• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.393-401
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• 2007

This study was performed to investigate the antioxidant activity of Korean ginseng using an ORAC(Oxygen Radical Absorbance Capacity) assay. Four fractions each (80% ethanol, ethyl acetate, water saturated 1-butanol, and water) were obtained from different ginseng samples (White Ginseng: ; 6 yrs-., 5 yrs-., ; Cork Ginseng: ; 5 yrs-., 4 yrs-.). The saponin content of each fraction was quantified by LC/MS, and the antioxidant capacity of the ginseng was measured by the ORAC assay. The ORAC method, which was recently validated using automatic liquid handling systems, has been adapted for manual handling with the use of a conventional fluorescence microplate reader. Furthermore, the ORAC assay provides a direct measure of hydrophilic chain-breaking antioxidant capacity against peroxy radical, which is the exiting and emission of 2,2'-Azobis (2-methylpropionamidine)-dihychloride (AAPH). As a result of our experiments, ginsenosides Rg1 and Rb1 were the two major saponins found in the ginseng samples, and Rc, Rb2, Re, Rd, Rg3, and Rh1 were detected in a small quantities. For the antioxidant capacities of the fractions (80% ethanol, ethyl acetate, butanol, and water), we found that the organic solvent fraction had similar antioxidant capacities, and were higher than the capacity of the water fraction. When determining the similarities in each fraction, only the ethyl acetate fraction showed similarity compared to other fractions (p>0.05). The antioxidant capacity of ginseng may come from phenolic compounds and some nonpolar saponins. However, based on the results of this study, we hypothesize that some acidic polysaccharides and other biological components may contribute to its antioxidant capacity. Additional research is required to determine other possible biological response modifiers that contribute to the antioxidant capacity of ginseng.

• Archives of design research
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• v.17 no.1
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• pp.153-162
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• 2004

This paper focused on the effect of Kansei design on the web in branding as well as its influence factors. As a key of this research, it classified web users' Kansei into five categories; 1) functional Kansei, 2) sensoryKansei, 3) psychological Kansei, 4) relational Kansei and 5) cultural Kansei, and organized relevant factors. Online surveys were conducted on seven websites of the fast food brands in Korea (Lotteria, Mcdonald, BurgerKing, Popeyes, KFC, Pizza Hut, Domino's) which are targeting 463 male and females in 20s. As a result, an average of 58% responded that they had a positive Kansei experience and could enhanceits brand preference. Of the sensory Kansei, visual design factors were the one that gave the greatest effect on brand preference enhancement. Regarding the functional Kansei satisfaction, such as user convenience and access speed were also one of the most crucial variables for the whole Kansei satisfaction. Moreover, the preference enhancement brought not only a positive effect on its reliability but also its brand image and consumers' purchasing desire. Based on the survey results, the additional FGI (Focus Group Interview) had been conducted and determined \circled1 what kind of major Kansei that users wanted to have satisfied, \circled2 what type of design can give strong Kansei appeal to its users, and \circled3what design factors gave an effect on sensory emotion. In the course of this research, Itried to renew the awareness of the web importance as a major channel in non-mass interactive marketing, and suggest the effect and its possibility of emotional branding through Kansei design in the web as well as design principles of strategic Kansei design.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.208-215
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• 2020

This study investigated the relationship among gait variables and physical fitness variables for Korean elderly people. Two hundred elderly people aged 65 to 85, (100 men and 100 women) participated in this study. They performed senior fitness test consisting of 6 tests, 3 additional physical tests (vertical jump, one leg stand, and grip force), body composition measures, and gait test. The gait test used shoes having an inertia measurement device in the outer-soles. The results indicated that the stride length, 6-min walking, lean body mass, and dumbbell curls were significantly affected by age (the above 75 group vs. the below 75 group). Among 33 measured parameters, the principal component analysis (PCA) revealed five PCs such as gait characteristics, physical features, gait variability, and fitness levels. In addition, the correlation analysis showed that the preferred walking speed was significantly, positively associated with stride length and single support time, whereas it was negatively associated with double support time and gait variability.(Ed note: please confirm my modification) In conclusion, sarcopenia should be avoided in elderly people, and resistance exercise is highly recommended to help elderly people maintain their gait ability.

• Tunnel and Underground Space
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• v.22 no.4
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• pp.227-242
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• 2012

Youngju multipurpose dam is planned to minimizing the damage by flood and obtaining the water for industrial use in Nakdong river region. Faults in rock mass have strong influences on the behaviors of dam structure. Thus, it is very important to analyse for the characteristics of fault rocks in dam design. However, due to the limitation of geotechnical investigation in design stages, engineers have to carry out the additional geological survey including directional boring to find the distribution of faults and the engineering properties of faults for stability of dam. Especially, the selection of location of dam and type of dam considering fault zone must be analyzed through various experimental and numerical analysis. In this study, various geological survey and field tests were carried out to analyse the characteristics of the large fault zone through the complex dam is designed in foundation region. Also, the distribution of structural geology, the shape of faults and the mechanical properties of fault rock were studied for the reasonable design of the location and type of dam for long-term stability of the complex dam.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.1
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• pp.32-48
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• 2018

The mechanisms of $CH_4$ uptake into and release from the ocean are not well understood due mainly to complexity of the biogeochemical cycle and to lack of regional-scale and/or process-scale observations in the marine boundary layers. Without complete understanding of oceanic mechanisms to control the carbon balance and cycles on a various spatial and temporal scales, however, it is difficult to predict future perturbation of oceanic carbon levels and its influence on the global and regional climates. High frequency, high precision continuous measurements for carbon isotopic compositions from dissolved $CH_4$ in the surface ocean and marine atmosphere can provide additional information about the flux pathways and production/consumption processes occurring in the boundary of two large reservoirs. This paper introduces recent advances on optical instruments for real time $CH_4$ isotope analysis to diagnose potential applications for in situ, continuous measurements of carbon isotopic composition of dissolved $CH_4$. Commercially available, three laser absorption spectrometers - quantum cascade laser spectroscopy (QCLAS), off-axis integrated cavity output spectrometer (OA-ICOS), and cavity ring-down spectrometer (CRDS) are discussed in comparison with the conventional isotope ratio mass spectrometry (IRMS). Details of functioning and performance of a CRDS isotope instrument for atmospheric ${\delta}^{13}C-CH_4$ are also given, showing its capability to detect localized methane emission sources.

• Archives of Reconstructive Microsurgery
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• v.19 no.2
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• pp.97-100
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• 2010

Purpose: Epidermolysis bullosa is a rare genetic disease, characterized by the presence of extremely fragile skin and formation of recurrent blister resulting from even a minor mechanical injury. Squamous cell carcinoma (SCC) is recognized as a complication of the chronic scarring associated with dystrophic epidermolysis bullosa (DEB). When a soft tissue defect happens in a patient with epidermolysis bullosa, it is difficult to cover it with a skin graft or a flap. We describe the successful use of a pedicled deep inferior epigastric perforator flap for the reconstruction of SCC associated with DEB in the groin. Methods: A 29-year-old man diagnosed with DEB at birth sustained an ulcer increasing in the right groin for the last 7 months. Under general anesthesia, the mass lesion and lymph nodes were removed and the resulting defect was covered with a pedicled deep inferior epigastric perforator flap. Results: The flap survived completely and his postoperative course was uneventful. Histopathological examination revealed a SCC in the right groin and malignant tumor cells in the removed lymph nodes as well. Additional positron emission tomogram showed a malignant lesion in the ileocecal area with regional lymph node metastasis. The patient was referred to an oncologist for chemotheraphy, but the patient refused to take it. During a 4-month follow-up period, there was no recurrence in the right groin. Conclusion: We suggest that perforator flaps can be considered as a reliable alternative for the reconstruction of soft tissue defects in a patient with DEB.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.993-999
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• 2008

A girder height limitation is the critical parameter for rapid construction of bridge deck and construction space limitation especially in urban area such as high population area and high density habitats. A standard post-tensioned I-shaped concrete girder usually demands relatively higher girder height in order to retain sufficient moment arm between compression force and tensile force. To elaborate this issue, a small U-shaped section with wide flanges can be used as a possible replacement of I-shaped standard girder. This prestressed concrete box girder allows more flexible girder height adjustment rather than standard I-shaped post-tensioned girder plus additional torsion resistance benefits of closed section. A 30m-long, 1.7m-high and 3.63m-wide actual small prestressed concrete box girder is designed and a laboratory test for its static behaviors by applying 6,200kN amount of load in the form of 4-point bending test was performed. The load-deflection curve and crack patterns at different loading stage are recorded. In addition, to extracting the dynamic characteristics such as natural frequency and damping ratio of this girder, several excitation tests with artificial mechanical exciter with un-symmetric mass are carried out using operational frequency sweep-up. Nonlinear finite element analysis of this 4 point bending test under monotonic static load is investigated and discussed with aids of concrete damaged plasticity formulation using ABAQUS program.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.613-620
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• 2021

A flow channel shape of PEMFC has an influence on the internal flow uniformity. If the reactant distribution in a flow path is not uniform during operation, both catalyst deactivation and mechanical damage of membrane could occur resulting in decreasing the membrane electrode assembly (MEA) durability. Numerous studies concerning flow design have been conducted to make smooth supply and uniform distribution of reactants in fuel cells. The baffle of flow path could improve fuel cell performance through the forced convection effect. A sub-channel, as an additional air flow path, could increase the reactant concentration and reduce the mass transfer loss via a smooth water discharge. In this study, computational fluid dynamics (CFD) was used to analyze the effect of blocks and sub-channels on the current density and oxygen concentration of the fuel cell. As a result, the limit current density and oxygen concentration at a rear block increased when using blocks and sub-channels in a flow channel. In particular, the current density increased significantly when the sub-channel was placed between two blocks. Also, the sub-channel position was optimized by analyzing the oxygen concentration, and the oxygen concentration was recovered at a rear block in the fuel cell.

• Journal of Navigation and Port Research
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• v.45 no.6
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• pp.366-371
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• 2021

This study suggests surface wave communication, which uses a metal surface as a medium, to provide wireless communication in the extreme environment due to surrounding metal materials on vessels. The test was conducted on a G/T 265 tons tug boat to confirm the possibility of surface wave communication between a bridge and each designated space in the ship. As a result, the transmission speed was 13Mbps on average. In a test case of the bridge via the engine room, the transmission speed was 4.3Mbps on engine running and 1.2Mbps on sailing. It overcame this by partially changing the equipment installation location. Surface wave communication in bow storage, a fully enclosed space, had 8Mbps better transmission speed than wireless communication; this confirmed the superiority of surface wave communication in confined spaces on a vessel. Additional surface wave generators were designed and applied to resolve the paint issue. It is expected to use surface wave communication to implement the new wireless solution for Maritime-IoT system on vessels.

• Journal of Life Science
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• v.29 no.1
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• pp.84-89
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• 2019

Previous screening of novel antibacterial agents revealed that some bacterial isolates exhibited antibiotic activity against both gram-positive and gram-negative bacteria and that they showed antibacterial activity, even against methicillin-resistant Staphylococcus aureus (MRSA). Among these isolates, one bacterial strain, BCNU 1204, was identified as Pseudomonas aeruginosa using phenetic and phylogenetic analysis, based on 16S ribosomal RNA gene sequences. The maximum productivities of antimicrobial substances of BCNU 1204 were obtained after being cultured at $35^{\circ}C$ and pH 7.0 for 4 d in King's medium B (KMB). Dichloromethane (DCM) and ethylacetate (EA) extracts of P. aeruginosa BCNU 1204 exhibited strong antimicrobial activity, particularly against gram-positive bacteria. The EA extracts exhibited broad-spectrum activity against antibiotic resistant strains. Fraction 5-2, was obtained by recycling preparative liquid chromatography (LC) and preparative thin-layer chromatography (TLC) and was identified as phenazine-1-carboxylic acid belonging to phenazines using gas chromatography and mass spectrometry (GC/MS). Its minimum inhibitory concentration (MIC) values were $25{\mu}g/ml$, $50{\mu}g/ml$, ${\geq}25{\mu}g/ml$, and ${\geq}50{\mu}g/ml$ for MRSA CCARM 3089, 3090, 3091, and 3095 strains, respectively. P. aeruginosa BCNU 1204 may be a potential resource for the development of anti-MRSA antibiotics. Additional research is required to identify the active substance from P. aeruginosa BCNU 1204.