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31.
In order to estimate the reliability of wind turbine gearbox based on the system level, a generalized stress-strength model is introduced. Considering that the system works properly under a variety of random stresses which affect every component, the total stress on the system is given by a known linear combination of the stresses of all components. Then the strength of the system can be viewed as a linear combination of the strengths of relative components. In this model, stress and strength are independent of each other. Reliability of the system is the probability that strength exceeds stress. Finally, the reliability of wind turbine gearbox is estimated by the multivariable reliability calculation method. The corresponding result is compared with the results of reliability in the extreme cases(completely dependent and completely independent) by the traditional evaluation method. 相似文献
32.
航海仪器的现状与未来发展 总被引:2,自引:0,他引:2
阐述了船舶指向仪器、定位仪器和避碰仪器的现状及未来发展;以及实现真正意义上的船舶自动航行的可行性。 相似文献
33.
在竖井送排式通风时,排风口和送风口之间可能产生短道流动,这种短道流动会阻碍隧道内的空气交换。将以某分段纵向通风特长公路隧道为例,主要运用CFDesign软件,对短道进行数值仿真模拟,通过模拟得出不同的短道长度,不同送排比对隧道回流状况的影响,通过对比,确定短道的最佳长度。 相似文献
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Partial safety factors must be evaluated precisely for the given target reliability index to ensure the certain level of structural reliability due to uncertain factors. The current studies of partial safety factors do not consider human error in construction for structural reliability. A mathematically model should be improved to simulate the partial safety coefficient concerned uncertainty factors which concern the effect of human error in construction. We employ the contaminated distribution to obtain the realistic mean value and standard variance of variable of structural parameters which coexist with random error human error. The reasonable partial safety coefficient can be calculated based on the realistic value of structural parameters concerned the effects of random error and gross error. 相似文献
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The metallurgical structure and composition of ingots which depend critically on the fluid motion within the molten pool during
the vacuum arc remelting (VAR) process have important effect on the subsequent mechanical processes like forging, rolling
and welding. In order to determine the fluid motion of molten pool, a 2D finite element model is established using ANSYS10.0
software, combined with the turbulent fluid flow and heat transfer. The fluid motion caused by thermo buoyancy forces is investigated
at different VAR processes in the present study. The results indicate that the fluid flows symmetrically along the axis of
the molten pool and clockwisely along the circle at the right pool’s profile. It is also shown that the maximum velocity increases
with increasing melting rate and a direct proportional relationship exists. 相似文献
39.
地铁瓦斯隧道安全防控管理体系研究与应用 总被引:1,自引:0,他引:1
针对地铁工程穿越瓦斯地层时所面临的危险源种类繁多、安全管理难度大等难题,利用物联网、流媒体和无线传输等技术,集成瓦斯自动检测、盾构施工实时监控、人员定位等专业应用,提出了全线覆盖、全员参与、全过程管理的集约化管控模式,构建了各参与方共同监管的地铁瓦斯隧道安全防控管理体系.该体系已成功应用于成都轨道交通6号线三期工程的全过程建设中.通过线上、线下联动管理的方式,对地铁线路穿越瓦斯地层时土建施工阶段的危险源进行实时智能化监测、迅速响应和及时处置,有效提高了施工过程中的安全风险管理水平,节约了管理成本. 相似文献
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