运动与年龄对心音混沌特性影响规律的研究

研究心音混沌特征随着运动与年龄变化的规律。心音是一种非平稳的非线性信号,具有典型的混沌特性,利用自制的肩带式心音采集装置采集运动环境下和不同年龄段的心音信号,然后对心音信号进行相空间重构,给出在静息、运动中、运动后三种状态下的心音信号混沌吸引子,讨论运动与年龄对心音混沌特性的影响,重点分析心音关联维数的变化规律。实验结果表明:1运动前静息期、运动中期、运动后恢复期的心音信号关联维数具有显著差异性,长期运动会使心音混沌特征参数趋于相对稳定。2随着年龄的增加,受人体心血管系统衰老和病理性杂音的影响,心音信号关联维数呈下降趋势,衰老是心音混沌特性渐变为零的过程。

Influences of exercise and age on heart sound chaotic characteristics

Here, the chaotic characteristics of heart sound influenced by exercise and age were discussed. Heart sound was a kind of non-stationary and nonlinear signals with typical chaotic characteristics. A homemade shoulder belt heart sound-sampling device was used to collect heart sound signals under different movement states and different ages, then they were reconstructed in phase space, the chaotic attractor's of heart sound signals were given under the states of resting, in exercise and after exercise. The effects of exercise and age on chaotic characteristics of heart sound signals were discussed and analyzing the laws of heart sound correlation dimension was focused on. The test results showed that ① the correlation dimensions of heart sound before exercise, in exercise and after exercise have obvious differences, long term exercise makes the chaotic characteristic parameter of heart sound approach into a stable level; ② with increase in age, due to the effects of human cardiovascular system growing older and pathological murmurs, the correlation dimension of heart sound decreases; growing older is a process of chaotic characteristics of heart sound gradually becoming zero.