• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_2
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• pp.643-651
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• 2012

Object recognition belongs to high-level processing that is one of the difficult and challenging tasks in computer vision. Digital photogrammetry based on the computer vision paradigm has begun to emerge in the middle of 1980s. However, the ultimate goal of digital photogrammetry - intelligent and autonomous processing of surface reconstruction - is not achieved yet. Object recognition requires a robust shape description about objects. However, most of the shape descriptors aim to apply 2D space for image data. Therefore, such descriptors have to be extended to deal with 3D data such as LiDAR(Light Detection and Ranging) data obtained from ALS(Airborne Laser Scanner) system. This paper introduces extension of chain code to 3D object space with hierarchical approach for segmenting point cloud data. The experiment demonstrates effectiveness and robustness of the proposed method for shape description and point cloud data segmentation. Geometric characteristics of various roof types are well described that will be eventually base for the object modeling. Segmentation accuracy of the simulated data was evaluated by measuring coordinates of the corners on the segmented patch boundaries. The overall RMSE(Root Mean Square Error) is equivalent to the average distance between points, i.e., GSD(Ground Sampling Distance).

• Journal of mucopolysaccharidosis and rare diseases
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• v.1 no.1
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• pp.5-14
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• 2015

This paper addresses the state of arts of microneedles for the transdermal drug delivery applications. Microneedles can be classified based on materials and shapes. For the materials, microneedles could be made of ceramics, metals and polymers. The shape of the microneedles can be classified into solid and hollow microneedles. Methods of transdermal drug delivery based on microneedle patch are discussed, and various fabrication methods of microneedle patches are introduced.

• Structural Engineering and Mechanics
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• v.5 no.2
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• pp.127-135
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• 1997

Patch recovery attempts to derive a more accurate stress filed over a particular element than the finite element shape function used for that particular element. Elements that have a free edge being the boundary to the structure have particular stress relationship that can be incorporated to the stress field to improve the accuracy of the approximation.

• Journal of Ocean Engineering and Technology
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• v.11 no.2
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• pp.138-144
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• 1997

This is describes the automatic mesh generation on the ship hull surface. At first ship hull is defined as a cillocation of composite surface patches which satisfy the geometic continuity between adjoining patches by using Gregory surface method. Node points that would be mesh points are ganerated by considering the surface curvature. The triangulation of the node points is by the combination of Ohtsubo's method and Choi's one. After triangulation, shape improvement and quadrilateralization is done with specific criterin. An application to the actual ship and the results are shown.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.7
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• pp.857-862
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• 2007

A novel compact ultra wideband(UWB) antenna for UWB application is proposed in this paper. The proposed antenna with $22mm{\times}26mm{\times}1.6mm$ covers the entire UWB bandwidth and has band notch characteristic for the frequency band of $5.15{\sim}5.825GHz$ limited by WLAN. The antenna has a concaved ground plane and staircase shape patch to achieve the wide bandwidth, and has an U shape slot with $\lambda/4$ length to notch the band. The return loss and group delay of the proposed antenna are measured.

• Journal of applied mathematics & informatics
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• v.27 no.5_6
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• pp.1017-1031
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• 2009

The problem of interaction of surface water waves by small undulation at the bottom of a laterally unbounded sea is treated on the basis of linear water wave theory for both normal and oblique incidences. Perturbation analysis is employed to obtain the first order corrections to the reflection and transmission coefficients in terms of integrals involving the shape function c(x) representing the bottom undulation. Fourier transform method and residue theorem are applied to obtain these coefficients. As an example, a patch of sinusoidal ripples is considered in both the cases as the shape function. The principal conclusion is that the reflection coefficient is oscillatory in the ratio of twice the surface wave number to the wave number of the ripples. In particular, there is a Bragg resonance between the surface waves and the ripples, which is associated with high reflection of incident wave energy. The theoretical observations are validated computationally.

• Korean Journal of Computational Design and Engineering
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• v.12 no.5
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• pp.330-343
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• 2007

In this paper, we present a new surface content completion system that can effectively repair both shape and appearance from scanned, incomplete point set inputs. First, geometric holes can be robustly identified from noisy and defective data sets without the need for any normal or orientation information. The geometry and texture information of the holes can then be determined either automatically from the models' context, or manually from users' selection. After identifying the patch that most resembles each hole region, the geometry and texture information can be completed by warping the candidate region and gluing it onto the hole area. The displacement vector field for the exact alignment process is computed by solving a Poisson equation with boundary conditions. Out experiments show that the unified framework, founded upon the techniques of deformable models and PDE modeling, can provide a robust and elegant solution for content completion of defective, complex point surfaces.

• Journal of the Korean Society of Costume
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• v.63 no.1
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• pp.135-146
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• 2013

The purpose of this study is to investigate the meaning and possible shape of Goryeo-Achungunsura-jisun(高麗鴉靑雲袖羅質孫) through the details regarding its color, fabric, and pattern in the $13-14^{th}$ century writings and costume relics. Goryeo-Achungunsura-jisun was the summer dress coat that government officials wore during the Jisun feast of Yuan, and it was symbolic of the political strategy of Yuan as well as the excellent Goryeo fabric material, but no relics remain. During this period, Achung (dark blue)was the color that was used to dye silk, dress coats of upper class men, and background fabric of the embroidered official patch. And, the term, Yunsu (cloud sleeves), was probably sleeves with cloud pattern. The most typical cloud pattern in the 13 and the $14^{th}$ century was the 'flowing, gathering-headed cloud'. The Ra(silk gauze) weaving technique of Goryeo was developed rapidly in the $12^{th}$ century, and the quality of the Ra in the late Goryeo was good enough to be used for making the official's dress coat in the golden age of Yuan. According to the characteristic of jisun and man's formal-suit style in the Mongolian-Yuan, the possible styles for Goryeo-Achungunsura-jisun can be summarized as follows: a basic Mongolian gown with narrow sleeves and deep crossed diagonal opening, a Mongolian gown with waist pleats, the combination of half sleeved gown and long sleeved Mongolian gown. These styles would be made of delicate Goryeo Ra, cloud patterned sleeves, fabrics dyed in dark blue color, and shawl or embroidered patch ornaments for officials of Yuan, which was more simple than materials for Khan's Jisun to avoid rebellions.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.2
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• pp.113-121
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• 2005

In order to resolve a common numerical integration inaccuracy of meshfree methods, we introduce an improved natural clement method called Petrov-Galerkin natural element method(PG-NEM). While Laplace basis function is being taken for the trial shape function, the test shape function in the present method is differently defined such that its support becomes a union of Delaunay triangles. This approach eliminates the inconsistency of tile support of integrand function with the regular integration domain, and which preserves both simplicity and accuracy in the numerical integration. In this paper, the validity of the PG-NEM is verified through the representative benchmark problems in 2-d linear elasticity. For the comparison, we also analyze the problems using the conventional Bubnov-Galerkin natural element method(BG-NEM) and constant strain finite clement method(CS-FEM). From the patch test and assessment on convergence rate, we can confirm the superiority of the proposed meshfree method.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.5
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• pp.491-503
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• 2014

In this paper, a $TM_{31}$ higher order mode half circular-ring microstrip antenna with monopole-like radiation characteristic for on-body communication is proposed. By using shorting vias, $TM_{31}$ resonance mode was excited, while achieving compact low-profile antenna with monopole-like radiation characteristics. To overcome the narrow bandwidth of a patch antenna, a C-shape half ring patch with shorting vias having $TM_{31}$ mode is closely located around a half circular patch. For size reduction, half mode is adopted. The proposed antenna has the overall dimensions of $0.25{\lambda}_0{\times}0.46{\lambda}_0{\times}0.025{\lambda}_0$ at the industrial, scientific, and medical(ISM) 2.45 GHz band(2.4~2.485 GHz) and the 10-dB return loss is 4.24 % ranging from 2.38 to 2.49 GHz. To verify body effect, two-thirds muscle equivalent semi solid phantom was fabricated and used to measure the antenna performance. A communication link is analysed to investigate the effect of human-body movements and antenna locations.