• Korean Journal of Radiology
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• v.22 no.5
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• pp.782-791
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• 2021

Objective: To evaluate the signal intensity of the periosteum using ultrashort echo time pulse sequence with three-dimensional cone trajectory (3D UTE) with or without fat suppression (FS) to distinguish from artifacts in porcine tibias. Materials and Methods: The periosteum and overlying soft tissue of three porcine lower legs were partially peeled away from the tibial cortex. Another porcine tibia was prepared as three segments: with an intact periosteum outer and inner layer, with an intact periosteum inner layer, and without periosteum. Axial T1 weighted sequence (T1 WI) and 3D UTE (FS) were performed. Another porcine tibia without periosteum was prepared and subjected to 3D UTE (FS) and T1 WI twice, with positional changes. Two radiologists analyzed images to reach a consensus. Results: The three periosteal tissues that were partially peeled away from the cortex showed a high signal in 3D UTE (FS) and low signal on T1 WI. 3D UTE (FS) showed a high signal around the cortical surface with an intact outer and inner periosteum, and subtle high signals, mainly around the upper cortical surfaces with the inner layer of the periosteum and without periosteum. T1 WI showed no signal around the cortical surfaces, regardless of the periosteum state. The porcine tibia without periosteum showed changes in the high signal area around the cortical surface as the position changed in 3D UTE (FS). No signal was detected around the cortical surface in T1 WI, regardless of the position change. Conclusion: The periosteum showed a high signal in 3D UTE and 3D UTE FS that overlapped with artifacts around the cortical bone.

• Journal of Practical Engineering Education
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• v.16 no.2
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• pp.129-141
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• 2024

In recent times, there has been a shift towards student-centered higher education policies, leading to a growing interest among universities to improve students' learning outcomes. To aid in this endeavor, this study aims to provide guidance for University K to enhance their learning outcome management by comparing and analyzing their learning outcome indicators with those of other domestic and foreign universities. The study examined detailed measurement questions from major learning outcome measurement tools such as AHELO, NSSE, and CLA+. Upon comparison and analysis of University K's major learning outcome indicators with those of other universities, it was found that most of the indicators overlapped. However, some indicators such as student support/facilities for learning, instructor quality, and communication were absent from University K. Therefore, it is crucial to decide whether to add these indicators to the existing learning outcomes or to confirm them through other surveys. Moreover, even for the same indicator, some indicators with different measurement need to consider changing the measurement.

• The Korea Journal of Herbology
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• v.39 no.3
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• pp.37-47
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• 2024

Objectives : Because predicting the potential efficacy and mechanisms of Korean medicines is challenging due to their high complexity, employing an approach based on network pharmacology could be effective. In this study, network pharmacological analysis was utilized to anticipate the effects of YunPye-Hwan (YPH) in treating Chronic obstructive pulmonary disease (COPD). Methods : Compounds and their related target genes of YPH were gathered from the TCMSP and PubChem databases. These target genes of YPH were subsequently compared with gene sets associated with COPD to assess correlation. Next, core genes were identified through a two-step screening process, and finally, functional enrichment analysis of these core genes was conducted using both Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathways. Results : A total of 15 compounds and 437 target genes were gathered, resulting in a network comprising 473 nodes and 14,137 edges. Among them, 276 genes overlapped with gene sets associated with COPD, indicating a significant correlation between YPH and COPD. Functional enrichment analysis of the 18 core genes revealed biological processes and pathways such as "miRNA Transcription," "Nucleic Acid-Templated Transcription," "DNA-binding Transcription Factor Activity," "MAPK signaling pathway," and "TNF signaling pathway" were implicated. Conclusion : YPH exhibited significant relevance to COPD by modulating cell proliferation, differentiation, inflammation, and cell death pathways. This study could serve as a foundational framework for further research investigating the potential use of YPH in the treatment of COPD.

• Korean Journal of Radiology
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• v.21 no.6
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• pp.660-669
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• 2020

Objective: To evaluate the accuracy of a deep learning-based automated segmentation of the left ventricle (LV) myocardium using cardiac CT. Materials and Methods: To develop a fully automated algorithm, 100 subjects with coronary artery disease were randomly selected as a development set (50 training / 20 validation / 30 internal test). An experienced cardiac radiologist generated the manual segmentation of the development set. The trained model was evaluated using 1000 validation set generated by an experienced technician. Visual assessment was performed to compare the manual and automatic segmentations. In a quantitative analysis, sensitivity and specificity were calculated according to the number of pixels where two three-dimensional masks of the manual and deep learning segmentations overlapped. Similarity indices, such as the Dice similarity coefficient (DSC), were used to evaluate the margin of each segmented masks. Results: The sensitivity and specificity of automated segmentation for each segment (1-16 segments) were high (85.5-100.0%). The DSC was 88.3 ± 6.2%. Among randomly selected 100 cases, all manual segmentation and deep learning masks for visual analysis were classified as very accurate to mostly accurate and there were no inaccurate cases (manual vs. deep learning: very accurate, 31 vs. 53; accurate, 64 vs. 39; mostly accurate, 15 vs. 8). The number of very accurate cases for deep learning masks was greater than that for manually segmented masks. Conclusion: We present deep learning-based automatic segmentation of the LV myocardium and the results are comparable to manual segmentation data with high sensitivity, specificity, and high similarity scores.

• Journal of the Earthquake Engineering Society of Korea
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• v.28 no.3
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• pp.129-139
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• 2024

In this study, the SBC system, a new mechanical joint method, was developed to improve the constructability of precast concrete (PC) beam-column connections. The reliability of the finite element analysis model was verified through the comparison of experimental results and FEM analysis results. Recently, the intermediate moment frame, a seismic force resistance system, has served as a ramen structure that resists seismic force through beams and columns and has few load-bearing walls, so it is increasingly being applied to PC warehouses and PC factories with high loads and long spans. However, looking at the existing PC beam-column anchorage details, the wire, strand, and lower main bar are overlapped with the anchorage rebar at the end, so they do not satisfy the joint and anchorage requirements for reinforcing bars (KDS 41 17 00 9.3). Therefore, a mechanical joint method (SBC) was developed to meet the relevant standards and improve constructability. Tensile and bending experiments were conducted to examine structural performance, and a finite element analysis model was created. The load-displacement curve and failure pattern confirmed that both the experimental and analysis results were similar, and it was verified that a reliable finite element analysis model was built. In addition, bending tests showed that the larger the thickness of the bolt joint surface of the SBC, the better its structural performance. It was also determined that the system could improve energy dissipation ability and ductility through buckling and yielding occurring in the SBC.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.62-69
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• 2012

Purpose: The present study has an objective of effectively separating and making observations on a portion of radiopharmaceutical excreted via digestive organ to remain in the organ and invade a heart shadow. Materials and methods: When heart shadow is blocked by the organ in tests during a resting phase and a loaded phase, additional images were obtained using immobilization device. The immobilization devices were used to tilt the upper body forward from supine position. Results: In the reconstructed image for the separated case, as compared with the case where a part of organ is overlapped with heart, in terms of an overall mean value for each parameter, the end-diastolic volume increased by 2.75 mL, the end-systolic volume decreased by 3.16 mL, the left ventricle cardiac coefficient increased by 3.58%, and the area of defect region decreased by 3.58 and 3.92 cm for loading and resting phase, respectively. Conclusions: In the present study with myocardial perfusion SPECT, overlapped areas of heart and other organs could be effectively separated and visualization by the use of an immobilization device.

• Journal of Preventive Medicine and Public Health
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• v.23 no.1 s.29
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• pp.98-105
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• 1990

In order to fine out the relationship between traffic accidents and atmospheric phenomena, we have analyzed 2,562 cases, one tenth of the total traffic accidents occurred in Taegu city for a year in 1988. The meteorological elements observed by Taegu Weather Bureau were used. It was divided into two largy categories : the patterns of accident as human injuries and destructions of car. When the accidents were overlapped in each other, it was considered as human injury. Human injuries were subdivided into three parts : death, severe wound and slight in, when more then two cases were overlapped, we choiced severe damage. The average number of daily traffic accidents including human injuries were lowest in winter of four seasons. The accident patterns in accordance with the seasons showed statistically significant difference. The frequency was the highest as 3.3 cases in an hour at $25.1-30.0^{\circ}C$ of atmospheric temperature, the rate of human injury showed the increase by the increased temperature. But there were not significant. Also it was the highest as 3.7 cases in less than 31% of humidity and the rate of human injury as the highest at 41-50%, but not significant. And it was the increasing tendency as wind speed increase, and the rate of human injury was the highest at 6.1-7.0 m/sec, but it was not significant. In relation to precipitation, and visibility, were the highest as 5.4 cases at 5.1-10.0 mm of rainfall, the rate of human injury was increased by the increased precipitation and showed statistically significant. And it was highest within 6 Km of visibility, but the rate of the human injury was the lowest within same distance, and also showed significance. The accidents were higher with snow on the road, but the rate of human injury was comparatively lower, but no significance.

• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.263-275
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• 2012

Jurassic Daebo biotite granites, known as one of the main stone resources in the country, are widely and away distributed in the Pocheon and Yangju areas of the mid Gyeonggi massif. The objects of the study are mainly to reveal the unique characteristics of grain size, rock color, mineral composition, physical property and fracture system from the above biotite granites. Biotite granites from the Pocheon area (PG) and Yangju area (YG) are represented by coarse-grained and light gray, and medium to coarse-grained and grayish to light gray, respectively. In modes, main minerals of Qz+Af+Pl (quartz+alkali feldspar+plagioclase) are more increased in the PG, and accessories of biotite are more increased in the YG, which differences can cause the PG more bright light gray than the YG. Specific gravity (SG) shows somewhat more increasing in the YG than the PG. These differences can be caused by more increasing in biotite contents of higher specific gravity compared to the major minerals in the former than the latter. Absorption ratio (AR) and porosity (PR) of the PG and YG show the same values of 0.33 % and 0.86 %, respectively. In the correlations, PR vs SG and AR vs PR show gradually negative and distinctly positive trends, respectively. Compressive strength (CS) and tensile strength (TS) show increasing in the PG (CS: 1,775 $kg/cm^2$, TS: 87 $kg/cm^2$) than the YG (CS: 1,647 $kg/cm^2$, TS: 79 $kg/cm^2$). These strength characteristics could be attributed to the inherent rock textures of them. Abrasive hardness (AH) also shows a little increasing in PG, which can be caused by increase in quartz contents having higher hardness than the other major minerals. Orientations of fracture sets from the PG and YG were compared with those of vertical rift and grain planes in Mesozoic granites of the country. From the overlapped diagram, the distribution pattern between fracture sets and above vertical planes suggests that microcrack systems developed in Mesozoic granites in Korea occur also in the Daebo biotite granite bodies of the mid Gyeonggi massif. From the relation diagram showing the characteristics of fracture patterns for the above two area, PG and YG may have more potentiality for dimension and non-dimension stone resources, respectively.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.173-184
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• 2016

Knowledge of the relationships among interspecific competition, spatial distributions and ecological niches plays an important role in understanding biogeographical distribution patterns of species. In this study, the distributional characteristics and ecological niches of the three Viperidae species (Gloydius ussuriensis, G. brevicaudus, and G. saxatilis) in South Korea were determined based on observation data and species distribution model. The effects of interspecific competition on geographical distribution and the division of the ecological niches of the vipers were also examined based on the models of predicted species distribution. The results showed that altitude was the most important environmental variable for their distribution, and the altitudes at which these snakes were distributed correlated with the climate of that region. Although interspecific ecological niches are quite overlapped, their predicted distribution patternsvary by the Taebaek Mountains. When overlaying the distribution models, most of the overlapping habitats were forest areas, which were relatively less overlapped than were the entire research areas. Thus, a parapatric distribution pattern was expected. The abundance of species occurring sympatrically was positively correlated with each other, indicating the lack of serious interspecies competition in this region. In conclusion, although the three Viperidae species in South Korea occupy similar ecological niches, these snakes exhibit parapatric distribution patterns without direct competition. Further research on various geographic variables (e.g., altitude, microhabitat characteristics) using relatively fine grid sizes, as well as further detailed ecological and behavioral research, is needed to determine the causative factors for the parapatric distribution pattern.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.3
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• pp.1-11
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• 2012

This study focused on establishing a natural rainwater circulation system using rainwater meant for relatively large urban development projects such as a new town development. In particular, when the location selection techniques for individual elements of a natural rainwater circulation system are developed for the integrated rainwater management, changes in hydrological environment will be minimized and the natural water circulation would be restored to realize the low impact development (LID). In that case, not only the excess will be reduced but water space and green areas in a city would also increase to improve the urban sustainability. First of all, there were five elements selected for the location selection of a rainwater circulation system intended for the integrated rainwater management: rainwater collection, infiltration, filtration, retention and movement spaces. After generating these items, the location selection items and criteria were defined for each of the five elements. For a technique to apply the generated evaluation items and criteria, a grid cell analysis was conducted based m the suitability index theory, and thematic maps were overlapped through suitability assessment of each element and graded based on the suitability index. The priority areas were identified for each element. The developed technique was applied to a site where Gim-cheon Innovation City development is planned to review its feasibility and limitations. The combined score of the overlapped map for each element was separated into five levels: very low, low, moderate, high and very high. Finally, it was concluded that creating a rainwater circulation system conceptual map m the current land use plan based on the outcome of the application would be useful in building a water circulation system at the de1ailed space planning stage after environmental and ecological planning. Furthermore, we use the results of this study as a means for environment-friendly urban planning for sustainable urban development.