This paper presents the possibilities of job optimization in waterway with multiple locks and canals, in order to increase the system productivity. Safe navigation in such complex waterway system is very demanding. So...This paper presents the possibilities of job optimization in waterway with multiple locks and canals, in order to increase the system productivity. Safe navigation in such complex waterway system is very demanding. Some of the problems that need to be solved are： How to control traffic in a way that vessels move in opposite directions; How to resolve possible conflicts in case that more vessels try to acquire particular lock at the same time; How to avoid possible deadlocks; How to ensure the vessel passage in the shortest possible time？ It is necessary to apply adequate control policy to avoid deadlocks and blocks the vessels＇ moving only in the case of dangerous situation. The motion of vessels can be described as the set of discrete events and states. Herein we propose deadlock avoidance algorithm for complex waterway system with multiple key resources and we use multiple re-entrant flowlines class of Petri net （MRF^PN）. The solution represents deadlock prevention supervisor in a sense that vessels are stopped only in a case of immediate dangerous situation in dense traffic. The goal of this paper is to find optimal, conflict and deadlock free job schedule in CWS. In this sense, the authors developed the algorithm which integrates MRF^PN with a genetic algorithm. The algorithm deals with multi-constrained scheduling problem with shared resources. The final goals are minimization the total travel time of vessels through the waterway system.展开更多
The distant downstream proportional integral(PI) feedback control was applied to the W-M lateral canal of the Maricopa Stanfield Irrigation and Drainage District located in central Arizona,U.S.A.Proper configuration o...The distant downstream proportional integral(PI) feedback control was applied to the W-M lateral canal of the Maricopa Stanfield Irrigation and Drainage District located in central Arizona,U.S.A.Proper configuration of those controls for the ca-nal can be challenging.Towards this end,an integrated approach to the design of an automatic control system for the canal was proposed.This approach presented herein is not only a systematical review of previous work,but also represents a further ad-vance of the previous simulation study by Tsinghua University(Shang et al,2011) on relating the canal control algorithm to local PI controls for the real canal.To evaluate the control system potential,performance of the control algorithm that was ob-tained through implanting predicative module into linear quadratic regulator(LQR) was analyzed with singular value bode.Additional "manufactured" tests were conducted to compare with the control system that is currently in use.The results indi-cated that the developed control system rather than the system in current use had considerable potential to closely match dis-charge at the downstream check structures with those ordered by water users while maintaining the water level throughout the length of the canal.展开更多
文摘This paper presents the possibilities of job optimization in waterway with multiple locks and canals, in order to increase the system productivity. Safe navigation in such complex waterway system is very demanding. Some of the problems that need to be solved are： How to control traffic in a way that vessels move in opposite directions; How to resolve possible conflicts in case that more vessels try to acquire particular lock at the same time; How to avoid possible deadlocks; How to ensure the vessel passage in the shortest possible time？ It is necessary to apply adequate control policy to avoid deadlocks and blocks the vessels＇ moving only in the case of dangerous situation. The motion of vessels can be described as the set of discrete events and states. Herein we propose deadlock avoidance algorithm for complex waterway system with multiple key resources and we use multiple re-entrant flowlines class of Petri net （MRF^PN）. The solution represents deadlock prevention supervisor in a sense that vessels are stopped only in a case of immediate dangerous situation in dense traffic. The goal of this paper is to find optimal, conflict and deadlock free job schedule in CWS. In this sense, the authors developed the algorithm which integrates MRF^PN with a genetic algorithm. The algorithm deals with multi-constrained scheduling problem with shared resources. The final goals are minimization the total travel time of vessels through the waterway system.
基金supported by the National Natural Science Foundation of China(Grant Nos.51109112,51109079)the Open Research Fund of State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin (Grant No.IWHR-SKL-201117)+1 种基金the China Postdoctoral Science Foundation(Grant No.20110490412)the China Scholarship Council is acknowledged for the financial support
文摘The distant downstream proportional integral(PI) feedback control was applied to the W-M lateral canal of the Maricopa Stanfield Irrigation and Drainage District located in central Arizona,U.S.A.Proper configuration of those controls for the ca-nal can be challenging.Towards this end,an integrated approach to the design of an automatic control system for the canal was proposed.This approach presented herein is not only a systematical review of previous work,but also represents a further ad-vance of the previous simulation study by Tsinghua University(Shang et al,2011) on relating the canal control algorithm to local PI controls for the real canal.To evaluate the control system potential,performance of the control algorithm that was ob-tained through implanting predicative module into linear quadratic regulator(LQR) was analyzed with singular value bode.Additional "manufactured" tests were conducted to compare with the control system that is currently in use.The results indi-cated that the developed control system rather than the system in current use had considerable potential to closely match dis-charge at the downstream check structures with those ordered by water users while maintaining the water level throughout the length of the canal.
