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101.
设计并实现了一种基于DM642视频车辆检测系统。提出了一种基于虚拟线圈匹配的算法,算法原理是估计车辆的速度和结合背景差统计量来检测通过监测区域的车辆,把算法移植到DM642平台中进行处理运行,处理结果可以满足视频处理的实时性要求,并且算法对外界环境变化的干扰有一定的鲁棒性,准确的车流量检测精度,并且运行稳定。 相似文献
102.
Abstract The aims of this study were: (1) to characterize selected fitness and health attributes of two types of habitual recreational off-road vehicle riders – off-road motorcyclists and all-terrain vehicle riders; (2) to explore differences among riders in terms of vehicle type, age, and gender; and (3) to compare the fitness and health of riders to population norms and clinical health standards. Canadian off-road riders (n = 141) of both sexes aged 16 years and over were recruited through local and national off-road riding organizations. Anthropometry, fitness, and health measures of off-road motorcycle and all-terrain vehicle riders were compared with population norms, health standards, and physical activity guidelines. Off-road motorcycle riders had above average aerobic fitness (79th percentile), while all-terrain vehicle riders were lower than average (40th percentile). All riders had a healthy blood lipid profile and a low incidence of the metabolic syndrome (12.9%) compared with members of the general population. Off-road motorcycle riders had healthier body composition and fitness than all-terrain vehicle riders; however, the body composition of off-road motorcycle riders was no healthier than that of the general population and all-terrain vehicle riders were worse than the general population. Off-road motorcycle riders had healthier anthropometry and fitness than all-terrain vehicle riders and thus fewer health risk factors for future disease, demonstrating that the physiological profiles of off-road riders are dependent on vehicle type. 相似文献
103.
创新能力的培养对于学生的发展有着举足轻重的作用,也是衡量人才的重要标准。很多地方性高校在创新能力培养方面做了很多工作,取得了很好的效果。本文主要从车辆工程专业学生的专业特点出发,分析本科生创新能力培养途径,从教学方法、实践教学、创新创业项目和营造校园创新氛等多个方面,促进学生创新能力的提升。 相似文献
104.
Thisworkaimsatcreatingamathematicalmodelabletodescribethemotionofpurerollingofaroad vehicle ,whentheelectricalenginesactdirectlyonthewheels.Furthermore ,itshouldbeabletodeterminetheforcesgeneratedbythecon tactofthewheelswiththeground . Themechanicalmode… 相似文献
105.
A statistical approach to evaluate the subjective perception of the annoyance caused by the vehicle noise was presented in this paper. After recording the noises of Sanfeng, Huali and Xiali at speeds of 30, 40, 50, 60, 70 and 80 km/h respectively, the annoyance of the vehicle noises was evaluated in the testing room using paired comparison method, and the sound quality metrics and subjective annoyance were then distilled. Loudness, sharpness, roughness, periodicity and impulsiveness were selected for each of the vehicle noises. By correlation analysis method, it can be found that loudness has a higher correlation (0.91) with annoyance than other parameters. Meanwhile, sharpness, periodicity, roughness and impulsiveness have correlation with subjective perception with correlation coefficients being 0.84,-0.82, 0.62 and 0.87, respectively. The result of multiple regression analysis shows that calculated annoyance obtained by the regression equation can explain the perceptual annoyance and the regressed evaluation model is feasible to evaluate the sound quality of vehicle. 相似文献
106.
车用发动机连杆有限元分析 总被引:4,自引:0,他引:4
应用有限元方法,以一台车用柴油机的连杆为例,对该机连杆的强度进行了分析。研究了静态计算时边界条件的合理处理方法,应用多体动力学软件分析了连杆上作用载荷的施加方法,并通过模态分析技术分析了连杆的部分动态特性。本研究为今后连杆的改进设计提供了准确的理论依据。 相似文献
107.
汽车传感器和车载网络技术是汽车类专业的一门拓展应用能力的课程,包含了传感器和网络技术两方面的知识,具有知识量大、理论性强、课程各单元关联性差等特点。为了适应应用型汽车专业发展的需要,以提高学生学习兴趣、降低课程难度为目标,从教学内容、教学方法、课程资源建设和课程考试方案等方面对课程的改革措施进行探讨,改变以往重理论、重基础、轻实践和应用的教学模式。 相似文献
108.
针对标准遗传算法在解决带时间窗的车辆路径问题(VRPTW)时存在早熟收敛和易陷入局部极值点的特点,引入遗传算法与禁忌搜索结合的混合算法,同时对杂交算子进行了改进.算法既具有遗传算法的全局性和并行性,又具有禁忌搜索算法的爬山能力.实验表明,改进的混合算法具有计算效率高、收敛速度快等特点,是一种有效的方法. 相似文献
109.
基于GPS的无人车导航控制系统由无人车导航终端和监控站两部分组成。采用GPS技术实现无人车的实时定位和跟踪;利用串口通信编程与百度地图的二次开发实现监控站软件设计,通过无线传输实现无人车与监控站的信息交互,最终控制无人车按规定路线行驶。 相似文献
110.