDDER and ALIXE have been used on test data for development and optimisation but also on datasets from previously unknown structures, which have been solved thanks to these programs. These programs are distributed through the website of the group but also through software suites of general use in the crystallographic community such as CCP4 and SBGrid.
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Cowtan, Kevin Douglas. „On the combination of small and macro molecule techniques for the phase refinement of macromolecular structures“. Thesis, University of York, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304262.

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9

Yavuzoglu, Asuman. „The Roles of Auditory Brainstem Structures in Analysis of Complex Sounds“. Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1290538894.

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10

Notaro, Anna. „Understanding the innovative viral glycosylation machinery using a combination of chemical and structural methodologies“. Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0125.

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The sujet de cette these portait sur la caractérisation de la machinerie originale utilisée par les Mimiviridae pour glycosyler les fibrilles entourant leurs capsides en travaillant sur les prototypes des 3 lignées connues, Mimivirus (A), Megavirus chilensis (B) et Moumouvirus australensis (C). Les fibrilles de Mimivirus sont décorées par 2 polysaccharides différents :l’un est caractérisé par la répétition d’un disaccaride linéaire fait de 3)-α-L-Rha-(1→3)-β-D-GlcNAc-(1→, avec un pyruvate branché en position 4,6 du GlcNAc ; l’autre présente une unité répétée branchée de séquence 2)-α-L-Rha-(1→3)-β-D-GlcNAc-(1→ pour le squelette linéaire et du rhamnose branché en position 3 par de 2OMeVioNAc. Nous avons suggéré que les fibrilles de Megavirus sont décorées par plus d'une espèce de polysaccharides/oligosaccharides, donc l’un ayant présentant un trisaccharide de RhaNAc:α-L-4OMe-RhaNAc-(1→3)-α-L-RhaNAc-(1→3)-α-L-RhaNAc-(1→. Les fibrilles de Moumouvirus sont décorées de glucosamine, quinovosamine et bacillosamine. A partir de ces données expérimentales il devenait possible de rechercher de nouveaux gènes responsables de ces glycosylations spécifiques. Le cluster de 9 gènes déjà publié de Mimivirus a pu être étendu à 13 gènes. Un cluster de 14 gènes a été d’autre part identifié dans le génome de Moumouvirus, le premier cluster de gènes de la glycosylation identifié dans la lignée B. Parmi les gènes de glycosylation, l’analyse fonctionnelle in vitro de la protéine L142 a permis de démontrer qu’il s’agit d’une N-acétyltransferase. En conclusion, les fibrilles des Mimiviridae sont lourdement glycosylées and le type de sucres et leur organisation dépend de la lignée considérée
The aim of this thesis is the study of the innovative glycosylation machinery used by the Mimiviridae family for the glycosylation of the fibrils sourrounding their capsid, using Mimivirus, Moumouvirus australensis and Megavirus chilensis as prototypes of lineages A, B and C, respectively. Mimivirus fibrils are decorated with two distinct polysaccharide: one is characterized by a linear disaccharide repeating unit made of 3)-α-L-Rha-(1→3)-α-D-GlcNAc-(1→, with a pyruvic acid branched at position 4,6 of GlcNAc.; the other has a branched repeating unit with the sequence 2)-α-L-Rha-(1→3)-β-D-GlcNAc-(1→ in the linear backbone and rhamnose further branched at position 3 by viosamine methylated at position 2 and acetylated at position 4. We suggested that Megavirus chiliensis fibrils are decorated by more than one polysaccharides/oligosaccharide species, one having this trisaccharide: α-L-4OMe-RhaNAc-(1→3)-α-L-RhaNAc-(1→3)-α-L-RhaNAc-(1→. Moumouvirus australensis fibrils are decorated with glucosamine and quinovosamine in addition to the rare sugar, bacillosamine. Starting from this experimental data, it was possible to identify new genes involved in glycosylation. As a result, the published nine-gene cluster of Mimivirus was extended to thirteen genes. A different cluster of fourteen genes was identified in Moumouvirus australensis, representing the first glycosylation gene cluster identified for the B lineage.Among the glycosylation genes, the function of L142 was investigated in vitro, demonstrating that it is an N-acetyltransferase. To conclude, the fibrils of Mimiviridae are heavily glycosylated and the type of sugars and their organization depends on their lineage
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11

Iyer, Ganesh R. „Role of intermetallics for both tin-lead and lead free solder structures and its solder pad combination“. Diss., Online access via UMI:, 2005.

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12

Schuth, Nils [Verfasser]. „Combination of advanced X-ray spectroscopy and quantum chemistry to determine electronic structures of metal-organic cofactors in proteins / Nils Schuth“. Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1177376563/34.

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13

Firat, Fatih Kursat. „Development Of Load And Resistance Factors For Reinforced Concrete Structures In Turkey“. Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608888/index.pdf.

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In this dissertation, a study is conducted to develop a probability based load and resistance factor design criterion for structural members considering the local conditions of Turkey. The Advanced First Order Second Moment (AFOSM) procedure is utilized as the probabilistic method of analysis. Various sources of uncertainties associated with concrete compressive strength, yielding and ultimate strength of reinforcing steel bars and the dimensions of beams, columns and shear walls are analyzed and quantified. The resistance statistics for different failure modes of different types of reinforced concrete structural members are computed by using the resistance parameters within the framework of reliability analysis. Structural load effects of dead, live, wind, snow and earthquake loads are analyzed considering the uncertainties in these loads. For different load combinations, the safety levels corresponding to the current design practice are evaluated in terms of the reliability indexes for reinforced concrete beam, column and shear wall design in flexure and shear, and also column design in combined action of flexure and axial load. Depending on this evaluation and the reliability index values reported from other countries, target reliability indexes are selected for different load combinations and different failure modes of structural members. Finally, a new set of load and resistance factors corresponding to selected target reliabilities and levels of uncertainties are proposed for each different failure modes of the structural members considered in this study, separately.
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14

Zaghlool, Baher SalahElDeen Othman Ahmed. „Behaviour of three-dimensional concrete structures under concurrent orthogonal seismic excitations“. Thesis, University of Canterbury. Civil Engineering, 2007. http://hdl.handle.net/10092/1177.

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This thesis is a study into the response and seismic safety of three-dimensional multi-storey concrete structures under concurrent orthogonal seismic excitations. It employs the nonlinear time-history method as its analysis tools. Time-history analyses rely heavily on their utilised earthquake records. Accordingly, this study examines the different approaches of selecting earthquake suites and develops a methodology of selecting representative earthquake scenarios. This methodology is credibly implemented in selecting a far- and a near field suites representative of the New Zealand seismic hazard. The study investigates the response of 6-, 9- and 12-storey concrete structures of different n-X-bays × m-Y-bays. Bidirectional responses of these considered structures are examined and consequently the current combination rules are scrutinised. Consequently this study strongly recommends the use of the 40-percent combination rule in lieu of the widely used 30-percent rule; and the use of time-history analysis in lieu of quasi/equivalent static and response modal analysis methods to avoid their strong dependence on combination rules. An intensive study is conducted employing the incremental dynamic analysis (IDA) technique to investigate structural demands of interstorey drifts, lateral storey drifts and storey accelerations. The study utilises the developed far-field suite and identifies the 50th and 90th percentile demands. Hence it provides easy-to-use expressions to facilitate rapid calculation of the structural demands and the effects of biaxial interactions. An implementation into the Demand and Capacity Factor Design (DCFD) format is presented that infers confidence in the performance levels of the considered structures. The study also draws attention to the importance of considering storey accelerations as their storey values reach as high as 10 × PGA. A sensitivity study is conducted by repeating the IDA investigation while using the developed near-field suite. Subsequently a comparison between the near- and the far-field results is conducted. The results were markedly similar albeit of less magnitudes until the (seismic hazard) intensity measure IM = Sa(T₁) = 0.4g when the near-field results show sudden flat large increase in demands suggesting a brittle collapse. This is attributed to the higher content of the higher mode frequencies contained in near-field ground motions. Finally, the study examines the (vectorial) radial horizontal shear demands in columns and beam-column joints of the previous far- and near-field studies. The combined radial shear demands in corner, edge and internal columns and joints are evaluated that roughly show a square-root proportional relationship with IM that exhibit somewhat brittle failure at IM ≥ 0.35g. Shears demands in the (4-way) internal columns and the (2-way) corner joints show highest magnitude in their respective class. The results suggest transverse joint shear reinforcement of 1.5, 1.0 and 0.5 of the longitudinal reinforcement of the neighbouring beam respectively for corner, edge and internal joints. An implementation of a proposed practical (and simpler) DCFD format shows satisfactory confidence in columns performance in shear up to IM = 0.35g, conversely to joints unsatisfactory performance in shear at the onset of inelastic behaviour (IM > 0.05g).
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15

Mohamed, Tahir Mohamed Ibrahim. „Combination of single crystal X-ray diffraction & ¹³C CP/MAS solid state NMR spectroscopy : studies of structures & dynamics of molecular organic crystals“. Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249427.

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16

Tabatabaei, Araghi Pedram. „Seismic analysis of concrete structures within nuclear industry“. Thesis, KTH, Betongbyggnad, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147215.

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Earthquake has always been a hazard for civil structures and keeping the structures integrity during and after an earthquake is of vital importance. This phenomenon’s impact is sudden and there is little or no warning to make the preparations for this natural disaster. Much damage has been done on structures which have led to major collapses and loss of many lives. Civil structures such as nuclear power plants are designed to withstand earthquakes and in the event of a major seismic event, to shut down safely. The aim of this thesis is to present the seismic design procedures for concrete structures, in basic and detailed design, according to Eurocode 8. Also to describe and understand the difference between Eurocode 8 and the DNB in seismic analysis of nuclear power plants. To evaluate the use of DNB instead of Eurocode 8 with Swedish seismic conditions is also another aim in this thesis.  Loads and actions which apply on a structure in a seismic design and corresponding load combinations are presented for Eurocode 8 and the DNB. An example is also given to clarify the design of primary seismic beams and columns with high ductility class (DCH). A case study of a nuclear structure from a test project named SMART2013 has been made by analyzing and comparing the results from Eurocode 8 and the DNB with a finite element model in FEM-Design software. Natural frequencies of the model are compared with the tested model in SMART2013-project to evaluate the finite element modeling. The model is seismically analyzed with load combinations from Eurocode 8 and the DNB with Swedish elastic ground response spectrum with the probability of 10-5. Results obtained from the primary seismic beams and columns are compared and analyzed.  Being on the safe and conservative side of the design values is always preferred in seismic analysis of a vital and sensitive structure such as nuclear power plants. The results from this thesis shows that, purely structural, combination of Swedish elastic ground response spectrum with the Eurocode 8 load combination will give more conservative values than the DNB.
I stora delar av världen har jordbävningar alltid varit ett hot för byggnaders integritet. Karaktären av en jordbävning är plötslig och föranleds av små eller inga varningar. Om jordbävningen medför att byggnader kollapsar sker ofta stora förluster av människoliv direkt eller indirekt. Kärnkraftsverk är anläggningar som dimensioneras för att klara jordbävningar och ska kunna gå till säker avställning vid en sådan händelse. Syftet med föreliggande rapport är att presentera hur betongkonstruktioner dimensioneras för jordbävning enligt Eurokod 8. Rapporten redogör även för skillnader mellan att dimensionera enligt Eurokod 8 och DNB (Dimensionering av nukleära byggnadskonstruktioner) samt hur det slår att använda Eurokod med svenska seismiska förhållanden. Laster och lastkombinationer som används vid jordbävningsdimensionering av betongbyggnader är presenterad enligt både Eurokod och DNB. Ett exempel presenteras för att visa hur primära balkar och pelare med hög duktilitetsklass (DCH) dimensioneras för seismisk påverkan. En fallstudie av en nukleär byggnad från ett internationellt projekt, SMART2013, har använts för att analysera och utvärdera resultaten från Eurokod och DNB. Byggnaden har analyserats med finita element med programvaran FEM Design. Modellens riktighet har verifierats genom att jämföra bland annat egenfrekvenser med de från officiella rapporter från SMART2013. Byggnaden är analyserad för seismisk last enligt svenska förhållanden med markresponsspektra 10-5, och primära balkar och pelare har analyserats och utvärderats enligt både Eurokod och DNB.
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Nguyen, Ngoc tan. „Évaluation non destructive des structures en béton armé : étude de la variabilité spatiale et de la combinaison des techniques“. Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0115/document.

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Les budgets alloués aux réparations des ouvrages et du patrimoine bâti ont atteint un niveau important. Une démarche scientifique est donc réfléchie pour réduire ces budgets par la mise en place d’outils visant à optimiser et fiabiliser le diagnostic structural des ouvrages. Les méthodes de contrôle non destructif (CND) constituent l’une des voies adaptées. Ces techniques reposent sur des principes physiques bien connus et les sociétés de service en proposent aujourd’hui un emploi courant, mais de nombreux verrous subsistent. Les deux besoins majeurs des gestionnaires d’ouvrages sont celui de l’optimisation de la stratégie de reconnaissance (où mesurer ? en combien de points ? avec quelle(s) techniques(s) et quelle précision ?) et celui de la quantification des propriétés mécaniques des matériaux ou des indicateurs de durabilité telles que la résistance à la compression, l’épaisseur carbonatée, le taux d’humidité. La question est comment déduire ces propriétés et ces indicateurs des mesures faites ? Et quelles sont la précision et la fiabilité de l’évaluation ?Cette thèse s’inscrit dans le cadre de deux projets nationaux de recherche : le projet ACDC-C2D2 et le projet ANR EvaDéOS. L’objectif principal est d’analyser la variabilité issue du CND pour ensuite remonter à la variabilité spatiale des bétons en conditions réelles. Les techniques de CND considérées sont choisies parmi les plus complémentaires : radar, résistivité électrique, ultrasons et rebond (scléromètre). Les résultats sont obtenus à partir d’une large campagne expérimentale effectuée sur des dalles d’un site test et sur deux ouvrages. L’analyse de la variabilité des CND a permis d’évaluer le nombre minimal de mesures nécessaire pour un niveau de confiance souhaité. D’autre part, la corrélation spatiale des données a été modélisée par l’analyse variographique. Les résultats montrent que, dans certain cas, les mesures de CND ne sont pas spatialement indépendantes. Les longueurs de corrélation identifiées dépendent de la propriété mesurée ainsi que du béton de l’ouvrage ausculté. La connaissance de ces longueurs de corrélation est un résultat nouveau qui permettra d’une part de mieux estimer la variabilité spatiale des bétons et d’autre part d’alimenter de manière plus réaliste les calculs fiabilistes des ouvrages. Elle permet également d’identifier un pas d’échantillonnage optimal sur ouvrage dans le cadre du suivi temporel ou pour effectuer des analyses complémentaires (ex. carottage, CND complémentaire ou plus fiable) et de représenter au mieux la cartographie spatiale des propriétés du béton.Dans le cadre du projet de recherche ANR EvaDéOS, les effets de la carbonatation et des gradients de teneur en eau (gradient d’humidité) sur les techniques CND ont été étudiés. Ce travail a pour objectifs d’étudier la sensibilité des techniques de CND à évaluer ces deux indicateurs de durabilité ainsi que leur impact sur la variabilité des mesures de CND. En laboratoire, des campagnes expérimentales ont été réalisées sur corps d’épreuve ayant différentes profondeurs de carbonatation ou des gradients d’humidité. L’effet de la carbonatation a été quantifié pour certains observables : résistivité électrique, vitesse ultrasonore et rebond. En ce qui concerne la variabilité des mesures de CND, l’effet de la carbonatation est seulement notable dans le cas du béton saturé, en particulier pour la variabilité locale de la résistivité électrique et du rebond. Cet effet reste faible par rapport à l’effet du degré de saturation. Les premiers résultats montrent également que les mesures de la résistivité électrique permettraient de suivre des gradients d’humidité dans le béton
The budgets assigned to the repair of structures and built heritage have reached an alarming level. A scientific approach is needed to reduce these budgets by implementing tools for a more reliable and optimal assessment of existing structures. Non-destructive testing (NDT) techniques constitute one of approaches adapted to real conditions. These techniques are based on well-known physical principles. Many companies offer their services in NDT domain today but many challenges remain. The two particular needs of structure managers are the optimization of the assessment strategy (where to measure? how many testing points? what technique(s) and what precision?) and the quantification of mechanical properties of materials or durability indicators such as the compressive strength, the carbonation depth, the moisture content. The questions are how to estimate these properties from measurements performed, and what are the accuracy and reliability of the evaluation?This thesis is part of two French research projects: ACDC-C2D2 and ANR EVaDéOS. The main objective is to analyze the variability of non-destructive testing (NDT) measurements for assessing the spatial variability of concrete in real conditions. NDT techniques considered are chosen as being complementary: radar, electrical resistivity, ultrasonic, rebound hammer. The results are obtained from a wide campaign of measurements, which was performed on concrete slabs of a testing site and on two existing structures. The analysis of the NDT variability makes it possible to assess the necessary minimum number of measurements for a desired level of confidence. Furthermore, the spatial correlation of the data was modeled using the variogram analysis. In some cases, the results show that NDT measurements are not spatially independent. The correlation lengths identified depend on the measured property and the concrete of the structure inspected. They are a new result, which will provide on one hand a better evaluation of spatial variability of concrete and on the other hand a more realistic input of reliability calculations of structures. The correlation length allows also the identification of an optimal sampling distance on existing structure within the monitoring time or the implementation of additional analyses (eg. core, complementary or more reliable NDT) and a better representation of the spatial mapping of concrete properties.Within the framework of the ANR EvaDéOS research project, the effects of carbonation and of moisture gradients on NDT measurements were studied. This work aims to study the sensitivity of NDT techniques for assessing these two durability indicators and their impact on the variability of NDT measurements. In laboratory, the experimental surveys were carried out on testing specimens having different depths of carbonation or moisture gradients. The effect of carbonation was quantified for several parameters: electrical resistivity, ultrasonic pulse velocity and rebound hammer. With respect to the variability of NDT measurements, the effect of carbonation is only significant in the case of saturated concrete, in particular for the local variability of electrical resistivity and rebound hammer. This effect is weak in comparison with the effect of saturation degree. The first results show also that the measurements of electrical resistivity would follow moisture gradients in concrete
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Gayraud, Fabrice. „Problème de tournées de véhicules avec contraintes de synchronisation dans le cadre de structures de maintien à domicile. Formalisation mathématique et hybridation à base de métaheuristique“. Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22591/document.

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Nous nous sommes intéressés à la problématique d’organisation des tournées de soins à domicile dans le cadre de structures de maintien à domicile comme par exemple les service d’Hospitalisation À Domicile ou les Services de Soins Infirmiers À Domicile. Les soins sont prodigués au domicile des patients par un ou deux soignants d’un type défini, comme médecin ou infirmier par exemple pendant une période de disponibilité du patient. Le patient est caractérisé par un niveau de dépendance et peut exprimer une préférence pour être soigné par un soignant plutôt qu’un autre. L’objectif est de construire les tournées des soignants en rendant visite à tous les patients tout en minimisant la longueur (ou durée) des tournées, en équilibrant les tournées suivant le niveau de dépendance des patients et en favorisant la préférence des patients. Après avoir réalisé un état de l’art des problèmes d’organisation de tournées de soins à domicile, nous proposons deux modélisations mathématiques de notre problème sous la forme d’un multiple Traveling Salesman Problem avec fenêtres de temps (m-TSPTW) auquel s’ajoute des contraintes spécifiques comme la synchronisation d’activités ou la prise en compte de types de ressource et des critères de performance propres au problème (équilibrage et préférence). Nous avons ensuite proposé des méthodes approchées basées sur des couplages métaheuristique - modèle de simulation testées sur des instances de la littérature d’un problème proche du nôtre et des instances adaptées à notre problème. Pour terminer, nous abordons trois perspectives de recherche :- la réorganisation des tournées suite à l’absence d’un soignant,- la prise en compte de temps de transport stochastique,- la localisation de structures de maintien à domicile et l’impact sur la construction des tournées
We are interested in a routing problem within the context of home health care. The cares are provided by one or two caregivers with the required type at the patient’s home during the patients’ availability. A type is doctor or nurse for instance. Each patient is characterized by a dependency level and may give a preference for a caregiver. The goal is to construct the tour for each caregiver visiting all patients, minimizing the length of the tours, balancing the workload of the caregivers and maximizing the satisfaction of the patients. We present a state of the art of the home health care problem. Then we propose two mathematical models of our problem based on the multiple Traveling Salesman Problem with Time Windows (m-TSPTW) with specific constraints like the activities’s synchronization or ressources’ type. The performance criteria are specific of our problem : workload balancing and patients’ satisfaction. We then propose approached methods based on combination between Metaheuristics and simulation model. This méthods have been tested on dataset from the literature and dataset adapted to our problem. We conclude with three research perspectives :- the reorganization of the tours when a caregiver is not available,- the integration of stochastic transport time,- the location of home support structure and its impact on the routes’ construction
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Boydens, Isabelle. „Evaluer et améliorer la qualité de l'information: herméneutique des bases de données administratives“. Doctoral thesis, Universite Libre de Bruxelles, 1998. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212039.

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Junior, Luiz Carlos Marcos Vieira. „Análise numérica do comportamento estrutural e da resistência de terças de aço restringidas pelas telhas“. Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-01102007-091559/.

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Terças e longarinas metálicas são geralmente projetadas no Brasil desconsiderando a interação com as telhas, ou seja, como barras isoladas, apesar da norma brasileira NBR 14762:2001 apresentar um procedimento de cálculo que leva em consideração tal interação (método do fator R). O comportamento estrutural do sistema terça-telha é complexo e a análise completa deve considerar a não-linearidade geométrica e física, bem como a influência do contato e da conexão terça-telha. Foram analisados modelos numéricos propostos na literatura e desenvolvido um modelo via método dos elementos finitos (MEF) que incorpora as não-linearidades e o contato terça-telha. O modelo foi calibrado com resultados experimentais e posteriormente foi realizada uma análise paramétrica, a qual permitiu gerar expressões que relacionam a força (vento de sucção) com os deslocamentos. Foi também analisada a viabilidade da aplicação do método da resistência direta (MRD) ao dimensionamento de terças restringidas pela telha, empregando o método das faixas finitas (MFF) para a análise de estabilidade elástica, em que a restrição promovida pela telha foi modelada por meio de vínculos elásticos na mesa conectada com a telha. Foram considerados dois casos de distribuição de tensões normais: (i) tensões oriundas somente da flexão e (ii) tensões oriundas da flexão e torção. Em ambos os casos o momento resistente apresentou diferenças relativamente elevadas em relação ao obtido pelo método do fator R, refletindo a necessidade de uma abordagem específica do método para o sistema terça-telha.
The structural behavior of purlin-sheeting system is complex and the complete analysis should consider the physical and geometrical nonlinearity, as well as the influence of the purlin-sheeting contact and connection. The brazilian code NBR 14762:2001 provides a design procedure to consider the interaction between a purlin or girt connected to the sheeting (factor R method). In Brazil purlins and girts are typically designed as isolated beams, without consideration for this purlin-sheeting combination. Numerical models proposed in the literature were analyzed and a finite element model (FEM) was developed considering nonlinearities and the contact between purlin and sheeting. The model was validated through experimental results and then implemented in a parametrical analysis. Expressions were generated using the parametrical results to relate the loading (wind uplift) to the displacements. The direct strength method (DSM) was analyzed to the designed of purlins restrained by sheeting. The finite strip method (FSM) was used for elastic buckling determination. The restraint applied to the sheeting was modeled using an elastic foundation on the flange connected to the sheeting. Two stress distributions were considered: (i) bending stresses and (ii) bending and warping stresses. In both cases the nominal flexural strength presented considerable differences compared to the factor R design method, reflecting the necessity of a specific study to evaluate the viability of the DSM approach for purlin design.
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Alwash, Maitham Fadhil Abbas. „Assessment of concrete strength in existing structures using nondestructive tests and cores : analysis of current methodology and recommendations for more reliable assessment“. Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0587/document.

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Pour évaluer la résistance mécanique du béton dans un ouvrage existant, la méthodologie courante combine des mesures non destructives (CND) comme le rebond ou/et la vitesse des ondes ultrasoniques avec la technique destructive (carottes) afin de produire une relation‘‘modèle de conversion” entre la résistance mécanique et les mesures CND. Le modèle de conversion est utilisé pour estimer la valeur locale de résistance mécanique à chaque emplacement de test en utilisant la valeur CND correspondante. Ensuite, on calcule les estimations de la résistance moyenne et/ou de l’écart-type de la résistance (variabilité de la résistance du béton). Cependant, la fiabilité d’estimation est toujours discutable en raison des incertitudes associées à l’évaluation de la résistance basée sur les mesures CND. Pour améliorer la fiabilité, les incertitudes doivent être réduites en spécifiant et en contrôlant leurs facteurs d’influence. Par conséquent, l’objectif de cette thèse est d’analyser la méthodologie d’évaluation courante afin de fournir des recommandations pratiques qui peuvent améliorer la fiabilité de l’évaluation de la résistance in-situ du béton dans les ouvrages existantes par des tests non destructifs et des carottes.Pour ce but, un simulateur a été construit afin d’analyser les effets des facteurs les plus influents en utilisant une vaste campagne de données provenant de sources différentes (études in situ ou en laboratoire et données synthétiques générées). La première contribution de ce travail est le développement d’une nouvelle approche d’identification du modèle ‘‘bi-objectif” qui peut efficacement capturer la variabilité de la résistance mécanique en plus de la moyenne. Après avoir étudié l’effet du mode de sélection des emplacements pour les carottes, une méthode a été proposée pour sélectionner ces emplacements en fonction des mesures CND ‘‘sélection conditionnelle” qui améliore la qualité de l’évaluation sans coût supplémentaire. Une dernière innovation est l’établissement de courbes de risque qui quantifient la relation entre le nombre de carottes et la précision de l’estimation. Enfin, des recommandations ont été formulées afin de fournir des estimations plus fiables
To assess concrete strength in an existing structure, the current methodology combines nondestructive measurements (NDT) like rebound hammer or/and pulse velocity with destructive technique (cores) in order to implement a relationship ‘‘conversion model” between the compressive strength and NDT measurements. The conversion model is used to estimate the local strength value at each test location using the corresponding NDT value.Then the estimated mean strength and/or estimated strength standard deviation (concrete strength variability) values are calculated. However, the reliability of these estimated values isalways a questionable issue because of the uncertainties associated with the strength assessment based upon NDT measurements. To improve the reliability, the uncertainties must be reduced by specifying and controlling their influencing factors. Therefore, the objective of this thesis is to analyze the current assessment methodology in order to provide practical recommendations that can improve the reliability of assessing the in-situ strength in existing concrete structures by nondestructive tests and cores.To this end, a simulator was built in order to analyze the effects of the most influencing factors using a large campaign of datasets from different sources (in-situ or laboratory studies,and generated synthetic data).The first contribution of this work is the development of a new model identification approach“bi-objective” that can efficiently capture the strength variability in addition to the mean strength. After studying the effect of the way of selection the core locations, a method was proposed to select these locations depending on the NDT measurements “conditional selection” that improves the quality of assessment without additional cost. A third innovation was the development of a procedure to identify the relation between the number of cores and the accuracy of the estimation. Finally recommendations were derived in order to providemore reliable estimated values
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Baságlia, Cilmar Donizeti. „Sobre o comportamento estrutural de terças de aço considerando a interação com as telhas“. Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-06042016-104944/.

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Nos últimos anos tem sido observada uma significativa redução do uso das telhas pesadas nas edificações industriais, como as telhas de fibrocimento, por exemplo, e a preferência por telhas mais leves e que permitem maior racionalização da construção, como as telhas metálicas (aço zincado e alumínio). Assim, a fixação por meio de ganchos foi naturalmente sendo substituída por parafusos auto-atarraxantes, permitindo uma elevada eficiência estrutural da interação terça-telha, portanto, as terças que eram tratadas como elementos estruturais independentes passaram a ser projetadas com base no comportamento conjunto com as telhas. Diante disso, este trabalho apresenta um estudo sobre o comportamento estrutural de terças de aço considerando a interação terça-telha, com ênfase na distorção lateral. Para tanto, são analisados os modelos teóricos encontrados na literatura e os procedimentos normativos, bem como são desenvolvidas análises numéricas de sistemas representativos de coberturas, via método dos elementos finitos (MEF), que incluem os efeitos da não-linearidade física e geométrica. Através destes modelos numéricos, validados por resultados experimentais de ensaios realizados na EESC-USP, é realizada uma avaliação da influência da rigidez à flexão da terça, da conexão telha-terça, do tipo de seção da terça e da presença e posicionamento de tirantes de travamento lateral das terças. Neste contexto, concluiu-se que as telhas, desde que fixadas adequadamente as terças, contribuem para a estabilidade lateral, impondo mecanismos de falha que diferem substancialmente dos mecanismos clássicos da teoria da estabilidade elástica.
Recent years have seen a significant reduction in the use of heavy sheeting such as fiber cement roof sheets in industrial buildings, and an increasing preference for lighter sheeting that allows for greater rationalization of the construction, such as metallic sheeting (zinc-coated and aluminum). Thus, fixing by means of hooks was naturally replaced by screws, allowing for high structural efficiency of the purlin-sheeting combination, and purlins, which heretofore had been treated as independent structural elements, began to be designed based on their combined behavior with sheeting. This paper discusses the findings of a comprehensive on the structural behaviour of steel purlins under wind uplift considering the purlin-sheeting combination, with emphasis on lateral distortional. To this end, an analysis is made of the theoretical models available in the literature and in standard procedures, and systems representative of roofs are analyzed numerically via the finite elements method (FEM), including the effects of physical and geometrical nonlinearity. Based on these numerical models, which are validated by the experimental results of tests conducted at School of Engineering of São Carlos - University of São Paulo, an evaluation is made of the influence of the purlin\'s flexural stiffness, the sheeting-purlin connection, the type of purlin section (channel and Z-sections), and the number of rows of bridging (bracing). In this context, it was concluded that sheeting, provided it is properly fixed to the purlins, contributes toward lateral stability, imposing failure modes that differ considerably from the classic mechanisms of the theory of elastic stability.
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Paleologos, Esther, und esther paleologos@rmit edu au. „An exploration of new processes and products for knitted textiles: this research will explore the combination of standard and non-standard fibres and finishing processes to create three-dimensional and sculptural knitted fabric structures, while expanding the potential of domestic machine knitting to be viewed as an art form“. RMIT University. Fashion & Textiles, 2010. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20100329.143129.

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Contemporary knitting over the past decade has experienced a recent resurgence in cultural interest and technical exploration. This research project aims to identify, through personal practice, the implications of knitting as undefined, removed from the boundaries of product. It is the dissolving of the lines between design, art and craft and exploring the domestically machine knitted textile via the use of materials and the inherent qualities of the fabric which are the driving factors of this research. It is through this exploration that my personal and creative process is diversified. The traditional connotations of knitting are historical, social and cultural, in particular hand knitting. Childhood memories of mothers and grandmothers knitting out of necessity, for clothing, often evoke feelings of safety, warmth and comfort. This familiarity of the looped stitches and understanding of the knit as garment binds knitting to fashion. Industrial knitting process, as scale of stitch is reduced, begins to remove this familiarity and creates an anonymity of structure and process, for example jersey knits used for t-shirts. This instant recognition for knitting as clothing is part of the design process where-by knitted fabrics work in unison with product. It is this boundary that has defined my professional practice designing for knitwear. This research involves a more experimental and fluid approach to producing the textile, considering the qualities and potential of the structure as something to celebrate in its own form. Designers such as Issey Miyake, Hussein Chalayan and the artist Rosmarie Trockel have been influential in taking fashion concepts into the gallery, often knitted. This movement of making conceptual and political statements, especially in the case of the industrially knitted pieces by Trockel, was a step to question the traditional and feminist perceptions of knitting and using the process as a material to create art. While these exhibitions explored the knitted textile in the form of fashion garment, the importance of diversifying the knitted cloth and displaying conceptual pieces is a major influence on this research. Also the more recent exhibition 'Radical Lace and Subversive Knitting', (Museum of Arts & Design New York 2007), has allowed for a reinvigorated forum for constructed textiles to be viewed as object, new product or purely as spatial explorations of structure. The impact of these ideas has allowed for the consideration of the textile being stripped back further and to remove the instant connot ation of product application. Exploration of materials, knitted structures and the manipulation of fabric without the constraints of identified product is the impetus of this project. The evolution of the outcomes is instrumental to the reactions of fibres, stitch and interplays of positive and negative space, while suggestions of product are accidental and created by the knitted form as it is removed from the machine. A personal interest in exploiting the knitted structures potential to possess transparency and opacity, become sculptural and changeable by hand have influenced the choices of material and stitch combination. This experimentation has informed my personal practice and the involved process of making.
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Fuster, Criado Laura. „Linear and nonlinear room compensation of audio rendering systems“. Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/59459.

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[EN] Common audio systems are designed with the intent of creating real and immersive scenarios that allow the user to experience a particular acoustic sensation that does not depend on the room he is perceiving the sound. However, acoustic devices and multichannel rendering systems working inside a room, can impair the global audio effect and thus the 3D spatial sound. In order to preserve the spatial sound characteristics of multichannel rendering techniques, adaptive filtering schemes are presented in this dissertation to compensate these electroacoustic effects and to achieve the immersive sensation of the desired acoustic system. Adaptive filtering offers a solution to the room equalization problem that is doubly interesting. First of all, it iteratively solves the room inversion problem, which can become computationally complex to obtain when direct methods are used. Secondly, the use of adaptive filters allows to follow the time-varying room conditions. In this regard, adaptive equalization (AE) filters try to cancel the echoes due to the room effects. In this work, we consider this problem and propose effective and robust linear schemes to solve this equalization problem by using adaptive filters. To do this, different adaptive filtering schemes are introduced in the AE context. These filtering schemes are based on three strategies previously introduced in the literature: the convex combination of filters, the biasing of the filter weights and the block-based filtering. More specifically, and motivated by the sparse nature of the acoustic impulse response and its corresponding optimal inverse filter, we introduce different adaptive equalization algorithms. In addition, since audio immersive systems usually require the use of multiple transducers, the multichannel adaptive equalization problem should be also taken into account when new single-channel approaches are presented, in the sense that they can be straightforwardly extended to the multichannel case. On the other hand, when dealing with audio devices, consideration must be given to the nonlinearities of the system in order to properly equalize the electroacoustic system. For that purpose, we propose a novel nonlinear filtered-x approach to compensate both room reverberation and nonlinear distortion with memory caused by the amplifier and loudspeaker devices. Finally, it is important to validate the algorithms proposed in a real-time implementation. Thus, some initial research results demonstrate that an adaptive equalizer can be used to compensate room distortions.
[ES] Los sistemas de audio actuales están diseñados con la idea de crear escenarios reales e inmersivos que permitan al usuario experimentar determinadas sensaciones acústicas que no dependan de la sala o situación donde se esté percibiendo el sonido. Sin embargo, los dispositivos acústicos y los sistemas multicanal funcionando dentro de salas, pueden perjudicar el efecto global sonoro y de esta forma, el sonido espacial 3D. Para poder preservar las características espaciales sonoras de los sistemas de reproducción multicanal, en esta tesis se presentan los esquemas de filtrado adaptativo para compensar dichos efectos electroacústicos y conseguir la sensación inmersiva del sistema sonoro deseado. El filtrado adaptativo ofrece una solución al problema de salas que es interesante por dos motivos. Por un lado, resuelve de forma iterativa el problema de inversión de salas, que puede llegar a ser computacionalmente costoso para los métodos de inversión directos existentes. Por otro lado, el uso de filtros adaptativos permite seguir las variaciones cambiantes de los efectos de la sala de escucha. A este respecto, los filtros de ecualización adaptativa (AE) intentan cancelar los ecos introducidos por la sala de escucha. En esta tesis se considera este problema y se proponen esquemas lineales efectivos y robustos para resolver el problema de ecualización mediante filtros adaptativos. Para conseguirlo, se introducen diferentes esquemas de filtrado adaptativo para AE. Estos esquemas de filtrado se basan en tres estrategias ya usadas en la literatura: la combinación convexa de filtros, el sesgado de los coeficientes del filtro y el filtrado basado en bloques. Más especificamente y motivado por la naturaleza dispersiva de las respuestas al impulso acústicas y de sus correspondientes filtros inversos óptimos, se presentan diversos algoritmos adaptativos de ecualización específicos. Además, ya que los sistemas de audio inmersivos requieren usar normalmente múltiples trasductores, se debe considerar también el problema de ecualización multicanal adaptativa cuando se diseñan nuevas estrategias de filtrado adaptativo para sistemas monocanal, ya que éstas deben ser fácilmente extrapolables al caso multicanal. Por otro lado, cuando se utilizan dispositivos acústicos, se debe considerar la existencia de no linearidades en el sistema elactroacústico, para poder ecualizarlo correctamente. Por este motivo, se propone un nuevo modelo no lineal de filtrado-x que compense a la vez la reverberación introducida por la sala y la distorsión no lineal con memoria provocada por el amplificador y el altavoz. Por último, es importante validar los algoritmos propuestos mediante implementaciones en tiempo real, para asegurarnos que pueden realizarse. Para ello, se presentan algunos resultados experimentales iniciales que muestran la idoneidad de la ecualización adaptativa en problemas de compensación de salas.
[CAT] Els sistemes d'àudio actuals es dissenyen amb l'objectiu de crear ambients reals i immersius que permeten a l'usuari experimentar una sensació acústica particular que no depèn de la sala on està percebent el so. No obstant això, els dispositius acústics i els sistemes de renderització multicanal treballant dins d'una sala poden arribar a modificar l'efecte global de l'àudio i per tant, l'efecte 3D del so a l'espai. Amb l'objectiu de conservar les característiques espacials del so obtingut amb tècniques de renderització multicanal, aquesta tesi doctoral presenta esquemes de filtrat adaptatiu per a compensar aquests efectes electroacústics i aconseguir una sensació immersiva del sistema acústic desitjat. El filtrat adaptatiu presenta una solució al problema d'equalització de sales que es interessant baix dos punts de vista. Per una banda, el filtrat adaptatiu resol de forma iterativa el problema inversió de sales, que pot arribar a ser molt complexe computacionalment quan s'utilitzen mètodes directes. Per altra banda, l'ús de filtres adaptatius permet fer un seguiment de les condicions canviants de la sala amb el temps. Més concretament, els filtres d'equalització adaptatius (EA) intenten cancel·lar els ecos produïts per la sala. A aquesta tesi, considerem aquest problema i proposem esquemes lineals efectius i robustos per a resoldre aquest problema d'equalització mitjançant filtres adaptatius. Per aconseguir-ho, diferent esquemes de filtrat adaptatiu es presenten dins del context del problema d'EA. Aquests esquemes de filtrat es basen en tres estratègies ja presentades a l'estat de l'art: la combinació convexa de filtres, el sesgat dels pesos del filtre i el filtrat basat en blocs. Més concretament, i motivat per la naturalesa dispersa de la resposta a l'impuls acústica i el corresponent filtre òptim invers, presentem diferents algorismes d'equalització adaptativa. A més a més, com que els sistemes d'àudio immersiu normalment requereixen l'ús de múltiples transductors, cal considerar també el problema d'equalització adaptativa multicanal quan es presenten noves solucions de canal simple, ja que aquestes s'han de poder estendre fàcilment al cas multicanal. Un altre aspecte a considerar quan es treballa amb dispositius d'àudio és el de les no linealitats del sistema a l'hora d'equalitzar correctament el sistema electroacústic. Amb aquest objectiu, a aquesta tesi es proposa una nova tècnica basada en filtrat-x no lineal, per a compensar tant la reverberació de la sala com la distorsió no lineal amb memòria introduïda per l'amplificador i els altaveus. Per últim, és important validar la implementació en temps real dels algorismes proposats. Amb aquest objectiu, alguns resultats inicials demostren la idoneïtat de l'equalització adaptativa en problemes de compensació de sales.
Fuster Criado, L. (2015). Linear and nonlinear room compensation of audio rendering systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59459
TESIS
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Mondal, Kartick Chandra. „Algorithmes pour la fouille de données et la bio-informatique“. Thesis, Nice, 2013. http://www.theses.fr/2013NICE4049.

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L'extraction de règles d'association et de bi-clusters sont deux techniques de fouille de données complémentaires majeures, notamment pour l'intégration de connaissances. Ces techniques sont utilisées dans de nombreux domaines, mais aucune approche permettant de les unifier n'a été proposée. Hors, réaliser ces extractions indépendamment pose les problèmes des ressources nécessaires (mémoire, temps d'exécution et accès aux données) et de l'unification des résultats. Nous proposons une approche originale pour extraire différentes catégories de modèles de connaissances tout en utilisant un minimum de ressources. Cette approche est basée sur la théorie des ensembles fermés et utilise une nouvelle structure de données pour extraire des représentations conceptuelles minimales de règles d'association, bi-clusters et règles de classification. Ces modèles étendent les règles d'association et de classification et les bi-clusters classiques, les listes d'objets supportant chaque modèle et les relations hiérarchiques entre modèles étant également extraits. Cette approche a été appliquée pour l'analyse de données d'interaction protéomiques entre le virus VIH-1 et l'homme. L'analyse de ces interactions entre espèces est un défi majeur récent en bio-informatique. Plusieurs bases de données intégrant des informations hétérogènes sur les interactions et des connaissances biologiques sur les protéines ont été construites. Les résultats expérimentaux montrent que l'approche proposée peut traiter efficacement ces bases de données et que les modèles conceptuels extraits peuvent aider à la compréhension et à l'analyse de la nature des relations entre les protéines interagissant
Knowledge pattern extraction is one of the major topics in the data mining and background knowledge integration domains. Out of several data mining techniques, association rule mining and bi-clustering are two major complementary tasks for these topics. These tasks gained much importance in many domains in recent years. However, no approach was proposed to perform them in one process. This poses the problems of resources required (memory, execution times and data accesses) to perform independent extractions and of the unification of the different results. We propose an original approach for extracting different categories of knowledge patterns while using minimum resources. This approach is based on the frequent closed patterns theoretical framework and uses a novel suffix-tree based data structure to extract conceptual minimal representations of association rules, bi-clusters and classification rules. These patterns extend the classical frameworks of association and classification rules, and bi-clusters as data objects supporting each pattern and hierarchical relationships between patterns are also extracted. This approach was applied to the analysis of HIV-1 and human protein-protein interaction data. Analyzing such inter-species protein interactions is a recent major challenge in computational biology. Databases integrating heterogeneous interaction information and biological background knowledge on proteins have been constructed. Experimental results show that the proposed approach can efficiently process these databases and that extracted conceptual patterns can help the understanding and analysis of the nature of relationships between interacting proteins
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Gagné, Réjean. „Structures conceptuelles techno-scientifiques dans un environnement de formation technique /“. 2004. http://proquest.umi.com/pqdweb?did=813771301&sid=16&Fmt=2&clientId=9268&RQT=309&VName=PQD.

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Lubin, Leslie. „Étude des métaphores conceptuelles utilisées dans la description des structures anatomiques“. Thèse, 2005. http://hdl.handle.net/1866/17663.

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Stefan, TKAC, und 史帝芬. „THE COMBINATION OF TENSILE AND WOODEN STRUCTURES“. Thesis, 2011. http://ndltd.ncl.edu.tw/handle/58358154865066077044.

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碩士
中華大學
建築與都市計畫學系碩士班
99
Abstract In this master diploma project two hi – tech fields of civil engineering and architecture are discussed. As the combination of tensile structures and modern wooden constructions became an important issue if talking about large scale sustainable green design applications in nowadays era of micro and nano hi – technology demands of architecture, there are still not many referential and educational materials in this field. This final master design thesis may serve as a brief recherche in this field of architecture and also as a design anticipating possible progression in hi - tech applications. Work consists of two major parts, first one, the theoretical, serves as an introduction by gathering all the necessary information about the mentioned issue, counting in types, divisions, materials and statics of the two selected constructional fields. It also evaluates and compares them, showing positives as well as negatives of each example. At the end of each chapter in theoretical part a visual gallery of examples that are acting as a demonstration of current practical use of constructions that are discussed is provided. Practical part, contains mostly design drawings made for the selected competition, applied as a master diploma project, presenting architecture and urban renewal design project of an old swimming pool in the city of Košice, Slovak republic, EU. This project is also shown as an example proposal to demonstrate the application of a possible constructional combination solution with the elements mentioned in the theoretical part
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Tseng, Lin-Wen, und 曾琳文. „Weighted Combination Association Analysis of Pedigree Data with Different Families Structures“. Thesis, 2011. http://ndltd.ncl.edu.tw/handle/32089143016000687934.

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碩士
輔仁大學
應用統計學研究所
99
The aim of genetic association analysis is to identify the extent of association between a genetic marker and a disease. Because pedigree data contain more association information than familial data, use of pedigree data to develop association tests has received attention in this area. The previously developed pedigree association methods had used information of familial data structures of case-control groups, concordant-discordant sib-pairs and case-parent triads generated from pedigrees. However, tetrad families have not been considered. In this thesis, pedigree association tests developed by incorporating case-parent tetrad families are proposed. Several weighted combined test statistics, which combine information of case-control groups, concordant-discordant sib-pairs, triad families and tetrad families, are investigated. Simulation studies indicate that incorporation of tetrad families does enhance the testing power in genetic association analysis.
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Hung, Po-Cheng, und 洪柏政. „Using Sentence Pattern Combination Game to Improve Sixth Graders’ Ability of English Sentence Structures“. Thesis, 2016. http://ndltd.ncl.edu.tw/handle/85556709665961210508.

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碩士
文藻外語大學
外語文教事業發展研究所
104
In order to help the sixth graders understand the basic sentence structures and help students learn sentence structures via a joyful, exciting, and intense teaching game, the researcher designed the Sentence Pattern Combination Game. This game was designed based on five basic sentence patterns. The students learned the sentence structures and knew how to disassemble the basic structures of the sentences through playing the Sentence Pattern Combination Game. The researcher selected one class of 32 6th graders from a public school in northern Taiwan as the participants. The study lasted for four weeks, with 3 forty-minute classes per week. This study was employed a single group research design. Before the program, students were asked to take the pre-test about the structures of the English sentences. During the intervention, students followed the game rules to learn five basic sentence pattern structures. After the program, students were asked take the posttest about the sentence structures of all five basic sentence patterns to make sure the learning outcome. The data collection involved the pretest and posttest of the program. The test contents were about 1) recognizing sentence components and 2) analyzing English sentence structures. After collecting the data, the data were analyzed by a paired sample t-test.
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Warren, Walker Lloyd. „Efficient data structures for modelling the combination of three-dimensional DTM and CAS data“. Thesis, 1999. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/164921.

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"The overall aim of this research is to develop efficient data structures, algorithms and techniques that can be used to model the combination of artificial structures and realistic terrain."
Doctor of Philosophy
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Sun, Cheng-Hao, und 孫成浩. „3D-confinement Tailored Hierarchical Structures through a Combination of Self-assembly and Micro-emulsion“. Thesis, 2019. http://ndltd.ncl.edu.tw/handle/jy7xv5.

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碩士
國立中央大學
化學工程與材料工程學系
107
Under 3D confinement generated through a micro-emulsion approach, block copolymer (BCP) tends to form micro spheres with onion-like nanodomains, ellipsoids with axially-stacked nanolamellae, and Oblate particles with nanocylinders. Such hierarchical (structure-within-structure) structures have potential applications in many fields, including biomedicine, energy, catalyst and optical devices. For the micro Emulsion approach, two immiscible solvents, chloroform and water, with different surface properties were used to produce BCP microstructures. PS-b-P4VP was dissolved in chloroform followed by the addition of a large amount of water with surfactant CTAB. In the presence of CTAB, the solution of PS-b-P4VP/chloroform was emulsified to form colloidal microparicles in the mixture after adding water. Upon removal of chloroform and water, PS-b-P4VP spontaneously self-assembled to form nanodomains within the microparicles. Under 3D confinement, self-assembly of PS-b-P4VP produced several structure-within-structure morphologies, which could by tailored by controls over molecular weight, solvent quality, as well as the surface energy of BCPs. As a result, onion-like, convex-concavo, and convex-convex microparticles or oblate mciroparticles with hexagonal arrays of nanopores were obtained. The hierarchical structures were then used as templates to fabricate carbon and metal materials with replicated morphologies for oxygen reduction reactions.
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Taoyi, Yu. „Combination of non-destructive tests for surface and in depth location of decay in timber structures“. Master's thesis, 2017. http://hdl.handle.net/1822/54646.

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Dissertação de mestrado em Structural Analysis of Monuments and Historical Constructions
As the increase of the rehabilitation market to the historical timber constructions, research topics on timber structures have been increasing recently. However, on earlier researches, topics were more focused on new timber constructions, but existing timber structures still remains an extremely important object of research, especially regards of its historical and aesthetic values. Non-destructive tests have shown their advantages of maintaining the integrity of the structures, yet the complexity for interpreting their results increases especially when decay is presented in the tested element. Hence, the influence of surface and in-depth decay on the timber properties and on the nondestructive test results were analysed in this dissertation. Non-destructive tests (Pilodyn®, Resistograph®, ultrasound test, acoustic emission test) and mechanical tests (density and bending test) were applied on three dismantled elements from a roof truss of an old building. Results were then compared with the defect map and visual grade which were generated based on a preliminary visual inspection. A general idea of how the defects (knot, fungi attack, insect attack, ringshake) influenced the test values were summarized. Furthermore, linear correlation and multiple regression models between non-destructive test results and the physical and mechanical properties were built. Specific attention was paid to the influence of segment size and the presence of decay. Finally, a methodology of how to interpret the onsite timber assessment data was proposed, and applied to a timber roof truss from an old timber building. The work presented in this dissertation was carried out at the Civil Engineering Department of University of Minho, Portugal.
Com o aumento do mercado de reabilitação em construções antigas de madeira, os tópicos de pesquisa sobre estruturas de madeira aumentaram recentemente. No entanto, verifica-se que nas pesquisas anteriores, os tópicos foram mais focados em construções novas de madeira, mas as estruturas existentes ainda são um objeto de pesquisa extremamente importante, especialmente quando se trata de edifícios de valor patrimonial histórico e social. Os testes não destrutivos têm mostrado suas vantagens em relação a manter a integridade das estruturas e elementos, mas a complexidade para interpretar os seus resultados aumenta especialmente quando existe degradação no elemento testado. Dessa forma, a influência da degradação superficial e em profundidade nas propriedades da madeira e nos resultados dos testes não-destrutivos foi analisada nesta tese. Testes não-destrutivos (Pilodyn®, Resistograph®, teste de ultrassons, teste de emissão acústica) e testes mecânicos (densidade e flexão) foram aplicados em três elementos retirados de uma estrutura de telhado em um antigo edifício. Os resultados foram então comparados com um mapa de defeitos e a classe visual que foram obtidos com base numa inspeção visual inicial. Análises globais de como os defeitos (nós, ataque de fungos, ataque de insetos, fissuras) influenciaram os valores de teste foram resumidas. Além disso, foram construídos modelos de correlação linear e de regressão múltipla entre resultados de testes não-destrutivos e as propriedades físicas e mecânicas. Foi dada especial atenção à influência da dimensão do segmento e à presença de degradação. Por fim, foi proposta uma metodologia de como interpretar os dados de avaliação de madeira, e aplicada a uma cobertura de madeira um antigo edifício. O trabalho apresentado nesta tese foi realizado no Departamento de Engenharia Civil da Universidade do Minho, em Portugal.
木结构建筑在世界各地都有广泛且悠久的应用,很多现存木结构历史建筑都具有重要的文化和历史价值。 近年来,由于木结构修复市场的增长,关于木材以及木结构的研究数量也大量增长。但值得注意的是,以 往的研究大多注重对于新木材的评估,而对于古木材的评估和研究仍旧是一个重要的课题。 木材的无损测试,虽然能够保证检测对象的完整性,但由于木材的复杂特性,其能提供的信息在一定程度 上是有限的。而对于古木材,由于腐朽、虫害、菌害的存在,采用无损测试对木材进行评估的复杂性进一 步增加。 本文中,对三个从某古建筑的屋顶桁架上取下的木试件进行了无损测试(Pilodyn®,Resistograph®,超 声波测试,声发射测试)和有损试验(密度测试,弯曲测试)。测试的结果与前期目检得到的木材损伤图 及目检等级进行了比对,从而总结出各种损害对于试验结果的影响。 根据无损和有损试验的结构,采用了线性模型以及多元回归分析以得出无损检测对于木材密度和抗弯刚 度的预测能力。并且,分析了不同的视觉等级下,不同的试件尺寸下,以及不同的损害种类下,预测能力 的变化。 最终,根据所得结果,提出了一个针对已损害木材的评估的方法,并对应用到一个古建筑上的屋顶桁架分 析。 本研究生论文完成于葡萄牙米尼奥大学土木工程学院。
Foundation for Science and Technology (FCT) - within the scope of the project PTDC/ECM-EST/1072/2014 is greatly acknowledged
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Li-JuanHuang und 黃莉娟. „Combination of β-elimination and High Resolution mass spectrometry for the determination of O-glycosylation sites and structures“. Thesis, 2012. http://ndltd.ncl.edu.tw/handle/2v556u.

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碩士
國立成功大學
化學系碩博士班
100
Altered protein O-glycosylation is known to associate with many human diseases. Studying protein O-glycosylaion, however, is difficult due to the lack of analytical methods. Compared to N-glycosylation, analyzing O-glycosylation site and structure is more challenging since there is no consensus sequence to predict its binding sites, no universal or specific enzymes to break O-glycans from the protein backbone; and it is hard to digest due to the high O-glycan binding density along a short sequence. In this study, we combine β elimination to cleave O-glycans from the peptide backbone and non-specific proteinase K to digest the cleaved peptides for analyzing O-glycosylation sites through mass mapping via LC-MSMS analysis. The intact protein without O-glycan release is also digested and analyzed by LC-MSMS for comparison. Based on the retention time matchings, potential O-glycosylation sites can be deduced from the β-eliminated peptides and further confirmed by the corresponding intact mass. The glycan structure can be identified by MSMS spectra of the intact peptide via either CID or ETD. Using fetuin, a O-glycosylated protein, as a model, we show all the known glycosylation sites, S271,T281,S282,S296,S341, can be successfully identified and their glycan structures can be unambiguously identified by the characteristic fragments such as 291(SA), 365(GalNAc+Gal), 657(GalNAc+Gal+ SA) detected via CID. Furthermore, the data indicate that β-elimination can lead to O-glycan eliminated peptides without extreme hydrolysis. Our preliminary data show that the developed method can be applied to identify unknown O-glycosylation sites and structure.
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Lin, Chih-Chang, und 林志昌. „Comparison of Voltage-Mode High-Order OTA-C Universal Filter Structures Using Weighting Signal and Linear Combination Approaches“. Thesis, 2004. http://ndltd.ncl.edu.tw/handle/8dak7n.

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碩士
中原大學
電機工程研究所
92
Many Operational Transconductance Amplifier (OTA)-based nth-order voltage-mode universal filter structures were proposed. Very recently, both linear combination and singnal weighting approaches archieve two new nth-order voltage-mode universal filter structures. The former employs 2n+4 single-input OTAs and n grounded capacitors. The latter employs 2n+2 single-input OTAs and n grounded capacitors. In this study, we have done the comparison between linear combination and weighting signal approaches in terms of filtering performance, noise, sensitivity, component spread and cascadability. H-spice simulations with UMC05 Level 49 parameters are used to do the comparison. When non-ideal active devices are considered, differences in frequency responses of the linear combination and weighting signal approaches will be observed. Clearly these differences can be attributed to non-ideal active devices. In the research of OTA-C filters, weighting signal approach is better than linear combination method in terms of filtering performance, noise and sensitivity because the signal weighting method uses two fewer single-ended-input OTAs than the linear combination approach. As we know, for the universal nth-order, the number of capacitors needed should be at least n and to achieve the independent tunability of each coefficient at least 2n+2 OTAs are required. In this sense our technique needs the fewest element, which should be very important for integration. In terms of component spread and cascadability, linear combination method is better than weighting signal approach. This is because the signal weighting method have more input path than linear combination approach. This paper offers the signal weighting and linear combination approaches differences in terms of filtering performance, noise, sensitivity, component spread and cascadability. We have to make the most of this comparsion’s conclusions, which should be very useful for filters implemented using linear combination and singnal weighting approaches archieve nth-order voltage-mode universal filter structures.
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Li, Po-Cheng, und 李博丞. „Self-Assembled Structures from PEGylated Polypeptide Block Copolymers Synthesized Using a Combination of ATRP, ROP, and Click Chemistry“. Thesis, 2014. http://ndltd.ncl.edu.tw/handle/21127408871948857995.

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碩士
國立中山大學
材料與光電科學學系研究所
102
In this study, we used a combination of atom transfer radical polymerization, ring opening polymerization, and click chemistry to synthesize new PEGylated polypeptide block copolymers of polystyrene-b-poly(γ-propargyl-L-glutamate-g- 2-(2-methoxyethoxy)ethyl) [PS-b-(PPLG-g-MEO2)]. We employed FTIR and WAXD to determine the secondary structures of the α-helical conformations of these PEGylated polypeptide block copolymers in the solid state, and circular dichroism spectroscopy to characterize them in solution. Hierarchical self-assembly of the PS-b-(PPLG-g-MEO2) diblock copolymers in the bulk state (characterized using WAXD, SAXS, and TEM) led to the formation of lamellar structures as a result of microphase separation of the diblock copolymers; the hexagonal cylinder packing nanostructure featured α-helical conformations of PEGylated polypeptide segments, which were oriented perpendicular to the director of the lamellar structure formed by the diblock copolymers. We obtained a range of micellar structures from the PS-b-(PPLG-g-MEO2) diblock copolymer in DMF (common solvent) upon the addition of selective solvents (H2O or MeCN). We observed only spherical micelles from the PS-b- (PPLG-g-MEO2) diblock copolymer in DMF/MeCN systems at all MeCN compositions. The micelle structures changed, however, from spherical structures to long wormlike, vesicle, and large compound micelles in the DMF/H2O system upon increasing the content of water. These different morphology transformations arose as a result of very different PS–solvent (H2O or MeCN) interaction parameters.
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37

Chuang, Tai-Jung, und 莊岱融. „Combination of Circular PDMS Mold and Gasbag Roller to Replicate Micro/Nano Structures of UV Resin on PC Film“. Thesis, 2011. http://ndltd.ncl.edu.tw/handle/48473209443419909031.

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碩士
國立臺灣大學
機械工程學研究所
99
Replicating microstructure by roller imprinting is one of the most effective methods to produce the components with nano micro-structures on surface. However, there are two challenges: how to better prepare the roller mold and how to increase the contact area between roller and substrate. The contact between the rigid roller and the substrate is nearly a line; the brief contact prevent perfect replication at high rolling speed. On the other hand, the conventional method producing the microstructure on the roller mold is done by wrapping the electroplated Ni mold on the roller. Warp and deformation of mold easily occur during rolling imprinting. In this research, a circular PDMS (polydimethylsiloxane) mold and a gasbag-roller imprinting facility are developed. The gasbag with controlled inner gas pressure is employed to sustain the circular PDMS flexible mold with microstructure. When a external pressure is applied on the shaft of gasbag-roller, the contact area between the roller and the substrate has been increased significantly from original line contact to area contact. This allows ample contact area and time between a gasbag-roller and substrate for the micro-structures on the mold to be completely replicated and cured. With aid of pressure sensitive films, it is discovered that the combination of the gasbag-roller and the PDMS mold not only increases the contact area between roller and substrate, but also enhances the contact pressure over the contact area. The quality and speed of replication thus can be greatly improved. A V-cut microstructure has been fabricated on the circular PDMS mold by micro-casting, and used for the gasbag-roller sustained circular PDMS mold. Experimental result show that over a large operational window of inner gas and external pressures the replication can be perfect. The imprinting facility and process have been employed to replicate AAO nanostructures on the PC film for antireflection and hydrophobic effect. The reflection has been droped from 9% in the bare PC film to 6% in the PC film with AAO nanostructures. The contact angle has increase from 86.4 o in the bare PC film to 108.1o in the PC film with AAO nanostructures. Fresnel microstructures are also replicated for the function of light-focusing. The light intensity has increased threefold as measured by the optical power meter. The results prove that an effective replication facility and process has been developed for fast and effective replication of micro- and nano-structures.
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38

Lee, Yu-chi, und 李育綺. „Hierarchical Structures of P(S-b-4VP) Thin Films Fabricated through a Combination of Solvent Annealing and Micro-Contact Imprinting“. Thesis, 2012. http://ndltd.ncl.edu.tw/handle/06166868193019889726.

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博士
國立中央大學
化學工程與材料工程研究所
100
We studied the self-assembly of block copolymer thin films with a combination of micro-contact imprinting and solvent annealing. Patterned substrates were prepared by selectively grafting PS chains on SiOx/Si by micro-contact imprinting. The PS-grafted regions have a hexagonal array on SiOx/Si. After spin coating on the patterned substrates, the block copolymer would selectively wet the PS-grafted regions with solvent vapor exposure. Therefore, solvent annealing causes dewetting-induced microdroplets with a microscopic order defined by the pattern of PS-grafted substrates. In this thesis, we investigated how relief polystyrene-block-poly(4-vinylpyridine), (P(S-b-4VP)) microstructures effected the internal nanostructures and microscopic shape on PS-patterned substrates in response to the solvent vapor selectivity. Upon annealing in THF vapor, the droplets comprised of nanospheres and the shape of each droplet is hemispherical cap. Solvent annealing in chloroform and acetone vapors led to terraced stack of lamellae. Each lamellar layer has the thickness of an entire PS-P4VP/P4VP-PS layer. In a dynamic process of DMF vapor annealing, the droplets would transform into three types of microstructures. They are nanosphere-comprised terraces, nanolamella-comprised terraces and nanocylinder-comprised droplets. For DMF annealed terraces, lamellar layers comprise PS-P4VP layer indicated that the thickness of PS-P4VP layer is half of the thickness of an entire PS-P4VP/P4VP-PS layer. The changes in nanoscale and microscale structures are due to the adaption of stimuli-responsive polymer materials to the free surface under the confinement of the patterned substrates. Finally, the movement of relief microstructures on a 30°-inclined patterned substrate was found to depend on the solvent solubility and internal nanostructures.
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39

Lee, Yun-Heng, und 李昀珩. „Combination of Circular PDMS Mold and Gasbag Roller to Replicate Continuous Anodic Aluminum Oxide Nano Structures by UV Resin on PC Film“. Thesis, 2012. http://ndltd.ncl.edu.tw/handle/12356512149650860549.

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碩士
國立臺灣大學
機械工程學研究所
100
Nanostructured thin films have been widely applied for anti-reflective components, bio-sensing and self-cleaning surfaces. The roller molds for production of nanostructured films mostly are made by expensive processes, such as e-beam or focused ion beam, or by wrapping the electroplated mold on the roller. Cost and complication are problems. Furthermore, the contact between the rigid roller and the substrate is nearly a line; the brief contact prevent perfect replication at high rolling speed. This study develops an effective, fast, and low-cost method to fabricate seamless anodic aluminum oxide (AAO) roller mold. Circular PDMS (polydimethylsiloxane) mold with nanostructures is then cast from the AAO roller mold and used as the mold. A facility combining UV-based imprinting technique, gasbag-roller and circular PDMS mold, has been designed and implemented to replicate nanostructures on the surface of polycarbonate (PC) continuously. The gasbag-roller is employed to increase the contact area and to ensure the conformity of contact between the mold and the substrate. The AAO roller mold is made by 2-step anodization process from a 99.9% purity circular aluminum tube, and the nano-pores are fabricated in the internal wall of the tube. The outer and inner diameters are 66mm and 60mm respectively, and the length is 50mm. The SEM photos show that the fabricated nanopores are similar as observed from all degrees of the surface.The alumina oxide membranes with nanopores of 220 nm and 430 nm in pitch and 160nm and 230nm in nanopore size are fabricated with anodization voltages of 80 V and 180 V, respectively. Nano pillars have been fabricated on the surface of circular PDMS mold by micro-casting. The circular PDMS mold with nanostructures is sustained by a gasbag roller. With aid of pressure sensitive films, it is verified that the combination of the gasbag-roller and the PDMS mold not only increases the contact area between roller and substrate, but also enhances the pressure uniformity over the contact area. The quality and speed of replication thus can be greatly improved. The effects of mold and viscosity of UV curable resin in the roller imprinting process have been investigated. The nanostructures can be successfully fabricated on the PC film with appropriate inner gas pressure in the gasbag and external pressure applied on the shaft. The antireflection and the hydrophobic effect of the fabricated PC film have been measured. The reflection has been dropped from 14.77% in the bare PC film to 2% in the PC film with AAO nanostructures. The contact angle has increase from 77.5° in the bare PC film to 124.1° in the PC film with AAO nanostructures. The results prove that an effective replication facility and process has been developed for fast and effective replication of nanostructures.
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40

Muscolino, G., und Alessandro Palmeri. „An earthquake response spectrum method for linear light secondary substructures“. 2007. http://hdl.handle.net/10454/611.

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Yes
Earthquake response spectrum is the most popular tool in the seismic analysis and design of structures. In the case of combined primary-secondary (P-S) systems, the response of the supporting P substructure is generally evaluated without considering the S substructure, which in turn is only required to bear displacements and/or forces imposed by the P substructure (¿cascade¿ approach). In doing so, however, dynamic interaction between the P and S components is neglected, and the seismic-induced response of the S substructure may be heavily underestimated or overestimated. In this paper, a novel CQC (Complete Quadratic Combination) rule is proposed for the seismic response of linear light S substructures attached to linear P substructures. The proposed technique overcomes the drawbacks of the cascade approach by including the effects of dynamic interaction and different damping in the substructures directly in the cross-correlation coefficients. The computational effort is reduced by using the eigenproperties of the decoupled substructures and only one earthquake response spectrum for a reference value of the damping ratio.
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