• Journal of Christian Education in Korea
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• v.66
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• pp.309-341
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• 2021

The purpose of this study is to develop an intelligent learning platform model for faith education in preparation for the post-corona era. This study reviewed artificial intelligence algorithms, research on learning platform development, and prior research related to faith education. The draft of the intelligent learning platform design model was developed by synthesizing previous studies. The developed draft model was validated by a Delphi survey targeting 5 experts. The content validity of the developed draft model was all 1. This is the validation of the draft model. Three revised opinions of experts were presented on the model. And the model was revised to reflect the opinions of experts. The modified final model consisted of three areas: learning materials, learning activities, learning data, and artificial intelligence. Each area is composed of 9 elements of curriculum, learning content additional learning resources, learner type, learning behavior, evaluation behavior, learner characteristic data, learning activity data, artificial intelligence data, and learning analysis. Each component has 29 sub-elements. In addition, 14 learning floors were formed. The biggest implication of this study is the first development of a basic model of an intelligent learning platform for faith education.

• Membrane Journal
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• v.32 no.5
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• pp.292-303
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• 2022

An eco-friendly energy conversion device without the emission of pollutants has gained much attention due to the rapid use of fossil fuels inducing carbon dioxide emissions ever since the first industrial revolution in the 18th century. Polymer electrolyte membrane fuel cells (PEMFCs) that can produce water during the reaction without the emission of carbon dioxide are promising devices for automotive and residential applications. As a key component of PEMFCs, polymer electrolyte membranes (PEMs) need to have high proton conductivity and physicochemical stability during the operation. Currently, perfluorinated sulfonic acid-based PEMs (PFSA-PEMs) have been commercialized and utilized in PEMFC systems. Although the PFSA-PEMs are found to meet these criteria, there is an ongoing need to improve these further, to be useful in practical PEMFC operation. In addition, the well-known drawbacks of PFSA-PEMs including low glass transition temperature and high gas crossover need to be improved. Therefore, this review focused on recent trends in the development of high-performance PFSA-PEMs in three different ways. First, control of the side chain of PFSA copolymers can effectively improve the proton conductivity and thermal stability by increasing the ion exchange capacity and polymer crystallinity. Second, the development of composite-type PFSA-PEMs is an effective way to improve proton conductivity and physical stability by incorporating organic/inorganic additives. Finally, the incorporation of porous substrates is also a promising way to develop a thin pore-filling membrane showing low membrane resistance and outstanding durability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.84-88
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• 1984

To obtain basic information on the breeding of early maturing, short plant height rapeseed varieties, the following 7 varieties, Isuzu, Miyuki, Norin 25, Rang, Yongdang, Cresus and Tower were used in diallel crosses in 1979. Maturing date, plant height and grain weight per plant for the parents, $F_1$'s and $F_2$'s of the 7 x 7 partial diallel crosses were measured in 1981 for analysis of their genetic behavior. The results obtained are summarized as follows: 1. The days to maturing of $F_1$'s showed complete dominance for early maturing, and both additive and dominance genetic variances were significant. Number of effective factors in $F_1$'s was 3, but in $F_2$'s was 1. The degree of dominance in $F_1$'s was partial, while in $F_2$'s was complete. Both broad and narrow sense herita-bilities in $F_1$'s was high, while in $F_2$'s was low. 2. Yield per plant in $F_2$'s was controlled by additive component of genetic variance only, but $F_1$'s was different. The degree of dominance in $F_1$'s was complete, while in $F_2$'s was partial. The direction of dominance showed almost complete dominance over high yield and three effective factors was estimated. Yield per plant was controlled by recessive genes. 3. The plant height was controlled by both dominance and additive variance. Dominance was directed toward tall plant height. Number of effective factors was 2, and broad and narrow sense heritability were high in the plant height.

• Membrane Journal
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• v.32 no.6
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• pp.427-441
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• 2022

Polymer electrolyte membrane (PEM) serving as a separator that can prevent the permeation of unreacted fuels as well as an electrolyte that selectively transports protons from the anode to the cathode has been considered a key component of polymer electrolyte membrane fuel cell (PEMFC). The perfluorinated sulfonic acid-based PEMs, represented by Nafion®, have been commercialized in PEMFC systems due to their high proton conductivity and chemical stability. Nevertheless, these PEMs have several inherent drawbacks including high manufacturing costs by the complex synthetic processes and environmental problems caused by producing the toxic gases. Although numerous studies are underway to address these drawbacks including the development of sulfonated hydrocarbon polymer-based PEMs (SHP-PEMs), which can easily control the polymer structures, further improvement of PEM performances and durability is necessary for practical PEMFC applications. Therefore, this study focused on the various strategies for the development of SHP-PEMs with outstanding performance and durability by 1) introducing cross-linked structures, 2) incorporating organic/inorganic composites, and 3) fabricating reinforced-composite membranes using porous substrates.

• Journal of the Korean institute of surface engineering
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• v.56 no.6
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• pp.412-419
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• 2023

Anion exchange membrane electrolysis is considered a promising next-generation hydrogen production technology that can produce low-cost, clean hydrogen. However, anion exchange membrane electrolysis technology is in its early stages of development and requires intensive research on electrodes, which are a key component of the catalyst-system interface. In this study, we optimized the pressure conditions of the hot-pressing process to manufacture cobalt oxide electrodes for the development of a high uniformity and high adhesion electrode production process for the oxygen evolution reaction. As the pressure increased, the reduction of pores within the electrode and increased densification of catalytic particles led to the formation of a uniform electrode surface. The cobalt oxide electrode optimized for pressure conditions exhibited improved catalytic activity and durability. The optimized electrode was used as the anode in an AEMWE single cell, exhibiting a current density of 1.53 A cm^-2 at a cell voltage of 1.85 V. In a durability test conducted for 100 h at a constant current density of 500 mA cm^-2, it demonstrated excellent durability with a low degradation rate of 15.9 mV kh^-1, maintaining 99% of its initial performance.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.484-491
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• 2023

Maize is one of the major crops consumed in worldwide, which nutrients accounts for a large amount of starch, but also functional components, and phenolic acid is known to have a high content. Maize is divided into waxy maize, sweet maize, and normal maize with its shape and use, therefore there is also a difference in nutritional composition. This study was conducted to analyze the content of functional components according to the type of maize and to produce natural variation data in consideration of environmental factors. 3 shapes of maize (waxy maize, sweet maize, and normal maize) samples cultivated in 3 regions (Suwon, Daegu, and Hongcheon) were analyzed using HPLC and GC-TOF-MS. Comparing with type through ANOVA, multivariate statistical analysis, Pearson correlation analysis, 28 components, including carotenoids and tocopherols, showed significant differences among a total of 32 components (p <0.05), 15 of them showed very significant differences (p <0.001). When comparing with regions, 15 components showed significant differences and only vanillate, syringate, C23-ol of them showed most significant differences (p <0.001). As a result of principal component analysis, cluster classification was distinguished by shape than by region, with α-carotene, cholesterol for waxy maize, vanillate and stigmasterol for sweet maize, lutein and β-carotene for normal maize had a great effect on cluster formation. It suggests that the content of functional components is more affected by genetic factors than environmental factors.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.149-160
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• 2016

Temperature-dependent development and fecundity of apterious Rhopalosiphum padi (L.) (Hemiptera: Aphididae) were examined at six constant temperatures (10, 15, 20, 25, 30 and $35{\pm}1.0^{\circ}C$, RH 50-70%, 16L:8D). Development time of nymphs decreased with increasing temperature and ranged from 42.9 days at $10^{\circ}C$ to 4.7 days at $30^{\circ}C$. The nymphs did not develop until adult at $35^{\circ}C$ because the nymphs died during the 2nd instar. The lower threshold temperature and thermal constant of nymph were estimated as $8.3^{\circ}C$ and 101.6 degree days, respectively. The relationships between development rates of nymph and temperatures were well described by the nonlinear model of Lactin 2. The distribution of development times of each stage was successfully fitted to the Weibull function. The longevity of apterious adults decreased with increasing temperature ranging from 24.0 days at $15^{\circ}C$ to 4.3 days at $30^{\circ}C$, with abnormally short longevity of 11.1 days at $10^{\circ}C$. R. padi showed the highest fecundity at $20^{\circ}C$ (38.2) and the lowest fecundity at $10^{\circ}C$ (3.9). In this study, we provided component sub-models for the oviposition model of R. padi: total fecundity, age-specific cumulative oviposition rate, and age-specific survival rate as well as adult aging rate based on the adult physiological age.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.3
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• pp.13-21
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• 2017

This study was carried out to evaluate the application effects of fish meal liquid fertilizer on soil characteristics and growth of cucumber for organic cultivation. Cucumber in greenhouse was transplanted on March $31^{th}$ in 2016, and the experimental treatments involve six treatments: No fertilizer, 0, 25, 50, and 100 mg/L N application by fish meal liquid fertilizer and chemical fertilizer. In the results of soil chemical property, application of 100 mg/L of fish meal liquid fertilizer showed a significant differences in pH, K, and Mg contents. The soil microbial community varied in relation to the fish meal liquid fertilizer treatments. Microbial biomass was lower in the chemical fertilizer than in the liquid fertilizer treatment. Result of principal component analysis obtained from Ecoplate showed that fish meal liquid fertilizer treatments, no liquid fertilizer, chemical fertilizer, and no fertilizer were divided into distinct groups, with the no fertilizer treatment located furthest from the other treatments. There were no significant differences in plant height of cucumber between the fish meal liquid fertilizer treatments and chemical fertilizer treatments. Also, the cucumber yield did not vary significantly between the concentrations of liquid fertilizers, and there were also no significant differences in the yield among the fish meal liquid and chemical fertilizer treatments. In conclusion, it is suggested that the application of fish meal liquid fertilizer can be used as a additional fertilizer for cucumber production with organic culture in greenhouse.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1223-1230
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• 2008

To evaluate the potential of a new breed, Suweon-511, antioxidant components and antioxidant activities of the 70% ethanol extracts of Suweon-511 (SWE) and Ilpum (IPE) were measured. Total polyphenol and flavonoid contents were 318.17 and 167.21 $\mu$g/g for SWE, which were higher than that of IPE (222.16 and 100.89 $\mu$g/g). Both $\alpha$- and $\gamma$-tocopherol contents were higher in SWE as well. The total tocopherol contents of SWE (1.31 mg/100 g) was higher than that of IPE (0.86 mg/100 g). The $\alpha$-, $\gamma$- and $\delta$-tocotrienol contents of SWE (0.10, 0.43, and 0.02 mg/100 g) that of IPE (0.09, 0.43, and 0.03 mg/100 g) showed little difference. For $\gamma$-oryzanol, Suweon-511, which contained 76.58 $\mu$g/g, contained ten times as much as I lpum (7.77 $\mu$g/g). The total antioxidant activity of SWE and IPE were 16.00 and 9.73 mg AA eq/g, respectively. For reducing power, at 5 mg/mL, both extracts were 0.18, but at 20 mg/mL, SWE showed 0.61 and that of IPE was 0.58. The DPPH radical, hydroxyl radical, superoxide radical and hydrogen peroxide scavenging activity of SWE were 42.00, 21.59, 23.27, and 17.13% at 5 mg/mL, and for IPE, they were 30.10, 22.37, 25.18, and 18.08%, respectively. These data, as well, did not show big difference between the two breeds. As indicated in the data above, the newly-bred Suweon-511 had higher content of antioxidant components compared to Ilpum, but similar or a little higher antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1088-1094
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• 2014

This study investigated the quality properties of glutinous rice Gochujang produced by regional rural families in order to determine the present state of quality of traditional Gochujang. A total of 80 Gochujang samples were collected from nationwide rural families and their physicochemical characteristics were analyzed. Based on regional mean, ranges of moisture contents, pH, acidity, crude protein contents, and salinity of Gochujang were $44.31{\pm}5.73%{\sim}50.50{\pm}5.65%$, $4.59{\pm}0.36{\sim}4.79{\pm}0.15$, $1.18{\pm}0.22%{\sim}1.54{\pm}0.36%$, $5.28{\pm}0.90%{\sim}6.93{\pm}.09%$, and $5.55{\pm}0.85%{\sim}8.29{\pm}1.19%$, respectively. The mean contents of amino type N, reducing sugars, and capsaicinoids were $488.81{\pm}79.74mg%{\sim}715.16{\pm}78.09mg%$, $22.32{\pm}9.43%{\sim}28.61{\pm}8.80%$, and $44.31{\pm}18.71mg/kg{\sim}65.15{\pm}47.98mg/kg$, respectively, and differences were significant among the Gochujang samples. Hunter color values (L, a, and b) of Gochujang were $4.84{\pm}3.08$, $21.26{\pm}10.53$, and $8.20{\pm}5.91$, respectively, and the range of viscosity was $31,511{\pm}11,764{\sim}72,923{\pm}32,555$ cP. The acidity, salinity, moisture, crude protein, and amino type N contents of Gochujang produced from the Gangwon-do and Gyeonggi-do areas were significantly higher than those of other regions. According to principal component analysis of the physicochemical characteristics of Gochujang produced by rural families, the salinity, acidity, moisture, crude protein, and amino type N contents were strong characteristics of Gochujang produced by Gangwon-do and Gyeonggi-do. These results indicate that traditional Gochujang produced by rural families shows various quality properties and regional differences in physicochemical characteristics.