flink learn demo implement the feature extract model in 「 N. Yan, T. Lin, Y. Zheng and Z. Xu, "Combining Periodic Feature and Behavioral Transfer With Ensemble of Models for MOOCs Dropout Prediction," 2021 IEEE International Conference on Engineering, Technology & Education (TALE), 2021, pp. 1-6, doi: 10.1109/TALE52509.2021.9678819. 」