• Journal of applied mathematics & informatics
• /
• v.27 no.1_2
• /
• pp.1-12
• /
• 2009

Iterative algorithms are proposed for the least-squares symmetric solution of AXB = E with a submatrix constraint. We characterize the linear mappings from their independent element space to the constrained solution sets, study their properties and use these properties to propose two matrix iterative algorithms that can find the minimum and quasi-minimum norm solution based on the classical LSQR algorithm for solving the unconstrained LS problem. Numerical results are provided that show the efficiency of the proposed methods.

• Communications of the Korean Mathematical Society
• /
• v.12 no.1
• /
• pp.27-36
• /
• 1997

A matrix whose entries consist of the symbols +, -, 0 is called a sign-pattern matrix. We characterize the $n \times n$ irreducible sign-pattern matrices that are sign tripotent.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.27-30
• /
• 2000

In this paper, we determine the design criteria of haptic device considering the human haptic system and determine the design specifications. We developed a new 2DOF haptic device based on the specifications. It has the wide workspace, statically-balanced, constant inertia matrix, well-conditioned Jacobian matrix and so on. There also is not singularity point within workspace of the device. We show that it has better performance than other 2DOF haptic device in the many aspects.

• Journal of applied mathematics & informatics
• /
• v.27 no.5_6
• /
• pp.1429-1433
• /
• 2009

The likelihood distance for the joint distribution of two multivariate normal distributions with common covariance matrix is explicitly derived. It is useful for identifying outliers which do not follow the joint multivariate normal distribution with common covariance matrix. The likelihood distance derived here is a good ground for the use of a generalized Wilks statistic in influence analysis of two multivariate normal data.

• Bulletin of the Korean Mathematical Society
• /
• v.38 no.1
• /
• pp.17-27
• /
• 2001

We discuss a finite difference preconditioner for the$C^1$ Lagrance quadratic spline collocation method for a uniformly elliptic operator with homogeneous Dirichlet boundary conditions. Using the generalized field of values argument, we analyzed eigenvalues of the matrix preconditioned by the matrix corresponding to a finite difference operator with zero boundary condition.

• Journal of applied mathematics & informatics
• /
• v.27 no.3_4
• /
• pp.943-953
• /
• 2009

In this paper, we give the lower and upper bounds for inverse elements of strictly diagonally dominant seventh-diagonal matrices, and improve the bounds on [SIAM. J. matrix Anal.App1.20(1999)820-837].

• Information and Communications Magazine
• /
• v.7 no.3
• /
• pp.27-34
• /
• 1990

The $(L,\psi)$ feature description on the binary boundary air craft image is introduced of classifying 3-D object (aircraft) identification. Three types for associative matrix memories are employed and tested for their classification performance. The fast association involved in these memories can be implemented using a parallel optical matrix-vector operation. Two associative memories are based on pseudoinverse solutions and the third one is interoduced as a paralell version of a nearest-neighbor classifier. Detailed simulation results for each associative processor are provided.

• Bulletin of the Korean Mathematical Society
• /
• v.27 no.2
• /
• pp.103-112
• /
• 1990

• The Mathematical Education
• /
• v.27 no.1
• /
• pp.29-35
• /
• 1988

• Kyungpook Mathematical Journal
• /
• v.27 no.1
• /
• pp.55-60
• /
• 1987

A linear system $\dot{x}= A(t)x$, with A(t+w)=A(t) is considered. A step function approximation of a periodic matrix is constructed. The stability criteria is discussed.