• 지구물리와물리탐사
• /
• 제6권4호
• /
• pp.180-186
• /
• 2003

수평(HCP)및 수직동일면(VCP)배열을 사용하는 다중 주파수 소형루프 전자탐사 자료의 1차원 역산 프로그램을 개발하였다. 역산방법은 ACB 최소자승법을 사용하였으며, Jacobian 행렬을 해석적으로 계산하였다. 간단한 1차원 모델에 대한 이론자료를 계산하고, 동상 및 이상성분 자료를 사용하여 역산을 수행하였다. 역산 결과 동상 및 이상성분을 모두 사용할 경우 가장 정확하게 각 층의 전기전도도 및 심도를 추정하는 것으로 나타났다.

• 대한수학회지
• /
• 제54권2호
• /
• pp.613-626
• /
• 2017

For the overdetermined linear system, when both the data matrix and the observed data are contaminated by noise, Total Least Squares method is an appropriate approach. Since an ill-conditioned data matrix with noise causes a large perturbation in the solution, some kind of regularization technique is required to filter out such noise. In this paper, we consider a Dual regularized Total Least Squares problem. Unlike the Tikhonov regularization which constrains the size of the solution, a Dual regularized Total Least Squares problem considers two constraints; one constrains the size of the error in the data matrix, the other constrains the size of the error in the observed data. Our method derives two nonlinear equations to construct the iterative method. However, since the Jacobian matrix of two nonlinear equations is not guaranteed to be nonsingular, we adopt a trust-region based iteration method to obtain the solution.

• Journal of applied mathematics & informatics
• /
• 제7권3호
• /
• pp.941-958
• /
• 2000

Euler method is generalized to solve the system of nonlinear differential equations. The generalization is carried out by taking a special constant matrix S so that exp(tS) can be exactly computed. Such a matrix S is extracted from the Jacobian matrix of the given problem. Stability of the generalized Euler process is discussed. It is shown that the generalized Euler process is comparable to the fourth order Runge-Kutta method. We also exemplify that the important qualitative and geometric features of the underlying dynamical system can be recovered by the generalized Euler process.

• 한국자동차공학회논문집
• /
• 제5권1호
• /
• pp.154-161
• /
• 1997

This paper presents the method to eliminate the constraint reaction in the Lagrange multiplier form equation of motion by using a generalized coordinate driveder from the velocity constraint equation. This method introduces a matrix method by considering the m dimensional space spanned by the rows of the constraint jacobian matrix. The orthogonal vectors defining the constraint manifold are projected to null vectors by the tangential vectors defined on the constraint manifold. Therefore the orthogonal projection matrix is defined by the tangential vectors. For correcting the generalized position coordinate, the optimization problem is formulated. And this correction process is analyzed by the quasi Newton method. Finally this method is verified through 3 dimensional vehicle model.

• 한국지능시스템학회논문지
• /
• 제24권1호
• /
• pp.84-89
• /
• 2014

본 논문에서는 카메라를 탑재한 전방향 이동 로봇에서의 표적 추종을 위한 영상기반 시각 서보 제어를 다룬다. 기존 연구에서는 카메라 영상에서 추출한 표적의 영상 좌표로부터 표적 추종을 위한 바퀴의 회전 각속도를 구하기 위하여 카메라의 수학적 모델과 이동 로봇의 기구학 특성으로부터 구한 수학적 영상 자코비안을 널리 활용하였다. 본 논문에서는 표적의 영상 좌표 정보를 이용한 단순한 규칙기반 제어 방식과 영상에 포착된 표적의 크기 정보를 조합하여 바퀴의 회전 각속도를 생성하는 새로운 방식을 제안한다. 카메라 영상을 몇 개의 영역으로 분할하고, 표적이 포함된 영역에 따라 미리 정의한 규칙을 적용하는데, 복잡한 수학적 표현을 사용하지 않으면서도 비교적 적은 수의 규칙을 사용하므로 구현이 용이한 장점이 있다. 제안된 방식은 실제 시스템으로 구현하여 실험하고, 전체 실험 시스템에 대한 설명과 함께 실험 결과를 제시하여 제안하는 방식의 타당성을 입증한다.

• Journal of Mechanical Science and Technology
• /
• 제14권2호
• /
• pp.159-167
• /
• 2000

A computational method for the dynamic analysis of a constrained mechanical system is presented in this paper. The partial velocity matrix, which is the null space of the Jacobian of the constraint equations, is used as the key ingredient for the derivation of reduced equations of motion. The acceleration constraint equations are solved simultaneously with the equations of motion. Thus, the total number of equations to be integrated is equivalent to that of the pseudo generalized coordinates, which denote all the variables employed to describe the configuration of the system of concern. Two well-known conventional methods are briefly introduced and compared with the present method. Three numerical examples are solved to demonstrate the solution accuracy, the computational efficiency, and the numerical stability of the present method.

• 대한기계학회논문집
• /
• 제15권5호
• /
• pp.1640-1648
• /
• 1991

본 연구에서는 이러한 편사 함수 최소화의 방법을 적용함에 있어 보다 안정된 수렴성과 계산 시간을 단축시키기 위하여 근접 위치 방법(near position method)을 개 발하여 적용하였다. 근접 위치 방법이란 이론적 해석법으로 풀기가 불가능한 기구학 을 갖는 6관절 로봇을 반복적 해석법을 사용한다는 것을 전제로 하여, 초기 위치를 목 표 위치에 가능한 근접하게 잡아서 반복 계산을 수행하는 방법으로써 로봇의 기구학적 자세에 따른 수렴의 불안정성을 방지하고, 계산 시간을 단축하는데 그 목적이 있다.

• 대한전기학회논문지
• /
• 제39권2호
• /
• pp.111-118
• /
• 1990

This paper presents a new algorithm of contingency analysis and countermeasure to alleviate the line overloads for electric power systems. In this algorithm, the inverse matrix of the new Jacobian matrix when a contingency occurs, in fastly calculated using the house-holder's Inverse Matrix Modification Lamma (IMML) with the original factor table. The generation outputs are firstly adjusted to alleviate all line overloads occurred by the contingency without tripping loads. If the generation adjustment is not enough anymore to alleviate line overloads, then the control of bus injection power is recommended to quickly alleviate remaining overloads with minimum amount of load tripping and generation read-justing at the termination busbars of the overload lines. The proposed algorithm has been validated in tests on the 6 busbar test system.

• 한국정밀공학회지
• /
• 제18권12호
• /
• pp.66-72
• /
• 2001

In this paper, by using pseudo-inverse matrix of the spatial redundant flexible manipulators, a position control method and its effect in vibration suppression was presented. Vibration suppression control was developed using lumped mass spring model of the flexible manipulators. With 2 elastic links and 7 rotory joint manipulator ADAM, (1)position control for no redundancy, and (2)position control for one redundant DOF(degree of freedom) were tested. The objective of this experiment is to show the effect of position control, using pseudo-inverse matrix. toward the improvement of operation, and at the same time, to reduce the vibration of the link and the magnitude of the joint torque.

• 호남수학학술지
• /
• 제37권4호
• /
• pp.569-575
• /
• 2015

In this paper, we research some properties of quaternionic regular functions in Clifford analysis. We investigate the corresponding Cauchy-Riemann system and find regularities of some hypercomplex valued functions.