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981.
982.
An experiment was conducted to find the variability of driver eye movement according to different driving experience.An eye tracking system was used to study the regularity of driver eye movements, such as fixation duration, variations of fixation points, and the distribution of glance zone.It was found that driving experience had a significant effect on driver eye movement behavior.The percentage of fixation duration to total glance time for inexperienced drivers was 61.5%, while the percentage for experienced drivers was 50.2%.Moreover, the majority of drivers paid attention to the left region of the field of view more frequently than the central and the right regions.This study indicates that it takes inexperienced drivers more time to recognize traffic signs.The findings from this study will assist traffic engineers in designing and installing the traffic signs in an optimal way. 相似文献
983.
Access to any development is a connection between the buildings and urban roadways. The impact of access on urban roads varies with location of the access. This paper studies the impact of access to large buildings on the surrounding road network by exploring traffic conflicts based on the configuration of the access. The concept of conflict intensity is introduced in this study as a new evaluation indicator to evaluate the traffic conflict triggered by the presence of access. The results show that the greater the speed, the greater the conflict intensity of access. Meanwhile, a similar situation exists when other variables (e.g., conflict angle or the number of conflicts) change. The larger the conflict intensity, the more dangerous the access. Results from this study can help developers and traffic engineers choose suitable locations of access and organize the traffic in a logical manner. 相似文献
984.
在我国,交通工具种类众多,影响城市客运方式选择的因素纷繁复杂. 为了简化分析过程,筛选客运方式选择主要的影响因素是研究交通方式选择的基础. 对苏州等4个代表性城市居民出行调查数据进行因子分析. 采用SPSS中因子分析的主成份分析法,筛选出影响城市5种典型客运方式选择的主要个体属性影响因素,结合社会环境影响因素,得出影响每种客运方式选择的因素. 在分析过程中,也识别了因素间的主次、关联关系,为进一步量化与分析决策提供依据. 选取的数据直观简洁,能实际有效地反映居民对客运方式的选择,为城市交通管理部门制定合理的交通组织方案奠定基础. 相似文献
985.
计算机技术、网络技术、多媒体技术正在飞速发展而且应用日益广泛,把多媒体CAI课件作为一种辅助教学手段引进体育教学课堂,是21世纪高校体育改革的必然趋势;本文通过游泳教学实践,探讨了多媒体技术在水上专业游泳教学中的应用,实验表明:有显著性的差异,教学效果优于传统教学. 相似文献
986.
Rong-Guo Fu Li Wang Jian-Ping Zhou Feng Ma Xiao-Dan Liu Heng Ge Jun Zhang 《西安交通大学学报(英文版)》2010,22(3):203-207
Objective To investigate the effect of Levocarnitine on lipid metabolism and nutritional status of maintenance hemodialysis (MHD) patients and possible mechanism. Methods A total of 40 MHD patients [mean age (53.5±7.1) years] who underwent normal hemodialysis more than 6 months were randomly classified into two groups, Levocarnitine supplemented group (LS-G) (n=20; Levocarnitine supplementation after each normal hemodialysis session, at a dose of 1.0 g/day by intravenous administration) and control group (C-G) (n=20; normal hemodialysis). Before treatment, one month and three months after treatment we respectively measured or observed the following items, the tolerance to hemodialysis, carnitine level in plasma, C-reactive protein, IL-6, TNF-α, percentage of neutrophil, and some relevant nutritional parameters, such as lipid profile, transferrin, total protein, albumin and prealbumin levels. Comparative analysis was conducted between the two groups. Results In LS-G three months after treatment, the levels of carnitine, hemoglobin, and prealbumin in plasma were significantly increased (P<0.05), but C-reactive protein, neutrophil percentage, low-density lipoprotein and triglyceride were significantly decreased (P<0.05) in contrast to those in C-G and before treatment. Transferrin, total protein, and albumin were elevated in LS-G, with no statistical significance. Conclusion There was a significant improvement of lipid metabolism and nutritional status for the long-term maintenance hemodialysis patients with Levocarnitine supplementation. And this improvement is related to the decrease of inflammatory factors. 相似文献
987.
随着我国高等职业教育发展,以任务驱动、就业导向的教学理念深入人心,培养能够从事专业岗位的高等技术应用性人才的教育目标也得到高职院校的广泛认同。T-TEP是丰田技术培训计划的简称,是丰田公司针对客户要求和提高自身售后服务水平需要而开发的针对员工培训的课程和证书考核体系。文章在总结T-TEP特点的基础上,分析其对职业院校专业课程体系改革的启示。 相似文献
988.
客运车站安全智能视频监控系统研究 总被引:1,自引:0,他引:1
本文首先介绍铁路客运车站安全视频监控系统的发展情况,分析系统的应用需求,应用智能视频分析技术设计了客运车站安全智能视频监控系统框架和实现关键技术. 相似文献
989.
设计实现了一种基于PCI总线的智能双通道RS422通信卡.板卡的核心部分包括PCI总线控制器PLX9052、双口RAM,CPLD,AVR单片机Atmega128,异步收发器,及RS422总线接口芯片.介绍RS422通信卡的硬件实现及系统软件结构,包括应用程序设计和WDM驱动程序设计.该通信卡允许多达128个的接口芯片接在同一总线上,便于实现多机通信.该接口卞可以用于高速的数据通信中,并且在计算机联锁全电子智能化执行机中得到了很好的应用. 相似文献
990.
该文介绍了一个DN1000顶管穿越DN1200煤气管道及2-2400×2400污水箱涵的工程实例。其中,顶管与污水箱涵净间距仅为1.5m。为保护既有管线,加强了对既有管线、箱涵及地层沉降的监测。根据监测结果,合理调整了顶管施工各项参数。监测数据表明,该工程的地层损失率最大为3.4%,管线处地层损失率最大为1.5%,最终,把煤气管线和污水箱涵的变形控制在容许范围内。 相似文献