• Journal of Science Education
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• v.47 no.3
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• pp.225-237
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• 2023

The purpose of this study is to explore the perceptions of elementary pre-service teachers regarding their interest in science. A survey was conducted among 187 elementary pre-service teachers enrolled at Non-Metropolitan Area A University of Education. Data collection was carried out concurrently with three elementary pre-service teachers who agreed to participate in online interviews. The survey responses provided by the elementary pre-service teachers were analyzed using a qualitative text analysis method. Interest in science was observed to decrease during middle school, followed by the upper grades of elementary school and then the lower grades. The reasons for the decline in interest in science were interpreted as stemming from negative experiences with science education within the context of individual circumstances in the school setting. Strategies to address the decline and enhance interest in science were discussed across individual, family, school, teacher, local community, and national levels, considering both short-term and long-term perspectives. These strategies encompassed various inquiry activities and experiences related to the field of science, engagement in science-related activities, student-centered instruction, teacher professional development, support for elementary students and teachers, and policy measures. The multifaceted approach and efforts aimed to open avenues for positive feedback regarding science on an individual level and foster experiences related to science were interpreted as part of an effort to counteract the decline in interest in science. Lastly, given the current situation of declining interest in science and the need to enhance students' interest, it was implicitly and explicitly discussed that pre-service teachers should focus on improving their expertise in curriculum instruction. This research, by exploring the conceptual characteristics of interest in science, perceptions of changes, and educational needs related to interest in science among elementary pre-service teachers, is expected to have academic significance as foundational research data for the current status of declining interest in science.

• Korean Journal of Remote Sensing
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• v.40 no.3
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• pp.295-305
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• 2024

This study aims to analyze the micro-sedimentary structures of the Hwangdo tidal flats using ultra-high resolution unmanned aerial vehicle (UAV) data. Tidal flats, located in the transitional area between land and sea, constantly change due to tidal activities and provide a unique environment important for understanding sedimentary processes and environmental conditions. Traditional field observation methods are limited in spatial and temporal coverage, and existing satellite imagery does not provide sufficient resolution to study micro-sedimentary structures. To overcome these limitations, high-resolution images of the Hwangdo tidal flats in Chungcheongnam-do were acquired using UAVs. This area has experienced significant changes in its sedimentary environment due to coastal development projects such as sea wall construction. From May 17 to 18, 2022, sediment samples were collected from 91 points during field surveys and 25 in-situ points were intensively analyzed. UAV data with a spatial resolution of approximately 0.9 mm allowed identifying and extracting parameters related to micro-sedimentary structures. For mud cracks, the length of the major axis of the polygons was extracted, and the wavelength and ripple symmetry index were extracted for ripple marks. The results of the study showed that in areas with mud content above 80%, mud cracks formed at an average major axis length of 37.3 cm. In regions with sand content above 60%, ripples with an average wavelength of 8 cm and a ripple symmetry index of 2.0 were formed. This study demonstrated that micro-sedimentary structures of tidal flats can be effectively analyzed using ultra-high resolution UAV data without field surveys. This highlights the potential of UAV technology as an important tool in environmental monitoring and coastal management and shows its usefulness in the study of sedimentary structures. In addition, the results of this study are expected to serve as baseline data for more accurate sedimentary facies classification.

• Journal of the Korean Applied Science and Technology
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• v.41 no.2
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• pp.508-519
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• 2024

In this study, in order to evaluate the possibility of using Jubak as a functional cosmetic material, evaluation of antioxidant activity according to fractions and anti-wrinkle efficacy in CCD-986sk cells, a human fibroblast, were conducted. As a result of confirming the antioxidant activity by measuring ABTS⁺ radical scavenging ability, Jubak's Ethyl Acetate fractions was found to be 75.5% at a concentration of 1,000 ㎍/ml, showing the highest antioxidant activity among the extraction solvents. The wrinkle improvement effect was confirmed by measuring the inhibitory activity of elastase and collagenase, and in both test results, Jubak's Ethyl Acetate fractions showed the highest efficacy at a concentration of 1,000 ㎍/ml. As a result of measuring the synthesis rate of pro-collagen type I in CCD-986sk cells induced by UVB, Jubak showed the highest efficacy in the order of Ethyl Acetate, Water, Acetonitrile, and Hexan fractions at the same concentration of 20 ㎍/ml. As a result of measuring the inhibition rate of MMP-1, a collagen degrading enzyme, all four solvent fractions showed an efficacy of more than 70% at 20 ㎍/ml. As a result of measuring the mRNA expression levels of pro-collagen type I, MMP-1, and MMP-3 in a real-time PCR experiment, the protein expression level of pro-collagen type I increased when treated with Jubak fractions compared to the UVB group alone. The mRNA expression levels of MMP-1 and MMP-3 were confirmed to be decreased, and Ethyl Acetate fractions was the most effective in improving wrinkles after the control group (EGCG). As a result, it was confirmed that the Ethyl Acetate fractions among Jubak's solvent fractions has an anti-wrinkle effect against photoaging caused by UVB stimulation, and is expected to be used as a natural material for cosmetics.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.109-119
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• 2024

This study was conducted to investigate the early life history by observing the egg development of Ladislavia taczanowskii in endangered fish and to use it as basic data for species conservation research. The broodstork used in the study was secured from the area of the Hongcheon River in Hongcheon-gun, Gangwon State. The broodstork, who was being raised in the laboratory, selected mature individuals in May 2021 and induced them to spawn by hormone injection. The size of the maturation egg was 1.50~1.79 (average 1.59±0.08, n=30) mm due to the circular invasive egg. The incubation time took 168 hours at 16.5℃ and 109 hours and 30 minutes at 25.5℃. Newly hatched larvae, the consonants had a total length of 5.55~6.31 mm (6.30±6.93, n=30) mm, and the mouth and anus did not open and had egg yolk. 5 days after hatching, the preflexion larvae had a total length of 9.91~10.8 (10.1±0.27, n=30) mm, and the mouth and anus opened, and feeding activities began. 8 days after hatching, the flexion larvae had a total length of 10.3~11.4 (10.8±0.38, n=30) mm, and the end of the vertebrae at the tail fin tip began to bend upward. 10 day after hatching, the postflexion larvae had a total length of 11.8~13.1 (12.3±0.43, n=30) mm, and the end of the vertebrae at the tail tip was completely bent at 45°. 18 days after hatching, the total length of the juveniles was 18.9~23.4 (20.4±1.69, n=30) mm, and the number of fins in each part was fin rays with 10 dorsal fins, 9 anal fins, 22 caudal fins, and 7 ventral fins. As a result of the study, the postflexion larvae showed differences in morphology from other Gobioninae fishes in the upper part of the tail's hypural, the shape of spots on the dorsal vertebrae, the vertical stripes developed on the head, and the irregularly deposited melanophore throughout the body.

• Journal of the Korean earth science society
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• v.45 no.1
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• pp.1-18
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• 2024

This study analyzed the effect of warming on PM_2.5 aerosol production in mid-latitude East Asia during June 2020 using PM_2.5 aerosol anomalies, which were identified by incorporating meteorological and climate data into the Weather Research Forecasting model coupled with Chemistry (WRF-Chem) model. The decadal temperature change trend over a 30-year period (1991-2020) in East Asia showed that recent warming has been greater in summer than in winter. Summer warming in East Asia generated low and high pressure in the lower and upper troposphere, respectively, over China. The boundary between the lower tropospheric low and upper tropospheric high pressure sloped along the terrain from the Tibetan Plateau to Korea. The eastern China, Yellow Sea, and Korean regions experienced a convergence of warm and humid southwesterly airflows originating from the East China Sea with the development of a northwesterly Pacific high pressure. In June 2020, the highest temperatures were observed since 1973 in Korea. Meanwhile, enhanced warming in East Asia increased the production of PM_2.5 aerosols that travelled long distances from eastern China to Korea. PM_2.5 anomalies, which were derived solely by inputting meteorological and climatic data (1991-2020) into the WRF-Chem model and excluding emission variations, showed a positive distribution extending from eastern China to South Korea across the Yellow Sea as well as over the Pacific Northwest. Thus, the contribution of warming to PM_2.5 aerosols in East Asia during June 2020 was more than 50%. In particular, PM_2.5 aerosols were transported from eastern China to Korea through the Yellow Sea, where the warm and humid southwesterly airflows implied wet scavenging of sulfate but promoted nitrate production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.304-312
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• 2023

Plant breeding is a time-consuming process, mainly due to the limited annual generational advancement. A speed breeding system, using LED light sources, has been applied to accelerate generational progression in various crops. However, detailed protocols applicable to soybeans are still insufficient. In this study, we report the optimized protocols for a speed breeding system comprising 12 soybean varieties with various maturity ecotypes. We investigated the effects of two light qualities (RGB ratio), three levels of light intensity (PPFD), and two soil conditions on the flowering time and development of soybeans. Our results showed that an increase in the red wavelength of the light spectrum led to a delay in flowering time. Furthermore, as light intensity increased, flowering time, average internode length, and plant height decreased, while the number of nodes, branches, and pods increased. When compared to agronomic soil, horticultural soil resulted in an increase of more than 50% in the number of nodes, branches, and pods. Consequently, the optimal conditions were determined as follows: a 10-hour short-day photoperiod, an equal RGB ratio (1:1:1), light intensity exceeding 1,300 PPFD, and the use of horticultural soil. Under these conditions, the average flowering time was found to be 27.3±2.48 days, with an average seed yield of 7.9±2.67. Thus, the speed breeding systems reduced the flowering time by more than 40 days, compared to the average flowering time of Korean soybean resources (approximately 70 days). By using a controlled growth chamber that is unaffected by external environmental conditions, up to 6 generations can be achieved per year. The use of LED illumination and streamlined facilities further contributes to cost savings. This study highlights the substantial potential of integrating modern crop breeding techniques, such as digital breeding and genetic editing, with generational shortening systems to accelerate crop improvement.

• Sim-seong Yeon-gu
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• v.27 no.1_2
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• pp.28-70
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• 2012

In Jungian psychology, creation myths regard as the story of unconscious and preconscious processes(projection of archaic identity) which describe not necessary the origin of our cosmos, but the origin of man's conscious awareness of the world. Therefore projections have nothing to do with matter itself but experience of one's own unconscious. Jung emphasizes importance to understand projection in individual's conscious experience rather than in philosophical doctrine. The purpose of this thesis is to explore unconscious process of creation myths with egg symbolism in clinical cases to present universal feature of Cosmic/alchemical egg. Psychologically, creation myths retold when human mind needs new order. Depending on the attitude of ego, it can be sudden expansion of consciousness or contamination of ego by unconscious. In this study, 'chaos(messa confusa)' in creation myths as archaic identity, experience of uroboros or infant, and nigredo state in alchemy. 'Separation of primordial parents' as beginning of consciousness refers to separatio operation in alchemical process. 'Light' as attainment of consciousness. Discussion of psychological meaning of egg starts with amplification which include the concept of cosmic/alchemical/philosophical egg. Egg symbolism in this study refers to emergence of egg, tapas/brooding of egg, and separation of egg. Emergence of egg as a state of preconscious totality, psychic wholeness conceived as the thing which came before the rise of ego consciousness. Discussion of conceptssuch as Shiva bindu, hiranyagharba, germ of gold, Tathāgatagarbha follows. 'Tapas/brooding of egg' as concentration of all psychic energy into one point for self reflection. Discussion includes The I Ching Hexagram 61, image of brooding egg identified with inner truth, Wonhyo's concept of jikwansasang, and Gnostic idea of Ennoia, introverted act of thinking, as well as the concept of 'Night Sea Journey'. 'Separation or hatching of egg' regarded as the idea of sudden illumination, Phanes, the shining God, and "sun-point," in alchemy. Birth of fledgling as birth of new personality. As a conclusion, psychological meaning of cosmic egg/creation myths is the story of separating from 'Not-I'(unconscious, object, undifferentiated) to 'I'(ego, subject, differentiated) which shares the same meaning as individuation process.

• Journal of The Korean Association For Science Education
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• v.44 no.2
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• pp.179-194
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• 2024

The aim of this study was to explore how a novice science teacher's epistemological framing, characterized from her modeling instruction, evolved over time. We observed that the teachers' framing changed over time, as she collaborated with researchers to plan, facilitate, and reflect on a series of lessons to support students' small-group scientific modeling. We tried to understand how such experiences contributed to the changes in her framing. One 8th grade science teacher with two years of teaching experience participated in the study. The teacher collaborated with researchers for four months to co-plan and facilitate 18 lessons that included small-group scientific modeling. She also engaged in cogenerative reflection on the lessons for 13 times. All of her lessons and reflections were video-recorded, transcribed, and qualitatively analyzed for the purpose of the study. Our findings showed that the teacher's epistemological framing, characterized from her interactions with students during modeling lessons, evolved during the study period: transitioning from an emphasis on students merely "filling in blanks" to prioritizing "constructing personal reasoning" and ultimately to focusing on the "social construction of scientific reasoning." The teacher's perception about what students are capable of changed, as she observed students during the modeling lessons, and this led to the shifts in her framing. Furthermore, through her engagement in planning, implementing, and reflecting on modeling lessons with researchers, she came to recognize the value of student collaboration in knowledge-building processes. These results can offer implications for supporting and studying teachers' epistemological framing and modeling-based teaching by partnering with them.

• Journal of the Korean earth science society
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• v.45 no.3
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• pp.203-213
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• 2024

This study aimed to investigate the seasonal patterns of multiple bar formation in summer and flattening in winter on the macrotidal Sinduri beach in Taean, and to understand the processes their formation and subsequent flattening. Beach profiling has been conducted regularly over the last four years using a VRS-GPS system. Surface sediment samples were collected seasonally along the transectline, and grain size analyses were performed. Tidal current data were acquired using a TIDOS current observation system during both winter and summer. The Sinduri macrotidal beach consists of two geomorphic units: an upper high-gradient beach face and a lower gentler sloped intertidal zone. High berms and beach cusps did not develop on this beach face. The approximately 400-m-wide intertidal zone comprises distinct 2-5 lines of multiple bars. Mean grain sizes of sand bars range from 2.0 to 2.75 phi, corresponding to fine sands. Mean sizes show shoreward coarsening trend. Regular beach-profiling survey revealed that the summer profile has a multi-barred morphology with a maximum of five bar lines, whereas, the winter profile has a non-barred, flat morphology. The non-barred winter profiles likely result from flattening by scour-and-fill processes during winter. The growth of multiple bars in summer is interpreted to be formed by a break-point mechanism associated with moderate waves and the translation of tide levels, rather than the standing wave hypothesis, which is stationary at high tide. The break-point hypothesis for multi-bars is supported by the presence of the largest bar at mean sea-level, shorter bar spacing toward the shore, irregular bar spacing, strong asymmetry of bars, and the 10-30 m shoreward migration of multi-bars.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.400-412
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• 2023

In this study, the biogeochemistry management (BGC-MAN) model was applied to North and South Korea pine and oak forest stands to evaluate the Net Primary Productivity (NPP), an indicator of forest ecosystem productivity. For meteorological information, historical records and East Asian climate scenario data of Shared Socioeconomic Pathways (SSPs) were used. For vegetation information, pine (Pinus densiflora) and oak(Quercus spp.) forest stands were selected at the Gwangneung and Seolmacheon in South Korea and Sariwon, Sohung, Haeju, Jongju, and Wonsan, which are known to have tree nurseries in North Korea. Among the biophysical information, we used the elevation model for topographic data such as longitude, altitude, and slope direction, and the global soil database for soil data. For management factors, we considered the destruction of forests in North and South Korea due to the Korean War in 1950 and the subsequent reforestation process. The overall mean value of simulated NPP from 1991 to 2100 was 5.17 Mg C ha^-1, with a range of 3.30-8.19 Mg C ha^-1. In addition, increased variability in climate scenarios resulted in variations in forest productivity, with a notable decline in the growth of pine forests. The applicability of the BGC-MAN model to the Korean Peninsula was examined at a time when the ecosystem process-based models were becoming increasingly important due to climate change. In this study, the data on the effects of climate change disturbances on forest ecosystems that was analyzed was limited; therefore, future modeling methods should be improved to simulate more precise ecosystem changes across the Korean Peninsula through process-based models.