• The Journal of Advanced Prosthodontics
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• v.13 no.3
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• pp.144-151
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• 2021

PURPOSE. The purpose of this in vitro study was to investigate the wear resistance and surface roughness of three interim resin materials, which were subjected to chewing simulation. MATERIALS AND METHODS. Three interim resin materials were evaluated: (1) three-dimensional (3D) printed (digital light processing type), (2) computer-aided design and computer-aided manufacturing (CAD/CAM) milled, and (3) conventional polymethyl methacrylate interim resin materials. A total of 48 substrate specimens were prepared. The specimens were divided into two subgroups and subjected to 30,000 or 60,000 cycles of chewing simulation (n = 8). The wear volume loss and surface roughness of the materials were compared. Statistical analysis was performed using one-way analysis of variance and Tukey's post-hoc test (α=.05). RESULTS. The mean ± standard deviation values of wear volume loss (in mm³) against the metal abrader after 60,000 cycles were 0.10 ± 0.01 for the 3D printed resin, 0.21 ± 0.02 for the milled resin, and 0.44 ± 0.01 for the conventional resin. Statistically significant differences among volume losses were found in the order of 3D printed, milled, and conventional interim materials (P<.001). After 60,000 cycles of simulated chewing, the mean surface roughness (Ra; ㎛) values for 3D printed, milled, and conventional materials were 0.59 ± 0.06, 1.27 ± 0.49, and 1.64 ± 0.44, respectively. A significant difference was found in the Ra value between 3D printed and conventional materials (P=.01). CONCLUSION. The interim restorative materials for additive and subtractive manufacturing digital technologies exhibited less wear volume loss than the conventional interim resin. The 3D printed interim restorative material showed a smoother surface than the conventional interim material after simulated chewing.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.501-508
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• 2019

Today, home gardening is in the spotlight. Therefore, the necessity of developing a new type of gardening product was raised according to the consumer's desires. This study, the contents were developed using sparrows, a helper who helped the bean rat's grain-cracking task among the characters of 'kongjwi patjwi'. The cultural contents convergence product is a lid production that is used at the end of the plant support. The fabrication method was designed using UG NX program after design research, and after printing by 3D polyjet method, mold was made and cast into silicon and resin. Through product manufacturing, we could confirm the public's interest in the possibility of new products and creativity. In the future, it is expected that the development of products incorporating cultural contents through various cultural archetypes will be activated, contributing to the enhancement of economic added value and national brand value.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.1-10
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• 2020

This paper reviews the recent development of electronic textile technology, mainly focusing on chip-textile bonding. Before the chip-textile bonding, a circuit on the textile should be prepared to supply the electrical power and signal to the chip mounted on the fabrics. Either embroidery with conductive yarn or screen-printing with the conductive paste can be applied to implement the circuit on the fabrics depending on the circuit density and resolution. Next, chip-textile bonding can be performed. There are two choices for chip-textile bonding: fixed connection methods such as soldering, ACF/NCA, embroidery, crimping, and secondly removable connection methods like a hook, magnet, zipper. Following the chip-textile bonding process, the chip on the textile is generally encapsulated using PDMS to ensure reliability like water-proof.

• Fashion & Textile Research Journal
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• v.23 no.6
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• pp.810-825
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• 2021

This study measured and analyzed clothing pressure at each measurement part of commercial body shapers to provide basic information for product design and clothing pressure standard and level. This study used five body shaper. Clothing pressure measurements were taken at 18points: Anterior area 8points, lateral area 5points, posterior area 5points. The findings of this study were as follows. As a result of measuring the clothing pressure, the body shaper 1 showed the highest pressure, and body shaper 5 showed the lowest pressure at almost of the measurement points of the three body types. In some cases, body shapers 2, 3, and 4 showed different orders of pressure depending on the measurement point. The highest measured values in most body shapers were the P1 shoulder area and the P2 bust area. The lowest measurement area differed by body type, but mainly P3 underbust area, P4 thorax area and P9 axillary area, P11 waist lateral area, P13 hip lateral area. These body shapers showed different results depending on the the manufacturers and body type of middle-aged women, and because there was no standard for the pressure value. Therefore, it is necessary to design a body shaper sizing system after accurately setting the clothing pressure value for each body part of the consumer.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.3
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• pp.158-167
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• 2023

As digital technology has advanced in the field of dentistry, the use of computer-aided design/computer-aided manufacturing (CAD/CAM) has brought changes to the stages of dental treatment. The use of CAD/CAM technology in dental restoration offers clinical efficiency and convenience by reducing production time and appointment intervals, while also simplifying the fabrication process to reduce errors. In this case, digital replication and printing of temporary teeth were used to aid a patient with complex medical histories and physical disabilities. The final impression obtained with silicone impression material included information on the vertical dimension, centric relation, and the angle and length of the anterior teeth, which shortened the production time and appointment intervals and increased patient satisfaction. The final restoration was fabricated using milling and monolithic disc techniques, demonstrating appropriate stability, retention, and support, resulting in functional and aesthetic satisfaction.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.1
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• pp.73-86
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• 2014

Persimmon juice dye-printed fabrics with printing were used for a Galot one-piece dress. The Galot dress was assessed in comparison to a white undyed one-piece dress of the same design through a wearing test conducted in a climatic chamber with an air temperature of $30{\pm}1^{\circ}C$, $50{\pm}5%$ R.H, and 0.2m/sec air movement on 4 healthy female subjects in their 20s. The subjects went through a 30-min stable period, a 30-min exercise of walking on a $5^{\circ}$ slope treadmill at 70m/min period, and a 20-min recovery period. In addition, a physiological reaction and subjective sensation were estimated. The results showed that significant differences were mostly observed from a sweating period that occurred during the latter half of the exercise. More specific results are as follows. First, skin temperature on the chest and mean skin temperature were significantly higher (p<.01) in rayon dyed sample dresses. Second, micro-humidity on the back showed a significant difference (p<.01). Both cotton and rayon persimmon juice dyed sample dresses produced lower microhumidity than their counterparts and as for cotton the difference occurred over the entire experimental period; however, it occurred after the middle of the exercise period for rayon. Third, the sweating rate on the back decreased in both cotton and rayon with persimmon juice dye but no significant difference was observed. Fourth, subjective three sensations revealed significant differences between cotton and rayon (p<.01), indicating that the subjects felt more cool, dryer and more comfortable in a cotton Galot. As described above, the analysis of physiological responses and the subjective sensation of undyed and dyed clothing shows the effect of persimmon juice dyeing. Persimmon juice dyeing also seemly increased air permeability, moisture regain and permeability facilitating body heat ventilation, as micro-humidity and sweat rate were lowered. However, this was not shown consistently in subjective responses on comfort especially when wearing rayon dresses.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.1883-1896
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• 2009

This paper explores the use of Korean wrapping cloths (bojagi) in the late Joseon period and the types of decorations applied to them. Korean wrapping cloths called bojagi are pieces of cloths used by households of all social classes for practical purposes such as wrapping presents and covering food. In addition to the basic purposes, the making of bojagi was also an activity to express the down-to-earth wishes and the satisfaction of creation by the designer. With regard to the decorative feature of Korean wrapping cloths, five types of, patchwork, embroidered, painted, printed, and oiled-paper wrapping cloths, were examined. The patchwork wrapping cloths (jogakbo) show the frugality of Joseon women in addition to the well-developed composition skill of lines and colors. The embroidered wrapping cloths were prepared for special rituals and ceremonies such as weddings. Painted wrapping cloths were decorated with a Chinese-colors technique (called dangchae) or sometimes with black ink painting. For printed wrapping cloths, various sizes of woodblock printings and roller printings were used. Although monotone black ink was the main color applied to the printing, there was also wrapping cloths made from chintz having brilliant fast colors. Oiled-paper wrapping cloths called sikjibo were in use only for covering food. Cut-out work was employed to decorate it.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1665-1673
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• 2013

Recently, the interest and demand on free formed structure providing aesthetic value as well as functionality has been increasing. Formwork has numerous advantages such as high strength, convenience, accuracy and good quality of surface roughness. Nevertheless, it increases construction cost and period to build complex shapes. For these purpose, deposition construction systems such as Contour Crafting and Concrete Printing have been developed with active collaboration between university and industry by applying the rapid prototyping technology to the construction industry in USA and England. Since there has been no related research in Korea, the possibility of spin-off technology and its fusion cannot be expected. In this paper, design elements including mechanical system and control system related to automatic deposition construction system prototype for constructing a free curved structure without mold are described. As for an appropriate material for the system, fiber reinforced mortar was selected by experiments on compressive strength, fluidity, viscosity and setting time. By performing transfer and extrusion experiments, the possibility of the development of deposition construction system was demonstrated. Based on this research results, it is required to keep the automatic deposition construction system improve and extend it into the new application area in construction industry.

• Clean Technology
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• v.28 no.4
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• pp.323-330
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• 2022

Microfluidic paper-based analytical devices (μPADs) have recently been in the spotlight for their applicability in point-of-care diagnostics and environmental material detection. This study presents a double-sided printing method for fabricating 3D-μPADs, providing simple and cost effective metal ion detection. The design of the 3D-μPAD was made into an acryl stamp by laser cutting and then coating it with a thin layer of PDMS using the spin-coating method. This fabricated stamp was used to form the 3D structure of the hydrophobic barrier through a double-sided contact printing method. The fabrication of the 3D hydrophobic barrier within a single sheet was optimized by controlling the spin-coating rate, reagent ratio and contacting time. The optimal conditions were found by analyzing the area change of the PDMS hydrophobic barrier and hydrophilic channel using ink with chromatography paper. Using the fabricated 3D-μPAD under optimized conditions, Ni²⁺, Cu²⁺, Hg²⁺, and pH were detected at different concentrations and displayed with color intensity in grayscale for quantitative analysis using ImageJ. This study demonstrated that a 3D-μPAD biosensor can be applied to detect metal ions without special analysis equipment. This 3D-μPAD provides a highly portable and rapid on-site monitoring platform for detecting multiple heavy metal ions with extremely high repeatability, which is useful for resource-limited areas and developing countries.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.2
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• pp.27-42
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• 2015

The aim of this research is to investigate the difference in the capturing opportunities for each type of venture companies in the industry undergoing competition of a dominant design and then figure out the reason why they can be successful. Existing studies on venture companies are focused on the way to enhance a firm's competencies by acquiring and combining its resources. However, it is important for startups which have a lack of resources and capabilities to capture the opportunity to survive by understanding a changing environment. This study is focused on opportunity capture and strategic response to a changing environment and attempts to select and observe startup companies which are able to capture the opportunity and enter the market in the industry undergoing dominant design competition. In order to find out its difference in different types of business, we select one case from hardware startups and the other from software startups. According to the result of this study, the hardware startup focuses on market extension by lowering their prices and the software startup strives to induce more users to participate by the universalization of enabling technology so as to extend and standardize their technology in the environment undergoing dominant design competition. This feature of environment leads the difference in the approach for successfully capturing opportunity and thus hardware firms need to recognize the opportunity with profit potential from relationship with a number of cooperative firms while software firms need to identify the opportunity for extension of enabling technology which can be used by many users.