Research on density-independent arithmetic for measuring moisture of cereal with microwave

Microwave techniques are suitable for real-time monitoring and control. However, when using in cereal moisture determination, bulk density fluctuations cause significant errors. The density-independent function that is limited to transmission techniques was obtained by experience, and has been widely used in many papers. A function, which interrelates with the cereal´s dielectric properties, is identified, and regression equations of moisture are given. The calibration function of moisture and bulk density is presented based on the new density-independent function. Experiment shows the good performance of the arithmetic with determination coefficient and the mean squared error are 0.985 and 0.019 respectively.