A new secure knapsack cryptosystem based on the Merkle-Hellman public key cryptosystem will be proposed in this paper. Although it is common sense that when the density is low, the knapsack cryptosystem turns vulnerable to the low-density attack. The density d of a secure knapsack cryptosystem must be larger than 0 9408 . to avoid low-density attack. In this paper, we investigate a new Permutat...

We consider the minimization version of the multi-dimensional knapsack problem with bounded integer variables. We propose a greedy approximation algorithm that runs in O(mn) time and has a guarantee of m + 1, where n is the number of items and m is the number of knapsack constraints. The guarantee of the algorithm can be improved in case of easy coefficients in the constraints associated with s...

We study the Knapsack Problem with Conflict Graph (KPCG), an extension of the 0-1 Knapsack Problem, in which a conflict graph describing incompatibilities between items is given. The goal of the KPCG is to select the maximum profit set of compatible items while satisfying the knapsack capacity constraint. We present a new Branch-and-Bound approach to derive optimal solutions to the KPCG in shor...

This paper considers knapsack problem with fuzzy weights, says fuzzy knapsack problem (FKP). Here we introduce possibility index which gives the possibility of choosing the items with fuzzy weights for knapsack with crisp capacity. In this paper a dynamic programming technique has been introduced to optimize the utility value of objective function. An algorithm has been proposed which gives the...

In this note we study packing or covering integer programs with at most k constraints, which are also known as k-dimensional knapsack problems. For integer k > 0 and real ǫ > 0, we observe there is a polynomial-sized LP for the k-dimensional knapsack problem with integrality gap at most 1+ ǫ. The variables may be unbounded or have arbitrary upper bounds. In the (classical) packing case, we can ...

2 Knapsack Problem (continued) 2.1 Algorithm Recap Definition: We define states (sub-problems) as the following: the maximum value for a knapsack with capacity j and we are given the first i items. Then, we have ∀i, j, the corresponding state, a[i, j] is max(a[i−1, j−wi] + vi, a[i−1, j]), where the first option is the value if item i is in the knapsack and the second option is the value if item...

Mathematical models of biogeography inspired the development of the biogeography-based optimization algorithm. In this article we propose a binary version of biogeography-based optimization (BBO) for the Knapsack Problem. Two new mutation operators are proposed to extend the biogeography-based optimization algorithm to binary optimization problems. We also demonstrate the performance of the res...

In this thesis a method for solving the Generalized Assignment Problem (GAP) is described. It is based on a reformulation of the original problem into a Set Partitioning Problem (SPP), in which the columns represent partial solutions to the original problem. For solving this problem, column generation, with systematic overgeneration of columns, is used. Conditions that guarantee that an optimal...