• Korean Journal of Metals and Materials
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• v.48 no.6
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• pp.551-556
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• 2010

In this report, we describe mold materials that were used to produce movable metal type by the investment casting method during the Joseon dynasty period in Korea. Samples were obtained from the Wibuinja collection, which is held by the National Museum of Korea. Most of the mold material remnants were found in the depressed areas of the movable type specimens, and we therefore performed non-destructive analyses including XRF, EDS, and XRD. Through these analyses, we were able to identify the mold remnants as hydrocerussite [trilead dihydroxide dicarbonate, $Pb_3(CO_3)_2(OH)_2$] formed in platy hexagonal crystallites. Hydrocerussite was first used to make white pigments and cosmetics in ancient Greece, but this is the first report of hydrocerussite used as mold material applied around a disposable pattern for investment casting. The results of this study will further the understanding of the production process for early movable metal type and ancient casting technologies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.31-33
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• 2012

Movable scaffolding has been used to work in high places. The scaffolding is economical and convenient to move to other places, but it has the risk of falling down. This paper proposes a fixed bracing system to prevent the falling down of a movable scaffolding, and evaluates its usability by making a small-sized model. Further studies of structural stability, safety, and economical efficiency is necessary to use the system practically.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.373-380
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• 1998

3D finite element analyses of movable bearing shoe and hinged bearing shoe are performed. The finite element models are built using MSC/PATRAN and analyses are carried out using MSC/NASTRAN. Results are again completely processed using MSC/PATRAN. From the results of the analyses, trends of deformation and stress distribution are reviewed and important factors to consider in the design of bearing shoes are discussed. Furthermore optimum crowning amount for the roller of movable bearing shoe was determined according to the results of the analyses.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.287-296
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• 2011

Turnout is a mechanical installation enabling railway trains to be guided from one track to another at a railway junction. A movable nose crossing frog is a device used at a railway turnout to eliminate the gap at the common crossing (High manganese, block, assembly crossing)which can cause impact damage, noise and vibration. Our government has a plan speed up of conventional line to 250km/h semi-high speed. We had already developed flexible turnout with fixed crossing(High manganese) and SFC fastening system can cover in the semi-high speed line In this study is about development of the movable nose crossing turnout available Semi-high speed line on concrete track. This paper describes about geometry, attack angle, bending stress at the nose, switching force, safety of continuous welded long rails. This movable nose crossing turnout is expected greatly increases passing speed of turnout in national railway.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.5
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• pp.474-479
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• 2013

Mass reduction of the machine tool movable parts is a tool for achieving lower energy demands of the machine tool operation. The realization of lightweight design in machine tool can be achieved by structural lightweight design and material lightweight design. In this study, topology optimization strategy was applied to design optimized structures of movable parts of 5 axis machining center. The weight of ram which has most significant influence on the stiffness of whole machine tool was reduced without stiffness deterioration. The redesigned optimized ram has 24.2% less weight while maintaining the same displacement caused by cutting force.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.7
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• pp.51-57
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• 1999

Recently, long large bridges are built for mass transportation. Movable bearing shoes are important components of the bridges because they support movement of translation and rotation of bridge. In design stage of the long large bridges, detailed analyses using the finite element method are performed to guarantee safety and reliability. For that purpose, three-dimensional modeling is carried out by I-DEAS software and finite element analysis by ANSYS software. Results of the analyses are reviewed and important design factors for movable bearing shoes are discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.813-817
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• 1995

Structural analysis of horizontal cold chamber die casting machine is performed by the FEM. The analyzed model is made up of stationary die platen,movable die platen,link housing platen, C-frame, and tie bar which mainly undertake die locking force and injection force. In modeling, compression gap elements are used for to simulate contacting condition between tie bar and movable die platen, movable die platen and base frame, and link housing and base frame. Unbalanced die locking force imposed on four tie bars are considered. As the results, the deformed shape and the stresses of the die casting machine are given.

• Journal of Power System Engineering
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• v.17 no.1
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• pp.85-90
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• 2013

Dry CVT consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The important claim which have an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study ball type is proposed instead of roller type of movable flange to resolve the claim. Simulation is carried out for new model to verificate performance, experiments are carried out for new model to evaluate performances.

• Advances in concrete construction
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• v.4 no.3
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• pp.173-194
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• 2016

This paper consists in a study of a new contructive sequence of road viaducts with Movable Scaffolding System (MSS) using numerical tools based on finite element method (FEM). Traditional and new sequences are being used in Spain to build viaducts with MSS. The new sequence permits an easier construction of one span per week but implies some other issues related to the need of two prestressing stages per span. In order to improve the efficiency of the new sequence by reducing the number of prestressing stages per span, two solutions are suggested in this study. Results show that the best solution is to introduce the 100% of the prestressing force at the self-supporting core in order to improve the road viaduct construction with movable scaffolding system by reducing execution time without increasing economic costs.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.219-222
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• 2007

The Full-Off Fitting of Movable Bracket using conventional line have received a dynamic contact impact between contact wire and pantograph of electric rolling stock, so this impact cause a rapid vibration of foreword and back near the supporting point of movable bracket. The Full-Off Fitting on Movable Bracket in conventional line differs from that in high speed line. Now conventional line have required a speed up for new electric locomotive and electric car. In speed-up track and big impact place, the Full-Off Fitting and the dropper often get demage. We have done a study of buffering function to solve that problem in conventional line. We have find a need adopting buffer fitting. It is decrease a dynamic impact between contact wire and pantograph of electric rolling stock.