• Journal of Fashion Business
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• v.23 no.6
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• pp.27-36
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• 2019

This study aimed to analyze the color differences by warp direction of textile mosaics by focusing on two representative textile wallcovering types, woven and string. Mosaics made of string can be expressed as having three-dimensionality based on color differences resulting from the warp direction of the string. String wallcoverings, unlike woven or non-woven wallcoverings, only have vertically oriented warp lamination on the backing paper without weft, and therefore, the reflection and backing color can be expressed differently depending on the angle of the mosaic. In this study, two identical wallcoverings were manufactured using the same materials but using different textile types, woven and string. The wallcoverings underwent die-cutting by each angle and were deployed in cube form. The analysis was based on ISO 5631-1:2015. The color difference between the two wallcoverings, woven and string, was shown as ΔE* 9.29. Based on the standard deviation of the color difference for each mosaic angle, woven ranged from ΔE* 0.09 to 0.94 and string ranged from ΔE* 1.92 to 3.74, showing a larger color difference. Thus, using the color differences of string to create a mosaic wallcovering improved dimensionality.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.3
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• pp.201-207
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• 2020

In this study, various types of porous beams were designed and analyzed to examine the relationship between the behavior of a porous beam and certain nonlocal parameters. The nonlocal parameters were defined as functions of the conditions of defects in the porous material. Finite element analysis was conducted on the beams under typical boundary and loading conditions. Beams with stiffeners having the same dimensions as the defects in the porous beams were also analyzed. The deformation tendency of these beams was determined and described in terms of the nonlocal parameters. The deformation of a porous beam was linearly proportional to the square of the diameters of the defects, whereas that of a beam with a stiffener was linearly proportional to the cube of the diameter of the stiffener. Furthermore, for a stiffened beam with axial loading, the results derived from a 3D solid element and those under 2D plane stress conditions were different.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.2
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• pp.132-140
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• 2001

This paper proposes an efficient walktlu-ough animation from two images of the same scene. To make animation easily and fast, Tour Into the Picture(TIP) enables walkthrough animation from single image but lacks the reality of its foreground object when the viewpoint moves from side to side, and view morphing uses only 2D transition between two images but restricts its camera path on the line between two views. By combining advantages of these two image-based techniques, this paper suggests a new virtual navigation technique which enable natural scene transformation when the viewpoint changes in the side-to-side direction as well as in the depth direction. In our method, view morphing is employed only in foreground objects , and background scene which is perceived carelessly is mapped into cube-like 3D model as in TIP, so as to save laborious 3D reconstruction costs and improve visual realism simultaneously. To do this, we newly define a camera transformation between two images from the relationship of the spidery mesh transformation and its corresponding 3D view change. The result animation shows that our method creates a realistic 3D virtual navigation using a simple interface.

• Journal of Biomedical Engineering Research
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• v.38 no.3
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• pp.116-122
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• 2017

Physical breast phantoms would be useful for the development of a dedicated breast computed tomography (BCT) system and its optimization. While the conventional breast phantoms are available in compressed forms, which are appropriate for the mammography and digital tomosynthesis, however, the BCT requires phantoms in uncompressed forms. Although simple cylindrical plastic phantoms can be used for the development of the BCT system, they will not replace the roles of uncompressed phantoms describing breast anatomies for a better study of the BCT. In this study, we have designed a numerical voxel breast phantom accounting for the random nature of breast anatomies and applied it to the 3D printer to fabricate the uncompressed anthropomorphic breast phantom. The numerical voxel phantom mainly consists of the external skin and internal anatomies, including the ductal networks, the glandular tissues, the Cooper's ligaments, and the adipose tissues. The voxel phantom is then converted into a surface data in the STL file format by using the marching cube algorithm. Using the STL file, we obtain the skin and the glandular tissue from the 3D printer, and then assemble them. The uncompressed breast phantom is completed by filling the remaining space with oil, which mimics the adipose tissues. Since the breast phantom developed in this study is completely software-generated, we can create readily anthropomorphic phantoms accounting for diverse human breast anatomies.

• The KIPS Transactions:PartA
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• v.10A no.1
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• pp.59-68
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• 2003

3-D data modeling of a volumetric scattered data is highly demanded for geological structure inspection, environment visualization and supersonic testing. The data used in these area are generally irregularly scattered in a volume data space, which are much different from the structured points data (cuberille data) used in Marching cube algorithm. In this paper, first we explore a volume modeling method for the scattered data based on tetrahedral domain. Next we propose a method for solving the ambiguity of tetrahedral domain decision using asymptotic decider criterion. Last we implement a simple visualization system based on the proposed asymptotic decider criterion and compare it with a system based on sphere criterion. In deciding tetrahedral domain, sphere criterion considers only positional values but asymptotic decider criterion considers not only positional values but also functional values, so asymptotic decider criterion is more accurate on deciding tetrahedral domain than sphere criterion.

• Geophysics and Geophysical Exploration
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• v.15 no.1
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• pp.33-38
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• 2012

A resistivity method has been applied to wide range of engineering and environmental problems with the help of automatic and precise data acquisition. Thus, more accurate modeling and inversion of time-lapse monitoring data are required since resistivity monitoring has been introduced to quantitatively find out subsurface changes With respect to time. Here, we used the finite element method (FEM) for 3D resistivity modeling since the method is easy to realize complex topography and arbitrary shaped anomalous bodies. In the FEM, the linear elements, also referred to as first order elements, have certain advantages of simple formulation and narrow bandwidth of system equation. However, the linear elements show the poor accuracy and slow convergence of the solution with respect to the number of elements or nodes. To achieve the higher accuracy of finite element solution, high order elements are generally used. In this study, we developed a 3D resistivity modeling program using high order Serendipity elements. Comparing the Serendipity element solutions for a cube model with the linear element solutions, we assured that the Serendipity element solutions are more accurate than the linear element solutions in the 3D resistivity modeling.

• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.1081-1089
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• 1999

Volume data modeling is concerned with finding a mathematical function which represents the relationship implied by the 3D data. Modeling a volume data geometrically can visualize a volume data using surface graphics without voxelization. It has many merits in that it is fast and requires little memory. We proposes, a method based on wavelet transformation and tetrahedrization. we implement a prototype system based on the proposed method. Last, we evaluated the proposed method comparing it with marching cube algorithm. the evaluation results show that though the proposed method uses only 13% of the volume data, the images generated is as good as the images generated by the marching cubes algorithm.

• Elastomers and Composites
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• v.34 no.3
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• pp.239-246
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• 1999

Side wall samples from a used automotive tire were subjected to subcritical and supercritical decomposition and extraction with three solvents, water, 28% ammonia solution and ammonia. For 6mm cube samples the rate of supercritical extraction with water followed a first-order kinetics with an activation energy of 140 kJ/mol. Solvent power of 28% ammonia so lotion at supercritical condition was found to be higher than supercritical water at initial extraction as pressure decreased. These phenomena were considered to be an effect of ammonia involved in water.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1885-1890
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• 2008

3-D heterogeneous nucleation was simulated by classical molecular dynamics (MD), where the Lennard-Jones (LJ) gas and solid cluster-seed molecules have argon and aluminum properties, respectively. There are three shapes of cluster-seeds, cube, rod, and sphere, and three classes of masses and the simulation took place under nine supersaturation ratios, making a total of 81 calculations. Results show that the dimension of the cluster-seed highly affects the rates of cluster development. In order to analyze heterogeneous nucleation above and below the critical supersaturation ratio, growth rate and liquefaction rate were separately defined to supplement the investigation. Design of experiments (DOE) was used for analysis which displayed that the shape and mass of the cluster-seed are prominent for the growth rate, while the supersaturation ratio is most significant followed by the mass for liquefaction rate. The significance of the supersaturation ratio for overall liquefaction suggests that thermal diffusion is more dominant than mass interactions for this system.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.587-589
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• 1997

The virtual surgical trial of TAH is very important in some points as follows. The chests of patients who is under heart-disease are various types of undefine form. It is hard to say that there exist the standard shape of TAH and the position to surgern. So, the virtual surgery system is very important in realizing TAH surgery of human. We have implemented virtual surgery system of TAH that supporting multi volume fitting trial. We have acquired CT images of patients with DICOM format. Each organ of patients was segmented in 2-dimensional CT images. 3-dimensional objects were made with marching cube algorithm and save as file in VRML format. Virtual fitting trial was performed on Cosmo-World; a VRML editor. The collision points of TAH with other organs were well observed. And the best position and angles were determined and saved or each case. We believed that this virtual surgery will be helpful in TAH surgery and TAH customizing.