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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.
121

Development Of A 3-camera Vision System And The Saddle Motion Analysis Of Horses Via This System

Dogan, Gozde 01 September 2009 (has links) (PDF)
One of the purposes of this study is to develop a vision system consisting of 3 inexpensive, commercial cameras. The system is intended to be used for tracking the motion of objects in a large calibration volume, typically 6.5 m. wide and 0.7 m. high. Hence, a mechanism is designed and constructed for the calibration of the cameras. The second purpose of the study is to develop an algorithm, which can be used to obtain the kinematic data associated with a rigid body, using a vision system. Special filters are implemented in the algorithm to identify the 3 markers attached on the body. Optimal curves are fitted to the position data of the markers after smoothing the data appropriately. The outputs of the algorithm are the position, velocity and acceleration of any point (visible or invisible) on the body and the angular velocity and acceleration of the body. The singularities associated with the algorithm are also determined. Using the vision setup and the developed algorithm for tracking the kinematics of a rigid body, the motions of the saddles of different horses are investigated for different gaits. Similarities and differences between horses and/or gaits are analyzed to lead to quantitative results. Using the limits induced by the whole body vibration of humans, for the first time in the world, daily, allowable riding time and riding distances are determined for different horses and gaits. Furthermore, novel, quantitative horse comfort indicators are proposed. Via the experiments performed, these indicators are shown to be consistent with the comfort assessment of experienced riders. Finally, in order to implement the algorithms proposed in this study, a computer code is developed using MATLAB&reg / .
122

Robust Preconditioners Based on the Finite Element Framework

Bängtsson, Erik January 2007 (has links)
Robust preconditioners on block-triangular and block-factorized form for three types of linear systems of two-by-two block form are studied in this thesis. The first type of linear systems, which are dense, arise from a boundary element type of discretization of crack propagation problems. Numerical experiment show that simple algebraic preconditioning strategies results in iterative schemes that are highly competitive with a direct solution method. The second type of algebraic systems, which are sparse, indefinite and nonsymmetric, arise from a finite element (FE) discretization of the partial differential equations (PDE) that describe (visco)elastic glacial isostatic adjustment (GIA). The Schur complement approximation in the block preconditioners is constructed by assembly of local, exactly computed Schur matrices. The quality of the approximation is verified in numerical experiments. When the block preconditioners for the indefinite problem are combined with an inner iterative scheme preconditioned by a (nearly) optimal multilevel preconditioner, the resulting preconditioner is (nearly) optimal and robust with respect to problem size, material parameters, number of space dimensions, and coefficient jumps. Two approaches to mathematically formulate the PDEs for GIA are compared. In the first approach the equations are formulated in their full complexity, whereas in the second their formulation is confined to the features and restrictions of the employed FE package. Different solution methods for the algebraic problem are used in the two approaches. Analysis and numerical experiments reveal that the first strategy is more accurate and efficient than the latter. The block structure in the third type of algebraic systems is due to a fine-coarse splitting of the unknowns. The inverse of the pivot block is approximated by a sparse matrix which is assembled from local, exactly inverted matrices. Numerical experiments and analysis of the approximation show that it is robust with respect to problem size and coefficient jumps.
123

A game theoretic analysis of adaptive radar jamming

Bachmann, Darren John Unknown Date (has links) (PDF)
Advances in digital signal processing (DSP) and computing technology have resulted in the emergence of increasingly adaptive radar systems. It is clear that the Electronic Attack (EA), or jamming, of such radar systems is expected to become a more difficult task. The reason for this research was to address the issue of jamming adaptive radar systems. This required consideration of adaptive jamming systems and the development of a methodology for outlining the features of such a system is proposed as the key contribution of this thesis. For the first time, game-based optimization methods have been applied to a maritime counter-surveillance/counter-targeting scenario involving conventional, as well as so-called ‘smart’ noise jamming.Conventional noise jamming methods feature prominently in the origins of radar electronic warfare, and are still widely implemented. They have been well studied, and are important for comparisons with coherent jamming techniques.Moreover, noise jamming is more readily applied with limited information support and is therefore germane to the problem of jamming adaptive radars; during theearly stages when the jammer tries to learn about the radar’s parameters and its own optimal actions.A radar and a jammer were considered as informed opponents ‘playing’ in a non-cooperative two-player, zero-sum game. The effects of jamming on the target detection performance of a radar using Constant False Alarm Rate (CFAR)processing were analyzed using a game theoretic approach for three cases: (1) Ungated Range Noise (URN), (2) Range-Gated Noise (RGN) and (3) False-Target (FT) jamming.Assuming a Swerling type II target in the presence of Rayleigh-distributed clutter, utility functions were described for Cell-Averaging (CA) and Order Statistic (OS) CFAR processors and the three cases of jamming. The analyses included optimizations of these utility functions, subject to certain constraints, with respectto control variables (strategies) in the jammer, such as jammer power and spatial extent of jamming, and control variables in the radar, such as threshold parameter and reference window size. The utility functions were evaluated over the players’ strategy sets and the resulting matrix-form games were solved for the optimal or ‘best response’ strategies of both the jammer and the radar.
124

Estudo de expansões assintóticas, avaliação numérica de momentos das distribuições beta generalizadas, aplicações em modelos de regressão e análise discriminante

BRITO, Rejane dos Santos 20 March 2009 (has links)
Submitted by (ana.araujo@ufrpe.br) on 2016-08-10T13:00:13Z No. of bitstreams: 1 Rejane dos Santos Brito.pdf: 1642561 bytes, checksum: 084711a62c79f703133a032643c8d19f (MD5) / Made available in DSpace on 2016-08-10T13:00:13Z (GMT). No. of bitstreams: 1 Rejane dos Santos Brito.pdf: 1642561 bytes, checksum: 084711a62c79f703133a032643c8d19f (MD5) Previous issue date: 2009-03-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / We make a review about Edgeworth, Lugannani-Rice, Daniels and Cordeiro-Ferrari asymptotic approximations. We use the Cordeiro-Ferrari asymptotic approximation to approximate the gamma distribution G(m;f ) by the exponential distribution with mean a. In a further application, based on the statistical proposed by them, we approximate the t-Student distribution with n degrees of freedom using the normal standard distribution. Moreover, we realize a study about the functionalities of the beta generalized distributions. We obtain moments of the generalized beta distributions using the Lauricella and Kampé de Fériet generalized functions. Beyond this, we propose a new generalized beta distribution called beta power. Finally, we realize some applications in regression models by logistic regression and further more using discriminant analysis. / Inicialmente, realiza-se uma revisão literária sobre as expansões assintóticas de Daniels, Edgeworth, Lugannani-Rice e Cordeiro-Ferrari. Mediante uso da expansão de Cordeiro- Ferrari, torna-se possível realizar um estudo correspondente a aproximação da distribuição gama G(m;f ) em função da distribuição exponencial com média a. E, ainda, numa outra aplicação, faz-se a aproximação da distribuição t-Student com n graus de liberdade em função da distribuição normal padrão. Além disso, apresenta-se um estudo correspondente às funcionalidades das distribuições beta generalizadas e, ainda, a obtenção dos momentos das distribuições beta generalizadas mediante as funções de Lauricella e generalizada de Kampé de Fériet. Propõe-se, ainda, a generalização da distribuição power como sendo uma nova distribuição beta generalizada. Por fim, realizam-se algumas aplicações em modelos de regressão, mediante regressão logística, bem como em modelos de análise discriminante.
125

La cécidomyie orange du blé, Sitodiplosis mosellana (Géhin): appréhension des risques et gestion intégrée / Orange wheat blossom midge, Sitodiplosis mosellana (Géhin): risk evaluation and pest management

Jacquemin, Guillaume 03 April 2014 (has links)
La cécidomyie orange du blé, Sitodiplosis mosellana (Géhin), est un ravageur commun du froment. Présente sur les trois continents de l’hémisphère Nord, cette espèce est connue depuis deux siècles mais son contrôle reste difficile tant par sa présence discrète que par ses effectifs hautement variables. En Wallonie, les niveaux d’infestations sont globalement faibles mais atteignent localement des seuils inquiétants.<p>Au début des années 2000, la phéromone sexuelle de S. mosellana a été identifiée au Canada. Cette découverte a permis la fabrication de pièges qui ont considérablement amélioré la détection et la mesure des vols de cet insecte minuscule. De 2007 à 2010, les captures de S. mosellana ont été mesurées quotidiennement dans plusieurs dizaines de champs de Wallonie, aux historiques et aux couverts variés.<p>Les volumes de captures au piège à phéromone sexuelle ont été très importants. Il a fallu en étudier la signification, notamment en termes de mesure du risque. En effet, si les mâles sont efficacement capturés, seules les femelles constituent un risque de dégâts. L’interprétation correcte des captures à l’aide de ce type de piège, a été rendue possible par l’observation de différences fondamentales concernant la mobilité et la distribution spatiale des mâles et des femelles de S. mosellana. Même s’ils ne mesurent pas directement l’émergence proprement dite, les pièges à phéromone ont permis, grâce à leur très grande sensibilité, de préciser les connaissances sur l’émergence des adultes et de révéler que plusieurs vagues d’émergence pouvaient se succéder au cours d’une même année.<p>La prévision des émergences de la cécidomyie orange du blé, constitue la clé de voûte de la lutte contre ce ravageur dont un contrôle efficace par des insecticides ne se justifie éventuellement que lorsque la courte saison des pontes coïncide avec l’épiaison des froments. Les patrons d’émergence obtenus par les pièges ont été confrontés aux prévisions de différents modèles conçus en Europe ou en Amérique du Nord, et appliqués aux conditions météorologiques observées de 2007 à 2010. Aucun de ces modèles n’a prévu correctement les émergences sur l’ensemble des quatre années.<p>Les données d’émergence obtenues à l’aide des pièges à phéromone (effectifs élevés et relevés quotidiens) ont fait apparaître une relation de cause à effet entre, d’une part les vagues d’émergences et, d’autre part les épisodes pluvieux observés trois à six semaines plus tôt. L’écart entre une &61618;pluie inductrice&61618; et la vague d’émergence induite correspondante s’est avéré constant en termes d’accumulation de température :il équivaut à 160 degrés-jours en base 7°C. Partant de ce constat et des acquis des modèles antérieurs, un modèle prévisionnel original des émergences a été développé et validé sur le terrain. Allié à une meilleure connaissance de la biologie du ravageur, il constitue un outil majeur de la lutte intégrée.<p>Par ailleurs, les travaux menés ont également révélé l’existence d’un biais fréquent dans les essais d’évaluation des variétés, entraîné par la concentration des pontes de cécidomyie orange sur les premières parcelles atteignant le stade épiaison. Dans le système d’évaluation en vigueur, notamment pour l’inscription dans les catalogues nationaux, ce biais conduit à une sous-estimation du potentiel de rendement des variétés de blé les plus précoces.<p>Enfin, la découverte du rôle inducteur des pluies sur l’émergence des adultes a été exploitée en conditions contrôlées pour planifier des émergences échelonnées, et pour disposer, pendant une longue période, de jeunes adultes prêts à pondre. Cette application permet dès à présent de mesurer en serre le niveau de résistance des variétés exposées de façon homogène à l’insecte, quel que soit leur degré de précocité.<p>De diverses façons, cette étude contribue à une meilleure connaissance de la cécidomyie orange du blé et offre de nouveaux outils pour la lutte intégrée contre ce ravageur.<p><p>--------------------------------------------------<p><p>The orange wheat blossom midge, Sitodiplosis mosellana (Géhin), a common pest of wheat throughout the northern hemisphere, is known for two centuries but remains difficult to control due to its discrete behavior and its highly variable population level.<p>In general, the infestation levels in Wallonia (Belgium) are low, although levels could locally exceed worrying thresholds. <p>In the early 2000s, the sexual pheromone of S. mosellana has been identified in Canada. This discovery has led to the manufacturing of traps which have greatly improved the detection of this tiny insect. From 2007 to 2010 in Wallonia, S. mosellana captures have been daily registered in about 20 fields with different cropping histories and grown with different crops.<p>Insect captures by pheromone traps were numerous. Relation between amount of captures and risk measurement has been studied. As expected, only the males are attracted by the pheromone and the risk of ears infestation is mainly related to the presence of females. The correct interpretation of captures in pheromone traps has been established by the observation of fundamental differences between males and females concerning their mobility and their spatial distribution. <p>Despite the fact that pheromone traps are not real emergence traps, they have led to new information on adult emergence indicating that several emergence waves can be consecutive during the same year. <p>Forecasting the emergence of the adult orange wheat blossom midge is a key element on pest management. Insecticides treatments are sometimes justified when the egg laying period of the insect coincides with ear emergence of wheat. Emergence patterns established from captures of pheromone traps have been compared with the forecast of several models built in Europe or North America. These forecasting models were used with the meteorological data observed from 2007 until 2010. None of the six tested models provided a reliable forecast across the four years of our study. <p>Emergence data from catches in pheromone traps were very accurate because the number of catches were high and were taken each day. This emergence data showed a relation between emergence waves and rainfalls occurring during the preceding 3 to 6 weeks. The lag between inductive rain and emergence wave is constant in terms of temperature accumulation: it is equivalent to 160 degree–days above 7°C. This discovery, combined with experience from previous models, was incorporated into a new forecasting model.<p>In addition, the present work has also revealed the existence of a common bias in variety evaluation trials leading sometime to the concentration of the eggs in the earliest earing variety. In the current evaluation system, this bias leads to a sub-evaluation of the yield for the most precocious varieties. <p>Finally, the discovery of the inductive rain for adult emergence has been used in the screening for resistant varieties to S. mosellana by providing adults during the complete duration of the test. This application of the model allows to measure, under controlled conditions, the level of resistance of all varieties (early and late heading varieties) which are exposed homogeneously to the insect.<p>In total, this study has contributed to a better understanding of the orange wheat blossom midge and provides some new tools in the management of this pest.<p> / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
126

Etude du comportement d'un implant BCP pour la réparation du septum nasal

Le Taillandier de Gabory, Ludovic 04 May 2010 (has links)
Le septum nasal joue un rôle prépondérant dans la croissance de l’étage moyen de la face et la physiologie ventilatoire. Sa solidité, sa rectitude et sa position sagittale sont déterminantes pour percevoir un confort respiratoire diurne et nocturne. Vulnérable aux traumatismes de part sa projection antérieure, la destruction ou l’inefficience de son squelette entraîne une demande de réparation fonctionnelle et esthétique. Dans les cas les plus sévères, le remplacement tissulaire fait appel à des volumineux greffons autologues pour lesquels la morbidité du site donneur et leurs imperfections propres restent un écueil. Pour les remplacer, certains biomatériaux ont été essayés de manière empirique sans donner de résultats fiables. Le premier objectif de notre travail été d’évaluer le comportement d’un implant phosphocalcique biphasique pour la reconstruction du septum nasal afin d’éviter ces greffons tout en répondant aux objectifs biofonctionnels locaux, au contact d’un milieu septique et susceptible d’être exposé aux particules aéroportées de l’environnement. Le deuxième objectif était d’évaluer la cytotoxicité des nanotubes de carbone à double paroi sur des cellules de l’arbre respiratoire, premier organe concerné par une exposition potentielle lors de leur fabrication. Par la suite, les résultats de ces deux sujets différents ont été utilisés de manière synergique pour répondre au troisième objectif qui était, d’évaluer l’influence des nanotubes de carbone sur la cicatrisation du septum nasal en présence ou non de l’implant phosphocalcique. / The nasal septum plays a paramount role in the growth of the face and respiratory physiology. Its solidity, its straightness and its sagittal position are determining to perceive a diurnal and night respiratory comfort. Vulnerable to the traumas, the destruction or the inefficiency of its skeleton involves request for a functional and aesthetic repair. In severe cases, the tissue replacement requires large autologous grafts for which the morbidity of the donor site and their own imperfections remain a problem. To replace them, certain biomaterials were tested in an empirical way without giving reliable results. The primary goal of our work was to evaluate the behaviour of a biphasic phosphocalcic implant to repair nasal septum in order to avoid these grafts with an adapted biofunctional implant, exposed to the septic nasal content and the airborne particles of the environment. The second objective was to evaluate the cytotoxicity of the double wall carbon nanotubes on epithelial respiratory cells, first organ concerned by a potential exposure during their manufacture. Thereafter, the results of these two different subjects were used in a synergistic way to answer the third objective which was, to evaluate the influence of the carbon nanotubes on the cicatrization of the nasal septum in presence or not of the phosphocalcic implant.
127

Územní studie rozvojového území města Velké Meziříčí / Urban study of development area city - Velké Meziříčí

Klímová, Radka January 2017 (has links)
The project deals with the use of the site near the historical center of Velké Meziříčí. Originally there were production facilities that were already demolished. At present, this space is in no way used. This territorial study attempts to overcome the possibility of using the site for the emergence of a new urban structure that fulfills the function of housing, civic amenities and also the transport function.
128

Centrum odpočinku v Lavičkách / Center of Rest in Lavičky

Pospíšilová, Iveta January 2018 (has links)
The topic of this master´s thesis is a new building design of recreation centre in Lavičky and processing of project documentation for this building realization. This thesis is furthermore completed with two specializations. It deals specifically with a specialisation in the field of technical facilities of buildings – heating and air conditioning. The recreation centre is a complex of two units that will provide restaurant and accommodation services with leisure activities facilities. In one of the units there is designed an accommodation facility with smaller wellness area, in the other unit there is designed a restaurant. The estate where the units are located occurs in the north part of the village Lavičky. This locality is built up by family houses and apartment blocks. The architectural solution of the designed units follows on from the concept of simple country object where the object has the shape of rectangle ground plan and is roofed by typical saddle roof. The building of the restaurant and also the guest house is in the shape of rectangle and is roofed by double sheathed saddle roof with metal folded roofing in dark grey colour. As well it utilises modern elements of architecture as big window openings or dormers. The filling of the openings will be accomplished by wooden windows in natural shade. The façade of the units is designed in that way to match both unis together. It is solved by white façade paint in combination with cement splinter panels imitating wood or cement splinter panels in grey colour and is completed by outdoor wooden pergola or wooden storm porch. The wall base part is formed by mosaic façade in grey colour. The layout solution of the units follows on from operation requirements of the particular services and they are separated in space for customers and for operation space. In the unit of the guest house there are designed 9 suites with 22 beds. In the ground floor there is designed one suite for persons with reduced mobility and o
129

Mateřská školka / Kidsgarden

Kuttelwascherová, Kristína January 2018 (has links)
This diploma thesis is a project of a two-storey building of a Kindergarten. The building will be used for educating preschool children. On the ground floor, there are two base classrooms, one in each wing of the building. Each classroom has several zones (relaxing, playing, creating). Each classroom also has its own dressing room, washroom + toilets. On the ground floor, we can also find facilities for teachers and the principal office. Since finished food will be delivered, the building only contains a food preparation facility + dry storage. The second floor is accessible either by stairs or by elevator. On the second floor, there is another base classroom with its own dressing room and a washroom with toilet. Food is transported from the first floor by elevator, which is not designed for transporting people. On the second floor, there is also the teacher´s base + large social hall for occasional events. The kindergarten building has an atypical layout. The building is partly roofed by a flat roof and partly by a gabled roof. The project was processed using the computer program AutoCAD. During processing, emphasis was placed on the correct layout, architectural design and safe use of the building.
130

Hotel v Krkonoších / Hotel in Giant

Polák, Tomáš January 2018 (has links)
This master´s thesis proposes a design for a new hotel in the Giant. This master´s thesis is elaborated in the form of project documentation for construction. The building is located in the village Spindleruv Mlyn in sloping terrain. The object is designed from a two-way wall system, the porotherm, and the ceilings are designed as stacked also from the porotherm system. The building is a rectangular ground plan with a saddle roof and a dormer. Roof cover is designed from Tondach-baked bags and design is made of wooden elements. The perimeter walls of the underground floor will be made of concrete blocks of BS Klatovy. The internal staircase will be reinforced concrete. The elevator shaft across all floors will be fitted with an evacuation lift. The building will be insulated with a certified ETICS thermal insulation system.

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