• Journal of Korean Society on Water Environment
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• v.35 no.1
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• pp.35-42
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• 2019

Urbanization has led to extreme changes in land use on urban watersheds. Most cities are becoming residential, commercial and industrial areas, making infiltration and storage of rainfall less favorable. The demand for LID (Low Impact Development) technology is increasing in order to mitigate this water cycle distortion and return to existing hydrological conditions. The LID technique is effective in reducing runoff by permeating the urban impervious area. However, considering the limit of the installation area and the financial requirement of the installation, there is not much research on the linkage of each LID component technology for optimum efficiency according to the appropriate scale. In this study, the effects of the LID facilities applied to the target site were simulated using the SWMM model, suggesting the optimal linkage method considering interconnectivity, and applying the effects as an existing installation of individual facilities. The water balance at the time of application of the LID technology, short-term and long-term rainfall event were compared. Also, the individual application and the linkage application were compared with each other. If each component technology has sufficient processing size, then linkage application is more effective than individual application.

• Journal of English Language & Literature
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• v.58 no.1
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• pp.21-42
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• 2012

Gloria Naylor's second novel Linden Hills (1985) explores the issues of self-exploration, empowerment, history, and memory by delineating the communal and familial tragedies and the distortion of values prevalent in a prosperous African-American urban community called Linden Hills. Drawing upon the Freud's concept of "primal scene" and "family romance," this paper aims to focus upon the Nedeed family, the founder of Linden Hills, and investigate the compelling traumatogenic force within the family, which is inseparably intertwined with the inversion of values and moral corruption permeating the entire community. The "primal crime" committed by the Nedeed ancestors serves to preserve and perpetuate a tyrannical rule by ruthless patriarchs who reign by underhanded strategies of purposefully neglecting and abusing others, including their own wives. The imprisonment, by Luther Nedeed, of his wife Willa in the family morgue epitomizes the long legacy running in the family-the oppression and burial of the pre-Oedipal, maternal history. Willa's accidental encounter, at the nadir of the family estate and her personal despair, with the faded records of the forgotten and abused Nedeed women exposes the violence-ridden ground of the family's primal scene and the absurdity of family romance the Nedeeds pursued. As the several lines of poem composed by Willie, Willa's male double, show, the hidden, forgotten history of the Nedeed women, in a sense, is the real, which cannot be assimilated to the social symbolic governed by the inhumane patriarchy of the Nedeed family and the success-oriented Linden Hills society. By portraying a catastrophic downfall of the Nedeed family and the futile outcome of its family romance, the ending of Linden Hills conveys implicitly that the contingent symbolic order and its oppressive control, however solid and invincible they may seem, can be toppled down by the real, its nameless forgotten Other.

• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1135-1145
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• 2024

When cells are exposed to freezing temperatures, high concentrations of cryoprotective agents (CPA) prevent ice crystal formation, thus enhancing cell survival. However, high concentrations of CPAs can also cause cell toxicity. Exopolysaccharides (EPSs) from polar marine environments exhibit lower toxicity and display effects similar to traditional CPA. In this study, we sought to address these issues by i) selecting strains that produce EPS with novel cryoprotective activity, and ii) optimizing culture conditions for EPS production. Sixty-six bacteria producing mucous substances were isolated from the Ross Sea (Antarctic Ocean) using solid marine agar plates. Among them, Pseudoalteromonas sp. RosPo-2 was ultimately selected based on the rheological properties of the produced EPS (p-CY02). Cryoprotective activity experiments demonstrated that p-CY02 exhibited significantly cryoprotective activity at a concentration of 0.8% (w/v) on mammalian cells (HaCaT). This activity was further improved when combined with various concentrations of dimethyl sulfoxide (DMSO) compared to using DMSO alone. Moreover, the survival rate of HaCaT cells treated with 5% (v/v) DMSO and 0.8% (w/v) p-CY02 was measured at 87.9 ± 2.8% after freezing treatment. This suggests that p-CY02 may be developed as a more effective, less toxic, and novel non-permeating CPA. To enhance the production of EPS with cryoprotective activity, Response Surface Methodology (RSM) was implemented, resulting in a 1.64-fold increase in production of EPS with cryoprotective activity.

• Journal of Embryo Transfer
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• v.23 no.4
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• pp.269-274
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• 2008

The purpose of this study was to determine the effects of Taxol pre-treatment to in vitro matured bovine oocytes, and sucrose and trehalose added to vitrification solution on spindle morphology and embryonic development following cryopreservation. Bovine oocytes were collected from ovaries and matured in tissue culture medium 199 (TCM 199) supplemented with 10% Fetal Bovine Serum (FBS), 0.05ng/ml epidermal growth factor, 0.01 IU/ml luteinizing hormone and $1{\mu}g/ml$ estradiol for 22h in $39^{\circ}C$, 5% $CO_2$, TCM 199-HEPES containing 20% FBS was used as basic medium (BM) to prepare vitrification solution. Oocytes were pre-treated with $1\;{\mu}M$ Taxol in maturation medium for 15 min prior to vitrification. Oocytes were exposed to 1.6 M ethylene glycol (EG) and 1.3M dimethyl sulfoxide (DMSO) in BM and then were exposed to 3.2 M EG, 2.6 M DMSO and 0.5 M sucrose in BM or 3.2 M EG, 2.6 M DMSO and 0.5 M trehalose in BM. Oocytes with cumulus cells and oocytes without cumulus cells were considered as control 1 and control 2, respectively and held in TCM 199-HEPES at $39^{\circ}C$. Oocytes were frozen using modified solid surface vitrification and were stored in cryotubes in liquid nitrogen for more than 1 week. Frozen oocytes were thawed in TCM 199-HEPES containing 0.5 M, 0.25 M and 0.1 M sucrose in BM for 2 min, respectively or 0.5 M, 0.25 M and 0.1 M trehalose in BM for 2 min, respectively. Immunoflurorescence staining of oocytes was performed to assess spindle morphology and chromosome configuration of oocytes. The rates of cleavage and blastocyst were examined following in vitro fertilization. Normal spindle morphology rate of oocytes pre-treated with Taxol prior to vitrification was not higher than that of other vitrified groups. Taxol pre-treatment did not increase cleavage and blastocyst formation rates, although control groups showed significantly higher rates (p<0.05). Percentages of normal spindle and embryonic development were not significantly different among vitrified groups regardless of type of sugar. In conclusion, Taxol pre-treatment of oocytes before cryopreservation did not reduce the damage induced by vitrification and subsequently did not improve embryonic development following vitrification. Trehalose may be used as an alternative non-permeating cryoprotectant in vitrification solution.

• The Journal of Engineering Geology
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• v.14 no.3 s.40
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• pp.301-311
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• 2004

This study is suggested a new dielectric tracer test method to understand geological structure of porous media and groundwater flow to use the dielectric constant which is one of electrical special quality of various geological materials. To measure their parameters, tracer material is made an ethanol mixing liquid(EML) having a same specific gravity of water. Also, soil materials are prepared a dielectric tracer test using the FDR system that could measure dielectric constant for saturated standard sand and river sand layers which have different initial porosity. To compare with their results, we discussed with the concentration variation of saline water having a saline concentration $3\%$ which is general tracer material by using the electro multi-meter system in the laboratory or field test. In two tracer experiment results, EML tracer test could confirm definitely EML concentration variation from each saturated soil layer as standard and river sands. However, tracer test of saline water $3\%$ concentration could not confirm permeating movement of water by degree of salinity change because these are settled at lower part column in a whole column area continuously. These causes are that specific gravity of saline water is heavier than water. That is, it could know that deposition of saline water is composed of lower part of soil column continuously independently of the direction of water into saturated soil material.

• Geotechnical Engineering
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• v.9 no.3
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• pp.49-60
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• 1993

The compatibility of chemicals in the leachates with the three natural and artificially -made liner materials is analyzed by performing the laboratory hydraulic conductivity test. The selected liner materials are natural marine clay, fly ash and weathered granitic soil stomped from Kimpo Wastefills, Seochon power plant and Mansu Dong, Inchon, respectivaly. Bentonites of 20 and 10 percent by weight are used as additive materials for fly ash and weathered granitic soil and the chemical solutions used in the test are acetic acid, methanol, heptane, and aniline which are frequently found in the leachate of waste fills. The concentrations of the chemical solutions are 100% and 75%. The results of the tests show that hydraulic conductivities of the oxter materials are increased by one or two orders of magnitude with permeating pure chemical solutions. The rate of hydraulic conductivity increase is lowest for Seochon fly ash admixed liner and highest for natural marine clay liner. The influence of hydraulic chemical solutions on the liner materials is least for acetic acid and largest for aniline. The increases of conductivity are not shown with the permeation of the solution of concentration 75%. At least by this test results, it can be recognized that the tested liner material can be quite stable with the solutions of significantly high concentration except pure solutions.

• Journal of Technologic Dentistry
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• v.30 no.1
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• pp.83-96
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• 2008

This study aims to analyze the major factors in their working conditions affecting the enlargement of leisure activities of dental technicians. We also present a need for dental technicians to assign more time many different kinds of leisure activities for their quality life. To this end, we examined the status and the characteristics of dental technicians' leisure activities among the randomly selected subjects who are working in the area of Seoul, Gyonggido, and Gangwon-do through the analysis of the 311 sheets of self-administered questionnaires. The conclusions from this analysis are as follows; 1. On weekdays, non participants in leisure activities were found to be 64.0%, and in the case of weekends, the participants were reached to 70.7%. Those who enjoy any leisure activities in either of weekdays and weekends were 34.1%, 27.3% of the dental technicians did not have any leisure activities. Therefore, statistical significance was shown in the participations of leisure activities between weekdays and weekends. 2. Of the types of leisure activities in both weekdays and weekends, sports activities were ranked at the top 33.4%, 29.6% respectively, which is followed by going to the cinema/theatre/exhibitions, etc 21.9%, 26.0%, games/entertainment 14.5%, 14.8%, hobbies/cultural activities 14.1%, 12.5%, sightseeing/picnic 6.4%, 7.4%. 3. Of the differences in the characteristics of leisure activities, the types of leisure activities between weekdays and weekends showed difference in gender, company and information regarding leisure activities in age, company and the place of leisure activities, and leisure information in the marital status, career and monthly income in company, company and leisure information in the job position, which is statistically significant (p<.001). However, no statistical significance was found among the other general items of the characteristics of leisure activities. Considering only works on weekdays policy is currently permeating into almost every business sector, dental business owners or managers are advised to consider more effective time management or human resources management, such as keeping reasonable manufacturing time through cooperations with the dentists, regularity of working hours, incentive system, introduction of credible over time payment. Which will provide their staff with more times and opportunities to enjoy their leisure activities. Additionally, the concrete and feasible ways of motivating and activating the leisure activities of dental technicians are in need of further researches and studies.

• Journal of The Korean Association of Information Education
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• v.10 no.1
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• pp.107-115
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• 2006

As the use of computers and the Internet become more commonplace, many children are using the Internet. The Internet is rapidly permeating into the daily lives of elementary school students. There are some positive effects of using the Internet: it helps children's studies and communication skills and relives stress. However, some negative effects are arising, such as aggressive behavior caused by Internet games, sleeping disorders, and Internet addiction. The goal of this disquisition was to find out how an upper class of elementary school children are using the Internet and also the degree of their Internet addictions. The effects that Internet addiction had on various aspects, such as on the individual, family, and school were observed. In the individual aspect, self-respect, self-control, awareness of stress, depression, and personal taste were observed. In the aspect of family, communication with parents, the nursing behavior of parents, family functions, friendliness within the family, and the family's emotional support were observed. In the aspect of school, relationships with teachers, relationships with friends, study activities, compliance to rules and participation in events were observed. By analyzing each cause of Internet addiction, this disquisition hopes to help prevent Internet addiction and to support educational guiding about Internet addiction of elementary school children.

• Journal of the Korea Convergence Society
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• v.9 no.5
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• pp.33-41
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• 2018

The purpose of this study is to develop more accurate and robust emotion prediction neural network (EPNN) model by combining heart rate variability (HRV) and neural network. For the sake of improving the prediction performance more reliably, the proposed EPNN model is based on various types of activation functions like hyperbolic tangent, linear, and Gaussian functions, all of which are embedded in hidden nodes to improve its performance. In order to verify the validity of the proposed EPNN model, a number of HRV metrics were calculated from 20 valid and qualified participants whose emotions were induced by using money game. To add more rigor to the experiment, the participants' valence and arousal were checked and used as output node of the EPNN. The experiment results reveal that the F-Measure for Valence and Arousal is 80% and 95%, respectively, proving that the EPNN yields very robust and well-balanced performance. The EPNN performance was compared with competing models like neural network, logistic regression, support vector machine, and random forest. The EPNN was more accurate and reliable than those of the competing models. The results of this study can be effectively applied to many types of wearable computing devices when ubiquitous digital health environment becomes feasible and permeating into our everyday lives.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.25 no.3
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• pp.95-99
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• 2019

In the modified atmosphere packaging of powdered infant formula, the oxygen inside the package may cause its quality deterioration and needs to be minimized for quality preservation. A way of oxygen scavenger inclusion in the single-serve package without contacting the product was devised for removing oxygen residing initially and permeating through the seal layer during the storage. A polyethylene/pulp multi-layer porous filter bag of 5 × 7 cm containing 13 g of powdered infant formula was packaged in an 8 × 9 cm size aluminium laminated film package with a Fe-based oxygen scavenger of 1.8 g. After nitrogen flushed packaging, the active packages were stored at 30℃ for 254 days with periodical quality measurement. The active package could remove the initial residual oxygen of 1.4% completely and maintain absence of oxygen for the whole storage, which contributed to reduced oxidation observed in lower product peroxide value compared to that of the product in the control package. There was no influence of packaging treatment on content of 5-hydroxymethylfurfural, reaction product of initial nonenzymatic browning. The devised oxygen-scavenging single-serve package showed a potential to improve the preservation of infant formula powder and extend the shelf life.