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991.
992.
城市环路快速系统的设计具有许多不同于一般城市道路的特点,该文在对二环交通问题进行分析的基础上,阐述了二环快速系统的功能定位和设计标准,介绍了昆明市主城二环快速系统的总体设计,总结和探讨了快速环路设计中的总体思路、立交选型等关键性技术问题。 相似文献
993.
Under the Connected Vehicle environment where vehicles and road-side infrastructure can communicate wirelessly, the Advanced Driver Assistance Systems (ADAS) can be adopted as an actuator for achieving traffic safety and mobility optimization at highway facilities. In this regard, the traffic management centers need to identify the optimal ADAS algorithm parameter set that leads to the optimization of the traffic safety and mobility performance, and broadcast the optimal parameter set wirelessly to individual ADAS-equipped vehicles. Once the ADAS-equipped drivers implement the optimal parameter set, they become active agents that work cooperatively to prevent traffic conflicts, and suppress the development of traffic oscillations into heavy traffic jams. Measuring systematic effectiveness of this traffic management requires am analytic capability to capture the quantified impact of the ADAS on individual drivers’ behaviors and the aggregated traffic safety and mobility improvement due to such an impact. To this end, this research proposes a synthetic methodology that incorporates the ADAS-affected driving behavior modeling and state-of-the-art microscopic traffic flow modeling into a virtually simulated environment. Building on such an environment, the optimal ADAS algorithm parameter set is identified through a multi-objective optimization approach that uses the Genetic Algorithm. The developed methodology is tested at a freeway facility under low, medium and high ADAS market penetration rate scenarios. The case study reveals that fine-tuning the ADAS algorithm parameter can significantly improve the throughput and reduce the traffic delay and conflicts at the study site in the medium and high penetration scenarios. In these scenarios, the ADAS algorithm parameter optimization is necessary. Otherwise the ADAS will intensify the behavior heterogeneity among drivers, resulting in little traffic safety improvement and negative mobility impact. In the high penetration rate scenario, the identified optimal ADAS algorithm parameter set can be used to support different control objectives (e.g., safety improvement has priority vs. mobility improvement has priority). 相似文献
994.
本文为解决某型水缸导轨腐蚀问题,提出了导轨灌胶填充设想,根据设想开展了导轨灌胶工艺方案、工艺流程、检测方案等工程应用研究,并进行了验证试验,以验证导轨灌胶填充工艺工程应用的可行性。针对导轨灌胶填充工艺试验中所出现的问题进行了分析,提出后续改进建议,可为水缸导轨防腐工程应用提供参考依据。 相似文献
995.
The increasing worldwide production of passenger cars depletes natural resources and increases the number of end-of-life vehicles (ELVs) to be processed. Lack of landfill capacity and a growing scarcity of natural resources have lead to severe ELV reuse and recovery targets in the European Union (EU). This paper examines the main influencing parameters affecting the amount and composition of ELV waste originating from passenger cars to be treated in Authorized Treatment Facilities (ATFs). Moreover the effect of a changing number, composition and life span of passenger cars on the ability to meet the ambitious EU ELV Directive 2000/53/EC targets in 2015 is examined for Belgium. Using system dynamics, the aforementioned changing parameters are studied from 1990 and projected to 2030. The model results show that the total annual weight of ELV waste to be reused and recycled in Belgium is expected to grow over the coming years despite the economic downturn of 2008 and its effect on GDP growth. Moreover it shows that Belgium can sustainably achieve the ambitious EU ELV Directive 2000/53/EC targets in 2015 and thereafter if it continues to invest in waste treatment of ELV plastics. The availability of higher amounts of ELV plastics proves to be favourable to trigger investments in their reusing and recycling. We demonstrate that this can be realized by reducing export of discarded passenger cars, shortening the life span of passenger cars or shortening the time for investing in additional plastic recovery. 相似文献
996.
介绍了鱼雷雷伞系统空中弹道多窗口动态显示的基本原理;分析了软件系统开发中的坐标变换、多窗口处理、鱼雷、降落伞和直升机的子图生成及旋转、动画处理等技术关键;论述了系统的面向对象设计方法。 相似文献
997.
998.
本文提出了一种新的能实时预报船用发动机主轴系统扭转振动的精确测量方法.首先,根据脉冲填充法的原理,在主轴作匀速转动的条件下,推导了一个用于精确计算齿脉冲发生时刻主轴系统扭振振幅的理论公式.然后,由该式建立了实时求取主轴系统扭振数据的递推算法,并给出了测量主轴平均转速的公式.文中也对扭振算法的基本误差和主轴转速变化的影响进行了讨论.最后给出了一个基于FPGA实现本算法的硬件电路,并使用动态系统仿真工具SystemView对其工作性能进行了模拟和评价.结果表明:理论计算与实验数据有良好的吻合. 相似文献
999.
1000.
就BEN7.16全液压履带式装载机在使用中出现的两种故障,通过对其制动系统和行驶系统的逻辑关系和工作原理的详细介绍,分析了故障原因是由于对系统不能正确使用和维修所造成的,并提出了解决办法。 相似文献