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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.
891

Non structural flood mitigation in Canada : linking the resources of today with a strategy for tomorrow

Slater, Alyson 05 1900 (has links)
Flooding poses one of the greatest natural hazard dangers to Canadians. As human populations increase and concentrate in areas vulnerable to floods, and uncertainty about future flood risk increases with the possibility of a changing climate, major urban communities, coastal settlements and communities located within floodplains are faced with an even greater risk of floods in the coming years. Canada's policies and practices towards flood control are best described as ad hoc, and have developed over the years in response to experiences with floods. No national scale flood damage reduction program exists, and there is currently no opportunity for Canadian homeowners to purchase flood insurance. This study specifically examines how a national mitigation strategy, focused mainly on non structural techniques could help decrease damages from floods in Canadian communities. The strategy proposed here is theoretically based in EPC and IBC suggestions for a greater national mitigation strategy, as well as IDNDR research, and federal, provincial and municipal goals for sustainable development and sound land use planning objectives. Ideally, a successful non structural flood mitigation strategy for Canada would address issues at the national scale, yet be implementable at the local level in accordance with community needs, risk characteristics, and local expertise. The strategy proposed here would maximize the efficiency of federal resources and private industry as well as allow local expertise and existing mitigation schemes to be formalized, bolstered and improved. There are three major components of the non structural flood mitigation strategy. Risk avoidance measures such as early warning systems, land use and resource planning and ecological conservation all work towards reducing the chances of a dangerous flood occurring. Risk spreading measures help communities deal with flood risks by improving equity and accountability, they include tax incentives, disaster financial assistance, and flood insurance. Lastly, vulnerability reduction measures help reduce damages if a flood were to strike, and these include enforcement of building codes and the maintenance of existing protective infrastructure. An integrated, non structural flood mitigation strategy would require basin-wide cooperation between all levels of government, citizens and the private sector. This strategy is also an opportunity for communities and individuals to meet goals of environmental conservation and sustainable development. The focus in this study lies on the mitigation tools, although it is the overall process of inserting the premise of mitigation into all land use and planning decision making processes that will be the key to successful flood mitigation strategies in Canadian communities.
892

Methods for estimating reliability of water treatment processes : an application to conventional and membrane technologies

Beauchamp, Nicolas 11 1900 (has links)
Water supply systems aim, among other objectives, to protect public health by reducing the concentration of, and potentially eliminating, microorganisms pathogenic to human beings. Yet, because water supply systems are engineered systems facing variable conditions, such as raw water quality or treatment process performance, the quality of the drinking water produced also exhibits variability. The reliability of a treatment system is defined in this context as the probability of producing drinking water that complies with existing microbial quality standards. This thesis examines the concept of reliability for two physicochemical treatment technologies, conventional rapid granular filtration and ultrafiltration, used to remove the protozoan pathogen Cryptosporidium parvum from drinking water. First, fault tree analysis is used as a method of identifying technical hazards related to the operation of these two technologies and to propose ways of minimizing the probability of failure of the systems. This method is used to compile operators’ knowledge into a single logical diagram and allows the identification of important processes which require efficient monitoring and maintenance practices. Second, an existing quantitative microbial risk assessment model is extended to be used in a reliability analysis. The extended model is used to quantify the reliability of the ultrafiltration system, for which performance is based on full-scale operational data, and to compare it with the reliability of rapid granular filtration systems, for which performance is based on previously published data. This method allows for a sound comparison of the reliability of the two technologies. Several issues remain to be addressed regarding the approaches used to quantify the different input variables of the model. The approaches proposed herein can be applied to other water treatment technologies, to aid in prioritizing interventions to improve system reliability at the operational level, and to determine the data needs for further refinements of the estimates of important variables.
893

Transportation asset management and climate change: an adaptive risk-oriented approach

O'Har, John Patrick 17 September 2013 (has links)
Transportation Asset Management (TAM) systems are in use at many transportation agencies both in the United States and around the world. These asset management systems serve as strategic resource allocation frameworks and their degree of implementation and maturity varies. Climatic change, with its potentially adverse impacts on both the built and natural environments, has become of increasing concern around the globe. Given the uncertainties associated with changing climatic conditions, transportation agency stakeholders utilize risk-based decision-making approaches to identify climate change impacts that pose the greatest risk to transportation infrastructure assets. In conjunction with criticality assessments, emerging conceptual frameworks seek to identify higher-risk infrastructure assets, which are both critical to system operations and vulnerable to potential climate change impacts, through standalone study efforts. This research develops a risk-oriented decision-making framework to identify vulnerable, higher-risk transportation infrastructure assets within the context of existing transportation asset management systems. The framework assesses the relative maturity of an agency’s transportation asset management system and provides guidance as to how an agency’s existing tools and processes can be used to incorporate climate change considerations. This risk-based decision-making framework is applied to three case studies: one at the Metropolitan Atlanta Rapid Transit Authority, another at the Metropolitan Planning Commission in Savannah – Chatham County, and a statewide case study at the Georgia Department of Transportation. The results of this research demonstrate that readily-available climate projection data can be analyzed and displayed geospatially so that the potential impacts of climatic change on transportation infrastructure can be determined for specific geographic regions. In addition, existing roadway and bridge infrastructure datasets can also be displayed geospatially. The framework uses geospatially-referenced roadway and bridge asset data and multi-criteria decision analysis procedures to develop and visually display criticality scores. Overlaying climate projection data and criticality data helps identify higher-risk transportation infrastructure assets. This research demonstrates that climate change considerations can be effectively incorporated in existing decision-making processes at various levels of maturity of formal TAM systems, making this more broadly accessible to agencies and communities with potential climate hazards.
894

A BOTTOM UP APPROACH TO EVALUATE RISK ASSESSMENT TOOLS FOR DRINKING WATER SAFETY IN FIRST NATIONS COMMUNITIES

Levangie, Janice Catherine 05 October 2009 (has links)
Safe drinking water is a basic need; and risk assessment tools may assist in prioritizing actions to improve water safety. The objective of this research was to determine the appropriateness of current risk assessment approaches for First Nations drinking water systems. Criteria to evaluate risk assessment approaches were developed by combining common elements from literature, key informant interviews, and surveys. The criteria were compared against selected tools for drinking water risk assessment, including tools developed by Australia, Montana, Indian and Northern Affairs, and the University of Guelph. None of the tools, as available, met all of the criteria. Important considerations were found to include the operator, monitoring and recordkeeping, maintenance, technical considerations, emergency response plans, and source water protection. The tools were generally weak in assessing some potential challenges facing small, remote, and First Nations communities; including financial constraints, and taking a holistic view of water. / Note: this thesis was also submitted in hard-copy to Graduate Services
895

Bioaccessibility of metals in Toronto city parks

Dakane, Abdulkadir 18 December 2012 (has links)
The purpose of this work was to estimate metals bioaccessibility in soil samples from 15 city parks in Toronto, Ontario, Canada. Total metals concentrations were analyzed to identify contaminants that exceeded the Canadian Council of Ministers of the Environment (CCME) guidelines for residential/parkland use. Arsenic, barium, cadmium, cobalt, copper, lead, nickel and zinc were of particular interest as they have been known to have major effects on human health. Metal concentrations were below the CCME guidelines except for lead at three of the parks. Lead, copper and cadmium bioaccessibility in the soil samples as determined by an in-vitro physiologically based extraction test (PBET) were relatively high. Based on linear regression analyses there were no significant relationships between total metals and soil properties such as pH and total organic carbon (TOC). Generally there was negative correlation between metal bioaccessibility and TOC and positive correlation between bioaccessibility and soil pH.
896

Activity-based life-cycle assessments in design and management

Emblemsvåg, Jan 08 1900 (has links)
No description available.
897

Gestion du risque sécuritaire et prédiction des incidents disciplinaires : la contribution des modèles d'importation, de privation et du LS/CMI

Charton, Thibault January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
898

An evaluation of approaches adopted by various departments in implementing integrated risk management in the Eastern Cape provincial government.

Jabavu, Simlindile Wellington. 27 November 2013 (has links)
The current business environment demands a more integrated approach to risk management due to the complex interrelationship and reliance across all divisions of an organisation. It is no longer sufficient to manage risk by individual or functional area. Organisations around the world now benefit from a more comprehensive approach to dealing with all risks. The study has been influenced by the Treasury Board of Canada Secretariat's (TBS) Integrated Risk Management Framework (IRM). Its aim is to promote and increase awareness of IRM across all departments in the Eastern Cape Provincial Government (ECPG). The study establishes progress towards implementation of IRM. The research scope covered thirteen government departments in the Eastern Cape. The study includes researching recent best public and private integrated risk management practices, both internationally and locally. The approach included development of a questionnaire on best practices and on principles of Integrated Risk Management based on TBS Integrated Risk Management Framework. Interviews were conducted and results documented to understand perceptions of the adequacy of current risk information in various departments and to discuss possible improvements to IRM. The process of collecting data for this study allowed information sharing with each department regarding current IRM Practices, and stimulated discussion on the nature and importance of IRM and actions that could move IRM forward. The research highlights key elements of IRM and establishes the progress by departments in implementing these elements. It also focuses on techniques and approaches that are used by the departments in dealing with IRM implementation. It uses Risk Management Maturity Continuum developed by Deloitte & Touche to determine extend to which departments have implemented their IRM. Lastly, the study highlights tools and techniques for strengthening of implementation of IRM based on best practices and conclude by making recommendations. / Thesis (MBA)-University of KwaZulu-Natal, 2006.
899

Conditions associated with levels of allergens and fungal aerosols in selected homes of selected primary school children in Durban.

Jafta, Nkosana. January 2007 (has links)
This indoor environment study formed part of the South Durban Health Study (SDHS) that investigated the health effects of exposure to ambient air pollution. Homes of children from seven communities corresponding schools were recruited to participate. This study was designed to determine characteristics in the homes that are associated with higher or lower levels of allergens and fungal aerosols. Homes were inspected using a field tested walkthrough checklist to collect data on home characteristics associated to adverse health effects. The characteristics include dampness, visible mould, type of flooring, type of bedding, type of heating systems, and building type and age. Dust samples for allergen analysis were collected from the bedding and the floor of the sleep area used by the children. Air samples from all rooms in the house were collected on malt extract agar, the media used for identifying and quantifying airborne fungal aerosols. More than 70% of the homes were single units standing on their own, 20% were attached houses (flats or apartments) and the rest (10%) were informal houses. Construction material of the homes comprised of bricks (93%), wood (5%) and other material (2%) such as corrugated iron of which 94% were formally constructed. Dampness signs were observed in 51% of the homes and visible mould growth 13% of them. In all them, at least one characteristic that is hypothetically associated to elevated house dust mite allergens was found. Levels of mould (Asp f 1) allergen and house dust mite (Der p 1 and Der f 1) allergen were comparable to levels found in other parts of the world. Asp f 1 allergen levels ranged between 0.32-1.379g/g and Der p 1 and Der f 1 allergen levels ranged from undetectable to 49.61 and from undetectable to 39.319g/g of dust respectively. Some home characteristics from walkthrough checklist were associated with Asp f 1, Der p1 and Der f 1 allergen levels when simple regression analysis was performed. Asp f 1 was significantly associated with single family home [OR= 0.004 (95%CI 0.004–0.35)] and polyester filled pillows [OR= 0.07 (95%CI 0.01– 0.61)] in logistic regression models. Der p 1 allergen was associated with observed extent of roof dampness [OR= 0.33 (95%CI 0.13–0.81)]. Fungal aerosol mixture consisted of Cladosporium spp. as the predominant genus together with other genera such as Aspergillus, Penicillium and Fusarium were, to a lesser extent, identified in the samples from the homes. Mean concentration of total indoor fungal aerosol of indoor and outdoor were 1108 CFU/m3 and 1298 CFU/m3 respectively. Individual genera of fungi in the childrens sleep area had mean levels of 783 CFU/ m3, 30CFU/ m3, 64CFU/ m3, 48CFU/ m3 and 43 CFU m3 for Cladosporium spp., Aspergillus spp., Penicillium, spp., Fusarium spp. and Rhizopus spp. respectively. Simple regression showed some conditions in the homes to be predictors of higher levels of total fungal aerosols. In a linear regression models, total outdoor fungal levels were a protective effect on total indoor fungal levels [C= 0.542 (95%CI 0.437–0.647)] whilst homes with hard floors had about 25 CFU/m3 [C= 5.235 (95%CI 0.557–9.913)] in the homes were significantly associated. This study showed the need to adapt observational instrument/ checklist/ questionnaire to suit the environment or the study area of interest. As other studies and findings indicated, the best way to assess exposure to biological pollutants indoors needs a combination of two or more methods, i.e. direct and indirect methods. / Thesis (MMedSc-Occupational and Environmental Health)-University of KwaZulu-Natal, 2007.
900

Ambient sulphur dioxide (SO2) and particulate matter (PM10) concentrations measured in selected communities of north and south Durban.

January 2006 (has links)
The industrial basin in the south of Durban is an area of ongoing contention between the residents and major industries, regarding environment health issues especially poor air quality resulting from industrial air pollution. This region is a result of poor urban planning that began in the early 1960's which saw rapid industrialisation alongside expanding communities, which has now resulted in a major environmental dilemma for the city of Durban, eThekwini Municipality. Durban is seen as a key area of growth in South Africa: it has the busiest harbour on the continent; it is a regional hub of the chemical industry and a major motor and metal manufacturer centre; and Durban's population continues to grow at ~4% per annum, all of which are destined to have significant environmental impacts. As part of a large epidemiological study and health risk assessment in this industrial basin, particulate matter smaller than 10 microns (PM10) and sulphur dioxide (S02) were measured in seven community sites across Durban: four in the South, (Wentworth, Bluff, Merebank and Lamontville) and three in the north (Kwamashu, Newlands East and Newlands West). The south sites are located in an industrial basin near two petroleum refineries and a paper mill, while the north comparison sites are ~25 km North West from major industries in the Basin. 24 hour PMIO samples were collected gravimetrically every day during four, three-week intensive phases and thereafter every 6th day using high, medium and low volume samplers. S02 was monitored every 10 minutes with active continuous analysers (European monitor labs and API) according to internationally accepted methods. Rigorous quality assurance methods were followed for both pollutants. S02 followed a distinct spatial distribution where the mean difference in S02 concentrations between the southern and the northern region was 6.7 ppb, while for PMIO similar concentrations were found across all sites with the highest mean concentration at Ngazana in the north (59 Ilg/m3) > Assegai in the south (~58 Ilg/m3) with all other sites ~ I to 10 Ilg/m3 less in mean concentration. S02 diurnal variations display two maxima from 5:00AM to 10:00AM being repeated in the latter part of the day from 20:00PM to 24:00PM. Seasonal pattern of PMIO and SOz to a lesser extent, display very similar mean variations for all sites - the highest levels seen in the colder months of May; June, July of 2004 and 2005. Weak to strong intersite correlations were found for SOz ranging from 0.16 to 0.22 among the south sites; 0.06 to 0.64 among the north sites, while PM10 ranged from 0.73 to 0.88 among the south sites and 0.86 to 0.91 among the north sites. A cross regional correlation of PMIO by sites displayed a moderate to strong correlation ranging from 0.73 to 0.88, while intrasite SOz with PMIO correlations displayed weak to moderate correlations from 0.35 to 0.53. Meteorological conditions wind speed, temperature, pressure and humidity differed across Durban. The difference in temperature and humidity between "summer" and "winter" was on average, approximately 7 °c and 10-15% respectively. These temperature and humidity patterns closely track the increase in SOz and PM10 during "winter" explaining the effects of winter inversions on pollutant levels. Also of interest is the variability of meteorological parameters between south and north Durban with the two regions being 35 km apart. Meteorological conditions impact differently on each pollutant e.g. rain is more likely to decrease PMIO concentrations than it would SOz In general relationships between pollutants and meteorological parameters differ on a site-bysite basis. For instance, wind direction at Assegai increases SOz levels whereas wind direction at Ngazana decreases SOz levels. Another independent variable that proved to be a consistent and important predictor for SOz and PM10 across most sites was the previous day's pollution events; this was a much stronger predictor for PM10 rather than SOz. These findings suggest that pollutants are not fully removed from the atmosphere during a 24 hour period and that the previous day's pollution levels will contribute to current levels, a finding that has important implication when implementing early warning pollution systems as envisaged for the Durban South Basin. / Thesis (MMed)-University of KwaZulu-Natal, 2006.

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