Use of multi-functional sensing for the measurement of electrolytic concentration in solution with higher accuracy

In this paper, a noncontact multifunctional sensing technique is investigated for the measurement of low concentration of electrolyte in aqueous solution with higher accuracy. With the experimental data of a practically designed multi-functional sensor, the improvement is statistically analyzed. Primary estimations of the concentration are obtained by mathematically modeling the sensor responses in its inductive and capacitive sensing functions. The final estimation of the concentration combining the two mean of the primarily estimated concentration with two optimum weights on each mean is proposed. With the experimental data of K/sub 2/SO/sub 4/ solution, a considerable improvement in the variance of the finally estimated concentration was obtained.