• Title/Summary/Keyword: frequency change

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Spatial Distribution of Macrobenthic Communities on the Rocky Intertidal Zone of Specified Islands, Southern Coast of Korea (남해안 특정도서 암반조간대의 대형저서동물 군집의 공간분포)

  • Yang, Sehee;Yang, Hyosik;Lee, Changil;Seo, Chonghyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.853-865
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    • 2022
  • In this study, from August to October 2019, we conducted a survey of the spatial distribution and dominant species of macrobenthos on the rocky intertidal zones of 38 specified islands distributed along the southern coast of Korea. On the basis of observation made using 50 × 50 cm quadrats, we identified a total of 80 species, among which, Mollusca were the most abundant fauna, with 54 species that accounted for 67.4% of the total, followed by Crustacea with 15 species (18.7%). The recorded numbers of Cnidaria, Porifera, and Echinodermata species ranged from 1 to 6. In terms of the regional patterns of species richness, specified islands in Yeosu were found to be the most species rich, supporting 61 species, whereas islands in Hadong, Namhae, and Chujado were found to have a similar level of species richness, ranging from 42 to 46 species. Islands in Boseong and Goheung were home to the fewest species, with only 29 species being recorded. At the sampling station scale, we noted a considerable difference in faunal richness, ranging from 6 (St. 6) to 33 (St. 20) species. Among the recorded species, Echinolittorina radiata was identified as the dominant species on 15 specified islands, with the next most abundant species being Tetraclita japonica, considered an indicator species of climate change, which was recorded on 11 islands. In terms of frequency, E. radiata, found on 36 islands, was identified as the most frequently occurring species, followed by Reishia clavigera (30 islands), Mytilisepta virgata (29), Nerita japonica (28), Ligia. exotica (27), and Littorina brevicula (26). Of the 80 species identified, 9, 4, and 2 species of Mollusca, Crustacea, and Cnidaria, respectively, are classified as Marine fauna of accepted foreign export, whereas 50 are Red List species, 44 are species of Least Concern, 3 are Data Deficient species, and 1 species was not evaluated. However, during the survey, we found no Near Threatened or Not Applicable species. On the basis of the findings of this survey, it would appear that the abundance and richness of macrobenthic fauna inhabiting the rocky intertidal zones of specified islands along the southern coast of Korea differ according to different habitat conditions, particularly with respect to the duration of exposure and the extent and properties of the substrata. The findings of this study will provide baseline data for future monitoring and management of specified islands in Korea.

A study on the derivation and evaluation of flow duration curve (FDC) using deep learning with a long short-term memory (LSTM) networks and soil water assessment tool (SWAT) (LSTM Networks 딥러닝 기법과 SWAT을 이용한 유량지속곡선 도출 및 평가)

  • Choi, Jung-Ryel;An, Sung-Wook;Choi, Jin-Young;Kim, Byung-Sik
    • Journal of Korea Water Resources Association
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    • v.54 no.spc1
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    • pp.1107-1118
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    • 2021
  • Climate change brought on by global warming increased the frequency of flood and drought on the Korean Peninsula, along with the casualties and physical damage resulting therefrom. Preparation and response to these water disasters requires national-level planning for water resource management. In addition, watershed-level management of water resources requires flow duration curves (FDC) derived from continuous data based on long-term observations. Traditionally, in water resource studies, physical rainfall-runoff models are widely used to generate duration curves. However, a number of recent studies explored the use of data-based deep learning techniques for runoff prediction. Physical models produce hydraulically and hydrologically reliable results. However, these models require a high level of understanding and may also take longer to operate. On the other hand, data-based deep-learning techniques offer the benefit if less input data requirement and shorter operation time. However, the relationship between input and output data is processed in a black box, making it impossible to consider hydraulic and hydrological characteristics. This study chose one from each category. For the physical model, this study calculated long-term data without missing data using parameter calibration of the Soil Water Assessment Tool (SWAT), a physical model tested for its applicability in Korea and other countries. The data was used as training data for the Long Short-Term Memory (LSTM) data-based deep learning technique. An anlysis of the time-series data fond that, during the calibration period (2017-18), the Nash-Sutcliffe Efficiency (NSE) and the determinanation coefficient for fit comparison were high at 0.04 and 0.03, respectively, indicating that the SWAT results are superior to the LSTM results. In addition, the annual time-series data from the models were sorted in the descending order, and the resulting flow duration curves were compared with the duration curves based on the observed flow, and the NSE for the SWAT and the LSTM models were 0.95 and 0.91, respectively, and the determination coefficients were 0.96 and 0.92, respectively. The findings indicate that both models yield good performance. Even though the LSTM requires improved simulation accuracy in the low flow sections, the LSTM appears to be widely applicable to calculating flow duration curves for large basins that require longer time for model development and operation due to vast data input, and non-measured basins with insufficient input data.

A Study on Industry-specific Sustainability Strategy: Analyzing ESG Reports and News Articles (산업별 지속가능경영 전략 고찰: ESG 보고서와 뉴스 기사를 중심으로)

  • WonHee Kim;YoungOk Kwon
    • Journal of Intelligence and Information Systems
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    • v.29 no.3
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    • pp.287-316
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    • 2023
  • As global energy crisis and the COVID-19 pandemic have emerged as social issues, there is a growing demand for companies to move away from profit-centric business models and embrace sustainable management that balances environmental, social, and governance (ESG) factors. ESG activities of companies vary across industries, and industry-specific weights are applied in ESG evaluations. Therefore, it is important to develop strategic management approaches that reflect the characteristics of each industry and the importance of each ESG factor. Additionally, with the stance of strengthened focus on ESG disclosures, specific guidelines are needed to identify and report on sustainable management activities of domestic companies. To understand corporate sustainability strategies, analyzing ESG reports and news articles by industry can help identify strategic characteristics in specific industries. However, each company has its own unique strategies and report structures, making it difficult to grasp detailed trends or action items. In our study, we analyzed ESG reports (2019-2021) and news articles (2019-2022) of six companies in the 'Finance,' 'Manufacturing,' and 'IT' sectors to examine the sustainability strategies of leading domestic ESG companies. Text mining techniques such as keyword frequency analysis and topic modeling were applied to identify industry-specific, ESG element-specific management strategies and issues. The analysis revealed that in the 'Finance' sector, customer-centric management strategies and efforts to promote an inclusive culture within and outside the company were prominent. Strategies addressing climate change, such as carbon neutrality and expanding green finance, were also emphasized. In the 'Manufacturing' sector, the focus was on creating sustainable communities through occupational health and safety issues, sustainable supply chain management, low-carbon technology development, and eco-friendly investments to achieve carbon neutrality. In the 'IT' sector, there was a tendency to focus on technological innovation and digital responsibility to enhance social value through technology. Furthermore, the key issues identified in the ESG factors were as follows: under the 'Environmental' element, issues such as greenhouse gas and carbon emission management, industry-specific eco-friendly activities, and green partnerships were identified. Under the 'Social' element, key issues included social contribution activities through stakeholder engagement, supporting the growth and coexistence of members and partner companies, and enhancing customer value through stable service provision. Under the 'Governance' element, key issues were identified as strengthening board independence through the appointment of outside directors, risk management and communication for sustainable growth, and establishing transparent governance structures. The exploration of the relationship between ESG disclosures in reports and ESG issues in news articles revealed that the sustainability strategies disclosed in reports were aligned with the issues related to ESG disclosed in news articles. However, there was a tendency to strengthen ESG activities for prevention and improvement after negative media coverage that could have a negative impact on corporate image. Additionally, environmental issues were mentioned more frequently in news articles compared to ESG reports, with environmental-related keywords being emphasized in the 'Finance' sector in the reports. Thus, ESG reports and news articles shared some similarities in content due to the sharing of information sources. However, the impact of media coverage influenced the emphasis on specific sustainability strategies, and the extent of mentioning environmental issues varied across documents. Based on our study, the following contributions were derived. From a practical perspective, companies need to consider their characteristics and establish sustainability strategies that align with their capabilities and situations. From an academic perspective, unlike previous studies on ESG strategies, we present a subdivided methodology through analysis considering the industry-specific characteristics of companies.

A Study on Changes of Symptoms and Signs Diagnosised by Differentiation of the Pattern Identification in Acute Ischemic Stroke Patients with Collaborative Treatment (한·양방 병행치료를 시행한급성기 뇌경색 환자에게 변증(辨證)별 평가항목 호전도에 대한 연구)

  • Lu, Hsu-yuan;Kim, Soo-kyung;Shim, So-ra;Kim, Hye-mi;Park, Joo-young;Cho, Seung-yeon;Park, Seong-uk;Jung, Woo-sang;Moon, Sang-kwan;Park, Jung-mi;Ko, Chang-nam;Cho, Ki-ho;Kim, Young-suk;Bae, Hyung-sup
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.12 no.1
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    • pp.16-23
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    • 2011
  • Object : The purpose of this study is to observe the changes of symptoms and signs diagnosised by differentiation of the pattern identification in stroke patients. Methods : Seventy subjects were recruited from patients with stroke within ten days of onset. We chose twenty-nine subjects diagnosised as same differentiation of the pattern identification, and who had at least on follow up session. We had investigated change of symptoms and signs diagnosised by differentiation of the pattern identification. Results : There were five symptoms and signs (thick fur, dry fur, difficult defecation, heat vexation and aversion to heat, normal pulse) and ten (heavy-headedness, frequency of defecation, hard defecation, feel heavy, slippery pulsem, dry mouth, bitter taste in the mouth, feel lazy, look lazy) symptoms and signs that were statistically significant improved in fire-heat patterns and dampness-phlegm pattern, respectively. Conclusions : This study provides evidence that collaborative treatment is effective in improving some symptoms and signs in acute ischemic stroke patients diagnosised by fire-heat pattern and dampness-phlegm pattern. Further studies with larger scale, longer observation period would be required.

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Analysis of inundation and rainfall-runoff in mountainous small catchment using the MIKE model - Focusing on the Var river in France - (MIKE 모델을 이용한 산지소유역 강우유출 및 침수 분석 - 프랑스 Var river 유역을 중심으로 -)

  • Lee, Suwon;Jang, Dongwoo;Jung, Seungkwon
    • Journal of Korea Water Resources Association
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    • v.56 no.1
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    • pp.53-62
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    • 2023
  • Recently, due to the influence of climate change, the occurrence of damage to heavy rain is increasing around the world, and the frequency of heavy rain with a large amount of rain in a short period of time is also increasing. Heavy rains generate a large amount of outflow in a short time, causing flooding in the downstream part of the mountainous area before joining the small and medium-sized rivers. In order to reduce damage to downstream areas caused by flooding, it is very important to calculate the outflow of mountainous areas due to torrential rains. However, the sewage network flooding analysis, which is currently conducting the most analysis in Korea, uses the time and area method using the existing data rather than calculating the rainfall outflow in the mountainous area, which is difficult to determine that the soil characteristics of the region are accurately applied. Therefore, if the rainfall is analyzed for mountainous areas that can cause flooding in the downstream area in a short period of time due to large outflows, the accuracy of the analysis of flooding characteristics that can occur in the downstream area can be improved and used as data for evacuating residents and calculating the extent of damage. In order to calculate the rainfall outflow in the mountainous area, the rainfall outflow in the mountainous area was calculated using MIKE SHE among the MIKE series, and the flooding analysis in the downstream area was conducted through MIKE 21 FM (Flood model). Through this study, it was possible to confirm the amount of outflow and the time to reach downstream in the event of rainfall in the mountainous area, and the results of this analysis can be used to protect human and material resources through pre-evacuation in the downstream area in the future.

A Study on the Quality of Life of Elderly People with Dementia and the Environmental Factor of Facilities (치매노인의 삶의 질과 시설 환경 요인에 관한 연구)

  • Park, Sejeong;Kim, Hangon
    • 한국노년학
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    • v.29 no.4
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    • pp.1361-1381
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    • 2009
  • There have lately been a variety of social issues in our society due to rapid social changes. Specifically, how to approach elderly people who suffer from dementia is never an easy task, and few in-depth studies have ever focused on their quality of life due to that. The purpose of this study was to examine the quality of life of elderly people with dementia and the relationship between their quality of life and the environments of facilities for them in an attempt to lay the foundation for the development of compatible programs tailored to the environments of the facilities and for relevant policy setting. It's ultimately meant to improve the quality of life of the elderly with dementia and the environments of facilities for them. The subjects in this study were elderly people with dementia who were housed in senior residential and medical welfare facilities in Daegu and Gyeongsangbukdo. The collected data were analyzed with a SPSS 12.0 program, and frequency analysis, cross-tabs and multiple logistic regression analysis were utilized. As a result, facility environments were identified as one of the variables that had a significant impact on the quality of life of the elderly people with dementia. There are some suggestions about how to boost their quality of life: First, good environments should be prepared in consideration of the characteristics of elderly people with dementia in order for themto be satisfied with their own quality of life, and the way of looking at their potentials should be changed. Second, it's found that main caregivers affected the quality of life of the elderly people with dementia, and the kind of programs that focus on the improvement of the relationship between elderly people with dementia and their main caregivers is required. Third, there should be a change in the environments of the facilities. The facilities should be well equipped to successfully respond to the symptoms of elderly people with dementia. To redress their poor accessibility to the facilities, infrastructure involving nursing homes and professional personnels should be built by utilizing the Internet, and the facilities and local community should make concerted efforts to provide quality care to elderly people in want of it.

An Analysis of Fun Distance of Visually Impaired School Physical Education Program (시각장애학교 체육프로그램의 재미거리 분석)

  • Shim, Ji-Hoon;Lee, Seung-Chan;Her, Mun-Young
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.3
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    • pp.181-192
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    • 2019
  • The purpose of this study is to look at the fun that high school students from blind schools feel in sports programs. A questionnaire was used to collect data from 10 out of 12 blind schools nationwide, including 122 male and 102 female students. Research tools are open questionnaires and questions are as follows. - Questionnaire: "Write down three of the most interesting things about sports programs." The data analysis was done with frequency analysis and the following conclusions were drawn. First, male high school students at blind schools are able to build up their physical strength in the area of competent factors (control-self) (23, 21.5%), in the area of competent factors (7, 77.8%) and in the area of motion-related factors (competition) (24, 15.1%), and in the area of non-execution factors (26, 37.7%), Second, high school girls with visual impairments did not respond in the areas of proficiency (control-self) because of stress release (25, 26.6%), in the areas of control-tain), in the areas of movement (competition) because they were able to do various exercises (22, 15.7%), and in the areas of non-watering (environmental) (18, 37.5%). Third, in the sports program comparative analysis of high school students between genders of blind schools, boys are interested in health and physical fitness in the field of competent factors (control-self) and girls are considered to be a means of relieving stress. In the field of competent factors (control-others), boys and girls can react to a variety of sports opportunities. In the future, by studying the fun of students in the physical education program through research to find out more fun in the school physical education program, we will explore practical ways to maximize student participation and increase motivation level The educational aspect of the process, that is, the educational value provided by the physical education, should be composed of content that can change the thinking and behavior of the teacher and the student so that the program contents and operation method.

Detection of Wildfire Burned Areas in California Using Deep Learning and Landsat 8 Images (딥러닝과 Landsat 8 영상을 이용한 캘리포니아 산불 피해지 탐지)

  • Youngmin Seo;Youjeong Youn;Seoyeon Kim;Jonggu Kang;Yemin Jeong;Soyeon Choi;Yungyo Im;Yangwon Lee
    • Korean Journal of Remote Sensing
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    • v.39 no.6_1
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    • pp.1413-1425
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    • 2023
  • The increasing frequency of wildfires due to climate change is causing extreme loss of life and property. They cause loss of vegetation and affect ecosystem changes depending on their intensity and occurrence. Ecosystem changes, in turn, affect wildfire occurrence, causing secondary damage. Thus, accurate estimation of the areas affected by wildfires is fundamental. Satellite remote sensing is used for forest fire detection because it can rapidly acquire topographic and meteorological information about the affected area after forest fires. In addition, deep learning algorithms such as convolutional neural networks (CNN) and transformer models show high performance for more accurate monitoring of fire-burnt regions. To date, the application of deep learning models has been limited, and there is a scarcity of reports providing quantitative performance evaluations for practical field utilization. Hence, this study emphasizes a comparative analysis, exploring performance enhancements achieved through both model selection and data design. This study examined deep learning models for detecting wildfire-damaged areas using Landsat 8 satellite images in California. Also, we conducted a comprehensive comparison and analysis of the detection performance of multiple models, such as U-Net and High-Resolution Network-Object Contextual Representation (HRNet-OCR). Wildfire-related spectral indices such as normalized difference vegetation index (NDVI) and normalized burn ratio (NBR) were used as input channels for the deep learning models to reflect the degree of vegetation cover and surface moisture content. As a result, the mean intersection over union (mIoU) was 0.831 for U-Net and 0.848 for HRNet-OCR, showing high segmentation performance. The inclusion of spectral indices alongside the base wavelength bands resulted in increased metric values for all combinations, affirming that the augmentation of input data with spectral indices contributes to the refinement of pixels. This study can be applied to other satellite images to build a recovery strategy for fire-burnt areas.

Fish Community Characteristics and Distribution Aspect of Four Endangered Species in the Byekgye Stream, Korea (벽계천의 어류군집 특성 및 멸종위기 4종의 서식양상)

  • HyeongSu Kim;Myeong-Hun Ko
    • Korean Journal of Environment and Ecology
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    • v.38 no.1
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    • pp.55-66
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    • 2024
  • This study conducted a survey to investigate the characteristics of fish communities and the inhabiting status of endangered species in the Byekgye Stream, Korea from April to September 2020. A total of 3,415 fish of 9 families and 31 species were collected from 7 survey stations during the survey period. The dominant species was Zacco koreanus (relative abundance of 31.2%), and the subdominant species was Z. platypus (15.0%), followed by Pungtungia herzi (11.7%), Acheilognathus yamatsutae (5.4%), A. lanceolata intermedia (4.8%), Rhinogobius brunneus (4.4%), and Pseudopungtungia tenuicorpa (4.3%). Among the fish species collected, 19 (61.3%) were identified as Korean endemic species, and two cold-water fish species sensitive to climate change (Rhynchocypris kumgangensis and Cottus koreanus) were collected. Four species were designated as class II endangered wildlife by the Ministry of Environment: A. signifer, P. tenuicorpa, Rhodeus pseudosericeus, and C. koreanus. A. signifer and P. tenuicorpa mainly inhabited the mid to lower streams, R. pseudosericeus in the midstream, and R. pseudosericeus in the upstream. P. tenuicorpa inhabited in large numbers, and estimating the age by total length-frequency distribution in July, the total length of the 26-35 mm group was estimated as 0 years old, the 54-75 mm group as 1 year old, 82-97 mm group as 2 years old, 104-109 mm group as 3 years or older. The cluster analysis showed that the dominance index decreased from upstream to downstream, but the diversity, evenness, and richness index increased. The water quality of Byekgye Stream was evaluated as good overall since the river health (fish assessment index, FAI) using fish was evaluated as excellent (5 stations) and good (2 stations). Byekgye Stream has relatively well-preserved habitats, but conservation measures are required as habitats are disturbed by river repair work in some parts of the midstream and downstream areas where many endangered species inhabit.

Validation of ECOSTRESS Based Land Surface Temperature and Evapotranspiration (PT-JPL) Data Across Korea (국내에서 ECOSTRESS 지표면 온도 및 증발산(PT-JPL) 자료의 검증)

  • Park, Ki Jin;Kim, Ki Young;Kim, Chan Young;Park, Jong Min
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.44 no.5
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    • pp.637-648
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    • 2024
  • The frequency of extreme weather events such as heavy and extreme rainfall has been increasing due to global climate change. Accordingly, it is essential to quantify hydrometeorological variables for efficient water resource management. Among the various hydro-meteorological variables, Land Surface Temperature (LST) and Evapotranspiration (ET) play key roles in understanding the interaction between the surface and the atmosphere. In Korea, LST and ET are mainly observed through ground-based stations, which also have limitation in obtaining data from ungauged watersheds, and thus, it hinders to estimate spatial behavior of LST and ET. Alternatively, remote sensing-based methods have been used to overcome the limitation of ground-based stations. In this study, we evaluated the applicability of the National Aeronautics and Space Administration's (NASA) ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) LST and ET data estimated across Korea (from July 1, 2018 to December 31, 2022). For validation, we utilized NASA's MODerate Resolution Imaging Spectroradiometer (MODIS) data and eddy covariance flux tower observations managed by agencies under the Ministry of Environment of South Korea. Overall, results indicated that ECOSTRESS-based LSTs showed similar temporal trends (R: 0.47~0.73) to MODIS and ground-based observations. The index of agreement also showed a good agreement of ECOSTRESS-based LST with reference datasets (ranging from 0.82 to 0.91), although it also revealed distinctive uncertainties depending on the season. The ECOSTRESS-based ET demonstrated the capability to capture the temporal trends observed in MODIS and ground-based ET data, but higher Mean Absolute Error and Root Mean Square Error were also exhibited. This is likely due to the low acquisition rate of the ECOSTRESS data and environmental factors such as cooling effect of evapotranspiration, overestimation during the morning. This study suggests conducting additional validation of ECOSTRESS-based LST and ET, particularly in topographical and hydrological aspects. Such validation efforts could enhance the practical application of ECOSTRESS for estimating basin-scale LST and ET in Korea.