• Journal of Environmental Science International
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• v.29 no.11
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• pp.1065-1078
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• 2020

The statistical characteristics of aerosol-cloud interactions over East Asia were investigated using Moderate Resolution Imaging Spectroradiometer satellite data. The long-term relationship between various aerosol and cloud parameters was estimated using correlation analysis, principle component analysis, and Aerosol Indirect Effect (AIE) estimation. In correlation analysis, Aerosol Optical Depth (AOD) was positively Correlated with Cloud Condensation Nuclei (CCN) and Cloud Fraction (CF), but negatively correlated with Cloud Top Temperature (CTT) and Cloud Top Pressure (CTP). Fine Mode Fraction (FMF) and CCN were positively correlated over the ocean because of sea spray. In principle component analysis, AOD and FMF were influenced by water vapor. In particular, AOD was positively influenced by CF, and negatively by CTT and CTP over the ocean. In AIE estimation, the AIE value in each cloud layer and type was mostly negative (Twomey effect) but sometimes positive (anti-Twomey effect). This is related to regional, environmental, seasonal, and meteorological effects. Rigorous and extensive studies on aerosol-cloud interactions over East Asia should be conducted via micro- and macro-scale investigations, to determine chemical characteristics using various meteorological instruments.

• The Korea Journal of Herbology
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• v.21 no.1
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• pp.1-7
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• 2006

Objectives: To find out the effects GGT1, an antiobestic drug widely used clinics, has on the amount of feed intake, the amount of change in the body weight and the food efficiency ratio using the data from the hGHTg obese male rats. Also, to evaluate in terms of antiobestic effects, the difference between GGT1 and reductil (sibutramine), which has been approved by the FDA of the United States. Methods: We measured the change in body weight and the amount of feed intake for 8 weeks by categorizing the hGHTg obese male rats into three groups: the control group, the GGT1 group, and the reductil (RD) group. We also evaluated the antiobestic effect by calculating the food efficiency ratio, which is the increase of bodyweight divided by the amount of feed intake. Results: In case of body weight, moderate slope of the curve in the graph of GGT1 group could mean that the weight is decreasing as time flows. In case of food efficiency ratio, the p-value was 0.745 in a test for determining if an interaction exists between the group and the point of measurement, meaning that it does not exist; also, the p-value in a test for the effect of level of repetition in food efficiency ratio according to the point of measurement equaled 0.002. Conclusion: The drug-treated groups had a greater inhibitory effect in feed intake than the control group. The results showed the food efficiency ratio had a tendency to decrease. The GGT1 group in particular was under a greater effect than the RD group.

• Advances in environmental research
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• v.3 no.4
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• pp.355-365
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• 2014

The present study has been performed on one year old tree saplings of Azadirachta indica (L.), Cassia siamea (L.), Dalbergia sissoo (Roxb.), Eucalyptus rostrata (L.), Mangifera indica (L.) and Schyzygium cumini (L.) in order to assess the effect of exposure of $SO_2-NO_2$, alone and combination of two gases. Tree saplings have been exposed to an average of $495{\mu}g\;m^{-3}$ $SO_2$ and $105{\mu}g\;m^{-3}$ $NO_2$ for 40 d at the rate of $4hd^{-1}$ during 10:00 am to 01:00 pm in OTC. Total chlorophyll, specific leaf area (SLA), nitrate reductase (NR) activity, foliar protein, free proline content and free amino acids (AAs) of foliage have been the plant parameters, taken into consideration to evaluate the effect of gaseous exposure. Exposure of two gases has caused reduction in total chlorophyll content (P < 0.05, 0.01). Physiological and biochemical process has been seemed to be altered noticeable due to the combined effect of $SO_2+NO_2$ followed by $SO_2$ alone (P < 0.05, 0.01). $NO_2$ mediated stress has produced, stimulatory and inhibitory responses in tree saplings. Results reveal that tree saplings have been attempted to absorb the $NO_2$ through N assimilation pathway. E. rostrata, C. siamea have been emerged as moderate tolerant to $SO_2$ mediated stress followed by A. indica. Response pattern of S. cumini, M. indica and D. sissoo set them as good indicators of $SO_2-NO_2$ exposure. Effects of two gases on tree saplings have been found to be synergistic.

• The Mathematical Education
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• v.59 no.1
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• pp.31-45
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• 2020

Despite the trend of the times and the government's efforts to implement policies, a number of students, having difficulties in learning math, are still growing. Reflecting this, many studies related to underachiever of learning mathematics were conducted in the field of mathematics education. Most of these studies, however, were intended to find the cause of underachievers of learning mathematics or experimental studies that applied the specific teaching procedures to the underachievers of learning mathematics and found their effectiveness in terms of academic achievement, compared it beforehand. Thus, in this study, 49 studies, from including theses and published journal papers from 2001, were meta-analyzed to find out how effective the teaching treatment for underachievers of learning mathematics has improved academic performance. As a result of this analysis, we found that teaching treatment generally have moderate effect sizes for children with having difficulties in learning mathematics. It was also possible to analyze the effect of various interventions and to obtain some suggestions on which circumstances the greatest effect could be achieved. Teaching treatments for underachiever of learning mathematics could have greater effectiveness in elementary school level, institution certified testing tool was used, targeted for each individual, taught by peer student, lasted for at least 8 weeks, and using teaching aids and ICT tools.

• Journal of Korean Society for Quality Management
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• v.50 no.4
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• pp.777-792
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• 2022

Purpose: This paper investigates the effects of leader feedback on employee creative problem-solving behavior. It also explores the relevant conditions that maximize the above relationship from the psychological trait and task nature perspectives. Specifically we examine how employee feedback acceptance and task complexity moderate the relationship between leader's feedback behavior on follower creative problem-solving behavior. Finally the three-way interaction among leader's feedback behavior, employee feedback acceptance and task complexity is analyzed for the best conditions to maximize the positive effect of leader's feedback on creative problem solving behavior. Methods: This paper used a cross-sectional design with questionnaires administered to 411 employees working in Korean manufacturing and service firms. It applied a hierarchical regression analysis to test the hypothesized relationships including three-way interaction effect among leader's feedback behavior, follower feedback acceptance and task complexity on follower creative problem-solving behavior. Results: The empirical results of the paper indicated that the leader feedback behavior had enhanced employee creative problem-solving behavior. It was also found that follower feedback acceptance and task complexity positively moderated the relationship between leader's feedback and follower problem solving behavior. In addition, the test of three-way interaction effects also revealed that the higher the levels of both employee feedback acceptance and task complexity, the greater the positive effect of leader feedback behavior on employee creative problem solving behavior. Conclusion: This paper contributes to the leadership and creativity literatures by identifying the role of leader's behavior enhancing employee creative problem-solving behavior and the specific conditions strengthening the positive effect of leader feedback behavior on employee creative problem-solving behavior.

• Journal of Industrial Convergence
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• v.20 no.2
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• pp.21-27
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• 2022

Purpose: The purpose of this study is to investigate the structural relationship between self-directed learning, online class environment, and learning satisfaction of general high school students. 219 12th grade students in Sejong B High School responded to the survey questionnaire. For data analysis, correlation analysis and structural equation models were implemented. Results are as follows. First, there was a moderate or higher correlation between self-directed learning, online class environment, and learning satisfaction. Second, the model fit of the structural model among variables was good. Self-directed learning had an effect on the online class environment, and the online class environment had a positive effect on learning satisfaction. However, self-directed learning had no statistically significant effect on learning satisfaction. The researcher found the implication that learners' online class satisfaction showed a synergistic effect when students' self-directed learning ability and educators' excellent class environment are created. Also, the researcher proposed to analyze online learning satisfaction by comprehensively considering the individual, family, and school factors of various learners.

• Korean Journal of Culture and Social Issue
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• v.24 no.3
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• pp.429-449
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• 2018

The purpose of this study was to examine whether gender collective self-esteem would moderate the relationship between perceived gender discrimination and belief in a just world (BJW) after controling the effect of personal self-esteem. For this, we measured perceived gender discrimination, personal self-esteem, gender collective self-esteem, and BJW in a sample of 300 women and conducted hierarchical regression analysis. The results revealed that, after controlling the effect of personal self-esteem, gender collective self-esteem moderated the association between perceived gender discrimination and BJW. That is, as gender collective self-esteem became greater, the negative effect of perceived gender discrimination on BJW decreased. In addition, we tested if four aspects of gender collective self-esteem (e.g. membership, private, public, identity) moderated the relationship between perceived gender discrimination and BJW. It was found that all of the four aspects except identity had significant moderating effects. Finally, we discussed limitations, suggestions for future research and clinical implications.

• The korean journal of orthodontics
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• v.53 no.6
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• pp.374-392
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• 2023

Objective: Assess and evaluate the different indicators of oral health-related quality of life (OHRQoL) among patients treated with clear aligners (CAs) versus those treated with conventional fixed orthodontics (FAs). Methods: An electronic search was performed on the database is Web of Science, Scopus, and Embase databases. Randomized and non-randomized control trials, cross-sectional, prospective cohort and retrospective trials were included. Quality was assessed with risk of bias tool and risk of bias in non-randomised studies. Meta-analyses were performed with random effects models, estimating the standardized and non-standardized mean differences, odds ratio and risk ratio as the measure of effect. The effect on time was determined using a meta-regression model. Results: Thirty one articles were included in the qualitative synthesis and 17 in the meta-analysis. CAs had a significantly lower negative impact on QoL, with an "important" effect size, while the influence of time was not significant. Periodontal indicators plaque index (PI), gingival index (GI), probing depth (PD), and bleeding on probing show significantly better values in patients treated with CAs, with moderate to large effect sizes. PI and GI have a significant tendency to improve over time. In microbiological indicators, CAs present a lower biofilm mass without differences in the percentage of patients with high counts of Streptococcus mutans and Lactobacilli bacteria. The risk of white spot lesion onset is ten times lower in carriers of CAs. Conclusions: Patients wearing CAs show better periodontal indicators, less risk of white spot development, less biofilm mass and a better QoL than patients with FAs.

• Management & Information Systems Review
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• v.30 no.1
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• pp.107-128
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• 2011

This study has two primary purposes, firstly to identify how job dissatisfaction and continuance commitment influence to creativity, secondly to explore how coworker helping and support, and perceived organizational support moderate between interaction of job dissatisfaction and continuance commitment, and creativity. The first part of the study, based on literature study on creativity, provides insight into what are antecedents and moderate variables in creativity. In the second part of the study, a comprehensive research model and hypothesis were empirically tested based on data from 322 employees in Korean organizations. The results of statistical analysis show the following. First, job dissatisfaction has positive effect on creativity. Second, interaction of job dissatisfaction and continuance commitment does not have positive effect on creativity. Third, there was not any moderating effects between interaction of job dissatisfaction and continuance commitment, and creativity in this study. The last part of this study, a theoretical and practical implication of the study, and the future research agenda are presented.

• Restorative Dentistry and Endodontics
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• v.31 no.2
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• pp.86-95
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• 2006

The purpose of this clinical study is to assess whether calcium hydroxide as an intracanal medication affects post-treatment pain in teeth especially odontogenic pain which comes from inflammation of the pulp and periradicular tissues when compared with no intracanal medication. From 213 patients who has been treated 237 root canals due to significant pain (moderate-to-severe) we recorded their age, sex, treated tooth, degree of pain, pre-operative states of the tooth. We classified patients into 2 test group; Group 1 (not gain intracanal $Ca(OH)_2$), Group 2 (gain intracanal $Ca(OH)_2$). Through the survey from the patients, we let them write down the occurrence and degree of post-treatment pain in 4hours, 2days, 7days after treatment as none, mild, moderate or severe. The followings were evaluated ; the overall incidence of flare-ups, the overall incidence of post-treatment pain in each group at each time period , the incidence of post-treatment pain in each group at each time period as related to pre-operative states of the teeth These were compared statistically with Chi-square analysis (p < 0.05). Under the condition of this investigation, no difference was observed in the incidence of post-treat-ment pain between the two groups. Therefore, $Ca(OH)_2$ as intracanal medication had no effect on preventing or decreasing the post-treatment pain.