基于城市轨道交通衔接规划的方法研究

文章在调研广州轨道交通衔接规划开展情况的基础上,分析广州轨道交通衔接的必要性及轨道交通衔接规划的主要研究内容,提出了衔接方式一体化、区域差别化及站点功能层级化等交通衔接规划的研究方法,为其他城市开展轨道交通衔接规划研究提供参考。     

玻璃钢高速船动力装置设计

针对玻璃钢高速客船的特点,就如何选取主推进柴油机,如何解决机座的强度问题,以及对减小柴油机振动、隔离噪声、防止尾倾过大、控制机舱部位重量等问题进行探讨。通过对名牌柴油机选型、机舱结构优化、环境温度的控制并采取减振措施等,经航行试验实测,动力装置的设计取得较满意的效果。     

Experimental study on the nonlinear pressure acting on a high-speed vessel in irregular waves

The present study focuses on the nonlinear behavior of pressure on the hull surface of a high-speed vessel in irregular waves, particularly the pressure responses of alternately wet and dry areas near the waterline and on the bow zone. The vessel has high deadrise angles that may be subject to slight impact and water pile-up effects. A series of experiments in regular and irregular head waves were conducted, and the validity of applying Volterra modeling was investigated. In a previous article using experimental data in regular waves, it was confirmed that the approximate third-order Volterra model adequately simulated the variation of pressure responses in regular waves of different steepness up to a wave amplitude with a wavelength ratio of 0.01, even for the highly nonlinear pressures acting on the abovementioned areas of the hull surface. In this article, further validation for the second part of the study was obtained using experimental data in irregular waves. The frequency response functions obtained from the previous study’s experimental data in regular waves were applied to the third-order Volterra model by combining the input of irregular waves to simulate the responses in irregular waves of sea state five. Then, the spectra and statistics were analyzed. For the motions, accelerations, and pressure responses in irregular waves (as well as for the simulated time histories) variance spectra and statistics such as cumulative distributions of peak values and probability density functions were compared with the experimental results. It was confirmed that even for highly nonlinear and non-Gaussian pressures on the abovementioned areas of the hull surface, the approximate third-order Volterra model simulates the pressure responses in irregular head waves up to a sea state of five with adequate accuracy on deterministic and statistical bases.     

Can high speed rail offset its embedded emissions?

This paper analyzes the climate implications of investments in high speed railway lines given uncertainty in future transport demand, technology and power production. To capture the uncertainty of estimated parameters, distributions for the annual traffic emissions reduction required to compensate for the embedded emissions from the construction of infrastructure are calculated using Monte Carlo simulation. In order to balance the annualized emissions from the railway construction, traffic volumes of more than 10 million annual one-way trips are usually required. Most of the traffic diverted from other modes must come from aviation and the project cannot involve the extensive use of tunnels.     

津滨轻轨客流特征及功能定位研究

津滨轻轨9号线是连接天津市中心城区和滨海新区的骨干轨道线路,对天津市双城格局的形成起到重要的支撑作用.依托天津市轨道交通AFC票务数据,整理分析津滨轻轨9号线的现状客流特征,包括其客流增长规律和客流的时间、空间分布特征,以及津滨轻轨在地铁5号线开通后,对城区客流服务的增强等内容.基于客流特征,研究分析津滨轻轨现状和规划...