... Candidato Lorenzo Meschini Coordinatore Tutore Prof. Giuseppe Romolo Corazza Prof. Natale Pap... more ... Candidato Lorenzo Meschini Coordinatore Tutore Prof. Giuseppe Romolo Corazza Prof. Natale Papola Page 2. 2 ... 66 CAPITOLO 5 Modelli di equilibrio dinamico 69 5.1 Caricamento dinamico della rete 69 5.2 Mappa di carico della rete 70 5.3 Mappa di carico della rete Probit 70 ...
... Giuseppe Cantisani, Sapienza Università di Roma, Italy, giuseppe.cantisani@uniroma1.it Michel... more ... Giuseppe Cantisani, Sapienza Università di Roma, Italy, giuseppe.cantisani@uniroma1.it Michele Di Vito, Sapienza Università di Roma, Italy, michele ... elements (Dell'Acqua et al., 2007), altimetry (Gibreel et al., 2001), transversal characteristic of the road platform (Medina et al. ...
ABSTRACT OPTIMA is an innovative ITS (Intelligent Transport Systems) platform for traf-fic monito... more ABSTRACT OPTIMA is an innovative ITS (Intelligent Transport Systems) platform for traf-fic monitoring and management, that provides off-line estimates and real-time fore-casts concerning the use (vehicle flows) and the performances (travel times) of the road networks. To this end, OPTIMA exploits an advanced methodology for modelling transport demand and vehicle congestion, through which the behaviour of drivers and the propagation of queues are explicitly represented. The connection to actual conditions is guarantied by field measures at discrete points (loop detectors, speed radars, video cameras, probe vehicles) that are collected in real-time and sent to a control room, where sophisticated algorithms allow to reconstruct the current and future traffic pat-tern on the entire network, hence extending the available data in time and space to achieve a useful information for driver navigation and transport optimization.
... Dipartimento di Idraulica Trasporti e Strade - Università degli Studi di Roma “La Sapienza” V... more ... Dipartimento di Idraulica Trasporti e Strade - Università degli Studi di Roma “La Sapienza” Via Eudossiana 18, 00184 Roma [guido.gentile, lorenzo.meschini]@uniroma1.it °PTV – Planung ... 24. Mahut M., Florian M., Tremblay N., Campbell M., Patman D., Krnic McDaniel. ...
The objective of this paper is to present the application of a within-day Dynamic Traffic Assignm... more The objective of this paper is to present the application of a within-day Dynamic Traffic Assignment (DTA) Model to simulate ordinary, evacuation and emergency scenarios for downtown Vancouver during the forthcoming Winter Olympic Games. Within this context, the main problem was to simulate different kinds of pedestrians and vehicles-pedestrians interactions; these congestion phenomena can occur in presence of the unusual demand produced by important public events, such as sport games, music concerts and political rallies, when significant levels of pedestrian and vehicle flows are concentrated in space and time, i.e. converge to or diverge from one point/area in a relatively short time interval. Additionally, other phenomena that needed to be addressed where: - pedestrian route choice, since several routes are available to reach and leave event locations; - special event temporal demand, with time peaks concentrated around begin and end of events; - pedestrian capacity constraints, due to the limited capacity of road and sidewalks; - short term closure of streets, due to Olympic security measures. In order to address the above modeling needs, different approaches where considered, from classical static assignment, to meso simulation, to micro simulation applied to pedestrians and vehicles. Finally, a Macroscopic Dynamic Assignment model calculating Dynamic User Equilibrium was adopted, suitably extended in order to represent pedestrian flows and vehicle-pedestrian interactions.
Cerca percorso dinamico per reti di trasporto collettivo e spostamenti intermodali, che fornisce ... more Cerca percorso dinamico per reti di trasporto collettivo e spostamenti intermodali, che fornisce strategie ottimali per servizi a frequenza e ad orario considerando i ritardi alle fermate in tempo reale; registrato presso la SIAE in data 14.11.2011 con il n. 820
Cruscotto della mobilità accessibile via internet che calcola e presenta, anche su mappa, una ser... more Cruscotto della mobilità accessibile via internet che calcola e presenta, anche su mappa, una serie di indicatori per monitorare l’andamento e l’impatto del trasporto urbano, basati su misure di traffico ed emissioni con diverse aggregazioni spaziali e temporal
Assegnazione dinamica alle reti di trasporto collettivo con linee sia ad orario che a frequenza, ... more Assegnazione dinamica alle reti di trasporto collettivo con linee sia ad orario che a frequenza, in grado di simulare vincoli di capacità e fenomeni di congestione a bordo e alle fermat
Per sviluppare il Piano degli Spostamenti Casa – Lavoro relativo ai dipendenti di aziende medio-g... more Per sviluppare il Piano degli Spostamenti Casa – Lavoro relativo ai dipendenti di aziende medio-grandi; sulla base di questionari compilati via web, consente di simulare politiche di mobilità sostenibile mediante modelli di scelta modale; registrato presso la SIAE in data 14.11.2011 con il n. 821
In a recent paper [Bellei, Gentile and Papola, 2002] we have proposed a new continuous implicit p... more In a recent paper [Bellei, Gentile and Papola, 2002] we have proposed a new continuous implicit path formulation of Dynamic Traffic Assignment (D TA), where a user equilibrium is expressed as a fixed point problem in terms of arc flow temporal profiles. There, it is shown that, by extending to the dynamic case the concept of Network Loading Map, is no more needed to introduce the Continuous Dynamic Network Loading [see for instance Xu
ABSTRACT Sommario UrbIS (Urban Information System) è un Sistema Informativo Territoriale per la g... more ABSTRACT Sommario UrbIS (Urban Information System) è un Sistema Informativo Territoriale per la gestione partecipata degli ambienti urbani. Urbis consente infatti ai cittadini e/o agli operatori municipali di segnalare all'Amministrazioni Pubblica o più in generale ai gestori dei servizi, in maniera semplice ed immediata, la presenza sul territorio di specifici problemi relativi a tematiche quali: la manutenzione delle strade e dell'arredo cittadino, la sicurezza della circolazione e del territorio, il controllo della sosta e del decoro urbano. Al contempo, fornisce alle amministrazioni uno strumento efficace ed efficiente per processare le segnalazioni ricevute, nonché un vero e proprio Sistema di Supporto alle Decisioni per la pianificazione degli interventi o l'identificazione di politiche per la gestione e il controllo del territorio in ambito urbano. UrbIS è implementato come un web-gis basato sugli standard WFS-T e WMS; l'interfaccia è estremamente semplice ed intuitiva. Inoltre, la sua adesione a protocolli standard di comunicazione ne permette l'integrabilità con sistemi già esistenti. Abstract UrbIS (Urban Information System) is a Geographical Information System for the participative management of urban environments. With UrbIS, citizens and/or public officers may report to their administrations, in a simple and immediate way, the presence of specific problems occurring within the urban area concerning issues such as: maintenance of roads and urban space, safety and security of the municipal environment, control of parking and decorum. At the same time, it provides Public Administrations with an effective and efficient report management tool, and with a Decision Support System for planning interventions or policies for urban control. UrbIS is implemented as Web-GIS based on WFS-T and WMS standards; the user is simple and friendly. Moreover, his adherence to standard communication protocols allows the integration with other existing software.
ABSTRACT This article addresses the problem of simulating en-route path choices on transport netw... more ABSTRACT This article addresses the problem of simulating en-route path choices on transport networks. In particular, by rerouting, we mean changing the currently chosen path, after receiving some information about a traffic event. Indeed, when the forecasted performance pattern of travel times and costs, known or only perceived, changes significantly, drivers may react by shifting their current route to a better one. The representation of such situations is particularly challenging if the information reaches a driver who is already travelling toward the destination. At the state-of-the-practice, most traffic assignment models are not capable of reproducing these phenomena. We will model rerouting in the framework of within-day Dynamic Traffic Assignment (DTA). Two different solutions are presented here, both exploiting the rolling horizon technique. The first solution can be summarized as an alternate sequence of two fixed point problems for each traffic event: a Dynamic User Equilibrium (DUE) with warm start through saved flows, and a Dynamic Network Loading (DNL) for given route choices; this model is called DTA with Rolling Horizon Events (DTA-RHE) and allows setting the information time of each event before or after the event itself. The second one is a simplified version of the first one, under the assumption that all the events are communicated not later than their start time; this model is called DUE with Rolling Horizon Events (DUE-RHE), and is a sequence of Dynamic User Equilibria with warm start. Numerical examples show the results of the proposed models where rerouting phenomenon can be observed.
ABSTRACT A new continuous formulation of Dynamic Traffic Assignment, where a user equilibrium is ... more ABSTRACT A new continuous formulation of Dynamic Traffic Assignment, where a user equilibrium is expressed as a fixed point problem in terms of arc flow temporal profiles, is proposed. The precise aim of the paper is to integrate spillback modelling into an existing formulation of DTA, based on implicit path enumeration, which is capable of representing explicitly the formation and dispersion of vehicle queues on the road network, but allows the queue length to overcome the arc length. Specifically, we take into account the interaction among network links upstream and downstream road intersections deriving from time varying entering and exiting arc capacities due to vehicle queue spillovers, which is equivalent to introducing constraints on the queue lengths. To achieve this extension we introduce a sequence of models, that is the arc entering capacity model, the arc exiting capacity model, and the arc travel time model for time varying exiting capacity, describing, for given turning flow temporal profiles, the dynamic of the network nodes and arcs, and capable of representing the propagation of congestion among contiguous road links. Some numerical examples are devised to appreciate the relevant effect of spillback modelling in the context of DTA.
ABSTRACT What we assume to be typical state of the urban network, paradoxically, occurs very rare... more ABSTRACT What we assume to be typical state of the urban network, paradoxically, occurs very rarely. Unexpected events are frequent and cause network disruptions to drivers who were not aware of them. As reported in (Lomax et. al, 2012) more than 50% of all delay on the roads in the US is caused by unexpected events. Therefore it’s crucial to have models capable to capture consequences of the events on the network flows and performances. Hereby we investigate how state-of-the-practice Dynamic Traffic Assignment (DTA) models can be used to handle cases of unexpected events. We propose the Information Comply Model (ICM) to overcome limitations of DTA models. With ICM we extend DTA Route Choice Model to capture drivers’ reaction to the events in comprehensive and efficient form. We integrate ICM within the DTA fixedpoint problem and present the final algorithm. Paper is concluded with numerical examples both on toy and real-scale networks.
ABSTRACT Dynamic Traffic Assignment of travel demand to road networks can today support, on one s... more ABSTRACT Dynamic Traffic Assignment of travel demand to road networks can today support, on one side, transport planning and management through off-line equilibrium models, and on the other side, traffic monitoring and control through real-time propagation models. The former can explicitly reproduce vehicle queues along links and their spillback at intersections, thus overcoming the weak representation of congestion by volume delay functions affecting static assignment models. The latter can properly react to unpredicted events (accidents, road works) and control countermeasures (vms, traffic lights), thus overcoming the weak sensitivity of pattern recognition models. The traffic data (loop detectors, radar beams, video cameras, floating cars) continuously collected in the field can be used to calibrate/correct in real-time such DTA model. This approach allows to reconstruct the current and future traffic pattern on the entire network, hence extending the available data in time and space. The resulting information can be simply used to enhance driver navigation, or more actively to support optimal control strategies. OPTIMA is an innovative methodology that can integrate any software platform for traffic control centers, providing off-line estimates and real-time forecasts on the use (vehicle flows) and the performances (travel times) of the road network, through advanced DTA models and algorithms. A case study where the OPTIMA methodology has been applied to a large urban network is presented to show the feasibility of the proposed approach.
Schedule-Based Modeling of Transportation Networks
Abstract This paper propose a new approach for modelling congested transit networks with fixed ti... more Abstract This paper propose a new approach for modelling congested transit networks with fixed timetables where it may happen that there is not enough room onboard to allow all users waiting for a given line on the arriving carrier, so that passengers need to queue at ...
... Candidato Lorenzo Meschini Coordinatore Tutore Prof. Giuseppe Romolo Corazza Prof. Natale Pap... more ... Candidato Lorenzo Meschini Coordinatore Tutore Prof. Giuseppe Romolo Corazza Prof. Natale Papola Page 2. 2 ... 66 CAPITOLO 5 Modelli di equilibrio dinamico 69 5.1 Caricamento dinamico della rete 69 5.2 Mappa di carico della rete 70 5.3 Mappa di carico della rete Probit 70 ...
... Giuseppe Cantisani, Sapienza Università di Roma, Italy, giuseppe.cantisani@uniroma1.it Michel... more ... Giuseppe Cantisani, Sapienza Università di Roma, Italy, giuseppe.cantisani@uniroma1.it Michele Di Vito, Sapienza Università di Roma, Italy, michele ... elements (Dell'Acqua et al., 2007), altimetry (Gibreel et al., 2001), transversal characteristic of the road platform (Medina et al. ...
ABSTRACT OPTIMA is an innovative ITS (Intelligent Transport Systems) platform for traf-fic monito... more ABSTRACT OPTIMA is an innovative ITS (Intelligent Transport Systems) platform for traf-fic monitoring and management, that provides off-line estimates and real-time fore-casts concerning the use (vehicle flows) and the performances (travel times) of the road networks. To this end, OPTIMA exploits an advanced methodology for modelling transport demand and vehicle congestion, through which the behaviour of drivers and the propagation of queues are explicitly represented. The connection to actual conditions is guarantied by field measures at discrete points (loop detectors, speed radars, video cameras, probe vehicles) that are collected in real-time and sent to a control room, where sophisticated algorithms allow to reconstruct the current and future traffic pat-tern on the entire network, hence extending the available data in time and space to achieve a useful information for driver navigation and transport optimization.
... Dipartimento di Idraulica Trasporti e Strade - Università degli Studi di Roma “La Sapienza” V... more ... Dipartimento di Idraulica Trasporti e Strade - Università degli Studi di Roma “La Sapienza” Via Eudossiana 18, 00184 Roma [guido.gentile, lorenzo.meschini]@uniroma1.it °PTV – Planung ... 24. Mahut M., Florian M., Tremblay N., Campbell M., Patman D., Krnic McDaniel. ...
The objective of this paper is to present the application of a within-day Dynamic Traffic Assignm... more The objective of this paper is to present the application of a within-day Dynamic Traffic Assignment (DTA) Model to simulate ordinary, evacuation and emergency scenarios for downtown Vancouver during the forthcoming Winter Olympic Games. Within this context, the main problem was to simulate different kinds of pedestrians and vehicles-pedestrians interactions; these congestion phenomena can occur in presence of the unusual demand produced by important public events, such as sport games, music concerts and political rallies, when significant levels of pedestrian and vehicle flows are concentrated in space and time, i.e. converge to or diverge from one point/area in a relatively short time interval. Additionally, other phenomena that needed to be addressed where: - pedestrian route choice, since several routes are available to reach and leave event locations; - special event temporal demand, with time peaks concentrated around begin and end of events; - pedestrian capacity constraints, due to the limited capacity of road and sidewalks; - short term closure of streets, due to Olympic security measures. In order to address the above modeling needs, different approaches where considered, from classical static assignment, to meso simulation, to micro simulation applied to pedestrians and vehicles. Finally, a Macroscopic Dynamic Assignment model calculating Dynamic User Equilibrium was adopted, suitably extended in order to represent pedestrian flows and vehicle-pedestrian interactions.
Cerca percorso dinamico per reti di trasporto collettivo e spostamenti intermodali, che fornisce ... more Cerca percorso dinamico per reti di trasporto collettivo e spostamenti intermodali, che fornisce strategie ottimali per servizi a frequenza e ad orario considerando i ritardi alle fermate in tempo reale; registrato presso la SIAE in data 14.11.2011 con il n. 820
Cruscotto della mobilità accessibile via internet che calcola e presenta, anche su mappa, una ser... more Cruscotto della mobilità accessibile via internet che calcola e presenta, anche su mappa, una serie di indicatori per monitorare l’andamento e l’impatto del trasporto urbano, basati su misure di traffico ed emissioni con diverse aggregazioni spaziali e temporal
Assegnazione dinamica alle reti di trasporto collettivo con linee sia ad orario che a frequenza, ... more Assegnazione dinamica alle reti di trasporto collettivo con linee sia ad orario che a frequenza, in grado di simulare vincoli di capacità e fenomeni di congestione a bordo e alle fermat
Per sviluppare il Piano degli Spostamenti Casa – Lavoro relativo ai dipendenti di aziende medio-g... more Per sviluppare il Piano degli Spostamenti Casa – Lavoro relativo ai dipendenti di aziende medio-grandi; sulla base di questionari compilati via web, consente di simulare politiche di mobilità sostenibile mediante modelli di scelta modale; registrato presso la SIAE in data 14.11.2011 con il n. 821
In a recent paper [Bellei, Gentile and Papola, 2002] we have proposed a new continuous implicit p... more In a recent paper [Bellei, Gentile and Papola, 2002] we have proposed a new continuous implicit path formulation of Dynamic Traffic Assignment (D TA), where a user equilibrium is expressed as a fixed point problem in terms of arc flow temporal profiles. There, it is shown that, by extending to the dynamic case the concept of Network Loading Map, is no more needed to introduce the Continuous Dynamic Network Loading [see for instance Xu
ABSTRACT Sommario UrbIS (Urban Information System) è un Sistema Informativo Territoriale per la g... more ABSTRACT Sommario UrbIS (Urban Information System) è un Sistema Informativo Territoriale per la gestione partecipata degli ambienti urbani. Urbis consente infatti ai cittadini e/o agli operatori municipali di segnalare all'Amministrazioni Pubblica o più in generale ai gestori dei servizi, in maniera semplice ed immediata, la presenza sul territorio di specifici problemi relativi a tematiche quali: la manutenzione delle strade e dell'arredo cittadino, la sicurezza della circolazione e del territorio, il controllo della sosta e del decoro urbano. Al contempo, fornisce alle amministrazioni uno strumento efficace ed efficiente per processare le segnalazioni ricevute, nonché un vero e proprio Sistema di Supporto alle Decisioni per la pianificazione degli interventi o l'identificazione di politiche per la gestione e il controllo del territorio in ambito urbano. UrbIS è implementato come un web-gis basato sugli standard WFS-T e WMS; l'interfaccia è estremamente semplice ed intuitiva. Inoltre, la sua adesione a protocolli standard di comunicazione ne permette l'integrabilità con sistemi già esistenti. Abstract UrbIS (Urban Information System) is a Geographical Information System for the participative management of urban environments. With UrbIS, citizens and/or public officers may report to their administrations, in a simple and immediate way, the presence of specific problems occurring within the urban area concerning issues such as: maintenance of roads and urban space, safety and security of the municipal environment, control of parking and decorum. At the same time, it provides Public Administrations with an effective and efficient report management tool, and with a Decision Support System for planning interventions or policies for urban control. UrbIS is implemented as Web-GIS based on WFS-T and WMS standards; the user is simple and friendly. Moreover, his adherence to standard communication protocols allows the integration with other existing software.
ABSTRACT This article addresses the problem of simulating en-route path choices on transport netw... more ABSTRACT This article addresses the problem of simulating en-route path choices on transport networks. In particular, by rerouting, we mean changing the currently chosen path, after receiving some information about a traffic event. Indeed, when the forecasted performance pattern of travel times and costs, known or only perceived, changes significantly, drivers may react by shifting their current route to a better one. The representation of such situations is particularly challenging if the information reaches a driver who is already travelling toward the destination. At the state-of-the-practice, most traffic assignment models are not capable of reproducing these phenomena. We will model rerouting in the framework of within-day Dynamic Traffic Assignment (DTA). Two different solutions are presented here, both exploiting the rolling horizon technique. The first solution can be summarized as an alternate sequence of two fixed point problems for each traffic event: a Dynamic User Equilibrium (DUE) with warm start through saved flows, and a Dynamic Network Loading (DNL) for given route choices; this model is called DTA with Rolling Horizon Events (DTA-RHE) and allows setting the information time of each event before or after the event itself. The second one is a simplified version of the first one, under the assumption that all the events are communicated not later than their start time; this model is called DUE with Rolling Horizon Events (DUE-RHE), and is a sequence of Dynamic User Equilibria with warm start. Numerical examples show the results of the proposed models where rerouting phenomenon can be observed.
ABSTRACT A new continuous formulation of Dynamic Traffic Assignment, where a user equilibrium is ... more ABSTRACT A new continuous formulation of Dynamic Traffic Assignment, where a user equilibrium is expressed as a fixed point problem in terms of arc flow temporal profiles, is proposed. The precise aim of the paper is to integrate spillback modelling into an existing formulation of DTA, based on implicit path enumeration, which is capable of representing explicitly the formation and dispersion of vehicle queues on the road network, but allows the queue length to overcome the arc length. Specifically, we take into account the interaction among network links upstream and downstream road intersections deriving from time varying entering and exiting arc capacities due to vehicle queue spillovers, which is equivalent to introducing constraints on the queue lengths. To achieve this extension we introduce a sequence of models, that is the arc entering capacity model, the arc exiting capacity model, and the arc travel time model for time varying exiting capacity, describing, for given turning flow temporal profiles, the dynamic of the network nodes and arcs, and capable of representing the propagation of congestion among contiguous road links. Some numerical examples are devised to appreciate the relevant effect of spillback modelling in the context of DTA.
ABSTRACT What we assume to be typical state of the urban network, paradoxically, occurs very rare... more ABSTRACT What we assume to be typical state of the urban network, paradoxically, occurs very rarely. Unexpected events are frequent and cause network disruptions to drivers who were not aware of them. As reported in (Lomax et. al, 2012) more than 50% of all delay on the roads in the US is caused by unexpected events. Therefore it’s crucial to have models capable to capture consequences of the events on the network flows and performances. Hereby we investigate how state-of-the-practice Dynamic Traffic Assignment (DTA) models can be used to handle cases of unexpected events. We propose the Information Comply Model (ICM) to overcome limitations of DTA models. With ICM we extend DTA Route Choice Model to capture drivers’ reaction to the events in comprehensive and efficient form. We integrate ICM within the DTA fixedpoint problem and present the final algorithm. Paper is concluded with numerical examples both on toy and real-scale networks.
ABSTRACT Dynamic Traffic Assignment of travel demand to road networks can today support, on one s... more ABSTRACT Dynamic Traffic Assignment of travel demand to road networks can today support, on one side, transport planning and management through off-line equilibrium models, and on the other side, traffic monitoring and control through real-time propagation models. The former can explicitly reproduce vehicle queues along links and their spillback at intersections, thus overcoming the weak representation of congestion by volume delay functions affecting static assignment models. The latter can properly react to unpredicted events (accidents, road works) and control countermeasures (vms, traffic lights), thus overcoming the weak sensitivity of pattern recognition models. The traffic data (loop detectors, radar beams, video cameras, floating cars) continuously collected in the field can be used to calibrate/correct in real-time such DTA model. This approach allows to reconstruct the current and future traffic pattern on the entire network, hence extending the available data in time and space. The resulting information can be simply used to enhance driver navigation, or more actively to support optimal control strategies. OPTIMA is an innovative methodology that can integrate any software platform for traffic control centers, providing off-line estimates and real-time forecasts on the use (vehicle flows) and the performances (travel times) of the road network, through advanced DTA models and algorithms. A case study where the OPTIMA methodology has been applied to a large urban network is presented to show the feasibility of the proposed approach.
Schedule-Based Modeling of Transportation Networks
Abstract This paper propose a new approach for modelling congested transit networks with fixed ti... more Abstract This paper propose a new approach for modelling congested transit networks with fixed timetables where it may happen that there is not enough room onboard to allow all users waiting for a given line on the arriving carrier, so that passengers need to queue at ...
What we assume to be typical state of the urban network, paradoxically, occurs very rarely. Unexp... more What we assume to be typical state of the urban network, paradoxically, occurs very rarely. Unexpected events are frequent and cause network disruptions to drivers who were not aware of them. As reported in (Lomax et. al, 2012) more than 50{\%} of all delay on the roads in the US is caused by unexpected events. Therefore it's crucial to have models capable to capture consequences of the events on the network flows and performances. Hereby we investigate how state-of-the-practice Dynamic Traffic Assignment (DTA) models can be used to handle cases of unexpected events. We propose the Information Comply Model (ICM) to overcome limitations of DTA models. With ICM we extend DTA Route Choice Model to capture drivers' reaction to the events in comprehensive and efficient form. We integrate ICM within the DTA fixedpoint problem and present the final algorithm. Paper is concluded with numerical examples both on toy and real-scale networks.
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