全文获取类型
收费全文 | 439篇 |
免费 | 20篇 |
专业分类
公路运输 | 97篇 |
综合类 | 240篇 |
水路运输 | 14篇 |
铁路运输 | 12篇 |
综合运输 | 96篇 |
出版年
2024年 | 4篇 |
2023年 | 2篇 |
2022年 | 8篇 |
2021年 | 17篇 |
2020年 | 10篇 |
2019年 | 11篇 |
2018年 | 10篇 |
2017年 | 20篇 |
2016年 | 20篇 |
2015年 | 25篇 |
2014年 | 45篇 |
2013年 | 38篇 |
2012年 | 35篇 |
2011年 | 44篇 |
2010年 | 21篇 |
2009年 | 34篇 |
2008年 | 17篇 |
2007年 | 29篇 |
2006年 | 24篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1995年 | 3篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 2篇 |
排序方式: 共有459条查询结果,搜索用时 31 毫秒
31.
文中从观音桥的区位、发展现状、交通问题等方面进行了深入的分析与研究,找出现状商圈交通存在的问题及根本原因,然后针对问题和商圈未来发展需求,从路网、轨道、公交、停车、步行五个方面提出了交通拥堵改善的思路、措施与对策. 相似文献
32.
通过对交通拥堵进行反思,认为交通拥堵是充满活力的成功城市的伴生品,应从不同角度考虑拥堵问题.提出了十项有别于传统观点的提议,主要包括:机动性至关重要,交通拥堵是社会、经济活力的象征;道路扩容效果短暂,并会诱发潜在需求,但仍可带来一定的社会、经济效益;土地使用对出行行为的改变需要长期的努力;紧凑型发展会加剧交通拥堵;降低... 相似文献
33.
34.
针对混合交通流中智能网联车辆(Connected and Autonomous Vehicles, CAVs)和人工驾驶车辆的交织干涉问题,本文在传统交通流统计理论模型和一阶连续介质模型的基础上,通过引入智能驾驶员跟驰模型(Intelligent driver model, IDM)和协同自适应巡航控制模型(Cooperative
Adaptive Cruise Control, CACC),构建人工驾驶车辆和CAVs的混合交通流偶发拥堵演化模型,探索CAVs混入和诱导干涉措施对混合交通流偶发性拥堵传播规律的影响。实验选取重庆市华陶立交至巴南立交路段为路网原型,对CAVs不同渗透率( Pc )下的路段拥堵演化情况进行仿真。实验结果表明:CAVs渗透率越高,混合流流量、占有率和速度的改善情况越显著,但只有当 Pc ≥ 0.2
时,网联车辆对拥堵消散的改善效果才较为明显;Pc ≤ 0.8 时,干涉措施下,拥堵消散状态的持续时间约为不采用干涉措施的 50%;当 Pc = 1.0 时,网联车辆的通行能力是纯人工驾驶交通流的2.34倍;分别在非干涉措施和干涉措施下计算拥堵评价指标,与仿真结果进行对比,最大相对误差在5.38%之内,验证了模型的准确性。研究成果对疏散交通拥堵具有重要意义。 相似文献
35.
Airport demand management aims to mitigate air traffic congestion by limiting the imbalances between demand and capacity at busy airports through administrative measures (e.g., slot controls) or economic incentives (e.g., congestion pricing, slot auctions). This paper provides an integrated synthesis of the contributions of the fields of operations research/management science (OR/MS) and economics on the subject matter. From an operating standpoint, assessing the benefits of demand management requires estimates of airport capacity and models of airport on-time performance. From a managerial standpoint, the design of demand management mechanisms can be supported by decision-making models of flight scheduling. From an economic standpoint, the welfare impact of congestion pricing, slot controls and slot auctions depends on the market structure at the airport. This paper proposes an integrated framework that underscores the interdependencies between these operating, managerial and economic aspects to foster cross-disciplinary approaches toward more effective demand management policies at busy airports worldwide. 相似文献
36.
交通拥堵收费是解决道路拥堵问题的有效措施。假设使用小汽车到达拥挤收费区域边界的出行者可通过2种方式到达拥挤收费中心区:小汽车直达及停车换乘公共交通(P&R)。对于出行者甲(对小汽车出行需求偏刚性)、乙(对小汽车出行需求偏弹性),采用进化博弈的方法,建立效益矩阵,分析在不同政府定价条件下两者出行方式选择行为的演化模型。结果表明,政府交通拥堵收费对出行者出行方式选择行为的演化起着重要作用,不同的定价区间会使得出行方式向不同的稳定状态演变。分析各种定价区间下出行者出行方式选择行为。 相似文献
37.
In this paper, we study the effectiveness of accident messages that are displayed on freeway changeable message signs (CMS). Motivated by the lack of empirical studies and the mixed results reported in the limited empirical studies, this paper focuses on the comparison of different aggregate analysis methodologies and their corresponding results, using the same empirical data set. We have two major findings. First, we find that the CMS accident messages do not seem to have any significant immediate effect on driver diversion based on our empirical data. Visible congestion, on the other hand, seems to be an important factor for driver diversion. Second, we show how the conclusion could have been if wrong methodologies were to be adopted. Methods that rely on correlation alone but not the timing of events (what we call correlation method) yield high correlation between CMS accident messages and driver diversion, which is typically and incorrectly interpreted as CMS accident messages being effective. 相似文献
38.
The health cost of on-road air pollution exposure is a component of traffic marginal costs that has not previously been assessed. The main objective of this paper is to introduce on-road pollution exposure as an externality of traffic, particularly important during traffic congestion when on-road pollution exposure is highest. Marginal private and external cost equations are developed that include on-road pollution exposure in addition to time, fuel, and pollution emissions components. The marginal external cost of on-road exposure includes terms for the marginal vehicle’s emissions, the increased emissions from all vehicles caused by additional congestion from the marginal vehicle, and the additional exposure duration for all travelers caused by additional congestion from the marginal vehicle. A sensitivity analysis shows that on-road pollution exposure can be a large portion (18%) of marginal social costs of traffic flow near freeway capacity, ranging from 4% to 38% with different exposure parameters. In an optimal pricing scenario, excluding the on-road exposure externality can lead to 6% residual welfare loss because of sub-optimal tolls. While regional pollution generates greater costs in uncongested conditions, on-road exposure comes to dominate health costs on congested freeways because of increased duration and intensity of exposure. The estimated marginal cost and benefit curves indicate a theoretical preference for price controls to address the externality problem. The inclusion of on-road exposure costs reduces the magnitudes of projects required to cover implementation costs for intelligent transportation system (ITS) improvements; the net benefits of road-pricing ITS systems are increased more than the net benefits of ITS traffic flow improvements. When considering distinct vehicle classes, inclusion of on-road exposure costs greatly increases heavy-duty vehicle marginal costs because of their higher emissions rates and greater roadway capacity utilization. Lastly, there are large uncertainties associated with the parameters utilized in the estimation of health outcomes that are a function of travel pollution intensity and duration. More research is needed to develop on-road exposure modeling tools that link repeated short-duration exposure and health outcomes. 相似文献
39.
40.
Using the revenues from congestion pricing 总被引:6,自引:0,他引:6
Kenneth A. Small 《Transportation》1992,19(4):359-381
The economic theory behind congestion pricing relies on using the revenues to help compensate highway users. But can practical methods of using revenues come close to achieving this compensation, and still have salient appeal to important political groups? This paper investigates the possibilities for designing a package of revenue uses that can achieve these twin goals. The suggested approach returns two-thirds of the revenues to travelers through travel allowances and tax reductions, and uses the rest to improve transportation throughout the area, including affected business centers. By replacing regressive sales and fuel taxes, this approach offsets the tendency of the prices alone to have a regressive distributional impact. By lowering taxes, funding new highways, improving transit, and upgrading business centers, the package provides inducements for support from several key interest groups. The potential amounts of money involved are discussed using nationwide data, and in more detail using a case study of ubiquitous facility pricing throughout the Los Angeles region. Illustrative calculations of the effects on various individuals confirm that such a package can create net benefits for a wide spectrum of people and interest groups. 相似文献