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排序方式: 共有1956条查询结果,搜索用时 15 毫秒
831.
GSM—R系统能够提高运输效率、保证行车安全、改善运营质量。从系统构成、系统功能和系统业务等方面介绍了GSM—R无线通信系统在大秦铁路的应用情况。 相似文献
832.
地铁交通引起地面振动的实测与分析 总被引:15,自引:0,他引:15
根据现场实测数据,对某地铁1号线沿线典型区段地铁引起的地面振动实况和振动特性及其传播规律等进行了分析研究。结果表明:地铁诱发地面振动的振级主要由测点到轨道中心的水平距离决定,并且在离开地铁隧道中心线一定距离范围内,存在一个振动放大区;地面振动存在一个主要的响应频带,在此范围内的建筑物若其自振周期处于这一频带,则会受到地铁交通的显著影响。此外,还对地面振动实测资料进行评价分析,为评估地铁运营诱发的环境振动与城市规划设计提供参考。 相似文献
833.
新密—商丘地方铁路的扩能改建,是河南省东西部矿产资源交流、扩大铁路运输市场份额、完善区域铁路路网的需要,能够为国铁新郑站、商丘站集散运量,增强铁路企业的运输竞争力,减轻国铁郑州枢纽铁路的“瓶颈”压力。该扩能改建项目要积极争取沿线各级地方政府的支持和优惠,吸引沿线各类社会投资,按照现代企业制度组建合资铁路公司并进行规范化运作。 相似文献
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836.
装配式管片接头受力平面有限元分析 总被引:3,自引:0,他引:3
在盾构法隧道设计中,评价接头刚度对管片内力的影响是隧道设计的一个十分重要的内容.由于管片接头或整环管片试验资料过少,很难得到普遍性的接头刚度规律.目前工程中大多根据经验将接头刚度确定为某一常数.针对上述问题,文章通过对广州地铁三号线无传力衬垫的盾构隧道管片接头进行了接触问题的非连续弹塑性有限元分析,得出了接缝转角与弯矩的关系曲线.这种关系曲线接近双直线形状,因此可以简化为双直线关系来确定接头刚度.计算的结果反映出管片接头转角与管片内力之间的非线性关系的规律,为管片设计中的关键参数选择提供了依据,具有较大的实用和参考价值. 相似文献
837.
Online license plate matching procedures using license-plate recognition machines and new weighted edit distance 总被引:1,自引:0,他引:1
Francisco Moraes Oliveira-NetoLee D. Han Myong K. Jeong 《Transportation Research Part C: Emerging Technologies》2012,21(1):306-320
License-plate recognition (LPR) technology has been widely applied in many different transportation applications such as enforcement, vehicle monitoring, and access control. Recently, there has been effort to exploit an LPR database for vehicle tracking using popular template matching procedures. Existing template matching procedures assume that the true reference string is always available. However, under a two-point LPR survey, a vehicle could have its plate misread at both locations generating a pair of misread strings (or templates) with no reference for matching. To compensate for LPR misreading problem, we propose a new weight function based on a probability model to match the observed outcomes of a dual LPR setup. Also, considering that reversal errors are never made in LPR machines, new editing constraints as a function of the string lengths are proposed to avoid compensation for reversal errors. These editing constraints are incorporated into the constraint edit distance formulation to improve the performance of the matching procedure. Finally, considering that previous template matching procedures do not take advantage of passage time information available in LPR databases, we present an online tracking procedure that considers the properties of probability distribution of vehicle journey times in order to increase the probability of correct matches. Experimental results show that our proposed procedure can improve the accuracy of LPR systems and achieve up to 97% of positive matches with no false matches. Further research is needed to extend the ideas proposed herein to plate-matching with multiple, i.e., more than two, LPR units. 相似文献
838.
B. Suh A. Frank Y. J. Chung E. Y. Lee Y. H. Chang S. B. Han 《International Journal of Automotive Technology》2010,11(4):555-563
This research is the first to develop a design for a powertain system of a plug-in parallel diesel hybrid electric bus equipped
with a continuously variable transmission (CVT) and presents a new design paradigm of the plug-in hybrid electric bus (HEB).
The criteria and method for selecting and sizing powertrain components equipped in the plug-in HEB are presented. The plug-in
HEB is designed to overcome the vulnerable limitations of driving range and performance of a purely electric vehicle (EV)
and to improve fuel economy and exhaust emissions of conventional bus and conventional HEBs. The control strategy of the complicated
connected propulsion system in the plug-in parallel HEB is one of the most significant factors in achieving higher fuel economy
and lower exhaust emissions of the HEV. In this research, a new optimal control strategy concept is proposed against existing
rule-based control strategies. The optimal powertrain control strategy is obtained through two steps of optimizations: tradeoff
optimization for emission control and energy flow optimization based on the instantaneous optimization technique. The proposed
powertrain control strategy has the flexibility to adapt to battery SOC, exhaust emission amount, classified driving pattern,
driving condition, and engine temperature. The objective of the optimal control strategy is to optimize the fuel consumption,
electricity use, and exhaust emissions proper to the performance targets. The proposed control strategy was simulated to prove
its validity by using analysis simulation tool ADVISOR (advanced vehicle simulator). 相似文献
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