• Journal of Wetlands Research
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• v.25 no.1
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• pp.35-47
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• 2023

Korean facility horticulture and hydroponic cultivation methods increase, requiring the management of waste water generated. In this study, the amount of fertilizer contained in the discharged waste liquid was determined. By evaluating this as a price, it was suggested to reduce water treatment costs and recycle fertilizer components. It was evaluated based on the results of major water quality analysis of waste liquid by crop, such as tomatoes, paprika, cucumbers, and strawberries, and in the case of P component, it was analyzed by converting it to the amount of phosphoric acid (P₂O₅). The amount of nitrogen (N) can be calculated by discharging 1,145.90kg·ha^-1 of tomatoes, 920.43kg·ha^-1 of paprika, 804.16kg·ha^-1 of cucumbers, 405.83kg·ha^-1 of strawberries, and the fertilizer content of P₂O₅ is 830.65kg·ha^-1 of paprika, 622.32kg·ha^-1 of tomatoes, 477.67kg·ha^-1 of cucumbers. In addition, trace elements such as potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), and manganese (Mn) were also analyzed to be emitted. The price per kg of each item calculated by averaging the price of fertilizer sold on the market can be evaluated as KRW, N 860.7, P 2,378.2, K 2,121.7, Ca 981.2, Mg 1,036.3, Fe 126,076.9, Mn 62,322.1, Zn 15,825.0, Cu 31,362.0, B 4,238.0, Mo 149,041.7. The annual fertilizer loss amount for each crop was calculated by comprehensively considering the price per kg calculated based on the market price of fertilizer, the concentration of waste by crop analyzed earlier, and the average annual emission of hydroponic cultivation. As a result of the analysis, the average of the four hydroponic crops was 5,475,361.1 won in fertilizer ingredients, with tomatoes valued at 6,995,622.3 won, paprika valued at 7,384,923.8 won, cucumbers valued at 5,091,607.9 won, and strawberries valued at 2,429,290.6 won. It was expected that if hydroponic drainage is managed through self-treatment or threshing before discharge rather than by leaking it into a river and treating it as a pollutant, it can be a valuable reusable fertilizer ingredient along with reducing water treatment costs.

• Science of Emotion and Sensibility
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• v.21 no.2
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• pp.101-112
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• 2018

This study was carried out to enhance the competitiveness of blackbox design for domestic and international companies, based on the explosive growth of the blackbox market due to development of blackbox design for vehicle accident prevention and post-treatment. In the past, the blackbox market has produced products indiscriminately to meet the ever-increasing demand of consumers. Therefore, we thought a new design method was necessary to effectively investigate the needs of rapidly changing consumers. In this study, we aimed to identify the best-selling blackbox to understand the design flow, and the optimum area for a blackbox, considering the uniqueness of associated vehicle. Based on discussion with blackbox design experts, we studied the direction of design and the problems with blackbox use, which were reflected in blackbox development. Through this research, two types of design - leading blackbox (A type) and mass production blackbox (B type) - were proposed for compatibility of the blackbox with the car. The leading type of blackbox was positioned so that it was wrapped with the room mirror hinge before the screw was fastened, in order to achieve an integrated design. Therefore, we designed an integrated form and resolved the placement problem of an adhesive blackbox. To blend, the mass production blackbox implemented material and surface processing in the same way with the car, and adopted the slide structure to automatically turn off the main body power when removing the SDcard, reflecting consumer needs. This study considers evolving consumer needs through a case study and collective intelligence and deals with implementation of the whole design process during mass production. In this study, we aimed to strengthen the competitiveness of the blackbox design based on design method and its realization.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.178-183
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• 2017

This study examined a new functional cosmetic material possessing application possibility of Sambucus sieboldiana var. pendula (Nakai) (SS) extract. For this, we analyzed the toxic effect of the SS extract on macrophages (RAW 264.7 cells) by performing MTT assay. Results of the MTT assay showed ${\geq}100%$ cell viability after treatment with $500{\mu}g/ml$ SS extract. To determine the anti-inflammatory activity of the SS extract, we examined its inhibitory effect on lipopolysaccharide (LPS)-induced NO production in RAW 264.7 cells by performing Griess assay. Result of the Griess assay showed that the SS extract inhibited LPS-induced NO production in a concentration-dependent manner. Next, we examined the effect of the SS extract on the production of proinflammatory factors inducible NOS (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 cells. First, we determined the inhibitory effect of 50, 100, and $500{\mu}g/ml$ SS extract on iNOS and COX-2 protein expression by performing western blot analysis, with ${\beta}$-actin as a positive control. Results of western blotting showed that treatment with $500{\mu}g/ml$ SS extract decreased iNOS and COX-2 protein expression by 31.2% and 54.7%, respectively. Next, we determined the inhibitory effect of 50, 100, and $500{\mu}g/ml$ SS extract on iNOS and COX-2 mRNA expression by performing reverse transcription-polymerase chain reaction (PCR), with GAPDH as a positive control. Results of reverse transcription-PCR showed that treatment with $500{\mu}g/ml$ SS extract decreased the mRNA expression of iNOS and COX-2 by 72.2% and 89%, respectively. These results suggest that the SS extract is a highly valuable natural compound because of its functional components and anti-inflammatory activity.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.468-474
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• 2010

Alcoholic fermentations with rice koji [Aspergillus awamori Nakazawa KCCM 60246 (black), Aspergillus kawachii KCCM 32819 (white), Aspergillus oryzae KCCM 11372 (yellow)] and improved nuruk were carried out for the preparation of sweet potato soju using two different potato cultivars (Jinhongmi and Hobak). The Jinhongmi mashes showed $9.2-11.4^{\circ}Brix$, 195.6-260.5 mg glucose/100 mL, pH 4.6-4.9, 0.53-0.83% acidity and 13.2-16.2% alcohol content. The Hobak mashes showed $7.0-8.4^{\circ}Brix$, 31.9-47.4 mg glucose/100 mL, pH 4.4-4.7, 0.22-0.24% acidity, and 9.6-11.2% alcohol content. The alcohol yield of the Jinhongmi mashes using black, white, yellow koji and improved nuruk were 229.2, 194.5, 238.6 and 229.3 L/ton, respectively. The alcohol yields of Hobak mashes using black, white, yellow koji and improved nuruk were 132.8, 144.4, 141.6 and 167.4 L/ton, respectively. All types of sweet potato soju showed stronger flavor and taste than Kurokirishima (Japanese sweet potato soju). Especially, soju made from Jinhongmi with white koji and Jinhongmi with improved nuruk showed the strongest levels. Flavor components of sweet potato soju included decanoic acid ethylester, dodecanoic acid ethylester, tetradecanoic acid ethylester, hexadecanoic acid ethylester, 9-octadecanoic acid ethylester, and octadecanoic acid ethylester. Although the flavor profiles of Jinhongmi soju, Hobak soju, and Kurokirishima were very similar, the flavor content of Kurokirishima soju was lower. The results of the GC volatile analysis were in good correlation with flavor and taste.

• Journal of The Korean Association For Science Education
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• v.38 no.5
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• pp.611-623
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• 2018

This study investigated verbal behaviors and interactions in the processes of making written test items using paired think aloud problem solving for pre-service secondary chemistry teachers. The processes of making written test items using paired think-aloud problem solving in four small groups consisting of two pre-service chemistry teachers were recorded and transcribed. The analysis of the results revealed that 'item making' for ten subcategories for solver's verbal behaviors were most frequently exhibited regardless of 'integration' among the components of pedagogical content knowledge (PCK). The solver's 'provide', 'modify', 'require agreement', 'ask', 'agree', and 'justify' were also frequently exhibited although fewer than 'item making'. Especially, the solver's 'ask' was more frequently used in 'non-integration', whereas 'justify' was more frequently used in 'integration'. In listener's verbal behaviors consisted of eight subcategories, 'point out', 'ask', and 'agree' were frequently exhibited regardless of 'integration'. Listener's 'ask' and 'agree' were exhibited more in 'non-integration', whereas 'point out' was exhibited more in 'integration'. Many verbal interactions were analyzed to be in 'symmetrical type' more than 'solver-dominant type' or 'listener-dominant type'. 'Symmetrical type' was also more frequently exhibited in 'integration', whereas 'solver-dominant type' was more frequently exhibited in 'non-integration'. There were little differences between 'integration' and 'non-integration' in 'listener-dominant type'. In 23 subcategories of 'symmetrical type', 'ask-provide' and 'point out-justify' were most frequently found. Especially, 'ask-provide' was more frequently found in 'non-integration', whereas 'point out-justify' was more frequently found in 'integration'. 'Point out-modify' was the most frequent in 4 subcategories of 'listener-dominant type', while 'item making-agree' in three subcategories of 'solver-dominant type' regardless of 'integration'. However, only a little of other subcategories of the three types were found.

• Journal of Life Science
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• v.28 no.11
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• pp.1339-1346
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• 2018

In Korea, edible mushrooms are produced largely on commercial artificial media, so the annual production of spent mushroom substrate (SMS), as a by-product of the mushroom industry, is estimated at over 200 million tons. This SMS is assumed to contain abundant fungal mycelia and pre-fruiting bodies, as well as various nutritive and bioactive compounds that are presently discarded. This study examined the physico-chemical, nutritional, and enzymatic characteristics of uninoculated sterilized medium (USM) and SMS of shiitake mushrooms with the aim of developing a high-value added product from SMS. The contents of crude protein, crude lipid, and ash were higher after the third SMS harvest ($SMS-A-3^{rd}$) than in USM or $SMS-A-1^{st}$. The contents of Ca, Mg, and P in $SMS-A-3^{rd}$ were 2.95, 2.35, and 2.1-fold higher compared than in USM. No As or Cd was detected in USM or SMS. The pH, Brix, and acidity were 4.6, 20.0, and 1.4, respectively in $SMS-A-3^{rd}$, but 5.6, 6.0, and 0.0, respectively, in USM. These results suggest a highly active production of soluble components and organic acids in $SMS-A-3^{rd}$. The distinct color differences noted for USM, $SMS-A-1^{st}$, and $SMS-A-3^{rd}$ could be used as a mycelial growth indicator. Enzyme activity assays using the APIZYM system showed that SMS is a potent source of hydrolysis-related enzymes, especially esterase (C4) and ${\beta}$-glucuronidase. Our results suggested that the SMS of shiitake has a high potential for use in environmental, agricultural, and stock-breeding industries, for example, as active ingredients for sewage treatment, waste-polymer degradation, and feed additives.

• Resources Recycling
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• v.31 no.6
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• pp.44-51
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• 2022

In the steelmaking process using an electric arc furnace (EAF), light-burnt dolomite, which is a flux containing MgO, is used to protect refractory materials and improve desulfurization ability. Furthermore, a recarburizing agent is added to reduce energy consumption via slag foaming and to induce the deoxidation effect. Herein, a waste MgO-C based refractory material was used to achieve the aforementioned effects economically. The waste MgO-C refractory materials contain a significant amount of MgO and graphite components; however, most of these materials are currently discarded instead of being recycled. The mass recycling of waste MgO-C refractory materials would be achievable if their applicability as a flux for steelmaking is proven. Therefore, experiments were performed using a target composition range similar to the commercial EAF slag composition. A pre-melted base slag was prepared by mixing SiO₂, Al₂O₃, and FeO in an alumina crucible and heating at 1450℃ for 1 h or more. Subsequently, a mixed flux #2 (a mixture of light-burnt dolomite, waste MgO-C based refractory material, and limestone) was added to the prepared pre-melted base slag and a melting reaction test was performed. Injecting the pre-melted base slag with the flux facilitates the formation of the target EAF slag. These results were compared with that of mixed flux #1 (a mixture of light-burnt dolomite and limestone), which is a conventional steelmaking flux, and the possibility of replacement was evaluated. To obtain a reliable evaluation, characterization techniques like X-ray diffraction (XRD) analysis and X-ray fluorescence (XRF) spectrometry were used, and slag foam height, slag basicity, and Fe recovery were calculated.

• Analytical Science and Technology
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• v.27 no.1
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• pp.1-10
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• 2014

The $PM_{10}$ and $PM_{2.5}$ samples were collected at Gosan Site of Jeju Island, and analyzed, in order to investigate the size distribution and pollution characteristics of their components. $NH{_4}{^+}$, nss-$SO{_4}^{2-}$, $K^+$, and $CH_3COO^-$ were mostly existed in fine particles. Meanwhile, $NO{_3}{^-}$ was distributed in both fine and coarse particles, and $Na^+$, $Cl^-$, $Mg^{2+}$, nss-$Ca^{2+}$ were rich in coarse particle mode. The concentrations of nss-$Ca^{2+}$ and $NO{_3}{^-}$ were increased 36.7 and 3.2 times in coarse particles, and 15.0 and 3.1 times in fine particles during the Asian Dust periods. Especially, the concentrations of crustal elemental species such as Al, Fe, Ca, K, Mg, Ti, Mn, Sr, Ba were highly increased for those periods. In the haze events, the concentrations of secondary air pollutants were increased 1.3~2.6 and 1.5~4.2 times in coarse and fine particles, respectively. Moreover, the remarkable increase of $NO{_3}{^-}$ concentration was also observed in fine particle mode. The factor analysis showed that the composition of coarse particles was influenced mainly by marine sources, followed by soil and anthropogenic sources. On the other hand, the fine particles were influenced by anthropogenic sources, followed by marine and soil sources.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.97-104
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• 2018

The larva of the white-spotted flower chafer, Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae), is known to have important medicinal properties, such as anti-cancer activity. However, the consumer market for the larvae is depressed because of its high production cost which needs to be reduced. This study was carried out to evaluate two spent mushroom substrates as food source for chafer larvae to improve the productivity and reduce production cost. The larvae were fed with spent substrates of king oyster mushroom (Pleurotus eryngii) (P-SMS) and shiitake mushroom (Lentinula edodes) (L-SMS), with a control of fermented oak sawdust. Effects of the diets on the development of P. brevitarsis seulensis and contents of minor nutrient components in the larvae produced were examined. In the P-SMS diet, the larval rearing period was shorter at 16.2 days, while the rate of larval weight gain and the cocoon weight were higher at 156.3% and 4.1 g, respectively, than that in the L-SMS diet. The pupation rate was 100% and the adult emergence was higher at 93.3% in the P-SMS diet than in the L-SMS diet with no difference to the control diet. In the P-SMS diet, the total nitrogen content during rearing was higher at 10.28% and the minor nutrient component, particularly Fe (145.8 mg/kg), was higher than that in other diets. The oviposition preference of adults showed no significant difference among the diets. Economic analysis showed that P-SMS costs approximately 667,960 Won less per 100 kg of larvae produced, compared to that of the control diet.

• Journal of The Korean Association For Science Education
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• v.22 no.4
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• pp.779-795
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• 2002

Internet, a world wide network of computers, is considered as a sea of information because it allows people to share information beyond the barriors of time and space. However, in spite of the unmeasurable potential applications of the internet, its use in the field of biology education has been extremely limited mainly due to the scarcity of good biology-related sites. In order to provide useful guidelines for constructing user-friendly study sites, which can help high school students with different intellectual levels to study biology, comparative studies were performed on selected educational sites. Initially, hundreds of related sites were examined, and, subsequently, four distinct sites were selected not only because they are well organized, but also because each is unique in its contents. Also, a survey was carried out against the users of each site. The survey results indicated that the high school students regard the web-based biology study tools as effective teaching methods although there might be some bias in criteria for selecting target sites. In addition to the detailed biology topics and the related biology informations, multimedia data including pictures, animations and movies are found to be one of the important ingredients for desirable biology study sites. Thus, the inclusion of multimedia components should also be considered when developing a systematic biology study site. Overall, the role of the cyber space is expected to become more and more important. Since the development of the user-satisfied and self-guided sites require interdisciplinary collaborational efforts which should be made to promote extensive communication among teachers, education professionals, and computer engineers. Furthermore, the introduction of good biology study sites to the students by their teachers is also important factor for the successful web-based education.