• Ocean and Polar Research
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• 제31권3호
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• pp.247-255
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• 2009

We measured phosphate benthic fluxes and conducted phosphate adsorption experiments in order to find out the effects of adsorption on phosphate benthic fluxes in the intertidal sediments of Keunso Bay during summer and winter. Organic carbon contents showed little variation with season at St. S1, but noticeable changes were observed at St. S2, which were three times higher in winter than in summer. The higher organic carbon contents in winter resulted from the bloom of benthic algae in surface sediments. Pore water phosphate concentrations were much higher in summer than in winter. The higher phosphate concentration in summer was probably due to the faster remineralization rate of organic matter in summer. At St. S1, benthic fluxes of phosphate showed a negative value in summer and a positive value in winter. However, St. S2 had a negative benthic flux both in summer and winter. The negative benthic flux was ascribed to the phosphate adsorption on iron oxides in surface sediments. The equilibrium concentrations of phosphate obtained from the adsorption experiment were three times higher at St. S1 than at St. S2. The relatively high adsorption coefficient and low equilibrium concentration indicated that phosphate was strongly adsorbed on the surface sediments of Keunso Bay. The strong adsorption affinity significantly reduced benthic fluxes of phosphate in the intertidal sediments.

• 한국학교보건학회지
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• 제9권2호
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• pp.223-237
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• 1996

This study was conducted in order to contribute to female student health by providing fundamental data for health instruction and health counsel. The purpose of this study is to determine the frequency of PMS by a menstrual distress questionnaire, and determine sex-identity factors related to PMS. The data were collected by a questionaire conducted from December 1,1995 to December 20, 1995. The subjects of research were 1,102 high school students in Seoul. The data analyzed was done using the SPSS PC+, and the results were as follows; 1. The perceived subjective symptoms were clusted behavioral change, negative affects, pain, impaired concentration, water retention and autonomic reactions. The most common symtoms during the period of 2 to 10 days before menses were vaginal discharge(79%), back pain(70.4%), nervous tension(60.8%), fatigue(56.2%), abdominal bloating(54.5%), mood change(52.8), pelvic pain(46.8%), resistance to study(45.9) and talking(43.3). 2. There was a significant correlation between the clusters symptoms; negative affects and behavioral changes(r=.9326, p=.000), behavioral changes and impaired concentration (r=.8572, p=.000), negative affects and impaired concentration(r=.8411, p=.000) and autonomic reaction and pain(r=.7267, p=.000). 3. Sex-identity factors were related to PMS ; perception of the female(F=5.1811, p=.006) and pregnancy concerns (T=3.54, p=.000).

• The Journal of Asian Finance, Economics and Business
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• 제8권5호
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• pp.523-531
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• 2021

Vietnam's Oil and gas industry make a significant contribution to the Gross Domestic Product of Vietnam. The ongoing COVID-19 pandemic has hit every industry hard, but perhaps the one industry which has taken the biggest hit is the global oil and gas industry. The purpose of this article is to examine how the COVID-19 pandemic affects the share price of the Vietnam Oil and Gas industry. The event study method applied to Oil and Gas industry index data around three event days includes: (i) The date Vietnam recognized the first patient to be COVID-19 positive was January 23, 2020; (ii) The second outbreak of COVID-19 infection in the community began on March 6, 2020; (iii) The date (30/3/2020) when Vietnam announced the COVID-19 epidemic in the whole territory. This study found that the share price of the Vietnam Oil and Gas industry responded positively after the event (iii) which is manifested by the cumulative abnormal return of CAR (0; 3] = 3.8% and statistically significant at 5 %. In the study, event (ii) has the most negative and strong impact on Oil and Gas stock prices. Events (i) favor negative effects, events (iii) favor positive effects, but abnormal return change sign quickly from positive to negative after the event date and statistically significant shows the change on investors' psychology.

• East Asian mathematical journal
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• 제36권3호
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• pp.365-376
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• 2020

Nonalcoholic fatty liver is a type of fatty liver in which fat accumulates in the liver without alcohol. In the accumulation, Nrf1 and miR-378 genes play very important role, so called negative feedback loop, in which the two genes suppress the other's production. In other words, Nrf1 activates fatty acid oxidation which promotes fat consumption in the liver, while miR-378 deactivates fatty acid oxidation. Thus, both genes regulate nonalcoholic fatty liver. In this paper, the negative feedback loop of Nrf1 and miR-378 are expressed by a system of ordinary differential equations. And, bifurcation simulation shows the change in the amount of each gene with significant parameter range changes. Bifurcation simulation has also used to determine the thresholds for transit between disease and steady state.

• International Journal of Control, Automation, and Systems
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• 제1권4호
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• pp.453-458
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• 2003

The anomaly-detection algorithm based on negative selection of T cells is representative model among self-recognition methods and it has been applied to computer immune systems in recent years. In immune systems, T cells are produced through both positive and negative selection. Positive selection is the process used to determine a MHC receptor that recognizes self-molecules. Negative selection is the process used to determine an antigen receptor that recognizes antigen, or the nonself cell. In this paper, we propose a novel self-recognition algorithm based on the positive selection of T cells. We indicate the effectiveness of the proposed algorithm by change-detection simulation of some infected data obtained from cell changes and string changes in the self-file. We also compare the self-recognition algorithm based on positive selection with the anomaly-detection algorithm.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.179-187
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• 2022

The project performances can be measured in terms of meeting the project schedule, budget, and conformance to functional and technical specifications. Numerous studies have been conducted to examine the causes and effects of change orders for both vertical and horizontal construction, respectively. However, these studies mainly focus on a single project type, so this paper examines the impact of change order for cost growth and schedule overruns using four different building types to close the gap in the change order research area. A total of 211 building projects are collected from four building types: healthcare, residential, office, and education. Statistical analyses using ANOVA tests and linear regression models are used to examine the created metric $CO/day on the cost and schedule impacts. The results found that mean $CO/day values were not statistically different among building types, and that the sum of change orders is a statistically significant predictor of $CO/day. The results will help project stakeholders mitigate the negative change orders effects can be a challenge for project managers and researchers alike.

• Journal of Preventive Medicine and Public Health
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• 제40권3호
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• pp.218-226
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• 2007

Objectives : This study examined the relationship of parent-related negative life events with mental health and delinquent behaviors among Korean adolescents. Methods : A total of 2,976 high school first-grade pupils (1,498 boys & 1,478 girls) taking part in the third wave of Korean Youth Panel Survey completed a self-administered questionnaire regarding parent-related life events, depressive feelings, suicidal ideation, delinquent behaviors, demographic characteristics, parental socioeconomic status, social support, and social capital. Data analyses were conducted using multivariate logistic regression. Results : After adjusting for all covariates, the more parent-related negative life events adolescents experienced throughout their whole life, the more likely adolescent were to have mental and behavioral problems. A significant dose-response relationship between them was more clearly observed in girls than in boys. The experience of parentrelated negative events during childhood was significantly associated with suicidal ideation and delinquent behaviors for boys, and with depressive feelings for girls during adolescence. Indeed, parental social support, social capital, and having a close friend with delinquent behaviors, especially for girls, partially mediated the relationship between parent-related negative life events and both outcomes. Conclusions : The study showed a clear dose-response relationship of frequency of parent-related negative life events with poor mental and behavioral health for both genders. The residual effect of being exposed to parent-related events during childhood on mental health and delinquent behaviors during adolescence still remained.

• 한국보육지원학회지
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• 제17권4호
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• pp.73-91
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• 2021

Objective: This study focused on the relationships between emotionality, social competence and play behavior in a sample of 218 4- to 5-year olds attending daycare centers. Methods: All variables were measured by the daycare teachers of the surveyed children. The data were analyzed using Simple Regression and Multiple Regression through SPSS Win 25.0. Results: First, preschoolers' positive emotionality had a negative effect on their play disruption and play disconnection and a positive effect on play interaction. On the other hand, their negative emotionality had a positive effect on play disruption and play disconnection and a negative effect on play interaction. Second, their positive emotionality had a positive influence on social competence and their negative emotionality had a negative influence. Finally, the effect of their positive emotionality on play disruption was partially mediated, and their play disconnection and play interaction was totally mediated by social competence. On the other hand, the effect of preschoolers' negative emotionality on play disruption and play disconnection was totally mediated, and their play interaction was partially mediated by social competence. Conclusion/Implications: The results of this study imply that we need to help preschoolers promote emotionality and social competence together to change their play behavior positively.

• Asian-Australasian Journal of Animal Sciences
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• 제11권4호
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• pp.441-444
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• 1998

The negative direct-maternal genetic correlation $(r_{dm})$ for weaning weight is inflated when data are analyzed with model ignoring sire-by-year interactions (SY). An analytical study investigating the consequences of ignoring SY was undertaken. The inflation of negative correlation could be due to a functional relationship of design matrices for additive direct and maternal genetic effects to that for sire effects within which SY effects were nested. It was proven that the maternal genetic variance was inflated by the amount of reduction for sire variance; the direct genetic variance was inflated by four times the change for maternal genetic variance; and the direct-maternal genetic covariance was deflated by twice the change for maternal genetic variance. The findings were agreed to the results in previous studies.

• 가정과삶의질연구
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• 제17권3호
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• pp.47-62
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• 1999

The purpose of this study was to investigate the problem coping strategies and depression of unemployed husband's wives and to analysis the social support(education and counseling program) needs for their psychological adjustment. The subjects were 139 unemployed husband's wives living in Seoul city and Kyungi-do province. The questionnaire method was used for data gathering. The major findings were as follows" 1) Wives perceived the most negative change of unemployed husband. Wives' depression was influenced by self-esteem evaluation of husband's coping behavior weak health passive coping strategies and negative change of husband and marital relation. 2) Wives needed education and counseling support the most in the area stress & mental health problem marital conflict and marital communication. The result of this study were discussed in the relation with the contents of education and counseling program for unemployed husbands' wives.