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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

The impact of reservoir properties on mixing of inert cushion and natural gas in storage reservoirs

Srinivasan, Balaji S. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains vii, 88 p. : ill. (some col.), map (part col.). Includes abstract. Includes bibliographical references (p. 47-49).
2

Impact of injecting inert cushion gas into a gas storage reservoir

Lekkala, Sudheer R. January 2009 (has links)
Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains vii, 40 p. : col. ill. Includes abstract. Includes bibliographical references (p. 39-40).
3

Analysis of underground thermal energy storage systems with ground water advection in subtropical regions

He, Miaomiao., 何苗苗. January 2007 (has links)
published_or_final_version / abstract / Mechanical Engineering / Master / Master of Philosophy
4

Analysis of underground thermal energy storage systems with ground water advection in subtropical regions

He, Miaomiao. January 2007 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
5

Analysis of underground thermal energy storage systems with ground water advection in subtropical regions /

He, Miaomiao. January 2007 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2007. / Also available online.
6

REPORT ON AN INTERNSHIP WITH HANDEX OF ILLINOIS, INC MARCH 2001 THROUGH AUGUST 2001

Molholm, James M. 11 December 2002 (has links)
No description available.
7

Multiphase flow and mass transport through porous media

Snyder, Kevin P. 17 January 2009 (has links)
The migration of organic contaminants in the subsurface, due to leaking underground storage tanks, includes both discrete and dissolved phase plume movements through the porous media. Such problems always involve the multiphase flow and mass transport through three phases, namely air, oil, and water. A finite element model is developed in this thesis based on the theory of multiphase flow weakly-coupled with the theory of mass transport, in a three-dimensional setting. Galerkin's method is employed to derive the finite element formulations for multiphase flow and mass transport based on the appropriate governing differential equations. The equations for multiphase flow are based on van Genuchten's model for unsaturated flow for air and water. In this model, the saturation-pressure-conductivity relations are used to obtain the constitutive behavior. The solution procedure of the resulting time dependent nonlinear equation involves using a general 0-scheme, for time integration, and a modified Picard's method, for nonlinear iteration. The governing equation for mass transport in a three-phase system is derived based on the assumption of linear partitioning between the air, oil, water, and solid phases. The equations for flow and transport are weakly-coupled through the time lagged interphase mass transfer term. A computer program called IMFTP3D is developed. The program can solve problems related to (1) multiphase immiscible flow, (2) diffusion without flow, and (3) multiphase flow weakly-coupled with mass transport. The three-dimensional model is validated for all three options based on previous two-dimensional models and laboratory experiments present in the literature. Laboratory experiments where conducted involving gasoline movements through both a one-dimensional column and a two-dimensional flume. The computer program, IMFTP3D, was then used to investigate the usefulness of the model in predicting water outflow in for the column problem and plume movements in the flume experiment. / Master of Science
8

Underground storage organs of plants as a food source for Pleistocene hunter-gatherers in the southern Cape

Singels, Elzanne 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The abundance and diversity of carbohydrate and protein resources in the southern Cape of South Africa may well have aided the survival of modern humans through the harsh climatic conditions of the late Pleistocene. Until now, the carbohydrate resources, in particular the underground storage organs (USOs) of some plant species have not been described from a forager’s perspective. This is baffling when one considers that the Cape Floristic Region of South Africa harbors the highest diversity of geophyte (herbaceous plants which possess USOs) species in the world. I report on USO distribution and abundance in the southern Cape of South Africa and on the effort, nutritional return and energetic return rates of harvesting these USOs. To determine their distribution and abundance, I assessed identity and abundance in a hundred 25m2 plots. These data, along with biomass data of every species sampled, allowed me to quantify the variation of this potential food source over different habitat types in the southern Cape landscape. Furthermore, I observed the time it took for human subjects to gather a sample of six USO species in three different vegetation types and in two seasons. Proximal analyses of the nutritional content of each of these species provided data which, when combined with foraging time, enabled a basic quantification of the return rate of energy (in calories) per time unit. There is high variability in the distribution of edible USO abundance and biomass across the study area, with some sites having very high biomass. Such biomass hotspots are likely to have been targeted by foragers, returning biomass values comparable to other studies which have been conducted on extant hunter-gatherer communities. Due to considerable variation over the landscape, the hotspots of biomass did not correlate significantly with any abiotic variables we measured. This suggests that hotspots of high biomass may have been challenging to find, unless the cognitive skills required to locate such patches were sufficiently developed – certainly excellent knowledge of the landscape and botany would have been crucial if survival depended on locating these diet items. USO species belonging to the Iridaceae family had the highest overall and average biomass in the area, so it is not surprising that this family is best represented amongst USO plant remains found in the archaeological record. Little effort (time) was required to obtain the six species of USOs we observed, although the weights obtained were also low. The nutritional returns of the six test species were higher than in other studies. The return rates per simulated foraging event in this study therefore compare favorably to the anthropological observations of extant hunter-gatherer communities. The lines of evidence presented in this thesis therefore lend support to the hypothesis that the USO resources of the southern Cape would have provided a large component of the carbohydrate requirements for sustaining hunter-gatherer communities. The data set presented in this thesis can be considered a baseline for future studies. / AFRIKAANSE OPSOMMING: Die digtheid en diversiteit van koolhidraat- en proteïenhulpbronne in die Suid-Kaap van Suid-Afrika mag die oorlewing van die moderne mens beïnvloed het tydens die ongunstige klimaatstoestande wat geheers het deur die laat Pleistoseen. Tot op hede is die koolhidraathulpbronne in die area nie beskryf vanuit ‘n kosversamelaar se perspektief af nie, spesifiek nie die koolhidrate wat deur ondergrondse stoororgane (OSO's) van sommige plantspesies verskaf kan word nie. Dié feit is verstommend as mens in ag neem dat die Kaapse Floristiese Streek van Suid-Afrika die hoogste geofietspesies (kruidagtige plante met OSO's) diversiteit ter wêreld het. Ek rapporteer oor die verspreiding en digtheid van OSO's in die Suid-Kaap en op die inspanning, voedingswaarde en energie-opbrengskoerse verbonde aan die oes van dié OSO's. Verspreiding en digtheid is bepaal oor ʼn honderd 25m2 plotte. Dié data, saam met die biomassa-data van elke spesie wat geïdentifiseer was, is gebruik om potensiële voedselbronne te kwantifiseer in verskillende habitattipes in die Suid-Kaap. Ek het verder die tyd wat dit neem vir mense om die ses geïdentifiseerde OSO-spesies te oes in drie verskillende habitatte en twee seisoene waargeneem. Voedingswaarde-data, tesame met OSO-oestyd-data, is gebruik vir die basiese berekening van energie-opbrengskoerse van spesies deur middel van proksimale analises. Daar is hoë variasie in die verspreiding, digtheid en biomassa van eetbare OSO's gevind in die studie-area, met sommige plotte wat baie hoë biomassa bevat het. Hierdie areas van hoë biomassa sou heel waarskynlik deur kos-versamelaars geteiken gewees het, en gevolglik hoë opbrengste van biomassa bied, wat vergelykbaar is met die biomassa-waardes wat waargeneem word binne areas waar huidige jagter-versamelaar-gemeenskappe tans oorleef. As gevolg van die aansienlike variasie wat waargeneem is oor die landskap het die hoë-biomassa-areas nie beduidend gekorreleer met enige abiotiese veranderlikes wat gemeet is nie. Dit dui daarop dat hoë-biomassa-areas moeilik kan wees om te vind, tensy kognitiewe vermoëns wat noodsaaklik is om kolle van hoë biomassa te vind ontwikkel was. OSO-spesies wat aan die Iridaceae-familie behoort het die hoogste algehele en gemiddelde biomassa in die area gehad. Dit is dus nie verbasend dat dié familie die beste verteenwoordig word in die argeologiese rekord van OSO-plantoorskot nie. Min inspanning (tyd) was nodig om die OSO's van die ses geïdentifiseerde spesies te bekom, alhoewel die massa wat bekom is ook laag was. Die voedingswaarde-opbrengs (per eenheidsmassa) van die ses toetsspesies was hoër as in ander studies. Die energie-opbrengskoers per versamelingsgebeurtenis het gevolglik ook gunstig vergelyk met die antropologiese waarnemings wat van huidige jagter-versamelaars gemeenskappe gemaak is. Die resultate van hierdie studie ondersteun die hipotese dat die OSO-hulpbronne in die Suid-Kaap 'n groot komponent van die koolhidraat-vereistes van jagter-versamelaar-gemeenskappe sou gewees het. Die datastel wat in dié tesis aangebied word kan as 'n basisverwysing dien vir toekomstige studies.
9

Petroleum cleanup in the United States: A historical review and comparison of state programs

Terwilliger, Timothy A 01 June 2006 (has links)
Cleanup of leaking underground storage tank (LUST) sites has been a priority for the United States of America (USA) for more than 20 years due to the large number of sites, the potential harmful health affects associated with gasoline components and the fact that single owners may not have the ability to pay for cleanup of these sites. In June 2006, the US Environmental Protection Agency (EPA) reported that of the 459,637 confirmed releases from USTs that had occurred previously, 342,688 had been remediated, which leaves 116,949 sites yet to be completed across the USA. Petroleum cleanup programs tend to be managed at the State level; however, there are wide variations among State programs in terms of information access, risk perception and funding availability. While each of the Federal and State UST programs has evolved to meet specific requirements, there has not been a comprehensive comparison of the individual State programs.In this thesis, State petroleum cleanup programs across the USA are evaluated to determine similarities and differences in an effort to identify factors that affect petroleum cleanup progress. Many parameters enter the equation in determining petroleum cleanup effectiveness. Not only are the parameters of the State program operation important, but also the characteristics of each State, including drinking water source and perceived risk associated with petroleum contamination, factor into the determination.A representative group of States and State petroleum cleanup programs were evaluated and the characteristics of States were compared to cleanup progress to determine factors affecting efficiency. Based on trend analysis the cleanup levels for toluene, ethylbenzene and total xylenes correlate directly to the cost of LUST site cleanup. For States with less perceived risk from petroleum contamination, the cleanup goals are less stringent; therefore, fewer resources and less time are required to complete site cleanup. Consequently, petroleum cleanup in States with less-stringent goals is achieved more efficiently. The knowledge of these drivers of efficient petroleum cleanup can be used to expeditiously pursue completion of the thousands of sites remaining across the USA.
10

Development of a Pre-Impact Environmental Site Characterization for the Bryan Mound, Texas Strategic Petroleum Reserve

Hernandez, Sylvia A. 12 1900 (has links)
This thesis presents a model for developing site-specific contingency plans to be used during spill response, remediation, and post-spill monitoring using the Strategic Petroleum Reserve's Bryan Mound site as a case study. Bird and vegetation observations provide baseline data for biological conditions, and sediment sampling for total petroleum hydrocarbons serves as a chemical component of the model. Results demonstrate previously unknown conditions that would hinder remediation and affect the persistence of petroleum contaminants. Results also established previously unmapped dominant bird and vegetation types likely to be impacted by a spill at the site. This model points to a reconsideration of individual facilities' responsibilities when planning for large-scale disasters and protecting the sensitive ecosystems surrounding their sites.

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