CSDL Bài trích Báo - Tạp chí
chủ đề: Algorithms techniques
1 An effective algorithm for computing reducts in decision tables / Do Si Truong, Lam Thanh Hien, Nguyen Thanh Tung // Tin học & Điều khiển học .- 2022 .- Vol 38(3) .- P. 277-292 .- 005
In this paper, we propose a reduct computing algorithm using attribute clustering. The proposed algorithm works in three main stages. In the first stage, irrelevant attributes are eliminated. In the second stage relevant attributes are divided into appropriately selected number of clusters by Partitioning Around Medoids (PAM) clustering method integrated with a special metric in attribute space which is the normalized variation of information. In the third stage, the representative attribute from each cluster is selected that is the most class-related. The selected attributes form the approximate reduct. The proposed algorithm is implemented and experimented. The experimental results show that the proposed algorithm is capable of computing approximate reduct with small size and high classification accuracy, when the number of clusters used to group the attributes is appropriately selected.
2 h-adaptive refinement strategies for triangular finite element meshes / Nguyen Trung Hieu // Khoa học & Công nghệ Đại học Duy Tân .- 2022 .- Số 5(54) .- P. 50-57 .- 515
In this paper, we present two different approaches to h-adaptively refine triangular finite element messes. These two strategies are designed to keep the shape regularity of the meshes almost the same and to preserve the sparsity pattern of the resulting system of equations.
3 p-adaptive meshing for triangular nodal finite elements meshes / Nguyen Trung Hieu // Khoa học & Công nghệ Đại học Duy Tân .- 2022 .- Số 5(54) .- P. 105-109 .- 515
In this paper, we present p-adaptive meshing algorithms (p-refinement and unrefinement) for triangular finite element meshes. The algorithms are designed to keep the computation cost low, and the neighboring elements are not too different in degree. In addition, we can prove that if we start with an admissible mesh, then each element can be refined at most once using the proposed algorithms. This is important because after a p-refinement there is no way to estimate its error without resolving the whole problem.