Li Xiaoli, Li Chengwei
School of Electrical Engineering and Automation, Harbin Institute of Technology, Harbin 150001, China.
Comput Math Methods Med. 2016;2016:8301962. doi: 10.1155/2016/8301962. Epub 2016 Aug 22.
Diabetes is a serious threat to human health. Thus, research on noninvasive blood glucose detection has become crucial locally and abroad. Near-infrared transmission spectroscopy has important applications in noninvasive glucose detection. Extracting useful information and selecting appropriate modeling methods can improve the robustness and accuracy of models for predicting blood glucose concentrations. Therefore, an improved signal reconstruction and calibration modeling method is proposed in this study. On the basis of improved complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and correlative coefficient, the sensitive intrinsic mode functions are selected to reconstruct spectroscopy signals for developing the calibration model using the support vector regression (SVR) method. The radial basis function kernel is selected for SVR, and three parameters, namely, insensitive loss coefficient ε, penalty parameter C, and width coefficient γ, are identified beforehand for the corresponding model. Particle swarm optimization (PSO) is employed to optimize the simultaneous selection of the three parameters. Results of the comparison experiments using PSO-SVR and partial least squares show that the proposed signal reconstitution method is feasible and can eliminate noise in spectroscopy signals. The prediction accuracy of model using PSO-SVR method is also found to be better than that of other methods for near-infrared noninvasive glucose detection.
糖尿病是对人类健康的严重威胁。因此,无创血糖检测的研究在国内外都变得至关重要。近红外透射光谱在无创血糖检测中具有重要应用。提取有用信息并选择合适的建模方法可以提高血糖浓度预测模型的稳健性和准确性。因此,本研究提出了一种改进的信号重构和校准建模方法。基于改进的自适应噪声总体平均经验模态分解(CEEMDAN)和相关系数,选择敏感的本征模态函数来重构光谱信号,以便使用支持向量回归(SVR)方法建立校准模型。为SVR选择径向基函数核,并预先确定相应模型的三个参数,即不敏感损失系数ε、惩罚参数C和宽度系数γ。采用粒子群优化(PSO)来优化这三个参数的同时选择。使用PSO-SVR和偏最小二乘法的对比实验结果表明,所提出的信号重构方法是可行的,并且可以消除光谱信号中的噪声。还发现使用PSO-SVR方法的模型对于近红外无创血糖检测的预测准确性优于其他方法。