A Development of Supply Performance Indicator in a Water Distribution System Using Fuzzy Sets and a PDA Model

Abstract

The water distribution system is an infrastructure system supplying water to urban areas. Since it has a great influence on the quality of life and financial aspect of customers, the performance evaluation of the system for an efficient management and operation is essential. Until now, most of the suggested performance indicators for the system are based on the available demand and pressure at demand nodes obtained from the hydraulic simulation. However, those performance indicators based on the hydraulic simulation may not consider the actual usability of water for customers properly. Therefore, in this study, the application of fuzzy functions along with the available demands at demand nodes, which are obtained from the hydraulic simulation, from the various points of view, makes us possible to evaluate the system performance by depending on the set value of the variables. For this purpose, we use a PDA model, which can simulate various abnormal operation conditions and suggest two performance indicators: the possible water supply range indicator (PWSRI) for the water supply performance evaluation for an individual demand node and the possible water supply indicator for the entire system (PWSIES). The suggested method and indicators are applied to the real water distribution system of A-city in Korea to verify the applicability.

Development of a Fuzzy-Function-Based Performance Indicator for Water Distribution System’s Emergency Condition

“…Fuzzy set theory can be used to classify objects with a membership function while compensating for errors in the existing dichotomous framework of thinking. This is a new form of artificial intelligence theory where human language is expressed with a computer, and objects are assessed similarly to how humans think [18,19]. If a membership function is defined as having a value between 0 and 1, the membership status of partially true or partially false can be expressed, and the corresponding value represents the corresponding object.…”

“…In this study, the fuzzy membership performance measure (FMPM) was developed to indicate the consumer satisfaction level with the water availability. In order to reflect time-varying consumer satisfaction, a fuzzy large membership function is used [18]. FMPM can be used to assess the satisfaction level with the available supply for each individual node in a WDS:…”