• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.374-383
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• 2021

In 2020, the diversity of benthic macroinvertebrate communities was investigated in the Sohan stream, an ecological and landscape conservation area, and the results were compared with the previous research conducted in 2011. In total, 42 species (two phyla, three classes, and seven orders) were found in the Sohan stream. Species richness and abundance sharply decreased at all sampling sites because of Typhoons Haishen and Maysak in 2020, which had a direct impact on the stream. In the functional feeding group, the ratio of collector-gatherers was the highest at all sampling sites. However, during the autumn season, the shredder ratio increased from 13.4% to 42.4% in the uppermost stream site. Compared with the diversity of benthic macroinvertebrates surveyed in 2011, a total of 53 species (two phyla, three classes, and eight orders) were found. The percentage of species richness and abundance of Ephemeroptera, Plecoptera, and Trichoptera was more than 50% both in 2011 and 2020. Only the richness of Ephemeroptera was significantly different between them (2011: 2.9 and 2020: 6.7). In this study, the abrupt changes of species richness and abundance in benthic macroinvertebrate were not observed before and after the designation of an ecological and landscape conservation area. However, it is necessary to monitor benthic macroinvertebrates in order to confirm that biodiversity is continuously maintained long after the designation of the ecological and landscape conservation area.

• Journal of Ecology and Environment
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• v.46 no.4
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• pp.316-323
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• 2022

Background: We developed a habitat suitability index (HSI) model for Pedicularis hallaisanensis, a Grade II Endangered Species in South Korea. To determine the habitat variables, we conducted a literature review on P. hallaisanensis with a specific focus on the associated spatial factors, climate, topography, threats, and soil factors to derive five environmental factors that influence P. hallaisanensis habitats. The specific variables were defined based on the collected data and consultations with experts in the field, with the validity of each variable tested through field studies. Results: Mt. Seorak had a suitable habitat area of 2.48 km² for sites with a score of 1 (0.62% of total area) and 0.01 km² for sites with a score of 0.9. Mt. Bangtae had a suitable habitat area of 0.03 km² for sites with a score of 1 (0.02% of total area) and 0 km² for sites with a score of 0.9. Mt. Gaya showed 0.13 km² of suitable habitat for sites with a score of 1 (0.17% of total area) and 0 km² for sites with a score of 0.9. Lastly, Mt. Halla showed 3.12 km² of suitable habitat related to sites with a score of 1 (2.04% of total area) and 4.08 km² of sites with a score of 0.9 (2.66% of total area). Mt. Halla accounts for 73.1% of the total core habitat area. Considering the climatic, soil, and forest conditions together with standardized collection sites, our results indicate that Mt. Halla should be viewed as a core habitat of P. hallaisanensis. Conclusions: The findings in this study provide useful data for the identification of core habitat areas and potential alternative habitats to prevent the extinction of the endangered species, P. hallaisanensis. Furthermore, the developed HSI model allows for the prediction of suitable habitats based on the ecological niche of a given species to identify its unique distribution and causal factors.

• Journal of Korea Water Resources Association
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• v.55 no.8
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• pp.577-588
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• 2022

This study aims to identify the limiting nutrient for algal growth in the Geum River and the significant pollutant sources from the tributaries affecting the water quality and to provide a management alternative for an improvement of water quality. An eight-year of daily data (2013~2020) were collected from the Water Environment Information System (water.nier.go.kr) and Water Resources Management Information System (wamis.go.kr). 14 water quality variables were analyzed at five water quality monitoring stations in the Geum River (WQ1-WQ5). In the Geum River, the water quality variables, especially Chl-a vary greatly in downstream of the river. In the open weir gate operation, TP (total phosphorus) and water temperature greatly influence the growth of algae in downstream of the river. A correlation analysis was used to identify the relationship between variables and investigate the factor affecting algal growth in the Geum River. At the downstream station (WQ5), TP and Temp have shown a strong correlation with Chl-a, indicating they significantly influence the algal bloom. The principal component analysis (PCA) was applied to identify and prioritize the major pollutant sources of the two major tributaries of the river, Gab-cheon and Miho-cheon. PCA identifies three major pollutant sources for Gab-cheon and Miho-cheon, respectively. For Gab-cheon, wastewater treatment plant, urban, and agricultural pollutions pollution are identified as significant pollutant sources. For Miho-cheon, agricultural, urban, and forest land are identified as major pollutant sources. PCA seems to be effective in identifying water pollutant sources for the Geum River and its tributaries in detail and thus can be used to develop water quality management strategies.

• KNOM Review
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• v.23 no.2
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• pp.18-28
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• 2020

With the development of the virtual community, the benefits that IT technology provides to people in fields such as healthcare, industry, communication, and culture are increasing, and the quality of life is also improving. Accordingly, there are various malicious attacks targeting the developed network environment. Firewalls and intrusion detection systems exist to detect these attacks in advance, but there is a limit to detecting malicious attacks that are evolving day by day. In order to solve this problem, intrusion detection research using machine learning is being actively conducted, but false positives and false negatives are occurring due to imbalance of the learning dataset. In this paper, a Random Oversampling method is used to solve the unbalance problem of the UNSW-NB15 dataset used for network intrusion detection. And through experiments, we compared and analyzed the accuracy, precision, recall, F1-score, training and prediction time, and hardware resource consumption of the models. Based on this study using the Random Oversampling method, we develop a more efficient network intrusion detection model study using other methods and high-performance models that can solve the unbalanced data problem.

• Economic and Environmental Geology
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• v.55 no.4
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• pp.353-366
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• 2022

Spatial estimation of geoscience data (geo-data) is challenging due to spatial heterogeneity, data scarcity, and high dimensionality. A novel spatial estimation method is needed to consider the characteristics of geo-data. In this study, we proposed the application of Gaussian Mixture Model (GMM) among machine learning algorithms with multivariate data for robust spatial predictions. The performance of the proposed approach was tested through soil chemical concentration data from a former smelting area. The concentrations of As and Pb determined by ex-situ ICP-AES were the primary variables to be interpolated, while the other metal concentrations by ICP-AES and all data determined by in-situ portable X-ray fluorescence (PXRF) were used as auxiliary variables in GMM and ordinary cokriging (OCK). Among the multidimensional auxiliary variables, important variables were selected using a variable selection method based on the random forest. The results of GMM with important multivariate auxiliary data decreased the root mean-squared error (RMSE) down to 0.11 for As and 0.33 for Pb and increased the correlations (r) up to 0.31 for As and 0.46 for Pb compared to those from ordinary kriging and OCK using univariate or bivariate data. The use of GMM improved the performance of spatial interpretation of anthropogenic metals in soil. The multivariate spatial approach can be applied to understand complex and heterogeneous geological and geochemical features.

• Journal of Life Science
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• v.33 no.2
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• pp.115-128
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• 2023

The fruit of Vaccinum oldhami was separated and purified to obtain the compounds chlorogenic acid (CA), quercetin (QT), and quercitrin (QR). The electron-donating abilities of CA, QT, and QR at 1,000 ㎍/ml were 91.9%, 89.9%, and 77.4%, respectively QT and QR showed 99.5% and 91.4% ABTS⁺ radical scavenging ability at a 1,000 ㎍/ml concentration, respectively, and CA showed a 95% ability or higher at 100 ㎍/ml. Regarding tyrosinase inhibitory activity, CA, QT, and QR exhibited 29.5%, 34.7%, and 23.7% efficacy, respectively, at 1,000 ㎍/ml. Regarding the cell viability for melanoma cells (B16F10) assessed through MTT assay, CA, QT, and QR showed cell a viability of 80% or more at 100 ㎍/ml. To measure the deterrent of protein expression, CA affected TRP-1 and TRP-2 in accordance with increases in concentration. The protein expression inhibition rate of QT was excellent for TRP-1, TRP-2, and tyrosinase. CA was confirmed to have an excellent mRNA expression inhibitory effect against MITF, and the amount of mRNA expression of TRP-1, TRP-2, and tyrosinase decreased with an increase in the CA concentration. As the concentration of QT increased, the mRNA expression of MITF, TRP-2, and tyrosinase decreased. QR decreased the amount of mRNA as the QR concentration increased. The excellent antioxidant and whitening effects of CA, QT, and QR were thus confirmed.

• Journal of Wetlands Research
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• v.25 no.3
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• pp.196-204
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• 2023

Eleutherococcus gracilistylus is a designated rare plant by the Korea Forest Service, a deciduous broad leaf shrub native to the Gotjawal region, Jejudo. This study aimed to analyze the growth responses of E. gracilistylus to three environment factors such as light, moisture, and organic matter, and measure its ecological niche breadth. Based on these results, an attempt was made to identify suitable environmental conditions. E. gracilistylus exhibited increased above-ground length, leaf area, and plant leaf weight under intermediate conditions of light availability(L3, 50% of natural light), rather than very high or very low light conditions. Moisture availability and organic matter availability showed variations in growth responses in terms of leaf count and plant leaf weight. Under moisture availability, growth was favorable under or below intermediate conditions (M3, 240ml), while under organic matter availability, growth response was better above intermediate conditions (N3, 12%). Ecological niche breadth showed in the light factor(0.951), the moisture factor(0.977), and the organic matter content one(0.964). These results indicate that the preferred habitat of E. gracilistylus is somewhat shady, slightly dry, and has a lot of nutrients, and that the environmental factor that has the greatest impact on growth is the amount of light, which is considered to be a priority consideration for habitat management in its native area.

• Journal of Life Science
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• v.32 no.3
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• pp.222-231
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• 2022

This study aimed to confirm the possibility of being used as a cosmetic material material through the verification of the whitening and anti-inflammatory activities of an ethyl acetate fraction from Glechoma hederacea var. longituba (GHEA). The observed electron donating and ABTS⁺ radical scavenging abilities of GHEA were 89.6% and 88.7%, respectively, at 1,000 ㎍/ml concentration, with a tyrosinase inhibitory effect of 22.3% at the same concentration. For cell viability, a rate of 80% or more was observed in all concentrations that treated GHEA on melanoma and macrophage cells. Protein and mRNA expression inhibition was measured by Western blot and RT-PCR for 25, 50, and 100 ㎍/ ml concentrations, and it was confirmed that expression decreases in a concentration-dependent manner as GHEA concentration increases. The inhibition of the whitening-related factors MITF and TRP-2 were superior following GHEA treatment than those of the control group treated with kojic acid of 100 ㎍/ml concentration. For tyrosinase, the lowest mRNA expression rate was 29.1% at 100 ㎍/ml which confirmed excellent inhibition. In analyzing the effects of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α on protein and mRNA expression, IL-6 and TNF-α showed high protein and mRNA inhibition compared to a vitamin C control group. Based on these experimental results, GHEA could be applied as a natural cosmetic material.

• Journal of Korean Society of Rural Planning
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• v.28 no.1
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• pp.1-15
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• 2022

A Care farm is known to have positive effects on various people in psychological, physical, and social aspects. However, care farm services for the disabled, transportation disadvantaged, and socially disadvantaged are limited. This study conducted a demand survey in order to provide basic data for development of the Agro-Healing Virtual Reality Therapy(AVRT) system. The respondents were the ordinary person(n=127) and the disabled person(n=72), and the survey items consisted of 4 categories and 20 items, including intention to use AVRT, requirements for use, factors to be considered when developing the system, and content and program preferences. The intention to use a AVRT was found to be at a high level of 80% or more by respondent characteristics. In addition, similar results were shown in all items such as virtual reality experience, willingness to use, appropriate use time, and willingness to pay by respondent characteristics, and correlation by item was determined through correlation analysis. As for the conditions of use, both sides preferred rural types and were found to have the purpose of healing. However, there were concerns about dizziness in common between system use, and in the case of the disabled person, there were difficulties in purchasing expensive equipment. In the development of the AVRT system, the part of sensory priority, important technology level, and color preference were evaluated, and the preference of content and programs to be developed in the system was identified. Fruit, vegetables, flowers, and animals preferred mandarin, tomato, tulips, and dogs first, horticultural healing preferred harvest management for the ordinary person, plant cultivation for the disabled person, and forest healing and animal education preferred walking and dog-related programs. However, agricultural work was found to be a program with high preference for making processed foods for the ordinary person and creating an animal breeding environment for the disabled person. The result of this study is expected to provide reference data that can be suggested for the development of Agro-healing Virtual Reality Therapy system.

• Korean Journal of Plant Resources
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• v.36 no.4
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• pp.341-368
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• 2023

Distribution of plant resources in Mt. Baekseok located at Pyeongchang-gun, Gangwon-do, were surveyed for a total 17 times from April 2021 to September 2022. The result of this survey revealed 628 taxa, consisting of 99 families, 346 genera, 552 species, 20 subspecies, 49 varieties, 6 forms, and one hybrid. Among them, 21 taxa were endemic plants to Korea, 12 taxa were red list plants by the Ministry of Environment and 560 taxa were red list plants by the Korea Forest Service. The floristic target species amounted to 164 taxa, specifically one taxon of grade V, 20 taxa of grade IV, 52 taxa of grade III, 53 taxa of grade II, and 38 taxa of grade I. In addition, 34 taxa were classified as plants adaptable to climate change. 42 taxa of alien plants and 3 taxa of ecosystem disturbance species were also found in this area. Useful plants listed consists of 246 taxa (39.2%) of edible plants, 215 taxa (34.2%) of pasture plants, 187 taxa (29.8%) of medicinal plants, 75 taxa (11.9%) of ornamental plants and 22 taxa (3.5%) of timber plants, respectively.