• Design & Manufacturing
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• v.12 no.3
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• pp.19-24
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• 2018

Fused deposition Modeling (FDM) is one of the most widely used for the prototype of parts at ease. The FDM 3D printing method is a lamination manufacturing method that the resin is melted at a high temperature and piled up one by one. Another term is also referred to as FFF (Fused Filament Fabrication). 3D printing technology is mainly used only in the area of prototype production, not in production of commercial products. Therefore, if FDM 3D printer is applied to the product process of commercial products when considered, the strength and dimensional accuracy of the manufactured product is expected to be important. In this study, the mechanical properties of parts made by 3D printing with FDM method were investigated. The aim of this work is to examine how the mechanical properties of the FDM parts, by changing of processing FDM printing direction and the height of stacking layer is affected. The effect of the lamination direction and the height of the stacking layer, which are set as variables in the lamination process, by using the tensile specimen and impact specimen after the FDM manufacturing process were investigated and analyzed. The PLA (Poly Lactic Acid) was used as the filament materials for the 3D printing.

• Design & Manufacturing
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• v.6 no.2
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• pp.70-73
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• 2012

Drill process is usually used to manufacture a industry about processing, Therefore, the burr problem is very significant, The burrs took place when drill process. And then, sometimes, the burrs are often caused of some problems during automatic such as no good quality products and having good surface roughness products. And also, this paper had some experiments using magnesium. Specially, the magnesium is one of the non-ferromagnetic materials. Magnesium has attracted a lot of interest for using the industry. They offer a possible alternative to steel and aluminum in automotive and aero industries to satisfy the lightweight requirement. also, magnesium has good specific strength and absorbs vibration in occurring working process. So, it has good quality of product processing. And then, it is one of the lightest materials being used to electronic product's cases and automotive because of lightweight and miniaturization. But this material has not widely used all of the industry due to its natural property. If the magnesium is contacted water, it will cause the exploration. But, nowadays many of people study magnesium to safe their experiment and to widely use this industry.

• Journal of Life Science
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• v.12 no.1
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• pp.1-8
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• 2002

Antlers from deer species are alternative animal by-products. Due to the oriental trade, the velvet antler industry is rapidly emerging in North America. The unique biological property of antler wish a deciduous natural phenomenon offers the valuable model of biomedical research. Growing antlers showed different structures according to cell populations consisting of mesenchymes, chondroblasts, chondrocytes and osseous tissues from distal to proximal portions of main beam. Their structures were different from two tissues, cartilage and bone, in growing antlers. Zone of maturing ants calcifying chondrocytes referred as upper section was invaded by osteoblasts indicating the occurrence of endochondral ossification. The cartilaginous tissues were gradually replaced by osseous tissues downward. The bony tissues referred as the middle and base sections in this thesis contained spongy bone and cortical bone structure in the difference of the degree of mineralization antral the thickness of cortical bony in adjacent to outer velvet layer. In addition, the endocrinological regulators such as testosterone, prolactin, growth hormones and other growth factors are actively involved in the unique deciduous nature shown in the growth and development of antler.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.254-260
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• 1995

Yogurt base were prepared from milk added with skim milk powder or Aloe vera powder and femented with lactic acid bacteria(the single or mixed strain of Lactobacillus bulgaricus and Streptococcus thermophilus). The yogurt product were evaluated for acid production(pH, titratable acidity), number of viable cell, viscosity, sensory property and quality-keeping property. The composition of organic acid were also analyzed by HPLC. Addition of Aloe vera remarkably accelerated acid production, and titratable acidity of Aloe vera yogurts(1.293∼1.407%) after 24 hours incubation was higher than that of yogurts added with only skim milk powder(9.98∼1.110%). Yogurt fermented with the mixed strain of L. bulgaricus and Sc. thermophilus was more acidic than that of single strains. The propagation of lactic acid bacteria was stimulated by Aloe vera and the number of viable cell after 24 hours incubation were above 9.87log CFU/ml. Viscosity of Aloe vera yogurt(3,860∼4,300CPS) was higher than that of yogurt with only skim milk powder(2,402∼2,604CPS). The overall sensory score of Aloe vera yogurt femented by mixed strain was the best of tested yogurt. When yogurt with Aloe vera was kept at 5℃ for 15 day, it's quality-keeping property was relatively good. The major organic acid of Aloe vera yogurt was lactic acid and lactic acid content of yogurt increased by addition of Aloe vera powder. The citric acid content decreased wtih fermentation and malonic acid, pyroglutaric acid and α-ketoglutaric acid were analyzed out a little.

• Journal of Power System Engineering
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• v.22 no.6
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• pp.51-57
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• 2018

In Korea, the Air Quality Conservation Act and the Petroleum and Petroleum Substitute Fuel Business Act stipulate certain quality standards for fuels distributed in Korea, thereby striving to reduce vehicle performance and emissions. Domestic petroleum products import and produce all the crude oil from each oil refiner so that the quality of the petroleum product is different according to the characteristics of the crude oil. As a result, vehicles have been improved by using the physical properties calculated through the physical property measurement that has tried to improve the accuracy of the measurement of the energy consumption efficiency of the automobile by using standard fuel from abroad. In this study, the same test procedure and method as the test method of domestic gasoline vehicle emission are applied using four samples of gasoline and the latest gasoline vehicle which are actually distributed, and the performance evaluation is performed. The purpose of this study is to contribute to improvement of vehicle technology and fuel quality by collecting necessary basic data and obtaining data on the effect of differences in gasoline property on vehicle emissions. The results of the test showed that the emission of gases (NMOG, CO) from gasoline vehicles was the most influenced by the sulfur content, unlike the previous studies that the vehicles emission had the greatest influence on the distillation characteristics and the specific gravity of aromatic compounds. The catalytic reaction such as the poisoning action of the three-way catalyst which is the abatement device was interfered and the emission was increased. The distillation characteristics and specific gravity of aromatic compounds were found to affect the emission of vehicles. According to the physical properties of the fuel, the emission difference was 28.0% in the urban mode and 17.6 % in the highway mode.

• 한국금형공학회:학술대회논문집
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• 2008.06a
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• pp.51-54
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• 2008

Drill process is usually used to manufacture a industry about processing, Therefore, the burr problem is very significant, The burrs took place when drill process. And then, sometimes, the burrs are often caused of some problems during automatic such as no good quality products and having good surface roughness products. And also, this paper had some experiments using magnesium. Specially, the magnesium is one of the non-ferromagnetic materials. Magnesium has attracted a lot of interest for using the industry. They offer a possible alternative to steel and aluminum in automotive and aero industries to satisfy the lightweight requirement. also, magnesium has good specific strength and absorbs vibration in occurring working process. So, it has good quality of product processing. And then, it is one of the lightest materials being used to electronic product's cases and automotive because of lightweight and miniaturization. But this material has not widely used all of the industry due to its natural property. If the magnesium is contacted water, it will cause the exploration. But, nowadays many of people study magnesium to safe their experiment and to widely use this industry.

• Journal of Magnetics
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• v.21 no.2
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• pp.209-214
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• 2016

This paper analyzes the magnetic property according to the machined shape of steel material with non-oriented silicon steel (50PN470/50A470), that is most commonly used in the design of electrical equipment. Toward this end, specimens were produced and divided into Bar-Specimen (Epstein Frame Tester) and Ring-Specimen (Toroidal Ring Tester). The characteristics of the electrical Silicon steel were measured using the instruments solely dedicated to measuring each specimen. The core loss of the Bar-Specimen, which is commonly used, was found to be less than that of the Ring-Specimen. This is a very important design factor in achieving the objectives of improving the product efficiency and predicting the performance of electrical equipment. It serves as a critical point of view in order to reduce the error between design value and product value. A comparative analysis was conducted regarding various characteristics (Hysteresis, B-H characteristic, Iron loss, Minor loop, Coercive force, Residual magnetic flux density, etc.) of the electrical silicon steel considered in the design of the electrical equipment according to the specimen.

• Fashion & Textile Research Journal
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• v.25 no.1
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• pp.62-71
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• 2023

Recently, interest in natural fabric materials that are not harmful has increased, and hemp is being studied as a new eco-friendly product. This study produced hemp fabric with improved flexibility and increased antibacterial properties by blending it with Hanji yarn. Various weaving methods were proposed to overcome the rough physical properties of hemp, and the functions of the developed products were evaluated through antibacterial tests. The mixing ratios of hemp and Hanji yarns was 50% hemp: 50% Hanji weft, 70% hemp: 30% Hanji weft, 30% hemp: 70% Hanji weft, and 100% hemp. Overall, the higher the ratio of Hanji yarn, the higher the fastness property, and the higher the ratio of hemp yarn, the higher the flexibility of the fabric, which was evaluated to be comfortable to wear. The 99.9% antibacterial properties of hemp products were considered to contribute to maintaining the health of modern people. Owing to its high intensity and high air permeability, it is considered highly usable in the production of children's clothing with a lot of activity. It was evaluated as an advantage that the disadvantage of hemp, which was limited as a material for summer clothing, was broadened to use for all seasons due to the fusion of Hanji. Otherwise, low consumer satisfaction as an outdoor wear is a disadvantage because hemp products had low elasticity and wrinkles.

• Korean Journal of Health Education and Promotion
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• v.23 no.3
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• pp.65-83
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• 2006

Objectives: This is one of the first efforts to describe incidence of alcohol-related problems and to identify environmental correlates associated with them among colleges. Methods: Date were collected by a sample of 105 college administrators who are in charge of student affairs in colleges nationwide through self-administrated questionnaire. Both logistic and linear multiple regression analyses were employed to identify the correlates associated with alcohol-related problems. Results: Most of colleges(76.6%) under study reported to have at least one alcohol-related problem in previous years. Interpersonal violence was alcohol-related problem taken placed most frequently, followed by making noise episode, having property damaged and motor vehicle accidents. Logistic regression analysis identified factors associated with incidents of alcohol related problems. They included being private colleges, numbers of prevention activities, product promotion and marketing by alcohol industry and alcohol accessibility to drinking context. Multiple regression analyses showed that correlates associated with numbers of alcohol-related problems included being a private college, being located in rural area, having drinking density, product promotion and availability of alternative activities to drinking. Conclusions: Environmental correlates were associated with incidence of alcohol related problems in colleges nationwide. Policy implications were discussed.

• Journal of the Korean Society of Food Culture
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• v.24 no.3
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• pp.245-255
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• 2009

As multinational brands have made inroads into domestic food service industry, and its recognition has been high to consumers, This research has tried to examine the general identity of brand, their recognition, and re-purchase behaviors. The purpose of this study is to inquire into how the brand value by brand identity was caused by recent development of food service industry, and how it had an effect on the purchase behaviors of them. In particular, factors of general identity have a significant effect on the revisit and purchase intention, as the image and ads of family restaurant among brand property factors of family restaurant showed an significant effect on the revisit intention. This study was made with priority given to the brand identity as four brand factors such as product brand, organizational brand, community brand and design brand based on the confidence. Results found that the community brand and design brand had a significant difference on purchase intention. Consequently, it has been suggested that the marketing strategies to make the brand identity strong have to be established with various brand enhancement tactics in the food service industry.