Environmental problems are one of the most challenging issues for the entire world and each country. In economic studies, environmental issues are analyzed as negative externalities. In this article, the negative externalities of electricity production on the output growth of different sectors and household’s welfare in Iran’s economy have been studied through price system using Computable Gene...

the notion of sustainable development has rapidly gained considerable attention since the lastdecades of the twentieth century. it has become a locus for global paradigm shift on environment and development issues particularly after rio conference in 1992. the comparative analysis of agenda 21 and major un documents, mdg, and rio+20 as well as some major sources are made to provide a context fo...

in this paper, an optimization method for both weight and displacement of composite blades is presented. in   order to hold issues such as aerodynamics and acoustic unchanged, airfoil shape during optimization process remained constant. to achieve the ultimate goal, only blade lamination was changed. in order to achieve minimum weight for each part of the structure, the lowest layers are foreca...

Conducting qualitative research in applied linguistics seems to have some challenges. Hence, this study aimed to investigate the challenges of applied linguists across different research abilities to conduct qualitative studies. To that end, the biographical narratives, authored by 13 applied linguists, were collected. Then, the narratives were analyzed through qualitative data analysis princip...