用ACAD软件与MSTCAD网架程序联合设计钢管球节点网架结构

通过对MSTCAD空间网架分析设计软件使用实践的总结,介绍利用ACAD软件建立三维几何模型并与MSTCAD软件进行联合分析设计的步骤,同时介绍了快速建模联合分析在钢管球节点矿山网架结构中应用的实例.     

府河随州区段河流水质模拟

通过对湖北省府河随州区段河流现场调查和水质现状监测,应用系统的方法,将河流进行概化,并建立了该河段的一维水质模型,结合2008年的水文资料,应用实测资料进行模型参数的确定。经模型验证,模拟结果与该段河流的实际水质监测结果基本吻合,表明该模型具有一定的合理性和实用性。     

大规格玻璃板在室内装饰中的应用

通过某大厦屋顶花园室内核心筒大规格玻璃装饰板安装施工实例,对大规格玻璃装饰板的安装工艺、质量控制要点等进行了系统分析,阐述了大规格玻璃板在实际安装中的安全性和实用性,以及良好的装饰效果。     

花都区文化艺术中心结构设计

通过对花都区文化艺术中心结构设计的介绍,重点讨论了特殊造型的大跨度结构的设计要点,包括抗震性能、大跨度钢桁架受力特点、楼板应力等问题。     

浅淡被动式门窗中空玻璃U值

简要介绍了国内外被动式建筑节能标准要求,并对中空玻璃传热系数U值几个容易混淆的相关概念加以理解,同时给出传热系数测试方法、测试标准及其运用计算软件的点评,通过运用中空玻璃稳定状态下传热系数U值的计算公式及取值,计算出各种配置中空玻璃的U值,重点论述中空玻璃配置、中空腔气体组成、气体层厚度和玻璃厚度对中空玻璃稳态U值的影响,并分别给出了满足欧洲标准和河北标准对被动式门窗用中空玻璃U_g值的要求的各种配置下的中空玻璃气体层厚度和玻璃厚度范围和较为经济的范围。     

Block adaptive kernel principal component analysis for nonlinear process monitoring

On‐line modeling of multivariate nonlinear system based on multivariate statistical methods has been studied extensively due to its industrial requirements. In order to further improve the modeling efficiency, a fast Block Adaptive Kernel Principal Component Analysis algorithm is proposed. Comparing with the existing work, the proposed algorithm (1) does not rely on iterative computation in the calculating process, (2) combines the up‐ and downdating operations to become a single one (3) and describes the adaptation of the Gram matrix as a series of rank‐1 modification. In addition, (4) the updation of the eigenvalues and eigenvectors is of and high‐precision. The computational complexity analysis and the numerical study show that the derived strategy possesses better ability to model the time‐varying nonlinear variable interrelationships in process monitoring. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4334–4345, 2016     

Fabrication and Property of Mullite Whiskers Frameworks with an Ultrahigh Porosity by Expandable Mesocarbon Microbeads

Mullite whiskers frameworks with an ultrahigh porosity were fabricated by the vapor‐phase reaction of AlF₃, Al₂O₃, and SiO₂ and adding expandable mesocarbon microbeads (MCMB) as a pore‐forming agent. A large volume expansion of 122% for MCMB due to its layered structure occurred during the formation of mullite whiskers, resulting in the expansion of samples and high porosities of 87.7%–98.2% at 50–90 wt% MCMB contents. Perfect whiskers and a lap‐joint structure formed due to the formation of mullites through the vapor‐phase reaction. A bimodal pore structure was achieved from the spaces of the whiskers framework and burning of the expanded MCMB. High compressive strengths of 1.7 to 5.4 MPa were obtained for the porous mullite at porosities of 94.2%–87.7%, which suggested a rigid structure; these strengths at the ultrahigh porosities are attributed to the merit of the framework with high strength whiskers and their strong bonding.     

Oxidation of ZrB2–SiC‐Graphite Composites Under Low Oxygen Partial Pressures of 500 and 1500 Pa at 1800°C

The oxidation behavior of ZrB₂–SiC‐graphite composites under low oxygen partial pressures of 500 and 1500 Pa at 1800°C was investigated. The phase composition and microstructure of the oxidized scale were characterized using TEM, SEM, XRD, XPS, EDS. The analytical results indicated that a low oxygen partial pressure had a remarkable effect on the oxidation mechanism of ZrB₂–SiC‐graphite composites. When oxidized at 1500 Pa, the oxidation kinetics was controlled by the rate of oxygen diffusion into the composite. When the composite was oxidized at 500 Pa, control of the oxidation kinetics changed from the rate of oxygen diffusion to the rate of the oxidation reaction. The rate of oxidation decreased with decreasing oxygen partial pressure. Higher partial pressures of oxygen resulted in less oxidation resistance by the ZrB₂–SiC‐graphite composites.