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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.
11

The organizational impact on the gas pipeline industry in South Africa

Van Tonder, Jeremiah Johannes Cornelius. January 2008 (has links)
M.Tech. Business Administration. Business School. / This research study examines processes of change management due to regulatory impact on organisations within the South African gas pipeline industry (energy industry). It concludes that a 'changing organisation' is not simply the product of good design; its existence is subject to history and to shifting power relations (i.e. Government) both within and outside of organisations.
12

Design of a clamp-on ultrasonic flow meter for wet gas pipelines

Vedapuri, Damodaran. January 2001 (has links)
Thesis (Ph. D.)--Ohio University, June, 2001. / Title from PDF t.p. Includes bibliographical references (leaves 191-193).
13

Induced currents in gas pipelines due to nearby power lines

Markovic, Dejan. January 2005 (has links)
Thesis (M.Eng.)--University of Wollongong, 2005. / Typescript. Includes bibliographical references: leaf 115-120.
14

Plug formation and dissociation of mixed gas hydrates and methane semi-clathrate hydrate stability : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemical and Process Engineering, University of Canterbury /

Hughes, Thomas John. January 2008 (has links)
Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). Includes bibliographical references (p. 204-220). Also available via the World Wide Web.
15

The analysis of pipeline leak tests using DEGADIS model

Chamorro, Alexander. January 1999 (has links)
Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains ix, 123 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 64-65).
16

Power and energy geopolitical aspects of the transnational natural gas pipelines from the Caspian Sea basin to Europe /

Benke, Ildiko. January 2010 (has links) (PDF)
Thesis (M.S. in Defense Analysis)--Naval Postgraduate School, June 2010. / Thesis Advisor(s): Tsypkin, Mikhail ; Second Reader: Lober, George. "June 2010." Description based on title screen as viewed on July 14, 2010. Author(s) subject terms: Natural gas, transportation routes, pipelines, power rivalry, energy demand, energy resources, energy policy, energy security, post-Cold war era, Caspian Sea basin, Russian periphery, geopolitical, littoral states, political instability. Includes bibliographical references (p. 53-56). Also available in print.
17

Pipeline Integrity Management System (PIMS) using Bayesian networks for lifetime extension

Sulaiman, Nurul Sa'aadah January 2017 (has links)
The majority of the world's offshore infrastructures are now showing the sign of aging and are approaching the end of their original design life. Their ability to withstand various operational and environmental changes have been the main concerns over the years. This is because the pipeline will still need to operate for a few more decades with increasing demand of oil and gas supply. To address the issues, an effective pipeline integrity management system is required to manage pipeline systems and to ensure the reliability and availability of the pipeline. The main goal is to identify, apply, and assess the applicability of the Bayesian network approach in evaluating the integrity of subsea pipelines that evolves with time. The study is aimed to specifically handle knowledge uncertainties and assist in the decision making of subsea pipeline integrity assessment. A static Bayesian network model was developed to compute the probability of pipeline condition and investigate the underlying factors that lead to pipeline damage. From the model, the most influential factors were identified and the sensitivity analysis demonstrated that the developed model was robust and accurate. The proposed model was then extended to develop a decision tool model using an Influence Diagram. The results from the proposed influence diagram were used to prioritize the maintenance scheme of the pipeline segments. Benefit to cost ratio was applied to determine the pipeline maintenance intervals. Dynamic Bayesian network was utilized to model timedependent deterioration of pipeline structural reliability. A good agreement with conventional structural reliability method is achieved. The present thesis has demonstrated the applicability and effectiveness of Bayesian network approach in the field of oil and gas. It is hoped that the proposed models can be applied by oil and gas pipeline practitioners to enhance the integrity and lifeltime of the oil and gas pipeline.
18

Optimising the renewal of natural gas reticulation pipes using GIS

Hobson, Alan George Cawood 04 1900 (has links)
Thesis (MA)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: A major concern for Energex, Australia's largest energy utility in South East Queensland, is the escape of natural gas out of their reticulation systems. Within many of the older areas in Brisbane, these networks operate primarily at low and medium pressure with a significant percentage of mains being cast iron or steel. Over many years pipes in these networks have been replaced, yet reports show that unaccounted for gas from the same networks remain high. Furthermore, operation and maintenance budgets for these networks are high with many of these pipes close to the end of their economic life. When operation and maintenance costs exceed the costs of replacement, the Energex gas utility initiates projects to renew reticulation networks with polyethylene pipes. Making decisions about pipe renewal requires an evaluation of historical records from a number of sources, namely: • gas consumption figures, • history of leaks, • maintenance and other related cost, and • the loss of revenue contributed by unaccounted for gas. Financial justification of capital expenditure has always been a requirement for renewal projects at the Energex gas utility, however the impact of a deregulation in the energy utility market has necessitated a review of their financial assessment for capital projects. The Energex gas utility has developed an application that evaluates the financial viability of renewal projects. This research will demonstrate the role of GIS integration with the Energex financial application. The results of this study showed that a GIS integrated renewal planning approach incorporates significant benefits including: • Efficient selection of a sub-network based on pipe connectivity, • Discovery of hidden relationships between spatially enabled alphanumeric data and environmental information that improves decision making, and • Enhanced testing of proposed renewal design options by scrutinizing the attributes of spatial data. / AFRIKAANSE OPSOMMING: 'n Groot bron van kommer vir Energex, Australië se grootste energieverskaffer in Suidoos- Queensland, is die verlies van natuurlike gas uit hul gasdistribusie netwerke. In 'n groot deel van ouer Brisbane opereer hierdie netwerke hoofsaaklik teen lae en medium druk, met 'n aansienlike persentasie van hoofpyplyne wat uit gietyster of staal bestaan. Al is sommige pyplyne in hierdie netwerke met verloop van tyd vervang, maak verslae dit duidelik dat 'n groot deel van die gas in hierdie netwerke steeds langs die pad verlore gaan. Die operasionele - en onderhoudsbegrotings vir hierdie netwerke is boonop hoog, met 'n groot persentasie van die pyplyne wat binnekort aan die einde van hulle ekonomiese leeftyd kom. Wanneer operasionele- en onderhoudsonkostes die koste van vervanging oorskry, beplan Energex se gasvoorsienings-afdeling projekte om verspreidingsnetwerke te hernu met poli-etileen pype. Om sinvolle besluite te neem tydens pyplynhernuwings, word verskeie historiese verslae geraadpleeg, insluitend: gasverbruikvlakke, lekplek geskiedenis rekords, onderhoud- en ander verwante onkostes, asook die verlies van inkomste weens verlore gas. Alhoewel finansiële stawing van kapitale uitgawes nog altyd 'n voorvereiste was tydens hernuwingsprojekte by Energex, het die impak van privatisering op die energieverskaffingsmark dit noodsaaklik gemaak om hulle finansiële goedkeuringsproses vir kapitaalprojekte te hersien. Energex het dus 'n sagteware toepassing ontwikkel wat die finansiële gangbaarheid van hernuwingsprojekte evalueer. Hierdie navorsing sal die moontlike integrasie van geografiese inligtingstelsels (GIS) met dié van Energex se finansiële evalueringspakket demonstreer. Die resultate van hierdie studie toon dat die integrasie van GIS in die hernuwingsproses aansienlike voordele inhou, insluitende: • die effektiewe seleksie van sub-netwerke, gebaseer op pyp konnektiwiteit, • die ontdekking van verskuilde verwantskappe tussen geografies-ruimtelike alfanumeriese data en omgewingsinligting, wat besluitneming vergemaklik, en • verbeterde toetsing van voorgestelde hernuwingsopsies deur die indiepte-nagaan van geografiesruimtelike elemente.
19

Development of instrumentation for acoustic monitoring

Mehra, Deepak. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains x, 61 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 59-61).
20

Effects of polymerization conditions and imidization methods on performance of crosslinkable polymer membrane for CO₂/CH₄ separation

Kim, Danny Jinsoo 16 September 2013 (has links)
Natural gas feeds often contain contaminants such as CO₂, H₂S, H₂O, and small hydrocarbons. Carbon dioxide is a major contaminant reducing the heating value of the gas and causing pipeline corrosion, so CO₂ level should be lowered to below 2% to meet the United States pipeline specifications. Membrane separation technology can be advantageous over cryogenic distillation and amine adsorption in terms of cost and efficiency. The key hurdle to overcome in polymeric membrane separation technology is improvement in selectivity, productivity, and durability without introducing significant additional cost. The ultimate goal of this study is to analyze effects due to polymerization conditions and imidization methods on properties of 1,3-propanediol monoesterified crosslinkable polyimide (PDMC). Hillock, Omole, Ward, and Ma did work on PDMC synthesis; however, variability of polymer properties remains a challenge that must be overcome for industrial implementation of PDMC material. First, reaction temperature and reaction time of polymerization prior to imidization were considered as key conditions to affect molecular weight, crosslinkability and transport properties of polymer. Batches with controlled reaction temperature and time were prepared, and properties of each dense film were measured and optimized in terms of permeability, selectivity, and plasticization suppression. Second, imidization methods for PDMC were also studied. There are mainly two kinds of Imidization: chemical Imidization and thermal Imidization. Surprisingly, thermally imidized PDMC showed 70% higher permeability than chemically imidized samples with minimal acrifice in selectivity. At high reaction temperature during the thermal imidization, transamidation can occur. It is believed that the transamidation led to more randomized sequence distribution in the thermally imidized samples. We thus hypothesize that the higher permeability of the thermally imidized PDMC results from greater uniformity of the sequence distribution, as compared to the chemically imidized sample that does not experience high temperature during imidization. XRD, DSC, DMA, and permeation instruments checked and supported this hypothesis. FTIR, TGA, and NMR ruled out the possibility of an alternate hypothesis related to side reaction. Finally, effects of aggressive feed conditions on both chemically imidized PDMC and thermally imidized PDMC dense film were examined. The aggressive feed conditions include high CO₂ partial pressure, operating temperatures, and exposure to high feed pressure. Testing aggressive feed conditions for dense film should be pursued before pursuing hollow fiber applications, to decouple effects on the basic material from those on the more complex asymmetric morphology. This study enables understanding of the disparity between various previous researchers’ selectivity and permeability values. The work shows clearly that polymerization conditions and imidization methods must be specified and controlled to achieve consistently desirable polymer properties. In addition, for batch scale-up and development to a hollow fiber, this fundamental study should enable production of high molecular weight PDMC with good fiber spinnability and defect-free structure.

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