On-Site/In Situ Continuous Detecting ppb-Level Metal Ions in Drinking Water Using Block Loop-Gap Resonators and Machine Learning. - Sangmin Oh; Imtiaz Hossen; Juan Luglio; Gusphyl A. Justin; James E. Richie; Henry Medeiros 001; Chung Hoon Lee (IEEE Trans. Instrum. Meas., 2021)