汽车悬架优化设计中的近似模型方法及其应用

针对目前汽车悬架设计中存在的问题,提出了一种基于近似模型和遗传算法的高效全局优化设计方法.使用Kriging方法重构目标函数,建立了悬架运动学分析的近似模型;采用了CVT试验设计以确保参数空间中样本点分布的均匀性;在重构出的目标函数基础上采用遗传算法进行寻优.以双横臂式前独立悬架为例,以车轮接地点侧向最大滑移量为优化目标进行了优化设计.结果表明,采用该设计方法可缩短设计周期及降低设计成本.     

基于CAN总线的汽车车身网络系统开发

介绍应用CAN总线开发的汽车车身网络系统。该系统具有车身电器网络化控制、模拟量采集、信息显示等功能,设计了可以保持汽车传统操作方式不变的人机接口,阐述了系统的开发思想、硬件设计、通讯协议及软件设计,总结了系统开发情况。     

车载以太网SOME/IP在信息娱乐系统的应用

随着汽车智能化和娱乐化的不断发展,传统CAN通讯已经无法满足车载娱乐系统对传输带宽的要求,迫切需求高带宽的新一代车载网络技术及架构。因此,车载以太网应运而生,其高传输速率能够满足现代汽车娱乐系统的音频、视频、云端等数据传输的要求。SOME/IP协议是车载以太网的重要应用层协议之一,掌握SOME/IP的应用方法对车载信息娱乐模块至关重要。     

穿浪双体船迎浪纵向运动和阻力增值CFD不确定度分析

基于RANS方法,对穿浪双体船浪(WPC)迎浪纵向运动和阻力增值进行了数值分析,并对计算数值进行了验证和确认,证明了静水和波浪中运动计算结果的可靠性。通过计算结果与模型试验数据的对比发现,RANS方法在各种波长中预报精度均较高,验证了该方法的有效性。     

Identifying travel mode with GPS data

Travel mode identification is an essential step in travel information detection with global positioning system (GPS) survey data. This paper presents a hybrid procedure for mode identification using large-scale GPS survey data collected in Beijing in 2010. In a first step, subway trips were detected by applying a GPS/geographic information system (GIS) algorithm and a multinomial logit model. A comparison of the identification results reveals that the GPS/GIS method provides higher accuracy. Then, the modes of walking, bicycle, car and bus were determined using a nested logit model. The combined success rate of the hybrid procedure was 86%. These findings can be used to identify travel modes based on GPS survey data, which will significantly improve the efficiency and accuracy of travel surveys and data analysis. By providing crucial travel information, the results also contribute to modeling and analyzing travel behaviors and are readily applicable to a wide range of transportation practices.     

印尼雅加达高架简支变连续小箱梁墩顶连接段 受力特性分析

以印尼雅加达收费公路项目为背景,研究印尼高架简支变连续小箱梁墩顶连接段受力特性。通过对墩顶连接段顶板钢束、板厚、隔离段长度、变截面等参数的优化分析,确定了预应力混凝土连接段和钢筋混凝土连接段的最佳构造方案。研究表明,对于预应力混凝土连接段,适当增加预应力钢束数量可减小连接段板顶拉应力;减小板厚有利于降低板顶的拉应力;隔离段长度增大反而会使得连接段上缘拉应力增大;连接段端部采用变截面不利于连接段受力。对于钢筋混凝土连接段,减小板厚是优化钢筋混凝土连接段受力特性的有效措施;隔离长度对连接段弯矩影响较小。     

400000DWT矿砂船总体设计浅谈

从国际铁矿石供求的市场背景出发,详细地阐述了上海船舶研究设计院为铁矿石巨头巴西淡水河谷研发和设计的被誉为"中国最大型"的400000DWT超大型矿砂船的总体设计.     

边坡锚固预应力传递规律的离心模型试验研究

以国道G323改造工程K617段花岗岩残积土边坡为原型,进行了离心模型试验,得出预应力在坡体内不同位置引起的土压力变化和预应力自坡面向坡体内的传递规律。     

日本交通安全对策的借鉴与启示

尽管日本的机动车保有量和交通事故数量高于我国,但日本交通事故死亡人数远远低于我国。论文在综合介绍日本道路交通安全对策的基础上,将交通事故发生数量和交通事故造成的死亡数量与日本的乘用车保有量进行回归分析,并以虚拟变量的形式考虑了交通安全相关对策对交通事故量和死亡人数的影响。从分析结果可以看出,交通事故的发生量和死亡人数与乘用车的保有量有很大相关性,但是交通安全的相关对策对交通事故的降低和死亡人数的减少有重大影响,这对我国交通安全管理措施的制定和完善提供了积极的借鉴和启示。     

Pedestrian crosswalk overflow violation in China: Characteristics and countermeasure

The phenomenon that pedestrians do not walk in the crosswalk during pedestrian green is defined as overflow violation, which is illegal but common. Broadly varying crossing positions at far-side cross-section may result in widely distributed conflict points with left-turning and right-turning vehicles, which may cause the occurrence of severe conflicts. This paper proposes a model to estimate the overflow pedestrians’ crossing positions at the far-side cross-section of signalized crosswalk, which enables us to better understand pedestrian overflow violation behavior and finally facilitate their safety. After analysis, the intersection geometry and destination are determined as the critical factors causing pedestrians to overflow. And then, Weibull distribution is employed to describe the stochastic characteristics of overflow pedestrians’ crossing position distribution at the far-side cross-section. A crossing position distribution model which takes the crosswalk length, width and distance between crosswalk and destination into account is developed. The established model is validated by comparing the observed pedestrian crossing positions with the estimated crossing positions. The validation results suggest that the established model is capable of being adopted to estimate the overflow pedestrians’ crossing positions at far-side cross-section. Based on the model, countermeasure for overflow violation can be put forward to prevent pedestrians from walking outside the crosswalk.