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  • 期刊名称：

    Intelligent Transportation Systems, IEEE Transactions on

  • 中文名称： 智能交通系统，IEEE事务
  • 刊频：
  • ISSN： 1524-9050
  • 出版社： -
  • 简介：

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  • 1.

    【24hr】Efficient Lane Detection Based on Spatiotemporal Images

    包量

    机译 基于时空图像的高效车道检测
    摘要：In this paper, we propose an efficient method for reliably detecting road lanes based on spatiotemporal images. In an aligned spatiotemporal image generated by accumulating the pixels on a scanline along the time axis and aligning consecutive scanlines, the trajectory of the lane points appears smooth and forms a straight line. The aligned spatiotemporal image is binarized, and two dominant parallel straight lines resulting from the temporal consistency of lane width on a given scanline are detected using a Hough transform, reducing alignment errors. The left and right lane points are then detected near the intersections of the straight lines and the current scanline. Our spatiotemporal domain approach is more robust missing or occluded lanes than existing frame-based approaches. Furthermore, the experimental results show not only computation times reduced to as little as one-third but also a slightly improved rate of detection.
  • 2.

    【24hr】A Novel Approach for Improved Vehicular Positioning Using Cooperative Map Matching and Dynamic Base Station DGPS Concept

    包量

    机译 利用协作地图匹配和动态基站DGPS概念改进车辆定位的新方法
    摘要：In this paper, a novel approach for improving vehicular positioning is presented. This method is based on the cooperation of the vehicles by communicating their measured information about their position. This method consists of two steps. In the first step, we introduce our cooperative map matching method. This map matching method uses the V2V communication in a vehicular ad hoc network (VANET) to exchange global positioning system (GPS) information between vehicles. Having a precise road map, vehicles can apply the road constraints of other vehicles in their own map matching process and acquire a significant improvement in their positioning. After that, we have proposed the concept of a dynamic base station DGPS (DDGPS), which is used by vehicles in the second step to generate and broadcast the GPS pseudorange corrections that can be used by newly arrived vehicles to improve their positioning. The DDGPS is a decentralized cooperative method that aims to improve the GPS positioning by estimating and compensating the common error in GPS pseudorange measurements. It can be seen as an extension of DGPS where the base stations are not necessarily static with an exact known position. In the DDGPS method, the pseudorange corrections are estimated based on the receiver's belief on its positioning and its uncertainty and then broadcasted to other GPS receivers. The performance of the proposed algorithm has been verified with simulations in several realistic scenarios.
  • 3.

    【24hr】Modeling Drivers' Dynamic Decision-Making Behavior During the Phase Transition Period: An Analytical Approach Based on Hidden Markov Model Theory

    包量

    机译 过渡阶段驾驶员动态决策行为建模：一种基于隐马尔可夫模型理论的分析方法
    摘要：A flashing green indication of 3 s followed by a yellow indication of 3s is commonly applied to end a green phase at signalized intersections in many Chinese cities. This paper proposes an analytical approach based on the hidden Markov model theory to interpret the dynamic decision-making process of drivers during the phase transition period at high-speed signalized intersections. In the proposed model, the hidden states are the unobservable time-dependent decisions of drivers concerning whether to stop or pass, and the observable states are the instantaneous vehicle speeds and acceleration/deceleration rates that are obtained from the high-resolution vehicle trajectory data. The data were collected by videotaping four typical high-speed intersection approaches with a speed limit of 80 km/h in Shanghai. Eventually, 698 vehicle trajectories including 179 trucks and 519 passenger cars were extracted from the videos and used for model estimation and validation. It was found that the proposed model could predict stop–pass decisions with very high accuracy and revealed that approximately 50% of drivers used a two-step decision-making process. In addition, a large percentage of decision changes occurred 0–1.2 s after the onset of yellow, which is based on a driver's perceived environment. The important implications of the proposed model and the findings are also discussed in this paper.
  • 4.

    【24hr】Development and Testing of a 3G/LTE Adaptive Data Collection System in Vehicular Networks

    包量

    机译 车载网络中3G / LTE自适应数据收集系统的开发和测试
    摘要：Vehicular ad hoc networks (VANETs) are a special case of mobile ad hoc networks (MANETs). The distinctive characteristics of VANETs include high-speed vehicular nodes and significant variability in node density. Collecting data from VANETs is important in monitoring, controlling, and managing road traffic. However, efficient collection of the needed data is challenging because vehicles are continuously moving and generating a significant amount of events and data. The focus of this paper is on vehicle data collection using 3G/LTE. Initially, a comparison of proactive and reactive data collection schemes is conducted using simulation. The results show that proactive schemes produce the lowest delay and bandwidth usage but the highest loss ratio. To efficiently use the available bandwidth, an adaptive data collection scheme is developed and described. This adaptive data collection scheme is based on a proactive scheme using variable polling periods depending on the vehicle positions in the network and travel time to provide accurate traffic and travel time information to the Traffic Management Center (TMC). Simulation results, using taxi traces in Qatar, show that the proposed algorithm consumes an acceptable amount of megabytes ( 31 MB) per month when the basic polling interval is set to 10 s. Furthermore, traffic simulation results demonstrate that the proposed scheme has a minimum impact on delay and travel time estimates (relative error less than 2.5%), but can produce significant degradations in fuel consumption and emission estimates if computations are made at the TMC (relative error greater than 28% and 65%, respectively). These errors can be eliminated if computations are done on the vehicle.
  • 5.

    【24hr】Integrated Determination of Network Origin–Destination Trip Matrix and Heterogeneous Sensor Selection and Location Strategy

    包量

    机译 网络起点-目的地行程矩阵和异构传感器选择与定位策略的综合确定
    摘要：This paper proposes a two-stage optimization model to determine the origin–destination (O–D) trip matrix and the heterogeneous sensor deployment strategy in an integrated manner for a vehicular traffic network using sensor information from active (camera-based license plate recognition) and passive (vehicle detector) sensors. The first stage solves the heterogeneous sensor selection and location problem to determine the optimal sensor deployment strategy, in terms of the selection of the numbers of the two sensor types and their installation locations, to maximize the traffic information available for the O–D matrix estimation problem. The traffic information includes the observed link flow, path trajectory, and path coverage information. The second stage leverages this traffic information to determine the network O–D matrix that minimizes the error between the observed and estimated traffic flows (link, O–D, and/or path). Correspondingly, two network O–D matrix estimation models are proposed where the link-based model incorporates the flow conservation rule between O–D and link flows and uses the link-node incidence matrix, and the path-based model assumes a given link-path incidence matrix. An iterative solution procedure is designed to determine the network O–D matrix and link flow estimates. Results from numerical experiments suggest that the path-based model outperforms the link-based model in the estimation of network O–D matrices. The relative contributions of combinations of the two sensor types to the network O–D matrix estimation problem are also analyzed. They suggest that active sensors provide valuable path information to solve the O–D matrix estimation problem, but at the cost of a significantly higher unit price. The study results have key implications for heterogeneous sensor selection and location strategies.
  • 6.

    【24hr】Editorial

    包量

    机译 社论
    • 作者：Ioannou Petros;
    • 刊名：Intelligent Transportation Systems, IEEE Transactions on
    • 2016年第1期
    摘要：
  • 7.

    【24hr】Sequential FDIA for Autonomous Integrity Monitoring of Navigation Maps on Board Vehicles

    包量

    机译 顺序FDIA用于车载导航地图的自主完整性监控
    摘要：This paper addresses the problem of fault detection, isolation, and adaptation (FDIA) in navigation systems on board passenger vehicles. The aim is to prevent malfunctions in systems such as advanced driving assistance systems and autonomous driving functions that use data provided by the navigation system. The integrity of the estimation of the vehicle position provided by the navigation system is continuously monitored and assessed. The proposed approach uses an additional estimate of vehicle position that is independent of the navigation system and based on data from standard vehicle sensors. First, fault detection consists in comparing the two estimates using a sequential statistical test to detect discrepancies despite the presence of noise. Second, fault isolation and adaptation is introduced to identify faulty estimates and to provide a correction where necessary. The FDIA framework presented here utilizes repeated trips along the same roads as a source of redundancy. Relevant properties of this formalism are given and verified experimentally using an equipped vehicle in rural and urban conditions and with various map faults. Results show that sequential FDIA performed well, even in difficult GNSS conditions.
  • 8.

    【24hr】Information-Theoretic Location Verification System With Directional Antennas for Vehicular Networks

    包量

    机译 车载网络用定向天线的信息理论位置验证系统
    摘要：In this paper, we consider a vehicular network and propose the application of directional antennas to a recently proposed information-theoretic location verification system (LVS), aiming at increasing the system capability in correctly detecting malicious nodes. In the proposed LVS with directional antennas (LVS-DA), we adopt a more realistic dual-slope large-scale fading model that is suitable to vehicular networks. The performance of the proposed scheme is evaluated analytically for some specific number of directional antennas and confirmed by numerical results, showing that the proposed LVS-DA scheme is capable of considerably increasing the system capability in detecting malicious nodes when compared with other recently proposed schemes, under different scenarios.
  • 9.

    【24hr】Emergency Traffic-Light Control System Design for Intersections Subject to Accidents

    包量

    机译 事故路口紧急交通灯控制系统设计
    摘要：Petri nets (PNs) are well utilized as a visual and mathematical formalism to model discrete-event systems. This paper uses deterministic and stochastic PNs to design an emergency traffic-light control system for intersections providing emergency response to deal with accidents. According to blocked crossing sections, as depicted by dynamic PN models, the corresponding emergency traffic-light strategies are designed to ensure the safety of an intersection. The cooperation among traffic lights/facilities at those affected intersections and roads is illustrated. For the upstream neighboring intersections, a traffic-signal-based emergency control policy is designed to help prevent accident-induced large-scale congestion. Deadlock recovery, livelock prevention, and conflict resolution strategies are developed. We adopt a reachability analysis method to verify the constructed model. To our knowledge, this is the first paper that employs PNs to model and design a real-time traffic emergency system for intersections facing accidents. It can be used to improve the state of the art in real-time traffic accident management and traffic safety at intersections.
  • 10.

    【24hr】Bluetooth Traffic Monitoring Systems for Travel Time Estimation on Freeways

    包量

    机译 蓝牙交通监控系统，用于高速公路上的行驶时间估计
    摘要：A Bluetooth traffic monitoring system (BTMS) is capable of identifying vehicles and estimate their travel time (TT) in a route. This information is key for intelligent transportation systems. Although BTMSs are currently deployed in several cities throughout the world, there is no formal methodology for the TT estimation they generate. In this paper, we first analyze the specific features of the Bluetooth technology that affect the TT estimation. In particular, we study the reliability of the measurements, the representativeness of the estimates, and the issues regarding multiple detections and outliers. Based on this knowledge, we propose a comprehensive methodology for the TT estimation that considers information from vehicles. We filter these vehicles through a simple process that uses the available dedicated inquiry access code. In order to illustrate our proposal, we performed an experiment deploying commercial Bluetooth detectors on a freeway under real traffic conditions. The resulting BTMS provided highly reliable TT estimations with a 5-min resolution.
  • 11.

    【24hr】Integrated Predictive Control of Freeway Networks Using the Extended Link Transmission Model

    包量

    机译 使用扩展链接传输模型的高速公路网络集成预测控制
    摘要：In this paper, the recently developed link transmission model (LTM) is utilized in an online hybrid model-based predictive control (MPC) framework. The model is extended to include the effects of ramp metering and variable speed limits. Next, an integrated freeway traffic control based on the new model is presented in order to minimize the total time spent in the network. The integrated scheme has the capability of controlling large-scale freeway networks in real time as the model is computationally efficient, and it is yet accurate enough for our control purposes. In addition, the extended model is reformulated as a system of linear inequalities with mixed binary and real variables. The reformulated model along with the linearized total travel time objective function establish a mixed-integer linear optimization problem that is more tractable and even faster than the original optimization problem integrated in the MPC scheme. Finally, to investigate the performance of the proposed approaches (nonlinear MPC and the mixed-integer linear counterpart), a freeway network layout based on the Leuven Corridor in Belgium is selected. The extended LTM is calibrated for this network using microsimulation data and then is used for prediction and control of the large network. Microsimulation results show that the proposed methods are able to efficiently improve the total travel time.
  • 12.

    【24hr】Spatial-Related Traffic Sign Inspection for Inventory Purposes Using Mobile Laser Scanning Data

    包量

    机译 使用移动激光扫描数据进行与空间相关的交通标志检查，以进行清单清点
    摘要：This paper presents a spatial-related traffic sign inspection process for sign type, position, and placement using mobile laser scanning (MLS) data acquired by a RIEGL VMX-450 system and presents its potential for traffic sign inventory applications. First, the paper describes an algorithm for traffic sign detection in complicated road scenes based on the retroreflectivity properties of traffic signs in MLS point clouds. Then, a point cloud-to-image registration process is proposed to project the traffic sign point clouds onto a 2-D image plane. Third, based on the extracted traffic sign points, we propose a traffic sign position and placement inspection process by creating geospatial relations between the traffic signs and road environment. For further inventory applications, we acquire several spatial-related inventory measurements. Finally, a traffic sign recognition process is conducted to assign sign type. With the acquired sign type, position, and placement data, a spatial-associated sign network is built. Experimental results indicate satisfactory performance of the proposed detection, recognition, position, and placement inspection algorithms. The experimental results also prove the potential of MLS data for automatic traffic sign inventory applications.
  • 13.

    【24hr】Stability and Scalability of Homogeneous Vehicular Platoon: Study on the Influence of Information Flow Topologies

    包量

    机译 均质车辆排的稳定性和可伸缩性：信息流拓扑的影响研究
    摘要：In addition to decentralized controllers, the information flow among vehicles can significantly affect the dynamics of a platoon. This paper studies the influence of information flow topology on the internal stability and scalability of homogeneous vehicular platoons moving in a rigid formation. A linearized vehicle longitudinal dynamic model is derived using the exact feedback linearization technique, which accommodates the inertial delay of powertrain dynamics. Directed graphs are adopted to describe different types of allowable information flow interconnecting vehicles, including both radar-based sensors and vehicle-to-vehicle (V2V) communications. Under linear feedback controllers, a unified internal stability theorem is proved by using the algebraic graph theory and Routh–Hurwitz stability criterion. The theorem explicitly establishes the stabilizing thresholds of linear controller gains for platoons, under a large class of different information flow topologies. Using matrix eigenvalue analysis, the scalability is investigated for platoons under two typical information flow topologies, i.e., 1) the stability margin of platoon decays to zero as for bidirectional topology; and 2) the stability margin is always bounded and independent of the platoon size for bidirectional-leader topology. Numerical simulations are used to illustrate the results.
  • 14.

    【24hr】Analysis of Taxi Drivers' Behaviors Within a Battle Between Two Taxi Apps

    包量

    机译 两个出租车应用之间的战斗中出租车司机的行为分析
    摘要：A battle between two Chinese taxi booking mobile apps, namely, Didi and Kuaidadi, had recently occurred in early 2014. These two apps, which are backed by Internet giants Tencent and Alipay, gave promotion fees to taxi drivers for each deal made and also allowed each taxi passenger to save some money, when a customer had taken a taxi through the app and paid the fare through the mobile payment method. As expected, the taxi service pattern had been greatly changed during this battle. To address the debates on social justice, equity, and improvements of taxi service, we collect 37-day trip data of over 9000 taxis in Beijing to study the influence of this pattern change. In the first 18 days, the battle had not occurred and in the remaining 19 days, the battle is white-hot. We quantitatively demonstrate how several important service indices (e.g., the traveling distances and idle time lengths) of taxi drivers had been changed. The spatial–temporal traveling patterns of taxis are then studied. Based on comprehensive analysis, the benefits and drawbacks brought by money promotion are finally discussed. The obtained results indicate that productively employing big data can help answer some important questions attracting the interest of the whole society.
  • 15.

    【24hr】Audio Surveillance of Roads: A System for Detecting Anomalous Sounds

    包量

    机译 道路音频监视：异常声音检测系统
    摘要：In the last decades, several systems based on video analysis have been proposed for automatically detecting accidents on roads to ensure a quick intervention of emergency teams. However, in some situations, the visual information is not sufficient or sufficiently reliable, whereas the use of microphones and audio event detectors can significantly improve the overall reliability of surveillance systems. In this paper, we propose a novel method for detecting road accidents by analyzing audio streams to identify hazardous situations such as tire skidding and car crashes. Our method is based on a two-layer representation of an audio stream: at a low level, the system extracts a set of features that is able to capture the discriminant properties of the events of interest, and at a high level, a representation based on a bag-of-words approach is then exploited in order to detect both short and sustained events. The deployment architecture for using the system in real environments is discussed, together with an experimental analysis carried out on a data set made publicly available for benchmarking purposes. The obtained results confirm the effectiveness of the proposed approach.
  • 16.

    【24hr】Road Slope Aided Vehicle Position Estimation System Based on Sensor Fusion of GPS and Automotive Onboard Sensors

    包量

    机译 基于GPS和汽车车载传感器融合的道路边坡辅助车辆位置估计系统。
    摘要：This paper proposes a road slope aided position estimation algorithm based on the fusion of GPS data with information from automotive onboard sensors. Many previous studies for position estimation did not consider the effect of road slope, although many sloped roads are existing. In order to analyze the influence of road slope on position estimation, theoretical proof and simulation are performed. Based on this analysis, a road slope aided position estimation algorithm is presented, which includes a vehicle motion model that can compensate for the effect of the road slope. This algorithm can estimate the position and road slope simultaneously. Furthermore, by compensating for the error due to the road slope, the algorithm can improve the position estimation accuracy and reliability. The estimation algorithm in this paper is implemented and evaluated using automotive onboard sensors and embedded system; therefore, additional motion sensors and high-performance computational units are not necessary. The experimental results show that the accuracy and reliability of the road slope aided position algorithm provide superior performance compared with a planar vehicle model-based position estimation algorithm in mountainous terrain.
  • 17.

    【24hr】A Blind-Zone Detection Method Using a Rear-Mounted Fisheye Camera With Combination of Vehicle Detection Methods

    包量

    机译 后装式鱼眼镜头与车辆检测方法相结合的盲区检测方法
    摘要：This paper proposes a novel approach for detecting and tracking vehicles to the rear and in the blind zone of a vehicle, using a single rear-mounted fisheye camera and multiple detection algorithms. A maneuver that is a significant cause of accidents involves a target vehicle approaching the host vehicle from the rear and overtaking into the adjacent lane. As the overtaking vehicle moves toward the edge of the image and into the blind zone, the view of the vehicle gradually changes from a front view to a side view. Furthermore, the effects of fisheye distortion are at their most pronounced toward the extremities of the image, rendering detection of a target vehicle entering the blind zone even more difficult. The proposed system employs an AdaBoost classifier at distances of 10–40 m between the host and target vehicles. For detection at short distances where the view of a target vehicle has changed to a side view and the AdaBoost classifier is less effective, identification of vehicle wheels is proposed. Two methods of wheel detection are employed: at distances between 5 and 15 m, a novel algorithm entitled wheel arch contour detection (WACD) is presented, and for distances less than 5 m, Hough circle detection provides reliable wheel detection. A testing framework is also presented, which categorizes detection performance as a function of distance between host and target vehicles. Experimental results indicate that the proposed method results in a detection rate of greater than 93% in the critical range (blind zone) of the host.
  • 18.

    【24hr】A Survey on Energy-Efficient Train Operation for Urban Rail Transit

    包量

    机译 城市轨道交通列车节能运行调查
    摘要：Due to rising energy prices and environmental concerns, the energy efficiency of urban rail transit has attracted much attention from both researchers and practitioners in recent years. Timetable optimization and energy-efficient driving, as two mainly used train operation methods in relation to the tractive energy saving, make major contributions in reducing the energy consumption that has been studied for a long time. Generally speaking, timetable optimization synchronizes the accelerating and braking actions of trains to maximize the utilization of regenerative energy, and energy-efficient driving optimizes the speed profile at each section to minimize the tractive energy consumption. In this paper, we present a fully comprehensive survey on energy-efficient train operation for urban rail transit. First, a general energy consumption distribution of urban rail trains is described. Second, the current literature on timetable optimization and energy-efficient driving is reviewed. Finally, according to the review work, it is concluded that the integrated optimization method jointly optimizing the timetable and speed profile has become a new tendency and ought to be paid more attention in future research.
  • 19.

    【24hr】Probabilistic Inference for Occluded and Multiview On-road Vehicle Detection

    包量

    机译 闭塞和多视图道路车辆检测的概率推理
    摘要：Visual-based approaches have been extensively studied for on-road vehicle detection; however, it faces great challenges as the visual appearance of a vehicle may greatly change across different viewpoints and as a partial observation sometimes happens due to occlusions from infrastructure or scene dynamics and/or a limited camera vision field. This paper presents a visual-based on-road vehicle detection algorithm for a multilane traffic scene. A probabilistic inference framework based on part models is proposed to overcome the challenges from a multiview and partial observation. Geometric models are learned for each dominant viewpoint to describe the configuration of vehicle parts and their spatial relations in probabilistic representations. Viewpoint maps are generated based on the knowledge of the road structure and driving patterns, which provide a prediction of the viewpoints of a vehicle whenever it happens at a certain location. Extensive experiments are conducted using an onboard camera on multilane motor ways in Beijing. A large-scale data set that contains more than 30 000 labeled ground truths for both fully and partially observed vehicles in different viewpoints across various traffic density scenes is developed. The data set will be opened to the society together with this publication.
  • 20.

    【24hr】Detecting Road Events Using Distributed Data Fusion: Experimental Evaluation for the Icy Roads Case

    包量

    机译 使用分布式数据融合检测道路事件：冰冷道路案例的实验评估
    摘要：One of the main ideas in the area of intelligent transport systems is to use all possible information coming from vehicles and infrastructure, in order to make the system “smarter” and avoid potentially dangerous situations—collisions, accidents, bottleneck, etc. However, data are sometimes unreliable due to source and communication network quality, leading vehicles or even the whole system to wrong decisions. We present a generic method for detecting dangerous events on the road. To support unreliable data sources, it uses distributed data fusion. Moreover, to deal with network failures, it relies on a self-stabilizing generic distributed algorithm. Our method mixes measurements obtained from vehicle onboard sensors, as well as wireless sensors placed close to the road and connected to road side units. Each vehicle computes how confident it is about a potential dangerous event using both local and remote data. To evaluate our approach, we implemented it using a specific hardware and software platform. Moreover, we instantiated a simple, yet efficient application to detect icy roads, based on temperature measurements. Thanks to both in-lab and actual on-the-road experiments, we demonstrate the possibility to deduce proper results from unreliable data and, consequently, the correctness and usefulness of our approach.
  • 21.

    【24hr】Geovisualization of Archived ITS Data-Case Studies

    包量

    机译 ITS存档案例研究的地理可视化
    摘要：Although transportation data have a spatial component by nature, this component generally has not been fully utilized when it comes to intelligent transportation system (ITS) archived data. This paper demonstrates the use of geographic information system (GIS) to spatially visualize and analyze transportation management center (TMC)-related performance measures derived from archived ITS data from a traffic management center in Texas, namely, San Antonio's TransGuide. The paper discusses three case studies. The first case study involved a performance evaluation of an automatic incident detection algorithm deployed by many traffic management centers after a few years of implementation in the field. The overall detection rate was found to be about 20%, and the overall false rate was about 0.005%. The second case study summarizes work completed to address quality control issues associated with a very large archived ITS data set composed of some 3.4 billion 20-s loop detector data records. There were some 1.6 billion (about 48%) speed, volume, and occupancy records that had a quality control flag. Approximately 1.5 billion flagged records were “valid” records, and the remaining 126 million (about 3.7%) flagged records were “abnormal” records. In the third case study, the researchers evaluated the data completeness both at the aggregate level (by server) and at a more detailed individual detector level. At the server level, the completeness rate varied from 95% to 100%. At the individual detector level, the analysis showed that, on average, the completeness rate for all detectors was about 80%. The researchers utilized GIS to prepare maps showing the spatial distribution of incident detection rate, false alarm rate, quality control flags, and data completeness rate. It is worth mentioning that all of the analysis was performed at a detailed segment-by-segment level, which is by itself a unique - ddition. The researchers recommend implementing the demonstrated spatial analysis of the archived ITS data. This will allow TMC officials to identify spots with any abnormal behavior, whether it is at the corridor level or even at the segment level.
  • 22.

    【24hr】Passenger Journey Destination Estimation From Automated Fare Collection System Data Using Spatial Validation

    包量

    机译 使用空间验证从自动票价收集系统数据中估算旅客旅程目的地
    摘要：A methodology for estimating the destination of passenger journeys from automated fare collection (AFC) system data is described. It proposes new spatial validation features to increase the accuracy of destination inference results and to verify key assumptions present in previous origin–destination estimation literature. The methodology applies to entry-only system configurations combined with distance-based fare structures, and it aims to enhance raw AFC system data with the destination of individual journeys. This paper describes an algorithm developed to implement the methodology and the results from its application to bus service data from Porto. The data relate to an AFC system integrated with an automatic vehicle location system that records a transaction for each passenger boarding a bus, containing attributes regarding the route, the vehicle, and the travel card used, along with the time and the location where the journey began. Some of these are recorded for the purpose of allowing onboard ticket inspection but additionally enable innovative spatial validation features introduced by the methodology. The results led to the conclusion that the methodology is effective for estimating journey destinations at the disaggregate level and identifies false positives reliably.
  • 23.

    【24hr】Cost Minimization of Charging Stations With Photovoltaics: An Approach With EV Classification

    包量

    机译 光伏充电站成本最小化：EV分类方法
    摘要：This paper proposes a novel electric vehicle (EV) classification scheme for a photovoltaic (PV)-powered EV charging station (CS) that reduces the effect of intermittency of electricity supply and the cost of energy trading of the CS. Since not all EV drivers would like to be environmentally friendly, all vehicles in the CS are divided into three categories: 1) premium; 2) conservative; and 3) green, according to their charging behavior. Premium and conservative EVs are considered interested only in charging their batteries, with noticeably higher rates of charging for premium EVs. Green vehicles are more environmentally friendly and thus assist the CS to reduce its cost of energy trading by allowing the CS to use their batteries as distributed storage. A different charging scheme is proposed for each type of EV, which is adopted by the CS to encourage more EVs to be green. A basic mixed-integer programming (MIP) technique is used to facilitate the proposed classification scheme. It is shown that the uncertainty in PV generation can be effectively compensated, along with minimization of total cost of energy trading to the CS, by consolidating more green EVs. Real solar and pricing data are used for performance analysis of the system. It is demonstrated that the total cost to the CS reduces considerably as the percentage of green vehicles increases and that the contributions of green EVs in winter are greater than those in summer.
  • 24.

    【24hr】Ecological Adaptive Cruise Controller for Plug-In Hybrid Electric Vehicles Using Nonlinear Model Predictive Control

    包量

    机译 基于非线性模型预测控制的插电式混合动力汽车生态自适应巡航控制器
    摘要：Plug-in hybrid electric vehicles (PHEVs) are promising options for future transportation. Having two sources of energy enables them to offer better fuel economy and fewer emissions. Significant research has been done to take advantage of future route information to enhance vehicle performance. In this paper, an ecological adaptive cruise controller (Eco-ACC) is used to improve both fuel economy and safety of the Toyota Prius Plug-in Hybrid. Recently, an emerging trend in the research has been to improve the adaptive cruise controller. However, the majority of research to date has focused on driving safety, and only rare reports in the literature substantiate the applicability of such systems for PHEVs. Here, we demonstrate that using an Eco-ACC system can simultaneously improve total energy costs and vehicle safety. The developed controller is equipped with an onboard sensor that captures upcoming trip data to optimally adjust the speed of PHEVs. The nonlinear model predictive control technique (NMPC) is used to optimally control vehicle speed. To prepare the NMPC controller for real-time applications, a fast and efficient control-oriented model is developed. The authenticity of the model is validated using a high-fidelity Autonomie-based model. To evaluate the designed controller, the global optimum solution for cruise control problem is found using Pontryagin's minimum principle (PMP). To explore the efficacy of the controller, PID and linear MPC controllers are also applied to the same problem. Simulations are conducted for different driving scenarios such as driving over a hill and car following. These simulations demonstrate that NMPC improves the total energy cost up to 19%.
  • 25.

    【24hr】Fast Traffic Sign Recognition via High-Contrast Region Extraction and Extended Sparse Representation

    包量

    机译 通过高对比度区域提取和扩展的稀疏表示实现快速的交通标志识别
    摘要：In this paper, we propose a high-performance traffic sign recognition (TSR) framework to rapidly detect and recognize multiclass traffic signs in high-resolution images. This framework includes three parts: a novel region-of-interest (ROI) extraction method called the (HCRE), the (SFC-tree detector), and a rapid occlusion-robust traffic sign classification method based on the (ESRC). Unlike the color-thresholding or extreme region extraction methods used by previous ROI methods, the ROI extraction method of the HCRE is designed to extract ROI with high local contrast, which can keep a good balance of the detection rate and the extraction rate. The SFC-tree detector can detect a large number of different types of traffic signs in high-resolution images quickly. The traffic sign classification method based on the ESRC is designed to classify traffic signs with partial occlusion. Instead of solving the sparse representation problem using an overcomplete dictionary, the classification method based on the ESRC utilizes a content dictionary and an occlusion dictionary to sparsely represent traffic signs, which can largely reduce the dictionary size in the occlusion-robust dictionaries and achieve high accuracy. The experiments demonstrate the advantage of the proposed approach, and our TSR framework can rapidly detect and recognize multiclass traffic signs with high accuracy.
  • 26.

    【24hr】A Discriminated Release Strategy for Parking Variable Message Sign Display Problem Using Agent-Based Simulation

    包量

    机译 基于Agent的停车可变信息标志显示问题的有区别释放策略
    摘要：With the development and application of intelligent transportation systems (ITS), parking guidance and information system (PGIS) has become a hot topic for research and applications. Parking variable message sign (parking VMS) is the most common form of PGIS currently in use, particularly in providing the space availability information to en-route drivers. The aim of this study is to model drivers' responses to the parking VMSs under various parking information in a dynamical way. To ensure the guiding efficiency and assist drivers to identify parking lots with vacant spaces, the display strategies of parking VMS were studied. A discriminated release strategy with a space occupancy indicator (SOI) was then proposed to determine the display content on the parking VMS, in which an agent-based simulation was introduced to incorporate both parking choice model and traffic assignment algorithm dynamically. Guiding reliability and display strategies were further analyzed to attain a discriminated release strategy with SOI effectively. The results indicate that the guiding reliability was improved by reducing the SOI value of the corresponding parking lot, and the relatively uniform guiding reliabilities of all parking lots were attained by modifying SOI values iteratively. Additionally, the performance by incorporating the waiting time into the parking choice model was investigated and recommended. The discriminated release strategy presented in this study will assist in designing and operating urban PGIS.
  • 27.

    【24hr】Stochastic Delay Analysis for Train Control Services in Next-Generation High-Speed Railway Communications System

    包量

    机译 下一代高速铁路通信系统中列车控制服务的随机时延分析
    摘要：The communication delay of train control services has a great impact on the track utilization and speed profile of high-speed trains. This paper undertakes stochastic delay analysis of train control services over a high-speed railway fading channel using stochastic network calculus. The mobility model of high-speed railway communications system is formulated as a semi-Markov process. Accordingly, the instantaneous data rate of the wireless channel is characterized by a semi-Markov modulated process, which takes into account the channel variations due to both large- and small-scale fading effects. The stochastic service curve of high-speed railway communications system is derived based on the semi-Markov modulated process. Based on the analytical approach of stochastic network calculus, the stochastic upper delay bounds of train control services are derived with both the moment generating function method and the complementary cumulative distribution function method. The analytical results of the two methods are compared and validated by simulation.
  • 28.

    【24hr】From the Editor

    包量

    机译 来自编辑
    • 作者：Ioannou Petros;
    • 刊名：Intelligent Transportation Systems, IEEE Transactions on
    • 2016年第2期
    摘要：
  • 29.

    【24hr】Shared Steering Control Using Safe Envelopes for Obstacle Avoidance and Vehicle Stability

    包量

    机译 使用安全信封的共享转向控制，可避免障碍物和提高车辆稳定性
    摘要：Steer-by-wire technology enables vehicle safety systems to share control with a driver through augmentation of the driver's steering commands. Advances in sensing technologies empower these systems further with real-time information about the surrounding environment. Leveraging these advancements in vehicle actuation and sensing, the authors present a shared control framework for obstacle avoidance and stability control using two safe driving envelopes. One of these envelopes is defined by the vehicle handling limits, whereas the other is defined by spatial limitations imposed by lane boundaries and obstacles. A model predictive control (MPC) scheme determines at each time step if the current driver command allows for a safe vehicle trajectory within these two envelopes, intervening only when such a trajectory does not exist. In this way, the controller shares control with the driver in a minimally invasive manner while avoiding obstacles and preventing loss of control. The optimal control problem underlying the controller is inherently nonconvex but is solved as a set of convex problems allowing for reliable real-time implementation. This approach is validated on an experimental vehicle working with human drivers to negotiate obstacles in a low friction environment.
  • 30.

    【24hr】Randomized Bidirectional B-Spline Parameterization Motion Planning

    包量

    机译 随机双向B样条参数化运动计划
    摘要：This paper presents a motion planner tailored for particular requirements for robotic car navigation. We leverage B-spline curve properties to include vehicle's constraint requirements, thus lowering the search dimensionality. An algorithm, which combines competent exploratory nature of the randomized search methods with vector-valued parameterization steering, is developed here. Vehicle's limitations, along with obstacle's constraints, are satisfied without being hindered by numerical integration and control space discretization of traditional randomized kinodynamic planners. We rely on newly developed theoretical underpinnings to overcome performance issues in rapidly exploring random tree (RRT) solutions. Rigorous simulations and analysis demonstrate that this new approach outperforms recently proposed planners by using an efficient bidirectional RRT-based search, by maintaining continuous state and control spaces, and generating C continuous paths, which are realistic inputs suited for mobile robotic applications and passenger vehicles.
  • 31.

    【24hr】Feature Detection for Vehicle Localization in Urban Environments Using a Multilayer LIDAR

    包量

    机译 使用多层激光雷达的城市环境中车辆定位的特征检测
    摘要：Localization is an important component of autonomous vehicles, as it enables the accomplishment of tasks, such as path planning and navigation. Although vehicle position can be obtained by GNSS devices, they are susceptible to errors and satellite signal unavailability in urban scenarios. Several map-aided localization solution methods have been proposed in the literature, but mostly for indoor environments. Maps used for localization store relevant environmental features that are extracted by a detection method. However, many feature detection methods do not consider the presence of dynamic obstacles or occlusions in the environment, which can impair the localization performance. In order to detect curbs even in occluding scenes, we developed a method based on ring compression analysis and least trimmed squares. For road marking detection, we developed a modified version of the Otsu thresholding method to segment road painting from road surfaces. Finally, the feature detection methods were integrated with a Monte Carlo localization method to estimate the vehicle position. Experimental tests in urban streets have been used to validate the proposed approach with favorable results.
  • 32.

    【24hr】Text Mining the Contributors to Rail Accidents

    包量

    机译 文本挖掘铁路事故的起因
    • 作者：Brown Donald E.;
    • 刊名：Intelligent Transportation Systems, IEEE Transactions on
    • 2016年第2期
    摘要：Rail accidents represent an important safety concern for the transportation industry in many countries. In the 11 years from 2001 to 2012, the U.S. had more than 40 000 rail accidents that cost more than $45 million. While most of the accidents during this period had very little cost, about 5200 had damages in excess of $141 500. To better understand the contributors to these extreme accidents, the Federal Railroad Administration has required the railroads involved in accidents to submit reports that contain both fixed field entries and narratives that describe the characteristics of the accident. While a number of studies have looked at the fixed fields, none have done an extensive analysis of the narratives. This paper describes the use of text mining with a combination of techniques to automatically discover accident characteristics that can inform a better understanding of the contributors to the accidents. The study evaluates the efficacy of text mining of accident narratives by assessing predictive performance for the costs of extreme accidents. The results show that predictive accuracy for accident costs significantly improves through the use of features found by text mining and predictive accuracy further improves through the use of modern ensemble methods. Importantly, this study also shows through case examples how the findings from text mining of the narratives can improve understanding of the contributors to rail accidents in ways not possible through only fixed field analysis of the accident reports.
  • 33.

    【24hr】Multimodal Dynamic Freight Load Balancing

    包量

    机译 多式联运动态货运负载平衡
    摘要：The urban traffic network has temporal and spatial characteristics whose changing conditions have often unpredictable effects on the flow of loads that include passengers and freight. As a result, the current traffic network is unbalanced, leading to high and low peaks of traffic in both time and space. The freight transportation chain can utilize these high and low peaks in the road and rail network in order to utilize more effectively available capacity. The purpose of this paper is to develop a coordinated multimodal dynamic freight load balancing (MDFLB) system to balance freight loads across the rail and road network. The MDFLB system collects and updates information from all the shipping companies and assigns freight loads to the available carriers using an optimization model while taking into account current and predicted dynamical changes in the associated networks. Since the freight loads can change the assumed states of the network, namely, the link travel times, which could then render the solution of the optimization problem no longer optimum, an iterative approach is considered involving online network simulation models. The simulation models are used to test and modify the optimization-based load balancing solution and estimate the new states of the network used by the optimizer. This feedback iterative approach guarantees that the overall cost function is non-increasing and it stops when it converges to a minimum or when a stopping criterion is satisfied depending on the time horizon of interest. A simulation case study that focuses on distribution of freight in an area that includes the two major sea ports in Southern California is used to demonstrate the effectiveness of the proposed coordinated MDFLB.
  • 34.

    【24hr】Travel Time Dynamics for Intelligent Transportation Systems: Theory and Applications

    包量

    机译 智能交通系统的旅行时间动力学：理论与应用
    摘要：This paper demonstrates the limitation of the flow-based travel time functions. This paper presents a density-based travel time function and further develops a fundamental model of travel time dynamics that is built from a given fundamental traffic relationship and vehicle characteristics. The travel time dynamics produce an asymmetric one-sided coupled system of hyperbolic partial differential equations, where the first equation represents the macroscopic traffic dynamics. The existence of the solution for the mathematical model is then presented. The main contribution of this paper is the mathematical development and analysis of the real-time model of travel time. Moreover, this paper also shows various intelligent transportation system applications where travel time is an important factor and where this new model would be extremely useful and important.
  • 35.

    【24hr】Multimodal Impact Analysis of an Airside Catastrophic Event: A Case Study of the Asiana Crash

    包量

    机译 空侧灾难性事件的多峰影响分析：以韩亚空难为例
    摘要：Transportation networks constitute a critical infrastructure enabling the transfers of passengers and goods, with a significant impact on the economy at different scales. Transportation modes, whether air, road, or rail, are intrinsically coupled through passenger transfers and are interdependent. The frequent occurrence of perturbations on one or several modes disrupts passengers' entire journeys, directly and through ripple effects. This paper provides a case report of the Asiana crash in San Francisco International Airport (SFO) on July 6, 2013, and its repercussions on the multimodal transportation network. It studies the resulting propagation of disturbances on the transportation infrastructure in the USA, particularly on the U.S. air transport network and the ground transportation in the Bay Area. The perturbation takes different forms and varies in scale and time frame: cancelations and delays snowball in the airspace, with up to 86% of cancelations in the U.S. due to the SFO crash; highway traffic near the airport is impacted by congestion in previously not congested locations, with low speed and high delays on US 101; and transit passenger demand exhibits unusual traffic peaks in between airports in the Bay Area, with up to 180 passengers more per hour between SFO and Oakland International Airport Bay Area Rapid Transit stations. This paper also investigated the effect of the crash on the social media Twitter. This paper, through a case study, aims at stressing the importance of further data-driven research on interdependent infrastructure networks. The end goal is to form the basis for optimization models behind providing more reliable passenger door-to-door journeys and improved transport network resilience.
  • 36.

    【24hr】Efficient Collective Spatial Keyword Query Processing on Road Networks

    包量

    机译 道路网络上高效的集体空间关键词查询处理
    摘要：The (CSKQ), an important variant of spatial keyword queries, aims to find a set of the objects that collectively cover users' queried keywords, and those objects are close to the query location and have small inter-object distances. Existing works only focus on the CSKQ problem in the Euclidean space, although we observe that, in many real-life applications, the closeness of two spatial objects is measured by their road network distance. Thus, existing methods cannot solve the problem of network-based CSKQ efficiently. In this paper, we study the problem of , where the objects are located on a predefined road network. We first prove that this problem is , and then we propose two algorithms with provable approximation bounds and one algorithm, for supporting CSKQ on road networks efficiently. Extensive experiments using real datasets demonstrate the efficiency and accuracy of our presented algorithms.
  • 37.

    【24hr】A Review of Communication, Driver Characteristics, and Controls Aspects of Cooperative Adaptive Cruise Control (CACC)

    包量

    机译 自适应自适应巡航控制系统（CACC）的通信，驾驶员特性和控制方面的评论
    摘要：Cooperative adaptive cruise control (CACC) systems have the potential to increase traffic throughput by allowing smaller headway between vehicles and moving vehicles safely in a platoon at a harmonized speed. CACC systems have been attracting significant attention from both academia and industry since connectivity between vehicles will become mandatory for new vehicles in the USA in the near future. In this paper, we review three basic and important aspects of CACC systems: communications, driver characteristics, and controls to identify the most challenging issues for their real-world deployment. Different routing protocols that support the data communication requirements between vehicles in the CACC platoon are reviewed. Promising and suitable protocols are identified. Driver characteristics related issues, such as how to keep drivers engaged in driving tasks during CACC operations, are discussed. To achieve mass acceptance, the control design needs to depict real-world traffic variability such as communication effects, driver behavior, and traffic composition. Thus, this paper also discusses the issues that existing CACC control modules face when considering close to ideal driving conditions.
  • 38.

    【24hr】A Deterministic and Stochastic Petri Net Model for Traffic-Responsive Signaling Control in Urban Areas

    包量

    机译 确定性随机Petri网模型用于城市交通响应信号控制
    摘要：The problem of reducing congestion within urban areas by means of a traffic-responsive control strategy is addressed in this paper. The model of an urban traffic network is microscopically represented by means of deterministic and stochastic Petri nets, which allow a compact representation of the dynamic traffic network. To properly model traffic congestion, intersections are divided into crossing sections, and roads have limited capacity. Each intersection includes a multiphase traffic signal, whose sequence of phases is given and represented by a timed Petri net. The control strategy proposed in this paper aims at minimizing queue lengths by optimizing the duration of each signal phase. This is accomplished by heuristically solving a stochastic optimization problem within a receding-horizon scheme, to take into account the actual traffic flow entering the network, thus making the proposed approach traffic-responsive. In this framework, the Petri nets play a key role, as the cost function to be minimized is a function of the marking, and the constraints include the marking state evolution. The proposed strategy is applicable to both undersaturated and oversaturated traffic conditions.
  • 39.

    【24hr】A Hybrid Method for Short-Term Traffic Congestion Forecasting Using Genetic Algorithms and Cross Entropy

    包量

    机译 遗传算法和交叉熵的短期交通拥堵预测混合方法
    摘要：This paper presents a method of optimizing the elements of a hierarchy of fuzzy-rule-based systems (FRBSs). It is a hybridization of a genetic algorithm (GA) and the cross-entropy (CE) method, which is here called GACE. It is used to predict congestion in a 9-km-long stretch of the I5 freeway in California, with time horizons of 5, 15, and 30 min. A comparative study of different levels of hybridization in GACE is made. These range from a pure GA to a pure CE, passing through different weights for each of the combined techniques. The results prove that GACE is more accurate than GA or CE alone for predicting short-term traffic congestion.
  • 40.

    【24hr】Adaptive Sliding-Window Strategy for Vehicle Detection in Highway Environments

    包量

    机译 公路环境下车辆检测的自适应滑窗策略
    摘要：In highway traffic monitoring systems, vehicle detection is one of the most important tasks. To automatically detect vehicles in general CCTV environments, we should effectively handle the problems caused by the following three issues: severe variation in appearance, ambiguities in location, and ambiguities in size. Over the last decade, these issues have been mainly addressed by employing a sliding-window-based image search. Although it is quite effective in many applications, the manual procedure of initializing necessary size models and high computational costs impede the automation of monitoring systems. To remedy these drawbacks, we propose an adaptive sliding-window strategy, where useful size templates are continuously modeled for a given scene, and the detection is performed by adaptively deforming a sliding window based on the obtained templates. This strategy allows us not only to avoid complex user interferences but also to reduce computational costs for vehicle detection. Experiments on real-world highway environments show that the proposed strategy achieved about 23% improved detection accuracy with 43% reduced processing time over the state-of-the-art sliding-window approach without any user assistance.
  • 41.

    【24hr】Microscopic Modeling of a Signalized Traffic Intersection Using Timed Petri Nets

    包量

    机译 定时Petri网的信号交叉口微观建模
    摘要：In this paper, we consider the problem of developing a microscopic model for a signalized traffic intersection using Petri nets (PNs). We propose a two-module timed PN representation, where the first module is to model the traffic intersection and the second module is to model its traffic signal system. We use both deterministic and stochastic transitions in our model, and we describe in detail how they operate by considering both the event and time constraints associated with the physical traffic intersection. We also compare our model with some existing models in literature, and we explicitly state the potential advantages of our model.
  • 42.

    【24hr】Vessel Detection Algorithm Used in a Laser Monitoring System of the Lock Gate Zone

    包量

    机译 闸门区激光监控系统中的船舶检测算法
    摘要：In this paper, we propose a vessel detection algorithm used in an online laser monitoring system in the lock of a hydropower plant. The system has to ensure the strict detection of the position of a vessel in order to prevent the manipulation of pound lock doors while the vessel is in the door zone. This paper describes in detail the monitoring concept, i.e., the detection algorithm implemented in the computer program that performs object detection in the view field of laser scanners. The detection algorithm has been developed in accordance with the modular principle and contains a number of functional partitions based on pattern recognition, i.e., the partition for the recognition of interference, the partition for water surface recognition in the conditions of debris floating on the water surface, the partition for the recognition of interference caused by the overflight of a single bird or a flock of birds, the partition for the recognition of interference caused by meteorological conditions, the partition for the recognition of high waves, and the partition for the recognition and detection of vessels. The main parts of the monitoring system are as follows: infrared laser scanners, controllers, an industrial PC, developed software with the implemented detection algorithm, a database, and a SCADA interface. This monitoring system has a vital role in keeping water transport operations safe and in the preventive maintenance and avoidance of vessel damaging in the area of gates at each end that controls the level of water in the lock chambers. The implementation of the detection algorithm has significantly improved the characteristics of the monitoring system. The system successfully detects all vessels, whereas the number of false detections remains neglectable.
  • 43.

    【24hr】Bayesian Analysis of Behaviors and Interactions for Situation Awareness in Transportation Systems

    包量

    机译 交通运输系统态势感知行为和相互作用的贝叶斯分析
    摘要：In large and crowded transportation sites such as ports, parking lots, or busy streets, the unsafe actions of a moving object (such as a pedestrian, a ship, or a car) may compromise the safety and security of the entire infrastructure. It follows that a full comprehension of the situations taking place in the area could significantly decrease the amount of work performed by human administrators and operators in charge of the zone, reducing also the impact of human errors. The idea behind this paper is to use trajectory data to analyze behaviors (atomic actions without any external influence) and interactions (actions inducted by the presence of another entity) of each target in the scene. Probabilistic techniques applied on a topological map of the scene allow tackling the problem in a robust way, handling the uncertainties arising in such environments. The system is tested in a real maritime scenario, where trajectory data of ships and vessels are used to determine normal and abnormal situations occurring in a canal.
  • 44.

    【24hr】Situation Awareness Framework for Multi-Machine Environments: An Application to Operator Assistive Collision Warning System

    包量

    机译 多机环境的态势感知框架：在操作员辅助碰撞预警系统中的应用
    摘要：Mobile multi-machine environments consist of varying types of objects, either static or dynamic with the state known exactly or with some uncertainty. Sensors observe the environment from different positions and views, such as horizontally from the top of a mobile machine or vertically downward from an external observing machine. In this paper, we propose a simple grid-based framework for representing the information of varying types of objects in a 2-D environment and Bayesian methods for updating this information through observations and prediction models. This information about the current and near-future state of the environment is called situation awareness (SA). SA information can be utilized as the basis of the operator assistance system for enhancing the safety and efficiency of manual and semiautonomous multi-machine work environments. SA information can also be utilized in task planning of autonomous machines, via creating a dynamic costmap for path planning or entropy map for planning the optimal use of sensory systems. This paper aims at real-time mobile multi-machine environments; hence, the SA framework is kept simple for computational feasibility, but is also general enough to be applicable in other environments as well. Discussion on discretization errors and computational complexity are also covered.
  • 45.

    【24hr】Compact Representation of Dynamic Driving Environments for ADAS by Parametric Free Space and Dynamic Object Maps

    包量

    机译 参数自由空间和动态对象图的ADAS动态驾驶环境的紧凑表示
    摘要：We present a novel parametric representation of general dynamic driving environments. It is particularly suitable for near-future Advanced Driver Assistance Systems due to its compactness, inherent consistency between static and dynamic entities, suppression of irrelevant details, as well as its sensor-independent, real-time capable generation. By building upon a common occupancy grid map-based environment representation, cells belonging to dynamic objects are simultaneously extracted, classified, and tracked in an object-based manner via an Interacting-MultipleModel-Unscented-Kalman-Probabilistic-Data-Association (IMM-UK-PDA) filter and cleared from the grid. The remaining static environment grid is subsequently processed by methods from the image analysis domain, followed by an Information Filter-based contour tracking of relevant free space boundaries to create a spatiotemporally smooth compact Parametric Free Space (PFS) map. The PFS map represents the static part of the traffic scene with modest bandwidth requirements. The system runs in real time on an experimental vehicle equipped with an automotive radar and a stereo camera and is evaluated within real traffic environments.
  • 46.

    【24hr】Passenger Compartment Violation Detection in HOV/HOT Lanes

    包量

    机译 HOV / HOT车道中的乘客车厢违规检测
    摘要：Due to the high volume of traffic on modern roadways, transportation agencies have proposed high occupancy vehicle (HOV) and high occupancy tolling (HOT) lanes to promote carpooling. Enforcement of the rules of these lanes is currently performed by roadside enforcement officers using visual observation. Officer-based enforcement is, however, known to be inefficient, costly, potentially dangerous, and ultimately ineffective. Violation rates up to 50%–80% have been reported, whereas manual enforcement rates of less than 10% are typical. Near-infrared (NIR) camera systems have been recently proposed to monitor HOV/HOT lanes and enforce the regulations. These camera systems bring an opportunity to automatically determine vehicle occupancy from captured HOV/HOT NIR images. Due to their ability to see through windshields of vehicles, these cameras also enable enforcement of other passenger compartment violations such as seatbelt violation and driver cell phone usage, in addition to determining vehicle occupancy. In this paper, we propose computer vision methods for detecting vehicle occupancy, seatbelt violation, and driver cell phone usage from NIR images captured from HOV/HOT lanes. Our methods consist of two stages. First, we localize the vehicle's front windshield and side window from captured HOV/HOT images using the deformable part model (DPM). Next, we define a region of interest in the localized images for each violation type and perform image classification using one of the local aggregation-based image features, i.e., bag-of-visual-words (BOW), vector of locally aggregated descriptors (VLAD), and Fisher vectors (FV), and compare their performances for each case. We also compare the performance of DPM-based detection with the image classification methods for vehicle occupancy and seatbelt violation detection. A data set over 4000 images including front/side view vehicle images with seatbelt and cell phone violations was collect- d on a public roadway and is used to perform the experiments.
  • 47.

    【24hr】Energy-Efficient Communication-Based Train Control Systems With Packet Delay and Loss

    包量

    机译 具有数据包延迟和丢失的基于节能通信的列车控制系统
    摘要：Designing a train control system over wireless train-wayside communications is a challenging task due to the packet delay and loss caused by unreliable wireless communications. In this paper, we study the performance optimization issues in communication-based train control (CBTC) systems with both packet delay and loss introduced by random transmission errors and frequent handoffs in train-wayside communications. A networked control system (NCS) model is formulated for multitrain CBTC systems with packet delay and loss. Then, we propose a novel train control scheme to enhance the quality of service (QoS) of CBTC systems. In the proposed scheme, medium-access control layer retry limit adaption is used to minimize the energy consumption, and guidance trajectory update is used to mitigate the trip time tracking errors. Extensive simulation results show that the QoS of CBTC systems can be substantially improved in the proposed scheme. The energy consumption and trip time error can be reduced in both static and time-varying wireless environments.
  • 48.

    【24hr】Optimal Operation Point Detection Based on Force Transmitting Behavior for Wheel Slip Prevention of Electric Vehicles

    包量

    机译 基于力传递行为的电动汽车防侧滑最佳操作点检测
    摘要：The optimal wheel slip prevention control of ground vehicles aims at maintaining the operation point around the optimal one to achieve the maximum adhesion utilization, which contributes not only to ensure the adhesion stability but also to obtain the optimal traction performance, particularly being useful for the low grip conditions. However, the uncertainty of tire–road contacts brings great challenges for the optimal operation point determination. This paper proposes a novel methodology for the online search of the optimal operation point under uncertain low grip conditions. First, the force transmitting behavior is analyzed in the stable adhesion state and the unstable slipping state. Then, a determination law to identify the optimal operation point via investigating the adhesion force is proposed, which functions during the transient process from the stable region to the unstable region under the action of an increasing drive force. The adhesion force is estimated using the wheel rotational speed and the wheel drive torque. Both the simulation and experimental results verify the effectiveness of the proposed methodology.
  • 49.

    【24hr】Model-Based Diagnosis of Multi-Track Level Crossing Plants

    包量

    机译 多轨平交道口的基于模型的诊断
    摘要：As is witnessed by railway statistics, level crossing (LC) safety has always been one of the major concerns for railway stakeholders. LC safety is an issue at the crossroads between technical aspects, operational procedures, and human factors, making the search for effective solutions a challenging task. This paper deals with technical aspects related to LC safety. In particular, we carry out an analysis pertaining to the diagnosability of two main failure classes that can affect the protection system at automatic LCs. In this paper, a labeled Petri net behavioral model depicting the global system function, including both the normal operation and the faulty behavior, is first established. Petri net has been used as the modeling formalism mainly for its mathematical foundations and expressiveness capabilities. Using such a mathematical notation is highly recommended to deal with dependability issues in safety-critical systems, particularly in railways. Based on the established model, different model-based approaches for the diagnosis of discrete event systems (DESs) will be brought into play to investigate the diagnosability of two considered failure classes, whereas the obtained results will be compared. In particular, a technique that we have established, which is based on on-the-fly and incremental analysis of the model state space, shows interesting efficiency, making it possible to tackle the combinatorial explosion problem, which arises particularly when considering multi-track LCs. The originality of this technique w.r.t. existing DES model-based diagnosis approaches is that, in general, a partial building/investigation of the state space suffices to decide diagnosability and build an online diagnoser. Findings pertaining to LC safety are drawn based on a thorough discussion of the obtained results. In particular, we show how the diagnosability analysis outputs can be taken into account in the global LC risk assessment process.
  • 50.

    【24hr】Distributed Fault-Tolerant Control of Virtually and Physically Interconnected Systems With Application to High-Speed Trains Under Traction/Braking Failures

    包量

    机译 虚拟和物理互连系统的分布式容错控制，在牵引/制动故障下应用于高速列车
    摘要：This paper investigates the tracking control problem of dynamic systems consisting of physically connected subsystems with virtual connections through local communication, where unknown unidentical nonlinearities, time-varying yet undetectable actuation faults, and varying actuation authorities are involved. The local communication nature and the physical uncertain interactions among the subsystems, together with the unpredictable actuation failures and control authority variation, make the underlying problem nontrivial, calling for a control solution that is not only decentralized (distributed) but also adaptive and fault tolerant. In this paper, with the aid of the concepts of generalized parameter estimation error and virtual regrouping, a distributed and fault-tolerant control design approach is presented by using local (neighboring) information exchange only. This method is applied to develop tracking and braking control schemes for high-speed trains subject to traction and braking failures. The proposed distributed control is capable of simultaneously coping with the physical interactions among the subsystems, compensating the uncertain control gains, and accommodating the undetectable actuation faults, as authenticated and verified by theoretical analysis and numerical simulations.
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