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A Study on the Discourse Regarding the Lineage Transmission to Haewol in the Eastern Learning: Focused on Document Verification (해월의 동학 도통전수 담론 연구 - 문헌 고증을 중심으로 -)

  • Park Sang-kyu
    • Journal of the Daesoon Academy of Sciences
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    • v.48
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    • pp.41-155
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    • 2024
  • Among the records that attest to the period from July to August of 1863, when Suwun was believed to have transmitted the orthodox lineage to Haewol, the oldest documents are The Collection of Suwun's Literary Works (水雲文集), The Collection of Great Master Lord's Literary Works (大先生主文集), and The Records of Dao Origin of Master Choe's Literary Collection (崔先生文集道源記書, hereafter referred to as The Records of Dao Origin). The records regarding Suwun in these three documents are considered to have originated from the same context. The variances embedded in the three documents have led to arguments about which documents accurately reflect the fact of orthodox lineage transmission. Additionally, these variances highlight the necessity of a review regarding the characteristics of early Eastern Learning, such as its faith and organizational systems. Accordingly, by thoroughly examining these three documents, it is possible to elucidate the chronological order, establishment-date, accuracy, descriptive direction, and characteristics of the faith system of early Eastern Learning as these are reflected in each document. If successful, this examination would provide a clearer description of the developmental process of Eastern Learning from 1860 to 1880, facilitating a more in-depth analysis of the significance embedded in various forms of discourse on the movement's orthodox lineage transmission. In comparing the three documents and contrasting them with related sources, the results of the textual examination assert that the documents within the lineage of The Collection of Suwun's Literary Works, given they lack a clear record of the event regarding Haewol's orthodox lineage succession, may be the first draft of The Collection of Great Master Lord's Literary Works and The Records of Dao Origin, as these texts distinctly include that record. This reflects that Haewol's succession was not precisely recognized within and outside of the Eastern Learning order until the time when The Collection of Great Master Lord's Literary Works and The Records of Dao Origin were published. This is further attested to by the fact that during the late 1870s, when various Yeonwon (fountainhead) factions of Eastern Learning began to converge around Haewol, and his Yeonwon became the largest organization within Eastern Learning. At that point, the order's doctrine was reinterpreted, and its organization was reestablished. In this regard, it is necessary to view Eastern Learning after Suwun-especially the orthodox lineage transmission to Haewol-from a perspective that considers it more as competing forms of discourse than as a historical fact. This view enables a new perspective on Haewol's Eastern Learning, which forms a distinct layer from Suwun's, shedding light on the relationship between Haewol and the new religious movements in modern-day Korea.

Analysis of research trends for utilization of P-MFC as an energy source for nature-based solutions - Focusing on co-occurring word analysis using VOSviewer - (자연기반해법의 에너지원으로서 P-MFC 활용을 위한 연구경향 분석 - VOSviewer를 활용한 동시 출현단어 분석 중심으로 -)

  • Mi-Li Kwon;Gwon-Soo Bahn
    • Journal of Wetlands Research
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    • v.26 no.1
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    • pp.41-50
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    • 2024
  • Plant Microbial Fuel Cells (P-MFCs) are biomass-based energy technologies that generate electricity from plant and root microbial communities and are suitable for natural fundamental solutions considering sustainable environments. In order to develop P-MFC technology suitable for domestic waterfront space, it is necessary to analyze international research trends first. Therefore, in this study, 700 P-MFC-related research papers were investigated in Web of Science, and the core keywords were derived using VOSviewer, a word analysis program, and the research trends were analyzed. First, P-MFC-related research has been on the rise since 1998, especially since the mid to late 2010s. The number of papers submitted by each country was "China," "U.S." and "India." Since the 2010s, interest in P-MFCs has increased, and the number of publications in the Philippines, Ukraine, and Mexico, which have abundant waterfront space and wetland environments, is increasing. Secondly, from the perspective of research trends in different periods, 1998-2015 mainly carried out microbial fuel cell performance verification research in different environments. The 2016-2020 period focuses on the specific conditions of microbial fuel cell use, the structure of P-MFC and how it develops. From 2021 to 2023, specific research on constraints and efficiency improvement in the development of P-MFC was carried out. The P-MFC-related international research trends identified through this study can be used as useful data for developing technologies suitable for domestic waterfront space in the future. In addition to this study, further research is needed on research trends and levels in subsectors, and in order to develop and revitalize P-MFC technologies in Korea, research on field applicability should be expanded and policies and systems improved.

Teleseismic Travel Time Tomography for the Mantle Velocity Structure Beneath the Melanesian Region (원거리 지진 주시 토모그래피를 이용한 멜라네시아 지역의 맨틀 속도 구조 연구)

  • Jae-Hyung Lee;Sung-Joon Chang
    • Economic and Environmental Geology
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    • v.57 no.1
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    • pp.1-15
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    • 2024
  • The Melanesian region in the western Pacific is dominated by complex plate tectonics, with the largest oceanic plateau, the OntongJava plateau, and a hotspot, the Caroline Islands. To better understand the complex geodynamics of the region, we estimate P- and S-velocity models and 𝛿 (VP/VS) model by using relative teleseismic travel times measured at seismometers on land and the seafloor. Our results show high-velocity anomalies in the subduction zones of the Melanesian region to a depth of about 400 km, which is thought to be subducting Solomon Sea, Bismarck, and Australian plates along plate boundaries. Along subduction zones, positive 𝛿 (VP/VS) anomalies are found, which may be caused by partial melting due to dehydration. A broad high-velocity anomaly is observed at 600 km depth below the Ontong-Java plateau, with a negative 𝛿 (VP/VS) anomaly. This is thought to be a viscous and dry remnant of the Pacific plate that subducted at 45-25 Ma, with a low volume of fluids due to dehydration for a long period in the mantle transition zone. Beneath the Caroline Islands, a strong low-velocity anomaly is obseved to a depth of 800 km and appears to be connected to the underside of the remnant Pacific plate in the mantle transition zone. This suggests that the mantle plume originating in the lower mantle has been redirected due to the interaction with the remnant Pacific plate and has reached its current location. The mantle plume also has a positive 𝛿 (VP/VS) anomaly, which is thought to be due to the influence of embedded fluids or partial melting. A high-velocity anomaly, interpreted as an effect of the thick lithosphere beneath the Ontong-Java plateau, is observed down to 300 km depth with a negative 𝛿 (VP/VS) anomaly, which likely indicate that little fluid remains in the melt residue accumulated in the lithosphere.

The ecological response of the climate change indicator species, Korean fir (Abies koreana E. H. Wilson) (기후변화 지표종 구상나무(Abies koreana E. H. Wilson)의 생태학적 반응)

  • Yoon Seo Kim;Se Hee Kim;Jung Min Lee;Ji Won Park;Yeo Bin Park;Jae Hoon Park;Eui Joo Kim;Kyeong Mi Cho;Yoon Kyung Choi;Ji Hyun Seo;Joo Hyun Seo;Gyu Ri Kim;Ju Seon Lee;Do Hun Ryu;Min Sun Kim;Young Han You
    • Journal of Wetlands Research
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    • v.26 no.1
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    • pp.62-71
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    • 2024
  • To assess the ecological changes of Korean fir (Abies koreana E. H. Wilson) under climate change conditions, growth and physiological responses were analyzed over a 5-year period in a control group (outdoors) and in a treatment group where the temperature and CO2 levels were elevated to closely resemble RCP 4.5 conditions. The results showed an increasing trend in annual branch length of A.koreana in the climate change treatment group over time. While climate change conditions did not significantly impact the morphological differences of A.koreana leaves, they did influence the biomass of the leaves, suggesting that as climate change progresses, the productivity of A.koreana leaves may decline. On the other hand, the chlorophyll content in A.koreana under climate change conditions was higher in the climate change treatment group, whereas the photosynthesis rate, transpiration rate, water use efficiency and stomatal conductance was higher in the control group. This suggests that an environment with elevated temperature and CO2 could influence an increase in stomatal density, but having a negative impact on photosynthetic reactions. Further research on stomatal density under each environmental treatment will be required to confirm this hypothesis. Additionally, as this study only observed changes in leaf biomass, further empirical research should be considered to understand the changes in biomass of A.koreana under climate change conditions. In conclusion, the environmental adaptability of A.koreana is expected to weaken in the long term under elevated temperatures and CO2.

Awareness, need and demand for the amendment of medical device law according to the general characteristics of some dental hygienists (일부 치과위생사들의 일반적 특성에 따른 의료기사법 개정에 대한 인식, 필요 및 요구도)

  • Lee, Hyeon-Jeong;Kwak, Ji-Won;Lee, Dong-Ha;Lee, Hyeon-Hee;Jeong, Hae-Mi;Joo, Soo-Yeon;Seong, Mi-Gyung
    • Journal of Korean Dental Hygiene Science
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    • v.1 no.1
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    • pp.23-36
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    • 2018
  • This research has been conducted from June 1, 2017 to August 25, 2017 for the dental hygienists working in Busan and Gyeongnam area, to provide necessary basic data for the purpose of revision of the relating laws from the analysis of their understanding and perspective on such laws through 262 subjects' questionnaire. Its analysis of their perspectives are as follows. 1. The common characteristics of the subjects are that 40.1% of them are under 25, and their working period was under three years with the 38.9%, and as for their marital status, 70.2% were single, the final education of 80.2% were associated degrees. Their working areas are centered in Gyeongsangnam-do province with 91.2%, the workplace type is for the dental clinic with 80.2%. 2. The comparison of the view point of the medical(technician) law according to the characteristics of the research subjects differed only whether or not the completion of the education, and as a result of the comparison according to the characteristics of those subjects understanding the details of the medical(technician) law, there was a significant difference saying "the current law has clear job description" depending on the working area or "the job duty is definite" depending on the job experience and job details. As for those saying "the job duty is definite", there was also significant difference depending upon marital status, final education and work details. There was no significant difference in all characteristics from findings of the necessity of legal system according to the subjects not understanding the medical(technician) law. 3. As a result of comparing the necessity of the medical(technician) law according to the characteristics of the research subjects, it was found that all the subjects accepted the necessity of the medical law revision including the dental hygienist in the medical person. The "necessity of the professional dental hygienist system" showed a significant difference depending upon the final education and medical institution type. Among the triggering factors in its amendment, there showed significant difference in the "cooperation of other organizations" and "solution of medical law problems" only in the final education. 4. As a result of comparison of the needs of the medical(technician) law revision according to the characteristics of the research subjects, it was found that the significant traits related to the age and job details showed "Legal responsibility would be increased" when the medical law is revised, in case that "it will help broaden the job extension", there showed a significant difference in career, final education, and working institution, and job details. "Legal protection is possible" showed significant difference except the age group and working area, and "it help the system settlement" showed in the final education. There was a significant difference in career, final education, and job details that "I can regulate the education and field practice", and the same in "my status will be improved" depending upon the final education, work area, and job details. Accordingly, in this research, for the establishment of more professional and comprehensive dental health service as suggested from the demand and necessity toward the medical(technician) Law by the dental hygienists.

Study on data preprocessing methods for considering snow accumulation and snow melt in dam inflow prediction using machine learning & deep learning models (머신러닝&딥러닝 모델을 활용한 댐 일유입량 예측시 융적설을 고려하기 위한 데이터 전처리에 대한 방법 연구)

  • Jo, Youngsik;Jung, Kwansue
    • Journal of Korea Water Resources Association
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    • v.57 no.1
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    • pp.35-44
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    • 2024
  • Research in dam inflow prediction has actively explored the utilization of data-driven machine learning and deep learning (ML&DL) tools across diverse domains. Enhancing not just the inherent model performance but also accounting for model characteristics and preprocessing data are crucial elements for precise dam inflow prediction. Particularly, existing rainfall data, derived from snowfall amounts through heating facilities, introduces distortions in the correlation between snow accumulation and rainfall, especially in dam basins influenced by snow accumulation, such as Soyang Dam. This study focuses on the preprocessing of rainfall data essential for the application of ML&DL models in predicting dam inflow in basins affected by snow accumulation. This is vital to address phenomena like reduced outflow during winter due to low snowfall and increased outflow during spring despite minimal or no rain, both of which are physical occurrences. Three machine learning models (SVM, RF, LGBM) and two deep learning models (LSTM, TCN) were built by combining rainfall and inflow series. With optimal hyperparameter tuning, the appropriate model was selected, resulting in a high level of predictive performance with NSE ranging from 0.842 to 0.894. Moreover, to generate rainfall correction data considering snow accumulation, a simulated snow accumulation algorithm was developed. Applying this correction to machine learning and deep learning models yielded NSE values ranging from 0.841 to 0.896, indicating a similarly high level of predictive performance compared to the pre-snow accumulation application. Notably, during the snow accumulation period, adjusting rainfall during the training phase was observed to lead to a more accurate simulation of observed inflow when predicted. This underscores the importance of thoughtful data preprocessing, taking into account physical factors such as snowfall and snowmelt, in constructing data models.

What are the Characteristics and Future Directions of Domestic Angel Investment Research? (국내 엔젤투자 연구의 특징과 향후 방향은 무엇인가?)

  • Min Kim;Byung Chul Choi;Woo Jin Lee
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.6
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    • pp.57-70
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    • 2023
  • The investigation delved into 457 pieces of scholarly work, encompassing articles, published theses, and dissertations from the National Research Foundation of Korea, spanning the period of the 1997 IMF financial crisis up to 2022. The materials were sourced using terms such as 'angel investment', 'angel investor', and 'angel investment attraction'. The initial phase involved filtering out redundant entries from the preliminary collection of 267 works, leaving aside pieces that didn't pertain directly to angel investment as indicated in their abstracts. The next stage of the analysis involved a more rigorous selection process. Out of 43 papers earmarked in the preceding cut, only 32 were chosen. The criteria for this focused on the exclusion of conference presentations, articles that were either not submitted or inconclusive, and those that duplicated content under different titles. The final selection of 32 papers underwent a thorough systematic literature review. These documents, all pertinent to angel investment in South Korea, were scrutinized under five distinct categories: 1) publication year, 2) themes of research, 3) strategies employed in the studies, 4) participants involved in the research, and 5) methods of research utilized. This meticulous process illuminated the existing landscape of angel investment studies within Korea. Moreover, this study pinpointed gaps in the current body of research, offering guidance on future scholarly directions and proposing social scientific theories to further enrich the field of angel investment studies and analysis also seeks to pinpoint which areas require additional exploration to energize the field of angel investment moving forward. Through a comprehensive review of literature, this research intends to validate the establishment of future research trajectories and pinpoint areas that are currently and relatively underexplored in Korea's angel investment research stream. This study revealed that current research on domestic angel investment is concentrated on several areas: 1) the traits of angel investors, 2) the motivations behind angel investing, 3) startup ventures, 4) relevant institutions and policies, and 5) the various forms of angel investments. It was determined that there is a need to broaden the scope of research to aid in enhancing and stimulating the scale of domestic angel investing. This includes research into performance analysis of angel investments and detailed case studies in the field. Furthermore, the study emphasizes the importance of diversifying research efforts. Instead of solely focusing on specific factors like investment types, startups, accelerators, venture capital, and regulatory frameworks, there is a call for research that explores a variety of associated variables. These include aspects related to crowdfunding and return on investment in the context of angel investing, ensuring a more holistic approach to research in this domain. Specifically, there's a clear need for more detailed studies focusing on the relationships with variables that serve as dependent variables influencing the outcomes of angel investments. Moreover, it's essential to invigorate both qualitative and quantitative research that delves into the theoretical framework from multiple perspectives. This involves analyzing the structure of variables that have an impact on angel investments and the decisions surrounding these investments, thereby enriching the theoretical foundation of this field. Finally, we presented the direction of development for future research by confirming that the effect on the completeness of the business plan is high or low depending on the satisfaction of the entrepreneurs in addition to the components.

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Study on the Possibility of Estimating Surface Soil Moisture Using Sentinel-1 SAR Satellite Imagery Based on Google Earth Engine (Google Earth Engine 기반 Sentinel-1 SAR 위성영상을 이용한 지표 토양수분량 산정 가능성에 관한 연구)

  • Younghyun Cho
    • Korean Journal of Remote Sensing
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    • v.40 no.2
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    • pp.229-241
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    • 2024
  • With the advancement of big data processing technology using cloud platforms, access, processing, and analysis of large-volume data such as satellite imagery have recently been significantly improved. In this study, the Change Detection Method, a relatively simple technique for retrieving soil moisture, was applied to the backscattering coefficient values of pre-processed Sentinel-1 synthetic aperture radar (SAR) satellite imagery product based on Google Earth Engine (GEE), one of those platforms, to estimate the surface soil moisture for six observatories within the Yongdam Dam watershed in South Korea for the period of 2015 to 2023, as well as the watershed average. Subsequently, a correlation analysis was conducted between the estimated values and actual measurements, along with an examination of the applicability of GEE. The results revealed that the surface soil moisture estimated for small areas within the soil moisture observatories of the watershed exhibited low correlations ranging from 0.1 to 0.3 for both VH and VV polarizations, likely due to the inherent measurement accuracy of the SAR satellite imagery and variations in data characteristics. However, the surface soil moisture average, which was derived by extracting the average SAR backscattering coefficient values for the entire watershed area and applying moving averages to mitigate data uncertainties and variability, exhibited significantly improved results at the level of 0.5. The results obtained from estimating soil moisture using GEE demonstrate its utility despite limitations in directly conducting desired analyses due to preprocessed SAR data. However, the efficient processing of extensive satellite imagery data allows for the estimation and evaluation of soil moisture over broad ranges, such as long-term watershed averages. This highlights the effectiveness of GEE in handling vast satellite imagery datasets to assess soil moisture. Based on this, it is anticipated that GEE can be effectively utilized to assess long-term variations of soil moisture average in major dam watersheds, in conjunction with soil moisture observation data from various locations across the country in the future.

Spawning Season and Growth of Korean Dark Sleeper, Odontobutis platycephala in Jaho Stream, Korea (자호천에 서식하는 한국고유종 동사리(Odontobutis platycephala)의 산란시기와 성장)

  • Hwa-Keun Byeon
    • Korean Journal of Environment and Ecology
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    • v.38 no.2
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    • pp.148-155
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    • 2024
  • This study investigated the ecological characteristics of Odontobutis platycephala at Jaho stream from January to December 2022. The riverbed structure of the species' habitat was rich in cobble and pebble. The water was deep, ranging from 22 to 153 cm, with an average of 64 cm, and the stream velocity was rapid at 0.89 (0.42-1.46) m/sec. The ratio of females to males was 1:1.02, and the total length of collected individuals ranged from 38 to 156 mm. The age according to the total length frequency distribution as of May indicated that the group with a total length of 38-69 mm was one year old, the group with 60-99 mm was two years old, the group with 100-139 mm was three years old, and the group 140-156 mm was four years or older. As a secondary gender characteristic, the genital papilla was cylindrical in females and cone-shaped with a pointed tip in males. Some females with a length ranging from 60 to 69 mm and all females 70 mm or longer were sexually mature. Some males with a length ranging from 70 to 79 mm and all males 80 mm or longer were sexually mature. The spawning season was from May to July, and the water temperature was between 17 ℃ and 28 ℃ during that period. The prosperous spawning season was June (24 ℃). The average number of eggs in the ovaries was 988 (284-2,722) per mature female, and the mature eggs were yellowish and spherical with a mean diameter of 1.46 (1.19-1.71) mm. The correlation between total length and body weight is BW=0.00000006TL3.12 with the constant a as 0.00000006 and the parameter b as 3.12. The mean condition factor (K) was 1.44 (0.96-2.26), and the slope was negative at -0.0007

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.