• Journal of Korean Society of Water and Wastewater
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• v.35 no.4
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• pp.285-292
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• 2021

Osmotic power is to produce electric power by using the chemical potential of two flows with the difference of salinity. Water permeates through a semipermeable membrane from a low concentration feed solution to a high concentration draw solution due to osmotic pressure. In a pressure retarded osmosis (PRO) process, river water and wastewater are commonly used as low salinity feed solution, whereas seawater and brine from the SWRO plant are employed as draw solution. During the PRO process using wastewater effluent as feed solution, PRO membrane fouling is usually caused by the convective or diffusive transport of PRO which is the most critical step of PRO membrane in order to prevent membrane fouling. The main objective of this study is to assess the PRO membrane fouling reduction by pretreatment to remove organic matter using coagulation-UF membrane process. The experimental results obtained from the pretreatment test showed that the optimum ferric chloride and PAC dosage for removal of organic matter applied for the coagulation and adsorption process was 50 mg/L as FeCl₃ (optimum pH 5.5). Coagulation-UF pretreatment process was higher removal efficiency of organic matter, as also resulting in the substantial improvement of water flux of PRO membrane.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.2
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• pp.83-93
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• 2011

Biochemical and enzymatic characterization for extracellular protease isolated from Cordyceps militaris cultivated on rice bran medium was investigated. C militaris produced proteolytic enzymes from 10 days after inoculation, maximum enzyme production was found at 25 days. The optimum temperature and pH of proteases production was at $25^{\circ}C$ and pH 7.0, respectively. The protease activity was observed in the four peaks (Pro-I, Pro-II, Pro-III, and Pro-IV) separated through Sephadex G-100 column chromatography. The separated protease was optimally active at $25^{\circ}C$. Optimum pH of the protease was between 7 and 8. Enzyme was also stable over at $30-80^{\circ}C$. The enzyme was highly stable in a pH range of 4-9. Protease activity was found to be slightly decreased by the addition of $Mg^{2+}$, $Mn^{2+}$, $Zn^{2+}$, $Fe^{2+}$ and $Cu^{2+}$, whereas inhibited by the addition of $Ca^{2+}$ and $Co^{2+}$ Protease activity was inhibited by protease inhibitor PMSF. On the other hand, the partially purified protease was investigated on proteolytic protease activity by zymogram gel electrophoresis using three substances (casein, gelatin and fibrin). Four active bands (F-I, FII, F-III, and F-IV) of fibrin degradation were revealed on fibrin zymogram gels. Both of F-II and FIII showed caseinolytic, fibrinolytic and gelatinolytic activities in three gels. Thermostability, pH stability, and pH-thermostability of the enzyme determined the residual fibrinolytic activity also displayed on fibrin zymogram gel. The only one enzyme (F-II) displayed over a broad range of temperature at $30-90^{\circ}C$. The FII displayed fibrinolytic activity in the pH range 3-5, but was inactivated in the range of pH 6-11. The F-I and F-III showed enzyme activity in the pH range of 6-11. In the pH-thermostability, the F-II only kept fibrinolytic activity after heating at $100^{\circ}C$ for 10, 20 and 30 min at pH 3 and pH 7, respectively. On the other hand, the F-II was retained activity until heating for 10 min under pH 11 condition. By using fibrin zymogram gel electrophoresis, extracellular fibrinolytic enzyme F-II from C. militaris showed unusual thermostable under acid and neutral conditions.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.598-608
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• 2000

This study examined several characteristics such as the relationships between environmental attitudes and national park visitors' socio-economic characteristics, and between environmental attitudes and their travel motivations. Environmental attitude was measured using the modified New Environmental Paradigm(NEP) scale, where five response options existed(from strongly disagree to strongly agree). Data for this empirical analysis were obtained from 2,647 participants at six national parks-Sulaksan, Kayasan, Naeiangsan, Pookhansan, Taeanhaean, and Hanryohaesang. Results showed that most visitors gave a pro-NEP response ranging from neutral attitude to pro-environmentalism. Environmental attitudes correlated positively with education level, while, negatively with age. Environmental concern, also, generally correlated positively with 'rest' and 'health' motivators, while, negatively with 'socialization' and 'vacation' motivators. The findings of this study suggest that education is the most effective politic measure to lead pro-environmental concern for park visitors. And, given the nature of the relationship between environmental concern and visitors' motivation, park managers should be more careful handling with family and group visitors who have 'vacation' and 'socialization' motivators than 'rest' and 'health' motivators.

• Korean Institute of Interior Design Journal
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• no.1
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• pp.26-31
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• 1992

The purpose of this study was to determine the effect of a pleasantly designed interior inpro-spatial behavior. For pleasantly designed interior, the existing interior was remodeled through the change of finishing materials for major architectural elements such as wall, floor and ceiling, and changes of furniture and it's arrangement. Prospatial behavior was operationalized as seat arranging behavior and measured through the arranged condition and observable arranging behavior. Time-series design, one of quasi-experimental design was used. The data in this study were extracted from an existing field experimental research. One hundred forty four video tapes recorded during 6 months out of 2 years period ware used. In conclusion , the pro-spartial behavior change was a mid-term positive effect of pleasantly designed environment. In an environmental setting where pro-spatial behavior was most important, a certain time cycle to change the environment needs to be considered.

• Toxicological Research
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• v.25 no.4
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• pp.159-173
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• 2009

Nuclear factor erythroid derived 2-related factor-2 (Nrf2) is a master transcription regulator of antioxidant and cytoprotective proteins that mediate cellular defense against oxidative and inflammatory stresses. Disruption of cellular stress response by Nrf2 deficiency causes enhanced susceptibility to infection and related inflammatory diseases as a consequence of exacerbated immune-mediated hypersensitivity and autoimmunity. The cellular defense capacity potentiated by Nrf2 activation appears to balance the population of $CD4^+$ and $CD8^+$ of lymph node cells for proper innate immune responses. Nrf2 can negatively regulate the activation of pro-inflammatory signaling molecules such as p38 MAPK, NF-${\kappa}B$, and AP-1. Nrf2 subsequently functions to inhibit the production of pro-inflammatory mediators including cytokines, chemokines, cell adhesion molecules, matrix metalloproteinases, COX-2 and iNOS. Although not clearly elucidated, the antioxidative function of genes targeted by Nrf2 may cooperatively regulate the innate immune response and also repress the expression of pro-inflammatory mediators.

• Journal of the Korean Home Economics Association
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• v.40 no.2
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• pp.39-56
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• 2002

The purpose of this study was to review criticallu the current slates of researches in the area of consumer culture and to suggest several ways in which it can be improved. After analyzing 87 articles in major journals which have published during the 1980s, 1990s, the major findings are as follows: First, the articles in this field has increased sharply in latter half of 1990s. Second, the subjects of these researches can be divided into three. They are general consumption culture(including consumption value), abnormal consumer behavior(including overconsumption, addictive buying and conspicuous consumption) and pro-environmental consumer behavior. Third, the adolescents is most frequently researched. Fourth, same as other areas the major methodology is positivistic one which focuses the survey analysis to investigate the relationships of many variables. Implications are also discussed with respect to future research.

• Environmental Mutagens and Carcinogens
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• v.25 no.2
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• pp.71-75
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• 2005

Green tea and their major constituents such as catechins are famous materials for their anti-oxidative and anti-carcinogenic activity, but many compounds with reducing power can promote the oxidation in their oxidized form or in the presence of metal ion. We investigated the pro-oxidative effect of the ethanol extract equivalent up to 30mg of dried weight of green tea leaves in four in vitro systems which could be used for detecting DNA damage. Although ethanol extract of green tea did not show significant mutagenicity in Salmonella typhimurium TA102, which is sensitive strain to oxidative stress, it degraded deoxyribose extensively in the presence of $FeCl_3-EDTA$ complex, promoted 8-oxoguanine formation in the live bacteria cell, Salmonella typhimurium TAI04, and cleaved super coiled DNA strand with the help of copper ion. It suggested that green tea, famous anti-oxidative material, can be pro-oxidant according to the condition of extraction or metal existence.

• Membrane Journal
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• v.25 no.4
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• pp.367-372
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• 2015

In pressure-retarded osmosis (PRO) and forward osmosis (FO) processes, solvent (permeate) flux depends on which surface the draw solution faces. There are two operation modes. PRO mode indicates that the active layer faces the draw solution, and FO mode means that the porous substrate fronts the draw stream. It is often observed that the PRO mode produces higher flux than that of FO under the same operating conditions. The current work uses the method of proof by contradiction, and mathematically proves the intrinsic flux inequality between the two modes.

• Proceedings of KHEA Conference
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• 1997.07a
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• pp.86-86
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• 1997

• Journal of Families and Better Life
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• v.25 no.2 s.86
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• pp.23-36
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• 2007

Or this research, it was investigated the differences in the pro-environmental behaviors in purchase, use and management, and disposal of clothing by socio-demographic characteristics and other variables. In addition, it was classified Korean consumers into several comsumer groups based on the different purchase behavior style, and then investigated the difference among these consumer groups in purchase, use and management, and disposal of clothing in light of the pro-environmental behavior. The following is the summary of the main results. First, consumers with high income and ha41g a lot of clothing were less likely to purchase used-clothing while consumers who were non-married and in low-income status were more likely to rent clothing. In additions, female, married consumers, and consumers with less-educated were more likely to manage their clothing frequently. Second, it was classified consumers into several groups based on the different purchase behavior style, these were "rational purchasing", "saving-money purchasing", "regretting for their purchasing", and "over-purchasing". Third, "saving-money purchasing" group showed a high expenditure rate in the purchase of used-clothing but a low rate in "over-purchasing" group. The frequency of management of clothing was the highest in the group of "over-purchasing" and the next in the group of "saving-money purchasing". The group of "over-purchasing" were more likely to show irrational decision-making style, manage and disposal their clothing frequently, "saving-money purchasing" purchased used-clothing frequently, and the level of management of clothing were less in the group of "regretting for their purchasing".