• Steel and Composite Structures
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• v.2 no.2
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• pp.99-112
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• 2002

The differential quadrature method (DQM) is a numerical technique of rather recent origin, which by its continually increasing applications in different problems of engineering, is a competing alternative to the conventional numerical techniques for the solution of initial and boundary value problems. The work of this paper concerns the application of the DQM in the area of the buckling of multi layered orthotropic composite plates with various boundary conditions the buckling of multi layered composite plates with constant and variable thickness under axial compressive static loading is considered. The effects of fiber orientation and boundary conditions on static behavior of composite plates are presented. The comparison of results from the present method and those obtained from NISA II software shows the accuracy and reliability of this method.

• KCI Concrete Journal
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• v.11 no.3
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• pp.115-126
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• 1999

An analytical method based on the nonlinear layered finite element method is developed to simulate an overall load-deflection behavior of strengthened beams. The developed model distinguishes itself by its capability to trace residual flexural behavior of a beam after the fracture of brittle strengthening materials at peak load. The model. which uses a rather advanced numerical technique for iterative convergence to equilibrium, can be regarded as superior to the two models based on load control and displacement control The model predictions were compared with the experimental results and it was observed that there was good agreement between them.

• Magazine of the Korea Concrete Institute
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• v.3 no.3
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• pp.121-128
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• 1991

Thicknesses of the hase concrete blocks supportmg large machmes were estimated by analyzing the res- 0 ¬nance modes of mechanical Vibrations The vibration was produced by the mechanical impact with steel ball drop and detected by a wideband comcal piezoelectric transducei. The detected signals were analyzed by FFT and thicknesses of specimen were determined by the resonant frequency of vibratIon. For the layered concrete block, the estimated thickness is dependent on the acoustic reflective index at the boundary between layers. The estimated thickness up to 100em were in goo:l agreement with the real value. In additlOn. this technique could be applicable to the estimation of the bondmg status of the layered structures.

• Journal of Korea Game Society
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• v.13 no.2
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• pp.99-110
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• 2013

As volume rendering has been applied for computer game, the visualization of volume data with surface data in one scene has been required. Though a hybrid rendering of volume and surface data have been developed using the GPGPU functionality, computer games which run on low-level hardware are difficult to perform the hybrid rendering. In this paper, we propose a new hybrid rendering based on DirectX 9.0 and general hardware. We generate the layered depth images from surface data using a new method to reduce the depth complexity and generation time. Then, we perform the hybrid rendering using the layered depth images. In the rendering process, we suggest a new method to transform the coordinate system from a surface coordinate to a volume coorinate and propose an accelerated rendering technique. As the result, we can perform volume-surface hybrid rendering in an efficient way.

• KCI Concrete Journal
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• v.13 no.2
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• pp.10-18
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• 2001

The spectral analysis of surface waves (SASW) method, which is an in-situ seismic technique, has mainly been developed and used for many years to determine the stiffness profile of layered media (such as asphalt concrete and layered soils) in an infinite half-space. This paper presents a modified experimental technique for nondestructive evaluation of in-place cement mortar compressive strength in single-layer concrete slabs of rather a finite thickness through a correlation to surface wave velocity. This correlation can be used in the quality control of early age cement mortar structures and in evaluating the integrity of structural members where the infinite half space condition is not met. In the proposed SASW field test, the surface of the structural members is subjected to an impact, using a 12 mm steel ball, to generate surface wave energy at various frequencies. Two accelerometer receivers detect the energy transmitted through the medium. By digitizing the analog receiver outputs, and recording the signals for spectral analysis, surface wave velocities can be identified. Modifications to the SASW method includes the reduction of boundary reflections as adopted on the surface waves before the point where the reflected compression waves reach the receivers. In this study, the correlation between the surface wave velocity and the compressive strength of cement mortar is developed using one 36"x36"x4"(91.44$\times$91.44$\times$91.44 cm) cement mortar slab of 2,000 psi (140 kgf/$\textrm{cm}^2$) and two 36"x36"x4"(91.44$\times$91.44$\times$91.44 cm) cement mortar slabs of 3,000 psi (210 kgf/$\textrm{cm}^2$).

• Journal of Korea Multimedia Society
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• v.9 no.10
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• pp.1282-1295
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• 2006

This paper proposes a method of image tile mosaics to preserve detailed depiction of the source image. This method enhance the shortcoming of the previous mosaic methods that cannot express the detailed depiction because of the gap between tiles. Our method is implemented by the usage of image tiles to preserve detailed depiction of the source image, as well as the usage of 2-layered tiles to.eliminate the gap between tiles. The method suggested in this paper are composed of following process. First of all, the position of the upper layer tile is located through a centroidal voronoi diagram to which an edge avoidance technique is applied, and the position of the lower layer tile is calculated using Delaunay triangulation. Secondly, discover the size and direction field of the tile considering the relation between tiles. Thirdly, adopt a photomosaic technique to use the image tiles. At this time, the technique of multi-level indexing is used to accelerate the speed of image searching. Through above process, the gap between tiles is minimized against other methods and a mosaic image with a maximized detailed description is achieved.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.2
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• pp.45-57
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• 2022

This study aims to analyze the macramé technique used in costume design based on the cases from 2011 to 2020, when the macramé technique became popular. The research data are the results of analyzing the materials, clothing items, and structural combination of macramé knots by season, year, and collection from 2011 S/S to 2020 F/W, focusing on the four major fashion collections New York, Paris, London, and Milan. Macramé appeared often in the S/S season, and in the 2019 and 2020 S/S seasons, macramé was identified as a keyword for fashion trends based on its frequent usage. Overhand knots were used the most for the types of macramé knots used in costumes, and overhand knots were also used the most in the S/S season and in the New York, Paris, and Milan collections. Rope was the most frequently used material for macramé knots, and it was confirmed that it appeared frequently in 2011 and 2019, and ropes were also used often in the London, Milan, and Paris collections. One-piece appeared the most in the S/S season and F/W season as costume items. In addition, the costumes used as layers in the S/S season appeared most often, and in 2019 and 2020, the layered combination appeared most frequently in London and New York collections. It is judged that macramé appears repeatedly in the S/S season depending on the type of knot and is used as a layered look, making it a decorative element rather than a practical element. This study is expected to help develop modern fashion design by drawing attention to the value of the macramé technique expressed as handcrafted work.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.2
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• pp.139-147
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• 2008

This study aims to investigate and analyze sewing methods according to the shape of the inner collar among women's jeogories in order to understand such sewing techniques, which has emerged during modern Korea, and has utilized diversly for the shape of the jeogori's inner collar and as part of the inner collar. The study was conducted on relics possessed between 1900 to 1990, or 515 pieces of jeogories. Jeogories were classified into single-layered and double-layered jeogories according to the shape of their composition. Inner collar shapes of jeogories have also been categorized. It was found that single-layered jeogories comprise 49 inner collars with shapes identical to those of the outer collars. Double-layered jeogories comprise of the following three types: 43 pieces of godae close, 18 pieces in which the inner collar of the outer bodice are cut without a connecting line and the inner collar of the godae and inner bodice are suspended, and 405 pieces in which the share of the inner collar is identical to that of the outer collar. From the shapes of inner collars mentioned above, the following sewing methods have been derived: 1. To sew the inner collar of single-layered jeogories, a seaming technique had been used. 2. Among the inner collars of a double-layered jeogori, godae close was sewn with only a short part of the godae by using a lining, and then finished with overage and blind stitches. Godae close was a covenient way to attach inner collars, and also saved much time. 3. Inner collars with shapes identical to the outer collar are divided into two groups: those with outer collars cut out fellowing the cloth without seam and shifted towards the linings and used as an inner collar, and those with outer collars made of outer linings and inner collar of inner linings. To sew the collar, paste and needlework had been employed, where the methods of needlework were divided into blind stitch, overage stitch, and catch stitch. In sewing with paste, only godae was blind stitched or overage stitched, and the remainder had been painted with paste or the collar had been finished with heated soldering iron after the entire inner collar was painted with paste.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.84-89
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• 2001

Ultrasonic pulse echo method comes to be difficult to apply to the multi-layered structure with very thin layer, because the echoes from the top and the bottom of the layer are overlapped. Conventionally method, deconvolution technique has been used for the decomposition of overlapped UT signals, however it has disabilities when the waveform of the transmitted signal is distorted according to the propagation. In this paper, the wavelet transform based deconvolution (WTBD) technique is proposed as a new signal processing method that can decompose the overlapped echo signals in A-Scan signal with superior performances compared to the conventional deconvolution technique. Performances of the proposed method are shown by through computer simulations using model signal with noise and are demonstrated by through experiments for the fabricated acryl rod with a thin steel plate bonded to it.

• Journal of Electrical Engineering and Technology
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• v.6 no.3
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• pp.408-413
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• 2011

In this paper, a real-coefficient approach to Adaptive Frequency Sampling (AFS) technique is developed for efficient equivalent circuit modeling of RF components. This proposed method is advantageous than the vector fitting technique and the conventional AFS method in terms of fewer samples leading to a lower order of a rational function on a given data and to a direct conversion to an equivalent circuit for PSPICE(Personal Simulation Program with Integrated Circuit Emphsis) simulation, respectively. To validate the proposed method, the distributed equivalent circuit of a presented multi-layered RF low-pass filter is obtained using the proposed real-coefficient AFS, and then comparisons with EM simulation and circuit simulation for the device under consideration are achieved.