• Journal of Convergence for Information Technology
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• v.9 no.10
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• pp.203-212
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• 2019

The purpose of this study was to identify the effects of stress factors of student pilots on mental health, and to reduce the safe and efficient misconduct education and psychological disharmony by identifying the psychological buffering role of stress coping style and social support. In order to achieve the research purpose, a research model and hypothesis were presented based on previous studies, and regression analysis and mediation effect verification were conducted through a questionnaire survey of 202 student pilots. As a result of the analysis, factors such as flight stress, values stress, professor stress, and friend relationship stress have been shown to affect emotional conditions or psychological well-being. Also we found that the parameters of disengagement coping, family/friend support and organization Support had a mediating effect on the factors between student pilot stress and psychological health. Therefore, student pilots need to manage problems and negative emotions that may cause from flight training, value distractions, professor and friendships' relationship and it is suggested that organization support for training and safety related to emotional support and delinquency of family and friends.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.3169-3183
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• 2018

Based on the affective event theory, the purpose of the study is to examine the effect of the individual difference regulatory focus on the process in which the work events affect job engagement under organizational circumstances. To this end, 232 financial workers were surveyed on positive events, positive affects, regulatory focus and job engagement. The results of the analysis are as follows. First, the positive events generated positive affects and showed positive influence on job engagement. Second, the effect of positive affects on job engagement has been shown to be discriminatory depending on the level of regulatory focus. The higher the level of promotion focus, the stronger the effect on job engagement of positive affects, and the higher the level of prevention focus, the weaker the effect on job engagement of positive affects. Third, the moderated mediated effect was found to be significant only in the prevention focus. The magnitude of indirect effects on job engagement by positive events was found to be weakened when the prevention focus was high. Finally, the implications and future research issues were discussed.

• Journal of Family Resource Management and Policy Review
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• v.20 no.3
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• pp.131-149
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• 2016

The aims of this study are to investigate the impact of the experience of exposure to domestic violence(witnessed interparental conjugal violence and child abuse) on mental health among college students, and to explore whether social support acts as a moderator between domestic violence and mental health. Through this process, I intended to provide a reference base to suggest substantial interventions for family welfare by helping students to overcome negative domestic violence exposure experiences and adapt as healthy members of society. To achieve this goal, the study established a conceptual framework by considering the mental health of adolescents with domestic-violence exposure experience as a dependent variable, domestic violence exposure experience (witnessed interparental conjugal violence and child abuse) as an independent variable, and social support as a moderator of the relationship between these two variables. The subjects composed 747 college students in 8 colleges in Seoul. The main summary of this study is as follows: First, according to the analysis of domestic-violence exposure experience, all the subjects of this study had substantial experience of violence at home and witnessed interparental conjugal violence. These students scored 3.83 points in social support, higher than the median of 3, implying that these students had a higher awareness of social support. Moreover, their mental health score was 3.50 points, which is higher than the median of 3, indicating a somewhat positive tendency toward mental health. Second, to explore the moderating effects of social support between child violence experience and mental health, gender, age, financial status, academic-performance, child abuse and social support were input in the first step, and then buffering effects were examined by entering an interaction term to the first step in the second step. There was a significant interaction between social support and mental health. Therefore, social support was identified as having moderating effects on the relationship between child violence and mental health. Third, the analysis of moderating effects of social support between witnessed interparental conjugal violence and mental health revealed that social support had a positive influence on mental health in the first step. By contrast, the interaction term of witnessed interparental conjugal violence and social support showed no significance, indicating no moderating effect of social support in the second step. To sum up, social support served as a moderator for mental health among college students with child abuse experience, but had no moderating effect on witnessed interparental conjugal violence experience.

• Informatization Policy
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• v.26 no.2
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• pp.46-61
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• 2019

This study constructs an integrated model for university students' smart phone cyber bullying and tests interaction effects between causal and control factors. Causal factors include low self-control, differential association with cyber bullying peers, and victimization experiences; and control factors include internet ethics, perceived certainty of formal punishment, and bond to parents. This study focuses on examining how internet ethics buffers the effect of causal factors in cyber bullying. Results show that both differential association with cyber bullying peers and victimization experiences have significant effects on cyber bullying. And among the control factors, internet ethics only has a negative direct effect on cyber bullying. In addition, it is found that there are significant interaction effects between two causal factors - differential association with cyber bullying peers and victimization experiences - and internet ethics. It is also shown that there is a significant interaction effect between victimization experience and bond to parents, but a perceived formal punishment has no significant control effect. It is revealed that internet ethics is a main control factor in buffering the effects of causal factors in cyber bullying.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.6
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• pp.13-22
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• 2006

The purpose of this study is to propose rational methods in order to maintain vegetation condition and soil environment based on the analysis of tree growth in relation to the soil environment, which is one of the most significant environmental factors on vegetation condition in urban parks and open spaces. The result of the study can be described as below;The soil on every study site had strong acidity. In particular, study sites around industrial district and central business district showed extreme soil acidity. Therefore, soil management system is needed in urban parks and green spaces around those areas. Among Cambium Electric Resistance classified by locations of urban parks and open spaces, one in the costal area was the lowest. The Cambium Electric Resistance in the industrial area was the highest. Therefore, soil condition and locational environment in the industrial area are highly related to the Cambium Electric Resistance. Among the factors, which affect Cambium Electric Resistance in different locations, inorganic content was found to be the main factor in all of the study sites. Inorganic content was an important factor to the Cambium Electric Resistance in study sites located in industrial and central business districts. In the study sites located in costal area, Soil acidity was found to be other important factors that affect Cambium Electric Resistance. To improve the soil acidity, soil buffering ability should be improved from activating microorganisms in the soil by using lime and organic material, Since it takes a long time to make a change in the soil structure, well planed maintenance system is required by mid-term or long-term plans.

• Journal of Family Resource Management and Policy Review
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• v.23 no.4
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• pp.23-39
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• 2019

This study aimed to explore the moderating effect of family strengths on the effect of work-family conflict on happiness in dual-income married couples. This study included 316 married employees who live in Seoul and have children attending junior high or lower grade schools. A survey was conducted December 1-30, 2018 by distributing questionnaires to child care centers, kindergartens, schools, companies, religious institutions, and other locations. The results are follows. First, in this study, the degree of family→work conflict was higher than that of work→family conflict in dual-income married couples, indicating that role conflict at work is greater due to family role pressures. Second, among the socio-demographic characteristics of dual-career couples, monthly income, family→work conflict (an independent variable), and family problem-solving skills (a moderating variable; a subcategory of family strengths) had a significant impact. In the analysis of the effect of work-family conflict on happiness, the higher the monthly income, the lower the family→work conflict, and the higher the family problem solving ability, the higher the feeling of happiness among dual-income married couples. When the work role conflicts from family life roles were more highly perceived in dual-income married couples. Moreover, family→work conflict and an interaction term of family problem-solving ability were identified as variables that had significant effects on happiness. Third, family problem-solving ability was identified as a moderator buffering the effect of work-family conflict on happiness.

• Journal of Environmental Science International
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• v.25 no.12
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• pp.1689-1699
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• 2016

The growth conditions of planted trees, invasion of nuisance herbaceous species, competition between species, and effects of erosion control were monitored over five years in a riparian greenspace in Gapyeong County that was established through multilayered and grouped ecological planting. Of 156 trees planted in the upper and middle layers, 5.8% died. This tree death was attributed to poor drainage or aeration in the rooting zone from the clay-added root ball and too deep planting as well as a small-sized root ball and scanty fine roots. Of all the trees, 21.6% grew poorly due to transplant stress in the first year after planting, but they started to grow vigorously in the third year. This good growth was largely associated with soil improvement before planting, selection of appropriate tree species based on growth ground, and control of dryness and invasive climbing plants through surface mulching and multilayered/grouped planting. Mixed planting of fast-growing species as temporary trees was desirable for accelerating planting effect and increasing planting density. Thinning of fast-growing trees was required in the fifth year after planting to avoid considerable competition with target species. To reduce the invasion of herbaceous and climbing plants that oppress normal growth of planted trees, higher density planting of trees (crown opening of about 15%), woodchip mulching to a 10-cm depth, and edge planting 2 m wide were more effective than lower density planting (crown opening of 70%), no surface mulching, and no edge planting, respectively. This reduction effect was especially great during the first three years after planting. Nuisance herbaceous plants rarely invaded higher density planting with woodchip mulching over the five years. Higher density planting or woodchip mulching also showed much greater erosion control through rainfall interception and buffering than lower density planting with no mulching did. Based on these results, desirable planting and management strategies are suggested to improve the functions of riparian greenspaces.

• Molecules and Cells
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• v.19 no.3
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• pp.382-390
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• 2005

Calcium-binding proteins are thought to play important roles in calcium buffering. The present study investigated the effects of ischemia and reperfusion on calbindin D28K, calretinin, and parvalbumin immunoreactivity in the ganglion cell layer of the rabbit. Rabbits were administered ischemic damage by increasing the intraocular pressure. After 60 and 90 min of ischemia, reperfusion (7 d) was allowed to occur. The b-wave of the electroretinogram (ERG) was reduced by more than 50% and almost 80% in retina given ischemia for 60 and 90 min, respectively. The oscillatory potential (OPs) wave was reduced approximately 50% at 60 min ischemia and 70% at 90 min ischemia. In both normal and ischemic-treated retina, calcium-binding protein immunoreactivity was seen in many cells in the ganglion cell layer. In eyes subjected to 60 min ischemia, there was a decrease of the density of calbindin D28K- (8.29%), calretinin- (14.44%), and parvalbumin- (26.83%) immunoreactive (IR) cells compared to the control retina. In eyes subjected to 90 min ischemia, there was a higher decrease of the density of calbindin D28K- (18.48%), calretinin- (33.59%), and parvalbumin- (54.26%) IR cells than at 60 min. Some calcium-binding protein-IR neurons, especially calretinin-IR neurons, showed aggregations that were abnormally packed together in retina subjected to ischemia for 90 min. The results show that calbindin D28K-, calretinin-, and parvalbumin-IR cells in the ganglion cell layer are susceptible to ischemic damage and reperfusion. The degree of reduction varied among different calcium-binding proteins and ischemic damage times. These results suggest that calbindin D28K-containing neurons are less susceptible to ischemic damage than calretinin- and parvalbumin-containing neurons in the ganglion cell layer of rabbit retina.

• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.173-177
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• 2000

The synthetic carbon was coated with tin oxide and copper by fluidized-bed chemical vapor deposition method. $(CH_3)_4Sn\;and\;Cu(hfac)_{2s}$ were employed as the metallic organic precursor, respectively. The modified synthetic carbons were used for lithium secondary battery anode to investigate their coating effects on electrochemical characteristics as alternative anode materials for lithium secondary batteries. The electrode which prepared by the synthetic carbons(MCMB) coated with tin oxide gave the higher capacity than that of raw material. Their capacity decreased with the progress of cycling possibly due to severe volume changes. But the cyclability was improved by coating with copper on the surface of the tin oxide coated carbon, which plays an important role as an inactive matrix buffering volume changes.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1653-1658
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• 2012

We have reported previously that a recombinant Escherichia coli co-expresses aminolevulinic acid (ALA) synthase, an NADP-dependent malic enzyme, and a dicarboxylate transporter-produced heme, an iron-chelated porphyrin, in a succinate-containing complex medium. To develop an industrially plausible process, a chemically defined medium was formulated based on M9 minimal medium. Heme synthesis was enhanced by adding sodium bicarbonate, which strengthened the C4 metabolism required for the precursor metabolite, although a pH change discouraged cell growth. Increasing the medium pH buffering capacity (100mM phosphate buffer) and adding sodium bicarbonate enabled the recombinant E. coli to produce heme at rates 60% greater than those in M9 minimal medium. Adding growth factors (1 mg/l thiamin, 0.01 mg/l biotin, 5 mg/l nicotinic acid, 1 mg/l pantothenic acid, and 1.4 mg/l cobalamin) also induced positive heme production effects at levels twice of heme production in M9-based medium. Porphyrin derivatives and heme were found in the chemically defined medium, and their presence was confirmed by liquid chromatography/mass spectroscopy (LC/MS). The formulated medium allowed for the production of $0.6{\mu}M$ heme, $29{\mu}M$ ALA, $0.07{\mu}M$ coproporphyrin I, $0.21{\mu}M$ coproporphyrin III, and $0.23{\mu}M$ uroporphyrin in a 3 L pH-controlled culture.