Evaluating polynomial and Gaussian fitting techniques for accurate sub-index pH modeling in water quality index development

Abstract This study proposes and evaluates curve-fitting models—specifically polynomial and Gaussian techniques—to accurately compute the pH sub-index as part of a Water Quality Index (WQI). This modeling is essential for enhancing the reliability of pH representation in real-time Internet of Things...

Full description

Saved in:
Bibliographic Details
Main Authors: Wibowo Harry Sugiharto, Agung Budi Prasetijo, Heru Susanto
Format: Article
Language:English
Published: Springer 2025-07-01
Series:Discover Water
Subjects:
Online Access:https://doi.org/10.1007/s43832-025-00246-6
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract This study proposes and evaluates curve-fitting models—specifically polynomial and Gaussian techniques—to accurately compute the pH sub-index as part of a Water Quality Index (WQI). This modeling is essential for enhancing the reliability of pH representation in real-time Internet of Things (IoT)-based water quality monitoring systems. By improving the pH sub-index formulation, the research aims to address one of the core components in WQI computations under dynamic environmental conditions. This work represents a critical step in the second phase of developing the IoT-based Water Quality Index (IoTWQI) framework. The resulting models are validated and compared for their suitability in sensor-based environments. The findings highlight the Gaussian Model 1 as the most accurate choice for normally distributed data (RMSE = 2.15), whereas the 6th-degree Polynomial Model remains effective in capturing complex nonlinear variations (RMSE = 4.26). These insights contribute directly to improving real-time WQI calculation performance in IoT ecosystems.
ISSN:2730-647X