双车道公路运行速度协调性评价相关指标取值

运行速度协调性是评判道路空间几何线形设计的重要指标,而期望速度和加(减)速度又是获得运行速度的关键因素.通过分析我国《公路项目安全性评价指南》(JTG/T B05-2004)与IHSDM的运行速度预测结果,对不同期望速度下的预测结果进行欧氏距离检测,确定较合理的期望速度取值范围;对《公路项目安全性评价指南》中加速度取值参照IHSDM修正,确定更合理的加(减)速度值.结论对指导和改进我国双车道公路运行速度协调性评价相关指标的选取具有一定的理论意义和实用价值,可进一步有效改善协调性不良路段、特别是气候不良条件下道路交通的安全性.     

公路弯坡路段线形设计

根据动力学原理，对汽车在弯坡路段上的运行状态及行车安全性进行了分析。认为弯坡路段之所以成为车辆运行安全隐患的原因是由于设计速度与车辆实际运行速度不协调造成的，在弯坡路段的线形组合设计中应根据车辆的实际运行速度选用技术指标。利用Matlab绘制出在不同设计速度下，坡长、坡度与速度的关系图及“速度与半径的关系图”，为设计公路在弯坡路段的线形组合中合理选取技术指标提供了依据。     

微观仿真软件在公路安全性评价中的应用

现有公路安全性评价方法从公路线形几何条件、运行车速协调性等方面进行评价,是静态和局部的评价方法.利用微观交通仿真进行动态全局评价,不仅可以对公路线形实现连续评价,而且可以将驾驶行为、车辆类型比例、交通流量考虑在内,更加综合、全面地对公路安全性进行评价.以重庆长寿至梁平高速公路安全性评价为例,对提出的新方法与传统方法进行了验证和对比分析.     

广梧高速公路河口至平台段施工图设计安全性评价

针对广梧高速公路河口至平台段施工图设计进行安全性评价．根据《公路项目安全性评价指南》提出的评价内容,结合项目实际,通过对运行速度协调性及线形设计指标进行分析研究,结合路基、路面、桥梁、隧道、互通立交、交通工程、沿线设施以及服务区的安全性评价,按照“分车道、分车型、分路段”的原则,提出了限速要求,对影响该项目运营安全性的主要因素进行了分析,并针对评价路段可能存在的交通安全问题提出了交通工程对策措施．     

基于运行车速的公路线形设计质量评价

速度因素在公路交通事故中占有相当的比重 ,而线形是决定车辆实际运行车速的基础 .通过对车辆运行特征的实地观察和运行车速的现场观测 ,标定了车辆运行车速和加速度与公路线形之间的关系模型 .从行车安全的角度出发 ,将线形单元间运行车速和加速度的变化量作为线形质量的评价标准 ,建立了线形质量评价模型 ,用以进行公路线形设计质量的定量评价 .     

论公路路线运行速度协调性的安全设计与分析

根据某一级公路设计阶段平、纵面线形的设计资料,在计算运行速度中考虑美国道路通行能力手册(2000)中自由流速度的影响因素,对计算的运行速度进行折减,使得计算结果更接近实际运行速度值.该文运用运行速度协调性分析及设计速度与运行速度协调性分析对线形设计的安全性进行了分析,有效地发现设计中道路线形存在的问题,并将存在的安全隐患在设计阶段中消除,从而完善了道路设计,提高了设计道路的安全性水平.     

连续长大下坡路段大货车运行速度预测模型

针对既有线形一致性评价方法未考虑连续长大下坡道路特性的问题,利用10个高速公路连续长大下坡路段的95个特征断面运行速度观测数据,分析了大货车运行速度与坡长、平均纵坡和曲率的关系,建立了大货车运行速度与车辆驶离连续长大下坡起点的距离、车辆至连续长大下坡起点的平均纵坡的关系模型,提出了基于大货车运行速度的连续长大下坡路段线形一致性评价方法. 研究结果表明,提出的模型反映了连续长大下坡路段大货车的运行速度特征,可为高速公路连续长大下坡路段路线安全设计和线形一致性分析提供理论支撑.     

关于公路路线线形“协调性设计”的探讨

在公路路线设计中,线形的协调性经常被设计人员所忽视,设计计算时生搬硬套公路路线设计规范,设计出的路线虽然满足路线设计规范,但实施后经常出现"死亡路段"、"魔鬼路段"等现象,究其原因是路线设计中的线形协调性处理不好所造成的。本文采用运行车速及包括时间在内的四维空间连续曲线的设计理论对路线线形的协调性设计进行了初步的分析和研究。     

基于高速公路空间几何特性的线形协调性设计评价

为对高速公路线形协调性设计进行有效的评价和指导,利用驾驶模拟和实车试验获取车辆运行数据,提出一种基于线形空间几何特性参数拟合的协调性设计评价模型,并给出了指标选用及优化措施。首先,分析了优先进行线形协调性设计的特征指标,以曲率k和挠率τ作为描述高速公路线形空间几何特性的的特征参数。其次,结合驾驶模拟实验和实车试验,通过多元非线性拟合建立一般路段线形设计协调性与曲率差Δk、挠率差Δτ的二元多项式评价模型,并通过调整横断面和安全设施信息对模型进行修正。结果表明,该模型能较好地反映线形指标、横断面信息、交通安全设施与车辆运行状态间的作用关系,为高速公路线形协调性设计和应用研究提供指导。最后,通过反推Δk、Δτ取值范围,提出了指标选取的依据和优化措施。     

面向公路线形评价的驾驶人方向控制模型

为了客观地评价公路线形设计成果,基于驾驶人轨迹预瞄理论,结合汽车的实时状态拟合预瞄轨迹,考虑汽车转向传递特征和操作的滞后性,建立了驾驶人方向控制模型,并在VB 6.0环境下编制了程序,进行了车辆运行的仿真试验。结果表明:所建模型可计算汽车行驶时的横向加速度和方向盘转角,能较好地反映公路的行车舒适性和安全性,并可用于公路线形的评价;汽车初始速度为0和54 km/h的运行结果仅在起始路段有显著差别;在汽车运行稳定后,横向加速度和方向盘转角的变化与平面线形的变化基本一致。     

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.     

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.     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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.