全文获取类型
收费全文 | 376篇 |
免费 | 11篇 |
专业分类
公路运输 | 36篇 |
综合类 | 164篇 |
水路运输 | 35篇 |
铁路运输 | 27篇 |
综合运输 | 125篇 |
出版年
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 5篇 |
2020年 | 10篇 |
2019年 | 8篇 |
2018年 | 25篇 |
2017年 | 14篇 |
2016年 | 20篇 |
2015年 | 33篇 |
2014年 | 37篇 |
2013年 | 22篇 |
2012年 | 20篇 |
2011年 | 30篇 |
2010年 | 29篇 |
2009年 | 14篇 |
2008年 | 21篇 |
2007年 | 15篇 |
2006年 | 17篇 |
2005年 | 11篇 |
2004年 | 11篇 |
2003年 | 8篇 |
2002年 | 5篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1989年 | 1篇 |
1988年 | 1篇 |
排序方式: 共有387条查询结果,搜索用时 312 毫秒
101.
基于种群演变和共生理论,采用Cobb-Douglas生产函数描述航运市场整体需求,从顾客的购买行为出发,以收益最大作为集装箱班轮公司的经营目标,以基于时间序列的运力与运价作为决策变量,构建了集装箱班轮公司航次运力销售过程优化模型。运用Taylor公式与最小二乘法等代数变换手段将非线性规划问题转化为线性规划问题,对关键参数进行了标定与敏感性分析,并利用MATLAB软件进行仿真验证。仿真结果表明:当单个集装箱班轮公司的运力为104 TEU时,采用常规的销售策略,集装箱班轮公司可售出的运力为7 534~9 966TEU,获得收益为1 233 158~12 915 936USD,采用提出的优化模型,可售出的运力为9 915TEU,获得收益为15 111 975USD,收益至少提高17%;当2个集装箱班轮公司的运力均为104 TEU时,采用提出的优化模型,2个集装箱班轮公司可售出的运力分别为9 920、9 947TEU,获得收益分别为14 241 771、9 737 528USD,达到纳什均衡;当3个集装箱班轮公司的运力均为104 TEU时,采用提出的优化模型,3个集装箱班轮公司可售出的运力分别为8 289、5 526、6 034TEU,获得收益分别为6 755 755、6 119 906、4 377 758USD,达到纳什均衡。可见提出的模型可描述多个集装箱班轮公司运力销售情况,且表现出显著的优化效果。 相似文献
102.
精确的物流成本信息是准确制定物流服务价格的关键要素.然而,传统成本核算方法扭曲了成本信息,难于适应物流企业对物流服务成本核算与定价要求.本文引入先进作业成本法(Activity Based Costing,简称ABC),探讨了作业成本法在物流项目成本核算与定价中的基本原理,针对物流项目的运作模式、流程和特点构建了基于作... 相似文献
103.
回顾了20世纪60年代以来美国联邦层面制定的一系列缓解交通拥堵的法律、法案和规章.总结各个阶段相关法律、法案和规章产生的背景、效力及特征:20世纪60-70年代,利用公路交通工程技术解决城市交通问题;20世纪70-80年代,增加公共交通资金的投入;20世纪80-90年代,引入绩效评估体系以及非政府组织参与治堵行动;20... 相似文献
104.
考虑尾气排放的道路收费是将道路使用外部性内部化的重要手段,有利于减少环境污染、实现社会效益的最大化.介绍了过去30年里相关理论的经济学基础、产生背景以及发展情况,指出由于相关技术和出行者认识有限,具体实施还存在一定难度.综述了尾气排放量的测算方法、收费模型建立以及收费对汽车尾气排放的影响评估,分析了其优缺点和适用范围.... 相似文献
105.
106.
Quantifying the benefit of responsive pricing and travel information in the stochastic congestion pricing problem 总被引:1,自引:0,他引:1
Lauren M. Gardner Stephen D. Boyles 《Transportation Research Part A: Policy and Practice》2011,45(3):204-218
This paper is concerned with roadway pricing amidst the uncertainty which characterizes long-term transportation planning. Uncertainty is considered both on the supply-side (e.g., the effect of incidents on habitual route choice behavior) and on the demand-side (e.g., due to prediction errors in demand forecasting). The framework developed in this paper also allows the benefits of real-time travel information to be compared directly against the benefits of responsive pricing, allowing planning agencies to identify the value of these policy options or contract terms in publicly-operated toll roads. Specifically, six scenarios reflect different combinations of policy options, and correspond to different solution methods for optimal tolls. Demonstrations are provided on both the Sioux falls and Anaheim networks. Results indicate that providing information to drivers implemented alongside responsive tolling may reduce expected total system travel time by over 9%, though more than 8% of the improvement is due to providing information, with the remaining 1% improvement gained from responsive tolling. 相似文献
107.
Spitsmijden, peak avoidance in Dutch, is the largest systematic effort to date to study, in the field, the potential of rewards as a policy mean for changing commuter behavior. A 13 week field study was organized in The Netherlands with the purpose of longitudinally investigating the impacts of rewards on commuter behavior. Different levels and types of rewards were applied and behavior was tracked with state-of-the art detection equipment. Based on the collected data, which included also pre and post-test measurements, a mixed discrete choice model was estimated. The results suggest that rewards can be effective tools in changing commuting behavior. Specifically rewards reduce the shares of rush-hour driving, shift driving to off-peak times and increase the shares of public transport, cycling and working from home. Mediating factors include socio-demographic characteristics, scheduling constraints and work time flexibility, habitual behavior, attitudes to commuting alternatives, the availability of travel information and even the weather. The success of this study has encouraged adoption of rewards, as additional policy tools, to alleviate congestion, especially during temporary road closures. 相似文献
108.
Kara M. Kockelman Jason D. Lemp 《Transportation Research Part A: Policy and Practice》2011,45(8):825-838
Pricing of roadways opens doors for infrastructure financing, and congestion pricing seeks to address inefficiencies in roadway operations. This paper emphasizes the revenue-generation opportunities and welfare impacts of flat-tolling schemes, standard congestion pricing, and credit-based congestion pricing policies. While most roadway investment decisions focus on travel time savings for existing trips, this work turns to logsum differences (which quantify changes in consumer surplus) for nested logit specifications across two traveler types, two destinations, three modes and three times of day, in order to arrive at welfare- and revenue-maximizing solutions. This behavioral specification is quite flexible, and facilitates benefit-cost calculations (as well as equity analysis), as demonstrated in this paper.The various cases examined suggest significant opportunities for financing new roadway investment while addressing congestion and equity issues, with net gains for both traveler types. Application results illustrate how, even after roadway construction and maintenance costs are covered, receipts may remain to distribute to eligible travelers so that typical travelers can be made better off than if a new, non-tolled road had been constructed. Moreover, tolling both routes (new and old) results in substantially shorter payback periods (5 versus 20 years) and higher welfare outcomes (in the case of welfare-maximizing tolls with credit distributions to all travelers). The tools and techniques highlighted here illustrate practical methods for identifying welfare-enhancing and cost-recovering investment opportunities, while recognizing multiple user classes and appropriate demand elasticity across times of day, destinations, modes and routes. 相似文献
109.
We estimate the effect of a road pricing policy introduced in Milan in 2008 on concentrations of benzene, carbon monoxide, particulates, nitrogen dioxide and sulphur dioxide. We found a sizeable effect of the Ecopass on air quality in terms of reduction in the concentration of carbon monoxide and particulates a few days after its introduction, although this effect disappeared after only one week. We interpret these results as indicative of an inefficient policy design: motorbikes were not charged and the treated area is too limited to generate positive outcomes for the whole city. Further evidence from a natural experiment given by a temporary suspension of the charge in 2012 confirms our hypothesis on the incentives for motorbike usage. 相似文献
110.
为科学管理共享停车资源,构建一种共享停车泊位的分配-定价-收益分配机制。首先,以存在多个地块的区域为对象,根据出行者对不同地块及停车时间模式的选择偏好构建停车许可证的最优分配-定价模型,其中,最优分配模型为组合拍卖竞胜标确定问题(NP困难问题)。其次,利用Benders分解原理、对偶理论及新型升价拍卖代理系统构建调优法对停车许可证进行拍卖。最后,为调动共享泊位提供者的积极性,利用沙普利值法构建基于对社会福利贡献程度的停车收益分配模型。由理论分析及数值试验可知,运用上述机制可精确实现社会福利最优状态,最小竞争均衡价格与公平的收益分配。结果表明:①相较VCG机制与Leonard机制,调优法不仅可精确求解停车许可证的最优分配-定价,而且在算法最坏时间复杂度方面拥有更高效率;②在调优法的每个步骤中,即使停车许可证的分配并非最优,通过机制所实现的收费定价依然具有防止策略性操作的重要性质;③调优法可在较少的步骤之内实现较高的社会福利;④新型升价拍卖代理系统拥有多项式型的最坏时间复杂度;⑤通过最优分配-定价机制可获得每位出行者的选择偏好,进而可计算不同泊位提供者组合条件下的社会福利,实现沙普利值法在现实应用中的可计算性。 相似文献