• Journal of the Korean Chemical Society
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• v.61 no.4
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• pp.143-150
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• 2017

Countercurrent oxidation process (COP) was developed and evaluated for treatment of highly concentrated PCB containing insulating oil. The PCB content in insulating oil taken from Haksanmetal company was found to be 1,512 ppm. The COP utilizes a self-sustained flame which propagates itself in a direction counter to the oxygen flow. The flame removes PCBs adsorbed in activated carbon and, at the same time, regenerates activated carbon. The flame temperature was determined from both mass loss of activated carbon and the relative ratio of CO and $CO_2$ exhausted during COP, and showed that its temperature lied in the range of $650-850^{\circ}C$. Removal efficiency of PCBs was achieved above 99.99% for 5% of insulating oil loaded activated carbon with 1 COP in weight ratio. Also, the same removal efficiency was acquired for 60% of insulating oil loaded activated carbon with three consecutive COP. In addition, specific surface area of activated carbon during COP was recovered to almost similar value of virgin activated carbon. It proved that the COP was much effective in removing high concentration of PCBs in insulating oil easily and affordably.

• Journal of The Korean Association For Science Education
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• v.33 no.1
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• pp.79-93
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• 2013

This study examined value-judgement and decision-making process of middle school students on three biotechnology related socioscientific issues (SSI) (i.e. designer baby, amniotic fluid test, and embryonic stem cell research). In particular, it focused on the level of consistency in their value application to the decisions. Twenty 8th grade students participated in the SSI program. The participants were asked to mark their positions on each issue before and after the debates. All classroom and sub-group debates were audio-recorded. The researcher conducted individual interviews with 10 students after the program. The results show three patterns emerging. First, five students applied their personal values in a consistent manner when making decisions on the three consecutive issues. Second, three students demonstrated incremental resoluteness in their value application as the sessions proceeded and had tendency to be oriented towards a specific value, more so towards the end of the program than the beginning. And third, four students gradually showed ambivalence in their decisions as they participate in the program. The results suggest that science teachers addressing SSI need to encourage students to be aware of their own values and to engage in internalized decision-making in light of those values. They also need to be aware of the possible challenges that students might feel in their decision-making process caused by the complexity of SSI.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.92-97
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• 2005

Inhibition of inflammatory response, acceleration of basal cell growth, and balanced synthesis of extracellular matrix (ECM) are important in healing of cutaneous open wounds. In order to evaluate the healing effects of water extracts of Radix Astragali (the root of Astragalus membranaceus (Fisch.)) on open wound at early stage, the experimental open wounds were generated on the dorsal sides of SD rats under anesthesia. The boiled-water extracts of Radix Astragali $(100{\mu}l)$, soaked into an occlusive film dressing were applied once a day for eleven consecutive days. The healing process was assessed by measuring macroscopic appearance and wound areas of the open wounds. The molecular aspects of healing process by Radix Astragali extracts were also investigated by Hematoxylin-Eosin (H-E) double staining and immunohistological staining of collagen type I in the healed skin area, implying cell density and linear alignment of the granulation tissue, and ECM synthesis and its remodeling, respectively. The Astragali radix extracts were found to significantly accelerate the cutaneous wound healing by suppressing the inflammation and stimulating the basal cell growth in wounded area, as compared to epidermal growth factor (EGF).

• Journal of Korean Neurosurgical Society
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• v.61 no.4
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• pp.503-508
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• 2018

Objective : Anterior odontoid screw fixation is a safe and effective method for the treatment of odontoid fractures. The surgical technique is recommended for perforation of the apical cortex of the dens by the lag screw. However, overpenetration of the apical cortex may lead to potentially serious complications such as damages of adjacent vascular and neural structures. The purpose of this study was to assess the role of three-dimensional computed tomography (CT) scan to evaluate the safe margin beyond dens tip to ventral dura for anterior odontoid screw fixation. Methods : We retrospectively analyzed the three-dimensional CT scans of the cervical spines in 55 consecutive patients at our trauma center. The patients included 38 males and 17 females aged between 22 and 73 years (mean age${\pm}$standard deviation, $45.8{\pm}14.2years$). Using sagittal images of 3-dimensional CT scan, the safe margins beyond dens tip to ventral dura as well as the appropriate screw length were measured. Results : The mean width of the apical dens tip was $9.6{\pm}1.1mm$. The mean lengths from the screw entry point to the apical dens tip and posterior end of dens tip were $39.2{\pm}2.6mm$ and $36.6{\pm}2.4mm$. The safe margin beyond apical dens tip to ventral dura was $7.7{\pm}1.7mm$. However, the safe margin beyond the posterior end of dens tip to ventral dura was decreased to $2.1{\pm}3.2mm$, which was statistically significant (p<0.01). There were no significant differences of safe margins beyond dens tip to ventral dura with patient gender and age. Conclusion : Extension by several millimeters beyond the dens tip is safe, if the trajectory of anterior odontoid screw is targeted at the apical dens tip. However, if the trajectory of the screw is targeted to the posterior end of dens tip, extension beyond dens tip may lead to damage immediately adjacent to the vental dura mater.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.5 no.1
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• pp.93-112
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• 2010

Korea has risen to one of the most newly industrialized countries boasting its consecutive successful economic growth. The economic growth brought the Korean people more money and free time. Koreans all want to spend more time on leisure activities and travels. In this "mass Tour Age", because of its diverse functions and excellent facilities, resort condominium has been got much more attention. Instead of analyzing whole condominium operations, we put more emphasis on the room reservation system for the efficiency of operation. The purpose of this study is to identify the problems of current condominium operations and to suggest innovative new solutions. To accomplish the purpose, we analyzed the current room reservation system of condominiums in Korea. After reviewing the current reservation system, we provide a couple of suggestions. In order to improve reservation process, future demands should be forecasted as accurately as possible, or be based on everything from sophisticated technological system. I wish this study can help innovate the current reservation problems of the resort condominium industry for continuous improvements of the industry.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.219-225
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• 2000

The spinel structured $LiMn_2O_4$was obtained by two consecutive heat treatment on xerogel; the first heat treatment was at $150^{\circ}C$ and the second at $350^{\circ}C$ was obtained by sol-gel process using an aqueous solution of lithium hydroxide and manganese acetate. The synthesized $LiMn_2O_4$ by the sol-gel process showed a discharge capacity of 88~56 mAh/g after 15 cycles in Li/lM $LiClO_4$(in PC)/$LiMn_2O_4$at a current density of 0.25 mA/$\textrm{cm}^2$ and the voltage ranged 3.5 V to 4.3 V. For the second heat treatment above $350^{\circ}C$, $Mn_2O_3$was formed as a by-product during the synthesis of $LiMn_2O_4$. The heat treatment at $500^{\circ}C$, for example, showed a lower discharge capacity 81~47 mAh/g, after the 15 charge/discharge cycles. The lower capacity was due to the increment of $Mn^{3+}$ ion and this phenomenon was in agreement with the Jahn-Teller distortion.

• Journal of The Korean Association For Science Education
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• v.41 no.4
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• pp.311-324
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• 2021

In this study, we analyzed the process of pre-service science teachers' designing and implementation of lessons in teaching practice from the perspective of CHAT. Five pre-service teachers attending the Department of Chemistry Education at the College of Education in Seoul participated in this study. We observed their teaching practice, collected documentary data, and conducted in-depth interviews. The data were analyzed using the constant comparative method based on grounded theory. The analyses of the results reveal that, due to the lack of authority to make decisions for lesson design, pre-service teachers faced difficulties and had direct conflict with teachers. In addition, it was difficult for them to obtain sufficient contextual information for lesson design even through subject orientation and classroom observation, which made it difficult for them to design lessons. When consecutive lessons were taken by several pre-service teachers, there were many problems such as poor continuity of lessons. Given limited authority to assess students, they conducted additional assessments. They showed a lack of professionalism when conducting assessments. The cause of this could be found in the curriculum of the College of Education. Some ways to provide better teaching practice based on the results are discussed.

• Industry Promotion Research
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• v.8 no.3
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• pp.51-60
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• 2023

The purpose of this study was to verify the double mediating effects of job stress and psychological commitment in the relationship between organizational incivility and job satisfaction of child-care teachers in South Korea. 234 Korean child-care teachers were purposively selected from S city of C Province. SPSS Win.25.0 and PROCESS Macro 4.2 were used for analyzing the data, and reliability analysis, frequency analysis, correlation analysis, and multiple mediation model analysis were conducted. Results are as follows. First, correlation analysis showed significant correlations between organizational incivility, job stress, psychological commitment, and job satisfaction. Second, path analysis showed that organizational incivility had a positive effect on job stress and a negative effect on psychological commitment and job satisfaction. Job stress had a negative and significant effect on psychological commitment and job satisfaction, and psychological commitment had a positive and significant effect on job satisfaction. Third, job stress and psychological commitment had consecutive double mediation in the link between organizational incivility and job satisfaction. This study suggests a way to utilize job stress and psychological commitment when childcare teachers' organizational incivility has a negative effect on job satisfaction.

• Korean Journal of Social Welfare Studies
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• v.41 no.3
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• pp.443-475
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• 2010

Despite the rapidly increased concern on the circularity of the program development activities in the social service agencies, there are only a few studies about the phenomena. This study is to describe the characteristics of program development in the process of adopting, developing, and disseminating the social programs and to figure out the factors influencing differences in the 3 activities in social service agencies. The researchers constructed an explanative model including each 12-13 independent variables with 3 consecutive dependent variables on the basis of reviewing the related literatures. A multiple regression analysis was applied to predict the features of the program development using 195 questionaries responded from social workers in community service centers. As the result of the descriptive analysis, the two noticeable features are found; (1) the agencies have very actively adopted outside programs, developed appropriate programs for the agency, and disseminated the programs into other agencies in the community. (2) there are some positive aspects of the factors in related to the process of the program development. The results of the regression analysis show that the three dependent variables of the adoption, development, and dissemination are very closely interconnected with each others, showing the evidence of the circularity in the agencies. In addition, the 5 independent variables at the value of p .01 are statistically related with the circularity of the three dependent activities. The implication of major findings were discussed in academic and practical perspectives in Korea, including future research works in the area.

• Korean Journal of Cognitive Science
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• v.27 no.3
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• pp.441-467
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• 2016

This fMRI study is aim to investigate effects of competitive environment in cognitive empathic process in human brain. Empathy is known as a crucial factor for human's adaptive behavior in aspects of social cognition and it is almost automatic process, on the other hand competitive situation is psychologically devastated environment to win someone for getting rewards. We hypnotized that reading and understanding of other person's mind are a specific characteristic related to survival evolutionarily, however competition would have an effect on the empathic cognitive process because of mechanisms of competition. To manipulate the competitive atmosphere, one researcher took a role of competitor against participants and they were instructed to get monetary rewards when their performance was better than a competitor. 21 participants(9 males and 12 females) performed to judge the emotional valence of the empathic task consisted of illustrated images with various situation could be experienced in real world as on $1^{st}$ person perspective in both competitive and non-competitive condition, and did same performance with objects stimulus in control condition. In order to examine the competition effects on empathic process,, hemodynamic response were obtained during fMRI session and the imaging data were analyzed to identify brain regions where responses to each condition across the two consecutive runs. Participants' reaction time in competitive condition was faster statistically significant than non-competitive one. Activation for competitive condition increased in the following areas: ACC, mPFC, SMG, thalamus extended caudate and Nacc, parahippocampal gyrus, and for non-competitive condition increased paracingulate gyrus, temporal pole, vmPFC, superior occipital gyrus. As a result of regression analysis using empathic scores as covariance, the rSMG, IFG, fusiform gyrus, thalamus, putamen were correlated with higher empathic levels, and TPJ were correlated with lower empathic scores. We suggest that these observations could mean competitive environment have an effect on neural base of cognitive empathic process.