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51.
基于区域生长的道路图像分割技术研究 总被引:1,自引:0,他引:1
对一幅给定的道路图像,首先计算其梯度图像,然后利用HOUGH变换确定粗略道路区,根据灰度直方图全局峰值个数选取区域核心点,采用近邻函数准则聚类算法选取区域生长阈值,结合单一型链接区域生长和质心型链接区域生长作为生长准则进行区域生长,得出道路区的区域描述。 相似文献
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低附着路面条件的EPS控制策略 总被引:4,自引:0,他引:4
低附着路面上,车辆自回正力矩显著降低,传统电动助力转向控制策略不能很好地克服这一不利影响,导致车辆回正性能降低,路感丧失甚至带来驾驶员对车辆的误操纵,或导致车辆不能及时回正;在建立基于整车动力学的电动助力转向系统模型的基础上,经电动机电流和转矩传感器测得转矩值,拟合得到当前路面条件下的自回正力矩,同时通过转向盘转角信息计算理想路面条件下的名义自回正力矩,结合路面估计算法,将被识别的路面附着系数等级分为高、中、低,设计基于路面附着系数的助力电流控制策略和基于时变滑模变结构控制的回正控制策略,仿真结果表明可有效改善车辆在低附着路面上的操纵路感和回正性能。建立基于LabVIEW PXI的电动助力转向(Electric power steering,EPS)硬件在环试验平台,并对控制策略进行试验验证,试验结果和仿真结果基本一致。 相似文献
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Taxis experience a higher risk of a motor vehicle crash partly because of their much higher levels of exposure on the roads. Although several studies have been conducted to examine the factors associated with the frequency and severity of taxi collisions, little research has been conducted to examine the differences in the factors associated with owner taxis and non-owner taxis. This study finds that collisions involving non-owners are more likely to be associated with poor or risky driving behaviors than collisions involving taxi vehicle owners. This result is consistent with the economic principles of moral hazard and adverse selection. Hence, policy makers responsible for traffic safety, taxi regulation or taxi operations should consider measures to reduce these market inefficiencies and improve the safety of not only taxi drivers but all road users. 相似文献
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Single carriageway multilane roads are not, in general, a very safe type of road, mainly because of the high number of seriously injured victims in head-on collisions, when compared with dual carriageway multilane roads, with a median barrier. 相似文献
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This paper presents the results of a study aimed at validating psychological questionnaires evaluating temperamental and personality features. It discusses their usefulness in diagnosing drivers’ aptitude for safe driving and working as professional drivers. Three psychological questionnaires were validated: the Formal Characteristics of Behaviour – Temperament Inventory (FCB-TI), the Eysenck Personality Questionnaire – Revised and Short Scale (EPQ-R (S)) and the Impulsiveness Questionnaire (IVE). Three groups of drivers (n = 246) aged 19–75 participated in the study. Group I (professional drivers; n = 96) and Group II (nonprofessional drivers; n = 75) had never been involved in road crashes, whereas Group III (nonprofessional drivers; n = 75) were offenders involved in fatal injury road crashes. Criterion-related validity, Cronbach's alpha and Guttman split-half reliability coefficient were in assessing the psychometric properties of the questionnaires. There were some significant differences between Groups II and III for most traits. However, contrary to expectations, higher Emotional Reactivity, Perseveration and lower Endurance as well as higher Neuroticism, Impulsiveness and Venturesomeness were determined for Group II than for Group III. Additionally, the temperament and personality profile of Group II turned out to be less fitted to the profile of safe drivers than that of Group III, whose profile was actually similar to that of Group I. This seems to result from a high tendency for a positive self-presentation among Group I and Group III (a significantly higher result on the Lie scale in comparison with Group II). The results suggest that if psychological tests are to decide on whether a person may be a professional driver or may drive vehicles, the three questionnaires (FCB-TI, EPQ-R(S) and IVE) do not provide a valid diagnosis of professional drivers’ aptitude because of drivers’ high tendency for positive self-presentation. However, they can be used in job counselling and in screening high-risk drivers. 相似文献
58.
Stijn Dhondt Cathy Macharis Nathalie Terryn Fredriek Van Malderen Koen Putman 《Accident; analysis and prevention》2013
Statistics on road traffic accidents (RTAs) mainly come from police records. The police reported RTA statistics however are known to have a large degree of under-registration, underestimating the true risk of being injured in traffic accidents. The use of medical based datasets can provide a more accurate estimate of the actual traffic accident health risk. Exposure-based rates of the actual burden from Flanders and Brussels were calculated, comparing differences between road user, age, gender and type of injury sustained. Minimal Clinical Data (MCD) was selected for the years 2003–2007, as well as data from the mortality statistics. Disability Adjusted Life Years (DALY) were calculated and put into perspective with the passenger kilometres travelled. 相似文献
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《Ergonomics》2012,55(14):1561-1570
Quite correctly, the majority of road safety speeding initiatives focus on drivers travelling at excessive speeds. This study, however, focused on the potential problem of driving too slowly. Six thousand, four hundred and eighty vehicles from around the Perth metropolitan area in Western Australia had their speeds recorded; observations were also made of these vehicles to identify characteristics of the driver and vehicle. In addition, a community survey with 240 members of the public was conducted to examine their attitudes towards slow drivers. As expected, results showed that older drivers drove more slowly than the other age brackets, women drove more slowly than men, and that heavily laden vehicles drove more slowly than other types of vehicles. Additionally, the slowest days were weekdays and the quickest were Saturdays. Community attitudes, generally mirrored the observational findings, and indicated that the public believed that slow driving was sometimes a safety problem causing some accidents. These data are discussed, and some possible countermeasures are briefly introduced to address the problem. 相似文献