Fundamenta Informaticae - Volume 90, issue 1-2

Authors: Wang, Xia | Zhang, Wenxiu

Article Type: Research Article

Abstract: As an effective tool for data analysis and knowledge processing, the theory of concept lattices has been studied extensively and applied to various fields. In order to discover useful knowledge, one often ignores some attributes according to a particular purpose and merely considers the subcontexts of a rather complex context. In this paper, we make a deep investigation on the theory of concept lattices of subcontexts. An approach to construct the concept lattice of a context …is first presented by means of the concept lattices of its subcontexts. Then the concept lattices induced by all subcontexts of the context are considered as a set, and an order relation is introduced into the set. It is proved that the set together with the order relation is a complete lattice. Finally, the top element and the bottom element of the complete lattice are also obtained. Show more

Keywords: concept lattice, subcontext, congruence, closure operator, order relation

DOI: 10.3233/FI-2009-0011

Citation: Fundamenta Informaticae, vol. 90, no. 1-2, pp. 157-169, 2009

Authors: Yao, Chih-Chia | Yu, Pao-Ta | Hung, Ruo-Wei

Article Type: Research Article

Abstract: The major problem of SVMs is the dependence of the nonlinear separating surface on the entire dataset which creates unwieldy storage problems. This paper proposes a novel design algorithm, called the extractive support vector algorithm, which provides improved learning speed and a vastly improved performance. Instead of learning and training with all input patterns, the proposed algorithm selects support vectors from the input patterns and uses these support vectors as the training patterns. Experimental results reveal …that our proposed algorithmprovides near optimal solutions and outperforms the existing design algorithms. In addition, a significant framework which is based on extractive support vector algorithm is proposed for image restoration. In the framework, input patterns are classified by three filters: weighted order statistics filter, alpha-trimmed mean filter and identity filter. Our proposed filter can achieve three objectives: noise attenuation, chromaticity retention, and preservation of edges and details. Extensive simulation results illustrate that our proposed filter not only achieves these three objectives but also possesses robust and adaptive capabilities, and outperforms other proposed filtering techniques. Show more

Keywords: support vector machines, unwieldy storage, image restoration, weighted order statistics filter, alpha-trimmed mean filter

DOI: 10.3233/FI-2009-0012

Citation: Fundamenta Informaticae, vol. 90, no. 1-2, pp. 171-190, 2009

Authors: Zhang, Leyou | Hu, Yupu | Wu, Qing

Article Type: Research Article

Abstract: In this paper, a new construction of hierarchical ID-Based signature (HIBS) scheme is proposed. The new scheme has some advantages over the available schemes: the private keys size shrinks as the identity depth increases and the signature size is a constant as it consists of three group elements. Furthermore, under the h-CDH assumption, our scheme is provably secure in the standard model. This assumption is more natural than many of the hardness assumptions recently introduced to …HIBS in the standard model. Show more

Keywords: HIBS, standard model, h-CDH problem, provably secure

DOI: 10.3233/FI-2009-0013

Citation: Fundamenta Informaticae, vol. 90, no. 1-2, pp. 191-201, 2009