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51.
集装箱班轮运输业如何在追求成本经济性和服务可靠性的同时做好环境可持续性,对航 运企业、港口运营商以及政府组织都提出了新的挑战。围绕集装箱班轮运输在环境层面实现可 持续发展的目标,本文分别从战略、战术和运营等3个层面就措施、技术和规章制度等所做的研究 进行文献综述、分析发展趋势。战略层面,从市场减排机制和政策的制定、绿色政策、技术及措施 评估和企业竞争与合作等3个方面综述;战术层面,从控制油耗或碳排放的班轮运营优化、预调度 式的绿色班轮运营优化和污染排放控制区的设立对班轮运营优化的影响等3个方面综述;在运营 层面,从控制排放的集装箱调运和反应式的绿色班轮运营优化等两方面综述。按照决策水平、时 间脉络和研究主题分析后发现,该领域的研究趋势变化与行业及政府的环境政策紧密关联。其 次,从决策水平和问题类别来看,针对战术层决策的研究远多于针对战略和执行两层。第三,从 决策主体来看,大部分研究以航运公司作为单独的决策主体。本文建议:继续在优化班轮运输中 考虑多目标,将多目标优化作为决策手段可兼顾经济、环境以及社会责任,有利于航运可持续发 展;结合行业实践提炼科学问题,国际航运、尤其班轮运输极易受到政策导向、世界经济环境的影 响;从供应链角度研究集装箱班轮运输的可持续发展问题;为配合在运营层面的努力,还要研究 通过技术途径或手段推动班轮运输业可持续发展;借鉴其他运输行业较为成熟的绿色环保发展 思路促进班轮运输环境可持续发展。  相似文献   
52.
通过安装车载测试系统收集香港港岛山区路段正常行驶工况下尾气中的CO、NOx、HC等污染物和油耗并辅助计算机软件进行分析。研究得出,山区道路设计、地形地貌和驾驶习惯对车辆油耗以及CO、NOx和HC排放有直接关系。可以通过坡道加宽、坡道延长、减少坡道红绿灯等措施减少车辆在山区道路行驶过程中速度变化频率,从而减少油耗以及CO、NOx和HC排放。  相似文献   
53.
The European Clean Vehicle Directive was introduced in 2009 to create an obligation on public authorities to take into account the impact of energy consumption, carbon dioxide (CO2) emissions and pollutant emissions into their purchasing decisions for road transport vehicles. This should stimulate the market for clean and energy-efficient vehicles and improve transport's impact on environment, climate change and energy use. Therefore the so-called ‘Operational Lifetime Cost’ of a vehicle is calculated, divided into the cost for energy consumption, CO2 and pollutant (nitrous oxide, particulate matter, non-methane hydrocarbons) emissions. In Belgium, a different methodology has been developed to calculate the environmental impact of a vehicle, called ‘Ecoscore’, based on a well-to-wheel approach. More pollutants are included compared to the Clean Vehicle methodology, but also indirect emissions are taken into account. In this paper, both methodologies are compared and used to analyze the environmental performance of passenger cars with different fuel types and from different vehicle segments. Similar rankings between both methodologies are obtained; however, the large impact of energy use (and CO2 emissions) in the Clean Vehicle methodology disadvantages compressed natural gas cars, as well as diesel cars equipped with particulate filters, compared to the Ecoscore methodology.  相似文献   
54.
Significant effects of traffic congestion include the cost associated with extra travel time, fuel consumption, and gas emissions. This paper develops a mathematical function to quantify the monetary impact of transition designs between signal timing plans on users and the environment. This function offers an approach to reduce problems such as excessive travel time, pollution emissions and fuel consumption. The proposed social cost function is evaluated for various transition plans to assess the impact of the number of steps required to adjust signal timing. The relationships between delay, fuel consumption and gas emissions and the number of steps needed to achieve the transition are also analysed.  相似文献   
55.
Exhaust emissions cause air pollution and climate change. The exhausts of shipboard fuel combustion are equally damaging particularly, so close to the environmentally sensitive mainland and island coasts, as well as at ports due to their urbanized character. This paper estimates, for the first time, exhaust pollutants related to cruise and ferry operations in Las Palmas Port and, in an island context. Emission assessment is based on a full bottom-up model and messages transmitted by the Automatic Identification System during 2011. Results are described as a breakdown of NOx, SOx, PM2.5, CO and CO2, according to ship classes, operative type and time, providing valuable information to environmental policy makers in port-city areas and islands under similar conditions. It is generally concluded that vessel traffic and passenger shipping in particular are a source of air pollution in Las Palmas Port. Emission maps confirm location of hot spots in quays assigned for cruise and ferry operations. Policy recommendations encourage regular monitoring of exhaust emissions and market-based incentives supported by details on polluting and operative profiles. On the other hand, feasibility studies are suggested for automated mooring, LNG bunkering facilities and also shore-side energy services, prioritizing berthing of shipping sectors (or sub-sectors) with the highest share of exhaust emissions once their local effects have been confirmed by a dispersion, exposure and impact assessment.  相似文献   
56.
This paper proposes a novel short/medium-term prediction method for aviation emissions distribution in en route airspace. An en route traffic demand model characterizing both the dynamics and the fluctuation of the actual traffic demand is developed, based on which the variation and the uncertainty of the short/medium-term traffic growth are predicted. Building on the demand forecast the Boeing Fuel Flow Method 2 is applied to estimate the fuel consumption and the resulting aviation emissions in the en route airspace. Based on the traffic demand prediction and the en route emissions estimation, an aviation emissions prediction model is built, which can be used to forecast the generation of en route emissions with uncertainty limits. The developed method is applied to a real data set from Hefei Area Control Center for the en route emission prediction in the next 5 years, with time granularities of both months and years. To validate the uncertainty limits associated with the emission prediction, this paper also presents the prediction results based on future traffic demand derived from the regression model widely adopted by FAA and Eurocontrol. The analysis of the case study shows that the proposed method can characterize well the dynamics and the fluctuation of the en route emissions, thereby providing satisfactory prediction results with appropriate uncertainty limits. The prediction results show a gradual growth at an average annual rate of 7.74%, and the monthly prediction results reveal distinct fluctuation patterns in the growth.  相似文献   
57.
提出一种客货滚装码头减排设计方案评价方法.在综合考虑成本属性、环境属性、社会属性构建方案评价指标体系的基础上,引入层次分析法和加权TOPSIS法对客货滚装码头减排设计方案进行综合评价,并以某拟建客货滚装码头为例验证方法的有效性.结果表明,算例中各方案在评价模型下具有良好的区分度,方案从优到劣为岸电、低硫柴油和陆基洗涤器...  相似文献   
58.
当前形势表明,碳治理的紧迫性从未像现在这样明确而迫切。城市道路交通领域在按时达成预定碳目标方面仍面临重大挑战。为理清各种措施、路径或方法之间的关系,构建一个明晰的治理框架,并把握研究与实践的关键路径,以便于更有效的碳中和行动。通过运用文献研究、统计分析和归纳与演绎等多种方法,研究并提出了城市道路交通系统性解决方案和碳中和措施分系统的基本架构,明确了从系统、分系统、子系统到关键组件的关键线路,对碳中和措施分系统中的两类主要负排放措施进行了深入的分析,并强调了负排放子系统在城市道路交通实现零碳排状态中的决定性作用。其结论可为其他行业或领域的碳中和措施系统构建提供借鉴和参考。  相似文献   
59.
主要研究了当运输时间、中转时间、客户需求和中转集拼货运量四重混合不确定因素服从随机分布时的绿色多式联运路径优化问题,运用随机优化理论,以运输成本、碳排放成本和时间惩罚成本为目标,建立混合不确定条件下绿色多式联运路径优化模型.通过对各子目标函数权重进行赋值,得出考虑不同成本因素的多式联运路径优化方案.探讨时间、需求和网络服务能力对多式联运路径优化结果的灵敏度分析,发现各成本随时间变动而变化的规律和边际运输成本最小时的服务时间;当货运量形成规模效应后可降低边际运输成本;不同网络服务规模的运输路径优化结果,以及满足客户不确定需求的最小网络配置.  相似文献   
60.
谐振进气改善增压中冷柴油机性能和排放的研究   总被引:3,自引:0,他引:3  
自行设计了适合于车用增压中冷柴油机的谐振进气系统,试验研究了谐振进气对柴油机燃油消耗率(b)、充量系数(c)、排气烟度(Rb)、PM等气体排放物的影响。结果表明,采用谐振进气系统可有效改善增压中冷柴油机的低速性能。合理匹配谐振系统参数,在低于谐振转速的工况范围内,可有效提高增压中冷柴油机的进气充量,增加空燃比(α),降低b和Rb。采用谐振箱容积为1.83 L、谐振管直径为50 mm、谐振管长度为1.1 m的谐振系统,与原机相比,低速工况c提高5%,Rb降低33%,同时有效降低了CO及PM排放。  相似文献   
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