Improved model of the retardance in citric acid coated ferrofluids using stepwise regression

5th International Conference on Manufacturing, Optimization, Industrial and Material Engineering

Lin, J.F.^1 ; Qiu, X.R.^2

Department of Industrial Design, Far East University, No. 49, Zhonghua Rd., Xinshi Dist., Tainan City

74448, Taiwan^1

Graduate School of Mechanical Engineering, Far East University, No. 49, Zhonghua Rd., Xinshi Dist., Tainan City

74448, Taiwan^2

关键词: Average absolute error;    Biomedical applications;    Coating temperature;    Correlation coefficient;    Multiple regressions;    Stepwise regression;    Stepwise regression method;    Stokes polarimeter;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/215/1/012003/pdf
DOI  :  10.1088/1757-899X/215/1/012003

来源: IOP

【 摘 要 】

Citric acid (CA) coated Fe3O4ferrofluids (FFs) have been conducted for biomedical application. The magneto-optical retardance of CA coated FFs was measured by a Stokes polarimeter. Optimization and multiple regression of retardance in FFs were executed by Taguchi method and Microsoft Excel previously, and the F value of regression model was large enough. However, the model executed by Excel was not systematic. Instead we adopted the stepwise regression to model the retardance of CA coated FFs. From the results of stepwise regression by MATLAB, the developed model had highly predictable ability owing to F of 2.55897e+7 and correlation coefficient of one. The average absolute error of predicted retardances to measured retardances was just 0.0044%. Using the genetic algorithm (GA) in MATLAB, the optimized parametric combination was determined as [4.709 0.12 39.998 70.006] corresponding to the pH of suspension, molar ratio of CA to Fe3O4, CA volume, and coating temperature. The maximum retardance was found as 31.712°, close to that obtained by evolutionary solver in Excel and a relative error of -0.013%. Above all, the stepwise regression method was successfully used to model the retardance of CA coated FFs, and the maximum global retardance was determined by the use of GA.