• Korean Journal of Materials Research
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• v.32 no.1
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• pp.9-13
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• 2022

Bullets flying with a light from the back are called "tracers". Tracers are ignited by the combustion gas of the propellant and emit bright light that allows the shooter to visually trace the flight path. Therefore, tracers mark the firing point for allies to assist shooters to hit target quickly and accurately. Conventional tracers are constructed with a mixture of an oxidizing agent, raw metal, and organic fuel. Upon ignition, the inside of the gun can be easily contaminated by the by-products, which can lead to firearm failure during long-term shooting. Moreover, there is a fire risk such as forest fires due to residual flames at impact site. Therefore, it is necessary to develop non-combustion type luminous material; however, this material must still use the heat generated from the propellant, so-called "thermoluminescence (TL)". This study aims to compare the TL emission of Dy³⁺, La³⁺ and Ho³⁺ doped MgB₄O₇ phosphors prepared by solid state reaction. The crystal structures of samples were determined by X-ray diffraction and matched with the standard pattern of MgB₄O₇. Luminescence of various doses (200 ~ 15,000 Gy) of gamma irradiated Dy³⁺, La³⁺ and Ho³⁺ (at different concentrations of 5, 10, 15 and 20 %) doped MgB₄O₇ were recorded using a luminance/color meter. The intensity of TL yellowish (CIE x = 0.401 ~ 0.486, y = 0.410 ~ 0.488) emission became stronger as the temperature increased and the total gamma-ray dose increased.

• Korean Journal of Optics and Photonics
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• v.33 no.5
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• pp.218-229
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• 2022

We have investigated reliable inspection methods for finding the defects generated during the manufacturing process of lightweight, large-aperture satellite telescope mirrors using silicon carbide, and we have measured the basic physical properties of the mirrors. We applied the advanced ceramic material (ACM) method, a combined method using liquid-silicon penetration sintering and chemical vapor deposition for the carbon molded body, to manufacture four SiC mirrors of different sizes and shapes. We have provided the defect standards for the reflectors systematically by classifying the defects according to the size and shape of the mirrors, and have suggested effective nondestructive methods for mirror surface inspection and internal defect detection. In addition, we have analyzed the measurements of 14 physical parameters (including density, modulus of elasticity, specific heat, and heat-transfer coefficient) that are required to design the mirrors and to predict the mechanical and thermal stability of the final products. In particular, we have studied the detailed measurement methods and results for the elastic modulus, thermal expansion coefficient, and flexural strength to improve the reliability of mechanical property tests.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.3
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• pp.111-125
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• 2022

Recently, the MZ generation has been leading overall fashion trends, and fashion companies focus on design, marketing, and new products targeting the MZ generation. However, it is expected that a fit problem may occur if the M and Z generations are combined when producing clothing. Therefore, this study aims to analyze the differences between the two groups by comparing the body size according to the classification of the M and Z generations. In addition, this study analyzes whether the body shape of the MZ generation is different from the past generations and analyzes major changes in body size for clothing manufacturing through graphical visualization. As for the research method, a t-test was conducted to verify the significant difference between the measurements for each age group. Generation M was defined as those who are 27-39 years old, and Generation Z was defined as those who are 20-26 years old. In order to examine the changes in body measurements according to the measurement year, the 7th Size Korea and 8th Size Korea data were analyzed. In order to examine the visual changes according to the measurement year and age group, major measurements of clothing construction were analyzed. As a result, it was found that Generation M had a significantly higher height item than Generation Z. Also, in terms of circumference, width, and thickness, Generation M was larger than Generation Z. But the size of the bra cup was larger in Generation Z than Generation M. As a result of analyzing the body size changes, in the height item, the 8th Size Korea measurements were found to be significantly higher in shoulder height and navel level waist height. In the length and circumference items, the 8th Size Korea measurements were larger than the 7th. In the width, thickness, and other items, the 8th measurements were larger than the 7th.

• Journal of Conservation Science
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• v.37 no.3
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• pp.270-281
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• 2021

The Yongjam of Oejae, Yi Dan-ha's wife, is an ornamental hairpin with a dragon-shaped engraving; designated as National Folklore Cultural Heritage No. 4. It is also a component of the ceremonial costume, and an artifact of great value as it clearly identifies the position of the wearer and the period of this artifact. The Yongjam has been well preserved in general; however, various pollutants and corrosive products have affected the engraved patterns, requiring conservation treatment. Furthermore, a non-destructive analysis was conducted to identify the components of the materials and the manufacturing techniques used in the ornament. The Yongjam is hollow inside to reduce its weight when placed in the hair and has a color contrast of gold, red, and black. The decorative part and the body were made separately. That is, the body was made from an alloy of copper, silver, and zinc, and its joint was elaborately connected without any overlaps. In the decorative part, different alloy ratios were identified in the dragon's face, beard, horn, body, and fin. Further, for the dragon's face with its delicate patterns, an alloy of silver and copper was used, likely to make the face appear as realistic as possible.

• Journal of Life Science
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• v.32 no.5
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• pp.362-367
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• 2022

Hempseed, a dehulled Cannabis fructus, has high nutraceutical potential. It has plenty of essential amino acids, vitamins, and essential polyunsaturated fatty acids, including α- and γ-linolenic acid. Increased exercise capacity, cognitive function, and ameliorative effects against hypercholesterolemia, neuro-inflammation, thrombus formation, and learning and memory impairment were reported in hemp-seed oil-administered models. Therefore, the market prices of hempseed oil are 45~140-fold higher than the other plant-derived oils, such as soy, corn, olive, canola, or linseed oil. In this study, instead of FTIR (Fourier Transform Infrared Spectroscopy) or FTIR-Raman spectroscopy, a simple UV-Vis spectrophotometry method was developed to authenticate the hempseed oil. Measurements of absorbance at 245, 305, and 415 nm of oils and calculations of 245/415 and 315/415 nm provided that the ratios of 245/415 and 315/415 nm of authentic hempseed oils were 12.9 and 9.6, respectively. The 245/415 and 315/415 nm of soy oil, corn oil, canola oil, and linseed oil were 35.4~61.8 and 29.7~50.8, respectively. This simple UV-Vis spectrophotometry method could also be applied to differentiate hempseed oil from blended oil products in markets.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.1
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• pp.1-18
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• 2023

Similar software is often developed with the Clone-And-Own (CAO) approach that copies and modifies existing artifacts. The CAO approach is considered as a bad practice because it makes maintenance difficult as the number of cloned products increases. Software product line engineering is a methodology that can solve the issue of the CAO approach by developing a product family through systematic reuse. Migrating product families that have been developed with the CAO approach to the product line engineering begins with finding, integrating, and building them as reusable assets. However, cloning occurs at various levels from directories to code lines, and their structures can be changed. This makes it difficult to build product line code base simply by finding clones. Successful migration thus requires unifying the source code's file path, class name, and method signature. This paper proposes a clustering method that identifies a set of similar codes scattered across product variants and some of their method full paths are different, so path unification is necessary. In order to show the effectiveness of the proposed method, we conducted an experiment using the Apo Games product line, which has evolved with the CAO approach. As a result, the average precision of clustering performed without preprocessing was 0.91 and the number of identified common clusters was 0, whereas our method showed 0.98 and 15 respectively.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.6
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• pp.463-470
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• 2022

Intravenous injection is widely used for patient treatment, including injection drugs, fluids, parenteral nutrition, and blood products, and is the most frequently performed invasive treatment for inpatients, including blood collection, peripheral catheter insertion, and other IV therapy, and more than 1 billion cases per year. Intravenous injection is one of the difficult procedures performed only by experienced nurses who have been trained in intravenous injection, and failure can lead to thrombosis and hematoma or nerve damage to the vein. Nurses who frequently perform intravenous injections may also make mistakes because it is not easy to detect veins due to factors such as obesity, skin color, and age. Accordingly, studies on auxiliary equipment capable of visualizing the venous structure of the back of the hand or arm have been published to reduce mistakes during intravenous injection. This paper is about the development of venous detection equipment that visualizes venous structure during intravenous injection, and the optimal combination was selected by comparing the brightness of acquired images according to the combination of near-infrared (NIR) LED and Filter with different wavelength bands. In addition, an image processing algorithm was derived to threshehold and making blood vessel part to green through grayscale conversion, histogram equilzation, and sharpening filters for clarity of vein images obtained through the implemented venous detection experimental module.

• Journal of Life Science
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• v.32 no.4
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• pp.303-309
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• 2022

Dystaenia takesimana is an endemic plant found only in Korea, especially on Ulleung Island. The leaves and roots of D. takesimana have been used as food, forage, and oriental medicine. Anti-bacterial, anti-inflammation, antioxidant, and α-glucosidase inhibition biological activities have been reported in the plant's root extract. However, studies concerning the anti-thrombosis activities of D. takesimana are still in the rudimentary stage. In this study, the extracts of the leaf (DT-L), stem (DT-S), and root (DT-R) of D. takesimana were prepared using 70% ethanol, and their anti-thrombosis activities were evaluated. DT-L extracts (0.25 mg/ml) showed strong inhibitions against platelet aggregation, comparable to aspirin, with strong radical scavenging activities. Furthermore, the DT-L extract did not show any RBC hemolysis up to 1 m/ml. The ant-coagulation and antioxidant activities of the DT-S extract were ignorable. While the DT-R extract showed inhibitions against thrombin and blood coagulation factors, it also showed strong platelet aggregation. This is a first report of the anti-thrombosis activities of D. takesimana, and our results suggest that DT-L could be developed as a valuable bioresource for high value-added products.

• Journal of the Korean Society of Floral Art and Design
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• no.43
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• pp.81-100
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• 2020

Since sustainable packaging of flower basket designs that are sold from florist shops is needed for both the seller and the buyer, studying of second packaging of flower basket design has begun. In this study, based on the survey that has been done in 2019, and the analysis of the interview that has been done in 2020, the suggestion of sustainable packaging development is the purpose. The definition of flower basket design was done and surveys of the status of domestic flower basket designs' second packaging were done in accordance with the type of basket which is an object, transportation, and characteristic of a florist shop. For sustainable packaging, based on physical theory, second packaging which depends on the packaging that includes design factor, transportation final destination has to be different. The factors to be considered as sustainable packaging are the quality of opaque paper, the necessity of first packaging, packaging structure that can fix an object, the form of second packaging influenced by types of transportation. Suggestions for packaging development included new materials for first packaging, eco-friendly objects that can be recycled and reused, structural packaging design, standardization and variability of packaging, protection of floristry which is the fundamental purpose of packaging, and brand advertisement effect. Based on the result of this study further designs of packaging will be commercialized. This study is significant for serving the opportunity of new packaging design for futuristic floristry that fit for unmanned system and studying of categories of products.

• Journal of fish pathology
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• v.35 no.1
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• pp.103-111
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• 2022

This study has been performed to investigate the potential effects of by-product discarded after probiotics production (BPPP) on growth performance, immune gene expression, innate-immunity status, and disease resistance of carp, Cyprinus carpio. For 3 weeks, carp were fed four diets containing different levels of BPPP at 0, 0.1, 0.2 and 0.5% per kg of normal diet. Every 7 days of feeding, immune-related gene expression, serum lysozyme activity and ACH₅₀ were analyzed. Growth rates and challenge test with E. tarda were conducted after 3 weeks of BPPP feeding. Both lysozyme activity and ACH₅₀ were significantly (p<0.05) increased in all BPPP supplemented groups compared to the control at every 7 day for 3 weeks of feeding trial. The gene expression of pro-inflammatory cytokines, IL-1β and TNF-α was significantly (p<0.05) up-regulated until 21 days of feeding in all groups except for 0.2% group on day 7 post feeding. The anti-inflammatory cytokine IL-10 gene expression was only significantly (p<0.05) increased in 0.1% group on day 7 and decreased (p<0.05) on day 14 in all BPPP supplemented groups. On day 21, the IL-10 gene expression was augmented (p<0.05) in all groups. SOD gene expression was significantly (p<0.05) increased compared to the control on day 14 and 21 post feeding, whereas no significant difference was observed on day 7. In challenging test, 0.2%, 0.1%, 0.5% and control group showed 80%, 70%, 60% and 40% of survival rate, respectively. Feed conversion rate was only improved in 0.5% group. In conclusion, the present study indicates that dietary BPPP suplementation improved growth performance, innate immune response and bactericidal activity in carp.