• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.10
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• pp.50-55
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• 2021

In this study, to create circular holes on an inclined conic face, we developed a novel process of vertical piercing on the plane before drawing, instead of applying an expensive cam-piercing method. The pierced holes are deformed during the drawing, and their shapes are affected by the size of the center hole. Using the Abaqus CAE program, the deformation tendency of the holes, according to the diameter of the center hole, was identified, and the diameter for securing the roundness of the side holes were determined through actual experiments. The developed process was successfully applied to mass production of the part, and a cost reduction is expected.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.796-802
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• 2018

In order to remove rust and impurities from surface of raw SUS circular bar, peeling machine is used to make lustrous and clean surface of SUS circular bar. Drawing process system is used to manufacture SUS hexagonal bar. SUS hexagonal bar have been widely used to make hexagonal bolt/nut, adapter and fittings and so on. The purpose of this study is to investigate the stabilities for guide bar of clamp in drawing process system. As the results, the guide bar showed structural stability in cases of below load of 50 Ton and over hook radius of 3.0mm. Further as the thickness of guide bar hooking with jaw was increased, minimum safety factor was decreased.

• Transactions of Materials Processing
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• v.15 no.7 s.88
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• pp.504-511
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• 2006

The drawability of AZ31B magnesium sheet is estimated at various temperatures($200,\;250,\;300,\;350\;and\;400^{\circ}C$), and forming speed(20, 50, 100mm/min), thickness(0.5, 0.8, 1.0, 1.4mm). The deep drawing process of circular cup and square cup were used in forming experiments. Experimental and FEM analysis are performed to investigate drawability and affection of controlled blank holding force. Through the controlled blank holding force, drawability was improved. Limit drawing ratio is increased from 2.1 to 3.0 in circular cup drawing and change of thickness is decreased from 16.3 to 6.9%. This result is verified by FEM analysis. Through the observation of microstructure, the main cause is investigated as a quantity of the dynamic recrystallization.

• Transactions of Materials Processing
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• v.18 no.7
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• pp.550-555
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• 2009

In the multi-pass shape drawing process, the pass schedule that includes the determination of reduction ratio and intermediate die shape is very important. This study used the equal reduction, equal load, and electric field analysis method for pass schedule of the multi-pass shape drawing. The reduction ratio was calculated by the equal reduction and equal load method. And the intermediate die shape was determined by the result of the electric field analysis and the calculated reduction ratio. The proposed pass schedule method was applied to a shape drawing for producing cross roller guide. Finally, FE-analysis and shape drawing experiment were performed to verify the effectiveness of the proposed method.

• Journal of the korean Society of Automotive Engineers
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• v.11 no.4
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• pp.35-42
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• 1989

The major purpose of this paper is a study on the effect of die profile radius on the formability of spring-type blankholder system in deep drawing process. By drawing the various materials, formability is studied by means of checking the drawing force, blankholding force variation, limiting drawing ratio and wall wrinkling phenomenon. As the die profile radius increases, the maximum drawing force and maximum blankholding force decrease regardless of lubrication condition. Because better lubrication induces blankholding force to rise, spring type blankholder system is better to protect flange wrinkling phenomenon than constant pressure type. And wall wrinkling phenomenon was not detected in experimental die radius range, so the Miyakawa's upper wrinkling limit is understimated in case of material tested.

• Journal of Intelligence and Information Systems
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• v.2 no.2
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• pp.55-68
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• 1996

인공 지능의 주요 분야 중 하나의 전문가시스템 기술은 현재 산업현장에서 여러 가지 분야의 문제해결에 이용되고 있다. 본 논문은 축 대칭 원통형 제품의 deep drawing 공정 설계를 위한 전문가시스템 DOX(Deep drawing Opertion eXpert)의 개발에 관한 것이다. 시스템의 입력은 원통형 제품의 형상 정보와 재질 정보이며 자동 인식 또는 수동입력의 방법으로 입력된다. 시스템은 이러한 정보를 받아들여 deep drawing 공정설계에 필요한 다수의 요소들을 결정하며, 최종결과로서 process layout 도면을 CAD 시스템에서 자동 출력한다. 개발된 전문가시스템의 지식베이스는 산업 분야 전문가의 전문 지식과 경험지식을 획득, 분석하여 구성하였으며, 추론 전략으로는 규칙기반추론(rule-based reasoning)을 이용하였다.

• Journal of architectural history
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• v.7 no.3 s.16
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• pp.9-26
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• 1998

Architectural Drawing has been settled down the very effective means of exchanging their architectural ideas and data on the construction process. However, it was not easy to conserve the original drawings, which aims had been accomplished, at the same time, building was built. The same phenomena were occurred in our traditional architectural construction project, especially before pre-modern age. And do not understand soundly building documentation accepted by craftsmen in the period of earliest Chosun dynasty and how to present their idea and information of architectural as means of sketches and drawings. So, this paper aimed to clarify the drawing occurrence and the development steps of their rendering, representation methodology in the construction process in Sannungdogam-Uuigue, which were the construction documents of government based on the royal family's tomb and building projects in the late Chosun Dynasty. There are three development stages of architectural space representation, pre-drawing stage, drawing occurring stage and drawing settlement stage, They had been adapted unique drawing presentation method which were drawn by artisan, so called Doseol(圖說)and Painter Hwawon(畵員) The results are 1. In the Pre-drawing stage, they had been used the systematic explanation method of character 2. Do not have the evidence of adapting drawing before 17th centry, it was originated in early 17's century started with Onga(甕家). Onga's Drawing was drawn very elementary skill, and became development, settlement and standardization of their drawing representation around 19th century 3. The drawing presented by client's recognition view of space and building, integrated data within a sheet of drawing with practical and hierarchy and using graphic and description.

• Korean Journal of Computational Design and Engineering
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• v.5 no.3
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• pp.255-262
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• 2000

A computer-aided process planning (CAPP) system for rotationally symmetric deep drawing products has been developed. The application for non-axisymmetric components, however, has not been reported yet. Therefore, this study investigates process sequence design in deep drawing process and constructs an expert system of process planning for non-axisymmetric motor frame products with elliptical shape. The system developed consists of four modules. The first one is recognition of shape module to recognize the products. The second one is a 3-D modeling module to calculate surface area for non-axisymmetric products. The third one is a blank design module that creates an oval-shaped blank with the identical surface area. The forth one is a process planning module based on production rules that play the best important role in an expert system for manufacturing. The production rules are generated and upgraded by interviewing with field engineers. The constructed system using AutoLISP language under the AutoCAD environment is baled on the knowledge base system which is involved a lot of expert's technology. Results of this system will be provide effective aids to the designer and engineer in this field.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.2
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• pp.77-81
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• 2017

CP (Commercially Pure) titanium has been widely used in various industries such as in energy plants and bio-materials because of an excellent corrosion resistance and its non-toxicity to the human body. But there are limitations for usage as structural materials due to low strength. The tensile properties of CP titanium could be improved by microstructure refinement such as in a SPD (Severe Plastic Deformation) process. However, high strengthening of CP titanium wire is impossible by SPD processes like ECAP (Equal Channel Angular Pressing), HPT (High-Pressure Torsion), and the ARB (Accumulative Roll Bonding) process. The study purposes are to increase the strength of CP titanium wire by optimization of the cold drawing process and the harmonization with mechanical properties by heat treatments for the next forming process. The optimization process was investigated with regard to the design of drawing dies and the reduction ratio of cross sections. The elongations of high strength CP titanium were controlled by heat treatment.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.1
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• pp.5-14
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• 2007

It is necessary for development of drawing product with press to have suitable material selection & all process design and the problem during press process has been cleared from judgement of experience & trial and error. Recently we can estimate press process result from computer aided design & FEM. But we can get more reliable result when we can put more precise process variants during FEM. In case of using a drawbead that is used for the material inflow, it is considered for us to put material property, other analysis condition & friction figure when material is passing through the drawbead for better FEM. From our study, we have drawn an analogy bead connection depth, friction figure & drawing and restraining load according to kinds of lubrication from experiment & FEM for the drawbead. We applied above result to the drawing experiment & FEM and confirmed the validity. We could notice the relation between friction figure & drawing load and the friction figure variation according to kinds of lubrication. It is expected to draw more precise analogy that can be used for real process due to more precise process variants application to FEM.