• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.619-620
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.826-830
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• 1996

The pneumaic systems are widely applied to chemical factory of fire dangry and factory automation. by using compressed air, it is difficult to dynamics action analysis that the pneumatics system acts to nonlinear motion through orifices and valve flow. This paper was studied to a nonlinear chararistics of pneumaic spring, damper and absorber of pneumaic cushion cylinder.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.737-738
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• 2013

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.508-511
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• 2008

The most landing gear use oleo-pneumatic shock strut to absorb the impact energy during touchdown. The shock strut is composed of the oil damper and the gas spring, especially the oil damper provides resistance force which is proportional to the square of landing speed. In case of high landing speed, the abnormal peak load can be occurred and transferred to the airframe structure. To prevent this, the pressure-relief valve is used to limit the damping force under the specific level. In this paper, it is presented the design process to find optimal damping and analysis results using pressure-relief valve.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.153-158
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• 2019

The overall environmental regulations of the industry have been strengthened due to environmental pollution that occurred in modern society. Therefore, R&D of selective reduction catalyst (SCR) is needed to meet these environmental regulations. This paper carried out thermal analysis to develop the pneumatic damper valve (PDV), which is a key component of SCR system. For thermal analysis, verification of material properties was performed first. Verification was performed through the thermal properties test and the thermal tensile test of the specimen, and the results were reinforced with the material properties to enhance the reliability of the thermal analysis.The heat analysis was intended to identify thermal characteristics with PDV in total of three materials (SM400B, SS275, SB410) applied under the conditions of use of PDV, and to confirm the structural stability of the PDV.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.4
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• pp.135-143
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• 2003

In this study, a real-time simulation model was developed for tracked vehicles with in-arm type semi-active hydro-pneumatic suspension unit using MATLAB S-functions. Since the vehicle model uses relative coordinates and massless link elements, the developed model has an enhanced analytic time performance. Through the comparison of simulation results with multi-body software(DADS), the vehicle model is verified. A controller using on-off skyhook control algorithm is designed with the pilot-centre]led proportional valve based on conventional damper characteristics. Exploiting the developed tracked vehicle model with other subsystem model such as a controller model, a suspension unit model, and a test road model, computer simulations are carried out. Control simulation results with the developed tracked vehicle model show that the semi-active suspension control system has a better performance than the conventional suspension system.