• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.102-103
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• 2014

Due to the nature of the existing load, the criteria of assessing the intensity of the lightweight wall's impact resistance has been though of as obscure. The current study, therefore, focuses on the standardized assessment of the impact resistance to the force of the large soft body applying to the lightweight wall. The gypsum board wall showed a low level of the maximum residual displacement. It is, however, required to be careful about the selection of the finishing process since the high level of the maximum displacement is likely to cause harm to finishing materials. Unlike the gypsum board, the ALC block wall displayed a considerable rigidity while showing almost no maximum residual displacement. Even with the low level of the maximum displacement due to the stiffness, the ALC block wall is still likely to be affected by the vibration derived from any impact on the surface, which demands a need for additional study. The future experimental study, accordingly, will focus on the impact of the vibration on finishing materials, consequently leading to the accurate prediction of the possibility of potential damage to the lightweight wall caused by the large soft body.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1273-1276
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• 2005

A displacement magnification mechanism is usually employed in a nano-positioning stage to achieve a large stage motion. A lever mechanism is the most widely used displacement magnifying mechanism. For more large stage motion, double or multiple lever mechanisms can be used. In this case, a more accurate analysis model is needed. This study proposes a more reasonable analysis model for a multiple lever mechanism based on the single lever mechanism model. This paper describes that the high equivalent stiffness of the lever is the most important factor reducing the magnification ratio of the lever mechanism through increasing the deflection of the link and including the axial displacement of the pivot.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.281-288
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• 2000

In this study, we tried to determine failure criteria for joints of soft rock using ring shear test machine. The residual stress fellowing shear behavior was determined by the result of ring shear test and direct shear test. Ring shear test with the specimens which cover a large deformation range was adapted to measure a residual stress, and was possible to present the peak stress to present the peak stress to the residual stress at the same time. Residual stress is defined a minimal stress of specimens with a large displacement and the result of the peak residual stress is shown by a size of displacement volume. Therefore, the residual stress in soil was decided by shear stress of maximum shear stress - shear displacement(angle) based on the test result of a hyperbolic function ((equation omitted), a, b ＝ experimental constant). In this study, it was proved that the residual stress of rock joint can be determined by using of this method.

• Structural Engineering and Mechanics
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• v.7 no.1
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• pp.111-126
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• 1999

The work presented here focuses on the development of suitable discretised formulations, for large-displacement shape and non-shape design sensitivity analysis (DSA), which enable the straightforward incorporation of structural optimisation into established finite element analysis (FEA) codes. For the generalised displacement-based functional the design sensitivity vector has been expressed in terms of displacement sensitivity. The Total Lagrangian formulation is utilised for modelling of large deformation of truss structures. The variational formulation of the sensitivity analysis procedure is discretised by using "pseudo" - finite elements, Results are presented for the sensitivity analysis and optimisation of standard truss structures. For the purposes of this work, the analysis and optimisation procedures outlined below are incorporated into the FEA code ABAQUS.

• Journal of Korean Association for Spatial Structures
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• v.20 no.4
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• pp.83-91
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• 2020

In this study, a tuned mass damper(TMD) was installed to control the displacement response to earthquakes by generalizing to six analysis models according to the shape of the upper structure based on the case of various large spatial structures around the world. The six analysis models are ribbed type, latticed type, elliptical type, gable type, barrel type, and stadium type composed of 3D arch trusses. In this paper, ribbed type, latticed type and elliptical type were analyzed. The mass of each TMD was set to 1% of the total structural mass. Result of analyzing the optimal number and position of the analysis model, the displacement response control was the most excellent in the model with 6 and 8 TMDs, and the displacement response decreased in most cases. The displacement response control was better with installing the TMD at the edge point than focusing the TMD at the center of the analysis model. However, when 10 or more TMDs are installed or concentrated in the center, large loads intensively act on the structure, resulting in increased displacement. Therefore, although it is slightly different depending on the shape, it is judged that the displacement response control is the best to install 6 and 8 TMDs at the close to the edge point.

• Journal of Korean Association for Spatial Structures
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• v.20 no.4
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• pp.73-81
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• 2020

In this study, a tuned mass damper(TMD) was installed to control the displacement response to earthquakes by generalizing to six analysis models according to the shape of the upper structure based on the case of various large spatial structures around the world. The six analysis models are ribbed type, latticed type, elliptical type, gable type, barrel type, and stadium type composed of 3D arch trusses. In this paper, ribbed type, latticed type and elliptical type were analyzed. The mass of each TMD was set to 1% of the total structural mass. Result of analyzing the optimal number and position of the analysis model, the displacement response control was the most excellent in the model with 6 and 8 TMDs, and the displacement response decreased in most cases. The displacement response control was better with installing the TMD at the edge point than focusing the TMD at the center of the analysis model. However, when 10 or more TMDs are installed or concentrated in the center, large loads intensively act on the structure, resulting in increased displacement. Therefore, although it is slightly different depending on the shape, it is judged that the displacement response control is the best to install 6 and 8 TMDs at the close to the edge point.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.667-668
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• 2009

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.484-489
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• 1998

In this paper, we examine the displacement characteristics of the parallel leaf spring mechanism with large-deflective elastic hinges, and the validity of this mechanism as a translational and rotational mechanism is confirmed with multi-input system. This study is focused on the linear driving force as an input force, which is applied to the large-deflective elastic mechanism, and the displacement characteristics are discussed with theoretically and experimentally. The motions of this mechanism due to large-deflective hinges are changed by the position of loading force regardless of a single driving force. The numbers of degree of freedom are increased with the hinges, and we can be used to a multiple driving force in order to obtain many types of Output.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1626-1631
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• 2007

The purpose of the study is to simulate the displacement of the LCD glass during process of a large size imprint. During this process, a small temperature variation makes thermal stress, which causes the horizontal variation of mold and glass. During alignment process to fix the LCD glass on a alignment stage, the vertical displacement is made by the absorption pressure and the shear stress. This study simulates the horizontal displacement of mold and glass due to temperature variation, the vertical displacement depending on the shape of absorption surface fixing the LCD glass in the alignment process, and the horizontal and vertical displacement which occurs in the LCD glass at the alignment process. Algor which is a FEM code for a framework simulation was applied. Temperature variation above ${\pm}$ $0.1^{\circ}C$ on mold and glass causes the horizontal displacement of 150nm due to thermal expansion. The vertical displacement due to the circular is ten times of the case of rectangular absorption nozzle. The displacement of the LCD glass in the alignment process is about 49nm.

• Journal of Korean Association for Spatial Structures
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• v.21 no.1
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• pp.95-104
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• 2021

As people's living standards and cultural standards have developed, interest in culture and art has increased, and the demand for large space structures where people can enjoy art, music, and sports has increased. As it accommodates a large number of personnel, it is most important to ensure safety of large spatial structures, and can be used as a space where people can evacuate in case of a disaster. Large spatial structures should be prepared for earthquake loads rather than wind loads. In addition to damage to the structure due to earthquakes, there are cases in which it was not utilized as a space for evacuation due to the fall of objects installed on top of the structure. Therefore, in this study, the dome-shaped large spatial structure is generalized and the displacement response according to the number of installations, position and mass is analyzed using a tuned mass damper(TMD) that is representative vibration control device.