• The Journal of Korean Physical Therapy
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• v.24 no.1
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• pp.1-6
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• 2012

Purpose: The grip strength is influenced by various factors, such as position of the upper extremity, characteristics of the hand, and general physical condition. In this study, we investigated whether abdominal muscle activity in combination with the abdominal drawing-in maneuver has any effect on the grip strength in healthy young adults. Methods: This study included 31 healthy subjects (16 males, 15 females). We used surface electromyography and pressure bio-feedback unit for this experiment. All Subjects were placed in a cock-lying position with comfort and the grip strength was measured. On the following day, the pressure bio-feedback unit was placed beneath their fifth lumbar vertebra, and the, grip strength was measured again. This time, the measurement was taken while drawing-in their abdomen below the navel gently and gradually, while maintaining a neutral pelvic position. Results: The grip strength was significantly increased when subjects performed the drawing-in maneuver than when they were comfortable (p<0.05). In addition, activations of the rectus abdominal muscles significantly increased (p<0.05). Conclusion: In the current study, we found that abdominal muscle activity, in combination with the abdominal drawing-in maneuver, affected the grip strength, positively. Therefore, we suggest that this result should be considered when evaluating the grip strength.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.1844-1853
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• 1995

Theoretical and experimental drawing characteristics for the single circular and square drawbeads are discussed. During the blank holding process, the strain distributions of upper and lower skins of specimens, and the die reactional forces are analysed by F. E. M., and they are compared with the experimental results. The drawbead restraining forces and strain distributions for the drawn specimens by the various drawing length are also analysed and compared with the experimental results. It is concluded that the theoretical simulations and results could be very useful for the prediction of real cases.

• Transactions of Materials Processing
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• v.11 no.5
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• pp.394-404
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• 2002

The drawbead model for a three-dimensional a finite element analysis of sheet metal forming processes is developed. The mathematical models of the basic drawbeads like circular drawbead, stepped drawbead, and squared drawbaed are first derived using the bending theory, belt-pulley equation, and Coulomb friction law. Next, the experiments for finding the drawing characteristics of the drawbead are performed. Based on mathematical models and drawing test results, expert models of basic drawbeads are then developed employing a linear multiple regression method. For the expert models of combined drawbeads such as the double circular drawbead, double stepped drawbead, circular-and-stepped drawbead, etc., those of the basic drawbeads are summed. Finally, in order to verify the expert models developed, the drawing characteristics calculated by the expert models of the double circular drawbead and circular-and-stepped drawbead are compared with those obtained from the experiments. The predictions by expert models agree well with the measurements by experiments.

• Journal of the Korean Society for Heat Treatment
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• v.18 no.2
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• pp.105-111
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• 2005

In sheet metal forming, drawbeads are often used to control uneven material flow, which may cause defects such as wrinkles, fractures, surface distortion and springback. Appropriate setting and adjusting of the drawbead force is one of the most important parameters in sheet forming process control. Therefore in this study, drawbead test was performed at various bead surface treatment conditions to clarify the frictional characteristics between sheet and drawbead. Furthermore, the differences in drawing force between circular and rectangular shape beads have also been measured to estimate the effectiveness of bead shape on the material flow control. The results show that drawing and friction characteristic were strongly influenced by surface treatments of bead and bead shapes.

• Journal of The Korean Association For Science Education
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• v.34 no.2
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• pp.175-186
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• 2014

This study investigated the influences of pair activity on characteristics of science imaginary pictures drawn by elementary school students and their perceptions of science imaginary drawing. To do this, fourth graders (N=123) from one of the elementary schools were selected and assigned to individual science imaginary drawing (n=61) and paired science imaginary drawing (n=62) groups. The students of each group were administered the questionnaires. The analyses of the results indicated that pair science imaginary drawing was useful in some cognitive aspects (e.g., the understanding of science imaginary drawing, the diversification of topics and times, the generation of scientific ideas, and the elaboration of the pictures) and motivational aspects (e.g., the inducement of interest and intimacy about science, interest about science imaginary drawing, and sociability with friends). However, there were some limitations in positively changing the perceptions of some cognitive aspects (e.g., the acquirement of new scientific knowledge, the remembrance of scientific knowledge, the improvement of the ability to construct scientific logics, and the improvement of scientific imagination) and aesthetic aspects (e.g., the improvement of the abilities to express themes in drawing, paint the picture, and complete the works of art). In addition, the difficulties in imagining, selecting the subject, and expressing could not be overcome; a few disadvantages in the lack of discussion skills were also pointed out.

• Transactions of Materials Processing
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• v.3 no.1
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• pp.51-62
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• 1994

Cup drawing test and U-bending test were performed to evaluate the friction characteristics of sheet materials for the different deformation modes involved in stamping process. The coefficient of friction calculated from the each test was compared to that obtained from the draw bead friction test. It was clarified that the cup drawing test could be simply used for evaluating the friction characteristic of sheet material in deep drawing process with high contacting pressure. However the U-bending test is suitable to evaluate the frictional characteristic of sheet material in bending process with low contacting pressure.

• Journal of Korea Multimedia Society
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• v.9 no.6
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• pp.709-719
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• 2006

To protect against unlawful reproductions and distribution, the current paper proposes a digital watermarking technique for architectural drawings produced using a CAD system. First, the POLYLINEs are extracted from the drawing; then, an adaptive algorithm is used to embed a watermark in the characteristics of each POLYLINE. Next, the CIRCLEs are embedded using an adaptive watermarking algorithm related to the radius of circle from drawing. The proposed watermarking scheme is robust to various attacks, such as the geometrical transformation. Additionally, the proposed method satisfies the requirement of transparency for CAD program. It used AutoCAD 2002, which is commonly used as a CAD program for experiments. Experimental results confirmed the robustness and invisibility of the embedded watermarks in several conversions of an architectural drawing.

• Transactions of Materials Processing
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• v.10 no.5
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• pp.411-417
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• 2001

A Comparative study on deep drawing of clad sheet is carried out to investigate the forming characteristics and the effectiveness of modified finite element analysis. An elasto-plastic finite element analysis Is developed to analyze the forming of clad sheet using explicit scheme and layered shell. Axisymmetric deep drawing of stainless clad metal sheet is performed and thickness distribution is obtained. The corresponding finite element analysis shows good agreement with the results. Some disagreement can be explained by the assumption of shell element and the complexity of deformation of clad sheet.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.306-309
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• 2007

Recently, magnesium alloys have been widely used in automotive, aerospace and electronic industries with the advantages such as lightweightness, high specific strength and stiffness. However, magnesium alloy has quite low formability at room temperature due to its hexagonal close-packed crystal structure. Warm deep drawing is one of the forming technologies to improve the formability of magnesium alloy sheet and the lubrication condition is an important process parameter in that. In this study, the drawing tests of AZ31 alloy sheet at elevated temperature for various kinds of lubricant were carried out and the effects of lubrication conditions on drawbility were investigated.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.05a
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• pp.151-155
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• 2001

The purpose of this study is to investigate the weldline movement of the laser welded sheets during the warm deep drawing process. For this investigation, Five steps of temperature ranges, from room temperature to $200^{\circ}C$, and two kinds of thickness combination, 0.8 mm${\times}$1.2 mm and 0.8 mm${\times}$1.6 mm SCP1 material sheets, were adopted. Also, the numerical analysis using the PAM-STAMP has been carried out with the same models as the specimens. As a result the higher temperature was adopted, the less weld-line movement was observed.