A new method for mathematical modelling of complex stage–discharge relations

Abstract

This paper describes a computer-based approach named multiobjective stage–discharge evaluator (MOSDE), which employs the method of regression analysis for the development of stage–discharge rating curves. The regression is done recursively as the program steps through the data set, by adding one point at each iteration. Multiobjective analysis is used to evaluate the improvement or deterioration of the model using a set of statistical criteria. The overall task is to fit a proper curve, or curves, to any given stage–discharge data set. Also, the key transition points in the stage–discharge relation are identified. This process eliminates ambiguity or subjectivity associated with the current methods used for the development of stage–discharge relationships. The MOSDE system has been tested using two different data sets. Key words: operational hydrology, stage–discharge, multiobjective analysis, mathematical modelling.