城市快速路车辆换道影响仿真分析及策略研究

城市快速路作为城市主干交通网具有重要作用,车辆换道是影响城市快速路交通运行状态的主要因素。基于北京市东南五环实地交通调查数据,构建并标定了城市快速路车辆换道仿真模型,通过Vissim仿真比较自由换道和强制换道的影响,研究交通需求、交通组成、分离比例、换道次数与城市快速路交通流特性的关系,分析交通需求和换道次数的共同作用。结果表明,平峰时疏解交通需求,高峰时优化横向分布。通过远端分流,控制大中型货车驶入并设置慢车道,诱导车辆提前或延后驶出相邻匝道,倡导提前换道处罚强行换道等措施,改善城市快速路换道路段的交通运行状况。     

城市快速路交织区运行风险预测模型

为了探究城市快速路交织区交通特点,提出交织区运行风险预测分析方法.首先基于城市快速路交织区断面线圈数据及自然驾驶试验数据,分析城市快速路交织区运行特点,结果表明交织区车辆变道行为导致其运行风险增大;然后基于VISSIM仿真试验方法,分析交织区运行风险影响因素,建立运行风险预测模型,同时采用K均值聚类分析法提出风险分级标准;最后采用无人机采集的交通流数据进行运行风险预测模型误差分析.研究成果可为城市快速路的设计管理提供工具和参考.     

基于自然驾驶数据的高速公路出口区换道风险模型

依托上海自然驾驶实验数据,提取高速公路出口区的交通流特性数据和驾驶行为样本.以单向四车道高速公路出口为例,考虑不同道路交通环境和出匝换道路径因素,基于比例优势模型构建高速公路出口区换道风险模型.在该模型基础上生成换道风险图谱,解析高速公路出口区换道风险分布特征,为车流控制管理提供理论决策支持.     

基于自然驾驶数据的高速公路出口换道决策模型

为研究高速公路出口换道行为特性,分析驾驶员换道决策机理,依托上海自然驾驶实验所采集的驾驶行为样本和车辆运行参数,采用Google Earth标定行驶路径及高速公路出口范围以筛选出口样本,并根据车道偏移参数和方向盘转角识别换道行为;以单向4车道高速公路为例,综合考虑行驶路径信息和交通流环境,基于随机效用理论,采用Binary Logit(BL)模型拟合构建换道决策模型,得到车道效用函数;基于效用函数作出高速公路出口范围内在自由流、稳定流和拥挤流水平下的分车道效用分布图,并进行同质性和异质性分析.结果表明,换道决策模型准确率达到86.21%,各变量影响均可得到合理解释;根据效用分析,出匝车辆的换道行为是出匝意愿与通行环境改善需求两方面平衡的结果,兼有强制性换道与自由性换道的行为特性,且随着交通流状态由自由流过渡到拥挤流,后者影响逐渐增强,表现为上游向左换道行为趋于活跃、下游向右换道位置接近出口.     

基于驾驶模拟实验的快速路交织区运行风险评价

对快速路交织区运行风险进行有效评价可为交通组织优化设计与交通管控的实施提供依据.基于8自由度驾驶模拟仿真平台,建立16个场景模拟不同交织区长度、不同交通流密度、不同行驶路径的城市快速路交织区运行状况;基于20名驾驶员的实验数据,分析车辆运行状态特性,并提出快速路交织区运行风险评价指标;进一步分析运行风险评价指标与场景变...     

基于双车驾驶模拟的城市快速路驾驶人换道交互行为特征

为研究换道情境下换道车辆与目标车道后方车辆驾驶人间的交互行为,设计了城市快速路换道场景,搭建出双车驾驶模拟实验平台,招募40名驾驶人,开展了8种换道场景下的双车实验并进行驾驶风格问卷调查.基于换道阶段实验数据,分析对比了单、双车实验中两车驾驶人的交互行为特征和差异.利用多元Logistic回归模型,分析不同因素对换道交互决策的影响.结果表明：单、双车实验中,换道车辆和目标车道后方车辆的行为特征具有明显差异,从而验证了开展双车实验的必要性;不同的道路限速、换道方向、驾驶风格等因素下,两车驾驶人关键行为变量呈现差异性;道路限速、车辆初始速度、两车纵向位置差、横/纵速度差、纵向速度乘积等均对两车换道交互决策产生显著影响.     

下游交叉口设置对快速路出口通行能力的影响

为缓解下游交叉口设置造成快速路出口不畅、特别是下游交叉口进口排队车辆易上溢堵塞快速路出口问题,在考虑快速路辅路流量基础上,利用间隙接受理论,建立快速路出口通行能力计算模型;通过分析辅路流量、信号周期、绿信比、交叉口进口道通行能力及进口道排队车辆传播速度5个参数,提出快速路下游交叉口进口道排队长度模型;通过分析不同变量对交叉口进口车辆排队长度的影响,提出快速路出口与下游交叉口的优化设计方案。结果表明：随着辅路流量增加,快速路出口通行能力呈缓慢下降趋势;随着交叉口辅路方向绿信比增加,排队长度快速变短;出口与下游交叉口可采用外侧式匝道设计,优化辅路进口方向绿信比,可有效避免快速路出口堵塞。     

基于时依等比例风险回归模型的换道时长影响因素

研究了基于时依等比例风险回归模型的换道时长（LCD）影响因素。利用开源HighD数据集,提取了560条完整的换道（LC）轨迹,对整体换道时长分布进行了非参数估计;引入时依等比例风险回归模型,对当前车辆换道时长的影响因素进行分析。结果表明：大部分驾驶员在3~8 s内完成换道行为;共有6个变量显著影响换道时长,其中最为关键的为当前车辆自身车速,同时当前车道的前车与目标车道的后车对换道时长的影响也非常显著。     

基于轨迹数据的高速公路养护维修作业区车辆换道特性研究

为了确保高速公路养护维修作业区人车安全、科学制定交通组织和管控措施,基于无人机航拍行车风险区域内高质量交通流视频,提取车辆运行轨迹数据以研究车辆换道特性.为克服将开启转向灯作为车辆换道起始点的不合理之处,提出根据车辆运行轨迹线与车道线之间的几何关系确定车辆换道起始点、结束点的方法;提出利用行车风险区各车道换道频数、频率热力图描述换道起始点空间分布的方法;建立二次回归模型,刻画分车道的车辆换道长度与换道起始点的关系.研究结果表明:封闭车道上的车辆需要全部换道,可通行车道上部分车辆也存在换道行为,且距封闭车道越近受影响越大,车辆换道率越高;各车道车辆换道行为存在横向延迟扩散现象,距离封闭车道越远的可通行车道上车辆换道频率高的区域出现越晚;随着换道起始点越来越靠近工作区,行车风险区域内车辆换道长度呈下降趋势,并且距封闭车道越远的可通行车道上车辆换道长度下降越明显.     

基于分层logit模型的车辆换道行为研究

研究分析复杂交通场景中车辆换道行为,揭示车辆运行特性及其规律。基于效用理论方法,以实现驾驶行为决策效用最大化为目标,建立车辆换道分层Logit模型。系统分析影响车辆行为变化的因素,建立各层次参数变量相关模型。仿真分析表明:较一般的车辆行为模型,车辆换道分层Logit模型更能准确地描述实际交通场景中车辆换道的行为决策过程,有效提高车辆运行效率。研究结果为智能车路协同与交互行为、车辆可变限速技术、自适应巡航控制技术等提供理论依据和技术支撑。     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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     

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