• 대한수학회보
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• 제48권2호
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• pp.365-375
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• 2011

In this paper, we study w-ity and (co-)semi-divisoriality of Hom-modules and the semi-divisorial envelope of $Hom_R$(M,N) under suitable conditions on R, M, and N. We also investigate an injective cogenerator of a quotient category.

• 대한수학회보
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• 제38권1호
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• pp.137-142
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• 2001

In this paper, we initiate the study of some annihilator conditions on polynomials which were used by Kaplansky [4] to abstract algebras of bounded linear operators on a Hilbert spaces with Baer condition. On the other hand, p.p. rings were introduced by A. Hattori [3] to study the torsion theory. The purpose of this paper is to introduce near-rings with Baer condition and near-rings with p.p. condition which are somewhat different from the ring case, and to extend a results of Armendarz [1] to polynomial near-rings with Baer condition in somewhat different way of Birkenmeier and Huang [2].

• 대한수학회논문집
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• 제35권4호
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• pp.1075-1085
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• 2020

We investigate the relation between the notion of e-exactness, recently introduced by Akray and Zebary, and some functors naturally related to it, such as the functor P : Mod-R → Spec(Mod-R), where Spec(Mod-R) denotes the spectral category of Mod-R, and the localization functor with respect to the singular torsion theory.

• 대한수학회논문집
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• 제14권2호
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• pp.287-293
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• 1999

In this paper, we give an affirmative answer to the question raised in [5]; whether L((P)) is principal or not. Using this fact, we try to give concrete form of module of quotient with respect to a torsion theory determined by L((P)).

• Structural Engineering and Mechanics
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• 제75권3호
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• pp.401-414
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• 2020

Unlike the existing truss models for shear and torsion analysis, in this study, the torsional capacities of reinforced concrete (RC) members were estimated by introducing multi-potential capacity criteria that considered the aggregate interlock, concrete crushing, and spalling of concrete cover. The smeared truss model based on the fixed-angle theory was utilized to obtain the torsional behavior of reinforced concrete member, and the multi-potential capacity criteria were then applied to draw the capacity of the member. In addition, to avoid any iterative calculation in the existing torsional behavior model, a simple strength model was suggested that considers key variables, such as the effective thickness of torsional member, principal stress angle, and strain effect that reduces the resistance of concrete due to large longitudinal tensile strain. The proposed multi-potential capacity concept and the simple strength model were verified by comparing with test results collected from the literature. The study found that the multi-potential capacity could estimate in a rational manner not only the torsional strength but also the failure mode of RC members subjected to torsional moment, by reflecting the reinforcing index in both transverse and longitudinal directions, as well as the sectional and material properties of RC members.

• 대한토목학회논문집
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• 제8권2호
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• pp.125-133
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• 1988

RC 부재(部材)에 대한 정밀도 높은 하중이력곡선(荷重履歷曲線)의 제안은 합리적인 설계법(設計法)의 수립이라는 관점으로 볼 때 매우 중요하다. 순수비틀림을 받는 RC 부재(部材)의 비틀림모멘트와 비틀림각(角) 관계곡선을 최근 제안한 사람은 Collins, Hsu 등이다. 그러나 그의 비틀림 내력평가(耐力評價) 결과는 극한상태를 제외하고는 모든 하중영역(荷重領域)에 있어서 상당히 과소평가되고 있다. 본 연구에서는 구성방정식(構成方程式)에 콘크리트의 인장강성(引張剛性) 및 수정된 콘크리트 softening 계수(係數)를 도입하여 임의의 하중단계에서도 비틀림내력(耐力)의 정밀도를 높이는데 그 목적(目的)을 두었다. 특히 이론해석(理論解析)의 타당성을 검토하고자 14체(體)의 RC 부재(部材)를 제작하여 재하실험(載荷實驗)을 실시하였다.

• Composites Research
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• 제14권6호
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• pp.9-15
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• 2001

본 연구에서는 복합재료로 만들어진 박판의 상자형 보에 대만 선형 정적해석을 수행하였다. 복합재료 보의 해석을 위해서 혼합 보 이론을 적용하였으며, 상자형 단면의 벽에 대해 설정이 가능한 여러 가지 구성방정식을 고려할 수 있도록 하였다. 굽힘-비틀림 혹은 인장-비틀림 연성을 갖는 단순한 적층 형상의 복합재료 강자형 보를 예로 들어 보의 정적 거동에 미치는 복합재료의 연성효과를 고찰하였다. 본 해석결과의 타당성을 검증하기 위만 방편으로 상용 구조해석 프로그램을 이용한 정밀 유한요소 구조해석을 수행하였다. 혼합 보 이론을 이용하여 복합재료 상자형 보에 대한 단면상수 등을 해석적으로 결정하였으며, 적절한 구성방정식의 설정 여부가 최종적인 해의 정확도를 결정하는 중요한 요소임을 보였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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• pp.3-10
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• 2002

Recently, arches are used structurally because of their high in-plane stiffness and strength, which result from their ability to transmit most of the applied loading by axial forces actions, so that the bending actions are reduced. On the other hand, the resistances of arches to (out-of-plane,) flexural-torsional behavior depend on the rigidities EI/sub y/, for lateral bending, GJ for Uniform torsion, and EI/sub w/ for warping torsion which are related to axial stress for flexural-torsional behavior. The resistance of an arch to out-of-plane behavior may be reduced by its in-plane curvature, and so it may require significant lateral bracing. Thus. it is supposed that In-plane preloading which cause an axial stress, have an effect on out-of-plane free vibration behavior of arches. Because axial stresses caused increase or decrease out-of-plane stiffness. But study about this substance is insufficient. In this thesis, We will study an effect of preloading on lateral free vibration of arches, using finite element method based on Kang and Yoo's curved beam theory (about curved beam element have 7 degree of freedom including warping) with FORTRAN programming.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.281-284
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• 2006

ASCE-ACI Committee 426 and 445, on Shear and Torsion, well noted in their report that recent research work regarding shear and torsion had been devoted primarily to members. But it was not logical approach of PSC members applied by axial force based on the shear deformation in web element. And it was not included that the effect of axial is to shift the shear strain(or crack width) in the web element versus the applied shear curve up or down by the amount by which the biaxial tension-compression state varies. The shear strength also increases or decreases, so that the change in shear strain at service load due to the presence of axial load is to some extent changed. Generally, in corresponding beams the shear strain at service load is less in the beam subject to axial compression and greater in the beam subject to axial tension, than in the beam without axial load. In particular, however, no research were available on the shear deformation in shear of PSC members with web reinforcement, subject to axial force in addition to shear and bending. Therefore, this study was basically performed to develop the program for the calculation of the shear deformation based on the shear effect of axial force in prestressed concrete members.

• Nuclear Engineering and Technology
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• 제55권4호
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• pp.1485-1494
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• 2023

The bow of the nuclear fuel assembly is a well-known phenomenon. One of the vital criteria during the history of nuclear fuel development has been fuel assembly's mechanical stability. Once present, the fuel assembly bow can lead to safety issues like excessive water gap and power redistribution or even incomplete rod insertion (IRI). The extensive bow can result in assembly handling and loading problems. This is why the fuel assembly's bow is one of the most often controlled geometrical factors during periodic fuel inspections for VVER when compared e.g. to on-site fuel rod gap measurements or other instrumental measurements performed on-site. Our proposed screening method uses existing video records for fuel inspection. We establish video frames normalization and aggregation for the purposes of bow measurement. The whole process is done by digital image processing algorithms which analyze rotations of video frames, extract angles whose source is the fuel set torsion, and reconstruct torsion schema. This approach provides results comparable to the commonly utilized method. We tested this new approach in real operation on 19 fuel assemblies with different campaign numbers and designs, where the average deviation from other methods was less than 2 % on average. Due to the fact, that the method has not yet been validated during full scale measurements of the fuel inspection, the preliminary results stand for that we recommend this method as a complementary part of standard bow measurement procedures to increase measurement robustness, lower time consumption and preserve or increase accuracy. After completed validation it is expected that the proposed method allows standalone fuel assembly bow measurements.