高速列车座椅间距对乘员二次碰撞伤害的影响

为研究高速列车座椅间距对乘员碰撞伤害的影响,在欧洲列车乘员伤害仿真、试验和评价标准的基础上,参考我国列车客室设施与布置,采用MADYMO Hybrid Ⅲ 50％假人,建立高速列车碰撞事故乘员二次碰撞仿真模型．通过仿真分析比较不同座椅间距对乘员伤害的影响．研究表明,合适的座椅间距能减小乘员的HIC（Head Injury Criterion）值和碰撞的相对速度,从而减小乘员伤害概率．     

单一滑动窗口下的字级位平面编码研究与实现

位平面编码（BPC）是JPEG2000编码器中EBCOT的重要组成部分。为了解决BPC实现的低效问题,提出了一种改进的并行硬件结构来实现字级位平面编码算法。对编码通道预测和上下文形成的流水线并行处理技术进行了研究,实现了在一个时钟周期内对一个条带列的所有位样本并行编码。当样本系数被顺次编码时,包含在每个位平面中的三个通道编码在一次扫描中完成。该系统结构已经通过ModelSim实现和TSMC综合。结果表明,该结构可以有效减少硬件成本,并提供高速的数据处理能力,适合实时图像和视频的应用。     

基于位平面图像与2DMSLDA的单样本人脸识别

在进行单训练样本人脸识别时,基于每人多个训练样本的传统人脸识别算法效果通常不太理想。尤其是基于Fisher线性鉴别准则的一些方法,由于类内散布矩阵为零矩阵,根本无法进行识别。针对以上问题进行了分析研究,提出了一种新的样本扩充方法,即：采用位平面图像分解法,将每幅样本图像分解为8幅,进而通过各种合成策略构造多幅样本图像。使用一种更加稳定的二维最大散度差线性鉴别分析方法（2DMSLDA）对上面获得的新样本图像进行特征抽取。在ORL国际标准人脸库上进行的实验表明了所提算法的可行性和有效性。     

应用螺旋理论对并联机器人形位的分析与综合

采用螺旋理论对并联机器人的约束与运动问题进行了分析和总结. 在各种约束存在条件下,分析了刚体平台相应的运动轨迹形式,为今后对多刚体的形位分析提供了可行的理论依据．     

双手爪爬杆机器人对杆件的位姿检测与自主抓夹

为实现5自由度平面构型的双手爪爬杆机器人Climbot对目标杆件的自主抓夹,提出一种基于2D激光扫描测距仪的杆件位姿检测和自主抓夹方法.首先根据Climbot的平面构型,给出了机器人在两圆杆间过渡时的特殊位姿约束条件.再摆动夹持器使得安装在上面的激光传感器可以用扫描的方式获取目标杆件上若干中心点位置,并将其拟合出杆件的空间直线方程,即杆件位姿.并基于直线方程,规划出了满足过渡约束条件的自主抓夹运动.最后通过实验分析了杆件中心点位置的检测误差,以及所求杆件位姿相对于实际杆件和Climbot夹持器坐标系的角度误差.相对于杆件尺寸以及夹持器张合度,上述误差均可接受.本文方法能够准确地检测目标杆件的位置信息,并给出合理的抓夹运动规划.     

Rail passenger perceptions of risk and safety and priorities for improvement

Recommendation 60 of the Ladbroke Grove rail inquiry stated that “comprehensive market research in regard to safety related measures should be carried out in order to take account of the views of informed passengers” (Cullen 2001, p. 235). In response, the Rail Safety and Standards Board Limited (RSSB) commissioned a survey of railway passengers nationwide, to investigate passenger perceptions of risk and safety at stations, on platforms and on trains, and to research passenger preferences for implementing safety interventions. Following qualitative interviews conducted with rail travellers, two separate questionnaires were designed and piloted. Each survey was administered face-to-face at 15 hub railway stations nationwide, according to a quota sample, and respondents were asked to return completed questionnaires by post. The overall response rate was approximately one-third. The results of the safety and risk survey provide a valuable indicator of passenger perceptions of risk, especially when compared to quantitative assessments of actual risk. The findings suggest that the relationship between perceived and actual risk is not particularly strong. The data from the passenger preferences questionnaire were analysed using conjoint techniques, and the results provide information on passenger preferences and priorities for improvement. The results are likely to be of value to the railway industry in allowing passenger preferences to be taken into account when implementing safety interventions.     

改进的汽车安全气囊静态点爆仿真方法

对主驾驶安全气囊静态点爆的前期阶段进行仿真,并结合实验进行验证.详细描述气囊压缩折叠方法和气囊压缩后的质量要求,分析影响仿真精度的因素并提出验证这些因素准确性的方法.结果表明测量支反力是验证气囊在展开过程中对周围零部件作用力的产生以及零部件间力传递过程是否准确的有效途径.     

Altera业界首推40nm FPGA期待占据市场主导地位专访Altera亚太区副总裁兼董事总经理Erhaan Shaikh先生

<正> Ahera 在中国深圳、杭州、北京三地主办 SOPC World 2008,《电子技术应用》(AET)作为唯一的媒体对此次活动进行跟踪报道。针对目前一些热点问题及 Altera 的发展策略等,我们有幸在杭州对 Altera 亚太区副总裁兼董事总经理 ErhaanShaikh(柯汗青)先生进行专访。AET:您觉得与去年相比,今年贵公司及整个行业有什么改变吗?Shaikh 先生:与去年相比,     

基于PowerPC的汽车安全气囊控制系统设计

为减小驾驶员和乘员的伤害,安全气囊系统已成为重要的安全设备。随着安全气囊数量的增多,对ECU控制器的实时性、运算速度等要求也越来越高,同时为了增加点火算法的抗干扰性及稳定性,设计了一款以32位微处理器MPC5634M为主芯片的安全气囊控制系统。该系统包括TLE6710Q集成芯片,可实现电源管理和点火控制,增加系统稳定性,采用MMA6825BKW加速度传感器检测车身双向加速度,软件编程通过可变窗宽移动窗积分算法来判断是否需要点爆安全气囊。实验结果表明,该控制系统有效解决了误点火与漏点火的问题,从而提高点爆的准确率与稳定性。     

The effects of seat width,load factor,and passenger demographics on airline passenger accommodation

Abstract

The objective of this work is to demonstrate a method for examining the competing effects of secular trends in body size, seat size and configuration, and the increased load factor of aeroplanes. The method uses statistical modelling and virtual fit testing to provide a flexible environment for exploring the impact of various parameters on passenger accommodation. A case study demonstrates the method by exploring the effect of seat width on the accommodation of US civilians (based on seated hip breadth). The case study demonstrates that recent trends of decreasing seat widths and increasing load factors lead to higher disaccommodation. Based on anthropometry and virtual fit, women are also shown to be disproportionately disaccommodated compared to men.

Practitioner summary: Airlines are reducing seat width at the same time that individuals worldwide are getting larger. Flights are increasingly crowded, with load factor at a record high. This paper explores the effects of seat width on passenger accommodation under several scenarios involving load factor, demographics, and passenger seating allocation strategies.     

基于导叶位置数据分析的刘家峡水电厂导叶立面间隙调整方法改进

在水电厂水轮机检修过程中,水轮机导叶立面间隙调整是一项重要而精细的工作,其主要目的是将水轮机24片矩形导叶两两相靠,调整为一个密不透水的圆筒状。传统导叶立面间隙调整方法虽然能满足调整完成后两两导叶立面间隙为零的技术要求,但因缺乏精确的反馈量和监视量,调整过程费时费力,同时可能造成导叶之间压紧程度不一的现象,对后续调整产生一定影响。通过采集机组检修前导水机构各项数据,导入三维建模软件进行精确建模,在模型中进行多项初始条件下进行水轮机导叶立面间隙模拟调整,并与检修前数据比较,得出该检修状态下导叶的标准位置。在现场实际调整过程中,根据不同水轮机导叶立面间隙分布情况、机组检修级别,结合导叶标准位置提出差异化水轮机导叶立面间隙调整策略,极大提高了水轮机导叶立面间隙[3]调整效率和精度,保证了机组运行安全性。     

考虑非线性轮轨关系的高速客车横向动力学研究

随着列车运行速度的提高,高速客车横向稳定性一直是近年来研究的热点. 建立 9 自由度半车数学模型,利用数值方法对该系统的横向稳定性与分岔问题进行了研究,得到车辆系统发生蛇行运动时的临界速度及分岔后各运动状态的转变过程. 结果表明系统超过临界速度后会发生复杂的动力学行为,包括单周期、两周期、混沌运动等,并且由对称向不对称,最后再向对称运动转化.     

基于系统动力学的大型客机供应链质量管控契约优化

研究再制造视角下我国大型客机供应链质量控制问题.根据大型客机制造三级供应链中供应商、主制造商及销售商的运作特点,刻画三者内在的动力学参数特征;构建基于质量奖惩和成本分摊的供应链控制契约,建立主制造商质量控制契约协调优化规则;设计大型客机供应链质量控制仿真的系统动力学模型;以液压系统为例仿真分析管控策略,并通过对比分析得出管控策略的有效性.     

Effects of vertical vibration on passenger activities: writing and drinking

Abstract

The efficiency of training programmes in handling designed to prevent injuries has rarely been demonstrated by studies in the workplace. This study aimed to identify factors that may favour or inhibit the application of safe handling principles by paramedics performing full-body transfers of patients from a stair chair to a stretcher. In an observational field study, handling methods used in 45 patient transfers from a stair chair to stretcher were characterised. Principles concerning the physical environment seem to be applied frequently, but those applicable during the transfer are neglected. Principles taught during training may not be applied due to the physical constraints of the workplace and the underestimation of risk exposure. The results suggest that training should be enhanced, not by focussing on handling techniques but by focussing on compromise and the capacity to adapt work techniques based on the working context and the team-mate.