The structural framework for a parametric catchment erosion model is proposed. A parameter optimization technique that provides a rational basis for the calibration of the model is developed. The adequacy of the model in representing a natural catchment is investigated.

Water injection strings in highly deviated wells are subjected to complex forces on the string bore. In this work, a mechanical model is developed for these forces and for those on downhole tools. On the basis of this model, and taking account of the characteristics of the string in different working conditions, a temperature field model and a pressure field model are introduced, and a statical...

background: female labor supply has been changed dramatically in the recent yr. in this study, we examined the effects of development on the relationship between fertility and female labor supply. methods: we used data of population and housing census of iran and estimated three separate models. to do this we employed logistic regressions (blr). results: the estimation results of our study show...

presence of distributed generation (dg) in electric distribution systems provides an attractive new alternative in capacity expansion planning of these systems. in this paper a new model is developed for solving simultaneous placement of hv/mv substations and dg units as a static planning tool. this model aims to minimize fixed and variable costs of planning. constraints related to dgs, substat...

  This paper aimed at estimation of the per capita consumption of electricity in residential sector based on economic indicators in Iran. The Genetic Algorithm Electricity Demand Model (GAEDM) was developed based on the past data using the genetic algorithm approach (GAA). The economic indicators used during the model development include: gross domestic product (GDP) in terms of per capita and ...

This paper is concerned with investigations into the effect of tension between the stands of the finishing mill on width control in a hot rolling process. An analysis is given to predict satisfactorily the variation in width due to spreading and also due to strip tension between the stands. Wusatowski's model which is developed to give an account of spreading is specified and a similar model to...

A mathematical model is developed and tested with plant data for the ammonia cold shot converter of Razi Petrochemical Complex. The model is based on a material and energy balance in a differential element of beds and is subjected to the assumptions of uniform distribution of temperature and composition through a general cross section and negligible mass and heat transfer in axial direction. Th...

This paper is concerned with investigations into the effect of tension between the stands of the finishing mill on width control in a hot rolling process. An analysis is given to predict satisfactorily the variation in width due to spreading and also due to strip tension between the stands. Wusatowskis model which is developed to give an account of spreading is specified and a similar model to ...

An accurate prediction of reaction kinetics of silicon nitridation is of great importance in designing procedure of material production and controlling of reaction. The main purpose of the present study is to investigate the effect of temperature on the kinetics of reaction bonded silicon nitride (RBSN) formation. To achieve this, nitrogen diffusion in the silicon nitride layer is considered as...

This study aimed to overcome the researchers' extreme attention to essentially qualitative methods in research on language learners' imagined communities and move towards quantification in order to achieve a more tangible image of this construct. To do so, the present researchers followed three main phases. First, a hypothesized model of language learners' imagined communities with eight compon...