• Journal of the Korean Society for Advanced Composite Structures
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• v.5 no.3
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• pp.17-22
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• 2014

Fiber reinforced plastic (FRP) structural shapes are readily available in civil engineering applications. Among many manufacturing techniques used for FRP structural shapes, pultrusion process is one of the most widely used techniques in civil engineering applications. Pultrusion is a manufacturing process for producing continuous lengths of reinforced polymeric plastic structural shapes with constant cross-section. Pultruded composites are attractive for structural applications because of their continuous mass production with excellent mechanical properties. This paper presents the results of investigations pertaining to the bolted connection with two bolts for the pultruded FRP (PFRP) structural members. PFRP bolted connection tests were conducted with end distance to bolt diameter ratio ($e_1/d_b$) and two types of bolt pattern such as horizontal (Pattern A) and vertical arrangement (Pattern B). As a result, it is found that the $e_1/d_b$ is recommended as the ratio of 4. In addition, it is also found that the bearing strengths at failure of the Pattern A and Pattern B have a similar value.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.5
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• pp.447-454
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• 2016

In the meantime, looking at the present status of how to estimationte the quantity of rebar based on 3D BIM getting the limelight in these days, commercial BIM tools provide rebar modeling functions however it takes a vast amount of modeling time for modeling of rebar in use of that function hence there is no BIM software at present for practical use. Therefore, in this study, we organized and presented a practical rebar quantity estimationtion process in BIM-based design work-site and intended to develop a program named Rebar Automatic Arrangement Program - hereinafter called RAAP - which enables automatic rebar arrangement based on much more precise cross-sectional information of bars in column, beam, slab and wall than the one from existing 2D method under the conditions without any cross-sectional information in the initial design phase. In addition, we intended to establish rebar quantity estimationtion process in the initial design phase through interworking of modeling & quantity estimationtion functions in consideration of joint, anchoring length of BuilderHUB as a BIM software with RAAP. The results from this study are practical in developing a technology that is able to estimationte quantity with more improved reliability than the one from existing 2D-based methods with less effort when the quantity of framework is estimationted in the uncompleted state of cross-sectional design for structural members in the initial design phase of a construction project. And it is expected that it could be utilized as a basic study from which a reasonable quantity estimationtion program can be established in the initial design phase.

• Fashion & Textile Research Journal
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• v.6 no.1
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• pp.17-22
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• 2004

The purpose of this study was to obtain the basic element of patterns, which is the motif, from the existing art works and use it to create and simulate a variety of patterns to show the practical use of the computer. Natural dyed works of geometric shapes like squares and 1/4 of circles, each dyed with a different natural dyes, were produced and motifs were extracted. Then using the 4D box in Adobe Photoshop v.6.0, the developing pattern change and simulation effects when using different patterns and different repetition settings were examined. Observations were made as the motifs were replicated. Different patterns like a diagonal line, a square and a circle appeared. In order to find out the effects according to the changes, the motifs from work's square portions, circle centre, and the composition of eight motifs were extracted and used. The repeated patterns according to the extracted motifs simply showed that in the case of just repeating and arranging, square patterns appeared. By replicating and arranging, the motif and the allophone were matched and patterns with regular lines were formed, like a twill, pointed twill line. By setting the direction to Y and X in the repetition methodes, a typical half-drop arrangement or a brick pattern arrangement were formed according to 1/4, 2/4, 3/4, 1/3, or 2/3 in changes. Also the steepness of the slope changes quickly or in turn slowly as the rhombus shape appears. However in the case of a composed motif, an ogee pattern appeared. Lastly, by 3-D mapping patterns like a slant line, pointed twill patterns, diamond patterns, and the repeat patterns of a motif with a circle and a line combined, and a circle motif, an optical illusion could be observed.

• Korean Journal of Construction Engineering and Management
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• v.5 no.4 s.20
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• pp.107-114
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• 2004

This paper represents the application of the 3D CAD Model data for 4D simulation and quantity estimation. These support the effective and practical use of 4D CAD model. By using and manipulating the 3D CAD model information, scheduling and quantity estimation could be developed more quickly and effectively. So the 3D CAD model information is made use of not only drawing a blueprint but also playing an important part of data integration platform. The scheduling module sets up the schedule generation logic that consists of period, priority of element arrangement, and time lag of floor placement. It sorts the working items as a priority of working process. And the quantity estimation module queries the material quantity of the structural elements according to the scheduling conditions. These two modules are developed using the 3D CAD model information and assist the function of 4D CAD model.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.3
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• pp.246-253
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• 2022

Flabby tissue is not rare for denture wearers. Mucostatic impression technique is necessary due to compromised retention and stability of denture resulting from distortion of mobile flabby tissue. In this report, individual tray was fabricated by model-scanning and 3D printing treatment denture. And then, mucostatic impression for flabby tissue was obtained by using individual tray modified with window technique. Definitive denture was fabricated based on information of treatment denture including incisal pontic arrangement, jaw relationship and occlusion.

• Journal of computational fluids engineering
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• v.4 no.1
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• pp.27-33
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• 1999

Spiral tube heat exchangers can find numerous applications in many engineering fields. Flow in spiral tubes is interest to engineers due to occurrence of secondary flow which enhances the cross-sectional mixing and the heat transfer rate. In the present study, an incompressible viscous 3-D flow in spiral tubes with rectangular cross-section of various torsion rate and Reynolds number is studied by using a finite volume method. It is shown that the axial velocity profile is affected by the secondary flow motion. Because there is some difference from correlation proposed by Hur et al., a lot of analysis and arrangement of experimental results are needed. This study showed the results of variation of hydrodynamic entry length for torsion and Re numbers.

• Journal of the Korean Society of Visualization
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• v.1 no.1
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• pp.92-97
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• 2003

A new Stereoscopic PTV was developed using two CCD cameras, stereoscopic photogrammetry based on a 3D-PTV principle. Virtual images were produced for the benchmark test of the constructed Stereoscopic PTV technique. The arrangement of the two cameras was based on angular position. The calibration of cameras and the pair-matching of the three-dimensional velocity vectors were based on the Genetic Algorithm based 3D-PTV technique. The constructed Stereoscopic PTV technique was tested on the standard images of the impinged jet proposed by VSJ. The results obtained by the constructed system showed good agreements with the original data.

• Coupled systems mechanics
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• v.1 no.1
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• pp.1-7
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• 2012

The problem of laterally loaded piles is particularly a complex soil-structure interaction problem. The flexural stresses developed due to the combined action of axial load and bending moment must be evaluated in a realistic and rational manner for safe and economical design of pile foundation. The paper reports the finite element analysis of pile groups. For this purpose simplified models along the lines similar to that suggested by Desai et al. (1981) are used for idealizing various elements of the foundation system. The pile is idealized one dimensional beam element, pile cap as two dimensional plate element and the soil as independent closely spaced linearly elastic springs. The analysis takes into consideration the effect of interaction between pile cap and soil underlying it. The pile group is considered to have been embedded in cohesive soil. The parametric study is carried out to examine the effect of pile spacing, pile diameter, number of piles and arrangement of pile on the responses of pile group. The responses considered include the displacement at top of pile group and bending moment in piles. The results obtained using the simplified approach of the F.E. analysis are further compared with the results of the complete 3-D F.E. analysis published earlier and fair agreement is observed in the either result.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2246-2252
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• 2009

A new metamaterial antenna with dual resonant modes is presented using an asymmetrical periodic arrangement for orthogonal radiation patterns. The proposed antenna produces two orthogonal modes by the asymmetrical periodic unit-cell arrangement. The orthogonal resonant mode provides perpendicular radiation patterns without changing the antenna polarization at each resonant mode. The fabricated antenna shows good agreements with the theoretical analysis of the electric-field. The experimental results shows the orthogonal radiation patterns along x- and y-axises, and gains are 3.34 and 3.86 dBi at each radiating resonant mode, respectively. Additionally, slotted ground structures are embedded on the back side of the antenna in order to reduce the size and enhance the radiation efficiency of 12 % and 27 %, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.5
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• pp.1113-1118
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• 2008

Strip layout design in progressive die is an important factor that determines the applicability of mass production. In this study, the layout design of bracket strips used fer automobiles was executed. The strip layout design was made in 3D with the use of Cimatron die design, an automation module rather than a 3D modeling module. Blank layout has been optimized through a layer arrangement of the wide run positioning inside carrier (double-row and two-pass type). The 3D CAD/CAM software used was Cimatron Die Design; the strip layout design was completed in ten processes.