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Soliman, Mohamed Samir Abdel Latif. "Microwave techniques for the detection of buried objects." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493532.
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Ground Penetrating Radar (GPR) is an active and non-invasive exploration technique based on the propagation of electromagnetic waves in the subsurface. Developing new and simple algorithms to improve the GPR performance is important because it helps to interpret the data received by the GPR. This leads to the basis (solution to the forward problem) for most iterative inversion techniques. Conversely, imaging is a type of inversion technique (backward propagation) that creates an image related to the subsurface reflectivity. However, for practical applications, imaging techniques must be fast, accurate and efficient.
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Norville, Pelham D. "Time-Reversal Techniques in Seismic Detection of Buried Objects." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14475.
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An investigation is presented of the behavior of time-reversal focusing in soils. Initial numerical models demonstrate time-reversal focusing to be effective in elastic media, including when a large number of scattering objects were present in the medium. When scattering objects are present, time-reversal focusing demonstrates superior focusing ability when compared to other excitation methods such as uniform excitation or time-delay focusing.
Multiple experimental investigations of experimental time-reversal focusing performed in sand evaluate time-reversal focusing effectiveness when multiple near-surface scattering objects are present in the medium. Experimental results demonstrate that time-reversal focusing is effective in the experimental context as well as the numerical models. Further experiments examine time-reversal focusing in more extreme cases where the entire
ballistic wave is blocked, and the only energy reaching the focus point is reflected from scattering objects in the medium. A comparison to other focusing methods demonstrates that under these conditions, most focusing attempts with traditional methods will fail completely while time-reversal focusing does not. Additional configurations of time-reversal focusing examine its effectiveness when scattering is caused by an asymmetrical surface layers. The impact of an asymmetrical or non-uniform excitation array is also examined for time-reversal focusing in the presence of scattering objects.
An investigation of the effects of scattering object geometry on focusing resolution in time-reversal focusing is also presented. Scattering object field density is found to have a strong, but diminishing effect on focusing resolution as the scattering object field density increased. Loss of surface wave energy available for focusing due to mode-conversion is found to be correlated with the density of the scattering object field.
The impact of the weak non-linear nature of the soil on time-reversal focusing is examined through a study of time-reversal focusing behavior for a variety of amplitudes that generate different levels of non-linearity in the soil. This study of nonlinearity is coupled with a study of the impact of noise on time-reversal focusing. It appears that both non-linearity and noise have an impact on time-reversal focusing effectiveness. Further, the loss from these mechanisms seems to be interrelated. Noise seems to enhance non-linear loss in the soil.
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Edwards, Joseph Richard 1971. "Acoustic classification of buried objects with mobile sonar platforms." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37568.
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Thesis (Ph. D. in Ocean Engineering)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references (p. 229-237).
In this thesis, the use of highly mobile sonar platforms is investigated for the purpose of acoustically classifying compact objects on or below the seabed. The extension of existing strategies, including synthetic aperture sonar and conventional imaging, are explored within the context of the buried object problem. In particular, the need to employ low frequencies for seabed penetration is shown to have a significant impact both due to the relative length of the characteristic scattering mechanisms and due to the interface effects on the target scattering. New sonar strategies are also shown that exploit incoherent wide apertures that are created by multiple sonar platforms. For example, target shape can be inverted by mapping the scattered field from the target with a team of receiver vehicles. A single sonar-adaptive sonar platform is shown to have the ability to perform hunting and classification tasks more efficiently than its pre-programmed counterpart. While the monostatic sonar platform is often dominated by the source component, the bistatic or passive receiver platform behavior is controlled by the target response. The sonar-adaptive platform trajectory, however, can result in the platform finishing its classification effort out of position to complete further tasks.
(cont.) Within the context of a larger mission, the use of predetermined adaptive behaviors is shown to provide improved detection and classification performance while minimizing the risk to the overall mission. Finally, it is shown that multiple sonar-adaptive platforms can be used to create new sonar strategies for hunting and classifying objects by shape and content. The ability to sample the scattered field from the target across a wide variety of positions allows an analysis of the aspect-dependent behavior of the target. The aspect-dependence of the specular returns indicate the shape of the target, while the secondary returns from an elastic target are also strongly aspect-dependent. These features are exploited for improved classification performance in the buried object hunting mission.
by Joseph R. Edwards.
Ph.D.in Ocean Engineering
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Salucci, Marco. "Innovative inversion approaches for buried objects detection and imaging." Doctoral thesis, Università degli studi di Trento, 2014. https://hdl.handle.net/11572/368200.
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The study, development, and analysis of innovative inversion techniques for the detection and imaging of buried objects is addressed in this thesis. The proposed methodologies are based on the use of microwave radiations and radar techniques for subsurface prospecting, such as, for example, the Ground Penetrating Radar (GPR). More precisely, the reconstruction of shallow buried objects is firstly addressed by an electromagnetic inverse scattering method based on the integration of the inexact Newton (IN) method with an iterative multiscaling approach.
The performances of such an inversion approach are analyzed both when considering the use of a second-order Born approximation (SOBA) and when exploiting the full set of non-linear equations governing the scattering phenomena for the buried scenario. The presented methodologies are particularly suitable for applications such as demining (e.g., for the detection of unexploded ordnances, UXOs, and improvised explosive devices, IEDs), for civil engineering applications (e.g., for the investigation of possible structural damages, voids, cracks or water infiltrations in walls, pillars, bridges) as well as for biomedical imaging (e.g., for early cancer detection).
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Salucci, Marco. "Innovative inversion approaches for buried objects detection and imaging." Doctoral thesis, University of Trento, 2014. http://eprints-phd.biblio.unitn.it/1347/1/Ph.D.Thesis.SALUCCI-November.2014.FINAL.pdf.
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The study, development, and analysis of innovative inversion techniques for the detection and imaging of buried objects is addressed in this thesis. The proposed methodologies are based on the use of microwave radiations and radar techniques for subsurface prospecting, such as, for example, the Ground Penetrating Radar (GPR). More precisely, the reconstruction of shallow buried objects is firstly addressed by an electromagnetic inverse scattering method based on the integration of the inexact Newton (IN) method with an iterative multiscaling approach.
The performances of such an inversion approach are analyzed both when considering the use of a second-order Born approximation (SOBA) and when exploiting the full set of non-linear equations governing the scattering phenomena for the buried scenario. The presented methodologies are particularly suitable for applications such as demining (e.g., for the detection of unexploded ordnances, UXOs, and improvised explosive devices, IEDs), for civil engineering applications (e.g., for the investigation of possible structural damages, voids, cracks or water infiltrations in walls, pillars, bridges) as well as for biomedical imaging (e.g., for early cancer detection).
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Papandreou, Benjamin David. "On the detection of shallow buried objects using seismic wave reflections." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/334160/.
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This thesis is concerned with a methodology for the detection of shallow (of order 1 metre) objects buried in soil using seismic waves. Possible objects of interest include infrastructure, archaeological artefacts and ordinance. A mathematical analysis of an idealised system is performed to gain understanding of both seismic wave propagation and the generation of these waves by surface sources. The mathematical techniques used in the existing analysis of a point vertical source are applied to the desired problem of a point horizontal surface traction. Results are displayed in a graphically concise form. An experimental methodology, capable of forming two-dimensional images through the ground, is described. The use of shear waves is shown preferable. The advantages and implementation of using time extended, rather than impulsive, excitation signals are described. Additional signal processing techniques, such as generalised cross-correlation functions, are also detailed. Simple numerical simulations are undertaken with the aim of both validating the post-processing algorithms and evaluating its robustness against non-ideal conditions. Simulated time histories are created by defining signals in the frequency domain and then modifying their amplitude and phase to replicate attenuation and propagation. Non-ideal conditions focus mainly on variation in the wavespeed as a function of depth. Simulations indicate that the imaging method fails for sufficiently large variations of wavespeed, particularly for objects buried below significant discontinuities in material properties. As shear waves are used for the imaging method, a source was designed and constructed to preferentially generate shear waves and was verified using field experimentation. The imaging methodology is applied to data from three experimental sites and is able to detect the target objects with some success. Problems, however, remain with the measurement of a wavespeed that is consistent and indicative of the propagation speed at depth, and in consistently obtaining a sufficiently large reflected wave from the object.
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Hall, Patrick W. "Detection and target-strength measurements of buried objects using a seismo-acoustic sonar." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA359103.
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Thesis (M.S. in applied Physics) Naval Postgraduate School, December 1998."December 1998." Thesis advisor(s): Thomas G. Muir, Steven R. Baker. Includes bibliographical references (p. 59-60). Also available online.
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Bang, Gwan-Sik. "Localization of buried objects in water-saturated sand by variable incidence acoustic pulse reflections." Thesis, Washington, D.C. : Dumbarton Oaks Research Library and Collection ; [Cambridge, Mass.] : Distributed by Harvard University Press, 1985. http://hdl.handle.net/10945/21407.
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Cross, James. "Low-frequency electromagnetic fields for the detection of buried objects in the shallow sub-surface." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4996/.
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This thesis explores the application of low-frequency electromagnetic fields, which may be excited within a buried pipe, for the detection of underground utilities. Low-cost network analyser technology, which can be applied to field-measurements of the relative-permittivity of soil, is evaluated. These technologies are compared to laboratory-grade alternatives whose cost prohibits their use for field work. Methodologies for the measurement of the relative-permittivity of soil are discussed with reference to the low-cost technology, including use of a novel coaxial cavity which incorporates a step-discontinuity. It is shown that there is potential for use of low-cost network analysers in measuring relative-permittivity, but that further research is required to formulate a complete methodology. The propagation of electromagnetic waves in layered media is discussed. The recent literature relating to this field is extensively reviewed, with several errors and omissions highlighted. A new calculation is presented which allows the calculation of the electromagnetic field due to a vertical electric dipole in a four-layered medium. Example results, including an approximation of a leaking pipe, are presented. Finally, two sets of field trials are reviewed. The first field trials looked to observe waves propagating with low-velocity in the ground, by measuring the phase change along an array of receiving probes. Waves, propagating with low-velocity, were observed. However, direction of arrival measurements were not achievable due to a combination of signal-to-noise ratio, and the expected phase change at the observed propagation-velocity, across an array of realistic size. The second field trials measured low-frequency electromagnetic fields, excited within a buried pipe, which were used to detect the location of the pipe with good correspondence to the ground truth. Furthermore, comparison with a ground-penetrating radar survey indicated that some anomalous results in the low-frequency electromagnetic survey corresponded to shallow targets detected using ground-penetrating radar.
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Williams, Elizabeth S. "Upheaval buckling of offshore pipelines buried in loose and liquefiable soils." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:10c2cf4d-ab26-4f2c-82d9-35e15cfa03bc.
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Pipelines used for the transportation of oil and gas products offshore are often buried beneath the seabed for protection from mechanical damage and for thermal insulation. During high temperature and high pressure operations, these pipelines are susceptible to resurfacing behaviour known as upheaval buckling, a structural response that is strongly influenced by the resistance of the surrounding soil. Despite much previous research on pipe uplift, the influence of the initial soil state – particularly in loose and liquefiable soil conditions – on the uplift resistance and corresponding buckling behaviour of the pipe is not well understood. This thesis presents research that examines the implications of these backfill conditions in the context of the global behaviour of the pipeline. The work consists of plane-strain monotonic uplift experiments focusing on density, rate, and stress level effects on the initial pipe-soil response. This is followed by numerical modelling of the global buckling behaviour using the experimental data as inputs. Finally, plane-strain cyclic experiments examine the possibility of progressive upward displacements over a number of cycles causing eventual upheaval buckling. A key finding from the uplift tests is that very loose backfill conditions may result in a localised flow-around failure mechanism, associated with lower peak resistance and a softer force-displacement response than with the sliding block mechanism that is typically assumed. This leads to lower peak buckling loads/temperatures than those predicted by current design guidelines. High quality data from both the monotonic and cyclic experiments was used to assess and suggest improvements to design guidance for these conditions.
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Yalçıner, Cahit Çağlar. "Investigation of buried objects with Ground Penetrating Radar : application to archaeoseismology and palaeoseismology in the Buyuk Menderes Graben (Turkey)." Strasbourg, 2009. https://publication-theses.unistra.fr/public/theses_doctorat/2009/YALCINER_Cahit_Caglar_2009.pdf.
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L’Anatolie occidentale est une des régions les plus sismiquement actives du monde, comme en attestent les structures actives en horst et graben qui la délimitent. La présente étude est focalisée sur le Fossé de Büyük Menderes, une structure majeure qui s'étend de la Mer Egée à l’ouest jusqu’au Bassin de Denizli à l’est. Une cartographie de détail montre que les failles actives qui forment la limite nord du graben ont produit des séismes durant la période historique. Ces ruptures ont été décrites en détail lors de campagnes de terrain. Lorsque l’observation directe s’est révélée impossible, nous avons eu recours à la prospection géophysique par géoradar. La méthode géoradar s’appuie sur l’émission active puis l’enregistrement d’ondes électromagnétiques réfléchies par les différentes interfaces du sous-sol. Les données sont enregistrées puis filtrées afin d’éliminer le bruit environnemental et instrumental puis interprétées pour identifier les structures enfouies avec une haute résolution et une grande sensibilité. Dans le cadre de ces travaux, des campagnes d’acquisition GPR ont été réalisées sur six sites différents : deux tranchées, trois sites archéologiques affectés par des failles et un site archéologique enterré. En amont de toute campagne d’excavation, nous avons ainsi pu déterminer la géométrie de la trace de la faille, la largeur de la zone de faille ainsi que la quantité de déplacement affectant les unités récentes. A l’un des sites, des structures archéologiques portent la trace de mouvements récents le long d’une faille. La géométrie de la faille tout comme la largeur de la zone de déformation ont été définies, ainsi que le déplacement total qui correspond aux mesures de surface. Les travaux de tranchée, réalisés sur la base des résultats du géoradar, ont révélé des quantités de déplacement co-sismique cumulé très comparables aux quantités déterminées par le géoradar. D’autre part, la trace de faille identifiée dans les profiles géoradar correspond bien, en profondeur, à des décalages de structures archéologiques. Ainsi, sur le site de la ville antique de Nysa, les mesures destinées à détecter le passage de l’ancienne route d’accès à la ville, le géoradar a révélé des déplacements affectant un temple jusqu’ici inconnuWestern Anatolia is one of the most active regions in the world and is represented by horsts and grabens faulted on the margins. The subject of this work, the Büyük Menderes graben, is one of the most active structures in the region and extends between the Aegean Sea in the west and the Denizli Basin in the east. Detailed mapping shows that the active faults bounding the northern boundary of the graben were ruptured with surface breaks in historical periods. These ruptures identified in detail during the field studies. Where direct observations were not possible, however, the characteristic features of the faults were identified by using the Ground Penetrating Radar (GPR), one of the shallow geophysical methods. The GPR method works on the basis of recording of the reflections of the electromagnetic waves from the interfaces by a horizontal receiver which were transmitted to the ground with high velocity by using a horizontal antenna. Data collected is filtered to eliminate the environmental and instrumental noise by using computers and then interpreted to determine the buried structures in high resolution and sensitivity. In scope of the investigation, GPR studies were conducted in six different locations (two trenches, three faulted archaeological site and a buried archaeological site). The trace of the fault, width of the fault zone and the amount of the offset of the young units along the fault were determined by the GPR method before the excavation of the trenches. In the archaeological site where the offset remnants of the archaeological objects were observed, the trace of the faults and the width of the deformational zones were determined by the GPR and the amount of offset obtained from GPR profiles were compared with the offset amounts measured on the surface. In order to locate the exact location of the ancient road entering the ancient Nysa town GPR, studies were conducted and a previously unknown temple was discovered. In the trenches which were excavated based on the GPR findings, it was found that the amount of the offset obtained by the GPR method and the actual offset measured on the trench wall were agreeable with each other. Where the offset archaeological structures exist, it was observed that the faults on the GPR profiles correspond to the ruptures on these structures. In Nysa ancient town, the image obtained from GPR was interpreted to belong to a structure rather than the road expected; in fact, the excavations conducted later on revealed a temple which was not known to exist before
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Yalçıner, Cahit Çağlar Meghraoui Mustapha Bano Maksim Altunel Erhan. "Investigation of buried objects with Ground Penetrating Radar Application to archaeoseismology and palaeoseismology in the Buyuk Menderes Graben (Turkey) /." Strasbourg : Université de Strasbourg, 2009. http://eprints-scd-ulp.u-strasbg.fr:8080/1123/01/YALCINER_Cahit_Caglar_2009.pdf.
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Thèse de doctorat : Sciences de la Terre. Géophysique, Proche Surface : Strasbourg 1 : 2009. Thèse de doctorat : Sciences de la Terre. Géophysique, Proche Surface : Université Eskişehir Osmangazi, Turquie : 2009.Thèse soutenue sur un ensemble de travaux. Thèse soutenue en co-tutelle. Titre provenant de l'écran-titre. Bibliogr. 13 p.
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Lepper, Paul Andrew. "The development and testing of a parametric sonar system for use in sediment classification and the detection of buried objects." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/32977.
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This thesis describes the work carried out in the development and testing of parametric sonar systems for application in the fields of seabed sediment characterisation and classification, and the detection of seabed embedded objects. Parametric sonar systems offer a number of advantages over conventional sonar systems. This is especially true of the conflicting requirements of both seabed delineation and penetration required for a practical sub-seabed profiling system. Echoes from sub-bottom layers vary in strength dependent on both the boundary acoustic reflectivity and the absorption characteristics of the layer above. Absorption effects are usually frequency dependent, allowing better penetration to lower frequency signals.
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Stewart, William F. "Buried object detection using surface waves /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA305744.
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Thesis (M.S. in Engineering Acoustics) Naval Postgraduate School, September 1995."September 1995." Thesis advisor(s): Anthony A. Atchley. Includes bibliographical references. Also available online.
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Pierson, David Michael. "Buried-Object Detection Using Time-Reversed Acoustics." NCSU, 2004. http://www.lib.ncsu.edu/theses/available/etd-01122004-083659/.
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The work presented here is a comprehensive study of using time reversal to detect objects located in an inhomogeneous environment using backscattered signals with an emphasis on littoral environments. Time reversal of acoustic signals in the ocean has been studied for more than two decades with the emphasis on the use of the forward scattered field. All studies share similar geometries where both the acoustical source and an adjacent array of transducers are placed in the water column. This configuration, known as a time-reversal mirror (TRM), is not practical when detecting an object that is located in a different environment than the TRM, such as beneath the ocean floor. Little work has been done to study the efficacy of a single transceiver performing the time-reversal operation on the backscattered signals from targets buried beneath the ocean floor. Here, I start by presenting the theory for such a system in both time and frequency domains for scattering by a sphere. Then by using simulations I show that time reversal of backscattered signals provides a robust method to detect targets buried in an acoustically inhomogeneous sediment using a point transceiver in the water column several meters above the sea floor. Effects of the time-reversal window (TRW) on the iterative time-reversal operation are also presented. I define a signal-to-noise ratio (SNR) that treats the return with the sphere as the signal and the return without the sphere as noise to quantify improvements to the sphere returns. I consider two different sediment models and angle of incidence to show that the TRO operates independently of the sediment type and transceiver orientation. Theoretical analysis reveals that the time-reversal of backscattered signals converges to a subset of waveforms defined by the target and time-reversal window, not the initial pulse. Analysis further reveals that the time-reversal operator detects the sphere after only two iterations of the TRO, with more iterations enhancing the sphere return through the non-linear filtering property of the TRO. Through this work, I demonstrate that time reversal is a robust method to detect objects.
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Han, Dong. "Caractérisation des objets enfouis par les méthodes de traitement d'antenne." Thesis, Aix-Marseille 3, 2011. http://www.theses.fr/2011AIX30003/document.
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Cette thèse est consacrée à l'étude de la localisation d'objets enfouis dans acoustiques sous-marins en utilisant les méthodes de traitement d'antenne et les ondes acoustiques. Nous avons proposé un modèle bien adapté en tenant compte le phénomène physique au niveau de l'interface eau/sédiment. La modélisation de la propagation combine donc la contribution de l'onde réfléchie et celle de l'onde réfractée pour déterminer un nouveau vecteur directionnel. Le vecteur directionnel élaboré à partir des modèles de diffusion acoustique est utilisé dans la méthode MUSIC au lieu d'utiliser le modèle d'onde plane habituel. Cette approche permet d'estimer à la fois coordonnées d'objets (angle et distance objet-capteur) de forme connue, quel que soit leur emplacement vis à vis de l'antenne, en champ proche ou en champ lointain. Nous remplaçons l'étape de décomposition en éléments propres par des algorithmes plus rapides. Nous développons un algorithme d'optimisation plus élaboré consiste à combiner l'algorithme DIRECT (DIviding RECTangles) avec une interpolation de type Spline, ceci permet de faire face au cas d'antennes distordues à grand nombre de capteurs, tout en conservant un temps de calcul faible. Les signaux reçus sont des signaux issus de ce même capteur, réfléchis et réfractés par les objets et sont donc forcément corrélés. Pour cela, nous d'abord utilisons un opérateur bilinéaire. Puis nous proposons une méthode pour le cas de groupes indépendants de signaux corrélés en utilisant les cumulants. Ensuit nous présentons une méthode en utilisant la matrice tranche cumulants pour éliminer du bruit Gaussien. Mais dans la pratique, le bruit n'est pas toujours gaussien ou ses caractéristiques ne sont pas toujours connues. Nous développons deux méthodes itératives pour estimer la matrice interspectrale du bruit. Le premier algorithme est basé sur une technique d'optimisation permettant d'extraire itérativement la matrice interspectrale du bruit de la matrice interspectrale des observations. Le deuxième algorithme utilise la technique du maximum de vraisemblance pour estimer conjointement les paramètres du signal et du bruit. Enfin nous testons les algorithmes proposés avec des données expérimentales et les performances des résultats sont très bonnesThis thesis is devoted to the study of the localization of objects buried in underwater acoustic using array processing methods and acoustic waves. We have proposed a appropriate model, taking into account the water/sediment interface. The propagation modeling thus combines the reflected wave and the refracted wave to determine a new directional vector. The directional vector developed by acoustic scattering model is used in the MUSIC method instead of the classical plane wave model. This approach can estimate both of the object coordinates (angle and distance sensor-object) of known form, in near field or far field. We propose some fast algorithms without eigendecompostion. We combine DIRECT algorithm with spline interpolation to cope with the distorted antennas of many sensors, while maintaining a low computation time. To decorrelate the received signals, we firstly use a bilinear operator. We propose a method for the case of independent groups of correlated signals using the cumulants. Then we present a method using the cumulants matrix to eliminate Gaussian noise. But in practice, the noise is not always Gaussian or the characteristics are not always known. We develope two iterative methods to estimate the interspectral matrix of noise. The first algorithm is based on an optimization technique to extract iteratively the interspectral matrix of noise. The second algorithm uses the technique of maximum likelihood to estimate the signal parameters and the noise. Finally we test the proposed algorithms with experimental data. The results quality is very good
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PEI, YUEKUN. "GNSS Reflectometry for land surface monitoring and buried object detection." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2586356.
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Global Navigation Satellite System Reflectometry (GNSS-R) is attracting growing interest nowadays for several remote sensing applications. As a bistatic radar, the transmitter and the receiver are not co-located and in the special case of GNSS-R, the GNSS satellites are acting as transmitters and the receiver can be mounted either in a static position or onboard a aircraft or low orbit satellite. Various information about the surface from where the GNSS signals are reflected or scattered can be extracted by means of reflected signal strength, code delay, carrier phase delay, interference with direct GNSS signals and so on. Possible applications cover soil moisture retrieval, ice topography and thickness detection, snow depth estimation, vegetation coverage, sea state monitoring such as sea wind and surface roughness, sea salinity…
In this work, soil moisture retrieval was mostly focused on. Hardware including antennas and receivers was studied and designed. Our first strategy of soil moisture retrieval is to apply a single Left Hand Circular Polarization (LHCP) antenna for reflected signal reception. Therefore multiple types of antennas such as the helix antenna, the patch antenna and several commercial antennas were designed, simulated or tested in the anechoic chamber. Two receiver solutions were used in our group and both of them apply the SiGe GPS frontend. The first solution is a PC based one: the collection and store of the raw incoming reflected GPS signals were done by the NGrab software (designed by NAVSAS Group of Politecnico di Torino) installed in a standard PC. The other solution was developed in our group and it is operated by a single Hackberry board, which consists of power supply, storage subsystem and customized Linux Debian operating system. The light weight and small size enable this compact receiver to perform flight measurement onboard UAVs.
Both of the above mentioned receivers only store raw sampled data and no real time signal processing is performed on board. Post processing is done by Matlab program which makes correlations in both time and frequency domain with incoming signals using the local generated GPS C/A code replica. The so-called Delay Doppler Map (DDM) is therefore generated through this correlation. Signal to Noise Ratio (SNR) can be calculated through Delay Waveform (DW) which is extracted from DDM at the Doppler frequency where the correlation peak exists. Received signal power can be obtained knowing the noise power which is given in a standard equation. In order to better plan a static measurement and to georeference specular points on the surface, programs for georeferencing specular points on either Google Maps or an x-y plane centered at the receiver position were developed. Fly dynamics in terms of roll, pitch and yaw influencing the antenna gain due to the variation of incident angles were also studied in order to compensate the gain to the received signal.
Two soil moisture retrieval algorithms were derived corresponding to two receiving schemes. The first one is for the receiving of only LHCP reflected signals. In this case, the surface is assumed to be perfectly smooth and the received signal is seen to consist of only coherent component caused by specular reflection. Dielectric constant can be retrieved from the processed SNR. Two measurement campaigns were carried out using this single LHCP system. The first campaign is a flight measurement overflown a big portion of rice fields when most of the fields were flooded. It was a test measurement on the SNR sensitivity to water/no-water surfaces and an attempt of dielectric constant retrieval was also performed. SNR showed good sensitivity to the surface water content and dielectric constant was also checked to be reasonable. The second campaign is in static positions and it includes two experiments. This campaign initially aimed at testing the sensitivity of the compact receiver to different surface moisture. Results of both SNR and retrieved dielectric constant showed to be coherent with the surface moisture changes.
The other retrieval algorithm is for the receiving of both LHCP and RHCP reflected signals concurrently. The cross polarization power ratio (LHCP/RHCP) is believed to be independent of surface roughness by several previous studies and this idea was also verified during the deriving process for either specular reflection case (only coherent component) or diffuse scattering condition (incoherent component). For diffuse scattering, three well known models were applied which are the Kirchhoff Approximation in stationary-phase approximation (Kirchhoff Geometrical Optics, KGO), Kirchhoff Approximation in Physical Optics Approximation (KPO) and Small Perturbation Method (SPM). These three models cover different roughness surfaces from very rough (KGO) to slightly rough surfaces (SPM). All the derived results of cross polarization ratio for the three models were verified to be independent of surface properties and depend on only dielectric constant of soil and incident angle.
A new application of GNSS-R technique for the possibility of detection of buried objects was firstly investigated by our group. It has the potential use for man-made mines detection in the military field. Two measurement campaigns were carried out and the variation of the SNR level due to the presence of a metallic object was investigated. The first measurement campaign was performed in a static condition on a sandy terrain to check the functionality of the system. And the presence of the metallic object was detected also in the case of wet terrain. In the second measurement campaign, the antenna was moving along a given path and the possibility of detecting the object dimensions was highlighted. The results show the possibility of adopting this technique on board a remotely controlled UAV for metal object and even its dimension detection.
A measurement of snow depth attempting to relate it to reflected LHCP SNR is briefly presented and discussed in Chapter 7.
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Mazzolo, Lisa-Marie. "Étude et développement d’un outil efficace de simulation pour l’évaluation de SER : Application à la détection d’objets enfouis à partir de plates-formes aéroportées." Electronic Thesis or Diss., Toulouse, ISAE, 2024. http://www.theses.fr/2024ESAE0047.
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La détection d'objets enfouis, qu'il s'agisse d'engins explosifs dans un contexte militaire ou de structures archéologiques dans un contexte civil, constitue une préoccupation majeure. En termes de télédétection radar, les systèmes aéroportés, comme le radar à synthèse d’ouverture (SAR), permettent une imagerie non destructive des sous-sols tout en offrant la possibilité d'explorer de vastes zones avec une distance de sécurité par rapport à celles-ci. Cependant, leur efficacité pour la détection d’objets enfouis dépend de nombreux facteurs, tels que les caractéristiques diélectriques du sol, qui affectent la profondeur de pénétration des ondes électromagnétiques, la nature des cibles, le type d'émetteur... Une étude préliminaire, permettant de prédire la réponse des cibles en fonction des caractéristiques des systèmes et de la scène, serait alors un outil précieux pour évaluer les capacités de détection avant d'engager des campagnes de mesures.Cette thèse s'inscrit dans ce contexte, en se concentrant sur la recherche, le développement et l'optimisation d'un outil de simulation numérique destiné à évaluer précisément la surface équivalente radar (SER) d'objets enfouis. L'approche proposée repose sur une stratégie d'hybridation de solveurs FVTD (Finite Volume Time Domain) appliquée à des maillages hybrides cartésiens / non-structurés dans l'optique d'optimiser les coûts de calcul. En particulier, ces maillages hybrides permettent une représentation conforme des géométries courbes et une discrétisation spatiale localement adaptée aux vitesses de propagation des ondes électromagnétiques dans les différents milieux de la scène de calcul. La procédure d'obtention de ces maillages, basée sur le découpage du domaine de calcul en sous-domaines est détaillée, et les solveurs FVTD utilisés sont décrits en soulignant les choix effectués pour optimiser leur efficacité. L'implémentation des modèles permettant une description représentative du sol, la prise en compte précise d'une source de type onde plane et le calcul de champs lointains en présence d'un milieu avec pertes, est également abordée. L'hybridation des solveurs FVTD via une stratégie multi-domaines / multi-méthodes est présentée en détail, en mettant l'accent sur l'architecture logicielle proposée et en précisant la stabilité de la solution hybride ainsi que les enjeux de l'hybridation. Enfin, une comparaison de résultats simulés avec des données expérimentales obtenues dans le cadre d'une campagne de mesures mise en œuvre pour cette thèse, fournit une première appréciation des performances de l'outil de simulation développé. Pour conclure, la thèse met en avant la possibilité d'utiliser cet outil pour étudier l'impact des paramètres de configuration des systèmes radar sur la SER d'objets enfouis pour des scénarios donnésThe detection of buried objects, whether explosive devices in a military context or archaeological structures in a civilian context, is a major concern. In radar remote sensing, airborne systems such as Synthetic Aperture Radar (SAR) allow non-destructive imaging of subsurface environments while offering the possibility of exploring large areas from a safe distance. However, their effectiveness in detecting buried objects depends on many factors, such as the dielectric properties of the soil, which affect the penetration depth of electromagnetic waves, the nature of targets, and the type of transmitter... A preliminary study that predicts target response based on system and scene characteristics would be a valuable tool for assessing detection capabilities before launching measurement campaigns.This thesis addresses such context by focusing on the research, development, and optimization of a numerical simulation tool designed to accurately evaluate the radar cross-section (RCS) of buried objects. The proposed approach is based on a hybridization strategy using Finite Volume Time Domain (FVTD) solvers applied to hybrid Cartesian/unstructured meshes to optimize computational costs. More specifically, these hybrid meshes allow for a conformal representation of curved geometries and spatial discretization adapted to the varying electromagnetic wave propagation speeds in different media. The procedure for generating these meshes, based on the subdivision of the computational domain into subdomains is detailed, and used FVTD solvers are described, highlighting the choices made to optimize their efficiency. The implementation of models for representative soil description, accurate handling of plane-wave sources, and far-field calculations in lossy media are also addressed. The hybridization of FVTD solvers through a multi-domain/multi-method strategy is presented in detail, emphasizing proposed software architecture, the stability of the hybrid solution, and the challenges of hybridization. Finally, a comparison of simulated results with experimental data obtained during a measurement campaign conducted for this thesis provides an initial assessment of the performance of developed simulation tool. In conclusion, this thesis highlights the potential of this tool in studying the impact of radar system configuration parameters on buried objects RCS in given scenarios
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Battle, Katherine Elizabeth. "The burden of Plasmodium vivax malaria." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:ae06b0cb-14bc-44f7-acbe-e98e6c42867e.
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Plasmodium vivax is the most geographically widespread of the human malarias and is capable of causing severe debilitating disease. The parasiteâs unique biology poses challenges to control of the disease and the understanding of its epidemiology. It is less researched and well understood than the more deadly P. falciparum. In this thesis, spatial relapse patterns and models of endemicity and clinical disease were applied to generate robust estimates of the P. vivax burden to address a key knowledge gap in malaria epidemiology. First, a review of the distribution of the parasite, its vectors and populations at risk found nearly one third of the global population living at risk, and more potential vectors than P. falciparum. In spite of low observed endemicity, the public health impact of P. vivax is likely to have been seriously underestimated in the past. To accurately define the burden of P. vivax it was necessary to improve understanding of one of the parasiteâs most unique and challenging aspects, its ability to relapse. A meta-analysis of individual records of relapse showed that relapse periodicity varied systematically by geographic region and could be categorized by nine global regions. The nine regions were applied to a model to quantify the relationship between prevalence of infection and incidence of clinical disease. As relapse would have an influence on both measures, separate relationships were drawn for each relapse zone. The prevalence-incidence model was used to translate maps of predicted endemicity into measures of clinical burden. The evidence-base of P. vivax prevalence was poor in some regions and therefore a burden estimate based on surveillance reports was also derived. Reported cases must be adjusted for parameters such as under-reporting and treatment-seeking behaviours. A model used to fill gaps in treatment-seeking data available from national household surveys was developed to allow burden to be estimated using both cartographic modelling and surveillance reporting methods. To improve fidelity, the results of the two approaches were combined to enumerate P. vivax burden globally. The results and conclusions of these studies are discussed with recommendations for how these findings influence our understanding of P. vivax epidemiology and implications for future control and elimination efforts.
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Varkouhi, Shahab. "Biogenic silica diagenesis under early burial in hemipelagic marine sediments." Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:c7d3f4d9-0b43-41f6-9ce4-626aa27320bb.
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Four aspects of biogenic silica diagenesis are researched under this project: signatures of ongoing silica diagenesis in pore water, drivers leading to anomalous compaction (abrupt petrophysical changes), bottom-water temperature controls on silica dissolution and recycling, and temperature-time relationships in silica later diagenesis. Results of this project are discussed in Chapters 4-7. Chapter 4 demonstrates, based on pore chemistry, mineralogy, and thermodynamic analyses, that solubility equilibrium is reached for diagenetic silica in pore water at opal-A to opal-CT transition zone captured by Ocean Drilling Program Sites 794 and 795 in Japan Sea; thus opal-CT is precipitating across the transition. It is also argued that ion transport mechanisms have failed to erase signatures of ongoing diagenesis. Chapter 5 utilises texture and mineralogical analyses of hemipelagic sediments from Sites 794 and 795 to place anomalous compaction across the transition zone in a diagenetic context. A sharp decrease in opal-A content in the transition under dissolution causes a significant decrease in sediment stability which results in a porosity drop and other petrophysical variations. Subsequent precipitation of opal- CT has, however, had far less effects on porosity. Chapter 6 models variations in silica dissolution and recycling with bottom-water temperatures using data from 22 representative Ocean Drilling Program sites. Though model expression of early diagenesis confirms a relationship between temperature and opal-CT formation in young sediments (< 4 Ma) near the seabed in the Antarctic, the established inverse temperature-time correlation in silica diagenesis contradicts main controls from low bottom temperature over a short geological time. Chapter 7 investigates temperature-time relationships in silica diagenesis by examining 67 scientific drill sites where the opal-A to opal-CT transition zone lies in Cenozoic sediments. Based on these constraints, the reference opal-CT stability field is modified. The chapter also applies a model that formulates time-temperature dependence of silica diagenesis in representative Sites 794 and 795.
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Metzger, Ernest Philip. "The judge's burden : a new outline of the Roman civil trial." Thesis, University of Oxford, 1995. https://ora.ox.ac.uk/objects/uuid:a081af0d-a928-4ace-95b3-3da5415c3379.
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The subject of this thesis is the Roman civil trial before a single judge. This study was prompted by a recent archaeological discovery of great importance. The discovery of a municipal charter in Spain from the first century A.D. has revealed an enormous amount of detailed information on how a lawsuit during the classical period passed through its various stages, a subject on which previously we were very poorly informed. This thesis examines the new material in an effort to learn how a trial commenced and how a judge brought it to a close. The first half of the thesis discusses intertium, an institution previously unknown. It is suggested that intertium was a device by which a person selected to serve as judge was examined for suitability. The examination was undertaken immediately before the trial, to ensure that the lawsuit would not be suspended or fail for want of a judge. The second half of the thesis discusses adjournment and judgement. The new evidence suggests that the pertinent rules took great care to distinguish a judge's failure to serve from the proper suspension of the trial by adjournment. A judge might therefore negotiate the rules with little difficulty, and bring the trial to judgement without incurring liability himself for failure to serve.
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O'Brien, Elizabeth. "Post-Roman Britain to Anglo-Saxon England : the burial evidence reviewed." Thesis, University of Oxford, 1996. http://ora.ox.ac.uk/objects/uuid:e415687f-4964-4225-8bc3-23e4ab8e5e78.
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This thesis is the result of a decision to extend the approach used by me when examining Irish burial practices, to a review of the archaeological and documentary record for burial practices and associated phenomena in the transitional period from late/post-Roman Britain to Anglo-Saxon England. The study considers burial rites; the method of disposal of physical remains, the position and orientation of bodies, and burial structures and enclosures: grave-goods are only referred to when they are pertinent to a particular line of argument. My intention is to draw together the various aspects of burial of the Iron Age, Romano-British and Anglo-Saxon periods in order to look at the overall picture. Occasionally this may mean stating the obvious, but by noting and plotting distributions of various burial traits first in the Iron Age and Romano-British periods, and then comparing these traits with the Anglo-Saxon period some revealing results can be obtained. It was important to begin with the Iron Age since some minority practices current in the early Anglo-Saxon period had a continuous history from the pre-Roman period. They are of importance in demonstrating the continuities that existed alongside major changes. [continued in text ...]
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Heemskerk, Anna Dorothee. "Tuberculous meningitis : reducing the burden of disease by improving diagnosis and treatment." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:f2f9b2cf-9df0-4956-abb8-1cada367b7ad.
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Notwithstanding available diagnosis and treatment, tuberculosis (TB) is the most persistent pandemic known to modern man. Of all forms of tuberculosis, tuberculous meningitis (TBM) is the most lethal. The true burden of disease is unknown, but of the people who reach treatment facilities, approximately 30% die, despite therapy. The onset of disease is insidious and diagnosis is often only made after neurological compromise, a factor associated with increased mortality. Diagnosis is further complicated by lack of sensitivity of currently available conventional microbiological techniques. Moreover, recommended treatment regimens are derived from pulmonary TB regimens and not specifically adjusted to treat the infection in the brain, thus neglecting the differential ability of antimycobacterial drugs to cross the blood-brain barrier (BBB). Similarly, drug resistant infection is mostly detected late, because it depends on culture confirmation of this slow growing organism and optimal treatment regimens are unknown. In the context of intracranial infection, drug resistance is even more precarious, with high rates of mortality reported. This thesis addresses these pressing issues of diagnosis and treatment of TBM. The overarching aims of the studies performed in this thesis are: 1. To improve diagnosis of TBM by evaluating the performance of a novel molecular diagnostic test; Xpert MTB/RIF, 2. To improve treatment of TBM by evaluating an intensified antituberculosis treatment regimen. 3. To improve management of drug resistant TBM by exploring factors associated with drug resistance and evaluating response to intensified treatment. The Xpert MTB/RIF test was able to rapidly confirm a diagnosis of TBM with a sensitivity of 59.3% (n=108/182 (95% confidence interval(CI): 51.8-66.5)) compared to clinical diagnosis of TBM. Specificity was 99.5% (95% CI: 97.2-100). Particular advantages are the high sensitivity of the test in HIV positive patients and early detection of rifampicin resistance. Among HIV co-infected patients, sensitivity was 78.8% (n=52/66, (95% CI: 77.6-79.7)). Xpert MTB/RIF performance compared favourably with performance of commonly used classical staining techniques in most settings (1- 6 60%). This represents a significant advance in the early diagnosis of TBM and in particular of rifampicin resistance, which is considered a key drug in treatment regimens. Intensified antituberculosis treatment with higher dose rifampicin (15mg/kg) and additional levofloxacin, however, did not improve outcome in our cohort of 817 HIV infected (n=349) and uninfected (n=468) TBM patients. 113 and 114 patients died in the intensified treatment and placebo arm respectively (hazard ratio(HR), 0.94; 95% CI: 0.73 -1.22, p=0.66). Overall 9-month mortality was 28%, which is still unacceptably high. Predictors of death are HIV infection, disease severity grade on presentation and infection with multidrug resistant (MDR) mycobacteria, defined as at least resistance to rifampicin and isoniazid. The overall mycobacterial resistance rate found in this population was high; 45% of isolates showed resistance to at least one of four first line antituberculosis drugs, 27% were isoniazid resistant and MDR was detected in 5%. Patients with drug resistant infection did not have different presenting symptoms, but were more likely to have a history of previous TB treatment. Early intensified treatment did appear to be beneficial to outcome, in particular in HIV uninfected patients with isoniazid resistance (HR 0.11; 95%CI: 0.01-0.91, p=0.04). Of the 15 patients with MDR TBM, early detection of rifampicin resistance by Xpert MTB/RIF led to a successful early switch to second line therapy in four patients, who all survived up to nine months of follow up. In previous studies, prior to the availability of Xpert testing and secondline drugs, MDR TBM was uniformly lethal. Early diagnosis and treatment with effective antituberculosis drugs remains the most crucial aspect of management of this devastating condition.
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Neuvonen, Päivi Johanna. "We the burden : equal citizenship and its limits in EU law." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:13de09c4-7712-424a-8e19-48409ec0d7c7.
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The dynamic interpretation of EU citizenship as a 'fundamental status of all Member State nationals' has opened the door for more horizontal conceptions of equality in European Union law. At the same time, the meaning and purpose of equal treatment in the case of economically inactive and dependent EU citizens has remained ambiguous. The objective of this study is to clarify what normative justifications, other than to eradicate the obstacles to the internal market, can be offered for more just and equal relationships between EU citizens within the existing constitutional order of the EU. What defines EU citizenship as an equal status is how those individuals who hold this status are treated in relation to one another. The thesis discusses in detail how the rationale for discrimination analysis under Article 18 TFEU has changed in parallel with the evolution of EU citizenship. The question of how unlawful discrimination differs from legitimate differential treatment under the so-called 'real link' case law leads to a more theoretical question of what philosophical justifications underlie the EU principle of equality. The democratic theory of equality is used to support the argument that the current bias in favour of 'activity' at the expense of ‘status’ in EU equality law is rooted in a narrow and individualistic view of agency. The thesis, then, argues that recognizing the inherent connection between EU citizens' agency and their subjectivity can provide a justification for a more relational conception of equality even in the absence of a full democratic pedigree in EU law. This analysis contributes a perspective which is usually not there by examining how EU citizenship can benefit from the psycho-dynamic theories of subjectivity that underlie the feminist critique of 'citizenship as agency'.
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Howard, Dominic Peter James. "Extra-coronary arterial disease : incidence, projected future burden, risk factors and prevention." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:6ac90d2b-b919-45d4-abfd-2128efb31bc6.
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Vascular disease is the leading cause of death and disability worldwide. Incidence, risk factors, and outcome of coronary artery disease have been extensively studied, but there are fewer data on other forms of arterial disease, including carotid, aortic, visceral, and peripheral arterial disease. Although the burden of these diseases may be increasing due to the ageing population, we lack the most basic epidemiological data on which to base clinical decisions on individual patients (short and long-term prognosis); local service provision (current incidence and projected future burden); public health / screening initiatives (age and sex-specific incidence, risk factors, and outcome); and with which to assess current levels of primary prevention (pre-morbid risk factor control). Indeed, it is this lack of data, rather than a lack of treatments that is the greatest barrier to effective prevention. I have contributed to, cleaned, and analysed data from the Oxford Vascular Study, a prospective, population-based study (n=92,728) of all acute vascular events (2002-2012), and the Oxford Plaque Study, a carotid atherosclerosis biobank of over 1000 carotid plaques, in order to study these conditions. For acute aortic disease, I aimed to assess the risk factors associated with acute abdominal aortic aneurysms (AAA) and the population impact of the current UK AAA screening programme; and the incidence, risk factors, outcome, and projected future burden of acute aortic dissection. For acute peripheral arterial disease, I assessed the risk factors associated with premature onset and poor outcome, together with current levels of primary prevention. For symptomatic carotid artery disease, I studied the timing and benefits of surgical intervention in the current era; and went on to assess whether underlying carotid plaque morphology can be used to improve stroke risk stratification and help explain why ocular and cerebral stroke types have vast differences in future ipsilateral stroke risk. I found that compared with the current UK AAA screening strategy (one-off scan for men aged 65), screening of male smokers at 65 and all men at 75 would prevent nearly four-times as many deaths and three-times as many life-years lost with 21% fewer annual scans. I have also shown that incidence of acute aortic dissection is higher than previous estimates, a third of cases are out-of-hospital deaths, and uncontrolled hypertension is the most significant treatable risk factor for this condition. For acute peripheral arterial disease, the presence of multiple atherosclerotic risk factors are associated with premature onset, and severity of ischaemia, pre-morbid renal dysfunction, cardiac failure, and diabetes mellitus are predictive of future limb loss and survival. A significant proportion of acute peripheral events are AF-related in high risk patients who were not pre-morbidly anticoagulated despite having no contraindications and being at low risk of bleeding. Symptomatic carotid artery disease currently accounts for <10% of incident cerebrovascular events, and only 40% of these patients undergo surgical intervention. Due to improvements in medical therapy and on-going delays to intervention, little benefit is currently obtained from intervening in patients with <70% stenosis. Ipsilateral stroke risk is correlated with several carotid plaque features in a time-dependent manner, confirming the potential utility of plaque morphology in risk stratification. In addition, plaques from patients with cerebral events were significantly more unstable and inflammatory than from those with ocular events, helping explain differences in stroke risk between these groups. My findings advance the understanding of these conditions that form the backbone of modern vascular surgical practice, and I hope will improve prevention, clinical management, and outcome for patients with vascular disease.
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Meng, Qingfeng. "Formation and growth of fibrous mineral veins in mudrocks during burial and uplift." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:4e30518c-d118-496d-8dad-38ad4e0b18b3.
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Fibrous mineral veins are extremely important structures in mudrocks because they represent phases of geological activity that occurred after the deposition of the host rocks. They are, therefore, crucial for unravelling the geological history, especially for analyzing postdepositional tectonism, diagenesis, and associated physical and chemical conditions. This research focuses on the investigation of fibrous mineral (gypsum and calcite) veins in mudrocks, using integrated field, petrographic, and geochemical methods. The aim is to obtain a better understanding of mineral vein systems in fine-grained rocks over spatial scales ranging from reservoir to microns, regarding the timing, formation mechanism, vein growth, fluid and stress conditions, fluid-rock interaction, and their expressions in vein texture. The results reveal that fibrous mineral veins are produced during different stages of basin evolution. Fibrous calcite veins in Lower Jurassic shales in the Wessex Basin have a diagenetic growth history during early burial of the sediments. In contrast, the formation of satin spar veins in the Triassic marls of the Bristol Channel Basin is closely associated with tectonic compression during basin uplift. However, both the gypsum veins and calcite veins owe their origin to overpressure and incremental fibre growth in closed systems, with their textures exhibiting similar antitaxial characteristics. Host rock lithology, defined by mineral components, fabrics and mechanical properties, mainly controls the development of the veins. The research highlights the kinematic implications of fibre orientations for host rock deformation and the EBSD measurement of crystallographic orientations of fibres for the analysis of paleo-stress state during fibre growth. Evidence for the force of crystallization exerted by mineral fibres, which has largely been ignored in previous studies, are revealed based on field and petrographic observations. The vein systems presented in this research provide an analogue for future studies on sub-seismic scale fracture/vein characterization and prediction in mudrocks either as caprock or source rocks for hydrocarbons.
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Price, Richard P. S. "Burial practice and aspects of social structure in the late Chalcolithic of north-east Bulgaria." Thesis, University of Oxford, 1997. http://ora.ox.ac.uk/objects/uuid:e93fb806-0a9a-4250-9e42-789743ca8f5e.
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The study considers archaeological evidence for burials and other mortuary practices from the Late Chalcolithic period in north-east Bulgaria. The Late Chalcolithic is defined (circa 4500-4000 B.C.) and around 900 burials are attributed to two cultural groups within the region in this period. It is argued that previous studies of the evidence can be rejected for assuming a straightforward equivalence between burial forms and social structures. An alternative model of social organization is proposed based on the 'structuration' and 'habitus' models of Giddens and Bourdieu which emphasize the role of the individual in the reproduction of social institutions. This framework is used to examine the importance of (mortuary) rituals and the symbolic use of material culture in strategies intended to maintain or alter the distribution of power and resources. The data is examined using quantitative measures of spatial and temporal variability and statistical measures of association between variables. It is argued that two basic patterns can be discerned and which correspond to the defined cultures. The inland cultural pattern is further divided into two 'types' based on the location and forms of burials. Burial forms and grave goods are also examined qualitatively and the values attributed to artefacts, materials and the processes of burial are addressed. From this it is argued that meanings are fundamentally mediated through processes of reciprocation between kinship groups and with ancestors. Social structures based on gender and age, the settlement community and residence are proposed. 'Codes' of the use of material culture within mortuary rituals are described and evaluated through a consideration of assemblages and performance. Changes within and between cemeteries over time are used to reconstruct patterns of competition and emulation. The interpretations of social interaction in burial practices are related to other forms of evidence from the Late Chalcolithic in north-east Bulgaria and suggestions made for a new understanding of social organization in both cultures. The conclusions are placed in a wider spatial and temporal perspective and conclusions presented relating to both the data studied and the theoretical models adopted.
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Croke, Christopher Eric Johnston. "Moral hostages : refugee co-operation and burden sharing during the Indochinese refugee crisis (1975-1996)." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:d4f79ff2-a055-44b9-be8e-7194dc985a8c.
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Why were Southeast Asian states so successful in outsourcing the costs of refugee protection during the Indochinese refugee crisis (1975-1996)? By refusing to grant asylum unless other states guaranteed to resettle refugees, this dissertation argues that real and threatened mistreatment of refugees by the states of first asylum was decisive in explaining why other states agreed to resettle them. Mistreatment of Indochinese refugees not only activated strategic concerns for the political stability of first asylum countries themselves but also affective concerns for refugee welfare. Concern about what would happen to refugees if they weren't resettled helped sustain resettlement long after doubts arose as to whether those fleeing were truly refugees. And in the final resolution of the crisis, a concern for refugee welfare made the return of non-refugees extremely controversial. By looking at the private and public framing of the Indochinese refugees as a collective action problem for governments to solve, it demonstrates the salience of mistreatment in explaining burden-sharing. The study principally focuses on the actions of two major resettlement countries: the United States (the biggest in absolute terms) and Australia (the biggest in relative terms). Utilising extensive archival research, contemporary accounts and interviews with key policymakers of the period, it explores several distinct and important episodes over the duration of the outflow that reveal what motivated international assistance. This is descriptively important in adding to our knowledge of how refugees are treated as a question of international politics. The textural account of governmental motivation that is offered can also help test existing theoretical accounts of why governments cooperate to help refugees. Crucially, it shows that a humanitarian concern for refugee welfare both enabled and constrained co-operation.
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Chen, Xuan. "Eastern Han (AD 25-220) tombs in Sichuan." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:be49570b-b40c-45ac-a2e3-d17e9f3516ce.
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This thesis concerns the factors underlying the popularity of the cliff tomb, a local burial form in the Sichuan Basin in China in the Eastern Han dynasty (AD 25-220). The development of the cliff tomb was held in a complex set of connections to the development of the burial forms, and existed through links to many other contemporary burial forms, the brick chamber tomb, the stone chamber tomb, and the princely rock-cut tomb. These connections and links formed to a large extent through the incorporation of the Sichuan area into the empire which began in the fourth century BC. It was in this context, a series of factors contributed to the formation and popularity of the cliff tombs in Sichuan. The hilly topography and the soft sandstone, easy to cut, provided the natural condition for the development of the cliff tombs. The decision to make use of this natural condition was affected by many factors rooted in the social background. The inherent nature of the cliff tomb structure was fully explored, which was then followed by a series of corresponding innovations on the pictorial carvings and the burial objects. The meaning of a continuous family embedded in the cliff tomb structure was explored, as the construction of the tomb was the result of the continuous endeavours from many generations of the family, and the physical form of the cliff tomb was a metaphor for a prosperous family. Following this intention of the tomb occupants underlying the design of the cliff tomb structure, the pictorial carvings and the burial objects in the cliff tomb made adaptations to make the cliff tomb an embodiment of relations between different family members and different generations.
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Reynolds, Andrew W. M. "The burden of memories : towards a Bloomian analysis of influence in Osip Mandelstam's Voronezh notebooks." Thesis, University of Oxford, 1996. https://ora.ox.ac.uk/objects/uuid:056faaf0-dc01-4960-b87f-b7a444b9986a.
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The Voronezh poetry of Osip Mandelstam (1935-1937) is viewed by many critics as one of the most heroic of Russian literature's many confrontations between the poet and the tyrant. Recently, however, Mandelstam's image has seemed to be compromised by the existence of poems revealing a more loyalist Mandelstam, in particular an Ode written in January 1937 in praise of Stalin. Critics are divided as to whether this poem is an expression of genuine praise and loyalty, whether it was written out of pragmatic considerations, or whether it is in fact an attack, in Aesopian language, on Stalin. This thesis argues that the lack of critical concensus on this and other matters is caused in large part by certain dangers inherent in the main method (intertextual analysis) used to study Mandelstam. The thesis therefore has a dual focus: it investigates theories of intertextuality and influence as issues of central importance to current literary debates, and attempts to establish an eclectic theory which fuses elements of various approaches to intertextuality and influence; but it does so in order that the poetry of Mandelstam and other Russian poets may be better understood. The thesis provides a detailed examination of Harold Bloom's theory of influence and applies it to Mandelstam's poetry, and argues that it is possible that it may be applied fruitfully to other Russian poets. Yet Russian poetry also provides a corrective to Bloom's tendency to see poetic influence as almost exclusively a relationship between literary texts. The thesis argues that Mandelstam's poetic precursor is Pushkin, and that his sense of being Pushkin' & heir seems to place him under some sort of obligation to imitate Pushkin's life and death as well as his art an extreme case of zhlznetvorchestvo ("life-creation"). Mandelstam's most significant description of his own death as an imitation of Pushkin's is found in his "Stikhi o neizvestnom soldate" ("Verses on the Unknown Soldier"). Bloom's theory helps one realise that the "Ode to Stalin" is only a part of Mandelstam's rewriting of Pushkin's own uncertainties in his relationship with Nicholas I; one may view the "Ode to Stalin" and "Stikhi o neizvestom soldate" as a single text equivalent to Pushkin's examination in Mednyl vsadnik (The Bronze Horseman) of the conflicting claims of state and individual. Mandelstam's willingness to give the devil some of his best words is thus not incompatible with the anti-Stalin conclusions reached by his work taken as a whole.
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Liu, Yan. "Archaeological manifestations of rank and status : the wooden chamber tombs in the Mid-Yangzi Region (206 B.C. - A.D. 25)." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:67f6cce2-34d2-4b38-bf81-74bb1b6246a5.
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This thesis is centered on the roles of wooden chamber tombs in defining, negotiating and reinforcing status and identity of their owners in early imperial China. The archaeological materials under discussion are wooden chamber burials in the mid-Yangzi region, including the modern provinces of Hubei, Hunan, Sichuan and north Anhui. The first reason why I have chosen this area is because these tombs are well-preserved and provide excellent examples to examine the different material expressions of rank and status at each rank in mortuary contexts. They are complemented by some extensive contemporary texts written on bamboo strips recently discovered in the same general area. The waterlogged burial environment in the mid-Yangzi region allows organic materials, such as textiles, lacquers and bamboo manuscripts, to survive while in other regions, such as the Central Plain, they often perished. Secondly, these tombs are also of a traditional form—constructed as a wooden chamber dug into a vertical pit, and can therefore be considered in relation to earlier Zhou practices. Wooden chamber tombs started to flourish from the eleventh century and became more elaborate from the sixth to the first century B.C. From the first century onward, such a burial type still prevailed in the mid-Yangzi region, while they were replaced by horizontal tombs built with bricks or stones in other areas. Many scholars have, therefore, regarded the prevailing timber structure in the area as a cultural continuity from Zhou system. They interpret them in terms of funeral regulations, especially linking them to archaic ranks and ritual norms drawn from transmitted texts. However, many of these texts that archaeologists consult and cite were written long after the burials and sites were constructed and used. These later texts were modified and passed through many editorial hands over the centuries, and there are considerable inconsistencies between different textual sources. Therefore the second reason why I have chosen this area is because it provides data demonstrating that the text-centered assumptions with respect to archaeological material do not contribute to a better understanding of social relationships in early Han society. Thirdly, there is a strong connection with local Chu tombs. The Jianghan Plain was the heartland of the Chu state before the Qin unification. The tomb construction of the Chu state incorporates a striking preference for timber structures. The timber structure tombs grew more widespread and dominant in this area during the early Han dynasty. In using multiple burial chambers and nested coffins, the local Han elites in the mid-Yangzi region seem to have followed the Chu mortuary practice, as well as in burying a large number of lacquers and bamboo manuscripts. The abundant material evidence of Chu tombs in the area sheds light on understanding of changes in funerary beliefs, showing that the tombs were arranged to meet specific needs of tomb owners. Rather than simply seeing a wooden chamber burial as a passive reflection of written regulation, I consider it as a medium for conveying the different thoughts of its owner and their associates. The material evidence manifested the status and identities of the deceased in concrete physical form. The burial assemblages belong to carefully planned contexts, and serve to constitute idealized social relations, rather than necessarily mirroring day to day reality. As such, burial evidence not only exhibited a part of the biography of the dead, but also expressed identity and socio-political claims of the living. This thesis will show that rank is not the only and major determinant, but is accompanied or outperformed by status and identity. The period covered by this thesis is the initial stage of early imperial China. The Western Han Empire (206 B.C.--A.D. 25) is traditionally regarded as a period when a unified social, political, and ideological framework was initially established. In 202 B.C., Liu Bang (256--195 B.C.) from the former Chu state in eastern China, defeated Xiang Yu (232--202 B.C.) and set up the Western Han imperial court, with its capital in Chang'an (modern Xi'an, Shaanxi province). The Han Empire was briefly interrupted by the Xin Dynasty (A.D. 9--23), established by Wang Mang (45 B.C.--A.D.23), a Confucian official from the Liu family. This interregnum divides the Han dynasty into two periods: the Western Han (206 B.C.--A.D.9) and the Eastern Han (A.D.25--220).
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Smejkalová, Markéta. "Analýza a hodnocení rizik v pracovním prostředí skladovacích objektů." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-414173.
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The diploma thesis investigates and solves an issue of risk in a logistics company from the point of view of safety at work and personal safety in emergencies. The first part of the thesis is focused on the issue of safety at work and personal safety in emergencies in storage space in the logistics company and its theoretical solution. The following chapters of the thesis deal with identified risks and work including implemented risk analysis. Another part of the thesis consists of solutions for lowering cancelling the hazards of certain threats and danger. In the final part, summarize all the conclusions and suggest recommendations.
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Milner, James H. S. "The politics of asylum in Africa : the cases of Kenya, Tanzania and Guinea." Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:89a91ea8-d2af-4727-8f46-f57b3ac9001b.
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There is a crisis of asylum in Africa. In response to large and protracted refugee populations, declining donor assistance and a range of related security concerns, a significant number of African states have limited the asylum they offer to refugees. Some states have closed their borders to new arrivals and pursued early repatriations. Many other states have contained refugees in isolated and insecure camps. Given the scale of this crisis, the global pressures on asylum, and the disproportionate share of the global refugee burden borne by Africa, understanding the responses of African states poses an important challenge. A critical examination of the factors influencing the refugee policies of African states is, however, strikingly absent from the scholarly literature. The objective of this thesis is to address this gap by examining the responses of Kenya, Tanzania and Guinea to the arrival and prolonged presence of significant refugee populations. Drawing on field research, this thesis argues that the asylum policies of the three cases are the result of factors both related to the presence of refugees, such as burden sharing and security concerns, and unrelated to the presence of refugees, such as foreign policy priorities, democratization, economic liberalization and the sense of vulnerability experienced by many regimes in Africa. Drawing on a political history of the post-colonial African state, this thesis argues for an approach that recognizes the politics of asylum in Africa. Such an approach highlights the importance of incorporating the host state into any examination of asylum in Africa and the predominant role that broader political factors play in the formulation of asylum policies. This is not to suggest that factors such as the protracted nature of refugee populations, levels of burden sharing and security concerns are irrelevant to the study of asylum in Africa. Instead, the thesis argues that such factors are very relevant, but need to be understood in a more critical way, mindful of the political context within which asylum policies are formulated. This approach leads to important lessons not only for the study of asylum in Africa, but also for the future of the refugee protection regime in Africa.
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Xu, Weimu. "Carbon burial in continental and marine settings : lacustrine and marine records of major environmental change in deep time and their depositional and diagenetic consequences." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:8838eda2-67a4-4946-a64a-e060d71247a2.
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The Early Jurassic Toarcian Oceanic Anoxic Event (T-OAE; ~183 Ma) is recognized as possibly the most extreme oceanographic and global climatic change event of the Phanerozoic. The T-OAE was marked by massive carbon release into the ocean-atmosphere system, widespread oceanic de-oxygenation, global organic-matter burial, and a strongly perturbed global carbon cycle. Although effects of the T-OAE are extensively studied in the marine realm, the environmental and climatic response on the continents is effectively unknown. In this thesis, I identify the first lacustrine record of the T-OAE, in the Da'anzhai Member of the Sichuan Basin (China), and demonstrate that a major lake system developed contemporaneously with the T-OAE, likely due to enhanced hydrological cycling under elevated atmospheric pCO2. Increased lacustrine organic productivity from elevated fluvial nutrient supply resulted in ~460 Gt of organic carbon burial in the palaeo-Sichuan lake alone, representing a major, but hitherto overlooked, carbon sink and negative feedback in the T-OAE global carbon cycle, and likely other similar events. Algal dominated biomass, deposited under a stratified water column during lake level rise, marks the Da'anzhai Member as potential hydrocarbon source rock. Given the challenges associated with Mesozoic stratigraphic correlation, I further present the first integrated (marine) stratigraphic reference framework for the complete Toarcian Stage from the Llanbedr (Mochras Farm) Borehole (Cardigan Bay Basin, UK), which allows precise correlation between the T-OAE and coeval Karoo-volcanism. I also show that accelerated global weathering rates during the T-OAE resulted in widespread mass transport deposits at different palaeolatitudes and changes in ocean chemistry leading to pronounced marine siderite deposition. Periodic smaller-magnitude carbon cycle perturbations in the Hettangian and Sinemurian were possibly in phase with short (~100kyr) and long (~405kyr) eccentricity astronomical forcing, with the formation of organic-rich laminated black shales in the Bristol Channel Basin, similar to Mediterranean sapropels in the Pleistocene.
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Vu, Huong. "Health and economic burden of human Streptococcus suis infection in Viet Nam and the contribution of undercooked pig product consumption practices : implications for prevention and control." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:3c2d8313-130d-4399-9910-7b8cfb50855f.
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Streptococcus suis is a zoonotic bacterium capable of causing severe systemic infection in humans, including central nervous system infection (meningitis) which can lead to long-term sequelae including deafness and vestibular dysfunction. Despite a growing body of literature on the epidemiology, microbiology and molecular aspects of the disease, there has been little progress on the prevention and control of this disease in Asia. This thesis aimed to examine the long-term consequences of the disease in patients, quantify the health and economic impact, and investigate the local practice of consuming raw pig blood, one of the main risk factors for S. suis infection in Viet Nam. A systematic review and meta-analysis conducted in this thesis showed that hearing loss and vestibular dysfunction were the most common health sequelae in patients surviving S. suis infection. In a patient follow-up study at a referral hospital in Ha Noi, I found that severe hearing loss and vestibular dysfunction both occurred, and persisted over a long period in 40% of patients. Morbidity caused by these two conditions accounted for about half of the disability adjusted life years lost due to the infection. The analysis of disease impact showed that S. suis infection caused a considerable impact on the patients and their family. The direct cost of hospitalization was estimated to be 35 million VND per episode (~ 1600 USD), which was greater than the average annual per-capita income in Viet Nam. The total annual cost of the disease was 54-70 billion VND (2.5-3.3 million USD), more than 80% of which was attributed to productivity loss due to premature deaths and long-term disability. A mixed-methods community-based study, consisting of both quantitative survey and focus group discussion, showed that raw pig blood consumption was common in Viet Nam (reported in 35% of rural and 8.6% of urban participants). Many misperceptions about food safety and risk of disease transmission existed in the community; most importantly was the belief that apparently healthy or free-ranging pigs did not pose health risks to consumers. Data from this thesis can be used by public health and policy makers to prioritise and justify resource allocation and to identify options for disease prevention and control.
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Johansson, Sofia. "Osebergsgraven från person till objekt : En fallstudie om nya perspektiv på gamla tankar." Thesis, Uppsala universitet, Institutionen för arkeologi och antik historia, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413774.
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This paper is a case study of the Viking Age ship burial from Oseberg, Norway. The aim of this paper is to use the concept of persona developed within rhetoric’s, and to investigate if it is possible to apply it on archaeological materials such as the Oseberg burial. The concept of persona as developed by Birgitte Mral is to identify strategies used by individuals to change their personality in order to enable themselves as a part of the public sphere. It is argued here that applying persona is a complement method to use in archeological research with a focus on gender. Although gender theory has previously been implemented on the Oseberg find, the history of its interpretations is still deeply influenced by the original interpretations put forward after the excavation in 1904. Therefore, a discussion based on analogies is conducted to evaluate the use of persona in gender archaeology in relation to other archeological interpretations of the Oseberg burial. The case study has introduced persona in an archeological context and used persona as a method and theoretical framework to gain new perspectives on how archaeologists can study the people in a grave rather than larger cultural events. The analysis based on analogies showed how persona can be used as a reflective tool as well as a theoretical framework.
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Uduwawala, Disala. "A comprehensive study of resistor-loaded planar dipole antennas for ground penetrating radar applications." Doctoral thesis, Stockholm : Division of Electromagnetic Engineering, School of Electric Engineering, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4110.
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Hartley, Helenann Macleod. "We worked night and day that we might not burden any of you (1 Thessalonians 2:9) : aspects of the portrayal of work in the Letters of Paul, late Second Temple Judaism, the Græco-Roman world and early Christianity." Thesis, University of Oxford, 2005. http://ora.ox.ac.uk/objects/uuid:e650a043-eb1b-4f13-88a3-b3775bab0355.
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In recent years, a prolific amount of books and articles on Paul have sought to bring Paul's life and theology into new light. This dissertation is an investigation into an aspect of Paul's life and thought which has remained little discussed in secondary literature, even when as of late, the social world of Paul has been in more focus — that of Paul's portrayal of manual work, and Ins use of the imagery of the workplace (ideas of toil, labour, weakness, slavery, economics, and so on). The thesis contributes to our understanding of what may have affected the portrayal of work in Paul's thought by surveying all the available evidence, and secondly, it concludes by way of providing a balance to the studies of Hock and others, that Paul's portrayal of work was derived from his Jewish heritage as well as his Graeco-Roman context. The first chapter introduces the subject, surveys previous research to demonstrate the need for the present study, and sets out the broader context of the literature to be examined. Chapter two considers the Jewish evidence. Two ways of looking at work are identified. Firstly, the portrayal of God as worker is examined and secondly, the portrayal of human work is discussed. These themes shape chapter three which discusses the Graeco-Roman evidence, and Chapter four which examines the non-Pauline Christian material. Chapter five considers the portrayal of work in the Pauline letters, cross-referencing with the previous chapters where relevant. The final chapter summarises the conclusions that are drawn from the evidence and outlines their implications for current scholarship in Paul.
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Nounouh, Soufiane. "Protocoles de mesure et de calibrage de champs électromagnétiques en vue de l'imagerie par diffraction d'objets faiblement enfouis." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4750/document.
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Cette thèse est consacrée à la mise en place d'un système hyperfréquence dédié à l'imagerie du proche sous-sol. L'analyse de l'onde mesurée après interaction de l'onde incidente avec le milieu permet de remonter aux propriétés électromagnétiques de la structure illuminée. Ici, nous choisissons d'utiliser une seule fréquence en s'appuyant sur une configuration multistatique pour garantir une meilleure diversité de l'information.L'imagerie quantitative exige un calibrage minutieux des données mesurées après correction des erreurs expérimentales. Un calibrage a été donc proposé, basé sur la mesure du diagramme de rayonnement de chaque antenne. Celles-ci sont modélisées quantitativement en champ proche grâce à une combinaison de fils sources adéquatement optimisée. Ce calibrage, rapide et simple, ne nécessite pas d'objets de calibrage supplémentaires. Il a été d'abord testé dans le cas de la diffraction par des objets 2D en espace libre, puis dans le cas d'objets faiblement enfouis. Les champs calibrés servent de données d'entrée à des algorithmes d'inversion. En terme de localisation, les résultats obtenus sont très satisfaisants. Quant à la caractérisation, la configuration stratifiée apparaît bien moins propice que la configuration en espace libre, de part la faible quantité d'information disponible. Des changements ont été apportés à la configuration (différentes antennes avec ou sans orientation) dans l'optique d'améliorer le rapport signal à bruit. Bien que les reconstructions des permittivité soient encore perfectibles, les premiers résultats sont intéressants d'autant plus que les algorithmes n'exploitent aucune information a-priori sur la cibleThis thesis is devoted to the development of a microwave system dedicated to subsurface imaging applications. The analysis of the measured wave after the interaction with the medium allows to retrieve the electromagnetic properties of the probed structure. Here, we choose a single frequency operating mode combined with a multistatic configuration in order to improve the information diversity.Quantitative imaging requires a high-precision calibration of the measured data even after a careful correction of experimental errors. Thus, a calibration method is proposed, exploiting the measurement in free-space of the radiation pattern of each antenna. These patterns are quantitatively modeled thanks to an optimized linear combination of elementary sources positioned on the antenna's aperture. This simple and efficient calibration avoids additional measurements with calibration objects. This method provides successful results in a 2D free space scattering problem, as well as in the shallowly buried targets case.The calibrated data serve as inputs to inversion algorithms. As localization is concerned, very satisfactory detection results are obtained. Regarding the characterization aspects, the results indicate that the stratified configuration is less suitable than the free space configuration, due to its lack of spatial information. In order to improve the signal-to-noise ratio, some amendments are made to the experimental configuration (different antennas with or without orientation). Although the permittivity reconstructions are perfectible, the first results are promising especially since no a-priori on the targets has been inserted in the inversion algorithm so far
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Jones, Emily. "Constructing a conservative : the reception of Edmund Burke in British politics and culture, c. 1830-1914." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:06d5fb72-9272-4255-a2ae-51c31d89063b.
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Between 1830 and 1914 in Britain a dramatic modification of the reputation of Edmund Burke (1730-97) occurred. Burke, an Irishman and Whig politician, is now most commonly known as the 'founder of modern conservatism' – an intellectual tradition which is also deeply connected to the identity of the British Conservative party. Indeed, the idea of 'Burkean conservatism’ – a political philosophy which upholds ‘the authority of tradition', the organic, historic conception of society, and the necessity of order, religion, and property – has been incredibly influential both in international academic analysis and in the wider political world. This is an intellectual construct of high significance, but its origins have not hitherto been understood: insofar as it has been considered at all, it has been typically seen as the work of Cold War American conservatives. In contrast, this thesis demonstrates that the transformation of Burke into the 'founder of conservatism' was in fact part of wider developments in British political, intellectual, and cultural history in the nineteenth and early twentieth centuries. Drawing from a wide range of sources, including political texts, parliamentary speeches, histories, biographies, and educational curricula, this thesis provides a properly contextual history of political thought. It shows how and why Burke's reputation was transformed over a formative period of British history. In doing so, it bridges the significant gap between the history of political thought as conventionally understood and the history of the making of political traditions. The result is to show that, by 1914, Burke had been firmly established as a 'conservative' political philosopher and was admired and utilised by political Conservatives in Britain who identified themselves as his intellectual heirs. This was one essential component of a conscious re-working of 'C/conservatism', especially from the mid-1880s, which is still at work today.
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Baker, Jack. "Analyse des objets de parure pour explorer la diversité culturelle et sociale au cours du Gravettien en Europe." Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0277.
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Le Gravettien (34-24 ka) est largement considéré comme le dernier technocomplexe paneuropéen avant la fragmentation régionale de la population à la suite du dernier maxima glaciaire. Il a été démontré que les ornements personnels sont de puissants indicateurs du statut social et de l'appartenance culturelle. Jusqu'à présent, les ornements personnels omniprésents dans les sites d'occupation et de sépulture caractérisant le Gravettien n'ont pas encore fait l'objet d'une étude approfondie. L'objectif principal de la thèse était de documenter la variabilité des associations de types de perles et d'identifier les mécanismes à l'origine de cette diversité à l'échelle régionale et européenne au cours du Gravettien. La réalisation de cet objectif a ouvert la voie au second objectif : l'étude de la géographie culturelle des communautés gravettiennes. Dans un premier temps, nous proposons une analyse approfondie des nombreuses parures provenant d'un site funéraire clé du Gravettien, Cro-Magnon (Dordogne, France). Ensuite, nous avons créé une base de données géoréférencée représentative des parures du Gravettien, comprenant 164 types provenant de plus de 130 sites à travers l'Europe, et nous l'avons analysée à l'aide de méthodes statistiques multivariées et spatiales, telles que l'analyse des coordonnées principales (PCoA), le Neighbour-joining, le Neighbour-net, la sériation et les corrélations et corrélogrammes de Mantel. Nous avons ensuite comparé et mis en contraste les parures du Gravettien avec celles de l'Aurignacien précédent en utilisant des analyses similaires afin d'étudier s'il existait une continuité entre ces deux technocomplexes. L'analyse des parures trouvées à Cro-Magnon a révélé l'existence de vastes réseaux d'échange à travers le continent. Malgré des similitudes avec les parures d'autres groupes voisins de Dordogne, les parures de Cro-Magnon présentent un caractère distinctif, c'est-à-dire peu, plutôt que beaucoup, de pendentifs en ivoire décorés et beaucoup, plutôt que peu, d'ornements en coquillages, ce qui souligne le désir de ce peuple d'affirmer son identité unique dans un contexte symbolique plus large. Le recalibrage de la seule date radiocarbone disponible pour ce site suggère qu'une campagne de datation plus étendue est nécessaire pour attribuer chronologiquement ce site emblématique avec précision. L'analyse de la base de données du Gravettien européenne révèle que ce technocomplexe était divisé en neuf groupes qui portaient des associations de types de perles différentes, organisées d'ouest en est. Alors que les groupes gravettiens de l'est de l'Europe 10 portaient des parures principalement en ivoire, en pierre et en dents de mammifères carnivores, les groupes de l'ouest avaient tendance à porter des perles fabriquées à partir de coquillages marins et de dents de mammifères herbivores. Il a été démontré que les différences observées dans les associations de types de perles n'étaient pas uniquement dues à l'isolement par la distance. Nous en avons conclu qu'un sentiment d'appartenance culturelle dictait les types de parures portés par les différents groupes de Gravettiens. Les sites d'inhumation et d'occupation se caractérisent par des schémas distincts d'associations de parures. La différence observée entre les groupes d'inhumation était plus importante que la différence entre les groupes d'occupation. La comparaison des parures du Gravettien et de l'Aurignacien a révélé des similitudes frappantes entre les deux technocomplexes en termes de choix de parures. Le Gravettien se caractérise par des régions d'associations de parures similaires, dont la surface est plus de dix fois supérieure à celle de l'Aurignacien et qui sont plus interconnectées que ces dernières. Les types de parures entièrement sculptés dans des matériaux osseux et lithiques marquent mieux le fossé culturel entre ces deux technocomplexes que ceux produits à partir de formes naturelles minimalement modifiéesThe Gravettian (34–24 ka) is widely considered as the final Pan-European technocomplex before the regional fragmentation of the population following the Last Glacial Maxima. Personal ornaments have been shown to be powerful indicators of social status and cultural affiliation. Hitherto, the ubiquitous personal ornaments found in occupation and burial sites characterising the Gravettian have yet to be the subject of a comprehensive study. The primary aim of the PhD was to document the variability in bead-type associations and identify the mechanisms driving this diversity at both regional and European scales during the Gravettian period. Achieving this paved the way for the second aim: investigating the cultural geography of Gravettian communities. We first provide an in-depth analysis of the numerous personal ornaments coming from a key Gravettian funerary site, Cro-Magnon (Dordogne, France). Subsequently, we created a representative georeferenced bead database of Gravettian personal ornaments encompassing 164 types coming from over 130 sites across Europe and analyse it using multivariate and spatial statistical methods, such as principal coordinates analysis (PCoA), Neighbour-joining, Neighbour-net, seriation and Mantel correlations and correlograms. We then proceeded to compare and contrast the Gravettian personal ornaments with those coming from the preceding Aurignacian using similar analyses in addition to k-means clustering, perMANOVA and Archaeological Similarity Networks to investigate whether continuity existed between these two technocomplexes. Analysis of the personal ornaments found at Cro-Magnon revealed the existence of extensive exchange networks across the continent. Despite sharing similarities with ornaments from other nearby groups in Dordogne, the Cro-Magnon ornaments exhibit a distinctiveness, i.e., a small, rather than large, number of decorated ivory pendants and a large, rather than small, number of shell ornaments, that highlights this people’s desire to assert their unique identity within a broader symbolic context. The recalibration of the only available radiocarbon date for this site suggests that a more extensive dating campaign is necessary to chronologically attribute this iconic site accurately. The analysis of the European-scale Gravettian database reveals that this technocomplex was split into nine groups who wore different bead-type associations which were organized in an east-west cline across Europe. Whereas Gravettian groups from the east of Europe wore personal ornaments predominantly fashioned from ivory, stone and mammal carnivore teeth, groups from the west tended to wear beads made from 8 marine shells and mammal herbivore teeth. The observed differences in bead-type associations were shown to not be solely due to Isolation-by-Distance. From this we concluded that a sense of cultural belonging dictated the personal ornament types different groups of Gravettian people wore. Burial and occupation sites were characterised by distinct patterns of personal ornament associations. The observed difference between burial groups was higher than the difference between occupation groups. The comparison of the Gravettian and Aurignacian databases unveiled stark similarities in terms of personal ornament choices between the two technocomplexes. The Gravettian was characterised by regions of similar personal ornament associations which had over ten times the surface area and which were more interconnected than those of the Aurignacian. Personal ornaments types fully carved out of osseous and lithic material better marked the cultural divide between these two technocomplexes than those produced from minimally modified natural forms
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Jiang, Qichen. "Tang sancai." Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:de5211ba-7110-4e58-ba7a-ec91c3f94d32.
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This thesis studies Tang sancai, a multi-coloured lead-glaze ceramic decorated ware which emerged in the Tang dynasty (AD 618 - AD 907), attaining mass production in the middle of the Tang era and declining towards its end. It examines the functions of sancai in its different aspects, namely as burial objects, as containers for ritual offerings and as architectural material. I argue that Tang sancai ware as burial objects were employed exclusively by the Tang imperial and elite families. The approach to my argument is made, in a first stage, through the observation of the physical locations of tombs that contained Tang sancai wares to demonstrate that these tombs belonged to the Tang imperial and elite family members. In a further step, I bring up two Tang decrees which laid down regulations for burials, to indicate that there was a strict hierarchical system for the allocation and utilization of burial land. These two Tang texts enable us to establish that the tombs located around the area of the imperial tombs belonged to the Tang officials and elite, and therefore not to ordinary people. In addition, the study I undertake of the structure of the tombs, with layout and organization mirroring palatial environments, reinforces my argument to that end. Lastly, I look at the cost of production of Tang sancai showing that it was higher than that of unglazed ceramics and that, consequently, sancai wares were, from an economical point of view, inaccessible to the common people. This thesis also reflects on the agency of Tang sancai, considering its aesthetic qualities and its suitability in the functions for which it served, as a force in engaging the viewers. The lasting debate on whether Tang sancai utensil-shaped wares were used for everyday eating and drinking is dealt with in this thesis by carefully examining the locations of the shards that were excavated at the sites of imperial palaces. My research enables to point out that this data is not sufficient to ascertain that this type of Tang sancai was used as daily wares. On the contrary, on the grounds that these locations were the places where ritual performances took place, I argue that sancai utensil wares were used as presentation containers for ritual performances. In the absence of records in Tang texts which could have informed about the relationship between Tang sancai and religious practice, I borrow an evidence from Japan, in the form of the hand-brush writing on a couple of Nara sancai dishes, which were copies of Tang sancai made in Japan during the time of Tang, mentioning that these vessels were specifically for use for ritual ceremonies. Furthermore, on the basis of analyses made on lead-glazed ware, some scholars assert that such ware is poisonous and could not have been used to contain food or drink, as much as no evidence exists to show that ancient Chinese had used lead-glazed wares for that purpose. This leads to the clarification that Tang sancai utensil-shaped wares were not produced for everyday use, their purpose having actually been to serve as vessels for offerings in rituals. I further observe that this connection between sancai and ritual-themed objects, initiated by the Tang, has in fact pervaded through the succeeding dynasties affirming its role in religious ceremonials. Finally, this thesis also looks at Tang sancai as an architectural material to show that it was skillfully used in decorating buildings, not only as tiles and tile-ends, but also as large-sized roof ornaments. The research reveals, in the process, the possible dates when sancai architectural material started to be used popularly during the Tang era.
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Adomaitienė, Rita. "Gyventojų pajamų mokesčio analizė ir tobulinimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050525_100619-67099.
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Final master work consists of 62 pages, 9 figures, 11 tables, 40 sources of literature, lithuanian language. Key words: tax, taxation, principles, the burden of taxation, tax rate, tax shield, tax-free income, tax object, tax subject. The object of researching is income tax. The subject of researching is analysis and improvement of income tax. The aim of the work is to explore the essence, necessity and functions, to analyse taxable principles and purposes of the income tax in order to make suggestions how to improve and perfect them. The purpose of the work: 1. to survey tax doctrine and show why tax is needed; 2. to do the analysis of income tax and the burden of taxation; 3. to make suggestions how to improve income tax. The methods of research: in combining methods of analysis (monographic, statistic, logical, horizontal and vertical analysis ) and means (comparicon, graphical) to present suggestions how to improve the Tax of Personal Income.
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Ren, Kai. "Physics-Based Near-Field Microwave Imaging Algorithms for Dense Layered Media." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1511273574098455.
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Noteboom, Emilie Jeannette. "Critical analysis of Guillaume Groen van Prinsterer's Christian-historical principle, with a comparative critical analysis of his argument of 'history' with that of Edmund Burke's as used in their critique of the French Revolution." Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:6233d0bf-9fd2-4c4a-ad1c-9becb5cd514c.
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This thesis provides an analytical interpretation of the critique Dutch nineteenth-century statesman-cum-historian Guillaume Groen van Prinsterer (1801-1876) articulated of French revolutionary ideology. It achieves an original reading of Groen's thought as Protestant right-order theory. This reading achieves a clarification of the functions that Scripture, 'nature', and 'history' have in his thought, and connects his thinking to that of a small group of contemporary British-based political theologians, notably Oliver and Joan Lockwood O'Donovan, and their minority view on the ontological grounding of justice. Our comparison of Groen's argument of 'history' with that of Edmund Burke achieves original critical leverage on their concepts of 'history', and draws out that Burke's critique of the Revolution purposes to re-affirm English common law, while Groen's is an apologia for Christianity.
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Gabriel, Schenk. "A type of king : the figure of Arthur in mid-nineteenth to mid-twentieth century literature." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:6c284cea-e72c-49b0-ba87-29cf7b960ba9.
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This thesis analyses the figure of Arthur, in a period spanning the mid-nineteenth to mid-twentieth centuries, when that figure became increasingly protean and multifaceted, and the audience for the Arthurian legend grew in both size and variety. It argues that many authors wrote through Arthur, as well as about Arthur, using the figure to understand and test their own ideas about ideals (e.g. of manliness, kingship, or heroism) as well as problems (such as war, despotism, or ungodliness). This thesis analyses Arthur by considering him as a 'type', using a definition of the term that highlights a paradox: a type, in a scientific sense, is both perfect (an exemplary model) and normal (common enough to be representative). When applied to Arthur, it means that he is both a perfect, or near perfect, example, but is also to some extent a 'normal' human being. Different authors analysed in this thesis emphasise different aspects of the figure, according to whether they focus on Arthur's perfection or his normality. Other meanings of the word 'type' are also applied when relevant: the idea is not to force all versions of Arthur into a single or definitive category, but to retain the complexity of how Arthur is characterised and written about in texts. The ultimate aim of this thesis is to put the figure of Arthur into critical focus, and explain why he has been returned to so often in history.
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Terroux-Sfar, Florence. "Les règles de preuve et les évolutions du droit du travail." Thesis, Paris 10, 2012. http://www.theses.fr/2012PA100037.
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Le droit du travail a connu au cours de ces trente dernières années des évolutions remarquables avec, d’une part, l’apparition de nouvelles technologies de l’information et de la communication au sein des entreprises et, d’autre part, l’émergence de l’exigence de justification. Alors que les employeurs sont désormais tenus d’énoncer leurs raisons d’agir et que les salariés travaillent sur des postes informatisés, se pose la question de savoir dans quelle mesure ces nouvelles caractéristiques du monde du travail ont modifié les règles de preuve applicables en la matière. Si la charge de la preuve ne paraît pas avoir été affectée par ces différentes évolutions, il en va différemment de l’objet de la preuve. En effet, l’apparition des toutes dernières technologies de l’information et de la communication participe, au-delà des apparences, à un déplacement de l’objet de la preuve, les salariés ayant désormais accès à de nouveaux éléments de preuve susceptibles d’emporter la conviction des juges. Par ailleurs, l’exigence de justification invite les juges à contrôler plus avant la décision des employeurs. Ces derniers doivent en effet désormais expliciter leurs raisons d’agir. Cela signifie concrètement qu’ils ne peuvent se contenter d’invoquer des faits objectifs, ils doivent encore convaincre les juges de la justesse de leurs décisions en détaillant les ressorts de ces dernières. Ainsi, alors que la doctrine classique avait pour habitude d’affirmer que l’offre de preuve attendue des plaideurs porte sur des faits pertinents, contestés et contestables, l’exigence de justification nous amène à ajouter des faits « contextués », c’est-à-dire des faits articulés au sein d’un discours cohérent et si nous avions pu penser dans un premier temps que l’émergence de l’exigence de justification se traduise par une part croissante de subjectivité dans les décisions de justice, force est de reconnaître au contraire que le contrôle des juges s’est renforcéThe labor law knew during these last thirty years remarkable evolutions with the appearance of new information technologies and communication in the companies and, the creation of “justification’s requirement”. In the mean time employers are now obliged to detail the motivations of their actions and the employees are working more and more on informatics work station. It’s important to understand how these new characteristics have modified the application of the rules of the proof. If the proof’s burden seems to not have been affected by these evolutions, it is not the same about the proof’s object. Indeed, beyond the appearances, the new information and communication technologies lead to a modification of the proof object by giving to the employees the access of new elements of proof susceptible to influence the judge’s conviction. Besides, the “justification’s requirement” invites the judges to better control the employer’s decision. They have now the obligation to clarify their reasons for action. Concretely it means that, to support their claims, they can’t just argue objective facts to convince the judge but they have to justify the logic of their decisions. So, while the classic doctrine had for practice to expect relevant, controversial and questionable facts as proof objects, the “justification’s requirement” brings us to add “sensible facts" (facts articulated within a coherent speech). If at the first time, we could think that the “justification’s requirement” emergence will lead to subjective decision, we are obliged to admit the reinforcement of the judge control
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Draycott, Catherine M. "Images and identities in the funerary art of Western Anatolia, 600-450 BC : Phrygia, Hellespontine Phrygia, Lydia." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:6654d163-aaca-4aca-a695-4ef8bec2d6dd.
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The dissertation analyses the reliefs and paintings on thirty-one different tombs in Western Anatolia erected between 600 and 450 BC, in order to illuminate the ways in which non-Greek elites were identified on their memorials. The tombs from three areas are treated: Phrygia, Hellespontine Phrygia and Lydia, where the primary language groups were Phrygian, Mysian and Lydian. There is little literary evidence for these regions, and what there is tends to focus on political developments. Descriptions of people and society are few, and tend to represent them from an outside perspective, grouping them according to cultural characteristics which differentiate them from Greeks. It is clear, however, that the regions were important, prosperous places, controlled by illustrious grandees and land marked with a relatively high proportion of monumental tombs. Of these monumental tombs, there is a relatively high number decorated with striking and articulate images. There is much to be gained from examining the images on these tombs, as ‘indigenous’ sources for how elite Western Anatolians described themselves. Previous approaches to the tombs and their images have tended to look at them individually or in smaller groups, and to concentrate on the transmission and reception of Persian and Greek culture in the Achaemenid provinces. This dissertation contributes a broader comparative study of the decorated tombs, focussing on the kinds of statuses the images represent and the cultural forms these took. By comparing the various methods of self-representation, it clarifies patterns of identities in Western Anatolia and their relationship to historical circumstances. The dissertation is divided into five chapters. An introduction outlines the scope and sample, the historical background, previous studies of the monuments, the definition of ‘identity’ and the methods of analysis adopted here. Three case study chapters present the regions and the decorated monuments within them. A concluding chapter synthesises three aspects: social identities (roles and spheres of life represented); geographic and chronological patterns; and cultural affiliations and orientations. The dissertation concludes that a tension between Persian identities and local traditions is evident in some of the tomb images, which relates to the political upheavals in Western Anatolia and the Aegean at the time of the Persian Wars.
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Kellett, Lucy. ""Enough! or too much" : forms of textual excess in Blake, Wordsworth, Coleridge and De Quincey." Thesis, University of Oxford, 2016. http://ora.ox.ac.uk/objects/uuid:641b0fe2-3b07-46cf-94b6-7d27a2878686.
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My thesis explores the potential and the peril of Romantic literature's increasingly complex forms through a close comparative study of the works of William Blake, William Wordsworth, Samuel Taylor Coleridge and Thomas De Quincey. These writers exemplify the Romantic predicament of how to make vision manifest – how to communicate one's imaginative and intellectual expansiveness without diminishing it. They sought different strategies for increasing the capacity of literary form, ostensibly in the hope of communicating more: clarifying meaning, increasing accessibility and intensifying original experience. But textual expansion – materially, stylistically and intellectually – often threatens more opportunities for confused and partial meanings to proliferate, overwhelming the reader by dividing texts and undermining attempts at coherent thought. Expansion thus becomes excess, with all its worrying associations of superfluity. To further complicate matters, Burke's influential tenet of the Sublime makes a virtue out of excess and obscurity, raising the problematic spectre of deliberately confused/confusing texts that embody an aesthetic of incomprehension. I explore these paradoxes through four types of 'textual excess' demonstrated by the writers under discussion: firstly, the tension between poetry and prose adjuncts, such as prefaces and notes, in Wordsworth and Coleridge; secondly, De Quincey's indulgent verbosity and struggle to control the freeing shapelessness of prose; thirdly, Wordsworth's and De Quincey's parallel experiences of revision as both uncontrollably diffusive and statically concentrated; and lastly, Blake's more deliberate, systematic attempt to enact a literary Sublime in which the reader is forced out of passivity by the competing demands of verbal and visual media. All are motivated and thwarted in varying degrees by their anxious preoccupation with saying "Enough", and the difficulty of determining when this becomes “Too much”. These authorial dilemmas also incorporate larger concerns with man's (over)ambition at a time of rapid and unprecedented economic, social and intellectual acceleration from the Enlightenment to industrialism. The fear that the concept and process of 'progress', or 'improvement', marks deficiency rather than fulfilment haunts Romantic writers.
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Geise, Susanne Seybold. "From Ambiguity to Perspicuity: Applying Burke's Pentad as a Means of Preserving and Expanding the Discourse Community of Blacksmithing History in Hancock County." University of Findlay / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=findlay1525801452672734.
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