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Intelligent Transport Systems, IET

Issue 3 • Date September 2011

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Displaying Results 1 - 8 of 8
  • Route planning and user interface for an advanced intelligent transport system

    Publication Year: 2011 , Page(s): 149 - 158
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (437 KB)  

    The transport of hazardous materials can have a negative impact on human health and the environment quality; therefore it represents a relevant concern for each national economy of Europe. In Italy, the Apulia Region funded a research project to face this problem. In this framework, the authors proposed a flexible intelligent transport system (ITS) designed to work in many complex situations on the road network. This ITS uses artificial intelligence methods to implement route planning. Essentially, the system specifies a route for each vehicle by optimising a multi-objective function. The objectives, which are optimised, depend on the specific application and in this work they are related to the hazardous material transport impact reduction. This goal is achieved by implementing a negotiation process among intelligent agents. The system monitors the route followed by each vehicle and verifies if it coincides with the specified route. A key element of the ITS is a flexible on-board unit mounted on vehicles. It has a modular structure that allows for a variety of sensors to be connected, depending on the application. In this case, a variety of parameters, such as the vehicle speed, position, load balance and accelerations are analysed. Using that data the system identifies some characteristics, for example, the driver behaviour and hazardous vehicle operating conditions. In order to represent this information, the authors propose a multi-level metaphor-based graphic user interface (GUI). The first level of the interface provides a quickly understood view of the situation being monitored and it is oriented towards on-site first response and route monitoring operators. The second level provides more detailed information for incident managers and other operators. This interface has been evaluated using a human panel. Each volunteer has compiled a questionnaire after that he/she has used the interface for a 30-min session. The focus of this work is to present the approac- es adopted for route planning and the user interface. View full abstract»

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  • Simulation of requests in demand responsive transport systems

    Publication Year: 2011 , Page(s): 159 - 167
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (604 KB)  

    In a demand responsive transport system (DRTS), vehicles follow routes and timetables automatically scheduled by a travel dispatch centre to match the trip requests and to associate as many users as possible to the same vehicle, while guaranteeing the quality standards in terms of pickup/delivery time and travel duration. How efficient the system is in combining user requests on vehicles depends on the dispersion of travel demand, both space-wise and time-wise. This study describes and analyses a trips simulation method that aims at generating users' requests by recreating an actual demand structure of a study area divided into zones. It has been assumed that trip requests are sampled looking at specific features, such as the ability of attracting and generating trips assigned to the zones of the area, the information on minimum distance for trips and the time profile of the requests. Travel requests are then processed by a trip-planning tool, in order to assess the resources needed for the service operations (number of vehicles, travel times). The demand scenarios explored show the influence of the assumed criteria on the random minimum distance for DRTS trips, both on the characteristics of the generated demand and on the consequent trip-plans. View full abstract»

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  • Auto-adaptive and string stable strategy for intelligent cruise control

    Publication Year: 2011 , Page(s): 168 - 174
    Cited by:  Papers (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (699 KB)  

    This study completes the study of a longitudinal control strategy based on a non-linear acceleration profile model. The model is thoroughly defined by a set of two design parameters that make the control policy auto-adaptive. The control strategy is safe and Stop'consistent. The string stability property of the control policy is also analysed. Simulation results show that the control policy has a good string stability property with high string stability margin with respect to Pipes and Chandler's control strategy. View full abstract»

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  • Efficient transit planning framework using service composition and hierarchical aggregation schemes

    Publication Year: 2011 , Page(s): 175 - 182
    Cited by:  Papers (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (666 KB)  

    Modern advanced public transportation systems (APTSs) mostly maintain their own regional service information in a closed, non-sharable fashion in order to provide path planning service. When processing large-scope cross-regional paths which would require data from two or more APTSs, the service would be difficult or impossible since there is scarcely protocol for cross-system data exchanging. In addition, when planning a large scope trip, huge amount of services would take a long time to process. This work proposes NimbleTransit, an efficient web service-based transit planning framework using dynamic service composition and hierarchical aggregation schemes. In the framework, web service interfaces are specified for information exchanging, making it possible to integrally collect heterogeneous data from various APTSs and transportation enterprises. A dynamic service composition scheme is designed where the transit planning is performed between semantic and syntactic level to achieve scalability. The system prototype is implemented using web service-based data from Institute of Transportation in Taiwan, and the results showed that the proposed scheme is indeed more effective and scalable than other schemes. View full abstract»

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  • Route choice behaviour with pre-trip travel time information

    Publication Year: 2011 , Page(s): 183 - 189
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (272 KB)  

    The purpose of this study is to evaluate the potential benefits from real-time travel-time information provision by gaining insights into and better understanding of the factors affecting the route-choice behaviour of drivers possessing real-time pre-trip information. Both a field study and an in-laboratory experiment were conducted to obtain revealed preferences (RP) and stated preferences (SP) on route choice. The data collected from both experiments are inputs for a combined RP-SP route-choice model. The model also includes attitudinal factors describing drivers- personal characteristics. The results show that when experience seeking increases, individuals tend to prefer a route characterised by lower average but greater variance of travel time. Other results confirmed past studies showing that information has an impact on route-choice behaviour although compliance with received information decreases with recent experience. View full abstract»

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  • Eigen-based traffic sign recognition

    Publication Year: 2011 , Page(s): 190 - 196
    Cited by:  Papers (5)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1065 KB)  

    This study's purpose is to introduce eigen-based traffic sign recognition. This technique is based on invoking the principal component analysis (PCA) algorithm to choose the most effective components of traffic sign images to classify an unknown traffic sign. A set of weights are computed from the most effective eigen vectors of the traffic sign. By using the Euclidean distance, unknown traffic sign images are then classified. The approach was tested on two different databases of traffic sign's borders and speed limit pictograms that were extracted automatically from real-world images. A classification rate of 96.8 and 97.9' was achieved for these two databases. To check the robustness of this approach, non-traffic sign objects and occluded signs were invoked. A performance of 71' was achieved when occluded signs are used. When signs were rotated 10 degrees around their centre, the performance became 89' when traffic signs' outer shapes were used and for rotated speed limit pictograms the result was 80'. View full abstract»

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  • Integrating location tracking, traffic monitoring and semantics in a layered ITS architecture

    Publication Year: 2011 , Page(s): 197 - 206
    Cited by:  Papers (12)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (544 KB)  

    The new generation of Intelligent Transportation Systems (ITSs) should be able both to monitor in real-time the current user location and traffic conditions, and to access the heterogeneous data sources maintained by different organisations and useful for ITS applications. For this reason, a layered ITS architecture is proposed, which consists of a Wi-Fi communication layer for data exchange between users and control devices, a monitoring layer provided with fast algorithms to locate the users and to compute the travel times of a traffic network, an application layer to supervise the monitoring layer and to map the proprietary data sources into a standard format, i.e., the Resource Description Framework Schema (RDFS), and a semantic layer to retrieve and process RDFS data for supporting mobile applications. Implementation details are also given. In particular, a novel motion detection technique based on the Poisson distribution to evaluate the traffic parameters and a technique based on neural networks to locate the users are presented, whereas a suitable topology of the overall system to timely inform the mobile users is outlined. The architecture supports the internetworking of different monitoring and communication technologies to best fit a variety of users and use scenarios. View full abstract»

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  • Lateral control assistance in car driving: classification, review and future prospects

    Publication Year: 2011 , Page(s): 207 - 220
    Cited by:  Papers (5)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (310 KB)  

    This study puts forward a classification of driver lateral control assistance devices based on distinctions among several cooperative activities between the driver and the assistance devices. The proposed classification is based on prior work by Hoc, Young and Blosseville and Young, Stanton and Harris, who put forward related theoretical frameworks on human-machine cooperation with automation. The particular application here to lateral control allows for a human-centred categorisation of existing and potential (i.e. near-future) driver assistance devices. Four human-machine cooperation levels based on drivers- activities have been adopted. All of the proposed categories are reviewed in three steps. First, each device category is functionally defined. Next, the impact of the devices on driving behaviour is presented. A third part sums up the effectiveness of each assistance category, particularly with regard to accident data. The general conclusion synthesises the main insights for each human-machine category proposed and highlights a number of design recommendations. View full abstract»

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Aims & Scope

IET Intelligent Transport Systems is an interdisciplinary journal devoted to research into the practical applications of intelligent transport systems and infrastructures.

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