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561.
根据我国新建高速客运专线和200 km·h-1既有线提速改造的实际情况,以有砟轨道结构为研究对象,进行轨道结构动态响应有限元建模与轨道不平顺影响的动力分析、落轴冲击数值计算和不同垫层隔振性能分析、无缝线路钢轨振动特性谐波响应分析及室内实尺模型试验,研究轨道结构动态特性. 相似文献
562.
船舶避碰智能决策支持系统的设计与实现 总被引:10,自引:3,他引:7
建立了基于多库模式的船舶避碰智能决策支持系统(IDSSVCA),描述了系统的总体结构,并对各个库进行简要的介绍,讨论了多库协同器的组成和作用,同时给出了系统的工作流程图,最后通过实例说明系统运行的可行性和有效性。 相似文献
563.
Victor Y. B. Yung David J. Cole 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2006,44(1):1-31
Little information on automotive damper performance above 30 Hz is found in the published literature. Design of vehicles for low levels of noise, vibration and harshness requires attention to higher frequencies. This paper describes research into modelling damper behaviour at frequencies up to 500 Hz. The performance of a monotube damper was measured and the empirical data were used to evaluate a recently published parametric model. Methods of assessing prediction accuracy using transfer and coherence functions, and a wavelet-based transfer function were introduced. Modifications to the model were then developed to improve the prediction of high-frequency behaviour. 相似文献
564.
建立保持共产党员先进性教育活动的长效机制,有效地提高共产党员的光荣感、使命感和责任感,永葆共产党员的政治本色,应该倡导共产党员佩戴党徽。本文详细介绍了佩带党徽的重要意义和作用。 相似文献
565.
Milad Jalali Ehsan Hashemi Amir Khajepour Shih-ken Chen Bakhtiar Litkouhi 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(2):319-340
In this paper, a model predictive vehicle stability controller is designed based on a combined-slip LuGre tyre model. Variations in the lateral tyre forces due to changes in tyre slip ratios are considered in the prediction model of the controller. It is observed that the proposed combined-slip controller takes advantage of the more accurate tyre model and can adjust tyre slip ratios based on lateral forces of the front axle. This results in an interesting closed-loop response that challenges the notion of braking only the wheels on one side of the vehicle in differential braking. The performance of the proposed controller is evaluated in software simulations and is compared to a similar pure-slip controller. Furthermore, experimental tests are conducted on a rear-wheel drive electric Chevrolet Equinox equipped with differential brakes to evaluate the closed-loop response of the model predictive control controller. 相似文献
566.
提出了一种在静止背景交通图像序列中运动车辆的检测和分类方法,即基于GVF-Snake模型和惯量椭圆的车辆分类算法。利用混和高斯模型(GMM)、期望最大化(EM)估计算法、改进GVF-Snake模型,从序列交通视频图像中检测出运动车辆;然后,借用刚体惯量椭圆原理,计算运动车辆等效椭圆偏心率,从而建立车长-车投影面积-车的等效椭圆偏心率三参数建立了车辆分类器。该方法的车辆检测与分类都是基于数理统计原理,算法复杂度小,可用数字逻辑编程实现,适合在嵌入式系统中应用。 相似文献
567.
V形支撑结构施工阶段的空间应力分析 总被引:1,自引:0,他引:1
采用空间有限元程序ANSYS,对某V形支撑连续梁的V形支撑结构进行施工阶段的空间应力分析,研究V形支撑结构在施工阶段时的应力分布及变化情况,为类似结构的设计提供一定的参考. 相似文献
568.
569.
在交通量预测中,社会经济指标(主要指国民生产总值)是最基础的预测数据。结合具体实例,研究灰色预测模型在社会经济指标中的应用方法,证明其应用效果良好。 相似文献
570.
Wireless ICTs are often used in public transport. Using survey data collected amongst 98 train travellers this article aims
to gain insight into important factors that affect train travellers’ intentions to communicate with distant others while travelling.
More specifically, the focus is on the decision-making process that leads to the intention to choose for a confidential conversation
either via ‘audible’ mobile phone or via ‘silent’ SMS/e-mail. An approach that is related to the Extended Model of Goal-directed
Behaviour (EMGB) is applied. Structural equation modelling results indicate that in particular past SMS behaviour, the desire
to communicate (goal desire), the perceived efficacy and controllability influence the intention to conduct a confidential
phone conversation in the train. The influence of the social environment (e.g. eavesdropping) seems to be less important.
Several EMGB constructs are strongly influenced by age. It seems that older respondents have more negative attitudes towards
telephoning while travelling by train, and find it more difficult to call other people in such a situation. Finally, they
have a lower intention than younger respondents to conduct a confidential conversation over the phone while travelling.
相似文献
Martin DijstEmail: |