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Arresting vision : a geographical theory of Antarctic lightYusoff, Kathryn January 2005 (has links)
As a site at the margin of terrestrial systems, Antarctica disrupts the usual practices of visual representation. This thesis investigates, what I call, chronogeographical approaches to visual culture within the Antarctic terrain. The material and theoretical chronogeographies of vision are mapped through the action of light, to elucidate on the shifting terrain of form - that is the Antarctic landscape. Historically, the thesis explores how the 1980s anti-mining campaign, organised by environmental groups challenged the political and visual hegemony of the Antarctic Treaty Consultative Parties. The campaign highlighted the feedback between the circulation of images and initiatives to protect the Antarctic landscape. Situated within this visual economy, the thesis focuses on how representation demarcates abstract and imaginative spaces for the production of the landscape - creating fugitive images of Antarctic spatialities. The thesis follows the fugitive testimony of the image through fields of knowledge, from the arrest and flow of landscape to the aesthetics of mobility. Critical art practice is considered as an interstice that highlights the conditions under which landscapes are given visibility, both cognitively and optically. A stratum of histories, mappings and sitings, structure the investigation into the transmission, materiality, and memory embedded in different media employed in the production of Antarctica. Through this sedimentation of geographies, the thesis proposes that the limits of representation may be found in Antarctica. It is argued that this shattering of commonly available visual languages can be a means to aerate our creative explorations of place. From this site, broader issues about the economy of the visual and the limits of visibility are examined. The thesis concludes that only by attending to the complex geographies of the image can the geopolitical aesthetics of place be accounted for.
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The development of luminescence methods to measure thermal exposure in lithic and ceramic materialsSpencer, Joel Quintus January 1996 (has links)
Thermometric analyses provide extremely useful information about heated archaeological materials and fire-damaged modern structures. A number of non-luminescence thermometry methods have been developed for analysing pottery firing temperatures. However, many of these methods are limited in analysis range and accuracy, or are time consuming, expensive and complex. In addition to these techniques there are a number of thermoluminescence (TL) thermometry methods but they are also limited in analysis range and the majority have been developed for specific thermometry problems. The aim of this study was to investigate the use of thermoluminescence (TL) and photostimulated luminescence (PSL) methods to develop rapid, precise, inexpensive thermometry techniques that were applicable to a wide range of thermal events and materials from archaeological and modern contexts. A basic theoretical treatment of luminescence kinetics in silicate systems was undertaken to develop an understanding of TL glow curve alterations arising from thermal exposure. Kinetic studies showed that a combination of temperature and duration parameters is expected for single trap systems. Kinetic theory was developed to produce a new first order multi-trap system which provides a theoretical means of separating temperature and time components, which may be applicable to synthetic phosphors. Additionally heat transfer solutions were investigated to examine the temperature distribution in heated solids and TL instrumentation. Isothermal annealing experiments on IAEA-F-1 potassium feldspar showed a highly precise progressive thermal exposure monitor, whereby the position of the first rise of an annealed TL glow curve is characterised by a linear increase in temperature and a logarithmic increase in time. First order kinetic simulations and initial rise measurements demonstrated a continuous linear distribution of traps in IAEA-F-1 feldspar. Using a high temperature TL system (maximum temperature 700°C) the progressive thermometry method was successfully applied to separated feldspar minerals and polymineral samples from archaeological (ceramics, burnt stones and hearthstones) and modern (fire damaged concrete) materials. PSL excitation spectroscopy showed potential thermometric behaviour but for some samples the sensitivity of the system was too low. Pulsed infra-red PSL showed there may be a limited trap distribution over which a small range of thermal exposures will operate. Combined TL/PSL measurements showed it may be possible to deconvolute temperature and time parameters.
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Dust storm phenomena and their environmental impacts in KuwaitMohammad, Mohammad-Shafi Abdullah January 1989 (has links)
Dust storms are one of the significant phenomena in the desert areas of the world. It is internationally agreed that days with visibility below 1000 metres due to dust present in the air are a result of strong winds. As Kuwait is part of the Arabian desert, which is identified as one of the major dust sources, so dust storm occurrence is more frequent especially during summer. Dust storms in Kuwait are mainly associated with north and north westerly winds, which are locally known `Shamal'. That is because this wind crosses the Iraqi and Arabian deserts before reaching Kuwait carrying a huge amount of dust and sand. There are local dust sources within Kuwait which supply these winds with dust. Dust occurs in Kuwait in four main types: 1) Sand/dust storm 2) Rising dust 3) Suspended dust 4) Haze There are many factors which play an important role in the occurrence of dust in Kuwait, they include the following: 1) Kuwait's location within the great desert belt. 2) Lack of rainfall. 3) Lack of vegetation cover. 4) Surface air turbulence due to huge amounts of radiation. 5) Human activities such as over-grazing, off-road driving. Dust and sand storms have a bad effect on environment in Kuwait. The main aspects of the environmental impact of dust which have been focussed on in this thesis, are: 1) Dust effects on vehicle body parts and the role of dust storms in road accidents due to poor visibility. 2) Dust effect on house parts and buildings. 3) Dust effects on human health from inhaling the fine dust particles which contain many organic and non-organic material. These materials, which are carried by dust, cause various types of allergies especially with respiratory system. There are many methods which have been used to reduce the amount of dust which is raised up in the air by strong winds. But it seems the most suitable method is tree planting which has many positive effects other than stabilising sand.
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Choosing environmental policy instruments : case studies of municipal waste policy in Sweden and EnglandPersson, Åsa Maria January 2007 (has links)
European governments have during the last couple of decades shown an interest in new types of environmental policy instruments (EPIs) such as environmental taxes, tradable permit schemes and voluntary approaches, as opposed to relying on traditional forms of regulation. The interest in so-called ‘new’ EPIs (NEPIs) has led many governments to commit both to a more diverse EPI mix and to a policy process characterised by procedural rationality, in terms of considering a wide range of alternative instruments and assessing them in a systematic and transparent way. The first aim of this thesis is to examine the success of the quest for NEPIs at the national level in the field of municipal waste policy in two countries; the UK (England) and Sweden. In addition to mapping out EPI diversity, two contrasting theories on the pattern of adoption of instruments over time are evaluated, specifically focusing on the degree of coercion associated with EPIs. It is found that the waste policy mix in England has become more diverse, while the Swedish mix is characterised by a higher degree of coercion. The second aim is to analyse whether the instrument choice process has become more procedurally rational, and, if so, conducive to the adoption of NEPIs. A range of instrument choice theories at the macro-, meso- and micro-levels drawn from the public policy and political science literature are used to explain whether the ideal of procedural rationality is achievable or not. A case study methodology is used, in which the processes leading to the landfill allowance trading scheme (LATS) in England and and the waste incineration tax in Sweden are studied. It is found that the procedural rationality was higher in the England case, but that it is not a necessary nor sufficient cause for adoption of a NEPI.
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Who bites back first? : malaria control in Ghana and the politics of co-existenceBeisel, Uli January 2010 (has links)
No description available.
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Likelihood measure for environmental modellingSmith, Paul J. January 2007 (has links)
No description available.
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Small-scale heterogeneity in sediments : experimental and modelling investigationsStockdale, Anthony January 2008 (has links)
This thesis consists of several studies relating to small-scale heterogeneity in sediments. The principal aim was to further our understanding of processes occurring at microniches. The individual studies consist of: 1) a critical review of previous studies of microniches that used probes with high spatial resolution and modelling approaches; 2) an experimental study of analysis of oxyanions in sediment at high resolution that applied a newly developed preparation method for a combined AgI/FeOOH binding phase, to investigating processes occurring at a sulphidic microniche within a freshwater sediment; 3) analysis of the relationship between trace metal (cobalt) and iron and manganese in a marine sediment using DGT, although this is not directly related to microniches, these data are useful in modelling the release of microniche trace metal from authigenic oxides; 4) the development and application of a three-dimensional diagenetic model to investigate conceptually the geochemical behaviour of microniches under different conditions, and to interpret modelled observations in terms of data from the literature and known trace element geochemistry. The key results/conclusions from both the laboratory and modelling studies are: 1) for a freshwater sediment, depletions in anions (of P, V, As) at a microniche of elevated sulphide were observed and the behaviour of phosphate at this niche was attributed to uptake associated with elevated activity of sulphate reducing bacteria; 2) modelled scenarios, with varying microniche properties, were shown to be relevant to experimental observations reported in the literature. The preferential deposition of FeS at the edge of microniches (with lifetimes of 2.5-5 days), forming ‘crustal’ deposits was demonstrated. The modelled data indicated that microniches may be significant in terms of the formation of some trace element sulphides. This thesis also contains an assessment of the significance of microniche processes and a discussion of priorities for future work.
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Environmental assessment of the south coast of Sri Lanka, with special reference to the 2004 tsunamiVenkatachalam, Alicia Jane January 2010 (has links)
Following the 2004 tsunami in Sumatra, Sri Lanka experienced >30,000 confirmed deaths and disruption of livelihood. Damage to coastal ecosystems was less than anticipated, especially in comparison with reported impacts from unsustainable development. This research examines tsunami related damage against a background of anthropogenic pressures. Fishery changes were determined through interview of three generations of fishers targeting frigate tuna. Significantly higher values for best day’s catch and largest specimen ever caught were obtained by older fishers than younger ones. Values were also significantly higher during early years, providing clear evidence of resource decline and the ‘shifting baseline syndrome’. Most fishers reported posttsunami decline in frigate tuna, but mainly from a larger new generation of fishers, rather than extra boats provided by aid money or (direct or indirect) biophysical impacts from the tsunami. The number of boats post-tsunami increased significantly in all research areas, which could result in further catch decline. The perceptions of 500 Sri Lankan fishers about the influence of risk factors on tsunami death toll and house damage are quantified). Mangroves, coral reefs and sand dunes afforded protection against tsunami damage (67–94% of fisher responses), as did housing and roads. Fishers believed rivers/estuaries, concave coastlines and hotels exacerbated impacts. For comparison, multi-variable models for death toll, housing damage, inundation area and distance are built, incorporating both natural and developmental risk factors. Bathymetry is the only factor significantly associated with all indicators of impact. Mangroves and marsh were not a significant factor in final multivariable models. However, in terms of inundation, sand dunes were identified as protective, while bodies of water exacerbated damage. The extent of agreement and variance between modelling results and the opinions of fisher questionnaires is critically examined. Research findings highlight the need for better coastal management. While the role mangroves in tsunami protection remains equivocal, their known role in providing many other ecosystem services suggests that mangroves warrant greater conservation attention in Sri Lanka, in the face of coastal development pressures. Coastal policy and conservation priorities should be influenced by scientific research (e.g. the tsunami model in this thesis) as well as traditional ecological knowledge and opinions from indigenous people. Factors shown to provide tsunami protection often cannot be altered by human intervention (e.g. topography and bathymetry). However, sand dunes could potentially be preserved to reduce future impacts. Tsunamis are rare events and further research should be carried out to determine which risk factors are important for more frequent events (e.g. monsoon). The needs of coastal communities should always remain paramount in considerations of future tsunami and environmental policies.
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Assessing the effectiveness of landfill restoration and remediation at a closed landfill siteLing, Sarah R. A. January 2007 (has links)
This research project was established to investigate the varying environmental impact of a landfill waste mass after the installation of a fully engineered landfill capping system. Nant-y-Gwyddon Landfill Site is a waste disposal site situated in the Rhondda Fawr in South Wales, UK. The site was established on an area of high ground overlooking the densely populated valley floor. The key environmental body at risk from the site was identified as the layered aquifer system supported by the cyclical geological strata dominated by sandstone aquifers separated by less permeable siltstone, mudstone and coal seams. The research adopts an integrated approach, where the understanding of the changes occurring in the waste mass are directly linked to predicted changes in the contamination levels in the groundwater system. Emphasis is also given to the mechanisms for contaminant transport between the waste mass and the environmental systems. As such the entire landfill system including the surrounding environment is considered as a set of closely interconnected systems. A monitoring system was designed to observe the changes occurring to the waste mass in terms of leachate level and saturation conditions after the installation of the landfill cap in an attempt to assess the changing leachate generation rates and quality within the waste mass. The key findings from the waste mass are then used to interpret variations in contaminant levels in the groundwater systems. Geophysical investigations highlight the extent of the leachate contamination detected in the groundwater hydrogeologically down gradient of the waste mass. The findings from groundwater monitoring are then used to develop a hydrogeological numerical model for the site using the program Visual MODFLOW. The key findings from groundwater monitoring and modelling highlight the importance of the unsaturated zone beneath the site in providing a source of contaminants which are mobilised during increased groundwater levels triggered by rainfall events. The majority of the contaminant loading was determined to be sourced from the area where a direct pathway exists between the waste mass and the Main Aquifer system. Predictions for future trends of contamination levels are then made in response to the findings and show a dynamic system intrinsically linked to the development of the waste mass and the meteorological conditions on site.
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Aeolianites and palaeosols in Israel : luminescence chronology and relationship with Eastern Mediterranean climatesEngelmann, Anette January 2004 (has links)
Aeolianites and palaeosols on the Meditcrranean coastal plains of Israel were investigated with luminescence dating in order to explore the sedimentological evidence for climate change in the area and the response to it. The dated samples were taken from sites between the towns of Haifa and Netanya South, which are located in a quarry near the town of Habonim and further towards the coast, in a quarry North of the town of Hadera and further towards the coast as well as at the coastal cliff and in a sewage gully by the town of Netanya South. The aims of this study were to correlate aeolianite and palaeosol exposures along the Mediterranean coast, to establish a chronology for a climatological interpretation, and also whether aeolianite formation and palaeosol development could be correlated with major climate events of the Late Pleistocene in the Eastern Mediterranean. Over 80 samples were collected from various sites, covering exposures from North to South and also from East to West. They were dated with infrared optical stimulated luminescence (IR-OSL) and thermoluminescence (TL). In addition radio fluorescence spectra were obtained from some of the samples and also their equivalent doses were determined with infrared radiofluorescence (IR-RF) The chronology established through the luminescence dating results showed that aeolianite formation and palaeosol development in the Carmel and Sharon coastal plains are connected with the cyclical occurrence of enhanced rainfall over the Mediterranean. These conditions, which also cause the Mediterranean sapropels to form, are characterised by a sudden increase of precipitation. The rainfall lessens over the time of the episode but temperatures increase. It is likely that most of the soils in the coastal plains developed during the humid conditions of the rainfall episodes, while sand accumulation and aeolianite formation took place during the arid conditions at the end of the rainfall episodes or shortly afterwards. A new climate-event-stratigraphical model for the correlation of the deposits is suggested.
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