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991.
作为地铁接驳手段的公共自行车使用特性分析 总被引:1,自引:0,他引:1
本文以苏州公共自行车为研究对象,利用刷卡数据及问卷调查数据分析公共自行车作为地铁接驳手段的使用特性.研究发现,地铁型站点公共自行车的用车时长较短且较为离散,与其他类型站点有显著差异.在接驳地铁的出行者中,公共自行车经常使用者的平均学历较高,也非低收入人群.利用离散选择模型分析地铁接驳方式选择行为可知,接驳方式使用时间是最重要的影响因素,年龄、职业和出行目的等对公共自行车的选择均有显著影响.研究还发现,经常使用公共自行车的出行者在接驳地铁时同样也倾向于选择公共自行车,而不使用者则倾向于选择步行或公交车. 相似文献
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To solve the power steering (PS) hose oil leakage problem in automobile applications, a new geometry design of the metal fitting is required, and the swaging conditions applied to the PS hose should be optimized. In this study, a new metal fitting geometry for the PS hose was proposed. A CAE simulation for both the proposed and the conventional metal fittings was conducted, and both the stress and the strain in the PS hose were compared. An experimental verification was also performed with these two different metal fittings. Additionally, the swaging conditions were optimized by the durability cycle time, which was measured in an impulse test of the swaged PS hose. For a more economical production, practical working conditions were also recommended and experimentally verified. 相似文献
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J. -K. Kim E. S. Yim C. H. Jeon C. -S. Jung B. H. Han 《International Journal of Automotive Technology》2012,13(2):293-300
This study examines the cold performance of biodiesel blends in a passenger car and a light duty truck at −16 °C and −20 °C.
Six different types of biodiesels derived from soybean oil, waste cooking oil, rapeseed oil, cottonseed oil, palm oil and
jatropha oil were blended with different volume ratios (B5 (5 vol. % biodiesel — 95 vol. % diesel), B10 and B20). The cold
filter plugging point (CFPP) and the cloud point had an effect on the startability and driveability of both the passenger
car and the light duty truck. The startability and driveability of the passenger car with all biodiesel blends (B5) were generally
good at −20 °C. In the light duty truck, biodiesel blends (B10 and B20) of soybean, waste cooking, rapeseed and jatropha tended
to be good at −20 °C in the startability and driveability tests than the biodiesel blends (B10 and B20) of cottonseed and
palm. In particular, the palm biodiesel blend (B10) failed at −20 °C, and the palm biodiesel blend (B20) also failed at −16
°C in the startability test. The cold flow properties of biodiesel dictate that the length of the hydrocarbon chains and the
presence of unsaturated structures significantly affect the low temperature properties of biodiesel. 相似文献
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The virtual erection simulation system was explained for a steel structure including ship and ocean plant blocks.The simulation system predicted the erection state to optimize any gap or overlap of blocks based on 3-D measurement data.The blocks were modified(cut) on the basis of the simulation result on the ground before erecting them by crane.The re-cutting process was not required and the blocks were erected into a mother ship speedily.Therefore,the erection time is reduced,increasing the dock turnover. 相似文献
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针对利用地震波场对目标进行探测问题,研究了利用地震波勘探的基本原理,提出了采用小波变换对地震波信号进行降噪的方法,通过与传统的经典滤波方法相比,小波变换降噪方法在去除掉高频噪声的同时保留了信号的高频成分,是一种比傅立叶变换更有效的降噪方法。对比了几种小波去噪的方法,从不同的性能指标中优化出针对地震波信号的环境特点最为有效的降噪方法,从而达到有效提取有用信号并探测目标的目的。 相似文献