This paper presents an approach for the comparative study on Data Encryption Standard (DES) using Differential Cryptanalysis and Linear cryptanalysis. In this paper, cipher text only attack is adopted and varieties of optimum keys are generated based on the cost function values. The goal of this paper is two fold. First we want to make a study about how evolutionary computation techniques can e...

The linear cryptanalysis proposed by Matsui is one of the most effective attacks on block ciphers, and he demonstrated an experimental cryptanalysis against DES at CRYPTO 1994. In this paper, we show how to optimize the linear cryptanalysis on modern microprocessors. Nowadays, there are two methods of implementing the linear cryptanalysis. Method 1 reduces the time complexity by reducing the nu...

We address in this paper a new computational biology problem that aims at understanding a mechanism that could potentially be used to genetically manipulate natural insect populations infected by inherited, intra-cellular parasitic bacteria. In this problem, that we denote by Mod/Resc Parsimony Inference, we are given a boolean matrix and the goal is to find two other boolean matrices with a mi...

An ordered biclique partition of the complete graph Kn on n vertices is a collection of bicliques (i.e., complete bipartite graphs) such that (i) every edge of Kn is covered by at least one and at most two bicliques in the collection, and (ii) if an edge e is covered by two bicliques then each endpoint of e is in the first class in one of these bicliques and in the second class in other one. We...

Many real world applications rely on the discovery of maximal biclique subgraphs (complete bipartite subgraphs). However, existing algorithms for enumerating maximal bicliques are not very efficient in practice. In this paper, we propose an efficient algorithm to mine large maximal biclique subgraphs from undirected graphs. Our algorithm uses a divide-and-conquer approach. It effectively uses t...

We investigate the following lower bound methods for regular languages: The fooling set technique, the extended fooling set technique, and the biclique edge cover technique. It is shown that the maximal attainable lower bound for each of the above mentioned techniques can be algorithmically deduced from a canonical finite graph, the so called dependency graph of a regular language. This graph i...

Inapproximability results concerning minimization of nondeterministic finite automata relative to given deterministic finite automata were obtained only recently, modulo cryptographic assumptions [4]. Here we give upper and lower bounds on the approximability of this problem utilizing only the common assumption P 6= NP, in the setup where the input is a finite language specified by a truth tabl...