• Advances in concrete construction
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• v.10 no.5
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• pp.403-416
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• 2020

This study investigated the effect of alkaline activators - NaOH_aq (NH) (NH: 0-16 M) and Na₂SiO_3aq (NS) (NS/NH: 0-3.5) in the synthesis of silico-manganese fume (SMF) and ground blast furnace slag (BFS) blended alkali-activated mortar (AASB). The use of individual activator was ineffective in producing AASB of sufficient fresh and hardened properties, compared to the synergy of both activators. This may be attributed to incomplete dissolution and condensation of oligomers required for gelation of the binder. An inverse relationship was noted among the fresh properties and the NH concentration or NS/NH ratio. This was influenced by the dissolution and condensation of silicate monomers under polymerization process. The maximum 28-day strength of ~45 MPa, setting time of 60 min and flow of 182 mm was obtained with the use of combined activators (10M-NH and NS/NH=2.5). The combined activators at NS/10M-NH=2.5 constituted SiO₂/Na₂O, H₂O/Na₂O and H₂O/SiO₂ molar ratio of 1.61, 17.33 and 10.77, respectively. This facilitated the formation of C-S-H, C/K-A-S-H and C-Mn-S-H in the framework together with an increase in the crystallinity due to more silicate re-organization within the aluminosilicate chain. On comparison of the high concentrated with mild alkali synthesized product, it revealed that the concentration of OH^- and Si monomers together with alkali metals influenced the dissolution of precursors and embedment of the constituent elements in the polymeric matrix. These factors eventually contributed to the microstructural densification of the mortar prepared with NS/10M-NH=2.5 thereby enhancing the compressive strength.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.381-392
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• 2020

This study is purposed to check up the natural 12 kinds of herbal extracts suitable for hangover and based on the results of contents of phenolic compounds, ABTS radical scavenging activity, alcohol dehydrogenase (ADH), and acetaldehyde dehydrogenase (ALDH). Selected 8 kinds of herbal extracts are blended according to the efficacy and the pearson's correlation between each content and activity. C. sinensis var. sinensis, P. densiflora Gnarl and P. lobata Ohwi showed excellent ADH activity, P. lobata Ohwi had a strong correlation between the content and efficacy, and C. sinensis var. sinensis, P. densiflora Gnarl had a negative correlation. Through the ADH and ALDH activity test of F.1 to F.7, the F.7 showed the highest synergic effect and selected as an optimal formulation. F.7 intake-group, the breath alcohol concentration was significantly reduced to 58% after 30 minutes and 27% after 120 minutes, compared to right after alcohol consumption. After alcohol consumption, there was a significant improvement effect (p<0.05) in tired and thirst in the intake group compared to the non-intake group.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.632-637
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• 2017

The vehicle lubricant occupies upto 35% in a total lubricant market and engine oil occupies upto 77% in the vehicle lubricant market in Korea. A suitable quality management of the circulating engine oil is necessary for driver and engine protection. But, KS and synthetic engine oil products (involved over 30% synthetic oil) are exempt to any quality management under Petroleum and Alternative Fuel Business Act. It is also known that synthetic oils such as PAO (poly alpha olefin) have excellent properties and performance like anti-wear, varnish control and oxidation stability than those of mineral oils. For this reason, PAO has been used for an engine oil, rotary screw and reciprocating compressor in addition to heavy duty and other extreme service applications. In this study, our research group analyzed the chromatogram pattern for the mineral oil, PAO and mineral oil involved a typical ratio of PAO using SIMDIST (simulated distillation). In the SIMDIST chromatogram, the mineral oil showed a broad peak, while PAO showed a sharp typical peak. Also the oil with a large viscosity grade exhibited a long retention time due to the heavy molecular weight and high boiling point. In particular, the blended mineral oil with 20% PAO sample showed a distinctly different pattern compared to that of using the conventional mineral oil. For monitoring PAO contents in distributing engine oils, we analyzed the SIMDIST for 27 kinds of engine oils which were popularly sold in Korea. The analytic results indicate that all kinds of engine oils showed that PAO contents were below 20% in engine oil products. Moreover, the PAO titled product was found to have a small amount of PAO. Thus, we conclude that the related laws for the proper quality management of synthetic oils are needed to be established.

• Journal of the Korea Concrete Institute
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• v.21 no.5
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• pp.565-572
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• 2009

In this study, corrosion resistance of palm oil fuel ash (POFA) concrete as a blended concrete is evaluated by using electrochemical technique. The POFA is an industrial byproduct obtained from fuel ash after extracting palm oil from palm-tree. In order to obtain basic material characteristics of the POFA concrete, tests on compressive strength, slump, weight loss, bleeding and expansion ratio were carried out the early-aged POFA concrete. On the other hand, durability characteristics, both chloride penetration and carbonation depth test, were also conducted. Finally, corrosion resistance were evaluated by applying electro-chemical artificial crack healing technique, and the tests on the impressed voltage characteristic, galvanic current and linear polarization resistance. From the experimental results, it was found that long-term strength, bleeding, lower slump ratio, expansion ratio, chloride penetration, carbonation and corrosion resistance were improved by using the POFA due to activated pozzolanic reaction. It can be also mentioned that POFA concrete has a potential to be used as a cementitious binder for green-recycling resources.

• Cartoon and Animation Studies
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• s.43
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• pp.363-386
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• 2016

This research is to design basic framework for developing teaching and learning method in the field of art and design major in university. Especially taking off from oneway e-learning teaching method, it is focused on increasing reality of student learning situation with applying AR contents process to augment virtual condition on reality condition. The processing of framework design and developing teaching and learning method are about practice education based on AR for model experiment research which was published "The E-Learning for Practice Training Using Augmented Reality in the College Education". This thesis is supposed to be a precedent study of the pre-published, and the purpose of those two studies were for experiment test in earnest in studying effect research. The classification of learning method divided basically as Face-to-Face Learning(FFL), Blended Learning(BL), fully E-Learning(EL), and Augmented Reality based E-Learning(AREL). This research compares and analyzes each frame of FFL, BL, and EL. And then, designed framework lead to the over-all conclusion with the type of AREL. Additionally, AREL for PBE suggests the ways of advanced teaching learning.

• Membrane Journal
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• v.27 no.2
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• pp.147-153
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• 2017

In this study, we investigated permeation properties of single gas ($N_2$, $O_2$, $CO_2$) through membranes composed of poly(ethylene oxide) (PEO) and poly(ethylene-co-vinyl acetate) (EVA) blend. The prepared membranes showed no new absorbance peaks, which indicate the physical blending of PEO and EVA by FT-IR analysis. SEM observation showed that the crystalline phase of PEO decreased with increasing EVA content in the PEO/EVA mixed matrix. DSC analysis showed that the crystallinity of the PEO/EVA blend membrane decreased with increasing EVA content. Gas permeation experiment was performed with various feed pressure (4~8 bar). The permeability increased in the following order: $N_2$ < $O_2$ < $CO_2$. The permeability of $CO_2$ in PEO/EVA blend membranes were increased with increasing feed pressure, However, the permeability of $N_2$ and $O_2$ were independent of feed pressure. On the other hand, the permeability of all the gases in PEO/EVA blend membranes increased with increasing amorphous EVA content in semi-crystalline PEO. In particular, the blend membrane with 40 wt% EVA showed $CO_2$ permeability of 64 Barrer and $CO_2/N_2$ ideal selectivity of 61.5. The high $CO_2$ permeability and $CO_2/N_2$ ideal selectivity are attributed to strong affinity between the polar ether groups of PEO or the polar ester groups of EVA and polar $CO_2$.

• Membrane Journal
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• v.30 no.3
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• pp.190-199
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• 2020

The utilization of multiple water sources becomes important due to the master plan for development of water supply released by Ministry of Environment, Korea in 2018. In this study, therefore, the analysis of comprehensive effect in blending applicable water sources in Daesan where 100,000 ㎥/d seawater desalination plant will be constructed for industrial use was performed. The increase in mixing ratio of other water sources with seawater reduced salinity up to 50%, but negatively impacted the turbid and organic matter. Lab-scale reverse osmosis performance test also found that membrane fouling was exacerbated in blended water condition. The simulation results of reverse osmosis indicated 39% energy saving on average is expected at the one-to-one blending ratio, however, long-term performance test at the pilot-scale plant is highly required to evaluate the inclusive impact of mixing seawater and other water sources.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.351-359
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• 1991

Demand for the rice of better eating quality is ever increasing in recent years. However. the rice is presently handled by the government and merchants as mixture of the rice of different varieties from the purchase of the rough rice to storing and milling. It is well known that the eating quality of rice varies significantly by variety. The present study aimed at evaluation of the effect of blending different rices on the change in palatability of low and high eating quality rices. The eating quality of a low quality japonica rice was improved significantly on sensory panel test by blending it with the Dongjin rice. one of the highest eating quality. only when the Dongjin was blended to 80 percent by weight. and also it was same for blending an ordinary quality rice of mixed varieties which has been stored by a governmental storehouse with a top class rice on free market. The eating quality of aged Tongil type rice. produce of 1987 and 1989 and a mixture of varieties, was improved significantly by blending it with a high quality glutinous rice on market to 20 per cent by weight. But Samgang rice. a high eating quality Tongil type variety. and an ordinary quality rice of Japonica varieties were not significantly improved by blending them with the glutinous rice by 20 per cent. Blending rices of the variety Nagdong. ordinary quality among varieties and low quality among Japonicas, Chucheong, a high quality rice among Japonicas. and Dongjin. one of the best eating quality rice among Japonicas, each other in different ratios did not affect significantly the sensory scores.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.113-118
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• 2011

This study was aimed to develop blend films by rice by-product (rice-hull and rice-bran) and bio-degradable materials. The rice by-product was firstly prepared from the pulverizing for making fine powder. Bio-degradable materials could be prepared by melting at high temperature. The mixture of the fine powder of rice by-product and melted bio-degradable materials was then blended and cast into films. The obtained films were investigated on their morphology, secondary structures and properties by using SEM, ICP and ASTM, respectively. Mechanical properties and degradability of these films were measured and compared to those of the PE films. Mechanical strength of bio-films was higher than that of PE films, however elongation ratio showed lower percent than that of PE film. In addition, bio-film could be degraded into fragments within 3 months under the field condition of normal upland crop cultivation. Bio-degradable mulching film indicated great potential for agronomic use as a new source of bio-degradable material.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.660-666
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• 2008

This study was designed to compare the thermal oxidative stability of lard, soy bean oil, and hot pepper seed oil for 0-3 d at $100^{\circ}C$, and to evaluate the effect of capsaicin on thermal oxidative stability in lard and soy bean oil. As result, thermal oxidation stability was shown in the order hot pepper seed oil>soy bean oil>lard for 0-3 d at $100^{\circ}C$. In blended oils, hot pepper seed oil effectively inhibited lipid oxidation when mixed with lard than soy bean oil by showing the ratio of 30% pepper seed oil plus 70% lard and 60% pepper seed oil plus 40% soy bean oil inhibited lipid oxidation during storage periods. And to investigate the antioxidative effect of antioxidants such as capsaicin and alpha-tocopherol in hot pepper seed oil, 1,200 and 2,400 ppm capsaicin, or 0.3% alpha-tocopherol were added in soy bean oil and lard and stroed for 0-3 d at $100^{\circ}C$. Capsaicin inhibited lipid oxidation in lard but not in soy bean oil, however alpha-tocopherol exhibited a prooxidaton effect in soybean oil. Therefore, it suggests that the application of hot pepper seed oil or capsaicin in lard may be better for thermal oxidative stability.