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421.
徐林生 《重庆交通大学学报(自然科学版)》2005,24(5):18-20,24
从公路隧道开挖围岩变形位移历时曲线的特征出发,采用灰色Verhulst生物增长模型来预报其围岩变形的趋稳位移,用Verhulst反函数模型来预报围岩变形的突发失稳时间;实例研究结果表明,它们都具有较高的预报精度. 相似文献
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日本城市轨道交通应用系统模式 总被引:1,自引:0,他引:1
简述了日本城市轨道交通系统的发展概况,介绍了该国的几种主要城市轨道交通模式,由此对中国的城市轨道交通模式选择提出了几点建议。 相似文献
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Crash Prediction Models (CPMs) have been used elsewhere as a useful tool by road Engineers and Planners. There is however no study on the prediction of road traffic crashes on rural highways in Ghana. The main objective of the study was to develop a prediction model for road traffic crashes occurring on the rural sections of the highways in the Ashanti Region of Ghana. The model was developed for all injury crashes occurring on selected rural highways in the Region over the three (3) year period 2005–2007. Data was collected from 76 rural highway sections and each section varied between 0.8 km and 6.7 km. Data collected for each section comprised injury crash data, traffic flow and speed data, and roadway characteristics and road geometry data. The Generalised Linear Model (GLM) with Negative Binomial (NB) error structure was used to estimate the model parameters. Two types of models, the ‘core’ model which included key exposure variables only and the ‘full’ model which included a wider range of variables were developed. The results show that traffic flow, highway segment length, junction density, terrain type and presence of a village settlement within road segments were found to be statistically significant explanatory variables (p < 0.05) for crash involvement. Adding one junction to a 1 km section of road segment was found to increase injury crashes by 32.0% and sections which had a village settlement within them were found to increase injury crashes by 60.3% compared with segments with no settlements. The model explained 61.2% of the systematic variation in the data. Road and Traffic Engineers and Planners can apply the crash prediction model as a tool in safety improvement works and in the design of safer roads. It is recommended that to improve safety, highways should be designed to by-pass village settlements and that the number of junctions on a highway should be limited to carefully designed ones. 相似文献
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为了使路厩预防性养护措施选择与养护时机的确定更加合理.以沥青混凝土路面结构行为方程为基础建立了预防性养护前性能预测模型,并通过引入原路面有效厚度系数与养护措施特征系数建立了预防性养护后性能预测模型;进而简述了基于该模型的效益-费用分析法,应用该方法可以方便准确地确定最佳养护时机和养护措施.该文提出的基于预防性养护的沥青... 相似文献
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