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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Análise da produção de banana orgânica no município de Itapajé - Ceará,Brasil / Analysis of the production of organic banana município of Itapajé - Ceará,Brazil

Andrade, José Alessandro Campos de January 2005 (has links)
Andrade, José Alessandro Campos de. Análise da produção de banana orgânica no município de Itapajé - Ceará,Brasil. 2005. 107 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Pró-Reitoria de Pesquisa e Pós-Graduação, Programa Regional de Pós-Graduação em Desenvolvimento e Meio Ambiente-PRODEMA, Fortaleza-CE, 2005. / Submitted by guaracy araujo (guaraa3355@gmail.com) on 2016-04-27T18:53:49Z No. of bitstreams: 1 2005_dis_jacandrade.pdf: 2039676 bytes, checksum: bc654bf01785878529d9d394c87871fa (MD5) / Approved for entry into archive by guaracy araujo (guaraa3355@gmail.com) on 2016-04-27T19:02:58Z (GMT) No. of bitstreams: 1 2005_dis_jacandrade.pdf: 2039676 bytes, checksum: bc654bf01785878529d9d394c87871fa (MD5) / Made available in DSpace on 2016-04-27T19:02:58Z (GMT). No. of bitstreams: 1 2005_dis_jacandrade.pdf: 2039676 bytes, checksum: bc654bf01785878529d9d394c87871fa (MD5) Previous issue date: 2005 / The present research has as main objective to describe the process of organic bananicultura practiced in Itapajé - Ceará, analyzing the aspects social, environmental and economical of this culture’s production. Furthermore, the objective specific are: to analyze organic banana's production after the creation of the Associação dos Fruticultores do Município de Itapajé – AFMI, to make the analyses technique, social and environmental and under the optical of organic banana's consumer's acceptance produced in Itapajé, to analyze the economical viability of the activity for the associated producers AFMI, to discuss some aspects related to the advantages and disadvantages of the production and the organic banana’s market. The study area is located in Itapajé, one of the largest producing of banana of the State of Ceará in Brazil. Itapajé is a city characterized by an intense modification in the physical space in mountainous areas. Primary and secondary datas were used to understand banana's organic production. The present study is classified as analytical-descriptive. Also, an analysis of the economical viability is elaborated for the Association's producers. The analysis of the data was studied through the descriptive statistics instruments and used tables, pictures and illustrations. The organic agriculture in Itapajé is an innovative experience. There are 16 sixteen organic banana´s producers that are linked to AFMI. These producers are developing that activity with many problems, for intance, low infrastructure and precariousness of the roads that harm the production’s drainage. In conclusion, some factors are decisive for the low productivity: the cultural treatments, no irrigation, incipient nutrients’replacement, irregular relief, a stony soil and an old plant banana. It was registered the organic manuring (composting of organic matter). Also, it was registered that the organic banana's producers are concerned with the environmental, they preserve the local biodiversity and they preserve an area of, at least, 20% of forest, the call legal reservation, in organic banana's properties. Finally, this activity of organic banana's production in Itapajé is profitable economically. / A presente pesquisa tem como objetivo principal descrever o processo de bananicultura orgânica praticada em Itapajé - Ceará, analisando os aspectos sociais, ambientais e econômicos dos produtores desta cultura. Além disso, são objetivos específicos: analisar a produção de banana orgânica com o advento da criação da Associação dos Fruticultores do Município de Itapajé – AFMI, efetuar as análises técnica, social e ambiental e sob a óptica de aceitação do consumidor de banana orgânica produzida em Itapajé, analisar a viabilidade econômica da atividade para os produtores associados à AFMI e discutir alguns aspectos relacionados às vantagens e desvantagens da produção e mercado da banana orgânica. A área de estudo está localizada em Itapajé, um dos maiores produtores de banana do Estado do Ceará, caracterizado por uma intensa modificação no espaço físico em áreas serranas. Fez-se uso de dados tanto primários quanto secundários. O presente estudo classifica-se como sendo de caráter analítico-descritivo. Efetua-se também uma análise da viabilidade econômica para os produtores ligados à referida Associação. A análise dos dados levantados foi efetuada utilizando-se tabelas, quadros e figuras, por meio dos instrumentos da estatística descritiva. A agricultura orgânica nesse Município é uma experiência inovadora, em que 16 produtores de banana orgânica, ligados à AFMI, vêm desenvolvendo esta atividade em meio a muitos problemas, tais como os de baixa infra-estrutura, principalmente, no que diz respeito à precariedade das estradas, que prejudicam o escoamento da produção. Concluiu-se que alguns fatores são determinantes para a baixa produtividade dos bananeirais, podendo-se citar os tratos culturais deficitários, a ausência de irrigação, a incipiente reposição de nutrientes, a alta declividade do relevo, solos pedregosos, além do fato do bananeiral já ser velho. Registrou-se que a adubação orgânica (compostagem) é utilizada nas propriedades e que os bananicultores demonstraram ter uma profunda preocupação com a questão ambiental, buscando a preservação da biodiversidade local, mantendo em suas propriedades uma área de, pelo menos, 20% de mata, ou seja, a chamada reserva legal. Por fim, quanto à viabilidade, concluiu-se que a atividade da produção de banana orgânica em Itapajé é rentável economicamente.
62

GeraÃÃo de Malhas por Refinamento Adptativo Usando GPU / Generation of mesh by adaptive refinement using GPU

Ricardo Lenz Cesar 24 April 2009 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O alto desempenho da GPU e o crescente uso dos seus mecanismos de programaÃÃo tÃm estimulado diversas aplicaÃÃes grÃficas de realidade virtual a explorar melhor o potencial desse dispositivo para alcanÃar nÃveis mais altos de realismo. Trabalhos tÃm surgido com um enfoque no refinamento da silhueta de malhas geomÃtricas, buscando expressar melhor a superfÃcie dos objetos tridimensionais sendo representados. O tipo de refinamento aplicado pode ser, por exemplo, uma suavizaÃÃo da malha bruta de um avatar, por meio da interpolaÃÃo de uma superfÃcie curva sobre suas faces. A ideia bÃsica à fazer uma discretizaÃÃo adaptativa da malha do objeto e entÃo gerar uma nova silhueta usando essa discretizaÃÃo. MÃtodos anteriores sÃo analisados e sÃo apresentadas melhorias que juntas formarÃo o mÃtodo proposto. O desempenho obtido à superior devido a uma exploraÃÃo melhor do paralelismo da GPU, e a tÃcnica proposta funciona suficientemente bem com malhas existentes sem necessidade de se projetar novos modelos para isso. / The high performance of the GPU and the increasing use of its programming mechanisms have stimulated several graphic applications of virtual reality to explore the potential of this device to achieve higher levels of realism. Studies have emerged with a focus on refining the silhouette of geometric meshes, seeking to express better the surface of three-dimensional objects being represented. The type of refining can be applied, for example, a fabric softening raw an avatar by means of an interpolation curve on their surface faces. Basic idea is to make an adaptive mesh discretization of the object and then generate a new silhouette using this discretization. Previous methods are analyzed and improvements are presented which together form the proposed method. The performance obtained is superior due to a better exploitation of parallelism of the GPU, and the proposed technique works well enough with existing mesh without the need to design new models for this.
63

Conception et vérification formelles des interfaces homme-machine multimodales : applications à la multimodalité en sortie / Formal modelling and verification of multimodal human computer interfaces : output multimodality

Mohand Oussaïd, Linda 16 December 2014 (has links)
Les interfaces homme-machine (IHM) multimodales offrent à l’utilisateur la possibilité de combiner les modalités d’interaction afin d’augmenter la robustesse et l’utilisabilité de l’interface utilisateur d’un système. Plus particulièrement, en sortie, les IHM multimodales permettent au système de restituer à l’utilisateur, l’information produite par le noyau fonctionnel en combinant sémantiquement plusieurs modalités. Dans l’optique de concevoir de telles interfaces pour des systèmes critiques, nous avons proposé un modèle formel de conception des interfaces multimodales en sortie. Le modèle proposé se décompose en deux modèles : le modèle de fission sémantique qui décrit la décomposition de l’information à restituer en informations élémentaires, et le modèle d’allocation qui spécifie l’allocation des modalités et médias aux informations élémentaires. Nous avons également développé une formalisation B Événementiel détaillée des deux modèles : fission sémantique et allocation. Cette formalisation a été instanciée sur des études de cas puis généralisée dans un processus de développement B Événementiel cadre dans lequel s’inscrivent les modèles de fission sémantique et d’allocation. Cette formalisation a permis de procéder à la vérification de propriétés de sûreté, de vivacité et d’utilisabilité. / Multimodal Human-Computer Interfaces (HCI) offer to users the possibility to combine interaction modalities in order to increase user interface robustness and usability. Specifically, output multimodal HCI allow system to return to the user, the information generated by the functional core by combining semantically different modalities. In order to design such interfaces for critical systems, we proposed a formal model for the design of output multimodal interfaces. The proposed model consists of two models: the semantic fission model describes the decomposition of the information to return into elementary information and the allocation model specifies the allocation of the elementary information with modalities and media. We have also developed a detailed Event B formalization for the two models: semantic fission and allocation. This formalization has been instantiated on case studies and generalized in an Event B development process framework including semantic fission and allocation models. This formalization allows to carry out safety, liveness and usability properties verification.
64

Failure Analysis of High Nickel Alloy Steel Seal Ring Used in Turbomachinery

Wang, Wenbo 23 March 2017 (has links)
The system of upper high nickel alloying steel seal ring and lower high nickel alloying steel seal ring, installed in the grooves of turbine, can extend out and fit with the wall of valve cage, resulting in forming a good seal under the pressure. In the project, the failure steel seal ring is considered. This situation had threatened the safety of the whole steam turbine system. The purpose of this study is to identify the failure cause of the steel seal ring used in nuclear steam turbines. New high nickel steel alloy seal ring was compared with the failed seal ring. The dimensions of macroscopic ring with clearly plastic deformation were measured using calipers. Surface morphology of ring was observed by optical microscopy through metallographic analysis. There is a lot of precipitation in the grain boundaries of used seal ring, along with smaller grain size than the new seal ring. To explore the composition of precipitation, scanning electron microscopy (SEM) with energy-dispersive spectrometer (EDS) were used. The results indicated that the concentration of titanium (Ti) and molybdenum (Mo) was higher in the precipitation of used seal ring. At the same time, the hardness and elastic modulus of used seal ring were reduced, measured by nanoindentation test. In-situ SEM tensile testing were used to record and analyze the generation of crack source and crack development under applied load. The reasons of the seal ring failure can be answered because of these experimental results at both macroscopic and microscopic scales. The main reason of the seal ring failure is a combination of long-term stress and elevated temperature during turbine operation. Complex work environment caused recrystallization and recovery, resulting in grain refinement and secondary phase precipitation. Further embodiment, recrystallization and recovery caused the elastic modulus and hardness of used seal ring decrease. Moreover, a lot of secondary phase precipitates appeared at grain boundaries during use. The appearance of secondary phase precipitates become the weakest part of used seal ring. The applied load lead to seal ring failure from the formation of microvoids to microvoids aggregated becoming microcracks until to the appearance of cracks at macroscopic scale. These changes of microscopic structure ultimately reflected in critical plastic deformation of used seal ring.
65

Multiresolution analysis for adaptive refinement of multiphase flow computations

Grieb, Neal Phillip 01 July 2010 (has links)
Flows around immersed boundaries exhibit many complex, well defined and active dynamical structures. In fact, features such as shock waves, strong vorticity concentrations in shear layers, wakes, or boundary layer regions are critical elements in representing the dynamics of a flow field. In order to capture the correct kinematic and dynamic quantities associated with the fluid flows, one must be able to efficiently refine the computational mesh around areas containing high gradients of pressure, density, velocity, or other suitable flowfield variables that characterize distinct structures. Although there are techniques which utilize simple gradient-based Local Mesh Refinement (LMR) to adapt resolution selectively to capture structures in the flow, such methods lack the ability to refine structures based on the relative strengths and scales of structures that are presented in the flow. The inability to adequately define the strength and scale of structures typically results in the mesh being over-refined in regions of little consequence to the physical definition of the problem, under-refined in certain regions resulting in the loss of important features, or even the emergence of false features due to perturbations in the flowfield caused by unnecessary mesh refinement. On the other hand, significant user judgment is required to develop a "good enough" mesh for a given flow problem, so that important structures in the flowfield can be resolved. In order to overcome this problem, multiresolution techniques based on the wavelet transform are explored for feature identification and refinement. Properties and current uses of these functional transforms in fluid flow computations will be briefly discussed. A Multiresolution Transform (MRT) scheme is chosen for identifying coherent structures because of its ability to capture the scale and relative intensity of a structure, and its easy application on non-uniform meshes. The procedure used for implementation of the MRT on an octree/quadtree LMR mesh is discussed in detail, and techniques used for the identification and capture of jump discontinuities and scale information are also presented. High speed compressible flow simulations are presented for a number of cases using the described MRT LMR scheme. MRT based mesh refinement performance is analyzed and further suggestions are made for refinement parameters based on resulting refinement. The key contribution of this thesis is the identification of methods that lead to a robust, general (i.e. not requiring user-defined parameters) methodology to identify structures in compressible flows (shocks, slip lines, vertical patterns) and to direct refinement to adequately refine these structures. The ENO-MRT LMR scheme is shown to be a robust, automatic, and relatively inexpensive way of gaining accurate refinement of the major features contained in the flowfield.
66

Computationally Assisted NMR Crystallography: A Path to Unusually High-Resolution Crystal Structures

Wang, Luther 11 April 2022 (has links)
Crystallography has traditionally been studied by diffraction methods involving X ray or neutron radiation. These methods have some limitations, from requiring the substance under study to form single crystals to the limited ability of X rays to locate hydrogen atoms. While neutron radiation can characterize hydrogens, it is expensive, not readily available and has its own particular limits on resolution. It this dissertation, it is demonstrated that NMR is extraordinarily sensitive to atomic positions, with variations of mere tens of femtometers creating statistically distinguishable chemical shift changes. To date, no other means of measurement can detect structural changes at this scale. This thesis presents a NMR based refinement technique that refines existing X ray structures to an unprecedented resolution. The refinement uses computational methods to make theoretical models then fits these models to the experimental data. This refinement process can also be modified to generate positional uncertainties known as the anisotropic displacement parameters, or ADPs, to accompany the refined structure. This creation of ADPs fulfills requirements set by the international union of crystallography that all deposited crystal structures contain ADPs.
67

An Integrated Theory of Type-Based Static and Dynamic Verification / 型に基づく静的・動的検証の統合理論

Sekiyama, Taro 23 March 2016 (has links)
© 2015 Springer. http://dx.doi.org/10.1007/978-3-319-26529-2_11© 2015 ACM, Inc. http://doi.acm.org/10.1145/2676726.2676996 / 京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第19863号 / 情博第614号 / 新制||情||107(附属図書館) / 32899 / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 五十嵐 淳, 教授 山本 章博, 教授 岡部 寿男 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
68

Facial Expressions and Behaviours Associated with Pain in Japanese Macaques / ニホンザルにおける痛みに関連した表情および行動に関する研究

Gris, Vanessa Nadine 23 May 2023 (has links)
付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 新制・課程博士 / 博士(理学) / 甲第24780号 / 理博第4974号 / 新制||理||1710(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 明里 宏文, 准教授 足立 幾磨, 教授 平田 聡 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
69

A Selective Approach to Hexahedral Refinement of Unstructured Conformal Meshes

Parrish, Michael Hubbard 13 July 2007 (has links) (PDF)
Hexahedral refinement increases the density of an all-hexahedral mesh in a specified region, improving numerical accuracy. Previous research using solely sheet refinement theory made the implementation computationally expensive and unable to effectively handle multiply-connected transition elements and self-intersecting hexahedral sheets. The Selective Approach method is a new procedure that combines two diverse methodologies to create an efficient and robust algorithm able to handle the above stated problems. These two refinement methods are: 1) element by element refinement and 2) directional refinement. In element by element refinement, the three inherent directions of a hexahedron are refined in one step using one of seven templates. Because of its computational superiority over directional refinement, but its inability to handle multiply-connected transition elements, element by element refinement is used in all areas of the specified region except regions local to multiply-connected transition elements. The directional refinement scheme refines the three inherent directions of a hexahedron separately on a hexahedron by hexahedron basis. This differs from sheet refinement which refines hexahedra using hexahedral sheets. Directional refinement is able to correctly handle multiply-connected transition elements. A ranking system and propagation scheme allow directional refinement to work within the confines of the Selective Approach Algorithm.
70

Localized Coarsening of Conforming All-Hexahedral Meshes

Woodbury, Adam C. 28 July 2008 (has links) (PDF)
Finite element mesh adaptation methods can be used to improve the efficiency and accuracy of solutions to computational modeling problems. For many finite element modeling applications, a conforming all-hexahedral mesh is preferred. When adapting a hexahedral mesh, localized modifications that preserve topologic conformity are often desired. Effective hexahedral refinement methods that satisfy these criteria have recently become available. However, due to hexahedral mesh topology constraints, little progress has been made in the area of hexahedral coarsening. This thesis presents a new method to locally coarsen conforming all-hexahedral meshes. The method works on both structured and unstructured meshes and is not based on undoing previous refinement. Building upon recent developments in quadrilateral coarsening, the method utilizes hexahedral sheet and column operations, including pillowing, column collapsing, and sheet extraction. A general algorithm for automated coarsening is presented and examples of models that have been coarsened are shown. While results are promising, further work is needed to improve the automated process.

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