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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.

Numerical analysis of thermal enhanced oil recovery methods

Youtsos, Michael Spiro January 2014 (has links)
No description available.

A Study of fume particle deposition

Goerg, Kristin A. 01 January 1989 (has links)
No description available.

Project management process for disaster recovery projects

Gonzales, Steven Anthony 14 February 2011 (has links)
A project is an organized endeavor aimed at accomplishing a specific nonroutine or low-volume task (Shtub, Barb, & Globerson, 2005). Natural hazards particularly hurricanes and flooding do not exactly match this definition, but the recovery from them does. Recovery is not only about restoration of structures, systems and services – although they are critical. A successful recovery is also about the individuals and families being able to rebound from their losses, and sustain their physical, social and economic well-being (Department of Homeland Security, 2010). To be able to do this requires a comprehensive disaster recovery plan comprised of consistent action to be taken before, during and after a disaster. Flooding and wind related damages from hurricanes and tropical storms create the most widespread natural hazard disasters resulting in billions of dollars in property losses each year. Southeast Texas is vulnerable to flooding because of its proximity to the Gulf of Mexico and its flat terrain. 2004, 2005, and especially the 2008 hurricane season have highlighted the need for additional guidance, structure and support specifically oriented to long-term disaster recovery. The 2008 hurricane season was particularly active for Texas with a tropical storm and three named hurricanes. Hurricane Ike was the largest to hit the Texas coast in history and the third most destructive in the nation’s history. An estimated total damage of $29 billion for the 2008 hurricane season devastated Texas (Office of the Governor of the State of Texas, 2008). Luckily, the recovery efforts for Hurricane Ike have been marked by positive outcomes when compared to previous responses to events, but more work could have been done in the pre-disaster planning of an event. This thesis will outline a process that will look at ways to mitigate the hazard by planning long-term to lessen the recovery time and lead to a more sustainable community by hardening infrastructure and strengthening residential building codes in anticipation of future disasters. / text

Modeling Dynamics of Post Disaster Recovery

Nejat, Ali 2011 August 1900 (has links)
Natural disasters result in loss of lives, damage to built facilities, and interruption of businesses. The losses are not instantaneous rather they continue to occur until the community is restored to a functional socio-economic entity. Hence, it is essential that policy makers recognize this dynamic aspect of the incurring losses and make realistic plans to enhance the recovery. However, this cannot take place without understanding how homeowners react to recovery signals. These signals can come in different ways: from policy makers showing their strong commitment to restore the community by providing financial support and/or restoration of lifeline infrastructure; or from the neighbors showing their willingness to reconstruct. The goal of this research is to develop a model that can account for homeowners’ dynamic interactions in both organizational and spatial domains. Spatial domain of interactions focuses on how homeowners process signals from the environment such as neighbors reconstructing and local agencies restoring infrastructure, while organizational domain of interactions focuses on how agents process signals from other stakeholders that do not directly affect the environment like insurers. The hypothesis of this study is that these interactions significantly influence decisions to reconstruct and stay, or sell and leave. A multi-agent framework is used to capture emergent behavior such as spatial patterns and formation of clusters. The developed framework is illustrated and validated using experimental data sets.

An empirical assessment of factors precluding recovery of sauger in the lower Yellowstone River movement, habitat use, exploitation, and entrainment /

Jaeger, Matthew Edward. January 2004 (has links) (PDF)
Thesis (M.S.)--Montana State University, 2004. / Title from PDF title page (viewed Jan. 6, 2005). Includes bibliographical references (p. 57-67).

Recovery Planning Under Canada's Species at Risk Act

Brassard, Christopher January 2014 (has links)
One of the integral components of Canada’s Species at Risk Act (SARA) is recovery planning for threatened, endangered, or extirpated species in Canada. The recovery planning process is guided by recovery strategies, to be published within one year of listing for endangered species and within two years of listing for threatened or extirpated species, though publication has rarely met statutory timelines. Here I investigate factors associated with recovery strategy completion as well as factors associated with strategy content, specifically recovery feasibility, information gaps, and critical habitat identification. Despite significant delays in strategy publication, I find no evidence of internal prioritization of species for strategy completion, with only administrative factors retained in predictive models; species listed on Schedule 1, for which the Department of Fisheries and Oceans (DFO) or Parks Canada Agency (PCA) is the Responsible Authority, or which there was a smaller backlog of due strategies one year after listing were more likely to have recovery strategies submitted on time. Analysis of factors associated with recovery feasibility show a higher likelihood of feasible recovery for species for which critical habitat is identified, the DFO or PCA is the Responsible Authority, there are more identified information gaps, or for which the recovery strategy contains a section on potential socioeconomic conflict. There were fewer identified information gaps in recovery strategies for those species for which recovery strategies were published after the judgments of the Nooksack Dace (ND) and Greater Sage-Grouse (SG) court proceedings, there was a greater time elapsed between strategy due date and date of draft publication, or whose range does not fall on a provincial or federal protected area. Pre-ND and SG court judgements, critical habitat was less likely to be identified for species with a lower threat status, species included in multi-species or ecosystem plans, or species not found within provincial or federal protected areas. None of these biases were detected post-judgement, however, as rates of identification increased significantly and only recovery feasibility was associated with CH identification. These results point to some potential problems in the recovery planning process as currently implemented under SARA, and inform recommendations as to how these might be addressed.

The dynamics and control of in-situ combustion

Young, Tobias J. January 1997 (has links)
Improved oil recovery (lOR) techniques target the 60% of oil left behind by primary and secondary methods (those that utilise the natural energy of an oil reservoir). Air injection in situ combustion (lSC) is a thermal lOR technique used in general to increase the temperature in a reservoir and in turn reduce the viscosity of the oil. This increases the mobility of the oil and can lead to significant improvement in recovery factors. The process is complex and much work is needed to improve modeling capabilities essential for reservoir management. To investigate high pressure air injection a combustion tube facility has been commissioned and four in situ combustion tube tests completed. This involved the development of data acquisition and control software (lsc View) to fully automate the air injection facility. The ISC tests were carried out with a West Shetland Clair crude oil of 19.7°API and air injection fluxes between 12 and 70m3/m2hr and pressures between 50 and 100 bar. Post-mortem analysis of the burned cores showed 100% oil displacement in areas of core swept by the combustion front. In these areas the amount fuel burned varied between 4.6 and 15.3 %OOIP (original oil in place). The combustion front temperatures varied between 450°C and 730°C. It was found that combustion front temperature increased with air injection flux. The combustion front velocity varied between 10.4 and 22.2cmlhr. The combustion front velocity was observed to increase with pressure thus the combustion front velocity and hence propagation of the combustion front was shown to be reaction rate dependent. History matching of the ISC tests was completed using the STARS simulator (Computer Modeling Group) a fully implicit non isothermal reservoir simulator. The simulations showed that when the grid size approached that of the actual reaction zone then the kinetics at different pressures did not change. Therefore, at this grid scale, the kinetic parameters used for a pseudo component representation of the oil can be applied as if it were a pure component, independent of pressure.

Mathematical modelling of in-situ combustion for enhanced oil recovery

Davies, R. January 1988 (has links)
In-situ combustion is an oil recovery technique in which air, or oxygen enriched air is injected into a reservoir in order to displace the oil. Under suitable conditions the oxygen will burn with part of the oil, raising the temperature of the reservoir and reducing the viscosity of the oil, hence allowing it to flow more easily. A serious problem with mathematical modelling of in-situ combustion is that of flame extinction due to grid block size effects. When modelling a field scale process using finite difference techniques the grid block size will be far larger than the flame length. Since parameters such as temperature and saturations are averaged over a grid block they will be misrepresented in the Arrhenius reaction rate equation, and the flame may die out. The approach taken to overcome the problem is to decouple the flame from a conventional finite difference simulator and solve separately for the reaction rate and flame velocity. This is achieved using a steady state analysis that applies a reduced set of the conservation equations in a moving frame over the flame region, and solves the resulting eigenvalue problem using a shooting method. The reaction rate and flame velocity determined by the steady state analysis are then used to apply the 'thin flame' technique to the conventional simulator. This treats the flame as a moving heat source and displacing pump, travelling through the domain with the velocity obtained by the steady state analysis. The steady - state analysis is compared with experimental results glvmg good agreement for the flame parameters. The thin flame method produces excellent agreement with the conventional simulator on laboratory scale simulations, and on field scale simulations it greatly reduces the problems associated with grid block size effects.

Fog formation in rapidly cooled gas-vapour mixtures

Miller, Andrew David January 2000 (has links)
No description available.

Treatment of leather effluents and dye solutions using electrolytic techniques

Goswami, Nimai Chandra January 2002 (has links)
No description available.

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