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991.
人行横道因其建设维护费用低、行人过街便捷等特点,被广泛地应用于行人过街的交通组织之中。在不同控制方式下的人行横道上,行人过街存在不同的问题。以北京市展览馆路段为例,针对有无信号灯控制路段人行横道的交通状况进行了交通调查,在对比分析调查数据的基础上,从行人过街效率、机动车通行效率以及人行横道安全性3个方面,探讨不同的路段人行横道控制方式对交通流的影响。 相似文献
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994.
厦门快速公交系统(BRT)高架车站的设计与施工 总被引:1,自引:0,他引:1
厦门BRT高架车站结构型式是一种新型的车站结构型式,通过对传统高架车站进行体系改变,改善了结构受力状况。该文从结构选型、受力分析以及设计与施工等方面,对这种新型的高架车站进行了详述。 相似文献
995.
996.
Y. S. Kim E. Y. Kim Y. W. Shin S. K. Lee 《International Journal of Automotive Technology》2010,11(5):759-765
This paper presents a multi-body flexible dynamic analysis of a centrifugal turbo blower for a fuel cell electric vehicle
(FCEV) based on the application of computer-aided engineering (CAE) to predict the acceleration at the mount position of the
blower. This predicted acceleration is validated by using the measured acceleration data. The numerical simulation for the
multi-body flexible dynamics of the blower is used not only to identify the most effective mount among four mounts in an FCEV
by controlling the complex stiffness of the isolator, but also to suggest the range of complex stiffness of the isolator at
the most effective mount. This numerical simulation technology can be useful for the estimation of the variation of vibration
transmission for the structural modification of the turbo blower. 相似文献
997.
The importance of vehicle safety cannot be exaggerated in today’s mobile societies. Many manufacturers, associates related
to vehicles and universities make an effort to improve vehicle safety by developing new technologies, applying high strength
steel to the body structure etc. However, the majority of these efforts are focused on decreasing injury. It is absolutely
important to minimize injury, but a more important aspect is coping with vehicle accidents. That is, As undeniably important
as it is to minimize potential injuries, it is critical that experts focus on developing ways to keep drivers out of situations
likely to lead to crashes in the first place. The purpose of this paper is to determine what the most critical factor is when
coping with an unfamiliar driving situation. The answer is to provide a wide-open field of vision, especially for the driver.
The driver’s field of vision is obstructed by the vehicle’s A-pillar. To solve this, the A-pillar obstruction angle, which
is the angle between the driver’s eyes and the A-pillar should be decreased. This paper purposes three-methods for decreasing
this angle structurally and applying a slim A-pillar which is as the best solution to decrease the A-pillar obstruction angle
and ensure the drivers field of vision at the same time 相似文献
998.
This paper explores issues related to the electrical safety of Hybrid Electrical Vehicles (HEVs) during and after various
crash events. Japanese and American federal regulations regarding occupant protection against high voltages in Electric Vehicles
(EVs) and HEVs were surveyed and analyzed in this study. Front, side and rear impact tests for two types of HEVs were conducted
to investigate electrolyte spillage, the retention of the propulsion battery system and the electrical isolation of the occupant.
The test results met the related criteria. The test procedures and the criteria for occupant protection established through
this study were amended to Korean Motor Vehicle Safety Standard (KMVSS) No. 91 to add the crash protection of the EVs and
the HEVs. 相似文献
999.
H. J. Kim B. Han W. S. Hong W. H. Shin G. B. Cho Y. K. Lee Y. J. Kim 《International Journal of Automotive Technology》2010,11(4):447-453
A 3000 cc diesel engine attached to an engine dynamo was used to test three newly developed electrostatic Diesel Particulate
matter filtration Systems (DPS 1, 2, and 3) under four steady-state engine operating conditions: idle, 2000 rpm with no load,
and 2000 rpm under 25% and 50% loads. Of the two developed alternatives, DPS 1 and DPS 2, DPS 2 comprises an ionization section,
electrostatic field additional section and Flow-Through Filter (FTF), which achieved almost 90% removal of particulate matter
(PM) under the engine’s operating conditions, and the efficiency of the FTF was maintained between 20% and 50%. Comparing
the long-term performance of DPS 2 and DPS 3 (effectively a serial combination of two DPS 2s) with a commercially-available
Diesel Particulate Filter (DPF), the DPS 2 and DPS 3 achieved almost the same efficiency for removing PM as the DPF but had
significantly improved (75%∼90% lower) differential pressure drops. 相似文献
1000.
G. -Q. Liu Y. -C. Yan J. Chen F. -F. Xu 《International Journal of Automotive Technology》2010,11(4):573-580
A hydraulic power-assist system is a hydraulic regeneration system that can significantly improve fuel economy when installed
on a conventional bus operating in urban traffic. This paper presents a methodology for matching a new hydraulic power-assist
system (HPA) to a conventional bus. The HPA and the conventional bus were modeled using the AMESim environment. The HPA was
optimized using a simulation-based orthogonal design method with two indexes, the fuel economy and the acceleration performance.
According to the simulation results, the volume of the accumulator was the primary factor affecting fuel economy, and the
gear ratio of the transfer case was the primary factor influencing the acceleration performance. As a result, tradeoffs between
the two indexes are required for a practical operational scenario. Experimental results demonstrated that the optimal HPA
installed on a conventional bus was able to satisfy the acceleration performance requirement of the vehicle and also reduced
fuel consumption by 25 percent. 相似文献