• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.36 no.1
• /
• pp.9-16
• /
• 2012

Recently, an optics-based concentrator for solar concentration has been a key issue in development of photovoltaic systems. In the present study, a new, simple, easily producible planar concentrator based on a light guide system is proposed. In this device, solar light is concentrated by microprism optical patterns guiding the light, mainly through total reflection and refraction. The main design variables of the concentrator are the geometric concentration ratio ($R_c$) and the ${\Theta}_1$ and ${\Theta}_2$ of the microprism pattern. Ray tracing was simulated using commercial software, SPEOS, and the optical efficiencies of the light guide solar concentrator were predicted in each case. The predicted maximum optical efficiencies are 65.60%, 54.78%, and 46.78%, respectively, for $R_c$ values of 4, 5, and 6. The variation of the optical efficiencies according to ${\Theta}_1$, ${\Theta}_2$, and the incline angle of the incident light were predicted.

• Journal of Gifted/Talented Education
• /
• v.22 no.2
• /
• pp.427-450
• /
• 2012

This study was intended to develop a self-report wisdom scale for the elementary gifted students. For this, related literature was reviewed in depth and open ended questionnaire about the wisdom qualities was conducted. Based on these, a self-report wisdom scale, which was comprised of 42 items in 4 factors such as the situation judgment and problem-solving ability, the communication ability and skills, the emotional stability, the insight and adaptation, was developed. For this preliminary scale, 215 elementary gifted students were surveyed. And for the confirmatory factor analysis, 256 elementary gifted students participated. The results of the study were as follows. The fit of measurement model was found to be ${\chi}^2$=1596.46 (df=813, p=.00), TLI .90, CFI .91, RMSEA .046, indicating most of fit indexes were acceptable. The reliability for each of 42-item by the sub-factors also appeared to be good, showing that internal consistency reliability by the configuration factors was 0.86, .87, .89, .87 each relatively. In addition, to verify the validity of the wisdom scale, the convergent and discriminate validities were obtained through the correlation analysis among the psychological characteristics which were considered to be related to the wisdom. Finally, practical implications of the study were discussed in depth.

• Journal of Gifted/Talented Education
• /
• v.19 no.1
• /
• pp.1-23
• /
• 2009

Science field trip is a comprehensive learning activity in which students can solve problems by themselves, whose importance is emphasized in learning for the gifted. But because not much study has been done yet on this, and convergent activities such as solving too many problems or requesting given answers have generally been done, it has been criticized for not being enough to develop the abilities of gifted Students. Therefore, this study attempted to analyze the activity process of the gifted through field trip to which open inquiry is adapted so that the demands of the gifted can be met, and the abilities of the gifted can be brought out. The study focused on 18 gifted elementary science students at Institute of Science Gifted Education, Cheongju National University of Education, and in the field trip process of the students, analyzed the types of establishment of inquiry problems and inquiry process, and the behavioral characteristics of gifted science students shown during field trip activity through field trip proceedings, transcript contents, poster materials, questionnaires, etc. As a result, more inquiry problems were established after than before inquiry, and the level of inquiry problems was also higher after inquiry. The solution process for inquiry problems of the gifted science students were done in the following order: planning, inquiring, follow-up inquiring and consolidating. But it proceeded to open inquiry process, the next stage being decided according to circumstances. Also, in the inquiry that the students did, diverse factors were revealed such as basic and integrative inquiries, and especially, the students were competent in analyzing the results after transforming and interpreting them. And the analysis of the interaction among the students showed many behavioral traits of talented science students.

• Journal of the Korea Convergence Society
• /
• v.11 no.9
• /
• pp.175-180
• /
• 2020

In this study, the freight vehicles were modelled and the flow analysis on the existence or non-existence of a cargo container and the wind deflector were carried out. Based on the driving speed of 100 km/hr, at all models A, B and C, the highest flow rate was shown between 58 m/s and 59 m/s at the top of the model shape. All models A, B and C showed the highest pressure of air resistance between 652Pa and 671Pa at the front of the model geometry. The maximum pressure of model A is considered to be the smallest, with the least flow resistance to speed compared to models B and C. Therefore, it can be seen that model A has an advantageous condition for air resistance in terms of fuel costs. Unlike model B which causes the rapid flow resistance at the cargo compartment, model C can be found to flow a little more smoothly on the streamlined wind deflector. So, the flow air at a streamlined shape is considered to be more advantageous in terms of air resistance than at angular shape. By applying the research analysis result on the air flow in driving according to a cargo container and the wind deflector, it is seen that this study is adequate at the practical efficient design and aesthetic convergence.

• Journal of the Korean association of regional geographers
• /
• v.22 no.4
• /
• pp.887-911
• /
• 2016

The empirical law that transverse dunes migrate inversely with their heights leads logically to the prediction that multiple dune ridges will converse to a single huge dune by merging. This contradicts the existence of the steady state dune fields on the Earth. The recent studies have emphasized dune collisions as a key mechanism to the stability of dunefield. The roles of wind shadow aspect ratio, however, have yet to be fully explored. This research aims to investigate the potential roles of wind shadow aspect ratio in the dynamical behaviors of transverse dune field. The simplified model is established for this, based upon allometric properties of transverse dunes, wind speedup on the stoss slope and sand trapping efficiency. The derived governing equations can be transformed to the zoning criteria and vector field for dune evolution. The dynamics analysis indicates that wind shadow aspect ratios do not produce convergent areas on the behavior space; rather, they just act as one of the factors that affect the trajectories of dune evolution. Though the model cannot represent the stability of dune field, but seem to produce a reasonable exponent for dune spacing-height relations.

• Journal of Digital Convergence
• /
• v.19 no.10
• /
• pp.319-327
• /
• 2021

The aim of this study is to identify the relationship between obesity and dieting to dental care in a convergent manner. This is a secondary analysis study using data from National Health and Nutrition Survey(2008 & 2018), and the subjects of the study are those with permanent treatment experience. The data in this study were t-test, ANOVA and regression analysis using SPSS /WIN 24.0. As a result of the study, The experience of permanent tooth caries according to gender was high in woman(M=.76, W=.83), and the experience of permanent tooth caries according to the educational level showed that the caries experience of high-educated level(College or higher=.92). In the difference according to the subjective body type recognition, it was confirmed that obesity was associated with the experience of permanent tooth caries. Among the weight control methods, fasting was the most influential on the permanent tooth caries experience. The experience of permanent tooth caries according to the weight change was found to have an effect on both weight loss and increase, In future studies, not only studies of sugar intake related to obesity, but also proper oral health education study that informs about the risk of dental caries in the diet that is progressing in line with the current trend should be continued.

• Journal of Internet Computing and Services
• /
• v.20 no.4
• /
• pp.81-90
• /
• 2019

Since 2015, the government has been striving to strengthen the software capabilities required for future talent through software-oriented university in Korea. In the university selected as a software-oriented university, basic software education is given to all departments such as humanities, social science, engineering, natural science, arts and the sports within the university in order to foster convergent human resources with different knowledge and software literacy. In this paper, we analyze the contents of basic software education for twenty universities selected as software-oriented universities. As a result of analysis, most of the basic software education which is carried out to the students of the non-majors students was aimed at improvement of problem solving ability centered on computational thinking for future society and improvement of convergence ability based on computer science. It uses block-based educational programming language and text-based advanced programming language to adjust the difficulty of programming contents and contents reflecting characteristics of each major. Problem-based learning, project-based learning, and discussion method were used as the teaching and learning methods for problem solving. In the future, this paper will help to establish the systematic direction for basic software education of non-majors students.

• Journal of Digital Convergence
• /
• v.16 no.12
• /
• pp.1-10
• /
• 2018

For local festivals to be successful, it is important to cooperate with various entities and effectively utilize festival-related resources. Recently, many efforts have been made to improve the operation and management performance of local festivals in Korea, but systematic management and IT support have been insufficient. In this study, the factors affecting the IT governance of local festivals were derived through a literature review and the relationship to the festival performance was analyzed empirically. A survey was conducted with local festival organizers and stake holders, and the research model was verified using the regression analysis with total 109 samples. According to the results of the analysis, it was confirmed that marketing, processes and service management have a significant effect on festival performance within IT governance. The effect of festival performance on resource management was not statistically significant. This study demonstrates that the systematic operation and management of local festivals using IT governance is necessary for local festivals. It will be more meaningful if further study discuss the IT utilization guidelines and success cases through the innovative use of IT for local festivals.

• The Journal of Korean Academy of Sensory Integration
• /
• v.17 no.1
• /
• pp.19-29
• /
• 2019

Objective : The aim of this study was to verify validity of the Activity Participation Assessment for school-age children. Methods : A questionnaire consisting of 30 items from the APA, 75 items from the PACS, and 55 items from the CAPE was administered to elementary school students. A total of 207 questionnaires were analyzed. Confirmatory factor analysis was performed to confirm the construct validity of the APA. Convergence validity and discriminant validity were verified with the average variance extracted (AVE) and the square of the correlation coefficient. The discriminant validity was the Pearson correlation coefficient of the APA, PACS, and CAPE. Results : The results of the analysis were as follows: 1) For construct validity, the goodness of fit of the modified hierarchical second-order factor model was found to be appropriate (p < .001), 2) For convergent validity, the AVE was higher than .50 for all latent variables, 3) For discriminant validity, the AVE of the latent variable was greater than the square of the correlation coefficient (0.239), 4) For concurrent validity, the correlation between the total sum of the APA and PACS scores showed a positive correlation in all domains, and the correlation coefficient ranged from .303 to .647 at a statistically significant level (p < .01), 5) The correlation coefficient between the total sum of the APA and CAPE scores was .490 for recreational activities, .329 for physical activities, .571 for social activities, .401 for skill-based activities, and .390 for self-improvement activities. All domains showed a positive correlation, and were statistically significant (p < .01). Conclusion : APA can be used as a valid assessment tool to measure the participation of school aged children.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.12
• /
• pp.218-226
• /
• 2018

The purpose of this study was to examine the validity and reliability of the Korean version of the nursing students' perception of instructor caring (NSPIC) scale developed by Wade and Kasper for nursing students. We collected data from 219 nursing students in the 3rd to 4th year at three nursing colleges from June 4 to June 20, 2018. Data were analyzed using SPSS 21.0 and AMOS 21.0. An exploratory factor analysis with varimax rotation was performed, resulting in five factors (respectful sharing, confidence through caring, control versus flexibility, supportive learning climate, appreciation of life's meanings) with a total of 27 items. Confirmatory factor analysis supported good convergent and discriminant validities. In addition, the concurrent validity test confirmed that the K-NSPIC scale was a validity tool as the correlation of the clinical learning environment (CLE) scale appeared as r=.64 (p<.001). The Cronbach's alpha coefficient of the K-NSPIC was .88, and Cronbach's alpha coefficient for each of the five factors was .91, .86, .80, .76, and .85; internal consistency was confirmed. It is significant that the K-NSPIC proved applicable as a useful tool for assessing instructor caring. It is also expected that it will assist in the design of programs to improve the caring ability of instructors.