• Education of Primary School Mathematics
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• v.26 no.3
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• pp.141-162
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• 2023

Recently, in school mathematics, classes using mathematical modeling are attracting attention to improve students' mathematical problem-solving skills. However, existing preceding studies have been conducted mainly on elementary, middle, and high school or in-service teachers, so it may be limited to apply the contents and results of the research as it is to pre-service teachers, who are future professors. Therefore, this study examined the school days' experiences of mathematical modeling for pre-service elementary school teachers. In addition, in order to provide a positive experience for mathematical modeling, mathematical modeling problem creation activities were conducted through group activities, and the results and their perceptions were examined. As a result of the study, elementary school preservice teachers had very little experience with mathematical modeling activities during their elementary, middle, and high school days. It was found that there is a deficiency in creating an appropriate mathematical modeling problem suitable for the level of elementary school students. In addition, it was found that they had a positive perception of mathematical modeling after participating in the study. Based on these results, implications for the training process for preservice teachers were suggested.

• Journal of Service Research and Studies
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• v.11 no.4
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• pp.43-55
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• 2021

This study analyzed the efficiency of medical services in OECD member countries by dividing it into operational efficiency and quality efficiency. For this purpose, data from 2017-2019 OECD Health Statistics were used. As the analysis method, super efficiency was measured by applying an output-oriented Variable Returns to Scale (VRS) model. As a result of the analysis, Switzerland, Korea, and Italy were included in the high group of operational efficiency, Canada, Greece, Denmark, etc. in the medium group, and Belgium, Germany, and Spain in the low group. Based on quality efficiency, Norway, Switzerland, and Spain are in the high group, and Greece, Denmark, Mexico, etc. are in the medium group, and the Netherlands, Germany, Belgium, etc. were included in the low group. As a result of comparative analysis of efficiency by OECD member countries as of 2018, it was found that Korea's operational efficiency was the most efficient and quality efficiency was inefficient. Korea (0.998) should improve life expectancy by 0.2 (0.2%) and subjective health perception by 44.2 (138.1%) by benchmarking Greece (0.422), Switzerland (0.207), and Spain (0.371) to improve quality efficiency. Unlike most previous studies that focused on operational efficiency, this study measured quality efficiency together and analyzed the efficiency of the medical service industry in each OECD member country. Through this, this study has implications in that it confirmed the international competitiveness of the domestic medical service industry and suggested ways to improve efficiency.

• Journal of Ocean Engineering and Technology
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• v.37 no.2
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• pp.58-67
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• 2023

While extensive research is being conducted to reduce greenhouse gases in industrial fields, the International Maritime Organization (IMO) has implemented regulations to actively reduce CO₂ emissions from ships, such as energy efficiency design index (EEDI), energy efficiency existing ship index (EEXI), energy efficiency operational indicator (EEOI), and carbon intensity indicator (CII). These regulations play an important role for the design and operation of ships. However, the calculation of the index and indicator might be complex depending on the types and size of the ship. Here, to calculate the EEDI of two target vessels, first, the ships were set as Deadweight (DWT) 50K container and 300K very large crude-oil carrier (VLCC) considering the type and size of those ships along with the engine types and power. Equations and parameters from the marine pollution treaty (MARPOL) Annex VI, IMO marine environment protection committee (MEPC) resolution were used to estimate the EEDI and their changes. Technical measures were subsequently applied to satisfy the IMO regulations, such as reducing speed, energy saving devices (ESD), and onboard CO₂ capture system. Process simulation model using Aspen Plus v10 was developed for the onboard CO₂ capture system. The obtained results suggested that the fuel change from Marine diesel oil (MDO) to liquefied natural gas (LNG) was the most effective way to reduce EEDI, considering the limited supply of the alternative clean fuels. Decreasing ship speed was the next effective option to meet the regulation until Phase 4. In case of container, the attained EEDI while converting fuel from Diesel oil (DO) to LNG was reduced by 27.35%. With speed reduction, the EEDI was improved by 21.76% of the EEDI based on DO. Pertaining to VLCC, 27.31% and 22.10% improvements were observed, which were comparable to those for the container. However, for both vessels, additional measure is required to meet Phase 5, demanding the reduction of 70%. Therefore, onboard CO₂ capture system was designed for both KCS (Korea Research Institute of Ships & Ocean Engineering (KRISO) container ship) and KVLCC2 (KRISO VLCC) to meet the Phase 5 standard in the process simulation. The absorber column was designed with a diameter of 1.2-3.5 m and height of 11.3 m. The stripper column was 0.6-1.5 m in diameter and 8.8-9.6 m in height. The obtained results suggested that a combination of ESD, speed reduction, and fuel change was effective for reducing the EEDI; and onboard CO₂ capture system may be required for Phase 5.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.57-65
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• 2023

This study examined the obstacles of important factors involved in the start-up decision process for prospective entrepreneurs and plans after graduation while attending hair and beauty colleges and analyzed them in a phenomenological way to establish countermeasures. The subjects of the study agreed to collect data from 10 prospective entrepreneur doctors and plans after graduation while attending hair and beauty college located in G, and were in-depth from December 15 to December 30, 2022. The collected data were analyzed using the Colaizzi method. The results of this study were extracted with 13 topics and two subject collections that represent the characteristics of the experience in the preliminary start-up process of the participants. Based on the results of this study, it is meaningful to examine the obstacles of the factors that are importantly involved in the start-up decision process and establish countermeasures accordingly. In conclusion, at a time when the market for start-ups is expanding and government support is increasing, the factors affecting the will of college students, who are potential professional managers in the future, and effective implications for enhancing the university's start-up infrastructure, start-up difficulties, and start-up motivation were obtained. Therefore, it is urgent to develop efficient performance counseling research or program counseling that can promote and support mental and environmental growth through career development required for the difficulties of the decision process of prospective entrepreneur hair college students and the situations they face. It is necessary to develop various measurement tools in consideration of the level of career development and development of a start-up decision-making process model that can fully grasp the status of start-ups of prospective start-ups.

• Journal of the Korean earth science society
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• v.44 no.1
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• pp.47-61
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• 2023

Rather than an abstract discourse, the purpose of this study is to outline the core concepts in the 2015 revised curriculum as a concrete teaching and learning method in the school context. We interviewed eight secondary science teachers and reported their perceptions and perspectives on core concepts using a backward design model based on the cyclical process of the platform, deliberation, and design for developing teaching and learning materials to understand core concepts. The participants perceived these core concepts differently, such as big ideas corresponding to the ultimate principle, minimum science concepts required for daily life, and primary and significant key concepts. In addition, this affects the association of teaching and learning. When core concepts are understood as transferable and expandable big ideas, there is a tendency to focus on the relationship between concepts and design project learning in a specific direction. However, if core concepts are identified as minimum science concepts at the level of science literacy, that can be recalled within the context of life, there is a tendency to emphasize on activities that make a meaningful difference to the lives of students with focus on case studies that are relevant to everyday life. Once core concepts are identified as key scientific content elements, such as basic or significant concepts, teachers recognize that it is essential to emphasize concept changes by correcting misconceptions, acquiring accurate scientific knowledge, and developing problem-solving items through paper-and-pencil evaluation. As the 2015 revised curriculum is finalized and the 2022 revised curriculum is scheduled for release, effective policy support is required to ensure that the curriculum is revised, which emphasizes the purpose of big ideas by naming core concepts as core ideas, to be stably implemented in schools.

• Journal of the Korea Society of Computer and Information
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• v.28 no.4
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• pp.133-142
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• 2023

National parks are one of the important types of protected area management systems established by IUCN and a management model for implementing effective conservation and sustainable use of natural and cultural heritage in countries around the world, and they assume important roles in conservation, scientific research, education, recreation and driving community development. In the context of big data, this study takes China's Liaohe National Park, a typical representative of global coastal wetlands, as a case study, and using Python technology to collect tourists' travelogues and reviews from major OTA websites in China as a source. The text spans from 2015 to 2022 and contains 2998 reviews with 166,588 words in total. The results show that wildlife resources, natural landscape, wetland ecology and the fishing and hunting culture of northern China are fully reflected in the perceptions of visitors to Liaohe National Park; visitors have strong positive feelings toward Liaohe National Park, but there is still much room for improvement in supporting services and facilities, public education and visitor experience and participation.

• Journal of the Korean Applied Science and Technology
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• v.39 no.2
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• pp.246-260
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• 2022

This study was conducted to analyze the creativity education contents of dance activities in physical education textbooks for the 3rd and 4th grades of elementary school. For this purpose, 16 types of textbooks and auxiliary data for physical education in the 3rd and 4th grades of elementary school were collected and analyzed using the creative education content analysis frame of the physical education textbook based on the 4P model. In order to secure the integrity of the research, expert consultation was operated. The results of this study are as follows. First, from the viewpoint of creative person, 'inquiry' was the most common in creative mind, and the rest of the elements appeared relatively evenly. As for the subject of activity, 'individual' and 'colleague (team)' showed similar frequencies. Second, from the viewpoint of the creative process, all activity areas appeared as 'learning', and most of the elements of the activity purpose appeared evenly, and the creative process was explored. Third, from the viewpoint of creative output, physical activity performance was the most common activity method, and two or three activity methods were used together. In the creativity factor, all factors appeared evenly, and sensitivity and sophistication were the most common with 4 factors. Fourth, from the viewpoint of the creative environment, most of the activity spaces were no restrictions, and the activity media consisted of many educational contents using the body. Through this study, it was requested that creativity education in dance activities should be expanded quantitatively and intensified in quality, and the necessity of spreading creativity education contents of dance activities to other areas was explored.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6A
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• pp.789-798
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• 2008

The stiffness method provides a framework to calculate the structural deformations directly from solving the equilibrium state. However, to use the displacement shape functions leads to approximate estimation of stiffness matrix and resisting forces, and accordingly results in a low accuracy. The conventional flexibility method uses the relation between sectional forces and nodal forces in which the equilibrium is always satisfied over all sections along the element. However, the determination of the element resisting forces is not so straightforward. In this study, a new fiber finite element mixed method has been developed for nonlinear anaysis of steel-concrete composite structures in the context of a standard finite element analysis program. The proposed method applies the Newton method based on the load control and uses the incremental secant stiffness method which is computationally efficient and stable. Also, the method is employed to analyze the steel-concrete composite structures, and the analysis results are compared with those obtained by ABAQUS. The comparison shows that the proposed method consistently well predicts the nonlinear behavior of the composite structures, and gives good efficiency.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3C
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• pp.187-196
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• 2008

An earthquake of magnitude 5.0 occurred at Ssang-gye-sa, a Buddhist temple in Jirisan, located near the southern border of the Korean peninsula on 4 July 1936. It resulted in severe damage of several buildings and structures in Ssang-gye-sa. Particularly, the top component of a five-story stone pagoda in the temple was tipped over and fell down during the earthquake. This earthquake damage case would be usefully applied to estimating the intensity of ground motion in the Korean peninsula, a moderate seismicity region, where strong motion has never been recorded with the exception of historic seismic events. In order to estimate the local site effects and the corresponding ground motion at Ssang-gye-sa site, intensive site investigations including borehole drilling and in-situ seismic tests such as crosshole and SASW tests were performed in the temple area. Based on the site characteristics, site-specific seismic response analyses using various input motions were conducted for a representative Ssang-gye-sa site by means of both one-dimensional equivalent-linear and nonlinear methods with six input rock outcrop acceleration levels ranging from 0.044g to 0.220g. The resultant site-specific seismic responses indicated the amplified ground motions in the short-period range near the site period of Ssang-gye-sa. Furthermore, the intensity on rock outcrop of the 1936 Jirisan earthquake was estimated by making a comparison between the site responses analysis results in this study and the full-scaled seismic test of pagoda model in the prior study.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1D
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• pp.157-167
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• 2006

During the first and second NGIS projects by the Korean government, The first one (1995~2000) was limited on constructing geographic information and the second (2001~2005) was focused on circulation and practical use of geoinformation from the result of the first project. In the latter half of 2nd NGIS project, However, the geographic information from the NGIS projects have not been renewed even though there were significant geographical changes. The accurate renewal of geoinformation is a matter of great importance to the next generation industry (e.g. LBS, Ubiquitous, Telematics). In this respect, it is time to update the geographic information in the latter half of the second NGIS project. Therefore, It is not only important to build an accurate geoinformation but also rapid and correct renewal of the geoinformation. NGII (National Geographic Information Institute) has been studying for improvement of digital map that was constructed by the result of the 1st NGIS project. Through the construction of clean digital map, NGII constructed Framework Data to three kinds of formats (NGI, NDA, NRL). Framework Data was contained to other database, and provided the reference system of location or contents for combining geoinformation. Framework Data is consist of Data Set, Data Model and UFID (Unique Feature Identifier). It will be achieved as national infrastructure data. This paper attempts to explore a method of the update to practical framework data with realtime geoinformation on feature's creation, modification and destruction managed by 'Feature management agency' using UFID's process. Furthermore, it suggests a method which can provide important data in order to plan the Framework update with the land change ratio.