Compactness and closedness are some of the important properties for studying topological spaces. Several types of these concepts (semi-compactness, pre-compactness, β-compactness,. . ., S-closedness, H-closedness, etc) occur in the literature. In this paper, we applied concept of φ operation which defined by Csaszar [8] to unify and generalized several characterizations and properties of lots o...

In this paper, the notions of countable S∗-compactness is introduced in L-topological spaces based on the notion of S∗-compactness. An S∗-compact L-set is countably S∗-compact. If L = [0, 1], then countable strong compactness implies countable S∗-compactness and countable S∗-compactness implies countable F-compactness, but each inverse is not true. The intersection of a countably S∗-compact L-s...

A kind of new fuzzy compactness, called near SR-compactness, is de4ned for an arbitrary L-subset and for L a complete DeMorgan algebra. This kind of fuzzy compactness is between Lowen’s strong fuzzy compactness and the second author’s SR-compactness. Characterizations and examples of near SR-compact L-subsets are given, and its topological properties are systematically investigated. c © 2003 El...

In this paper, a new notion of sequential compactness is introduced in L-topological spaces, which is called sequentially S∗-compactness. If L = [0, 1], sequential ultra-compactness, sequential N-compactness and sequential strong compactness imply sequential S∗-compactness, and sequential S∗-compactness implies sequential F-compactness. The intersection of a sequentially S∗-compact L-set and a ...

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...