Islamic Azad University, Rasht BranchIranian Journal of Optimization2588-572306220140701A NEW APPROACH OF FUZZY NUMBERS WITH DIFFERENT SHAPES AND DEVIATION730736526829ENA. GhanizadehDepartment of Statistics, Islamic Azad University of Kermanshah Branch,
Kermanshah, IranN. ParandinDepartment of Mathematics, Islamic Azad University of Kermanshah Branch, Kermanshah, IranJournal Article20140120In this paper, we propose a new method for fuzzy numbers. In this method, we assume that A<sub>i</sub>= (a<sub>i1</sub>, a<sub>i2</sub>, a<sub>i3</sub>, a<sub>i4</sub>) is to be a fuzzy number. So, the convex combination of a<sub>i1</sub> and a<sub>i2 </sub>and also the convex combination of a<sub>i3</sub> and a<sub>i4</sub> are obtained separately. Then, M<sub>ic</sub> and M<sub>is</sub> that are to be the convex combinations and the standard deviation respectively we acquire them from these components. Finally, we can obtain ranking index (M<sub>i)</sub> that is the convex combination of, M<sub>ic</sub> and M<sub>is</sub>. At the end of paper, in one example, the proposed method is compared with other methods.http://ijo.iaurasht.ac.ir/article_526829_4387ae04443c3fe52b0c60ad9beeaa47.pdfIslamic Azad University, Rasht BranchIranian Journal of Optimization2588-572306220140701Unweighted p-center problem on extended stars737744526830ENJafar FathaliDepartment of Mathematics, Shahrood University of Technology, University Blvd., Shahrood, IranNader Jafari RadDepartment of Mathematics, Shahrood University of Technology, University Blvd., Shahrood, IranSadegh Rahimi SherbafDepartment of Mathematics, Shahrood University of Technology, University Blvd., Shahrood, IranJournal Article20140120An extended star is a tree which has only one vertex with degree larger than two. The -center problem in a graph asks to find a subset of the vertices of of cardinality such that the maximum weighted distances from to all vertices is minimized. In this paper we consider the -center problem on the unweighted extended stars, and present some properties to find solution.http://ijo.iaurasht.ac.ir/article_526830_37ef51736b0d3ec69e1bab922522c3ec.pdfIslamic Azad University, Rasht BranchIranian Journal of Optimization2588-572306220140701Application of G'/G-expansion method to the (2+1)-dimensional dispersive long wave equation745752526831ENJafar BiazarDepartment of Mathematics, Faculty of Science, University of GuilanZainab AyatiDepartment of Mathematics, Faculty of Science, University of GuilanJournal Article20140120In this work G'/G-expansion method has been employed to solve (2+1)-dimensional dispersive long wave equation. It is shown that G'/G-expansion method, with the help of symbolic computation, provides a very effective and powerful mathematical tool, for solving this equation.http://ijo.iaurasht.ac.ir/article_526831_5a32c146da7b46934bb4a19fbcc72b71.pdf