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1.
基于驾驶员动态视觉理论,利用3D-MAX和UC-win/Road模拟了道路视错觉控速标线,采用SMI2.1眼镜式眼动仪检测并记录了25名被测试者的眼动数据,分析了标线关键参数对驾驶员瞳孔面积变化率指标和运行速度的影响,并建立趋势面模型进行定量分析。通过敏感性分析,得到标线三个关键参数对瞳孔面积变化率的影响程度。结果表明:标线的横向宽度、角度、间距对行车速度降低有显著影响,颜色和线宽对其影响不显著。随着标线的横向宽度增大和间距变小,驾驶人产生车道变窄和车速增加的错觉越加明显,瞳孔面积变化增大。当视错觉控速标线角度为30°~45°时,瞳孔面积变化率较小;当视错觉控速标线的角度为135°~150°时,驾驶员的瞳孔面积变化率增大,在150°时最明显,角度为135°时次之。三个关键参数对瞳孔面积变化率的影响排序为角度间距横向宽度。  相似文献   

2.
基于驾驶员动态视觉理论,利用3D-MAX和UC-win/Road模拟了道路视错觉控速标线,采用SMI2.1眼镜式眼动仪检测并记录了25名被测试者的眼动数据,分析了标线关键参数对驾驶员瞳孔面积变化率指标和运行速度的影响,并建立趋势面模型进行定量分析。通过敏感性分析,得到标线三个关键参数对瞳孔面积变化率的影响程度。结果表明:标线的横向宽度、角度、间距对行车速度降低有显著影响,颜色和线宽对其影响不显著。随着标线的横向宽度增大和间距变小,驾驶人产生车道变窄和车速增加的错觉越加明显,瞳孔面积变化增大。当视错觉控速标线角度为30°~45°时,瞳孔面积变化率较小;当视错觉控速标线的角度为135°~150°时,驾驶员的瞳孔面积变化率增大,在150°时最明显,角度为135°时次之。三个关键参数对瞳孔面积变化率的影响排序为角度间距横向宽度。  相似文献   

3.
公路视错觉减速标线参数优化   总被引:1,自引:0,他引:1  
为提高道路危险路段运营安全水平,促使驾驶人主动降低车辆运行速度至安全范围,对比并优化了减速标线的形式及设计参数。依据人在动态环境下视错觉减速标线作用机理,对鱼刺形视错觉减速标线各设计参数进行分析和初选,并提出变间距减速标线相隔距离的计算方法。将不同设计参数进行组合,依据正交试验方案,利用仿真试验平台和实际道路试验,对比各种形式标线的实际减速效果。研究表明:不同设计参数的鱼刺形减速标线,其实际减速效果有很大差异,合理的参数设计方能产生良好的减速效果;与等间距标线相比,变间距减速标线的减速效果更优。  相似文献   

4.
杨波  邓华 《科学技术与工程》2020,20(35):14694-14700
为了研究公路主动发光的荧光标线视认性,利用UC-win /Road 软件对公路荧光标线进行仿真模拟,采集了20名驾驶员的眼动数据,定量分析了不同标线宽度和布设方式下,荧光标线视认性对驾驶员注视点占比和瞳孔面积变化率影响的规律。最后,通过室外实车实验的方式对仿真结果进行验证。结果表明:直线路段标线宽度为100%的方案是最佳方案,当辉度值为3坎德拉每平方米(cd/m2)时,为最经济方案;曲线路段标线施划在车道边缘线外侧且间距为9m效果最佳。  相似文献   

5.
根据驾驶员视认过程确定视错觉减速标线有效性的影响因素,建立基于ANP-SPA理论的视错觉减速标线有效性综合评价模型.选取平原区高速公路大桥为研究路段,鱼刺形减速标线为评价对象,构建驾驶模拟实验场景,邀请60名被试进行实验,采集车速、察觉距离、心理感知等数据.计算结果表明,鱼刺形减速标线有效性的联系数μ鱼刺=0. 603,位于评价标准集V1=[0. 6,1],即鱼刺形减速标线有效性很好,该结论与定性评价、模糊综合评价结论完全一致,验证了SPA-ANP理论的可行性,同时能为减速标线有效性评价系统的开发提供借鉴.  相似文献   

6.
为研究高原公路不同天气状况对驾驶人工作负荷的影响,共选定了32名被试驾驶人,包括7名外地驾驶员和25名本地驾驶员,在选定的试验路线上进行了实车试验。在晴天、雨天、雪天、雪天+大雾(能见度5米)的4种不同天气状况下,选取心率变异性RMSSD、SDNN和PNN50值和心率增长率作为驾驶人工作负荷表征指标,研究在高原公路不同天气状况下被试驾驶人工作负荷变化规律。研究结果表明:高原公路不同天气状况对驾驶人的工作负荷有显著的影响,驾驶人工作负荷因天气条件的恶劣程度和海拔高度而增加,道路的天气状况、能见度及海拔高度的共同作用对驾驶员工作负荷影响最大。  相似文献   

7.
为提高海底隧道出入口段行车安全性,研究海底隧道出入口段不同视觉减速标线方案下驾驶员视觉特征变化规律。本文共设置了6种视觉减速标线方案,对26名驾驶员进行了室内驾驶仿真实验,采集了车速、注视点占比、瞳孔直径和察觉距离等数据,通过分析和处理数据判断视觉减速标线的有效性,分别建立了海底隧道出入口段车速与驾驶员瞳孔直径的回归模型,在海底隧道入口段二者呈非线性关系;出口段二者呈线性关系。采用驾驶员问卷调查法对视觉减速标线有效性进行了验证。结果表明:在海底隧道出入口段共设置的6种视觉减速标线方案均对驾驶员视觉特征有显著影响;与其他标线方案相比,白色鱼刺形减速标线设置下驾驶员瞳孔直径、A区域注视点占比、察觉距离和错觉影响最大,有助于驾驶员主动降低车速、提前采取减速措施,保障行车安全。  相似文献   

8.
为减缓汽车通过高速公路振动减速标线时悬架的振动,构建了汽车悬架模型与振动减速标线-车速耦合激励模型.以车辆悬架由减速标线激励产生的垂直方向加速度均方根值为评价指标,采用Simulink对车辆以一定速度通过减速标线时的振动激励特性进行了仿真分析.选取镇江市某快速道路长下坡路段的减速标线进行优化前后的对比试验.结果表明,当给定限速值为80 km·h-1,减速标线宽度为1. 0 m时,小型汽车速度下降率为14. 3%;保持其他参数不变,减速标线宽度为1. 4 m时,速度下降率达到21. 4%,同时行驶车辆悬架产生共振现象.参数优化后的振动减速标线明显改善限速效果并提高了驾乘人员的行车舒适性.  相似文献   

9.
道路交通安全问题是一个受各种因素影响的复杂的系统问题,受不同的驾驶员特性、汽车性能、道路条件及环境之间的相互影响。对速度的分析应该从实际的行驶环境出发,结合车辆行驶轨迹和其他事故致因系统分析。通过实车试验的方法对设置纵向减速标线的山区城市道路交叉口路段和未设置标线的对比路段的交通流量、区间速度、驾驶员瞳孔指标和轨迹横向偏移量等试验数据进行采集,再结合山区城市道路交叉口处的交通特性和道路基本参数等数据,分析试验路段的交通流特性、驾驶员生理行为指标和轨迹规律。试验表明:在城市道路交叉口设置纵向减速标线后车辆在试验路段和对比路段的偏移量分布频率最大值为42.62%和38.18%在(0.5,1]区间内;在山区城市道路交叉口段设置纵向减速标线可以提前警告驾驶员控制车速等有利的影响,提高交叉口行驶安全性。  相似文献   

10.
高原长平直线公路汽车行驶安全   总被引:4,自引:0,他引:4  
为了降低高原公路长平直线路段交通事故率,以实地调查和心理认知机理,对国道213线郎木寺至川主寺公路长平直线路段的车辆行驶安全性进行研究,分析了驾驶人在长平直线路段上行车的交通安全认知及行为特性。研究表明:该路段上交通事故多发的主要原因是道路景色单调,高原反应使驾驶人容易疲劳、反应迟钝;道路两侧缺乏明显的参照物,驾驶人对速度判断的准确性受到影响,容易超速行驶;经常有牧群横穿道路,产生横向干扰。通过对长平直线路段的道路景观设计、路肩设置隆声带、路面喷涂视觉减速标线以及在适当的位置设置放牧通道等安全措施,可提高高原长平直线路段的汽车行驶安全性。  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
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。  相似文献   

16.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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