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81.
This contribution furthers the control framework for driver assistance systems in Part I to cooperative systems, where equipped vehicles can exchange relevant information via vehicle-to-vehicle communication to improve the awareness of the ambient situation (cooperative sensing) and to manoeuvre together under a common goal (cooperative control). To operationalize the cooperative sensing strategy, the framework is applied to the development of a multi-anticipative controller, where an equipped vehicle uses information from its direct predecessor to predict the behaviour of its pre-predecessor. To operationalize the cooperative control strategy, we design cooperative controllers for sequential equipped vehicles in a platoon, where they collaborate to optimise a joint objective. The cooperative control strategy is not restricted to cooperation between equipped vehicles. When followed by a human-driven vehicle, equipped vehicles can still exhibit cooperative behaviour by predicting the behaviour of the human-driven follower, even if the prediction is not perfect.The performance of the proposed controllers are assessed by simulating a platoon of 11 vehicles with reference to the non-cooperative controller proposed in Part I. Evaluations show that the multi-anticipative controller generates smoother behaviour in accelerating phase. By a careful choice of the running cost specification, cooperative controllers lead to smoother decelerating behaviour and more responsive and agile accelerating behaviour compared to the non-cooperative controller. The dynamic characteristics of the proposed controllers provide new insights into the potential impact of cooperative systems on traffic flow operations, particularly at the congestion head and tail.  相似文献   
82.
GLENN LYONS 《运输评论》2013,33(4):485-509
In 1963, the Buchanan Report in the UK advocated a combination of new road capacity, improved public transport and traffic restraint as a means to tackle congestion. Forty years on, and the advice from many transport experts remains the same. However, the scale and complexity of the problems associated with a mobility‐dependent society have grown. The need for politicians to make tough but realistic policy decisions on transport is now becoming unavoidable. They must confront the realities of living with the car as must the general public. Policymakers now also have social well‐being and sustainable development moving higher on their agendas alongside transport. Against such a backdrop, the paper makes the case for transport research, policy and practice to acknowledge more fully the inherent links between transport and society. It argues that greater recognition and understanding of such links is crucial to confronting the present realities. Transport does not merely serve society: it shapes society, as in turn society shapes transport. The future of each is dependent on the other, and this fact must be recognized. The paper advocates in turn that the transport profession must move from its heartlands in engineering and economics also to embrace more fully such disciplines as sociology and psychology. A factual picture of the many facets of present‐day society is presented and the implications for travel demand are discussed. Through considering phenomena such as social norms and habitual behaviour, it is then argued that the travel choices and behaviour of individuals are not simply a matter of economic optimization. This points to the need for decision‐makers to be furnished with better evidence about the transport problems faced and the potential efficacy of measures that might be taken. Discussion of public attitudes and the role of the media are included in the context of assessing how politicians can be encouraged and supported in their implementation of realistic but unpopular policies. Evidence and experience within the paper are UK based, although many of the issues and arguments apply world wide.  相似文献   
83.
84.
该控制箱具有点动、连续动作、远程遥控控制功能。点动功能实现转辙机动作杆单次推出、拉入;连续动作功能实现转辙机按照设定的时间重复(推出→停止→拉入→停止)动作;远程遥控控制功能,抗干扰能力强,操作使用方便。可以满足道岔施工、电动转辙机试验需要。  相似文献   
85.
长大隧道施工地质超前预测预报技术应用研究   总被引:7,自引:0,他引:7  
结合渝怀铁路金洞隧道施工地质超前预测预报技术的实施,着重介绍长大隧道施工地质超前预测预报技术应用研究的目的、思路、方法、手段、工作原理、实施步骤与判别方法、主要预测预报成果及体会。  相似文献   
86.
铁路工程地质钻探用钻机结构性能几十年未变,已远远不能适应目前钻掘工程和岩土工程的市场要求,通过对国内外钻机生产现状的分析,探讨铁路钻探设备的发展方向。  相似文献   
87.
为满足人们对汽车更加智能化,人性化的需求,基于全球定位系统(GPS),人工智能技术以及智能手机控制技术等实现汽车的远程智能控制。文章将从国内外汽车智能控制发展现状,汽车远程智能控制如何实现,需要运用的技术点出发进行阐述,如何实现对汽车远程智能控制,以及实现汽车远程智能化控制后带来的便利进行描述。文章主要从汽车如何实现远程智能控制相关技术问题,以及其优缺点和未来发展前景。充分展现人工智能时代带来的便利,促进汽车自动驾驶的时代的到来。  相似文献   
88.
浙江苍岭隧道左线凝灰岩突水现象工程地质特征研究   总被引:1,自引:0,他引:1  
研究目的:对发生在浙江苍岭隧道施工中发生在凝灰岩中的突水事故的成因、特点和主要控制因素进行研究,以便更好地对其进行预测和防治。研究方法:根据发生突水事故的浙江苍岭隧道的现场地质观测资料,具体分析其形成的规模、位置、诱发因素以及地质条件,从地质工程的角度,对突水发生地段隧道的岩石组成、地质构造、现代构造应力场以及地下水等工程地质特征进行探讨,进而发现其规律和防治预测的特点。研究结果:苍岭隧道施工中发生的突水事故受到地质构造和地下水活动特点的强烈控制,虽然凝灰岩本身不溶于水,但在现代构造应力场的作用下形成的特殊的构造,为地下水的运移和赋存提供了通道和场所,是造成突水的主要原因。并在此基础上,借助TSP-203^+地质超前预报预报系统,建立了苍岭隧道突水灾害的超前预报识别标志,提出了“先疏导排水、后注浆封闭”的突水防治措施。研究结论:对于隧道出现的土水灾害,首先要进行其工程地质的研究,在此基础上再进行准确的预测和合理的防治是有效防治隧道灾害的正确方法和步骤。  相似文献   
89.
张明华 《中南公路工程》2005,30(3):43-47,85
运用遥感及地理信息技术能有效地从图像光谱特征、空间特征、影像纹理、微地貌、景观等诸多方面,对岩石、构造、地形地貌、地质灾害等进行识别与划分,从遥感影像中提取公路工程地质信息.结合ENVI和ARC/INFO软件进行数据采集和专题制图,利用GIS的空间分析功能,能快速、准确地对公路工程地质条件进行定量分析和综合评价.  相似文献   
90.
利用可见光和近红外波段的地物光谱反射率差异可以从遥感数据中提取水体。利用归一化植被指数(NDVI)从2个MODIS空间分辨率为250m的遥感数据中提取水体,并进行假彩色合成,实现遥感数据水体制图。  相似文献   
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