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Floods, one of the most common natural hazards globally, are challenging to anticipate and estimate accurately. This study aims to demonstrate the predictive ability of four ensemble algorithms for assessing flood risk. Bagging ensemble (BE), logistic model tree (LT), kernel support vector machine (k-SVM), and k-nearest neighbour (KNN) are the four algorithms used in this study for flood zoning in Jeddah City, Saudi Arabia. The 141 flood locations have been identified in the research area based on the interpretation of aerial photos, historical data, Google Earth, and field surveys. For this purpose, 14 continuous factors and different categorical are identified to examine their effect on flooding in the study area. The dependency analysis (DA) was used to analyse the strength of the predictors. The study comprises two different input variables combination (C1 and C2) based on the features sensitivity selection. The under-the-receiver operating characteristic curve (AUC) and root mean square error (RMSE) were utilised to determine the accuracy of a good forecast. The validation findings showed that BE-C1 performed best in terms of precision, accuracy, AUC, and specificity, as well as the lowest error (RMSE). The performance skills of the overall models proved reliable with a range of AUC (89–97%). The study can also be beneficial in flash flood forecasts and warning activity developed by the Jeddah flood disaster in Saudi Arabia. [ABSTRACT FROM AUTHOR]

Background: Hormone production by the thyroid gland is a prime aspect of maintaining body homeostasis. In this study, the ability of single artificial intelligence (AI)-based models, namely multi-layer perceptron (MLP), support vector machine (SVM), and Hammerstein–Weiner (HW) models, were used in the simulation of thyroidism status. The study's primary aim is to unveil the best performing model for the simulation of thyroidism status using hepatic enzymes and hormones as the independent variables. Three statistical metrics were used in evaluating the performance of the models, namely determination coefficient (R2), correlation coefficient (R), and mean squared error (MSE). Results: Considering the quantitative and visual presentation of the results obtained, it has been observed that the MLP model showed higher performance skills than SVM and HW, which improved their performances up to 3.77% and 12.54%, respectively, in the testing stages. Furthermore, to boost the performance of the single AI-based models, three different ensemble approaches were employed, including neural network ensemble (NNE), weighted average ensemble (WAE), and simple average ensemble (SAE). The quantitative predictive performance of the NNE technique boosts the performance of SAE and WAE approaches up to 2.85% and 1.22%, respectively, in the testing stage. Conclusions: Comparative performance of the ensemble techniques over the single models showed that NNE outperformed all the three AI-based models (MLP, SVM, and HW) and boosted their performance accuracy up to 7.44%, 11.212%, and 19.98%, respectively, in the testing stages. [ABSTRACT FROM AUTHOR]

This study aimed at employing three data-driven models, namely the Hammerstein-Weiner (HW) model, support vector machine (SVM), and feedforward back propagation neural network (FFBPNN) and traditional multi-linear regression, as well as two non-linear ensemble techniques viz: HW-ensemble and FFBPNN-ensemble, were employed to predict chemical oxygen demand (CODeff). For the prediction of the CODeff, two types of data were used, the first one being environmental data from the new Nicosia waste water treatment plant conductivity (Condinf), including total nitrogen (TNinf), total phosphorus (TPinf) and one-effluent parameter CODeff as M1, where the second was meteorology data from the National Aeronautics and Space Administration (NASA) (at 2 m above the Earth's surface), such as relative humidity (R2H), maximum temperature (T2M_M) and mean temperature (T2M) as M2, in a hybrid model M3, which was a combination of both the meteorology and environmental data M1 and M2. According to the performance criteria RMSE and DC of the single models, values of HW-M1 (0.0308 and 0.9686), HW-M2 (0.0322 and 0.9093) and SVM-M3 (0.025 and 0.9486) were recorded. The ensemble technique improved the performance of the single models in the verification phase by 12% and 19% for HW-E and FFBPNN-E, respectively. [ABSTRACT FROM AUTHOR]

One of the most challenging tasks in rainfall prediction is designing a reliable computational methodology owing the random and stochastic characteristics of time-series. In this study, the potential of five different data-driven models including Multilayer Perceptron (MLP), Least Square Support Vector Machine (LSSVM), Neuro-fuzzy, Hammerstein-Weiner (HW) and Autoregressive Integrated Moving Average (ARIMA) were employed for multi-station (Hien, Thank My, Hoi Khanh, Ai Nghia and Cai Lau) prediction of daily rainfall in the Vu Gia-Thu Bon River basin in Central Vietnam. Subsequently, hybrid ARIMA-MLP, ARIMA-LSSVM, ARIMA-NF and ARIMA-HW models were also utilized to predict the daily rainfall at these stations. The results were evaluated in terms of widely used performance criteria, viz.: determination coefficient (R2), root mean square error (RMSE), mean absolute error (MAE) and correlation coefficient (CC). Besides, the Taylor diagram is also used to examine and compare the similarity between the observed and predicted rainfall. The quantitative analysis indicated that the HW model increased the prediction accuracy by 5%, 3% and 2% at Hien, Ai Nghia and Cau Lau stations, respectively, compared to the other models. Likewise, the NF model increased the prediction accuracy at Thanh My and Hoi Khanh stations in contrast to the other models in terms of the mean absolute error. Also, the results of hybrid ARIMA-NF and ARIMA-HW models showed the best performance in terms of predictive skills and verified to increase the prediction accuracy in comparison to the single models. [ABSTRACT FROM AUTHOR]

In the present study, three different artificial intelligence based non-linear models, i.e. feed forward neural network (FFNN), adaptive neuro fuzzy inference system (ANFIS), support vector machine (SVM) approaches and a classical multi-linear regression (MLR) method were applied for predicting the performance of Nicosia wastewater treatment plant (NWWTP), in terms of effluent biological oxygen demand (BODeff), chemical oxygen demand (CODeff) and total nitrogen (TNeff). The daily data were used to develop single and ensemble models to improve the prediction ability of the methods. The obtained results of single models proved that, ANFIS model provides effective outcomes in comparison with single models. In the ensemble modeling, simple averaging ensemble, weighted averaging ensemble and neural network ensemble techniques were proposed subsequently to improve the performance of the single models. The results showed that in prediction of BODeff, the ensemble models of simple averaging ensemble (SAE), weighted averaging ensemble (WAE) and neural network ensemble (NNE), increased the performance efficiency of artificial intelligence (AI) modeling up to 14%, 20% and 24% at verification phase, respectively, and less than or equal to 5% for both CODeff and TNeff in calibration phase. This shows that NNE model is more robust and reliable ensemble method for predicting the NWWTP performance due to its non-linear averaging kernel. [ABSTRACT FROM AUTHOR]

In this study, two different single non-linear [feedforward neural network (FFNN) and support vector machine (SVM)] models with a traditional linear regression model [multi-linear regression (MLR)] were employed to predict the qualitative behaviour of thymoquinone (TQ) in HPLC method development interms of retention properties. The simulation involves the use of the concentration of the standard, the mobile phase, pH and flow rate as the corresponding input variables, while the retention time (tR) of TQ is considered as the dependent variable. Four performance indices were employed to determine the accuracy of the models, namely correlation coefficient (R), root mean square error (RMSE), mean square error (MSE) and determination coefficient (R2). Subsequently, hybrid models were proposed for the prediction of the bioactive compound in HPLC method development, which combines the AI-based models and the classical MLR (i.e FFNN-MLR and SVM-MLR) to enjoy the benefits of the linear and non-linear properties of the models. The results obtained based on the predictive comparison of the single models showed that FFNN outperformed the other two models. Further elucidation of the results showed that the hybrid models FFNN-MLR and SVM-MLR demonstrated higher performance in terms of the performance indices and they are all capable of boosting the performance efficiency of the single models up to 12%. [ABSTRACT FROM AUTHOR]