• Journal of Biosystems Engineering
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• v.28 no.2
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• pp.127-136
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• 2003

The top-to-bottom compression strength of corrugated board box is the most important mode of loading during it's no, and it depends largely on the edgewise compression strength of the corrugated board in the cross-machine direction and to a considerable extent on the flexural stiffness in both principal directions (CD; cross-machine direction, MD; machine direction) of the corrugated board. Corrugated board is a sandwich structure with an orthotropic property. The purpose of this study was to elucidate the principal design parameters for board combination of corrugated board from the viewpoint of bending strength through the finite element analysis [FEA] fur the various corrugated board. In general, the flexural stiffness [FS] in the MD was 2-3 times larger than that in the CD, and the effect of liner for the FS of corrugated board was much bigger than that of corrugating medium. The flexural stiffness index [FSI] was high when the stiffness of liner was in the order of inner, outer, and middle liner in double-wall corrugated board [DW], and the effect of the stiffness arrangement or itself reinforcement of corrugating medium on the FSI was not high. In single-wall corrugated board [SW] with DW. the variation of FSI with itself stiffness reinforcement of liner was much bigger than that with stiffness arrangement of liner. The highest FSI was at the ratio of about 2:1:2 for basis weight distribution of outer, middle, and inner liner if the stiffness of liner and total basis weight of corrugated board were equal in DW Secondarily. basis weight was in the order of inner, outer, and middle liner. However, the variation of FSI with basis weight distribution between liner and corrugating medium was much bigger than that with itself basis weight distribution ratio of liner and corrugating medium respectively in both DW and SW. md the FSI was high as more total basis weight was divided into liner. These phenomena fur board combination of corrugated board based on the FEA were well verified by experimental investigation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1608-1614
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• 2002

This Paper presents a novel piston friction force measurement system that has characteristics of relieving the Pressure force acting on the upper surface of the liner; the system uses general rubber O-rings for combustion chamber sealing, and does not need special changes to the piston top land. The lower supporter of the floating liner increases stiffness in liner axial direction, and results in the increase of natural frequency. The upper supporter has multi-layer structure designed fer low axial stiffness and high radial stiffness. With the use of the present system, the effects of variation in clearance and piston ring tension were studied.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.2
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• pp.17-23
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• 2004

The effects of refining consistency and plate gap on the specific energy consumption and physical properties of liner were investigated. Higher refining consistency and narrower plate gap brought about the reduction of specific energy consumption to decrease the freeness. Refining consistency and plate gap did not affect the bulk, Taber stiffness and compression index. The reduction of freeness and/or the increase of specific energy consumption caused the decrease of bulk and Taber stiffness, but increased the compression index. The effect of grammage on bulk was not observed, but Taber stiffness and compression index were increased with grammage. The bulk was decreased with the reduction of freeness rapidly at the above 400 mL CSF, and then levelled off. It is expected that the reduction of energy consumption could be obtained from the application of higher refining consistency and narrower plate gap during refining.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.327-328
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• 2010

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.273-280
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• 2003

This paper describes a study of the effect of shield tunnel construction on the liners of nearby existing perpendicular tunnels. The research programme investigated the influence of tunnel proximity and alignment, liner stiffness on the nature of the interactions between closely spaced tunnels in clay. A total of two sets of carefully controlled 1g physical model tests, including the same test for repeatability, were performed. A cylindrical test tank was developed and used to produce clay samples of Speswhite kaolin. In each of the tests, three model tunnels were installed in order to conduct two interaction experiments in one clay sample. The tunnel liners were installed using a model tunnelling machine that was designed and developed to simulate the construction of a full scale shield tunnel. The first tunnel liner was instrumented to investigate its behaviour due to the installation of each of the new tunnels. The interaction mechanisms observed from the physical model tests are discussed and interpreted.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.6
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• pp.113-122
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• 2003

Topology optimization is begun with layout optimization that is attributed to Rozvany and Prager of the 1960's. They claimed that structure was transformed into truss connecting all the nodes of finite element and optimized by control of its sectional modulus. But, this method is partial topology optimization. General layout optimal design appliable to continum structure was proposed by Bendsoe and Kikuchi in 1988. Topology optimization expresses material stiffness of structure into function of arbitrary variable. If this variable is 1, material exists but if this variable is 0, material doesn't exist. Therefore, topology optimization searches the distribution function of material stiffness for structure. There are a few researchs for simple engineering problem such as topology optimization of square plane structure or truss structure. So, This study applied to topology optimization of table liner for vertical roller mill that is the largest scale in the world. After table liner decreased by 20% of original weight, the structure analysis for first optimized model was performed.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.607-614
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• 2000

Settlement with crack on the hardened liners may occur in the weak clay due to waste load since the stiffness of the hardened liner is greater than that of the clay layers. Way of reducing deformation crack in the hardened liner is investigated using two computer programs, CONSOL and FLAC. The computer program CONSOL estimates the magnitude of settlement with time in clay layers and FLAC analyses the stress and deformation relationship between the foundation of landfill and waste load. The results show that a representative block of the analyzed area reaches the consolidation settlement of 1.32m, 8.8 years after the disposal of waste started with the degree of consolidation U=90%. The stress within the hardened liner exceeds the allowable vertical stress of 5kg/$\textrm{cm}^2$ and horizontal stress of 1.67kg/$\textrm{cm}^2$ at the concave part of the liner where the main and branch drainage pipes of leachate are located. It was recognized that the thickness of the interested area should be enlarged or the strength of the same area should be improved to tolerate the planned waste load.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.8 s.227
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• pp.1174-1182
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• 2004

Recently, Self Piercing Rivet(SPR) has been spotlighted in the automotive industry as a substitutive resort of spot welding and has also been watched by the designer as lightening a car body due to their superior assembly processes. Fatigue behavior of SPR joint needs to be investigated experimentally and numerically to predict its structural stiffness and fatigue life. Testing of lap-shear specimens with various material combinations is performed to obtain the joining strength and the fatigue life of SPR connections. The simulation of SPR lap-shear specimens is also conducted to obtain the structural stiffness of SPR connections under different material combinations. A Finite element model of the SPR lap-shear specimen is developed using a FEMFAT SPR pre-processor. The fatigue lift of SPR specimen is predicted using a FEMFAT 4.4e based on the liner finite element analysis.

• Geotechnical Engineering
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• v.12 no.3
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• pp.35-48
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• 1996

Reinforced soil structures may experience large local movements between soil and reinforcement. The failure modes of a reinforced structure depend on several factors which are governed by deformation and slipping of the reinforcement. In some cases, pulling out of the reinforcement may occur instead of rupturing, The growing use of geosynthetic liner system for storage of solid and liquid wastes has led to a number of slope instability problems where the synthetic liner may undergo a large amount of stretching and slipping as a result of the loading. The conventional finite element model for the soil-reinforcement interface uses a zero thickness joint element with normal and shear stiffnesses and can only accommodate a small amount of deformation. When a large slippage occurs, the model provides an i ncorrect mechanism for deformation. This paper presents a new interface finite element model which is able to simulate a large amount of slippage between soil and reinforcement. The formulation of the model is presented and the capability of the model is demonstrated using illustrative examples.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.181-187
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• 2003

This paper describes a study of the influence of shield tunnel construction on the displacements and stresses induced in the linings of existing nearby parallel tunnels. The paper presents a brief review of a set of laboratory scale model research programme investigating the influence of tunnel proximity and alignment, liner stiffness on the nature of the interactions between closely spaced tunnels in clay. A total of two sets of carefully controlled physical model tests were performed. A cylindrical test tank was developed and used to produce clay samples of Speswhite kaolin. In each of the tests, three model tunnels were installed in order to conduct two interaction exts that have been carried out to investigate the interaction problem between parallel tunnels. The results of these tests are compared with the results of finite element analysis to investigate the techniques that must be used to obtain reliable numerical solutions to this type of problem.