Particulate matter concentrations and heavy metal contamination levels in the railway transport system of Sydney,Australia

Sampling campaign was conducted over six weeks to determine particulate matter (PM) concentrations from Sydney Trains airport line (T2) at both underground and ground levels using DustTrak. Dust samples were collected and analysed for 12 metals (Fe, Ca, Mn, Cr, Zn, Cu, Pb, Al, Co, Ni, Ba and Na) by atomic emission spectroscopy. Average underground PM₁₀ and PM_2.5 concentrations from inside the trains were 2.8 and 2.5 times greater than at ground level. Similarly, PM₁₀ and PM_2.5 concentrations on underground platforms were 2.7 and 2.5 times greater than ground level platforms. Average underground PM concentrations exceeded the national air quality standards for both PM₁₀ (50 µg/m³) and PM_2.5 (25 µg/m³). Correlation analysis showed a strong to moderate association between PM concentrations at ground level and background PM concentrations (r² from 0.952 to 0.500). The findings suggested that underground PM concentrations were less influenced by the ambient background than at ground level. The metal concentrations decreased in the order of Fe, Cr, Ca, Al, Na, Ba, Mn, Zn, Cu, Ni, Co and Pb. The pollution index (PI) and enrichment factor (EF) values were calculated to identify the levels and sources of contamination in the underground railway microenvironments. PM was remarkably rich in Fe with a mean concentration of 73.51 mg/g and EF of 61.31, followed by Ni and Cr. These results noticeably indicated a high level of metal contamination in the underground environments, with the principal contribution from track abrasion and wear processes.     

A Delphi analysis on green performance evaluation indices for ports in China

This study identified a set of applicable and practical green performance evaluation indices for Chinese ports using the Delphi technique. The research was conducted by targeting three representative Chinese ports in Eastern China: the Shanghai Port, Ningbo Port, and Qingdao Port. An effective expert panel was structured with direct stakeholders related to green performance, which was based on a sufficient consideration of the unique and the special decision-making system for Chinese ports. Twenty-one green performance indices in six dimensions (i.e. liquid pollution management, air pollution management, noise control, low carbon regulations and energy savings, marine biology preservation, and organization and management) were eventually identified through three rounds of iterations. The identified green performance indices for Chinese ports are highly consistent with the Chinese Government’s environmental policies. Compared with European ports, the green port performance indicators in China are not as comprehensive. The indicators that are strictly consistent with national macro policies and the factors that are more easily seen, heard, and felt were perceived to be more important. From an academic perspective, this study offers a new approach for system establishment and green practice criteria exploration and thus provides a significant basis for further green port studies.     

塞拉利昂Pepel地区淤泥质软土工程地质特性

根据塞拉利昂Pepel地区沿岸港口工程的地质勘察资料,通过对该区域淤泥质软土的物理、力学性质指标进行统计与分析,探讨Pepel地区淤泥质软土的工程地质特性,为该地区港口工程规划和水工建(构)筑物的设计提供必要参考。     

The Evaluation of the 2nd Ocean Plan in Korea: Focused on the Implementing Power of the Plan

There seem to be two types of ocean planning system in the world. First, the federal or united government suggests a basic framework of the plan which is followed by states, countries or areas as shown in the European Union, the United States, Canada, Australia, and so on. Second, a powerful central government prepares a basic ocean plan that guides the following sector plans of the relevant ministries. These cases are shown in Japan, Korea, and China. In Korea, the 2nd Ocean and Fishery Development Plan (OK21, 2011–2020) was made as a comprehensive ocean plan reflecting recent natural and social changes including global warming. The OK21 is declarative in its nature, and so evaluated by its sector plans, which have some specific implementing means such as budgets and manpower, organization, and so on, by the relevant laws. The 2nd OK21 is supported by 21 legally binding sector plans, 14 more than in the 1st plan, thus guaranteeing more effective implementation than in the 1st plan. In addition, most of sector plans are planned to be carried out through the well-coordinated system among the related ministries, thus showing a high degree of implementing efficiency of the plan. Every marine area in the plan, including marine environment, is being supported by more sector plans than before, indicating the equitable development of marine areas in the future. In sum, the 2nd OK21 is expected to show more implementing power due to the well-organized sector plans than in the 1st plan.     

基于车体振动加速度的北京地铁轨道状态管理研究

轨道作为行车基础设备,其状态的好坏对列车运行安全和线路服务质量具有重要影响。车体振动加速度是反映列车运行安全性以及乘客乘坐舒适性的重要数据,是评价轨道设备状态和制定养护维修措施的重要依据。基于北京地铁轨道状态的管理需求,分别在空间和时间维度上建立两个利用振动加速度数据评价轨道状态的指标:超限密集度指标和超限重复度指标。利用北京地铁6号线下行方向两次的轨检车检查数据对这两个指标进行计算,结果表明,这两个指标能够更加客观、合理地评价轨道质量状态,有助于提高养护维修作业的效率和针对性。     

无砟轨道造价指标分析

无砟轨道能满足高速行车的技术要求,已成为客运专线普遍采用的轨道形式,国内高速铁路在经过近几年来的不断摸索和创新后,无砟轨道技术日趋成熟。针对我国铁路已经应用的几种无砟轨道类型,从造价指标的角度,结合轨道结构、施工便利程度、工程量等因素,为无砟轨道类型的比选提供参考依据。     

基于AR模型的填方路基沉降检评方法

通过运用数理理论之AR模型,开展填方路基沉降的检评工作,完成了工后质量评定任务,并预测其未来的沉降程度及趋势.研究表明:应用数理理论方法得出的结论,不仅具有实用价值和增强了可靠性,而且兼有鲜明的主动、事前的特征.     

轮机模拟器中机舱资源管理培训及评估功能

通过认可的轮机模拟器对船员进行机舱资源管理培训及评估是满足《STCW公约马尼拉修正案》要求的有效且容易实施的重要手段.在研究了公约中关于机舱资源管理的主要原则、评估手段及评价标准的基础上,深入剖析了船舶机舱资源的基本类型及其特点,并结合轮机模拟器开发过程阐述了相应模块的功能和具体培训及评估实施方法.     

广东软粘土物理力学指标相关性分析

对广东省13条高速公路软粘土的物理力学指标进行了相关性分析,给出了相关公式。分析结果表明:含水率、孔隙比、密度之间线性相关性非常显著;压缩系数与含水率、孔隙比、密度之间呈现良好的幂函数关系;强度指标与物理指标之间相关性较差;力学参数指标间基本无相关关系。     

闸墙碰撞分析及其混凝土性能指标研究*

针对Ⅲ级船闸,采用有限元方法分析闸室墙面遭受设计最大吨级船舶以最大碰撞角度和规范规定的最大航速碰撞闸墙时的内部应力分布情况,发现闸室混凝土结构采用常规的C25强度等级不足以保证闸墙表面承受碰撞时引起的压应力和拉应力.同时,依据有限元分析结果得到闸墙混凝土需要满足的各项强度指标,并且通过实际工程的现场试验研究验证了新老混凝土粘结强度指标的可靠性,为船闸工程设计和结构修复提供可靠依据.