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271.
文章概述了近年来国内外加筋土界面特性室内试验研究的进展,按直剪试验、拉拔试验、三轴试验等内容进行分类,总结取得的规律性成果,分析讨论所存在的问题,并提出了进一步研究的看法。这些分析对理清加筋机理具有重要意义,同时也为加筋工程提供设计参数。 相似文献
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This paper looks at the environmental effects of shifting from road to rail freight transportation. Little data is available to shippers to calculate the potential CO2 savings of an intermodal shift. In this paper we analyze a data set of more than 400,000 intermodal shipments to calculate the CO2 intensity of intermodal transportation as a distinct mode. Our results indicate an average intensity of 67 g of CO2 per ton-mile, but can vary between 29 and 220 g of CO2 per ton-mile depending on the specific origin–destination lane. We apply the market area concept to explain the variance between individual lane intensities and demonstrate the complexity in predicting the potential carbon savings in a switch from truckload to intermodal. 相似文献
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Tim Schwanen David BanisterJillian Anable 《Transportation Research Part A: Policy and Practice》2011,45(10):993-1006
This paper seeks to develop a deeper understanding of the research on climate change mitigation in transport. We suggest that work to date has focused on the effects of improvements in transport technologies, changes in the price of transport, physical infrastructure provision, behavioural change and alternative institutional arrangements for governing transport systems. In terms of research methodologies, positivist and quantitative analysis prevails, although there are signs of experimentation with non-positivist epistemologies and participatory methods. These particular engagements with climate change mitigation reflect mutually reinforcing tendencies within and beyond the academic transport community. We first draw on a revised version of Thomas Kuhn’s philosophy of science to explore the path dependencies within transport studies, which are at least partly responsible for the predisposition towards quantitative modelling and technology, pricing and infrastructure oriented interventions in transport systems. We then employ the governmentality perspective to examine how transport academics’ engagements with climate change mitigation depend on and align with more general understandings of climate change in UK society and beyond. The analysis makes clear that ecological modernisation and neo-liberal governmentality more generally provide the context for the current focus on and belief in technological, behaviour change, and especially market-based mitigation strategies. While current research trajectories are important and insightful, we believe that a deeper engagement with theoretical insights from the social sciences will produce richer understandings of transport mitigation in transport and briefly outline some of the contributions thinking on socio-technical transitions and practice theories can make. 相似文献
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选用北京培特公司技术开发的HT8002AC井式炉渗碳/碳氮共渗工艺过程计算机控制系统,技术改进2台RJJ-75-9TG井式气体渗碳炉的渗碳控制系统,实现计算机对整个工艺渗碳全过程的模拟控制,并时刻跟踪和修正现场设备参数的动态变化。提升了渗碳件的产品质量,确保汉德公司两到三年之内的自制件,能够达到国际出口标准。 相似文献
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碳纤维复合材料在桥梁工程中的应用 总被引:4,自引:0,他引:4
简要介绍碳纤维复合材料(CFRP)的材料特性和在新建桥梁结构及危旧桥补强加固等工程中的应用。并展望了该种材料在今后的发展与应用前景。 相似文献
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