• Geomechanics and Engineering
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• v.1 no.1
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• pp.97-112
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• 2009

The interactions between a granular pile and raft placed on top are investigated using the continuum approach. The compatibility of vertical and radial displacements along the pile - soil interface and of the vertical displacements along the raft - top of ground interfaces are satisfied. Results show that consideration of radial displacement compatibility does not influence the settlement response of or sharing of the applied load between the granular pile and the raft. The percentage load carried by the granular pile (GP) increases with the increase of its stiffness and decreases with the increase of the relative size of raft. The normal stresses at the raft - soil interface decrease with the increase of stiffness of GP and/or relative length of GP. The influences of GP stiffness and relative length of GP are found to be more for relatively large size of raft. The percentage of load transferred to the base of GP increases with the increase of relative size of raft.

• Journal of Applied Reliability
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• v.3 no.1
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• pp.1-12
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• 2003

A continuum structure function(CSF) is a non-decreasing mapping from the unit hypercube to the unit interval. A Barlow-Wu type CSF is a CSF whose behaviour is modeled by its underlying binary structure, which is based on the multistate structure functions suggested by Barlow and Wu(1978). As the measures of importance of a system component for a Barlow-Wu type CSF, the structural and reliability importance of a component at system level ${\alpha}$ (0< ${\alpha}$ <1) are defined and their properties are deduced. Computational results are discussed as well for illustrative purpose.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.417-421
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• 2015

We analyzed 0.5-45 keV data of NGC 3227 observed by Suzaku six times between 2008 October 28 and December 2. The count-count plot between the 0.5-3 keV and 3-10 keV bands exhibits a clear break, separating the data into bright and faint phases. Applying the difference spectrum method and time-averaged spectral fits to the phase data, we found the presence of two kinds of variable primary X-rays, (1) a hard primary component with ${\Gamma}{\sim}1.7$ dominating in the faint phase and (2) a soft primary continuum with ${\Gamma}{\sim}2.4$ appearing in the bright phase, both affected by partial absorption. Considering their timing and spectral characteristics, component (1) is presumably identical to a Compton continuum in the low/hard state, while component (2) may correspond to the hard tail emission in the high/soft state, or compact-jet emission. In that case, an accretion ow onto the central super massive black hole in NGC 3227 can be interpreted to include the two different states.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.87.2-87.2
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• 2012

The HI absorption against bright continuum source provides a unique opportunity to measure spin temperature of the neutral hydrogen gas. We find three cases among the sample of the VIVA (VLA Imaging of Virgo galaxies in Atomic gas) study with self absorption of strong central continuum by galactic HI gas. Using the HI flux ratio of emission and absorption, we constrain the spin temperature of the neutral hydrogen gas on their disk. The HI absorption is marginally resolved in these galaxies, which also allows us to probe the kinematics of the absorbing gas. All three galaxies are severely stripped in HI due to the intra cluster medium (ICM). We discuss the influence of environmental processes on the temperature and kinematics of HI in these galaxies.

• Journal of Information Display
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• v.4 no.1
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• pp.24-28
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• 2003

We studied the anchoring properties in photo-aligned periodic domains of liquid crystals (LCs) in an alternating homeotropic and hybrid geometry. In this geometry, the surface anchoring energy was determined in using the director-distorted length of the LC near domain boundary, calculated in a linear approximation of the director profile within the continuum theory. The measurements were made using the LC diffraction grating with the phase profile in the form of a trapezoid.

• Journal of Ocean Engineering and Technology
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• v.14 no.2
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• pp.70-75
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• 2000

In this paper a new constitutive model for ductile materials was proposed. This model can describe the material degradation due to the evolution of isotropic damage during elasto-platic deformation. The plastic flow rule was derived under the framework of thermodynamic approach of continuum damage mechanics(CDM) in which plastic strain hardening parameters and isotropic damage were taken as thermodynamic state variables. And the process to determine material constants for constitutive model using an experimental data was presented.

• Journal of Ocean Engineering and Technology
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• v.14 no.2
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• pp.76-83
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• 2000

this paper was concentrated on the finite element formulation to solve boundary value problems by using the isotropic elasto-plastic damage constitutive model proposed previously(Noh, 2000) The plastic damage of ductile materials is generally accompanied by large plasticdeformation and strain. So nonlinearity problems induced by large deformation large rotation and large strain behaviors were dealt with using the nonlinear kinematics of elasto-plastic deformations based on the continuum mechanics. The elasto-plastic damage constitutive model was applied to the nonlinear finite element formulation process of Shin et al(1997) and an improved analysis model considering the all nonlinearities of structural behaviors is proposed. Finally to investigate the applicability and validity of the numerical model some numerial examples were considered.

• Interaction and multiscale mechanics
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• v.7 no.1
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• pp.525-542
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• 2014

The state-based peridynamics is considered a nonlocal method in which the equations of motion utilize integral form as opposed to the partial differential equations in the classical continuum mechanics. As a result, the enforcement of boundary conditions in solid mechanics analyses cannot follow the standard way as in a classical continuum theory. In this paper, a new approach for the boundary condition enforcement in the state-based peridynamic formulation is presented. The new method is first formulated based on a convex kernel approximation to restore the Kronecker-delta property on the boundary in 1-D case. The convex kernel approximation is further localized near the boundary to meet the condition that recovers the correct boundary particle forces. The new formulation is extended to the two-dimensional problem and is shown to reserve the conservation of linear momentum and angular momentum. Three numerical benchmarks are provided to demonstrate the effectiveness and accuracy of the proposed approach.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.322-324
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• 2003

Leaf C:N ratio is a new factor in the field of biochemical inversion with hyperspectral data. Effects of common-used spectral transformations including log(R), log(1/R), 1/R, etc. from 400nm to 2490nm on its inversion are compared. Results show that their effects on statistical modeling are not apparent. Continuum removal is used on original reflectance in the range of 2030nm to 2220nm, in which exists an apparent absorption peak due to cellulose, lignin, protein, etc. The effect is distinctive and tends to improve the precision of C:N ratio inversion. Further, it is a robust and physically based transformation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.135-138
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• 2005

HDL(Hardware Description Language) is the most important modem tools used to describe hardware, and becomes important as we move to higher levels of abstraction. The HDL has been made brisk use of in analog design, MEMS device[1-2], process related field as well as digital design. The most important characteristics of HDL is Abstraction which is the strongest tool that extend greatly designer's design ability. In this paper by the Modelling Continuum with hierarchical structure of abstraction, we apply UML(Unified Modeling Language) to SoC Design with HDL UML makes an easy and visual description of the various levels of abstraction, and gives designers good flexible modeling capabilty for SoC Design.