Fuzzy EOQ Model with Trapezoidal and Triangular Functions Using Partial Backorder

EOQ fuzzy model is EOQ model that can estimate the cost from existing information. Using trapezoid fuzzy functions can estimate the costs of existing and trapezoid membership functions has some points that have a value of membership . TR ̃C value results of trapezoid fuzzy will be higher than usual TRC value results of EOQ model . This paper aims to determine the optimal amount of inventory in the company, namely optimal Q and optimal V, using the model of partial backorder will be known optimal Q and V for the optimal number of units each time a message . EOQ model effect on inventory very closely by using EOQ fuzzy model with triangular and trapezoid membership functions with partial backorder. Optimal Q and optimal V values for the optimal fuzzy models will have an increase due to the use of trapezoid and triangular membership functions that have a different value depending on the requirements of each membership function value. Therefore, by using a fuzzy model can solve the company's problems in estimating the costs for the next term

Stable and Unstable Graphs With Total Irredundance Number Zero

For a graph G = (V, E), a set S ⊆ V is total irredundant if for every vertex v ∈ V, the set N[v] - N[S - {v}] is not empty. The total irredundance number irt(G) is the minimum cardinality of a maximal total irredundant set of G. We study the structure of the class of graphs which do not have any total irredundant sets; these are called irt(0)-graphs. Particular attention is given to the subclass of irt(0)-graphs whose total irredundance number either does not change (stable) or always changes (unstable) under arbitrary single edge additions. Also studied are irt(0)-graphs which are either stable or unstable under arbitrary single edge deletions