• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1355-1360
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• 2011

The interaction between the cell and the substrate is the most prominent feature affecting the migration of a crawling cell. This paper proposes a three-dimensional dynamic model using the diffuse interface description that reveals the effects of the interaction between a single crawling cell and the substrate during chemotactic migration. To illustrate the effects of interaction between the cell and the substrate, we consider the interfacial energy between the coexistent materials. Multiple mechanisms including the interface energy, chemotaxis effect, and diffusion, are addressed by employing a diffuse interface model.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.173-178
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• 2020

A multi-ray model has been used to interpret radio transmission losses in half-canyon structures with slope and to formulate a multi-ray propagation model depending on the angle of slopes. The cut-off angles for the third and fourth paths, which are the slope-sided reflection paths of the transmission and reception radio waves determined by the inclined angles of the slope, were calculated with the height and location of the transmitter and receiver. To predict transmission losses in an inclined plane environment, the embankment environment where the actual slope exists was modeled and simulated to calculate the loss of propagation transmission, and the radio wave transmission loss was confirmed by the measurement for the frequency band 1 to 6 GHz. Simulation results and measurement results showed similar trends in radio transmission loss, and radio transmission loss predictions and measurement results for various terrain information can be used in the design of radio propagation service.

• Journal of Satellite, Information and Communications
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• v.7 no.2
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• pp.67-71
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• 2012

This paper represents the impact analysis results of antenna reflector for the UHF-band antenna of Space Launch Vehicle. Three types of UHF-band antenna reflector model have been proposed and simulated to compare their characteristics such as resonance frequency, reflection loss and radiation pattern etc. Simulation results showed that resonance frequency and return loss of each reflector models were rarely affected even if reflector sizes are changed. The antenna gain and 3dB bandwidth were slightly changed to the worse directions as the reflector sizes are smaller.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.2 s.40
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• pp.3-14
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• 2007

This study proposes an automatic method to generate 3D building models using a draft map, which is an intermediate product generated during the map generation process based on aerial photos. The proposed method is to generate a terrain model, roof models, and wall models sequentially from the limited 3D information extracted from an existing draft map. Based on the planar fitting error of the roof corner points, the roof model is generated as a single planar facet or a multiple planar structure. The first type is derived using a robust estimation method while the second type is constructed through segmentation and merging based on a triangular irregular network. Each edge of this roof model is then projected to the terrain model to create a wall facet. The experimental results from its application to real data indicates that the building models of various shapes in wide areas are successfully generated. The proposed method is evaluated to be an cost and time effective method since it utilizes the existing data.

• Journal of Korean Society of Steel Construction
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• v.15 no.5 s.66
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• pp.509-518
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• 2003

In this study, we carried out nonlinear analysis according to various interface nonlinear models by interaction magnitude, and analyzed interface behavior such as distribution of tangential traction and relative slip in steel-concrete composite structure. As a result of this study, tangential traction and relative slip of interface is rapidly increased at the steel plate-concrete interface, especially at the neutral region, rather than tensile, as opposed to the T beam-concrete interface. In transverse direction, it has gradually reduced to go outside from loading position. In longitudinal direction, it was minimum at the central region near the loading point, maximum at 0.6-0.7L from support and gradually reduced as it nears support. Moreover, as the load is increased, the failure of interface gradually expands from the maximum tangential traction position to the entire region. It is expected to provide fundamentality for interface behavior and load-carrying mechanism, and for the design of bending and shear connection of steel-concrete composite structure.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.2
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• pp.30-37
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• 1992

Since a ship is a complex steel construction which consists of sculptured surfaces and inner surface members, a high technique of information modeling is indispensable to describe the form of hull surface and steel structure members consistently. A model contains both topological and geometrical information of the structural members. Therefore, the hull form should be represented by the wireframe of surface model so that the accuracy in each design stage is satisfied. The structural members like plane surfaces, stiffeners and the relations between such members are to be described systematically in data base. A collection of the data stored in database is a model to be built. The model will be used not only to generate the drawings and documents for ship design and production but also to interconnect other systems such as compartmentation, outfitting, piping, etc. Computer graphics is adopted of the visualization of model.

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.223-232
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• 2003

In this study, a constitutive model called the disturbed state concept (DSC) was modified to be applied to the interface shear stress-displacement relationship between geosynthetics. The DSC model is comprised of two reference states, namely the relative intact (RI) and the fully adjusted (FA) state, and one function, namely the disturbance function. This model is a unified approach and can allow for various models as an RI state such as elastic-perfectly plastic model, hierarchical model, and so on. In addition, by using this model, the elastic and plastic displacements can be considered simultaneously. Comparisons between the measured data and predicted results through the parameters determined from four sets of large direct shear tests showed good agreements with each other, especially for the smooth geomembrane-involved interface. Although there are slight differences at peak shear strength for textured geomembrane-involved interface, this model can still be useful to predict the position of displacement at peak strength and the large displacement (or residual) shear strength.

• Geotechnical Engineering
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• v.12 no.2
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• pp.95-106
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• 1996

In this study, a constitutive model which can describe the anisotropic and plastic behaviors of natural cohesive soils, was developed based on anisotropic bounding surface theory. The model was fomulated by the concepts of the improved anisotropic bounding surface function, nonassociated flow rule with new plastic potential function, anisotropic hardening rule, and new mapping rule governing the plastic behavior inside bounding sutraface. Comparing with the results of Ku consolidation and triaxial shearing tests, the predictions by the proposed model agree quite well with real soil responses.

• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.167-172
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• 2008

Recently a high-quality voxel model of a Korean adult male was constructed at Hanyang University by using very high resolution serially-sectioned anatomical images of a cadaver, which was provided by the Korean Institute of Science and Technology Information (KISTI). Most existing voxel phantoms are developed based on an individual in the supine posture. This study converted the HDRK-Man voxel model into surface model and adjusted the flattened back of the HDRK-Man to a normal shape in the upright posture using 3D graphic softwares such as $3D-DOCTOR^{TM}$, $Rapidform^{(R)}$2006, $Rhinoceros^{(R)}$4.0, $MAYA^{(R)}$8.5. The effective doses of adjusted model were compared with those of unadjusted model for some standard irradiation geometries (i.e., AP, PA, LLAT, RLAT). In general, the differences were not very large and, among those, the largest difference was found for the PA radiation geometry, as expected. These methodologies can be used for the development of various deformed posture models of HDRK-Man in the later stage of this project.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.198-201
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• 1999

고주파를 이용한 해저면 후방산란강도를 진해 해군사관학교 내의 실험해역에서 측정하였다. 측정된 후방산란강도를 수평입사각의 함수로 나타낸 후 Jackson 모델과 비교, 분석하였다. 해저면 구성성분을 파악하기 위해 다이버에 의해 코어링이 채취되었으며, 해저면 환경파라메터들은 Hamilton 모델에 의해 산출되었다. 분석 결과, 해저면이 거칠 경우 고주파 해저면 후방산란강도는 퇴적층 내부의 체적산란강도 보다 해저면 거칠기에 의한 산란의 영향을 많이 받는 것을 알 수 있었다.