• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.393-399
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• 2020

Saposhnikoviae Radix (SR) and Peucedani Japonici Radix (PR) have been used as the main traditional herbal medicines in Korea, China and Japan. In this study, ultra-performance liquid chromatography coupled to quadrupole time of flight mass spectrometry (UPLC-QTOF/MS)-based metabolomics was applied to evaluate the quality of SR and PR using the marker compounds. In the S-plot of SR and PR, 5-O-methylvisammioside and peucedanol were selected as a marker compound for SR and PR, respectively. Also, an UPLC method was established and well validated for marker compounds of SR and PR. These results suggested that the established analysis method could be used one of the good methods for the classification and quality assessment of SR and PR.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.543-550
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• 2023

Mulberry fruit is a superior source of polyphenols, especially anthocyanin, and has a long history of use as an edible fruit and traditional medicine. The anthocyanin composition of mulberry fruit from 15 Korean cultivars was analyzed by ultra-performance liquid chromatography diode array detector with quadrupole time of flight/mass spectrometry (UPLC-DAD-QToF/MS) based on a cyanin internal standard. The four glycosides were identified by comparison with authentic standards and published reports. The major anthocyanin was cyanidin 3-O-glucoside (71.7%), followed by cyanidin 3-O-rutinoside (26.6%). The minor components (total of 1.7%) were pelargonidin 3-O-glucoside and pelargonidin 3-O-rutinoside. The total anthocyanin content (mg/100 g, dry weight) of mulberry fruit varied by cultivar and ranged from 471.5±4.0 (Su Hong) to 4,700.2±54.0 (Gwa Sang2). Among the 15 cultivars examined, Gwa Sang2 showed the highest level of cyanidin 3-O-glucoside (3,133.4±32.6), which was 9-fold higher than that of Su Hong (351.5±3.4). In conclusion, anthocyanin profiles, including pelargonidin 3-O-glucoside and pelargonidin 3-O-rutinoside, were reported for the first time from 15 Korean mulberry fruit cultivars. The results will contribute valuable information on pharmaceutical properties, breeding superior mulberry cultivars, and food industries.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.3
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• pp.41-47
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• 2024

With the advancement and proliferation of the Internet of Things (IoT), a wide range of location-based services are being offered, and various ranging methods are being researched to meet the objectives of the required services. Conventional ranging methods involve the direct exchange of signals between tags and anchors to estimate distance, presenting a limitation in efficiently utilizing communication resources in large-scale IoT environments. To overcome these limitations, active-passive ranging methods have been proposed. However, there is a lack of theoretical convergence guarantees against clock drift errors and a detailed analysis of the characteristics of ranging estimation techniques, making it challenging to derive precise positioning results. In this paper, an improved active-passive ranging method that accounts for clock drift errors is proposed for precise positioning in large-scale IoT environments. The simulation results confirmed that the proposed active-passive ranging method can enhance distance estimation performance by up to 94.4% and 14.4%, respectively, compared to the existing active-passive ranging methods.

• Korean Journal of Remote Sensing
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• v.40 no.3
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• pp.257-268
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• 2024

Drone-mounted hyperspectral sensors (DHSs) have revolutionized remote sensing in agriculture by offering a cost-effective and flexible platform for high-resolution spectral data acquisition. Their ability to capture data at low altitudes minimizes atmospheric interference, enhancing their utility in agricultural monitoring and management. This study focused on addressing the challenges of radiometric and geometric distortions in preprocessing drone-acquired hyperspectral data. Radiometric correction, using the empirical line method (ELM) and spectral reference panels, effectively removed sensor noise and variations in solar irradiance, resulting in accurate surface reflectance values. Notably, the ELM correction improved reflectance for measured reference panels by 5-55%, resulting in a more uniform spectral profile across wavelengths, further validated by high correlations (0.97-0.99), despite minor deviations observed at specific wavelengths for some reflectors. Geometric correction, utilizing a rubber sheet transformation with ground control points, successfully rectified distortions caused by sensor orientation and flight path variations, ensuring accurate spatial representation within the image. The effectiveness of geometric correction was assessed using root mean square error(RMSE) analysis, revealing minimal errors in both east-west(0.00 to 0.081 m) and north-south directions(0.00 to 0.076 m).The overall position RMSE of 0.031 meters across 100 points demonstrates high geometric accuracy, exceeding industry standards. Additionally, image mosaicking was performed to create a comprehensive representation of the study area. These results demonstrate the effectiveness of the applied preprocessing techniques and highlight the potential of DHSs for precise crop health monitoring and management in smart agriculture. However, further research is needed to address challenges related to data dimensionality, sensor calibration, and reference data availability, as well as exploring alternative correction methods and evaluating their performance in diverse environmental conditions to enhance the robustness and applicability of hyperspectral data processing in agriculture.

• Journal of Applied Biological Chemistry
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• v.64 no.2
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• pp.113-119
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• 2021

Olive (Olea europaea L.) leaves, a raw material for health functional foods and cosmetics have abundant polyphenols including oleuropein (major bioactive compound) with various biological activities: antioxidant, antibacterial, antiviral, anticancer activity, and inhibit platelet activation. Oleuropein has been reported as skin protectant, antioxidant, anti-ageing, anti-cancer, anti-inflammation, anti-atherogenic, anti-viral, and anti-microbial activity. Despite oleuropein is the important compound in olive leaves, there is still no quantitative approach to reveal oleuropein content in commercial products. Therefore, a validated method of analysis has to develop for oleuropein. In this study, the components and oleuropein content in 10 types of products were analyzed using a developed method with ultra-performance liquid chromatography to quadrupole time-of-flight mass spectrometry, charge of aerosol detector, and photodiode array. The total of 18 compounds including iridoids (1, 3, 4, 14, and 16-18), coumarin (2), phenylethanoids (5, 9, and 11), flavonoids (6-8, 10, 12, and 13), lignan (15), were tentatively identified in the leaves extract based high resolution mass spectrometry data, and the content of oleuropein in each product was almost identical between two detection methods. The oleuropein in three commercial product (A, G, H) was contained more over the suggested content, and it of five products (B, E, H, I, J) were analyzed within 5-10% error range. However, the two products (C, D) were found far lower than suggested contents. This study provides that analytical results of oleuropein could be a potential information for the quality control of leaf extract for a manufactured functional food.

• Journal of Science and Technology Studies
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• v.4 no.2 s.8
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• pp.103-127
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• 2004

This paper analyzes the strategic planning process of NASA (National Aeronautics and Space Administration) including its center, GSFC (Goddard Space Flight Center) in the framework of strategic planning in publicly funded R&D organizations. To construct this framework, theories have been considered mainly focused on strategic management and planning, its application on public sector, and characteristics of R&D activities. As a result, the framework could be set up in accordance with the process of strategic planning. Also, as a case study, we explored the practice of strategic planning process and organizational implementation of NASA and GSFC. During the analysis on the strategic process of NASA and GSFC, we could draw some lessons out as follows: First, we should consider the differences between private and public sectors when we establish strategic planning in public sector. Second, the stakeholder analysis should be involved in setting the mission, goals, and strategies of an organization. Third, it is necessary to identify and assess the socio-economic effects or public benefits by R&D programs of the organization and use the feedback on its goal. Fourth, to implement strategic planning effectively, planning process should be closely integrated with the management process such as setting goals, securing budgets, and evaluating the organization. Conclusively, the analysis on NASA and GSFC contribute to implementing strategic planning in publicly funded R&D organizations by providing the appropriately modified framework. As an extension of this study, more deliberate analysis on various practices of strategic planning and performance indicators should be followed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.7
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• pp.445-454
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• 2022

Ice accretion on the aircraft components, such as wings, fuselage, and empennage, can occur when the aircraft encounters a cloud zone with high humidity and low temperature. The prevention of ice accretion is important because it causes a decrease in the aerodynamic performance and flight stability, thus leading to fatal safety problems. In this study, a shape design optimization of a multi-element airfoil is performed to minimize the amount of ice accretion on the high-lift device including leading-edge slat, main element, and trailing-edge flap. The design optimization framework proposed in this paper consists of four major parts: air flow, droplet impingement and ice accretion simulations and gradient-free optimization algorithm. Reynolds-averaged Navier-Stokes (RANS) simulation is used to predict the aerodynamic performance and flow field around the multi-element airfoil at the angle of attack 8°. Droplet impingement and ice accretion simulations are conducted using the multi-physics computational analysis tool. The objective function is to minimize the total mass of ice accretion and the design variables are the deflection angle, gap, and overhang of the flap and slat. Kriging surrogate model is used to construct the response surface, providing rapid approximations of time-consuming function evaluation, and genetic algorithm is employed to find the optimal solution. As a result of optimization, the total mass of ice accretion on the optimized multielement airfoil is reduced by about 8% compared to the baseline configuration.

• Nutrition Research and Practice
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• v.14 no.2
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• pp.102-108
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• 2020

BACKGROUND/OBJECTIVES: In Oriental medicine, certain foods may be beneficial or detrimental based on an individual's constitution; however, the scientific basis for this theory is insufficient. The purpose of this study was to investigate the effect of body constitution, based on the Sasang type of Korean traditional medical classification system, on the bioavailability of soy isoflavones of Cheonggukjang, a quick-fermented soybean paste. SUBJECTS/METHODS: A pilot study was conducted on 48 healthy Korean men to evaluate the bioavailability of isoflavone after ingestion of food based on constitution types classified by the Sasang typology. The participants were classified into the Taeeumin (TE; n = 15), Soyangin (SY; n = 15), and Soeumin (SE; n = 18) groups. Each participant ingested 50 g of Cheonggukjang per 60 kg body weight. Thereafter, blood was collected, and the soy isoflavone metabolites were analyzed by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. Ntrikinetic analysis of individual isoflavone-derived metabolites was performed. RESULTS: Our nutrikinetic analysis identified 21 metabolites derived from isoflavones in the blood samples from 48 healthy Korean men (age range, 21-29 years). Significant differences were observed in the time to maximum concentration (T_max) and elimination half-life (t_1/2) for nine metabolites among the three groups. The T_max and t_1/2 of the nine metabolites were higher in the SE group than in the other groups. Moreover, the absorption rates, as determined by the area under the plasma-level curve (AUC) values of intact isoflavone, were 5.3 and 9.4 times higher in the TE group than in the SY and SE groups, respectively. Additionally, the highest AUC values for phase I and II metabolites were observed in the TE group. CONCLUSIONS: These findings indicate that isoflavone bioavailability, following Cheonggukjang insgestion, is high in individuals with the TE constitution, and relatively lower in those with the SE and SY constitutions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.394-403
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• 2019

This research focuses on the perception of security screeners using a full body scanner at airport which had been newly introduced to terminal 2 of Incheon Int'l airport. To accomplish the purpose of research, this paper used UTAUT (Unified Theory of Acceptance and Use of Technology) model. Through an empirical analysis, it was proven the factors consisting of technological acceptance and how those factors affect both organizational innovation at airport and job satisfaction of security screeners. According to an empirical analysis, it was found out all the factors of technological acceptance have a significant effect on both organizational innovation and job satisfaction. However, only the effort expectation was shown to have a significant negative effect on the two dependant variables contrary to the other variables (performance expectation, behavioral intention and self efficacy. It was also proven organizational innovation had a moderating effect between technological acceptance and job satisfaction. Such results suggested organizational innovation at airport security division is necessary to enhance job satisfaction using a newly introduced full body scanner.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.2
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• pp.281-290
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• 2022

In Korea, the number of national facilities for which a safety inspection is mandatory is increasing, and a safer safety inspection method is needed. This study aimed to increase the efficiency of the bridge safety inspection by enabling rapid exterior inspection while securing the safety of inspectors by using drones to perform the safety inspections of bridges, which had mainly relied on visual inspections. For the research, the Youngjong Grand Bridge in Incheon was selected as a test bed and was divided into four parts: the warren truss, suspension bridge main cable, main tower, and pier. It was possible to establish a five-step standard procedure for drone safety inspections. The step-by-step contents of the standard procedure obtained as a result of this research are: Step 1, facility information collection and analysis, Step 2, analysis of vulnerable parts and drone flight planning, Step 3, drone photography and data processing, Step 4, condition evaluation by external inspection, Step 5, building of external inspection diagram and database. Therefore, if the safety inspections of civil engineering facilities including bridges are performed according to this standard procedure, it is expected that these inspection can be carried out more systematically and efficiently.