结合消费行为分析的高速公路服务区功能定位研究

为合理定位高速公路服务区的功能属性,在充分调研出行者在高速公路服务区的消费需求及消费习惯的基础上,结合服务区消费行为分析,提出服务区"经济融合、功能复合、模式多元"的发展定位思路和融合"服务区+"的功能定位模式,并以山西省高速公路服务区为例进行实证分析。结果表明,山西省服务区出行者消费水平主要集中在50元以内,消费需求中连锁餐饮和特色购物的需求最大,占比超40%,服务区总体满意度为3. 6,介于一般和比较满意之间。     

Methodology for kinematic cycle characterization of vehicles with fixed routes in urban areas

This paper analyses the driving cycles of a fleet of vehicles with predetermined urban itineraries. Most driving cycles developed for such type of vehicles do not properly address variability among itineraries. Here we develop a polygonal driving cycle that assesses each group of related routes, based on microscopic parameters. It measures the kinematic cycles of the routes traveled by the vehicle fleet, segments cycles into micro-cycles, and characterizes their properties, groups them into clusters with homogeneous kinematic characteristics within their specific micro-cycles, and constructs a standard cycle for each cluster. The process is used to study public bus operations in Madrid.     

Risk assessment based on driving behavior for preventing collisions with pedestrians when making across-traffic turns at intersections

Traffic accident statistics in Japan show the necessity of preventing vehicle-on-pedestrian accidents. If the risk of a vehicle colliding with pedestrians could be evaluated in advance, driver-assistance systems would be able to support drivers to avoid potential collisions. Here, features of driving behavior and methods for assessing the risk of collision were investigated for a right turn at an intersection in left-hand traffic, which is a typical vehicle-on-pedestrian accident scenario. The results showed that pedestrian-collision risk can be evaluated from how the driver slows the vehicle and where the driver looks while turning during the maneuver. Moreover, pedestrian-collision risk could be predicted based on driving behavior upon commencement of steering when making an across-traffic turn.     

邻车切入工况下前撞预警系统的驾驶人依赖特性

为提升邻车切入工况下的行车安全,基于驾驶模拟实验平台,研究了驾驶人对前撞预警系统的依赖特性评价方法以改进预警系统的设计。以预警时机(即碰时间TTC)为研究变量,采集了12名驾驶人的实验数据,以制动依赖指数、次任务评分为2项客观指标,以危险度评分、信任度评分为2项主观指标,建立了评价体系模型,实现了对驾驶人系统依赖程度的量化评价。设计了L9(34)正交实验,建立了依赖特性评价回归模型。结果表明:预警时机(TTC)对依赖特性的影响最为显著:过晚的预警时机(TTC=2.4 s)降低系统的有效性;过早的预警时机(TTC=1.2 s)易导致驾驶人对系统过度依赖。因而,适度推迟预警时机(TTC=1.8 s)可以抑制依赖性的产生,提升系统的安全性。     

行车液压取力交流发电系统可行性研究

本文对行车液压取力交流发电系统的可行性进行了分析,并结合实例进行了验证。     

电动乘用车的能量密度及续驶里程

总结《免征车辆购置税的新能源汽车车型目录》(第一批到二十九批)中的电动乘用车相关数据,重点分析近6年电动乘用车的电池能量密度、整车能量密度及续驶里程的变化,通过梳理分析,总结其规律及变化趋势。     

Comparative analysis of the energy consumption and CO2 emissions of 40 electric,plug-in hybrid electric,hybrid electric and internal combustion engine vehicles

This paper analyses the results of the Royal Automobile Clubhallo’s 2011 RAC Future Car Challenge, an annual motoring challenge in which participants seek to consume the least energy possible while driving a 92 km route from Brighton to London in the UK. The results reveal that the vehicle’s power train type has the largest impact on energy consumption and emissions. The traction ratio, defined as the fraction of time spent on the accelerator in relation to the driving time, and the amount of regenerative braking have a significant effect on the individual energy consumption of vehicles. In contrast, the average speed does not have a great effect on a vehicles’ energy consumption in the range 25–70 km/h.     

脑电技术在驾驶行为分析中的应用

介绍了脑电波的发生原理、脑电波与人心理变化之间的关系以及脑电波的检测方法;最后讨论了利用脑电技术在分析驾驶行为方面的应用:评价交通安全与研究驾驶疲劳。     

用于低压和高压器件的IGBT的额定过载特性

具有薄n基区和低掺杂场截止层新结构的非穿通绝缘栅双极型晶体管NPT IGBT明显降低了总损耗.特别是场截止概念与挖槽晶体管单元的结合能产生通态电压最小、开关损耗最低、载流子浓度近乎理想的器件.这种概念在600V～6.5 kV以上的IGBT和二极管中得到了发展.当折衷性能和总耐量与电压和电流额定值无关时,低压器件的开关特性与高压晶体管(VBr＞2 kV)的处理方法不同.采用HE-EMCON二极管和高达1 700 V的新型场截止NPT IGBT,几乎不受开关性能的限制,不过,需考虑的是外部栅极电阻必须取确定值.相比低压晶体管,高压器件的电流密度较低,因而高压二极管和IGBT中的"动态"电场强度更临界.     

一类积微分方程组的解及莫渐近性质

本文讨论了二维人口算子A B的谱特性,以及由它生成的C_0-半群的性质,导出了相应的积分微分方程组的解及其渐近性质。