Vehicular network technology is frequently used to provide several services and applications for drivers on road networks. The proposed applications in the environment of road networks are classified into three main categories based on their functions: safety, traffic efficiency, and entertainment. The traffic efficiency services are designed to enhance the moving fluency and smoothness of traveling vehicles over the road network. The grid layout architecture of the downtown areas provides several routes toward any targeted destination. Moreover, since several conflicted traffic flows compete at the road intersections, many vehicles have to stop and wait for safe situations to pass the road intersection without coming into conflict with other vehicles. The traffic efficiency applications in this scenario are designed to select the most efficient path for vehicles traveling toward their targeted destination/destinations. Moreover, other applications aimed to decrease the queuing delay time for vehicles at road intersections. In this article, we review several recently proposed mechanisms that worked to enhance the fluency of traffic over downtown road networks and point to the expected future trends in this field.

中文翻译：

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市区道路交通效率应用

车载网络技术经常用于为道路网络上的驾驶员提供多种服务和应用。道路网络环境中的拟议应用根据其功能分为三个主要类别：安全性、交通效率和娱乐性。交通效率服务旨在提高行驶车辆在路网上行驶的流畅性和顺畅性。市区的网格布局架构提供了通往任何目标目的地的多条路线。此外，由于多个冲突的交通流在道路交叉口竞争，许多车辆不得不停下来等待安全的情况通过道路交叉口而不会与其他车辆发生冲突。此场景中的交通效率应用程序旨在为车辆前往其目标目的地选择最有效的路径。此外，其他应用旨在减少车辆在道路交叉口的排队延迟时间。在本文中，我们回顾了最近提出的几种机制，这些机制旨在提高市中心道路网络的交通流畅性，并指出该领域的预期未来趋势。