Suburbs in Melbourne present to us a unique context with which a new approach towards urban form can be devised using the existing conditions and opportunities found with infrastructural developments. This thesis contains the investigations on the various 'pathologies' of the urban fabric specifically on the potential use of 'Spaces Left-Over After Planning' as by-product to infrastructural development in relation to the reinvigoration of Melbourne suburbs under the influence of current and future metropolitan growth pressures. The contents of the research aims to demonstrate the potentials for urban diversification followed by densification using the already inherent characteristics of the selected suburbs (Oakleigh, Waverley and Broadmeadows) to facilitate the metropolitan expansion of Melbourne with the intention of encouraging ways in which suburban fabric can reach its maturity along with new infrastructural developments to foster community engagement.

This thesis makes a number of new contributions to control and sensing for unmanned vehicles. I begin by developing a non-linear simulation of a small unmanned helicopter and then proceed to develop new algorithms for control and sensing using the simulation. The work is field-tested in successful flight trials of biologically inspired vision and neural network control for an unstable rotorcraft. The techniques are more robust and more easily implemented on a small flying vehicle than previously attempted methods.¶ Experiments from biology suggest that the sensing of image motion or optic flow in insects provides a means of determining the range to obstacles and terrain. This biologically inspired approach is applied to control of height in a helicopter, leading to the World’s first optic flow based terrain following controller for an unmanned helicopter in forward flight. Another novel optic flow based controller is developed for the control of velocity in hover. Using the measurements of height from other sensors, optic flow is used to provide a measure of the helicopters lateral and longitudinal velocities relative to the ground plane. Feedback of these velocity measurements enables automated hover with a drift of only a few cm per second, which is sufficient to allow a helicopter to land autonomously in gusty conditions with no absolute measurement of position.¶ New techniques for sensor fusion using Extended Kalman Filtering are developed to estimate attitude and velocity from noisy inertial sensors and optic flow measurements. However, such control and sensor fusion techniques can be computationally intensive, rendering them difficult or impossible to implement on a small unmanned vehicle due to limitations on computing resources. Since neural networks can perform these functions with minimal computing hardware, a new technique of control using neural networks is presented. First a hybrid plant model consisting of exactly known dynamics is combined with a black-box representation of the unknown dynamics. Simulated trajectories are then calculated for the plant using an optimal controller. Finally, a neural network is trained to mimic the optimal controller. Flight test results of control of the heave dynamics of a helicopter confirm the neural network controller’s ability to operate in high disturbance conditions and suggest that the neural network outperforms a PD controller. Sensor fusion and control of the lateral and longitudinal dynamics of the helicopter are also shown to be easily achieved using computationally modest neural networks.

Ce travail de recherche est axé sur l'étude des instabilités gravitaires dans les Pyrénées et sur le rôle des facteurs géologiques, hydrogéologiques et mécaniques dans le déclenchement des glissements de terrain. Cette réflexion est menée à travers l'étude de deux types différents de glissements de terrain : l'un en milieu rocheux, l'autre en milieu granulaire. Dans le premier cas il s'agit du glissement rocheux historique de Pleysse datant de 1982 et situé en Vallée d'Ossau, dans l'autre cas il s'agit du glissement de Gouetsoule activé en 1997 et localisé en Vallée d'Aspe. Au terme de ce travail, les différents facteurs géologiques, hydrogéologiques et mécaniques ont été définis pour chaque glissement de terrain afin de déterminer les facteurs déclenchants. Leurs études ont aussi permis d'améliorer la compréhension d'une instabilité gravitaire tant en milieu granulaire que rocheux.

La présente thèse est divisée en deux parties. La première est relative à la méthode d'étude et la seconde est consacrée à divers exemples d 'application de cette méthode et de traitements des glissements de terrains. La première partie comprend cinq chapitres portant respectivement sur les différentes classes de mouvements, la présentation de la méthode d' étude, la classification des causes , les méthodes d'investigation dont on dispose et enfin les remèdes . La classification proposée au chapitre l ne prétend pas annuler les précédentes et en particulier celle de J-P. BOMBA RD (1968). Elle a pour but de regrouper les différentes classes de mouvements en fonction de deux critères géométriques. la présence ou l'absence de surface de glissement définie et l'intensité de la déformation interne. Dans les quatre chapitres suivants, on étudiera les problèmes posés par les mouvements de terrains à l'aide d 'une logique fondée sur les méthodes de la mécanique. Le deuxième chapitre sera consacré à la description de cette méthode d'étude (méthode rigoureuse) et à la traduction pratique des paramètres et relations à connaître pour traiter ces problèmes de glissements. On examinera aussi quelles sont les méthodes de calcul employées actuellement (la discussion de leur validité pour représenter la réalité n'est pas le but du présent travail; elle fera l 'objet d 'une autre thèse: celle de J-P. MOUGIN) . effectivement connaître des paramètres et relations définis au chapitre Il, les trois derniers chapitres seront consacrés à une méthode d'étude pratique. fondée en grande partie sur les expériences relatées par divers auteurs ainsi que sur les nôtres . Le troisième chapitre traitera des causes des mouvements, telles qu 'on peut les grouper en partant de la logique qui nous guide. Le quatrième chapitre sera consacré aux méthodes d'investiga tion dont on dispose à présent pour connaître les paramètres nécessaires à l' étude. Il comportera également une méthode d'utilisation des résultats pour tenter de prévoir l'imminence d'un danger. Enfin, le cinquième chapitre sera une revue des remèdes utilisables pour enrayer ces mouvements. La deuxième partie comportera quelques exemples de glissements : - le glissement de Vajont - Longarone où de nombreuses études avaient été effectuées - le glissement de G. L ... est un problème de stabilité de berge de retenue. Les études sont en cours; - le cas de L ... concerne une route et tous les problèmes de stabilité afférents - le glissement de Montmélian est un exemple de stabilisation. En conclusion, la présente étude ne peut prétendre résoudre tous les problèmes posés par les glissements, car certaines données sont actuellement encore imprécises . Elle aura néanmoins atteint son but si elle peut permettre de clarifier le problème et de l'aborder méthodiquement.

Comportement différé, anisotrope à la descenderie de Saint-Martin-la-Porte

In this report we describe simulation of the surface current density on a PEC cylinder and the diffracted field for a line source above a finite PEC ground plane as a means to verify the Nero2D program. The results are compared with the exact solution and give acceptable errors. A terrain model for a communication link is studied in the report and we simulate the wave propagation for terrain with irregular shapes and different materials. The Nero2D program is based on the fast multipole method (FMM) to reduce computation time and memory. Gaussian sources are also studied to make the terrain model more realistic

This thesis describes a novel terrain synthesis method based on distances in a weighted graph. The method begins with a regular lattice with arbitrary edge weights; heights are determined by path cost from a set of generator nodes. The shapes of individual terrain features, such as mountains, hills, and craters, are specified by a monotonically decreasing profile describing the cross-sectional shape of a feature, while the locations of features in the terrain are specified by placing the generators. Pathing places ridges whose initial location have a dendritic shape. The method is robust and easy to control, making it possible to create pareidolia effects. It can produce a wide range of realistic synthetic terrains such as mountain ranges, craters, faults, cinder cones, and hills. The algorithm incorporates random graph edge weights, permits the inclusion of multiple topography profiles, and allows precise control over placement of terrain features and their heights. These properties all allow the artist to create highly heterogeneous terrains that compare quite favorably to existing methods.

In an existing process, Rapid 3D Mapping datasets are automatically generated and converted to a format suitable for simulators and mission support systems. However, this high level automation does not allow manual error fixes and the addition of important features to the map data. The aim of this thesis is to create a process that allows the editing of a number of R3DM tiles with an existing 3D modeling tool and, after editing, to propagate the changes to the lower levels of detail in the data. Two solutions for the propagation, a standard solution and an alternative, are presented in this thesis. The motivation behind the alternative solution is to keep the original geometry of the R3DM data to retain the good rendering performance which those data sets permit. To achieve this the new model will be added to the R3DM data at only the highest level of detail, and this model is then simplified before propagation to the lower levels of detail. The resulting procedure to fix errors and add new important features is very effective, and reduces the time required for users to edit the many levels of the R3DM data.

Understanding the hydrology of the riparian zone in a catchment can be an important prerequisite for determining solute loads and concentrations in streams. The riparian zone is the transition zone between surrounding landscape and an open water stream. This study focuses on the spatial and temporal variations of shallow groundwater levels in a forested headwater catchment in the Bergslagen area of central Sweden. Three snapshot campaigns were conducted during dry, humid and wet conditions to map the spatial variability of the groundwater levels. Piezometers giving the total hydraulic head were placed in the riparian zone along a stream network consisting of three first order streams and one second order stream. To asses temporal variations five groundwater wells were installed with automatic loggers to record continuous data during the wet period. Historical streamflow records from a permanent field station were collected and related to the groundwater levels in order to assess the relationship between groundwater levels and streamflow. Additionally a landscape analysis using GIS methods was conducted in order to identify potential drivers of spatial variation of groundwater levels in the riparian zone. The results showed that the slope could partially explain the observed spatial variability of riparian groundwater levels. The results from the spatially distributed piezometers and the continuously monitored groundwater wells with loggers were contradicting. Where the piezometers showed increasing depth to the groundwater table with increasing slope the loggers indicated the opposite. However, because the piezometers outnumbered the loggers the piezometer results can be considered more representative of the spatial variation of groundwater levels. There could be no general result concluded on the catchment scale but when looking at specific subcatchments it could be found that the variations in the riparian groundwater levels could be better explained where the stream had a more distinct channel. This indicates the importance to evaluate not only slope but the profile curvature as well for groundwater predictions.

This thesis describes a novel terrain synthesis method based on distances in a weighted graph. The method begins with a regular lattice with arbitrary edge weights; heights are determined by path cost from a set of generator nodes. The shapes of individual terrain features, such as mountains, hills, and craters, are specified by a monotonically decreasing profile describing the cross-sectional shape of a feature, while the locations of features in the terrain are specified by placing the generators. Pathing places ridges whose initial location have a dendritic shape. The method is robust and easy to control, making it possible to create pareidolia effects. It can produce a wide range of realistic synthetic terrains such as mountain ranges, craters, faults, cinder cones, and hills. The algorithm incorporates random graph edge weights, permits the inclusion of multiple topography profiles, and allows precise control over placement of terrain features and their heights. These properties all allow the artist to create highly heterogeneous terrains that compare quite favorably to existing methods.