• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.289-295
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• 2005

LMTT (Linear Motor-based Transfer Techn-ology) is a horizontal transfer system for the yard automation This system is based on PMLSM (Permanent Magnetic Linear Synchronous Motor) toot consists of stator modules on the rail and shuttle car. In this research, the kriging interpolation method with sequential sampling find the optimum design of mover in LMTT. The design variables are considered as the transverse, longitudinal and wheel beam's thicknesses. The objective function is set up as weight, while the constant function are set up as the stresses generated by four loading conditions. The objective function is set up as weight. The optimum results obtained by the suggested method are compared with those by the GENESIS.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.65-70
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• 2008

The numerical simulation on the internal flow characteristics of the adaptor in a two-fluid nozzle has been performed to investigate the effects of carrier air supplying parameters using a commercial code. The four adaptor models with the different positions in the carrier air supplying port were considered at the fixed conditions of urea-water solution and carrier air supplying. As the results from the numerical analysis, the internal pressure of the adaptor was varied with the port position for carrier air supplying, and it shows lower pressure value than the atmospheric pressure. Consequently, the flowrate of urea-water solution issuing from the feeding injector with the adaptor varied up to 30% with the port positions for the carrier air supplying. When the carrier air is supplied from the side from the feeding injector axis and the upper part from the feeding injector tip, the flowrate of urea-water solution issuing from the feeding injector with the adaptor show higher value than other carrier air supplying conditions.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.387-390
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• 2006

Conventional spinning, shear forming and flow forming techniques are being utilized increasingly due to the great flexibility provided for producing complicated parts, enabling customers to optimize designs and reduce weight and cost, all of which are vital, especially in automotive industries, space shuttle, a munitions industry. The deformation mechanism of conventional spinning and shear forming is studied in this paper through analysis. The forming loads of a spin formed dome in an Al launch vehicle fuel tank was studied analysis and a simple FE model to predict the forming loads of the dome was proposed. The analysis is carried out to study the effects of feed rates and thickness reduction on material flow.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.410-415
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• 2004

Heavy-weight head slides may cause excessive inertia impact ＆ moment on the machine tool structure when they move or stop abruptly during operation. Consequently these inertia impact and unbalanced moment bring transient vibrations and rough sliding motions on the machine structure. Machine tool engineers have tried many kind of feed-slide designs in order to solve this problem; for example, the design optimization of the moving structure for minimum weight and maximum stiffness, box-in-box type slide design, and so on. In this article, force and moment equilibrium equations regarding to the inertia force ＆ moment were derived for each one of a mold M/C's head slides. Furthermore, five different design configurations of head slide assembly were reviewed for its design improvement regarding to force ＆ moment calculations and finite element structural analysis results.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.618-622
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• 2006

충적 선상지(alluvial fan)는 자갈이나 유사가 과도하게 이송되어 부채모양으로 퇴적된 것으로서, 하류로 하폭이 증가하는 곳에서 형성된다. 충적 선상지는 유사가 이송하는 하천, 토석류, 그리고 박층류에 의해 형성된다. 토석류는 자갈에서부터 상대적으로 작은 진흙에 이르기까지 운반하는 밀도체이다. 충적하천의 흐름은 사행하천 및 망상하천에 이르는 흐름을 말하며, 박층류는 기본적으로 비하천 홍수류로서, 한 홍수사상에 대하여 선상지에서 부분분할로 형태로 흐른다. 본 연구에서는 충적 선상지에 대한 공학적인 문제를 검토하기 위한 예비연구로서 유입부에서 유사량의 유입조건에 따른 충적 선상지 델타의 형성 과정을 수치모형을 이용하여 파악하였다. 본 모형은 2차원 모형으로서, 이동경계좌표계를 사용하였고, 수치해석 기법으로는 CIP법이 이용되었으며, wet/dry를 고려하여, 유입 유사량의 변화에 따른 특성을 파악하였다. 초기에는 급격하게 선상지의 높이가 급격하게 증가하며, 유입 유사량의 증가에 따라 선상지의 높이가 평형상태를 유지하는 시간이 짧은 것을 보여주고 있다. 선상지의 면적은 유입 유사량이 적을 경우에는 평형상태가 지속적으로 유지되며, 완만한 증가 현상을 보여주었다. 유입 유사량이 증가할 경우에는 초기에 급격한 상승을 하다가 평형상태가 없이 지속적으로 상승하는 것을 보여주었다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.87-87
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• 2012

아라미드 레노직물은 컨베이어벨트, 건조벨트, 스크림직물, 전자산업용 이송체 등 여러 산업분야에 사용되고 있다. 레노는 2D 구조의 메쉬 형태 직물이고 치수안정성이 낮다. 그렇기 때문에 치수안정성을 부여할 수 있는 후가공이 필요하며, 현재는 치수안정성을 부여하고 여러 물성보완과 내수성을 향상시키기 위해 PTFE(Polytetrafluoroethylene) 코팅을 하고 있다. 우리는 이러한 PTFE코팅의 영향을 분석하기 위해 강도, 탄성률, 열팽창계수, 내산성 등을 분석하였고, 그 결과 강도와 탄성률, 열팽창계수, 내산성 등이 PTFE 코팅에 의해 향상된 것을 알 수 있었다. 이는 PTFE 코팅에 의해 형태안정성이 향상되었고, 동시에 열적 안정성이 향상되었기 때문인 것으로 판단된다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.3
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• pp.221-227
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• 2002

The longitudinal and lateral in-plane vibrations of an axially moving membrane are investigated when the membrane has translating acceleration. By extended Hamilton's principle, the governing equations are derived. The equations of motion for the in-plane vibrations are linear and coupled. These equations are discretized by using the Galerkin approximation method after they are transformed into the variational equations, j.e., the weak forms so that the admissible functions can be used for the bases of the in-plane deflections. With the discretized equations for the in-plane vibrations, the natural frequencies and the time histories of the deflections are obtained.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.613-617
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• 2001

The longitudinal vibration of an axially moving membrane is studied when the membrane has translating acceleration. The equation for the longitudinal vibration is linear and coupled, The equation for the longitudinal vibration are discretized by using the Galerkin approximation after they are transformed into the variational equations, i.e., the weak forms so that the admissible function can be used for the bases of the longitudinal deflection. With the discretized equations for the longitudinal vibration, the time responses are investigated by using newmark method.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1634-1635
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• 2007

본 논문은 갠트리 크레인의 시뮬레이터를 제작하여 적응형 흔들림 제어기를 설계한다. 흔들림 감지는 디지털 카메라 센서를 이용하였으며 모델기반 적응제어를 이용하여 제어규칙을 산출한다. 제어규칙은 리아푸노브 안정성이론을 적용하였으며 정의된 리아푸노브 함수의 미분식이 음수를 갖기 위한 크레인의 적응형 제어입력을 계산한다. 제안한 제어기의 성능을 검토하기 위하여 실시간 제어실험을 실시하였으며 이송체의 무게 변화에 대한 적응성을 검토한다. 또한 기존의 PI 제어기도 함께 실험하여 성능의 비교 검토한다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.192-195
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• 2005

Nanometer operating linear motor is difficult to control the nano-positioning because of the vibration between structures changing of mechanical friction force happened by properties of the vibration and heat caused by operating of a mover. Therefore, it is required to analysis the vibration and heat about a mover. In this paper, we will analyze the property of vibration through analyzing by using FEM a mover of linear motor developed in the non-load situation and suggest the direction of optimal design about a mover by using method of DOE, also try to find the solution to operate the linear motor stabilized through the reducing weight of mover considering the vibration.