悬挂式独轨列车转向架

论述了一种悬挂式独轨列车转向架结构特征,对关键零部件如构架、驱动装置、牵引悬挂装置、走行轮和导向轮、车体与转向架之间的联接进行了介绍并进行了动力学性能分析,相关指标均满足要求。     

桥梁地震碰撞反应研究与发展

桥梁在地震中的碰撞反应不容忽视,文章综述了国内外桥梁地震碰撞的模拟方法以及各种形式桥梁结构的地震碰撞近期研究进展,归纳了桥梁碰撞的条件和影响因素,介绍了减轻桥梁结构地震碰撞方法和防落梁措施的主要研究成果,并对桥梁地震碰撞反应的进一步研究作了展望。     

佛山地铁魁奇路地下换乘站抗震性能分析

以佛山地铁魁奇路站实际工程为背景,对地下车站进行了结构抗震性能分析。以反应位移法建立了地铁车站二维结构计算模型,求解了地下车站受地震荷载作用下响应结果,并与静力法计算结果进行了对比,以研究地铁车站在地震作用下的内力变化规律。基于Midas GTS NX软件,应用非线性时程分析法,建立了结构和周围土层为一体的整体计算模型,通过模态分析求解了结构体系各阶的自振频率和各阶振型;模拟了地下结构在地震荷载下的动态特性,揭示了地铁车站在地震作用下的位移时程反应及结构整体变形状况。     

高速客车非线性模型动力学分析

本文建立客车动力学的非线性模型,分析各种非线性结构,悬挂参数对车辆动力性能的影响,着重讨论高速车辆的横向稳定性和在轨道随机不平顺激扰下的运行平稳性。本文还应用研究结果优选出适合我国高速铁路运行的车辆参数匹配。     

Periodic Solutions of Periodic Delay Predator—Prey System with Nonmonotonic Functional Response

By using the continuation theorem of coincidence degree theory, sufficient conditions are obtained for the existence of positive periodic solutions of a delayed predator-prey system with nonmonotonic functional response in a periodic environment.     

Field Measurements and Pullout Tests of Reinforced Earth Retaining Wall

In this paper, field measurements and pullout tests of a new type of reinforced earth retaining wall, which is reinforced by trapezoid concrete blocks connected by steel bar, are described. Field measurements included settlements of the earth fill, tensile forces in the ties and earth pressures on the facing panels during the construction and at completion. Based on the measurements, the following statements can be made : ( 1 ) the tensile forces in the ties increased with the height of backfill above the tie and there is a tensile force crest in most ties; (2) at completion, the measured earth pressures along the wall face were between the values of the active earth pressures and the pressures at rest; (3) larger settlements occurred near the face of the wall where a zone of drainage sand and gravel was not compacted properly and smaller settlements occurred in the well-compacted backfill. The results of field pullout tests indicated that the magnitudes of pullout resistances as well as tensile forces induced in the ties were strongly influenced by the relative displacements between the ties and the backfill, and pullout resistances increased with the height of backfill above the ties and the length of ties.     

梁应辰院士谈三峡工程

1引言 今年6月,举世瞩目的三峡工程二期工程完工,三峡工程进入通航发电阶段.作为集政治、经济与交通等因素于一体的重大系统工程项目,该项目的建设无论对交通运输业还是对系统工程界均有着重大影响.为此,本刊特约记者最近专程采访了最早参与三峡工程建设的专家之一、三峡工程质量检查专家组成员、中国工程院梁应辰院士.     

构建海船驾驶专业实践教学体系的建议

本文根据海船驾驶专业教学的职业特点，提出了构建实践教学体系的六个组成部分，并结合航海教学的实际，建议从教学计划、教学投入、实训教师的队伍建设、教学手段和考核评估、实训教材建设等方面推进改革。     

NEW HAUSDORFF DISTANCE-BASED VEHICLE LOCATION

Objective To realize accurate localization of moving vehicles from single monocular intensity image.Methods The new modified Hansdorff distance(M2HD) was adopted, which used dominant points instead of edge maps as features for measuring similarity between image and model projection. Modified simulated annealing (MSA) algorithm was used to find optimum localization parameters. Results M2HD reduces the computational complexity,and improves the matching precision. Furthermore, MSA can fast find global optimum instead of getting into partial one because of its high parallel and robust performance. Conclusion Experiments confirm that the combination of MSA and M^2 HD can effectively localize the vehicles that are changed both in translation and rotation     

Research on the Variable Steering Ratioof Four-Wheel-Steering Vehicle

The steering characteristic of afour-wheel-steering vehicle is numerically simulated for in-depth research of the handling stability offour-wheel steering．The research results show that the deteriorating tendency of the steering stability due to the increase of the vehicle speed is improved obviously in the case of four-wheel steering．The approach of variable steering ratio is discussed.The use of the variable steering ratio can not only raise the steering stability of vechicles at high vehicle speed，but also reduce the dicomfort and steering burden of drivers；and hence is helpful for the subjective evaluation of four-wheel steering vehicles．