环形偏置基础对浅圆仓仓壁受力变形特性的影响

为揭示环形偏置基础对浅圆仓仓壁受力变形的影响规律,通过壳体单元和弹簧单元建立了浅圆仓三维有限元分析模型,并对地基及基础约束、基础宽度、基础偏置方式、筒仓高径比和仓壁摩擦力开展了参数分析。结果表明随着底部约束的增强,仓壁底部环向拉力逐渐减少。基础偏置方式和仓壁摩擦力对于仓壁底部弯矩影响较大。因基础向外偏置所产生的“扳手”效应,在仓壁摩擦力、大高径比和弱底部约束叠加作用下仓壁底部的负弯矩远大于仓壁底部固结约束弯矩。

Blind cancellation for frequency offset in OFDM system based on MCMA-RLS algorithm

Modified constant modulus and recursive least squares （MCMA-RLS） algorithm is proposed to cancel interference caused by the variable frequency offset （FO） in the orthogonal frequency division multiplexing （OFDM） system. The MCMA-RLS algorithm is composed of two stages including MCMA scheme and RLS scheme. MCMA is selected to pre-cancel the variable frequency offset firstly, and then the residual interference has been canceled by the RLS scheme. BR error rate is simulated to demonstrate that the proposed method is robust for canceling the variable frequency offset.