The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent notonly on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomic interacti...The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent notonly on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomic interactionsin condensed environment.The real parts of the polarizabilities calculated usually by using the famous Kramers-Kronigtransformation (KKT) from the photoabsorption cross sections of the isolated atoms are very sensitive to the accuracyof the implementation method of the infinite integral in the KKT.The influence of the integral instability of the KKTand the real part of the polarizability on the variation of the photoabsorption cross sections with the number densityand the structure of the condensed matter has been studied in the present work for the first time.The conclusion is thatthe integration method with interpolation has given more reasonable results than the direct truncation method if someappropriate interpolation functions have been used.Some notes and conclusions have also been given for the applicationsof the alternative coupled expressions of photoabsorption cross sections.展开更多
针对多变量时序(Multivariate Time Series,MTS)分类中长序列数据难以捕捉时序特征的问题,提出一种基于双向稀疏Transformer的时序分类模型BST(Bidirectional Sparse Transformer),提高了MTS分类任务的准确度.BST模型使用Transformer框...针对多变量时序(Multivariate Time Series,MTS)分类中长序列数据难以捕捉时序特征的问题,提出一种基于双向稀疏Transformer的时序分类模型BST(Bidirectional Sparse Transformer),提高了MTS分类任务的准确度.BST模型使用Transformer框架,构建了一种基于活跃度得分的双向稀疏注意力机制.基于KL散度构建活跃度评价函数,并将评价函数的非对称问题转变为对称权重问题.据此,对原有查询矩阵、键值矩阵进行双向稀疏化,从而降低原Transformer模型中自注意力机制运算的时间复杂度.实验结果显示,BST模型在9个长序列数据集上取得最高平均排名,在临界差异图中领先第2名35.7%,对于具有强时序性的乙醇浓度数据集(Ethanol Concentration,EC),分类准确率提高30.9%.展开更多
基金Supported by the Natural Science Foundations of Ludong University under Grant Nos.22270301 and L20072804
文摘The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent notonly on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomic interactionsin condensed environment.The real parts of the polarizabilities calculated usually by using the famous Kramers-Kronigtransformation (KKT) from the photoabsorption cross sections of the isolated atoms are very sensitive to the accuracyof the implementation method of the infinite integral in the KKT.The influence of the integral instability of the KKTand the real part of the polarizability on the variation of the photoabsorption cross sections with the number densityand the structure of the condensed matter has been studied in the present work for the first time.The conclusion is thatthe integration method with interpolation has given more reasonable results than the direct truncation method if someappropriate interpolation functions have been used.Some notes and conclusions have also been given for the applicationsof the alternative coupled expressions of photoabsorption cross sections.