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71.
结合现场试验,阐述了高桩码头延寿技术的技术原理和施工工艺。结果表明,该技术可有效脱除混凝土内的氯离子并使有效阻锈剂基团快速渗人到混凝土内部,使钢筋恢复钝化而停止腐蚀,从而显著延长码头使用寿命。  相似文献   
72.
提出多云管理平台的概念和体系架构,结合铁路企业多云管理的特点和要求,梳理微服务平台参考模型及其能力要求.如何协调和处理好多云管理实践中3大关键因素间的关系,决定企业多云管理的成败,最后对典型场景云迁移举例阐述,并对应用成效进行总结.多云管理实践有效的推动企业信息基础设施资源管理的标准化,提升企业信息化和智能化管理效率.  相似文献   
73.
针对降雨诱发边坡失稳的特点,从水分迁移的角度出发,结合非饱和土力学,采用有限元法分析了不同降雨强度作用下边坡内部水分迁移的特征;通过数值模拟得到:降雨作用下,边坡内部孔隙水压力呈层状分布,坡脚处孔隙水压力最大,坡顶次之,坡中最小;边坡中的水分主要沿垂直和倾斜方向迁移,迁移速度由表层向深部逐渐减小,迁移方向也随深度和时间而改变;体积含水率呈非线性分布,且非饱和区非线性化程度较饱和区的高;土体渗透系数随降雨强度的增大而增大,当土体饱和时其渗透系数为饱和渗透系数。  相似文献   
74.
The objectives of this review-based paper were twofold. Firstly, we aimed to explore the need and possibilities for broadening the scope of highway planning by taking account of the residential context, including residential satisfaction. Satisfaction appears to be an interesting, and in our opinion, valuable mediating planning concept between road infrastructure planning and the accompanying external effects on the one hand and household coping strategies on the other. Households living near highway infrastructure are influenced by both positive (i.e. accessibility gains) and negative road-related factors (e.g. noise nuisance and air pollution). Changes in these factors may trigger people to accept the new situation, adjust preferences, try to influence plans and/or even relocate. The second aim was to gain a greater understanding of the influence of both accessibility characteristics and negative externalities on the residential context of households. With respect to context, we make a distinction between residential satisfaction, housing prices and residential relocation. We see changes in residential satisfaction as a potential early predictor of opposition to plans, not only from active opposers but also from the more ‘silent majority’, and as a predictor of housing price changes and residential migration. Insights into residential satisfaction around highways may help transportation planners to relieve locational stress and may also prevent protests and relocations. Our literature review indicated that households prefer to live close to highways to benefit from high regional accessibility, but do not want to contend with the nuisances. This is also reflected in property values. However, the literature appears to put more emphasis on studying the impact of (regional) accessibility and externalities on location behaviour than on residential satisfaction. Because of the added value that the concept of residential satisfaction may provide in road planning, and the limited scientific insights, it is important to gain greater insight into how residential satisfaction is influenced by negative and positive externalities and into how residential satisfaction changes over time—from the stage when new road projects are discussed through to concrete planning, realization and the period after completion. Moreover, it would be worthwhile to gain a deeper understanding of the extent to which house prices, location behaviour and residential satisfaction near highways interrelate.  相似文献   
75.
现场车辙调查表明,路面车辙一般集中在行车道轮迹处,超车道和停车道基本没有车辙,而且车辙较深的路段通常沿车辙带分布着带状泛油.在车辙槽处和停车道上钻心取样,对不同面层的混合料进行对比抽提试验.抽提试验结果显示车辙处沥青产生自下往上的迁移:上面层混合料的油石比增大,中、下面层混合料的油.石比减小.运用非线性粘弹性力学原理解释了沥青迁移的机理,即行车荷载下路面结构产生了剪应力,而剪切应力会产生法向应力.导致沥青材料沿剪切应力的法向产生流动.最后,探讨了减轻沥青迁移的技术措施.  相似文献   
76.
Vertical distribution of sound scattering layers were observed using bottom deployed acoustic doppler current profilers (ADCP) during early spring of 1996 and autumn of 1997 in the Gullmarsfjord on the Swedish west coast. Variations in relative backscatter were interpreted in relation to horizontal water velocities, oxygen saturation as well as differences in the light, salinity and temperature regimes. Net catches revealed that much of the backscatter below 20-m depth was associated with the presence of krill, principally Meganyctiphanes norvegica.Horizontal currents seemed to influence the migration and distribution of krill, which showed weak vertical migration patterns with low abundance during periods of strong intermediate in- and outflows, while during periods with weaker currents, a more regular diel migration occurred. Horizontal water velocities >5 cm s−1 seemed to have the potential to decrease the peak in the backscatter profile. Mean vertical migration rates of krill was 1 cm s−1, while maximum vertical migration rates were estimated to be 2.5–3 cm s−1. The range of the vertical migration was different in 1997 due to severe oxygen deficiency in the bottom water, which prevented the krill from descending >80 m. The commencement of vertical migration correlated closely to the seasonal light conditions. The descent was immediately triggered by sunrise, while ascent occurred with a delay of about 1 h at sunset.  相似文献   
77.
为研究探地雷达(GPR)对路面的缺陷检测识别,针对路用探地雷达信号的处理问题,通过在路面基层内各层界面处埋置金属板,分别对数字滤波、反褶积、波动方程偏移和小波多尺度去噪等方法的处理效果进行对比,提出了对提高异常的分辨率和奇异值分解具有明显效果的方法,并应用于道路现场检测中.结果表明,反褶积和波动方程偏移处理对提高异常的...  相似文献   
78.
企业在面对信息资源整合及资源开发利用时,及时引进先进、适用的云计算技术,是降低成本、提高数据存储效率、加快应用开发速度和提高信息系统稳定性的有效方式之一.详细阐述构建企业级云平台的建设思路,通过实际工程案例,介绍某航运企业如何利用“云计算”虚拟化技术和数据同步复制技术,实现企业级的服务器资源整合和系统虚拟化迁移.  相似文献   
79.
In an atrocious ocean environment,the lateral propulsion hole could potentially be partly out of water and capture an air cavity.Bubbles would form when the captured air cavity escapes underwater and they may affect the performance of the sonar.The common commercial computational fluid dynamics software CFX was adopted to calculate the ambient flow field around the lateral propulsion hole generated by a moving vessel.The oscillation of the spherical bubble was based on the Rayleigh-Plesset equation and its migration was modeled using the momentum equation.The radiated noise of the oscillating bubble was also studied.The aim is that the results from this paper would provide some insight into corresponding fluid and acoustic study.  相似文献   
80.
host是备份windows操作系统常用的工具和方法,但对Linux系统备份还原则有文件系统兼容问题.Linux备份还原专用工具G4L完成作业的进程缓慢,运行时间长.本文阐述用希捷的碰盘工具-seagate DiscWizard,在Windows7视窗界面下快速完成Linux系统的备份、还原和异机迁移,以及作业中的注意事项和优缺点.  相似文献   
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