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Gurcan Comert - One of the best experts on this subject based on the ideXlab platform.
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cycle to cycle queue length estimation from connected vehicles with filtering on primary parameters
International journal of transportation science and technology, 2021Co-Authors: Gurcan Comert, Negash BegashawAbstract:Abstract Estimation models from connected vehicles often assume low level parameters such as arrival rates and Market Penetration rates as known or estimate them in real-time. At low Market Penetration rates, such parameter estimators produce large errors making estimated queue lengths inefficient for control or operations applications. In order to improve accuracy of low level parameter estimations, this study investigates the impact of connected vehicles information filtering on queue length estimation models. Filters are used as multilevel real-time estimators. Accuracy is tested against known arrival rate and Market Penetration rate scenarios using microsimulations. To understand the effectiveness for short-term or for dynamic processes, arrival rates, and Market Penetration rates are changed every 15 min. The results show that with Kalman and Particle filters, parameter estimators are able to find the true values within 15 min and meet and surpass the accuracy of known parameter scenarios especially for low Market Penetration rates. In addition, using last known estimated queue lengths when no connected vehicle is present performs better than inputting average estimated values. Moreover, the study shows that both filtering algorithms are suitable for real-time applications that require less than 0.1 second computational time.
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cycle to cycle queue length estimation from connected vehicles with filtering on primary parameters
arXiv: Applications, 2020Co-Authors: Gurcan Comert, Negash BegashawAbstract:Estimation models from connected vehicles often assume low level parameters such as arrival rates and Market Penetration rates as known or estimate them in real-time. At low Market Penetration rates, such parameter estimators produce large errors making estimated queue lengths inefficient for control or operations applications. In order to improve accuracy of low level parameter estimations, this study investigates the impact of connected vehicles information filtering on queue length estimation models. Filters are used as multilevel real-time estimators. Accuracy is tested against known arrival rate and Market Penetration rate scenarios using microsimulations. To understand the effectiveness for short-term or for dynamic processes, arrival rates, and Market Penetration rates are changed every 15 minutes. The results show that with Kalman and Particle filters, parameter estimators are able to find the true values within 15 minutes and meet and surpass the accuracy of known parameter scenarios especially for low Market Penetration rates. In addition, using last known estimated queue lengths when no connected vehicle is present performs better than inputting average estimated values. Moreover, the study shows that both filtering algorithms are suitable for real-time applications that require less than 0.1 second computational time.
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effect of stop line detection in queue length estimation at traffic signals from probe vehicles data
European Journal of Operational Research, 2013Co-Authors: Gurcan ComertAbstract:Abstract Stop line detectors are one of the most deployed traffic data collection technologies at signalized intersections today. Newly emerging probe vehicles are increasingly receiving more attention as an alternative means of real-time monitoring for better system operations, however, high Market Penetration levels are not expected in the near future. This paper focuses on real-time estimation of queue lengths by combining these two data types, i.e., actuation from stop line detectors with location and time information from probe vehicles, at isolated and undersaturated intersections. Using basic principles of statistical point estimation, analytical models are developed for the expected total queue length and its variance at the end of red interval. The study addresses the evaluation of such estimators as a function of the Market Penetration of probe vehicles. Accuracy of the developed models is compared using a microscopic simulation environment-VISSIM. Various numerical examples are presented to show how estimation errors behave by the inclusion of stop line detection for different volume to capacity ratio and Market Penetration levels. Results indicate that the addition of stop line detection improves the estimation accuracy as much as 14% when overflow queue is ignored and 24% when overflow queue is included for less than 5% probe Penetration level.
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queue length estimation from probe vehicle location and the impacts of sample size
European Journal of Operational Research, 2009Co-Authors: Gurcan Comert, Mecit CetinAbstract:Probe vehicles are increasingly receiving more attention as an alternative means of collecting real-time traffic data needed for system optimization. This paper focuses on real-time estimation of queue lengths from the location information of probe vehicles in a queue at an isolated and undersaturated intersection. The paper also addresses the evaluation of the accuracy of such estimates as a function of the Market Penetration of probe vehicles. An analytical formulation based on conditional probability distributions is developed for estimating the expected queue length and its variance. It is found that, for the given settings, only the location information of the last probe vehicle in the queue is sufficient for the estimation. Exact expressions for the conditional mean and variance of queue length are derived. Various numerical results are documented to show how estimation errors behave by the volume to capacity ratio and by Market Penetration.
Carla Silva - One of the best experts on this subject based on the ideXlab platform.
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Plug-in hybrid fuel cell vehicles Market Penetration scenarios
International Journal of Hydrogen Energy, 2010Co-Authors: Patrícia Baptista, Mário Tomás, Carla SilvaAbstract:Abstract The main objective of this research is to analyze the impact of the Market share increase of hydrogen based road vehicles in terms of energy consumption and CO2, on today's Portuguese light-duty fleet. Actual yearly values of energy consumption and emissions were estimated using COPERT software: 167112 TJ of fossil fuel energy, 12213 kton of CO2 emission and 141 kton of CO, 20 kton of HC, 46 kton of NOx and 3 kton of PM. These values represent 20–40% of countries total emissions. Additionally to base fleet, three scenarios of introduction of 10–30% fuel cell vehicles including plug-in hybrids configurations were analysed. Considering the scenarios of increasing hydrogen based vehicles Penetration, up to 10% life cycle energy consumption reduction can be obtained if hydrogen from centralized natural gas reforming is considered. Full life cycle CO2 emissions can also be reduced up to 20% in these scenarios, while local pollutants reach up to 85% reductions. For the purpose of estimating road vehicle technologies energy consumption and CO2 emissions in a full life cycle perspective, fuel cell, conventional full hybrids and hybrid plug-in technologies were considered with diesel, gasoline, hydrogen and biofuel blends. Energy consumption values were estimated in a real road driving cycle and with ADVISOR software. Materials cradle-to-grave life cycle was estimated using GREET database adapted to Europe electric mix. The main conclusions on CO2 full life cycle analysis is that light-duty vehicles using fuel cell propulsion technology are highly dependent on hydrogen production pathway. The worst scenario for the current Portuguese and European electric mix is hydrogen produced from on-site electrolysis (in the refuelling stations). In this case full life cycle CO2 is 270 g/km against 190 g/km for conventional Diesel vehicle, for a typical 150,000 km useful life. A brief energy price analysis was presented. We conclude that hydrogen price equivalent to gasoline energy price (€/MJ) is important to the consumer preference of hydrogen based vehicles. It is also possible a fuel cell cost comparable with internal combustion engine cost if sufficient Market Penetration and power density increase are attained.
Kay W Axhausen - One of the best experts on this subject based on the ideXlab platform.
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the economics of motorist information systems revisited in transport and information systems
Classics in Transport Analysis, 2003Co-Authors: Rhm Emmerink, Peter Nijkamp, Piet Rietveld, Kay W AxhausenAbstract:This paper aims to shed more light on potential economic costs and benefits associated with new motorist information systems, particularly with respect to economic consequences, by reviewing and combining results obtained in the literature. In addition, future research directions, essential for increased understanding of these systems, are provided. Ultimately, it is concluded that the implementation of a motorist information system will, owing to an efficiency improvement on the road network, generate more traffic. The size of this newly generated traffic is uncertain and is dependent on the kind of information system, behavioral responses of the road users, the particular network under consideration, and the level of Market Penetration. The benefits to equipped drivers seem to diminish as the level of Market Penetration increases.
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the potential of information provision in a simulated road transport network with non recurrent congestion
Transportation Research Part C-emerging Technologies, 1995Co-Authors: Rhm Emmerink, Kay W Axhausen, Peter Nijkamp, Piet RietveldAbstract:Abstract This paper analyses the potential of advanced traveller information systems (ATIS) in a road network in which incidents are generated in a random fashion. A simulation model is applied in which the traffic flows are the aggregation of drivers' decisions. These decisions, in turn, are modelled using boundedly rational principles. The experiments performed focus on the relationship between the network wide performance, the level of Market Penetration, the quality of the information, and the en route switching propensity. The results indicate that if drivers behave according to boundedly rational principles without being provided with information in a road network with non-recurrent congestion, the road network will not be used efficiently in terms of travel time. In these circumstances, ATIS is useful. However, the commercial viability of ATIS might be frustrated by the quickly diminishing additional benefits to equipped drivers. Further, the complexity of the implications of ATIS is stressed by the strong interaction between, on the one hand, the level of Market Penetration, the quality of the information and the en route switching propensity and, on the other hand, the network wide performance.
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effects of information in road transport networks with recurrent congestion
Transportation, 1995Co-Authors: Rhm Emmerink, Kay W Axhausen, Peter Nijkamp, Piet RietveldAbstract:This paper aims to gain more insight into the implications of information provision to drivers on the performance of road transport networks with recurrent congestion. For this purpose, a simulation program consisting of three components has been written. The first component is the traffic simulation model, the second component is the information provision mechanism, and the third component monitors the behavioural decision-making process of the drivers, which is modelled using a utility-based satisficing principle. Three types of information provision mechanisms will be considered: information based upon own-experience, after-trip information and real-time en route information. The findings in this paper, obtained in a hypothetical context, underline the important relationship betweenoverreaction, thelevel of Market Penetration and thequality of the information. High quality information allows a high level of Market Penetration, while low quality information, even when provided at low levels of Market Penetration, induces overreaction. Furthermore, real-time en route information is in particular beneficial during the process leading to a steady state; it reduces the variance in travel time considerably. The paper concludes with a discussion on the Market potential of motorist information systems when commercially Marketed.
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the economics of motorist information systems revisited
Transport Reviews, 1994Co-Authors: Rhm Emmerink, Peter Nijkamp, Piet Rietveld, Kay W AxhausenAbstract:The literature on the implications of the implementation of motorist information systems is ambiguous, particularly with respect to the economic consequences. This paper aims to shed more light on the potential economic costs and benefits of these new technologies by reviewing and combining results obtained in the literature. Furthermore, future research directions, essential for an increased understanding of these systems, are pointed out. It is first argued that a motorist information system is not a normal economic good; the benefits accruing to the equipped road users are dependent on the level of Market Penetration. At most levels of Market Penetration a motorist information system is most likely to generate a positive external effect for non‐equipped motorists and a negative external effect for those already equipped. However, in terms of travel time, the equipped road users will outperform the non‐equipped ones. Next, the economic consequences of these peculiarities are identified, particularly wit...
Rhm Emmerink - One of the best experts on this subject based on the ideXlab platform.
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the economics of motorist information systems revisited in transport and information systems
Classics in Transport Analysis, 2003Co-Authors: Rhm Emmerink, Peter Nijkamp, Piet Rietveld, Kay W AxhausenAbstract:This paper aims to shed more light on potential economic costs and benefits associated with new motorist information systems, particularly with respect to economic consequences, by reviewing and combining results obtained in the literature. In addition, future research directions, essential for increased understanding of these systems, are provided. Ultimately, it is concluded that the implementation of a motorist information system will, owing to an efficiency improvement on the road network, generate more traffic. The size of this newly generated traffic is uncertain and is dependent on the kind of information system, behavioral responses of the road users, the particular network under consideration, and the level of Market Penetration. The benefits to equipped drivers seem to diminish as the level of Market Penetration increases.
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the potential of information provision in a simulated road transport network with non recurrent congestion
Transportation Research Part C-emerging Technologies, 1995Co-Authors: Rhm Emmerink, Kay W Axhausen, Peter Nijkamp, Piet RietveldAbstract:Abstract This paper analyses the potential of advanced traveller information systems (ATIS) in a road network in which incidents are generated in a random fashion. A simulation model is applied in which the traffic flows are the aggregation of drivers' decisions. These decisions, in turn, are modelled using boundedly rational principles. The experiments performed focus on the relationship between the network wide performance, the level of Market Penetration, the quality of the information, and the en route switching propensity. The results indicate that if drivers behave according to boundedly rational principles without being provided with information in a road network with non-recurrent congestion, the road network will not be used efficiently in terms of travel time. In these circumstances, ATIS is useful. However, the commercial viability of ATIS might be frustrated by the quickly diminishing additional benefits to equipped drivers. Further, the complexity of the implications of ATIS is stressed by the strong interaction between, on the one hand, the level of Market Penetration, the quality of the information and the en route switching propensity and, on the other hand, the network wide performance.
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effects of information in road transport networks with recurrent congestion
Transportation, 1995Co-Authors: Rhm Emmerink, Kay W Axhausen, Peter Nijkamp, Piet RietveldAbstract:This paper aims to gain more insight into the implications of information provision to drivers on the performance of road transport networks with recurrent congestion. For this purpose, a simulation program consisting of three components has been written. The first component is the traffic simulation model, the second component is the information provision mechanism, and the third component monitors the behavioural decision-making process of the drivers, which is modelled using a utility-based satisficing principle. Three types of information provision mechanisms will be considered: information based upon own-experience, after-trip information and real-time en route information. The findings in this paper, obtained in a hypothetical context, underline the important relationship betweenoverreaction, thelevel of Market Penetration and thequality of the information. High quality information allows a high level of Market Penetration, while low quality information, even when provided at low levels of Market Penetration, induces overreaction. Furthermore, real-time en route information is in particular beneficial during the process leading to a steady state; it reduces the variance in travel time considerably. The paper concludes with a discussion on the Market potential of motorist information systems when commercially Marketed.
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the economics of motorist information systems revisited
Transport Reviews, 1994Co-Authors: Rhm Emmerink, Peter Nijkamp, Piet Rietveld, Kay W AxhausenAbstract:The literature on the implications of the implementation of motorist information systems is ambiguous, particularly with respect to the economic consequences. This paper aims to shed more light on the potential economic costs and benefits of these new technologies by reviewing and combining results obtained in the literature. Furthermore, future research directions, essential for an increased understanding of these systems, are pointed out. It is first argued that a motorist information system is not a normal economic good; the benefits accruing to the equipped road users are dependent on the level of Market Penetration. At most levels of Market Penetration a motorist information system is most likely to generate a positive external effect for non‐equipped motorists and a negative external effect for those already equipped. However, in terms of travel time, the equipped road users will outperform the non‐equipped ones. Next, the economic consequences of these peculiarities are identified, particularly wit...
Seiichi Shiga - One of the best experts on this subject based on the ideXlab platform.
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Scenario analysis of lightweight and electric-drive vehicle Market Penetration in the long-term and impact on the light-duty vehicle fleet
Applied Energy, 2017Co-Authors: Juan C. González Palencia, Yuki Otsuka, Mikiya Araki, Seiichi ShigaAbstract:Electric-drive vehicles, including hybrid electric vehicles, plug-in hybrid electric vehicles, battery electric vehicles, fuel cell electric vehicles and fuel cell hybrid electric vehicles, are emerging as less polluting alternatives to internal combustion engine vehicles. Therefore, it is important to assess their Penetration in the vehicle Market in the future. A ‘two-step’ approach is used to estimate the optimum Market Penetration of lightweight and electric-drive vehicles in the long-term and the impact on the light-duty vehicle fleet, focusing on Japan. First, an optimization model is used to estimate the vehicle Market composition in 2050. Then, a vehicle stock turnover model is used to estimate light-duty vehicle fleet energy and material consumption, CO2 emissions and cost. Internal combustion engine vehicles and hybrid electric vehicles dominate in the Base scenario. Fuel cell hybrid electric vehicles dominate when low cost is prioritized. Shift to battery electric vehicles occurs when low CO2 emissions are prioritized. CO2 emissions are reduced 56.9% between 2012 and 2050 in the Base scenario. Lightweight mini-sized battery electric vehicle diffusion has the largest CO2 emissions reductions, 87.3% compared to the 2050 baseline value; with the net cash flow peaking at 10.2 billion USD/year in 2035 and becoming negative after 2044.
