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随着城市化进程的加速,城市排水系统的运行面临着越来越大的挑战。传统的排水系统管理模式存在调度决策支撑不足、效率较低等问题,无法满足现代排水系统精细化管理的需求。探索排水系统厂站网一体化调度模式,对于提高排水系统实际运行效率和管理水平具有重要意义。对上海市某片区市政排水系统厂站网一体化调度应用进行研究,搭建厂站网一体化调度平台,集成排水设施基础数据、物联感知监测数据以及水雨情气象数据数据库,以污水管网干线模型为计算引擎,实现排水运行日常监管、一体化调度支持实际应用等功能,为排水系统高效平稳运行提供支撑。 相似文献
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为分析区域物流发展水平时空演化特性,基于2011~2017年黑龙江省12个地级市物流发展数据,在确定区域物流发展水平测度指标的基础上,利用熵值-加权综合评价模型评估区域物流发展水平,利用差异指数测度区域物流发展差异,利用ArcGIS空间分析技术分析区域物流发展水平的时空演化规律.研究结果表明:黑龙江省区域物流发展相对缓... 相似文献
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Grégory Vandenbulcke Claire Dujardin Isabelle Thomas Bas de GeusBart Degraeuwe Romain MeeusenLuc Int Panis 《Transportation Research Part A: Policy and Practice》2011,45(2):118-137
This paper attempts to explain the spatial variation of the use of a bicycle for commuting to work at the level of the 589 municipalities in Belgium. Regression techniques were used and special attention was paid to autocorrelation, heterogeneity and multicollinearity. Spatial lag models were used to correct for the presence of spatial dependence and a disaggregated modelling strategy was adopted for the northern and southern parts of the country. The results show that much of the inter-municipality variation in bicycle use is related to environmental aspects such as the relief, traffic volumes and cycling accidents. Town size, distance travelled and demographic aspects also have some effect. In addition, there are regional differences in the effects of the structural covariates on bicycle use: the impact of variables such as traffic volume and cycling accidents differs substantially between the north and the south of the country. This paper also suggests that high rates of bicycle use in one municipality stimulate cycling in neighbouring municipalities, and hence that a mass effect can be initiated, i.e. more cycle commuting encourages even more commuters in the area to cycle. These findings provide some recommendations for decision-makers wishing to promote a shift from car to bicycle use. 相似文献
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Sashank Musti 《Transportation Research Part A: Policy and Practice》2011,45(8):707-720
In today’s world of volatile fuel prices and climate concerns, there is little study on the relationship between vehicle ownership patterns and attitudes toward vehicle cost (including fuel prices and feebates) and vehicle technologies. This work provides new data on ownership decisions and owner preferences under various scenarios, coupled with calibrated models to microsimulate Austin’s personal-fleet evolution.Opinion survey results suggest that most Austinites (63%, population-corrected share) support a feebate policy to favor more fuel efficient vehicles. Top purchase criteria are price, type/class, and fuel economy. Most (56%) respondents also indicated that they would consider purchasing a Plug-in Hybrid Electric Vehicle (PHEV) if it were to cost $6000 more than its conventional, gasoline-powered counterpart. And many respond strongly to signals on the external (health and climate) costs of a vehicle’s emissions, more strongly than they respond to information on fuel cost savings.Twenty five-year simulations of Austin’s household vehicle fleet suggest that, under all scenarios modeled, Austin’s vehicle usage levels (measured in total vehicle miles traveled or VMT) are predicted to increase overall, along with average vehicle ownership levels (both per household and per capita). Under a feebate, HEVs, PHEVs and Smart Cars are estimated to represent 25% of the fleet’s VMT by simulation year 25; this scenario is predicted to raise total regional VMT slightly (just 2.32%, by simulation year 25), relative to the trend scenario, while reducing CO2 emissions only slightly (by 5.62%, relative to trend). Doubling the trend-case gas price to $5/gallon is simulated to reduce the year-25 vehicle use levels by 24% and CO2 emissions by 30% (relative to trend).Two- and three-vehicle households are simulated to be the highest adopters of HEVs and PHEVs across all scenarios. The combined share of vans, pickup trucks, sport utility vehicles (SUVs), and cross-over utility vehicles (CUVs) is lowest under the feebate scenario, at 35% (versus 47% in Austin’s current household fleet). Feebate-policy receipts are forecasted to exceed rebates in each simulation year.In the longer term, gas price dynamics, tax incentives, feebates and purchase prices along with new technologies, government-industry partnerships, and more accurate information on range and recharging times (which increase customer confidence in EV technologies) should have added effects on energy dependence and greenhouse gas emissions. 相似文献
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乌锡铁路黄河特大桥桥址位于三湖河口至昭君坟段,北岸为乌拉山山前倾平原,南岸为鄂尔多斯台地,桥址主河道宽710 m,水深3~20 m左右,处于严重的流凌河段,搭建施工栈桥成功与否是确保黄河特大桥顺利施工的关键所在。通过方案比选,确定采用浮桥方式,解决了流凌段栈桥的快速搭拆施工难题,取得了一定的经验。 相似文献
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隧道及地下工程建设面临着大而多的风险,尤其是越江隧道的建设更为突出。因此隧道工程项目风险管理也越来越受到工程建设领域的关注。以规划中的重庆两江隧道为依托,采用风险分析方法中常用的专家打分法,对该工程采用钻爆法可能遇到的风险因素实施风险分析与评估,并给出了相应的处置措施。希望能对该工程以及类似工程的实施提供一些参考。 相似文献
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