The valence band offsets of the strained and longitudinally relaxed diamond/cubic boron-nitride （c-BN） （110） superlattice are investigated by the plane wave density functional theory approach and using the on-site...The valence band offsets of the strained and longitudinally relaxed diamond/cubic boron-nitride （c-BN） （110） superlattice are investigated by the plane wave density functional theory approach and using the on-site core electron as a reference energy level. For the strained diamond/c-BN superlattice, the valence band offset of around 1.50 eV is in good agreement with those using all the electrons methods. As for the longitudinally relaxed superlattice, the valence band offset of around 1.28 eV is smaller than that of the strained superlattice. The reason for this is mainly due to the split of the valence band maximum caused by the anisotropic strain.展开更多
The principle of the support vector regression machine（SVR） is first analysed. Then the new data-dependent kernel function is constructed from information geometry perspective. The current waveforms change regularly...The principle of the support vector regression machine（SVR） is first analysed. Then the new data-dependent kernel function is constructed from information geometry perspective. The current waveforms change regularly in accordance with the different horizontal offset when the rotational frequency of the high speed rotational arc sensor is in the range from 15 Hz to 30 Hz. The welding current data is pretreated by wavelet filtering, mean filtering and normalization treatment. The SVR model is constructed by making use of the evolvement laws, the decision function can be achieved by training the SVR and the seam offset can be identified. The experimental results show that the precision of the offset identification can be greatly improved by modifying the SVR and applying mean filteringfrom the longitudinal direction.展开更多
The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accu...The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accurate satisfaction of the boundary condition on theouter conductor.The combined method of the Gauss elimination and optimization is used tosolve the equation of charge simulation,and it is an effective method for increasing the accuracyand assuring the convergence.The Green’s functions of five transmission lines(i.e,with circular,elliptic,rectangular,trough and slab conductor)are given.展开更多
八元数偏移线性正则变换(octonion offset linear canonical transform,OOLCT)作为八元数线性正则变换(octonion linear canonical transform,OLCT)的推广形式,在高维非平稳信号时频调控中具有优势,但八元数非结合性使传统概率统计量定...八元数偏移线性正则变换(octonion offset linear canonical transform,OOLCT)作为八元数线性正则变换(octonion linear canonical transform,OLCT)的推广形式,在高维非平稳信号时频调控中具有优势,但八元数非结合性使传统概率统计量定义失效,且现有研究多聚焦四元数域,缺乏三维OOLCT(3D-OOLCT)域的严谨概率框架。本文将基础概率理论引入3D-OOLCT领域,构建兼容八元数特性的概率体系:首先,定义3D-OOLCT域中八元数值概率密度函数、分布函数、均值及特征函数;其次,证明特征函数定理;最后,通过算例推导验证特定概率密度函数在3D-OOLCT域的特征函数表达式。该研究填补OOLCT域与概率理论结合的空白,完善八元数变换理论,为三维高维随机信号统计分析提供新工具,也为后续相关工程应用奠定数理基础。展开更多
基金supported by the National Natural Science Foundation of China (Grant No.60877017)the Innovation Program of Shanghai Municipal Education Commission (Grant No.08YZ04)the Shanghai Leading Academic Discipline Project (Grant No.S30107)
文摘The valence band offsets of the strained and longitudinally relaxed diamond/cubic boron-nitride （c-BN） （110） superlattice are investigated by the plane wave density functional theory approach and using the on-site core electron as a reference energy level. For the strained diamond/c-BN superlattice, the valence band offset of around 1.50 eV is in good agreement with those using all the electrons methods. As for the longitudinally relaxed superlattice, the valence band offset of around 1.28 eV is smaller than that of the strained superlattice. The reason for this is mainly due to the split of the valence band maximum caused by the anisotropic strain.
基金Supported by National Natural Science Foundation of China（ No. 50705030）.
文摘The principle of the support vector regression machine（SVR） is first analysed. Then the new data-dependent kernel function is constructed from information geometry perspective. The current waveforms change regularly in accordance with the different horizontal offset when the rotational frequency of the high speed rotational arc sensor is in the range from 15 Hz to 30 Hz. The welding current data is pretreated by wavelet filtering, mean filtering and normalization treatment. The SVR model is constructed by making use of the evolvement laws, the decision function can be achieved by training the SVR and the seam offset can be identified. The experimental results show that the precision of the offset identification can be greatly improved by modifying the SVR and applying mean filteringfrom the longitudinal direction.
文摘The partial charge simulation method is presented to solve the characteristicimpedance of the transmission line of specific cross section with an offset inner conductor.Thismethod has a higher accuracy due to the accurate satisfaction of the boundary condition on theouter conductor.The combined method of the Gauss elimination and optimization is used tosolve the equation of charge simulation,and it is an effective method for increasing the accuracyand assuring the convergence.The Green’s functions of five transmission lines(i.e,with circular,elliptic,rectangular,trough and slab conductor)are given.
文摘八元数偏移线性正则变换(octonion offset linear canonical transform,OOLCT)作为八元数线性正则变换(octonion linear canonical transform,OLCT)的推广形式,在高维非平稳信号时频调控中具有优势,但八元数非结合性使传统概率统计量定义失效,且现有研究多聚焦四元数域,缺乏三维OOLCT(3D-OOLCT)域的严谨概率框架。本文将基础概率理论引入3D-OOLCT领域,构建兼容八元数特性的概率体系:首先,定义3D-OOLCT域中八元数值概率密度函数、分布函数、均值及特征函数;其次,证明特征函数定理;最后,通过算例推导验证特定概率密度函数在3D-OOLCT域的特征函数表达式。该研究填补OOLCT域与概率理论结合的空白,完善八元数变换理论,为三维高维随机信号统计分析提供新工具,也为后续相关工程应用奠定数理基础。
