• Journal of Soil and Groundwater Environment
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• v.28 no.spc
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• pp.18-39
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• 2023

Rapid development of geophysical exploration and hydrogeologic monitoring techniques has yielded remarkable increase of datasets related to groundwater systems. Increased number of datasets contribute to understanding of general aquifer characteristics such as groundwater yield and flow, but understanding of complex heterogenous aquifers system is still a challenging task. Recently, applications of data science technique have become popular in the fields of geophysical explorations and monitoring, and such attempts are also extended in the groundwater field. This work reviewed current status and advancement in utilization of data science in groundwater field. The application of data science techniques facilitates effective and realistic analyses of aquifer system, and allows accurate prediction of aquifer system change in response to extreme climate events. Due to such benefits, data science techniques have become an effective tool to establish more sustainable groundwater management systems. It is expected that the techniques will further strengthen the theoretical framework in groundwater management to cope with upcoming challenges and limitations.

• Journal of Korean Society for Quality Management
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• v.51 no.3
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• pp.461-479
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• 2023

Purpose: It emphasizes the importance of cost analysis for weapons systems that require enormous develop- ment costs, analyzes the problems of cost analysis steps from a practical point of view, and presents the direction of business development in terms of cost analysis reliability, timeliness, and efficiency. Methods: It analyzes the R&D cost of Micro satellites with a complex cost structure and large scale according to engineering estimation procedures, derives major analysis step-by-step problems, and presents business development directions. Results: Problems with standards and assumptions, data collection, cost division structure, and cost estimation methods were derived through the micro satellite cost analysis process, and business development directions such as expanding common standards, standardizing basic data, standardizing cost division structures and cost items, and data asset were presented. Conclusion: In order to develop work in terms of cost analysis reliability, timeliness, and efficiency, it is important to prepare and standardize standards and rules for detailed tasks at each analysis stage, and through this, it is expected that high utilization value and systematic cost data will be assetized in the future.

• Journal of Society of Preventive Korean Medicine
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• v.28 no.1
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• pp.59-67
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• 2024

Objectives : This study aims to systematically examine the determinants of the intention to take herbal medicine among individuals with experience in Korean medicine. Methods : This study utilized the 3,245 respondents from the 2020 Korean Medicine Utilization and Herbal Medicine Consumption Survey who reported having used Korean medical services; the responses were selected through a complex sample analysis, and analytics techniques including frequency analysis, Rao-scott chisquare test, and logistic regression were used to analyze the responses. Results : The results of data analysis reveal that the intention to take herbal medicine in the future among these individuals was significantly influenced by factors such as enrollment in private health insurance, the facility environment of Korean medical institutions, and treatment outcomes. Conclusions : Therefore, it is imperative for Korean medical institutions to continuously try reasonable action strategies, including improving medical facilities/environments and building institutional mechanisms among medical staff and members to enhance the quality of Korean medical services. Additionally, the Ministry of Health and Welfare needs to make policy efforts to reduce patients' medical expenses, such as reducing the co-insurance rate in the pilot project of applying health insurance to herbal medicine.

• International Journal of Computer Science & Network Security
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• v.24 no.4
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• pp.11-25
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• 2024

The proliferation of IoT devices has presented an unprecedented challenge in managing device identities securely and efficiently. In this paper, we introduce an innovative Hybrid Blockchain-Based Approach for IoT Identity Management that prioritizes both security and efficiency. Our hybrid solution, strategically combines the advantages of direct and indirect connections, yielding exceptional performance. This approach delivers reduced latency, optimized network utilization, and energy efficiency by leveraging local cluster interactions for routine tasks while resorting to indirect blockchain connections for critical processes. This paper presents a comprehensive solution to the complex challenges associated with IoT identity management. Our Hybrid Blockchain-Based Approach sets a new benchmark for secure and efficient identity management within IoT ecosystems, arising from the synergy between direct and indirect connections. This serves as a foundational framework for future endeavors, including optimization strategies, scalability enhancements, and the integration of advanced encryption methodologies. In conclusion, this paper underscores the importance of tailored strategies in shaping the future of IoT identity management through innovative blockchain integration.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4465-4471
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• 2023

Hands-on education and training is a key part of fixing and developing technology knowledge and is an inherent part of many engineering and scientific curricula. However, access to large complex training facilities, such as nuclear reactor, could be limited by various factors, such as unavailability of those facilities in the region, high traveling costs or harmonization of the schedules of hands-on E&T with theoretical lectures and with the operational schedule of the facility. To handle the issue, several success stories have been reached with the introduction of the Internet Reactor Labs (IRL). The Internet Reactor Labs can strongly contribute to accessibility of training at research reactors and can contribute to improvements in their utilization. The paper describes the development of the Internet Reactor Lab at the VR-1 reactor of the Czech Technical University in Prague. Contrary to single-purpose IRLs, it presents various modalities of online teaching and training in experimental reactor physics and reactor operation in general as well as outreach activities that have been developed in recent years.

• Journal of Astronomy and Space Sciences
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• v.41 no.2
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• pp.79-85
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• 2024

Nowadays, the trend in lunar exploration missions is shifting from prospecting lunar surface to utilizing in-situ resources and establishing sustainable bridgehead. In the past, experiments were mainly focused on rover maneuvers and equipment operations. But the current shift in trend requires more complex experiments that includes preparations for resource extraction, space construction and even space agriculture. To achieve that, the experiment requires a sophisticated simulation of the lunar environment, but we are not yet prepared for this. Particularly, in the case of lunar regolith simulants, precise physical and chemical composition with a rapid development speed rate that allows different terrains to be simulated is required. However, existing lunar regolith simulants, designed for 20th-century exploration paradigms, are not sufficient to meet the requirements of modern space exploration. In order to prepare for the latest trends in space exploration, it is necessary to innovate the methodology for producing simulants. In this study, the basic framework for lunar regolith simulant development was established to realize this goal. The framework not only has a sample database and a database of potential simulation target compositions, but also has a built-in function to automatically calculate the optimal material mixing ratio through the particle swarm optimization algorithm to reproduce the target simulation, enabling fast and accurate simulant development. Using this framework, we anticipate a more agile response to the evolving needs toward simulants for space exploration.

• Journal of Powder Materials
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• v.31 no.3
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• pp.213-219
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• 2024

Additive Manufacturing (AM) is a process that fabricates products by manufacturing materials according to a three-dimensional model. It has recently gained attention due to its environmental advantages, including reduced energy consumption and high material utilization rates. However, controlling defects such as melting issues and residual stress, which can occur during metal additive manufacturing, poses a challenge. The trial-and-error verification of these defects is both time-consuming and costly. Consequently, efforts have been made to develop phenomenological models that understand the influence of process variables on defects, and mechanical/ electrical/thermal properties of geometrically complex products. This paper introduces modeling techniques that can simulate the powder additive manufacturing process. The focus is on representative metal additive manufacturing processes such as Powder Bed Fusion (PBF), Direct Energy Deposition (DED), and Binder Jetting (BJ) method. To calculate thermal-stress history and the resulting deformations, modeling techniques based on Finite Element Method (FEM) are generally utilized. For simulating the movements and packing behavior of powders during powder classification, modeling techniques based on Discrete Element Method (DEM) are employed. Additionally, to simulate sintering and microstructural changes, techniques such as Monte Carlo (MC), Molecular Dynamics (MD), and Phase Field Modeling (PFM) are predominantly used.

• Korean Circulation Journal
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• v.52 no.7
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• pp.485-495
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• 2022

Coronary artery disease is highly prevalent in chronic kidney disease (CKD) and is a risk factor for contrast-associated acute kidney injury (CA-AKI), a complication of cardiovascular procedures that require contrast administration (e.g., coronary angiography, percutaneous coronary intervention [PCI]). CA-AKI has a major impact on morbidity, mortality, and healthcare resource utilization. The incidence of CA-AKI is particularly high in patients with pre-existing CKD, advanced age and comorbidities that increase the likelihood of CKD. The focus of the present review is to provide a brief overview on the assessment of the risk for and prevention of CA-AKI in patients undergoing angiography and PCI, including recognition of the important patient- and procedure-related factors that may contribute to CA-AKI. Preventive and treatment strategies, the mainstay of which is volume repletion by normal saline, are briefly discussed. The main focus of the review is placed on technical details of contrast minimization techniques, including ultra-low contrast angiography and zerocontrast PCI. Operator competence in such techniques is important to ensure that procedural challenges in patients with CKD, like vessel calcification, multivessel disease and complex anatomical subsets, are effectively addressed by PCI while minimizing the risk of CA-AKI.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.5
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• pp.558-566
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• 2024

This study proposes method for enhancing the performance of previously developed or produced weapon systems without developing new detection equipment by using Phase Gradient Metasurfaces(PGMS). Metasurface has been studied and utilized a lot to improve the detection performance of inorganic systems, but its utilization is low due to its narrow bandwidth and complex structure. To address some of these limitations, dual-band power focusing PGMS is proposed. Its frequency independent unit cell characteristic enables creating metasurface that concentrates signals in dual-band. The designed PGMS was validated through near-field and far-field measurement, confirming signal concentration at the specified focal length and improved gain in the dual bands.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.490-499
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• 2017

In recent years, the introduction of complex systems analysis based on various variables has become more active in order to identify and analyze complex problems of Modern Society. Prediction of patients' spatial perception and usability according to the spatial arrangement of the outpatient department is a very important factor for providing high quality hospital service. For objective analysis, the standard program procedure and analysis index for the diseases of the elderly were prepared and the uniformity of the atmospheric space was evaluated through heat map analysis and quantitative analysis. In this study, 73 cells were installed and simulated to analyze the uniformity of the four alternatives according to the change of the arrangement of the medical care space, receiving space, and consultation space using the complex system analysis method for the nursing hospitals. The resulting density was derived. The results are as follows. 1)The layout of the reception space has the greatest influence on the total spatial density of the waiting space. 2) The uniformity of the waiting space can be increased by separating the examination space and the examination space. 3)The closer the location of the receiving space is from the entrance, the greater the density of the waiting space. Finally, this study applied discrete event simulation to the evaluation of uniformity of atmosphere space, and proved that the actor - based model can be utilized for utilization and evaluation as spatial analysis methodology.