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151.
The aim of the present study was to develop and examine the quality of the Ambulance Driver Self-assessment Questionnaire (ADSQ) and the Ambulance Driver Peer-assessment Questionnaire (ADPQ) measuring aspects of, driving performance, driving style and driving competence. In addition the ADSQ measures self-reflection and safety-attitudes. The aim of the study was also to examine ambulance drivers' self- and peer-assessments as well as to examine the accuracy of self-assessments by comparing self-assessed and peer-assessed driving performance, driving style and competence. 76 ambulance drivers employed at two ambulance stations in northern Sweden completed ADSQ and ADPQ. Item analyses were conducted to examine the psychometric properties of the items, and based on the results some revisions were made to improve the questionnaires. The revised questionnaires were functioning rather well, although some subscale demonstrated low internal consistency. Subscale inter-correlations provided support for construct validity. Self- and peer-assessments indicated safe driving performance and good driver competence, which is positive from a traffic safety perspective. A comparison of mean self- and peer-assessment ratings, controlling for age, gender and driving experience showed no significant differences, except for the subscale overtaking. This indicates that ambulance drivers' self-assessments are realistic in most areas.  相似文献   
152.
仿驼足行走机构及其牵引性能   总被引:3,自引:0,他引:3  
分析发骆驼在沙地行走时驼足与沙地相互作用的特点,在此基础上提出了仿驼足行走机构的概念,给出了其结构模型,并用简化实物模型进行了试验验证。试验结果表明,所提出的仿驼足行走机枪机构在沙地上具有较高的牵引性能。  相似文献   
153.
电控燃油喷射用高速电磁阀驱动方式研究   总被引:23,自引:2,他引:23  
对柴油机电控系统脉冲电磁阀的快速响应性进行了分析,从电磁铁结构设计和电路驱动技术两个方面进行了对比,提出并设计了一种基于充电泵的升压驱动电路。实验结果表明,这种驱动电路可以大大缩短电磁阀的响应时间。  相似文献   
154.
When driving in curves, how do drivers use the force appearing on the steering wheel? As it carries information related to lateral acceleration, this force could be necessary for drivers to tune their internal model of vehicle dynamics; alternatively, being opposed to the drivers' efforts, it could just help them stabilize the steering wheel position. To assess these two hypotheses, we designed an experiment on a motion-based driving simulator. The steering characteristics of the vehicle were modified in the course of driving, unknown to drivers. Results obtained with standard drivers showed a surprisingly wide range of adaptation, except for exaggerated modifications of the steering force feedback. A two-level driver model, combining a preview of vehicle dynamics and a neuromuscular steering control, reproduces these experimental results qualitatively and indicates that adaptation occurs at the haptic level rather than in the internal model of vehicle dynamics. This effect is related to other theories on the manual control of dynamics systems, wherein force feedback characteristics are abstracted at the position control level. This research also illustrates the use of driving simulation for the study of driver behavior and future intelligent steering assistance systems.  相似文献   
155.
公路平面交叉口驾驶行为研究   总被引:1,自引:0,他引:1  
面对目前公路平面交叉口交通事故严重的现状,为了公路平面交叉口交通事故致因分析和加深对交叉口驾驶行为的了解程度,探讨了公路平面交叉口驾驶行为理论,总结了目前道路交通系统交通事故原因及其导致事故所占比例,分析了交叉口交通系统,给出了影响交叉口驾驶行为的具体因素。在驾驶行为三阶段基础上,研究了交叉口驾驶行为模型,分析了交叉口驾驶行为特征和交叉口驾驶行为与交通事故发生的一般关系。并针对驾驶失误和不安全驾驶行为给出了防止措施,以减少交叉口交通事故。  相似文献   
156.
以LTY8型摊铺机为例,介绍了一种典型的摊铺机后桥双轮驱动方式,并分析了其良好的附着性能及避免产生寄生功率的问题。  相似文献   
157.
轮胎印迹内垂直载荷的分布与形式的选择,对建立轮胎制动与驱动特性的理论模型有很大影响。根据轮胎制动和驱动时印迹内垂直载荷分布特性,以及轮胎的前后变形特性,建立了轮胎制动、驱动特性的理论模型。应用该理论模型的计算结果,与试验结果具有很好的一致性。  相似文献   
158.
引入了图的符号树控制的概念,给出一个连通图G的符号树控制数γr(G)的一个上界和一个下界,说明了这两个界限均是最好可能的,并确定几类特殊图的符号树控制数,这包括了圈、轮图、完全图和完全二部图.  相似文献   
159.
Potential benefits of an adaptive forward collision warning system   总被引:1,自引:0,他引:1  
Forward collision warning (FCW) systems can reduce rear-end vehicle collisions. However, if the presentation of warnings is perceived as mistimed, trust in the system is diminished and drivers become less likely to respond appropriately. In this driving simulator investigation, 45 drivers experienced two FCW systems: a non-adaptive and an adaptive FCW that adjusted the timing of its alarms according to each individual driver’s reaction time. Whilst all drivers benefited in terms of improved safety from both FCW systems, non-aggressive drivers (low sensation seeking, long followers) did not display a preference to the adaptive FCW over its non-adaptive equivalent. Furthermore, there was little evidence to suggest that the non-aggressive drivers’ performance differed with either system. Benefits of the adaptive system were demonstrated for aggressive drivers (high sensation seeking, short followers). Even though both systems reduced their likelihood of a crash to a similar extent, the aggressive drivers rated each FCW more poorly than their non-aggressive contemporaries. However, this group, with their greater risk of involvement in rear-end collisions, reported a preference for the adaptive system as they found it less irritating and stress-inducing. Achieving greater acceptance and hence likely use of a real system is fundamental to good quality FCW design.  相似文献   
160.
车辆行驶工况与特征的研究   总被引:5,自引:0,他引:5  
先对几个典型国家和地区(美国、欧洲和日本)开发并采用的几种有代表性的行驶工况做了全面的介绍;接着,对它们各自的特征进行深入的研究和对比;最后得出几点结论。  相似文献   
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