• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.86-89
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• 2018

This paper introduces a ZigBee network-based four-lane lap time measurement system that can be set up for short-distance races. The instructions "Ready-Set-Go" can be announced at the entry point node when the start button is pushed, and foot switches installed at the exit point node can be stepped on by the runner for lap time measurement of the race. The start and exit point nodes are connected to a ZigBee network to communicate time synchronization packets. The exit point node maintains synchronized local time within 10 ms at most. The system does not need expensive measurement equipment and provides lap time recording in a more convenient manner than conventional lap time measurement methods.

• Journal of Korea Foundry Society
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• v.37 no.1
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• pp.1-13
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• 2017

The purpose of this study is to increase the part recovery rate (to more than 70%) during the casting of a ductile cast iron turbo charger housing using a heater around the riser. Before creating a casting mold, various runner and riser systems were designed and analyzed with a casting simulation analysis tool. The design variables were the heater temperature, top insulation, riser location, riser diameter and the riser shape. During the feeding from the riser to the part, the reverse model was better than the forward model. When heating the riser (above $600^{\circ}C$), solidification of the riser was delayed and the feeding effect was suitable compared to that without heating. At a higher heating temperature, less solidification shrinkage and porosity were noted inside the part. On the basis of a casting simulation, eight molds were fabricated and casting experiments were conducted. According to the experimental conditions, external and internal defects were analyzed and mechanical properties were tested. The ultimate tensile strength and elongation outcome were correspondingly more than 540MPa and 5% after a heat treatment. In addition, a maximum part recovery rate of 86% was achieved in this study.

• Journal of Nutrition and Health
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• v.17 no.1
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• pp.10-19
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• 1984

The Purpose of this study was to investigate the food preferences of college students of Korea. The survey was conducted on november, 1981 through the questionnaires. The subjects were 1184 male and 1241 female students of 9 universities. The results obtained were summarized as follows : 1) Preferences of staple foods : Cooked rice was preferred most by the subjects. Male liked rice more than female, whereas female liked bread and noodle more than male. Among the different kinds of rice, bread, and noodles, the following food items were favored by the subjects. (plain rice, red bean rice and soybean rice ; salad bread and vegetable bread ; Nangmyun and Bibim Kooksu). The foods not preferred were barley rice, instant noodle and soybean milk noodle. 2) Preference of side - dishes : Among the kinds of side - dishes by different preparation methods, stews were the most favored and the next favored were soups by the subiecls whereas female showed lower preference of soups than male subjects Most disliked kinds of side-dishes were changachi and moochim. For example, side-dishes which showed higher preference in each preparation method were stew (Kimchi stew and Soybean paste stew), soup (Beef soup and Seaweed soup), kimchi (Korean cabbage Kimchi), Bockeum (Sauted beef and Sauted Kimchil, cheon(Beef Cheon, fish Cheon), Kui(broiled saury and broiled yellow tail runner), Chorim(braised cuttle fish and braised fish cake), Namul(sliced radish, cucumber, and spinachi), and Changachi (dried radish). The side-dishes which showed lower preference were Alaskan pollack soup, soybean curd residue stew, cabbage Kimchi, liver Cheon, sauted liver, hairtail Chorim, radish rootNamul, and dried radish root Changachi. 3) Preferences of snacks. Fruits apple, peach, pear) were the most preferred snacks by the subjects. Male preferred ginsang tea whereas famale preferred coffee. Both bate and female subjects showed higher preference of milk and lower preference of sweets. 4) Preference of one-dish meals : No one dish meal were disliked by the subjects. Male liked Bockeum-Bab more than female, and female liked Mandukuk more than male subjects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.610-615
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• 2016

Diverse accessories are used in automobiles, such as navigation systems, front and rear cameras, spoilers, and sun visors. Sun visors block sunlight so that drivers can drive safely with a better view, and they are used in many automobile designs. However, when large plastic products are manufactured using injection molding, there are many difficulties that develop, like weld lines, short shots, flow marks, imperfections, and distortion. In this study, a CAE simulation was conducted based on previous results to predict potential problems in the injection molding of large products. The flow characteristics up to complete charge for the melting resins were captured using a computer-aided engineering simulation. The temperature departure on the front part of a flow was about $10^{\circ}C$ and very stable. The practical ejecting time of the cold runner was about 70 seconds in the simulation. Finally, the capability of a suitable injection machine was calculated and recommended by prediction of the injection pressure and the die clamping force.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.522-533
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• 2007

Statement of problem: Despite of the recent development of the titanium casting system methods, the casting defects such as imperfect casting and internal porosity were frequently observed. Purpose: The purposes of this study were to compare and measure the castability, microhardness, and surface reaction between Grade 2 pure titanium and Ti-6Al-4V by casting these alloys from the different sprue design conditions. Material and methods: Depending on the sprue designs and titanium alloys, 42 ready-made wax patterns were used. By analyzing the remodeling of the cast, internal porosity, microhardness, and titanium surface layer of SEM, there were several results we observed. Results: 1. The measured castability of titanium were categorized in the ascending order: individual sprue group, runner bar group, and single group. This data are based on the statistically signigicant differences. 2. The castability of titanium has not showed the statistically significant differences among the alloys. However, CP-Ti groups were superior to Ti-6Al-4V groups by showing the noticeable castability. 3. The surface layers of the castings of all groups have showed $5{\mu}m$ titanium oxide layers irrespective of sprue designs and titanium alloys. Conclusion: From the above study results, by fabricating the restorations from the centrifugal casting machine direct sprue designs revealed better castability. As we increased the number of sprues in the wax pattern, it revealed better castability. The castability of pure titanium rather than that of Ti-6Al-4V was remarkable. To fabricate the complex forms of the restorations, further researches on the efficient sprue designs and titanium alloys must be made.

• Journal of the Korean Society of Costume
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• v.38
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• pp.51-72
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• 1998

Futurists objected the existent style, that is the conventional fashion, and took part in these disciplines of fashion to make clothes the instruments being able to represent the individuality. Giacomo Balla and fortunato Depero, pain-ters who in 1915 were to work with Diaghilev's company, were the first to see clothing as a dynamic interfaced between th body and the atmosphere, between physical gestures and the urban context, which could be translated into encounters between forms and colours, volumes and architecture. For them, clothing began to exist as an object and an event, something to be removed from a mainly static conception and made mobile, active. The interaction between movement and clothing was based on the relativity of perception : the appearance and disappearance of the body produced points without dimension or duration which served, as Balla wrote in the Futurist Mnaifesto of Men's Clothing to“renew incessantly the enjoyment and impetuous movement of the body”. The historical achievement in the effort for the reformation of Futurist, Art to Wear. First, for Futurist, clothing is removed from a static conception and focused on dynamics. Second, Balla used asymmetry in men's clothing. Moreover he supposed dynamic men's clothes by using optical intersection. Third, the after image of Chronophotograph represented rapidity. This rhythmic expression is the fore-runner in Optical and Kinetic Art of Visual Art. Fourth, Futurist emphasized flexibility in fashion. They aimed to create‘Clothing Machines’whose parts would interact to aceelerate the real and virtual, inner and outer movement of the human being. Fifth, the variety and short life of cutting skills and colors are focused and‘Fast Substance’in fashion is admitted by Futurists. Futurist concern with clothing was not lim-ited its appearance in terms of cut and colour. What important was also the way it appeared and disappeared according to fashion. It was a“fast substance”, able to reflect rapid, sudden changes of social and aesthetic taste. To reach to the aim of internationalization, Gesamtkunstwerk in our Art to Wear, it is extremely meaningful to examine art fashion which is created under the conception of Gesamtkunstwerk production of avang garde artist in the early 20th century and look at formative conscious of truth, goodess and beauty synthetically which they faced on their works of art.

• The Korean Fashion and Textile Research Journal
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• v.16 no.4
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• pp.532-542
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• 2014

This study developed a practical knitwear design with applying the pattern of Queen Yeong's pearl pouch. The ume flower pattern of pearl pouch was simplified to be one repeat pattern, and four simulated knit pattern samples of G-A, G-B, R-A, and R-Bwere made with cable, cross, and two background colors of gray and red using Texpro V.11.0. The items of design application were selected after an interview with a panel of university students in their twenties and knit samples were produced by hand knitting. The small sized G-A for the partial ornament of hat, sweater, skirt, kitchenware case and accessories; the long sized G-B for the tuck of sleeves, hem of skirt and one-piece dress, partial ornament of sweater, scarf, and curtain decoration: the small sized R-A was preferred for point ornament of pouch, boots, hat, partial ornament of children's fashion products and accessories: the long sized R-B for table runner, leg warmer, tuck of sleeves, skirt hem, necktie, and scarf. The knit samples were formulated with partial ornaments attached on dress and props or connected each other. Colors of pastel and navy were also presented to meet the demands of panels. The study placed a limit on the slight difference between the simulation samples and knit samples due to the characteristics of threads and hand tension. The color variation for multiple coordination and activation to reduce the piece rate for young customers remains to be discussed in the near future.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.2
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• pp.248-255
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• 2013

The objective of this study is to optimize the Metal Injection Molding(MIM) process with design of experiments(DOE) and numerical analysis. To derive the optimal process condition, experiment or numerical analysis was performed under various process conditions. To analyze the interaction among influential factors contributing to the temperature at flow front and response surface in MIM, both central point and axial point were added to the full factorial design with 2 levels and 5 factors and then their impacts on response variable in 43 experimental conditions were analyzed and the significance was evaluated. As a result, sprue, runner, and gate were completely filled in about 0.247 seconds after injection, the front part of the green body was filled in about 0.3344 seconds, the green body except gate, etc changed to almost solid state in about 3.29 seconds, the Packinging pressure was completed in about 6.29 seconds, and the green body inside and outside and sprue, etc became solid in 13.2 seconds. The impact of individual or reciprocal action of factors on the temperature at flow front was analyzed through regular probability, test statistics, main effect, and interaction effect. As a result, of a total of 31 combinations of factors, 9 unit factors and reciprocal actions were significant, and the screening was also possible. A proper regression equation was drawn with regression analysis and response surface design on the response variable of temperature at flow front, and the applicability could be verified.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.224-230
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• 2013

The objective of this study was to identify the content of phenolic and volatile organic compounds in edible and non-edible parts of 'Seolhyang' strawberry plants. We performed a comparative chemical analysis of the compounds found in roots, leaves, petioles, runners, and unripe and ripe fruits during vegetative propagation and reproductive growth. The contents of ellagic and gallic acids in the leaves of runner plants during vegetative propagation were $7.36{\pm}1.10$ and $5.07{\pm}3.66mg{\cdot}g^{-1}$ FW, respectively, and were higher than those in the other parts. The main volatile organic compound was identified as 3-hexen-1-ol, and it was mostly detected in leaves. The content of ellagic acid in leaves during reproductive growth was $12.96{\pm}2.30mg{\cdot}g^{-1}$ FW, while that in the other parts was below $6.00mg{\cdot}g^{-1}$ FW. The content of gallic acid in unripe fruits was $2.75{\pm}0.48mg{\cdot}g^{-1}$ FW and was higher than that in the other parts. Ripe fruits contained the lowest contents of ellagic and gallic acids but contained the most diverse volatile organic compounds, including sesquiterpenes, among the tested plant parts. The results indicate that non-edible parts (e.g., leaves and unripe fruits) of strawberry plants can be used as a raw material for antioxidant and anti-inflammatory agents, and edible parts (i.e., ripe fruits) can be available for making an essential oil.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.61.2-61.2
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• 2010

GMTNIRS (the GMT Near Infrared Spectrograph) is one of the first generation instrument candidates for GMT (Giant Magellan Telescope). Conceptual design studies for nine instruments were proposed last year, and the GMT organization selected 6 instruments including GMTNIRS for the next phase. GMTNIRS will be developed by an international collaboration between KASI and UT(University of Texas). KASI and UT have been also developing IGRINS (the Immersion Grating Infrared Spectrometer) which is a fore-runner instrument of GMTNIRS since 2009. In this talk, we will present the instrument details and development plan, and discuss the science case for GMTNIRS.