基于马尔可夫链的驾驶人视觉转移特征

为了不割裂视觉转移过程的连续性,运用动态聚类方法,对驾驶人注视点的视野平面解析坐标进行聚类,实现驾驶人注视区域划分。在考虑驾驶人注视行为在时间轴上关联性的基础上,分析驾驶人注视行为在各注视区域间转移模式的齐次性,运用马尔可夫链理论,探讨各注视区域间视觉转移概率的求解方法,并对5名不同驾驶经验驾驶人的眼动数据进行统计,求得其一步转移概率矩阵和平稳分布,分析驾驶人视觉转移特征。分析结果表明：驾驶人对任一注视目标都需要多次重复注视才能获取足够的信息,且注视点主要集中在前方车道远处、前方车道近处、右侧车道和左侧车道4个区域。     

草原公路平曲线交通标志设置类型对驾驶人视觉特性的影响

典型草原公路线形以长直线接大半径平曲线为主,平曲线段交通标志设置类型多样。为了对比分析平曲线段交通标志设置类型对驾驶人视觉特性的影响,选取14名驾驶人开展典型草原公路实驾试验,同步采集驾驶人在无标志及设置线形诱导标、线形诱导标+减速丘、示警桩等交通标志平曲线段的眼动数据,对比分析交通标志设置类型对驾驶人注视强度、视点转移特性的影响。数据结果表明：驾驶人在设置线形诱导标及线形诱导标+减速带的曲线段注视时长较短、注视频率较低,注视强度较小,注视转移分布范围较广且较均匀。在设置示警桩的曲线段,驾驶人的注视时长与注视频率则均较大,使其注视强度显著增加,驾驶人在不同区域之间转移的概率较大。在无标志平曲线段,驾驶人的注视点范围较窄,但因无交通标志的引导与警示,驾驶人注视强度大于设置线形诱导标段。     

驾驶人注视点分布对预瞄时间求解精度的影响分析

预瞄是驾驶人模型中的重要环节,预瞄时间的准确性决定了驾驶人模型乃至整个模型的稳定性与精确性.为探究驾驶人注视点分布集中程度对预瞄时间求解精确度的影响.利用眼动仪采集驾驶人眼动数据,对驾驶人眼动数据进行处理得到注视点.利用注视点百分比表征驾驶人注视点分布集中程度,利用预瞄时间置信区间长度表征预瞄时间准确度.探究不同路段上的驾驶人注视点集中程度与预瞄时间求解精度之间的关系.研究表明：不同路段上,当注视矩阵中的元素大于一定值时,预瞄时间的置信区间长度在一定范围之内波动,同时在行驶过程中,驾驶人注视点集中程度越高,注视区域越固定,预瞄时间的求解精度越高.     

基于雾天高速车路协同模拟驾驶的驾驶人视觉信息加工模式

为探讨雾天高速公路车路协同系统信息介入对驾驶人视觉信息加工模式的影响,首先,依托驾驶模拟平台设计了车路协同环境下的雾天高速公路驾驶模拟实验,获取驾驶人的视觉行为参数;其次,将前方道路定义为关键兴趣区域,分别提取驾驶人在全局水平及兴趣区域的注视、扫视等显性视觉特性指标,并分析其分布规律;最后,采用因子分析方法获取信息提取...     

高速公路和隧道交通标志位置有效性的眼动研究

交通标志是交通安全的重要保障,其位置的不同对驾驶员有效获取标志信息具有重要影响。为研究交通标志位置的有效性,选取驾驶员视角的高速公路和隧道交通标志图片制作模拟场景开展眼动实验;将场景中交通标志的区域划为兴趣区域;采集了30个被试的首个注视点的注视顺序、首次进入时间、首个注视点的注视时间、总的注视时间等指标数据;运用SPSS 24.0统计软件和假设检验方法分析实验采集的眼动数据。结果表明:在高速公路场景中交通标志显著有效位置为(3)(右上)和(6)(右中),在隧道内场景中交通标志显著有效位置为(6)(右中)和(4)(左中)。实验结果可以为高速公路、隧道等路段交通标志位置的设置提供一定的科学参考。     

车道变换与直行时的驾驶人注视转移特性

针对驾驶人在车道变换与直行过程中的视觉转移问题,利用眼动仪获取了20名驾驶人在真实道路驾驶过程中的注视行为数据。将注视范围划分为7个区域,分别统计了驾驶人在7个区域内的注视概率,以及在7个区域之间的转移概率。研究结果表明:无论是车道变换还是直行,驾驶人对当前车道和目标车道的注视概率始终是最高的,最大概率值为70.2%;车道变换过程中驾驶人对相应方向的后视镜注视概率较高,且向左、向右变换车道时的注视转移特性总体上呈现一定的对称性;车道变换过程中驾驶人的注视转移区域主要集中于原始车道、目标车道和相应方向的后视镜之间;直行时驾驶人主要在当前车道、相邻车道与前方远处之间进行注视转移。研究为自动识别驾驶人的换道意图提供了有益的参考。     

山区高速公路门架式标志牌视认特性研究

为了研究山区高速公路不同路基形式下门架式标志牌处的驾驶人眼动特征,通过多条高速公路的实车试验,利用Smart Eyepro5.7眼动仪采集和记录驾驶人的眼动参数和注视行为。通过对行车录像的逐帧分解,得到了路堤和路堑的段数,并分别筛选出路堤和路堑的门架式标志牌路段数。采用视野平面法划分驾驶人行车视域,分别统计路堤、路堑和门架式标志牌各视域的注视分布情况;并对应驾驶人的眼动数据进行视觉适宜性和敏感性分析。结果表明:位于不同路基形式上,门架式标志对驾驶人眼动特征的影响具有显著性差异。在路堤段的视觉适宜性要高于路堑段,而路堑段的视觉敏感性要高于路堤段;路堤和路堑的右侧近处是驾驶人视觉较为敏感的区域;路堑段右侧近处的信息量较大,而路堤段右侧远处的信息量较大;道路前方是最敏感区域,信息量也最大。门架式标志牌是驾驶人的视觉适宜和敏感目标,驾驶人视点明显抬高,前方上侧是敏感区域。在同等条件下,门架式标志牌宜设置在路堑段。     

位置设置对煤矿安全标志显著性影响的眼动分析

为探讨位置设置对煤矿安全标志显著性的影响,运用文献综述法,结合人类工效学,确定煤矿安全标志可能设置的6个位置。选取主井驱动机房、井下皮带运输巷道、轨道运输巷道和辅助运输巷道4个煤矿生产作业场景图作为视觉刺激材料,借助Tobii眼动仪记录了30名被试者识别6个位置的安全标志时的注视点个数、首次进入时间、首个注视点的注视时间和注视点总持续时间等实验数据。结合Tobii的可视化分析和统计学方法分析,将注视点持续时间作为被试者评价煤矿安全标志显著性的定量指标。结果表明:煤矿安全标志被设置在右侧或右上侧位置时,可视化分析的热点图中红色区域较大也较集中,且兴趣区坐落的注视点个数较多和持续时间较长,则这2个位置能更好的增强安全标志显著性。企业可通过规范煤矿安全标志位置设置来增强其显著性,实现煤矿安全标志的有效应用。     

基于驾驶人视认特性的城市道路指路标志设置

为了提高城市道路指路标志设置的有效性和科学性,根据驾驶人视认特性的实验数据研究其设置方法.利用眼动仪和GPS采集了不同光照条件下驾驶人视认指路标志的特性数据,建立了基于驾驶人视认特性的指路标志设置参数计算模型,并将计算的设置参数与规范值进行了比较.研究发现,驾驶人对指路标志的注视时间随速度和路名数目的增加而增大,且非专业驾驶人的注视时间大于专业驾驶人,顺光条件下的注视时间小于夜间.驾驶人对指路标志的视认距离随速度的增加而减小,顺光条件下的视认距离大于夜间.分别满足专业和非专业驾驶人视认要求的主要设置参数存在显著差异,部分规范值不能满足非专业驾驶人对指路标志准确视认的要求.     

考虑驾驶人视觉搜索能力的雨天公路限速设计

为解决雨天行车时，由于车速过高导致驾驶人无法准确识别公路路侧信息的问题，本研究首先基于注意分配理论选取车速、驾驶人视野图片清晰度、视线角度和注视分布比例作为雨天行车驾驶人的注意分配指标，结合Fisher判别理论建立雨天视觉搜索能力量化模型。其次利用UC-win/Road模拟驾驶软件搭建试验平台，以降雨强度和车速作为影响因素，研究二者协同作用下的驾驶人注意分配指标的变化规律，构建降雨强度-车速与视觉搜索能力的关系模型，并提出降雨强度与限速的匹配方案。结果表明，车速和降雨强度的增加都会导致驾驶人难以观察道路远方的交通信息，驾驶人为降低行车风险，会改变视觉搜索策略，转而增加对道路前方的关注程度，进而降低了对观测目标的视觉搜索效率。因此，当车速和降雨强度匹配不当时，驾驶人需要花费更多努力将注意转移至观测目标所在的兴趣区域，导致无法及时发现路侧交通信息。此外，视觉量化模型的整体判别准确率为85.94%，可以较好地评价雨天环境下驾驶人视觉搜索能力。最后分别对传统基于停车视距的限速方案和基于驾驶人视觉搜索能力的限速方案进行了对比，结果表明基于停车视距的限速模型计算的限速值较高。为避免由于车速过高导致...     

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