基于满意度的多目标约束模糊控制规则库的建立及应用

本文针对难以建模的非线性系统,结合有关满意度优化理论,给出了基于模糊控制系统的多目标搜索规则库的方法,并利用所建立规则采用Mamdani算法来逼近控制问题的最优解。同时把该方法应用在具有强非线性特点的车辆自动驾驶问题上,通过对模糊控制规则的量化细分搜索出车辆自动驾驶的规则库。     

Evolution of the household vehicle fleet: Anticipating fleet composition, PHEV adoption and GHG emissions in Austin, Texas

In today’s world of volatile fuel prices and climate concerns, there is little study on the relationship between vehicle ownership patterns and attitudes toward vehicle cost (including fuel prices and feebates) and vehicle technologies. This work provides new data on ownership decisions and owner preferences under various scenarios, coupled with calibrated models to microsimulate Austin’s personal-fleet evolution.Opinion survey results suggest that most Austinites (63%, population-corrected share) support a feebate policy to favor more fuel efficient vehicles. Top purchase criteria are price, type/class, and fuel economy. Most (56%) respondents also indicated that they would consider purchasing a Plug-in Hybrid Electric Vehicle (PHEV) if it were to cost $6000 more than its conventional, gasoline-powered counterpart. And many respond strongly to signals on the external (health and climate) costs of a vehicle’s emissions, more strongly than they respond to information on fuel cost savings.Twenty five-year simulations of Austin’s household vehicle fleet suggest that, under all scenarios modeled, Austin’s vehicle usage levels (measured in total vehicle miles traveled or VMT) are predicted to increase overall, along with average vehicle ownership levels (both per household and per capita). Under a feebate, HEVs, PHEVs and Smart Cars are estimated to represent 25% of the fleet’s VMT by simulation year 25; this scenario is predicted to raise total regional VMT slightly (just 2.32%, by simulation year 25), relative to the trend scenario, while reducing CO₂ emissions only slightly (by 5.62%, relative to trend). Doubling the trend-case gas price to $5/gallon is simulated to reduce the year-25 vehicle use levels by 24% and CO₂ emissions by 30% (relative to trend).Two- and three-vehicle households are simulated to be the highest adopters of HEVs and PHEVs across all scenarios. The combined share of vans, pickup trucks, sport utility vehicles (SUVs), and cross-over utility vehicles (CUVs) is lowest under the feebate scenario, at 35% (versus 47% in Austin’s current household fleet). Feebate-policy receipts are forecasted to exceed rebates in each simulation year.In the longer term, gas price dynamics, tax incentives, feebates and purchase prices along with new technologies, government-industry partnerships, and more accurate information on range and recharging times (which increase customer confidence in EV technologies) should have added effects on energy dependence and greenhouse gas emissions.     

公路空间视距计算方法与检测技术

为了精确计算公路在三维空间中的实际视距,提出了空间视距的概念,通过延伸应用空间两点通视原理,建立了空间视距计算和分析的数学模型。基于计算机仿真技术开发出对空间视距的实时检测技术,通过将设计视距、运行视距和空间视距3种视距对比分析,给出了发现视距不足的方法。与早前的视距计算方法和研究相比,该方法对正常路面、行车道空间视距计算准确,能够计算和分析公路路侧附属设施对视距的影响,为公路几何设计和安全评价提供了依据。     

基于DSP的嵌入式驾驶疲劳监测系统研究

为了进行有效的、实时的、非接触式的驾驶员疲劳检测,采取NHTSA和FHWA推荐的非接触式疲劳检测方法PERCLOS,利用TI公司的专用图像处理DSP芯片TMS320DM642,构建了车载的基于DSP的嵌入式驾驶疲劳监测系统。首先使用肤色模型算法迅速定位人脸,然后利用累积差分帧和Hough变换等实时图像处理技术来检测、跟踪眼睛,分析眼睛的状态和提取眼睛的特征参数,计算PERCLOS值、判断疲劳程度并采取报警或其他措施。试验结果表明,系统的算法简单、快速、鲁棒性强。     

智能车辆安全辅助驾驶技术研究近况

论述了安全辅助驾驶技术的研究现状、研究的必要性以及研究进展。安全辅助驾驶技术包括车道偏离预警与保持、前方车辆探测及安全车距保持、行人检测、驾驶员行为监测、车辆运动控制与通讯等。分析了各种传感器的优缺点及其在实际应用过程中存在的问题,基于单一传感器不能很好地解决安全辅助驾驶技术可靠性和环境适应能力的要求,应结合激光雷达技术解决图像模糊问题,利用红外传感器增强机器视觉识别的可靠性,未来的安全辅助驾驶技术应该采取多种传感器融合的技术,结合毫米波雷达和激光雷达系统具有深度测量精确的特点,将极大的推动汽车安全辅助驾驶系统的应用和推广。     

隧道盾构机进出洞施工技术

盾构的进出洞工序是盾构法建造隧道的关键工序。该文阐述了盾构进出洞施工的重要性,介绍了稳定正面土体、基座及后座的设置、洞口间隙的密封等施工技术。     

无证驾驶自动查处系统的设计与探讨

文章结合现有的无证驾驶查处方式带来的问题和弊病,基于智能交通系统的相关技术,介绍了无证驾驶自动查处系统功能模块的设计、安装及关键技术,为无证驾驶系统的研发提供参考。     

汽车车架动特性分析及应用

应用大型结构分析软件ＳＡＰ５Ｐ，对某车架者了有限元动态分析和实验模态分析，通过分析所提供的信息，对某客货车在使用中发生的故障进行了诊断，提出了相应的改进措施，从而使该车具有更好的动态性能。     

驾驶行为研究模拟舱实验整体方案

在介绍AutoSim模拟舱的基本组成、功能的基础上，从交通系统组成的人、车、路的角度，提出了利用驾驶模拟舱进行驾驶行为研究的参数选择、数据库的结构、场景定制等关键技术，并提出了可行的技术路线和实验方案。     

液压驱动车辆的反拖制动性能研究

对液压驱动车辆长下坡制动的性能进行了试验和理论分析，研究泵排量对发动机和液压系统在下坡制动中的影响。对提高液压驱动车辆下坡安全性，为液压驱动车辆合理安排发动机和液压系统制动能力，提高反拖制动性能起到积极作用。