• 대한수학회보
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• 제52권3호
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• pp.955-962
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• 2015

It has been established that the role played by complete graphs in graph theory is similar to the role Dowling group geometries and Projective geometries play in matroid theory. In this paper, we introduce a notion of H-tree, a class of representable matroids which play a similar role to trees in graph theory. Then we give some properties of H-trees such that when q = 0, then the results reduce to the known properties of trees in graph theory. Finally we give explicit expressions of the characteristic polynomials of H-trees, H-cycles, H-fans and H-wheels.

• 대한수학회지
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• 제50권1호
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• pp.161-171
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• 2013

Given an integer $n{\geq}1$ and a compact group G, we find some restrictions for the probability that two randomly picked elements $x^n$ and $y$ of G commute. In the case $n=1$ this notion was investigated by W. H. Gustafson in 1973 and its influence on the structure of the group has been studied in the researches of several authors in last years.

• Interaction and multiscale mechanics
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• 제4권2호
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• pp.107-122
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• 2011

Mechanical behavior in nano-sized structures differs from those in macro sized structures due to surface effect. As the ratio of surface to volume increases, surface effect is not negligible and causes size-dependent mechanical behavior. In order to identify this size effect, atomistic simulations are required; however, it has many limitations because too much computational resource and time are needed. To overcome the restrictions of the atomistic simulations and graft the well-established continuum theories, the continuum model considering surface effect, which is based on the bridging technique between atomistic and continuum simulations, is introduced. Because it reflects the size effect, it is possible to carry out a variety of analysis which is intractable in the atomistic simulations. As a part of the application examples, the homogenization method is applied to micro/nano thin films with porosity and the homogenized elastic coefficients of the nano scale thickness porous films are computed in this paper.

• 대한수학회논문집
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• 제35권2호
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• pp.625-637
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• 2020

The object of the present paper is to characterize 3-dimensional trans-Sasakian manifolds of type (α, β) admitting ∗-Ricci solitons and ∗-gradient Ricci solitons. Under certain restrictions on the smooth functions α and β, we have proved that a trans-Sasakian 3-manifold of type (α, β) admitting a ∗-Ricci soliton reduces to a β-Kenmotsu manifold and admitting a ∗-gradient Ricci soliton is either flat or ∗-Einstein or it becomes a β-Kenmotsu manifold. Also an illustrative example is presented to verify our results.

• 한국IT서비스학회지
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• 제8권2호
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• pp.157-171
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• 2009

In mobile XML environments, the efficient synchronization technique is required to maintain the consistency of replicated XML data because the same data can be replicated between so many different XML documents. In this paper, we propose a message digest based synchronization technique to maintain the consistency of replicated data between client XML documents and a server XML database in mobile XML environments. The proposed an XML data synchronization technique(XSA) has the advantage of model generality aspect and storage space aspect by using the tuple-based message digest table to detect the data conflicts. The proposed technique can be applicable to the application requiring the consistency of replicated XML data without any restrictions in the heterogeneous(between hierarchical XML documents and relational XML databases) mobile environments.

• 한국정보과학회논문지:소프트웨어및응용
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• 제26권9호
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• pp.1132-1140
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• 1999

한국어에서 보조사로 인해 발생하는 격 모호성(case ambiguity) 문제를 해결하는 알고리즘을 개발하였다. 이 알고리즘은 용언의 하위범주화 사전, 용언과 그 용언의 보어가 되는 체언간의 선택 제약, 체언의 의미 정보를 제공하는 시소러스 등의 구문.의미 지식과 더불어 몇 가지의 휴리스틱 규칙을 이용하며, 필수 보어의 생략이 흔한 한국어의 특성에 잘 대응한다. 중규모의 하위범주화 사전 및 시소러스를 이용한 실험에서 만족할 만한 성능을 보였다.Abstract An algorithm is proposed for the resolution of case ambiguity caused by the use of auxiliary postpositions in Korean language. The algorithm utilizes verb dictionary which provides subcategorization information and selectional restrictions, and the thesaurus as well as a set of simple heuristic rules. The algorithm is appropriate for Korean language where required complements are often omitted. The algorithm performed successfully in an experiment using medium-sized subcategorization dictionary and thesaurus.

• 지능정보연구
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• 제9권2호
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• pp.39-50
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• 2003

Deleting unsolicited email, popularly known as spam mail, is an annoying task for Internet users. Moreover, spam mail causes a variety of social problems. At present, legal restrictions cannot eradicate spam senders. As a result, many technical methods to eliminate spam mail such as spam filtering and online stamps have been introduced. However, the process of blocking spam mail can inadvertently result in suspension of indispensable or beneficial communication. In this paper, we propose a certificate and agent based emailing architecture that can block spam mail, while at the same time approve certified mail. This architecture can be accelerated by synergistic utilization of digital signature and electronic document interchange.

• 지식경영연구
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• 제10권1호
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• pp.17-32
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• 2009

Cyber University has been continuously increased since it is of great necessity of education through lifelong study. Recently, the management of cyber universities does not ensure education success, because some problems are coming out. Now we are to take an interest in qualitative level of e-learning. The purpose of this study is to classify and investigate interaction factors of e-learning, which were one of the restrictions to develop e-learning, influence learning flow and satisfaction. The authors discuss the implications of the findings for interaction and learning flow theory and practice.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2003년도 추계학술발표대회(하)
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• pp.601-604
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• 2003

신발 설계 시스템에서 그레이딩 기능은 기본 사이즈로 설계된 신발 라스트를 생산하고자 하는 여러 사이즈로 변환하는 작업이다. 그레이딩(Grading) 작업은 전체적으로 적용되는 제로 그레이딩(Zero Grading)과 특정한 부분에 개별적인 룰을 적용하는 센터 그레이딩(Center Grading)으로 구분된다. 이 두 방식을 혼용하여 그레이딩 작업을 수행하는데, 이 때, 휘어짐이나 일그러짐과 같은 부적절한 결과가 발생할 수 있고, 이런 오류를 보정하기 위해 제약조건들(Restrictions)을 적용한다. 이와 같이 센터 그레이딩과 제약조건들을 적용한 그레이딩을 특수 그레이딩이라 한다. 기존의 신발 설계 시스템에서는 이런 특수 그레이딩에 대해 속도가 느리거나, 기능이 미비하거나 지원하지 않는 문제점이 있다 본 논문에서는 이런 문제점들을 해결하고, 특수 그레이딩을 위한 제약조건을 다중으로 적용할 수 있도록 보완하였다.

• 대한수학회보
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• 제46권6호
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• pp.1079-1089
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• 2009

In this paper, we shall show that for any entire function f, the function of the form $f^m(f^n$ - 1)f' has no non-zero finite Picard value for all positive integers m, n ${\in}\;{\mathbb{N}}$ possibly except for the special case m = n = 1. Furthermore, we shall also show that for any two nonconstant meromorphic functions f and g, if $f^m(f^n$-1)f' and $g^m(g^n$-1)g' share the value 1 weakly, then f $\equiv$ g provided that m and n satisfy some conditions. In particular, if f and g are entire, then the restrictions on m and n could be greatly reduced.