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51.
Aiming at the problem that the fast tracking algorithm using spatio-temporal context (STC) will inevitably lead to drift and even lose the target in long-term tracking, a new algorithm based on spatio-temporal context that integrates long-term tracking with detecting is proposed in this paper. We track the target by the fast tracking algorithm, and the cascaded search strategy is introduced to the detecting part to relocate the target if the fast tracking fails. To a large extent, the proposed algorithm effectively improves the accuracy and stability of long-term tracking. Extensive experimental results on benchmark datasets show that the proposed algorithm can accurately track and relocate the target though the target is partially or completely occluded or reappears after being out of the scene. 相似文献
52.
客观、准确地评价旧沥青的老化程度是沥青路面再生技术的基础,而正确回收旧沥青是基础中的基础,影响到再生技术方案的决策、新材料的选择、再生混合料设计等。现行阿布森法回收沥青的试验规程(T0726-2011)是根据普通沥青而制定的,并不适用于SBS改性沥青。该文以阿布森回收方法为试验基础,通过分子扩散理论与表面张力机理分析,确定试验控制的关键参数。通过空白改性沥青标定试验对关键控制参数进行优化与验证。结果表明:SBS改性沥青可以采用阿布森法回收,回收的SBS改性沥青的三大指标、黏度、弹性恢复与空白沥青基本一致。提出了改性沥青回收的关键步骤,规范了改性沥青回收的溶液浓度、蒸馏温度、CO2通气量以及延迟加热时间等关键控制参数。 相似文献
53.
填方土体湿化变形数值模拟 总被引:1,自引:0,他引:1
介绍了湿化变形计算模式,将无拉应力模型应用到湿化变形计算.应用该模型,利用有限元对算例进行了不同湿化参数下湿化引起的位移计算,并对结果进行了分析,提出了一些建议,为工程设计提供参考. 相似文献
54.
To improve the accessibility of transit system in urban areas, this paper presents a flexible feeder transit routing model that can serve irregular‐shaped networks. By integrating the cost efficiency of fixed‐route transit system and the flexibility of demand responsive transit system, the proposed model is capable of letting operating feeder busses temporarily deviate from their current route so as to serve the reported demand locations. With an objective of minimizing total bus travel time, a new operational mode is then proposed to allow busses to serve passengers on both street sides. In addition, when multiple feeder busses are operating in the target service area, the proposed model can provide an optimal plan to locate the nearest one to response to the demands. A three‐stage solution algorithm is also developed to yield meta‐optimal solutions to the problem in a reasonable amount of time by transforming the problem into a traveling salesman problem. Numerical studies have demonstrated the effectiveness of the proposed model as well as the heuristic solution approach. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
55.
在车辆快速增加的同时,交通事故也随之增加。本文从交通肇事者的法定义务问题着手,从行为人刑事不作为的角度出发。分析交通肇事逃逸行为的故意犯罪性质,对逃逸问题在立法的深层价值取向上剖析立法本意,并对司法解释中有关指使他人“逃逸”构成犯罪的问题尝试作出解读。 相似文献
56.
57.
机车车辆有关配件制造的新材料、新技术、新工艺(二) 总被引:1,自引:0,他引:1
邹稳根 《铁道机车车辆工人》2007,(12):26-30
8制动盘的新材料、新工艺8.1铝-碳化硅复合材料制动盘铝合金制动盘一方面由于磨损严重,另一方面有抱闸可能,所以其摩擦性能难以令人满意。采用碳化硅粒子增强的铝基复合材料(CMA)制动盘 相似文献
58.
Shuqi Song Peng Han Dong Zou 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(1):113-127
The rail is modelled as a simply supported beam in the vehicle–track coupled dynamics. The beam is formulated by a partial differential equation that is transformed into an ordinary differential equation by the method of mode superposition for numerical calculation. However, the size of the matrix that is formed by the mode-superposition method increases significantly with track length, which limits the calculation efficiency. Some methods have been developed to solve this calculation issue, but they diminish the merits of the vehicle–track coupled dynamics, which would systematically investigate the dynamics of a vehicle and a track from the entire vehicle–track system. A new method is developed to resolve this contradiction. First, a theory based on a sliding window is established to improve the computational stability with respect to the length and the window-movement ratio. Then, two methods, namely finite element method analysis and an analytical solution, are used to verify the accuracy of the new method, which is highly efficient when used in a vertical half-vehicle–track coupled model to calculate the vehicle response when the vehicle moves on a long track. The results of the vehicle response calculated with and without the sliding window show good consistency. 相似文献
59.
通过对泰国摩托车认证制度的分析和研究认为,泰国摩托车认证程序和方法与世界其他各国相比并没有特别严厉的要求,技术认证方面无太大的障碍,只要应对充分,我国摩托车完全有能力进入泰国,有巨大的发展空间和机遇。 相似文献
60.
青藏铁路清水河段加筋路堤的试验研究 总被引:2,自引:2,他引:0
通过对青藏铁路清水河段加筋路堤一些初步的试验研究 ,分析加筋路堤在保护多年冻土和维护铁路路基稳定性方面的作用 ,对该加筋路堤下地温情况及多年冻土的人为上限进行分析研究。 相似文献