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231.
Central to the concept of Transit Oriented Development (TOD) is a retail core situated around stations. However, successful retail near light rail transit stations has been elusive. Despite significant implications for land use, transportation, and economic development planning, little research exists to explain the gap between TOD concept and reality. We hypothesize that the density, diversity, and design characteristics central to the theory of TODs drive retail success. We implement a TOD Index proposed in the literature to score 474 light rail station areas in 11 metropolitan areas according to the presence and magnitude of those density, diversity, and design characteristics. A series of robustly-developed multilevel models support our hypothesis: TOD Index scores significantly predict station area retail employment, ceteris paribus. An evaluation of its subcomponents individually (block size, which relates to walkability; land use mix; and activity density) suggests activity density may be the driving force in this relationship. Our research works to move the conversation away from an assumption that transit stations and retail naturally co-exist and toward more intentional station area design choices demonstrated to drive retail employment. 相似文献
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本控制器以STC89C51RC微控制器核心,采用Proteus和Keil C51进行硬件电路设计和软件设计、C51编程,开发了一款高性价比的新能源汽车制动灯控制器,并在Proetus环境中进行了软、硬件联合仿真、测试与验证。 相似文献
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本文介绍了汽车防抱制动系统的基本原理、建立了车辆制动系统的数学模型及模糊控制算法,并对基于滑移率的模糊控制防抱制动系统进行了计算机仿真研究。 相似文献
236.
为解决树脂基纤维增强汽车制动摩擦片存在的热衰退问题,对其粘结剂进行了改性。通过正交试验,分析了高温下摩擦材料各成分对制动摩擦片热衰退性能的影响,探讨了制动摩擦片的摩擦磨损机理,优化了摩擦材料配方。试验结果表明,采用优化后配方研制的制动摩擦片在高温下具有良好的抗热衰退性能,摩擦因数稳定,磨损率低。 相似文献
237.
隧道内环境封闭路面亮度低,某些照明不足或未设置照明系统的隧道路面行车安全隐患大.明色降噪微表处罩面技术是一种显著提高隧道路面明亮程度改善行车条件的预防性养护方法,它可以提高隧道路面明亮程度以及抗滑性能,同时使用安全节能环保,施工方便.隧道路面通过明色降噪微表处罩面,可以增加隧道内部亮度,提高可视性,有利于行车安全,具有一定的推广应用价值. 相似文献
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Transit development is one planning strategy that seeks to partially overcome limitations of low-density single use car oriented development styles. While many studies focus on how residential proximity to transit influences the travel behaviors of individuals, the effect of workplace proximity to transit is less understood. This paper asks, does working near a light rail transit station influence the travel behaviors of workers differently than workers living near a station? We begin by examining workers’ commute mode based on their residential and workplace proximity to transit station areas. Next, we analyze the ways in which personal travel behaviors differ between those who drive to work and those who do not. The data came from a 2009 travel behavior survey in the Denver, Colorado metropolitan area, which contains 8000 households, 16,000 individuals, and nearly 80,000 trips. We measure sustainable travel behaviors as reduced mileage, reduced number of trips, and increased use of non-car transportation. The results of this study indicate that living near a transit station area by itself does not increase the likelihood of using non-car modes for work commutes. But if the destination (work) is near a transit station area, persons are less likely to drive a car to work. People who both live and work in a transit station area are less likely to use a car and more likely to take non-car modes for both work and non-work (personal) trips. Especially for persons who work near a transit station area, the measures of personal trips and distances show a higher level of mobility for non-car commuters than car commuters – that is, more trips and more distant trips. The use of non-car modes for personal trips is most likely to occur by non-car commuters, regardless of their transit station area relationship. 相似文献
240.
当传统汽车减速或制动时,车辆运动能量通过制动系统而转变为热能释放到大气中。而新能源汽车通过制动能量回收技术转变为电能储存于蓄电池中,从而提高车辆的续驶能力。新能源汽车在制动过程中,要保证其制动稳定性和平稳性,同时要尽可能多地回收制动能量,以延长新能源汽车续驶里程。文章通过对制动能量回收系统的定义、组成及工作原理进行研究,剖析了新能源汽车电机再生制动能量回收工作过程和制动能量回收系统的制动工作过程,阐明了制动能量回收系统各部件的作用;重点围绕途观L PHEV制动系统组成、途观L PHEV制动能量回收系统混合制动工作原理,即减速请求、摩擦减速、再生减速的支持及三相电流驱动装置的支持不足4个工作过程;系统地介绍了TiguanLPHEV制动能量回收系统主要是通过控制机电式制动助力器e-BKV和蓄压器VX70实现的,驾驶员的减速请求是摩擦减速与能量回收减速的综合。 相似文献