• 대한수학회보
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• 제52권3호
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• pp.977-986
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• 2015

Let G be a graph on the vertex set $V(G)=\{x_1,{\cdots},x_n\}$ with the edge set E(G), and let $R=K[x_1,{\cdots},x_n]$ be the polynomial ring over a field K. Two monomial ideals are associated to G, the edge ideal I(G) generated by all monomials $x_i,x_j$ with $\{x_i,x_j\}{\in}E(G)$, and the vertex cover ideal $I_G$ generated by monomials ${\prod}_{x_i{\in}C}{^{x_i}}$ for all minimal vertex covers C of G. A minimal vertex cover of G is a subset $C{\subset}V(G)$ such that each edge has at least one vertex in C and no proper subset of C has the same property. Indeed, the vertex cover ideal of G is the Alexander dual of the edge ideal of G. In this paper, for an unmixed bipartite graph G we consider the lattice of vertex covers $L_G$ and we explicitly describe the minimal free resolution of the ideal associated to $L_G$ which is exactly the vertex cover ideal of G. Then we compute depth, projective dimension, regularity and extremal Betti numbers of R/I(G) in terms of the associated lattice.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2003년도 춘계종합학술대회논문집
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• pp.406-410
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• 2003

B.M. Schen([2])은 함수의 합성 "${\circ}$" 과 차집합 연산 "-"에 대하여 닫혀있는 함수들의 집합 ${\Phi}$에서의 대수적 구조인 subtraction semigroup (${\Phi}$; ${\circ}$,-)를 정의하였다. 이 구조에서 (${\Phi}$; ${\circ}$)는 semgroup, (${\Phi}$; -)는 [1]에서 정의한 subtraction algebra를 이룬다. B.M. Schen은 [2]에서 모든 subtraction semigroup은 invertible function들의 difference semigroup과 동형이라는 사실을 밝혔다. 본 논문에서는 이 subtraction semigroup의 일반화로써 near subtraction semigroupd을 정의하고 이의 한 특수한 형태인 strong near subtraction semigroup의 개념을 정의하여 이들의 일반적인 성질과 ideal의 특성을 조사하고 이들의 응용도를 조사하고자 한다.

• 대한수학회보
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• 제57권2호
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• pp.407-417
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• 2020

Let (R, m) be a d-dimensional Cohen-Macaulay local ring with infinite residue field. Let I be an ideal of R that has analytic spread ℓ(I) = d, satisfies the G_d condition, the weak Artin-Nagata property AN^-_d-2 and m is not an associated prime of R/I. In this paper, we show that if j₁(I) = λ(I/J) + λ[R/(J_d-1 :_RI+(J_d-2 :_RI+I):_R m^∞)] + 1, then I has almost minimal j-multiplicity, G(I) is Cohen-Macaulay and r_J(I) is at most 2, where J = (x₁, _…, x_d) is a general minimal reduction of I and J_i = (x₁, _…, x_i). In addition, the last theorem is in the spirit of a result of Sally who has studied the depth of associated graded rings and minimal reductions for m-primary ideals.

• 대한간호학회지
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• 제42권5호
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• pp.759-770
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• 2012

Purpose: This ethnography was done to explore patterns of weight management behavior among adults using obesity clinics. Methods: The participants were 12 adults who were overweight or obese and 2 family members. Data were collected from iterative fieldwork in the obesity clinics of two hospitals. Data were analyzed using text analysis and taxonomic methods. Results: Weight management behaviors among participants varied according to the recognition of the body and motivation for weight control, Participants' behavior was discussed in the socio-cultural context of obesity. Patterns of weight management behavior among participants were categorized by focus: strategic self-oriented type including managements for the body as a social asset and for health, selective neglect type, and passive group value-oriented type including type dependent on others and managements for beauty. Conclusion: Participants' weight management behavior was guided by folk concepts of body and health. and constructed within the socio-cultural context. It is necessary for health care providers to understand physical and psychological problems arising from the repeated trials, excessive control of weight, and Western cultural discourse on beauty ideals among adults who are overweight or obese. Therefore, interventions should be tailored to address individual and community needs.

• 건축역사연구
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• 제7권1호
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• pp.93-108
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• 1998

The threads of this thesis are several theoretical issues of modern urban ideals. Modern architects and urban designers conceived their individual artifacts, which assumed to be laid out on the new settings totally different from the existing urban fabrics derived from inherently medieval ones. In the discussion of modern ideal society, the Industrial Revolution and the Enlightenment was a pivotal point. Innovations in technology and expanded living territories since the double revolution have been critical factors in the evolution of new ideas of urbanism. The tremendous success in science and technology led a way to the 'science-fiction' environment as a destined apocalyptic world. The dream, whether it was socialist or in any other believes, to a pastoral utopia beyond the capitalist society was represented through the ideal cities, which were modern versions of arcadia in the other approaches. Two sides of revolutionary ideas are presented as a futurist city and a garden city, which are on the separate notions but co-existed or overlapped in a single urban project such as in Le Corbusier urban schemes or even Tchumi's recent work, Parc de la Villette. Urban ideas in the twentieth century are based on urban naturalism, the notion of which was consistant from abbe Laugier to Le Corbusier, as well as machine aesthetics interpreted in terms of archeological research and modern technology.

• 한국전자통신학회논문지
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• 제6권1호
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• pp.90-96
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• 2011

본 논문에서는 비-최대 복소 이차 정수환(order)의 가역 이데알의 특성을 이용하는 암호계중에서 매우 중요한 이산대수문제(DLP)를 제안하고 그의 안전성을 분석하려고 한다. 우선 이러한 이산대수문제를 제안하게 된 수학적인 배경을 소개한 다음, Cls (O) 위에서 안전한 이산대수문제를 구축 한다. 또한 제안된 암호계의 안전성을 결정하는 최대 복소 이차 정수환의 류군(class group)의 류수(class number)와 비최대 류반군(class semigroup)의 류수를 비교하여 안전성이 증가하는 정도를 계산한다. 마지막으로 이데알의 소 이데알 인수분해과정에서 유일인수분해의 가능성 문제를 기반으로 최대 order의 류군(class group)위에서의 DLP와 비최대 류반군(class semigroup)위에서의 DLP를 비교하면서, 본 논문에서 제안된 DLP의 안전성을 검증하고자 한다.

• East Asian mathematical journal
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• 제30권5호
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• pp.617-623
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• 2014

Due to Bell, a ring R is usually said to be IFP if ab = 0 implies aRb = 0 for $a,b{\in}R$. It is shown that if f(x)g(x) = 0 for $f(x)=a_0+a_1x$ and $g(x)=b_0+{\cdots}+b_nx^n$ in R[x], then $(f(x)R[x])^{2n+2}g(x)=0$. Motivated by this results, we study the structure of the IFP when proper ideals are taken in place of R, introducing the concept of insertion-of-ideal-factors-property (simply, IIFP) as a generalization of the IFP. A ring R will be called an IIFP ring if ab = 0 (for $a,b{\in}R$) implies aIb = 0 for some proper nonzero ideal I of R, where R is assumed to be non-simple. We in this note study the basic structure of IIFP rings.

• 한국교육논총
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• 제38권3호
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• pp.189-210
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• 2018

본고는 천원 오천석의 민주주의 교육에 대한 현대적 의미를 제고한다. 특히 그의 후기 저서에 강조된 민족주의에 대한 논의 또한 요구되는 바이나 본고에서는 천원의 민주주의 교육이념 나타난 자유 개념을 분석하는 것으로 한정짓도록 한다. 이를 위하여 오늘날의 시대적 담론을 비판적으로 분석한 한병철의 논의를 바탕으로 천원의 민주주의의 의미와 평가를 논하고 그의 사상에 내재된 교육철학적 한계를 비판적으로 고찰한다. 이를 바탕으로 천원이 궁극적으로 지향하였던 도의적 민주주의 사상을 제고하여 오늘날 픽미세대에게 요구되는 자유 개념을 고찰하도록 한다.

• Korean Journal of Mathematics
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• 제20권4호
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• pp.423-431
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• 2012

There have been some study characterizing monoids by homological classification using the properties around projectivity, injectivity, or regularity of acts. In particular Kilp and Knauer([4]) have analyzed monoids over which all acts with one of the properties around projectivity or injectivity are regular. However Kilp and Knauer left over problems of characterization of monoids over which all regular right S-acts are (weakly) at, (weakly) injective or faithful. Among these open problems, Liu([3]) proved that all regular right S-acts are (weakly) at if and only if es is a von Neumann regular element of S for all $s{\in}S$ and $e^2=e{\in}T$, and that all regular right S-acts are faithful if and only if all right ideals eS, $e^2=e{\in}T$, are faithful. But it still remains an open question to characterize over which all regular right S-acts are weakly injective or injective. Hence the purpose of this study is to investigate the relations between regular right S-acts and weakly injective right S-acts, and then characterize the monoid over which all regular right S-acts are weakly injective.

• 대한한의학원전학회지
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• 제26권1호
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• pp.65-69
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• 2013

Objective : The main topic of this study is how the contribution of Treatiseon Febrile Diseases and midcellaneous diseases written by Zhang Zhongjing(张仲景) to the theory of spleen and stomach has been. Method : Analysis of formula in Treatiseon Febrile Diseases and midcellaneous diseases with theoretical and historical perspectives is the main method of the study. Result : The theory of spleen and stomach，which is formed in the long term medical practice, is the important component theory of traditional Chinese medicine. Zhang Zhongjing made a great contribution to the theory of spleen and stomach from disease prevention, the contraindication, drug usage, aftercare and so on in Treatiseon Febrile Diseases and midcellaneous diseases, which fully shows the academic ideals of strengthening spleen and stomach. Conclusion : Helping to study Treatiseon Febrile Diseases and midcellaneous diseases and understand the thought of Zhang Zhongjing, and gives reference to the theory of spleen and stomach' research in Treatiseon Febrile Diseases and midcellaneous diseases.