• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.5
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• pp.7-13
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• 2006

This study was to evaluate the effect of carbon content on metallic change and fatigue characteristics with Fe-29%Ni-17%Co, low heat expansion alloy, widely using electronic components, precision machines, and sealing with glass and metal etc. The steels were fabricated with variation of carbon content, 0, 0.03, 0.06, 0.1, and 0.20% with VIM and tensile test and fatigue test were performed to achieve the above purpose. The more carbon content, the higher hardness value and yield strength. But elongation of 0.03%C, 0.06%C, and 0.10%C specimen decreased about 2.2%, 1.5% and 0.8% respectively more than that of the base metal. Especially the strength and elongation of 0.20%C specimen increased simultaneously about 14.4% and 7.5%. Fatigue life of 0.03%C specimen decreased but the more carbon content, the higher fatigue life over 0.06% carbon content more than that of base metal.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.6
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• pp.1040-1050
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• 1995

The Purposes of this study were to investigate the choice dimensions in purchasing the medium-low priced casual clothing, the influence of them on the preference of medium-low priced casual clothing, and the brand images of six medium-low priced casual clothing using the perceptual map. The Questionnaires were administered to 540 college students living in Seoul (340) and County of Chungnam(200). The data were analyzed by frequency, factor analysis and multiple regression analysis. The results were summarized as follows: 1) The choice dimensions in purchasing the medium-low price casual clothing were identified as exclusiveness/style, intrinsic characteristics, promotion and price/distance. 2) Exclusiveness/style dimension influenced most on the preference of medium-low priced casual, intrinsic characteristics, price/distance dimension were followed. Promotion dimension appeared to have an insignificant influence. These results were consistent in both Seoul and the County of Chungnam. 3) Perceptual mapping showed Hunt and J-vim had the best brand images, Maypole and Omphalos were followed. Tipi Cosi and I-land appeared to have the worst brand image. The college students living in the County of Chungnam perceived that all six brands of medium low priced casual clothing to be exclusive in their style. In addition, it was perceived less promoted, more expensive and farther than Seoul counterparts.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.83-91
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• 1997

The vein-necrosis strain or potato virus Y (PVY-Vff) and black shank (Phytophlhora parasitica roar. nicotianae) causes severe damage on burley tobacco(Wicotiana tabacum L.) in Korea, A new burley tobacco resistance to PVY and black shank, KB 110, was developed by Korea Ginseng and Tobacco Research Institute. It was developed from the cross of Burley 21 with TC 591 in 1990, and was backrossed to Burley 21 in the following season. TC 591 has resistance to PVY and moderate resistance to race 0 of black shank, but it is susceptible to tobacco mosaic vim (TMV). KB 110 was evaluated for its resistance to PVY, TMV and black shank in the greenhouse and at fields for preliminary and performance trials. KB 110 which has secreting glandular trichomes was resistant to PVY-VN, TW and black shank. It had an erect growth habit and two more leaves per plant than that of Burley 21, and matures two to three days later. It yielded approximately 3 percent more cured leaf than the standard cultivar Burley 21, but other plant characteristics were very similar to those of Burley 21. It had acceptable standards for chemical and physical characteristics of lured leaf on regional farm test in 1995-1997. KB 110 produced average yields of good quality tobaccos and was appeared to be resistant to PVY inwhere occurrence of the virus are severe chronic at burley growing area.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.4 no.1
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• pp.23-42
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• 1991

This study were done to know the effects of Dangkiyeumja on the in vivo and in vitro immune responses of mice. The recipes of Dangkiyeumja used in this study enhanced such, cellular functions of immunocytes as phagocytic capacity of macrophages, rossett-eforming abilities of splenocytes and metabolic activities of lymphocytes, However, the same recipes decreased the formation of such reactive oxygen intermediates(ROI) as superoxide and hydrogenperoxide from the macrophages. The effects of the same recipes on the in vim immune responses was suppressive on the cellular immune response(CIR)measured by delayed-type hypersensitivity against dinitrofluorobenzene and mildly enhancing for the humoral immune response measured by antibody production against sheep red blood cells. The results of this study could be summarized as follow: 1. Administration of Dangkiyeumja enhanced the phagocytic activity of the murine macrophage. 2. Administration of Dangkiyeumja decreased the formation of ROI in the murine macrophage 3. Administration of Dangkiyeumja increased the number of the splenic rotte forming cells in the mouse. 4. Administration of DangKiyeumja did not effect the antibody production against sheep red blood cells. 5. Administration of Dangkiyeumja depressed the delayed-type hypersenitivity against dinitrofluoro benzene in the mouse. The result of this study suggest that Dangkiyeumja could ameliorate the hypersensitivity reactions by reducing the formation of ROI and decreasing the CIR without affecting the other functions of immunocytes.

• Korean Journal of Materials Research
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• v.7 no.3
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• pp.234-243
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• 1997

The crystal structure of arc melted $ZrV_{x}Mn_{1-x}Ni_{1.0},\;ZrV_{x}Mn_{0.8-x}Ni_{1.2},\;ZrV_{x}Mn_{0.6-x}Ni_{1.4}$ alloys which are known to have AB2 type Laves structure was investigated. They had mixed phases of C14 and C15. The radius ratio ($r_{A}/r_{B}$) of atoms in A site to that of B site was found to be an important parameter in explaining the omposition dependence of the crystal structure The C15 structure showed a linear increase with the ratio in as-cast conditions. However, the annealed alloys revealed a definite ratio at which the stability of both phases are divided distinctly. The composition of the alloys could be closely controlled by maintaining the argon pressure in the chamber over 1 arm during arc melting. In contrast, the alloy ingot melted in VIM showed a significant loss of hln.

• Korean Journal of Clinical Laboratory Science
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• v.42 no.2
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• pp.71-80
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• 2010

Pseudomonas aeruginosa are important nosocomial pathogens. Their resistance to carbapenem is increasing and causing concerns in Korea. An increasing prevalence of carbapenem resistance mediated by acquired carbapenemase is being reported. Over a 10 month-period from July 2007 to April 2008, 32 strains of imipenem-nonsusceptible P. auruginosa were isolated from Kangwon National University Hospital. To determine the prevalence and genotypes of the carbapenemase-producing clinical isolates, the antibiotic susceptibility was determined by Microscan Walkaway 96 SI System and the carbapenem activity was detected by the modified Hodge test and the imipenem-EDTA-SMA double-disk synergy test. The metallo-${\beta}$-lactamase gene and OXA-type ${\beta}$-lactamase gene reported in Korea were detected by PCR. As for the result of PCR, 30 isolates of P. aeruginosa were found to have $bla_{IMP-1}$-like and 1 isolate was found to have $bla_{IMP-1}$-like and $bla_{IMP-2}$. No clinical isolates were found to have $bla_{SIM-1}$, $bla_{OXA-23}$-like and $bla_{OXA-24}$-like. Random amplified polymorphic DNA (RAPD)-PCR and dendrogram for genetical similarity to band patterns of each clinical isolates were examined. P. aeruginosa were grouped into 7 clusters of up to 50% of similarity index. In the P. aeruginosa group, PS3 was resistant to the most antibiotics, PS1 was susceptible to the most antibiotics. PS7 was resistant to aztreonam unlike other groups. This is the first report of prevalence of carbapenemase in Chuncheon.

• Ocean Systems Engineering
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• v.14 no.2
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• pp.171-210
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• 2024

This paper focuses on the rigorous and holistic fatigue analysis of mooring chains for a deep draft semi-submersible platform in the challenging environment of the central Gulf of Mexico (GoM). Known for severe hurricanes and strong loop/eddy currents, this region significantly impacts offshore structures and their mooring systems, necessitating robust designs capable of withstanding extreme wind, wave and current conditions. Wave scatter and current bin diagrams are utilized to assess the probabilistic distribution of waves and currents, crucial for calculating mooring chain fatigue. The study evaluates the effects of Vortex Induced Motion (VIM), Out-of-Plane-Bending (OPB), and In-Plane-Bending (IPB) on mooring fatigue, alongside extreme single events such as 100-year hurricanes and loop/eddy currents including ramp-up and ramp-down phases, to ensure resilient mooring design. A detailed case study of a deep draft semi-submersible platform with 16 semi-taut moorings in 2,500 meters of water depth in the central GoM provides insights into the relative contributions of wave scatter diagram, VIMs from current bin diagram, the combined stresses of OPB/IPB/TT and extreme single events. By comparing these factors, the study aims to enhance understanding and optimize mooring system design for safety, reliability, and cost-effectiveness in offshore operations within the central GoM. The paper addresses a research gap by proposing a holistic approach that integrates findings from various contributions to advance current practices in mooring design. It presents a comprehensive framework for fatigue analysis and design optimization of mooring systems in the central GoM, emphasizing the critical importance of considering environmental conditions, OPB/IPB moments, and extreme single events to ensure the safety and reliability of mooring systems for offshore platforms.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.240-245
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• 2012

Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium that causes serious infection, particularly in immunocompromised patients. Also, P. aeruginosa possessing carbapenem-resistant metallo-${\beta}$-lactamases (MBL) has been reported with increasing frequency in Korea. We therefore analyzed the level of multidrug-resistant clinical P. aeruginosa isolated from a secondary hospital in Korea in 2010. A total of 92 isolates of P. aeruginosa were collected from Sahmyook Medical Center in 2010. Susceptibility to antimicrobial agents was determined by analysis of the minimum inhibitory concentration test; the inhibitor-potentiated disk diffusion (IPD) test was performed for MBL detection. RAPD-PCR was used for genotyping to rapidly characterize P. aeruginosa strains isolated from clinical patients. The percentages of non-susceptible isolates were as follows: 40.2% to ceftazidime, 58.7% to meropenem, 56.5% to gentamicin, 46.7% to tobramycin, 62.0% to ciprofloxacin and 97.8% to chloramphenicol. The 29 multidrug-resistant strains were screened by the IPD test: of the 21 PCR-positive isolates, 19 were IPM-1 producers and 2 were VIM-2 producers. Among the 19 IMP-1-producing P. aeruginosa isolates, 16 isolates showed similar patterns, and three different banding patterns were observed. The proportion of IMP-1-producing multidrug-resistant P. aeruginosa from clinical isolates steadily increased in this secondary hospital in Korea in 2010. This study provides information about the antimicrobial-resistant patterns and genotype of multidrug-resistant P. aeruginosa isolated from clinical isolates in Korea, 2010.

• Development and Reproduction
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• v.15 no.4
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• pp.339-347
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• 2011

Human eyelid adipose-derived stem cells (hEAs) and amniotic mesenchymal stem cells (hAMs) are very valuable sources for the cell therapeutics. Both types of cells have a great proliferating ability in vitro and a multipotency to differentiate into adipocytes, osteoblasts and chondrocytes. In the present study, we evaluated their stem cell characteristics after long-time cryopreservation for 6, 12 and 24 months. When frozen-thawed cells were cultivated in vitro, their cumulative cell number and doubling time were similar to freshly prepared cells. Also they expressed stem cell-related genes of SCF, NANOG, OCT4, and TERT, ectoderm-related genes of NCAM and FGF5, mesoderm/endoderm-related genes of CK18 and VIM, and immune-related genes of HLA-ABC and ${\beta}$2M. Following differentiation culture in appropriate culture media for 2-3 weeks, both types of cells exhibited well differentiation into adipocyte, osteoblast, and chondrocyte, as revealed by adipogenic, osteogenic or chondrogenic-specific staining and related genes, respectively. In conclusion, even after long-term storage hEAs and hAMs could maintain their stem cell characteristics, suggesting that they might be suitable for clinical application based on stem cell therapy.

• Journal of Microbiology
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• v.45 no.4
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• pp.358-363
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• 2007

Multi-drug resistant Pseudomonas aeruginosa has been implicated in a variety of serious therapeutic problems in clinical environments. Among the 968 P. aeruginosa isolates obtained from two hospitals in Daegu, Korea, we acquired 17 isolates that were resistant to all available tested antimicrobial agents, with the exception of colistin (colistin-only sensitive). We characterized the antimicrobial susceptibilities, $metallo-{\beta}-lactamases$, and epidemiological relatedness among the colistin-only sensitive P. aeruginosa isolates. All colistin-only sensitive isolates were positive in the modified Hodge test and imipenem-EDTA synergy test, thereby indicating the production of $metallo-{\beta}-lactamases$. 11 isolates from the secondary hospital and six isolates from the tertiary teaching hospital harbored $bla_{VIM-2}$ and $bla_{IMP-1}$, respectively. The pulsed-field gel electrophoretic analysis of the SpeI-digested DNA from P. aeruginosa isolates indicated that two different clones of colistin-only sensitive P. aeruginosa originated from each hospital, and had spread within the hospital environment. Overall, colistin-only sensitive P. aeruginosa was detected in Korea for the first time, but no pan-drug resistant bacteria were identified. Nationwide surveillance is required in order to monitor the emergence of colistin-only sensitive or pan-drug resistant bacteria.