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dc.contributor.authorJun, Hwandonen_US
dc.date.accessioned2014-03-14T20:12:32Z
dc.date.available2014-03-14T20:12:32Z
dc.date.issued2005-05-06en_US
dc.identifier.otheretd-05242005-212555en_US
dc.identifier.urihttp://hdl.handle.net/10919/27875
dc.description.abstractValves play a critical role in a water distribution system for subsystem isolation and flow or pressure control. Among them, subsystem isolation is required to repair or to rehabilitate a broken component and can be done by closing adjacent valves. To evaluate the role of valves, the concept of â Segmentâ is necessary. A segment consists of a set of pipes and nodes isolated together by closing adjacent valves when a pipe fails. An efficient algorithm to identify segments in a water distribution system is proposed. In addition, when a segment is isolated, an additional subsystem may be disconnected from water sources by the segment isolation. It is a topological unintended isolation. In addition, a hydraulic failure, in terms of pressure types of failures at demand nodes should be considered. These three account for the failure impact of a pipe. Placing valves efficiently improves the reliability of a water distribution system. However, the valve reliability itself is not 100%. Therefore, valve failure consequence should be explored in determining the locations of valves. For this purpose, three methodologies, namely segment-valve matrix algorithm, decision tree approach and simulation are proposed. Another consideration for placing valves is a strategic valving rule, namely N and (N-1) valving rules. Using a formulation for node reliability in terms of failing valves, the reliability difference between the two valving rules is evaluated. We also employ a mixed N and (N-1) valving rule. Another strategic valving rule, a segment size reducing approach minimizing the number of affected customers is proposed. The developed algorithms are utilized to build software, the Strategic Valve Management Model, to solve practical problems. The methodology is applied to three real water distribution systems.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartDiss_HwandonJun.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectSegmenten_US
dc.subjectPerformance Indicatorsen_US
dc.subjectFailure Analysisen_US
dc.subjectSimulationen_US
dc.subjectMatrix Algorithmen_US
dc.subjectValveen_US
dc.subjectWater Distribution Systemen_US
dc.titleStrategic valve locations in a water distribution systemen_US
dc.typeDissertationen_US
dc.contributor.departmentCivil Engineeringen_US
dc.description.degreePh. D.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineCivil Engineeringen_US
dc.contributor.committeechairLoganathan, G. V.en_US
dc.contributor.committeememberTrani, Antonio A.en_US
dc.contributor.committeememberLohani, Vinod K.en_US
dc.contributor.committeememberYounos, Tamimen_US
dc.contributor.committeememberKibler, David F.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-05242005-212555/en_US
dc.date.sdate2005-05-24en_US
dc.date.rdate2008-06-22
dc.date.adate2005-06-22en_US


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