In-plane elastic stability of fixed parabolic shallow arches

The nonlinear behavior of fixed parabolic shallow arches subjected to a vertical uniform load is inves- tigated to evaluate the in-plane buckling load. The virtual work principle method is used to establish the non-linear equilibrium and buckling equations. Analytical solutions for the non-linear in-plane sym- metric snap-through and antisymmetric bifurcation buckling loads are obtained. Based on the least square method, an approximation for the symmetric buckling load of fixed parabolic arch is proposed to...     

CALA: A Web analysis algorithm combined with content correlation analysis method

Web hyperlink structure analysis algorithm plays a significant role in improving the precision of Web information retrieval.Current link algorithms employ iteration function to compute the Web resource weight.The major drawback of this approach is that every Web document has a fixed rank which is independent of Web queries.This paper proposes an improved algorithm that ranks the quality and the relevance of a page according to users‘ query dynamically.The experiments show that the current link analysis algorithm is improved.     

Effect of suspended sediment grain size on channel sedimentation in the lower Yellow River and some implications

Based on the data of suspended sediment transport and channel sedimentation in various grain size fractions in the period of 1962―1985, the relationship between channel sedimentation in the lower Yellow River and sediment input has been plotted with respect to each grain size fraction. Several fill-scour thresholds in sediment input have been identified from these graphs. It was found that the fill-scour threshold in sediment input decreases with the increase in fraction grain size. The correlation coeffici...     

GH4169合金高温多轴低周疲劳寿命预测

基于临界面模型的方法提出一个新的多轴低周疲劳损伤准则.该准则与目前的临界面法不同的是,在预测多轴低周疲劳寿命的模型中,同时考虑临界面上最大剪应变和正应变在不同加载路径下对多轴低周疲劳损伤的贡献.试验结果表明,文中提出的多轴低周疲劳寿命预测模型,对于GH4169合金高温多轴疲劳寿命估算具有较高的准确性.     

基于电流测量的数控机床切削力误差建模与实时补偿

从数控机床主轴驱动系统的传动机理出发，系统地研究主轴伺服电机电流信号与切削力之间的关系。利用模糊神经网络理论完成切削力误差建模，研制了数控机床的切削力误差实时补偿系统，并通过实例进行了验证。该研究方案避免了传统用测力仪进行切削力监测花费大、调试难、可靠性低等问题，所建切削力误差模型鲁棒性强，具有重要的工程实用价值。     

浅谈科技期刊的版权转让合同

随着国际科技与文化交流日益加强，为保护科技期刊和作者的合法权益，促进科技期刊进一步发展，科技期刊应增强版权保护意识，尽快与作者签署版权转让合同。     

CALA: A Web Analysis Algorithm Combined with Content Correlation Analvsis Method

Web hyperlink structure analysis algorithm plays a significant role in improving the precision of Web information retrieval. Current link algorithms employ iteration function to compute the Web resource weight. The major drawback of this approach is that every Web document has a fixed rank which is independent of Web queries. This paper proposes an improved algorithm that ranks the quality and the relevance of a page according to users' query dynamically. The experiments show that the current link analysis algorithm is improved.     

由周期型强激光脉冲引起的光学元件的温度分布

在本文中,我们根据强激光脉冲的重复频率较低,脉宽窄的特点,把介质在一个周期中受辐照的温升分为辐照阶段和辐照后热扩散阶段处理。在充分考虑辐照脉冲的周期性特征后,得出了稳定周期运行的系统中光学元件上的温度分布。     

上海世界博览会规划设计

由东南大学建筑学院与美国35设计组联合完成的“中国2010年上海世界博览会规划设计方案”荣获Architectural Review杂志2004年城市景观设计二项大奖（Cityscape 2004 Architectural Review Rewards），它们分别是总体规划设计（Master Planning for World Expo 2010 Shanghai China）与世博文化塔设计（People＇s Tower for World Expo 2010 Shanghai China），是本次评奖中唯一同时获得两项大奖的设计方案。     

开发超宽带光学取样示波器工程化样机

简短介绍了超宽带光学取样示波器设备的自主研发工作.通过对光脉冲取样源和全光波形取样门进行创新性设计并且使用新的计算机软件算法对后端数据进行分析处理,成功开发出高可靠性、结构紧凑、光纤型超宽带光学取样示波器工程化样机,并掌握了其工程设计的方法.