“一路一线直行式”公交模式下公交车行驶诱导和调度集成方法

为了充分发挥"一路一线直行式"公交模式的优越性,在车站与路口协同设计与控制的基础上,在交叉口信号配时的约束下,提出一种公交车行车速度优化和诱导、公交车调度的集成方法.该方法根据公交线路各个站点之间的距离、公交车辆的平均行驶速度、各个站点的平均上下客时间,优化公交车辆的行驶速度和发车时间.通过该方法可确保公交车到达有站点的信号交叉口时,利用红灯等候时间上下客;到达无站点信号交叉口时,无需停车,顺利通行,从而避免信号交叉口信号控制对公交车辆通行造成的负面影响,减少公交车在信号交叉口的停车次数和延误.基于概率论分析了该方法的效益,并通过实例说明该方法的可行性.     

基于强化学习算法的公交信号优先策略

综合分析了影响城市公共交通系统运行的多种因素,提出了一种新型的基于强化学习算法的城市公交信号优先控制策略.该策略利用强化学习算法的试错-改进机制,根据不同交通环境下信号控制策略实施后反馈的结果,迭代优化路口的公交信号优先控制策略,从而使其具备了自学习的能力.基于Paramics的仿真实验表明,该算法能够在保障路口正常交通秩序的同时,显著提高公交车运行效率.     

基于公交优先的多路口车速引导控制方法

对于复杂的交通流,传统公交信号优先有可能会破坏干线协调控制效果,为此,提出公交优先可变车速引导和多交叉口信号配时优化的集成方案. 以背景公交线路需求的历史数据为前提,通过定时检测公交车流状况,优化公共周期、绿信比和相位差,实时调整多路口交通信号配时,以此改善公交车的通行效率. 同时,以福州市金山大道三个交叉口为例,进行Vissim仿真模拟验证,仿真结果表明： 所提方法可有效提升多交叉口公交车流的通行效益,减少公交车辆的延误,最大化减少停车次数.     

基于公交分担率的城市客运交通枢纽选址优化

在用户均衡理论的基础上,首先研究超级网络条件下公交车与小汽车交通流量的相互影响,并以公交分担率最大为目标,建立在不同的枢纽选址方案下城市交通网络中公交车流量和小汽车流量分配最优化模型.进而,以公交车与小汽车的出行成本、枢纽建设的土地成本之和作为总成本,以总成本最小为优化目标,建立城市交通枢纽选址优化的双层规划模型.最后,运用案例验证模型,并提出枢纽选址优化的相关建议.     

公交专用道选址与公交优先控制组合优化模型

针对信控网络下的公交专用道选址问题,从宏观网络优化角度提出公交专用道选址和公交信号优先控制的组合优化模型.上层模型是以最小化路网用户总出行时间(包括小汽车用户和公交车用户)为目标的公交专用道网络布局、交叉口车道功能分配和被动公交优先控制策略组合设计决策;下层模型是在信控网络下以最小广义出行成本为目标的小汽车和公交车客流分配模型.提出了基于连续权重平均法的遗传算法求解该模型,并通过算例验证了该模型的有效性与实用性.算例结果表明:相比单一公交专用道选址方案,公交专用道布设方案和公交信号优先控制方案同步优化设计能够更大程度地发挥公交优先效益,对路网通行效率的改善效果更优.     

快速公交车辆发车间隔与信号优先协调研究

研究快速公交车辆发车间隔与路口信号优先的协调优化问题. 针对快速公交全线路口信号选用定周期的优先感应控制方案,提出协调优化问题的衡量指标. 选用遗传算法提出发车间隔与信号控制参数综合优化的求解算法. 以北京的BRT1线为例,应用VISSIM仿真软件与VC++程序进行了算法实现. 实例结果表明:在不同的车速、发车间隔、信号控制方案的组合下,经过优化可以有效提高车辆的速度和准点率,实现真正意义上的公交优先.     

假设速度服从截断正态分布的公交车队密度离散模型

基于实地收集数据,针对我国大城市主道路上公交车流量普遍较大的情况,考虑公交车有别于小汽车的特有的运行特性,引入公交车停站平均延误参数,利用截断正态分布建立了相邻交叉口有停靠站的公交车队密度离散模型,分析了上游交叉口的排队公交车辆在绿灯放行后往下游道路行驶过程中的离散特性,利用分段函数方式构造了公交车队在时空坐标上的交通流密度分布函数.针对相邻交叉口有一个停靠站的信号协调控制实例,提出了在某一时刻公交车队头部驶过和尾部未驶过下游断面的车辆数计算公式,推导了上下游交叉口断面处的流量分布模式,结合实测数据分析验证了该模型的有效性.     

关联信号交叉口排队长度计算模型

以相邻信号交叉口的最大排队长度为研究对象,分析了路段长度、相位差、绿信比等时空参数对路口最大排队长度的影响机理.基于交通波理论建立了最大排队长度计算模型,通过微观交通仿真实验对模型进行了验证,并提出了相邻信号交叉口时空协调指数的概念及其计算方法,分析了时空协调指数对相邻信号交叉口最大排队长度的影响规律.研究表明,该模型能定量计算相邻信号交叉口不同时空参数下的最大排队长度值,对相邻信号交叉口的时空协调设计具有指导意义.     

基于深度学习的交通路口自动识别

基于车辆轨迹数据提取道路信息已经成为数字地图更新的一种有效而廉价的方法，引起了广泛的研究。交通路口是道路信息的重要组成，如何快速而准确提取交通路口具有一定的挑战。深度学习的快速发展为解决这一问题提供了一种新的思路。本文针对轨迹数据在交通路口的分布特性，首先提出一种基于LSTM深度学习的转弯轨迹模式自动提取方法，通过统计航向变化规律对路口转弯轨迹进行建模分类，然后采用LSTM深度模型学习轨迹时间序列，从而实现转弯轨迹模式的自动识别，训练好的模型可以对新的未知轨迹数据实现自动快速地提取转弯轨迹。其次，针对因路口转弯点的稀疏性而影响准确定位路口中心这一难点，本文提出一种联合补偿点计算和转弯轨迹航向变化幅度的方法选取路口候选点，然后通过聚类路口候选点识别道路交叉口。为验证和评估该方法的有效性，采用福州市鼓楼区出租车实际轨迹数据进行测试。结果表明，该方法道路交叉口识别准确率达到96.7%，为电子地图实时更新及无人驾驶自动导航应用等提供关键技术支持，同时我们开放该方法源代码和实验数据，以便于其他研究者开展相关研究。     

绿波协调下公交车辆在交叉口的延误影响分析

道路交通绿波协调以及拥堵协调等控制策略提升了车流运行效率和通行能力,一定程度上缓解了路网交通压力,但面向绿波协调的交叉口信号控制尚未考虑对公交车辆运行的影响。现对绿波协调控制下交通流运行特性进行分析,利用交通流运动学理论确定公交车交叉口延误的影响变量,建立定量化模型进而得到交叉口公交车延误因子。选取示范路线青岛西海岸经济新区长江路干线交叉口,采用组合优化方法对延误因子模型进行验证,得出交叉口信号绿信比、公交运行速度对公交车延误的影响。结果表明,增加绿信比、适当提高公交车速可有效提升交叉口整体通行效率,减少公交车在交叉口的延误。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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