山区隧道建设中溶洞的处理与利用

岩溶在隧道施工中易引起地质灾害,需对其进行特殊处理。本文从利用角度分析和处理隧道施工中遇到的溶洞问题。结合鸦来公路北风垭隧道施工过程中遇到的溶洞问题,在进行有效处理的同时,将溶洞用于通风排水,既避免了溶洞对施工的不利影响,同时创造了良好的经济效益和社会效益。     

新疆山区公路雪崩灾害防治试验工程效益分析

新疆天气寒冷、降雪量大,公路雪崩灾害频繁发生,严重阻碍了当地经济的发展。结合国道312线果子沟段的试验情况,对防治雪崩的试验工程进行效益分析,并阐述实施雪崩防治工程的必要性和迫切性,对公路雪崩灾害防治是有帮助的。     

基于综合稳定指数的中国金融体系稳定性研究

针对现有文献在度量我国金融稳定性指标体系上的缺陷和不足,文章通过建立一个金融体系的综合稳定指数,以2004年-2011年相关数据为样本对当前我国金融稳定水平进行测度。研究发现2004年以来,我国金融体系总体较稳定,受2008年金融危机影响,我国金融体系在2008年4季度稳定性最弱,2009年稳定性上升,2010年以后我国的金融稳定性又趋于下降。文章度量的金融稳定综合指数与我国的金融运行情况有很高的匹配度。实证分析的结果更进一步验证和说明金融稳定综合指数度量结果的合理性和准确性。     

农村公路财政资金转移支付方式

分析了现有农村公路财政资金转移支付方式的缺陷,以效率与公平为原则,以运输需求与财政能力为目标,提出了一种新的农村公路财政资金转移支付方式。确定了运输需求量和标准交通量,计算了农村公路的投资金额,根据上级政府与下级政府的支付比例与地方政府财政能力,确定农村公路财政资金转移支付金额。运用SPSS统计分析软件,以咸阳市11个区县为例比较了2种支付方式。研究结果表明:2种支付方式的补助金额排名与财政能力排名的相关系数分别为-0.755与0.309,显著度分别为0.007与0.355;运用现有支付方式计算了11个县区的2个指标相近度,2个值为0.50,4个值在[0.20,0.30)之间,剩下的5个值全部小于0.20;运用新的支付方式计算相近度,有2个值为无穷大,1个值为1.00,2个值为0.50,5个值在[0.20,0.30)之间,只有1个值小于0.20。可见,新的支付方式比较合理,兼顾了效率与公平。     

VMS行程时间诱导效益仿真算法

基于宏观交通仿真模型,提出了可变情报板(VMS)行程时间诱导效益仿真算法,分析了驾驶人的信息关注率和信息理解偏差系数对VMS行程时间诱导效益的影响。以行程时间计算模型和驾驶人信息响应模型与METANET仿真模型为理论基础,以路网总耗时改善率为诱导效益目标,在3种不同规模的路网上进行仿真试验。仿真结果表明:VMS行程时间对于改善路网运行效率通常具有正面的诱导效益;信息关注率越高,信息理解偏差系数越小,诱导效益越显著;当信息关注率为80%以上时,小型、中型、大型3种路网的诱导效益分别达到28.89%、15.87%、10.53%以上。可见,仿真算法有效。     

膜生物反应器在高速公路服务区污水处理的应用

合理的污水处理工艺对高速公路服务区的运营发挥着重要的作用。介绍了膜生物反应器工艺（MBR）处理湖南省大围山至浏阳高速公路服务区生活污水的应用。研究表明：MBR工艺的建设成本和日常运行成本较高（分别为3067元／m3和0．74元／m3）,但MBR工艺占地面积少（0．46m2／m3）,出水水质好,可满足城市杂用水回用水质标准,回用水量为38325m3／a,回用水经济效益（114975元／a）是MBR13常运营费用（40515元／a）的2．8倍,COD、SS、BOD和氨氮每年减排量分别为16．43、13．14、7．67,2．19t。因此,尽管MBR工艺的投资费用较高,但是还能够获得更高的环境效益和经济效益回报。这些揭示出采用MBR工艺处理高速公路服务区污水是经济有效和技术合理可靠的,同时也为该行业的废水处理和再生水回用提供了工艺选择方面的参考。     

南京市水阳江水利血防工程措施浅议

介绍了南京市水阳江流域基本情况及疫区基本情况,阐述了水利血防工程的必要性。介绍了该工程的主要建设内容,并阐述了该工程建设对环境的影响和灭螺后的社会经济效益。     

旧沥青路面厂拌热再生利用经济效益分析模型研究

选择国内外有代表性的厂拌热再生设备,从设备生产成本、旧料回收利用成本、再生剂费用、材料节省费用、总体经济效益等5个方面采用收益现值法量化分析了利用厂拌热再生设备再生利用旧沥青路面的经济效益,并在此基础上建立旧沥青路面厂拌热再生利用经济效益分析模型,分析了不同旧料掺配比率时的经济效益差异.     

A simulation approach for estimating value at risk in transportation infrastructure investment decisions

Traditional economic analysis techniques used in the assessment of Public Private Partnership (PPP) projects are based upon the assumption that future cash flows are fully deterministic in nature and are not designed to account for risks involved in the assessment of future returns. In reality, many of these infrastructure projects are associated with significant risks stemming from the lack of knowledge about future cost and benefit streams. The fundamental premise of the PPP concept is to efficiently allocate risks between the public and the private partner. The return based on deterministic analysis may not depict a true picture of future economic outcomes of a PPP project for the multiple agencies involved. This deficiency underscores the importance of risk-based economic analysis for such projects. In this paper, the authors present the concept of Value-at-Risk (VaR) as a measure of effectiveness (MOE) to assess the risk share for the public and private entity in a PPP project. Bootstrap simulation is used to generate the risk profile savings in vehicle operating cost, and in travel time resulting from demand-responsive traffic. The VaR for Internal Rate of Return (IRR) is determined for public and private entity. The methodology is applied to a case study involving such a joint venture in India, the Mumbai Pune Expressway/National Highway 4 (MPEW/NH4), and fiscal implications from the perspective of the public and the private entities are examined. A comparison between deterministic and risk based economic analysis for MPEW/NH4 is presented. Risk analysis provides insightful results on the economic and financial implications from each participant's viewpoint.     

Are Longer and Heavier Vehicles (LHVs) Beneficial for Society? A Cost Benefit Analysis to Evaluate their Potential Implementation in Spain

Abstract

In this paper we carry out a thorough review of the current research related to the benefits and costs arising from the implementation of longer and heavier vehicles (LHVs). From this review we concluded that despite the many studies available, little has been said about the sensitivity of the benefits and costs to the ultimate performance of the key variables related to the evolution of the economy, road transport performance, safety, and so on. In order to fill this gap, we have designed a sensitivity approach based on a cost benefit analysis tool to determine which variables demonstrate the greatest influence on the benefits and costs stemming from the implementation of LHVs. In order to test the methodology, we have used it in an analysis of the Spanish trunk network. The results show that the benefits of LHVs for society are significant. Even in the least favorable scenario, the economic benefits are greater than €3500 million over 15 years, and the environment enhanced as well, for CO₂ emissions are reduced by 2 Million tonnes. Overall we noted how the results are not very sensitive to the evolution of key variables in determining the final outcome. However, we found that the variables that have the greatest affect on the final benefit, such as traffic growth and social discount rate, depend basically on the performance of the overall economy. Moreover, the private cost for haulers seems to be more important in determining the final benefit than externality costs.