Šiame darbe nagrinėjamos bepiločio skraidančio sparno aerodinaminės charakteristikos. Pasirinktas sparno profilis EPPLER 328. Pirmiausia išanalizuojami skaitiniai aerodinaminių charakteristikų tyrimo metodai. Atlikus skaičiavimus pagal pasirinktus aspektus, naudojant programą XFLR5 gauti duomenys apibendrinami bei išanalizuojami. Ištirtos keliamosios jėgos koeficientų, pasipriešinimo jėgos koeficientų, aerodinaminės kokybės reikšmės esant atitinkamiems atakos kampams. Naudojantis tyrimo rezultatais padarytas bepilotis skraidančio sparno orlaivis ir atlikti skrydžiai. Visa informacija apibendrinama ir pateikiamos gautų rezultatų išvados. Darbo apimtis – 66 p. teksto be priedų, 39 paveikslai, 6 lentelės, 24 bibliografiniai šaltiniai. / The investigation analyzes unmanned flying wing aerodynamic characteristics. Choosen airfoil EPPLER 328. Firstly, analyzing theoretical calculation methods. All relative data compared and analyzed after calculation with program XFLR5. Analyzed lift force coefficient, drag force coefficient, aerodynamic coefficient under realative angles of attack. Unmanned flying wing was built using the results of compared and analyzed aerodynamic data and test flights were made. All information summarized and produced conclusion. Thesis consists of: 66 p. text without appendixes, 39 pictures, 6 tables, 24 bibliographical entries.

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This thesis describes the molecular characterisation of Broome virus (BroV), a new fusogenic orthoreovirus species that was isolated from a little red flying-fox (Pteropus scapulatus) in Broome, Western Australia in 2002. The BroV genome consists of ten segments of dsRNA, each containing a plus-strand with a 3’ terminal pentanucleotide sequence that is conserved amongst all viruses in the genus Orthoreovirus, family Reoviridae, and a 5’ terminal pentanucleotide sequence that is unique to BroV. With the exception of S4, all genome segments are predicted to encode a single translation product producing a total of seven structural and four nonstructural proteins. All BroV proteins were identified as homologues of known orthoreovirus proteins and shown to have similar secondary structure and possess key conserved amino acid sequence motifs and structural features implicated in biological function. Notably, no cell-attachment protein gene homologue was identified in the BroV genome suggesting the use of an alternate cell entry mechanism to that employed by most orthoreoviruses. The amino acid sequence identity between cognate BroV proteins and those of other orthoreoviruses ranges from 13-50%, which is too low for BroV to be considered a new isolate of any established orthoreovirus species group. Phylogenetic analyses based on both structural and nonstructural proteins provide additional evidence to support this claim. It is proposed that BroV is the prototype member of a new sixth species group Broome virus, in the genus Orthoreovirus. The complete genome characterisation of BroV provided an opportunity to produce recombinant proteins in Escherichia coli and to generate polyclonal antibodies in rabbits for use in research and surveillance. Such reagents proved valuable in the experimental identification of the fusion-associated small transmembrane (FAST) protein p13 that is responsible for the syncytia observed in BroV-infected cells. Despite the low amino acid sequence identity between the FAST proteins of different orthoreovirus species they possess conserved structural features that have been implicated in biological function. Of these conserved features, the BroV p13 protein is predicted to possess one transmembrane domain, a C-terminal polybasic region, a C-terminal hydrophobic patch and an N-terminal myristoylation consensus sequence. The unique repertoire and arrangement of sequence-predicted structural features identified in p13 indicate that it is a novel fifth member of the FAST protein family. The BroV-specific immunological reagents were also used to develop an enzyme-linked immunosorbent assay (ELISA) suitable for serological screening. A survey of flying-foxes from Papua New Guinea (PNG) revealed that BroV or BroV-like viruses are currently circulating in these animals. This demonstrates that BroV is not limited to the Australian continent.

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Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains x, 431 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 416-431).

Dans ce travail, nous avons premièrement développé et caractérisé des capteurs de flux optique robustes aux changements de conditions lumineuses inspirés par le système visuel de la mouche et mesurant la vitesse angulaire à l'aide de l'algorithme appelé "time of travel". En particulier, nous avons comparé les performances de capteurs mesurant visuellement la vitesse angulaire en intérieur et en extérieur. Les résultats de nos capteurs bio-inspirés ont aussi été comparés avec des capteurs de souris optique. Enfin, une nouvelle implémentation de l'algorithme "time of travel" a été proposée réduisant la charge de calcul de l'unité de traitement.Dans le cadre du projet européen CurvACE (Curved Artificial Compound Eye), nous avons aussi participé au développement du premier oeil composé courbé artificiel capable de mesurer le flux optique à haute vitesse sur une large gamme de lumière ambiante. En particulier, nous avons caractérisé ce capteur et montré sa capacité à mesurer le flux optique à l'aide de plusieurs algorithmes.Finalement, nous avons aussi développé un robot aérien miniature attaché appelé BeeRotor équipé de capteurs et de stratégies de vol imitant les insectes volants et se déplaçant de manière autonome dans un tunnel contrasté. Ce robot peut expliquer comment les abeilles contrôlent leur vitesse et leur position à l'aide du flux optique, tout en démontrant que des solutions alternatives existent aux systèmes couramment utilisés en robotique. Basé seulement sur des boucles de contrôle réagissant à l'environnement, cet hélicoptère a démontré sa capacité à voler de manière autonome dans un environnement complexe et mobile. / In this thesis, we first developed and characterized optic flow sensors robust to illuminance changes inspired by the visual system of the fly and computing the angular speed thanks to the "time of travel" scheme. In particular, we have compared the performances of sensors processing the visual angular speed based on a standard retina or an aVLSI retina composed of pixels automatically adapting to the background illuminance in indoor and outdoor environments. The results of such bio-inspired sensors have also been compared with optic mouse sensors which are used nowadays on Micro Aerial Vehicles to process the optic flow but only in outdoor environments. Finally, a new implementation of the "time of travel" scheme has been proposed reducing the computational load of the processing unit.In the framework of the European project CurvACE, we also participated to the design and development of the first curved artificial compound eye including fast motion detection in a very large range of illuminations. In particular, we characterized such sensor showing its ability to extract optic flow using different algorithms.Finally, we also developed a tethered miniature aerial robot equipped with sensors and control strategies mimicking flying insects navigating in a high-roof tunnel. This robot may explain how honeybees control their speed and position thanks to optic flow, while demonstrating alternative solution to classical robotic approach relying on ground-truth and metric sensors. Based only on visuomotor control loops reacting suitably to the environment, this rotorcraft has shown its ability to fly autonomously in complex and unstationary tunnels.

Immersed boundary methods are a class of techniques in computational fluid dynamics where the Navier-Stokes equations are simulated on a computational grid that does not conform to the interfaces in the domain of interest. This facilitates the simulation of flows with complex moving and deforming geometries without considerable effort wasted in generating the mesh. The first part of this dissertation is concerned with the aerodynamics of the cross-section of a species of flying snake, Chrysopelea paradisi (paradise tree snake). Past experiments have shown that the unique cross-section of this snake, which can be described as a lifting bluff body, produces an unusual lift curve--with a pronounced peak in lift coefficient at an angle of attack of 35 degrees for Reynolds numbers 9000 and beyond. We studied the aerodynamics of the cross-section using a 2-D immersed boundary method code. We were able to qualitatively reproduce the spike in the lift coefficient at the same angle of attack for flows beyond a Reynolds number of 2000. This phenomenon was associated with flow separation at the leading edge of the body that did not result in a stall. This produced a stronger vortex and an associated reduction in pressure on the dorsal surface of the snake cross-section, which resulted in higher lift. The second part of this work deals with the analysis of the direct forcing method, which is a popular immersed boundary method for flows with rigid boundaries. We begin with the fully discretized Navier-Stokes equations along with the appropriate boundary conditions applied at the solid boundary, and derive the fractional step method as an approximate block LU decomposition of this system. This results in an alternate formulation of the direct forcing method that takes into consideration mass conservation at the immersed boundaries and also handles the pressure boundary conditions more consistently. We demonstrate that this method is between first and second-order accurate in space when linear interpolation is used to enforce the boundary conditions on velocity. We then develop a theory for the order of accuracy of the direct forcing method with linear interpolation. For a simple 1-D case, we show that the method can converge at a range of rates for different locations of the solid body with respect to the mesh. But this effect averages out in higher dimensions and results in a scheme that has the same order of accuracy as the expected order of accuracy of the interpolation at the boundary. The discrete direct forcing method for the Navier-Stokes equations exhibits an order of accuracy between 1 and 2 because the velocities at the boundary are linearly interpolated, but the resulting boundary conditions on the pressure gradient turn out to be only first-order accurate. We recommend linearly interpolating the pressure gradient as well to make the method fully second-order accurate. We have also developed two open source codes in the course of these studies. The first, cuIBM, is a two-dimensional immersed boundary method code that runs on a single GPU. It can simulate incompressible flow around rigid bodies with prescribed motion. It is based on the general idea of a fractional step method as an approximate block LU decomposition, and can incorporate any type of immersed boundary method that can be made to fit within this framework. The second code, PetIBM, can simulate both two and three-dimensional incompressible flow and runs in parallel on multiple CPUs. Both codes have been validated using well-known test cases.