• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.296-301
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• 2023

Solid oxide fuel cell has received more attention recently due to the fuel flexibility via internal reforming. Commonly used Ni/YSZ anode, however, can be easily deactivated by carbon coking in hydrocarbon fuels. The carbon deposition problem can minimize by developing alternative perovskite anode. This study is focused on improving conductivity and catalytic activity of the perovskite anode by introducing rGO (reduced graphene oxide). Sr_0.92Y_0.08TiO₃(SYT) anode with perovskite structure was synthesized with 1wt% of rGO. The presence of rGO during anode fabricating process and cell operation is confirmed through XPS and Raman analysis. The maximum power density of rGO/SYT anode improved to 3 times in H₂ and 6 times in CH₄ comparing to that of SYT anode due to the high electrical conductivity and good catalytic activity for CH₄.

• KIPS Transactions on Computer and Communication Systems
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• v.12 no.3
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• pp.119-126
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• 2023

Sarcopenia is not well known enough to be classified as a disease in 2021 in Korea, but it is recognized as a social problem in developed countries that have entered an aging society. The diagnosis of sarcopenia follows the international standard guidelines presented by the European Working Group for Sarcopenia in Older People (EWGSOP) and the d Asian Working Group for Sarcopenia (AWGS). Recently, it is recommended to evaluate muscle function by using physical performance evaluation, walking speed measurement, and standing test in addition to absolute muscle mass as a diagnostic method. As a representative method for measuring muscle mass, the body composition analysis method using DEXA has been formally implemented in clinical practice. In addition, various studies for measuring muscle mass using abdominal images of MRI or CT are being actively conducted. In this paper, we develop an AI image segmentation model based on abdominal images of CT with a relatively short imaging time for the diagnosis of sarcopenia and describe the multicenter validation. We developed an artificial intelligence model using U-Net that can automatically segment muscle, subcutaneous fat, and visceral fat by selecting the L3 region from the CT image. Also, to evaluate the performance of the model, internal verification was performed by calculating the intersection over union (IOU) of the partitioned area, and the results of external verification using data from other hospitals are shown. Based on the verification results, we tried to review and supplement the problems and solutions.

• Journal of Korean Clinical Nursing Research
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• v.16 no.2
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• pp.95-105
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• 2010

Purpose: The purpose of this study was to identify the research trend of 341 studies published in Journal of Korean Clinical Nursing Research from 1995 to 2008. Methods: This study was conducted from May to November, 2009. The tool for analysis developed through literature reviews and discussions of researchers consisted of 7 categories such as characteristics of researchers, research designs, subjects, data collection methods, ethical consideration, nursing interventions, and dependent variables. Data were analyzed by frequency and percentage. Results: The mean number of author per study was 4.7, and clinical nurses were the most frequent as the first author (79.7%) and as a corresponding author (67.1%). Quantitative study was 97.6% and nonexperimental study was 51.7%. The most frequently used research designs were quasi-experimental study (73.9%) among experimental studies and survey study (79.1%) among nonexperimental studies. Patients were the most frequent subjects for studies (55.8%). 46.1% of studies gathered data with questionnaire, 57.7% of studies had consent from patients, and 44.3% of studies used nursing skills for nursing interventions, and 60.0% of studies used clinical end points for dependent variables. Conclusion: The research trend of clinical nursing studies shows that clinical nurses mostly perform quasi-experimental researches to solve patients' problem and frequently use nursing skills for nursing intervention and explore the effect of nursing interventions on clinical end points.

• Journal of Korean Elementary Science Education
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• v.42 no.1
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• pp.17-33
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• 2023

This study examined inservice elementary teachers' thoughts on the development of educational apps by preservice elementary teachers and implications for TPACK education for preservice elementary teachers. A case study was conducted in which preservice elementary teachers developed a science education app, and the three teachers were surveyed for their thoughts regarding this. The results regarding the characteristics of the developed app by preservice teachers were as follows. First, "inquiry" had the highest value among educational goals intended by the preservice teachers. In addition, the scores for tool-type apps and apps in which interaction between learners and instructors occurs were relatively high. Second, most of the preservice teachers developed apps to meet curriculum goals, but their apps showed low-level characteristics in terms of the constructive and cooperative dimensions. The results of the analysis of the thinking of elementary school teachers regarding the education development apps are as follows. First, elementary school teachers assigned the lowest scores to the effectiveness of the apps, and to this problem, the achievement standard with respect to the curriculum and the evaluation and modification activities fir the apps were proposed. Second, the teachers indicated that it would be appropriate to provide the experience of making apps to directly improve the TPACK of preservice teachers. Third, the respondents thought that preservice teachers should develop block coding literacy to create apps using App Inventor. Fourth, the teachers considered it necessary to emphasize simulated instructions, as well as the experience of collecting and handling data through apps to improve preservice teachers' TPACK app development for educational use.

• Journal of the Korean Geotechnical Society
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• v.24 no.7
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• pp.5-16
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• 2008

Most of roadway tunnels have been constructed in the form of parallel twin tunnel in Korea. If parallel twin tunnel does not have a sufficient separation distance between tunnels, the problem of tunnel stability can occur. Generally, it is reported that tunnels are not influenced by each other when a center distance between tunnels is two times longer than tunnel diameter under the complete elastic ground and five times under the soft ground. In this study, the scaled model tests of closely-spaced parallel twin tunnel using homogeneous material are performed and induced displacements are measured around the tunnel openings during excavation. The influence of separation distance between tunnels on the behavior of closely-spaced tunnel is investigated. The experimental results are expressed by the induced displacement vector and progress of crack during construction and at failure. The results show that based on the analysis of induced displacement at the crown during construction, the additional displacement of the preceding tunnel induced by the excavation of following tunnel decreases as the separation distance between twin tunnel increases until the center to center distance is two times of tunnel diameter. Beyond this point, however, the additional displacement has become stabilized.

• Korean Educational Research Journal
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• v.43 no.1
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• pp.59-87
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• 2022

'Thinking and Expression' develops comprehensive problem-solving ability to solve various problems in life and society by cultivating thinking skills such as creative, logical, reflective thinking, and connected thinking and communication ability to communicate one's thoughts through writing and speaking. This is a college basic liberal arts course established to improve students. The purpose of this study is to introduce the case of rewriting of literature reading and healing performed as an extension of storytelling learning in 'Thinking and Expression' class. In class, we read Michel Tournier's short story "Let Joy Remain in Me" and shared our feelings about the final scene of the work. Then, we each presented a question that came to mind as we read the work, and we shared our thoughts with the members of the group. Next, the students created the content that will follow the last scene of the work with the direction of healing. Through this, we tried to read the work carefully and deeply appreciate its contents, and we had time to feel the creative experience of the reader re-creating the meaning of the work and the effect of healing rewriting. Then, we turned the direction of reflection to the realm of the reader's own life and expressed their desired future self in writing, imagining that it had already been realized. Through this, we tried to discover the meaning of practical rewriting towards self-actualization.

• The Journal of the Korea Contents Association
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• v.22 no.5
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• pp.600-610
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• 2022

While Korean piano pedagogy has seen a remarkable growth, the relatively weak attention to intermediate level has emerged as a pending problem. The limited literature review, specifically the lack of playing Korean original works, has been considered as a serious issue. To emphasize the usefulness of Kim Kukjin's "Pieces of Korean Melody for Piano" as an intermediate work, this study presents practical teaching guidelines by classifying of difficulty in his 25 pieces and providing step by step learning goals and teaching plan. The difficulty stage was based on Jane Magret's 10-step classification table for comparison with other intermediate piano literature, and this study more specifically classified Kim's pieces according to Korean melody, rhythm, and texture. As a result of the difficulty classification, it was found that the pieces from stages 4 to 10 was organized to systematically and comprehensively learn step by step from the most basic progression to Korean 'Jangdan' rhythm patterns, various articulations and decorations that express 'Sigimsae' of Korean Traditional Music, and heterophony texture. In addition, this study proposed the order of pieces for the effective teaching according to the characteristics and difficulty of the pieces. This study suggests that the findings lead to the expansion of Korean intermediate literature study and the revitalization of Korean original works teaching method.

• Journal of The Korean Association For Science Education
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• v.43 no.2
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• pp.87-98
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• 2023

In this study, we investigated the change in science core competency perception of high school students and the reason for change when science inquiry classes were conducted using eight 'skills' of the 2015 revised science curriculum. Fifteen first-year high school students in Jeollanam-do participated in the science inquiry class of this study, and the class was conducted for 20 hours (5 hours a day for four days). The inquiry activities used in the class consisted of four activity stages (research problems, research methods, research results, and conclusions) and each stage was constructed to include at least one 'skill (Problem Recognition, Model Development and Use, Inquiry Design and Performance, Data Collection, Analysis and Interpretation, Mathematical Thinking and Computer Application, Conclusion and Evaluation, Evidence-based Discussion and Demonstration, and Communication)'. As a result of the study, students' perception of the five science core competencies increased statistically significantly at the significance level of 0.01 through inquiry classes and more than 93% of students recognized that their science core competencies improved through the classes. However, since the class of this study was conducted for a small number of students, it is difficult to generalize the effect of the class, and so it is necessary to conduct a quantitative study for many students.

• Korean Journal of Culture and Social Issue
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• v.29 no.2
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• pp.223-252
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• 2023

The aim of this study is to examine the longitudinal mediation effect of coping strategies(emotion-focused, problem-focused, and maladaptive) on the relationship between perceived stress during the COVID-19 andemic and psychological distress(negative affect, depression, anxiety, and anger). ). Also, This study sought to find generational differences between coping strategies used during the COVID-19 pandemic. The participants were 941 adult aged between twenties and seventies. The final participants were recruited on two separated longitudinal time points, Time 1 and Time 2. The result were as follows: Only Maladaptive coping strategy(Time 2) had a mediating effect on the relationship between COVID-19 stress(Time 1) and psychological distress(Time 2). . The result of the generation-based multi-group analysis did not yield significant differences in the use of coping strategies. This study is meaningful that it longitudinally examined the psychological distress of adults during the COVID-19 pandemic. Implications, limitations and directions for future research are presented.

• Nutrition Research and Practice
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• v.16 no.sup1
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• pp.113-125
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• 2022

In the current years, it has now become necessary to establish standards for micronutrient intake based on scientific evidence. This review discusses issues related to the development of the 2020 Dietary Reference Intakes for Koreans (KDRI) for magnesium (Mg), zinc (Zn), and copper (Cu), and future research directions. Following issues were encountered when establishing the KDRI for these minerals. First, characteristics of Korean subjects need to be applied to estimate nutrient requirements. When calculating the estimated average requirement (EAR), the KDRI used the results of balance studies for Mg absorption and factorial analysis for Zn, which is defined as the minimum amount to offset endogenous losses for Zn and Mg. For Cu, a combination of indicators, such as depletion/repletion studies, were applied, wherein all reference values were based on data obtained from other countries. Second, there was a limitation in that it was difficult to determine whether reference values of Mg, Zn, and Cu intakes in the 2020 KDRI were achievable. This might be due to the lack of representative previous studies on intakes of these nutrients, and an insufficient database for Mg, Zn, and Cu contents in foods. This lack of database for mineral content in food poses a problem when evaluating the appropriateness of intake. Third, data was insufficient to assess the adequacy of Mg, Zn, and Cu intakes from supplements when calculating reference values, considering the rise in both demand and intake of mineral supplements. Mg is more likely to be consumed as a multi-nutrient supplement in combination with other minerals than as a single supplement. Moreover, Zn-Cu interactions in the body need to be considered when determining the reference intake values of Zn and Cu. It is recommended to discuss these issues present in the 2020 KDRI development for Mg, Zn, and Cu intakes in a systematic way, and to find relevant solutions.