• 호남수학학술지
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• 제45권2호
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• pp.269-284
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• 2023

In this paper we study generalizations of the concept of pure-direct-projectivity from module categories to Grothendieck categories. We examine for which categories or under what conditions pure-direct-projective objects are direct-projective, quasi-projective, pure-projective, projective and flat. We investigate classes all of whose objects are pure-direct-projective. We give applications of some of the results to comodule categories.

• 대한수학회지
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• 제57권6호
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• pp.1389-1406
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• 2020

Let Λ be an Artin algebra and mod Λ the category of finitely generated right Λ-modules. We prove that the radical layer length of Λ is an upper bound for the radical layer length of mod Λ. We give an upper bound for the extension dimension of mod Λ in terms of the injective dimension of a certain class of simple right Λ-modules and the radical layer length of DΛ.

• 대한수학회논문집
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• 제10권3호
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• pp.527-539
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• 1995

We consider the Schur groups of some module categories, which are subcategories of category of divisorial modules over a Krull domain. Then we obtain the exact sequence connecting class group, Schur class group and Schur groups of these categories.

• 대한수학회지
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• 제59권4호
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• pp.733-756
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• 2022

In this paper, we introduce the notion of Gorenstein quasiresolving subcategories (denoted by 𝒢𝒬𝓡_𝒳 (𝓐)) in term of quasi-resolving subcategory 𝒳. We define a resolution dimension relative to the Gorenstein quasi-resolving categories 𝒢𝒬𝓡_𝒳 (𝓐). In addition, we study the stability of 𝒢𝒬𝓡_𝒳 (𝓐) and apply the obtained properties to special subcategories and in particular to modules categories. Finally, we use the restricted flat dimension of right B-module M to characterize the finitistic dimension of the endomorphism algebra B of a 𝒢𝒬_𝒳-projective A-module M.

• Korean Journal of Mathematics
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• 제26권3호
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• pp.439-458
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• 2018

In this study, we interpret the notion of homotopy of morphisms in the category of crossed modules in a category C of groups with operations using the categorical equivalence between the categories of crossed modules and of internal categories in C. Further, we characterize the derivations of crossed modules in a category C and obtain new crossed modules using regular derivations of old one.

• 대한수학회지
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• 제60권6호
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• pp.1337-1364
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• 2023

We describe the Gorenstein derived categories of Gorenstein rings via the homotopy categories of Gorenstein injective modules. We also introduce the concept of Gorenstein cosilting complexes and study its basic properties. This concept is generalized by cosilting complexes in relative homological methods. Furthermore, we investigate the existence of the relative version of the Bongartz's theorem and construct a Bongartz's complement for a Gorenstein precosilting complex.

• 대한수학회논문집
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• 제29권1호
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• pp.9-22
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• 2014

In this paper we state some applications of Gr-category theory to the classification problem of crossed modules and to that of group extensions of the type of a crossed module.

• 정보처리학회논문지D
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• 제11D권4호
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• pp.799-808
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• 2004

C 언어가 주로 사용되는 미션 크리티컬 응용 소프트웨어 영역에는 문서화, 간결성, 정확성을 갖는 원시 코드가 요구된다. 본 연구는 XML 기반의 C 원시 코드의 주석관리 체계를 제안한다. 이 주석 관리체계는 주석 사용자 모듈, 검토자 모듈, 주석 추출 모듈, 주석 추적 연계 모듈, 주석 태그 정의 모듈, 저장관리 모들을 포함하는 6개 모듈로 구성된다. 본 연구에서 정의된 XML 주석 태그는 IEEE 표준 1028과 IEEE 표준 1012를 적용하는 개발공정 활동의 범주를 포함한다. C 원시 코드에 주석을 삽입하고 추출하기 위하여 XML 스키마가 사용되며. 주석 추출 결과의 시각적 표시 처리를 위하여 XSL-FO가 사용된다.

• 한국지구과학회:학술대회논문집
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• 한국지구과학회 2005년도 추계학술발표회 논문집
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• pp.304-314
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• 2005

The present study aims to develop animation module-based teaching-learning materials for a unit of middle school 3rd grade science, which contains the movement of the solar system, through the utilization of various forms of multimedia elements. The developed materials consist of 12 in total flash animation modules covering ‘movement of the Earth,’ ‘movement of the Moon,’ movement of the Planets,‘ etc. To analyze the student responses to the science classes to which the developed animation modules were to be applied, the researcher selected for subjects two third-grade classes that were made up of 60 students and later divided for an experimental group and a control group in a middle school located in Jeonju. The experimental group was treated with the animation module-based lessons developed in the present study while the control group was taught in the traditional teacher-centered ways. Tests for the science-related attitudes of the two groups were administered and the results showed that the mean score of the experimental group was significantly higher than the mean score of the control group (p<0.05) in the categories of ‘interest’ and ‘scientific attitude’. It was thus believed that the animation module-based teaching has a positive effect on the categories of ‘interest’ and ‘scientific attitude’. To assess the qualitative dimension of the developed materials, the researcher subjected them to the utilization of the 30 local science teachers and afterwards a survey was done with the 8 crucial items taken from the WBI evaluation test developed by Multimedia Education Support Center in 1998. The result was broadly positive in terms of lesson design and from a technological point of view.

• Korean Journal of Mathematics
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• 제27권1호
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• pp.151-163
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• 2019

The aim of this paper is to consider the categorical equivalence between crossed modules within groupoids and 2-groupoids; and then relate normality and quotient in these two categories.