• Tribology and Lubricants
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• 제38권4호
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• pp.128-135
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• 2022

In the product development process, the reliability of the product can be secured through durability tests. However, since the durability test method is expensive and time consuming, a method to save time and money by utilizing virtual product development (VPD) is required. However, research on the accuracy of the results of virtual product development is required. In this paper, an accelerated durability test was designed and conducted using a planetary gear decelerator. And an analysis model under the same conditions was created and simulated. To correlate the results of the experiment with the results of the analytical model, created a model that can discriminate the wear region using one of the data mining methods, the k-means algorithm method and HSV (Hue, Saturation, Value). The wear area is compared by counting the number of pixels defined as wear through a discrimination model. A similar ratio was calculated by comparing the pixel ratio of the area determined as wear in the entire area. It showed a similar ratio of about 70%, and it is necessary to improve the discrimination method.

• 한국의류산업학회지
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• 제13권4호
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• pp.624-634
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• 2011

The purpose of this study is to develop the pattern of safety clothes used at flat or mountainous areas and to identify the pattern of safety clothes by conducting experimental evaluation of virtual wear. Three subjects were selected, based on fire fighters' physical constitution. A prototype design for safety clothing was determined after in-depth interviewing of professionals and surveying of Forest service staff and related agency. Wearing test should be carried out in the order of pattern making, virtual and real wearing evaluation. For data analysis, technical statistical values should be obtained by using body measurements of subject, frequency analysis and T-test. The jacket is designed to have a front extension and the entire length of clothing enough for wearer to put on it over ordinary shirts or sweater. The collar of jacket is of round type. Cyber reality enables to identify the movement and activity of virtual fitting model and to find out errors or problems in safety clothing prior to on-the-spot wear test, thus raising the precision level of pattern. There was significant difference between real and virtual fit preference. The results show that the virtual try-on system need the development of a specific style.

• 한국의상디자인학회지
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• 제16권3호
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• pp.1-13
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• 2014

This study investigated body type among women in their 20s and the development of prototypes for tailored jackets by body type in order to design clothes in consideration of an imbalance in body type caused by the popularity of portable devices such as smartphones and Netbooks. This study aims to create a design of jacket patterns by body type through both actual and virtual wear testing among women in their 20s, who are the major consumer of ready-made clothes and are very sensitive to size fit. This study will provide pattern information for the manufacture of jackets with a goal of securing the latest scientific body type information and establish the grounds for a research method in the manufacture of clothes. According to actual and virtual wear tests of four different body types, a significant difference was found in armhole circumference in most types because it was scanned with the arms slightly apart to prevent the armhole area from being missed during the 3D scanning. This has resulted in a slight distortion in measurements. To correct this problem, it is necessary to verify the precision of the body scanner and its program. In categories in which a large significant difference was found, it is necessary to test them against many subjects. In addition, it would be required to perform a further study on the 3D virtual wear system, which could be useful in the clothing industry.

• Journal of Periodontal and Implant Science
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• 제48권2호
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• pp.124-134
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• 2018

Purpose: Clinicians must examine tooth wear to make a proper diagnosis. However, qualitative methosds of measuring tooth wear have many disadvantages. Therefore, this study aimed to develop and evaluate quantitative parameters using the cusp area and volume of virtual dental models. Methods: The subjects of this study were the same virtual models that were used in our former study. The same age group classification and new tooth wear index (NTWI) scoring system were also reused. A virtual occlusal plane was generated with the highest cusp points and lowered vertically from 0.2 to 0.8 mm to create offset planes. The area and volume of each cusp was then measured and added together. In addition to the former analysis, the differential features of each cusp were analyzed. Results: The scores of the new parameters differentiated the age and NTWI groups better than those analyzed in the former study. The Spearman ${\rho}$ coefficients between the total area and the area of each cusp also showed higher scores at the levels of 0.6 mm (0.6A) and 0.8A. The mesiolingual cusp (MLC) showed a statistically significant difference (P<0.01) from the other cusps in the paired t-test. Additionally, the MLC exhibited the highest percentage of change at 0.6A in some age and NTWI groups. Regarding the age groups, the MLC showed the highest score in groups 1 and 2. For the NTWI groups, the MLC was not significantly different in groups 3 and 4. These results support the proposal that the lingual cusp exhibits rapid wear because it serves as a functional cusp. Conclusions: Although this study has limitations due to its cross-sectional nature, it suggests better quantitative parameters and analytical tools for the characteristics of cusp wear.

• 한국지역사회생활과학회지
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• 제28권4호
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• pp.505-514
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• 2017

Although studies on the development of cool touch fabrics have been conducted widely, the effects of fitted pattern on enhancing the cooling sensation are insufficient. To investigate the effect of cool-touch fabric and fit of women's sports underwear, 3D and 2D patterns of sleeveless top and sports leggings were constructed. The performance of cool touch was tested by the Qmax value and wear test with nine subjects. Objective fit evaluation was observed by 3D virtual clothing using Clo software. Subjects rated wearing sensation such as 'cooling sensation, fit, wear comfort and preferences of purchase' using Likert's scale in the environmental chamber at $25^{\circ}C$, 45 %RH. The Qmax value of the cool touch fabric was higher than that of the PET fabric, which was well reflected in 'cooling sensation', especially in the case of a tight-fitted 3D pattern. The cooling sensation of the cool-touch fabric was not significantly elevated with 3D tight pattern as long as the size of the 2D pattern was similar to that of 3D pattern. However, the purchase preference was highly correlated with 3D fit and wear comfort.

• 대한치과기공학회지
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• 제38권3호
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• pp.217-224
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• 2016

Purpose: This study aimed to generate 3-D occlusal curvatures and evaluate the relationship between the occlusal curvatures and mandibular occlusal morphology factors. Methods: Mandibular dental casts from 25 young adult Korean were scanned as a virtual dental models with a 3-D scanner(Scanner S600, Zirkonzahn, Italy). The curve of Spee, curve of Wilson, and Monson's sphere were generated by fitting a circle/sphere to the cusp tips using a least-squares method. The mandibular mesiodistal cusp inclination, buccolingual cusp inclination, and tooth wear parameters were measured on the prepared virtual models using RapidForm2004(INUS technology INC, Seoul, Korea). Wilcoxon signed-rank test was performed to test side difference, and Spearman's rank correlation coefficients were investigated to verify the correlation between occlusal curvatures and correlated factors (a=0.05). Results: The mean radii of curve of Spee were $83.09{\pm}33.94$ in the left side and $79.00{\pm}28.12mm$ in the right side. The mean radii of curve of Wilson were $66.82{\pm}15.87mm$ in the mesial side and $47.87{\pm}9.40mm$ in the distal side with significantly difference between mesiodistal sides(p<0.001). The mean radius of Monson's sphere was $121.85{\pm}47.11mm$. Most of the cusp inclination parameters showed negative correlation for the radius of Monson' sphere(p<0.05). Especially, the buccolingual cusp inclinations in mesial side of molar showed high correlation coefficients among the factors(p<0.05). Conclusion: The radius of Monson's sphere was greater than the classical 4-inch values, and the buccolingual cusp inclinations in mesial side of molar can be considered as one of the main factors correlating with the radius of Monson's sphere.

• 한국생활과학회지
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• 제21권2호
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• pp.299-314
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• 2012

The purpose of this study was to explore effects of pattern alteration using a virtual clothing simulation approach in combination with 3D analysis software. Three raglan sleeves of different patterns were worn by an avatar using virtual clothing simulation with silk and cotton as the test fabrics. It was observed that the silhouette and hemline shape were affected differently based on raglan sleeve pattern and fabric type. By examining clothing pressure distribution, the cotton fabric designs and pattern shapes provided for a variety of influences on armhole and bust regions as well as the back sleeve area. For representative locations, cross section circumstance, cross section area, and volume were measured by using 3D analysis and the resulting correlation between the 2D and 3D data were investigated. Among different fabrics, there was little difference between the 2D and 3D clothing surface area. However, when using 3D analysis, clothing volume was significantly affected by different fabrics and pattern types. By simultaneously adopting the virtual simulator and 3D analysis, quantitative assessment of virtual clothing simulation was successfully conducted. In light of the results of this study, the resulting methodology is expected to be used as a comprehensive evaluation tool for virtual clothing simulation wear testing.

• 복식문화연구
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• 제25권4호
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• pp.476-487
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• 2017

The purpose of this study was to suggest torso patterns that fit the three main body shapes of elderly obese women. To reduce time, costs, and also the trial and error needed to make patterns, the CLO program for 3D test wear was employed. Three virtual models for aged obese women were use, with the YUKA system used to produce torso patterns. 3D simulation of test wear and corrections was done to design optimal torso patterns. The results were as follows: First, for the three models of obese women's body shapes as realized by CLO 3D, Type 1 is lower-body obesity shapes, Type 2 is abdominal obesity shapes, and Type 3 is whole-body obesity shapes. Second, to design the study patterns, actual measurement values, back waist length and waist to hip length, were used. The armhole depth (B/4-1.5), front interscye (B/6+2.3), front neck width (B/12-0.5), front neck depth (B/12+0.5), front waist measurement (W/4+ 1.5+D), front hip measurement (H/4+2+0.5), and back hip measurement (H/4+3-0.5) were calculated using formulas. Third, according to the results of test-wearing the study patterns, reduced front neck width and depth improved the neck fit and reduced armhole depth bettered loose or plunging armhole girth and also reduced the sagging of bust c.. Also, tight sidesfrom aprotruded waist and abdomen improved with the increase of surpluses in the back waist and also back and front hip c. The exterior was enhanced by displacement of back and front darts, which distributed surpluses better.

• 융합정보논문지
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• 제8권1호
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• pp.131-138
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• 2018

본 연구는 완전 몰입형 가상현실 장비의 사용으로 발생하는 사이버 멀미로 인해 야기된 동적균형의 변화가 낙상을 일으키는지 알아보고자 하였다. 연구의 취지를 이해하고 자발적으로 참여에 동의한 균형감각이 정상인 20대 성인남녀 39명을 대상으로 VR착용 전과 후의 멀미지수, 심박수를 측정하고 Biorescue의 안정성 한계 검사를 실시하였다. 가상현실 체험을 위한 도구로 Samsung gear VR을 이용하였고, To the Homeland 라는 게임을 20분간 실시하였다. VR착용 후 동적균형훈련이 약간 감소하였으나 통계적으로 유의한 차이는 없었다. VR착용 전과 후의 멀미변화는 멀미설문조사를 통해 통계적으로 유의한 차이가 있음을 알 수 있었다. 심박수 변화는 Pulse Oximeter을 이용하여 심박수 증가를 보여 통계적으로 유의한 차이가 있었다. 일반인을 대상으로 완전 몰입형 가상현실 체험은 멀미가 유발되나 동적균형문제에는 다소 영향을 미치지 못하였다. 그렇기 때문에 VR 착용으로 인한 사이버멀미는 균형감소와 낙상을 유발시키지 않는다.

• 한국의류학회지
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• 제32권1호
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• pp.99-109
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• 2008

The purpose of this study was to survey sizing system and preferable ease and to decide the body measuring items for pattern making in a men's dress shirt for mass customization industry that is rising to the surface as a new production system. For this, it had a survey subjects were 254 males between 25 to 44 years old who wear dress shirt frequently and the relevant on line companies, and analyzed the garment sizing system and preferable ease. Collected data were analysed by frequency analysis, t-test, $X^2-test$, and ANOVA using SPSS 12.0 for window. Garment pattern making should reflect the sizes of the body parts well, and simplification of the ordering process would work as an important variable. In relation to the preferable ease, older people preferred more ease while younger people preferred fit ease. In relation to the sizes, people wearing the size of '110' preferred more ease than the size of '90'. And people weighing over 90kg preferred sufficient ease than less weighing. People height over 170cm people preferred sufficient ease for the length between shoulders than height under 170cm. In case of the companies had no consistent sizing system. Significant difference was found in the sizes, except for the size of '100', among those companies, there was significant difference in the length between shoulders and the length of the shirt among those companies and those sizes. Significant body parts for a garment pattern making was height, the circumference of the neck, the chest circumference, the length between biacromion, the arms length, and the waist circumference.