SURFACE WATER QUALITY ASSESSMENT BY USE OF A COMBINATION OF PROJECTION PURSUIT AND PRINCIPAL COMPONENT ANALYSIS

摘要

Considering that there are still some limits of present comprehensive evaluation methods for surface water quality assessment, in this paper, an improved method (PPM-PCAM) which combines projection pursuit model (PPM) with principal component analysis method (PCAM) was developed for use. Within this method, the projection index function in the projection pursuit model was optimized by applying PCAM, and the objective weight, adopted to deal with the special influence of data to a maximum extent, can effectively avoid the artificial influence factor. Moreover, the existing water quality samples of Emei river in China are taken for a case study, and the comparisons with other methods show that the developed method is superior for assessing the surface water quality levels. Furthermore, the developed method is shown to be of a high accuracy. Overall, it is an effective method, and can be applied to evaluate the surface water quality status.