逆向物流外部效应及其政府干预研究

逆向物流具有准公共物品的特征,由此决定了它还具有正外部效应和负外部效应．正是由于负外部效应的存在,导致逆向物流系统的资源配置迭不到帕雷托最优状态．本文在界定逆向物流外部效应的基础上,提出了政府干预逆向物流以实现外部效应内在化的措施,指出了政府干预的利弊,并对此过程中政府和企业的博弈关系进行了分析。     

水上安全监督管理长效运行机制的探讨

以广东省水域发生的三起重特大水上交通事故为例,对现有水上安全监督管理体制及传统的监督管理措施进行更深层次的思考,认为引入和实行“引导型政府职能模式”,是目前建立我国水上安全监督管理长效的运行机制的关键．     

浅谈如何做好地方公路建设的环境保护监理

阐述了环保监理工作的重要性以及如何开展环保监理工作.     

Optimal shipment decisions for an airfreight forwarder: Formulation and solution methods

We study the freight forwarder’s shipment planning problem in an airfreight forwarding network where a set of cargo shipments have to be transported to given destinations. We provide mixed integer programming formulations that use piecewise-linear cargo rates and account for volume and weight constraints, flight departure/arrival times, as well as shipment-ready times.After exploring the solution of such models using CPLEX, we devise two solution methodologies to handle large problem sizes. The first is based on Lagrangian relaxation, where the problems decompose into a set of knapsack problems and a set of network flow problems. The second is a local branching heuristic that combines branching ideas and local search. The two approaches show promising results in providing good quality heuristic solutions within reasonable computational times, for difficult and large shipment consolidation problems.     

The effect of uncertainty on US transport-related GHG emissions and fuel consumption out to 2050

The future of US transport energy requirements and emissions is uncertain. Transport policy research has explored a number of scenarios to better understand the future characteristics of US light-duty vehicles. Deterministic scenario analysis is, however, unable to identify the impact of uncertainty on the future US vehicle fleet emissions and energy use. Variables determining the future fleet emissions and fuel use are inherently uncertain and thus the shortfall in understanding the impact of uncertainty on the future of US transport needs to be addressed. This paper uses a stochastic technology and fleet assessment model to quantify the uncertainties in US vehicle fleet emissions and fuel use for a realistic yet ambitious pathway which results in about a 50% reduction in fleet GHG emissions in 2050. The results show the probability distribution of fleet emissions, fuel use, and energy consumption over time out to 2050. The expected value for the fleet fuel consumption is about 450 and 350 billion litres of gasoline equivalent with standard deviations of 40 and 80 in 2030 and 2050, respectively. The expected value for the fleet GHG emissions is about 1360 and 850 Mt CO₂ equivalent with standard deviation of 130 and 230 in 2030 and 2050 respectively. The parameters that are major contributors to variations in emissions and fuel consumption are also identified and ranked through the uncertainty analysis. It is further shown that these major contributors change over time, and include parameters such as: vehicle scrappage rate, annual growth of vehicle kilometres travelled in the near term, total vehicle sales, fuel economy of the dominant naturally-aspirated spark ignition vehicles, and percentage of gasoline displaced by cellulosic ethanol. The findings in this paper demonstrate the importance of taking uncertainties into consideration when choosing amongst alternative fuel and emissions reduction pathways, in the light of their possible consequences.     

从深圳模式看我国电子政务的发展

从深圳市出台的电子政务标准化暂行办法出发,对加强政务资源整合,消除电子壁垒,提高办事效率,服务人性化以及努力消除数字鸿沟等方面进行论述,分析了我国电子政务试点城市深圳市电子政务的建设模式,讨论了我国电子政务建设中出现的主要问题,并提出了未来我国电子政务建设的若干发展趋势。     

市场经济中政府规制行为的选择--以解决城市"机动三轮车"运营问题为案例

在我国的大中城市中,机动三轮车运营现象普遍存在。对这些车辆,尤其是在一些大城市中,政府有关部门千方百计地试图加以消灭,可是屡战屡败,而这些运营车辆却生意十分兴隆。为什么会出现这种现象?这种现象怎么会长期存在?本文通过对沈阳市机动三轮车运营情况的实际调查并利用经济博弈论进行一个初步的分析。     

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。     

长江三峡两坝间河段汛期通航试验研究

三峡大坝至葛洲坝两坝间38 km河段是连接三峡库区和葛洲坝下游航道的关键航道。两坝间航道穿行于高山峡谷之中,水流条件复杂,是三峡枢纽涉及的航道中较困难的一段,解决好两坝间的通航问题,是三峡枢纽通航的主要环节。因此,提高两坝间河段通航流量对延长通航期具有重要意义。采用增加推轮推力,改善推轮操纵性能和减驳减载等改进措施,可将两坝间河段的通航流量级由上水的20 000 m3/s,提高到45 000 m3/s。