• Proceedings of the KSME Conference
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• 2001.06c
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• pp.616-620
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• 2001

The wrinkling in the flange and wall of a part is a predominent failure mode in stamping of sheet metal parts. In many cases this wrinkling may be eliminated by appropriate control of the blank holding force(BHF), but BHF affects the draw depth. Although the wrinkles of flange have been made in the incipient stage of drawing, if the height of wrinkles is maintained under a prescribed limit by decrease or extinction of wrinkles in the course of drawing, small BHP can be allowed so that the depth of drawing could be increased. Authors research the variation of the wrinkles in flange in the course of square cup drawing by using aluminium A1015 and aluminium alloy A5052.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.6
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• pp.90-100
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• 1991

This paper represents the analysis of the sheet drawing by applying the Matrix method to Hill's slip-line field for small reduction and indirect type slip-line field in case of large reduction. Results of the analysis represent the relation between the reduction ratio and the die wall pressure, mean drawing stress through rough die. The limitation on the use of this slip-line field is described. When the reduction ratio is given, the optimum die angle is analyzed in this paper.

• Korean Journal of Computational Design and Engineering
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• v.13 no.4
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• pp.286-295
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• 2008

Construction industry, which is a composite industry being performed by organic combination of various tasks, gives birth to a various of information in the stages of planning, designing, and maintenance management. In particular, the drawing information is broad in the scope of use because it contains all information about buildings as wall as bid, materials, contracts. Therefore, the management of drawing information security is one of the most important factors, which determines the success of failure of business. The major findings and result of this study are as follows to control the distributed drawing information in the collaboration environment. 1) Analysis for function and practical use of DRM in the construction industry. 2) Proposal for applications of DRM that can secure IFC model-based drawing information in the collaboration environment. 3) Extraction from additional IFC entities to apply DRM to part 21 physical files 4) Analysis for functions which are necessary in DRM application prototype system and development of the system. 5) Development IFC model-based DRM prototype system.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.406-411
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• 2003

It is clearly demonstrated that deeper cups could be formed by single and double stretch-drawings from smaller circular blanks due to such wall-thinning action than in the usual deep-drawing of larger blanks. From this fact, it is emphasized that the deep-drawability of a sheet metal Is not evaluated simply by the conventional L.D.R (limiting drawing ratio), but the depth of the drawn cup should also be taken into account. Many experimental data about various metals and thicknesses given in this paper offer a valuable information in this process for more general use which recommends to replace the conventional deep-drawing process by the stretch-drawing process both for single and double operations. In the single stretch-drawing, it is also confirmed that a deeper cup can be produced by raising the blank-holding force at later stage of operation.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.592-599
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• 2009

In this paper, I explain the design and implementation of an automated drawing system by communicating with a user. I made a system providing an UI for virtual environmental actual robot to interwork with environment to make a drawing that I was able to read work, and to help convenience of a user in computers. The UI of a system was used the AWT(Abstract Window Toolkit) in NetBean tools. To draw images, I got image information from SVG vector files. This system can make images according to the demand of users by using real-time communication. Also this kind of drawing process can be an artists performance, not only the final image as a result of the work. So I suggest that this real-time drawing process which is operated by user’s command can be considered as an artists performance.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.42-45
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• 1997

Weldline movement of tailored blanks originates from two sources, primary and secondary. Primary movement occurs by geometrical reason, that is, just scratched lines on the no-weld blanks move during drawing to be fitted to geometrical change. Secondary movement is induced by the characteristics of tailored blanks itself. The primary movement was mainly dependent on the weldline location and not affected by the type of material. The secondary movement caused by laser welding and/or small strength difference in this study was not dominant compared with primary movement. The formability of tailored blanks always inferior to those of original blanks. This is due to the existence of hardened weld bead. The closer a weldline is to punch corner where drawing is most active, the worse its formability becomes. This is because the weldline prohibits the drawing process. It was confirmed by measuring diagonal length at the blank corner. The mode of fracture was changed form wall break to draw break when the weldling was close to the punch corner.

• Transactions of Materials Processing
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• v.8 no.3
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• pp.262-268
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• 1999

This paper reviews the rules for optimizing die design and the process variables such as die shoulder radius and punch to die clearance, which are important factors in drawing the sheet metal without failures during deep drawing. To find the optimum conditions for improving deep drawability, a series of the experiments are performed, and the wall thinning and thickening variations are investigated in each process of deep drawing for a complex cylindrical shell. From the results of this proposed experiment, the optimum values of process variables are examined and discussed, and the usefulness of the present suggestion is shown.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.845-848
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• 2002

The wrinkling in the flange and wall of a part is a predominent failure mode in stamping of sheet metal parts. In many cases this wrinkling may be eliminated by appropriate control of the blank holding forco(BHF), but BHF affects the draw depth. Gotoh had studied the wrinkles under 0.02mm in height. In general, the height of wrinkles could be limited under 0.2mm practically. Therefore small BHP can be allowed so that the depth of drawing could be increased. Authors research the variation of the wrinkles in flange in the course of cup drawing by using aluminium alloy Al050 and A5052.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.22 no.1
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• pp.9-15
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• 2016

Background: This study was conducted to investigate the effects of unstable modified wall squat exercises accompanied by abdominal drawing-in on the gait variables of healthy adults. Methods: The total number of subjects was 30, and 15 were randomly placed in the training group (TG) and 15 in the control group (CG). To determine the gait variables of TG and CG, step length difference (SLD) stance phase difference (STPD), swing phase difference (SWPD), single support difference (SSD), and step time difference (STD) were measured using OptoGait, a gait analysis system. Results: When the pre-intervention and post-intervention results of TG and CG were compared, statistically significant differences in SLD, STPD, SWPD, SSD and STD of TG were seen. Conclusion: Unstable modified wall squat exercises accompanied by abdominal drawing-in might help reduce the deviation between left and right gait variables during walking.

• Transactions of Materials Processing
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• v.15 no.2 s.83
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• pp.148-152
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• 2006

In this study, the experiments of warm deep drawing were done with heated die, and with heated die, and blankholder, and cooled punch in order to investigate the formability of AZ31 magnesium alloy sheet in warm deep drawing. For this, warm deep drawing experiments were executed under various temperatures and punch velocities. The results of warm deep drawing with heated die showed that fracture occurred around the punch part at punch velocity of 75mm/min and punch stroke of 10mm under temperature range of 373-523K, but did not occur under temperature range of 548-673K even punch stroke of 25mm. And fracture at the punch stroke of 25mm and the temperature of 523K did not occur under the punch velocity of 30mm/min, but occurred under punch velocity of 75 and 125mm/min. Also warm deep drawing with heated die and blankholder, and cooled punch showed that the temperature range happening maximum height under punch velocity of 10-100mm/min was around 498-523K. Finally, with heating and cooling technique necking of AZ31 magnesium alloy occurred at punch shoulder part under the temperature range of 293-423K, but at die wall part under the temperature range of 473-573K.