• Journal of Korea Water Resources Association
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• v.55 no.1
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• pp.99-109
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• 2022

This study was intended to suggest the applicability of stepped boulder fishway using the concept of traditional boulder weir, focusing on the problems of existing concrete pool-and-weir fishways installed in mountain streams. To achieve this purpose, a stepped boulder fishway was designed and constructed as a pilot project in consideration of ascending capacity of the selected target fishes. Under the given discharge conditions, the hydraulic characteristics of the fishway were investigated in the field, and the characteristics and ascending capacity of the fishes were compared and analyzed. The fishway had a short length and steep slope, but the mean drops between each baffle were the range of 0.15 to 0.29 m, and this range satisfied the limit condition of about 0.40 m, which was in the limit of the drop that target fishes can ascend. The mean velocities of each baffle and pool were 0.82 to 0.87 m/sec and 0.13 to 0.24 m/sec. This result satisfied the conditions of burst speed (10 to 30 times of body length) and mean velocity of the resting pool (7 to 25% of burst speed) for target fishes. Since the bottom surface of the pool formed of boulders had a gentle reverse slope and rotational flow did not occur, the efficiency of fishway can be increased, and it will also be possible to solve the maintenance problem by flushing bed materials.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.227-238
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• 2022

This study is the case of non-face-to-face teaching-learning in the subject of "Research and Guidance on Early Childhood Materials" in the pre-child teacher training program. The study conducted a non-face-to-face teaching-learning model for 18 students at B University in region C who took lectures on 'Research and Guidance on Early Childhood Materials' in the first semester of 2021. As a non-face-to-face teaching-learning model, it consisted of video lectures, real-time zoom classes, and various forms of 'communication' through frequent feedback and interaction and 'participation'. As a teaching-learning strategy for the participation of pre-service early childhood teachers, comment on questions related to early childhood materials, in-depth reflection on early childhood materials through writing reflective journals and observation reports, and step-by-step presentation of making childhood materials plans, processes, and results were carried out. As a result of exploring the experience of making early childhood materials for pre-service early childhood teachers, factors such as "growth experience through trial and error," "thinking from child's point of view", "Increase efficiency and reduce burden through communication", "Process rather than result" and "The importance of communication and interaction in non-face-to-face classes"

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.459-466
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• 2021

The present study was conducted to propose future research directions for weed management by examining the current trends of research on weed occurrence according to cropping systems. The cropping systems are developed for the efficient use of arable land, and the weed flora changes according to the management practices of a given cropping system. In particular, weed occurrence can be reduced by altering the soil environment. In addition, cultivation methods, such as tillage, affect the weed seed bank in the soil, thus altering the pattern of weed occurrence. Here, we propose three weed management practices according to the cropping system. First, it is necessary to develop a model that can classify weed species by analyzing young seedlings and can predict the flora in the field. Second, it is important to manage the cropping system history and establish a database of agricultural information, which can be linked to meteorological and geographic data. Third, it is critical to estimate the weed occurrence and soil seed bank dynamics, based on which a cropping system platform and digitalization technology can be developed. In the future, the prediction of weed occurrence and control according to the cropping system will contribute to sustainable agriculture by reducing the use of herbicides and solving the problems of resistant weeds.

• Membrane Journal
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• v.31 no.6
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• pp.417-425
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• 2021

As the demand for high-capacity batteries increases, there has been growing researches on the lithium metal anode with a capacity (3,860 mAh/g) of higher than that of conventional one and a low electrochemical potential (-3.040 V). In this study, using the anatase phased TiO₂ nanoparticles synthesized by hydrothermal synthesis, a PVdF-HFP/TiO₂ organic/inorganic composite material was designed and used as an interfacial protective layer for a Li metal anode. As-formed organic/inorganic-lithium composite thin film was confirmed through the crystalline structure and morphological analyses. In addition, the electrochemical test (cycle stability and voltage profile) confirmed that the protective layer of PVdF-HFP/TiO₂ composite (10 wt% TiO₂ and 1.1 ㎛ film thickness) contributed to the enhanced electrochemical performance of the lithium metal anode (Colombic efficiency retention: 90% for 77 cycles). Based on comparative test with the untreated lithium electrode, it was confirmed that our protective layer plays an important role to stabilize/improve the EC performance of the lithium metal negative electrode.

• Journal of Digital Convergence
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• v.20 no.4
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• pp.367-376
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• 2022

In traditional criminal cases, there is a limit to information collection because information on the subject of investigation is provided only with personal information held by the national organization of legal. Surface web-based OSINT(Open Source Intelligence), including SNS and portal sites that can be searched by general search engines, can be used for meaningful profiling for criminal investigations. The Korean-style OSINT workflow can effectively profile based on OSINT, but in the case of individuals, OSINT that can be collected is limited because it begins with "name", and the reliability is limited, such as collecting information of the persons with the same name. In order to overcome these limitations, this paper defines information related to individuals, i.e., equivalent information, and enables efficient and accurate information collection based on this. Therefore, we present an improved workflow that can extract information related to a specific person, ie., equivalent information, from OSINT. For this purpose, different workflows are presented according to the person's profile. Through this, effective profiling of a person (individuals) is possible, thereby increasing reliability in collecting investigation information. According to this study, in the future, by developing a system that can automate the analysis process of information collected using artificial intelligence technology, it can lay the foundation for the use of OSINT in criminal investigations and contribute to diversification of investigation methods.

• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.73-84
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• 2021

Recently, interest in environmental issues is increasing worldwide due to abnormal climate phenomena caused by global warming. Global efforts are continuing to actively respond to climate change, but the dependence on fossil fuels is still high. In particular, a huge amount of fossil fuels and mineral resources are buried in the Arctic Circle, so development and construction projects are being actively pursued. Participation and cooperation in the development of Arctic resources (oil and gas resources) is one of the alternatives to domestic energy supply. Resource development in the Arctic Circle requires close review(Poor development environment and technical limitations due to extreme climate, environmental problems due to resource development, social impact, etc.) in advance compared to general resource development. In this pater, the laws and guidelines related to climate change to be considered were reviewed. when developing Arctic resources. In addition, the countermeasures against climate change applied in large-scale resource development projects in the Arctic were reviewed. It is expected that the results of the research and analysis of this study will be used to establish strategies to respond to new risk factors that influence the successful promotion and operation of the Arctic region resource development project.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.7
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• pp.471-478
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• 2022

This paper is about research and development of Korea Aerospace University's Solar-Powered UAV System that named of KAU-SPUAV, and describes the design process of the 4.2 m solar UAV that succeeded in a long flight of 32 hours and 19 minutes at June 2020. In order to improve the long-term flight performance of the KAU-SPUAV, For reduce drag, a circular cross-section of the fuselage was designed, and manufactured light and sturdy fuselage by applying a monocoque structure using a glass fiber composite material. In addition, a solar module optimized for the wing shape of a 4.2 m solar drone was constructed and arranged, and a propulsion system applied with the 23[in] × 23[in] propeller was constructed to improve charging and flight efficiency. The developed KAU-SPUAV consumes an average of 55W when cruising and can receive up to 165W of energy during the day, and its Long-term Endurance was verified through flight tests.

• Journal of the Korea Society of Computer and Information
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• v.27 no.3
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• pp.137-147
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• 2022

Diagnosis and management of skin condition is a very basic and important function in performing its role for workers in the beauty industry and cosmetics industry. For accurate skin condition diagnosis and management, it is necessary to understand the skin condition and needs of customers. In this paper, we developed SCIS, a big data-based skin care information system that supports skin condition diagnosis and management using social media big data for skin condition diagnosis and management. By using the developed system, it is possible to analyze and extract core information for skin condition diagnosis and management based on text information. The skin care information system SCIS developed in this paper consists of big data collection stage, text preprocessing stage, image preprocessing stage, and text word analysis stage. SCIS collected big data necessary for skin diagnosis and management, and extracted key words and topics from text information through simple frequency analysis, relative frequency analysis, co-occurrence analysis, and correlation analysis of key words. In addition, by analyzing the extracted key words and information and performing various visualization processes such as scatter plot, NetworkX, t-SNE, and clustering, it can be used efficiently in diagnosing and managing skin conditions.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.107-123
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• 2021

In recent years, due to the continuous density and urbanization of space, the expansion of awareness of rights, the need for landscape conservation, and the development of construction technology, the conventional flat land use has been deviated from the conventional flat land use, and the transmission line, urban railway, parking lot, communal district, underground shopping mall, pipeline, etc. Although 3D spatial activities are carried out in the form of 3D space, there are considerable difficulties in administration to manage the 3D use of land due to the inadequacy of related regulations. In this background, for the administration that can manage Sectional Superficies, which is a representative case of 3D spatial use of parcels, which is a registered unit of land, first, the law on the establishment and management of spatial information, and cadastral re-examination from the legal and institutional aspects Standardization of 3D space registration through amendments to the Special Act, etc. and the formation of consensus among related departments. Second, in technical and administrative aspects, the registration of Sectional Superficies based on cadastral survey results, establishment of a platform for integrated management of location and attribute data, and registration method was found to be in need of improvement. As suggested in this study, by registering and managing Sectional Superficies, it is possible to manage various 3D land use of not only ground space or surface space but also underground space. It is expected to be able to register and manage lot-based 3D land use efficiently.

• Journal of Life Science
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• v.32 no.4
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• pp.279-284
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• 2022

This study was conducted to establish a genetic evaluation system applicable to general farms for improving cows raised on farms. The analysis used Best Linear Unbiased Prediction (BLUP) and Genomic Best Linear Unbiased Prediction (GBLUP) for 619 cows raised in Gyeonggi-do Province and compared and analyzed the accuracy of the estimated breeding value according to four traits (carcass weight, loineye muscle area, back fat thickness, and marbling). In the case of the GBLUP method, the size of the reference population was divided into different four groups and analyzed. The analysis results confirmed that the accuracy of the breeding value of each trait increased as the size of the GBLUP reference population increased. Comparing the accuracy of the breeding values estimated using the BLUP and GBLUP methods, it was confirmed that when the breeding values were estimated using the GBLUP method, they increased by 0.10, 0.09, 0.09, and 0.11 for carcass weight, eye muscle area, back fat thickness, and marbling scores, respectively. Applying the GBLUP method to the evaluation and selection of cows can enable precise and accurate individual selection, while increasing the size of the reference population can make even more accurate individual selection possible, thus increasing selection efficiency.