data envelopment analysis (dea) has been proven as an efficient technique to evaluate the performance of homogeneous decision making units (dmus) where multiple inputs and outputs exist. in the conventional applications of dea, the data are considered as specific numerical values with explicit designation of being an input or output. however, the observed values of the data are sometimes imprec...

a‎s we know, developing mathematical models and numerical procedures that would appropriately treat and solve systems of linear equations where some of the system's parameters are proposed as fuzzy numbers is very important in fuzzy set theory. for this reason, many researchers have used various numerical methods to solve fuzzy linear systems. in this paper, we define the concepts of midpoint a...

Fuzzy numbers in number theory are a foundation of fuzzy sets and fuzzy mathematics that extend the domain of numbers from those of real numbers to fuzzy numbers. Fuzzy arithmetic is a system of fuzzy operations on fuzzy numbers. A theory of fuzzy arithmetic is presented towards a fuzzy mathematical structure for fuzzy inference and cognitive computation. The mathematical models of fuzzy number...

the aim of this paper is to introduce and study a new concept ofstrong double $(a)_ {delta}$-convergent sequence offuzzy numbers with respect to an orlicz function and also someproperties of the resulting sequence spaces of fuzzy   numbers areexamined. in addition, we define the double$(a,delta)$-statistical convergence of fuzzy  numbers andestablish some connections between the spaces of stron...

in this paper, we propose a new approach for ranking all fuzzynumbers based on revising the ranking method proposed by ezzati et al. cite{ezzati}.to this end, we present and investigate some properties of the proposed approach indetails. finally, to illustrate the advantage of the proposed method, it is applied to several groups of fuzzy numbers and the results are compared with other related a...

in order to have better insight of project characteristics, different kinds of fuzzy analysis for project networks have been recently proposed, most of which consider activities duration as the main and only source of imprecision and vagueness, but as it is usually experienced in real projects, the structure of the network is also subject to changes. in this paper we consider three types of imp...

‎ranking fuzzy numbers is generalization of the concepts of order, and class, and so have fundamental applications. moreover, deriving the final efficiency and powerful ranking are helpful to decision makers when solving fuzzy problems. selecting a good ranking method can apply to choosing a desired criterion in a fuzzy environment. there are numerous methods proposed for the ranking of fuzzy n...