• Transactions of Materials Processing
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• v.31 no.5
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• pp.281-289
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• 2022

Presently, 3D printers manufactured by material extrusion are economical and easy to use, so they are being used in various fields. However, this study conducted a tensile test on the infill pattern and density of the PLA+ material, due to the limitations of long printing time as well as low mechanical strength. The infill area for the infill density change was measured, using a vision-measuring machine for four infill patterns (concentric, zigzag, honeycomb, and cross) in which the nozzle path was the same for each layer. The tensile strength/weight[MPa/g] and tensile strength/printing time[MPa/min] of the tensile specimens were analyzed. In this study, efficient infill density and patterns are suggested, for cost reduction and productivity improvement. Consequently, it was confirmed that the infill area and infill percentage of the four patterns, were not constant according to the infill pattern. And the tensile strength of the infill density 40% of the honeycomb pattern and infill density 20% of the cross pattern, tended to highly consider the weight and printing time. Honeycomb and cross patterns could reduce the weight of the tensile specimen by 19.11%, 28.07%, as well as the printing time by 29.56%, 52.25%. Tensile strength was high in the order of concentric, zigzag, honeycomb, and cross patterns, considering the weight and printing time.

• Transactions of Materials Processing
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• v.31 no.2
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• pp.89-95
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• 2022

3D printing products manufactured by material extrusion are used in many industrial fields recently. However, these products are difficult to use in the field due to their low tensile strengths. In order to solve this problem, research on improving the tensile strength of the output using a 3D printer has been continuously conducted. In this study, we performed a tensile test using Universal Testing Machine according to infill pattern, nozzle temperature, bed temperature, and printing speed conditions. Results revealed that tensile specimen of concentric shape had the highest tensile strength in infill pattern condition and that the tensile strength increased linearly with increasing nozzle and bed temperatures. However, the tensile strength decreased with increasing printing speed. Consequently, we confirmed that tensile strength could be increased and decreased depending on output conditions of 3D printing.

• Transactions of Materials Processing
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• v.32 no.5
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• pp.255-267
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• 2023

Recently, 3D printing using a material extrusion method is used in various fields. Since plastic material has lower strength than steel, research to increase the strength is continuously being conducted. This study investigates the lattice structure for additive manufacturing of six 3D infill patterns (octet, quarter cubic, cubic, cubic subdivision, triangles and cross 3D) which consist of tetragons, hexagonal trusses, equilateral triangles and cross shapes. Consequently, in the tensile strength considering the weight and printing time, octet, quarter cubic, cubic and triangles patterns tended to increase linearly as the infill density increased, except for the infill density of 20%. However, the tensile strength/weight performed better than the infill density of 100% when the cubic subdivision pattern had the infill density of 20% and the cross 3D pattern had the infill density of 40%. Considering the weight and printing time, the infill patterns of high tensile strength were octet, quarter cubic, cubic, cubic subdivision, triangles and cross 3D order.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.170-175
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• 1999

Noncontact measuring methodology of 3-dimensional profile using CCD camera are very attractive because of it's high measuring speed and its's high sensitivity. Especially, when projecting a grid pattern over the object the captured image have 3 dimensional information of the object. Projection moire extract 3-D information with another grid pattern in front of CCD camera. However phase measuring profilometry(PMP) obtain similar results without additional grid pattern. In this paper, new method for grid pattern generation system by polygonal mirror and Laser Diode. This system is applied the projection moire and the PMP.

• The Research Journal of the Costume Culture
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• v.31 no.5
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• pp.627-639
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• 2023

This study seeks to increase the satisfaction of elderly men when purchasing and wearing ready-to-wear clothes by designing a slacks pattern suitable for their body type, which is determined by analyzing their lower bodies using virtual avatars and 3D virtual simulation system. The study found the following. First, based on virtual visualization of the comparison slacks pattern, the waistline position was consistently the lowest scored question among the evaluation survey items. Interpretation of this dissatisfaction suggests that, because the front waistline falls below the abdomen, the lower body, and especially the abdominal shape, is unpleasantly emphasized. Second, by using a virtual simulation system, the study developed a new slacks pattern that considered the concerns of elderly men. The primary measurement changes were as follows: front waist girth W/4+1.5cm+0.5cm, back waist girth W/4+1.5cm-0.5cm, front hip girth H/4+2.5cm-0.5cm, back hip girth H/4+2.5cm+0.5cm. Third, the new slacks pattern's appearance was evaluated more highly than the comparison pattern, confirming the new pattern's appropriateness for elderly men. This study demonstrates how slacks and other clothing patterns designed in a 3D virtual garment simulator can be used to design more appealing clothing for elderly men, increasing the satisfaction of wearing ready-made clothes at older ages.

• Korean Journal of Human Ecology
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• v.17 no.3
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• pp.469-483
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• 2008

Body image is important as it is related to self-esteem and can be enhanced by clothing and the degree of enhancement is related to clothing fit. The purpose of the paper is to find the adequate ease distribution of jacket pattern for the obese women who want to slenderize their shape by optical illusion. Subjective evaluation of the visual appearance we collected and, at the same time, 3D clothing air volume was observed for the nine types of experimental jackets with different ease distribution. As results it was found that jacket pattern for the obese women is that the front width of pattern is wider than what of back width in waist and abdomen. It was also noted that there was distance between clothing and skin in the girth around hip of jacket. 3D scanner clearly demonstrated the distribution of ease is useful to find the pattern variables responsible for the slender appearance of the obese women. The ready-to-made clothes for the obese women's clothing should be manufactured systematically in due consideration of the diversity and scarcity of the obese women's body shape.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.10
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• pp.770-779
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• 2014

In this study, a numerical estimation method for 3D underwater radiated noise pattern using hull vibration and total acoustic power of the vibrating structure in the far-field is proposed. The underwater radiated noise pattern is known to be predicted using the vibration signals and radiation efficiency of each surface patch. But it is very difficult to know radiation efficiency of each surface patch which is one of important factors to calculate the 3D underwater radiated noise pattern. Instead of using radiation efficiency of each patch, the underwater radiated noise level is modified with the total acoustic power of the vibrating structure. The suggested estimation method for underwater radiated noise pattern is discussed with numerical model.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.1
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• pp.139-148
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• 2009

In this study, we tried to verify the effectiveness of 3D scans of clothed participants from 20 to 24 year old men in fit analysis process. Carrying out fit analysis, we used 3D scan data and direct fit evaluation with the basic garments made as semi-fitted bodice pattern for men. The result of fit evaluation through 3D scan data showed the expert rated fitting items more positive than direct fit evaluation. Even though, generally there was a no significant difference in the response between 3D and direct fit analysis. Only there was a significant difference in the response to the specific place such as the center front line, neckline, shoulder seam, and etc. There was a no significant difference between the result of 3D scan and direct fit evaluation in the subjects' group. Also the result of assessment of 3D targeting consumers showed very positive and interested in using 3D scans for fit analysis. The ability to rotate the 3D scans for a variety of views proved to be a very effective process to analyze fit. Moreover, digital data is easily accessed at any locations and any time. Fit analysis using 3D scans could be great tool for not only fit evaluation in research but also better fitting in apparel industry.

• Journal of Information Display
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• v.11 no.4
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• pp.140-143
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• 2010

A simple and versatile method of fabricating color patterns in two-dimension (2D) and three-dimension (3D) was developed using the selective-wettability approach. Red, green, and blue color elements are sequentially formed on a single substrate in a pattern-by-pattern and/or pattern-on-pattern fashion, through a simple coating process. Either 2D or 3D structures in an array format are produced by controlling the thickness of the hydrophobic layer (HL) coating a substrate within the framework of wetting transition. Moreover, it was demonstrated that the stacked geometry of two successive patterns can be easily tailored for various types of color arrays, with the pattern fidelity of a few tens of nanometers in terms of only a parameter of the HL thickness.

• Journal of the Korean Society of Costume
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• v.50 no.2
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• pp.97-109
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• 2000

The purpose of this study is to apply 3D computer graphics in fashion design as a creative medium and it attempts to fine out what advantages 3D technique can offer to fashion design. For this purpose, this study, first, tries to develop a 3D digital model in which designer can select design, color , pattern and fabric palette whatever necessary . This study uses of the software named 'Poser of Fractal Design' and the and the 3D digital model comprises four stages ; body modeling, item design (item coordination), color design (color coordination), pattern and fabric design (pattern and fabric coordination). Secondly, this study seeks to accumulate a data base which was produced in the course of case studies, which have applied 3D digital model to design. The outcome of the case studies shows that 3D digital model can enhance designing in the following four aspects. ⅰ) It can give more freedom to designer to try various ideas, revise and modify them, It can also produce random generation. Through this process, the designer test various input and output without damage on fabric after revision and alteration. ⅱ) It can help designers to enhance their accuracy. Since fault in the design developed by the 3D digital model can be detected in advance, designers can make correlation before actual work begins. In the end, designers can express their ideas and intention accurately as well as freely. ⅲ) Since design developed by the 3D digital model can be shared on screen by various actors in the course of priduction such designers , merchandisers, and supervisors, it can help communication between and cut the time of feedback.ⅳ) By using the 3D digital model, designers can work from the begining with awareness of actual outcome their design, since the 3D digital model provide animation, which helps designers to envisage visual changes as they apply various items, colors, pattern and fabrics.