• Journal of The Korean Association For Science Education
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• v.42 no.3
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• pp.371-381
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• 2022

This study causally investigates whether high school student with high science learning motivation becomes to achieve more or vice versa, and also how those two factors affect STEM career motivation. Research participants were 1st year students in a high school at Seoul. We surveyed their science learning motivation three times in the same time interval in the fall semester of 2021, and once a STEM career motivation in the third period. We collected data from 171 students with their mid-term and final exam scores, with which, we constructed and fitted an autoregressive cross-lagged model. The research model shows high measurement stability and fit indices. All the autoregressive and cross-lagged paths were statistically significant. However, standardized regression coefficients were larger in path from motivation to achievement compared to the opposite. Only science learning motivation shows significant direct effect on STEM career motivation, rather than achievement. For indirect effects, the first science learning motivation affected the final exam score and STEM career motivation, and the final exam score affected STEM career motivation. However, the final exam score did not have a total effect toward STEM career motivation. The result of this study shows reciprocal and cyclic causality between science learning motivation and achievement - in comparison, the effect of motivation for the opposite is larger than that of achievement. Also the result of this study strongly reaffirms the importance of science learning motivation. Instructional implications for strengthening science learning motivation throughout a semester was discussed, and a study for the longitudinal effect of science learning motivation and achievement in high school student toward future STEM vocational life was suggested.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.2
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• pp.212-223
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• 2022

For the remediation and restoration of contaminated sediment at the West Sea-Byeong dumping site, dredged materials was dumped in 2013, 2014, 2016, and 2017. The physicochemical properties and benthic fauna in surface sediments of the capping area (5 stations) and natural recovery area (2 stations) were analyzed annually from 2014 to 2020 to evaluate the capping effect of the dredged materials. The natural recovery area had a finer sediment with a mean particle size of 5.91-7.64 Φ, while the sediment in the capping area consisted of coarse-grained particles with a mean particle size of 1.47-3.01 Φ owing to the capping effect of dredged materials. Considering that the contents of organic matters (COD, TOC, and TN) and heavy metals in the capping area are approximately 50 % lower (p<0.05) than that in the natural recovery area, it is judged that there is a capping effect of dredged materials. As a result of analyzing macrobenthic assemblages, the number of species and ecological indices of the capping area were significantly lower than that of the natural recovery area (p<0.05). The number of species and ecological indices at the capping area were increased for the first four years after the capping in 2013 and 2014 and then tended to decrease thereafter. It is presumed that opportunistic species, which have rapid growth and short lifetime, appeared dominantly during the initial phase of capping, and the additory capping in 2016 and 2017 caused re-disturbance in the habitat environment. In the natural recovery and capping areas, Azti's Marine Biotic Index (AMBI) was evaluated as a fine healthy status because it maintained the level of 2^nd grades (Good), whereas Benthic Pollution Index (BPI) remained at the 1^st and 2^nd grade. Therefore, capping of dredged materials for remediation of contaminated sediment in the dumping site has the effect of reducing the pollution level. However, in terms of the benthic ecosystem, it is recommended that the recovery trend should be monitored long-term. Additionally, it is necessary to introduce an adaptive management strategy when expanding the project to remediate the contaminated sediment at the dumping area in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.1
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• pp.33-52
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• 2022

The History and Culture Park and the Lee Kun-hee Donation Hall will be built in Songhyeon-dong, Seoul. Political games from the Joseon Dynasty to the present greatly influenced the historicity of Songhyeon-dong. However, place analysis was limited to changes in landowners and land uses rather than a historical context. Therefore, this study analyzed the context in which the placeness of Songhyeon-dong changed according to the emergence of cultural hegemony using the perspective of modern cultural geography and comparative history. As a result of the analysis, cultural hegemony in historical transitions, such as Sinocentrism, maritime expansion, civil revolutions, imperialism, nationalism, popular art, and neoliberalism, was found to have created new intellectuals in Bukchon, including Songhyeon-dong, and influenced social systems and spatial policies. In this social relations, the placeness of Songhyeon-dong changed as follows. First, the founding forces of Joseon created pine forests as Bibo Forests to invocate the permanence of the dynasty. In the late Joseon dynasty, it was an era of maritime expansion, and as Joseon's yeonhaeng increased, a garden for the Gyeonghwasejok, who enjoyed the culture of the Qing dynasty, was built. Although pine forests and gardens disappeared due to the development of housing complexes as the population soared during the Japanese colonial era, Cha Gyeong's landscape aesthetics, which harmonized artificial gardens and external nature, are worth reinterpreting in modern times. Second, the wave of modernization created a new school in Bukchon and a boarding house in Songhyeon-dong owned by a pro-Japanese faction. Angukdongcheon-gil, next to Songhyeon-dong, was where thinkers who promoted civil revolution and national self-determination exchanged ideas. Songhyeon-dong, the largest boarding house, served as a residence for students to participate in the March 1st Movement and was the cradle of the resulting culture of student movements. The appearance of the old road is preserved, so it is a significant part of the regeneration of walking in the historic city center, connecting Gwanghwamun-Bukchon-Insadong -Donhwamunro. Third, from the cultural rule of the Government General of Joseon to the Military Government, Songhyeon-dong acted as a passage to western culture with the Joseon Siksan Bank's cultural housing and staff accommodations at the U.S. Embassy. Ancient and contemporary art coexisted in the surrounding area, so the modern and contemporary art market was formed. The Lee Kun-hee Donation Hall is expected to form a cultural belt for citizens with the gallery, Bukchon Hanok Village, the Craft Museum, and the Modern Museum of Art. Discourses and challenges are needed to recreate the place in harmony with the forests, gardens, the street of citizens' birth, history and culture park, the art museum, and the surrounding walking network.

• Journal of the Korean Orthopaedic Association
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• v.55 no.6
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• pp.503-510
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• 2020

Purpose: Bipolar hemiarthroplasty is used as an alternative to open reduction and internal fixation for unstable intertrochanteric fractures in elderly patients. Recent advances in medical systems and technologies have resulted in increased survival rates after intertrochanteric fractures of the femur, requiring selection of the appropriate femoral stems considering the mid- to long-term duration of survival. Hemiarthroplasty was performed for unstable intertrochanteric fractures using a double tapered quadrilateral femoral stem (C2 stem), and the clinical and radiological results were evaluated as a five-year follow-up post-surgery. Materials and Methods: From January 2004 to December 2013, 43 patients (43 hips) who underwent hemiarthroplasty with a C2 stem were enrolled in this study. Their mean age was 78.6 years (range, 70-84 years), and the mean follow-up period was 85.4 months (range, 60-96 months). During the follow-up period, clinical parameters, such as the changes in pain, walking ability, and functional status, were examined. Radiologically, changes in the proximal femur, such as osteoporosis and bone resorption of cortical bone, were noted. Complications that occurred during the follow-up period, such as dislocation and prosthetic features, were also reviewed. Results: Initially, the pain was relieved postoperatively, but it increased four years after surgery. The walking ability was reduced by two steps in nine patients after 60 months, and the Harris hip score was reduced significantly postoperatively after two to three years. Radiologically, cortical osteoporosis occurred in 14 patients. Five patients developed cortical bone resorption. Four of them showed nonunion of the trochanteric fracture fragments, and three of them suffered reverse oblique fractures. Conclusion: Careful selection considering the general health condition and remaining lifespan of the patient would be necessary for primary hip hemiarthroplasty using a 3C type cementless femoral stem for unstable intertrochanteric fractures in elderly patients with osteoporosis.

• Korean Journal of Ichthyology
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• v.34 no.2
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• pp.113-118
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• 2022

The feeding habits of sandfish, Arctoscopus japonicus were studied using 781 specimens collected by Eastern Sea Danish and gill net from January 2020 to December 2021 in the coastal waters of East Sea, Korea. The size of the specimens ranged from 14.8 to 25.4 cm in total length. A. japonicus were fed mainly on amphipods that constituted 54.7% in IRI. Cephalopods were the second largest prey component. The diets also include small quantities of euphausiids, crabs, shrimps, fishes, and worms. The diet composition of A. japonicus showed changes in season. The cephalopods feeding rate was highest in summer, whereas the proportion of euphausiids was higher in spring than in other seasons. The proportion of cephalopods has increased as the body size of A. japonicus increased, whereas the proportion of amphipods and euphausiids decreased gradually. As the body size of A. japonicus increased the mean weight of prey per the stomach (mW/ST) tended to increase significantly (One-way ANOVA, P<0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.4
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• pp.437-448
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• 2021

The purpose of this study is to analyze morphological characteristics of maxillary primary molar's root and root canal. 268 children aged 3 - 7 years (175 boys, 93 girls) who had CBCT (152 children) and 3D CT (116 children) taken in Seoul National University Dental Hospital from January 2006 to April 2020 were included. The number of roots and root canals were analyzed in 1002 teeth without any root resorption or periapical pathologies. Curvature, angulation, length of root and root canal, as well as cross-sectional shapes of the root canal were analyzed in 218 teeth. By using Mimics and 3-Matics software, volume, surface area, and volume ratio of root canal was analyzed in 48 teeth. More than half of maxillary primary molars have 3 roots and 3 root canals. The degree of symmetry of root canal type was about 0.63 (Cohen's kappa coefficient). The most frequent shape of roots and canals was linear in 1^st primary molars and curved in 2^nd primary molars. Angulation, length of root and root canals was the largest on palatal roots. Most teeth showed ovoid or round shapes at apex. The largest root canal volume, surface area, volume ratio was found in the palatal roots.

• Economic and Environmental Geology
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• v.55 no.4
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• pp.317-338
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• 2022

Physicochemical characteristics and evaluation were studied by subdividing the concretes, bricks and earth pipes on the site of the Japanese Ministry of General Affairs in Joseon Dynasty, known as modern architecture, into three periods. Concretes showed similar specific gravity and absorption ratio, and large amounts of aggregates, quartz, feldspar, calcite and portlandite were detected. Porosity of the 1907 bricks were higher than those of 1910 and 1950 bricks. All earthen pipe is similar, but the earlier one was found to be more dense. Bricks and earthen pipes are dark red to brown in color within many cracks and pores, but the matrix of the earthen pipe is relatively homogeneous. Quartz, feldspar and hematite are detected in bricks, and mullite is confirmed with quartz and feldspar in earthen pipes, so it is interpreted that the materials have a firing temperature about 1,000 to 1,100℃. Concretes showed similar CaO content, but brick and earthen pipe had low SiO₂ and high Al₂O₃ in the 1907 specimen. However, the materials have high genetic homogeneity based on similar geochemical behaviors. Ultrasonic velocity and rebound hardness of the concrete foundation differed due to the residual state, but indicated relatively weak physical properties. Converting the unconfined compressive strength, the 1st extended area had the highest mean values of 45.30 and 46.33 kgf/cm², and the 2nd extended area showed the lowest mean values (20.05 and 24.76 kgf/cm²). In particular, the low CaO content and absorption ratio, the higher ultrasonic velocity and rebound hardness. It seems that the concrete used in the constructions of the Japanese Ministry of General Affairs in Joseon Dynasty had similar mixing characteristics and relatively constant specifications for each year. It is interpreted that the bricks and earthen pipes were through a similar manufacturing process using almost the same raw materials.

• Industry Promotion Research
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• v.7 no.3
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• pp.27-42
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• 2022

Local education autonomy aims to improve the quality of life of local residents and to realize education considering local characteristics. For this purpose, it is necessary to strengthen the competency of local education administrative officials. This study intends to derive the competency of level 6 public officials who should play a central role in local education administrative officials, and to devise the subjects cluster and subjects of the long-term education program. The purpose of this study is to prepare a basic plan so that the education program for level 6 educational administrative officials can be developed in the future. For this study, an expert panel was composed of 20 people including education administrative officials and education program development experts. In addition, the Delphi survey was conducted three times to obtain opinions on the competency of level 6 educational administrative officials and the subjects cluster and subjects of the long-term education program. For the competency of level 6 educational administrative officials, the validity of the survey data was evaluated in the Delphi 1st survey and the validity of the revised data in the 2nd Delphi survey was conducted. And for the subjects cluster and subjects of the long-term education program for level 6 educational administrative officials, the validity of basic data was evaluated in the Delphi 2nd survey and the validity of the revised data in the 3rd Delphi survey was conducted. As a result, the competencies of level 6 educational administrative officials were extracted into nine competencies including coordination and integration competencies. And the long-term education program for level 6 educational administrative officials was developed with 13 subjects cluster and 43 subjects. And the relationship model between the competency of level 6 educational administrative officials and the subjects cluster and subjects of the long-term education program was derived. Based on the results of this study, it was proposed to operate a flexible curriculum for a long-term education program. In addition, the necessity of establishing a system that can reflect the educational training results in the actual educational field was suggested.

• Korean journal of applied entomology
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• v.24 no.2 s.63
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• pp.65-70
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• 1985

The locational preference of the brown planthopper (BPH) Nilaparvata lugens ($St{\aa}l$) and the whitebacked plant hopper (WBPH) Sogatella furcifera(Horvath) was studied on rice cultivars IR22 and IR36 as an integral part of subsequent research on insect-fungal pathogen relationships. The BPH was observed to stay consistently on the basal portion while the WBPH showed a general preference for the upper portion regardless of varieties, rice growth stages and insect population density levels. The habitat preference of both species (BPH and WBPH) was found not to be affected by the presence of the other species when both species are present on the same host plant Five rice cultivars with different reactions to BPH biotype 2 were used in the study on BPH-Rhizoctonia solani relationship: IR22 and TN1 (susceptible); Triveni and ASD7 (moderately resistant); and IR42 (resistant). Test plants were inoculated with R. solani (Kuhn) $3{\sim}4$days after insect infestation. Sheath blight disease severity/incidence was significantly higher in the treatment where BPH+R. solani were together than in the treatment with only the pathogen. Symptom expression of the disease in the BPH-pathogen combination was faster and mycelial growth was more profuse inducing the formation of more infection structures. Regardless of varietal reaction to BPH biotype 2, the degree of hopperburn was significantly higher in the combination of the two pests as compared with that of BPH alone. There could be a synergistic relationship between the insect pest and the pathogen indicated by a positive interaction between the two species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.3
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• pp.270-280
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• 1988

This experiment was conducted to evaluate the main effects and pleiotropic effects of two comparable isogenic lines for culm and spike length in hulled barley and observed various agronomic characteristics, yield and yield components under the conditions of heavy fertilizer application and high planting densities. Three isogenic lines, culm, spike and culm and spike, were planted and to obtain basic data for improving high-yielding and quality of hulled barley at Experiment Farm, Dankook Univ., Cheonan city in 1985. Differences of culm length between two comparable isogenic lines, short culmed line (SCL) and medium culmed line (MCL), in isogenic lines for culm length showed highly significant differences. And differences of spike length between two comparable isogenic lines, short spike line (SSL) and medium spike line (MSL), in isogenic lines for spike length showed highly significant differences. Differences of culm and spike length between two comparable isogenic lines, short culmed and spike line (SCSSL) and medium culmed and spike line (MCMSL), short culmed and spike line (SCSSL) and long culmed and spike line (LCLSL), in isogenic lines for culm and spike length showed highly significant differences. Characteristics affected highly by the genes of culm length in isogenic lines for culm length were heading days, the 1st and 2nd internode length, No. of grains per spike, No. of spikes/m$^2$, and one litre weight. Characteristics affected highly by the genes of spike length in isogenic lines for spike length were No. of spike nodes, heading days, maturity days, thousand grain weight and one litre weight. Characteristics affected highly by the genes of culm and spike length in isogenic lines for culm and spike length were No. of spike nodes, the 2nd, 3rd and 4th internode length, thousand grain weight and grain yield. Grain yield of SCL, MSL, MCMSL and SCSSL was more than grain yield of MCL, SSL, SCSSL and LCLSL, respectively. Maturity days of SCL, MSL, SCSSL and LSLSL were faster than maturity days of MCL, SSL, MCMSL and SCSSL, respectively.