• Journal of Powder Materials
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• v.13 no.6 s.59
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• pp.415-420
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• 2006

Nanostructured metallic materials are synthesized by bottom-up processing which starts with powders for assembling bulk materials or top-down processing starting with a bulk solid. A representative bottom-up and top-down paths for bulk nanostructured/ultrafine grained metallic materials are powder consolidation and severe plastic deformation (SPD) methods, respectively. In this study, the bottom-up powder and top-down SPD approaches were combined in order to achieve both full density and grain refinement without grain growth, which were considered as a bottle neck of the bottom-up method using conventional powder metallurgy of compaction and sintering. For the powder consolidation, equal channel angular pressing (ECAP), one of the most promising method in SPD, was used. The ECAP processing associated with stress developments was investigated. ECAP for powder consolidation were numerically analyzed using the finite element method (FEM) in conjunction with pressure and shear stress.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.463-466
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• 2004

This paper describes an image processing algorithm for recognition of small-obstacles using a camera and program for a mobile robot in indoor environment. Mobile robot could meet small-obstacles such as a small plastic bottle of about 1l in quantity, a small box of 7$\times$7$\times$7 cm$^3$ in volume, and so on in its designated path, and could be disturbed by them in the locomotion of a mobile robot. So, it is necessary to research on the image processing algorithm for recognition of small-obstacles using a camera and program. In this paper, 2-D the image processing algorithm for recognition of small-obstacles using a camera and program for a mobile robot in indoor environment was developed. The characteristic test of the developed program to confirm the recognition of small-obstacles was performed. It is shown that the developed program could recognize small-obstacles accurately.

• Journal of the Korean Society of Food Culture
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• v.10 no.5
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• pp.419-425
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• 1995

General views of 1,436 housewives respondents through the country on commercial kochujang (fermented hot pepper-soybean paste) were surveyed by questionnaires. The 65.0% of total respondents had experience of purchasing commercial kochujang on the market, mostly super market (43.0%) of respondents, and the respondents who has job and live in apartment purchased the commercial products more often than the others (80.5%). The reason for purchasing commercial products were convenience (36.1%) and short of time (13.0%). The critera for purchasing commercial product were previous experience (40.1%) and well known trademark (20.6%) and not for purchasing were concerning of noxiousness (29.2%) and inferior taste (25.0%). Respondents prefered glass packing (44.3%) and plastic bottle (20.2%) of 500 g pack for single usage (42.3%). The most important standards for kochujang taste were pungency (59.1%) and savory taste (28.6%). The problems indicated to commercial products were inferior taste (32.2%), especially too sweet (52.6%), and safety (20.6%).

• Journal of Powder Materials
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• v.11 no.3
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• pp.233-241
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• 2004

In this study, bottom-up type powder processing and top-down type SPD (severe plastic deformation) approaches were combined in order to achieve both full density and grain refinement of Al-20 wt% Si powders without grain growth, which was considered as a bottle neck of the bottom-up method using the conventional powder metallurgy of compaction and sintering. ECAP (Equal channel angular pressing), one of the most promising method in SPD, was used for the powder consolidation. The powder ECAP processing with 1, 2, 4 and 8 passes was conducted for 10$0^{\circ}C$ and 20$0^{\circ}C$ It was found by microhardness, compression tests and micro-structure characterization that high mechanical strength could be achieved effectively as a result of the well bonded powder contact surface during ECAP process. The SPD processing of powders is a viable method to achieve both fully density and nanostructured materials.

• Advances in concrete construction
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• v.12 no.6
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• pp.461-467
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• 2021

Polyethylene-terephthalate (PET) from bottle waste and linear low-density polyethylene (LLDPE) from barrels and tanks waste are widely available and need to be recycled. Recycling them in concrete and mortar is an alternative solution for their disposal. In this study various quantities of sand (5%, 10%, 15% and 20%) were substituted by powder from LLDPE waste. In addition, PET waste fibers (corrugated, straight) were added to the mortar with different percentages (0.5%, 1%, 1.5% and 2%) of cement mass. This paper evaluate the mechanical and physical properties of the composites in fresh (workability, air content and density) and hardened state (compressive and flexural strength, water absorption and total shrinkage). From the experimental results, it can be concluded that the strengthening in tensile of the mortar with plastic waste corrugated fibers is improved. Other important results are that the water absorption and the density rate are less than that of the ordinary mortar.

• Elastomers and Composites
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• v.57 no.4
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• pp.138-146
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• 2022

Research on the reduction of plastic use to prevent environmental pollution is urgently needed. Accordingly, studies on reducing the weight of polyethylene terephthalate (PET) bottles are currently being conducted. PET bottles are fabricated by injection stretch blow molding. In this study, stretch blow molding for fabricating PET bottles using preform studied through a computer simulation. Blowing characteristics are analyzed by varying the start time of the pre-blow, which is one of the process conditions of stretch blow molding. Simulation results and the preform inflation process are presented, and the parameters of stretch ratio, stretching path, thickness distribution, and weight distribution of blown PET bottles are investigated.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.547-549
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• 2022

최근 소비경제의 폭발적 성장과 더불어 쓰레기로 인해 우리 생활 주변은 물론 해양까지 환경오염이 점점 심각해지고 있다. 그에 따른 재활용 시스템의 필요성이 높아지고 있으며, 지속 가능한 발전을 위해 세계적으로 환경을 위한 연구가 진행되고 있다. 본 논문에서는 딥러닝 기반의 AI 기술을 적극적으로 활용하여 분리수거가 아닌, 페트병을 재활용하는 과정을 집중적으로 개선한다. 이를 통하여, 페트병이 원인인 환경오염을 해결할 뿐만 아니라 고급 재활용 원료를 생산할 수 있게 하여 경제적인 효과도 얻을 수 있는 시스템을 제안한다.

• Journal of the Korean Society of Food Culture
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• v.27 no.6
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• pp.627-635
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• 2012

This study was conducted to investigate the preference for and recognition of Makgeolli by foreign students to determine its potential for export. From March 15 to 29, 2010, 300 students from four universities (Kyung-Hee University, Hankuk University of Foreign Studies, Yonsei University, Chung-Ang University) were surveyed and data from 287 subjects were used for subsequent analyses. The recognition of Makgeolli was as follows: 40.3% knew that Makgeolli's was fermented alcohol; 49.5% knew its proof; 85.7% knew that rice and wheat were the main ingredients of Makgeolli; 72.8% knew it was Korean traditional alcohol. The preference for Makgeolli's was as follows: flavor (3.46), color (3.43), aroma (3.30), texture (3.28), reverberation (3.36), shape of glass (3.51) and Korean bar (3.72), which were slightly high. However, hangover (3.02) and plastic bottle (3.08) had lower values than the other variables. Overall, participants were likely to recommend Makgeolli to others (Male 3.57, Female 3.72), but they did not think that it is a good ingredient for food (2.91). The opportunity for the globalization of Makgeolli appeared to be high (Male 3.57, Female 3.74). To improve the export of Makgoelli, respondents reported that a better marketing strategy (37%) and new type of bottle (42.8%) were needed.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.334-338
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• 2005

Method was developed to efficiently analyze semicarbazide (SEM) in foods. Although SEM is produced by thermal decomposition of blowing agent azodicarbonamide, it is too small to be activated by ultraviolet light or fluorescence. When 2-nitrobenzaldehyde semicarbazone, derivatization of SEM, was analyzed by HPLC with triple column system, coefficient correlation over 0.9997 and detection limit of 0.48 ng/g were observed. SEM level in commercial bottle cap gasket was 812.20-5771.30ng/g. Recoveries for SEM in food and PVC gasket were 83.45-97.33% and 92.12-98.71%, respectively. SEM level in plastic seals of press twist-off metal lids was ND-5771.330ng/g.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.231-234
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• 2011

This study was performed to develop new Hypsizygus marmoreus cultivars that have enhanced functional materials and improved physiological characteristics with mutagenesis by gamma ray irradiation. Protoplasts of H. marmoreus brown strain HYM-056 were irradiated by gamma ray for mutagenesis, and then 2,000 clones of mutants were randomly selected and the fruiting bodies were induced by bottle culture. Among them, 157 isolates with fast-growing, heavy and many fruiting body-producing were selected. The isolates were cultured in plastic bottle containing rice bran, barley hulls and fir sawdust to form the fruiting bodies. About 100 days after inoculation, characteristic of fruiting bodies were investigated. The isolates were divided into 6 groups based on color, shape and size of pileus, and length, diameter, number and weight of stipe. In addition, the genetic variation of the isolates was analyzed by URP-PCR fingerprinting.