increasing of word demand load caused a new distributed generation (dg) to enter to powersystem. one of the most renewable energy is the photovoltaic system. it is beneficial to use thissystem in both separately as well as connected to power system using power electronics interface.in this paper an optimal pid controller for photovoltaic system systems has been developed. theoptimization techni...

In this article, a special type of orthogonalization is obtained to construct a multiple input transfer function model. By using this technique, construction of a transfer function model is divided to sequential construction of transfer function models with less input time series. Furthermore, based on real and simulated time series we provide an instruction to adequately perform the stages of ...

Cost function and factor demand estimation and measurement are among the most useful tools in economic analysis. This paper defines cost function flexibility in a new way that extends results and concepts from consumer demand theory to models of joint production. This applies to production models where input demand equations can be represented in terms of input prices, quasi-fixed inputs, and c...

in this paper the trade restrictiveness of agricultural policies in iran was measured by the triindex for the nine major agricultural products including wheat, rice, barely, maize, soybean,meat (beef meat), soybean oil, sugar and banana over the period 1981 to 2007. the main resultsindicate that there is no trend in above index and high volatility especially in 2006 and 2007years due to conside...

Petroleum (crude oil) is one of the most important resources of energy and its demand and consumption is growing while it is a non-renewable energy resource. Hence forecasting of its demand is necessary to plan appropriate strategies for managing future requirements. In this paper, three types of time series methods including univariate Seasonal ARIMA, Winters forecasting and Transfer Function-...

this study aims to estimate economic capacity and, in turn the utilization rate of economic capacity in iran’s electricity generation industry during 1350-1388. aggregate time series data for thermal power plants are used. with parametric restrictions for linear homogeneity in input prices imposed, capital demand function is first derived and estimated. this allows the derivation of economic ca...

in this study, first we evaluate the total amount of support for domestic cotton (ams) for the years 1988 to 1999. then, using time series data for the study years, translog cost function was constrained. having calculated the price elasticity of demand for farm inputs, farmers’ reactions to price changes due to the price liberalization were identified. the results of study showed that in the w...