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The exponential development of expressways has resulted in increased demand for highway electromechanical (E&M) equipment. However, the constant changes in parameters and models of electromechanical equipment make national quotas outdated and complicate price forecasting due to data collection challenges and significant price variability. To address this, the study introduces the coefficient of variation (CV) to reduce variability. Therefore, this study further introduces a novel hybrid forecasting model for the CV of E&M equipment pricing and proposes a coefficient analysis and prediction system based on particle swarm optimization (PSO) and XGBoost to analyze the driving factors behind the price fluctuations of highway E&M equipment which aims to provide a scientific and rational reference for the pricing of E&M equipment. The evaluation metrics is R² = 0.90066, MAE = 0.033412, MAPE = 11.5624 %, MSE = 0.0017948, and RMSE = 0.045769, showed that the PSO–XGBoost model outperformed the other models in terms of precision and stability in prediction, demonstrating the proposed model's effectiveness in forecasting CVs for E&M equipment pricing and demonstrating the feasibility of the model to elucidate the factors influencing price changes.

4,4-Difluoro-4-bora-3a,4a-diaza-sindacene (BODIPY) is a sort of photofunctional dye which possesses advantages including strong light-capturing property, high photon-resistance, etc. Meso-N substituted aza-BODIPY is a crucial derivative of BODIPY scaffold that has the favorable optical properties and a significant spectral redshift. The photophysical properties can be tuned by molecular design, and the attenuation path of the excited state energy release of absorbed light energy can be well controlled via structural modifications, enabling tailored application. It has been extensively employed in life medicine fields including fluorescence imaging diagnosis, photodynamic therapy photosensitizer and photothermal therapy reagent and so forth. Extensive research and review have been performed in these areas. However, BODIPYs/aza-BODIPYs have a significant role in energy, catalysis, optoelectronics, photo-responsive materials and other fields. Nevertheless, there are relatively few studies and reviews in these fields on the modification and application based on BODIPY/aza-BODIPY scaffold. Herein, in this review we summarized the application of BODIPY/aza-BODIPY in the aforementioned fields, with the molecular regulation of dye as the foundation and the utilization in the above fields as the objective, in the intention of providing inspiration for the exploration of innovative BODIPY/aza-BODIPY research in the field of light resource conversion and functional materials.