Fundamenta Informaticae - Volume 83, issue 3

Authors: Ghosh, Ashish | Das, Mrinal Kanti

Article Type: Research Article

Abstract: In this paper a new concept of ranking among the solutions of the same front, along with elite preservation mechanism and ensuring diversity through the nearest neighbor method is proposed for multi-objective genetic algorithms. This algorithm is applied on a set of benchmark multi-objective test problems and the results are compared with that of NSGA-II (a similar algorithm). The proposed algorithm is seen to over perform the existing algorithm. More specifically, the new approach has been …used to solve the deceptive multi-objective optimization problems in a better way. Show more

Keywords: Multi-objective optimization, evolutionary computing, genetic algorithms, Pareto optimality

Citation: Fundamenta Informaticae, vol. 83, no. 3, pp. 231-252, 2008

Authors: Grimberg, Benjamin | Kaminski, Michael

Article Type: Research Article

Abstract: We study the extension of propositional ground non-monotonic modal logic to the firstorder case. We show that first-order ground non-monotonic modal logic well complies with first-order default logic by interpreting the latter in the former by the Truszczyński like translation and present a minimal model semantics of first-order ground non-monotonicmodal logic.

Keywords: First-order ground non-monotonic modal logic, first-order default logic, preference semantics, minimal model semantics, Herbrand semantics

Citation: Fundamenta Informaticae, vol. 83, no. 3, pp. 253-276, 2008

Authors: Laugerotte, Éric | Ziadi, Djelloul

Article Type: Research Article

Abstract: In this paper, we introduce the notion of Thompson weighted automaton. We show that an ε-free automaton constructed from the Thompson weighted automaton for a regular weighted expression E can be computed in quadratic time on the size of E. Moreover the coefficient of a word u in the noncommutative formal series associated to E, can be computed in time O(∣u∣ × �E∣).

Keywords: Star, weighted automata, regular weighted expressions, Thompson automata, elimination, recognizable words

Citation: Fundamenta Informaticae, vol. 83, no. 3, pp. 277-298, 2008

Authors: Lin, Chia-Chen | Wang, Shing-Shoung

Article Type: Research Article

Abstract: This paper presents a novel scheme to detect copied versions of digital images, particularly in an Internet environment based on edge information of images. The edge information is used to generate the signature set for a corresponding image. The edge-based signature sets are then used to compute the distortions between query images and test images, from among which a user wants to find copies. Experimental results confirm that the proposed scheme not only withstands various modifications …of an original image but also offers good detection performance in dealing with various rotations, shifting of 17.5% of the width or height of an image, and cutting out up to 45% of the area of an image, which previous research work has found difficult to detect. Therefore, our proposed scheme could be very helpful in detecting copies of digital images transmitted in an Internet environment. Show more

Keywords: Image copy detection, copyright protection, edge-detection, rotation, shifting

Citation: Fundamenta Informaticae, vol. 83, no. 3, pp. 299-318, 2008

Authors: Liu, Jen-Chang | Shih, Ming-Hong

Article Type: Research Article

Abstract: Generalizations of the pixel-value differencing (PVD) method for data hiding in graylevel images are proposed. Two extensions of the PVD method are analyzed: the block-based approach and the Haar-based approach. For the block-based PVD, the cover image is divided into non-overlapping horizontal or square blocks of n pixels. In each block, n − 1 differences are calculated between consecutive pixels. These differences are classified to embed the secret message. For the Haar-based PVD, the 2-D integer …Haar wavelet is applied to decomposed the cover image. The high-frequency components are used to hide message. Higher level of Haar decomposition allows more bits to be embedded. For both proposed generalizations, the capacity of the embeddedmessage is significantly increased. Moreover, both generalizations are invulnerable to the RS-diagram and histogram steganalysis. Show more

Keywords: Data hiding, Pixel-value differencing, Steganography, Haar wavelet

Citation: Fundamenta Informaticae, vol. 83, no. 3, pp. 319-335, 2008