• Journal of Korean Society of Disaster and Security
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• v.16 no.2
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• pp.85-98
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• 2023

Flood is one of the most frequent natural disasters worldwide. In Korea, the probability of urban flooding is greatly increasing due to complex factors such as global warming, an increase in impervious areas, and limitations in expanding water supply facilities in existing urban areas. However, large-scale civil engineering works to prevent urban inundation are socially and economically difficult to obtain national consent. Recently the importance of resilience, which is the ability to return to the original state after a disaster through rapid recovery while preparing for natural disasters to a level that the local community can afford socially and economically, is increasing. Accordingly, various studies on urban resilience have been conducted, but the resilience measurement method related to the lifeline that provides essential services of the city is insufficient. However, among lifelines, road networks are important facilities for the transportation of recovery resources and rapid recovery in the event of a natural disaster, so road networks are a major factor that must be considered when measuring the degree of recovery of a city in the field of natural disasters. Therefore, this study proposes a recovery evaluation method considering the characteristics of resilience and road networks in the urban flooding field and analyzes the effect of road networks on urban resilience.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.82-82
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• 2020

염증 (Inflammation)은 물리적인 상처나 세균감염이 되었을 때 손상된 조직을 재생하고 신체를 방어하기 위해 일어나는 선천성 면역반응으로 알려져 있다. 주로 선천면역을 담당하는 대식세포는 lipopolysaccharide, reactive oxygen species와 cytokine 등에 의해 활성화되어 tumor necrosis factor-α. interleukin-1β, interleukin-6 등 염증인자들의 생성에 관여한다. 특히, 산화질소는 superoxide 음이온과 쉽게 반응하고 peroxynitrite와 같은 독성이 강한 산화제를 생성하여 단백질 및 지질의 과산화를 유도하고 세포독성을 일으키는 것으로 보고되고 있다. 따라서 본 연구에서는 항산화 및 항염증 소재를 탐색하기 위해 오미자 (Schisandra chinensis), 꾸지뽕 (Cudrania tricuspidata)을 이용하여 항산화 활성을 평가하고자 하였으며, 세포주를 활용한 세포독성 및 항염증 활성을 확인하고자 하였다. 본 연구는 전북 순창군에서 재배된 오미자, 꾸지뽕을 열 건조(60℃) 통해 건조한 후 분말화하였다. 최적 추출 조건 선정을 위해 다양한 용매 (열수, 증류수, 주정 20, 40, 60%), 온도 (25, 40, 60, 80℃) 및 시간 (1, 2, 3, 4, 5 h) 조건에서 추출된 추출물의 총 폴리페놀 함량을 비교함으로써 최적 조건을 선정하였다. 오미자와 꾸지뽕의 DPPH 및 ABTS radical 소거 활성, 총 플라보노이드 함량을 확인하여 항산화능 및 기능성 성분 함량을 평가하였다. 또한 대식세포주인 Raw 264.7을 활용하여 MTT assay, 산화질소 생성 억제 활성을 확인하여 세포독성 및 항염증 활성을 평가하였다. 실험 결과, 오미자 및 꾸지뽕은 각각 주정 40%, 60℃ 그리고 증류수, 60℃에서 추출 시 가장 높은 총 폴리페놀 함량 (약 98.3 mg GAE/g 및 88.2 mg GAE/g)을 함유하며, DPPH 라디칼 소거 활성은 약 44.6% 및 24.4%, ABTS 라디칼 소거 활성은 약 30.3% 및 40.8%로 확인되었다. 총 플라보노이드 함량은 약 21.80 mg QE/g 및 35.68 mg QE/g으로 확인되었다. 또한 오미자 및 꾸지뽕 기능성 추출물을 100 ug/mL 처리 시 세포 독성이 나타나지 않는 것으로 확인되었으며, NO 생성량을 약 56.3% 및 21.7% 저감시켜 항염증 효능을 나타내는 것으로 확인되었다.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.2
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• pp.61-77
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• 2024

The purpose of this study was to develop a method for rapidly diagnosing urban thermal comfort using Unmanned Aerial Vehicle (UAV) based data. The research was conducted at Changwon National University's College of Engineering site and Yongji Park, both located in Changwon, Gyeongsangnam-do. Baseline data were collected using field measurements and UAVs. Specifically, the study calculated field measurement-based thermal comfort indices PET and UTCI, and used UAVs to create and analyze vegetation index (NDVI), sky view factor (SVF), and land surface temperature (LST) images. The results showed that UAV-predicted PET and UTCI had high correlations of 0.662 and 0.721, respectively, within a 1% significance level. The explanatory power of the prediction model was 43.8% for PET and 52.6% for UTCI, with RMSE values of 6.32℃ for PET and 3.16℃ for UTCI, indicating that UTCI is more suitable for UAV-based thermal comfort evaluation. The developed method offers significant time-saving advantages over traditional approaches and can be utilized for real-time urban thermal comfort assessment and mitigation planning

• Journal of the Korean earth science society
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• v.45 no.2
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• pp.111-120
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• 2024

Cloud coverage is a key factor in determining whether to proceed with observations. In the past, human judgment played an important role in weather evaluation for observations. However, the development of remote and robotic observation has diminished the role of human judgment. Moreover, it is not easy to evaluate weather conditions automatically because of the diverse cloud shapes and their rapid movement. In this paper, we present the development of a cloud monitoring program by applying a machine learning-based Python module "cloudynight" on all-sky camera images obtained at Miryang Arirang Astronomical Observatory (MAAO). The machine learning model was built by training 39,996 subregions divided from 1,212 images with altitude/azimuth angles and extracting 16 feature spaces. For our training model, the F1-score from the validation samples was 0.97, indicating good performance in identifying clouds in the all-sky image. As a result, this program calculates "Cloudiness" as the ratio of the number of total subregions to the number of subregions predicted to be covered by clouds. In the robotic observation, we set a policy that allows the telescope system to halt the observation when the "Cloudiness" exceeds 0.6 during the last 30 minutes. Following this policy, we found that there were no improper halts in the telescope system due to incorrect program decisions. We expect that robotic observation with the 0.7 m telescope at MAAO can be successfully operated using the cloud monitoring program.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.2
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• pp.171-180
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• 2024

The endotoxin test is based on the reaction between Limulus Amebocyte Lysate (LAL) and the lipopolysaccharides of Gram-negative bacteria. In this study, we sought to identify factors that interfere with the LAL testing of radiopharmaceuticals and evaluated acceptable ranges. A gel-clot LAL test and a chromogenic LAL test were used as endotoxin tests. We compared the performances of the Endosafe^Ⓡ LAL and recombinant Endosafe^Ⓡ Recombinant Cascade Reagent (rCR) cartridges for the chromogenic test. The factors that interfered with ⁶⁸Ga-DOTATOC injection were pH, 4-(2-hydroxyethyl) piperazine-1-ethanesulfonic acid (HEPES) buffer, and organic solvents, especially ethanol. However, interference by these factors was overcome by diluting the ⁶⁸Ga-DOTATOC injection tenfold. In addition, no interference was observed at pH values between 4 and 8, at a HEPES concentration of 2,000 ㎍/mL, or an ethanol concentration of <1%. Furthermore, results showed that interfering factors had similar effects on the performances of the Endosafe^Ⓡ LAL and Endosafe^Ⓡ rCR cartridges. The results of this study are expected to be useful for evaluating factors that interfere with the endotoxin testing of new radiopharmaceuticals.

• Information Systems Review
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• v.21 no.4
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• pp.47-68
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• 2019

As cloud services and deployment models become diverse, there are a growing number of cloud computing selection options. Therefore, financial companies need a methodology to select the appropriated cloud for each financial computing system. This study adopted the Balanced Scorecard (BSC) framework to classify factors for the introduction of cloud computing in financial companies. Using Analytic Hierarchy Process (AHP), the evaluation items are layered into the performance perspective and the cloud consideration factor and a comprehensive decision model is proposed. To verify the proposed research model, a system of financial company is divided into three: account, information, and channel system, and the result of decision making by both financial business experts and technology experts from two financial companies were collected. The result shows that some common factors are important in all systems, but most of the factors considered are very different from system to system. We expect that our methodology contributes to the spread of cloud computing adoption.

• Journal of The Korean Society of Clinical Toxicology
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• v.21 no.2
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• pp.135-142
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• 2023

Purpose: In patients with glufosinate poisoning, severe neurological symptoms may be closely related to a poor prognosis, but their appearance may be delayed. Therefore, this study aimed to determine whether the Acute Physiology and Chronic Health Evaluation II (APACHE II) score could predict the neurological prognosis in patients with glufosinate poisoning who present to the emergency room with alert mental status. Methods: This study was conducted retrospectively through a chart review for patients over 18 years who presented to a single emergency medical center from January 2018 to December 2022 due to glufosinate poisoning. Patients were divided into groups with a good neurological prognosis (Cerebral Performance Category [CPC] Scale 1 or 2) and a poor prognosis (CPC Scale 3, 4, or 5) to identify whether any variables showed significant differences between the two groups. Results: There were 66 patients (67.3%) with good neurological prognoses and 32 (32.8%) with poor prognoses. In the multivariate logistic analysis, the APACHE II score, serum amylase, and co-ingestion of alcohol showed significant results, with odds ratios of 1.387 (95% confidence interval [CI], 1.027-1.844), 1.017 (95% CI, 1.002-1.032), and 0.196 (95% CI, 0.040-0.948), respectively. With an APACHE II score cutoff of 6.5, the AUC was 0.826 (95% CI, 0.746-0.912). The cutoff of serum amylase was 75.5 U/L, with an AUC was 0.761 (95% CI, 0.652-0.844), and the AUC of no co-ingestion with alcohol was 0.629 (95% CI, 0.527-0.722). Conclusion: The APACHE II score could be a useful indicator for predicting the neurological prognosis of patients with glufosinate poisoning who have alert mental status.

• Journal of Service Research and Studies
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• v.14 no.1
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• pp.108-123
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• 2024

In particular, as the current educational institutions are becoming more competitive, universities need to make efforts to survive the fierce competition by improving their service qualities. In this situation, this study was conducted to confirm the effect of international students' evaluation of university service quality on university loyalty through university satisfaction and service engagements, And several implications can be suggested as follows. First, the dimensions of university service quality were identified as important factors that had a great influence on the university satisfaction of international students. Among the service quality dimensions, support services related to international students were found to be the most important variable in university satisfaction. The school's efforts to solve the inconvenience of international students and the grievances of students who feel difficulties that their own students do not feel are considered a very important factor in the satisfaction of international students. Second, it was found that international students' class engagement or friendship engagement can be increased through satisfaction with the school, and eventually, the increased engagements affect university loyalty. In particular, it has been verified that for international students, the loyalty of the school can be increased by establishing friendships with students from various countries and participating in various school programs. Finally, according to the purposes of studying abroad, the difference was confirmed between the groups studying for academic development and better employment and the group employed for overseas experience and immigration.

• Korean Journal of Radiology
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• v.21 no.12
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• pp.1317-1325
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• 2020

Objective: The aim of this study was to prospectively evaluate whether liver stiffness (LS) assessments, obtained by two-dimensional (2D)-shear wave elastography (SWE) with a propagation map, can evaluate liver fibrosis stage using histopathology as the reference standard. Materials and Methods: We prospectively enrolled 123 patients who had undergone percutaneous liver biopsy from two tertiary referral hospitals. All patients underwent 2D-SWE examination prior to biopsy, and LS values (kilopascal [kPa]) were obtained. On histopathologic examination, fibrosis stage (F0-F4) and necroinflammatory activity grade (A0-A4) were assessed. Multivariate linear regression analysis was performed to determine the significant factors affecting the LS value. The diagnostic performance of the LS value for staging fibrosis was assessed using receiver operating characteristic (ROC) analysis, and the optimal cut-off value was determined by the Youden index. Results: Reliable measurements of LS values were obtained in 114 patients (92.7%, 114/123). LS values obtained from 2D-SWE with the propagation map positively correlated with the progression of liver fibrosis reported from histopathology (p < 0.001). According to the multivariate linear regression analysis, fibrosis stage was the only factor significantly associated with LS (p < 0.001). The area under the ROC curve of LS from 2D-SWE with the propagation map was 0.773, 0.865, 0.946, and 0.950 for detecting F ≥ 1, F ≥ 2, F ≥ 3, and F = 4, respectively. The optimal cut-off LS values were 5.4, 7.8, 9.4, and 12.2 kPa for F ≥ 1, F ≥ 2, F ≥ 3, and F = 4, respectively. The corresponding sensitivity and specificity of the LS value for detecting cirrhosis were 90.9% and 88.4%, respectively. Conclusion: The LS value obtained from 2D-SWE with a propagation map provides excellent diagnostic performance in evaluating liver fibrosis stage, determined by histopathology.

• The korean journal of orthodontics
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• v.54 no.2
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• pp.79-88
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• 2024

Objective: Alveolar bone loss is a common adverse effect of intrusion treatment. Mandibular incisors are prone to dehiscence and fenestrations as they suffer from thinner alveolar bone thickness. Methods: Thirty skeletal class II patients treated with mandibular intrusion arch therapy were included in this study. Lateral cephalograms and cone-beam computed tomography images were taken before treatment (T1) and immediately after intrusion arch removal (T2) to evaluate the tooth displacement and the alveolar bone changes. Pearson's and Spearman's correlation was used to identify risk factors of alveolar bone loss during the intrusion treatment. Results: Deep overbite was successfully corrected (P < 0.05), accompanied by mandibular incisor proclination (P < 0.05). There were no statistically significant change in the true incisor intrusion (P > 0.05). The labial and lingual vertical alveolar bone levels showed a significant decrease (P < 0.05). The alveolar bone is thinning in the labial crestal area and lingual apical area (P < 0.05); accompanied by thickening in the labial apical area (P < 0.05). Proclined incisors, non-extraction treatment, and increased A point-nasion-B point (ANB) degree were positively correlated with alveolar bone loss. Conclusions: While the mandibular intrusion arch effectively corrected the deep overbite, it did cause some unwanted incisor labial tipping/flaring. During the intrusion treatment, the alveolar bone underwent corresponding changes, which was thinning in the labial crestal area and thickening in the labial apical area vice versa. And increased axis change of incisors, non-extraction treatment, and increased ANB were identified as risk factors for alveolar bone loss in patients with mandibular intrusion therapy.