轻型载货汽车车外噪声分析与控制

用声强扫描法对国产某轻型载货汽车车外噪声源进行了识别,确定了其车外主要噪声源。开发了材料声学特性测量系统,并对多种车用吸声、隔声材料进行了测试与分析。根据被试轻型载货汽车车外主要噪声源的特性合理地选择吸声、隔声材料和噪声控制方案,对其进行了降噪处理。通过对降噪前、后该车车外噪声进行测试分析表明,采取降噪措施后,被试车辆车外动态加速噪声由84dB(A)下降到78dB(A),能够满足国家标准GB1495—2002对该类车辆车外动态加速噪声限值的要求。     

燃料电池轿车车内噪声特性试验分析

在半自由场消声室内四轮转毂试验台上对燃料电池轿车进行了声振特性测试,采集了不同车速工况下车内噪声信号及运动部件的振动加速度信号。分析了不同车速工况下车内噪声的分布状况及主要频率成分。通过信号分析表明,车内噪声来源于驱动电机总成和燃料电池系统中的氢泵、风机,产生的噪声通过空气直接传到车内,同时引起车身板件振动并向车内辐射噪声。根据样车的结构特点提出了减振降噪措施。     

城市轨道交通中个人导向方法研究

文章运用层次分析的方法来阐述个人导向功能的实现原理,提出了利用现阶段飞速发展的移动通信体技术,设计一种应用在城市轨道交通中具有个人导向功能的移动通信体,以改善城市轨道交通中个人导向功能薄弱的现状。     

声全息方法识别汽车运动噪声

本文提出利用声全息原理，对运动状态下的汽车噪声源进行识别的方法，它能够用来分析汽车在高速运动过程中发动机的噪声，轮胎噪声和空气动力学噪声，通过低速和高速实验表明该方法是一种有效的方法，能够快速，准确识别运动车辆的噪声。     

CAN总线在雪铁龙C5轿车中的应用及检修

雪铁龙C5轿车是法国雪铁龙公司的新一代主流产品。介绍了应用在雪铁龙C5轿车上的CAN数据总线的特点、组成与结构，CAN数据总线的传输原理与过程，以及BSI智能服务器(网关)的组成与功能。另外，介绍了CAN网络的检修。     

交互劳务代数分配法实际操作研究

本文研究辅助生产部门交互劳务代数分配法的实际操作问题,解决了该方法的辅助生产费用分配表的设计、联立方程组的建立和帐务处理等问题。笔者提出的实际应用程序可操作性强。     

The best of times and the worst of times: A new best–worst measure of attitudes toward public transport experiences

Attitudes play an important role in determining individual transit behaviour and the measurement of attitudes is relied on by public transit authorities’ world over. Given their role in behaviour and policy making, the accurate measurement of attitudes is of critical importance. Traditional satisfaction scales are prone to bias and on their own they are only a partial measure of attitudes. Given that satisfaction scales have been used to assist with large scale transport infrastructure investment decisions, to aid policy makers examining reactions to alternative policy changes and reform, and to measure the success of new initiatives, deriving robust satisfaction scales should be of critical importance. This paper introduces a dual version of best–worst scaling as an alternative measure of satisfaction. Best–worst scaling is free of the biases inherent in traditional response scales and is ideal for handling the comparative evaluation of large amount of attributes, particularly those which are inherently qualitative. The paper makes a further innovative contribution by proposing a model structure for the joint estimation of satisfaction and importance. Our model shows a better delineation between the attributes used to measure attitudes towards bus use and a more detailed understanding of the relationship between importance and satisfaction; enabling transport operators to better understand what counts most and assess their performance.     

Optimization models for differentiating quality of service levels in probabilistic network capacity design problems

This paper develops various chance-constrained models for optimizing the probabilistic network design problem (PNDP), where we differentiate the quality of service (QoS) and measure the related network performance under uncertain demand. The upper level problem of PNDP designs continuous/discrete link capacities shared by multi-commodity flows, and the lower level problem differentiates the corresponding QoS for demand satisfaction, to prioritize customers and/or commodities. We consider PNDP variants that have either fixed flows (formulated at the upper level) or recourse flows (at the lower level) according to different applications. We transform each probabilistic model into a mixed-integer program, and derive polynomial-time algorithms for special cases with single-row chance constraints. The paper formulates benchmark stochastic programming models by either enforcing to meet all demand or penalizing unmet demand via a linear penalty function. We compare different models and approaches by testing randomly generated network instances and an instance built on the Sioux–Falls network. Numerical results demonstrate the computational efficacy of the solution approaches and derive managerial insights.     

新罗海上军事力量与古代东北亚国际关系

新罗海上力量,在隋唐东征中兴起,参与了半岛统一的历史重任,使得东北亚地缘政治平衡得以重建,扭转了历史走向。新罗海上力量经历了8世纪的首度衰落之后,恰逢东亚各国中央集权的衰落,东北亚国际海面出现前所未有的乱象。张保皋海权活动填补海上权力的空白,促进了东北亚海上丝绸之路的新繁荣。张保皋的海权活动目的是促进国际和平往来,而非称雄争霸,日本也因此获取海上便利,而唐朝宽容默许张保皋的活动。张保皋发展海权的成果最终被扼杀了,以致东北亚的海上局面出现再次失序的苗头。在新罗结束期的乱局中半岛海上力量再次以相当规模出现。     

Understanding the impacts of mobile phone distraction on driving performance: A systematic review

The use of mobile phones while driving—one of the most common driver distractions—has been a significant research interest during the most recent decade. While there has been a considerable amount research and excellent reviews on how mobile phone distractions influence various aspects of driving performance, the mechanisms by which the interactions with mobile phone affect driver performance is relatively unexamined. As such, the aim of this study is to examine the mechanisms involved with mobile phone distractions such as conversing, texting, and reading and the driving task, and subsequent outcomes. A novel human-machine framework is proposed to isolate the components and various interactions associated with mobile phone distracted driving. The proposed framework specifies the impacts of mobile phone distraction as an inter-related system of outcomes such as speed selection, lane deviations and crashes; human-car controls such as steering control and brake pedal use and human-environment interactions such as visual scanning and navigation. Eleven literature-review/meta-analyses papers and 62 recent research articles from 2005 to 2015 are critically reviewed and synthesised following a systematic classification scheme derived from the human-machine system framework. The analysis shows that while many studies have attempted to measure system outcomes or driving performance, research on how drivers interactively manage in-vehicle secondary tasks and adapt their driving behaviour while distracted is scant. A systematic approach may bolster efforts to examine comprehensively the performance of distracted drivers and their impact over the transportation system by considering all system components and interactions of drivers with mobile phones and vehicles. The proposed human-machine framework not only contributes to the literature on mobile phone distraction and safety, but also assists in identifying the research needs and promising strategies for mitigating mobile phone-related safety issues. Technology based countermeasures that can provide real-time feedback or alerts to drivers based on eye/head movements in conjunction with vehicle dynamics should be an important research direction.