Greenhouse gas emissions from ships in ports – Case studies in four continents

Emissions of GHG from the transport sector and how to reduce them are major challenges for policy makers. The purpose of this paper is to analyse the level of greenhouse gas (GHG) emissions from ships while in port based on annual data from Port of Gothenburg, Port of Long Beach, Port of Osaka and Sydney Ports. Port call statistics including IMO number, ship name, berth number and time spent at berth for each ship call, were provided by each participating port. The IMO numbers were used to match each port call to ship specifications from the IHS database Sea-web. All data were analysed with a model developed by the IVL Swedish Environmental Research Institute for the purpose of quantifying GHG emissions (as CO₂-equivalent) from ships in the port area. Emissions from five operational modes are summed in order to account for ship operations in the different traffic areas. The model estimates total GHG emissions of 150,000, 240,000, 97,000, and 95,000 tonnes CO₂ equivalents per year for Gothenburg, Long Beach, Osaka, and Sydney, respectively. Four important emission-reduction measures are discussed: reduced speed in fairway channels, on-shore power supply, reduced turnaround time at berth and alternative fuels. It is argued that the potential to reduce emissions in a port area depends on how often a ship revisits a port: there it in general is easier to implement measures for high-frequent liners. Ships that call 10 times or less contribute significantly to emissions in all ports.     

第三轨供电系统中受流器与第三轨的接触压力及其对受流性能的影响分析

介绍了第三轨受流器的结构原理。分析比较了弹簧式和气压式受流器与第三轨接触压力调节方式的特点。基于电接触基本理论详细的阐述了受流滑板与第三轨接触区的导电机理。接触区域的导电电路由无数微小的电阻及电容并联而成,接触压力通过影响微小电阻、电容的数量比例,进而影响接触面上的导电能力和磨损性能。标称静态接触压力的设计值接近或等于"法向压应力临界值"时,导电能力和磨损特性取得均衡。     

System energy optimisation strategies for metros with regeneration

Energy and environmental sustainability in transportation are becoming ever more important. In Europe, the transportation sector is responsible for about 30% of the final end use of energy. Electrified railway systems play an important role in contributing to the reduction of energy usage and CO₂ emissions compared with other transport modes. For metro-transit systems with frequently motoring and braking trains, the effective use of regenerated braking energy is a significant way to reduce the net energy consumption. Although eco-driving strategies have been studied for some time, a comprehensive understanding of how regeneration affects the overall system energy consumption has not been developed. This paper proposes a multi-train traction power network modelling method to determine the system energy flow of the railway system with regenerating braking trains. The initial results show that minimising traction energy use is not the same as minimising the system energy usage in a metro system. An integrated optimisation method is proposed to solve the system energy-saving problem, which takes train movement and electrical power flow into consideration. The results of a study of the Beijing Yizhuang metro line indicate that optimised operation could reduce the energy consumption at the substations by nearly 38.6% compared to that used with the existing ATO operation.     

基于DSP的船舶电力推进系统滤波装置控制器设计

小型船舶电力系统中非线性负载多、谐波污染严重.针对这一情况,本文设计一款基于DSP的电力系统滤波装置控制器,该控制器结构简单,稳定性好,实验证明该控制器能有效降低谐波污染,具有一定实用价值.     

基于分级节点的高速铁路货运动车组开行研究

“八纵八横”高速铁路网货运节点可以利用聚类分析法,依据货运总量、GDP、人口、社会消费品零售总额、快递业务量、线路连接数、城市类别和节点类别等指标划分为4个等级。基于灰色系统预测模型,预测2025年高速铁路货运量,构建数学模型计算保本货运量。依据节点划分、货运量预测、保本货运量结果,计算各等级节点中盈利OD所占的比例,结合日均OD量,分析各等级节点间开办高速铁路货运的可行性。研究表明,在一级节点之间可以开行高速铁路货运动车组专列,在二级节点之间可以开行客货联挂动车组,三、四级节点可以采用捎带运输的方式。     

铁路沿线城市空间物业开发研究——以宝鸡市南客站核心区站前广场工程为例

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。     

地铁供电系统中压开关柜电流分析理论和方法

通过分析地铁供电系统不同电压等级的设备电流特征,确定35 kV电压等级设备电流可构造标准曲线,采用机器智能学习算法分析、测算地铁供电系统中各类开关峰谷时段运行电流,以均值-方差方法确定电流的高度异常偏离点,实现异常点数据周期内统计以及实时提醒功能。应用电流实测值分析电流在工作日、节假日的不同曲线,为负荷预测和非正常运行方式下的负荷叠加风险提供预测和评估依据,保障供电系统的安全运行,提高负荷管控效率。     

汉巴南铁路兰渝联络线电分相设置方案研究

联络线电分相设置方案影响因素众多,且其设置与否对工程和运营的影响也较大。本文对汉巴南铁路兰渝联络线电分相设置方案进行研究,提出高速铁路设置关节式电分相联络线最短长度;对联络线电分相不同设置方案进行比选研究,并结合各方案的土建工程、信号系统、供电系统及限制因素提出布局优化措施,以期为联络线电分相合理设置与优化布局提供新思路。     

How the environmental impact affects the design of logistics networks based on cost minimization

The degree of centralization of the logistics network is one of the important strategic decisions to take. This issue has often been studied but mainly from a cost minimization focus. This research studies the influence of incorporating the environmental impact in logistics network design models, comparing the results with those obtained considering cost minimization only. A fuzzy biobjective optimization model is used to carry out a number of experiments. By weighting the relative importance of the two objectives, the differences with respect to the base cost minimization solution can be ascertained. Our results show that in general more material is moved through warehouses when the environmental impact is considered and more decentralized facilities are opened.     

基于PLC的模糊频载调节器设计

介绍可编程序控制器(PLC)实现船舶电站模糊调频调载的软硬件实现方法,采用离线计算、在线查表的方法在PLC上实现模糊控制,利用硬件在环仿真进行试验研究,结果表明,智能频载控制器具有较好的稳、动态性能。