Application of classical and novel integrated machine learning models to predict sediment discharge during free-flow flushing.

In this study, the capabilities of classical and novel integrated machine learning models were investigated to predict sediment discharge (Qs) in free-flow flushing. Developed models include Multivariate Linear Regression (MLR), Artificial Neural Network (ANN), Adaptive Neuro-Fuzzy Inference System (ANFIS), Group Method of Data Handling (GMDH), and four hybrid forms of GMDH and Support Vector Regression (SVR) in combination with Henry Gas Solubility Optimization (HGSO) and Equilibrium Optimizer (EO) algorithms. The number of 160 datasets that were applied to assess these models was extracted from the Janssen (PhD's Thesis, Engineering, Civil and Environmental Engineering. University of California, 1999) experimental study. Input parameters to predict Qs included the water level in the reservoir (hw), bed level in the flushing channel (hb), outflow (Qout), inflow (Qin), and elapsed time of flushing (T). The performance of all models was evaluated by four statistical indices of root mean square error (RMSE), mean absolute error (MAE), correlation coefficient (R2), and Mean absolute relative error (MARE). Evaluation of results demonstrated that the HGSO and EO algorithms could enhance the accuracy of the GMDH model (up to 26% and 22% in terms of RMSE), respectively. According to statistical criteria, the SVR-EO and SVR-HGSO provided the highest accuracy in both training (R2 = 0.98) and validation phases (R2 = 0.96). Moreover, among the developed models, the GMDH-HGSO algorithm provided excellent fitness to the observed data (R2 = 0.96, RMSE = 22.37, MAE = 15.65, and MARE = 0.26). The results indicated the high efficiency of the HGSO and EO algorithms in improving the accuracy of the GMDH and SVR models. However, among the developed models, the GMDH-HGSO is the most accurate model and is recommended for sediment transport modelling.

Calibration and validation of the Angstrom-Prescott model in solar radiation estimation using optimization algorithms.

The Angstrom-Prescott (A-P) model is widely suggested for estimating solar radiation (Rs) in areas without measured or deficiency of data. The aim of this research was calibration and validation of the coefficients of the A-P model at six meteorological stations across arid and semi-arid regions of Iran. This model has improved by adding the air temperature and relative humidity terms. Besides, the coefficients of the A-P model and improved models have calibrated using some optimization algorithms including Harmony Search (HS) and Shuffled Complex Evolution (SCE). Performance indices, i.e., Root Mean Square Error (RMSE), Mean Bias Error, and coefficient of determination (R2) have used to analyze the models ability in estimating Rs. The results indicated that the performance of the A-P model had more precision and less error than improved models in all the stations. In addition, the best results have obtained for the A-P model with the SCE algorithm. The RMSE varies between 0.82 and 2.67 MJ m-2 day-1 for the A-P model with the SCE algorithm in the calibration phase. In the SCE algorithm, the values of RMSE had decreased about 4% and 7% for Mashhad and Kerman stations in the calibration phase compared to the HS algorithm, respectively.

Multi-criteria analysis of site selection for groundwater recharge with treated municipal wastewater.

Geographic information systems (GIS) and remote sensing techniques are used as a decision support system to identify potential soil aquifer treatment (SAT) sites for groundwater recharge of Kerman aquifer, which is located in the southeast of Iran. These sites are identified using a single-objective multi-criteria analysis. To ensure technical feasibility, environmental sustainability, social acceptability and economical viability a number of criteria are considered for the site selection. The criteria selected for the different variables and acceptable ranges are based on standards published in national and international guidelines and technical documents. Multi-criteria evaluation was performed combining all produced thematic maps by means of the weighted index overlay method in order to select sites meeting all the criteria. The resulting map of this analysis shows potential sites are located in the north, southwest and southeast of the study area. Considering field observations, a potential site, which is located in the southwest of the study area, is proposed as the most suitable site for SAT. The result indicates that the study area has sufficient required suitable space for groundwater recharge with treated wastewater.

Effects of anthropometric factors on foot size in normal preschool children of Iran / Efectos de los factores antropométricos sobre el tamaño del pie en niños preescolares normales de Irán

The growth pattern of children is affected by anthropometric dimensions. This study was aimed to investigate anthropometric factors related to growth of preschool children of a sample population in Iran. This study was performed in year 2011 on 1320 of 4­7 years old preschool children in Arak. To classify, body mass index (BMI), height and weight were recorded. The four contact points (head, back, buttocks, and heels) were maintained against the spine of the stadiometer during measurement. The head was positioned in the Frankfurt plane, and the sliding bar was lowered the crown of the head. Height was measured and recorded by the researchers. A pair of manual calibrated Seca scales was used to measure body mass in kilograms. The participants were least dressed in the uniform. We have classified BMI to four groups as group1, BMI with 10.75­15 and group 2, 3, 4 with 15.1­17 and 17.1­20, 20.1­22.5, respectively. Foot length was recorded as the distance from the posterior aspect of the heel to the most distal aspect of the longest toe. Foot length was measured with subjects standing upright using a foot board, a plastic device with calibrated lineation (in centimeters and millimeters). Analysis showed that sex neither affect on BMI nor foot measurements. The present findings contribute to the understanding of the effect of body mass on the structural development of the pediatric foot and musculoskeletal system. Excessive body mass seems to lead to increased foot length and width.

El patrón de crecimiento de los niños se ve afectado por las dimensiones antropométricas. El objetivo fue investigar los factores antropométricos relacionados con el crecimiento de los niños en edad preescolar de una muestra poblacional de Irán. Este estudio se realizó en el año 2011 en 1320 niños, de 4-7 años, de edad preescolar de Arak. Para clasificar el índice de masa corporal (IMC), se registraron la altura y el peso. Los cuatro puntos de contacto (cabeza, espalda, glúteos y talones) se mantuvieron contra la columna del estadiómetro durante la medición. La cabeza fue colocada en el plano de Frankfurt, y la barra de deslizamiento se redujo al nivel de la corona de la cabeza. Los investigadores midieron y registraron la altura. Se utilizaronn par de escalas manuales Seca calibradas para medir la masa corporal en kilogramos. Los participantes fueron vestidos con el uniforme escolar. Se clasificó el IMC en cuatro grupos: grupo 1 entre 10,75­15, grupo 2 entre 15,1­17, grupo 3 entre 17,1­20 y grupo 4 entre 20,1­22,5. La longitud del pie se definió como la distancia existente desde la cara posterior del talón hasta la porción más distal del dedo más largo. La longitud de pie se midió con los sujetos en posición de pie utilizando una tabla de pie, dispositivo de plástico con la alineación calibrada (en centímetros y milímetros). El análisis mostró que el sexo no influye en el índice de masa corporal ni las medidas del pie. Los presentes hallazgos contribuyen a la comprensión de los efectos de la masa corporal en el desarrollo estructural del pie y el sistema músculo-esquelético pediátrico. La masa corporal excesiva parece conducir a un aumento de la longitud y ancho del pie.

How particle shape affects the flow through granular materials.

Flow through the pores of granular materials has many instances in practice. Therefore, it is interesting to realize how some parameters, such as the shape of the particles affect the passing flow. Following the recent mathematical theory proposed by the authors, this paper deals with the issue of how tortuosity and permeability are influenced by the particle shape. Comparison of the results with the experimental data reveals the competency of the theory in predicting the impact of particle geometry.

Analytical derivation of tortuosity and permeability of monosized spheres: a volume averaging approach.

Macroscopic properties of granular materials are important in modeling a variety of flow and transport phenomena in many fields of science. Determination of these parameters has always been an issue among both researchers and engineers, mainly in view of tortuosity and permeability. This paper presents analytical functions for the tortuosity and permeability of monosized sphere arrays based on a volume averaging approach and eliminates some ambiguities by modification of the original representative elementary volume model. Veracity of the proposed formulations has been illustrated through comparisons with the latest available results on the subject. Good agreement is found.