Let a,b∈R , with a≠b . The harmonic, logarithmic, and arithmetic means of a b are respectively defined by H(a,b)=21a+1b=2aba+b,L(a,b)=b−a ln b− ln a A(a,b)=a+b2 .Theorem. For 0<a<b,2a+b< ...

Production of several yeast products occur in presence of mixtures of monosaccharides. To study effect of xylose and glucose mixtures with system aeration and nitrogen source as the other two operative variables on xylitol production by Pichia guilliermondii, the present work was defined. Artificial Neural Network (ANN) strategy was used to athematically show interplay between these three c...

In this paper a modification on Levenberg-Marquardt algorithm for MLP neural network learning is proposed. The proposed algorithm has good convergence. This method reduces the amount of oscillation in learning procedure. An example is given to show usefulness of this method. Finally a simulation verifies the results of proposed method. Keywords—Levenberg-Marquardt, modification, neural network,...

Historically, wetlands have not been given much attention in terms of their value due to the general public being unaware. Nevertheless, are still threatened by many anthropogenic activities, addition ongoing climate change. With these recent developments, water level prediction has become an important task order identify potential environmental damage and for sustainable management wetlands. T...

In water- and wastewater-treatment processes, knowledge of sludge settlement behavior is a key requirement for proper design continuous clarifier or thickener. One the most robust practical tests to acquire information about rate sedimentation through execution batch settling tests. lieu conducting series various initial concentrations, it promising advantageous develop simple predictive models...

Nowadays 90% of the required water of Iran is secured with groundwater resources and forecasting of pollutants content in these resources is vital. Therefore, this research aimed to develop and employ the feedforward artificial neural network (ANN) to forecast the arsenic (As), lead (Pb), and zinc (Zn) concentration in groundwater resources of Asadabad plain. In this research, the ANN models we...

In this research samples of PVOH were synthesized at various reaction conditions (temperature, time, and amount of catalyst). First at 25˚C and 45˚C and constant catalyst weight samples of PVOH were prepared with different degree of hydrolysis at various times. For investigation of the effects of temperature, at times 20 and 40 min and constant weight of catalyst PVOH was prepared at various te...

Heat transfer fluids have inherently low thermal conductivity that greatly limits the heat exchange efficiency. While the effectiveness of extending surfaces and redesigning heat exchange equipments to increase the heat transfer rate has reached a limit, many research activities have been carried out attempting to improve the thermal transport properties of the fluids by adding more thermally c...

The two-phase frictional pressure drop has a dominant effect in many industrial applications associated with the multiphase flow. This study investigated accuracy of several available methods for predicting different pipe diameters using 4124 experimental data points. It is observed that performance existing poor wide range operating conditions. Then, Artificial Neural Network models were propo...