Papers by Mehdi Fuladipanah
Water practice and technology, Jun 3, 2024
Results in engineering, Jun 1, 2024
Water supply, Feb 1, 2024
Applied Water Science, Nov 6, 2023
The study focuses on the critical concern of designing secure and resilient bridge piers, especia... more The study focuses on the critical concern of designing secure and resilient bridge piers, especially regarding scour phenomena. Traditional equations for estimating scour depth are limited, often leading to inaccuracies. To address these shortcomings, modern data-driven models (DDMs) have emerged. This research conducts a comprehensive comparison involving DDMs, including support vector machine (SVM), gene expression programming (GEP), multilayer perceptron (MLP), gradient boosting trees (GBT) and multivariate adaptive regression spline (MARS) models, against two regression equations for predicting scour depth around cylindrical bridge piers. Evaluation employs statistical indices, such as root-mean-square error (RMSE), coefficient of determination (R 2), mean average error (MAE) and normalized discrepancy ratio (S (DDRmax)), to assess their predictive performance. A total of 455 datasets from previous research papers are employed for assessment. Dimensionless parameters Froude number � Fr = U √ gy � , Pier Froude number Fr P = U √ g � D , and the ratio of scour depth to pier diameter (y D) are carefully selected as influential model inputs through dimensional analysis and the gamma test. The results highlight the superior performance of the SVM model. In the training phase, it exhibits an RMSE of 0.1009, MAE of 0.0726, R 2 of 0.9401, and S DDR of 2.9237. During testing, the SVM model shows an RMSE of 0.023, MAE of 0.017, R 2 of 0.984, and S DDR of 5.301. Additionally, it has an average error of − 0.065 and a total error of − 20.642 in the training set and an average error of − 0.005 and a total error of − 0.707 in the testing set. Conversely, the M5 model exhibits the lowest accuracy. The statistical metrics unequivocally establish the SVM model as significantly outperforming the experimental models, placing it in a higher echelon of predictive accuracy.
Background: River flow estimation has important role in water resources management. SRM is a hydr... more Background: River flow estimation has important role in water resources management. SRM is a hydrologic model which has been used widely to estimate river flow in mountain catchment which snow and snowmelt have significant role in water supply of rivers. Objective: The model has ten input variables. Each variable has different relation with model output. Determination of significant variables will increase model output reliability. In this paper, two approaches were applied to determine the sensitivity level of SRM inputs on its output: Fourier Amplitude Sensitivity Test which is based on variance analysis, and Scatter Plot method. Results: High three Sensitivity indices of FAST method were calculated for discharge of before day, Q as 0.26, catchment area, A as 0.18, and percent of snow cover of catchment, S as 0.15. Minimum sensitivity index was calculated for temperature gradient. Conclusion: The most and the least variation of model output were plotted for the discharge of the day before and the temperature gradient based on scatter plot, respectively. On the other words, the results of two methods are unique.
Abstract: The analysis of energy dissipation rate plays a major role in the problem of inclined s... more Abstract: The analysis of energy dissipation rate plays a major role in the problem of inclined stepped spillways. In this paper, the derivation of relative energy dissipation equation on adverse-slopped stepped spillways has been considered. Step length (L), step height (h), the adverse-slope of step (), ratio yc h ( ) , ratio () h L and energy dissipation rate for each step ( ) were used to derive the equation. Using Bukingham pi theorem and dimensional analysis, five dimensionless parameters in the form of a dimensionless function was derived. The multiple linear regression (using SPSS software) was used to calculate unknown coefficients of the equation. The equation was applied to simulate relative energy dissipation. The results by predictions were in
In this paper, two groups of datasets including Froehlich (1988) and USGS were implemented to sim... more In this paper, two groups of datasets including Froehlich (1988) and USGS were implemented to simulate scour depth for bridge piers of three shapes (circular, sharp-nose and rectangular) using support vector machine (SVM) algorithm. The results of the SVM were compared with gene expression programming (GEP) and the non-linear regression model. Independent parameters extracted using dimensional analysis were Froud number (Fr), the ratio of pier length to pier width (L/b), the ratio of sediment particle diameters (d50/d84), the ratio of sediment mean size to pier width (d50/b) and attack angle of water flow (α). Different combinations of independent variables were used to achieve optimum performance of the simulator. The results showed that among three simulators, the SVM algorithm had the best performance to predict local scour depth. The sensitivity analysis revealed that among independent parameters, the descending order of effectivity was Fr, sediment size, L/b, and α.
Siphon spillways are hydraulic structures which can pass surplus storm water automatically. Hence... more Siphon spillways are hydraulic structures which can pass surplus storm water automatically. Hence their stability has more importance. The reliable predictor derived physical modeling have significant role in this case. Different types of equations can be derived using statistical methods which each type has its applied limitations. This paper has been attempted to derive non-linear equations to predict scour hole dimensions downstream siphon spillway. Scour hole dimesions as: d (the maximum depth of scour hole), l s 2 (upstream hill distance from the bucket), h (height of upstream hill) and h (height of downstream hill) were u d investigated through this research work. Using Bukingham pi theorem, three dimensionless parameters were derived as . Each scour hole dimension was related to mentioned dimensionless parameters using multiple linear regression technique. The results of physical modeling and simulation values were compared using statics indices. The results of predictions ha...
Water science and engineering, 2018
The water crisis in arid and semi-arid areas causes more integrated studies regarding the utiliza... more The water crisis in arid and semi-arid areas causes more integrated studies regarding the utilization of urban wastewater. In this research, the analytic hierarchy process was conducted in 2014 according to the relative weight of criteria resulted from a questionnaire and a primary normal matrix. The results showed that the criteria including the quality of wastewater and benefit per cost were the most restrictive criteria that have the highest relative weight percentage as much as 22 and 21.5%, respectively. The other criteria were the public acceptance, government’s supportive policies potential of the area, and distance of feeding area with the water treatment plant with a percentage as much as 20.2, 14.6, 11.5, and 10.4%, respectively. The agricultural lands irrigation with the highest rank as much as 27.5% was preferred, which indicates that the use of Arak urban wastewater should be prioritized for agricultural irrigation. The second alternative is related to the rehabilitatio...
Sensitivity analysis as a technique is applied to determine influential input factors on model ou... more Sensitivity analysis as a technique is applied to determine influential input factors on model output. Variance-based sensitivity analysis method has more application compared to other methods because of including linear and non-linear models. In this paper, van Rijn"s movable bed roughness formula was selected to evaluation because of its reasonable results in sandy rivers. This equation contains four variables as: flow depth, sediment size, Bed form height and Bed form length. These variable"s importance was determined using the first order of Fourier Amplitude Sensitivity Test. Sensitivity index was applied to evaluate importance of factors. The first order FAST based sensitivity indices test, explain 90% of the total variance that is indicating acceptance criteria of FAST application. More value of this index is indicating more important variable. Results show that bed form height, bed form length, sediment size and flow depth are more influential factors with sensitiv...
Background: River flow estimation has important role in water resources management. SRM is a hydr... more Background: River flow estimation has important role in water resources management. SRM is a hydrologic model which has been used widely to estimate river flow in mountain catchment which snow and snowmelt have significant role in water supply of rivers. Objective: The model has ten input variables. Each variable has different relation with model output. Determination of significant variables will increase model output reliability. In this paper, two approaches were applied to determine the sensitivity level of SRM inputs on its output: Fourier Amplitude Sensitivity Test which is based on variance analysis, and Scatter Plot method. Results: High three Sensitivity indices of FAST method were calculated for discharge of before day, Q as 0.26, catchment area, A as 0.18, and percent of snow cover of catchment, S as 0.15. Minimum sensitivity index was calculated for temperature gradient. Conclusion: The most and the least variation of model output were plotted for the discharge of the day before and the temperature gradient based on scatter plot, respectively. On the other words, the results of two methods are unique.
Absract: Infiltration process is one of the most natural phenomena which plays significant role i... more Absract: Infiltration process is one of the most natural phenomena which plays significant role in engineering problems. It is very important to determine an appropriate model to predict infiltration process. There are different equations to simulate infiltration process. In this paper Kostiakov, Philip and SCS models were tested to select fitted one for Shazand plane, Arak, Iran. Double ring test was done in Shazand plane to determine mentioned models parameters. RMSE and N.S. indices were used to calculate accuracy of simulation. RMSE and N.S. were calculated for Kostiakov, Philip and SCS as following: (0.1933, 0.992197), (0.1011, 0.995919), (0.0688, 0.99722), respectively. Therefore, SCS model was selected as appropriate one to simulate infiltration process.
JWSS - Isfahan University of Technology, 2021
Water Supply, 2021
As a remarkable parameter, the discharge coefficient (Cd) plays an important role in determining ... more As a remarkable parameter, the discharge coefficient (Cd) plays an important role in determining weirs' passing capacity. In this research work, the support vector machine (SVM) and the gene expression programming (GEP) algorithms were assessed to predict Cd of piano key weir (PKW), rectangular labyrinth weir (RLW), and trapezoidal labyrinth weir (TLW) with gathered experimental data set. Using dimensional analysis, various combinations of hydraulic and geometric non-dimensional parameters were extracted to perform simulation. The superior model for the SVM and the GEP predictor for PKW, RLW, and TLW included , and respectively. The results showed that both algorithms are potential in predicting discharge coefficient, but the coefficient of determination (RMSE, R2, Cd(DDR)max) illustrated the superiority of the GEP performance over the SVM. The results of the sensitivity analysis determined the highest effective parameters for PKW, RLW, and TLW in predicting discharge coefficien...
علوم آب و خاک, Feb 1, 2021
Abstract: Siphon spillways are hydraulic structures which can pass surplus storm water automatica... more Abstract: Siphon spillways are hydraulic structures which can pass surplus storm water automatically. Hence their stability has more importance. The reliable predictor derived physical modeling have significant role in this case. Different types of equations can be derived using statistical methods which each type has its applied limitations. This paper has been attempted to derive non-linear equations to predict scour hole dimensions downstream siphon spillway. Scour hole dimesions as: d s(the maximum depth of scour hole), l2 (upstream hill distance from the bucket), h u (height of upstream hill) and h d (height of downstream hill) were investigated through this research work. Using Bukingham pi theorem, three dimensionless parameters were derived as d50 Q ht h
Water flow management is one of the most important<br> parts of river engineering. Non-unif... more Water flow management is one of the most important<br> parts of river engineering. Non-uniformity distribution of rainfall and<br> various flow demand with unreasonable flow management will be<br> caused destroyed of river ecosystem. Then, it is very serious to<br> determine ecosystem flow requirement. In this paper, Flow duration<br> curve indices method which has hydrological based was used to<br> evaluate environmental flow in Gharasou River, Ardabil, Iran. Using<br> flow duration curve, Q90 and Q95 for different return periods were<br> calculated. Their magnitude were determined as 1-day, 3-day, 7-day<br> and 30 day. According the second method, hydraulic alteration<br> indices often had low and medium range. In order to maintain river at<br> an acceptable ecological condition, minimum daily discharge of<br> index Q95 is 0.7 m3.s-1.
Siphon spillways are used when a discharge capacity is required in dam design without the use of ... more Siphon spillways are used when a discharge capacity is required in dam design without the use of operating gated spillways. Cavitation is an expected phenomenon in each hydraulic structure when the pressure goes below the critical value. In the present study, by using a physical model occurrence of cavitation along the siphon spillway was experimentally investigated. To do so by considering all scale effects, the effect of three bucket angles, four heads (difference between upstream and downstream elevation) and more than ten discharges were checked on cavitation index in more than fourteen points along the siphon spillway. To make results more practical and also make easy the engineering judgment, the siphon spillway was divided into three different zones and possibility of cavitation on each one was calculated. All experiments were conducted in free state at tail water and rectangular cross section. Results showed that without using the aerator, occurrence of cavitation is probabl...
2 Abstract: The estimation of snowmelt and rainfall runoff has very important where it is require... more 2 Abstract: The estimation of snowmelt and rainfall runoff has very important where it is required to plan water management programs. In this study, an attempt has been made to estimate daily discharge in Gharasoo basin, West-North of Iran during the 20th of February 1998 to fifth of June 1998 using Snowmelt Runoff Modeling(SRM) which is based on a degree-day method. Data from the 19 of February 1997 to twenty first of th v (0.7956,-9.21%) during calibration and validation periods, respectively. There was a good agreement between measured and calculated daily discharge.
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Papers by Mehdi Fuladipanah