• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.261-269
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• 2021

Without any validation of the incompressible assumption, most of previous studies on cavitation flow and its noise have utilized numerical methods based on the incompressible Reynolds Average Navier-Stokes (RANS) equations because of advantage of its efficiency. In this study, to investigate the effects of the flow compressibility on the Tip Vortex Cavitation (TVC) flow and noise, both the incompressible and compressible simulations are performed to simulate the TVC flow, and the Ffowcs Williams and Hawkings (FW-H) integral equation is utilized to predict the TVC noise. The DARPA Suboff submarine body with an underwater propeller of a skew angle of 17 degree is targeted to account for the effects of upstream disturbance. The computation domain is set to be same as the test-section of the large cavitation tunnel in Korea Research Institute of Ships and Ocean Engineering to compare the prediction results with the measured ones. To predict the TVC accurately, the Delayed Detached Eddy Simulation (DDES) technique is used in combination with the adaptive grid techniques. The acoustic spectrum obtained using the compressible flow solver shows closer agreement with the measured one.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.118-127
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• 2021

Recently, the public's interest in the air environment has increased, and public health is threatened by fine particulate matter. Furthermore, the government continues efforts to improve air quality by expanding the monitoring of air pollutants and reinforcing environmental standards. Since air quality differs depending on the region in the Korean Peninsula, it is currently necessary to identify the cause and search for influencing factors. In this study, the atmospheric environment and regional differences in cities located in the Chungnam Province were observed. As a research method, regression analysis was performed for weather conditions, such as temperature, wind speed, precipitation, and season and targeted at air pollutants, such as SO₂, NO₂, CO, O₃, PM₁₀, and PM_2.5, as well as heavy metals contained in particulate matter, such as Pb, Cd, Cr, Cu, Ni, As, Mn, Fe, Al, Ca, and Mg. In the case of PM₁₀, the concentrations of Mn(0.4884) in Cheonan, CO(0.3329) in Dangjin, and Mg(0.5691) in Seosan were highest. In the case of PM_2.5, Cheonan NO₂(0.4759), Dangjin CO(0.4128), and Seosan NO₂(0.3715) were significantly affected. In summary, the influencing factors vary according to the region in Chungnam province in terms of air quality, and there is a difference in the degree of contribution. Therefore, it is considered that the Korean government's management of air quality is required for each region.

• Journal of Korea Entertainment Industry Association
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• v.14 no.8
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• pp.513-523
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• 2020

This study has derived the patents of the technology that have been filed and registered so far to investigate the trends of virtual reality(VR) experience contents technology, and analyzed them focusing on core patent technologies. The patents of Korea, USA, Japan, Europe and PCT, which were released until June 2020, were targeted, and patent search was conducted using WISDOMAIN search DB. The keywords for patent search were related to experience technology using VR, and a total of 1,013 data were obtained after creating a search formula by combining the derived keywords. Among them, a total of 65 data were extracted from the result of selecting valid patents, and a political analysis was conducted on them. Looking at the overall application trend, most of Korean patent applications accounted for, and noise patents are system-related devices to implement VR technology. The United States and Europe are focused on developing augmented reality(AR) technology, the study found. The technology of VR experience has increased rapidly since 2017, and the technology growth stage is the period from the beginning to the growth stage. As a result of examining the valid patents related to VR experience, technology was searched in various fields such as rural tour, exhibition, education, and performance, and patents for contents writing and general virtual experience related technology were also searched. If we predict the possibility of development of VR industry in the future, it is necessary to respond to preemption of intellectual property rights by proceeding technology development and patent application for more diverse fields.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.53-62
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• 2023

The purpose of this study is to find an optimized imaging technique and evaluate its usefulness by comparing and analyzing the difference in contrast enhancement of lower extremity artery according to the patient's heart rate during lower extremity Computed Tomography Angiography examination. From January 2022 to August 22nd, 139 outpatients who visited Ajou University Hospital and underwent lower extremity angio CT examination were targeted. According to the heart rate, the groups were divided into four groups: A(HR ≤65), B(65 < HR < 80), C(80≤ HR). In addition, among patients with a heart rate of 65 or less, the heart rate was considered, and the scan was divided into D, E, F group with a delay time. The time of arrival of contrast medium and the average value of contrast enhancement were compared and analyzed. As a result of quantitative evaluation, B and C groups with a heart rate of more than 65 times had better HU values in the popliteal artery than A group (HR ≤ 65), and D group showed better HU improvement effects compared to A group (p<0.001). The comparative analysis with other groups was insignificant. The difference in heart rate affected the angiographic intensity of the lower extremities artery. Therefore, it is effective to apply the appropriate test timing for each patient by using the heart rate during the lower extremity angio CT Scan.

• Journal of Digital Policy
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• v.1 no.2
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• pp.9-15
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• 2022

The World Economic Forum has included Water-Energy-Food among the three major risk groups in the world, and Water-Energy-Food is related to the development strategies of countries and the lives of their citizens. This study calculates the combined Water-Energy-Food use efficiency in China for 2011-2020 based on the SBM-Malmquist index. The results show that the overall combined Water-Energy-Food efficiency in China is low, but shows an upward trend. There is a clear variability in the combined Water-Energy-Food utilization efficiency in China, with an overall geographic distribution pattern of East > Middle > West. Only Beijing and Shanghai have reached the real above effective nationwide, and all other provinces have inefficiency between input and output. The Malmquist index of integrated Water-Energy-Food utilization efficiency is 1.136, with an up ward trend, and technical efficiency and technological progress lead the improvement of integrated Water-Energy-Food utilization efficiency in China at the sametime. The Water-Energy-Food issue should be raised to a strategic level as soon as possible, and policy support should be provided for its development. Each region should establish a cross-regional coordinating body to formulate targeted measures according to the province's food production and water distribution, so as to promote economic transformation from sloppy development to green development as soon as possible.

• Korean Journal of Pharmacognosy
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• v.53 no.4
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• pp.226-233
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• 2022

Ephedra herbs are defined as stem of Ephedra sinica , Ephedra intermedia and Ephedra equisetina in the Korean Pharmacopoeia. It is important to use pure herbs to derive the safety and efficacy of herbal medicine. However, the identification of these herbs by conventional taxonomic methods is difficult. Recently, many studies have applied these DNA barcoding for the identification of herbal medicinal species using standard DNA markers. In this study, we report a case study in which the identification of Ephedra species was done by DNA barcoding. For identification of Ephedra species, 17 samples were collected, and a reference DNA barcode library was developed using 6 markers (rbcL, matK, ITS2, ycf1, ycf3, and rpoC2). To develop KASP-SNP markers, we selected 4 markers (ycf1, ycf3, rpl2, and rbcL), which were able to distinguish three Ephedra species. In the result, the specific markers for each of the three Ephedra were clustered into FAM-positive section, whereas non-targeted plants were clustered either HEX-positive or negative section. Therefore, we have developed KASP assay that allow rapid and easy Ephedra species identification using three KASP markers.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.4
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• pp.239-253
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• 2022

Epithelial-mesenchymal transition (EMT) is known to be involved in airway remodeling and fibrosis of bronchial asthma. However, the molecular mechanisms leading to EMT have yet to be fully clarified. The current study was designed to reveal the potential mechanism of microRNA-21 (miR-21) and poly (ADP-ribose) polymerase-1 (PARP-1) affecting EMT through the PI3K/AKT signaling pathway. Human bronchial epithelial cells (16HBE cells) were transfected with miR-21 mimics/inhibitors and PARP-1 plasmid/small interfering RNA (siRNA). A dual luciferase reporter assay and biotin-labeled RNA pull-down experiments were conducted to verify the targeting relationship between miR-21 mimics and PARP-1. The migration ability of 16HBE cells was evaluated by Transwell assay. Quantitative real-time polymerase chain reaction and Western blotting experiments were applied to determine the expression of Snail, ZEB1, E-cadherin, N-cadherin, Vimentin, and PARP-1. The effects of the PI3K inhibitor LY294002 on the migration of 16HBE cells and EMT were investigated. Overexpression of miR-21 mimics induced migration and EMT of 16HBE cells, which was significantly inhibited by overexpression of PARP-1. Our findings showed that PARP-1 was a direct target of miR-21, and that miR-21 targeted PARP-1 to promote migration and EMT of 16HBE cells through the PI3K/AKT signaling pathway. Using LY294002 to block PI3K/AKT signaling pathway resulted in a significant reduction in the migration and EMT of 16HBE cells. These results suggest that miR-21 promotes EMT and migration of HBE cells by targeting PARP-1. Additionally, the PI3K/AKT signaling pathway might be involved in this mechanism, which could indicate its usefulness as a therapeutic target for asthma.

• Journal of Ginseng Research
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• v.46 no.2
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• pp.235-247
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• 2022

Background: Ginsenoside Rg3 is one of the main active ingredients in ginseng. Here, we aimed to confirm its protective effect on the heart function in transverse aortic coarctation (TAC)-induced heart failure mice and explore the potential molecular mechanisms involved. Methods: The effects of ginsenoside Rg3 on heart and mitochondrial function were investigated by treating TAC-induced heart failure in mice. The mechanism of ginsenoside Rg3 for improving heart and mitochondrial function in mice with heart failure was predicted through integrative analysis of the proteome and plasma metabolome. Glucose uptake and myocardial insulin sensitivity were evaluated using micro-positron emission tomography. The effect of ginsenoside Rg3 on myocardial insulin sensitivity was clarified by combining in vivo animal experiments and in vitro cell experiments. Results: Treatment of TAC-induced mouse models with ginsenoside Rg3 significantly improved heart function and protected mitochondrial structure and function. Fusion of metabolomics, proteomics, and targeted metabolomics data showed that Rg3 regulated the glycolysis process, and Rg3 not only regulated glucose uptake but also improve myocardial insulin resistance. The molecular mechanism of ginsenoside Rg3 regulation of glucose metabolism was determined by exploring the interaction pathways of AMPK, insulin resistance, and glucose metabolism. The effect of ginsenoside Rg3 on the promotion of glucose uptake in IR-H9c2 cells by AMPK activation was dependent on the insulin signaling pathway. Conclusions: Ginsenoside Rg3 modulates glucose metabolism and significantly ameliorates insulin resistance through activation of the AMPK pathway.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.151-168
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• 2021

This study compared and analyzed the effect of the burden of household expenditure in the metropolitan and non-metropolitan areas on the intention to childbirth intention to married women using a panel logit model. To this end, this analysis targeted married women aged 25 to 39 who are highly likely to be fertile. The main results are as follows; First of all, it was confirmed that the economic power of spouse can be an important factor in the childbirth intention regardless of region. Second, it was found that the higher the satisfaction of marriage had a positive effect on the childbirth intention, and also higher the value that children must have, the higher the childbirth intention. Third, it was confirmed that the burden of household expenditure is the most important factor in the willingness to childbirth intention, excluding factors such as the number of existing children. In particular, the burden on education spending in both the capital region and non-capital region was found to be a key reason for the decrease in the childbirth intention. Lastly, the burden of household expenditure showed different effects on childbirth intention on depending on the region. Specifically, in the capital region, medical spending and loans had a greater impact, while, in the non-capital region, transportation and communication costs had a greater impact on childbirth intentions. Through the results, this study confirmed the implication that easing the burden on household expenditure is continuously necessary to enhance childbirth, and that discriminatory policy approaches are required depending on the area of residence.

• Journal of Korea Entertainment Industry Association
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• v.14 no.7
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• pp.439-446
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• 2020

This study aimed at developing a convergence education program about skin care and social welfare with the purpose of operating liberal arts courses to foster the creativity and character building of university students and the development findings are as follows. The name of the developed course is "beauty treatment welfare and community service" and details were developed for the course overview, goals of the course, textbooks, course management, assignments, and assessment. The lesson goals of this course are character building by fostering creative and outstanding individuals demanded by the society and equipped with the basic knowledge of majors like skin care and social welfare as well as the capability to share and consider through service learning related education for the increase in convergence critical thinking skills and the convergence of skin care and social welfare. The details of the course comprised of introduction about the course, understanding the concept of convergence, understanding the concepts of skin care and social welfare, convergent thinking education and practicum, and education about service learning performance sharing meeting. The service learning is targeted on the socially disadvantaged, such as children and elders, and students can engage in service twice a week with 3 hours for each service session. The assessment is evaluated with midterm (30%), final exam (30%), report (20%), and attendance (20%). This study stresses importance on the development of a convergence education program for skin care and social welfare, which are still undeveloped while convergence education is expanding in university, and with this research as the start, it is anticipated for various approaches to be actively implemented about convergence education in the field of beauty treatment.