Reliability, resilience, and vulnerability (RRV) have been widely used as the performance criteria of a water supply system in the studies conducted over the last three decades. This study attempts to modify the traditional method commonly applied to estimate these criteria using fuzzy logic thereby the performance criteria of the points with the threshold and intermediate values are more accurately estimated. Traditional methods (RRV-Fixed) of estimating these criteria are based on the fixed threshold values to represent the functionality of a water supply system, using a binary system to identify the periods a system fails to supply the water demands. The employment of this binary system may be taken into account as a weakness of the evaluating system, especially when water portion met is close to the threshold values. The present study develops a new method named RRV-Fuzzy, to ameliorate the weaknesses of the traditional RRV-Fixed estimating system.The method is designated as “Fuzzy Performance Criteria” built upon the traditional RRV formulae with improvements made to their structures using fuzzy membership functions. The efficiency of the proposed method is verified via implementation on two case studies including a theoretical and a real-world water basin. A comparison of the proposed RRV-Fuzzy and the traditional RRV-Fixed methods confirms the efficiency of the proposed method with regard to the improvements achieved in the relevant estimations, validating the new approach to be quite effective and practicable.

在过去的三十年中，可靠性，弹性和脆弱性（RRV）被广泛用作供水系统的性能标准。本研究试图修改使用模糊逻辑估算这些标准的传统方法，从而更准确地估算具有阈值和中间值的点的性能标准。估计这些标准的传统方法（RRV固定）基于固定阈值来表示供水系统的功能，使用二进制系统来识别系统无法满足用水需求的时间段。该二元系统的使用可以被视为评估系统的弱点，尤其是当所满足的水量接近阈值时。“模糊性能标准”以传统的RRV公式为基础，并使用模糊隶属函数对其结构进行了改进。通过在两个案例研究（包括理论流域和实际流域）上的实施验证了所提方法的效率。将拟议的RRV-Fuzzy方法与传统的RRV-固定方法进行比较，可以证实所提方法相对于相关估计所实现的改进是有效的，从而验证了新方法的有效性和实用性。