信号交叉口改进延误模型及实测分析

【目的】为了给国内城市信号交叉口规划设计和服务评价提供科学依据,研究城市交叉口延误模型。【方法】对比Australian延误模型和Canadian延误模型,提出改进的延误模型,再采用牌照法,对饱和度接近1的道路交通延误进行实测,并把实测结果与3个模型进行对比。【结果】改进的延误模型在饱和度较低和较高的情况下,与Australian延误模型和Canadian模型的模拟数据很接近;在饱和度接近1时,改进的延误模型与实测结果能较好吻合;改进模型与Brilon和Wu的马尔科夫链方法比较,形式简单,计算简便,可操作性好。【结论】改进的模型适合用于平面混合低速的城市交叉口道路延误分析。     

基于遗传算法的交叉口信号优化控制模型

本文结合题设,根据交叉口延误的随机特征,建立了交叉口延误的概率模型。给出了通用性算式,使用遗传算法等方法对该非线性模型进行了求解,得到了秒级精度的最优解。并对该模型做了深入分析,实现了相应的仿真计算。进一步对计算结果进行了比较,初步得出该交叉口信号控制模型有较强的鲁棒性。     

基于最大互信息系数的高饱和度交叉口延误模型修正

提出了一种基于最大互信息系数的高饱和度交叉口延误修正模型。使用无人机调查HCM延误模型中所有变量的实测数据,运用rjava调用MIC算法编码对HCM模型中的变量及组合进行最大互信息相关度分析,通过统计软件R对交通流量、通行能力、绿信比等与延误值进行互信息相关度比对检验,选取非线性关系对现有模型进行重新修正,根据赤池信息准则筛选出最佳解释数据、包含最少自由参数的备选项作为优化模型。最后以修正模型计算高(过)饱和度交叉口案例的延误值,与原HCM2010模型和交通仿真模拟值进行结果比对,得出本文提出的新模型具有更高的精确度。     

基于等效流率的两相位信号交叉口车均延误模型

为了进一步完善交叉口车均延误计算理论,从微观交通流角度出发,利用等效交通流方法,研究城市两相位信号控制交叉口车均延误改进模型。通过分析两相位信号控制交叉口延误产生过程,分析了额外延误的产生机理,建立了等效流率模型。在充分考虑额外延误影响的条件下,对Webster车均延误模型进行改进,并结合江都市两相位信号交叉口实际案例,对比分析并计算出改进前后Webster延误模型在两相位信号交叉口的车均延误。研究结果表明:改进后的模型在两相位交叉口车均延误计算中精度更高。     

不良天气下城市道路平面信号控制交叉口延误分析?

立足于乌鲁木齐市中心城区平面信号控制交叉口,以乌鲁木齐市西虹西路与南昌南路交叉口为例,通过调查不同天气下交叉口的交通流特性,研究正常与不良天气下信控交叉口机动车的延误,并采用点样本实测法和HCM法分析计算不同天气下该交叉口不同车道的延误值。在此基础上提出该交叉口综合治理措施。研究结果表明,与正常天气相比,不良天气下交叉口机动车延误增加20%以上,且两种计算方法得出的交叉口延误值基本接近,为乌鲁木齐市在交通规划和设计中提供参考依据。     

钩形弯交叉口信号协同控制优化方法研究

针对车辆在钩形弯交叉口与相邻常规交叉口间的整体运行特性，建立了各条车道的车辆平均延误计算模型。以各交叉口的周期时长和相位绿灯时间为约束，钩形弯交叉口与相邻常规交叉口间的车辆平均延误最小为目标，建立了信号协同配时方案。以位于苏州市高新区内有轨电车沿线的两个相邻交叉口为例，采用实际数据验证所建立的方法，并设置钩形弯渠化方案。将设置的钩形弯交叉口与其相邻常规交叉口的信号协同作为改进方法，在VISSIM软件中对比分析改进方案与现状方案的车辆延误指标。实验结果表明，钩形弯交叉口与相邻常规交叉口的信号协同优化方法可有效提高交叉口的通行能力，尤其是干道直行机动车的通行能力，可降低车辆的平均延误。     

拓宽交叉口平均延误计算方法研究

文中详细分析了拓宽路口的车辆驶出率,应用路口拓宽条件下车辆累计到达—离开图给出了拓宽交叉口的均匀延误计算公式,对传统的溢流延误模型进行了修正,进而提出了拓宽交叉口平均延误的计算模型。     

城市道路信控交叉口车辆延误分析与治理对策

文章以合肥市三孝口信控交叉口为例,分析了城市道路信控交叉口车辆的运行过程和确定延误方法,分别采用韦伯斯特模型法和点样本实测法对其进行延误计算和比较,结果表明两者接近。最后评估了三孝口信号交叉口的服务水平,并提出综合治理对策,为城市交通规划、交通管理和区域交通控制提供参考依据。     

基于交叉口处机动车交通行为概率的延误模型

通过分析信号控制交叉口处机动车的交通行为,利用交叉口的信号周期、有效绿灯时间,求得各种交通行为的概率和平均延误时间,提出一种基于分析各种交通行为概率的交通延误的模型。以石家庄市中山东路与建设南大街交叉口为例,采用Beckham模型对其进行交通流延误的计算。经过对结果的对比,误差为2%,在规定的误差范围内,说明基于分析交通行为概率的延误模型可以为计算交叉口处车辆的平均延误提供一种估计方法,并且求得的平均延误也可以作为评价交叉口服务水平的指标之一。     

单进口放行方式下交叉口行人嵌套相位设计

依据单进口放行方式下的信号相位设计原理,考虑到行人与不同相位机动车之间的冲突,利用行人二次过街方案设置原理,提出了单进口放行方式下交叉口行人嵌套相位设计方案;并给出了该方案下行人过街延误计算模型。运用VISSIM仿真软件对南宁市快环路下某信号交叉路口进行模拟分析。结果表明:该方案可行有效,实施行人二次过街嵌套相位方案后,交叉口机动车平均延误降低了22.1%,该相位下行人延误减少了50.7%。进一步,当行人流量不大于1 000 per/h时,行人延误计算模型接近仿真值。     

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.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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     

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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