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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Wave breaking on fixed impermeable and mobile permeable beaches

Canning, Paul John January 2002 (has links)
No description available.
2

Nearshore waves and longshore shingle transport

Chadwick, Andrew John January 1990 (has links)
No description available.
3

Petrology of the Shingle Creek porphyry

Bostock, Hewitt Hamilton January 1956 (has links)
A brief description of the geology of the Shingle Creek area southwest of Penticton B.C. together with a more detailed report on the mineralogy and petrology of the Shingle Creek Intrusion (granite porphyry) are given. The presence of flows and tuffs showing similar mineralogical features to the Shingle Creek: Intrusion suggest that this intrusion was shallow rather than deep-seated. Sanidine phenocrysts showing oscillatory zoning are described with a range in composition of from 40 to 70 percent orthoclase (based on a comparison of optical properties with those determined by Tuttle 1952). The zones often occur in pairs showing a gradation from an albite-rich inner zone to an orthoclase-rich outer gone, It is tentatively suggested here that pressure changes in the magma, by altering the liquidus - solidus relations, sight provide this reversed- zoning. Plagioclase phenocrysts from the intrusion show transitional to high temperature optics when compared with the results of Bowen and Tuttle 1950. Beta quartz phenocrysts showing rounded outlines and development of late halos are described, from evidence given it is suggested that these features are due to resorption of quartz in a magma chamber prior to intrusion, followed by late growth after intrusion and daring crystallization of the porphyry matrix, Petrographlc study of the largest dyke associated with the porphyritic intrusion has suggested that this dyke may have been intruded in several stages. / Arts, Faculty of / Geography, Department of / Graduate
4

Reflections on the roots of the shingle style and the continuity of tradition in the new shingle style

Panagore, Cynthia Marie 08 1900 (has links)
No description available.
5

Process-based modelling of storm impacts on gravel coasts

McCall, Robert Timothy January 2015 (has links)
Gravel beaches and barriers occur on many high-latitude, wave-dominated coasts across the world. Due to their natural ability to dissipate large amounts of wave energy, gravel coasts are widely regarded as an effective and sustainable form of coastal defence. However, during extreme events waves may overtop, overwash, and even lower, the crest of the gravel beach, flooding the hinterland. In the evaluation of the safety of gravel coasts against flooding, coastal managers currently rely on models that have been shown in previous studies to be inaccurate. The research in this thesis attempts to improve the current predictive capacity of gravel beach storm response by developing a new process-based model to simulate storm impacts on gravel coasts. The numerical model developed in this thesis, called XBeach-G, is a morphodynamic, depth-averaged, cross-shore profile model, based on the XBeach model for sandy coasts (Roelvink et al., 2009). The model simulates the morphological response of gravel beaches and barriers to storms by solving: (1) intra-wave flow and surface elevation variations using a non-hydrostatic extension of the non-linear shallow water equations; (2) groundwater processes, including infiltration and exfiltration, using a Darcy-Forchheimer-type model; and (3) bed load transport of gravel using a modification of the Van Rijn (2007a) bed load transport equation to include flow acceleration effects, which are shown to be significant on coarse-grained beaches. The model is extensively validated for hydrodynamics, groundwater dynamics and morphodynamics using detailed data collected in physical model experiments, as well as data collected in the field on four natural gravel beaches in the UK and one in France. Validation results show that the model has high quantitative skill in simulating observed hydrodynamics on gravel beaches across a wide range of forcing conditions, in particular with regard to wave transformation, wave run-up and wave overtopping. Spatial and temporal variations in groundwater head are shown to be well represented in the model through comparison to data recorded in a physical model experiment. Validation of the morphodynamic component of XBeach-G shows that the model has high model skill (median BSS 0.75) in simulating storm impacts on five gravel beaches during ten storm events, with observed morphodynamic response ranging from berm-building to barrier rollover. The model is used to investigate hydrodynamic processes on gravel beaches during storms, where it is found that incident-band variance is elemental in the generation of wave run-up on gravel beaches. Furthermore, simulations of wave run-up during high-energy wave events show a distinct disparity between run-up predicted by empirical relations based on the Iribarren parameter and wave steepness, and run-up predicted by XBeach-G, where predictions by the empirical relations substantially underestimate observed wave run-up. Groundwater processes are shown, by means of sensitivity simulations, to strongly affect the morphodynamic response of gravel beaches and barriers to storms. The research in this thesis supports the hypothesis that infiltration in the swash is a key driver for the berm-building response of gravel beaches and helps to reduce erosion of the upper beach during storms. Through model simulations on a schematic gravel barrier it is shown that groundwater processes effectively increases the capacity of gravel barriers to withstand storms with 1-3 m higher surge levels than if groundwater processes did not occur. Reducing the width of a barrier leads to a lowering of this capacity, thereby reducing the resilience of the barrier to extreme storm events. Despite its strong influence on gravel beach morphodynamics, it is found that infiltration plays a relatively small role on wave run-up levels on most natural gravel beaches (median R 2% run-up level reduction of 8%). Application of the model in validation simulations and sensitivity simulations in this thesis, as well as in storm hindcast simulations discussed by McCall et al. (2013) shows the value of using the process-based XBeach-G model in coastal flooding analysis over the use of empirical tools. While no model can be considered entirely accurate, application of XBeach-G in all hindcast overwash simulations has lead to reasonable estimates of overtopping discharge and of morphological change, which is a significant improvement over the frequently substantial errors of the empirical tool designed for this purpose.
6

Manöverkrigföring i amfibieoperationer : En fallstudie av operation Shingle och operation Chromite

Bergh, Andreas January 2024 (has links)
The amphibious operation, one of the most complex operations one can undertake, compriseall services and is regarded as the precursor of today’s joint operations. Though questioned, leading theoretics on the subject are convinced that the amphibious operation´s unique ability to exploit mobility and provide access will remain relevant in the foreseeable future. This thesis examine dominant theories on amphibious assaults and extracts the fundamental principles upon which they rely. These are then tested on two cases, Operation Shingle and Operation Chromite. Robert Leonhard´s Maneuver theory is presented as an alternative theory. The thesis concludes that maneuver theory can explain success where amphibious theory fails. Moreover, Surprise and exploitation thereof seem to be the most valuable principlesfrom the amphibious theoretics. Those two relate closely to maneuver theory´s preemption, dislocation and disruption
7

Statistical Methods for Dating Collections of Historical Documents

Tilahun, Gelila 31 August 2011 (has links)
The problem in this thesis was originally motivated by problems presented with documents of Early England Data Set (DEEDS). The central problem with these medieval documents is the lack of methods to assign accurate dates to those documents which bear no date. With the problems of the DEEDS documents in mind, we present two methods to impute missing features of texts. In the first method, we suggest a new class of metrics for measuring distances between texts. We then show how to combine the distances between the texts using statistical smoothing. This method can be adapted to settings where the features of the texts are ordered or unordered categoricals (as in the case of, for example, authorship assignment problems). In the second method, we estimate the probability of occurrences of words in texts using nonparametric regression techniques of local polynomial fitting with kernel weight to generalized linear models. We combine the estimated probability of occurrences of words of a text to estimate the probability of occurrence of a text as a function of its feature -- the feature in this case being the date in which the text is written. The application and results of our methods to the DEEDS documents are presented.
8

Statistical Methods for Dating Collections of Historical Documents

Tilahun, Gelila 31 August 2011 (has links)
The problem in this thesis was originally motivated by problems presented with documents of Early England Data Set (DEEDS). The central problem with these medieval documents is the lack of methods to assign accurate dates to those documents which bear no date. With the problems of the DEEDS documents in mind, we present two methods to impute missing features of texts. In the first method, we suggest a new class of metrics for measuring distances between texts. We then show how to combine the distances between the texts using statistical smoothing. This method can be adapted to settings where the features of the texts are ordered or unordered categoricals (as in the case of, for example, authorship assignment problems). In the second method, we estimate the probability of occurrences of words in texts using nonparametric regression techniques of local polynomial fitting with kernel weight to generalized linear models. We combine the estimated probability of occurrences of words of a text to estimate the probability of occurrence of a text as a function of its feature -- the feature in this case being the date in which the text is written. The application and results of our methods to the DEEDS documents are presented.
9

"The War Comes First": Lt. Col. Francis Carroll Grevemberg and the Development of a World War II Antiaircraft Artillery Officer

Janous, Robert 14 May 2010 (has links)
This thesis deals with the life and career and intimate life of Francis Carroll Grevemberg, an antiaircraft World War II officer from New Orleans, Louisiana. Grevemberg joined the Louisiana National Guard in 1932 and began his military career in the midst of the Great Depression. In the reorganization of the U.S. Army before World War II, the War Department transformed Grevemberg's cavalry regiment into a coastal artillery battalion with antiaircraft capability. During World War II, Grevemberg saw continuous action in the North Africa, Italy and Southern France. He regularly wrote letters from battlefields to his wife Dorothy. These letters provide a important window into a young officer's feelings, thoughts and affection in the unfolding of World War II. They are documents of a soldier's emotional release during times of crises. Lt. Col. Grevemberg is a rare, World War II antiaircraft artillery officer who took part and survived five amphibious landings in the Mediterranean.
10

Urban ecology in Christchurch: a reconciliation approach to enhancing native biodiversity on urban greyfields

Greenep, H. K. January 2009 (has links)
Traditionally New Zealand ecological research has focused on nature outside of cities, however, as with global trends, there is now more interest being given to the ecological functioning of cities and the potential they may hold for protecting native biodiversity. Traditionally, efforts to maintain biodiversity in urban areas have been restricted to remnants of native vegetation and restoration activities. Little attention has been given to how native biodiversity could be woven into the urban fabric in an ecologically meaningful way. One option, that is receiving much attention overseas, is to recruit underutilised urban spaces such as wasteland. A subset of urban wasteland, abandoned industrial areas usually awaiting development and other areas such as the railway buffer, are referred to here as greyfield. These are ephemeral sites that may sit between uses for as little as a few months to many years. Overseas, particularly in European countries, these have been recognised as important habitat for both native and introduced plant species. In New Zealand cities these support primarily introduced plants and their contribution to native biodiversity has been unknown. This thesis took an interdisciplinary approach to the question of whether urban greyfields might have potential value as biodiversity protection and conservation opportunity. Ecological methods were combined with an assessment of the planning framework to answer this question. iii Greyfields in Christchurch, New Zealand were surveyed to determine their current contribution to native biodiversity and whether they may act as urban analogues of natural habitats. Overseas research has shown that urban features such as pavements, walls and rooftops offer habitats analogous to cliffs and rocky habitats. Cities are therefore increasing the habitat exploitable by species whose natural habitats are geographically restricted. The Christchurch greyfields were assessed for their potential to act as analogues of four habitat types that have been categorised as historically rare in New Zealand: braided riverbeds, shingle beaches, rock outcrops and limestone outcrops. The findings suggest that urban greyfields, if managed appropriately, have the potential to support a wider range of native species Planning documents and biodiversity strategies written for Christchurch were assessed to see how well they facilitated non-traditional biodiversity enhancement initiatives, specifically the greyfield network for native biodiversity. A major finding here was a lack of information on how to enhance biodiversity where little of the natural features of the landscape were left and that this was creating a barrier to adopting more integrative approaches to enhancing native biodiversity. Finally, a plan to create a greyfield network for native biodiversity is proposed and suggestions are made as to minor changes to the planning framework that would more easily facilitate the uptake of novel biodiversity enhancement initiatives in the City.

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