The development of a decision making framework for evaluating the trade-off solutions of cleaner seaborne transportation

The general rise in marine fuel prices in combination with ever-more stringent environmental regulations resulting from IMO conventions and EU Directives have become the main industry drivers for seaborne transportation to become cleaner and more energy efficient. Compliance with existing and soon-to-be-enacted regulations requires evaluating the trade-off between often-conflicting options to select the best available technology or fuel source. Although the traditional way of dealing with this issue has been to apply a cost benefit analysis, this kind of analysis does not adequately consider the complexities of the problem, such as incorporating linguistic preferences or interrelations amongst attributes, experts and their preferences.The challenge in such an analysis corresponds to that of a multiple attribute decision-making problem in which a finite number of alternatives are assessed with regards to a finite number of attributes and experts and ranked from the best to the worst.In this paper, a comprehensive and holistic decision-making framework is proposed to overcome the barriers of cost-benefit analysis techniques, facilitating the inclusion of all possible combinations of decision-making parameters and their discrete values, which will eventually help the industry achieve cleaner seaborne transportation.To demonstrate the applicability of the proposed framework, this paper focuses on a real-life study case involving an environmental compliance problem in the Port of Copenhagen, Denmark, in relation to a particular EU Directive. In conclusion, the proposed framework can be applied as a generalised decision-making model to similar compliance issues encountered within other modes of transportation such as rail and road.     

相干信号源的空间平滑法处理及其效果分析

介绍了相干信号DOA空间平滑技术处理的方法及其效果分析，并给出了处理非相干和相干信号源的仿真结果，实验结果证明了空间平滑技术能够去相干性，达到了对相干信号源的方向进行识别的目的。     

一致L-Lipschitz映象对公共不动点的迭代逼近

Banach空间中非线性算子的不动点的迭代逼近问题是非线性逼近理论中所研究的最重要的问题之一。通常用Mann和Ishikawa迭代法去逼近非线性算子的不动点。本文研究了Banach空间中一致L-Lipschitz映象对公共不动点的迭代逼近问题,改进和推广了文献[5-6]的相应结果。     

数控编程中各位置点的关系及选择技巧

本文指出了在数控编程中必须注意的几个位置点,分析了位置点在编程中的重要地位和作用,并用图示的方法.探讨了各位置点之间的相互关系。     

承重混凝土多孔砖在北方严寒地区多层建筑中的应用

以具体工程为例详细阐述了承重混凝土多孔砖的自身特性，以及在北方严寒地区多层建筑设计和施工中应该注意的控制要点，目的是加强设计和施工质量，以促进混凝土多孔砖的长远发展。     

地铁车站人群集散能力瓶颈风险评价

城市轨道交通日益增长的需求与有限的地铁站空间之间的矛盾日益加剧,引发地铁站内拥挤位置的人群集散风险评价及人流控制成为亟待解决的问题,提出选取人流密度、关联人群组数和人流负荷率作为瓶颈点风险的评价指标,给定各指标的量化打分方式并制定各得分情况下指标的风险等级。借鉴LED评分法,提出风险值计算公式D=K·N·S以确定人群集散风险等级,为集散管理提供判断依据。结合武汉市洪山广场地铁站乘客流通情况,采用Anylogic仿真模拟得到相关人流参数,根据制定的瓶颈点风险评价标准对其风险进行评价,得出该车站整体集散风险处于中等水平的结论,并针对结果提出应加强乘客引导,增设栏杆分流及增加检票口等风险控制策略。评价结果与实际基本相符,为地铁站内人群集散瓶颈风险评价及控制提供决策依据。     

高速铁路道岔融雪装置的工作原理与应用

结合高速铁路道岔融雪装置的特点,阐述了高速铁路道岔电加热融雪系统的组成、工作原理及主要功能。详细探讨了电加热元件在道岔融雪系统的关键作用,加热元件在设计中如何提高加热效率和速率,如何提高辐射效率等,并结合现场应用情况提出了改进措施,以适应严寒地区铁路道岔融雪的要求。     

大气颗粒物对人体健康影响研究进展

近年来,越来越多的流行病学研究表明,大气颗粒物浓度水平与健康效应终点呈正相关关系。本文对大气颗粒物污染对健康影响的急性和慢性作用的研究进展进行了综述,并分别对颗粒物阈值、质量浓度和计数浓度对人体健康影响以及贫困在颗粒物污染健康影响中的作用这3个热点问题进行了讨论,最后提出了今后的研究方向。     

Roadway determinants of bicyclist exposure to volatile organic compounds and carbon monoxide

Few studies have quantified relationships between bicyclist exposure to air pollution and roadway and traffic variables. As a result, transportation professionals are unable to easily estimate exposure differences among bicycle routes for network planning, design, and analysis. This paper estimates the effects of roadway and travel characteristics on bicyclist exposure concentrations, controlling for meteorology and background conditions. Concentrations of volatile organic compounds (VOC) and carbon monoxide (CO) are modeled using high-resolution data collected on-road. Results indicate that average daily traffic (ADT) provides a parsimonious way to characterize the impact of roadway characteristics on bicyclists’ exposure. VOC and CO exposure increase by approximately 2% per 1000 ADT, robust to different regression model specifications. Exposure on off-street facilities is higher than at a park, but lower than on-street riding – with the exception of a path through an industrial corridor with significantly higher exposure. VOC exposure is 20% higher near intersections. Traffic, roadway, and travel variables have more explanatory power in the VOC models than the CO model. The quantifications in this paper enable calculation of expected exposure differences among travel paths for planning and routing applications. The findings also have policy and design implications to reduce bicyclists’ exposure. Separation between bicyclists and motor vehicle traffic is a necessary but not sufficient condition to reduce exposure concentrations; off-street paths are not always low-exposure facilities.     

内河交通污染事故的类型及管理措施

从内河交通污染事故的类型和特点、内河交通污染事故的原则和加强内河交通污染事故管理体系构建三个方面对内河交通污染事故管理进行了研究。