• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.6
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• pp.853-861
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• 2018

This paper proposes the application of harmonic constraints to address the problems caused by abnormal voltage increases when electric railway vehicles are running. The AC line that supplies the train with power during operation is used to provide electricity of 25kV/60 Hz, but gradually the size and frequency of harmonics involved in the line are varied with the technological evolution of the railroad vehicle electrical equipment. An increase in heat losses due to the failure of the instrument transformer (PT), the main circuit device, which is a serious problem with the recent train safety operation, or to the main displacement voltage. When high frequency components are introduced through low frequency Transformers of the main circuit device, the high intensity of the components is caused by the high intensity of the core and the current flow of the parasitic core is increased, thus generating heat. To solve this problem, the recent adjustment of the sequence has applied artificial NOTCH OFF of the power converter. However, the method of receiving and controlling the OFF signal operates by interaction between the ground and the vehicle's devices, thus it is invalid in the event of failure, and an actual accident is occurring. Therefore, the harmonic currents were required to prevent possible flow of harmonics, and conducted a study to prevent accidental occurrence of train accidents and to verify feasibility of the device through the simulations of the train's experimental analysis and the simulations of the train for safe operation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2C
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• pp.85-93
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• 2010

The shear stiffness has become an important design parameter to understand the soil behavior. In particular, the elastic moduli and void ratio has been considered as important parameters for the design of the geotechnical structures. The objective of this paper is the development of the penetration type Field Velocity and Resistivity Probe (FVRP) which is able to assess the elastic moduli and void ratio based on the elastic wave velocities and electrical resistivity. The elastic waves including the compressional and shear wave are measured by piezo disk elements and bender elements. And the electrical resistivity is measured by the resistivity probe, which is manufactured and installed at the tip of the FVRP. The penetration tests are carried out in calibration chamber and field. In the laboratory calibration chamber test, after the sand-clay slurry mixtures are prepared and consolidated. The FVRP is progressively penetrated and the data are measured at each 1 cm. The field experiment is also carried out in the southern part of Korea Peninsular. Data gathering is performed in the depth of 6~20 m at each 10 cm. The elastic moduli and void ratio are estimated based on the analytical and empirical solutions by using the elastic wave velocities and electrical resistivity measured in the chamber and field. The void ratios based on the elastic wave velocities and the electrical resistivity are similar to the volume based void ratio. This study suggests that the FVRP, which evaluates the elastic wave velocities and the electrical resistivity, may be a useful instrument for assessing the elastic moduli and void ratio in soft soils.

• Journal of Korea Entertainment Industry Association
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• v.13 no.8
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• pp.531-539
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• 2019

This study was intended to investigate the effects of parenting attitude of mothers of multicultural family and sensory processing skills of children on school readiness of preschool children. This study conducted Maternal Behavior Instrument(MBRI), Short Sensory Profile(SSP), and School readiness test on children of multicultural family and their mothers who are residing in Gwangju and Jeonnam, and results are as follows. According to the result of parenting attitude of mothers of multicultural family showed that total score 165.72±24.19. According to the result of investigating a correlation between parenting attitude of mothers of multicultural family and sensory processing skills of children on school readiness, only parenting attitude of mothers of multicultural family showed positive relationship with school readiness of children(p<.05). According to the result of investigating the effects of parenting attitude of mothers of multicultural family and sensory processing skills of children on school readiness, it was identified that parenting attitude of mothers of multicultural family makes significant effect on school readiness of children. To sum up, it is considered that parents education required for developing positive parenting attitude of mothers of multicultural family and mediations related to school readiness for school life adaptation of children of multicultural family are necessary for children of multicultural family to get adjusted to school life easily after they enter school.

• 한국노년학
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• v.30 no.4
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• pp.1095-1106
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• 2010

The purpose of this study was to develop a Abdominal Obesity Elderly(AOE) Health Status Scale to assess self rated health level. The subjects of this study were total 255(pretest 56, test 199) elderly over 65year. The data were collected between June to August, 2009. The method of this study as follow: items generation, test of validity and reliability, 5 panels of experts reviewed the preliminary questionnaire and then data were collected from elderly. Factor analysis, Cronbach's alpha, mean, standard deviation were analyzed the data by SPSS-Win 12.0 program. Results of factor analysis, 5 factors with a total of 16 items extracted that were Social level(Social participation 6 items, Physical Activity 2 items), Physical level(Disease Perception 4 items, Physical Index 2 items), Psychological level(Emotional Support 2 items). The reliability of the AOE health status scale was .868(Conbach's α). In the factor analysis Conbach's α correlations for the 5 factors ranged from .806 to .577. Therefore, Content validity, construct validity, reliability of the AOE health status scale were established. The AOE health status scale is a reliable and valid instrument which abdominal obesity elderly health status can be assessed.

• Journal of the Korean Society of Radiology
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• v.18 no.2
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• pp.127-133
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• 2024

The elbow joint is made up of three different bones. X-rays or other radiological exams are commonly used to diagnose elbow injuries or disorders caused by physical activity and external forces. Previous research on the elbow joint reported a new examination method that meets the imaging evaluation criteria in the tilt position by Z-axis elevation of the forearm. Therefore, this study aims to design an optimized instrument and develop an aid applicable to other upper extremity exams. After completing the 2D drawing and 3D modeling design, the final design divided into four parts was fabricated with a 3D printer using ABS plastic and assembled. The developed examination aid consists of a four-stage Z-axis elevation tilt angle function (0°, 5°, 10°, and 15°) and can rotate and fixate 360° in 1-degree increments. It was designed to withstand a maximum equivalent stress of 56.107 Pa and a displacement of 1.6548e-5 mm through structural analysis to address loading issues caused by cumulative frequency of use and physical utilization. In addition to X-ray exams of the elbow joint, the developed aid can be used for shoulder function tests by rotating the humerus and also be applied to MRI and CT exams as it is made of non-metallic materials. It will contribute to the accuracy and efficiency of medical imaging diagnosis through clinical applications of various devices and medical imaging exams in the future.

• Journal of The Korean Association For Science Education
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• v.26 no.6
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• pp.675-690
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• 2006

This study investigated students' views in relation to a career in science as a first step towards developing science career education programs and materials. The instrument was developed through preliminary surveys. The questionnaire was sent to, administered and returned by 3608 students including 1036 primary, 1137 middle, and 1435 high school students, who were selected through stratified cluster sampling from all over the country. The results were analyzed using statistical package program. The students' image view of science, preference for science and science learning, perception of science achievement, career hope for oneself, degree of hope in getting science-related job, perception about science-related career, important factors of science career choice, and their hope for science/non-science career and the reason for their choice in the past and present were investigated. The results show that "science as an experimentation activity" was the most frequent image view of science. The preference for science and science learning was more positive than the perception of science achievement. The percentage of total students who want to have science career was 21%, and this percentage of middle school students was especially low. The most frequent answers for advantages of science career were 'useful for national development', 'possible to get new knowledge', and those for disadvantages were 'dangerous', and 'too much to study'. The most frequent reason for students' choice of a science career was 'interest in science and science learning'. Judging from these results, the basic direction for science career education should be in raising the students' preference for and interest in science learning. The positive awareness for a career in science and vision for a science job in the future should be given through a science career education and science career education proper to the students' developmental stage and characteristics is more important.

• Journal of The Korean Association For Science Education
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• v.27 no.3
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• pp.272-284
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• 2007

The purpose of this study was to describe the scales of attitudes toward science and the validation of instruments for students and their parents. These instruments include three scales: cognition about value of science, affection toward science & science learning, and conative participation in scientific activities. A sample of middle school students (N=198) and their parents (N=153) was selected. Data analysis indicated that the instruments developed in this study had proper validity and reliability measures (${\alpha}=0.93$ for student questionnaire, ${\alpha}=0.88$ for parent questionnaire). The results reveal that both students and parents were well aware of the academic/vocational and social value of science, but they had low awareness of the individual value. In spite of that, students have positive feelings regarding enjoyment toward science and science learning, their self-concept and self-efficacy were low. And parents' responses were observed to support their kids in general field but not in science. Especially, female students had low participation in scientific activities and also their parents had low support for scientific activities (p<.0.1). Finally, there were positive correlations between students' attitudes toward science and their parents' affection toward science & science learning and conative participation in science activities.

• The Journal of Korean Medicine
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• v.45 no.1
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• pp.17-43
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• 2024

Objectives: Underpinned by the context of a Korean traditional medicine cohort study on healthy aging, this research primarily aims to guide the selection of Clinical Outcome Assessments (COAs) for elderly healthy aging patient registry research, offering insights into the selection process; and secondly, to streamline the resource-intensive process of obtaining permissions for validated COAs, benefiting future traditional Korean medicine clinical researchers. Methods : In this study, we identified outcomes through a review of previous studies, followed by a process involving expert consultations to select the final outcomes. Subsequently, for the selected outcomes that were Clinical Outcome Assessments (COAs) developed tools, we searched in commercial databases to confirm the availability of Korean versions and the necessity of obtaining permissions. Finally, we obtained permissions for their utilization and, when needed, acquired the original instrument questionnaire through payment. Results: Through a literature review of existing observational studies, a total of 57 outcomes were selected, with 19 of them identified as COA instruments. Upon verifying usage permissions for these 19 instruments, it was found that 17 required author-specific permissions, and among these, 2 needed a purchase as they were commercially available. Conclusion: This study provides a detailed overview of outcome selection and permission acquisition for elderly patient registry research. It underscores the importance of Clinical Outcome Assessment (COA) tools and the rigorous approval process, aiming to enhance research reliability. Continuous verification of COA information is essential, and future research should explore Core Outcome Set (COS) development through consensus-building approaches like Delphi studies.

• Journal of the Korea Society of Computer and Information
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• v.29 no.5
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• pp.111-121
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• 2024

With strength training comes the risk of injury and the benefits of exercise. Lack of knowledge and experience or repetitions at excessive intensity can lead to injury. Adequate feedback on an exercise's progress can increase the exercise's effectiveness and reduce injuries by providing scientific data and psychological motivation. This study aimed to validate EMG equipment and examine the effects of 8 weeks of biofeedback training with wireless electromyography. A correlation analysis between the Noraxon device and Fitsig^®(EMG Prototype), a well-known instrument in the field of research, showed a moderate correlation. Statistically significant differences in humeral circumference, humeral muscle mass, and biceps and triceps strength were found between the left and right sides of the body over time, with no differences in the type of exercise. Feedback training with real-time EMG was found to be favorable for hypertrophic growth and strength improvement. Future studies should be conducted to investigate its application in sports activities further.

• Journal of Nutrition and Health
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• v.57 no.3
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• pp.307-319
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• 2024

Purpose: This study compared the differences in health and dietary characteristics between middle-aged men and women according to their health-related quality of life. Methods: This study used the data from the 2019 and 2021 Korea National Health and Nutrition Examination Survey (KNHANES). The participants were men (n = 1,571) and women (n = 2,179) aged 40-59. A health-related Quality of Life Instrument with eight items (HINT-8) was used to measure the health-related quality of life. The participants were divided into four groups based on their HINT-8 total scores (high, mid-high, mid-low, and low). The general and health characteristics, mental health, and dietary behaviors were compared according to the quality of life. Results: Men with a lower quality of life had lower incomes, were more likely to be single, smoked and drank more, and perceived themselves as slim or obese. Women with a lower quality of life had a higher proportion of older age, obesity, lower education and income, hypercholesterolemia, and hypertriglyceridemia. Both men and women with a lower quality of life had higher proportions of subjectively perceiving poor health, weight gain over the past year, and considering themselves as obese. Both men and women with a lower quality of life had lower consumption frequencies of vegetables/mushrooms/seaweed and fruits. Conclusion: Both men and women with lower health-related quality of life had lower incomes, higher rates of perceiving their health as poor, and consumed vegetables/ mushrooms/seaweed and fruits less frequently, but they showed different characteristics in other aspects. Therefore, policy development tailored to men and women is necessary.