• Korean Journal of Materials Research
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• v.28 no.10
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• pp.544-550
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• 2018

The passivation of AZ91D Mg alloys by plasma anodization requires deliberate choice of process parameters due to the presence of large amounts of structural defects. We study the dependence of pore formation, surface roughness and corrosion resistance on voltage by comparing the direct current (DC) mode and the pulse wave (pulse) mode in which anodization is performed. In the DC plasma anodization mode, the thickness of the electrolytic oxide film of the AZ91D alloy is uneven. In the pulse mode, the thickness is relatively uniform and the formed thin film has a three-layer structure. The pulse mode creates less roughness, uniform thickness and improved corrosion resistance. Thus, the change of power mode from DC to pulse at 150 V decreases the surface roughness (Ra) from $0.9{\mu}m$ to $0.1{\mu}m$ and increases the corrosion resistance in rating number (RN) from 5 to 9.5. Our study shows that an optimal oxide film can be obtained with a pulse voltage of 150 V, which produces an excellent coating on the AZ91D casting alloy.

• Geomechanics and Engineering
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• v.14 no.5
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• pp.453-458
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• 2018

Geomechanical parameters are important factors for engineering projects during design, construction and support stages of tunnel and dam projects. Geostatistical estimation methods are known as one of the most significant approach at estimation of Geomechanical parameters. In this study, Azad dam headrace tunnel is chosen to estimate Geomechanical parameters such as Rock Quality Designation (RQD) and uniaxial compressive strength (UCS) by ordinary kriging as a geostatistical method. Also Rock Mass Rating (RMR) distribution is presented along the tunnel. Main aim in employment of geostatistical methods is estimation of points that unsampled by sampled points.To estimation of parameters, initially data are transformed to Gaussian distribution, next structural data analysis is completed, and then ordinary kriging is applied. At end, specified distribution maps for each parameter are presented. Results from the geostatistical estimation method and actual data have been compared. Results show that, the estimated parameters with this method are very close to the actual parameters. Regarding to the reduction of costs and time consuming, this method can use to geomechanical estimation.

• Journal of Korean Academy of Nursing Administration
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• v.13 no.3
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• pp.345-351
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• 2007

Purpose: The purpose of this study was to identify the relationship between patient characteristics and patient satisfaction. Methods: A cross-sectional questionnaire survey was conducted in an acute care hospital. The subjects were 317 patients discharged from general medical and surgical nursing care units during September, 2005. Patient satisfaction was measured using the short-form satisfaction scale of Hwang and Park(2001). Additional information about patient characteristics, including general demographics and health care utilization variables, was collected from the hospital information systems. Multiple regression analysis was performed to determine patient characteristics influencing patient satisfaction. Results: Patients were satisfied with hospital care with an average of 4.10 on a five-point Likert scale. Patient characteristics explained 13.5% of the variance of patient satisfaction. The significant factors influencing patient satisfaction were patients' age and perceived health status. There was no significant relationship between structural variables and patient satisfaction. Conclusion: This study showed that patients' characteristics were significant factors explaining patient satisfaction. Therefore, these characteristics should be adjusted in reporting patient satisfaction as an indicator for hospital-level or department-level rating.

• Journal of the Korean Home Economics Association
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• v.50 no.1
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• pp.103-119
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• 2012

The purpose of this study was to explore the mediating effects of preschooler's effortful control on the relationship between maternal emotional availability and preschooler's social skills and problem behaviors. One hundred-thirty six 5-year-old preschoolers and their mothers participated in this study. Instruments for this study were the Emotional Availability Scale for maternal emotional availability, the Delay task, and the Child Behavior Questionnaire for preschooler's effortful control, and the Social Skill Rating Scale, K-CBCL 1.5-5 and K-TRF for preschooler's social skills and problem behaviors. The resulting data were analyzed using descriptive statistics, partial correlation, and structural equation modeling analysis. As predicted, the preschooler's effortful control mediated the effects of maternal emotional availability on preschooler's social skills and problem behaviors. In conclusion, the preschooler's effortful control mediates the effects of emotion related socialization behavior on the preschooler's socio-emotional adjustment.

• The Journal of Korean Academic Society of Nursing Education
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• v.7 no.2
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• pp.379-390
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• 2001

The purpose of this study was to examine the actual condition of the adolescent status delinquency and to predict that family environments, the mother's rear attitudes and personal factors influence on the adolescent status delinquency among high school students in Busan(N=404). Under these purposes of the study, the preliminary study was performed to divided the criminal delinquency from the status delinquency, and on the basis of the result of the preliminary study, the analysis of causal pathway were performed. The data were surveyed using paper and pencil self-rating. Descriptive statistics and pathway analyses were conducted to answer research objectives. The result of this study was as follows. First, the status delinquency and the criminal delinquency are different dimensions with each other independently. Second, Contents of the status delinquencies were Drinking, Smoking, Cheating examination, Stopping out, Reckless running, Gang fighting, Reading lewdness and Watching lewd video, Sexual intercourse with the other gender, etc., The criminal delinquencies were Robbing of bicycle or auto-bicycle, Taking nalcotic drug, Robbing money of drunkard and women, Rape, Setting on fire, etc. Third, The factors of structural environments of the family and the factors of mother's rear attitude influenced on the status delinquency via adolescence's compulsivity. that is to say, if the mother's rear attitude is affective, it restrains the impulsivity of adolescence causing to the restraint of the status delinquency.

• Computers and Concrete
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• v.7 no.3
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• pp.249-269
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• 2010

Managing and reusing knowledge in engineering and construction sectors can lead to greater competitive advantage, improved designs, and more effective management of constructed facilities. The use of Information Technology (IT) in design and construction can exploit strategic opportunities for new ways of integration, sharing and facilitating information and knowledge in any field of engineering. The integrating of separate areas of IT can be used to bring a group of experts and specialists in any field of engineering closer together by allowing them to communicate and exchange information and expertise that facilitate knowledge capture, sharing, and reuse. A lack of an advisory management system and a need to marshal all available data in a common format has indicated the need for an integrated engineering computing environment to investigate concrete repair problems. The research described in this paper is based upon an evaluation management system (EMS) which comprising a database management system (REPCON) alongside visualisation technologies and evaluation system (ECON) is developed to produce an innovative platform which will facilitate and encourage the development of knowledge in educational, evolution and evaluation modes of concrete repair. This allows us to create assessment procedures that will allow the current condition of the concrete structure and its components to be expressed numerically using a confidence level (CL) so as to take the best course of action in the repair and maintenance management. The explained rating system, which is related to structural integrity and serviceability of the structure, allows the confidence level to be determined by visual inspection and the descriptive information and pictures taken from an available REPair of CONcrete (REPCON) database.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.6
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• pp.91-99
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• 2004

Most of LV customer have applied the 3-phase four wire system distribution system because it has advantage of supplying both of 1-phase at 3-phase loads simultaneously. Due to its structural simplicity, it is more convenient for use rather than the conventional separated scheme. But once in a while uneven load unbalance or unclean power quality lead some problems such as do-rating or power losses. In this paper, voltage and current waveform in the actual fields have been measured and analyzed in relation with intermationally allowable voltage unbalance limits.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.26 no.4
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• pp.64-75
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• 2018

A status of air traffic controller is a government officer and air traffic controllers who work at airport are divided by duty rating and work experience. Abiding by law, rules and regulation, air traffic controllers are working together based on mutual trust. This paper's theoretical background is based on cultural bias theory. The theory divide people group into four groups according to cultural bias such as fatalism, hierarchy, individualism and egalitarianism. A research model was designed how such four cultural bias could affect air traffic controller's risk response in case of emergency or abnormal situation during their work. Depend on empirical research, it was found that air traffic controllers perceived they had been more biased to fatalism than hierarchy. The characteristics of fatalism group are as follows: first of all, they follow rigid rules and regulation. However, they have less self-efficacy compared to other government officers. According to structural equation model, air traffic controller's fatalism had a significant negative effect on organizational royalty. Their royalty, however, had a very significant positive effect on planning response and immediate response.

• Structural Monitoring and Maintenance
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• v.8 no.4
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• pp.361-378
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• 2021

While the pavement rating system is being utilized for periodic road condition assessment in the Eastern Region municipality of Saudi Arabia, the condition assessment is costly, time-consuming, and not comprehensive as only few parts of the road are randomly selected for the assessment. Thus, this study is aimed at developing a condition assessment model for a specific sample of a residential road network in Dammam City based on an individual road and a road network. The model was developed using the Analytical Hierarchy Process (AHP) according to the defect types and their levels of severity. The defects were arranged according to four categories: structure, construction, environmental, and miscellaneous, which was adopted from sewer condition coding systems. The developed model was validated by municipality experts and was adjudged to be acceptable and more economical compared to results from the Eastern region municipality (Saudi Arabia) model. The outcome of this paper can assist with the allocation of the government's budget for maintenance and capital programs across all Saudi municipalities through maintaining road infrastructure assets at the required level of services.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.1
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• pp.61-71
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• 2010

The attributes related to the health condition of RC deck slabs are analyzed to help us identify and rate the safety level of the bridges in this study. According to the related reports the state assessment for the outward aspects of bridges is the important and critical part for rating the overall structural safety. In this respect, the careful identification for the various state attributes make the field inspection and structural diagnosis very effective. This study analyzes the influence of the state attributes on evaluation classes and the relationship of them by the inductive reasoning, which raise the understanding and performance for evaluation work, and support the logical approach for the state assessment. ID3 algorithm applied to the case set which is constructed from the field reports indicates the main attributes and the precedence governing the assessment, and derives the decision hierarchy for the state assessment.