针对当前分布式潜在因子推荐算法存在时间复杂度较高、运行时间较长的问题,文中提出基于LU分解和交替最小二乘法(ALS)的分布式奇异值分解推荐算法,利用ALS利于分布式求解目标函数的特点,提出网格状分布式粒度分割策略,获取相互独立不相...针对当前分布式潜在因子推荐算法存在时间复杂度较高、运行时间较长的问题,文中提出基于LU分解和交替最小二乘法(ALS)的分布式奇异值分解推荐算法,利用ALS利于分布式求解目标函数的特点,提出网格状分布式粒度分割策略,获取相互独立不相关的特征向量.在更新特征矩阵时,使用LU分解求逆矩阵,加快算法的运行速度.在KDD CUP 2012 Track1中的腾讯微博数据集上的实验表明,文中算法在确保一定推荐精度的前提下,大幅提升推荐速度和算法效率.展开更多
High performance liquid chromatography(HPLC) is one of the analytical techniques used most frequently. Its chief limitation lies in the need to avoid the overlap of chromatographic peaks as much as possible. In this p...High performance liquid chromatography(HPLC) is one of the analytical techniques used most frequently. Its chief limitation lies in the need to avoid the overlap of chromatographic peaks as much as possible. In this paper, the overlapped chromatograms and spectra system of 1-chloro-2,4-dinitrobenzene and 3,5-dinitrobenzoic acid in the presence of 2,4-dinitrobenzoic acid were resolved by using the alternating trilinear decomposition(ATLD) combined with HPLC-DAD. Moreover, both were determined simultaneously, whose recoveries were(102.1±2.2)% and(97.6±3.6)%, respectively. The satisfactory results show that this experiment can be easily performed without paying out time-consuming and complicated procedures and quantifying accurately. It revealed the ATLD algorithm was one of the approaches to solve second-order calibration problem in HPLC-DAD.展开更多
建立了超声探测缺陷回波的数学模型,讨论了信号奇异性同其小波变换之间的关系以及通过小波变换模极大值精确重构原信号的原理和方法,利用M a llat的交替投影算法对仿真的超声信号进行了精确重构和对实际检测到的超声信号进行了消噪处理...建立了超声探测缺陷回波的数学模型,讨论了信号奇异性同其小波变换之间的关系以及通过小波变换模极大值精确重构原信号的原理和方法,利用M a llat的交替投影算法对仿真的超声信号进行了精确重构和对实际检测到的超声信号进行了消噪处理。结果表明,利用小波变换模极大值重构信号的交替投影算法来重构超声信号,重构精度高,实现速度快,用于处理染噪信号,消噪效果好,是一种较为理想的处理超声信号的方法。展开更多
文摘针对当前分布式潜在因子推荐算法存在时间复杂度较高、运行时间较长的问题,文中提出基于LU分解和交替最小二乘法(ALS)的分布式奇异值分解推荐算法,利用ALS利于分布式求解目标函数的特点,提出网格状分布式粒度分割策略,获取相互独立不相关的特征向量.在更新特征矩阵时,使用LU分解求逆矩阵,加快算法的运行速度.在KDD CUP 2012 Track1中的腾讯微博数据集上的实验表明,文中算法在确保一定推荐精度的前提下,大幅提升推荐速度和算法效率.
文摘High performance liquid chromatography(HPLC) is one of the analytical techniques used most frequently. Its chief limitation lies in the need to avoid the overlap of chromatographic peaks as much as possible. In this paper, the overlapped chromatograms and spectra system of 1-chloro-2,4-dinitrobenzene and 3,5-dinitrobenzoic acid in the presence of 2,4-dinitrobenzoic acid were resolved by using the alternating trilinear decomposition(ATLD) combined with HPLC-DAD. Moreover, both were determined simultaneously, whose recoveries were(102.1±2.2)% and(97.6±3.6)%, respectively. The satisfactory results show that this experiment can be easily performed without paying out time-consuming and complicated procedures and quantifying accurately. It revealed the ATLD algorithm was one of the approaches to solve second-order calibration problem in HPLC-DAD.
文摘建立了超声探测缺陷回波的数学模型,讨论了信号奇异性同其小波变换之间的关系以及通过小波变换模极大值精确重构原信号的原理和方法,利用M a llat的交替投影算法对仿真的超声信号进行了精确重构和对实际检测到的超声信号进行了消噪处理。结果表明,利用小波变换模极大值重构信号的交替投影算法来重构超声信号,重构精度高,实现速度快,用于处理染噪信号,消噪效果好,是一种较为理想的处理超声信号的方法。