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541.
This paper presents a new controller design method based on a data-mining polynomial algorithm. We show application of a polynomial
data-mining algorithm, where an input-state linearized polynomial vehicle model is developed for very low speed operation
and, without introducing any processes with fudge factors, control inputs of a nonlinear system are obtained in the original
coordinates. We verify the developed modeling method and controller design method through numerical experiments. 相似文献
542.
543.
In Europe, ports are confronted with a closer integration in the maritime and shipping industries. The co-operation agreements can take several forms such as alliances and mergers among shipping lines, conferences, involvement of shipping companies in terminal management, and extending interests in inland transport of shipping companies. In this paper we give a brief overview of these different types of agreement and we examine the consequences of this evolution of the market structures in which ports and shipping companies have to operate. More specifically, attention goes to the competitive position of the port in this new environment. It is clear that the role of the port and the port authorities has to be redefined to guarantee that it remains a fully fledged player in this fast evolving integrated market. 相似文献
544.
This paper presents a space vector current controller for a brushless permanent magnet motor in electric and hybrid electric
vehicles. The proposed current controller selects space vectors based on the sector selection under a three-level hysteresis
comparator to decrease the current ripple. The proposed approach can improve the performance of a brushless PM drive such
as the average switching frequency and the total harmonic distortion (THD) compared with the conventional hysteresis current
control. The experiment is performed first to verify the proposed control. Then, the method is implemented in a hybrid electric
vehicle simulation model with standard driving cycles based on the control strategy to evaluate the drive performance in the
vehicle system. The experimental and simulation results indicate that the presented control can improve the performance of
the brushless PM machine drive. 相似文献
545.
Y. Shi I.- T. Lee A. Md. Afsar J.- I. Song 《International Journal of Automotive Technology》2009,10(4):481-488
As the number of disabled people grows, independence and mobility become a priority for those individuals. To achieve this
goal, a ‘Turny-type power seat’ was developed in this study to assist a disabled person rise from a vehicle without trouble.
The design and modeling of the power seat were performed using AutoCAD and CATIA software. The major motions of the power
seat system are swiveling, sliding, and extending, which are accomplished primarily by DC motors, chains, and gears. Most
of the power seat parts were made from mild steel. Welding technology was used throughout the frame fabrication. To ensure
the safety and stability of the power seat, various tests were performed, and the results analyzed. The static analysis of
the power seat was carried out by ANSYS 11.0. The results showed that the power seat conformed to the Americans with Disabilities
Act (ADA) standards. The durability test was performed by repeatedly rotating and sliding the power seat under loading conditions.
Dynamic crash simulation was carried out using the LS-DYNA software. The durability test ensured a longer life of the power
seat, while the crash analysis showed a small rotational distortion that was not harmful to passengers. However, the front
seat had a slightly larger forward displacement, which was not comfortable for passengers. Therefore, further modifications
of the power seat should be done to improve the performance, with attention given to the reduction of the forward displacement
in the event of a crash. 相似文献
546.
K. -H. Moon S. -H. Lee S. Chang J. -K. Mok T. -W. Park 《International Journal of Automotive Technology》2009,10(4):441-449
Many methods we have been developed to control the rear wheels of a vehicle, but most of them are designed for automobiles
with four wheels. The AWS (all wheel steering) control method for articulated vehicles is currently applied only to Phileas
vehicles developed by APTS, but the control algorithm for this system has yet to be reported. In the present paper, a new
algorithm is proposed after the AWS ECU (electronic control unit) of the Phileas vehicle was tested and analyzed in order
to understand the existing steering algorithm. The new algorithm considers the vehicle geometry, stability of handling, and
safety, and can be easily applied to multi-axle vehicles. In order to verify the AWS algorithm, the trajectory and steering
angles of each algorithm were compared using the commercial software ADAMS. Turning radius, swing-out, and swept path width
were also investigated to determine the turning performance of the proposed algorithm. 相似文献
547.
C. -L. Wang C. -L. Yin T. Zhang L. Zhu 《International Journal of Automotive Technology》2009,10(5):589-596
The powertrain of an ultra-capacitor-based parallel hybrid electric vehicle (HEV) was developed. Innovations, such as the
engine management system, floating ISG (Integrated Starter and Generator), electronic-controlled double-clutch system and
dual-driven air conditioning system were realized. Hybrid control strategies to improve the fuel economy and reduce emissions
were analyzed briefly. In order to ensure the vehicle emission performance, the engine management system calibration was performed.
The vehicle emission test was also conducted, showing that the vehicle emission satisfied the EURO III standard and has great
potential for improvement. The hybrid start test was introduced in detail. We realized the hybrid function and start parameter
optimization of the engine and ISG. 相似文献
548.
大跨悬索桥箱形钢桁架梁的综合疲劳评定方法研究 总被引:1,自引:1,他引:0
根据大跨桥梁铜箱梁各类构件的受力特点建立了确定钢箱梁关键疲劳构件的评价模型,提出了基于结构有限元分析、应变监测信息、构件分级系统和桥梁结构人工检测等多方面信息综合评定关键疲劳构件的方法。以某大跨悬索桥钢箱梁结构为例,结合结构有限元数值计算和结构健康监测系统确定的关键钢箱梁截面,针对关键截面上的主要构件分布,利用应变传感器输出信息、结构有限元分析得到的应力分布信息、人工检测信息和桥梁主要构件的危险等级和易损等级信息,结合层次分析法和模糊综合评判理论确定了影响钢桥构件疲劳评定的各因素的权重,用综合隶属度评分法进行关键疲劳构件的等级评定。 相似文献
549.
The vibrational characteristics of automotives during idling were studied experimentally by considering the axial forces of
the drive shaft and the spider positions in a constant-velocity joint. The generated forces, such as PF (plunging force) and
GAF (generated axial force) in the assembly of the drive-shaft module, were measured directly by an experimental apparatus.
Measurements of the GAF and PF did not show the same trends as the joint angles. They depended instead on the types of CV
joints. In addition, the relationship between the offset values of the shaft and the spider positions in the tulip of the
constant-velocity joint were studied. As a result, the idle vibration characteristics were affected by the variation of the
spider positions and the vibrational characteristics in the axial direction of the shaft, including the amplitude and the
harmonic periods. 相似文献
550.
Piet M. T. Broersen 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1974,3(2):109-121
The so-called critical speed of a linearized railway vehicle is shown to be no useful measure for the stability of the system in practice. The important interaction between vehicle and track can be taken into account by the riding quality for a certain vehicle on every particular piece of track. The riding quality is determined by the accelerations transmitted to the payload, weighted according to comfort standards, and the relative displacements between wheel and rail. From the riding quality demands both for vehicle design and for maintenance of the track can be derived. 相似文献