This paper discusses a fictitious domain method for the linear Dirichlet problem and its applications to the generalized Stokes problem. This method treats Dirichlet boundary condit ion via a Lagrange multiplier tec...This paper discusses a fictitious domain method for the linear Dirichlet problem and its applications to the generalized Stokes problem. This method treats Dirichlet boundary condit ion via a Lagrange multiplier technique and is well suited to the no-slip bound ary condition in viscous flow problems. In order to improve the accuracy of solu tions, meshes are refined according to the a posteriori error estimate. The mini -element discretization is applied to solve the generalized Stokes problem. Fin ally, some numerical results to validate this method are presented for partial d ifferential equations with Dirichlet boundary condition.展开更多
针对目前极化敏感面阵空域-极化域联合谱估计运算量大、耗时长的问题,提出一种降维求根MUSIC(Multiple Signal Classification)优化算法。通过对接收信号进行降维处理,提出新的求解模型将传统四维MUSIC转化为两个一维求根MUSIC求解空域...针对目前极化敏感面阵空域-极化域联合谱估计运算量大、耗时长的问题,提出一种降维求根MUSIC(Multiple Signal Classification)优化算法。通过对接收信号进行降维处理,提出新的求解模型将传统四维MUSIC转化为两个一维求根MUSIC求解空域波达方向和引用已求解出的空域信息结合拉格朗日乘子法解决来波信号极化信息估计问题。相比传统的4D-MUSIC和秩亏MUSIC,所提算法在不损失估计精度的前提下提高了运算速度,降低了运算复杂度,无需谱峰搜索过程,消除了因搜索步长而导致的量化误差。对日后大规模阵列计算及MIMO(Multiple Input Multiple Output)雷达引入提供快速求解方法。仿真实验表明,所提算法在低信噪比0 dB下空域误差约为0.85°,速度相比秩亏MUSIC提升了约64.7%,验证了该算法的有效性和高精度性。展开更多
文摘This paper discusses a fictitious domain method for the linear Dirichlet problem and its applications to the generalized Stokes problem. This method treats Dirichlet boundary condit ion via a Lagrange multiplier technique and is well suited to the no-slip bound ary condition in viscous flow problems. In order to improve the accuracy of solu tions, meshes are refined according to the a posteriori error estimate. The mini -element discretization is applied to solve the generalized Stokes problem. Fin ally, some numerical results to validate this method are presented for partial d ifferential equations with Dirichlet boundary condition.
