Abstract
A binocular stereovision system has been developed to estimate growth variables of a transplant population. In the present study, the image analysis system was improved by adopting a three-layered artificial neural network model (ANN model) based on a back-propagation algorithm. Inputs of the ANN model were average height, leaf area, projected leaf area, and mass volume of the transplant population obtained from the image analysis system. Outputs of the ANN model were average height, number of unfolded leaves, leaf area, and fresh and dry masses of the transplant population, which give a more accurate assessment of the transplant growth status than that obtained from the image analysis system. The number of nodes in the hidden layer of the ANN model was determined through trial and error. The growth variables thus obtained from the ANN model using a sweetpotato (Ipomoea batatas (L.) Lam.) transplant population were more accurate than those obtained from a regression model. The image analysis system, after being improved by using the ANN model, successfully identified the transplant growth status with a high degree of accuracy.
