Dynamic optimal route search algorithm for car navigation systems with preferences by dynamic programming

Optimal route search to the destination is one of the most important functions of car navigation devices. The development of road traffic infrastructure has made it possible to receive real‐time information of the traffic situation. Route search algorithms for car navigation devices make use of this information to avoid the traffic congestions. Such algorithms should find the new optimal route efficiently when the traffic situation changes. Usually, the minimum traveling time or distance is considered to define the optimal route. However, the minimum traveling time or distance is not always what the user is looking for. The user may prefer to travel on a certain route even at the cost of traveling time or distance. Car navigation devices should consider such preferences when finding the optimal route. In this paper, we propose a dynamic programming algorithm to find the optimal route considering that it should deal with the changes of the traffic situation and multiple criteria. The proposed method uses the information from the previous computation to find the new optimal route considering user preferences when the traveling time of the road section changes. The proposed method was applied to a real road network to find the optimal route. Results show that the proposed method can find the user‐preferred optimal route. Simulation results also show better calculation time of the proposed method compared to the Dijkstra algorithm. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

An application of Q‐value‐based dynamic programming with Boltzmann distribution to real‐world road networks

In order to alleviate traffic congestion and improve the efficiency of traffic systems from a global perspective, a dynamic traffic management model is proposed in this paper. The proposed model is applied to the large‐scale microscopic simulator SOUND/4U based on the real‐world road network of Kurosaki, Kitakyushu, Japan. All the vehicles in the simulator follow the direction from the route guidance of the dynamic traffic management model, in which the extended Q‐value‐based dynamic Programming with Boltzmann distribution (QDP‐BD) and the time‐varying traffic information are used to generate the routes from the origins to the destinations. The simulation results show that the proposed QDP‐BD can reduce traffic congestion and improve the efficiency of the whole traffic system effectively compared with the greedy method in the real‐world road network. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Fast computation of Q‐value‐based dynamic programming on road networks

One of the essential components of vehicle navigation systems is route planning. The single shortest path problem and multiple shortest path problem have been widely studied for route planning. This paper introduces a Q‐value‐based dynamic programming using the division concept for solving both single and multiple shortest path problems on road networks. The proposed algorithm divides the whole network into different divisions, and the updating of Q values in each division is one stage for searching the optimal routes on road networks. The proposed algorithm can greatly save the computational time without any preprocessing on the road networks. The proposed algorithm is also systematically studied in various sizes of road networks. The simulation results show the efficiency and effectiveness of the proposed algorithm on large‐scale road networks. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

MBFP generalized association rule mining and classification in traffic volume prediction

Genetic network programming (GNP)‐based time‐related association rules mining method provides a useful mean to investigate future traffic volume of road networks and hence helps us to develop traffic navigation system. Further improvements have been proposed in this paper about the time‐related association rule mining using generalized GNP with multibranches and full‐paths (MBFP) algorithm. For fully utilizing the potential ability of GNP structure, the mechanism of generalized GNP with MBFP is studied. The aim of this algorithm is to better handle association rule extraction from the databases with high efficiency in a variety of time‐related applications, especially in the traffic volume prediction problems. The generalized algorithm which can find the important time‐related association rules is described, and experimental results are presented considering a traffic prediction problem. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

电子地图匹配算法在GPS和DR组合车载导航系统中的作用

在许多车载导航系统中,用GPS和DR组合导航的方法来给车辆定位,然而由于不知道GPS的噪声,估计的位置会有不期望的误差.为了解决这个问题,电子地图匹配的方法被介绍.它使用电子地图来修正定位误差.文章介绍了用电子地图来修正GPS和DR组合导航系统的定位误差.     

Mobile navigation services with augmented reality

In this study, we combine augmented reality (AR) with the technique of assisted global positioning system to construct a guiding system of AR and design the guiding graphs metaphorically, so that the system interface operation is used more intuitively. We further investigate the availability of the system, and present an empirical study to statistically show that the guiding system of AR significantly outperforms that of plane map in terms of the finishing time of mission and correctness. Finally, according to the results of questionnaire of the system availability, we induct six essential factors influencing the guiding system availability of AR, namely guiding service usability factor, user esthetics of design factor, guiding service technique factor, guiding service creativity factor, guiding service entertainment factor, and guiding service practicality factor. The results of the study could be extended to other related studies. In terms of task completion time and accuracy rate, AR navigation is obviously better than the two plane map navigation modes. The users can find the direction of the destination within 7 s on average, and the accuracy rate is as high as 97.73%. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Information dissemination in self-organizing intervehicle networks

Intervehicle communication (IVC) is an emerging topic in research and application that is getting increasing attention from all major car manufacturers. In this paper, a novel method for scalable information dissemination in highly mobile ad hoc networks is proposed: segment-oriented data abstraction and dissemination (SODAD). With SODAD, information can be distributed in an information range multiple orders of magnitude larger than the transmission range of the air interface, even if only 1%-3% of all vehicles are equipped with an IVC system, e.g., during market introduction. By restricting the method to the dissemination of map/position-based data, scalability is achieved. In the second half of this paper, an example application for the SODAD method is presented: a self-organizing traffic-information system (SOTIS). In SOTIS, a car is equipped with a satellite navigation receiver, an IVC system, and a digital map. Each individual vehicle collects traffic information for its local area. Using the digital map, the traffic information is analyzed based on road segments. By distributing the information in the ad hoc intervehicle network using the SODAD method, a decentralized traffic information system is created. The performance of the proposed methods is evaluated using network simulation with vehicular mobility models. Simulation results for typical scenarios are presented. Furthermore, a prototype implementation based on commercially available standard hardware demonstrates the feasibility of the proposed approach.     

夜间天津城市道路交会区户外LED显示屏照明现状调研及分析

随着城市建设的不断发展,户外LED显示屏作为广告新载体越来越多的得到运用。这种新型的广告载体,在夜间对城市道路交会区交通极易产生干扰。本文以天津市区为例,针对道路交会区这一特殊的空间,对夜间户外LED屏的现状进行实地调研,以期对户外LED显示屏的现状有一个初步的了解,对今后在城市道路交会区如何更科学合理地使用这种广告载体,减少其对交通干扰提供一定的参考依据。     

降雨天气下停车视距模型与安全限速分析

降雨导致交通事故频发.分析了降雨对能见度、道路摩擦系数等产生的影响,比较AASHTO,NCHRP停车视距模型,通过停车视距模型得到了不同水膜厚度,不同能见度下的安全限速值.在降雨天气下,对易发生交通事故的路段提出了可变限速控制,采用逐级限速的标准,使汽车从高速区即将驶入异常事故多发路段时之前可以有充分的时间和距离来降低车速,用来提高汽车在雨天行驶的安全性,可以有效避免交通事故的再次发生,提高高速公路对异常情况的应变能力.     

Model-Based Probabilistic Collision Detection in Autonomous Driving

The safety of the planned paths of autonomous cars with respect to the movement of other traffic participants is considered. Therefore, the stochastic occupancy of the road by other vehicles is predicted. The prediction considers uncertainties originating from the measurements and the possible behaviors of other traffic participants. In addition, the interaction of traffic participants, as well as the limitation of driving maneuvers due to the road geometry, is considered. The result of the presented approach is the probability of a crash for a specific trajectory of the autonomous car. The presented approach is efficient as most of the intensive computations are performed offline, which results in a lean online algorithm for real-time application.      

Spatial-temporal traffic data analysis based on global data management using MAS

The spatial-temporal traffic data analysis based on global data management is a newly developed and crucial approach to help traffic managers having the global view of urban traffic status in the level of road network, which is very clearly useful in traffic control and route guidance. The multiagent systems are used in traffic data management with full consideration of the characteristics of traffic data and the cooperation and workflow among them. In software implementation of data management, the agent-based common object request broker architecture is adopted taking the distributed urban traffic data in the large area under network environments into account. Based on the global traffic data, the approach of visualized spatial-temporal analysis is then induced. The similarity of traffic data is analyzed first for each link and its profile is achieved to undertake the primary processing of urban traffic data. Furthermore, analysis results are shown on the basis of the geographic information systems for transportation. The two types of visualization, pseudocolor and contour maps, are adopted in the demonstration to display the traffic status graphically and its changing frames. Among the applications in some big cities in China, the case of urban traffic analysis for Beijing is studied to demonstrate the implementation of the approach.     

Analysis of energy consumption of elevator group supervisory control system based on genetic network programming

Elevator Group Supervisory Control System (EGSCS) is a traffic system, which provides the transportation services for passengers in modern buildings. As the elevator systems include uncertainty due to the future arrival of the passengers, it difficult to model, analyze, and optimize the elevator group supervisory control system. Recently, artificial intelligence technology has been used in such complex systems. Genetic Network Programming(GNP), a graph‐based evolutionary method extended from genetic algorithm and genetic programming, has been already applied to EGSCS. On the other hand, since energy consumption is becoming one of the greatest challenges in the society, it should be taken as one of the criteria of the elevator operations. The elevators with maximum energy efficiency are therefore required. In this paper, the GNP is used to solve EGSCS with energy consumption (EC). Moreover, the idle car assignment has been embedded in the proposed method. Finally, the simulations show that some factors should be introduced into GNP in order to deal with the higher EC in the light traffic of the elevator systems. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

基于汽车OBD车联网的设计与实现

汽车 OBD车联网的设计与实现,对人们的出行和道路交通安全都具有重要的意义。针对 OBD模式的车联网设计和实现形式进行研究,以OBD诊断端口提供的车体CAN总线信息为车联网的信息来源,主要着重于车与人之间的信息互联。从 OBD车联网硬件电路设计与实现和 OBD车联网软件设计与实现两个方面入手,将整个系统集成并进行系统功能测试。经过 OBD车联网离线测试和在线测试的实验结果表明,该系统具有精度高、性能稳定等特性,能快速高效的将当前车的信息通过 OBD诊断端口反馈给用户,实现人与车的信息互联。     

Flywheel size design considerations and experimental verification using a 50‐kW system for voltage sag compensator with flywheel induction motor

Flywheel energy storage systems can be used as an uninterrupted power supply system because they are environmentally friendly and have high durability. The use of a simple voltage sag compensator with a low‐speed heavy flywheel and a low‐cost squirrel‐cage induction motor/generator is proposed. First, the ability of the proposed system to maintain the load voltage at 100% when the grid is experiencing voltage sag is validated experimentally. Next, design guidelines for the flywheel stored energy are discussed. Experimental verification of a 50‐kW‐class system is carried out, and the results show good agreement with the developed design guidelines. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(1): 36–44, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21252     

基于边缘卷积的交通锥筒点云数据分割方法

本研究以用于构建临时道路中的交通锥筒为研究目标,以多线激光雷达采集的临时道路三维点云数据为输入,提出一种基于图理论的图神经网络模型,该模型可实现点云数据分割,并提升模型对无序性点云数据学习效果。以无人驾驶方程式赛车为实验平台,针对交通锥筒进行网络训练与测试,实验结果表明,图神经网络模型对交通锥筒的分割准确率达到88.6%,比PointNet模型提升了约10%,此外,该模型在稀疏雷达点云数据下还具有一定泛化能力,有较好的适用性。     

Automated highway systems

Currently, intelligent transportation systems are being developed and implemented in various forms. Advanced traffic management systems (ATMS), automatic traveler information systems (ATIS) and driver support systems are all a reality today. However, many challenges remain on the road to realizing a fully automated highway system (AHS). The complexity of developing large distributed systems such as AHS has raised warning flags in the computer science community. Unexpected complex interactions between the software and hardware can induce errors that can be fatal. The authors argue that these issues should provide a cautionary note to practicing engineers before deploying a fully automated highway system     

Parametric macromodeling for S‐parameter data based on internal nonexpansivity

We propose a novel parametric macromodeling method for systems described by scattering parameters, which depend on multiple design variables such as geometrical layout or substrate features. The new concept of internal nonexpansivity for bounded real systems is introduced. It is used in combination with suitable interpolation schemes to interpolate a set of state‐space matrices, and hence poles and residues indirectly, to build accurate parametric macromodels. Stability and passivity are guaranteed by construction over the design space of interest. Pertinent numerical examples validate the proposed parametric macromodeling method. Copyright © 2012 John Wiley & Sons, Ltd.     

基于第三代移动通信技术的动态车载导航系统的设计

提出了一种包含实时路况信息采集功能的车载导航系统的设计方案;给出了这种车载导航系统的工作流程图;讨论了第三代移动通信技术在车载导航系统的交通信息采集与传输上的应用。     

动态能源与地理信息融合的光储充电站电动汽车充电路径引导

电动汽车(EV)的出行、充电行为在对交通系统运行规律造成影响的同时,也使得能源网络负荷的时空分布发生改变。为此,考虑光储充一体化系统的特点,结合大规模EV、区域路网、配电网以及光储充电站的动态信息,构建了精细化的车-站-路-网动态融合模型;在此基础上,分别从用户、交通路网、电网3个角度构建包含行程时间、交通拥堵情况、电网稳定性的多目标优化函数。针对当前模型的高复杂度,运用分层规划和双向搜索思路对LPA*路径规划算法进行改进,从而实现动态环境下的充电路径引导。以某市一区域路网为例进行仿真,结果表明：与现有的策略相比,所提充电路径引导策略能很好地解决因EV充电带来的局部道路拥挤、区域光储能源消纳不均衡等问题。