研究目的
To evaluate the efficiency of different band selection methods for PLS regression models in estimating leaf biochemical contents from hyperspectral reflectance, specifically focusing on their ability to locate physiochemical mechanism-based informative bands.
研究成果
PLS regression models can efficiently estimate leaf biochemical contents, but the selected bands often do not match known absorption features, reducing robustness. The GA-PLS method is more effective at locating mechanism-based informative bands compared to stepwise-PLS and UVE-PLS, making it recommended for future applications. Collinearity among reflectance bands is a key factor influencing band selection.
研究不足
The study is based on simulated data from a modified PROSPECT-4 model, which may not fully capture real-world complexities; the dummy variable approach simplifies actual biochemical interactions; collinearity among reflectance bands poses challenges for band selection methods; the GA-PLS method, while better, still does not always converge to optimal solutions.
1:Experimental Design and Method Selection:
The study used a modified PROSPECT-4 leaf reflectance model by introducing a dummy variable (Cd) with specific absorption coefficients (SAC) to simulate hyperspectral reflectance data. Three band selection techniques (stepwise-PLS, GA-PLS, UVE-PLS) were applied to PLS regression models.
2:Sample Selection and Data Sources:
Virtual datasets were generated using the modified PROSPECT-4 model with parameters based on the Leaf Optical Properties Experiment (LOPEX) database, including 500 simulated leaf reflectance spectra per combination of SAC parameters (peak location, intensity, half-width).
3:List of Experimental Equipment and Materials:
The PROSPECT-4 model was used for simulation; no physical equipment is mentioned.
4:Experimental Procedures and Operational Workflow:
SACs for Cd were generated using Gaussian functions; reflectance spectra were simulated between 400-800 nm at 5 nm resolution; PLS models were calibrated and validated using the simulated data with the three band selection methods.
5:Data Analysis Methods:
Statistical criteria (NRMSE, R2, AICc) were used to evaluate model performance; correlation analyses were conducted to assess collinearity among bands.
独家科研数据包,助您复现前沿成果,加速创新突破
获取完整内容