• Journal of Korean Society of Steel Construction
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• v.18 no.3
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• pp.349-359
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• 2006

This paper presents a new block stiffness matrix for the analysis an orthogonal Cartesian coordinate system. The displacement fields are defined using the first order shear deformable beam theory. The longitudinal displacement can be expressed as the sum of the projected plane deformation of the cross-section due to Timoshenko's beam theory and axial warping deformation due to modified Vlasov's thin-waled beam theory. The derived element takes into account flexural shear deformation and torsional warping deformation. Three different types of beam elements, namely, the two-noded, three-noded, and four-noded beam elements, are developed. The quadratic and cubic elements are found to be very efficient for the flexural analysis of laminated composite beams. The versatility and accuracy of the new element are demonstrated by comparing the numerical results available in the literature.

• Journal of Global Scholars of Marketing Science
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• v.3
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• pp.173-193
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• 1999

본 연구는 소비자의 제품성과 평가에 대한 선행요인을 규명하기 위한 것이다. 기존의 연구 결과에서는 제품성과에 대한 소비자의 사전 기대 신념 수준이 제품 성과 평가에 주요한 원인임을 밝히고 있다. 1980년대부터 소비자행동 및 심리학 분야에서 감정의 역할 및 기타 심리요소와의 관계에 대한 관심이 증대되면서 제품 평가 과정에 있어서 감정이 중요한 요인이 될 수 있음이 밝혀 졌다. 즉, 제품성과 평가에 있어서 소비자의 일시적 측면과 감정적 측면에 모두 영향을 받을 수 있다는 것이다. 그러나 감정에 관련된 인구에 있어서 항상 문제가 되어왔던 부분이 감정의 개념 규정과 특성이다. 현재까지도 이 문제는 여전히 해결해야 할 것이 많지만 이에 대한 새로운 연구 결과가 많이 제시되었다. 본 연구에서는 우선 이론적 고찰을 통하여 소비자 감정 반응의 유형을 구분하고 제품 평가 과정에서 발견되는 감정 반응은 주로 기분 상태의 성질을 띠고 있음을 설명한다. 한편 본 연구와 관련하여 주목할 만한 이론이 감정의 인지적 평가 이론이다. 이 이론의 필자는 개인의 복지에 영향을 미치는 사건에 대한 인지적 평가가 감정에 선행한다는 것이다. 본 연구에서는 감정의 인지적 점포 내 기분 상태의 인지적 평가 요소로 사전적 기대와 점포 평가를 제시하고, 점포 내 기분 상태의 결과로 제품 성과 평가를 제시하는 연구 모형을 수립하였다. 이 연구 모형에 대해 공분산 구조 분석을 실시한 결과 점포 평가가 점포 내 기분 상태의 중요한 인지적 평가 요인이 되었으며, 점포 내 기분 상태의 유쾌 차원이 소비자의 제품 성과 평가에 유의적인 영향을 미치는 것으로 나타났다.

• Computational Structural Engineering
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• v.8 no.3
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• pp.59-66
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• 1995

The dynamic responses of structure under impulsive loading have been investigated according to its duration, based on the theory of viscoplasticity which can appropriately represent the effects of plasticity and rheology simultaneously. The viscoplastic model has been implemented into the two-dimensional finite element system to solve plane stress, plane strain or axi-symmetric problems, and the implicit integration scheme, of which solutions are unconditionally stable for relatively large time step length, has been developed to simulate visoplastic straining with deriving the explicit relationship between stress and strain at a material point level. After simulation, one carefully concludes that the duration as well as magnitude of impulsive loading plays an important role in design of structures.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.3
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• pp.659-666
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• 2015

In this paper, we propose a novel reconstruction method of spatially filtered 3D images in integral imaging based on parallel lens array. The parallel lens array is composed of two lens arrays, which are positioned side by side through longitudinal direction. Conventional spatial filtering method by using convolution property between periodic functions has drawback that is the limitation of the position of target object. this caused the result that the target object should be located on the low depth resolution region. The available spatial filtering region of the spatial filtering method is depending on the focal length and the number of elemental lens in the integral imaging pickup system. In this regard, we propose the parallel lens array system to enhance the available spatial filtering region and depth resolution. The experiment result indicate that the proposed method outperforms the conventional method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.3
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• pp.735-750
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• 1991

본 연구에서는 적층 복합판의 충격 해석을 위하여 Reddy의 고차 전단 변형 이 론에 기초를 두고, 정적 압입 실험에 의한 접촉 법칙을 고려한 동적 유한 요소 해석 (dynamic finite element analysis)을 행하여 충격 실험에 의한 결과와 1차 전단변형 이론에 의한 해와 비교 검토하므로서, 그 유용성과 우수성을 입증하고, 적층 복합재의 충격 응력 및 응력파 전파 특성에 대하여 연구하고자 한다.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.1
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• pp.38-44
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• 2004

An experimental study for a crane hook was performed to investigate the stress distribution along a certain line where the maximum and minimum stresses to be developed. On this line, the isoclinic fringe and/or principal stress direction is constant. The crane hook was modeled into a 2-dimensional plate made of urethane rubber called 'Photoflex' The Photoflex is very sensitive to a load and has low photoelastic fringe constant. The Tardy compensation method with the fringe sharpening process and the 4-step phase shifting method, was used for the photoelastic technique. Experimental results by photoelasticity were compared with the calculated stresses from the simple curved beam theory and tile finite element analysis. Ail the results were close to each other.

• Journal of the Korean Society of Propulsion Engineers
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• v.5 no.4
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• pp.1-11
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• 2001

A theory for time-dependent, high temperature ablation of poroelastic carbon composite insulators is applied using finite element methods to determine material properties from experimental data. The theory contains important revisions to that in Lee, Salamon and Sullivan[1] by making a sharp distinction between Biots constants and permeability and setting both to analytical functions of porosity. The finite element program and material modeling has been modified to (1) more closely adhere to porous-material theory, (2) include a newly discovered analytical simplification and (3) refine the material property descriptions. Application to experimental problems and comparisons with data permit determination of Biots constants and permeability and their evolution with respect to matrix decomposition and clearly show how material parameters affect the material response, e.g., amplitude and the location of peaks with respect to temperature. In particular, the response is very sensitive to permeability and dominated by it.

• 전기의세계
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• v.35 no.12
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• pp.776-781
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• 1986

본고의 내용은 다음과 같다. 1. 공정제어이론 2. 컴퓨터 공정제어시스템의 구성요소 2.1 측정 및 인터페이스(measurement and interface) 2.2 사용자 인터페이스(man-machine interface) 2.3 시스템의 소프트웨어 2.4 통신망(communication network)

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.335-341
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• 2017

In this paper, beam finite elements with higher-order derivatives' continuity are formulated and evaluated for various boundary conditions. All the beam elements are based on Euler-Bernoulli beam theory. These higher-order beam elements are often required to analyze structures by using newly developed higher-order beam theories and/or non-classical beam theories based on nonlocal elasticity. It is however rare to assess the performance of such elements in terms of boundary and loading conditions. To this end, two higher-order beam elements are formulated, in which $C^2$ and $C^3$ continuities of the deflection are enforced, respectively. Three different boundary conditions are then applied to solve beam structures, such as cantilever, simply-support and clamped-hinge conditions. In addition to conventional Euler-Bernoulli beam boundary conditions, the effect of higher-order boundary conditions is investigated. Depending on the boundary conditions, the oscillatory behavior of deflections is observed. Especially the geometric boundary conditions are problematic, which trigger unstable solutions when higher-order deflections are prescribed. It is expected that the results obtained herein serve as a guideline for higher-order derivatives' continuous finite elements.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6B
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• pp.379-385
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• 2012

Recent development of computing power and theoretical advances in computational fluid dynamics have made possible numerical simulations of water waves with full Navier-Stokes equations. In this study, an internal wave maker using the mass source function approach was combined with the level set finite element method for generation of waves. The model is first applied to the two-dimensional linear wave generation and propagation. Then, it is applied to the three-dimensional simulation of the same problem. To effectively utilize computational resources and enhance the speed of execution, parallel algorithms are developed and applied for the three-dimensional problem. The results of numerical simulations are compared with theoretical values and good agreements are observed.