• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.587-596
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• 2022

Sea levels are rising as a result of climate change, and low-lying areas along the coast are at risk of flooding. Therefore, we tried to investigate the relationship between sea level change and climate indices using satellite altimeter data (Topex/Poseidon, Jason-1/2/3) and southern oscillation index (SOI) and the Pacific decadal oscillation (PDO) data. If time domain data were converted to frequency domain, the original data can be analyzed in terms of the periodic components. Fourier transform and Wavelet transform are representative periodic analysis methods. Fourier transform can provide only the periodic signals, whereas wavelet transform can obtain both the periodic signals and their corresponding time location. The cross-wavelet transformation and the wavelet coherence are ideal for analyzing the common periods, correlation and phase difference for two time domain datasets. Our cross-wavelet transform analysis shows that two climate indices (SOI, PDO) and sea level height was a significant in 1-year period. PDO and sea level height were anti-phase. Also, our wavelet coherence analysis reveals when sea level height and climate indices were correlated in short (less than one year) and long periods, which did not appear in the cross wavelet transform. The two wavelet analyses provide the frequency domains of two different time domain datasets but also characterize the periodic components and relative phase difference. Therefore, our research results demonstrates that the wavelet analyses are useful to analyze the periodic component of climatic data and monitor the various oceanic phenomena that are difficult to find in time series analysis.

• Journal of Korean Society for Quality Management
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• v.50 no.4
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• pp.647-664
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• 2022

Purpose: The purpose of this study is to derive major policies that domestic small and medium-sized manufacturing companies should consider to maximize productivity and quality improvement by utilizing manufacturing data and AI, and to find priorities and implications. Methods: In this study, domestic and international issues and literature review by country were conducted to derive major considerations such as manufacturing AI technology, manufacturing AI talent, manufacturing AI data and manufacturing AI ecosystem. Additionally, the questionnaire survey targeting 46 experts of manufacturing data and AI industry were conducted. Finally, the major considerations and detailed factors importance were derived by applying the Analytic Hierarchy Process (AHP). Results: As a result of the study, it was found that 'manufacturing AI technology', 'manufacturing AI talent', 'manufacturing AI data', and 'manufacturing AI ecosystem' exist as key considerations for domestic manufacturing AI. After empirical analysis, the importance of the four key considerations was found to be 'manufacturing AI ecosystem (0.272)', 'manufacturing AI data (0.265)', 'manufacturing AI technology (0.233)', and 'manufacturing AI talent (0.230)'. The importance of the derived four viewpoints is maintained at a similar level. In addition, looking at the detailed variables with the highest importance for each of the four perspectives, 'Best Practice', 'manufacturing data quality management regime, 'manufacturing data collection infrastructure', and 'manufacturing AI manpower level of solution providers' were found. Conclusion: For the sustainable growth of the domestic manufacturing AI ecosystem, it should be possible to develop and promote manufacturing AI policies in a balanced way by considering all four derived viewpoints. This paper is expected to be used as an effective guideline when developing policies for upgrading manufacturing through domestic manufacturing data and AI in the future.

• Journal of the Korean Society for information Management
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• v.40 no.2
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• pp.211-241
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• 2023

With rapidly changing technological implementation of operating systems of businesses, the Ministry of foreign affairs (MOFA) of the Republic of Korea (ROK) has been undergoing digital transformation to its overall operations with the intent to innovate information and knowledge management (IKM) strategies since the mid-2000s. However, assessment as to the effectiveness of implemented IKM has been inadequately analyzed. This study aims to assess the concepts and limitations of the MOFA's current IKM strategies and the methods it employs to deliver its IKM framework, in light of strengthening the organizational ambidexterity and absorptive capacity, and also fostering organizational innovation through a qualitative study that involves interviews and analysis of reports from MOFA. The MOFA's IKM possesses dynamic capabilities to adapt to changing digital technologies. However, the institution's IKM is constrained by limitations associated with the utilization of the IKM system such as a structure that handles confidential documents and a lack of a collaborative system for IKM, and external limitations such as changes in the domestic political situation governing MOFA's priorities and the hierarchy of government organizations. Consequently, developing the organizational ambidexterity and absorptive capacity was not possible. To develop an IKM framework for organizational innovation, the MOFA must devise a way to minimize the impact of external changes by overcoming internal limitations. To that end, a detailed study on the development of a practically usable IKM system should include establishing a dialogue between job groups and enhancing employee competency in preparation for a changing environment.

• Journal of Service Research and Studies
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• v.11 no.1
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• pp.21-30
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• 2021

This study examined methodologies for establishing a customer experience-focused innovation strategy, which is essential to transforming existing collection and preservation-oriented museum service into a visitor-oriented service. To this end, a review of studies examining good customer experience and bad customer experience was conducted, focusing on change in museum environments and customer experience from the service science and customer experience management perspectives. Research was conducted to present and prove. Implementing a customer experience-oriented innovation strategy in a museum requires exploring the various approaches that can be used to reach the target state from the present state, focusing on the customer, and selecting the most appropriate transformation plan. This study found that effective approaches are distinguished by the fact that they generate positive emotions in customers and use customer experience data to make important decisions regarding the establishment of practical resources in museums. This innovation model was developed and validated by analyzing how it differed from existing evaluation methods. Finally, a regression analysis using the customer experience measurement procedure, customer experience diagnosis/evaluation, customer experience innovation strategy, and museum performance as variables revealed a significant causal relationship.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.1
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• pp.153-166
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• 2024

The digitalization of tasks for smart construction requires the smooth exchange of digital data among stakeholders to be effective, but there is a lack of digital data standardization and utilization methods. This paper proposes a digital construction information structure to transform information from road construction sites into digital formats. The study targets include significant tasks, such as work planning, scheduling, safety management, and quality control. The key to the construction information structure is separating construction information into objects and activities, defining unit works by combining these two types of information to ensure flexibility in representing and modifying construction information. The objects and activities have their respective hierarchical structures, which are defined flexibly to match the actual content. This structure achieves both efficiency and detail. The pilot structure was applied to highway construction projects and implemented digitally using general formats. This study enables the digitalization of road construction processes that closely resemble reality, accelerating the digital transformation of the civil engineering industry by developing a digital twin of the entire road construction lifecycle.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.37 no.1
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• pp.1-16
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• 2024

Objectives : We aimed to study the effect of Smilax China L.(SCL), which has anti-inflammatory, antioxidant, and anticancer effects, on the growth of skin cancer cells. Methods : HaCaT cells, a normal human cell line, and skin cancer cells including A431, SK-MEL-5 and SK-MEL-28 cells were treated with Smilax China L. ethanol extract(SCL-EtOH) at concentrations of 5, 10, 20 and 40㎍/㎖. Meanwhile, JB6 Cl41, a normal mouse epithelial cell line, was treated with epidermal growth factor(EGF) and phorbol 12-myristate 13-acetate(TPA), an inflammatory factor, to induce cell transformation and treated with SCL-EtOH. In addition, we treated SK-MEL-5 and SK-MEL-28 cells with SCL-EtOH at various concentrations and checked the effect on the cell cycle. Results : As a result, it showed no toxicity to HaCaT cells up to the highest concentration of 40㎍/㎖, and significant cell growth inhibition to A431, SK-MEL-5 and SK-MEL-28 cells in a time- and concentration-dependent manner. In addition, as a result of checking the shape of skin cancer cells according to SCL-EtOH treatment, it was observed that as the concentration increased, the number of normally attached and growing cells decreased and the shape of the cells changed. Colony formation was significantly reduced in a concentration-dependent manner in JB6 Cl41 cells treated with EGF or TPA. Flow cytometry analysis with propidium iodide(PI) staining showed that SCL-EtOH induced the G2/M phase arrest. We further confirmed the decrease in Cyclin B1 expression and increase in p27 expression associated with the G2/M phase of the cell cycle through western blot analysis. Flow cytometry analysis confirmed that SCL-EtOH induced cell apoptosis. Furthermore, through Western blot analysis, it was observed that the expression of cleaved-caspase-7, which is related to apoptosis, increased. Finally, it was confirmed that the expression of COX-2, an inflammatory marker protein, decreased in a concentration-dependent manner with SCL-EtOH. Conclusions : Through the above results, we have established a basis for applying SCL to the treatment of skin cancer.

• Korean Chemical Engineering Research
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• v.62 no.1
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• pp.105-111
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• 2024

The SLA (Stereolithography Apparatus) method is a type of 3D printing technique predicated on the transformation of liquid photocurable resin into a solid form through UV laser exposure, and its application is increasing in various fields. In this study, we conducted research to enhance the hydrophobicity and transparency of SLA 3D printing surfaces for microfluidic system production. The enhancement of surface hydrophobicity in SLA outputs was attainable through the application of hydrophobic coating methods, but the coating durability under different conditions varied depending on the type of hydrophobic coating. Additionally, to simultaneously achieve the required transparency and hydrophobic properties for the fabrication of microfluidic systems, we applied hydrophobic coatings to the proposed transparency enhancement method from prior research and compared the changes in contact angles. Teflon coating was proposed as a suitable hydrophobic coating method for the fabrication of microfluidic systems, given its excellent transparency and high coating durability in various environmental conditions, in comparison to titanium dioxide coating. Finally, we produced an Electrophoresis of Charged Droplet (ECD) chip, one of the digital microfluidics systems, using SLA 3D printing with the proposed Teflon coating method (Fluoropel 800). Droplet manipulation was successfully demonstrated with the fabricated chip, confirming the potential application of SLA 3D printing technology in the production of microfluidic systems.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.34 no.1
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• pp.129-141
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• 2024

Amidst the acceleration of digital transformation across various sectors, the financial market is increasingly focusing on the development of digital and electronic payment methods, including currency. Among these, Central Bank Digital Currencies (CBDC) are emerging as future digital currencies that could replace physical cash. They are stable, not subject to value fluctuation, and can be exchanged one-to-one with existing physical currencies. Recently, both domestic and international efforts are underway in researching and developing CBDCs. However, current CBDC systems face scalability issues such as delays in processing large transactions, response times, and network congestion. To build a universal CBDC system, it is crucial to resolve these scalability issues, including the low throughput and network overload problems inherent in existing blockchain technologies. Therefore, this study proposes a solution based on reinforcement learning for handling large-scale data in a CBDC environment, aiming to improve throughput and reduce network congestion. The proposed technology can increase throughput by more than 64 times and reduce network congestion by over 20% compared to existing systems.

• Journal of Digestive Cancer Research
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• v.9 no.1
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• pp.1-7
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• 2021

The length, the frequency, and the methods of surveillance for intraductal papillary mucinous neoplasm (IPMN) of the pancreas are still debating. According to the recent guidelines, IPMN is stratified into "high-risk stigmata" or absolute indication and "worrisome features" or relative indication as a guide in managing these patients, either those with resection of the lesion or those under surveillance. The risk of malignant transformation was quite low for branch duct-IPMNs without worrisome features or high risk stigmata. However, because the incidence rate of pancreatic cancer in these patients increase linearly with time, continued long-term surveillance is therefore important for patients with low-risk, as well as higher-risk, IPMN. Considering the high prevalence of malignancy, main duct-IPMN should be treated by surgical resection. Among patients with these type IPMNs, segmental dilatation of the main pancreatic duct without any mural nodules and larger than 10 mm of main pancreatic duct might not be immediately resected and need very careful examination and observation. The risk related to a major pancreatic resection must balance the risk of surveillance in patients with IPMN of the pancreas who have co-morbidity and are elderly.

• The Mathematical Education
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• v.63 no.3
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• pp.393-409
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• 2024

The number line model, which intuitively marks numerical magnitudes in space, is widely utilized to help in understanding the magnitudes that fractions and decimals represent. The study analyzed 6^th graders' understanding of fractions and decimals, their problem solving strategies, and whether individual differences in the flexibility of various strategy uses are associated with the accuracy of numerical representation, calculation fluency, and overall mathematical achievement. As a result of the study, students showed relatively lower accuracy in representing fractions and decimals on a number line compared to natural numbers, especially for fractions with odd denominators compared to even denominators, and for two-digit decimals compared to three-digit decimals. Regarding strategy use, students primarily used benchmark, segmentation, and approximation strategies for fractions, and benchmark, rounding, and transformation strategies for decimals sequentially. Lastly, as students used various representation strategies for fractions, their accuracy in representing fractions and their overall mathematical achievement scores showed significantly better outcomes. Taken together, we suggest the need for careful instruction on different interpretations of fractions, the place value of decimals, and the meaning of zero in decimal places. Moreover, we discuss instructional methods that integrate the number line model and its diverse representation strategies to enhance students' understanding of fractions and decimals.