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统计分析了目前使用ZYJ7型转辙机的上海地铁6、7、8、11号线自2008年陆续开通运营以来的故障分类数据,研究了各类故障发生的规律,归纳总结了ZYJ7型转辙机故障发生特点,并指出了各类故障排除方法,为今后设备维护及故障预防提供了一些值得参考的建议.  相似文献   
2.
指出在轨道平顺性测量中轨道检查仪关键器件陀螺仪存在的局限性,通过理论验证,提出一种新的替代方法,即采用传统的长度测量传感器对转角进行测量。通过理论推导,给出新方法的测角数学模型,同时分析了不同基本弦长下其应用的相关问题,以拓展解决此类问题的思路。  相似文献   
3.
With the rapid social and economic development, vehicle emissions have been identified as a major source of urban air pollutions in China. Therefore, the study on vehicle emission estimations is necessary. In light of the limitation of emission data for establishing a local comprehensive emission database, this paper analyzes the characteristics of emission rates in MOVES released by U.S. Environmental Protection Agency (EPA) to investigate the feasibility and to design a method for developing site-specific emission database. Sensitive analysis for model year, age group and speed interval is performed, and the regularity is concluded. The result shows that emission rates are almost constant with model year, but increase with age groups because of emission deterioration. With respect to speed intervals, the emission rates in 25–50 mph are higher than both those <25 mph and >50 mph in the same VSP (vehicle specific power) bins. In addition, an analysis of local emission data in Beijing is conducted to build the relationship between vehicle activities and emission rates. After that, a comparison of emission rates by VSP bins in MOVES and in local database is conducted in this study. The result shows that the absolute values are different because of regulatory emission standards, fuel quality, and other factors. However, the relative changes described by normalizing emission rates have a good consistency. Hence, the regularities of emission rates by VSP bins in MOVES can be used to develop local emission database in Beijing.  相似文献   
4.
基于动力测试手段针对黄土高原典型地区黄土路基试样进行了动力学参数的试验研究。结合已有成果,总结出黄土动力学参数与其主要影响因素具有如下规律:动弹性模量随含水量增大而减小,随着干密度增大而增大;阻尼比随着应变增大而增大,达到某一应变幅值后曲线变缓,趋于一个常值;动粘聚力随含水量增大而明显变小;黄土的动摩擦角当含水量低于塑限时,随含水量的增大而变小,含水量超过塑限后,基本不随含水量变化;黄土动力学参数随地区及采样点的不同而表现出较大差别。  相似文献   
5.
给出了多导单步方法正则性的概念,并给出了多导单步方法具有正则性的条件。  相似文献   
6.
文章依托内蒙古自治区绥满国道主干线博牙高速林场隧道工程,通过设置温度监测断面,对隧道洞内气温及不同部位、不同深度的围岩温度进行了监测分析。结果表明:(1)隧道洞内气温随时间呈三角函数变化;(2)离隧道洞口越远,洞内气温年平均值越高,年温度振幅越小;(3)隧道拱脚处的温度低于边墙、拱腰和拱顶的温度,在隧道未贯通时,拱脚与拱顶最大温差可达3℃。  相似文献   
7.
Let E and F be Banach lattices.It is known that if every continuous linear operator from E into F is regular,then,under some mild assumptions on E or F,either E is lattice isomorphic to an AL-space or F is lattice isomorphic to an AM-space.Here we present a characterization on an AL-space E such that every bounded linear operator from E into a Banach lattice isregular.A counterex.ample is also provided,which shows that the results are unexpected even if the domain is an AL-space or the range space is an AM-space.  相似文献   
8.
相邻桥墩高差过大时,温度效应会引起各桥墩间产生竖向位移差,进而导致轨面产生附加不平顺,对轨道的平顺性及运营安全产生影响。鉴于我国幅员辽阔、地形地貌复杂,部分桥梁相邻桥墩存在较大高差的现象,有必要开展相邻桥墩高差较大时温度效应对不同高度桥墩高程变化的影响研究。采用MIDAS建立有限元模型进行建模,对常见铁路桥梁结构进行分析,并根据计算最终结果,为设计及施工提出指导性建议。  相似文献   
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