• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.2717-2726
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• 2013

This study was conducted in order to analyze the theories behind external protective factors. In particular, it sought to understand the influence of adolescent resilience on learning motivation. Students of a public high school located in Gyeonggi Province participated in various questionnaires during the week of March 5th, 2013. Frequency analysis, one-way ANOVA (analysis of variance), correlation analysis, and multiple regression analysis were utilized to analyze the acquired data. The results revealed that when family relationships were strong and local community expectations were high, the students' 'attention to implementation processes,' one aspect of intrinsic motivation to learn, was also high. 'Suitable levels of adventurousness and risk-taking,' another aspect of intrinsic motivation to learn, was high when school expectations were also high and when relationships at the school level were weaker. The study results verified that the theory that intrinsic motivation to learn can be enhanced by strengthening external factors to protect adolescent resilience. This study is significant in that it establishes theoretical grounds to address adolescent issues, to develop programs to prevent school dropouts, and to apply the results to future legislative policies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2131-2139
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• 2013

This study clearly identify the correlation between adolescents resiliency and suicidal ideation and more effective to strengthen the external protective factors for adolescents suicide prevention alternatives presented. Research subjects were 243 boy and girl first year students in a high school located in Kyunggi Province; Questionnaires were distributed for one week from March 5, 2013. Frequency analysis, correlation analysis, multiple regression analysis, t-test, one-way ANOVA, etc. were executed. All empirical tests were verified with 5% of significance level. From the result of analysis, suicidal ideation has a negative correlation with the adolescent resilience, and especially, when interaction in family dimension and the care, expectation level of school and peer dimension become higher, suicidal ideation was reduced. The implications of this study suggest that the material prepared for suicide prevention policy based on the results of a study on the impact of adolescents resiliency to suicidal ideation.

• Korean Journal of Childcare and Education
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• v.8 no.1
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• pp.25-44
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• 2012

The purpose of this study was to conduct a systematic review of the previous studies done on the child-care teacher's turnover intentions. From 2001 to 2011, 33 articles which reforted primary empirical data met the criteria for inclusion in the meta-analysis. The results of this study are as follo ws: First, included in the main factors related to child-care teachers' turnover intentions were a job-related variable, an organizational internal variable and an organizational external variable. Second, the most influential protective variable related to the child-care teacher's turnover intentions among the set of organizational external variables was work-time followed by welfare, education and training, remuneration, social recognition and promotion system. Third, the most influential protective variable related to child-care teachers' turnover intentions among the set of job-related variables was teacher efficacy followed by job satisfaction, participation of decision making, performance, work-autonomy and work-professionalism. Fourth, the most influential protective variable related to the child-care teacher's turnover intentions among the set of organizational internal variables was personal relations followed by relationships with the director and relationships with colleagues. The effect size of these variables was large. Fifth, the results of meta-regression analysis revealed that the survey area and years had no significant effect on overall effect sizes.

• Korean Journal of Social Welfare
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• v.55
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• pp.255-281
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• 2003

This study sought to explore factors affecting the adjustment of children living in shelters for battered women. Specifically, the impact of domestic violence on children's internal and external adjustment was examined using data from two samples: children who were exposed to marital violence and those who did not have violent experience. Likewise, this study identified the variables that distinguished the "resilient" children from the maladjusted group. The pathways by which protective factors considerably affected children's adjustment were also investigated. A total of 72 children in a women's shelter and their mothers and 76 children in nonviolent homes and their mothers were considered. ANOVA, logistic regression models, and path analysis were employed to process the data. Results revealed that children of battered women demonstrated a high frequency of aggressive and delinquent behaviors and had poor academic achievement and depressive mood compared to children coming from nonviolent homes. Likewise, children who were exposed to marital violence and were physically abused themselves were more likely show aggressive or delinquent behaviors compared to those who only witnessed marital violence. In addition, social support was found to be a protective factor in academic achievement. Predictors of delinquent behavior included the mother's education and income as well as the children's age and social support. Factors related to children's self-esteem included the social support and the mother's self-esteem. Moreover, woman battering has a direct effect on children's adjustment as well as indirect effect through children's academic achievement and self-esteem. Finally, woman battering indirectly affected children's academic achievement through the mother's depression or the child's social support. Based on these findings, practical implications of enhancing children's adjustment were discussed.

• Journal of Mechanical Science and Technology
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• v.18 no.4
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• pp.592-596
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• 2004

Corrosion is never avoided in the use of materials with various environments. The underwater hull is normally protected against rusting by several coatings of anti-corrosive paint. The purpose of ICCP(Impressed Current Cathodic protection) system is to eliminate the rusting or corrosion, which occurs on metal immersed in seawater. The anode of ICCP system is controlled by an external DC source with converter. The function of anode is to conduct the protective current into seawater. The proposed algorithm includes the harmonic suppression control strategy and the optimum protection strategy and has tried to test the requirement current density for protection, the influence of voltage, the protection potential. This paper was studied the variation of potential and current density with environment factors, time and velocity, and the experimental results will be explained.

• Korean Journal of Health Education and Promotion
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• v.22 no.4
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• pp.137-154
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• 2005

Objectives: This study aims to examine the positive effects of developmental assets on the prevention of health risk behaviors among Korean adolescents. The framework of developmental assets was introduced as building blocks for healthy child and adolescent development by Benson and his colleagues. These assets represent positive external environmental factors and internal personal qualities which strongly influence the quality of life of adolescents. Methods: In 2001, we administered self-reported questionnaires to 3,739 girls and boys in grade 9 at eight schools in two cities, Chinju and Suwon in South Korea. The data was compiled into a 'Korean Youth Health Related Behaviors and Developmental Assets Survey' and then analyzed Youth health risk behaviors, which we measured in terms of their frequency, included tobacco, alcohol, and substance use, sexual intercourse, anti-social behaviors, violence, feelings of social isolation at school, depression or attempted suicide, absenteeism from school, gambling. Results: Overall, with respect to developmental assets, the Korean adolescents surveyed only 12.6 of the 40 assets, and 88 percent of adolescents had 20 or fewer of the assets. Based on their number of developmental assets(DA), adolescents were categorized into four groups: Group I(DA 0-10): Group II(DA 11-20): Group III(DA 21-30): Group IV(DA 31-40). We examined the differences in the frequency of each health risk behavior across the four groups, Group I-IV, and found that the frequency of most health risk behaviors decreased as the number of developmental assets increased. Conclusion: We therefore concluded that in order to make effective approaches for the prevention of health risk behaviors among adolescents, we should consider and develop more comprehensive and adolescents-based policy and programs to promote various aspects of adolescents' health and quality of life.

• Corrosion Science and Technology
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• v.15 no.6
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• pp.271-280
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• 2016

An approach to achieving the ambitious goal of cost effectively extending the safe operation life of energy pipeline to 100 years is the application of health monitoring and life prediction tools that are able to provide both long-term remnant pipeline life prediction and in-situ pipeline condition monitoring. A critical step is the enhancement of technological capabilities that are required for understanding and quantifying the effects of key factors influencing buried steel pipeline corrosion and environmentally assisted materials degradation, and the development of condition monitoring technologies that are able to provide in-situ monitoring and site-specific warning of pipeline damage. This paper provides an overview of our current research aimed at developing new sensors and electrochemical cells for monitoring, categorising and quantifying the level and nature of external pipeline and coating damages under the combined effects of various inter-related variables and processes such as localised corrosion, coating cracking and disbondment, cathodic shielding, transit loss of cathodic protection.

• Computers and Concrete
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• v.19 no.4
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• pp.413-417
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• 2017

Concrete is a material popularly used in construction. Due to the load-bearing and external environmental factors during utilization or manufacturing, its surface is prone to flaws, such as crack and leak. To repair these superficial defects and ultimately and avoid the deterioration of the concrete's durability, numerous concrete surface protective coatings and crack repair products have been developed. Currently, studies are endeavoring to exploit the mineralization property of microbial strains for repairing concrete cracks be the repairing material for crack rehabilitation. This research aims to use bacteria, specifically B. pasteurii, in crack rehabilitation to enhance the flexural and compression strength of the repaired concrete. Serial tests at various bacterial concentrations and the same $Urea-CaCl_2$ medium concentration of 70% for crack rehabilitation were executed. The results prove that the higher the concentration of the bacterial broth, the greater the amount of calcium carbonate precipitate was induced, while using B. pasteurii broth was for crack rehabilitation. The flexural and compression strengths of the repaired concrete test samples were the greatest at 100% bacterial concentration. Compared to the control group (bacterial concentration of 0%), the flexural strength had increased by 32.58% for 1-mm crack samples and 51.01% for 2-mm crack samples, and the compression strength had increased by 28.58% and 23.85%, respectively. From the SEM and XRD test results, a greater quantity of rectangular and polygonal crystals was also found in samples with high bacterial concentrations. These tests all confirm that using bacteria in crack rehabilitation can increase the flexural and compression strength of the repaired concrete.

• Journal of Magnetics
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• v.16 no.1
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• pp.36-41
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• 2011

If gas is leaking out of gas pipelines, it could cause a huge explosion. Accordingly, it is important to ensure the integrity of gas pipelines. Traditionally, over the years, gas-operating companies have used the ILI system, which is based on axial magnetic flux leakage (MFL), to inspect the gas pipelines. Relatively, there is a low probability of detection (POD) for the axial defects with the axial MFL-based ILI. To prevent the buried pipeline from corrosion, it requires a protective coating. In addition to the potential damage to the coating by environmental factors and external forces, there could be defects on the damaged coating area. Thus, it is essential that nondestructive evaluation methods for detecting axial defects (axial cracks, axial groove) and damaged coating be developed. In this study, an electromagnetic acoustic transducer (EMAT) sensor was designed and fabricated for detecting axial defects and coating disbondment. In order to validate the performances of the developed EMAT sensor, experiments were performed with specimens from axial cracks, axial grooves, and coating disbondment. The experimental results showed that the developed EMAT sensor could detect not only the axial cracks (minimum 5% depth of wall thickness) and axial grooves (minimum 10% depth of wall thickness), but also the coating disbondment.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4146-4158
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• 2022

Ultra-high performance concrete (UHPC) has been widely utilized in military and civil protective structures to resist intensive loadings attributed to its excellent properties, e.g., high tensile/compressive strength, high dynamic toughness and impact resistance. At present, aiming to improve the defects of the traditional vertical concrete cask (VCC), i.e., the external storage facility of spent fuel, with normal strength concrete (NSC) shield, e.g., heavy weight and difficult to fabricate/transform, the feasibility of UHPC applied in the shield of VCC is numerically examined considering its high radiation and corrosion resistance. Firstly, the finite element (FE) analyses approach and material model parameters of NSC and UHPC are verified based on the 1/3 scaled VCC tip-over test and drop hammer test on UHPC members, respectively. Then, the refined FE model of prototypical VCC is established and utilized to examine its dynamic behaviors and damage distribution in accidental tip-over and end-drop events, in which the various influential factors, e.g., UHPC shield thickness, concrete ground thickness, and sealing methods of steel container are considered. In conclusion, by quantitatively evaluating the safety of VCC in terms of the shield damage and vibrations, it is found that adopting the 300 mm-thick UHPC shield instead of the conventional 650 mm-thick NSC shield can reduce about 1/3 of the total weight of VCC, i.e., about 50 t, and 37% floor space, as well as guarantee the structural integrity of VCC during the accidental drop simultaneously. Besides, based on the parametric analyses, the thickness of concrete ground in the VCC storage site is recommended as less than 500 mm, and the welded connection is recommended for the sealing method of steel containers.