• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.10a
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• pp.177-181
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• 1996

Systematic classification system for standardization in telecommunication is essential to the standardization R&D strategy. This paper suggests a new reference model for development of work area and classification scheme related to the telecommunications standardization : Cubic and matrix approach. Standardization Work Areas(SWAs) that are upper level of the reference model are classified by its main role and function reflecting the market trends and user needs. Standardization expertise is lower level scheme, which can be regarded as the different possible layers of standardization to be applied to each one of the SWAs grouped under upper level scheme. A new reference model consists of two planes that are SWAs plane and Standardization layer plane. Finally the reference model for classification of SWAs in telecommunication mapping onto matrix table that row and column are defined by SWAs and standardization layer respectively.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.479-484
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• 1992

The resolved motion rate control (RMRC) is converting to Joint space trajectory from given Cartesian space trajectory. The RMRC requires the inverse of Jacobian matrix. Since the Jacobian matrix of the redundant robot is generally not square, the pseudo-inverse must be introduced. However the pseudo-inverse is not easy to be implemented on a digital computer in real time as well as mathematically complex. In this paper, a simple fuzzy resolved motion rate control (FRMRC) that can replace the RMRC using pseudo-inverse of Jacobian is proposed. The proposed FRMRC with appropriate fuzzy rules, membership functions and reasoning method can solve the mapping problem between the spaces without complexity. The mapped Joint space trajectory is sufficiently accurate so that it can be directly used to control redundant manipulators. Simulation results verify the efficiency of the proposed idea.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.699-702
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• 2000

In order to use a parallel device fur machine tool feed mechanism, it is very important to analyze its stiffness over the workspace. Generally, the stiffness of a rod varies with its length. In this paper, the stiffness of the leg is modeled as a linear function. With the linear stiffness model, the methods that can determine stiffness bounds and max/min stiffness directions are presented utilizing eigenvalues and eigenvectors of the stiffness matrix. The stiffness variation along a tool-path and stiffness mapping over a workspace are presented with cubic-shaped parallel device which is originally designed for machine tool feed mechanism.

• Journal of Korea Foundry Society
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• v.19 no.1
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• pp.66-70
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• 1999

In order to increase the wettability between ceramic fiber and metal matrix, ceramic fibers are generally coated with metal. In this paper, we examined how the nickel layers coated on continuous graphite fiber to increase the wettability are affected with variation applied pressure. In order to examine the behavior of nickel layer with variation of applied pressure, microstructure and nickel mapping of composites were investigated with SEM, and tensile properties of the composite were tested with UTM. As the applied pressure increases, nickel layers were resolved into the aluminum matrix and ultimate tensile strength of the composite decreased.

• Journal of Integrative Natural Science
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• v.11 no.1
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• pp.51-56
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• 2018

For topological vector spaces X and Y, let $F_0(X,Y)=\{f{\in}Y^X:f(0)=0\}$. Then it is an extremely large family and the family of linear operators is a very small subfamily of $F_0(X,Y)$. In this paper, we establish the characterizations of $F_0(X,Y)$-matrix families (${l^{\infty}(X)$, ${l^{\infty}(Y)$), ($c_0(X)$, $l^{\infty}(Y)$) and ($c_0(X)$, $l^{\infty}(Y)$).

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.450-455
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• 1998

In this paper, finite element with embedded discontinuous line is introduced in order to avoid the difficulties of adding new nodal points along with crack growth in discrete crack model. With the discontinuous element using discontinuous shape function, stiffness matrix of finite element is derived and dual mapping technique for numerical integration is employed. Using the finite element program made with employed algorithms, algorithm is verified and fracture analysis of simple concrete beam is performed.

• Journal of the Korean Mathematical Society
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• v.54 no.2
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• pp.493-506
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• 2017

In this paper, we define the modulus of n-dimensional U-flatness as the determinant of an $(n+1){\times}(n+1)$ matrix. The properties of the modulus are investigated and the relationships between this modulus and other geometric parameters of Banach spaces are studied. Some results on fixed point theory for non-expansive mappings and normal structure in Banach spaces are obtained.

• Honam Mathematical Journal
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• v.36 no.4
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• pp.777-786
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• 2014

We construct an orthonormal basis for the Bergman space associated to a simply connected domain. We use the or-thonormal basis for the Hardy space consisting of the Szegő kernel and the Riemann mapping function and rewrite their area integrals in terms of arc length integrals using the complex Green's identity. And we make a note about the matrix of a Toeplitz operator with respect to the orthonormal basis constructed in the paper.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.5B
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• pp.623-631
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• 2001

본 논문에서는 등간격 선형어레이로 입사한 인코히어런트신호의 도래각을 추정하기 위하여 행렬특성매핑을 기본으로 한 알고리듬을 제안한다. 알로리듬의 기본 개념은 공분산 행렬 초정값과 Frobenius norm 면에서 가장 가까운 공분산 행렬 (혹은 스펙트럼 밀도행렬)을 찾는 것이다. 제안된 알고리듬의 우수한 성능을 보여주기 위하여 협대역 신호인 경우에는 MUSIC과 광대역 신호인 경우에는 CSM-MUSIC과 컴퓨터 시뮬레이션을 통하여 통계적 성능을 비교하였다.

• Wind and Structures
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• v.16 no.5
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• pp.517-540
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• 2013

This paper presents applications of proper orthogonal decomposition in both the time and frequency domains based on both cross spectral matrix and covariance matrix branches to analyze multi-variate unsteady pressure fields on prisms and to study spanwise and chordwise pressure distribution. Furthermore, modification of proper orthogonal decomposition is applied to a rectangular spanwise coherence matrix in order to investigate the spanwise correlation and coherence of the unsteady pressure fields. The unsteady pressure fields have been directly measured in wind tunnel tests on some typical prisms with slenderness ratios B/D=1, B/D=1 with a splitter plate in the wake, and B/D=5. Significance and contribution of the first covariance mode associated with the first principal coordinates as well as those of the first spectral eigenvalue and associated spectral mode are clarified by synthesis of the unsteady pressure fields and identification of intrinsic events inside the unsteady pressure fields. Spanwise coherence of the unsteady pressure fields has been mapped the first time ever for better understanding of their intrinsic characteristics.