• Korean Journal of Heritage: History & Science
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• v.39
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• pp.243-280
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• 2006

At the Bujang-ri Site, Seosan, South Chungcheong Province, around 220 archaeological features, including semi-subterranean houses and pits of Bronze Age and semi-subterranean houses, pits, and burials of Baekje period had been identified and investigated. In Particular, mound burials No. 5 of 13 of Baekje mound burials yielding a gilt-bronze cap along with other valuable artifacts drew international scholarly attention. The gilt-bronze cap from the mound burial No. 5 is a significant archaeological data not only in the study of Baekje archaeology but also in the study of international affairs and exchange at that time. At the time of exposure, the gilt-bronze cap was already broken into a number of pieces and seriously damaged by corrosion, and hardening and urethane foam were necessary in the process of collecting its pieces. Ahead of main conservational treatments on cap, X-ray photograph and CT(computerizes tomography) were taken in order to examine interior structure of the cap and to decide appropriate treatments. In the five layers identified in the profile of cap, a textile layer was set between a metal and a layerof bark of paper birch for avoiding direct contact of the metal and the bark of paper birch. Analyses were executed for examining textile layer and a layer of fibroid material. According to microscopic analysis, while the textile layer consisted of the simplest plain fabric with one fold among three kinds of textile structures, the layer of fibroid material was mixed with two or three kinds of fibers. A comparative analysis with standard sample using FT-IR (Fourier Transform Infrared Spectroscopy) announced that both textiles and fabrics were hemp. Analysis of kind of the paper birch resulted in barks of paper birch with 15 fold. A metallographic microscope, SEM, and WDS were used for the analysis of microscopic structures of plated metal pieces. While amalgam plating was treated as a plating method, the thickness of the plated layer, a barometer of plating technique, was ranged from $1.72{\mu}m$ to $8.67{\mu}m$. The degree of purity of gold (Au) used in plating was 98% in average, and less than 1% of silver (Ag) was included.

• Journal of Technologic Dentistry
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• v.5 no.1
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• pp.27-30
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• 1983

This study was undertaken to know the difference that margin fittness in metal bond porcelain crown. When we use porcelain precious metal and non-precious metal as porcelain-fused metal, the results were as following. 1. The precious metal was showed best result in margin fittness and shade. 2. The non-precious metals were showed good results, especially Gemini II was excellent, but that was not good than precious metal. 3. 10k. gold plating on non-precious metal cap showed same result as nonprecious metal in margin fittness, and not good in shade. 4. When we use the non-precious metals at upper part of crown, and using precious metal in 2mm cervical portion, the margin fittness were very good, and the results same as full veneer precious metal.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1355-1359
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• 2010

The application of metal caps has been continuously increased as real life are extended. Metal caps is usually made of aluminum and polyethylene(PE) as packing. Since metal caps contain 75% aluminum on a weight basis, metal caps may be a valuable source when these were properly recovered. The recovery methods of metal caps have mechanical peeling and incineration. However these are either hard to apply in some case or environmentally unacceptable. So in this investigation, recovery method of aluminum from metal caps was investigated using pyrolysis. The result shows that pyrolysis temperature and pyrolysis time was $450^{\circ}C$ and 120min. respectively. Also 100% of aluminum was recovered from metal caps. Heat content of recovered oil was high enough to use as a fuel representing 7,425.0, 7,793.1, 7,583.2, 7,726.2(cal/g). Heavy metal contens in the oil were under regulatory limit indicating.

• Journal of the Korean Graphic Arts Communication Society
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• v.25 no.1
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• pp.95-107
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• 2007

This study starts to find a way out, experiment and apply commercial UV coatings to the cap closures. The cap closures is made form coating and succeeding deformation process. It is coated with several printing layers, printing and over print varnish coating. Then it pressed in three steps of press called 'deep-drawing'. In this study, two kinds of coating was designed and accomplished in the base of the same manufacturing and environment conditions. Consequently, UV curable ink have adequate performance in this experiment (T-bending, Erichsen Test), but it were experienced several damages in this experiments (web-bending, impact test). They were not cured enough to endure the friction and a unique shape of serial cracks were appeared.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.110-113
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• 2002

As a preliminary study for the three dimensional failure analysis of composite joints, the three dimensional stress analysis on a pin-loaded unidirectional-fabric hybrid composite joints are performed. The contact and frictions between composite plate and metal bush are considered in the finite element method by NASTRAN. Experiments are conducted to validate the accuracy and feasibility of the finite element technique for 25 specimens with 5 different geometries. The finite element and experimental results show the bush cap induces the unsymmetric deformation, stress distribution, and failure behavior through the thickness. The experiment also shows the failure loads are higher in the joint with bush cap than without it.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.652-657
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• 2001

Densification behavior of aluminum alloy(A16061) powder was investigated under cold compaction. Experimental data were obtained under triaxial compression with various loading conditions. A special form of the Cap model was proposed from experimental data of A16061 powder under triaxial compression. The proposed yield function and several yield functions in the literature were implemented into a finite element program (ABAQUS) to compare with experimental data for densification behavior of A16061 powder under cold isostatic pressing and die compaction. The agreement between finite element calculations from the proposed yield function and experimental data is very good under cold isostatic pressing and die compaction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.1
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• pp.95-104
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• 2002

Densification behavior of aluminum alloy(A16061) powder was investigated under cold compaction. Experimental data were obtained under triaxial compression with various loading conditions. A special form of the Cap model was proposed from experimental data of A16061 powder under triaxial compression. The proposed yield function and several yield functions in the literature were implemented into a finite element program (ABAQUS) to compare with experimental data for densifcation behavior of A16061 powder under cold isostatic pressing and die compaction. The agreement between finite element calculations from the proposed yield function and experimental data is very good under cold isostatic pressing and die compaction.

• Current Applied Physics
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• v.18 no.11
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• pp.1388-1392
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• 2018

Metal thin films are used widely to solve the vibration problem. However, damping mechanism is still not clear, which limits the further improvement of the damping properties for film and the development of multi-functional damping coating. In this paper, Damping microscopic mechanism of porous metal films was investigated at both macroscopically and microscopically mixed levels. Molecular dynamics simulation method was used to model and simulate the loading-unloading numerical experiment on the micro-pore and vacancy model to get the stress-strain curve and the microstructure diagram of different defects. And damping factor was calculated by the stress-strain curve. The results show that dislocations and new vacancies appear in the micro-pores when metal film is stretched. The energetic consumption from the motion of dislocation is the main reason for the damping properties of materials. Micro-mechanism of damping properties is discussed with the results of in-situ experiment.

• Journal of Korean Dental Science
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• v.2 no.2
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• pp.53-55
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• 2009

A foreign body may present diagnostic difficulties. If the foreign body has been in existence for a long time, the diagnosis may be even more complex. This report shows an unusual foreign body that turned out to be the cap of a ball point pen.

• Design & Manufacturing
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• v.6 no.1
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• pp.79-83
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• 2012

Anti-theft safety caps for bolted joints are necessary to ensure the safety of citizens and prevent theft of manholes, bridge guardrails, bulletin boards, subway safety handrails and others. Safety caps enhance the look of bolted joints, avert accidents that involve hitting the head of bolts, hamper them from coming loose by covering the head of bolts. This study focuses on press die design methods and press molding condition setting to resolve bursting and cracks in products, and on molding material selection and heat treatment technologies to boost life extension.