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261.
刘菁华 《铁道标准设计通讯》2019,(2):131-136
为了提升铁路沿线城市空间物业开发的设计手法,结合宝鸡市南客站核心区站前广场工程的设计实践,从系统性设计观、工程性质解析、消防设计思路、空间建构方法、无缝接驳、技术要素等方面进行研究分析,展示将铁路与城市系统进行一体化设计、利用自然资源解决消防和投资问题、平层空间中对多种交通体系的有机组织、不同坐标和高程系统背景下分区域构建柱网、各板块交接处的问题解决等技术成果,总结出同类型建筑的设计思路,力求为该领域的建筑设计发展提供有益的借鉴。 相似文献
262.
研究分析涂装设计工艺流程、涂装生产管理流程及涂装机器人工艺参数,整理分析涂装工艺数据、生产管理信息和涂装机器人的工艺特征,对这些数据进行整理归纳,理清他们之间的逻辑关系,形成数据接口,通过数据库系统完成涂装规范化设计和生产管理以及涂装机器人的对接。 相似文献
263.
The High Line is an elevated public park in New York City, transformed from an unused freight rail line. Pedestrians walking through Manhattan’s West Side can walk either on the High Line or on a footpath below. Using Manhattan as a laboratory, this paper offers a combined assessment of noise and particulate matter pollution for its pedestrians. Noise and PM2.5 levels were recorded simultaneously for two cases (i) pedestrians walking on a footpath alongside road traffic and (ii) pedestrians walking on the elevated High Line. Testing took places over three days in autumn 2014. Results were analysed to investigate if pedestrians using the High Line would have a lower pollution exposure to those using the footpath below. Results showed statistically significant differences between the upper and lower levels in exposure to both pollution types. In order to quantify the overall impact, results are expressed through a combined air–noise pollution index. This index indicates that the average reduction in PM2.5 and noise pollution along the High Line compared to the footpath below is approximately 37%. 相似文献
264.
265.
文章主要介绍了海洋平台常用流量计的原理和特点,结合海洋平台的特点叙述了流量计选型时的注意事项,并给出了海洋平台常用流量计的选型原则和计算方法,为海洋平台选出最合适的流量计提供了一种方案。 相似文献
266.
This study investigates the cost competitiveness of different types of charging infrastructure, including charging stations, charging lanes (via charging-while-driving technologies) and battery swapping stations, in support of an electric public transit system. To this end, we first establish mathematical models to investigate the optimal deployment of various charging facilities along the transit line and determine the optimal size of the electric bus fleet, as well as their batteries, to minimize total infrastructure and fleet costs while guaranteeing service frequency and satisfying the charging needs of the transit system. We then conduct an empirical analysis utilizing available real-world data. The results suggest that: (1) the service frequency, circulation length, and operating speed of a transit system may have a great impact on the cost competitiveness of different charging infrastructure; (2) charging lanes enabled by currently available inductive wireless charging technology are cost competitive for most of the existing bus rapid transit corridors; (3) swapping stations can yield a lower total cost than charging lanes and charging stations for transit systems with high operating speed and low service frequency; (4) charging stations are cost competitive only for transit systems with very low service frequency and short circulation; and (5) the key to making charging lanes more competitive for transit systems with low service frequency and high operating speed is to reduce their unit-length construction cost or enhance their charging power. 相似文献
267.
268.
阐述了基于云平台的城市轨道交通能源管理系统架构和建设方式。该系统利用云计算的高效和弹性来部署建设,采用线网-车站二层管理模式,降低了线网和线路服务器等的硬件部署成本和维护成本。通过将能源管理系统内部使用的业务应用转换为基于云平台的能源管理应用软件,能源管理系统可获取云平台提供的共享数据,并将经过业务处理后的数据存储到云平台中,以服务于云平台上其他业务,实现了数据资源的逻辑统一和高效利用。 相似文献
269.
270.
Building safe and effective roundabouts requires optimizing traffic (operational) efficiency (TE) and traffic safety (TS) while taking into account geometric factors, traffic characteristics and local constraints. Most existing simulation-based optimization models do not simultaneously optimize all these factors. To capture the relationship among geometry, efficiency and safety, we put forward a model formulation in this paper. We present a new multi-criteria and simultaneous multi-objective optimization (MOO) model approach to optimize geometry, TE and TS of urban unsignalized single-lane roundabouts. To the best of our knowledge, this is the first model that uses the multi-criteria decision-making method known as analytic hierarchy process to evaluate and rank traffic parameters and geometric elements of urban single-lane roundabouts. The model was built based on comprehensive review of the research literature and existing roundabout simulation software, a field survey of 61 civil and traffic expert engineers in Croatia, and field studies of roundabouts in the Croatian capital city of Zagreb. We started from the basis of Kimber’s capacity model, HCM2010 serviceability model, and Maycock and Hall's accident prediction model, which we extended by adding sensitivity analysis and powerful MOO procedures of the bounded objective function method and interactive optimization. Preliminary validation of the model was achieved by identifying the optimal and most robust of three geometric alternatives (V.1-V.3) for an unsignalized single-lane roundabout in Zagreb, Croatia. The geometric parameters in variant V.1 had significantly higher values than in the existing design V.0, while approaches 1 and 3 in variant V.2 were enlarged as much as possible within allowed spatial limits and Croatian guidelines, reflecting their higher traffic demand. Sensitivity analysis indicated that variant V.2 showed the overall highest TE and TS across the entire range of traffic flow demand and pedestrian crossing flow demand at approaches. At the same time, the number of predicted traffic accidents was similar for all three variants, although it was lowest overall for V.2. The similarity in predicted accident frequency for the three variants suggests that V.2 provides the greatest safety within the predefined constraints and parameter ranges explored in our study. These preliminary results suggest that the proposed model can optimize geometry, TE and TS of urban single-lane roundabouts. 相似文献