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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.
31

A case study of environmental health in the South Durban basin.

Niranjan, Ivan. January 2005 (has links)
No abstract available. / Thesis (MPA)-University of Kwazulu-Natal, 2005.
32

Vulnerabilities to Seismic Hazards in Coastal and River Environments: Lessons post the Canterbury Earthquake Sequence 2010-2012, New Zealand

Kelland, Emma Jean January 2013 (has links)
Coastal and river environments are exposed to a number of natural hazards that have the potential to negatively affect both human and natural environments. The purpose of this research is to explain that significant vulnerabilities to seismic hazards exist within coastal and river environments and that coasts and rivers, past and present, have played as significant a role as seismic, engineering or socio-economic factors in determining the impacts and recovery patterns of a city following a seismic hazard event. An interdisciplinary approach was used to investigate the vulnerability of coastal and river areas in the city of Christchurch, New Zealand, following the Canterbury Earthquake Sequence, which began on the 4th of September 2010. This information was used to identify the characteristics of coasts and rivers that make them more susceptible to earthquake induced hazards including liquefaction, lateral spreading, flooding, landslides and rock falls. The findings of this research are applicable to similar coastal and river environments elsewhere in the world where seismic hazards are also of significant concern. An interdisciplinary approach was used to document and analyse the coastal and river related effects of the Canterbury earthquake sequence on Christchurch city in order to derive transferable lessons that can be used to design less vulnerable urban communities and help to predict seismic vulnerabilities in other New Zealand and international urban coastal and river environments for the future. Methods used to document past and present features and earthquake impacts on coasts and rivers in Christchurch included using maps derived from Geographical Information Systems (GIS), photographs, analysis of interviews from coastal, river and engineering experts, and analysis of secondary data on seismicity, liquefaction potential, geology, and planning statutes. The Canterbury earthquake sequence had a significant effect on Christchurch, particularly around rivers and the coast. This was due to the susceptibility of rivers to lateral spreading and the susceptibility of the eastern Christchurch and estuarine environments to liquefaction. The collapse of river banks and the extensive cracking, tilting and subsidence that accompanied liquefaction, lateral spreading and rock falls caused damage to homes, roads, bridges and lifelines. This consequently blocked transportation routes, interrupted electricity and water lines, and damaged structures built in their path. This study found that there are a number of physical features of coastal and river environments from the past and the present that have induced vulnerabilities to earthquake hazards. The types of sediments found beneath eastern Christchurch are unconsolidated fine sands, silts, peats and gravels. Together with the high water tables located beneath the city, these deposits made the area particularly susceptible to liquefaction and liquefaction-induced lateral spreading, when an earthquake of sufficient size shook the ground. It was both past and present coastal and river processes that deposited the types of sediments that are easily liquefied during an earthquake. Eastern Christchurch was once a coastal and marine environment 6000 years ago when the shoreline reached about 6 km inland of its present day location, which deposited fine sand and silts over this area. The region was also exposed to large braided rivers and smaller spring fed rivers, both of which have laid down further fine sediments over the following thousands of years. A significant finding of this study is the recognition that the Canterbury earthquake sequence has exacerbated existing coastal and river hazards and that assessments and monitoring of these changes will be an important component of Christchurch’s future resilience to natural hazards. In addition, patterns of recovery following the Canterbury earthquakes are highlighted to show that coasts and rivers are again vulnerable to earthquakes through their ability to recovery. This city’s capacity to incorporate resilience into the recovery efforts is also highlighted in this study. Coastal and river areas have underlying physical characteristics that make them increasingly vulnerable to the effects of earthquake hazards, which have not typically been perceived as a ‘coastal’ or ‘river’ hazard. These findings enhance scientific and management understanding of the effects that earthquakes can have on coastal and river environments, an area of research that has had modest consideration to date. This understanding is important from a coastal and river hazard management perspective as concerns for increased human development around coastlines and river margins, with a high seismic risk, continue to grow.
33

The mathematical modelling of the interaction between sprinkler sprays and the thermally buoyant layers of gases from fires

Gardiner, A. J. January 1988 (has links)
No description available.
34

Identifying the Impact of the Built Environment on Wildfire Property Damage in California

Makino, Takashi Michael 03 October 2013 (has links)
Wildfires are a natural hazard that present an increasing risk to communities in fire-prone areas. This study examines the impacts of the municipal-level built environment upon fire damages in California, a particularly fire-vulnerable state. This study uses a multivariate linear regression model to isolate the effects of the human built environment upon reported monetary wildfire damages. Reported monetary losses from wildfires for the years 2007 to 2010 are examined against relevant built environment variables, while statistically controlling for biophysical and socio-economic variables. The fully-specified regression model indicates that wildfire property damage is driven primarily by the built environment. Socioeconomic and biophysical variables contribute comparatively little explanatory power to the model. Findings from this study will be of particular interest to fire management officials, land developers, and urban planners interested in creating a more fire-resilient future for cities within California.
35

Pesticide use in rice cultivation in Tarapoto, Peru : pesticide residues in blood of farmers, usage behaviour, and health care practices /

Lange, Gun, January 2006 (has links) (PDF)
Examensarbete.
36

Variable importance in predictive models : separating borrowing information and forming contrasts /

Rudser, Kyle D. January 2007 (has links)
Thesis (150-154)--University of Washington, 2007. / Vita. Includes bibliographical references (p. 150-154).
37

Estimating the functional form of the effect of a continuous covariate on survival time

Holländer, Norbert. Unknown Date (has links) (PDF)
University, Diss., 2002--Dortmund.
38

The Control of Reproductive Hazards in the Workplace: A Prescription for Prevention

Ashford, Nicholas, Caldart, Charles C. January 1983 (has links)
As workers become more aware that occupational exposure to toxic substances can impair their ability to bring healthy children into the world. they will begin to focus on legal mechanisms for reducing reproductive hazards in the workplace. The authors explore the use of compensatory remedies and anti-discrimination laws to provide an impetusfor employers to provide safe workplaces. hey investigate using workerprotection laws to reach psychological injuries and harm to offspring. They also survey existing preventive tools such as injunctive relief and the right to refuse hazardous work
39

Coping With Delays And Hazards In Buses And Random Logic In Deep Sub-Micron

Skoufis, Michael N. 01 January 2009 (has links)
A new data capturing technique for a potentially coupled bus of lines is proposed that always accommodates fast operation. The proposed method utilizes multiple reference voltages available within a line's receiving logic and the initial conditions of the involved wires in order to determine early and accurately the transmitted data in the current cycle. The presented data reading technique rarely requires repeater insertion and it can considerably accelerate signal propagation. The introduced logic at the receiver-end of a victim wire entails an affordable area overhead. Experimental results are given in the 65nm CMOS process for interconnects of various lengths. An architecture is proposed that allows for data reading with fault detection capability on lines which are likely to operate under a potentially wide range of capacitive coupling. In order to develop such a methodology, multiple reference or threshold voltages in the receiving logic of the lines are considered instead of typically one. The proposed technique utilizes the additional reference voltages to evaluate whether an intermittent fault has occurred during the capture of the transmitted data. Some combinational logic is introduced on the receiver side to accomplish this task. The mechanism is initially illustrated on a line with one adjacent aggressor. Subsequently, the case of a line with two adjacent aggressors is discussed and it is shown how to generalize the technique for wide buses. In this work the efficiency of the detection mechanism is evaluated for both single and multiple faulty occurrences. A novel circuit to treat crosstalk induced glitches on local interconnects is presented. Design irregularities and manufacturing defects on wires may result in spurious electrical events that impact the reliability of the interconnect infrastructure. The proposed methods act by dynamically adjusting the threshold voltage of the receiving gate on the victim line. The proposed technique can be used in combination with encoding algorithms on data buses. A comparative study in the 180nm CMOS process is presented that supports the applicability of the approach. Transient faults due to radiation have become increasingly observable in combinational logic. This is due to the weakening of inherent protective mechanisms that logic traditionally held against such flawed spurious events. Further boosting of such effects is increasingly probable due to the interaction of transients appearing at the inputs of logic gates. Such multiple instances of transients can arise either because of re-convergent circuit paths or because of significant reduction in the critical charge of modern technologies. The latter, in particular, makes more than one circuit nodes susceptible to the same high energy ions. A static transient propagation is employed to address possible transient interaction and to compute its worst-case effects in logic. The quantified effects of interest are the maximum duration and slope of the resulting hazards at the circuit outputs. A hardening methodology is also proposed to protect combinational logic from such events. For this purpose, filtering circuits are inserted in logic and several placement algorithms are developed and evaluated.
40

Implications for Volcanic Hazards in the Central and Southern Cascades Based on Gas Emissions During Explosive Cinder Cone Activity

Walsh, Lucy 11 July 2013 (has links)
Volatile emissions from Cascades cinder cone eruptions have been well-documented; however the implications for understanding the effects that volcanic gases have on surrounding communities have not been addressed. This study examines the hazards from volatile degassing during explosive activity by (1) analyzing S, Cl, and F concentrations dissolved in olivine-hosted melt inclusions and matrix glass from cinder cones located in central Oregon and northern California, (2) estimating the mass of volcanic gas degassed during these eruptions, and (3) predicting gas concentrations downwind of the vent. Analyses reveal that the magmas degassed >88% S, <49% Cl, and <50% F during eruption, equating to a release of ≤4.5 Mt SO2, ≤0.2 Mt HCl, and ≤0.2 Mt HF. Predictions of gas concentrations downwind of the vent provides reassurance that the levels of volcanic gases were not high enough at the time of eruption to present acute or severe health hazards to nearby residents.

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