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101.
为解决南方湿热地区沥青路面受紫外光老化影响问题,利用紫外老化环境箱和动态剪切流变仪研究老化时间和受阻胺类抗紫外老化卉l】(GW一944)对沥青高温动态力学性能、低温和疲劳性能的影响。试验结果表明:强紫外光降低了沥青疲劳性能和低温性能,改善了抗车辙性能,且随老化时间延长而加剧;受阻胺类抗紫外老化剂(GW-944)能较好地对SBS改性沥青进行抗老化性能改善,且对其性能改善存在合适的掺量范围,适宜掺量为0.5%,而对基质沥青性能改善并不适用。研究成果为沥青路面有效防治紫外光老化提供了技术依据。 相似文献
102.
运用LabVIEW图形化编程软件,通过结构化设计及模块化编程,设计出车辆动力性能评价仿真系统.该仿真系统考虑了多种参数对车辆动力性能的影响,并且能够处理Excel扭矩数据表格和生成Word报表文档,使用方便,仿真结果准确性较高.利用此仿真结果可进一步优化车辆的结构参数,从而提高车辆的动力性能. 相似文献
103.
There seem to be two types of ocean planning system in the world. First, the federal or united government suggests a basic framework of the plan which is followed by states, countries or areas as shown in the European Union, the United States, Canada, Australia, and so on. Second, a powerful central government prepares a basic ocean plan that guides the following sector plans of the relevant ministries. These cases are shown in Japan, Korea, and China. In Korea, the 2nd Ocean and Fishery Development Plan (OK21, 2011–2020) was made as a comprehensive ocean plan reflecting recent natural and social changes including global warming. The OK21 is declarative in its nature, and so evaluated by its sector plans, which have some specific implementing means such as budgets and manpower, organization, and so on, by the relevant laws. The 2nd OK21 is supported by 21 legally binding sector plans, 14 more than in the 1st plan, thus guaranteeing more effective implementation than in the 1st plan. In addition, most of sector plans are planned to be carried out through the well-coordinated system among the related ministries, thus showing a high degree of implementing efficiency of the plan. Every marine area in the plan, including marine environment, is being supported by more sector plans than before, indicating the equitable development of marine areas in the future. In sum, the 2nd OK21 is expected to show more implementing power due to the well-organized sector plans than in the 1st plan. 相似文献
104.
ABSTRACTThe container shipping industry is receiving growing attention in driving the performance of global supply chains. This phenomenon has accelerated supply chain integration (SCI) within the industry. Although SCI could offer numerous benefits, it is often quoted to be implemented easier in theory than in practice. The high failure rate that is associated with SCI is often not addressed in the literature. Grounded on resource-based view (RBV) theory, this paper is aimed at identifying the critical success factors (CSFs) and examining their influence on SCI and supply chain performance (SCP). Survey questionnaires were administered on 164 container shipping firms. The constructs were validated empirically using confirmatory factor analysis and were subsequently analysed using structural equation modelling. The proposed CSFs in this study are found to be positively corelated with SCI, which, in turn, is positively correlated with SCP. This paper has contributed to both theory and practice by applying RBV theory to identify the key resources and capabilities that are necessary for SCI in the container shipping industry. 相似文献
105.
文章根据电子信息系统的试验需求,结合工程实际,从具体应用人手,讲述一种多平台间信息传输性能测评方法,并对如何实现数据采集与记录、信息传输实时监测、系统性能分析等方面进行了详尽描述,该方法为多平台综合试验提供了有效的评估手段。 相似文献
106.
运用填充理论进行钢渣的级配和石灰、粉煤灰最佳比例的研究,通过对不同级配、不同二灰掺配比例的混合料路用性能比较,提出了一种最佳比例的二灰稳定钢渣混合料,其钢渣构成承重骨架,二灰密实地填充于其空隙中并裹覆其表面.用电镜等手段对其进行了微观分析;用抗压强度和回弹模量评价其力学性能.此项研究对利用钢渣铺路具有一定的借鉴作用. 相似文献
107.
Y.H. Venus Lun Michael BrowneKee-hung Lai Christina W.Y. WongT.C.E. Cheng 《Research in Transportation Economics》2011,32(1):64-70
Container shipping and its related service sectors help accelerate globalization of the world economy. This industry has been experiencing rapid growth, prompting container terminal operators to increase their handling capacity in response. Providing container terminal services requires substantial capital investment in physical assets such as cargo handling facilities and information systems. On the other hand, operating container terminals is a long-term investment that typically spans several business cycles. Hence prudent asset management using appropriate tools is critical for container terminal operators to sustain their businesses. Generally, due to risk-adverseness, investors are unwilling to take more risk in their investment unless they can reap a higher return. Contrary to this argument, this study finds no direct influence of better firm performance as a proxy of higher return on business risk-taking by container terminal operators. Instead, scale of operations is positively associated with business risk-taking, suggesting that container terminal operators with a larger scale of operations are willing to take more business risk. 相似文献
108.
李涛 《铁道标准设计通讯》2012,(10)
介绍宿淮铁路2座特大桥结构体系设计创新特点。理论计算分析表明:采用主跨132 m连续梁-拱组合体系单线桥可有效降低梁高,节省造价,施工和运营状态下,结构的强度、刚度、横向稳定、行车舒适度性等指标均满足规范要求;主跨108 m连续梁采用双向减隔震体系后,正常使用状态及多遇地震下结构正常工作。当设计地震及罕遇地震发生时,减隔震体系显著降低地震反应,避免了重要部位破坏,保证了桥梁结构的安全性,具有明显的经济效果。 相似文献
109.
110.
超薄沥青混凝土面层是一种摊铺厚度为1.5~2.5cm之间的细粒式沥青面层,其主要目的是用于旧路的功能性恢复以及新建公路表面功能层。在大量室内试验的基础上,探索了超薄沥青混合料室内试验评价方法。 相似文献