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自动售检票系统检测中心检测理念与实施策略 总被引:1,自引:0,他引:1
蔡佳妮 《城市轨道交通研究》2011,14(1):24-28
在上海轨道交通自动售检票(AFC)系统检测中心建设已初具规模的背景下,通过对AFC系统检测方法的研究,结合检测过程中的具体经验,从独立于系统集成商、设备厂家的测试方的角度,探讨了检测中心的检测理念,明确了检测需求类别、检测依据和检测方法.重点介绍了检测中心的检测实施策略,提出了检测实施中各个环节的过程管理流程,以使检测... 相似文献
965.
为了深化普通高校体育教学改革,探讨面向21世纪普通高校体育与健康课的改革与发展,在普通高校体育与健康课中落实素质教育。本文通过采用文献资料法、调查法、实验对照法,数理统计法,对普通高校广州航海高等专科学校、广东农工商职业技术学院、平顶山学院体育与健康课中存在的问题进行调查、分析。并在体育与健康课中运用“套餐”和“自助餐”的教学形式,取得了令人瞩目的效果,同时也为新一轮基础教育课程改革提供教学依据。 相似文献
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Riccardo Amirante Carlo Coratella Elia Distaso Gianluca Rossini Paolo Tamburrano 《International Journal of Automotive Technology》2017,18(4):729-742
Since the needle displacement exerts a fundamental influence on the operation of Common Rail injection systems, accurate measurements of the control piston position can be crucial for a more thorough analysis of the behaviour of injectors, in particular when multiple injections are employed. Eddy current sensors have traditionally been used in lab activities to measure the control piston position inside injectors; apart from the high cost, the scientific literature clearly shows their inadequacy, which is mainly due to the presence of electromagnetic disturbance: the current pulse, which controls the opening of the injector, generates electromagnetic fields which strongly affect the acquisition of data. Many attempts have recently been made either to solve the interference occurring during such measurements or to propose alternative displacement transducers whose operation is not influenced by electromagnetic interference. In this paper, a new device for measuring the injector opening is proposed: it is an optical transducer characterized both by simple and very cheap construction and by a reliable physical principle for measuring the control piston lift. The reliability of the proposed sensor is assessed by a thorough experimental campaign and by comparing the experimental results with the numerical predictions achieved by a Common Rail injector model. Since the assembly of the optical sensor does not affect the injector operation, it can efficiently be used both for experimental tests and for on-board diagnosis and monitoring of the injector operation. 相似文献
968.
Myung-Seop Lim Dong-Min Kim Jung-Pyo Hong 《International Journal of Automotive Technology》2017,18(3):499-504
This paper deals with the speed response characteristic of the concentrated flux synchronous motor (CFSM) using ferrite magnets for the electric power steering (EPS) system. To analyze the response characteristic of the CFSM, an analytical method using the electromechanical undamped natural frequency and damping ratio based on the transfer function is proposed. By using the method, the speed response according to the variations of the shape of the permanent magnets (PMs) and rotor core is analyzed. It was analyzed under the conditions of the constant volume of the PMs as well as the constant diameter of the rotor. By using the proposed analysis method, the improved model is desgined based on the initial model fulfilling the required specifications. Finally, the torque and speed response characteristics of two motors are simulated through the finite element analysis (FEA) and MATLAB Simulink. 相似文献
969.
Junho Cho Tae-Kyung Kim Kyu-Hong Kim Kwanjung Yee 《International Journal of Automotive Technology》2017,18(6):959-971
To reduce the aerodynamic drag, the performance of the underbody aerodynamic drag reduction devices was evaluated based on the actual shape of a sedan-type vehicle. An undercover, under-fin, and side air dam were used as the underbody aerodynamic drag reduction devices. In addition, the effects of the interactions based on the combination of the aerodynamic drag reduction devices were investigated. A commercial sedan-type vehicle was selected as a reference model and its shape was modeled in detail. Aerodynamic drag was analyzed by computational fluid dynamics at a general driving speed on highway of 120 km/h. The undercover reduced the slipstream area through the attenuation of the longitudinal vortex pair by enhancing the up-wash of underflow, thereby reducing the aerodynamic drag by 8.4 %. The under-fin and side air dam showed no reduction in aerodynamic drag when they were solely attached to the actual complex shape of the underbody. Simple aggregation of the effects of aerodynamic drag reduction by the individual device did not provide the accurate performance of the combined aerodynamic drag reduction devices. An additional aerodynamic drag reduction of 2.1 % on average was obtained compared to the expected drag reduction, which was due to the synergy effect of the combination. 相似文献
970.
Yunlong Qi Changle Xiang Weida Wang Boxuan Wen Feng Ding 《International Journal of Automotive Technology》2018,19(2):345-358
Power-split hybrid electric vehicles (HEVs) have great potential fuel efficiency and have attracted extensive research attention with regard to their control system. The coordinated controller in HEV plays an important role in tracking the optimal state reference generated by the energy management strategy (EMS), so as to reach the desired fuel efficiency. Meanwhile, the coordinated controller also has a significant impact on driving performance. To improve its performance, the design of a model predictive control (MPC) based coordinated controller in power-split HEV is presented. First, a non-linear, time-varying constrained control oriented transmission model of a dual-mode power-split HEV is formulated to describe this control problem. Then, to solve this problem, the non-linear part in the transmission model is linearised, and a linear MPC is used to obtain the control signals for the motors and engine at each time step. To meet the requirements of real-time computation, a fast MPC method is also applied to reduce the online computation effort. Simulations and experiments demonstrate the effectiveness of the proposed MPC-based coordinated controller. 相似文献