某大型原油船脱硫改装电力系统设计

随着MARPOL公约对船舶在全球海域限制SOX排放量的生效日期日益临近,船舶加装脱硫系统已经成为很多船东的选择。文章以某大型原油船加装脱硫系统的改造项目为背景,对改造后电力系统进行分析研究。为满足船东对船舶航行的燃油经济性要求,该项目确定选用增加脱硫发电机并配脱硫系统配电盘的方案。通过对电力系统进行负荷估算、短路电流计算、选择性分析等,得出此方案不仅可行,同时也最大限度保持了原配电系统完整性。     

Methods for forecasting the market penetration of electric drivetrains in the passenger car market

Current car technologies will not solve upcoming challenges of mitigating greenhouse gas emissions in road transport. Projections of the market penetration by alternative drive train technologies are controversial regarding both forecast market shares and applied scientific methods. Accepting this latter challenge, we provide a (so far missing) overview of methods applied in this field and give some recommendations for further work. Our focus is to classify the applied methods into a convenient pattern and to analyse models from the recent scientific literature which consider the electrification of light-duty vehicles. We differentiate the following bottom-up approaches: Econometric models with disaggregated data (such as discrete choice), and agent-based simulation models. The group of top-down models are subdivided into econometric models with aggregated data (e.g. vehicle stock data), system dynamics, as well as integrated assessment models with general equilibrium models. It becomes obvious that some methods have a stronger methodological background whereas others require comprehensive data sets or can be combined more flexibly with other methods. Even though there is no dominant method, we can identify a trend in the literature towards data-driven hybrid approaches, which considers micro and macro aspects influencing the market penetration of electric vehicles.     

Electric vehicles revisited: a review of factors that affect adoption

Electric vehicles (EVs) were recently reintroduced to the global car market. These are an improvement over their predecessors in performance and electric driving range. Although the uptake of EVs has been notable in a short period of time, most government goals for adoption have not been met. This paper reviews a growing body of peer-reviewed literature assessing factors affecting EV adoption. Several important gaps in knowledge are identified. First, there is mixed evidence of the effectiveness of government incentives in encouraging EV uptake and particularly little knowledge in regards to issues of timing and magnitude. The literature shows that public charging infrastructure is an important factor associated with EV uptake, though the direction of causality is yet unclear. Public charging infrastructure can ease range anxiety, particularly for battery electric vehicles, but there is little guidance as to the way in which government should best go about ensuring the provision of infrastructure. Lastly, the nascent EV market means that studies primarily rely on surveys about hypothetical situations. There is strong evidence that actual purchases are much lower than consumers’ stated preferences. Improving understanding of this “attitude–action” gap is important to better informing studies of EV uptake over time.     

江西省农民收入增长率变动的影响因素分析

相比较于“九五“计划期间,江西省“十五“计划期间农民收入增长缓慢,针对导致这一问题的多种因素,笔者依次采用灰关联度的分析方法,认为当前农村信贷投入是农民增收长效机制的关键所在,并进而指出我省推广小额信贷的重要性及有关注意事项.     

论我国个人所得税的税制改革

阐述了我国个人所得税税制的特征,对个人所得税税制存在的缺陷做了分析,对个税改革的条件、原则和具体措施提出了自己的观点。     

中低收入人群居住地与出行选择行为研究综述

中低收入人群是社会发展过程中具有典型特征的一类特殊群体,而居住与出行是生活质量的核心要素,开展中低收入人群居住与出行选择行为系统综述,对促进城市空间结构优化、改善交通出行环境具有基础作用.本文主要从居住地选择与满意度评估、出行选择行为、居住地与交通出行关联性三个层面,对中低收入群体居住与出行选择行为涉及的关键科学问题、特征指标、分析模型、存在不足进行分析评述.总结发现:相关研究对象上缺少针对中低收入特定人群,研究方法将居住和出行划分为两个系统,宏观空间布局模型与微观行为分析模型相互独立,测量指标以可直接观测的外在变量为主,居民内在主观感受变量考虑不足.最后,提出了未来中低收入群体居住与出行选择行为一体化研究的发展方向.     

城市轨道交通经济可持续发展潜力研究

《国务院办公厅关于进一步加强城市轨道交通规划、建设管理的意见》(国办发[2018]52号)与《国家发展改革委关于加强城市轨道交通规划建设管理的通知》(发改基础[2015]49号)相比,经济部分一个显著变化是将全寿命周期资金保障方案研究前置,并将其作为申报建设规划的必备材料。为更好地协助各城市开展资金保障方案研究工作,从实现城市轨道交通经济可持续发展内外主体——政府和企业角度进行论述,以城市可用财力和城市房价为基础,分别计算各城市可用财力系数和城市房价系数,按政府外部支持与企业内部造血机能各占50%为权重,计算国家批复的43座城市轨道交通项目发展的综合潜力并予以排序。最后以各城市可用财力为基础,分别选用政府可用财力的5%和8%,初步匡定各城市可用于发展城市轨道交通项目出资额,对各城市轨道交通批复规模和发展城市轨道交通潜力的匹配性进行分析,从而为各城市构建合理可行的全寿命周期资金保障方案提供可借鉴的思路。     

京沪高速铁路济南黄河大桥主桥设计

京沪高速铁路济南黄河大桥的主桥桥式方案选择时充分考虑了水文及高速行车对结构的要求,采用刚性梁柔性拱方案。重点介绍了新型带K撑的主桁结构及正交异性整体式桥面在该桥的应用。     

汽油/CNG双燃料发动机的试验研究

将HH368Q汽油机改装成汽油/CNG双燃料发动机,在相同试验条件下,分别对燃用汽油和CNG时的动力性和排放性能进行对比试验,结果表明,改装后的发动机燃用CNG时比燃用汽油时的动力性下降13%;在怠速和中、小负荷工况时排放却比燃用汽油时有明显下降。同时,还对三元催化反应器对燃用CNG时的催化效率和CNG作为代用燃料时发动机存在的问题进行了讨论。     

舰船空调用新型绿色环保制冷剂探讨

目前,我国舰船空调制冷系统基本上都采用R22制冷剂.由于舰船使用的环境恶劣,易造成制冷系统故障,使之每年有相当数量R22制冷剂泄漏于大气中.将舰船空调使用制冷剂R22与几种替代工质进行比较,综合研究和分析环境保护、安全性、热力性质、经济性等因素,提出可替代新型绿色环保制冷剂.