• Geomechanics and Engineering
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• v.35 no.5
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• pp.525-538
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• 2023

The development of a city is closely linked to the construction and operation of its subway system. However, constructing a new subway tunnel under an existing station is an extremely complex task, and the deformation characteristics and mechanical behavior of the new subway tunnel during the excavation process can greatly impact the normal operation of the existing station. Although the previous studies about the case of underpass engineering have been carried out, there is limited research on the condition of a newly-built subway tunnel that closely undercrossing an existing station with zero distance between them. Therefore, this study analyzes the deformation law and mechanical behavior characteristics of the preliminary lining of the underpass tunnel during the excavation process based on the real engineering case of Chengdu Metro Line 8. This study also makes an in-depth comparison of the influence of different excavation methods on this issue. Finally, the accuracy of numerical simulation is verified by comparing it with on-site result. The results indicate that the maximum bending moment mainly occurs at the floor slab of the preliminary lining, while that of the ceiling is small. The stress state at the ceiling position is less affected by the construction process of the pilot tunnel. Compared to the all-in-one excavation method, although the process of partial excavation method is more complicated, the deformation of preliminary lining caused by it is basically less than the upper limit value of the standard, while that of the all-in-one excavation method is beyond standard requirements.

• International Journal of Stem Cells
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• v.16 no.2
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• pp.202-214
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• 2023

Background and Objectives: To investigate the role of exosomes from periodontal ligament cells (PDLCs) in bone marrow mesenchymal stem cell (BMSC) migration. Methods and Results: Human PDLCs were applied cyclic tension stretching. Exosomes were extracted from cultured PDLCs by ultracentrifugation, then characterized for their size, morphology and protein markers by NTA, TEM and western blotting. The process that PKH26-labeled exosomes taken up by BMSCs was assessed by confocal microscope. BMSC migration was examined by Transwell assay. Exosomes derived from PDLCs were identified. Cyclic tension stretch application on PDLCs can enhance the migration ability of BMSCs through exosomes. The exosomal miRNA expression profiles of unstretched and stretched PDLCs were tested by miRNA microarray. Four miRNAs (miR-4633-5p, miR-30c-5p, miR-371a-3p and let-7b-3p) were upregulated and six (miR-4689, miR-8485, miR-4655-3p, miR-4672, miR-3180-5p and miR-4476) were downregulated in the exosomes after stretching. Sixteen hub proteins were found in the miRNA-mRNA network. Gene Ontology and KEGG pathway analyses demonstrated that the target genes of differentially expressed exosomal miRNAs closely related to the PI3K pathway and vesicle transmission. Conclusions: The exosomes derived from cyclic tension-stretched PDLCs can promote the migration of BMSCs. Alternation of microRNA profiles provides a basis for further research on the regulatory function of the exosomal miRNAs of PDLCs during orthodontic tooth movement.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.3973-3982
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• 2023

As for two-phase flow in rectangular channels, the flow regimes especially like churn-turbulent and annular flow are significant for the physical problem like Countercurrent Flow Limitation (CCFL). In this study, the rectangular channels with cross-sections of 4 × 66 mm, 6 × 66 mm, 8 × 66 mm are adopted to investigate the flow regimes of air-water vertical upward two phase flow under adiabatic condition. The gas and liquid superficial velocities are 0 ≤ j_g ≤ 20m/s and 0.25 ≤ j_f ≤ 3m/s respectively which covering bubbly to annular flow. The flow regimes are identified by random forest algorithm and the flow regime maps are obtained. As the results, the transitional void fraction from slug to churn turbulent flow fluctuate from 0.47 to 0.58 which is significantly affected by the dimensional size of channel and flow rate. Besides, the void fraction at transitional points from churn-turbulent (slug) to annular flow are 0.66-0.67, which are independent with the gap size. Furthermore, a new criteria of slug to churn-turbulent flow is established in this study. In addition, by introducing the interfacial force model, the criteria of churn-turbulent (slug) flow to annular flow is verified.

• 한국정보교육학회:학술대회논문집
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• 2021.08a
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• pp.321-326
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• 2021

In this paper, the information education plan of the Ministry of Education and offices of education was analyzed in relation to the construction of the AI convergence education room. And based on this, an appropriate construction direction was suggested. For research, AI convergence education room construction plan, budget amount per school and etc were analyzed in the information education plan of the Ministry of Education, KERIS, KOFAC, and the plan of leading schools for AI education. Although the Ministry of Education is making various efforts to promote SW education and artificial intelligence convergence education, it is found that the number is far insufficient compared to the number of elementary, middle and high schools. Efforts to expand the information education room at the government level are continuously required, and in order to utilize the developed artificial intelligence convergence education room, it is necessary to provide abundant teaching and learning examples for the construction space model. In addition, school-level planning and execution must be followed so that the constructed space can be used appropriately, and management and maintenance plans for equipment are required.

• Journal of Christian Education in Korea
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• v.65
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• pp.189-214
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• 2021

The aim of this research article is to investigate the life and educational ministry of friars, focusing on the Dominican friars, along with its influence on parish priests and laymen during late middle Ages. The friars' apostolic life and competent teaching ministry greatly contributed to the faith formation of the laity who desperately sought out sacred truth. In particular, the Dominican friars' teaching of orthodox theology and logical argument gave rise to the conversion of some heretics, including Cathars. In addition, their ministry helped parish priests maintain hold on the essence of the church and their apostolic vocation. Finally, the friars' educational ministry played a significant role in enabling the parish priests to take their responsibilities as confessors, teachers, preachers, and healers of souls.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.569-580
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• 2022

The Minister of Education has officially announced that the Ministry of Education will promote the integration of early childhood education and care. The core of integration is the integration of kindergartens and child care centers, and it is necessary to develop the specific model, so this study was conducted. After the discussion of integration, the discussion has focused on the "Young Children School", and there were differences of opinion on specific issues. Therefore, this study was conducted to propose the specific model for the "Young Children School" after kindergartens and child care centers were integrated with the Ministry of Education. The research question is to find out what the model of the 0-5-year-old young children school model centered on the Ministry of Education. In this study, assuming that integration of early childhood education and care was realized, a plan for integrating early childhood education institutions by type of establishment was proposed. As a conclusion of this study, first, a model of a 0-5-year-old young children school centered the Ministry of Education under the government responsibility is required. Second, a detailed school model that reflects the characteristics of each type of establishment should be developed. Finally, specific measures such as the reform of the teacher training system, the after-school course operation model, and the integration plan with the office of education and local governments should be presented during the young children school system.

• Journal of Distribution Science
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• v.21 no.4
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• pp.47-56
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• 2023

Purpose: the research aims to analyze the impact of the distribution of knowledge through online learning on the intellectual potential of PhD students and produce recommendations for policy to improve intellectual capacity. During the literature review, it was determined that a large number of studies examined the impact of online learning on the quality of education at different levels. Research design, data and methodology: the research methodology is based on subjective assessment and studying the students' opinions. The basis of the study was a comprehensive analysis of primary data obtained through a sociological survey of PhD students. 324 respondents from humanitarian, medical and natural faculties participated in the survey. Results: the study revealed that online learning helps increase students' intellectual potential. PhD students had a positive attitude towards the transition from traditional education to online learning. It should be noted that, according to the results, the most popular gadgets were laptops and smartphones, which were characterized by high mobility and ease of use. Based on the obtained results, recommendations were developed for the formation of online learning with a focus on increasing students' intellectual potential. Conclusions: based on the results of the assessment of educational and innovative potential, policy recommendations and further research in this area were proposed.

• The Korean Nurse
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• v.10 no.2 s.52
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• pp.48-52
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• 1971

• International Journal of Advanced Culture Technology
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• v.11 no.2
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• pp.44-48
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• 2023

To enhance safety in dangerous situations, it is essential to provide practice-oriented safety education. However, direct experiences can be limited, and thus, metaverse-based safety education is emerging as an alternative. In this study, we analyzed the first official metaverse safety education program of the Korea Ministry of Education, mainly focusing on its title, objectives, content, and results using the Revised PRISMA framework. The program concentrates on "life safety" for "fire safety," "disaster safety" for "earthquake safety," and "first aid" for "abrasions, burns, fractures, cardiopulmonary resuscitation, and the use of AED." We classified the objectives of the entire program and its three sub-programs, and identified the knowledge, main practice tasks, and their results. The aim of this study is to promote an understanding of the main cases of national-led metaverse safety education and infer the practical safety education contents emphasized to Korean school-age students.

• The Journal of Korean Society for School & Community Health Education
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• v.8 no.1
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• pp.1-11
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• 2007

Objectives: School must provide the proper sex education to students, thereby, the students for have right standards of sexuality and preventing from sexual crimes. This study conducted to identify the effectiveness and students' satisfaction level on Sex education program for middle school students prepared by the Ministry of Education and Human Resources. Methods: The sample size of the study was 644 students(458 female students and 186 male students) in middle school. A self reporting type of questionnaire survey was conducted from May 2 through May 27, 2005. Collected data were processed using SPSSwin 12.0; The data were analysed through t-test, stepwise multiple regression analysis. Results: Lectures and audiovisual materials were mostly used for sex education for students. Many students were satisfied with the program of physical and sexual organ development, pregnancy, contraceptive methods and sexual abuse. Many students wanted to study more on courtship, love, and marriage. The programs which the students did not understand well were sexually transmitted diseases, pregnancy and mass media and sex. Forty six percentage of the students reported that they were satisfied with the education program. Thirty three percentage of the students said that they were not satisfied with the program. The students who had earlier menstruation experience and the students whose academic achievement were higher were more satisfied with sex education program (P<.05). The students who were satisfied with the sex education CD prepared by the ministry of education were more satisfied with sex education program. (P<.001). When the CDs were appropriately used, the students were more satisfied with the education program (P<.05). The sound and pictures in the CD did not much affect the students. Audiovisual programs were more effective than lectures.