Δημοσιεύσεις σε Συνέδρια
Μόνιμο URI για αυτήν τη συλλογήhttps://dspace.library.tuc.gr/handle/123456789/126
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Πλοήγηση Δημοσιεύσεις σε Συνέδρια ανά Συγγραφέα "Παπαμιχαηλ Ιωαννης"
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Δημοσίευση A feedback-based approach for mainstream traffic flow control of multiple bottlenecks on motorways(International Federation of Automatic Control, 2014) Iordanidou Georgia-Roumpini; Ιορδανιδου Γεωργια-Ρουμπινη; Papamichail Ioannis; Παπαμιχαηλ Ιωαννης; Roncoli Claudio; Papageorgiou Markos; Παπαγεωργιου ΜαρκοςMainstream traffic flow control (MTFC) enabled via variable speed limits (VSLs) has been investigated in previous studies, utilizing various control strategies. In this paper a new feedback control strategy is proposed for MTFC enabled via VSLs, considering multiple bottleneck locations. Results are evaluated using a validated macroscopic model. The feedback concept is robust and can be immediately implemented in the field as it considers practical and safety constraints.Δημοσίευση Local ramp metering with distant downstream bottlenecks: a comparative study(Institute of Electrical and Electronics Engineers, 2014) Wang Yibing; Kan Yuheng; Papageorgiou Markos; Παπαγεωργιου Μαρκος; Papamichail Ioannis; Παπαμιχαηλ ΙωαννηςThe well-known feedback ramp metering algorithm ALINEA can be applied for local ramp metering or included as a key component in a coordinated ramp metering system. ALINEA uses real-time occupancy measurements from the ramp flow merging area that may be at most few hundred meters downstream of the metered on-ramp nose. In many practical cases, however, bottlenecks with smaller capacity than the merging area may exist further downstream for various reasons, which suggests using measurements from those further downstream bottlenecks. Recent theoretical and simulation studies indicate that ALINEA may lead to a poorly damped closed-loop behavior in this case, but PI-ALINEA, a suitable Proportional-Integral (PI) extension of ALINEA, can lead to satisfactory control performance. This paper addresses the same local ramp-metering problem in the presence of downstream bottlenecks, with a particular focus on the general capacity of PI-ALINEA with three distinct types of bottleneck that may often be encountered in practice, i.e. (1) an uphill case; (2) a lane-drop case; (3) an un-controlled on-ramp case. Extensive simulation studies are conducted using a macroscopic traffic flow model to demonstrate that the performance of ALINEA indeed deteriorates in each of these bottleneck cases, while significant improvement is obtained using PI-ALINEA in all cases. Moreover, with its control parameters appropriately tuned beforehand, PI-ALINEA is found to be universally applicable, with little fine-tuning required for field applications.Δημοσίευση Model predictive control for multi-lane motorways in presence of VACS(Institute of Electrical and Electronics Engineers, 2014) Roncoli Claudio; Roncoli Claudio; Papamichail Ioannis; Παπαμιχαηλ Ιωαννης; Papageorgiou Markos; Παπαγεωργιου ΜαρκοςA widespread use of vehicle automation and communication systems (VACS) is expected in the next years. This may lead to improvements in traffic management because of the augmented possibilities of using VACS both as sensors and as actuators. To achieve this, appropriate studies, developing potential control strategies to exploit the VACS availability, are essential. This paper describes a model predictive control framework that can be used for the integrated and coordinated control of a motorway system, considering that vehicles are equipped with specific VACS. Microscopic simulation testing demonstrates the effectiveness and the computational feasibility of the proposed approach.Δημοσίευση Motorway flow optimization in presence of vehicle automation and communication systems(National Technical University of Athens, 2014) Roncoli Claudio; Papamichail Ioannis; Παπαμιχαηλ Ιωαννης; Papageorgiou Markos; Παπαγεωργιου ΜαρκοςThis paper describes a novel approach for defining optimal strategies in motorway traffic flow control, considering that a portion of vehicles are equipped with vehicle automation and communication systems. An optimisation problem, formulated as a Quadratic Programming (QP) problem, is developed with the purpose of minimising traffic congestion. The proposed problem is based on a first-order macroscopic traffic flow model able to capture the lane changing and the capacity drop phenomena. An application example demonstrates the achievable improvements in terms of the Total Time Spent if the vehicles travelling on the motorway are influenced by the control actions computed as a solution of the optimisation problem.Δημοσίευση Optimal control for multi-lane motorways in presence of Vehicle Automation and Communication Systems(International Federation of Automatic Control, 2014) Roncoli Claudio; Papageorgiou Markos; Παπαγεωργιου Μαρκος; Papamichail Ioannis; Παπαμιχαηλ ΙωαννηςThe presence and exploitation of Vehicle Automation and Communication Systems (VACS) while defining optimal control strategies in motorway traffic flow control is addressed in this paper. VACS are supposed to act both as sensors (providing information on traffic conditions) and as actuators, allowing the application of ramp metering, variable speed limit control, and lane changing control. A quadratic programming problem is defined on the basis of a novel first-order traffic flow model for multi-lane motorways. An example is presented in order to illustrate the effectiveness of the proposed optimisation problem.Δημοσίευση An optimisation-oriented first-order multi-lane model for motorway traffic(Transportation Research Board, 2015) Roncoli Claudio; Roncoli Claudio; Papageorgiou Markos; Παπαγεωργιου Μαρκος; Papamichail Ioannis; Παπαμιχαηλ ΙωαννηςEmerging vehicle automation and communication systems (VACS) may contribute to the mitigation of motorway traffic congestion on the basis of appropriate traffic control strategies. Based on appropriate VACS-based actuators, future traffic control may incorporate vehicle speed control and lane-assignment or lane-changing recommendations. To this end, an appropriate traffic flow model is needed, both for control strategy design and as a no-control base case for comparative evaluation studies. In this context, this paper presents a novel first-order multi-lane macroscopic traffic flow model for motorways which is mainly intended for use within a related optimal control problem formulation. The starting point is close to the well-known cell-transmission model (CTM), which is modified and extended to consider additional aspects of the traffic dynamics, such as lane changing and the capacity drop. The model has been derived with a view to combine realistic traffic flow description with a simple (piecewise linear) mathematical form, which can be exploited for efficient optimal control problem formulations. Although the model has been primarily derived for use in future traffic conditions including VACS, it may also be used for conventional traffic flow representation. In fact, the accuracy of the proposed modelling approach is demonstrated through calibration and validation procedures using conventional real data from an urban motorway located in Melbourne, Australia.