基于元胞自动机的多车道机非混合道路交通流

车辆的行驶受到本车道以及邻近车道前后邻近车辆的影响,在城市交通中机非混合对车辆行走的影响尤为复杂。通过研究路段上机非混合通行交通流的本质特性,综合考虑非机动车对机动车换道规则及加减速规则的"摩擦"和"阻滞"干扰影响,建立描述路段混合通行道路交通流的元胞自动机(CA)模型,从不同的机非混合比例下道路交通流的流量、速度变化情况,流量与车辆到达率关系,交通流相位相变等方面仿真模拟混合交通流的机非干扰机理。     

40Gb/s,100Gb/s以太网IEEE P802.3ba标准研究

介绍了下一代以太网标准IEEE P802.3ba的研究进展、IEEE P802.3ba任务组关于速率的选择与应用目标的确定、协议结构和物理媒质相关特性.重点阐述其物理层的分层模型和工作原理,详细分析了协议的弹性和扩展性设计,并对标准的规模商用前景作了介绍.     

基于车道映射矩阵的多车道车辆计数系统

针对城市交通路口的多车道车辆数量统计问题,提出基于车道映射矩阵的车道划分方案。根据车道映射矩阵分布情况判断车道中心线位置,利用相邻车道中心线间的距离对车道进行划分,与车辆计数算法结合,实现多车道车辆计数系统。该方案能够减少环境因素对车道划分的影响,在白天与夜晚情况下均取得较好效果。实验结果表明,该方案准确率为93.6%,能够适应复杂道路,多车道实时车辆计数系统准确率能够达到91%以上,在保证系统实时性的基础上,提供了较高的系统准确性和鲁棒性。     

多车道交通流非线性优化控制模型及遗传算法

多车道高速公路交通流的递阶控制结构分为协调控制层、路段控制层和车辆控制层,文中提出了路段控制层的优化控制模型。该模型以路段上交通流量与平均速度最大化为控制目标,以该路段上车辆在各车道的分配比例为决策变量。决策变量的个数比传统线性模型大为减少。为避免一般优化算法可能得到局部最优解的缺点,采用遗传算法求解所提出的非线性规划模型。仿真算例验证了模型及求解算法的有效性。     

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.     

基于缩放延迟微分方程的交通流仿真

研究基于缩放延迟微分系统的的多车道交通流量数值仿真。为了模拟多车道宏观动态变化的道路交通流量问题,采用了微分动力学系统的原理,建立了基于缩放延迟微分方程的道路交通流量模型,并给出了模型的数值求解算法。给出不同密度下多车道车辆仿真结果,讨论了缩放延迟模型权重参数和缩放因子对系统稳定点的影响;将缩放延迟模型与常延时模型的数值结果进行了对比。仿真结果表明,当车流密度处于高密度时,缩放延迟模型能更好模拟交通流量的实际变化情况,对多车道交通流量的真实模拟具有更好的参考价值。