Energy-loss measurements of direct-excitation and electron-capture processes are performed for the He+-N"-G, collisional systems in the 0.2~keV energy range and in the 0'-3 angular range. Pure vibrational excitation and vibrational excitation in excited electronic states are studied using a high-resolution spectrometer (100 meV). Pure vibrational excitation is always found to be a weak process. The analysis qf vibrational distributions in excited states strongly supports an interpretation in terms of the Franck-Condon principle. Relative probabilities as functions of energy and angle are reported for the identified excitation and electron-capture processes. The results show the importance of electron-capture processes among which quasiresonant and endothermic processes dominate exothermic processes. The striking resemblance of the present data with those available on the He+-rare-gas systems conveys a similar quasimolecular interpretation of the collision mechanisms. 2445

Phosphate is one of the major elements affecting agricultural production. The accurate determination of phosphate concentration essential for plant growth, especially in a hydroponics system, allows regulating the balanced and suitable range set of nutrients to plants efficiently. This study proposed a data fusion model based on 70 samples for calibration and 30 samples for predicting concentrations of phosphate in an eggplant nutrient solution. Three multivariate analysis methods i.e. partial least squares model (PLS), Gaussian process regression (GPR), and artificial neural network (ANN) were studied and compared for their performance efficiencies. The results showed that combining the multivariate standard addition method (MSAM) in acquiring data from cobalt electrodes and ANN data fusion model came up with satisfactory outcomes. Both the method provided good performance with R 2 values of 0.98 and 0.96, and the root mean square error (RMSE) of 50 and 66 mg. L −1 respectively in calibration and evaluation tests. These values were much higher than those of conventional processing techniques. Moreover, the normal direct calibration method in acquisition signal from cobalt electrodes was also applied, which provided R 2 values of 0.7 to 0.8. These high values are sufficient for development to measure phosphate concentration in hydroponic solutions. INDEX TERMS Phosphate sensing, multi-sensor data fusion, multivariate standard addition method (MSAM), partial least squares model (PLS), Gaussian process regression (GPR), neural network-ANN.