• Journal of Ocean Engineering and Technology
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• v.11 no.2
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• pp.77-90
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• 1997

Wave deformation due to Oscillating water column (OWC) plant was studied. To solve this problem, three dimensional numerical method based on Improved Green integral equation was applied. Method condition was considered as well as fixed condition and freely floating condition. From the calculation results, main characteriatic of wave deformation due to OWC plant were discussed. Also, some calculations for the floating barge were performed to confirm the validity of numerical solution of the method.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.399-402
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• 2002

Industrial wastewater with high ammonium concentration was treated in batch biological systems which was a modified Ludzack- Ettinger process. Up to 78% conversion of $NH_4\;^+-N$ to $NO_x\;^--N$ was achieved in batch culture condition. Under anoxic condition with methanol as the carbon source, the denitrifiers decreased $NO_x\;^--N$ concentration from 608 mg/L to 5.6 mg/L in 22 d. As well as anoxic denitrification of $NO_x\;^-$ to $N_2$, dissimilatory nitrate reduction to ammonium also occurred under the condition as respiratory denitrification.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.698-703
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• 2000

In a computational fluid dynamics, the imposition of open boundary condition has an important part of the accuracy but it is not easy to find the optimal boundary rendition. This difficult is introduced by making artificial boundary in unbounded domairs. Such open boundary requires us to ensure the continuity of all primitive variables because the nature is in continuum. Here we introduce a revised well-conditioned open boundary condition particularly in FEM and apply it to various problems-entrainment, body force, short domains.

• Journal of the Korean GEO-environmental Society
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• v.23 no.2
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• pp.25-36
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• 2022

In this study, seepage control effect of relief well was evaluated quantitatively on embankment of small fill dam and levee. Seepage analysis of dam and levee were carried out according to the permeability of fill material and foundation and to analyze behaviour characteristics of seepage. The up-lift pressure at toe of embankment was analyzed which is generated by seepage according to relief well installation condition. The relief well could reduce pore water pressure which is to cause piping or up-lift pressure at foundation ground of embankment and it does not be influenced on geometric condition such as dam height and slope incline. In case of relative low permeable ground, the pore water pressure reduction effect of relief well was decreased compare with high permeable ground but it shows pore water pressure reduction effect compare with no relief well condition. The reduction effect of relief well shows relative gap according to diameter and penetration length of relief well and the installation length of relief well is the most effective factor for seepage control.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.2
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• pp.106-113
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• 2000

This study describes how a properly calibrated simulation method could be used to investigate the latchup immunity characteristics among the various high energy ion implanted CMOS twin well (retro-grade/BILLI/BL) structures. To obtain the accurate quantitative simulation analysis of retrograde well, a global tuning procedure and a set of grid specifications for simulation accuracy and computational efficiency are carried out. The latchup characteristics of BILLI and BL structures are well predicted by applying a calibrated simulation method for retrograde well. By exploring the potential contour, current flow lines, and electron/hole current densities at the holding condition, we have observed that the holding voltage of BL structure is more sensitive to the well design rule (p+to well edge space /n +to well edge space) than to the retrograde well itself.

• Journal of Korean Society for Quality Management
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• v.41 no.1
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• pp.109-118
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• 2013

Purpose: Given the several proper models for given mixture components-process variables experimental data, we propose a strategy to find the optimal condition in which the performance of the responses is well-behaved under those models. Methods: Given the mixture experimental data with process variables, first we choose the reasonable starting models among the class of admissible product models based on the model selection criteria and then, search for the candidate models that are the subset models of the starting model by the sequential variable selection method or all possible regressions procedure. Good candidate models are screened by the evaluation of model selection criteria and checking the residual plots for the validity of the model assumption. Results: We propose a strategy to find the optimal condition in which the performance of the responses is well-behaved under those good candidate models by adopting the optimization methods developed in multiple responses surface methodology. Conclusion: A strategy is proposed to find the optimal condition in which the performance of the responses is well-behaved under those proper combined models. This strategy to find the optimal condition is illustrated with the example in this paper.

• Korean Journal of Health Education and Promotion
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• v.19 no.1
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• pp.109-132
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• 2002

The study surveyed 1,127 mothers whose children aged 3 to 5 went to 25 randomly selected kindergartens, which were located in Busan Metropolitan City and the adjacent Gimhae City, and analyzed the preventive health behaviors on their children and the condition of home health education on their children. As the compulsory kindergarten education will e to be implemented within 4 years, this study aimed to draw up the rudimentary material for health education at kindergartens. The study results are summed up as follows: 1. Mothers' awareness of health-related attitude and behavioral level for their children at kindergarten: 1) The general health condition of the children, which mothers are aware of, was that they were healthy on the whole. As their children becomes older, the income level of the parents is lower, and mothers have lower level of educational standard, the health condition of the children was found a little lower. 2) In terms of mothers' recognition of the practice level of preventive health behaviors, the items such as going to bed regularly, washing hands and feet well, and having meals regularly were high in the practice level, while exercise and tooth-brushing were not practiced well. 2. The condition of mothers' health education of their children: 1) It was found that washing hands and feet, restriction of overeating and preference for specific kinds of food, guidance on regular sleep and regular meal were practiced well among items of home health education targeting kindergarten children. 2) Mothers have obtained information on family health from printed matter such as newspaper or magazine rather than the visual media. 3) From the cross analysis of mothers' health education on children and children's health behaviors, as the standard of education of mothers was higher, so was the level of preventive health behaviors of children. 3. From the result of multi regression analysis of the factors influencing the preventive hygiene of kindergarten children, it was found that as the home health education level was higher, so was the health behavior of children. On the other hand, as the mothers were older, the health behavior of children became lower.

• Journal of the Korea Convergence Society
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• v.10 no.1
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• pp.329-338
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• 2019

The purpose of this study was conducted to investigate the relationship among working conditions, health status and well-being of door to door deliverers as well as to identify the factors influencing well-being. Study participants of 248 door to door deliverers were collected from the 2014 Korean Working Conditions Survey. Data were analyzed using the SPSS 24.0 statistical program. As a results, the factors influencing well-being of door to door deliverers were musculoskeletal work-related risk, working condition satisfaction, work life balance, and subjective health status and these variables explained 23.9% of well-being. Based on these findings, programs that develop working condition and health status are necessary for door to door deliverers to well-being.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.258-265
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• 2013

This study was designed to investigate the correlation between the degree of knowledge in regards to the importance of oral health and the smile scores as well as the correlation between their actual oral conditions and smile scores. The author surveyed the knowledge and the actual oral health condition of the subjects, 150 high school students (80 males and 70 females), and their frontal pictures were taken when they had full smiles. After evaluation of the smiles of the subjects by five dentists, the results were analysed. This study showed that there was neither a correlation between the smile score and the knowledge of oral health nor the actual oral condition. The investigation showed that the actual oral condition and care was performed well even if there were some wrong answers in the questionnaire, which asked about proper oral health. In conclusion, the smile could be related to the repetition of the habit of smiling rather than being related to the knowledge of oral health or their actual oral condition.

• The Journal of Information Systems
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• v.28 no.4
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• pp.1-25
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• 2019

Purpose The purpose of this study is to investigate cognitive mechanism of goal relations (Single-goal vs. Multiple-goals) and to-do list (Packing vs. Unpacking) and also verify the role of self-efficacy in the perspective of motivation belief. The perspective of cognitive mechanism is related to the effects of how the relations of multitasking environments affects to facilitating relation or conflicting relations. In pursuit of a single goal, judgement of task importance can be facilitated by unpacking effect due to relations of strongly associated project components including to-do list. On the other hands, in pursuit of multiple goals, judgement of task importance can be conflicted due to mutually exclusive relations of multiple goals. Additionally, the cognitive mechanism can be regulated from the role of self-efficacy, which contributes to motivation belief on how much a person is confident in achieving given tasks. In the end this research is to identify self-efficacy as boundary condition in inhibiting the effects of facilitation and conflict. Design/methodology/approach This study conducted Two-way ANOVA (Packing/ Unpacking * Single-goal/ Multiple-goals) to explore the effects of cognitive mechanism on task importance. After that we performed Three-way ANOVA, 2 (To-do list: Packing/ Unpacking) * 2 (Goal relation: Single-goal/ Multiple-goals) * 2 (Self-efficacy: Low self-efficacy/ High self-efficacy) to verify the role of self-efficacy between goal relations and to-do list. Findings In the cognitive mechanism, the task importance is not significantly different between in packed and in unpacked condition in pursuit of a single goal. But multitasking with multiple goals causes goal conflict, which means packed condition indicates significantly higher task importance than unpacked condition. Additionally, for a group with low self-efficacy unpacking leads to conflicting relation, which implies that packed condition is more efficient strategy than packed condition. On the other hands, in pursuit of mulitple goals, either packing or unpacking has no distinctive effects on task importance. However, participants with high self-efficacy are no longer affected by facilitating relation and conflicting relation as well in pursuit of either a single goal or multiple goals as well.