The group method of data handling technique (GMDH) and Box-Jenkins methods are two wellknown time series forecasting of mathematical modeling. In this paper, we introduce a hybrid modeling which combines the GMDH method with the Box-Jenkins method to model time series data. The Box-Jenkins method was used to determine the useful input variables of GMDH method and then the GMDH method which work...

in the present study, computational fluid dynamics (cfd) techniques and artificial neural networks (ann) are used to predict the pressure drop value (δp ) of al2o3-water nanofluid in flat tubes. δp  is predicted taking into account five input variables: tube flattening (h), inlet volumetric flow rate (qi  ), wall heat flux (qnw  ), nanoparticle volume fraction (φ) and nanoparticle diameter (dp ...

Most isolators have numerous displacements due to their low stiffness and damping properties. Accordingly, the supplementary systems vital roles in enhancement lower isolation system displacement. Nevertheless, many cases, even by utilising additional dampers systems, occurrence of residual displacement is inevitable. To address this issue, study, a new smart type bar hysteretic equipped with s...

in today’s world renewable energy is highly demanding because of increasing oil and fuelprices, desire and necessity to avert irreversible climate damage and also the unreliability of the non -renewablesources. in renewable energy, water is an important source. previously water is used only for survivalof human being as much as food but no attentionhas been givenen to economical use and conserv...

In this study, silk fibroin was extracted from cocoons of silkworms and fabricated into nonwoven mats by electrospinning method. A new model based on the group method of data handling (GMDH) and artificial neural network (ANN) was developed for estimation of the average diameter of electrospun silk fibroin nanofibers. In this regard, concentration, flow rate, voltage, distance, and speed of col...

The effective thermal conductivity (ETC) of soil is an essential parameter for the design and unhindered operation underground energy transportation storage systems. Various experimental, empirical, semi-empirical, mathematical, numerical methods have been tried in past, but lack either accuracy or are computationally cumbersome. recent developments computer science provided a new computational...

Accurate estimation of carbon and water fluxes of forest ecosystems is of particular importance for addressing the problems originating from global environmental change, and providing helpful information about carbon and water content for analyzing and diagnosing past and future climate change. The main focus of the current work was to investigate the feasibility of four comparatively new metho...

Many organelle enzymes coded for by nuclear genes have N-terminal sequences, which directs them into the organelle (precursor) and are removed upon import (mature). The experiments described below characterize the differences between the precursor and mature forms of watermelon glyoxysomal malate dehydrogenase. Using recombinant protein methods, the precursor (p-gMDH) and mature (gMDH) forms we...

In this paper we show how the performance of the basic algorithm of the Group Method of Data Handling (GMDH) can be improved using Genetic Algorithms (GA) and Particle Swarm Optimization (PSO). The new improved GMDH is then used to predict currency exchange rates: the US Dollar to the Euros. The performance of the hybrid GMDHs are compared with that of the conventional GMDH. Two performance mea...