Application of varying coefficient discrepancy degree in
water quality evaluation of water supply networks
Abstract
Set pair analysis (SPA) is a new method to describe and process the system uncertainty and has been applied in many
areas recently. In view of the uncertainty and complexity in the process of water quality evaluation of water supply
networks, the paper introduced a new model-varying coefficient of discrepancy degree based on set pair analysis
theory. In the model, a new effective method to the determination of discrepancy degree coefficient i is suggested.
As an example, the paper evaluated water quality conditions of water supply networks from 3 monitoring spots by the
model. The results of the assessment are in concordance with other evaluation methods. Compared with the other
evaluation method, this model is perfect, the evaluating result is more reasonable and its resolving power is higher.
1. Introduction
The water supply network due to the increasing use of water quality deterioration, brings many
problems affecting normal water supply, evaluating the quality of drinking water from the treatment plant
to the consumers tap is critical to ensure compliance with national standards [1]. The water evaluation for
water supply network is helpful to find out the water quality current status and puts forward the
corresponding countermeasures to the protection of water sources. Consequently, the water quality
evaluation for water supply network is popularly applied at home and abroad [2].The comprehensive
evaluation of water quality for water supply network is an all-round system recognition and judgment.
Evaluation systems usually have multi-grades involving multi-factors, with complex nonlinear relations
between inter-related and interrestricted evaluation factors and grades, leading to the uncertainty of the
evaluation systems. With
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