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Forest Burned Area Detection Using Landsat 8/9 and Sentinel-2 A/B Imagery with Various Indices: A Case Study of Uljin (Landsat 8/9 및 Sentinel-2 A/B를 이용한 울진 산불 피해 탐지: 다양한 지수를 기반으로 다시기 분석)

  • Kim, Byeongcheol;Lee, Kyungil;Park, Seonyoung;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.38 no.5_2
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    • pp.765-779
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    • 2022
  • This study evaluates the accuracy in identifying the burned area in South Korea using multi-temporal data from Sentinel-2 MSI and Landsat 8/9 OLI. Spectral indices such as the Difference Normalized Burn Ratio (dNBR), Relative Difference Normalized Burn Ratio (RdNBR), and Burned Area Index (BAI) were used to identify the burned area in the March 2022 forest fire in Uljin. Based on the results of six indices, the accuracy to detect the burned area was assessed for four satellites using Sentinel-2 and Landsat 8/9, respectively. Sentinel-2 and Landsat 8/9 produce images every 16 and 10 days, respectively, although it is difficult to acquire clear images due to clouds. Furthermore, using images taken before and after a forest fire to examine the burned area results in a rapid shift because vegetation growth in South Korea began in April, making it difficult to detect. Because Sentinel-2 and Landsat 8/9 images from February to May are based on the same date, this study is able to compare the indices with a relatively high detection accuracy and gets over the temporal resolution limitation. The results of this study are expected to be applied in the development of new indices to detect burned areas and indices that are optimized to detect South Korean forest fires.

A Study on the Seismic Response Formula for Improvement of Seismic Design Code of Water Treatment Underground Structures (수처리 지중구조물의 내진설계 기준 개선을 위한 지진 응답 제안식의 관한 연구)

  • Lee, Joung-Bae;Bae, Sang-Soo;Chung, Kwang-Mo;Bang, Myung-Seok
    • Journal of the Korean Geosynthetics Society
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    • v.21 no.3
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    • pp.41-48
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    • 2022
  • Generally it was known that member forces in the earthquake resistant design is lower than those in the general design. But it is not true in cases of water treatment underground structures, which is different in each case like water treatment plant, sedimentation basin, and utility-pipe conduit. Also, looking at the scale of earthquakes that have recently occurred in Korea, large-scale earthquakes are frequent, so when the magnitude of the design seismic force increases, it is necessary to investigate the seismic behavior of the water treatment underground structure and to deal with it. In this study the change rate of member forces was investigated by the change of design load factor (earthquake acceleration design criteria), earth depth, underground water level. The pseudo-static analysis and response displacement method was applied, and various analyzes were conducted depending on the ground water and soil depth. The proposed formula in this study will be efficient when the earthquake design code of water treatment underground structures is revised.

The PIC Bumper Beam Design Method with Machine Learning Technique (머신 러닝 기법을 이용한 PIC 범퍼 빔 설계 방법)

  • Ham, Seokwoo;Ji, Seungmin;Cheon, Seong S.
    • Composites Research
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    • v.35 no.5
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    • pp.317-321
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    • 2022
  • In this study, the PIC design method with machine learning that automatically assigning different stacking sequences according to loading types was applied bumper beam. The input value and labels of the training data for applying machine learning were defined as coordinates and loading types of reference elements that are part of the total elements, respectively. In order to compare the 2D and 3D implementation method, which are methods of representing coordinate value, training data were generated, and machine learning models were trained with each method. The 2D implementation method is divided FE model into each face and generating learning data and training machine learning models accordingly. The 3D implementation method is training one machine learning model by generating training data from the entire finite element model. The hyperparameter were tuned to optimal values through the Bayesian algorithm, and the k-NN classification method showed the highest prediction rate and AUC-ROC among the tuned models. The 3D implementation method revealed higher performance than the 2D implementation method. The loading type data predicted through the machine learning model were mapped to the finite element model and comparatively verified through FE analysis. It was found that 3D implementation PIC bumper beam was superior to 2D implementation and uni-stacking sequence composite bumper.

A Study on the Development of a Full-Cycle Smart City Living Lab Model (전주기형 스마트시티 리빙랩 모델 개발 연구)

  • Park, Jun-Ho;Park, Jeong-Woo;Nam, Kwang-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.162-170
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    • 2021
  • The Smart City Living Lab is becoming important as a local innovation platform to develop urban solutions. In January 2018, the 4th industrial innovation committee, which was a direct subordinate from the president, empathized citizens' participation and their roles within the Smart City [Urban Innovation and Future Growth Engine-Creating Smart City Strategy]. This was the starting point of the living lab. The central government and local governments have been promoting various types of living labs to encourage citizens to participate. On the other hand, due to the lack of systematic concepts and theories for practicing and structuring living labs, the practice is not performed well. This study aimed to develop systematic approaches and implementation methods of the public-led Smart City Living Lab. The Full-cycle Smart City living Lab model was designed by integrating smart city living lab work processes, as suggested in the standards of the national land plan, double design diamond framework, which is a type of innovative design methodology, and design thinking process. The entire cycle Smart City living lab model requires four components to practice the living lab, such as framework, module, process, and methodologies. In the future, this model is expected to be incorporated in the Smart City Living Lab.

Comparative Analysis of Evaluation Methods for Image Segmentation Results (영상분할 결과 평가 방법의 적용성 비교 분석)

  • Seo, Won-Woo;Lee, Kyu-Sung
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.257-274
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    • 2021
  • Although image segmentation is a critical part of object-based analysis of high resolution imagery, there has been lack of studies to evaluate the quality of image segmentation. In this study, we aimed to find practical and effective methods to obtain optimal parameters for image segmentation. Evaluations of image segmentation are divided into unsupervised, supervised, and qualitative visual interpretation methods. Using the multispectral UAV images, sampled from urban and forest over the Incheon Metropolitan City Park, three evaluation methods were compared. In overall, three methods showed very similar results regardless of the computational costs and applicability, although the optimal parameters determined by the evaluations were different between the urban and forest images. There is no single measure that outperforms in the unsupervised evaluation. Any combinations of intra-segment measures (V, COV, WV) and inter-segment measures (MI, BSH, DTNP) provided almost the same results. Although supervised method may be biased by subjective selection of reference data, it can be easily applied to detect object of interest. The qualitative visual interpretation on the segmentation results corresponded with the unsupervised and supervised evaluations.

Smart Factory Policy Measures for Promoting Manufacturing Innovation (제조혁신 촉진을 위한 스마트공장 정책방안)

  • Park, Jaesung James;Kang, Jae Won
    • Korean small business review
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    • v.42 no.2
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    • pp.117-137
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    • 2020
  • We examine the current status of smart factory deployment and diffusion programs in Korea, and seek to promote manufacturing innovation from the perspective of SMEs. The main conclusions of this paper are as follows. First, without additional market creation and supply chain improvement, smart factories are unlikely to raise profitability leading to overinvestment. Second, new business models need to connect "manufacturing process efficiency" with "R&D" and "marketing" in value chain in smart factories. Third, when introducing smart factories, we need to focus on the areas where process-embedded technology is directly linked to corporate competitiveness. Based on the modularity-maturity matrix (Pisano and Shih, 2012) and the examples of U.S. Manufacturing Innovation Institute (MII), we establish the new smart factory deployment policy measures as follows. First, we shift our smart factory strategy from quantitative expansion to qualitative upgrading. Second, we promote by each sector the formation of industrial commons that help SMEs to jointly develop R&D, exchange standardized data and practices, and facilitate supplier-led procurement system. Third, to implement new technology and business models, we encourage partnerships, collaborations, and M&As between conventional SMEs and start-ups and business ventures. Fourth, the whole deployment process of smart factories is indexed in detail to identify the problems and provide appropriate solutions.

A Study on the Secondary Science Teachers' YouTuber Experience and Identity: Focusing on Foucault's Concept of Heterotopia (중등과학교사의 유튜버 경험과 정체성에 대한 연구 -푸코의 헤테로토피아 개념을 중심으로-)

  • Sein, Shin;Jun-Ki, Lee
    • Journal of The Korean Association For Science Education
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    • v.42 no.6
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    • pp.579-595
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    • 2022
  • This study is a qualitative case study of secondary science teachers who are doing educational activities in YouTube. In particular, this study attempts to interpret this case based on Foucault's concept of 'Heterotopia', which means a space that allows for private freedom or deviance by reflecting various utopias without the norms and constraints from every day or real space. Five secondary science teachers who voluntarily opened a personal channel on the YouTube platform and actively uploaded their own videos related to science education participated in the study. In order to understand the experiences of five secondary science teachers, data were individually collected through semi-structured in-depth interviews, and the collected data were analyzed using qualitative case study method. For valid interpretation of the study, we also referred to the video contents, teacher training materials, and teaching and learning materials produced by the participants. As a result of the study, seven themes were revealed: 'Desire for one's own unique educational activities,' 'Youtube as an extended classroom space,' 'Expanded network of relationships beyond the classroom barrier,' 'Satisfaction of desire for recognition and experience of identity as a YouTuber,' 'Tension between the educational space and the YouTube,' 'Space to be reborn as a craftsman,' and 'Finding one's own direction as a Teacher-YouTuber.' Given those findings, we found that the identity and desire of secondary science teachers, which were limited in the existing secondary schools and classrooms, was expanded in a new space called YouTube. In addition, we suggested that YouTube could be a space where science teachers can realize their own ideals and feel the joy. And simple regulating teacher's behavior in Youtube space only based on norms and standards shared in traditional educational space would rather hinder their healthy construction of identity and growth.

LRM's Characterics and Applications Plan Through Comparing with FRBR (FRBR과 비교를 통한 LRM의 특징 및 적용방안)

  • Lee, Mihwa
    • Journal of Korean Library and Information Science Society
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    • v.53 no.2
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    • pp.355-375
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    • 2022
  • This study is to grasp LRM's feature and applications plan to reflect LRM to cataloging related standards and individual system through comparing and analyzing LRM with the FR model in terms of entities, attributes, and relationships. The application plan is suggested as follows. First, the entity can be extended by defining sub-entities of each entity in the standards and the individual system in order to reflect LRM, even though entities such as families, groups, identifiers, authorized access points, concepts, objects, events, agency and rules have been deleted in LRM. Second, the attribute should be subdivided in the standards and the individual system in order to apply LRM, though many attributes have been changed to relationships for linked data and decreased in LRM. In particular, more specific and detailed property names in the standards and the individual system should be clearly presented, and the vocabulary encoding scheme corresponding to each property should be also developed, since properties with similar functions or repetition in various entities, and material specific properties are generalized and integrated into comprehensive property names. Third, the relationship should be extended through newly declaring the refinement or subtype of the relationship and considering a multi-level relationship, since the relationship itself is general and abstract under increasing the number of relationships in comparing to the property. This study will be practically utilized in cataloging related standards and individual system for applying LRM.

Solar and Interplanetary Observations and Models in Korea (국내 우주환경 자료 보유 현황: 태양·행성간 공간)

  • Oh, Suyeon;Lee, Jin-Yi;Division of Solar and Space Environment of KSSS,
    • Journal of Space Technology and Applications
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    • v.1 no.2
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    • pp.160-177
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    • 2021
  • The Solar and Space Environment Division of the Korean Space Science Society investigated the use and possession of ground and satellite observations and models of solar and planetary data operated by domestic research institutes and universities. Based on the findings, we would like to introduce observational instruments, data, and models in solar and interplanetary fields in this paper to improve understanding and use of each data and explore opportunities for interdisciplinary research. The ground and satellite observations, which require a lot of investment, were mainly held by research institutes (National Meteorological Satellite Center, Polar Research Institute, Korean Space Weather, Korea Astronomy and Space Science Institute and KAIST Satellite Research Institute), and model development was overwhelmingly carried out at Kyung Hee University. In solar and interplanetary fields, we introduce Fast Imaging Solar Spectrograph (FISS), neutron monitors, and the analysis models [for the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) and Hinode/X-Ray Telescope (XRT) observations] in nonequilibrium ionization state as representatives. Survey on solar and interplanetary fields can be downloaded from the website of the Korean Space Science Society (http://ksss.or.kr/). The paper makes know the importance of long-term and continuous management of space science-related materials, and hopes to contribute to enhancing the status of domestic space science data by utilizing locally produced data by various personnel participating in space science research.

Terrestrial Magnetospheric Observations and Models in Korea (국내 우주환경 자료 보유 현황: 자기권)

  • Park, Kyung Sun;Min, Kyungguk;Division of Solar and Space Environment of KSSS,
    • Journal of Space Technology and Applications
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    • v.1 no.2
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    • pp.178-198
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    • 2021
  • The Solar Space Environment Division of the Korean Society of Space Science (KSSS) has recently conducted a survey among the domestic researchers affiliated with academia, national research institutes, and for-profit institutes of how the data and models in their professional research field are produced, maintained, and utilized. The primary purpose of this survey is to increase the awareness and utilization of the space environment data and models as well as to promote constructive collaborations among the domestic and international researchers. The models and data surveyed are categorized into three sub-fields: the solar and interplanetary space, the (terrestrial) magnetosphere, and the ionosphere and upper atmosphere. The present paper reports the survey results in the "Magnetosphere" category. The survey shows that the domestically produced data in this category are far less than the data produced in other categories. This can be understood in part as follows: Magnetospheric research relies heavily on the in-situ observations but the development and operation of space-hardened satellites require a significant investment. Nevertheless, the recent publications show an increasing trend of research using the data from the ground stations and the recently launched domestic space missions. In the modeling front, there are first-principles physics models covering from the magnetospheric scale to the sub-ion scale and the models geared towards the space weather prediction. The detailed survey results can be accessed from the KSSS website (http://ksss.or.kr/).