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131.
文章在论述了生命教育和思想政治教育的内在同一性的基础上,从树立“以人为本”的教育理念、明确渗透生命教育的目标、改革思想政治教育教学内容、创新教育教学方法教育教学、加强师资队伍建设等五方面论述了思想政治教育渗透生命教育的实现路径,具有一定的借鉴意义。  相似文献   
132.
This life cycle assessment case study puts the supply chain contribution of transportation to greenhouse gas emissions in context with other contributors using American wheat grain as a representative product. Multiple locations, species and routes to market are investigated. Transportation contributes 39–56% of the supply chain emissions, whereas there is a 101% intra-species and 62% inter-species variation in greenhouse gas emissions from production, demonstrating that transportation is both of smaller magnitude, and less sensitive than other factors, in particular, field sequestration.  相似文献   
133.
工程项目全寿命周期管理的整体构想   总被引:4,自引:0,他引:4  
针对工程项目传统管理模式中存在的一些自身无法克服的弊端,在提出工程项目全寿命周期管理(Life Cycle Managemetn,简称LCM)概念的基础上,对工程项目全寿命周期管理的整体构想作了深入的探讨。  相似文献   
134.
针对当前广泛使用的文档管理系统较少以安全、效率为目标,无法实现企业文档安全管理和维持较高管理效率的问题,基于文档版本控制技术和生命周期理论,根据文档管理平台功能模块,设计适用于该类企业的文档管理平台,实现企业文档的安全有效管理。  相似文献   
135.
This research studied and compared different construction techniques for the road subgrade, embankment and pavement of different types of roundabout intersections in order to assess their environmental sustainability. A Life Cycle Assessment (LCA) was carried out on double lane, turbo- and flower roundabouts.We considered virgin materials and reclaimed asphalt pavement (RAP) for the pavement construction. Also the environmental effects due to in situ lime stabilization of fine-grained soils were assessed in order to reduce the use of virgin material in road subgrades.The use of reclaimed asphalt pavement (RAP) can lead to a significant reduction in pollutant emissions and energy consumption (especially due to the lesser material transport) – though with a slightly different impact according to the different percentages employed – compared to the pavements constructed with virgin materials. The same consideration can be made for fine soils with in situ lime stabilization: on the one hand, the technique allows to improve significantly the mechanical properties of soils which would be otherwise dumped and, on the other, to provide considerable environmental benefits. The life cycle assessment of the pavement was carried out with the help of the PaLATE software (by comparing different maintenance scenarios) while emissions and energy consumption in the use phase at intersections were evaluated by means of closed-form models (to estimate vehicle delays and speeds of vehicles) and the COPERT software.Finally, the generalized costs covered in the whole life cycle of roundabouts (i.e. sum of construction, maintenance and environmental costs) were assessed and associated to the different construction options.  相似文献   
136.
In order to assess sustainability of products and processes, different methodologies have been developed and used in the last years. In the road pavement construction area, most methodologies used for Life Cycle Assessment (LCA) are essentially focused in the construction phase. The present paper analyses the importance of the use phase of a road in the LCA of different paving alternatives, namely by evaluating energy consumption and gaseous emissions throughout the road pavement’s life. Therefore, a new LCA methodology for road pavements was developed, and the results of its application to a case study involving the construction of alternative pavement structures are discussed. The study intends to assess the influence of using more sustainable paving construction alternatives (asphalt recycling vs. conventional asphalt mixtures), and/or different surface course materials (which have a higher influence on the rolling resistance and, therefore, affect the performance during the use phase). The LCA results obtained for this case study showed that the reductions in energy consumption and gaseous emissions obtained during the use phase, for pavement alternatives with a lower rolling resistance surface course, are higher than the total amount of energy consumption and gas emissions produced during construction. It is therefore clear that some improvements in the characteristics of the surface course may have an effect over the road use phase that will rapidly balance the initial costs and gas emissions of those interventions. The LCA results obtained also showed that the sustainability of pavement construction may also be improved using recycled asphalt mixtures.  相似文献   
137.
Municipal fleet vehicle purchase decisions provide a direct opportunity for cities to reduce emissions of greenhouse gases (GHG) and air pollutants. However, cities typically lack comprehensive data on total life cycle impacts of various conventional and alternative fueled vehicles (AFV) considered for fleet purchase. The City of Houston, Texas, has been a leader in incorporating hybrid electric (HEV), plug-in hybrid electric (PHEV), and battery electric (BEV) vehicles into its fleet, but has yet to adopt any natural gas-powered light-duty vehicles. The City is considering additional AFV purchases but lacks systematic analysis of emissions and costs. Using City of Houston data, we calculate total fuel cycle GHG and air pollutant emissions of additional conventional gasoline vehicles, HEVs, PHEVs, BEVs, and compressed natural gas (CNG) vehicles to the City's fleet. Analyses are conducted with the Greenhouse Gases, Regulated Emissions, and Energy use in Transportation (GREET) model. Levelized cost per kilometer is calculated for each vehicle option, incorporating initial purchase price minus residual value, plus fuel and maintenance costs. Results show that HEVs can achieve 36% lower GHG emissions with a levelized cost nearly equal to a conventional sedan. BEVs and PHEVs provide further emissions reductions, but at levelized costs 32% and 50% higher than HEVs, respectively. CNG sedans and trucks provide 11% emissions reductions, but at 25% and 63% higher levelized costs, respectively. While the results presented here are specific to conditions and vehicle options currently faced by one city, the methods deployed here are broadly applicable to informing fleet purchase decisions.  相似文献   
138.
“欲望”与“宿命论”——解析哈代创作中的悲观意识   总被引:1,自引:0,他引:1  
哈代的小说中浸透着一股浓郁的悲剧气息。透过这层浓郁的悲剧氛围,我们可以感知哈代的生命悲剧意识。但这种悲剧意识的形成并非偶然,而是与哈代所处的历史背景、生活环境以及他本人的人生观、世界观有密切联系。本文拟从人类的欲望、叔本华的生命悲观哲学、宿命论等角度来解析哈代创作中的悲剧意识。  相似文献   
139.
To reduce engine maintenance cost and support safe operation, a prediction method of engine life on wing was proposed. This method is a kind of regression model which is a function of the condition monitoring and failure data. Key causes of engine removals were analyzed, and the life limit due to performance deterioration was predicted by proportional hazards model. Then the scheduled removal causes were considered as constraints of engine life to predicte the final life on wing. Application of the proposed prediction method to the case of CF6-80C2A5 engine fleet in an airline proved its effectiveness.  相似文献   
140.
分析车轮磨耗,预测车轮寿命,对降低车辆运营成本具有重要意义.以苏州地铁2号线拖车车轮为例,比较传统方法和数据拟合方法确定磨耗量的差异.数据拟合方法通过窗函数滤掉偶然录入错误数据,用中值滤波器剔除不满足要求的数据,对预处理后的轮径值进行线性拟合,得到轮径与运行里程线性拟合方程,线性拟合方程斜率即车轮磨耗量.传统分析方法采...  相似文献   
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