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961.
Estimation of the determinants of bicycle mode share for the journey to work using census data 总被引:1,自引:0,他引:1
A model is presented that relates the proportion of bicycle journeys to work for English and Welsh electoral wards to relevant
socio-economic, transport and physical variables. A number of previous studies have exploited existing disaggregate data sets.
This study uses UK 2001 census data, is based on a logistic regression model and provides complementary evidence based on
aggregate data for the determinants of cycle choice. It suggests a saturation level for bicycle use of 43%. Smaller proportions
cycle in wards with more females and higher car ownership. The physical condition of the highway, rainfall and temperature
each have an effect on the proportion that cycles to work, but the most significant physical variable is hilliness. The proportion
of bicycle route that is off-road is shown to be significant, although it displays a low elasticity (+0.049) and this contrasts
with more significant changes usually forecast by models constructed from stated preference based data. Forecasting shows
the trend in car ownership has a significant effect on cycle use and offsets the positive effect of the provision of off-road
routes for cycle traffic but only in districts that are moderately hilly or hilly. The provision of infrastructure alone appears
insufficient to engender higher levels of cycling.
John Parkin joined academia after a career in consultancy. He has experience of all stages of the promotion of transport infrastructure, from planning and modelling to design and implementation. His specialises in transport engineering with an emphasis on design innovation, sustainability principles and community benefit. Mark Wardman has been involved in transport research for over 20 years. His main research interests are in behavioural response models in general and stated preference in particular. Areas of application have included public transport, notably rail, with several novel applications to cycling and environmental issues. Matthew Page research interests include transport policy and how it has developed, the environmental impacts of transport, the impacts of transport on climate change, and walking and cycling. 相似文献
Matthew PageEmail: |
John Parkin joined academia after a career in consultancy. He has experience of all stages of the promotion of transport infrastructure, from planning and modelling to design and implementation. His specialises in transport engineering with an emphasis on design innovation, sustainability principles and community benefit. Mark Wardman has been involved in transport research for over 20 years. His main research interests are in behavioural response models in general and stated preference in particular. Areas of application have included public transport, notably rail, with several novel applications to cycling and environmental issues. Matthew Page research interests include transport policy and how it has developed, the environmental impacts of transport, the impacts of transport on climate change, and walking and cycling. 相似文献
962.
利用随机森林算法,通过组合多棵基于随机向量的决策树对电力系统的暂态稳定性分类,提出了一种暂态稳定评估模型.在IEEE 16机和IEEE 50机测试系统进行的仿真验证了该模型对暂态稳定评估的有效性,其评估性能较经典决策树算法、人工神经网络、支持向量机和K最近邻方法均有提高. 相似文献
963.
目的探讨胃癌肝转移与多种危险因素之间的关系。方法收集376例胃癌病例资料,选取12项指标作为胃癌肝转移的危险因素,采用Logistic回归方法,进行单因素和多因素分析。结果单因素和多因素分析结果显示胃癌的组织学类型、淋巴结转移和临床病理分期与肝转移有关。单因素分析还显示浸润深度也是与之有关的因素,而其他因素与肝转移无关。结论胃癌发生肝转移与肿瘤的组织学类型、浸润深度、淋巴结转移和临床病理分期有关。 相似文献
964.
965.
Parallel Key-insulated Signature: Framework and Construction 总被引:1,自引:0,他引:1
To deal with the key-exposure problem in signature systems, a new framework named parallel key-insulated signature (PKIS) was introduced, and a concrete PKIS scheme was proposed. Compared with traditional key-insulated signature (KIS) schemes, the proposed PKIS scheme allows a frequent updating for temporary secret keys without increasing the risk of helper key-exposure. Moreover, the proposed PKIS scheme does not collapse even if some (not all) of the helper keys and some of the temporary secret keys are simultaneously exposed. As a result, the security of the PKIS scheme is greatly enhanced, and the damage caused by key-exposure is successfully minimized. 相似文献
966.
改进非参数回归在交通流量预测中的应用 总被引:1,自引:0,他引:1
实时、准确的短时交通流量预测是实现交通控制与诱导的关键。结合模式识别的思想,提出基于模式识别的非参数回归算法,并将之应用于短时交通流量预测,最后用仿真试验检验了方法的有效性,仿真试验结果表明,该方法具有较高的预测精度。 相似文献
967.
在通信系统仿真中,Gauss随机变量是最重要也是最常用到的随机变量。根据Gauss随机变量产生的基本原理,结合中心极限定理、坐标转换和概率分布的基本知识,分析了产生Gauss随机变量的三类方法,即12求和法、Box-Mull-er法和极坐标法,实现了Gauss随机变量的产生,比较了三种方法和直接使用函数产生Gauss随机变量的性能,提出了检验Gauss随机变量的易实现的三个参数-相对集中度、宽度对称度和相对宽度对称度,分析研究得出:12求和法产生的Gauss随机变量相对集中,Box-Muller法的统计特性、对称性等综合性能更优的结论。 相似文献
968.
分组列车与单组列车是我国车流组织的两种形式,二者互有利弊,对其开行适用条件研究具有理论价值和现实意义。根据固定车组重量分组列车集结的动态特性和车组到达的不确定性,将车组的车数和间隔时间都视为随机变量,应用随机过程理论,解析其在编成站和途中换挂站的集结耗费相对于单组列车的节省和额外消耗,以一昼夜所产生的总净节省的数学期望作为其综合效益的度量,给出分组列车合理开行的判别式和更易判定的必要条件。针对模型的特点,应用离散事件系统仿真方法进行模拟。仿真算例表明:判定条件的吻合率为97.36%,必要条件的失真率为4.52%;其综合效益受到车组平均车数和平均间隔时间参数影响且前者灵敏程度更高;适用于车流量较小且车流到达强度之比接近固定车组重量之比情形。 相似文献
969.
970.