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To study the dynamics of mixed traffic flow consisting of motorized and non-motorized vehicles, a car-following model based on the principle of collision free and cautious driving is proposed. Lateral friction and overlapping driving are introduced to describe the interactions between motorized vehicles and non-motorized vehicles. By numerical simulations, the flux-density relation, thetemporal-spatial dynamics, and the velocity evolution are investigated in detail. The results indicate non-motorized vehicles have a significant impact on the motorized vehicle flow and cause the maximum flux to decline by about 13%. Non-motorized vehicles can decrease the motorized vehicle velocity and cause velocity oscillation when the motorized vehicle density is low. Moreover,non-motorized vehicles show a significant damping effect on the oscillating velocity when the density is medium and high, and such an effect weakens as motorized vehicle density increases. The results also stress the necessity for separating motorized vehicles from non-motorized vehicles. 相似文献
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采用熔融法制备了Tb3+掺杂的Bi2O3-B2O3系统玻璃,使用激发、发射及拉曼光谱分析了光学碱度与玻璃结构及发光性能的关系,同时绘制了Tb3+、Bi3+和Bi2+的能级图。研究结果表明:Tb3+掺杂的Bi2O3-B2O3玻璃由[BO3]、[BiO3]、[BO4]及[BiO6]共同组成,且随着光学碱度由0.63增加到0.93,玻璃的结构逐渐疏松。高的光学碱度使部分Bi3+变为Bi2+,发出571 nm(2P3/2(2)→2P1/2)的光,Bi3+→Tb3+的能量降低。在光学碱度及Tb3+、Bi3+和Bi2+离子的共同作用下,随着光学碱度的提高,玻璃的发光颜色由黄绿色变为白色。 相似文献