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461.
为解决干线公交速度引导存在多要素关联约束强,全局效果差的问题,本文提出基于分级多目标决策的干线公交速度引导模型。基于公交线路运行特性的全局优化指标优势分析,设计以公交线路综合准点率为主,交叉口停车次数和分段引导速度均衡为辅的线路全局优化目标体系,并考虑多目标间的关联约束和优先控制差异,构建基于拉格朗日乘子法和遗传算法分层组合的干线公交速度引导分级多目标递阶决策模型;最后,通过实际场景测试,验证模型的有效性。测试结果表明:模型能够克服非全局指标优化的局部最优问题,将全线路各班次综合准点率和交叉口停车次数由非全局指标的69.67%和2.37次 ⋅ 班-1 提升到90.53%和1.23次 ⋅ 班-1;并且综合准点率比全局多目标加权方法提升8.65%,能够较好保障综合准点率目标的优先性,有效提升干线公交的通行效率和服务可靠性。 相似文献
462.
In the absence of system control strategies, it is common to observe bus bunching in transit operations. A transit operator would benefit from an accurate forecast of bus operations in order to control the system before it becomes too disrupted to be restored to a stable condition. To accomplish this, we present a general bus prediction framework. This framework relies on a stochastic and event-based bus operation model that provides sets of possible bus trajectories based on the observation of current bus positions, available via global positioning system (GPS) data. The median of the set of possible trajectories, called a particle, is used as the prediction. In particular, this enables the anticipation of irregularities between buses. Several bus models are proposed depending on the dwell and inter-stop running time representations. These models are calibrated and applied to a real case study thanks to the high quality data provided by TriMet (the Portland, Oregon, USA transit district). Predictions are finally evaluated by an a posteriori comparison with the real trajectories. The results highlight that only bus models accounting for the bus load can provide valid forecasts of a bus route over a large prediction horizon, especially for headway variations. Accounting for traffic signal timings and actual traffic flows does not significantly improves the prediction. Such a framework paves the way for further development of refined dynamic control strategies for bus operations. 相似文献
463.
建设快速公交系统的核心要素是道路资源的优先使用,即道路优先通行权.只有为快速公交提供道路优先通行权,才能发挥其快速、便捷、集中的优势,体现其价值.本文为道路优先通行权制度的构建提出了相应的保障措施. 相似文献
464.
建设公交都市已成为大都市缓解城市交通拥堵的发展方向。本文在公交都市建设实践及研究成果的基础上,分析了常规公交在公交都市中的地位及公交企业的使命,提出了公交企业在公交都市建设中的任务体系,对公交企业的经营管理有一定的指导作用。 相似文献
465.
H. McGeehan 《运输规划与技术》2013,36(3-4):221-229
The primary aim of the paper is to determine a short‐run cost function for Dublin City Bus Services (DCS), using a translog approach. The results show that there are significant economies of density in the transit operation. The results also indicate that the structure of DCS is characterised by a homothetic production function and that partial elasticities of substitution are non‐unitary. 相似文献
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Exclusive bus lanes provide a very high level of priority for transit operations, especially for Bus Rapid Transit and Express service, but these lanes could be underutilized and be a source of extra capacity if they could be shared in an intelligent way. This article explores the benefits of providing intermittent priority, called bus lane with intermittent and dynamic priority, of these exclusive bus lanes. Intermittent and dynamic priority can be implemented by allowing vehicles to use the lane when Bus Rapid Transit or Express bus is not present. Drivers can be alerted when a bus is in the lane using either infrastructure-based signs, or in the future using infrastructure-to-vehicle, or connected vehicle communications. Some critical operating parameters for implementing bus lane with intermittent and dynamic priority system including clear distance, degree of saturation (volume-to-capacity ratio), connected vehicle penetration, and bus departure/headway frequency have been investigated in this paper. 相似文献
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以非集计离散选择模型理论为依据,建立基于Logit的城际旅客交通方式选择行为模型.根据武汉周边4个城市(孝感、随州、襄阳和十堰)经武汉到上海的旅客出行方式意向选择(Stated Preference,SP)调查数据,研究了影响旅客选择"空巴联运"(即航空与巴士接驳)方式的重要因素,并对影响因素进行灵敏度分析,估计3种交通方式("空巴联运"、动车—高铁、大巴—高铁)的客流分担率.基于调查数据,对模型参数进行了标定.结果表明,城市内出行时间(程前程后出行时间)和总出行货币费用对旅客出行方式选择影响显著. 相似文献