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目的 鉴于传统的标量坐标延时相空间重构方法存在运算复杂、耗时大、稳定性差等缺点,本文提出了相空间定量分析的一种新方法——“棋盘”映射(tessellated map,TM).方法 首先以逐拍心电波形为列矢量构造二维矩阵X,再通过KL变换得到X的主分量,然后由X的最大特征向量重构X.基于重构误差,从X中筛选出高SNR的正常心拍,得到二维矩阵Y.由模值归一化的Y及其衍生差分阵Z,得到“棋盘格”映射图.通过空白区域的比例、点密度、棋盘映射“位图”3个指标对TM进行定量评估.结果 实验结果表明,TM能够对精神应激和非应激进行区分,能够判断心律失常,能够用于身份识别.结论 TM能够有效地从ECG中提取信息,值得深入研究.“,”Objective The traditional delay time phase space reconstruction method has the disadvantages of complicated operation, time consuming and unstableness. This paper presented a novel approach called Tessellated Map (TM) for ECG phase space quantitative analysis. Methods Firstly, 2-D matrix X with each ECG-cycle as a column vector was constructed. Secondly, the principal components of X based on Karhunen-Loeve Transform (KLT) were gotten to reconstruct X from the first eigenvector of XX~T. Then the high SNR ECG-cycle form X based on reconstruction error was selected, to construct the 2-D matrix Y. Afterwards, TM was gotten from united Y and Z (derived from the difference of Y). Three TM-based quantitative indexes, consisted of ratio of blank zone, density of points and TM Bitmap (TMB) were gotten. Results This approach could differentiate mental stress from non-stress, estimate arrhythmia,and could be used for personal identification. Conclusion TM is a useful way to obtain information from ECG, and has its value for further research.