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A closed form solution to the problem of segmenting multiple 3D motion models was proposed fromstraight-line optical flow. It introduced the multibody line optical flow constraint (MLOFC), a polynomial equation relating motion models and line parameters. The motion models can be obtained analytically as the derivative of the MLOFC at the corresponding line measurement, without knowing the motion model associated with that line. Experiments on real and synthetic sequences were also presented. 相似文献
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ABSTRACTBased on the increasing demands of transportation development, the concept of an Intelligent Transportation System (ITS) has received increasing attention in both academic and industry arenas. It integrates information, communications, computers and other technologies, and applies them in the field of transportation to build an integrated system of people, roads and vehicles by utilizing advanced data communication technologies. It can establish a large, fully functioning, real-time, accurate and efficient transportation management system. Intelligent transportation systems shift the focus from road managers to road users. In order to achieve this purpose, intelligent transportation systems use advanced technology to provide drivers with convenient information to help reduce traffic congestion and to increase available road capacity. This special issue is dedicated to exploring the most recent advances in intelligent transportation systems and big data based on intelligent technology. 相似文献
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在动态工况下,PEM燃料电池单电压的稳定性是燃料电池动力系统持续稳定运行的保障,而质子交换膜的水合状态、阴极和阳极的排水状态、氢氧燃料传质效应都会显著影响单电压的稳定性。本文基于PEM燃料电池组动态工况试验,引入相对平均电压、相对差异度等指标以分析各燃料电池组单电压的稳定性,探究燃料电池组各电堆单元单电压随工况的变化规律及影响因素,以评价燃料电池电堆性能,指导系统控制策略的制定。 相似文献
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Dongmei Wu Haitao Ding Changqing Du 《International Journal of Automotive Technology》2018,19(1):135-146
Compared with internal combustion engine (ICE) vehicles, four-wheel-independently-drive electric vehicles (FWID EV) have significant advantages, such as more controlled degree of freedom (DOF), higher energy efficiency and faster torque response of an electric motor. The influence of these advantages and other characteristics on vehicle dynamics control need to be evaluated in detail. This paper firstly analyzed the dynamics characteristics of FWID EV, including the feasible region of vehicle global force, the improvement of powertrain energy efficiency and the time-delays of electric motor torque in the direct yaw moment feedback control system. In this way, the influence of electric motor output power limit, road friction coefficient and the wheel torque response on the stability control, as well as the impact of motor idle loss on the torque distribution method were illustrated clearly. Then a vehicle dynamics control method based on the vehicle stability state was proposed. In normal driving condition, the powertrain energy efficiency can be improved by torque distribution between front and rear wheels. In extreme driving condition, the electric motors combined with the electro-hydraulic braking system were employed as actuators for direct yaw moment control. Simulation results show that dynamics control which take full advantages of the more controlled freedom and the motor torque response characteristics improve the vehicle stability better than the control based on the hydraulic braking system of conventional vehicle. Furthermore, some road tests in a real vehicle were conducted to evaluate the performance of proposed control method. 相似文献
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随着人口增长和城市化进程的加快,引发并刺激了对住宅的巨大需求。而我国采用高投入、高消耗、高污染的传统砖石住宅结构体系,已难以满足市场、消费者的要求和建筑"可持续发展"的时代主题。冷弯薄壁住宅钢结构发展潜力巨大,作为传统住宅结构体系的理想替代品,其具有更加明显的综合经济效益。 相似文献
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以上海轨道交通8号线南延伸段(贯穿世博园区)移动通信引入工程为例,重点介绍了3G网络在轨道交通中信号覆盖方案及系统组成,并概述了信号覆盖方案及链路预算,可为同类工程设计提供参考。 相似文献