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Development of tracer concentration analysis method using drone-based spatio-temporal hyperspectral image and RGB image (드론기반 시공간 초분광영상 및 RGB영상을 활용한 추적자 농도분석 기법 개발)

  • Gwon, Yeonghwa;Kim, Dongsu;You, Hojun;Han, Eunjin;Kwon, Siyoon;Kim, Youngdo
    • Journal of Korea Water Resources Association
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    • v.55 no.8
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    • pp.623-634
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    • 2022
  • Due to river maintenance projects such as the creation of hydrophilic areas around rivers and the Four Rivers Project, the flow characteristics of rivers are continuously changing, and the risk of water quality accidents due to the inflow of various pollutants is increasing. In the event of a water quality accident, it is necessary to minimize the effect on the downstream side by predicting the concentration and arrival time of pollutants in consideration of the flow characteristics of the river. In order to track the behavior of these pollutants, it is necessary to calculate the diffusion coefficient and dispersion coefficient for each section of the river. Among them, the dispersion coefficient is used to analyze the diffusion range of soluble pollutants. Existing experimental research cases for tracking the behavior of pollutants require a lot of manpower and cost, and it is difficult to obtain spatially high-resolution data due to limited equipment operation. Recently, research on tracking contaminants using RGB drones has been conducted, but RGB images also have a limitation in that spectral information is limitedly collected. In this study, to supplement the limitations of existing studies, a hyperspectral sensor was mounted on a remote sensing platform using a drone to collect temporally and spatially higher-resolution data than conventional contact measurement. Using the collected spatio-temporal hyperspectral images, the tracer concentration was calculated and the transverse dispersion coefficient was derived. It is expected that by overcoming the limitations of the drone platform through future research and upgrading the dispersion coefficient calculation technology, it will be possible to detect various pollutants leaking into the water system, and to detect changes in various water quality items and river factors.

A Study Seeking the Practical Implementation of the Yellow Sea Large Marine Ecosystem Project (황해광역해양생태계 프로젝트의 실효성 확보에 관한 연구)

  • Kim, Jin-kyung;Kown, Suk-jae;Lee, Sang-il
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.7
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    • pp.987-994
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    • 2021
  • The Yellow sea, as described in article 123 of UNCLOS, is semi-enclosed sea surrounded by the Republic of Korea, the People's Republic of China and North Korea. In addition, the Yellow Sea is one of the 66 large marine ecosystems as it contains large amounts of marine resources. According to article 194 of UNCLOS, states should be aware of rights and duties with respect to the protection and preservation of the marine environment to be engaged with countries directly as regional entity or indirectly. Therefore, the legal blank is urgent in terms of trans-boundary environmental pollutant issues. The UNDP has conducted a project called Yellow Sea Large Marine Ecosystem (YSLME) which has reached the 2nd phase. The project has some notable achievements, namely performing joint activities on analysis of diagnostic trans-boundary issues in collaboration with China and South Korea, developing a strategic action plan based on TDA, and establishing regional strategic action plan. However, on the other hand, the project could not reflect the full participation of North Korea as a state party. As a result, the project has a limitation on effective implementation of RSAP. Therefore, this study focuses on the suggestion of a legally-binding trilateral treaty as a blue print for the next, 3rd phase of the project. By analyzing the best practice of the Wadden Sea Trilateral Treaty case, the study verifies the validity of legislative measures on establishing and managing a legally-binding trilateral YSLME Commission. By suggesting a three phase treaty, incorporating a joint declaration by establishing the commission, the signing of the treaty, and formulating an umbrella convention and implementation arrangement, the study expects to guarantee the consistency and sustainability of the trilateral treaty regardless of political issues pertaining to North Korea.

A study on the nutrient intake of the elderly in Korea based on activity limitations: data from the 2019 Korea National Health and Nutrition Examination Survey (활동제한에 따른 한국 노인의 식생활 및 영양섭취 평가: 2019년 국민건강영양조사 자료를 이용하여)

  • Kim, Soyoung;Lee, Youngmi
    • Journal of Nutrition and Health
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    • v.55 no.5
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    • pp.543-557
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    • 2022
  • Purpose: Conditions that limit activity constitute one of the important factors that threaten the health of the elderly. This study sought to analyze the dietary habits and nutritional intake status of the Korean elderly who were faced with activity limitations. Methods: Utilizing data from the 2019 Korea National Health and Nutrition Examination Survey, we classified 1,383 elderly people aged 65 and over into 2 groups: those with activity limitations (n = 222, LG) and those without (n = 1,161, NG). We conducted a comparative analysis of the general characteristics, dietary habits, intake of major food groups, energy, and major nutrients. The nutrient adequacy ratio (NAR), index of nutritional quality (INQ), and healthy eating practices were also analyzed. Complex sampling analysis was utilized for all the analyses with energy intake and socio-demographic variables adjusted. Results: The average age (73.8 years) of members of the LG was higher than those of the NG (72.6 years; p = 0.010). A higher percentage of participants in the LG lived alone (28.1%) compared to those in NG (17.2%; p = 0.004). The LG participants tended to regard their health status as "bad" or "very bad" (62.7%) more often than those in the NG (19.3%; p < 0.001). The LG subjects ate breakfast less frequently (p = 0.054) and ate out significantly less often than the NG subjects (p < 0.001). The LG subjects ate more grain (p = 0.001), fewer seeds (p = 0.014) and vegetables (p = 0.039). Carbohydrate made up a large percentage of their energy intake (p = 0.026). The LG subjects had significantly lower NARs of energy (p = 0.021), protein (p = 0.031), and riboflavin (p = 0.037). The LG participants also had a significantly lower rate of healthy eating practices (22.7%) compared to those in the NG (37.8%; p < 0.001). Conclusion: Activity-limited elderly, despite their need for appropriate dietary management, were poorly nourished. They were likely to live alone, thereby making it hard to provide them with social support. Hence, there is a need to provide nutrition education and policy support for the elderly bearing the burden of limited activity.

Influence of finish line design on the marginal fit of nonprecious metal alloy coping fabricated by 3D printing, milling and casting using CAD-CAM (CAD-CAM을 이용한 3D printing, milling, casting 방법의 비귀금속 코핑의 지대치 변연 적합도 연구)

  • Seo-Rahng Kim;Myung-Joo Kim;Ji-Man Park;Seong-Kyun Kim;Seong-Joo Heo;Jai-Young Koak
    • The Journal of Korean Academy of Prosthodontics
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    • v.61 no.1
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    • pp.1-17
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    • 2023
  • Purpose. The purpose of this study was to examine the correlation between the finish line designs and the marginal adaptation of nonprecious metal alloy coping produced by different digital manufacturing methods. Materials and methods. Nonprecious metal alloy copings were made respectively from each master model with three different methods; SLS, milling and casting by computer aided design and computer aided manufacturing (CAD-CAM). Twelve copings were made by each method resulting in 72 copings in total. The measurement was conducted at 40 determined reference points along the circumferential margin with the confocal laser scanning microscope at magnification ×150. Results. Mean values of marginal gap of laser sintered copings were 11.8 ± 7.4 ㎛ for deep chamfer margin and 6.3 ± 3.5 ㎛ for rounded shoulder margin and the difference between them was statistically significant (P < .0001). Mean values of marginal gap of casted copings were 18.8 ± 20.2 ㎛ for deep chamfer margin and 33 ± 20.5 ㎛ for rounded shoulder margin and the difference between them was significant (P = .0004). Conclusion. Within the limitation of this study, the following conclusions were drawn. 1. The variation of finish line design influences the marginal adaptation of laser sintered metal coping and casted metal coping. 2. Laser sintered copings with rounded shoulder margin had better marginal fit than deep chamfer margin. 3. Casted copings with deep chamfer margin had better marginal fit than rounded shoulder margin. 4. According to the manufacturing method, SLS system showed the best marginal fit among three different methods. Casting and milling method followed that in order.

A Generalized Adaptive Deep Latent Factor Recommendation Model (일반화 적응 심층 잠재요인 추천모형)

  • Kim, Jeongha;Lee, Jipyeong;Jang, Seonghyun;Cho, Yoonho
    • Journal of Intelligence and Information Systems
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    • v.29 no.1
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    • pp.249-263
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    • 2023
  • Collaborative Filtering, a representative recommendation system methodology, consists of two approaches: neighbor methods and latent factor models. Among these, the latent factor model using matrix factorization decomposes the user-item interaction matrix into two lower-dimensional rectangular matrices, predicting the item's rating through the product of these matrices. Due to the factor vectors inferred from rating patterns capturing user and item characteristics, this method is superior in scalability, accuracy, and flexibility compared to neighbor-based methods. However, it has a fundamental drawback: the need to reflect the diversity of preferences of different individuals for items with no ratings. This limitation leads to repetitive and inaccurate recommendations. The Adaptive Deep Latent Factor Model (ADLFM) was developed to address this issue. This model adaptively learns the preferences for each item by using the item description, which provides a detailed summary and explanation of the item. ADLFM takes in item description as input, calculates latent vectors of the user and item, and presents a method that can reflect personal diversity using an attention score. However, due to the requirement of a dataset that includes item descriptions, the domain that can apply ADLFM is limited, resulting in generalization limitations. This study proposes a Generalized Adaptive Deep Latent Factor Recommendation Model, G-ADLFRM, to improve the limitations of ADLFM. Firstly, we use item ID, commonly used in recommendation systems, as input instead of the item description. Additionally, we apply improved deep learning model structures such as Self-Attention, Multi-head Attention, and Multi-Conv1D. We conducted experiments on various datasets with input and model structure changes. The results showed that when only the input was changed, MAE increased slightly compared to ADLFM due to accompanying information loss, resulting in decreased recommendation performance. However, the average learning speed per epoch significantly improved as the amount of information to be processed decreased. When both the input and the model structure were changed, the best-performing Multi-Conv1d structure showed similar performance to ADLFM, sufficiently counteracting the information loss caused by the input change. We conclude that G-ADLFRM is a new, lightweight, and generalizable model that maintains the performance of the existing ADLFM while enabling fast learning and inference.

Hazardous Metal Content in Tattoo Cosmetics and Tattoo Inks (타투화장품 및 문신용 염료의 유해금속 함량 연구)

  • Mi Sun Kim;Su Un Kim;Sam Ju Jung;Young Eun Kim;Min Jung Kim;Myung Sook Lee;In Sook Hwang
    • Journal of Environmental Health Sciences
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    • v.49 no.2
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    • pp.66-77
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    • 2023
  • Background: Along with the increase in consumer interest in and consumption of tattoo products, the controversy over harmful heavy metals associated with the use of tattoo cosmetics is also increasing. Therefore, investigation of hazardous metals in these tattoo products is needed. Objectives: This study was performed to provide useful data for establishing reasonable standards to securely manage tattoo cosmetics, tattoo stickers, and tattoo inks distributed in the market. Methods: Thirteen kinds of hazardous metal contents (Pb, As, Cd, Sb, Ni, Co, Cu, Cr, Se, Ba, Zn, Sn, and Hg) were analyzed for 23 tattoo cosmetics, ten tattoo stickers, and 16 tattoo inks. Hg was measured through the combustion-gold amalgamation method, and other hazardous metals were measured by inductively coupled plasma-mass spectrometry (ICP-MS) after acidic decomposition using a microwave apparatus. Results: The detected ranges of Pb, As, Cd, Sb, Ni, and Hg in tattoo cosmetics were 0.07~1.18, 0.06~0.41, ND~0.07, 0.01~3.44, 0.12~2.75, and ND~0.01 ㎍/g, respectively. All of the hazardous metals detected were below the recommended maximum standards of the Ministry of Food and Drug Safety. The mean amount of Pb detected in tattoo stickers for children was 0.24 ㎍/kg and Cd was not detected, meaning both metals met the recommended criteria. There was no statistically significant difference in all measured metals between children's tattoo stickers and adults' tattoo stickers. In the results of the study on the hazardous metal content of tattoo inks, four products (25%) for Pb, one product (6%) for As, 13 products (81%) for Ni, four products (25%) for Cu, and five products (31%) for Zn exceeded the recommended standards approved by the government. The highest predicted exposure amount for hazardous metals exceeding the recommended level of tattoo inks in a single tattooing was 5.69 ㎍/kg for Ni, 8.51 ㎍/kg for Zn, 0.44 ㎍/kg for Pb, 8.07 ㎍/kg for Cu, 0.44 ㎍/kg for As, and 71.36 ㎍/kg for Ba. Conclusions: It is necessary to prepare criteria for content limitation for the management of Co, Cr, Ba and Se tattoo cosmetics, and tattoo inks require thorough quality control.

Analysis of Global Success Factors of K-pop Music (K-pop 음악의 글로벌 성공 요인 분석)

  • Lee, Kate Seung-Yeon;Chang, Min-Ho
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.4
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    • pp.1-15
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    • 2019
  • Psy's Gangnam style in 2012 showed K-pop's potential for global growth and BTS proved it by reaching three consecutive Billboard No.1. The success in the global music market brings tremendous economical and cultural power. This study is conducted for the continuous growth of K-pop music in the global music market by analyzing the musical factor of K-pop's global success. The top 20 most-viewed K-pop MV on Youtube is chosen as a research subject because Youtube is a worldwide platform that reflects global popularity. For the process of K-pop music creation, the role of the composer is expanded and many overseas producers participate in music creation. All 20 songs are created by the collective creation system and there is a consecutive collaboration between the main producers and certain artists. The top 20 most viewed K-pop songs have the musical characteristics of transnational genre convergence, hook songs, sophisticated sounds, frequent use of English lyrics, a reflection of the latest global trends, rhythm optimized for dance and clear concept. It makes the K-pop song easily remembered and familiar to overseas listeners. K-pop's healthy and fresh theme brings emotional empathy and reflects Korean sentiments. K-pop's global success is not a coincidence, but a result of continuous efforts to advance overseas. Some critics criticize K-pop's musical style is similar and it shows K-pop's limitation but K-pop progressed its musical evolution. By keeping the merits of K-pop's success factors and complementing its weak points, K-pop will continue its popularity and increase influence in the global music market.

A Study on Verifying the Morality behind 'Mutual Beneficence': A Phenomenological Investigation on the 'Propensity towards Sympathy' (상생적 관계형성을 위한 도덕성 확인에 관한 연구 - '공감적 성향'에 대한 현상학적 고찰 -)

  • Chung, Byung-hwa
    • Journal of the Daesoon Academy of Sciences
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    • v.28
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    • pp.103-131
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    • 2017
  • As the establishment of self-identity is based on 'Relationships of Mutual Beneficence,' the formation of 'Relationships of Mutual Beneficence' is the only road to the security and confirmation of self-existence. But given that our ordinary life almost entirely consists of actions objectifying others, the formation of 'Relationships of Mutual Beneficence' is by no means easy. The formation of 'Relationships of Mutual Beneficence' should be based on morality, controlling self-desire, and not objectifying others. Philosophy based on a priori reasoning describes self-control over selfdesire as the domination of the body through a priori reasoning. But this practical philosophy cannot present a self-evidential internal motivation behind moral actions. Due to this, the application of moral order given by a priori reasoning in response to reality is likely to be reinterpreted on basis of self-interest. With regards to this, the 'propensity towards sympathy' is given as new moral norm. The 'propensity towards sympathy' as emotion is direct and consistent given that feeling occurs prior to thinking. The 'propensity towards sympathy' is intuitive in the sense that it is an instinctual response preceeding a reasoned judgment. The 'propensity towards sympathy,' as a natural moral emotion, is self-validating given that all human beings know it and practice it. But previous studies on the 'propensity towards sympathy' have an obvious limitation because they adopt phenomenological approaches to the 'propensity towards sympathy' which eschew the investigation of morality. Though they present the 'propensity towards sympathy' as a natural emotion based on body rather than reason, they do not philosophically explain the 'propensity towards sympathy.' Thus the 'propensity towards sympathy' as a natural moral emotion is likely to be interpreted as a subjective and relative moral norm. This paper philosophically explains that the 'propensity towards sympathy' is a universal moral norm on the basis of Merleau-Ponty's 'flesh.' 'Flesh' is formed as the entanglement between oneself and others and presents the 'propensity towards sympathy' as its philosophical basis. In other words, 'flesh' formed as the mixture or entanglement between oneself and others is the material foundation upon which one can activate the 'propensity towards sympathy.' This paper's approach to the 'propensity of sympathy' can be desribed as a phenomenological approach to the 'propensity towards sympathy' as a universal moral norm.

Research on the Digital Twin Policy for the Utilization of Administrative Services (행정서비스 활용을 위한 디지털 트윈 정책 연구)

  • Jina Ok;Soonduck Yoo;Hyojin Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.3
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    • pp.35-43
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    • 2023
  • The purpose of this study is to research digital twin policies for the use of administrative services. The study was conducted through a mobile survey of 1,000 participants, and the results are as follows. First, in order to utilize digital twin technology, it is necessary to first identify appropriate services that can be applied from the perspective of Gyeonggi Province. Efforts to identify digital twin services that are suitable for Gyeonggi Province's field work should be prioritized, and this should lead to increased efficiency in the work. Second, Gyeonggi Province's digital twin administrative services should prevent duplication with central government projects and establish a model that can be connected and utilized. It should be driven around current issues in Gyeonggi Province and the demands of citizens for administrative services. Third, to develop Gyeonggi Province's digital twin administrative services, a standard model development plan through participation in pilot projects should be considered. Gyeonggi Province should lead the project as the main agency and promote it through a collaborative project agreement. It is suggested that a support system for the overall project be established through the Gyeonggi Province Digital Twin Advisory Committee. Fourth, relevant regulations and systems for the construction, operation, and management of dedicated departments and administrative services should be established. To achieve the realization of digital twins in Gyeonggi Province, a dedicated organization that can perform various roles in project promotion and operation, as well as legal and institutional improvements, is necessary. To designate a dedicated organization, it is necessary to consider expanding and reorganizing existing departments and evaluating the operation of newly established departments. The limitation of this study is that it only surveyed participants from Gyeonggi Province, and it is recommended that future research be conducted nationwide. The expected effect of this study is that it can serve as a foundational resource for applying digital twin services to public work.

Prediction of Key Variables Affecting NBA Playoffs Advancement: Focusing on 3 Points and Turnover Features (미국 프로농구(NBA)의 플레이오프 진출에 영향을 미치는 주요 변수 예측: 3점과 턴오버 속성을 중심으로)

  • An, Sehwan;Kim, Youngmin
    • Journal of Intelligence and Information Systems
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    • v.28 no.1
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    • pp.263-286
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    • 2022
  • This study acquires NBA statistical information for a total of 32 years from 1990 to 2022 using web crawling, observes variables of interest through exploratory data analysis, and generates related derived variables. Unused variables were removed through a purification process on the input data, and correlation analysis, t-test, and ANOVA were performed on the remaining variables. For the variable of interest, the difference in the mean between the groups that advanced to the playoffs and did not advance to the playoffs was tested, and then to compensate for this, the average difference between the three groups (higher/middle/lower) based on ranking was reconfirmed. Of the input data, only this year's season data was used as a test set, and 5-fold cross-validation was performed by dividing the training set and the validation set for model training. The overfitting problem was solved by comparing the cross-validation result and the final analysis result using the test set to confirm that there was no difference in the performance matrix. Because the quality level of the raw data is high and the statistical assumptions are satisfied, most of the models showed good results despite the small data set. This study not only predicts NBA game results or classifies whether or not to advance to the playoffs using machine learning, but also examines whether the variables of interest are included in the major variables with high importance by understanding the importance of input attribute. Through the visualization of SHAP value, it was possible to overcome the limitation that could not be interpreted only with the result of feature importance, and to compensate for the lack of consistency in the importance calculation in the process of entering/removing variables. It was found that a number of variables related to three points and errors classified as subjects of interest in this study were included in the major variables affecting advancing to the playoffs in the NBA. Although this study is similar in that it includes topics such as match results, playoffs, and championship predictions, which have been dealt with in the existing sports data analysis field, and comparatively analyzed several machine learning models for analysis, there is a difference in that the interest features are set in advance and statistically verified, so that it is compared with the machine learning analysis result. Also, it was differentiated from existing studies by presenting explanatory visualization results using SHAP, one of the XAI models.