• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.940-945
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• 2010

There are human casualties that caused by slope-stability related disasters such as landslide and debris flow during typhoon and rainy season every year in Korea. These disaster sites can be analyzed systematically using digital topographic data and aerial photogrammetry. In this study, geographical factors such as slope degree, geology, height, and soil depth are analyzed in four landslide-disaster sites from Muju, Jinan, and Jangsu County based on digital elevation maps generated by ArcGIS. Each site showed different characteristics in geology and geography and it is found that GIS can be utilized for the visualization of steep-slope failure areas.

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.3
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• pp.68-77
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• 1994

TIG welding process is applied for the active metal such as aluminum and titanium, also sometimes for overlay welding of superalloy. However the welding speed to be applied is very low because of the unstable bead formed in the region of high current and high welding speed. The present study was carried out to examine the basic phenomena of high speed TIG melt run welding by the 2% Th - W electrode(dia.3.2mm) of various tip shapes.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.186-194
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• 2003

This paper proposes a combined controller frame of the adaptive robust control(ARC) and the sliding mode control(SMC) for the trajectory tracking control of the excavator to preserve the advantages of the both methods while overcoming their drawbacks, namely, asymptotic stability of adaptive system fir parametric uncertainties and guaranteed transient performance of sliding mode control for both parametric uncertainties and external disturbance. The suggested control technique is applied for the tracking of a straight-line motion of end-effector of manipulators, and through computer simulations, its trajectory tracking performances and the robustness to payload variation and uncertainties are illustrated.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.737-738
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• 2002

To develop and improve a GIS(Gas Insulated Switchgear), the prediction of the pressure in puffer cylinder and the flow between the nozzle and the moving electrode within GIS is very important.The leading companies in GIS business issue the results of the study of flow within GIS including arc plasma. In this study, the characteristics of the flow of the GIS developed by HHI(Hyundai Heavy Industries Co. Ltd.) was investigated. To simulate the compressible flow of GIS, the CFX, a commercial CFD code, was used. With moving grid method, the movement of piston and electrode was simulated. The moving grid method was superior to the method of varying the property of cells to move an obsticle, in stability and convergencce of solution. The calculated maximum pressure within the puffer cylinder was matched with experimental data within $5{\%}$ error. The oscilation of pressure in GIS after the movement of electrode was well predicted.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.05a
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• pp.275-278
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• 2004

This paper focused on problems of design, construction, and maintenance caused by construction implementation processes. They were analyzed through case study of structure safety diagnosis projects. From the case study, it is expected that the introduction of Construction Management from the first stage of procurement will improve construction cost increase or burden on small design company. It strengthens coherent management from design and source contractor selection to build review of responsibility. The coherency will prevent changes in designing or infirm unreliable construction. It is desirable that expert opinions are considered when structure changes and establishment occur and that, if necessary, actions such as source selection, periodic audits, and diagnosis arc checked and fed back to maintenance.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.496-503
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• 2003

Recently, the buckling is easy to happen a thin plate and High Tensile Steel is used at the structure so that it is wide. Especially, the buckling is becoming important design criteria in the ship structure to use especially the High Tensile Steel. Consequently, it is important that we grasp the conduct after the buckling behaviour accurately at the stability of the body of ship structure. In this study, examined closely about conduct and secondary buckling after initial buckling of thin plate structure which receive compressive load according to various kinds aspect ratio under simply supported condition that make by buckling formula in each payment in advance rule to place which is representative construction of hull. Analysis method is F.E.M by ANSYS and complicated nonlinear behaviour to analyze such as secondary buckling.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.498-506
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• 2010

The neutral section was installed in order to prevent conflict with different phase angle source in electric railway catenary system. The speed of electric train reduced due to coasting operation by notch off when it passed the neutral section. And, the catenary wire was damaged and the accident might be happened because of the arc generation when the electric train passed the neutral section with notch on condition. This project has a goal to develop the automatic changeover system using by noncontactless semiconductor device in neutral section of catenary system so that the train pass as notch-on condition. In this first year, we obtain as following results such as domestic and international systems applications and completion requirements, development and analysis of stability for automatic changeover system, design of static switching device on automatic changeover system in neutral section and drawing up interface design and specifications according to equipment.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.1
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• pp.22-29
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• 2004

This paper studies the coordinated trajectory control of an excavator as a kind of robotic manipulators driven by hydraulic actuators. Hydraulic robot system has many non-linearity in dynamics and kinematics, and strong coupling among joints(or hydraulic cylinders). This paper proposes a combined controller frame of the adaptive robust control(ARC) and the sliding mode control(SMC) for the trajectory tracking control of the excavator to preserve the advantages of the both methods while overcoming their drawbacks, namely, asymptotic stability of adaptive system for parametric uncertainties and guaranteed transient performance of sliding mode control for both parametric uncertainties and external disturbance. The suggested control technique is applied for the tracking of a straight-line motion of end-effector of manipulators, and through computer simulations, its trajectory tracking performances and the robustness to payload variation and uncertainties are illustrated.

• Journal of Korea Foundry Society
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• v.17 no.1
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• pp.85-92
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• 1997

There has been a considerable interest to develop the silicide alloys as high temperature structural materials because of their excellent high temperature stability and strength, however, their lack of room temperature ductility and toughness was a main obstacle for the application. In order to improve ductility while maintaining good high temperature properties, possible refractory metal-silicide eutectic alloys composed of fine two phases were prepared by VAR(Vacuum Arc Remelting). Three silicide alloys, $Nb-Nb_3Si$, $Ti-Ti_5Si_3$, $V-V_3Si$, were selected as prospecting silicide eutectics and those high temperature characteristics were evaluated by high temperature compression test.

• The Korean Journal of Food And Nutrition
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• v.9 no.2
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• pp.143-150
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• 1996

The studies was carried out to investigate ripening degree and functional properties of EMC produced with pancreatic protease and palatase ML. During production of EMC, the amounts of free amino acid and free fatty acid were increased with increasing the reaction time. The amount of total nitrogen(T-N) and water soluble nitrogen(WSN) were increased with increasing time. EMC had contents of 1.79eA T-N and 0.52o WSN at 60 min of hydrolysis time. SRI and FRI value had also a similar correlationship. On the gel filtration, 2 kinds of soluble proteining capacity was also shown in alkali solution. Furthermore the foaming stability had the same result as that of the solubility. The water absorption of EMC showed the highest level at pH 4.0 and 5.0.