• Composites Research
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• v.28 no.4
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• pp.176-181
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• 2015

In this study, the Z-shape fabric design is proposed as the way to enhance the ballistic performance of fabrics which are used as the intermediate layer of stuffed Whipple shield configurations. The Z-shape fabric employs a different boundary condition from those of conventional configurations of fabrics which include 4 edge fixed. Impact analysis on Z-shape aramid yarns and fabrics using LS-DYNA software was performed and the results were compared with 2 edge fixed and 4 edge fixed fabrics to identify the high velocity impact energy absorption characteristics of the Z-shape fabric. It was revealed that the Z-shape showed different impact behavior and higher energy absorption performance than 2 and 4 edge fixed fabrics.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.279-286
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• 2000

The objective of this research is to detect the papaya fruits on tree in an orchard. The detection of papaya on natural background is difficult because colors of fruits and background such as leaves are similarly green. We cannot separate it from leaves by color information. Therefore, this research will use shape information instead. First, we detect an interested object by detecting its boundary using edge detection technique. However, the edge detection will detect every objects boundary in the image. Therefore, shape description technique will be used to describe which one is the interested object boundary. The good shape description should be invariant in scaling, rotating, and translating. The successful concept is to use Fourier series, which is called "Fourier Descriptors". Elliptic Fourier Descriptors can completely represent any shape, which is selected to describe the shape of papaya. From the edge detection image, it takes a long time to match every boundary directly. The pre-processing task will reduce non-papaya edge to speed up matching time. The deformable template is used to optimize the matching. Then, clustering the similar shapes by the distance between each centroid, papaya can be completely detected from the background.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.2
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• pp.102-107
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• 2017

This study focuses on the effect of the elasticity modulus of jig material on blade edge shape in the grinding process of a sapphire medical knife. The ELID grinding process was applied as the edge-grinding method for sapphire material. Carbon steel and copper have been selected as the hard and soft jig materials, respectively. The blade edge created by ELID grinding was measured by a surface roughness tester and optical microscope. The shape of the ground edge and surface roughness were compared using the measurement results. As a result, it was found that chipping in the blade edge of the sapphire knife occurred more than in the case of jig material with a high-elasticity modulus because of the high normal force in the grinding process. Moreover, the maximum height surface roughness, $R_{max}$,of the ground surface was higher in the case of the jig material with a high-elasticity modulus due to the difference in elasticelongation. It was considered to lead to chipping from the notch effect.

• Journal of computational fluids engineering
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• v.19 no.4
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• pp.75-79
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• 2014

In the paper, a study on the analysis of the effects of trailing edge thickness on the aerodynamic characteristics of an airfoil is described. In this research, modification of the formula representing NACA symmetric airfoil is studied to change the airfoil shape with different trailing edge thickness of user's choice. According to the result of aerodynamic characteristics, as the trailing edge thickness increases the maximum lift coefficient increases while the lift-to-drag ratio decreases. In this paper flow calculation results are demonstrated and the analysis on those results and findings on the effects of non-zero thickness of trailing edge are suggested.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.233-236
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• 2003

In this paper, we propose a method to search the evidence such as a knife found in the crime scene based on GHT from an image database Such objects like knives are simitar in shape. The proposed method utilizes the small shape differences among objects as much as possible to distinguish an object from similar shaped objects. It consists of the GHT based candidate generation and top-down candidate verification. For the fast generation of the candidate 1ist, the GHT operation is performed un the down sampled edge list. The test results show that it can retrieve the correct object even with a pan of object in reasonable time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.711-714
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• 2015

A new technique for image restoration using Weighted cross-shaped median filter with edge-detection algorithm is proposed in this paper. It consists of simple hypothesis test for edge-detection, and makes use of the weighted cross-shape window. This method is applied to noise corrupted image and its results are compared with those of median filters. As for the experimental result, method of weighted cross-shape median filter is superior to other median filters.

• Journal of Digital Contents Society
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• v.10 no.2
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• pp.319-326
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• 2009

In this paper, we present an algorithm which recognize hand shape in real time using only image without adhering separate sensor. Hand recognizes using edge orientation histogram, which comes under a constant quantity of 2D appearances because hand shape is intricate. This method suit hand pose recognition in real time because it extracts hand space accurately, has little computation quantity, and is less sensitive to lighting change using color information in complicated background. Method which reduces recognition error using principal component analysis(PCA) method to can recognize through hand shape presentation direction change is explained. A case that hand shape changes by turning 3D also by using this method is possible to recognize. Human interface system manufacture technique, which controls a home electric appliance or game using, suggested method at experience could be applied.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.6
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• pp.615-626
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• 2010

The discrete-layer model is proposed to analyze the edge-effect problem of laminates under extension and flexure. Based on three-dimensional elasticity theory, the displacement fields of each layer in a laminate have been treated discretely in terms of three displacement components across the thickness. The displacement fields at bottom and top surfaces within a layer are approximated by two-dimensional shape functions. Then two surfaces are connected by one-dimensional high order shape functions. Thus the p-convergent refinement on approximated one- and two-dimensional shape functions can be implemented independently of each other. The quality of present model is mostly determined by polynomial degrees of shape functions for given displacement fields. For nodal modes with physical meaning, the linear Lagrangian polynomials are considered. Additional modes without physical meaning, which are created by increasing nodeless degrees of shape functions, are derived from integrals of Legendre polynomials which have an orthogonality property. Also, it is assumed that mapping functions are linear in the light of shape of laminated plates. The results obtained by this proposed model are compared with those available in literatures. Especially, three-dimensional out-of-plane stresses in the interior and near the free edges are evaluated and convergence performance of the present model is established with the stress results.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.2
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• pp.131-139
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• 2003

Shape descriptors play an important role in systems for object recognition, retrieval, registration, and analysis. Seven well-known descriptors including MPEG-7 visual descriptors arebriefly reviewed and a new robust pattern recognition descriptor is proposed. Performance comparison among descriptors are presented. Experiments show that the newly proposed descriptor yields better performance results than Fourier, invariant moment, and edge histogram descriptors.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.12 no.4
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• pp.405-413
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• 1987

In this paper, we have discussed three-type median filters(SQUARE, CROSS, X-SHAPE) that preserving edge in an original image while reducing random noise was introduced for image enhancement and edge detection on radar image. Since radar image have a number of parts of curve, we compared results produced by edge detection operater proposed for improving the parts of curve with results of using the existing edge detection methods, such as Roberts, Sobel, Prewitt, Laplacian and Kirsch.