????????????г??????????о?

车载导航系统（IVNS）能提供实时有效交通信息辅助驾驶人选择最佳路径.为了探讨IVNS的市场渗透率对路网运行效益（交通效益和环境效益两方面）的影响，本文运用宏观动态交通网络模型METANET建立仿真平台，用反馈式动态交通分配模型描述IVNS路径诱导下驾驶人的行为，以总排队时间和总耗费时间作为交通效益评价指标，用反映速度—加速度关系的机动车排放和燃油消耗关系模型——VT-Micro 模型计算机动车排放量和燃油消耗量，并用货币价值量化排放减少带来的直接经济效益(包括大气污染治理费用和燃油消耗节省).对一个算例路网进行仿真，仿真结果表明：IVNS能够有效均衡路网交通，改善路网交通拥挤，尽管使NOx排放增加，却降低了HC、CO排放，减少了燃油消耗，带来了巨大的经济效益.综合考虑IVNS市场渗透率的交通效益和环境效益，建议可将市场渗透率控制在0.2~0.3左右.研究旨在为相关部门设计评价IVNS，优化路网运行效益提供辅助决策依据.

Simulation on Route Guidance Benefit of In-Vehicle Navigation System

In-vehicle navigation system(IVNS) usually provides real-time traffic information to assist drivers to choose optimal routes.To explore the route guidance effect of IVNS’s market penetration rate to freeway networks,including traffic benefit and environment benefit,this paper uses macroscopic dynamic traffic network model to develop a simulation platform.It uses dynamic traffic assignment model to describe route guidance mechanism of the IVNS and adopts total waiting time and total time spend as traffic benefit indicator.The VT-Micro model is used to measure vehicle emissions and fuel consumption.Moreover,the study calculates the direct economic benefits in terms of air pollutant treatment cost saving and fuel consumption.Taking a network with two origins and two destinations as an example,the simulation shows that the IVNS can effectively equilibrium freeway network’s demand,improve freeway network efficiency,reduce mobile source emissions and create huge economic benefits.Market penetration rate is recommended to value from 0.2 to 0.3 in view of traffic benefits and environment benefits.This simulation system is effective for designing and evaluating the IVNS.It also provides the basis for decision-making and references for relevant departments to improve the operational efficiency of traffic networks.