• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.98-104
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• 2018

Oxyresveratrol (trans-2, 3', 4, 5'-tetrahydroxystilbene), found in many plants including grape, peanut and mulberry, is a phytoalexin, an antimicrobial and antioxidative substance that rapidly accumulates in areas infected by the pathogen. We examined the accumulation of oxyresveratrol in nine Morus alba L. cultivars with respect to storage time and temperature postharvest and infection with GRAS microorganisms. Among the nine cultivars, the Suwon cultivar showed the highest oxyresveratrol content (9.6-fold increase) postharvest, when stored at $30^{\circ}C$ for 7 days. The optimal temperature and postharvest storage time for oxyresveratrol accumulation was $30^{\circ}C$ and 6 days. When Ramulus mori was infected with five microorganisms, the accumulation of oxyresveratrol increased over 4-fold in response to B. coagulans infection. These results suggest that oxyresveratrol accumulation is influenced by storage temperature, storage time, Ramulus mori cultivars, and microbial attack. Therefore, postharvest storage for an appropriate time period at a suitable temperature might be a useful way to industrially produce Ramulus mori cultivars with high oxyresveratrol content.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.169-193
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• 2016

In order to characterize the Neotectonic crustal deformation and current stress field in and around the Korean Peninsula and to interpret their tectonic implications, this paper synthetically analyzes the previous Quaternary fault and focal mechanism solution data and recent geotechnical in-situ stress data and examines the characteristics of crustal deformations and tectonic settings in and around East Asia after the Miocene. Most of the Quaternary fault outcrops in SE Korea occur along major inherited fault zones and show a NS-striking top-to-the-west thrust geometry, indicating that the faults were produced by local reactivation of appropriately oriented preexisting weaknesses under EW-trending pure compressional stress field. The focal mechanism solutions in and around the Korean Peninsula disclose that strike-slip faulting containing some reverse-slip component and reverse-slip faulting are significantly dominant on land and in sea area, respectively. The P-axes are horizontally clustered in ENE-WSW direction, whereas the T-axes are girdle-distributed in NNW direction. The geotechnical in-situ stress data in South Korea also indicate the ENE-trending maximum horizontal stress. The current crustal deformation in the Korean Peninsula is thus characterized by crustal contraction under regional ENE-WSW or E-W compression stress field. Based on the regional stress trajectories in and around East Asia, the current stress regime is interpreted to have resulted from the cooperation of westward shallow subduction of the Pacific Plate and collision of Indian and Eurasian continents, whereas the Philippine Sea plate have not a decisive effect on the stress-regime in the Korean Peninsula due to its high-angle subduction that resulted in dominant crust extension of the back-arc region. It is also interpreted that the Neotectonic crustal deformation and present-day tectonic setting of East Asia commenced with the change of the Pacific Plate motion during 5~3.2 Ma.

• Korean Journal of Construction Engineering and Management
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• v.20 no.4
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• pp.114-125
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• 2019

Off-Site Construction (OSC) is a new construction method based on factory production. OSC (Off-Site Construction) is a new construction method based on factory production. Researches such as OSC-related design and production standardization, transport methods are actively conducted in the U.S., UK and other parts of the world as this new method has an edge over existing methods in terms of productivity, economy and quality. As the emergence of this new area requires reasonable management, an analysis of the scope of construction project management is required accordingly. Therefore, this research analyzed the study trends and relationships at the CM/PM range's "Operation level" to identify areas of study, relationship between studies and deficiencies in current research. This study carried out a comprehensive literature review of the OSC (CM/PM) research by analyzing 94 papers in Operation level as of September 3, 2018, and the analysis results are as follows. (1) Working stage level researches have been increasing rapidly since 2006. (2) Non-volumetric type is contributing most significantly at work stage level. In the building sector, it has been identified that problems such as residential: living, quality issues, non-residential: economic difficulties, factory: productivity problems have been addressed. (4) The Non-volumetric pre-assembly type dealt with the economic feasibility of residential and non-residential buildings, whereas the modular type was studied in regards to assembly quality. (5) From 2006, project management areas (e.g., quality, human resources, risks) have been expanded. It is expected that this research will help find new areas of research for OSC. If the analysis is carried out to the level of the industrial, corporate and project phases in the future, it is deemed that the overall research flow and area of the OSC industry can be identified.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.565-573
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• 2022

Gingival inflammation is one of the main causes that can be related to various periodontal diseases. Human gingival fibroblast (HGF) is the major constituent in periodontal connective tissue and secretes various inflammatory mediators, such as nitric oxide (NO) and prostaglandin E₂ (PGE₂), upon lipopolysaccharide stimulation. This study is aimed at investigating the anti-inflammatory and antioxidative activities of Lotus Root extract (LRE) in Porphyromonas gingivalis derived lipopolysaccharide (LPS-PG)-stimulated HGF-1 cells. The concentration of NO and PGE₂, as well as their responsible enzymes, inducible NO synthase (iNOS), and cyclooxygenase-2 (COX-2), was analyzed by Griess reaction, ELISA, and western blot analysis. LPS-PG sharply elevated the production and protein expression of inflammatory mediators, which were significantly attenuated by LRE treatment in a dose-dependent manner. LRE treatment also suppressed activation of Toll-like receptor 4 (TLR4)/myeloid differentiation primary response gene 88 (MyD88) and nuclear factor-κB (NF-κB) in LPS-PG-stimulated HGF-1 cells. In addition, one of phase II enzyme, NAD(P)H quinone dehydrogenase (NQO)-1, and its transcription factor, Nuclear factor erythroid 2-related factor 2 (Nrf2), were significantly induced by LRE treatment. Consequently, these results suggest that LRE ameliorates LPS-PG-induced inflammatory responses by attenuating TLR4/MyD88-mediated NF-κB, and activating NQO-1/Nrf2 antioxidant response element signaling pathways in HGF-1 cells.

• Pediatric Infection and Vaccine
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• v.30 no.2
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• pp.84-90
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• 2023

Purpose: Infants aged ≤90 days with fever are susceptible to severe infections. This study aimed to analyze the clinical features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in this particular age group. Methods: Infants aged ≤90 days who were diagnosed with coronavirus disease 2019 (COVID-19) and hospitalized between March 1, 2020, and May 1, 2022 were included. Medical records of patients were retrospectively reviewed. Results: A total of 105 infants with COVID-19 were included; 27 (25.7%) neonates aged <28 days, and 48 (45.7%) and 30 (28.6%) infants aged 28-59 days and 60-90 days, respectively. Five (4.7%) patients remained asymptomatic and 68 (62.8%) were febrile, with a median fever duration of 2 days. The most common symptoms were respiratory including cough (66.6%), nasal stuffiness (51.4%), and rhinorrhea (40.9%). Blood cultures were performed in 10 infants but no organisms were detected. Cultures of bag-collected urine specimens from 8 infants were grown, resulting in positive growth for 2 without pyuria. Nine (8.6%) infants were treated with empirical antibiotics for a median duration of 2.3 days (range, 1-7 days). All 105 infants showed improvement without any complications, and there were no fatal cases. Conclusions: In this study, most infants aged ≤90 days with COVID-19 presented with mild symptoms and none of those evaluated had documented bacterial co-infection. The favorable prognosis among young infants with SARS-CoV-2 may aid clinicians in tailoring their approach to evaluation and management during outbreaks.

• Korean Journal of Communication Studies
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• v.22 no.2
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• pp.89-121
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• 2014

In order to suggest a strategy for continuous growth of webtoon, this article examined webtoon usage motivation and tried to make a prediction about culture content products and services connected with webtoon, including intention for viewing movies, based on webtoon; intention for switching to paid webtoon content, and intention for buying webtoon character products. From the point of view of Uses and Gratification Theory intentions for using webtoon and human sociocultural behavior intention are already predicted but with the usefulness of Theory of Planned Behavior Integrated Model this study extended the explanation power of prediction about webtoon related behavioral intention. Results found 5 motivational factors for webtoon usage i.e. 'seeking information', 'entertainment and access availability', 'webtoon genre characteristics', 'influence from a friend or acquaintance', and 'escapism and tension release'. Among them the ones that influenced the intention for viewing movies, based on webtoon, were found to be 'webtoon genre characteristics', 'escapism and tension release' and the 3 variables from Theory of Planned Behavior. 'Seeking information', 'entertainment and access availability', 'webtoon genre characteristics', and all the 3 variables from Theory of Planned Behavior were found to influence the intention for switching to paid webtoon content. The intention for buying webtoon based character products was affected by the motivational factors 'seeking information', 'escapism and tension release' and the behavior and subjective norms variables from Theory of Planned Behavior. Based on the uncommon results from the research several suggestions were made for the continuous growth of webtoon.

• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.979-995
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• 2023

As wildfires are difficult to predict, real-time monitoring is crucial for a timely response. Geostationary satellite images are very useful for active fire detection because they can monitor a vast area with high temporal resolution (e.g., 2 min). Existing satellite-based active fire detection algorithms detect thermal outliers using threshold values based on the statistical analysis of brightness temperature. However, the difficulty in establishing suitable thresholds for such threshold-based methods hinders their ability to detect fires with low intensity and achieve generalized performance. In light of these challenges, machine learning has emerged as a potential-solution. Until now, relatively simple techniques such as random forest, Vanilla convolutional neural network (CNN), and U-net have been applied for active fire detection. Therefore, this study proposed an active fire detection algorithm using state-of-the-art (SOTA) deep learning techniques using data from the Advanced Himawari Imager and evaluated it over East Asia and Australia. The SOTA model was developed by applying EfficientNet and lion optimizer, and the results were compared with the model using the Vanilla CNN structure. EfficientNet outperformed CNN with F1-scores of 0.88 and 0.83 in East Asia and Australia, respectively. The performance was better after using weighted loss, equal sampling, and image augmentation techniques to fix data imbalance issues compared to before the techniques were used, resulting in F1-scores of 0.92 in East Asia and 0.84 in Australia. It is anticipated that timely responses facilitated by the SOTA deep learning-based approach for active fire detection will effectively mitigate the damage caused by wildfires.

• Journal of Food Hygiene and Safety
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• v.39 no.1
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• pp.35-43
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• 2024

Numerous methods have been applied to assess the antibacterial effectiveness of hand hygiene products. However, the different results obtained through various evaluation methods have complicated our understanding of the real efficacy of the products. Few studies have compared test methods for assessing the efficacy of hand hygiene products. In particular, reports on ex vivo pig skin testing are limited. This study aimed to compare and characterize the methodologies applied for evaluating hand hygiene products, involving in vitro, ex vivo, and in vivo approaches, applicable to both leave-on sanitizers and wash-off products. Our further aim was to enhance the reliability of ex vivo test protocols by identifying influential factors. We performed an in vitro method (EN1276) and an in vivo test (EN1499 and ASTM2755) with at least 20 participants, against Serratia marcescens or Escherichia coli and Staphylococcus aureus. For the ex vivo experiment, we used pig skin squares prepared in the same way as those used in the in vivo test method and determined the optimal treated sample volumes for sanitizers and the amount of water required to wash off the product. The hand sanitizers showed at least a 5-log reduction in bacterial load in the in vitro test, while they showed little antibacterial activity in the in vivo and ex vivo tests, particularly those with a low alcohol content. For the hand wash products, the in vitro test was limited because of bubble formation or the high viscosity of the products and it showed low antibacterial activity of less than a 1-log reduction against E. coli. In contrast, significantly higher log reductions were observed in ex vivo and in vivo tests, consistently demonstrating these results across the two methods. Our findings revealed that the ex vivo and in vivo tests reflect the two different antibacterial mechanisms of leave-on and wash-off products. Our proposed optimized ex vivo test was more rapid and more precise than the in vitro test to evaluate antibacterial results.

• Communications of Mathematical Education
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• v.38 no.2
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• pp.167-186
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• 2024

Since the 5th mathematics curriculum, the goals of mathematics education have been presented in three categories: cognitive, process, and affective goals. In the 2022 revised mathematics curriculum, the content system was also presented as knowledge-understanding, process-skill, and value-attitude. Therefore, in order to present lesson goals to students, it is necessary to present all three aspects that are the goals of mathematics education. Currently, the lesson titles presented in mathematics textbooks are directly linked to lesson goals and are the first source of information for students during class. Accordingly, this study analyzed how the three categories of lesson titles and content system presented in the 2015 revised 1st and 2nd grade mathematics textbook are connected. As a result, most lesson titles presented two of the three categories, but the reflected elements showed a tendency to focus on the categories of knowledge-understanding and process-skill. Some cases of lesson titles reflected content elements of the value-attitude category, but this showed significant differences depending on the mathematics content area. Considering the goals of mathematics lessons, it will be necessary to look at ways to present lesson titles that reflect the content elements of the value-attitude categories and also explore ways to present them in a balanced way. In particular, considering the fact that students can accurately understand the goals of the knowledge-understanding categories even without presenting them, descriptions that specifically reflect the content elements of the process-skill and value-attitude categories seem necessary. Through this, we attempted to suggest the method of presenting the lesson titles needed when developing the 2022 revised mathematics textbook and help present effective lesson goals using this.

• Journal of Korean Academy of Nursing
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• v.11 no.2
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• pp.105-123
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• 1981

This study was carried out during the month of September 1976 to analyse and compare the health complaints of two groups of the university women, those who lived at home and those who lived in the university dormitory. The purpose of the study was to provide basic data required by the university health program for planning related to the health need of women students. The study sample consisted of 434 students living in the dormitory and 381 students living at home enrolled for the fall semester 1976 in a womens university in Seoul. The instrument used for the collection of data was an abridged version of a modified Cornell Medical Index. The questionarre included 35 items related to physical health complaint and 22 items related to mental health complaints. The data was treated by a computer (SPSS) using one way analysis, the Fishers' ratio and Chi-Square test at the 5％ level were used for the test for statistical significance. The interpretation of this study is limited due to the sample which was restricted to one university and not randomly selected. To guide the direction of the study, it was hypothesized that the rate of expressed health problems of students living in the dormitory would be Venter than that of students living at home. The hypothesis was tested and rejected. The following is a summary of the findings; 1. Total health (physical and mental) complaints a. There was no statistically significant difference between the home and dormitory groups with regard to total health complaints expressed. b. The rate of total complaints expressed by the home group significantly higher than dormitory group only among third year students. c. There was no statistically significant between the home and dormitory groups in their satisfaction with their economic situation. d. The home group showed a significantly higher rate of complaints related to the Nervous System compared to that of the dormitory group. 2. Physical health complaints a. Students living at home showed a significantly higher rate of physical complaints than the dormitory group. b. When the year variable was controlled, the third year was the only group which showed a different rate between home and dormitory groups; the home group presented a higher rate. c. Since the year variable seemed to affect the physical complaints those data were further analysed to see whether the specific system areas were operating as variables in each year. The results were as follow: Among the home group, First year students showed a higher rate in Family History of Disease, while the third year students more Nervous System and Cardiovascular System complaints. Among the dormitory group, only fourth year students showed a higher rate in the Skeletal-Muscular System. This was the only area the dormitory group though only for the fourth year students supported the hypothesis. d. When the economic satisfaction variable was controlled, the satisfied group was the only group which showed a different rate between home and dormitory groups; the home group presented higher rate. e. Since the economic satisfaction variable seemed to affect the physical complaints those data were further analyzed to see whether the specific system areas were operating as variables in each economic satisfaction level, but there was no statistically significant difference between home and dormitory groups. 3. Mental health complaints a. There was no significantly difference between home and dormitory groups with regard to mental health complaints expressed. b. When the year variable was controlled the third year group was the only group which showed a different rate between home and dormitory groups; the home group presented a higher rate. c. Since the year variable seemed to affect the mental complaints, those data were further analyzed to see whether the specific system areas were operatings variables in each economic satisfaction level. The result were as follows: Among the home group, the third year students showed higher rates in Inadequacy and Anxiety. d. When the economic satisfaction variable was controlled, the very satisfied group was the only group which showed a different rate between home and dormitory groups: the home group presented a higher rate. Since the economic satisfaction variable seemed to affect the mental complaints, those data were further analysed to see whether the specific system areas were operating as variables in each economic satisfaction level, but there was no statistical significant difference between the home and dormitory groups. Although the social environment of dormitory life differs from family life, there was no difference in the rate of total health problem complaints between the home and dormitory groups but the home group showed a higher rate of physical health complaints than the dormitory group. Possible positive factors influencing dormitory life and negative factors influencing family life affecting health complaints must be explored in order to relate to the health needs of the university health program. This study could not define the causes for the fewer physical complaints of dormitory students living at home. Further study of such causal factors recommended in order to provide the data needed to contribute to a more effective health program.