• 자연과학논문집
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• 제10권1호
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• pp.13-16
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• 1998

원 위에서의 모든 복소 vector bundle은 line bundle로 나누어지며 첫째 Chern class는 복소 line bundle을 분류한다. 이것은 원위에서의 모든 복소 vector bundle은 trivial 하다는 것을 의미한다. 이 논문에서는 군작용이 있을 경우에는 원위에서의 복소 vector bundle중에 trivial하지 않는 bundle이 존재함을 보였다.

• 대한수학회지
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• 제47권6호
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• pp.1147-1165
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• 2010

In this paper we compare a torsion free sheaf F on $P^N$ and the free vector bundle $\oplus^n_{i=1}O_{P^N}(b_i)$ having same rank and splitting type. We show that the first one has always "less" global sections, while it has a higher second Chern class. In both cases bounds for the difference are found in terms of the maximal free subsheaves of F. As a consequence we obtain a direct, easy and more general proof of the "Horrocks' splitting criterion", also holding for torsion free sheaves, and lower bounds for the Chern classes $c_i$(F(t)) of twists of F, only depending on some numerical invariants of F. Especially, we prove for rank n torsion free sheaves on $P^N$, whose splitting type has no gap (i.e., $b_i{\geq}b_{i+1}{\geq}b_i-1$ 1 for every i = 1,$\ldots$,n-1), the following formula for the discriminant: $$\Delta(F):=2_{nc_2}-(n-1)c^2_1\geq-\frac{1}{12}n^2(n^2-1)$$. Finally in the case of rank n reflexive sheaves we obtain polynomial upper bounds for the absolute value of the higher Chern classes $c_3$(F(t)),$\ldots$,$c_n$(F(t)) for the dimension of the cohomology modules $H^iF(t)$ and for the Castelnuovo-Mumford regularity of F; these polynomial bounds only depend only on $c_1(F)$, $c_2(F)$, the splitting type of F and t.

• Korean Journal of Mathematics
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• 제7권1호
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• pp.79-84
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• 1999

• East Asian mathematical journal
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• 제14권2호
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• pp.371-375
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• 1998

• 대한수학회보
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• 제48권6호
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• pp.1329-1339
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• 2011

For a manifold with a linear connection, we find an obstruction class to have a volume form parallel with respect to its connection which corresponds to the Chern-Simons secondary invariant in the frame bundle of the manifold.

• 대한수학회지
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• 제40권3호
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• pp.461-486
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• 2003

It is known that the CR geometries of Levi non-degen-erate hypersurfaces in $\C^n$ and of the elliptic or hyperbolic CR submanifolds of codimension two in $\C^4$ share many common features. In this paper, a special class of normalized coordinates is introduced for any CR manifold M which is one of the above three kinds and it is shown that the explicit expression in these coordinates of an isotropy automorphism $f{\in}Aut(M)_o {\subset}Aut(M),\;o{\in}M$, is equal to the expression of a corresponding element of the automorphism group of the homogeneous model. As an application of this property, an extension theorem for CR maps is obtained.

• 대한수학회지
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• 제46권5호
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• pp.949-966
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• 2009

In this paper we introduce in study a new class of complex Finsler spaces, namely the complex Randers spaces, for which the fundamental metric tensor and the Chern-Finsler connection are determined. A special approach is devoted to $K{\ddot{a}}ahler$-Randers metrics. Using the length arc parametrization for the extremal curves of the Euler-Lagrange equations we obtain a complex nonlinear connections of Lorentz type in a complex Randers space.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.591-593
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• 2003

The study demonstrates the data extraction capabilities from the simulated ROCSAT-2 image by manual delineation. The GIS data are able to identify as fifteen categories of the classes I & II for the simulated ROCSAT-2 and SPOT image data. The areas of the paddy are identified almost the same results for both cases, but the arid farmland are identified differently about 30%. The ROCSAT-2 case can be also identified as seven more categories of the class III, but SPOT-4 case cannot.

• 디지털융복합연구
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• 제14권5호
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• pp.57-66
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• 2016

본 연구에서는 동양미래대학 컴퓨터정보공학과의 캡스톤디자인 관련 교과목을 소개하고, 2015년 1년 동안의 운영 사례를 통하여 컴퓨터공학 분야의 캡스톤디자인 모델을 제안한다. 2015학년도 1학기와 2학기에 각각 운영된 '시스템분석설계'와 '졸업작품(종합설계)'에 대한 운영 사례에서 수업 일정과 내용 등을 제시하고, 컴퓨터공학 분야에서 창의적 문제해결 능력을 갖춘 현장실무형 인재양성을 위한 캡스톤디자인의 성공적인 운영을 위해 캡스톤디자인 모델의 수행 단계를 교과목계획, 프로젝트계획, 개발 구현, 결과보고, 학생 및 교과목평가, 교과목환류의 6단계로 제안하며, 각 단계에서의 주요 사항을 제시한다. 본 연구의 캡스톤디자인 모델의 특징은 거시적인 관점에서 '교과목계획'과 '교과목환류'와 같은 사전 사후 단계의 필요성과 중요성을 제시하며, 소프트웨어공학 요소인 프로토타입과 형상관리 등을 활용한다는 점이다.