共查询到20条相似文献，搜索用时 15 毫秒
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The conventional car-following theory is based on the assumption that vehicles will travel along the center line of lanes.
However, according to the field survey data, in complex traffic conditions, a lateral separation between the leader and the
follower frequently occurs. Accordingly, by taking lateral separation into account, we redefined the equation of time-to-collision
(TTC) using visual angle information. Based on the stimulus-response framework, TTC was introduced into the basic General
Motors (GM) model as a stimulus, and a non-lane-based car-following model of steady-state traffic flow was developed. The
property of flow-density relationship was further investigated after integrating the proposed car-following model with different
parameters. The results imply that the property of steady-state traffic flow and the capacity of each lane are highly relevant
to the microscopic staggered car-following behavior, and the proposed model significantly enhances the practicality of the
human driving behavior model. 相似文献
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For automated vehicles,comfortable driving will improve passengers’ satisfaction.Reducing fuel consumption brings economic profits for car owners,decreases the impact on the environment and increases energy sustainability.In addition to comfort and fuel-economy,automated vehicles also have the basic requirements of safety and car-following.For this purpose,an adaptive cruise control (ACC) algorithm with multi-objectives is proposed based on a model predictive control (MPC) framework.In the proposed ACC algorithm,safety is guaranteed by constraining the inter-distance within a safe range; the requirements of comfort and car-following are considered to be the performance criteria and some optimal reference trajectories are introduced to increase fuel-economy.The performances of the proposed ACC algorithm are simulated and analyzed in five representative traffic scenarios and multiple experiments.The results show that not only are safety and car-following objectives satisfied,but also driving comfort and fuel-economy are improved significantly. 相似文献
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基于应急疏散交通特征的车辆跟驰模型 总被引：1，自引：0，他引：1
提出了一个应急交通疏散车辆跟驰模型（EECM）,模型首次在车辆最小安全间距的动力学推导过程中纳入驾驶员心理行为影响因素,使得跟驰过程更客观地反映在紧急疏散状态下的交通流和疏散驾驶行为特性．通过文献研究分析传统跟驰理论与应急交通疏散跟驰特性的区别,并进一步进行驾驶员问卷调查对应急交通疏散条件下的驾驶心理行为特性进行统计分析,提炼出驾驶员行为差异分布系数和经验判断系数2个参数,并将其纳入车辆安全间距的动力学推导过程,建立了基于驾驶行为特性和最小安全间距的应急交通疏散车辆跟驰模型,应用GPS技术对北京东三环劲松路段高峰小时交通流跟驰数据,对EECM进行了比较验证,结论有力地支持了EECM模型及问卷量化分析的合理性． 相似文献
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应用基于时域有限差分法(FDTD)的XFDTD仿真工具分析研究2.4/5.2/5.7GHz穿戴式躯域传感器网络(W-BSN)的体表路径损耗和时延特性.仿真环境为置于自由空间中的简化三维人体模型.分析结果表明,当工作频率较高时,路径损耗相对较小;当发送点和接收点都置于主躯干时,路径损耗与最小等效体表距离遵循对数拟合模型,并且2.4,5.2,5.7GHz下的衰减指数分别为4.7,4.1和4.0.另一方面,各接收点的首径延迟约小于2ns,而最大时延扩展为10ns.为避免多径延迟引起的码间干扰,建议W-BSN的传输速率应小于108符号/s. 相似文献
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将“时滞”引入了“人-环境-人”传染病模型的反应扩散系统．并对该系统进行了分析．将其行波解的讨论转化为对二阶常微分系统的上、下解的讨论．通过上、下解方法证明了具有时滞项的传染病模型的行波解的存在性，发现行波解的波速范围随时滞的增大而扩大． 相似文献
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多数经济时间序列存在惯性或迟缓性，通过对这种惯性的分析可以研究时间序列的内在规律并预测经济的发展。本文用BOX—Jenkins模型和指数平滑法对四川省人均GDP时间序列进行建模和短期预测分析，结果显示，四川省提出的“十一五”经济增长目标是可以实现的，但应防止新一轮经济增长周期带来的经济增长速度减慢， 相似文献
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针对发车间隔这一公交车辆调度中需要考虑的关键因素,提出了一种优化线路发车间隔的双层规划模型.该模型从公交公司和乘客两者利益出发,上层模型以最小化公交系统中因发车频率设置而产生的时间和经济总成本为目标;下层模型是公交客流分配模型,用来描述发车间隔优化后的客流分配情况.设计了一种混合遗传算法,即模拟退火遗传算法,来求解模型.最后,以常州市某几条线路为例,利用公交数据对模型和算法进行了检测.结果表明：所提出的线路发车间隔优化模型体现了公交供需关系是合理的,而且求解算法是有效的. 相似文献
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通过修正ＣＰＮ模型,提出了一种多变量模糊模型,并基于该模型推导出相应的模糊多步预测控制算法．修正模型采取竞争输出方式,具有局部表示特性．在线学习,只需调整少量参数,所以学习速率快,可在线自组织建模．基于修正模型推导出的控制算法,简单,具有在线自适应性,适于解决多变量时滞问题．将此控制算法用于造纸过程,仿真结果证明了其良好的控制效果． 相似文献
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对于网络时滞小于一个采样周期的网络控制系统,建立了系统的离散化模型,并在此基础上研究了基于观测嚣的故障检测问题．把不确定时滞对残差系统产生的影响描述为未知输入,将残差产生器设计归结为后置滤波器和观测器增益矩阵的求解,给出了网络控制系统巩故障检测的矩阵Ricatti方程方法,进一步通过算例进行MATLAB仿真研究,验证提出算法的有效性． 相似文献
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经过线性化处理的TCP/AQM拥塞控制模型是一个输入带有时滞的源端链路端组合系统。首先修改了带有延迟的网络拥塞控制模型;计算其平衡状态并进行线性化,采用积分变换算法进行延迟变换为无时滞的线性模型,并建立相应的状态空间模型。在模型矩阵参数抖动但有界限的条件下,应用变结构控制算法设计控制器,基于李雅普诺夫稳定性理论和线性矩阵不等式方法给出了该控制器控制的系统可到达和渐进稳定的可行条件,同时根据该条件设计网络链路端主动队列管理算法。最后,仿真结果表明了该算法的有效性。 相似文献
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张晞 《广东技术师范学院学报》1998,(4)
本文提出采用主延时段和微调延时段串联的程序结构来实现较长时间软件延时的算法,并提出了在存在外部中断或计数中断而又必须采取软件延时的情况下,采用多个微调延时程序相串联来补偿外中断的影响,提高延时精度的措施。并以MCS－51系列单片机为例给出了具体程序,本文的软件延时方案和提高延时精度的措施应用于多种装置的软件延时程序中,明显提高了延时精度和程序调试效率,运行情况良好。 相似文献
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针对一种新型混联式汽车电泳涂装输送机构控制方法存在收敛时间较长问题,提出一种有限时间收敛滑模控制方法。首先采用解析法对机构进行运动学分析,并基于拉格朗日法建立输送机构动力学模型;提出一种快速终端滑模有限时间收敛控制方法,实现新型混联式输送机构控制的有限时间收敛;然后设计有限时间滑模观测器,实时观测被控对象模型中的不确定参数以及外部随机干扰并加以前馈补偿,以进一步提高系统鲁棒性,同时解决快速终端滑模控制存在的抖振问题;最后运用Lyapunov稳定性理论证明该控制方法的稳定性,利用MATLAB对控制方法进行仿真,并将其应用于新型混联式输送机构样机进行实验,结果表明该控制器具有跟踪误差小、稳态精度高、响应速度快、鲁棒性好的特点。 相似文献
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This paper focuses mainly on the stability analysis of two-lane traffic flow with lateral friction, which may be caused by irregular driving behavior or poorly visible road markings, and also attempts to reveal the formation mechanism of traffic jams. Firstly, a two-lane optimal velocity (OV) model without control signals is proposed and its stability condition is obtained from the viewpoint of control theory. Then delayed-feedback control signals composed of distance headway information from both lanes are added to each vehicle and a vehicular control system is designed to suppress the traffic jams. Lane change behaviors are also incorporated into the two-lane OV model and the corresponding information about distance headway and feedback signals is revised. Finally, the results of numerical experiments are shown to verify that when the stability condition is not met, the position disturbances and resulting lane change behaviors do indeed deteriorate traffic performance and cause serious traffic jams. However, once the proper delayed-feedback control signals are implemented, the traffic jams can be suppressed efficiently. 相似文献
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A modified 3D finite element (3D-FE) model is developed under the FE software environment of LS-DYNA based on characteristics of stagger spinning process and actual production conditions. Several important characteristics of the model are proposed, including full model, hexahedral element, speed boundary mode, full simulation, double-precision mode, and no-interference. Modeling procedures and key technologies are compared and summarized: speed mode is superior to displacement mode in simulation accuracy and stability; time truncation is an undesirable option for analysis of the distribution trend of time-history parameters to guarantee that the data has reached the stable state; double-precision mode is more suitable for stagger spinning simulation, as truncation error has obvious effects on the accuracy of results; interference phenomenon can lead to obvious oscillation and mutation simulation results and influence the reliability of simulation significantly. Then, based on the modified model, some improvements of current reported results of roller intervals have been made, which lead to higher accuracy and reliability in the simulation. 相似文献
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张宁 《福建工程学院学报》2017,(4):367-370
提出将一种进化的神经网络模型——极限学习机应用于短期电力负荷时间序列预测中,该方法具有模型参数设置少、训练速度快和良好的泛化能力等明显优点。通过实例分析表明该模型的预测精度要优于BP神经网络模型,同时也验证了该模型应用于短期负荷预测的有效性和可行性。 相似文献
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The Car-following models is a kind of microscopic simulation model for vehicular traffic, which describe the one-by-one following
behaviors of vehicles in the same traffic lane. As a common traffic phenomenon, following behavior is of great importance
in the micro-study of intelligent traffic control. Compared with other traffic-flow models, car-following model embodies the
human factors and reflects the real traffic situation in a better way. This paper gives a systematic review of the development
and actuality of car-following models by introducing and analyzing in detail the advantages and disadvantages of GHR model,
OV model, CA model and fuzzy-logic model. In addition, local stability and asymptotic stability of car-following models are
discussed in this paper. 相似文献