• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.108-108
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• 2004

전동차의 차체는 최대승객하중의 운행조건 하에서 시스템의 기능을 만족하도록 강성 및 강도를 갖도록 되어 있으며, 수직하중 및 수평하중을 지지하는 언더프레임(Under Frame), 측벽의 하중을 지지하는 측면구조틀(Side Frame) 지붕을 구성하는 지붕구조틀(Roof Frame), 끝막이 골조(End Frame)로 구성되어 있다.(중략)

• Journal of Korean Association for Spatial Structures
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• v.10 no.2
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• pp.69-76
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• 2010

After obtaining tensile and compressive stiffness as well as shear stiffness of elastomeric seismic isolator experimentally, those stiffness were modeled analytically using nonlinear computer program. To induce tensile stress due to overturning in the seismic isolators of an isolated frame for horizontal force, free vibration simulations generated by large initial displacement were conducted. Since elastomeric seismic isolator is weak for tensile stress, the axial stiffness of isolators shall be included properly in the analytical model to evaluate the uplift phenomenon of elastomeric seismic isolator.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.533-540
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• 2012

Rubber laminated bearings with lead core are highly affected by changes in temperature because key materials which are rubber and lead have temperature dependencies. In this study, two full scale LRB(D800, S=5) are manufactured and temperature dependency tests on shear properties are accomplished. The shear properties at the 3rd cycle are used at $-10^{\circ}C$, $0^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$ respectively. The double shear configuration, simultaneously testing two pieces, is applied for compression shear test in order to minimize the friction effects due to the test machine, described in ISO 22762-1:2010. Characteristic strength, post-yield stiffness, effective stiffness, equivalent damping ratio are estimated and presented coefficient due to the temperature changes.

• Journal of the Korean Society for Railway
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• v.18 no.2
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• pp.139-148
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• 2015

By increasing the vertical stiffness of the rail fastening system, the dynamic wheel load of the vehicle can be increased on the ballast track, though this increases the cost of track maintenance. On the other hand, the resistance acting on the wheel is decreased, which lowers the cost of the electric power to run the train. For this reason, the determination of the optimal fastener stiffness is important when attempting to minimize the economic costs associated with both track maintenance and energy to operate the train. In this study, a numerical method for evaluating the optimal vertical stiffness of the fasteners used on ballast track is presented on the basis of the process proposed by L$\acute{o}$pez-Pita et al. They used an approximation formula while calculating the dynamic wheel load. The evaluated fastener stiffness is mainly affected by the calculated dynamic wheel load. In this study, the dynamic wheel load is more precisely evaluated with an advanced vehicle-track interaction model. An appropriate range of the stiffness of the fastener applicable to the design of ballast track along domestic high-speed lines is proposed.

• Journal of Korean Society of Steel Construction
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• v.16 no.5 s.72
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• pp.629-639
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• 2004

A steel frame is one of the most commonly used structural systems due to its resistance to various types of applied loads. Many studies have been conducted to investigate the effects of several parameters, such as connection flexibility, the boundary condition of each support, and beam-to-column stiffness ratio, on the characteristic behavior of a frame. Based on the results of these studies, several design methods have been proposed. This research focused on the number of bolts on the rotational stiffness of a double-angle connection, and its effect on the story drift of a frame. To achieve these purposes, a simplified analytical model was proposed. Several experimental tests were also conducted to obtain the rotational connection stiffness of each double-angle connection.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.409-416
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• 2002

In order to apply seismic isolators to the low-cost buildings, seismic isolators have to be low-cost and light. In this paper fiber reinforced strip form isolator in which the steel plates of conventional rubber bearing was replaced by fiber was proposed. The proposed fiber reinforced strip form isolator was designed, fabricated, cut and subjected to vertical test and harizontal test. Therefore fiber reinforced strip form isolator was to be shown valid in the view point of fabrication and application to desired size. The harizontal test and vertical test have shown that fiber reinforced strip form isolator could replace the rubber isolator. By these results, low-cost and light seismic isolator can be applied to the low-cost building. These fiber reinforced strip form isolator can be applied to the low-cost building.

• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.6
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• pp.1-6
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• 2002

In order to apply seismic isolators to low-cost buildings, seismic isolators have to be low-cost and light. In this paper fiber reinforced strip form isolator in which the steel plates of conventional rubber bearing were replaced by fiber was proposed. The proposed fiber reinforced strip form isolator was designed, fabricated, cut and subjected to vertical test and horizontal test. Therefore, fiber reinforced strip form isolator was to be shown valid in the view point of fabrication and application to desired size. The horizontal test and vertical test have shown that fiber reinforce strip form isolator could be replaced the rubber isolator. By these results, low-cost and light seismic isolator can be applied to the low-cost building.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.4
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• pp.443-451
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• 2007

The improvement of stiffness by the increase of thickness of deck plate or the reinforcement of longitudinal rib is one method among the effective methods to control fatigue damages occurring in orthotropic steel deck. It is likely that the increase of stiffness is effective to restrain local deformation caused by axial load in the steel deck. Therefore, in this study, the parameter studies for the reinforced structural details such as the bulk-head plate and vertical rib which is established to reduce the resultant stresses in the connection parts of the longitudinal rib and floor beam were performed with FE analysis. From the results, it was known that the reinforced structural detail with the bulk-head plate in the longitudinal ribs reduced overall the principal stresses at the connection parts, but the stress concentration increased in the weld toe parts which are occurring fatigue cracks. Also, it was estimated that the reinforced structural detail with the vortical rib in the longitudinal ribs because of the reduction of stress concentration in the weld toe parts is more effective details than the bulk-head plate.

• Tunnel and Underground Space
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• v.8 no.4
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• pp.342-350
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• 1998

In this study, fracture network in rock mass was interpreted using borehole wall images obtained by televiewer. The orientation and JRC value of major joint set were evaluated adopting image analysis techniques, of which process were written in macro-program code. As linking JRC to joint stiffness using Barton-Bandis model, fracture network map was produced for application to jointed rock modelling in numerical analysis of underground structure.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.591-592
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• 2023

본 논문에서는 다양한 시장 요구사항에 따른 공간적 효율성과 유연한 관리 시스템이 내장된 스마트 적재창고를 제안한다. 적재창고는 공간 활동의 최적화를 요구하는 동시에 높은 수준의 비용 효율성을 갖추어야 한다. 그리고 자동화된 애플리케이션이 기존 창고 및 공급만 운영보다 중요하며 스마트 팩초리와 연계하여 부품 재고파악과 입출고를 효율적으로 담당해야 한다. 본 논문에서는 수직강성을 최대 300kg를 견딜 수 있는 수직형 자동적재창고를 구현한다. 연구의 결과는 스마트팩토리 등의 자동화 장비 구축을 통한 생산성 향상에 도움이 될 것으로 사료된다.