Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041289
Kyu-Ok Kim, L. Rilett
In recent years micro-simulation has become increasingly important in transportation system modeling. An on-going question is whether they adequately represent reality and whether adequate data exists with which to calibrate these models. Fortunately, over the last ten years there has been a rapid deployment of ITS technologies in most urban areas of North America. While the ITS are developed primarily for real-time traffic operations the data typically are archived and is available for traffic micro-simulation calibration. This paper presents a calibration approach for micro-simulation model which uses ITS data and is based on the sequential simplex algorithm. The test bed is a 23 kilometer section of Interstate 10 in Houston, Texas. Two micro-simulation models (CORSIM and TRANSIMS) were calibrated for the AM Peak for two different OD matrices. It was found that the simplex algorithm had better results then either the default values or a simple, manual calibration.
{"title":"Calibration of traffic micro-simulation models using the simplex algorithm","authors":"Kyu-Ok Kim, L. Rilett","doi":"10.1109/ITSC.2002.1041289","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041289","url":null,"abstract":"In recent years micro-simulation has become increasingly important in transportation system modeling. An on-going question is whether they adequately represent reality and whether adequate data exists with which to calibrate these models. Fortunately, over the last ten years there has been a rapid deployment of ITS technologies in most urban areas of North America. While the ITS are developed primarily for real-time traffic operations the data typically are archived and is available for traffic micro-simulation calibration. This paper presents a calibration approach for micro-simulation model which uses ITS data and is based on the sequential simplex algorithm. The test bed is a 23 kilometer section of Interstate 10 in Houston, Texas. Two micro-simulation models (CORSIM and TRANSIMS) were calibrated for the AM Peak for two different OD matrices. It was found that the simplex algorithm had better results then either the default values or a simple, manual calibration.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121742634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041220
Li Li, Feiyue Wang
This paper address the issue of generating an optimum trajectory for driving intelligent vehicles equipped with digital maps. The vehicle dynamic equation is incorporated into the design formulation for trajectory generation under several performance indices. A numerical procedure for solving the general optimum trajectory generation using a cell mapping method is developed. To demonstrate the effectiveness of the proposed solution, case studies for minimum time, energy, and jerk trajectories are conducted.
{"title":"Vehicle trajectory generation for optimal driving guidance","authors":"Li Li, Feiyue Wang","doi":"10.1109/ITSC.2002.1041220","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041220","url":null,"abstract":"This paper address the issue of generating an optimum trajectory for driving intelligent vehicles equipped with digital maps. The vehicle dynamic equation is incorporated into the design formulation for trajectory generation under several performance indices. A numerical procedure for solving the general optimum trajectory generation using a cell mapping method is developed. To demonstrate the effectiveness of the proposed solution, case studies for minimum time, energy, and jerk trajectories are conducted.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122482410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041200
D. Guo, Y. C. Hwang, Y. Adrian, C. Laugier
Background subtraction is an efficient technique in vision-based traffic monitoring, it segments the moving vehicle from the video sequences by comparing the incoming frame to the model of background scene. The presented work is a simple approach of adaptive background modeling in which the short term memory (STM) and long term memory (LTM) are introduced to construct the whole background memory. The color cue is used to build the model of pixel, u* and v* chrominancy components are carefully selected from modified L*u*v* color space, they are perceptually uniform such that color difference could be measured properly. Furthermore, object shadows are suppressed because the luminancy effects are removed. A simple prototype cell is defined to characterize the background scene by its 'circular influence field'. The match of prototype cell is measured by the Euclidean distance between the incoming pixel and prototype cell. The most recent prototype cells are stored in STM, they adapt quickly for the variations of background scene, but false detections easily occurs when the background has the high frequency variations. In LTM, prototype cells store the stable representation of the background scene, which are able to reduce the computation of STM updating. The adaptive learning procedure is carried out in both STM and LTM, it is able to deal with the scene changes. This background model is evaluated by the traffic video stream, experimental results show that the proposed approach is feasible for the traffic monitoring.
{"title":"Traffic monitoring using short-long term background memory","authors":"D. Guo, Y. C. Hwang, Y. Adrian, C. Laugier","doi":"10.1109/ITSC.2002.1041200","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041200","url":null,"abstract":"Background subtraction is an efficient technique in vision-based traffic monitoring, it segments the moving vehicle from the video sequences by comparing the incoming frame to the model of background scene. The presented work is a simple approach of adaptive background modeling in which the short term memory (STM) and long term memory (LTM) are introduced to construct the whole background memory. The color cue is used to build the model of pixel, u* and v* chrominancy components are carefully selected from modified L*u*v* color space, they are perceptually uniform such that color difference could be measured properly. Furthermore, object shadows are suppressed because the luminancy effects are removed. A simple prototype cell is defined to characterize the background scene by its 'circular influence field'. The match of prototype cell is measured by the Euclidean distance between the incoming pixel and prototype cell. The most recent prototype cells are stored in STM, they adapt quickly for the variations of background scene, but false detections easily occurs when the background has the high frequency variations. In LTM, prototype cells store the stable representation of the background scene, which are able to reduce the computation of STM updating. The adaptive learning procedure is carried out in both STM and LTM, it is able to deal with the scene changes. This background model is evaluated by the traffic video stream, experimental results show that the proposed approach is feasible for the traffic monitoring.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127192476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041312
Long Chen, Feiyue Wang
Because the neuro-fuzzy system (NFS) combines the learning capability of neural networks and the decision structure of fuzzy inference systems, it is very useful in the modeling, control, and forecasting of complex systems such as traffic systems. This paper proposes a form of neuro-fuzzy systems (NFS) and applies it to forecast short-term traffic flows. Different learning algorithms for the NFS have been tested and evaluated using actual traffic data collected from the Loop 3 Freeway in Beijing, China. These test results indicate that the NFS based approach is an effective method for short-tern traffic flow forecasting. To demonstrate the advantage of the proposed approach, a comparison with a typical neural network based approach has been made.
{"title":"A neuro-fuzzy system approach for forecasting short-term freeway traffic flows","authors":"Long Chen, Feiyue Wang","doi":"10.1109/ITSC.2002.1041312","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041312","url":null,"abstract":"Because the neuro-fuzzy system (NFS) combines the learning capability of neural networks and the decision structure of fuzzy inference systems, it is very useful in the modeling, control, and forecasting of complex systems such as traffic systems. This paper proposes a form of neuro-fuzzy systems (NFS) and applies it to forecast short-term traffic flows. Different learning algorithms for the NFS have been tested and evaluated using actual traffic data collected from the Loop 3 Freeway in Beijing, China. These test results indicate that the NFS based approach is an effective method for short-tern traffic flow forecasting. To demonstrate the advantage of the proposed approach, a comparison with a typical neural network based approach has been made.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133715014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041303
A. Iera, A. Modafferi, G. Musolino, A. Vitetta
Several researches have been conducted on real-time traffic monitoring topic and relevant applications in the same field have been developed in the last years. Interesting results have been obtained from the integrated utilization of different technologies (traffic monitoring tools, information transmission systems, etc.). The paper reports on a research activity in progress concerning the implementation of an integrated system for real-time traffic monitoring, through video sensors and inductive loops, and their real-time transmission from a survey station to a remote operational lab. The survey station has been implemented in an urban road of Reggio Calabria (Italy), where a high number of buses and private vehicles interact with pedestrian flow. The first results concern the system test and evaluation in order to develop a reliable survey system-prototype for urban roads; the acquisition of an extended data-base for different traffic and environmental conditions.
{"title":"An experimental station for real-time traffic monitoring on a urban road","authors":"A. Iera, A. Modafferi, G. Musolino, A. Vitetta","doi":"10.1109/ITSC.2002.1041303","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041303","url":null,"abstract":"Several researches have been conducted on real-time traffic monitoring topic and relevant applications in the same field have been developed in the last years. Interesting results have been obtained from the integrated utilization of different technologies (traffic monitoring tools, information transmission systems, etc.). The paper reports on a research activity in progress concerning the implementation of an integrated system for real-time traffic monitoring, through video sensors and inductive loops, and their real-time transmission from a survey station to a remote operational lab. The survey station has been implemented in an urban road of Reggio Calabria (Italy), where a high number of buses and private vehicles interact with pedestrian flow. The first results concern the system test and evaluation in order to develop a reliable survey system-prototype for urban roads; the acquisition of an extended data-base for different traffic and environmental conditions.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"52 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134063142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041337
M. Adelantado, C. Damioli, A. Dedieu
To operate an airport at its maximum capacity, especially under poor weather conditions, several regulations, equipment or computer-based assistance systems are currently under evaluation. The French Aeronautics and Space Research Center (ONERA) is carrying out a federative R&D project to propose solutions which enhance traffic management of future airports while maintaining safety. One goal of this initiative is to evaluate through simulation several levels of automation, assistance equipment, and tools for controllers, To achieve this goal, a reusable High Level Architecture kernel federation has been designed. In this paper, we describe the architecture of this federation and discuss how it can be easily reused to integrate existing simulators of airport traffic assistance or automation systems. The HLA federation has been written in C++ and Java languages, and uses the RTI NG freely available from the Defense Modeling and Simulation Office (DMSO).
{"title":"A reusable HLA federation for simulation of airport traffic assistance/automation systems","authors":"M. Adelantado, C. Damioli, A. Dedieu","doi":"10.1109/ITSC.2002.1041337","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041337","url":null,"abstract":"To operate an airport at its maximum capacity, especially under poor weather conditions, several regulations, equipment or computer-based assistance systems are currently under evaluation. The French Aeronautics and Space Research Center (ONERA) is carrying out a federative R&D project to propose solutions which enhance traffic management of future airports while maintaining safety. One goal of this initiative is to evaluate through simulation several levels of automation, assistance equipment, and tools for controllers, To achieve this goal, a reusable High Level Architecture kernel federation has been designed. In this paper, we describe the architecture of this federation and discuss how it can be easily reused to integrate existing simulators of airport traffic assistance or automation systems. The HLA federation has been written in C++ and Java languages, and uses the RTI NG freely available from the Defense Modeling and Simulation Office (DMSO).","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134353162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041245
T. Kitamura, T. Nagaosa, T. Hasegawa, K. Mori, H. Kobayashi
This paper describes vehicle position accuracy exchanged among vehicles in the V-PEACE (Vehicle Position Environment Acquisition and Communication Evolution) scheme. Vehicles in the V-PEACE scheme can exchange position information with each other by broadcasting pulses on TDM (Time Division Multiplex) frames. The pulse is transmitted with unique timing determined by the vehicle's position on the road. A vehicle that received the pulse can distinguish the position and the length of the transmitting vehicle on the road from the position and the width of the pulse on the TDM frame. In this paper, the authors examine the accuracy of the received information when exchanging position information pulses among vehicles on the road. A performance evaluation is carried out concerning the accuracy of vehicle position information transmitted under the multipath environment with consideration of reflection on the road, other vehicles and roadside wall surface via computer simulation.
本文描述了V-PEACE (vehicle position Environment Acquisition and Communication Evolution，车辆位置环境获取与通信演化)方案中车辆之间的位置精度交换。V-PEACE方案中的车辆可以通过在时分复用(TDM)帧上广播脉冲来交换彼此的位置信息。脉冲的传输时间由车辆在道路上的位置决定。接收脉冲的车辆可以从TDM帧上脉冲的位置和宽度区分出发射车辆在道路上的位置和长度。在本文中，作者检验了在道路上的车辆之间交换位置信息脉冲时接收信息的准确性。通过计算机仿真对多径环境下传输的车辆位置信息的准确性进行了性能评价，同时考虑了对道路、其他车辆和路边壁面的反射。
{"title":"Vehicle position accuracy exchanged among vehicles in the V-PEACE scheme","authors":"T. Kitamura, T. Nagaosa, T. Hasegawa, K. Mori, H. Kobayashi","doi":"10.1109/ITSC.2002.1041245","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041245","url":null,"abstract":"This paper describes vehicle position accuracy exchanged among vehicles in the V-PEACE (Vehicle Position Environment Acquisition and Communication Evolution) scheme. Vehicles in the V-PEACE scheme can exchange position information with each other by broadcasting pulses on TDM (Time Division Multiplex) frames. The pulse is transmitted with unique timing determined by the vehicle's position on the road. A vehicle that received the pulse can distinguish the position and the length of the transmitting vehicle on the road from the position and the width of the pulse on the TDM frame. In this paper, the authors examine the accuracy of the received information when exchanging position information pulses among vehicles on the road. A performance evaluation is carried out concerning the accuracy of vehicle position information transmitted under the multipath environment with consideration of reflection on the road, other vehicles and roadside wall surface via computer simulation.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134288241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041215
H. Phtsuka, L. Vlacic
In this paper a vehicle longitudinal model targeted towards tow velocity adaptive cruise control systems Is presented through a review of conventional models. The vehicle model obtained has two inputs, namely the engine input and the brake input. Also it is described by the composite of the power-train system model, the brake system model and the drive-train model. The response of the proposed model is examined through numerical simulation.
{"title":"Stop and go vehicle longitudinal model","authors":"H. Phtsuka, L. Vlacic","doi":"10.1109/ITSC.2002.1041215","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041215","url":null,"abstract":"In this paper a vehicle longitudinal model targeted towards tow velocity adaptive cruise control systems Is presented through a review of conventional models. The vehicle model obtained has two inputs, namely the engine input and the brake input. Also it is described by the composite of the power-train system model, the brake system model and the drive-train model. The response of the proposed model is examined through numerical simulation.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115481230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041210
J.R. Zhang, S.J. Xu
This paper studies the observer design for automatic steering. The coupled longitudinal and lateral motion is considered. A nonlinear transformation is used to transfer the system into an affinely nonlinear system. A nonlinear observer is proposed to estimate the yaw rate of vehicle. Simulation results show that the designed observer is effective.
{"title":"Nonlinear observer design for automatic steering of vehicles","authors":"J.R. Zhang, S.J. Xu","doi":"10.1109/ITSC.2002.1041210","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041210","url":null,"abstract":"This paper studies the observer design for automatic steering. The coupled longitudinal and lateral motion is considered. A nonlinear transformation is used to transfer the system into an affinely nonlinear system. A nonlinear observer is proposed to estimate the yaw rate of vehicle. Simulation results show that the designed observer is effective.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115884508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-09-03DOI: 10.1109/ITSC.2002.1041227
T. Kato, A. Kobayasi, H. Hase, M. Yoneda
In this paper, we present a road guide sign recognition method the driver support system in intelligent transportation systems (ITS). Generally, on a guide sign, there are arrows representing directions and characters representing destinations and distances. First, arrows are detected using their shape characteristics. Next, the sign is classified using the number of arrow objects and the number of arrowheads. Then, the characters on the sign are assigned to their corresponding arrowheads by segmenting the sign using arrowhead positions. Finally, after the character recognition process, we obtain the information of directions, destinations and distances. We tested 65 images of zoomed in signs. 154 arrowheads on these signs were detected completely. In 62 images, characters were assigned to corresponding arrowheads successfully. Hence, our method is effective for sign image understanding.
{"title":"An experimental consideration for road guide sign understanding in ITS","authors":"T. Kato, A. Kobayasi, H. Hase, M. Yoneda","doi":"10.1109/ITSC.2002.1041227","DOIUrl":"https://doi.org/10.1109/ITSC.2002.1041227","url":null,"abstract":"In this paper, we present a road guide sign recognition method the driver support system in intelligent transportation systems (ITS). Generally, on a guide sign, there are arrows representing directions and characters representing destinations and distances. First, arrows are detected using their shape characteristics. Next, the sign is classified using the number of arrow objects and the number of arrowheads. Then, the characters on the sign are assigned to their corresponding arrowheads by segmenting the sign using arrowhead positions. Finally, after the character recognition process, we obtain the information of directions, destinations and distances. We tested 65 images of zoomed in signs. 154 arrowheads on these signs were detected completely. In 62 images, characters were assigned to corresponding arrowheads successfully. Hence, our method is effective for sign image understanding.","PeriodicalId":365722,"journal":{"name":"Proceedings. The IEEE 5th International Conference on Intelligent Transportation Systems","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116118637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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