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1.
改革开放初期的时候,我和几个年纪稍长的朋友在一起聊天.那哥儿几个下海特早,按当时的标准看,已经可以被称作大款了.不知道是谁先抻的茬儿,说起砍价这件事儿来了.其中有个朋友年纪最大,见多识广,嘴上俏皮话也多.他为砍价这个话题作了一个精辟的总结,"如今这年月,除了公共汽车票不能砍价,剩下的全都能砍价儿."  相似文献   

2.
Tsai  Jyh-Fa  Chu  Chih-Peng 《Transportation》2003,30(2):221-243
The build-operate-transfer (BOT) approach has become an attractive instrument for public facility provision, especially for a project that faces difficulty with public finance. This study analyzes the regulation alternatives on private highway investment under a BOT scheme and their impacts on traffic flows, travel costs, toll, capacity, and social welfare (total user-benefit in the traffic system including congestion). For comparison, five cases are analyzed: (1) No BOT with maximizing welfare, (2) No BOT with breaking even on finance, (3) BOT without regulation, (4) BOT with a minimum flow constraint (the total users will not be less than those in Case 1), and (5) BOT with a maximum travel cost constraint (the travel cost for users on a non-tolled road will not exceed the maximum tolerance). After each case is modeled and simulated on some functional forms, we find that the case of BOT with regulations performs between the cases of maximizing welfare and that of maximizing profit. From the perspective of the government, regulation has less power in a project with low elastic demand. Furthermore, even when the regulation is strict, a high cost-efficient firm with BOT could result in a higher level of social welfare than that without a BOT scheme.  相似文献   

3.
两步分级法在公路隧道动态施工围岩分级中的应用   总被引:1,自引:0,他引:1  
《JTG D70-2004公路隧道设计规范》中定性与定量[BQ]值相结合的两步分级法从定性和定量两个角度出发,互相校验和检验,采用多因素指标进行评判,对影响围岩稳定性的分析较为全面,该方法在安徽六潜高速公路隧道中应用效果较好,为调整优化相应工程措施提供了重要依据。  相似文献   

4.
Strategies used to deploy technological innovations are central determinants of the degree to which those innovations realize their potential effect on social and economic productivity. The U.S. Interstate highway system was a deployment mechanism for the design innovations of high-speed geometric design and the control of highway access. This strategy was defined by rigid uniform minimum standards of facility design, severely constrained alternatives for configuring the network of facilities, and an inflexible and, in some cases, inappropriate institutional structure for constructing facilities. This strategy compromised the realization of productivity improvements available through the deployment of these innovations. This paper explores the origins of this deployment strategy and generalizes to a discussion of deployment strategies for large engineered systems. It shows that each of the Interstate program's provisions derived from traditions of the agency charged with implementing it and from political expedients embraced to enact the program.  相似文献   

5.
分析了影响公路施工项目进度的因素,介绍进度计划的制定和实施,提出工程进度的控制措施。  相似文献   

6.
针对道路不同的病害,结合省道215公路大修施工,采取了相应不同的维修方案,使道路恢复到原来的使用状态。  相似文献   

7.
我国传统交通运输体系是以铁路为主,公路、水运、空运为辅.国民经济的发展和运输需求的变化使这种运输结构呈现很大的不适应性.  相似文献   

8.
公路养护小修保养预算中路面破损率的整理过程   总被引:1,自引:0,他引:1  
公路养护小修保养预算(简称小保测算)是公路养护工作的重要组成部分,小保测算涉及指标较多,其中路面破损率是主要指标之一,需要进行路面病害调查、统计、整理计算才能求得,进而求得小保费用。从最原始的数据采集说起,详细论述小保测算中路面破损率的求算过程。  相似文献   

9.
介绍了旧沥青路面冷再生技术的现场施工流程和施工质量控制。  相似文献   

10.
结合日东高速公路收费管理工作的实践,总结出治理倒卡、闯关、假冒军车等逃费现象的方法和措施。  相似文献   

11.
Environmental justice (EJ) assessment has traditionally focused on identifying distributive effects to protected populations. Federal and State highway improvement programs have been established to stimulate economic development for these populations. While this issue has long been recognized as part of EJ initiatives, no quantitative comparisons of highway construction impacts on protected populations have been reported in the literature. This paper presents a dynamic modeling approach to investigate impacts to protected and low-Income populations in highway planning using an integrated Geographic Information System (GIS) and Genetic Algorithms (GAs) optimization framework. Using census and county level parcel data, the model integrates various socioeconomic factors into a GIS while generating highway alignments using GAs. Examples using county level census data from North Carolina are demonstrated to test the sensitivity of generated highway alignments with constrained distances from protected populations. The results indicate that it is important to consider local social and economic effects, in addition to regional planning objectives when measuring the effectiveness of feasibility studies associated with highway construction. Within the proposed modeling framework attention is directed on various EJ initiatives, such as environmental health and safety laws in minority and low-income areas. The model would help planners, designers, and policy-makers understand the intricate interrelationships among local communities, while facilitating more scientific and economically equitable planning for highway construction projects.  相似文献   

12.
Transport planning is based on traffic forecasts which are subject to great uncertainties. These uncertainties have generally been ignored or, at least, not explicitly included in the planning process. This paper describes the principles behind the estimation of the uncertainty (or range of error) of the forecasts of a traffic model and discusses the means by which this information can be absorbed into the decision-making in transport planning projects. These principles have been applied to the appraisal of a British highway project and throughout the paper reference is made to this project in order to illustrate the results of the practical application of an explicit treatment of uncertainty. It is believed that this approach can and should be developed for application in most areas of transport planning, leading inevitably to an improvement in the quality of the decisions taken.  相似文献   

13.
冷再生技术是一种新的施工工艺,其原理是将原路面及基层破碎后作为集料,再辅以水泥、沥青、石灰等稳定剂和一定数量的集料,经拌和、整平、碾压等工艺,重新处理后而形成新的路面基层,从而可使原路面功能得以恢复。  相似文献   

14.
利用山东省干线公路2008至2011年交通量数据,分析了境内国、省道路交通流量发展状况。结果表明近年来山东省路网平均交通量持续增长,路网拥挤度有所上升。最后,根据分析结果,给出了山东省干线公路未来发展建议。  相似文献   

15.
Taxis make an important contribution to transport in many parts of the world, offering demand‐responsive, door‐to‐door transport. In larger cities, taxis may be hailed on‐street or taken from taxi ranks. Elsewhere, taxis are usually ordered by phone. The objective of a taxi dispatcher is to maximize the efficiency of fleet utilization. While the spatial and temporal distribution of taxi requests has in general a high degree of predictability, real time traffic congestion information can be collected and disseminated to taxis by communication technologies. The efficiency of taxi dispatching may be significantly improved through the anticipation of future requests and traffic conditions. A rolling horizon approach to the optimisation of taxi dispatching is formulated, which takes the stochastic and dynamic nature of the problem into account. Numerical experiments are presented to illustrate the performances of the heuristics, taking the time dependency of travel times and passenger arrivals into account.  相似文献   

16.
The effects of highway development on housing prices   总被引:1,自引:0,他引:1  
The purpose of this research is to estimate the effects of highway development projects on the price of housing. Transportation development projects, highways in particular, improve a certain area’s accessibility but also increase its levels of exposure to traffic intensity and noise pollution. These externalities are evaluated by homeowners and residents and are reflected in the price of housing. In this paper, we use several repeat sales model specifications, including difference-in-differences estimators, and control for neighborhood effects to examine housing price trends in the municipalities around two newly developed highways in the Netherlands. The results of the research demonstrate that changes in accessibility result in a significant positive effect on the price of housing in nearby municipalities, but that increased noise pollution and traffic intensity levels result in a decrease in prices. The findings also confirm that combining the total effects of all externalities, the effect of highway development on the price of housing is generally positive, and this effect is salient even before the project is completed due to public anticipation effects.  相似文献   

17.
运用公共管理学和公共经济学等学科知识分析农村公路的公共产品属性,指出传统单一的融资方式已经不能适应今后农村公路发展的需要,分析了农村公路的供给主体及多元化筹资的必然性。  相似文献   

18.
设备众多、专业性强,施工界面交叉多,工程量大且工期短,是高速公路机电工程的特点。为保证机电工程质量、进度、费用、环保、资料等方面符合合同及规范要求,探讨了高速公路机电工程监理的重点难点,并提出监理工作程序及监理控制要点。  相似文献   

19.
通过使用连续介质快速拉格朗日差分法(Fast Lagrangian Analysis of Continua,简写FLAC)对粉土路基于粘土路基的稳定性进行分析。并对路基高度、地基种类及边坡形式等对路基稳定性产生影响的因素进行分析研究,得出以下规律:路基边坡安全系数随路基高度增大而减小,但此变化存在一临界高度,在此临界高度附近,安全系数以不同的速度减小。如将粉土地基表层30 cm的压实度由85%提高到90%,安全系数将有很大的提高;但由90%提高到93%,则安全系数变化不大。对于10~20 m高度的路基,边坡形式(即一坡式与台阶式)对路基的稳定性影响很小,后者比前者对应的安全系数稍大。  相似文献   

20.
物流过程的全程可见性一直是物流信息技术应用的核心问题.而对于广博、复杂的中国版图,实现公路运输途中的全程跟踪一直是所有物流企业、货主的梦想.  相似文献   

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