• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.7.1-7.8
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• 2020

Maxillomandibular advancement (MMA) is effective for the treatment of obstructive sleep apnea (OSA). In previous studies, the airway was increased in the anteroposterior and transverse dimensions after MMA. However, the effect of the opposite of mandibular movement (mandibular setback) on the airway is still controversial. Mandibular setback surgery has been suggested to be one of the risk factors in the development of sleep apnea. Previous studies have found that mandibular setback surgery could reduce the total airway volume and posterior airway space significantly in both the one-jaw and two-jaw surgery groups. However, a direct cause-and-effect relationship between the mandibular setback and development of sleep apnea has not been clearly established. Moreover, there are only a few reported cases of postoperative OSA development after mandibular setback surgery. These findings may be attributed to a fundamental difference in demographic variables such as age, sex, and body mass index (BMI) between patients with mandibular prognathism and patients with OSA. Another possibility is that the site of obstruction or pattern of obstruction may be different between the awake and sleep status in patients with OSA and mandibular prognathism. In a case-controlled study, information including the BMI and other presurgical conditions potentially related to OSA should be considered when evaluating the airway. In conclusion, the preoperative evaluation and management of co-morbid conditions would be essential for the prevention of OSA after mandibular setback surgery despite its low incidence.

• Korean Journal of Childcare and Education
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• v.19 no.4
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• pp.29-52
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• 2023

Objective: This research aims to examine the effect of a young children's engineering-focused STEAM program based on the project approach - a program that constructs components aligned with children's interests in their play through an engineering design process - on their scientific inquiry ability, mathematical problem-solving ability, and creativity. Methods: In this research, 42 five-year-old children from a public kindergarten in S district, I city, were randomly divided into experimental and comparative groups, each with 21 children. The engineering-focused STEAM program was conducted from April 18 to June 10, 2022, with the experimental group exploring the 'car' theme and the comparison group focusing on a different theme. The study employed an independent sample t-test and analysis of covariance(ANCOVA), using the pretest as a covariate to control variables. Results: The children-selected 'cars' themed engineering-focused STEAM program was effective in enhancing their scientific inquiry ability, mathematical problem-solving ability and creativity. Conclusion/Implications: The engineering-focused STEAM program, which emerges from young children's interesting daily play, had positive effects on enhancing their scientific inquiry ability, mathematical problem-solving ability, and creativity. This research can serve as fundamental data for developing education programs focused on engineering within the STEAM framework, guided by children's emergent play.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.11
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• pp.3083-3098
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• 2023

As demands for efficient and echo-friendly production of marine products increase, smart aquaculture based on information and communication technology (ICT) has become a promising trend. The smart aquaculture is expected to control fundamental farm environment variables including water temperature and dissolved oxygen (DO) levels with less human intervention. A recirculating aquaculture system (RAS) is required for the smart aquaculture which utilizes a purification tank to reuse water drained from the water tank while blocking the external environment. Elaborate water treatment should be considered to properly operate RAS. However, analyzing the water treatment performance is a challenging issue because fish farm circumstance continuously changes and recursively affects water fluidity. To handle this issue, we introduce computational fluid dynamics (CFD) aided water treatment analysis including water fluidity and the solid particles removal efficiency. We adopt RAS parameters widely used in the real aquaculture field to better reflect the real situation. The simulation results provide several indicators for users to check performance metrics when planning to select appropriate RAS without actually using it which costs a lot to operate.

• East Asian Journal of Business Economics (EAJBE)
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• v.12 no.2
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• pp.43-50
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• 2024

Purpose: The present study investigates if the type of organizational culture influences the level of job-related stress. This study is significant because creating the need to explore the concept to become more informed on the best practices to promote and foster a positive culture that prioritizes workers, it could result in a healthier workforce, improved organizational performance, and success. Research design, data and methodology: Examining previous studies by other researchers was the primary research tool for this study. The organized approach of gathering data and assessing related work was vital in developing a fundamental basis for advancing knowledge on this concept while enhancing theory development and drawing more informed conclusion. Results: These four types, including the clan, adhocracy, hierarchical, and market cultures, contribute significantly in revealing four associations between the two variables, including (i) supportive culture and reduced stress, (ii) high pressure and increased stress, (iii)autonomous culture and variable stress levels, and (iv) open culture and low-stress levels. Conclusions: The literature affirms a multifaceted link between employee workplace stress and organizational culture type. The findings show that these cultures are crucial in influencing the level of stress among employees. All four types were hypothesized to have a significant relationship with job stress.

• Journal of radiological science and technology
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• v.34 no.2
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• pp.149-156
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• 2011

This study is to identify perceptions and response degrees of anxiety for each factor, targeting patients for CT test and analyze the relations between factors. It is to provide scientific fundamental data to reduce anxiety by improving awareness of patients about CT test by analyzing relations between variables. The subjects of this study were surveyed in self-writing type, targeting 263 patients for CT test in the department of radiology at three University hospitals from July to September, 2010. This survey was executed once by a structured self-administered survey type. The targeting patients for CT test of anxiety will investigate for affect. Anxiety by each CT test variables depending on CT test-related features showed independent variable is Expense Responsibility, Economic burden, Sufficient explain, Explain agent, Endoscope, Biopsy, Pre treatment, Previous experience, CT side effect experience, Side effect of contrast medium and dependent variable is physical, Hospital staff, Hospital environment, Socioeconomic These used statistics program SPSS (ver. 13.0). Summarizing the above results of this study, awareness of anxiety and response to it in each variable under CT test appeared significant differences in economic burdens, state anxiety, pre-treatment anxiety, exposure anxiety to radiation, and anxiety of side effect. Therefore, pre-treatment before test and pre-training programs on chemical poison of contrast medium and side effect seem to be able to release patients' anxiety level for CT test. Ways to meditate these anxiety variables and reduce degree of anxiety are needed to be researched more and updated. In addition, impact of patients' economic burdens on CT test anxiety is required to be recognized and solved in society level.

• Korean Journal of Applied Biomechanics
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• v.18 no.4
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• pp.99-107
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• 2008

The aim of this study was to provide fundamental data in training to improve athletes' competitiveness through the comparative analysis of kinematic variables according to the types of stance. For this study, the subjects selected 4 Junior Weight lifters. Subjects performed two type(8-type and 11-type) Dead-lift and their performance was sampled at 60frame/sec. using four high-speed digital video cameras. After digitizing images from four cameras, the two-dimensional coordinates were used to produce three-dimensional coordinates of the 15 body segments(20 joint makers and 2 bar makers). And the results were as follows. 1. As for the time required for stances, 8-type motion was faster than 11-type motion. 2. As for the body-center shift in stances, 8-type motion was bigger than 11-type motion in back and forth motion shift, and 11-type motion was bigger than 8-type motion in right and left, up and down motion shift. 3. As for the speed of a body-center and a babel, 8-type motion was faster than 11-type motion. 4. As for the motion-trace of a babel in stances, 8-type motion was bigger than 11-type in back and forth, right and left motion and 11-type motion was bigger than 8-type in up and down motion. 5. As for the body-angles in stances, 8-type motion was bigger than 11-type in the stance angle, and 11-type motion is bigger than 8-type in the angles of a coxa, a knee and an ankle. As a result of the comparative analysis between 8-type and 11-type stance of Junior Weight lifters dead-lift, both were generally similar in variables, but 8-type motion was more stable than 11-type in aspects of time, speed, center shift, angle change.

• Journal of the Economic Geographical Society of Korea
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• v.15 no.2
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• pp.332-342
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• 2012

The current research aims at classifying the bus stops as transfer center in order to establish the rational bus transfer systems. Existing research typically identifies characteristics of demands for bus stops and land use surrounding the bus stops and classifies and profiles the bus stops. A common problem with this type of research is that the results with cross-sectional characteristics of land use and bus stop usage do not capture the details of trip chain, the fundamental characteristics of the trips with transfer. This paper therefore examines bus stop classifications with such variables as transport mode chains, intermediate stop chains and timing chains. The analysis on the data collected on Monday 20 April 2009 for passengers of Gyeong-gi bus results in a clear classification among bus stops in terms of such trip chain variables. The research would provide useful information for the decision support of transfer stops location choice and infrastructure design.

• Journal of the Korean Home Economics Association
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• v.30 no.1
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• pp.179-198
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• 1992

The purspoe of this study is to identify the socialization level of household work of the employed and unemployed housewives and it's related variables in order to provide some fundamental information for the rational and effective performation of the household task. For the purpose of this study, 700 questionnaire were distributed to the employed and unemployed wives who lived in Seoul. The data were analyed by the Frequency distribution, Percentile, t-test, F-test, Duncan's Multiple Range Test, and Multiple Regression Analysis. The main results were as follows : (1) Socialization level of household work of the employed wives was a little below medium point. When the household work was devided into three subdomains, in the domain of food and shelter, the socialization level was far below medium point. In the domain of clothes, the socialization level was a little higher than medium point. Socialization level of household work of the unemployed wives far below average. When the household work was devided into three sudbomains, in the domain of food, clothes and shelter, the socialization level was far below average, too. Socialization level of household work was significantly different according to the employment. (2) Among the background veriables, family income, household work helper, and frequency of leisure activities have a significant influence on the socialization level of the employed wives. Duration of marriage, housewife's education level and house income have a important effect on the socialization level of the unemployed wives background. (3) Among the background variabels of household work, performing competence of household work is powerful effect on the socialization level of the employed wives. And as for the unemployed wives, performing competence of household task and recognition of the velue of household work are significant variables. (4) The psychological variable such as sex-role attitude gave no noticeable influence on the socialization level of employed and unemployed wives. (5) In conclusion, classifing the variances influencing on the socialization level of household work in a measure of respcetive effect, it appears to be performing competence of household task, frequency of leisure activities, house income, sex-role attitued and educational level in the order of their influences for the employed wives. And as for the unemployed wives, it seems to be house income, educational level, performing competence of household work and frequency of leisure activities. To the two sides, the rate of explanation is shown at 35%.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.5
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• pp.557-565
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• 2021

Path-following control is considered as one of the most fundamental skills to realize autonomous navigation of marine vessels in the ocean. This study addresses with the path-following control for a ship in which there are environmental disturbances in the directions of the surge, sway, and yaw motions. The guiding principle and back-stepping method was utilized to solve the ship's tracking problem on the reference path generated by a virtual ship. For path-following control, error dynamics is one of the most important skills, and it extends to the research fields of automatic collision avoidance and automatic berthing control. The algorithms for the guiding principles and error variables have been verified by numerical simulation. As a result, most error variables converged to zero values with the controller except for the yaw angle error. One of the most interesting results is that the tracking errors of path-following control between two ships are smaller than the existing safe passing distances considering interaction forces from near passing ships. Moreover, a trade-off between tracking performance and the ship's safety should be considered for determining the proper control parameters to prevent the destructive failure of actuators such as propellers, fins, and rudders during the path-following of marine vessels.

• (The) Korean Journal of Educational Psychology
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• v.31 no.1
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• pp.35-58
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• 2017

The achievement emotion experienced by students in their academic settings is directly related with achievement activities or results. As the focuses of researches in the educational psychology have been extended to students' motives and emotion, the achievement emotion is also actively studied in Korea. The purpose of this study is to analyze researches on the achievement emotion according to social/cultural backgrounds by dividing them into domestic and foreign ones and understand flow and trend of the researches by structuring them. On the basis of the findings, it also aims to provide fundamental data necessary to examine the achievement emotion matched for academic settings in Korea. The objects of this study include a total of 105 domestic (n=47) and foreign (n=58) journal articles. The criteria of analysis are divided into period, contents and method of the study: the study was conducted without control of period; the contents include variables and achievement situations; and the method includes design and type of study, analysis methods, measurement tools and objects. The descriptive statistics of the materials were estimated by using the SPSS, and were analyzed by dividing them into domestic and foreign ones. The findings show that the researches on achievement emotion can be divided into examinations of the development of achievement emotion scale and those of the relationship between related variables. Thus, the conclusion suggests comprehensive discussions by arranging the trends of researches on the development of achievement emotion scale and the relationship between related variables.