中板轧机主传动万向接轴辊端接头断裂事故分析

采用机械测试、三维有限单元、金相组织分析等现代综合分析技术 ,对中板轧机主传动万向接轴辊端接头断裂事故进行分析。事故的主要原因是热处理工艺不当     

浅谈软土桥台病害的分析与评价

介绍了定性分析法、实证分析法、定量分析法、正反分析法、桩土相互作用分析法几种软土地区桥台病害的评价方法,指出了各方法的适用性、可操作性及未来的发展趋势,从而为旧桥台的养护维修、改造加固决策提供有力的支持。     

Study of the structure of the air and blood capillaries of the gas exchange tissue of the avian lung by serial section three-dimensional reconstruction

We have previously reconstructed the gas exchange tissue of the adult muscovy duck, Cairina moschata using a method of manually aligning sections and tracing the contours of the components of the gas exchange tissue. This reconstruction method demonstrated that the air capillaries are comprised of an expanded globular part interconnected by narrow air channels. The blood capillaries completely surround the air capillaries forming an anastomosing meshwork of short segments. However, the resulting reconstruction was limited in scope because of the laborious process of tracing the profiles of each component through the sequence of micrographs. We have now reconstructed a larger proportion of the exchange tissue by using a cross-correlation based alignment strategy and have demonstrated that the staining intensity of each of the exchange tissue components is sufficiently different to allow them to be identified by simple filtering and thresholding. The resulting reconstructions sample a much larger proportion of the exchange tissue and demonstrate the heterogeneity of structures from different locations in the parabronchus. We have shown that a sheet-flow-type arrangement of blood capillaries surrounds the infundibulum; this represents an unexpected functional convergence with the arrangement of blood capillaries surrounding the mammalian alveoli. It is feasible, using this reconstruction strategy, to analyse the exchange tissue of a large number of avian species in order to determine structural correlates of function. The resulting reconstructions could be analysed in order to determine the basis of the functional efficiency and rigidity of the avian lung.     

单工序少无毛边锻造过程预制坯形状优化设计

针对单工锻造在终锻之前一般都需要以镦粗进行预制坯的实际情况，通过刚粘塑性有限元法，以实际锻件超出预定值线部分的体积为目标函数，以镦粗的压下量为优化设计变量，采用黄金分割法对其预制坯工艺化设计进行了研究。并对一轴对称锻件的镦粗压下量进行了优化设计，优化取得了明显的效果。     

小浪底工程孔板洞中闸室及前渐变段结构特性研究

采用三维线弹性有限元法，研究了小浪底水利枢纽孔板洞中闸室段在内压和外压作用下围岩、衬砌混缔造 应力和变位。通过对比分析，找出了结构设计的控制条件，并对通气孔的存在给结构带来的影响和中闸室的整体稳定等问题作出了评价。     

On the Triple Square and the Diagonal of the Golden Section

Geometer Mark Reynolds demonstrates the use of an ancient system for new ways of thinking and seeing: on the triple square and the diagonal of the Golden Section.     

浅谈施工项目的安全控制

阐述了项目经理部应建立安全管理体系和安全生产责任制,从控制人的不安全行为、控制物的不安全状态、改善作业环境、安全生产的科学管理几个方面探讨了项目管理安全控制,以保证施工项目的顺利进行。     

一起车辆事故的定性和统计引发的思考

针对当前公安机关内部在车辆事故火灾的定性和统计工作中存在的分歧，结合当前的法律法规的规定，提出类似车辆事故火灾的定性和统计意见以及解决分歧的建议。     

A microwave transmission-line network guiding electromagnetic fields through a dense array of metallic objects

We present measurements and simulations of a transmission-line network that has been designed for cloaking applications in the microwave region. Here the network is not used for cloaking but for channelling electromagnetic fields through an electrically dense array of metal objects, which alone is basically impenetrable to the impinging electromagnetic radiation. With the designed transmission-line network the waves emitted by a source placed in an air-filled waveguide are coupled into the network and guided through the array of metallic objects. Our goal is to illustrate the simple manufacturing, assembly, and the general feasibility of cloaking devices based on the transmission-line approach. Most importantly, we demonstrate both with measurements and with numerical simulations the excellent coupling of waves between the network and the surrounding medium.     

径向多节扩孔灌注桩受力机理浅析

径向多节扩孔灌注桩是通过发挥栏身中承力扩大盘的承载能力 ,以达到提高单桩坚向承载力的一种新型钻孔灌注桩 ,本文介绍该桩的成桩设备和施工工艺以及在武汉某高层建筑桩基工程中的应用。