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971.
面对政府统计工作改革和行业决策管理的双重要求,针对公路货物运输量统计数据受外部 因素干扰,存在较严重准确性的问题,从控制省级上报统计数据质量角度入手,在研究不同评估方法对公路货运量的适用性基础上,提出了一种基于相关性和正态分布的异常值检验方法。从行 业数据内部协调性和外部数据匹配性的角度,选取了高度相关的判别指标作为评估依据,构造了判别指标与货运量的发展速率比服从正态分布的检验统计量。在给定的显著性水平下计算该统计 量并进行异常值诊断,检验各省货运量增长速度的截面数据是否偏离正态分布成为异常值,以此建立公路运输量统计评估模型,为开展公路货物运输量数据质量评估工作提供指导。结果表明,在实际工作中,该方法可以有效诊断出数据异常省份并指导其进行数据核实和修正,有助于建立长期质量评估机制,从而反映公路运输业真实发展情况,为行业提供更有效、更可靠的统计信息 服务。  相似文献   
972.
物流调查是物流设施规划与政策制定的重要基础。物流数据统计发展滞后已成为制约中国物流业发展的重要瓶颈。通过梳理日本在物流调查方面的工作进展,总结其在调查制度保障、组织模式、调查方案、调查内容及方法等方面的特点。针对中国物流行业发展现状,提出具体建议:加快开展货运需求调查的前瞻性研究,规范并指导企业构建统一的物流信息数据与平台,远期将货运调查纳入综合交通调查体系等。  相似文献   
973.
周健 《交通标准化》2020,6(3):14-22
为了研究新冠肺炎疫情对交通运输行业造成的影响,首先分析了SARS疫情对交通运输行业的影响,然后结合我国当前经济发展特征,就新冠肺炎疫情对交通运输行业的影响进行了分析。研究认为,新冠肺炎疫情对交通运输行业的影响是短期的,不会造成长期趋势性改变;新冠肺炎疫情对交通运输行业的影响远超过SARS疫情;交通运输各个领域恢复期将表现出明显差异。最后,有针对性地提出一些应对新冠肺炎疫情影响的措施建议,供各级交通运输管理部门决策参考,具体包括切实做好新冠肺炎疫情影响程度更深的应对准备;提供安全可靠的客运服务;不断提升交通运输行业应急处置能力;建立交通运输行业重大危机救助基金。  相似文献   
974.
在分析我国公路快速货运企业发展现状及存在问题的基础上,探讨公路快速货运与物流的内在联系机制和我国公路快速货运企业的物流发展定位,并从专业物流角度,提出我国公路快速货运企业发展和提升的客户拓展、快运一体化、物流差异化、网络构建等策略,以此来填补理论与实践之间的空隙.  相似文献   
975.
This paper aims to evaluate the likely effects of the adoption of Longer Heavier Vehicles (LHVs) from the perspective of logistics service providers (LSPs). The research consists of six case studies and a survey of companies which were involved LHV trials in Germany. Wider introduction of LHVs is being increasingly demanded so that road freight transport can better serve and support modern supply chains whilst achieving the desired eco-efficiency advancements. Available literature on LHVs puts a particular emphasis on five factors that need to be included in the assessment of their impact: energy efficiency, CO2 emissions, costs, safety and infrastructure. The research provides an original and innovative empirical study refining and validating the current conceptual framework for assessing LHVs demonstrating it is a valuable tool and providing evidence that the vast majority of companies participating in our study, regardless of their size, were interested in the adoption of LHVs. However, it should be noted that a key limitation of the research is that by focusing on a single country case, the nature and scale of the findings may not reflect practice in other countries and sectors. There is also a need to examine the long-term sustainability of the improvements made.  相似文献   
976.
Electric Freight Vehicles (EFVs) are a promising and increasingly popular alternative to conventional trucks in urban pickup/delivery operations. A key concerned research topic is to develop trip-based Tank-to-Wheel (TTW) analyses/models for EFVs energy consumption: notably, there are just a few studies in this area. Leveraging an earlier research on passenger electric vehicles, this paper aims at filling this gap by proposing a microscopic backward highly-resolved power-based EFVs energy consumption model (EFVs-ECM). The model is estimated and validated against real-world data, collected on a fleet of five EFVs in the city centre of Rome, for a total of 144 observed trips between subsequent pickup/delivery stops. Different model specifications are tested and contrasted, with promising results, in line with previous findings on electric passenger vehicles.  相似文献   
977.
There is a large body of research related to carbon footprint reduction in supply chains and logistics from a wide range of sectors; however the decarbonisation of freight transport is mostly explored from a single mode perspective and at a domestic/regional level. This paper takes into account a range of alternative transport modes, routes and methods with particular reference to UK wine imports from two regions: northern Italy and Southeast Australia. The research examines supply chain structures, costs and the environmental impact of international wine distribution to the UK. A number of options are evaluated to calculate the carbon footprint and sulphate emissions of alternative route, mode, method of carriage, and packaging combinations. The estimation of CO2e emissions incorporates three main elements - cargo mass, distance and method of carriage; sulphate emissions are derived from actual ship routes, engine power and operational speeds. The bottling of wine either at source or close to destination is also taken into consideration. The key findings are: there are major differences between the environmental footprint of different routeing and packaging scenarios; the international shipping leg almost always has a much larger footprint than inland transport within the UK except in the hypothetical case of the rail shipments from Italy using flexitanks. With reference to sulphate, the lowest cost scenario among the sea maximizing options is also the sulphate minimising solution.  相似文献   
978.
This paper analyzes the influence of transient operating modes in the Cat 3512B-HD and MTU 4000 R41 locomotive diesel engines on their energy usage. This analysis represents an integral component of the technological research and development performed at Lietuvos Geležinkeliai AB (JSC Lithuanian Railways) with the objective of increasing the efficiency of freight transportation with the upgraded 2M62M and modern ER20CF/2ER20CF diesel locomotives. The influence of transient modes on the operating variables of the locomotive diesel engines was evaluated under operational load-cycling conditions to aid in the selection of appropriate parameters (e.g., the train weight, the diesel locomotive type, and the technical characteristics of the diesel locomotive to be modeled) for freight transportation on Lithuanian railway lines. It was determined that the engine’s electronic control system compensates for the negative effects of transient operations on the engine’s energy usage. As a result, the increase in fuel consumption is less than 3% during transient operation when compared to steady-state operation. Through this research, methodological foundations have been formulated and adapted for the use of the mathematical modeling of the transient modes of locomotive diesel engines to optimize freight transportation, resulting in an expected decrease of 10–15% in fuel consumption.  相似文献   
979.
980.
Reducing the empty weight of articulated heavy goods vehicle trailers is one avenue that needs to be explored in reducing the carbon footprint of the road freight industry as a whole. A statistical analysis of two heavy goods vehicle fleets operating in the United Kingdom has helped to identify double-deck trailers used in grocery haulage and ‘walking-floor’ trailers used in bulk haulage as two examples of trailers that can benefit significantly from lightweighting. Energy consumption of numerous articulated heavy goods vehicles is quantified through an idealised drive cycle analysis reflecting a long haul journey over a highway. This energy analysis allows for a mass energy performance index to be established. The analysis has shown that reducing the empty weight of trailers by 30% can cause reductions of up to 18% and 11% in mass energy performance index for double-deck trailers and ‘walking-floor’ trailers respectively. Using this approach, trailers that will benefit the most from weight reduction can be identified systematically, allowing for lightweighting strategies to be implemented more effectively. Strategies to reduce empty trailer weight and improve vehicle utilisation are also discussed.  相似文献   
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