Mode choice behaviour is often modelled by discrete choice models, in which the utility of each m... more Mode choice behaviour is often modelled by discrete choice models, in which the utility of each mode is characterized by mode-specific parameters reflecting how strongly the utility of that mode depends on attributes such as travel speed and cost, and a mode-specific constant value. For new modes, the mode-specific parameters and the constant in the utility function of discrete choice models are not known and are difficult to estimate on the basis of stated preferences data/choice experiments and cannot be estimated on the basis of revealed preference data. This paper demonstrates how revealed preference data can be used to estimate a discrete mode choice model without using mode-specific constants and mode-specific parameters. This establishes a method that can be used to analyze any new mode using revealed preference data and discrete choice models and is demonstrated using the OViN 2017 dataset with trips throughout the Netherlands using a multinomial and nested logit model. This...
Automated driving technology is emerging. Yet, less is known about when automated vehicles will h... more Automated driving technology is emerging. Yet, less is known about when automated vehicles will hit the market, how penetration rates will evolve and to what extent this new transportation technology will affect transportation demand and planning. This study identified through scenario analysis plausible future development paths of automated vehicles in the Netherlands and estimated potential implications for traffic, travel behavior and transport planning on a time horizon up to 2030 and 2050. The scenario analysis was performed through a series of three workshops engaging a group of diverse experts. Sixteen key factors and five driving forces behind them were identified as critical in determining future development of automated vehicles in the Netherlands. Four scenarios were constructed assuming combinations of high or low technological development and restrictive or supportive policies for automated vehicles (AV in standby, AV in bloom, AV in demand, AV in doubt). According ...
Verschillende studies hebben aangetoond dat delen van het Nederlandse wegennetwerk kwetsbaar zijn... more Verschillende studies hebben aangetoond dat delen van het Nederlandse wegennetwerk kwetsbaar zijn (bijv. Snelder et al., 2012). Kleine ongevallen of slechte weersomstandigheden kunnen al tot veel files en grote reistijdverliezen leiden. Een robuust wegennet, waarbij het netwerk minder vatbaar wordt voor kleine verstoringen wordt daarom steeds belangrijker. In de Visie Robuust Wegennet (Schrijver et al., 2008), ontwikkeld voor de ANWB, wordt op basis van een aantal algemene principes een plan geschetst hoe een robuuste structuur van het hoofdwegennet in de regio Rotterdam- Den Haag er uit zou kunnen zien. In deze visie nemen buffers een belangrijke plaats in. Er zijn drie typen buffers geidentificeerd: • natuurlijke bufferfunctie van wegvakken; • terugslagbuffers; • doseerbuffers. In dit rapport is aan de hand van een voorbeeldcase rondom de A13/Kruithuisplein (situatie 2010) met micro-simulatie inzichtelijk gemaakt wat het effect van een doseerbuffer kan zijn op het aantal voertuigv...
This paper studies and compares the gap selection process of multiple vehicle classes (passenger ... more This paper studies and compares the gap selection process of multiple vehicle classes (passenger cars, delivery vans, and trucks) within their discretionary lane changing activities. Given a trajectory or a sequence of gap selection decisions, we aim to predict whether a vehicle will change or keep a lane. For this purpose, we use a large trajectory dataset, collected for the Netherlands, consisting of 3,647 trajectories of passenger car drivers, 1,080 trajectories of delivery van drivers, and 2,226 trajectories of truck drivers. We apply gated recurrent unit neural networks to separately model their gap selection processes. These three models can not only handle class imbalance but also capture long-term interdependencies. The models can predict gap selection of three vehicle classes with geometric mean accuracies of 84% or higher. To obtain insights into their gap selection processes, we apply a gradient-based technique to analyze what neural networks have learned. Our results suggest that there exist significant differences between vehicle classes in terms of the importance of historical information and features. Trucks seem to value a relatively long period, recent 6 seconds, of driving experience to select gaps compared to passenger cars and delivery vans. In addition, the perception of road topology seems to be a significant factor for delivery vans and trucks, contrary to passenger cars which highly value their kinematic features and interactions with surrounding vehicles, to select gaps. These insights offer a novel contribution towards better understanding and modeling of the driving behavior of multiple vehicle classes. INDEX TERMS Driving behavior, discretionary lane-changing, gap selection, trajectory data, gated recurrent unit neural network, class imbalance, explainable AI.
Assessing travel time reliability and the robustness of networks (especially road networks in maj... more Assessing travel time reliability and the robustness of networks (especially road networks in major urban areas) is becoming more important as networks become more vulnerable. Especially in the Netherlands, the interconnectivity of networks of different scale is low and the level of usage is high, which leads to low spare capacities for unfavorable conditions. Also, the number of incidents is high and increasing. The Randstad area, lying between Amsterdam, The Hague, Utrecht and Rotterdam, experiences about 1750 incidents a year with a clearance time of over one hour. Already small disturbances can cause major disruptions on large parts of the network. As such we can expect that major benefits could be gained from measures that improve the stability of operating conditions of the road network under unfavorable circumstances. In 2008 the Dutch Ministry of Transport, Public Works and Water Management published the "MobiliteitsAanpak" (Mobility Approach) (Ministry of Transport, Public Works and Water Management, 2008). This policy document proposes investments in the Dutch road, rail, regional public transport and waterways network to improve travel times and their reliability and reduce negative external effects of transport. By assignment of the Dutch Ministry of Transport TNO evaluated the benefits of the Euro 30bn's worth of investment in the road network between 2020 and 2028. New in this analysis was that, in addition to travel time gains, we assessed the full reliability benefits of transport projects, where, next to the small travel time variations we also included the effects of major disruptions, where the robustness of the transport network is critical. Traditionally benefits related to improved travel time reliability were assessed using crude rules of thumb which are not related to the present or the future state of the network. In the Netherlands, a 25% markup is applied to travel time benefits. This number is based on Quantifying the full reliability benefits of road network improvements
De verwachting is dat de zelfrijdende auto op termijn gaat bijdragen aan het verbeteren van de do... more De verwachting is dat de zelfrijdende auto op termijn gaat bijdragen aan het verbeteren van de doorstroming, de verkeersveiligheid en de leefbaarheid. Zodra de zelfrijdende auto een substantiele trend is, wordt deze meegenomen in de afwegingen voor nieuwe infrastructuur, onder andere via de Nationale Markt en Capaciteits-Analyse (NMCA). Om hier klaar voor te zijn is een verkenning uitgevoerd naar de manier waarop de bereikbaarheids- en doorstromingseffecten van zelfrijdende auto's met het LMS kunnen worden berekend en het soort effecten dat zich voor kan doen. Bij de verkenning is een literatuurstudie uitgevoerd, is een expertsessie georganiseerd en zijn vijf verkennende modelruns met het LMS uitgevoerd: Run 1: afname van de capaciteit van het hoofdwegennetwerk met 5% (als de volgtijden groter worden). Run 2: toename van de capaciteit van het hoofdwegennetwerk met 15% (als de volgtijden kleiner worden). Run 3: combinatie run 2 + afname van de ruimte die vrachtwagens inneme...
In this contribution the Core Probability Framework (CPF) is introduced with the application of t... more In this contribution the Core Probability Framework (CPF) is introduced with the application of the Discrete-Element Core Probability Model (DE-CPM) as a new DNL for dynamic macroscopic modelling of stochastic traffic flow. The model is demonstrated for validation in a test case and for computational efficiency on two simple networks. The CPF extends a base model, such as the Cell Transmission Model (CTM), by considering each traffic variable as a discrete stochastic variable denoted as a probability distribution of values for each traffic variable in time and space. Traffic is propagated along a link using the base model and through a larger network with the application of probability merging algorithms at the nodes. Due to the incorporation of probability in the core of traffic propagation, the necessity for multiple acts as an internalisation of the Monte Carlo routine in the CPF for fast and efficient calculation of uncertainty. Initial tests cases show that the DE-CPM has the potential to reduce computation time multi-tenfold compared to regular Monte Carlo simulation. Such developments allow the application of stochastic dynamics traffic models to be more readily applied in practice.
Abstract A Field-Operational-Test (FOT) with CACC vehicles and wireless communication with intell... more Abstract A Field-Operational-Test (FOT) with CACC vehicles and wireless communication with intelligent intersections on arterial roads was performed in autumn 2018, initiated by the Province of Noord-Holland in The Netherlands. The goal of the pilot was to demonstrate the feasibility of CACC platooning and V2I/I2V (infrastructure-to-vehicle) communication and investigate the potential effects on traffic flow and safety in such an urban environment. During the pilot, seven CACC-enabled vehicles traversed a provincial road corridor, crossing five intelligent intersections, sending Cooperative Awareness Message (CAM) and receiving time-to-green information from Intelligent Traffic Signals (iTS). A simulation model was calibrated using the data from the pilot to give indications of the potential future effects of CACC and I2V communication. The results showed that full CACC penetration can lead to 5% lower travel times on average with an enhanced improvement when intelligent intersections with V2I/I2V technology is applied (11% lower). If scaled up to the provincial road network, this could lead to a reduction of 12% in the total experienced delay for road users. As for previous tests on motorways, a reduction in effectiveness was also found for lower CACC- penetration rates with penetration rates of 10% no longer showing any substantial gains.
Transportation Research Record: Journal of the Transportation Research Board, 2007
The Dutch national road network has been developed over centuries. In the past, roads were constr... more The Dutch national road network has been developed over centuries. In the past, roads were constructed according to contemporary spatial and transportation planning philosophies. Because the existing road network is a result of a long process of successive developments, the question can be asked whether this network is the most appropriate currently, especially considering the socioeconomic structure of the Netherlands. To answer this question, an optimization algorithm has been developed for designing road networks for a given spatial structure of cities, villages, and industrial activities. With this algorithm, the Dutch road network is redesigned on the basis of minimization of the travel and infrastructure costs and by taking into account the socioeconomic structure of the Netherlands. A comparison between the existing network and the new design shows that the redesigned Dutch national road network has significantly lower total costs than the existing road network. It is found t...
It is computationally expensive to find out where vulnerable parts in a network are. In literatur... more It is computationally expensive to find out where vulnerable parts in a network are. In literature a variety of methods were introduced that use relatively simple selection criteria (measured in real-life or calculated in a traffic simulator) to pre-determine the seriousness of the delays caused by the blocking of that link and thereafter perform a more detailed analysis. This paper reviews the selection criteria proposed in the literature and assesses the quality of these criteria. Furthermore, a multi-linear fit of the criteria is made to find a better, combined, criterion to rank the links according to their vulnerability. The paper shows that different criteria indicate different links to be vulnerable. Also combined they cannot well predict the vulnerability of a link. Therefore, it is concluded that to find vulnerable links, one has to look further than link-based indicators. Knoop, Snelder, Van Zuylen, Hoogendoorn 3 1
In this contribution the Core Probability Framework (CPF) is introduced with the application of t... more In this contribution the Core Probability Framework (CPF) is introduced with the application of the Discrete-Element Core Probability Model (DE-CPM) as a new DNL for dynamic macroscopic modelling of stochastic traffic flow. The model is demonstrated for validation in a test case and for computational efficiency on two simple networks. The CPF extends a base model, such as the Cell Transmission Model (CTM), by considering each traffic variable as a discrete stochastic variable denoted as a probability distribution of values for each traffic variable in time and space. Traffic is propagated along a link using the base model and through a larger network with the application of probability merging algorithms at the nodes. Due to the incorporation of probability in the core of traffic propagation, the necessity for multiple acts as an internalisation of the Monte Carlo routine in the CPF for fast and efficient calculation of uncertainty. Initial tests cases show that the DE-CPM has the p...
Onlangs heeft de Nederlandse media veel aandacht besteed aan een herontwerp van het Nederlandse w... more Onlangs heeft de Nederlandse media veel aandacht besteed aan een herontwerp van het Nederlandse wegennetwerk. Dit herontwerp is gemaakt om de behoefte aan infrastructuur te scheten. Bovendien kan een vergelijking met het bestaande netwerk inzichten geven in de punten waarop het netwerk verbeterd kan worden. Verschillende kranten en nieuwsrubrieken hebben over het herontwerp van het wegennetwerk geschreven. Waar in het begin de krantenartikelen nog volledig en correct waren, verdween bij de latere stukken al snel de nuance en werden ook de feiten niet altijd meer correct weergegeven. De vele reacties die daarop volgden van ministeries, verkeerskundigen milieuorganisaties en vooral particulieren waren heel divers. Hoe komt dit? Hoe erg is dit? Deze twee vragen worden beantwoord door enkele discussiepunten uit te lichten. Een voorbeeld van een punt waar veel misverstand over bestaat is de vraag of in het herontwerp nog file staat. Een van de bladen kopte met “Nooit meer file” en in een...
Traffic is affected by a wide range of variables. An influential and commonly occurring variable ... more Traffic is affected by a wide range of variables. An influential and commonly occurring variable on traffic flow is the weather. Weather conditions affect both traffic demand as well as road capacity and in doing so also affect the traffic fluency, or rather the ability of traffic to maintain a certain level-of-service. In this contribution it is argued that the influence of weather should be considered holistically for simultaneous influence on both the demand and supply. Furthermore, a case is made to quantify such outcomes stochastically, as traffic is rarely in an average state, especially when considering such stochastic variables as the weather. This is backed up by an extensive data analysis into the effects of rain, snow, temperature and wind on road capacity, traffic demand and traffic fluency. This found the effects on the traffic fluency of rain to be limited due to a reduction in both capacity and demand on relevant days. The effect of cold temperatures was especially sh...
In Amsterdam is het eerste real time verkeersmodel voor plezier- en beroepsvaart ontwikkeld voor ... more In Amsterdam is het eerste real time verkeersmodel voor plezier- en beroepsvaart ontwikkeld voor de Amsterdamse grachten. In de Amsterdamse grachten neemt de laatste jaren het aantal boten voor rondvaart, goederenvervoer en pleziervaart toe, dus ook de daarbij behorende drukte en overlast. Stichting Waternet, verantwoordelijk voor het in goede banen leiden van het verkeer over water, wil de drukte van dit verkeer in kaart brengen om het efficient te kunnen sturen. Er zijn op 17 strategische punten in de grachten van Amsterdam speciale sensoren opgehangen waarmee passerende boten (anoniem) worden geteld. Die sensoren meten de richting, lengte en gemiddelde snelheid van de boten die langs varen. Deze gegevens worden samen met de locatiegegevens van de gebruikers van de speciale VaarwaterApp gebruikt om ieder kwartier een drukteverwachting en actueel overzicht van de drukte op de grachten te maken met een microsimulatiemodel. Daarnaast kan met de offline-versie van het model het effect...
Mode choice behaviour is often modelled by discrete choice models, in which the utility of each m... more Mode choice behaviour is often modelled by discrete choice models, in which the utility of each mode is characterized by mode-specific parameters reflecting how strongly the utility of that mode depends on attributes such as travel speed and cost, and a mode-specific constant value. For new modes, the mode-specific parameters and the constant in the utility function of discrete choice models are not known and are difficult to estimate on the basis of stated preferences data/choice experiments and cannot be estimated on the basis of revealed preference data. This paper demonstrates how revealed preference data can be used to estimate a discrete mode choice model without using mode-specific constants and mode-specific parameters. This establishes a method that can be used to analyze any new mode using revealed preference data and discrete choice models and is demonstrated using the OViN 2017 dataset with trips throughout the Netherlands using a multinomial and nested logit model. This...
Automated driving technology is emerging. Yet, less is known about when automated vehicles will h... more Automated driving technology is emerging. Yet, less is known about when automated vehicles will hit the market, how penetration rates will evolve and to what extent this new transportation technology will affect transportation demand and planning. This study identified through scenario analysis plausible future development paths of automated vehicles in the Netherlands and estimated potential implications for traffic, travel behavior and transport planning on a time horizon up to 2030 and 2050. The scenario analysis was performed through a series of three workshops engaging a group of diverse experts. Sixteen key factors and five driving forces behind them were identified as critical in determining future development of automated vehicles in the Netherlands. Four scenarios were constructed assuming combinations of high or low technological development and restrictive or supportive policies for automated vehicles (AV in standby, AV in bloom, AV in demand, AV in doubt). According ...
Verschillende studies hebben aangetoond dat delen van het Nederlandse wegennetwerk kwetsbaar zijn... more Verschillende studies hebben aangetoond dat delen van het Nederlandse wegennetwerk kwetsbaar zijn (bijv. Snelder et al., 2012). Kleine ongevallen of slechte weersomstandigheden kunnen al tot veel files en grote reistijdverliezen leiden. Een robuust wegennet, waarbij het netwerk minder vatbaar wordt voor kleine verstoringen wordt daarom steeds belangrijker. In de Visie Robuust Wegennet (Schrijver et al., 2008), ontwikkeld voor de ANWB, wordt op basis van een aantal algemene principes een plan geschetst hoe een robuuste structuur van het hoofdwegennet in de regio Rotterdam- Den Haag er uit zou kunnen zien. In deze visie nemen buffers een belangrijke plaats in. Er zijn drie typen buffers geidentificeerd: • natuurlijke bufferfunctie van wegvakken; • terugslagbuffers; • doseerbuffers. In dit rapport is aan de hand van een voorbeeldcase rondom de A13/Kruithuisplein (situatie 2010) met micro-simulatie inzichtelijk gemaakt wat het effect van een doseerbuffer kan zijn op het aantal voertuigv...
This paper studies and compares the gap selection process of multiple vehicle classes (passenger ... more This paper studies and compares the gap selection process of multiple vehicle classes (passenger cars, delivery vans, and trucks) within their discretionary lane changing activities. Given a trajectory or a sequence of gap selection decisions, we aim to predict whether a vehicle will change or keep a lane. For this purpose, we use a large trajectory dataset, collected for the Netherlands, consisting of 3,647 trajectories of passenger car drivers, 1,080 trajectories of delivery van drivers, and 2,226 trajectories of truck drivers. We apply gated recurrent unit neural networks to separately model their gap selection processes. These three models can not only handle class imbalance but also capture long-term interdependencies. The models can predict gap selection of three vehicle classes with geometric mean accuracies of 84% or higher. To obtain insights into their gap selection processes, we apply a gradient-based technique to analyze what neural networks have learned. Our results suggest that there exist significant differences between vehicle classes in terms of the importance of historical information and features. Trucks seem to value a relatively long period, recent 6 seconds, of driving experience to select gaps compared to passenger cars and delivery vans. In addition, the perception of road topology seems to be a significant factor for delivery vans and trucks, contrary to passenger cars which highly value their kinematic features and interactions with surrounding vehicles, to select gaps. These insights offer a novel contribution towards better understanding and modeling of the driving behavior of multiple vehicle classes. INDEX TERMS Driving behavior, discretionary lane-changing, gap selection, trajectory data, gated recurrent unit neural network, class imbalance, explainable AI.
Assessing travel time reliability and the robustness of networks (especially road networks in maj... more Assessing travel time reliability and the robustness of networks (especially road networks in major urban areas) is becoming more important as networks become more vulnerable. Especially in the Netherlands, the interconnectivity of networks of different scale is low and the level of usage is high, which leads to low spare capacities for unfavorable conditions. Also, the number of incidents is high and increasing. The Randstad area, lying between Amsterdam, The Hague, Utrecht and Rotterdam, experiences about 1750 incidents a year with a clearance time of over one hour. Already small disturbances can cause major disruptions on large parts of the network. As such we can expect that major benefits could be gained from measures that improve the stability of operating conditions of the road network under unfavorable circumstances. In 2008 the Dutch Ministry of Transport, Public Works and Water Management published the "MobiliteitsAanpak" (Mobility Approach) (Ministry of Transport, Public Works and Water Management, 2008). This policy document proposes investments in the Dutch road, rail, regional public transport and waterways network to improve travel times and their reliability and reduce negative external effects of transport. By assignment of the Dutch Ministry of Transport TNO evaluated the benefits of the Euro 30bn's worth of investment in the road network between 2020 and 2028. New in this analysis was that, in addition to travel time gains, we assessed the full reliability benefits of transport projects, where, next to the small travel time variations we also included the effects of major disruptions, where the robustness of the transport network is critical. Traditionally benefits related to improved travel time reliability were assessed using crude rules of thumb which are not related to the present or the future state of the network. In the Netherlands, a 25% markup is applied to travel time benefits. This number is based on Quantifying the full reliability benefits of road network improvements
De verwachting is dat de zelfrijdende auto op termijn gaat bijdragen aan het verbeteren van de do... more De verwachting is dat de zelfrijdende auto op termijn gaat bijdragen aan het verbeteren van de doorstroming, de verkeersveiligheid en de leefbaarheid. Zodra de zelfrijdende auto een substantiele trend is, wordt deze meegenomen in de afwegingen voor nieuwe infrastructuur, onder andere via de Nationale Markt en Capaciteits-Analyse (NMCA). Om hier klaar voor te zijn is een verkenning uitgevoerd naar de manier waarop de bereikbaarheids- en doorstromingseffecten van zelfrijdende auto's met het LMS kunnen worden berekend en het soort effecten dat zich voor kan doen. Bij de verkenning is een literatuurstudie uitgevoerd, is een expertsessie georganiseerd en zijn vijf verkennende modelruns met het LMS uitgevoerd: Run 1: afname van de capaciteit van het hoofdwegennetwerk met 5% (als de volgtijden groter worden). Run 2: toename van de capaciteit van het hoofdwegennetwerk met 15% (als de volgtijden kleiner worden). Run 3: combinatie run 2 + afname van de ruimte die vrachtwagens inneme...
In this contribution the Core Probability Framework (CPF) is introduced with the application of t... more In this contribution the Core Probability Framework (CPF) is introduced with the application of the Discrete-Element Core Probability Model (DE-CPM) as a new DNL for dynamic macroscopic modelling of stochastic traffic flow. The model is demonstrated for validation in a test case and for computational efficiency on two simple networks. The CPF extends a base model, such as the Cell Transmission Model (CTM), by considering each traffic variable as a discrete stochastic variable denoted as a probability distribution of values for each traffic variable in time and space. Traffic is propagated along a link using the base model and through a larger network with the application of probability merging algorithms at the nodes. Due to the incorporation of probability in the core of traffic propagation, the necessity for multiple acts as an internalisation of the Monte Carlo routine in the CPF for fast and efficient calculation of uncertainty. Initial tests cases show that the DE-CPM has the potential to reduce computation time multi-tenfold compared to regular Monte Carlo simulation. Such developments allow the application of stochastic dynamics traffic models to be more readily applied in practice.
Abstract A Field-Operational-Test (FOT) with CACC vehicles and wireless communication with intell... more Abstract A Field-Operational-Test (FOT) with CACC vehicles and wireless communication with intelligent intersections on arterial roads was performed in autumn 2018, initiated by the Province of Noord-Holland in The Netherlands. The goal of the pilot was to demonstrate the feasibility of CACC platooning and V2I/I2V (infrastructure-to-vehicle) communication and investigate the potential effects on traffic flow and safety in such an urban environment. During the pilot, seven CACC-enabled vehicles traversed a provincial road corridor, crossing five intelligent intersections, sending Cooperative Awareness Message (CAM) and receiving time-to-green information from Intelligent Traffic Signals (iTS). A simulation model was calibrated using the data from the pilot to give indications of the potential future effects of CACC and I2V communication. The results showed that full CACC penetration can lead to 5% lower travel times on average with an enhanced improvement when intelligent intersections with V2I/I2V technology is applied (11% lower). If scaled up to the provincial road network, this could lead to a reduction of 12% in the total experienced delay for road users. As for previous tests on motorways, a reduction in effectiveness was also found for lower CACC- penetration rates with penetration rates of 10% no longer showing any substantial gains.
Transportation Research Record: Journal of the Transportation Research Board, 2007
The Dutch national road network has been developed over centuries. In the past, roads were constr... more The Dutch national road network has been developed over centuries. In the past, roads were constructed according to contemporary spatial and transportation planning philosophies. Because the existing road network is a result of a long process of successive developments, the question can be asked whether this network is the most appropriate currently, especially considering the socioeconomic structure of the Netherlands. To answer this question, an optimization algorithm has been developed for designing road networks for a given spatial structure of cities, villages, and industrial activities. With this algorithm, the Dutch road network is redesigned on the basis of minimization of the travel and infrastructure costs and by taking into account the socioeconomic structure of the Netherlands. A comparison between the existing network and the new design shows that the redesigned Dutch national road network has significantly lower total costs than the existing road network. It is found t...
It is computationally expensive to find out where vulnerable parts in a network are. In literatur... more It is computationally expensive to find out where vulnerable parts in a network are. In literature a variety of methods were introduced that use relatively simple selection criteria (measured in real-life or calculated in a traffic simulator) to pre-determine the seriousness of the delays caused by the blocking of that link and thereafter perform a more detailed analysis. This paper reviews the selection criteria proposed in the literature and assesses the quality of these criteria. Furthermore, a multi-linear fit of the criteria is made to find a better, combined, criterion to rank the links according to their vulnerability. The paper shows that different criteria indicate different links to be vulnerable. Also combined they cannot well predict the vulnerability of a link. Therefore, it is concluded that to find vulnerable links, one has to look further than link-based indicators. Knoop, Snelder, Van Zuylen, Hoogendoorn 3 1
In this contribution the Core Probability Framework (CPF) is introduced with the application of t... more In this contribution the Core Probability Framework (CPF) is introduced with the application of the Discrete-Element Core Probability Model (DE-CPM) as a new DNL for dynamic macroscopic modelling of stochastic traffic flow. The model is demonstrated for validation in a test case and for computational efficiency on two simple networks. The CPF extends a base model, such as the Cell Transmission Model (CTM), by considering each traffic variable as a discrete stochastic variable denoted as a probability distribution of values for each traffic variable in time and space. Traffic is propagated along a link using the base model and through a larger network with the application of probability merging algorithms at the nodes. Due to the incorporation of probability in the core of traffic propagation, the necessity for multiple acts as an internalisation of the Monte Carlo routine in the CPF for fast and efficient calculation of uncertainty. Initial tests cases show that the DE-CPM has the p...
Onlangs heeft de Nederlandse media veel aandacht besteed aan een herontwerp van het Nederlandse w... more Onlangs heeft de Nederlandse media veel aandacht besteed aan een herontwerp van het Nederlandse wegennetwerk. Dit herontwerp is gemaakt om de behoefte aan infrastructuur te scheten. Bovendien kan een vergelijking met het bestaande netwerk inzichten geven in de punten waarop het netwerk verbeterd kan worden. Verschillende kranten en nieuwsrubrieken hebben over het herontwerp van het wegennetwerk geschreven. Waar in het begin de krantenartikelen nog volledig en correct waren, verdween bij de latere stukken al snel de nuance en werden ook de feiten niet altijd meer correct weergegeven. De vele reacties die daarop volgden van ministeries, verkeerskundigen milieuorganisaties en vooral particulieren waren heel divers. Hoe komt dit? Hoe erg is dit? Deze twee vragen worden beantwoord door enkele discussiepunten uit te lichten. Een voorbeeld van een punt waar veel misverstand over bestaat is de vraag of in het herontwerp nog file staat. Een van de bladen kopte met “Nooit meer file” en in een...
Traffic is affected by a wide range of variables. An influential and commonly occurring variable ... more Traffic is affected by a wide range of variables. An influential and commonly occurring variable on traffic flow is the weather. Weather conditions affect both traffic demand as well as road capacity and in doing so also affect the traffic fluency, or rather the ability of traffic to maintain a certain level-of-service. In this contribution it is argued that the influence of weather should be considered holistically for simultaneous influence on both the demand and supply. Furthermore, a case is made to quantify such outcomes stochastically, as traffic is rarely in an average state, especially when considering such stochastic variables as the weather. This is backed up by an extensive data analysis into the effects of rain, snow, temperature and wind on road capacity, traffic demand and traffic fluency. This found the effects on the traffic fluency of rain to be limited due to a reduction in both capacity and demand on relevant days. The effect of cold temperatures was especially sh...
In Amsterdam is het eerste real time verkeersmodel voor plezier- en beroepsvaart ontwikkeld voor ... more In Amsterdam is het eerste real time verkeersmodel voor plezier- en beroepsvaart ontwikkeld voor de Amsterdamse grachten. In de Amsterdamse grachten neemt de laatste jaren het aantal boten voor rondvaart, goederenvervoer en pleziervaart toe, dus ook de daarbij behorende drukte en overlast. Stichting Waternet, verantwoordelijk voor het in goede banen leiden van het verkeer over water, wil de drukte van dit verkeer in kaart brengen om het efficient te kunnen sturen. Er zijn op 17 strategische punten in de grachten van Amsterdam speciale sensoren opgehangen waarmee passerende boten (anoniem) worden geteld. Die sensoren meten de richting, lengte en gemiddelde snelheid van de boten die langs varen. Deze gegevens worden samen met de locatiegegevens van de gebruikers van de speciale VaarwaterApp gebruikt om ieder kwartier een drukteverwachting en actueel overzicht van de drukte op de grachten te maken met een microsimulatiemodel. Daarnaast kan met de offline-versie van het model het effect...
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