• Transactions of Materials Processing
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• v.31 no.6
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• pp.394-403
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• 2022

In the automotive industry, cold-drawn austenitic stainless steel is commonly used to handle high fuel pressures in gasoline direct injection (GDI) engines. In this study, we analyzed the effects of main process variables such as cross-sectional shape, drawing speed and friction coefficient on the microstructure, hardness and residual stress of the drawn material in the two-step cold drawing process. By changing the cross-sectional shape in the first-step cold drawing, the possibility of improving the shape accuracy or physical properties of the finally cold-drawn fuel rail pressure sensor product was investigated.

• Journal of The Korean Association For Science Education
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• v.26 no.4
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• pp.510-517
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• 2006

This study investigated the influences of situational interest, attention, and cognitive effort on drawing as a method to assist students to connect and integrate multiple external representations provided in learning chemical concepts. Seventh graders (N=178) at two coed middle schools were taught about the "Boyle's Law" and the "Charles's Law" for two class hours through drawing. They observed macroscopic phenomena through demonstrations. After these observations, they drew their mental model from the external verbal representation, and then compared their drawings with external visual representation. The tests assessing situational interest, attention, cognitive effort, and conceptual understanding were administered as post-tests. Correlation and path analyses supported a causal model which situational interest had a positive direct effect on attention to the drawing. Attention led to conceptual understanding directly as well as through cognitive effort. These results suggest that situational interest may be induced by drawing first of all, and attention and cognitive effort may be direct causes of conceptual understanding in drawing. Educational implications are discussed.

• Plant Journal
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• v.17 no.3
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• pp.37-41
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• 2021

P&ID((Piping and Instrument Diagram) is a key drawing in the engineering industry because it contains information about the units and instrumentation of the plant. Until now, simple repetitive tasks like listing symbols in P&ID drawings have been done manually, consuming lots of time and manpower. Currently, a deep learning model based on CNN(Convolutional Neural Network) is studied for drawing object detection, but the detection time is about 30 minutes and the accuracy is about 90%, indicating performance that is not sufficient to be implemented in the real word. In this study, the detection of symbols in a drawing is performed using 1-stage object detection algorithms that process both region proposal and detection. Specifically, build the training data using the image labeling tool, and show the results of recognizing the symbol in the drawing which are trained in the deep learning model.

• Journal of The Korean Association For Science Education
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• v.26 no.1
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• pp.9-15
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• 2006

Students have often experienced difficulties in understanding the concept of the particulate nature of matter despite its importance in chemistry. Although various instructional methods have been suggested for teaching this concept, systematic studies have been rarely conducted. Therefore, this study investigated the effects of drawing and analyzing pictures. Three classes of 7th graders at a coed middle school in Seoul were assigned to the control group, the drawing group, and the analyzing group, respectively. Students were taught about the three states of matter and the motion of molecules for 8 class periods. The instructional effects on student conception, achievement, and science learning motivation were investigated by student visual learning styles. Results revealed that the scores of a conceptions test and a science learning motivation test for both the drawing group and the analyzing group were higher than those for the control group. Additionally, the scores of the science learning motivation test were also found to be higher for students with a more visual learning style than their counterparts.

• Journal of The Korean Association For Science Education
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• v.28 no.7
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• pp.724-729
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• 2008

Well-integrated science instruction with art often motivates students to more engage in science learning and to freely express their thoughts and feelings on what they have learned in science classes. This study, therefore, attempted to explore Korean children's imaginary science drawings. Ninety elementary students ($3^{rd}-6^{th}$ graders) in Seoul, South Korea, participated in this study. The guiding research questions were 1) what overall characteristics of students' imaginary science drawings are and how these characteristics represent children's image of science, and 2) what educational value of children's imaginary science drawing activity as a case of science-art integration is. Data sources included a set of children's drawings and individual interviews with selected students. From the drawings, it was found that most of the subjects that children drew tended to be limited to the space. In addition, the children tended to assimilate science into technology that makes our life more convenient. We also found imaginary science drawing can be a good science-art integrated instruction method. Imaginary science drawing has educational benefits; one is a tool to investigate children's thoughts and knowledge of science while the other is method that motivate children to learn science effectively.

• Journal of The Korean Association For Science Education
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• v.35 no.5
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• pp.817-827
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• 2015

This study compared the characteristics and perceptions of science imaginary drawings done by scientifically-gifted and general elementary students. To do this, sixth graders (n=60) at three gifted science education institutes and sixth graders (n=51) at two elementary schools in Gyeonggi province were selected and administered the questionnaires. The analyses of the results indicated that the pictures of scientifically-gifted students included and integrated more academic fields and places than those of general students. The pictures of scientifically-gifted students were also more elaborate, but less painted. In addition, scientifically-gifted students perceived more positively the educational benefits of science imaginary drawing upon cognitive and affective aspects. However, there were no significant differences between scientifically-gifted students and general students in the understanding of science imaginary drawing, distribution of the pictures by times, perceptions on educational benefits of science imaginary drawing upon aesthetic aspects, and perceptions on difficulties in the processes of scientific imaginary drawing. A few scientifically-gifted students answered that science imaginary drawing was not more useful to them than to general students. Educational implications of these findings are discussed.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.97-97
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• 2003

Recently, attention has been paid to biodegradable polymers in relation to the global environment. Poly-lactide (PLA) is one of such polymers and has studied by some investigators. In this study, the changes of crystal structure, crystal orientation and supermolecular structure of Poly(L-lactide) (PLLA) during drawing or annealing have been investigated.

• Transactions of Materials Processing
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• v.24 no.2
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• pp.115-120
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• 2015

Deep drawing of cylindrical cups is one of the most fundamental and important processes in sheet metal forming. Circular cups are widely used in industrial fields such as automobile and electronic appliances. Some of these cups are formed by a one-stage process, others such as battery cases and beverage cans are made by a multi-stage process. In the current study the multi-stage deep drawing of aluminum sheet metal is examined. The process consists of two deep drawing operations followed by two ironing operations. The press die, which can be used for the four-stage forming process, was manufactured allowing punch and die components to be easily changed for various experiments. The rolling direction of both the sheet and the drawn cups was always positioned toward the horizontal x-direction on the die face to minimize experimental errors during the progressive forming. The dimensional accuracy of the cylindrical cups formed at each stage and the earing defect due to the anisotropy of sheet were investigated. The influence of anisotropy on the thickness distribution was also examined. Both the thickness and the outer diameter of the cups were measured and compared for each set of experimental conditions. It was found that the dimensional accuracy of cups rapidly improves by employing the ironing process and also by increasing the amount of ironing.

• International Journal of Industrial Entomology and Biomaterials
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• v.19 no.1
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• pp.181-185
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• 2009

In this paper, the regenerated silk fibroin (SF)/hydroxypropyl methylcellulose (HPMC) blend filaments were prepared by wet spinning and the effect of HPMC concentration on the post drawing and morphology of blend filaments was elucidated. The result of maximum draw ratio indicated that the wet spinnability of wet spun SF / HPMC was improved with increasing HPMC concentration until 8% and remained constant after that concentration. The SEM observation revealed that the enhanced wet spinnability of blend filaments was strongly related to the morphological change by increasing HPMC concentration. Regardless of HPMC concentration, as SF content was reduced, the wet spinnability of blend film decreased resulting in reduced maximum draw ratio. It was also found by SEM observation that the cross section of blend filament deviated from circularity with an increase of HPMC content.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.2
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• pp.49-56
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• 2020

PURPOSE: This study examined the difference in muscle activity of the trunk and legs during flat walking with or without an abdominal drawing-in maneuver. METHODS: This study was conducted on 15 healthy males and eight females who were attending D University in Busan. This experiment was conducted after 15 minutes of abdominal drawing-in training using a pressure biofeedback unit before the experiment, and the difference in the muscle activity of the trunk and legs during flat walking with or without an abdominal drawing-in technique was investigated. Surface electromyography was used, and the electrode attachment site was the right sternocleidomastoid muscle, splenius capitis muscle, rectus abdominis muscle, external abdominal oblique muscle, transverse abdominis muscle, erector spinae muscle, vastus medialis muscle, and vastus lateralis muscle (TM DTS, Noraxon, USA). The data were analyzed statistically using a paired t-test on SPSS version 18.0 (IBM). RESULTS: The muscle activity of the rectus abdominis muscle, external abdominal oblique muscle, transverse abdominis muscle, vastus medialis muscle were increased significantly and maintained more than walking without maintaining an abdominal drawing-in maneuver (p < .05). Moreover, muscle activity of the erector spinae muscle was decreased significantly and maintained more than walking without maintaining an abdominal drawing-in maneuver (p < .05). CONCLUSION: Maintaining an abdominal drawing-in maneuver during flat walking is more effective during walking training.