we present a model and propose an approach to compute an approximate solution of fully fuzzy linear system $(ffls)$ of equations in which all the components of the coefficient matrix are either nonnegative or nonpositive. first, in discussing an $ffls$ with a nonnegative coefficient matrix, we consider an equivalent $ffls$ by using an appropriate permutation to simplify fuzzy multiplications. t...

this study considers an eoq inventory model with advance payment policy in a fuzzy situation by employing two types of fuzzy numbers that are trapezoidal and triangular. two fuzzy models are developed here. in the first model the cost parameters are fuzzified, but the demand rate is treated as crisp constant. in the second model, the demand rate is fuzzified but the cost parameters are treated ...

This paper deals with the problem of testing statisticalhypotheses when the available data are fuzzy. In this approach, wefirst obtain a fuzzy test statistic based on fuzzy data, and then,based on a new signed distance between fuzzy numbers, we introducea new decision rule to accept/reject the hypothesis of interest.The proposed approach is investigated for two cases: the casewithout nuisance p...

This paper presents two new types of fuzzy shortest-path network problems. We consider the edge weight of the network as uncertain, which means that it is either imprecise or unknown. Thus, the first type of fuzzy shortest-path problem uses triangular fuzzy numbers for the imprecise problem. The second type uses level (1 − β, 1 − α) interval-valued fuzzy numbers, which are based on past statist...

In this paper, we examine the reliability of a parallel system. We use the level (λ, ρ) interval-valued fuzzy numbers to find the fuzzy reliability of parallel systems and obtain the estimated reliability of the systems in the fuzzy sense by employing the signed distance method.

For the total cost of the inventory without backorder model, if we fuzzify the order quantity, the total demand, the cost of storing and the cost of placing an order as fuzzy numbers then we can obtain the fuzzy total cost. In this paper, we apply the signed distance method to defuzzify the fuzzy total cost and then solve the optimal order quantity.

In this paper, we consider fuzzy inventory with backorder. First, we fuzzify the storing cost a, backorder cost b, cost of placing an order c, total demand r, order quantity q, and shortage quantity s as the triangular fuzzy numbers in the total cost. From these, we can obtain the fuzzy total cost. Using the signed distance method to defuzzify, we get the estimate of the total cost in the fuzzy...

In this paper, a fuzzy based inventory model for imperfect quality items has been developed with shortages. The parameters fixed cost; holding cost and shortage cost are considered as fuzzy numbers. We considered the triangular fuzzy number to represents fuzzy parameters. The optimum order quantity is obtained in fuzzy sense with the help of signed distance method. The proposed model is illustr...

This article extends the Wilcoxon signed rank test for testing whether the median of a population is a specified constant by treating the observations as imprecise values. The test procedure is developed by using the concepts of “Credibility Theory” for studying the behavior of fuzzy phenomena. Numerical illustration of the proposed test is provided by representing the observations as trapezoid...