Abstract The ion sensor(ion selectivity electrode) is one of the key technologies in the water quality monitoring, wastewater treatment and factory agriculture. The nonlinearity, drift and intercross sensitivity of the ion sensor impact on the accuracy and reliability obviously, therefore, it is difficult for majority of the ion sensors to continuously detect in situ. In order to detect dynamic environment on line, selfcalibration of the ion sensor is investigated and its response properties are analyzed in terms of the experimental data. The zero and time drift are taken into account, and a selfcalibration of ion sensor is proposed based on least squares support vector machines (LSSVM). The experimental results show response error of the ion sensor is decreased obviously and this approach is practical.
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2007, Vol. 20 
