abstract regarding the imprecise or fuzzy data on the agriculture activities, applying models based on fuzzy data may be useful. in line with this condition this study tries to compare the ability of possiblistic programming approach in developing optimal solution with fuzzy and deterministic programming. to get this objective a data set obtained from 90 farmers of kohgilooye region, gathered i...

In this article, the problem of determining the shape of a thin wing for minimum drag has been examined. In order to determine the optimal shape, we have extended a measure theory-based method. Using an embedding procedure, the problem of finding the optimal shape is reduced to one consisting of minimizing a linear form over a set of positive measures. The resulting problem can be approximated ...

The Unique Coverage problem, given a universe V of elements and a collection E of subsets of V , asks to find S ⊆V to maximize the number of e ∈ E that intersects S in exactly one element. When each e ∈ E has cardinality at most k, it is also known as 1-in-k Hitting Set, and admits a simple Ω( 1 logk )-approximation algorithm. For constant k, we prove that 1-in-k Hitting Set is NP-hard to appro...

In this paper, the construction of nearly optimal multiway trees for n keys, n key weights, and n + 1 gap weights, is investigated. we present an efficient algorithm for this problem having a time complexity of O(H tn), where H is the height of the resulting tree and t is its order. The algorithm is based on a top down approach. For a given set of keys, we determine a subset of keys that should...