• Computers and Concrete
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• 제12권2호
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• pp.169-186
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• 2013

The aim of this paper is to determine the effect of soil-structure interaction and time dependent material properties on behavior of concrete box-girder highway bridges. Two different finite element analyses, one stage and construction stage, have been carried out on Komurhan Bridge between Elazi$\breve{g}$ and Malatya province of Turkey, over Fırat River. The one stage analysis assume that structure was built in a second and material properties of structure not change under different loads and site conditions during time. However, construction stage analysis considers that construction time and time dependent material properties. The main and side spans of bridge are 135 m and 76 m, respectively. The bridge had been constructed in 3 years between 1983 and 1986 by balanced cantilever construction method. The parameters of soil-structure interaction (SSI), time dependent material properties and construction method are taken into consideration in the construction stage analysis while SSI is single parameter taking into consideration in the one stage analysis. The 3D finite element model of bridge is created the commercial program of SAP2000. Time dependent material properties are elasticity modulus, creep and shrinkage for concrete and relaxation for steel. Soft, medium, and firm soils are selected for evaluating SSI in both analyses. The results of two different finite element analyses are compared with each other. It is seen that both construction stage and SSI have a remarkable effect on the structural behavior of the bridge.

• 조형예술학연구
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• 제5권
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• pp.35-66
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• 2003

This article dealt with the formation and dissolution of tautological structure in the Frank Stella's work from 1959 to 1980 years by the analysis of signifier. A characteristic of Stella's work change is that it has the gradual progress which condensed into three periods -1) the formation and fixation period of tautological structure 2) the relaxation period of tautological structure and 3) the dissolution period of tautological structure. In other words, the early works of stella in the early 1960s has the structure which minimize differences in one hand, and maximize strictness, clearness, and identity on the other hand However, the stella's work from mid 1960s to mid 1970s extend differences gradually, while keeping a characteristic of prior work. And the stella's work after late 1970s has the decentered disintegration, namely anti-tautological structure which maximize differences. 'The formation and dissolution of tautological structure' in the Stella's work could be understood in relation to the fact that the Greenberg's modernist canon has loss the power gradually after late 1960s. That is to say, the dissolution of tautological structure in the late stella's work could be interpreted as the inevitable product which is produced in the searching for a new canon of painting. However, on the other hand, the structural change of stella's work in the late 20th Century is also understood in relation to the broader context, the social, and cultural context. Here, it is interpreted as the one of typical example which reflect a social and cultural convulsion designated as a 'Coming of Postmodernism'. In short, the late Stella's work which emphasize differences and unclearness, while diverging from early Stella's work which stress identity and rationality could be interpreted that it has the homology with the change of ways of thinking in the late 20th century Society.

• 디지털융복합연구
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• 제16권6호
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• pp.105-115
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• 2018

정보통신기술의 발달, 스마트폰의 보편화, 정부의 규제완화 등에 힘입어 모바일 간편 결제서비스가 주요한 금융서비스로 빠르게 성장하고 있다. 이에 본 연구는 모바일 간편 결제서비스 이용의도에 어떤 요인들이 영향을 미치는지를 실증분석을 통해 살펴보고자 하며, 총 386명의 자료를 수집하여 AMOS 22.0을 이용해 분석하였다. 연구결과, 기술적 특성(상대적 이점, 보안성), 개인 특성(자기효능감), 상황적 특성(기존서비스신뢰, 기존서비스만족)이 지각된 가치에 정(+)의 영향을 미치는 것으로 나타났다. 또한, 지각된 가치는 모바일 간편 결제서비스 이용의도에 정(+)의 영향을 미치는 것으로 나타났다. 마지막으로 주관적 규범은 지각된 가치와 모바일 간편 결제서비스 이용의도 간의 관계를 강화하는 것으로 나타났다. 본 연구의 결과는 모바일 간편 결제서비스 관련 기업과 관련 연구 분야에 유용한 정보를 제공할 수 있을 것으로 기대한다.

• 터널과지하공간
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• 제11권2호
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• pp.174-181
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• 2001

지하채굴로 생성된 공동이 충전되지 않은 상태로 있으면 공동 천반의 이완과 붕락에 의해 지반침하 및 지표함몰이 발생한다. 특히, 채굴적 상부에 구조물이 건축될 경우 구조물의 안정성에 심각한 영향을 미친다. 본 연구는 A 채광 지역 채굴적의 충전상태 및 채굴적 분포상황을 조사하기 위해 시추조사와 시추공 카메라 조사를 수행하였으며, 표준관입시험을 통해 암반의 물성 및 지반의 지지력을 측정하였다. 또한 전산해석 프로그램(FLAC)을 이용해 채굴적 상부에 구조물이 구축될 경우 발생하는 지반침하 및 지반침하가 구조물의 안정성에 미치는 영향을 조사하였다. 지반조사 결과 채굴적은 대부분 전석이나 광미(tailing)등과 같은 물질로 충전된 상태였고, 충전물의 공학적 분류는 SM에 속했다. 측정 자료를 근거로 실시한 전산해석 결과충전된 채굴적 상부에 구조물이 구축될 경우 구조물 및 지반의 안정성에 는 큰 문제가 없는 것으로 조사되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.2004-2006
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• 1996

A thermally driven polysilicon micro actuator has been fabricated using surface micromachining techniques. It consists of P-doped polysilicon as a structural layer and TEOS (tetracthylorthosilicate) as a sacrificial layer. The polysilicon was annealed for the relaxation of residual stress which is the main cause to its deformation such as bending and buckling. And the newly developed HF VPE (vapor phase etching) process was also used as an effective release method for the elimination of sacrificial TEOS layer. The thickneas of polysilicon is $2{\mu}m$ and the lengths of active and passive polysilicon cantilevers are $500{\mu}m$ and $260{\mu}m$, respectively. The actuation is incurred by die thermal expansion due to the current flow in the active polysilicon cantilever, which motion is amplified by lever mechanism. The moving distance of polysilicon micro actuator was experimentally conformed as large as $21{\mu}m$ at the input voltage level of 10V and 50Hz square wave. The actuating characteristics are investigated by simulating the phenomena of heat transfer and thermal expansion in the polysilicon layer. The displacement of actuator is analyzed to be proportional to the square of input voltage. These micro actuator technology can be utilized for the fabrication of MEMS (microelectromechanical system) such as micro relay, which requires large displacement or contact force but relatively slow response.

• Asian-Australasian Journal of Animal Sciences
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• 제18권7호
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• pp.933-941
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• 2005

To develop a functional cDNA chip, specific genes expressed in the tissues of swine Kagoshima Berkshire were screened. A total of 4,434 ESTs were obtained by constructing a cDNA library from total RNA isolated from the muscle and fat tissues, affirming their functions by investigating similarity of nucleotide sequences with the database at the NCBI. Among them, 1,230 ESTs were confirmed as novel genes, which, to date, have not been identified. Attaching the genes to a cDNA microarray slide revealed expression patterns of genes in muscle and fat according to the growth stages of swine. As specific genes expressed in the muscle tissues of swine with body weight of 30 kg, 60 genes including actin, myosin, tropomysin, transfer RNA-trp synthetase, Kel-like protein 23, KIAA0182 and COI, Foocen-m, etc were obtained. In addition, 18 novel genes were obtained. As specific genes expressed in fat tissues of swine with body weight of 30 kg, 47 genes including annexin II, Collagen, Fibronectin, Pleckstrin homology domain, serine protease, etc were obtained. 21 novel genes were also obtained. The genes specifically expressed in the muscle and fat tissues of swine affect contraction and relaxation of the muscle and the fat. However, studies on the expression mechanisms of the genes are insufficient. To reveal species of structural genes in swine muscle and fat tissue, interrelation studies in expression and function of genes by using the cDNA chip should be conducted.

• 한국재료학회지
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• 제16권4호
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• pp.241-247
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• 2006

Structural studies have been performed on precipitation hardening discovered in $L1_2-ordered\;Ni_3(Al,Cr)$ containing 0.2 to 3.0 mol% of carbon using transmission electron microscopy (TEM). Fine octahedral precipitates of $M_{23}C_6$ appeared in the matrix by aging at temperatures around 973 K after solution treatment at 1423 K. TEM examination revealed that the $M_{23}C_6$ phase and the matrix lattices have a cube-cube orientation relationship and keep partial atomic matching at the {111} interface. After prolonged aging or by aging at higher temperatures, the $M_{23}C_6$ precipitates then adopt a rod-like morphology elongated parallel to the <100> directions. Deformation at temperature below 973 K, typical Orowan loops were observed surrounding the $M_{23}C_6$ particles. At higher deformation temperatures, the Orowan loops disappeared and the morphology of dislocations at the particle-matrix interfaces suggested the existence of attractive interaction between dislocations and particles. The change of the interaction modes between dislocation and particles with increasing deformation temperature can be considered as a result of strain relaxation at the interface between matrix and particles.

• The Korean Journal of Physiology and Pharmacology
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• 제24권6호
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• pp.529-543
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• 2020

In contrast to ventricular myocytes, the structural and functional importance of atrial transverse tubules (T-tubules) is not fully understood. Therefore, we investigated the ultrastructure of T-tubules of living rat atrial myocytes in comparison with ventricular myocytes. Nanoscale cell surface imaging by scanning ion conductance microscopy (SICM) was accompanied by confocal imaging of intracellular T-tubule network, and the effect of removal of T-tubules on atrial excitation-contraction coupling (EC-coupling) was observed. By SICM imaging, we classified atrial cell surface into 4 subtypes. About 38% of atrial myocytes had smooth cell surface with no clear T-tubule openings and intracellular T-tubules (smooth-type). In 33% of cells, we found a novel membrane nanostructure running in the direction of cell length and named it 'longitudinal fissures' (LFs-type). Interestingly, T-tubule openings were often found inside the LFs. About 17% of atrial cells resembled ventricular myocytes, but they had smaller T-tubule openings and a lower Z-groove ratio than the ventricle (ventricular-type). The remaining 12% of cells showed a mixed structure of each subtype (mixed-type). The LFs-, ventricular-, and mixed-type had an appreciable amount of reticular form of intracellular T-tubules. Formamide-induced detubulation effectively removed atrial T-tubules, which was confirmed by both confocal images and decreased cell capacitance. However, the LFs remained intact after detubulation. Detubulation reduced action potential duration and L-type Ca²⁺ channel (LTCC) density, and prolonged relaxation time of the myocytes. Taken together, we observed heterogeneity of rat atrial T-tubules and membranous ultrastructure, and the alteration of atrial EC-coupling by disruption of T-tubules.

• 문화기술의 융합
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• 제9권4호
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• pp.537-542
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• 2023

최근 도심지 주변으로 집중되는 신축구조물 및 공동구 확장 등과 같은 인접굴착공사로 인해 운영중인 철도 구조물의 변형이 발생되고 있다. 그러나 대부분 구조물에 대한 구조검토 및 보수보강에 집중되고 있으며 궤도에 대한 검토는 부족한 실정이다. 특히 토공노반 상 자갈궤도의 경우 노반과 도상자갈이 강결된 구조가 아니므로, 미소한 수준의 변형으로도 도상자갈 이완현상이 발생할 수 있다. 이는 침목 지지조건이 불안정한 조건으로 유도될 수 있으므로 충분한 안전성을 확보해야한다. 또한 불안정한 지지조건으로 열차탈선의 위험이 매우 높은 궤도형식이다. 따라서 본 연구에서는 노반 변형에 따른 자갈궤도의 변형특성과 궤도지지성능의 상관관계를 실험 및 해석적으로 입증하고, 자갈궤도의 상태 및 궤도지지강성을 평가할 수 있는 평가기법을 제시하고자 한다.

• 한국컴퓨터정보학회논문지
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• 제25권10호
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• pp.211-219
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• 2020

본 연구는 일정기간 여성들에게 체형관리를 실시하여 생활습관, 사회적 지지, 생활만족도의 잠재변수 간 구조적 관계와 삶의 질에 미치는 영향을 파악하는 것이다. 체형관리는 카이로프랙틱 교정법과 근막이완요법으로 시술이 진행되었고, 25년 경력을 소지한 물리치료사를 전문가로 활용하였다. 연구대상자는 광주광역시에 거주하는 20대에서 60대 사이의 여성을 표본으로 하였고, 연구를 위해 체형관리 시술을 20회 이상 참여한 여성에게 설문지를 자가 평가 기입법으로 작성하게 하여 그 중 설문 응답이 정확하고 자료 분석하기에 타당하게 이루어진 100명을 최종 분석 대상으로 하였다. 연구결과 여성의 건강관련 삶의 질은 체형관리 유무와 정도에 따라 삶의 질이 달라질 수 있다는 것을 알 수 있었다. 또한 생활습관과 사회적 지지도의 정도에 따라 삶의 만족도는 달라지고 삶의 질과 관련된 잠재변수들 간의 직접효과, 간접효과, 총 효과 모두 유의미한 것으로 나타났다. 본 연구에서는 여성의 삶의 질을 향상시킬 수 있는 평소의 체형관리가 여성 스스로 바람직한 생활습관을 갖도록 하는 계기와 삶의 질을 중요시하는 인식을 갖게 해주는 것에 의미를 부여한다.