• Composites Research
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• v.30 no.6
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• pp.331-337
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• 2017

The composite lattice structures have advantages of high specific stiffness and strength and are mainly applied to the structures of launch vehicles that carry the compressive load. However, since these structures are manufactured by filament winding technology, there are some defects and voids found in the knots. For these reasons, the stiffness and strength of the lattice structures have to be compared with finite element model for predicting design load. But, the full scale test is difficult because time and space are limited and the shape of structure is complex, and hence the simple and reliable test methods for examination of stiffness are needed. In this paper, subelements of composite lattice structures were prepared and compressive and bending test were conducted for examination of stiffness of helical and hoop rib. Test methods for subelements of composite lattice structures that has curved and twisted shape were supposed and compared with finite element analysis results.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.835-837
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• 2017

In this paper, manufacturing processes of cylindrical composite lattice structures using filament winding method was described. Cylindrical composite lattice structures were manufactured in accordance with four major steps. Silicon mold of lattice shape was installed on mandrel and then continuous fiber was wound on silicon mold. After winding process, in order to ensure the same thickness for all regions, compression process was done for its intersection parts. Finally, the composite lattice structure was demoulded after curing in oven. It was found that the manufactured cylindrical composites lattice structure had 2.4% of dimensional error compared to the design requirements.

• Journal of architectural history
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• v.10 no.1 s.25
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• pp.9-23
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• 2001

This study is for the Kyungduk-Dan(as a altar of Milsung-Daegun) and The Manun-Jae the characteristics(lay out and planning, window patterns, structure, materials) of the the Korean traditional house during the modern era. Before Manun-Jae was used for the house. The Kyungduck-Dan was constructed in August according to the Lunar Calender in 1927. The Manun-Jae(house for Ki-hun Kang, millionaire ) was completed in 1924. Modern Architectures brought to Korea with the bricks, the tiles, the flash doors, the plate grasses, the brass hardwares. These architectural material was used in positive. During the construction of Manun-Jae in 1924, it happened the architectural exchage among a korean, a chinese and a japanese constructor. Though using the air exhaust valve at the kitchen of Ukyung-Kak( old Anchae), it could be assume that the modern convenience and the improvement of residential environments was considered at that period during the construction of Manun-Jae. That construction was elected with the brick($222mm{\times}106mm{\times}50mm$), the chinese colored tile and plate glass such a modem materials. The new shape of the korean lattice window and the wooden flash-door with glass was used. In Ukyung-Kak, the Chan-Maru(service space) and the kitchen such as a service space or concise utility zone was organically connected. Especially, considered the domesitic activity and circulation, the western kitchen sink and the Chan-Maru(service space) was rationally placed. At the Manun-Jae and the Kyungduck-Dan, the architectural characteristic is that the new shape of windows was used. The lattice window at the Ondol room of Ukyung-Kak, was rgadually added the plate glass and the wood plate. The lattice window with the grid shape at kitchen of that building was adapted japanese grid lattice window in korea at that period. It is the sample that korean traditional house was typically influenced from the japanese resident culture. The Manun-Jae and the Kyungduck-Dan as the modern house kept the form of korean traditional architecture, and was partially adapted a modern characteristic space and modern architectural materials. During the japanese occupancy, these residence can be showed the transition in formally.

• Geotechnical Engineering
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• v.13 no.2
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• pp.155-168
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• 1997

Lattice girder is a new steel support developed in Europe for the replacement of an existing H-shaped steel set, which is installed after tunnel excavation. Lattice girder has the following several advantages : 1. Lattice girder minimizes the amount of shotcrete shadow which happens to occur behind a steel support. 2. A triangular shape of lattice girder makes shotcrete placed efficiently. 3. Lattice girder provides a good bond strength for shotcrete, which makes the composite structure of lattice girder and shotcrete behave monolithic, and therefore, the rock load can be supported effectively by the lattice girder system, This paper presents the results from a model wall test, a strength test for shotcrete shot on the model wall and a strength test for the bond between lattice girder and shotcrete. These tests proved that lattice-girder system is superior to H-shaped steel-set system concerning the shotcrete rebound rate, the developed shotcrete strength and the adhesion characteristics.

• Computational Structural Engineering
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• v.26 no.1
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• pp.24-31
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• 2013

• Journal of the Korea Furniture Society
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• v.24 no.4
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• pp.400-407
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• 2013

21C modern society is a time when enough design to dominate the world, a unique design is required new in all aspects. In addition, there is a religion to the best of Zen art. In our cultural heritage with a ethnicity unique unparalleled in the world, and a new recognition of traditional culture and identity of its own in our country, lattice door flower temple the beauty of Korea in the way you tell, it was modernized by interpreting a new one to utilize as a design element of a wood lattice door flower temple. In this study, to re-appear in openwork having regard to the symbolism of pattern and shape of the lattice door flower temple molding properties were highlighted, change the part of the motif, repeated the curve geometric has been designed to simplify as. As a result, it is possible to present the possibility of a design element that can design a traditional Korean is reinterpreted Modern thereby simplify the repetitive element of the related art, for a new aesthetic changes unique. Design Development of wood with a Buddhist temple flower lattice modern re-interpretation, it suits while a strong indication Korea imagery and expressed a variety of needs and personality to the design elements that are competitive in the world the cage, and design of wood, various studies competitive on to be applied to each field is required.

• Structural Engineering and Mechanics
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• v.77 no.3
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• pp.417-439
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• 2021

The geometric nonlinearity has been successfully integrated with the design of steel structural system. Thus, the tubular lattice girder, one application of steel structural systems have already been optimized to obtain an economic design following the completion of computationally expensive design procedure. In order to decrease its computing cost, this study proposes to employ five multi-objective metaheuristics for the design optimization of geometrically nonlinear tubular lattice girder. Then, the employed multi-objective optimization algorithms (MOAs), NSGAII, PESAII, SPEAII, AbYSS and MoCell are evaluated considering their computing performances. For an unbiased evaluation of their computing performance, a tubular lattice girder with varying size-shape-topology and a benchmark truss design with 17 members are not only optimized considering the geometrically nonlinear behavior, but three benchmark mathematical functions along with the four benchmark linear design problems are also included for the comparison purpose. The proposed experimental study is carried out by use of an intelligent optimization tool named JMetal v5.10. According to the quantitative results of employed quality indicators with respect to a statistical analysis test, MoCell is resulted with an achievement of showing better computing performance compared to other four MOAs. Consequently, MoCell is suggested as an optimization tool for the design of geometrically nonlinear tubular lattice girder than the other employed MOAs.

• Journal of computational fluids engineering
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• v.19 no.2
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• pp.79-85
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• 2014

An air-water free surface flow simulation by using the Lattice Boltzmann Method(LBM) has not been studied a lot compared with the done by the Navier-Stoke equation. This paper shows the LBM is as one of the application tools for the free surface movement over an obstacle. The Mezo scaled application tool has been developed with two dimensional and nine discretized velocity direction using conventional lattice Bhatnagar-Gross-Krook model. Boundary conditions of a halfway-based for solid wall and a kinematic-based for interface are adopted. A validation case with a trapezoidal shape bump to make a comparison between freesurface movements from computational results and experimental ones was described with grid size dependency.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.6
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• pp.1126-1130
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• 2010

Speech production can be viewed as a filtering operation in which a sound source excites a vocal tract filter. The vocal tract is modeled as a chain of cylinders of varying cross-sectional area in linear prediction acoustic tube modeling. In this modeling the most common implementation assumes equal length of tube sections. Therefore, to model complex vocal tract shapes, a large number of tube sections are needed. This paper proposes a new vocal tract model with unfixed sectionlengths, which uses the reduced lattice filter for modeling the vocal tract. This model transforms the lattice filter to reduced structure and the Burg algorithm to modified version. When the conventional and the proposed models are implemented with the same order of linear prediction analysis, the proposed model can produce more accurate results than the conventional one. To implement a system within similar accuracy level, it may be possible to reduce the stages of the lattice filter structure. The proposed model produces the more similar vocal tract shape than the conventional one.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_1
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• pp.529-536
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• 2023

In this study, the spur gear with honeycomb lattice structures are designed. The pitch diameter and body length of the spur gear are Ø93 mm and 104.0 mm, respectively. The designed gear was printed using Powder bed fusion (PBF) 3D printer. The gear is 3D printed perfectly. Even the teeth and honeycombs of the gear were output in the same way as the design shape. The printed gear with honeycomb lattice structure has a 24% smaller cross-sectional area and 29% smaller volume and weight than conventional solid structure gears. The surface roughness is approximately 4.5㎛, and the hardness is 345 HV.