A novel strategy on combining variational mode decomposition (VMD) and composite weighted-scale sample entropy (CWSE) modified from composite multiscale entropy (CMSE) is proposed to screen hepatocellular carcinoma (HCC) by measuring the terahertz (THz) pulse signals of ten normal and ten HCC serums. Eight measured HCC specimens are negative in serum biomarker alpha fetoprotein (AFP) determination. In CWSE, the time series with weighted-scales are generated from the weighted average processing in the coarse-grained time series corresponding to each scale of the CMSE algorithm. VMD served as a preprocessing method was introduced into decomposing THz signal to obtain the mode functions of specific bandwidth for identification. Final results reveal that more obtainable entropy values of CWSE for recognition in comparison to those of CMSE on the basis of the rule of statistically significant difference and effect size and also manifest the stronger discriminability than the traditional THz parameters. This study provides a new potential auxiliary tool for diagnosis HCC and develops the methodology on the discrimination for similar THz signals.

中文翻译：

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基于太赫兹信号和VMD-CWSE的肝细胞癌诊断


提出了一种将变分模态分解（VMD）与复合多尺度熵（CMSE）改进的复合加权尺度样本熵（CWSE）相结合的新策略，通过测量十个正常人的太赫兹（THz）脉冲信号来筛查肝细胞癌（HCC）和十份 HCC 血清。八个测量的 HCC 标本的血清生物标志物甲胎蛋白 (AFP) 测定呈阴性。在CWSE中，带有加权尺度的时间序列是通过对CMSE算法的每个尺度对应的粗粒度时间序列进行加权平均处理而生成的。 VMD作为一种预处理方法被引入到太赫兹信号的分解中，以获得特定带宽的模式函数以供识别。最终结果表明，根据统计显着性差异和效应大小的规则，CWSE比CMSE更容易获得用于识别的熵值，也表现出比传统太赫兹参数更强的辨别能力。这项研究为诊断 HCC 提供了一种新的潜在辅助工具，并开发了区分类似太赫兹信号的方法。