The Experts below are selected from a list of 246 Experts worldwide ranked by ideXlab platform
C.r. Miska - One of the best experts on this subject based on the ideXlab platform.
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worcester solenoid actuated gas operated mco Isolation Valves
Other Information: PBD: 13 Nov 2000, 2000Co-Authors: C.r. MiskaAbstract:These Valves are 1 inch gas-operated full-port ball Valves incorporating a solenoid and limit switches as integral parts of the actuator that are used in process streams within the CWF hood. The Valves fail closed (on loss of pressure or electrical) to prevent MCO vent drain to either reduce air In-leakage or loss of He. The Valves have couplings for transverse actuator mounting.
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SCHe Helium Bottles and Associated Isolation Valves
2000Co-Authors: C.r. MiskaAbstract:No abstract prepared
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worcester solenoid actuated gas operated mco Isolation Valves
Other Information: PBD: 3 Sep 2000, 2000Co-Authors: C.r. MiskaAbstract:These Valves are 1 inch gas-operated full-port ball Valves incorporating a solenoid and limit switches as integral parts of the actuator that are used in different process streams within the CVDF hood. The Valves fail closed (on loss of pressure or electrical) for MCO Isolation to either reduce air in leakage or loss of He. All Valves have coupling for transverse actuator mounting.
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whitey sche ball Valves provide test port Isolation
Other Information: PBD: 15 Sep 2000, 2000Co-Authors: C.r. MiskaAbstract:These Valves are 1/4 inch ball Valves fabricated of 316 stainless steel. Packing is TFE (standard). They are used as normally closed Isolation Valves for test ports in the SCHe System between the gage root valve and the pressure indicator.
Carl Van Katwijk - One of the best experts on this subject based on the ideXlab platform.
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Worchester solenoid - actuated gas-operated MCO Isolation Valves
1999Co-Authors: Carl Van KatwijkAbstract:Solenoid-actuated gas-operated MCO Isolation Valves CGI-SNF-D-07-P4-001
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Worchester solenoid - actuated gas-operated MCO Isolation Valves
1999Co-Authors: Carl Van KatwijkAbstract:Worcester Solenoid -- actuated gas-operated MCO Isolation Valves CGI-SNF-D-46-1-P4-015
Stefano Alvisi - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Segment identification in water distribution systems
2020Co-Authors: Stefano Alvisi, Enrico Creaco, Marco FranchiniAbstract:This paper presents a new method for identifying the segments that are formed after the installation and closure of Isolation Valves in a water distribution network. This method is able to identify segments also when one-way devices are installed in the network. Thanks to its short computing times, the method enables the analysis of real networks which always comprise a large number of nodes and pipes. The numerical examples presented in this paper refer to two real water distribution networks. The first network is a part of a provincial network where two one-way devices are present; the second is a complex urban network without one-way devices. The method was first used to analyse the existing situation in both networks, i.e. the set of segments that are formed as a consequence of the present valve system. The method was subsequently used for the problem of the hypothetic redesign of the Isolation valve system in the second urban network, i.e. the search for the optimal positions of the Isolation Valves in the network; in the redesign phase it provided solutions which are more cost-effective than the configuration of Isolation Valves currently present, the level of water service reliability being the same.
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a heuristic procedure for the automatic creation of district metered areas in water distribution systems
Urban Water Journal, 2014Co-Authors: Stefano Alvisi, Marco FranchiniAbstract:This paper presents a procedure for the automatic creation of district metered areas (DMAs) in a water distribution system. The procedure uses techniques derived from graph theory (Breadth First Search and algorithm for finding the shortest paths in a graph) and demand-driven hydraulic simulations of the network in order to (a) divide the nodes among an assigned number of DMAs, (b) identify the ‘open’ links between districts where flow meters will be placed and (c) identify the ‘closed’ links between districts where Isolation Valves will be placed. The application of the proposed procedure to the case of a real water distribution system revealed it to be robust and effective. In particular, the results obtained show that the procedure makes it possible to identify very good solutions in terms of resilience and minimum pressures when reference to the peak demand and fire-flow conditions is made. The resulting performance indicators were better than those obtainable by applying a similar procedure previousl...
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Segment identification in water distribution systems
Urban Water Journal, 2011Co-Authors: Stefano Alvisi, Enrico Creaco, Marco FranchiniAbstract:This paper presents a new method for identifying the segments that are formed after the installation and closure of Isolation Valves in a water distribution network. This method is able to identify segments also when one-way devices are installed in the network. Thanks to its short computing times, the method enables the analysis of real networks which always comprise a large number of nodes and pipes. The numerical examples presented in this paper refer to two real water distribution networks. The first network is a part of a provincial network where two one-way devices are present; the second is a complex urban network without one-way devices. The method was first used to analyse the existing situation in both networks, i.e. the set of segments that are formed as a consequence of the present valve system. The method was subsequently used for the problem of the hypothetic redesign of the Isolation valve system in the second urban network, i.e. the search for the optimal positions of the Isolation Valves...
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Optimal Placement of Isolation Valves in Water Distribution Systems Based on Valve Cost and Weighted Average Demand Shortfall
Water Resources Management, 2010Co-Authors: Enrico Creaco, Marco Franchini, Stefano AlvisiAbstract:In this paper a method for optimal placement of Isolation Valves in water distribution systems is presented. These Valves serve to isolate parts of the network (segments) containing one or more pipes on which maintenance work can be performed without disrupting service in the entire network or in large portions of it. The segments formed after the installation and closure of Isolation Valves are identified and characterised using an algorithm which is based on the use of topological matrixes associated with the structure of the original network and the one modified to take account of the presence of (closed) Valves. A multi-objective genetic algorithm is used instead to search for the optimal position of the Valves. In the application of the method different objective functions were used and compared to solve the problem as to the optimal placement of the Valves. The results showed that the most appropriate ones are the total cost of the Valves (to be minimised) and the weighted average “water demand shortfall” (likewise to be minimised); in particular, the weighted average shortfall is calculated considering the shortfalls associated with the various segments of the network (shortfall is the unsupplied demand after isolating a segment) and the likelihood of failures tied to mechanical factors occurring in the segments. The methodology was applied to a case study focusing on a simplified layout of the water distribution system of the city of Ferrara (Italy).
Enrico Creaco - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Segment identification in water distribution systems
2020Co-Authors: Stefano Alvisi, Enrico Creaco, Marco FranchiniAbstract:This paper presents a new method for identifying the segments that are formed after the installation and closure of Isolation Valves in a water distribution network. This method is able to identify segments also when one-way devices are installed in the network. Thanks to its short computing times, the method enables the analysis of real networks which always comprise a large number of nodes and pipes. The numerical examples presented in this paper refer to two real water distribution networks. The first network is a part of a provincial network where two one-way devices are present; the second is a complex urban network without one-way devices. The method was first used to analyse the existing situation in both networks, i.e. the set of segments that are formed as a consequence of the present valve system. The method was subsequently used for the problem of the hypothetic redesign of the Isolation valve system in the second urban network, i.e. the search for the optimal positions of the Isolation Valves in the network; in the redesign phase it provided solutions which are more cost-effective than the configuration of Isolation Valves currently present, the level of water service reliability being the same.
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Dual topology for partitioning of water distribution networks considering actual valve locations
Urban Water Journal, 2019Co-Authors: Giovanni Francesco Santonastaso, A. Di Nardo, Enrico CreacoAbstract:ABSTRACTThis paper proposes a general framework to adjust water distribution network (WDN) partitioning algorithms to account for the real positions of Isolation Valves. It is based on changing the...
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Segment identification in water distribution systems
Urban Water Journal, 2011Co-Authors: Stefano Alvisi, Enrico Creaco, Marco FranchiniAbstract:This paper presents a new method for identifying the segments that are formed after the installation and closure of Isolation Valves in a water distribution network. This method is able to identify segments also when one-way devices are installed in the network. Thanks to its short computing times, the method enables the analysis of real networks which always comprise a large number of nodes and pipes. The numerical examples presented in this paper refer to two real water distribution networks. The first network is a part of a provincial network where two one-way devices are present; the second is a complex urban network without one-way devices. The method was first used to analyse the existing situation in both networks, i.e. the set of segments that are formed as a consequence of the present valve system. The method was subsequently used for the problem of the hypothetic redesign of the Isolation valve system in the second urban network, i.e. the search for the optimal positions of the Isolation Valves...
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Optimal Placement of Isolation Valves in Water Distribution Systems Based on Valve Cost and Weighted Average Demand Shortfall
Water Resources Management, 2010Co-Authors: Enrico Creaco, Marco Franchini, Stefano AlvisiAbstract:In this paper a method for optimal placement of Isolation Valves in water distribution systems is presented. These Valves serve to isolate parts of the network (segments) containing one or more pipes on which maintenance work can be performed without disrupting service in the entire network or in large portions of it. The segments formed after the installation and closure of Isolation Valves are identified and characterised using an algorithm which is based on the use of topological matrixes associated with the structure of the original network and the one modified to take account of the presence of (closed) Valves. A multi-objective genetic algorithm is used instead to search for the optimal position of the Valves. In the application of the method different objective functions were used and compared to solve the problem as to the optimal placement of the Valves. The results showed that the most appropriate ones are the total cost of the Valves (to be minimised) and the weighted average “water demand shortfall” (likewise to be minimised); in particular, the weighted average shortfall is calculated considering the shortfalls associated with the various segments of the network (shortfall is the unsupplied demand after isolating a segment) and the likelihood of failures tied to mechanical factors occurring in the segments. The methodology was applied to a case study focusing on a simplified layout of the water distribution system of the city of Ferrara (Italy).
Andrea Peano - One of the best experts on this subject based on the ideXlab platform.
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an asp approach for the optimal placement of the Isolation Valves in a water distribution system
DC@AI*IA, 2012Co-Authors: Andrea Peano, Marco GavanelliAbstract:Several design issues of Water Distribution Systems can be represented as combinatorial optimization problems, and then addressed by means of opportune techniques and technologies available in Computational Logic and Operational Research. My Ph.D. Thesis relates to achieve (near-)optimal solutions to such real-life problems either by exploiting potentialities of existing techniques and by developing ad hoc algorithms. Among all the design issues above mentioned, the Isolation Valve Location Problem is defined as the problem of computing the optimal placement, on the hydraulic network, of a limited number of Isolation Valves, so that any pipe can be isolable in case of failure and the maximum service disruption (varying the broken pipe) is minimized. About Computational Logic, dierent Answer Set Programming encodings to such a problem have been developed during the first stage of my research activity, and more suitable encodings are currently under study.
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an asp approach for the optimal placement of the Isolation Valves in a water distribution system
International Conference on Logic Programming, 2012Co-Authors: Andrea PeanoAbstract:My Ph.D. Thesis relates to real-life optimization problems in the hydraulic engineering field. More precisely, with the collaboration of computer scientists, operational researchers and hydraulic engineers, I investigate and exploit potentialities of various Operational Research and Artificial Intelligence techniques in order to achieve good (and, whenever possible, optimal) solutions for those particular design issues of the urban hydraulic network that can be effectively modelled as known combinatorial optimization problems. Furthermore, suchdesign issues often require to devise new specialized variants of the known combinatorial optimization problems.
