For electromagnetic scattering of 3?D complex electrically large conducting targets,a new hybrid algorithm,MoM?PO/SBR algorithm,is presented to realize the interaction of information between method of moment(MoM)and p...For electromagnetic scattering of 3?D complex electrically large conducting targets,a new hybrid algorithm,MoM?PO/SBR algorithm,is presented to realize the interaction of information between method of moment(MoM)and physical optics(PO)/shooting and bouncing ray(SBR).In the algorithm,the COC file that based on the Huygens equivalent principle is introduced,and the conversion interface between the equivalent surface and the target is established.And then,the multi?task flow model presented in this paper is adopted to conduct CPU/graphics processing unit(GPU)tests of the algorithm under three modes,i.e.,MPI/OpenMP,MPI/compute unified device architecture(CUDA)and multi?task programming model(MTPM).Numerical results are presented and compared with reference solutions in order to illustrate the accuracy and the efficiency of the proposed algorithm.展开更多
在模式识别中,特征选择是一种非常有效的降维技术.特征评价标准在特征选择过程中被用于度量特征的重要性,但目前已有的标准存在着只考虑类之间的分离性而未考虑其相关性、无法去除特征之间的分类冗余性以及多用于单变量度量而无法获取...在模式识别中,特征选择是一种非常有效的降维技术.特征评价标准在特征选择过程中被用于度量特征的重要性,但目前已有的标准存在着只考虑类之间的分离性而未考虑其相关性、无法去除特征之间的分类冗余性以及多用于单变量度量而无法获取子集整体最优性等问题.提出一种保留分类信息的特征评价准则(classification information preserving,CIP),并使用多任务学习技术进行实现.CIP是一种特征子集度量方法,通过F范数实现已选特征子集的分类信息与原始数据分类信息的差异最小化,并通过l2,1范数约束选择特征个数.近似交替方向法被用于求解CIP的最优解.理论分析与实验结果表明:CIP选择的最优特征子集不仅最大程度上保留了原始数据类别之间的相关性信息,而且有效地降低了特征之间的分类冗余性.展开更多
文摘For electromagnetic scattering of 3?D complex electrically large conducting targets,a new hybrid algorithm,MoM?PO/SBR algorithm,is presented to realize the interaction of information between method of moment(MoM)and physical optics(PO)/shooting and bouncing ray(SBR).In the algorithm,the COC file that based on the Huygens equivalent principle is introduced,and the conversion interface between the equivalent surface and the target is established.And then,the multi?task flow model presented in this paper is adopted to conduct CPU/graphics processing unit(GPU)tests of the algorithm under three modes,i.e.,MPI/OpenMP,MPI/compute unified device architecture(CUDA)and multi?task programming model(MTPM).Numerical results are presented and compared with reference solutions in order to illustrate the accuracy and the efficiency of the proposed algorithm.
文摘在模式识别中,特征选择是一种非常有效的降维技术.特征评价标准在特征选择过程中被用于度量特征的重要性,但目前已有的标准存在着只考虑类之间的分离性而未考虑其相关性、无法去除特征之间的分类冗余性以及多用于单变量度量而无法获取子集整体最优性等问题.提出一种保留分类信息的特征评价准则(classification information preserving,CIP),并使用多任务学习技术进行实现.CIP是一种特征子集度量方法,通过F范数实现已选特征子集的分类信息与原始数据分类信息的差异最小化,并通过l2,1范数约束选择特征个数.近似交替方向法被用于求解CIP的最优解.理论分析与实验结果表明:CIP选择的最优特征子集不仅最大程度上保留了原始数据类别之间的相关性信息,而且有效地降低了特征之间的分类冗余性.
