• 한국세라믹학회지
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• 제51권5호
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• pp.516-521
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• 2014

This paper describes the development of a new piezoelectric unimorph cantilever structure intended to improve electrical output power, compared to a conventional cantilever. The proposed structure employs a cylindrical bar attached to one side of a steel plate, which is a significant factor in forced vibration mode. The feasibility of the proposed methodology was assessed experimentally and theoretically. The influence of three different types of bar material (i.e., stainless steel, silicon rubber, and urethane), and bar position, on the output voltage were examined and compared with those without the bar. The optimal position and material for the bar were identified through experimental and theoretical analyses. It appears that the electrical output power of the proposed cantilever is about 40% higher than that of a conventional unimorph cantilever.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.278-280
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• 2013

To minimize construction quantity of nuclear facility, it is required to reduce reinforcing bar amount and solve reinforcing bar concentration and for this, it is necessary to develop application design technology and modular of high strength reinforcing bar. Hence, KHNP reduces excessive reinforcing bar amount which can cause possibility of poor construction of concrete through design standard development and modular of nuclear facility structure using high strength reinforcing bar to raise economics and has its purpose to maintain high-level safety and durability as they are.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.17-18
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• 2013

To minimize construction of nuclear facility, it is required to reduce reinforcing bar amount and solve reinforcing bar concentration and for this, it is necessary to develop appication design technology and modular of high strength reinforcing bar. Hence, KHNP reduces excessive reinforcing bar amount which can cause possibility of poor construction of concrete through design standard development and modular of nuclear facility structure using high strength reinforcing bar to raise economics and has its purpose to maintain high-level safety and durability as they are. This study is to introduce application method for the Rebar Modulation of High-Strength Reinforcing Bars to the Nuclear Power Plant Structures.

• Journal of Advanced Marine Engineering and Technology
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• 제36권4호
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• pp.467-475
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• 2012

이 논문에서는 비틈 봉을 기반으로 한 중력보상기가 적용된 새로운 외력증강기를 이용하여 인체 다리관절에 작용하는 부하를 경감시키는 방법에 대해 제안한다. 비틈 봉 특성을 추정하고 측정하기 위하여 설계와 구조 해석을 행하였다. 설계와 구조해석을 바탕으로 매우 경량이고 소형인 새로운 외력증강기를 개발하였다. 구조해석은 외력증강기를 매우 경량으로 하기위해 최적두께의 링크에 대한 FEM해석을 행하였다.

• 한국기계가공학회지
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• 제19권5호
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• pp.27-37
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• 2020

Structural optimization problems with discrete design variables require more function calculations (or finite element analyses) than those in the continuous design space. In this study, a method to find an optimal solution in the discrete design of the truss structure is presented, reducing the number of function calculations. Because a continuous optimal solution is the Karush-Kuhn-Tucker point that satisfies the optimality condition, it is assumed that the discrete optimal solution is around the continuous optimum. Then, response values such as weight, displacement, and stress are predicted using approximate models-referred to as hybrid metamodels-within specified design ranges. The discrete design method using the hybrid metamodels is used as a post-process of the continuous optimization process. Standard truss design problems of 10-bar, 25-bar, 15-bar, and 52-bar are solved to show the usefulness of this method. The results are compared with those of existing methods.

• 헤리티지:역사와 과학
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• 제45권3호
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• pp.4-27
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• 2012

요대(遼代)에는 오경(五京)이 설치되었다. 요(遼)의 상경(上京)이 수도이고 중경(中京)은 배도(陪都)이며, 다른 세 곳은 상징적 의미의 경성(京城)이다. 상경은 '일(日)'자형 구조로 중국 고대 도성제도의 새로운 모델이다. 중경은 여러 겹으로 둘러싸인 배치형태로 변량성(?梁城) 등의 영향을 받은 것이다. 남경과 서경, 동경의 3경은 당(唐) 혹은 발해(渤海) 구성(舊城)의 기초 위에 개축한 것으로 원래의 도시 구조를 이용하였다. 요 상경의 구조와 계획은 금(金), 원(元), 청(淸)의 도성 구조에 상당히 중요한 영향을 주었다. 요(遼), 송(宋), 금(金), 원(元), 명(明) 등의 왕조에서는 다수의 경(京)이나 도(都)를 설치하였으며 대부분은 배도(陪都)의 성격을 지니고 있다. 요대(916~1125년)에는 오경이 설치되었는데, 상경(上京) 임황부(臨潢府, 현 내몽고 파림좌기[巴林左旗] 임동진[林東鎭] 남쪽)는 요나라의 수도이고, 그 외에 동경(東京) 요양부(遼陽府, 현 요녕성 요양[遼陽]시 인근), 남경(南京) 석진부(析津府, 현 북경 광안문[廣安門] 밖 선무구[宣武區] 일대), 중경(中京) 대정부(大定府, 현 내몽고 영성[寗成]현 철장영자[鐵匠營子]), 서경(西京) 대동부(大同府, 현 대동시) 등이 있다. 본고에서는 계획이념과 형태구조 그리고 주요 배치 형태 등을 중심으로 요대 오경의 유형과 형태구조에 대한 기초적인 고찰을 하고자 한다.

• Steel and Composite Structures
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• 제18권6호
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• pp.1391-1404
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• 2015

A radially retractable roof structure based on the concept of the hybrid grid shell is proposed in this paper. The single-layer steel trusses of the radially foldable bar structure are diagonally stiffened by cables, which leads to a single-layer lattice shell with triangular mesh. Then comparison between the static behavior between the retractable hybrid grid shell and the corresponding foldable bar shell with quadrangular mesh is discussed. Moreover, the effects of different structural parameters, such as the rise-to-span ratio, the bar cross section area and the pre-stress of the cables, on the structural behaviors are investigated. The results show that prestressed cables can strengthen the foldable bar shell with quadrangular mesh. Higher structural stiffness is anticipated by introducing cables into the hybrid system. When the rise-span ratio is equal to 0.2, where the joint displacement reaches the minimal value, the structure shape of the hyrbid grid shell approaches the reasonable arch axis. The increase of the section of steel bars contributes a lot to the integrity stiffness of the structure. Increasing cable sections would enhance the structure stiffness, but it contributes little to axial forces in structural members. And the level of cable prestress has slight influence on the joint displacements and member forces.

• Smart Structures and Systems
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• 제24권2호
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• pp.193-207
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• 2019

This study concerns with morphing structures, e.g. as applied in the aerospace industry. A morphing aerofoil structure capable of variable geometry was developed, which was shown to be able to cater for the different aerodynamic requirements at different stages of flight. In this work, the useful and relatively simple method has been applied, which provides a direct method for calculating required morphing shape displacements via finding the most effective bar through calculating bar sensitivity to displacement and calculating set of length actuations for bar assembly to control/adjust shape imperfection of prestressable structural assemblies including complex elements ("macro-elements", e.g., the pantographic element), involving Matrix Condensation. The technique has been verified by experiments on the physical model of an aerofoil shaped morphing pantographic structure. Overall, experimental results agree well with theoretical prediction. Furthermore, the technique of multi-iteration adjustment was presented that effective in eliminating errors that occur in the practical adjustment process itself. It has been demonstrated by the experiments on the physical model of pantographic morphing structure. Finally, the study discusses identification of the most effective bars with the objective of minimal number of actuators or minimum actuation.

• 대한수학회논문집
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• 제34권2호
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• pp.615-632
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• 2019

We study generic lightlike submanifolds M of an indefinite trans-Sasakian manifold ${\bar{M}}$ or an indefinite generalized Sasakian space form ${\bar{M}}(f_1,f_2,f_3)$ endowed with an $({\ell},m)$-type metric connection subject such that the structure vector field ${\zeta}$ of ${\bar{M}}$ is tangent to M.

• 한국의사학회지
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• 제22권2호
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• pp.15-22
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• 2009

In this thesis, the emphasis is laid especially on the culture & structure of Huizhou Province, China as the prime mover of the specifically-regional Huizhou $X{\bar{i}}n^{\prime}{\bar{a}}n$ medicine. Huizhou was the home town & stronghold of Neo-coufucian masters Cheng-Zhu (Cheng brothers and Zhu-hsi)". The tradition of the region as "The arts province" resulted in the flourishing trend of nurturing prominent Confucian-doctors. The remarkable all round activities of Huizhou Merchants (新安商人 $X{\bar{i}}n^{\prime}{\bar{a}}nsh{\bar{a}}ngr{\acute{e}}n$), as the reigning power merchant at the period were the second mover of the Zeitgeist. Their nation-wide network all over China made it possible to gain valuable inlormation and access to news including the field of medicine in time. Some merchants actually have "abandoned their own jobs to become doctors of medicine". This Confucian-Merchant culture was one of intrinsic characteristics of Huizhou region, inducing "Pragmatic Scholarship". With the enlargement of the population of Confucian-tumed doctors and improvement of the societal status of doctors, the resultant occupational triad of local Confucian govemment officials, local $X{\bar{i}}n^{\prime}{\bar{a}}nsh{\bar{a}}ngr{\acute{e}}n$ merchants, and local doctors was established after the Middle-Ming Dynasty. Ultimately, the two prime movers of the concomitant development of medicine in the Province Huizhou in this study are concluded to be the synergy effects of the Neo-Confucian tradition and economic power of the prevalent Huizhou Merchants ($X{\bar{i}}n^{\prime}{\bar{a}}nsh{\bar{a}}ngr{\acute{e}}n$).