Relative Humidity Estimation Based on Two Nested Kalman Filters with Bicubic Interpolation for Commercial Cultivation of Tropical Orchids. - Nutchanon Siripool; Kraithep Sirisanwannakul; Waree Kongprawechnon; Prachumpong Dangsakul; Anuchit Leelayuttho; Sommai Chokrung; Jakkaphob Intha; Suthum Keerativittayanun; Jessada Karnjana (IUKM, 2020)