胶粉改性沥青存储稳定性的研究

为改善胶粉改性沥青的存贮稳定性。依据沥青混合料实验规范,选取存储48h后的软化点之差,作为评定标准。通过控制变量的对比分析,对影响胶粉改性沥青存贮稳定性的各种因素进行评估。结果表明,较好的沥青品种,较大的胶粉目数,较低的胶粉掺量,较高的搅拌温度,较长的搅拌时间以及经过高速剪切,均可增加胶粉改性沥青的存储稳定性。     

西安铁路局多经战略装车点建设工作的思考

分析西安铁路局多经战略装车点的基本现状,探讨建设战略装车点面临的机遇和优势及所面临的困难,最后,提出做好战略装车点建设工作的建议。     

Driving behaviour models enabling the simulation of Advanced Driving Assistance Systems: revisiting the Action Point paradigm

In the field of Intelligent Transportation Systems (ITS), one of the most promising sub-functions is that of Advanced Driver Assistance Systems (ADAS). Development of an effective ADAS, and one that is able to gain drivers’ acceptance, hinges on the development of a human-like car-following model, and this is particularly important in order to ensure the driver is always ‘in the (vehicle control) loop’ and is able to recover control safely in any situation where the ADAS may release control. One of the most commonly used models of car-following is that of the Action Point (AP) (psychophysical) paradigm. However, while this is widely used in both micro-simulation models and behavioural research, the approach is not without its weaknesses. One of these, the potential redundancy of some of the identified APs, is examined in this paper and its basic structure validated using microscopic driving behaviour collected on thirteen subjects in Italy. Another weakness in practical application of the Action Point theory is the identification of appropriate thresholds, accounting for the perception, reaction and adjustment of relative speed (or spacing) from the leading vehicle. This article shows that this identification is problematic if the Action Point paradigm is analysed in a traditional way (car-following spirals), while it is easier if the phenomenon is analysed in terms of car-following ‘waves’, related to Time To Collision (TTC) or the inverse of TTC. Within this new interpretative framework, the observed action points can be observed to follow a characteristically linear pattern. The identification of the most significant variables to be taken into account, and their characterisation by means of a simple linear pattern, allows for the formulation of more efficient real-time applications, thereby contributing to the development and diffusion of emerging on-board technologies in the field of vehicle control and driver’s assistance.     

船体外板三维曲面的有效提取

复杂工业环境下不规则曲面的提取方法是水火弯板机器人的重要研究问题之一。本文提出了一种水火弯板机器人复杂曲面提取方法,经过曲面数据采集,加工区域确定,曲面边缘提取,曲面边缘处理,最后根据曲面边缘提取船体外板三维曲面。实验结果表明,该方法在控制处理时间的同时提高精度,缓解点偏差问题,能在海量点云数据下提取出复杂曲面的三维点云数据。